Aluminum exposure induces ferroptosis in spermatogenic cells of mice through iron overload and lipid peroxidation.

Identification of the gene for the developmentally expressed 70 kDa heat-shock protein (P70) of mouse spermatogenic cells

Di-2-ethylhexyl phthalate (DEHP) which belongs to phthalatic-acid esters, is a kind of harmful, global environmental pollutants. It is a known endocrine disrupting chemical and male reproductive toxicant. However, the mechanism by which DEHP exposure result in male reproductive toxicity is still unclear. To elucidate the productive toxicity mechanism of DEHP, we attemptted to investigate oxidative stress, apoptotic effects, mRNA and protein expression of apoptosis-associated genes including FasL, caspase-3, and caspase-8 in GC-2spd (mouse spermatogenic cells). The results showed that, with the increase of DEHP concentration, cell apoptosis rate increased; the activities of relation index of oxidative stress such as malondialdehyde (MDA), superoxide dismutase (SOD) and glutatione peroxidase (GSH-PX) changed significantly; the mRNA and protein expression levels of FasL, caspase-3, -8, altered obviously. These results suggested that DEHP could induce apoptosis of GC-2spd cells through oxidative stress and FasL-dependent pathway.

Introduction: The aim of this study was to investigate the effects of mangosteen extract on the number of spermatogenic cells in mice exposed to cigarette smoke. Objective: Thirty mice aged 8 to 12 weeks were randomly divided into 5 groups. The negative control group (K-) received 1% CMC Na/head, the positive control group (K+) was exposed to smoke and received 1% CMC Na/head, (P1) was exposed to smoke and administered mangosteen extract 6,045 mg/head, (P2) was exposed to smoke and administered mangosteen extract 12.09 mg/head, (P3) was exposed to smoke and administered mangosteen extract 24.18 mg/head. Each group was exposed to one cigarette per day, and treatments were administered one hour after smoke exposure. All treatments and smoke exposure lasted for about 45 days. Necropsy was performed after the final day of treatment, and histopathological slides of the testes were processed and stained under a light microscope. The observed parameter was spermatogenic cell count. The data were analyzed using analysis of variance (ANOVA) based on a completely randomized design, and further analyzed using Duncan’s multiple range. Results: Cigarette smoke significantly reduced spermatogenic cells (spermatogonia, primary spermatocytes, and spermatids) (p<0.05). Administration of mangosteen peel extract significantly increased spermatogenic cells (p<0.05). The highest increase in spermatogenic cells was observed in the group given 12.09 mg/gram BW of mangosteen peel extract (P2). The increase in spermatogenic cells due to the administration of mangosteen peel extract and cigarette smoke did not reach normal conditions (K-). Conclusion: This study concludes that mangosteen peel extract (Garcinia mangostana Linn) could maintain the number of spermatogenic cells in male mice (Mus musculus) exposed to cigarette smoke (p<0.005).

Y-box proteins bind DNA and RNA and are characterized by a cold shock domain and a carboxyl-terminus containing clusters of aromatic and basic residues that alternate with clusters of acidic residues. Y-box proteins 1 and 3 in mouse testis were cloned here by 3' rapid amplification of cDNA ends (RACE) using a degenerate primer. Northern blots and reverse transcription-polymerase chain reaction (RT-PCR) established that the levels of Y-box protein 1 and 3 mRNAs are regulated individually: (i) Y-box protein 1 mRNA is strongly expressed in kidney, whereas Y-box protein 3 mRNA is strongly expressed in heart and muscle; (ii) Y-box protein 1 and 3 mRNAs are weakly expressed in early prepubertal testis and strongly expressed in pachytene spermatocytes, round spermatids, and elongated spermatids; and (iii) prepubertal testes and meiotic and haploid spermatogenic cells express two alternatively spliced Y-box protein 3 mRNAs encoding isoforms with different carboxyl termini, whereas somatic tissues primarily express one form. Sucrose gradients reveal that approximately 27% of both Y-box protein 3 mRNAs are translationally active in adult testis. In conclusion, spermatogenic cells in mice express five isoforms of Y-box proteins including Y-box protein 1, and two isoforms each of Y-box proteins 2 and 3. This multiplicity is intriguing because Y-box proteins are thought to activate transcription and repress translation in spermatogenic cells.

