FABP2 Ala54Thr polymorphism and diabetes in Chilean elders

Polymorphism in genes encoding two fatty acid binding proteins increases risk of ischemic stroke in a Chinese Han population

Background: Dyslipidemia is an independent predictor of ischemic stroke (IS). Genetic variations in lipid-metabolism related genes may increase the risk of IS. Fatty acid-binding protein 1 (FABP1) and fatty acid-binding protein 2 (FABP2) are lipid chaperones responsible for lipid transport and metabolism. The present study aimed to determine the association between FABP1 or FABP2 and ischemic stroke.

Methods: A total of 251 participants were recruited composed of 138 patients with ischemic stroke and 113 healthy subjects. DNA was extracted from peripheral blood samples. The rs2241883 polymorphism in FABP1 and rs1799883 polymorphism in FABP2 were genotyped using polymerase chain reaction-restriction fragment length polymorphism. Generalized multifactor dimensionality reduction (GMDR) was used to find out the interaction combinations between two SNPs and environmental factors.

Results: The GA genotype of FABP2 rs1799883 increased susceptibility to ischemic stroke under overdominant inheritance model (p = 0.042). After adjusting for the risk factors of IS, it was associated with a significantly higher risk of IS in the codominant inheritance model (adjust OR = 3.431, 95%CI = 1.060–11.103, p = 0.04). The interactions of FABP1 rs2241883 and FABP2 rs1799883 were not associated with IS risk (p = 0.172). Moreover, interaction analysis of two genes (rs1799883 and rs2241883) and two environmental factors (smoking and alcohol consumption) was associated with an increased risk of IS (p = 0.011).

Conclusion: The GA genotype of FABP2 rs1799883, interactions between rs1799883, rs2241883 and smoking and alcohol consumption were associated with IS risk in Chinese Han populations.

Intestinal fatty acid binding protein Ala54Thr polymorphism is associated with peripheral atherosclerosis combined with type 2 diabetes mellitus

BACKGROUND

Intestinal fatty acid-binding protein 2 (FABP2) is expressed in enterocytes and binds saturated and unsaturated long-chain fatty acids. The FABP2 Ala54Thr polymorphism has been reported to effect lipid metabolism. The aim of the present study was to assess the relationship between this polymorphism and peripheral atherosclerosis combined with type 2 diabetes mellitus (T2DM) in an Egyptian population.

METHODS

The study was performed on 100 T2DM patients with peripheral atherosclerosis and 100 control subjects. The Ala54Thr polymorphism was analyzed by polymerase chain reaction-restriction fragment length polymorphism, whereas serum FABP2 levels were determined using ELISA. Fasting blood glucose, fasting serum insulin concentrations, HbA1c, lipid profile, body mass index (BMI) and systolic and diastolic blood pressure (SBP and DBP, respectively) were determined.

RESULTS

There was a higher frequency of the Thr54 allele among the patient group (P = 0.002). In Ala54/Thr54 heterozygotes and carriers of the rare Thr54/Thr54 genotype, there were significant increases in BMI and FABP2. Those with the Thr54/Thr54 genotype had significantly decreased high-density lipoprotein cholesterol (HDL-C) concentrations; in addition, those with the Thr54/Thr54 genotype had significantly higher SBP and DBP than subjects with the Ala54/Ala54 and Ala54/Thr54 genotypes. There was a positive correlation between FABP2 levels and BMI, SBP and DBP, and a negative correlation with HDL-C.

CONCLUSIONS

The Thr54 allele of the FABP2 Ala54Thr polymorphism was associated with an increased incidence of peripheral atherosclerosis combined with T2DM in the population studied.

The Ala54Thr Polymorphism of the Fatty Acid Binding Protein 2 Gene Modulates HDL Cholesterol in Mexican-Americans with Type 2 Diabetes

The alanine to threonine amino acid substitution at codon 54 (Ala54Thr) of the intestinal fatty acid binding protein (FABP2) has been associated with elevated levels of insulin and blood glucose as well as with dyslipidemia. The aim of this study was to characterize the effect of this FABP2 polymorphism in Mexican-Americans with type 2 diabetes (T2D) in the context of a three-month intervention to determine if the polymorphism differentially modulates selected clinical outcomes. For this study, we genotyped 43 participant samples and performed post-hoc outcome analysis of the profile changes in fasting blood glucose, HbA1c, insulin, lipid panel and body composition, stratified by the Ala54Thr polymorphism. Our results show that the Thr54 allele carriers (those who were heterozygous or homozygous for the threonine-encoding allele) had lower HDL cholesterol and higher triglyceride levels at baseline compared to the Ala54 homozygotes (those who were homozygous for the alanine-encoding allele). Both groups made clinically important improvements in lipid profiles and glycemic control as a response to the intervention. Whereas the Ala54 homozygotes decreased HDL cholesterol in the context of an overall total cholesterol decrease, Thr54 allele carriers increased HDL cholesterol as part of an overall total cholesterol decrease. We conclude that the Ala54Thr polymorphism of FABP2 modulates HDL cholesterol in Mexican-Americans with T2D and that Thr54 allele carriers may be responsive in interventions that include dietary changes.

