Association of KALRN, ADIPOQ, and FTO gene polymorphism in type 2 diabetic patients with coronary artery disease: possible predisposing markers

Minor alleles of FTO rs9939609 and rs17817449 polymorphisms confer a higher risk of type 2 diabetes mellitus and dyslipidemia, but not coronary artery disease in a Chinese Han population

Background

Relationships of the polymorphisms in fat mass and obesity-associated gene (FTO) and peroxisome proliferator-activated receptor delta gene (PPARD) with metabolic-related diseases remain to be clarified.

Methods

One thousand three hundred and eighty-one subjects were enrolled. Metabolic-related diseases including obesity, dyslipidemia, hyperhomocysteinemia, hyperuricemia, hypertension, type 2 diabetes mellitus (T2DM) and coronary artery disease (CAD) were defined based on diagnostic criteria. FTO rs9939609 and rs17817449, and PPARD rs2016520 and rs2267668 polymorphisms were genotyped by using polymerase chain reaction-restricted fragment length polymorphism method.

Results

Patients with T2DM or dyslipidemia had a higher frequency of AA, AT or AA + AT genotypes as well as A allele of FTO rs9939609 polymorphism than those free of T2DM or dyslipidemia (P ≤ 0.04 for all). Patients with T2DM or dyslipidemia had a higher frequency of GG, GT or GG + GT genotypes as well as G allele of FTO rs17817449 polymorphism than those free of T2DM or dyslipidemia (P ≤ 0.03 for all). Multivariate logistic regression analyses showed that FTO rs9939609 and rs17817449 polymorphisms were independently associated with T2DM as well as dyslipidemia after adjustment for age, sex, smoking and other metabolic diseases. FTO rs9939609 and rs17817449 polymorphisms were not associated with obesity, hyperhomocysteinemia, hyperuricemia, hypertension and CAD. Obese or T2DM carriers of the AA or AT genotype of the FTO rs9939609 polymorphism had a higher prevalence of dyslipidemia compared to non-obese or non-T2DM carriers of the AA or AT genotype (P = 0.03 for both). Among the carriers of GG or GT genotype of the FTO rs17817449 polymorphism, the prevalence of dyslipidemia in obese patients was higher than that in non-obese subjects (P < 0.01). PPARD rs2016520 and rs2267668 polymorphisms were not correlated with any of the metabolic-related diseases in the study population.

Conclusion

Minor alleles of FTO rs9939609 and rs17817449 polymorphisms confer a higher risk of T2DM and dyslipidemia, and the risk is further increased among obese individuals. PPARD rs2016520 and rs2267668 polymorphisms are not associated with metabolic-related diseases.

Type 2 diabetes linked FTO gene variant rs8050136 is significantly associated with gravidity in gestational diabetes in a sample of Bangladeshi women: Meta-analysis and case-control study

OBJECTIVE

Gestational diabetes mellitus (GDM) is a growing public health concern that has not been extensively studied. Numerous studies have indicated that a variant (rs8050136) of the fat mass-associated gene, FTO, is associated with both GDM and Type 2 diabetes mellitus(T2DM). We conducted a meta-analysis on the association between the FTO single nucleotide polymorphism (SNP) rs8050136 and T2DM, followed by a case-control study on the association of the said SNP and GDM in a sample of Bangladeshi women.

METHOD

A total of 25 studies were selected after exploring various databases and search engines, which were assessed using the Newcastle-Ottawa Scale (NOS). The MetaGenyo web tool was used to conduct this meta-analysis. A case-control study was performed on 218 GDM patients and 284 controls to observe any association between FTO rs8050136 and GDM. Genotyping was performed using the tetra-primer amplification refractory mutation system-polymerase chain reaction (T-ARMS) method, and statistical analyses were performed using various statistical softwares.

RESULTS

In the meta-analysis 26231 cases and 43839 controls were examined. Pooled association analyses revealed a statistically significant relationship between the FTO rs8050136 polymorphism and an elevated risk of T2DM under all genetic models (P<0.05). In the case-control study, synergistic analyses of the SNP and gravida with GDM revealed a significant (P<0.01) association with an increase in odds by 1.6 to 2.4 folds in multigravida and decrease in odds by 2 folds in primigravida. A positive family history of diabetes and the minor allele of this SNP collectively increased the risk of developing GDM by many-fold (1.8 to 2.7 folds). However, after accounting for family history of diabetes and gravidity, analyses showed no significant association with GDM.

