Association of Renalase SNPs rs2296545 and rs2576178 with the Risk of Hypertension: A Meta-Analysis

The prevalence and odds of bipolar disorder in women with polycystic ovary syndrome (PCO) disease: a systematic review and meta-analysis

BACKGROUND

Women with polycystic ovary syndrome (PCO) suffer from psychological difficulties like bipolar disorder. Various studies in the literature report several prevalence rates of bipolar disorder in women with PCO, while there is no systematic review in this field. So, we designed this systematic review and meta-analysis to estimate the pooled prevalence and odds of bipolar disorder in women with PCO disease.

METHOD

PubMed, Scopus, EMBASE, Web of Science, Google Scholar, and references of the references, conference abstracts were comprehensively searched by two independent researchers. The search was done on May 1st, 2023.

RESULTS

A literature search revealed 438 records, 35 full texts were evaluated, and finally, 11 studies remained for systematic review. Totally, 73,102 women with PCO and 340,724 controls were evaluated. Among cases, 1471 had bipolar diagnosis vs. 4321 controls. The prevalence of bipolar disorder in women with PCO ranged between 0 and 27%, and the pooled prevalence was estimated as 4% (95% CI, 2-5%; I2, 99.3%, p < 0.001). The odds of bipolar disorder in women with PCO ranged between 0.98 and 8.78, and the pooled estimate was 2.06 (95% CI, 1.61-2.63) (I2, 85.6%; p < 0.001).

CONCLUSIONS

This systematic review and meta-analysis show that the pooled prevalence of bipolar disorder in women with PCO is 4%, and women with PCO are at a 2-fold higher risk of bipolar disorder.

Association Between Renalase Gene Polymorphism (rs2296545) and Hypertension in Egyptian Chronic Kidney Disease Patients

Background Renalase gene polymorphisms are associated with an increased risk of essential hypertension, chronic kidney disease (CKD), heart disease, diabetes, and stroke. One of these polymorphisms is a common missense (rs2296545) polymorphism, which was reported to be related to hypertension. The aim of this work was to investigate the possible relation between renalase gene polymorphism (rs2296545) and hypertension in patients with CKD patients. Subjects and methods Ninety patients were included in this case-control study: 30 normotensive CKD patients, 30 hypertensive CKD patients, and 30 apparently healthy controls. Genomic deoxyribonucleic acid (DNA) was extracted from peripheral whole blood, and renalase gene (rs2296545) polymorphism was genotyped in all patients and controls by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Odds ratios (OR) and their 95% CIs were calculated. Results We found that the CC genotype and the C allele renalase (rs2296545) were statistically associated with the risk of CKD (OR= 9.4; 95%CI 1.2-7.2; P= 0.036) and (OR= 3.78; 95%CI 1.57-9.08; P= 0.003), respectively. There was a statistically significant difference between the hypertensive CKD patients and the controls regarding the CC genotypes and the C allele, (26.7% versus 3.3%, P= 0.018) and (40% versus 11.7%, P< 0.001) for the CC genotype and the C allele, respectively. The mean values of systolic and diastolic blood pressure were higher in the normotensive CKD patients with the CC genotype compared to other genotypes (P= 0.014 and P= 0.022, respectively) and also were higher in hypertensive CKD patients with the CC genotype when compared to other genotypes (P= 0.001 for both). Conclusion This study demonstrated a statistically significant increase in the renalase gene (rs2296545) CC genotype and the C allele in CKD patients, especially hypertensive CKD.

