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

Epigenetic and Mitochondrial Metabolic Dysfunction in Multiple Sclerosis: A Review of Herbal Drug Approaches and Current Clinical Trials

Multiple sclerosis (MS) is a complex autoimmune disease characterised by inflammation, demyelination, and neurodegeneration within the central nervous system (CNS). While the exact causes remain unclear, recent research highlights the significant role of epigenetic modifications and mitochondrial dysfunction in the disease's onset and progression. Epigenetic alterations, such as DNA methylation, histone modification, and microRNA regulation, influence gene expression without altering the DNA sequence, leading to immune dysregulation and inflammation. Similarly, mitochondrial dysfunction, marked by impaired oxidative phosphorylation, reduced adenosine triphosphate (ATP) production, and increased reactive oxygen species (ROS), contributes to neurodegeneration and impaired remyelination in MS. The growing interest in targeting these two interconnected mechanisms has opened new avenues for MS treatment. Herbal drugs, known for their multi-targeted effects, have shown potential in modulating epigenetic markers and enhancing mitochondrial function. Compounds such as resveratrol, curcumin, epigallocatechin-3-gallate (EGCG), quercetin, and omega-3 fatty acids demonstrate potential in regulating DNA methylation, histone deacetylation, and mitochondrial biogenesis. These natural agents offer dual-action therapies by reducing oxidative stress and inflammation while promoting neuronal survival and remyelination. This review explores the therapeutic potential of herbal drugs targeting epigenetic and mitochondrial pathways in MS, evaluating their mechanisms of action and highlighting their promise as novel therapeutic agents. While initial findings are encouraging, further research and clinical trials are required to validate the efficacy of these herbal treatments and fully understand their potential in slowing disease progression and improving patient outcomes in MS. Such exploration could pave the way for safer, multi-targeted therapies, offering new hope in the management of MS and other neurodegenerative diseases.

A Panel of Diverse Inflammatory Biomarkers Is Not Associated with BMI-Calibrated Obesity nor with Dyslipidemia or Dysglycemia in Clinically Healthy Adults Aged 20 to 40 Years

OBJECTIVES

Low-grade metabolic inflammation is associated with several chronic metabolic disorders, including obesity. However, no concrete evidence that supports obesity as a direct cause of chronic inflammation. This study aims to identify the association of inflammation with obesity in apparently healthy adults.

METHODS

In this study, 162 seemingly healthy volunteers, aged between 20 and 40 years, of comparable sex ratio, were recruited and categorized based on their body mass index (BMI) into four obesity scales: normal (N), overweight (OW), obese (OB), and severely obese (SOB). After clinical examination, fasting blood samples were collected from the study subjects for glycemic (fasting blood glucose-FBG, and HbA1c) and lipid (total cholesterol, LDL-C, HDL-C, and triacyl glycerides -TAG) profile analysis. In addition, plasma levels of a panel of diverse inflammatory biomarkers, IL6, IL8, procalcitonin (PCT), TREM1, and uPAR were analyzed by sandwich ELISA.

RESULTS

The results showed that LDLC, TAG, FBG, and HbA1c were significantly higher in the obese (OB and SOB) group, compared to the non-obese (N and OW) group, while HDLc was significantly lower. The biomarker levels were not correlated with age or significantly differed between males and females. Importantly, levels of all assessed inflammatory biomarkers were comparable between the obesity classes. Moreover, the assessed biomarkers in subjects with dyslipidemia or dysglycemia were comparable to those with normal profiles. Finally, the biomarker levels were not correlated with the obesity, glycemic, or lipidemic parameters.

CONCLUSIONS

After correction for age and co-morbidities, our results deny the association of discrete obesity, probably dyslipidemia, and dysglycemia with systemic chronic inflammation. Further studies of local and systemic inflammation in non-elderly, healthy obese subjects are needed.

Effect of resveratrol supplementation on metabolic risk markers and anthropometric parameters in individuals with obesity or overweight: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Obesity, a progressively widespread disease with a multifaceted etiology, affects nearly 800 million people worldwide. Recent trials suggest that resveratrol, a polyphenolic compound, can be effective for metabolic risk markers and anthropometric parameters in Individuals with Obesity or Overweight. However, a comprehensive analysis is necessary to consolidate these results.

OBJECTIVES

To evaluate the impact of 4-week resveratrol supplementation on metabolic risk markers and anthropometric parameters in individuals with obesity or overweight.

