Drug combinations for dyslipidemia and obesity treatment in metabolic syndrome

Differential effect of oral dehydroepiandrosterone-sulphate on metabolic syndrome features in pre- and postmenopausal obese women

OBJECTIVE

To analyze the effect in obese pre- and postmenopausal women of a daily dose of 100 mg dehydroepiandrosterone-sulphate (DHEA-S) provided over a period of 3 months as replacement therapy against metabolic syndrome.

CONTEXT

Although DHEA-S appears to be effective against certain features of metabolic syndrome, its usefulness against this syndrome as a whole has not been evaluated to date.

DESIGN/PATIENTS

A randomized, double-blind placebo-controlled trial was conducted involving 61 postmenopausal women, who received DHEA-S (n = 41) or placebo (n = 20) for 3 months. The effect of DHEA-S treatment on the same postmenopausal women was compared with the effects observed in a group of premenopausal women (n = 20).

MEASUREMENTS

Anthropometric measurements were taken at the beginning and at the end of the treatment. Similarly, different parameters that define metabolic syndrome and other cardiometabolic variables were determined.

RESULTS

Dehydroepiandrosterone-sulphate replacement produced weight loss in the obese women studied. Moreover, waist circumference, glucose and systolic and diastolic blood pressure, among other metabolic syndrome parameters, improved in the postmenopausal group, who showed a significant reduction in the total metabolic syndrome score (P < 0·05). In contrast, in premenopausal women, the effect of DHEA-S was limited to obesity parameters, and no effect was observed on metabolic syndrome components. No significant changes were evident in the placebo group.

CONCLUSIONS

An oral dose of DHEA-S is useful for weight loss. In obese postmenopausal women, the hormone significantly improves plasma biochemical levels and anthropometric characteristics, leading to a better metabolic profile, which highlights the usefulness of this therapy against metabolic syndrome in this group of women.

Enhanced fatty acid flux triggered by adiponectin overexpression

Adiponectin overexpression in mice increases insulin sensitivity independent of adiposity. Here, we combined stable isotope infusion and in vivo measurements of lipid flux with transcriptomic analysis to characterize fatty acid metabolism in transgenic mice that overexpress adiponectin via the aP2-promoter (ADNTg). Compared with controls, fasted ADNTg mice demonstrated a 31% reduction in plasma free fatty acid concentrations (P = 0.008), a doubling of ketones (P = 0.028), and a 68% increase in free fatty acid turnover in plasma (15.1 ± 1.5 vs. 25.3 ± 6.8 mg/kg · min, P = 0.011). ADNTg mice had 2-fold more brown adipose tissue mass, and triglyceride synthesis and turnover were 5-fold greater in this organ (P = 0.046). Epididymal white adipose tissue was slightly reduced, possibly due to the approximately 1.5-fold increase in the expression of genes involved in oxidation (peroxisome proliferator-activated receptor α, peroxisome proliferator-activated receptor-γ coactivator 1α, and uncoupling protein 3). In ADNTg liver, lipogenic gene expression was reduced, but there was an unexpected increase in the expression of retinoid pathway genes (hepatic retinol binding protein 1 and retinoic acid receptor beta and adipose Cyp26A1) and liver retinyl ester content (64% higher, P < 0.02). Combined, these data support a physiological link between adiponectin signaling and increased efficiency of triglyceride synthesis and hydrolysis, a process that can be controlled by retinoids. Interactions between adiponectin and retinoids may underlie adiponectin's effects on intermediary metabolism.

Naltrexone sustained-release (SR) + bupropion SR combination therapy for the treatment of obesity: 'a new kid on the block'?

The prevalence of obesity is growing rapidly worldwide, and therefore there is a need for effective treatment strategies. The rationale of combination therapy in treating chronic diseases, such as obesity, is the potential additive or synergistic effects. This review considers the results of phase III clinical trials with naltrexone sustained-release (SR) + bupropion SR combination therapy in obese patients with or without type 2 diabetes mellitus. We also discuss the potential therapeutic applications of this weight-reducing treatment option. Recent clinical trials have shown that the administration of naltrexone SR + bupropion SR resulted in effective weight loss. Furthermore, this treatment was associated with improvement in cardiometabolic variables. Depression and suicidal ideation were more frequently reported in the placebo compared with the combination groups. However, significantly more patients on naltrexone SR + bupropion SR experienced adverse events, mainly nausea, and discontinued treatment compared with placebo. Increases in blood pressure and pulse rate were observed only in the combination groups. Further investigation is needed to clarify the clinical significance of this weight-reducing therapeutic option.