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Article dans une revue
Differential influence of tacrolimus and sirolimus on mitochondrial-dependent signaling for apoptosis in pancreatic cells
Abstract : To examine and compare the mitochondria-related cellular mechanisms by which tacrolimus (TAC) or sirolimus (SIR) immunosuppressive drugs alter the pancreatic exocrine and endocrine beta-cell fate. Human exocrine PANC-1 and rat endocrine insulin-secreting RIN-m5F cells and isolated rat islets were submitted to 1-100 nM TAC or SIR. In cultures, insulin secretion was measured as endocrine cell function marker. Apoptosis was quantified by annexin 5 and propidium iodide staining. Cleaved caspase-3, Bax apoptosis indicators, and p53, p21 cell cycle regulators were detected by Western blot. Cell cycle and mitochondrial membrane potential (Delta Im) were analyzed by flow cytometry and SA-beta-galactosidase (SA-beta-gal) activity by fluorescence microscopy. Only TAC reduced insulin secretion by RIN-m5F after 24 h. TAC and SIR promoted moderate apoptosis in both PANC-1 and RIN-m5F after 24 h. Apoptosis was associated with up-regulated Bax (threefold) and cleaved caspase-3 (fivefold) but only in PANC-1, while p53 and p21 were up-regulated (twofold) in both cell lines. Delta Im was impaired only in PANC-1 by TAC and SIR. Only SIR prompted cell cycle arrest in both cell lines. The induction of a premature senescence-like phenotype was confirmed in isolated islets by SA-beta-gal activity. TAC and SIR are early inducers of pancreatic cell dysfunction and apoptosis but differentially alter endocrine and exocrine cells via mitochondrial-driven pathways. In rat islets, TAC and SIR prompt a senescence-like phenotype.
https://hal-univ-bourgogne.archives-ouvertes.fr/hal-01430997
Contributeur : Lnc - Université de Bourgogne <>
Soumis le : mardi 10 janvier 2017 - 14:48:39
Dernière modification le : mercredi 14 octobre 2020 - 03:45:38
Contributeur : Lnc - Université de Bourgogne <>
Soumis le : mardi 10 janvier 2017 - 14:48:39
Dernière modification le : mercredi 14 octobre 2020 - 03:45:38