Association between FABP2 Ala54Thr polymorphisms and type 2 diabetes mellitus risk: a HuGE Review and Meta-Analysis

Many studies have examined the association between the FABP2 (rs1799883) Ala54Thr gene polymorphism and type 2 diabetes mellitus risk (T2DM) in various populations, but their results have been inconsistent. To assess this relationship more precisely, A HuGE review and meta-analysis were performed. The PubMed and CNKI database was searched for case-control studies published up to April 2014. Data were extracted and pooled odds ratios (OR) with 95% confidence intervals (CI) were calculated. Ultimately, 13 studies, comprising 2020 T2DM cases and 2910 controls were included. Overall, for the Thr carriers (Ala/Thr and Thr/Thr) versus the wild-type homozygotes (Ala/Ala), the pooled OR was 1.18 (95% CI = 1.04–1.34, P = 0.062 for heterogeneity), for Thr/Thr versus Ala/Ala the pooled OR was 1.17 (95% CI = 1.05–1.41 P = 0.087 for heterogeneity). In the stratified analysis by ethnicity, the significantly risks were found among Asians but not Caucasians. This meta-analysis suggests that the FABP2 (rs1799883) Ala54Thr polymorphisms are associated with increased susceptibility to T2DM risk among Asians but not Caucasians.

Polymorphism Ala54Thr of fatty acid-binding protein 2 gene is not associated with stroke risk in Han population of Hunan China

Background

It is still unclear which genetic factors have a role in stroke. Studies have found that Ala54Thr of Fatty Acid-Binding Protein 2 (FABP2) was associated with stroke risk. This study aimed to determine whether polymorphism Ala54Thr of FABP2 is associated with stroke risk in the Hunan Han population of China.

Material/Methods

A total of 206 cerebral infarction (CI) patients, 185 cerebral hemorrhage (CH) patients, and 172 controls were enrolled in this study. Ala54Thr genotyping was done by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP).

Results

No significant difference was observed in genotypic distribution of FABP2 Ala54Thr between the stroke group (CI subgroup, CH subgroup included) and control group. In the stroke group, plasma triglycerides (TG) levels of subjects who carried Ala/Thr, Thr/Thr were significantly higher than those carrying Ala/Ala. In the control group, blood lipids were not significantly different among 3 genotypes of Ala54Thr. There was no significant difference in blood pressure and fasting blood sugar between the stroke group and controls.

Conclusions

Our study showed that Ala54Thr of FABP2 may be not associated with stroke risk but may be associated with plasma TG level of stroke patients from a Hunan Han population of China.

A54T polymorphism in the fatty acid binding protein 2 studies in a Saudi population with type 2 diabetes mellitus

Background

Fatty acid-binding protein 2 (FABP2) is an intracellular protein expressed exclusively in the enterocytes of proximal small intestine. FABP2 has a high affinity for saturated and unsaturated long-chain fatty acids and is believed to be involved in the absorption and transport of dietary fatty acids.

Methods

This is a case–control study conceded in 438 T2DM cases and 460 subjects with normal glucose levels and non-obese considered as healthy controls. Allelic discrimination was performed using TaqMan single-nucleotide polymorphism was carried out by real time-polymerase chain reaction (RT-PCR) assays using purified DNA.

Results

Clinical data and anthropometric measurements except age, glucose levels and lipid profile of the patients were significantly different from those of the controls (p < 0.05). Statistical analyses failed to show any type of significant association of the polymorphism between cases and controls. However logistic regression analyses was suggests that the TT genotype is significantly associated with male patients (p = 0.001). None of the allele or genotypes of FABP2 A54T was associated with T2DM cases versus the controls (AT genotype, OR = 0.85 (0.64-1.12), p = 0.25; TT genotype, OR = 0.66 (0.39-1.11), p = 0.11; T allele, 0.82 (0.67-1.02), p = 0.08).

Conclusion

In conclusion, this study suggests that the above named variant in FABP2 gene is not potential contributor to the risk of T2DM and related traits in a Saudi population. However TT genotype is a risk factor for the disease in males.

