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Objective:To evaluate the role of cannabinoid receptor 2 (CB2R) in macrophage pyroptosis induced by lipopolysaccharide (LPS) in mice.Methods:Macrophage line RAW264.7 cells of mice were routinely cultured and divided into 3 groups ( n=18 each) using a random number table method: control group (group C), LPS group and LPS plus CB2R agonist HU308 group (group HU308). Group C received no mediation, LPS at the final concentration of 1 μg/ml was added in the other groups.After incubation for 15 min, HU308 with the final concentration of 10 μmol/L was added in group LPS+ HU308.All groups were then incubated for 6 h. The expression of nucleotide-binding oligomerization domain-like receptor containing pyrin domain 3 (NLRP3), caspase-1, caspase-11 and gasdermin D (GSDMD) mRNA was measured by real-time polymerase chain reaction, the expression of NLRP3, caspase-1, caspase-11, GSDMD and C-terminal domain of human GSDMD (GSDMD-C) was detected by Western blot, and the concentrations of interleukin-18 (IL-18) and IL-1β in the supernatant were determined by enzyme-linked immunosorbent assay.GSDMD-C/GSDMD ratio was calculated. Results:Compared with group C, the expression of NLRP3, caspase-1, caspase-11, GSDMD and GSDMD-C was significantly up-regulated, GSDMD-C/GSDMD ratio was increased, and the concentrations of IL-18 and IL-1β in the supernatant were increased in group LPS ( P<0.05). Compared with group LPS, the expression of NLRP3, caspase-1, caspase-11, GSDMD and GSDMD-C was significantly down-regulated, GSDMD-C/GSDMD ratio was decreased, and the concentrations of IL-18 and IL-1β were decreased in group HU308 ( P<0.05). Conclusion:CB2R is involved in macrophage pyroptosis induced by LPS in mice.
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Objective To investigate the role of activated cannabinoid receptor 2 (CB2R) in lipopolysaccharide (LPS)-induced secretion of RAW264.7 macrophage inflammatory cytokines and its possible mechanism. Methods Macrophages were seeded in 6-well plates (2 mL/well) at the density of 1×105 cells/mL and randomly divided into four groups (n=6 each group): control group (group C), LPS group (group LPS), LPS plus CB2R agonist HU308 group (group LPS+HU308), and LPS plus HU308 plus 3-Methyladenine group (group LPS+HU308+3-MA). LPS with the final concentration of 1 μg/mL were added in group LPS, group LPS+HU308 and group LPS+HU308+3-MA. After incubation for 15 min, 3-MA with a final concentration of 10 mmol/L was added into group LPS+HU308+3-MA . HU308 with the final concentration of 10 μmol/L was added in group LPS+HU308 and group LPS+HU308+3-MA at 15 min after 3-MA intervention, and the cells were then incubated for 24 h. The concentrations of TNF-α, IL-18 and IL-1β in supernatant serum of each group were determined by ELISA. The expressions of ICAM-1 and NLRP3 mRNA were detected by RT-PCR. The expressions of LC3 and Beclin1 were detected by Western blot, and the ratio of LC3-Ⅱ/LC3-Ⅰ was calculated. LSD-t test was used for sample pairwise comparison, and one way ANOVA for inter-group comparison. A P<0.05 was considered statistically significant. Results Compared with group C, the concentrations of TNF-α [(228.86±10.20) pg/mL vs (140.05±5.54) pg/mL], IL-1β [(363.62±8.14) pg/mL vs (244.82±9.11) pg/mL], and IL-18 [(293.28±13.57) pg/mL vs (202.84±9.54) pg/mL] in supernatant serum were increased (all P<0.05), the expressions of ICAM-1 [(5.88±0.32) vs (1.00±0.03)] and NLRP3 [(8.07±0.93) vs (1.01±0.05)] mRNA were increased (all P<0.05), the expressions of LC3-Ⅱ/LC3-Ⅰ ratio [(0.50±0.03) vs (0.40±0.06)] and Beclin1 [(0.51±0.04) vs (0.16±0.03)] were up-regulated in group LPS (all P<0.05). Compared with group LPS, the concentrations of TNF-α [(165.44±7.07) pg/mL], IL-1β [(272.09±3.35) pg/mL] and IL-18 [(220.41±6.01) pg/mL] in supernatant serum were significantly decreased (all P<0.05), the expressions of ICAM-1 [(3.21±0.35)] and NLRP3 [(1.54±0.30)] mRNA were decreased (all P<0.05), the expressions of LC3-Ⅱ/LC3-Ⅰ ratio [(0.71±0.03)] and Beclin1 [(0.71±0.02)] were up-regulated in group LPS+HU308 (all P<0.05). Compared with group LPS+HU308, the concentrations of TNF-α [(197.06±5.59) pg/mL], IL-1β [(318.98±11.54) pg/mL] and IL-18 [(243.33±8.71) pg/mL] in supernatant serum were significantly increased (all P<0.05), the expressions of ICAM-1 [(4.04±0.21)] and NLRP3 [(5.87±0.77)] mRNA were increased (all P<0.05), the expressions of LC3-Ⅱ/LC3-Ⅰ ratio [(0.44±0.08)] and Beclin1 [(0.32±0.03)] were down-regulated in group LPS+HU308+3-MA (all P<0.05). Conclusions Activation of cannabinoid receptor 2 can alleviate LPS-induced the secretion of RAW264.7 macrophage inflammatory cytokines, and its mechanism may be related to enhanced autophagy.
