Association of adiponectin gene polymorphism rs266729 with type two diabetes mellitus in Iraqi population. A pilot study

Association of ADIPOQ Gene Polymorphisms with Type 2 Diabetes and Obesity Risk in the Kazakh Population: A Case-Control and Population-Based Study

Type 2 diabetes mellitus (T2DM) is a socially significant disease with increasing prevalence worldwide. It is characterized by heterogeneous metabolic disorders and is associated with various risk factors, including BMI, abnormal lipid levels, hypertension, smoking, dietary preferences, physical inactivity, sedentary lifestyle, family history of diabetes, prediabetes or gestational diabetes, inflammation, intrauterine environment, age, sex, ethnicity, and socioeconomic status. Assessing the genetic risk of developing T2DM in specific populations remains relevant. The ADIPOQ gene, encoding adiponectin, is directly related to the risk of developing T2DM, obesity, and cardiovascular diseases. Our study demonstrated significant associations of ADIPOQ gene polymorphisms with the risk of developing T2DM and obesity, as well as with fasting glucose levels and BMI, in the Kazakh population. Specifically, rs266729 was significantly associated with T2DM and obesity in the Kazakh population, while other studied polymorphisms (rs1501299, rs2241766, and rs17846866) did not show a significant association. These findings suggest that ADIPOQ gene polymorphisms may influence T2DM risk factors and highlight the importance of genetic factors in T2DM development. However, further research in larger cohorts is needed to confirm these associations.

Association of CDKN2A/B gene polymorphisms (rs10811661 and rs2383208) with type 2 diabetes mellitus in a sample of Iraqi population

Background

Type 2 diabetes mellitus (T2DM) is chronic metabolic disorder manifested by increased blood glucose (hyperglycemia) due to pancreatic β-cell dysfunction and/or decreased sensitivity of peripheral tissue to insulin. T2DM is a multifactorial disease that may results from interaction of environmental and genetic factors.

Methods

A case–control study consisting of 400 T2DM patients in addition to 400 as control. Phenotyping as well as anthropometric data included body mass index BMI, fasting plasma glucose (FPG), serum total cholesterol, serum triglyceride, VLDL, LDL, HDL insulin levels and Homeostatic Model Assessment for Insulin Resistance HOMA-IR were estimated for the two groups. PCR–RFLP was used to carry out genotyping of CDKN2A/B gene (rs10811661 T>C and rs2383208 A>G) SNPs.

Results

For rs10811661 SNP the genotype and allele frequencies of CDKN2A/B gene for T2DM and control subjects showed that the co-dominant model in patients with the homozygous (TT) was found to be significantly (OR 2.51, 95% CI 1.47–4.24, P 0.004) higher than those in control group. In contrast, the heterozygous genotype (TC) did not reveal this significance (OR 1.14, 95% CI 0.77–2.62, P = 0.13), ANOVA test for mean comparison of biochemical markers under the co-dominant model of rs10811661 SNP genotype in CDKN2A/B gene, revealed a significant difference for insulin (P < 0.0001) and HOMA-IR (P < 0.0001) in T2DM group as compared to control one; However (rs2383208) SNP did not show any significant association with T2DM and with the measured biochemical marker at any model.

Conclusions

CDKN2A/B gene rs10811661 SNP was implicated in T2DM pathogenesis in this sample of Iraqi population also it affects insulin level in those patients, whereas the rs2383208 SNP did not impact the disease.

