Seminal miRNA Relationship with Apoptotic Markers and Oxidative Stress in Infertile Men with Varicocele

Identification and functional prediction of miRNAs that regulate ROS levels in dielectric barrier discharge plasma-treated boar spermatozoa

Dielectric barrier discharge (DBD) plasma regulates the levels of reactive oxygen species (ROS), which are critical for sperm quality. MicroRNAs (miRNAs) are non-coding single-stranded RNA molecules encoded by endogenous genes, which regulate post-transcriptional gene expression in animals. At present, it is unknown whether DBD plasma can regulate sperm ROS levels through miRNAs. To further understand the regulatory mechanism of DBD plasma on sperm ROS levels, miRNAs in fresh boar spermatozoa were detected using Illumina deep sequencing technology. We found that 25 known miRNAs and 50 novel miRNAs were significantly upregulated, and 14 known miRNAs and 74 novel miRNAs were significantly downregulated in DBD plasma-treated spermatozoa. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that target genes of differentially expressed miRNAs were involved in many activities and pathways associated with antioxidants. We verified that DBD plasma significantly increased boar sperm quality and reduced ROS levels. These results suggest that DBD plasma can improve sperm quality by regulating ROS levels via miRNAs. Our findings provide a potential strategy to improve sperm quality through miRNA-targeted regulation of ROS, which helps to increase male reproduction and protect cryopreserved semen in clinical practice.

Behind the Genetics: The Role of Epigenetics in Infertility-Related Testicular Dysfunction

In recent decades, we have witnessed a progressive decline in male fertility. This is partly related to the increased prevalence of chronic diseases (e.g., obesity and diabetes mellitus) and risky lifestyle behaviors. These conditions alter male fertility through various non-genetic mechanisms. However, there is increasing evidence that they are also capable of causing sperm epigenetic alterations, which, in turn, can cause infertility. Furthermore, these modifications could be transmitted to offspring, altering their general and reproductive health. Therefore, these epigenetic modifications could represent one of the causes of the progressive decline in sperm count recorded in recent decades. This review focuses on highlighting epigenetic modifications at the sperm level induced by non-genetic causes of infertility. In detail, the effects on DNA methylation, histone modifications, and the expression profiles of non-coding RNAs are evaluated. Finally, a focus on the risk of transgenerational inheritance is presented. Our narrative review aims to demonstrate how certain conditions can alter gene expression, potentially leading to the transmission of anomalies to future generations. It emphasizes the importance of the early detection and treatment of reversible conditions (such as obesity and varicocele) and the modification of risky lifestyle behaviors. Addressing these issues is crucial for individual health, in preserving fertility, and in ensuring the well-being of future generations.

Effects of Slow Freezing and Vitrification of Human Semen on Post-Thaw Semen Quality and miRNA Expression

Semen cryopreservation has played an important role in medically assisted reproduction for decades. In addition to preserving male fertility, it is sometimes used for overcoming logistical issues. Despite its proven clinical usability and safety, there is a lack of knowledge of how it affects spermatozoa at the molecular level, especially in terms of non-coding RNAs. Therefore, we conducted this study, where we compared slow freezing and vitrification of good- and poor-quality human semen samples by analyzing conventional sperm quality parameters, performing functional tests and analyzing the expression of miRNAs. The results revealed that cryopreservation of normozoospermic samples does not alter the maturity of spermatozoa (protamine staining, hyaluronan binding), although cryopreservation can increase sperm DNA fragmentation and lower motility. On a molecular level, we revealed that in both types of cryopreservation, miRNAs from spermatozoa are significantly overexpressed compared to those in the native semen of normozoospermic patients, but in oligozoospermic samples, this effect is observed only after vitrification. Moreover, we show that expression of selected miRNAs is mostly overexpressed in native oligozoospermic samples compared to normozoospermic samples. Conversely, when vitrified normozoospermic and oligozoospermic samples were compared, we determined that only miR-99b-5p was significantly overexpressed in oligozoospermic sperm samples, and when comparing slow freezing, only miR-15b-5p and miR-34b-3p were significantly under-expressed in oligozoospermic sperm samples. Therefore, our results imply that cryopreservation of normozoospermic sperm samples can modulate miRNA expression profiles in spermatozoa to become comparable to those in oligozoospermic samples.

MicroRNAs in Male Fertility

Around 50% of all occurrences of infertility are attributable to the male factor, which is a significant global public health concern. There are numerous circumstances that might interfere with spermatogenesis and cause the body to produce abnormal sperm. While evaluating sperm, the count, the speed at which they migrate, and their appearance are the three primary characteristics that are analyzed. MicroRNAs, also known as miRNAs, are present in all physiological fluids and tissues. They participate in both physiological and pathological processes. Researches have demonstrated that the expression of microRNA genes differs in infertile men. These genes regulate spermatogenesis at various stages and in several male reproductive cells. Hence, microRNAs have the potential to act as useful indicators in the diagnosis and treatment of male infertility and other diseases affecting male reproduction. Despite this, additional research is necessary to determine the precise miRNA regulation mechanisms.

Impacts of non-coding RNAs in the pathogenesis of varicocele

Two classes of non-coding RNAs, namely lncRNAs and miRNAs have been reported to be involved in the pathogenesis of varicocele. MIR210HG, MLLT4-AS1, gadd7, and SLC7A11-AS1 are among lncRNAs whose expression has been changed in patients with varicocele in association with the sperm quality. Animal studies have also suggested contribution of NONRATG001060, NONRATG002949, NONRATG013271, NONRATG027523 and NONRATG023747 lncRNAs in this pathology. Meanwhile, expression of some miRNAs, such as miR-210-3p, miR-21, miR-34a, miR-122a, miR-181a, miR-34c and miR-192a has been altered in this condition. Some of these transcripts have the potential to predict the sperm quality. We summarize the impacts of lncRNAs and miRNAs in the pathogenesis of varicocele.

MicroRNAs in spermatogenesis dysfunction and male infertility: clinical phenotypes, mechanisms and potential diagnostic biomarkers

Infertility affects approximately 10-15% of couples worldwide who are attempting to conceive, with male infertility accounting for 50% of infertility cases. Male infertility is related to various factors such as hormone imbalance, urogenital diseases, environmental factors, and genetic factors. Owing to its relationship with genetic factors, male infertility cannot be diagnosed through routine examination in most cases, and is clinically called 'idiopathic male infertility.' Recent studies have provided evidence that microRNAs (miRNAs) are expressed in a cell-or stage-specific manner during spermatogenesis. This review focuses on the role of miRNAs in male infertility and spermatogenesis. Data were collected from published studies that investigated the effects of miRNAs on spermatogenesis, sperm quality and quantity, fertilization, embryo development, and assisted reproductive technology (ART) outcomes. Based on the findings of these studies, we summarize the targets of miRNAs and the resulting functional effects that occur due to changes in miRNA expression at various stages of spermatogenesis, including undifferentiated and differentiating spermatogonia, spermatocytes, spermatids, and Sertoli cells (SCs). In addition, we discuss potential markers for diagnosing male infertility and predicting the varicocele grade, surgical outcomes, ART outcomes, and sperm retrieval rates in patients with non-obstructive azoospermia (NOA).

