RESUMO
The Ru(II)-nitrite complex, Ru4, is explored to release nitric oxide (NO) under acidic conditions and selectively induce a cytotoxic effect towards SK-MEL-28 cisplatin-resistant malignant melanoma cells. These findings suggest that targeting the tumor-associated pHe level could be an effective strategy for the drug function of Ru(II)-nitrite compounds.
Assuntos
Antineoplásicos , Cisplatino , Complexos de Coordenação , Cimenos , Resistencia a Medicamentos Antineoplásicos , Melanoma , Óxido Nítrico , Nitritos , Rutênio , Cisplatino/farmacologia , Cisplatino/química , Humanos , Rutênio/química , Rutênio/farmacologia , Melanoma/tratamento farmacológico , Melanoma/patologia , Melanoma/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Cimenos/farmacologia , Cimenos/química , Nitritos/química , Nitritos/farmacologia , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Complexos de Coordenação/síntese química , Linhagem Celular Tumoral , Óxido Nítrico/metabolismo , Monoterpenos/farmacologia , Monoterpenos/química , Morte Celular/efeitos dos fármacosRESUMO
Dinitrosyl iron unit (DNIU), [Fe(NO)2], is a natural metallocofactor for biological storage, delivery, and metabolism of nitric oxide (NO). In the attempt to gain a biomimetic insight into the natural DNIU under biological system, in this study, synthetic dinitrosyl iron complexes (DNICs) [(NO)2Fe(µ-SCH2CH2COOH)2Fe(NO)2] (DNIC-COOH) and [(NO)2Fe(µ-SCH2CH2COOCH3)2Fe(NO)2] (DNIC-COOMe) were employed to investigate the structure-reactivity relationship of mechanism and kinetics for cellular uptake of DNICs, intracellular delivery of NO, and activation of cytoprotective heme oxygenase (HO)-1. After rapid cellular uptake of dinuclear DNIC-COOMe through a thiol-mediated pathway (tmax = 0.5 h), intracellular assembly of mononuclear DNIC [(NO)2Fe(SR)(SCys)]n-/[(NO)2Fe(SR)(SCys-protein)]n- occurred, followed by O2-induced release of free NO (tmax = 1-2 h) or direct transfer of NO to soluble guanylate cyclase, which triggered the downstream HO-1. In contrast, steady kinetics for cellular uptake of DNIC-COOH via endocytosis (tmax = 2-8 h) and for intracellular release of NO (tmax = 4-6 h) reflected on the elevated activation of cytoprotective HO-1 (â¼50-150-fold change at t = 3-10 h) and on the improved survival of DNIC-COOH-primed mesenchymal stem cell (MSC)/human corneal endothelial cell (HCEC) under stressed conditions. Consequently, this study unravels the bridging thiolate ligands in dinuclear DNIC-COOH/DNIC-COOMe as a switch to control the mechanism, kinetics, and efficacy for cellular uptake of DNICs, intracellular delivery of NO, and activation of cytoprotective HO-1, which poses an implication on enhanced survival of postengrafted MSC for advancing the MSC-based regenerative medicine.