RESUMO
Varicocele (VCL) has been shown to induce severe oxidative stress in the testicular tissue resulting in 35% of males with primary infertility. To compare the exacerbating impacts of varicose on oxidative DNA damage and homeostatic antioxidant reactions in the seminiferous tubules (ST), enclosed and far from varicose vessels. Thirty mature Wistar rats were divided into control and VCL-induced groups. To approve VCL, the testicular diameters, volume, and blood circulation were measured using B-mode and Doppler ultrasonography. Next, to confirm oxidative stress (OS), the global homeostatic antioxidant biomarkers were evaluated. Moreover, the OS-induced oxidative DNA damage and homeostatic antioxidant reactions were compared between STs nearby and far from varicose vessels. Finally, to clarify the DNA damage-induced impact on the cell cycle progression, the global and local expressions of Cyclin D1, Cdk4, and p21 were examined. The VCL-induced group exhibited diminished global antioxidant status (marked with TAC, GPX, SOD, and CAT) and UNG and MPG expression levels. Moreover, the cross-sections of the VCL group represented a prominent reduction in the UNG, MPG, Cyclin D1, and cdk4, and upregulation in the p21 expression levels, more prominently in the STs nearby varicose vessels. Concerning severe oxidative DNA damage and intensive molecular changes in the STs nearby the varicose vessels, they can be considered the main cause of oxidative DNA damage in enclosed tubules. Thus, the varicose-mediated oxidative DNA damage negatively impacts the cell cycle progression in the tubules more intensively in the subcapsular area.
Assuntos
Antioxidantes , Varicocele , Ratos , Masculino , Humanos , Animais , Antioxidantes/farmacologia , Varicocele/metabolismo , Ciclina D1/metabolismo , Ratos Wistar , Testículo/metabolismo , Estresse Oxidativo , Túbulos Seminíferos/metabolismo , Pontos de Checagem do Ciclo CelularRESUMO
Although rodents represent approximately 40% of all living mammalian species, our knowledge regarding their reproductive biology is still scarce. Due to their high vulnerability to environmental changes, wild rodents have become beneficial models for ecological studies. Thus, we aimed to comparatively investigate key functional testis parameters in four sexually mature wild rodent species (A. cursor, A. montensis, N. lasiurus, and O. nigripes). These species belong to the Cricetidae family, which is the most diverse family of rodents in South America, with a total of ~120 species in Brazil. The results found for the gonadosomatic index and the sickled sperm head shape observed strongly suggest that the species here evaluated are promiscuous, prolific, and short-lived. The duration of spermatogenesis was relatively short and varied from ~35-40 days. Both the percentage of seminiferous tubules (ST) in the testis parenchyma (~95-97%) and the number of Sertoli cells (SC) (~48-70 million) per testis gram were very high, whereas a fairly good SC efficiency (~8-13 round spermatids per SC) was observed. In comparison to other mammalian species studied, particularly the rodents of the suborder Myomorpha (i.e. hamsters, rats and mice), the rodents herein investigated exhibited very high (~62-80 million) daily sperm production per testis gram. This impressive spermatogenic efficiency resulted mainly from the short duration of spermatogenesis and quite high values found for the ST percentage in the testis and the SC number per testis gram. We expect that the knowledge here obtained will help conservation programs and the proper management of wildlife.
