Yin Wen, Yang Jian-hong, Hu Xiao-min, Yuan Jing, Luo Yan-jun, Li Yue-cai
Department of Emergency, Xijing Hospital, The Fourth Military Medical University, Xi'an 710032, Shanxi, China.
Zhongguo Wei Zhong Bing Ji Jiu Yi Xue. 2003 Jul;15(7):429-31.
To investigate effects of polymixin B (PMB) on I-kappaB kinase(IKK-beta), inhibitor protein(IkappaB-alpha) and nuclear factor-kappa B(NF-kappaB) in lipopolysaccharide(LPS)-induced pulmonary alveolar macrophages (PAM), and explore the anti-inflammatory mechanism of PMB.
PAM from rats collected by bronchoalveolar lavage was cultured and divided into three groups. In the control group, PAM was not stimulated with LPS and not treated with PMB. In the LPS stimulated group, PAM was stimulated with LPS. In the PMB treated group, PAM was pretreated with PMB half an hour prior to LPS stimulation. The expression of IKK-beta mRNA, level of IkappaB-alpha and the activity of NF-kappaB in PAM were measured by in situ hybridization(ISH), enzyme linked immunoadsorbent assay (ELISA) and electrophoretic mobility shift assay(EMSA), respectively.
In the LPS stimulated group, the expression of IKK-beta mRNA (0.147+/-0.015) and activity of NF-kappaB (0.828+/-0.019) in PAM significantly increased, whereas levels of IkappaB-alpha (0.228+/-0.021) decreased (all P<0.01) in PMB treated groups. The expression of IKK-beta mRNA (0.112+/-0.022) and activity of NF-kappaB (0.358+/-0.011) were down-regulated while level of IkappaB-alpha (0.477+/-0.016) was up-regulated(P<0.01).
LPS might induce expression of IKK-beta mRNA, degradation of IkappaB-alpha and activation of NF-kappaB PMB could inhibit the expression of IKK-beta, degradation of IkappaB-alpha and activation of NF-kappaB, showing marked anti-inflammatory property.
研究多黏菌素B（PMB）对脂多糖（LPS）诱导的肺泡巨噬细胞（PAM）中I-κB激酶（IKK-β）、抑制蛋白（IκB-α）和核因子-κB（NF-κB）的影响，探讨PMB的抗炎机制。
通过支气管肺泡灌洗收集大鼠的PAM并进行培养，分为三组。对照组PAM不接受LPS刺激且不进行PMB处理。LPS刺激组PAM接受LPS刺激。PMB处理组PAM在LPS刺激前半小时用PMB预处理。分别采用原位杂交（ISH）、酶联免疫吸附测定（ELISA）和电泳迁移率变动分析（EMSA）检测PAM中IKK-β mRNA的表达、IκB-α的水平和NF-κB的活性。
在LPS刺激组中，PAM中IKK-β mRNA的表达（0.147±0.015）和NF-κB的活性（0.828±0.019）显著增加，而IκB-α的水平（0.228±0.021）降低（均P<0.01）。在PMB处理组中，IKK-β mRNA的表达（0.112±0.022）和NF-κB的活性（0.358±0.011）下调，而IκB-α的水平（0.477±0.016）上调（P<0.01）。
LPS可能诱导IKK-β mRNA的表达、IκB-α的降解和NF-κB的激活，PMB可抑制IKK-β的表达、IκB-α的降解和NF-κB的激活，显示出显著的抗炎特性。
