The insulin tolerance test in morbidly obese patients undergoing bariatric surgery.

OBJECTIVE: To assess the effect of massive weight loss in relation to insulin resistance and its correlation to changes in glycemic homeostasis and lipid profile in severely obese patients. RESEARCH METHODS AND PROCEDURES: A prospective clinical intervention study was carried out with 31 morbidly obese women (body mass index: 54.2 +/- 8.8 kg/m(2)) divided into three groups according to their glucose tolerance test: 14 normal, 8 impaired glucose tolerance, and 9 type 2 diabetes. All subjects underwent an insulin tolerance test with intravenous bolus of 0.1 U insulin/kg body weight before silastic ring vertical gastroplasty Roux-en-Y gastric bypass surgery, and again at 2, 4, 6, and 12 months postoperatively. Fasting plasma glucose, hemoglobin A1c, and lipid profile were also evaluated. RESULTS: A reduction of 68 +/- 15% in initial excess body weight was evident within 1 year. Along with weight loss, the following statistically significant changes were found: an increase in the insulin-sensitivity index (Kitt) and a decrease in fasting plasma glucose and hemoglobin A1c, most notably in the type 2 diabetes group. An overall improvement in lipid profile was observed in all three groups. DISCUSSION: Bariatric surgery was an effective therapeutic approach for these obese patients because it reduced both weight and insulin resistance, along with improving metabolic parameters. Significant correlations were found between insulin resistance and metabolic improvements. Weight loss after bariatric surgery induced an improvement in metabolic fitness, related to the reduction in insulin resistance over a range of glucose tolerance statuses from normal to diabetic.     

Alcohol consumption and insulin resistance syndrome parameters: associations and evolutions in a longitudinal analysis of the French DESIR cohort

PURPOSE: To determine the effects of average alcohol consumption and changes in alcohol intake on the insulin resistance syndrome parameters in a 3-year follow-up study. METHODS: Longitudinal study of 1856 and 1529 alcohol drinking men and women in the French DESIR study (Data from an Epidemiological Study on the Insulin Resistance syndrome), aged 30 to 64 years. RESULTS: In men, fasting glucose, body mass index, waist circumference, systolic blood pressure, and HDL-cholesterol were positively associated with average alcohol consumption while there was no association with insulin or triglycerides concentrations. A change in alcohol intake was positively associated with HDL-cholesterol concentration and systolic blood pressure at follow-up. These effects of alcohol could not be attributed specifically to the intake of wine. In women, while the alcohol HDL-cholesterol relation was similar to that found in the men, the only significant effect of average alcohol intake was an increase in systolic blood pressure, with a spurious decrease in blood pressure related to a 3-year increase in alcohol intake. CONCLUSIONS: Alcohol only provided a beneficial effect on HDL-cholesterol. The beneficial effect seen by other authors of moderate alcohol drinking on diabetes and cardiovascular risk may be due to effects on parameters other than those included in the current definitions of the insulin resistance syndrome.     

长期酒精作用对大鼠骨骼肌PI-3K表达的影响

目的:研究酒精长期作用下对大鼠骨骼肌磷脂酰肌醇3激酶(phosphatidylinositol 3-kinase,PI-3K)调节亚基p85αmRNA及蛋白水平表达的影响,探讨酒精引起胰岛素抵抗的相关分子机制。方法:清洁级Wistar大鼠80只(雌雄各半),按体重随机分为对照组和低、中、高剂量组,分别给予蒸馏水以及10%、20%、33%酒精溶液,灌胃剂量为10ml/(kg·bw·d)。第19周末,断头处死大鼠,测定空腹血糖和血胰岛素,计算HOMA胰岛素抵抗指数(HOMA-IR)。分离骨骼肌,通过RT-PCR和Westernblot方法测定p85αmRNA和蛋白表达水平。结果:雄性大鼠高剂量组空腹血糖,低、中剂量组空腹胰岛素水平升高,各酒精剂量组HOMA-IR指数均升高。p85αmRNA及蛋白表达水平表现为随着酒精剂量的增加先升高后降低;雌性大鼠高剂量组空腹血糖升高、空腹血胰岛素下降,p85αmRNA及蛋白的表达在中、高剂量组降低。各剂量组HOMA-IR指数与对照组比较差异无显著性。结论:长期摄入过量酒精可以造成骨骼肌组织p85α表达的改变,这可能是酒精降低胰岛素敏感性,引起胰岛素抵抗的分子机制。     

