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1.
Am J Physiol Renal Physiol ; 324(1): F124-F134, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36417276

RESUMO

Although mesangial cell-glomerular basement membrane (GBM) connections play a key role in maintaining the glomerular capillary loop structure, information remains limited about how these connections are formed during glomerulogenesis. We have previously shown that weakened podocyte-GBM interactions owing to tensin 2 (Tns2) deficiency lead to abnormal GBM maturation during postnatal glomerulogenesis. Here, we investigated whether abnormal GBM maturation affected mesangial cell-GBM connections and mesangial cell differentiation. Histological analysis of the outer cortical glomeruli in Tns2-deficient mice revealed that GBM materials overproduced by stressed immature podocytes accumulated in the mesangium and interrupted the formation of mesangial cell-GBM connections, resulting in fewer capillary loops compared with that of normal glomeruli. In addition, expression of α-smooth muscle actin, an immature mesangial cell marker, persisted in mesangial cells of Tns2-deficient outer cortical glomeruli even after glomerulogenesis was completed, resulting in mesangial expansion. Furthermore, analysis of mouse primary mesangial cells revealed that mesangial cell differentiation depended on the type of extracellular matrix components to which the cells adhered, suggesting the participation of mesangial cell-GBM connections in mesangial cell differentiation. These findings suggest that abnormal GBM maturation affects mesangial cell differentiation by impairing mesangial cell-GBM connections.NEW & NOTEWORTHY Mesangial cell-glomerular basement membrane (GBM) connections play an important role in maintaining the structural integrity of the glomerular tuft. However, information remains scarce about how GBM maturation affects the formation of these connections during glomerular development. Here, we show that abnormal GBM maturation due to tensin 2 deficiency affects mesangial cell differentiation by impairing mesangial cell-GBM connections during postnatal glomerulogenesis.


Assuntos
Membrana Basal Glomerular , Podócitos , Camundongos , Animais , Membrana Basal/metabolismo , Tensinas , Mesângio Glomerular , Podócitos/metabolismo , Diferenciação Celular
2.
Am J Physiol Renal Physiol ; 318(6): F1520-F1530, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32390516

RESUMO

Tensin2 (Tns2), an integrin-linked protein, is enriched in podocytes within the glomerulus. Previous studies have revealed that Tns2-deficient mice exhibit defects of the glomerular basement membrane (GBM) soon after birth in a strain-dependent manner. However, the mechanisms for the onset of defects caused by Tns2 deficiency remains unidentified. Here, we aimed to determine the role of Tns2 using newborn Tns2-deficient mice and murine primary podocytes. Ultrastructural analysis revealed that developing glomeruli during postnatal nephrogenesis exhibited abnormal GBM processing due to ectopic laminin-α2 accumulation followed by GBM thickening. In addition, analysis of primary podocytes revealed that Tns2 deficiency led to impaired podocyte-GBM interaction and massive expression of laminin-α2 in podocytes. Our study suggests that weakened podocyte-GBM interaction due to Tns2 deficiency causes increased mechanical stress on podocytes by continuous daily filtration after birth, resulting in stressed podocytes ectopically producing laminin-α2, which interrupts GBM processing. We conclude that Tns2 plays important roles in the podocyte-GBM interaction and maintenance of the glomerular filtration barrier.


Assuntos
Membrana Basal Glomerular/metabolismo , Taxa de Filtração Glomerular , Podócitos/metabolismo , Tensinas/metabolismo , Fatores Etários , Animais , Animais Recém-Nascidos , Adesão Celular , Células Cultivadas , Membrana Basal Glomerular/ultraestrutura , Laminina/genética , Laminina/metabolismo , Camundongos Knockout , Podócitos/ultraestrutura , Estresse Mecânico , Tensinas/deficiência , Tensinas/genética
3.
J Reprod Dev ; 66(1): 29-33, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-31801913

