Adiponectin gene SNP276 variants and central obesity confer risks for hyperglycemia in indigenous Taiwanese

Single Nucleotide Polymorphism at +276 G>T of the Adiponectin Gene and Plasma Adiponectin Level in Myanmar Type 2 Diabetic Patients

Objective

The aim of the study was to investigate the association between single nucleotide polymorphisms (SNP) at rs 1501299 (SNP+276 G>T) of the adiponectin gene and plasma adiponectin levels in type 2 diabetes mellitus (T2DM) patients in Myanmar.

Methodology

One hundred T2DM patients and 104 non-diabetic subjects were included in this cross-sectional analytical study. Genotype frequencies were determined by polymerase chain reaction - restriction fragment length polymorphism (PCR-RFLP) method. Plasma adiponectin level was measured by enzyme-linked immunosorbent assay (ELISA).

Result

Genotype frequencies (GG, GT, TT) of SNP+276 in diabetic patients were 39%, 48% and 13%, respectively. The GT and TT genotypes were more frequent in T2DM patients (OR 1.98, 95% CI, 1.10-3.55; p=0.02 and OR 4.07, 95% CI, 1.34-12.3; p=0.01), respectively. The T allele of SNP+276 was significantly associated with T2DM (OR 1.96, 95% CI, 1.27-3.01; p=0.002). Mean plasma adiponectin level was significantly lower than in T2DM patients (27.41±16.7 μg/mL) compared to non-diabetic subjects (37.19±26.77 μg/mL) (p=0.002).

Conclusion

SNP+276 at rs 1501299 of the adiponectin gene was associated with type 2 diabetes and low plasma adiponectin levels in this Myanmar population.

ADIPOQ polymorphisms are associated with changes in obesity-related traits in response to aerobic training programme in women

Among genetic variants of the ADIPOQ gene +276 G>T (rs1501299) and –11377 G>C (rs266729) are the most frequently investigated polymorphisms which were described in the context of genetic conditioning for a predisposition to obesity. However, the information of polymorphisms’ potential modifying effect on obesity-related traits achieved through training procedures are still unknown. DNA was extracted from buccal cells donated by the 201 participants and genotyping was carried out using real-time PCR. The genotype distribution was examined in a group of women measured for chosen traits before and after the completion of a 12-week training programme. Our results suggest that the ADIPOQ genotypes analyzed individually or in combination can modulate training-induced body mass measurements changes: after the training programme, carriers of rs1501299 T allele and rs266729 C allele were characterized by a greater reduction in fat mass percentage (FM), fat mass, and body mass. Moreover, the ADIPOQ polymorphisms were associated with changes in lipid profile in response to training. Additionally, we showed three main effects of genotypes for the FM, LDL-C (rs266729), and TBW (rs1501299). Our study indicate that the both polymorphisms are associated with changes in obesity-related traits in response to 12-week aerobic training programme in Caucasian women. From this evidence, it could be concluded that rs1501299 G and rs266728 G variants may be considered as disadvantageous factor in the context of training-induced effects on body mass traits.

Genetic polymorphisms associated with overweight and obesity in uncontrolled Type 2 diabetes mellitus

Generally, obese and overweight individuals display higher free fatty acid levels, which stimulate insulin resistance. The combination of overweight or obesity with insulin resistance can trigger Type 2 diabetes mellitus (T2DM) and are primary contributing factors to the development of uncontrolled T2DM. Genetic polymorphisms also play an important role as they can impact a population's susceptibility to becoming overweight or obese and developing related chronic complications, such as uncontrolled T2DM. This review specifically examines the genetic polymorphisms associated with overweight and obesity in patients with uncontrolled T2DM. Particularly, gene polymorphisms in ADIPOQ (rs1501299 and rs17300539), LepR (rs1137101 and rs1045895), IRS2 (rs1805092), GRB14 (rs10195252 and rs3923113) and PPARG (rs1801282) have been associated with overweight and obesity in uncontrolled T2DM.

Association of adiponectin gene polymorphisms with an elevated risk of diabetic peripheral neuropathy in type 2 diabetes patients

OBJECTIVE

In this study, we examined the association between two adiponectin (ADPN) gene polymorphisms, +45T/G and +276G/T, and susceptibility to diabetic peripheral neuropathy (DPN) in type 2 diabetes mellitus (T2DM) patients.