Comparative evolutionary genomics of medaka and three-spined stickleback fabp2a and fabp2b genes with fabp2 of zebrafish

Here we describe the evolutionary relationship of the duplicated intestinal fatty acid binding protein genes fabp2a and fabp2b from medaka and three-spined stickleback by comparing them to the well-studied fabp2 gene from zebrafish. The duplicated fabp2 genes from medaka and three-spined stickleback consist of four exons separated by three introns, which code for a polypeptide of 132 amino acids. Fabp2a and Fabp2b of medaka and three-spined stickleback share highest sequence identity with zebrafish Fabp2. All Fabp2/FABP2 sequences from vertebrates form a distinct clade in a neighbor-joining phylogenetic tree with a robust 100% bootstrap value, which indicates that the medaka and three-spined stickleback fabp2a and fabp2b are orthologs of zebrafish fabp2. The syntenic genes of fabp2a and fabp2b from medaka and three-spined stickleback were shown to be conserved with the syntenic genes of fabp2/FABP2 from zebrafish and human, evidence that the duplicated fabp2 genes from medaka and three-spined stickleback most likely arose from the teleost-specific whole-genome duplication. The tissue-specific distribution of medaka and three-spined stickleback fabp2a and fabp2b transcripts, and zebrafish fabp2 transcripts, assayed by RT-qPCR suggests the acquisition of new function(s) by the medaka fabp2a, and the distinct evolution of fabp2b compared with fabp2a in the medaka and three-spined stickleback genomes.

Genetic determinants of glucose homeostasis

Type 2 diabetes is a complex metabolic disorder characterised by varying degrees of impairment in insulin secretion and resistance to the action of insulin. Considerable progress has been made recently in understanding the genetic determinants of diabetes. A logical next step is to describe how these variants relate to the underlying pathophysiological processes that lead to diabetes as this may provide insights into pathways to disease. These quantitative traits are, of course, of direct interest in themselves and a growing literature is now emerging on the genetic determinants of insulin secretion and insulin resistance. This review article focuses on describing the complex associations between type 2 diabetes risk variants and quantitative glycaemic traits and the relationship between variants initially discovered in association studies of these traits and risk of type 2 diabetes.

Identification and expression analysis of fabp2 gene from common carp Cyprinus carpio

Two complementary (c)DNA fragments, including the complete open reading frame of fabp2 from the common carp Cyprinus carpio, were cloned by reverse-transcription polymerase chain reaction (RT-PCR). Both were putative intestinal-type fabp genes, named fabp2a and fabp2b. fabp2b was mainly expressed in the intestine and the brain. This gene, however, was nearly not expressed in the liver, heart, pancreas and muscle. fabp2a was only expressed at a very low level in the intestine. Western blot also showed that Fabp2 is relatively highly expressed in the intestine and the brain. Immunohistochemical analysis revealed that Fabp2 is widely distributed in the mucosa of the intestine. These findings provide novel insights into the fabp2 gene molecular evolution, as well as its potential features in the intestine and the brain.

Genetic variants and the metabolic syndrome: a systematic review

Several candidate gene studies on the metabolic syndrome (MetS) have been conducted. However, for most single nucleotide polymorphisms (SNPs) no systematic review on their association with MetS exists. A systematic electronic literature search was conducted until the 2nd of June 2010, using HuGE Navigator. English language articles were selected. Only genes of which at least one SNP-MetS association was studied in an accumulative total population ≥ 4000 subjects were included. Meta-analyses were conducted on SNPs with three or more studies available in a generally healthy population. In total 88 studies on 25 genes were reviewed. Additionally, for nine SNPs in seven genes (GNB3, PPARG, TCF7L2, APOA5, APOC3, APOE, CETP) a meta-analysis was conducted. The minor allele of rs9939609 (FTO), rs7903146 (TCF7L2), C56G (APOA5), T1131C (APOA5), C482T (APOC3), C455T (APOC3) and 174G>C (IL6) were more prevalent in subjects with MetS, whereas the minor allele of Taq-1B (CETP) was less prevalent in subjects with the MetS. After having systematically reviewed the most studied SNP-MetS associations, we found evidence for an association with the MetS for eight SNPs, mostly located in genes involved in lipid metabolism.

Meta-analysis on the effect of the Ala54Thr polymorphism of the fatty acid-binding protein 2 gene on body mass index

BACKGROUND AND AIM

The results from studies published on the association of fatty acid-binding protein 2 (FABP2) Ala54Thr polymorphism with body mass index (BMI) are conflicting. In this meta-analysis, we investigated the association of the FABP2 Ala54Thr polymorphism with BMI.

