BACKGROUND: There is rapidly accumulating evidence that use of oxidized hair dye causes various forms of nephrotoxic injury. However, the regulation and implication of the nephrotoxic injury resulting from p-aminophenol (PAP) and p-paraphenylenediamine (PPD), the main components of oxidized hair dye, remain unknown. METHODS: To clarify the effect of PAP and PPD, we analyzed the proliferation, lactate dehydrogenase (LDH) levels, apoptosis and subsequent mRNA levels of caspase-3 in HK-2 cells stimulated with different concentrations of PAP or PPD. Cell proliferation was assessed by MTT assay. The production of LDH was determined by Hitachi 7170 biochemical analyzer. The apoptosis of cell was analyzed using flow cytometry and scanning electron microscopy. The mRNA levels of caspase-3 were quantitatively measured by real-time PCR. RESULTS: The proliferation of HK-2 cells was significantly inhibited by PAP, PPD and each mixed with hydrogen peroxide (H2O2). The level of apoptosis of HK-2 cells, the mRNA levels of caspase-3 and LDH production by PAP or PPD stimulation was significantly higher than controls or after H2O2. A typical apoptotic morphological change was observed under electron microscopy in response to PAP or PPD. CONCLUSION: It appears that caspase-3 may play a key role in the nephrotoxic injury resulting from PAP, PPD or its oxidized form.
BACKGROUND: There is rapidly accumulating evidence that use of oxidized hair dye causes various forms of nephrotoxic injury. However, the regulation and implication of the nephrotoxic injury resulting from p-aminophenol (PAP) and p-paraphenylenediamine (PPD), the main components of oxidized hair dye, remain unknown. METHODS: To clarify the effect of PAP and PPD, we analyzed the proliferation, lactate dehydrogenase (LDH) levels, apoptosis and subsequent mRNA levels of caspase-3 in HK-2 cells stimulated with different concentrations of PAP or PPD. Cell proliferation was assessed by MTT assay. The production of LDH was determined by Hitachi 7170 biochemical analyzer. The apoptosis of cell was analyzed using flow cytometry and scanning electron microscopy. The mRNA levels of caspase-3 were quantitatively measured by real-time PCR. RESULTS: The proliferation of HK-2 cells was significantly inhibited by PAP, PPD and each mixed with hydrogen peroxide (H2O2). The level of apoptosis of HK-2 cells, the mRNA levels of caspase-3 and LDH production by PAP or PPD stimulation was significantly higher than controls or after H2O2. A typical apoptotic morphological change was observed under electron microscopy in response to PAP or PPD. CONCLUSION: It appears that caspase-3 may play a key role in the nephrotoxic injury resulting from PAP, PPD or its oxidized form.
Authors: Kazuhisa Miyakawa; Ryan Albee; Lynda G Letzig; Andreas F Lehner; Michael A Scott; John P Buchweitz; Laura P James; Patricia E Ganey; Robert A Roth Journal: J Pharmacol Exp Ther Date: 2015-06-11 Impact factor: 4.030