Normospermic Patients Infected With Ureaplasma parvum: Role of Dysregulated miR-122-5p, miR-34c-5, and miR-141-3p

Background

Ureaplasma parvum (UP) is a causative agent of non-gonococcal urethritis, involved in the pathogenesis of prostatitis and epididymitis, and it could impair human fertility. Although UP infection is a frequent cause of male infertility the study evidence assessing their prevalence and the association in patients with infertility is still scarce. The molecular processes leading to defects in spermatozoa quality are not completely investigated. MicroRNAs (miRNAs) have been extensively reported as gene regulatory molecules on post-transcriptional levels involved in various biological processes such as gametogenesis, embryogenesis, and the quality of sperm, oocyte, and embryos.

Methods

Therefore, the study design was to demonstrate that miRNAs in body fluids like sperm could be utilized as non-invasive diagnostic biomarkers for pathological and physiological conditions such as infertility. A post-hoc bioinformatics analysis was carried out to predict the pathways modulated by the miRNAs dysregulated in the differently motile spermatozoa.

Results

Here it is shown that normospermic patients infected by UP had spermatozoa with increased quantity of superoxide anions, reduced expression of miR-122-5p, miR-34c-5, and increased miR-141-3p compared with non-infected normospermic patients. This corresponded to a reduction of sperm motility in normospermic infected patients compared with normospermic non-infected ones. A target gene prediction presumed that an essential role of these miRNAs resided in the regulation of lipid kinase activity, accounting for the changes in the constitution of spermatozoa membrane lipids caused by UP.

Conclusions

Altogether, the data underline the influence of UP on epigenetic mechanisms regulating spermatozoa motility.

Surgically retrieved spermatozoa for ICSI cycles in non-azoospermic males with high sperm DNA fragmentation in semen

Intracytoplasmic sperm injection (ICSI) using surgically retrieved spermatozoa outside the classic context of azoospermia has been increasingly used to overcome infertility. The primary indications include high levels of sperm DNA damage in ejaculated spermatozoa and severe oligozoospermia or cryptozoospermia, particularly in couples with ICSI failure for no apparent reason. Current evidence suggests that surgically retrieved spermatozoa for ICSI in the above context improves  outcomes, mainly concerning pregnancy and miscarriage rates. The reasons are not fully understood but may be related to the lower levels of DNA damage in spermatozoa retrieved from the testis compared with ejaculated counterparts. These findings are consistent with the notion that excessive sperm DNA damage  can be a limiting factor responsible for the failure to conceive. Using testicular in preference of low-quality ejaculated spermatozoa bypasses post-testicular sperm DNA damage caused primarily by oxidative stress, thus increasing the likelihood of oocyte fertilization by genomically intact spermatozoa. Despite the overall favorable results, data remain limited, and mainly concern males with confirmed sperm DNA damage in the ejaculate. Additionally, information regarding the health of ICSI offspring resulting from the use of surgically retrieved spermatoa of non-azoospermic males is still lacking. Efforts should be made to improve the male partner's reproductive health for safer ICSI utilization. A comprehensive andrological evaluation aiming to identify and treat the underlying male infertility factor contributing to sperm DNA damage is essential for achieving this goal.

Genetic variants in varicocele-related male infertility: a systematic review and future directions

Genetic association studies (GAS) may have the capability to probe the genetic susceptibility alleles in many disorders. This systemic review aimed to assess whether an association exists between gene(s)/allelic variant(s), and varicocele-related male infertility (VRMI). This review included 19 GAS that investigated 26 genes in 1,826 men with varicocele compared to 2,070 healthy men, and 263 infertile men without varicocele. These studies focussed on candidate genes and relevant variants, with glutathione S-transferase gene being the most frequently studied (n = 5) followed by the nitric oxide synthase 3 (NOS3) gene (n = 3) and the phosphoprotein tyrosine phosphatase 1 gene (n = 2). In one study the genes for NAD(P)H quinone oxidoreductase 1, sperm protamine, human 8-oxoguanine DNA glycosylase 1, methylenetetrahydrofolate reductase, polymerase gamma, heat shock protein 90, mitochondrial DNA, superoxide dismutase 2, transition nuclear protein 1, and transition nuclear protein 2, were assessed. There is no clear indication that any of these polymorphisms are sturdily associated with VRMI. However, three studies established that the polymorphic genotype (GT + TT) for rs1799983 polymorphism of the NOS3 gene is more frequent in varicocele patients. Further endeavours such as standardising reporting, exploring complementary designs, and the use of GWAS technology are justified to help replicate these early findings.

Sperm DNA Fragmentation and Sperm-Borne miRNAs: Molecular Biomarkers of Embryo Development?

The evaluation of morpho-functional sperm characteristics alone is not enough to explain infertility or to predict the outcome of Assisted Reproductive Technologies (ART): more sensitive diagnostic tools are needed in clinical practice. The aim of the present study was to analyze Sperm DNA Fragmentation (SDF) and sperm-borne miR-34c-5p and miR-449b-5p levels in men of couples undergoing ART, in order to investigate any correlations with fertilization rate, embryo quality and development. Male partners (n = 106) were recruited. Semen analysis, SDF evaluation and molecular profiling analysis of miR-34c-5p and miR-449b-5p (in 38 subjects) were performed. Sperm DNA Fragmentation evaluation- a positive correlation between SDF post sperm selection and the percentage of low-quality embryos and a negative correlation with viable embryo were found. SDF > 2.9% increased the risk of obtaining a non-viable embryo by almost 4-fold. Sperm miRNAs profile—we found an association with both miRNAs and sperm concentration, while miR-449b-5p is positively associated with SDF. Moreover, the two miRNAs are positively correlated. Higher levels of miR-34c-5p compared to miR-449b-5p increases by 14-fold the probability of obtaining viable embryos. This study shows that SDF, sperm miR-34c-5p, and miR-449b-5p have a promising role as biomarkers of semen quality and ART outcome.

Key methodological challenges in detecting circulating miRNAs in different biofluids

The technological advancement in diagnostic techniques has immensely improved the capability of predicting disease progression. Yet, there is a great interest in developing newer biomarkers that can enhance disease risk prediction thereby minimising the associated morbidity and mortality. Circulating miRNAs, a non-coding RNA molecule, are critical regulators in the pathophysiology of various complex multifactorial diseases. In recent years, circulating miRNAs have been enormously studied and are considered as an emerging biomarker due to their easy accessibility, stability, and detection by sequence-specific amplification methods. However, there is a distinct lack of consensus regarding the preanalytical factors such as preferred sample selection, methodological aspects, etc that may independently or together influence the detection of circulating miRNAs resulting in erroneous expression profiles. Therefore, the present review makes an attempt to highlight the various pre-analytical and analytical factors that can potentially influence the circulating miRNA levels. Literature on circulating miRNA's stability, processing and quantitation in different biofluids along with the effect of various controllable and uncontrollable factors influencing circulating miRNA expression have been summarised in the current review.

