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The influence of weak radio-frequency electromagnetic field (RF-EMF) on living organisms raises new concern because of the Industrial, Scientific, and Medical (ISM) frequency band at 6.78 MHz being promoted by the AirFuel Alliance for mid-range wireless power transfer (WPT) applications and product development. Human exposure to the RF-EMF radiation is unavoidable. In this study, we employed in vitro cell culture and molecular biology approach coupled with integrated transcriptomic and proteomic analyses to uncover the effects of RF-EMF on cells at molecular and cellular levels. Our study has demonstrated that weak RF-EMF is sufficient to exert non-thermal effects on human umbilical vein endothelial cells (HUVEC). Exposure of weak RF-EMF promotes cell proliferation, inhibits apoptosis and deregulates ROS balance. Alteration of several signaling pathways and key enzymes involved in NADPH metabolism, cell proliferation and ferroptosis were identified. Our current study provide solid evidence for the first time that the present safety standards that solely considered the thermal effect of RF-EMF on cell tissue are inadequate, prompt response and modification of existing Guidelines, Standards and Regulation are warranted.
Assuntos
Apoptose , Proliferação de Células , Campos Eletromagnéticos , Células Endoteliais da Veia Umbilical Humana , NADP , Ondas de Rádio , Espécies Reativas de Oxigênio , Humanos , Espécies Reativas de Oxigênio/metabolismo , NADP/metabolismo , Ondas de Rádio/efeitos adversos , Campos Eletromagnéticos/efeitos adversos , Transdução de SinaisRESUMO
The COVID-19 pandemic has resulted in unprecedented plastic pollution from single-used personal protective equipment (PPE), especially face masks, in coastal and marine environments. The secondary pollutants, microplastics from face masks (mask MP), rise concern about their detrimental effects on marine organisms, terrestrial organisms and even human. Using a mouse model, oral exposure to mask MP at two doses, 0.1 and 1 mg MP/day for 21 days, caused no change in animal locomotion, total weight, or sperm counts, but caused damage to sperm motility with increased curvilinear velocity (VCL). The high-dose mask MP exposure caused a significant decrease in linearity (LIN) of sperm motility. Further testicular transcriptomic analysis revealed perturbed pathways related to spermatogenesis, oxidative stress, inflammation, metabolism and energy production. Collectively, our findings substantiate that microplastics from face masks yield adverse effects on mammalian reproductive capacity, highlighting the need for improved plastic waste management and development of environmentally friendly materials.
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Máscaras , Microplásticos , Motilidade dos Espermatozoides , Animais , Masculino , Microplásticos/toxicidade , Camundongos , Motilidade dos Espermatozoides/efeitos dos fármacos , COVID-19 , Testículo/efeitos dos fármacosRESUMO
INTRODUCTION: Growing concerns regarding the reproductive toxicity associated with daily life exposure to micro-/nano-plastics (abbreviated as MNPs) have become increasingly prevalent. In reality, MNPs exposure involves a heterogeneous mixture of MNPs of different sizes rather than a single size. METHODS: In this study, an oral exposure mouse model was used to evaluate the effects of MNPs of four size ranges: 25-30â¯nm, 1-5⯵m, 20-27⯵m, and 125-150⯵m. Adult male C57BL/6â¯J mice were administered environmentally relevant concentrations of 0.1â¯mg MNPs/day for 21 days. After that, open field test and computer assisted sperm assessment (CASA) were conducted. Immunohistochemical analyses of organ and cell type localization of MNPs were evaluated. Testicular transcriptome analysis was carried out to understand the molecular mechanisms. RESULTS: Our result showed that MNPs of different size ranges all impaired sperm motility, with a decrease in progressive sperm motility, linearity and straight-line velocity of sperm movement. Alterations did not manifest in animal locomotion, body weight, or sperm count. Noteworthy effects were most pronounced in the smaller MNPs size ranges (25-30â¯nm and 1-5⯵m). Linear regression analysis substantiated a negative correlation between the size of MNPs and sperm curvilinear activity. Immunohistochemical analysis unveiled the intrusions of 1-5⯵m MNPs, but not 20-27⯵m and 125-150⯵m MNPs, into Leydig cells and testicular macrophages. Further testicular transcriptomic analysis revealed perturbations in pathways related to spermatogenesis, oxidative stress, and inflammation. Particularly within the 1-5⯵m MNPs group, a heightened perturbation in pathways linked to spermatogenesis and oxidative stress was observed. CONCLUSIONS: Our data support the size-dependent impairment of MNPs on sperm functionality, underscoring the pressing need for apprehensions about and interventions against the escalation of environmental micro-/nano-plastics contamination. This urgency is especially pertinent to small-sized MNPs.
