Finding a cell-permeable compound to inhibit inflammatory cytokines: Uptake, biotransformation, and anti-cytokine activity of javamide-I/-II esters.

Aim: Currently, there is limited information available about cell-permeability and anti-cytokine activity of javamide-I/-II esters in monocyte/macrophage-like cells. Therefore, the aim of this study was to investigate their cell-permeability and anti-cytokine activity in the cells.
Materials and Methods: The uptake of javamide-I/-II and esters was studied in THP-1 cells and PBMCs. Also, kinetic and inhibition studies were conducted using THP-1 cells. Western Blot was performed to determine the level of ATF-2 phosphorylation in THP-1 cells, and ELISA assays were carried out to measure TNF-alpha, MCP-1, IL-1beta and IL-8 levels in PBMCs.
Key Findings: In THP-1 cells, the uptake of javamide-I/-II esters was significantly higher than javamide-I/-II (P < 0.001), and the K _m for javamide-I ester was 27 μM. Also, the uptake of the esters was inhibited by PepT2 substrate/blocker. In THP-1 cells, javamide-I/-II esters were also biotransformed into javamide-I/-II. Furthermore, javamide-I ester could inhibit ATF-2 phosphorylation better than javamide-I in the cells, suggesting that the ester could be transported inside the cells better than javamide-I. Similarly, javamide-I/-II esters were found to be transported and biotransformed in PBMCs involved in inflammation processes. As anticipated, the esters were found to inhibit TNF-alpha and MCP-1 significantly in PBMCs (P < 0.005). Especially, javamide-I ester inhibited TNF-alpha, MCP-1, IL-1beta and IL-8 with IC ₅₀ values of 1.79, 0.88, 0.91 and 2.57 μM in PBMCs.
Significance: Javamide-I/-II esters can be transported, biotransformed and inhibit inflammatory cytokines significantly in monocyte/macrophage-like cells, suggesting that they may be utilized as a potent cell-permeable carrier to inhibit inflammatory cytokines in the cells.
Chemical Compounds: Javamide-I, javamide-I-O-methyl ester, javamide-II, javamide-II-O-methyl ester, tryptophan, coumaric acid, caffeic acid, GlySar, enalapril.
(Published by Elsevier Inc.)