Resveratrol and Quercetin Administration Improves Antioxidant DEFENSES and reduces Fatty Liver in Metabolic Syndrome Rats

A promising therapy for fatty liver disease: PCSK9 inhibitors

BACKGROUND

Fatty liver disease (FLD) poses a significant global health concern worldwide, with its classification into nonalcoholic fatty liver disease (NAFLD) and alcoholic fatty liver disease (AFLD) contingent upon the presence or absence of chronic and excessive alcohol consumption. The absence of specific therapeutic interventions tailored to FLD at various stages of the disease renders its treatment exceptionally arduous. Despite the fact that FLD and hyperlipidemia are intimately associated, there is still debate over how lipid-lowering medications affect FLD. Proprotein Convertase Subtilisin/ Kexin type 9 (PCSK9) is a serine protease predominantly synthesized in the liver, which has a crucial impact on cholesterol homeostasis. Research has confirmed that PCSK9 inhibitors have prominent lipid-lowering properties and substantial clinical effectiveness, thereby justifying the need for additional exploration of their potential role in FLD.

PURPOSE

Through a comprehensive literature search, this review is to identify the relationship and related mechanisms between PCSK9, lipid metabolism and FLD. Additionally, it will assess the pharmacological mechanism and applicability of PCSK9 inhibitors (including naturally occurring PCSK9 inhibitors, such as conventional herbal medicines) for the treatment of FLD and serve as a guide for updating the treatment protocol for such conditions.

METHODS

A comprehensive literature search was conducted using several electronic databases, including Pubmed, Medline, Embase, CNKI, Wanfang database and ClinicalTrials.gov, from the inception of the database to 30 Jan 2024. Key words used in the literature search were "fatty liver", "hepatic steatosis", "PCSK9", "traditional Chinese medicine", "herb medicine", "botanical medicine", "clinical trial", "vivo", "vitro", linked with AND/OR. Most of the included studies were within five years.

RESULTS

PCSK9 participates in the regulation of circulating lipids via both LDLR dependent and independent pathways, and there is a potential association with de novo lipogenesis. Major clinical studies have demonstrated a positive correlation between circulating PCSK9 levels and the severity of NAFLD, with elevated levels of circulating PCSK9 observed in individuals exposed to chronic alcohol. Numerous studies have demonstrated the potential of PCSK9 inhibitors to ameliorate non-alcoholic steatohepatitis (NASH), potentially completely alleviate liver steatosis, and diminish liver impairment. In animal experiments, PCSK9 inhibitors have exhibited efficacy in alleviating alcoholic induced liver lipid accumulation and hepatitis. Traditional Chinese medicine such as berberine, curcumin, resveratrol, piceatannol, sauchinone, lupin, quercetin, salidroside, ginkgolide, tanshinone, lunasin, Capsella bursa-pastoris, gypenosides, and Morus alba leaves are the main natural PCS9 inhibitors. Excitingly, by inhibiting transcription, reducing secretion, direct targeting and other pathways, traditional Chinese medicine exert inhibitory effects on PCSK9, thereby exerting potential FLD therapeutic effects.

CONCLUSION

PCSK9 plays an important role in the development of FLD, and PCSK9 inhibitors have demonstrated beneficial effects on lipid regulation and FLD in both preclinical and clinical studies. In addition, some traditional Chinese medicines have improved the disease progression of FLD by inhibiting PCSK9 and anti-inflammatory and antioxidant effects. Consequently, the inhibition of PCSK9 appears to be a promising therapeutic strategy for FLD.

E-Stilbenes: General Chemical and Biological Aspects, Potential Pharmacological Activity Based on the Nrf2 Pathway

Stilbenes are phytoalexins, and their biosynthesis can occur through a natural route (shikimate precursor) or an alternative route (in microorganism cultures). The latter is a metabolic engineering strategy to enhance production due to stilbenes recognized pharmacological and medicinal potential. It is believed that in the human body, these potential activities can be modulated by the regulation of the nuclear factor erythroid derived 2 (Nrf2), which increases the expression of antioxidant enzymes. Given this, our review aims to critically analyze evidence regarding E-stilbenes in human metabolism and the Nrf2 activation pathway, with an emphasis on inflammatory and oxidative stress aspects related to the pathophysiology of chronic and metabolic diseases. In this comprehensive literature review, it can be observed that despite the broad number of stilbenes, those most frequently explored in clinical trials and preclinical studies (in vitro and in vivo) were resveratrol, piceatannol, pterostilbene, polydatin, stilbestrol, and pinosylvin. In some cases, depending on the dose/concentration and chemical nature of the stilbene, it was possible to identify activation of the Nrf2 pathway. Furthermore, the use of some experimental models presented a challenge in comparing results. In view of the above, it can be suggested that E-stilbenes have a relationship with the Nrf2 pathway, whether directly or indirectly, through different biological pathways, and in different diseases or conditions that are mainly related to inflammation and oxidative stress.

Neuroprotective potential of Marsilea quadrifolia Linn against monosodium glutamate-induced excitotoxicity in rats

Background: Excitotoxicity is a condition in which neurons are damaged/injured by the over-activation of glutamate receptors. Excitotoxins play a crucial part in the progression of several neurological diseases. Marsilea quadrifolia Linn (M. quadrifolia) is a very popular aquatic medicinal plant that has been utilised for a variety of therapeutic benefits since ancient times. Its chemical composition is diverse and includes phenolic compounds, tannins, saponins, flavonoids, steroids, terpenoids, alkaloids, carbohydrates and several others that possess antioxidant properties. Objective: The objective of the present study was to investigate the neuroprotective potential of M. quadrifolia against monosodium glutamate (MSG)-induced excitotoxicity in rats. Methods: A high-performance thin-layer chromatography (HPTLC) analysis of chloroform extract of M. quadrifolia (CEMQ) was conducted to identify the major constituents. Further, the in silico docking analysis was carried out on selected ligands. To confirm CEMQ's neuroprotective effects, the locomotor activity, non-spatial memory, and learning were assessed. Results and discussion: The present study confirmed that CMEQ contains quercetin and its derivatives in large. The in-silico findings indicated that quercetin has a better binding affinity (-7.9 kcal/mol) towards the protein target 5EWJ. Animals treated with MSG had 1) a greater reduction in the locomotor score and impairment in memory and learning 2) a greater increase in the blood levels of calcium and sodium and 3) neuronal disorganization, along with cerebral edema and neuronal degeneration in the brain tissues as compared to normal control animals. The changes were however, significantly improved in animals which received standard drug memantine (20 mg/kg) and CEMQ (200 and 400 mg/kg) as compared to the negative control. It is plausible that the changes seen with CEMQ may be attributed to the N-methyl-D-aspartate (NMDA) antagonistic properties. Conclusion: Overall, this study indicated that M. quadrifolia ameliorated MSG-induced neurotoxicity. Future investigations are required to explore the neuroprotective mechanism of M. quadrifolia and its active constituents, which will provide exciting insights in the therapeutic management of neurological disorders.