Elucidation of the mechanism of miR‑122‑5p in mediating FOXO3 injury and apoptosis of mouse cochlear hair cells induced by hydrogen peroxide

Unveiling the mechanism of miR-122-5p in the mediation of forkhead box O3 (FOXO3) in regards to cochlear hair cell damage provides an effective solution for the treatment of ear hearing disorders. An oxidative stress model using a mouse cochlear hair cell line (HEI-OC1) was established via hydrogen peroxide (H₂O₂). Then HEI-OC1 cells were transfected with miR-122-5p mimic, miR-122-5p inhibitor, and lentiviral vector FOXO3-WT/MUT. Cell viability and apoptosis rate were determined by MTT assay and flow cytometry. Reactive oxygen species (ROS) were observed by confocal laser scanning microscopy. Bcl-2, Bax, capase-3 and c-caspase-9 levels were quantified by western blot analysis and quantitative reverse transcription polymerase chain reaction (RT-qPCR). Enzyme-linked immunosorbent assay (ELISA) was used to detect superoxide dismutase (SOD) and malondialdehyde (MDA) levels, and flow cytometry was performed to measure the mitochondrial membrane potential levels. In the HEI-OC1 oxidative stress model after transfection, the miR-122-5p level was decreased, whereas the FOXO3 level was increased, Moreover, the increased FOXO3 level diminished the cell viability, but promoted cell apoptosis. Apart from this, the Bcl-2 level was downregulated, while levels of Bax, c-caspase-3, c-caspase-9, ROS and MDA were upregulated. Meanwhile, the mitochondrial membrane potential level was also elevated. Overexpression of miR-122-5p was able to partially offset the effects of FOXO3 in the H₂O₂-treated HEI-OC1 cells. Collectively, miR-122-5p restrained the decrease in HEI-OC1 cell viability and apoptosis induced by treatment with H₂O₂.

The Role of Seminal Oxidative Stress Scavenging System in the Pathogenesis of Sperm DNA Damage in Men Exposed and Not Exposed to Genital Heat Stress

Responding to the need for the verification of some experimental animal studies showing the involvement of oxidative stress in germ cell damage in the heat-induced testis, we investigated the possibility of a direct relationship between seminal oxidative stress markers (total antioxidant capacity, catalase activity, superoxide dismutase activity, and malondialdehyde concentration) and ejaculated sperm chromatin/DNA integrity (DNA fragmentation and chromatin condensation abnormalities) in distinct groups of men exposed and not exposed to prolonged scrotal hyperthermia. A statistical increase in the proportion of sperm with DNA fragmentation was observed in all the studied subgroups compared to the fertile men. In turn, the groups subjected to heat stress as professional drivers or infertile men with varicocele presented greater disturbances in the oxidative stress scavenging system than men not exposed to genital heat stress. Based on the comparative analysis of the studied parameters, we can conclude that alterations in the seminal oxidative stress scavenging system are directly engaged in the pathogenesis of ejaculated sperm DNA damage regardless of the intensity of the impact of thermal insult. To the best of our knowledge, this study, for the first time, revealed the co-existence of oxidative stress and sperm DNA damage in the semen of professional drivers.

Sperm miR-34c-5p Transcript Content and Its Association with Sperm Parameters in Unexplained Infertile Men

MicroRNAs (miRNAs) play an essential role in regulatory functions during gametogenesis. There is evidence that dysregulation of miR-34c-5p is implicated in the pathogenesis of male infertility. Whether miR-34c-5p expression could represent the semen quality and be useful in prediction of the fertilizing ability in normozoospermic men was examined in this study. Normozoospermic infertile patients (n = 15) and fertile men (n = 15) were recruited from the Infertility Clinic of Ahvaz, Iran. Sperm contents of miR-34c-5p transcript in were assessed using real-time polymerase chain reaction. No significant differences were seen in semen characteristics between patients and fertile men. Infertile patients showed significant (p = 0.019) lower contents of sperm miR-34c-5p than fertile controls. Men with lower transcript contents of miR-34c-5p exhibit lower sperm motility and normal morphology. Sperm miR-34c-5p transcript with a relatively good diagnostic power discriminated unexplained infertile men (AUC = 0.751, 95% CI: 0.568-0.934; p = 0.019). Our findings show that sperm contents of miR-34c-5p transcript could reflect the quality of spermatozoa in etiology of unexplained male infertility and be helpful in predicting a successful pregnancy.

Role of miR-106-mediated mitogen-activated protein kinase signaling pathway in oxidative stress injury and inflammatory infiltration in the liver of the mouse with gestational hypertension

We aim to investigate the role of miR-106-mediated mitogen-activated protein kinase (MAPK) signaling pathway in oxidative stress (OS) injury and inflammatory infiltration in the liver of the mouse with gestational hypertension (GH). Ninety specific pathogen-free mice (Kunming species) during middle to late gestation were selected for the study. Fifteen mice were used as control, while the rest were used for establishing the GH model. The mice were assigned to six groups: normal group (normal gestation), model group (GH model), negative control group (GH model, intravenously injected with negative control vector), miR-106a-mimic group (GH model, intravenously injected with vector overexpressing miR-106a, which mimics the overexpression of endogenous mature miR-106a), SB203580 group (GH model, intravenously injected with MAPK pathway inhibitor SB203580), and miR-106a-mimic+SB203580 group (GH model, intravenously injected with SB203580 and vector overexpressing miR-106a). Fourteen days after electrical stimulation, all the groups except for the normal group had elevated blood pressure vs those on day 0 and 7. Compared with the normal group, the other groups had lower levels of miR-106a expression, nitric oxide, nitric oxide synthase, catalase, superoxide dismutase, S cell ratio, and interleukin-4 (IL-4) and IL-10 in the serum and liver as opposed to increased levels of blood pressure, p38MAPK mRNA expression, p-p38MAPK positive expression rate, protein expressions of p-p38MAPK, p-ERK, and p-JNK, H₂ O₂ and malondialdehyde in liver, G0/G1 cell ratio, apoptosis rate, and IL-6, interferon-γ (IFN-γ), and IFN-α in the serum and liver (all P < .05). The miR-106 overexpression or inhibiting MAPK signaling pathway can attenuate OS injury and inflammatory response in the liver of the mouse with GH, and the effect can be even better if both miR-106a overexpression and inhibiting MAPK pathway are applied. In conclusion, miR-106a overexpression can inhibit OS injury and inflammatory infiltration in the liver of the mouse with GH by mediating MAPK signaling pathway.

