High glucose up-regulates TRAIL-R4 expression in THP-1 cells and smooth muscle cells

AIM: To evaluate the expression of TNF-related apoptosis inducing ligand receptor 4 (TRAIL-R4) of THP-1 cells and human aorta smooth muscle cells under high glucose intervention. METHODS: Monocytic cell line THP-1 was incubated with PMA to induce to mature macrophage, Adhesion molecules CD11b and CD11c were assessed by FACS. TRAIL-R4 levels in THP-1 cells treated with different glucose concentrations were determined by Western blotting. The changes of TRAIL-R4 protein expressions were observed at different time points in human aorta smooth muscle cells. Western blotting was employed to evaluate TRAIL-R4 levels after the intervention of PKC activator. RESULTS: Incubation with 160 nmol/L PMA induced mature macrophages. TRAIL-R4 expression was up-regulated after incubation with 20 mmol/L glucose in macrophages. TRAIL-R4 was elevated in a time course manner under high glucose level in human aorta smooth muscle cells. Moreover, activation of PKC induced TRAIL-R4 expressions. CONCLUSION: Up-regulated TRAIL-R4 protein levels induced by high glucose levels might inhibit apoptosis of monocytes and smooth muscle cells and contribute to the progression of atherosclerosis.