Screening of the phytochemical constituents of Teucrium polium extract and evaluation of their prophylactic role against the oxidative damage and cytotoxicity of Aflatoxin B1 in rats

Aflatoxin B1 (AFB1) is common carcinogen causing acute and chronic hepatocyte injuries. This study aimed to determine the bioactive components of Teucrium polium methanolic extract (TPE) and to evaluate their protective role against AFB1-induced oxidative damage, cytotoxicity, and genotoxicity in rats. Six groups of male albino rats were treated orally for 4 weeks including the control group, the ِAFB1-treated group (80 μg/kg b.w.), the groups treated with low (LD) or high (HD) dose TPE (50 or 100 mg/kg b.w.), and the groups treated with AFB1 plus TEP (LD) or TPE (HD). Blood and serum samples were collected for different assays. The GC-MS identified 34 compounds, the major compounds were pinene, germacrene D, α-cadinol, α-thujene, epi-bicyclosesquiphellandrene, and limonene. Animals that received AFB1 showed significant changes in all indicators of oxidative stress, biochemistry, cytokines, MNPCEs, comet tail formation in bone marrow, mRNA expression of inflammatory-related genes, Nrf2, and iNOS beside histological changes in the liver. TPE at the two doses tested showed insignificant changes in all tested parameters. The extract could normalize most of these parameters and the hepatic structure in AFB1-treated animals in a dose-dependent fashion. therefore, we concluded that TPE supplementation is effective for protection against AFB1 in endemic areas.

Resveratrol Promotes Gluconeogenesis by Inhibiting SESN2-mTORC2-AKT Pathway in Calf Hepatocytes

BACKGROUND

The glucose requirement of dairy cows is mainly met by increasing the rate of hepatic gluconeogenesis. However, due to negative energy balance, the liver of periparturient cows is under oxidative stress induced by lipid over-mobilization, and hepatic gluconeogenesis is reduced. Studies have demonstrated that resveratrol, which is widely known for its antioxidant properties, can alter hepatic gluconeogenesis. However, it is not clear whether resveratrol could regulate hepatic gluconeogenesis by its antioxidant properties.

OBJECTIVES

This study aims to investigate the precise effect of resveratrol in hepatic gluconeogenesis, the role of resveratrol on hydrogen peroxide (H2O2)-induced oxidative stress in hepatocytes and the potential mechanism using primary hepatocytes.

METHODS

Primary hepatocytes were isolated from 5 healthy Holstein calves (1 d old, 30 to 40 kg, fasted) and treated with different concentrations of resveratrol (0, 5, 10, 25, or 50 μM) combined with or without H2O2 (0, 100, or 200 μM) induction for 12 h.

RESULTS

Resveratrol enhanced the expression of gluconeogenic genes of calf hepatocytes in a dose-dependent manner (P < 0.05). Conversely, H2O2 suppressed the expression of gluconeogenic genes and induced oxidative stress (P < 0.05), which was improved by resveratrol in calf hepatocytes (P < 0.001). Furthermore, the mechanistic target of rapamycin complex 2 (mTORC2)-AKT pathway was found to negatively regulate gluconeogenesis. An AKT inhibitor was used to assess the role of the mTORC2-AKT pathway in the effects of resveratrol. The results showed resveratrol promoted hepatic gluconeogenesis by inhibiting the mTORC2-AKT pathway. Moreover, sestrin 2 (SESN2) upregulated the activity of mTORC2. We further found that resveratrol decreased SESN2 levels (P < 0.001).

CONCLUSIONS

This study indicated that resveratrol enhances the gluconeogenic capacity of calf hepatocytes by improving H2O2-induced oxidative stress and modulating the activity of the SESN2-mTORC2-AKT pathway, implying that resveratrol may be a promising target for ameliorating liver oxidative stress in transition cows.

A Descriptive Review of the Action Mechanisms of Berberine, Quercetin and Silymarin on Insulin Resistance/Hyperinsulinemia and Cardiovascular Prevention

Insulin resistance (IR) and the associated hyperinsulinemia are early pathophysiological changes which, if not well treated, can lead to type 2 diabetes, endothelial dysfunction and cardiovascular disease. While diabetes care is fairly well standardized, the prevention and treatment of IR lacks a single pharmaceutical approach and many lifestyle and dietary interventions have been proposed, including a wide range of food supplements. Among the most interesting and well-known natural remedies, alkaloid berberine and the flavonol quercetin have particular relevance in the literature, while silymarin-the active principle of the Silybum marianum thistle-was traditionally used for lipid metabolism disorders and to sustain liver function. This review describes the major defects of insulin signaling leading to IR and the main properties of the three mentioned natural substances, their molecular targets and synergistic action mechanisms. The actions of berberine, quercetin and silymarin are partially superimposable as remedies against reactive oxygen intermediates generated by a high-lipid diet and by NADPH oxidase, which is triggered by phagocyte activation. Furthermore, these compounds inhibit the secretion of a battery of pro-inflammatory cytokines, modulate intestinal microbiota and are especially able to control the various disorders of the insulin receptor and post-receptor signaling systems. Although most of the evidence on the effects of berberine, quercetin and silymarin in modulating insulin resistance and preventing cardiovascular disease derive from experimental studies on animals, the amount of pre-clinical knowledge strongly suggests the need to investigate the therapeutic potential of these substances in human pathology.

Expected and Unexpected Effects of Pharmacological Antioxidants

In this review, we have collected the existing data on the bioactivity of antioxidants (N-acetylcysteine, polyphenols, vitamin C) which are traditionally used in experimental biology and, in some cases, in the clinic. Presented data show that, despite the capacity of these substances to scavenge peroxides and free radicals in cell-free systems, their ability to exhibit these properties in vivo, upon pharmacological supplementation, has not been confirmed so far. Their cytoprotective activity is explained mainly by the ability not to suppress, but to activate multiple redox pathways, which causes biphasic hormetic responses and highly pleiotropic effects in cells. N-acetylcysteine, polyphenols, and vitamin C affect redox homeostasis by generating low-molecular-weight redox-active compounds (H₂O₂ or H₂S), known for their ability to stimulate cellular endogenous antioxidant defense and promote cytoprotection at low concentrations but exert deleterious effects at high concentrations. Moreover, the activity of antioxidants strongly depends on the biological context and mode of their application. We show here that considering the biphasic and context-dependent response of cells on the pleiotropic action of antioxidants can help explain many of the conflicting results obtained in basic and applied research and build a more logical strategy for their use.

Systemic complications of rheumatoid arthritis: Focus on pathogenesis and treatment

As a systemic autoimmune disease, rheumatoid arthritis (RA) usually causes damage not only to joints, but also to other tissues and organs including the heart, kidneys, lungs, digestive system, eyes, skin, and nervous system. Excessive complications are closely related to the prognosis of RA patients and even lead to increased mortality. This article summarizes the serious complications of RA, focusing on its incidence, pathogenesis, clinical features, and treatment methods, aiming to provide a reference for clinicians to better manage the complications of RA.

Resveratrol Inhibits Oxidative Stress and Regulates M1/M2-Type Polarization of Microglia via Mediation of the Nrf2/Shh Signaling Cascade after OGD/R Injury In Vitro

AIMS

Microglia are closely related to the occurrence and development of oxidative stress. Cerebral ischemia leads to abnormal activation of microglia. Resveratrol can regulate M1/M2-type microglia polarization, but the underlying mechanism is not well understood, although the Nrf2 and Shh signaling pathways may be involved. Given that resveratrol activates Shh, the present study examined whether this is mediated by Nrf2 signaling.

METHODS

N9 microglia were pretreated with drugs before oxygen-glucose deprivation/reoxygenation (OGD/R). HT22 neurons were also used for conditional co-culture with microglia. Cell viability was measured by CCK-8 assay. MDA levels and SOD activity in the supernatant were detected by TBA and WST-1, respectively. Immunofluorescence detected Nrf2 and Gli1 nuclear translocation. The levels of CD206, Arg1, iNOS, TNF-α, Nrf2, HO-1, NQO1, Shh, Ptc, Smo, Gli1 protein and mRNA were measured by Western blotting or RT-qPCR. Annexin V-FITC Flow Cytometric Analysis detected apoptosis.

