Examining the effects of coronary artery disease- and mitochondrial biogenesis-related genes' and microRNAs' expression levels on metabolic disorders in epicardial adipose tissue

BACKGROUND AND AIMS

Epicardial adipose tissue (EAT) surrounds the heart and coronary arteries and is important for comprehending the pathogenesis of coronary artery disease (CAD). We aimed to evaluate the expressions of mitochondrial biogenesis- and CAD-related genes and miRNAs in EAT by comparing them to visceral adipose tissue (VAT) in CAD, diabetes, and obesity subgroups.

METHODS

In this study, a total of 93 individuals were recruited, and EAT samples (63 CAD; 30 non-CAD) and VAT samples from 65 individuals (46 CAD; 19 non-CAD) were collected. For further analysis, the study population was divided according to obesity and diabetes status. PRKAA1, PPARGC1A, SIRT1, RELA, TNFA, and miR-155-5p, let-7g-5p, miR-1247-5p, miR-326 expression levels were examined.

RESULTS

PRKAA1 and let-7g-5p were differentially expressed in EAT compared to VAT. TNFA expression was upregulated significantly in both tissues of CAD patients. In EAT, PRKAA1, PPARGC1A, and SIRT1 were downregulated with diabetes. Moreover, PPARGC1A expression is decreased under the condition of obesity in both tissues. EAT expressions of miR-1247-5p and miR-326 were downregulated with obesity, while miR-155-5p is decreased only in the VAT of obese. Also, miRNAs and genes were correlated with biochemical parameters and each other in EAT and VAT (p < 0.050).

CONCLUSIONS

The findings demonstrating distinct let-7g-5p and AMPKα1 mRNA expression between EAT and VAT underscores the importance of tissue-specific regulation in different clinical outcomes. In addition, the differential expressions of investigated genes and miRNAs highlight their responsiveness to obesity, DM, and CAD in adipose tissues.

Association of Intelectin 1 Gene rs2274907 A > T Polymorphism with Obesity, Type 2 Diabetes, Serum Intelectin-1 Levels and Lipid Profiles in Turkish Adults

The anti-inflammatory adipokine intelectin-1, which is encoded by the ITLN1 gene, is hypothesized to be linked to the pathogenesis of type 2 diabetes (T2DM) and obesity. The purpose of this study was to examine the effect of the ITLN1 gene polymorphism rs2274907 on obesity and T2DM in Turkish adults. The impact of genotype on lipid profiles and serum intelectin levels in the obese and diabetes groups was also investigated. Randomly selected 2266 adults (mean age, 55.0 ± 11.7 years; 51.2% women) participating in the population-based Turkish adult risk factor study were cross-sectionally analyzed. The genotyping of rs2274907 A > T polymorphism was performed by using the hybridization probe based LightSNiP assay in real-time PCR. T2DM were defined using the criteria of the American Diabetes Association. Obesity was described as Body mass index ≥ 30 kg/m2. Statistical analyses were used to investigate the association of genotypes with clinical and biochemical measurements. According to findings, there was no vital connection between the rs2274907 polymorphism and obesity, T2DM, or serum intelectin-1 level. The TA+AA carriers had significantly higher triglyceride levels (p = 0.007) compared with the TT carriers in both obese and T2DM women when adjusted for relevant covariates. ITLN1 rs2274907 polymorphism is not correlated with the risk of obesity and T2DM and not affect serum ITLN1 levels in Turkish adults. However, this polymorphism appears to be important in regulating triglyceride levels in obese and diabetic women.

Levels of miR-130b-5p in peripheral blood are associated with severity of coronary artery disease

BACKGROUND

Although patients with coronary artery disease (CAD) have a high mortality rate, the pathogenesis of CAD is still poorly understood. During the past decade, microRNAs (miRNAs) have emerged as new, potential diagnostic biomarkers in several diseases, including CAD. This study aimed to investigate the expression profiles of miRNAs in individuals with CAD and non-CAD.

METHODS AND RESULTS

The Agilent's microarray analyses were performed to compare the whole blood miRNA profile of selected individuals with severe CAD (n = 12, ≥ 90% stenosis) and non-CAD (n = 12, ≤ 20 stenosis). Expressions of selected differentially expressed miRNAs (DEMs) were analyzed for validation in individuals with critical CAD (n = 50) and non-CAD (n = 43) using real-time PCR. Target prediction tools were utilized to identify miRNA target genes. We identified 6 DEMs that were downregulated in CAD patients, which included hsa-miR-18a-3p and hsa-miR-130b-5p, that were analyzed for further testing. Expression levels of hsa-miR-130b-5p were found negatively correlated with SYNTAX score and stenosis in female CAD patients (p < 0.05). In addition, both miRNAs were found positively correlated with plasma HDL and inversely correlated with fasting triglyceride levels (p < 0.05). In linear regression analysis adjusted for several confounders, the correlations have remained statistically significant. Computational prediction of target genes indicated a relevant role of hsa-miR-130b-5p and hsa-miR-18a-3p in modulating the expression of genes associated with cardiovascular diseases.

