Comparative effect of Rothmannia hispida leaves extract and protamine-zinc insulin on alloxaninduced diabetic rats

Abstract

Diabetes mellitus (DM) is a metabolic disorder resulting from a defect in insulin secretion, insulin action, or both.
Insulin and Rothmannia hispida are among the anti-diabetic agents. This study therefore sought to establish the
relative potency of insulin and R. hispida leaves extract in alloxan-induced diabetic rats. Four groups of 5 albino
Wistar rats each were made diabetic with alloxan (150 mg/kg), then treated with either extract (100 mg/kg) or insulin (1
unit) for 7 days or left untreated. The terminal blood glucose level of diabetic extract treated (DET) (4.40 ± 0.52 mmol/L)
and diabetic insulin treated (DIT) (4.10 ± 0.48 mmol/L) were significantly (P < 0.001) lower compared with diabetic
untreated (DUT) (22.00 ± 0.00 mmol/L). Terminal urine glucose was only present in DUT (42.60 ± 6.14 mmol/L) .
Terminal urine output was also significantly (P < 0.001) lower in DET (8.60 ± 1.17 ml) and DIT (8.80 ± 0.80 ml) compared
with DUT (44.00 ± 1.48 ml). The DUT and DIT were also observed to have negative growth rates (-4.86 and -0.29 g/day
respectively), whereas the controls and DET had positive growth rates (5.70 and 0.14 g/day respectively). Terminal
blood glucose levels and urine output were not significantly different between DET and DIT. Therefore, 100 mg/kg
body weight of the Rothmannia hispida leaves extract is equally as potent as 1 unit of protamine-zinc insulin as an
anti-diabetic agent.