METHODS AND RESULTS

We searched for articles published prior to June 2009 using PubMed, HugeNavigator and China National Knowledge Internet. The languages were limited to English and Chinese. Data on BMI were collected. A pooled weighted mean difference (WMD), together with 95% confidence interval (CI), was used for this meta-analysis. A total of 27 studies with 10 974 subjects were included in this meta-analysis. The pooled effect for dominant, recessive and co-dominant model comparisons did not suggest the significant association between the FABP2 Ala54Thr polymorphism and BMI in overall populations: WMD(fixed effects)=-0.00, 95% CI: (-0.16 to 0.15), p=0.99, WMD(random effects)=-0.00, 95% CI: (-0.16 to 0.15), p=0.99, p(Q)=0.77, I(2)=0%, WMD(fixed effects)=-0.12, 95% CI: (-0.39 to 0.14), p=0.35, WMD(random effects)=-0.12, 95% CI: (-0.39 to 0.14), p=0.35, p(Q)=0.47, I(2)=0% and WMD(fixed effects)=0.07, 95% CI: (-0.11 to 0.25), p=0.45, WMD(random effects)=0.07, 95% CI: (-0.11 to 0.25), p=0.45, p(Q)=0.90, I(2)=0%, respectively. The results from the comparisons of ThrThr versus AlaAla and AlaThr versus AlaAla showed no evidence that the FABP2 Ala54Thr polymorphism is significantly associated with BMI in overall populations (p>0.05). All the results from the subgroup analyses for these genetic models comparisons were not significant (p>0.05).

CONCLUSIONS

Our meta-analysis does not support the association between the FABP2 Ala54Thr polymorphism and BMI.

APOE and FABP2 Polymorphisms and History of Myocardial Infarction, Stroke, Diabetes, and Gallbladder Disease

Dysfunctional lipid metabolism plays a central role in pathogenesis of major chronic diseases, and genetic factors are important determinants of individual lipid profiles. We analyzed the associations of two well-established functional polymorphisms (FABP2 A54T and APOE isoforms) with past and family histories of 1492 population samples. FABP2-T54 allele was associated with an increased risk of past history of myocardial infarction (odds ratio (OR) = 1.51). Likewise, the subjects with APOE4, compared with E2 and E3, had a significantly increased risk of past history myocardial infarction (OR = 1.89). The OR associated with APOE4 was specifically increased in women for past history of myocardial infarction but decreased for gallstone disease. Interactions between gender and APOE isoforms were also significant or marginally significant for these two conditions. FABP2-T54 allele may be a potential genetic marker for myocardial infarction, and APOE4 may exert sex-dependent effects on myocardial infarction and gallbladder disease.

Polymorphisms in fatty acid binding protein 5 show association with type 2 diabetes

Genes for the fatty acid binding proteins (FABP) family encode small 14-15 kDa cytosolic proteins and can be regulated during type 2 diabetes mellitus (T2DM) and obesity. This study compared association of single nucleotide polymorphisms (SNPs) in FABP1-5 with T2DM in different ethnic groups. Associations with T2DM of SNPs in these proteins were assessed in African American (AA), non-Hispanic White (NHW), and Hispanic American (HA) individuals. A total of 650 DNA samples were genotyped; control samples were obtained from Coriell's North American Human Variation Panel Repository (NAHVP) of apparently healthy individuals and T2DM cases were taken from the American Diabetes Association GENNID Study. The rs454550 SNP of FABP5 showed a significant association with T2DM in NHW (OR: 9.03, 95% CI: 1.13-71.73, p=0.014). Our analysis also identified a new FABP5 SNP (nSNP) that showed a significant association with T2DM in NHW (OR: 0.44, 95% CI: 0.19-0.99, p=0.045) and AA (OR: 0.17, 95% CI: 0.03-0.80, p=0.016). The Ala54Thr FABP2 polymorphism was significantly associated with T2DM in HA individuals only (OR: 1.85, 95% CI: 1.05-3.27, p=0.032). All other FABP SNPs did not show association with T2DM. These findings suggest a potential distinct role(s) of SNPs in FABP5 and FABP2 genes in T2DM in different populations.

Association of the fatty acid-binding protein 2 gene Ala54Thr polymorphism with insulin resistance and blood glucose: a meta-analysis in 13451 subjects

BACKGROUND

The results from the published studies on the association of fatty acid-binding protein 2 (FABP2) Ala54Thr polymorphism with insulin resistance and blood glucose are conflicting. In this meta-analysis, we investigated the association of the FABP2 Ala54Thr polymorphism with insulin resistance and blood glucose.

