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Int. J. Mol. Sci., Volume 15, Issue 9 (September 2014) – 130 articles , Pages 14909-17203

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932 KiB  
Article
A Combined Experimental and Computational Study of Vam3, a Derivative of Resveratrol, and Syk Interaction
by Ming Jiang, Renping Liu, Ying Chen, Qisheng Zheng, Saijun Fan and Peixun Liu
Int. J. Mol. Sci. 2014, 15(9), 17188-17203; https://doi.org/10.3390/ijms150917188 - 25 Sep 2014
Cited by 9 | Viewed by 6914
Abstract
Spleen tyrosine kinase (Syk) plays an indispensable role through preliminary extracellular antigen-induced crosslinking of Fc receptor (FcR) in the pathogenesis of autoimmune disorders, such as rheumatoid arthritis. In this study, we identify Vam3, a dimeric derivative of resveratrol isolated from grapes, as an [...] Read more.
Spleen tyrosine kinase (Syk) plays an indispensable role through preliminary extracellular antigen-induced crosslinking of Fc receptor (FcR) in the pathogenesis of autoimmune disorders, such as rheumatoid arthritis. In this study, we identify Vam3, a dimeric derivative of resveratrol isolated from grapes, as an ATP-competitive inhibitor of Syk with an IC50 of 62.95 nM in an in vitro kinase assay. Moreover, docking and molecular dynamics simulation approaches were performed to get more detailed information about the binding mode of Vam3 and Syk. The results show that 11b-OH on ring-C and 4b-OH on ring-D could form two hydrogen bonds with Glu449 and Phe382 of Syk, respectively. In addition, arene-cation interaction between ring-D of Vam3 and Lys402 of Syk was also observed. These results indicate that ring-C and D play an essential role in Vam3–Syk interaction. Our studies may be helpful in the structural optimization of Vam3, and also aid the design of novel Syk inhibitors in the future. Full article
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1072 KiB  
Review
Chromatin Structure and Dynamics in Hot Environments: Architectural Proteins and DNA Topoisomerases of Thermophilic Archaea
by Valeria Visone, Antonella Vettone, Mario Serpe, Anna Valenti, Giuseppe Perugino, Mosè Rossi and Maria Ciaramella
Int. J. Mol. Sci. 2014, 15(9), 17162-17187; https://doi.org/10.3390/ijms150917162 - 25 Sep 2014
Cited by 14 | Viewed by 8111
Abstract
In all organisms of the three living domains (Bacteria, Archaea, Eucarya) chromosome-associated proteins play a key role in genome functional organization. They not only compact and shape the genome structure, but also regulate its dynamics, which is essential to allow complex genome functions. [...] Read more.
In all organisms of the three living domains (Bacteria, Archaea, Eucarya) chromosome-associated proteins play a key role in genome functional organization. They not only compact and shape the genome structure, but also regulate its dynamics, which is essential to allow complex genome functions. Elucidation of chromatin composition and regulation is a critical issue in biology, because of the intimate connection of chromatin with all the essential information processes (transcription, replication, recombination, and repair). Chromatin proteins include architectural proteins and DNA topoisomerases, which regulate genome structure and remodelling at two hierarchical levels. This review is focussed on architectural proteins and topoisomerases from hyperthermophilic Archaea. In these organisms, which live at high environmental temperature (>80 °C <113 °C), chromatin proteins and modulation of the DNA secondary structure are concerned with the problem of DNA stabilization against heat denaturation while maintaining its metabolic activity. Full article
(This article belongs to the Special Issue Identification and Roles of the Structure of DNA)
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1146 KiB  
Review
Defining Molecular Sensors to Assess Long-Term Effects of Pesticides on Carcinogenesis
by Fanny L'Héritier, Maud Marques, Myriam Fauteux and Luc Gaudreau
Int. J. Mol. Sci. 2014, 15(9), 17148-17161; https://doi.org/10.3390/ijms150917148 - 25 Sep 2014
Cited by 13 | Viewed by 7083
Abstract
The abundance of dioxins and dioxin-like pollutants has massively increased in the environment due to human activity. These chemicals are particularly persistent and accumulate in the food chain, which raises major concerns regarding long-term exposure to human health. Most dioxin-like pollutants activate the [...] Read more.
The abundance of dioxins and dioxin-like pollutants has massively increased in the environment due to human activity. These chemicals are particularly persistent and accumulate in the food chain, which raises major concerns regarding long-term exposure to human health. Most dioxin-like pollutants activate the aryl hydrocarbon receptor (AhR) transcription factor, which regulates xenobiotic metabolism enzymes that belong to the cytochrome P450 1A family (that includes CYP1A1 and CYP1B1). Importantly, a crosstalk exists between estrogen receptor α (ERα) and AhR. More specifically, ERα represses the expression of the CYP1A1 gene, which encodes an enzyme that converts 17β-estradiol into 2-hydroxyestradiol. However, (ERα) does not repress the CYP1B1 gene, which encodes an enzyme that converts 17β-estradiol into 4-hydroxyestradiol, one of the most genotoxic estrogen metabolites. In this review, we discuss how chronic exposure to xenobiotic chemicals, such as pesticides, might affect the expression of genes regulated by the AhR–ERα crosstalk. Here, we focus on recent advances in the understanding of molecular mechanisms that mediate this crosstalk repression, and particularly on how ERα represses the AhR target gene CYP1A1, and could subsequently promote breast cancer. Finally, we propose that genes implicated in this crosstalk could constitute important biomarkers to assess long-term effects of pesticides on human health. Full article
(This article belongs to the Special Issue Mechanisms of Toxicity of Dioxins and Related Compounds)
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Article
High-Dose Diosgenin Reduces Bone Loss in Ovariectomized Rats via Attenuation of the RANKL/OPG Ratio
by Zhiguo Zhang, Changheng Song, Xiaowei Fu, Meijie Liu, Yan Li, Jinghua Pan, Hong Liu, Shaojun Wang, Lihua Xiang, Gary Guishan Xiao and Dahong Ju
Int. J. Mol. Sci. 2014, 15(9), 17130-17147; https://doi.org/10.3390/ijms150917130 - 25 Sep 2014
Cited by 42 | Viewed by 7095
Abstract
The aim of this study was to evaluate effect of diosgenin (DG) on rats that had osteoporosis-like features induced by ovariectomy (OVX). Seventy-two six-month-old female Wistar rats were subjected to either ovariectomy (n = 60) or Sham operation (SHAM group, n = [...] Read more.
