The Haematological Effects of Oleanolic Acid in Streptozotocin-Induced Diabetic Rats: Effects on Selected Markers.

BACKGROUND: Sustained hyperglycaemia leads to the development of haematological alterations which, if left untreated, is associated with cardiovascular complications. Insulin is the mainstay drug in type 1 diabetes mellitus (T1D); however, the use of insulin is associated with haematological alterations that could further worsen cardiovascular complications. Therefore, the aim of the study was to investigate the haematological effects of oleanolic acid (OA) in streptozotocin- (STZ-) induced diabetic rats. METHODS: The animals were separated into five groups; the nondiabetic group (ND), the diabetic control group (DC), and the treatment groups of insulin (170 µg/kg, s.c), metformin (500 mg/kg, p.o), and OA (80 mg/kg, p.o). OA was administered orally twice a day. Thereafter, the animals were sacrificed, and blood and tissues were collected for haematological, hormonal, and oxidative status analysis. RESULTS: Untreated diabetic rats exhibited hyperglycaemia, elevated glycated haemoglobin (HbA1c), oxidative stress, and a reduced erythropoietin (EPO) concentration when compared to ND rats. However, administration of OA attenuated hyperglycaemia, HbA1c, and EPO concentrations compared to DC rats. The reduction of blood glucose concentration, HbA1c, and improved EPO concentrations was further associated with a notable increase in red blood cell (RBC) count and other RBC indices. We also observed an increase in the antioxidant status of the RBCs with a concomitant decrease in oxidative stress. CONCLUSION: These findings suggest that OA improves diabetes-induced haematological changes caused by hyperglycaemia and attenuates the progression of cardiovascular complications in DM individuals.

The effects of Momordica balsamina methanolic extract on haematological function in streptozotocin-induced diabetic rats: Effects on selected markers.

BACKGROUND: Chronic hyperglycaemia-induced haematological changes increase the risk of cardiovascular complications in diabetic patients. The administration of insulin injection as a bolus is accompanied with increased blood viscosity, which is not recommended for patients with congestive heart failure. Momordica balsamina methanolic extract (MB) has previously been shown to possess anti-hyperglycaemic and renal dysfunction ameliorative effects; however, the haematological effects of MB have not been shown. The current study therefore, investigated the short-term effects MB on selected haematological parameters in streptozotocin (STZ)-induced diabetic rats. METHODS: Briefly, the air-dried Momordica balsamina leaves were sequentially extracted with methanol to yield a methanolic extract. STZ-induced diabetic rats were divided into untreated and treated groups with insulin (170 µg kg-1 s.c.) and metformin (500 mg kg-1 p.o.) MB (250 mg kg-1 p.o.). MB was administered twice daily for the 5-week experimental period. Blood glucose concentration was monitored weekly. Animals were sacrificed terminally. Blood and kidneys were collected for haematological and biochemical analysis respectively. RESULTS: Treatment with MB significantly decreased blood glucose concentration and improved erythropoietin secretion, thus significantly increasing red blood cell production in treated diabetic animals by comparison to untreated animals. MB also significantly improved haemoglobin concentrations and moderately increased erythrocyte indices specifically, mean corpuscular volume (MCV), mean corpuscular haemoglobin concentration (MCHC) and mean corpuscular haemoglobin (MCH) to no significance by comparison to untreated diabetic animals. MB treatment decreased the oxidative stress evoked by the induction of diabetes while improving the antioxidant status of treated animals by comparison to untreated animals respectively. CONCLUSIONS: Administration of Momordica balsamina methanolic extract protects against some injurious haematological changes induced by hyperglycaemia, which may reduce the risks of cardiovascular complications.