Autophagy may play an important role in varicocele

Research progress on the role of autophagy in the development of varicocele

Varicocele (VC) is a common cause of infertility in men. Pathophysiological changes caused by VC, such as testicular hypoxia, high temperatures, oxidative stress, abnormal reproductive hormones, and Cd accumulation, can induce autophagy, thus affecting the reproductive function in patients with this condition. Autophagy regulators can be classified as activators or inhibitors. Autophagy activators upregulate autophagy, reduce the damage to the testis and epididymis, inhibit spermatogenic cell apoptosis, and protect fertility. In contrast, autophagy inhibitors block autophagy and aggravate the damage to the reproductive functions. Therefore, elucidating the role of autophagy in the occurrence, development, and regulation of VC may provide additional therapeutic options for men with infertility and VC. In this review, we briefly describe the progress made in autophagy research in the context of VC.

Hypoxia enhances autophagy level of human sperms

The relationship between oxygen sensing and autophagy in human sperms was explored in this study. Health semen and asthenozoospermia (astheno) semen were incubated with hypoxia-inducible factor-1α (HIF-1α) interferents, i.e., lificiguat (YC-1) or cobalt chloride (CoCl2), respectively. Label-free quantitative proteomic technology was used to identify the differentially expressed proteins in human semen under the hypoxia condition. Selected proteins were detected with ELISA. It was found that the autophagy levels of sperm in the YC-1 + health group or CoCl2 + astheno group increased while the vitality decreased. A total of 17, 34 and 35 differentially expressed proteins were observed in the Astheno group, the YC-1 + health group and the CoCl2 + astheno group, respectively. These proteins were primarily associated with protein processing in endoplasmic reticulum, Th17 cell differentiation, progesterone-mediated oocyte maturation, glycolysis/gluconeogenesis, HIF-1 signaling pathway, biosynthesis of amino acids, and carbon metabolism. The expression levels of protein HIF-1α, LC3B, histone H4, cathepsin L and ENO1 changed significantly in the groups. The study suggests that hypoxia can increase sperm autophagy level and reduce their vitality through HIF-1 signaling pathway and glycolysis/gluconeogenesis signaling pathway. Furthermore, proteins histone H4, cathepsin L, glutathione synthetase and ENO1 are proposed as potential biomarkers of autophagy and vitality in asthenozoospermia sperm.

The Evolving Landscape of Male Varicocele Pathophysiology in the Era of Multi-Omics: A Narrative Review of the Current Literature

Male-factor infertility is implicated in over half of the millions of cases of infertility worldwide, and varicoceles are the most common correctable cause of male-factor infertility. The pathophysiologic mechanism for varicoceles is complex and next-generation technologies offer promising insights into the molecular underpinnings of this condition. In this narrative review, we highlight historical and contemporary paradigms associated with varicoceles, with an emphasis on the biological underpinnings of this disease. Specifically, we review the literature describing the underlying causes of varicoceles, discuss the molecular and cellular mechanisms causing pathological changes in some (but not all) men, and highlight key articles regarding the next-generation analyses (e.g., transcriptome, epigenome, proteome, and microbiome) being applied to better understand the condition and its treatment. These data demonstrate an ongoing evolution of the knowledge of varicoceles and the potential for improved personalized care in the future for men with this condition.

The constructive and destructive impact of autophagy on both genders' reproducibility, a comprehensive review