Assuntos
Arvicolinae/metabolismo , Espermatogênese/fisiologia , Testículo/citologia , Animais , Arvicolinae/fisiologia , Brasil , Células Intersticiais do Testículo/metabolismo , Masculino , Epitélio Seminífero/metabolismo , Túbulos Seminíferos/metabolismo , Células de Sertoli/metabolismo , Espermátides/metabolismo , Espermatozoides/metabolismoRESUMO
Diphylla ecaudata is a hematophagous bat endemic of South America, with food preference for bird blood. Given the lack of information about the reproductive activity of this species, this study aimed to describe the testicular morphology and histomorphometry of D. ecaudata in order to understand its reproductive biology, specially spermatogenesis. The animals were collected in Lajes city, Rio Grande do Norte, Brazil. Following euthanasia, the testes were histologically processed for morphological, morphometric, ultrastructural and immunohistochemical analyses. Their average body weight was 24.64g, with a gonadosomatic index of 0.49%, tubulesomatic index of 0.47%, and a total of 32.20m of seminiferous tubules per gram of testis. The pre-meiotic, meiotic, and post-meiotic phases accounted for 56.20%, 9.30%, and 34.50% of the seminiferous epithelium cycle, respectively. The ultrastructure of spermiogenesis was similar to that described in other mammals and the perforatorium was not observed in the sperm. Androgen receptors were detected in Sertoli cell nuclei and Leydig cell cytoplasm, while aromatase enzyme was detected only in Sertoli cell nuclei. FGF2 and BCL-2 activities were detected in the cytoplasm of zygotene and pachytene primary spermatocytes, as well as round and elongated spermatids. D. ecaudata showed testicular pattern similar to other mammals and characteristics common to other bat species. This species stood out for its high efficiency of Sertoli cells, which presented high capacity to support germ cells, besides the highest sperm production rates among those already recorded. This study is the first step towards the knowledge of D. ecaudata reproduction and the first description of its spermatogenesis.
Assuntos
Biomarcadores/metabolismo , Quirópteros/fisiologia , Espermatogênese , Testículo/fisiologia , Animais , Núcleo Celular/metabolismo , Células Intersticiais do Testículo/citologia , Células Intersticiais do Testículo/metabolismo , Masculino , Túbulos Seminíferos/citologia , Túbulos Seminíferos/metabolismo , Células de Sertoli/citologia , Células de Sertoli/metabolismo , Testículo/anatomia & histologiaRESUMO
The selective serotonin reuptake inhibitor fluoxetine has been used for the treatment of depression. Although sexual disorders have been reported in male patients, few studies have demonstrated the fluoxetine effect on the reproductive histophysiology, and the target of this antidepressant in testes is unknown. We evaluated the impact of short-term treatment with fluoxetine on the adult rat testes, focusing on steroidogenesis by Leydig cells (LC) and androgen-dependent testicular parameters, including Sertoli cells (SC) and peritubular myoid cells (PMC). Since UCHL1 (ubiquitincarboxyl-terminal hydrolase L1) seems to control spermatogenesis, the immunoexpression of this hydrolase was also analyzed. Adult male rats received 20 mg/kg BW of fluoxetine (FG) or saline (CG) for eleven days. In historesin-embedded testis sections, the seminiferous tubule (ST) and epithelial (Ep) areas, and the LC nuclear diameter (LCnu) were measured. The number of abnormal ST, androgen-dependent ST, SC and PMC was quantified. Testicular ß-tubulin levels and peritubular actin immunofluorescence were evaluated. Serum testosterone levels (STL) and steroidogenesis by 17ß-HSD6 immunofluorescence were analyzed, and either UCHL1-immunolabeled or TUNEL-positive germ cells were quantified. In FG, abnormal ST frequency increased whereas ST and Ep areas, androgen-dependent ST number, LCnu, 17ß-HSD6 activity and STL reduced significantly. TUNEL-positive PMC and SC was related to decreased number of these cells and reduction in peritubular actin and ß-tubulin levels. In FG, uncommon UCHL1-immunoexpression was found in spermatocytes and spermatids, and the number of UCHL1-immunolabeled and TUNEL-positive germ cells increased in this group. These findings indicate that LC may be a fluoxetine target in testes, impairing PMC-SC integrity and disturbing spermatogenesis. The increase of UCHL1 in the damaged tubules associated with high incidence of cell death confirms that this hydrolase regulates germ cell death and may be controlled by androgens. The fertility in association with the androgenic status of patients treated with fluoxetine should be carefully evaluated.
