發酵諾麗果萃取物對於胃腸道保護之功效

Gastrointestinal Protection of Fermented Noni Fruit Extracts

黃信綸(Hsin-Lun Huang)

指導教授 ： 王進崑

中山醫學大學/健康管理學院/營養學研究所/博士(2015年)

https://doi.org/10.6834/CSMU.2015.00008

摘要

病原菌感染與其引起之發炎反應會提高罹患胃腸道疾病的風險，如常見的胃潰瘍與發炎性腸炎等。因此，如何避免或緩解細菌感染與相關之發炎反應是降低罹患胃腸道疾病的最佳策略。過去的研究已證實諾麗 (Morinda citrifolia)可以提良好的抗菌、抗發炎以及抗氧化能力。然而，諾麗果實對於胃腸道的效用仍未被發掘。在本研究中，發酵諾麗果實分別以乙醇與乙酸乙酯萃取，並探討此兩種萃取物對於幽門螺旋桿菌 (H. pylori) 與其所誘導胃上皮細胞發炎反應，以及腸道細胞發炎反應之抑制效果。首先，評估發酵諾麗果實萃取物對於幽門螺旋桿菌之抑制與抗附著效果與其引起的發炎因子，包括環氧合酶 (COX-2)、誘導型一氧化氮合酶 (iNOS)、細胞界白素8 (IL-8)、前列腺素 (PGE2)、一氧化氮 (NO)、嗜中性球趨化以及細胞毒素相關基因蛋白A (CagA)之轉運作用。萃取物對於幽門螺旋桿菌相關的傷口治癒功能與濾泡毒素A (VacA)轉運作用之效應亦被詳加觀察。另一方面，此研究亦評估發酵諾麗果實萃取物之抗氧化能力，對於腸道菌以及對於細菌脂多醣 (LPS) 與細胞界白素1β (IL-1β) 引起腸細胞發炎訊號之影響。結果顯示，兩種萃取物皆能抑制幽門螺旋桿菌之附著作用，並截斷細胞CagA轉運以及其所引起之發炎訊號(IL-8與嗜中性球趨化)，更能抑制COX-2與PGE2濃度。唯只有乙酸乙酯萃取物能抑制iNOS與NO之表現。發酵諾麗果實萃取物亦能夠藉由阻斷VacA轉運與訊號傳遞，降低細胞色素C釋放，進而促進傷口治癒。在腸道保護作用中，乙醇萃取物能夠促進益生菌腸道菌之生長 (Lactobacillus and Bifidobacterium spp.)。而乙酸已酯萃取物能夠顯著抑制LPS引起的活性氧物質(ROS)之釋放。乙酸乙酯更能夠藉由抑制NF-κB路徑來有效減緩IL-1β與LPS所引起的發炎反應 (COX-2、PGE2、IL-8與嗜中性球趨化)。進而的分析萃取物多酚類與主要貢獻物後，顯示乙醇與乙酸乙酯萃取物含有多量的多酚類成分，兩者間的多酚類物質組成亦相當迴異。而主要的多酚類物質能夠顯著的抑制幽門螺旋桿菌之附著與緩解胃細胞與腸細胞之發炎反應。綜觀結果，發酵諾麗果實萃取物能夠有效的抑制幽門螺旋桿菌感染所引起的發炎反應與促進傷口治癒，更能夠避免腸細胞陷入發炎迴圈之泥淖，而多酚類成分在此胃腸到保護作用中扮演重要角色。

關鍵字

幽門螺旋桿菌 ； 諾麗果 ； 多酚 ； 抗附著 ； 發炎反應 ； 抗氧化 ； 益生菌

並列摘要

Pathogen infection and its related inflammation which increase the risk of gastrointestinal disease formation, including gastric ulcer and inflammatory bowel disease. To prevent and relieve bacterial infection or inflammatory response are optimal stratagem. Noni (Morinda citrifolia) is found to possess antibacteria, anti-inflammation and antioxidative activites, but its effects on gastrointestinal protection remain unknown. In this study, the ethanol and ethyl acetate extracts of fermented noni fruit were used to evaluate the prevention and alleviation on Helicobacter pylori (H. pylori) infection and inflammatory response on gastric (AGS) and colonic (Caco-2) cells respectively. The inhibitory and antiadhesion activity of both extracts on H. pylori were evaluated. The pro-inflammatory molecules, namely cyclooxygenase (COX-2), inducible nitric oxide synthase (iNOS), interleukin-8 (IL-8), prostaglandin E2 (PGE2), nitric oxide (NO), transportation of cytotoxin associated gene A (CagA) protein and neutrophils migration were assessed after H. pylori treated in AGS cells. The wound healing and transportation of vacuolating toxin A (VacA) were estimated after H. pylori or bacterial-cultured medium treated. The inflammatory protein also be determined after lipopolysaccharide (LPS) and IL-1β treated on Caco-2 cells. Moreover, the antioxidation of both extracts on various free radicals and low-density lipoprotein (LDL) oxidation were evaluated. First, both extracts of fermented noni fruit contained abundant quercetin and coumaric acid respectively. Both extracts showed significant suppression on H. pylori adhesion, CagA transportation, inflammatory response (COX-2, iNOS, PGE2, NO), neutrophils migration and contribute to wound healing by impeding VacA signals although no inhibition on H. pylori growth. Both extract showed great antioxidative activities (trolox equivalent antioxidant capacity, reduction ability, ferrous ion chelating and LDL oxidation) and scavenging on free radicals (DPPH, superoxide anions and hydrogen peroxide), the ethyl acetate significantly suppressed the levels of intercellular reactive oxygen species (ROS) during LPS treated on Caco-2 cells. The ethanol extract promoted probiotics growth (Lactobacillus and Bifidobacterium spp.). On the contrary, the ethyl acetate extract can significantly inhibit inflammatory signals by NF-κB pathway without effecting on probiotic growth. The phenolic compounds of both extracts significantly inhibited H. pylori adhesion and inflammatory response on AGS and Caco-2 cells. In conclusion, the extracts of fermented noni fruit down-regulated inflammatory responses and promote wound healing during H. pylori infection. Ethyl acetate extract of fermented noni fruit can prevent excessive oxidation and inflammation on intestine. Phenolic compounds play key role on gastrointestinal protection.

並列關鍵字

Helicobacter pylori ； noni ； phenolics ； antiadhesion ； inflammation ； antioxidation ； probiotics

參考文獻

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