Testicular Germ Cell Apoptosis Research Articles

P-044 Increased CYP1A1 expression enhances sperm apoptosis in idiopathic infertile men

Abstract Study question How are the CYP1A1 and Caspase-9 genes expression and the relationship among the expression of these genes with sperm parameters in idiopathic infertile men? Summary answer The CYP1A1 and Caspase-9 gene expression showed a significant increase in patients in comparison with the healthy group. What is known already CYP1A1 (Cytochrome P450 Family 1 Subfamily A Member 1) plays a crucial role in xenobiotic metabolism induced by aryl hydrocarbon receptor (AHR). AHR, as a ligand-activated transcription factor is involved in exogenous ligand activation. CYP1A1 is one of the most essential enzymes in phase 1 of detoxification, metabolism, and bio-activation of carcinogens and is the most well-known target gene for AHR. Monooxygenase activity of CYP1A1 may lead to oxidative stress and the formation of reactive intermediates with destructive effects such as apoptosis in testicular germ cells. CYP1A1 may lead to apoptosis via Caspase-9 activation. Study design, size, duration In this study, we aimed to determine the CYP1A1 and Caspase-9 gene expression. Participants/materials, setting, methods The infertile idiopathic and healthy fertile men were selected and evaluated for sperm analysis and gene expression. The expression levels of CYP1A1 and Caspase-9 were also determined by real time PCR. Main results and the role of chance The sperm count, morphology and motility were significantly lower in patients compared to the control group (p < 0.05). The CYP1A1 and Caspase-9 gene expression showed a significant increase in patients in comparison with the healthy group (p < 0.05). Limitations, reasons for caution Further investigations of the effect of CYP1A1 and Caspase-9 expressions on infertility by using more infertile patients and also studying the effect of other important genes such as AHR can show us more accurate results. Wider implications of the findings Our results suggest that increased CYP1A1 and Caspase-9 expression could increase the rate of male infertility. In addition, the increase in Caspase-9 expression could lead to a reduced number of sperms and an increased infertility rate by increased apoptosis in the spermatogenic lineage. Trial registration number not applicable

Lats1 and Lats2 regulate YAP and TAZ activity to control the development of mouse Sertoli cells.

Recent reports suggest that the Hippo signaling pathway regulates testis development, though its exact roles in Sertoli cell differentiation remain unknown. Here, we examined the functions of the main Hippo pathway kinases, large tumor suppressor homolog kinases 1 and 2 (Lats1 and Lats2) in developing mouse Sertoli cells. Conditional inactivation of Lats1/2 in Sertoli cells resulted in the disorganization and overgrowth of the testis cords, the induction of a testicular inflammatory response and germ cell apoptosis. Stimulated by retinoic acid 8 (STRA8) expression in germ cells additionally suggested that germ cells may have been preparing to enter meiosis prior to their loss. Gene expression analyses of the developing testes of conditional knockout animals further suggested impaired Sertoli cell differentiation, epithelial-to-mesenchymal transition, and the induction of a specific set of genes associated with Yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ)-mediated integrin signaling. Finally, the involvement of YAP/TAZ in Sertoli cell differentiation was confirmed by concomitantly inactivating Yap/Taz in Lats1/2 conditional knockout model, which resulted in a partial rescue of the testicular phenotypic changes. Taken together, these results identify Hippo signaling as a crucial pathway for Sertoli cell development and provide novel insight into Sertoli cell fate maintenance.

Responses of peritubular macrophages and the testis transcriptome profiles of peripubertal and adult rodents exposed to an acute dose of MEHP.

Exposure of rodents to mono-(2-ethylhexyl) phthalate (MEHP) is known to disrupt the blood-testis barrier and cause testicular germ cell apoptosis. Peritubular macrophages (PTMφ) are a newly identified type of testicular macrophage that aggregates near the spermatogonial stem cell niche. We have previously reported that MEHP exposure increased the numbers of PTMφs by 6-fold within the testis of peripubertal rats. The underlying mechanism(s) accounting for this change in PTMφs and its biological significance is unknown. This study investigates if MEHP-induced alterations in PTMφs occur in rodents (PND 75 adult rats and PND 26 peripubertal mice) that are known to be less sensitive to MEHP-induced testicular toxicity. Results show that adult rats have a 2-fold higher basal level of PTMφ numbers than species-matched peripubertal animals, but there was no significant increase in PTMφ numbers after MEHP exposure. Peripubertal mice have a 5-fold higher basal level of PTMφ compared with peripubertal rats but did not exhibit increases in number after MEHP exposure. Further, the interrogation of the testis transcriptome was profiled from both the MEHP-responsive peripubertal rats and the less sensitive rodents via 3' Tag sequencing. Significant changes in gene expression were observed in peripubertal rats after MEHP exposure. However, adult rats showed lesser changes in gene expression, and peripubertal mice showed only minor changes. Collectively, the data show that PTMφ numbers are associated with the sensitivity of rodents to MEHP in an age- and species-dependent manner.

