| Abstract
| - A polyphenol extract from a Corbières (France) red wine (P, 200 mg/kg), ethanol (E, 1 mL/kg), or acombination of both (PE) was administered by daily gavage for 6 weeks to healthy control orstreptozotocin (60 mg/kg i.v.)-induced diabetic rats (180−200 g). Treatment groups included C or D(untreated control or diabetic) and CP, CE, or CPE (treated control) or DP, DE, or DPE (treateddiabetic). P treatment induced a reduction in body growth, food intake, and glycemia in both CP andDP groups. In DP, hyperglycemia was reduced when measured 1 h after daily treatment but not atsacrifice (no treatment on that day). The hyperglycemic response to the oral glucose tolerance test(OGTT) and plasma insulin at sacrifice were impaired similarly in DP and D groups. In contrast, inDE or DPE, body growth was partially restored while hyperglycemia was reduced both during treatmentand at sacrifice. In addition, hyperglycemia response to OGTT was reduced and plasma insulin washigher in DE or DPE than in D animals, indicating a long-term correction of diabetes in ethanol-treated animals. Morphometric studies showed that ethanol partially reversed the enlarging effect ofdiabetes on the mesenteric arterial system while the polyphenolic treatment enhanced it in the absenceof ethanol. In summary, our study shows that (i) a polyphenol extract from red wine (“used at apharmacological” dose) reduces glycemia and decreases food intake and body growth in diabeticand nondiabetic animals and (ii) ethanol (“nutritional” dose) administered alone or in combinationwith polyphenols is able to correct the diabetic state. Some of the effects of polyphenols were maskedby the effects of ethanol, notably in diabetic animals. Further studies will determine the effect of“nutritional” doses of polyphenols as well as their mechanism of action. Keywords: Red wine; polyphenols; alcohol; diabetes; streptozotocin rats; glycemia; insulin; levels;antidiabetic activity; microangiopathy
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