Editorial

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3 pages, 184 KiB

Open AccessEditorial

Antioxidants and Obesity

by Francesca Bonomini

Int. J. Mol. Sci. 2023, 24(16), 12832; https://doi.org/10.3390/ijms241612832 - 16 Aug 2023

Cited by 1 | Viewed by 1094

Abstract

Obesity and its global prevalence are increasingly becoming serious worldwide risks [...] Full article

(This article belongs to the Special Issue Antioxidants and Obesity)

Research

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18 pages, 4927 KiB

Open AccessArticle

Exploring the Role of a Novel Peptide from Allomyrina dichotoma Larvae in Ameliorating Lipid Metabolism in Obesity

by Sung Mun Bae, Meiqi Fan, Young-Jin Choi, Yujiao Tang, Gwanghui Jeong, Kyungjae Myung, Byung-gyu Kim and Eun-Kyung Kim

Int. J. Mol. Sci. 2020, 21(22), 8537; https://doi.org/10.3390/ijms21228537 - 12 Nov 2020

Cited by 6 | Viewed by 2046

Abstract

The aim of this study was to identify an anti-obesity peptide from Allomyrina dichotoma and investigate the lipid metabolic mechanism. Enzymatically hydrolyzed A. dichotoma larvae were further separated using tangential flow filtration and consecutive chromatographic processes. Finally, an anti-obesity peptide that showed the [...] Read more.

The aim of this study was to identify an anti-obesity peptide from Allomyrina dichotoma and investigate the lipid metabolic mechanism. Enzymatically hydrolyzed A. dichotoma larvae were further separated using tangential flow filtration and consecutive chromatographic processes. Finally, an anti-obesity peptide that showed the highest inhibitory effect on lipid accumulation was obtained, and the sequence was Glu-Ile-Ala-Gln-Asp-Phe-Lys-Thr-Asp-Leu (EIA10). EIA10 decreased lipid aggregation in vitro and significantly reduced the accumulation of body weight gain, liver weight, and adipose tissue weight in high-fat-fed mice. Compared with the control group, the levels of total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL), insulin, and homeostasis model assessment of insulin resistance (HOMA-IR) in the high-fat diet (HFD) group increased significantly, and the content of high-density lipoprotein cholesterol (HDL) in the serum decreased significantly. On the contrary, the levels of TC, TG, and insulin in the EIA10 group decreased significantly, and the HDL content increased significantly compared with the HFD group. Additionally, EIA10 dramatically decreased mRNA and protein levels of transcription factors involved in lipid adipogenesis. Taken together, our results suggest that EIA10 could be a promising agent for the treatment and prevention of obesity. Full article

(This article belongs to the Special Issue Antioxidants and Obesity)

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23 pages, 1738 KiB

Open AccessArticle

Transcriptome Analysis of Testis from HFD-Induced Obese Rats (Rattus norvigicus) Indicated Predisposition for Male Infertility

by Ahmed M. El-Shehawi, Samir El-Shazly, Mohamed Ahmed, Mohamed Alkafafy, Samy Sayed, Samy Farouk, Saqer S. Alotaibi and Mona M. Elseehy

Int. J. Mol. Sci. 2020, 21(18), 6493; https://doi.org/10.3390/ijms21186493 - 05 Sep 2020

Cited by 7 | Viewed by 3341

Abstract

Obesity is a worldwide life-threatening metabolic disorder, associated with various chronic diseases, including male infertility. Obesity was induced by high fat diet (HFD), and testis RNA was used for the transcriptome analysis using RNAseq via Illumina NovaSeq 6000 System and NovaSeq 6000 Kit. [...] Read more.

