Effect of guava (Psidium guajava Linn.) leaf soluble solids on glucose metabolism in type 2 diabetic rats.
This study investigated the effect of aqueous and ethanol soluble solid extracts of guava (Psidium guajava Linn.) leaves on hypoglycemia and glucose metabolism in type 2 diabetic rats. Low-dose streptozotocin (STZ) and nicotinamide were injected into Sprague-Dawley (SD) rats to induce type 2 diabetes. Acute and long-term feeding tests were carried out, and an oral glucose tolerance test (OGTT) to follow the changes in plasma glucose and insulin levels was performed to evaluate the antihyperglycemic effect of guava leaf extracts in diabetic rats.The results of acute and long-term feeding tests showed a significant reduction in the blood sugar level in diabetic rats fed with either the aqueous or ethanol extract of guava leaves (p < 0.05). Long-term administration of guava leaf extracts increased the plasma insulin level and glucose utilization in diabetic rats. The results also indicated that the activities of hepatic hexokinase, phosphofructokinase and glucose-6-phosphate dehydrogenase in diabetic rats fed with aqueous extracts were higher than in the normal diabetic group (p < 0.05). On the other hand, diabetic rats treated with the ethanol extract raised the activities of hepatic hexokinase and glucose-6-phosphate dehydrogenase (p < 0.05) only. The experiments provided evidence to support the antihyperglycemic effect of guava leaf extract and the health function of guava leaves against type 2 diabetes.
Shen
Szu-Chuan
SC
Department of Medical Nutrition, I-Shou University, No.1, Sec. 1, Syuecheng Road, Dashu Township, Kaohsiung County 84001, Taiwan. scs@isu.edu.tw
Cheng
Fang-Chi
FC
Wu
Ning-Jung
NJ
D000818:Animals; D001786:Blood Glucose / Q000187:drug effects / Q000378:metabolism*; D003921:Diabetes Mellitus, Experimental / Q000139:chemically induced / Q000188:drug therapy*; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy*; D005951:Glucose Tolerance Test; D019298:Glucose-6-Phosphate / Q000378:metabolism; D006593:Hexokinase / Q000378:metabolism; D006943:Hyperglycemia / Q000188:drug therapy; D007004:Hypoglycemic Agents / Q000627:therapeutic use*; D007328:Insulin / Q000097:blood; D008099:Liver / Q000201:enzymology; D009536:Niacinamide / Q000494:pharmacology; D025501:Phosphofructokinase-1, Liver Type / Q000378:metabolism; D008517:Phytotherapy; D010936:Plant Extracts / Q000627:therapeutic use*; D018515:Plant Leaves / Q000737:chemistry; D031647:Psidium / Q000737:chemistry*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013311:Streptozocin / Q000494:pharmacology
D001786:Blood Glucose; D007004:Hypoglycemic Agents; D007328:Insulin; D010936:Plant Extracts; D009536:Niacinamide; D019298:Glucose-6-Phosphate; D013311:Streptozocin; D025501:Phosphofructokinase-1, Liver Type; D006593:Hexokinase