JKB-122 is effective, alone or in combination with prednisolone in Con A-induced hepatitis.

Con A-induced hepatitis in mice is an established model of autoimmune hepatitis (AIH). JKB-122, a toll-like receptor 4 (TLR4) antagonist, was tested for hepatotprotectant activity. Within several hours of Con A challenge (15mg/kg iv), increased production of proinflammatory cytokines with inflammatory infiltrate occurred in the liver. The severity of tissue necrosis and the amount of circulating liver enzymes peak at 24h post Con A challenge. JKB-122 was given 24 and 16h before, then concurrently, and 4 and 8h (× 5 doses) after challenge with Con A. Serum and liver were harvested at 3, 9 and 24h post Con A challenge. JKB-122 at 20 and 50mg/kg po prevented the increase of serum liver enzymes by 47% and 95% respectively vs vehicle control 24h post Con A. JKB-122 significantly inhibited Con A-induced pathological lesions in the liver and the amount of IFN-γ IL-1ß, IL-4, IL-5, IL-6, IL-17A and TNF-α starting as early as 3h post Con A. Moreover, JKB-122 given concurrently (× 3 doses) with Con A showed similar effect. Finally, JKB-122 enhanced the therapeutic effects of submaximal dose of prednisolone with improved lesion score. It is concluded that JKB-122 at 20 and 50mg/kg po caused dose-dependent inhibition of elevated liver enzymes in Con A-induced hepatitis in mice, indicating hepatoprotectant activity. The results suggest that JKB-122 as monotherapy or in combination with prednisolone may offer a viable approach to the treatment of AIH.

Effects of alpha-mangostin on the expression of anti-inflammatory genes in U937 cells.

BACKGROUND: α-Mangostin (α-MG) is a main constituent of the fruit hull of the mangosteen. Previous studies have shown that α-MG has pharmacological activities such as antioxidant, antitumor, anti-inflammatory, antiallergic, antibacterial, antifungal and antiviral effects. This study aims to investigate the anti-inflammatory molecular action of α-MG on gene expression profiles. METHODS: U937 and EL4 cells were treated with different concentrations of α-MG in the presence of 0.1 ng/mL lipopolysaccharide (LPS) for 4 h. The anti-inflammatory effects of α-MG were measured by the levels of tumor necrosis factor (TNF)-α and interleukin (IL)-4 in cell culture media, which were determined with enzyme-linked immunosorbent assay kits. The gene expression profiles of all samples were analyzed with a whole human genome microarray, Illumina BeadChip WG-6 version 3, containing 48804 probes. The protein levels were determined by Western blotting analyses. RESULTS: α-MG decreased the LPS induction of the inflammatory cytokines TNF-α (P = 0.038) and IL-4 (P = 0.04). α-MG decreased the gene expressions in oncostatin M signaling via mitogen-activated protein kinase (MAPK) pathways, including extracellular signal-regulated kinases (P = 0.016), c-Jun N-terminal kinase (P = 0.01) , and p38 (P = 0.008). α-MG treatment of U937 cells reduced the phosphorylation of MAPK kinase 3 / MAPK kinase 6 (P = 0.0441), MAPK-activated protein kinase-2 (P = 0.0453), signal transducers and activators of transcription-1 (STAT1) (P = 0.0012), c-Fos (P = 0.04), c-Jun (P = 0.019) and Ets-like molecule 1 (Elk-1) (P = 0.038). CONCLUSION: This study demonstrates that α-MG attenuates LPS-mediated activation of MAPK, STAT1, c-Fos, c-Jun and EIK-1, inhibiting TNF-α and IL-4 production in U937 cells.