Reproduction is characterized by a series of massive renovations at molecular, cellular, and tissue levels. Recent studies have strongly tended to reveal the involvement of basic molecular pathways such as autophagy, a highly conserved eukaryotic cellular recycling, during reproductive processes. This review comprehensively describes the current knowledge, updated to September 2022, of autophagy contribution during reproductive processes in males including spermatogenesis, sperm motility and viability, and male sex hormones and females including germ cells and oocytes viability, ovulation, implantation, fertilization, and female sex hormones. Furthermore, the consequences of disruption in autophagic flux on the reproductive disorders including oligospermia, azoospermia, asthenozoospermia, teratozoospermia, globozoospermia, premature ovarian insufficiency, polycystic ovarian syndrome, endometriosis, and other disorders related to infertility are discussed as well.Abbreviations: AKT/protein kinase B: AKT serine/threonine kinase; AMPK: AMP-activated protein kinase; ATG: autophagy related; E2: estrogen; EDs: endocrine disruptors; ER: endoplasmic reticulum; FSH: follicle stimulating hormone; FOX: forkhead box; GCs: granulosa cells; HIF: hypoxia inducible factor; IVF: in vitro fertilization; IVM: in vitro maturation; LCs: Leydig cells; LDs: lipid droplets; LH: luteinizing hormone; LRWD1: leucine rich repeats and WD repeat domain containing 1; MAP1LC3: microtubule associated protein 1 light chain 3; MAPK: mitogen-activated protein kinase; MTOR: mechanistic target of rapamycin kinase; NFKB/NF-kB: nuclear factor kappa B; P4: progesterone; PCOS: polycystic ovarian syndrome; PDLIM1: PDZ and LIM domain 1; PI3K: phosphoinositide 3-kinase; PtdIns3P: phosphatidylinositol-3-phosphate; PtdIns3K: class III phosphatidylinositol 3-kinase; POI: premature ovarian insufficiency; ROS: reactive oxygen species; SCs: Sertoli cells; SQSTM1/p62: sequestosome 1; TSGA10: testis specific 10; TST: testosterone; VCP: vasolin containing protein.

Varicocele and testicular cord torsion: immune testicular microenvironment imbalance

The main functions of the testis, steroidogenesis and spermatogenesis, depend on the endocrine axis and systemic and local tolerance mechanisms. Infectious or non-infectious diseases may disturb testicular immune regulation causing infertility. Literature has illustrated that bacterial and viral infections lead to autoimmune infertility: either sperm antibodies or autoimmune epidydimo-orchitis. However, little is known about the association between non-infectious testicular pathologic diseases and autoimmunity. Here we review the novel aspect of varicocele and testicular cord torsion pathology linked to inflammation and discuss how immune factors could contribute to or modulate autoimmunity in ipsi- and contralateral testis.

Positive Effects of the Nutraceutical Association of Lycopene and Selenium in Experimental Varicocele

Many natural substances commonly found in healthy diets have been studied for their potential to reduce male infertility associated with varicocele. A positive role of selenium (Se) or lycopene alone was demonstrated in experimental varicocele, while no data are available on their association. One group of male Sprague-Dawley rats was sham operated and daily treated with Se (3 mg/kg, i.p.), lycopene (1 mg/kg, i.p.), or their association. A second group underwent surgery to induce varicocele. Sham and half of the varicocele animals were sacrificed after twenty-eight days, while the residual animals were treated for one more month and then sacrificed. In varicocele animals, testosterone levels and testes weight were reduced, Hypoxia Inducible Factor-1α (HIF-1α) expression was absent in the tubules and increased in Leydig cells, caspare-3 was increased, seminiferous epithelium showed evident structural changes, and many apoptotic germ cells were demonstrated with TUNEL assay. The treatment with lycopene or Se alone significantly increased testis weight and testosterone levels, reduced apoptosis and caspase-3 expression, improved the tubular organization, decreased HIF-1α positivity of Leydig cells, and restored its tubular positivity. Lycopene or Se association showed a better influence on all biochemical and morphological parameters. Therefore, the nutraceutical association of lycopene plus Se might be considered a possible therapeutic tool, together with surgery, in the treatment of male infertility. However, long-term experimental and clinical studies are necessary to evaluate sperm quantity and quality.

Exploring the mechanisms of Gui Zhi Fu Ling Wan on varicocele via network pharmacology and molecular docking

