Positive PCNA and Ki-67 Expression in the Testis Correlates with Spermatogenesis Dysfunction in Fluoride-Treated Rats

Age-dependent changes in the expression and localization of LYZL4, LYZL6 and PCNA during testicular development in the Ashidan yak

Lysozyme like 4 (LYZL4), lysozyme like 6 (LYZL6) and proliferating cell nuclear antigen (PCNA) are implicated in the regulation of testicular function, but there was no research reported available on the expression patterns of LYZL4, LYZL6 and PCNA genes at different developmental stages of yak testes. In this study, we used the qRT-PCR, western blotting and immunohistochemistry estimated the LYZL4, LYZL6 and PCNA gene expression and protein lo-calization at different developmental stages of yak testes. The qPCR results showed that the mRNA expression of LYZL4, LYZL6 and PCNA genes significantly increased with age in the testes of yaks. Western blot results showed that the protein abundance of LYZL4, LYZL6 and PCNA in yak testes was significantly higher after puberty than before puberty. Furthermore, the results of immunohistochemistry indicated that LYZL4, LYZL6 and PCNA may be involved in the regulation of spermatogonia proliferation and Leydig cell function in immature testis. In adult yak testes, LYZL4, LYZL6 and PCNA may involve in the development of round spermatids and primary spermatocytes during testicular development. Our results indicated that LYZL4, LYZL6 and PCNA may be involved in the development of Sertoli cells, Leydig cells and gonocytes in yak testes.

Dissecting the dynamic cellular transcriptional atlas of adult teleost testis development throughout the annual reproductive cycle

Teleost testis development during the annual cycle involves dramatic changes in cellular compositions and molecular events. In this study, the testicular cells derived from adult black rockfish at distinct stages - regressed, regenerating and differentiating - were meticulously dissected via single-cell transcriptome sequencing. A continuous developmental trajectory of spermatogenic cells, from spermatogonia to spermatids, was delineated, elucidating the molecular events involved in spermatogenesis. Subsequently, the dynamic regulation of gene expression associated with spermatogonia proliferation and differentiation was observed across spermatogonia subgroups and developmental stages. A bioenergetic transition from glycolysis to mitochondrial respiration of spermatogonia during the annual developmental cycle was demonstrated, and a deeper level of heterogeneity and molecular characteristics was revealed by re-clustering analysis. Additionally, the developmental trajectory of Sertoli cells was delineated, alongside the divergence of Leydig cells and macrophages. Moreover, the interaction network between testicular micro-environment somatic cells and spermatogenic cells was established. Overall, our study provides detailed information on both germ and somatic cells within teleost testes during the annual reproductive cycle, which lays the foundation for spermatogenesis regulation and germplasm preservation of endangered species.

Fluoride exposure during puberty induces testicular impairment via ER stress-triggered apoptosis in mice

Fluoride, a ubiquitous environmental compound, carries significant health risks at excessive levels. This study investigated the reproductive toxicity of fluoride exposure during puberty in mice, focusing on its impact on testicular development, spermatogenesis, and underlying mechanisms. The results showed that fluoride exposure during puberty impaired testicular structure, induced germ cell apoptosis, and reduced sperm counts in mice. Additionally, the SOD activity and GSH content were significantly decreased, while MDA content was significantly elevated in the NaF group. Immunohistochemistry showed an increase in the number of cells positive for GRP78, a key ER stress marker. Moreover, qRT-PCR and Western blot analyses confirmed the upregulation of both Grp78 mRNA and protein expression, as well as increased mRNA expression of other ER stress-associated genes (Grp94, chop, Atf6, Atf4, and Xbp1) and enhanced protein expression of phosphorylated PERK, IRE1α, eIF2α, JNK, XBP-1, ATF-6α, ATF-4, and CHOP. In conclusion, our findings demonstrate that fluoride exposure during puberty impairs testicular structure, induces germ cell apoptosis, and reduces sperm counts in mice. ER stress may participate in testicular cell apoptosis, and contribute to the testicular damage and decreased sperm counts induced by fluoride.

Insulin-like growth factor-1 promotes the testicular sperm production by improving germ cell survival and proliferation in high-fat diet-treated male mice

BACKGROUND

A decrease in semen volume among men is comparable to the rising prevalence of obesity worldwide. The anabolic hormone insulin-like growth factor-1 (IGF-1) can promote proliferation and differentiation in cultured mouse spermatogonial stem cells and alleviate abnormal in vitro spermatogenesis. Additionally, serum IGF-1 level is negatively correlated with body mass index. Whereas the role of IGF-1 in the sperm production in obese men remains unclear.

OBJECTIVE

To investigate the therapeutic effect and potential mechanism of IGF-1 on spermatogenesis of high-fat diet (HFD)-induced obesity mice.

METHODS

An HFD-induced obesity mouse model was established. Alterations in testicular morphology, sperm count, proliferation, and apoptosis were observed by H&E staining,immunohistochemistry, immunofluorescence, and Western blotting. Exogenous recombinant IGF-1 was administered to obese mice to investigate the correlations between altered testicular IGF-1 levels and sperm production.

RESULTS

The sperm count was reduced, the testicular structure was disordered, and sex hormone levels were abnormal in HFD-fed mice compared with normal diet-fed mice. The expression of proliferation-related antigens such as proliferating cell nuclear antigen (PCNA) and Ki-67 was decreased, while that of proapoptotic proteins such as c-caspase3 was increased in testes from HFD-fed mice. Most importantly, the phosphorylation of insulin-like growth factor-1 receptor (IGF-1R) in testes was decreased due to reductions in IGF-1 from hepatocytes and Sertoli cells. Recombinant IGF-1 alleviated these functional impairments by promoting IGF-1R, Akt, and Erk1/2 phosphorylation in the testes.

CONCLUSIONS

Insufficient IGF-1/IGF-1R signaling is intimately linked to damaged sperm production in obese male mice. Exogenous IGF-1 can improve survival and proliferation as well as sperm production. This study provides a novel theoretical basis and a target for the treatment of obese men with oligozoospermia.

Unveiling the therapeutic potential of thymol from Nigella sativa L. seed: selective anticancer action against human breast cancer cells (MCF-7) through down-regulation of Cyclin D1 and proliferative cell nuclear antigen (PCNA) expressions

BACKGROUND

Breast adenocarcinoma cells (MCF-7) are characterized by the overexpression of apoptotic marker genes and proliferative cell nuclear antigen (PCNA), which promote cancer cell proliferation. Thymol, derived from Nigella sativa (NS), has been investigated for its potential anti-proliferative and anticancer properties, especially its ability to suppress Cyclin D1 and PCNA expression, which are crucial in the proliferation of cancer cells.

METHODS

The cytotoxicity of thymol on MCF-7 cells was assessed using 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) and lactate dehydrogenase (LDH) release methods. Thymol was tested at increasing concentrations (0-1000 µM) to evaluate its impact on MCF-7 cell growth. Additionally, Cyclin D1 and PCNA gene expression in thymol-treated and vehicle control groups of MCF-7 were quantified using real-time Polymerase Chain Reaction (RT-qPCR). Protein-ligand interactions were also investigated using the CB-Dock2 server.

RESULTS

Thymol significantly inhibited MCF-7 cell growth, with a 50% inhibition observed at 200 µM. The gene expression of Cyclin D1 and PCNA was down-regulated in the thymol-treated group relative to the vehicle control. The experimental results were verified through protein-ligand interaction investigations.

CONCLUSIONS

Thymol, extracted from NS, demonstrated specific cytotoxic effects on MCF-7 cells by suppressing the expression of Cyclin D1 and PCNA, suggesting its potential as an effective drug for MCF-7. However, additional in vivo research is required to ascertain its efficacy and safety in medical applications.

