Association of PPAR-γ2 and β3-AR Polymorphisms With Postmenopausal Hypertension

The Influence of FAM13A and PPAR-γ2 Gene Polymorphisms on the Metabolic State of Postmenopausal Women

Recently, we have observed two significant pandemics caused by communicable (COVID-19) and non-communicable factors (obesity). Obesity is related to a specific genetic background and characterized by immunogenetic features, such as low-grade systemic inflammation. The specific genetic variants include the presence of polymorphism of the Peroxisome Proliferator-Activated Receptors gene (PPAR-γ2; Pro12Ala, rs1801282, and C1431T, rs3856806 polymorphisms), β-adrenergic receptor gene (3β-AR; Trp64Arg, rs4994), and Family With Sequence Similarity 13 Member A gene (FAM13A; rs1903003, rs7671167, rs2869967). This study aimed to analyze the genetic background, body fat distribution, and hypertension risk in obese metabolically healthy postmenopausal women (n = 229, including 105 lean and 124 obese subjects). Each patient underwent anthropometric and genetic evaluations. The study has shown that the highest value of BMI was associated with visceral fat distribution. The analysis of particular genotypes has revealed no differences between lean and obese women except for FAM13A rs1903003 (CC), which was more prevalent in lean patients. The co-existence of the PPAR-γ2 C1431C variant with other FAM13A gene polymorphisms [rs1903003(TT) or rs7671167(TT), or rs2869967(CC)] was related to higher BMI values and visceral fat distribution (WHR > 0.85). The co-association of FAM13A rs1903003 (CC) and 3β-AR Trp64Arg was associated with higher values of systolic (SBP) and diastolic blood pressure (DBP). We conclude that the co-existence of FAM13A variants with C1413C polymorphism of the PPAR-γ2 gene is responsible for body fat amount and distribution.

Gene variants and haplotypes of Vitamin D biosynthesis, transport, and function in preeclampsia

Objective: To find whether the gene variants and haplotypes of cytochrome (CYP) 27B1 (1α-hydroxylase), group-specific component (GC) that is a vitamin D binding protein, vitamin D receptor (VDR), peroxisome proliferator-activated receptor γ (PPARγ) and retinoid-X receptor (RXR) affect the risk of preeclampsia. Methods: In a case-control study 100 women with preeclampsia and 100 healthy pregnant women were investigated for gene variants and haplotypes of vitamin D biosynthesis, transport, and function using the polymerase chain reaction-restriction fragment length polymorphism method. Results: The frequency of gene variants of PPARγ Pro12Ala and RXR -α (A/G, rs749759) were not significantly different comparing patients and controls. The TT genotype of CYP 27B1 (G > T) was associated with 2.2-fold (95% CI 1.04-4.7, p = 0.039) increased risk of early-onset preeclampsia. Also, the TT genotype of GC rs7041 (T > G) increased the risk of preeclampsia [OR = 2.13 (95% CI 1.09-4.17, p = 0.027)]. The VDR ApaI GT genotype elevated susceptibility to preeclampsia (OR = 2.55, p = 0.04). Further, the presence of VDR ApaI GT+TT genotype was associated with higher levels of body mass index, and systolic blood pressure, and lower level of 25 (OH)-D3. In the presence of haplotype CYP T, VDR T, and RXR A (TTA) compared to haplotype GTG the risk of preeclampsia was 6.71-fold (p = 0.044). Conclusions: The present study indicated an association between the CYP 27B1, GC, and VDR ApaI variants with the risk of preeclampsia. Also, the variants of the latter polymorphism influenced BMI, blood pressure, and vitamin D levels.

Genetic Background of Hypertension in Connective Tissue Diseases

Peroxisome proliferator-activated receptors (PPAR gamma-2) and beta-3-adrenergic receptors (ADRB3) are involved in the risk of hypertension. But their exact role in blood pressure modulation in patients with connective tissue diseases (CTD) is still not well defined. In this study, 104 patients with CTD and 103 gender- and age-matched controls were genotyped for Pro12Ala and C1431T polymorphisms of the PPAR gamma-2 gene and Trp64Arg polymorphism of the ADRB gene. Anthropometric and biochemical measurements were evaluated, followed by genotyping using TaqMan® SNP genotyping assays and polymerase chain reaction-restriction fragment length polymorphism. The prevalence of analyzed genotypes and alleles was comparable between patients with CTD and the control group, as well as hypertensive and normotensive subjects. Patients with CTD have lower body fat and higher body water amount, serum glucose, and triglyceride (TG) levels. Hypertensive subjects are older and have higher body mass, BMI, waist circumference (WC), body water content, glucose, and TG concentration. The multivariate analysis revealed that hypertensive subjects with Ala12/X or Trp64Trp have higher body mass and WC when compared to normotensive subjects. Trp64Trp polymorphism was also characterized by a higher TG level, while T1431/X subjects had higher WC. The presence of CTD, visceral fat distribution, and increased age are the predictors of hypertension development. Hypertensive patients with CTD and Trp64Trp polymorphism have an increased risk of visceral obesity development and metabolic complications, which in turn affects the value of blood pressure. In addition, either Ala12/X or T1431/X predicts the visceral body fat distribution in hypertensive subjects.

