Myricetin protects against diet-induced obesity and ameliorates oxidative stress in C57BL/6 mice

Histological and biochemical effects of an ethanolic extract of Myrtus communis leaf on the pancreases of rats fed high fat diets

We investigated the effects of an ethanolic extract of Myrtus communis subsp. communis (MC) leaves on the pancreases of rats fed with a high fat diet (HFD). Wistar albino rats were fed either with standard lab chow (Control group) or with a 45% fat diet (HFD and HFD+MC groups) for 4 months, with the MC extract (100 mg/kg) being administered by orogastric gavage to rats in the HFD+MC group during the last month. Blood and pancreas samples were collected from all experimental groups at the end of the study. Insulin and leptin levels, and the lipid profile, were analyzed in the blood serum. Pancreatic injury was assessed histologically. Insulin, nuclear factor kappa beta (NF-κB), and alpha-smooth muscle actin (α-SMA) were assessed using immunohistochemistry. Apoptosis was assessed using terminal deoxynucleotidyl transferase dUTP nick end-labeling (TUNEL) immunohistochemistry. In addition, oxidant/antioxidant activity was analyzed by biochemical methods. Increased body weight, serum insulin and leptin levels, blood glucose level and pancreatic tissue malondialdehyde (MDA), 8-hydroxy-2'-deoxyguanosine (8-OHdG) levels, myeloperoxidase (MPO) activity and decreased tissue glutathione (GSH) level were observed in the HFD group compared to the Control group, in addition to dyslipidemia. An increased histopathological damage score, pancreatic islet area, insulin, TUNEL, NF-κB and α-SMA immunoreactivity were seen in animals from the HFD group compared to the Control group. However, such pathological changes were reduced in the HFD+MC group. Our data indicate further investigation of MC extract as a therapeutic adjuvant for HFD-induced pancreatic injury, acting via anti-inflammatory and antioxidant mechanisms, is worth carrying out.

Lipid lowering and anti-ageing effects of edible flowers of Viola x wittrockiana Gams in a Caenorhabditis elegans obese model

Life expectancy has increased considerably in the last decades, clearing the way for preventive medicine. The ingestion of healthy foods or ingredients to improve health is gaining attention and edible flowers entail a promising source of bioactive compounds. The aim of this work was to study the anti-ageing and anti-obesity properties of an extract obtained from an edible flower Viola x wittrockiana though in vitro and in vivo methodologies with Caenorhabditis elegans as a model. The capacity to inhibit the enzymes α-glucosidase and lipase as well as to prevent advance glycation end-product (AGE) formation was tested in vitro. Caenorhabditis elegans was used as an obesity in vivo model to assess the effects of the extract on fat accumulation, development, progeny and health span. Viola flowers showed lower IC50 values in the α-glucosidase assay than the reference drug acarbose and exerted a higher inhibition of AGE formation than the reference substance aminoguanidine; the extract also showed pancreatic lipase inhibiting properties. Moreover, the extract lowered fat storage of C. elegans in a dose-dependent manner, up to 90.37% at the highest tested dose, and improved health span biomarkers such as lipofuscin accumulation and progeny availability. Our results demonstrate, for the first time, the anti-obesogenic and anti-ageing activity of Viola x wittrockiana flowers and their potential use as functional foods and nutraceuticals.

Phenylboronic Ester-Bridged Chitosan/Myricetin Nanomicelle for Penetrating the Endothelial Barrier and Regulating Macrophage Polarization and Inflammation against Ischemic Diseases

The brain and liver are more susceptible to ischemia and reperfusion (IR) injury (IRI), which triggers the reactive oxygen species (ROS) burst and inflammatory cascade and results in severe neuronal damage or hepatic injury. Moreover, the damaged endothelial barrier contributes to proinflammatory activity and limits the delivery of therapeutic agents such as some macromolecules and nanomedicine despite the integrity being disrupted after IRI. Herein, we constructed a phenylboronic-decorated chitosan-based nanoplatform to deliver myricetin, a multifunctional polyphenol molecule for the treatment of cerebral and hepatic ischemia. The chitosan-based nanostructures are widely studied cationic carriers for endothelium penetration such as the blood-brain barrier (BBB) and sinusoidal endothelial barrier (SEB). The phenylboronic ester was chosen as the ROS-responsive bridging segment for conjugation and selective release of myricetin molecules, which meanwhile scavenged the overexpressed ROS in the inflammatory environment. The released myricetin molecules fulfill a variety of roles including antioxidation through multiple phenolic hydroxyl groups, inhibition of the inflammatory cascade by regulation of the macrophage polarization from M1 to M2, and endothelial injury repairment. Taken together, our present study provides valuable insight into the development of efficient antioxidant and anti-inflammatory platforms for potential application against ischemic disease.

The activity comparison of six dietary flavonoids identifies that luteolin inhibits 3T3-L1 adipocyte differentiation through reducing ROS generation

Mitochondrial reactive oxygen species (ROS)generation plays an essential role in the process of adipocyte differentiation and is involved in the development of obesity and associated metabolic diseases. Various dietary flavonoids possess the substantial anti-adipogenic activity. However, it is unclear whether these flavonoids inhibit adipocyte differentiation by reducing ROS generation. In this study, the effects of six common dietary flavonoids on adipocyte differentiation were assessed in 3T3-L1 cells. The flavonoids with the same backbone of 5,7-dihydroxylflavone, including flavones apigenin, chrysin, luteolin and flavonols kaempferol, myricetin, quercetin, dose-dependently inhibited 3T3-L1 adipocyte differentiation, suggesting an associated hierarchy of inhibitory capability: luteolin > quercetin > myricetin > apigenin/kaempferol > chrysin. Meanwhile, six flavonoids were found to inhibit adipogenic gene expression and the early stage of adipocyte differentiation. Among the tested flavonoids, luteolin significantly reduced both intracellular and mitochondrial ROS generation during adipocyte differentiation. Further, luteolin treatment depressed the elevation of H₂O₂ concentration in the early stage of 3T3-L1 differentiation and reversed the facilitated effects of exogenous H₂O₂ on 3T3-L1 adipocyte differentiation and ROS generation. Altogether, the activity comparison of six dietary flavonoids identifies that luteolin inhibits 3T3-L1 adipocyte differentiation through reducing ROS generation, elucidating a new mechanism underlying the anti-adipogenic actions of flavonoids.