Potential role of inducible nitric oxide synthase (iNOS) activity in testicular dysfunction following co-administration of alcohol and combination antiretroviral therapy (cART) in diabetic rats: an immunohistochemistry study

Diabetes, alcohol abuse, and combination antiretroviral therapy (cART) use have been reported to cause multi-organ complications via induction of oxidative stress and inflammation. Moreover, these are the most common factors implicated in male reproductive dysfunctions. This study evaluated testicular oxidative stress, inflammation, apoptosis, and germ cell proliferation in diabetic rats receiving alcohol or cART and their combination. Thirty adult male Sprague Dawley rats were divided into five groups, each consisting of six rats; control, diabetic only (DM), diabetic treated with alcohol (DM + A), diabetic treated with cART (DM + cART), and diabetic treated with both alcohol and cART (DM + A + cART). After 90 days of treatment, the rats were terminated, and the testes were extracted and processed for immunohistochemistry analysis for oxidative stress, inflammatory cytokines, apoptosis, and cell proliferation marker. In comparison to the control, oxidative stress markers, inducible nitric oxide synthase (iNOS), malondialdehyde (MDA), and 8-hydroxydeoxyguanosine (8-OHDG) increased significantly in all treated groups. Expression of testicular proinflammatory cytokines, interleukin-1β, and tumor necrosis factor-α was upregulated in all treated groups, but interleukin-6 was upregulated in DM, DM + cART, and DM + A + cART treated groups and was downregulated in the DM + A treated group. All treated animal groups showed an upregulation of apoptotic marker (caspase 3) and a downregulation of proliferation marker (Ki-67). However, Ki-67 staining intensity significantly increased in treated animals compared to the control. These findings suggest that diabetes, alcohol abuse, cART use, and their combination via iNOS activity upregulation can induce inflammation and oxidative stress in testicular tissue, stimulating germ cell apoptosis and proliferation inhibition leading to failure of spermatogenesis.

Novel insights into the synergistic effects of selenium nanoparticles and metformin treatment of letrozole - induced polycystic ovarian syndrome: targeting PI3K/Akt signalling pathway, redox status and mitochondrial dysfunction in ovarian tissue

PURPOSE

Polycystic ovary syndrome (PCOS) has a series of reproductive and metabolic consequences. Although the link between PCOS, IR, and obesity, their impact on the pathogenesis of PCOS has yet to be determined. Dysfunction of PI3K/AKT pathway has been reported as the main cause of IR in PCOS. This study purposed to explore the effects of selenium nanoparticles (SeNPs) alone and combined with metformin (MET) in a PCOS-IR rat model.

METHODS

After 3 weeks of treatment with SeNPs and/or MET, biochemical analysis of glycemic & lipid profiles, and serum reproductive hormones was performed. Inflammatory, oxidative stress, and mitochondrial dysfunction markers were determined colormetrically. The expression of PI3K and Akt genes were evaluated by Real-time PCR. Histopathological examination and Immunohistochemical analysis of Ki-67 expression were performed.

RESULTS

The results showed that treatment with SeNPs and/or MET significantly attenuated insulin sensitivity, lipid profile, sex hormones levels, inflammatory, oxidative stress and mitochondrial functions markers. Additionally, PI3K and Akt genes expression were significantly upregulated with improved ovarian histopathological changes.

CONCLUSION

Combined SeNPs and MET therapy could be potential therapeutic agent for PCOS-IR model via modulation of the PI3K/Akt pathway, enhancing anti-inflammatory and anti-oxidant properties and altered mitochondrial functions.

HighlightsThe strong relationship between obesity, insulin resistance, and polycystic ovarian syndrome.Disturbance of the PI3K/Akt signaling pathway is involved in the progression of polycystic ovary syndrome-insulin resistance (PCOS-IR).In PCOS-IR rats, combined SeNPs and metformin therapy considerably alleviated IR by acting on the PI3K/Akt signaling pathway.The combination of SeNPs and metformin clearly repaired ovarian polycystic pathogenesis and improved hormonal imbalance in PCOS-IR rats.

Insights from the maternal lineage of the F2 generation after exposure to an environmentally relevant dose of benzo(a)pyrene in the male rats of F0 generation

Benzo(a)pyrene (BaP) is a substance with the potential to induce endocrine disruption in the F0 generation and cause adverse multigenerational effects (F1 generation) for reproductive parameters in rats. The objective of this study was to investigate the occurrence of transgenerational inheritance in the reproductive aspects of male and female rats belonging to the F2 generation (MF2). This investigation was conducted following the exposure of male rats from the F0 generation to BaP to assess potential effects on subsequent generation from the maternal lineage (F1). For that, juvenile male Wistar rats (F0) were orally exposed to BaP (0.1 µg/kg/day) for 31 consecutive days. In adulthood, they were mated with untreated females to obtain female offspring (F1), which later produced the MF2. In the MF2 generation, both males and females exhibited increased body weight on postnatal day (PND) 1. In MF2 males, we observed delayed preputial separation, altered pup weight, reduced levels of follicle-stimulating hormone (FSH), increased intratesticular testosterone levels, decreased type A sperm, epididymal disturbances, reduced 5 α-reductase activity, increased testicular proliferation, and alterations in testicular antioxidant enzymes. In MF2 females, we noted morphological uterine enlargement, reduced sexual activity, and decreased progesterone levels. The findings suggest that the alterations observed in both MF2 males and females can be attributed to modifications in the sperm from F0 generation, which were subsequently transmitted to F1 females and MF2 generation due to BaP exposure.

The impact of busulfan on the testicular structure in prepubertal rats: A histological, ultrastructural and immunohistochemical study

Busulfan is a widely used cancer chemotherapeutic agent. Temporary or permanent sterility in male patients is one of the most common side effects of this drug. The present study was performed to evaluate the changes in the microscopic structure of the testes of prepubertal rats, as well as the changes in PCNA and caspase-3 immune expression, at different durations after busulfan administration. The rats were 5 weeks old and were divided into two main groups. Control group and busulfan treated group. Busulfan treated group received a single dose of busulfan (40 mg/kg), then animals were subdivided to three subgroups; IIa, IIb, IIc which were sacrificed after four, ten and twenty weeks, respectively, from the beginning of the experiment. Light and electron microscopic studies were done. Serum testosterone level and relative testes weight were assessed. Immunohistochemical staining for anti-proliferating cell nuclear antigen (PCNA) and anti-caspase-3 antigen was also done. Morphometric and statistical studies were carried out. Group II revealed histological and ultrastructural degenerative changes including congested blood vessels and degenerated spermatogenic epithelium, Sertoli cells, and Leydig cells. These changes were more evident after 10 weeks of busulfan administration and were accompanied by absence of mature sperms in the lumen of seminiferous tubules. These changes were associated with a significant reduction in relative testes weight, testosterone level, germinal epithelial height and seminiferous tubule diameter. Moreover, PCNA and caspase-3 immune expression was significantly altered in busulfan treated group. Mild improvement in testicular structure was observed 20 weeks after busulfan treatment.

