The Pro12Ala polymorphism in the peroxisome proliferator-activated receptor gamma-2 gene (PPARγ2) is associated with increased risk of coronary artery disease: a meta-analysis

Immunogenetic Aspects of Sarcopenic Obesity

Sarcopenic obesity (SO) is a combination of obesity and sarcopenia, with diagnostic criteria defined as impaired skeletal muscle function and altered body composition (e.g., increased fat mass and reduced muscle mass). The mechanism of SO is not yet perfectly understood; however, the pathogenesis includes aging and its complications, chronic inflammation, insulin resistance (IR), and hormonal changes. Genetic background is apparent in the pathogenesis of isolated obesity, which is most often polygenic and is characterized by the additive effect of various genetic factors. The genetic etiology has not been strictly established in SO. Still, many data confirm the existence of pathogenic gene variants, e.g., Fat Mass and Obesity Associated Gene (FTO), beta-2-adrenergic receptor (ADRB2) gene, melanocortin-4 receptor (MC4R) and others with obesity. The literature on the role of these genes is scarce, and their role has not yet been thoroughly established. On the other hand, the involvement of systemic inflammation due to increased adipose tissue in SO plays a significant role in its pathophysiology through the synthesis of various cytokines such as monocyte chemoattractant protein-1 (MCP-1), IL-1Ra, IL-15, adiponectin or CRP. The lack of anti-inflammatory cytokine (e.g., IL-15) can increase SO risk, but further studies are needed to evaluate the exact mechanisms of implications of various cytokines in SO individuals. This manuscript analyses various immunogenetic and non-genetic factors and summarizes the recent findings on immunogenetics potentially impacting SO development.

Heterogeneity in quiescent Müller glia in the uninjured zebrafish retina drive differential responses following photoreceptor ablation

Introduction

Loss of neurons in the neural retina is a leading cause of vision loss. While humans do not possess the capacity for retinal regeneration, zebrafish can achieve this through activation of resident Müller glia. Remarkably, despite the presence of Müller glia in humans and other mammalian vertebrates, these cells lack an intrinsic ability to contribute to regeneration. Upon activation, zebrafish Müller glia can adopt a stem cell-like state, undergo proliferation and generate new neurons. However, the underlying molecular mechanisms of this activation subsequent retinal regeneration remains unclear.

Methods/Results

To address this, we performed single-cell RNA sequencing (scRNA-seq) and report remarkable heterogeneity in gene expression within quiescent Müller glia across distinct dorsal, central and ventral retina pools of such cells. Next, we utilized a genetically driven, chemically inducible nitroreductase approach to study Müller glia activation following selective ablation of three distinct photoreceptor subtypes: long wavelength sensitive cones, short wavelength sensitive cones, and rods. There, our data revealed that a region-specific bias in activation of Müller glia exists in the zebrafish retina, and this is independent of the distribution of the ablated cell type across retinal regions. Notably, gene ontology analysis revealed that injury-responsive dorsal and central Müller glia express genes related to dorsal/ventral pattern formation, growth factor activity, and regulation of developmental process. Through scRNA-seq analysis, we identify a shared genetic program underlying initial Müller glia activation and cell cycle entry, followed by differences that drive the fate of regenerating neurons. We observed an initial expression of AP-1 and injury-responsive transcription factors, followed by genes involved in Notch signaling, ribosome biogenesis and gliogenesis, and finally expression of cell cycle, chromatin remodeling and microtubule-associated genes.

Discussion

Taken together, our findings document the regional specificity of gene expression within quiescent Müller glia and demonstrate unique Müller glia activation and regeneration features following neural ablation. These findings will improve our understanding of the molecular pathways relevant to neural regeneration in the retina.

Molecular Dynamics Simulation and Essential Dynamics of Deleterious Proline 12 Alanine Single-Nucleotide Polymorphism in PPARγ2 Associated with Type 2 Diabetes, Cardiovascular Disease, and Nonalcoholic Fatty Liver Disease

Background. Peroxisome proliferator-activated receptor-γ (PPARγ) gene is located at 3p25 position. PPARγ functions as the master regulator of glucose homeostasis and lipoprotein metabolism, and recent studies have reported that it is involved in various metabolic diseases such as diabetes mellitus, hyperlipidemia, coronary artery disease (CAD), and nonalcoholic fatty liver disease (NAFLD). PPARγ1 and PPARγ2 are necessary for the development of adipose tissue and insulin sensitivity regulation. But PPARγ2 is the isoform that was controlled in response to nutrient intake and obesity. Methodology. In this study, we used computational techniques to show the impact of Pro12Ala polymorphism on PPARγ2. The 3-D structure of PPARγ2 was modeled using I-TASSER server. The modeled structure was validated with the ZLab server, and the mutation was created with SPDB viewer. Stability prediction tools were used. Molecular dynamics simulation (MDS) was used to understand the structural and functional behavior of the wild type and mutant. Essential dynamics was also applied. Results and Conclusions. Stability prediction tools were showed that this mutation has a destabilizing effect on the PPARγ2 structure. The RMSD, RMSF, Rg, SASA, and DSSP were in line with H-bond results that showed less flexibility in the mutant structure. Essential dynamics was used to verify MDS results. Pro12Ala polymorphism leads to rigidity of the PPARγ2 protein and might disturb the conformational changes and interactions of PPARγ2 and results in type 2 diabetes mellitus (T2DM), CAD, and NAFLD. This study can help scientists to develop a drug therapy against these diseases.

