肺泡巨噬細胞在低氧狀態下分泌內皮素與其相關激素/趨化素之研究

Decreased ambient oxygen tension alters the expression of endothelin-1 and its associated cytokines/chemokines from alveolar macrophage

陳怡真(I-Chen Chen)

指導教授 ： 戴任恭

高雄醫學大學/醫學院/醫學研究所/碩士(2012年)

https://doi.org/10.6832/KMU.2012.00022

摘要

目的與假設: 肺泡巨噬細胞是呼吸的第一道防線，在許多人體與動物實驗證實，缺氧的肺泡巨噬細胞會產生導致全身發炎症狀的物質。內皮素(endothelin-1，ET-1)，原為一強力血管收縮素，也被證實與發炎反應有關。本研究主要探討在低氧情況下，肺泡巨噬細胞會增加內皮素表現量，並找出其他相關低氧的激素/趨化素的變化。
材料與方法: 鼠肺泡巨噬細胞(alveolar macrophage; NR8383)經過不同時間的低氧(1%O2)刺激後，利用微陣列基因表現晶片分析，發現ET-1在不同長度的低氧刺激都有明顯的上升，因此選定ET-1為研究標的，測定其經低氧刺激下在細胞的表現情形。此外，一氧化碳合成酶(iNOS)、亞硝酸鹽(NOx)、monocyte chemoattractant protein-1(MCP-1)、 tumor necrosis factor (TNF)、interleukin-11 (IL-11)，及細胞內cyclic GMP (cGMP) 與hypoxia-inducible factor-1α (HIF-1α)之濃度也一併檢測。
結果: 肺泡巨噬細胞在低氧刺激後，ET-1無論在基因或是蛋白質濃度表現均有顯著上升的情形，同時伴隨著iNOS、cGMP與NOx的基因表現上升( p<0.05)。MCP-1基因表現量在低氧8小時有上升，之後恢復正常。相反地，TNF、IL-11與HIF-1α在12小時內並未隨著低氧的刺激而有所變化。
結論: 本篇研究結果顯示肺泡巨噬細胞在低氧刺激下會增加ET-1的表現量。而一連串內皮素相關的激素與趨化素的變化，可提供肺臟因缺氧造成傷害的機轉與治療方向。

關鍵字

低氧 ； 發炎 ； 肺泡巨噬細胞 ； 微陣列 ； 內皮素

並列摘要

Purpose
Systemic inflammation induced by hypoxic alveolar macrophage has been documented in human and animal experiments. Endothelin-1 (ET-1), a potent vasoconstrictive peptide, has been proven its role in inflammation in mononuclear cells. The aim of the investigation was to assess whether hypoxia induces the production of endothelin-1 (ET-1) and other associated cytokines and chemokines in rat alveolar macrophages.
Materials and Methods
Rat alveolar macrophages were cultured at different times under hypoxia (1 % O2) or normoxic conditions (21% O2). We surveyed the RNA expression profile with microarray gene chips (Rat Whole Genome OneArray®,Phalanx Biotech Group, Inc.). Subsequently, accumulations of ET-1, inducible nitric oxide synthases (iNOS), NOx, cGMP and other cytokines/chemokines including monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor (TNF), interleukine-11(IL-11), hypoxia-inducible factor 1α (HIF-1α) were measured.
Results
ET-1, iNOS, NOx, and cGMP were significantly increased in the alveolar macrophage after hypoxia for 4 hours (all p<0.05). MCP-1 mRNA was increased at 8 hours and then recovered at 12 hours. There were no differences in TNF、IL-11 and HIF-1α in the first 12 hours under hypoxia stimulation.
Conclusion
This study indicated that hypoxia induces the synthesis of ET-1 in rat alveolar macrophages. The serial change of ET-1, iNOs, NO/cGMP pathway makes us more understand the mechanism of hypoxic injury in the lung.

並列關鍵字

hypoxia ； inflammation ； alveolar macrophage ； microarray ； endothelin

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