Glucotoxicity Induced Oxidative Stress and Inflammation In Vivo and In Vitro in Psammomys obesus: Involvement of Aqueous Extract of Brassica rapa rapifera

Inter-Varietal Variation in Phenolic Profile, Antioxidant, Anti-Inflammatory and Analgesic Activities of Two Brassica rapa Varieties: Influence on Pro-Inflammatory Mediators

The present research study aims to appraise the potential of polyphenol-rich extracts from two Brassica rapa varieties on antioxidant, anti-inflammatory and analgesic activities using carrageenan-induced paw edema model in rats. Methanol extracts of peels and pulps of Brassica rapa yellow root (BRYR) and Brassica rapa white root (BRWR) were prepared using the soxhlet extraction technique. All four extracts were analyzed by reversed-phase high-pressure liquid chromatography (RP-HPLC) for the polyphenols, and results showed that 10 phenolic acids and 4 flavonoids were detected. Gallic acid was the major phenolic acid (174.6-642.3 mg/100 g of dry plant material) while catechin was the major (34.45-358.5 mg/100 g of dry plant material) flavonoid detected in the extracts. The total phenolic contents (TPC) of BRYR peel, BRWR peel, BRYR pulp and BRWR pulp extracts were in the range of 1.21-5.01 mg/g of dry plant material, measured as GAE, whereas the total flavonoid contents (TFC) were found in the range of 0.90-3.95 mg/g of dry plant material, measured as QE. BRYR peel extract exhibited the best DPPH radical scavenging activity (IC50, 3.85 µg/mL) and reducing potential as compared with other extracts. The in vivo anti-inflammatory potential was assessed by carrageenan-induced rat paw edema, and the analgesic potential was investigated by a hot plate test. Suppression of biochemical inflammatory biomarkers including C-reactive protein (CRP), rheumatoid factor (RF) and tumor necrosis factor (TNF-α), and interleukin-6 (IL-6) concentration were also determined. Results showed that BRYR peel extracts reduced paw edema and suppressed the production of TNF-α, IL-6, CRP and RF most significantly, followed by BRWR peel, BRYR pulp and BRWR pulp extracts. In addition, histopathology observation also supports the anti-inflammatory effect of peel extracts as being greater than that of root pulp extracts. Moreover, it was observed that the analgesic effect of the root-peel extracts was also more pronounced as compared with root-pulp extracts. It can be concluded that BRYR peel extract has higher phenolic contents and showed higher suppression of TNF-α, IL-6, CRP and RF, with strong antioxidant, anti-inflammatory and analgesic effects.

Scolymus hispanicus (Golden Thistle) Ameliorates Hepatic Steatosis and Metabolic Syndrome by Reducing Lipid Accumulation, Oxidative Stress, and Inflammation in Rats under Hyperfatty Diet

Background

Lipotoxicity is characterized by a metabolic disturbance leading to the development of nonalcoholic fatty liver disease (NAFLD). Some medicinal plant extracts exert hepatoprotective activity by modulating oxidative stress, inflammation, and metabolic disorders. Scolymus hispanicus or the golden thistle can be considered an important natural source of antioxidants. In traditional medicine, the consumption of this plant is recommended for diseases of the liver and intestines.

Objective

In this study, we aimed to determine the effects of Scolymus hispanicus on a hyperfatty diet- (HFD-) induced metabolic disorders, oxidative stress, and inflammation.

Materials and Methods

Our experiment focused on the administration of an HFD (40%) in Rattus norvegicus for 2 months and treatment with the aqueous extract of Scolymus hispanicus at a rate of 100 mg/kg during the last eight days of experimentation. In this context, several aspects were studied: the evaluation of blood biochemical parameters, liver function such as lipids and glycogen, markers of oxidative stress (TBARS, carbonyl proteins, advanced oxidation proteins, catalase, and SOD) and inflammation (NO and NFkB), morphological study of hepatocytes in primary culture, and histological study of the liver.

Results

Lipotoxicity induced metabolic disorders, both serum and tissue. HFD induced an increase in the total lipids and a decrease in glycogen reserve and an alteration in the oxidant-antioxidant balance. HFD induced an increase in markers of liver damage, which resulted in NAFLD, confirmed by histological study and hepatocytes cell culture. Scolymus appears to have lipid-lowering, hypoglycemic, anti-inflammatory and antioxidant properties. It improved glucose tolerance and the condition of fatty liver disease.

