Search Results (52)

Lymphoma is the most common neoplasm of lymphoid tissues in dogs. Exportin 1 (XPO1) is an important major nuclear receptor for exporting proteins and RNA species. The XPO1 upregulation can eliminate some tumor suppressor proteins (TSPs) function upon their nuclear–cytoplasmic export. The XPO1 inhibitor, KPT-335, blocks the translocation of TSPs and restores their function to induce cell cycle arrest, apoptosis, and cell proliferation. This in vitro study aimed to evaluate the XPO1 mRNA and protein expression in canine lymphoma cell lines and confirm the relevance with KPT-335. XPO1 mRNA and protein levels were quantified, and the effect of KPT-335 was assessed by a cell proliferation assay. The results indicated that XPO1 mRNA and protein were highly expressed in 17-71, CLBL-1, CLC, CLGL-90, and UL-1, and were moderately expressed in GL-1, Ema, and Nody-1. All canine lymphoma cell lines showed dose-dependent growth inhibition and decreased cell viability in response to KPT-335, with IC₅₀ concentrations ranged from 89.8–418 nM. The expression levels of XPO1 mRNA and protein were related; however, no correlation was found between those expression levels and the efficacy of KPT-335. These findings suggest that XPO1 may represent a promising target for therapeutic intervention in canine lymphoma. Full article

Oxidative stress is a key mediator of physiological dysfunction in aquatic organisms under environmental challenges, yet its comprehensive impacts on gill physiology require further clarification. This study investigated the molecular and cellular responses of Eriocheir sinensis gills to hydrogen peroxide (H₂O₂)-induced oxidative stress, integrating antioxidant defense, ion transport regulation, and stress-induced cell apoptosis and autophagy. Morphological alterations in the gill filaments were observed, characterized by septum degeneration, accumulation of haemolymph cells, and pronounced swelling. For antioxidant enzymes like catalase (CAT) and glutathione peroxidase (GPx), activities were enhanced, while superoxide dismutase (SOD) activity was reduced following 48 h of exposure. Overall, the total antioxidant capacity (T-AOC) showed a significant increase. The elevated concentrations of malondialdehyde (MDA) and H₂O₂ indicated oxidative stress. Ion transport genes displayed distinct transcription patterns: Na⁺-K⁺-2Cl⁻ co-transporter-1 (NKCC1), Na⁺/H⁺ exchanger 3 (NHE3), aquaporin 7 (AQP7), and chloride channel protein 2 (CLC2) were significantly upregulated; the α-subunit of Na⁺/K⁺-ATPase (NKAα) and carbonic anhydrase (CA) displayed an initial increase followed by decline; whereas vacuolar-type ATPase (VATP) consistently decreased, suggesting compensatory mechanisms to maintain osmotic balance. Concurrently, H₂O₂ triggered apoptosis (Bcl2, Caspase-3/8) and autophagy (beclin-1, ATG7), likely mediated by MAPK and AMPK signaling pathways. These findings reveal a coordinated yet adaptive response of crab gills to oxidative stress, providing new insights into the mechanistic basis of environmental stress tolerance in crustaceans. Full article

Background: The pathogenesis of neuropsychiatric lupus erythematosus (NPSLE) is very complex and is associated with neuroinflammation and blood–brain barrier compromise. Experimental investigations of NPSLE have classically relied on spontaneous models. Recently, TLR7 agonist-induced lupus has been shown to exhibit similar neuropsychiatric manifestations to spontaneous ones. Cinnamon is a widespread spice and natural flavoring agent. It has been proven to modulate vascular endothelial tight junctions, neuroinflammation, and autoimmunity pathways, but it has never been tested in relation to lupus. Hypothesis/Purpose: In this pilot study, we aimed to explore the disease-modifying effect of Cinnamomum cassia on NPSLE in a TLR7 agonist-induced model. Study Design: An experimental design was followed in this study. Methods: Lupus was induced in C57BL/6J female mice via the direct application of imiquimod, a TLR7 agonist (5% imiquimod cream, 1.25 mg three times weekly), to the skin. Mice were divided into five groups (n = 8 per group): a sham group (S), a sham group supplemented with cinnamon (SC), an imiquimod-treated group (L), an imiquimod-treated group supplemented with cinnamon starting from induction (LC), and an imiquimod-treated group supplemented with cinnamon beginning two weeks prior to induction (CLC). This protocol was followed for six consecutive weeks. Cinnamomum cassia powder was administered orally at 200 mg/kg, 5 days per week. Results: Behavioral alterations were significantly ameliorated in the CLC group compared to lupus mice. Neuronal shrinkage and nuclear chromatin condensation were visible in the hippocampal cornu ammonis and dentate gyrus zones of lupus mice, with an increased expression of TLR7 and NLRP3, versus significantly less neurodegeneration and TLR7 and NLRP3 expression in the CLC group. In addition, the expression of the blood–brain barrier endothelial cell tight junction proteins claudin-1, occludin, and ZO-1 was abnormally modified in lupus mice and was restored in the CLC group. Moreover, while the cell–cell border delocalization of claudin-1 was documented in cultured blood–brain barrier endothelial cells treated with the plasma of lupus mice to a punctate intracytoplasmic fluorescence pattern, only cells treated with the plasma of the CLC group exhibited a complete reversal of this redistribution of claudin-1. Finally, cinnamaldehyde seemed to interact with TLR7 at multiple sites. Conclusions:Cinnamomum cassia seems to alleviate the pathogenesis of NPSLE. Supplementation with Cinnamomum cassia could be of great interest to modulate the activity and severity of the disease. Full article