Assuntos
Camundongos Endogâmicos C57BL , Microplásticos , Tamanho da Partícula , Motilidade dos Espermatozoides , Testículo , Animais , Masculino , Motilidade dos Espermatozoides/efeitos dos fármacos , Microplásticos/toxicidade , Testículo/efeitos dos fármacos , Testículo/patologia , Testículo/metabolismo , Camundongos , Espermatozoides/efeitos dos fármacos , Nanopartículas/toxicidade , Estresse Oxidativo/efeitos dos fármacosRESUMO
Canonical coxsackievirus and adenovirus receptor (CXADR) is a transmembrane component of cell junctions that is crucial for cardiac and testicular functions via its homophilic and heterophilic interaction. CXADR is expressed in both Sertoli cells and germ cells and is localized mainly at the interface between Sertoli-Sertoli cells and Sertoli-germ cells. Knockout of CXADR in mouse Sertoli cells specifically impairs male reproductive functions, including a compromised blood-testis barrier, apoptosis of germ cells, and premature loss of spermatids. Apart from serving as an important component for cell junctions, recent progress has showed the potential roles of CXADR as a signaling mediator in spermatogenesis. This review summarizes current research progress related to the regulation and role of CXADR in spermatogenesis as well as in pathological conditions. We hope this review provides some future directions and a blueprint to promote the further study on the roles of CXADR.
Assuntos
Receptores Virais , Espermatogênese , Animais , Masculino , Camundongos , Infecções por Coxsackievirus , Enterovirus , Camundongos Knockout , Receptores Virais/metabolismo , Células de Sertoli/fisiologia , Espermátides , TestículoRESUMO
A great variety of endocrine-disrupting chemicals (EDCs) have been used extensively and become widespread in the environment nowadays. Limited mammalian studies have shown that certain EDCs may target chromosome and epigenome of the germline, leading to adverse effects in subsequent generations, despite these progenies having never been exposed to the EDC before. However, the underlying mechanisms of chromosomal changes induced by these pollutants remain poorly known. Using the human ovarian granulosa tumor cell line COV434 as a model, we investigated and compared the transcriptomic changes induced by nine EDCs with diverse chemical structures (i.e. BDE-47, BPA, BP-3, DEHP, DHP, EE2, TCS, TDCPP and NP), to inquire if there is any common epigenetic modification associated with reproductive functions induced by these EDCs. Our results showed that COV434 cells were more responsive to BP-3, NP, DEHP and EE2, and more importantly, these four EDCs altered the expression of gene clusters related to DNA damage response, cell cycle, proliferation, and chromatin remodeling, which can potentially lead to epigenetic modifications and transgenerational inheritance. Furthermore, dysregulation of similar gene clusters was common in DEHP and NP treatments. Bioinformatics analysis further revealed that BP-3 disturbed signaling pathways associated with reproductive functions, whereas alterations in telomere-related pathways were highlighted upon EE2 exposure. Overall, this study highlighted chromatin modifications caused by a class of chemicals which that may potentially lead to epigenetic changes and transgenerational reproductive impairments.
Assuntos
Dietilexilftalato , Disruptores Endócrinos , Poluentes Ambientais , Animais , Humanos , Transcriptoma , Epigênese Genética , Disruptores Endócrinos/toxicidade , Cromatina , Mamíferos/genéticaRESUMO
[This corrects the article DOI: 10.3389/fgene.2021.710143.].
