Comparison of sperm PAWP and chromatin status between normozospermic and ab-normozoospermic men

Background and aims: Sperm postacrosomal WW binding protein (PAWP) was expressed during spermiogenesis and recently introduced as one of sperm factors involved in oocyte activation. Therefore, the aim of this study was to compare sperm PAWP and chromatin status between individuals with normal (normozospermia) and abnormal (ab-normozoospermia) sperm parameters. Results: Significant differences were observed in sperm parameters such as sperm concentration, motility, morphology between men with normozospermia and ab-normozoospermia. Mean percentage of sperm PAWP was significantly lower in ab-normozoospermic men compared to normozospermic men. In addition, mean percentage of spermatozoa with DNA damage and protamine deficiency were significantly higher in ab-normozoospermic men compared to normozospermic men. In addition, significant associations were observed between percentages of sperm PAWP with sperm parameters. Conclusion: The results of the current study show that in men with ab-normozoospermia, sperm functional tests such as DNA damage, protamine deficiency, and also percentage of sperm factor (PAWP) related to oocyte activation were in range of abnormality. Therefore, assessment of these tests can be efficient in the decision of treatment in infertile men

Improvement of sperm function, chromatin damage, and oxidative damage by N-Acetyl cysteine in varicocelized rats model

Introduction: N-Acetylcysteine (NAC), an acetylated form of the amino acid cysteine and precursor of reduced glutathione, plays important roles in a multitude of cellular processes, such as oxidative damage and detoxification of many electrophiles. Considering the pathophysiology of oxidative stress induced infertility in varicocele, we aimed to investigate the effect of NAC on semen analysis parameters (light microscopy), chromatin structure (aniline blue and acridine orange staining), and lipid peroxidation (BODIPY probe) in varicocelized rats.Methods: In this experimental study, varicocelizing surgery was carried out on 30 Wistar rats. Ten of them were sacrificed after two months (one round spermatogenesis), together with control rats (n=10) and sham operated rats (n=10), to verify the varicocele model. Out of the remaining twenty varicocelized rats, ten received NAC while ten were treated with water (control group) for two months.Results: All the investigational parameters (sperm parameters, chromatin integrity, and lipid peroxidation) severely worsened 2 and 4 months after surgical varicocele. The administration of NAC for two months significantly improved all the investigational parameters as compared to control rats at four months (p<0.05).Conclusion: The supplementation of varicocelized rats with NAC was effective in antagonizing the damage as well as in preserving testicular structure and spermatogenetic function. These effects are likely to occur also in clinical varicocele

Effects of assisted oocyte activation with calcium- ionophore and strontium chloride on in vitro ICSI outcomes

Objective(s): Failed fertilization after intra-cytoplasmic sperm injection (ICSI) is mainly attributed to failed oocyte activation and can be overcome by artificial oocyte activation (AOA). The present study aims to compare in vitro outcomes of ICSI following two different assisted oocyte activation chemical procedures (SrCl2 and Ionomycin) in sibling oocytes of ICSI candidates.Materials and Methods: From March 2015 until February 2016, 105 infertile men with 99–100% abnormal sperm morphology, irrespective of sperm motility, concentration, or origin (semen or testicular) were included in this study. Out of these, 66 couples accepted to be included in the study group (Ionomycin/ SrCl2) and 39 couples requested routine AOA procedure (Ionomycin) as external control group. Primary outcomes of this study (fertilization, embryo quality, and post-implantation development) were compared between these groups.Results: Significantly higher oocyte activation (67.90±3.6% vs. 51.16±3.6%, P=0.004) and fertilization (65.23±3.63% vs. 49.65±3.63%, P=0.008) rates were observed in sibling oocytes treated with Ionomycin in comparison to the SrCl2 sibling group. Percentage of top quality embryos was insignificantly higher in SrCl2 groups compared to the Ionomycin group (29.90±4.27 vs. 20.65±4.05%, P=0.26).Conclusion: Ionomycin may be superior to SrCl2 for inducing oocyte activation. However, SrCl2 may be a more efficient means to support the development of better quality embryos following ICSI