METHODS

A comprehensive search was executed across PubMed, Cochrane Library, Scopus, Google Scholar, and clinicaltrials.gov, yielding 43 studies after the omission of 20 duplicates. RevMan 5.4 software was used to statistically analyze randomized controlled studies to gauge the impact of resveratrol on the said outcomes in Individuals with Obesity or Overweight. Quality of bias and potential publication bias were measured using the Cochrane Risk of Bias tool and CMA4 software, respectively. Certainty of the evidence was appraised using GRADEpro software. Data was quantified as the standardized mean difference (SMD) and 95 % confidence intervals (CI).

RESULTS

The meta-analysis included 5 trials with 419 participants, evaluating the effect of intervention. Resveratrol showed no significant impact on triglycerides (SMD = 0.11, 95%CI [-0.14, 0.35], P = 0.39, I2 = 0 %), total cholesterol (SMD = 0.04, 95%CI [-0.26, 0.33], P = 0.82, I2 = 0 %), or HbA1c (SMD = 0.00, 95%CI [-0.99, 1.00], P = 0.99, I2 = 80 %). Similarly, no significant effect was observed for insulin levels (SMD = -0.00, 95%CI [-0.25, 0.24], P = 0.97, I2 = 0 %), AST (SMD = 0.15, 95%CI [-0.35, 0.65], P = 0.55, I2 = 0 %), or ALT (SMD = -0.03, 95%CI [-0.46, 0.39], P = 0.98, I2 = 0 %). Additionally, resveratrol had no significant effect on BMI (MD = 0.21, 95%CI [-0.970, 1.39], P = 0.70, I2 = 0 %).

CONCLUSIONS

Our results tagged with p-value>0.05 are an evidence-based indication that resveratrol supplementation does not lead to significant improvements in metabolic or anthropometric parameters. This suggests that resveratrol may not be an effective standalone intervention for managing obesity-related outcomes. Therefore, future research should be redirected to evaluating its potential effects on other health metrics to elucidate its efficacy and therapeutic potential better.

Polyphenol Intervention Ameliorates Non-Alcoholic Fatty Liver Disease: An Updated Comprehensive Systematic Review

Non-alcoholic fatty liver disease (NAFLD) has recently emerged as a challenging metabolic disorder with a strong emphasis on its prevention and management. Polyphenols, a group of naturally occurring plant compounds, have been associated with a decreased risk of various metabolic disorders related to NAFLD. The current systematic review aims to critically assess evidence about the ameliorative effect of polyphenol supplementation on NAFLD patients. A PRISMA systematic search appraisal was conducted in PubMed, Scopus, Web of Science Core Collection, and all relevant studies published prior to April 2024 and met the inclusion criteria were included. Twenty-nine randomized clinical trials (RCTs) comprised 1840 NAFLD patients. The studies primarily examined eleven phenolic compounds, including turmeric, curcumin, resveratrol, genistein, catechin, green tea extract, hesperidin, and silymarin. Turmeric and curcumin decreased liver enzymes, inflammatory cytokines, lipid profile, insulin resistance, and NAFLD score, while resveratrol did not present consistent results across all the studies. Most studies on silymarin showed a reduction in liver enzymes and lipid profile; however, no changes were observed in inflammatory cytokine levels. The dietary supplementation of hesperidin and naringenin or green tea extract caused improvements in liver enzyme, lipid profile, and inflammatory cytokine, while genistein supplementation did not modulate blood lipid profile. In conclusion, dietary supplementation of polyphenols could potentially prevent and ameliorate NAFLD. Still, the inconsistent results across the included RCTs require further clinical research to establish optimal dosage and duration.

Non-apoptotic cell death in osteoarthritis: Recent advances and future

Osteoarthritis (OA) is the most common degenerative joint disease. Multiple tissues are altered during the development of OA, resulting in joint pain and permanent damage to the osteoarticular joints. Current research has demonstrated that non-apoptotic cell death plays a crucial role in OA. With the continuous development of targeted therapies, non-apoptotic cell death has shown great potential in the prevention and treatment of OA. We systematically reviewed research progress on the role of non-apoptotic cell death in the pathogenesis, development, and outcome of OA, including autophagy, pyroptosis, ferroptosis, necroptosis, immunogenic cell death, and parthanatos. This article reviews the mechanism of non-apoptotic cell death in OA and provides a theoretical basis for the identification of new targets for OA treatment.

