Activation of p38 mitogen-activated protein kinase by lipopolysaccharide in human neutrophils requires nitric oxide-dependent cGMP accumulation
Activation of p38 mitogen-activated protein kinase by lipopolysaccharide in human neutrophils requires nitric oxide-dependent cGMP accumulation
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DOI：
10.1074/jbc.274.1.537
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发表时间：
1999-01-01
影响因子：
4.8
通讯作者：
Ye, RD
中科院分区：
文献类型：
--
作者：
Browning, DD;Windes, ND;Ye, RD
本研究探讨了脂多糖和甲酰肽刺激的人中性粒细胞p38磷酸化的信号转导途径(S)。用一氧化氮合酶抑制剂N-硝基-L-精氨酸甲酯或用一氧化氮合酶清除剂2-phenyl-tetramethylimidazoline-1-oxyl-3-oxide处理来阻断中性粒细胞中的一氧化氮(NO)途径，可减弱脂多糖对丝裂原活化蛋白激酶p38的磷酸化作用，但不影响甲硫氨酸-亮氨酸-苯丙氨酸。使用NO释放剂S-亚硝基-N-乙酰青霉胺和硝普钠，确定一氧化氮足以引起p38磷酸化增加。用磷酸二酯酶抑制剂增加细胞内cGMP，用YC-1刺激可溶性鸟苷酸环化酶，或用外源二丁酰cGMP刺激细胞内cGMP，导致有丝分裂原激活的蛋白激酶/细胞外信号调节激酶3，6(MEK3，6)激活和p38磷酸化，这种现象是MEK3，6所特有的，因为这些药物对MEK1.2的磷酸化状态没有影响。分别用特异性抑制剂KT5823和H89显示蛋白激酶G而不是蛋白激酶A在脂多糖下游的作用，而不是甲酰甲硫基亮氨酰苯丙氨酸的作用。这些结果表明，fMet-Leu-Phe和脂多糖激活p38涉及不同的机制，而通过NO依赖的鸟苷酸环化酶激活蛋白激酶G是脂多糖下游p38磷酸化的必要条件和充分条件。
This study examined the signal transduction pathway(s) leading to phosphorylation of p38 in human neutrophils stimulated with lipopolysaccharide and formyl peptides. Blockade of the nitric oxide (NO) pathway in neutrophils with the NO synthase inhibitor N-nitro-L-argnine methyl ester or by treatment with the NO scavenger 2-phenyl-tetramethylimidazoline-1-oxyl-3-oxide attenuated phosphorylation of the mitogen-activated protein kinase p38 in response to lipopolysaccharide but not fMet-Leu-Phe. Using the NO releasing agents S-nitroso-N-acetylpenicillamine and sodium nitroprusside it was determined that nitric oxide is sufficient to cause an increase in phosphorylation of p38. Increasing cellular cGMP with phosphodiesterase inhibitors, by stimulation of soluble guanylyl cyclase with YC-1 or with exogenous dibutyryl cGMP resulted in mitogen-activated protein kinase/extracellular signal-regulated kinase kinase 3,6 (MEK3,6) activation and phosphorylation of p38, This phenomenon was specific for MEK3,6, because these agents had no effect on the phosphorylation state of MEK1.2. A role for protein kinase G but not protein kinase A downstream of lipopolysaccharide but not formylmethionylleucylphenylalanine was shown using the specific inhibitors KT5823 and H89, respectively. These data indicate that activation of p38 by fMet-Leu-Phe and lipopolysaccharide involve different mechanisms, and that activation of protein kinase G by NO-dependent stimulation of guanylyl cyclase is necessary and sufficient for phosphorylation of p38 downstream of lipopolysaccharide.