Apolipoprotein A5 polymorphisms in Turkish population: association with serum lipid profile and risk of ischemic stroke

A novel prognosis prediction model, including cytotoxic T lymphocyte-associated antigen-4, ischemia-modified albumin, lipoprotein-associated phospholipase A2, glial fibrillary acidic protein, and homocysteine, for ischemic stroke in the Chinese hypertensive population

Background

There is still a lack of tools to assess the prognosis of ischemic stroke patients induced by hypertension. In this study, we built a novel prognostic assessment model for ischemic stroke in the Chinese hypertensive population.

Methods

Mass spectrometry technique was used to analyze the changes in serum protein profiles of hypertensive patients with ischemic stroke. A total of 314 hypertensive patients were divided into the testing group (206 patients) and the validation group (108 patients).

Results

Compared with hypertensive patients without ischemic stroke, serum cytotoxic T lymphocyte‐associated antigen‐4 (CTLA‐4), ischemia‐modified albumin (IMA), lipoprotein‐associated phospholipase A2 (Lp‐PLA2), glial fibrillary acidic protein (GFAP), and homocysteine (HCY) levels were significantly increased among hypertensive patients with ischemic stroke (p < 0.05). Then, we built a novel prognostic assessment model for hypertensive patients with ischemic stroke [Logit(P) = 29.172–1.088*CTLA‐4–0.952*IMA‐0.537*Lp‐PLA2 −0.066*GFAP −0.149*HCY]. It showed higher efficiency (AUC = 0.981, sensitivity = 95.5%, specificity = 93.8%) than any single marker. The estimated probability was 0.739, which means if higher than 0.739, it was classified into poor prognosis. Compared with the estimated probability ≤0.739 group, the survival rate of hypertensive patients with ischemic stroke in the estimated probability >0.739 group was significantly decreased (χ² = 40.001, p < 0.001). In the validation group, our novel prognostic assessment model still showed good efficiency (AUC = 0.969, sensitivity = 89.4%, specificity = 92.5%; χ² = 47.551, p < 0.001).

Conclusion

Current novel prognostic assessment model we have built is of great value in the prognostic evaluation for ischemic stroke in the Chinese hypertensive population.

Association of rs662799 variant and APOA5 gene haplotypes with metabolic syndrome and its components: a meta-analysis in North Africa

Apolipoprotein A5 (APOA5) has been linked to metabolic syndrome (MetS) in several populations. In North Africa, only the Tunisian and Moroccan populations were investigated. Our aim is to assess the association between APOA5 gene variant (rs662799) and haplotypes with MetS in Tunisian population and to perform a meta-analysis in North Africa. A total of 594 Tunisian participants were genotyped for polymorphism rs662799 using KASPar technology. Two polymorphisms rs3135506 and rs651821 in APOA5 gene genotyped in our previous study, were used in addition to rs662799 to assess the haplotype association with MetS. The genotype of 875 participants was used for the meta-analysis. Statistical analyses were performed with R software.

The rs662799 increases the risk of MetS under the dominant (P=0.018) and the additive models (P=0.028) in the Tunisian population. After stratification of the cohort following the sex and the geographic origin, a positive association of rs662799 with MetS was found for participant from the Northern region and for the women group. Only the haplotype AGT showed a significant association with MetS by decreasing the risk of the disease.

The meta-analysis reported a significant association of rs662799 and rs3135506 with MetS.

Our results showed a significant association between the APOA5 gene variants rs662799 and haplotypes with MetS and its traits in Tunisia. An impact of the sex and the geographic origin on the genotype distribution was highlighted. Our funding emphasizes the role of APOA5 in the development of MetS in North Africa.

Association of c.56C > G (rs3135506) Apolipoprotein A5 Gene Polymorphism with Coronary Artery Disease in Moroccan Subjects: A Case-Control Study and an Updated Meta-Analysis

PURPOSE

Coronary artery diseases (CAD) are clinical cardiovascular events associated with dyslipidemia in common. The interaction between environmental and genetic factors can be responsible for CAD. The present paper aimed to examine the association between c.56C > G (rs3135506) APOA5 gene polymorphism and CAD in Moroccan individuals and to perform an association update meta-analysis.

MATERIALS AND METHODS

The c.56C > G variant was genotyped in 122 patients with CAD and 134 unrelated controls. Genetic association analysis and comparison of biochemical parameters were performed using R statistical language. In addition, a comprehensive meta-analysis including eleven published studies in addition to our case-control study results was conducted using Review Manager 5.3. Publication bias was examined by Egger's test and funnel plot.

