Effects of resveratrol on glucose control and insulin sensitivity in subjects with type 2 diabetes: systematic review and meta-analysis

Oxidative stress of mitophagy in neurodegenerative diseases: Mechanism and potential therapeutic targets

Neurodegenerative diseases are now significant chronic progressive neurological conditions that affect individuals' physical health. Oxidative stress is crucial in the development of these diseases. Among the various neurodegenerative diseases, mitochondrial damage has become a major factor in oxidative stress and disease advancement. During this process, oxidative stress and mitophagy plays an important role. In this paper, we introduced the role of mitophagy and oxidative stress in detail, and expounded the relationship between them. In addition, we summarized the pathogenesis of some neurodegenerative diseases and the mechanism of three antioxidants. The former includes AD, PD, HD and ALS, while the latter includes carnosine, adiponectin and resveratrol. Provide goals and directions for further research and treatment of neurodegenerative diseases. This review summarizes the impact of oxidative stress on neurodegenerative diseases by regulating mitophagy, provides a deeper understanding of their pathological mechanisms, and suggests potential new therapeutic targets.

In vivo modification of the enamel pellicle and saliva resveratrol levels after use of resveratrol-containing orodispersible capsules

OBJECTIVES

To evaluate in vivo 1) the bioavailability of trans-resveratrol when administered through sublingual capsules; 2) the effect of resveratrol on the protein composition of the acquired enamel pellicle (AEP).

DESIGN

Ten volunteers received a sublingual capsule containing 50 mg of trans-resveratrol. Unstimulated saliva was then collected after 0, 30, 60, and 120 min and AEP was collected after 120 min following administration of the capsule. In the next week, the volunteers received a placebo sublingual capsule, and saliva and AEP were collected again. Saliva samples were analyzed for free trans-resveratrol using high-performance liquid chromatopgraphy (HPLC), and AEP samples were subjected to proteomic analysis (nLC-ESI-MS/MS).

RESULTS

Trans-resveratrol was detected in saliva at all the time points evaluated, with the peak at 30 min. A total of 242 proteins were identified in both groups. Ninety-six proteins were increased and 23 proteins were decreased in the Resveratrol group. Among the up-regulated proteins, isoforms of cystatins, PRPs, Mucin-7, Histatin-1, Lactotrasnferrin and Lysozyme-C were increased and the isoforms of Protein S100, Neutrophil defensins, Albumin, PRPs, and, Statherin were decreased in Resveratrol group.

CONCLUSION

The sublingual capsule is effective at increasing the bioavailability of trans-resveratrol in saliva. Several proteins involved in important processes to maintain systemic and oral health homeostasis were identified. These proteins differently expressed due to the presence of trans-resveratrol deserve attention for future studies, since they have important functions, mainly related to antimicrobial action.

Resveratrol activates MAPK/ERK pathway to regulate oestrogen metabolism in type I endometrial cancer

OBJECTIVE

Endometrial cancer (EC) is an oestrogen-dependent tumour, the occurrence of which is closely related to an imbalance of oestrogen homeostasis. Our previous studies explored the effects of Resveratrol(Res) on oestrogen metabolism. However, systematic research on the exact mechanism of action of Res is still lacking. Based on network pharmacology, molecular docking and animal experiments, the effects and molecular mechanisms of Res on endometrial cancer were investigated.

METHODS

The target of Res was obtained from the high-throughput experiment and reference-guided database of TCM (HERB) and the Encyclopedia of Traditional Chinese Medicine (ETCM) databases, and the target of endometrial cancer was obtained by using the Genecards database. Venny map was used to obtain the intersection target of Res in the treatment of endometrial cancer, and the protein interaction network of the intersection target was constructed by importing the data into the STRING database. Then, the drug-disease-target interaction network was constructed based on Cytoscape 3.9.1 software. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed for intersection targets using the OmicShare cloud platform. Res and core targets were analysed by molecular docking. EC model mice induced by MNNG were randomly divided into the control group, Res group, MNNG group, MNNG + Res group, and MNNG + Res + MAPK/ERKi group. The protein levels of ERK and p-ERK in the mouse uterus were detected by Western blot. The levels of E1, E2, E3, 16-epiE3, 17-epiE3, 2-MeOE1, 4-MeOE1, 2-MeOE2, 4-MeOE2, 3-MeOE1, 2-OHE1, 4-OHE1, 2-OHE2, 4-OHE2, and 16α-OHE1 in the serum and endometrial tissue of mice were measured by LC‒MS/MS.

RESULTS

A total of 174 intersection targets of Res anti-endometrial cancer were obtained. The signalling pathways analysed by KEGG enrichment included the AGE-RAGE signalling pathway in diabetic complications, the PI3K-Akt signalling pathway and the MAPK signalling pathway. The top 10 core targets were MAPK3, JUN, TP53, CASP3, TNF, IL1B, AKT1, FOS, VEGFA and INS. Molecular docking showed that in addition to TNF, other targets had good affinity for Res, and the binding activity with MAPK3 was stable. Western blot results showed that Res increased the phosphorylation level of ERK and that MAPK/ERKi decreased ERK activation. In the LC-MS/MS analysis, the levels of 2-MeOE1, 2-MeOE2 and 4-MeOE1 in serum and uterine tissue showed a significantly decreasing trend in the MNNG group, while that of 4-OHE2 was increased (P < 0.05). The concentrations of 4-MeOE1 in serum and 2-MeOE1 and 2-MeOE2 in the endometrial tissue of mice were significantly increased after Res treatment, and those of 4-OHE2 in the serum and uterus of mice were significantly decreased (P < 0.05). Meanwhile, in the MAPK/ERKi intervention group, the effect of Res on the reversal of oestrogen homeostasis imbalance was obviously weakened.

CONCLUSION

Res has multiple targets and multiple approaches in the treatment of endometrial cancer. In this study, it was found that Res regulates oestrogen metabolism by activating the MAPK/ERK pathway. This finding provides a new perspective for subsequent research on the treatment of endometrial cancer.

Resveratrol Effects on Metabolic Syndrome Features: A Systematic Review and Meta-Analysis

Resveratrol is a natural polyphenol with important anti-inflammatory and antioxidant properties for treating cardiometabolic disorders. Therefore, the present meta-analysis aimed to review and investigate the oral resveratrol supplementation effects on metabolic syndrome (MetS) components. The bibliographic search was carried out in 2023 in the following databases: PubMed, Web of Science, and Scopus. Studies that investigated the oral resveratrol effects on the MetS parameters were included. Statistical analyses were performed using RevMan Software V.5.3. The main findings showed that resveratrol significantly decreased systolic and diastolic blood pressure while having no significant effects on waist circumference and high-density lipoprotein levels. In addition, glucose level was significantly decreased in the subgroup of studies reporting change from baseline means, although the overall effect was not statistically significant (p = 0.81), while triglyceride levels were increased after the treatment period. In conclusion, the present meta-analysis evidenced the potential therapeutic effect of resveratrol on improving some MetS features, especially regarding systolic blood pressure, diastolic blood pressure, and glucose reduction; however, the results are still borderline and sometimes controversial, which might be justified by the methodological and statistical heterogeneity of the studies, with the latter varying from 17 to 57%.

The Impact of Curcumin, Resveratrol, and Cinnamon on Modulating Oxidative Stress and Antioxidant Activity in Type 2 Diabetes: Moving beyond an Anti-Hyperglycaemic Evaluation

Research indicates that up to half of the population resorts to dietary supplements for managing diseases such as type 2 diabetes rather than changing their nutritional habits. These supplements not only aim to have an anti-hyperglycaemic effect but also seek to reduce oxidative stress to prevent diabetes complications. This systematic literature systematic review aims to evaluate the efficacy of curcumin, resveratrol, and cinnamon in modulating oxidative stress and antioxidant activity in individuals with type 2 diabetes. Data were collected from PubMed, Web of Sciences, and Scopus databases regarding the impact of curcumin, resveratrol, and cinnamon on total antioxidant capacity (TAC), malondialdehyde (MDA), tumour necrosis factor α (TNF-α), interleukin 6 (IL-6), and high-sensitivity C-reactive protein (hs-CRP) levels for this review. Effect sizes for each study were calculated using Cohen's or Hedges's d coefficient. Parameters of oxidative stress and inflammatory status, such as TAC, MDA, TNF-α, IL-6, and hs-CRP, improved following phytochemicals. Additionally, curcumin, resveratrol, and cinnamon exhibited regulatory effects on carbohydrate metabolism by reducing glucose, insulin, and glycated haemoglobin concentrations and lipid metabolism by lowering total cholesterol (TC), low-density lipoprotein (LDL), and triglycerides (TG) and increasing high-density lipoprotein (HDL). Incorporating curcumin, resveratrol, and cinnamon into diets may be beneficial for maintaining organism homeostasis and improving metabolic control in individuals with type 2 diabetes. However, the conflicting results reported in the literature highlight the need for further detailed investigations into the effectiveness of phytochemical use for type 2 diabetes.

Increase in plasma resveratrol levels and in acid-resistant proteins in the acquired enamel pellicle after use of resveratrol-containing orodispersible tablets

OBJECTIVE

This study evaluated the effect of administration of trans-resveratrol-containing orodispersible tablets on the protein composition of the AEP and on blood plasma trans-resveratrol concentrations.

METHODS

Ten volunteers participated in two crossover double-blind phases. In each phase, after dental prophylaxis, they received a trans-resveratrol (15 mg) orodispersible tablet, or a placebo tablet (without actives). The AEP formed after 120 min was collected with electrode filter papers soaked in 3 % citric acid. Blood samples were collected 30, 45, 60 and 120 min after the use of the tablet. After protein extraction, AEP samples were analyzed by shotgun labelfree quantitative proteomics and plasma samples were analyzed by high-performance liquid chromatography (HPLC).

