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Objective: Using a mouse model for human-like lipoprotein metabolism, we observed previously that reduction of the hepatic triglyceride (TG) content resulted in a decrease in plasma cholesteryl ester transfer protein (CETP) and an increase in HDL levels. The aim of the current study was to investigate the effects of prolonged caloric restriction in obese patients with type 2 diabetes mellitus, resulting in a major reduction in hepatic TG content, on plasma CETP and HDL levels.Research Design and Methods: We studied 27 obese (BMI: 37.2 ± 0.9 kg/m(2)) insulin-dependent patients with type 2 diabetes mellitus (14 men and 13 women, aged 55 ± 2 years) who received a 16-week very low calorie diet (VLCD). At baseline and after a 16-week VLCD, plasma lipids, lipoproteins, and CETP were measured. Furthermore, functionality of HDL with respect to inducing cholesterol efflux from human monocyte cells (THP-1) was determined.Results: A 16-week VLCD markedly decreased plasma CETP concentration (-18%; P < 0.01) and increased plasma apolipoprotein (apo)AI levels (+16%; P < 0.05), without significantly affecting plasma HDL-cholesterol and HDL-phospholipids. Although a VLCD results in HDL that is less lipidated, the functionality of HDL with respect to inducing cholesterol efflux in vitro was unchanged.Conclusions: The marked decrease in hepatic TG content induced by a 16-week VLCD is accompanied by a decrease in plasma CETP concentration and an increase in apoAI levels, without improving the cholesterol efflux properties of HDL in vitro. [ABSTRACT FROM AUTHOR]

Objective: Physical activity is associated with a reduced risk of developing diabetes and with reduced mortality among diabetic patients. However, the effects of physical activity on the number of years lived with and without diabetes are unclear. Our aim is to calculate the differences in life expectancy with and without type 2 diabetes associated with different levels of physical activity.Research Design and Methods: Using data from the Framingham Heart Study, we constructed multistate life tables starting at age 50 years for men and women. Transition rates by level of physical activity were derived for three transitions: nondiabetic to death, nondiabetic to diabetes, and diabetes to death. We used hazard ratios associated with different physical activity levels after adjustment for age, sex, and potential confounders.Results: For men and women with moderate physical activity, life expectancy without diabetes at age 50 years was 2.3 (95% CI 1.2-3.4) years longer than for subjects in the low physical activity group. For men and women with high physical activity, these differences were 4.2 (2.9-5.5) and 4.0 (2.8-5.1) years, respectively. Life expectancy with diabetes was 0.5 (-1.0 to 0.0) and 0.6 (-1.1 to -0.1) years less for moderately active men and women compared with their sedentary counterparts. For high activity, these differences were 0.1 (-0.7 to 0.5) and 0.2 (-0.8 to 0.3) years, respectively.Conclusions: Moderately and highly active people have a longer total life expectancy and live more years free of diabetes than their sedentary counterparts but do not spend more years with diabetes. [ABSTRACT FROM AUTHOR]

South Asians (SAs) develop type 2 diabetes at a younger age and lower BMI compared with Caucasians (Cs). The underlying cause is still poorly understood but might result from an innate inability to adapt to the Westernized diet. This study aimed to compare the metabolic adaptation to a high-fat, high-calorie (HFHC) diet between both ethnicities. Twelve healthy, young lean male SAs and 12 matched Cs underwent a two-step hyperinsulinemic-euglycemic clamp with skeletal muscle biopsies and indirect calorimetry before and after a 5-day HFHC diet. Hepatic triglyceride content (HTG) and abdominal fat distribution were assessed using magnetic resonance imaging and spectroscopy. At baseline, SAs had higher insulin clamp levels than Cs, indicating reduced insulin clearance rate. Despite the higher insulin levels, endogenous glucose production was comparable between groups, suggesting lower hepatic insulin sensitivity in SAs. Furthermore, a 5-day HFHC diet decreased the insulin-stimulated (nonoxidative) glucose disposal rate only in SA. In skeletal muscle, no significant differences were found between groups in insulin/mammalian target of rapamycin signaling, metabolic gene expression, and mitochondrial respiratory chain content. Furthermore, no differences in (mobilization of) HTG and abdominal fat were detected. We conclude that HFHC feeding rapidly induces insulin resistance only in SAs. Thus, distinct adaptation to Western food may partly explain their propensity to develop type 2 diabetes.

Objective: Thiazolidinediones reduce hepatic steatosis and increase HDL cholesterol levels. In mice with human-like lipoprotein metabolism (APOE*3-Leiden.CETP transgenic mice), a decrease in hepatic triglyceride content is associated with a decrease in plasma cholesteryl ester transfer protein (CETP) mass and an increase in HDL levels. Therefore, the aim of the present study was to assess the effects of pioglitazone on CETP mass in patients with type 2 diabetes., Research Design and Methods: We included 78 men with type 2 diabetes (aged 56.5 +/- 0.6 years; HbA1c 7.1 +/- 0.1%) who were randomly assigned to treatment with pioglitazone (30 mg/day) or metformin (2000 mg/day) and matching placebo, in addition to glimepiride. At baseline and after 24 weeks of treatment plasma HDL cholesterol levels and CETP mass were measured, and hepatic triglyceride content was assessed by proton magnetic resonance spectroscopy. RESULTS Pioglitazone decreased hepatic triglyceride content (5.9 [interquartile range 2.6-17.4] versus 4.1 [1.9-12.3]%, P < 0.05), decreased plasma CETP mass (2.33 +/- 0.10 vs. 2.06 +/- 0.10 microg/ml, P < 0.05), and increased plasma HDL cholesterol level (1.22 +/- 0.05 vs. 1.34 +/- 0.05 mmol/l, P < 0.05). Metformin did not significantly change any of these parameters., Conclusions: A decrease in hepatic triglyceride content by pioglitazone is accompanied by a decrease in plasma CETP mass and associated with an increase in HDL cholesterol levels. These results in patients with type 2 diabetes fully confirm recent findings in mice.

Objective: To evaluate the effects of hyperglycemia due to partial insulin deprivation on myocardial triglyceride (TG) content and myocardial function in patients with type 1 diabetes., Research Design and Methods: Myocardial and hepatic TG content and left ventricular (LV) function were measured by magnetic resonance (MR) spectroscopy and MR imaging during optimal glucoregulation and after 24 h of partial insulin deprivation (n = 10)., Results: Mean insulin infusion rate was 45 +/- 5 units at baseline, whereas it was 27 +/- 5 units during hyperglycemia (per 24 h, P < 0.001). Plasma glucose levels increased from 8.4 +/- 0.6 to 15.9 +/- 0.8 mmol/l (P < 0.001), and plasma levels of nonesterified fatty acids from 0.31 +/- 0.05 to 0.46 +/- 0.07 mmol/l (P = 0.015). Hyperglycemia had no effects on myocardial or hepatic TG content and LV function., Conclusions: Short-term hyperglycemic dysregulation does not modulate myocardial or hepatic TG content or myocardial function, despite considerable metabolic adaptations.