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1.
Ecotoxicol Environ Saf ; 190: 110044, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31869717

RESUMO

Low-energy shock waves (LESWs) have been widely used in the intervention of a subset of diseased tissues and organs with good results. However, it is unclear whether they can be used directly to intervene in the testes. Therefore, the aim of this study was to determine a relatively safe energy density and impulse number for rat testes. A total of 176 male rats were randomly and equally assigned to different intervention groups. Among them, 144 rats were assigned to 18 shock subgroups with different energy densities (0.02, 0.04 and 0.06 mJ/mm2), different impulse numbers (500, 1000 and 1500 impulses) and different shock periods (2 and 8 weeks). The remaining 32 rats were divided into the sham intervention (S) groups and the blank control (N) groups with observation periods of 2 weeks and 8 weeks. One day after the last LESWs intervention, all the rats were weighed, and the concentrations of reproductive endocrine hormones were measured, the semen quality and testicular tissue oxidative stress levels were analyzed, and histomorphology and ultrastructures were observed. We found that there were no significant differences in the whole-body physiological state, testicular tissue morphology, oxidative stress state and sperm quality between the L1 shock group and the corresponding S group and N group (all p˃0.05, respectively). However, the other parameters of the shock groups caused different degrees of damage to the structure and function of rat testes, and the whole-body physiological state was also adversely affected. This study demonstrated that LESWs with an energy density of 0.02 mJ/mm2 and 500 impulses had no adverse effects on the rat testes.


Assuntos
Testículo/efeitos da radiação , Animais , Masculino , Estresse Oxidativo , Ratos , Análise do Sêmen , Espermatozoides/efeitos da radiação , Testículo/anatomia & histologia , Testículo/química , Testículo/ultraestrutura
2.
Theriogenology ; 138: 111-120, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31325741

RESUMO

Multilamellar bodies (MLBs) are produced and secreted by many cell types. In this study, we report the existence and ultrastructure of MLBs that are produced by Leydig cells and identification of telocytes in the testicular interstitium of naked mole rat. This study was performed on both breeder and non-breeder male naked mole rats using light microscopy, transmission electron microscopy, and morphometric approaches. In the testicular interstitium, the most prominent cells were Leydig cells, which contained numerous lipid droplets (LDs) in the cytoplasm. We found that MLBs were associated with the LDs of Leydig cells and were secreted into the extracellular or interstitial environment via exocytosis. After their release from Leydig cells, MLBs localized to the space between Leydig cells near blood vessels and attached to telocytes. We also identified telocytes in the testicular interstitium, and their cellular extensions were distributed throughout the interstitium. MLBs were aligned along the cellular extensions of telocytes, and membrane-to-membrane contact was observed between the cellular extensions of telocytes and MLBs, suggesting that telocytes may play a role in the transport of MLBs within the interstitial space. No ultrastructural differences were found in Leydig cells, telocytes, or MLBs between breeder and non-breeder testes. However, morphometric analysis revealed a significant difference in the number of MLBs between the breeder and non-breeder animals. Furthermore, both selective autophagy of LDs and non-selective autophagy were observed in Leydig cells. Typical features of macrolipophagy were also observed, as a few LDs were entirely enclosed by a limiting membrane. Remarkably, autophagy may be a key factor in the biogenesis of MLBs and steroid hormone production. The appearance of MLBs in the testicular interstitium of naked mole rats could thus be related to lipid storage and trafficking.


Assuntos
Corpos de Inclusão/ultraestrutura , Células Intersticiais do Testículo/citologia , Células Intersticiais do Testículo/ultraestrutura , Ratos-Toupeira , Telócitos/citologia , Testículo , Animais , Autofagia/fisiologia , Células Intersticiais do Testículo/fisiologia , Masculino , Microscopia , Microscopia Eletrônica de Transmissão , Telócitos/ultraestrutura , Testículo/citologia , Testículo/ultraestrutura
3.
Environ Toxicol Pharmacol ; 70: 103194, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31255771

RESUMO

To evaluate the potential testicular toxicity induced by silver nanoparticles (AgNPs) in Sprague Dawley rate. The protocol study was designed as follows: G1: 30 adult male rats were kept as control. G2: 30 adult male rats were administered 5.36 mg/kg of AgNPs orally, twice weekly for six months. G3: 30 adult male rats were administered 13.4 mg/kg of AgNPs orally, twice weekly for six months. The results of hormonal assay revealed that a significant decrease in testosterone level while a significant increase in LH level was obtained. The testicular homogenate showed a significant decrease in SOD activity accompanied by a significant increase in MDA level in both G2 and G3 in comparison with the control in a dose-response relationship. Sperm viability indicates a significant decrease in rats in G2 and G3 groups. A significant decrease in DNA chromatin integrity % was obtained in rats of G3 in comparison with G2 and control. The semithin and TEM sections of the testis of G2 and G3 groups showed Sertoli cells have vacuolations with a disturbance in the arrangement and the staining affinity of spermatogenic cells. The spermatogonia appeared with a moderate electron density of the nucleus and cytoplasm. The acrosome and its cap become oval and light electron dens of spermatid cells.