RESULTS

Eight hundred and two proteins were identified in the AEP. Among them, 336 and 213 were unique to the trans-resveratrol and control groups, respectively, while 253 were common to both groups. Proteins with important functions in the AEP had increased expression in the trans-resveratroltreated group, such as neutrophil defensins, S100 protein isoforms, lysozyme C, cystatin-D, mucin-7, alphaamylase, albumin, haptoglobin and statherin. Trans-resveratrol was detected in the plasma at all the times evaluated, with the peak at 30 min.

CONCLUSIONS

The administration of trans-resveratrol in sublingual orodispersible tablets was effective both to increase the bioavailability of the polyphenol and the expression of antibacterial and acid-resistant proteins in the AEP, which might benefit oral and general health.

Hypoglycemic effects and associated mechanisms of resveratrol and related stilbenes in diet

Hyperglycemia has become a global health problem due to changes in diet and lifestyle. Most importantly, persistent hyperglycemia can eventually develop into type II diabetes. While the usage of current drugs is limited by their side effects, stilbenes derived from fruits and herbal/dietary plants are considered as important phytochemicals with potential hypoglycemic properties. Herein, the most common stilbenoids in consumed foods, i.e. resveratrol, pterostilbene, piceatannol, oxyresveratrol, and 2,3,5,4'-tetrahydroxystilbene-2-O-β-glucopyranoside (THSG), are reviewed in this paper. These stilbenes are found to regulate glucose homeostasis via (a) modulation of feeding behaviour and nutrition absorption; (b) restoration of insulin signalling by enhancing insulin production/insulin sensitivity; (c) improvement of gut permeability, gut microbial profile and resulting metabolomes; and (d) amelioration of circadian rhythm disruption. In this review, we have summarized the underlying mechanisms for the hypoglycemic effects of the five most common dietary stilbenoids listed above, providing a comprehensive framework for future study and applications.

Resveratrol attenuates high glucose-induced inflammation and improves glucose metabolism in HepG2 cells

Diabetes mellitus (DM) is characterized by impaired glucose and insulin metabolism, resulting in chronic hyperglycemia. Hyperglycemia-induced inflammation is linked to the onset and progression of diabetes. Resveratrol (RES), a polyphenol phytoalexin, is studied in diabetes therapeutics research. This study evaluates the effect of RES on inflammation and glucose metabolism in HepG2 cells exposed to high glucose. Inflammation and glucose metabolism-related genes were investigated using qPCR. Further, inflammatory genes were analyzed by applying ELISA and Bioplex assays. High glucose significantly increases IKK-α, IKB-α, and NF-kB expression compared to controls. Increased NF-kB expression was followed by increased expression of pro-inflammatory cytokines, such as TNF-α, IL-6, IL-β, and COX2. RES treatment significantly reduced the expression of NF-kB, IKK-α, and IKB-α, as well as pro-inflammatory cytokines. High glucose levels reduced the expression of TGFβ1, while treatment with RES increased the expression of TGFβ1. As glucose levels increased, PEPCK expression was reduced, and GCK expression was increased in HepG2 cells treated with RES. Further, HepG2 cells cultured with high glucose showed significant increases in KLF7 and HIF1A but decreased SIRT1. Moreover, RES significantly increased SIRT1 expression and reduced KLF7 and HIF1A expression levels. Our results indicated that RES could attenuate high glucose-induced inflammation and enhance glucose metabolism in HepG2 cells.

Genetics and epigenetics of diabetes and its complications in India

Diabetes mellitus (DM) has become a significant health concern with an increasing rate of morbidity and mortality worldwide. India ranks second in the number of diabetes cases in the world. The increasing burden of DM can be explained by genetic predisposition of Indians to type 2 diabetes mellitus (T2DM) coupled with rapid urbanization and socio-economic development in the last 3 decades leading to drastic changes in lifestyle. Environment and lifestyle changes contribute to T2DM development by altering epigenetic processes such as DNA methylation, histone post-translational modifications, and long non-coding RNAs, all of which regulate chromatin structure and gene expression. Although the genetic predisposition of Indians to T2DM is well established, how environmental and genetic factors interact and lead to T2DM is not well understood. In this review, we discuss the prevalence of diabetes and its complications across different states in India and how various risk factors contribute to its pathogenesis. The review also highlights the role of genetic predisposition among the Indian population and epigenetic factors involved in the etiology of diabetes. Lastly, we review current treatments and emphasize the knowledge gap with respect to genetic and epigenetic factors in the Indian context. Further understanding of the genetic and epigenetic determinants will help in risk prediction and prevention as well as therapeutic interventions, which will improve the clinical management of diabetes and associated macro- and micro-vascular complications.

Recent progress in nanotechnology-based drug carriers for resveratrol delivery

Resveratrol is a polyphenol with diverse pharmacological activities, but its clinical efficacy is limited due to low solubility/permeability, light-induced isomerization, auto-oxidation, and rapid metabolism. Nanodelivery systems, such as liposomes, polymeric nanoparticles, lipid nanocarriers, micelles, nanocrystals, inorganic nanoparticles, nanoemulsions, protein-based nanoparticles, exosomes, macrophages, and red blood cells (RBCs) have shown great potential for improving the solubility, biocompatibility, and therapeutic efficacy of resveratrol. This review comprehensively summarizes the recent advances in resveratrol nanoencapsulation and describes potential strategies to improve the pharmacokinetics of existing nanoformulations, enhance targeting, reduce toxicity, and increase drug release and encapsulation efficiency. The article also suggests that in order to avoid potential safety issues, resveratrol nanoformulations must be tested in vivo in a wide range of diseases.

Natural Drugs: A New Direction for the Prevention and Treatment of Diabetes

Insulin resistance, as a common pathological process of many metabolic diseases, including diabetes and obesity, has attracted much attention due to its relevant influencing factors. To date, studies have mainly focused on the shared mechanisms between mitochondrial stress and insulin resistance, and they are now being pursued as a very attractive therapeutic target due to their extensive involvement in many human clinical settings. In view of the complex pathogenesis of diabetes, natural drugs have become new players in diabetes prevention and treatment because of their wide targets and few side effects. In particular, plant phenolics have received attention because of their close relationship with oxidative stress. In this review, we briefly review the mechanisms by which mitochondrial stress leads to insulin resistance. Moreover, we list some cytokines and genes that have recently been found to play roles in mitochondrial stress and insulin resistance. Furthermore, we describe several natural drugs that are currently widely used and give a brief overview of their therapeutic mechanisms. Finally, we suggest possible ideas for future research related to the unique role that natural drugs play in the treatment of insulin resistance through the above targets.

Interplay between Systemic Glycemia and Neuroprotective Activity of Resveratrol in Modulating Astrocyte SIRT1 Response to Neuroinflammation

The flow of substances between the blood and the central nervous system is precisely regulated by the blood-brain barrier (BBB). Its disruption due to unbalanced blood glucose levels (hyper- and hypoglycemia) occurring in metabolic disorders, such as type 2 diabetes, can lead to neuroinflammation, and increase the risk of developing neurodegenerative diseases. One of the most studied natural anti-diabetic, anti-inflammatory, and neuroprotective compounds is resveratrol (RSV). It activates sirtuin 1 (SIRT1), a key metabolism regulator dependent on cell energy status. The aim of this study was to assess the astrocyte SIRT1 response to neuroinflammation and subsequent RSV treatment, depending on systemic glycemia. For this purpose, we used an optimized in vitro model of the BBB consisting of endothelial cells and astrocytes, representing microvascular and brain compartments (MC and BC), in different glycemic backgrounds. Astrocyte-secreted SIRT1 reached the highest concentration in hypo-, the lowest in normo-, and the lowest in hyperglycemic backgrounds. Lipopolysaccharide (LPS)-induced neuroinflammation caused a substantial decrease in SIRT1 in all glycemic backgrounds, as observed earliest in hyperglycemia. RSV partially counterbalanced the effect of LPS on SIRT1 secretion, most remarkably in normoglycemia. Our results suggest that abnormal glycemic states have a worse prognosis for RSV-therapy effectiveness compared to normoglycemia.

Effect of resveratrol in gestational diabetes mellitus and its complications

The incidence rate of diabetes in pregnancy is about 20%, and diabetes in pregnancy will have a long-term impact on the metabolic health of mothers and their offspring. Mothers may have elevated blood glucose, which may lead to blood pressure disease, kidney disease, decreased resistance and secondary infection during pregnancy. The offspring may suffer from abnormal embryonic development, intrauterine growth restriction, obesity, autism, and other adverse consequences. Resveratrol (RSV) is a natural polyphenol compound, which is found in more than 70 plant species and their products, such as Polygonum cuspidatum, seeds of grapes, peanuts, blueberries, bilberries, and cranberries. Previous studies have shown that RSV has a potential beneficial effect on complex pregnancy, including improving the indicators of diabetes and pregnancy diabetes syndrome. This article has reviewed the molecular targets and signaling pathways of RSV, including AMP-activated protein kinase, mitogen-activated protein kinases, silent information regulator sirtuin 1, miR-23a-3p, reactive oxygen species, potassium channels and CX3C chemokine ligand 1, and the effect of RSV on gestational diabetes mellitus (GDM) and its complications. RSV improves the indicators of GDM by improving glucose metabolism and insulin tolerance, regulating blood lipids and plasma adipokines, and modulating embryonic oxidative stress and apoptosis. Furthermore, RSV can ameliorate the GDM complications by reducing oxidative stress, reducing the effects on placentation, reducing the adverse effects on embryonic development, reducing offspring's healthy risk, and so on. Thus, this review is of great significance for providing more options and possibilities for further research on medication of gestational diabetes.