GPX2 Gene Affects Feed Efficiency of Pigs by Inhibiting Fat Deposition and Promoting Muscle Development

GPX2 has been recognized as a potential candidate gene for feed efficiency in pigs. This article aimed to elucidate polymorphism of GPX2 associated with feed efficiency and its related molecular mechanism. In this study, seven single nucleotide polymorphisms (SNP) of GPX2 were found among 383 Duroc pigs. In addition, seven SNPs and ALGA0043483 (PorcineSNP60 BeadChip data in 600 Duroc pigs), which are near the GPX2 gene, were identified in one haplotypes block. Furthermore, associated studies showed that the genotype of GPX2 has significant association with weaning weight and 100 kg BF in Duroc pigs. In addition, the AG had no effect when the backfat became thinner, and the FCR and RFI traits had a tendency to decrease in the G3 + TT combination genotype, accompanied by an increase of GPX2 expression in backfat and muscle tissues. At the cellular level, the adipocyte proliferation and ability of adipogenic differentiation were reduced, and the lipid degradation increased in 3T3-L1 when there was overexpression of GPX2. In contrast, overexpression of the GPX2 gene can promote the muscle cell proliferation and myogenic differentiation in C2C12 cells. In other words, GPX2 has the effect of reducing fat deposition and promoting muscle development, and it is a candidate gene for backfat and feed efficiency.

A novel anti-obesity mechanism for liraglutide by improving adipose tissue leptin resistance in high-fat diet-fed obese mice

Liraglutide has been approved for the treatment of obesity in the past few years. Both oxidative stress and leptin resistance are the critical drivers of obesity. The present study investigated the mechanism of liraglutide protection against obesity by ameliorating leptin resistance and oxidative stress. Male C57BL/6J mice were fed a high-fat diet (HFD) and subcutaneously injected with 200 μg/kg/d liraglutide for 20 weeks. Body weight, fat mass, serum levels of leptin, insulin, and superoxide dismutase (SOD) activities were measured. In addition, glucose and insulin tolerance tests were performed. The expressions of leptin, its signaling genes, and antioxidant enzymes were detected using RT-qPCR and western blot methods in liver and white adipose tissue (WAT) of mice. The results depicted that liraglutide treatment significantly slowed weight gain of body, reduced the fat mass, ameliorated glucose and lipid metabolism, and hepatic steatosis in HFD-fed obese mice. Further study demonstrated that liraglutide treatment resulted in decreased serum levels and the transcript levels of leptin as well as leptin signaling inhibitory regulators. However, it increased leptin receptor expression and the phosphorylation of signal transducer and activator of transcription 3 (p-STAT3) in WAT (p < 0.05). In addition, the antioxidant enzyme expression was elevated in both liver and WAT of liraglutide-treated mice (p < 0.05). In conclusion, liraglutide conspicuously prevented obesity and ameliorated glucose and lipid metabolism in obese mice through a novel mechanism that improves peripheral leptin resistance in WAT and enhance the antioxidant enzyme expression in both liver and WAT.

Potential of Natural Honey in Controlling Obesity and its Related Complications

Honey has a long history of therapeutic properties for multiple diseases, including inflammation and oxidative stress. This review aimed to provide a better understanding and renewed interest in the potential role of honey in obesity control, obesity-related diseases treatment and weight management, with specific reference to its components and the effect of honey overall. There is compelling evidence that honey possesses the desired properties for this purpose, as seen in the in vitro, in silico, in vivo and clinical analyses discussed in this review. This review also highlights the components potentially responsible for the health benefits of honey. Honey and its components reduce blood sugar levels, improve insulin sensitivity and lipid metabolism by reducing triglycerides, and reduce total cholesterol and LDL levels while increasing HDL levels that prevent excessive weight gain and reduce the risk of obesity and its complications. Further controlled studies are necessary to validate the role of honey in the management of obesity, both as a preventive and as a therapeutic agent.

Methanolic fruit extract of Myrica nagi protects the hypothalamus and attenuates inflammation associated with gold thioglucose- and high-fat diet-induced obesity via various adipokines

BACKGROUND

Myrica nagi is popular in unani and ayurveda. Chemical constituents like myricetin isolated from its fruit has been shown to exert beneficial effects against cardiovascular disease, cancer, inflammatory conditions, and metabolic disorders.

OBJECTIVES

This study aimed to elucidate the anti-obesity effect of the methanolic extract of M. nagi (MEMN) using in vivo animal models of obesity induced by gold thioglucose or a high-fat diet.

MATERIALS AND METHODS

The obese mice were treated or untreated with MEMN for 8 weeks. Thereafter, feed intake, Lee index, and body mass index (BMI); biochemical parameters such as lipid profile, liver enzymes and specific biomarkers of obesity, including insulin, leptin, adiponectin, free fatty acids (FFA), monocyte chemoattractant protein (MCP)-1, and resistin, were recorded. The weight and histopathology of organs and fat tissue were examined to validate the effectiveness of the extract.

RESULTS

MEMN administration at various doses significantly reduced the induced weight gain, feed intake, BMI, and Lee index. Adipose tissue decreased as the MEMN dose increased. MEMN attenuated liver enzyme activity, decreased lipid, leptin, MCP-1, resistin, and FFA levels, and increased adiponectin levels. It also increased protection of liver cells and decreased accumulation of mesenteric fat.

CONCLUSIONS

MEMN supplementation decreased weight and improved obesity serum/plasma lipid biomarker, insulin, leptin, adiponectin, MCP-1, and resistin levels. The weight-reducing activity of MEMN may be mediated by decreased gastrointestinal fat absorption and modulation of inflammation associated signaling pathways, leading to reduced adipose inflammation associated with energy expenditure.

Anti-obesity and Anti-diabetic Effect of Ursolic Acid against Streptozotocin/High Fat Induced Obese in Diabetic Rats

Obesity is occurring due to continue taken high fat diet; this is the fast-growing problem reaching epidemic proportion globally. Ursolic acid altered the abnormal glucose metabolism in diabetic rats. In this experimental protocol, we examine ursolic acid (UA) anti-obesity effect against streptozotocin (STZ) and high-fat diet-induced obesity in rats. Orally administered the ursolic acid (2.5, 5 and 10 mg/kg) dose to the hyperglycemic rats for 8 weeks and estimated the blood glucose level at different time intervals. Biochemical, hepatic, lipid, renal and antioxidant parameters were estimated. Traf-4, Mapk-8, Traf-6 and genes such as Ins-1, ngn-3 and Pdx-1 mRNA expression were estimated using qRT-PCR to scrutinize the molecular mechanism in MAPK downstream JNK cascade and insulin pathway signalling pathways. Ursolic acid significantly (p<0.001) down-regulated the blood glucose level at dose dependent manner. Its also reduced the plasma insulin level, non-essential fatty acid and increased the level of adiponectin as compared to obese control group rats. Ursolic acid treated group rats reduced the level of total cholesterol and triglycerides. Ursolic-acid-treated rats have been shown to decrease oxidative stress in pancreatic tissue by restoring the free radical effect of scavenging, suppress the Traf-6, Mapk-8 and Traf-4 mRNA expression, enhance the expression of Pdx-1, Ins-1 and Ngn-3 and ensure the regeneration of pancreas β cells and therefore pancreas insulin. The current result suggested the anti-obese effect of ursolic acid against high fat diet (HFD) induced obese rats via alteration of insulin and JNK signaling pathway.

