2.Application of CRISPR/Cas9 system in virus research
Qingfen ZHENG ; Zhongping DUAN ; Jiansheng LI
Journal of Clinical Hepatology 2016;32(1):185-187
To date,the clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9 system has been widely used to edit the genome in many species and cells.The system is the third generation of artificial endonuclease,which can edit DNA by recognizing short DNA sequences.This paper reviews the structural features of the system and its application in virus research,such as the functional studies of virus-related genes and the exploration of antiviral therapies (including HIV,HBV,and EB virus),looking forward to the future direc-tion of virus research.
4.Effects of Stroke Unit on the Compliance of Secondary Prevention in Patients with Stroke
Zhongping AN ; Jialing WU ; Yuzhang JI ; Sha JIN ; Jiangang DUAN
International Journal of Cerebrovascular Diseases 2008;16(4):277-279
Objective: To investigate the impact of stroke unit (SU) on the compliance of secondary prevention in patients with stroke at 12 months after stroke. Methods: Research subjects were stroke patients who were treated in SU (n = 500) and in general ward (GW) (n =445) using a design of retrospective study. The patients in the SU group were followed up by hospital, telephone and home interviews for 12 months, and the patients in the GW group were followed up by telephone interview for 12 months. The main outcome measures were the rate of using antithrombotics, the rate of smoking cessation, and the rates of awareness of early stroke symptom and stroke risk factors of patients. Results: he rate of using antithrombotics was 92.76% in the SU group, and it was significantly higher than 51.49% in the GW group (P <0.01); the rate of smoking cessation, and the rates of awareness of early stroke symptom and stroke risk factors of patients were 82.33%, 91.04%, and 94.03% respectively in the SU group, and they were significantly higher than 54.75%, 6.53%, and 70.37% in the GW group(P all < 0.01 ). Conclusions: SU attaches importance to the secondary stroke prevention and emphasizes standardized treatment, and the compliance of the secondary stroke prevention in patient with stroke is improved significantly.
5.The protective role of peroxisome proliferator activated receptors-α and pathomechanism in D-galactosamine/lipopolysaccharide-induced acute liver failure in rats
Mingjing JIAO ; Feng REN ; Li ZHOU ; Zhongping DUAN ; Caiyan ZHAO
Chinese Journal of Internal Medicine 2014;53(9):730-734
Objective To determine the role and mechanism of peroxisome proliferator activated receptors (PPAR) α in a mouse model of D-galactosamine/lipopolysaccharide (D-GalN/LPS)-induced acute liver failure(ALF).Methods Firstly,C57BL/6 mice were randomly divided into control group(n =8),ALF 2h group(n =8),ALF 4h group (n =8),ALF 6h group (n =8).Secondly C57BL/6 mice were randomly divided into control group(n =8),ALF group(n =8),WY14643 group(n =8).To induce ALF,the mice were injected intraperitoneally with D-GalN (700 mg/kg) and LPS (10 μg/kg).WY14643 (6 mg/kg),the selective agonist of PPAR α,was administered via tail vein two hours prior to D-GalN/LPS exposure.Two,four,and six hours after D-GalN/LPS treatment in the first study,mice were anesthetized and blood was collected,6h after D-GalN/LPS treatment in the second study,blood was collected.The liver tissue was harvested for histology and mRNA extraction.Serum levels of ALT and AST were measured to evaluate the hepatic damage.Inflammatory cytokines (TNFα,IL-1β,IL-6) and chemokines (CXCL-1,CXCL-10) were detected by real-time quantitative PCR.Differential protein expression of p-NF-κBp65,p-JNK,p-ERK,p-p38 in inflammatory pathways was detected by Western blotting.Significance of inter-group differences was assessed by one-way ANOVA,and pairwise comparison was performed by the least significant difference test.Results The gene and protein expression of PPAR α were gradually reduced during the development of ALF.Compared with the model group,the liver architecture was better preserved almost with normal morphology in WY14643-treated mice.Serum ALT and AST levels in WY14643-treated group were significantly lower [ALT:(555 ±62)U/L vs (2 898 ±822) U/L,P <0.05; AST:(791 ±58) U/L vs (3 013 ±997)U/L,P < 0.05].The expression of proinflammatory cytokines and chemokines was significantly suppressed during the activation of PPAR α.In the second study,the levels of gene expression of proinflammatory cytokines and chemokines were detected in control group,ALF group and WY14643 group respectively as followings:TNFα (0.161 ± 0.085,7.996 ± 1.068,3.346 ± 0.94,P < 0.05),IL-1β(0.041 ±0.002,3.657 ±0.904,0.176±0.089,P<0.01),IL-6 (0.018 ±0.008,1.762 ±0.589,0.163±0.0487,P <0.05),CXCL-1 (0.063 ±0.008,7.881 ±0.966,2.737 ±0.864,P <0.01),CXCL-10 (0.054 ±0.005,5.671 ±0.948,2.578 ±0.804,P <0.05).Conclusion Our findings first demonstrate that PPARα protects liver from injury in an ALF mouse model by suppressing inflammatory response,indicating PPARα as a potential new therapeutic target for ALF.