Targeting Oxidative Stress with Polyphenols to Fight Liver Diseases

Reactive oxygen species (ROS) are important second messengers in many metabolic processes and signaling pathways. Disruption of the balance between ROS generation and antioxidant defenses results in the overproduction of ROS and subsequent oxidative damage to biomolecules and cellular components that disturb cellular function. Oxidative stress contributes to the initiation and progression of many liver pathologies such as ischemia-reperfusion injury (LIRI), non-alcoholic fatty liver disease (NAFLD), and hepatocellular carcinoma (HCC). Therefore, controlling ROS production is an attractive therapeutic strategy in relation to their treatment. In recent years, increasing evidence has supported the therapeutic effects of polyphenols on liver injury via the regulation of ROS levels. In the current review, we summarize the effects of polyphenols, such as quercetin, resveratrol, and curcumin, on oxidative damage during conditions that induce liver injury, such as LIRI, NAFLD, and HCC.

Resveratrol may mildly improve renal function in the general adult population: A systematic review and meta-analysis of randomized controlled clinical trials

Whether renal health biomarkers can benefit from resveratrol supplements is unknown. Thus, we conducted a systematic review and meta-analysis to summarize evidence from randomized controlled trials investigating the effect of resveratrol supplementation on renal health biomarkers. We hypothesized that resveratrol supplementation is associated with improved renal health biomarkers. Four electronic databases, including PubMed, Scopus, and Institute for Scientific Information Web of Science, and Cochrane Central, were searched for relevant articles up to February 2023. The pooled effect sizes were estimated using a random effects model and expressed as weighted mean difference (WMD) and 95% CI. In total, 32 articles were eligible for inclusion in the current meta-analysis. The pooled results indicated that resveratrol significantly decreased blood urea nitrogen (weighted mean difference [WMD]= -0.84 mg/dL; 95% CI, -1.48 to -0.20; P = .01; I² = 64.4%) and creatinine levels (WMD = -1.90 µmol/L; 95% CI, -3.59 to -0.21; P = .03; I²= 52.1%), and increased glomerular filtration rate (WMD = 7.58 mL/min/1.73 m²; 95% CI, 5.25-9.91; P < .001; I² = 0%). The favorable change of blood urea nitrogen was significant in studies with short follow-up duration (12 weeks or less), with lower doses of resveratrol (less than 500 mg/d), and those conducted in patients with diabetes. However, higher doses of resveratrol are needed to observe significant reductions in creatinine. No significant change was observed in albumin, total protein, and uric acid concentrations. This meta-analysis provides a low certainty of evidence indicating a mild renal protective effect of resveratrol in adults. Further high-quality evidence in patients with impaired renal function and estimates of mortality risk in these patients is required before resveratrol can be advocated as an adjuvant therapy.

Planting conditions can enhance the bioactivity of mulberry by affecting its composition

Mulberry (Morus alba L.) has a special significance in the history of agriculture and economic plant cultivation. Mulberry has strong environmental adaptability, a wide planting range, and abundant output. It is not only an important resource for silkworm breeding but also a raw ingredient for various foods and has great potential for the development of biological resources. The bioactivities of mulberry in different planting areas are not the same, which is an obstacle to the development of mulberry. This study collected information on the planting conditions of mulberry branches in 12 planting areas, such as altitude, temperature difference, and precipitation. A comparison of the levels of 12 constituents of mulberry branches from mulberry grown in different planting areas was then made. An in vitro model was used to study the bioactivities of mulberry branches in the 12 planting areas, and mathematical analysis was used to explain the possible reasons for the differences in the composition and bioactivities of mulberry branches in different planting areas. After studying mulberry samples from 12 planting areas in China, it was found that a small temperature difference could affect the antiapoptotic effect of mulberry branch on microvascular endothelial cells by changing the levels and proportions of rutin, hyperoside, and morusin. Adequate irrigation can promote the antioxidation of the mulberry branch on microvascular endothelial cells by changing the levels and proportions of scopoletin and quercitrin. The results of the analysis of planting conditions and the levels of active constituents and their correlation with bioactivities support the improvement of mulberry planting conditions and have great significance in the rational development of mulberry resources. This is the first time that a mathematical analysis method was used to analyze the effects of planting conditions on mulberry biological activity.

Insulin: A connection between pancreatic β cells and the hypothalamus

Insulin is a hormone secreted by pancreatic β cells. The concentration of glucose in circulation is proportional to the secretion of insulin by these cells. In target cells, insulin binds to its receptors and activates phosphatidylinositol-3-kinase/protein kinase B, inducing different mechanisms depending on the cell type. In the liver it activates the synthesis of glycogen, in adipose tissue and muscle it allows the capture of glucose, and in the hypothalamus, it regulates thermogenesis and appetite. Defects in insulin function [insulin resistance (IR)] are related to the development of neurodegenerative diseases in obese people. Furthermore, in obesity and diabetes, its role as an anorexigenic hormone in the hypothalamus is diminished during IR. Therefore, hyperphagia prevails, which aggravates hyper-glycemia and IR further, becoming a vicious circle in which the patient cannot regulate their need to eat. Uncontrolled calorie intake induces an increase in reactive oxygen species, overcoming cellular antioxidant defenses (oxidative stress). Reactive oxygen species activate stress-sensitive kinases, such as c-Jun N-terminal kinase and p38 mitogen-activated protein kinase, that induce phos-phorylation in serine residues in the insulin receptor, which blocks the insulin signaling pathway, continuing the mechanism of IR. The brain and pancreas are organs mainly affected by oxidative stress. The use of drugs that regulate food intake and improve glucose metabolism is the conventional therapy to improve the quality of life of these patients. Currently, the use of antioxidants that regulate oxidative stress has given good results because they reduce oxidative stress and inflammatory processes, and they also have fewer side effects than synthetic drugs.

Resveratrol Mitigates Diabetic Testicular Dysfunction, Endocrine Deficits, and Insulin Resistance via Suppression of Sperm-Endocrine Aberrations and Oxidative Inflammation in Rats

Diabetes mellitus (DM) provokes reproductive impairments through endocrine disturbance, sperm deficits, and testicular oxidative inflammation. The study investigated the reproductive protective effects of resveratrol (RSV) against testicular oxidative inflammation, sperm/endocrine deficits, and insulin resistance in streptozotocin- (STZ-, 65 mg/kg) induced DM rat model. Male rats were randomly divided into 4 groups ( $n=6$ ): control, DM, RSV (150 mg/kg bw, orally), and RSV+DM group (21 days). The nontreated DM rats showed marked decreases in serum insulin, reproductive hormones (T, LH, and FSH), and lipid profile levels compared to control. The homeostatic index of insulin resistance (HOMA-IR) and the quantitative insulin sensitivity check index (QUICKI) were adversely modulated. Sperm count and motility were profoundly decreased, whereas sperm abnormality was significantly increased. The testicular activities of catalase (CAT), glutathione peroxidase (GPx), superoxide dismutase (SOD), and malondialdehyde (MDA) level, along with inflammatory cytokines (TNF-α, IL-6, IL-4, and IL-10) were significantly dysregulated. The DM induced histopathological lesions compared to control rats. Interestingly, the RSV administration to DM rats attenuated the altered reproductive parameters, restored antioxidant mechanism, and anti-inflammatory responses with improved insulin resistance. RSV could prevent DM-induced reproductive deficits and insulin resistance via modulating oxidative stress-mediated testicular inflammation in rats.

The effect of resveratrol in cardio-metabolic disorders during pregnancy and offspring outcomes: a review

Resveratrol supplementation during pregnancy and lactation has been associated with a reduced risk of maternal obesity, gestational diabetes mellitus , and preeclampsia. In addition, emerging evidence has shown that maternal resveratrol supplementation diminishes cardio-metabolic disorders in offspring, highlighting its role in modulating adaptative responses involving phenotypical plasticity. Therefore, it is reasonable to infer that administration of resveratrol during pregnancy and lactation periods could be considered an important nutritional intervention to decrease the risk of maternal and offspring cardio-metabolic disorders. To highlight these new insights, this literature review will summarize the understanding emerging from experimental and clinical studies about resveratrol supplementation and its capacity to prevent or minimize maternal and offspring cardio-metabolic disorders.

Resveratrol, Endocrine Disrupting Chemicals, Neurodegenerative Diseases and Depression: Genes, Transcription Factors, microRNAs, and Sponges Involved

We aimed to examine the molecular basis of the positive effect of resveratrol against amyotrophic lateral sclerosis (ALS), Parkinson's disease (PD), cognitive impairment (CI), and depression induced by a mixture of bisphenol A (BPA), BPS, and BPF. The CTD, GeneMania, Metascape, SwissADME, Cytoscape, MIENTURNET, miRNAsong, and Autodock Vina were the fundamental tools for analysis. Resveratrol exerts its protective effects on selected diseases induced by a mixture of BPA, BPS, and BPF through the following genes: PTGS2 and GSR for ALS; INS, IL6, BDNF, and SOD1 for PD; BDNF, CASP3, TNF, INS, IGF1, IL1B for CI; and BDNF, PTGS2, and IL6 for depression. Detoxification was noted as the most important for ALS, dopamine metabolism for PD, apoptosis for CI, and the selenium micronutrient network for depression. hsa-miR-377-3p, hsa-miR-1-3p, hsa-miR-128-3p, and hsa-miR-204-5p were highlighted. We created and tested in silico sponges that inhibited these miRNAs. NFE2L2, BACH1, PPARG, and NR4A3 were listed as the key transcription factors implicated in resveratrol's protective effect against harmful studied chemicals. Furthermore, resveratrol's physicochemical properties and pharmacokinetics are consistent with its therapeutic benefits in ALS, PD, CI, and depression, owing to its high gastrointestinal absorption, drug-likeness, non-P-glycoprotein substrate, and capacity to penetrate the blood-brain barrier.

