Association of adiponectin gene polymorphism with adiponectin levels and risk for insulin resistance syndrome

A Systematic Narrative Review on ADIPOQ Gene Variants and its Association with T2DM in the Indian Population

BACKGROUND

The prevalence of diabetes is rapidly increasing in India, even among young adult individuals. Rare adiponectin gene (ADIPOQ) variants may be predominantly present in Indians and decrease the circulatory levels of APN (Adiponectin). Studies reported that ADIPOQ gene variants were associated with type 2 diabetes mellitus (T2DM) and its complications in the Indian population.

OBJECTIVES

To review the association of specific ADIPOQ gene variants with T2DM and its associated complications.

MATERIALS & METHODS

A search of Pubmed, Chinhal, Medline, Scopus, Web of Science databases, and Google Scholar search engine was performed to retrieve articles by using the following keywords; "ADIPOQ and T2DM", "ADIPOQ and India," "ADIPOQ gene variants and T2DM", "ADIPOQ gene variants and T2DM and India", "SNPs of ADIPOQ gene and T2DM", "SNPs of ADIPOQ gene and India," SNPs of ADIPOQ gene and T2DM and India". Eligibility criteria for the inclusion of articles: Original, Case-Control Study, and Full-Text articles were published in the English language till the end of April 2023.

RESULTS

A total of 540 articles were retrieved. Out of this, only 18 articles were found suitable to include in this systematic narrative review. The most studied ADIPOQ gene variants were found to be +10211T/G (rs17846866), +45T/G (rs2241766), and +276G/T (rs1501299) in different Indian populations.

CONCLUSION

It was reviewed that ADIPOQ gene variants +10211T/G (rs17846866), +45T/G (rs2241766), and +276G/T (rs1501299) were predominantly present in the Indian population, and decreasing the circulatory levels of APN and significantly associated with T2DM and its complications.<.

Functional Haplotypes in the ADIPOQ Gene are Associated with Underweight, Immunosuppression and Viral Suppression in Kenyan HIV-1 Infected Antiretroviral Treatment Naive and Experienced Injection Substance Users

Background

Human immunodeficiency virus and injection substance use have an influence on genes and gene expression. These effects could be beneficial or detrimental in defining disease outcomes. Adiponectin gene is key in modulating metabolic and immunoregulatory functions. Understanding the effects of human immunodeficiency virus and injection substance use on the gene in the context of antiretroviral therapy is important for predicting disease outcomes.

Methods

This cross-sectional genetic study determined polymorphisms in the promoter region of adiponectin gene. Two variants were analyzed: rs2241766 and rs266729. Polymorphisms were associated with clinical markers of disease outcome; underweight, immunosuppression and viral suppression. The variants were genotyped via random fragment length polymorphism.

Result

GC haplotype was associated with higher odds of having underweight (OR, 2.21; 95% CI, 1.83-4.60; P=0.008 vs. OR, 2.30; 95% CI, 1.89-4.71; P=0.006) in antiretroviral treatment - naive and experienced injection substance users and immunosuppression (OR, 1.90; 95% CI 1.67-3.98, P=0.041) in naive. Bonferroni correction revealed GC haplotype carriers only to have low body mass index in both naive (median, 14.8; IQR, 3.2 kg/m²; P=0.002) and experienced (median, 15.2; IQR, 3.2 kg/m²; P=0.002) injection substance users. Circulating total adiponectin levels were higher in naive (median, 19.5; IQR, 7.9 µg/ml) than - experienced (median, 12.0; IQR, 4.4 µg/ml) injection substance users (P=0.0001). GC carriers presented with low serum adiponectin levels in both study groups.

Conclusion

The study revealed haplotypes of adiponectin gene at loci rs2241766 and rs266729 that could determine disease outcomes in human immunodeficiency virus -1 antiretroviral treatment- naive and experienced injection substance users.

Association of ADIPOQ rs266729 and rs1501299 gene polymorphisms and circulating adiponectin level with the risk of type 2 diabetes in a population of Iran: a case-control study

Purpose

Mutation in various regions of the adiponectin (ADIPOQ) gene is described to be associated with type 2 diabetes (T2D). Our aim was to investigate the association between rs1501299 (SNP + 276 G > T) and rs266729 (SNP-11377 C > G) polymorphisms of ADIPOQ gene and susceptibility to T2D in an Iranian population.