Molecular Role of Asn680Ser and Asp37Glu Missense Variants in Saudi Women with Female Infertility and Polycystic Ovarian Syndrome

Female infertility (FI) is a global health issue. Polycystic ovary syndrome (PCOS) is a common cause of FI. The renalase gene (RNLS) is associated with FI and other human diseases. Based on the documented missense variants, rs6166 and rs2296545 single-nucleotide polymorphisms (SNPs) were not identified in Saudi women with FI and PCOS. This study aimed to investigate the molecular role of the two SNPs in Saudi women with FI and PCOS. In this cross-sectional study, 96 healthy controls, 96 women with FI, and 96 women with PCOS were recruited. DNA was isolated, and polymerase chain reactions and Sanger sequencing analysis were performed using rs6166 and rs2296545 SNPs. The data obtained from the three groups were used to perform statistical analyses based on genotype, allele frequencies, regression models, and ANOVA analysis. Both rs6166 and rs2296545 had no role in FI or PCOS in Saudi women. A predicted reason for non-association in Saudi women could be the role of elderly women in the controls compared with women with FI and PCOS. Moreover, age, weight, and body mass index were higher in the control group than the FI and PCOS groups. In conclusion, rs6166 and rs2296545 SNPs were not associated with FI or PCOS in Saudi women.

A candidate locus in the renalase gene and susceptibility to blood pressure responses to the dietary salt

BACKGROUND

High dietary salt confers a risk of elevating blood pressure (BP) and the development of hypertension. BP to salt intake may be determined in part by individual genetic predisposition. Identifying these genetic underpinnings will enhance our understanding of the biological mechanisms of BP regulation. This study aims to assess the genetic association with salt sensitivity of BP (SSBP) within two well-phenotyped multinational cohorts.

METHODS

A total of 720 white participants from the HyperPATH consortium program were selected and genotyped using a multiethnic genotyping array. Individuals consumed two study diets containing high (>200 mEq/day) and low (<10 mEq/day) sodium content, after which SSBP, aldosterone, and plasma renin activity (PRA) were assessed in a controlled inpatient research setting.

RESULTS

A top signal (rs10887801; beta = 4.57, P  = 5.03E - 07) at the renalase gene ( RNLS ) region was significantly associated with SSBP. We also identified seven single nucleotide variants with linkage disequilibrium to the top signal at this region that comprised a significant haplotype (TCTTAGTT, P  = 0.00081). Homozygous carriers of the T-risk allele of the key single nucleotide variant had higher SSBP ( P  ≤ 0.00001) and lower PRA ( P  = 0.0076) compared with the nonrisk allele.

CONCLUSION

We identified significant associations between genetic variants of the RNLS gene and BP responses to dietary salt intervention and PRA that suggest susceptibility to volume-driven hypertension. These findings may contribute to a better understanding of the genetic mechanisms underlying BP regulation, support the role of RNLS in the pathogenesis of SSBP, and identify individuals who may be at risk from excess dietary salt intake.

Pregnancy History, Oral Contraceptive Pills Consumption (OCPs), and Risk of Multiple Sclerosis: A Systematic Review and Meta-Analysis

Background

To estimate the pooled odds of oral contraceptive pills consumption (OCPs) use as well as pregnancy history and multiple sclerosis (MS) risk.

Methods

We systematically searched PubMed, Embase, Scopus, Web of Science, Google scholar, and gray literature including references of the references as well as conference papers. The search strategy in PubMed was ((Oral contraceptive pills) OR OCP) AND (Multiple Sclerosis OR Sclerosis, Multiple) OR Sclerosis, Disseminated) OR Disseminated Sclerosis) OR MS (Multiple Sclerosis)) OR Multiple Sclerosis, Acute Fulminating) AND (gravidity) OR (pregnancy).

Results

Four studies were included. The pooled odds of developing MS in women with pregnancy history compared with nulligravid women was 0.64 (95%CI = 0.53 - 0.78) (I ² = 0, P = 0.5), which means that pregnancy reduces the risk of MS by 36%. The pooled odds of OCP consumption and risk of MS were 1.09 (95% CI = 0.67 - 1.76). By comparing the pooled odds of OCP consumption and risk of MS according to the country of the origin, we found that the pooled odds in Iranian studies was 1.03 (95% CI = 0.31 - 3.45) and the pooled OR in studies that were conducted in the United States was 1.13 (95% CI = 0.65 - 1.98), which showed that the country of the origin was not the cause of heterogeneity.

Conclusions

The results of this systematic review show that pregnancy history is a protective factor for MS development, whereas OCP use has no significant effect.