The role of death receptor signaling pathways in mouse Sertoli cell avoidance of apoptosis during LPS- and IL-18-induced inflammatory conditions

Lipopolysaccharide (LPS) triggers infectious acute inflammation, and interleukin (IL)-18 is an inflammasome-mediated cytokine. We previously demonstrated that endogenous IL-18 induces testicular germ cell apoptosis during acute inflammation when plasma IL-18 levels are high. Additionally, high-dose recombinant IL-18 (rIL-18) induced Leydig cell apoptosis. The blood-testis barrier formed by Sertoli cells protects testicular germ cells from both exogenous and endogenous harmful substances. However, the impact of LPS and IL-18 on Sertoli cells remained unclear. We stimulated TM4 cells, a mouse Sertoli cell line, with LPS (200 or 1000 ng/mL) or rIL-18 (0.1–100 ng/mL) at levels that induced Leydig cell apoptosis in our previous study and assessed caspase 3 cleavage and the mRNA expression of inflammatory cytokines and markers of apoptotic pathways (Tnfr1, Fasl, Fas, Fadd) after stimulation. Il6 mRNA was increased by LPS stimulation. Tnfα mRNA was increased by 200 ng/mL LPS but not 1000 ng/mL LPS. Fas was increased, but Fasl was decreased, by LPS. LPS had little influence on Tnfr1 or Fadd mRNA expression and did not induce apoptosis. Il18 mRNA was not increased, and Il18r1 was significantly decreased following LPS treatment. Treatment with rIL-18 increased Il18r1 mRNA and induced inflammation, but decreased Tnfr1 and had little influence on apoptosis, as indicated by Tnfα, Fasl, Fas, Fadd and cleaved caspase 3. These results suggested that Sertoli cells do not easily undergo apoptosis despite strong inflammatory stimuli. Additionally, Sertoli cells may resist inflammation and play a larger role in protecting testicular homeostasis than other component cells of the testis.

Long-term consumption of fermented pork fat-based diets differing in calorie, fat content, and fatty acid levels mediates oxidative stress, inflammation, redox imbalance, germ cell apoptosis, disruption of steroidogenesis, and testicular dysfunction in Wistar rats.

