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1.
Crit Rev Eukaryot Gene Expr ; 29(2): 123-126, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31679267

RESUMO

OBJECTIVE: In this study, explored the pathologic mechanism of the contralateral testes impairment in unilaterally cryptorchid rats by investigating the gene expression level. METHODS: Thirty male Sprague-Dawley rats were randomly and evenly divided into two groups: cryptorchid group and control group. Cryptorchidism was induced by surgical relocation. RT-PCR was then applied to examine the mRNA expression level of antioxidant enzymes in descended testes, including glutathione peroxidase (GSH-PX), copper/zinc-superoxide dismutase (Cu/Zn-SOD), and catalase (CAT). The concentration of malondialdehyde (MDA) was determined by spectrophotometry. In addition, germ-cell apoptosis was detected by a terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay. RESULTS: Two weeks after the operation, the mRNA expression levels of GSH-PX and Cu/Zn-SOD in the cryptorchid group were significantly downregulated; the expression of MDA, as well as the number of apoptotic germ cells, significantly increased compared to the control group (p < 0.01). The mRNA expression of CAT did not show significant changes (p > 0.05). CONCLUSION: GSH-PX and SOD were downregulated in the testis contralateral to the undescended testis, leading to the accumulation of reactive oxygen species and germ-cell apoptosis. Our results may provide molecular explanations for the impairment of the descended testis in unilateral cryptorchidism.


Assuntos
Criptorquidismo/genética , Criptorquidismo/fisiopatologia , Regulação Enzimológica da Expressão Gênica , Oxirredutases/genética , Testículo/fisiopatologia , Animais , Criptorquidismo/enzimologia , Masculino , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
2.
PLoS One ; 13(2): e0191806, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29401475

RESUMO

BACKGROUND: The ubiquitin-proteasome system regulate p53, caspase and Bcl-2 family proteins, and is crucial for the degradation of the defective germ cells in testes. Purpose: to evaluate the concentration of ubiquitin carboxyl-terminal hydrolase 1 (UCHL1) in the blood plasma of boys with cryptorchidism and if there is any correlation with patient age. METHODS: Patients-50 boys aged 1-4 years (median = 2,4y.) with unilateral cryptorchidism. Exclusion criteria were: previous human chorionic gonadotropin treatment, an abnormal karyotype, endocrine or immunological disorders or any long-term medication. The control group-50 healthy, age matched boys (aged 1-4 years, median = 2,1y.), admitted to the Pediatric Surgery Department for planned herniotomy. To investigate UCHL1 in blood plasma of boys with cryptorchidism, we used a novel technique Surface PLASMON RESONANCE Imaging (SPRI). RESULTS: The median concentration of UCHL1 in the blood plasma of boys with cryptorchidism, was 5-folds higher than in boys with inguinal hernia, whose testicles were located in the scrotum. We also noticed statistically significant difference between UCHL1 levels in boys with cryptorchidism up to 2 years old, and above 2 years old. Older boys, whose testicles since birth were located in the inguinal pouch or in the abdominal cavity, had higher concentration of UCHL1 in their blood plasma, than boys from younger group. In the group of cryptorchid boys, we also found slightly lower concentrations of INSL3, without statistical significance and no correlation with UCHL1 levels. CONCLUSIONS: Uchl1 concentrations in the blood plasma of boys with cryptorchidism, may reflect the heat-induced apoptosis of germ cells. Higher UCHL1 concentrations in older boys with undescended testicles, probably express intensity of germ cell apoptosis, more extensive when testicles are subjected to heat-stress for longer period. Further analyses of UCHL1 may help to elucidate its role in mechanisms influencing spermatogenesis.


Assuntos
Criptorquidismo/enzimologia , Ubiquitina Tiolesterase/metabolismo , Pré-Escolar , Humanos , Lactente , Masculino
3.
Hormones (Athens) ; 15(2): 277-282, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27376429