Assessment of seminal calcium and magnesium levels in infertile men with varicocele before and after varicocelectomy

BACKGROUND

Trace elements perform a vital role in all stages of human physiology, as well as reproduction.

OBJECTIVE

This study aimed to assess seminal calcium (Ca) and magnesium (Mg) in infertile men associated with varicocele (Vx).

MATERIALS AND METHODS

Overall, 50 men were divided into two groups: fertile men (n = 20) and infertile men who were scheduled for Vx surgical repair (n = 30). Exclusion criteria were as follows: azoospermia, smoking, leukocytospermia, and consumption of Ca and/or Mg supplements. All cases were subjected to history taking and clinical examination. Semen analysis and assessment of seminal Ca and Mg by the colorimetric method were carried out for all cases at the base point and 3 months postvaricocelectomy.

RESULTS

Generally, the mean seminal Ca and Mg levels demonstrated significant decreases in infertile men with Vx compared with the healthy fertile men linked to higher Vx grade as well as Vx bilaterality. These seminal decreases demonstrated significant increases after Vx surgical repair. Collectively, seminal Ca and Mg levels showed a significant positive correlation (r = 0.665, p= 0.001). Besides, seminal Ca, Mg levels, and Ca/Mg ratio showed significant positive correlation with sperm concentration (r = 0.479, p = 0.001; r = 0.541, p = 0.001; r = 0.282, p = 0.001, respectively), sperm motility percentage (r = 0.493, p = 0.001; r = 0.477, p = 0.001; r = 0.353, P = 0.001, respectively), and sperm normal forms percentage (r = 0.578, p = 0.001; r = 0.520, p = 0.001; r = 0.430, p = 0.001, respectively).

DISCUSSION AND CONCLUSION

Seminal Ca and Mg levels and Ca/Mg ratio are significantly decreased in infertile men associated with Vx compared with fertile men with significant increases after varicocelectomy.

Using miRNAs as diagnostic biomarkers for male infertility: opportunities and challenges

The non-coding genome has been extensively studied for its role in human development and diseases. MicroRNAs (miRNAs) are small non-coding RNAs, which can regulate the expression of hundreds of genes at the post-transcriptional level. Therefore, any defects in miRNA biogenesis or processing can affect the genes and have been linked to several diseases. Male infertility is a clinical disorder with a significant number of cases being idiopathic. Problems in spermatogenesis and epididymal maturation, testicular development, sperm maturation or migration contribute to male infertility, and many of these idiopathic cases are related to issues with the miRNAs which tightly regulate these processes. This review summarizes the recent research on various such miRNAs and puts together the candidate miRNAs that may be used as biomarkers for diagnosis. The development of strategies for male infertility treatment using anti-miRs or miRNA mimics is also discussed. Although promising, the development of miRNA diagnostics and therapeutics is challenging, and ways to overcome some of these challenges are also reviewed.

The Roles of MicroRNAs in Male Infertility

MicroRNAs applications were vastly studied throughout the years, spanning from potential cancer biomarkers to targeted therapies for various diseases. Out of these utilizations, this paper focuses on their role in male infertility. Approximately 10–15% of worldwide couples are affected by infertility. Out of these, 50% are due to male determinants. The majority of cases still have an undetermined cause. Previous studies have found that the aberrant expression of microRNAs could be linked to certain reproductive dysfunctions in males. Further on, this study looked into the most recent literature published on this subject in order to assess the connection between the up-/down-regulation of various microRNAs and the roles they play in male infertility. MicroRNAs were found to be abundant and stable in the seminal liquid, which led to a facile identification using regular RNA detection methods. It was observed that the concentration of microRNAs in semen was modified in the case of patients suffering from asthenozoospermia and azoospermia. Moreover, idiopathic male infertility was associated with a single nucleotide polymorphism of the microRNA binding site. Future studies should focus their attention on discovering future treatments against male infertility targeting specific microRNAs and also on developing new and improved contraceptive methods.

Investigating the Role of the microRNA-34/449 Family in Male Infertility: A Critical Analysis and Review of the Literature

There is a great body of evidence suggesting that in both humans and animal models the microRNA-34/449 (miR-34/449) family plays a crucial role for normal testicular functionality as well as for successful spermatogenesis, regulating spermatozoa maturation and functionality. This review and critical analysis aims to summarize the potential mechanisms via which miR-34/449 dysregulation could lead to male infertility. Existing data indicate that miR-34/449 family members regulate ciliogenesis in the efferent ductules epithelium. Upon miR-34/449 dysregulation, ciliogenesis in the efferent ductules is significantly impaired, leading to sperm aggregation and agglutination as well as to defective reabsorption of the seminiferous tubular fluids. These events in turn cause obstruction of the efferent ductules and thus accumulation of the tubular fluids resulting to high hydrostatic pressure into the testis. High hydrostatic pressure progressively leads to testicular dysfunction as well as to spermatogenic failure and finally to male infertility, which could range from severe oligoasthenozoospermia to azoospermia. In addition, miR-34/449 family members act as significant regulators of spermatogenesis with an essential role in controlling expression patterns of several spermatogenesis-related proteins. It is demonstrated that these microRNAs are meiotic specific microRNAs as their expression is relatively higher at the initiation of meiotic divisions during spermatogenesis. Moreover, data indicate that these molecules are essential for proper formation as well as for proper function of spermatozoa per se. MicroRNA-34/449 family seems to exert significant anti-oxidant and anti-apoptotic properties and thus contribute to testicular homeostatic regulation. Considering the clinical significance of these microRNAs, data indicate that the altered expression of the miR-34/449 family members is strongly associated with several aspects of male infertility. Most importantly, miR-34/449 levels in spermatozoa, in testicular tissues as well as in seminal plasma seem to be directly associated with severity of male infertility, indicating that these microRNAs could serve as potential sensitive biomarkers for an accurate individualized differential diagnosis, as well as for the assessment of the severity of male factor infertility. In conclusion, dysregulation of miR-34/449 family detrimentally affects male reproductive potential, impairing both testicular functionality as well as spermatogenesis. Future studies are needed to verify these conclusions.

Altered microRNAs expression levels of sperm and seminal plasma in patients with infertile ejaculates compared with normozoospermic males

Approximately 15% of couples are unable to conceive after one year of unprotected intercourse. Because sperm can be accessed with ease, it is reasonable to search for non-invasive biomarkers in semen. MicroRNAs are a family of short single-stranded non-coding RNA molecules that are capable of regulating gene expression and causing mRNA degradation. We studied the most common 11 spermatogenesis-related microRNAs expression levels in sperm and seminal plasma from patients with oligozoospermic or asthenozoospermic ejaculates, and in men with normozoospermic ejaculates. Five of these miRNAs were significantly upregulated and three were downregulated in infertile males compared to men with normozoospermic ejaculates. A statistically significant negative correlation was found between the sperm concentration and several microRNA expression level (let-7a, miR-7-1-3p, miR-141, miR-200a, and miR-429, p < 0.0001) both in sperm and in seminal plasma. We also found positive correlation between sperm concentration and some miRNA expression levels (miR-15b, miR-34b, and miR-122, p < 0.001) in sperm and in seminal plasma. This is the first study to demonstrate differences between sperm and seminal plasma miRNA expression level and to identify a correlation between the sperm concentration and miRNAs expression level. Therefore, these MiRNAs could have the potential be used as non-invasive biomarkers to diagnose males with impaired sperm production.