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Humans are regularly and continuously exposed to ionizing radiation from both natural and artificial sources. Cumulating evidence shows adverse effects of ionizing radiation on both male and female reproductive systems, including reduction of testis weight and sperm count and reduction of female germ cells and premature ovarian failure. While most of the observed effects were caused by DNA damage and disturbance of DNA repairment, ionizing radiation may also alter DNA methylation, histone, and chromatin modification, leading to epigenetic changes and transgenerational effects. However, the molecular mechanisms underlying the epigenetic changes and transgenerational reproductive impairment induced by low-dose radiation remain largely unknown. In this study, two different types of human ovarian cells and two different types of testicular cells were exposed to low dose of ionizing radiation, followed by bioinformatics analysis (including gene ontology functional analysis and Ingenuity Pathway Analysis), to unravel and compare epigenetic effects and pathway changes in male and female reproductive cells induced by ionizing radiation. Our findings showed that the radiation could alter the expression of gene cluster related to DNA damage responses through the control of MYC. Furthermore, ionizing radiation could lead to gender-specific reproductive impairment through deregulation of different gene networks. More importantly, the observed epigenetic modifications induced by ionizing radiation are mediated through the alteration of chromatin remodeling and telomere function. This study, for the first time, demonstrated that ionizing radiation may alter the epigenome of germ cells, leading to transgenerational reproductive impairments, and correspondingly call for research in this new emerging area which remains almost unknown.
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Coxsackievirus and adenovirus receptor (CXADR) belongs to immunoglobulin superfamily of cell adhesion molecules. It expresses in most tissues, but displays unique and indispensable functions in some tissues such as heart and testis. CXADR is a multifunctional protein that can serve as a viral receptor, a junction structural protein and a signalling molecule. Thus, it exerts a wide range of functions such as facilitating leukocyte transmigration, regulating barrier function and cell adhesion, promoting EMT transition, and mediating spermatogenesis. This review aims to provide an overview and highlights some recent findings on CXADR in the field with emphasis on studies in the testis, upon which future studies can be designed to delineate the roles and regulation of CXADR in spermatogenesis.
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Receptores Virais , Espermatogênese , Proteína de Membrana Semelhante a Receptor de Coxsackie e Adenovirus/genética , Humanos , Masculino , Receptores Virais/genética , Transdução de SinaisRESUMO
Blood-testis barrier (BTB) and apical ectoplasmic specialization (ES) serve as structural supports for germ cell (GC) development. We demonstrated that the Sertoli cell (SC)-specific coxsackievirus and adenovirus receptor (CXADR) knockout (SC-CXADR-/-), but not the GC-specific knockout, impaired spermatogenesis. An increase in GC apoptosis and premature loss of elongated spermatids were observed in SC-CXADR-/- testes. The BTB function was compromised in SC-CXADR-/- testes with dysregulation of oocludin and zonula occludens-1 expression at the basal compartment of the seminiferous epithelium. An integrated omics analyses confirmed that altered gene ontology terms identified in SC-CXADR-/- testes are highly associated with spermatid development and differentiation, spermatogenesis, and sperm motility and are considered as unique testicular function terms. Leptin, Nasp, Tektin3, Larp 7, and acrosin, which are highly associated with male fertility, were found to be down-regulated in SC-CXADR-/- testes. Based on the data from the omics analyses, we employed the CXADR-deficient SC model to further investigate the molecular mechanisms involved. We unraveled that SC-CXADRs are required for ß-catenin inactivation and cell division cycle protein 42 (Cdc42) activation, resulting in maintaining the integrity and function of the BTB and apical ES as well as inhibiting gene transcription, such as the Myc gene, in the testes. We demonstrated for the first time that CXADR is an important mediator governing ß-catenin and Cdc42 signaling that is essential for spermatogenesis. The molecular mechanisms identified herein may provide new insights to unravel the novel functions and signaling cascades of CXADR in other key CXADR-expressing tissues.-Huang, K., Ru, B., Zhang, Y., Chan, W.-L., Chow, S.-C., Zhang, J., Lo, C., Lui, W.-Y. Sertoli cell-specific coxsackievirus and adenovirus receptor knockout regulates cell adhesion and gene transcription via ß-catenin inactivation and Cdc42 activation.