RESUMO

CASE PRESENTATION: A 36-year old man, operated on for cryptorchidism at the age of 8 years, was referred to the Outpatient Clinic of Reproductive Endocrinology for investigation of infertility. Clinical examination revealed ambiguous genitalia: penis 4-5 cm, testicular volume 2-3 ml, hypospadias, hypertrophic foreskin and scrotum bifida. Mild hypertension was confirmed. No skeletal malformations were detected. DESIGN: Hormonal and electrolytic determinations as well as semen analysis were conducted. PCR of the coding regions of 17-hydroxylase/17,20 lyase (P450c17) and of P450 oxidoreductase (POR) genes was also performed. RESULTS: Normal levels of electrolytes, low levels of androgens, high levels of gonadotropins and 17-hydroxyprogesterone as well as azoospermia were detected. Karyotype was shown to be 46,XY. Both hCG and ACTH stimulation significantly increased 17-hydroxyprogesterone with no increase in androgens. The diagnosis was congenital adrenal hyperplasia with apparent combined P450c17 and P450c21 deficiency due to mutations in the POR gene. Sequencing of the POR gene revealed: one deletion in exon 12 (Del 1696_1698delGTC >del531Valine) and one missense mutation in exon 7 (A259G) as well as two polymorphisms: rs1057868 (C/T A503V) and rs1057870 (G/A S572S) in exons 12 and 13, respectively. No nucleotide changes were detected in the 8 exons of P450c17. CONCLUSIONS: Molecular findings were consistent with the diagnosis of P450 oxidoreductase deficiency. Despite this severe deficiency, skeletal malformations simulating Antley-Bixler syndrome, which usually characterize the most severe forms, were not confirmed. This discrepancy could be attributed to the differential impact of a POR variant on each one of the P450 enzymes.


Assuntos
Fenótipo de Síndrome de Antley-Bixler/genética , Sistema Enzimático do Citocromo P-450/genética , Análise Mutacional de DNA , Diagnóstico Tardio , Transtorno 46,XY do Desenvolvimento Sexual/genética , Testes Genéticos/métodos , Mutação , Polimorfismo Genético , Adulto , Fenótipo de Síndrome de Antley-Bixler/diagnóstico , Fenótipo de Síndrome de Antley-Bixler/enzimologia , Fenótipo de Síndrome de Antley-Bixler/fisiopatologia , Azoospermia/diagnóstico , Azoospermia/enzimologia , Azoospermia/genética , Criptorquidismo/diagnóstico , Criptorquidismo/enzimologia , Criptorquidismo/genética , Sistema Enzimático do Citocromo P-450/deficiência , Transtorno 46,XY do Desenvolvimento Sexual/diagnóstico , Transtorno 46,XY do Desenvolvimento Sexual/enzimologia , Transtorno 46,XY do Desenvolvimento Sexual/fisiopatologia , Éxons , Predisposição Genética para Doença , Humanos , Cariotipagem , Masculino , Fenótipo , Valor Preditivo dos Testes , Esteroide 17-alfa-Hidroxilase/genética , Esteroide 21-Hidroxilase/genética , Fatores de Tempo
4.
J Clin Lab Anal ; 30(3): 196-9, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-25546171

RESUMO

Cryptorchidism represents a risk factor for infertility and germ cell testicular neoplasia. An increased rate of cryptorchidism has been reported in subjects with Down's syndrome. Cyclic nucleotide phosphodiesterases (PDEs) are important messengers that regulate and mediate a number of cellular responses to extracellular signals, such as neurotransmitters and hormones. PDE4B, cAMP-specific (PDE4B) gene which maps to chromosome 1p31.3 appears to be involved in schizophrenia, chronic psychiatric illness, learning, memory, and mood disturbances. Expression of PDE4 enzymes have been studied in testes of cryptorchid rats. Expression of PDE4B protein examination showed marked degenerative changes in the epithelial lining of the seminiferous tubules. These findings led us to evaluate PDE4 mRNA expression in leukocytes of peripheral blood of five men with DS and cryptorchidism and eleven subjects with DS without cryptorchidism compared with healthy men (controls) by quantitative Real Time PCR (qRT-PCR). This study showed that the PDE4B gene was downexpressed in men with DS and cryptorchidism compared to normal controls and DS without cryptorchidism. A lower expression of the PDE4B gene may be involved in the neurological abnormalities in subjects with Down's syndrome. Moreover, PDE4B gene may be involved in the testicular abnormalities of men with DS and cryptorchidism.


