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1.
Andrology ; 2(3): 436-49, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24659586

RESUMO

Melatonin acting through the hypothalamus and pituitary regulates testicular function. In addition, direct actions of melatonin at the testicular level have been recently suggested. We have described that melatonin inhibits androgen production in hamster Leydig cells via melatonin subtype 1a (mel1a) receptors and the local corticotrophin-releasing hormone (CRH) system. The initial events of the melatonin/CRH signalling pathway have also been established. Melatonin and all components of the melatonergic/CRH system were also detected in Leydig cells of infertile men. This study attempted to search for additional targets of melatonin in the human testis, and to investigate the effects of melatonin on proliferation and the oxidative state in these novel target cells. To this aim, evaluation of human testicular biopsies of patients suffering from hypospermatogenesis or Sertoli cell only syndrome and cell culture studies were performed. Melatonergic receptors were found in macrophages (MACs) and mast cells (MCs) of the human testis. In biopsies of patients suffering idiopathic infertility, melatonin testicular concentrations were negatively correlated with MAC number per mm(2) and TNFα, IL1ß and COX2 expression, but positively correlated with the expression of the anti-oxidant enzymes SOD1, peroxiredoxin 1 and catalase. Melatonin inhibited proliferation and the expression of pro-inflammatory cytokines and cyclooxygenase 2 (COX2) in both the human non-testicular THP-1 MAC cell line and primary cell cultures of hamster testicular MACs. In the human HMC-1 MC line, melatonin increased the expression of anti-oxidant enzymes and decreased reactive oxygen species (ROS) generation. The results reveal new testicular targets of melatonin and describe anti-proliferative and anti-inflammatory effects of this hormone on testicular MACs. Furthermore, melatonin might provide protective effects against oxidative stress in testicular MCs.


Assuntos
Infertilidade Masculina/metabolismo , Macrófagos/metabolismo , Mastócitos/metabolismo , Melatonina/metabolismo , Testículo/metabolismo , Adulto , Androgênios/biossíntese , Animais , Anti-Inflamatórios , Antioxidantes/metabolismo , Azoospermia/metabolismo , Catalase/biossíntese , Linhagem Celular , Proliferação de Células , Hormônio Liberador da Corticotropina/metabolismo , Cricetinae , Ciclo-Oxigenase 2/biossíntese , Humanos , Interleucina-1beta/biossíntese , Células Intersticiais do Testículo/metabolismo , Macrófagos/citologia , Masculino , Mastócitos/citologia , Oligospermia/metabolismo , Estresse Oxidativo , Peroxirredoxinas/biossíntese , Espécies Reativas de Oxigênio/análise , Receptores de Melatonina/antagonistas & inibidores , Receptores de Melatonina/metabolismo , Síndrome de Células de Sertoli/metabolismo , Transdução de Sinais , Superóxido Dismutase/biossíntese , Superóxido Dismutase-1 , Fator de Necrose Tumoral alfa/biossíntese
2.
Int J Androl ; 35(6): 793-801, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22640168

RESUMO

Fibrosis, increased amounts of immune cells and expression of COX-2 in the testes of infertility patients provide circumstantial evidence for a specific testicular milieu, in which reactive oxygen species (ROS) could be increased. If ROS level increase and/or ROS scavengers decrease, the resulting testicular oxidative stress may contribute to human male infertility. Primary peritubular cells of the human testis, from men with normal spermatogenesis (HTPCs) and infertile patients (HTPC-Fs), previously allowed us to identify an end product of COX-2 action, a prostaglandin derivative (15dPGJ2), which acts via ROS to alter the phenotype of peritubular cells, at least in vitro. Using testicular biopsies we now found 15dPGJ2 in patients and hence we started exploring the ROS scavenger systems of the human testis. This system includes catalase, DJ-1, peroxiredoxin 1, SOD 1 and 2, glutathione-S-transferase and HMOX-1, which were identified by RT-PCR/sequencing in HTPCs and HTPC-Fs and whole testes. Catalase, DJ-1, peroxiredoxin 1 and SOD 2 were also detected by Western blots and in part by immunohistochemistry in testicular samples. Western blots of cultured cells further revealed that catalase levels, but not peroxiredoxin 1, SOD 2 or DJ-1 levels, are significantly higher in HTPC-Fs than in HTPCs. This particular difference is correlated with the improved ability of HTPC-Fs to handle ROS, which became evident when cells were exposed to 100 µm H(2)O(2). H(2)O(2) induced stronger responses in HTPCs than in HTPC-Fs, which correlates with the lower level of the H(2)O(2)-degrading defence enzyme catalase in HTPCs. The results provide evidence for an adaptation to elevated ROS levels, which must have occurred in vivo and which persist in vitro in HTPC-Fs. Thus, in infertile men with impaired spermatogenesis elevated ROS levels likely exist, at least in the tubular wall.