Assuntos
Nanopartículas Metálicas/toxicidade , Prata/toxicidade , Testículo/efeitos dos fármacos , Animais , Hormônio Foliculoestimulante/sangue , Hormônio Luteinizante/sangue , Masculino , Malondialdeído/metabolismo , Microscopia Eletrônica de Transmissão , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo , Testículo/metabolismo , Testículo/patologia , Testículo/ultraestrutura , Testosterona/sangue
4.
Mol Med Rep ; 19(6): 4955-4963, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31059031

RESUMO

In most cases, exogenous oestradiol benzoate (EB) inhibits spermatogenesis, however, the mechanism underlying this process has not been fully elucidated. The present study investigated the effect of EB on redox equilibrium and glycometabolism in mouse testes. Male Kunming mice were divided into 3 groups and injected with 0, 5 and 10 mg/kg EB, respectively. Histological analysis revealed no sperm and far fewer spermatogenic cells in the testes of EB­treated mice. Additionally, transmission electron microscopy revealed that mitochondria in Sertoli cells were transformed to vacuoles with irregular cristae in the EB­treated group. EB also significantly decreased the activities and mRNA expression of catalase, superoxide dismutase, and glutathione peroxidase and increased the activity of nitric oxide synthase and nitric oxide concentration in the testes compared with the control. These results indicated that oxidative damage was caused by EB treatment. With regard to glycometabolism, ATP content and activities of hexokinase and pyruvate kinase were significantly reduced in the EB­treated group. Although glucose and pyruvate concentrations were significantly increased by EB treatment, levels of lactate, the main energy source of spermatogenic cells, were unchanged. Monocarboxylate transporter 2 (MCT2) and MCT4, which are responsible for lactate transportation, were downregulated by EB. In conclusion, the results of the present study indicated that azoospermia induced by EB in male mice was associated with oxidative damage and the disorder of testicular metabolic cooperation.


Assuntos
Azoospermia/patologia , Estradiol/análogos & derivados , Metaboloma/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Testículo/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Azoospermia/induzido quimicamente , Azoospermia/veterinária , Cromatografia Líquida de Alta Pressão , Regulação para Baixo/efeitos dos fármacos , Estradiol/farmacologia , Transportador de Glucose Tipo 3/genética , Transportador de Glucose Tipo 3/metabolismo , Hexoquinase/genética , Hexoquinase/metabolismo , Masculino , Camundongos , Microscopia Eletrônica , Transportadores de Ácidos Monocarboxílicos/genética , Transportadores de Ácidos Monocarboxílicos/metabolismo , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Fosforilação/efeitos dos fármacos , Células de Sertoli/ultraestrutura , Espermatogênese/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Testículo/metabolismo , Testículo/ultraestrutura
5.
Microsc Res Tech ; 82(9): 1461-1470, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31140214

RESUMO

Pseudochorthippus parallelus parallelus (Zetterstedt, 1821) (Orthoptera, Acrididae) is a widespread species in Europe, and also it is localized in some regions in Turkey such as Bursa, Eskisehir, Ankara, Bolu, Düzce, and Çankiri. The features of the reproductive organs such as the numbers and shapes of testes and follicles can be used as taxonomical characters. For this purpose, the ultrastructural and histological features of testis and vas deferens in P. parallelus parallelus were examined with using light microscope, scanning electron microscope, and transmission electron microscope. The mature P. parallelus parallelus has two conjugated testes produce spermatozoa. Each testis is composed of numerous testis follicles in which different stages of spermatogenesis and spermiogenesis develop. First, spermatocytes are formed by the mitosis division of the germ cells at the distal end of the follicles. Then, spermatocytes form spermatids by meiosis division in the middle region of the follicles. Finally, spermatids are differentiated to spermatozoa at the proximal region of the follicles. After maturation of the spermatozoa, sperm tails come together as the sperm bundles called as spermatodesm. Each follicle is connected to vas deferens via vas efferens to discharging spermatozoa. In spite of some differences, the testes and the vas deferens in P. parallelus parallelus are highly similar to the those of other species, especially Orthopteran species.