Role of Endoplasmic Reticulum Stress in The Male Reproductive System

Testicular dysfunction, whether linked to varicocele, obesity, diabetes, aging, inflammation, or lifestyle or environmentalissues, is frequently accompanied by an accumulation of unfolded or misfolded proteins, indicating impaired endoplasmicreticulum (ER) function. In this review, we examined the Google Scholar, Scopus and PubMed databases (from 2011to 2022) to support the association of ER stress with defective spermatogenesis in animal models and humans. ERstress, whether in its pro-survival or pro-apoptotic aspect, appears to be closely linked to each studied situation.Several studies have demonstrated a significant increase in oxidative stress (OS) levels in infertile men compared tofertile individuals, which is associated with poor spermatogenesis quality. OS is likely the result of the interplay betweenER stress and spermatogenesis defects. These findings suggest that therapeutic strategies aimed at mitigating bothER stress and OS could be of interest in restoring male reproductive function

Effects of Streptozotocin Induced Diabetes on One-Carbon Cycle and Sperm Function

Objective: Diabetic men suffer an increased risk of infertility associated with signs of oxidative damage and decreasedmethylation in sperm pointing to a deficit of the one-carbon cycle (1CC). We aimed to investigate this deficit using micemodels (type 1 and 2) of streptozotocin-induced diabetes.Materials and Methods: In this experimental study, 50 male mice, aged eight weeks, were divided randomly intofour groups: sham, control, type 1 diabetes mellitus (DM1), and DM2. The DM1 group was fed a normal diet (ND) foreight weeks, followed by five consecutive days of intraperitoneal administration of Streptozotocin (STZ, 50 mg/kg bodyweight). The DM2 group was fed a high-fat diet (HFD) for eight weeks, followed by a single intraperitoneal injectionof STZ (100 mg/kg). After twelve weeks, all the mice were euthanized, and study parameters assessed. In the shamgroup, citrate buffer as an STZ solvent was injected.Results: Both types of diabetic animals had serious impairment of spermatogenesis backed by increased DNA damage(P=0.000) and decreased chromatin methylation (percent: P=0.019; intensity: P=0.001) and maturation (P=0.000).The 1CC was deeply disturbed with increased homocysteine (P=0.000) and decreased availability of carbon units[methionine (P=0.000), serine (P=0.088), folate (P=0.016), B12 (P=0.025)] to feed methylations.Conclusion: We have observed a distinct impairment of 1CC within the testes of individuals with diabetes. Wespeculate that this impairment may be linked to inadequate intracellular glucose and diminished carbon unit supplyassociated with diabetes. As a result, interventions focusing on enhancing glucose uptake into sperm cells and providingsupplementary methyl donors have the potential to improve fertility issues in diabetic patients. However, additionalclinical testing is required to validate these hypotheses

Increased de novo DNA methylation enzymes in sperm of individuals with varicocele

Objective: Chronic genital heat-stress associated with varicocele leads to DNA hypo-methylation of spermatozoa. The objective of this study was comparing level of DNA methyl-transferases (DNMTs) in sperm of men suffering varicocele with fertile individuals. Materials and Methods: In this case-control study, semen samples were obtained from 35 infertile men with varicocele (grade II or III) and 26 fertile men. Sperm parameters were assessed according to World Health Organization (WHO) protocol. DNMTs enzymes level were assessed by flow cytometer and fluorescence microscope. mRNAs expression of these DNMTs were also assessed by real-time reverse transcription polymerase chain reaction (RT-PCR). Results: DNMT1 and DNMT3A proteins were mainly localized in equatorial and mid-piece regions of sperm head, respectively, while DNMT3B protein appeared to be localized mainly in equatorial and anterior regions of sperm head. In contrast to DNMT1, expression and percentage of DNMT3A and DNMT3B at RNA and protein levels were significantly higher in the varicocele group compared to the fertile group (P<0.05). In addition, significant correlations were found between sperm concentration and motility as well as DNMT1 and DNMT3B proteins levels in the infertile individuals with varicocele (P<0.05). Additionally, significant correlations were observed between abnormal sperm morphology with DNMTs proteins in the infertile individuals with varicocele. Conclusion: Unlike DNMT1, which is involved in maintenance of DNA methylation at both RNA and protein levels, expression of de novo methylation enzymes (DNMT3A and DNMT3B) at both levels were increased in the varicocele group compared to the fertile group. Based on literature, this increase might be due to the dual roles played by DNMT3A and DNMT3B, as methyl-transferases in normal condition as well as dehydroxymethylases in stress condition, like varicocele. Although, this hypothesis needs further validation