The Vehicle Determines the Destination: The Significance of Seminal Plasma Factors for Male Fertility

Of all human infertility cases, up to 50% show contributing factors leading to defects in the male reproductive physiology. Seminal plasma (SP) is the biological fluid derived from the male accessory sex gland which carries spermatozoa passing throughout the male and female reproductive tract during ejaculation. It contains a complicated set of heterogeneous molecular structures, including proteins, cell-free nucleic acid (DNA, microRNA and LncRNA), and small-molecule metabolites as well as inorganic chemicals (ions). For a long time, the substantial significance of seminal plasma factors’ functions has been underestimated, which is restricted to spermatozoa transport and protection. Notably, significant advancements have been made in dissecting seminal plasma components, revealing new insights into multiple aspects of sperm function, as well as fertilization and pregnancy outcomes in recent years. In this review, we summarize the state-of-art discoveries regarding SP compositions and their implications in male fertility, particularly describing the novel understanding of seminal plasma components and related modifications using “omics” approaches and mainly focusing on proteome and RNA-seq data in the latest decade. Meanwhile, we highlighted the proposed mechanism of the regulation of SP molecules on immunomodulation in the female reproductive tract. Moreover, we also discussed the proteins investigated as non-invasive diagnosis biomarkers for male infertility in the clinic.

Investigation of molecular cryopreservation, fertility potential and microRNA-mediated apoptosis in Oligoasthenoteratozoospermia men

Investigation of the cryo-injury mechanism can provide novel insight into cryopreservation. The objective of this study is to assess the effect of cryopreservation on fertility potential, motility, oxidative stress (OS), DNA fragmentation, microRNAs (miRNAs), and apoptotic target genes in the infertile men compared to the fertile men. All 40 samples were divided into two leading groups of fresh and cryopreserved sperms. Each main group was subdivided into three groups including, Normozoospermia, and Mild, and Severe Oligoasthenoteratozoospermia (OAT). In all collected samples the following were assessed: microRNA-34c (miR-34c) and miR-184, P53 and Caspase9 using Quantitative real-time polymerase chain reaction (RT-PCR), malondialdehyde (MDA), Superoxide dismutase (SOD) using imaging multi-mode reader, and DNA fragmentation using Sperm DNA Fragmentation Assay Test (SDFA). Within the studied groups, immotile spermatozoa were increased due to cryopreservation. We observed an increasing levels of SOD, MDA, and DNA fragmentation. Also, cryopreservation was associated with decreasing the expression of P53, mir-43c, and miR-184 while capase9 was showed enhancing expression after freeze-thawing of sperm cells. During cryopreservation, sperm fertility and motility were influenced via apoptosis cascade-mediated mitochondrial dysfunctions such as caspase9. Also, we found that miR-34c, miR184, and P53 could impact fertility potential. In Addition, there was a meaningful correlations between microRNAs and motility post freeze-thawing process in Severe Oligoasthenoteratozoospermia men.

Transcript Isoforms of SLC7A11-AS1 Are Associated With Varicocele-Related Male Infertility

Oxidative stress is one of the crucial mediators of varicocele-related male infertility. Recently, roles of long noncoding RNAs (lncRNAs) in oxidative stress have begun to emerge, however, little is known about their role in male infertility. The aim of this study was to determine the role of lncRNA SLC7A11-AS1 in varicocele-related male infertility. Through a high-throughput bioinformatics investigation, we predicted that lncRNA SLC7A11-AS1 might be involved in this type of infertility. The reactive oxygen species (ROS) levels and expression levels of SLC7A11-AS1 isoforms were evaluated in ejaculated spermatozoa of 25 infertile men with varicocele and 17 fertile individuals as control. Isoform 6 of SLC7A11-AS1 that showed a significant elevation in infertile men with varicocele relative to the fertile group was overexpressed in testicular-derived carcinoma cell lines (NT2 and NCCIT) followed by assessment of ROS, glutathione (GSH), lipid peroxidation, and cell viability. Overexpression of SLC7A11-AS1 isoform 6 in NT2 and NCCIT cell lines resulted in a significant downregulation of SLC7A11 gene expression, which consequently decreased GSH levels and concomitantly increased ROS levels and enhanced lipid peroxidation, which jeopardized cell survival and promoted cell death. Our finding revealed a potential role of oxidative-related lncRNAs in the pathophysiology of male infertility associated with varicocele.

Identification and verification of hub microRNAs in varicocele rats through high-throughput sequencing and bioinformatics analysis

Varicocele (VC) is the most common treatable cause of infertility, but it is difficult to distinguish fertile from infertile VC populations because the pathogenesis is unclear. In order to study the related mechanism of VC causing male sterility, we made VC rats model by surgery, analyzed the rat epididymal sperm, and use the transcriptome sequencing compared all the miRNA expression differences in testicular tissue between VC rats, surgical treatment rats and control rats. The differentially expressed miRNAs (DEMs) of testicular tissue were also screened by the edgeR package in R software. We found that rno-miR-210-3p, rno-miR-6316, rno-miR-190a-5p and rno-miR-135b-5p were key miRNAs for VC and they were all up-regulated in VC samples and they are enriched in regulation of immune system process (GO:0002683), innate immune system (R-RNO-168,249) and apoptotic signaling pathway (GO:0097190). We hypothesize that negative regulation of immune system and apoptosis play an important role in the occurrence and development of VC, and it is induced the abnormal expression of target genes (such as Kitlg, Cxcl12) may involve in the development of VC associated infertility. Four key miRNAs, rno-miR-210-3p, rno-miR-6316, rno-miR-190a-5p and rno-miR-135b-5p, as well as their target genes are critical in VC, which could have attractive applications to provide new biomarkers for VC.