Assuntos
Androgênios/metabolismo , Morte Celular/efeitos dos fármacos , Fluoxetina/farmacologia , Células Germinativas/efeitos dos fármacos , Túbulos Seminíferos/efeitos dos fármacos , Ubiquitina Tiolesterase/metabolismo , Animais , Células Germinativas/metabolismo , Hidrolases/efeitos dos fármacos , Hidrolases/metabolismo , Marcação In Situ das Extremidades Cortadas/métodos , Células Intersticiais do Testículo/efeitos dos fármacos , Células Intersticiais do Testículo/metabolismo , Masculino , Ratos , Túbulos Seminíferos/metabolismo , Células de Sertoli/efeitos dos fármacos , Células de Sertoli/metabolismo , Espermatogênese/efeitos dos fármacos , Testículo/efeitos dos fármacos , Testículo/metabolismo , Ubiquitinas/metabolismoRESUMO
Collared peccaries (Tayassu tajacu) present a unique testis cytoarchitecture, where Leydig cells (LC) are mainly located in cords around the seminiferous tubules (ST) lobes. This peculiar arrangement is very useful to better investigate and understand the role of LC in spermatogonial stem cells (SSCs) biology and niche. Recent studies from our laboratory using adult peccaries have shown that the undifferentiated type A spermatogonia (Aund or SSCs) are preferentially located in ST regions adjacent to the intertubular compartment without LC. Following these studies, our aims were to investigate the collared peccary postnatal testis development, from birth to adulthood, with emphasis on the establishment of LC cytoarchitecture and the SSCs niche. Our findings demonstrated that the unique LC cytoarchitecture is already present in the neonate peccary's testis, indicating that this arrangement is established during fetal development. Based on the most advanced germ cell type present at each time period evaluated, puberty (the first sperm release in the ST lumen) in this species was reached at around one year of age, being preceded by high levels of estradiol and testosterone and the end of Sertoli cell proliferation. Almost all gonocytes and SSCs expressed Nanos1, Nanos2 and GFRA1. The analysis of SSCs preferential location indicated that the establishment of SSCs niche is coincident with the occurrence of puberty. Taken together, our findings reinforced and extended the importance of the collared peccary as an animal model to investigate testis function in mammals, particularly the aspects related to testis organogenesis and the SSCs biology and niche.
Assuntos
Artiodáctilos/crescimento & desenvolvimento , Biomarcadores/metabolismo , Espermatogônias/citologia , Nicho de Células-Tronco , Células-Tronco/metabolismo , Testículo/crescimento & desenvolvimento , Animais , Peso Corporal , Hormônios/metabolismo , Masculino , Tamanho do Órgão , Fenótipo , Túbulos Seminíferos/metabolismo , Células de Sertoli/metabolismo , Espermatogênese , Espermatogônias/metabolismo , Testículo/anatomia & histologia , Testículo/metabolismoRESUMO
Understanding critical roles of warming and reanimation is critical to improve the survival of vitrified testicular tissue in domestic cats. The objective was to study structural and functional properties of testicular tissues from prepubertal domestic cats after standard vitrification followed by two warming protocols (directly at 37°C or with a 5-second pre-exposure to 50°C) and three reanimation time points (immediately, 24 h and 5 days post-warming). In Experiment 1, tissues were evaluated for histo-morphology and mitochondrial activity immediately or 24 h after warming protocols. In Experiment 2, cell viability, DNA fragmentation, and germ cell composition were assessed immediately, 24 h, or 5 days after optimal warming. Preservation of seminiferous tubule structure was better using warming at 50°C for five seconds, and survival of somatic as well as germinal cells was higher compared to direct warming at 37°C for one minute. Short term in vitro culture (for reanimation) also proved that cellular composition and functionality were better preserved when warmed for a short time at 50°C. Collective data showed that short warming at 50°C led to better quality of seminiferous tubule structure and cell composition after vitrification and short-term culture. In addition, data suggest clear directions to further understand and optimize testicular tissue survival after fertility preservation procedures.