Assuntos
Adenoviridae/metabolismo , Adesão Celular/fisiologia , Enterovirus/metabolismo , Receptores Virais/fisiologia , Transcrição Gênica/fisiologia , beta Catenina/antagonistas & inibidores , Proteína cdc42 de Ligação ao GTP/metabolismo , Animais , Barreira Hematotesticular/metabolismo , Deleção de Genes , Masculino , Camundongos , Camundongos Knockout , Proteômica , Receptores Virais/genética , Epitélio Seminífero/citologia , Transdução de Sinais , TranscriptomaRESUMO
Recent experiments have reported an effect of weak radiofrequency magnetic fields in the MHz-range on the concentrations of reactive oxygen species (ROS) in living cells. Since the energy that could possibly be deposited by the radiation is orders of magnitude smaller than the energy of molecular thermal motion, it was suggested that the effect was caused by the interaction of RF magnetic fields with transient radical pairs within the cells, affecting the ROS formation rates through the radical pair mechanism. It is, however, at present not entirely clear how to predict RF magnetic field effects at certain field frequency and intensity in nanoscale biomolecular systems. We suggest a possible recipe for interpreting the radiofrequency effects in cells by presenting a general workflow for calculation of the reactive perturbations inside a cell as a function of RF magnetic field strength and frequency. To justify the workflow, we discuss the effects of radiofrequency magnetic fields on generic spin systems to particularly illustrate how the reactive radicals could be affected by specific parameters of the experiment. We finally argue that the suggested workflow can be used to predict effects of radiofrequency magnetic fields on radical pairs in biological cells, which is specially important for wireless recharging technologies where one has to know of any harmful effects that exposure to such radiation might cause.
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Células/efeitos da radiação , Campos Eletromagnéticos/efeitos adversos , Modelos Teóricos , Lesões por Radiação/etiologia , Espécies Reativas de Oxigênio/metabolismo , Células Cultivadas , HumanosRESUMO
The biology of transport of spermatids and spermatid adhesion across the seminiferous epithelium during the epithelial cycle remains largely unexplored. Nonetheless, studies have implicated the role of motor proteins in these cellular events. In this article, we report findings to unravel the role of myosin VIIa, an F-actin-based barbed (+)-end-directed motor protein, to support cellular transport and adhesion in the testis. Using RNA interference to knock down myosin VIIa in Sertoli cells cultured in vitro as a study model was shown to perturb the Sertoli cell tight junction permeability barrier, mediated through disorganization of actin- or microtubule (MT)-based cytoskeletons owing to disruptive changes on the spatiotemporal expression of F-actin or MT-regulatory proteins. Consistent with these in vitro findings, knockdown of myosin VIIa in the testis in vivo also induced disorganization of the actin- and MT-based cytoskeletons across the seminiferous epithelium, mediated by disruptive changes in the spatiotemporal expression of actin- and MT-based regulatory proteins. More important, the transport of spermatids and organelles across the epithelium, as well as cell adhesion, was grossly disrupted. For instance, step 19 spermatids failed to be transported to the adluminal compartment near the tubule lumen to undergo spermiation; in this manner, step 19 spermatids were persistently detected in stage IX and XII tubules, intermingling with step 9 and 12 spermatids, respectively. Also, phagosomes were detected near the tubule lumen in stage I to III tubules when they should have been degraded near the base of the seminiferous epithelium via the lysosomal pathway. In summary, myosin VIIa motor protein was crucial to support cellular transport and adhesion during spermatogenesis.
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Junções Aderentes/metabolismo , Miosina VIIa/fisiologia , Epitélio Seminífero/fisiologia , Células de Sertoli/fisiologia , Espermatogênese , Actinas/metabolismo , Animais , Adesão Celular , Citoesqueleto/metabolismo , Masculino , Fagossomos/metabolismo , Interferência de RNA , Ratos Sprague-Dawley , Espermátides , Proteínas de Junções Íntimas/metabolismoRESUMO
In the mammalian testis, spermatogenesis is dependent on the microtubule (MT)-specific motor proteins, such as dynein 1, that serve as the engine to support germ cell and organelle transport across the seminiferous epithelium at different stages of the epithelial cycle. Yet the underlying molecular mechanism(s) that support this series of cellular events remain unknown. Herein, we used RNAi to knockdown cytoplasmic dynein 1 heavy chain (Dync1h1) and an inhibitor ciliobrevin D to inactivate dynein in Sertoli cells in vitro and the testis in vivo, thereby probing the role of dynein 1 in spermatogenesis. Both treatments were shown to extensively induce disruption of MT organization across Sertoli cells in vitro and the testis in vivo. These changes also perturbed the transport of spermatids and other organelles (such as phagosomes) across the epithelium. These changes thus led to disruption of spermatogenesis. Interestingly, the knockdown of dynein 1 or its inactivation by ciliobrevin D also perturbed gross disruption of F-actin across the Sertoli cells in vitro and the seminiferous epithelium in vivo, illustrating there are cross talks between the two cytoskeletons in the testis. In summary, these findings confirm the role of cytoplasmic dynein 1 to support the transport of spermatids and organelles across the seminiferous epithelium during the epithelial cycle of spermatogenesis.