Increased Sperm DNA Fragmentation in Infertile Men with Varicocele: Relationship with Apoptosis, Seminal Oxidative Stress, and Spermatic Parameters

This study intends to determine the extent of nuclear sperm injury in patients with varicocele and to investigate its relationship with apoptosis and oxidative stress (OS). Ejaculated sperm samples from 51 patients diagnosed with varicocele and 29 fertile men were examined. According to the guidelines, the patient's sperm samples were classified into varicocele with normal semen parameters (n = 11) and varicocele with abnormal semen parameters (n = 40). Sperm DNA fragmentation was assessed using terminal deoxynucleotidyl transferase dUTP nick end labeling assay. The proportion of both viable and dead spermatozoa with externalized phosphatidylserine (PS) was detected by the bivariate annexin V/6-CFDA staining method. Seminal malondialdehyde (MDA) amounts and antioxidant enzymes activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) were measured spectrophotometrically. Sperm DNA fragmentation, viable spermatozoa with externalized PS, and MDA levels were significantly higher in studied subgroups of patients with varicocele, either with normal or with abnormal semen parameters than controls. The seminal antioxidant enzymes activities were significantly reduced in both subgroups of patients with varicocele compared to the controls. The percentage of spermatozoa with fragmented DNA was positively correlated to the MDA level as well as the proportion of viable spermatozoa with externalized PS. However, the decreased seminal antioxidant status was negatively correlated with the increased proportion of sperm DNA fragmentation and apoptotic spermatozoa. Impaired seminal antioxidant profile and increased seminal level of lipid peroxidation may be involved in the pathophysiological mechanisms of cell death-mediated DNA breaks in patients with varicocele.

Assessment of seminal YKL-40 in infertile men with varicocele

Several studies attempted to explain the negative impact of varicocele on spermatogenesis and fertilisation processes. YKL-40 is a novel glycoprotein biomarker that had been associated with several diseases. This quasi-interventional study aimed to assess the seminal levels of YKL-40 in infertile men with varicocele before and after varicocelectomy. Overall, 50 men were included in this study divided into 20 healthy fertile men and 30 infertile oligoasthenoteratozoospermic (OAT) men with varicocele that underwent varicocelectomy. All participants were subjected to history taking, clinical examination and scrotal Doppler. Also, semen analysis and seminal YKL-40 assessment were carried out in the start and 6 months after varicocele surgical repair. The results showed a significant increase in the mean seminal YKL-40 level in infertile OAT men with varicocele compared with the healthy fertile men. Six months post-varicocelectomy, the mean seminal KYL-40 level exhibited significant decreases correlated with improved sperm parameters. Overall, seminal levels of YKL-40 showed significant negative correlations with sperm concentration, total sperm motility and sperm normal morphology. It could be concluded that seminal YKL-40 is elevated in infertile OAT men with varicocele where varicocelectomy induces decreased seminal YKL-40 levels correlated with improved semen parameters.

Oxidative stress-related miRNAs in spermatozoa may reveal the severity of damage in grade III varicocele

Varicocele is associated with excessive production of reactive oxygen species (ROS). Although the harmful effects of ROS on sperm DNA, proteins and lipids are well documented, its impact on the expression of miRNAs in spermatozoa has not been fully understood. In this study, the expression patterns of microRNAs (miRNAs), miR-21, miR-34a and miR-122a as well as the level of ROS in the fertile control (FC; proven fertility without varicocele, n = 15) and grade III varicocele patients with normal (VN; n = 15) and abnormal (VA; n = 15) spermogram were investigated. The real-time PCR was performed to analyse the expression of the miRNAs, while oxidative stress was evaluated by measuring the concentrations of MDA. Our results showed that the expression levels of miR-21 (p = .001), miR-34a, (p = .007) and miR-122a (p < .001) were significantly decreased in spermatozoa of VN and VA patients in comparison with the fertile group. Also, increased levels of oxidative stress were detected in semen samples of varicocele patients compared with the fertile control (p < .0001). Overall, these findings demonstrate oxidative stress changes the expression pattern of some miRNAs, and these alterations could be a valuable diagnostic marker for the diagnosis and prognosis of varicocele-induced oxidative stress to retain the male fertility during the spermatogenesis process.

Varicocele Repair Prior to Assisted Reproductive Technology: Patient Selection and Special Considerations

Clinical varicoceles are one of the most commonly identified physical exam abnormalities in men presenting with infertility. Clinical varicoceles can cause impaired spermatogenesis and surgical correction can improve semen parameters in select men. Increasingly, andrologists are performing varicocele repairs prior to intrauterine insemination (IUI), in vitro fertilization (IVF), and intracytoplasmic sperm injection (ICSI) to boost male fertility potential. In this review, we evaluated the available literature 1) to determine if varicocelectomy prior to IUI or assisted reproductive technologies proved to improve sperm production or pregnancy outcomes; and 2) to identify who may be the ideal candidate for pre-IUI/ART varicocelectomy. Overall, few studies have explored this topic and little can be concluded about the impact of varicocelectomy prior to IUI. The evidence, however, does support that correcting a clinical varicocele can increase pregnancy outcomes in couples who plan to pursue IVF or ICSI. When selecting patients for varicocelectomy prior to IUI or ART, clinicians should evaluate female age as improvement in semen parameters can take 6 months after varicocelectomy and this duration of time may be deleterious in cases of advanced maternal age when each cycle becomes increasingly important. Overall, the currently limited literature regarding clinical varicoceles correction demonstrates that pregnancy rates can be increased when comparing patients who have undergone varicocelectomy prior to ART with those who had clinical varicocele but did not undergo surgery.

Downregulation of microRNA-873 attenuates insulin resistance and myocardial injury in rats with gestational diabetes mellitus by upregulating IGFBP2

Gestational diabetes mellitus (GDM) is a metabolic disorder characterized by insulin resistance, and patients with GDM have a higher risk of cardiovascular disease. Multiple microRNAs (miRNAs) are reported to be involved in the regulation of myocardial injury. Moreover, miR-873 was predicted to target insulin-like growth factor binding protein 2 (IGFBP2) through bioinformatic analysis, which was further confirmed using a luciferase assay. Thus, our objective was to assess whether microRNA-873 (miR-873) affects insulin resistance and myocardial injury in an established GDM rat model. The GDM rats were treated with miR-875 mimic or inhibitor or IGFBP2 siRNA. The effects of miR-875 and IGFBP2 on the cardiac function, insulin resistance, and myocardial injury were evaluated by hemodynamic measurements, determination of biochemical indices of myocardium and serum, and insulin homeostatic model assessment. The results indicated that downregulation of miR-873 upregulated the expression of IGFBP2 and promoted the activation of phosphatidylinositol-3 kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) axis. With downregulation of miR-873 in GDM rats, the cardiac function was improved and the myocardial apoptosis was inhibited, coupled with elevated activity of superoxide dismutase, carbon monoxide synthase, and the nitric oxide content. In addition, the inhibition of miR-873 in GDM rats modulated the insulin resistance and reduced myocardial apoptosis. Overall, the data showed that inhibition of miR-873 by targeting IGFBP2 may regulate the insulin resistance and curtail myocardial injury in GDM rats through activating the PI3K/AKT/mTOR axis, thus providing a potential means of impeding the progression of GDM.

