Developmental programming: impact of prenatal testosterone excess on ovarian cell proliferation and apoptotic factors in sheep. Salvetti, NR; Ortega, HH; Veiga-Lopez, A; Padmanabhan, V Biology of reproduction
87
22, 1-10
2011
Mostrar resumen
Prenatal testosterone (T) excess leads to reproductive dysfunctions in sheep, which include increased ovarian follicular recruitment and persistence. To test the hypothesis that follicular disruptions in T sheep stem from changes in the developmental ontogeny of ovarian proliferation and apoptotic factors, pregnant Suffolk sheep were injected twice weekly with T propionate or dihydrotestosterone propionate (DHT; a nonaromatizable androgen) from Days 30 to 90 of gestation. Changes in developmental expression of proliferating cell nuclear antigen (PCNA), BCL2, BAX, activated CASP3, and FAS/FASLG were determined at Fetal Days 90 and 140, 22 wk, 10 mo, and 21 mo of age by immunocytochemisty. Prenatal T treatment induced changes in expression of proliferative and apoptotic markers in a follicle-, age-, and steroid-specific manner. Changes in BAX were evident only during fetal life and PCNA, BCL2, and CASP3 only postnatally. Prenatal T and not DHT increased PCNA and decreased BCL2 in granulosa/theca cells of antral follicles at 10 and 21 mo but decreased CASP3 in granulosa/theca cells of antral follicles at 22 wk (prepubertal) and 10 and 21 mo. Both treatments decreased BAX immunostaining in granulosa cells of Fetal Day 90 primordial/primary follicles. Neither treatment affected FAS expression at any developmental time point in any follicular compartment. Effects on BAX appear to be programmed by androgenic actions and PCNA, BCL2, and CASP3 by estrogenic actions of T. Overall, the findings demonstrate that fetal exposure to excess T disrupts the ovarian proliferation/apoptosis balance, thus providing a basis for the follicular disruptions evidenced in these females. | 22539681
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Force measurements of TCR/pMHC recognition at T cell surface. Puech, PH; Nevoltris, D; Robert, P; Limozin, L; Boyer, C; Bongrand, P PloS one
6
e22344
2010
Mostrar resumen
The rupture forces and adhesion frequencies of single recognition complexes between an affinity selected peptide/MHC complex and a TCR at a murine hybridoma surface were measured using Atomic Force Microscopy. When the CD8 coreceptor is absent, the adhesion frequency depends on the nature of the peptide but the rupture force does not. When CD8 is present, no effect of the nature of the peptide is observed. CD8 is proposed to act as a time and distance lock, enabling the shorter TCR molecule to bridge the pMHC and have time to finely read the peptide. Ultimately, such experiments could help the dissection of the sequential steps by which the TCR reads the peptide/MHC complex in order to control T cell activation. Artículo Texto completo | 21799834
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Cell proliferation and survival mechanisms underlying the abnormal persistence of follicular cysts in bovines with cystic ovarian disease induced by ACTH. Natalia R Salvetti,Matías L Stangaferro,Martín M Palomar,Natalia S Alfaro,Florencia Rey,Eduardo J Gimeno,Hugo H Ortega Animal reproduction science
122
2009
Mostrar resumen
Cystic ovarian disease (COD) is an important cause of infertility that affects cattle. Alterations in the ovarian micro-environment of females with follicular cysts could alter the normal processes of proliferation and programmed cell death in ovarian cells. Thus, the objective in the present study was to evaluate apoptosis and proliferation in induced ovarian cystic follicles in cows to investigate the follicular persistence. Stage of estrous cycle was synchronized in 10 heifers and 5 were then subjected to the induction of COD by administration of ACTH. After the ovariectomy number of in situ apoptotic cells by TUNEL assay, active caspase-3, FAS/FASLG and members of the BCL2 family were compared by immunohistochemistry and multiplex PCR and cell proliferation by evaluation of Ki-67 protein and cyclin D1 and E mRNA. Significantly (p<0.05) lesser proliferative and apoptotic rates were found in cystic follicles from cows with COD compared with those with regular cycles. The relatively minimal proliferation found by immunohistochemistry with Ki-67 marker were confirmed by the gene expression of cyclin D1 and E. Lesser apoptotic rates were associated with decreased amounts of apoptotic-related proteins BAX, FASLG and caspase-3 as well as the in situ apoptosis detected by TUNEL assay, and increased amounts of the anti-apoptotic survival factor cellular BCL2 in the cystic follicles of the COD group. The BAX/BCL2 gene expression profile confirmed the immunohistochemical findings. Results from the present study indicate that cellular proliferation and apoptosis are altered in cystic follicles of cattle. The present study provides new insights into the molecular mechanisms underlying the aberrant persistence of follicular cysts and related diseases. | 20800980