ASSOCIATION BETWEEN PRO12ALa POLYMORPHISM OF PPARγ2 GENE AND CORONARY ARTERY DISEASE IN IRANIAN POPULATION WITH TYPE TWO DIABETES MELLITUS

CONTEXT

Coronary artery disease (CAD) is one of the common diseases in patients with type two diabetes mellitus (T2DM). The nuclear hormone receptor peroxisome proliferator-activated receptor-gamma (PPARγ) plays a vital role in dyslipidemia, and oxidative stress is involved in atherogenesis.

OBJECTIVE

The study aimed to determine the association between Pro12Ala polymorphism of the PPARγ2 gene(rs1801282) and CAD risk in T2DM patients in the Iranian population.

DESIGN

A group of 145 T2DM patients with a history of CAD were enrolled, together with 145 sex and gender-matched individuals who had neither CAD nor history of T2DM who were enrolled in a case-control study.

SUBJECTS AND METHODS

Polymerase chain reaction-restriction fragment length polymorphism technique was applied to genotype the PPARγ2 gene polymorphisms. Statistical analysis was done using SPSS version 22.

RESULTS

CC and GC genotypes of Pro12Ala had a higher frequency in the control and case groups, respectively. The GC genotype was associated with a significantly increased CAD risk compared to the CC genotype (adjusted OR= 2.66, 95% CI = 1.5-29.5, p<0.01). The mean triglycerides and total cholesterol level were significantly higher in the CC genotype than the GC genotype in both case and control groups (p<0.05). The mean level of fasting blood glucose was significantly higher in the CC genotype compared to GC genotype in the case group (p<0.05). The mean of creatinine, lipid profiles, microalbuminuria, and hemoglobin A1c had no significant difference between CC and GC genotypes in both groups (p>0.05).

CONCLUSION

PPARγ2 Pro12Ala polymorphism could be an essential indicator for the increased risk of CAD in the Iranian people with T2DM.

PPARγ Gene Polymorphisms, Metabolic Disorders, and Coronary Artery Disease

Being activated by endogenous and exogenous ligands, nuclear receptor peroxisome proliferator-activated receptor gamma (PPARγ) enhances insulin sensitivity, promotes adipocyte differentiation, stimulates adipogenesis, and has the properties of anti-atherosclerosis, anti-inflammation, and anti-oxidation. The Human PPARγ gene (PPARG) contains thousands of polymorphic loci, among them two polymorphisms (rs10865710 and rs7649970) in the promoter region and two polymorphisms (rs1801282 and rs3856806) in the exonic region were widely reported to be significantly associated with coronary artery disease (CAD). Mechanistically, PPARG polymorphisms lead to abnormal expression of PPARG gene and/or dysfunction of PPARγ protein, causing metabolic disorders such as hypercholesterolemia and hypertriglyceridemia, and thereby increasing susceptibility to CAD.

G Allele of the rs1801282 Polymorphism in PPARγ Gene Confers an Increased Risk of Obesity and Hypercholesterolemia, While T Allele of the rs3856806 Polymorphism Displays a Protective Role Against Dyslipidemia: A Systematic Review and Meta-Analysis

BACKGROUND

The relationships between the rs1801282 and rs3856806 polymorphisms in nuclear receptor peroxisome proliferator-activated receptor gamma (PPARγ) gene and obesity indexes as well as serum lipid levels have been extensively investigated in various studies, but the results were inconsistent and even contradictory.

METHODS

PubMed, Google Scholar, Embase, Cochrane Library, Web of Science, Wanfang, CNKI and VIP databases were searched for eligible studies. The random-effTPDEects model was used, and standardized mean difference (SMD) with 95% confidence interval (CI) was calculated to estimate the differences in obesity indexes and serum lipid levels between the subjects with different genotypes in a dominant model. Heterogeneity among studies was assessed by Cochran's x²-based Q-statistic test. Publication bias was identified by using Begg's test.

RESULTS

One hundred and twenty studies (70,317 subjects) and 33 studies (18,353 subjects) were identified in the analyses for the rs1801282 and rs3856806 polymorphisms, respectively. The G allele carriers of the rs1801282 polymorphism had higher levels of body mass index (SMD = 0.08 kg/m², 95% CI = 0.04 to 0.12 kg/m², p < 0.001), waist circumference (SMD = 0.12 cm, 95% CI = 0.06 to 0.18 cm, p < 0.001) and total cholesterol (SMD = 0.07 mmol/L, 95% CI = 0.02 to 0.11 mmol/L, p < 0.01) than the CC homozygotes. The T allele carriers of the rs3856806 polymorphism had lower levels of low-density lipoprotein cholesterol (SMD = -0.09 mmol/L, 95% CI = -0.15 to -0.03 mmol/L, p < 0.01) and higher levels of high-density lipoprotein cholesterol (SMD = 0.06 mmol/L, 95% CI = 0.02 to 0.10 mmol/L, p < 0.01) than the CC homozygotes.

CONCLUSIONS

The meta-analysis suggests that the G allele of the rs1801282 polymorphism confers an increased risk of obesity and hypercholesterolemia, while the T allele of the rs3856806 polymorphism displays a protective role against dyslipidemia, which can partly explain the associations between these polymorphisms and cardiovascular disease.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/, identifier [CRD42022319347].