The crucial role of oxidative stress in non-alcoholic fatty liver disease-induced male reproductive toxicity: the ameliorative effects of Iranian indigenous probiotics

Several studies have focused on the high potential effects of probiotics on the reproductive system. However, there is a paucity of information regarding the ameliorative intracellular roles of indigenous Iranian yogurt-extracted/cultured probiotics on animals' reproductive health suffering from obesity and/or fatty liver disease, such as non-alcoholic fatty liver disease (NAFLD). For this purpose, simultaneously with the consumption of D-fructose (200 g/1000 mL water, induction of NAFLD model), all pubertal animals were also gavaged every day for 63 consecutive days with extracted probiotics, including 1 × 109 CFU/mL of Lactobacillus acidophilus (LA), Bifidobacterium spp. (BIF), Bacillus coagulans (BC), Lactobacillus rhamnosus (LR), and a mixture form (LA + BIF + BC + LR). At the end of the ninth week, the indices of epididymal sperm, and oxidative stress, as well as histopathological changes, were assessed. The results show that NAFLD could induce robust oxidative stress, highlighted as considerable increments in ROS level, TBARS content, total oxidized protein levels, along with severe decrements in reduced glutathione reservoirs, total antioxidant capacity in the hepatic and testicular tissues, as well as testicular and hepatic histopathological alterations. Moreover, a significant decrease in the percentage of sperm progressive motility, sperm count, and membrane integrity along with an increment in the percentage of sperm abnormality was detected in NAFLD animals. The observed adverse effects were significantly reversed upon probiotics treatment, especially in the group challenged with a mixture of all probiotics. Taken together, these findings indicate that the indigenous yogurt-isolated/cultured probiotics had a high potential antioxidant activity and the ameliorative effect against reprotoxicity and blood biochemical alterations induced by the NAFLD model. Highlights: 1. Reproductive indices could be reversely affected by xenobiotics and diseases. 2. NAFLD and cholestasis considerably affect the reproductive system in both genders. 3. NAFLD induced hepatic and testicular oxidative stress (OS). 4. NAFLD induced histopathological alterations and spermatotoxicity through OS. 5. The adverse effects were significantly reversed upon exposure to probiotics.

Beneficial Effects of Laurel (Laurus nobilis L.) and Myrtle (Myrtus communis L.) Extract on Rat Health

Polyphenols of Laurel and Myrtle exhibit structural diversity, which affects bioavailability, metabolism, and bioactivity. The gut microbiota plays a key role in modulating the production, bioavailability and, thus the biological activities of phenolic metabolites, particularly after the intake of food containing high-molecular-weight polyphenols. The aim of this study was to investigate whether the polyphenolic components of Laurel and Myrtle aqueous extract have beneficial effects on rat health. The growth of lactic acid bacteria (LAB), β-glucuronidase, β-glucosidase, β-galactosidase activity, pH value, body weight change and food efficacy ratio after intragastric treatment of rats with Laurel and Myrtle extract at doses of 50 and 100 mg/kg for two weeks were investigated. The endogenous populations of colonic probiotic bacteria (Lactobacilli and Bifidobacteria) were counted on selective media. According to the obtained data, Laurel extract in the applied dose of 50 and 100 and Myrtle extract (100 mg/kg) positively affects the rats health by increasing the number of colonies of Lactobacilli and Bifidobacteria compared to the control group, causes changes in glycolytic enzymatic activity and minor change in antioxidative tissue activity. In addition, high doses of Laurel increase food efficiency ratio, while Myrtle has the same effect at a lower dose.

Phytochemistry profile of rosella and jambolan extracts and the therapeutic effects on obesity

Hibiscus sabdariffa extract (HSE) and Syzygium cumini extract (SCE) have been used in traditional medicine due to their hypoglycemic, antidiabetic, anti-obesity and antioxidant activities. The aim of this study was...

Ameliorative Effect of Myricetin on Nonalcoholic Fatty Liver Disease in ob/ob Mice

Obesity, insulin resistance, and oxidative stress are important risk factors for nonalcoholic fatty liver disease (NAFLD). This study aimed at determining the beneficial effects of myricetin against NAFLD in ob/ob mice. C57BL/6-Lep^ob/ob mice (n = 21) were fed an AIN-93G diet (ob/ob control group) or diet containing 0.04% (low myricetin; LMTN group) or 0.08% (high myricetin; HMTN group) myricetin, and lean heterozygous littermates (lean control group, n = 7) were fed AIN-93G diet for 10 weeks. HMTN consumption significantly lowered serum glucose levels and homeostasis model assessment for insulin resistance values in ob/ob mice. In addition to reducing serum triglyceride (TG) and cholesterol levels, HMTN significantly decreased total hepatic lipid and TG levels partly through downregulation of carbohydrate response element-binding protein and sterol regulatory element-binding protein 1c expression. The reduction in the levels of hepatic thiobarbituric acid reactive substances by HMTN likely resulted from the elevation of nuclear factor erythroid-2-related factor 2 expression. Tumor necrosis factor-α and monocyte chemoattractant protein 1 expressions were reduced by LMTN and HMTN, and HMTN also decreased interleukin-6 expression. These results suggest that myricetin has beneficial effects against NAFLD by regulating the expression of transcription factors of hepatic lipid metabolism, the antioxidant system, and pro-inflammatory cytokines.

