Short-term aerobic exercise training increases postprandial pancreatic polypeptide but not peptide YY concentrations in obese individuals.

OBJECTIVE: Short-term exercise training improves glycemic control, but the effect of short-term training on postprandial satiety peptide responses or perceived satiety remains unknown. We tested the hypothesis that short-term aerobic exercise training (15 days) would alter postprandial pancreatic and gut peptide (pancreatic polypeptide (PP) and peptide YY (PYY)) responses and perceived appetite and satiety in obese individuals. SUBJECTS: Thirteen healthy obese men and women (age: 42±2 years; body mass index: 30-45 kg m(-2)). MEASUREMENTS: Subjects were studied before and after 15 days of training (walking 1 h at 70-75% VO(2peak)). On the study day, subjects consumed 1500 kcal as six meals (250 kcal: 9 g protein, 40 g carbohydrate, 6 g fat), while blood samples and satiety measurements were taken at baseline and every 20 min for 12 h. Blood was analyzed for PP, PYY, glucose and insulin levels. Appetite and satiety was assessed with a visual analog scale throughout the day. RESULTS: Incremental area under the curve (iAUC) for PP increased significantly with training (pre: 2788±753; post: 3845±830 pg ml(-1)·per min for 12 h; P<0.001), but there was no difference in the PP response to each meal. The initial PP response to the first meal increased (ΔPP(min 20-0): pre 86±25; post 140±36 pg ml(-1); P<0.05) with training. PYY iAUC showed no significant changes with training but showed a significant main effect of time across meals, with the largest response being to the first meal (P<0.005). There were no changes in satiety, glucose or insulin levels with training. CONCLUSION: Short-term exercise training increases postprandial PP concentrations in obese individuals; however, PYY levels and glycemic control remain unaffected. Both PP and PYY show meal-induced increases at all meals, but PYY has a greater response at the first meal with reduced responses at subsequent meals.

Weight-loss-associated changes in bone mineral density and bone turnover after partial weight regain with or without aerobic exercise in obese women.

BACKGROUND/OBJECTIVES: Moderate, long-term weight loss results in the loss of bone mass in overweight or obese premenopausal women. However, whether these changes persist during weight maintenance or regain remains to be determined. SUBJECTS/METHODS: Overweight or obese (body mass index: 25.8-42.5 kg/m(2)) women (n=40) with at least two risk factors for the metabolic syndrome participated in this 12-month study that examined the effects of prescribed weight loss and regain, with or without exercise, on bone turnover and on bone mineral density (BMD) in a subset of participants (n=24). During the first 6 month, participants lost ≈ 10% of their initial body weight via energy restriction and supervised aerobic exercise. Following weight loss, participants were randomly assigned to either an exercise or a no exercise treatment for the regain (+50% of weight lost) phase. A one-way (time) repeated measures one-factor analysis of variance (RMANOVA) tested the effects of weight loss on BMD and bone turnover, and a two-way RMANOVA (time, exercise) was used to examine the effects of exercise during weight regain. RESULTS: Hip (P=0.007) and lumbar spine (P=0.05) BMD decreased with weight loss, and remained reduced after weight regain with or without exercise. Likewise, the weight-loss-associated increases in osteocalcin (P<0.001) and C-terminal peptide of type I collagen (P<0.001) persisted following weight regain, independent of exercise. CONCLUSIONS: The results of the present study, which is the first to examine changes in bone mass and turnover during carefully controlled weight regain, suggest that weight-loss-induced perturbations in bone mass and turnover persist after partial weight regain, regardless of whether regular weight-bearing aerobic exercise was continued.

Cardiovascular risk modification in participants with coronary disease screened by the Kidney Early Evaluation Program.