RESUMO

In female mammals, luteal cells rapidly proliferate and form corpora lutea (CLs) after ovulation. The corpus luteum (CL) plays crucial roles in establishing and maintaining pregnancy. To gain further insights into the role of cellular FLICE-like inhibitory protein (cFLIP), an anti-apoptosis factor that is structurally similar to procaspase-8 but lacks proteolytic enzyme activity, we examined the expression in CLs of Thai swamp buffalos (Bubalus bubalis) during the early, mid, and late stage of the estrous cycle and pregnancy. cFLIP short form and long form (cFLIPS and cFLIPL, respectively) mRNA and protein levels were assessed by reverse transcription-polymerase chain reaction and western blotting, respectively. cFLIPS mRNA levels were low in the mid and late stages of the estrous cycle and increased during pregnancy (P < 0.05). cFLIPL mRNA was highly expressed in CLs during pregnancy and was lower in the mid and late stages of the estrous cycle. The level of cFLIPS protein was high in CLs during pregnancy and low levels were noted in the mid stage of the estrous cycle (P < 0.05). Higher levels of cFLIPL protein were demonstrated in CLs during pregnancy and lower levels were found in CLs during the early stage of the estrous cycle. Strong positive immunohistochemical staining for cFLIPS/L proteins was observed in luteal cells during pregnancy. The present findings revealed that cFLIP was at the highest level in CLs during pregnancy, and this may act as a dominant survival anti-apoptotic factor by inhibiting intracellular apoptosis signal transduction in luteal cells of CLs during pregnancy.


Assuntos
Búfalos/fisiologia , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/metabolismo , Corpo Lúteo/metabolismo , Ciclo Estral/metabolismo , Animais , Apoptose/fisiologia , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/genética , Ciclo Estral/genética , Feminino , Células Lúteas/metabolismo , Gravidez , Progesterona/sangue
4.
Genes Immun ; 20(2): 121-130, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-29550838

RESUMO

C1s deficiency is strongly associated with the development of human systemic lupus erythematosus (SLE); however, the mechanisms by which C1s deficiency contributes to the development of SLE have not yet been elucidated in detail. Using ICR-derived-glomerulonephritis (ICGN) mouse strain that develops SLE and very weakly expresses C1s in the liver, we investigated the protective roles of C1s against SLE. A genetic sequence analysis revealed complete deletion of the C1s1 gene, a mouse homolog of the human C1s gene, with partial deletion of the C1ra and C1rb genes in the ICGN strain. This deletion led to the absence of C1r/C1s and a low level of C1q in the circulation. In order to investigate whether the C1r/C1s deficiency induces SLE, we produced a congenic mouse strain by introducing the deletion region of ICGN into the C57BL/6 strain. Congenic mice exhibited no C1r/C1s and a low level of C1q in the circulation, but did not have any autoimmune defects. These results suggest that C1r/C1s deficiency is not sufficient to drive murine SLE and also that other predisposing genes exist in ICGN mice.


Assuntos
Complemento C1r/genética , Complemento C1s/genética , Lúpus Eritematoso Sistêmico/genética , Animais , Complemento C1r/deficiência , Complemento C1s/deficiência , Feminino , Deleção de Genes , Camundongos , Camundongos Endogâmicos ICR
5.
J Reprod Dev ; 62(2): 209-12, 2016 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-26875568

RESUMO

The antioxidant effect of N, N-dimethylglycine (DMG) on in vitro-produced (IVP) bovine embryos was examined. After in vitro fertilization, presumptive zygotes were cultured with or without 0.1 µM DMG under different oxygen tensions. The percentage of embryos developing to the blastocyst stage was lowest under a 20% oxygen concentration without DMG, and it was significantly increased (P < 0.05) by applying a 5% oxygen concentration. Under the 20% oxygen concentration, supplementation of the medium with DMG significantly improved blastocyst development, which was nearly equal to that achieved under 5% oxygen without DMG. Furthermore, a tendentious increase (P = 0.06) in blastocyst cell numbers was observed when DMG was applied. In the second experiment, addition of H2O2 (0.5 mM) to the culture medium significantly (P < 0.01) reduced the percentage of embryos developing to the blastocyst stage. However, DMG supplementation prevented this reduction. In conclusion, DMG enhanced the invitro development of IVP bovine embryos by acting as an antioxidant.


Assuntos
Técnicas de Cultura Embrionária/métodos , Estresse Oxidativo , Sarcosina/análogos & derivados , Animais , Antioxidantes/química , Blastocisto/citologia , Bovinos , Meios de Cultura , Desenvolvimento Embrionário/efeitos dos fármacos , Feminino , Fertilização in vitro , Peróxido de Hidrogênio/farmacologia , Masculino , Folículo Ovariano/citologia , Oxigênio/química , Sarcosina/química , Zigoto
6.
J Virol ; 88(22): 13352-66, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25210167