Assuntos
Criptorquidismo/complicações , Criptorquidismo/enzimologia , Síndrome de Down/complicações , Síndrome de Down/enzimologia , Adulto , Estudos de Casos e Controles , Criptorquidismo/genética , AMP Cíclico , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/genética , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/metabolismo , Síndrome de Down/genética , Humanos , Masculino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
5.
PLoS One ; 9(7): e100967, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24983376

RESUMO

A Disintegrin And Metalloproteinase with ThromboSpondin motifs16 (ADAMTS-16) is a member of a family of metalloproteinases. Using a novel zinc-finger nuclease based gene-edited rat model harboring a targeted mutation of the Adamts16 locus, we previously reported this gene to be linked to blood pressure regulation. Here we document our observation with this model that Adamts16 is essential for normal development of the testis. Absence of Adamts16 in the homozygous Adamts16mutant males resulted in cryptorchidism and male sterility. Heterozygous Adamts16mutant males were normal, indicating that this is a recessive trait. Testes of homozygous Adamts16mutant males were significantly smaller with significant histological changes associated with the lack of sperm production. Temporal histological assessments of the testis demonstrated that the seminiferous tubules did not support active spermatogenesis, but progressively lost germ cells, accumulated vacuoles and did not have any sperm. These observations, taken together with our previous report of renal abnormalities observed with the same Adamts16mutant rats, suggest an important mechanistic link between Adamts16 and the functioning of the male genitourinary system.


Assuntos
Proteínas ADAM/genética , Criptorquidismo/genética , Loci Gênicos , Infertilidade Masculina/genética , Mutação , Espermatogênese , Animais , Criptorquidismo/enzimologia , Criptorquidismo/patologia , Infertilidade Masculina/enzimologia , Infertilidade Masculina/patologia , Rim/anormalidades , Masculino , Ratos
8.
J Biol Chem ; 288(31): 22399-407, 2013 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-23792966

RESUMO

The mannose-binding lectin associated-protease-3 (MASP-3) is a member of the lectin pathway of the complement system, a key component of human innate and active immunity. Mutations in MASP-3 have recently been found to be associated with Carnevale, Mingarelli, Malpuech, and Michels (3MC) syndrome, a severe developmental disorder manifested by cleft palate, intellectual disability, and skeletal abnormalities. However, the molecular basis for MASP-3 function remains to be understood. Here we characterize the substrate specificity of MASP-3 by screening against a combinatorial peptide substrate library. Through this approach, we successfully identified a peptide substrate that was 20-fold more efficiently cleaved than any other identified to date. Furthermore, we demonstrated that mutant forms of the enzyme associated with 3MC syndrome were completely inactive against this substrate. To address the structural basis for this defect, we determined the 2.6-Å structure of the zymogen form of the G666E mutant of MASP-3. These data reveal that the mutation disrupts the active site and perturbs the position of the catalytic serine residue. Together, these insights into the function of MASP-3 reveal how a mutation in this enzyme causes it to be inactive and thus contribute to the 3MC syndrome.


Assuntos
Anormalidades Múltiplas/enzimologia , Blefaroptose/enzimologia , Anormalidades Craniofaciais/enzimologia , Craniossinostoses/enzimologia , Criptorquidismo/enzimologia , Cristalografia por Raios X/métodos , Anormalidades do Olho/enzimologia , Cardiopatias Congênitas/enzimologia , Luxação Congênita de Quadril/enzimologia , Serina Proteases Associadas a Proteína de Ligação a Manose/metabolismo , Estrabismo/enzimologia , Músculos Abdominais/anormalidades , Músculos Abdominais/enzimologia , Deficiências do Desenvolvimento/enzimologia , Ativação Enzimática , Humanos , Serina Proteases Associadas a Proteína de Ligação a Manose/química , Modelos Moleculares , Conformação Proteica , Especificidade por Substrato
11.
J Immunol ; 189(8): 3957-69, 2012 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-22966085

RESUMO

The lectin pathway of complement is an important component of innate immunity. Its activation has been thought to occur via recognition of pathogens by mannan-binding lectin (MBL) or ficolins in complex with MBL-associated serine protease (MASP)-2, followed by MASP-2 autoactivation and cleavage of C4 and C2 generating the C3 convertase. MASP-1 and MASP-3 are related proteases found in similar complexes. MASP-1 has been shown to aid MASP-2 convertase generation by auxiliary C2 cleavage. In mice, MASP-1 and MASP-3 have been reported to be central also to alternative pathway function through activation of profactor D and factor B. In this study, we present functional studies based on a patient harboring a nonsense mutation in the common part of the MASP1 gene and hence deficient in both MASP-1 and MASP-3. Surprisingly, we find that the alternative pathway in this patient functions normally, and is unaffected by reconstitution with MASP-1 and MASP-3. Conversely, we find that the patient has a nonfunctional lectin pathway, which can be restored by MASP-1, implying that this component is crucial for complement activation. We show that, although MASP-2 is able to autoactivate under artificial conditions, MASP-1 dramatically increases lectin pathway activity at physiological conditions through direct activation of MASP-2. We further demonstrate that MASP-1 and MASP-2 can associate in the same MBL complex, and that such cocomplexes are found in serum, providing a scenario for transactivation of MASP-2. Hence, in functional terms, it appears that MASP-1 and MASP-2 act in a manner analogous to that of C1r and C1s of the classical pathway.


