4G/5G polymorphism of PAI-1 gene and Alu-repeat I/D polymorphism of TPA gene in Turkish patients with polycystic ovary syndrome

Tale of two systems: the intertwining duality of fibrinolysis and lipoprotein metabolism

Fibrinolysis is an enzymatic process that breaks down fibrin clots, while dyslipidemia refers to abnormal levels of lipids and lipoproteins in the blood. Both fibrinolysis and lipoprotein metabolism are critical mechanisms that regulate a myriad of functions in the body, and the imbalance of these mechanisms is linked to the development of pathologic conditions, such as thrombotic complications in atherosclerotic cardiovascular diseases. Accumulated evidence indicates the close relationship between the 2 seemingly distinct and complicated systems-fibrinolysis and lipoprotein metabolism. Observational studies in humans found that dyslipidemia, characterized by increased blood apoB-lipoprotein and decreased high-density lipoprotein, is associated with lower fibrinolytic potential. Genetic variants of some fibrinolytic regulators are associated with blood lipid levels, supporting a causal relationship between these regulators and lipoprotein metabolism. Mechanistic studies have elucidated many pathways that link the fibrinolytic system and lipoprotein metabolism. Moreover, profibrinolytic therapies improve lipid panels toward an overall cardiometabolic healthier phenotype, while some lipid-lowering treatments increase fibrinolytic potential. The complex relationship between lipoprotein and fibrinolysis warrants further research to improve our understanding of the bidirectional regulation between the mediators of fibrinolysis and lipoprotein metabolism.

Intracellular tPA-PAI-1 interaction determines VLDL assembly in hepatocytes

Apolipoprotein B (apoB)-lipoproteins initiate and promote atherosclerotic cardiovascular disease. Plasma tissue plasminogen activator (tPA) activity is negatively associated with atherogenic apoB-lipoprotein cholesterol levels in humans, but the mechanisms are unknown. We found that tPA, partially through the lysine-binding site on its Kringle 2 domain, binds to the N terminus of apoB, blocking the interaction between apoB and microsomal triglyceride transfer protein (MTP) in hepatocytes, thereby reducing very-low-density lipoprotein (VLDL) assembly and plasma apoB-lipoprotein cholesterol levels. Plasminogen activator inhibitor 1 (PAI-1) sequesters tPA away from apoB and increases VLDL assembly. Humans with PAI-1 deficiency have smaller VLDL particles and lower plasma levels of apoB-lipoprotein cholesterol. These results suggest a mechanism that fine-tunes VLDL assembly by intracellular interactions among tPA, PAI-1, and apoB in hepatocytes.

Association of single nucleotide polymorphisms (4G/5G) of plasminogen activator inhibitor-1 and the risk factors for placenta-related obstetric complications

BACKGROUND

Placenta-related obstetric complications (PROCs) such as miscarriage, fetal growth restriction, preeclampsia, and preterm birth are the major causes of maternal and fetal morbidity and mortality. The objective of this study was to search the relevance of plasminogen activator inhibitor-1 (PAI-1) polymorphisms and co-morbidities and the risk factors for PROCs such as miscarriage, fetal growth restriction, preeclampsia, and preterm birth.

METHOD

This retrospective study analyzed the PAI-1 genotype in a cohort of 268 multiparous women with poor obstetric history. Poor obstetric history was defined as the presence of at least one of the PROCs and/or poor gestational outcomes at the previous pregnancy/pregnancies.

RESULTS

5G allele frequency was higher than the 4G allele frequency in the cohort (0.767 vs. 0.233). The frequencies of having at least one risk factor are relatively similar among the different PAI-1 genotypes ( P  > 0.05). However, the presence of MTHFR polymorphisms (homozygous and compound heterozygous forms of C677T and A1298G) and hereditary thrombophilia (Factor V Leiden and prothrombin G20210A gene mutations, and FXIII deficiency) were found to be associated with PAI 4G/4G ( P  = 0.048) and 5G/5G ( P  = 0.022) genotypes, respectively. Significant differences were not observed in other risk factors and co-morbidities such as autoimmune disorders, chronic inflammatory diseases, history of venous thromboembolism, carbohydrate metabolism disorders, hyperlipidemia, cardiovascular and cerebrovascular diseases depending on PAI-1 genotypes ( P  > 0.05).

CONCLUSION

MTHFR polymorphisms were found to be associated with PAI 4G/4G genotype, while 5G/5G genotype was observed more frequently in hereditary thrombophilia cases.

Plasminogen activator inhibitor-1 -675 4G/5G polymorphism and polycystic ovary syndrome risk: a meta analysis

PURPOSE

Several studies have reported that excessive amounts of plasminogen activator inhibitor-1(PAI-1) might increase the incidence of polycystic ovary syndrome(PCOS), but so far the published results were inconsistent. The aim of this study was to further investigate the association between PAI-1 gene polymorphism and the susceptibility to PCOS by performing a meta-analysis.

