Male Germ Cells Research Articles

Stanniocalcin-1 promotes temozolomide resistance of glioblastoma through regulation of MGMT

Temozolomide (TMZ) resistance is a major challenge in the treatment of glioblastoma (GBM). Tumour reproductive cells (TRCs) have been implicated in the development of chemotherapy resistance. By culturing DBTRG cells in three-dimensional soft fibrin gels to enrich GBM TRCs and performing RNA-seq analysis, the expression of stanniocalcin-1 (STC), a gene encoding a secreted glycoprotein, was found to be upregulated in TRCs. Meanwhile, the viability of TMZ-treated TRC cells was significantly higher than that of TMZ-treated 2D cells. Analysis of clinical data from CGGA (Chinese Glioma Genome Atlas) database showed that high expression of STC1 was closely associated with poor prognosis, glioma grade and resistance to TMZ treatment, suggesting that STC1 may be involved in TMZ drug resistance. The expression of STC1 in tissues and cells was examined, as well as the effect of STC1 on GBM cell proliferation and TMZ-induced DNA damage. The results showed that overexpression of STC1 promoted and knockdown of STC1 inhibited TMZ-induced DNA damage. These results were validated in an intracranial tumour model. These data revealed that STC1 exerts regulatory functions on MGMT expression in GBM, and provides a rationale for targeting STC1 to overcome TMZ resistance.

Fance deficiency impaired DNA damage repair of prospermatogonia and altered the repair dynamics of spermatocytes

BackgroundNon-obstructive azoospermia (NOA) is the most severe form of male infertility and affects approximately 1% of men worldwide. Fanconi anemia (FA) genes were known for their essential role in DNA repair and growing evidence showed the crucial role of FA pathway in NOA. However, the underlying mechanisms for Fance deficiency lead to a serious deficit and delayed maturation of male germ cells remain unclear.MethodsWe used Fance deficiency mouse model for experiments, and collected testes or epididymides from mice at 8 weeks (8W), 17.5 days post coitum (dpc), and postnatal 11 (P11) to P23. The mice referred to three genotypes: wildtype (Fance+/+), heterozygous (Fance+/-), and homozygous (Fance−/−). Hematoxylin and eosin staining, immunofluorescence staining, and surface spread of spermatocytes were performed to explore the mechanisms for NOA of Fance−/− mice. Each experiment was conducted with a minimum of three biological replicates and Kruskal-Wallis with Dunn’s correction was used for statistical analysis.ResultsIn the present study, we found that the adult male Fance−/− mice exhibited massive germ cell loss in seminiferous tubules and dramatically decreased sperms in epididymides. During the embryonic period, the number of Fance−/− prospermatogonia decreased significantly, without impacts on the proliferation (Ki-67, PCNA) and apoptosis (cleaved PARP, cleaved Caspase 3) status. The DNA double-strand breaks (γH2AX) increased at the cellular level of Fance−/− prospermatogonia, potentially associated with the increased nonhomologous end joining (53BP1) and decreased homologous recombination (RAD51) activity. Besides, Fance deficiency impeded the progression of meiotic prophase I of spermatocytes. The mechanisms entailed the reduced recruitment of the DNA end resection protein RPA2 at leptotene and recombinases RAD51 and DMC1 at zygotene. It also involved impaired removal of RPA2 at zygotene and FANCD2 foci at pachytene. And the accelerated initial formation of crossover at early pachytene, which is indicated by MLH1.ConclusionsFance deficiency caused massive male germ cell loss involved in the imbalance of DNA damage repair in prospermatogonia and altered dynamics of proteins in homologous recombination, DNA end resection, and crossover, providing new insights into the etiology and molecular basis of NOA.

The Role of Selected Elements in Oxidative Stress Protection: Key to Healthy Fertility and Reproduction.

