Analysis of the Potential Association of Drug-Metabolizing Enzymes CYP2C9*3 and CYP2C19*3 Gene Variations With Type 2 Diabetes: A Case-Control Study

Molecular Dynamics Simulation of Kir6.2 Variants Reveals Potential Association with Diabetes Mellitus

Diabetes mellitus (DM) represents a problem for the healthcare system worldwide. DM has very serious complications such as blindness, kidney failure, and cardiovascular disease. In addition to the very bad socioeconomic impacts, it influences patients and their families and communities. The global costs of DM and its complications are huge and expected to rise by the year 2030. DM is caused by genetic and environmental risk factors. Genetic testing will aid in early diagnosis and identification of susceptible individuals or populations using ATP-sensitive potassium (KATP) channels present in different tissues such as the pancreas, myocardium, myocytes, and nervous tissues. The channels respond to different concentrations of blood sugar, stimulation by hormones, or ischemic conditions. In pancreatic cells, they regulate the secretion of insulin and glucagon. Mutations in the KCNJ11 gene that encodes the Kir6.2 protein (a major constituent of KATP channels) were reported to be associated with Type 2 DM, neonatal diabetes mellitus (NDM), and maturity-onset diabetes of the young (MODY). Kir6.2 harbors binding sites for ATP and phosphatidylinositol 4,5-diphosphate (PIP2). The ATP inhibits the KATP channel, while the (PIP2) activates it. A Kir6.2 mutation at tyrosine330 (Y330) was demonstrated to reduce ATP inhibition and predisposes to NDM. In this study, we examined the effect of mutations on the Kir6.2 structure using bioinformatics tools and molecular dynamic simulations (SIFT, PolyPhen, SNAP2, PANTHER, PhD&SNP, SNP&Go, I-Mutant, MuPro, MutPred, ConSurf, HOPE, and GROMACS). Our results indicated that M199R, R201H, R206H, and Y330H mutations influence Kir6.2 structure and function and therefore may cause DM. We conclude that MD simulations are useful techniques to predict the effects of mutations on protein structure. In addition, the M199R, R201H, R206H, and Y330H variant in the Kir6.2 protein may be associated with DM. These results require further verification in protein-protein interactions, Kir6.2 function, and case-control studies.

Genetic variation of CYP2C9 gene and its correlation with cardiovascular disease risk factors

BACKGROUND

The major enzyme that is responsible for Sulfonylureas (SUs) metabolism is hepatic cytochrome P-450 2C9 (CYP2C9). It is encoded by the polymorphic gene CYP2C9, which has many allelic variants, among those the CYP2C9*2 and CYP2C9*3 are the most common and clinically significant allelic variations. People with diabetes mellitus type 2 (T2DM) are more likely to develop cardiovascular disease (CVD), and their risk of dying from it is more than two times higher than that of people without the condition. The purpose of this study was to evaluate the association of genetic variations in the CYP2C9 gene with cardiovascular risk factors by investigating CYP2C9*1, *2, *3, *5, *11, and *13 allelic variants.

METHODS AND RESULTS

A total of 226 participants were enrolled in the current case-control study. Allele-specific amplification- PCR (ASA-PCR) was used to determine the allele of different variations and the results were confirmed by sequencing. The findings of this study showed the presence of the CYP2C9*2 allele in the T2DM group does not differ from its percentage in the control group. Also, CYP2C9*3 allele frequencies identified by Hardy-Weinberg equilibrium (HWE) analysis law were not significant, p = 0.6593 and 0.5828 in T2DM and control groups. There is no statistically significant difference between the control and diabetes groups involving the distribution of CYP2C9 alleles and CYP2C9*5, *11, and *13 polymorphisms were absent in the Iraqi population. No carrier for the CYP2C9*3 homozygous state was found in both groups.

CONCLUSIONS

According to these results T2DM patients with the CYP2C9*2 and *3 variants have an increased risk of developing hypertension.

Potential Association of The Pathogenic Kruppel-like Factor 14 (KLF14) and Adiponectin (ADIPOQ) SNVs with Susceptibility to T2DM

AIM

To evaluate the associations of the pathogenic variants in Kruppel-like Factor 14 (KLF 14) and Adiponectin (ADIPOQ) with susceptibility to type 2 diabetes mellitus (T2DM).