Gastroprotective Effect of Myricetin on Ethanol-Induced Acute Gastric Injury in Rats

The flavonoid myricetin is abundant in vegetables and has various bioactive properties, including anti-inflammatory and antioxidative activities. In the present study, we explored the effects of myricetin on alcohol-induced gastric ulcer in a rat model. To induce gastric ulcer, absolute ethanol (5 mL/kg body weight) was orally administrated to each rat. The positive control and myricetin-treated groups were given oral doses of omeprazole (20 mg/kg) or myricetin (12 mg/kg), respectively, 1 hour prior to the administration of absolute alcohol. We found that pretreatment with myricetin significantly decreased alcohol-induced gastric ulcer, hemorrhage, hyperemia, and epithelial cell loss in the gastric mucosa. Myricetin pretreatment reduced the level of malondialdehyde (MDA) and increased that of total glutathione (GSSG/GSH) and superoxide dismutase (SOD) in gastric tissues. In addition, it elevated the expression levels of cyclooxygenase-1 (COX-1) and prostaglandin E₂ (PGE₂) and decreased the phosphorylation of nuclear factor kappa B (NF-κB). Together, these results indicate that myricetin effectively inhibits ethanol-induced acute gastric injury by preventing oxidative damage, stimulating PGE₂ production, and inhibiting NF-κB activation. We suggest that myricetin may be an alternative treatment for gastric injury caused by alcohol intake.

Myricetin 3-O-β-D-Galactopyranoside Exhibits Potential Anti-Osteoporotic Properties in Human Bone Marrow-Derived Mesenchymal Stromal Cells via Stimulation of Osteoblastogenesis and Suppression of Adipogenesis

Natural bioactive substances are promising lead compounds with beneficial effects on various health problems including osteoporosis. In this context, the goal of this study was to investigate the effect of myricetin 3-O-β-D-galactopyranoside (M3G), a glycoside of a known bioactive phytochemical myricetin, on bone formation via osteogenic differentiation of human bone marrow-derived mesenchymal stromal cells (hBM-MSCs). The hBM-MSCs were induced to differentiate into osteoblasts and adipocytes in the presence or absence of M3G and the differentiation markers were analyzed. Osteoblastogenesis-induced cells treated with M3G exhibited stimulated differentiation markers: cell proliferation, alkaline phosphatase (ALP) activity, and extracellular mineralization. In terms of intracellular signaling behind the stimulatory effect of M3G, the expression of RUNX2 and osteopontin transcription factors were upregulated. It has been shown that M3G treatment increased the activation of Wnt and BMP as a suggested mechanism of action for its effect. On the other hand, M3G treatment during adipogenesis-inducement of hBM-MSCs hindered the adipogenic differentiation shown as decreased lipid accumulation and expression of PPARγ, SREBP1c, and C/EBPα, adipogenic transcription factors. In conclusion, M3G treatment stimulated osteoblast differentiation and inhibited adipocyte differentiation in induced hBM-MSCs. Osteoblast formation was stimulated via Wnt/BMP and adipogenesis was inhibited via the PPARγ pathway. This study provided necessary data for further studies to utilize the therapeutic potential of M3G against osteoporosis via regulation of bone marrow stromal cell differentiation.

Myricetin: A comprehensive review on its biological potentials

Myricetin is a critical nutritive component of diet providing immunological protection and beneficial for maintaining good health. It is found in fruits, vegetables, tea, and wine. The families Myricaceae, Polygonaceae, Primulaceae, Pinaceae, and Anacardiaceae are the richest sources of myricetin. Different researchers explored the therapeutic potential of this valuable constituent such as anticancer, antidiabetic, antiobesity, cardiovascular protection, osteoporosis protection, anti-inflammatory, and hepatoprotective. In addition to these, the compound has been tested for cancer and diabetic mellitus during clinical trials. Health benefits of myricetin are related to its impact on different cell processes, such as apoptosis, glycolysis, cell cycle, energy balance, lipid level, serum protein concentrations, and osteoclastogenesis. This review explored the potential health benefits of myricetin with a specific emphasis on its mechanism of action, considering the most updated and novel findings in the field.

Natural Aldose Reductase Inhibitor: A Potential Therapeutic Agent for Non-alcoholic Fatty Liver Disease

Aldose reductase (AR) has been reported to be involved in the development of nonalcoholic fatty liver disease (NAFLD). Hepatic AR is induced under hyperglycemia condition and converts excess glucose to lipogenic fructose, which contributes in part to the accumulation of fat in the liver cells of diabetes rodents. In addition, the hyperglycemia-induced AR or nutrition-induced AR causes suppression of the transcriptional activity of peroxisome proliferator-activated receptor (PPAR) α and reduced lipolysis in the liver, which also contribute to the development of NAFLD. Moreover, AR induction in non-alcoholic steatohepatitis (NASH) may aggravate oxidative stress and the expression of inflammatory cytokines in the liver. Here, we summarize the knowledge on AR inhibitors of plant origin and review the effect of some plant-derived AR inhibitors on NAFLD/NASH in rodents. Natural AR inhibitors may improve NAFLD at least in part through attenuating oxidative stress and inflammatory cytokine expression. Some of the natural AR inhibitors have been reported to attenuate hepatic steatosis through the regulation of PPARα-mediated fatty acid oxidation. In this review, we propose that the natural AR inhibitors are potential therapeutic agents for NAFLD.

Myricetin: A review of the most recent research

Myricetin(MYR) is a flavonoid compound widely found in many natural plants including bayberry. So far, MYR has been proven to have multiple biological functions and it is a natural compound with promising research and development prospects. This review comprehensively retrieved and collected the latest pharmacological abstracts on MYR, and discussed the potential molecular mechanisms of its effects. The results of our review indicated that MYR has a therapeutic effect on many diseases, including tumors of different types, inflammatory diseases, atherosclerosis, thrombosis, cerebral ischemia, diabetes, Alzheimer's disease and pathogenic microbial infections. Furthermore, it regulates the expression of Hippo, MAPK, GSK-3β, PI3K/AKT/mTOR, STAT3, TLR, IκB/NF-κB, Nrf2/HO-1, ACE, eNOS / NO, AChE and BrdU/NeuN. MYR also enhances the immunomodulatory functions, suppresses cytokine storms, improves cardiac dysfunction, possesses an antiviral potential, can be used as an adjuvant treatment against cancer, cardiovascular injury and nervous system diseases, and it may be a potential drug against COVID-19 and other viral infections. Generally, this article provides a theoretical basis for the clinical application of MYR and a reference for its further use.