The aim of this study was to evaluate effect of diosgenin (DG) on rats that had osteoporosis-like features induced by ovariectomy (OVX). Seventy-two six-month-old female Wistar rats were subjected to either ovariectomy (n = 60) or Sham operation (SHAM group, n = 12). Beginning at one week post-ovariectomy, the OVX rats were treated with vehicle (OVX group, n = 12), estradiol valerate (EV group, n = 12), or DG at three doses (DG-L, -M, -H group, n = 12, respectively). After a 12-week treatment, administration of EV or DG-H inhibited OVX-induced weight gain, and administration of EV or DG-H or DG-M had a significantly uterotrophic effect. Bone mineral density (BMD) and indices of bone histomorphometry of tibia were measured. Levels of protein and mRNA expression of osteoprotegerin (OPG) and receptor activator of nuclear factor kappa-B ligand (RANKL) in tibia were evaluated by immunohistochemistry and in situ hybridization. Our results show that DG at a high dose (DG-H) had a significant anti-osteoporotic effect compared to OVX control. DG-H treatment down-regulated expression of RANKL and up-regulated expression of OPG significantly in tibia from OVX rats compared to control, and thus lowered the RANKL/OPG ratio. This suggests that the anti-osteoporotic effect of DG might be associated with modulating the RANKL/OPG ratio and DG had potential to be developed as alternative therapeutic agents of osteoporosis induced by postmenopause. Full article
(This article belongs to the Section Biochemistry)
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Article
Methylphenidate Ameliorates Depressive Comorbidity in ADHD Children without any Modification on Differences in Serum Melatonin Concentration between ADHD Subtypes
by Isabel Cubero-Millán, Antonio Molina-Carballo, Irene Machado-Casas, Luisa Fernández-López, Sylvia Martínez-Serrano, Pilar Tortosa-Pinto, Aida Ruiz-López, Juan-de-Dios Luna-del-Castillo, José Uberos and Antonio Muñoz-Hoyos
Int. J. Mol. Sci. 2014, 15(9), 17115-17129; https://doi.org/10.3390/ijms150917115 - 25 Sep 2014
Cited by 11 | Viewed by 7153
Abstract
The vast majority of Attention-deficit/hyperactivity disorder (ADHD) patients have other associated pathologies, with depressive symptoms as one of the most prevalent. Among the mediators that may participate in ADHD, melatonin is thought to regulate circadian rhythms, neurological function and stress response. To determine [...] Read more.
The vast majority of Attention-deficit/hyperactivity disorder (ADHD) patients have other associated pathologies, with depressive symptoms as one of the most prevalent. Among the mediators that may participate in ADHD, melatonin is thought to regulate circadian rhythms, neurological function and stress response. To determine (1) the serum baseline daily variations and nocturnal excretion of melatonin in ADHD subtypes and (2) the effect of chronic administration of methylphenidate, as well as the effects on symptomatology, 136 children with ADHD (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision: DSM-IV-TR criteria) were divided into subgroups using the “Children’s Depression Inventory” (CDI). Blood samples were drawn at 20:00 and 09:00 h, and urine was collected between 21:00 and 09:00 h, at inclusion and after 4.61 ± 2.29 months of treatment. Melatonin and its urine metabolite were measured by radioimmunoassay RIA. Factorial analysis was performed using STATA 12.0. Melatonin was higher predominantly in hyperactive-impulsive/conduct disordered children (PHI/CD) of the ADHD subtype, without the influence of comorbid depressive symptoms. Methylphenidate ameliorated this comorbidity without induction of any changes in the serum melatonin profile, but treatment with it was associated with a decrease in 6-s-melatonin excretion in both ADHD subtypes. Conclusions: In untreated children, partial homeostatic restoration of disrupted neuroendocrine equilibrium most likely led to an increased serum melatonin in PHI/CD children. A differential cerebral melatonin metabolization after methylphenidate may underlie some of the clinical benefit. Full article
(This article belongs to the Special Issue Advances in the Research of Melatonin 2014)
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Article
Abnormal Response of the Proliferation and Differentiation of Growth Plate Chondrocytes to Melatonin in Adolescent Idiopathic Scoliosis
by William Wei-Jun Wang, Gene Chi-Wai Man, Jack Ho Wong, Tzi-Bun Ng, Kwong-Man Lee, Bobby Kin-Wah Ng, Hiu-Yan Yeung, Yong Qiu and Jack Chun-Yiu Cheng
Int. J. Mol. Sci. 2014, 15(9), 17100-17114; https://doi.org/10.3390/ijms150917100 - 25 Sep 2014
Cited by 31 | Viewed by 7134
Abstract
Abnormalities in the melatonin signaling pathway and the involvement of melatonin receptor MT2 have been reported in patients with adolescent idiopathic scoliosis (AIS). Whether these abnormalities were involved in the systemic abnormal skeletal growth in AIS during the peripubertal period remain unknown. In [...] Read more.
Abnormalities in the melatonin signaling pathway and the involvement of melatonin receptor MT2 have been reported in patients with adolescent idiopathic scoliosis (AIS). Whether these abnormalities were involved in the systemic abnormal skeletal growth in AIS during the peripubertal period remain unknown. In this cross-sectional case-control study, growth plate chondrocytes (GPCs) were cultured from twenty AIS and ten normal control subjects. Although the MT2 receptor was identified in GPCs from both AIS and controls, its mRNA expression was significantly lower in AIS patients than the controls. GPCs were cultured in the presence of either the vehicle or various concentrations of melatonin, with or without the selective MT2 melatonin receptor antagonist 4-P-PDOT (10 µM). Then the cell viability and the mRNA expression of collagen type X (COLX) and alkaline phosphatase (ALP) were assessed by MTT and qPCR, respectively. In the control GPCs, melatonin at the concentrations of 1, 100 nM and 10 µM significantly reduced the population of viable cells, and the mRNA level of COLX and ALP compared to the vehicle. Similar changes were not observed in the presence of 4-P-PDOT. Further, neither proliferation nor differentiation of GPCs from AIS patients was affected by the melatonin treatment. These findings support the presence of a functional abnormality of the melatonin signaling pathway in AIS GPCs, which might be associated with the abnormal endochondral ossification in AIS patients. Full article
(This article belongs to the Special Issue Advances in the Research of Melatonin 2014)
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Article
Triethanolamine Stabilization of Methotrexate-β-Cyclodextrin Interactions in Ternary Complexes
by Jahamunna A. A. Barbosa, Ariana Zoppi, Mario A. Quevedo, Polyanne N. De Melo, Arthur S. A. De Medeiros, Letícia Streck, Alice R. De Oliveira, Matheus F. Fernandes-Pedrosa, Marcela R. Longhi and Arnóbio A. Da Silva-Júnior
Int. J. Mol. Sci. 2014, 15(9), 17077-17099; https://doi.org/10.3390/ijms150917077 - 25 Sep 2014
Cited by 40 | Viewed by 7829
Abstract
The interaction of methotrexate (MTX) with beta-cyclodextrin (β-CD) in the presence of triethanolamine (TEA) was investigated with the aim to elucidate the mechanism whereby self-assembly cyclodextrin systems work in association with this third component. Solubility diagram studies showed synergic increment of the MTX [...] Read more.
The interaction of methotrexate (MTX) with beta-cyclodextrin (β-CD) in the presence of triethanolamine (TEA) was investigated with the aim to elucidate the mechanism whereby self-assembly cyclodextrin systems work in association with this third component. Solubility diagram studies showed synergic increment of the MTX solubility to be about thirty-fold. Experiments using 2D ROESY and molecular modeling studies revealed the inclusion of aromatic ring III of the drug into β-CD cavity, in which TEA contributes by intensifying MTX interaction with β-CD and stabilizes MTX:β-CD:TEA ternary complex by electrostatic interaction. The maintenance of these interactions in solid phase was also studied in ternary MTX:β-CD:TEA and comparisons were made with freeze dried binary MTX:β-CD and physical mixtures. FTIR studies evidenced that MTX–β-CD interaction remained in solid ternary complexes, which was also supported by thermal (differential scanning calorimetry (DSC), thermogravimetric analysis (TG)/first derivative of TG analysis (DTG) and C,N,H elementary analysis) and structural (X-ray diffraction analysis, (XRD)) studies, mainly regarding the increment of drug stability. The efficient in vitro drug dissolution studies successfully demonstrated the contribution of ternary complexes, which highlights the importance of this possible new raw material for further applications in drug delivery systems. Full article
(This article belongs to the Section Materials Science)
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Article
SMG1 Acts as a Novel Potential Tumor Suppressor with Epigenetic Inactivation in Acute Myeloid Leukemia
by Yahui Du, Fei Lu, Peng Li, Jingjing Ye, Min Ji, Daoxin Ma and Chunyan Ji
Int. J. Mol. Sci. 2014, 15(9), 17065-17076; https://doi.org/10.3390/ijms150917065 - 25 Sep 2014
Cited by 24 | Viewed by 6484
Abstract
Suppressor with morphogenetic effect on genitalia family member (SMG1) belongs to a family of phosphoinositide 3-kinase-related kinases and is the main kinase involved in nonsense-mediated mRNA decay. Recently, SMG1 was suggested as a novel potential tumor suppressor gene, particularly in hypoxic tumors. To [...] Read more.