Association between seminal granulysin and malondialdehyde in infertile men with varicocele and the potential effect of varicocelectomy

This study assessed the seminal plasma granulysin and malondialdehyde (MDA) levels in patients suffering from varicocele-associated infertility prior to and after varicocelectomy. This study was conducted on 34 infertile men with varicocele (group A) and same patients after varicocelectomy (group B) and 32 fertile normozoospermic males (group C). A detailed history taking, clinical examination, scrotal doppler ultrasound for varicocele diagnosis and grading, semen analysis and estimation of seminal granulysin and MDA before and after varicocelectomy were done to all participants. The mean (SD) granulysin and MDA levels in patients with varicocele were higher than in controls with highly significant differences. Post-operatively, there was a significant reduction in mean (SD) granulysin and in MDA level. Basal seminal granulysin positively correlated with basal seminal MDA, abnormal forms and negatively correlated with basal sperm count, concentration, and progressive motility. The receiver operating characteristic curve of seminal granulysin and MDA levels were conducted for discrimination between infertility cases with varicocele and control groups. Excellent AUCs were found for both markers (AUC = 0.971, 0.991 respectively). We concluded that high levels of granulysin and MDA in the semen of infertile males with varicocele negatively impact their spermatogenesis. Varicocelectomy leads to the improvement of semen parameters and significantly decreases seminal plasma granulysin and MDA levels. Hence, seminal granulysin and MDA could be used as a prognostic test in infertile patients with varicocele.

MicroRNAs association with azoospermia, oligospermia, asthenozoospermia, and teratozoospermia: a systematic review

Infertility is a major health problem across the world. One of the main reasons for male infertility are defects in sperm. Semen analysis is the most common test utilized to evaluate male fertility and since it suffers from multiple drawbacks, reproduction scientists have tried to find new molecular markers for detecting sperm defects. MicroRNAs (miRNAs) are small molecules in cells which take part in regulating gene expression. Various studies have confirmed miRNAs to have a role in defining multiple sperm characteristics, including sperm count, motility, and morphology. In this paper, we have systematically reviewed the role of miRNAs in infertile men with sperm defects including azoospermia, oligospermia, asthenozoospermia, and teratozoospermia. Also, we have assembled various bioinformatics tools to come up with a pipeline for predicting novel miRNAs which could possibly participate in sperm count, motility, and morphology. Also, related KEGG and GO terms for predicted miRNAs have been included in order to highlight their role in sperm function. Our study emphasizes the potential role of miRNAs in male infertility and provides a general overview for future studies aiming to find robust molecular markers for this condition.

Seminal SIRT1-oxidative stress relationship in infertile oligoasthenoteratozoospermic men with varicocele after its surgical repair

This work assessed seminal SIRT1-oxidative stress (OS) relationship in infertile oligoasthenoteratozoospermic (OAT) men after varicocele repair. Overall, thirty OAT men with varicocele were investigated. Inclusion criteria were infertile males (males who were unable to initiate a pregnancy within 1 year of regular unprotected intercourse), confirmed OAT and normal female factor. These cases were subjected to history taking, clinical checkup and semen analysis. In their semen, seminal SIRT1, malondialdehyde (MDA) and glutathione peroxidase (GPx) levels were assessed. These men were subjected to varicocele surgical repair and were followed up for 3 months. Post-operatively, the mean seminal SIRT1, GPx levels showed significant increases and the mean MDA level showed significant decrease compared to the pre-operative levels linked to improved sperm parameters. The mean seminal SIRT1, GPx, MDA levels showed more significant improvement in grade III varicocele cases compared to grade II cases after surgical repair. Seminal SIRT1 levels showed significant positive correlations with sperm concentration, sperm motility, sperm normal morphology, seminal GPx levels and a significant negative correlation with seminal MDA levels. It could be concluded that seminal SIRT1 is significantly decreased in infertile OAT men with varicocele after its surgical repair linked to improved sperm parameters as well as seminal OS.

Sperm miR-15a and miR-29b are associated with bull fertility

MicroRNAs modulate male fertility by regulating gene expression. In this study, dynamics of sperm miR-15a, miR-29b and miR-34a from high fertility (HF) and low fertility (LF) bulls using RT-qPCR were evaluated. Bioinformatic tools were employed to ascertain genes of interest of the sperm miRNAs. The expression levels of p53, BCL2, BAX and DNMT1 in bull spermatozoa were determined by immunoblotting. MicroRNA levels of miR-15a and miR-29 were higher in LF sires when compared with those present in HF bulls. Expression levels of miR-34a did not differ between the two groups. We found an inverse correlation between miR-15a and bull fertility. MiR29-b was also negatively associated with fertility scores. BCL2 and DNMT1 were higher in HF bulls while BAX was higher in the LF group. Our data showed a positive correlation between BCL2 and bull fertility. In addition, DNMT1 was positively associated with bull fertility. Furthermore, levels of BAX were negatively linked with bull fertility scores. Identification of miRNAs found in the spermatozoa of sires with different in vivo fertility helps understand the alterations in the fertilising capacity from cattle and other mammals. These potential biomarkers can be used in reproductive biotechnology as fertility markers to assess semen quality and predict male fertility.

Folic acid supplementation reduces multigenerational sperm miRNA perturbation induced by in utero environmental contaminant exposure

Persistent organic pollutants (POPs) can induce epigenetic changes in the paternal germline. Here, we report that folic acid (FA) supplementation mitigates sperm miRNA profiles transgenerationally following in utero paternal exposure to POPs in a rat model. Pregnant founder dams were exposed to an environmentally relevant POPs mixture (or corn oil) ± FA supplementation and subsequent F1-F4 male descendants were not exposed to POPs and were fed the FA control diet. Sperm miRNA profiles of intergenerational (F1, F2) and transgenerational (F3, F4) lineages were investigated using miRNA deep sequencing. Across the F1-F4 generations, sperm miRNA profiles were less perturbed with POPs+FA compared to sperm from descendants of dams treated with POPs alone. POPs exposure consistently led to alteration of three sperm miRNAs across two generations, and similarly one sperm miRNA due to POPs+FA; which was in common with one POPs intergenerationally altered sperm miRNA. The sperm miRNAs that were affected by POPs alone are known to target genes involved in mammary gland and embryonic organ development in F1, sex differentiation and reproductive system development in F2 and cognition and brain development in F3. When the POPs treatment was combined with FA supplementation, however, these same miRNA-targeted gene pathways were perturbed to a lesser extend and only in F1 sperm. These findings suggest that FA partially mitigates the effect of POPs on paternally derived miRNA in a intergenerational manner.

