白藜蘆醇減緩斑馬魚傷口引發發炎之作用機制   全文下載

Resveratrol Treatment Attenuates the Wound-Induced Inflammation in Zebrafish Larvae through the Suppression of Myeloperoxidase Expression

白藜蘆醇（resveratrol）是一種存在於許多植物中的多酚類植物抗毒素，先前研究指出白藜蘆醇具有抗發炎的效果，但其分子機制仍不完全清楚。本研究旨在以傷口引發發炎反應之斑馬魚為模式生物，探討白藜蘆醇在生物活體中之抗發炎作用機制。首先將尾鰭受傷之斑馬魚幼魚以白藜蘆醇治療八小時，利用以綠色螢光蛋白（green fluorescent protein, gFP）專一標記嗜中性白血球中特有之骨髓過氧化?（myeloperoxidase, mpx）的基因轉殖魚tg（mpx：gFP），觀察活體中嗜中性白血球之聚集，再以組織化學染色檢測骨髓過氧化?之活性，並以即時定量聚合?連鎖反應（real-time PCR）評估骨髓過氧化?及環氧合?-2（cyclooxygenase-2, cox-2）之基因表現。結果顯示，白藜蘆醇不影響斑馬魚傷口引發之嗜中性白血球聚集；白藜蘆醇明顯抑制傷口引發骨髓過氧化?之活性，且此抑制效果與白藜蘆醇之劑量呈正相關；此外，白藜蘆醇導致骨髓過氧化?及環氧合?-2之基因表現顯著降低。綜上所述，白藜蘆醇在斑馬魚活體中對傷口引發發炎反應之抗發炎作用機制，是透過抑制骨髓過氧化?及環氧合?-2之表現，而非抑制嗜中性白血球之聚集；此外，此斑馬魚傷口發炎模式，也可作為篩選其他可能抗發炎化合物之活體生物篩選平台。"

Resveratrol, a polyphenolic phytoalexin found in many plants, was reported to exhibit anti-inflammatory effects, but its molecular mechanism is not fully understood. This study was aimed to investigate the anti-inflammatory effects of resveratrol in vivo using a zebrafish model of wound-induced inflammation. Caudal fin-wounded zebrafish larvae were treated with resveratrol for 8 h. Neutro-phil recruitment was visualized in transgenic line “Tg (mpx：GFP)” expressing GFP-tagged neutrophil-specific myeloperoxidase (mpx). The enzymatic activity of Mpx was evaluated by histochemical staining. Relative mRNA levels of mpx and cyclooxegenase-2 (cox2) were quantified by qRT-PCR, and the protein expression levels of Mpx and Cox2 were detected by immunostaining. Results showed that wound-induced neutrophil recruitment in zebrafish was not affected by resveratrol, but Mpx enzymatic activity in zebrafish was significantly suppressed by resveratrol in a dose-dependent manner. Moreover, both mRNA and protein expression levels of Mpx and Cox2 were significantly down-regulated by resveratrol. Taken together, our results provide in vivo evidence that the anti-inflammatory effects of resveratrol on wound-induced inflammation are significantly mediated through the suppression of Mpx and Cox2 at both transcriptional and protein levels, rather than the down-regulation of neutrophil recruitment. In conclusion, this in vivo zebrafish model can be readily applied to screen other potential anti-inflammatory compounds at a whole-organism level.