RESUMO

UNLABELLED: Equine hepacivirus (EHcV) has been identified as a closely related homologue of hepatitis C virus (HCV) in the United States, the United Kingdom, and Germany, but not in Asian countries. In this study, we genetically and serologically screened 31 serum samples obtained from Japanese-born domestic horses for EHcV infection and subsequently identified 11 PCR-positive and 7 seropositive serum samples. We determined the full sequence of the EHcV genome, including the 3' untranslated region (UTR), which had previously not been completely revealed. The polyprotein of a Japanese EHcV strain showed approximately 95% homology to those of the reported strains. HCV-like cis-acting RNA elements, including the stem-loop structures of the 3' UTR and kissing-loop interaction were deduced from regions around both UTRs of the EHcV genome. A comparison of the EHcV and HCV core proteins revealed that Ile(190) and Phe(191) of the EHcV core protein could be important for cleavage of the core protein by signal peptide peptidase (SPP) and were replaced with Ala and Leu, respectively, which inhibited intramembrane cleavage of the EHcV core protein. The loss-of-function mutant of SPP abrogated intramembrane cleavage of the EHcV core protein and bound EHcV core protein, suggesting that the EHcV core protein may be cleaved by SPP to become a mature form. The wild-type EHcV core protein, but not the SPP-resistant mutant, was localized on lipid droplets and partially on the lipid raft-like membrane in a manner similar to that of the HCV core protein. These results suggest that EHcV may conserve the genetic and biological properties of HCV. IMPORTANCE: EHcV, which shows the highest amino acid or nucleotide homology to HCV among hepaciviruses, was previously reported to infect horses from Western, but not Asian, countries. We herein report EHcV infection in Japanese-born horses. In this study, HCV-like RNA secondary structures around both UTRs were predicted by determining the whole-genome sequence of EHcV. Our results also suggest that the EHcV core protein is cleaved by SPP to become a mature form and then is localized on lipid droplets and partially on lipid raft-like membranes in a manner similar to that of the HCV core protein. Hence, EHcV was identified as a closely related homologue of HCV based on its genetic structure as well as its biological properties. A clearer understanding of the epidemiology, genetic structure, and infection mechanism of EHcV will assist in elucidating the evolution of hepaciviruses as well as the development of surrogate models for the study of HCV.


Assuntos
Genoma Viral , Hepacivirus/isolamento & purificação , Hepatite C/veterinária , Doenças dos Cavalos/virologia , RNA Viral/genética , Animais , Sequência Conservada , Ordem dos Genes , Hepacivirus/genética , Hepacivirus/imunologia , Hepatite C/virologia , Anticorpos Anti-Hepatite C/sangue , Cavalos , Japão , Dados de Sequência Molecular , RNA Viral/sangue , Análise de Sequência de DNA , Homologia de Sequência
7.
Biochim Biophys Acta ; 1823(10): 1825-40, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22801217

RESUMO

Caspase-8 (CASP8) is a cysteine protease that plays a pivotal role in the extrinsic apoptotic signaling pathway via death receptors. The kinetics, dynamics, and selectivity with which the pathway transmits apoptotic signals to downstream molecules upon CASP8 activation are not fully understood. We have developed a system for using high-sensitivity FRET-based biosensors to monitor the protease activity of CASP8 and its downstream effector, caspase-3, in living single cells. Using this system, we systematically investigated the caspase cascade by regulating the magnitude of extrinsic signals received by the cell. Furthermore, we determined the molar concentration of five caspases and Bid required for hierarchical transmission of apoptotic signals in a HeLa cell. Based on these quantitative experimental data, we validated a mathematical model suitable for estimation of the kinetics and dynamics of caspases, which predicts the minimal concentration of CASP8 required to act as an initiator. Consequently, we found that less than 1% of the total CASP8 proteins are sufficient to set the apoptotic program in motion if activated. Taken together, our findings demonstrate the precise cascade of CASP8-mediated apoptotic signals through the extrinsic pathway.