Assuntos
Anormalidades Múltiplas/enzimologia , Blefaroptose/enzimologia , Via Alternativa do Complemento/imunologia , Lectina de Ligação a Manose da Via do Complemento/imunologia , Anormalidades Craniofaciais/enzimologia , Craniossinostoses/enzimologia , Criptorquidismo/enzimologia , Anormalidades do Olho/enzimologia , Cardiopatias Congênitas/enzimologia , Luxação Congênita de Quadril/enzimologia , Serina Proteases Associadas a Proteína de Ligação a Manose/fisiologia , Estrabismo/enzimologia , Músculos Abdominais/anormalidades , Músculos Abdominais/enzimologia , Músculos Abdominais/imunologia , Anormalidades Múltiplas/genética , Anormalidades Múltiplas/imunologia , Animais , Blefaroptose/genética , Blefaroptose/imunologia , Códon sem Sentido , Via Alternativa do Complemento/genética , Lectina de Ligação a Manose da Via do Complemento/genética , Anormalidades Craniofaciais/genética , Anormalidades Craniofaciais/imunologia , Craniossinostoses/genética , Craniossinostoses/imunologia , Criptorquidismo/genética , Criptorquidismo/imunologia , Deficiências do Desenvolvimento/enzimologia , Deficiências do Desenvolvimento/genética , Deficiências do Desenvolvimento/imunologia , Anormalidades do Olho/genética , Anormalidades do Olho/imunologia , Cardiopatias Congênitas/genética , Cardiopatias Congênitas/imunologia , Luxação Congênita de Quadril/genética , Luxação Congênita de Quadril/imunologia , Humanos , Serina Proteases Associadas a Proteína de Ligação a Manose/genética , Estrabismo/genética , Estrabismo/imunologia , Ativação Transcricional/genética , Ativação Transcricional/imunologia
12.
Arch Dis Child ; 95(4): 296-301, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20335238

RESUMO

OBJECTIVE: Mitochondrial disturbances of energygenerating systems in childhood are a heterogeneous group of disorders. The aim of this multi-site survey was to characterise the natural course of a novel mitochondrial disease with ATP synthase deficiency and mutation in the TMEM70 gene. METHODS: Retrospective clinical data and metabolic profiles were collected and evaluated in 25 patients (14 boys, 11 girls) from seven European countries with a c.317-2A-->G mutation in the TMEM70 gene. RESULTS: Severe muscular hypotonia (in 92% of newborns), apnoic spells (92%), hypertrophic cardiomyopathy (HCMP; 76%) and profound lactic acidosis (lactate 5-36 mmol/l; 92%) with hyperammonaemia (100-520 micromol/l; 86%) were present from birth. Ten patients died within the first 6 weeks of life. Most patients surviving the neonatal period had persisting muscular hypotonia and developed psychomotor delay. HCMP was non-progressive and even disappeared in some children. Hypospadia was present in 54% of the boys and cryptorchidism in 67%. Increased excretion of lactate and 3-methylglutaconic acid (3-MGC) was observed in all patients. In four surviving patients, life-threatening hyperammonaemia occurred during childhood, triggered by acute gastroenteritis and prolonged fasting. CONCLUSIONS: ATP synthase deficiency with mutation in TMEM70 should be considered in the diagnosis and management of critically ill neonates with early neonatal onset of muscular hypotonia, HCMP and hypospadias in boys accompanied by lactic acidosis, hyperammonaemia and 3-MGC-uria. However, phenotype severity may vary significantly. The disease occurs frequently in the Roma population and molecular-genetic analysis of the TMEM70 gene is sufficient for diagnosis without need of muscle biopsy in affected children.


