Histoprotective Effect of Aqueous Extract of Zobo (Hibiscus sabdariffa) Calyces on Alloxan-induced Pancreatic Damage in Adult Female Wistar Rats

Diabetes mellitus represents a persistent metabolic condition defined by elevated blood sugar, stemming from either the loss of insulin-producing beta cells or a diminished response to insulin. While conventional treatment like metformin manages glucose levels, they often fail to reverse underlying pancreatic damage. Consequently, there is an increasing interest in phytomedicines like Zobo (Hibiscus sabdariffa), known for its antioxidant-rich phytochemical profile, to aid in tissue regeneration. The present research evaluated the regenerative effects of H. sabdariffa aqueous extract on the pancreases of Wistar rats after inducing type 1 diabetes using alloxan monohydrate. Ten female rats were categorized into five experimental sets: normal control, diabetic control (alloxan 200 mg/kg), two Zobo extract cohorts (200 and 500 mg/kg), and a metformin-treated group (150 mg/kg). Successful induction of type 1 diabetes was verified by fasting glucose readings exceeding 200 mg/dL after single intraperitoneal administration. After a 7-day treatment period, pancreatic tissue was harvested and prepared for H&E histological evaluation. Histological results from the diabetic control group indicated disrupted acini and no pancreatic islets. In contrast, rats treated with H. sabdariffa extract showed dose-dependent structural recovery. The 500 mg/kg dose demonstrated significant restoration of pancreatic histoarchitecture, characterized by the presence of healthy islets and acinar cells, comparable to the regeneration observed in the metformin-treated group although the metformin-treated group appeared slightly better. The findings suggest that H. sabdariffa aqueous extract possesses potent restorative properties. By protecting beta cells from oxidative stress-induced apoptosis, it facilitates pancreatic regeneration, offering a promising, affordable, and natural adjunct therapy for diabetes management.

Key Words: alloxan, diabetes mellitus, Hibiscus sabdariffa, pancreatic regeneration, phytomedicine