Oxidative stress and its relationship to fertility and reproduction is a topic of interest in medicine, especially in the context of the effects of trace elements and micronutrients. Oxidative stress occurs when there is an excess of free radicals in the body, which can lead to cell and tissue damage. Free radicals are reactive oxygen species (ROS) that can be formed as a result of normal metabolic processes, as well as under the influence of external factors such as environmental pollution, UV radiation, and diet. Oxidative stress has a significant impact on fertility. In men, it can lead to DNA damage in sperm, which can result in reduced semen quality, reduced sperm motility and increased numbers of defective sperm, and free radical damage to sperm cell membranes causing a reduction in the number of available sperm. In women, oxidative stress can affect the quality of female reproductive cells, which can lead to problems with their maturation and with embryo implantation in the uterus and can also affect ovarian function and disrupt hormonal regulation of the menstrual cycle. A proper balance of trace elements and micronutrients is key to protecting against oxidative stress and maintaining reproductive health. Supplementation with appropriate elements such as zinc, selenium, copper, manganese, chromium, and iron can help reduce oxidative stress and improve fertility. This work discusses the effects of selected elements on oxidative stress parameters specifically in terms of fertility and reproduction.

Analysis of the morphology of Sus scrofa domesticus oocyte-cumulus complexes exposed to low and ultra-low temperatures

Relevance. The priority task of reproductive technologies in animal husbandry is the development of effective storage protocols for female gametes. One way to preserve gametes is vitrification, which reduces damage to intracellular organelles by increasing viscosity upon cooling and minimizing crystallization.Methods. Various additives to cryoprotectants are used for optimization. In our work, titanium tetrapolyethylene glycolate was used in a 10-fold molar excess of polyethylene glycol (TTPEG*10PEG), the nature of the effect of which on cells was studied during short-term storage at low (5 °С) and ultra-low temperatures (-196 °С).The purpose of the study is a comprehensive analysis of the morphology of gametes and somatic cells (cumulus) of ovarian follicles of pigs after exposure to low and ultra-low temperatures (vitrification) when included in the TTPEG*10PEG low-temperature storage and vitrification protocol.Results. Exposure to TTPEG*10PEG at 5 °С caused an increase in the level of oocytes with subsequent morphological degenerations in points with control (from 13% to 5%, р = 0.005). After vitrification with TTPEG*10PEG: the level of gametes with low cumulus cells expansion increased to 35% in terms of the proportion of control gametes (23%); the proportion of denudated gametes was reduced to 50% compared to the control 65% (р < 0.05); the level of morphologically degenerated gametes corresponded to that of native oocytes (8% each) and was lower than in the control (17%), р < 0.005. The obtained data indicate the protective and cryoprotective effects of TTPEG*10PEG at a concentration of 2%, which suggests the possibility of its use in the technology of intraovarian vitrification of female reproductive cells.

Characterization and Functional Analysis of the 17-Beta Hydroxysteroid Dehydrogenase 2 (hsd17b2) Gene during Sex Reversal in the Ricefield Eel (Monopterus albus).

In mammals, 17-beta hydroxysteroid dehydrogenase 2 (Hsd17b2) enzyme specifically catalyzes the oxidation of the C17 hydroxyl group and efficiently regulates the activities of estrogens and androgens to prevent diseases induced by hormone disorders. However, the functions of the hsd17b2 gene involved in animal sex differentiation are still largely unclear. The ricefield eel (Monopterus albus), a protogynous hermaphroditic fish with a small genome size (2n = 24), is usually used as an ideal model to study the mechanism of sex differentiation in vertebrates. Therefore, in this study, hsd17b2 gene cDNA was cloned and its mRNA expression profiles were determined in the ricefield eel. The cloned cDNA fragment of hsd17b2 was 1230 bp, including an open reading frame of 1107 bp, encoding 368 amino acid residues with conserved catalytic subunits. Moreover, real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR) analysis showed that hsd17b2 mRNA expressed strongly in the ovaries at early developmental stages, weakly in liver and intestine, and barely in testis and other tissues. In particular, hsd17b2 mRNA expression was found to peak in ovaries of young fish and ovotestis at the early stage, and eventually declined in gonads from the late ovotestis to testis. Likewise, chemical in situ hybridization results indicated that the hsd17b2 mRNA signals were primarily detected in the cytoplasm of oogonia and oocytes at stage I-II, subsequently concentrated in the granulosa cells around the oocytes at stage Ⅲ-Ⅳ, but undetectable in mature oocytes and male germ cells. Intriguingly, in ricefield eel ovaries, hsd17b2 mRNA expression could be significantly reduced by 17β-estradiol (E2) or tamoxifen (17β-estradiol inhibitor, E2I) induction at a low concentration (10 ng/mL) and increased by E2I induction at a high concentration (100 ng/mL). On the other hand, both the melatonin (MT) and flutamide (androgen inhibitor, AI) induction could significantly decrease hsd17b2 mRNA expression in the ovary of ricefield eel. This study provides a clue for demonstrating the mechanism of sexual differentiation in fish. The findings of our study imply that the hsd17b2 gene could be a key regulator in sexual differentiation and modulate sex reversal in the ricefield eel and other hermaphroditic fishes.

