Nutritional, Antidiabetic and Antilipidemic Studies of Ethanolic Extract of P. tuber-regium in High-Fat-Streptozotocin-induced Diabetic Male Wistar Albino Rats

Abstract

Pleurotus tuber-regium, a nutritionally dense and bioactive-rich edible mushroom prevalent in West Africa, is gaining attention for its potential role in functional foods and complementary strategies for managing metabolic diseases. This study investigated the nutritional composition and some therapeutic potential of P. tuber-regium in high-fat diet and streptozotocin (STZ)-induced diabetic male Wistar albino rats. Proximate analysis was assayed using the methods described in AOAC, 2019, revealing the P. tuber-regium to be rich in carbohydrates (68.04%), crude protein (19.92%), and dietary fibre (5.44%), with low fat content (0.97%) and minimal moisture (2.20%), highlighting its suitability for hypocaloric diets. High-performance liquid chromatography (HPLC) analysis showed the presence of essential B-complex vitamins—thiamine (0.006 mg/g), riboflavin (0.003 mg/g), niacin (0.001 mg/g)—and vitamin C (0.008 mg/g), suggesting antioxidant and metabolic support roles. Mineral profiling via inductively coupled plasma-optical emission spectroscopy (ICP-OES) further confirmed the presence of micronutrients essential for enzymatic functions and metabolic homeostasis. Following a 9-week oral administration of P. tuber-regium ethanol extract at graded doses and metformin (200, 400, 800, 80 mg/kg respectively), diabetic rats demonstrated significant (p < 0.05) improvements in fasting blood glucose, lipid profile (triglycerides, total cholesterol, High Density Lipoprotein, Low Density Lippprotein), and pancreatic amylase activity. The Histomorphology assessments of pancreatic tissues also revealed restoration of islet architecture in extract-treated groups. Acute oral toxicity testing indicated no mortality or observable toxicological symptoms up to 6000 mg/kg, confirming the safety of P. tuber-regium extract. The results suggest that P. tuber-regium possesses promising antidiabetic and hypolipidemic properties, potentially mediated by its fibre content, micronutrients, and bioactive constituents. This supports its application as a nutraceutical in the dietary management of type 2 diabetes Mellitus. An extended mechanistic and clinical studies are warranted to elucidate the pathways involved and to validate translational applicability in human populations.