Deletion of the RNLS Gene using CRISPR/Cas9 as Pancreatic Cell β Protection against Autoimmune and ER Stress for Type 1 Diabetes Mellitus

BACKGROUND: Type 1 diabetes mellitus (T1DM) is a chronic disease in children which is usually caused by autoimmunity that damages pancreatic a and b cells which have functions as blood glucose regulators. Some studies stated that Renalase (RNLS) gene deletion will protect these b cells from autoimmune reactions and Endoplasmic Reticulum (ER) stress. RNLS deletion by genome editing Clustered Regular interspersed Short Palindromic Repeats-CRISPR-related (CRISPR/Cas9) is believed to have the potential to be a therapy for T1DM Patients. AIM: This research was conducted to know the potential of RNLS deletion using the CRISPR/Cas9 as an effective therapy and whether it has a permanent effect on T1DM patients. METHODS: The method applied in this research summarized articles by analyzing the titles and abstracts of various predetermined keywords. In this case, the author chose a full-text article published within the past 10 years by prioritizing searches in the last 5 years through PubMed, Google Scholar, Science Direct, Cochrane, American Diabetes Association, and official guidelines from IDAI. RESULTS: RNLS deletion using CRISPR/Cas9 in mice weakened the response of polyclonal -cell-reactive CD8+ T cells and disrupted the immune recognition to cells so that autoimmune killing did occur. In addition, such deletion prevents RNLS ER stress by increasing the threshold, triggering the unfolded protein response so that ER stress is difficult to occur. RNLS mutations in b cells also increase b cell survivability to oxidative stress. CONCLUSION: b cells RNLS deletion by genome editing CRISPR/Cas9 is effective in protecting b cells from autoimmune reactions and RE stress. However, further research is needed to determine the side effects and safety of its use.

The Effect of Renalase rs2576178 and rs10887800 Polymorphisms on Ischemic Stroke Susceptibility in Young Patients (<50 Years): A Case-Control Study and In Silico Analysis

Background

Ischemic stroke (IS) is the most common form of cerebrovascular accident which its precise etiology remains mysterious. Renalase is a catecholamine-degrading enzyme playing a major role in blood pressure control. Recent studies show the effect of renalase activity on various diseases like IS. In the current study, we examined the possible effects of renalase gene (RNLS) rs2576178 and rs10887800 variants at the 5′-flanking and intron 6 regions on IS, respectively.

Methods

One hundred and fifty-four IS patients younger than 50 years and 165 age- and sex-matched controls were recruited in the study. For genotyping of rs2576178 and rs10887800 variants, the PCR-RFLP method was used.

Results

The RNLS rs10887800 AG genotype was more repeated in IS patients, but the difference was marginally nonsignificant (P = 0.054). This variant was associated with IS in the overdominant model, and the AG genotype is associated with a1.6-fold increased risk of IS compared to AA+ GG genotypes (OR = 1.6, 95% CI: 1-2.5, P = 0.033). No relationship was observed between RNLS rs2576178 polymorphism and IS in all genetic models. The findings of the haplotype and combination effects of rs10887800 and rs2576178 variants on IS showed no significant association. The in silico analysis showed no effect of rs2576178 and rs10887800 polymorphisms in the RNA structure, but the alteration of RNA sequence in rs2576178 results in the lack of a MBNL1 protein binding site.

Conclusions

RNLS rs10887800 but not rs2576178 polymorphism was associated with IS susceptibility in the overdominant model (AG vs AA+ GG genotypes).

Renalase-A new understanding of its enzymatic and non-enzymatic activity and its implications for future research

Renalase was first described in 2005 and since then it became an object of scientific interest because of its proposed ability to catalyse circulating neurotransmitters and its promising antihypertensive effects. However, further research on the enzymatic activity of renalase did not confirm these initial findings and yielded that renalase serves to oxidize isomeric forms of β-NAD(P)H and recycle them by forming β-NAD(P)+. Moreover, in contrast to initial assumptions, it is indicated that renalase's enzymatic activity is confined to the cell and that extracellular renalase loses its enzymatic properties. These new reports led scientists to question as to whether renalase, as an enzyme, still has the potential to influence various systemic physiological responses (e.g. blood pressure). It was also put into question whether many physiological discoveries published based on the notion that renalase is secreted into the blood and acts by oxidation of catecholamines can still be considered valid. In this article, we attempt to review the literature to confront these doubts and find further possible directions of research on the importance of renalase. Our aim was to evaluate recent reports of non-enzymatic activity for renalase.