Artemisia dracunculus/(tarragon) is a perennial plant used in traditional medicine and the food industry. The plant is known to have beneficial effects on health, such as antibacterial, antifungal, antiseptic, carminative, anti-inflammatory, antipyretic, anthelmintic, etc. In this study, the compounds present in the highest concentrations in the essential oils obtained by different extraction methods from tarragon found on the Romanian market were identified by gas chromatography–mass spectrometry. The biological activity of these compounds was predicted using the computational tools ADMETlab3.0, admetSAR3.0, CLC-Pred2.0, and AntiBac-Pred. Also, the main molecular target of these compounds was predicted and the interactions with this protein were evaluated using molecular docking. The compounds identified in high concentrations in the obtained essential oils are estragole, cis-β-ocimene, trans-β-ocimene, limonene, eugenol methyl ether, eugenol acetate, eugenol, caryophyllene oxide, and α-pinene. The absorption, distribution, metabolism, excretion, and toxicity profiles of these compounds show that they are generally safe, but some of them can cause skin sensitization and respiratory toxicity and are potential inhibitors of the organic anion transporters OATP1 and OATP2. Several of these compounds exert antibacterial activity against some species of Staphylococcus, Streptococcus, and Prevotella. All compounds reveal potential cytotoxicity for several types of cancer cells. These findings may guide further experimental studies to identify medical and pharmacological applications of tarragon extracts or specific compounds that can be isolated from these extracts. Full article

Background: Chemoresistance in triple-negative breast cancer (TNBC) presents a significant clinical hurdle, limiting the efficacy of treatments like doxorubicin. This study aimed to explore the molecular changes associated with doxorubicin resistance and identify potential therapeutic targets to overcome this resistance, thereby improving treatment outcomes for TNBC patients. Methods: Doxorubicin-resistant (DoxR) TNBC models (MDA-MB-231 and BT-549) were generated by exposing cells to increasing concentrations of doxorubicin. RNA sequencing (RNA-Seq) was performed using the Illumina platform, followed by bioinformatics analysis with CLC Genomics Workbench and iDEP. Functional assays assessed proliferation, sphere formation, migration, and cell cycle changes. Protein expression and phosphorylation were confirmed via Western blotting. Pathway and network analyses were conducted using Ingenuity Pathway Analysis (IPA) and STRING, while survival analysis was performed using Kaplan–Meier Plotter database. Results: DoxR cells exhibited reduced proliferation, sphere formation, and migration, but showed enhanced tolerance to doxorubicin. Increased CHK2 and p53 phosphorylation indicated cellular dormancy as a resistance mechanism. RNA-Seq analysis revealed upregulation of cytokine signaling and stress-response pathways, while cholesterol and lipid biosynthesis were suppressed. Activation of the IL1β cytokine network was prominent in DoxR cells, and CRISPR-Cas9 screens data identified dependencies on genes involved in rRNA biogenesis and metabolism. A 27-gene signature associated with doxorubicin resistance was linked to worse clinical outcomes in a large breast cancer cohort (HR = 1.76, FDR p < 2.0 × 10⁻¹³). Conclusions: This study uncovers potential therapeutic strategies for overcoming TNBC resistance, including dormancy reversal and targeting onco-ribosomal pathways and cytokine signaling networks, to improve the efficacy of doxorubicin-based treatments. Full article

