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排序方式: 共有680条查询结果,搜索用时 15 毫秒
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Mariona Guitart‐Mampel Diana L. Juarez‐Flores Lina Youssef Constanza Moren Laura Garcia‐Otero Vicente Roca‐Agujetas Marc Catalan‐Garcia Ingrid Gonzalez‐Casacuberta Ester Tobias Jos C. Milisenda Josep M. Grau Ftima Crispi Eduard Gratacos Francesc Cardellach Glria Garrabou 《Journal of cellular and molecular medicine》2019,23(6):3962-3973
Intrauterine growth restriction (IUGR) is an obstetric complication characterised by placental insufficiency and secondary cardiovascular remodelling that can lead to cardiomyopathy in adulthood. Despite its aetiology and potential therapeutics are poorly understood, bioenergetic deficits have been demonstrated in adverse foetal and cardiac development. We aimed to evaluate the role of mitochondria in human pregnancies with IUGR. In a single‐site, cross‐sectional and observational study, we included placenta and maternal peripheral and neonatal cord blood mononuclear cells (PBMC and CBMC) from 14 IUGR and 22 control pregnancies. The following mitochondrial measurements were assessed: enzymatic activities of mitochondrial respiratory chain (MRC) complexes I, II, IV, I + III and II + III, oxygen consumption (cell and complex I‐stimulated respiration), mitochondrial content (citrate synthase [CS] activity and mitochondrial DNA copy number), total ATP levels and lipid peroxidation. Sirtuin3 expression was evaluated as a potential regulator of bioenergetic imbalance. Intrauterine growth restriction placental tissue showed a significant decrease of MRC CI enzymatic activity (P < 0.05) and CI‐stimulated oxygen consumption (P < 0.05) accompanied by a significant increase of Sirtuin3/β‐actin protein levels (P < 0.05). Maternal PBMC and neonatal CBMC from IUGR patients presented a not significant decrease in oxygen consumption (cell and CI‐stimulated respiration) and MRC enzymatic activities (CII and CIV). Moreover, CS activity was significantly reduced in IUGR new‐borns (P < 0.05). Total ATP levels and lipid peroxidation were preserved in all the studied tissues. Altered mitochondrial function of IUGR is especially present at placental and neonatal level, conveying potential targets to modulate obstetric outcome through dietary interventions aimed to regulate Sirtuin3 function. 相似文献
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Ehlinger Claire Dartevelle Pauline Zaet Abdurraouf Kurashige Yoshihito Haïkel Youssef Metz-Boutigue Marie-Hélène Marban Céline 《International journal of peptide research and therapeutics》2019,25(4):1679-1687
International Journal of Peptide Research and Therapeutics - The success of endodontic treatments depends on the elimination of intracanal pathogens. Since irrigation and instrumentation can only... 相似文献
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Ettamimi Sara Carlier Jorge D. Cox Cymon J. Elamine Youssef Hammani Khalil Ghazal Hassan Costa Maria C. 《Extremophiles : life under extreme conditions》2019,23(6):821-834
Extremophiles - The prokaryotic communities of water bodies contaminated by acid mine drainage from the São Domingos mining area in southern Portugal were analyzed using a meta-taxonomics... 相似文献
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Activation of acid sphingomyelinase by protein kinase Cdelta-mediated phosphorylation 总被引:2,自引:0,他引:2
Although important for cellular stress signaling pathways, the molecular mechanisms of acid sphingomyelinase (ASMase) activation remain poorly understood. Previous studies showed that treatment of MCF-7 mammary carcinoma cells with the potent protein kinase C (PKC) agonist, phorbol 12-myristate 13-acetate (PMA), induces a transient drop in sphingomyelin concomitant with an increase in cellular ceramide levels (Becker, K. P., Kitatani, K., Idkowiak-Baldys, J., Bielawski, J., and Hannun, Y. A. (2005) J. Biol. Chem. 280, 2606-2612). Here we show that PMA selectively activates ASMase and that ASMase accounts for the majority of PMA-induced ceramide. Pharmacologic inhibition and RNA interference experiments indicated that the novel PKC, PKCdelta, is required for ASMase activation. Immunoprecipitation experiments revealed the formation of a novel PKCdelta-ASMase complex after PMA stimulation, and PKCdelta was able to phosphorylate ASMase in vitro and in cells. Using site-directed mutagenesis, we identify serine 508 as the key residue phosphorylated in response to PMA. Phosphorylation of Ser(508) proved to be an indispensable step for ASMase activation and membrane translocation in response to PMA. The relevance of the proposed mechanism of ASMase regulation is further validated in a model of UV radiation. UV radiation also induced phosphorylation of ASMase at serine 508. Moreover, when transiently overexpressed, ASMase(S508A) blocked the ceramide formation after PMA treatment, suggesting a dominant negative function for this mutant. Taken together, these results establish a novel direct biochemical mechanism for ASMase activation in which PKCdelta serves as a key upstream kinase. 相似文献
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Ben Bacha A Gargouri Y Bezzine S Mosbah H Mejdoub H 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,857(1):108-114
Ostrich pancreatic phospholipase A(2) (OPLA(2)) was purified from delipidated pancreases. Pure protein was obtained after heat treatment (70 degrees C), precipitation by ammonium sulphate and ethanol, respectively followed by sequential column chromatography on MonoQ Sepharose and size exclusion HPLC column. Purified OPLA(2), which is not a glycosylated protein, was found to be monomeric protein with a molecular mass of 13773.93 Da. A specific activity of 840U/mg for purified OPLA(2) was measured at optimal conditions (pH 8.2 and 37 degrees C) in the presence of 4 mM NaTDC and 10 mM CaCl(2) using PC as substrate. This enzyme was also found to be able to hydrolyze, at low surface pressure, 1,2-dilauroyl-sn-glycero-3 phosphocholine (di C(12)-PC) monolayers. Maximal activity was measured at 5-8 mNm(-1). The sequence of the first 22 amino-acid residues at the N-terminal extremity of purified bird PLA(2) was determined by automatic Edman degradation and showed a high sequence homology with known mammal pancreatic secreted phospholipases A(2). 相似文献
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Nagy A. Youssef 《The Yale journal of biology and medicine》2022,95(1):171
Psychological trauma is unique in that it is an environmental event that could induce biological changes and post-traumatic stress disorder (PTSD), depression, or other mood disorders in some patients. On the other hand, there may be no psychopathology (in most cases), or even sometimes post-traumatic growth and resilience. According to the DSM-5, trauma is a prerequisite for PTSD and traumatic stress disorder, but not for depressive episodes or mood disorders, or other psychiatric conditions. This paper brings attention to the preliminary literature on transgenerational inheritance due to trauma exposure and its societal and cultural implications. There is accumulating evidence that exposure to trauma can be passed transgenerationally through epigenetic inheritance leading to changes in gene expression and possible disorders or resilience. The effects of resilience from transgenerational inheritance have not been studied, but should be, for a full understanding not only of the disease risk across generations, but also of its social and cultural implications. The epigenetic pathologic effects across generations also need further studies, as the current research is preliminary; larger replications are needed for definitive and more complete understanding. I present here a glimpse of where we are, a vision of where we should go in terms of future research direction for disease risk transmission, and recommend studies of resilience and post-traumatic growth across generations, as well as other studies related to the societal implications at the population level. 相似文献