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An imbalance between apoptosis and proliferation contributes to follicular persistence in polycystic ovaries in rats. Salvetti, NR; Panzani, CG; Gimeno, EJ; Neme, LG; Alfaro, NS; Ortega, HH Reproductive biology and endocrinology : RB&E
7
68
2009
Mostrar resumen
Cystic ovarian disease is an important cause of infertility that affects bovine, ovine, caprine and porcine species and even human beings. Alterations in the ovarian micro-environment of females with follicular cysts could alter the normal processes of proliferation and programmed cell death in ovarian cells. Thus, our objective was to evaluate apoptosis and proliferation in ovarian cystic follicles in rats in order to investigate the cause of cystic follicle formation and persistence.We compared the number of in situ apoptotic cells by TUNEL assay, expression of active caspase-3 and members of Bcl-2 family by immunohistochemistry; and cell proliferation by the expression of the proliferation markers: PCNA and Ki-67.The proliferation index was low in granulosa of tertiary and cystic follicles of light exposed rats when compared with tertiary follicles of control animals, while in theca interna only cystic follicles presented low proliferation index when compared with tertiary follicles (p less than 0.05). The granulosa of cysts exhibited a similar cell DNA fragmentation to early atretic follicles. In the granulosa and theca interna, active caspase-3 shown similar immunostaining levels in tertiary and cystic follicles (p less than 0.05). The granulosa cells presented high expression of Bcl-2, Bcl-xL and Bcl-w in the tertiary and cystic follicles with diminishing intensity in the atretic follicles, except with Bcl-w where the intensity was maintained in the atretic follicles (p less than 0.05). The expression of Bax was weak in the healthy and cystic follicles. In the theca interna, Bcl-2 expression was the same as the pattern found in the granulosa; no differences were found between tertiary and cystic follicles from both groups for Bcl-xL and Bcl-w. The expression of Bax in this layer was higher in the tertiary follicles of the treated animals (p less than 0.05) while the values for cystic follicles were similar to those in the tertiary follicles of controls. The theca externa showed low expression of the pro and anti-apoptotic proteins.These results show that the combination of weak proliferation indices and low apoptosis observed in follicular cysts, could explain the cause of the slow growth of cystic follicles and the maintenance of a static condition without degeneration, which leads to their persistence. These alterations may be due to structural and functional modifications that take place in these cells and could be related to hormonal changes in animals with this condition. Artículo Texto completo | 19570211
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Intraovarian localization of growth factors in induced cystic ovaries in rats. H H Ortega, N R Salvetti, P Amable, B E Dallard, C Baravalle, C G Barbeito, E J Gimeno Anatomia, histologia, embryologia
36
94-102
2007
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We hypothesized that the special hormonal environment present in animals with cystic ovarian disease (COD) interferes with cellular production of growth factors (GFs). The objective of the present study was to characterize the expression of insulin-like growth factor (IGF)-I, fibroblast growth factor (FGF)-2 and vascular endothelial growth factor (VEGF) in induced COD using immunohistochemistry. We used an experimental model based on the exposure to constant light of adult rats during 15 weeks. We quantified the expression of GFs in cystic and normal ovaries by the Immunohistochemical Stained Area (IHCSA). In animals with COD, a significant reduction in the IHCSA of IGF-I in the follicular fluid, theca and granulosa layers of cysts occurred; and an increase in the interstitial tissue with regard to the control group. We found moderate immunoreactivity of FGF-2 in granulosa and theca layers of secondary and tertiary follicles and lower expression in the granulosa and theca interna layers of cystic follicles. Immunoexpression of VEGF was found in granulosa and theca cells of secondary and tertiary follicles. This study shows changes in the ovarian expression of IGF-I, FGF-2 and VEGF in induced COD. We can propose that an alteration in the control of the follicular dynamic, through the GFs, added to other features, could be involved in the ovarian cyst pathogenesis. | 17371380