There is a dearth of experimental evidence available as to whether the consumption of fermented pork fat (FPF) food has any harmful effects on metabolism and reproduction due to its excessive calories, high fat content, and fatty acid methyl ester (FAME) levels. We hypothesized that exposure to a FPF-diet with excessive calories, a high fat content, and high FAME levels alters testicular physiology and metabolism, leading to permanent damage to the testicular system and its function. Thirteen-week-old male rats (n = 20) were assigned to a high-calorie, high-fat diet (FPF-H, fat-60%, 23kJ/g), a moderate-calorie, moderate-fat diet (FPF-M, fat-30%, 17.5kJ/g), a low-calorie and low-fat diet (FPF-L, fat-15%, 14.21kJ/g) compared to the standard diet (Control, fat-11%, 12.56kJ/g) orally for 90days. GC-MS analysis of the three FPF-diets showed high quantities of saturated fatty acids (SFAs) and polyunsaturated fatty acids-ω6 (PUFA-ω6) and low levels of monounsaturated fatty acids (MUFAs) and polyunsaturated fatty acids-ω3 (PUFA-ω3) compared to the control diet. Consequently, the levels of serum FAMEs of the FPF-diet fed rats were significantly increased. In addition, a high level of n-6:n-3 PUFA towards PUFA-ω6 was observed in the serum of FPF-diet fed rats due to the high content of linoleic, γ-linolenic, and arachidonic acid. Long-term consumption of FPF-diets disturbed the anthropometrical, nutritional, physiological, and metabolic profiles. Furthermore, administration of FPF-diets generated metabolic syndrome (dyslipidemia, leptinemia, insulin resistance, obesity, hepato-renal disorder and function), increased the cardiovascular risk factors, and triggered serum and testis inflammatory markers (interleukin-1↑, interleukin-6↑, interleukin-10↓, leukotriene B4↑, prostaglandin↑, nitric oxide↑, myeloperoxidase↑, lactate dehydrogenase↑, and tumor necrosis factor-α↑). Activated testis oxidative stress (conjugated dienes↑, lipid hydroperoxides↑, malondialdehyde↑, protein carbonyl↑, and fragmented DNA↑) and depleted antioxidant reserve (catalase↓, superoxide dismutase↓, glutathione S-transferase↓, reduced glutathione↓, glutathione disulfide↑, and GSH:GSSG ratio↓) were observed in FPF-diet fed rats. Disrupted testis histoarchitecture, progressive deterioration of spermatogenesis, poor sperm quality and functional indices, significant alterations in the reproductive hormones (serum and testis testosterone↓, serum estradiol↑, serum luteinizing hormone↓, and follicle-stimulating hormone↑), were noted in rats fed with FPF diets than in the control diet. Severe steroidogenic impairment (steroidogenic acute regulatory protein, StAR↓; 3β-hydroxysteroid dehydrogenase, 3β-HSD↓; and luteinizing hormone receptor, LHR↓), deficiency in germ cells proliferation (proliferating cell nuclear antigen, PCNA↓), and abnormally enhanced testicular germ cell apoptosis (terminal deoxynucleotidyl transferase dUTP nick end labeling, TUNEL assay↑; B-cell lymphoma-2, BCL-2↓; Bcl-2-associated X protein, BAX↑; and BAX/BCL-2 ratio↑) were remarked in the FPF-diet administered rats in comparison with the control diet. In conclusion, the long-term feeding of an FPF-diet with excessive calories, a high fat content, and high FAME levels induced oxidative stress, inflammation, and apoptosis, resulting in metabolic syndrome and hampering male reproductive system and functions. Therefore, the adoption of FPF diets correlates with irreversible changes in testis metabolism, steroidogenesis, germ cell proliferation, and apoptosis, which are related to permanent damage to the testicular system and function later in life.

Is losartan a promising agent for the treatment of type 1 diabetes-induced testicular germ cell apoptosis in rats?

Diabetes mellitus (DM) is common metabolic disease that poses a major risk to public health and fertility. Previous studies indicate that DM may cause male infertility by triggering oxidative stress and germ cell apoptosis in the testis. Due to the undesirable effects of known antidiabetic drugs, scientists have begun to investigate the use of alternative drugs to control infertility complications observed in men. In this context, present study aimed to investigate the possible antiapoptotic effect of losartan against DM-induced testicular germ cell apoptosis. Expreimental DM model was induced by intraperitoneal injection of streptozocin (STZ, 55mg/kg) to 28 rats, which were then randomly assigned to 4 groups; 1 mL saline solution was given to DM + saline group by oral gavage, 5mg/kg/day oral losartan was given to DM + low-dose losartan, 20mg/kg/day oral losartan was given to DM + mid-dose losartan and, 80mg/kg/day oral losartan was given to DM + high-dose losartan group for 4 weeks. Bax, Bcl-2 and cleaved-Caspase 3 immunoexpression, terminal-deoxynucleotidyl transferase dutp nick end labeling (TUNEL), Annexin-V and Real Time PCR analyses performed to evaluate antiapoptotic effects of losartan on diabetic rats' testis. In addition, biochemical analyzes carried out to evaluate change in oxidative stress. The results showed that losartan may have dose-related antiapoptotic effects on rats' testis via decreasing oxidative stress.

Hadh deficiency induced oligoasthenoteratozoospermia through the TNF-α/Bcl-2 pathway in male mice.