Study of spermatogenic and Sertoli cells in the Hu sheep testes at different developmental stages

Spermatogenesis is a highly organized process by which undifferentiated spermatogonia self-renew and differentiate into spermatocytes and spermatids. The entire developmental process from spermatogonia to sperm occurs within the seminiferous tubules. Spermatogenesis is supported by the close interaction of germ cells with Sertoli cells. In this study, testicular tissues were collected from Hu sheep at 8 timepoints after birth: 0, 30, 90, 180, 270, 360, 540, and 720 days. Immunofluorescence staining and histological analysis were used to explore the development of male germ cells and Sertoli cells in the Hu sheep testes at these timepoints. The changes in seminiferous tubule diameter and male germ cells in the Hu sheep testes at these different developmental stages were analyzed. Then, specific molecular markers were used to study the proliferation and differentiation of spermatogonia, the timepoint of spermatocyte appearance, and the maturation and proliferation of Sertoli cells in the seminiferous tubules. Finally, the formation of the blood-testes barrier was studied using antibodies against the main components of the blood-testes barrier, β-catenin, and ZO-1. These findings not only increased the understanding of the development of the Hu sheep testes, but also laid a solid theoretical foundation for Hu sheep breeding.

Protective effect of Mucuna pruriens (L.) DC. var. pruriens seed extract on apoptotic germ cells in ethanolic male rats

Thai Mucuna pruriens (L.) DC. var pruriens (T-MP) seed containing levodopa (L-DOPA) and antioxidant capacity has been shown to improve sexual behavior and male reproductive parameters in rats treated with ethanol (Eth). However, its protective effect on testicular apoptotic germ cells has never been reported. This study aimed to investigate the potential effects of T-MP seed extract on expressions of caspase, proliferating cell nuclear antigen (PCNA), and dopamine D2 receptor (D2R) proteins in Eth rats. Thirty-six male Wistar rats were divided into four groups (9 animals/group), including control, Eth, T-MP150+Eth, and T-MP300+Eth, respectively. Control rats received distilled water, and Eth rats received Eth (3g/kg BW; 40%v/v). The T-MP groups were treated with T-MP seed extract at a dose of 150 or 300 mg/kg before Eth administration for 56 consecutive days. The results showed that the seminiferous tubule diameter and epithelial height were significantly increased in both T-MP treated groups compared to the Eth group. Additionally, the caspase-9 and -3, and PCNA expressions were decreased, but D2R expression was markedly increased in T-MP groups. It was concluded that T-MP seed extract could protect testicular apoptosis induced by Eth via changes in caspase, PCNA, and D2R protein expressions.

Modulatory role of Coriandrum sativum (coriander) extract against diabetic complications on the gonads of female rats and their offspring

It is well known that diabetes is associated with impairment of ovarian and testicular structure and function. Coriander (Coriandrum sativum L.) is identified as one of the oldest herbal plants valued for its nutritional and medicinal properties. This work is mainly designed to evaluate the possible modulatory role of dry coriander fruit extract against gonadal impairments associated with diabetes in female rats and their pups. Twenty-four pregnant rats were divided into four groups (n = 6): group I served as control, group II was administered daily with coriander fruit extract (250 mg/kg b.wt), group III was injected interaperitoneally with a single dose of streptozotocin (STZ) (80 mg/kg b.wt), and group IV was injected with single dose of STZ and post administered coriander extract. The experiment was conducted from the 4th day of gestation till the end of weaning. At the end of the experiment, the mothers' rats and their offspring were weighed, sacrificed, the ovaries from mothers as well as ovaries and testes from offspring were immediately excised, and processed for histological, immunohistochemical and evaluation of apoptosis and transforming growth factorβ (TGF-β). Also, blood samples were collected and analyzed to estimate the levels of sex hormones as well as antioxidants.In STZ induced diabetes in mother's rats and their offspring, the ovarian sections revealed severe histopathological signs included several atretic follicles, dilated and congested blood capillaries. Additionally, the testicular sections of offspring appeared with destructive seminiferous tubules. Immunohistochemically, the ovarian sections displayed weak to negative expression for calretinin marker however the testicular sections showed strong expression for Bax protein (apoptotic marker) and weak to negative expression for Ki67 protein (proliferative marker). Also, the mean % values of positively expressed cells for TGF-β and annexin-v markers (late and early apoptosis indicator) were significantly elevated in the ovarian and testicular tissues of STZ-induced group of mother's rats and their pups if compared with control. Further results revealed that the levels of insulin, FSH, LH, estrogen, SOD and CAT were significantly decreased if compared with control however the levels of MDA and NO were significantly elevated. Administration of coriander fruit extract to diabetic rats successfully alleviated most of the altered histological, immunohistochemical, biochemical, and apoptotic changes induced by diabetes. Coriandrum sativum fruit extract has a powerful ameliorative role against STZ-induced diabetic gonadal dysfunctions in female rats and their offspring.

Necessity to Pay Attention to the Effects of Low Fluoride on Human Health: an Overview of Skeletal and Non-skeletal Damages in Epidemiologic Investigations and Laboratory Studies

Due to the implementation of water improvement and fluoride reduction plans supported by central and local governments in recent years, areas with high fluoride exposure are being gradually decreased. Therefore, it is of practical importance to study the effect of low fluoride on human health. Epidemiologic investigations and in vivo and in vitro studies based on low fluoride have also confirmed that fluoride not only causes skeletal damage, such as dental fluorosis, but also causes non-skeletal damage involving the cardiovascular system, nervous system, hepatic and renal function, reproductive system, thyroid function, blood glucose homeostasis, and the immune system. This article summarizes the effects of low fluoride on human and animal skeletal and non-skeletal systems. A preliminary exploration of corresponding mechanisms that will help to fully understand the harm of low fluoride on human health was undertaken to provide the basis for establishing new water fluoride standards and help to implement individual guidance.

Fluoride-Induced Sperm Damage and HuR-Mediated Excessive Apoptosis and Autophagy in Spermatocytes

It is critical to determine the mechanism underlying fluoride (F)-induced damage of the testes to develop appropriate strategies for monitoring and intervention. In the present study, exposure to 50 mg/L sodium fluoride (NaF) for 90 days damaged the normal structure of the testes and quality of the sperm, particularly the spermatocytes, and triggered overexpression of human antigen R (Elavl1/HuR) according to western blotting and immunofluorescence. Furthermore, 0.5 mM NaF exposure for 24 h exposure increased the proportion of apoptosis and expression of caspase-3 and caspase-9 in mouse spermatocytes (GC-2spd cell line), whereas inhibition of HuR reduced apoptosis and the expression of caspase-3 and caspase-9. Additionally, inhibition of HuR alleviated F-induced autophagy based on observation of the autophagy bodies, detection of autophagy activity, and analysis of the expression of the LC3II/LC3I and p62 proteins. These results reveal that excessive F can lead to overexpression of HuR, resulting in high levels of apoptosis and autophagy in spermatocytes. These findings improve the understanding of the mechanisms underlying F-induced male reproductive toxicity, and HuR may be explored as a treatment target for certain conditions. Excessive fluoride can induce overexpression of HuR in testis and result in excessive apoptosis and autophagy in spermatocytes as well as male reproductive damage, such as a decreased sperm count, decreased sperm motility, and increased deformity rate.

Disordered Expression of Tight Junction Proteins Is Involved in the Mo-induced Intestinal Microenvironment Dysbiosis in Sheep

To evaluate the molybdenum (Mo)-induced changes of intestinal morphology and the relationship of intestinal tight junction (TJ) proteins expression and intestinal barrier function, a total of 20 healthy sheep were randomly divided into five groups of four: 0, 5, 10, 20, and 50 mg/kg BW/day Na₂MoO₄·2H₂O were administrated in five groups named control group, Mo 5 group, Mo 10 group, Mo 20 group, and Mo 50 group, respectively. After 28 days of Mo treatment, the duodenum, the jejunum, and the ileum tissue were collected. The histopathology and the developmental parameters were evaluated by hematoxylin-eosin staining. The intestinal epithelial cell DNA damage was detected by TdT-mediated dUTP nick end labeling assay. The intestinal glycoprotein and the goblet cells were analyzed by Alcian Blue-Periodic Acid-Schiff (AB-PAS) staining and PAS staining, respectively. TJ proteins were determined by immunofluorescence technology. Results showed that excessive Mo significantly decreased the small intestinal villus height (VH), crypt depth (CD), VH/CD, and mucosal thickness (P < 0.05 or P < 0.01) while induced the damage of DNA in small intestinal epithelial cells. Moreover, excessive Mo injured intestinal barrier function by decreasing the percent of glycoprotein distribution area (P < 0.05) and the relative density of intestinal goblet cells (P < 0.05). Mo treatment induced decreased (P < 0.01) expression of Zonula Occludens-1, Occludin, and Claudin-1. In conclusion, excessive Mo interfered with the expression of TJ proteins, inhibited intestinal epithelial development, and further aggravated the intestinal barrier function damage, leading to disturbing the small intestinal microenvironment balance.