BACKGROUND

Type 2 diabetes mellitus (T2DM) is a pandemic metabolic disease characterized by increased blood sugar and caused by resistance to insulin in peripheral tissues and damage to pancreatic beta cells. Kruppel-like Factor 14 (KLF-14) is proposed to be a regulator of metabolic diseases, such as diabetes mellitus (DM) and obesity. Adiponectin (ADIPOQ) is an adipocytokine produced by the adipocytes and other tissues and was reported to be involved in T2DM.

OBJECTIVES

To study the possible association of the KLF-14 rs972283 and ADIPOQ-rs266729 with the risk of T2DM in the Saudi population.

METHODS

We have evaluated the association of KLF-14 rs972283 C>T and ADIPOQ-rs266729 C>G SNV with the risk to T2D in the Saudi population using the Amplification Refractory Mutation System PCR (ARMS-PCR), and blood biochemistry analysis. For the KLF-14 rs972283 C>T SNV we included 115 cases and 116 healthy controls, and ADIPOQ-rs266729 C>G SNV, 103 cases and 104 healthy controls were included.

RESULTS

Results indicated that the KLF-14 rs972283 GA genotype and A allele were associated with T2D risk with OR=2.14, p-value= 0.014 and OR=1.99, p-value=0.0003, respectively. Results also ADIPOQ-rs266729 CG genotype and C allele were associated with an elevated T2D risk with an OR=2.53, p=0.003 and OR=1.66, p-value =0.012, respectively.

CONCLUSION

We conclude that SNVs in KLF-14 and ADIPOQ are potential loci for T2D risk. Future large-scale studies to verify these findings are recommended. These results need further verifications in protein functional and large-scale case control studies before being introduced for genetic testing.

In Silico Evaluation of the Potential Association of the Pathogenic Mutations of Alpha Synuclein Protein with Induction of Synucleinopathies

Alpha synuclein (α-Syn) is a neuronal protein encoded by the SNCA gene and is involved in the development of Parkinson's disease (PD). The objective of this study was to examine in silico the functional implications of non-synonymous single nucleotide polymorphisms (nsSNPs) in the SNCA gene. We used a range of computational algorithms such as sequence conservation, structural analysis, physicochemical properties, and machine learning. The sequence of the SNCA gene was analyzed, resulting in the mapping of 42,272 SNPs that are classified into different functional categories. A total of 177 nsSNPs were identified within the coding region; there were 20 variants that may influence the α-Syn protein structure and function. This identification was made by employing different analytical tools including SIFT, PolyPhen2, Mut-pred, SNAP2, PANTHER, PhD-SNP, SNP&Go, MUpro, Cosurf, I-Mut, and HOPE. Three mutations, V82A, K80E, and E46K, were selected for further examinations due to their spatial positioning within the α-Syn as determined by PyMol. Results indicated that these mutations may affect the stability and function of α-Syn. Then, a molecular dynamics simulation was conducted for the SNCA wildtype and the four mutant variants (p.A18G, p.V82A, p.K80E, and p.E46K). The simulation examined temperature, pressure, density, root-mean-square deviation (RMSD), root-mean-square fluctuation (RMSF), solvent-accessible surface area (SASA), and radius of gyration (Rg). The data indicate that the mutations p.V82A, p.K80E, and p.E46K reduce the stability and functionality of α-Syn. These findings highlight the importance of understanding the impact of nsSNPs on α-syn structure and function. Our results required verifications in further protein functional and case-control studies. After being verified these findings can be used in genetic testing for the early diagnosis of PD, the evaluation of the risk factors, and therapeutic approaches.

Comprehensive Molecular Evaluation of HNF-1 Alpha, miR-27a, and miR-146 Gene Variants and Their Link with Predisposition and Progression in Type 2 Diabetes Patients

BACKGROUND

Type 2 diabetes (T2D) is a metabolic condition induced by insulin resistance and pancreatic beta cell dysfunction. MicroRNAs (miRNAs) have biological significance because they regulate processes such as the molecular signaling pathways involved in the pathophysiology of diabetes mellitus. The hepatocyte nuclear factor-1 alpha (HNF-1 alpha) is a transcription factor found in hepatocytes and the pancreas. Mutations in the HNF-1 alpha gene were reportedly associated with maturity-onset diabetes of the young (MODY). The objective of the present study was to examine the associations between MiR-27a, MiR-146, and HNF-1 alpha single-nucleotide variations (SNVs) with T2D risk in the Saudi population.