Review on the Role of Polyphenols in Preventing and Treating Type 2 Diabetes: Evidence from In Vitro and In Vivo Studies

Type 2 diabetes (T2D) is one of the leading causes of death globally. There was a 70% increase in diabetes-related deaths between 2000 and 2020, particularly among males. This non-communicable disease is characterized by increased insulin resistance, leading to elevated blood sugar levels and, if untreated, resulting in complications such as nerve damage, kidney disease, blindness, and poor wound healing. T2D management includes dietary intervention, physical exercise, and the administration of blood sugar-lowering medication. However, these medications often have side effects related to intestinal discomfort. Therefore, natural alternatives to standard diabetes medications are being sought to improve the quality of life for individuals with this condition. Polyphenols, which are naturally occurring plant metabolites, have emerged as strong candidates for T2D control. Various phenolic acids (e.g., chlorogenic acid), flavonoids (e.g., quercetin), proanthocyanidins (e.g., procyanidin B2), gallotannins (e.g., monogalloyl hexoside), and ellagitannins (e.g., ellagic acid hexoside) can enhance insulin sensitivity in tissues, reduce chronic inflammation, scavenge free radicals, improve insulin secretion, inhibit enzymes involved in carbohydrate digestion, regulate glucose transport across cell membranes, and modulate gut microbiota. This contribution compiles up-to-date evidence from in vitro and in vivo studies on the role of polyphenols in the prevention and management of T2D, emphasizing the mechanisms of action underlying these effects.

Evaluation of cadmium effects on the glucose metabolism on insulin resistance HepG2 cells

Cadmium (Cd) is an environmental endocrine disruptor. Despite increasing research about the metabolic effects of Cd on HepG2 cells, information about the metabolic effects of Cd on insulin resistance HepG2 (IR-HepG2) cells is limited. Currently, most individuals with diabetes are exposed to Cd due to pollution. Previously, we reported that Cd exposure resulted in decreased blood glucose levels in diabetic mice, the underlying mechanism deserves further study. Therefore, we used palmitic acid (0.25 mM) to treat HepG2 cells to establish IR-HepG2 model. IR-HepG2 cells were exposed to CdCl2 (1 μM and 2 μM). Commercial kits were used to measure glucose production, glucose consumption, ROS and mitochondrial membrane potential. Western blot and qRT-PCR were used to measure the proteins and genes of glucose metabolism. In the current study setting, we found no significant changes in glucose metabolism in Cd-exposed HepG2 cells, but Cd enhanced glucose uptake, inhibited gluconeogenesis and activated the insulin signaling pathway in IR-HepG2 cells. Meanwhile, we observed that Cd caused oxidative stress and increased the intracellular calcium concentration and inhibited mitochondrial membrane potential in IR-HepG2 cells. Cd compensatingly increased glycolysis in IR-HepG2 cells. Collectively, we found Cd ameliorated glucose metabolism disorders in IR-HepG2 cells. Furthermore, Cd exacerbated mitochondrial damage and compensatory increased glycolysis in IR-HepG2 cells. These findings will provide novel insights for Cd exposure in insulin resistant individuals.

Marine-Derived Phosphoeleganin and Its Semisynthetic Derivative Decrease IL6 Levels and Improve Insulin Signaling in Human Hepatocellular Carcinoma Cells

Marine natural products constitute a great source of potential new antidiabetic drugs. The aim of this study was to evaluate the role of phosphoeleganin (PE), a polyketide purified from the Mediterranean ascidian Sidnyum elegans, and its derivatives PE/2 and PE/3 on insulin sensitivity in human hepatocellular carcinoma (HepG2) cells. In our experiments, insulin stimulates the phosphorylation of its receptor (INSR) and AKT by 1.5- and 3.5-fold, respectively, whereas in the presence of PE, PE/2, and PE/3, the insulin induced INSR phosphorylation is increased by 2.1-, 2-, and 1.5-fold and AKT phosphorylation by 7.1-, 6.0-, and 5.1-fold, respectively. Interestingly, PE and PE/2 have an additive effect on insulin-mediated reduction of phosphoenolpyruvate carboxykinase (PEPCK) expression. Finally, PE and PE/2, but not PE/3, decrease interleukin 6 (IL6) secretion and expression before and after palmitic acid incubation, while in the presence of high glucose (HG), only PE reduces IL6. Levels of other cytokines are not significantly affected by PE and its derivates. All these data suggest that PE and its synthetic-derived compound, PE/2, significantly decrease IL6 and improve hepatic insulin signaling. As IL6 impairs insulin action, it could be hypothesized that PE and PE/2, by inhibiting IL6, may improve the hepatic insulin pathway.