Methods

This is a case-control study. A total of 210 subjects including 100 patients with T2D and 110 healthy controls were selected from an Iranian population. SNP-11377 C > G and SNP + 276 G > T polymorphisms were investigated using the Tetra ARMS-PCR method.

Results

The genotypes frequency of the SNP-11377 C > G polymorphism (P = 0.21) and SNP + 276 G > T polymorphism (P = 0.10) were in agreement with the Hardy-Weinberg equilibrium. The genotype and allele frequencies for rs266729 polymorphism showed a significant difference between the T2D and control groups. Further, the frequencies of the genotypes of GG (OR = 2.43, P = 0.031), GG + GG (OR = 2.11, P < 0.01) and G allele (OR = 1.6, P = 0.041) in SNP-11377 C > G polymorphism was significantly associated with an increased risk of T2D compared to control group. While, there was no significant association between the different genotypes of SNP + 276 G > T polymorphism and the risk of T2D in an Iranian population. The circulating adiponectin level in T2D subjects had significant difference compared to the control group in rs266729 polymorphism.

Conclusion

We concluded that ADIPOQ rs266729 (SNP-11377 C > G) gene polymorphism but no rs1501299 is associated with increased risk of T2D in our population.

Association between carriers of the G allele of the + 45T> G variant of the ADIPOQ gene (rs 2241766) and the cardiometabolic profile in sickle cell trait

AIMS

investigate the association between the +45T > G variant of the ADIPOQ gene and the metabolic syndrome (MS) in patients with sickle cell trait (SCT). 33 patients with SCT and 35 control group participated in the study. Lower levels of HDL and adiponectin were observed in patients with G allele and sickle cell trait. There were no differences between the prevalence of MS between the groups and there was no association between the +45T > G variant of the ADIPOQ gene and MS risk allele.

MATERIALS AND METHODS

Participants with and without sickle cell anemia answered a questionnaire, performed anthropometric and laboratory analyzes. They were genotyped for the +45T > G variant of the ADIPOQ gene and evaluated for the presence or absence of metabolic syndrome. The study was approved by the Research Ethics Committee of UNIPAMPA (RS/Brazil).

KEY FINDINGS

The GG + TG genetic model, it was associated with lower levels of adiponectin and HDL cholesterol in the SCT group. There was no association between the other studied markers and MS.

SIGNIFICANCE

For the first time, an association was demonstrated between the G allele of the +45T > G variant of the ADIPOQ gene and a worse cardiometabolic profile (lower serum concentrations of adiponectin and HDL cholesterol) in patients with sickle cell trait.

Association between adiponectin rs17300539 and rs266729 gene polymorphisms with serum adiponectin level in an Iranian diabetic/pre-diabetic population

OBJECTIVE

Adiponectin is an adipokine that is mostly secreted from adipose tissues and has a significant role in the improvement of insulin resistant and type 2 diabetes mellitus (T2DM). This study is conducted to examine the association of rs17300539 and rs266729 with T2DM and serum adiponectin level in Iranian population.

METHOD

A case-control study was conducted on 80 individuals with fasting plasma glucose (FPG) >100 (mg/dl) as diabetic-pre-diabetic group, and 80 individuals with fasting plasma glucose 70-100 (mg/dl) as control group. DNA extraction was done on samples and genotyping method was performed by PCR-RFLP.

RESULT

The frequency of GA genotype in rs17300539 (diabetic/pre-diabetic 35.5%, control 11.3%, (OR [95%CI]=4.18[1.8-9.6]; p=0.001) and allele A (diabetic/pre-diabetic 31%, control 9%, (OR [95% CI]=4.67[2-10.7]) was significantly more in diabetic/pre-diabetic group compared to control group. The difference in the genotype frequency for rs266729 in diabetic group compared to that in control was not significant. The levels of adiponectin in diabetic cases had no difference compared to the control group in both polymorphisms. The rs266729 was not associated with any metabolic parameter except waist circumference (p=0.03), however, rs17300539 shows association only with fasting plasma glucose, triglyceride, and total cholesterol (p=0.007, 0.039, 0.0032, respectively).

CONCLUSION

Our findings showed that there is an association between rs17300539 with the increase of T2DM but rs266729 showed no association with the risk of T2DM. Allele A of rs17300539 increased the risk of diabetes. There is no association between adiponectin level and both polymorphisms.