Varicocele (VC) is a common urogenital disease that leads to a high risk of testicular pain or male infertility. The purpose of this research was to explore the molecular mechanism of the Gui Zhi Fu Ling Wan (GFW) in the treatment of VC. The main active ingredients and targets information of GFW were screened by Traditional Chinese Medicine Systems Pharmacology (TCMSP) database, and the targets related to VC were determined by GeneCards, Online Mendelian Inheritance in Man (OMIM), and Disease Gene Network (DisGeNET) databases. The intersection of active ingredient targets and disease targets was selected to construct a protein-protein interaction (PPI) network through the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) database. Based on the use of CytoNCA plug-in to find the main targets, a 'component-target-disease' network was constructed by Cytoscape 3.8.2. Metascape was used for Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses of drug and disease targets. Molecular docking was employed to investigate the binding interaction between the main active components and core targets. A total of 76 active components of GFW were screened out. The main targets of the active components on VC were tumour protein p53 (TP53), tumour necrosis factor (TNF), hypoxia inducible factor 1 subunit alpha (HIF1A), interleukin-6 (IL-6), caspase 3 (CASP3), catalase (CAT), prostaglandin-endoperoxide synthase 2 (PTGS2), vascular endothelial growth factor A (VEGFA). The PI3K-Akt signalling pathway, HIF-1 signalling pathway, and apoptosis signalling pathway were mainly involved in the regulation of VC. The results of molecular docking showed that the binding potential and activity of the main active components and the core targets of GFW were good. We found that GFW could alleviate apoptosis, participate in venous vessel morphogenesis, and reduce oxidative stress in the treatment of VC. This study can provide a reference for subsequent clinical and scientific research experiments, which can be used to design new drugs and develop new therapeutic instructions to treat VC.

Effects of Environmental and Pathological Hypoxia on Male Fertility

Male infertility is a widespread health problem affecting approximately 6%-8% of the male population, and hypoxia may be a causative factor. In mammals, two types of hypoxia are known, including environmental and pathological hypoxia. Studies looking at the effects of hypoxia on male infertility have linked both types of hypoxia to poor sperm quality and pregnancy outcomes. Hypoxia damages testicular seminiferous tubule directly, leading to the disorder of seminiferous epithelium and shedding of spermatogenic cells. Hypoxia can also disrupt the balance between oxidative phosphorylation and glycolysis of spermatogenic cells, resulting in impaired self-renewal and differentiation of spermatogonia, and failure of meiosis. In addition, hypoxia disrupts the secretion of reproductive hormones, causing spermatogenic arrest and erectile dysfunction. The possible mechanisms involved in hypoxia on male reproductive toxicity mainly include excessive ROS mediated oxidative stress, HIF-1α mediated germ cell apoptosis and proliferation inhibition, systematic inflammation and epigenetic changes. In this review, we discuss the correlations between hypoxia and male infertility based on epidemiological, clinical and animal studies and enumerate the hypoxic factors causing male infertility in detail. Demonstration of the causal association between hypoxia and male infertility will provide more options for the treatment of male infertility.

Expression of Hypoxia-Inducible Factor1-α in Varicocele Disease: a Comprehensive Systematic Review

Hypoxia has been suggested as an important pathophysiological feature in varicocele disease. On the other hand, the expression of hypoxia-inducible factor 1-alpha (HIF1-α) is associated with the incidence of hypoxia. In this study, we investigated the expression of HIF1-α in varicocele disease through a comprehensive systematic review. We searched PubMed, Scopus, Web of Science, and Embase databases to identify the related studies published up to February 2021. Human studies have demonstrated an increase in the HIF-1α protein expression in the internal spermatic vein (ISV) of the varicocele testicle. HIF-1α mRNA expression in the seminal plasma was significantly higher in infertile varicocele patient compared with fertile ones. Similarly, most animal studies demonstrated a significant increase in HIF-1α gene and protein expression in varicocele testicular tissue compared with control groups. The studies illustrated that hypoxia followed by increased expression of hypoxia-inducible factor 1-alpha (HIF1-α) mRNA and protein occurs in varicocele disease. Expression of HIF-1α regulates the expression of many genes, including VEGF, p53, GLUT, Bax, and Caspase-3, that could be involved in many of the varicocele pathophysiological effects such as DNA fragmentation and apoptosis of sperm cells. Further studies with a large number of patients are necessary and can provide more definitive evidence.

