Efficacy of Ginger (Zingiber officinale Roscoe) Extracts in Lowering Blood Glucose in Normal and High Fat Diet-induced Diabetic Rats

Abstract

Even though the hypoglycemic effect of various extracts of ginger had been delved into exhaustively the similar effect of the cooked form of the spice is yet to be ascertained. This is of vital importance since ginger is mostly consumed in cooked form in various dishes. Hence, the objective of this study is to determine the efficacy of raw and cooked ginger extracts in lowering blood glucose in normal and high fat diet-induced diabetic rats, an experimental model of Type 2 diabetes which is the most prevalent type of the disease. Male Albino rats (63) were divided into seven groups and designated thus: Group 1 – normal negative control, Group 2 – normal rats given raw ginger extract, Group 3 - normal rats given cooked ginger extract, Group 4 - diabetic control, Group 5 –diabetic rats given raw ginger extract, Group 6 – diabetic rats given cooked ginger extract and Group 7 – diabetic rats given Metformin. The diabetic groups were fed high fat diet for 12 weeks after which the 4 weeks extracts administration commenced Fasting blood glucose was determined before and after the 12 weeks diet introduction and at the 2nd and 4th weeks of extracts’ administration by using ACCU-CHEK Active Glucometer, Roche, Germany. ANOVA and Least Significant Difference were used for statistical analyses. There was no significant difference between. Raw ginger extract and Metformin normalized fasting blood glucose (FBG) in the diabetic rats because there was no significant difference (p<0.05) between these two groups and the normal negative control at 4 weeks extracts and drug administration. The cooked extract did not normalize the blood glucose but lowered it by 35%..The two extracts had similar hypoglycemic effect (24% reduction, p<0.05) in normal rats at 2 weeks and 4 weeks of administration. Hence raw ginger extract is as effective as Merformin in normalizing FBG but the cooked form may require a longer period to exert similar effect..Even though the extracts lowered the FBG below normal in normal rats this may not lead to clinically threatening hypoglycemia.