Obesity is a worldwide life-threatening metabolic disorder, associated with various chronic diseases, including male infertility. Obesity was induced by high fat diet (HFD), and testis RNA was used for the transcriptome analysis using RNAseq via Illumina NovaSeq 6000 System and NovaSeq 6000 Kit. Gene expression level was estimated as FPKM (Fragments Per Kilobase of transcript per Million mapped reads). Differential expressed genes (DEGs) were annotated against gene ontology (GO) and KEGG databases. More than 63.66 million reads per sample were performed with 100 bp cutoff and 6 Gb sequencing depth. Results of this study revealed that 267 GO terms (245 biological processes (BP), 14 cellular components (CC), eight molecular functions (MF)), and 89 KEGG pathways were significantly enriched. Moreover, total numbers of 136 genes were differentially expressed (107 upregulated, 29 downregulated) with |FC| ≥ 2 and bh adjusted <0.05. Interesting DEGs were detected, including obesity and lipid metabolism-related genes, immune response-related genes, cytochrome P450 genes, including aromatase were upregulated, whereas genes related to male fertility and fertilization, cell adhesion, and olfactory receptors were downregulated. The combined expression pattern of the DEGs in obese animals indicated an increase in cholesterol metabolism. Furthermore, high aromatase activity enhances the testosterone turnover into estradiol and lowers the testosterone/estradiol (T/E) ratio, which ultimately reduces fertility. In addition, downregulation of cadherens junction components genes leads to the pre-mature release of sperm from Sertoli cells resulting in the reduction of fertility. Moreover, the downregulation of olfactory receptor genes reduces the chemotaxis capacity of sperms in tracking the oocyte for fertilization, which reduces male fertility. Furthermore, various obesity molecular markers were detected in our transcriptome. The results of this study will enhance our understanding of the molecular network of obesity development, development of obesity novel molecular diagnosis markers, molecular bases of obesity-induced infertility, and the development of anti-obesity drugs. Full article

(This article belongs to the Special Issue Antioxidants and Obesity)

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32 pages, 1774 KiB

Open AccessArticle

Alterations in Concentration/Activity of Superoxide Dismutases in Context of Obesity and Selected Single Nucleotide Polymorphisms in Genes: SOD1, SOD2, SOD3

by Łukasz Lewandowski, Marta Kepinska and Halina Milnerowicz

Int. J. Mol. Sci. 2020, 21(14), 5069; https://doi.org/10.3390/ijms21145069 - 17 Jul 2020

Cited by 26 | Viewed by 3151

Abstract

Little is known about the contribution of each of the three superoxide dismutase isozymes (SODs) to the total SOD activity in extracellular fluids. This study was aimed to investigate the alterations in concentration/activity of (SODs) in plasma, in context of sex, obesity, exposition [...] Read more.

Little is known about the contribution of each of the three superoxide dismutase isozymes (SODs) to the total SOD activity in extracellular fluids. This study was aimed to investigate the alterations in concentration/activity of (SODs) in plasma, in context of sex, obesity, exposition to cigarette smoke, and genotypic variability of five selected single nucleotide polymorphisms (SNPs) in genes SOD1, SOD2, SOD3. Men showed higher SOD1 concentration, lower SOD3 concentration and higher total antioxidative capacity (TAC) values. Intersexual variability was observed in concentration of copper, zinc, and cadmium. The obese showed higher total oxidative capacity regardless of sex. An increase in SOD2 activity was coexistent with obesity in men, and exposition to cigarette smoke in non-obese individuals. Additionally, in state of this exposition, Cu,Zn-SOD contribution to the total SOD was lower. Interestingly, over 90% of the obese were of C/T genotype of rs4880 (SOD2). Non-obese of T/T genotype (rs4880) were of lower total SOD activity due to decrease in both Cu,Zn-SOD and Mn-SOD activities. SNP rs2234694 was associated with differences in concentration of SODs, depending on obesity status. Correlations indicate that both TAC and SODs, together, may adapt to insulin resistance and inflammation-derived oxidative stress found in obesity. This topic should be further investigated. Full article

(This article belongs to the Special Issue Antioxidants and Obesity)