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Effect of a biological response modifier on expression of growth factors and cellular proliferation at drying off. B E Dallard, V Ruffino, S Heffel, L F Calvinho Journal of dairy science
90
2229-40
2007
Mostrar resumen
Agents that increase natural protective mechanisms have been proposed for the prevention and treatment of intramammary infections. Staphylococcus aureus is a major pathogen causing primarily subclinical chronic mastitis that responds poorly to antibiotic therapy. The objectives of this study were to describe the effects of a single intramammary infusion of a lipopolysaccharide-based biological response modifier (BRM) on mammary epithelial cellular proliferation and expression of insulin-like growth factor-I (IGF-I) and vascular endothelial growth factor (VEGF) in uninfected and Staph. aureus-infected bovine mammary glands during involution. Three groups of 12 cows, 6 Staph. aureus-infected and 6 uninfected, were infused with BRM or placebo in 2 mammary quarters and killed at 7, 14, and 21 d of involution. The proportion of infected quarters, mammary cell proliferation, and IGF-I and VEGF expression were evaluated. Biological response modifier treatment decreased the proportion of Staph. aureus-infected mammary quarters at 7 d of involution, but a similar number of isolations were observed at 14 and 21 d of involution in either treated or control quarters. The percentage of proliferating mammary epithelial cells was higher in infected than uninfected quarters at every observation period, irrespective of the treatment administered, whereas uninfected BRM-treated quarters showed increased cell proliferation at 7 d of involution. Insulin-like growth factor-I expression in uninfected quarters was not affected by treatment and showed a decrease at 21 d of involution. Expression of IGF-I was greater in infected than uninfected quarters at every observation period, irrespective of the treatment received. Expression of VEGF was greater in BRM-treated uninfected quarters at 7 d of involution compared with controls. In infected quarters, VEGF expression was lowest in BRM-treated quarters at 7 d of involution and increased throughout the observation period. Conversely, untreated infected quarters showed the highest VEGF expression at 7 d and decreased at 21 d of involution. Mammary cell proliferation and expression of IGF-I and VEGF were increased in Staph. aureus-infected quarters. Increased mammary cell proliferation and VEGF expression were observed in BRM-treated quarters during the first week of involution. | 17430922
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Preventive and therapeutic potential of p38 alpha-selective mitogen-activated protein kinase inhibitor in nonobese diabetic mice with type 1 diabetes. Medicherla, S; Protter, AA; Ma, JY; Mangadu, R; Almirez, R; Koppelman, B; Kerr, I; Navas, TA; Movius, F; Reddy, M; Liu, YW; Luedtke, G; Perumattam, J; Mavunkel, B; Dugar, S; Schreiner, GF The Journal of pharmacology and experimental therapeutics
318
99-107
2005
Mostrar resumen
Mitogen-activated protein kinases (MAPKs) and heat shock proteins (HSPs) are ubiquitous proteins that function within T cells in both normal and stress-related pathophysiological states, including type 1 diabetes. The nonobese diabetic (NOD) mouse spontaneously develops T cell-mediated autoimmune pancreatic beta cell destruction that is similar to type 1 diabetes in humans. Because p38 MAPKs have been shown to modulate T cell function, we studied the effects of a p38alpha MAPK-selective inhibitor, indole-5-carboxamide (SD-169), on the development and progression of type 1 diabetes in the NOD mouse. In preventive treatment studies, SD-169 significantly reduced p38 and HSP60 expression in T cells of the pancreatic beta islets. Following treatment, the incidence of diabetes as determined by blood glucose levels was significantly lower, and immuno-histochemistry of pancreatic beta islet tissue demonstrated significant reduction in CD5+ T cell infiltration in the SD-169 treatment group as compared with untreated NOD mice. In therapeutic studies using mildly and moderately hyperglycemic NOD mice, SD-169 treatment lowered blood glucose and improved glucose homeostasis. Furthermore, following cessation of SD-169 treatment, NOD mice showed significant arrest of diabetes. In conclusion, we report that this p38alpha-selective inhibitor prevents the development and progression of diabetes in NOD mice by inhibiting T cell infiltration and activation, thereby preserving beta cell mass via inhibition of the p38 MAPK signaling pathway. These results have bearing on current prophylactic and therapeutic protocols using p38alpha-selective inhibitors in the prediabetic period for children at high risk of type 1 diabetes, in the honeymoon period, and for adults with latent autoimmune diabetes. | 16603672