METHODOLOGY

We evaluated the association of SNVs of miR-27a rs895819 A>G, 146a-rs2910164 C>G, and HNF-1 alpha rs1169288 G>T (I27L) with the risk of T2D in Saudi patients with the Amplification Refractory Mutation System PCR (ARMS-PCR). For the miR-27a SNVs, we used 115 cases (82 males, 33 females) and 117 matched healthy controls (HCs); for the Mir-146 SNVs, we used 103 cases (70 males, 33 females) and 108 matched HCs; and for the HNF-1 alpha, we employed 110 patients (80 males, 30 females) and 110 HCs. The blood biochemistry of the participants was essayed using commercial kits, and the methods of statistical analysis used were the Chi-square test, the Fisher exact test, and a multivariate analysis based on logistic regression, like the odds ratio (OD) and risk ratio (RR), with 95% confidence intervals (CIs).

RESULTS

The MiR-27a rs895819 AG genotype was linked to increased T2D susceptibility, with OR = 2.01 and p-value = 0.011, and the miR-146 rs2910164 CG genotype and C allele were linked to an elevated risk of T2D, with OR = 2.75, p-value < 0.0016, OR = 1.77, and p-value = 0.004. The results also showed that the GT genotype and T allele of the HNF-1 alpha (rs1169288) G>T is linked to T2D, with OR = 2.18, p-value = 0.0061, and 1.77, p-value = 0.0059.

CONCLUSIONS

The SNVs in miR-27a, miR-146, and HNF-1 alpha can be potential loci for T2D risk. The limitations of this study include the relatively small sample size and the fact that it was a cross-sectional study. To our knowledge, this is the first study to highlight the association between miR-27a, miR-146, and HNF-1 alpha SNVs and the risk of T2D in the Saudi population. Future large-scale case-control studies, as well as studies on the functions of the proteins and protein interaction studies for HNF-1 alpha, are required to verify our findings. Furthermore, these findings can be used for the identification and stratification of at-risk populations via genetic testing for T2D-prevention strategies.

Genetic Determinants of Cardiovascular Disease: The Endothelial Nitric Oxide Synthase 3 (eNOS3), Krüppel-Like Factor-14 (KLF-14), Methylenetetrahydrofolate Reductase (MTHFR), MiRNAs27a and Their Association with the Predisposition and Susceptibility to Coronary Artery Disease

Coronary artery disease (CAD) is an important cause of death worldwide. CAD is caused by genetic and other factors including hypertension, hyperlipidemia, obesity, stress, unhealthy diet, physical inactively, smoking and Type 2 diabetes (T2D). The genome wide association studies (GWASs) have revealed the association of many loci with risk to diseases such as cancers, T2D and CAD. Nitric oxide (NO) is a potent vasodilator and is required for normal vascular health. It is produced in the endothelial cells in a reaction catalyzed by the endothelial NO synthase (eNOS). Methylenetetrahydrofolate reductase (MTHFR) is a very important enzyme involved in metabolism of folate and homocysteine, and its reduced function leads to cardiovascular disease. The Krüppel-like factor-14 (KLF-14) is an important transcriptional regulator that has been implicated in metabolic syndrome. MicroRNA (MiRNAs) are short non-coding RNAs that regulate the gene expression of proteins involved in important physiological processes including cell cycle and metabolism. In the present study, we have investigated the potential impact of germline pathogenic variants of endothelial eNOS, KLF-14, MTHFR, MiRNA-27a and their association with risk to CAD in the Saudi population. Methods: Amplification Refractory Mutation System (ARMS) PCR was used to detect MTHFR, KLF-14, miRNA-27a and eNOS3 genotyping in CAD patients and healthy controls. About 125 CAD cases and 125 controls were enrolled in this study and statistical associations were calculated including p-value, risk ratio (RR), and odds ratio (OD). Results: There were statistically significant differences (p < 0.05) in genotype distributions of MTHFR 677 C>T, KLF-14 rs972283 G>A, miRNAs27a rs895819 A>G and eNOS3 rs1799983 G>T between CAD patients and controls. In addition, our results indicated that the MTHFR-TT genotype was associated with increased CAD susceptibility with an OR 2.75 (95%) and p < 0.049, and the KLF14-AA genotype was also associated with increased CAD susceptibility with an OR of 2.24 (95%) and p < 0.024. Moreover, the miRNAs27a-GG genotype protects from CAD risk with an OR = 0.31 (0.016), p = 0.016. Our results also indicated that eNOS3 -GT genotype is associated with CAD susceptibility with an OR = 2.65, and p < 0.0003. Conclusion: The MTHFR 677C>T, KLF14 rs972283 G>A, miRNAs27a A>G, and eNOS3 rs1799983 G>T genotypes were associated with CAD susceptibility (p < 0.05). These findings require verification in future large-scale population based studies before these loci are used for the prediction and identification of individuals at risk to CAD. Weight control, physical activity, and smoking cessation are very influential recommendations given by clinicians to the at risk individuals to reduce or delay the development of CAD.