Dynamic and Temporal Transcriptomic Analysis Reveals Ferroptosis-Mediated Antileukemia Activity of S-Dimethylarsino-Glutathione: Insights into Novel Therapeutic Strategy

The goals of this work were to create germ-cell-stage-specific cDNA libraries from mouse spermatogenic cells and to employ a novel two-step genetic screen to identify gene sequences present during the critical meiotic stage of spermatogenesis. Highly enriched germ-cell fractions were prepared from adult and juvenile mouse testes, and purity of these fractions was extensively analyzed by light and electron microscopy. Standard techniques were used to prepare cDNA libraries from populations of mixed leptotene and zygotene (L/Z) spermatocytes, pachytene (P) spermatocytes, and round spermatids. These libraries were analyzed with respect to representation of sequences from ubiquitously expressed genes, and from genes expressed at specific germ-cell stages as well as from genes expressed in testicular somatic cells. For the first step of the screening procedure, testicular cDNA was prepared from mutant mice carrying the T(X;11)38H chromosomal translocation that causes spermatogenic arrest at early meiotic prophase. This mixed cDNA probe was used to screen the libraries from L/Z and P spermatocytes to detect sequences failed to hybridize. The clones identified were characterized for ability to hybridize to various germ-cell-specific cDNAs to verify that they represented sequences present in normal spermatogenic meiotic cells. These clones were then subjected to a second screening with another mutant probe; this time the cDNA probe was from testes of sterile mice bearing the T(X;16)16H chromosomal translocation that causes spermatogenic arrest at late meiotic prophase. This screen identified 27 clones that were not represented in testicular cDNA from T38-bearing mice or from T16-bearing mice. These clones may represent sequences essential for normal completion of the genetic events of meiosis during spermatogenesis. Likewise, the secondary screen identified 19 clones that were not represented in testicular cDNA from T38-bearing mice but were represented in testicular cDNA of T16-bearing mice. These clones are thus gene sequences present in spermatogenic cells during the time from early meiotic prophase to mid-to-late prophase. This strategy represents the first use of genetic aberrations in differential screening to identify genes expressed at specific times during mammalian spermatogenesis.

An Integrase Facilitates Long-Lasting Foreign Gene Expression In Vivo in Mouse Spermatogenic Cells.

An integrase facilitates long-lasting foreign gene expression In Vivo in mouse spermatogenic cells