Protists inhabit marine, brackish and fresh waters. The salt barrier plays an important role in the origin of their diversity. Salinity tolerance differs among species and sometimes even among different strains of the same species, indicating local adaptation. Dinoflagellates from the Apocalathium genus are represented by at least four species, which originated via rapid and recent radiation. Water salinity was suggested as one of the key factors for this radiation. A previous study found RNA transcripts, which belong exclusively to saline strains of Apocalathium, and were absent in its freshwater strains. In the present paper, the diversity of these transcripts and their orthologs from marine and freshwater protists were analysed using bioinformatic approaches. First, it was found that these specific transcripts translated to the proteins, which are important for osmoregulation (e.g., transport of various compounds including glycine betaine, regulation of microtubule organisation, post transcriptional modifications). This supports the idea that speciation within Apocalathium resulted in the loss of osmoregulatory genes by freshwater species. Second, protein distribution was not highly species specific, because their orthologs were found in different dinoflagellates and were relatively common in other phototrophic protists, though the sequences were highly variable. Proteins from 13 orthogroups were absent or very rare in studied freshwater genomes and transcriptomes. They could play a specific role in protists salinity tolerance. Third, detailed phylogenetic analyses of betaine-like transporter and chloride transmembrane transporters, which probably are one of the key proteins associated with salinity tolerance, revealed high levels of multiple and variable copies that were not eliminated from the genome during the evolution. The expression of their genes could be important in the adaptation of dinoflagellates to salinity changes, as it was already shown for some other protists. Full article

Dent disease type 1 is a rare X-linked recessive inherited renal disorder affecting mainly young males, generally leading to end-stage renal failure and for which there is no cure. It is caused by inactivating mutations in the gene encoding ClC-5, a 2Cl⁻/H⁺ exchanger found on endosomes in the renal proximal tubule. This transporter participates in reabsorbing all filtered plasma proteins, which justifies why proteinuria is commonly observed when ClC-5 is defective. In the context of Dent disease type 1, a proximal tubule dedifferentiation was shown to be accompanied by a dysfunctional cell metabolism. However, the exact mechanisms linking such alterations to chronic kidney disease are still unclear. In this review, we gather knowledge from several Dent disease type 1 models to summarize the current hypotheses generated to understand the progression of this disorder. We also highlight some urinary biomarkers for Dent disease type 1 suggested in different studies. Full article

Chloride channels (ClCs) have received global interest due to their significant role in the regulation of ion homeostasis, fluid transport, and electrical excitability of tissues and organs in different mammals and contributing to various functions, such as neuronal signaling, muscle contraction, and regulating the electrolytes’ balance in kidneys and other organs. In order to define the chloride voltage-gated channel (CLCN) gene family in buffalo, this study used in silico analyses to examine physicochemical properties, evolutionary patterns, and genome-wide identification. We identified eight CLCN genes in buffalo. The ProtParam tool analysis identified a number of important physicochemical properties of these proteins, including hydrophilicity, thermostability, in vitro instability, and basic nature. Based on their evolutionary relationships, a phylogenetic analysis divided the eight discovered genes into three subfamilies. Furthermore, a gene structure analysis, motif patterns, and conserved domains using TBtool demonstrated the significant conservation of this gene family among selected species over the course of evolution. A comparative amino acid analysis using ClustalW revealed similarities and differences between buffalo and cattle CLCN proteins. Three duplicated gene pairs were identified, all of which were segmental duplications except for CLCN4-CLCN5, which was a tandem duplication in buffalo. For each gene pair, the Ka/Ks test ratio findings showed that none of the ratios was more than one, indicating that these proteins were likely subject to positive selection. A synteny analysis confirmed a conserved pattern of genomic blocks between buffalo and cattle. Transcriptional control in cells relies on the binding of transcription factors to specific sites in the genome. The number of transcription factor binding sites (TFBSs) was higher in cattle compared to buffalo. Five main recombination breakpoints were identified at various places in the recombination analysis. The outcomes of our study provide new knowledge about the CLCN gene family in buffalo and open the door for further research on candidate genes in vertebrates through genome-wide studies. Full article

