Clinacanthus nutans leaf extract reduces pancreatic β-cell apoptosis by inhibiting JNK activation and modulating oxidative stress and inflammation in streptozotocin-induced diabetic rats

Background: Controlling apoptosis induced by oxidative stress in pancreatic β-cells provides promising strategies for preventing and treating diabetes. Clinacanthus nutans leaves possess bioactive constituents with potential antioxidant and anti-diabetic properties. Aim: This study aimed to investigate the molecular mechanisms by which C. nutans extract protects pancreatic β-cells from apoptotic damage in streptozotocin (STZ)-induced diabetic rats. Methods: Diabetes was induced in male Wistar rats by intraperitoneal injection of 45 mg/kg STZ, followed by 28 days of treatment with C. nutans leaf extract and Glibenclamide as the standard drug. At the end of the study, blood samples were collected to measure glucose levels, oxidative stress markers, and inflammation. Pancreatic tissue was stained immunohistochemically to detect c-Jun N-terminal kinase (JNK) and Caspase-3 expression. Results: The administration of C. nutans leaf extract to diabetic rats significantly reduced fasting blood glucose, malondialdehyde, and tumor necrosis factor-α levels, while concurrently enhancing the activity of superoxide dismutase. The immunohistochemical studies revealed a decrease in the expression of JNK and caspase-3 in the pancreatic islets of diabetic rats. Conclusion: Clinacanthus nutans exhibits the potential to protect pancreatic β-cells from apoptosis by suppressing oxidative stress and inflammation.