Simple SummaryZearalenone is a mycotoxin that can cause reproductive toxicity after long-term feeding in domestic animals and it affects spermatogenesis in male domestic animals. Ferroptosis is a newly identified type of programmed cell death, which depends on iron accumulation and lipid peroxidation. Fer-1 inhibits the process of ferroptosis. However, it is not clear whether ferroptosis plays a role in zearalenone (ZEA) damage to spermatogenesis. This study establishes a ZEA damage model of in male mice. After Fer-1 intervention, it was found that Fer-1 improves the antioxidant system of mice testis, reduces iron levels, restores related factors of Nrf2, SLC7A11, and GPX4 to normal levels, and accelerates reproductive injury recovery.Male reproductive health is critically worsening around the world. It has been reported that the mycotoxin ZEA causes reproductive toxicity to domestic animals and affects spermatogenesis, thereby inhibiting male reproductive function. Ferroptosis is a newly identified type of programmed cell death that is different from apoptosis and it depends on iron accumulation and lipid peroxidation. Whether ferroptosis is linked to ZEA’s detrimental effect on spermatogenesis needs to be further explored. This study clarifies ferroptosis’s involvement in ZEA-induced damage on spermatogenesis. The reproductive injury model used in this study was induced by gavaging male mice in the ZEA treatment group with 30 μg/kg of ZEA for five weeks. Results show that ZEA treatment reduced mouse sperm motility and concentration, destroyed the structure of the seminiferous tubules of the testis, damaged the antioxidant defense system, and blocked spermatogenesis. Ferrostatin-1 (Fer-1) inhibition of ferroptosis partially alleviated ZEA-induced oligozoospermia in mice. In addition, ZEA treatment was found to activate a signaling pathway associated with ferroptosis in mouse testis. ZEA also downregulated the expression of Nrf2, SLC7A11, and GPX4, and decreased the protein expression of SLC7A11 and GPX4, resulting in the accumulation of lipid peroxides and an increase in the level of 4-HNE protein in the testis. Importantly, these changes were accompanied by an increase in the relative contents of Fe2+ and Fe3+. Iron accumulation and lipid peroxidation are the causes of ferroptosis in spermatogenic cells, leading to a decrease in sperm motility and concentration. While the administration of Fer-1 at 0.5 and 1 mg/kg also increased the expression of SLC7A11 and GPX4 proteins by upregulating Nrf2 expression, reducing iron accumulation, and reversing ZEA-induced ferroptosis, Fer-1 at 1.5 mg/kg had the best repairing effect for all parameters. In conclusion, ZEA-induced ferroptosis may be mediated by a notable reduction in Nrf2, SLC7A11 and GPX4 expression levels. Overall, ferroptosis is a novel therapeutic target for mitigating ZEA-induced reproductive toxicity.

Molecular cloning of novel temperature-induced expressed sequence tags related to apoptosis in spermatogenic cells of mouse

Cistanche total glycoside capsule promotes sperm maturation and fertility by activating the NELL2 Lumicrine pathway in a male reproductive impairment model.

Asthma occurs accompanied by the ferroptosis in bronchial epithelial cells, during which Interleukin-6 (IL-6) plays a key role. However, the associations between IL-6, ferroptosis and asthma have not been reported. Bronchial epithelial cells BEAS-2B cells were induced by different concentrations of IL-6 and cell viability was detected by MTT assay. The TBARS production rate was detected by corresponding kit. The expression of oxidative stress-related indexes was detected by ELISA. The Iron Assay Kits detected total iron levels and ferrous ion (Fe2+) levels. Labile iron pool assay was used to detect the cell unstable iron pool. The expression of ferroptosis-related proteins was detected by Western blot. To further examine the mechanism of action, ferroptosis inhibitor Ferrostatin 1 (Fer-1), antioxidant NAC, and the iron supplement Fe were added. We found that IL-6 decreased the activity, promoted lipid peroxidation, disrupted iron homeostasis of BEAS-2B cells, and induced iron death in bronchial epithelial BEAS-2B cells. However, pretreatment with Ferrostatin-1 (Fer-1) and antioxidant NAC partially reversed the effect of IL-6 on lipid peroxidation and ferroptosis in BEAS-2B cells, while Fe augmented the effect. Overall, IL-6 promotes ferroptosis in bronchial epithelial cells by inducing reactive oxygen species (ROS)-dependent lipid peroxidation and disrupting iron homeostasis.

