Comparative metabolomic profiling of women undergoing in vitro fertilization procedures reveals potential infertility-related biomarkers in follicular fluid.

Infertility is a worldwide concern, affecting one in six couples throughout their reproductive period. Therefore, enhancing the clinical tools available to identify the causes of infertility may save time, money, and emotional distress for the involved parties. This study aims to annotate potential biomarkers in follicular fluid that are negatively affecting pregnancy outcomes in women suffering infertility-related diseases such as endometriosis, tuboperitoneal factor, uterine factor, and unexplained infertility, using a metabolomics approach through high-resolution mass spectrometry. Follicular fluid samples collected from women who have the abovementioned diseases and managed to become pregnant after in vitro fertilization procedures [control group (CT)] were metabolically compared with those from women who suffer from the same diseases and could not get pregnant after the same treatment [infertile group (IF)]. Mass spectrometry analysis indicated 10 statistically relevant differential metabolites in the IF group, including phosphatidic acids, phosphatidylethanolamines, phosphatidylcholines, phosphatidylinositol, glucosylceramides, and 1-hydroxyvitamin D3 3-D-glucopyranoside. These metabolites are associated with cell signaling, cell proliferation, inflammation, oncogenesis, and apoptosis, and linked to infertility problems. Our results indicate that understanding the IF's metabolic profile may result in a faster and more assertive female infertility diagnosis, lowering the costs, and increasing the probability of a positive pregnancy outcome.

Influence of lifestyle characteristics and VDR polymorphisms as risk factors for intervertebral disc degeneration: a case-control study.

BACKGROUND: Intervertebral disc degeneration (DD) is an important cause of low back pain and its precise aetiology is not fully understood, being attributed to cumulative environmental, biomechanical and genetic effects. The vitamin D plays a key role in regulation of calcium homeostasis and bone mineralization, exerting its biological activities by binding to a high-affinity receptor (VDR). Polymorphisms in VDR gene were previously associated with DD process, however with conflicting results. Here, we aimed to investigate the influence of lifestyle characteristics and VDR TaqI, BsmI, ApaI and FokI polymorphisms as risk factors for DD process. METHODS: Retrospective case-control study involving 231 participants: 119 with confirmed DD and 112 healthy controls. Genotyping of VDR polymorphisms was performed by PCR-RFLP and real-time PCR using TaqMan methodology. All patients answered a questionnaire regarding lifestyle characteristics, such as educational level, pain localization, smoking habits, engagement of physical activity, postural and load weight at work and familial history of disc degeneration. The variables were compared between groups and adjusted by age and gender. RESULTS: The case group was composed by 52% female and 48% male and the mean age was 40.0 years old, while in the control group 79% was female and 21% male and the mean age was 32.0 years old. Although gender distribution and mean age were different between groups, in the control group all participants were less than 45 years old and there was a prevalence of women in both groups. The factors that could be possibly associated to DD in the Brazilian population studied included smoking habits (26% in cases and 9% in controls, p = 0.003), lack of engagement in physical activity (observed in 77% of cases and 62% of controls, p = 0.018), and loading weight during work routine (58% in cases and 24% in controls, p ≤ 0.001). However, after adjusting by age and gender, only smoking habits remained associated to disc degeneration (p = 0.027). Considering the educational level, 35.2% of cases and 15.6% of controls had only the Elementary School, and 5.5% of DD group and 28.6% of control group had completed College (p = 0.025). In addition, educational level was directly associated to load weight at work (p = 0.012). Regarding VDR polymorphisms, no significant difference in genotype and allele frequencies between groups was observed. The haplotype analysis revealed that the combined wild-type alleles of TaqI, ApaI and FokI polymorphisms-TGT-was observed in a higher frequency in control group (p = 0.039). CONCLUSION: The findings suggested that smoking habits was a risk factor for disc degeneration in the population studied. Single analysis revealed no significant effects of VDR polymorphisms in disc degeneration process, while the combination of wild-type alleles of TaqI, ApaI and FokI polymorphisms, TGT haplotype, decreased the risk of the disease.

Association Between the FokI and ApaI Polymorphisms in the Vitamin D Receptor Gene and Intervertebral Disc Degeneration: A Systematic Review and Meta-Analysis.

BACKGROUND: Evidence supporting an association of intervertebral disc degeneration (DD) with polymorphisms of the vitamin D receptor (VDR) gene has been controversial. We performed a meta-analysis of these studies to determine if there was substantial evidence to support such an association between the VDR polymorphisms and DD. METHODS: PubMed, Embase, and Science Direct databases were searched for studies that investigated associations of the FokI (rs2228570, rs10735810), and ApaI (rs7975253) polymorphisms of the VDR gene with DD. From the extracted genotype data from 14 publications, we estimated risk (odds ratio [OR] with 95% confidence intervals). RESULTS: Overall associations of FokI with DD were absent (OR 0.96-1.04, p = 0.73-0.95) with heterogeneity in the dominant and codominant models (pheteroegeneity <0.10, I2 = 47-57%). Post-outlier pooled effects yielded dominant significance indicating reduced risk (OR 0.77, p = 0.01) with concomitant zero heterogeneity (I2 = 0%). ApaI effects pointed to reduced risks, with overall dominant significance (OR 0.69, p = 0.04) and Asian subgroup nonsignificance (OR 0.75-0.93, p = 0.17-0.74). In FokI, Non-Hispanic Caucasians (OR 0.77, p = 0.01) and males (OR 0.36-0.66, p = 0.001-0.04) were protected but not Hispanic Caucasians (OR 1.39-1.85, p = 0.006-0.05) and females (OR 1.72, p = 0.05). Tests of interaction between the genders highlighted female susceptibility and male protection (p = 0.001-0.005). Zero heterogeneity (I2 = 0%) is a key strength of these significant effects. CONCLUSION: This meta-analysis confirmed the protective role of the ApaI polymorphism, however, susceptibility and protective effects of the FokI polymorphism may be ethnic and gender specific.

