Dietary sodium intake deleteriously affects blood pressure in a normotensive population.

Western dietary pattern, and particularly high dietary sodium intake (DSI), is recognized for its detrimental impact on blood pressure (BP). This paper examined the association of DSI with BP in Nunavik Inuit (Québec), a population known to have an optimal BP on average. In a population-based study, we recruited 421 normotensive participants aged 18-74 years from 14 coastal villages, situated north of the 55th parallel. BP, biochemistry and anthropometry were obtained. DSI was assessed by a 24-h dietary recall. Mean (s.e.) DSI was higher in men than in women (2358 (101) vs. 1702 (100) mg/d, P<0.0001). Similar gender difference was found in systolic BP (118 (0.7) vs. 111 (0.6) mm Hg; P<0.0001). After adjustment for confounders, we found a positive association between BP and DSI (all P<0.05). In a normotensive population, BP shows a linear relationship with DSI. Our results emphasize the potent deleterious impact of DSI on BP.

The beta-1 adrenergic antagonist, atenolol, decreases acylation stimulating protein, exercise capacity and plasma free fatty acids in men with type 2 diabetes.

BACKGROUND AND AIMS: Atenolol is a beta-1 adrenergic antagonist commonly prescribed for the treatment of systemic hypertension or coronary artery disease yet its use in individuals with type 2 diabetes mellitus (T2DM) is controversial due to potentially negative side effects on insulin resistance. Non-esterified fatty acid (NEFA) metabolism is altered in T2DM especially under conditions of metabolic stress such as exercise or the postprandial state. We evaluated atenolol effects on circulating NEFA and related hormones in men with T2DM during acute cardiorespiratory exercise in both the fasting and postprandial state, including the adipokine acylation stimulating protein (ASP) which stimulates adipose tissue NEFA uptake. METHODS AND RESULTS: Ten men with T2DM underwent four 1-h exercise sessions at 60% of their maximal oxygen uptake (VO(2max)) under the following conditions: 1) fasting (F), and 2) 2 h postprandial (PP) without medication; and 3) fasting (F-Atenolol), and 4) 2 h postprandial (PP-Atenolol) after a one-week treatment with atenolol. Results were tested for the effects of atenolol via two-way ANOVA for the F vs F-Atenolol and PP vs PP-Atenolol states separately. Atenolol treatment decreased fasting and postprandial glycerol (p < 0.0001) and NEFA (p < 0.0001), postprandial epinephrine (p = 0.048), postprandial cortisol (p = 0.02), postprandial ASP (p = 0.04) and postprandial dopamine (p < 0.004). CONCLUSION: Atenolol alters fatty acid metabolism and associated metabolic hormones including ASP during exercise in men with T2DM and its effects are more apparent during conditions of stress such as the postprandial state, acute exercise and obesity.

Successful reversal of recurrent spinal cord ischemia following endovascular repair of a descending thoracic aortic aneurysm.

Despite recent advances in technique, spinal cord ischemia remains one of the most dreaded complications of thoracic aortic surgery. Recently, it has been suggested that thoracic endovascular aortic repair may decrease the risk of paraplegia. We present a case of delayed paraplegia following thoracic endovascular aortic repair that was successfully reversed on 3 separate occasions in the same patient. This highlights the importance of vigilant clinical assessments, efficient multidisciplinary teamwork, and maintenance of the determinants of spinal cord perfusion following endovascular thoracic aortic intervention.

Is marine mammal fat or fish intake most strongly associated with omega-3 blood levels among the Nunavik Inuit?

Here we determined the relationship between red blood cell (RBC) omega-3 (n-3) long-chain polyunsaturated fatty acids (LC-PUFAs) and usual dietary marine food product intake among 630 Nunavik Inuit adults. Marine food product intake was determined by a food frequency questionnaire (FFQ) and fatty acids were quantified in RBC membranes. Multiple linear regression was undertaken to determine the relationship between marine food product intake and RBC n-3 LC-PUFAs (dependent variable). Mean RBC n-3 LC-PUFA level was 9.16 ± 0.11% [SEM]. The highest correlations noted with RBC n-3 LC-PUFAs were for marine mammal fat (r(s)=0.41, P<0.0001) and fish (r(s)=0.35, P<0.0001). Age, total marine mammal fat and fish intakes were the variables that contributed the most to predicted RBC n-3 LC-PUFAs and explained 34%, 15% and 5%, respectively, of its variances. Our study indicates that marine mammal fat intake is more important than fish in accounting for RBC n-3 LC-PUFA levels among the Nunavik Inuit.

Impact of high-fat /low-carbohydrate, high-, low-glycaemic index or low-caloric meals on glucose regulation during aerobic exercise in Type 2 diabetes.