Assuntos
Gafanhotos/anatomia & histologia , Gafanhotos/ultraestrutura , Testículo/anatomia & histologia , Testículo/ultraestrutura , Ducto Deferente/anatomia & histologia , Ducto Deferente/ultraestrutura , Animais , Gafanhotos/fisiologia , Masculino , Microscopia , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Espermátides/citologia , Espermatogênese , Testículo/fisiologia , Turquia
6.
J Therm Biol ; 82: 63-69, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31128660

RESUMO

Heat stress has been documented to reduce reproductive performance of female animals through injury to germ cells, with few studies available in male animals. The objectives of this study were to evaluate protective effects of baicalin on testicular tissue damage of mice subjected to heat stress and its related mechanisms. In this experiment, A total of forty mice were divided into four groups, including control group (C), baicalin group (B), heat stressed group (H) and heat stress with baicalin treatment (H + B) group. Morphological changes, activities of antioxidant enzymes and apoptosis-related parameters in the mice testes tissue were monitored. The results showed that the process of spermatogenesis in mice testis was impaired and the cellular apoptosis increased due to acute heat stress at 41 °C. Interestingly, the tissue damage was alleviated with the significant (P < 0.05) increase in the activities of SOD, CAT and GSH-Px enzymes, decrease (P < 0.05) in MDA content and number of cellular apoptosis recorded in mice of H + B group compared with those in mice from H group. In addition, the Fas, FasL and P-JNK protein expressions were significantly (P < 0.05) increased; and apaf-1, caspase-3, -9 were slightly expressed in the H group, while there was no difference in Bcl-2 expression, compared with C, B and H + B groups. The above results clearly indicate that heat stress induces macroscopic/apoptotic and oxidative changes in the testicular tissue of mice; these changes are alleviated by Baicalin through increasing anti-oxidative enzyme activities and possibly through blocking Fas/FasL pathway.


Assuntos
Flavonoides/farmacologia , Resposta ao Choque Térmico/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Testículo/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Proteína Ligante Fas/metabolismo , Masculino , Camundongos , Transdução de Sinais/efeitos dos fármacos , Testículo/citologia , Testículo/metabolismo , Testículo/ultraestrutura , Receptor fas/metabolismo
7.
Front Biosci (Landmark Ed) ; 24: 1316-1329, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-31136981

RESUMO

Blood-testis barrier (BTB) that is constructed by testicular Sertoli cells (SCs) is essential for spermatogenesis. Krüppel-like factor 6 (Klf6), a nuclear transcription regulator, is reported to be associated with tight junction molecules of BTB between SCs during spermatogenesis; however, the specific regulatory role and mechanism of Klf6 in BTB regulation are still unknown. Here, we primarily confirmed the temporal and spatial expression patterns of Klf6 in mouse testes. Then, Klf6 was silenced in mouse cultured SCs using either Klf6-siRNA or Klf6-shRNA lentivirus. We mainly found that: (i) Klf6 was indispensable for the proliferative activity of mouse SCs; (ii) Klf6 regulated the integrity and permeability of BTB; (iii) Klf6 knockdown led to the significant upregulation of Zo-1, Claudin-11 and Vimentin, and downregulation of Claudin-3. Furthermore, Zo-1 and Claudin-3, participated in the tight junction remolding, were determined as targets of transcription factor Klf6 by luciferase assay. In summary, our findings suggest that Klf6 regulates the BTB assembly and disassembly via mainly targeting Zo-1 and Claudin-3 in mouse SCs.


Assuntos
Barreira Hematotesticular/metabolismo , Fator 6 Semelhante a Kruppel/metabolismo , Células de Sertoli/metabolismo , Testículo/metabolismo , Junções Íntimas/metabolismo , Animais , Células Cultivadas , Claudina-3/genética , Claudina-3/metabolismo , Claudinas/genética , Claudinas/metabolismo , Regulação da Expressão Gênica , Fator 6 Semelhante a Kruppel/genética , Masculino , Camundongos Endogâmicos ICR , Microscopia Eletrônica de Transmissão , Interferência de RNA , Espermatogênese/genética , Testículo/ultraestrutura , Vimentina/genética , Vimentina/metabolismo , Proteína da Zônula de Oclusão-1/genética , Proteína da Zônula de Oclusão-1/metabolismo
8.
Environ Sci Pollut Res Int ; 26(16): 16548-16555, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30980376

RESUMO

Despite the widespread use of the insecticide imidacloprid (IMI), a neonicotinoid, there is an urgent need for documenting information related to its acute toxicity. Therefore, this study aims to explore the markers of IMI acute toxicity in the testes of the red palm weevil (Rhynchophorus ferrugineus). The LC50 of IMI was determined at 15.7 ppm for male R. ferrugineus. We assessed biochemical alterations in the testes resulting from treatment with four IMI concentrations (10, 15, 20, and 30 ppm). A reduction in glutathione content and acetylcholine esterase activity followed the IMI concentration in a dependent manner. Catalase activity was inhibited only at 20 ppm, while it increased significantly at 30 ppm. Lipid peroxidation increased steadily as the IMI concentrations increased. Based on ultrastructural analyses of spermiogenic stages, acute IMI toxicity produced swelling and degeneration of spermatid mitochondria indicating structural imbalances in their membranes. Further, abnormal chromatin condensation in nuclei and even loss of sperm were also apparent. This study provides biochemical and ultrastructural indicators for acute toxicity resulting from IMI.


