金花葵萃取物對脂多醣所誘發神經小膠質細胞發炎反應之抗發炎機轉研究

Investigating anti-inflammatory effects of Abelmoschus manihot extract on Lipopolysaccharide-stimulated murine microglia cell BV2

吳珊瑜(shan-yu wu)

指導教授 ： 高紹軒

中山醫學大學/醫學院/生化暨生物科技研究所/碩士(2013年)

https://doi.org/10.6834/CSMU.2013.00168

摘要

神經小膠質細胞是中樞神經系統中主要的免疫細胞之一，只要環境出現一點的微變化或受到一些外在刺激，它們便很容易被活化，可想而知它們是一群非常敏感的細胞。而活化的神經小膠質細胞就會具有吞噬能力並且會分泌促發炎因子，若一直持續活化則是會對中樞神經系統造成傷害。
本實驗是利用小鼠的神經小膠質細胞株BV-2，使用脂多醣 (LPS)做刺激使細胞活化，以探討金花葵萃取物抗發炎作用及機轉。
在本研究中我們發現以(5，10，50μg/ml)濃度的金花葵萃取物(Abelmoschus manihot extract，AME)可降低脂多醣引發的發炎因子，包含 iNOS 以及 COX-2等mRNA及蛋白質的生成。並發現AME也會降低LPS所誘導的NO。由此，我們更進一步探討AME抑制脂多醣所誘導的發炎反應是透過哪一條發炎路徑，確實發現可以降低脂多醣所誘導的磷酸化MAPK家族(包含了ERK、JNK、P38 ) ，此外，也發現AME抗發炎的效果，也會影響NF-κB無法轉入到細胞核內，而抑制轉錄因子NF-κB訊息的活化。綜合以上結果，可以得知在AME的給予下，明顯降低脂多醣所誘導的前發炎的因子如COX-2和iNOS 的mRNA並且抑制其蛋白生成，是透過抑制MAPK家族，使NF-κB無法轉錄到細胞核內，進而抑制下游的發炎基因。

關鍵字

金花葵萃取物 ； 神經小膠質細胞

並列摘要

Microglia are resident immune cells in the normal brain and play a crucial role in the innate immune response in the central nervous system，continuous or over acting might be harmful to the central nervous system。Microglia are activated by extracellular stimuli such as lipopolysaccharide , interferon-γ , and β-amyloid and activated microglial cells initiated several major cellular responses that play important roles in the pathogenesis of inflammation。
Previous studies have show that Abelmoschus manihot extract (AME) has demonstrated significant anti-inflammatory activity in kidney disease，thus it was hypothesized that effect of Abelmoschus manihot extract (AME) would suppresses lipopolysaccharide(LPS) induces neuroinflammatory responses in BV2 microglia cell.
We used BV-2 microglia cell line to study the anti-neuroinflammatory mechanism of Abelmoschus manihot extract (AME). Abelmoschus manihot extract (AME) at concentrations ranging from 5 to 100 μg/ml did not affect cell viability using MTT assay. LPS increase the production of nitric oxide by sevenfold,however, Abelmoschus manihot extract (AME) effectively antagonized LPS-induced nitric oxide production.and RT-PCR data suggest, Abelmoschus manihot extract (AME) effectively inhibited LPS- induced iNOS, COX-2 expression.and we found AME suppressed the LPS induced phosphorylation of MAPK including ERK1/2、JNK、p38.

並列關鍵字

Abelmoschus manihot extract ； BV2 cell

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