Association of renalase gene polymorphisms with the risk of hypertensive disorders of pregnancy in northeastern Han Chinese population

Renalase is a novel enzyme that can regulate blood pressure by degrading circulating catecholamines. We aimed to evaluate the possible effect of rs2296545, rs2576178 and rs10887800 polymorphisms of the renalase gene (RNLS) on the development of hypertensive disorders of pregnancy (HDP). This case-control study consisted of 185 patients with HDP and 380 normotensive pregnant women from the northeastern Chinese Han population. Association analyses were performed using PLINK, to compare allele and genotype frequencies in cases and controls. Adjustment for logistic regression analysis was performed by permutation testing. In the HDP patients compared with controls, we found that there was statistically significant difference in genotype distribution of rs2296545 (p = .037). Rs2296545 and rs2576178 polymorphisms have 1.91-fold (p = .004) and 1.73-fold (p = .015) increased risk of HDP in the dominant model, respectively. When compared preeclampsia (PE) to control, the RNLS rs2296545 polymorphism was significantly associated with PE risk in the dominant model (p = .021). We next analyzed the haplotypes of these SNPs and there was no difference between controls and HDP or PE. These findings suggest that rs2296545 was significantly associated with HDP and PE risk and the rs2576178 polymorphism may increase the susceptibility to HDP.

Roles and mechanisms of renalase in cardiovascular disease: A promising therapeutic target

Cardiovascular disease (CVD) is prevalent worldwide and remains a leading cause of death. Although substantial progress has been made in the diagnosis and treatment of CVD, the prognosis remains unsatisfactory. Renalase is a newly discovered cytokine that is synthesized by the kidney and then secreted into blood. Numerous studies have suggested the efficacy of renalase in treating CVD by metabolizing catecholamines in the circulatory system. As a new biomarker of heart disease, renalase is normally recognized as a signalling molecule that activates cytoprotective intracellular signals to lower blood pressure, protect ischaemic heart muscle and promote atherosclerotic plaque stability in CVD, which subsequently improves cardiac function. Due to its important regulatory role in the circulatory system, renalase has gradually become a potential target in the treatment of CVD. This review summarizes the structure, mechanism and function of renalase in CVD, thereby providing preclinical evidence for alternative approaches and new prospects in the development of renalase-related drugs against CVD.

Renalase and hypertension-demographic and clinical correlates in obstructive sleep apnea

BACKGROUND

Renalase plays an important role in blood pressure regulation. Obstructive sleep apnea (OSA) is a common respiratory disorder associated with hypertension and cardiovascular complications. The aim of the study was to assess the relationship between sleep apnea and renalase concentration.

MATERIAL AND METHODS

Adult patients (n = 113) were evaluated for OSA in a sleep laboratory using polysomnography. The respiratory events were scored according to the standards developed by the American Academy of Sleep Medicine. The blood renalase concentration was determined by the ELISA (enzyme-linked immunosorbent assay) test.

RESULTS

OSA (AHI ≥ 5) was diagnosed in 71% (n = 80) of the studied population. Renalase concentration was statistically significantly lower in the group with moderate-to-severe OSA (AHI ≥ 15) compared with the group without OSA (AHI < 5) (139.56 ± 175.72 ng/ml vs. 230.97 ± 240.50 ng/ml, p = 0.042). We have found statistically significant negative correlation between renalase and AHI in hypertensives, but not in normotensives. The statistically significant negative correlation was observed between AHI and renalase in the whole studied group, in males, and in the group of age < 60 years old. There was not such a correlation in females and in the group > 60 years old. Based on the regression model, it was shown that lower renalase concentration, hypertension, higher BMI, and male gender are independently associated with higher AHI.