METHODS

A total of 180 T2DM patients were enrolled in this study and assigned to two groups: DPN group (n=90) and non-DPN (NDPN) group (n=90). In addition, 90 healthy subjects were chosen as healthy normal control (NC). The plasma level of ADPN was quantified by ELISA method and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used for genotype analysis of the two ADPN polymorphisms, +45T/G (rs2241766) and +276G/T (rs1501299), in all the study subjects. Statistical analysis of data was performed with SPSS version 20.0 software.

RESULTS

Serum levels of ADPN were markedly reduced in the DPN group compared to NDPN and NC groups (all P<0.05). The frequencies of TT, TG and GG genotypes and the T and G alleles of T45G and G276T polymorphisms in DPN group were significantly different than the NDPN group (all P<0.05). Notably, T45G and G276T polymorphisms were associated with significantly reduced plasma levels of ADPN in DPN and NDPN groups, compared to the NC group (P<0.001). Significant difference in ADPN plasma levels were also observed between TT, TG and GG genotypes of T45G and G276T polymorphisms. Our results indicate that the T allele in +45T/G and +276G/T polymorphisms is correlated with an elevated risk of DPN in T2DM patients. Haplotype analysis showed that GG and GT haplotypes showed a negative relationship with DPN, while TG haplotype positively correlated with risk of DPN in T2DM patients (all P<0.05).

CONCLUSION

Our results show that T45G and G276T polymorphisms of ADPN are associated with a significantly elevated risk of DPN in T2DM patients, likely by down-regulating ADPN serum level.

Association between 276G/T adiponectin gene polymorphism and new-onset diabetes after kidney transplantation

BACKGROUND

New-onset diabetes after transplantation (NODAT) is a well-recognized complication of kidney transplantation and is associated with poor outcomes. Both adiponectin and chemokine ligand 5 (CCL5) proteins are related to glucose metabolism and genetic variations in their genes can lead to development of NODAT. The aim of this study was to investigate the association of adiponectin and CCL5 genes polymorphisms with NODAT in a population of Caucasian kidney transplant recipients.

METHODS

Two hundred seventy Caucasian kidney transplant recipients (83 with NODAT and 187 without NODAT) were included in a nested case-control study. Patients with pretransplantation diabetes mellitus and multiorgan transplantation were excluded. NODAT diagnosis was determined by American Diabetes Association criteria. Subjects were genotyped for 276G/T adiponectin gene polymorphism (rs1501299) and rs2280789 and rs3817655 CCL5 gene polymorphisms by real-time polymerase chain reaction.

RESULTS

The TT genotype of 276G/T adiponectin gene polymorphism was significantly more frequent in NODAT than non-NODAT patients compared with GG/GT genotypes (recessive model; P=0.031). TT genotype was identified as an independent risk factor for NODAT in Caucasian kidney transplant recipients after adjusting for age at transplantation, pretransplantation body mass index, and use of tacrolimus (TT vs. GG/GT, hazard ratio=1.88, 95% confidence interval=1.03-3.45, P=0.041). There were no differences in genotype distribution and allele frequency of rs2280789 and rs3817655 CCL5 gene polymorphisms between NODAT and non-NODAT groups.

CONCLUSIONS

The 276G/T adiponectin gene polymorphism is associated with NODAT in Caucasian kidney transplant recipients.

T45G and G276T Adiponectin Gene Polymorphisms in Primary Aldosteronism and Healthy Controls in an East Slovak Population

Metabolic complications are frequent in primary aldosteronism (PA) and adiponectin gene polymorphisms seem to confer a genetic risk for metabolic alterations. Aim of the study was to evaluate the prevalence of metabolic symptoms in patients with PA compared to controls and the prevalence of two single nucleotide polymorphisms (SNPs), T45G and G276T, in the adiponectin gene and their relationship to metabolic syndrome (MS). The study involved 47 patients with PA and 90 controls selected from general population. Body mass index (BMI), and selected biochemical parametres were examined, and the mentioned SNPs were genotyped in all subjects. PA patients had a significantly higher BMI (p0.0001), blood glucose level (p0.01), and triglycerides (p0.0005) compared to controls. There were no significant differences in the prevalence of the studied genotypes of adiponectin gene polymorphisms. The 276GT genotype was linked with lower levels of triglycerides (p≤0.05), while 276GG was related to higher levels of triglycerides (p=0.01). A similar but non-significant tendency was observed in relation to cholesterol levels. We can conclude that PA patients with the 276GT genotype have lower triglycerides levels, but there are not significant differences in the distribution of genotypes and alleles among PA patients and controls in an East Slovak population.