Alleviating effects of selenium on fluoride-induced testosterone synthesis disorder and reproduction toxicity in rats

Fluoride (F) exists widely in food, water and other natural resources, and can cause damage to the reproductive system of human and animals. Studies have shown that selenium (Se) is a necessary trace element to maintain the normal male reproductive system. However, it is not clear whether it can alleviate the damage of reproductive system induced by F. Hence, sodium fluoride (NaF) was administered singly in drinking water at 100 mg L^-1 alone and co-administered by drinking with sodium selenite (Na₂SeO₃) at 0.5, 1.0, 2.0 mg L^-1 for 10 consecutive weeks. The results demonstrated that the sperm deformity rate were increased significantly by F, however, it was improved significantly after the addition of 2.0 mg L^-1 Na₂SeO₃. The contents of glutathione peroxidase 4 (GPX-4), selenoprotein P (SePP), pregnenolone (PREG), androstenedione (ASD), and testosterone (T) were reduced obviously in the F group, however, it was increased significantly after adding 0.5, 1.0 and 2.0 mg L^-1 Na₂SeO₃. F decreased noticeably the mRNA and protein expression levels of steroidogenic acute regulatory protein (StAR), cytochrome P450 cholesterol side chain lyase (P450scc), 3β-hydroxysteroid dehydrogenase (3β-HSD), cytochrome P450 17α-hydroxylase (P450c17) and 17β-hydroxysteroid dehydrogenase (17β-HSD), which was increased obviously after the addition of 1.0 and 2.0 mg L^-1 Na₂SeO₃. In summary, 2.0 mg L^-1 Na₂SeO₃ can alleviate testosterone synthesis disorder induced by F via reducing oxidative stress, increasing the level of selenoprotein in testis and regulating the content of related hormones and enzyme activity during testosterone synthesis pathway.

The possible protective and therapeutic effects of ginger and cinnamon on the testis and coda epididymis of streptozotocin-induced-diabetic rats: Histological and biochemical studies

Diabetes mellitus (DM) is a metabolic condition characterized by high blood sugar levels with serious system complications. Ginger (Zingiber officinale) and Cinnamon (Cinnamomum zeylanicum) have anti-diabetic activities. The goal of this study is to evaluate the possible protective and therapeutic effects of ginger and Cinnamon against histological, Ki67 Immunohistochemistry (IHC) and biochemical studies in testis and coda epididymis of Streptozotocin (STZ) induced diabetic rats. The experimental rats were divided into six groups: G1 was the control, G2 induced diabetic without treatment, G3 was treated with ginger before induction of DM (ginger protective), G4 were given ginger after DM induction (ginger therapeutic), G5 were given cinnamon before induction of DM (cinnamon protective) and G6 were given cinnamon after DM induction (cinnamon therapeutic). In diabetic rats' significant increases in fasting blood sugar and body weight were observed after three weeks. Ginger and cinnamon effectively decreased serum glucose levels. Histopathological evaluations of seminiferous tubules and coda epididymis sections from diabetic rats showed severe damage to them. Furthermore, the sections of seminiferous tubules and coda epididymis rats administered ginger and cinnamon extract showed normal structure, healthy lining epithelium and sperm contents compared to diabetic rats. The results of the study show that both Ginger and Cinnamon aqueous extracts are effective as both hypoglycemic natural supplements that can protect against diabetic-induced testicular damage as well as share in the reservation of the cauda epididymal structure and sperm contents.

Loss of WNT4 in the gubernaculum causes unilateral cryptorchidism and fertility defects

Undescended testis (UDT) affects 6% of male births. Despite surgical correction, some men with unilateral UDT may experience infertility with the contralateral descended testis (CDT) showing no A-dark spermatogonia. To improve our understanding of the etiology of infertility in UDT, we generated a novel murine model of left unilateral UDT. Gubernaculum-specific Wnt4 knockout (KO) mice (Wnt4-cKO) were generated using retinoic acid receptor β2-cre mice and were found to have a smaller left-unilateral UDT. Wnt4-cKO mice with abdominal UDT had an increase in serum follicle-stimulating hormone and luteinizing hormone and an absence of germ cells in the undescended testicle. Wnt4-cKO mice with inguinal UDT had normal hormonal profiles, and 50% of these mice had no sperm in the left epididymis. Wnt4-cKO mice had fertility defects and produced 52% fewer litters and 78% fewer pups than control mice. Wnt4-cKO testes demonstrated increased expression of estrogen receptor α and SOX9, upregulation of female gonadal genes, and a decrease in male gonadal genes in both CDT and UDT. Several WNT4 variants were identified in boys with UDT. The presence of UDT and fertility defects in Wnt4-cKO mice highlights the crucial role of WNT4 in testicular development.

Reproductive development of male rats exposed in utero to stress and/or sertraline

Despite increased prescription of sertraline during pregnancy, little is known about its action on reproductive development. Therefore, the present study aimed to investigate the impact that stress, associated or not with sertraline, causes on the reproductive development of male rats. Pregnant Wistar rats were divided into 4 groups (n = 16/group): CO - received filtered water; SE - received 20 mg/kg sertraline; ST - submitted to restraint stress and received filtered water; SS - submitted to restraint stress and received sertraline. The treatment was carried out from gestational days (GD) 13 to 20. The animals were euthanized on GD 20 (n = 8/group), postnatal day (PND) 45 (n = 8/group) and PND 110 (n = 8/group). The testes and epididymis were analyzed histologically, and immunohistochemistry was performed on the testes by proliferating cell nuclear antigen (PCNA) and the Wilms tumor protein (Wt1). Sperm quality was also analyzed on PND 110. The evolution of body weight, anogenital distance (AGD), and puberty installation day were also verified. Statistical analysis: Two-way ANOVA or Kruskal-Wallis test (p ≤ 0.05). Fetal testes presented a large number of acidophilic cells in the sertraline-exposed groups. The SS group also showed a decrease in the nuclear volume of Leydig cells. This same group showed low expression of PCNA and Wt1, decreased weight of the testes and epididymis, lower AGD, and delayed puberty installation. The adulthood groups exposed to sertraline presented alterations in sperm morphology and motility. The results demonstrated that prenatal exposure to sertraline compromises the development of the rat reproductive system.

BPA disrupted the testis testosterone levels by interfering ER enrichments within StAR 5' flanking region in rare minnow Gobiocypris rarus

Bisphenol A (BPA) is a widely used endocrine disruptor, which has attracted much attention due to its harmful effects on male reproduction. To investigate the interference of BPA on steroid synthesis in males, male rare minnows (Gobiocypris rarus) were exposed to 15 μg L^-1 BPA for 7, 14 and 21 d. Meanwhile, a positive control group was performed with 25 ng L^-1 17α-ethynyl estradiol (EE2). Results showed that BPA exposure induced lower testosterone (T) levels, while affecting the transcripts of steroidogenic gene StAR. Moreover, BPA induced abnormal germ cells proliferation in the testis in rare minnow. Transcriptome analysis showed that 354 transcripts significantly differentially expressed after BPA exposure for 14 d, several of them were enriched in the signaling pathways of cell cycle process, PPAR signaling pathway, the steroid synthesis pathway and estrogen signaling pathway. BPA significantly increased estrogen receptor (ER) levels and induced abnormal protein levels of PPARγ. BPA disrupted the StAR expression by interfering ER enrichments within StAR 5' flanking region. Additionally, our study also revealed that BPA and EE2 might have different mechanisms for interfering with steroid hormone levels and germ cells proliferation in the testis.