CONCLUSIONS

There is a relationship between the blood renalase concentration and the severity of OSA, which may influence hypertension development in OSA.

Age at menarche and risk of multiple sclerosis (MS): a systematic review and meta-analysis

BACKGROUND

Some studies have looked at the age at menarche and risk of Multiple Sclerosis (MS).We aimed to conduct a systematic review and meta-analysis to estimate a pooled odds ratio of developing MS by increasing age at menarche.

METHODS

We searched PubMed, Scopus, EMBASE, CINAHL, Web of Science, Ovid, google scholar and gray literature (references of references, congress abstracts) up to 10th April 2019.

RESULTS

The literature search found 312 articles. After eliminating duplicates, reviews, case reports and trials, 18 articles remained. Three articles were ultimately included in the final analysis. Two studies were from Iran, and one from Canada. The pooled odds ratio (OR) for increasing 1 year of age at menarche was 0.88 (95% CI:0.82-0.94), with no significant heterogeneity (I2 = 49%, p = 0.1). Mean age at menarche was significantly different between case and control groups (mean difference = - 0.22, 95% CI = -0.42,-0.02).

CONCLUSION

The result of this systematic review showed that the risk of MS decreases by increasing age at menarche.

Association of Plasma Renalase and Left Ventricle Mass Index in Heart Failure Patients Stratified to the Category of the Ejection Fraction: A Pilot Study

Heart failure represents a growing health problem, with increasing morbidity and mortality globally. According to the mechanisms involved in the pathogenesis of heart failure, many biomarkers have been proposed for the timely diagnosis and prognostication of patients with heart failure, but other than natriuretic peptides, none of them has gained enough clinical significance. Renalase, a new protein derived from kidneys was demonstrated to metabolize catecholamines and to have a cardioprotective role. The aim of the study was to determine whether renalase and brain natriuretic peptide (BNP) concentration could be used to differentiate heart failure patients stratified to the category of the ejection fraction and whether plasma renalase could be used as a biomarker for left ventricle hypertrophy in all subgroups of heart failure patients. We included patients diagnosed with heart failure and stratified them to the three subgroups according to the ejection fraction. Regarding echocardiographic parameters, HFmrEF had an intermediate profile in between HFrEF and HFpEF, with statistical significance in most evaluated parameters. BNP concentration was significantly different in all three subgroups (p < 0.001), and renalase was statistically higher in HFrEF (p = 0.007) compared to the HFmrEF and HFpEF, where its results were similar, without statistical significance. Renalase plasma concentration was demonstrated to be highly and positively associated with left ventricle mass index in HFrEF (p = 0.029), as well as increased plasma concentration of BNP (p = 0.006). In the HFmrEF group of patients, body mass index was positively associated with LVMI (p = 0.05), while in the patients with HFpEF, diabetes mellitus was demonstrated to have a positive association with LVMI (p = 0.043). These findings suggest that renalase concentration may be measured in order to differentiate patients with reduced ejection fraction. Plasma renalase concentrations positively correlated with left ventricle hypertrophy in patients with reduced ejection fraction, being strongly associated with increased left ventricular mass index.

Single nucleotide polymorphisms in Renalase and KCNQ1 genes and female infertility: A cross-sectional study in Pakistan

A global increase in the incidence of subfertility is observed, and research suggests strong genetic influences that might restrict fertility directly or indirectly. It therefore becomes important to rule out the existence of genetic causes and counsel infertile couples before offering "Advanced Infertility Treatment Techniques." This cross-sectional study aimed to explore the association of KCNQ1 (rs2237895) and Renalase (rs2576178 and rs10887800) single nucleotide polymorphisms with different causes of infertility by analysing 508 fertile and 164 infertile women. Gene variant (AC/CC) of KCNQ1 rs2237895 showed a slight difference in the endometriosis group compared to the fertile group (p = .049), with the C allele showing a significant association with infertility overall (OR = 1.42 [1.100-1.833]; p < .0069). The variant AG/GG of Renalase rs2576178 was significantly associated with overall infertility (OR = 2.266; p < .001), with a strong G allele association with unexplained infertility OR = 2.796 (p = .002) that remained significant after adjusting for age and body mass index. Similarly, Renalase rs10887800 AG/GG and G allele showed significant association with both infertility due to polycystic ovarian syndrome and unexplained infertility. Expression of single nucleotide polymorphism rs2237895 and rs2576178 in both KCNQ1 and Renalase genes might be responsible for altering reproductive potential, hence leading to infertility in women.