CONCLUSION

Our meta-analysis revealed a significant association between SNP rs8050136 of FTO with T2DM, and this variant was substantially associated with an increased risk of GDM in a sample of Bangladeshi multigravida women.

Association of fat mass and obesity-associated (FTO) gene polymorphisms with non-communicable diseases (NCDs) in the Iranian population: A systematic review of observational studies

Background

Single nucleotide polymorphisms have been implicated in various diseases, most notably non-communicable diseases (NCDs). The aim of this study was to review available evidence regarding associations between FTO polymorphisms and NCDs in the Iranian population.

Methods

A comprehensive search was conducted through PubMed/Medline and Scopus databases up to December 2021, as well as reference lists of pertinent articles and key journals. All observational studies that examined the association between FTO gene polymorphisms and NCDs in the Iranian population were included. There was no limitation on the publication year. The Newcastle-Ottawa Scale (NOS) was used to assess the study's quality.

Results

The initial search yielded 95 studies, of which 30 studies were included in the current systematic review. The underlying disorders were obesity, type 2 diabetes, breast and colorectal cancers, depression, and metabolic syndrome. These studies found an association between FTO gene polymorphisms and obesity in the Iranian population, but the relationship with other NCDs was debatable. Even though, other diseases such as diabetes and metabolic syndrome, which are closely related to obesity, may also be associated with FTO gene polymorphisms.

Conclusion

FTO gene polymorphism appears to play a role in the occurrence of NCDs. Some of the study results may be misleading due to ethnic differences and the effect of other genetic factors on disease onset, which needs to be investigated further. Finally, FTO gene polymorphisms can be studied as a preventive or therapeutic target.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-022-01139-4.

Smooth muscle cell FTO regulates contractile function

The fat mass and obesity gene (FTO) is a N6-methyladenosine RNA demethylase that was initially linked by Genome-wide association studies to increased rates of obesity. Subsequent studies have revealed multiple mass-independent effects of the gene, including cardiac myocyte contractility. We created a mouse with a conditional and inducible smooth muscle cell deletion of Fto (Myh11 Cre+ Ftofl/fl) and did not observe any changes in mouse body mass or mitochondrial metabolism. However, the mice had significantly decreased blood pressure (hypotensive), despite increased heart rate and sodium, and significantly increased plasma renin. Remarkably, the third-order mesenteric arteries from these mice had almost no myogenic tone or capacity to constrict to smooth muscle depolarization or phenylephrine. Microarray analysis from Fto-/--isolated smooth muscle cells demonstrated a significant decrease in serum response factor (Srf) and the downstream effectors Acta2, Myocd, and Tagln; this was confirmed in cultured human coronary arteries with FTO siRNA. We conclude Fto is an important component to the contractility of smooth muscle cells.NEW & NOTEWORTHY We show a key role for the fat mass obesity (FTO) gene in regulating smooth muscle contractility, possibly by methylation of serum response factor (Srf).

Coronary Heart Disease in Type 2 Diabetes Mellitus: Genetic Factors and Their Mechanisms, Gene-Gene, and Gene-Environment Interactions in the Asian Populations

Asians are more susceptible to type 2 diabetes mellitus (T2D) and its coronary heart disease (CHD) complications than the Western populations, possibly due to genetic factors, higher degrees of obesity, insulin resistance, and endothelial dysfunction that could occur even in healthy individuals. The genetic factors and their mechanisms, along with gene-gene and gene-environment interactions associated with CHD in T2D Asians, are yet to be explored. Therefore, the objectives of this paper were to review the current evidence of genetic factors for CHD, summarize the proposed mechanisms of these genes and how they may associate with CHD risk, and review the gene-gene and gene-environment interactions in T2D Asians with CHD. The genetic factors can be grouped according to their involvement in the energy and lipoprotein metabolism, vascular and endothelial pathology, antioxidation, cell cycle regulation, DNA damage repair, hormonal regulation of glucose metabolism, as well as cytoskeletal function and intracellular transport. Meanwhile, interactions between single nucleotide polymorphisms (SNPs) from different genes, SNPs within a single gene, and genetic interaction with environmental factors including obesity, smoking habit, and hyperlipidemia could modify the gene's effect on the disease risk. Collectively, these factors illustrate the complexities of CHD in T2D, specifically among Asians.