The process of spermatogenesis is a complex and delicate process that is still not fully understood. In this study, we examined the role of fatty acid oxidase 3-hydroxy acyl CoA dehydrogenase (HADH) in maintaining normal spermatogenesis in mice. In male mice, ablation of the Hadh gene using CRISPR/Cas9 technology arrested spermatocyte meiosis, increased multinucleated giant germ cells and vacuoles in seminiferous tubules, and accompanied with acrosomal dysplasia. Hadh-/- male mice showed the typical features of oligoasthenoteratozoospermia (OAT), including decreased sperm concentration and motility and increased sperm abnormalities. Next, we explored the molecular events in the testes of the mutant mice. We found fatty acids accumulated in the testis of Hadh-/- mice. And also, inflammatory factors TNF-α, IL-1β, and IL-6 were significantly increased, apoptosis-related protein Bcl-2 was decreased, and Bax and cleaved-Caspase3 were increased in Hadh-/- male mice testis. After using etanercept, a specific inhibitor of TNF-α, testis injury caused by Hadh knockout was significantly alleviated, the sperm quality and motility were improved, and germ cell apoptosis was reduced. So our study demonstrated that Hadh deletion caused an increase in fatty acids. The accumulated fatty acids further induced testicular inflammation and germ cell apoptosis through the TNF-α/Bcl-2 signaling pathway, finally resulting in OAT in the Hadh-/- mice. Inhibiting TNF-α may be used as a new treatment approach for testicular inflammation and OAT.

Lrriq1 is an essential factor for fertility by suppressing apoptosis.

Leucine-rich repeats and IQ motif containing 1 (LRRIQ1) gene is reportedly associated with plasma inhibin B levels. However, the function of LRRIQ1 remains unknown. In this study, we generated Lrriq1 knockout mice (Lrriq1-/- mice) and examined the effects of LRRIQ1 on inhibin B and fertility. Lrriq1-/- mice were generated using CRISPR/Cas9 genome editing technology. The expression of Inhibin B was examined by Western blotting using a protein extracted from the testis of a 3-month-old male mouse. Mating experiments were conducted using 7-week-old Lrriq1-/- mice and wild-type (WT) mice to examine fertility. Sperm concentration and sperm motility were measured using 3-month-old male mice. Expression analysis of inhibin B revealed that Lrriq1-/- mice exhibited reduced mRNA and protein levels of inhibin alpha (Inha), which constitutes the α subunit. In the mating experiment, the litter size of Lrriq1-/- male mice was 4.3 ± 2.9, which was significantly lower than that of WT male mice (8.3 ± 1.3) (p < 0.001). No difference in sperm count was observed between Lrriq1-/- and WT male mice; however, sperm motility (%) was significantly reduced in Lrriq1-/- mice (48.4 ± 4.9) when compared with WT mice (70.2 ± 4.7) (p < 0.001). Based on TUNEL staining, the testes and epididymal sperm of Lrriq1-/- mice showed high numbers of apoptosis-positive cells. Lrriq1 knockout reduced sperm motility and litter size by inducing apoptosis of testicular germ cells and epididymal sperm.

Effect of low energy shock wave on testicular microenvironment homeostasis in rats

ObjectiveTo further investigate whether two sets of low-energy extracorporeal shock waves (LESWs) impulse parameters, i.e., 0.02 mJ/mm2 for 500 impulses and 0.04 mJ/mm2 for 500 impulses, which have been shown to directly affect the testes, can promote testicular spermatogenesis or positively regulate homeostasis of the testicular microenvironment. Methods(1) Twenty-four experimental rats were randomly divided into a 0.02 mJ/mm2 500 impulses group (L1 group), a 0.04 mJ/mm2 500 impulses group (M1 group), a sham intervention group (S group) and a blank control group (N group). The experiment period was 8 weeks. (2) Apoptosis of the spermatogenic cells in the left testicle was detected by the TUNEL method, VEGF and eNOs protein expression was detected by immunohistochemistry, and histomorphological changes were observed in PAS-stained sections. Moreover, the morphologies of the spermatogenic tubules and testicular stroma were quantitatively analyzed by stereological analysis. The right testicle was used for Western blot detection of the protein expression levels of Bax, Cytochrome C, Caspase-3, Bcl-2, VEGF and eNOs. ResultsCompared with the other three groups, the rate of M1 testicular germ cell apoptosis induced by shock treatment was higher, the expression levels of proapoptotic proteins increased significantly while that of the antiapoptotic protein was lower, and the suppression of cell proliferation correlated with the protein expression levels. Additionally, with respect to the absolute volume of the seminiferous tubules, the absolute interstitial testicular volume notably increased, producing a series of biological effects working against testicular sperm production and function. However, there was no significant difference between the L1 group and the N and S groups. ConclusionsLESWs treatment with impulse parameters of 0.02 mJ/mm2 for 500 impulses showed a better protective effect on testicular spermatic function in rats and has a positive regulatory biological effect.