RpL38 modulates germ cell differentiation by controlling Bam expression in Drosophila testis.

Switching from mitotic spermatogonia to meiotic spermatocytes is critical to producing haploid sperms during male germ cell differentiation. However, the underlying mechanisms of this switch remain largely unexplored. In Drosophila melanogaster, the gene RpL38 encodes the ribosomal protein L38, one component of the 60S subunit of ribosomes. We found that its depletion in spermatogonia severely diminished the production of mature sperms and thus led to the infertility of male flies. By examining the germ cell differentiation in testes, we found that RpL38-knockdown blocked the transition from spermatogonia to spermatocytes and accumulated spermatogonia in the testis. To understand the intrinsic reason for this blockage, we conducted proteomic analysis for these spermatogonia populations. Differing from the control spermatogonia, the accumulated spermatogonia in RpL38-knockdown testes already expressed many spermatocyte markers but lacked many meiosis-related proteins, suggesting that spermatogonia need to prepare some important proteins for meiosis to complete their switch into spermatocytes. Mechanistically, we found that the expression of bag of marbles (bam), a crucial determinant in the transition from spermatogonia to spermatocytes, was inhibited at both the mRNA and protein levels upon RpL38 depletion. We also confirmed that the bam loss phenocopied RpL38 RNAi in the testis phenotype and transcriptomic profiling. Strikingly, overexpressing bam was able to fully rescue the testis abnormality and infertility of RpL38-knockdown flies, indicating that bam is the key effector downstream of RpL38 to regulate spermatogonia differentiation. Overall, our data suggested that germ cells start to prepare meiosis-related proteins as early as the spermatogonial stage, and RpL38 in spermatogonia is required to regulate their transition toward spermatocytes in a bam-dependent manner, providing new knowledge for our understanding of the transition process from spermatogonia to spermatocytes in Drosophila spermatogenesis.

FBXO24 deletion causes abnormal accumulation of membraneless electron-dense granules in sperm flagella and male infertility

Ribonucleoprotein (RNP) granules are membraneless electron-dense structures rich in RNAs and proteins, and involved in various cellular processes. Two RNP granules in male germ cells, intermitochondrial cement and the chromatoid body (CB), are associated with PIWI-interacting RNAs (piRNAs) and are required for transposon silencing and spermatogenesis. Other RNP granules in male germ cells, the reticulated body and CB remnants, are also essential for spermiogenesis. In this study, we disrupted FBXO24, a testis-enriched F-box protein, in mice and found numerous membraneless electron-dense granules accumulated in sperm flagella. Fbxo24 knockout (KO) mice exhibited malformed flagellar structures, impaired sperm motility, and male infertility, likely due to the accumulation of abnormal granules. The amount and localization of known RNP granule-related proteins were not disrupted in Fbxo24 KO mice, suggesting that the accumulated granules were distinct from known RNP granules. Further studies revealed that RNAs and two importins, IPO5 and KPNB1, abnormally accumulated in Fbxo24 KO spermatozoa and that FBXO24 could ubiquitinate IPO5. In addition, IPO5 and KPNB1 were recruited to stress granules, RNP complexes, when cells were treated with oxidative stress or a proteasome inhibitor. These results suggest that FBXO24 is involved in the degradation of IPO5, disruption of which may lead to the accumulation of abnormal RNP granules in sperm flagella.

FBXO24 deletion causes abnormal accumulation of membraneless electron-dense granules in sperm flagella and male infertility.