Protective and therapeutic effects of two novel strains of Lactobacilli on diabetes-associated disorders induced by a high level of fructose

Diabetes is a metabolic disorder described as insufficient secretion of insulin in the pancreas or the inability of the existing insulin to function properly. It poses a greater risk on human health as it is considered the base of several diseases. Thus, this study was designed to evaluate two novel strains of Lactobacillus in handling pancreas disorders. 50 BALB/c male mice were divided into five groups; (a) feeding on normal diet only as control group, (b) given 21% fructose in drinking water as diabetes group, (c) feeding on Lactobacillus rhamnosus strain Pro2 (MT505335.1) plus 21% fructose as LR group, (d) feeding on Lactobacillus plantarum strain Pro1 (MT505334.1) plus 21% fructose as LP group and (e) mixture of two strains plus 21% fructose as Mix group. The serum content of glucose, aspartate aminotransferase (AST), and alanine aminotransferase (ALT) was determined. Pancreases histopathology was examined. Expression of GH, IGF1, and GLP-1 genes was measured in the liver and pancreas by RT-qPCR. Serum content of glucose, ALT, and AST significantly increased in diabetes group, and significantly reduced in (LP) and (Mix) groups compared with control. Pathological changes occurred in the exocrine and endocrine components of the diabetes group pancreas. Besides, islet cells are almost entirely disturbed and acinar cells degenerated. However, in (LP) and (Mix) groups, the pathological changes significantly decreased and became related to the control group. Expression of GH, IGF1, and GLP-1 genes was significantly downregulated in the liver and pancreas of mice given fructose compared with control. Expression of these genes was either significantly upregulated in groups (LP and Mix) or identical to the control group. This study shows that the strain Pro1 (MT505334.1) or a combination of two strains is useful in reducing diabetic risk.

RNA Modification by m6A Methylation in Cardiovascular Disease

Cardiovascular disease is currently the leading cause of death worldwide, and its underlying regulatory mechanisms remain largely unknown. N⁶-Methyladenosine (m⁶A) RNA methylation is an epigenetic modification involved in the splicing, nuclear export, translational regulation, and degradation of RNA. After the initial identification of m⁶A RNA methylation in 1974, the rise of next-generation sequencing technology to detect m⁶A throughout the transcriptome led to its renewed recognition in 2012. Since that time, m⁶A methylation has been extensively studied, and its functions, mechanisms, and effectors (e.g., METTL3, FTO, METTL14, WTAP, ALKBH5, and YTHDFs) in various diseases, including cardiovascular diseases, have rapidly been investigated. In this review, we first examine and summarize the molecular and cellular functions of m⁶A methylation and its readers, writers, and erasers in the cardiovascular system. Finally, we discuss future directions for m⁶A methylation research and the potential for therapeutic targeting of m⁶A modification in cardiovascular disease.

KALRN: A central regulator of synaptic function and synaptopathies

The synaptic regulator, kalirin, plays a key role in synaptic plasticity and formation of dendritic arbors and spines. Dysregulation of the KALRN gene has been linked to various neurological disorders, including autism spectrum disorder, Alzheimer's disease, schizophrenia, addiction and intellectual disabilities. Both genetic and molecular studies highlight the importance of normal KALRN expression for healthy neurodevelopment and function. This review aims to give an in-depth analysis of the structure and molecular mechanisms of kalirin function, particularly within the brain. These data are correlated to genetic evidence of patient mutations within KALRN and animal models of Kalrn that together give insight into the manner in which this gene may be involved in neurodevelopment and the etiology of disease. The emerging links to human disease from post-mortem, genome wide association (GWAS) and exome sequencing studies are examined to highlight the disease relevance of kalirin, particularly in neurodevelopmental diseases. Finally, we will discuss efforts to pharmacologically regulate kalirin protein activity and the implications of such endeavors for the treatment of human disease. As multiple disease states arise from deregulated synapse formation and altered KALRN expression and function, therapeutics may be developed to provide control over KALRN activity and thus synapse dysregulation. As such, a detailed understanding of how kalirin regulates neuronal development, and the manner in which kalirin dysfunction promotes neurological disease, may support KALRN as a valuable therapeutic avenue for future pharmacological intervention.

