Abstract:
Study involved with potassium channel KCa3.1 blocker (triarylmethane-34; TRAM-34) in doxorubicin (DOX)-induced feline kidney cells was performed. The study was divided into two parts. In part I, subtoxic dose of TRAM-34 in feline kidney cell lines was studied to determine the cytotoxicity of TRAM-34 in feline kidney cells by cytotoxicity assay. In part II, feline kidney cell lines were incubated with appropriate dose and time of TRAM-34 pretreatment for 24 h or 30 min and post-treatment for 24 h condition in DOX-induced cell toxicity. Cytotoxicity assay, apoptosis and necrosis assay and KCa3.1 protein expression were measured. The cytotoxicity results indicated no significantly differences in cell viability between cells treated with TRAM-34 at 0.1 to 100 µM concentration and negative control in 24 h but a significant reduction of cell surviving at 100 µM concentration of TRAM-34 in 48 h (p<0.05). We found subtoxic dose of TRAM-34 in feline kidney cells lines at the concentration 100 µM in 24 h, 50 µM in 48 h and 25 µM in 96 h when compared with the negative control. Pretreatment with TRAM-34 at 0.1 to 1 µM concentrations for 24 h had significantly higher percentages of cell viability (p<0.05) and significantly lower percentages of apoptotic cells respect to the total than DOX-treated control (p<0.05) but was not significantly different in percentages of necrosis cells than DOX-treated control. Moreover, Pretreatment with TRAM-34 at the 0.1 µM concentrations for 24 h had significantly decreased KCa3.1 protein expression when compared with DOX-treated control (p<0.05). Therefore, these findings suggested that TRAM-34 can protect feline kidney cells line from DOX-induced toxicity by inhibiting KCa3.1 channel. KCa3.1 channel blocker may be used as one of the potential therapeutic treatment for cats with naturally-occurring chronic kidney disease in the future.
