衰老过程中的胰岛素抵抗与β细胞功能障碍：膳食碳水化合物的重要性

Insulin resistance and beta-cell dysfunction in aging: the importance of dietary carbohydrate.

作者信息

Chen M, Bergman R N, Porte D

机构信息

Veterans Administration Medical Center, Seattle, Washington.

出版信息

J Clin Endocrinol Metab. 1988 Nov;67(5):951-7. doi: 10.1210/jcem-67-5-951.

DOI:10.1210/jcem-67-5-951

PMID:3053750

Abstract

Aging is associated with a progressive decrease in glucose tolerance. This decrease is associated with insulin resistance and beta-cell dysfunction. This study was performed to evaluate the possible role of dietary factors in the glucose intolerance of aging. Two groups of men were studied: one young (Y; n = 8; age range, 18-36 yr) and one elderly (E; n = 10; age range, 65-82 yr). Frequently sampled iv glucose tolerance tests were performed in random order: 1) during ad libitum home dietary conditions; 2) after a 3- to 5-day regimen of very high (85%) carbohydrate intake; and 3) after a 3- to 5-day regimen of low (30%) carbohydrate intake (Y only). From the frequently sampled iv glucose tolerance test data, we calculated the glucose disappearance rate (Kg) and metabolic parameters according to the minimal model method, including the insulin sensitivity index (S1) and the first and second phase beta-cell responsivity to glucose (phi 1 and phi 2). The elderly men, while eating an ad libitum diet, were less tolerant to glucose than the young [mean Kg: E = 1.5 +/- 0.2% (+/- SE) min-1; Y = 2.3 +/- 0.3% min-1; P less than 0.025], had relative insulin resistance (mean Si: Y = 6.1 +/- 1.1; E = 2.4 +/- 0.7 min-1 10(-4)/(microU/mL) [0.85 +/- 0.15 vs. 0.33 +/- 0.10 min-1 10(-4)/(pmol/L)]; P less than 0.01), and lesser second phase beta-cell responsiveness to glucose (mean phi 2: Y = 18.5 +/- 3.6; E = 8.7 +/- 2.7 (microU/mL).min-2/(mg/dL) [2390 +/- 465 vs. 1120 +/- 349 (pmol/L).min-2/(mmol/L)]; P less than 0.05). A maximum improvement in Kg and S1 occurred at 41% carbohydrate feeding in the young men, whereas in the elderly men there was a significant increase in both of these parameters while eating the very high (85%) carbohydrate diet. Thus, the difference in glucose tolerance between groups was corrected by the very high carbohydrate diet (mean Kg: Y = 2.2 +/- 0.2%; E = 2.0 +/- 0.3%/min; P greater than 0.05), as was the age-related difference in insulin sensitivity (mean S1: Y = 5.6 +/- 1.2; E = 4.4 +/- 1.3 min-1 10(-4)/(microU/mL) [0.78 +/- 0.17 vs. 0.61 +/- 0.18 min-1 10(-4)/(pmol/L)]; P greater than 0.5).(ABSTRACT TRUNCATED AT 400 WORDS)

摘要

衰老与葡萄糖耐量的逐渐下降有关。这种下降与胰岛素抵抗和β细胞功能障碍有关。本研究旨在评估饮食因素在衰老所致葡萄糖不耐受中可能发挥的作用。研究了两组男性：一组为年轻人（Y组；n = 8；年龄范围18 - 36岁），另一组为老年人（E组；n = 10；年龄范围65 - 82岁）。以随机顺序进行多次采样的静脉葡萄糖耐量试验：1）在随意在家饮食条件下；2）在进行3至5天的高碳水化合物（85%）摄入方案后；3）在进行3至5天的低碳水化合物（30%）摄入方案后（仅针对Y组）。根据多次采样的静脉葡萄糖耐量试验数据，我们按照最小模型法计算葡萄糖消失率（Kg）和代谢参数，包括胰岛素敏感性指数（S1）以及β细胞对葡萄糖的第一和第二阶段反应性（phi 1和phi 2）。在随意饮食时，老年男性对葡萄糖的耐受性低于年轻男性[平均Kg：E组 = 1.5 ± 0.2%（±SE）min⁻¹；Y组 = 2.3 ± 0.3% min⁻¹；P < 0.025]，存在相对胰岛素抵抗（平均Si：Y组 = 6.1 ± 1.1；E组 = 2.4 ± 0.7 min⁻¹ 10⁻⁴/(μU/mL) [0.85 ± 0.15 vs. 0.33 ± 0.10 min⁻¹ 10⁻⁴/(pmol/L)]；P < 0.01），且β细胞对葡萄糖的第二阶段反应性较低（平均phi 2：Y组 = 18.5 ± 3.6；E组 = 8.7 ± 2.7 (μU/mL).min⁻²/(mg/dL) [2390 ± 465 vs. 1120 ± 349 (pmol/L).min⁻²/(mmol/L)]；P < 0.05）。年轻男性在摄入41%碳水化合物时，Kg和S1出现最大改善，而老年男性在摄入高碳水化合物（85%）饮食时，这两个参数均显著增加。因此，高碳水化合物饮食纠正了两组之间的葡萄糖耐量差异（平均Kg：Y组 = 2.2 ± 0.2%；E组 = 2.0 ± 0.3%/min；P > 0.05），以及与年龄相关的胰岛素敏感性差异（平均S1：Y组 = 5.6 ± 1.2；E组 = 4.4 ± 1.3 min⁻¹ 10⁻⁴/(μU/mL) [0.78 ± 0.17 vs. 0.61 ± 0.18 min⁻¹ 10⁻⁴/(pmol/L)]；P > 0.5）。（摘要截断于400字）