RESULTS

Resveratrol and Nrf2 activator RTA-408 enhanced the viability of microglia, reduced oxidative stress, promoted M2-type microglia polarization and activated Nrf2 and Shh signaling. ML385, a selective inhibitor of Nrf2, decreased the viability of microglia, aggravated oxidative stress, promoted M1-type microglia polarization and inhibited Nrf2 and Shh signaling. Moreover, resveratrol and RTA-408-treated microglia can reduce the apoptosis and increase the viability of HT22 neurons, while ML385-treated microglia aggravated the apoptosis and weakened the viability of HT22 neurons.

CONCLUSIONS

These results demonstrated that resveratrol may inhibit oxidative stress, regulate M1/M2-type polarization of microglia and decrease neuronal injury in conditional co-culture of neurons and microglia via the mediation of the Nrf2/Shh signaling cascade after OGD/R injury in vitro.

Effects of Resveratrol Against Induced Metabolic Syndrome in Rats: Role of Oxidative Stress, Inflammation, and Insulin Resistance

Metabolic syndrome (MS) is a serious health problem associated with an increase in risk factors for hepatic steatosis, which is the most common liver disease today. The goal of this study was to investigate the protective effects of resveratrol against metabolic alterations associated with a high-fat high-fructose diet (HFFD). Thirty-two male rats were randomly divided into four equal groups: control (cont.), metabolic syndrome (MS), resveratrol (Res), and metabolic syndrome treated with resveratrol (MS + Res). Resveratrol was administrated orally at a dose of 30 mg/kg·bw, daily. After 10 weeks, body weight, serum biochemical parameters, hepatic oxidative stress, inflammatory markers, as well as mRNA levels of hepatic genes related to lipid metabolism and insulin signaling were measured. In addition, the liver was examined histopathologically to detect lipid deposition. Increased body weight, hepatic dysfunction, dyslipidemia, hepatic insulin resistance, hepatic oxidative and inflammatory stress conditions, upregulation of mRNA expression level of sterol regulatory element binding protein 1-c (SREBP1-c), and downregulation of mRNA expression levels of peroxisome proliferated activated receptor alpha (PPARα) and insulin receptor substrate-2 (IR-S2) were all observed in the MS rats. Hepatic steatosis was confirmed by hematoxylin and eosin and Oil Red O staining. Administration of resveratrol reduced liver steatosis, oxidative stress, and inflammatory state. Also, it improved lipid profile as well as insulin sensitivity and reverted alterations in hepatic mRNA expression levels of the tested genes. Based on these findings, resveratrol could be proposed as a therapeutic approach for MS prevention.

Effect of quercetin on muscle growth and antioxidant status of the dark sleeper Odontobutis potamophila

Quercetin is a flavanol beneficial in reducing fat, promoting muscle growth, and Anti-oxidation. To study its effects in freshwater fish, the full-length cDNA of the follistatin (FST) and myostatin (MSTN) genes of the dark sleeper Odontobutis potamophila were cloned for the first time. Juvenile individual O. potamophila was exposed to quercetin at one of four concentrations (0, 2.5, 5, and 10 mg/L) for 21 days. The expression level of MSTN which inhibits muscle growth in the quercetin solution was lower than in the unexposed control group. The genes that promote muscle growth are in TGF-β superfamily like FST, TGF-β1 (transforming growth factor-beta 1), and Myogenic regulatory factors (MRFs) like Myf5 (myogenic factor 5), MyoD (myogenic differentiation), MyoG (myogenin), were higher than in the control group. Apolipoprotein and growth hormone receptor transcription levels in the quercetin-treated fish were significantly lower than in the control group. The concentrations of triglyceride, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol in the muscle tissue decreased, and the lipid-lowering function of quercetin was also demonstrated at the biochemical level. In this study, we analyzed the mRNA levels of AKT, Keap1 (kelch-like ECH-associated protein 1), Nrf2 (NF-E2-related factor 2) oxidation-related genes in the Nrf2/ARE antioxidant pathway, and Malondialdehyde (MDA), catalase (CAT) activity and glutathione (GSH) content in the hepatopancreas of O. potamophila after quercetin treatment, the mRNA expression of AKT, Nrf2 and CAT activity and GSH content are higher than in the control group. Quercetin enhances antioxidant properties and positively affects muscle growth. The results showed that quercetin has no significant effects on the growth performance of O. potamophila, but is effective in increasing muscle growth rate and lowering muscle fat content.

The therapeutic effects and mechanisms of action of resveratrol on polycystic ovary syndrome: A comprehensive systematic review of clinical, animal, and in vitro studies

BACKGROUND

Polycystic ovary syndrome (PCOS) is one of the most important and common polygenic endocrine disorders among women of reproductive age. Resveratrol, a natural phenol, is involved in various biological activities, including antioxidant, antiseptic, anti-inflammatory, anti-aging, and anti-cancer effects.

METHODS

This systematic review aimed to investigate the therapeutic effects and mechanisms of actions of resveratrol in PCOS. The present study was conducted according to the guidelines of the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) statements. We searched PubMed, Science Direct, Google Scholar, Scopus, ISI Web of Science, ProQuest, and Embase databases up to August 2021 by using the relative keywords. Original studies published in the English language that assessed the effects of resveratrol on PCOS and its associated complications were considered. Out of 417 records screened, only 24 articles met the inclusion criteria: 10 in vitro, 10 animal, and 4 human studies.

RESULTS

The results obtained in the present study showed that resveratrol supplementation might be effective in improving PCOS-related symptoms by reducing insulin resistance, alleviating dyslipidemia, improving ovarian morphology and anthropometric indices, regulating the reproductive hormones, and reducing inflammation and oxidative stress by affecting biological pathways.

CONCLUSION

According to the available evidence, resveratrol may reduce the complications of PCOS. However, further studies are recommended for a comprehensive conclusion on the exact mechanism of resveratrol in PCOS patients. This article is protected by copyright. All rights reserved.

Redox Control of Integrin-Mediated Hepatic Inflammation in Systemic Autoimmunity

Significance: Systemic autoimmunity affects 3%-5% of the population worldwide. Systemic lupus erythematosus (SLE) is a prototypical form of such condition, which affects 20-150 of 100,000 people globally. Liver dysfunction, defined by increased immune cell infiltration into the hepatic parenchyma, is an understudied manifestation that affects up to 20% of SLE patients. Autoimmunity in SLE involves proinflammatory lineage specification in the immune system that occurs with oxidative stress and profound changes in cellular metabolism. As the primary metabolic organ of the body, the liver is uniquely capable to encounter oxidative stress through first-pass derivatization and filtering of waste products. Recent Advances: The traffic of immune cells from their development through recirculation in the liver is guided by cell adhesion molecules (CAMs) and integrins, cell surface proteins that tightly anchor cells together. The surface expression of CAMs and integrins is regulated via endocytic traffic that is sensitive to oxidative stress. Reactive oxygen species (ROS) that elicit oxidative stress in the liver may originate from the mitochondria, the cytosol, or the cell membrane. Critical Issues: While hepatic ROS production is a source of vulnerability, it also modulates the development and function of the immune system. In turn, the liver employs antioxidant defense mechanisms to protect itself from damage that can be harnessed to serve as therapeutic mechanisms against autoimmunity, inflammation, and development of hepatocellular carcinoma. Future Directions: This review is aimed at delineating redox control of integrin signaling in the liver and checkpoints of regulatory impact that can be targeted for treatment of inflammation in systemic autoimmunity. Antioxid. Redox Signal. 36, 367-388.