Assuntos
Fragmentação do DNA , Temperatura Alta/efeitos adversos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Túbulos Seminíferos/metabolismo , Túbulos Seminíferos/patologia , Animais , Gatos , Sobrevivência Celular , Preservação da Fertilidade , MasculinoRESUMO
Methamidophos (MET) is an organophosphate (OP) pesticide widely used in agriculture in developing countries. MET causes adverse effects in male reproductive function in humans and experimental animals, but the underlying mechanisms remain largely unknown. We explored the effect of MET on mice testes (5â¯mg/kg/day/4â¯days), finding that this pesticide opens the blood-testis barrier and perturbs spermatogenesis, generating the appearance of immature germ cells in the epididymis. In the seminiferous tubules, MET treatment changed the level of expression or modified the stage-specific localization of tight junction (TJ) proteins ZO-1, ZO-2, occludin, and claudin-3. In contrast, claudin-11 was barely altered. MET also modified the shape of claudin-11, and ZO-2 at the cell border, from a zigzag to a more linear pattern. In addition, MET diminished the expression of ZO-2 in spermatids present in seminiferous tubules, induced the phosphorylation of ZO-2 and occludin in testes and reduced the interaction between these proteins assessed by co-immunoprecipitation. MET formed covalent bonds with ZO-2 in serine, tyrosine and lysine residues. The covalent modifications formed on ZO-2 at putative phosphorylation sites might interfere with ZO-2 interaction with regulatory molecules and other TJ proteins. MET bonds formed at ZO-2 ubiquitination sites likely interfere with ZO-2 degradation and TJ sealing, based on results obtained in cultured epithelial cells transfected with ZO-2 mutated at a MET target lysine residue. Our results shed light on MET male reproductive toxicity and are important to improve regulations regarding the use of OP pesticides and to protect the health of agricultural workers.
Assuntos
Barreira Hematotesticular/efeitos dos fármacos , Inseticidas/farmacologia , Organofosfatos/farmacologia , Compostos Organotiofosforados/farmacologia , Proteína da Zônula de Oclusão-2/metabolismo , Animais , Barreira Hematotesticular/metabolismo , Claudinas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Ocludina/metabolismo , Fosfoproteínas/metabolismo , Fosforilação/efeitos dos fármacos , Túbulos Seminíferos/efeitos dos fármacos , Túbulos Seminíferos/metabolismo , Espermatogênese/efeitos dos fármacos , Junções Íntimas/efeitos dos fármacos , Junções Íntimas/metabolismo , Proteína da Zônula de Oclusão-1/metabolismoRESUMO
While many studies have shown that pulp mill effluents can affect ovarian physiology in fish, far fewer studies have considered the effects in males. We conducted a lab study to examine the effects of effluent from a Brazilian pulp and paper mill on hepatic and testicular morphology and various aspects of testicular physiology in the zebrafish Danio rerio. Males were exposed to lab water (control) or 4% effluent for 14â¯days. Effluent exposure did not affect testis size as measured by the gonadosomatic index, but contributed to morphological changes in the seminiferous tubules. The number of cysts with histopathological changes was elevated in effluent-exposed fish and the number of cysts containing spermatids was significantly reduced. The testis of effluent exposed fish had reduced levels of lactate, elevated lactate dehydrogenase activity, increased levels of reactive oxygen species and reduced levels of phosphorylated P38 mitogen-activated protein kinase (pP38 MAPK). Separate studies showed that the addition of lactate to testicular tissue incubated in vitro increased the activation of P38 MAPK. Effluent exposure also increased vacuolization, necrosis, apoptosis, hyperemia, and fat infiltration of the hepatocytes. Collectively, we provide evidence of short term effects of pulp mill effluent on testicular and hepatic physiology and biochemistry in the zebrafish.