Burn injury induces elevated inflammatory traffic: the role of NF-κB

A burn insult generally sustains a hypovolemic shock due to a significant loss of plasma from the vessels. The burn injury triggers the release of various mediators, such as reactive oxygen species (ROS), cytokines, and inflammatory mediators. Damage-associated molecular patterns (DAMPs) and pathogen-associated molecular patterns (PAMPs), stemming from foreign microbial discharge and damaged tissue or necrotic cells from the burn-injured site, enter the systemic circulation, activate toll-like receptors (TLRs), and trigger the excessive secretion of cytokines and inflammatory mediators. Inflammation plays a vital role in remodeling an injured tissue, detoxifying toxins, and helps in the healing process. A transcription factor, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), contributes to a variety of physiological and pathological conditions, including immune response, cell death, cell survival, and inflammatory processes. During the pathogenesis of a burn wound, upregulation of various cytokines and growth factors lead to undesirable tissue inflammation. Thus, NF-κB, a dominant moderator of inflammation, needs to be altered to prove beneficial to the treatment of burns or other inflammation-associated diseases. This review addresses the relationship between NF-κB and elevated inflammation in a burn condition that could potentially be altered to induce an early wound-healing mechanism of burn wounds.

Metabolic Effects of Oxytocin

There is growing evidence that oxytocin (OXT), a hypothalamic hormone well recognized for its effects in inducing parturition and lactation, has important metabolic effects in both sexes. The purpose of this review is to summarize the physiologic effects of OXT on metabolism and to explore its therapeutic potential for metabolic disorders. In model systems, OXT promotes weight loss by decreasing energy intake. Pair-feeding studies suggest that OXT-induced weight loss may also be partly due to increased energy expenditure and/or lipolysis. In humans, OXT appears to modulate both homeostatic and reward-driven food intake, although the observed response depends on nutrient milieu (eg, obese vs. nonobese), clinical characteristics (eg, sex), and experimental paradigm. In animal models, OXT is anabolic to muscle and bone, which is consistent with OXT-induced weight loss occurring primarily via fat loss. In some human observational studies, circulating OXT concentrations are also positively associated with lean mass and bone mineral density. The impact of exogenous OXT on human obesity is the focus of ongoing investigation. Future randomized, placebo-controlled clinical trials in humans should include rigorous, standardized, and detailed assessments of adherence, adverse effects, pharmacokinetics/pharmacodynamics, and efficacy in the diverse populations that may benefit from OXT, in particular those in whom hypothalamic OXT signaling may be abnormal or impaired (eg, individuals with Sim1 deficiency, Prader-Willi syndrome, or craniopharyngioma). Future studies will also have the opportunity to investigate the characteristics of new OXT mimetic peptides and the obligation to consider long-term effects, especially when OXT is given to children and adolescents. (Endocrine Reviews XX: XX - XX, 2020).

Role of TCF7L2 and PPARG2 Gene Polymorphisms in Renal and Cardiovascular Complications among Patients with Type 2 Diabetes: A Cohort Study

BACKGROUND

The emerging renal and cardiovascular complications of type 2 diabetes (T2DM) genetics involves differently assembled gene variants including transcription factor 7-like 2 (TCF7L2) and peroxisome proliferator-activated receptor gamma 2 (PPARG2) polymorphisms. However, the relevance of these genes for complication prediction has not been extensively tested.

METHODS

We analyzed the SNP rs7903146 variants in TCF7L2 and PPARG2 gene polymorphisms for their contribution to the incidence of chronic kidney disease (CKD) and cardiovascular complications in a prospective cohort study. All T2DM patients were followed up to estimate the glomerular filtration rate and cardiovascular outcomes. Cox proportional hazards regression models were used to estimate the genotype effect on the incidence of CKD and vascular complications.

RESULTS

A total of 422 patients were included. SNP rs7903146 variants in the TCF7L2 gene were classified into 3 groups: CC, 385 patients (91.2%), CT, 32 patients (7.6%), and TT, 5 patients (1.2%), while in the PPARG2 gene they were classified into 2 groups: Pro12Pro, 404 patients (95.7%) and Pro12Ala, 18 patients (4.3%). The prevalence of CKD, cardiovascular disease, and death at the end of the 5-year follow-up was 16.8, 29, and 7.9%, respectively. The Pro12Ala variant of the PPARG2 gene was significantly associated with increased CKD risk at the end of the study (adjusted HR 3.45, 95% CI 1.01-11.77, p = 0.046); it showed a significant association with increased cerebrovascular risk, but not cardiovascular disease and mortality. No genotype effect of rs7903146 in the TCF7L2 gene was apparent on renal and cardiovascular complications, except the TT variant of rs7903146 increased cardiovascular events when compared with the non-TT variant.

CONCLUSION

The findings of our study were that the Pro12Ala variant in the PPARG2 gene was associated with risk of developing CKD and cerebrovascular disease in Asian T2DM subjects in a prospective cohort study. The TCF7L2 polymorphism was not associated with cardiovascular outcomes.

PPARA, PPARD and PPARG gene polymorphisms in patients with unstable angina

BACKGROUND

Peroxisome proliferator-activated receptors (PPARs) include the nuclear receptor superfamily of ligand-activated transcription factors involved in several metabolic processes, including carbohydrate and lipid metabolism.