Assuntos
Apoptose , Caspase 8/metabolismo , Modelos Biológicos , Apoptose/efeitos dos fármacos , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/metabolismo , Técnicas Biossensoriais , Caspase 3/metabolismo , Caspase 6/metabolismo , Inibidores de Caspase , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Retroalimentação Fisiológica/efeitos dos fármacos , Transferência Ressonante de Energia de Fluorescência , Células HeLa , Humanos , Peptídeos/farmacologia , Receptores de Morte Celular/metabolismo , Reprodutibilidade dos Testes , Transdução de Sinais/efeitos dos fármacos
8.
Connect Tissue Res ; 54(6): 416-25, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23972401

RESUMO

Collagen in an eggshell membrane is important for egg preservation, medical burn treatment and manufacturing of cosmetics. Because collagen in the membrane is little, it is a need to improve the accumulation in the membrane to develop these applications. Wood charcoal powder with vinegar (WCV) is a natural substance that improves poultry production. In hen fed with WCV, total collagen in the eggshell membrane increased with an increase in dietary WCV and significantly increased in the 1.0% WCV group (p < 0.05). Scanning and light microscopic images revealed that this group had thicker eggshell membranes and a fine mesh structure composed of finer and more densely distributed fibres than in the control. Eggs from WCV group showed slow Haugh unit decrease during egg storage and the decrease correlated with total collagen in eggshell membrane. In intact chicken, type I and type III collagens were found in different specific locations in the oviduct but not in the membrane. The finding that collagen accumulates in the eggshell membrane under WCV feeding suggests that feeding chicken with WCV will permit long-term storage of eggs in poultry production, and the increased volume of total collagen will facilitate its application in medicine and cosmetics.


Assuntos
Ácido Acético/farmacologia , Carvão Vegetal/farmacologia , Galinhas/metabolismo , Colágeno Tipo III/metabolismo , Colágeno Tipo I/metabolismo , Dieta/veterinária , Casca de Ovo/efeitos dos fármacos , Madeira/química , Animais , Western Blotting , Casca de Ovo/citologia , Casca de Ovo/metabolismo , Casca de Ovo/ultraestrutura , Feminino , Imunofluorescência , Membranas/efeitos dos fármacos , Membranas/metabolismo , Membranas/ultraestrutura , Oviductos/efeitos dos fármacos , Oviductos/metabolismo , Pós
9.
Nephron Exp Nephrol ; 123(3-4): 22-33, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23988887

RESUMO

BACKGROUND/AIMS: Tenc1 (also known as tensin2) is an integrin-associated focal adhesion molecule that is broadly expressed in mouse tissues including the liver, muscle, heart and kidney. A mouse strain carrying mutated Tenc1, the ICR-derived glomerulonephritis (ICGN) strain, develops severe nephrotic syndrome. METHODS: To elucidate the function of Tenc1 in the kidney, Tenc1(ICGN) was introduced into 2 genetic backgrounds, i.e. DBA/2J (D2) and C57BL/6J (B6), strains that are respectively susceptible and resistant to chronic kidney disease. RESULTS: Biochemical and histological analysis revealed that homozygous Tenc1(ICGN) mice develop nephrotic syndrome on the D2 background (D2GN) but not on the B6 background (B6GN). Initially, abnormal assembly and maturation of glomerular basement membrane (GBM) were observed, and subsequently effacement of podocyte foot processes was noted in the kidneys of D2GN but not B6GN mice. These defects are likely to be involved in the integrin signaling pathway. CONCLUSION: This study suggests that Tenc1 contributes to the maintenance of GBM structures and that the genetic background influences the severity of nephrotic syndrome.


Assuntos
Membrana Basal Glomerular/metabolismo , Glomerulonefrite/metabolismo , Glomérulos Renais/metabolismo , Síndrome Nefrótica/metabolismo , Fosfoproteínas Fosfatases/deficiência , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Western Blotting , Colágeno Tipo IV/metabolismo , Proteínas do Citoesqueleto/metabolismo , Membrana Basal Glomerular/patologia , Membrana Basal Glomerular/ultraestrutura , Glomerulonefrite/genética , Glomerulonefrite/patologia , Integrina alfa3beta1/metabolismo , Glomérulos Renais/patologia , Glomérulos Renais/ultraestrutura , Laminina/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Camundongos Endogâmicos ICR , Camundongos Knockout , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência , Síndrome Nefrótica/genética , Síndrome Nefrótica/patologia , Fosfoproteínas Fosfatases/genética , Fosfoproteínas Fosfatases/metabolismo , Podócitos/metabolismo , Podócitos/patologia , Podócitos/ultraestrutura , Proteinúria/urina , Especificidade da Espécie , Tensinas
10.
Nephron Exp Nephrol ; 123(3-4): 34-45, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23989031

