The role of resveratrol in diabetes and obesity associated with insulin resistance

The protective role of resveratrol against high glucose-induced oxidative stress and apoptosis in HepG2 cells

High glucose concentrations result in oxidative stress, leading to damage of cellular constituents like DNA, proteins, and lipids, ultimately resulting in apoptosis. Resveratrol, a polyphenol phytoalexin, has been studied for its potential therapeutic effects on diabetes. This study investigated the influence of high glucose (HG) on HepG2 cells and assessed resveratrol's effect on high-glucose-induced oxidative stress and apoptosis. HepG2 cells were cultured for 48 and 72 h with high glucose (40 mM), low resveratrol (25 μM), high resveratrol (50 μM), high glucose + low resveratrol, and high glucose + high resveratrol. After exposure, oxidative and apoptosis-related gene expression was evaluated using quantitative polymerase chain reaction (qPCR), and lactate dehydrogenase (LDH) release was measured using the supernatant. In HepG2 cells cultured with high glucose, all antioxidant enzymes (SOD, superoxide dismutase; GPx1, glutathione peroxidase 1; CAT, catalase; Nrf2, nuclear factor erythroid 2-related factor 2; and NQO1, NAD(P)H quinone oxidoreductase 1) were significantly reduced; however, when HepG2 cells were cultured with resveratrol (25 and 50 μM) and high glucose, the expression levels of all antioxidant enzymes were increased. The anti-apoptotic gene (B-cell lymphoma 2; Bcl2) and the DNA repair gene (Oxoguanine glycosylase-1, OGG1) were significantly decreased following high glucose exposure to HepG2 cells. Surprisingly, the expression levels of Bcl2 and OGG1 were notably elevated after resveratrol treatment. Furthermore, high glucose levels increased the LHD release in HepG2 cells, whereas resveratrol treatment reduced the LDH release. Our results demonstrate that resveratrol provides protection against oxidative stress and apoptosis induced by high glucose in HepG2 cells. Hence, resveratrol shows potential as an effective approach to address the impaired antioxidant response resulting from elevated glucose levels commonly observed in diabetes and metabolic disorders.

Exploring the multimodal health-promoting properties of resveratrol: A comprehensive review

Resveratrol, a natural polyphenol in various plants, has gained significant attention for its potential health-promoting properties. It has been demonstrated, after reviewing various clinical and in vitro studies, that resveratrol possesses potent antioxidant potential. Resveratrol demonstrates cellular component protection by directly neutralizing free radicals (FRs) and enhancing the expression of natural antioxidant enzymes, thereby mitigating oxidative damage to proteins, lipids, and nucleic acids. Clinical trials have shown promising results, indicating that resveratrol supplementation can enhance antioxidant defenses and reduce oxidative damage markers in various populations. In addition to its antioxidant effects, resveratrol exhibits potent anti-inflammatory properties. It can modulate key inflammatory pathways, such as nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinases (MAPKs), thereby suppressing the production of pro-inflammatory cytokines and chemokines. Furthermore, resveratrol's multimodal effects extend beyond its antioxidant and anti-inflammatory properties. It has been discovered to exert regulatory effects on various cellular processes, including apoptosis, cell cycle progression, angiogenesis, and immunological responses. The primary aim of this review paper is to provide a thorough overview of the current knowledge on resveratrol, including its chemical composition, bioaccessibility, clinical effectiveness, and utilization in nanotechnology to enhance its bioavailability. From future perspectives, revising the administration methods for certain contexts and understanding the underlying systems responsible for resveratrol's effects will require further inquiry. For the highest potential health results, advanced trial-based research is necessary for combinational nano-delivery of resveratrol.

Resveratrol protects mesangial cells under high glucose by regulating the miR-1231/IGF1/ERK pathway

Diabetic nephropathy (DN) is one of the complications of diabetes mellitus and the main cause of end-stage renal disease (ESRD), which is a serious threat to human health. In DN, mesangial cells (MCs) are a critical target cell that perform a variety of key functions, and abnormal proliferation of MCs is a common and prominent pathological change in DN. In recent years, the investigation of Chinese medicine interventions for DN has increased significantly in recent years due to the many potential adverse effects and controversies associated with the treatment of DN with Western medicines. In this study, we evaluated the protective effect of resveratrol (RES), an active ingredient known as a natural antioxidant, on HMCs under high glucose and explored its possible mechanism of action. We found that RES inhibited the proliferation of human mesangial cell (HMC) under high glucose and blocked cell cycle progression. In the high glucose environment, RES upregulated miR-1231, reduced IGF1 expression, inhibited the activity of the extracellular signal-regulated kinase (ERK) signaling pathway and reduced levels of the inflammatory factors TNF-α and IL-6. In addition, we found that miR-1231 mimics were synergistically inhibited with RES, whereas miR-1231 inhibitor attenuated the protective effect of RES on HMCs. Thus, our results suggest that the protective effect of RES on HMCs under high glucose is achieved, at least in part, through modulation of the miR-1231/IGF1/ERK pathway. The discovery of this potential mechanism may provide a new molecular therapeutic target for the prevention and treatment of DN, and may also bring new ideas for the clinical research in DN.