Lipid profile in the severely obese: changes with weight loss after lap-band surgery

OBJECTIVE: To characterize dyslipidemia before and after weight loss in the severely obese. RESEARCH METHODS AND PROCEDURES: Five hundred fifteen subjects who had Lap-Band surgery were followed with yearly conventional lipid profiles for up to 4 years. Preoperative data were collected from the most recent 381 subjects, and predictors of dyslipidemia were sought. One hundred seventy-one subjects completed a 1-year review, providing data to assess predictors of change in lipids. RESULTS: Favorable changes in fasting triglycerides (TG), high-density lipoprotein-cholesterol (HDL-C), and total cholesterol (TC):HDL-C ratio occurred within 1 year. All improvements were maintained up to 4 years. Male gender, central obesity, elevated fasting glucose, and insulin resistance were associated with less favorable lipid levels. Fasting plasma glucose best predicted TG (r = 0.46, p < 0.001), whereas insulin sensitivity using the homeostatic model assessment (HOMA %S) correlated best with the HDL-C (r =0.34, p < 0.001). Higher preoperative fasting glucose best predicted the decrease in TG; improved HOMA %S with weight loss correlated best with HDL-C. The extent of weight loss had limited influence on lipid changes. However, low preoperative HOMA %S was associated with lower weight loss. Greater weight loss was associated with more favorable lipid measures after controlling for preoperative HOMA %S. DISCUSSION: Dyslipidemia of obesity is related to weight distribution, insulin sensitivity, and impaired glucose tolerance. Improvement with weight loss is related to the decrease in fasting glucose, improvement in insulin sensitivity, and the extent of weight lost. Improvement in dyslipidemia is sustained with long-term weight loss.     

Phylloquinone intake, insulin sensitivity, and glycemic status in men and women

BACKGROUND: Limited evidence suggests that vitamin K may have a beneficial role in glucose homeostasis. No observational data exist on the associations between vitamin K intake and insulin sensitivity. OBJECTIVE: We aimed to examine associations between vitamin K intake and measures of insulin sensitivity and glycemic status in men and women aged 26-81 y. DESIGN: We assessed the cross-sectional associations of self-reported phylloquinone (vitamin K(1)) intake with insulin sensitivity and glycemic status in the Framingham Offspring Cohort. Dietary and supplemental phylloquinone intakes were assessed by using a food-frequency questionnaire. Insulin sensitivity was measured by fasting and 2-h post-oral-glucose-tolerance test (OGTT) insulin, the homeostasis model assessment of insulin resistance (HOMA-IR), and the insulin sensitivity index (ISI(0,120)). Glycemic status was assessed by fasting and 2-h post-OGTT glucose and glycated hemoglobin (HbA(1c)). RESULTS: Higher phylloquinone intake was associated with greater insulin sensitivity and glycemic status, as measured by 2-h post-OGTT insulin and glucose and ISI(0,120), after adjustment for age, sex, waist circumference, lifestyle characteristics, and diet quality [2-h post-OGTT insulin: lowest and highest quintile, 81.0 and 72.7 microU/mL, respectively (P for trend = 0.003); 2-h post-OGTT glucose: 106.3 and 101.9 mg/dL, respectively (P for trend = 0.009); ISI(0,120): 26.3 and 27.3 mg L(2)/mmol mU min (P for trend = 0.009)]. Phylloquinone intake was not associated with fasting insulin and glucose concentrations, HOMA-IR, or HbA(1c). CONCLUSION: Our findings support a potential beneficial role for phylloquinone in glucose homeostasis in men and women.     