RESUMO

BACKGROUND: ICR-derived glomerulonephritis (ICGN) strain is a novel inbred strain of mice with a hereditary nephrotic syndrome. Deletion mutation of tensin 2 (Tns2), a focal adhesion molecule, has been suggested to be responsible for nephrotic syndrome in ICGN mice; however, the existence of other associative factors has been suggested. METHODS AND RESULTS: To identify additional associative factors and to better understand the onset mechanism of nephrotic syndrome in ICGN mice, we conducted a comprehensive gene expression analysis using DNA microarray. Immune-related pathways were markedly altered in ICGN mice kidney as compared with ICR mice. Furthermore, the gene expression level of complement component 1, s subcomponent (C1s), whose human homologue has been reported to associate with lupus nephritis, was markedly low in ICGN mouse kidney. Real-time quantitative reverse transcription-polymerase chain reaction confirmed a low expression level of C1s in ICGN mouse liver where the C1s protein is mainly synthesized. A high serum level of anti-dsDNA antibody and deposits of immune complexes were also detected in ICGN mice by enzyme-linked immunosorbent assay and immunohistochemical analyses, respectively. CONCLUSION: Our results suggest that the immune system, especially the complement system, is associated with nephrotic syndrome in ICGN mice. We identified a low expression level of C1s gene as an additional associative factor for nephrotic syndrome in ICGN mice. Further studies are needed to elucidate the role of the complement system in the onset of nephrotic syndrome in ICGN mice.


Assuntos
Complemento C1s/genética , Glomerulonefrite/genética , Síndrome Nefrótica/genética , Transcriptoma , Animais , Anticorpos Antinucleares/sangue , Anticorpos Antinucleares/imunologia , Complemento C1s/metabolismo , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Glomerulonefrite/sangue , Glomerulonefrite/imunologia , Humanos , Imuno-Histoquímica , Rim/metabolismo , Rim/patologia , Nefrite Lúpica/genética , Camundongos , Camundongos Endogâmicos ICR , Síndrome Nefrótica/sangue , Síndrome Nefrótica/imunologia , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
11.
Reprod Fertil Dev ; 25(4): 589-99, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22954232

RESUMO

High lipid content in embryos is associated with low freezing tolerance. This study assessed the effects of exogenous L-carnitine, an enhancer of lipid metabolism, on the in vitro development and freezing survival of bovine embryos. Also, effects on metabolic activity, reactive oxygen species (ROS) and apoptosis were investigated. Supplementation of embryo culture medium with 1.518 mM or 3.030 mM L-carnitine significantly increased the rates of zygote development to the blastocyst stage and blastocyst cell numbers whereas 6.072 mM of this compound did not improve embryo development. Survival rates after slow freezing of blastocysts were significantly higher when embryos were cultured in the presence of 1.518 mM or 3.030 mM L-carnitine compared with the control. A lower density of lipid droplets was detected in L-carnitine-treated blastocysts compared with the control. L-carnitine significantly reduced ROS levels in 2-cell embryos but did not reduce ROS levels at later stages. The apoptotic cell rate was not different between control and L-carnitine-treated blastocysts. L-carnitine significantly increased ATP levels in 2-cell embryos but not at the 8-cell or blastocyst stages. L-carnitine increased the expression of metabolism-related ATP6 and COX1 genes in blastocysts. In conclusion, L-carnitine supplementation enhanced lipid metabolism in embryos resulting in improved development and cryotolerance of bovine blastocysts produced in vitro.


Assuntos
Aclimatação/efeitos dos fármacos , Carnitina/farmacologia , Meios de Cultura/química , Embrião de Mamíferos/fisiologia , Desenvolvimento Embrionário/efeitos dos fármacos , Congelamento , Trifosfato de Adenosina/metabolismo , Animais , Apoptose/efeitos dos fármacos , Bovinos , Técnicas de Cultura Embrionária/métodos , Embrião de Mamíferos/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
12.
J Reprod Dev ; 59(5): 437-41, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24162808

RESUMO

Worldwide, only a few "fatty" pig breeds exist with different and/or regional utilization. Using the Hungarian Mangalica, which almost went extinct in Europe and the Lao Moo Lat pig, which still has a large population in South-East Asia as exemples, we wanted to demonstrate that indigenous (fatty) pig breeds may represent both national value and tremendous economic potential. Since these less prolific and less productive breeds cannot contribute to mass production, new market roles and methods should be established for them in the premium segment of pork trading. Thus their preservation and propagation needs the comprehensive collaboration of commercial, governmental actors and researchers. Briefly summarizing the history, we report the current results of reproductive physiology research. The commercial renaissance of Mangalica pigs is indebted to the enthusiastic efforts of basic scientists, pig breeding experts and dedicated Mangalica producers. Scientific achievements were applied to practical breeding and production of delicious pork and processed products, which ultimately made the economic success in the Mangalica sector possible. Both, research on and utilization of endangered (pig) breeds maintain not only breed diversities, but also may improve the livelihood of farmers worldwide.