Amerindians show association to obesity with adiponectin gene SNP45 and SNP276: population genetics of a food intake control and "thrifty" gene

Adiponectin gene polymorphisms SNP45 and SNP276 have been related to metabolic syndrome (MS) and related pathologies, including obesity. However results of associations are contradictory depending on which population is studied. In the present study, these adiponectin SNPs are for the first time studied in Amerindians. Allele frequencies are obtained and comparison with obesity and other MS related parameters are performed. Amerindians were also defined by characteristic HLA genes. Our main results are: (1) SNP276 T is associated to low diastolic blood pressure in Amerindians, (2) SNP45 G allele is correlated with obesity in female but not in male Amerindians, (3) SNP45/SNP276 T/G haplotype in total obese/non-obese subjects tends to show a linkage with non-obese Amerindians, (4) SNP45/SNP276 T/T haplotype is linked to obese Amerindian males. Also, a world population study is carried out finding that SNP45 T and SNP276 T alleles are the most frequent in African Blacks and are found significantly in lower frequencies in Europeans and Asians. This together with the fact that there is a linkage of this haplotype to obese Amerindian males suggest that evolutionary forces related to famine (or population density in relation with available food) may have shaped world population adiponectin polymorphism frequencies.

Genetic effects of adiponectin on blood lipids and blood pressure

OBJECTIVE

Results from the published studies on the association of adiponectin gene (ADIPOQ) polymorphisms with blood lipids and blood pressure are conflicting. We investigated the association of three ADIPOQ polymorphisms, +45 T > G (rs2241766), +276 G > T (rs1501299) and -11377 C > G (rs266729), with these traits in this meta-analysis.

RESEARCH DESIGN AND METHODS

We included 35 studies in this meta-analysis. Dominant models were used for this meta-analysis.

RESULTS

We did not detect a significant association of the -11377 C > G polymorphism with blood lipids or blood pressure (P > 0·05). The association of the +45 T > G polymorphism with blood lipids and blood pressure was, similarly, not significant (P > 0·05). The meta-analysis suggested a significant overall association of the +276 G > T polymorphism with lower levels of total cholesterol: weighted mean difference (WMD) = -0·10, 95% confidence interval (CI, -0·17, -0·03), P = 0·005, P(heterogeneity)  = 0·04. This association was marginally significant in East Asians and East Asians with type 2 diabetes: WMD = -0·10, 95% CI (-0·20, 0·00), P = 0·05, P(heterogeneity)  = 0·002, and WMD = -0·09, 95% CI (-0·18, -0·00), P = 0·05, P(heterogeneity)  = 0·80, respectively. After exclusion of a study that was the source of heterogeneity, the association was significant in overall populations and marginally significant in East Asians: WMD= -0·06, 95% CI (-0·11, -0·01), P = 0·01, P(heterogeneity)  = 0·98, and WMD = -0·06, 95% CI (-0·12, 0·00), P = 0·07, P(heterogeneity)  = 0·83, respectively. However, none of these associations were significant after Bonferroni correction (significant threshold: P < 0·003).

CONCLUSIONS

Our meta-analysis does not suggest any association of the three ADIPOQ polymorphisms with blood lipids and blood pressure.

Variations in Adipokine Genes AdipoQ, Lep, and LepR are Associated with Risk for Obesity-Related Metabolic Disease: The Modulatory Role of Gene-Nutrient Interactions

Obesity rates are rapidly increasing worldwide and facilitate the development of many related disease states, such as cardiovascular disease, the metabolic syndrome, type 2 diabetes mellitus, and various types of cancer. Variation in metabolically important genes can have a great impact on a population's susceptibility to becoming obese and/or developing related complications. The adipokines adiponectin and leptin, as well as the leptin receptor, are major players in the regulation of body energy homeostasis and fat storage. This paper summarizes the findings of single nucleotide polymorphisms in these three genes and their effect on obesity and metabolic disease risk. Additionally, studies of gene-nutrient interactions involving adiponectin, leptin, and the leptin receptor are highlighted to emphasize the critical role of diet in susceptible populations.