High-fat diet aggravates prenatal low-dose DEHP exposure induced spermatogenesis disorder: Characterization of testicular metabolic patterns in mouse offspring

Di-(2-ethylhexyl) phthalate (DEHP) is a widely used plasticizer and has been identified as a male prenatal reproductive toxicant. A high fat diet (HFD) has also been suggested as another potential disruptor of male reproductive function. Despite this potential synergism between DEHP exposure and HFD, little is known about the concomitant effects of prenatal DEHP and a subsequent HFD exposure on male offspring reproductive injury. Here we established a mouse model of prenatal exposure to DEHP (0.2 mg/kg/day) to assess the testicular development and spermatogenesis in offspring subjected to obesogenic diet during the pubertal period. Gross phenotype, hormone profiles and the testicular metabolome were analyzed to determine the underlying mechanism. We found that prenatal exposure to low-dose DEHP resulted in decreased sperm density, decreased testosterone (T) levels, increased luteinizing hormone (LH) levels and testicular germ cell apoptosis. Furthermore, these injury phenotypes were aggravated by pubertal HFD treatment. Testicular riboflavin and biotin metabolites were enriched implying their roles in contributing HFD to exacerbate offspring spermatogenesis disorders due to prenatal low-dose DEHP exposure. Our findings suggest that pubertal HFD exacerbates reproductive dysfunction associated with prenatal exposure to low-dose DEHP in male adult offspring.

The protective effect of pumpkin seed oil on L-thyroxine-induced rat testicular oxidative stress

ObjectivesThis work aimed to study the effect of exogenously administered L-thyroxine on adult rat testis and to clarify the possible protective effect of pumpkin seed oil.BackgroundL-thyroxine is a manufactured form of the thyroid hormone thyroxine. It is used for the treatment of cases of thyroid hormone deficiency. Recently, infertility among men has become a major concern. Pumpkin is an annual herbaceous plant and has been safely used as a natural remedy in many countries. It has a wide range of pharmacological activities and a proposed antioxidant effect.Materials and methodsA total of 42 adult male albino rats were divided into the control group, pumpkin seed oil-treated group (4 ml/kg) orally for 10 days, L-thyroxine-treated group (0.3 mg/kg) intraperitoneal for 15 days, and both pumpkin seed oil and L-thyroxine-treated group. Specimens from the testes were processed for light microscopy. An immunohistochemical study was carried out using caspase 3.ResultsSpecimens from L-thyroxine-treated rats showed a statistically significant decrease in both tubular diameter and thickness of the epithelium of seminiferous tubules. Germinal epithelium showed cellular degeneration, vacuolated cytoplasm, and also there were apoptotic and multinucleated giant cells.The immunohistochemical study of the L-thyroxine-treated group showed intense positive caspase 3 immunostaining. In contrast, minimal changes were observed in rats treated concomitantly with both pumpkin seed oil and L-thyroxine-treated rats, with minimal change in immunoreaction compared with the control group.ConclusionExogenously administered L-thyroxine induced significant testicular damage and germ cell apoptosis, which could be ameliorated by concomitant treatment with pumpkin seed oil.

Efficacy of N-acetyl- l-cysteine against glyphosate induced oxidative stress and apoptosis in testicular germ cells preventing infertility.

The present era's demand for continuous pesticides' useto increase the agriculture outcome, has causednumerous health effects among which mammalian infertility, owing to reproductive toxicity, is serious. Thus, the present study emphasizes upon glyphosate (GLY) induced toxicity and mitigating effects of N-acetyl cysteine (NAC) in testicular cells of caprine by using various cytotoxic and biochemical parameters. GLY was found to induce several apoptotic attributes such as pyknotic nuclei, tubular degeneration, increased vacuolization, and so on, in testicular cells. GLY also decreased the cell viability and increased the incidence of apoptosis in testicular cells in a dose- and time-dependent manner as revealed by MTT assay and Fluorescence (ethidium bromide/acridine orange) assay, respectively. It also increased the level of oxidative stress as evident with an increase in lipid peroxidation and decline in antioxidant power along with the decreased enzymatic activity of different antioxidant enzymes (SOD, CAT, and GST). However, NAC supplementation showed antagonistic results in GLY-treated testicular tissues with maximum amelioration at the highest dose, therebydecreasing GLY-mediated apoptosis rate and oxidative stress. Maximum amelioration was reported at 10 mM NAC concentration. Reduced GLY toxicity due to NACwill prove NAC to be an excellent approach for dealing with male reproductive toxicity at the cellular level, benefiting the mammalian reproductive status.