AIMS: A decrement in blood glucose (BG) may be observed in patients with Type 2 diabetes (T2DM) when exercise is performed after a meal, in contrast to fasting. We determined the impact of different pre-exercise meal macronutrient compositions with modulation of the glycaemic index (GI) on glucose regulation during exercise in patients with T2DM. METHODS: Using a randomized, single-blind crossover design, 10 sedentary men performed five exercise sessions, once after an overnight fast, and also after each of four test meals, consisting of a high-fat/low-carbohydrate meal, a high-GI meal, a low-GI meal, and a low-calorie meal. RESULTS: Pre-exercise BG and insulin levels were comparable for all four meals. Exercise decreased BG and insulin levels during all meal conditions (all P < 0.001) compared with the fasting state in which BG levels did not change. The magnitude of BG and insulin decrements was similar after consuming the low-calorie, the high-GI and the high-fat/low-carbohydrate meals, whereas the low-GI meal induced the lowest BG fall. Adrenaline response was higher after consumption of the high-, the low-GI and the low-caloric meals compared with the high-fat/low-carbohydrate meal and with the fasting state (P < 0.05). CONCLUSIONS: This study underlines the beneficial effect of low-GI foods and the differential impact of pre-exercise meal macronutrient composition on BG decrease. This may protect against exercise-induced hypoglycaemia, and reiterates the safety of exercising while fasting in T2DM patients.

Sibutramine versus continuous positive airway pressure in obese obstructive sleep apnoea patients.

The aim of the present study was to compare the efficacy of 1 yr of sibutramine-induced weight loss versus continuous positive airway pressure (CPAP) treatment on sleep-disordered breathing, cardiac autonomic function and systemic blood pressure in obese patients with obstructive sleep apnoea. Subjects with a body mass index of > or =30 kg.m(-2) without previous treatment for obstructive sleep apnoea underwent either sibutramine (n = 22) or CPAP (n = 18) treatment for 1 yr. Sibutramine induced a 5.4+/-1.4 kg decrease in body weight compared to the CPAP group, in which no changes in anthropometric variables were observed. The CPAP treatment improved all sleep and respiratory variables, whereas sibutramine-induced weight loss improved only nocturnal arterial oxygen saturation profile. Only CPAP treatment improved night-time systolic and diastolic blood pressure and 24-h and daytime ambulatory diastolic blood pressure. Sibutramine-induced weight loss had no impact on indices of heart rate variability, whereas CPAP treatment increased daytime time domain indices. CPAP treatment for 1 yr had beneficial impacts on nocturnal breathing disturbances, and improved nocturnal oxygenation, night-time systolic and diastolic blood pressure, and daytime cardiac parasympathetic modulation. Sibutramine did not improve sleep-disordered breathing, systemic blood pressure or heart rate variability. There were no adverse effects, such as increment in blood pressure or arrhythmias, associated with this treatment regimen.

Impact of fasting and postprandial state on plasma carnitine concentrations during aerobic exercise in type 2 diabetes.

The effects of metabolic states of fasting and post-absorption on plasma concentrations of free carnitine (FC), acylcarnitine (AC) and total carnitine (TC) were compared during submaximal exercise in subjects with type 2 diabetes mellitus. Ten sedentary men (54+/-5 years) treated with oral hypoglycaemic agents were tested on two separate occasions: following an overnight fast and 2 h after a 395-kcal standardised breakfast. Exercise was performed at 60% of [Formula: see text]O(2peak) on a cycle ergometer for 60 min. Blood samples were drawn at rest for baseline values and following 60 min of exercise and 30 min of recovery. Our results show that: (1) baseline levels of TC, FC and AC were similar in fasted and postprandial groups, (2) TC and AC levels were increased during exercise in the fasted group only, (3) FC levels were decreased during exercise in both fasted and postprandial state and (4) the AC/FC ratio increased during exercise in the fasted group. Our results indicate that the metabolic state of the diabetic patient is associated with a different plasma carnitine status. These patterns may reflect differences in energy metabolism associated with fasting and postprandial hyperglycaemia.

hFE65L influences amyloid precursor protein maturation and secretion.

The amyloid precursor protein (APP) is processed in the secretory and endocytic pathways, where both the neuroprotective alpha-secretase-derived secreted APP (APPs alpha) and the Alzheimer's disease-associated beta-amyloid peptide are generated. All three members of the FE65 protein family bind the cytoplasmic domain of APP, which contains two sorting signals, YTS and YENPTY. We show here that binding of APP to the C-terminal phosphotyrosine interaction domain of hFE65L requires an intact YENPTY clathrin-coated pit internalization sequence. To study the effects of the hFE65L/APP interaction on APP trafficking and processing, we performed pulse/chase experiments and examined APP maturation and secretion in an H4 neuroglioma cell line inducible for expression of the hFE65L protein. Pulse/chase analysis of endogenous APP in these cells showed that the ratio of mature to total cellular APP increased after the induction of hFE65L. We also observed a three-fold increase in the amount of APPs alpha recovered from conditioned media of cells overexpressing hFE65L compared with uninduced controls. The effect of hFE65L on the levels of APPs alpha secreted is due neither to a simple increase in the steady-state levels of APP nor to activation of the protein kinase C-regulated APP secretion pathway. We conclude that the effect of hFE65L on APP processing is due to altered trafficking of APP as it transits through the secretory pathway.