MATERIAL AND METHODS

In this study we examined PPARA: rs4253778, rs1800206, PPARD: rs2267668, rs2016520, rs1053049, PPARG rs1801282 and PPARGC1A rs8192678 polymorphisms in patients with unstable angina. This study included 246 patients with unstable angina confirmed by coronary angiography (defined by >70% stenosis in at least one major coronary artery) and 189 healthy controls.

RESULTS

We observed statistically significant difference in distribution of PPARG rs1801282 genotypes and alleles between patients and control group. Among patients there was the increased frequency of CG and GG genotypes and G alleles. The association between PPARG rs1801282 G allele and unstable angina was confirmed in multivariate regression analysis. There were no statistically significant differences in the distributions of other studied polymorphisms between patients with unstable angina and the control group.

CONCLUSIONS

The results of our study suggest the association between PPARG rs1801282 G allele and unstable angina in Polish population.

PPARG2 Pro12Ala and TNFα -308G>A Polymorphisms Are Not Associated with Heart Failure Development in Patients with Ischemic Heart Disease after Coronary Artery Bypass Grafting

TNFα and PPARγ are important modulators of metabolism, inflammation, and atherosclerosis. Coronary artery disease is the leading cause of heart failure (HF). The aim of the study was to assess whether polymorphisms of the TNFα (-308G>A) and PPARG2 (Pro12Ala) genes are associated with the risk of developing HF by patients with ischemic heart disease. Methods. 122 patients without HF (aged 63 ± 8.8 years, 85% males) with confirmed coronary artery disease qualified for coronary bypass grafting were enrolled in the study. After the procedure, they were screened for cardiac parameters. Those with elevated NT-proBNP or diminished left ventricular ejection fraction during follow-up were assigned to the HF group (n=78), and the remaining ones to the non-HF group (n=44). The TNFα -308G>A and PPARG2 Pro12Ala polymorphisms were detected using the TaqMan method. Results. The distributions of TNFα -308G>A and PPARG2 Pro12Ala did not differ between the HF and non-HF groups (-308G>A: 16% vs. 11.4% of alleles; Pro12Ala: 23.9% vs. 20.5% of alleles, respectively). IL-6 concentration in the plasma of TNFα A-allele carriers at months 1 and 12 after CABG was higher in the HF group compared to the non-HF group (1 month after CABG: 5.3 ± 3.4 vs. 3.1 ± 2.9, p<0.05; 12 months after CABG: 4.2 ± 3,9 vs. 1.4 ± 1.2, p<0.01, respectively). Both polymorphisms were not related to changes in the plasma TNFα concentration or other parameters related to HF. Conclusions. Our study did not reveal any correlation between the PPARG2 Pro12Ala and TNFα -308G>A polymorphisms and development of HF in patients with ischemic heart disease after coronary bypass grafting.

Gene-gene interaction between PPARG and CYP1A1 gene on coronary artery disease in the Chinese Han Population

AIMS

To observe the influence of the peroxisome proliferator-activator receptor-G (PPAR-G) gene and cytochrome P4501A1 (CYP1A1) single-nucleotide polymorphisms (SNPs), and interactions among several SNPs on coronary artery disease (CAD) risk.

METHODS

A total of 1106 participants (including 583 males and 523 females) including 550 CAD patients and 556 control subjects were recruited in this study, and the mean age for these participants was 55.5 ± 11.8 years old. Logistic regression was used to observe association of SNP within PPARG and CYP1A1 with CAD risk and GMDR model was used to screen the best interaction combinations.

RESULTS

CAD susceptibility was higher in those with homozygous mutant of rs10865710, rs1805192 and rs4646903 than those with wild-type homozygotes, OR (95%CI) were 1.47 (1.15-1.92), 1.69 (1.27-2.09) and 1.72 (1.35-2.32), respectively. We also found a significant two-locus model involving rs1805192 and rs4646903 (p = 0.0107), and the cross-validation consistency of this locus model was 10 of 10, the testing accuracy of this model is 62.17%. Logistic regression shown that CAD risk was the highest in those with rs1805192- Pro/Ala or Ala/Ala and rs4646903- AG+GG genotype, and was lowest in those with rs1805192- Pro/ Pro and rs4646903- AA genotype, OR(95%CI) = 3.56 (1.91-5.42).

CONCLUSIONS

Polymorphism in rs10865710, rs1805192 and rs4646903 and interaction between rs1805192 and rs4646903 were related with increased CAD susceptibility.

Association between peroxisome proliferator-activated receptor-alpha, delta, and gamma polymorphisms and risk of coronary heart disease: A case-control study and meta-analysis

OBJECTIVES

Risk of coronary heart disease (CHD) has been suggested to be associated with polymorphisms of peroxisome proliferator-activated receptors (PPARs), while the results were controversial. We aimed to systematically assess the association between PPAR polymorphisms and CHD risk.

METHODS

A case-control study with 446 subjects was conducted to evaluate the association between CHD risk and C161T polymorphism, which was of our special interest as this polymorphism showed different effects on risks of CHD and acute coronary syndrome (ACS). Meta-analyses were conducted to assess all PPAR polymorphisms. Either a fixed- or a random-effects model was adopted to estimate overall odds ratios (ORs).

