Background: Several chemical modifications have been developed to overcome the toxicity of amphotericin B (AmB). Oxidized forms of AmB (AmB-ox), which may occur in patient's circulation during therapy, are as toxic as AmB. Complexes with copper (II) ions (AmB-Cu2+) have been reported to be less toxic to human cells. Previous studies showed that AmB changed the expression of transforming growth factor-beta (TGF-β). Therefore, the objective of this study was to investigate the influence of AmB and its modified forms on the expression of genes encoding for TGF-β family members and related proteins in renal cells.
Methods: Human renal proximal tubule cells (RPTEC) were treated with AmB-Cu2+, AmB, or the oxidized form AmB-ox. The expression of TGF-β family members and related genes was determined using oligonucleotide microarrays. TGF-β1 protein level was determined using ELISA method. The mRNA level of TGF-β isoforms, TGF-β receptors and differentiating genes was evaluated by real-time RT-qPCR.
Results: AmB-Cu2+ increased the mRNA levels of TGF-β1 and TGF-β2 isoforms and two genes encoding receptors: TGFBR1 and TGFBR2. TGF-β1 protein level in culture medium was not increased after stimulation with AmB-Cu2+. Microarray analysis revealed changes in both pro-fibrotic and anti-fibrotic genes.
Conclusions: These results suggest that AmB-Cu2+ may induce repair mechanisms in renal proximal tubule cells via changes in the expression of genes involved in intracellular signaling.
Keywords: Amphotericin B; Copper complexes; Oligonucleotide microarrays; Real-time RT-qPCR; TGF-β isoforms; TGF-β receptors.
Copyright © 2017 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.