CONCLUSION

Our findings highlight a significantly different pattern of miRNA expression in CAD patients in microarray results. Hsa-miR-18a-3p and hsa-miR-130b-5p might serve as biomarkers of CAD development and progression and warrant further attention.

The rs2175898 Polymorphism in the ESR1 Gene has a Significant Sex-Specific Effect on Obesity

Polymorphisms in the ESR1 gene have been associated with obesity and lipid metabolism. There are also important sex-related differences in the prevalence of obesity and related phenotypes. Therefore, we aimed to interrogate the association of the ESR1 rs2175898 gene polymorphism with obesity, obesity-related variables, and lipid levels in men and women as separate groups. Two thousand twenty-two randomly selected middle-aged and elderly Turks were genotyped for ESR1 rs2175898 polymorphism using real-time polymerase chain reaction with hybridization probes. We found sex-related differences of the ESR1 rs2175898 polymorphism in obesity. Logistic regression analysis after adjustment for age, smoking status, physical activity, diabetes mellitus, and the presence of menopause status in women demonstrated significantly decreased risk for obesity in female AG genotype carriers (OR 0.69; 95% CI 0.52-0.91; p = 0.010), and in male GG genotype carriers (OR 0.49; 95% CI 0.25-0.96; p = 0.039), Furthermore, carriers of the rs2175898 G allele exhibited a lower body mass index in both sexes and decreased waist circumference in women but not in men. Our findings also showed significantly higher serum total-C levels (p = 0.007) in the carriers of the AG+GG/AG genotype compared with the AA genotype in men. The AG genotype of the ESR1 rs2175898 polymorphism in women and GG genotype in men were found to have a decreased likelihood for obesity compared with the other rs2175898 genotypes.

Gender-specific associations of the APOA1 -75G>A polymorphism with several metabolic syndrome components in Turkish adults

BACKGROUND

Variations in the apolipoprotein A-1 (APOA1) gene, a determinant of plasma high-density lipoprotein cholesterol (HDL-C) and apoA-I levels, may contribute to cardiovascular diseases. We evaluated the effects of a promoter polymorphism (-75G>A) in the APOA1 gene on metabolic syndrome (MetS) components in a Turkish population sample.

METHODS

Randomly selected 1515 Turkish adults (age 49.9±11.8 years, 785 females) were genotyped for -75G>A polymorphism using hybridization probes in Real-Time PCR LC480 device. MetS and atherogenic dyslipidemia were defined using the criteria of ATP III.

RESULTS

The -75AA genotype prevailed in 3.9% of men and 2.4% of women, and was independently associated with significantly higher HDL-C concentrations. Independent associations with the -75GA genotype existed only in men: higher diastolic and systolic blood pressure (BP) levels (p<0.05) were observed in male -75GA heterozygotes. Logistic regression revealed that the GA genotype confers elevated risk for atherogenic dyslipidemia (OR=1.57, 95% Cl 1.06-2.3) after adjustment for associated risk factors. Independent associations with atherogenic dyslipidemia or elevated BP did not emerge in women.

CONCLUSION

APOA1 -75G>A polymorphism is independently related to HDL-C concentrations. Independent associations of the -75GA genotype with elevated BP and atherogenic dyslipidemia were confined to men. These gender-modulated associations suggest novel gene-gender-environmental interactions.

Gender- and obesity-specific effect of apolipoprotein C3 gene (APOC3) -482C>T polymorphism on triglyceride concentration in Turkish adults

BACKGROUND

Apolipoprotein C3 (APOC3) gene polymorphisms are associated with cardiometabolic risk factors, varying in ethnicities. This study aimed to investigate such association between the APOC3 -482C>T polymorphism and cardiometabolic risk factors in the turkish adult risk factor (TARF) study cohort, stratifying by gender and obesity.

METHODS

Randomly selected 1548 individuals (757 male and 791 female, mean age 49.9±11.8 years) were genotyped for -482C>T polymorphism using hybridization probes in a Real-Time PCR LC480 device.

RESULTS

The -482TT genotype prevailed 9.9% in men and 11.5% in women. Association between 482C>T polymorphism and dyslipidemia (p=0.036, OR=1.42, 95%Cl=1.02-1.97) was found only in men. Analysis of variance showed that anthropometric and metabolic variables were not differently distributed in APOC3 -482C>T genotypes in the study population. In relation to dyslipidemia and obesity, the -482C>T polymorphism showed significant gender-by-genotype interactions (p<0.01). When the study population was stratified according to gender and obesity, homozygotes for the T allele were associated strongly with (by 45%) elevated fasting triglyceride concentrations in obese men (p=0.009) and homeostatic model assessment (HOMA) index in non-obese women (p=0.013). Furthermore, in the same subgroups, the associations of the fasting triglyceride concentrations and HOMA index with the TT genotype remained after adjustment for risk factors (p<0.05).

CONCLUSIONS

APOC3 -482TT genotype is independently associated with elevated fasting triglyceride concentrations in obese men. Presence of obesity seems to be required for this genotype to induce markedly elevated triglycerides. Furthermore, it is associated with the dyslipidemia in men, without requirement of obesity.