Effects of HIF-1α on Spermatogenesis of Varicocele Rats by Regulating VEGF/PI3K/Akt Signaling Pathway

Hypoxia-inducible factor-1α (HIF-1α) participates in the regulation of spermatogenic function in rats with varicocele (VC), and the PI3K/Akt pathway plays an important role in it. In the present research, we applied the CRISPR/Cas9 gene editing technique to silence the HIF-1α gene of VC rat testis, to explore the effect of HIF-1α on apoptosis of spermatogenic cells in VC rats through the PI3K/Akt pathway. Sprague Dawley rats were randomly assigned to four groups, including the normal rat group (group N), VC model group (group V), VC + HIF-1α-lentivirus group (group H), and VC + luciferase-lentivirus group (group L). Apoptosis of spermatogenic cells in rat testis was tested by TUNEL Kit. The morphologic changes of seminiferous tubules were viewed by a light microscope. Expressions of VEGF, Akt, p-Akt, p70S6K, and p-p70S6K were detected by means of Western blot, immunofluorescence, or immunohistochemistry methods. One-way ANOVA was applied to analyze the diverseness between groups. Compared with group N, the distribution of germ cells was disordered, apoptosis of spermatogenic cells increased significantly, and the expression of VEGF, p-Akt, and p-p70S6K was also increased in group V. Compared with group V, the damage of seminiferous epithelium in group H was improved, and the arrangement of the seminiferous epithelium was almost orderly. Apoptosis of spermatogenic cells decreased significantly, and the expression of VEGF, p-Akt, and p-p70S6K protein was decreased (P < 0.05). There was no significant difference between group N and group H (P > 0.05).In conclusion, HIF-1α is regulated by hypoxia in rats with varicocele to regulate its downstream gene VEGF which regulates spermatogenesis, and the PI3K/Akt signaling pathway plays a regulatory role in this process.

Down regulating PHGDH affects the lactate production of sertoli cells in varicocele

BACKGROUND

Although varicocele is considered to be one of the leading causes of male infertility, the precise mechanism underlying how varicocele leads to male infertility is not completely understood. We found the lactate concentration on the varicocele side of the patients was decreased compare with peripheral venous blood. In the testicles, the lactate produced by the sertoli cells through the glycolysis pathway provides most of the energy needed for spermatogenesis, the reduction of lactate will affect spermatogenesis. The objective of this study was to investigate the mechanism of this abnormal energy metabolism phenomenon in varicocele.

METHODS

In this study, we collected the testicular tissue from patients with varicocele, the glycolysis related proteins PHGDH was identified by iTRAQ proteomics technology. Experimental rat varicocele model was constructed according to our new clip technique, the mRNA and protein expression levels of PHGDH were examined with qRT-PCR and Western blotting. We constructed a sertoli cell of PHGDH down-regulation model, and then detected the glucose consumption, LDH activities and lactate production in the sertoli cells. Western blot was conducted to investigate the effects of PHGDH on the expression of phosphoserine phosphatase (PSPH) and Pyruvate kinase M2 (PKM2). Flow cytometry was used to detect the cell apoptosis and cell cycle in sertoli cells.

RESULTS

The results showed that testicular protein PHGDH was down-regulated in patients with varicocele and in experimental rat varicocele model. Down-regulation of PHGDH in sertoli cells significantly decreased the glucose consumption, LDH activities and lactate production in the sertoli cells, indicating that the low expression of PHGDH ultimately led to a decrease in lactate production by affecting the glycolysis. The Western blot results showed that the down-regulation of PHGDH significantly reduced the expression of pathway protein PSPH and PKM2, leading to the reduction of lactate production. Moreover, PHGDH knockdown can promote apoptosis and inhibit cell cycle to affect cell growth.

CONCLUSIONS

Overall, we conformed that varicocele lead to the decreasing of testis lactate production. Down-regulation of PHGDH in sertoli cells may mediate the process of abnormal glucose metabolism. Our study provide new insight into the mechanisms underlying metabolism-associated male infertility and suggests a novel therapeutic target for male infertility.

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.

Identification and verification of key genes 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 rat model by surgery, analysed the rat epididymal spermatozoa and used the transcriptome sequencing to compare all the mRNA expression differences in testicular tissue between VC rats and control rats. The differentially expressed genes (DEGs) of testicular tissue were also screened by the limma package in R software (version 3.6.1). The 273 DEGs were identified from the four profile data sets including 124 up-regulated genes and 149 down-regulated genes in the VC group compared to control group. We found that Sod1, Casp9, Atg7, Casp3 and Sirt1 in module 1 had higher degrees of connectivity in the first 10 hub genes. Gene ontology (GO) functional enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis demonstrated that Sod1, Casp9, Atg7, Casp3 and Sirt1 are enriched in regulation of oxidative stress-induced cell death (GO:1,903,201) and Amyotrophic lateral sclerosis (KEGG:05,014). From the above evidence, we speculate that hypoxia plays an important role in the occurrence and development of VC, and it induced the abnormal expression of autophagy and apoptosis-related proteins may involve in the development of VC-associated infertility. Sod1, Casp9, Atg7, Casp3 and Sirt1 as well as their module are hub genes for VC, which will have attractive applications to provide new treatment targets for VC.