The association of toll-like receptor 4 gene polymorphisms with primary open angle glaucoma susceptibility: a meta-analysis

Primary open angle glaucoma (POAG) and normal tension glaucoma (NTG) cause irreversible blindness while current medications cannot completely inhibit disease progression. An understanding of immunopathogenesis is thus a keystone to develop novel drug targets and genetic markers are still required for early diagnosis. Toll-like receptor 4 (TLR4) is an essential player in inflammation in various diseases. However, the TLR4 polymorphisms have not been completely elucidated in both types of glaucoma. The aim of the present study was to identify the association between TLR4 polymorphism and glaucoma (POAG and NTG) via the use of a comprehensive review and meta-analysis. The relevant studies were collected from PubMed, Excerpta Medica Database (EMBASE), and Web of Science to identify eight included articles, assessed for quality by a modified Newcastle-Ottawa Scale (NOS) for gene association study. A meta-analysis was applied to calculate the pooled odds-ratio and 95% confidence intervals (CIs) to evaluate the association between TLR4 polymorphism and glaucoma. The results revealed that TLR4 rs1927911 A/G, rs12377632 C/T, and rs2149356 G/T significantly decrease the risk of POAG and NTG in allele contrast models 0.71-, 0.71-, and 0.67-fold, respectively. Moreover, rs4986790 A/G and rs4986791 C/T showed a stringent association with POAG in allele contrast, heterozygous, recessive, and overdominant models. In conclusion, this meta-analysis represented a significant correlation between TLR4 polymorphisms and both types of glaucoma suggesting that TLR4 might be involved in the pathogenesis of glaucoma and may be applied as a genetic marker for disease screening.

The associations between Toll-like receptor 4 gene polymorphisms and hepatitis C virus infection: a systematic review and meta-analysis

Background and objective: The hepatitis C virus (HCV) is able to cause a life-threatening disease relating to lethal hepatocellular carcinoma. Previous, Toll-like receptor polymorphisms were proposed as promising biomarker for HCV-related hepatocellular carcinoma and disease progression. This study aimed to summarize the association of TLR4 polymorphisms and HCV infection through meta-analysis.

Methods: We applied a systematic review and meta-analysis performed by using PubMed, EMBASE and Web of Science searches. The Modified Newcastle-Ottawa scale was used for quality assessment. The odd-ratio (OR) and 95% confidence interval (CI) were calculated to assess the association. In silico analysis was applied for proposing the function as microRNA (miRNA) of non-coding polymorphism. Finally, the miRNA target was predicted and annotated to suggest the possible relationship between polymorphism and HCV infection.

Results: Our meta-analysis incorporated seven studies involving rs4986791, rs4986790 and rs2149356. No association exists between rs4986791 and HCV infection. However, the heterozygous model (AG vs GG) of rs4986790 significantly associates with HCV infection (OR = 0.33, 95% CI = 0.21–0.49, P<0.0001). Moreover, the rs2149356 TG genotype also associates with HCV infection in the over-dominant model (TG vs TT+TG: OR = 0.54, 95% CI = 0.40–0.75). In silico analysis of rs2149356G allele showed that this mutation is siRNA, which targets the set of genes, especially in the autophagy pathway.

Conclusion: We demonstrated that rs4986790 and rs2149356 are associated with HCV infection.

Genome-Wide Association Study of Circadian Rhythmicity in 71,500 UK Biobank Participants and Polygenic Association with Mood Instability

BACKGROUND

Circadian rhythms are fundamental to health and are particularly important for mental wellbeing. Disrupted rhythms of rest and activity are recognised as risk factors for major depressive disorder and bipolar disorder.