RESULTS

The case-control study data showed that the c.56C > G polymorphism was associated with CAD susceptibility under codominant (P-value = 0.001), recessive (P-value <0.001) and log-additive (P-value = 0.008) inheritance models. In addition, this polymorphism was significantly associated with increased levels of systolic and diastolic blood pressures, triglycerides, glycemia, and total cholesterol. Furthermore, meta-analysis showed a significant association between the c.56C > G gene polymorphism and increased risk of CAD under recessive (OR = 3.39[1.77-6.50], P value <0.001) and homozygote codominant (OR = 3.96[2.44-6.45], P value <0.001) models.

CONCLUSION

Our case-control study revealed a significant association between c.56C > G polymorphism and CAD in the Moroccan population. In addition, meta-analysis data supported the implication of this polymorphism in CAD susceptibility.

Cardio-metabolic risk factors in Tunisia: state of the art

Cardiometabolic risk factors in Tunisia are growing fast. The main risk factor is metabolic syndrome which is a global health issue in both developing and developed countries. It is resulting from a new phase of epidemiological transition characterised by ageing and an increase in non-communicable diseases. It is common in both genders with some disparities between urban and rural regions, educational levels and social classes. Hypertension and diabetes are also additional risk factors predicting alarming mortality rates. We propose here a review of the determinants of metabolic syndrome in Tunisia and the overall cardiometabolic risk factors.

Genetic and lifestyle predictors of ischemic stroke severity and outcome

BACKGROUND

Different models that include clinical variables and blood markers have been investigated to predict acute ischemic stroke treatment course and recovery.

AIM

The aim of the study was to investigate associations between lipid levels, lifestyle factors, hemostatic (F5, F2, SERPINE1, F13A1, and FGB), and atherogenic (APOA5 and ACE) gene variants and acute ischemic stroke (AIS) severity.

MATERIALS AND METHODS

This study included 250 patients with AIS in which F5, F2, SERPINE1, F13A1, FGB, APOA5, and ACE genotypes were determined. Total cholesterol (TC), high-density cholesterol, low-density cholesterol, and triglycerides concentrations were measured within 24 h of the AIS onset. Examination of the neurological deficit was done using National Institutes of Health Stroke Scale/Score (NIHSS).

RESULTS

APOA5 genotype [TC + CC] was more frequent (P = 0.026) in patients with the NIHSS score ≥ 21. Univariate regression analysis has shown that triglycerides (OR 0.55, 95% CI 0.34-0.91; P = 0.019), obesity (0.28, 95% CI 0.10-0.73; P = 0.010), age (OR 1.08, 95% CI 1.04-1.13; P < 0.001), and APOA5 genotype (TC + CC) (OR 2.40, 95% CI 1.10-5.25; P = 0.034) are significantly associated with a severe stroke. When all variables were included in model age (OR 1.06, 95% CI 1.01-1.11; P = 0.018), obesity (OR 0.25, 95% CI 0.08-0.77; P = 0.016) and APOA5 genotype (TC + CC) (OR 3.26, 95% CI 1.29-8.23; P = 0.012) remained significant for the risk of severe AIS.

CONCLUSION

APOA5 genotype (TC + CC), age, and obesity could be used as prognostic risk factors for a very severe stroke (NIHSS ≥ 21).

Association of apolipoprotein A1 and A5 polymorphisms with stroke subtypes in Han Chinese people in Taiwan

BACKGROUND AND PURPOSES

Stroke is a leading cause of death and serious disability worldwide. Now, evidences indicate that dyslipidemia may play an important role in stroke. APOA1 and APOA5 involve in lipid metabolism. In this study, we investigated the association of APOA1 rs670 and APOA5 rs662799 with different stroke subtypes in the Han Chinese population of Taiwan.

METHODS

A total of 1751 participants, including 459 control subjects, 606 large artery atherosclerosis (LAA), 339 small vessel occlusion (SVO), and 347 hypertensive intracranial hemorrhage (HICH), were enrolled. The presence of rs670 and rs662799 was analyzed through polymerase chain react ion and matrix-assisted laser desorption/ionization-time-of-flight-mass spectrometry.