Assuntos
Criação de Animais Domésticos , Dieta , Espécies em Perigo de Extinção , Qualidade dos Alimentos , Carne/análise , Sus scrofa/crescimento & desenvolvimento , Adiposidade , Criação de Animais Domésticos/economia , Animais , Cruzamento , Dieta/etnologia , Espécies em Perigo de Extinção/economia , Feminino , Genética Populacional , Hungria , Inseminação Artificial/veterinária , Laos , Masculino , Carne/economia , Filogeografia , Parcerias Público-Privadas , Sus scrofa/genética
13.
J Reprod Dev ; 59(6): 549-56, 2013 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-23965685

RESUMO

Mitochondria are reported to be critical in in vitro maturation of oocytes and subsequent embryo development after fertilization, but their contribution for fertilization has not been investigated in detail. In the present study, we investigate the contribution of mitochondria to fertilization using reconstructed porcine oocytes by fusion of ooplasmic fragments produced by serial centrifugations (centri-fusion). Firstly, we evaluated the characteristics of ooplasmic fragments. Three types of fragments were obtained by centrifugation of porcine oocytes matured in vitro for 46 h: brownish (B), transparent (T) and large (L) fragments containing both B and T parts in a fragment. The production efficiencies of these types of fragments were 71.7, 91.0 and 17.8 fragments/100 oocytes, respectively. In experiments, L fragments were excluded because they contained both brownish and transparent components that were apparently intermediate between B and T fragments. Observations by confocal microscopy after staining with MitoTracker Red CMXRos® and transmission electron microscopy revealed highly condensed active mitochondria in B fragments in contrast to T fragments that contained only sparse organelles. We reconstructed oocytes by fusion of a karyoplast and two cytoplasts from B and T fragments (B and T oocytes, respectively). The B oocytes showed higher sperm penetration (95.8%) and male pronuclear formation rates (94.2%) by in vitro fertilization than T oocytes (66.7% and 50.0%, respectively). These results suggest that the active mitochondria in oocytes may be related to their ability for fertilization.


Assuntos
Fertilização in vitro , Mitocôndrias/fisiologia , Oócitos/fisiologia , Interações Espermatozoide-Óvulo , Regulação para Cima , Matadouros , Animais , Animais Endogâmicos , Sistema Livre de Células , Centrifugação com Gradiente de Concentração , Cruzamentos Genéticos , Criopreservação , Estruturas Citoplasmáticas/fisiologia , Estruturas Citoplasmáticas/ultraestrutura , Técnicas Eletroquímicas , Feminino , Técnicas de Maturação in Vitro de Oócitos , Japão , Masculino , Fusão de Membrana , Mitocôndrias/ultraestrutura , Oócitos/ultraestrutura , Espermatozoides , Sus scrofa
14.
J Equine Sci ; 24(1): 1-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24833996

RESUMO

The present study aimed to clarify changes of oxidative stress and antioxidative functions in treadmill-exercised Thoroughbred horses (n=5, 3 to 7 years old), using recently developed techniques for measurement of serum d-ROMs for oxidative stress, and BAP for antioxidative markers. Also, the effect of nasogastric administration of hydrogen-rich water (HW) or placebo water preceding the treadmill exercise on these parameters was examined. Each horse was subjected to a maximum level of treadmill exercise in which the horses were exhausted at an average speed of 13.2 ± 0.84 m/sec. Blood samples were taken 4 times, immediately before the intake of HW or placebo water at 30 min preceding the treadmill exercise, immediately before the exercise (pre-exercise), immediately after the exercise (post-exercise) and at 30 min following the exercise. In all horses, both d-ROMs and BAP values significantly increased at post-exercise. The increase in d-ROMs tended to be lower in the HW trial, as compared to the placebo trial at pre-exercise. The increase in BAP was considerable at approximately 150% of the pre-exercise values in both the HW and placebo treatment trials. The BAP/d-ROMs ratio was significantly elevated at post-exercise in both treatment trials, while a significant elevation was also observed at pre-exercise in the HW trial. BAP, d-ROM, and the BAP/d-ROM ratio tended to decline at 30 min after the exercise, except BAP and BAP/d-ROMs in the placebo trial. These results demonstrate that the marked elevation of oxidative stress and anitioxidative functions occurred simultaneously in the intensively exercised horses, and suggest a possibility that HW has some antioxidative efficacy.