Suppressor with morphogenetic effect on genitalia family member (SMG1) belongs to a family of phosphoinositide 3-kinase-related kinases and is the main kinase involved in nonsense-mediated mRNA decay. Recently, SMG1 was suggested as a novel potential tumor suppressor gene, particularly in hypoxic tumors. To investigate the function of SMG1 in acute myeloid leukemia (AML), we performed methylation-specific polymerase chain reaction and found that SMG1 was hypermethylated in the promoter region. SMG1 hypermethylation was found in 66% (33/50) of AML samples compared with none (0/14) of the normal controls. SMG1 mRNA was down-regulated in AML patients with hypermethylation status whereas it was readily expressed in patients without methylation. Moreover, treatment of AML cells with demethylating agent 5-aza-2'-deoxycytidine (decitabine) inhibited AML cell growth and induced apoptosis by reversing SMG1 methylation status and restoring SMG1 expression. On the other hand, knockdown of SMG1 by RNA interference inhibited apoptosis. We also found that mTOR expression level was negatively correlated to SMG1 expression in AML patients which indicated that SMG1 and mTOR maybe act antagonistically to regulate AML cell growth. In conclusion, our results indicate that SMG1 acts as a potential tumor suppressor with epigenetic regulation in AML. Full article
(This article belongs to the Section Biochemistry)
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Article
Prediction of Multi-Target Networks of Neuroprotective Compounds with Entropy Indices and Synthesis, Assay, and Theoretical Study of New Asymmetric 1,2-Rasagiline Carbamates
by Francisco J. Romero Durán, Nerea Alonso, Olga Caamaño, Xerardo García-Mera, Matilde Yañez, Francisco J. Prado-Prado and Humberto González-Díaz
Int. J. Mol. Sci. 2014, 15(9), 17035-17064; https://doi.org/10.3390/ijms150917035 - 24 Sep 2014
Cited by 32 | Viewed by 7256
Abstract
In a multi-target complex network, the links (Lij) represent the interactions between the drug (di) and the target (tj), characterized by different experimental measures (Ki, Km, IC50, [...] Read more.
In a multi-target complex network, the links (Lij) represent the interactions between the drug (di) and the target (tj), characterized by different experimental measures (Ki, Km, IC50, etc.) obtained in pharmacological assays under diverse boundary conditions (cj). In this work, we handle Shannon entropy measures for developing a model encompassing a multi-target network of neuroprotective/neurotoxic compounds reported in the CHEMBL database. The model predicts correctly >8300 experimental outcomes with Accuracy, Specificity, and Sensitivity above 80%–90% on training and external validation series. Indeed, the model can calculate different outcomes for >30 experimental measures in >400 different experimental protocolsin relation with >150 molecular and cellular targets on 11 different organisms (including human). Hereafter, we reported by the first time the synthesis, characterization, and experimental assays of a new series of chiral 1,2-rasagiline carbamate derivatives not reported in previous works. The experimental tests included: (1) assay in absence of neurotoxic agents; (2) in the presence of glutamate; and (3) in the presence of H2O2. Lastly, we used the new Assessing Links with Moving Averages (ALMA)-entropy model to predict possible outcomes for the new compounds in a high number of pharmacological tests not carried out experimentally. Full article
(This article belongs to the Special Issue Molecular Science for Drug Development and Biomedicine)
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1779 KiB  
Communication
PACAP38 Differentially Effects Genes and CRMP2 Protein Expression in Ischemic Core and Penumbra Regions of Permanent Middle Cerebral Artery Occlusion Model Mice Brain
by Motohide Hori, Tomoya Nakamachi, Junko Shibato, Randeep Rakwal, Masachi Tsuchida, Seiji Shioda and Satoshi Numazawa
Int. J. Mol. Sci. 2014, 15(9), 17014-17034; https://doi.org/10.3390/ijms150917014 - 23 Sep 2014
Cited by 17 | Viewed by 9206
Abstract
Pituitary adenylate-cyclase activating polypeptide (PACAP) has neuroprotective and axonal guidance functions, but the mechanisms behind such actions remain unclear. Previously we examined effects of PACAP (PACAP38, 1 pmol) injection intracerebroventrically in a mouse model of permanent middle cerebral artery occlusion (PMCAO) along with [...] Read more.
Pituitary adenylate-cyclase activating polypeptide (PACAP) has neuroprotective and axonal guidance functions, but the mechanisms behind such actions remain unclear. Previously we examined effects of PACAP (PACAP38, 1 pmol) injection intracerebroventrically in a mouse model of permanent middle cerebral artery occlusion (PMCAO) along with control saline (0.9% NaCl) injection. Transcriptomic and proteomic approaches using ischemic (ipsilateral) brain hemisphere revealed differentially regulated genes and proteins by PACAP38 at 6 and 24 h post-treatment. However, as the ischemic hemisphere consisted of infarct core, penumbra, and non-ischemic regions, specificity of expression and localization of these identified molecular factors remained incomplete. This led us to devise a new experimental strategy wherein, ischemic core and penumbra were carefully sampled and compared to the corresponding contralateral (healthy) core and penumbra regions at 6 and 24 h post PACAP38 or saline injections. Both reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting were used to examine targeted gene expressions and the collapsin response mediator protein 2 (CRMP2) protein profiles, respectively. Clear differences in expression of genes and CRMP2 protein abundance and degradation product/short isoform was observed between ischemic core and penumbra and also compared to the contralateral healthy tissues after PACAP38 or saline treatment. Results indicate the importance of region-specific analyses to further identify, localize and functionally analyse target molecular factors for clarifying the neuroprotective function of PACAP38. Full article
(This article belongs to the Special Issue Neurological Injuries’ Monitoring, Tracking and Treatment)
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2653 KiB  
Article
Function of SREBP1 in the Milk Fat Synthesis of Dairy Cow Mammary Epithelial Cells
by Nan Li, Feng Zhao, Chenjie Wei, Mengyao Liang, Na Zhang, Chunmei Wang, Qing-Zhang Li and Xue-Jun Gao
Int. J. Mol. Sci. 2014, 15(9), 16998-17013; https://doi.org/10.3390/ijms150916998 - 23 Sep 2014
Cited by 101 | Viewed by 9154
Abstract
Sterol regulatory element-binding proteins (SREBPs) belong to a family of nuclear transcription factors. The question of which is the most important positive regulator in milk fat synthesis in dairy cow mammary epithelial cells (DCMECs) between SREBPs or other nuclear transcription factors, such as [...] Read more.