RESULTS

In the case-control study, T allele carriers of C161T polymorphism were not significantly associated with CHD risk (Odds ratio (OR) = 0.74, 95% confidence interval (CI) 0.47-1.15, P = 0.19), while T allele carriers showed higher risk of ACS (OR = 1.63, 95% CI 1.00-2.65, P = 0.048). The meta-analysis indicated that compared with CC homozygous, T allele carriers had lower CHD risk (OR = 0.69, 95% CI 0.59-0.82, P < 0.001) but higher ACS risk (OR = 1.43, 95% CI 1.09-1.87, P = 0.010). Three other polymorphisms were also found to be significantly associated with CHD risk under dominant model: PPAR-alpha intron 7G/C polymorphism (CC+GC vs GG, OR 1.42, 95% CI 1.13-1.78, P = 0.003), L162V polymorphism (VV+LV vs LL, OR 0.74, 95% CI 0.56-0.97, P = 0.031), and PPAR-delta +294T/C polymorphism (CC+TC vs TT, OR 1.51, 95% CI 1.12-2.05, P = 0.007).

CONCLUSIONS

The results suggested that PPAR-alpha intron 7G/C and L162V, PPAR-delta +294T/C and PPAR-gamma C161T polymorphisms could affect CHD susceptibility, and C161T polymorphism might have different effects on CHD and ACS.

Is the Mouse a Good Model of Human PPARγ-Related Metabolic Diseases?

With the increasing number of patients affected with metabolic diseases such as type 2 diabetes, obesity, atherosclerosis and insulin resistance, academic researchers and pharmaceutical companies are eager to better understand metabolic syndrome and develop new drugs for its treatment. Many studies have focused on the nuclear receptor peroxisome proliferator-activated receptor gamma (PPARγ), which plays a crucial role in adipogenesis and lipid metabolism. These studies have been able to connect this transcription factor to several human metabolic diseases. Due to obvious limitations concerning experimentation in humans, animal models—mainly mouse models—have been generated to investigate the role of PPARγ in different tissues. This review focuses on the metabolic features of human and mouse PPARγ-related diseases and the utility of the mouse as a model.

Genetics of coronary artery disease and myocardial infarction

Atherosclerotic coronary artery disease (CAD) comprises a broad spectrum of clinical entities that include asymptomatic subclinical atherosclerosis and its clinical complications, such as angina pectoris, myocardial infarction (MI) and sudden cardiac death. CAD continues to be the leading cause of death in industrialized society. The long-recognized familial clustering of CAD suggests that genetics plays a central role in its development, with the heritability of CAD and MI estimated at approximately 50% to 60%. Understanding the genetic architecture of CAD and MI has proven to be difficult and costly due to the heterogeneity of clinical CAD and the underlying multi-decade complex pathophysiological processes that involve both genetic and environmental interactions. This review describes the clinical heterogeneity of CAD and MI to clarify the disease spectrum in genetic studies, provides a brief overview of the historical understanding and estimation of the heritability of CAD and MI, recounts major gene discoveries of potential causal mutations in familial CAD and MI, summarizes CAD and MI-associated genetic variants identified using candidate gene approaches and genome-wide association studies (GWAS), and summarizes the current status of the construction and validations of genetic risk scores for lifetime risk prediction and guidance for preventive strategies. Potential protective genetic factors against the development of CAD and MI are also discussed. Finally, GWAS have identified multiple genetic factors associated with an increased risk of in-stent restenosis following stent placement for obstructive CAD. This review will also address genetic factors associated with in-stent restenosis, which may ultimately guide clinical decision-making regarding revascularization strategies for patients with CAD and MI.

Maternal PPARG Pro12Ala polymorphism is associated with infant's neurodevelopmental outcomes at 18 months of age

BACKGROUND

Peroxisome proliferator activated receptors (PPARs) are ligand activated transcription factors with crucial functions in lipid homeostasis, glucose metabolism, anti-inflammatory processes, placental development, and are involved in cognitive functions and neurodegenerative diseases. Polymorphisms in PPAR genes are shown to influence the activity of these receptors.

AIMS

1) To examine the association of PPARG Pro12Ala polymorphism in pregnant women and their offspring on infant's neurodevelopmental outcomes during the first 18 months of life; 2) to determine the influence of Pro12Ala polymorphism on fatty acid concentrations in plasma phospholipids and placental tissue.

STUDY DESIGN

138 mother-infant pairs from the PREOBE observational study were genotyped for PPARG Pro12Ala. Plasma phospholipids and placental fatty acid concentrations were measured at delivery. Infants' neuropsychological assessment at 6 and 18 months of age was performed using Bayley III.

RESULTS

The effect of Pro12Ala on infant's neurodevelopmental outcomes was detected at 18 months, but not at 6 months of age. 18 months old infants born to mothers with wild-type Pro12 genotype had better cognitive (OR=5.11, 95% CI: 1.379-18.96, p=0.015), language (OR=3.41, 95% CI: 1.35-11.24, p=0.044), and motor development scores (OR=4.77, 95% CI: 1.243-18.33, p=0.023) than the Ala allele carriers. Pro12Ala variants did not seem to affect fatty acids concentrations in blood nor in placenta at delivery.

CONCLUSIONS

Infants born to mothers with Pro12 genotype have better neurodevelopmental outcomes at 18 months of age than Ala allele carriers, indicating a long-term transplacental action of PPARγ variants on foetal brain development.

Association between Peroxisome Proliferator-activated Receptor Gamma Gene Polymorphisms and Atherosclerotic Diseases: A Meta-analysis of Case-control Studies

AIM

The aim of this study was to perform a meta-analysis to investigate the association between PPARγ rs1801282/rs3856806 polymorphisms and atherosclerotic diseases.