Integrate Molecular Phenome and Polygenic Interaction to Detect the Genetic Risk of Ischemic Stroke

Ischemic stroke (IS) is one of the leading causes of death, and the genetic risk of which are continuously calculated and detected by association study of single nucleotide polymorphism (SNP) and the phenotype relations. However, the systematic assessment of IS risk still needs the accumulation of molecular phenotype and function from the level of omics. In this study, we integrated IS phenome, polygenic interaction gene expression and molecular function to screen the risk gene and molecular function. Then, we performed a case-control study including 507 cases and 503 controls to verify the genetic associated relationship among the candidate functional genes and the IS phenotype in a northern Chinese Han population. Mediation analysis revealed that the blood pressure, high density lipoprotein (HDL) and glucose mediated the potential effect of SOCS1, CD137, ALOX5AP, RNLS, and KALRN in IS, both for the functional analysis and genetic association. And the SNP-SNP interactions analysis by multifactor dimensionality reduction (MDR) approach also presented a combination effect of IS risk. The further interaction network and gene ontology (GO) enrichment analysis suggested that CD137 and KALRN functioning in inflammatory could play an expanded role during the pathogenesis and progression of IS. The present study opens a new avenue to evaluate the underlying mechanisms and biomarkers of IS through integrating multiple omics information.

Lack of associations between the FTO polymorphisms and gestational diabetes: A meta-analysis and trial sequential analysis

BACKGROUND

Molecular epidemiological studies have sought associations between Fat mass and obesity associated (FTO) gene polymorphisms and gestational diabetes mellitus (GDM) risk, but findings are inconsistent. Hence, we performed a meta-analysis to clarify this problem.

METHODS

Case-control studies reporting the relationship of three FTO polymorphisms (rs9939609, rs8050136, and rs1421085) and GDM published before June 2018 were searched in 6 electronic databases such as PubMed and Embase. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of associations. Trial sequential analysis (TSA) was performed to evaluate the type 1 and type 2 errors.

RESULTS

A total of 5 studies involving 703 GDM cases and 2700 controls for rs9939609, 3 studies involving 1144 GDM cases and 909 controls for rs8050136, and 2 studies involving 207 GDM cases and 205 controls for rs1421085, were included in the meta-analysis. No association was observed between the three polymorphisms with the GDM risk under all genetic models. For example, the ORs and its 95% CIs under dominant genetic model were 0.88 (0.59, 1.33) for rs9939609, 1.11 (0.91, 1.35) for rs8050136, and 0.91 (0.58, 1.41) for rs1421085, respectively. Under TSA, there are insufficient levels of evidence for all of these three polymorphisms.

CONCLUSION

The present meta-analysis provides statistical evidence indicating a lack of association between FTO polymorphismsand GDM risk. More studies with larger sample size are needed to confirm these null associations.

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.

Association between FTO gene polymorphisms and type 2 diabetes mellitus, serum levels of apelin and androgen hormones among Iranian obese women

BACKGROUND AND AIMS

Recent studies show that FTO single nucleotide polymorphisms (SNPs) are associated with obesity and type 2 diabetes mellitus (T2DM). On the other hand, many animal models and clinical studies have demonstrated that apelin, an adipocytokine, is related to the obesity and T2DM. Additionally, obese women are at risk of Hyperandrogenemia. So, the aim of this study was to investigate the relationship between FTO variants (rs763967273, rs759031579, rs141115189, rs9926289, rs76804286 and rs9939609) with T2DM, serum apelin and androgenic hormones in Iranian obese women.

SUBJECTS AND METHODS

197 obese women (123 women with T2DM and 74 women as healthy control) were participated in this study. Anthropometrical and biochemical characteristics were measured. Serum apelin and androgen hormones levels were determined in 66 subjects consisting of 33 cases and 33 controls. PCR were carried out and subsequently, the PCR production was genotyped by Sanger sequencing assay.

RESULTS

Our observations showed that all SNPs are related to T2DM. The rs9926289 FTO variant had a strong association with serum apelin and dehydroepiandrosterone-sulfate levels (P=0.04 and P=0.03, respectively) among SNPs. In addition, apelin and androgenic hormones were correlated with T2DM. Two polymorphisms including rs9939609 and rs9926289 had a strong Linkage disequilibrium (r²=1).

CONCLUSION

FTO variants not only were associated with T2DM, but also some variants had a strong association with apelin and androgenic hormones profile.