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Objective To evaluate the effect of activating cannabinoid receptor 2 (CB2R) on sepsis-induced acute lung injury and the role of autophagy in mice.Methods Twenty-four SPF male C57BL/6 mice,aged 8-10 weeks,weighing 20-25 g,were divided into 4 groups (n=6 each) using a random number table method:sham operation group (group Sham),sepsis group (group Sep),sepsis plus CB2R agonist HU308 group (group Sep+HU308) and sepsis plus HU308 plus autophagy inhibitor 3-methyladenine group (group Sep+HU308+3-MA).Sepsis was induced by cecal ligation and puncture in anesthetized mice.HU308 2.5 mg/kg was intraperitoneally injected at 15 min after surgery in Sep+HU308 and Sep+ HU308+3-MA groups,and 15 min later 3-MA 10 mg/kg was intraperitoneally injected in group Sep+ HU308+3-MA.Lung tissues were obtained at 12 h after surgery and stained with haematoxylin and eosin for examination of the pathological changes which were scored and for determination of the expression of tumornecrosis factor-alpha (TNF-α),interleukin-18 (IL-18) and IL-1β mRNA (by real-time polymerase chain reaction),expression of autophagy-related protein 5 (Atg5) (by immuno-histochemistry),and expression of microtubule-associated protein 1 light chain 3 (LC3),Beclin-1 and p62 (by Western blot).The ratio of LC3Ⅱ to LC3Ⅰ (LC3Ⅱ/LC3Ⅰ ratio) was calculated.Results Compared with group Sham,the expression of TNF-α,IL-18 and IL-1β mRNA was significantly up-regulated,and LC3 Ⅱ/LC3 Ⅰ ratio and lung injury score were increased in the other three groups,the expression of Beclin-1 was up-regulated,and the expression of p62 was down-regulated in group Sep and group Sep+HU308,and the expression of p62 was significantly up-regulated in group Sep+HU308+3-MA (P＜0.05).Compared with group Sep,the expression of TNF-α,IL-18 and IL-1β mRNA was significantly down-regulated,the expression of Atg5 was up-regulated,and lung injury score was decreased in group Sep+ HU308 and group Sep+ HU308 + 3-MA,LC3Ⅱ/LC3Ⅰ ratio was increased,the expression of Beclin-1 was up-regulated,and the expression of p62 was down-regulated in group Sep+HU308,and the expression of Beclin-1 was down-regulated,and the expression of p62 was up-regulated in group Sep + HU308 + 3-MA (P ＜ 0.05).Compared with group Sep+ HU308,the expression of TNF-α,IL-18 and IL-1β mRNA was significantly up-regulated,the expression of Atg5 and Beclin-1 was down-regulated,LC3Ⅱ/LC3Ⅰ ratio was decreased,the expression of p62 was up-regulated,and lung injury scores were increased in group Sep+HU308+3-MA (P＜0.05).Conclusion Activating CB2R can alleviate acute lung injury in septic mice,and the mechanism may be partially related to enhancing autophagy and reducing inflammatory responses.