The role of dietary antioxidants in type 2 diabetes and neurodegenerative disorders: An assessment of the benefit profile

Healthy diet is vital to cellular health. The human body succumbs to numerous diseases which afflict severe economic and psychological burdens on the patient and family. Oxidative stress is a possible crucial regulator of various pathologies, including type 2 diabetes and neurodegenerative diseases. It generates reactive oxygen species (ROS) that trigger the dysregulation of essential cellular functions, ultimately affecting cellular health and homeostasis. However, lower levels of ROS can be advantageous and are implicated in a variety of signaling pathways. Due to this dichotomy, the terms oxidative "eustress," which refers to a good oxidative event, and "distress," which can be hazardous, have developed. ROS affects multiple signaling pathways, leading to compromised insulin secretion, insulin resistance, and β-cell dysfunction in diabetes. ROS is also associated with increased mitochondrial dysfunction and neuroinflammation, aggravating neurodegenerative conditions in the body, particularly with age. Treatment includes drugs/therapies often associated with dependence, side effects including non-selectivity, and possible toxicity, particularly in the long run. It is imperative to explore alternative medicines as an adjunct therapy, utilizing natural remedies/resources to avoid all the possible harms. Antioxidants are vital components of our body that fight disease by reducing oxidative stress or nullifying the excess toxic free radicals produced under various pathological conditions. In this review, we focus on the antioxidant effects of components of dietary foods such as tea, coffee, wine, oils, and honey and the role and mechanism of action of these antioxidants in alleviating type 2 diabetes and neurodegenerative disorders. We aim to provide information about possible alternatives to drug treatments used alone or combined to reduce drug intake and encourage the consumption of natural ingredients at doses adequate to promote health and combat pathologies while reducing unwanted risks and side effects.

Profiling of insulin and resveratrol interaction using multi-spectroscopy and molecular docking study

Background

Resveratrol, a phenolic compound, has various medicinal properties, including anticancer, anti-diabetic, antioxidant, anti-inflammatory, etc. Diabetes is a killing disease, especially for people who cannot maintain a healthy lifestyle. People with diabetes need additional information about a supplement that can prevent and treat diabetes. The present study aims to investigate the interaction of insulin with resveratrol using fluorescence spectroscopy, UV–Vis spectroscopy, CD spectropolarimeter, and molecular docking methods. As an outcome of this study, we expect to understand the contribution of resveratrol in insulin resistance.

Result

The fluorescence spectroscopy results showed that the peak intensity of insulin emission decreased with resveratrol. The interaction of insulin with resveratrol involved a combination of static and dynamic quenching effects. Temperature changes caused the binding constant (K) and the binding site (n) unstable. The interaction occurred through hydrogen bonding, van der Waal, and was hydrophobic. The results of UV–Vis spectroscopy showed that the addition of resveratrol caused a peak in a blueshift, and the absorbance was hyperchromic. Also, there was a reduction in electron transition and the extinction coefficient. The CD spectropolarimeter results showed that the addition of resveratrol affected the secondary structure of insulin. The amount of α-helix and β-sheet slightly change and increase in the secondary structure’s length. The molecular docking study showed that resveratrol interacts via hydrogen bonding with glycine and asparagine. van der Waal interactions occurred in asparagine, phenylalanine, and cysteine. The interaction of electrons occurred through the π orbitals of resveratrol with tyrosine A and B. The binding energy of molecules interaction happened spontaneously on a hydrophobic surface.

Conclusion

Profiling the interaction of insulin and resveratrol shows that resveratrol can stabilize insulin structure and prevent insulin resistance in diabetes.

Phenolic Compounds Known to Be Present in Lingonberry (Vaccinium vitis-idaea L.) Enhance Macrophage Polarization towards the Anti-Inflammatory M2 Phenotype

Macrophages are pleiotropic immune cells whose phenotype can polarize towards the pro-inflammatory M1 or anti-inflammatory M2 direction as a response to environmental changes. In obesity, the number of macrophages in adipose tissue is enhanced, and they shift towards the M1 phenotype. Activated M1 macrophages secrete pro-inflammatory cytokines and adipokines involved in the development of systemic low-grade inflammation, complicating obesity. Polyphenols are widely found in the vegetable kingdom and have anti-inflammatory properties. We and others have recently found that lingonberry (Vaccinium vitis-idaea L.) supplementation is able to prevent the development of low-grade inflammation and its metabolic consequences in experimentally induced obesity. In the present study, we investigated the effects of twelve phenolic compounds known to be present in lingonberry (resveratrol, piceid, quercetin, kaempferol, proanthocyanidins, delphinidin, cyanidin, benzoic acid, cinnamic acid, coumaric acid, caffeic acid, and ferulic acid) on macrophage polarization, which is a meaningful mechanism determining the low-grade inflammation in obesity. Mouse J774 and human U937 macrophages and commercially available phenolic compounds were used in the studies. Three of the twelve compounds investigated showed an effect on macrophage polarization. Resveratrol, kaempferol, and proanthocyanidins enhanced anti-inflammatory M2-type activation, evidenced as increased expression of Arg-1 and MRC-1 in murine macrophages and CCL-17 and MRC-1 in human macrophages. Resveratrol and kaempferol also inhibited pro-inflammatory M1-type activation, shown as decreased expression of IL-6, NO, and MCP-1 in murine macrophages and TNF-α and IL-6 in human macrophages. In the further mechanistic studies, the effects of the three active compounds were investigated on two transcription factors important in M2 activation, namely on PPARγ and STAT6. Resveratrol and kaempferol were found to enhance PPARγ expression, while proanthocyanidins increased the phosphorylation of STAT6. The results suggest proanthocyanidins, resveratrol, and kaempferol as active constituents that may be responsible for the positive anti-inflammatory effects of lingonberry supplementation in obesity models. These data also extend the previous knowledge on the anti-inflammatory effects of lingonberry and encourage further studies to support the use of lingonberry and lingonberry-based products as a part of a healthy diet.

Effects of Fruit and Vegetable Polyphenols on the Glycemic Control and Metabolic Parameters in Type 2 Diabetes Mellitus: A Review

The high prevalence of diabetes in recent decades has been associated with lifestyle changes and dietary habits correlated with economic development. Fruits and vegetables are a vital source of nutraceuticals and components of the healthy diet recommended in the medical nutrition therapy for type 2 diabetes mellitus (T2DM) to prevent hyperglycemia and related complications. They are low in calories and rich in dietary fiber, consist of many polyphenols, and are an essential component of a healthy lifestyle. Recently, researchers have developed a significant interest in understanding the effects of polyphenols (flavonoids and non-flavonoids) on blood glucose levels. In this review, the authors summarize the effects of polyphenols commonly found in the fruits and vegetables, such as resveratrol and anthocyanins, on the glycemic control and metabolic parameters, based on human clinical trials. Significant reductions in fasting blood glucose, glycated hemoglobin, and low-density lipoprotein cholesterol levels were reported after resveratrol, anthocyanin, and naringin were administered to patients with prediabetes and diabetes. Decreased insulin levels were observed after resveratrol intervention but not with the other types of polyphenols. These effects of polyphenolic compounds on the glycemic and metabolic parameters might be mediated by multiple pathophysiological mechanisms, such as activating regulator proteins to increase insulin signaling and eventually suppress insulin resistance. The benefits of certain polyphenols on T2DM remain ambiguous; therefore, further studies, especially clinical trials, are required to substantiate the available evidence.

Influence of Age and Dose on the Effect of Resveratrol for Glycemic Control in Type 2 Diabetes Mellitus: Systematic Review and Meta-Analysis

Background: Several clinical trials have suggested that resveratrol has hypoglycemic properties; however, there are other studies in which such an effect has not been observed. Methods: We carried out a systematic search in several databases; seventeen studies were selected for the systematic review and fifteen were included in the meta-analysis. Results: Resveratrol decreases glucose levels in subjects aged 45−59 years at doses <250 mg/day (−8.64 mg/dL, p < 0.00001), 250−500 mg/day (−22.24 mg/dL, p = 0.0003), and 500−1000 mg/day (−28.40 mg/dL, p = 0.0008), while in subjects older than 60 years, it only decreases with doses of 250−500 mg/day. Likewise, HbA1c improved in subjects aged 45−59 years with doses of 250−500 mg (−0.60%, p < 0.00001), but not in subjects older than 60 years. Insulin levels improved in subjects aged 45−59 years with doses < 250 mg/day (−0.80 mIU/L, p = 0.0003) and doses of 250−500 mg/day (−5.0 mIU/L, p = 0.0003), although in subjects older than 60 years, they only improved with doses of 250−500 mg/day (−1.79 mIU/L, p = 0.01). On the other hand, HOMA-IR only improved in subjects older than 60 years with doses of 250−500 mg/day (−0.40, p = 0.01). Conclusions: Resveratrol has a statistically significant dose−response effect on glucose concentrations, HbA1c, and insulin levels; however, there is not enough scientific evidence to propose a therapeutic dose.

Herbal medications and natural products for patients with covid-19 and diabetes mellitus: Potentials and challenges

BACKGROUND

The presence of diabetes mellitus (DM) among COVID-19 patients is associated with increased hospitalization, morbidity, and mortality. Evidence has shown that hyperglycemia potentiates SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) infection and plays a central role in severe COVID-19 and diabetes comorbidity. In this review, we explore the therapeutic potentials of herbal medications and natural products in the management of COVID-19 and DM comorbidity and the challenges associated with the preexisting or concurrent use of these substances.