Assuntos
Proteínas de Membrana/genética , Encefalomiopatias Mitocondriais/genética , Proteínas Mitocondriais/genética , Mutação , Idade de Início , Criptorquidismo/enzimologia , Criptorquidismo/genética , Feminino , Humanos , Hiperamonemia/enzimologia , Hiperamonemia/genética , Hipospadia/enzimologia , Hipospadia/genética , Lactente , Recém-Nascido , Masculino , Encefalomiopatias Mitocondriais/enzimologia , ATPases Mitocondriais Próton-Translocadoras/deficiência , Fenótipo , Estudos Retrospectivos
13.
Urology ; 76(1): 67-72, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19942269

RESUMO

OBJECTIVES: To characterize aldo-keto reductase 1C3 (AKR1C3) expression in surgically-removed cryptorchid testes. Human AKR1C3 is a monomeric, cytoplasmic, multifunctional enzyme that reduces ketosteroids, ketoprostaglandins, and lipid aldehydes. AKR1C3 expression has been demonstrated in normal adult Leydig cells and peritubular fibromyocytes. No prior studies have evaluated AKR1C3 expression patterns across different age groups. METHODS: Surgically excised cryptorchid testes were subjected to hematoxylin-eosin evaluation to review overall testicular pathology. These samples were then evaluated for AKR1C3 distribution via immunohistochemical staining with a monospecific AKR1C3 monoclonal antibody. Single-pathologist grading of AKR1C3 expression was correlated with clinical presentations. RESULTS: A total of 16 cryptorchid testes were identified from the 2000 to present. Median age at the time of surgery was 9 years (range, 1-17). The testes were excised due to atrophy, poor tissue consistency, and short spermatic cord length. AKR1C3 expression was identified at all ages in fibromyocytes surrounding the testicular tubules. Leydig cell expression was absent at Tanner stages 1 and 2, while strong expression was found at Tanner stage 3 and beyond. No AKR1C3 expression was seen in germ cells at any stage. AKR1C3 expression was identified in 18%-26% of Sertoli cells in patients at Tanner stages 2 and beyond. CONCLUSIONS: AKR1C3 expression occurs in a Tanner stage dependent-fashion. Pre- and peri-pubertal changes appear to promote expression of the enzyme in Leydig cells. In contrast to the normal adult testis, the pediatric cryptorchid testis reveals AKR1C3 expression in Sertoli cells. Additional studies are warranted to determine the involvement of AKR1C3 in testicular descent and development.


Assuntos
3-Hidroxiesteroide Desidrogenases/biossíntese , Criptorquidismo/enzimologia , Hidroxiprostaglandina Desidrogenases/biossíntese , Adolescente , Membro C3 da Família 1 de alfa-Ceto Redutase , Criança , Pré-Escolar , Criptorquidismo/etiologia , Humanos , Lactente , Masculino , Puberdade
14.
J Urol ; 180(3): 1116-20, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18639287

RESUMO

PURPOSE: We demonstrated that infertility develops in most patients with steroid 5alpha-reductase 2 deficiency. MATERIALS AND METHODS: We compared the testicular histopathology of boys with steroid 5alpha-reductase 2 deficiency to that of boys with isolated bilateral cryptorchidism. RESULTS: Testes with steroid 5alpha-reductase 2 deficiency lacked spermatocytes but had Ad spermatogonia and a normal germ cell count. In contrast, bilateral cryptorchid testes had severe germ cell depletion and the majority lacked Ad spermatogonia. CONCLUSIONS: In patients with steroid 5alpha-reductase 2 deficiency the impaired second step of germ cell maturation results in defective transformation of spermatogonia into spermatocytes. The position of the undescended testis appears to have no major pathological impact on the development of germ cells in patients with steroid 5alpha-reductase 2 deficiency.


Assuntos
Colestenona 5 alfa-Redutase/deficiência , Criptorquidismo/enzimologia , Infertilidade Masculina/enzimologia , Criança , Pré-Escolar , Criptorquidismo/patologia , Criptorquidismo/cirurgia , Humanos , Lactente , Masculino , Fenótipo , Contagem de Espermatozoides , Espermatogênese/fisiologia , Espermatozoides/patologia
15.
Toxicol Sci ; 105(2): 360-7, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18621746