Di-(2-ethylhexyl) phthalate induces testicular endoplasmic reticulum stress and germ cell apoptosis in adolescent mice.

Di-(2-ethylhexyl) phthalate (DEHP) is a male reproductive toxicant. This research is aimed at investigating the effect of pubertal DEHP exposure on testicular endoplasmic reticulum (ER) stress and germ cell apoptosis. Five-week-old male mice were orally administered with DEHP (0, 0.5, 50, or 500mg/kg/day) for 35 days. Testis weight and sperm count were reduced in mice exposed to 500mg/kg/day DEHP. The number of seminiferous tubules in stages VII-VIII, mature seminiferous tubules, was reduced and the number of seminiferous tubules in stages IX-XII, immature seminiferous tubules, was elevated in mice treated with 500mg/kg/day DEHP. Numerous apoptotic germ cells were observed in mouse seminiferous tubules exposed to 50 and 500mg/kg/day DEHP. Moreover, cleaved caspase-3 was elevated in mouse testes exposed to 500mg/kg/day DEHP. In addition, Bcl-2 was reduced and Bax/Bcl-2 was elevated in mouse testes exposed to 500mg/kg/day DEHP. Additional experiment showed that GRP78, an ER molecular chaperone, was downregulated in mouse testes exposed to 500mg/kg/day DEHP. Testicular p-IRE-1α, p-JNK, and CHOP, three markers of ER stress, were upregulated in mice exposed to 500mg/kg/day DEHP. These results suggest that pubertal exposure to high doses of DEHP induces germ cell apoptosis partially through initiating ER stress in testes.

Adaptogenic potential of royal jelly in reproductive system of heat stress-exposed male rats.

Testicular heat stress (HS) can lead to testicular tissue destruction and spermatogenesis disturbances. Royal Jelly (RJ) has been introduced as a potent antioxidant. We investigated the effects of RJ on testicular tissue, oxidative stress and sperm apoptosis in HS-exposed rats. Compared to HS-exposed groups, RJ co-treatment could improve testosterone reduction and histopathological damages. The RJ co-administration decreased MDA level in testicular tissue, while TAC and CAT levels were remarkably increased compared to HS-exposed groups. Moreover, significant higher expression level of Bcl-2 and lower expression levels of P53 and Caspase-3 were seen following RJ co-administration compared to HS-exposed groups. Our data suggest that RJ can effectively ameliorate experimental HS-induced testiculopathies in rats through testicular antioxidant defense system restoration and germ cells apoptosis regulation.

The effects of ozone and melatonin on busulfan-induced testicular damage in mice.

Objective:Busulfan is one of the most common chemotherapeutic drugs and has the ability to induce apoptosis in testicular germ cells, which leads to infertility. In this study, the effects of ozone therapy and melatonin were evaluated on testicular disorders induced by busulfan.Methods:In this study, we divided 24 male mice into four groups: control group, groups treated with busulfan, busulfan/melatonin, and busulfan/ozone. At the end of a 35-day period, blood samples were taken from the mice and their testosterone levels were measured. Both of the mice’s testes were removed and weighed, afterwards, each one of them was used for evaluation of morphology by Johnson’s score, as well as for measuring the diameter and thickness of seminiferous tubules. The other testis was homogenized for measuring Malondialdehyde (MDA) and antioxidant status using Catalase (CAT), Super Oxide Dismutase (SOD), and Total Antioxidant Capacity (TAC) levels. Epididymis spermatozoa were also used to evaluate motility, morphology, and sperm count.Results:Busulfan significantly reduced the testis quality (weight, sperm parameters, testosterone, CAT, SOD, and TAC levels) and increased MDA and destruction of seminiferous tubules compared to the control group. Ozone and melatonin treatments significantly increased testis quality, sperm parameters, MDA, and antioxidant status, but they did not affect the TAC level.Conclusions:This study showed that similar to melatonin, ozone can reduce the effect of busulfan toxicity on mice testis. However, further studies are needed to understand the precise mechanism of ozone function on testis.