Signs of ROS-Associated Autophagy in Testis and Sperm in a Rat Model of Varicocele

Since autophagy was suspected to occur in the pathological situation of varicocele (VCL), we have attempted to confirm it here using a surgical model of varicocele-induced rats. Thirty Wistar rats were divided into three groups (varicocele/sham/control) and analyzed two months after the induction of varicocele. Testicular tissue sections and epididymal mature sperm were then monitored for classic features of varicocele, including disturbance of spermatogenesis, impaired testicular carbohydrate and lipid homeostasis, decreased sperm count, increased sperm nuclear immaturity and DNA damage, oxidative stress, and lipid peroxidation. At the same time, we evaluated the Atg7 protein content and LC3-II/LC3-1 protein ratio in testis and mature sperm cells, two typical markers of early and late cellular autophagy, respectively. We report here that testis and mature sperm show higher signs of autophagy in the varicocele group than in the control and sham groups, probably to try to mitigate the consequences of VCL on the testis and germ cells.

Melatonin Relations with Energy Metabolism as Possibly Involved in Fatal Mountain Road Traffic Accidents

Previous results evidenced acute exposure to high altitude (HA) weakening the relation between daily melatonin cycle and the respiratory quotient. This review deals with the threat extreme environments pose on body time order, particularly concerning energy metabolism. Working at HA, at poles, or in space challenge our ancestral inborn body timing system. This conflict may also mark many aspects of our current lifestyle, involving shift work, rapid time zone crossing, and even prolonged office work in closed buildings. Misalignments between external and internal rhythms, in the short term, traduce into risk of mental and physical performance shortfalls, mood changes, quarrels, drug and alcohol abuse, failure to accomplish with the mission and, finally, high rates of fatal accidents. Relations of melatonin with energy metabolism being altered under a condition of hypoxia focused our attention on interactions of the indoleamine with redox state, as well as, with autonomic regulations. Individual tolerance/susceptibility to such interactions may hint at adequately dealing with body timing disorders under extreme conditions.

Does varicocelectomy improve semen in men with azoospermia and clinically palpable varicocele?

The effectiveness of varicocelectomy in nonobstructive azoospermia is controversial. The current study assessed the efficacy of microsurgical subinguinal varicocelectomy in nonobstructive azoospermic men with palpable varicocele and to evaluate predictive parameters of outcome. We reviewed the records of 723 patients who had microsurgical varicocelectomy and diagnostic testicular biopsy between 2012 and 2016 at a tertiary medical centre. Data pertaining to the physical, laboratory (semen analysis and hormonal profile) and histopathology features were examined, exploring the predictors of improvement in semen analysis post-varicocelectomy. In total, 42 patients with mean age 35.71 ± 6.35 years were included. After a mean varicocelectomy follow-up of 6.7 months, motile spermatozoa in the ejaculate could be observed in 11 patients (26.2). Out of all the factors examined, only testicular histopathology significantly predicted post-varicocelectomy outcome, where 8/11 patients exhibited hypospermatogenesis, and 3/11 Sertoli cell-only regained spermatozoa in semen. Microsurgical varicocelectomy in nonobstructive azoospermic men with clinically palpable varicocele can result in sperm appearance in the ejaculate with the highest success expected in hypospermatogenesis.