Autophagy as a molecular target of quercetin underlying its protective effects in human diseases

Autophagy, known as a "self-eating" process, is associated with degradation of aged or damaged components and organelles. Generally, autophagy is a survival mechanism that provides energy during nutritional deprivation. This mechanism plays a remarkable role during the physiological condition by maintaining homeostasis and energy balance and several pathological conditions, particularly neurological disorders. Due to the critical role of autophagy in cancer, much attention has been made in the regulation of autophagy using both naturally occurring and synthetic drugs. Quercetin is a plant-derived chemical belonging to the family of flavonoids. Quercetin has valuable biological and therapeutic effects such as anti-tumor, antioxidant, anti-inflammatory, anti-diabetic, hepatoprotective, and cardioprotective. At the present review, we first provide an introduction about quercetin and autophagy with its related molecular pathways. We also describe how quercetin modulates autophagy mechanism to exert its therapeutic effects.

Hepatoprotective and therapeutic effects of resveratrol: A focus on anti-inflammatory and anti- oxidative activities

Being the most essential organ in the body, the liver performs critical functions. Hepatic disorders, such as alcoholic liver disease, hepatic steatosis, liver fibrosis, non-alcoholic fatty liver disease, hepatocellular carcinoma and hepatic failure, have an impact on the biochemical and physiological functions of the body. The main representative of the flavonoid subgroup of flavones, Resveratrol (RES), exhibits suitable pharmacological activities for treating various liver diseases, such as fatty hepatitis, liver steatosis, liver cancer and liver fibrosis. According to various studies, grapes and red wine are good sources of RES. RES has various health properties; it is anti-inflammatory, anti-apoptotic, anti-oxidative and hepatoprotective against several hepatic diseases and hepatoxicity. Therefore, we performed a thorough research and created a summary of the distinct targets of RES in various stages of liver diseases. We concluded that RES inhibited liver inflammation essentially by causing a significant decrease in the expression of various pro-inflammatory cytokines like TNF-α, IL-1α, IL-1β, and IL-6. It also inhibits the transcription factor nuclear NF-κB that brings about the inflammatory cascade. RES also inhibits the PI3K/Akt/mTOR pathway to induce apoptosis. Additionally, it reduces oxidative stress in hepatic tissue by markedly reducing MDA and NO contents, and significantly increasing the levels of CAT, SOD and reduced GSH, in addition to AST and ALT, against toxic chemicals like CC14, As2O3 and TTA. Due to its anti-oxidant, anti-inflammatory and anti-fibrotic properties, RES reduces liver injury markers. RES is safe natural antioxidant that provides pharmacological rectification of the hepatoxicity of toxic chemicals.

The combined impact of decabromodiphenyl ether and high fat exposure on non-alcoholic fatty liver disease in vivo and in vitro

Non-alcoholic fatty liver disease (NAFLD) is considered a public health concern. Decabromodiphenyl ether (BDE-209) and high fat (HF) exposure cause liver injury, yet the combined impact on NAFLD development remains unclear. HepG2 cells were incubated with BDE-209 or/and HF reagent (C_{sodium oleate}/C_{sodium palmitate} = 2/1) for establishing the in vitro model, while C57BL/6 mice fed BDE-209 or/and HF diet (HFD) was the in vivo model. Oil Red O staining and the determination of triglyceride, malondialdehyde, and reactive oxygen species (ROS) contents proved the elevated lipid accumulation and oxidative stress by the mixture of BDE-209 and HF in HepG2 cells, consistent in C57BL/6 mice. Importantly, the action analysis showed the synergistic effect between BDE-209 and HF, suggesting that the population preferring the HFD is more susceptible to BDE-209 to aggravate the progression of NAFLD. Further, the increased protein expression of sterol regulatory element-binding protein 1, fatty acid synthase, and stearoyl-CoA desaturase 1 was considered to be responsible for hepatic steatosis. The impairment of antioxidant system was reflected by the lower hepatic superoxide dismutase and glutathione transferase activities and reduced glutathione level, explaining the detected excessive ROS production. Besides, using high content analysis, the decline of mitochondrial mass and membrane potential, which was closed to the NAFLD pathogenesis, was also demonstrated in HepG2 cells.

The relevance of nanotechnology, hepato-protective agents in reducing the toxicity and augmenting the bioavailability of isotretinoin

Acne Vulgaris is one of the most common chronic inflammatory skin disorders that affect majority of teen-agers worldwide. Isotretinoin (ITT) is the drug of choice in the management of acne, but, it suffers from serious side-effects including hepatotoxicity, and some psychological disturbances following its oral intake. The objective of this study was to develop and optimize ITT loaded nanoemulsions (ITT-SNEDDS) and to incorporate resveratrol (RSV)in optimum formulation to decrease ITT side effects The ITT solubility was first tested in various essential oils, surfactants, and co-surfactants to select the essential nanoemulsion ingredients. Mixture design was applied to study the effect of independent variables and their interactions on the selected dependent responses. The developed ITT-SNEDDS were characterized for their globule size and ex vivo permeation. The optimized batch was further loaded with RSV and evaluated for in vitro and ex vivo permeation and for in vivo hepatotoxicity. The developed ITT-SNEDDS exhibited globule size below 300 nm, up to 272.27 ± 7.12 mcg/cm².h and 61.27 ± 2.83% of steady-state flux (J_SS) and permeability % respectively. Optimum formulation consisted of 0.15 g oil mixture, 0.6 g of surfactant (Labrasol), and 0.250 g co-surfactant (Transcutol). Permeability studies confirmed the enhanced permeation percentage of ITT (40.77 ± 1.18%), and RSV (29.94 ± 2.02%) from optimized formulation, with enhanced steady-state flux (J_SS). In vivo studies demonstrated the superior hepatoprotective activity of optimized formulation compared to a different drug formulations and marketed product. Therefore, RVS loaded ITT-SNEDDS might be a successful strategy for acne management with improved action, and minimum side effects.

Resveratrol and Quercetin as Regulators of Inflammatory and Purinergic Receptors to Attenuate Liver Damage Associated to Metabolic Syndrome

Nonalcoholic fatty liver disease (NAFLD) is considered a manifestation of metabolic syndrome (MS) and is characterized by the accumulation of triglycerides and a varying degree of hepatic injury, inflammation, and repair. Moreover, peroxisome-proliferator-activated receptors (PPARs) play a critical role in the pathophysiological processes in the liver. There is extensive evidence of the beneficial effect of polyphenols such as resveratrol (RSV) and quercetin (QRC) on the treatment of liver pathology; however, the mechanisms underlying their beneficial effects have not been fully elucidated. In this work, we show that the mechanisms underlying the beneficial effects of RSV and QRC against inflammation in liver damage in our MS model are due to the activation of novel pathways which have not been previously described such as the downregulation of the expression of toll-like receptor 4 (TLR4), neutrophil elastase (NE) and purinergic receptor P2Y2. This downregulation leads to a decrease in apoptosis and hepatic fibrosis with no changes in hepatocyte proliferation. In addition, PPAR alpha and gamma expression were altered in MS but their expression was not affected by the treatment with the natural compounds. The improvement of liver damage by the administration of polyphenols was reflected in the normalization of serum transaminase activities.

Role of Quercetin in Depressive-Like Behaviors: Findings from Animal Models

Depressive-like behavior is a highly prevalent worldwide neuropsychiatric disorder that owns a complex pathophysiologic mechanism. The available pharmacotherapy is ineffective for most patients and shown several adverse effects. Therefore, it is important to find efficacy and safe antidepressive compounds. Some phytochemicals compounds regulate the same genes and pathways targeted by drugs; therefore, diets rich in fruits and vegetables could be considered novel treatment approaches. Currently, the functional properties of quercetin acquired great interest, due to its beneficial effects on health. Quercetin is a flavonoid ubiquitously present in vegetables and fruits, interestingly for its strong antioxidant properties. The purpose of this review is to summarize the preclinical studies present in the literature, in the last ten years, aimed at illustrating the effects of quercetin pre-treatment in depressive-like behaviors. Quercetin resulted in antidepressant-like actions due to its antioxidant, anti-inflammatory, and neuroprotective effects. This pointed out the usefulness of this flavonoid as a nutraceutical compound against the development of psychological stress-induced behavioral perturbation. Therefore, quercetin or a diet containing it may become a prospective supplementation or an efficient adjuvant therapy for preventing stress-mediated depressive-like behavior.