Analysis of FokI polymorphism of vitamin D receptor gene in intervertebral disc degeneration.

AIM: We have hypothesized a possible relationship between disc degeneration (DD) and VDR FokI/T2C polymorphism. METHODS: A case-control study was performed comprising 121 Brazilian patients with confirmed DD by nuclear magnetic resonance and a control group consisting of 131 healthy patients without a history of disc cysts of the lumbar spine. Detection of VDR FokI/T2C polymorphism was performed using restriction fragment length polymorphism-polymerase chain reaction. The chi-square test was used to compare allele and genotype frequencies between groups, and a p-value of <0.05 was considered statistically significant. RESULTS: The results disclosed statistical difference between allele distribution among cases and controls (p=0.025, odds ratio=1.58, confidence interval=1.07-2.32) considering VDR FokI/T2C polymorphism. CONCLUSION: The results showed a positive association between VDR FokI/T2C polymorphism and DD in Brazilian patients tested.

MTHFR polymorphisms C677T and A1298C and associations with IVF outcomes in Brazilian women.

The aim of this study was to investigate the association between MTHFR gene polymorphisms and IVF outcomes in Brazilian women undergoing assisted reproduction treatment. A prospective study was conducted in the Human Reproduction Department at the ABC University School of Medicine and the Ideia Fertility Institute between December 2010 and April 2012. The patient population was 82 women undergoing assisted reproduction cycles. The MTHFR polymorphisms C677T and A1298C were evaluated and compared with laboratory results and pregnancy rates. The C677T variant was associated with proportions of mature (P=0.006) and immature (P=0.003) oocytes whereas the A1298C variant was associated with number of oocytes retrieved (P=0.044). The polymorphisms, whether alone or in combination, were not associated with normal fertilization, good-quality embryo or clinical pregnancy rates. This study suggests that the number and maturity of oocytes retrieved may be related to the MTHFR polymorphisms C677T and A1298C. It is believed that folate has a crucial function in human reproduction and that folate deficiency can compromise the function of the metabolic pathways it is involved in, leading to an accumulation of homocysteine. The gene MTHFR encodes the 5-MTHFR enzyme, which is involved in folate metabolism, and C677T/A1298C polymorphisms of this gene are related to decreased enzyme activity and consequent changes in homocysteine concentration. Folate deficiency and hyperhomocysteinaemia can also compromise fertility and lead to pregnancy complications by affecting the development of oocytes, preparation of endometrial receptivity, implantation of the embryo and pregnancy. In folliculogenesis, hyperhomocysteinaemia can activate apoptosis, leading to follicular atresia and affecting the maturity of oocytes and the quality of embryos cultured in vitro. This study was performed to investigate the association between MTHFR polymorphisms and IVF outcomes in women undergoing assisted reproduction treatment.

There is no relationship between Paraoxonase serum level activity in women with endometriosis and the stage of the disease: an observational study.

BACKGROUND: Endometriosis is a chronic condition whose pathophysiology is unknown, but there is evidence suggesting a link with oxidative stress. Paraoxonase is a serum enzyme which circulates associated with high-density lipoprotein (HDL). It acts protecting HDL and LDL of lipid peroxidation. We aimed to compare the serum levels of PON-1 activity in women with endometriosis in different stages of the disease (minimal/mild and moderate/severe). METHODS: 80 infertile women with endometriosis diagnosed by laparoscopy/laparotomy with histologic confirmation of the disease were divided according to the American Society for Reproductive Medicine classification in minimal/mild (n = 33) and moderate/severe (n = 47) cases. Paraoxonase activity and arilesterase activity were measured by spectrophotometry. Body mass index and fasting glucose levels were also determined. RESULTS: The paraoxonase activity were 191.29 ± 22.41 U/l in women with minimal/mild endometriosis and 224.85 ± 21.50 U/l in women with moderate/severe disease (P = 0.274). Considering arilesterase level, the results showed 89.82 ± 4.61 U/l in women with minimal/mild endometriosis and 90.78 ± 3.43 U/l in moderate/severe disease (P = 0.888). CONCLUSIONS: Evidence of lower paraoxonase activity in women with endometriosis was not found in this study. Besides, no difference was found considering minimal/mild or moderate/severe endometriosis.

Genetic aspects of premature ovarian failure: a literature review.

BACKGROUND: The diagnosis of premature ovarian failure (POF) is based on the finding of amenorrhea before the age of 40 years associated with follicle-stimulating hormone levels in the menopausal range. It is a heterogeneous disorder affecting approximately 1% of women <40 years, 1:10,000 women by age 20 years and 1:1,000 women by age 30 years. POF is generally characterized by low levels of gonadal hormones (estrogens and inhibins) and high levels of gonadotropins (LH and FSH) (hypergonadotropic amenorrhea). METHODS: Review of significant articles regarding genetic causes that are associated with POF. RESULTS: Heterogeneity of POF is reflected by a variety of possible causes, including autoimmunity, toxics, drugs, as well as genetic defects. Changes at a single autosomal locus and many X-linked loci have been implicated in women with POF. X chromosome abnormalities (e.g., Turner syndrome) represent the major cause of primary amenorrhea associated with ovarian dysgenesis. Many genes have been involved in POF development, among them BMP15, FMR1, FMR2, LHR, FSHR, INHA, FOXL2, FOXO3, ERα, SF1, ERß and CYP19A1 genes. CONCLUSION: Despite the description of several candidate genes, the cause of POF remains undetermined in the vast majority of cases.