TITLE:
Antihyperglycemic Studies on the Leaf Extract and Active Fractions of Newbouldia laevis (Bignoniaceae)
AUTHORS:
Chinyelu C. Osigwe, Peter A. Akah, Chukwuemeka S. Nworu, Theophine C. Okoye, Michel K. Tchimene
KEYWORDS:
Newbouldia Laevis, Antihyperglycemic, Diabetes Mellitus, Blood Glucose, Alloxan, Hypoglycemia
JOURNAL NAME:
Pharmacology & Pharmacy,
Vol.6 No.11,
November
24,
2015
ABSTRACT: Optimal control of chronic hyperglycemia prevents both micro and macro
vascular complications—a leading cause of morbidity and mortality in diabetic
subjects. This study was undertaken to give credence to the traditional use of
Newbouldia laevis leaves in the treatment of diabetes mellitus (DM).
Dichloromethane-methanol (1:1) extract (DME) of N. laevis leaves was
prepared by cold maceration. Separation of DME into column chromatographic
fractions yielded the n-hexane fraction (HF), ethylacetate fraction (EF) and
methanol fraction (MF). The extract and fractions were evaluated for
antihyperglycemic activity in alloxanized diabetic rats. The results showed
that the oral administration of extract and fractions (250, 500, 1000 mg/kg)
caused a significant (P DME (dichloromethane/methanol
extract; 36.19%) > EF (ethylacetate fraction; 20.70%) > HF (n-hexane
fraction; 10.09. The methanol fraction, which showed the highest potency in
oral glucose tolerance test (OGTT), was further separated into column
chromatographic sub-fractions—F1, F2, F3 and F4 fractions. These sub-fractions
were evaluated for antihyperglycemic activity. Sub-fractions F1, F2 and F3 (1000 mg/kg) did produce significant (P > 0.05) reduction in blood
glucose level after 24 h. Sub-fraction F4 (50, 100, 200 mg/kg),
however caused a significant (P 4 (74.57%) was significantly (P Newbouldia laevis possess antihyperglycemic activities and can be the
basis for the folk use N. laevis in management of diabetes mellitus.