Setsuo Hamada

Trehalose inhibits inflammatory cytokine production by protecting IκB-α reduction in mouse peritoneal macrophages

OBJECTIVE The aim of this study was to examine whether trehalose, a disaccharide, could inhibit Porphyromonas gingivalis (P. gingivalis) lipopolysaccharide (LPS)-enhanced production of inflammatory cytokines in mouse peritoneal macrophages. DESIGN Mouse peritoneal macrophages were treated with trehalose and stimulated with P. gingivalis LPS. Interleukin-1beta (IL-1beta) and tumour necrosis factor-alpha (TNF-alpha) levels in the culture supernatant were measured by ELISA. The mRNA levels of the cytokines in macrophages were analysed by semi-quantitative RT-PCR. DNA and protein synthesis were measured by incorporation of [(3)H] thymidine or [(14)C] praline into mouse peritoneal macrophages. IkappaB-alpha reductions were assessed by western blot. RESULTS Treatment with trehalose suppressed LPS-induced IL-1beta and TNF-alpha production and downregulated transcription of these cytokines. Furthermore, trehalose inhibited LPS-induced reduction of IkappaB-alpha. In addition, we also observed expression of the trehalose receptor (T1R3) in mouse peritoneal macrophages. CONCLUSION These results may suggest that trehalose inhibits LPS-induced production of IL-1beta and TNF-alpha in mouse peritoneal macrophages by inhibiting degradation of IkappaB-alphavia the trehalose receptor T1R3.