Flavonoids as antiobesity agents: A review

Obesity is a global health problem that affects all age groups in both developing and developed countries. In recent years, the prevalence of overweight and obesity has reached pandemic levels, resulting in a dramatic increase in the incidence of various comorbidities, such as cardiovascular diseases, type 2 diabetes, and cancer, consequently leading to massive health and socioeconomic burdens. Together with lifestyle changes, antiobesity pharmacotherapy is gaining momentum as an adjunctive treatment. However, the available pharmacological approaches have limited use owing to either significant adverse effects or low efficacy. Over the years, natural products have been an important source of lead compounds for drug discovery. Among these, flavonoids are associated with important biological effects and health-promoting activities. In this review, we discuss the modulatory effects of flavonoids on obesity and their potential mechanisms of action. The literature strongly suggests that most common flavonoids demonstrate a pronounced effect on obesity as shown by their ability to lower body weight, fat mass, and plasma triglycerides/cholesterol, both in in vitro and in vivo models. The impact of flavonoids on obesity can be observed through different mechanisms: reducing food intake and fat absorption, increasing energy expenditure, modulating lipid metabolism, or regulating gut microbiota profile. A better understanding of the known antiobesity mechanisms of flavonoids will enable their potential use to treat this medical condition. Therefore, this review focuses on the putative biological mechanisms through which flavonoids may prevent or treat obesity and highlights new perspectives on future pharmacological use.

Modeling Diet-Induced Metabolic Syndrome in Rodents

Standardized animal models represent one of the most valuable tools available to understand the mechanism underlying the metabolic syndrome (MetS) and to seek for new therapeutic strategies. However, there is considerable variability in the studies conducted with this essential purpose. This review presents an updated discussion of the most recent studies using diverse experimental conditions to induce MetS in rodents with unbalanced diets, discusses the key findings in metabolic outcomes, and critically evaluates what we have been learned from them and how to advance in the field. The study includes scientific reports sourced from the Web of Science and PubMed databases, published between January 2013 and June 2020, which used hypercaloric diets to induce metabolic disorders, and address the impact of the diet on metabolic parameters. The collected data are used as support to discuss variables such as sex, species, and age of the animals, the most favorable type of diet, and the ideal diet length to generate metabolic changes. The experimental characteristics propose herein improve the performance of a preclinical model that resembles the human MetS and will guide researchers to investigate new therapeutic alternatives with confidence and higher translational validity.

The Protective Effects of Myricetin against Cardiovascular Disease

Cardiovascular disease (CVD) is the leading cause of death globally, except Africa, and poses a severe health burden worldwide. Both in vitro and in vivo studies have demonstrated the protective effects of myricetin for preventing CVD. For this review, we have assessed the literature from 2009 to 2019 at home and abroad to uncover the protective roles of myricetin for preventing CVD. Myricetin exhibits cardioprotective, anti-hypertensive, anti-atherosclerotic, anti-hyperglycemic, and anti-hyperlipidemic effects. In addition, myricetin may alleviate some of the complications caused by adult-onset diabetes. The combined functions of myricetin allow for the prevention of CVD. This review describes the possible therapeutic benefits of myricetin, along with its potential mechanisms of action, to support the clinical use of the myricetin for the prevention of CVD.

Protective Effects of Myricetin on Benzo[a]pyrene-Induced 8-Hydroxy-2'-Deoxyguanosine and BPDE-DNA Adduct

Benzo[a]pyrene (B[a]P), a group 1 carcinogen, induces mutagenic DNA adducts. Myricetin is present in many natural foods with diverse biological activities, such as anti-oxidative and anti-cancer activities. The aim of this study was to investigate the protective effects of myricetin against B[a]P-induced toxicity. Treatment of B[a]P induced cytotoxicity on HepG2 cells, whereas co-treatment of myricetin with B[a]P reduced the formation of the B[a]P-7,8-dihydrodiol-9,10-epoxide (BPDE)-DNA adduct, which recovered cell viability. Furthermore, we found a protective effect of myricetin against B[a]P-induced genotoxicity in rats, via myricetin-induced inhibition of 8-hydroxy-2′-deoxyguanosine (8-OHdG) and BPDE-DNA adduct formation in the liver, kidney, colon, and stomach tissue. This inhibition was more prominent in the liver than in other tissues. Correspondingly, myricetin regulated the phase I and II enzymes that inhibit B[a]P metabolism and B[a]P metabolites conjugated with DNA by reducing and inducing CYP1A1 and glutathione S-transferase (GST) expression, respectively. Taken together, this showed that myricetin attenuated B[a]P-induced genotoxicity via regulation of phase I and II enzymes. Our results suggest that myricetin is anti-genotoxic, and prevents oxidative DNA damage and BPDE-DNA adduct formation via regulation of phase I and II enzymes.

The effect of hydroalcoholic Berberis integerrima fruits extract on the lipid profile, antioxidant parameters and liver and kidney function tests in patients with nonalcoholic fatty liver disease

Background

Non-alcoholic fatty liver disease (NAFLD) is one of the hepatic disorders which is characterized by increasing fat deposits in the liver. This disorder may lead to elevation the activity of liver enzymes and is associated with obesity, dyslipidemia, hypertension, and type II diabetes. The aim of present study was to investigate the effect of Berberis integerrima extract on NAFLD patients compare to placebo.

Methods

The present clinical trial was performed on 42 NAFLD patients who were randomly divided into two groups. The case group received a capsule (750 mg) containing hydro-alcoholic extract of Berberis integerrima extract every 12 h for 2 months, while the control (placebo) group received a capsule containing cellulose. Baseline characteristics, biochemical factors, antioxidant parameter, functional liver and renal test were evaluated before and after the treatment.

Results

Comparison rate of different parameters in case group before and after treatment demonstrated that BMI, cholesterol, triglyceride, LDL-C, fasting blood glucose, liver enzymes and renal parameters such as aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase were significantly decreased while HDL-C, glutathione peroxidase enzyme, and total antioxidant capacity were significantly elevated. The comparison of the mean parameters difference in two groups indicated that cholesterol, triglyceride, LDL-C, fasting blood glucose, liver enzymes and renal factors were significantly decreased, however HDL-C, glutathione peroxidase enzyme, and total antioxidant capacity were significantly increased in case group compared to control group.

Conclusion

The study findings revealed that the Berberis integerrima extract could reduce biochemical factors of blood, except HDL-C and increases total antioxidant capacity and glutathione peroxidase enzyme. Therefore, hydro-alcoholic extract of Berberis integerrima may be used as a great supplementary medicine in treating NAFLD.

Safflower Yellow and Its Main Component HSYA Alleviate Diet-Induced Obesity in Mice: Possible Involvement of the Increased Antioxidant Enzymes in Liver and Adipose Tissue

Purpose

Oxidative stress plays an important role in the pathogenesis of obesity and its associated disorders. Safflower yellow (SY) and hydroxysafflor yellow A (HSYA), the natural compounds isolated from Carthamus tinctorius L., has been found to possess antioxidative and anti-obesity properties. The purpose of the present study is to investigate whether SY and its main component HSYA alleviate obesity by the antioxidant effects.