BACKGROUND: Coronary artery disease (CAD) identifies the need for intensive treatment of risk factors among individuals with chronic kidney disease (CKD), a high-risk, complex cardiovascular risk state. METHODS: An estimated glomerular filtration rate<60 mL/min/1.73 m2 or a urine albumin:creatinine ratio (ACR)≥30 mg/g (3.4 mg/mmol) defined CKD. RESULTS: Of 70,454 volunteers screened the mean age was 53.5±15.7 years and 68.3% were female. A total of 5410 (7.7%) had a self-reported history of CAD; 1295 (1.8%) had a history of prior percutaneous coronary intervention (PCI); and 1124 (1.6%) had a prior history of coronary artery bypass surgery (CABG). Multivariate analysis for the outcome of suboptimal CAD risk management (composite of systolic blood pressure≥130 mmHg, glucose≥125 mg/dL (6.9 mmol/L) for diabetics, total cholesterol≥200 mg/dL (5.2 mmol/L), or current smoking; n=38,746/53,403, 72.5%) revealed older age (per year) (odds ratio (OR)=1.04, 95% confidence interval (CI) 1.03-1.04, P<0.0001), male gender (OR=1.40, 95% CI 1.34-1.47, P<0.0001), ACR≥30 mg/g (3.4 mg/mmol) (OR=1.66, 95% CI 1.55-1.79, P<0.0001), body mass index (per kg/m2) (OR=1.06, 95% CI 1.06-1.06, P<0.0001), CAD without a history of revascularization (OR=1.14, 95% CI 1.02-1.28, P=0.02) and care received by a nephrologist (OR=1.49, 95% CI 1.22-1.83, P<0.0001) were associated with worse risk factor control. Prior coronary revascularization and being under the care of a cardiologist were not associated with either improved or suboptimal risk factor control. CONCLUSIONS: Chronic kidney disease is associated with overall poor rates of CAD risk factor control.

Slower decline of renal function after initiation of rosiglitazone in diabetics -- a pilot study.

BACKGROUND: To translate laboratory data to the bedside, we hypothesized that initiation of a thiazolidinedione would reduce the rate of progression of renal insufficiency in diabetic subjects. METHODS: We included subjects initiated on rosiglitazone for control of diabetes who had at least two consecutive serum creatinine values >= 1.5 mg/dl that were at least 4 weeks apart. We used slope estimates of reciprocal of creatinine vs. time (days) from linear models to derive the rate of decline of renal function before (Phase 1) and after (Phase 2) rosiglitazone initiation. The adjusted rate of decline of renal function was derived using repeated measure models weighted by inverse variances adjusting for hemoglobin A1C and mean blood pressure. RESULTS: There were 114 subjects (113 men, 1 woman; mean age 66.8 +/- 9.4 years). The mean duration of Phase 1 was 586.2 +/- 275.6 days and Phase 2 was 613.2 +/- 281.7 days (p = 0.47). The mean unadjusted Phase 1 slope of reciprocal creatinine vs. time was -0.00015 +/- 0.00021 and the Phase 2 slope was -0.00009 +/- 0.00021. The mean slope difference (Phase 2 - Phase 1) was 0.00005 +/- 0.00031 (p < 0.0001 for Wilcoxon signed rank test and p = 0.0023 for t-test). The adjusted difference in the mean slope was 0.00007 +/- 0.00042 (p = 0.0135). CONCLUSION: There was a slower rate of decline of renal function after initiation of rosiglitazone in diabetic subjects with renal insufficiency. These findings warrant confirmation by a prospective randomized trial.

Low birth weight is associated with chronic kidney disease only in men.

The association of low birth weight and chronic kidney disease was examined in a screened volunteer population by the National Kidney Foundation's Kidney Early Evaluation Program. This is a free, community-based health program enrolling individuals aged 18 years or older with diabetes, hypertension, or a family history of kidney disease, diabetes, or hypertension. Self-reported birth weight was categorized and chronic kidney disease defined as an estimated glomerular filtration rate less than 60 ml per min per 1.73 m(2) or a urine albumin/creatinine ratio >or=30 mg/g. Among 12 364 participants, 15% reported a birth weight less than 2500 g. In men, significant corresponding odds ratios were found after adjustment for demographic characteristics and health conditions to this low birth weight and chronic kidney disease, but there was no association among women. There was no significant interaction between birth weight and race for either gender. Efforts to clinically understand the etiology of this association and potential means of prevention are essential to improving public health.