RESULTS

Notably, the frequency of the rs662799 C allele was significantly lower in the SVO patients than in the controls (24.36% vs. 29.74%, P = 0.024). The frequencies of heterozygote TC [odd ratio (OR) = 0.732, 95% confidence interval (CI) = 0.544-0.984, P = 0.038] and TC + CC (OR = 0.719, 95% CI = 0.542-0.953, P = 0.022) genotypes were significantly lower in the SVO patients than in the controls. In addition, triglyceride levels in individuals carrying the rs662799 TC + CC genotype were significantly higher than in those carrying the TT genotype, especially in older age, female, and body mass index (BMI) ≥ 25 groups. On the contrary, the low-density lipoprotein-cholesterol (LDL-C) was significantly lower in rs662799 TC + CC genotype than TT genotype. The BMI was significantly lower in subjects with rs662799 TC + CC genotype than those with TT genotype, especially in older age and female. High-density lipoprotein-cholesterol (HDL-C) levels were higher in individuals carrying the rs670 GG genotype than in those carrying the AG + AA genotype, especially in BMI < 25 group. Logistic regression analysis showed that the rs662799 C allele (TC + CC) was an independent protective factor for SVO after adjustment for conventional risk factors (OR = 0.709, 95% CI = 0.526-0.956; P = 0.024).

CONCLUSION

GG genotype of rs670 is correlated with high serum HDL-C levels, whereas TC + CC genotype of rs662799 is associated with high serum triglyceride and low LDL and BMI levels. In addition, the rs662799 C allele (TC + CC) is an independent protective factor for SVO in the Han Chinese population in Taiwan.

New insights into apolipoprotein A5 in controlling lipoprotein metabolism in obesity and the metabolic syndrome patients

Apolipoprotein A5 (apoA5) has been identified to play an important role in lipid metabolism, specifically in triglyceride (TG) and TG-rich lipoproteins (TRLs) metabolism. Numerous evidence has demonstrated for an association between apoA5 and the increased risk of obesity and metabolic syndrome, but the mechanism remains to be fully elucidated. Recently, several studies verified that apoA5 could significantly reduce plasma TG level by stimulating lipoprotein lipase (LPL) activity, and the intracellular role of apoA5 has also been proved since apoA5 is associated with cytoplasmic lipid droplets (LDs) and affects intrahepatic TG accumulation. Furthermore, since adipocytes provide the largest storage depot for TG and play a crucial role in the development of obesity, we could infer that apoA5 also acts as a novel regulator to modulate TG storage in adipocytes. In this review, we focus on the association of gene and protein of apoA5 with obesity and metabolic syndrome, and provide new insights into the physiological role of apoA5 in humans, giving a potential therapeutic target for obesity and associated disorders.

Genome-wide association study identifies a missense variant at APOA5 for coronary artery disease in Multi-Ethnic Cohorts from Southeast Asia

Recent genome-wide association studies (GWAS) have identified multiple loci associated with coronary artery disease (CAD) among predominantly Europeans. However, their relevance to multi-ethnic populations from Southeast Asia is largely unknown. We performed a meta-analysis of four GWAS comprising three Chinese studies and one Malay study (Total N = 2,169 CAD cases and 7,376 controls). Top hits (P < 5 × 10-8) were further evaluated in 291 CAD cases and 1,848 controls of Asian Indians. Using all datasets, we validated recently identified loci associated with CAD. The involvement of known canonical pathways in CAD was tested by Ingenuity Pathway Analysis. We identified a missense SNP (rs2075291, G > T, G185C) in APOA5 for CAD that reached robust genome-wide significance (Meta P = 7.09 × 10-10, OR = 1.636). Conditional probability analysis indicated that the association at rs2075291 was independent of previously reported index SNP rs964184 in APOA5. We further replicated 10 loci previously identified among predominantly Europeans (P: 1.33 × 10-7-0.047). Seven pathways (P: 1.10 × 10-5-0.019) were identified. We identified a missense SNP, rs2075291, in APOA5 associated with CAD at a genome-wide significance level and provided new insights into pathways contributing to the susceptibility to CAD in the multi-ethnic populations from Southeast Asia.

