The Antioxidant Activities of Betula etnensis Rafin. Ethanolic Extract Exert Protective and Anti-diabetic Effects on Streptozotocin-Induced Diabetes in Rats

Abstract

Pathophysiological mechanisms correlating diabetes mellitus with associated complications are still not completely clear, even though oxidative stress seems to play a pivotal role. Literature data suggest that cell damages induced by hyperglycemia, although multifactorial, have a common pathway in oxidative/nitrosative stress. The present study evaluated the effects of Betula etnensis Raf. bark extract, a plant belonging to the Betulaceae family endemic to Sicily, on oxidative stress and in preventing and/or retarding diabetes-associated complications in streptozotocin diabetic rats treated with the extract at dose of 0.5 g/kg body weight per day for 28 consecutive days. The extract administration significant decreased food and water intake, fasting blood glucose, weight loss and polyuria, compared with untreated diabetic animals. Furthermore, oxidative stress markers particularly, lipid hydroperoxides (LOOH) and nitrite/nitrate levels, non-proteic thiol groups (RSH), γ-glutamyl-cysteine-synthetase (γ-GCS) activities and expression, heme oxygenase-1 (HO-1), endothelial and inducible nitric oxide synthases (i-NOS e-NOS) expression, significantly changed by streptozocin treatment, were markedly restored both in plasma and tissues together with nuclear sirtuins activity (Sirt1). Results suggested that B. etnensis bark alcoholic extract is able to counteract oxidative stress and to ameliorate some general parameters related to diabetes.

Antioxidant effect of ethanolic onion (Allium cepa) husk extract in ageing rats

“…Ageing is accompanied by a decrease in the activity of the AOS and the development of chronic oxidative stress. The concentration of GSH is one of the biomarkers of oxidative stress, since GSH is an important intracellular non-enzymatic endogenous antioxidant that can neutralise FRs and is a cofactor for many antioxidant enzymes ( Malfa et al, 2020 ). It was shown that the introduction of onion husk extract increased the concentration of GSH in the liver by 88.3%, but in the brain its elevation was not so noticeable and averaged only 34.0%.…”

“…Every year, a huge number of articles are published devoted to the study of the biological properties of various herbs, spices, fruits and vegetables for their further application in the food industry and in medicine ( Aremu et al, 2019 , Hariharapura et al, 2014 , Malfa et al, 2020 ). However, in recent years, the interest of scientists and producers has been directed towards the waste of the fruit and vegetable industry, due to the low cost and high content of biologically active substances ( Kupaeva and Kotenkova, 2019 ).…”

Antimicrobial, Antioxidant, and Cytotoxic Activities of Juglans regia L. Pellicle Extract

“…Radical scavenging activity of J. regia pellicle extract against stable DPPH• (2,2-diphenyl-2-picrylhydrazyl hydrate) was determined spectrophotometrically by the modified method described in Tenuta and collaborators and compared to Trolox (30 µM) as reference compound [ 80 ]. The scavenger effect of the pellicle extract on superoxide anion (SOD-like activity) was performed as previously reported [ 81 ]. Results are expressed as the percentage of inhibition of NADH oxidation, and SOD (80 mU) was used as a reference compound.…”

“…The polyphenols concentration detected was estimated as gallic acid equivalent (GE) and expressed in mg GE/g extract. The flavonoid content was measured using a colorimetric assay [ 81 ] and estimated as catechin equivalent (CE) and expressed in mg CE/g extract. Each result represents the mean ± S.D.…”

Phytochemical Analysis and Anti-Inflammatory and Anti-Osteoarthritic Bioactive Potential of Verbascum thapsus L. (Scrophulariaceae) Leaf Extract Evaluated in Two In Vitro Models of Inflammation and Osteoarthritis

“…The polyphenolic fingerprinting of the extract was defined by high-pressure liquid chromatography (HPLC). The analyses were performed as above described [ 34 ]. Briefly, samples were dissolved in 1 mL of dimethylformamide/water solution (9:1) with a final concentration of 10 mg/mL.…”