Sterol regulatory element-binding proteins (SREBPs) belong to a family of nuclear transcription factors. The question of which is the most important positive regulator in milk fat synthesis in dairy cow mammary epithelial cells (DCMECs) between SREBPs or other nuclear transcription factors, such as peroxisome proliferator-activated receptor γ (PPARγ), remains a controversial one. Recent studies have found that mTORC1 (the mammalian target of rapamycin C1) regulates SREBP1 to promote fat synthesis. Thus far, however, the interaction between the SREBP1 and mTOR (the mammalian target of rapamycin) pathways in the regulation of milk fat synthesis remains poorly understood. This study aimed to identify the function of SREBP1 in milk fat synthesis and to characterize the relationship between SREBP1 and mTOR in DCMECs. The effects of SREBP1 overexpression and gene silencing on milk fat synthesis and the effects of stearic acid and serum on SREBP1 expression in the upregulation of milk fat synthesis were investigated in DCMECs using immunostaining, Western blotting, real-time quantitative PCR, lipid droplet staining, and detection kits for triglyceride content. SREBP1 was found to be a positive regulator of milk fat synthesis and was shown to be regulated by stearic acid and serum. These findings indicate that SREBP1 is the key positive regulator in milk fat synthesis. Full article
(This article belongs to the Section Biochemistry)
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2443 KiB  
Review
The Role of 8-Oxoguanine DNA Glycosylase-1 in Inflammation
by Xueqing Ba, Leopoldo Aguilera-Aguirre, Qura Tul Ain Nmi Rashid, Attila Bacsi, Zsolt Radak, Sanjiv Sur, Koa Hosoki, Muralidhar L. Hegde and Istvan Boldogh
Int. J. Mol. Sci. 2014, 15(9), 16975-16997; https://doi.org/10.3390/ijms150916975 - 23 Sep 2014
Cited by 91 | Viewed by 16034
Abstract
Many, if not all, environmental pollutants/chemicals and infectious agents increase intracellular levels of reactive oxygen species (ROS) at the site of exposure. ROS not only function as intracellular signaling entities, but also induce damage to cellular molecules including DNA. Among the several dozen [...] Read more.
Many, if not all, environmental pollutants/chemicals and infectious agents increase intracellular levels of reactive oxygen species (ROS) at the site of exposure. ROS not only function as intracellular signaling entities, but also induce damage to cellular molecules including DNA. Among the several dozen ROS-induced DNA base lesions generated in the genome, 8-oxo-7,8-dihydroguanine (8-oxoG) is one of the most abundant because of guanine’s lowest redox potential among DNA bases. In mammalian cells, 8-oxoG is repaired by the 8-oxoguanine DNA glycosylase-1 (OGG1)-initiated DNA base excision repair pathway (OGG1–BER). Accumulation of 8-oxoG in DNA has traditionally been associated with mutagenesis, as well as various human diseases and aging processes, while the free 8-oxoG base in body fluids is one of the best biomarkers of ongoing pathophysiological processes. In this review, we discuss the biological significance of the 8-oxoG base and particularly the role of OGG1–BER in the activation of small GTPases and changes in gene expression, including those that regulate pro-inflammatory chemokines/cytokines and cause inflammation. Full article
(This article belongs to the Special Issue DNA Damage and Repair in Degenerative Diseases 2014)
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Article
Association of Allelic Variation in PtoXET16A with Growth and Wood Properties in Populus tomentosa
by Bowen Wang and Deqiang Zhang
Int. J. Mol. Sci. 2014, 15(9), 16949-16974; https://doi.org/10.3390/ijms150916949 - 23 Sep 2014
Cited by 7 | Viewed by 5480
Abstract
Xyloglucan endo-transglycosylases (XETs) modify the xyloglucan-cellulose framework of plant cell walls and, thus, affect cell wall expansion and strength. Dissecting the mechanism by which natural variation in XETs affects wood properties can inform breeding efforts to improve wood quality and yield traits. [...] Read more.
Xyloglucan endo-transglycosylases (XETs) modify the xyloglucan-cellulose framework of plant cell walls and, thus, affect cell wall expansion and strength. Dissecting the mechanism by which natural variation in XETs affects wood properties can inform breeding efforts to improve wood quality and yield traits. To this end, we isolated a full-length PtoXET16A cDNA clone from Populus tomentosa. Real-time PCR analysis showed that PtoXET16A was maximally expressed in the root, followed by phloem, cambium, and developing xylem, suggesting that PtoXET16A plays important roles in the development of vascular tissues. Nucleotide diversity and linkage disequilibrium analysis revealed that PtoXET16A has high single nucleotide polymorphism (SNP) diversity (π = 0.01266 and θw = 0.01392) and low linkage disequilibrium (r2 ≥ 0.1, within 900 bp). SNP- and haplotype-based association analyses of 426 individuals from a natural population indicated that nine SNPs (including two non-synonymous markers and one splicing variant) (p ≤ 0.05, false discovery rate Q ≤ 0.01), and nine haplotypes (p ≤ 0.05) were significantly associated with growth and wood properties, each explaining from 3.40%–10.95% of phenotypic variance. This work shows that examination of allelic variation and linkage disequilibrium by a candidate-gene-based approach can help to decipher the genetic basis of wood formation. Moreover, the SNP markers identified in this study can potentially be applied for marker-assisted selection to improve growth and wood-property traits in Populus. Full article
(This article belongs to the Section Biochemistry)
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Article
Emodin-Loaded Magnesium Silicate Hollow Nanocarriers for Anti-Angiogenesis Treatment through Inhibiting VEGF
by Hua Ren, Chao Zhu, Zhaohui Li, Wei Yang and E Song
Int. J. Mol. Sci. 2014, 15(9), 16936-16948; https://doi.org/10.3390/ijms150916936 - 23 Sep 2014
Cited by 19 | Viewed by 7067
Abstract
The applications of anti-VEGF (vascular endothelial growth factor) treatment in ophthalmic fields to inhibit angiogenesis have been widely documented in recent years. However, the hydrophobic nature of many agents makes its delivery difficult in practice. Therefore, the aim of the present study was [...] Read more.
The applications of anti-VEGF (vascular endothelial growth factor) treatment in ophthalmic fields to inhibit angiogenesis have been widely documented in recent years. However, the hydrophobic nature of many agents makes its delivery difficult in practice. Therefore, the aim of the present study was to introduce a new kind of hydrophobic drug carrier by employing nanoparticles with a hollow structure inside. Followed by the synthesis and characterization of magnesium silicate hollow spheres, cytotoxicity was evaluated in retina capillary endothelial cells. The loading and releasing capacity were tested by employing emodin, and the effect on VEGF expression was performed at the gene and protein level. Finally, an investigation on angiogenesis was carried on fertilized chicken eggs. The results indicated that the magnesium silicate nanoparticles had low toxicity. Emodin–MgSiO3 can inhibit the expression of both VEGF gene and protein effectively. Angiogenesis of eggs was also reduced significantly. Based on the above results, we concluded that magnesium silicate hollow spheres were good candidates as drug carriers with enough safety. Full article
(This article belongs to the Special Issue Bioactive Nanoparticles 2014)
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Article
Anticonvulsant Profiles of Certain New 6-Aryl-9-substituted-6,9-diazaspiro-[4.5]decane-8,10-diones and 1-Aryl-4-substituted-1,4-diazaspiro[5.5]undecane-3,5-diones
by Mohamed N. Aboul-Enein, Aida A. El-Azzouny, Mohamed I. Attia, Yousreya A. Maklad, Mona E. Aboutabl, Fatma Ragab and Walaa H. A. Abd El-Hamid
Int. J. Mol. Sci. 2014, 15(9), 16911-16935; https://doi.org/10.3390/ijms150916911 - 23 Sep 2014
Cited by 13 | Viewed by 5403
Abstract
Synthesis and anticonvulsant potential of certain new 6-aryl-9-substituted-6,9-diazaspiro[4.5]decane-8,10-diones (6al) and 1-aryl-4-substituted-1,4-diazaspiro[5.5] undecane-3,5-diones (6mx) are reported. The intermediates 1-[(aryl)(cyanomethyl)amino] cycloalkanecarboxamides (3af) were prepared via adopting Strecker synthesis on the proper cycloalkanone followed [...] Read more.