Autophagy in Sertoli cell protects against environmental cadmium-induced germ cell apoptosis in mouse testes.

Cadmium (Cd) was an environmental pollutant, which could result in germ cell apoptosis in testes. Sertoli-germ cell communication was vital for germ cell development and maturity. However, little was known about the effect of Sertoli cell autophagy on Cd-induced germ cell apoptosis. Here, we used male Amh-Cre+/Atg5flox/flox (Atg5-/-) mice, loss of autophagy-related gene 5 (Atg5) in testicular Sertoli cells, to explore the obscure effects. Atg5-/- and Wild-type (WT) mice were given with cadmium chloride (CdCl2, 2.0mg/kg) for 0-24h. Our results showed that Cd triggered testicular germ cell apoptosis, as evidenced by the increment of TUNEL-labeled germ cells, cleaved caspase3 and cleaved poly (ADP-ribose) polymerase protein level. Additionally, Cd induced testicular autophagy, as determined by elevating the level of autophagy-related proteins, including Atg5, Atg7, LC3B-II, and the gathering of LC3 puncta. 3-methyladenine, a specific autophagy inhibitor, exacerbated Cd-caused germ cell apoptosis. Inversely, rapamycin, an autophagy inducer, relieved Cd-stimulated germ cell apoptosis. Interestingly, we found that autophagy in Sertoli cells was activated in Cd-treated WT mouse testes as evidenced by the increment of LC3 puncta surrounding SOX9, a specific Sertoli cell marker. More importantly, loss of autophagy in Sertoli cells aggravated Cd-triggered germ cell apoptosis. Taken together, these data indicate that autophagy in Sertoli cells alleviates Cd-triggered germ cell apoptosis in mouse testes.

Interleukin-18 levels and mouse Leydig cell apoptosis during lipopolysaccharide-induced acute inflammatory conditions

Interleukin (IL)-18 is an inflammasome-mediated cytokine produced by germ cells, Leydig cells, and resident macrophages that is indispensable in the maintenance of homeostasis in the testis. We previously demonstrated that endogenous IL-18 induces testicular germ cell apoptosis during acute inflammation when plasma IL-18 levels are very high. However, the impact of acute inflammation and IL-18 on Leydig cells remained unclear. TM3 cells, a mouse Leydig cell line, and RAW264.7 cells, a mouse macrophage cell line, were stimulated with lipopolysaccharide (LPS) or recombinant IL-18 (rIL-18). We assessed the expression of inflammatory cytokines, caspase cleavage, and markers of apoptotic pathways. In Leydig cells, caspase 3 cleavage was increased and death-receptor-mediated apoptotic pathways were activated after LPS stimulation. However, LPS stimulation did not increase IL-18 expression in the Leydig cell line. When high-dose rIL-18 was administered to the Leydig cell line to mimic levels seem after inflammation, rIL-18 upregulated Tnf-α mRNA, Fadd mRNA, and Fas protein, promoted cleavage of caspase-8 and caspase-3, and induced apoptosis. Low-dose rIL-18 did not stimulate apoptosis. To determine if the high level of IL-18 seen in the testes after inflammation was derived from immune cells, we examined IL-18 protein expression in a macrophage cell line, RAW264.7. In contrast to the TM3 cells, IL-18 was significantly increased in RAW264.7 cells after LPS stimulation. These results suggest that high-dose IL-18 derived from macrophages is harmful to Leydig cells. Reducing the overexpression of IL-18 could be a new therapeutic approach to prevent Leydig cell apoptosis as a result of acute inflammation.

The potential protective and therapeutic effects of platelet-rich plasma on ischemia/reperfusion injury following experimental torsion/detorsion of testis in the Albino rat model