Açaí (Euterpe oleracea Martius) supplementation improves oxidative stress biomarkers in liver tissue of dams fed a high-fat diet and increases antioxidant enzymes' gene expression in offspring

Lipids excess from an uterine environment can increase free radicals production of and thus induce oxidative status imbalance, a key factor for progression of non-alcoholic fatty liver disease (NAFLD) in offspring. Food antioxidant components in maternal diet may play an important role in preventing offspring metabolic disorders. The objective of the study was to evaluate the effects of açaí pulp supplementation on maternal high-fat diet, by assessing activity and expression of antioxidant enzymes and biomarkers of oxidative stress in the liver. Female Fisher rats were divided into four groups and fed a control diet (C), a high-fat diet (HF), a control diet supplemented with açaí (CA) and a high-fat diet supplemented with açaí (HFA) before mating, during gestation and lactation. The effects of açaí supplementation on oxidative stress biomarkers and antioxidant enzymes expression were evaluated in dams and male offspring after weaning. HFA diet increased body weight in dams, however reduced absolute and relative liver weight. There was a reduction in liver biomarkers of oxidative stress, malondialdehyde and carbonyl protein, as well as in catalase, glutathione peroxidase and superoxide dismutase activity. In offspring, HFA diet reduced liver weight and increased Gpx1, Gpx4 and Sod1 mRNA expression. These results suggest that açaí is able to restore redox status, preventing oxidative damage in dams by a direct mechanism and to promote beneficial effects on expression of antioxidant defences related genes in offspring.

Modulation of Renal Function in a Metabolic Syndrome Rat Model by Antioxidants in Hibiscus sabdariffa L

Metabolic syndrome (MS) is the association of three or more pathologies among which obesity, hypertension, insulin resistance, dyslipidemia, and diabetes are included. It causes oxidative stress (OS) and renal dysfunction. Hibiscus sabdariffa L. (HSL) is a source of natural antioxidants that may control the renal damage caused by the MS. The objective of this work was to evaluate the effect of a 2% HSL infusion on renal function in a MS rat model induced by the administration of 30% sucrose in drinking water. 24 male Wistar rats were divided into 3 groups: Control rats, MS rats and MS + HSL rats. MS rats had increased body weight, systolic blood pressure, triglycerides, insulin, HOMA index, and leptin (p ≤ 0.04). Renal function was impaired by an increase in perfusion pressure in the isolated and perfused kidney, albuminuria (p ≤ 0.03), and by a decrease in clearance of creatinine (p ≤ 0.04). The activity of some antioxidant enzymes including the superoxide dismutase isoforms, peroxidases, glutathione peroxidase, glutathione-S-transferase was decreased (p ≤ 0.05). Lipoperoxidation and carbonylation were increased (p ≤ 0.001). The nitrates/nitrites ratio, total antioxidant capacity, glutathione levels and vitamin C were decreased (p ≤ 0.03). The treatment with 2% HSL reversed these alterations. The results suggest that the treatment with 2% HSL infusion protects renal function through its natural antioxidants which favor an improved renal vascular response. The infusion contributes to the increase in the glomerular filtration rate, by promoting an increase in the enzymatic and non-enzymatic antioxidant systems leading to a decrease in OS and reestablishing the normal renal function.

Quercetin mitigates ethanol-induced hepatic steatosis in zebrafish via P2X7R-mediated PI3K/ Keap1/Nrf2 signaling pathway

Ethnopharmacological relevanceQuercetin is the active component of the higher content in PCP, which exerts various biological activities such as anti-obesity effect, anti-inflammatory and anti-oxidant activities in alcoholic liver disease (ALD).

AIM OF THE STUDY

P2X7 receptor (P2X7R) plays an important role in health and disease, which can be activated by extracellular ATP to induce a variety of downstream events, including lipid metabolism, inflammatory molecule release, oxidative stress. However, whether the mechanism of quercetin on ethanol-induced hepatic steatosis via P2X7R-mediated haven't been elucidated.

MATERIAL AND METHODS

Zebrafish transgenic (fabp10: EGFP) larvae were treated with 100 μM, 50 μM, 25 μM quercetin for 48 h at 3 days post fertilization (dpf), then soaked in 350 mmol/L ethanol for 32 h, treated with 1 mM ATP (P2X7R activator) for 30min. Serum lipids, liver steatosis, oxidative stress factors were respectively detected. The mRNA levels in the related pathways were measured by quantitative Real-Time PCR (RT-qPCR) to investigate the mechanisms.

RESULTS

Quercetin improved the liver function via decreasing ALT, AST and γ-GT level of zebrafish with acute ethanol-induced hepatic steatosis and attenuated hepatic TG, TC accumulation. Additionally, quercetin significantly reduced the MDA content and suppressed the ethanol-induced reduction of hepatic oxidative stress biomarkers GSH, CAT and SOD and significantly down-regulated the expression of P2X7R, and up-regulated the expression of phosphatidylinositol 3-kinase (PI3K), Kelch like ECH associated protein1 (Keap1), Nuclear Factor E2 related factor 2 (Nrf2). Moreover, ATP stimulation activated P2X7R, which further mediated the mRNA expressions of PI3K, Keap1 and Nrf2.

CONCLUSION

Quercetin exhibited hepatoprotective capacity in zebrafish model, via regulating P2X7R-mediated PI3K/Keap1/Nrf2 oxidative stress signaling pathway.

Oxidative Stress, Plant Natural Antioxidants, and Obesity

Oxidative stress is important in the pathophysiology of obesity, altering regulatory factors of mitochondrial activity, modifying the concentration of inflammation mediators associated with a large number and size of adipocytes, promoting lipogenesis, stimulating differentiation of preadipocytes to mature adipocytes, and regulating the energy balance in hypothalamic neurons that control appetite. This review discusses the participation of oxidative stress in obesity and the important groups of compounds found in plants with antioxidant properties, which include (a) polyphenols such as phenolic acids, stilbenes, flavonoids (flavonols, flavanols, anthocyanins, flavanones, flavones, flavanonols, and isoflavones), and curcuminoids (b) carotenoids, (c) capsaicinoids and casinoids, (d) isothiocyanates, (e) catechins, and (f) vitamins. Examples are analyzed, such as resveratrol, quercetin, curcumin, ferulic acid, phloretin, green tea, Hibiscus Sabdariffa, and garlic. The antioxidant activities of these compounds depend on their activities as reactive oxygen species (ROS) scavengers and on their capacity to prevent the activation of NF-κB (nuclear factor κ-light-chain-enhancer of activated B cells), and reduce the expression of target genes, including those participating in inflammation. We conclude that natural compounds have therapeutic potential for diseases mediated by oxidative stress, particularly obesity. Controlled and well-designed clinical trials are still necessary to better know the effects of these compounds.

Diagnostic Criteria for Metabolic Syndrome in Diet-Induced Rodent Models: A Systematic Review

BACKGROUND

Thousands of publications in recent years have addressed the induction of metabolic syndrome (MetS) in rodents. However, the criteria and the reference values for diagnosing this disease have not been defined.

OBJECTIVE

Our main objective was to carry out a systematic review to gather evidence about the criteria for biochemical and anthropometric parameters in which scientific studies have relied on to report that rats developed MetS from a previous dietary manipulation.