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Objective To evaluate the role of M3 receptors in penehyclidine hydrochloride ( PHC)-induced reduction of lipopolysaccharide ( LPS)-induced injury to human pulmonary microvascular endotheli-al cells ( PMVECs) . Methods Human PMVECs transfected with M3 shRNA were seeded in 6-well plates (2 ml∕hole) or in culture flasks (4 ml∕flask) at the density of 1×105 cells∕ml and divided into 5 groups ( n=5 each) using a random number table method: control group ( group C) , LPS group, PHC plus LPS group ( group P+LPS) , LPS plus M3 shRNA transfection group ( group LPS+shRNA) , and PHC plus LPS plus M3 shRNA transfection group ( group P+LPS+shRNA) . Group C received no mediation, and LPS was added at the final concentration of 0. 1 μg∕ml in the other groups. PHC 2 μg∕ml was added at 1 h before adding LPS in P+LPS and P+LPS+shRNA groups. The cells were transfected with plasmid containing 2. 5 nmol∕L M3 receptor shRNA in LPS+shRNA group and P+LPS+shRNA group. Contents of filamentous actin ( F-actin) in endothelial cells were measured by flow cytometry at 1 h after adding LPS. The expression of myosin light chain kinase ( MLCK) and VE-cadherin protein was examined by immunofluorescence. The ex-pression of nuclear factor kappa B ( NF-κB) p65 and IκB was detected by Western blot. Contents of tumor necrosis factor-alpha ( TNF-α) and interleukin-6 ( IL-6) were determined by enzyme-linked immunosorbent assay. The M3 receptor mRNA transcription was detected by real-time polymerase chain reaction at 10, 30 and 60 min after adding LPS. Results Compared with group C, F-actin content was significantly de-creased, the expression of VE-cadherin and IκB was down-regulated, the contents of TNF-αand IL-6 were increased, and the expression of MLCK and NF-κB p65 was up-regulated in LPS and P+LPS groups ( P<0. 05) . Compared with group C, the expression of M3 receptor mRNA was significantly up-regulated in group LPS ( P<0. 05) , and no significant change was found in group P+LPS ( P>0. 05) . Compared with group LPS, F-actin content was significantly increased, the expression of VE-cadherin and IκB was up-reg-ulated, the contents of TNF-αand IL-6 were decreased, and the expression of MLCK, NF-κB p65 and M3 receptor mRNA was down-regulated in group P+LPS and group LPS+shRNA ( P<0. 05) . Compared with group P+LPS, F-actin content was significantly increased, the expression of VE-cadherin and IκB protein was up-regulated, TNF-α and IL-6 contents were decreased, and the expression of MLCK, NF-κB p65 and M3 receptor mRNA was down-regulated in group P+LPS+shRNA ( P<0. 05) . Conclusion PHC re-duces LPS-induced injury to human PMVECs through interfering with M3 receptors and inhibiting NF-κB-mediated inflammatory responses.
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Objective@#To understand the molecular evolution characteristics of the nucleoprotein (N) genes and epidemiological feature of 118 rabies virus (RABV) strains isolated in Yunnan province, China from 2006 to 2015.@*Methods@#The brain tissue samples from mad dogs, suspicious sick dogs, sick cow, and human brain tissue, saliva and CSF samples from rabies patients were collected in Yunnan province to detect the viral antigen by direct immunofluorescence assay (DFA). The viral RNA from positive samples was extracted. Coding region of N gene was amplified by RT-PCR and sequenced. The phylogenetic tree was constructed by Neighbor-Joining method of MEGA5.0 software.@*Results@#The sequences of N genes of 91 RABV strains in Yunnan from 2012 to 2015 were obtained. With the sequences of N genes of 27 RABV strains in Yunnan from 2006 to 2011 and 29 RABV strains from Southeast Asian Countries, the phylogenetic analysis was performed. RABV strains in Yunnan were divided into clades YN-A (105 strains), YN-B (6 strains), YN-C (7 strains), which belonged to clades China-I, China-VI, China-II respectively. Clade YN-A was epidemic every year from 2006 to 2015, of them, 14 strains from 2006 to 2011 and 91 strains from 2012 to 2015 were distributed in 13 prefectures (cities) of Yunnan. Clades YN-B and YN-C were epidemic only from 2006 to 2010 and from 2008 to 2011 respectively. The regional distribution of clades YN-B and YN-C was limited. The strains of YN-A and YN-C were closely related to the strains of clades China-I and China-II from neighboring Sichuan, Guizhou, Guangxi and Hunan provinces. The strains of YN-B were closely related to the strains from Myanmar, Laos, Vietnam and Cambodia.@*Conclusions@#Three RABV clades with multiple transmission sources were identified in Yunnan. Clade YN-A was widely distributed in rabies endemic area in Yunnan from 2006 to 2015, and it has strong ability to spread as principal clade in Yunnan. Since 2012, clades YN-B and YN-C were not found again in Yunnan.
