作者机构:
[Yu, Xiaohua; Zhao, Guojun; Yin, Kai; Li, Xiaoxu; Tang, Chaoke; Jiang, Zhisheng; Xiao, Ji; Mo, Zhongcheng] Univ S China, Inst Cardiovasc Res, Key Lab Atherosclerol Hunan Prov, Life Sci Res Ctr, Hengyang 421001, Peoples R China.;[Yu, Xiaohua] Univ S China, Sch Nursing, Hengyang 421001, Peoples R China.;[Fu, Yuchang] Univ Alabama Birmingham, Dept Nutr Sci, Birmingham, AL 35294 USA.;[Zha, Xiaohui] Univ Ottawa, Ottawa Hosp, Res Inst, Ottawa, ON K1H 8L6, Canada.
通讯机构:
[Tang, Chaoke] U;Univ S China, Inst Cardiovasc Res, Key Lab Atherosclerol Hunan Prov, Life Sci Res Ctr, Hengyang 421001, Peoples R China.
关键词:
Niemann–Pick type C1;oxLDL;ERK1/2;COX-2;PPARα;cholesterol
摘要:
The Niemann–Pick type C1 (NPC1) is located mainly in the membranes of the late endosome/lysosome and controls the intracellular cholesterol trafficking from the late endosome/lysosome to the plasma membrane. It has been reported that oxidized low-density lipoprotein (oxLDL) can up-regulate NPC1 expression. However, the detailed mechanisms are not fully understood. In this study, we investigated the effect of oxLDL stimulation on NPC1 expression in THP-1 macrophages. Our results showed that oxLDL up-regulated NPC1 expression at both mRNA and protein levels in a dose-dependent and time-dependent manner. In addition, oxLDL also induced the phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2). Treatment with oxLDL significantly increased cyclooxygenase-2 (COX-2) mRNA and protein expression in the macrophages, and these increases were suppressed by the ERK1/2 inhibitor PD98059 or ERK1/2 small interfering RNA (siRNA) treatment. OxLDL up-regulated the expression of peroxisome proliferator-activated receptor α (PPARα) at the mRNA and protein levels, which could be abolished by COX-2 siRNA or COX-2 inhibitor NS398 treatment in these macrophages. OxLDL dramatically elevated cellular cholesterol efflux, which was abrogated by inhibiting ERK1/2 and/or COX-2. In addition, oxLDL-induced NPC1 expression and cellular cholesterol efflux were reversed by PPARα siRNA or GW6471, an antagonist of PPARα. Taken together, these results provide the evidence that oxLDL can up-regulate the expression of the NPC1 through ERK1/2/COX-2/PPARα-signaling pathway in macrophages.
摘要:
Background Macrophage migration inhibitory factor (MIF) is an upstream regulator in immune and inflammatory responses. However, its role in viral myocarditis remains unknown. In this study, we investigated the role of the MIF in coxsackievirus B3 (CVB3)-induced myocarditis. Methods Mice were randomized into two groups receiving either Eagle’s minimal essential medium (EMEM, control group) or virus solution (infected group). Subsets of mice in the infected group were sacrificed on days 3, 7, 14 and 28 after inoculation. Expression of MIF was detected using an enzyme-linked immunosorbent assay (ELISA), reverse transcription polymerase chain reaction and immunohistochemistry. A neutralizing antibody (Ab) to MIF was injected intraperitoneally from day 0 to 7 after inoculation. Disease severity was estimated by histopathology of the heart and by the heart weight to body weight ratio, and the interleukin-1β (IL-1β) and tumor necrosis factor α (TNF-α) in the myocardium were measured by ELISA on day 14. Results The serum MIF concentration and expression levels of myocardial MIF mRNA and protein were significantly elevated in mice on days 7 and 14 post-infection. The survival rate was markedly higher and disease severity was obviously less in mice treated with anti-MIF Ab. Furthermore, MIF blockade significantly decreased the IL-1β and TNF-α in the myocarditic heart. Conclusion These results demonstrate that MIF is an important naturally occurring inflammatory cytokine in CVB3-induced myocarditis, and anti-MIF Ab may lessen the inflammatory response.
摘要:
目的探讨应用过渡期护理模式(Transitional Care Model,TCM)对慢性阻塞性肺疾病(COPD)出院患者自我护理行为的影响。方法以TCM为依据,对40例COPD出院患者进行4个月的护理干预。出院前3d及干预后4个月,采用COPD患者自我护理行为问卷评估患者的自我护理行为状况。结果干预后,COPD患者自我护理行为及各维度得分均高于干预前,差异具有统计学意义(P<0.01)。结论运用TCM为COPD出院患者提供过渡期护理,有利于提高患者的自我护理能力。