植物雌激素 (香豆醇及二羥基異黃酮) 對抗Ab及LPS誘發之毒性在小鼠星狀神經膠細胞的保護效果

The Protective Effects of Phytoestrogen (Coumestrol and Daidzein) against Amyloid-??-peptide and LPS-induced Toxicity on Mice Astrocyte Cells

劉滿海(Man-Hai Liu)

指導教授 ： 許秀蘊

共同指導教授 ： 孫瑞昇

臺北醫學大學/藥學院/藥學系(博士班)/博士(2010年)

https://doi.org/10.6831/TMU.2010.00114

摘要

從流行病學及回朔以往病例顯示雌激素補充療法(ERT)可以降低阿滋海默氏症發生率,植物雌激素已經被建議可以當作與雌激素補充療法二者具選擇之潛力藥物.本研究主要證明香豆醇在小鼠體外試驗是否具有類雌激素作用,並且研究植物雌激素daidzein和香豆醇(coumestrol)之神經保護及抗氧化效果.
以加入兩種毒性物質(LPS(脂多醣)及A??(類澱粉蛋白胜肽))至星狀神經膠細胞之模式,探討daidzein和香豆醇(coumestrol)對於星狀神經膠細胞保護之效果.細胞活性可以MTT去分析,對於細胞保護之效果與路徑可以經由測定特殊基因表現和蛋白質含量之改變.結果證明daidzein和香豆醇(coumestrol)可以顯著增加細胞活性,但再加入 LPS及A?珓廗|降低細胞活性.本研究主要是探討在受到Aβ和LPS的刺激之前，先加入具有抗發炎作用的藥物 daidzein及香豆醇(coumestrol)，是否能減少誘導發炎的物質產生。結果顯示daidzein香豆醇(coumestrol)皆可以降低細胞白介素第一因子??(interleukin-1??(IL-1??))、細胞白介素第六因子 (interleukin-6 (IL-6)) 和腫瘤壞死因子α(tumor necrosis factor-alpha (TNF-α))的mRNA表現及蛋白質含量.
神經退化疾病之路徑仍是不明確,尚有許多阿滋海默氏症的假設,我們結果提供daidzein和香豆醇是既安全又有神經保護作用及有效抑制發炎反應,在新生鼠星狀神經膠細胞模式中 daidzein 和 coumestrol 最適當之劑量分別為10-12M ,10-9M.此結果顯示其在阿滋海默氏症之預防及治療上具有發展之潛力.

關鍵字

香豆醇 ； 二羥基異黃酮 ； 星狀神經膠細胞

並列摘要

Phytoestrogens have been proposed as potential alternatives to ERT in treatment of AD. The purpose of this study was to demonstrate the in vitro effects of Daidzein and coumestrol on mice glial cells to determine whether coumestrol exert estrogen agonist effect in neural tissue and investigate its neuroprotective and anti-inflammatory efficacy.

Different concentrations of daidzein and coumestrol were tested for their neuroprotective efficacy against two toxic insults, lipopolysaccharide (LPS) and amyloid-beta-peptide(25-35)[Aβ(25–35)] neurotoxicity. Neuronal mitochondrial activity was determined by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay, The protective efficacy and pathway were examined by their specific gene expression and protein changes.
Results of these studies demonstrated that daidzein and coumestrol induced a modest but significant increase in MTT levels, the reduction in MTT levels following exposure to LPS and ??-amyloid25–35. The present study is to see whether daidzein and coumestrol, known to have anti-inflammation activity, is able to inhibit the production of proinflammatory mediators by using two stimulants, Aβ and lipopolysaccharide (LPS). The results indicate that daidzein and coumestrol are able to down-regulated mRNA expression of IL-1,IL-6 and TNF-α under Aβ and LPS treatments .
The pathway of neurodegrative disease is not very clear and there are many hypothesis about Alzheimer’s disease)(AD). Our results provide that daidzein and coumestrol are both safe neuroprotective agents and effective in inhibiting the inflammation with optimum dose at 10-12M and 10-9M on neonatal mice astrocyte cells model, respectively. However, the facts need to be validated by further studies both in vitro and in vivo.

並列關鍵字

Coumestrol ； Daidzein ； Astrocyte

參考文獻

曹善文 (2005) 特殊植化物對於人類單核球細胞株(THP-1)在LPS刺激下之功能性基因組研究,國立台灣大學植物研究所碩士論文.

林鈺珊 (2007) 二羥基異黃酮對星狀神經膠細胞的抗發炎作用,台北醫學大學藥學系碩士論文.

Adachi T, Ono Y, Koh K B, Takashima K, Tainaka H, Matsuno Y, Nakagawa S, Todaka E, Sakurai K, Fukata H, Iguchi T, Komiyama M, Mori C (2004) Long-term alteration of gene expression without morphological change in testis after neonatal exposure to genistein in mice: toxicogenomic analysis using cDNA microarray. Food Chem Toxicol. 42(3): 445 - 452.

Alic N O, Docagne F, Lesne S, MacKenzie E T, Nouvelot A, Buisson A, Vivien D (2000) "Ischemia-induced interleukin-6 as a potential endogenous neuroprotective cytokine against NMDA receptor-mediated excitotoxicity in the brain. J Cereb Blood Flow Metab. 20(6): 956-66

) Donepezil-tacrine hybrid related derivatives as new dual binding site inhibitors of AChE. Bioorg Med Chem. 13(24): 6588-6597.