METHODS

A comprehensive literature search for relevant studies was conducted on google scholar, PubMed, the Chinese National Knowledge Infrastructure (CNKI) and the Chinese Biomedical Literature Database (CBM). This meta-analysis was performed using the STATA 11.0 software and the pooled odds ratio (OR) with 95% confidence interval (CI) was calculated.

RESULTS

Ten case-control studies were included in this meta-analysis with a total of 2,079 cases and 1,556 controls. The results showed that PAI-1 -675 4G/5G polymorphism may increase the risk of PCOS, especially among Asian populations. However, there was no statistically significant association between the polymorphism and PCOS risk in Caucasians.

CONCLUSION

Our meta-analysis suggests that PAI-1 -675 4G/5G polymorphism may contribute to increasing susceptibility to PCOS in Asians. Detection of the PAI-1 gene polymorphism might be a promising biomarker for the susceptibility of PCOS.

Genetic polymorphisms associated with steroids metabolism and insulin action in polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is an endocrinopathy associated with infertility, diabetes and cardiovascular events. This study aimed to correlate polymorphisms of genes involved in the biosynthesis and metabolism of steroids and insulin action (CYP17A1, CYP19A1, AR, ESR1, ESR2, INSR, IGF2 and PAI1) with clinical and biochemical parameters of PCOS. DNA was extracted from peripheral blood samples obtained from 117 PCOS and 105 healthy women. The PAI1 insertion/deletion (-675 ins/delG) polymorphism (rs1799768) was genotyped by PCR-SSCP. CYP19A1 [TTTA](n), AR [CAG](n), ESR1 [TA](n), and ESR2 [CA](n) genes were evaluated by PCR-based GeneScan analysis, while CYP17A1 5'UTR (rs743572), INSR 1058 CT (rs1799817), and IGF2 3'UTR GA (rs680) polymorphisms were evaluated by PCR-RFLP. The results showed a prevalence of PAI1 4G5G+4G4G genotypes in PCOS (p = 0.025). Younger PCOS women showed a predominance of CT+TT, GA+AA and 4G5G+4G4G genotypes of INSR, IGF2, and PAI1 (p = 0.0499, p = 0.0300, p = 0.0350, respectively). AR shorter alleles (≤ 20 repeats) were significantly associated with higher serum levels of total testosterone (TT, p = 0.0086). In conclusion, PAI1 polymorphism seems to be associated with the risk of PCOS development. Younger PCOS women had specific genotypes of INSR, IGF2 and PAI1 genes. AR shorter alleles can be associated with higher serum levels of TT in PCOS patients.

Effect Of G2706A and G1051A polymorphisms of the ABCA1 gene on the lipid, oxidative stress and homocystein levels in Turkish patients with polycystıc ovary syndrome

BACKGROUND

Obesity, insulin resistance and hyperandrogenism, crucial parameters of Polycystic ovary syndrome (PCOS) play significant pathophysiological roles in lipidemic aberrations associated within the syndrome. Parts of the metabolic syndrome (low HDL and insulin resistance) appeared to facilitate the association between PCOS and coronary artery disease, independently of obesity. ABCA1 gene polymorphism may be altered this components in PCOS patients.In this study, we studied 98 PCOS patients and 93 healthy controls. All subjects underwent venous blood drawing for complete hormonal assays, lipid profile, glucose, insulin, malondialdehyde, nitric oxide, disulfide levels and ABCA genetic study.

RESULTS

In PCOS group fasting glucose, DHEAS, 17-OHP, free testosterone, total-cholesterol, triglyceride, LDL-cholesterol and fibrinogen were significantly different compare to controls. The genotype ABCA G2706A distribution differed between the control group (GG 60.7%, GA 32.1%, AA 7.1%) and the PCOS patients (GG 8.7%, GA 8.7%, AA 76.8%). The frequency of the A allele (ABCAG2706A) was higher in PCOS patients than control group with 13,0% and 23,2%, respectively. In this study, the homocystein and insulin levels were significantly higher in PCOS patients with ABCA G1051A mutant genotype than those with heterozygote and wild genotypes.

CONCLUSIONS

We found higher percentage of AA genotype and A allele of ABCA G2706A in PCOS patients compare to controls. The fasting insulin and homocystein levels were significantly higher in PCOS patients with ABCA G1051A mutant genotype than those with heterozygote and wild genotypes.