Evaluation of the leptin receptor in human spermatozoa

<p>Abstract</p> <p>Background</p> <p>Leptin, a 167 amino acid peptide hormone, profoundly effects reproduction exerting its biological effects via interaction with the leptin receptor (ObR) which is widely expressed on peripheral tissues. In this study, we have attempted to assess leptin receptor expression in the spermatozoa of fertile males and those diagnosed with male factor infertility; both at the mRNA or protein levels.</p> <p>Methods</p> <p>Semen samples were collected from fertile males and individuals with male factor infertility. In order to evaluate leptin receptor expression several techniques were utilized, including: reverse transcriptase-polymerase chain reaction (RT-PCR), immunostaining, flow cytometry, and western blotting. Mononuclear cells isolated from volunteers' peripheral blood were used as positive controls for leptin receptor expression.</p> <p>Results</p> <p>leptin receptor was noted on mononuclear cells but we were unable to detect this receptor on spermatozoa at the protein level. Leptin receptor expression was detected on peripheral blood mononuclear cells (PBMCs) as positive controls; however it was not detectable on the spermatozoa of both groups by immunofluorescence microscopy or flow cytometry. Furthermore, positive expression of the ObR long isoform as assessed by RT-PCR was observed in the sperm of only four cases, whereas expression of beta-Actin, a house keeping gene, and HspA2, a testis specific gene, was present in all cases.</p> <p>Conclusion</p> <p>The long isoform of leptin receptor may not be present on human sperm. Species difference may be accounted for diverse reproductive physiology which depends on metabolic requirement. Leptin receptor expression at the mRNA level in some individuals may be related to contamination by other cells in semen.</p

Study of Sperm Chromatin in Infertile Men with Globozoospermia: A Systematic Review Article

Background and Aim: Globozoospermia is a severe sperm morphological abnormality in men that characterized by round-headed spermatozoa with low or absence acrosome structure in their sperm samples. In these men, high level of DNA damage and abnormal chromatin packaging also were reported. These deficiencies can consider as the main etiologies of infertility in these infertile men. The aim of this article is to study the sperm chromatin structure in infertile men with globozoospermia. Materials and Methods: In this systematic review article, 77 articles related to protamine deficiency, DNA damage, aneuploidy in globozoospermic men were collected via data bases such as PubMed, Google Scholar, Scopus since 1971-2017. Ethical Considerations: This study with research ethics code IR.ACECR.ROYAN.REC.1396.204 have been approved at research ethics committee of Royan Institute. Findings: Mean percentage of sperm DNA fragmentation and protamine deficiency were significantly higher in infertile men with globozoospermia compared to fertile men. While, the results of chromosome aneuploidy were controversial in infertile men with globozoospermia within studies. Conclusion: In addition to abnormal acrosome formation, as main etiology of failed fertilization, in infertile men with globozoospermia, high level of sperm abnormal chromatin packaging and DNA damage can be also involved in this phenomenon. Therefore, antioxidant therapy before intra-cytoplasmic sperm injection technique were suggested for these individuals to minimize sperm chromatin damage

Comparison of sperm PLCζ protein and DNA damage between fertile and infertile men

Introduction: Sperm-specific phospholipase C zeta (PLC&zeta;) protein is expressed during spermatogenesis and plays a main role during oocyte activation. In this study, the expression of sperm PLC&zeta; protein and DNA damage in fertile and infertile men was assessed. Methods: In this case-control study, semen samples were collected from 15 fertile and 10 infertile men candidated for intra-cytoplasmic sperm injection (ICSI). Sperm parameters, the expression of PLC&zeta; protein, and DNA damage were assessed by the World Health Organization (2010) protocol, Western Blot, and TUNEL assay, respectively. Results: The quality of sperm parameters were significantly lower in the infertile men compared with the fertile men. In addition, the expression of PLC&zeta; protein was significantly lower, and percentage of sperm DNA damage were significantly higher in infertile men than fertile men.&nbsp; Conclusion: Our results clearly showed that low or absence expression of PLC&zeta; and sperm DNA damage could be considered as factors involved in failed fertilization in these infertile men. Therefore, the evaluation of some tests such as PLC&zeta; protein and chromatin tests to assess fertilization potential of a semen sample for infertile men are recommended