METHODS

Research papers that were published from January 2016 to December 2021 were retrieved from PubMed, ScienceDirect, and Google Scholar databases. Papers reporting clinical evidence of antidiabetic activities and any available evidence of the anti-COVID-19 potential of ten selected natural products were retrieved and analyzed for discussion in this review.

RESULTS

A total of 548 papers (73 clinical trials on the antidiabetic activities of the selected natural products and 475 research and review articles on their anti-COVID-19 potential) were retrieved from the literature search for further analysis. A total of 517 articles (reviews and less relevant research papers) were excluded. A cumulative sum of thirty-one (31) research papers (20 clinical trials and 10 others) met the criteria and have been discussed in this review.

CONCLUSION

The findings of this review suggest that phenolic compounds are the most promising phytochemicals in the management of COVID-19 and DM comorbidity. Curcumin and propolis have shown substantial evidence against COVID-19 and DM in humans and are thus, considered the best potential therapeutic options.

Effect of resveratrol administration on ovarian morphology, determined by transvaginal ultrasound for the women with polycystic ovary syndrome (PCOS)

Intake of resveratrol has been associated with improved ovarian morphology under in vitro and in the animal models; however, this finding has not been confirmed in trials. The aim of our study was, therefore, to use a placebo-controlled approach with the detailed assessment of the ovarian morphology by applying transvaginal ultrasound to examine the effectiveness of this therapeutic approach in this group of women. The mean age of all participants was 28·61 (sd 4·99) years, with the mean BMI of 28·26 (sd 5·62) kg/m2. Resveratrol therapy, as compared with placebo, was associated with a significantly higher rate of improvement in the ovarian morphology (P = 0·02). Women who received resveratrol had a more dominant follicle than those getting placebo, with a significant reduction in the ovarian volume (P < 0·05). However, the number of follicle count per ovary (FNPO), stromal area (SA), ovarian echogenicity and distribution of follicles were not significantly altered (P > 0·05). Forty-one women with polycystic ovary syndrome (PCOS) were randomly assigned (1:1) to 3 months of daily 1000 mg resveratrol or placebo. Random assignment was done by blocked randomisation. Our primary endpoints were the change in the ovarian volume, SA and antral FNPO from the baseline to 3 months. Secondary endpoints were improvement in the distribution of follicles and ovarian echogenicity. Differences between the resveratrol and control groups were evaluated by Chi-square, Fisher's exact test and repeated-measures ANOVA. Treatment with resveratrol significantly reduced the ovarian volume and polycystic ovarian morphology, thus suggesting a disease-modifying effect in PCOS.

Investigating Polyphenol Nanoformulations for Therapeutic Targets against Diabetes Mellitus

Diabetes mellitus (DM) is a fatal metabolic disorder, and its prevalence has escalated in recent decades to a greater extent. Since the incidence and severity of the disease are constantly increasing, plenty of therapeutic approaches are being considered as a promising solution. Many dietary polyphenols have been reported to be effective against diabetes along with its accompanying vascular consequences by targeting multiple therapeutic targets. Additionally, the biocompatibility of these polyphenols raises questions about their use as pharmacological mediators. Nevertheless, the pharmacokinetic and biopharmaceutical properties of these polyphenols limit their clinical benefit as therapeutics. Pharmaceutical industries have attempted to improve compliance and therapeutic effects. However, nanotechnological approaches to overcome the pharmacokinetic and biopharmaceutical barriers associated with polyphenols as antidiabetic medications have been shown to be effective to improve clinical compliance and efficacy. Therefore, this review highlighted a comprehensive and up-to-date assessment of polyphenol nanoformulations in the treatment of diabetes and vascular consequences.

Implications of Resveratrol in Obesity and Insulin Resistance: A State-of-the-Art Review

Background: Resveratrol is a polyphenol chemical that naturally occurs in many plant-based dietary products, most notably, red wine. Discovered in 1939, widespread interest in the potential health benefits of resveratrol emerged in the 1970s in response to epidemiological data on the cardioprotective effects of wine. Objective: To explore the background of resveratrol (including its origins, stability, and metabolism), the metabolic effects of resveratrol and its mechanisms of action, and a potential future role of dietary resveratrol in the lifestyle management of obesity. Data sources: We performed a narrative review, based on relevant articles written in English from a Pubmed search, using the following search terms: “resveratrol”, “obesity”, “Diabetes Mellitus”, and “insulin sensitivity”. Results: Following its ingestion, resveratrol undergoes extensive metabolism. This includes conjugation (with sulfate and glucuronate) within enterocytes, hydrolyzation and reduction within the gut through the action of the microbiota (with the formation of metabolites such as dihydroresveratrol), and enterohepatic circulation via the bile. Ex vivo studies on adipose tissue reveal that resveratrol inhibits adipogenesis and prevents the accumulation of triglycerides through effects on the expression of Peroxisome Proliferator-activated Receptor γ (PPARγ) and sirtuin 1, respectively. Furthermore, resveratrol induces anti-inflammatory effects, supported by data from animal-based studies. Limited data from human-based studies reveal that resveratrol improves insulin sensitivity and fasting glucose levels in patients with Type 2 Diabetes Mellitus and may improve inflammatory status in human obesity. Although numerous mechanisms may underlie the metabolic benefits of resveratrol, evidence supports a role in its interaction with the gut microbiota and modulation of protein targets, including sirtuins and proteins related to nitric oxide, insulin, and nuclear hormone receptors (such as PPARγ). Conclusions: Despite much interest, there remain important unanswered questions regarding its optimal dosage (and how this may differ between and within individuals), and possible benefits within the general population, including the potential for weight-loss and improved metabolic function. Future studies should properly address these important questions before we can advocate the widespread adoption of dietary resveratrol supplementation.

Resveratrol attenuates behavioural impairment associated with learning and memory in HFD-STZ induced diabetic rats

BACKGROUND AND PURPOSE

Literature have indicated that a high-fat diet (HFD) is a common risk factor for type 2 diabetes mellitus (T2DM) and its associated cognitive-impairments. Mounting evidence supports that, in the diabetic animal model, resveratrol (RSV, SIRT1-modulator) can regulate the fasting glucose and antioxidant levels, as well as the lipid profile, and may alleviate the cognitive-dysfunction associated with diabetes.

EXPERIMENTAL APPROACH

Albino rats were fed 60% HFD-STZ (45mg/kg,i.p, single dose) to induce T2DM so that the experimental T2DM animal model could be used. After 14 weeks of the animals being in a confirmed diabetic condition, they were divided into various groups and treated with metformin(200mg/kg,i.p.) and RSV(50 and 100 mg/kg,i.p.) for four weeks. A multimodal approach involving oxidative-nitroso-stress, SIRT1, TGF-β1 levels, inflammation, cholinergic activity (serum, hippocampus, cerebral cortex), and a battery of behavioural studies associated with learning-memory were performed during and after the experimental-protocol.

KEY RESULTS

The administration of RSV significantly attenuated the increased glucose levels (pre, and post-prandial), impaired glucose tolerance, HbA1c, and decreased the body weights of the T2DM rats. Moreover, RSV ameliorated the impaired learning and memory-associated with increased SIRT1 and the decreased TGF-β1, TNF-α, oxidative-nitroso-stress and cholinergic activities in the serum and the brains of the T2DM-animals.

CONCLUSION AND IMPLICATION

Our investigations demonstrate that SIRT1-modulation can inter-play with TGF-β1 signalling, as well as mitigate hyperglycaemia and subsequent learning-memory impairments, in the T2DM-animals. Moreover, our study showed that novel therapeutic-targets, including TGF-β1, may add to our knowledge of RSV when used in the treatment of impaired memory-associated with diabetes.

The Invasive Species Reynoutria japonica Houtt. as a Promising Natural Agent for Cardiovascular and Digestive System Illness

Polygoni Cuspidati Rhizoma et Radix, the dry roots and stems of Reynoutria japonica Houtt (called Huzhang, HZ in Chinese), is a traditional and popular chinese medicinal herb for thousands of years. As a widely used ethnomedicine in Asia including China, Japan, and Korea, HZ can invigorate the blood, cool heat, and resolve toxicity, which is commonly used in the treatment of favus, jaundice, scald, and constipation. However, HZ is now considered an invasive plant in the United States and many European countries. Therefore, in order to take advantage of HZ and solve the problem of biological invasion, scholars around the world have carried out abundant research studies on HZ. Until now, about 110 compounds have been isolated and identified from HZ, in which anthraquinones, stilbenes, and flavonoids would be the main bioactive ingredients for its pharmacological properties, such as microcirculation improvement, myocardial protective effects, endocrine regulation, anti-atherosclerotic activity, anti-oxidant activity, anti-tumor activity, anti-viral activity, and treatment of skin inflammation, burns, and scalds. HZ has a variety of active ingredients and broad pharmacological activities. It is widely used in health products, cosmetics, and even animal husbandry feed and has no obvious toxicity. Efforts should be made to develop more products such as effective drugs, health care products, cosmetics, and agricultural and animal husbandry products to benefit mankind.

