Department of Food Science and Nutrition, University of Minnesota, 1334 Eckles Avenue, St Paul, MN 55108, USA.
Br J Nutr. 2012 Jan;107(2):192-201. doi: 10.1017/S0007114511002741. Epub 2011 Jun 30.
Epidemiological evidence suggests that whole grain intake is associated with reduced risk of type 2 diabetes. However, studies of individual whole grains on the prevention of type 2 diabetes are lacking. The objective of the present study was to examine the effect of different whole grains on type 2 diabetes in an animal model of type 2 diabetes, the Goto-Kakisaki (GK) rat. GK rats were fed either a basal diet or a whole grain-containing diet for 5 months. Whole grain diets contained 65 % whole grain flours of wheat, barley, oats or maize. After 2 months of feeding, fasting plasma glucose concentrations were lower in the wheat, barley and oats groups, compared with the basal group, whereas glycated Hb was significantly greater in the wheat group compared with other groups. Feeding of whole barley and maize increased plasma C-peptide concentrations compared with whole wheat at 2 months. There was a trend in the improvement of insulin resistance with a consumption of barley and oats diets at 2 months (P = 0·06) compared with the basal diet. Oxidative stress markers, urinary thiobarbituric acid-reactive substances and 8-isoprostane, did not improve with whole grain intake at 2 months. At 5 months, whole grain diets did not differ from the basal diet in glycaemic control, insulin secretion, oxidative stress and preservation of pancreatic β-cell mass. These results suggest that the consumption of whole grains may offer modest benefit early in the development of type 2 diabetes, but this benefit is lost with further development of the disease.
流行病学证据表明，全谷物的摄入与 2 型糖尿病风险的降低有关。然而，关于单一全谷物对 2 型糖尿病预防作用的研究还很缺乏。本研究旨在通过 2 型糖尿病动物模型（GK 大鼠）研究不同全谷物对 2 型糖尿病的影响。GK 大鼠给予基础饮食或含全谷物饮食喂养 5 个月。全谷物饮食包含 65%的全麦粉，来源于小麦、大麦、燕麦或玉米。喂养 2 个月后，与基础组相比，小麦、大麦和燕麦组大鼠的空腹血糖浓度更低，而小麦组大鼠的糖化血红蛋白显著高于其他组。与全小麦相比，喂养全大麦和全玉米能在 2 个月时增加血浆 C 肽浓度。与基础饮食相比，喂养大麦和燕麦饮食在 2 个月时改善胰岛素抵抗有一定趋势（P=0.06）。氧化应激标志物，尿硫代巴比妥酸反应物质和 8-异前列腺素在 2 个月时并没有随着全谷物的摄入而改善。5 个月时，全谷物饮食在血糖控制、胰岛素分泌、氧化应激和胰腺β细胞质量的保留方面与基础饮食没有差异。这些结果表明，在 2 型糖尿病早期，全谷物的摄入可能会带来适度的益处，但随着疾病的进一步发展，这种益处会消失。