14-3-3 epsilon plays an important role in testicular germ cell apoptosis: A functional proteomic study of experimental varicocele

The latest perspective indicates that apoptotic dysregulation is an important mechanism in male infertility induced by varicocele. To elucidate the molecular mechanism of apoptosis caused by varicocele, we used proteomics (2D-MALDI-TOF MS) to identify the altered proteins in the testes of experimental varicocele rats compared with the control. Here, 21 significantly different protein spots were detected by proteomics technology. 14-3-3 epsilon (14-3-3ε) was our subsequent research target because of its function in apoptosis. The expression of 14-3-3ε in rat testes was confirmed by Western blot and immunohistochemistry, and the terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) method was used to analyse the apoptosis of germ cells. GC-1 spg cells transfected with small interfering RNA were used to confirm the function of 14-3-3ε in vitro. 14-3-3ε protein expression decreased, accompanied by a higher apoptosis index in rat testes of the varicocele group. Furthermore, 14-3-3ε siRNA-treated GC-1 spg cells caused the upregulation of the apoptotic rate detected by flow cytometry. The expression of Bax and Bcl-2 was found to be regulated by 14-3-3ε in vitro. Our investigation demonstrated the pro-apoptotic function of the downregulation of 14-3-3ε, which may play an important role in germ cell apoptosis induced by varicocele.

Assessment of seminal granulysin in infertile men with varicocele

Varicocele has a common association with male infertility, but its exact role is still debated. Apoptosis has been suggested as one of the mechanisms of varicocele-associated infertility. Granulysin is a molecule that plays a role in apoptosis with no previous study about its role in male infertility. This case-controlled study aimed to assess seminal plasma granulysin level in infertile patients with varicocele. This study involved 90 men that were allocated into fertile normozoospermic men (n = 20), infertile men without varicocele (n = 30) and infertile men with varicocele (n = 40). These men were subjected to history taking, clinical examination, semen analysis and estimation of seminal granulysin. In general, seminal granulysin level was significantly elevated in infertile men compared with fertile men. Infertile men with varicocele showed significantly higher seminal granulysin compared with infertile men without varicocele, in bilateral varicocele cases and in grade III varicocele. Seminal granulysin level was negatively correlated with sperm concentration, sperm motility, sperm normal forms percentage and testicular volumes. It is concluded that increased seminal granulysin has a negative impact on spermatogenesis in infertile men in general and in infertile men associated with varicocele in particular.

Seminal SIRT1 expression in infertile oligoasthenoteratozoospermic men with varicocoele

In a case-controlled study, we assessed the expressed seminal NAD-dependent protein deacetylase (SIRT1) expression in infertile oligoasthenoteratozoospermic (OAT) men associated with varicocoele. Our study involved 81 men, recruited from the University hospitals, after ethical approval and informed consent. They were allocated into fertile normozoospermic men (n = 23), infertile OAT men without varicocoele (n = 23) and infertile OAT men with varicocoele (n = 35). Inclusion criteria consisted of confirmation of abnormal semen parameters and normal female partners whereas exclusion criteria were leukocytospermia, tobacco smoking, hormonal therapy, immunological disorders, dyslipidemia, hypogonadism, cardiovascular disorders, morbid obesity, and hepatic or renal failures. All participants had an interview to assess clinical history, clinical examination, semen analysis, and estimation of seminal SIRT1 expression. Seminal SIRT1 expression was significantly lower in infertile OAT men than fertile men. Among infertile OAT men, seminal SIRT1 expression was significantly lower in those with varicocoele than in those without. Additionally, seminal SIRT1 expression was significantly lower in varicocoele grade III cases compared with other grades. Seminal SIRT1 expression was positively correlated with sperm concentration (r = 0.327, p = 0.001), total sperm motility (r = 0.532, p = 0.001), and sperm normal forms (r = 0.469, p = 0.001). Our results suggest that seminal SIRT1 expression has a role of male infertility being significantly decreased in infertile OAT men in general and in infertile OAT men associated with varicocoele in particular.

Regulatory Functions of MicroRNAs in Male Reproductive Health: A New Approach to Understanding Male Infertility

MicroRNAs (miRNAs) are a novel class of small noncoding RNAs (ncRNAs) that play critical roles in regulation of gene expression, especially at posttranscriptional level. Over the past decade, the degree to which miRNAs are involved in male infertility has become clear. They are expressed in a cell- or phase-specific manner during spermatogenesis and play crucial role in male reproductive health. Therefore, dysregulation of miRNAs in testicular cells can be considered as a molecular basis for reproductive failure and male infertility. The abnormal expression pattern of miRNAs can be transmitted to the offspring via assisted reproductive techniques (ART) and results in the birth of children with a higher risk of infertility, congenital abnormalities, and morbidity. This review expounds on the miRNAs reported to play essential roles in somatic cells development, germ cells differentiation, steroidogenesis, normal spermatogenesis, sperm maturation, and male infertility, as well as emphasizes their importance as minimally invasive biomarkers of male infertility.

Effect of varicocelectomy and/or mast cells stabilizer on sperm DNA fragmentation in infertile patients with varicocele

This study aimed to assess the effect of varicocelectomy and/or mast cells (MCs) stabilizer on sperm DNA fragmentation in infertile men with varicocele (Vx). Overall, 120 infertile patients were randomized to three equal treatment arms; patients that underwent varicocelectomy, patients on 1 mg ketotifen twice daily for three months, and patients that underwent varicocelectomy followed with 1 mg ketotifen twice daily for three months. These patients were subjected to history taking, clinical examination, semen analysis, and estimation of sperm DNA fragmentation index (DFI). After 3 months, all investigated groups showed significant improvement regarding the mean total sperm count, sperm concentration, total sperm motility, and sperm normal forms percentage compared with the pre-treatment data. As well, the mean sperm DFI was significantly improved compared with the pre-treatment data; in men that underwent varicocelectomy (34.6% vs. 28.3%), in men on MC stabilizer only (33.4% vs. 27.8%), and in men that underwent varicocelectomy followed by MC stabilizer (34.3% vs. 25.1%). Sperm DFI improvement percentages showed the highest improvement in men that underwent varicocelectomy followed with MC stabilizer compared with the other two groups (26.8% vs. 18.2%, 16.8%). Sperm DFI improvement percentages showed significant increases in the infertile patients with Vx grade III compared to Vx grade II in all investigated groups. It is concluded that in infertile men associated with Vx and high sperm DFI, surgical repair followed with MCs stabilizer significantly improve sperm DFI compared with either surgical repair or MCs stabilizer alone.

LncRNA gadd7, increased in varicocele patients, suppresses cell proliferation and promotes cell apoptosis

Varicocele-related sperm damages are usually caused by oxidative stresses. Growing evidence indicates that lncRNA growth arrested DNA-damage inducible gene 7 (gadd7) is involved in the regulation of the oxidative stress responses. In this study, we measured the expression level of gadd7 in the sperm and found that the expression of gadd7 was significantly up-regulated in patients with varicocele compared with the healthy control. The relative expression level of gadd7 was negatively correlated with the sperm count. Overexpression of gadd7 suppressed cell proliferation and promoted cell apoptosis in mouse spermatocyte-derived cell lines GC-1 and GC-2. Furthermore, the protein level of Bax was raised while Bcl2 expression was reduced after overexpression of gadd7. This work provides a potential novel insight for the varicocele-related sperm impairment and male infertility.