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14 pages, 4099 KiB

Open AccessArticle

Tocotrienols Influence Body Weight Gain and Brain Protein Expression in Long-Term High-Fat Diet-Treated Mice

by Yugo Kato, Yoshinori Aoki and Koji Fukui

Int. J. Mol. Sci. 2020, 21(12), 4533; https://doi.org/10.3390/ijms21124533 - 25 Jun 2020

Cited by 9 | Viewed by 3369

Abstract

Obesity induces serious diseases such as diabetes and cardiovascular disease. It has been reported that obesity increases the risk of cognitive dysfunction. Cognitive dysfunction is a characteristic symptom of Alzheimer’s and Parkinson’s diseases. However, the detailed mechanisms of obesity-induced cognitive dysfunction have not [...] Read more.

Obesity induces serious diseases such as diabetes and cardiovascular disease. It has been reported that obesity increases the risk of cognitive dysfunction. Cognitive dysfunction is a characteristic symptom of Alzheimer’s and Parkinson’s diseases. However, the detailed mechanisms of obesity-induced cognitive dysfunction have not yet been elucidated. The onset and progression of obesity-induced severe secondary diseases such as diabetes, cardiovascular events, and hypertension are deeply connected to oxidative stress. We hypothesized that obesity induces cognitive dysfunction via acceleration of reactive oxygen species (ROS) production. Vitamin E, which is a lipophilic vitamin, has strong antioxidative effects and consists of two groups: tocopherols and tocotrienols. Recently, it has been demonstrated that tocotrienols have strong neuroprotective and anti-obesity effects. In this study, we fed mice a high-fat diet (HFD) from 9 to 14 months of age and assessed the effect of tocotrienols treatment on body weight, brain oxidation levels, and cognitive function. The results revealed that treatment with tocotrienols inhibited body weight gain; further, tocotrienols reached the brain and attenuated oxidation in HFD-treated mice. These results indicate that tocotrienols have anti-obesity effects and inhibit obesity-induced brain oxidation. Full article

(This article belongs to the Special Issue Antioxidants and Obesity)

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17 pages, 2274 KiB

Open AccessArticle

Effects of a Flavonoid-Rich Extract from Citrus sinensis Juice on a Diet-Induced Obese Zebrafish

by Giuseppe Montalbano, Manuela Mania, Maria Cristina Guerrera, Rosaria Laurà, Francesco Abbate, Maria Levanti, Alessandro Maugeri, Antonino Germanà and Michele Navarra

Int. J. Mol. Sci. 2019, 20(20), 5116; https://doi.org/10.3390/ijms20205116 - 15 Oct 2019

Cited by 34 | Viewed by 4391

Abstract

Background: Obesity is a pathological condition that has reached epidemic proportions; hence, it is necessary to find novel strategies aimed at fighting this disease. The present study was designed to evaluate the effect of a flavonoid-rich extract of orange (Citrus sinensis) [...] Read more.

Background: Obesity is a pathological condition that has reached epidemic proportions; hence, it is necessary to find novel strategies aimed at fighting this disease. The present study was designed to evaluate the effect of a flavonoid-rich extract of orange (Citrus sinensis) juice (OJe) in diet-induced obese zebrafish. Methods: Adult zebrafish were divided into four diet groups: (i) normally fed (NF); (ii) overfed (OF); (iii) NF supplemented with OJe (5 mL/L in fish water; NF + OJe); and (iv) OF supplemented with OJe (OF + OJe). Each week, body weight (BW) and body mass index (BMI) were measured, and, at the end of the fifth week, euthanized zebrafish were processed for both microscopic evaluations and qPCR analyses. Results: In OF zebrafish, OJe significantly decreased both BW and BMI values and lowered the visceral adipose tissue, while it had little effect in the NF group. Moreover, it significantly reduced adipocyte cell size in both NF and OF groups in both visceral and subcutaneous adipose tissues, as well as their number in OF fish. Finally, OJe modulated some obesity-related genes, such as leptin A, ghrelin, orexin, pro-opiomelanocortin (POMC), and neuropeptide Y (NPY), in both gut and brain. Conclusion: This study adds new insights into the anti-obesity properties of orange juice and its flavonoids, suggesting their role as weight management agents through a lipolytic action linked to a restoration of metabolism-regulating gene expression. Full article