METHODS

The meta-analysis was performed by searching the PubMed, Embase and Web of Science databases from the first available year to September 10, 2013. Additionally, reference lists from the identified articles, reviews and abstracts presented at the meetings of related scientific societies were also checked. All case-control studies investigating the association between PPARγ rs1801282/rs3856806 polymorphisms and the risk of atherosclerotic disease were included. The association was assessed according to the odds ratio (OR) with a 95% confidence interval (CI). Publication bias was analyzed using Begg's funnel plot and Egger's regression test.

RESULTS

A total of 29 studies reporting PPARγ rs1801282/rs3856806 polymorphism were included in the final meta-analysis. Neither the rs1801282 (Pro12Ala) nor rs3856806 (C161T) polymorphisms showed any significant associations with susceptibility to atherosclerotic diseases. In the meta-analysis performed to assess the association between the rs3856806 gene polymorphism and atherosclerotic disease based on ethnicity and the type of disease, significant associations were found in the Caucasian subgroup, Asian, CAD and MI subgroups.

CONCLUSIONS

The present data suggest that there is no statistical evidence of a significant association between the PPARγ gene rs1801282/rs3856806 polymorphism and the risk of atherosclerotic disease. In contrast, the rs3856806 polymorphism was associated with an increased risk in the Caucasian and MI subgroups, whereas decreased risks were noted in the Asian and CAD subgroups. Due to significant between-study heterogeneity, further studies with a larger sample size involving homogeneous AS patients and well-matched controls are required in the future.

Copy number variation of the Lipoprotein(a) (LPA) gene is associated with coronary artery disease in a southern Han Chinese population

Copy number variations (CNVs), genomic duplication or deletion events occurring at larger than 1 kb scale, contribute to the complex diseases substantially. Lipoprotein(a) [Lp(a)] is a major inherited risk factor for atherosclerosis and coronary artery disease (CAD). We investigated the association between a CNV of the Lp(a) (LPA) gene and CAD. The case-control study included 271 CAD patients and 207 controls diagnosed by coronary angiography. A taqman real-time fluorescence PCR based technique was developed according to the 2 × 2(-ΔΔCt±SD) calculation method. We detected LPA CNVs with a range of 1, 2 and 3. The 1 copy number carriers had a significantly reduced risk of CAD compared with those with 2 copy number after adjusting for the confounding factors (P < 0.001, OR = 0.38, 95% CI 0.23-0.64). Further stratified analyses suggested a significant protective effect of the 1 copy number in the elderly population (P = 0.008), females (P = 0.007) as well as in populations with non-hyperlipidemia (P = 0.003), hypertension (P = 0.001), non-smoking (P < 0.001) and high Lp(a) (≥ 0.3 g/L) levels (P = 0.001). The 1 copy number of the LPA gene may be an independent protective factor of CAD in a southern Han Chinese population, particularly in females and the elderly.

PPARγ2 Pro12Ala polymorphism was associated with favorable cardiometabolic risk profile in HIV/HCV coinfected patients: a cross-sectional study

Background

Peroxisome proliferator-activated receptor gamma-2 gene (PPARγ2) rs1801282 (Pro12Ala) polymorphism has been associated with lower risk of metabolic disturbance and atherosclerosis. The aim of this study was to analyze the association between the Pro12Ala polymorphism and cardiometabolic risk factors in human immunodeficiency virus (HIV)/Hepatitis C virus (HCV)-coinfected patients.

Methods

We carried out a cross-sectional study on 257 HIV/HCV coinfected patients. PPARγ2 polymorphism was genotyped by GoldenGate® assay. The main outcome measures were: i) serum lipids (cholesterol, triglycerides, high-density lipoprotein (HDL-C), low-density lipoprotein (LDL-C), LDL-C/HDL-C, and atherogenic index (AI)); ii) homeostatic model assessment (HOMA-IR) values; iii) serum adipokines (leptin, adiponectin, resistin, plasminogen activator inhibitor-1(PAI-1), hepatic growth factor (HGF), and nerve growth factor (NGF)). Generalized Linear Models (GLM) with gamma distribution (log-link) were used to investigate the association between PPARγ2 polymorphism and continuous outcome variables. This test gives the differences between groups and the arithmetic mean ratio (AMR) in continuous outcome variables between groups.

Results

The rs1801282 CG/GG genotype was associated with low values of cholesterol (adjusted arithmetic mean ratio (aAMR) = 0.87 (95% of confidence interval (95% CI) = 0.79; 0.96); p = 0.004) and LDL-C (aAMR = 0.79 (95% CI = 0.68; 0.93); p = 0.004). Furthermore, rs1801282 CG/GG was associated with low values of HOMA-IR (aAMR = 0.69 (95% CI = 0.49; 0.98); p = 0.038) among patients with significant liver fibrosis (F ≥ 2). Moreover, rs1801282 CG/GG was also associated with low serum values of hepatic growth factor (HGF) (aAMR = 0.61 (95% CI = 0.39; 0.94); p = 0.028), and nerve growth factor (NGF) (aAMR = 0.47 (95% CI = 0.26; 0.84); p = 0.010). The serum levels of leptin, adiponectin, resistin, and PAI-1 did not show significant differences.