The impact of APOA5, APOB, APOC3 and ABCA1 gene polymorphisms on ischemic stroke: Evidence from a meta-analysis

BACKGROUND AND AIMS

Genetic studies have been reported on the association between APOA5, APOB, APOC3 and ABCA1 gene polymorphisms and ischemic stroke, but results remain controversial. Hence, this meta-analysis aimed to infer the causal relationships of APOA5 (rs662799, rs3135506), APOB (rs693, rs1042031, rs1801701), APOC3 (rs4520, rs5128, rs2854116, rs2854117) and ABCA1 rs2230806 with ischemic stroke risk.

METHODS

A systematic review was performed for all the articles retrieved from multiple databases, up until March 2017. Data were extracted from all eligible studies, and meta-analysis was carried out using RevMan 5.3 and R package 3.2.1. The strength of association between each studied polymorphism and ischemic stroke risk was measured as odds ratios (ORs) and 95% confidence intervals (CIs), under fixed- and random-effect models.

RESULTS

A total of 79 studies reporting on the association between the studied polymorphisms and ischemic stroke risk were identified. The pooled data indicated that all genetic models of APOA5 rs662799 (ORs = 1.23-1.43), allelic and over-dominant models of APOA5 rs3135506 (ORs = 1.77-1.97), APOB rs1801701 (ORs = 1.72-2.13) and APOB rs1042031 (ORs = 1.66-1.88) as well as dominant model of ABCA1 rs2230806 (OR = 1.31) were significantly associated with higher risk of ischemic stroke. However, no significant associations were observed between ischemic stroke and the other five polymorphisms, namely ApoB (rs693) and APOC3 (rs4520, rs5128, rs2854116 and rs2854117), under any genetic model.

CONCLUSIONS

The present meta-analysis confirmed a significant association of APOA5 rs662799 CC, APOA5 rs3135506 CG, APOB rs1801701 GA, APOB rs1042031 GA and ABCA1 rs2230806 GG with increased risk of ischemic stroke.

The association between apolipoprotein A1-C3-A5 gene cluster promoter polymorphisms and risk of ischemic stroke in the northern Chinese Han population

Objective

Given its effects on lipid metabolism, the apolipoprotein A1-C3-A5 (APOA1-C3-A5) gene cluster is thought to play an important role in ischemic stroke pathogenesis. Here, we evaluated whether the APOA1-C3-A5 cluster is associated with ischemic stroke in the northern Chinese Han population.

Methods

This case–control study analyzed 812 patients with ischemic stroke and 844 healthy controls with regard to four APOA1-C3-A5 cluster promoter single nucleotide polymorphisms (SNPs), rs670, rs2854116, rs2854117, and rs662799, using the SNaPshot Multiplex sequencing assay. Potential associations among ischemic stroke, genotyping, and allele frequencies were assessed.

Results

APOA1 rs670 CT/TT genotypes, APOA5 rs662799 AG/GG genotypes, and the APOC3 rs2854116 CC genotype were associated with an increased risk of ischemic stroke according to multivariate logistic analysis after adjusting for confounding factors. A significantly increased risk for ischemic stroke was also identified among high-risk haplotypes (C-C-T-A and T-T-C-A) for rs670–rs2854116–rs2854117–rs662799.

Conclusion

This study showed that rs670, rs2854116, and rs662799 SNPs of the APOA1-C3-A5 cluster are associated with ischemic stroke in the northern Chinese Han population.

Genetic Variants Associated with Gestational Hypertriglyceridemia and Pancreatitis

Severe hypertriglyceridemia is a well-known cause of pancreatitis. Usually, there is a moderate increase in plasma triglyceride level during pregnancy. Additionally, certain pre-existing genetic traits may render a pregnant woman susceptible to development of severe hypertriglyceridemia and pancreatitis, especially in the third trimester. To elucidate the underlying mechanism of gestational hypertriglyceridemic pancreatitis, we undertook DNA mutation analysis of the lipoprotein lipase (LPL), apolipoprotein C2 (APOC2), apolipoprotein A5 (APOA5), lipase maturation factor 1 (LMF1), and glycosylphosphatidylinositol-anchored high-density lipoprotein-binding protein 1 (GPIHBP1) genes in five unrelated pregnant Chinese women with severe hypertriglyceridemia and pancreatitis. DNA sequencing showed that three out of five patients had the same homozygous variation, p.G185C, in APOA5 gene. One patient had a compound heterozygous mutation, p.A98T and p.L279V, in LPL gene. Another patient had a compound heterozygous mutation, p.A98T & p.C14F in LPL and GPIHBP1 gene, respectively. No mutations were seen in APOC2 or LMF1 genes. All patients were diagnosed with partial LPL deficiency in non-pregnant state. As revealed in our study, genetic variants appear to play an important role in the development of severe gestational hypertriglyceridemia, and, p.G185C mutation in APOA5 gene appears to be the most common variant implicated in the Chinese population. Antenatal screening for mutations in susceptible women, combined with subsequent interventions may be invaluable in the prevention of potentially life threatening gestational hypertriglyceridemia-induced pancreatitis.