Assuntos
Indústrias Extrativas e de Processamento , Fígado/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Papel , Testículo/efeitos dos fármacos , Águas Residuárias/toxicidade , Madeira , Animais , Apoptose/efeitos dos fármacos , Brasil , Lactato Desidrogenases/metabolismo , Ácido Láctico/metabolismo , Fígado/citologia , Fígado/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Espécies Reativas de Oxigênio/metabolismo , Túbulos Seminíferos/citologia , Túbulos Seminíferos/efeitos dos fármacos , Túbulos Seminíferos/metabolismo , Testículo/citologia , Testículo/metabolismo , Testes de Toxicidade Aguda , Vacúolos/efeitos dos fármacos , Vacúolos/metabolismo , Peixe-Zebra , Proteínas de Peixe-Zebra/metabolismoRESUMO
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is considered one of the most toxic dioxins. The effects of TCDD are exerted via binding to the aryl hydrocarbon receptor (AhR). The aim of the present study was to evaluate the possible protective effects of resveratrol, an AhR antagonist, against testicular damage caused by TCDD exposure during pregnancy. Pregnant female Sprague-Dawley rats were divided into four groups: a control group; a group treated with 1µgkg-1, p.o., TCDD on Gestational Day (GD) 15; a group treated with 20µgkg-1, p.o., resveratrol on GD10-21; and a group treated with both TCDD and resveratrol. Rats were weighed and killed, and neonatal testes were collected for histopathological analysis on Postnatal Day (PND) 1. At PND90, adult male rats were killed and the testes collected for histopathological analysis and determination of sperm count. Resveratrol had a protective effect against the effects of TCDD on Sertoli cell number in adult and neonate testes, as well as against the effects of TCDD on abnormal seminiferous tubules in adults. Combined administration of TCDD and resveratrol altered the kinetics of spermatogenesis and the proportion of neonatal testicular compartments compared with the control group In addition, combined TCDD and resveratrol treatment decreased seminiferous tubule diameter in adult male rats compared with the control group. In conclusion, resveratrol may protect against some TCDD-induced testicular damage, but, based on the parameters assessed, the administration of resveratrol and TCDD in combination may result in more severe toxicity than administration of either drug alone.
Assuntos
Poluentes Ambientais/toxicidade , Exposição Materna/efeitos adversos , Dibenzodioxinas Policloradas/toxicidade , Efeitos Tardios da Exposição Pré-Natal , Estilbenos/farmacologia , Testículo/efeitos dos fármacos , Fatores Etários , Animais , Animais Recém-Nascidos , Fatores de Transcrição Hélice-Alça-Hélice Básicos/efeitos dos fármacos , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Citoproteção , Feminino , Masculino , Gravidez , Ratos Sprague-Dawley , Receptores de Hidrocarboneto Arílico/efeitos dos fármacos , Receptores de Hidrocarboneto Arílico/metabolismo , Resveratrol , Medição de Risco , Análise do Sêmen , Túbulos Seminíferos/efeitos dos fármacos , Túbulos Seminíferos/metabolismo , Túbulos Seminíferos/patologia , Células de Sertoli/efeitos dos fármacos , Células de Sertoli/metabolismo , Células de Sertoli/patologia , Transdução de Sinais/efeitos dos fármacos , Espermatogênese/efeitos dos fármacos , Estilbenos/toxicidade , Testículo/metabolismo , Testículo/patologiaRESUMO
Glycerol-3-phosphate acyltransferases (GPATs) catalyze the first and rate-limiting step in the de novo glycerolipid synthesis. The GPAT2 isoform differs from the other isoforms because its expression is restricted to male germ cells and cancer cells. It has been recently reported that GPAT2 expression in mouse testis fluctuates during sexual maturation and that it is regulated by epigenetic mechanisms in combination with vitamin A derivatives. Despite progress made in this field, information about GPAT2 role in the developing male germ cells remains unclear. The aim of the present study was to confirm the hypothesis that GPAT2 is required for the normal physiology of testes and male germ cell maturation. The gene was silenced in vivo by inoculating lentiviral particles carrying the sequence of a short-hairpin RNA targeting Gpat2 mRNA into mouse testis. Histological and gene expression analysis showed impaired spermatogenesis and arrest at the pachytene stage. Defects in reproductive fitness were also observed, and the analysis of apoptosis-related gene expression demonstrated the activation of apoptosis in Gpat2-silenced germ cells. These findings indicate that GPAT2 protein is necessary for the normal development of male gonocytes, and that its absence triggers apoptotic mechanisms, thereby decreasing the number of dividing germ cells.