Assuntos
Inseticidas/toxicidade , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade , Testículo/efeitos dos fármacos , Testículo/ultraestrutura , Gorgulhos , Animais , Catalase/antagonistas & inibidores , Catalase/metabolismo , Glutationa/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Espermatogênese/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Espermatozoides/patologia , Testículo/metabolismo , Testes de Toxicidade Aguda
9.
J Steroid Biochem Mol Biol ; 190: 161-172, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30930217

RESUMO

Gonadotropin-releasing hormone 2 receptor (GnRHR2) together with its cognate ligand involves in regulating reproductive behavior. However, little is known concerning the effect of transcription factor steroidogenic factor1 (SF-1) regulation on porcine GnRHR2 gene expression and GnRH2 regulation mechanism in testosterone secretion through GnRHR2. Our study demonstrated that GnRHR2 transcription levels were high in porcine testis. Immunohistochemistry analyses showed that GnRHR2 immunoreactivity was strong in the Leydig cells in boar testes. Two SF-1 binding sites were predicted in GnRHR2 promoter and the second site (-159/-149) was considered to be important for GnRHR2 promoter activity through site-directed mutagenesis. The binding of SF-1 to GnRHR2 promoter was confirmed by electrophoretic mobility shift assays (EMSA) and chromatin immunoprecipitation (ChIP). Overexpression and knockdown experiments revealed that SF-1 could up-regulate porcine GnRHR2 expression. DNA methylation of GnRHR2 promoter CpG island also specifically regulated GnRHR2 expression. Meanwhile, our study also demonstrated GnRH2 treatment promoted the expression of SF-1 and steroidogenic acute regulatory protein (StAR), and that this treatment stimulated cAMP responsive element binding protein (CREB) phosphorylation, regulated the expression of GnRHR2, especially that of GnRHR2-X1, and promoted testosterone secretion in porcine Leydig cells. We speculated that testosterone secretion mediated by GnRH2 and GnRHR2 (mainly GnRHR2-X1) was regulated by phosphorylated CREB interacting with SF-1 to control StAR expression. Taken together, the present study indicates that SF-1 and GnRH2 are the essential regulatory factors for GnRHR2 expression. This study also explores the regulation mechanism of testosterone secretion mediated by GnRH2 and GnRHR2 in porcine Leydig cells.


Assuntos
Hormônio Liberador de Gonadotropina/metabolismo , Receptores LHRH/genética , Suínos/metabolismo , Testículo/metabolismo , Testosterona/metabolismo , Animais , Linhagem Celular , Células Cultivadas , Regulação da Expressão Gênica , Células Intersticiais do Testículo/metabolismo , Masculino , Receptores LHRH/metabolismo , Suínos/genética , Testículo/ultraestrutura
10.
Artigo em Inglês | MEDLINE | ID: mdl-31029056

RESUMO

The Trachinotus ovatus (T. ovatus) reach sexual maturity as late as 4-5 years, and there are no obvious morphology differences between males and females, even at maturity, making the selection of male and female parents for selective breeding difficult. To examine the potential regulatory mechanism of sexual differentiation, we conducted a microRNAs (miRNAs) analysis on the ovaries and testes of T. ovatus. A total of 13,423,691 and 11,734,953 raw reads, representing 91,883,908 and 86,879,726 unique sequences of 18-35 nt length obtained from the ovaries and testes, respectively. After mapping to the T. ovatus transcriptome reference sequence (unpublished data), and comparing the miRNA sequences with the miRBase database, 179 known mature miRNAs and 100 novel miRNAs were identified. Expression analysis showed that, 165 miRNAs were differentially expressed between the ovary and testis. To validate the Illumina results, the expression patterns of the nine most differently expressed miRNAs (dre-miR-7a, dre-miR-7b, dre-miR-153a-3p, dre-miR-144-3p, dre-miR-301a, dre-miR-92a-3p, dre-miR-727-5p, Novel 124, and Novel 190, as well as those of five miRNAs that may relate to gonad development (dre-miR-143, dre-miR-101a, dre-miR-202-5p, dre-let-7c-5p, and dre-miR-181a-5p), were assayed with RT-qPCR. The expression trends for all the miRNAs validated with RT-qPCR were consistent with the next-generation sequencing data. The identification and characterization of the miRNAs differentially expressed between the ovary and the testis of the T. ovatus will increase our understanding of the role of miRNAs in gonad differentiation. These data also facilitate studies on miRNA regulation of teleost reproduction.


