以蛋白質體學探討天麻水萃物抗憂鬱之功效

Abstract

憂鬱症為全球最嚴重的精神疾病之一，其中重鬱症（Major depressive disorder, MDD）更會造成人類的失能，世界衛生組織（World Health Organization, WHO）預測MDD將於2030年成為全球失能疾病第一名。然而，現行治療憂鬱症的藥物經常帶來許多副作用，因此，發展預防憂鬱症或其替代療法則為一重要課題。天麻（Gastodia elata blume, GE）為用於安神寧腦的傳統中藥材，過去研究證實天麻具有神經保護、抗癲癇與抗憂鬱的功效。本研究以強迫游泳試驗（forced swimming test, FST）誘發大鼠類憂鬱症後，利用糖水攝取試驗（sucrose consumption test, SCT）了解經FST誘發後大鼠是否具有快樂感降低的症狀（anhedonia），並利用二維膠體電泳與膠片分析軟體探討經天麻水萃物（water extract of Gastrodia elata blume, WGE）給予後，大鼠大腦組織（額葉皮質、海馬迴與紋狀體）中蛋白質層面的變化，搭配質譜儀與蛋白質身份資料庫（Uniprot）鑑定蛋白質身份，再以系統生物資訊軟體（Metacore™）與資料庫配對探討天麻水萃物抗憂鬱的可能機制路徑，最後利用西方墨點法（Western blotting）驗證系統生物資訊軟體的結果。結果顯示，經過FST的大鼠，其糖水攝取量顯著較正常組與其前兩週低，顯示FST確實會引起快樂感降低的症狀。蛋白質體學結果發現，於額葉皮質（frontal cortex）、海馬迴（hippocampus）與紋狀體（striatum）分別有43、68與23個蛋白質具有顯著差異，進一步以質譜儀鑑定與資料庫比對，額葉皮質與海馬迴各有30與43個蛋白質身份被鑑定。在系統資訊軟體配對結果顯示，天麻水萃物抗憂鬱的機制可能與Slit-Robo pathway、neuronal cytoskeleton remodeling相關。西方墨點法的結果顯示，給予天麻水萃物後，額葉皮質的Slit-1、Slit-2、RhoA有顯著下降，CRMP-2、profilin-1有顯著增加，在海馬迴中Slit-1、RhoA有顯著下降，CRMP-2與 profilin-1有顯著增加，此與二維膠體電泳、系統生物資訊軟體的結果相符。綜合以上結果，天麻水萃物可能是透過Slit-Robo pathway機制或neuronal cytoskeleton remodeling 並增加神經可塑性而達抗憂鬱的效果。

Major depression disorder (MDD) is one of the most serious psychological diseases in the world and as per a WHO report of 2004, it will become to the first leading disability disease in the world in year 2030. However, the therapies for MDD still cause many side effects. Hence it is imperative to look for an alternative preventive remedy. In our previous study, we have discovered that the water extract of Gastrodia elata Blume (WGE) significantly decreased the immobility time of rats in forced swimming test (FST) and modulated the amounts of neurotransmitters. To further elucidate the antidepressant mechanisms of WGE, we performed two dimensional electrophoresis. The data were integrated to identify the potential antidepressant pathways. The data were integrated to identify the potential antidepressant pathways. In the expression levels we have found that 43 spots in the frontal cortex, 68 spots in the hippocampus and 23 spots in striatum are significantly different between the WGE and negative control groups. Further, the proteomics results were validated by western blotting. Slit-Robo pathway and neuronal cytoskeleton remodeling were matched by Metacore™, the knowledge database and pathway analysis software. These pathways regulate the neuroplasticity which is one of the depression pathological hypotheses. The expression of Slits, CRMP-2, RhoA and profilin-1 is significantly different between negative control and WGE groups in frontal cortex and hippocampus by Western blotting. These are match to the results of 2-DE and bioinformatics software. In conclusion, Slit-Robo pathway neuronal cytoskeleton remodeling may be the antidepressant mechanism of Gastrodia elata Blume.