(This article belongs to the Special Issue Antioxidants and Obesity)

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Review

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17 pages, 525 KiB

Open AccessReview

The Role of the Nrf2 Signaling in Obesity and Insulin Resistance

by Shiri Li, Natsuki Eguchi, Hien Lau and Hirohito Ichii

Int. J. Mol. Sci. 2020, 21(18), 6973; https://doi.org/10.3390/ijms21186973 - 22 Sep 2020

Cited by 60 | Viewed by 7194

Abstract

Obesity, a metabolic disorder characterized by excessive accumulation of adipose tissue, has globally become an increasingly prevalent disease. Extensive studies have been conducted to elucidate the underlying mechanism of the development of obesity. In particular, the close association of inflammation and oxidative stress [...] Read more.

Obesity, a metabolic disorder characterized by excessive accumulation of adipose tissue, has globally become an increasingly prevalent disease. Extensive studies have been conducted to elucidate the underlying mechanism of the development of obesity. In particular, the close association of inflammation and oxidative stress with obesity has become increasingly evident. Obesity has been shown to exhibit augmented levels of circulating proinflammatory cytokines, which have been associated with the activation of pathways linked with inflammation-induced insulin resistance, a major pathological component of obesity and several other metabolic disorders. Oxidative stress, in addition to its role in stimulating adipose differentiation, which directly triggers obesity, is considered to feed into this pathway, further aggravating insulin resistance. Nuclear factor E2 related factor 2 (Nrf2) is a basic leucine zipper transcription factor that is activated in response to inflammation and oxidative stress, and responds by increasing antioxidant transcription levels. Therefore, Nrf2 has emerged as a critical new target for combating insulin resistance and subsequently, obesity. However, the effects of Nrf2 on insulin resistance and obesity are controversial. This review focuses on the current state of research on the interplay of inflammation and oxidative stress in obesity, the role of the Nrf2 pathway in obesity and insulin resistance, and the potential use of Nrf2 activators for the treatment of insulin resistance. Full article

(This article belongs to the Special Issue Antioxidants and Obesity)

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23 pages, 1054 KiB

Open AccessReview

Clinical Role of Extraoral Bitter Taste Receptors

by Joanna Jeruzal-Świątecka, Wojciech Fendler and Wioletta Pietruszewska

Int. J. Mol. Sci. 2020, 21(14), 5156; https://doi.org/10.3390/ijms21145156 - 21 Jul 2020

Cited by 43 | Viewed by 9610

Abstract

Humans can recognise five basic tastes: sweet, sour, salty, bitter and umami. Sour and salty substances are linked to ion channels, while sweet, bitter and umami flavours are transmitted through receptors linked to the G protein (G protein-coupled receptors; GPCRs). There are two [...] Read more.

Humans can recognise five basic tastes: sweet, sour, salty, bitter and umami. Sour and salty substances are linked to ion channels, while sweet, bitter and umami flavours are transmitted through receptors linked to the G protein (G protein-coupled receptors; GPCRs). There are two main types of GPCRs that transmit information about sweet, umami and bitter tastes—the Tas1r and TAS2R families. There are about 25 functional TAS2R genes coding bitter taste receptor proteins. They are found not only in the mouth and throat, but also in the intestines, brain, bladder and lower and upper respiratory tract. The determination of their purpose in these locations has become an inspiration for much research. Their presence has also been confirmed in breast cancer cells, ovarian cancer cells and neuroblastoma, revealing a promising new oncological marker. Polymorphisms of TAS2R38 have been proven to have an influence on the course of chronic rhinosinusitis and upper airway defensive mechanisms. TAS2R receptors mediate the bronchodilatory effect in human airway smooth muscle, which may lead to the creation of another medicine group used in asthma or chronic obstructive pulmonary disease. The discovery that functionally compromised TAS2R receptors negatively impact glucose homeostasis has produced a new area of diabetes research. In this article, we would like to focus on what facts have been already established in the matter of extraoral TAS2R receptors in humans. Full article