Clinical Correlations of Lipid Profiles with the Age and Gender in the Coronary Artery Disease Patients: A Study of 3878 CAD Patients from India

BACKGROUND

Cardiovascular diseases (CVDs) are crucial cause of death and hospitalization all over the world including India. The CVDs including the coronary artery disease (CAD) are developed by the interaction of genetic and environmental factors. Hyperlipidemia is a traditional risk factor for CVD.

AIM

The aim of this study was to study the clinical correlations of lipid profiles with the age and gender in the Coronary Artery Disease Patients: Methods: In this study, we have investigated the effect of age and sex on in lipid profile in 3878 (1171 females and 2707 males) CAD patients from India.

RESULTS

The plasma TG was higher in males than in females regardless of the age. Results showed that CAD female patients had significantly increased HDL-C than their aged matched males. Moreover, the plasma TC and LDL-C were significantly higher in males than females until age 40 years. Then after the age of 40 years, TC and LDL-C become significantly higher in females than in males. In addition, we found that more than 85% of CAD cases were <55 years old, and about 30% of CAD cases had normal lipid profile.

CONCLUSION

We conclude that elderly females are at a greater risk for CAD than males. Moreover, there were no significant differences in CVDs causes between nonelderly and elderly females. In addition, a higher percentage of cases were premature CAD, and 30% of CAD may be caused by loci that are not related to lipid metabolism.

The Impact of the Coronavirus (COVID-19) Infection on the Drug-Metabolizing Enzymes Cytochrome P450s

Coronaviruses cause disease in human and animals. In 2019 a novel coronavirus was first characterized in Wuhan, China. It causes acute respiratory disease and designated the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or COVID-19. The COVID-19 spread to all cities of China, and in 2020 to the whole world. Patients with COVID-19 may recover without medical treatment. However, some patients need medical care. The Cytochrome p450s (CYP450s) are large superfamily of enzymes catalyze the metabolism of endogenous substrates and xenobiotics. CYP450s catalyze the biotransformation of 80% of the drug in clinical use. The CYP450 present in liver, lungs, intestine and other tissues. COVID-19 has been reported to decrease the activity of certain isoforms of CYP450s in an isoform specific manner. Furthermore, the COVID-19 infection decreases the liver functions including the drug clearance or detoxification medicated by the CYP450s. The healthcare providers should be aware of this disease-drug interaction when prescribing drugs for treatment of COVID-19 and other comorbidities.

Biological and clinical implications of TNF-α promoter and CYP1B1 gene variations in Coronary Artery Disease susceptibility

BACKGROUND

Cardiovascular diseases (CVD) are important causes of death worldwide. Atherosclerosis is a chronic inflammatory disorder. It is the major cause of CVD and is manifested by ischemic heart disease or coronary artery disease (CAD). TNF-α is a pro-inflammatory cytokine that regulates immune response and promotes the development of atherosclerosis. Cytochrome p450 1B1 (CYP1B1) is an enzyme involved in the metabolism of endogenous and exogenous substrates.

OBJECTIVES

This study aimed at examining the association of TNF-α rs1800629 G >A and CYP1B1 rs1056827 G>T gene polymorphisms with CAD susceptibility in an Indian cohort.

METHODS

AS-PCR and direct DNA sequencing were used to examine the association of TNF-α rs1800629 G >A and CYP1B1 rs1056827 G>T gene polymorphism with CAD in an Indian cohort. A total of 100 clinically confirmed cases of CAD and 110 matched apparently healthy controls were genotyped.