Association between peroxisome proliferator-activated receptor γ-2 gene Pro12Ala polymorphisms and risk of hypertension: an updated meta-analysis

Previous studies investigate the relationship between peroxisome proliferator-activated receptor γ-2 (PPAR) gene Pro12Ala polymorphisms and risk of hypertension. However, the number of available studies was extremely limited. We updated this evidence and gave more significant results. We performed comprehensive computer-based searches in the PubMed, Web of Science, Embase, Google Scholar, the Cochrane library, Wanfang database, China National Knowledge Infrastructure, and China Biological Medicine Database. All studies that reported the association between the PPARγ2Pro12Ala polymorphisms and hypertension were identified. Twenty-one studies were finally included in the present study. In the domain model, the PPARγ1Pro12Ala polymorphism was not associated with hypertension (odds ratio (OR) = 0.85, 95% confidence interval (CI): 0.71-1.03, P=0.108). The significant relationship was found in the recessive model (OR = 0.67, 95% CI: 0.53-0.85), in the additive model (OR = 0.61, 95% CI: 0.48-0.77), and in the allele genetic model (OR = 0.81, 95% CI: 0.66-0.99). Subgroup analysis indicated that the PPARγ1Pro12Ala polymorphism from the all gene models was also not related to the risk of hypertension in Caucasians. In Asians, however, the results (P=0.002; I² = 57.6%) suggested a significant relationship between PPARγ1Pro12Ala and hypertension in the domain model (OR = 0.80, 95% CI: 0.65-0.99), in the recessive model (OR = 0.57, 95% CI: 0.44-0.75), in the additive model (OR = 0.51, 95% CI: 0.39-0.66), and in the allele model (OR = 0.75, 95% CI: 0.60-0.94). The PPARγ1Pro12Ala polymorphism could affect the risk of primary hypertension amongst Asians. The A allele gene was a protective genotype for primary hypertension. The PPARγ1Pro12Ala polymorphism was not associated with hypertension amongst Caucasians.

The mutation of Trp64Arg in β3-adrenoreceptor-encoding gene is significantly associated with increased hypertension risk and elevated blood pressure: a meta-analysis

This meta-analysis was implemented to test the association of a missense mutation, Trp64Arg, in β3-adrenoreceptor-encoding gene (ADRB3) with both hypertension risk and blood pressure (BP) changes. A systematic search of three publicly-available databases was launched to look for articles published as of December 2016. Qualification appraisal and data extraction were independently done by two researchers. Pooled estimates were expressed as odds ratio (OR) or weighted mean difference (WMD), and their 95% confidence intervals (95% CIs). There were separately 21 (3750/4225 patients/controls) and 17 (6100 subjects) individual studies for hypertension risk and BP changes. Integral analyses revealed that Trp64Arg mutation was associated with the significantly increased risk of hypertension, and particularly, the 64Trp/64Arg heterozygote carriers were 1.23-times more likely to develop hypertension compared with the 64Trp/64Trp homozygote carriers (OR = 1.23, 95% CI: 1.02∼1.46, P = 0.021). Publication bias was extremely low for all integral comparisons. In stratified analyses, significance was spotted in populations of Chinese descent, in retrospective studies, in hospital-based studies, in age-matched case-control studies, in studies enrolling patients with mean body mass index < 25 kg/m² and in studies with total sample size ≥ 240. Heterogeneity was improved for most stratified comparisons. Further in hypertensive patients, the 64Trp/64Arg heterozygote carriers had significantly higher systolic (WMD = 0.87 mmHg, 95% CI: 0.39∼1.35, P < 0.001) and diastolic (WMD = 0.88 mmHg, 95% CI: 0.59∼1.17, P < 0.001) BP than 64Trp/64Trp homozygote carriers. Altogether, ADRB3 gene Trp64Arg mutation was significantly associated with an increased predisposition toward hypertension and elevated systolic/diastolic BP in hypertensive patients, suggesting that Trp64Arg is an important hypertension-susceptibility marker.