The nine-member CLC gene family of Cl⁻ chloride-transporting membrane proteins is divided into plasma membrane-localized Cl⁻ channels and endo-/lysosomal Cl⁻/H⁺ antiporters. Accessory proteins have been identified for ClC-K and ClC-2 channels and for the lysosomal ClC-7, but not the other CLCs. Here, we identified TMEM9 Domain Family Member B (TMEM9B), a single-span type I transmembrane protein of unknown function, to strongly interact with the neuronal endosomal ClC-3 and ClC-4 transporters. Co-expression of TMEM9B with ClC-3 or ClC-4 dramatically reduced transporter activity in Xenopus oocytes and transfected HEK cells. For ClC-3, TMEM9B also induced a slow component in the kinetics of the activation time course, suggesting direct interaction. Currents mediated by ClC-7 were hardly affected by TMEM9B, and ClC-1 currents were only slightly reduced, demonstrating specific interaction with ClC-3 and ClC-4. We obtained strong evidence for direct interaction by detecting significant Förster Resonance Energy Transfer (FRET), exploiting fluorescence lifetime microscopy-based (FLIM-FRET) techniques between TMEM9B and ClC-3 and ClC-4, but hardly any FRET with ClC-1 or ClC-7. The discovery of TMEM9B as a novel interaction partner of ClC-3 and ClC-4 might have important implications for the physiological role of these transporters in neuronal endosomal homeostasis and for a better understanding of the pathological mechanisms in CLCN3- and CLCN4-related pathological conditions. Full article

The opening of the Torpedo CLC-0 chloride (Cl⁻) channel is known to be regulated by two gating mechanisms: fast gating and slow (common) gating. The structural basis underlying the fast-gating mechanism is better understood than that of the slow-gating mechanism, which is still largely a mystery. Our previous study on the intracellular proton (H⁺_i)-induced inhibition of the CLC-0 anionic current led to the conclusion that the inhibition results from the slow-gate closure (also called inactivation). The conclusion was made based on substantial evidence such as a large temperature dependence of the H⁺_i inhibition similar to that of the channel inactivation, a resistance to the H⁺_i inhibition in the inactivation-suppressed C212S mutant, and a similar voltage dependence between the current recovery from the H⁺_i inhibition and the recovery from the channel inactivation. In this work, we further examine the mechanism of the H⁺_i inhibition of wild-type CLC-0 and several mutants. We observe that an anion efflux through the pore of CLC-0 accelerates the recovery from the H⁺_i-induced inhibition, a process corresponding to the slow-gate opening. Furthermore, various inactivation-suppressed mutants exhibit different current recovery kinetics, suggesting the existence of multiple inactivated states (namely, slow-gate closed states). We speculate that protonation of the pore of CLC-0 increases the binding affinity of permeant anions in the pore, thereby generating a pore blockage of ion flow as the first step of inactivation. Subsequent complex protein conformational changes further transition the CLC-0 channel to deeper inactivated states. Full article

The eukaryotic microalga Nannochloropsis oceanica represents a promising bioresource for the production of biofuels and pharmaceuticals. Urea, a crucial nutrient for the photosynthetic N. oceanica, stimulates the accumulation of substances such as lipids, which influence growth and physiology. However, the specific mechanisms by which N. oceanica responds and adapts to urea addition remain unknown. High-throughput mRNA sequencing and differential gene expression analysis under control and urea-added conditions revealed significant metabolic changes. This involved the differential expression of 2104 genes, with 1354 being upregulated and 750 downregulated, resulting in the reprogramming of crucial pathways such as carbon and nitrogen metabolism, photosynthesis, and lipid metabolism. The results specifically showed that genes associated with photosynthesis in N. oceanica were significantly downregulated, particularly those related to light-harvesting proteins. Interestingly, urea absorption and transport may depend not only on specialized transport channels such as urease but also on alternative transport channels such as the ABC transporter family and the CLC protein family. In addition, urea caused specific changes in carbon and lipid metabolism. Genes associated with the Calvin cycle and carbon concentration mechanisms were significantly upregulated. In lipid metabolism, the expression of genes associated with lipases and polyunsaturated fatty acid synthesis was highly activated. Furthermore, the expression of several genes involved in the tricarboxylic acid cycle and folate metabolism was enhanced, making important contributions to energy supply and the synthesis and modification of genes and macromolecules. Our observations indicate that N. oceanica actively and dynamically regulates the redistribution of carbon and nitrogen after urea addition, providing references for further research on the effects of urea on N. oceanica. Full article

Galectins are a group of β-galactoside-binding proteins with several roles in immune response, cellular adhesion, and inflammation development. Current evidence suggest that these proteins could play a crucial role in many respiratory diseases such as pulmonary fibrosis, lung cancer, and respiratory infections. From this standpoint, an increasing body of evidence have recognized galectins as potential biomarkers involved in several aspects of asthma pathophysiology. Among them, galectin-3 (Gal-3), galectin-9 (Gal-9), and galectin-10 (Gal-10) are the most extensively studied in human and animal asthma models. These galectins can affect T helper 2 (Th2) and non-Th2 inflammation, mucus production, airway responsiveness, and bronchial remodeling. Nevertheless, while higher Gal-3 and Gal-9 concentrations are associated with a stronger degree of Th-2 phlogosis, Gal-10, which forms Charcot–Leyden Crystals (CLCs), correlates with sputum eosinophilic count, interleukin-5 (IL-5) production, and immunoglobulin E (IgE) secretion. Finally, several galectins have shown potential in clinical response monitoring after inhaled corticosteroids (ICS) and biologic therapies, confirming their potential role as reliable biomarkers in patients with asthma. Full article