METHODS

We collected data on fasting blood glucose and fasting insulin, 2-h blood glucose (2-h BG) and 2-h insulin (2-h insulin), and homeostasis model assessment insulin resistance index. A dominant model was used for this meta-analysis.

RESULTS

Thirty-one studies with 13 451 subjects were included in this meta-analysis. The carriers of Thr54 allele have significantly higher homeostasis model assessment insulin resistance index and marginally higher fasting insulin than the non-carriers: standardized mean difference (SMD) = 0.07, 95% confidence interval (CI, 0.02, 0.12), p = 0.007, p(heterogeneity) = 0.19 and SMD = 0.08, 95% CI (-0.01, 0.17), p = 0.07, p(heterogeneity) < 0.00001, respectively. A borderline significant association between the FABP2 Ala54Thr polymorphism and an increased 2-h BG was also detected under the dominant model: SMD = 0.10, 95% CI (0.00, 0.20), p = 0.05, p(heterogeneity) = 0.09. In addition, a borderline association between this polymorphism and an increased fasting blood glucose in populations of other ethnic origins was detected under the dominant model: SMD = 0.11, 95% CI (-0.00, 0.23), p = 0.06, p(heterogeneity) = 0.03.

CONCLUSIONS

Our meta-analysis suggests that the Thr54 allele of the FABP2 Ala54Thr is weakly associated with a higher degree of insulin resistance, higher level of fasting insulin and higher level of 2-h BG. Our meta-analysis also suggests a weak association between this polymorphism and an increased fasting blood glucose in populations of other ethnic origins under the dominant model.

Prevalence of the metabolic syndrome in Latin America and its association with sub-clinical carotid atherosclerosis: the CARMELA cross sectional study

Background

Metabolic syndrome increases cardiovascular risk. Limited information on its prevalence in Latin America is available. The Cardiovascular Risk Factor Multiple Evaluation in Latin America (CARMELA) study included assessment of metabolic syndrome in 7 urban Latin American populations.

Methods

CARMELA was a cross-sectional, population-based, observational study conducted in Barquisimeto, Venezuela; Bogota, Colombia; Buenos Aires, Argentina; Lima, Peru; Mexico City, Mexico; Quito, Ecuador; and Santiago, Chile. The prevalence of metabolic syndrome, defined according to the National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III), and associated carotid atherosclerosis were investigated in 11,502 participants aged 25 to 64 years.

Results

Across CARMELA cities, metabolic syndrome was most prevalent in Mexico City (27%) and Barquisimeto (26%), followed by Santiago (21%), Bogota (20%), Lima (18%), Buenos Aires (17%), and Quito (14%). In nondiabetic participants, prevalence was slightly lower but followed a comparable ranking. Overall, 59%, 59%, and 73% of women with high triglycerides, hypertension, or glucose abnormalities, respectively, and 64%, 48% and 71% of men with abdominal obesity, hypertension, or glucose abnormalities, respectively, had the full metabolic syndrome. Prevalence of metabolic syndrome increased with age, markedly so in women. Mean common carotid artery intima-media thickness (CCAIMT) and prevalence of carotid plaque increased steeply with increasing numbers of metabolic syndrome components; mean CCAIMT was higher and plaque more prevalent in participants with metabolic syndrome than without.

Conclusion

The prevalence of metabolic syndrome and its components by NCEP ATP III criteria was substantial across cities, ranging from 14% to 27%. CARMELA findings, including evidence of the association of metabolic syndrome and carotid atherosclerosis, should inform appropriate clinical and public health interventions.

Sequence Analysis of the Full-length cDNA and Protein Structure Homology Modeling of FABP2 from Paralichthys Olivaceus

Using zebrafish intestinal fatty acid-binding protein 2 (FABP2) mRNA sequence as the initial query probe, four highly homologous Paralichthys olivaceus EST sequences were retrieved from Genbank database. The assembled full-length cDNA contains the open reading frame of P. olivaceus FABP2 gene, which was validated by subsequent RT-PCR cloning. In the coding region, the average GC content is 56%, but it would reach 76.8% if only counting for the third base of the codons. The deduced P. olivaceus FABP2 polypeptide contains 132 amino acids (aa), with a predicted molecular size of 15.3 kD and pI at 6.74. This protein multiple-alignment has shown that this peptide is 75.7% identical to the corresponding homologous protein in Danio rerio. Among the 7 aa that are essential for FABP2 function, 3 were found to be conserved among P. olivaceus, Danio rerio, Tetraodon nigroviridi, Rattus norvegicus, and Homo sapiens. The study provides essential information on molecular evolution and function of FABP family.