Effect of Fluoride on Cytotoxicity Involved in Mitochondrial Dysfunction: A Review of Mechanism

Fluoride is commonly found in the soil and water environment and may act as chronic poison. A large amount of fluoride deposition causes serious harm to the ecological environment and human health. Mitochondrial dysfunction is a shared feature of fluorosis, and numerous studies reported this phenomenon in different model systems. More and more evidence shows that the functions of mitochondria play an extremely influential role in the organs and tissues after fluorosis. Fluoride invades into cells and mainly damages mitochondria, resulting in decreased activity of mitochondrial related enzymes, weakening of protein expression, damage of respiratory chain, excessive fission, disturbance of fusion, disorder of calcium regulation, resulting in the decrease of intracellular ATP and the accumulation of Reactive oxygen species. At the same time, the decrease of mitochondrial membrane potential leads to the release of Cyt c, causing a series of caspase cascade reactions and resulting in apoptosis. This article mainly reviews the mechanism of cytotoxicity related to mitochondrial dysfunction after fluorosis. A series of mitochondrial dysfunction caused by fluorosis, such as mitochondrial dynamics, mitochondrial Reactive oxygen species, mitochondrial fission, mitochondrial respiratory chain, mitochondrial autophagy apoptosis, mitochondrial fusion disturbance, mitochondrial calcium regulation are emphasized, and the mechanism of the effect of fluoride on cytotoxicity related to mitochondrial dysfunction are further explored.

Targeting p-AKT/mTOR/MAP kinase signaling, NLRP3 inflammasome and apoptosis by fluvastatin with or without taxifolin mitigates gonadal dysfunction induced by bisphenol-A in male rats

Bisphenol-A (BPA) is a chemical substance that is widely used in industry for manufacturing of plastic bottles and resins. Recent reports found that BPA may mimic the effects of estrogen to a great manner that might disrupt the normal hormonal balance in the human body. Fluvastatin is an agent used for treatment of hypercholesterolemia that was proven to possess promising antioxidant ant anti-inflammatory properties. Taxifolin is a polyphenolic compound with potential antioxidant and antiestrogenic effects. The present study investigated the prospect of fluvastatin with or without taxifolin to mitigate testicular dysfunction elicited by BPA in rats. In a model of BPA-induced testicular toxicity, the hormonal profile was assessed and the testicular tissues were examined by biochemical analysis, histopathology, and immunohistochemistry. Fluvastatin with or without taxifolin improved the body weight gain, hormonal profile, testicular weight and functions, sperm characteristics, the antioxidant status, and the anti-inflammatory mechanisms together with enhancement of autophagy and suppression of the proapoptotic events induced by BPA in the testicular tissues. In addition, fluvastatin with or without taxifolin significantly mitigated the histopathological and the immunohistochemical changes induced by BPA in the testicular tissues. These desirable effects were more pronounced with fluvastatin/taxifolin combination relative to the use of each of these agents alone. In tandem, fluvastatin/taxifolin combination might counteract the pathogenic events induced by BPA in the testicular tissues which may be considered as a novel strategy for amelioration of these disorders.

In vivo and in vitro protective effects of the Wuzi Yanzong pill against experimental spermatogenesis disorder by promoting germ cell proliferation and suppressing apoptosis

ETHNOPHARMACOLOGICAL RELEVANCE

Wuzi Yanzong pill (WZYZP) is a classical traditional Chinese medicine (TCM) formula originated from the Tang dynasty. WZYZP has a long history of use for reinforcing kidney and alleviating male infertility in China.

AIM OF THE STUDY

The effect of WZYZP on male infertility and the mechanism underlying this effect was not clarified clearly. Therefore, this study aimed to investigate the protective effect of WZYZP in experimental spermatogenesis disorder via in vivo and in vitro studies, to promote the use of this formula for the treatment of spermatogenesis disorder.

MATERIAL AND METHODS

Male SD rats were exposed to tripterygium glycosides to induce experimental spermatogenesis disorder, and WZYZP was subsequently administrated at different dosages for treatment. Sperm counts, sperm motility, and serum hormone levels were detected. HE staining and TUNEL staining were performed to evaluate the pathological lesions and apoptosis of testes, respectively. Next, germ cells were isolated from spermatogenesis disorder-model rats and treated with WZYZP- containing serum at different concentrations. CCK-8 assay and flow cytometry assay were performed to detect cell proliferation and apoptosis. Immunofluorescence assay, qRT-PCR and Western blotting analyses were performed to detect the expression of Beclin 1, LC3 and TGF-β-PI3k/AKT-mTOR pathway - related factors, including TGF-β, PI3K, AKT, mTOR, 4 EBP-1 and p70S6K.

RESULTS

In vivo experiments showed that WZYZP protected against spermatogenesis disorder in model rats by improving sperm count and motility, as well as restoring serum hormone levels. HE and TUNEL staining demonstrated that the pathological injuries and cell apoptosis in testes of the model rats were alleviated by WZYZP treatment. Moreover, in vitro experiments of germ cells isolated from spermatogenesis disorder-model rats showed that WZYZP treatment increased the cell proliferation, inhibited cell apoptosis and autophagy. qRT-PCR and Western blotting assay results showed that this protective effect was associated with the regulation of the TGF-β/PI3K/AKT/mTOR signaling pathway. The expression levels of p-PI3K/PI3K, p-AKT/AKT, p-mTOR/mTOR, 4 EBP-1 and p70S6K were increased, while TGF-β was inhibited in the WZYZP treated groups.

CONCLUSION

The results showed that WZYZP could protect against experimental spermatogenesis disorder by increasing the germ cell proliferation and inhibiting their apoptosis. Our support the clinical use of this formula for the management of spermatogenesis disorder.

Thymol alleviates imidacloprid-induced testicular toxicity by modulating oxidative stress and expression of steroidogenesis and apoptosis-related genes in adult male rats

The present work was designed to assess the potential ameliorative effect of thymol on the testicular toxicity caused by imidacloprid (IMI) in adult male rats. Forty adult male rats were allocated into four groups; control group was given corn oil, thymol-treated group (30 mg/kg b.wt), IMI-treated group (22.5 mg/kg b.wt), and IMI + thymol-treated group. All administrations were done by gavage every day for duration of 56 days. As a result, the IMI exposure caused a significant decline in the body weight change, reproductive organ weights, sperm functional parameters, and serum level of testosterone, widespread histological alterations, and apoptosis in the testis. Additionally, the IMI-treated rats exhibited a remarkable increment in the serum levels of follicle stimulating hormone and luteinizing hormone. Also, IMI induced testicular oxidative stress, as indicated by elevated malondialdehyde (MDA) levels and a marked decline in the activity of antioxidant enzymes and reduced glutathione (GSH), and total antioxidant capacity (TAC) levels. Moreover, IMI treatment significantly downregulated the mRNA expression of steroidogenic genes and proliferating cell nuclear antigen (PCNA) immunoexpression in the testicular tissue. However, thymol co-administration significantly mitigated the IMI-induced toxic effects. Our findings suggested that IMI acts as a male reproductive toxicant in rats and thymol could be a potential therapeutic option for IMI reprotoxic impacts.