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Objective To evaluate the role of β-arrestin-1 in penehyclidine hydrochloride (PHC)-induced inhibition of lipopolysaccharide (LPS)-caused increase in pulmonary microvascular permeability in human pulmonary microvascular endothelial cells (PMVECs).Methods Human PMVECs were seeded in 6-well plates (2 ml/well) or in culture flasks (4 ml/flask) at the density of 1 × 105 cells/ml and divided into 5 groups (n=15 each) using a random number table:empty plasmid transfection group (group C),LPS plus empty plasmid transfection group (LPS group),PHC plus LPS plus empty plasmid transfection group (P+LPS group),LPS plus β-arrestin-1 short hairpin RNA (shRNA) transfection group (LPS+shRNA group) and PHC plus LPS plus β-arrestin-1 shRNA transfection group (P+LPS+shRNA group).In LPS and LPS+shRNA groups,the cells were transfected with empty plasmid 1.5 μg or with plasmid containing 15 nmol/L β-arrestin-1 shRNA,LPS with the final concentration of 0.1 μg/ml was added at 24 h of incubation,and the cells were then incubated for 1 h.In P+LPS and P+LPS+shRNA groups,the cells were transfected with empty plasmid 1.5 μg or with plasmid containing 15 nmol/L β-arrestin-1 shRNA,PHC with the final concentration of 2 μg/ml was added at 24 h of incubation,LPS with the final concentration of 0.1 μg/ml was added at 1 h of incubation,and the cells were then incubated for 1 h.The cell permeability was measured using Transwell chambers.The expression of heat shock protein (HSP27) was detected by immunofluorescence.The expression of β-arrestin-1,p38 mitogen-activated protein kinase (p38MAPK) and phosphorylated p38MAPK (p-p38MAPK) was detected by Western blot.The ratio of pp38MAPK/p38MAPK was calculated.Results Compared with group C,the cell permeability was significantly increased,the expression of HSP27 was up-regulated,p-p38MAPK/p38MAPK ratio was increased,and the expression of β-arrestin-1 was down-regulated in LPS,LPS + shRNA and P + LPS + shRNA groups (P＜0.05),and no significant change was found in the parameters mentioned above in group P+LPS (P＞ 0.05).Compared with group LPS,the cell permeability was significantly decreased,the expression of HSP27 was down-regulated,p-p38MAPK/p38MAPK ratio was decreased,and the expression of β-arrestin1 was up-regulated in group P +LPS,and p-p38MAPK/p38MAPK ratio was significantly increased (P＜0.05),and no significant change was found in the other parameters in group P+LPS+shRNA (P＞0.05).Compared with group P+LPS,the cell permeability was significantly increased,the expression of HSP27 was up-regulated,p-p38MAPK/p38MAPK ratio was increased,and the expression of β-arrestin-1 was down-regulated in group P+LPS+shRNA (P＜0.05).Conclusion The mechanism by which PHC inhibits LPS-induced increase in pulmonary microvascular permeability is totally related to β-arrestin-1 in human PMVECs.
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Objective To evaluate the role of M3 receptor in penehyclidine hydrochloride(PHC)-induced reduction of increased permeability of human pulmonary microvascular endothelial cells (PMVECs) caused by endotoxin and the relationship with mitogen-activated protein kinase (MAPK) signaling pathway.Methods Human PMVECs were seeded in 6-well plates (2 ml/hole) or in culture flasks (4 ml/flask) at the density of 1 × 105 cells/ml and randomly divided into 6 groups (n=5 each):control group (group C),M3 receptor shRNA transfection group (group shRNA),lipopolysaccharide (LPS) group,penehyclidine plus LPS group (group P+LPS),LPS plus M3 receptor shRNA transfection group (group LPS+shRNA) and PHC plus LPS plus M3 shRNA transfection group (group P+LPS+shRNA).The cells were transfected with shRNA plasmid containing 2.5 nmol/L M3 receptors in shRNA,LPS+shRNA and P+LPS+shRNA groups.LPS at the final concentration of 0.1 μg/ml was added at 24 h of incubation and then cells were incubated for 1 h in LPS and LPS+shRNA groups.PHC at the final concentration of 2 μg/ml was added at 24 h of incubation,cells were incubated for 1 h,then LPS at the final concentration of 0.1 μg/ml was added,and cells were incubated for another l h in P+LPS and P+LPS+shRNA groups.The permeability of PMVECs was measured using Transwell assay.The expression of phosphorylated p38 MAPK (p-p38 MAPK)and phosphorylated extracellular signal-regulated protein kinase 1/2 (p-ERK1/2) was detected by Western blot,the expression of heat shock protein 27 (HSP27) using immunofluorescent staining,and the expression of M3receptor mRNA by real-time polymerase chain reaction.Results Compared with group C,M3 receptor mRNA expression was significantly down-regulated in group shRNA,and the permeability of cells was significantly increased,and the expression of p-p38 MAPK,p-ERK1/2,HSP27 and M3 receptor mRNA was up-regulated in group LPS (P＜0.05).The permeability of cells was significantly decreased,and the expression of p-p38 MAPK,p-ERK1/2,HSP27 and M3 receptor mRNA was down-regulated in P+ LPS,LPS+shRNA and P+LPS+shRNA groups as compared with group LPS,and in group P+LPS+shRNA as compared with group LPS+shRNA (P＜0.05).Conclusion The mechanism by which PHC reduces endotoxin-caused increased permeability of human PMVECs is related to inhibiting activation of MAPK signaling pathway after down-regulating M3 receptor.