Ribonucleoprotein (RNP) granules are membraneless electron-dense structures rich in RNAs and proteins, and involved in various cellular processes. Two RNP granules in male germ cells, intermitochondrial cement and the chromatoid body (CB), are associated with PIWI-interacting RNAs (piRNAs) and are required for transposon silencing and spermatogenesis. Other RNP granules in male germ cells, the reticulated body and CB remnants, are also essential for spermiogenesis. In this study, we disrupted FBXO24, a testis-enriched F-box protein, in mice and found numerous membraneless electron-dense granules accumulated in sperm flagella. Fbxo24 knockout (KO) mice exhibited malformed flagellar structures, impaired sperm motility, and male infertility, likely due to the accumulation of abnormal granules. The amount and localization of known RNP granule-related proteins were not disrupted in Fbxo24 KO mice, suggesting that the accumulated granules were distinct from known RNP granules. Further studies revealed that RNAs and two importins, IPO5 and KPNB1, abnormally accumulated in Fbxo24 KO spermatozoa and that FBXO24 could ubiquitinate IPO5. In addition, IPO5 and KPNB1 were recruited to stress granules, RNP complexes, when cells were treated with oxidative stress or a proteasome inhibitor. These results suggest that FBXO24 is involved in the degradation of IPO5, disruption of which may lead to the accumulation of abnormal RNP granules in sperm flagella.

Histone demethylase KDM2A recruits HCFC1 and E2F1 to orchestrate male germ cell meiotic entry and progression

In mammals, the transition from mitosis to meiosis facilitates the successful production of gametes. However, the regulatory mechanisms that control meiotic initiation remain unclear, particularly in the context of complex histone modifications. Herein, we show that KDM2A, acting as a lysine demethylase targeting H3K36me3 in male germ cells, plays an essential role in modulating meiotic entry and progression. Conditional deletion of Kdm2a in mouse pre-meiotic germ cells results in complete male sterility, with spermatogenesis ultimately arrested at the zygotene stage of meiosis. KDM2A deficiency disrupts H3K36me2/3 deposition in c-KIT+ germ cells, characterized by a reduction in H3K36me2 but a dramatic increase in H3K36me3. Furthermore, KDM2A recruits the transcription factor E2F1 and its co-factor HCFC1 to the promoters of key genes required for meiosis entry and progression, such as Stra8, Meiosin, Spo11, and Sycp1. Collectively, our study unveils an essential role for KDM2A in mediating H3K36me2/3 deposition and controlling the programmed gene expression necessary for the transition from mitosis to meiosis during spermatogenesis.

IMPACT OF REAL-LIFE ENVIRONMENTAL EXPOSURES ON REPRODUCTION: Impact of developmental exposures to endocrine-disrupting chemicals on pituitary gland reproductive function.

Endocrine-disrupting chemicals can impact reproduction by affecting the hypothalamic-pituitary-gonadal axis. This review emphasizes the impact of endocrine-disrupting chemicals on pituitary development and function. The pituitary gland is crucial for regulating many physiological systems, including reproduction. Clear evidence suggests that pituitary function can be impaired by exposure to endocrine-disrupting chemicals (EDCs). Humans and animals are exposed to EDCs throughout life, but exposure during critical periods when the pituitary is developing could have more damaging consequences. In this review, we summarize the development of the pituitary gland, including the impact of hormone signals, and describe how in vivo EDC exposure during development might alter pituitary function. These include changes in pituitary hormone, mRNA, and protein expression levels, as well as pituitary cell number and population balance. We focus on reproductive hormone-producing cells as well as other endocrine and pituitary stem/progenitor cells. We reveal the current gaps in knowledge and suggest future directions in terms of understanding the effects of developmental EDC exposure directly on the pituitary gland.

ARID1 is required to regulate and reinforce H3K9me2 in sperm cells in Arabidopsis

Heterochromatin de-condensation in companion gametic cells is conserved in both plants and animals. In plants, microspore undergoes asymmetric pollen mitosis (PMI) to produce a vegetative cell (VC) and a generative cell (GC). Subsequently, the GC undergoes pollen mitosis (PMII) to produce two sperm cells (SC). Consistent with heterochromatin de-condensation in the VC, H3K9me2, a heterochromatin mark, is barely detected in VC. However, how H3K9me2 is differentially regulated during pollen mitosis remains unclear. Here, we show that H3K9me2 is gradually evicted from the VC since PMI but remain unchanged in the GC and SC. ARID1, a pollen-specific transcription factor that facilitates PMII, promotes H3K9me2 maintenance in the GC/SC but slows down its eviction in the VC. The genomic targets of ARID1 mostly overlaps with H3K9me2 loci, and ARID1 recruits H3K9 methyltransferase SUVH6. Our results uncover that differential pattern of H3K9me2 between two cell types is regulated by ARID1 during pollen mitosis.