SummaryTranscriptional coactivator with PDZ‐binding motif (TAZ) directly interacts with transcription factors and regulates their transcriptional activity. Extensive functional studies have shown that TAZ plays critical regulatory roles in stem cell proliferation, differentiation, and survival and also modulates the development of organs such as the lung, kidney, heart, and bone. Despite the importance of TAZ in stem cell maintenance, TAZ function has not yet been evaluated in spermatogenic stem cells of the male reproductive system. Here, we investigated the expression and functions of TAZ in mouse testis. TAZ was expressed in spermatogenic stem cells; however, its deficiency caused significant structural abnormalities, including atrophied tubules, widened interstitial space, and abnormal Leydig cell expansion, thereby resulting in lowered sperm counts and impaired fertility. Furthermore, TAZ deficiency increased the level of apoptosis and senescence in spermatogenic cells and Leydig cells upon aging. The expression of senescence‐associated β‐galactosidase (SA‐βgal), secretory phenotypes, and cyclin‐dependent kinase inhibitors (p16, p19, and p21) significantly increased in the absence of TAZ. TAZ downregulation in testicular cells further increased SA‐βgal and p21 expression induced by oxidative stress, whereas TAZ overexpression decreased p21 induction and prevented senescence. Mechanistic studies showed that TAZ suppressed DNA‐binding activity of p53 through a direct interaction and thus attenuated p53‐induced p21 gene transcription. Our results suggested that TAZ may suppress apoptosis and premature senescence in spermatogenic cells by inhibiting the p53‐p21 signaling pathway, thus playing important roles in the maintenance and control of reproductive function.

The incidence of depression among humans is growing worldwide, and so is the use of antidepressants. However, our fundamental understanding regarding the mechanisms by which these drugs function and their off-target effects against human sexuality remains poorly defined. The present study aimed to determine their differential toxicity on mouse spermatogenic cells and provide mechanistic data of cell-specific response to antidepressant and neuroleptic drug treatment. To directly test reprotoxicity, the spermatogenic cells (GC-1 spg and GC-2 spd cells) were incubated for 48 and 96 h with amitriptyline (hydrochloride) (AMI), escitalopram (ESC), fluoxetine (hydrochloride) (FLU), imipramine (hydrochloride) (IMI), mirtazapine (MIR), olanzapine (OLZ), reboxetine (mesylate) (REB), and venlafaxine (hydrochloride) (VEN), and several cellular and biochemical features were assessed. Obtained results reveal that all investigated substances showed considerable reprotoxic potency leading to micronuclei formation, which, in turn, resulted in upregulation of telomeric binding factor (TRF1/TRF2) protein expression. The TRF-based response was strictly dependent on p53/p21 signaling and was followed by irreversible G2/M cell cycle arrest and finally initiation of apoptotic cell death. In conclusion, our findings suggest that antidepressants promote a telomere-focused DNA damage response in germ cell lines, which broadens the established view of antidepressants’ and neuroleptic drugs’ toxicity and points to the need for further research in this topic with the use of in vivo models and human samples.

In a process called capacitation, mammalian sperm gain the ability to fertilize after residing in the female tract. During capacitation the mouse sperm plasma membrane potential (E(m)) hyperpolarizes. However, the mechanisms that regulate sperm E(m) are not well understood. Here we show that sperm hyperpolarize when external Na(+) is replaced by N-methyl-glucamine. Readdition of external Na(+) restores a more depolarized E(m) by a process that is inhibited by amiloride or by its more potent derivative 5-(N-ethyl-N-isopropyl)-amiloride hydrochloride. These findings indicate that under resting conditions an electrogenic Na(+) transporter, possibly involving an amiloride sensitive Na(+) channel, may contribute to the sperm resting E(m). Consistent with this proposal, patch clamp recordings from spermatogenic cells reveal an amiloride-sensitive inward Na(+) current whose characteristics match those of the epithelial Na(+) channel (ENaC) family of epithelial Na(+) channels. Indeed, ENaC-alpha and -delta mRNAs were detected by reverse transcription-PCR in extracts of isolated elongated spermatids, and ENaC-alpha and -delta proteins were found on immunoblots of sperm membrane preparations. Immunostaining indicated localization of ENaC-alpha to the flagellar midpiece and of ENaC-delta to the acrosome. Incubations known to produce capacitation in vitro or induction of capacitation by cell-permeant cAMP analogs decreased the depolarizing response to the addition of external Na(+). These results suggest that increases in cAMP content occurring during capacitation may inhibit ENaCs to produce a required hyperpolarization of the sperm membrane.