Objective To investigate the role of c-Jun N-terminal kinase (JNK) signal transduction pathway on the up-regulation of the expression of acyl-coenzyme A: cholesterol acyltransferasel (ACAT1) induced by Chlamydia pneumoniae (C. pn), and to discuss the mechanism of macrophages-derived foam cell formation induced by C. pn. Methods C. pn was propagated in Hep-2 cells. THP-1 monocytes were induced into macrophages by 160 nmol/L phorbol myristate acetate(PMA) for 48 h, and were randomly allocated into four groups to be incubated continually: control group, C. pn infection group, C. pn and SP600125 (a special JNK inhibitor)group and SP600125 group. Lipid droplets in cytoplasm were observed by oil red O staining. The contents of intracellular cholesterol ester were detected by enzyme fluorescence analysis. The expressions of ACAT1 mRNA and protein were determined by reverse transcriptase polymerase chain reaction(RT-PCR) and Western blot, respectively. Results Compared with the control group, the expressions of ACAT1 mRNA and protein were up-regulated in C. pn infection group [(4.16±0.26) vs. (2.17±0.18), (1.20±0.10)vs. (0.61±0.03), both P<0.05], and C. pn-induced foam cell formation was observed. The expressions of ACAT1 mRNA and protein and the foam cell formation were inhibited by SP600125 in a concentration-dependent manner (r = - 0.92, P<0.05; r= - 0. 96, P<0.05, respectively). Conclusions The up-regulation of ACAT1 expression is induced by C. pn via JNK signal transduction pathway, which is involved in the mechanism of C. pn-induced macrophage-derived foam cell formation.

AIM: To investigate the signal transduction mechanism of Chlamydia pneumoniae (Cpn) in down-regulating the expression of ATP binding cassette A1 (ABCA1) and ATP binding cassette G1 (ABCG1),the key molecules in cholesterol efflux and atherogenesis,from THP-1-derived macrophages. METHODS: Cpn was propagated in Hep-2 cells. THP-1 monocytes were induced into macrophages by 160 nmol/L phorbol myristate acetate (PMA) for 48 h,and were randomly allocated into 4 groups to incubate continually: control group,50 mg/L low density lipoprotein (LDL); Cpn infection group,Cpn (1×10~6 IFU) and 50 mg/L LDL; Cpn and SP600125 (a special JNK inhibiter) group,THP-1 macrophages were previously treated with different concentrations (1-20 μmol/L) of SP600125 for 1 h,and then infected with Cpn (1×10~6 IFU) and 50 mg/L LDL; SP600125 group,SP600125(20 μmol/L)and 50 mg/L LDL. The expressions of ABCA1/ABCG1 and peroxisome proliferator-activated receptor γ (PPARγ) from each group were detected then. The cholesterol efflux was detected by enzyme-fluorescence. The expressions of ABCA1/ABCG1 and PPARγ mRNA and protein were determined by RT-PCR and Western blotting,respectively. RESULTS: Cpn not only down-regulated the ABCA1/ABCG1 expression,but also down-regulated the expression of PPARγ,which regulated the ABCA1/ABCG1 genes transcriptions. However,the mentioned effects of Cpn infection were restrained by the special JNK inhibitor SP600125 in a dose-dependent manner. CONCLUSION: Chlamydia pneumoniae may down-regulate ABCA1/ABCG1 expression from THP-1-derived macrophages via JNK-PPARγ signal transduction pathway.

Objective:To investigate the effects of Chlamydia pneumoniae(Cpn) on SR-A1 and CD36 expression in THP-1-derived macrophages and role of c-Jun NH_2-terminal signal transduction pathway in the process.Methods:Cpn was propagated in Hep-2 cells.THP-1 monocytes were induced into macrophages by 160 nmol/L phorbol myristate acetate(PMA)for 48h,and were randomly allocated into four groups to be incubated continually: control group;Cpn infection group;Cpn and SP600125(a JNK inhibiter)group and SP600125 group.Lipid droplets in cytoplasm were observed by oil red O staining.The contents of intracellular cholesterol ester were detected by enzyme-fluorescence.The expression of SR-A1 and CD36mRNA and protein were determined by RT-PCR and Western blot, respectively. Results:THP-1-derived macrophages infected with Cpn resulted in large accumulation of lipid droplets and foam cell formation when co-cultured with LDL.Meanwhile,the expression of SR-A1 mRNA and protein were up-regulated by Cpn infection (P<0.05).However,the expressions of CD36 mRNA and protein in THP-1-derived macrophages infected with Cpn were unchanged.Moreover,the up-regulation of SR-A1 and foam cell formation induced by Cpn could be restrained by the JNK inhibiter SP600125 in a dose-dependent manner,and SP600125 had little impact on the expression of CD36 in THP-1-derived macrophages infected with Cpn.Conclusion:The up-regulation of SR-A1 but not CD36 expression is involved in mechanisms of Cpn inducing foam cell formation.And Chlamydia pneumoniae up-regulates the expression of SR-A1 via the JNK signal transduction pathway.This may be a novel mechanism for the foam cell formation induced by Cpn.

Objective To understand the status of knowledge and attitude of schistosomiasis control among the human populafion in schistosomiasis transmission-controlled area of Changqiu mountainous areas.Methods The subjects were selected by the random cluster sampling method among residents and students in these alias,then they were investigated by questionnaire.Resuits A total of 150 residents and 209 students were selected.There were 60% of the residents whose awareness rates of the knowledge on schistosomiasis control were above 90%.The correction rates of the questions in residents were between 99.30% and 100%.and the awareness rates about the questionswhether re-infection would occure after schistosomiasis was cured and the remedy for schistosomiasisof female adults were both 75.40%.The correction rates of the two question8 on attitude and behaviour of schistosomiasis control in adults were above 80.00%.In students'questionnaires.the awareness rates of knowledge on schistosomiasis control were above 90%.except the two questions on the shape of the snailand the infection-risk months of schistosomiasis.The correction rates of attitude and behaviour of schistosomiasis control were aslo above 80%.Conclusion The correction rates of knowledge,attitude and behaviour of schistosomiasis control of adults and students have reached the national goal of schistosomiasis control in 2008.