Methods

Diet-induced obese (DIO) mice were treated with 200 mg/kg/d SY or HSYA for 10 weeks. Body weight, fat mass, serum biochemical parameters and superoxide dismutase (SOD) activities were measured. Glucose and insulin tolerance tests were performed. The expression of antioxidant enzymes in liver and adipose tissue were measured. In vitro, H₂O₂-induced oxidative stress HepG2 cells and 3T3-L1 adipocytes were treated with SY and HSYA to investigate the direct effects of SY and HSYA on the expression of antioxidant enzymes.

Results

SY and HSYA significantly decreased the body weight gain of DIO mice, and decreased fat mass to 57.8% and 61.6% of the control mice, respectively (P < 0.05). The parameters of glucose metabolism and liver function were improved after SY and HSYA treatment. The hepatic SOD activities and the mRNA levels of antioxidant enzymes in liver and adipose tissue of SY and HSYA treated mice were increased (P < 0.05). Meanwhile, the administration of SY and HSYA on the H₂O₂-induced oxidative stress HepG2 cells and adipocytes also increased the expression of the antioxidant factor and antioxidant enzymes to 1.2~3.3 folds of the control cells (P < 0.05).

Conclusion

SY and its main component HSYA could significantly decrease the fat mass, and improve glucose metabolism and liver function in diet-induced obese mice. The beneficial effects of SY and HSYA on obesity and metabolism may be associated with the increased expression of antioxidant enzymes in liver and adipose tissue.

Targeting obesity with plant-derived pancreatic lipase inhibitors: A comprehensive review

The prevalence of obesity is alarmingly increasing in the last few decades and leading to many serious public health concerns worldwide. The dysregulated lipid homeostasis due to various genetic, environmental and lifestyle factors is considered one of the critical putative pathways mediating obesity. Nonetheless, the scientific advancements unleashing the molecular dynamics of lipid metabolism have provided deeper insights on the emerging roles of lipid hydrolysing enzymes, including pancreatic lipase. It is hypothesized that inhibiting pancreatic lipase would prevent the breakdown of triglyceride and delays the absorption of fatty acids into the systemic circulation and adipocytes. Whilst, orlistat is the only conventional pancreatic lipase enzyme inhibitor available in clinics, identifying the safe clinical alternatives from plants to inhibit pancreatic lipase has been considered a significant advancement. Consequently, plants which have shown significant potential to combat obesity are now revisited for its abilities to inhibit pancreatic lipase. In this regard, our review surveyed the potential of medicinal plants and its phytoconstituents to inhibit pancreatic lipase and to elicit anti-obesity effects. Thus, the review collate and critically appraise the potential of medicinal plants and phyto-molecules inhibiting pancreatic lipase enzyme and consequently modulating triglyceride absorption in gut, and discuss its implications in the development of novel therapeutic strategies to combat obesity.

Luteolin reduces fat storage inCaenorhabditis elegansby promoting the central serotonin pathway

Luteolin promotes central serotonin signaling to induce fat loss.

Mulberry Fruit Extract Ameliorates Nonalcoholic Fatty Liver Disease (NAFLD) through Inhibition of Mitochondrial Oxidative Stress in Rats

Mulberry is known to have pharmacological effects against cholesterol, obesity, and dyslipidemia. Many studies have revealed that mulberry leaf possesses hepatoprotective properties against nonalcoholic fatty liver disease (NAFLD); however, mulberry fruit is less studied in this context. Therefore, this study aimed to investigate the preventive effects of mulberry fruit against high fat diet- (HFD-) induced NAFLD. To evaluate the effects of mulberry fruit on NAFLD, two doses of mulberry fruit ethanol extracts [MB, 100, and 200 mg/kg BW (body weight)] were given to HFD-fed rats for 10 weeks. MB dramatically prevented liver damage as shown by biochemical analysis of the liver injury markers, alanine transaminase, and aspartate transaminase. MB treatment significantly inhibited the increased levels of total cholesterol, triacylglycerol, and low-density lipoprotein-cholesterol but restored the level of high-density lipoprotein-cholesterol in HFD-fed rats. Notably, histological analysis of liver tissues demonstrated that MB substantially ameliorated lipid accumulation. Expression of cholesterol-regulating genes was also suppressed by MB treatment. For its underlying mechanisms, MB suppressed hepatic reactive oxygen species (ROS) overproduction and mitochondrial oxidative stress in HFD-fed rats. MB potentially protects liver tissue against NAFLD by inhibition of mitochondrial oxidative stress, suggesting its possible use as a therapeutic agent for treatment of NAFLD.

Myricetin Exerts Anti-Obesity Effects through Upregulation of SIRT3 in Adipose Tissue

Myricetin is a biologically active natural polyphenol with beneficial effects on metabolic health. This study aimed to examine the effects of myricetin on the expression levels of genes involved in lipolysis and mitochondrial respiration in adipocytes and the anti-obesity potential of myricetin. The results indicated that myricetin reduced triglyceride (TG) content and increased mitochondrial content and oxygen consumption rate (OCR) in adipocytes in vitro. To determine anti-obesity effect of myricetin, C57BL6/J mice were fed a high-fat diet (HFD) for eight weeks and then treated with myricetin (10 mg/kg) for 2 weeks. The in vivo treatment of myricetin reduced body weight by 11%. Furthermore, it improved the glucose tolerance, and increased fatty acid consumption of HFD-fed mice. Myricetin treatment increased Sirt3 expression and reduced the acetylation of mitochondrial proteins in adipose tissue. Finally, the knockdown of Sirt3 in adipocytes reduced the myricetin-induced increase in mitochondrial oxygen consumption rate by about 27% compared to controls. Our results indicated that myricetin exerted anti-obesity effects through the upregulation of Sirt3 expression and mitochondrial metabolism in adipose tissue.

Phenolic acid and flavonoid-rich fraction of Sasa quelpaertensis Nakai leaves prevent alcohol induced fatty liver through AMPK activation

ETHNOPHARMACOLOGICAL RELEVANCE

Sasa quelpaertensis Nakai is an edible dwarf bamboo cultivated mainly in Jeju Island, South Korea and its leaf displays various health-promoting properties including antioxidant scavenging.

AIM OF THE STUDY

In this study, we aimed at elucidating its hepatoprotective effect against alcohol-induced fatty liver.

