Jasmine green tea improves glucose homeostasis and antioxidant activities with concomitant hypolipidemic activity in type 2 diabetic rats

Jasmine green tea (JGT) is traditionally consumed for its health benefits, however its mineral composition, nanoparticles characteristics, and antidiabetic mechanisms remain poorly understood despite of its known antioxidant properties. In this study, we evaluated the therapeutic effects of JGT infusion on glucose homeostasis, lipid metabolism, and oxidative stress in a male Sprague-Dawley rat model of type 2 diabetes (T2D) induced by fructose and streptozotocin. Diabetic rats allocated to the JGT treatment groups were administered a low-dose (150 mg/kg) or a high-dose (300 mg/kg) JGT infusion by an oral gavage, five times per week over a four-week period. Phytochemical analysis was performed using high-performance liquid chromatography (HPLC), and mineral content was determined through inductively coupled plasma optical emission spectrometry (ICP-OES). Nanoparticles within the JGT infusion were characterized by using transmission electron microscopy (TEM) and dynamic light scattering (DLS). JGT administration significantly (p < 0.05) reduced fasting blood glucose, improved glucose tolerance, and enhanced pancreatic β-cell function in T2D rats. It also ameliorated lipid abnormalities by reducing total cholesterol, triglycerides, and LDL-c, and restored liver glycogen and improved pancreatic islet morphology. Serum markers of hepatic, renal, and cardiac injury (ALT, AST, ALP, urea, UA, CK-MB) were significantly ameliorated. Insulin sensitivity was improved, as reflected by decreased HOMA-IR and fructosamine, and increased HOMA-β and serum insulin levels. Antioxidant defense was enhanced in the pancreas, liver, kidneys, and heart through elevated SOD, CAT, GSH, and GR activities, and reduced MDA content. These findings underscore the therapeutic potential of JGT for managing T2D and its associated complications.