15.
J Equine Sci ; 24(3): 31-6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24833999

RESUMO

Genetic polymorphisms in genes related to neurotransmitters or hormones affect personality or behavioral traits in many animal species including humans. In domestic animals, the allele frequency of such genes has been reported to be different among breeds and it may account for breed differences in behavior. In this study, we investigated breed differences in horses in the dopamine receptor D4 gene (DRD4), which has been reported to affect horse personality. We collected samples from seven horse breeds including those native to Japan and Korea, and compared the sequence of the DRD4 exon3 region among these breeds. We found that there were two types of polymorphisms (VNTR and SNPs) in the exon3 region, and some of them seemed to be breed-specific. In addition, we found that the allele frequency of G292A, reported to be associated with horse personality, differed greatly between native Japanese horses and Thoroughbred horses. The frequency of the A allele which is associated with low curiosity and high vigilance, was much lower in native Japanese horses (Hokkaido, 0.03; Taishu, 0.08) than in Thoroughbreds (0.62). This difference may account for breed differences in personality or behavioral traits. Further studies of the function of these polymorphisms and their effect on behavior are indicated.

16.
J Reprod Dev ; 58(1): 44-50, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22450284

RESUMO

The mammalian ovary is an extremely dynamic organ in which a large majority of follicles are effectively eliminated throughout their reproductive life. Due to the numerous efforts of researchers, mechanisms regulating follicular growth and atresia in mammalian ovaries have been clarified, not only their systemic regulation by hormones (gonadotropins) but also their intraovarian regulation by gonadal steroids, growth factors, cytokines and intracellular proteins. Granulosa cells in particular have been demonstrated to play a major role in deciding the fate of follicles, serving molecules that are essential for follicular growth and maintenance as well as killing themselves by an apoptotic process that results in follicular atresia. In this review, we discuss the factors that govern follicular growth and atresia, with a special focus on their regulation by granulosa cells. First, ovarian folliculogenesis in adult life is outlined. Then, we explain about the regulation of follicular growth and atresia by granulosa cells, in which hormones, growth factors and cytokines, death ligand-receptor system and B cell lymphoma/leukemia 2 (BCL2) family members (mitochondria-mediated apoptosis) are further discussed.


Assuntos
Atresia Folicular/fisiologia , Folículo Ovariano/crescimento & desenvolvimento , Animais , Apoptose/fisiologia , Bovinos , Sobrevivência Celular , Feminino , Células da Granulosa/fisiologia , Hormônios/fisiologia , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/fisiologia , Camundongos , Folículo Ovariano/fisiologia , Proteínas Proto-Oncogênicas c-bcl-2/fisiologia , Ratos , Suínos/fisiologia
17.
J Reprod Dev ; 58(1): 112-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22052011

RESUMO

In mitochondrion-dependent type II apoptosis, BH3-interacting domain death agonist (BID) and BCL-2-associated X protein (BAX) promote death ligand and receptor-mediated cell death. In porcine ovaries, the levels of BID and BAX increase in follicular granulosa cells during atresia. In the present study, to confirm the pro-apoptotic activity of BID and BAX in granulosa cells, we examined the effect of RNA interference of BID or BAX on apoptosis using a human ovarian granulosa tumor cell line, KGN. By reverse transcription polymerase chain reaction (RT-PCR) and Western blotting, expression of BID and BAX was detected in KGN cells. Then, we suppressed BID and BAX mRNA expression in KGN cells using small interfering RNA (siRNA). When BID or BAX was suppressed, a significant decrease in the apoptotic cell rate was noted. In granulosa-derived cells, BID and BAX showed pro-apoptotic activity. These results suggest that BID and BAX act as signal-transducing factors in mitochondrion-dependent type II apoptosis.