Associations of the Polymorphisms in ADIPOQ with Circulating Levels of Adiponectin and Lipids: A Meta-Analysis

The relationships between the rs266729, rs1501299, and rs2241766 polymorphisms in adiponectin gene (ADIPOQ) and circulating levels of adiponectin and lipids remain to be clarified. Databases including PubMed and Embase were searched for eligible studies. The random-effects model was used, and standardized mean difference (SMD) with 95% confidence interval (CI) was calculated to estimate the differences in circulating levels of adiponectin and lipids between the subjects with different genotypes. A total of 12 810, 17 319, and 21 361 subjects were identified in the analyses for the rs266729, rs1501299, and rs2241766 polymorphisms, respectively. G allele carriers of the rs266729 polymorphism had lower levels of adiponectin (SMD=-0.28, 95% CI=-0.43 to-0.12) and high-density lipoprotein cholesterol (HDL-C) (SMD=-0.10, 95% CI=-0.17 to-0.02) than CC homozygotes; T allele carriers of the rs1501299 polymorphism had higher levels of adiponectin (SMD=0.21, 95% CI=0.05 to 0.36) and HDL-C (SMD=0.09, 95% CI=0.04 to 0.15) and lower levels of triglycerides (SMD=-0.06, 95% CI=-0.12 to-0.01) than GG homozygotes; G allele carriers of the rs2241766 polymorphism had lower levels of adiponectin (SMD=-0.18, 95% CI=-0.31 to-0.05) and HDL-C (SMD=-0.12, 95% CI=-0.20 to-0.04) than TT homozygotes. This meta-analysis suggests that the rs266729, rs1501299, and rs2241766 polymorphisms of ADIPOQ are significantly associated with circulating levels of adiponectin and lipids, which may partly explain the associations between these polymorphisms and coronary artery disease.

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 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.

The association of the common fat mass and obesity associated gene polymorphisms with type 2 diabetes in obese Iraqi population

BACKGROUND & OBJECTIVES

This study investigates the association of two potential Fat mass and obesity associated gene (FTO) gene polymorphisms (rs9939609 and rs918031) as potential predictors of type 2 diabetes (T2D) in obese Iraqi population and their metabolic effects on hyperglycemia and insulin sensitivity.

MATERIALS & METHODS

The study included 400 participants with obesity & T2D, with a matching 400 obese non-diabetic cohort. Venous blood samples were collected for DNA extraction. Using specific primers and restriction enzymes, genotyping was performed to identify the various alleles for each gene. The genotype and allele frequencies determined by multinomial logistic regression analysis for FTO single nucleotide polymorphisms (rs9939609) among all the study groups.

RESULTS

There is a two-fold increase in the risk of T2D within the homozygous genotype (TT) group (OR = 2.43, CI 95% 3.57-11.2, P ≤ 0.001) as compared to the wild type (TA). In addition, there was a significantly higher level of the minor allele genotype (T) in T2D patients when compared to the control group, (P ≤ 0.001).

CONCLUSION

We conclude that the FTO rs9939609 genotype significantly affect the development of insulin resistance, therefore the future occurrence of T2D, in obese individuals.

Genetics and genomics studies in type 2 diabetes: A brief review of the current scenario in the Arab region

BACKGROUND

Type 2 diabetes (T2D) is a polygenic and multi-factorial complex disease, the challenge to find genetic markers that could explain the risk of development of this disease still remains unresolved. The Arab region is one among the populations with a high prevalence of T2D and a large number of studies have been carried out in exploring the genetic factors associated with T2D risk.

AIM

To summarize the recent developments in the Arab world based on the recent studies that had looked into genetic factors associated with the development of T2D in the Arab populations.

METHODS

A systematic literature search was conducted to identify studies published between 2015 and 2018 reporting genetic factors or polymorphisms associated with the risk of T2D in the Arab world. The online databases PubMed and Web of Science were used to perform the literature search.

CONCLUSION

The present study has evaluated 14 studies published during the year 2015-2018. Studies from Egypt, Iraq, Jordan, Oman, Qatar, Saudi Arabia, Tunisia, and United Arab Emirates had been explored studying the associations of GIPR, ADIPOQ, FTO, (GRCh38.p12), MLXIP, AKNAD1, KCNJ11 CDKAL1, CDKN2A/2B, TCF7L2, ACE, SNAP25, ELMO1, VDR, KCTD8, GABRA4 and PRKD1 genes with T2D development.