METHODS

In in vitro study, we evaluated the cytotoxicity and hepatoprotective effect of different solvent fractions (aqua, butanol, chloroform, ethyl acetate and hexane) of 80% EtOH extract of S. quelpaertensis Nakai leaf. In vivo experiment performed using binge alcohol consumption model.

RESULTS

Although all five fractions (0-1000 µg/mL) were non-cytotoxic to HepG2 cells, only ethyl acetate fraction (SQEA), rich in phenolic acids such as p-coumaric acid and flavonoids particularly myristin, showed hepatoprotective effect against EtOH (400 mM) in HepG2 cells. Furthermore, SQEA significantly decreased the ethanol induced cell death and enhanced the cell proliferation. In in vivo experiment using binge consumption model (5 g of EtOH/kg body weight in every 12 h for 3 times), SQEA treatment (10, 50 and 100 mg/kg) markedly reduced the alcohol induced histopathological changes and serum EtOH content, and reversed the reduction of glutathione level in ethanol challenged livers. Further, it suppressed the expression of cytochrome P450 2E1 (CYP2E1). In particular, SQEA activated AMP activated protein kinase (AMPK) pathway, and decreased the expression of tumor necrosis factor receptor-1 (TNFR1), which attenuated lipogenesis via decreased expression of fatty acid synthase (FAS). Inhibited lipogenesis due to SQEA treatment directed towards decreased perilipin-2 expression. These results indicate that SQEA has hypolipidemic effect which is mediated by decreased oxidative stress, increased fatty acid oxidation response and decreased lipogenesis.

CONCLUSION

Our results suggest the possibility of developing SQEA as a natural hepatoprotective agent potent in attenuating alcohol-induced fatty liver.

Procyanidin B2 ameliorates free fatty acids-induced hepatic steatosis through regulating TFEB-mediated lysosomal pathway and redox state

Procyanidin B2, a naturally occurring phenolic compound, has been reported to exert multiple beneficial functions. However, the effect of procyanidin B2 on free fatty acids (FFAs)-induced hepatic steatosis remains obscure. The present study is therefore aimed to elucidate the protective effect of procyanidin B2 against hepatic steatosis and its underlying mechanism. Herein, we reported that procyanidin B2 attenuated FFAs-induced lipid accumulation and its associated oxidative stress by scavenging excessive ROS and superoxide anion radicals, blocking loss of mitochondrial membrane potential, restoring glutathione content, and increasing activity of antioxidant enzymes (GPx, SOD and CAT) in hepatocytes. Procyanidin B2 mechanistically promoted lipid degradation via modulation of transcription factor EB (TFEB), a master regulator of lysosomal pathway. Molecular docking analysis indicated a possible ligand-binding position of procyanidin B2 with TFEB. In addition, administration of procyanidin B2 resulted in a significant reduction of hepatic fat accumulation in high-fat diet (HFD)-induced obese mice, and also ameliorated HFD-induced metabolic abnormalities, including hyperlipidemia and hyperglycemia. It was confirmed that procyanidin B2 prevented HFD-induced hepatic fat accumulation through down-regulating lipogenesis-related gene expressions (PPARγ, C/EBPα and SREBP-1c), inhibiting pro-inflammatory cytokines production (IL-6 and TNF-α) and increasing antioxidant enzymes activity (GPx, SOD and CAT). Moreover, hepatic fatty acids analysis indicated that procyanidin B2 caused a significant increase in the levels of palmitic acid, oleic acid and linoleic acid. Intriguingly, procyanidin B2 restored the decreased nuclear TFEB expression in HFD-induced liver steatosis and up-regulated its target genes involved in lysosomal pathway (Lamp1, Mcoln, Uvrag), which suggested a previously unrecognized mechanism of procyanidin B2 on ameliorating HFD-induced hepatic steatosis. Taken together, our results demonstrated that procyanidin B2 attenuated FFAs-induced hepatic steatosis through regulating TFEB-mediated lysosomal pathway and redox state, which had important implications that modulation of TFEB might be a potential therapeutic strategy for hepatic steatosis and procyanidin B2 could represent a promising novel agent in the prevention and treatment of non-alcoholic fatty liver disease (NAFLD).

Regulation of autophagy by tea polyphenols in diabetic cardiomyopathy

OBJECTIVE

To investigate the effect of tea polyphenols on cardiac function in rats with diabetic cardiomyopathy, and the mechanism by which tea polyphenols regulate autophagy in diabetic cardiomyopathy.

METHODS

Sixty Sprague-Dawley (SD) rats were randomly divided into six groups: a normal control group (NC), an obesity group (OB), a diabetic cardiomyopathy group (DCM), a tea polyphenol group (TP), an obesity tea polyphenol treatment group (OB-TP), and a diabetic cardiomyopathy tea polyphenol treatment group (DCM-TP). After successful modeling, serum glucose, cholesterol, and triglyceride levels were determined; cardiac structure and function were inspected by ultrasonic cardiography; myocardial pathology was examined by staining with hematoxylin-eosin; transmission electron microscopy was used to observe the morphology and quantity of autophagosomes; and expression levels of autophagy-related proteins LC3-II, SQSTM1/p62, and Beclin-1 were determined by Western blotting.

RESULTS

Compared to the NC group, the OB group had normal blood glucose and a high level of blood lipids; both blood glucose and lipids were increased in the DCM group; ultrasonic cardiograms showed that the fraction shortening was reduced in the DCM group. However, these were improved significantly in the DCM-TP group. Hematoxylin-eosin staining showed disordered cardiomyocytes and hypertrophy in the DCM group; however, no differences were found among the remaining groups. Transmission electron microscopy revealed that the numbers of autophagosomes in the DCM and OB-TP groups were obviously increased compared to the NC and OB groups; the number of autophagosomes in the DCM-TP group was reduced. Western blotting showed that the expression of LC3-II/I and Beclin-1 increased obviously, whereas the expression of SQSTM1/p62 was decreased in the DCM and OB-TP groups (P<0.05).

CONCLUSIONS

Tea polyphenols had an effect on diabetic cardiomyopathy in rat cardiac function and may alter the levels of autophagy to improve glucose and lipid metabolism in diabetes.

