Abstract

Cocus nucifera milk enhances liver cell viability and down-regulates nuclear hormone receptorRXR-but not PPAR-expression in high dose

Author(s): Hong-Kin Wong, Choy-Hoong Chew

The use of coconut milk in daily diet often worried consumers as they believe this high fat food product leads to increase risk of acquiring obesity and cardiovascular diseases. However, in contrast to common believe, several studies showed that coconut fatmight be capable of improving the cardiovascular function and atherosclerotic conditions. In order to justify the actual health role of coconutmilk, this studywas designed to investigate the potential molecular effect of coconut milk in modulating human lipid metabolism using the popular in vitro surrogate of liver – human hepatocarcinoma HepG2 cell line. The cytotoxic effect of coconut milk againstHepG2 cell viabilitywas first studied by usingMTT assay. Coconut milk treatmentwas shown to improve liver cell viability in a dose dependent manner. To access the influence of coconut milk on the transcriptional response of lipid activated nuclear receptor (namely PPAR-á, and RXR-á) inHepG2 cell line,Real-TimeReverse Transcription PCRwas performed on the total mRNA sample extracted from the coconut milk treated cell specimen. Besides that, Western blotting was also used to analyse the protein expression. The Real-Time PCR results revealed that the increasing amount of coconutmilk negatively influenced the expression of both PPAR- á and RXR-á mRNA by approximately 27% and 36%, respectively. Meanwhile, no significant results were obtained from the Western assay. In a nutshell, this study showed that the application of coconut milk did not alter the cell viability at all tested concentration, while the normal lipid metabolism was only maintained when it was administered at low dose.