Hypoglycaemic effect of total alkaloids extracted from Sambucus wightiana Wall. ex Wight & Arn. in streptozotocin-nicotinamide induced diabetic rats

 South African J Bot. 154, 330-355, 2023

Diabetes mellitus is the most prevalent metabolic disease, and almost 1200 plants are reported with hypoglycaemic potential. Some of these plants are scientifically proven for the hypoglycaemic and antidiabetic effects. This study was designed to assess the hypoglycaemic effect of Sambucus wightiana Wall. ex Wight & Arn. extract in streptozotocin-nicotinamide induced diabetic Wistar Albino rats. An acute toxicity study was performed to establish the safe dose of total alkaloids extracted from S. wightiana (TASW). TASW was administered orally (50 mg, 100 mg, and 200 mg/kg body weight per day) to diabetic rats for 21 days. Fasting blood glucose level was determined, along with other associated parameters that may fluctuate in diabetes, consisting of the lipid profile, body weight, serum liver marker enzymes and Hb level. The test groups that were administered TASW at three different doses showed a marked reduction in hyperglycaemia when compared to the control group. Moreover, body weight and food intake improved among test group animals. Administration of TASW also reduced the levels of triglycerides, cholesterol and LDL while increasing HDL and Hb levels. Serum liver enzyme activity is generally increased in diabetes, and this was reduced after dosing with TASW. The findings of this study elucidate that the total alkaloids extracted from S. wightiana are not toxic at the tested doses, and present potential hypoglycaemic activity.

Targeting of neuroinflammation by glibenclamide in Covid-19: old weapon from arsenal

 Inflammopharmacology, 31, 1-7 (2023)

In coronavirus disease 2019 (Covid-19) era, neuroinflammation may develop due to neuronal tropism of severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) and/or associated immune activation, cytokine storm, and psychological stress. SARS-CoV-2 infection and linked cytokine storm may cause blood–brain barrier (BBB) injury through which activated immune cells and SARS-CoV-2 can pass into the brain causing activation of glial cells with subsequent neuroinflammation. Different therapeutic regimens were suggested to alleviate Covid-19-induced neuroinflammation. Since glibenclamide has anti-inflammatory and neuroprotective effects, it could be effective in mitigation of SARS-CoV-2 infection-induced neuroinflammation. Glibenclamide is a second-generation drug from the sulfonylurea family, which acts by inhibiting the adenosine triphosphate (ATP)-sensitive K channel in the regulatory subunit of type 1 sulfonylurea receptor (SUR-1) in pancreatic β cells. Glibenclamide reduces neuroinflammation and associated BBB injury by inhibiting the nod-like receptor pyrin 3 (NLRP3) inflammasome, oxidative stress, and microglial activation. Therefore, glibenclamide through inhibition of NLRP3 inflammasome, microglial activation, and oxidative stress may attenuate SARS-CoV-2-mediated neuroinflammation.