Antiobesity and Antioxidant Potentials of Selected Palestinian Medicinal Plants

We evaluated the antioxidant and porcine pancreatic lipase inhibition (PPLI) activities of 90 plants extracts. The antioxidant activity was measured using the free-radical scavenging capacity (DPPH) and reducing power (RP) assays. The pancreatic lipase inhibition assay was used to determine the PPLI activity of plant extracts. Among the 90 plant extracts examined, 41.0 % crude extracts showed antilipase activity of more than 50%. The most active plants by means of IC₅₀ value were Camellia sinensis (0.5 mg/ml), Ceratonia siliqua (leaves) (0.8 mg/mL), Curcuma longa (0.8 mg/mL), Sarcopoterium spinosum (1.2 mg/mL), and Mentha spicata (1.2 mg/mL). The antioxidant activity of plant extracts using the DPPH and RP assays reveals comparable results. The most active antioxidant extracts using both assays were the leaves and fruit epicarp of Rhus coriaria, areal parts of Sarcopoterium spinosum, and leaves of Ceratonia siliqua. Our results suggest natural resources that possess strong antioxidant and pancreatic lipase inhibitory activities with potential applications in the treatment and prevention of obesity and overweight. The extracts of Camellia sinensis, Ceratonia siliqua, Curcuma longa, Sarcopoterium spinosum, and Mentha spicata were proved to have a great potential as antioxidants and antiobesity agents.

Dietary flavonoids as a potential intervention to improve redox balance in obesity and related co-morbidities: a review

Obesity represents one of major health problems strongly linked to other co-morbidities, such as type 2 diabetes, CVD, gastrointestinal disorders and cognitive impairment. In this context, nutritional stress, such as an excess of fat intake, promotes a systemic oxidative stress, characterised by hyperproduction of reactive oxygen species, leading to cellular alterations that include impaired energy metabolism, altered cell signalling and cell cycle control, impaired cell transport mechanisms and overall dysfunctional biological activity. Flavonoids, dietary components of plant foods, are endowed with a wide spectrum of biological activities, including antioxidant activity, and have been proposed to reduce the risk of major chronic diseases. The present review intends to highlight and critically discuss the current scientific evidence on the possible effects of flavonoids in counteracting obesity and related co-morbidities (i.e. type 2 diabetes mellitus, CVD, gastrointestinal disorders and cognitive impairment) through a decrease in oxidative stress and related inflammatory conditions.

Myricetin, a potent natural agent for treatment of diabetic skin damage by modulating TIMP/MMPs balance and oxidative stress

Foot ulceration is a major cause of morbidity in patients with diabetes, and abnormal peripheral neuropathy often results in hospitalization. Up-regulation of matrix metalloproteinases and down-regulation of tissue inhibitor of metalloproteinase 1 are noted to be distinctive biological functions of diabetic dermal fibroblasts. The aim of this study was to evaluate the biological effects of modified retinoids on diabetic fibroblasts. Myricetin, a natural compound, balances the TIMP1/MMP ratio and oxidative stress in diabetic fibroblasts. Our results indicate that myricetin significantly ameliorates the effects of diabetes on dermal fibroblasts. In addition, we found that the oxidative stress imbalance induced by a high glucose concentration plays an important role in the changes to dermal fibroblasts that occur in diabetes. Our findings support the hypothesis that myricetin has the potential to repair faulty skin function arising from diabetes.

Effects of honey fromMimosa quadrivalvisL. (malícia) produced by theMelipona subnitidaD. (jandaíra) stingless bee on dyslipidaemic rats

The supplementation with malícia honey alters the lipid metabolism, antioxidant status and intestinal health parameters of rats with diet-induced dyslipidaemia.

Lactobacillus rhamnosus PB01 (DSM 14870) supplementation affects markers of sperm kinematic parameters in a diet-induced obesity mice model

Probiotics have been proposed as alternatives to pharmacological products in several medical conditions including the modulation of obesity, which is frequently associated with poor semen quality. However, effects of probiotics on male fertility have been less investigated. This study assessed the effect of Lactobacillus rhamnosus PB01 (DSM-14870) on sperm kinematic parameters in Normal-weight (NW) and diet-induced obese (DIO) models. NW and DIO C57BL/6NTac mice were divided into two subgroups with or without a single daily dose (1x109CFU) of L. rhamnosus for four weeks. Sperm motility and kinematics together with blood lipid profiles and reproductive hormone levels were assessed using the sperm class analyzer system. Probiotic supplementation increased serum testosterone, LH and FSH levels in both NW and DIO groups resulting in significantly (P<0.05) higher velocity (VSL, VCL and VAP) and percentages of progressively motile sperm and significantly lower percentages of immotile sperm. Other kinematic parameters (Lin, STR, ALH and BCF) were also increased in both probiotic supplemented DIO and NW groups at the 10% level of significance. Probiotic supplemented DIO mice demonstrated significantly higher percentages of progressively motile sperm versus DIO controls. This study demonstrated the potential of L. rhamnosus PB01 as a regulatory agent with positive effects on weight loss and reproductive-hormones, significantly improving sperm motility and kinematic parameters in male DIO models.

Antioxidant and antidiabetic properties of tartary buckwheat rice flavonoids after in vitro digestion

Oxidative stress and diabetes have a tendency to alter protein, lipid, and DNA moieties. One of the strategic methods used to reduce diabetes-associated oxidative stress is to inhibit the carbohydrate-digesting enzymes, thereby decreasing gastrointestinal glucose production. Plant-derived natural antioxidant molecules are considered a therapeutic tool in the treatment of oxidative stress and diabetes. The objective of this study was to identify tartary buckwheat rice flavonoids and evaluate the effect of in vitro digestion on their antioxidant and antidiabetic properties. High performance liquid chromatography (HPLC) analysis indicated the presence of rutin as a major component and quercitrin as a minor component of both digested and non-digested flavonoids. Both extracts showed a significant antioxidant capacity, but digested flavonoids showed reduced activity compared to non-digested. There were some decreases of the antioxidant activities (2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid) diammonium salt (ABTS), 2,2-diphenyl-1-picrylhydrazy (DPPH) radical, and ferric reducing antioxidant power (FRAP)) of digested tartary buckwheat rice flavonoids compared with non-digested. Flavonoids from both groups significantly inhibited reactive oxygen species (ROS) production and α-glucosidase activity. Both digested and non-digested flavonoids markedly increased glucose consumption and glycogen content in HepG2 cells. Tartary buckwheat rice flavonoids showed appreciable antioxidant and antidiabetic properties, even after digestion. Tartary buckwheat rice appears to be a promising functional food with potent antioxidant and antidiabetic properties.

Detection of oxidative stress biomarkers in myricetin treated red blood cells

Effect of myricetin on RBC membrane enzymes (Na⁺, K⁺-ATPase and Ca²⁺-ATPase) and Na⁺, H⁺exchanger.