Chromatin remodeler CHD4 establishes chromatin states required for ovarian reserve formation, maintenance, and germ cell survival.

The ovarian reserve defines female reproductive lifespan, which in humans spans decades due to the maintenance of meiotic arrest in non-growing oocytes (NGO) residing in primordial follicles. Unknown is how the chromatin state of NGOs is established to enable long-term maintenance of the ovarian reserve. Here, we show that a chromatin remodeler, CHD4, a member of the Nucleosome Remodeling and Deacetylase (NuRD) complex, establishes chromatin states required for formation and maintenance of the ovarian reserve. Conditional loss of CHD4 in perinatal mouse oocytes results in acute death of NGOs and depletion of the ovarian reserve. CHD4 establishes closed chromatin at regulatory elements of pro-apoptotic genes to prevent cell death and at specific genes required for meiotic prophase I to facilitate the transition from meiotic prophase I oocytes to meiotic arrested NGOs. In addition, CHD4 establishes closed chromatin at the regulatory elements of pro-apoptotic genes in male germ cells, allowing male germ cell survival. These results demonstrate a role for CHD4 in defining a chromatin state that ensures germ cell survival, thereby enabling the long-term maintenance of both female and male germ cells.

β-aminoisobutyric acid ameliorated type 1 diabetes-induced germ cell toxicity in rat: Studies on the role of oxidative stress and IGF-1/AMPK/SIRT-1 signaling pathway

Diabetes mellitus is known as the “epidemic of the century” due to its global prevalence. Several pre-clinical and clinical studies have shown that male germ cell toxicity is one of the major consequences of diabetes mellitus. Although β-aminoisobutyric acid (BAIBA) has been shown to be advantageous in the diabetic nephropathy and cardiomyopathy, its specific role in the diabetes-induced testicular toxicity remains unknown. In this study, an attempt was made to elucidate the molecular mechanisms of BAIBA-mediated germ cell protection in diabetic rats. Adult male Sprague-dawley rats were subjected to either no treatment (control) or BAIBA (100 mg/kg; BAIBA control) or Streptozotocin (50 mg/kg; diabetic control) or low (25 mg/kg), medium (50 mg/kg) and high (100 mg/kg) doses of BAIBA in diabetic conditions. Significant alterations in sperm related parameters, oxidative stress and apoptotic biomarkers, pancreatic and testicular histology, DNA damage and changes in expression of proteins in testes were found in the diabetic rats. 100 mg/kg of BAIBA significantly reduced the elevated blood glucose levels (P ≤ 0.05), increased body weight (P ≤ 0.01 in the 4th week), lowered malondialdehyde (P ≤ 0.05) and nitrite levels (P ≤ 0.01), elevated testosterone (P ≤ 0.05) and FSH levels (P ≤ 0.05), increased sperm count and motility (P ≤ 0.01), decreased testicular DNA damage (P ≤ 0.001), improved histological features of pancreas and testes, decreased TUNEL positive cells (P ≤ 0.01), decreased RAGE (P ≤ 0.01) and Bax (P ≤ 0.05) expressions and increased SIRT1 (P ≤ 0.05) and Atg 12 (P ≤ 0.05) expressions in the testes. 50 mg/kg of BAIBA partially restored the above-mentioned parameters whereas 25 mg/kg of BAIBA was found to be insignificant in counteracting the toxicity. It is interesting to note that BAIBA protects male germ cell damage in diabetic rats by regulating the IGF-1/AMPK/SIRT-1 signaling pathway.

Exploring Advances in Reproduction and Stem Cell Biology: Highlights from The 24th and 19th International Congresses in Iran.