Assuntos
Dineínas/metabolismo , Espermátides/metabolismo , Espermatogênese/fisiologia , Testículo/metabolismo , Animais , Transporte Biológico/fisiologia , Dineínas/genética , Masculino , Quinazolinonas/farmacologia , Interferência de RNA , Ratos , Células de Sertoli/efeitos dos fármacos , Células de Sertoli/metabolismo , Espermátides/efeitos dos fármacos , Espermatogênese/efeitos dos fármacos , Testículo/efeitos dos fármacosRESUMO
During spermatogenesis, developing elongating/elongated spermatids are highly polarized cells, displaying unique apico-basal polarity. For instance, the heads of spermatids align perpendicular to the basement membrane with their tails pointing to the tubule lumen. Thus, the maximal number of spermatids are packed within the limited space of the seminiferous epithelium to support spermatogenesis. Herein, we reported findings that elongating/elongated spermatids displayed planar cell polarity (PCP) in adult rat testes in which the proximal end of polarized spermatid heads were aligned uniformly across the plane of the seminiferous epithelium based on studies using confocal microscopy and 3-dimensional (D) reconstruction of the seminiferous tubules. We also discovered that spermatid PCP was regulated by PCP protein Vangl2 (Van Gogh-like protein 2) since Vangl2 knockdown by RNAi was found to perturb spermatid PCP. More important, Vangl2 exerted its regulatory effects through changes in the organization of the microtubule (MT)-based cytoskeleton in the seminiferous epithelium. These changes were mediated via the downstream signaling proteins atypical protein kinase C ξ (PKCζ) and MT-associated protein (MAP)/microtubule affinity-regulating kinase 2 (MARK2). These findings thus provide new insights regarding the biology of spermatid PCP during spermiogenesis.
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Polaridade Celular , Citoesqueleto/metabolismo , Microtúbulos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Espermátides/citologia , Espermátides/metabolismo , Testículo/metabolismo , Animais , Citoesqueleto/genética , Masculino , Microtúbulos/genética , Proteínas do Tecido Nervoso/genética , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Testículo/citologiaRESUMO
The blood-testis barrier is a unique ultrastructure in the mammalian testis, located near the basement membrane of the seminiferous tubule that segregates the seminiferous epithelium into the basal and the adluminal (apical) compartment. Besides restricting paracellular and transcellular passage of biomolecules (e.g., paracrine factors, hormones), water, electrolytes, and other substances including toxicants and/or drugs to enter the adluminal compartment of the epithelium, the BTB is an important ultrastructure that supports spermatogenesis. As such, a sensitive and reliable assay to monitor its integrity in vivo is helpful for studying testis biology. This assay is based on the ability of an intact BTB to exclude the diffusion of a small molecule such as sulfo-NHS-LC-biotin (C20H29N4NaO9S2, Mr. 556.59, a water-soluble and membrane-impermeable biotinylation reagent) from the basal to the apical compartment of the seminiferous epithelium. Herein, we summarize the detailed procedures on performing the assay and to obtain semiquantitative data to assess the extent of BTB damage when compared to positive controls, such as treatment of rats with cadmium chloride (CdCl2) which is known to compromise the BTB integrity.