Clinically Effective Molecules of Natural Origin for Obesity Prevention or Treatment

The prevalence and incidence of obesity and the comorbidities linked to it are increasing worldwide. Current therapies for obesity and associated pathologies have proven to cause a broad number of adverse effects, and often, they are overpriced or not affordable for all patients. Among the alternatives currently available, natural bioactive compounds stand out. These are frequently contained in pharmaceutical presentations, nutraceutical products, supplements, or functional foods. The clinical evidence for these molecules is increasingly solid, among which epigallocatechin-3-gallate, ellagic acid, resveratrol, berberine, anthocyanins, probiotics, carotenoids, curcumin, silymarin, hydroxy citric acid, and α-lipoic acid stand out. The molecular mechanisms and signaling pathways of these molecules have been shown to interact with the endocrine, nervous, and gastroenteric systems. They can regulate the expression of multiple genes and proteins involved in starvation-satiety processes, activate the brown adipose tissue, decrease lipogenesis and inflammation, increase lipolysis, and improve insulin sensitivity. This review provides a comprehensive view of nature-based therapeutic options to address the increasing prevalence of obesity. It offers a valuable perspective for future research and subsequent clinical practice, addressing everything from the molecular, genetic, and physiological bases to the clinical study of bioactive compounds.

Gut microbiota: The key to the treatment of metabolic syndrome in traditional Chinese medicine - a case study of diabetes and nonalcoholic fatty liver disease

Metabolic syndrome mainly includes obesity, type 2 diabetes (T2DM), alcoholic fatty liver (NAFLD) and cardiovascular diseases. According to the ancient experience philosophy of Yin-Yang, monarch-minister compatibility of traditional Chinese medicine, prescription is given to treat diseases, which has the advantages of small toxic and side effects and quick effect. However, due to the diversity of traditional Chinese medicine ingredients and doubts about the treatment theory of traditional Chinese medicine, the mechanism of traditional Chinese medicine is still in doubt. Gastrointestinal tract is an important part of human environment, and participates in the occurrence and development of diseases. In recent years, more and more TCM researches have made intestinal microbiome a new frontier for understanding and treating diseases. Clinically, nonalcoholic fatty liver disease (NAFLD) and diabetes mellitus (DM) often co-occur. Our aim is to explain the mechanism of interaction between gastrointestinal microbiome and traditional Chinese medicine (TCM) or traditional Chinese medicine formula to treat DM and NAFLD. Traditional Chinese medicine may treat these two diseases by influencing the composition of intestinal microorganisms, regulating the metabolism of intestinal microorganisms and transforming Chinese medicinal compounds.

A meta-analysis of resveratrol protects against cerebral ischemia/reperfusion injury: Evidence from rats studies and insight into molecular mechanisms

Objective: To evaluate the neuroprotective effect of resveratrol (RES) in rat models of cerebral ischemia/reperfusion (I/R) injury.

Data sources: PubMed, Embase, MEDLINE, Cochrane Library, and Chinese databases were searched from their inception dates to July 2022. No language restriction was used in the literature search.

Date Selection: Studies were selected that RES were used to treat cerebral I/R injury in vivo. Two reviewers conducted literature screening, data extraction and methodological quality assessment independently.

Outcome measures: Cerebral infarct volume was included as primary outcome. The secondary outcomes included cerebral water content and neurological deficit scores. Malondialdehyde (MDA) and superoxide dismutase (SOD) were used to evaluate oxidative stress during medication.

Results: A total of 41 studies were included, and only a few of them the methodological quality was relatively low. Compared with the control group, RES significantly reduced the cerebral infarct volume (29 studies, standard mean difference (SMD) = −2.88 [−3.23 to −2.53], p < 0.00001) and brain water content (nine studies, MD = −9.49 [−13.58 to −5.40], p < 0.00001) after cerebral I/R injury, then neurological function was improved (15 studies, SMD = −1.96 [−2.26 to −1.65], p < 0.00001). The MDA level (six studies, SMD = −8.97 [−13.60 to −4.34], p = 0.0001) was decreased notably after treatment of RES, while the SOD level (five studies, SMD = 3.13 [−0.16 to 6.43], p = 0.06) was increased unsatisfactory. Consistently, subgroup analysis of cerebral infarct volume suggested that the optimal therapeutic dose is 30 mg/kg (eight studies, SMD = −5.83 [−7.63 to −4.04], p < 0.00001). Meanwhile, 60 min of occlusion (three studies, SMD = −10.89 [−16.35 to −5.42], p < 0.0001) could get maximum benefit from compared with 90 min and 120 min of occlusion. On the other hand, the publication bias cannot be ignored. The pharmacological mechanisms of RES on cerebral I/R injury models as reported have be summarized, which can be used for reference by researchers to further plan their future experiments.

