The effects of dietary weight loss with or without exercise training on liver enzymes in obese metabolic syndrome subjects.

AIM: Insulin resistance and visceral adiposity are predisposing factors for fatty liver disease. The main objectives of this study were (i) to compare the effects of caloric restriction (CR) alone or together with moderate-intensity aerobic exercise training (CR+EX) on liver enzymes, a surrogate marker of liver injury, in obese metabolic syndrome (MetS) subjects and (ii) to identify anthropometric, metabolic, cardiovascular and dietary predictors of changes in liver enzymes. METHODS: Sedentary men and women (n = 63), aged 55 ± 6 (s.d.) years with body mass index 32.7 ± 4.1 kg/m(2) and confirmed MetS, were randomized to 12-week CR, CR+EX or no treatment (Control). RESULTS: Weight loss averaged 7.6% in the CR and 9.1% in the CR+EX group (time effect, p < 0.001; group effect, p = 0.11); insulin sensitivity improved by 49 and 45%, respectively (both p < 0.001). Fitness (maximal oxygen consumption) increased by 19% in the CR+EX group only (p < 0.001). Alanine aminotransferase (ALT) levels decreased by 20% in the CR and 24% in the CR+EX group (time effect, both p < 0.001; group effect, p = 0.68); corresponding values for γ-glutamyltransferase (GGT) were -28 and -33%, respectively (time effect, both p < 0.001; group effect, p = 0.28). Reduction in abdominal fat mass (measured by DXA from L1 to L4) independently predicted ΔALT (r = 0.42, p = 0.005) and ΔGGT (r = 0.55, p < 0.001), whereas change in dietary saturated fat intake was independently associated with ΔALT (r = 0.35, p = 0.03). CONCLUSIONS: Reductions in central adiposity and saturated fat intake are key drivers of improvement in liver enzymes during lifestyle interventions. Exercise training did not confer significant incremental benefits in this study.

Mediators of target organ damage in hypertension: focus on obesity associated factors and inflammation.

Arterial hypertension represents a major cardiovascular epidemic in the developed and developing world. Projections out to 2025 suggest that up to 50% of the adult populations of Western countries will meet standard guideline definitions of hypertension and thus require therapeutic intervention both non-pharmacological or pharmacological. Hyper-tension is also a component of many other major comorbidities contributing to cardiovascular disease burden. These include obesity, the metabolic syndrome, hyperlipidaemia, diabetes, and chronic kidney disease (CKD). Downstream consequences initially presenting as target organ damage of various degrees include coronary artery disease, cerebrovascular disease, nephropathy and chronic heart failure. Although elevated blood pressure per se is undoubtedly the major factor contributing to hypertensive target organ damage there is clear evidence that other mediators are also crucially involved in the transition from a healthy to a diseased state of target organs in the clinical setting of elevated blood pressure. This has obvious consequences for a multifactorial approach aimed not only at achieving target blood pressure levels but also at preventing the development or the progression of target organ damage in order to optimally reduce the overall cardiovascular risk for patients. The epidemic we are currently facing in regards to obesity is closely associated with the expected increase in the prevalence of hypertension. A closer look into the role of obesity and associated factors for the rise in blood pressure and their role in target organ damage is therefore inevitable. This review will thus focus on the clinically important aspects of target organ damage associated with hypertension, particularly obesity related hypertension, and the evidence for the involvement of neurohormonal activation and inflammatory pathways.

Rapid potentiation of endothelium-dependent vasodilation by estradiol in postmenopausal women is mediated via cyclooxygenase 2.

Estrogens influence cardiovascular function through direct and indirect effects and via genomic and nongenomic mechanisms. The pathways underlying the nongenomic mechanisms are not completely understood. Estrogen-induced responses in vascular cells have been shown to influence prostaglandins and cyclooxygenase (COX), a key enzyme in the production of prostaglandins, with two isoforms, COX-1 and COX-2. We investigated the effects of prostaglandins on the acute potentiation by 17beta-estradiol (E) of acetylcholine (ACh)-mediated vasodilation in the cutaneous vasculature. Using a double-blind placebo-controlled design, we assessed skin blood flow in 32 healthy, postmenopausal women by laser Doppler velocimetry with direct current iontophoresis of ACh and sodium nitroprusside before and after 6-wk treatment periods with aspirin (a nonspecific COX-1 and COX-2 inhibitor), diclofenac (predominantly a COX-2 inhibitor, which also inhibits COX-1), celecoxib (a specific COX-2 inhibitor), given at anti-inflammatory doses, or placebo. Blood flux values before iontophoresis of ACh did not differ between the treatment groups or after E administration, excluding a direct cutaneous vasodilator effect of the treatments or of E. Acute E administration enhanced the response to ACh after aspirin, diclofenac, and placebo; however, this effect was completely abolished with celecoxib treatment (P < 0.05). E had no effect on sodium nitroprusside-mediated vasodilation after any of the treatments. We conclude that the COX-2 pathway plays a specific role in the rapid E-induced potentiation of cholinergic vasodilation in postmenopausal women.