ObjectiveTo investigate the effect of mitochondrial calcium uniporter （MCU） on the cytoskeleton of pancreatic ductal epithelial cells in a mouse model of acute pancreatitis （AP） induced by caerulein （CAE）， to analyze the role of MCU in the development of AP， and to provide a theoretical basis for clinical treatment. MethodsIn the in vivo experiment， wild-type male C57BL6/J mice， aged 4 weeks， were randomly divided into control group and AP group， with 6 mice in each group. The mice in the AP group were given intraperitoneal injection of CAE to establish a model of AP， and those in the control group were given intraperitoneal injection of an equal volume of normal saline. Serum and pancreatic tissue samples were collected after 24 hours of modeling. HE staining was used to observe pancreatic histopathological changes； Western Blot was used to measure the expression levels of MCU， glutathione peroxidase 4 （GPX4）， and acyl-CoA synthetase long chain family member 4 （ASCL4）； kits were used to measure the serum level of amylase. In the in vitro experiment， the human pancreatic ductal epithelial cell line HPDE6-C7 was co-cultured with CAE for 24 hours to establish an in vitro AP model， and the cells were divided into control group， CAE group， RR （an MCU activity inhibitor） group， CAE+RR group， Fer-1 （an ferroptosis inhibitor） group， CAE+Fer-1 group， Erastin （an ferroptosis inducer） group， and CAE+Erastin group. CCK-8 assay was used to observe the influence of different agents on cell viability； Western Blot was used to measure the expression levels of MCU， GPX4， and ASCL4； immunofluorescence assay was used to measure reactive oxygen species （ROS）， actin cytoskeleton， and monolayer permeability； kits were used to measure the concentrations of malondialdehyde （MDA）， glutathione （GSH）， Fe²⁺， and total iron. A one-way analysis of variance was used for comparison of continuous data between multiple groups， and the least significant difference t-test was used for comparison between two groups. ResultsIn the in vivo experiment， compared with the control group， the AP group had significant increases in pancreatic histopathological score， the serum level of amylase， and the expression levels of MCU and ASCL4， as well as a significant reduction in the expression of GPX4 （all P<0.05）. In the in vitro experiment， compared with the control group， the CAE group had significant increases in the expression levels of MCU and ASCL4， a significant reduction in the expression of GPX4， and significant increases in the concentrations of Fe²⁺， total iron， and MDA， the green fluorescence intensity of ROS， and monolayer permeability， as well as a significant reduction in the concentration of GSH （all P<0.05）， with the presence of actin cytoskeleton disruption. Compared with the CAE group， the CAE+RR group had a significant increase in the expression level of GPX4， a significant reduction in the expression level of ASCL4， and significant reductions in the concentrations of Fe²⁺， total iron， and MDA， the green fluorescence intensity of ROS， and monolayer permeability and a significant increase in the concentration of GSH （all P<0.05）， with alleviation of actin cytoskeleton disruption. Compared with the CAE group， the CAE+Fer-1 group had significant reductions in the concentrations of Fe²⁺， total iron， and MDA， the green fluorescence intensity of ROS， and monolayer permeability and a significant increase in the concentration of GSH （all P<0.05）， with alleviation of actin cytoskeleton disruption. Compared with the CAE group， the CAE+Erastin group had significant increases in the concentrations of Fe²⁺， total iron， and MDA， the green fluorescence intensity of ROS， and monolayer permeability and a significant reduction in the concentration of GSH （all P<0.05）， with aggravation of actin cytoskeleton disruption. ConclusionDuring the onset of AP， MCU mediates oxidative stress-induced ferroptosis and leads to the disruption of the pancreatic ductal epithelial barrier， which may be one of the possible pathogeneses of AP.