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Biotina/metabolismo , Barreira Hematotesticular/fisiologia , Epitélio Seminífero/metabolismo , Células de Sertoli/metabolismo , Junções Íntimas/metabolismo , Animais , Barreira Hematotesticular/efeitos dos fármacos , Células Cultivadas , Masculino , Ratos , Ratos Sprague-Dawley , Epitélio Seminífero/citologia , Células de Sertoli/citologiaRESUMO
Germ cell differentiation during the epithelial cycle of spermatogenesis is accompanied by extensive remodeling at the Sertoli cell-cell and Sertoli cell-spermatid interface to accommodate the transport of preleptotene spermatocytes and developing spermatids across the blood-testis barrier (BTB) and the adluminal compartment of the seminiferous epithelium, respectively. The unique cell junction in the testis is the actin-rich ectoplasmic specialization (ES) designated basal ES at the Sertoli cell-cell interface, and the apical ES at the Sertoli-spermatid interface. Since ES dynamics (i.e., disassembly, reassembly and stabilization) are supported by actin microfilaments, which rapidly converts between their bundled and unbundled/branched configuration to confer plasticity to the ES, it is logical to speculate that actin nucleation proteins play a crucial role to ES dynamics. Herein, we reported findings that Spire 1, an actin nucleator known to polymerize actins into long stretches of linear microfilaments in cells, is an important regulator of ES dynamics. Its knockdown by RNAi in Sertoli cells cultured in vitro was found to impede the Sertoli cell tight junction (TJ)-permeability barrier through changes in the organization of F-actin across Sertoli cell cytosol. Unexpectedly, Spire 1 knockdown also perturbed microtubule (MT) organization in Sertoli cells cultured in vitro. Biochemical studies using cultured Sertoli cells and specific F-actin vs. MT polymerization assays supported the notion that a transient loss of Spire 1 by RNAi disrupted Sertoli cell actin and MT polymerization and bundling activities. These findings in vitro were reproduced in studies in vivo by RNAi using Spire 1-specific siRNA duplexes to transfect testes with Polyplus in vivo-jetPEI as a transfection medium with high transfection efficiency. Spire 1 knockdown in the testis led to gross disruption of F-actin and MT organization across the seminiferous epithelium, thereby impeding the transport of spermatids and phagosomes across the epithelium and perturbing spermatogenesis. In summary, Spire 1 is an ES regulator to support germ cell development during spermatogenesis.
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Citoplasma/metabolismo , Proteínas dos Microfilamentos/metabolismo , Epitélio Seminífero/metabolismo , Células de Sertoli/metabolismo , Espermátides/metabolismo , Espermatogênese/fisiologia , Animais , Masculino , Ratos , Ratos Sprague-Dawley , Epitélio Seminífero/citologia , Células de Sertoli/citologia , Espermátides/citologia , Junções Íntimas/metabolismoRESUMO
Cell polarity in the adult mammalian testis refers to the polarized alignment of developing spermatids during spermiogenesis and the polarized organization of organelles (e.g., phagosomes, endocytic vesicles, Sertoli cell nuclei, Golgi apparatus) in Sertoli cells and germ cells to support spermatogenesis. Without these distinctive features of cell polarity in the seminiferous epithelium, it is not possible to support the daily production of millions of sperm in the limited space provided by the seminiferous tubules in either rodent or human males through the adulthood. In short, cell polarity provides a novel mean to align spermatids and the supporting organelles (e.g., phagosomes, Golgi apparatus, endocytic vesicles) in a highly organized fashion spatially in the seminiferous epithelium during the epithelial cycle of spermatogenesis. This is analogous to different assembling units in a manufacturing plant such that as developing spermatids move along the "assembly line" conferred by Sertoli cells, different structural/functional components can be added to (or removed from) the developing spermatids during spermiogenesis, so that functional spermatozoa are produced at the end of the assembly line. Herein, we briefly review findings regarding the regulation of cell polarity in the testis with specific emphasis on developing spermatids, supported by an intriguing network of regulatory proteins along a local functional axis. Emerging evidence has suggested that cell cytoskeletons provide the tracks which in turn confer the unique assembly lines in the seminiferous epithelium. We also provide some thought-provoking concepts based on which functional experiments can be designed in future studies.
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Polaridade Celular , Citoesqueleto/metabolismo , Células de Sertoli/metabolismo , Testículo/metabolismo , Animais , Humanos , Masculino , Microtúbulos/metabolismo , Células de Sertoli/citologia , Espermátides/citologia , Espermatogênese , Testículo/citologiaRESUMO
In adult mammalian testes, spermatids, most notably step 17-19 spermatids in stage IV-VIII tubules, are aligned with their heads pointing toward the basement membrane and their tails toward the tubule lumen. On the other hand, these polarized spermatids also align across the plane of seminiferous epithelium, mimicking planar cell polarity (PCP) found in other hair cells in cochlea (inner ear). This orderly alignment of developing spermatids during spermiogenesis is important to support spermatogenesis, such that the maximal number of developing spermatids can be packed and supported by a fixed population of differentiated Sertoli cells in the limited space of the seminiferous epithelium in adult testes. In this review, we provide emerging evidence to demonstrate spermatid PCP in the seminiferous epithelium to support spermatogenesis. We also review findings in the field regarding the biology of spermatid cellular polarity (e.g., head-tail polarity and apico-basal polarity) and its inter-relationship to spermatid PCP. Furthermore, we also provide a hypothetical concept on the importance of PCP proteins in endocytic vesicle-mediated protein trafficking events to support spermatogenesis through protein endocytosis and recycling.