Surrogate markers of insulin resistance are associated with consumption of sugar-sweetened drinks and fruit juice in middle and older-aged adults

In this study, we examined the association between sugar-sweetened drink, diet soda, and fruit juice consumption and surrogate measures of insulin resistance. Sugar-sweetened drink, diet soda, and fruit juice consumption was estimated using a semiquantitative FFQ in 2500 subjects at the fifth examination (1991-1995) of the Framingham Offspring Study. Surrogate markers of insulin resistance measured in this study included fasting insulin, fasting glucose, homeostatic model assessment of insulin resistance, and the insulin sensitivity index (ISI(0,120)). Sugar-sweetened drink consumption was positively associated with fasting insulin (none vs. > or = 2 servings/d, 188 vs. 206 pmol/L, P-trend <0.001) after adjusting for potential confounders. Sugar-sweetened drink consumption was not associated with fasting glucose or ISI(0,120). Fruit juice consumption was inversely associated with fasting glucose (none vs. > or = 2 servings/d, 5.28 vs. 5.18 mmol/L, P-trend = 0.006), but not with fasting insulin (none vs. > or = 2 servings/d, 200 vs. 188 pmol/L, P-trend = 0.37) or ISI(0,120) (none vs. > or = 2 servings/d, 26.0 vs. 27.0, P-trend = 0.19) in multivariate models. Diet soda consumption was not associated with any surrogate measures of insulin resistance after adjustment for potential confounders (insulin: none vs. > or = 2 servings/d, 195 vs. 193 pmol/L, P-trend = 0.59; glucose: 5.26 vs. 5.24 mmol/L, P-trend = 0.84; and ISI(0,120): 26.2 vs. 26.7, P-trend = 0.37). In these healthy adults, sugar-sweetened drink consumption appears to be unfavorably associated with surrogate measures reflecting hepatic more than peripheral insulin sensitivity. Studies of long-term beverage consumption using more direct measures of insulin sensitivity are clearly warranted.     

西格列汀联合二甲双胍治疗初诊2型糖尿病的疗效观察

目的 探讨西格列汀联合二甲双胍治疗初发、肥胖2型糖尿病的临床疗效.方法 选取2012年1月至2013年12月期间在我院治疗的180例初发、肥胖2型糖尿病患者为研究对象,将其随机分为治疗组和对照组,其中治疗组92例,对照组88例.对照组患者给予格列美脲＋二甲双胍治疗,治疗组给予二甲双胍＋西格列汀治疗.入组前常规进行肝肾功能、血糖血脂、糖化血红蛋白、胰岛细胞分泌功能、胰岛素抵抗等评估,治疗期24周.治疗结束后分析两组患者的在体重、空腹血糖、餐后2小时血糖、糖化血红蛋白、胰岛细胞分泌功能、胰岛素抵抗指数等方面的差异.结果 治疗组患者各项监测指标（空腹及餐后血糖、糖化血红蛋白、胰岛细胞分泌功能、胰岛素抵抗指数）明显好于对照组患者（P＜0.05）,且治疗组的总有效率92.40％ （85/92）和对照组患者72.73％ （64/88）相比占优势,两组患者比较差异具有统计学意义（P＜0.05）.两组患者在体重、低血糖发作方面无明显差异（P＞0.05）.结论 二甲双胍联合西格列汀治疗初发、肥胖2型糖尿病患者安全有效,值得借鉴.     

Risk of type 2 diabetes mellitus in young adults from a biracial community: the Bogalusa Heart Study

BACKGROUND: Since type 2 diabetes has a strong familial component, characteristics of young adult offspring of type 2 diabetics were examined in a community sample to determine early abnormalities in black and white persons at risk. METHODS: The sample consisted of 1,338 fasting young adults (72% white, 28% black) aged 19 to 37 years from a biracial community, including those with positive parental history of type 2 diabetes (one offspring per family, n = 230) or conditions of impaired fasting glucose and type 2 diabetes (n = 22). RESULTS: Positive family history of diabetes or impaired fasting glucose and type 2 diabetes in young adults of both races were significantly associated with adverse profiles of measures of obesity and abdominal fat (body mass index, triceps and subscapular skinfolds, waist circumference, and abdominal height), systolic and diastolic blood pressures, serum total cholesterol, triglycerides, VLDL cholesterol, and HDL cholesterol, and indicators of glucose homeostasis (plasma glucose and insulin and insulin resistance index). The magnitude of the differences in obesity and abdominal fat measures and plasma glucose between individuals with and without parental diabetes was greater among blacks versus whites (P = 0. 047-0.004). Further, black offspring of both diabetics and non-diabetics had unfavorable profiles of obesity and abdominal fat measures, blood pressure, insulin, and insulin resistance index (P = 0.0001). In a multivariate analysis, adiposity measured as body mass index (P = 0.03) and plasma glucose (P = 0.003) emerged as the two independent characteristics that distinguished those with parental diabetes from those without parental disease. Insulin (P = 0.0001) and the insulin resistance index (P = 0.0001) were independently associated with conditions of impaired fasting glucose or type 2 diabetes. CONCLUSIONS: The risk factors of young adults with parental type 2 diabetes or conditions of impaired fasting glucose and type 2 diabetes can be detected early. These observations have implications for early prevention and intervention, especially for blacks.     