Assuntos
Peixes/genética , MicroRNAs/genética , Animais , Feminino , Peixes/crescimento & desenvolvimento , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Sequenciamento de Nucleotídeos em Larga Escala , Masculino , Ovário/metabolismo , Ovário/ultraestrutura , Diferenciação Sexual , Testículo/metabolismo , Testículo/ultraestrutura , Transcriptoma
11.
J Steroid Biochem Mol Biol ; 190: 64-75, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30923019

RESUMO

Testicular aging leads to a decrease in spermatogenesis and steroidogenesis. Vitamin D plays an important role in reproduction by modulating testicular steroidogenesis. As the role of vitamin D3 in testicular steroidogenesis during aging has not been explored, the aim of this study was to evaluate the effects of vitamin D3 on testicular functions in d-gal-induced aged rats. Vitamin D3 treatment on d-gal-induced aged rats resulted in significant improvement in sperm parameters, histoarchitecture, serum testosterone, and rostenedione and estrogen levels. The results of both in vivo and in vitro studies showed that vitamin D3 directly regulates testicular steroidogenic markers. Vitamin D3 treatment also increased CYP19A1 and decreased AR expression in the testes of d-gal-induced aged and normal rats. These results suggest that estrogen-mediated action may be responsible for an improvement in spermatogenesis in aged testis. Furthermore, it may be suggested vitamin D3 has a protective role in the aged testis and unaffected spermatogenesis in normal rats treated with vitamin D3 could be due to a balance between estrogen and androgen action.


Assuntos
Colecalciferol/farmacologia , Esteroides/metabolismo , Testículo/efeitos dos fármacos , Vitaminas/farmacologia , Envelhecimento/efeitos dos fármacos , Animais , Estrogênios/metabolismo , Masculino , Ratos Wistar , Espermatogênese/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Espermatozoides/ultraestrutura , Testículo/metabolismo , Testículo/ultraestrutura , Testosterona/metabolismo
12.
Andrologia ; 51(5): e13251, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30821033

RESUMO

The aim of this study was to elucidate the reproductive toxicity of the coadministration of diltiazem and cyclosporine A or tacrolimus. Testicular development, semen quality, sex hormones and testicular tissues were assessed in unilateral nephrectomised (UN) rats, including the control group, UN group, UN+CsA group, UN+FK506 group, UN+Rapa group, UN+CsA+Dil group and UN+FK506+Dil group. The testicular coefficient, the sperm number and the sperm motility were lower in the treatment groups (except UN+FK506) than in the control and UN groups (all p < 0.05). The lowest sperm number and motility were identified in the UN+CsA+Dil group, followed by the UN+CsA group. The proportion of abnormal sperm was higher in the UN+CsA and UN+CsA+Dil groups than in the control and UN groups, respectively (p < 0.05). The plasma concentrations of sex hormones were changed in the treatment groups. Dil can increase the blood concentrations of CsA and FK506 (◇p < 0.05, ◆p < 0.05). Therapeutic doses of these agents induced morphological changes in the testicular tissue and ultrastructural changes in the testosterone, mesenchymal cells and supporting cells. Our present study suggests that Dil can increase the testicular toxicity of CNIs (calcineurin inhibitors, including CsA and FK506) by enhancing the plasma concentrations of CNIs.


Assuntos
Inibidores de Calcineurina/toxicidade , Bloqueadores dos Canais de Cálcio/toxicidade , Ciclosporina/toxicidade , Diltiazem/toxicidade , Imunossupressores/toxicidade , Tacrolimo/toxicidade , Animais , Modelos Animais de Doenças , Sinergismo Farmacológico , Quimioterapia Combinada/efeitos adversos , Hormônios Esteroides Gonadais/sangue , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/prevenção & controle , Humanos , Rim/cirurgia , Transplante de Rim/efeitos adversos , Masculino , Microscopia Eletrônica de Transmissão , Nefrectomia , Ratos , Ratos Sprague-Dawley , Análise do Sêmen , Motilidade Espermática/efeitos dos fármacos , Testículo/efeitos dos fármacos , Testículo/patologia , Testículo/ultraestrutura
13.
Tissue Cell ; 56: 79-82, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30736908

RESUMO

An ultrastructural study of developing spermatids in sea urchins, Strongylocentrotus intermedius, showed that macroautophagy is involved in formation of residual bodies and removal of excessive cytoplasm by spermatids during spermatogenesis in this species. During late stages of spermatogenesis spermatids sequester excessive cytoplasm into vesicles, surrounded by a double membrane. Subsequently, these vesicles fused to one another into larger vacuoles, up to 1.5 µm in diameter. Finally, the vacuoles transformed into residual bodies by condensing their content into finely granular material of varying electron density, separated from cytoplasm by a single membrane. An immunoelectron microscopic study of late spermatids with the antibodies, raised against microtubule-associated protein 1 A/1B-light chain 3 (LC3), which is a marker of autophagosomes, showed that residual bodies in late spermatids of S. intermedius were LC3-positive.


