Concentrations of homocysteine in follicular fluid and embryo quality and oocyte maturity in infertile women: a prospective cohort

Homocysteine is one of the components of follicular fluid (FF), so that any disruptions in its concentration may affect oocyte development. The aim of this study was to determine the relationship between FF homocysteine concentration and embryo quality, oocyte maturity, and pregnancy rate. Oocytes and embryos of 44 infertile women were categorised into different groups based on their maturity and quality, respectively. FF homocysteine levels, oocyte maturity, embryo quality, and pregnancy status were measured. A significant association was observed between the levels of FF homocysteine ​and oocyte maturation rate (p = .00). The concentration of FF homocysteine was higher than 9.8 µm/L in women with oocyte maturation < 80%. Most of the good quality embryos belonged to homocysteine levels < 9.8 µm/L. Decreased FF homocysteine concentrations can significantly improve the oocyte maturation rate and embryo quality. Aging may be an indirect factor contributing to decreased embryo quality and oocyte maturation through increasing FF homocysteine levels.IMPACT STATEMENTWhat is already known on this subject? It has been demonstrated that homocysteine is one of the components of follicular fluid (FF), but no information is available about the link between its concentration in FF and oocyte development.What do the results of this study add? The data indicated that decreased FF homocysteine concentrations at a younger age may remarkably improve the oocyte maturity and embryo quality of infertile patients undergoing assisted reproductive treatment (ART).What are the implications of these findings for clinical practice and/or further research? Based on the findings and considering the ease of measuring serum homocysteine and its direct correlation with FF homocysteine, homocysteine level measurement is recommended in patients who are candidates for infertility treatment in order to estimate oocyte maturation rate, embryo quality, and ART outcomes. Future studies are suggested to investigate patients with PCOS, endometriosis, and male factor infertility.

Sperm parameters, DNA integrity, and protamine expression in patients with type II diabetes mellitus

Diabetes Mellitus (DM) is the most common endocrine disorder affecting many human physiological systems and tissues, including the reproductive organs in men. The age of individuals suffering from this disease has been falling rapidly in recent years. This study compared the effect of DM on sperm parameters, chromatin quality, and apoptosis, as well as the expression profile of protamine genes in men with and without DM using molecular and cytochemical assays. Sixty semen samples from the control group (N = 30) and case group (N = 30) were collected. There was a significant decrease in the percentages of sperm parameters in cases versus the controls (p˂0.05). Despite significantly higher percentages detected in spermatozoa with AB⁺, CMA3⁺, and TUNEL⁺, no change was demonstrated regarding protamines mRNA levels, as well as the P1/P2 ratios in cases in comparison with controls. In contrast, significant positive correlations were found between the quantity of P1 and P2 transcripts (r = 0.944, p < .001). The data indicated that DM not only caused a decrease in the quality of sperm parameters but also affected the sperm maturation process by increasing the substantial implications in the sperm DNA/chromatin levels of DM patients.IMPACT STATEMENTWhat is already known on this subject? Diabetes Mellitus (DM) is a chronic metabolic disorder affecting many human physiological systems and tissues, including the reproductive organs in men. The age of individuals suffering from this disease has been falling rapidly in recent years.What do the results of this study add? We found that DM not only caused a decrease in the quality of the sperm parameters, including motility and concentration, and an increase in morphological abnormalities but also affected the sperm maturation process by increasing the substantial implications in sperm DNA/chromatin levels of DM patients. Despite there being no significant difference in the mRNA levels of protamines between the two groups, our findings showed a positive correlation between the mRNA levels of P1 and progressive sperm motility.What are the implications of these findings for clinical practice and/or further research? Based on the results of this study, chromatin and DNA assessments can have important implications for increasing fertility, as complementary tests, in combination with routine laboratory tests. Since sperm standard parameters are not capable of examining the condition of the sperm nucleus, men with abnormal sperm DNA can also have normal spermatogram, and diabetes is prevalent in reproductive age.

Sperm chromatin quality and DNA integrity in partial versus total globozoospermia

Globozoospermia is a severe form of teratozoospermia with low incidence in infertile patients, considered as one of the important causes of male infertility. The objective was to investigate the chromatin/DNA integrity as well as apoptosis in ejaculated spermatozoa of cases with partial or total globozoospermia. Fifty-seven semen samples were divided into three groups of partial globozoospermia (n = 17), total globozoospermia (n = 10) and normozoospermia (control; n = 30). Sperm chromatin condensation, DNA integrity and apoptosis were assessed using cytochemical assays. The results showed significant differences in sperm parameters of count and motility between two case groups versus controls. The percentages of spermatozoa with abnormal chromatin packaging and protamine deficiency were significantly higher in total and partial globozoospermic men compared to normozoospermic samples. Also, the rates of TUNEL-positive spermatozoa were significantly increased in both globozoospermic cases with respect to the control (18.3 ± 10.1 and 12.3 ± 9.2 versus 5.9 ± 3 respectively). However, no significant differences were noticed between two subgroups of patients with regard to sperm DNA denaturation, DNA fragmentation and apoptosis. Abnormal chromatin packaging, DNA damage and apoptosis were significantly higher in cases than controls. The sperm chromatin/DNA anomalies may be considered as one of the main aetiology of ART failure in globozoospermic patients.