METHODS

We conducted a genome-wide association study (GWAS) of low relative amplitude (RA), an objective measure of rest-activity cycles derived from the accelerometer data of 71,500 UK Biobank participants. Polygenic risk scores (PRS) for low RA were used to investigate potential associations with psychiatric phenotypes.

OUTCOMES

Two independent genetic loci were associated with low RA, within genomic regions for Neurofascin (NFASC) and Solute Carrier Family 25 Member 17 (SLC25A17). A secondary GWAS of RA as a continuous measure identified a locus within Meis Homeobox 1 (MEIS1). There were no significant genetic correlations between low RA and any of the psychiatric phenotypes assessed. However, PRS for low RA was significantly associated with mood instability across multiple PRS thresholds (at PRS threshold 0·05: OR = 1·02, 95% CI = 1·01-1·02, p = 9·6 × 10-5), and with major depressive disorder (at PRS threshold 0·1: OR = 1·03, 95% CI = 1·01-1·05, p = 0·025) and neuroticism (at PRS threshold 0·5: Beta = 0·02, 95% CI = 0·007-0·04, p = 0·021).

INTERPRETATION

Overall, our findings contribute new knowledge on the complex genetic architecture of circadian rhythmicity and suggest a putative biological link between disrupted circadian function and mood disorder phenotypes, particularly mood instability, but also major depressive disorder and neuroticism.

FUNDING

Medical Research Council (MR/K501335/1).

Association of Interleukin-1 gene clusters polymorphisms with primary open-angle glaucoma: a meta-analysis

Background

Previous studies have associated the Interleukin-1 (IL-1) gene clusters polymorphisms with the risk of primary open-angle glaucoma (POAG). However, the results were not consistent. Here, we performed a meta-analysis to evaluate the role of IL-1 gene clusters polymorphisms in POAG susceptibility.

Methods

PubMed, EMBASE and Cochrane Library (up to July 15, 2017) were searched by two independent investigators. All case-control studies investigating the association between single-nucleotide polymorphisms (SNPs) of IL-1 gene clusters and POAG risk were included. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated for quantifying the strength of association that has been involved in at least two studies.

Results

Five studies on IL-1β rs16944 (c. -511C > T) (1053 cases and 986 controls), 4 studies on IL-1α rs1800587 (c. -889C > T) (822 cases and 714 controls), and 4 studies on IL-1β rs1143634 (c. +3953C > T) (798 cases and 730 controls) were included. The results suggest that all three SNPs were not associated with POAG risk. Stratification analyses indicated that the rs1143634 has a suggestive associated with high tension glaucoma (HTG) under dominant (P = 0.03), heterozygote (P = 0.04) and allelic models (P = 0.02), however, the weak association was nullified after Bonferroni adjustments for multiple tests.

Conclusions

Based on current meta-analysis, we indicated that there is lack of association between the three SNPs of IL-1 and POAG. However, this conclusion should be interpreted with caution and further well designed studies with large sample-size are required to validate the conclusion as low statistical powers.

Electronic supplementary material

The online version of this article (doi: 10.1186/s12886-017-0616-y) contains supplementary material, which is available to authorized users.

Functional polymorphism of the renalase gene is associated with cardiac hypertrophy in female patients with aortic stenosis

Renalase decreases circulating catecholamines concentration and is important in maintaining primary cellular metabolism. Renalase acts through the plasma membrane calcium ATPase 4b in the heart, which affects pressure overload but not exercise induced heart hypertrophy. The aim of this study was to test the association between a functional polymorphism Glu37Asp (rs2296545) of the renalase gene and left ventricular hypertrophy in a large cohort of patients with aortic stenosis. The study group consisted of 657 patients with aortic stenosis referred for aortic valve replacement. Preoperative echocardiographic assessment was performed to obtain cardiac phenotypes. Generalized-linear models were implemented to analyze data using crude or full model adjusted for selected clinical factors. In females, the Asp37 variant of the Glu37Asp polymorphism was associated with higher left ventricular mass (p = 0.0021 and p = 0.055 crude and full model respectively), intraventricular septal thickness (p = 0.0003 and p = 0.0143) and posterior wall thickness (p = 0.0005 and p = 0.0219) all indexed to body surface area, as well as relative wall thickness (p = 0.001 and p = 0.0097). No significant associations were found among the male patients. In conclusion, we have found the association of the renalase Glu37Asp polymorphism with left ventricle hypertrophy in large group of females with aortic stenosis. The Glu37Asp polymorphism causes not only amino-acid substitution in FAD binding domain but may also change binding affinity of the hypoxia- and hypertrophy-related transcription factors and influence renalase gene expression. Our data suggest that renalase might play a role in hypertrophic response to pressure overload, but the exact mechanism requires further investigation.