Association of angiotensin converting enzyme (ACE) gene I/D polymorphism and polycystic ovary syndrome (PCOS)

This study was conducted in Turkish patients with polycystic ovary syndrome to determine the frequency of I/D polymorphism genotypes of angiotensin converting enzyme gene, and to examine the role of this polymorphism in polycystic ovary syndrome development. Genomic DNA obtained from 200 persons (100 patients with polycystic ovary syndrome and 100 healthy controls) was used in the study. DNA was multiplied by polymerase chain reaction using I and D allele-specific primers. Polymerase chain reaction products were assessed with a charge coupled device (CCD) camera by being exposed to 2% agarose gel electrophoresis. There was statistically significant difference between the groups with respect to genotype distribution (p<0.001). The D allele frequency was indicated as 68% and I allele was as 32% in the patients, whereas it was 51.5-48.5% respectively in the control group. As a result of our study we may assert that angiotensin converting enzyme gene I/D polymorphism DD genotype should be considered as a genetic marker in polycystic ovary syndrome development in this Turkish study population.

Genetic polymorphisms of FSHR, CYP17, CYP1A1, CAPN10, INSR, SERPINE1 genes in adolescent girls with polycystic ovary syndrome

BACKGROUND

Polycystic ovary syndrome (PCOS), whose genetic basis is not completely well understood, is the most common endocrine disorder in women and it typically develops during adolescence. The aim of this study is to investigate the possible association between single nucleotide polymorphisms (SNPs) of FSHR, CYP17, CYP1A1, CAPN10, INSR, SERPINE1 genes and PCOS in adolescent girls.

METHODS

DNA samples from forty-four adolescent girls with PCOS and 50 healthy controls were analyzed by PCR-RFLP and direct DNA sequencing to determine the genotypic frequency of 17 different polymorphic loci on the FSHR (A307T, N680S), CYP17 (-34 T/C), CYP1A1 (T6235C), CAPN10 (44, 43, 19, 63), INSR (exon 17 C/T), SERPINE1 (4G/5G) genes. Genotyping of exon 12 (six polymorphisms) and intron 12 (one polymorphism) of INSR gene by direct DNA sequencing was performed for the first time in this study.

RESULTS

No significant differences were observed in the genotype and allele distributions of above mentioned polymorphisms between cases and control groups.

CONCLUSION

Our data does not support an association between SNPs of FSHR, CYP17, CYP1A1, CAPN10, INSR, SERPINE1 genes and susceptibility to PCOS or related traits in Turkish adolescent girls.

Apolipoprotein E gene polymorphism and polycystic ovary syndrome patients in Western Anatolia, Turkey

PURPOSE

Dyslipidemia, cardiovascular disease and hypertension are more frequently seen in patients with PCOS than in normal patients. We aimed at evaluating the distribution of Apo E alleles that can influence cardiovascular risk of the PCOS patients and control subjects.

METHODS

In this study, 129 young women with PCOS and 91 healthy women were included. In all subjects we performed hormonal, biochemical and Apo E genetic analysis.

RESULTS

The Apo E3 allele was found at a significantly higher frequency in the PCOS patient group compared with the control group. The Apo E2 allele was found at a significantly higher frequency in the control group compared with the patient group with PCOS.

CONCLUSIONS

Although there were genotype and allele differences between control and patient groups in this study, no statistically significant change was determined in lipid and other cardiovascular risk factors in connection with allele and genotype.

Functional genetic polymorphisms and female reproductive disorders: Part I: Polycystic ovary syndrome and ovarian response

BACKGROUND

The identification of polymorphisms associated with a disease can help to elucidate its pathogenesis, and this knowledge can be used to improve prognosis for women with a particular disorder, such as polycystic ovary syndrome (PCOS). Since an altered response to ovarian stimulation is also a characteristic of the disease, further knowledge about its aetiology could help in defining the parameters that determine the response of an individual to ovarian stimulation.

METHODS

PubMed and EMBASE databases were systematically searched for gene association studies published until the end of August 2007, using search criteria relevant to PCOS and ovarian response to stimulation. Data from additional papers identified through hand searches were also included; 139 publications were reviewed.

RESULTS

Several genes involved in ovarian function and metabolism are associated with increased susceptibility to PCOS, but none is strong enough to correlate alone with susceptibility to the disease, or response to therapy. A single-nucleotide polymorphism in exon 10 of the FSH receptor (FSHR) gene, FSHR p.N680S, was consistently identified as having a significant association with ovarian response to FSH.

CONCLUSIONS

No consistent association between gene polymorphism and PCOS could be identified. The FSHR gene may play a significant role in the success of ovarian stimulation, and can be used as a marker to predict differences in FSHR function and ovarian response to FSH. Genotyping the FSHR p.N680S polymorphism may provide a means of identifying a population of poor responders before in vitro fertilization procedures are initiated.