Pro12Ala polymorphism of the PPARG2 gene is associated with type 2 diabetes mellitus and peripheral insulin sensitivity in a population with a high intake of oleic acid

Activation of the PPAR gamma 2 gene (PPARG2) improves the action of insulin and its lipid metabolism. We examined the association between Pro12Ala polymorphism of PPARG2, type 2 diabetes mellitus (DM2), and peripheral insulin sensitivity in a population with a high intake of oleic acid. A cross-sectional, population-based study was undertaken in Pizarra, a small town in the province of Malaga in southern Spain. A total of 538 subjects, aged 18-65 y, were selected randomly from the municipal census. All subjects underwent a clinical, anthropometrical, and biochemical evaluation, including an oral glucose tolerance test and Pro12Ala polymorphism of PPARG2. Insulin resistance was measured by homeostasis model assessment. Those subjects with the Ala-12 allele had an odds ratio for impaired fasting glucose of 0.55, for impaired glucose tolerance of 0.59, and for DM2 of 0.30. The intake of monounsaturated fatty acids (MUFA) contributed to the variance of the homeostasis model assessment insulin resistance index (HOMA IR) (P = 0.04), with a 2-way interaction between the Ala-12 allele of PPARG2 and the intake of MUFA (P = 0.005). The results suggest the existence of an interaction between Pro12Ala polymorphism of PPARG2 and dietary MUFA, such that obese people with the Ala-12 allele have higher HOMA IR values, especially if their intake of MUFA is low.     

Dietary glycemic index and load, measures of glucose metabolism, and body fat distribution in older adults

BACKGROUND: Recent evidence suggests that the rate of carbohydrate digestion and absorption may influence the development of type 2 diabetes. OBJECTIVE: The aim of this study was to examine associations of dietary glycemic index and glycemic load with predictors of type 2 diabetes in older adults. DESIGN: This study evaluated cross-sectional relations of dietary glycemic index and glycemic load with measures of glucose metabolism and body fat distribution in participants of the Health, Aging and Body Composition Study, a prospective cohort study of adults aged 70-80 y (n = 2248). RESULTS: In men, dietary glycemic index was positively associated with 2-h glucose (P for trend = 0.04) and fasting insulin (P for trend = 0.004), inversely associated with thigh intramuscular fat (P for trend = 0.02), and not significantly associated with fasting glucose, glycated hemoglobin, or visceral abdominal fat. Dietary glycemic load was inversely associated in men with visceral abdominal fat (P for trend = 0.02) and not significantly associated with fasting glucose, 2-h glucose, glycated hemoglobin, fasting insulin, or thigh intramuscular fat. In women, although dietary glycemic index and load were not significantly related to any measures of glucose metabolism or body fat distribution, the association between dietary glycemic index and 2-h glucose was nearly significant (P for trend = 0.06). CONCLUSION: The findings of this cross-sectional study indicate an association between dietary glycemic index and selected predictors of type 2 diabetes in older adults, particularly in men.     