Synthesis and anticonvulsant potential of certain new 6-aryl-9-substituted-6,9-diazaspiro[4.5]decane-8,10-diones (6al) and 1-aryl-4-substituted-1,4-diazaspiro[5.5] undecane-3,5-diones (6mx) are reported. The intermediates 1-[(aryl)(cyanomethyl)amino] cycloalkanecarboxamides (3af) were prepared via adopting Strecker synthesis on the proper cycloalkanone followed by partial hydrolysis of the obtained nitrile functionality and subsequent N-cyanomethylation. Compounds 3af were subjected to complete nitrile hydrolysis to give the respective carboxylic acid derivatives 4af which were cyclized under mild conditions to give the spiro compounds 5af. Ultimately, compounds 5af were alkylated or aralkylated to give the target compounds 6ai and 6mu. On the other hand, compounds 6jl and 6vx were synthesized from the intermediates 5af through alkylation, dehydration and finally tetrazole ring formation. Anticonvulsant screening of the target compounds 6ax revealed that compound 6g showed an ED50 of 0.0043 mmol/kg in the scPTZ screen, being about 14 and 214 fold more potent than the reference drugs, Phenobarbital (ED50 = 0.06 mmol/kg) and Ethosuximide (ED50 = 0.92 mmol/kg), respectively. Compound 6e exhibited an ED50 of 0.019 mmol/kg, being about 1.8 fold more potent than that of the reference drug, Diphenylhydantoin (ED50 = 0.034 mmol/kg) in the MES screen. Interestingly, all the test compounds 6ax did not show any minimal motor impairment at the maximum administered dose in the neurotoxicity screen. Full article
(This article belongs to the Section Biochemistry)
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Article
Biochemical Characterization of a Carboxylesterase from the Archaeon Pyrobaculum sp. 1860 and a Rational Explanation of Its Substrate Specificity and Thermostability
by Hua Shao, Li Xu and Yunjun Yan
Int. J. Mol. Sci. 2014, 15(9), 16885-16910; https://doi.org/10.3390/ijms150916885 - 23 Sep 2014
Cited by 17 | Viewed by 6666
Abstract
In this work, genome mining was used to identify esterase/lipase genes in the archaeon Pyrobaculum sp. 1860. A gene was cloned and functionally expressed in Escherichia coli as His-tagged protein. The recombinant enzyme (rP186_1588) was verified by western blotting and peptide mass fingerprinting. [...] Read more.
In this work, genome mining was used to identify esterase/lipase genes in the archaeon Pyrobaculum sp. 1860. A gene was cloned and functionally expressed in Escherichia coli as His-tagged protein. The recombinant enzyme (rP186_1588) was verified by western blotting and peptide mass fingerprinting. Biochemical characterization revealed that rP186_1588 exhibited optimum activity at pH 9.0 and 80 °C towards p-nitrophenyl acetate (Km: 0.35 mM, kcat: 11.65 s−1). Interestingly, the purified rP186_1588 exhibited high thermostability retaining 70% relative activity after incubation at 90 °C for 6 h. Circular dichroism results indicated that rP186_1588 showed slight structure alteration from 60 to 90 °C. Structural modeling showed P186_1588 possessed a typical α/β hydrolase’s fold with the catalytic triad consisting of Ser97, Asp147 and His172, and was further confirmed by site-directed mutagenesis. Comparative molecular simulations at different temperatures (300, 353, 373 and 473 K) revealed that its thermostability was associated with its conformational rigidity. The binding free energy analysis by MM-PBSA method revealed that the van der Waals interaction played a major role in p-NP ester binding for P186_1588. Our data provide insights into the molecular structures of this archaeal esterase, and may help to its further protein engineering for industrial applications. Full article
(This article belongs to the Section Biochemistry)
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Review
Melatonin Regulates Aging and Neurodegeneration through Energy Metabolism, Epigenetics, Autophagy and Circadian Rhythm Pathways
by Anorut Jenwitheesuk, Chutikorn Nopparat, Sujira Mukda, Prapimpun Wongchitrat and Piyarat Govitrapong
Int. J. Mol. Sci. 2014, 15(9), 16848-16884; https://doi.org/10.3390/ijms150916848 - 22 Sep 2014
Cited by 125 | Viewed by 21027
Abstract
Brain aging is linked to certain types of neurodegenerative diseases and identifying new therapeutic targets has become critical. Melatonin, a pineal hormone, associates with molecules and signaling pathways that sense and influence energy metabolism, autophagy, and circadian rhythms, including insulin-like growth factor 1 [...] Read more.
Brain aging is linked to certain types of neurodegenerative diseases and identifying new therapeutic targets has become critical. Melatonin, a pineal hormone, associates with molecules and signaling pathways that sense and influence energy metabolism, autophagy, and circadian rhythms, including insulin-like growth factor 1 (IGF-1), Forkhead box O (FoxOs), sirtuins and mammalian target of rapamycin (mTOR) signaling pathways. This review summarizes the current understanding of how melatonin, together with molecular, cellular and systemic energy metabolisms, regulates epigenetic processes in the neurons. This information will lead to a greater understanding of molecular epigenetic aging of the brain and anti-aging mechanisms to increase lifespan under healthy conditions. Full article
(This article belongs to the Special Issue Advances in the Research of Melatonin 2014)
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Article
Synthesis, Characterization and in Vitro Evaluation of New Composite Bisphosphonate Delivery Systems
by Joanna Kolmas, Marcin Sobczak, Ewa Olędzka, Grzegorz Nałęcz-Jawecki and Cezary Dębek
Int. J. Mol. Sci. 2014, 15(9), 16831-16847; https://doi.org/10.3390/ijms150916831 - 22 Sep 2014
Cited by 12 | Viewed by 6591
Abstract
In this study, new composite bisphosphonate delivery systems were obtained from polyurethanes (PUs) and nanocrystalline hydroxyapatite (HA). The biodegradable PUs were first synthesized from poly(ε-caprolactone) diols (PCL diols), poly(ethylene adipate) diol, 1,6-hexamethylene diisocyanate, 1,4-butanediol and HA. Moreover, the PCL diols were synthesized by [...] Read more.