Conclusions

The presence of PPARγ2 rs1801282 G allele (Ala variant) was associated with a protective cardiometabolic risk profile versus CC genotype in HIV/HCV-coinfected patients. Thus, PPARγ2 rs1801282 polymorphism may play a significant role in the development of metabolic disorders in HIV/HCV coinfected patients, and might have an influence on the cardiovascular risk.

Association of peroxisome proliferator-activated receptorγ gene Pro12Ala and C161T polymorphisms with cardiovascular risk factors in maintenance hemodialysis patients

The Pro12Ala and C161T polymorphisms in peroxisome proliferator-activated receptor γ (PPARγ) have been shown to be associated with carotid artery atherosclerosis. It remains unclear whether these two polymorphisms are associated with risk factors for cardiovascular disease (CVD) in hemodialysis (HD) patients. Therefore, the PPARγ genotypes in 99 HD patients and 149 controls were determined, and clinical characteristics among the different genotypes were compared. We found that the frequency of the Pro12Ala and C161T polymorphisms in HD patients was similar to that in healthy controls, but C161T polymorphism and T allele frequencies in HD patients with CVD were lower than that in HD patients without CVD. Carotid artery plaque (CAP) and carotid intima-media thickness (CIMT) in HD patients with CT + TT or Pro12Ala genotypes were also less than that in patients with CCor Pro12Pro genotypes, respectively. HD patients with CT + TT genotype had lower serum C reactive protein (CRP) levels, as well as higher triceps skin fold (TSF) thickness, mid arm circumference (MAC) and mean mid arm circumference (MMAC) than HD patients with CC genotype (P < 0.05). Moreover, CIMT of the Pro12Ala-CT161 subgroup was less than the Pro12Pro-CC161 and Pro12Pro-CT161 subgroup, and, CAP amounts of the Pro12Ala-CT161 subgroup was less than the Pro12Pro-CC161 subgroup. Our results indicate that the Pro12Ala and C161T polymorphisms were associated with some important risk factors for CVD in HD patients in the Han Chinese population.

Heterogeneous effect of two selectin gene polymorphisms on coronary artery disease risk: a meta-analysis

Background

The selectins play important roles in the inflammatory process of coronary artery disease (CAD) and myocardial infarction (MI). Previous studies have shown ambiguous findings regarding a possible association between the selectin genes and CAD. The E-selectin Ser128Arg polymorphism and the P-selectin Thr715Pro polymorphism have been investigated widely but with inconsistent results. We performed a comprehensive meta-analysis to shed light on this issue.

Methods

Data were extracted by searches of MEDLINE, Embase, CNKI, Wanfang, Google Scholar, PORTA, GeNii, CiNii, J-STAGE, Nurimedia and Koreanstudies Information Service System [Kiss] up to October 2013, in which 10 studies on the Ser128Arg polymorphism with 3369 cases and 2577 controls and 10 studies on the Thr715Pro polymorphism with 5886 cases and 18345 controls. A random-effects model was used to calculate the combined odds ratios. The between-study heterogeneity and publication bias were addressed.

Results

The 128Arg carriers had a significant increased risk of CAD (allele comparison: P = 0.02, OR = 1.33, 95%CI 1.04–1.69, P_{heterogeneity} = 0.01); The 715Pro conferred a non-significant risk reduction relative to the 715Thr (allele comparison: P = 0.40, OR = 0.94, 95%CI 0.82–1.08, P_{heterogeneity} = 0.03).Subgroup analyses demonstrated that the 128Arg carriers had a significant increased risk of CAD among Asians (allele comparison: P = 0.001, OR = 2.07, 95%CI 1.33–3.24, P_{heterogeneity} = 0.77) but not among Caucasians (allele comparison: P = 0.33, OR = 1.13, 95%CI 0.88–1.45, P_{heterogeneity} = 0.08). Carrier status for the 715Pro was significantly associated with reduced risk of MI (allele comparison: P = 0.04, OR =  0.81, 95%CI 0.67–0.99, P_{heterogeneity} = 0.14). The asymmetric funnel plot and the Egger's test (P = 0.041) suggested the presence of publication bias for the Ser128Arg polymorphism.

Conclusion

Our results suggested there is an increase in the risk of CAD conferred by the Ser128Arg polymorphism and the thr715Pro polymorphism may be a protective factor of MI.

The Connexin37 gene C1019T polymorphism and risk of coronary artery disease: a meta-analysis

BACKGROUND AND AIMS

Mounting data have emerged suggesting that the Connexin37 C1019T polymorphism increases susceptibility to coronary artery disease (CAD). However, previous studies yielded conflicting results. In the current study, a comprehensive meta-analysis was performed to investigate whether the C1019T polymorphism is associated with CAD risk.

METHODS

A total of 11 studies examining the C1019T polymorphism and CAD were identified using MEDLINE, Embase, CNKI, Wanfang and CBM, in which 5535 CAD patients and 5626 controls were analyzed. A random-effects model was used to calculate odd ratios and confidence intervals, while addressing between-study heterogeneity. Publication bias was weighed using the Egger's test, Begg-Mazemdar test and funnel plot.

RESULTS

In genetic models with striking heterogeneity, the risk of CAD was not associated with the C1019T polymorphism (allele comparison: p = 0.34, OR = 1.11, 95% CI 0.90-1.36). Stratification by disease endpoints indicated that the 1019T allele was significantly associated with myocardial infarction (MI) (allele comparison: p <0.001, OR = 1.59, 95% CI 1.24-2.03). Further meta-regression analysis indicated that a large proportion of heterogeneity was probably due to the varying proportions of diabetes mellitus (DM) across studies (p = 0.014).