RESUMO

Phenotype results from interactions between genetics and environment, but for most environmental chemical exposures, such interactions are theoretical. The phenotypic response of the testis to in utero dibutyl phthalate (DBP) exposure was compared between two strains of Long-Evans (LE) rats, the orl substrain with inherited cryptorchidism and an outbred (wt) strain. orl and wt LE rats were exposed daily between gestational day (GD) 12 and GD21 to DBP dose levels ranging from 50 to 200 mg/kg by oral gavage and sensitive phthalate testicular end points examined at either GD19, GD21, or postnatal day (PND) 21. At 50 mg/kg DBP, GD19 expression of Cyp17a1, Insl3, and Scarb1 was significantly reduced in orl but not wt testis. At GD21, statistically significant differential strain effects (orl more sensitive than wt) were observed for testicular expression of Scarb1 at 50 and 200 mg/kg DBP and Star at 200 mg/kg DBP. Similarly, DBP exposure disproportionately increased GD21 seminiferous cord diameters and numbers of multinucleated germ cells in the orl strain. At PND21, body weight-corrected testis weights were lowered significantly by DBP exposure at all dose levels in the orl strain but not in wt rats. While the frequency of undescended testes after 200 mg/kg DBP exposure in the orl strain appeared increased, these data were not statistically significant. These results demonstrated enhanced sensitivity of the orl rat to phthalate exposure as compared to its parent strain, a potentially important model of the effects of gene-environment interaction on development of male reproductive malformations.


Assuntos
Criptorquidismo/embriologia , Dibutilftalato/toxicidade , Efeitos Tardios da Exposição Pré-Natal , Testículo/efeitos dos fármacos , Animais , Peso Corporal , Criptorquidismo/enzimologia , Criptorquidismo/genética , Criptorquidismo/patologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Genótipo , Idade Gestacional , Insulina/metabolismo , Masculino , Tamanho do Órgão , Fenótipo , Fosfoproteínas/metabolismo , Gravidez , Proteínas/metabolismo , Ratos , Ratos Long-Evans , Receptores Depuradores Classe B/metabolismo , Esteroide 17-alfa-Hidroxilase/metabolismo , Testículo/embriologia , Testículo/enzimologia , Testículo/patologia
16.
Exp Anim ; 56(2): 71-7, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17460351

RESUMO

Ubiquitination is required throughout all developmental stages of mammalian spermatogenesis. The two ubiquitin C-terminal hydrolase (UCH) enzymes, UCH-L1 and UCH-L3, deubiquitinate ubiquitin-protein conjugates and control the cellular balance of ubiquitin. These two UCH isozymes have 52% amino acid identity and share significant structural similarity. A new function of these two closely related UCH enzymes during spermatogenesis which is associated with germ cell apoptosis has been analyzed. Apoptosis, in general, is thought to be partly regulated by the ubiquitin-proteasome system. During spermatogenesis, apoptosis controls germ cell numbers and eliminates defective germ cells to facilitate testicular homeostasis. In this paper, I review the distinct function of the two UCH isozymes in the testis of gad and Uchl3 knockout mice, which are strongly but reciprocally expressed during spermatogenesis. In addition, the importance of UCHL1-dependent apoptosis for normal spermatogenesis and sperm quality control is discussed.


Assuntos
Apoptose/fisiologia , Cisteína Endopeptidases/metabolismo , Células Germinativas/enzimologia , Espermatogênese/fisiologia , Ubiquitina Tiolesterase/metabolismo , Animais , Criptorquidismo/enzimologia , Cisteína Endopeptidases/deficiência , Cisteína Endopeptidases/genética , Inativação Gênica , Células Germinativas/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ubiquitina/metabolismo , Ubiquitina Tiolesterase/deficiência , Ubiquitina Tiolesterase/genética
18.
Cell Biochem Funct ; 25(5): 515-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-16933204

RESUMO

Sarco(endo)plasmic reticulum Ca(2+)-ATPase (SERCA) and plasmalemmal Ca(2+)-ATPase (PMCA) activities in cremaster muscles and sacs, which have been subjected to different autonomic tonuses, were determined and compared. Samples of cremaster muscles and sacs associated with male or female inguinal hernia, hydrocele or undescended testis were obtained from children during operations and activities of SERCA and PMCA were determined. While highest SERCA and PMCA activities were encountered among cremaster muscles and sacs associated with undescended testis, least activities were encountered among structures associated with hydrocele. The alterations in SERCA and PMCA activities in cremaster muscles associated with undescended testis appear to reflect the attempts at maintaining the levels of cytosolic calcium. Despite similar total calcium contents, lower SERCA and PMCA activities were found in sacs associated with hydrocele compared to those associated with undescended testis suggest a difference among the levels of cytosolic calcium.


