Effects of terpenoids on Th1/Th2 immune responses in vitro and in vivo

• Main Authors: Chi-Mei Ku, 顧琪玫
• Other Authors: Jin-Yuarn Lin
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/m5bvkf

碩士 === 國立中興大學 === 食品暨應用生物科技學系所 === 100 === Terpenoids, also called isoprenoids, are a group of compounds that exist in nearly every natural plant and most of them are important secondary metabolites in plant. Based on the number of building blocks, terpenoids are classified into monoterpenoids, sesquiterpenoids, diterpenoids, triterpenoids and tetraterpenoids. Several studies have evidenced that terpenoids have beneficial impact in body for anti-inflammatation, anti-oxidantion, anti-biotic effect and anti-cancer; however, effects of terpenoids on allergic asthma remain unclear. Allergic asthma is a chronic airway inflammatory disease, resulting from helper T cells type 2 (Th2)-skewed immune responses. Thus, asthma may be improved through modulating Th1/Th2 immune balance. To screen potent compounds for allergic asthma treatment, this study selected 27 terpenoids with immunomodulatory potential and investigated their effects on Th1/Th2 immune responses using primary splenocytes in vitro. Th1 and Th2 cytokines were determined using ELISA. The results showed that farnesol reduced interleukin (IL)-10/IL-2 cytokine ratios in a dose-dependent manner, suggesting that farnesol might modulate Th2/Th1 balance toward Th1 immune response. Therefore, farnesol was further administered to ovalbumin (OVA)-sensitized and -challenged BALB/c mice for 5 weeks. The results showed that farnesol supplementation decreased pro-inflammatory (tumer necrosis factor-α, TNF-α)/anti-inflammatory (IL-10) cytokine secretion ratios by peritoneal cells, and serum OVA-specific and non-specific antibody titers, but increased high-density lipoprotein cholesterol (HDL-c) level in sera. These results suggested that farnesol might modulate Th2 immune responses toward Th1 balance in allergic asthmatic mice and alleviate allergic inflammation responses. In conclusion, the sesquiterpenoid farnesol may modulate Th1/Th2 immune responses in vitro and in vivo and improve allergic diseases.