Attenuation of LPS-induced Immune Responses

• Main Authors: Chu-Chun Hsieh, 謝筑鈞
• Other Authors: Paulus S. Wang
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/41904476295504769468

碩士 === 國立陽明大學 === 生理學研究所 === 103 === Tomatine, a glycoalkaloid found in tomato (Solanum lycopersicum) plants and leaves, its structure is similar to an anti-inflammatory steroid cotisol. It has been well known that tomatine possesses both antitumor and antioxidant effects. Although the chemical structure of tomatine is similar to glucocorticoid, the anti-inflammatory mechanism of tomatine is unclear. The present study was designed to explore the effects and the action mechanism of tomatine against lipopolysaccharide (LPS)-induced inflammation in splenocytes isolated from male rats both in vitro and in vivo. The concentrations of tumor necrosis factor alpha (TNF-α), interleukin-1 beta (IL-1β) and nitric oxide (NO) were measured by enzyme-linked immunosorbent assay (ELISA) and Griess reagent. The protein expressions of extracellular signal-regulated kinase 1/2 (ERK1/2), nuclear factor (NF)-κB, p38 and protein kinase B (Akt) were evaluated by Western blot techniques. Our data show that the secretions of TNF-α, IL-1βand NO induced with LPS were decreased in cells after administration of tomatine by a dose-dependent manner. Administration of tomatine attenuated the production of cytokine by inhibiting ERK1/2 and NF-κB phosphorylation after induction by LPS. In addition, tomatine effect was associated with upregulation of the Akt phosphorylation. In another study, subcutaneous injection of tomatine (0.4 mg/kg, 2 mg/kg) once daily for 7 days in rats markedly decreased the TNF-α and IL-β production in splenocytes after LPS treatment. In conclusion, we have demonstrated that tomatine suppressed inflammation through inhibiting the phosphorylation of ERK1/2 and NF-κB and increasing Akt phosphorylation.