Correlation between insulin resistance and puberty in children with increased cardiometabolic risk

Epidemiologic data provide evidence that the frequency of obesity and cardiometabolic risk factors shows an increasing tendency in childhood. Insulin resistance plays a central role in the pathogenesis of cardiovascular and metabolic consequences of obesity. Transient decrease in the insulin sensitivity during puberty is a well-known physiological process; however, the feature of this phenomenon is not clear in obese children with increased cardiometabolic risk. AIM: The aim of the present study was to assess the effect of puberty on insulin resistance and metabolic parameters in obese children with and without increased cardiometabolic risk. MATERIALS AND METHODS: Anthropometric data, insulin levels during oral glucose tolerance test and lipid status were analyzed of 161 obese children aged 4-18 years. Σinsulin/Σglucose ratio was obtained during glucose load and HOMA index was used to assess insulin resistance. Children were sorted into prepubertal (T1), pubertal (T2-4) and postpubertal (T5) cohorts according to Tanner staging criteria and metabolic and insulin resistance parameters were evaluated. Increased cardiometabolic risk was defined as the presence of any two risk factors (elevated fasting plasma glucose, blood pressure, triglyceride or decreased HDL-cholesterol) in addition to obesity. Results: Out of 161 obese subjects, 43 (26.7%) had increased cardiometabolic risk. Decreased HDL-cholesterol and/or elevated triglyceride was observed in 101 (56.5%) cases. Impaired glucose tolerance and/or impaired fasting glucose was found in 23 (14.4%) cases. In subjects without increased cardiometabolic risk, the Σinsulin/Σglucose ratio in T1 stage was significantly lower than in T2-4 and T5 stages (p = 0.01). In children with increased cardiometabolic risk, the insulin/glucose ratio was similar in T1, T2-4 and T5 stages, however, it was significantly higher in T1 stage as compared to subjects without increased cardiometabolic risk (p = 0.04). In T2-4 and T5 stages, Σinsulin/Σglucose ratio did not differ between children with and without increased cardiometabolic risk. No difference was found in HOMA index between groups with and without increased cardiometabolic risk in T1 stage, however significantly higher levels were observed in subjects with increased cardiometabolic risk at T2-4 stages (p = 0.01), indicating the presence of fasting hyperinsulinemia in this cohort. Elevated HbA1c (≥6.0%) was found in 13 (16%) out of the 81 children investigated, of whom only two cases had abnormal oral glucose tolerance test. In cases having normal HbA1c, oral glucose tolerance test showed impaired glucose tolerance in 5 cases, impaired fasting glucose in 2 cases, both impaired glucose tolerance and impaired fasting glucose in 2 cases, and type 2 diabetes in 2 cases. Conclusion: Increased insulin resistance can be observed in obese children without increased cardiometabolic risk. In obese children with increased cardiometabolic risk, substantial insulin resistance occurs in prepuberty and it is present at similar level throughout puberty. Fasting insulin levels are elevated in obese subjects with increased cardiometabolic risk as compared to those without increased cardiometabolic risk. To reveal type 2 diabetes cases, HbA1c and oral glucose tolerance test results should be assessed parallel.     

肥胖儿童血清瘦素水平分析

目的:检测肥胖儿童和正常对照儿童血清瘦素水平,探讨瘦素与体重指数、空腹血糖、胰岛素、胰岛素抵抗指数及血脂等的相关性。方法:对100例肥胖儿童及100例正常对照儿童测量身高、体重,计算体重指数(BMI);检测空腹血糖(FPG)、胰岛素(FINS)、总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)、载脂蛋白A(ApoA)、载脂蛋白B(ApoB);胰岛素抵抗采用稳态模式评估法的胰岛素抵抗指数(HOMA-IR)指标;血清瘦素采用酶联免疫吸附试验检测。结果:肥胖儿童组血清瘦素显著高于正常对照组儿童(P<0.05);血清瘦素与BMI、ALT、TG、LDL-C、APB、FINS、HOMA呈正相关r,值分别为(0.647,0.5840,.328,0.198,0.314,0.5230,.484,P值均<0.05);与HDL-C呈负相关(r=-0.151,P<0.05)。结论:瘦素作为一种脂肪因子,在儿童肥胖的发生中起重要作用。     

Magnesium intake is related to improved insulin homeostasis in the framingham offspring cohort