Resveratrol in Treating Diabetes and Its Cardiovascular Complications: A Review of Its Mechanisms of Action

Diabetes mellitus (DM) is one of the most prevalent chronic diseases worldwide. High morbidity and mortality caused by DM are closely linked to its complications in multiple organs/tissues, including cardiovascular complications, diabetic nephropathy, and diabetic neuropathy. Resveratrol is a plant-derived polyphenolic compound with pleiotropic protective effects, ranging from antioxidant and anti-inflammatory to hypoglycemic effects. Recent studies strongly suggest that the consumption of resveratrol offers protection against diabetes and its cardiovascular complications. The protective effects of resveratrol involve the regulation of multiple signaling pathways, including inhibition of oxidative stress and inflammation, enhancement of insulin sensitivity, induction of autophagy, regulation of lipid metabolism, promotion of GLUT4 expression, and translocation, and activation of SIRT1/AMPK signaling axis. The cardiovascular protective effects of resveratrol have been recently reviewed in the literature, but the role of resveratrol in preventing diabetes mellitus and its cardiovascular complications has not been systematically reviewed. Therefore, in this review, we summarize the pharmacological effects and mechanisms of action of resveratrol based on in vitro and in vivo studies, highlighting the therapeutic potential of resveratrol in the prevention and treatment of diabetes and its cardiovascular complications.

Polyphenol Supplementation Did Not Affect Insulin Sensitivity and Fat Deposition During One-Month Overfeeding in Randomized Placebo-Controlled Trials in Men and in Women

Two randomized placebo-controlled double-blind paralleled trials (42 men in Lyon, 19 women in Lausanne) were designed to test 2 g/day of a grape polyphenol extract during 31 days of high calorie-high fructose overfeeding. Hyperinsulinemic-euglycemic clamps and test meals with [1,1,1-¹³C₃]-triolein were performed before and at the end of the intervention. Changes in body composition were assessed by dual-energy X-ray absorptiometry (DEXA). Fat volumes of the abdominal region and liver fat content were determined in men only, using 3D-magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) at 3T. Adipocyte's size was measured in subcutaneous fat biopsies. Bodyweight and fat mass increased during overfeeding, in men and in women. While whole body insulin sensitivity did not change, homeostasis model assessment of insulin resistance (HOMA-IR) and the hepatic insulin resistance index (HIR) increased during overfeeding. Liver fat increased in men. However, grape polyphenol supplementation did not modify the metabolic and anthropometric parameters or counteract the changes during overfeeding, neither in men nor in women. Polyphenol intake was associated with a reduction in adipocyte size in women femoral fat. Grape polyphenol supplementation did not counteract the moderated metabolic alterations induced by one month of high calorie-high fructose overfeeding in men and women. The clinical trials are registered under the numbers NCT02145780 and NCT02225457 at ClinicalTrials.gov and available at https://clinicaltrials.gov/ct2/show/NCT02145780 and https://clinicaltrials.gov/ct2/show/NCT02225457.

3,3′,4,5′-Tetramethoxy-trans-stilbene Improves Insulin Resistance by Activating the IRS/PI3K/Akt Pathway and Inhibiting Oxidative Stress

The potential anti-diabetic effect of resveratrol derivative, 3,3′,4,5′-tetramethoxy-trans-stilbene (3,3′,4,5′-TMS) and its underlying mechanism in high glucose (HG) and dexamethasone (DXMS)-stimulated insulin-resistant HepG2 cells (IR-HepG2) were investigated. 3,3′,4,5′-TMS did not reduce the cell viability of IR-HepG2 cells at the concentrations of 0.5–10 µM. 3,3′,4,5′-TMS increased the potential of glucose consumption and glycogen synthesis in a concentration-dependent manner in IR-HepG2 cells. 3,3′,4,5′-TMS ameliorated insulin resistance by enhancing the phosphorylation of glycogen synthase kinase 3 beta (GSK3β), inhibiting phosphorylation of insulin receptor substrate-1 (IRS-1), and activating phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) pathway in IR-HepG2 cells. Furthermore, 3,3′,4,5′-TMS significantly suppressed levels of reactive oxygen species (ROS) with up-regulation of nuclear factor erythroid 2-related factor 2 (Nrf2) expression. To conclude, the beneficial effect of 3,3′,4,5′-TMS against insulin resistance to increase glucose consumption and glycogen synthesis was mediated through activation of IRS/PI3K/Akt signaling pathways in the IR-HepG2 cells, accomplished with anti-oxidative activity through up-regulation of Nrf2.

Effect of resveratrol supplementation on hepatic steatosis and cardiovascular indices in overweight subjects with type 2 diabetes: a double-blind, randomized controlled trial

BACKGROUND

Patients with type 2 diabetes mellitus (T2DM) are prone to develop non-alcoholic fatty liver disease (NAFLD) and cardiovascular diseases (CVD). We aimed to investigate whether the resveratrol supplementation improves novel hepatic and cardiovascular indices in these patients.

METHODS

We conducted a double-blind, randomized controlled trial for 8 weeks. Seventy-six patients with T2DM were randomly assigned to receive 1000 mg/day resveratrol or placebo. Levels of lipid accumulation product (LAP), visceral adiposity index (VAI), Castelli risk index I (CRI-I), CRI-II and atherogenic coefficient (AC) were measured at the beginning and after intervention.

RESULTS

A total of 71 participants completed the trial. After adjusting for confounding factors including medications, diabetes duration, energy intake and physical activity, no significant difference was found between the intervention group and the control group in LAP (mean change: - 2.46 ± 23.3 vs. 1.43 ± 14.3; P = 0.43), VAI (mean change: - 0.25 ± 1.1 vs. - 0.02 ± 0.6; P = 0.47), CRI-I (mean change: - 0.25 ± 0.9 vs. - 0.09 ± 0.5; P = 0.79), CRI-II (mean change: - 0.23 ± 0.7 vs. - 0.06 ± 0.6; P = 0.38) and AC (mean change: - 0.25 ± 0.9 vs. - 0.09 ± 0.5; P = 0.79).

CONCLUSIONS

Resveratrol supplementation had no effect on hepatic steatosis and cardiovascular indices. Further clinical trials, especially among subjects with dyslipidemia are needed to reach a firm conclusion. In addition, taking all medications should be controlled in future studies. Trial registration The protocol was registered on 29/12/2017 at the Iranian clinical trials website (IRCT20171118037528N1) with URL: https://en.irct.ir/trial/27734 .

Resveratrol Inhibits Metabolism and Affects Blood Platelet Function in Type 2 Diabetes

Chronic hyperglycemia contributes to vascular complications in diabetes. Resveratrol exerts anti-diabetic and anti-platelet action. This study aimed to evaluate the effects of resveratrol on metabolism and the function of blood platelets under static and in in vitro flow conditions in patients with type 2 diabetes. Blood obtained from 8 healthy volunteers and 10 patients with type 2 diabetes was incubated with resveratrol and perfused over collagen-coated capillaries. Isolated blood platelets were incubated with resveratrol and activated by collagen to assess platelet function, metabolism, ATP release, TXA₂ production, lipid peroxidation, and gluthatione content. In the type 2 diabetes group, plasma glucose and fructosamine concentrations were significantly higher than in the healthy group. In in vitro studies, collagen-induced thrombi formation in the blood of diabetic patients was 33% higher than in the healthy group. Resveratrol reduced thrombi by over 50% in the blood of healthy and diabetic patients. TXA₂ production was 47% higher in diabetic platelets than in the healthy group. Resveratrol reduced TXA₂ release by 38% in healthy platelets and by 79% in diabetic platelets. Resveratrol also reduced the activities of enzymes responsible for glycolysis and oxidative metabolism in the platelets of both groups. These data indicate that the resveratrol-induced inhibition of platelet metabolism and TXA₂ release may lead to a reduction of platelet function and thrombus formation in patients with type 2 diabetes. Therefore, resveratrol may be beneficial to prevent vascular complications as a future complementary treatment in aspirin-resistant diabetic patients.

Role of resveratrol supplementation in regulation of glucose hemostasis, inflammation and oxidative stress in patients with diabetes mellitus type 2: A randomized, placebo-controlled trial

OBJECTIVE

The objective was to determine the effects of resveratrol supplementation on glucose homeostasis, oxidative stress, inflammation and microRNAs expression in patients with diabetes mellitus type 2 on oral hypoglycemic drugs.

METHOD

This was a randomized, double blinded placebo-controlled parallel group trial. The diabetic patients (n=110) were randomly assigned either to resveratrol (n=55) and placebo (55) groups after informed consent and given once daily resveratrol 200mg and cellulose capsules respectively for 24 weeks. Fasting glucose, insulin, HbA1c, lipid profile, TNF- α, IL-6, hs-CRP, MDA & circulatory microRNAs were measured at start and end of 24- week intervention.

RESULTS

Out of 110 patients recruited, 94 patients completed the study comprising of 45 in resveratrol and 46 in placebo group. The resveratrol supplementation after 24 weeks was resulted in significant reduction [mean difference (95%CI)] of plasma glucose[-0.50(-0.94 to -0.06)], insulin[-1.31(-2.24 to -0.38)], homeostatic model assessment of insulin resistance[-0.83(-1.37 to -0.29)], malondialdehyde[-0.36(-0.61 to -0.11)], high sensitive-C-reactive protein[-0.35(-0.70 to -0.01)], tumor necrosis factor-alpha[-1.25(-1.90 to -0.61)] and interleukin-6[-1.99(-3.29 to -0.69)]. More than two-fold down regulation in miRNA-34a, miRNA-375, miRNA-21, miRNA-192 and up regulation in miRNA-126 and miRNA-132 expression was noted in patients receiving resveratrol as compared to placebo. No side effects were reported during the trial.

CONCLUSION

Resveratrol supplementation contributes in improvement of glycemic control by reducing insulin resistance. It has significant beneficial impact on chronic inflammation, oxidative stress and associated microRNA expression in diabetic patients. Thus, supplementation of resveratrol along with oral hypoglycemic agents may be useful in the reduction of diabetic associated complications.

