Climacteric obesity: from genesis to clinic

Circulating adiponectin represents a biomarker of the association between adiposity and bone mineral density

An association exists between adiposity, insulin resistance, and osteoporosis; however, the mechanism of this relationship remains enigmatic. We aimed to determine whether the insulin resistance index (HOMA-IR), serum adiponectin, or leptin levels are associated with bone mineral density (BMD). A cross-sectional, observational study was designed. Eighty-four postmenopausal ambulant women [52.5 (50.0-58.0) years; body mass index (BMI): 29.4 (25.9-33.8) kg/m(2)] referred for osteoporosis screening were enrolled. Anthropometric measures, fasting serum adiponectin and leptin levels, and the HOMA-IR were determined. The relationships between these variables and lumbar, hip, and forearm BMD measured by dual-energy X-ray absorptiometry (DXA) were analyzed. Considering all 84 participants, the HOMA-IR index was 1.82 (1.17-2.86), serum adiponectin was 13.25 (10.49-16.88) microg/ml, and serum leptin was 19.26 (14.94-24.90) ng/ml. BMI, waist circumference, and leptin positively correlated with hip and lumbar BMD, whereas adiponectin negatively correlated. Multivariate analysis confirmed an inverse relation between serum adiponectin level and femoral neck and lumbar BMD measurements. In total hip and forearm areas, there was no independent association of adipocytokines with BMD measurements. Instead, waist circumference was independently associated with BMD measurements. In conclusion, adiponectin may represent a biomarker in the relationship between visceral fat mass and BMD. However, this association is probably confounded by the specific body composition parameters (i.e., waist circumference, BMI) in postmenopausal women.

beta(3)-adrenergic receptor polymorphism and metabolic syndrome in postmenopausal women

OBJECTIVES

Some studies indicate that the Trp64Arg polymorphism in the gene encoding the beta(3)-adrenergic receptor (ADRB3) is associated with obesity, insulin resistance and earlier onset of type 2 diabetes mellitus. The aim of the present study was to evaluate the frequency of ADRB3 polymorphism and its association with metabolic syndrome in postmenopausal women.

METHODS

We performed the study on 284 randomly chosen postmenopausal women, aged 50-60 years, who were then selected to the study. Measurements of anthropometric parameters and biochemical estimations such as lipid profile, glucose and insulin level in serum were carried out using commercial kits. ADRB3 genotyping was performed by polymerase chain reaction and mini-sequencing.

RESULTS

The frequency of the Trp64/Arg64 genotype in the investigated population was 13%, and of the Trp64/Trp64 genotype, 85%. The Arg64/Arg64 genotype was present in only 2% of women. Metabolic syndrome was recognized in 22% of women bearing Trp64/Arg64 genotype and in 14% of women bearing Trp64/Trp64 genotype, without a statistically significant difference between the two groups (p > 0.05 in the chi(2) test). Women bearing the Trp64/Arg64 genotype had lower serum levels of high-density lipoprotein cholesterol (HDL-C) than Trp64/Trp64 genotype women (63.2 +/- 13.0 vs. 71.4 +/- 17.4 mg/dl). Both groups did not differ in any other investigated parameter.

CONCLUSION

Trp64Arg polymorphism of the beta(3)-adrenergic receptor gene is not related to metabolic syndrome in postmenopausal Polish women; however, it seems to be associated with decreased HDL-C levels.