A predicted risk score based on the expression of 16 autophagy-related genes for multiple myeloma survival

Autophagy has an important role in the pathogenesis of plasma cell development and multiple myeloma (MM); however, the prognostic role of autophagy-related genes (ARGs) in MM remains undefined. In the present study, the expression profiles of 234 ARGs were obtained from a Gene Expression Omnibus dataset (accession GSE24080), which contains 559 samples of patients with MM analyzed with 54,675 probes. Univariate Cox regression analysis identified 55 ARGs that were significantly associated with event-free survival of MM. Furthermore, a risk score with 16 survival-associated ARGs was developed using multivariate Cox regression analysis, including ATIC, BNIP3L, CALCOCO2, DNAJB1, DNAJB9, EIF4EBP1, EVA1A, FKBP1B, FOXO1, FOXO3, GABARAP, HIF1A, NCKAP1, PRKAR1A and SUPT20H, was constructed. Using this prognostic signature, patients with MM could be separated into high- and low-risk groups with distinct clinical outcomes. The area under the curve values for the receiver operating characteristic curves were 0.740, 0.741 and 0.712 for 3, 5 and 10 years prognosis predictions, respectively. Notably, the prognostic role of this risk score could be validated with another four independent cohorts (accessions: GSE57317, GSE4581, GSE4452 and GSE4204). In conclusion, ARGs may serve vital roles in the progression of MM, and the ARGs-based prognostic model may provide novel ideas for clinical applications in MM.

Cut-off values of the Johnsen score and Copenhagen index as histopathological prognostic factors for postoperative semen quality in selected infertile patients undergoing microsurgical correction of bilateral subclinical varicocele

Background

It remains challenging to determine which individuals are likely to benefit from microsurgical correction of subclinical varicocele, as basic semen parameters often do not improve postoperatively. We aimed to develop an easily accessible tool for prognostic stratification of infertile men indicated for microsurgical correction of bilateral subclinical varicocele characterized by prolonged and clear venous reflux and no other cause for infertility.

Methods

We retrospectively analyzed the testicular biopsy, seminal analysis, and ultrasound evaluation records of 20 men managed between 2006 and 2014. Subclinical varicocele was diagnosed through bilateral testicular palpation and auscultation of venous reflux using a Doppler stethoscope, with confirmation on color Doppler sonography. We conducted receiver operating characteristic curve analysis to identify the optimal combinations of cut-offs for the Johnsen score, Copenhagen index, and testicular volume defining histological patterns with positive prognostic value for improved postoperatively reproductive capacity.

Results

Positive prognostic value was noted for the following combinations of parameters: (I) Johnsen score >8.2 in the left testicle and right testicular volume >12.8 mL predicted improved sperm concentration; (II) Johnsen score >8.2 and Copenhagen index digit II <2.5 bilaterally predicted improved total sperm motility; (III) Johnsen score >9.1 and Copenhagen index digit III <1.5 bilaterally predicted improved progressive sperm motility; (IV) Johnsen score >7.9 and right testicular volume >13.6 mL predicted improved sperm morphology.

Conclusions

Johnsen score and Copenhagen index as histopathological prognostic factors can be easily obtained upon evaluation of testicular biopsy specimens and can be simple and reliable tool to establish a more realistic prognosis for reproductive capacity in men who undergo microsurgical correction of subclinical varicocele with no other detectable cause for infertility.

GYY4137 a H2S donor, attenuates ipsilateral epididymis injury in experimentally varicocele-induced rats via activation of the PI3K/Akt pathway

OBJECTIVES

The current study was aimed to investigate the effect of morpholin-4-ium 4 methoxyphenyl (morpholino) phosphinodithioate (GYY4137) on ipsilateral epididymis injury in a rat model of experimental varicocele (VC).

MATERIALS AND METHODS

Sixty Wistar rats were randomly assigned to sham, sham plus GYY4137, VC and VC plus GYY4137 groups. Sperm quality parameters, including sperm count, motility and viability were evaluated after 4 weeks. Histological changes were measured by hematoxylin and eosin staining between the groups. The oxidative stress levels were estimated by determining epididymal superoxide dismutase (SOD) and malondialdehyde (MDA). The apoptosis status and the expression of phosphatidylinositol 3'-OH kinase (PI3K)/Akt were analyzed by immunohistochemical analysis, western blot and RT-qPCR.

RESULTS

VC resulted in the decrease of sperm parameters, significant histological damage and higher levels of oxidative stress and apoptosis. Compared to the VC group, GYY4137 markedly ameliorated these observed changes. In addition, treatment with GYY4137 obviously reduced the levels of caspase-3 and Bax and increased the levels of the phosphorylation of PI3K p85 and Akt.

CONCLUSION

Our data demonstrated that GYY4137 may alleviate the sperm damage and epididymis injury in experimentally VC-induced rats by activation of the PI3K/Akt pathway.