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Selective inhibition of p38alpha MAPK improves cardiac function and reduces myocardial apoptosis in rat model of myocardial injury. Li, Z; Ma, JY; Kerr, I; Chakravarty, S; Dugar, S; Schreiner, G; Protter, AA American journal of physiology. Heart and circulatory physiology
291
H1972-7
2005
Mostrar resumen
p38 MAPK is activated during heart diseases that might associate with myocardial damage and deterioration of cardiac function. In a rat model of myocardial injury, we have investigated cardioprotective effects of the inhibition of p38 MAPK using a novel, orally available p38alpha MAPK inhibitor. Rats were treated with N(omega)-nitro-l-arginine methyl ester (l-NAME, 40 mg.kg(-1).day(-1)) in drinking water plus 1% salt for 14 days and ANG II (0.5 mg.kg(-1).day(-1)) for 3 days. A selective p38alpha MAPK inhibitor, SD-282 (60 mg/kg), was administrated orally, twice a day for 4 days, starting 1 day before ANG II administration. The cardioprotective effects of p38alpha MAPK inhibition were evaluated by improvement of cardiac function, reduction of inflammatory cell infiltration, and cardiomyocyte apoptosis. SD-282 significantly improved cardiac function indicated by increasing stroke volume, cardiac output, ejection fraction, and stroke work and significantly decreasing arterial elastance. SD-282 also significantly reduced macrophage infiltration as judged by reduction of a specific marker, ED-1-positive staining cells (P less than 0.05) in the myocardium. Furthermore, cardiomyocyte apoptosis as indicated by caspase-3 immunohistochemical staining was abolished by SD-282, and this effect may contribute to the reduction of myocardial damage evaluated by imaging analysis (P less than 0.05 in both cases). Data suggest that p38alpha MAPK may play a critical role in the pathogenesis of cardiac dysfunction. Inhibition of p38alpha MAPK may be used as a novel cardioprotective strategy in attenuation of inflammatory response and deterioration of cardiac function that occurs in acute cardiovascular disease such as myocardial infarction. | 16751295
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Suppression of arthritis by forced expression of cyclin-dependent kinase inhibitor p21(Cip1) gene into the joints. Y Nonomura, H Kohsaka, K Nasu, Y Terada, M Ikeda, N Miyasaka International immunology
13
723-31
2001
Mostrar resumen
Rheumatoid synovial fibroblasts (RSF) express cyclin-dependent kinase (CDK) inhibitors p16(INK4a) and p21(Cip1) when they are growth-inhibited in vitro. The induction of p16(INK4a) is characteristic of RSF and intra-articular p16(INK4a) gene therapy has been shown to suppress adjuvant arthritis (AA) of rats. The other inducible CDK inhibitor, p21(Cip1), has multiple functions depending on the cell type. They include inhibition of CDK as well as promotion of active CDK complex formation and induction of apoptosis. This study is to discern the biological effects of p21(Cip1) gene transfer into RSF and its therapeutic effects on AA. A recombinant adenovirus containing a human p21(Cip1) gene and control adenoviruses were prepared. RSF infected with these viruses were examined for their cell growth. Apoptotic cell death was evaluated by nuclear staining and DNA fragmentation analysis. In vivo gene therapy of rat AA was carried out by intra-articular injection of the viruses. Severity of the arthritis was clinically scored. The treated joints were examined histologically and proliferating cell nuclear antigens (PCNA) were detected immunohistochemically. The adenoviral p21(Cip1) gene transfer inhibited growth of RSF without inducing apoptosis. p21(Cip1) gene therapy suppressed AA clinically and histologically. The effects were comparable to p16(INK4a) gene therapy. PCNA expression was reduced in the p21(Cip1)-treated joints. The adenoviral gene transfer of p21(Cip1) ameliorated rat AA. The effect was attributable to inhibition of proliferation. Because p21(Cip1) is induced more easily by many chemicals than p16(INK4a), it also appears to be a feasible target in developing anti-rheumatic drugs. | 11369699
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