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101.
Transforming growth factor beta 1 inhibits gonadotropin action in cultured porcine Sertoli cells. 总被引:3,自引:0,他引:3
A M Morera G Esposito C Ghiglieri M A Chauvin D J Hartmann M Benahmed 《Endocrinology》1992,130(2):831-836
In the present study, we have tested the effects of transforming growth factor beta 1 (TGF beta 1) on FSH action toward aromatase activity and lactate production in cultured Sertoli cells isolated from immature porcine testes. Whereas treatment of Sertoli cells with FSH resulted in a dose-dependent increase (about 7-fold) in aromatase activity (conversion of testosterone into estradiol) (ED50 = 80 ng/ml FSH), the addition of TGF beta 1 reduced this gonadotropin action. The inhibitory effect of TGF beta 1 on FSH aromatase activity was dose dependent (ED50 = 0.1 ng/ml, 4 pM TGF beta 1) with a maximal decrease (about 40%) observed after a long term (48-h) treatment. TGF beta 1 exerted its inhibitory effect on FSH action at the level(s) of cAMP accumulation, exerting no apparent effect on the gonadotropin receptor or at a site(s) related to cAMP action. TGF beta 1 (2 ng/ml) significantly (P less than 0.002) reduced (52% decrease) FSH-stimulated cAMP levels in cultured porcine Sertoli cells. However, such an inhibitory effect of the growth factor was no longer observed when stimulation of cAMP accumulation with FSH occurred in the presence of methyl isobutyl xanthine (0.5 mM), an inhibitor of cAMP-phosphodiesterase activity. This observation suggests that TGF beta 1 decreased cAMP levels by increasing catabolism of the cyclic nucleotide through an enhancement of cAMP-phosphodiesterase activity. The inhibitory effect of TGF beta 1 was not limited to the action of FSH on aromatase activity but also extended to the gonadotropin action (mediated by cAMP) on lactate production. As for the inhibitory effect of TGF beta 1 on FSH-induced aromatase activity, the inhibitory effect of the growth factor on FSH-stimulated lactate production was dose and time dependent with a maximal decrease (about 30%) observed in the picomolar range (1 ng/ml, 40 pM) after 48 h treatment with TGF beta 1. In conclusion, the present study demonstrates that TGF beta 1 attenuates FSH action on Sertoli cell activity and that such inhibitory action is potentially exerted through a decrease in cAMP levels. Because of the local production of TGF beta 1, it is suggested that the effects of the growth factor reported here might be exerted in the context of the testicular paracrine mechanisms. 相似文献
102.
Shiva K. Annamalai Michele L. Esposito Lena Jorde Theodore Schreiber Shelley A. Hall William W. ONeill Navin K. Kapur 《Journal of cardiac failure》2018,24(10):706-710
Background
Myocarditis complicated by cardiogenic shock remains a complex problem. The use of acute mechanical circulatory support devices for cardiogenic shock is growing. We explored the utility of Impella transvalvular microaxial flow catheters in the setting of myocarditis with cardiogenic shock.Methods and Results
We retrospectively analyzed data from 21 sites within the cVAD registry, an ongoing multicenter voluntary registry at sites in North America and Europe that have used Impella in patients with myocarditis. Myocarditis was defined by endomyocardial biopsy (n?=?11) or by clinical history without angiographic evidence of coronary disease (n?=?23). A total of 34 patients received an Impella 2.5, CP, 5.0, or RP device for cardiogenic shock complicating myocarditis. Baseline characteristics included age 42 ± 17 years, left ventricular ejection fraction (LVEF) 18% ± 10%, cardiac index 1.82 ± 0.46 L·min?1·m?2, pulmonary capillary wedge pressure 25 ± 7 mm Hg, and lactate 27 ± 31 mg/dL. Before Impella placement, 32% (n?=?11) of patients required intra-aortic balloon pump. Mean duration of Impella support was 91 ± 74 hours; 21 of 34 patients (62%) survived the index hospitalization and were discharged with an improved mean LVEF of 37.32% ± 20.31% (P?=?.001); 15 patients recovered with successful support, 5 patients were transferred to another hospital on initial Impella support, 1 patient underwent orthotopic heart transplantation. Ten patients required transition to another mechanical circulatory support device.Conclusions
This is the largest analysis of Impella-supported myocarditis cases to date. The use of Impella appears to be safe and effective in the settings of myocarditis complicated by cardiogenic shock. 相似文献103.
104.
Cdric Farges Olivier Cointault Marlne Murris Laurence Lavayssiere Shrazade Lakhdar‐Ghazal Arnaud Del Bello Anne‐Laure Hebral Laure Esposito Marie‐Batrice Nogier Federico Sallusto Xavier Iriart Elena Charpentier Joelle Guitard Fabrice Muscari Camille Dambrin Lydie Porte Nassim Kamar Sophie Cassaing Stanislas Faguer 《Transplant infectious disease》2020,22(1)
105.
Anna Esposito Eliana De Gregorio Maria De Fenza Daniele D'Alonzo Anil Satawani Annalisa Guaragna 《RSC advances》2019,9(37):21519
The synthesis of deflazacort (DFZ) and a preliminary evaluation of its microbial activity against the human pathogens Acinetobacter baumannii and Staphylococcus aureus is herein reported. While DFZ is inactive, one of its synthetic precursors showed a strong antibacterial activity against both Gram-negative and -positive bacteria.Synthesis of deflazacort: unexpected antibacterial activity of its epoxide synthetic precursor. 相似文献
106.
107.
Stross L Günther J Gasteiger G Asen T Graf S Aichler M Esposito I Busch DH Knolle P Sparwasser T Protzer U 《Hepatology (Baltimore, Md.)》2012,56(3):873-883
The strength of antiviral T cell responses correlates with clearance of hepatitis B virus (HBV) infection, but the immunological mechanisms mitigating or suppressing HBV-specific T cells are still poorly understood. In this study, we examined the role of CD4(+) Foxp3(+) regulatory T cells (Tregs) in a mouse model of acute HBV infection. We initiated HBV infection via an adenoviral vector transferring a 1.3-fold overlength HBV genome (AdHBV) into transgenic DEREG mice, where Tregs can be transiently but selectively depleted by injection of diphtheria toxin. The effect of Treg depletion on the outcome of HBV infection was characterized by detailed virological, immunological, and histopathological analysis. Numbers of Tregs increase in the liver rapidly after initiation of HBV replication. Initial depletion of Tregs revealed their complex regulatory function during acute infection. Tregs mitigated immunomediated liver damage by down-regulating the antiviral activity of effector T cells by limiting cytokine production and cytotoxicity, but did not influence development of HBV-specific CD8 T cells or development of memory T cells. Furthermore, Tregs controlled the recruitment of innate immune cells such as macrophages and dendritic cells to the infected liver. As a consequence, Tregs significantly delayed clearance of HBV from blood and infected hepatocytes. Conclusion: Tregs limit immunomediated liver damage early after an acute infection of the liver, thereby contributing to conservation of tissue integrity and organ function at the cost of prolonging virus clearance. (HEPATOLOGY 2012;56:873-883). 相似文献
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