OBJECTIVE: Higher dietary intake of magnesium may protect against development of type 2 diabetes. The aim of this study was to examine the association between dietary magnesium intake and metabolic risk factors for diabetes. METHODS: We examined cross-sectional associations between magnesium intake and fasting glucose and insulin, 2-hour post-challenge plasma glucose and insulin, and insulin resistance assessed by the homeostasis model (HOMA-IR) in 1223 men and 1485 women without diabetes from the Framingham Offspring cohort. Magnesium intake was assessed by a food frequency questionnaire and magnesium intake was categorized into quintile categories. Geometric mean insulin, glucose, 2-hour post challenge plasma glucose and insulin concentrations and HOMA-IR were estimated across quintile categories of magnesium intake using Generalized Linear Models. RESULTS: After adjustment for potential confounding factors, magnesium intake was inversely associated with fasting insulin (mean: 29.9 vs 26.7 microU/mL in the lowest vs highest quintiles of magnesium intake; P trend <0.001), post-glucose challenge plasma insulin (86.4 vs 72 microU/mL; P trend <0.001), and HOMA-IR (7.0 vs 6.2; P trend <0.001). No significant association was found between magnesium intake and fasting glucose or 2-hour post challenge glucose. CONCLUSIONS: Improved insulin sensitivity may be one mechanism by which higher dietary magnesium intake may reduce the risk of developing type 2 DM.     

Insulin-mediated effects of alcohol intake on serum lipid levels in a general population: the Hisayama Study

To determine whether the beneficial effects of alcohol on lipid concentrations are mediated by insulin levels, we performed a cross-sectional analysis in 2103 nondiabetic men and women aged 40 to 79 years from a general Japanese population in Hisayama. The multivariate-adjusted sum of fasting and 2-hour postloading insulin levels and the insulin resistance index significantly decreased with elevating alcohol intake levels in men (P < 0.01 for the trend) but not in women. No dose-response relations between alcohol intake and glucose levels were observed. In both sexes, high-density lipoprotein cholesterol (HDLC) significantly increased with elevated alcohol intake (P < 0.01), whereas total cholesterol and low-density lipoprotein cholesterol (LDLC) were inversely correlated with alcohol intake (P < 0.01). In contrast, triglycerides (TGs) levels in men showed a J-shaped relation to alcohol dose, with moderate drinkers (10-29 g/d) having the lowest levels. Estimates using regression models indicated that for men, 10% of the alcohol-induced increase in HDLC and 2% of the alcohol-induced decrease in LDLC were insulin mediated. It was also estimated for male subjects that 36% of the reduction in TGs due to low to moderate alcohol intake was mediated by low levels of insulin and that this insulin-mediated pathway reduced the positive alcohol-TG relation by 13% in cases of moderate to heavy drinking. Our data suggest that regular alcohol consumption dose-dependently increased insulin sensitivity among male nondiabetics, but the insulin-mediated beneficial effects of alcohol on lipid concentrations were relatively small.     

Obese Japanese adults with type 2 diabetes have higher basal metabolic rates than non-diabetic adults

Several cross-sectional studies in Pima Indians and Caucasians have indicated that obese individuals with type 2 diabetes have a higher basal metabolic rate (BMR) than healthy, obese individuals. However, no study has investigated this comparison in Japanese subjects, who are known to be susceptible to type 2 diabetes due to genetic characteristics. Thirty obese Japanese adults with pre-type 2 diabetes (n=7) or type 2 diabetes (n=13) or without diabetes (n=10) participated in this study. BMR was measured using indirect calorimetry. The relationships between residual BMR (calculated as measured BMR minus BMR adjusted for fat-free mass, fat mass, age, and sex) and biomarkers including fasting glucose, glycosylated hemoglobin (HbA(1c)), fasting insulin, homeostasis model assessment of insulin resistance (HOMA-R), triglycerides, and free fatty acids were examined using Pearson's correlation. BMR in diabetic subjects adjusted for fat-free mass, fat mass, age, and sex was 7.1% higher than in non-diabetic subjects. BMR in diabetic subjects was also significantly (p<0.05) higher than in non-diabetic subjects. There was a significant correlation between residual BMR and fasting glucose (r=0.391, p=0.032). These results indicate that in the Japanese population, obese subjects with type 2 diabetes have higher BMR compared with obese non-diabetic subjects. The fasting glucose level may contribute to these differences.     