In this study, new composite bisphosphonate delivery systems were obtained from polyurethanes (PUs) and nanocrystalline hydroxyapatite (HA). The biodegradable PUs were first synthesized from poly(ε-caprolactone) diols (PCL diols), poly(ethylene adipate) diol, 1,6-hexamethylene diisocyanate, 1,4-butanediol and HA. Moreover, the PCL diols were synthesized by the ring-opening polymerization catalysed by the lipase from Candida antarctica. Next, composite drug delivery systems for clodronate were prepared. The mechanical properties of the obtained biomaterials were determined. The cytotoxicity of the synthesized polymers was tested. The preliminary results show that the obtained composites are perspective biomaterials and they can be potentially applied in the technology of implantation drug delivery systems. Full article
(This article belongs to the Special Issue Biomimetic and Functional Materials)
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Review
Brain Metastases in Gastrointestinal Cancers: Is there a Role for Surgery?
by Johannes Lemke, Jan Scheele, Thomas Kapapa, Silvia Von Karstedt, Christian Rainer Wirtz, Doris Henne-Bruns and Marko Kornmann
Int. J. Mol. Sci. 2014, 15(9), 16816-16830; https://doi.org/10.3390/ijms150916816 - 22 Sep 2014
Cited by 22 | Viewed by 7712
Abstract
About 10% of all cancer patients will develop brain metastases during advanced disease progression. Interestingly, the vast majority of brain metastases occur in only three types of cancer: Melanoma, lung and breast cancer. In this review, we focus on summarizing the prognosis and [...] Read more.
About 10% of all cancer patients will develop brain metastases during advanced disease progression. Interestingly, the vast majority of brain metastases occur in only three types of cancer: Melanoma, lung and breast cancer. In this review, we focus on summarizing the prognosis and impact of surgical resection of brain metastases originating from gastrointestinal cancers such as esophageal, gastric, pancreatic and colorectal cancer. The incidence of brain metastases is <1% in pancreatic and gastric cancer and <4% in esophageal and colorectal cancer. Overall, prognosis of these patients is very poor with a median survival in the range of only months. Interestingly, a substantial number of patients who had received surgical resection of brain metastases showed prolonged survival. However, it should be taken into account that all these studies were not randomized and it is likely that patients selected for surgical treatment presented with other important prognostic factors such as solitary brain metastases and exclusion of extra-cranial disease. Nevertheless, other reports have demonstrated long-term survival of patients upon resection of brain metastases originating from gastrointestinal cancers. Thus, it appears to be justified to consider aggressive surgical approaches for these patients. Full article
(This article belongs to the Special Issue Brain Metastasis 2014)
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Article
Mycophenolate Antagonizes IFN-γ-Induced Catagen-Like Changes via β-Catenin Activation in Human Dermal Papilla Cells and Hair Follicles
by Sunhyo Ryu, Yonghee Lee, Moo Yeol Hyun, Sun Young Choi, Kwan Ho Jeong, Young Min Park, Hoon Kang, Kui Young Park, Cheryl A. Armstrong, Andrew Johnson, Peter I. Song and Beom Joon Kim
Int. J. Mol. Sci. 2014, 15(9), 16800-16815; https://doi.org/10.3390/ijms150916800 - 22 Sep 2014
Cited by 13 | Viewed by 10733
Abstract
Recently, various immunosuppressant drugs have been shown to induce hair growth in normal hair as well as in alopecia areata and androgenic alopecia; however, the responsible mechanism has not yet been fully elucidated. In this study, we investigate the influence of mycophenolate (MPA), [...] Read more.
Recently, various immunosuppressant drugs have been shown to induce hair growth in normal hair as well as in alopecia areata and androgenic alopecia; however, the responsible mechanism has not yet been fully elucidated. In this study, we investigate the influence of mycophenolate (MPA), an immunosuppressant, on the proliferation of human dermal papilla cells (hDPCs) and on the growth of human hair follicles following catagen induction with interferon (IFN)-γ. IFN-γ was found to reduce β-catenin, an activator of hair follicle growth, and activate glycogen synthase kinase (GSK)-3β, and enhance expression of the Wnt inhibitor DKK-1 and catagen inducer transforming growth factor (TGF)-β2. IFN-γ inhibited expression of ALP and other dermal papillar cells (DPCs) markers such as Axin2, IGF-1, and FGF 7 and 10. MPA increased β-catenin in IFN-γ-treated hDPCs leading to its nuclear accumulation via inhibition of GSK3β and reduction of DKK-1. Furthermore, MPA significantly increased expression of ALP and other DPC marker genes but inhibited expression of TGF-β2. Therefore, we demonstrate for the first time that IFN-γ induces catagen-like changes in hDPCs and in hair follicles via inhibition of Wnt/β-catenin signaling, and that MPA stabilizes β-catenin by inhibiting GSK3β leading to increased β-catenin target gene and DP signature gene expression, which may, in part, counteract IFN-γ-induced catagen in hDPCs. Full article
(This article belongs to the Special Issue Pharmaceuticals and Nutraceuticals by Molecular Farming)
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Article
Metabolism of Cryptic Peptides Derived from Neuropeptide FF Precursors: The Involvement of Insulin-Degrading Enzyme
by Giuseppe Grasso, Przemyslaw Mielczarek, Magdalena Niedziolka and Jerzy Silberring
Int. J. Mol. Sci. 2014, 15(9), 16787-16799; https://doi.org/10.3390/ijms150916787 - 22 Sep 2014
Cited by 17 | Viewed by 6670
Abstract
The term “cryptome” refers to the subset of cryptic peptides with bioactivities that are often unpredictable and very different from the parent protein. These cryptic peptides are generated by proteolytic cleavage of proteases, whose identification in vivo can be very challenging. In this [...] Read more.
The term “cryptome” refers to the subset of cryptic peptides with bioactivities that are often unpredictable and very different from the parent protein. These cryptic peptides are generated by proteolytic cleavage of proteases, whose identification in vivo can be very challenging. In this work, we show that insulin-degrading enzyme (IDE) is able to degrade specific amino acid sequences present in the neuropeptide pro-NPFFA (NPFF precursor), generating some cryptic peptides that are also observed after incubation with rat brain cortex homogenate. The reported experimental findings support the increasingly accredited hypothesis, according to which, due to its wide substrate selectivity, IDE is involved in a wide variety of physiopathological processes. Full article
(This article belongs to the Special Issue Proteins and Protein-Ligand Interactions)
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Article
Electricity Generation and Wastewater Treatment of Oil Refinery in Microbial Fuel Cells Using Pseudomonas putida
by Dip Majumder, Jyoti Prakash Maity, Min-Jen Tseng, Vanita Roshan Nimje, Hau-Ren Chen, Chien-Cheng Chen, Young-Fo Chang, Tsui-Chu Yang and Chen-Yen Chen
Int. J. Mol. Sci. 2014, 15(9), 16772-16786; https://doi.org/10.3390/ijms150916772 - 22 Sep 2014
Cited by 60 | Viewed by 8219
Abstract
Microbial fuel cells (MFCs) represent a novel platform for treating wastewater and at the same time generating electricity. Using Pseudomonas putida (BCRC 1059), a wild-type bacterium, we demonstrated that the refinery wastewater could be treated and also generate electric current [...] Read more.
