Angiogenesis is an essential process for proper functioning of the female reproductive system and for successful pregnancy realization. The multitude of factors required for physiological angiogenesis and the complexity of regulation of their temporal-spatial activities contribute to aberrations in human fertilization and pregnancy outcomes. In this study, we reviewed the current knowledge of the temporal expression patterns, functions, and regulatory mechanisms of angiogenic factors during foliculogenesis, early implantation/placentation and embryo development, as well as recurrent spontaneous abortions. Angiogenic factors including vascular endothelial growth factors and angiopoietins have documented roles in the development of primordial follicles into mature antral follicles. They also participate in decidualization, which is accompanied by the creation of an extensive network of vessels in the stromal bed that support the growth of the embryo and the placenta, and maintain early pregnancy. During placentation angiogenic and angiomodulatory cytokines, T and B lymphocytes and macrophages affect angiogenesis in a context-dependent manner. Defects in angiogenesis at the maternal-fetal interface contribute to miscarriage in humans. The establishment of more polymorphisms in the genes involved in angiogenesis/vasculogenesis, and their pathological phenotype and expression could give opportunities for prediction, creating a therapeutic strategy, and treatment of diseases related to female reproductive health and problematic conception.
1 December 2015 in Balkan Journal of Medical Genetics
Epigenetic changes, in particular DNA methylation processes, play a role in the pathogenesis and progression of type 2 diabetes mellitus (T2DM) linking genetic and environmental factors. To clarify this role, we have analyzed in patients with different duration of T2DM: (i) expression levels of methyl-CpG-binding domain protein 2 (MBD2) as marker of DNA methylation, and ii) methylation changes in 22 genes connected to cellular stress and toxicity. We have analyzedMBD2mRNA expression levels in16 patients and 12 controls and the methylation status of stress and toxicity genes in four DNA pools: (i) controls; (ii) newly-diagnosed T2DM patients; (iii) patients with T2DM duration of 5 years. TheMBD2expression levels were 10.4-times increased on average in T2DM patients compared to controls. Consistent increase in DNA methylation fraction with the increase in T2DM duration was observed inPrdx2andSCARA3genes, connected to oxidative stress protection and inBRCA1andTp53tumor-suppressor genes. In conclusion, increasedMBD2expression in patients indicated general dysregulation of DNA methylation in T2DM. The elevated methylation ofPrdx2andSCARA3genes suggests disturbance in oxidative stress protection in T2DM. The increased methylation ofBRCA1andTp53genes unraveled an epigenetic cause for T2DM related increase in cancer risk.
10 March 2023 in Biotechnology & Biotechnological Equipment
To study two major molecular alterations in spontaneous abortions (SA) with unexplained etiology - fetal genomic anomalies and the endometrial expression of main angiogenic factors VEGFA/VEGFR2 and chemokines SDF-1/CXCR4. Whole genome copy number analysis by arrayCGH or Next Generation Sequencing (NGS) was applied for detection of fetal genomic imbalances. The abortive decidua of SA without fetal aneuploidies was further investigated for expression levels of the abovementioned factors using real time PCR analysis. A total of 30 abortive materials were collected from spontaneous abortions after exclusion of known predisposing factors. In 21 of 30 spontaneous abortions (70%), genomic anomalies were discovered by whole genome copy number analysis. Numerical anomalies were detected in 90% of aberrant cases, and in 10% - structural aberrations were revealed. An increased expression for essential factors of angiogenesis was identified in spontaneous abortions' tissues - 3.44 times for VEGFA and 10.29 times for VEGFR2. We found an average of 14 times increase in the expression levels of SDF-1 and 3.21 times for its receptor CXCR4. We could suggest the occurrence of increased angiogenesis in SA without fetal aneuploidies, compared to the control tissues, which could lead to increased oxidative stress and fetal loss.
Congenital muscle dystrophies (CMD) are genetically and clinically heterogeneous hereditary myopathies mainly with autosomal recessive type of inheritance. The most common form worldwide is considered to be merosin-deficient muscle dystrophy type 1A, called MDC1A (due to laminin-α2 defects as a result of LAMA2 gene mutation), accounting for 30-40% of total cases of CMD. The exact molecular and clinical diagnoses, respectively, are a prerequisite for the most effective treatment; sometimes orphan drugs exist for some rare diseases. One of such drugs is Tarix, which was FDA approved and announced in 2016 for treatment of MDC1A. Here we present a patient diagnosed postmortem as having early-onset LAMA2-related muscular dystrophy as a result of mutations in LAMA2, identified by Sanger sequencing in his parents: a novel nonsense mutation c.4452T>A in exon 31, identified in the mother, and a known pathogenic nonsense mutation c.2901C>A in exon 21, detected in the father. The truncating nature of both nonsense mutations made the clinical presentation severe and the outcome fatal. Genetic analysis in such cases of muscle dystrophy is of utmost impact, because it makes the correct diagnosis with at least some specific options for treatment, makes the prognosis depending on the severity of mutation discovered, determines reproductive risk, and offers prophylaxis in the family by means of prenatal or preimplantation diagnostics.
The aim of our study was to determine the type and frequency of chromosomal aberrations and polymorphisms in men with different degrees of spermatogenic failure in comparison to men with normozoospermia, in order to find correlations between cytogenetic findings and the abnormal results of semen analysis. In our study, we performed cytogenetic analysis in 901 infertile men, divided into five groups according to semen analysis—normozoospermia (86), asthenozoospermia (394), oligoasthenozoospermia (182), severe male factor (100), and azoospermia (139). The frequency of polymorphisms was similar in all groups (11–16%, without significant differences). The frequency of numerical and structural aberrations increases with the degree of the spermatogenic failure (3.5% in normozoospermia, 5.6% in asthenozoospermia, 9.8% in oligoasthenozoospermia, 9% in severe male factor, and 13.5% in azoospermia). We found a significantly higher incidence of numerical chromosomal aberrations in severe male factor (7%) and azoospermia (9.3%). Oligoasthenozoospermia occured in 45% of cases with translocation, compared to 20% in the group with a normal karyotype. We revealed that chromosomal translocations are tightly associated with oligoasthenozoospermia, whereas numerical chromosomal aberrations—with severe male factor and azoospermia. The impact of chromosome polymorphisms on male infertility should be studied in greater detail.