Association between potassium channel SNPs and essential hypertension in Xinjiang Kazak Chinese patients

The aim of the present study was to examine whether single-nucleotide polymorphisms (SNPs) of β1 subunit of large-conductance Ca²⁺-activated K⁺ channel (KCNMB1) and inwardly rectifying K⁺ channel, subfamily J, member-11 (KCNJ11) are associated with essential hypertension (EH) in Xinjiang Kazak Chinese patients. A polymerase chain reaction-restriction fragment length polymorphism technique was applied to detect the distribution of selected alleles and genotype frequencies in a cohort of Xinjiang Kazak Chinese patients. Samples from 267 patients with EH and 259 normotensive (NT) controls were analyzed. An unconditional logistic regression analysis was used to estimate the odds ratio and 95% confidence interval of the risk factors that are associated with the development of EH. Genotype and allele frequency analyses revealed that the frequency of genotypes KCNJ11-rs2285676 and KCNMB1-rs11739136 was not significantly different between the EH and NT groups. Individuals carrying the GG genotype of KCNJ11-rs5219 had a 2.08 times higher risk of having EH than individuals carrying the GA+AA genotype of KCNJ11-rs5219. Furthermore, the G allele frequency of KCNJ11-rs5219 in the EH group was significantly higher than that of the NT group (P=0.048). Additionally, logistic regression analysis revealed that the body weight and GG genotype of KCNJ11-rs5219 were positively associated with EH in Xinjiang Kazak Chinese patients (P<0.01).

Associations between PPARG polymorphisms and the risk of essential hypertension

Background

Peroxisome proliferator-activated receptor gamma (PPARG) plays an important role in the pathogenesis and maintenance of essential hypertension (EH). It has been suggested that polymorphisms of PPARG are associated with the risk of EH. However, findings to date remain controversial. To elucidate the associations between the PPARG Pro12Ala and C161T polymorphisms and EH risk, a meta-analysis was carried out.

Methods

A comprehensive literature search of PubMed, Embase, CNKI (Chinese National Knowledge Infrastructure), VIP and Wanfang databases was conducted. The pooled odds ratios (ORs) and 95% confidence interval (CI) were calculated to estimate the size of the effect using the random-effects model. At the same time, the pooled standardized mean difference (SMD) with 95% CI was used for the meta-analysis of the PPARG Pro12Ala polymorphism and blood pressure.

Results

Finally, Fifteen papers (seventeen studies) including 4,151 cases and 4,997 controls to evaluate the association of the PPARGPro12Ala polymorphism and EH risk, were included in this study. Overall, the results suggested that Ala allele was associated with the decreased EH risk (for allelic model, OR = 0.757, 95%CI: 0.624–0.918, P = 0.005; for dominant model, OR = 0.771, 95%CI: 0.627–0.946, P = 0.013). The subgroup analysis stratified by ethnicity showed that the significant association between the PPARG Pro12Ala polymorphism and EH was only detected in the Asian subgroup. There was no difference in blood pressure values between Ala carriers and non-carriers. For the C161T polymorphism, only 5 studies comprising 1,118 cases and 1,357 controls met the inclusion criteria. The overall results showed that the PPARG C161T polymorphism was not associated with the risk of EH. But in the subgroup analysis, we found that the PPARG C161T polymorphism significantly associated with the risk of EH in the Asian subgroup (for allelic model, OR = 0.719, 95% CI: 0.537–0.963, P = 0.027; for dominant model, OR = 0.653, 95% CI: 0.439–0.972, P = 0.036).

Conclusion

Our meta-analysis suggested that the PPARG polymorphisms might be associated with the risk of EH.

Impact of the PPAR gamma-2 gene polymorphisms on the metabolic state of postmenopausal women

The relationship Pro12Ala (rs1801282) and C1431T (rs3856806) polymorphisms of PPAR gamma-2 with glucose and lipid metabolism is not clear after menopause. We investigated the impact of the Pro12Ala and C1431T silent substitution in the 6th exon in PPAR gamma-2 gene on nutritional and metabolic status in 271 postmenopausal women (122 lean and 149 obese). The general linear model (GLM) approach to the two-way analysis of variance (ANOVA) was used to infer the interactions between the analysed genotypes. The frequency of the Pro-T haplotype was higher in obese than in lean women (p less than 0.0349). In the analysed GLM models according to obesity status, the C1431C genotype was related to a lower glucose concentration (beta=-0.2103) in lean women, and to higher folliculotropic hormone FSH levels (beta=0.1985) and lower waist circumferences (beta=-0.1511) in obese women. The influence of C1431C was present regardless of the occurrence of the Pro12Ala polymorphism. The co-existence of the C1431C and Pro12Pro genotypes was related to lower values for triceps skinfold thickness compared those for the T1241/X and Ala12/X polymorphisms (beta=-0.1425). The presence of C1431C decreased the differences between triceps values that were determined by Pro or Ala allele. In conclusion, C1431T polymorphism seems to have a more essential influence on anthropometric and biochemical parameters than is the case with Pro12Ala polymorphism.