Assuntos
Canal Inguinal/patologia , Músculo Liso/enzimologia , ATPases Transportadoras de Cálcio da Membrana Plasmática/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Pré-Escolar , Criptorquidismo/enzimologia , Feminino , Hérnia Inguinal/enzimologia , Humanos , Masculino , Hidrocele Testicular/enzimologia
19.
Asian J Androl ; 8(3): 265-72, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16625275

RESUMO

AIM: To assess the spatiotemporal changes in the expression of extracellular signal-regulated kinases 1 and 2 (ERK1/2), c-Jun N-terminal kinases (JNK) and p38 mitogen-activated protein kinases (MAPK) in response to heat stress in the cryptorchid testis, and to investigate a possible relation to Sertoli cell dedifferentiation. METHODS: Immunohistochemistry and western blot were used to examine the expression and activation of ERK1/2, p38 and JNK in the cryptorchid testis at various stages after experimental cryptorchidism. RESULTS: The abdominal temperature did not obviously change the total ERK1/2 expression but significantly activated phospho-ERK1/2 in the Sertoli cells of the cryptorchid testis. Heat stress increased total JNK expression in the Sertoli cells of the cryptorchid testis but did not activate phospho-JNK. Neither total p38 nor phospho-p38 was induced by heat stress in the Sertoli cells of the cryptorchid testis. Changes in the spatiotemporal expression of cytokeratin 18 (CK18), a marker of immature or undifferentiated Sertoli cells, were induced in the cryptorchid testis in a pattern similar to the activation of ERK1/2. CONCLUSION: The activation of ERK1/2 in the testis may be related to dedifferentiation of Sertoli cells under heat stress induced by experimental cryptorchidism.


Assuntos
Criptorquidismo/enzimologia , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Animais , Criptorquidismo/patologia , Modelos Animais de Doenças , Ativação Enzimática , Imuno-Histoquímica , MAP Quinase Quinase 4/metabolismo , Macaca mulatta , Masculino , Escroto/enzimologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
20.
Free Radic Res ; 39(7): 697-705, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16036348

RESUMO

For normal spermatogenesis, the temperature of the scrotum is lower than that of the body. The mechanism by which mammalian testes undergoes cell death as the result of exposure to heat continues to be a matter of debate. Since generation of reactive oxygen species (ROS) during heat stress and involvement in spermatogenic cell damage are postulated, we induced experimental cryptorchidism in the testes of SOD1-knockout mice and examined effects of the gene deficiency. The cleavage of DNA in testicular cells, as judged by TUNEL staining, were elevated in SOD1-knockout mice at an earlier stage than in the wild-type mice. To confirm responsiveness of SOD1 for this high susceptibility to heat stress, spermatogenic cells were isolated from SOD1-knockout and wild-type mice and cultured at 32.5 and 37 degrees C. The cells isolated from SOD1-knockout were more vulnerable at both temperatures than those from wild-type mice. The exposure of cultured rat spermatogenic cells to ROS induced the release of cytochrome c from mitochondria, while Sertoli cells were more resistant under the same conditions. Tiron, a superoxide scavenger, suppressed the heat-induced release of cytochrome c from mitochondria. Collectively, these data suggest that ROS are generated during heat stress and cause spermatogenic cell death. Alternatively, since even a short exposure triggers harmful damage to spermatogenic cells, generated ROS may function as a type of signal for cell death rather than directly causing oxidative damage to cells.


Assuntos
Criptorquidismo/patologia , Resposta ao Choque Térmico/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Espermatogênese/fisiologia , Superóxido Dismutase/deficiência , Sal Dissódico do Ácido 1,2-Di-Hidroxibenzeno-3,5 Dissulfônico , Animais , Apoptose/efeitos dos fármacos , Criptorquidismo/enzimologia , Criptorquidismo/metabolismo , Citocromos c/metabolismo , Temperatura Alta , Masculino , Camundongos , Camundongos Knockout , Ratos , Ratos Wistar , Células de Sertoli/metabolismo , Células de Sertoli/patologia , Espermatócitos/citologia , Espermatócitos/metabolismo , Espermatócitos/patologia , Superóxido Dismutase/biossíntese , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Superóxido Dismutase-1 , Superóxidos/metabolismo , Testículo/citologia , Testículo/metabolismo , Testículo/patologia
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