Department of Human Nutrition, Foods and Exercise, Virginia Tech Blacksburg, VA 24061, USA.
Appl Physiol Nutr Metab. 2012 Jun;37(3):480-8. doi: 10.1139/h2012-005. Epub 2012 Apr 17.
While peripheral insulin resistance is common during obesity and aging in mice and people, the progression to type 2 diabetes (T2D) is largely due to loss of β-cell mass and function through apoptosis. We recently reported that genistein, a soy derived isoflavone, can improve glycemic control and β-cell function in insulin-deficient diabetic mice. However, whether it can prevent β-cell loss and diabetes in T2D mice is unknown. Our current study aimed to investigate the effect of dietary supplemented genistein in a nongenetic T2D mouse model. Nongenetic, middle-aged obese diabetic mice were generated by high fat diet and a low dose of streptozotocin injection. The effect of dietary supplementation of genistein on glycemic control and β-cell mass and function was determined. Dietary intake of genistein (250 mg·kg(-1) diet) improved hyperglycemia, glucose tolerance, and blood insulin level in obese diabetic mice, whereas it did not affect body weight gain, food intake, fat deposit, plasma lipid profile, and peripheral insulin sensitivity. Genistein increased the number of insulin-positive β-cell in islets, promoted islet β-cell survival, and preserved islet mass. In conclusion, dietary intake of genistein could prevent T2D via a direct protective action on β-cells without alteration of periphery insulin sensitivity.
虽然肥胖和衰老会导致小鼠和人类外周胰岛素抵抗，但 2 型糖尿病（T2D）的进展主要归因于β细胞数量和功能的凋亡性丧失。我们最近报道，大豆异黄酮染料木黄酮可改善胰岛素缺乏型糖尿病小鼠的血糖控制和β细胞功能。然而，其是否能预防 T2D 小鼠的β细胞损失和糖尿病尚不清楚。本研究旨在研究饮食补充染料木黄酮对非遗传 T2D 小鼠模型的影响。通过高脂肪饮食和小剂量链脲佐菌素注射，生成非遗传、中年肥胖糖尿病小鼠。确定饮食补充染料木黄酮对血糖控制和β细胞数量和功能的影响。饮食摄入染料木黄酮（250mg·kg(-1)饮食）可改善肥胖糖尿病小鼠的高血糖、葡萄糖耐量和血胰岛素水平，而对体重增加、食物摄入、脂肪沉积、血浆脂质谱和外周胰岛素敏感性没有影响。染料木黄酮增加了胰岛中胰岛素阳性β细胞的数量，促进了β细胞的存活，并保留了胰岛的质量。总之，饮食摄入染料木黄酮可通过直接保护β细胞而不改变外周胰岛素敏感性来预防 T2D。