Maternal Metabolism and Vascular Adaptation in Pregnancy: The PPAR Link

Current therapies for pregnancy-related hypertension and its complications remain inadequate, although an increasing role for maternal susceptibility is becoming evident. Systemic vascular dysfunction in response to imbalances in angiogenic, inflammatory, and constricting factors is implicated in the pathogenesis of gestational hypertension, and growing evidence now links these factors with maternal metabolism. In particular, the crucial role of peroxisome proliferator-activated receptors (PPARs) in maternal vascular adaptation provides further insights into how obesity and gestational diabetes may be linked to pregnancy-induced hypertension and preeclampsia. This is especially important given the rapidly growing prevalence of obesity during pregnancy, and highlights a new approach to treat pregnancy-related hypertension and its complications.

The Gene-Diet Associations in Postmenopausal Women with Newly Diagnosed Dyslipidemia

OBJECTIVES

The aim of this study was to determine the relationship between polymorphisms of peroxisome proliferator activated receptor - PPAR gamma-2 (Pro12Ala, C1431T) and beta 3-adrenergic receptor - ADRB3 (Trp64Arg) and dietary habits in a group of postmenopausal women who were not under hypolipidemic treatment.

DESIGN

Genetic, nutritional and anthropometric parameters were measured in 213 dyslipidemic (LDL ≥115 mg/dL) and 58 normolipidemic (LDL<115) postmenopausal women. The PCR-RFLP method were used to determine the distributions of selected alleles and genotype frequencies. Dietary intake of basic components and fatty acids was obtained from a 7-day weighed food record and the bio-impedance method was used to determine nutritional status.

RESULTS

Nearly 79% of analyzed women were in the first-time-diagnosed dyslipidemic state. The dyslipidemic subjects were characterized with higher intake of energy, fat, and saturated fatty acids (SFA). The analysis of the same polymorphisms showed association at the P value <0.05 with nutrients (fat, SFA, and polyunsaturated fatty acid - PUFA and saccharose) and elevated LDL level. Higher PUFA intake in a group of women with the protective Ala12/X polymorphism did not increase the risk of dyslipidemia even though they were characterized by visceral distribution of fat. The Arg64/X polymorphism and higher intake of energy, fat, and arachidic acid intake (C20:0) were associated with dyslipidemic state.

CONCLUSION

Both nutritional and genetic factors are related to lipid profile. The identification of gene-diet associations is likely to provide useful information about the etiology of postmenopausal dyslipidemia and help in effective treatment.

Genetic Background, Adipocytokines, and Metabolic Disorders in Postmenopausal Overweight and Obese Women

The relationship between the genetic background, adipocytokines, and metabolic state in postmenopausal women has not yet been fully described. The aim of this study was to determine the relationship between PPAR gamma-2 (Pro12Ala, C1431T) and ADRB3 (Trp64Arg) polymorphisms and serum adipocytokines (adiponectin, visfatin, and resistin) and metabolic disorders in 176 postmenopausal women with increased body mass (BMI ≥ 25 kg m(-2)). The distributions of selected alleles and genotype frequencies were determined with the PCR-RFLP method. The bioimpedance method was used to determine nutritional status, and enzyme-linked immunosorbent assays were applied to determine serum concentrations of adipocytokines. Viscerally obese postmenopausal women had higher body mass, body fat content, serum glucose, insulin, total cholesterol, LDL, triglycerides, uric acid, and HOMA-IR and a higher prevalence of the Ala12 allele. In models based on cytokine concentration, higher body mass and glucose concentration (visfatin model, p = 0.008) and higher insulin and triglyceride levels (resistin model, p = 0.002) were observed in visceral fat deposition and this was potentiated by the presence of the T1431 allele. In resistin models, co-existence of Ala12/X polymorphisms with the T1431 allele was associated with higher resistin and triglyceride concentrations (p = 0.045). In postmenopausal women, metabolic parameters are mainly determined by the distribution of body fat, but Ala12/X polymorphism may increase the metabolic disorders and this effect can be enhanced by the T1431 allele.