Leptin gene variants and colorectal cancer risk: Sex-specific associations

BACKGROUND

High levels of serum leptin and low levels of serum adiponectin are strongly correlated with obesity, a well-established risk factor for colorectal cancer (CRC). Growing evidence suggests that dysregulation of leptin and adiponectin levels may play an etiological role in colorectal carcinogenesis. We evaluated 20 candidate variants in 4 genes previously shown to alter serum leptin and adiponectin levels for associations with obesity (BMI>30 kg/m2) and CRC risk.

METHODS

We analyzed 6,246 CRC cases and 7,714 population-based controls from 11 studies within the Genetics and Epidemiology of Colorectal Cancer Consortium (GECCO). Associations of each variant with obesity or CRC were evaluated using multivariate logistic regression models stratified by sex and adjusted for age, a study variable, and the first three principal components of genetic ancestry. Gene-specific False Discovery Rate (FDR)-adjusted p-values <0.05 denoted statistical significance.

RESULTS

Two variants in the leptin gene showed statistically significant associations with CRC among women: LEP rs2167270 (OR = 1.13, 95% CI: 1.06-1.21) and LEP rs4731426 (OR = 1.09, 95% CI: 1.02-1.17). These associations remained significant after adjustment for obesity, suggesting that leptin SNPs may influence CRC risk independent of obesity. We observed statistically significant interactions of the leptin variants with hormone replacement therapy (HRT) for CRC risk; these variant associations were strengthened when analyses were restricted to post-menopausal women with low estrogen exposure, as estimated by 'never use' of HRT and/or non-obese BMI. No variants were associated with CRC among men.

CONCLUSIONS

Leptin gene variants may exhibit sex-specific associations with CRC risk. Endogenous and exogenous estrogen exposure may modify the association between these variants, leptin levels, and CRC risk.

Genetic association of ADIPOQ gene variants (-3971A>G and +276G>T) with obesity and metabolic syndrome in North Indian Punjabi population

BACKGROUND AND AIMS

At present obesity and metabolic syndrome (MetS) in India are the most challenging health problems. It is also well accepted that obesity is a significant risk factor for the development of metabolic syndrome and other degenerative diseases. Many studies have reported that single-nucleotide polymorphisms (SNPs) of the adiponectin (ADIPOQ) gene have been associated with obesity and its related disorders. Here, we aimed to investigate the association of two intronic variants in ADIPOQ gene, -3971A>G (rs822396) and +276G>T (rs1501299) with obesity and metabolic syndrome.

METHODS

Biochemical and anthropometric measurements were obtained from a total of 550 unrelated subjects (obese = 250 and non-obese = 300) of North Indian Punjabi population. Genotyping for the intron variants were performed by polymerase chain reaction based restriction fragment length polymorphism (PCR-RFLP) methods. After genotyping, as a quality control measure 10% of the samples for each polymorphism were confirmed by Sanger Sequencing method. The distributions of genotypic and allelic frequencies among obese and non-obese groups were compared by chi-square test and the corresponding risk was calculated using binary logistic regression. The effects of multiple testing were controlled by applying Bonferroni corrections.

RESULTS

All the anthropometric and biochemical parameters except triglycerides (TG) and very low-density lipoproteins cholesterol (VLDL-C) have shown significant association with both GG and TT genotypes of -3971A>G (rs822396) and +276G>T (rs1501299) polymorphisms respectively. The frequencies of GG (-3971A>G) and TT (+276G>T) genotypes were higher among obese cases (p = 0.008 and p = 0.035 respectively). However, no significant association was found between allelic frequencies of ADIPOQ rs822396 and obesity, whereas the association of ADIPOQ rs1501299 attenuated and became marginally significant after Bonferroni correction (p>0.025). Both the variant genotypes of ADIPOQ gene polymorphisms (-3971GG and +276TT) significantly increased the risk of development of obesity (OR: 1.52, p = 0.03; OR: 1.58, p = 0.04 respectively) and MetS (OR: 1.42, p = 0.03; OR: 1.57, p = 0.01 respectively) in the present population, after adjusting the various covariates. The G-T haplotype model (possessing -3971G and +276T alleles) was shown toprovide ~ 3 fold risk towards the obesity susceptibility (OR: 2.69, p = 0.009) and MetS risk (OR: 2.73, p = 0.009) and the association persisted after adjusting for different confounding variables.