METHODS

We compiled characteristics and findings of diet-induced MetS with high-fat, high-carbohydrate, high-fat/high-carbohydrates, and cafeteria diet from PubMed and Science Direct databases published in the last 5 years.

RESULTS

The results on the principal determinants for the syndrome, published in the reviewed articles, were chosen to propose reference values in the rat models of food induction.

CONCLUSION

The values obtained will serve as reference cut-of points in the development of the disease; in addition, the compilation of data will be useful in planning and executing research protocols in animal models.

Self-Nanoemulsion Loaded with a Combination of Isotretinoin, an Anti-Acne Drug, and Quercetin: Preparation, Optimization, and In Vivo Assessment

Acne vulgaris is a common skin disease that affects everybody at least once in their lives. The treatment is challenging because the stratum corneum contains rigid corneocytes surrounded by intercellular lamellae that are difficult to bypass. In the present study, we intended to formulate an effective nanoemulsion that could deliver isotretinoin (ITT) with enhanced solubility, permeability, and bioavailability across the skin. ITT can have a serious hepatotoxic effect if given too frequently or erratically. Therefore, to overcome the aforesaid limitation, quercetin (QRS), a hepatoprotective agent, was incorporated into the formulation. Initially, the ITT solubility was determined in various surfactants and cosurfactants to select the essential ingredients to be used in the formulation and to optimize a nanoemulsion that could enhance the solubility and permeability of ITT and its antimicrobial activity against Staphyloccocus aureus, which is the main microorganism responsible for acne vulgaris. The mixture design was applied to study the interactions and optimize the independent variables that could match the prerequisites of selected dependent responses. A formulation containing 0.25 g of rosehip oil, 0.45 g of surfactant (Lauroglycol-90), and 0.3 g of cosurfactant (propylene glycol) was chosen as an optimized desirable formulation. The optimized batch was loaded with QRS and evaluated for in vitro and ex vivo permeation. The in vivo hepatotoxicity was assessed through topical administration. Permeability studies confirmed the enhanced permeation percentage of ITT (52.11 ± 2.85%) and QRS (25.44 ± 3.18%) of the optimized formulation, with an enhanced steady-state flux (Jss). The in vivo studies conducted on experimental animals demonstrated superior hepatoprotective activity of the prepared optimized formulation compared with other formulations of drugs and commercially marketed products. We anticipate that this optimized ITT formulation, followed up with good clinical evaluations, can be a breakthrough in the safe treatment of acne vulgaris.

Honey protects against chronic unpredictable mild stress induced- intestinal barrier disintegration and hepatic inflammation

Chronic stress is linked to liver injury by increasing intestinal permeability to lipopolysaccharide (LPS), which in turn can result in systemic and liver inflammation and damage. Beneficial effect of honey in the prevention of liver injury has been shown in previous studies, but mechanisms underlying are still less known. Here, we examined the therapeutic impacts of honey on intestinal nuclear factor-κB (NF-κB; an important regulator of stress-induced immune and inflammatory responses) and ileal tight junction (TJ) proteins of claudin-1 and ZO-1, serum LPS, liver inflammation and oxidative markers of malondialdehyde (MDA), nitric oxide (NO), (erythroid-derived 2)-like 2 (Nrf2), tumor necrosis factor (TNF)-α and total antioxidant capacity (TAC) following chronic unpredictable mild stress (CUMS) using Western blotting, ELISA kit and spectrophotometry. Male rats were subjected to CUMS for 28 consecutive days. Honey (0.2 and 2 g/kg/day, by gavage) was administered pretreatment (10 days) and during stress. Honey reduced stress-induced LPS elevation by preventing reduction in the intestinal TJ proteins of claudin-1 and ZO-1, while did not affect NF-kB levels. In liver, honey significantly suppressed stress-induced increase in MDA, NO, TNF-α and Nrf2 expression and normalized TAC. Noteworthy, honey high-dose provoked a greater decrease in TNF-α, Nrf2 and LPS levels than honey low-dose. Together, our study indicated that honey protects against stress-induced liver damage by modulating at least two pathways; intestinal barrier protection via increased TJ protein complex expression, and hepatic TAC protection that may be involved in the inhibition of MDA, NO, TNF-α and Nrf2 expression.

An Overview of the Mechanism of Penthorum chinense Pursh on Alcoholic Fatty Liver

Alcohol liver disease (ALD) caused by excessive alcohol consumption is a progressive disease, and alcohol fatty liver disease is the primary stage. Currently, there is no approved drug for its treatment. Abstinence is the best way to heal, but patients' compliance is poor. Unlike other chronic diseases, alcohol fatty liver disease is not caused by nutritional deficiencies; it is caused by the molecular action of ingested alcohol and its metabolites. More and more studies have shown the potential of Penthorum chinense Pursh (PCP) in the clinical use of alcohol fatty liver treatment. The purpose of this paper is to reveal from the essence of PCP treatment of alcohol liver mechanism mainly by the ethanol dehydrogenase (ADH) and microsomal ethanol oxidation system-dependent cytochrome P4502E1 (CYP2E1) to exert antilipogenesis, antioxidant, anti-inflammatory, antiapoptotic, and autophagy effects, with special emphasis on its mechanisms related to SIRT1/AMPK, KEAP-1/Nrf2, and TLR4/NF-κB. Overall, data from the literature shows that PCP appears to be a promising hepatoprotective traditional Chinese medicine (TCM).

Erica multiflora extract rich in quercetin-3-O-glucoside and kaempferol-3-O-glucoside alleviates high fat and fructose diet-induced fatty liver disease by modulating metabolic and inflammatory pathways in Wistar rats

The wide morbidity of obesity has heightened interest in providing natural and safe compounds to maintain optimal health. The present study was designed to determine the chemical constituents and the effects of methanol leaf extract from Erica multiflora (M-EML) on mitigating high-fat and high-fructose diet (HFFD)-induced metabolic syndrome (MS). LC-MS/MS characterization of M-EML allowed the identification of 14 secondary metabolites and showed that quercetin-3-O-glucoside and kaempferol-3-O-glucoside were the main compounds of our extract. In the in vivo study, the oral administration of M-EML (250 mg/kg) during the last 4 weeks of the experimentation alleviated HFFD-induced obesity, insulin resistance (IR) and cardiovascular diseases. Thus, M-EML treatment significantly normalized body and liver weight, allowed to a sharp decline in plasma levels of TC, TG and LDL-c by 32%, 35% and 66%, respectively. Moreover, hepatic enzymes, total and direct bilirubin, lipase and uric acid levels have been diminished in treated group. Histopathology of the liver confirmed the changes induced by HFFD and the hepatoprotective effect of M-EML. The supply of M-EML reduced NO production and cellular lysosomal enzyme activity by 44% and 60%, respectively compared to HFFD. Besides, M-EML showed decreased pro-inflammatory cytokines levels (259.5±47.35 pg/ml and 56.08±1.56 pg/ml) of TNF-α and IL-6, respectively. In addition, M-EML reduced liver malondialdehyde (MDA) content and enhanced superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) activities. In contrast, these enzymatic activities have been disrupted in HFFD rats. Overall, M-EML prevented obesity through the modulation of metabolic syndrome, reducing inflammation and promoting antioxidant enzymes activities.