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Polaridade Celular/fisiologia , Transdução de Sinais/fisiologia , Espermátides/fisiologia , Espermatogênese/fisiologia , Animais , Humanos , Masculino , Células de Sertoli/citologia , Células de Sertoli/metabolismo , Espermátides/citologia , Testículo/citologia , Testículo/metabolismoRESUMO
There are over 400 hypoxic zones in the ocean worldwide. Both laboratory and field studies have shown that hypoxia causes endocrine disruption and reproductive impairments in vertebrates. More importantly, our recent study discovered that parental (F0) hypoxia exposure resulted in the transgenerational impairment of sperm quality in the F2 generation through the epigenetic regulation of germ cells. In the present study, we aim to test the hypothesis that the brain, as the major regulator of the brain-pituitary-gonad (BPG) axis, is also involved in the observed transgenerational effect. Using comparative transcriptomic analysis on brain tissues of marine medaka Oryzias melastigma, 45 common differentially expressed genes caused by parental hypoxia exposure were found in the hypoxic group of the F0 and F2 generations, and the transgenerational groups of the F2 generation. The bioinformatic analysis on this deregulated gene cluster further highlighted the possible involvement of the brain in the transgenerational effect of hypoxia on testicular structure, including abnormal morphologies of the epididymis and the seminal vesicle, and degeneration of the seminiferous tubule. This finding is concordant to the result of hematoxylin and eosin staining, which showed the reduction of testicular lobular diameter in the F0 and F2 generations. Our study demonstrated for the first time the involvement of the brain in the transgenerational effect of hypoxia.
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Encéfalo/fisiopatologia , Perfilação da Expressão Gênica , Hipóxia/genética , Oryzias/genética , Oryzias/fisiologia , Testículo/fisiopatologia , Animais , Encéfalo/efeitos dos fármacos , Regulação para Baixo/genética , Feminino , Masculino , Testículo/efeitos dos fármacos , Transcriptoma/genética , Regulação para Cima/genéticaRESUMO
PFOS induces Sertoli cell injury using testicular cells isolated from rodent testes, but it remains unknown if PFOS has similar effects in humans. Herein, we maintained human Sertoli cells in a mitotically active state in vitro, thus enabling transfection experiments that altered gene expression to explore the molecular mechanism(s) underlying toxicant-induced cell injury. Human Sertoli cells obtained from men at ages 15, 23, 36 and 40 were cultured in vitro. These differentiated Sertoli cells remained mitotically active when cultured in the presence of 10% FBS (fetal bovine serum), with a replication time of ~1-3 weeks. At ~80% confluency, they were used for studies including toxicant exposure, immunoblotting, immunofluorescence analysis, tight junction (TJ)-permeability assessment, and overexpression of BTB (blood-testis barrier) regulatory genes such as FAK and its phosphomimetic mutants. PFOS was found to induce Sertoli cell injury through disruptive effects on actin microfilaments and microtubule (MT) organization across the cell cytosol. As a consequence, these cytoskeletal networks failed to support cell adhesion at the BTB. Overexpression of a FAK phosphomimetic and constitutively active mutant p-FAK-Y407E in these cells was capable of rescuing the PFOS-induced injury through corrective cellular organization of cytoskeletal elements. SUMMARY: PFOS induces human Sertoli cell injury which can be rescued by overexpressing p-FAK-Y407E mutant.
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Ácidos Alcanossulfônicos/toxicidade , Fluorocarbonos/toxicidade , Proteína-Tirosina Quinases de Adesão Focal/genética , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Mutação/genética , Células de Sertoli/patologia , Actinas/metabolismo , Adolescente , Adulto , Células Cultivadas , Epitélio/efeitos dos fármacos , Epitélio/metabolismo , Humanos , Masculino , Microtúbulos/efeitos dos fármacos , Microtúbulos/metabolismo , Permeabilidade , Fosforilação/efeitos dos fármacos , Fosfosserina/metabolismo , Transporte Proteico/efeitos dos fármacos , Células de Sertoli/efeitos dos fármacos , Células de Sertoli/metabolismo , Junções Íntimas/efeitos dos fármacos , Junções Íntimas/metabolismo , Adulto JovemRESUMO
A correction to this article has been published and is linked from the HTML version of this paper. The error has been fixed in the paper.