Metabolic Syndrome Components in a Nondiabetic Afro-Caribbean Population: Influence of Gender and Age.

Background: Our aim was to describe the prevalence of metabolic syndrome (MetS) and its components among Afro-Caribbean adults without diabetes and cardiovascular complications. Methods: Participants were recruited from a Health Center in Guadeloupe, French West Indies. MetS was defined according to the NCEP ATP III. Prevalence of MetS and MetS components were compared across age groups and sex. The odds ratios (ORs) and 95% confidence intervals were obtained using logistic regression. Results: There were 1011 participants (68.8% women, mean age 47.8 ± 11.8 years). Prevalence of MetS was 17.9% (21.1% women, 10.8% men) and increased by age in women. High blood pressure had the highest prevalence among men and among women ≥60 years. Prevalence of abdominal obesity (AbO) was higher in women than in men. High triglyceride levels were uncommon at all ages and, men and women <40 years, compared with the other groups had higher prevalence of low high-density lipoprotein cholesterol (HDL-C) levels. With multiple logistic regression, compared with adults <40 years, those ≥60 years had the highest OR for prevalent hypertension 7.8 (4.8-12.8); P < 0.001, AbO 2.1 (1.3-3.3); P = 0.002 and high fasting blood glucose levels 5.5 (3.1-9.8); P < 0.001. They also had lower odds for having low HDL-C than the younger ones (G1: age <40 years). Among persons ≥60 years, OR for MetS was 1.9 (1.1-3.6); P = 0.013 compared with the referent group. Compared with men, women had higher odds of MetS 2.2 (1.5-3.3); P < 0.001. Conclusion: Women were more likely to have MetS than men and persons ≥60 years were significantly more likely to have MetS than persons <40 years. Preventive measures are required to reduce the prevalence of MetS.

N-terminal Pro-B-Type Natriuretic Peptide and Malnutrition in Patients on Hemodialysis.

Natriuretic peptides, brain natriuretic peptide (BNP), and N-terminal probrain natriuretic peptide (NT-proBNP) are mainly known as diagnostic markers for heart failure with high diagnostic and prognostic values in the general population. In patients who are undergoing hemodialysis (HD), changes in NT-proBNP can be related to noncardiac problems such as fluid overload, inflammation, or malnutrition and can also be influenced by the dialysis characteristics. The current review aimed to summarize findings from studies on the association between NT-proBNP and malnutrition in HD patients. Articles published after 2009 and over a ten-year period were considered for inclusion. We first briefly discuss the traditional functions of NT-proBNP, and after, we describe the functions of this prohormone by focusing on its relation with protein energy wasting (PEW) in HD patients. Mechanisms that could explain these relationships were also discussed. Overall, 7 studies in which the investigation of the relations between NT-proBNP and nutritional status in HD patients were among the main objects were taken into account. NT-proBNP levels correlated with several factors described in the 4 categories of markers indicative of PEW (body mass and composition, muscle mass, biochemical criteria, and dietary intakes) and/or were associated with PEW. Interactions between several parameters could be involved in the association between NT-proBNP and malnutrition with a strong role of weight status. NT-proBNP is elevated in HD patients and is associated with malnutrition. Nevertheless, the prognostic value of NT-proBNP on nutritional status should be evaluated.

Influence of K656N Polymorphism of the Leptin Receptor Gene on Obesity-Related Traits in Nondiabetic Afro-Caribbean Individuals.

Background: Ethnic variations have been reported in allelic frequencies of the leptin receptor gene (LEPR) with population-specific effects. We aimed to explore the association of LEPR polymorphisms with obesity, metabolic syndrome (MetS), and leptin levels in Afro-Caribbean nondiabetic subjects. Methods: Genotypic analysis of three LEPR polymorphisms (K109R, Q223R, and K656N) was performed using TaqMan allelic discrimination assays. Associations were measured with phenotypic variables, including body mass index (BMI), waist circumference (WC), and leptin levels. Linear and logistic regressions were performed to evaluate the effects of single-nucleotide polymorphisms (SNPs). Results: Mean age was 46 ± 12 years. Among the 375 participants, 29.3% were obese, 36.3% had abdominal obesity, and 18.1% had MetS. Significant association between BMI (P < 0.002) and WC (P < 0.005) was observed for K656N, whereas the associations were not statistically significant for the other two SNPs. No association was found with leptin levels for the three SNPs. The variant allele frequencies for LEPR 109R, 223R, and 656N were 0.16, 0.46, and 0.20, respectively. In dominant models, the variant allele 656N (GC/CC vs. GG) was associated with prevalence of obesity [odds ratio (OR) 1.82; P = 0.012] and abdominal obesity (OR 2.00; P = 0.007), but not significantly with prevalence of MetS (OR 1.72; P = 0.029). Individuals carrying four variant alleles of the three SNPs had a significantly higher risk of obesity (OR 2.86; P = 0.032) than those carrying none variant allele. Conclusion: Our results suggest an influence of K656N polymorphism in the LEPR gene on obesity and abdominal obesity in this Afro-Caribbean population.

Metabolic remodelling of cardiac myocytes during pregnancy: the role of mineralocorticoids.

BACKGROUND: Pregnancy is associated with significant cardiac adaptations. The regulatory mechanisms involved in functional cardiac adaptations during pregnancy are still largely unknown. In pathologic conditions, mineralocorticoids have been shown to mediate structural as well as functional remodelling of the heart. However, their role in cardiac physiological conditions is not completely understood. Here, we examined cardiac cell metabolic remodelling in the late stages of rat pregnancy, as well as mineralocorticoid involvement in this regulation. METHODS: We have applied rapid video imaging, echocardiography, patch clamp technique, confocal microscopy, and time-resolved fluorescence spectroscopy. RESULTS: Our results revealed that cardiac cells undergo metabolic remodelling in pregnancy. Inhibition of mineralocorticoid receptors during pregnancy elicited functional alterations in cardiac cells: blood levels of energy substrates, particularly lactate, were decreased. As a consequence, the cardiomyocyte contractile response to these substrates was blunted, without modifications of L-type calcium current density. Interestingly, this response was associated with changes in the mitochondrial metabolic state, which correlated with modifications of bound reduced nicotinamide adenine dinucleotide (phosphate) NAD(P)H levels. We also noted that mineralocorticoid receptor inhibition prevented pregnancy-induced decrease in transient outward potassium current. CONCLUSIONS: This study demonstrates that in pregnancy, mineralocorticoids contribute to functional adaptations of cardiac myocytes. By regulating energy substrate levels, in particular lactate, in the plasma and metabolic state in the cells, mineralocorticoids affect the contractility responsiveness to these substrates. In the future, understanding cardiac adaptations during pregnancy will help us to comprehend their pathophysiological alterations.