CONCLUSIONS

Our results indicated that the C1019T polymorphism may be a moderate risk factor for MI and that DM was likely a potential source of between-study heterogeneity.

IRS1, TCF7L2, ADRB1, PPARG, and HHEX polymorphisms associated with atherogenic risk in Mexican population

Objective. We aimed to explore the association between polymorphisms of IRS1 (rs1801278), TCF7L2 (rs7903146 and rs12255372), ADRB1 (rs1801253), PPARG (rs1801282), and HHEX (rs5015480) genes with atherogenic risk (AI = Total cholesterol/HDL) in MetS, T2D, and healthy populations from the Mexican Social Security Institute. Methodology and Results. Four hundred thirty-five MetS, 517 T2D, and 547 healthy individuals were selected. The association between the SNPs and the atherogenic index was evaluated by multiple linear regression and multinomial logistic regression models. The ADRB1 gene showed a statistically significant association with high-risk atherogenic index, OR = 2.94 (IC 95% 1.64-5.24; P < 0.0001) for the Arg/Gly variant, under the dominant model an OR = 2.96 (IC 95% 1.67-5.25; P < 0.0001), and under the Log additive model an OR = 2.52 (IC 95% 1.54-4.15; P < 0.0001). Conclusions. The Arg389Gly polymorphism of the ADRB1 gene may be a worthy biological marker to predict the risk of developing cardiovascular diseases given a high-risk atherogenic index.

Relationship of the p22phox (CYBA) gene polymorphism C242T with risk of coronary artery disease: a meta-analysis

Background

Observational and experimental studies have thus far been unable to resolve whether the CYBA C242T polymorphism is associated with coronary artery disease (CAD). Therefore, we undertook a comprehensive meta-analysis to more precisely evaluate the influence of this polymorphism on CAD and potential biases.

Methods

We screened MEDLINE, Embase, CNKI, Wanfang and CBM up to January 2013 and extracted data from 22 studies with 9,279 CAD patients and 9,349 controls. A random-effects model was exploited to synthesize the inconsistent outcomes of the individual studies, while addressing between-study heterogeneity and publication bias.

Results

The CYBA C242T polymorphism conformed to Hard-Weinberg Equilibrium for all studies (P>0.05). Overall comparison of the T allele with the C allele produced a non-significant risk estimate for CAD but with striking heterogeneity (T versus C: P = 0.87, OR = 0.99, 95%CI 0.89–1.11, P_{heterogeneity}<0.0001, I² = 67.8%). However, subgroup analysis by ethnicity documented that the T allele carriers had a marginal risk increase (21%) of CAD among Caucasians (recessive genetic model: P = 0.05, 95%CI 1.00–1.46, P_{heterogeneity} = 0.15, I² = 29.1%). Then data were divided into study design, the significance of CAD risk increase was substantially strengthened in matched case-control studies (allele comparison: P = 0.02, OR = 1.13, 95%CI 1.02–1.26, P_{heterogeneity} = 0.24, I² = 21.6%).Further meta-regression analysis identified that a large proportion of heterogeneity was explained by body mass index (BMI) (P = 0.03, OR = 1.07, 95%CI 1.01–1.15) and study design (P = 0.03, OR = 1.30, 95%CI 1.02–1.64).There was no obvious publication bias as verified by funnel plot and Egger's linear regression test (t = −0.25, P = 0.81 for allele comparison).

Conclusion

Taken together, our results suggested the CYBA C242T polymorphism might be a risk-conferring factor on developing CAD and BMI and study design were probable sources of between-study heterogeneity.

Association of Pro12Ala (rs1801282) variant of PPAR gamma with rheumatoid arthritis in a Pakistani population

Peroxisome proliferator-activated receptor-gamma (PPAR-gamma) belongs to a receptor superfamily of ligand-activated transcription factors, encoded by PPARG gene. Role of PPARγ has been well established in variety of metabolic disorders and in regulation of inflammation. In the present study, we aimed to investigate the association of PPARG (Pro12Ala; rs1801282) in clinically definite Pakistani Rheumatoid Arthritis (RA) patients and matching controls. The genotypes of the Pro12Ala variant in the PPARG were determined in a sample of 300 Pakistanis, including 150 RA cases and 150 controls. The genotyping was performed using Amplification Refractory Mutation System-Polymerase Chain Reaction (ARMS-PCR) method, and the data was analyzed through Graphpad Prism 5 V software. Allele-specific primer set (two forward: PPARG-F1, PPARG-F2 and a common reverse primer: PPARG-R) was used for amplification, and the product was resolved on 2 % agarose gel. The CC (ProPro) genotype has higher frequency in controls than RA cases [75 (50.0 %) vs. 51 (34.0 %)], whereas the CG (ProAla) genotype has relatively same frequencies in both cases and controls [72 (48.0 %) vs. 70 (46.6 %)]. However, significantly higher frequency of GG (AlaAla) genotype was observed in cases [27 (18.0 %) vs. 5 (3.3 %); χ2 18.54; p < 0.0001]. Furthermore, the minor allele G has significantly higher allele frequency in cases having same trend and direction of association (OR 1.991(1.412-2.808); p < 0.0001). These observations suggest that Pro12Ala (rs1801282), a coding variant in the PPARG gene, is associated with Rheumatoid Arthritis in Pakistanis.