Vitamin B12 suppresses GADD153, prevents apoptosis and regulates the testicular function in methotrexate treated rat testis

Methotrexate (MTX) is an anti-neoplastic drug that also causes testicular damage. Vitamin B12 (Vit B12) is a water soluble vitamin that is required for normal metabolism. We investigated Vit B12 as a possible protective agent against testicular damage caused by MTX treatment. We divided rats into four groups: control group, Vit B12 group treated with Vit B12 daily for 15 days, MTX group treated with MTX on day 8, MTX + Vit B12 group treated with MTX on day 8 + Vit B12 for 15 days. Serum levels of follicle stimulating hormone (FSH), luteinizing hormone (LH) and testosterone were measured. We also measured proliferating cell nuclear antigen (PCNA), connexin43 (Cx43) and the growth arrest- and DNA damage-inducible gene, 153 (GADD153), using immunohistochemical staining. Apoptosis was assessed using TUNEL staining. The MTX group exhibited degeneration of seminiferous tubules; decreased serum testosterone, LH and FSH levels; fewer PCNA positive cells; increased Cx43 expression; and increased GADD153 and TUNEL stained cells compared to the control group. These pathologic findings were substantially reversed In the MTX + Vit B12 group. MTX caused increased endoplasmic reticulum stress and apoptosis via GADD153. Consequently, Vit B12 potentially is a protective agent against damage caused by MTX.

Low protein diet and methyl-donor supplements modify testicular physiology in mice

The link between male diet and sperm quality has received significant investigation. However, the impact diet and dietary supplements have on the testicular environment has been examined to a lesser extent. Here, we establish the impact of a sub-optimal low protein diet (LPD) on testicular morphology, apoptosis and serum fatty acid profiles. Furthermore, we define whether supplementing a LPD with specific methyl donors abrogates any detrimental effects of the LPD. Male C57BL6 mice were fed either a control normal protein diet (NPD; 18% protein; n = 8), an isocaloric LPD (LPD; 9% protein; n = 8) or an LPD supplemented with methyl donors (MD-LPD; choline chloride, betaine, methionine, folic acid, vitamin B12; n = 8) for a minimum of 7 weeks. Analysis of male serum fatty acid profiles by gas chromatography revealed elevated levels of saturated fatty acids and lower levels of mono- and polyunsaturated fatty acids in MD-LPD males when compared to NPD and/or LPD males. Testes of LPD males displayed larger seminiferous tubule cross section area when compared to NPD and MD-LPD males, while MD-LPD tubules displayed a larger luminal area. Furthermore, TUNNEL staining revealed LPD males possessed a reduced number of tubules positive for apoptosis, while gene expression analysis showed MD-LPD testes displayed decreased expression of the pro-apoptotic genes Bax, Csap1 and Fas when compared to NPD males. Finally, testes from MD-LPD males displayed a reduced telomere length but increased telomerase activity. These data reveal the significance of sub-optimal nutrition for paternal metabolic and reproductive physiology.

The Therapeutic Potential of Amniotic Fluid-Derived Stem Cells on Busulfan-Induced Azoospermia in Adult Rats

BACKGROUND

Busulfan is an alkylating chemotherapeutic agent that is routinely prescribed for leukemic patients to induce myelo-ablation. However, it also results in azoospermia and infertility in cancer survivors. This research was constructed to explore the possible therapeutic role of amniotic fluid-derived stem cells (AFSCs) in improving busulfan-induced azoospermia in adult rats.

METHODS

Forty two adult male albino rats were randomized into: (1) control group, (2) azoospermia group, (3) spontaneous recovery group, and (4) AFSCs-treated group, in which AFSCs were transplanted through their injection into the testicular efferent ducts. The assessment included a histo-pathological examination of the seminiferous tubules by the light and transmission electron microscopes. Additionally, the confocal laser scanning microscope was used for confirmation of homing of the implanted cells. Moreover, we conducted an immuno-fluorescence study for detection of the proliferating cell nuclear antigen (PCNA) in the spermatogenic cells, epididymal sperm count, and a histo-morphometric study.

RESULTS

AFSCs successfully homed over the basement membrane of the injured seminiferous tubules. They greatly attenuated busulfan-induced degenerative and oxidative changes. They also caused a re-expression of PCNA in the germ cells, leading to resumption of spermatogenesis and re-appearance of spermatozoa.

CONCLUSION

AFSCs could be a promising treatment modality for male infertility induced by chemotherapy, as they possess prominent regenerative, anti-apoptotic, and anti-inflammatory potentials.

Wuzi Yanzong Pill-Based on Network Pharmacology and In Vivo Evidence-Protects Against Spermatogenesis Disorder via the Regulation of the Apoptosis Pathway

The crisis of male infertility is an issue of human reproductive health worldwide. The Wuzi Yanzong pill (WZYZP) is a traditional Chinese medicine prescription that shows efficacy in kidney reinforcement and essence benefit to ameliorate male reproductive dysfunctions. However, the pharmacological mechanisms of the WZYZP on male infertility have not been investigated and clarified clearly. This study was designed to investigate the effects of the WZYZP on spermatogenesis disorder and explore its underlying pharmacological mechanisms. First, based on a network pharmacology study, 39 bioactive compounds and 40 targets of the WZYZP associated with spermatogenesis disorder were obtained, forming a tight compound-target network. Molecular docking tests showed tight docking of these compounds with predicted targeted proteins. The protein-protein interaction (PPI) network identified TP53, TNF, AKT1, Bcl-XL, Bcl-2, and IκBA as hub targets. The Kyoto Encyclopedia of Genes and Genomes pathway network and pathway-target-compound network revealed that the apoptosis pathway was enriched by multiple signaling pathways and multiple targets, including the hub targets. Subsequently, the chemical characterization of WZYZP was analyzed using liquid chromatography to quadrupole/time-of-flight mass spectrometry, and 40 compounds in positive ion mode and 41 compounds in negative ion mode in the WZYZP were identified. Furthermore, based on the prediction of a network pharmacology study, a rat model of spermatogenesis disorder was established to evaluate the curative role and underlying mechanisms of the WZYZP. The results showed that WZYZP treatment improved rat sperm quality and attenuated serum hormone levels, reversed histopathological damage of the testis, reduced cell apoptosis in testis tissues, and ameliorated the expression of the predicted hub targets (TP53, TNF-α, AKT1, NFκB, and IκBA) and the apoptosis related proteins (Bcl-XL, Bcl-2, Bax, Caspase 3, and Caspase 9). These results indicated that the WZYZP has a protective effect on spermatogenesis disorder, suggesting that it could be an alternative choice for male infertility therapy.

Characterization of sheep spermatogenesis through single-cell RNA sequencing

Spermatogenesis is an important biological process in male reproduction. The interaction between male germ cells and somatic cells during spermatogenesis, is necessary for male reproductive activities. This cellular heterogeneity has made it difficult to profile distinct cell types at different stages of development. Here, we present the first comprehensive, unbiased single-cell transcriptomic study of sheep spermatogenesis using 10× genomics single cell sequencing (scRNA-seq). We collected scRNA-seq data from 11 772 cells from the adult sheep testis and identified all known germ cells (including early primary spermatocytes, late primary spermatocytes, round spermatids, elongated spermatids, and sperm), and somatic cells (Sertoli cells and Leydig cells), as well as one somatic cell that unexpectedly contained leukocytes. The functional enrichment analysis indicated that several pathways of cell cycle, gamete generation, protein processing, and mRNA surveillance pathways were significantly enriched in testicular germ cell types, and ribosome pathway was significantly enriched in testicular somatic cell types. Further analysis identified several stage-specific marker genes of sheep germ cells, such as EZH2, SOX18, SCP2, PCNA, and PRKCD. Our research explored for the first time of the changes in the transcription level of various cell types during the process of sheep spermatogenesis, providing new insights for sheep spermatogenesis and spermatogenic cell development.