Assuntos
Apoptose , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/biossíntese , Células da Granulosa/metabolismo , Interferência de RNA , Proteína X Associada a bcl-2/biossíntese , Linhagem Celular Tumoral , Feminino , Humanos , Transdução de Sinais
18.
J Reprod Dev ; 58(1): 61-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21986231

RESUMO

To clarify the effect of lactation period on ovarian follicular activity and associated hormonal levels in goats, six goats were monitored daily by ultrasonographic examination with blood sampling during early (Days 5 to 25; Day 0 was the day of kidding) and late (Days 40 to 60) lactation. While the presence of a corpus luteum of pregnancy retarded follicular growth in the ipsilateral ovary until Days 11-13 postpartum, the total follicular number (TFN) and area (TFA) increased during late lactation due to the significant increase in the number of medium- and large-sized follicles and decrease in the number of small follicles. Four goats showed a similar pattern of follicular development during the period studied characterized by the emergence of five and six waves during the early and late lactation, respectively. The largest follicle diameter of the first three waves monitored during early lactation was significantly smaller as compared with the diameter of those existing during late lactation. TFN showed a positive correlation with FSH but showed a negative correlation with immunoreactive (ir-) inhibin and estradiol during the postpartum period. TFA was positively correlated with ir-inhibin, estradiol and PRL and negatively correlated with FSH during the monitored periods. The plasma levels of ir-inhibin and progesterone were significantly higher during late lactation compared with the levels recorded during early lactation. Ir-inhibin levels showed a significant positive correlation with LH and estradiol during early and late lactation but showed a negative correlation with FSH during the whole lactation period. LH was positively correlated with estradiol and PRL during early and late lactation, respectively. These results suggest that the lactation period has a detrimental effect on ovarian activity during the early postpartum period in goats.


Assuntos
Cabras/fisiologia , Lactação/fisiologia , Folículo Ovariano/fisiologia , Animais , Corpo Lúteo/fisiologia , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Cabras/sangue , Inibinas/sangue , Lactação/sangue , Hormônio Luteinizante/sangue , Progesterona/sangue
19.
J Reprod Dev ; 57(2): 169-75, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21551974

RESUMO

In the mammalian ovary, more than 99% of follicles degenerate without ovulation and few oocytes ovulate and succeed to the next generation. Granulosa cell apoptosis plays a critical role in this process, follicular atresia. However, the molecular mechanisms responsible for the regulation of granulosa cell apoptosis have not been clarified. Death ligand and receptor systems are major apoptosis-inducing factors. This review describes the granulosa cell apoptosis via death ligand and receptor systems during follicular atresia in the porcine ovary.


Assuntos
Apoptose , Células da Granulosa/metabolismo , Receptores do Fator de Necrose Tumoral/metabolismo , Fatores de Necrose Tumoral/metabolismo , Animais , Feminino , Suínos
20.
J Reprod Dev ; 57(3): 335-41, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21289465

RESUMO

The survival rate of vitrified germinal vesicle (GV) stage porcine oocytes is very low, and it is not known if the vitrification damages the nucleus, cytoplasm or both. We have evaluated the eventual GV or cytoplasmic damage in fully grown (FG) and growing vitrified oocytes. Fifty-five percent of nonvitrified FG cumulus-denuded oocytes reached the metaphase II (MII) stage in culture. When growing oocytes from preantral (PA) and early antral (EA) follicles were matured in vitro, almost all oocytes were arrested at the GV stage (GV stage: PA 88.9 and EA 79.5%, respectively). When fresh GVs from FG, PA and EA oocytes were transferred into fresh enucleated FG oocytes and matured in vitro, some of them reached the MII stage (MII stage: FG/FG 57.5%, PA/FG 9.3% and EA/FG 35.3%, respectively). The maturation rate of vitrified FG oocytes was only 6.1% but increased dramatically when vitrified GVs from FG, PA and EA oocytes were transferred into fresh enucleated FG oocytes (MII stage: VitFG/FG 43.9%, VitPA/FG 7.1% and VitEA/FG 26.3%, respectively). These results were not significantly different from those for the nonvitrified groups (MII stage: FG/FG 57.5%, PA/FG 9.3% and EA/FG 35.3%, respectively). We activated the reconstructed oocytes that received fresh or vitrified GVs (FG/FG, EA/FG, VitFG/FG and VitEA/FG) and examined their embryonic development. Cleaved embryos (nonvitrified groups 13.0-61.8%, vitrified groups 33.3-40.0%) and blastocysts (nonvitrified groups 0.0-18.2%, vitrified groups 0.0-2.9%) were obtained after activation. These results demonstrate that vitrified porcine GVs maintain maturational and developmental competence and that vitrification predominantly damages the cytoplasm.


Assuntos
Oócitos , Suínos , Vitrificação , Animais , Blastocisto/efeitos dos fármacos , Células Cultivadas , Crioprotetores/farmacologia , Feminino
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