The Cost-Effectiveness of Supplemental Carnosine in Type 2 Diabetes

In this paper, we assess the cost-effectiveness of 1 g daily of carnosine (an over the counter supplement) in addition to standard care for the management of type 2 diabetes and compare it to standard care alone. Dynamic multistate life table models were constructed in order to estimate both clinical outcomes and costs of Australians aged 18 years and above with and without type 2 diabetes over a ten-year period, 2020 to 2029. The dynamic nature of the model allowed for population change over time (migration and deaths) and accounted for the development of new cases of diabetes. The three health states were 'Alive without type 2 diabetes', 'Alive with type 2 diabetes' and 'Dead'. Transition probabilities, costs, and utilities were obtained from published sources. The main outcome of interest was the incremental cost-effectiveness ratio (ICER) in terms of cost per year of life saved (YoLS) and cost per quality-adjusted life year (QALY) gained. Over the ten-year period, the addition of carnosine to standard care treatment resulted in ICERs (discounted) of AUD 34,836 per YoLS and AUD 43,270 per QALY gained. Assuming the commonly accepted willingness to pay threshold of AUD 50,000 per QALY gained, supplemental dietary carnosine may be a cost-effective treatment option for people with type 2 diabetes in Australia.

Maternal resveratrol supplementation ameliorates bisphenol A-induced atherosclerotic lesions formation in adult offspring ApoE-/- mice

Current evidence suggests that intrauterine bisphenol A (BPA) exposure increases the risk of developing cardiovascular diseases in later stages of life. The beneficial effect of resveratrol (Rsv) on developmental programming of atherosclerosis lesions formation in offspring is seldom reported. Hence, we sought to study the effect of maternal Rsv in ameliorating perinatal BPA exposure-induced atherosclerosis lesions formation in adult offspring using the apolipoprotein E-deficient (ApoE^-/-) mice model. The pregnant ApoE^-/- mice were allocated into three groups: control, BPA, BPA + resveratrol (BPA + Rsv). The BPA group mice received BPA in their drinking water (1 μg/ml). BPA + Rsv group mice received BPA in their drinking water (1 μg/ml) and were treated orally with Rsv (20 mg kg^-1 day^-1). All the treatments were continued throughout the gestation and lactation period. Quantitative analysis of Sudan IV-stained aorta revealed a significantly increased area of atherosclerotic lesions in both female (p < 0.01) and male adult offspring mice (p < 0.01) in the BPA group. Supplementation with Rsv significantly reduced the BPA-induced atherosclerotic lesion development in the female offspring mice (p < 0.05). Transmission electron microscopy revealed the presence of a significantly high incidence of autophagic endothelial, smooth muscle, and macrophage cells in the aorta of BPA-exposed mice. Rsv treatment reduced the incidence of autophagic cells in BPA-exposed mice. In conclusion, maternal Rsv supplementation significantly prevents the BPA-induced atherosclerotic lesions formation in a sex-dependent manner potentially by acting as an autophagy modulator.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s13205-021-03078-y.

The effects of resveratrol supplementation in patients with type 2 diabetes, metabolic syndrome, and nonalcoholic fatty liver disease: an umbrella review of meta-analyses of randomized controlled trials

BACKGROUND

Uncertainty remains about the estimates of the effects for resveratrol supplementation, including the certainty of the evidence for each estimate and the magnitude of the observed impact based on the minimal important difference.

OBJECTIVE

We aimed to provide an overview of the effects of resveratrol supplementation, in comparison to control groups, for the management of cardiometabolic risk factors in patients with type 2 diabetes (T2D), metabolic syndrome (MetS), and nonalcoholic fatty liver disease (NAFLD).

METHODS

PubMed, Scopus, and ISI Web of Science were searched from inception to May 2021. For each meta-analysis, the mean difference and its 95% CI were recalculated using a random-effects model. The certainty of evidence was rated using the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) approach.

RESULTS

We identified 11 meta-analyses corresponding to 29 outcomes in 1476 individuals with T2D, 17 meta-analyses reporting 26 outcomes in 727 participants with the MetS, and 10 meta-analyses reporting 24 outcomes in 271 patients with NAFLD. Resveratrol supplementation had beneficial effects on some outcomes such as blood pressure, lipid profile, glycemic control, and insulin resistance in T2D, waist circumference in MetS, and body-weight and inflammation markers in NAFLD; however, for almost all outcomes, the magnitude of the effect was trivial, the certainty of evidence was very low to low, or the number of trials was too few. In the case of glycated hemoglobin (HbA1c), there was evidence that resveratrol can exert favorable and clinically important effects in the short term (<12 wk; mean difference: -1.05%, 95% CI: -2.09%, -0.02%; n = 6; GRADE = moderate).

CONCLUSIONS

Current evidence does not support supplementation with resveratrol for the management of cardiometabolic risk factors in patients with T2D, MetS, and NAFLD. In the case of HbA1c, subject to the limitations such as short-term follow-up and small sample size, there was a clinically important effect. The protocol of the present systematic review was registered in Open Science Framework (https://osf.io/ake85; registration doi: 10.17605/OSF.IO/AKE85).

The effects of resveratrol on glycemic control and cardiometabolic parameters in patients with T2DM: A systematic review and meta-analysis

BACKGROUND

Type 2 diabetes mellitus (T2DM) is a progressive meta-inflammatory disorder, which induce micro and macrovascular complications. Resveratrol is a nutraceutical known to have antioxidant and anti-inflammatory properties. It improves insulin resistance; however, no clear evidence regarding its effects in patients with T2DM.

OBJECTIVES

We aimed to evaluate the efficacy and the safety of oral resveratrol supplementation in type 2 diabetic patients concerning dose and duration.

METHODS

We searched PubMed, Cochrane Library, Scopus, WOS, Wiley, and Google Scholar for RCTs evaluating the efficacy and safety of resveratrol on patients with T2DM. We screened the studies for the eligibility criteria, performed the quality assessment, extracted the studies' characteristics, baseline, and outcome data of interest, and finally conducted the meta-analysis using RevManV5.3.

RESULTS

This systematic review and meta-analysis, including 17 RCTs with total 871 patients with T2DM, showed that resveratrol was superior to placebo on fasting blood glucose (FBG) and total cholesterol (TC) with doses ≥500mg {MD=-13.34, 95%CI [-22.73, -3.95], P=0.005}, {MD=-5.64, 95%CI [-6.95, -4.33], P<0.00001} respectively. Moreover, it improved HbA1c at three months {MD=-0.41, 95%CI [-0.65, -0.16], P=0.001 and systolic blood pressure {MD: -7.91, 95%CI [-10.44, -5.37], P<0.00001}.

CONCLUSION

We concluded that resveratrol beneficially modulates glycemic control as well as cardiometabolic parameters in patients with T2DM.

Efficacy and Safety of Resveratrol Supplements on Blood Lipid and Blood Glucose Control in Patients with Type 2 Diabetes: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background

Diabetes is a major public health concern. Resveratrol has shown great beneficial effects on hyperglycemia and insulin resistance and as an antioxidant.

Methods

We searched the Chinese and English databases (such as CNKI, PubMed, and Embase) and extracted data from randomized controlled trials (RCTs). Then, RevMan 5.3 was used for bias risk assessment and meta-analysis. The primary outcome indicators include insulin-resistance-related indicators and blood-lipid-related indicators. This systematic review and meta-analysis was registered in PROSPERO (CRD42018089521).

Results

Fifteen RCTs involving 896 patients were included. For insulin-resistance-related indicators, the summary results showed that, compared with the control group, homeostasis model assessment for insulin resistance (HOMA-IR) in the resveratrol group is lower (WMD: −0.99; 95% CI −1.61, −0.38; P=0.002). For blood-lipid-related indicators, the total cholesterol (TC) and triglyceride (TG) in the resveratrol group is of no statistical significance (for TC, WMD: −7.11; 95% CI −16.28, 2.06; P=0.13; for TG, WMD: −2.15; 95% CI −5.52, 1.22; P=0.21). For adverse events, the summary results showed that there was no statistical difference in the incidence of adverse events between the resveratrol and control groups (WMD: 2; 95% CI 0.44, 9.03; P=0.37).

Conclusion

Based on the current evidence, resveratrol may improve insulin resistance, lower fasting blood glucose and insulin levels, and improve oxidative stress in patients with type 2 diabetes mellitus.

Enhancing Bioavailability of Nutraceutically Used Resveratrol and Other Stilbenoids

Stilbenoids are interesting natural compounds with pleiotropic in vitro and in vivo activity. Their well-documented biological properties include anti-inflammatory effects, anticancer effects, effects on longevity, and many others. Therefore, they are nowadays commonly found in foods and dietary supplements, and used as a part of treatment strategy in various types of diseases. Bioactivity of stilbenoids strongly depends on different types of factors such as dosage, food composition, and synergistic effects with other plant secondary metabolites such as polyphenols or vitamins. In this review, we summarize the existing in vitro, in vivo, and clinical data from published studies addressing the optimization of bioavailability of stilbenoids. Stilbenoids face low bioavailability due to their chemical structure. This can be improved by the use of novel drug delivery systems or enhancers, which are discussed in this review. Current in vitro and in vivo evidence suggests that both approaches are very promising and increase the absorption of the original substance by several times. However, data from more clinical trials are required.