The 24th and 19th International Congresses on Reproduction and Stem Cell Biology in the Islamic Republic of Iran brought together experts and researchers worldwide to explore the latest advancements in these fields. Different topics were discussed, including such as reproductive health, infertility treatments, stem cell research, and regenerative medicine. This report provides a summary of the congress's key findings by emphasizing pioneer research and technologies that can influence the future of reproduction and stem cell biology programs. The presence of keynote speakers such as Professor Nicolas Rivron, Mohammad Ebrahim Parsanezhad, Ashraf Moini, Abbas Aflatoonian, Hadi Shafiee, Anna Brini, Omid Camron Farokhzad, and Jeffrey Schweitzer added value to the event, which had over 1100 participants from around the world. While foreign speakers were from various countries Iranian speakers mainly came from Tabriz, Isfahan, Shiraz, Babol, and Tehran that all discussed cutting-edge science and successful disease treatments. To ensure a more comprehensive representation, it is suggested that a wider geographic distribution of national and foreign speakers should be considered in future plan.

Testicular Cells Derived Conditioned Medium Supports Germ Cell Differentiation of Human Embryonic Stem Cells.

There are ethical and technical challenges in studying human germ cell development. Therefore, the aim of the study is in vitro differentiation of human embryonic stem cells (hESCs), as pluripotent cells, to the germ cells which is a valuable tool for studying molecular and cellular aspects of gametogenesis and understanding causes of infertility. In this experimental study, two different complete media [Dulbecco's Modified Eagle Medium (DMEM)+20% fetal bovine serum (FBS) and embryoid bodies (EBs) medium; KOSR/HES without basic fibroblast growth factor (bFGF)] were used in the both of test groups using testicular cells derived conditioned medium (TCCM) and control groups spontaneously differentiated (SD). Thereby, EBs from hESCs (Yazd2; 46XY) were cultured in different conditions EB medium; EB medium and conditioned EB medium; EB medium, DMEM, and FBS without conditioning; EB medium, conditioned DMEM, and FBS medium. EBs were collected after 4, 7, and 14 days and their gene expression profiles were assessed and compared to hESCs, as day 0, using IF and relative reverse transcription quantitative polymerase chain reaction (RT-qPCR). An increase in the gametogenesis gene expression level in TCCM groups was showed in comparison with SD groups. Additionally, immunostaining of differentiated cells in all groups showed in vitro gametogenesis (IVG). Our findings showed that human TCCM could be used as a natural niche for in vitro male and female germ cell development. However, further studies are needed to define the factors and metabolites within the human TCCM.

Inherited defects of piRNA biogenesis cause transposon de-repression, impaired spermatogenesis, and human male infertility

piRNAs are crucial for transposon silencing, germ cell maturation, and fertility in male mice. Here, we report on the genetic landscape of piRNA dysfunction in humans and present 39 infertile men carrying biallelic variants in 14 different piRNA pathway genes, including PIWIL1, GTSF1, GPAT2, MAEL, TDRD1, and DDX4. In some affected men, the testicular phenotypes differ from those of the respective knockout mice and range from complete germ cell loss to the production of a few morphologically abnormal sperm. A reduced number of pachytene piRNAs was detected in the testicular tissue of variant carriers, demonstrating impaired piRNA biogenesis. Furthermore, LINE1 expression in spermatogonia links impaired piRNA biogenesis to transposon de-silencing and serves to classify variants as functionally relevant. These results establish the disrupted piRNA pathway as a major cause of human spermatogenic failure and provide insights into transposon silencing in human male germ cells.

Control of epigenomic landscape and development of fetal male germ cells through L-serine metabolism

Sex-specific metabolic characteristics emerge in the mouse germ line after reaching the genital ridges around embryonic day 10.5, coinciding with sexual differentiation. However, the impact of such metabolic characteristics on germ cell development remains unclear. In this study, we observed the specific upregulation in male fetal germ cells of D-3-phosphoglycerate dehydrogenase (PHGDH), the primary enzyme in the serine-glycine-one-carbon metabolism, along with an increase in a downstream metabolite, S-adenosylmethionine (SAM), crucial for protein and nucleic acid methylation. Inhibiting PHGDH in fetal testes resulted in reduced SAM levels in germ cells, accompanied by increases in the number of mouse vasa homolog (MVH/VASA)-positive germ cells and the promyelocytic leukemia zinc finger (PLZF)-positive undifferentiated spermatogonia ratio. Furthermore, PHGDH inhibition led to a decrease in the methylation of histone H3 and DNA, resulting in aberrations in gene expression profiles. In summary, our findings underscore the significant role of certain metabolic mechanisms in the development of male germ cells.