Assuntos
Autofagia/genética , Ouriços-do-Mar/genética , Espermátides/ultraestrutura , Espermatogênese/genética , Animais , Masculino , Microscopia Eletrônica , Ouriços-do-Mar/crescimento & desenvolvimento , Espermatócitos/ultraestrutura , Espermatogônias/ultraestrutura , Espermatozoides/ultraestrutura , Testículo/ultraestrutura
14.
Cell Tissue Res ; 376(3): 457-470, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30778731

RESUMO

Although individual stages of spermatogenesis in Littorina saxatilis are well studied at the electron microscopic level, the gonad structure and the spatial localization of gametes at different stages of maturation remain unclear. Using differential-interference contrast (DIC) for observations of fresh tissue we show that the mature testis consists of numerous ovoid lobules forming larger lobes. The lobules of intact mature testes of L. saxatilis are filled with randomly arranged multicellular cysts containing gametes at different stages of maturation. Gametes within a cyst are highly synchronized in respect of the differentiation degree. At the same time, no spatial gradient in the arrangement of cysts according to the maturation degree of gametes in them was observed in any of the studied lobules. The male gonads contain cysts with early spermatids, mid, late spermatids, and spermatozoa. Using silver-staining, DAPI, and chromomycin A3 (CMA3) staining, we identify 20 main types of nucleus organization in differentiating sperm. Premature and mature male gonads contain cysts with a mosaic arrangement as well as rare solitary cyst cells, goniablast cysts, or separate spermatogonia in between them. Our data indicate that the testis structure in L. saxatilis cannot be attributed to the tubular type, as previously thought. It corresponds to the lobular cyst type but individual lobules contain cysts with gametes at the same stage of development. It is similar to the testis structure of several fishes, amphibians, and Drosophila melanogaster. This type of the gonad organization has never been described in gastropods before.


Assuntos
Gastrópodes/crescimento & desenvolvimento , Gastrópodes/ultraestrutura , Espermatogênese , Testículo/ultraestrutura , Animais , Masculino , Microscopia Eletrônica/métodos
15.
J Agric Food Chem ; 67(7): 2075-2085, 2019 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-30678458

RESUMO

Gossypol, commonly found in cotton seeds, is hazardous to male reproductive physiology. Although several studies have indicated the toxicity of gossypol in human and animal reproduction, the mechanism of gossypol action in testes has not yet been elucidated. In the present study, we investigated the effects of gossypol in normal mouse testis cells, TM3 and TM4 cells, and in gossypol-treated C57BL/6 mice. We confirmed the antiproliferative effects of gossypol using cell viability assays, with PCNA as a proliferation marker, and cell cycle analysis. We also verified mitochondrial dysfunction and Ca2+ dysregulation in the cytosol of TM3 and TM4 cells, using JC-1 and Fluo-4 dyes. To confirm the cellular signaling mechanisms in testis cell lines, we performed Western blot analysis to assess the changes in MAPK and PI3K/Akt signal transduction, using their pharmacological inhibitors. Moreover, we screened the mRNA expression of genes involved in spermatogenesis and steroidogenesis in TM3 and TM4 cells. We also confirmed the mRNA expression and localization of genes regulating testis function in gossypol-treated and untreated mice testes. Collectively, we suggest that gossypol induces negative effects on testis function by reducing cell viability, mitochondrial membrane potential, and testis development-related genes in vitro and in vivo as well as by modulating the MAPK and PI3K signaling pathways.


Assuntos
Gossipol/toxicidade , Espermatogênese/efeitos dos fármacos , Esteroides/biossíntese , Testículo/efeitos dos fármacos , Testículo/metabolismo , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Células Intersticiais do Testículo/efeitos dos fármacos , Células Intersticiais do Testículo/fisiologia , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , RNA Mensageiro/análise , Células de Sertoli/efeitos dos fármacos , Células de Sertoli/fisiologia , Transdução de Sinais/efeitos dos fármacos , Espermatogênese/genética , Testículo/ultraestrutura
16.
J Histochem Cytochem ; 67(4): 229-243, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30380361