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.

Extracellular renalase protects cells and organs by outside-in signalling

Renalase was discovered as a protein synthesized by the kidney and secreted in blood where it circulates at a concentration of approximately 3-5 μg/ml. Initial reports suggested that it functioned as an NAD(P)H oxidase and could oxidize catecholamines. Administration of renalase lowers blood pressure and heart rate and also protects cells and organs against ischaemic and toxic injury. Although renalase's protective effect was initially ascribed to its oxidase properties, a paradigm shift in our understanding of the cellular actions of renalase is underway. We now understand that, independent of its enzymatic properties, renalase functions as a cytokine that provides protection to cells, tissues and organs by interacting with its receptor to activate protein kinase B, JAK/STAT, and the mitogen-activated protein kinase pathways. In addition, recent studies suggest that dysregulated renalase signalling may promote survival of several tumour cells due to its capacity to augment expression of growth-related genes. In this review, we focus on the cytoprotective actions of renalase and its capacity to sustain cancer cell growth and also the translational opportunities these findings represent for the development of novel therapeutic strategies for organ injury and cancer.

Age influence on renalase and catecholamines concentration in hypertensive patients, including maintained dialysis

BACKGROUND

Hypertension in elderly patients is one of the main problems in cardiovascular diseases. The sympathetic nervous system hyperactivity seen in older patients is a known risk factor for hypertension and other cardiovascular events as well as chronic kidney disease. Renalase, secreted by the kidney and circulated in blood, may regulate the sympathetic tone by catecholamine degradation and in this way has an impact on cardiovascular and renal complications.

OBJECTIVE

To assess the impact of age on renalase and catecholamine concentration in hypertensive patients, including those on dialyses and its possible relation to blood pressure control and cardiovascular disease.

METHODS

The study cohort of 211 patients was divided into two groups according to age below 65 years (range 19-64) and above 65 years (range 65-86). The older group represented 38% of the whole studied population and 75% of them were dialyzed. The two groups of different ages were also divided into dialysis and nondialysis subgroups. The serum renalase, dopamine, and norepinephrine concentration together with blood pressure value and echocardiography were assessed.

RESULTS

Patients aged 65 years and more had higher renalase (20.59 vs 13.14 µg/mL, P=0.02) and dopamine (41.71 vs 15.46 pg/mL, P<0.001) concentration as well as lower diastolic blood pressure (75.33 vs 85 mmHg, P=0.001), advanced abnormalities in echocardiography, and more often suffered from diabetes and coronary artery disease. The significant correlation between age and renalase (r=0.16; P=0.019), norepinephrine (r=0.179; P=0.013), and dopamine (r=0.21; P=0.003) was found in the whole study population. In the nondialysis subgroup, 44% had chronic kidney disease, mostly in the stage 2 (83%). There was a significantly higher norepinephrine concentration (1.21 vs 0.87 ng/mL; P=0.008) in older patients of that population. In the dialysis subgroup, there were no differences between renalase and catecholamine level but older participants had lower diastolic blood pressure (69 vs 78 mmHg, P=0.001) and ejection fraction (51% vs 56.8%, P=0.03).

CONCLUSION

The elevated renalase level in older hypertensive patients is related rather to kidney function and cardiovascular diseases than to age itself. Thus, renalase appears to be the possible new marker of these indications in this special population.