Microbial fuel cells (MFCs) represent a novel platform for treating wastewater and at the same time generating electricity. Using Pseudomonas putida (BCRC 1059), a wild-type bacterium, we demonstrated that the refinery wastewater could be treated and also generate electric current in an air-cathode chamber over four-batch cycles for 63 cumulative days. Our study indicated that the oil refinery wastewater containing 2213 mg/L (ppm) chemical oxygen demand (COD) could be used as a substrate for electricity generation in the reactor of the MFC. A maximum voltage of 355 mV was obtained with the highest power density of 0.005 mW/cm2 in the third cycle with a maximum current density of 0.015 mA/cm2 in regard to the external resistor of 1000 Ω. A maximum coulombic efficiency of 6 × 10−2% was obtained in the fourth cycle. The removal efficiency of the COD reached 30% as a function of time. Electron transfer mechanism was studied using cyclic voltammetry, which indicated the presence of a soluble electron shuttle in the reactor. Our study demonstrated that oil refinery wastewater could be used as a substrate for electricity generation. Full article
(This article belongs to the Section Green Chemistry)
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Article
Two New Quinochalcone C-Glycosides from the Florets of Carthamus tinctorius
by Shijun Yue, Yuping Tang, Chengmei Xu, Shujiao Li, Yue Zhu and Jin-Ao Duan
Int. J. Mol. Sci. 2014, 15(9), 16760-16771; https://doi.org/10.3390/ijms150916760 - 22 Sep 2014
Cited by 28 | Viewed by 6512
Abstract
Two new quinochalcone C-glycosides, named hydroxysafflor yellow B (1) and hydroxysafflor yellow C (2), along with two known quinochalcone C-glycosides, safflomin C (3) and saffloquinoside C (4), and one known flavanone, (2R [...] Read more.
Two new quinochalcone C-glycosides, named hydroxysafflor yellow B (1) and hydroxysafflor yellow C (2), along with two known quinochalcone C-glycosides, safflomin C (3) and saffloquinoside C (4), and one known flavanone, (2R)-4',5-dihydroxyl-6, 7-di-O-β-d-glucopyranosyl flavanone (5), were isolated from the florets of Carthamus tinctorius. Their structures were determined by extensive spectroscopic (UV, IR, HR-ESI-MS, 1D and 2D NMR) analyses. In addition, these quinochalcone C-glycosides together with hydroxysafflor yellow A and anhydrosafflor yellow B were evaluated for their anti-oxidative effects against H2O2-induced cytotoxicity in cultured H9c2 cells. Among them, compound 2 exhibited significant anti-oxidative effects. Full article
(This article belongs to the Section Biochemistry)
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Article
Genetically Modified Flax Expressing NAP-SsGT1 Transgene: Examination of Anti-Inflammatory Action
by Magdalena Matusiewicz, Iwona Kosieradzka, Magdalena Zuk and Jan Szopa
Int. J. Mol. Sci. 2014, 15(9), 16741-16759; https://doi.org/10.3390/ijms150916741 - 22 Sep 2014
Cited by 6 | Viewed by 8420
Abstract
The aim of the work was to define the influence of dietary supplementation with GM (genetically modified) GT#4 flaxseed cake enriched in polyphenols on inflammation development in mice liver. Mice were given ad libitum isoprotein diets: (1) standard diet; (2) high-fat diet rich [...] Read more.
The aim of the work was to define the influence of dietary supplementation with GM (genetically modified) GT#4 flaxseed cake enriched in polyphenols on inflammation development in mice liver. Mice were given ad libitum isoprotein diets: (1) standard diet; (2) high-fat diet rich in lard, high-fat diet enriched with 30% of (3) isogenic flax Linola seed cake; and (4) GM GT#4 flaxseed cake; for 96 days. Administration of transgenic and isogenic seed cake lowered body weight gain, of transgenic to the standard diet level. Serum total antioxidant status was statistically significantly improved in GT#4 flaxseed cake group and did not differ from Linola. Serum thiobarbituric acid reactive substances, lipid profile and the liver concentration of pro-inflammatory cytokine tumor necrosis factor-α were ameliorated by GM and isogenic flaxseed cake consumption. The level of pro-inflammatory cytokine interferon-γ did not differ between mice obtaining GM GT#4 and non-GM flaxseed cakes. The C-reactive protein concentration was reduced in animals fed GT#4 flaxseed cake and did not differ from those fed non-GM flaxseed cake-based diet. Similarly, the liver structure of mice consuming diets enriched in flaxseed cake was improved. Dietetic enrichment with GM GT#4 and non-GM flaxseed cakes may be a promising solution for health problems resulting from improper diet. Full article
(This article belongs to the Special Issue Detection and Safety Assessment of Genetically Modified Organisms)
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Article
Sperm and Spermatids Contain Different Proteins and Bind Distinct Egg Factors
by Marta Teperek, Kei Miyamoto, Angela Simeone, Renata Feret, Michael J. Deery, John B. Gurdon and Jerome Jullien
Int. J. Mol. Sci. 2014, 15(9), 16719-16740; https://doi.org/10.3390/ijms150916719 - 19 Sep 2014
Cited by 3 | Viewed by 8118
Abstract
Spermatozoa are more efficient at supporting normal embryonic development than spermatids, their immature, immediate precursors. This suggests that the sperm acquires the ability to support embryonic development during spermiogenesis (spermatid to sperm maturation). Here, using Xenopus laevis as a model organism, we performed [...] Read more.
Spermatozoa are more efficient at supporting normal embryonic development than spermatids, their immature, immediate precursors. This suggests that the sperm acquires the ability to support embryonic development during spermiogenesis (spermatid to sperm maturation). Here, using Xenopus laevis as a model organism, we performed 2-D Fluorescence Difference Gel Electrophoresis (2D-DIGE) and mass spectrometry analysis of differentially expressed proteins between sperm and spermatids in order to identify factors that could be responsible for the efficiency of the sperm to support embryonic development. Furthermore, benefiting from the availability of egg extracts in Xenopus, we also tested whether the chromatin of sperm could attract different egg factors compared to the chromatin of spermatids. Our analysis identified: (1) several proteins which were present exclusively in sperm; but not in spermatid nuclei and (2) numerous egg proteins binding to the sperm (but not to the spermatid chromatin) after incubation in egg extracts. Amongst these factors we identified many chromatin-associated proteins and transcriptional repressors. Presence of transcriptional repressors binding specifically to sperm chromatin could suggest its preparation for the early embryonic cell cycles, during which no transcription is observed and suggests that sperm chromatin has a unique protein composition, which facilitates the recruitment of egg chromatin remodelling factors. It is therefore likely that the acquisition of these sperm-specific factors during spermiogenesis makes the sperm chromatin suitable to interact with the maternal factors and, as a consequence, to support efficient embryonic development. Full article
(This article belongs to the Special Issue Cellular and Molecular Mechanisms of Sperm-Egg Interaction)
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Review
Recent Progress on Liver Kinase B1 (LKB1): Expression, Regulation, Downstream Signaling and Cancer Suppressive Function
by Ren-You Gan and Hua-Bin Li
Int. J. Mol. Sci. 2014, 15(9), 16698-16718; https://doi.org/10.3390/ijms150916698 - 19 Sep 2014
Cited by 59 | Viewed by 9879
Abstract
Liver kinase B1 (LKB1), known as a serine/threonine kinase, has been identified as a critical cancer suppressor in many cancer cells. It is a master upstream kinase of 13 AMP-activated protein kinase (AMPK)-related protein kinases, and possesses versatile biological functions. LKB1 gene is [...] Read more.
