Serum adiponectin and cortisol levels are not affected by studied ADIPOQ gene variants: Tehran lipid and glucose study

Association study between adiponectin gene variants, serum levels and the risk of type 2 diabetes in Tunisian women: Insights from BMI stratification

Although prior studies have shown that adiponectin synthesis is genetically determined and that its levels influence susceptibility to T2D, the results in this regard have been inconsistent. This study aims, to investigate the relationship between adiponectin gene variants with the risk of developing T2D among Tunisian women and in relation to their BMI status. A cohort of 491 Tunisian T2D women and 373 non-diabetic subjects participated in the study. Nine ADIPOQ variants namely rs16861194, rs17300539, rs266729, rs822395, rs822396, rs2241766, rs1501299, rs2241767 and rs3774261 were selected and genotyped using the TaqMan® SNP genotyping assay. Fasting serum adiponectin levels were quantified using ELISA. The results showed that only the rs17300539 variant exhibited a significant association with the risk of T2D. However, upon considering T2D group stratification based on BMI (normal weight [18-24.99 Kg/m2], overweight [25-29.99 Kg/m2] and obese [30-34.99 Kg/m2]), the ADIPOQ rs2241766 variant emerged as a contributing risk factor for increased BMI in obese women with T2D. Linear regression analysis revealed that the minor allele (A), (GA) and (AA) genotypes of rs17300539 as well as the (G) allele and (GG) genotype of rs2241766 were significantly associated with hypoadiponectinemia in T2D subjects. Two haplotypes namely GGCAATGAA and AGCCGTGGA, were identified as conferring a higher risk of T2D with the GGCAATGAA haplotype also correlating with hypoadiponectinemia. Our study underscores the importance of the rs17300539 variant and the GGCAATGAA haplotype in the risk of T2D and hypoadiponectinemia. Additionally, the presence of the rs2241766 variant highlights its association with 'diabesity' and hypoadiponectinemia among Tunisian T2D women.

Comparison of Adiponectin Levels in Anorexia Nervosa, Bulimia Nervosa, Binge-Eating Disorder, Obesity, Constitutional Thinness, and Healthy Controls: A Network Meta-Analysis

Adiponectin is a protein hormone that is produced and secreted primarily by adipose tissue. The levels of adiponectin in those with eating disorders, obesity, and healthy controls have been extensively studied. However, the general picture of the differences in adiponectin levels across the mentioned conditions is still unclear and fragmented. In this study, we pooled previous studies and performed a network meta-analysis to gain a global picture of comparisons of adiponectin levels across eating disorders, obesity, constitutional thinness, and healthy controls. Electronic databases were searched for anorexia nervosa, avoidant restrictive food intake disorder, binge-eating disorder, bulimia nervosa, healthy controls, night eating syndrome, obesity, and constitutional thinness in studies where adiponectin levels were measured. A total of 4262 participants from 50 published studies were included in the network meta-analysis. Adiponectin levels were significantly higher in participants with anorexia nervosa than in healthy controls (Hedges' g = 0.701, p < 0.001). However, adiponectin levels in constitutionally thin participants were not significantly different from those of healthy controls (Hedges' g = 0.470, p = 0.187). Obesity and binge-eating disorder were associated with significantly lower adiponectin levels compared to those of healthy controls (Hedges' g = -0.852, p < 0.001 and Hedges' g = -0.756, p = 0.024, respectively). The disorders characterized by excessive increases or decreases in BMI were associated with significant changes in adiponectin levels. These results suggest that adiponectin may be an important marker of severely disequilibrated homeostasis, especially in fat, glucose, and bone metabolisms. Nonetheless, an increase in adiponectin may not simply be associated with a decrease in BMI, as constitutional thinness is not associated with a significant increase in adiponectin.

Effect of Genetic Variations in the ADIPOQ Gene on Susceptibility to Type 2 Diabetes Mellitus

BACKGROUND

ADIPOQ (adiponectin) affects fatty acid oxidation, glucose uptake, and glycogenesis, all of which are involved in the development of diabetes. As a result, ADIPOQ is being studied as a potential gene for type 2 diabetes mellitus (T2DM), which is a polygenic disease with genetic inheritance. This study aims to investigate the genetic variants (rs17846866 and rs1501299) in ADIPOQ gene with T2DM in the Saudi population.

METHODS

In this study, T2DM patients (n=96) and healthy controls (n=96) were recruited for molecular analysis for rs17846866 and rs1501299 single nucleotide polymorphisms (SNPs). Clinical data were analyzed using t-tests, HWE analysis, and genotype and allele frequencies were calculated for the rs17846866 and rs1501299 SNPs between T2DM cases and controls. ANOVA analysis was also used to investigate the relationship between the SNPs rs17846866 and rs1501299 and T2DM characteristics.

RESULTS

The current study results confirmed a positive association between clinical characteristics, HWE analysis, genotype, and allele frequencies in both rs17846466 and rs1501299 SNPs (p<0.05). In T2DM patients, ANOVA analysis with rs17846466 and rs1501299 SNPs in the ADIPOQ gene has no effect on any of the involved parameters (p>0.05).

CONCLUSION

This study concludes as rs17846866 and rs1501299 SNPs were strongly associated in the Saudi population with T2DM patients.