A Comparative Analysis of Fluoride-Contaminated Groundwater and Sodium Fluoride-Induced Reproductive Toxicity and Its Reversibility in Male Rats

The present study was undertaken to investigate the toxic effect of sodium fluoride (NaF)- and fluoride (F)-contaminated groundwater on male reproduction and it's reversibility in male rats. Adult male rats were orally treated with different concentrations of NaF- (1 mg, 5 mg, and 10 mg/kg/bw/rat) and F-contaminated groundwater for 52 days and after the confirmation of F-induced damage, the rats were allowed for recovery studies for 52 days. Exposure of NaF- and F-contaminated groundwater caused significant decline in total sperm count, sperm motility, serum concentration of testosterone, activities of testicular 3β-HSDH, counts of type A spermatogonia, preleptotene spermatocytes, midpachytene spermatocytes, elongated spermatids and round spermatids, activities of testicular and spermatozoa SOD and CAT, and increase in sperm abnormality and concentration of MDA of testis and spermatozoa compared to controls. Further, significant histological alterations characterized by shrunken seminiferous tubules and degeneration of different stages of spermatogonial cells were observed in rats treated with NaF of 10 mg/kg/bw and F-contaminated groundwater Majority of parameter studied showed severe damage in 10 mg/kg/bw of NaF-treated rats compared to that of F-contaminated groundwater. Further, dose-dependent alterations were observed with increase in concentration of NaF in most of the parameters. In recovery group rats of NaF- and F-contaminated groundwater, all the parameters were restored to control levels. The present study revealed the toxic effect of NaF and F-contaminated groundwater on male reproductive system of rats and the effects induced by NaF were dose-dependent. In addition, the study clearly revealed that F-induced toxicity on male reproduction is reversible in short-term exposure.

Perinatal exposure to Bisphenol A disturbs the early differentiation of male germ cells

Understanding the effects of Bisphenol A (BPA) on early germ cell differentiation and their consequences in adult life is an area of growing interest in the field of endocrine disruption. Herein, we investigate whether perinatal exposure to BPA affects the differentiation of male germ cells in early life using a transgenic mouse expressing the GFP reporter protein under the Oct4 promoter. In this model, the expression of GFP reflects the expression of the Oct4 gene. This pluripotency gene is required to maintain the spermatogonial stem cells in an undifferentiated stage. Thus, GFP expression was used as a parameter to evaluate the effect of BPA on early germ cell development. Female pregnant transgenic mice were exposed to BPA by oral gavage, from embryonic day 5.5 to postnatal day 7 (PND7). The effects of BPA on male germ cell differentiation were evaluated at PND7, while sperm quality, testicular morphology, and protein expression of androgen receptor and proliferating cell nuclear antigen were studied at PND130. We found that perinatal/lactational exposure to BPA up-regulates the expression of Oct4-driven GFP in testicular cells at PND7. This finding suggests a higher proportion of undifferentiated spermatogonia in BPA-treated animals compared with non-exposed mice. Moreover, in adulthood, the number of spermatozoa per epididymis was reduced in those animals perinatally exposed to BPA. This work shows that developmental exposure to BPA disturbed the normal differentiation of male germ cells early in life, mainly by altering the expression of Oct4 and exerted long-lasting sequelae at the adult stage, affecting sperm count and testis.

Short term chronic toxicity of tributyltin on the testes of adult albino rats and the possible protective role of omega-3

The declining rate of male fertility is a growing concern. Tributyltin (TBT) is a well-known endocrine disruptor (ED), that induces imposex in female gastropods and is widely used in various industrial applications. The aim of this study was to evaluate the toxic effects of TBT on the testes of adult albino rats and the possible role of omega-3. Forty two adult male albino rats were divided into five groups; control group (Group I) and four experimental groups: omega-3 treated group, TBT treated group, TBT & omega-3 treated group and follow up group. At the end of the study, the rats were subjected to biochemical, histological, immunohistochemical staining for Ki-67 and seminal examinations. Our results clarfied that TBT induced a significant decrease in testosterone, FSH, LH and serum glutathione peroxidase levels and a significant increase in the serum Malondialdehyde as compared to the control group. Tributyltin induced disorganization and shrinkage of seminiferous tubules, apoptosis, cellular damage and marked reduction in the germinal epithelium. A significant decrease in the cell proliferation and arrested spermatogenesis were also detected. Seminal analysis of TBT group showed a significant affection of all parameters as compared to other groups. Omega-3 ameliorated all of these hazardous effects. Follow up group still showed toxic effects. In conclusion, TBT has a toxic effect on the testis. Increased testicular oxidative stress, cellular damage and arrest of spermatogenesis with attenuation in antioxidant defenses are all contributing factors. Omega-3 can protect against TBT induced reproductive toxicity.

Fluoride induced mitochondrial impairment and PINK1-mediated mitophagy in Leydig cells of mice: In vivo and in vitro studies

It is very important to explore the potential harm and underlying mechanism of fluoride due to the extensive distribution and the significant health risks of fluoride in environment. The objective of this study to investigate whether fluoride can induce mitochondrial impairment and mitophagy in testicular cells. For this, 40 male mice were randomly divided into four groups treated with 0, 0.6, 1.2, 2.4 mM NaF deionized water, respectively, for 90 days continuously. The results showed that mitophagy was triggered by F in testicular tissues, especially in the Leydig cells by transmission electron microscopy and mitophagy receptor PHB2 locations by immunofluorescence. Furthermore, TM3 Leydig cells line was employed and treated with 0, 0.125, 0.25, and 0.5 mM NaF for 24 h. The mitochondrial function indicators and mitophagy maker PHB2, COX IV and regulator PINK1 in transcript and protein levels in Leydig cells were examined by the methods of qRT-PCR, western blotting, and immunofluorescence co-localization. The results showed that fluoride decreased the mitochondrial membrane potential with a concomitant increase in the number of lysosomes. Meanwhile, fluoride exposure also increased the expressions of PINK1 and PHB2 in TM3 Leydig cells. These results revealed that fluoride could induce mitochondrial impairment and excessive PINK1/Parkin-mediated mitophagy in testicular cells, especially in Leydig cells, which could contribute to the elucidation of the mechanisms of F-induced male reproductive toxicity.

Morin ameliorates the testicular apoptosis, oxidative stress, and impact on blood-testis barrier induced by photo-extracellularly synthesized silver nanoparticles

Silver nanoparticles (AgNPs) have been widely produced for different industrial purposes. Recently, biogenic synthesis of AgNPs has emerged although the extent of effects from exposure, oral exposure in particular, to nanomaterials synthesized in such a manner remains elusive. The main objective of this study was to evaluate the effects of oral administration of a dose of 50 mg/Kg body weight AgNPs biosynthesized in baker's yeast (Saccharomyces cerevisiae) over a period of eight weeks on the reproductive performance and the possibility of a protective effect through co-administration of morin. Forty-eight male Sprague-Dawley rats were used in four experimental groups (control, morin-treated group, AgNP-treated, and AgNP + morin co-treatment). AgNPs produced no significant alteration in daily food intake or body weight. Both the absolute and relative testicular weights were significantly reduced but not the epididymal weight. Also, serum levels of urea, creatinine, uric acid, and liver enzymes were significantly elevated. Furthermore, AgNPs significantly downregulated the hypothalamic-pituitary-gonadal axis. This corresponds to lower motility and viability percent, reduced sperm concentration, and a higher abnormality ratio as well as a prominent alteration in the blood-testis barrier (BTB) and testicular histology and induction of testicular apoptosis and oxidative stress. The supplementation of morin evidently restored most of the reproductive characters to its physiological range. We can conclude that exposure to the biologically synthesized AgNPs for an extended period of time has proven to be a health risk that can be ameliorated via oral administration of some bioactive agents including morin.

