kpabio Elton1, Usip Lawrence, P. E.2, Bassey, G. F.3 and Bala, D. N.4
1Bluemoon Hospital, Uyo, Akwa Ibom State, Nigeria.
2Department of Animal and Environmental Biology, University of Uyo, Nigeria.
3Centre for Wetlands and Waste Management Studies, University of Uyo, Nigeria.
4Department of Pharmacognosy and Natural Medicine, Faculty of Pharmacy, University of Uyo, Nigeria.
ABSTRACT
BACKGROUND OF THE STUDY
Gmelina arborea is widely use in traditional medicine for treatment of many diseases. It is claimed to possess medicinal values including natural antioxidants for treatment of diabetes mellitus since this claimed has not been widely investigated scientifically, this motivated the choice of this study. The aim of this study was to evaluate the phytochemical screening, antidiabetic activities and haematological indices of the ethanolic leaves and stem barks extracts of Gmelina arborea in Alloxan induced diabetic albino white wistars rats.
METHODS
The phytochemical constituent of Gmelina arborea leaves and stem barks, fruit and seed were determined using standard methods. Gmelina arborea leaves and stem barks were air dried, pulvarized and extracted by maceration in line with standard procedures. Alloxan mohydrate and Gilbenclamine were used as diabetes inducted drugs and standard drug respectively. Diabetes was induced by single peritoneal injection of alloxan at 150 mg/kg body weight. The leaves and stem barks and extracts of Gmelina arborea were evaluated for acute toxicity and haematological indices using standard procedures.
RESULTS
The phytochemical screening results showed that the leaves extracts contains saponins and flavonoids in high concentration, alkaloids, tannins, anthraquinones and cardiac glycosides in moderate amount. Similar compounds were found in the stem bark which exceptionally contain Keller Killan.
The medium lethal doses LD50 of both extracts were higher than 4000 mg/kg body weight, indicating the extracts are not toxic under the observable condition. The leaves extract shows no reduction in glucose level at 200 mg/kg body weight, from zero hour to the sixth hour. However at 400 mg/kg body weight, glucose level reduces from 257.33 to 215.33 mmol/l at 600 mg/kg body weight (252.66 to 213.00 mmol/l) at 800 mg/kg body weight (257.66 to 200.33 mmol/l) compared to the standard glibeclamine (252.00 to 183.00 mmol/l). Similarly in the stem bark extracts there was no reduction in glucose level at 200mg/kg body weight but there was a significant reduction in glucose level at 400mg/kg weight from 263.33 to 218.67 mmol/l, at 600mg/kg body weight (264.00 to 175.00 mmol/l) and at 800 mg/kg body weight (263.66 to 171.66 mmol/l) compared to the standard glibeclamine 256 to 161.00 mmol/l. The anti diabetic activities was observed to be highest at 800 mg/kg body weight for leaves (200.33 ± 0.67) and stem barks (171.66 ±8.37). In haematological indices, the leaves extracts showed significant increase at 800 mg/ml; haemoglobin concentration 15.0 g/dl, pack cell volume 40%, red blood cell 4.5 x 106 and white blood cell count 10905 per mm3, while the stem barks equally increases at 800 mg/mL, haemoglobin concentration 16.0 g/dl packed cell volume 42%, red blood cell count 7.5 x 106 and white blood cell count 10000 per m3.
CONCLUSIONThis study indicates that the leaves and stem bark of Gmelina arborea are endowed with significant anti-diabetic activities and haematological indices that deserve further purification to isolate the bioactive compound. It is presumable reduction in glucose level is due to the presence of polyphenolic compounds and antioxidants especially flavonoids and saponins. Gmelina arborea leaves and stem barks extract possess a great potential for treatment of diabetes. The future of using the leaves and stem barks extracts of Gmelina arborea in development of diabetic remedy and drug is very promising.