Singhal Pravin C, Bhaskaran Madhu, Patel Jaimita, Patel Kalpesh, Kasinath Balakuntalam S, Duraisamy Senthil, Franki Nicholas, Reddy Krishna, Kapasi Aditi A
Immunology and Inflammation Center, North Shore-Long Island Jewish Research Institute and Division of Kidney Diseases and Hypertension, Long Island Jewish Medical Center, New Hyde Park, NY 11040, USA.
J Immunol. 2002 Apr 15;168(8):4025-33. doi: 10.4049/jimmunol.168.8.4025.
In this study, we evaluated the molecular mechanisms involved in morphine-induced macrophage apoptosis. Both morphine and TGF-beta promoted P38 mitogen-activated protein kinase (MAPK) phosphorylation, and this phosphorylation was inhibited by SB 202190 as well as by SB 203580. Anti-TGF-beta Ab as well as naltrexone (an opiate receptor antagonist) inhibited morphine-induced macrophage P38 MAPK phosphorylation. Anti-TGF-beta Ab also attenuated morphine-induced p53 as well as inducible NO synthase expression; in contrast, N(G)-nitro-L-arginine methyl ester, an inhibitor of NO synthase, inhibited morphine-induced P38 MAPK phosphorylation and Bax expression. Morphine also enhanced the expression of both Fas and Fas ligand (FasL), whereas anti-FasL Ab prevented morphine-induced macrophage apoptosis. Moreover, naltrexone inhibited morphine-induced FasL expression. In addition, macrophages either deficient in FasL or lacking p53 showed resistance to the effect of morphine. Inhibitors of both caspase-8 and caspase-9 partially prevented the apoptotic effect of morphine on macrophages. In addition, caspase-3 inhibitor prevented morphine-induced macrophage apoptosis. These findings suggest that morphine-induced macrophage apoptosis proceeds through opiate receptors via P38 MAPK phosphorylation. Both TGF-beta and inducible NO synthase play an important role in morphine-induced downstream signaling, which seems to activate proteins involved in both extrinsic (Fas and FasL) and intrinsic (p53 and Bax) cell death pathways.
在本研究中，我们评估了吗啡诱导巨噬细胞凋亡所涉及的分子机制。吗啡和转化生长因子-β（TGF-β）均促进P38丝裂原活化蛋白激酶（MAPK）磷酸化，且SB 202190以及SB 203580可抑制这种磷酸化。抗TGF-β抗体以及纳曲酮（一种阿片受体拮抗剂）可抑制吗啡诱导的巨噬细胞P38 MAPK磷酸化。抗TGF-β抗体还可减弱吗啡诱导的p53以及诱导型一氧化氮合酶的表达；相反，一氧化氮合酶抑制剂N(G)-硝基-L-精氨酸甲酯可抑制吗啡诱导的P38 MAPK磷酸化和Bax表达。吗啡还增强了Fas和Fas配体（FasL）的表达，而抗FasL抗体可阻止吗啡诱导的巨噬细胞凋亡。此外，纳曲酮可抑制吗啡诱导的FasL表达。另外，FasL缺陷或缺乏p53的巨噬细胞对吗啡的作用具有抗性。半胱天冬酶-8和半胱天冬酶-9的抑制剂均可部分阻止吗啡对巨噬细胞的凋亡作用。此外，半胱天冬酶-3抑制剂可阻止吗啡诱导的巨噬细胞凋亡。这些发现表明，吗啡诱导的巨噬细胞凋亡通过阿片受体经P38 MAPK磷酸化进行。TGF-β和诱导型一氧化氮合酶在吗啡诱导的下游信号传导中均发挥重要作用，这似乎激活了参与外源性（Fas和FasL）和内源性（p53和Bax）细胞死亡途径的蛋白。
