ARS | Publication request: Augmented insulin effects on plasma glucose by cranberry procyanidins in streptozotocin-induced diabetic rats

Submitted to: Federation of American Societies for Experimental Biology Conference
Publication Type: Abstract Only
Publication Acceptance Date: March 15, 2010
Publication Date: April 12, 2010
Citation: Prior, R.L., Wilkes, S., Khanal, R., Howard, L., Rogers, T.J. 2010. Augmented insulin effects on plasma glucose by cranberry procyanidins in streptozotocin-induced diabetic rats [abstract]. Federation of American Societies for Experimental Biology Journal 24:209.2.

Technical Abstract: Objectives of this study were to determine if cranberry proanthocyanidins (CPACs) had an antihyperglycemic effect in the presence or absence of insulin in male diabetic Sprague-Dawley rats. Rats (approximately 250 g)(n=6-10/ trt) were given a single intraperitoneal (ip) injection of freshly prepared streptozotocin (STZ) at a dose of 70 mg/kg in 50 mM citrate buffer (pH 4.5). Diabetic animals with hyperglycemia greater than 400 mg/dL on day 7 after STZ injection were used. Treatments included: 1) Oral gavage of tap water; 2) Oral gavage of CPACs in aqueous solution (250 mg/kg body weight); 3) Oral gavage of tap water plus insulin - 9 nmole/animal ip; 4) Oral gavage of CPACs (250 mg/kg body weight) plus insulin - 1.26 nmole/animal ip; 5.) Insulin given ip at a dose of 1.26 nmole/animal. Blood samples were collected by tail bleeding, and glucose measured at 0, 30, 60, 90, 120, 150, 210, and 270 min. CPACs did not alter glucose levels compared to water. CPACs plus the low dose of insulin potentiated the insulin effect in lowering glucose equivalent to the high dose of insulin. Area under the curve for blood glucose change following treatment was -22486 +/- 6426; -21219 +/- 7322; -9928 +/- 10262; -89991 +/- 4604; -65605 +/- 11463; for treatments 1, 2, 3, 4, and 5 respectively. Cranberry derived procyanidins had an additive antihyperglycemic effect in the presence of a low insulin dose, but not in the absence of insulin.