RESUMO

Prolyl endopeptidase (PREP) is an enzyme which cleaves several peptide hormones and neuropeptides on the carboxyl side of proline residues and is involved in many biological processes, including cell proliferation and differentiation, glucose metabolism, learning, memory, and cognitive disorders. PREP has also been identified as a binding partner of tubulin, suggesting the involvement of endopeptidase in microtubule-associate processes, independent of its peptidase activity. Furthermore, several reports have implied PREP participation in both male and female reproduction-associated mechanism. We herein assess a potential association of PREP to the morphogenesis of rat testis, profiling its localization versus tubulin, during the first wave of spermatogenesis and in the adult gonad (from 7 to 60 dpp). We show that, in mitotic phases, PREP shares its localization with tubulin in Sertoli cells, gonocytes, and spermatogonia. Later, during meiosis, both proteins are found in spermatocytes, and in the cytoplasm of Sertoli cells protrusions, surrounding the germ cells, while, during spermiogenesis, they both localize in the cytoplasm of round and elongating spermatids. We also found that this enzyme has a peculiar nuclear localization, in the proliferating cells in all phases of analysis. Finally, they are expressed in the flagellum of mature gametes, as corroborated by additional immunolocalization analysis on both rat and human sperm. Our data support the hypothesis of the fundamental role of PREP in reproduction and in cytoskeletal organization during mammalian testis morphogenesis and gamete progression.


Assuntos
Serina Endopeptidases/análise , Espermatogênese , Espermatozoides/ultraestrutura , Animais , Western Blotting , Imunofluorescência , Humanos , Masculino , Microscopia , Mitose , Ratos , Ratos Sprague-Dawley , Serina Endopeptidases/metabolismo , Espermatozoides/citologia , Espermatozoides/fisiologia , Testículo/citologia , Testículo/fisiologia , Testículo/ultraestrutura , Tubulina (Proteína)/análise , Tubulina (Proteína)/metabolismo
17.
Protoplasma ; 256(3): 693-701, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30460415

RESUMO

Novel biological control methods and integrated pest management strategies are basic requirements for the development of sustainable agriculture. As a result, there is a growing demand for research on the use of plant extracts and natural enemies such as the green lacewing, Ceraeochrysa claveri, as natural pest control methods. Studies have shown that although natural compounds such as neem oil (Azadirachta indica) are effective as pest control strategies, they also cause sublethal effects on nontarget insects, such as C. claveri. The aim of this study was to examine the effects of neem oil on C. claveri testes. C. claveri larvae were fed Diatraea saccharalis eggs, which were pretreated with 0.5%, 1%, and 2% neem oil. Testes were collected from larvae, pupae, and adults and analyzed using light and electron (transmission and scanning) microscopy. Changes in cellular stress and possible cell death were also determined by TUNEL assay and the marker HSP-70. The results showed that neem oil affects the organization and distribution of cysts in the testes and the normal sequence of cyst development, causing a delay in spermatogenesis in the testes of treated insects. Tests for cellular stress and DNA fragmentation indicated there was no cellular alteration in the treated groups. Although neem oil does not induce cell death or changes in HSP-70 expression, this biopesticide negatively impacts the process of spermatogenesis and could decrease the perpetuation of this species in the agroecosystem, indicating that the use of neem oil in association with green lacewings as a biological control should be carefully evaluated.


Assuntos
Glicerídeos/farmacologia , Insetos/fisiologia , Comportamento Predatório , Espermatogênese/efeitos dos fármacos , Terpenos/farmacologia , Animais , Insetos/efeitos dos fármacos , Insetos/ultraestrutura , Larva/efeitos dos fármacos , Larva/ultraestrutura , Masculino , Comportamento Predatório/efeitos dos fármacos , Pupa/efeitos dos fármacos , Pupa/ultraestrutura , Testículo/efeitos dos fármacos , Testículo/ultraestrutura
18.
Dev Biol ; 448(2): 247-259, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30213537

RESUMO

Oikopleura dioica, the only gonochoric species among appendicularians, has a spematozoon with a mid-piece and a conspicuous acrosome that, during fertilisation, undergoes a reaction forming an acrosomal process. To provide more insight into the spermatogenesis of a holoplanktonic tunicate species that completes its life cycle in three to five days, changes in the testis during individual growth have been examined. Spermatogenesis has been subdivided into seven stages based on ultrastructural features during the formation and organisation of the male gonad and the relationships between its macroscopic anatomy and the events of sperm differentiation. Gametes undergo highly synchronised differentiation due to the presence of widespread syncytial structures. Both meiosis and spermiogenesis are brief, and the passage from spermatocytes to spermatids involves a progressive segregation of the germ cells from the syncytial mass with the formation of large cytoplasmic bridges and volume reduction for nucleus compacting and cytoplasmic material changing. The nucleus is small and penetrated anteriorly by a complex acrosome and posteriorly by the distal centriole and part of the flagellum. In spermatids, the single, large mitochondrion appears laterally to the nucleus, and finally, in spermatozoa, it migrates into the mid-piece, wrapping the proximal portion of the axoneme. Because this mitochondrial position is reached only in the late phases of spermatogenesis, it suggests that appendicularians have derived oligopyrenic sperms in which the small nucleus results from adaptation to the assembly of numerous spermatozoa inside the narrow space of the testis compacted in the genital cavity. The formulation of a staging system of gonad development in a model tunicate species known for having the most compacted genome in chordates led to a comparison of histological observations with recent molecular data, improving the characterisation of its biology and life cycle in light of evolutionary implications.


