評估烏頭鹼及其衍生物在心臟功能的作用

The evaluation of cardiac effects of Aconitine and its derivatives

Widya Yanti Sihotang(Widya Yanti Sihotang)

指導教授 ： 葉竹來

高雄醫學大學/醫學院/醫學研究所碩士班/碩士(2019年)

摘要

許多的二萜生物鹼是存在於毛茛科的根莖類中之天然生物鹼，廣泛被使用於傳統中藥用以治療各種不同的疾病，例如鎮痛、抗發炎、腸胃炎、風濕熱、心血管疾病以及抗腫瘤。已有評估生物鹼的幾種化合物毒性而其中發現烏頭鹼在大鼠心肌細胞H9c2中具有最強的毒性。但是，對於其衍生物毒性之研究卻很少或甚至不曾進行探討。確定治療成分中的烏頭鹼及其衍生物的毒性對於傳統中藥的利用上是非常重要的。
本實驗的研究目的為評估並比較烏頭鹼及其衍生物在心臟中的副作用。本實驗將評估烏頭鹼及其衍生物（Aco-1與Aco-2）在體外試驗（心肌細胞H9c2）、離體組織試驗與體內試驗（Wistar大鼠）之心肌作用。我們分析细胞存活力和乳酸脱氢脢的释放 24小时，细胞凋亡以及钙离子的释 72 小时放以评評估烏頭鹼及其衍生物 (Aco-1 與 Aco-2) 的心毒性影響。心毒性可藉由細胞活性降低、乳酸脫氫脢的釋放及細胞凋亡判定，其按毒性順序排名為：Aconitine > Aco-1 > Aco-2。
實驗再以離體試驗測定從 Wistar大鼠分離出的右與左心房，其發現處理烏頭鹼從 10-7 M至10-6 M 有顯著降低左心房的收縮且與此同時自發性的增加右心房的心跳率。但是，當處理Aco-1與Aco-2對於左心房收縮與右心房心跳率並沒有顯著性的變化。為證實這些化合物的作用，執行血液動力學的變化與評估 ECG ±1小时用以作為心血管風險之指標。其結果顯示烏頭鹼能顯著誘導血液動力學的變化（降低血壓以及增加心跳率）以及利用ECG 評估出心律不整。研究結果也發現給予Wistar 大鼠烏頭鹼會造成心因性休克與死亡。除此之外，Aco-1與Aco-2 會略為降低血壓與心率，意味著這兩種化合物均可能造成心臟副作用但相較於烏頭鹼低。其結果能夠以ECG評估來證明 Aco-1與Aco-2處理並沒有顯著的變化。
綜合以上結果發現烏頭鹼相較於其衍生物（Aco-1與Aco-2）對於心臟具有最強的副作用。這些結果在未來對於傳統中藥可提供合理使用之基礎，減少副作用並同時保有治療效果。Aco-1與Aco-2相較於烏頭鹼具有較低的毒性可用於未來作為與烏頭鹼相同的治療效果之藥物。

關鍵字：烏頭鹼、心肌作用、Wistar 大鼠、心律跟肌力作用、血液動力學變化

關鍵字

烏頭鹼 ； 心肌作用 ； Wistar 大鼠 ； 心律跟肌力作用 ； 血液動力學變化

並列摘要

Numerous diterpenoid alkaloids, the natural alkaloids obtained from the rhizome of aconitum plant which belongs to the Ranunculaceae family are popularly used as Traditional Chinese Medicine (TCM) to treat various diseases. Commonly they have been used as analgesic and anti-inflammatory agents, and for rheumatic fever and various cancers. Several compounds of alkaloids have been evaluated their toxicity and Aconitine, as one of the bioactive alkaloid obtained from aconitum plant was found to have higher toxicity in H9c2 cells. However, the activities of its derivatives are either poorly described or not studied at all. It is important to compare the therapeutic effect of Aconitine with its derivatives and their side effects for their efficacy in TCM.
The aim of the current study is to evaluate and to compare the side effects of Aconitine and its derivatives on cardiac function. This study report the evaluation of cardiac effects of Aconitine and its derivatives (Aco-1 and Aco-2) by in vitro (H9c2 myocardial cells), ex vivo and in vivo (Wistar rats) studies. We assayed cell viability and lactate dehydrogenase release for 72 hr, apoptosis and calcium release for 24 hr to evaluate cardiotoxicity effects of Aconitine and its derivatives (Aco-1 and Aco-2). We found the toxicity by decreasing cell viability, increasing lactate dehydrogenase release, apoptosis and calcium level which ranked as follows, in descending order: Aconitine > Aco-1 > Aco-2. Subsequently, we continued with ex vivo experimental isolated right and left atria of Wistar rats. It was found that Aconitine significantly decreased the contractility of the left heart atria and at the same time it spontaneously and irregularly increased the right atrial rate by 10-7 M to 10-6 M of Aconitine. However, there is no significant change of left atria contraction and right atrial rate after treatment with Aco-1 or Aco-2. To confirm the effect of these compounds, hemodynamic change and electrocardiogram (ECG) evaluation were performed ± 1 hr. The result showed that Aconitine significantly induced hemodynamic change (decreasing blood pressure and increased heart rate) and arrhythmia in ECG evaluation. The results also showed the cardiogenic shock effect and death on Wistar rat by administration of Aconitine. Aside of that, Aco-1 and Aco-2 slightly decreased the blood pressure and heart rate indicating that both of these compounds might have cardiac side effects on the heart but it were lower compared to Aconitine. These results were supported with ECG evaluation which did not significantly changed when treated with Aco-1 and Aco-2.
In conclusion, this study indicates that Aco-1 and Aco-2 have lower cardiac side effect in comparison with Aconitine. It also suggests that Aco-1 might have higher toxicity than Aco-2. A very important point for using the drug is that it holds therapeutic effects and reduces the side effects, hence Aco-1 and Aco-2 could be the promising compounds in the future as a drug with the same therapeutic effect as Aconitine.

Keywords: Aconitine, cardiac effects, apoptosis, hemodynamic change, H9c2 cell, Wistar rats

並列關鍵字

Aconitine ； cardiac effects ； apoptosis ； hemodynamic change ； H9c2 cell ； Wistar rats

參考文獻

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