RESULTS

Allelic and genotypic frequencies did not deviate from Hardy-Weinberg equilibrium in the controls (p>0.05) for TNF-α G-308A and CYP1B1 rs1056827G>A. There was no significant difference between the TNF-α rs1800629 A>G genotype distribution between cases and controls (P-value >0.05). A significant difference was observed between the CYP1B1 rs1056827 G>T genotype distribution between CAD cases and controls (P<0.0003). Our result indicated that in the codominant model, the GA genotype of the CYP1B1 rs1056827 G>T was associated with CAD with OR= 2.21(1.17 to 4.15), RR=1.38(1.07 to 1.78), and P<0.013. In the dominant model, the (GA+AA) genotype was associated with CAD with OR=2.79(1.54 to 5.05) and P<0.007. The CYP1B1 rs1056827 'A' allele was associated with CAD with OR = 2.30 (1.55 to 3.42) and P< 0.0001. Our results indicated that TNF-α 1800629 gene polymorphism was strongly associated with hypercholesteremia (P<0.0009), HDL (P<0.0001), TGL (P<0.039), hypertension (P<0.0001), and smoking (P<0.0001) in patients with Coronary Artery Disease. Similar correlations of CYP1B1 rs1056827 genotypes were reported with cholesterol (P<0.020), HDL (P<0.002), LDL (P<0.006), hypertension (P<0.03), and smoking (P<0.005).

CONCLUSION

It was reported that the GA genotype of the CYP1B1 rs1056827 G>T was strongly associated with susceptibility to Coronary Artery Disease with OR= 2.21(1.17 to 4.15)) and P<0.013, and similarly, its A allele was associated with predisposition to CAD with OR = 2.30(1.55 to 3.42) and P< 0.0001. Our results indicated that TNF-α 1800629 gene polymorphism is not associated with predisposition to Coronary Artery Disease. Nevertheless, these results should be taken with caution and further validated with larger-scale studies before being introduced in the clinical setting.

Clinical Implications of MiR128, Angiotensin I Converting Enzyme and Vascular Endothelial Growth Factor Gene Abnormalities and Their Association with T2D

Type 2 DM (T2D) results from the interaction of the genetic and environmental risk factors. Vascular endothelial growth factor (VEGF), angiotensin I-converting enzyme (ACE), and MicroRNAs (MiRNAs) are involved in important physiological processes. Gene variations in VEGF, ACE and MiRNA genes are associated with diseases. In this study we investigated the associations of the VEGF-2578 C/A (rs699947), VEGF-2549 insertion/deletion (I/D), and ACE I/D rs4646994 and Mir128a (rs11888095) gene variations with T2D using the amplification refractory mutation system PCR (ARMS-PCR) and mutation specific PCR (MSP). We screened 122 T2D cases and 126 healthy controls (HCs) for the rs699947, and 133 T2D cases and 133 HCs for the VEGF I/D polymorphism. For the ACE I/D we screened 152 cases and 150 HCs, and we screened 129 cases and 112 HCs for the Mir128a (rs11888095). The results showed that the CA genotype of the VEGF rs699947 and D allele of the VEGF I/D polymorphisms were associated with T2D with OR =2.01, p-value = 0.011, and OR = 2.42, p-value = 0.010, respectively. The result indicated the D allele of the ACE ID was protective against T2D with OR = 0.10, p-value = 0.0001, whereas the TC genotype and the T allele of the Mir128a (rs11888095) were associated with increased risk to T2D with OR = 3.16, p-value = 0.0001, and OR = 1.68, p-value = 0.01, respectively. We conclude that the VEGF (rs699947), VEGF I/D and Mir128a (rs11888095) are potential risk loci for T2D, and that the D allele of the ACE ID polymorphism may be protective against T2D. These results help in identification and stratification for the individuals that at risk for T2D. However, future well-designed studies in different populations and with larger sample sizes are required. Moreover, studies to examine the effects of these polymorphisms on VEGF and ACE proteins are recommended.

Molecular Determination of mirRNA-126 rs4636297, Phosphoinositide-3-Kinase Regulatory Subunit 1-Gene Variability rs7713645, rs706713 (Tyr73Tyr), rs3730089 (Met326Ile) and Their Association with Susceptibility to T2D

