Antoine Francis, Girard Denis
Laboratoire de recherche en inflammation et physiologie des granulocytes, INRS-Institut Armand-Frappier, University of Québec , Laval, Quebec , Canada.
J Immunotoxicol. 2015 Apr-Jun;12(2):188-93. doi: 10.3109/1547691X.2014.917749. Epub 2014 Jun 13.
Curcumin has been found to possess anti-inflammatory activities and neutrophils, key players in inflammation, were previously found to be important targets to curcumin in a few studies. For example, curcumin was found to induce apoptosis in neutrophils by a p38 mitogen-activated protein kinase (MAPK)-dependent mechanism. However, the role of curcumin on the biology of neutrophils is still poorly defined. To study the role of curcumin on neutrophil degranulation and to determine the role of p38 MAPK, human neutrophils were freshly isolated from healthy individuals and incubated in vitro with curcumin. Degranulation was studied at three levels: surface expression of granule markers by flow cytometry; release of matrix metallopeptidase-9 (MMP-9 or gelatinase B) enzyme into supernatants by Western blot; and gelatinase B activity by zymography. Activation of p38 MAPK was studied by monitoring its tyrosine phosphorylation levels by western blot and its role by the utilization of a pharmacological inhibitor. The results indicate that curcumin increased the cell surface expression of CD35 (secretory vesicle), CD63 (azurophilic granules), and CD66b (gelatinase granules) in neutrophils. Also, curcumin increased the release and enzymatic activity of gelatinase B in the extracellular milieu and activated p38 MAP kinase in these cells. However, in contrast to fMLP, curcumin-induced enzymatic activity and secretion of gelatinase B were not reversed by use of a p38 inhibitor. Finally, it was found that curcumin was able to enhance phagocytosis. Taken together, the results here demonstrate that curcumin induced degranulation in human neutrophils and that the increased gelatinase activity is not dependent on p38 MAPK activation. Therefore, degranulation is another human neutrophil function that could be modulated by curcumin, as well as phagocytosis.
姜黄素已被发现具有抗炎活性，而中性粒细胞作为炎症中的关键参与者，在一些研究中被发现是姜黄素的重要作用靶点。例如，研究发现姜黄素通过p38丝裂原活化蛋白激酶（MAPK）依赖性机制诱导中性粒细胞凋亡。然而，姜黄素在中性粒细胞生物学中的作用仍未明确界定。为了研究姜黄素对中性粒细胞脱颗粒的作用并确定p38 MAPK的作用，从健康个体中新鲜分离出人中性粒细胞，并在体外与姜黄素一起孵育。在三个水平上研究脱颗粒：通过流式细胞术检测颗粒标志物的表面表达；通过蛋白质印迹法检测基质金属肽酶-9（MMP-9或明胶酶B）酶释放到上清液中；通过酶谱法检测明胶酶B活性。通过蛋白质印迹法监测其酪氨酸磷酸化水平来研究p38 MAPK的激活，并利用药理学抑制剂研究其作用。结果表明，姜黄素增加了中性粒细胞中CD35（分泌囊泡）、CD63（嗜天青颗粒）和CD66b（明胶酶颗粒）的细胞表面表达。此外，姜黄素增加了细胞外环境中明胶酶B的释放和酶活性，并激活了这些细胞中的p38 MAP激酶。然而，与fMLP不同，使用p38抑制剂并不能逆转姜黄素诱导的明胶酶B的酶活性和分泌。最后，发现姜黄素能够增强吞噬作用。综上所述，这里的结果表明姜黄素诱导人中性粒细胞脱颗粒，并且增加的明胶酶活性不依赖于p38 MAPK激活。因此，脱颗粒是另一种可被姜黄素调节的人中性粒细胞功能，吞噬作用也是如此。