Glucose inhibits the inflammatory response in goose fatty liver by increasing the ubiquitination level of PKA

Protein kinase A (PKA) plays an important role in cellular life activities. Recently, PKA was found to bind to the inhibitor of nuclear factor-kappaB (IκB), a key protein in the nuclear factor-kappaB (NF-κB) pathway, to form a complex involved in the regulation of inflammatory response. However, the role of PKA in the anti-inflammatory of goose fatty liver is still unclear. A total of 14 healthy 70-d-old male Lander geese were randomly divided into a control group and an overfeeding group. Inflammation level was analyzed by histopathological method in the liver. The mRNA and protein abundance of PKA and tumor necrosis factor-alpha (TNFα), as well as the ubiquitination level of PKA, were detected. Moreover, goose primary hepatocytes were cotreated with glucose, harringtonine, and carbobenzoxy-l-leucyl-l-leucyl-l-leucinal (MG132). Finally, the co-immunoprecipitated samples of PKA from the control and overfeeding group were used for protein mass spectrometry. The results showed that no difference in PKA mRNA expression was observed (P > 0.05), while the PKA protein level in the overfed group was significantly reduced (P < 0.05) when compared with the control group. The ubiquitination level of PKA was higher than that of the control group in fatty liver. The mRNA expression of PKA was elevated but protein abundance was reduced in goose primary hepatocytes with 200 mmol/L glucose treatment (P < 0.05). The PKA protein abundance was dramatically reduced in hepatocytes treated with harringtonine (P < 0.01) when compared with the glucose-supplemented group. Nevertheless, MG132 tended to alleviate the inhibitory effect of harringtonine on PKA protein abundance (P = 0.081). There was no significant difference in TNFα protein level among glucose-treated groups and control (P > 0.05). Protein mass spectrometry analysis showed that 29 and 76 interacting proteins of PKA were screened in goose normal and fatty liver, respectively. Validation showed that PKA interacted with the E3 ubiquitination ligases ring finger protein 135 (RNF135) and potassium channel modulatory factor 1 (KCMF1). In summary, glucose may inhibit the inflammatory response in goose fatty liver by increasing the ubiquitination level of PKA. Additionally, RNF135 and KCMF1 may be involved in the regulation of PKA ubiquitination level as E3 ubiquitination ligases.

Impact of Bioactive Compounds in the Management of Various Inflammatory Diseases

Inflammation is an individual's physiological response to a sequence of physical, chemical, or infectious stressors acting mainly to provide localized protection. Although inflammation is a protective and thus beneficial process, its excess or prolonged action can be harmful to the body. An increasing number of the population worldwide are changing their lifestyles, which leads to a rise in inflammatory diseases, such as atherosclerosis, angina pectoris, myocardial infarction, ulcerative colitis, cancer, and many more. Their treatment is based majorly on the pharmacological approach. However, natural products or bioactive compounds are of great significance in inflammation therapy because they show minimum side effects and maximum bioavailability. Therefore, it is critical to investigate bioactive substances that can modify target functions associated with oxidative stress defense and might be used to achieve various health benefits. This review accentuates the essence of bioactive chemicals used in the treatment of inflammation and other inflammatory illnesses. These bioactive compounds can be of any origin, such as plants, animals, bacteria, fungi, marine invertebrates, etc. Bioactive compounds derived from plant sources, such as glycyrrhizin, lignans, lycopene, resveratrol, indoles, and phenolic and polyphenolic compounds, work mainly by reducing oxidative stress and thereby preventing various inflammatory disorders. A large diversity of these anti-inflammatory bioactive compounds has also been discovered in marine environments, giving rise to an increase in the interest of various scientists in marine invertebrates and microbes. The vast diversity of microbes found in the marine environment represents an enormous supply to extract novel compounds, such as from bacteria, cyanobacteria, fungi, algae, microalgae, tiny invertebrates, etc. In the present review, an attempt has been made to summarize such novel bioactive compounds that help prevent inflammatory responses via different mechanisms of action.