AimsThis study was designed to evaluate the protective and therapeutic efficacy of platelet-rich plasma (PRP) against testicular degeneration and germ cell apoptosis after induced spermatic cord torsion/detorsion (TD) in rats. MaterialsForty rats were allocated into 5 groups: 1) control, 2) short torsion/detorsion (STD), 3) long torsion detorsion (LTD), 4) protective (PRP/P) and 5) treatment (PRP/T). Testicular ischemia was induced by twisting the right testis 1080° clockwise for 2.5 h. PRP (10 μl) was injected intra-testicular 5 min before (PRP/P) and 3 h after (PRP/T) detorsion. At the end of the experiment, rats were euthanized at 2, 30, 2, and 30 days for groups 2–5 respectively. Nitric oxide, malondialdehyde, catalase, total antioxidant capacity, reduced glutathione, glutathione-S-transferase, interleukin1 beta, tumor necrosis factor, caspase-3, and B-cell lymphoma 2 expressions were assessed in the testes. Moreover, histological examination was performed. Key findingsPRP treatment significantly mitigated the torsion-detorsion induced testicular degeneration. Particularly, by improving the state of oxidative stress (NO, P = 0.0001) and antioxidant markers (TAC, GSH, GST, P = 0.0001–0.01) and decreasing the expression of IL-1β, TNF-α and cas 3 and increase the BCL2 fold changes (P = 0.0001). The protective use of PRP is superior to the therapeutic use of PRP in the restoration of the testicular histoarchitecture following TD. SignificanceThis study illustrates the cyto-protective role of PRP against TD induced testicular cell injury that highlight possible application of PRP as a complementary therapy in different testicular degenerative diseases which might attribute to its ability to ameliorate the oxidative stress and inhibit induced apoptosis.

Loganin alleviates testicular damage and germ cell apoptosis induced by AGEs upon diabetes mellitus by suppressing the RAGE/p38MAPK/NF-κB pathway.

Diabetes mellitus (DM) damages male reproduction at multiple levels, such as endocrine secretion, spermatogenesis and penile erection. We herein investigated the protective effects and mechanism of loganin targeting the advanced glycation end products (AGEs)/receptor for AGEs (RAGE)/p38 mitogen‐activated protein kinase (p38MAPK)/NF‐κB signalling pathway. Loganin relieved the general DM symptoms and decreased the blood glucose level of KK‐Ay DM mice. Haematoxylin‐eosin staining demonstrated that loganin ameliorated testicular histology and function and enhanced the activities of testis‐specific markers lactate dehydrogenase (LDH), acid phosphatase (ACP) and gamma‐glutamyl transferase (γ‐GT). Loganin also showed evident anti‐oxidative stress, anti‐apoptotic and anti‐inflammatory effects on DM‐induced reproductive damage by restoring glutathione (GSH) level and superoxide dismutase (SOD) activity, as well as reducing reactive oxygen species (ROS) level and Bax/Bcl‐2 ratio in vivo and in vitro. Western blotting exhibited that loganin significantly inhibited the AGEs/RAGE/p38MAPK/NF‐κB signalling pathway. Acridine orange and ethidium bromide staining (AOEB) and Western blotting showed that loganin in combination with inhibitors of RAGE, p38MAPK and NF‐κB exerted stronger anti‐apoptotic effects on AGE‐induced GC‐2 cell damage compared with loganin alone. In conclusion, loganin can protect against DM‐induced reproductive damage, probably by suppressing the AGEs/RAGE/p38MAPK/NF‐κB pathway.

Insulin-like growth factors 1 and 2 are associated with testicular germ cell proliferation and apoptosis during fish reproduction.

To support sperm production, fish testes undergo intense tissue remodelling, with endocrine, paracrine and autocrine signals regulating gonad physiology. The aim of this study was to investigate the testicular expression of insulin-like growth factor (Igf) 1 and Igf2 during spermatogenesis, and their relationship with cell proliferation and apoptosis throughout the reproductive cycle. The study was performed in male Hypostomus garmani, a catfish living in headwater rivers of the São Francisco River basin, Brazil. Spermatogenesis was analysed using histology, morphometry, immunohistochemistry and terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nick end-labelling (TUNEL) analysis at different maturity stages. The results showed the proliferation of spermatogonia throughout the reproductive cycle, with a higher rate during the ripe stage. Germ and Sertoli cells expressed Igf1 at all stages of testicular maturity, Igf2 was predominant at the ripe stage and both Igf1 and Igf2 occurred at the spent stage. Caspase-3 and TUNEL analysis revealed a higher rate of apoptosis at the spent stage associated with reduced expression of Igf1 and Igf2. Sertoli cell proliferation was associated with spermatogonia and spermatocyte cysts at different stages of the reproductive cycle. Together, the data support a proliferative role for Igf1 and Igf2 in regulating testicular apoptosis in H. garmani, with cyclical variation in their expression during gonad maturation.