Metabolic Impact of Flavonoids Consumption in Obesity: From Central to Peripheral

The prevention and treatment of obesity is primary based on the follow-up of a healthy lifestyle, which includes a healthy diet with an important presence of bioactive compounds such as polyphenols. For many years, the health benefits of polyphenols have been attributed to their anti-oxidant capacity as free radical scavengers. More recently it has been described that polyphenols activate other cell-signaling pathways that are not related to ROS production but rather involved in metabolic regulation. In this review, we have summarized the current knowledge in this field by focusing on the metabolic effects of flavonoids. Flavonoids are widely distributed in the plant kingdom where they are used for growing and defensing. They are structurally characterized by two benzene rings and a heterocyclic pyrone ring and based on the oxidation and saturation status of the heterocyclic ring flavonoids are grouped in seven different subclasses. The present work is focused on describing the molecular mechanisms underlying the metabolic impact of flavonoids in obesity and obesity-related diseases. We described the effects of each group of flavonoids in liver, white and brown adipose tissue and central nervous system and the metabolic and signaling pathways involved on them.

Quercetin mitigates monosodium glutamate-induced excitotoxicity of the spinal cord motoneurons in aged rats via p38 MAPK inhibition

Various studies reported the possibility of deterioration of blood-brain barrier (BBB) integrity owing to the aging process. The current work was performed to investigate the ability of Monosodium glutamate (MSG) to cross BBB in aged rats, the damage affecting the anterior horn cells of the spinal cord due to excitotoxicity, and the mechanisms by which quercetin (Que) administration might suppress such damage. Forty male rats aged 18 months were assigned equally to 4 groups: control group, Que group (received Que, 20 mg/kg/d intraperitonealy for 10 days), MSG group (received MSG, 4.0 g/kg/d subcutaneously for 10 days), MSG + Que group (received both Que and MSG as done in the Que and MSG groups respectively). Cervical spinal cord specimens were obtained and prepared for routine histological study, immunohistochemical staining by caspase-3 and glial fibrillary acidic protein (GFAP), assessment of oxidative stress, measurement of cytokines, assessment of caspase-3 activity and GFAP levels as well as for western blotting of phosphorylated activating transcription factor 2 (ATF2^pp) as an indicator for the activity of p38 mitogen-activated protein kinase (MAPK). The MSG group revealed variable degenerative and apoptotic changes in the motoneurons and neuroglia, a marked rise in the cytoplasmic caspase-3 expression in motoneurons and a significant reduction (p < 0.001) in the astrocyte surface area percentage. In addition, the spinal cord tissue exhibited a significant elevation (p < 0.001) in the levels of malondialdehyde (MDA), IL-1, IL-6, TNFα, INFɣ, caspase-3 activity and ATF2 ^pp expression as well as a significant reduction (p < 0.001) in SOD, IL-10 and GFAP levels compared with the control group. On combining Que with MSG, most of the degenerative changes were reversed and all the impaired parameters were nearly normalized except for IL-6 and GFAP levels which were still significantly (p < 0.05) different from those of the control group. Our study suggests that MSG can break through the BBB of the aged rats and induce excitotoxicity dependent changes in spinal cord motoneurons. Most of these changes were reversed by Que probably via targeting the p38 MAPK-ATF2 pathway, antagonizing oxidative stress, anti-inflammatory effect, and promoting GFAP expression.

The therapeutic effect of resveratrol: Focusing on the Nrf2 signaling pathway

Resveratrol is a natural polyphenol derived from grapes, berries, red wine, peanuts amongst other fruits and nuts. Beneficial effects such as anti-inflammatory, antioxidant, hepatoprotective, neuroprotective, cardioprotective, renoprotective, anti-obesity, anti-diabetic, and anti-cancer of resveratrol have been demonstrated by preclinical and clinical research. A possibility is that these therapeutical effects are associated with modulation of the Nrf2 signaling pathway in the following way: resveratrol may potentiate Nrf2 signaling through blockage of Keap1, by means of changing the Nrf2 mediators, its expression and its nuclear translocation. This article reviews the evidence of the Nrf2 modulating hypothesis as a possible molecular mechanism underlying the medicinal properties of resveratrol.

Effect of a Resveratrol/Quercetin Mixture on the Reversion of Hypertension Induced by a Short-Term Exposure to High Sucrose Levels Near Weaning and a Long-Term Exposure That Leads to Metabolic Syndrome in Rats

Hypertension is an important global public health problem. Excess sucrose during a short period near weaning (short sucrose period, SSP; sucrose during rat postnatal days 12 to 28) increases the risk of developing hypertension during adulthood and sucrose ingestion for 6 months after weaning also results in metabolic syndrome (MS) accompanied by hypertension. The aim of this study was to test if the mechanisms that lead to hypertension induced by SSP and MS are similarly modified by a resveratrol/quercetin mixture (RSV/QSC) that targets epigenetic cues. We studied the reversion of hypertension by an RSV/QSC mixture administered for 1 month (from month 6 to month 7 of age) in these two models, since it is effective against some signs of MS. RSV/QSC might determine Sirtuin 1 (SIRT1) and Sirtuin 3 (SIRT3) expression that modulates the expression of endothelial nitric oxide synthase (eNOS), which synthesizes nitric oxide (NO), and of superoxide dismutases (SOD1 and 2), which are antioxidant enzymes that have an impact on the NO levels. Short- (SSP) and long-term (MS) exposure to sucrose induced hypertension and RSV/QSC reversed it. It increased the insulin sensitivity, which may determine the eNOS expression. eNOS expression was decreased in aortas from SSP and MS rats and RSV/QSC only elevated its levels in aortas from MS rats. SIRT1 was also only increased in the MS aortas. Hypertension was accompanied by a decrease in total non-enzymatic antioxidant defenses in SSP and MS aortas, which improved with the RSV/QSC treatment. SOD1 expression was not modified by the sucrose treatments, but SOD2 expression was decreased in SSP and MS aortas. The RSV/QSC treatment increased SOD1 expression in MS aortas. SIRT3 was not modified by the sucrose or RSV/QSC treatments. In conclusion, SSP and MS lead to hypertension, but MS leads to more possible epigenetically- regulated mechanisms related to high blood pressure that could be targeted by the RSV/QSC mixture. Therefore, treatment has better effects on hypertension produced by MS.

Potential Adverse Effects of Resveratrol: A Literature Review

Due to its health benefits, resveratrol (RE) is one of the most researched natural polyphenols. Resveratrol's health benefits were first highlighted in the early 1990s in the French paradox study, which opened extensive research activity into this compound. Ever since, several pharmacological activities including antioxidant, anti-aging, anti-inflammatory, anti-cancerous, anti-diabetic, cardioprotective, and neuroprotective properties, were attributed to RE. However, results from the available human clinical trials were controversial concerning the protective effects of RE against diseases and their sequelae. The reason for these conflicting findings is varied but differences in the characteristics of the enrolled patients, RE doses used, and duration of RE supplementation were proposed, at least in part, as possible causes. In particular, the optimal RE dosage capable of maximizing its health benefits without raising toxicity issues remains an area of extensive research. In this context, while there is a consistent body of literature on the protective effects of RE against diseases, there are relatively few reports investigating its possible toxicity. Indeed, toxicity and adverse effects were reported following consumption of RE; therefore, extensive future studies on the long-term effects, as well as the in vivo adverse effects, of RE supplementation in humans are needed. Furthermore, data on the interactions of RE when combined with other therapies are still lacking, as well as results related to its absorption and bioavailability in the human body. In this review, we collect and summarize the available literature about RE toxicity and side effects. In this process, we analyze in vitro and in vivo studies that have addressed this stilbenoid. These studies suggest that RE still has an unexplored side. Finally, we discuss the new delivery methods that are being employed to overcome the low bioavailability of RE.

