Session Type: ePosters
Session Title: ePosters
Authors(s): A. Payasi, S. Chaudhary, M. Chaudhary, A. Sharma, A. Aggarwal
Authors Affiliations(s): Venus Medicine Research Centre, India
Background:
Polymyxin B is cytotoxic to renal tubular cells and is prone to cause nephrotoxicity in vivo because of the renal handling mechanisms that facilitate the accumulation of this drug in these cells. This often results in suboptimal dosing regimens. With the aim of significantly reducing the polymyxin B-induced nephrotoxicity, a supramolecular cationic complex (SMC) of polymyxin B (VRP-034) is being developed. The objective of this study was to compare the in vitro cytotoxicity of VRP-034 vs marketed polymyxin B in the cultured rat (NRK-52E) and human (HK-2) kidney proximal tubule epithelial cell lines.
Methods:Suspensions of NRK-52E and HK-2 were seeded (5000 cells/well) onto 96-well plates. After 24h of pre-incubation, VRP-034 and marketed polymyxin B were added to each well at different concentrations (up to 768 µg/ml). Gentamicin sulphate was used as a positive control. Cell viability was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay after 24h and 48h of drug exposure, and IC50 (drug concentration resulting in 50% of maximal reduction in cell viability) values were estimated. Each drug concentration was tested in triplicates and each test was repeated three times. All values are expressed as mean ± SEM.
Results:Both VRP-034 and marketed polymyxin B exhibited concentration-dependent inhibitory effects on the NRK-52E and HK-2 cells, with VRP-034 showing significantly lower cytotoxic activity across both cell lines. In the NRK-52E cell line, the IC50 (µg/mL) of VRP-034 was 42% (368.2±26.80 vs. 259.2±19.95; p<0.01) and 81% (185.4±15.68 vs. 102.4±11.26; p<0.0001) higher than marketed polymyxin B at 24h and 48h respectively. Similarly, in the HK-2 cell line, IC50 of VRP-034 was 63% (147±8.87 vs. 90.43±4.30; p<0.0001) and 78% (86.27±3.58 vs. 48.53±1.91; p<0.0001) higher at 24h and 48h respectively. In both treatment groups, HK-2 cells were more sensitive to damage than NRK-52E cells.
Conclusions:The evidence suggests that VRP-034 is markedly less cytotoxic than marketed polymyxin B in rat and human kidney proximal tubular cell lines, however, further research is warranted to fully elucidate its role in attenuating polymyxin-induced nephrotoxicity.
Keyword(s): Polymyxin B, Cytotoxicity, Drug-Induced Kidney InjuryCOI Stock Options: Yes
Session Type: ePosters
Session Title: ePosters
Authors(s): A. Payasi, S. Chaudhary, M. Chaudhary, A. Sharma, A. Aggarwal
Authors Affiliations(s): Venus Medicine Research Centre, India
Background:
Polymyxin B is cytotoxic to renal tubular cells and is prone to cause nephrotoxicity in vivo because of the renal handling mechanisms that facilitate the accumulation of this drug in these cells. This often results in suboptimal dosing regimens. With the aim of significantly reducing the polymyxin B-induced nephrotoxicity, a supramolecular cationic complex (SMC) of polymyxin B (VRP-034) is being developed. The objective of this study was to compare the in vitro cytotoxicity of VRP-034 vs marketed polymyxin B in the cultured rat (NRK-52E) and human (HK-2) kidney proximal tubule epithelial cell lines.
Methods:Suspensions of NRK-52E and HK-2 were seeded (5000 cells/well) onto 96-well plates. After 24h of pre-incubation, VRP-034 and marketed polymyxin B were added to each well at different concentrations (up to 768 µg/ml). Gentamicin sulphate was used as a positive control. Cell viability was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay after 24h and 48h of drug exposure, and IC50 (drug concentration resulting in 50% of maximal reduction in cell viability) values were estimated. Each drug concentration was tested in triplicates and each test was repeated three times. All values are expressed as mean ± SEM.
Results:Both VRP-034 and marketed polymyxin B exhibited concentration-dependent inhibitory effects on the NRK-52E and HK-2 cells, with VRP-034 showing significantly lower cytotoxic activity across both cell lines. In the NRK-52E cell line, the IC50 (µg/mL) of VRP-034 was 42% (368.2±26.80 vs. 259.2±19.95; p<0.01) and 81% (185.4±15.68 vs. 102.4±11.26; p<0.0001) higher than marketed polymyxin B at 24h and 48h respectively. Similarly, in the HK-2 cell line, IC50 of VRP-034 was 63% (147±8.87 vs. 90.43±4.30; p<0.0001) and 78% (86.27±3.58 vs. 48.53±1.91; p<0.0001) higher at 24h and 48h respectively. In both treatment groups, HK-2 cells were more sensitive to damage than NRK-52E cells.
Conclusions:The evidence suggests that VRP-034 is markedly less cytotoxic than marketed polymyxin B in rat and human kidney proximal tubular cell lines, however, further research is warranted to fully elucidate its role in attenuating polymyxin-induced nephrotoxicity.
Keyword(s): Polymyxin B, Cytotoxicity, Drug-Induced Kidney InjuryCOI Stock Options: Yes