Pharmaceutical Drugs and Natural Therapeutic Products for the Treatment of Type 2 Diabetes Mellitus

Type 2 diabetes mellitus (T2DM) is the most widespread form of diabetes, characterized by chronic hyperglycaemia, insulin resistance, and inefficient insulin secretion and action. Primary care in T2DM is pharmacological, using drugs of several groups that include insulin sensitisers (e.g., biguanides, thiazolidinediones), insulin secretagogues (e.g., sulphonylureas, meglinides), alpha-glucosidase inhibitors, and the newest incretin-based therapies and sodium-glucose co-transporter 2 inhibitors. However, their long-term application can cause many harmful side effects, emphasising the importance of the using natural therapeutic products. Natural health substances including non-flavonoid polyphenols (e.g., resveratrol, curcumin, tannins, and lignans), flavonoids (e.g., anthocyanins, epigallocatechin gallate, quercetin, naringin, rutin, and kaempferol), plant fruits, vegetables and other products (e.g., garlic, green tea, blackcurrant, rowanberry, bilberry, strawberry, cornelian cherry, olive oil, sesame oil, and carrot) may be a safer alternative to primary pharmacological therapy. They are recommended as food supplements to prevent and/or ameliorate T2DM-related complications. In the advanced stage of T2DM, the combination therapy of synthetic agents and natural compounds with synergistic interactions makes the treatment more efficient. In this review, both pharmaceutical drugs and selected natural products, as well as combination therapies, are characterized. Mechanisms of their action and possible negative side effects are also provided.

Resveratrol and Markers of Polycystic Ovary Syndrome: a Systematic Review of Animal and Clinical Studies

Polycystic ovary syndrome (PCOS) is a common disorder affecting childbearing-age women, and is associated with reproductive and metabolic disturbances. The present study aimed to systematically review current animal studies and randomized placebo-controlled clinical trials (RCT) regarding the effects of resveratrol, a natural polyphenolic compound, on PCOS features. PubMed, Scopus, Web of Knowledge, and Google Scholar were comprehensively searched until December 2020. All original animal articles and RCTs evaluating the effects of resveratrol on PCOS were eligible for the review. Out of 289 initial records, eight animal studies and three RCTs met our inclusion criteria. Most of the included animal studies reported beneficial effects of resveratrol on the histomorphological features, sex hormones and gonadotropins, glycemic control, inflammation, and oxidative stress. Resveratrol also ameliorated ovarian volume, high-quality oocyte rate, high-quality embryo rate, androgens and gonadotropins concentrations, angiogenic factors levels, and endoplasmic reticulum stress in PCOS patients. Upregulation of sirtuin-1 was an examined mechanism proposed for some observed effects of resveratrol. The current literature is limited to conclude the beneficial effects of resveratrol on the management of PCOS. Although, according to the promising results of the animal studies and limited RCTs, resveratrol might be an effective phytochemical in PCOS control, especially regarding hormonal and reproductive abnormalities. More mechanistic studies and RCTs are warranted to obvious whether resveratrol can be prescribed in the clinical situation.

Resveratrol and endothelial function: A literature review

Endothelial dysfunction is a major contributing factor to diseases such as atherosclerosis, diabetes mellitus, obesity, hypertension, acute lung injury, preeclampsia, among others. Resveratrol (RSV) is a naturally occurring bioactive polyphenol found in grapes and red wine. According to experimental studies, RSV modulates several events involved in endothelial dysfunction such as impaired vasorelaxation, eNOS uncoupling, leukocyte adhesion, endothelial senescence, and endothelial mesenchymal transition. The endothelial protective effects of RSV are found to be mediated by numerous molecular targets (e.g. Silent Information Regulator 1 (SIRT1), 5' AMP-activated protein kinase (AMPK), endothelial nitric oxide synthase (eNOS), nuclear factor-erythroid-derived 2-related factor-2 (Nrf2), peroxisome proliferator-activated receptor (PPAR), Krüppel-like factor-2 (KLF2), and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB)). Herein, we present an updated review addressing pharmacological effects and molecular targets of RSV in maintaining endothelial function, and the potential of this phytochemical for endothelial dysfunction-associated disorders.

Resveratrol attenuates dapagliflozin-induced renal gluconeogenesis via activating the PI3K/Akt pathway and suppressing the FoxO1 pathway in type 2 diabetes

Dapagliflozin alleviates hyperglycemia by increasing glycosuria, but it induces renal gluconeogenesis, thus neutralizing its efficacy. Resveratrol (Rsv), a natural polyphenolic chemical, improves insulin sensitivity in type 2 diabetes (T2D). Here, we investigated the regulatory effects and underlying mechanisms of Rsv on dapagliflozin-induced renal gluconeogenesis. Male ob/ob mice were given the vehicle (HF), dapagliflozin (1 mg kg-1), Rsv (10 mg kg-1), or dapagliflozin and Rsv combination for 10 weeks. Glucose metabolism was evaluated by glucose and pyruvate tolerance tests. HK-2 cells (human renal proximal tubule cells) were treated with dapagliflozin (1 μmol L-1) for 2 h and further incubated with Rsv (10 μmol L-1) for 12 h. The effects of Rsv on gluconeogenesis and insulin signaling were assessed. Dapagliflozin treatment increased glucose production in HK-2 cells and lowered blood glucose and induced gluconeogenesis in ob/ob mice. After Rsv treatment, the enhanced glucose production and gluconeogenesis were alleviated. The upregulated mRNA and protein expression of phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase) and the activation of the forkhead transcription factor O1 (FoxO1) protein in the dapagliflozin group were attenuated by Rsv administration. Rsv also improved renal insulin signaling by increasing PI3K and Akt phosphorylation. The PI3K inhibitor LY294002 dramatically decreased the p-Akt expression and activated FoxO1 by dephosphorylation, thus diminishing the inhibitory effects of Rsv on dapagliflozin-induced PEPCK and G6Pase expression. The data showed the mechanisms of Rsv in attenuating dapagliflozin-induced renal gluconeogenesis via activating the PI3K/Akt pathway and further suppressing FoxO1 activation, suggesting a potential intervention to achieve better glucose-lowering effects for SGLT2 inhibitors in T2D therapy.

The impact of resveratrol on skin wound healing, scarring, and aging

Resveratrol is a well‐known antioxidant that harbours many health beneficial properties. Multiple studies associated the antioxidant, anti‐inflammatory, and cell protective effects of resveratrol. These diverse effects of resveratrol are also potentially involved in cutaneous wound healing, scarring, and (photo‐)aging of the skin. Hence, this review highlighted the most relevant studies involving resveratrol in wound healing, scarring, and photo‐aging of the skin. A systematic review was performed and the database PubMed was searched for suitable publications. Only original articles in English that investigated the effects of resveratrol in wound healing, scarring, and (photo‐)aging of the skin were analysed. The literature search yielded a total of 826 studies, but only 41 studies met the inclusion criteria. The included studies showed promising results that resveratrol might be a feasible treatment approach to support wound healing, counteract excessive scarring, and even prevent photo‐aging of the skin. Resveratrol represents an interesting and promising novel therapy regime but to confirm resveratrol‐associated effects, more evidence based in vitro and in vivo studies are needed.

Effects of Maternal Resveratrol Intake on the Metabolic Health of the Offspring

Maternal nutritional imbalances, in addition to maternal overweight and obesity, can result in long-term effects on the metabolic health of the offspring, increasing the risk of common non-communicable disorders such as obesity, diabetes and cardiovascular disease. This increased disease risk may also be transmitted across generations. Unfortunately, lifestyle interventions have shown reduced compliancy and limited efficacy. Resveratrol is a natural polyphenolic compound reported to have pleiotropic beneficial actions including a possible protective effect against the metabolic programming induced by poor dietary habits during development. However, studies to date are inconclusive regarding the potential metabolic benefits of maternal resveratrol supplementation during pregnancy and lactation on the offspring. Moreover, the responses to metabolic challenges are suggested to be different in males and females, suggesting that the effectiveness of treatment strategies may also differ, but many studies have been performed only in males. Here we review the current evidence, both in humans and animal models, regarding the possible beneficial effects of maternal resveratrol intake on the metabolic health of the offspring and highlight the different effects of resveratrol depending on the maternal diet, as well as the differential responses of males and females.

Impact of resveratrol in the reduction of the harmful effect of diabetes on peri-implant bone repair: bone-related gene expression, counter-torque and micro-CT analysis in rats

OBJECTIVE

Investigate the impact of resveratrol (RESV) on peri-implant repair and its effect on bone-related markers in rats with induced diabetes mellitus (DM).

MATERIAL AND METHODS

Ninety rats were divided into: DM + RESV (n = 18); DM + placebo (PLAC) (n = 18); DM + insulin (INS) (n = 18); DM + RESV + INS (n = 18); Non-DM (n = 18). Diabetes was induced by streptozotocin. One screw-shaped titanium implant was inserted in each tibiae of animals. Treatments were administered during 30 days. After, one of the implants was removed for counter-torque and the peri-implant tissue was collected for mRNA quantification of BMP-2, OPN, Runx2, Lrp-5, Osx, β-catenin, Dkk1, OPG, and RANKL by Real-time PCR. The other tibia was submitted to MicroCT analysis to measure: bone volume (BV/TV), trabecular thickness (Tb.Th) and bone-implant contact (BIC).

RESULTS

Higher counter-torque values were observed for implant removal in DM + RESV, DM + RESV + INS and Non-DM groups when compared to DM + PLAC (p < .05). Augmented Tb.Th was observed in DM + RESV and Non-DM when compared to DM + PLAC group (p < .05), whereas higher BIC was detected in DM + RESV, DM + RESV + INS and Non-DM animals when compared to DM + PLAC (p < .05). Levels of RANKL were downregulated by the RESV and/or INS therapy, whereas only the association of RESV and INS upregulated the levels of Runx2 (p < .05).

CONCLUSIONS

The therapy with RESV may favour peri-implant bone repair improving bone formation around implants.