Fluoride exposure arrests the acrosome formation during spermatogenesis via down-regulated Zpbp1, Spaca1 and Dpy19l2 expression in rat testes

The exposure and health effects of fluoride are an ongoing topic that has attracted worldwide attention. Fluoride exposure disturbs the testicular development, sexual hormone levels and spermatogenesis. However, as to whether fluoride interferes with acrosome formation which is essential for production of capable spermatozoa during spermatogenesis still remains unclear. The objective was to determine the effects of fluoride on the acrosome formation and to further elucidate the potential mechanism of impaired reproductive function. For this, forty adult rats were assigned into four groups. The control group received distilled water, while the other three groups were treated with 25, 50 and 100 mg NaF/L via drinking water for 56 d, respectively. Testes were processed for total RNA extraction and western blot analysis. Three samples of each group were fixed in 2.5% glutaraldehyde solution for transmission electron microscopy analysis. From the results, we first found that fluoride decreased the expression of mRNA and protein levels of Zpbp1, Spaca1 and Dpy19l2 of seven markers during acrosome biogenesis in testes. Furthermore, fluoride damaged not only the acrosome structure, but also the structure of the nuclear lamina which was observed to be discontinuous and partially missing by transmission electron microscopy. Moreover, the results indicated that the altered structure in nuclear lamina maybe due to reduced LMNB2 expression in testis induced by fluoride. In a nutshell, fluoride exposure could restrain acrosome biogenesis during spermatogenesis and contribute to the elucidation of the underlying mechanisms of fluoride-induced male reproductive toxicity.

Effect of Fluoride on Small Intestine Morphology and Serum Cytokine Contents in Rats

This study aimed to determine the effect of excessive fluoride (F) on the morphological characteristics of the small intestine and the contents of serum cytokines in rats. A total of 48 3-week-old healthy female Sprague-Dawley rats were randomly divided into four groups (n = 12). The control group was given deionized distilled water, while the F treatment groups were treated with water containing 25, 50, and 100 mg F^-/L. After 70 days of treatment, the duodenum, the jejunum, and the ileum were collected to measure the developmental parameters and the distribution of intestinal glycoproteins, goblet cells, and mast cells through Pannoramic Viewer, Periodic Acid-Schiff (PAS) staining, Alcian blue and periodic acid-Schiff (AB-PAS) staining, and toluidine blue staining, respectively. The contents of cytokines, namely, interleukin (IL)-1β, IL-2, IL-6, and tumor necrosis factor (TNF)-α, in serum were detected via enzyme-linked immunosorbent assay (ELISA). Results showed that the villus height, crypt depth, villus height to crypt depth ratio, goblet cells, glycoproteins, and mast cells of the small intestine significantly decreased (P < 0.05 or P < 0.01) in the F treatment group. The contents of IL-1β, IL-2, IL-6, and TNF-α were significantly lower in the F treatment group than in the control group (P < 0.05 or P < 0.01). In summary, excessive F intake impaired intestinal development and immune function by decreasing the developmental parameters and the distribution of immune cells, glycoproteins, and cytokines.

Effects of Fluoride on Autophagy in Mouse Sertoli Cells

Fluoride had been reported to damage the structure and function of testicular tissues and reproductive cells; however, the mechanisms underlying its toxicity remained unclear. Autophagy plays a key role in reproductive function. In this study, we aimed to investigate the effect of fluoride on autophagy in Sertoli cells. Sertoli cells were exposed to 0, 0.125, 0.25, and 0.5 mM NaF for 24 h. The results showed that fluoride exposure up-regulated Beclin1 and p62 mRNA and protein expression levels with concomitant down-regulated mRNA and protein expression levels of LC3 and Atg5. In conclusion, exposure to fluoride impaired the autophagy process in Sertoli cells, which could be one of fluoride's mechanisms in male reproductive toxicity.

Mitochondrial respiratory chain complex abnormal expressions and fusion disorder are involved in fluoride-induced mitochondrial dysfunction in ovarian granulosa cells

Excessive fluoride intake has a strong female reproductive toxicity, which can result in follicular developmental dysplasia and decrease oocytes developmental potential. The underlying mechanisms of fluoride-induced mitochondrial dysfunction in ovarian granulosa cells remain largely unknown. In this study, the ultrastructure changes of mitochondria and DNA damage in ovarian granulosa cells were observed under transmission electron microscope and TUNEL staining. Then, the ATP content and ROS level in granulosa cells were measured. The expression of mitochondrial fusion proteins and mitochondrial respiratory chain complexes, including OPA1 and Mfn1, and NDUFV2, SDHA and CYC1, in the ovarian tissues were measured by immunohistochemistry, Western blot and Quantitative real-time PCR analyses. The expression of ATP5j and ATP5h in the ovarian tissues was also measured. Results show that fluoride treatment considerably damages mitochondrial ultrastructure and enhances the apoptosis of granulosa cells. The ATP content greatly decreased, whereas the ROS level increased after fluoride treatment. The expression level of Mfn1 in the ovarian tissue was up-regulated, whereas OPA1 expression had no significant change. The expression levels of NDUFV2, SDHA and CYC1 were considerably up-regulated, and the expression of ATP5j and ATP5h were down-regulated after fluoride treatment. In summary, the damage in the mitochondrial ultrastructure, ATP content decrease, ROS level increase and the abnormal expression of OPA1, Mfn1, NDUFV2, SDHA, CYC1, ATP5j and ATP5h in ovary tissue are closely associated with fluoride-induced mitochondrial dysfunction, which might be responsible for the follicular developmental dysplasia and the potential decrease in oocyte development induced by fluoride in female mice.

Fluoride altered rat's blood testis barrier by affecting the F-actin via IL-1α

Fluoride is known to affect the pro-inflammatory cytokines in the testis. Most of the recent literatures cited that cytokines regulate the blood-testis-barrier (BTB). However, the involvement of cytokines in the fluoride induced toxicity in BTB remains unclear. In order to study this, 60 male Sprague-Dawley (SD) rats were taken and randomly divided into 5 groups which included four fluoride groups exposed to 0, 25, 50, and 100 mg/L NaF in distilled water and one positive control group. On the 29th day of fluoride exposure, the positive control group rats were administered 0.1% CaCl₂ solution. Biotin tracer technology and transmission electron microscopy (TEM) analysis were applied to evaluate the function and ultra-structure of BTB. The expression levels of the BTB associated proteins, actin relative protein 3 (Arp3), interleukin-1 alpha (IL-1α), and transforming growth factor beta-3 (TGF-β3) were determined using Western blotting and Enzyme Linked Immunosorbent Assay (ELISA) respectively, meanwhile the actin filament (F-actin) was detected by fluorescent phalloidin conjugates. Our results revealed that the function and the ultra-structure of BTB in all the fluoride treated groups were damaged with a concomitant significant decreases in basal ectoplasmic specialization (basal ES), associated protein β-catenin, and F-actin. Moreover, Arp3 levels were significantly increased in 50 and 100 mg/L NaF groups. Meanwhile, IL-1α significantly increased in all the fluoride treated groups. In summary, we concluded that an increase in IL-1α induced by NaF significantly decreased the expression of F-actin and the organization of F-actin highly branched, which might facilitate the BTB's functional and ultra-structural variations.