Effects of vitamin D supplementation along with endurance physical activity on lipid profile in metabolic syndrome patients: A randomized controlled trial

BACKGROUND AND OBJECTIVES

This study was conducted to determine the effects of vitamin D supplementation along with endurance physical activity on lipid profile among metabolic syndrome patients.

MATERIALS AND METHODS

In a parallel randomized placebo controlled trial, 70 metabolic syndrome patients, were randomly assigned into three groups. Biochemical tests were assessed as baseline and after 12 weeks of intervention. Statistical analysis was performed using SPSS version 20.

RESULTS

The mean vitamin D levels was increased significantly in both vitamin D and vitamin D plus physical activity groups (P value < 0.05). No significant change was observed in the placebo group. Additionally, there was a significant decrease in total cholesterol and LDL-C in vitamin D plus physical activity group (P value < 0.05). No significant differences in changes of triglycerides and HDL-C among the three groups (P value > 0.05). While, in vitamin D group a decreased in total cholesterol, HDL-C, LDL-C and increase in triglycerides were observed, but did not reach a statistically significant.

CONCLUSION

Daily supplementation of vitamin D for 12 weeks, along with moderate endurance physical activity, significantly increase vitamin D concentration and induce a significant reduction in lipid profile in metabolic syndrome patients.

Associations between three common single nucleotide polymorphisms (rs266729, rs2241766, and rs1501299) of ADIPOQ and cardiovascular disease: a meta-analysis

Background

Inconsistencies have existed in research findings on the association between cardiovascular disease (CVD) and single nucleotide polymorphisms (SNPs) of ADIPOQ, triggering this up-to-date meta-analysis.

Methods

We searched for relevant studies in PubMed, EMBASE, Cochrane Library, CNKI, CBM, VIP, and WanFang databases up to 1st July 2017. We included 19,106 cases and 31,629 controls from 65 published articles in this meta-analysis. STATA 12.0 software was used for all statistical analyses.

Results

Our results showed that rs266729 polymorphism was associated with the increased risk of CVD in dominant model or in heterozygote model; rs2241766 polymorphism was associated with the increased risk of CVD in the genetic models (allelic, dominant, recessive, heterozygote, and homozygote). In subgroup analysis, significant associations were found in different subgroups with the three SNPs. Meta-regression and subgroup analysis showed that heterogeneity might be explained by other confounding factors. Sensitivity analysis revealed that the results of our meta-analysis were stable and robust. In addition, the results of trial sequential analysis showed that evidences of our results are sufficient to reach concrete conclusions.

Conclusions

In conclusion, our meta-analysis found significant increased CVD risk is associated with rs266729 and rs2241766, but not associated with rs1501299.

Electronic supplementary material

The online version of this article (10.1186/s12944-018-0767-8) contains supplementary material, which is available to authorized users.

Comparative effects of vitamin D and vitamin C supplementations with and without endurance physical activity on metabolic syndrome patients: a randomized controlled trial

OBJECTIVE

Vitamin D and C levels have inverse relation with the metabolic syndrome components and they are used as antioxidant supplements during enduring metabolic activities. In the present study, we hypothesized that the intake of vitamin D and/or C with endurance physical activity might reduce the risk of metabolic syndrome.

METHODS

A randomized control study recruited 180 participants of both genders, aged between 30 and 50 years. The participants were assigned into six groups receiving different doses of vitamin D or vitamin C with or without physical activities. Data were collected over a period of 3 months, and the results were analyzed using SPSS version 20.

RESULTS

Variations in the effect of the supplements on various body variables including: Fasting plasma glucose, total cholesterol, low-density lipoprotein cholesterol and blood pressure, showed that vitamin D has more influence compared to vitamin C. However, vitamin D and C supplements do not have any effect on weight when consumers are undergoing endurance physical exercise. But vitamin C consumer group has more effect in waist circumference, triglyceride, and high-density lipoprotein, as compared to vitamin D consumer group.