Type 2 diabetes is a metabolic disease characterized by elevated blood sugar. It has serious complications and socioeconomic impact. The MicroRNAs are short single-stranded and non-coding RNA molecules. They regulate gene expression at the post-transcriptional levels. They are important for many physiological processes including metabolism, growth, and others. The phosphoinositide 3-kinase (PI3K) is important for insulin signaling and glucose uptake. The genome wide association studies have identified the association of certain loci with diseases including T2D. In this study we have examined the association of miR126 rs4636297 and Phosphoinositide-3-kinase regulatory subunit 1 (PIK3R1) gene Variations rs7713645, rs706713 (Tyr73Tyr), and rs3730089 (Met326Ile) with T2D using the amplification refractory mutation system PCR. Results indicated that there was a significant different (p-value < 0.05) in the Mir126 rs4636297 genotypes distribution between cases and controls, and the minor allele of the rs4636297 was also associated with T2D with OR = 0.58, p-value < 0.05. In addition results showed that there were significant differences (p-value < 0.05) of rs4636297 genotype distribution of patients with normal and patient with abnormal lipid profile. Results also showed that the PIK3R1 rs7713645 and rs3730089 genotype distribution was significantly different between cases and controls with a p-values < 0.05. In addition, the minor allele of the rs7713645 and rs3730089 were associated with T2D with OR = 0.58, p-value < 0.05. We conclude that the Mir126 rs4636297 and PIK3R1 SNPs (rs7713645 and rs3730089) were associated with T2D. These results need verification in future studies with larger sample sizes and in different populations. Protein-protein interaction and enzyme assay studies are also required to uncover the effect of the SNPs on the PI3K regulatory subunit (PI3KR1) and PI3K catalytic activity.

Role of Selected miRNAs as Diagnostic and Prognostic Biomarkers in Cardiovascular Diseases, Including Coronary Artery Disease, Myocardial Infarction and Atherosclerosis

Cardiovascular diseases are the leading cause of death worldwide in different cohorts. It is well known that miRNAs have a crucial role in regulating the development of cardiovascular physiology, thus impacting the pathophysiology of heart diseases. MiRNAs also have been reported to be associated with cardiac reactions, leading to myocardial infarction (MCI) and ultimately heart failure (HF). To prevent these heart diseases, proper and timely diagnosis of cardiac dysfunction is pivotal. Though there are many symptoms associated with an irregular heart condition and though there are some biomarkers available that may indicate heart disease, authentic, specific and sensitive markers are the need of the hour. In recent times, miRNAs have proven to be promising candidates in this regard. They are potent biomarkers as they can be easily detected in body fluids (blood, urine, etc.) due to their remarkable stability and presence in apoptotic bodies and exosomes. Existing studies suggest the role of miRNAs as valuable biomarkers. A single biomarker may be insufficient to diagnose coronary artery disease (CAD) or acute myocardial infarction (AMI); thus, a combination of different miRNAs may prove fruitful. Therefore, this review aims to highlight the role of circulating miRNA as diagnostic and prognostic biomarkers in cardiovascular diseases such as coronary artery disease (CAD), myocardial infarction (MI) and atherosclerosis.

Glutathione S-Transferase (GSTT1 rs17856199) and Nitric Oxide Synthase (NOS2 rs2297518) Genotype Combination as Potential Oxidative Stress-Related Molecular Markers for Type 2 Diabetes Mellitus

BACKGROUND

Deregulation of the antioxidant enzymes was implicated in pathogenesis and complications of type 2 diabetes mellitus (T2DM). The data relate the genetic variants of these enzymes to T2DM are inconsistent among various populations.

PURPOSE

We aimed to explore the association of 13 genetic variants of "superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST) and nitric oxide synthase (NOS)" with T2DM susceptibility and the available clinical laboratory data.

SUBJECTS AND METHODS

A total of 384 individuals were enrolled in this work. Different genotypes of the genes mentioned above were characterized using TaqMan OpenArray Genotyping assays on a Real-Time polymerase chain reaction system.

RESULTS

After age- and sex-adjustment, among the studied 13 variants, GSTT1 rs17856199 was associated with T2DM under homozygote (OR=3.42; 95% CI:1.04-11.2, p=0.031), and recessive (OR=3.57; 95% CI: 1.11-11.4, p=0.029) comparison models. The NOS2 rs2297518*A allele was more frequent among the T2DM cohort (58.1% vs 35.4%, p<0.001) and showed a dose-response effect; being heterozygote was associated with higher odds for developing DM (OR=4.06, 95% CI=2.13-7.73, p<0.001), whereas being AA homozygote had double the risk (OR=9.06, 95% CI=3.41-24.1, p<0.001). Combined NOS2 rs2297518*A and either GSTT1 rs17856199*A or *C genotype carriers were more likely to develop T2DM. Different associations with sex, BMI, hyperglycemia, and/or hyperlipidemia were evident. The principal component analysis revealed NOS2 rs2297518*G, old age, dyslipidemia, high systolic blood pressure, and elevated HbA1c were the main classifiers of T2DM patients.

CONCLUSION

The oxidative stress-related molecular markers, GSTT1 rs17856199 and NOS2 rs2297518 variants were significantly associated with T2DM risk and phenotype in the study population.