Hypoglycemic, Hypocholesterolemic, Anti-Anemic and Ocular-Protective Effects of an Aqueous Extract of the Rhizomes of Sansevieria liberica Gerome and Labroy (Agavaceae) on Alloxan Induced Diabetic Wistar Rats

The effects of an aqueous extract of the rhizomes of Sansevieria liberica on the haematology, plasma biochemistry and ocular indices of oxidative stress were investigated in alloxan induced diabetic rats. Diabetes mellitus was induced by injection of alloxan (80 mg/kg body weight), via the tail vein. The extract was administered orally at 100, 200 and 300 mg/kg (both to normal and diabetic rats), and metformin at 50 mg/kg. On gas chromatographic analysis of the extract, thirty nine known alkaloids (consisting mainly of 63.98% akuamidine, 33.63% voacangine and 1.26% echitamidine), tannic acid and -sitosterol were detected. Compared to test control, the treatment significantly (P<0.05) lowered in a dose dependent manner, ocular malondialdehyde content, atherogenic indices, lymphocyte and monocyte counts; and plasma levels of glucose, triglyceride, total-, very low density lipoprotein-, low density lipoprotein- and non-high density lipoprotein cholesterols, total and conjugated bilirubins, total protein, sodium, urea, blood urea nitrogen, as well as plasma activities of alkaline phosphatase, alanine and aspartate transaminases. However, the treatment significantly (P<0.05) increased packed cell volume, haemoglobin concentration, total white cell, neutrophil and eosinophil counts, mean cell volume, plasma levels of high density lipoprotein cholesterol, calcium, potassium, chloride and bicarbonate, and ocular vitamin C content and activities of catalase and superoxide dismutase. This study revealed the presence of pharmacologically active compounds in the rhizome extract. It showed the hypoglycemic, hypolipidemic, anti-anaemic, immunomodulatory, ocular-protective and hepato-renal toning potentials of the extract. All of these, highlights the cardioprotective and oculoprotective capacities of the rhizomes of Sansevieria liberica, and support their use in traditional health care practices for the management of diabetes mellitus.