CONCLUSION

We conclude that, consumption of vitamin D or vitamin C supplements may improves the life of metabolic syndrome patients. However, the combination of physical activities and vitamin supplements maximize the effect, and this combination should be recommended.Trial registration WHO-ICTRP IRCT20161110030823N2. Registered 01 February 2018. http://apps.who.int/trialsearch/Trial2.aspx?TrialID=IRCT20161110030823N2.

The polymorphism of rs266729 in adiponectin gene and type 2 diabetes mellitus: A Meta-Analysis

Genome-wide association studies and meta-analyses indicate that the polymorphism of rs266729 in adiponectin gene increases the risk of type 2 diabetes mellitus (T2DM); however, these study methods have not been able to identify the underlying genetic effect on the development of T2DM. A genetic model-free approach was conducted to determine the underlying genetic model of inheritance of T2DM because of rs266729 in adiponectin gene.We searched available studies on the association between the rs266729 in adiponectin gene and T2DM in accordance with the inclusion and exclusion criteria. Based on the information extracted from the studies, generalized odds ratio value (GOR) was used to evaluate whether the rs266729 polymorphism was a risk factor for T2DM. The parameter λ was calculated to estimate the genetic model, which was defined as the quotient of natural logarithm odds ratio of GC to CC divided by the natural logarithm odds ratio of GG to CC. Finally, binary logistic regression analysis was used to calculate the genetic effect of rs266729 on T2DM.Data from 7 studies were included in this meta-analysis. The total number of subjects was 12,323, comprising 5,948 cases and 6,395 controls. Mean (standard deviation) age of cases was 59.50 (11.53), and that of the controls was 53.80 (11.65), whereas the proportion of male was 40.9 and 50.0%, respectively. GOR was 1.13 (1.02, 1.25) and λ was 0.47 (0.29, 0.64). The result of logistic regression indicated that the G allele influenced the development of T2DM in the additive model, whereas the genetic effect was 1.13 (1.06, 1.19). Sources of control populations were the cause of between-study heterogeneity; nonetheless, there was no publication bias among studies.The G allele of rs266729 in adiponectin gene increases the risk of T2DM through an additive genetic model with an effect of 1.13 (1.06, 1.19).

High Molecular Weight Adiponectin Levels are Neither Influenced by Adiponectin Polymorphisms Nor Associated with Insulin Resistance in Mixed-ancestry Hyperglycemic Subjects from South Africa

Background

High molecular weight (HMW) adiponectin has antiatherogenic, antiinflammatory and antidiabetic properties and these effects have been linked to its effect on high density lipoprotein cholesterol (HDL-c). Single nucleotide polymorphisms (SNPs) in the adiponectin gene influence adiponectin levels. We examined the relationship between HMW-adiponectin levels and cardiometabolic traits in normo- and hyperglycemic mixed ancestry South Africans and correlated these levels to two common polymorphisms.

Methods

HMW-adiponectin was determined in 101 subjects from the Cape Town Bellville South community-based study on a mixed ancestry population. Comparisons were made between individuals with normo- and hyperglycemia. Two common SNPs, ADIPOQ SNPs rs17300539 and rs266729, known to affect adiponectin levels were also tested for. Levels of HMW-adiponectin were then correlated with cardiometabolic traits in all groups.

Results

Levels of HMW-adiponectin were not significantly different in the normo- and hyperglycemic groups (median 11.6 vs. 10.5 μg/mL, p=0.3060) and in men and women (8.44 vs. 11.34 μg/mL, p=0.67). ADIPOQ SNPs rs17300539 and rs266729 did not influence levels of HMW-adiponectin. Robust correlation analyses revealed a significant positive correlation between HMW-adiponectin and HDL-c (r=0.45; 95%CI: 0.27–0.59), similarly in normo- and hyperglycemic participants (p > 0.99). This association was substantially attenuated in robust linear regressions adjusted for age, gender and adiposity.

Conclusions

Adiponectin levels in this population were not determined by the commonest SNPs of the adiponectin gene, were unaffected by glycemic status; but were significantly correlated with HDL-c levels. Previous studies have attributed some of the beneficial effects of adiponectin to its effect on HDL-c.