Conclusion

Golden thistle improves glucose tolerance and hyperlipidemia and ameliorates hepatic steatosis by reducing oxidative stress, inflammation, and lipid accumulation. Its incorporation into a dietary program or as an aliment supplement would prevent hepatic complications associated with an HFD.

The Impact of Diabetes Mellitus in COVID-19: A Mechanistic Review of Molecular Interactions

The ongoing pandemic of COVID-19 is now the major issue in global health. Evidence implies that patients with diabetes are at a higher risk of severe disease or death due to COVID-19 than individuals without diabetes. However, the underlying mechanism for this differential effect in individuals with and without diabetes is not clearly understood. We have reviewed the pathophysiological pathways which may facilitate the entry of virus or an increase in its infectivity in host cells in the diabetic milieu. We suggest that the preexisting pathological pathways in patients with poorly controlled diabetes increase the risk of infectivity and are responsible for the higher levels of tissue injury and death in patients with diabetes.

Pharmacological modulation of the hydrogen sulfide (H2 S) system by dietary H2 S-donors: A novel promising strategy in the prevention and treatment of type 2 diabetes mellitus

Type 2 diabetes mellitus (T2DM) represents the most common age-related metabolic disorder, and its management is becoming both a health and economic issue worldwide. Moreover, chronic hyperglycemia represents one of the main risk factors for cardiovascular complications. In the last years, the emerging evidence about the role of the endogenous gasotransmitter hydrogen sulfide (H₂ S) in the pathogenesis and progression of T2DM led to increasing interest in the pharmacological modulation of endogenous "H₂ S-system". Indeed, H₂ S directly contributes to the homeostatic maintenance of blood glucose levels; moreover, it improves impaired angiogenesis and endothelial dysfunction under hyperglycemic conditions. Moreover, H₂ S promotes significant antioxidant, anti-inflammatory, and antiapoptotic effects, thus preventing hyperglycemia-induced vascular damage, diabetic nephropathy, and cardiomyopathy. Therefore, H₂ S-releasing molecules represent a promising strategy in both clinical management of T2DM and prevention of macro- and micro-vascular complications associated to hyperglycemia. Recently, growing attention has been focused on dietary organosulfur compounds. Among them, garlic polysulfides and isothiocyanates deriving from Brassicaceae have been recognized as H₂ S-donors of great pharmacological and nutraceutical interest. Therefore, a better understanding of the therapeutic potential of naturally occurring H₂ S-donors may pave the way to a more rational use of these nutraceuticals in the modulation of H₂ S homeostasis in T2DM.

Effects of Silymarin on Diabetes Mellitus Complications: A Review

Diabetes mellitus is a common metabolic disorder that is caused by a deficit in the production of (type 1) or response to (type 2) insulin. Diabetes mellitus is characterized by a state of chronic hyperglycemia and such symptoms as weight loss, thirst, polyuria, and blurred vision. These disturbances represent one of the major causes of morbidity and mortality nowadays, despite available treatments, such as insulin, insulin secretagogues, insulin sensitizers, and oral hypoglycemic agents. However, many efforts have been made to discover new drugs for diabetes treatment, including medicinal plant extracts. Silymarin is a powder extract of the seeds from Silybum marianum, a plant from the Asteraceae family. The major active ingredients include four isomers: silybin, isosilybin, silychristin, and silydianin. Silymarin is indicated for the treatment of hepatic disorders, such as cirrhosis, chronic hepatitis, and gallstones. Moreover, several studies of other pathologies, including diabetes, sepsis, osteoporosis, arthritis, hypercholesterolemia, cancer, viral infections, and Alzheimer's and Parkinson's diseases, have tested the effects of silymarin and reported promising results. This article reviews data from clinical, in vivo, and in vitro studies on the use of silymarin, with a focus on the complications of diabetes, including nephropathy, neuropathy, healing delays, oxidative stress, hepatotoxicity, and cardiomyopathy. Copyright © 2017 John Wiley & Sons, Ltd.