8.Caspase-1 aggravates the D-galactosamine/lipopolysaccharide induced acute liver failure in mice through activating glycogen synthase kinase-3β
Rongrong YANG ; Feng REN ; Li ZHANG ; Xiangying ZHANG ; Hongbo SHI ; Dexi CHEN ; Zhongping DUAN ; Qi WANG
Chinese Journal of Microbiology and Immunology 2016;36(2):132-137
Objective To analyze the role of cysteinyl aspartate specific proteinase-1 (caspase-1) in a mouse model of D-galactosamine (D-GalN) and lipopolysaccharide (LPS) induced acute liver failure (ALF) and to study the possible mechanism. Methods C57BL/ 6 mice were randomly divided into four groups including control group, Z-WEHD-FMK (caspase-1 inhibitor) treatment group, ALF model group and Z-WEHD-FMK-treated ALF group. The mouse model of ALF was established by intraperitoneally injec-ting the mice with D-GalN (450 mg/ kg) and LPS (10 μg/ kg). The damages in liver tissues were evaluated based on the histopathological examination and the levels of alanine transaminase (ALT) and aspartate trans-aminase (AST) in serum samples. Western blot assay was performed to analyze the expression of caspase-1 and the phosphorylation of glycogen synthase kinase 3β (GSK-3β). The qRT-PCR was used to measure the expression of inflammatory cytokines at transcriptional level. Results The expression of caspase-1 at both mRNA and protein levels were gradually increased during the development of ALF. Compared with the mice with ALF, those in the Z-WEHD-FMK-treated ALF group showed less severe liver damages on histopatholog-ical examination and decreased levels of ALT and AST in serum samples [ALT: (479. 2±39. 5) U/ L vs (998. 5±60. 4 ) U/ L, P<0. 05; AST: ( 478. 5±28. 6) U/ L vs ( 1 180. 7±91. 4) U/ L, P<0. 05]. The expression of TNF-α, IL-1β, IL-18 and IL-33 at transcriptional level were significantly suppressed in mice with ALF upon the Z-WEHD-FMK intervention. Results of the Western blot assay indicated that Z-WEHD-FMK suppressed the activities of GSK-3β by enhancing its phosphorylation. Conclusion This study demon-strated that caspase-1 could promote the activation of GSK-3β resulting in the development of inflammation responses and liver damages during the development of ALF in mice.
9.Activated peroxisome proliferator-activated receptor αinhibiting the lipopolysaccharide-induced macrophage-mediated inflammatory responses by promoting the autophagy
Rongrong YANG ; Li ZHANG ; Xiangying ZHANG ; Hongbo SHI ; Dexi CHEN ; Zhongping DUAN ; Feng REN ; Qi WANG
Chinese Journal of Microbiology and Immunology 2015;(6):431-435
Objective To investigate the effects of peroxisome proliferator-activated receptor α( PPARα) on macrophage-mediated inflammatory responses with the interference of lipopolysaccharide and the possible mechanism.Methods The bone marrow stem cells were isolated from the femora of mice.The granulocyte-macrophage colony stimulating factor ( GM-CSF) was used to stimulate the in vitro differentiation from bone marrow stem cells into primary macrophages.An in vitro model with cultured cells expressing in-flammatory cytokines was established by treating the primary macrophages with lipopolysaccharide ( LPS) .A specific chemical agonist, Wy-14643, was used to activate PPARα. Autophagy inhibitors including 3-methyladenine (3-MA) and small interfering RNA against Atg7 ( Atg7 siRNA) were used to inhibit the autophagy.Western blot assay was performed to detect the expression of autophagy-related proteins ( Atg5, Atg7, Beclin-1 and LC3).The transcriptional levels of TNF-α, IL-1β, IL-6, Atg5, Atg7 and Beclin-1 were analyzed by qRT-PCR.Results Compared with the macrophages treated with LPS alone, those pretreated with various concentrations of Wy-14643 (10 μmol/L, 25 μmol/L and 50 μmol/L) showed inhibited ex-pression of proinflammatory cytokines ( TNF-α,IL-1βand IL-6) and enhanced expression of autophagy-relat-ed proteins (Atg5, Atg7 and Beclin-1) at mRNA level in a dose-dependent manner.The expression of auto-phagy-related proteins (Atg5, Atg7, Beclin-1 and LC3) by macrophages was promoted with the pretreatment of Wy-14643 as indicated by Western blot assay.The transcriptional levels of TNF-α, IL-1βand IL-6 were increased in Wy-14643 pretreated-macrophages after stimulation with 3-MA or Atg7 siRNA .Conclusion PPARαsuppressed the macrophage-mediated inflammatory responses by promoting autophagy, suggesting that the PPARα-autophagy pathway might be one of the signaling pathways regulating LPS induced-inflamma-tory responses.