[ ABSTRACT] AIM:To investigate the effect of hydrogen sulfide ( H2 S) on airway inflammation induced by ozone (O3) exposure and its mechanisms.METHODS:C57BL/6 mice (n=32) were randomly divided into control group, O3 group, NaHS+O3 group and NaHS group.The mice in O3 group and O3 +NaHS group were exposed to 2.14 mg/m3 O3 for 3 h on days 1, 3 and 5, while the mice in control group and NaHS group were exposed to filtered air .NaHS (14μmol/kg) was administered intraperitoneally to the mice in NaHS group and O 3 +NaHS group 30 min before each exposure .After the last exposure for 24 h, the airway responsiveness was determined , and bronchoalveolar lavage fluid ( BALF) was collected for counting inflammatory cells and measuring total protein concentration .The lung tissues were collected for observing the morphological changes with HE staining .The levels of interleukin-6 ( IL-6 ) , interleukin-8 ( IL-8 ) , malondialdehyde ( MDA) and NF-κB p65 protein in the lungs were determined .RESULTS: Compared with control group , the airway re-sponsiveness, inflammatory cells, protein concentration, inflammation score, levels of IL-6, IL-8, MDA and NF-κB p65 in O3 group increased significantly , but these in NaHS+O3 group decreased compared with O 3 group.CONCLUSION: The present findings suggest that H 2 S attenuates O3 induced airway inflammation by inhibiting NF-κB expression and preventing lipid peroxidation .

OBJECTIVETo detect the expression of transient receptor potential canonical 1 (TRPC1) in a mouse model of ozone-induced lung inflammation and explore its role in lung inflammation.

METHODSIn a mouse model of lung inflammation established by ozone exposure, the expression of TRPC1 in the inflammatory lung tissues was detected by RT-PCR, Wstern blotting and immunohistochemistry.

RESULTSCompared to the control mice, the mice exposed to ozone showed significantly increased expression level of TRPC1 mRNA and protein in the inflammatory lung tissues (P<0.05). Immunohistochemistry showed increased TRPC1 protein expressions in the alveolar epithelial cells, bronchial epithelial cells, and inflammatory cells in the inflammatory lung tissues (P<0.05). The mRNA and protein expression levels of TRPC1 were positively correlated with the counts of white blood cells, macrophages, neutrophils and lymphocytes in the bronchoalveolar lavage fluid of the exposed mice (P<0.01).

CONCLUSIONTRPC1 may play a role in ozone-induced lung inflammation in mice.

Animals ; Bronchoalveolar Lavage Fluid ; Disease Models, Animal ; Gene Expression ; Inflammation ; pathology ; Lung ; metabolism ; pathology ; Mice ; Ozone ; adverse effects ; Pneumonia ; metabolism ; pathology ; RNA, Messenger ; TRPC Cation Channels ; metabolism

Objective To detect the expression of transient receptor potential canonical 1 (TRPC1) in a mouse model of ozone-induced lung inflammation and explore its role in lung inflammation. Methods In a mouse model of lung inflammation established by ozone exposure, the expression of TRPC1 in the inflammatory lung tissues was detected by RT-PCR, Wstern blotting and immunohistochemistry. Results Compared to the control mice, the mice exposed to ozone showed significantly increased expression level of TRPC1 mRNA and protein in the inflammatory lung tissues (P<0.05). Immunohistochemistry showed increased TRPC1 protein expressions in the alveolar epithelial cells, bronchial epithelial cells, and inflammatory cells in the inflammatory lung tissues (P<0.05). The mRNA and protein expression levels of TRPC1 were positively correlated with the counts of white blood cells, macrophages, neutrophils and lymphocytes in the bronchoalveolar lavage fluid of the exposed mice (P<0.01). Conclusion TRPC1 may play a role in ozone-induced lung inflammation in mice.

Objective To detect the expression of transient receptor potential canonical 1 (TRPC1) in a mouse model of ozone-induced lung inflammation and explore its role in lung inflammation. Methods In a mouse model of lung inflammation established by ozone exposure, the expression of TRPC1 in the inflammatory lung tissues was detected by RT-PCR, Wstern blotting and immunohistochemistry. Results Compared to the control mice, the mice exposed to ozone showed significantly increased expression level of TRPC1 mRNA and protein in the inflammatory lung tissues (P<0.05). Immunohistochemistry showed increased TRPC1 protein expressions in the alveolar epithelial cells, bronchial epithelial cells, and inflammatory cells in the inflammatory lung tissues (P<0.05). The mRNA and protein expression levels of TRPC1 were positively correlated with the counts of white blood cells, macrophages, neutrophils and lymphocytes in the bronchoalveolar lavage fluid of the exposed mice (P<0.01). Conclusion TRPC1 may play a role in ozone-induced lung inflammation in mice.