- 學位論文
大蒜精油及二烯丙基二硫之類抗憂鬱效果在大鼠不可預期慢性溫和壓力模式中透過調節腦部NLRP3發炎體途徑和對腸道屏障及腸道菌相之影響
Antidepressant-like Effects of Garlic Essential Oil and Diallyl Disulfide in Unpredictable Chronic Mild Stress Rat Model through Mediating Brain NLRP3 Inflammasome Pathway and Influencing of Gut Barrier and Gut Microbiota
摘要
世界衛生組織統計全球約有3億人罹患憂鬱症，此疾病嚴重將造成患者自殺及帶來社會經濟上的重擔，現今研究已知壓力引起腦部中的發炎體蛋白3號 (NOD-, LRR- and pyrin domain-containing protein 3, NLRP3) 之活化，使得下游促發炎細胞激素 IL-1β 的累積，將導致慢性神經發炎；另外壓力造成腸道菌相組成及腸道屏障功能的改變使腸道菌產生之毒素如脂多醣可能得以進入血液循環系統中，造成周邊慢性發炎，此現象與部分憂鬱症患者血液檢測中，發現有較高發炎指標的濃度有相似性。目前臨床之抗憂鬱劑藥物常因副作用、作用發揮期過長和高復發率受到討論，故尋找其它具有類抗憂鬱之素材有其必要性。大蒜 (Allium sativum L.) 為多年生草本植物之地下鱗莖，除作為日常使用之辛香料外，草本綱目和文獻研究皆指出其具有解毒、消炎等功用，另外本實驗室先前於大鼠類憂鬱動物模式中，已發現大蒜精油介入後具有促進神經增生和調控單胺類物質代謝速率而具類抗憂鬱的效果。故本研究目的欲探討介入大蒜精油 (Garlic essential oil, GEO) 及其活性成分二烯丙基二硫化物 (Diallyl disulfide, DADS) 於大鼠不可預期慢性溫和壓力模式下是否透過上述途徑而能發揮類抗憂鬱功效，因而對其機制有更多面的了解。後續分析大鼠腦部神經傳導物質的代謝情形，探討腦部發炎體蛋白及腸通透道蛋白之表現量，並測定血清發炎指標之濃度及腸道菌相之變化情形。實驗以DADS 10 mg/kg bw及GEO 5、15、25 mg/kg bw分別介入，結果顯示大蒜精油能有效改善大鼠因壓力而減少對糖水偏好之程度 (p < 0.05)，且顯著降低腦部單胺類神經傳導物質升高的代謝速率 (p < 0.05)。分析腦部發炎體蛋白中NLRP3、ASC、Caspase-1與其下游IL-1β及腸道結構蛋白表現情形，結果發現在大蒜精油25 mg/kg bw介入後，可以顯著降低NLRP3發炎體蛋白及下游IL-1β之表現，在腸道通透蛋白則能回復其表現量及腸屏障功能，在血清中接受壓力之組別IL-1β及TNF-α濃度顯著增加，而在大蒜精油25 mg/kg bw介入的組別中能顯著減少其濃度 (p < 0.05)，顯示大蒜精油具有降低周邊系統發炎之效果，在腸道菌結果大蒜精油具有增加Ruminococcaceae的相對豐富度，此類菌群具有維持腸屏障的功能，此外也發現在壓力組別中Marvinbryantia菌屬數量的減少，與先前研究具有相似結果，綜合上述，大蒜精油藉由減緩大鼠腦部單胺類神經傳導物質的代謝速率、減少腦部NLRP3發炎體蛋白和下游IL-1β之表現，另外透過降低血清中發炎指標之濃度，增加腸道菌Ruminococcaceae豐富度回復腸屏障功能，達到類抗憂鬱之效果。
並列摘要
According to the statistics of the World Health Organization, about 300 million people worldwide suffer from depression. This disease will cause patients to commit suicide and bring social and economic burdens. Nowadays, it is known that stress causes the activation of NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3) causes the accumulation of the downstream proinflammatory cytokine IL-1β, which will lead to chronic neuroinflammation; in addition, the pressure causes changes gut microbiota composition and intestinal barrier function to make toxins such as lipopolysaccharide may enter the blood circulation system, causing chronic inflammation in the periphery. This phenomenon is similar to the concentration of high inflammation indicators found in serum of some depression patients. At present, clinical antidepressant drugs are argued by side effects, long duration of action and high recurrence rate, so it is necessary to search new antidepressant-like compounds. Garlic (Allium sativum L.) is an underground bulb of a perennial herb. In addition to being a spice for daily use, literature studies have pointed out that it has detoxification and anti-inflammatory functions. In addition, our laboratory preliminary results showed that garlic essential oil was found to have anti-depressive effects by promoting nerve proliferation and regulating the turnover rate of monoamines in depressive-like animal model. Therefore, the purpose of this study is to investigate whether gavage of garlic essential oil (GEO) and its active compound diallyl disulfide (DADS) in rats can be expected through the above-mentioned mechanisms under unpredictable chronic mild stress model to learn more about its anti-depression effects. Analysis of the turnover rate of neurotransmitters in the brain of rat, to explore the expression of inflammasome protein in the brain and intestinal permeability protein, and to determine the concentration of serum inflammation indicators and changes gut microbiota composition. The experiment involved DADS 10 mg/kg bw and GEO 5, 15, 25 mg/kg bw, respectively. The results showed that GEO can effectively improve the reducing of the preference sucrose water in rats due to stress (p <0.05), and significantly reduce the brain increased turnover rate of monoamine neurotransmitters (p <0.05). Analysis of the expression of NLRP3, ASC, Caspase-1 and its downstream IL-1β and intestinal structural protein. In the inflammasome protein of the brain showed that after the intervention of GEO 25 mg/kg bw, it can significantly reduce the NLRP3 protein and downstream performance of IL-1β, the intestinal permeability protein can restore its expression level and intestinal barrier function, and the concentration of IL-1β and TNF-α in serum significantly increased in stress group, while in GEO 25 mg/kg bw group can significantly reduce its concentration (p <0.05), showing that GEO has the effect of reducing inflammation in the peripheral system. In the gut microbiota, GEO has increased the relative abundance of Ruminococcaceae. In addition, it is also found that the number of Marvinbryantia bacteria in the stress group is reduced, which has similar results to previous studies. Based on the above, GEO reduces the turnover rate of neurotransmitters in the brain, the performance of NLRP3 inflammasome protein and downstream IL-1β, in addition, by reducing the concentration of inflammation indicators in the serum, increasing the abundance of intestinal bacteria Ruminococcaceae to restore intestinal barrier function, to achieve anti-depressant effects.
參考文獻
延伸閱讀
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