CONCLUSION

The present study has confirmed that ADIPOQ -3971A>G (rs822396) and +276G>T (rs1501299) polymorphism may be clinically helpful to estimate obesity and MetS risk in North Indian Punjabi population.

Association of Adiponectin 45T/G Polymorphism with Diabetic Cardiovascular Complications in Korean Type 2 Diabetes

BACKGROUND

Adiponectin is an adipokine that regulates lipid and glucose metabolism and has been shown to have anti-inflammatory and anti-atherogenic effects. It also plays an important role in the development of cardiovascular disease (CVD).

METHODS

This study evaluated the association between adiponectin 45T/G polymorphism and cardiovascular complication in type 2 diabetes in Koreans.

RESULTS

The present study included 758 patients with type 2 diabetes. The distribution of the adiponectin 45T/G polymorphism was 3.56% (n = 27) for GG, 42.35% (n = 321) for TG, and 54.09% (n = 410) for TT in patients with type 2 diabetes. The prevalence of CVD was significantly higher in subjects with the GG + TG genotype compared to those with the TT genotype (17.5% vs. 9.8%, P = 0.002). The G allele was associated with a higher risk of CVD (P = 0.002).

CONCLUSION

Our findings suggest that the adiponectin 45T/G polymorphism is associated with diabetic cardiovascular complication in type 2 diabetes.

Single Nucleotide Polymorphisms in Adiponectin Gene Are Not Directly Associated with Increased Risk of Obstructive Sleep Apnea Syndrome in a Chinese Han Population

PURPOSE

This study aims to test the possible correlation between single nucleotide polymorphisms (SNPs) in the adiponectin gene and increased risk of obstructive sleep apnea syndrome (OSAS) in a Chinese Han population.

MATERIALS AND METHODS

A total of 266 subjects were enrolled into the study to detect 9 SNPs in the adiponectin gene. Multivariate unconditional logistic regression analysis, adjusted for gender and age, was used to estimate the associations of these SNPs with OSAS risk.

RESULTS

No evidence of a direct association was observed between these SNPs and the risk of OSAS in the Chinese Han population. However, the stratified analysis also revealed a remarkable genotype difference for SNP rs6773957 between cases and controls in the overweight subgroup (p < 0.05). In addition, the allele or genotype distributions of rs12495941, rs182052, and rs16861205 had significant differences with regard to the severity of OSAS (p < 0.05). No differences were identified in the other subgroups.

CONCLUSION

The current research demonstrated that the SNPs in the adiponectin gene did not represent susceptibility loci for OSAS in Chinese Han individuals overall. However, variants of rs6773957 have an association with OSAS in overweight individuals. In addition, polymorphisms of rs12495941, rs182052, and rs16861205 are associated with the severity of OSAS.

Association of Adiponectin Polymorphism with Metabolic Syndrome Risk and Adiponectin Level with Stroke Risk: A Meta-Analysis

Many previous studies have provided evidence that the ADIPOQ +45T>G polymorphism (rs2241766) might cause metabolic syndrome (MS). As a cardiovascular manifestation of MS, the incidence of stroke is associated with adiponectin; however, the results remain controversial and inconsistent. Systematic searches of relevant studies published up to Dec 2014 and Jan 2016 on the ADIPOQ +45T>G polymorphism and the risk of MS and adiponectin levels and the risk of stroke, respectively, were conducted in MEDLINE and EMBASE. The odds ratio (OR) or risk ratio (RR) and their 95% confidence interval (95% CI) were extracted. Sixteen studies containing 4,113 MS cases and 3,637 healthy controls indicated a weak positive association between ADIPOQ +45 T>G and MS in the dominant genetic model (OR = 1.30, 95% CI = 1.03-1.65), which was also validated by stratified subgroup analyses. Twelve studies including 26,213 participants and 4,246 stroke cases indicated that 5 μg/ml increments in adiponectin level were not relevant to stroke risk (RR = 1.05, 95% CI = 1.00-1.10, P = 0.069). This study suggested a weak positive association of ADIPOQ +45T>G with MS and a strong association with metabolic-related disease. Additionally, adiponectin level was not a causal factor of increasing stroke risk.