Abstract 5257: Cellular pharmacology of curcumin cellular pharmacology of curcumin±piperine

Abstract Rationale: Prior reports have suggested that piperine, the major alkaloid product derived from black and long pepper, enhances curcumin’s cancer preventive efficacy in vitro and in vivo by an intracellular pharmacokinetic interaction; yet, no previous studies have explored the pharmacokinetic interactions between curcumin and piperine. Methods: We incubated non-transformed breast cell line MCF10A and breast cancer SUM149 cell line with different concentrations of curcumin, piperine or curcumin + piperine to assess cell viability using a MTT assay. For curcumin and piperine uptake assays, we incubated MCF10A, SUM149 and MCF7 breast cells with either 5 µM curcumin or 5 µM curcumin + 5 µM piperine for 0.5, 1, 4,6,8,12 and 24 h, or with 15 µM curcumin or 15 µM curcumin + 10 µM piperine for 0.17, 0.5, 1,2 and 4h. Media and cell lysates were extracted for assay of intracellular curcumin and piperine by LC-MS/MS. ALDH+ , ALDH-CD44+24- cells were collected via FACS, incubated with 15 µM curcumin or 15 µM curcumin + 10 µM piperine for 1 hour. Cell lysates and media were assayed for curcumin, curcumin degradation and metabolic products and quantified using LC-MS/MS. Results: 90.7±0.06% and 34.8 ±0.002% of cells were viable after incubating MCF10A and SUM149 cells respectively with 25 µM curcumin compared to DMSO control. Incubation with 10 µM Piperine enhanced the antiproliferative effect of 15 µM curcumin by 33.6±0.015% (P< 0.05) and 16.3±0.003% (P<0.05) in SUM149 and MCF10A cells respectively. We found no significant increase of intracellular concentration of curcumin when coincubated with piperine in the MCF10A, MCF7 and SUM149 cells or in the ALDH+ and the ALDH- CD44+CD24- SUM149 cells. Curcumin intracellular concentration was 166.7±22 and 151.5±24 ng/mg protein in ALDH+ cells for curcumin alone or curcumin + piperine respectively and 130±25.4 and 135±27.4 ng/mg protein in ALDH- CD44+CD24- for curcumin alone or curcumin + piperine respectively in SUM149 cell line. Curcumin uptake was lower in MCF10A cells than SUM149 cells. The intracellular curcumin concentration after 1 hour incubation with 5 µM curcumin was 11.8±0.8 and 68.1±11.2 in MCF10A and SUM149 cells respectively. Tetrahydrocurcumin and curcumin sulfate conjugates were the major metabolites detected in MCF7 and SUM149 cell lines. Curcumin sulfate is detectable in the media as early as 0.5h, it increases from 1.36±0.06 and 1.43±0.05 after 0.5h to 22.6±0.53 and 23±2.2 ng/ml after 4 h for curcumin and curcumin + piperine respectively in the media of ALDH-CD44+Cd24- SUM149 cells. Conclusions: We find no significant difference in intracellular curcumin concentration between cells treated with curcumin alone or curcumin + piperine after incubation times up to 24 hr. The additive cellular toxicity effects observed with piperine + curcumin is not pharmacokinetic (associated with efflux pump inhibition) but rather pharmacodynamic due to piperine’s independent anti-proliferative effects. Citation Format: Rama Mahran, Pan Shu, Duxin Sun, Dean E. Brenner. Cellular pharmacology of curcumin cellular pharmacology of curcumin±piperine [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5257. doi:10.1158/1538-7445.AM2017-5257