Dietary intakes and plasma concentrations of carotenoids and tocopherols in relation to glucose metabolism in subjects at high risk of type 2 diabetes: the Botnia Dietary Study

BACKGROUND: The role of antioxidants in the pathogenesis of type 2 diabetes is uncertain. OBJECTIVE: We evaluated cross-sectional relations of dietary intakes and plasma concentrations of antioxidants with glucose metabolism in a high-risk population. DESIGN: The subjects were 81 male and 101 female first- and second-degree, nondiabetic relatives of patients with type 2 diabetes. Antioxidant intake data were based on 3-d food records. Subjects taking supplements containing beta-carotene or alpha-tocopherol were excluded. Plasma antioxidant concentrations were measured by HPLC. By using multiple linear regression analysis and adjusting for demographic, anthropometric, and lifestyle covariates, we studied whether dietary and plasma alpha- and beta-carotene, lycopene, and alpha- and gamma-tocopherol were related to fasting and 2-h concentrations of glucose and nonesterified fatty acids during an oral-glucose-tolerance test, to the homeostasis model assessment index of insulin resistance, and to measures of beta cell function (incremental 30-min serum insulin concentration during an oral-glucose-tolerance test and first-phase insulin secretion during an intravenous-glucose-tolerance test). RESULTS: In men, dietary carotenoids were inversely associated with fasting plasma glucose concentrations (P < 0.05), plasma beta-carotene concentrations were inversely associated with insulin resistance (P = 0.003), and dietary lycopene was directly related to baseline serum concentrations of nonesterified fatty acids (P = 0.034). In women, dietary alpha-tocopherol and plasma beta-carotene concentrations were inversely and directly associated, respectively, with fasting plasma glucose concentrations (P < 0.05). In both sexes, cholesterol-adjusted alpha-tocopherol concentrations were directly associated with 2-h plasma glucose concentrations (P < 0.05). CONCLUSION: The data suggest an advantageous association of carotenoids, which are markers of fruit and vegetable intake, with glucose metabolism in men at high risk of type 2 diabetes.     

Alcohol consumption and higher incidence of impaired fasting glucose or type 2 diabetes in obese Korean men

It is inconclusive whether moderate alcohol consumption reduces the diabetes risk. We observed the development of impaired fasting glucose or type 2 diabetes according to the amount of alcohol intake and body mass index. The annual health evaluation data of 2,500 male workers from 2002 to 2006 were reviewed retrospectively deleting personal identification code. The information contained sex, age, medical history, smoking status, alcohol consumption, participating regular exercise, anthropometric, and biochemistry measurement. Impaired fasting glucose or diabetes was determined when fasting plasma glucose was ≥100 mg/dL. Thousand seven hundred seven subjects were eligible after excluding medical history of diabetes or fasting glucose ≥100 mg/dL at baseline. The relative risks of its development in group of taking 1-14, 15-29, and ≥30.0 g ethanol were 0.842 (95% confidence interval [CI], 0.603-1.176), 1.068 (95% CI, 0.736-1.551), and 1.019 (95% CI, 0.662-1.568) within normal weight group, 1.164 (95% CI, 0.795-1.705), 1.421 (95% CI, 0.947-2.133), and 1.604 (95% CI, 1.031-2.495) within overweight group, and 1.498 (95% CI, 1.042-2.153), 1.634 (95% CI, 1.091-2.447), and 1.563 (95% CI, 1.019-2.396) within obese group each after adjusting age, family history of diabetes, smoking, exercise, serum fasting glucose, aspartate aminotransferase, and γ-glutamyltransferase with nondrinkers as a reference group. Not only high alcohol consumption but also moderate drinking was related with higher incidence of impaired fasting glucose or diabetes in obese Korean men.     

Prevalence of non-traditional cardiovascular disease risk factors among persons with impaired fasting glucose, impaired glucose tolerance, diabetes, and the metabolic syndrome: analysis of the Third National Health and Nutrition Examination Survey (NHANES III)