Association of two common polymorphisms of apolipoprotein A5 gene with metabolic syndrome indicators in a North Iranian population, a cross-sectional study

Background

Metabolic syndrome is an obesity dependent disorder with a worldwide high prevalence. Regarding the high prevalence of Metabolic syndrome in Iran we analyzed the influence of -1131T>C (rs662799) and c.56C>G (S19W, rs3135506) polymorphisms of the novel apolipoprotein gene, ApoA5, on some Metabolic Syndrome indicators in population from north of Iran.

Methods

199 volunteers from Babol city-Iran were divided in two groups of low (N = 99, TG ≤ 103 mg/dl) and high (N = 100, TG ≥ 150 mg/dl) serum levels of Triglycerides (TG). We amplified the gene fragments containing -1131T>C and c.56C>G polymorphisms by PCR method and revealed the polymorphisms by RFLP analysis.

Results

We found a significant association (p = 0.016, Independent t-test) between high levels of TG and -1131T>C polymorphism but not between this polymorphism and serum HDL-C concentrations. Carriers of the C allele had a 1.97 times higher odds ratio to be in the high-TG group than those of the TT genotype (95%, CI = 1.05-3.68). We observed no association between -1131T>C polymorphism with either Waist-to-Hip Ratio (WHR) or Body-Mass-Index (BMI). In the case of c.56C>G polymorphism, although it showed a significant relationship with WHR (p = 0/040, Independent t-test), but failed to correlate with either levels of TG (p = 0.594) or HDL-C (p = 0.640) in serum.

Conclusion

Our study confirms that ApoA5 gene polymorphisms, -1131T>C and c.56C>G are associated with the two criteria of Metabolic Syndrome, TG and WHR, respectively.

Genetic polymorphism of apolipoprotein A5 gene and susceptibility to type 2 diabetes mellitus: a meta-analysis of 15,137 subjects

BACKGROUND

Several studies have investigated whether the polymorphism in the apolipoprotein A5 (APOA5) is associated with type 2 diabetes mellitus (T2DM) risk. However, those studies have produced inconsistent results. The purpose of this study was to investigate whether the APOA5 -1131T/C polymorphism (rs662799) confers significant susceptibility to T2DM using a meta-analysis.

METHODS

PubMed, Embase, Web of Science, Cochrane database, CBMdisc, CNKI and Google Scholar were searched to get the genetic association studies. All statistical analyses were done with Stata 11.0.

RESULTS

A total of 19 studies included 4,767 T2DM cases and 10,370 controls (four studies involving 555 T2DM cases and 2958 controls were performed among Europeans and 15 studies involving 4212 T2DM cases and 7412 controls were performed among Asians) were combined showing significant association between the APOA5 -1131T/C polymorphism and T2DM risk (for C allele vs. T allele: OR = 1.28, 95% CI = 1.17-1.40, p<0.00001; for C/C vs. T/T: OR = 1.57, 95% CI = 1.35-1.83, p<0.00001; for C/C vs. T/C+T/T: OR = 1.36, 95% CI = 1.18-1.57, p<0.0001; for C/C+T/C vs. T/T: OR = 1.32, 95% CI = 1.16-1.51, p<0.0001). In the subgroup analysis by ethnicity, significant association was also found among Asians (for C allele vs. T allele: OR = 1.31, 95% CI = 1.22-1.40, p<0.00001; for C/C vs. T/T: OR = 1.61, 95% CI = 1.38-1.88, p<0.00001; for C/C vs. T/C+T/T: OR = 1.39, 95% CI = 1.20-1.61, p<0.0001; for C/C+T/C vs. T/T: OR = 1.42, 95% CI = 1.25-1.62, p<0.00001). However, no significant association was found between the APOA5 -1131T/C polymorphism and T2DM risk among Europeans.

CONCLUSIONS

The present meta-analysis suggests that the APOA5 -1131T/C polymorphism is associated with an increased T2DM risk in Asian population.