Conclusion: RES might have a good neuroprotective effect on cerebral I/R injury in rats, then 30 mg/kg RES may be the optimal dose for treatment, and early administration of RES should be more neuroprotective. Also it need to be further verified through exploration of dose effect relationship, or delay administration or not.

The Role and Regulatory Mechanism of Brown Adipose Tissue Activation in Diet-Induced Thermogenesis in Health and Diseases

Brown adipose tissue (BAT) has been considered a vital organ in response to non-shivering adaptive thermogenesis, which could be activated during cold exposure through the sympathetic nervous system (SNS) or under postprandial conditions contributing to diet-induced thermogenesis (DIT). Humans prefer to live within their thermal comfort or neutral zone with minimal energy expenditure created by wearing clothing, making shelters, or using an air conditioner to regulate their ambient temperature; thereby, DIT would become an important mechanism to counter-regulate energy intake and lipid accumulation. In addition, there has been a long interest in the intriguing possibility that a defect in DIT predisposes one to obesity and other metabolic diseases. Due to the recent advances in methodology to evaluate the functional activity of BAT and DIT, this updated review will focus on the role and regulatory mechanism of BAT biology in DIT in health and diseases and whether these mechanisms are applicable to humans.

Biochemical Investigation of Therapeutic Potentials of Plant-Based Bioactive Compounds as Stimulators of Glucagon like peptide-1 Secretion

This study was aimed to investigate the therapeutic potentials of plant-based bioactive compounds; lutein and resveratrol alone and/or in combination with DPP-4 enzyme inhibitor; sitagliptin on the secretion and bioavailability of Glucagon like peptide-1(GLP). For this, experimental rats were divided into seven groups. Group 1 was marked as control, while other six groups received streptozotocin (60 mg/kg I.P.). Later, group 2 was kept disease-control. While group 3 received 10 mg/kg/day sitagliptin (DDP-4i). Group 4 received 40 mg/kg/day lutein (LUT) and group 5 received 30 mg/kg/day resveratrol (RES). While group 6 and 7 were received combination of DPP-4i+LUT and DPP-4i+RES, respectively. Combined administration of DPP-4i+LUT or DPP-4i+RES showed expected therapeutic effects by lowering the fasting blood glucose and maintaining the serum insulin concentrations with improved glucose sensitivity and reduced insulin resistance. Further, co-administration of LUT and RES with DPP-4i revealed beneficial effects on measures of insulin resistance, circulating lipids, glycemic index, oxidative stress, and inflammatory status along with restoration of histological morphology of pancreatic cells and enterocytes that seemed to improve the level of GLP-1. Hence, substantial verdicts of this study showing therapeutic potentials of LUT and RES would surely help to recognize the potential effects in combination with DPP-4i as stimulators of GLP-1 secretion.

Lockdown of mitochondrial Ca2+ extrusion and subsequent resveratrol treatment kill HeLa cells by Ca2+ overload

Anticancer effect of resveratrol and the role of sodium/lithium/calcium exchanger in context with calcium ions are studied in human cervical cancer cell line. This therapeutic approach using siNCLX mediated gene silencing and drug therapy with resveratrol indicates the disruption of calcium homeostasis, increase in caspase (-3, 8, 9) mRNA expressions and DNA damage leading to apoptotic cell death. Monitoring the intracellular Ca2+ changes using fluo-4AM indicates highest rise in [Ca2+] level in sodium/lithium/calcium exchanger silenced group with five different stages, that is distinguishable based on the fluorescence intensity. In resveratrol treated and siNCLX + resveratrol treated groups no such cell staging differences were observed, despite uniform Ca2+ rise followed by decrease in the intensity. Integrating RNAi gene silencing of sodium/lithium/calcium exchanger with resveratrol can form the most interesting, efficient and promising therapeutic strategy in the treatment of cancer.

A Brief Updated Review of Advances to Enhance Resveratrol's Bioavailability

Resveratrol (RES) has a low bioavailability. This limitation was addressed in an earlier review and several recommendations were offered. A literature search was conducted in order to determine the extent of the research that was conducted in line with these recommendations, along with new developments in this field. Most of the identified studies were pre-clinical and confirmed the heightened activity of RES analogues compared to their parent compound. Although this has provided additional scientific kudos for these compounds and has strengthened their potential to be developed into phytopharmaceutical products, clinical trials designed to confirm this increased activity remain lacking and are warranted.