Deciphering the Effect of Tetrapleura tetraptera Saponins on Carbohydrate Metabolizing Enzymes in STZ-Diabetic Wistar Rats: A Gene Expression Study

Tetrapleura tetraptera (Taub), widely utilized in traditional African medicine to manage various ailments, including diabetes, is a rich source of bioactive and therapeutic compounds, especially saponins. This study assessed saponins from T. tetraptera root bark for modulating carbohydrate-metabolizing enzymes in STZ-induced diabetic male Wistar rats. The genes evaluated were glucokinase, phosphofructokinase-1 (PFK-1), pyruvate kinase, glucose-6-phosphatase (G-6-Pase), fructose-1,6-bisphosphatase (F-1,6-BPase), fructose-2,6-bisphosphatase (F-2,6-BPase), phosphoenolpyruvate carboxykinase (PEPCK), and glucose-6-phosphate dehydrogenase (G-6-PDH). Forty-two (42) male Wistar rats were allocated into six (6) groups of seven (7) rats each. Diabetic treated rats (Group 3 - positive control) were administered metformin at 100 mg/kg, while Groups 4, 5, and 6 received T. tetraptera saponins (TTS) at 10, 20, and 40 mg/kg, respectively, via oral gavage for 12 weeks. The untreated group (Group 2 - negative control) was investigated simultaneously and compared to the normal control (Group 1). The study demonstrates the hypoglycemic potential of TTS in promoting glucose utilization via major carbohydrate pathways through the upregulation of key glycolytic genes (glucokinase, PFK-1) and pentose phosphate (G-6-PDH) pathway genes, along with the downregulation of key gluconeogenic genes (F-1,6-BPase, PEPCK) in STZ-induced diabetic rats. These findings suggest that TTS may modulate hyperglycaemia by enhancing glucose utilization and inhibiting gluconeogenesis.