Effects of autophagy on the spermatogonia of chronic hypoxic mice

Varicocele (VC) is a common cause of male infertility. An increasing number of studies have confirmed that chronic hypoxia plays an important role in male infertility caused by VC. Our previous study suggested that autophagy may have a crucial function in VC. Whether autophagy plays an important role in hypoxic spermatogonia remains unknown. We established a new method to study VC by culturing spermatogonia under hypoxic conditions to simulate the chronic hypoxic environment of VC. Moreover, the effects of autophagy on hypoxic spermatogonia were observed by regulating autophagy. Spermatogonia from GC-1 spg mice were cultured in vitro in chronic hypoxic conditions (2% O₂, 93% N₂, 5% CO₂) with a tri-gas incubator. Cells were separately cultured under normal oxygen and hypoxic conditions, and then, the autophagy blocker drug LY294002 was subsequently administered. Cytoactivity and proliferation were tested by CCK8 assays. Cells cultured in hypoxic conditions were divided into the hypoxia for 24 h, 48 h, and 72 h groups and the LY294002+hypoxia for 24 h, 48 h, and 72 h groups. Hoechst staining and flow cytometry/Annexin-V-FITC/PI staining were used to detect cell apoptosis, while transmission electron microscopy was used to observe the structure of the spermatogonia. Western blot analysis was used to observe the expression of Hif-1α, Beclin-1, LC3, SOD2, GPX4, and Cyt C. As the hypoxia time increased, CCK8 detection showed that the cytoactivity of the spermatogonia was suppressed. After administration of the inhibitor LY294002, the inhibition ratio of the spermatogonia increased. As the hypoxia time was prolonged, the apoptosis index of spermatogonia increased. After administration of LY294002, the apoptosis index increased significantly. Transmission electron microscopy showed that there were abundant structurally abnormal mitochondria and autophagosomes and autolysosomes in hypoxic spermatogonia. In addition, LY294002 reduced the expression of autophagosomes and autophagosomes, but the number of abnormal mitochondria and vacuoles in hypoxic cells increased significantly. As the hypoxia time was prolonged, the expression levels of Hif-1α, Beclin-1, LC3 II/LC3-I, and Cyt C increased gradually, but there were no significant changes in SOD2 and GPX4. After administration of LY294002, the expression levels of Beclin-1, LC3 II/LC3-I, and GPX4 significantly decreased, but Cyt C significantly increased. Thus, chronic hypoxia decreases cytoactivity and proliferation of spermatogonia. Moreover, hypoxia damages the mitochondria and other organelles. At the same time, hypoxia activates the autophagic system to clear these damaged organelles. The inhibition of autophagy in spermatogonia under chronic hypoxic conditions prevents the removal of damaged mitochondria and eventually results in a significant decrease in the antioxidant system molecule GPX4, rather than SOD2, and a significant increase in the apoptosis rate.

Comparison of main molecular markers involved in autophagy and apoptosis pathways between spermatozoa of infertile men with varicocele and fertile individuals

Abnormal dilatation and tortuosity of the pampiniform plexus within the spermatic cord are termed varicocele which leads to impaired spermatogenesis due to heat-related oxidative stress and cell death. Previously, it was shown that both apoptosis and autophagy pathways were activated by heat in germ cells of mouse in vivo and in vitro. But, status of these pathways is not clear in chronic state of heat stress such as varicocele. Therefore, we aimed to access sperm apoptotic markers (active caspases 3/7 and DNA fragmentation), and autophagic markers (Atg7 and LC3 proteins) as primary outcomes, and also sperm parameters and protamine deficiency as secondary outcomes between 23 infertile men with varicocele and 16 fertile individuals. Sperm parameters were assessed according to World Health Organization 2010 protocol. Apoptotic markers (active caspases 3/7 and DNA fragmentation), autophagic markers (Atg7 and LC3 proteins), and protamine deficiency were evaluated by flow cytometry, fluorescence microscope, and western blotting techniques. Mean of autophagy and apoptosis markers, and also protamine deficiency have significantly increased in infertile men with varicocele compared to fertile individuals, but autophagy and apoptosis markers did not significantly correlate with each other. In conclusion, it seems that both apoptosis and autophagy pathways are independently active in spermatozoa of infertile men with varicocele.