Chloride (Cl⁻) is considered a crucial nutrient for plant growth, but it can be a challenge under saline conditions. Excessive accumulation of Cl⁻ in leaves can cause toxicity. Chloride channels (CLCs) are expressed in the inner membranes of plant cells and function as essential Cl⁻ exchangers or channels. In response to salt stress in plants, CLCs play a crucial role, and CLC proteins assist in maintaining the intracellular Cl⁻ homeostasis by sequestering Cl⁻ into vacuoles. Sodium chloride (NaCl) is the primary substance responsible for causing salt-induced phytotoxicity. However, research on plant responses to Cl⁻ stress is comparatively rare, in contrast to that emphasizing Na⁺. This review provides a comprehensive overview of the plant response and tolerance to Cl⁻ stress, specifically focusing on comparative analysis of CLC protein structures in different species. Additionally, to further gain insights into the underlying mechanisms, the study summarizes the identified CLC genes that respond to salt stress. This review provides a comprehensive overview of the response of CLCs in terrestrial plants to salt stress and their biological functions, aiming to gain further insights into the mechanisms underlying the response of CLCs in plants to salt stress. Full article

Neutrophils are innate immune cells that play a key role in pathogen clearance. They contribute to inflammatory diseases, including diabetes, by releasing pro-inflammatory cytokines, reactive oxygen species, and extracellular traps (NETs). NETs contain a DNA backbone and catalytically active myeloperoxidase (MPO), which produces hypochlorous acid (HOCl). Chlorination of the DNA nucleoside 8-chloro-deoxyguanosine has been reported as an early marker of inflammation in diabetes. In this study, we examined the reactivity of different chlorinated nucleosides, including 5-chloro-(deoxy)cytidine (5ClC, 5CldC), 8-chloro-(deoxy)adenosine (8ClA, 8CldA) and 8-chloro-(deoxy)guanosine (8ClG, 8CldG), with the INS-1E β-cell line. Exposure of INS-1E cells to 5CldC, 8CldA, 8ClA, and 8CldG decreased metabolic activity and intracellular ATP, and, together with 8ClG, induced apoptotic cell death. Exposure to 8ClA, but not the other nucleosides, resulted in sustained endoplasmic reticulum stress, activation of the unfolded protein response, and increased expression of thioredoxin-interacting protein (TXNIP) and heme oxygenase 1 (HO-1). Exposure of INS-1E cells to 5CldC also increased TXNIP and NAD(P)H dehydrogenase quinone 1 (NQO1) expression. In addition, a significant increase in the mRNA expression of NQO1 and GPx4 was seen in INS-1E cells exposed to 8ClG and 8CldA, respectively. However, a significant decrease in intracellular thiols was only observed in INS-1E cells exposed to 8ClG and 8CldG. Finally, a significant decrease in the insulin stimulation index was observed in experiments with all the chlorinated nucleosides, except for 8ClA and 8ClG. Together, these results suggest that increased formation of chlorinated nucleosides during inflammation in diabetes could influence β-cell function and may contribute to disease progression. Full article

Myotonia congenita is a hereditary muscle disease mainly characterized by muscle hyperexcitability, which leads to a sustained burst of discharges that correlates with the magnitude and duration of involuntary aftercontractions, muscle stiffness, and hypertrophy. Mutations in the chloride voltage-gated channel 1 (CLCN1) gene that encodes the skeletal muscle chloride channel (ClC-1) are responsible for this disease, which is commonly known as myotonic chloride channelopathy. The biophysical properties of the mutated channel have been explored and analyzed through in vitro approaches, providing important clues to the general function/dysfunction of the wild-type and mutated channels. After an exhaustive search for CLCN1 mutations, we report in this review more than 350 different mutations identified in the literature. We start discussing the physiological role of the ClC-1 channel in skeletal muscle functioning. Then, using the reported functional effects of the naturally occurring mutations, we describe the biophysical and structural characteristics of the ClC-1 channel to update the knowledge of the function of each of the ClC-1 helices, and finally, we attempt to point out some patterns regarding the effects of mutations in the different helices and loops of the protein. Full article