Association of AdipoQ single-nucleotide polymorphisms and smoking interaction with the risk of coronary heart disease in Chinese Han population

AIMS

To investigate the impact of AdipoQ polymorphisms, and their additional interactions with smoking and drinking on coronary heart disease (CHD) risk based on Chinese population.

METHODS

Hardy‒Weinberg equilibrium (HWE) was performed using SNPStats (available online at http://bioinfo.iconcologia.net/SNPstats ). Generalized multifactor dimensionality reduction (GMDR) model was used to screen the best gene‒gene and gene‒environment interaction combinations. Logistic regression was performed to investigate association between four single-nucleotide polymorphisms (SNPs) and CHD and the interaction effect between rs1501299 and smoking.

RESULTS

Logistic analysis showed that CHD risks were higher in carriers with homozygous mutant of rs1501299 and rs2241766 than those with wild-type homozygotes, odds ratio (ORs) (95%CI) were 1.49 (1.19-1.95) and 1.71 (1.33-2.24), respectively, but CHD risks were lower in carriers with homozygous mutant of rs7649121 than those with wild-type homozygotes, OR (95%CI) was 0.72 (0.51-0.96). GMDR model indicated that there was a significant two-locus model (p = 0.0107) involving rs1501299 and current smoking, indicating a potential gene-environment interaction between rs1501299 and current smoking. Overall, the cross-validation consistency of this model was 9/10, and the testing accuracy was 60.11% (p = 0.0010). T-allele carriage had 42% prevalence, and one-quarter of them were current smokers. Smokers with rs1501299-GT or TT genotype have the highest CHD risk, compared to never-smokers with rs1501299-GG genotype, OR (95%CI) was 3.56 (1.91-5.42), after adjustment for gender, age, alcohol status, and body mass index. But we did not find any significant gene-gene and gene-drinking interaction combinations in GMDR models.

CONCLUSIONS

Polymorphisms in rs1501299 and rs2241766, and their additional interactions between rs1501299 and smoking were associated with increased CHD risks: polymorphism in rs7649121 was associated with decreased CHD risks.

Associations between two common single nucleotide polymorphisms (rs2241766 and rs1501299) of ADIPOQ gene and coronary artery disease in type 2 diabetic patients: a systematic review and meta-analysis

ADIPOQ gene polymorphisms were indicated to be associated with coronary artery disease (CAD) in diabetic patients, however, published studies reported inconsistent results. We performed this meta-analysis to reach a more accurate estimation of the relationship between two common ADIPOQ genetic polymorphisms (rs2241766 and rs1501299) and CAD risk in diabetic patients. Eligible studies were retrieved by searching PubMed, Embase, Wangfang, VIP database and China National Knowledge Infrastructure databases. Included and excluded criteria were formulated. The case group was diabetic patients with CAD, and the control group was diabetic subjects without CAD. Summary odds rations (ORs) and 95% confidence intervals (CIs) were used to evaluate ADIPOQ polymorphisms associations with CAD risk in diabetic group. Heterogeneity was evaluated by Q statistic and I² statistic. A total of twelve published articles, involving 3996 cases and 8876 controls were included in this meta-analysis. The pooled results from rs1501299 polymorphism showed decreased risk in homozygote model (TT VS GG: OR=0.67, 95%CI=0.54-0.83). Heterogeneity was detected in our study. Sensitivity analysis and subgroup analysis were conducted in the meta-analysis. For rs2241766 polymorphism, an increased risk was detected in Caucasian subgroup in heterozygote model (CT VS TT: OR=1.19, 95%CI=1.00-1.42). In genotyping method (PCR-RFLP) subgroup, an increased risk was found in recessive model (GG VS GT+TT: OR=2.05, 95%CI=1.23-3.39). In the sensitivity analysis of rs1501299, decreased risk was detected in allelic model (T VS G: OR=0.86, 95%CI=0.76-0.98) and recessive model (TT VS TG+GG: OR=0.47, 95%CI=0.33-0.67). Publication bias is not observed in our results. Our meta-analysis suggests that the rs1501299 polymorphism may play a protective role in CAD in diabetic patients. The rs2241766 polymorphism is found to be associated with a significant increase in CAD risk in Caucasian and genotyping method (PCR-RFLP) subgroups. Further studies are needed to confirm the prediagnostic effect of the two gene polymorphisms in CAD risk in diabetic patients.