Liver kinase B1 (LKB1), known as a serine/threonine kinase, has been identified as a critical cancer suppressor in many cancer cells. It is a master upstream kinase of 13 AMP-activated protein kinase (AMPK)-related protein kinases, and possesses versatile biological functions. LKB1 gene is mutated in many cancers, and its protein can form different protein complexes with different cellular localizations in various cell types. The expression of LKB1 can be regulated through epigenetic modification, transcriptional regulation and post-translational modification. LKB1 dowcnstream pathways mainly include AMPK, microtubule affinity regulating kinase (MARK), salt-inducible kinase (SIK), sucrose non-fermenting protein-related kinase (SNRK) and brain selective kinase (BRSK) signalings, etc. This review, therefore, mainly discusses recent studies about the expression, regulation, downstream signaling and cancer suppressive function of LKB1, which can be helpful for better understanding of this molecular and its significance in cancers. Full article
(This article belongs to the Section Biochemistry)
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Review
Diversity in TAF Proteomics: Consequences for Cellular Differentiation and Migration
by Jekaterina Kazantseva and Kaia Palm
Int. J. Mol. Sci. 2014, 15(9), 16680-16697; https://doi.org/10.3390/ijms150916680 - 19 Sep 2014
Cited by 11 | Viewed by 11020
Abstract
Development is a highly controlled process of cell proliferation and differentiation driven by mechanisms of dynamic gene regulation. Specific DNA binding factors for establishing cell- and tissue-specific transcriptional programs have been characterised in different cell and animal models. However, much less is known [...] Read more.
Development is a highly controlled process of cell proliferation and differentiation driven by mechanisms of dynamic gene regulation. Specific DNA binding factors for establishing cell- and tissue-specific transcriptional programs have been characterised in different cell and animal models. However, much less is known about the role of “core transcription machinery” during cell differentiation, given that general transcription factors and their spatiotemporally patterned activity govern different aspects of cell function. In this review, we focus on the role of TATA-box associated factor 4 (TAF4) and its functional isoforms generated by alternative splicing in controlling lineage-specific differentiation of normal mesenchymal stem cells and cancer stem cells. In the light of our recent findings, induction, control and maintenance of cell differentiation status implies diversification of the transcription initiation apparatus orchestrated by alternative splicing. Full article
(This article belongs to the Section Biochemistry)
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Communication
Inhibitory Effects of Adlay Extract on Melanin Production and Cellular Oxygen Stress in B16F10 Melanoma Cells
by Huey-Chun Huang, Wan-Yu Hsieh, Yu-Lin Niu and Tsong-Min Chang
Int. J. Mol. Sci. 2014, 15(9), 16665-16679; https://doi.org/10.3390/ijms150916665 - 19 Sep 2014
Cited by 39 | Viewed by 9710
Abstract
The aim of this study was to determine the effects of adlay extract on melanin production and the antioxidant characteristics of the extract. The seeds were extracted by the supercritical fluid CO2 extraction (SFE) method. The effect of adlay extract on melanin [...] Read more.
The aim of this study was to determine the effects of adlay extract on melanin production and the antioxidant characteristics of the extract. The seeds were extracted by the supercritical fluid CO2 extraction (SFE) method. The effect of adlay extract on melanin production was evaluated using mushroom tyrosinase activity assay, intracellular tyrosinase activity, antioxidant properties and melanin content. Those assays were performed spectrophotometrically. In addition, the expression of melanogenesis-related proteins was determined by western blotting. The results revealed that the adlay extract suppressed intracellular tyrosinase activity and decreased the amount of melanin in B16F10 cells. The adlay extract decreased the expression of microphthalmia-associated transcription factor (MITF), tyrosinase, tyrosinase related protein-1 (TRP-1) and tyrosinase related protein-2 (TRP-2). The extract also exhibited antioxidant characteristics such as free radical scavenging capacity and reducing power. It effectively decreased intracellular reactive oxygen species (ROS) levels in B16F10 cells. We concluded that the adlay extract inhibits melanin production by down-regulation of MITF, tyrosinase, TRP-1 and TRP-2. The antioxidant properties of the extract may also contribute to the inhibition of melanogenesis. The adlay extract can therefore be applied as an inhibitor of melanogenesis and could also act as a natural antioxidant in skin care products. Full article
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Article
Dexamethasone and 1,25-Dihydroxyvitamin D3 Reduce Oxidative Stress-Related DNA Damage in Differentiating Osteoblasts
by Elzbieta Pawlowska, Daniel Wysokiński, Paulina Tokarz, Agnieszka Piastowska-Ciesielska, Joanna Szczepanska and Janusz Blasiak
Int. J. Mol. Sci. 2014, 15(9), 16649-16664; https://doi.org/10.3390/ijms150916649 - 19 Sep 2014
Cited by 8 | Viewed by 6554
Abstract
The process of osteoblast differentiation is regulated by several factors, including RUNX2. Recent reports suggest an involvement of RUNX2 in DNA damage response (DDR), which is important due to association of differentiation with oxidative stress. In the present work we explore the influence [...] Read more.
The process of osteoblast differentiation is regulated by several factors, including RUNX2. Recent reports suggest an involvement of RUNX2 in DNA damage response (DDR), which is important due to association of differentiation with oxidative stress. In the present work we explore the influence of two RUNX2 modifiers, dexamethasone (DEX) and 1,25-dihydroxyvitamin D3 (1,25-D3), in DDR in differentiating MC3T3-E1 preosteoblasts challenged by oxidative stress. The process of differentiation was associated with reactive oxygen species (ROS) production and tert-butyl hydroperoxide (TBH) reduced the rate of differentiation. The activity of alkaline phosphatase (ALP), a marker of the process of osteoblasts differentiation, increased in a time-dependent manner and TBH further increased this activity. This may indicate that additional oxidative stress, induced by TBH, may accelerate the differentiation process. The cells displayed changes in the sensitivity to TBH in the course of differentiation. DEX increased ALP activity, but 1,25-D3 had no effect on it. These results suggest that DEX might stimulate the process of preosteoblasts differentiation. Finally, we observed a protective effect of DEX and 1,25-D3 against DNA damage induced by TBH, except the day 24 of differentiation, when DEX increased the extent of TBH-induced DNA damage. We conclude that oxidative stress is associated with osteoblasts differentiation and induce DDR, which may be modulated by RUNX2-modifiers, DEX and 1,25-D3. Full article
(This article belongs to the Section Biochemistry)
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Article
Deactivation of 6-Aminocoumarin Intramolecular Charge Transfer Excited State through Hydrogen Bonding
by Ewa Krystkowiak, Krzysztof Dobek and Andrzej Maciejewski
Int. J. Mol. Sci. 2014, 15(9), 16628-16648; https://doi.org/10.3390/ijms150916628 - 19 Sep 2014
Cited by 9 | Viewed by 6813
Abstract
This paper presents results of the spectral (absorption and emission) and photophysical study of 6-aminocoumarin (6AC) in various aprotic hydrogen-bond forming solvents. It was established that solvent polarity as well as hydrogen-bonding ability influence solute properties. The hydrogen-bonding interactions between S1-electronic [...] Read more.
This paper presents results of the spectral (absorption and emission) and photophysical study of 6-aminocoumarin (6AC) in various aprotic hydrogen-bond forming solvents. It was established that solvent polarity as well as hydrogen-bonding ability influence solute properties. The hydrogen-bonding interactions between S1-electronic excited solute and solvent molecules were found to facilitate the nonradiative deactivation processes. The energy-gap dependence on radiationless deactivation in aprotic solvents was found to be similar to that in protic solvents. Full article
(This article belongs to the Special Issue Chemical Bond and Bonding 2015)
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