PURPOSE: To calculate the prevalence of non-traditional cardiovascular disease (CVD) risk factors across diabetes status and for persons with and without the metabolic syndrome. METHODS: Data were analyzed from the Third National Health and Nutrition Examination Survey for normal plasma glucose [<100 mg/dl, n=4589]; impaired fasting glucose [IFG, 100-125 mg/dl, n=2008], diabetes [fasting glucose #10878; 126 mg/dl or diabetes medication, n=750]; and participants with and without the metabolic syndrome, n=1938 and n=5409, respectively. RESULTS: After adjustment for age, race, sex, body mass index, physical inactivity, cigarette smoking and alcohol consumption, a higher odds (p-trend < 0.01) of the metabolic syndrome, an elevated HOMA-insulin resistance index, chronic kidney disease, elevated C-reactive protein, high fibrinogen, and high white blood cell count was observed across diabetes status. After similar adjustment, the metabolic syndrome was associated with (odds ratio; 95% confidence interval) low apolipoprotein A1 (2.27: 1.30,3.96), high apolipoprotein-B (2.97: 2.03,4.34), a higher HOMA insulin resistance index (5.25: 4.16, 6.63), chronic kidney disease (2.27: 1.42, 3.63), and elevated markers of inflammation [high white blood cell count (1.55: 1.14, 2.10), and elevated C-reactive protein (1.46: 1.06, 2.00)]. Among participants with IFG, the presence of impaired glucose tolerance (IGT) was associated with a higher prevalence of the HOMA insulin reistance index, 32.3%, high fibrinogen, 18.5%, and elevated C-reactive protein, 13.2%, compared to persons with IFG alone, 19.7%, 13.3% and 5.7%, respectively (each p <== 0.05). CONCLUSIONS: In this representative of the US population, an increased prevalence of non-traditional CVD risk factors was present among persons with diabetes, IGT and IFG compared to IFG alone, and the metabolic syndrome.     

Characterization of the impaired glucose homeostasis produced in C57BL/6 mice by chronic exposure to arsenic and high-fat diet

Background: Type 2 diabetes is characterized by glucose intolerance and insulin resistance. Obesity is the leading cause of type 2 diabetes. Growing evidence suggests that chronic exposure to inorganic arsenic (iAs) also produces symptoms consistent with diabetes. Thus, iAs exposure may further increase the risk of diabetes in obese individuals.Objectives: Our goal was to characterize diabetogenic effects of iAs exposure and high-fat diet (HFD) in weaned C57BL/6 mice.Methods: Mice were fed HFD or low-fat diet (LFD) while exposed to iAs in drinking water (25 or 50 ppm As) for 20 weeks; control HFD and LFD mice drank deionized water. Body mass and adiposity were monitored throughout the study. We measured glucose and insulin levels in fasting blood and in blood collected during oral glucose tolerance tests (OGTT) to evaluate the diabetogenic effects of the treatment.Results: Control mice fed HFD accumulated more fat, had higher fasting blood glucose, and were more insulin resistant than were control LFD mice. However, these diabetes indicators decreased with iAs intake in a dose-dependent manner. OGTT showed impaired glucose tolerance for both control and iAs-treated HFD mice compared with respective LFD mice. Notably, glucose intolerance was more pronounced in HFD mice treated with iAs despite a significant decrease in adiposity, fasting blood glucose, and insulin resistance.Conclusions: Our data suggest that iAs exposure acts synergistically with HFD-induced obesity in producing glucose intolerance. However, mechanisms of the diabetogenic effects of iAs exposure may differ from the mechanisms associated with the obesity-induced type 2 diabetes.     

Alcohol reduces insulin-hypertension relationship in a general population: the Hisayama study

Insulin resistance may be a factor in the etiology of hypertension, and habitual alcohol intake may modify this relationship. We prospectively examined this hypothesis in 1,133 nonhypertensive, nondiabetic Japanese subjects, aged 40-79 years. Alcohol drinkers were more frequent among men than women at baseline (57.7 vs. 8.2%). The age-adjusted incidence of hypertension significantly increased with the elevating baseline insulin levels in women (P =.003 for trend), but not in men. The age- and sex-adjusted insulin levels and insulin resistance index decreased with elevating alcohol intake, while fasting glucose levels remained unchanged, suggesting that alcohol improves insulin sensitivity. Among nondrinkers, the age-adjusted incidence of hypertension significantly increased with elevating insulin tertiles in both sexes (P =.048 and.002 for trend in men and women, respectively), but not among drinkers. Our findings suggest a close association between insulin resistance and the incidence of hypertension in Japanese. However, alcohol modified and reduced this relationship.