Assuntos
Gônadas/embriologia , Espermatogênese , Urocordados/embriologia , Animais , Diferenciação Celular , Gônadas/citologia , Gônadas/ultraestrutura , Masculino , Meiose , Espermatozoides/citologia , Testículo/citologia , Testículo/embriologia , Testículo/ultraestrutura , Urocordados/citologia
19.
Gen Comp Endocrinol ; 271: 39-48, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30391242

RESUMO

We aim to explore the presence of a novel cell type, telocytes (TCs), in the bank vole testis interstitium following G-coupled membrane estrogen receptor (GPER) signaling withdrawal. In addition, the involvement of interstitial cells in lipid homeostasis was investigated. Bank voles (actively reproducing or regressed) were administered with GPER antagonist (G-15; 50 µg/kg bw) injections. To examine TC distribution, ultrastructure, function, and their connotation in the interstitial tissue lipid balance, electron microscopic observations were implemented. Immunohistochemistry and Western blot for the TC marker, CD34, and lipid balance molecules: leptin, adiponectin, and perilipin were performed. Photoperiod-regulated testis steroidogenic function was estimated via serum melatonin level and intratesticular cholesterol concentrations in immunoenzymatic assays. We demonstrate the presence of TCs in bank vole testis interstitium. Distinctive TC morphology: small cell bodies with very long, slender prolongations, constituting a three-dimensional network around the interstitial cells was seen. Ultrastructurally, scarce mitochondria, a few cisternae of the endoplasmic reticulum, and lipid droplets indicated possible TC implications in lipid homeostasis. Changes in CD34 expression in TCs were seen in relation to GPER disturbances. In GPER-blocked testis, single TCs were present in the LD interstitium when in SD ones they were occasionally absent. Moreover, in TCs of SD voles, a lack of lipid droplets was revealed, likely reflecting attenuated TC function during regression. However, melatonin levels decreased in GPER-blocked LD and SD. Concomitantly, leptin, adiponectin, and perilipin expressions together with cholesterol content varied after blockage. Based on our results we suggest TCs are an important component of the bank vole testis interstitium as they are implicated in ultramorphology maintenance, protein interactions, and lipid homeostasis.


Assuntos
Arvicolinae/metabolismo , Fotoperíodo , Receptores Estrogênicos/metabolismo , Transdução de Sinais , Telócitos/metabolismo , Testículo/metabolismo , Adiponectina/metabolismo , Animais , Antígenos CD34/metabolismo , Arvicolinae/sangue , Biomarcadores/metabolismo , Colesterol/metabolismo , Leptina/metabolismo , Células Intersticiais do Testículo/metabolismo , Masculino , Melatonina/sangue , Melatonina/metabolismo , Perilipina-1/metabolismo , Telócitos/ultraestrutura , Testículo/ultraestrutura
20.
J Gerontol A Biol Sci Med Sci ; 74(6): 860-871, 2019 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-29688289

RESUMO

The trend in parenthood at an older age is increasing for both men and women in developed countries, raising concerns about the reproductive ability, and the consequences for the offspring's health. While reproductive activity in women stops with menopause, a complete cessation of the reproductive potential does not occur in men. Although several studies have been published on the effects of aging on semen parameters and spermatozoa DNA integrity, literature on impact of aging on the testis, particularly cellular, and molecular alterations, has been, so far, limited and controversial. This work discusses the current knowledge on testicular aging in humans and other mammals, covering topics from tissue ultrastructure, to cellular and molecular alterations. Aging affects male reproductive function at multiple levels, from sperm production and quality, to the morphology and histology of the male reproductive system. The morphological and functional changes that occur in the testes result in variations in the levels of many hormones, changes in molecules involved in mitochondrial function, receptors, and signaling proteins. Despite knowing that these age-related alterations occur, their real impact on male fertility and reproductive health are still far from being fully understood, highlighting that research in the field is crucial.


Assuntos
Envelhecimento/fisiologia , Fertilidade/fisiologia , Infertilidade Masculina/fisiopatologia , Testículo/fisiologia , Fatores Etários , Animais , Humanos , Masculino , Idade Paterna , Fatores de Risco , Testículo/ultraestrutura
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