Effect of cinnamon water extract on monocyte-to-macrophage differentiation and scavenger receptor activity

Kang, Hee; Park, Sung-Hyun; Yun, Jeong-Moon; Nam, Tae-Gyu; Kim, Young-Eun; Kim, Dae-Ok; Kim, Youn Jung

The human monocytic cell line THP-1 is a suspension cell type resembling circulating primary monocytes. Treatment with PMA causes these cells to stop mitosis, adhere to the culture plate, and differentiate into mature macrophages [15] . Before assessing the bioactivity of CWE, we examined whether CWE caused cytotoxicity in PMAstimulated cells. CWE was not toxic to cells for 24 and 48 h, but the maximum concentration assayed here (400 μg/ml) caused a 10% decrease in cell viability at the end of 72 h culture period (Figure 2A) . Then, we measured whether CWE affects gene expression of the scavenger receptors, type 1 macrophage scavenger receptor (SRA) and CD36, and the macrophage-specific integrin, CD11b using real-time PCR. These differentiation markers are upregulated in response to PMA [16] [17] [18] . CWE treatment reduced the expression levels of CD11b and CD36 in a concentration-dependent manner ( Figures 2B,C) . The reduction of SRA gene occurred only at 100 μg/ml, but the magnitude was marked compared with the other differentiation markers ( Figure 2D ).