(This article belongs to the Special Issue Antioxidants and Obesity)

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19 pages, 674 KiB

Open AccessReview

Therapeutic Effect of Seaweed Derived Xanthophyl Carotenoid on Obesity Management; Overview of the Last Decade

by Oyindamola Vivian Ojulari, Seul Gi Lee and Ju-Ock Nam

Int. J. Mol. Sci. 2020, 21(7), 2502; https://doi.org/10.3390/ijms21072502 - 03 Apr 2020

Cited by 20 | Viewed by 4812

Abstract

Present-day lifestyles associated with high calorie-fat intake and accumulation, as well as energy imbalance, have led to the development of obesity and its comorbidities, which have emerged as some of the major health issues globally. To combat the disease, many studies have reported [...] Read more.

Present-day lifestyles associated with high calorie-fat intake and accumulation, as well as energy imbalance, have led to the development of obesity and its comorbidities, which have emerged as some of the major health issues globally. To combat the disease, many studies have reported the anti-obesity effects of natural compounds in foods, with some advantages over chemical treatments. Carotenoids, such as xanthophyll derived from seaweeds, have attracted the attention of researchers due to their notable biological activities, which are associated mainly with their antioxidant properties. Their involvement in oxidative stress modulation, the regulation of major transcription factors and enzymes, and their antagonistic effects on various obesity parameters have been examined in both in vitro and in vivo studies. The present review is a collation of published research over the last decade on the antioxidant properties of seaweed xanthophyll carotenoids, with a focus on fucoxanthin and astaxanthin and their mechanisms of action in obesity prevention and treatment. Full article

(This article belongs to the Special Issue Antioxidants and Obesity)

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30 pages, 334 KiB

Open AccessReview

Plant Extracts and Reactive Oxygen Species as Two Counteracting Agents with Anti- and Pro-Obesity Properties

by Hanna Zielinska-Blizniewska, Przemyslaw Sitarek, Anna Merecz-Sadowska, Katarzyna Malinowska, Karolina Zajdel, Marta Jablonska, Tomasz Sliwinski and Radoslaw Zajdel

Int. J. Mol. Sci. 2019, 20(18), 4556; https://doi.org/10.3390/ijms20184556 - 14 Sep 2019

Cited by 37 | Viewed by 5220

Abstract

Obesity is a complex disease of great public health significance worldwide: It entails several complications including diabetes mellitus type 2, cardiovascular dysfunction and hypertension, and its prevalence is increasing around the world. The pathogenesis of obesity is closely related to reactive oxygen species. [...] Read more.

Obesity is a complex disease of great public health significance worldwide: It entails several complications including diabetes mellitus type 2, cardiovascular dysfunction and hypertension, and its prevalence is increasing around the world. The pathogenesis of obesity is closely related to reactive oxygen species. The role of reactive oxygen species as regulatory factors in mitochondrial activity in obese subjects, molecules taking part in inflammation processes linked to excessive size and number of adipocytes, and as agents governing the energy balance in hypothalamus neurons has been examined. Phytotherapy is the traditional form of treating health problems using plant-derived medications. Some plant extracts are known to act as anti-obesity agents and have been screened in in vitro models based on the inhibition of lipid accumulation in 3T3-L1 cells and activity of pancreatic lipase methods and in in vivo high-fat diet-induced obesity rat/mouse models and human models. Plant products may be a good natural alternative for weight management and a source of numerous biologically-active chemicals, including antioxidant polyphenols that can counteract the oxidative stress associated with obesity. This review presents polyphenols as natural complementary therapy, and a good nutritional strategy, for treating obesity without serious side effects. Full article

(This article belongs to the Special Issue Antioxidants and Obesity)

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