Phenotypic continuum and poor intracytoplasmic sperm injection intracytoplasmic sperm injection prognosis in patients harboring HENMT1 variants.

Small RNAs interacting with PIWI (piRNAs) play a crucial role in regulating transposable elements and translation during spermatogenesis and are essential in male germ cell development. Disruptions in the piRNA pathway typically lead to severe spermatogenic defects and thus male infertility. The HENMT1 gene is a key player in piRNAs primary biogenesis and dysfunction of HENMT1 protein in meiotic and haploid germ cells resulted in the loss of piRNA methylation, piRNA instability, and TE de-repression. Henmt1-knockout mice exhibit a severe oligo-astheno-teratozoospermia (OAT) phenotype, whereas patients with HENMT1 variants display more severe azoospermia phenotypes, ranging from meiotic arrest to hypospermatogenesis. Through whole-exome sequencing (WES) of infertile patient cohorts, we identified two new patients with variants in the HENMT1 gene presenting spermatozoa in their ejcaulate, providing us the opportunity to study spermatozoa from these patients. Investigate the spermatozoa of two patients harboring an HENMT1 variant to determine whether or not these scarce spermatozoa could be used with assisted reproductive technologies. HENMT1 variants identified by WES were validated through Sanger sequencing. Comprehensive semen analysis was conducted, and sperm cells were subjected to transmission electron microscopy for structural examination, in situ hybridization for aneuploidy assessment, and aniline blue staining for DNA compaction status. Subsequently, we assessed their suitability for in vitro fertilization using intracytoplasmic sperm injection (IVF-ICSI). Our investigations revealed a severe OAT phenotype similar to knockout mice, revealing altered sperm concentration, mobility, morphology, aneuploidy and nuclear compaction defects. Multiple IVF-ICSI attempts were also performed, but no live births were achieved. We confirm the crucial role of HENMT1 in spermatogenesis and highlight a phenotypic continuum associated with HENMT1 variants. Unfortunately, the clinical outcome of these genetic predispositions remains unfavorable, regardless of the patient's phenotype. The presence of spermatozoa is insufficient to anticipate ICSI pregnancy success in HENMT1 patients.

Mechanical Remodeling of Nuclear Biomolecular Condensates.

Organism health relies on cell proliferation, migration, and differentiation. These universal processes depend on cytoplasmic reorganization driven notably by the cytoskeleton and its force-generating motors. Their activity generates forces that mechanically agitate the cell nucleus and its interior. New evidence from reproductive cell biology revealed that these cytoskeletal forces can be tuned to remodel nuclear membraneless compartments, known as biomolecular condensates, and regulate their RNA processing function for the success of subsequent cell division that is critical for fertility. Both cytoskeletal and nuclear condensate reorganization are common to numerous physiological and pathological contexts, raising the possibility that mechanical remodeling of nuclear condensates may be a much broader mechanism regulating their function. Here, we review this newfound mechanism of condensate remodeling and venture into the contexts of health and disease where it may be relevant, with a focus on reproduction, cancer, and premature aging.

Novel tetrahydropyran-triazole hybrids with antiproliferative activity against human tumor cells.

A series of new hybrid compounds was prepared combining tetrahydropyran rings with different aromatic systems by means of a 1,2,3-triazole, using a building block strategy. The design of these structures was guided by Lead-Likeness and Molecular Analysis (LLAMA) software, adding modifications to our most potent scaffold (the tetrahydropyran ring) to generate promising "lead-like" candidates, which were subsequently compared against reported anticancer compounds. Our synthesized compounds demonstrated significant antiproliferative activity when compared with the standards cisplatin and 5-fluorouracil, across a panel of six different tumor cell lines. Moreover, compared with our group's previous hybrid compounds, these new structures exhibit similar activity while offering simpler synthesis and greater potential for structural diversification, a fact that was previously an issue. Further investigations on the most active compounds included assessments of reproductive cell survival, inhibition of cell migration, and effects on nuclear morphology, indicating potential diverse mechanisms of action for these compounds. Pharmacokinetic properties were also calculated for the whole series of compounds using the pkCSM online software.