The Fluid Aspect of the Mediterranean Diet in the Prevention and Management of Cardiovascular Disease and Diabetes: The Role of Polyphenol Content in Moderate Consumption of Wine and Olive Oil

A growing interest has emerged in the beneficial effects of plant-based diets for the prevention of cardiovascular disease, diabetes and obesity. The Mediterranean diet, one of the most widely evaluated dietary patterns in scientific literature, includes in its nutrients two fluid foods: olive oil, as the main source of fats, and a low-to-moderate consumption of wine, mainly red, particularly during meals. Current mechanisms underlying the beneficial effects of the Mediterranean diet include a reduction in inflammatory and oxidative stress markers, improvement in lipid profile, insulin sensitivity and endothelial function, as well as antithrombotic properties. Most of these effects are attributable to bioactive ingredients including polyphenols, mono- and poly-unsaturated fatty acids. Polyphenols are a heterogeneous group of phytochemicals containing phenol rings. The principal classes of red wine polyphenols include flavonols (quercetin and myricetin), flavanols (catechin and epicatechin), anthocyanin and stilbenes (resveratrol). Olive oil has at least 30 phenolic compounds. Among them, the main are simple phenols (tyrosol and hydroxytyrosol), secoroids and lignans. The present narrative review focuses on phenols, part of red wine and virgin olive oil, discussing the evidence of their effects on lipids, blood pressure, atheromatous plaque and glucose metabolism.

Resveratrol targeting the Wnt signaling pathway: A focus on therapeutic activities

Wingless-type MMTV integration site (Wnt) signaling pathway is considered as an important pathway regulating a variety of biological processes such as tissue formation and homeostasis, cell proliferation, cell migration, cell differentiation, and embryogenesis. Impairment in the Wnt signaling pathway is associated with pathological conditions, particularly cancer. So, modulation of this pathway can be considered as a promising strategy and several drugs have been developed in line with this strategy. Resveratrol (Res) is a naturally occurring nutraceutical compound exclusively found in different fruits and nuts such as grape, peanut, and pistachio. This compound has favorable biological and therapeutic activities such as antioxidant, anti-inflammatory, antitumor, hepatoprotective, cardioprotective, and antidiabetic. At the present review, we demonstrate how Res modulates Wnt signaling pathway to exert its pharmacological effects.

The effects of l-Carnosine on development of metabolic syndrome in rats

AIMS

The prevalence of metabolic syndrome (MetS) is increasing in several countries. The MetS is characterized by the occurrence of at least three of the following risk factors: decreased high-density lipoprotein cholesterol, increased blood pressure, raised fasting blood glucose, elevated triglycerides, and abdominal obesity. There is a growing evidence of the role of l-carnosine in improving lipid profile and enhancement of the antioxidant activity. However, the effects of l-carnosine on development of MetS are unknown.

MAIN METHODS

Male Wistar rats were randomly assigned to receive either; conventional diet (control), high-fat high-carbohydrate diet (HFHCD), l-carnosine and conventional diet (L-Car), or l-carnosine and high-fat high-carbohydrate diet (HFHCD and L-Car) for 16 weeks. Central obesity, systolic blood pressure, lipid profile, glucose hemostasis, levels of leptin and adiponectin were evaluated on week 16.

KEY FINDINGS

Rats that received HFHCD for 16 weeks showed MetS phenotype such as central obesity, increased blood pressure and glucose, as well as an altered lipid profile (P < 0.05). l-Carnosine supplementation to MetS rats significantly reduced abdominal obesity, blood pressure and glucose, and normalized total cholesterol and low density lipoprotein cholesterol levels (P < 0.05). Insulin, leptin and adiponectin concentrations were not affected by l-Carnosine (P > 0.05).

SIGNIFICANCE

l-carnosine has beneficial effects on ameliorating the manifestations of MetS in rats.

Prospective role of mitochondrial apoptotic pathway in mediating GMG-ITC to reduce cytotoxicity in H2O2-induced oxidative stress in differentiated SH-SY5Y cells

The antioxidant and neuroprotective activity of Glucomoringin isothiocyanate (GMG-ITC) have been reported in in vivo and in vitro models of neurodegenerative diseases. However, its neuroprotective role via mitochondrial-dependent pathway in a noxious environment remains unknown. The main objective of the present study was to unveil the mitochondrial apoptotic genes' profile and prospectively link with neuroprotective activity of GMG-ITC through its ROS scavenging. The results showed that pre-treatment of differentiated SH-SY5Y cells with 1.25 μg/mL purified isolated GMG-ITC, significantly reduced reactive oxygen species (ROS) production level, compared to H₂O₂ control group, as evidenced by flow cytometry-based evaluation of ROS generation. Presence of GMG-ITC prior to development of oxidative stress condition, downregulated the expression of cyt-c, p53, Apaf-1, Bax, CASP3, CASP8 and CASP9 genes with concurrent upregulation of Bcl-2 gene in mitochondrial apoptotic signalling pathway. Protein Multiplex revealed significant decreased in cyt-c, p53, Apaf-1, Bax, CASP8 and CASP9 due to GMG-ITC pre-treatment in oxidative stress condition. The present findings speculated that pre-treatment with GMG-ITC may alleviate oxidative stress condition in neuronal cells by reducing ROS production level and protect the cells against apoptosis via neurodegenerative disease potential pathways.

Bioprocessed Production of Resveratrol-Enriched Rice Wine: Simultaneous Rice Wine Fermentation, Extraction, and Transformation of Piceid to Resveratrol from Polygonum cuspidatum Roots

A new bioprocess to produce resveratrol-enriched rice wine was established and the effects of adding Polygonum cuspidatum root powder to rice wine fermentation were investigated. In this new process, piceid and resveratrol were extracted from P. cuspidatum roots to rice wine and piceid was converted to resveratrol by β-glucosidase during fermentation. After 10 days co-fermentation, rice wine with high levels of resveratrol was obtained, which contained ~14% (v/v) ethanol, 122 mg/L piceid, and 86 mg/L resveratrol. The resveratrol-enriched rice wine had enhanced antioxidant activity with significantly stronger 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, ferric ion reducing power, and ferrous ion chelating capability. Ultrafiltration (UF) was employed in this study using hollow fibers to clarify the end product, increase shelf life without heat treatment, and maintain the quality of the phenolic compounds. The boiled and UF-treated rice wine were evaluated for ethanol, piceid, resveratrol, clarity, aerobic plate count, total acidity, pH, reducing sugars, and amino acids. The quality of the resveratrol-enriched rice wine was maintained after four weeks storage at normal refrigeration temperatures.

Intra-Abdominal Fat Adipocyte Hypertrophy through a Progressive Alteration of Lipolysis and Lipogenesis in Metabolic Syndrome Rats

This study evaluates the progressive participation of enzymes involved in lipolysis and lipogenesis, leading to adipocyte hypertrophy in a metabolic syndrome (MS) rat model caused by chronic consumption of 30% sucrose in drinking water. A total of 70 male Wistar rats were divided into two groups: C and MS. Each of these groups were then subdivided into five groups which were sacrificed as paired groups every month from the beginning of the treatment until 5 months. The intra-abdominal fat was dissected, and the adipocytes were extracted. Lipoprotein lipase (LPL), hormone-sensitive lipase (HSL), protein kinases A (PKA), and perilipin A expressions were determined. The LPL and HSL activities were evaluated by spectrophotometry. Histological staining was performed in adipose tissue. Significant increases were observed in blood pressure, HOMA-IR, leptin, triglycerides, insulin, intra-abdominal fat, and number of fat cells per field (p = 0.001) and in advanced glycosylation products, adipocyte area, LPL, HSL activities and/or expression (p ≤ 0.01) in the MS groups progressively from the third month onward. Lipogenesis and lipolysis were increased by LPL activity and HSL activity and/or expression. This was associated with hyperinsulinemia and release of non-esterified fatty acids causing a positive feedback loop that contributes to the development of adipocyte hypertrophy.