Assuntos
Sequestradores de Radicais Livres/metabolismo , Infertilidade Masculina/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Testículo/metabolismo , Sequência de Bases , Catalase/metabolismo , Células Cultivadas , Primers do DNA , Humanos , Infertilidade Masculina/patologia , Masculino , Peroxirredoxinas/metabolismo , Reação em Cadeia da Polimerase , Superóxido Dismutase/metabolismo , Testículo/enzimologia , Testículo/patologia
3.
Hum Reprod ; 14(7): 1811-8, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10402395

RESUMO

A series of 10 young sterile men with acephalic spermatozoa or abnormal head-mid-piece attachments is presented. Nine of these patients had 75-100% spermatozoa with minute cephalic ends and 0-25% abnormal head-middle piece attachments. Loose heads ranged between 0-35 for each 100 spermatozoa and normal forms were rare. Two patients were brothers. On ultrastructural examination, the head was generally absent and the middle piece was covered by the plasma membrane. When present, heads implanted at abnormal angles on the middle piece. A testicular biopsy showed abnormal spermiogenesis. The implantation fossa was absent and the flagellar anlage developed independently from the nucleus, resulting in abnormal head-middle piece connections. In one patient azoospermia was induced with testosterone to attempt to increase the normal sperm clone during the rebound phenomenon, but all newly formed spermatozoa were acephalic. In another patient with high numbers of defective head-mid-piece connections, microinjections of spermatozoa resulted in four fertilized oocytes, but syngamy and cleavage did not take place, suggesting an abnormal function of the centrioles. The findings indicate that acephalic spermatozoa arise in the testis as the result of an abnormal neck development during spermiogenesis. The familial incidence and the typical phenotype strongly suggest a genetic origin of the syndrome.


Assuntos
Infertilidade Masculina/genética , Infertilidade Masculina/patologia , Espermatozoides/anormalidades , Adulto , Feminino , Fertilização in vitro , Humanos , Infertilidade Masculina/terapia , Masculino , Microinjeções , Microscopia Eletrônica , Microscopia Eletrônica de Varredura , Fenótipo , Cabeça do Espermatozoide/ultraestrutura , Espermatogênese , Espermatozoides/ultraestrutura , Síndrome , Testículo/patologia , Zigoto/patologia
4.
Fertil Steril ; 70(2): 360-1, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9696236

RESUMO

OBJECTIVE: To report a triplet pregnancy that occurred after intracytoplasmic injection of sperm into cryopreserved oocytes. DESIGN: Case report. SETTING: Instituto de Ginecología y Fertilidad (IFER), Buenos Aires, Argentina. PATIENT: A 36-year-old infertile patient with premature ovarian failure and a previous term pregnancy with fresh donated oocytes. INTERVENTION(S): We administered leuprolide acetate for pituitary down-regulation followed by E2 valerianate in incremental doses until an endometrial lining of >8 mm was observed by ultrasound. Thawing of frozen donated oocytes, intracytoplasmic sperm injection (ICSI), and translaparoscopic fallopian tube ET also were performed. Natural micronized progesterone was administered intravaginally (600 mg/d) before ET. MAIN OUTCOME MEASURE(S): Ultrasound at the 8th week of gestation revealed a triplet pregnancy with active fetal heartbeats. RESULT(S): A triple intrauterine gestation was achieved with the use of microinjection into cryopreserved oocytes. CONCLUSION(S): This case illustrates the feasibility of oocyte cryopreservation for clinical use in the era of ICSI.


Assuntos
Criopreservação , Infertilidade Feminina/terapia , Oócitos , Gravidez Múltipla , Interações Espermatozoide-Óvulo , Trigêmeos , Adulto , Citoplasma , Feminino , Humanos , Masculino , Microinjeções , Gravidez
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