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1.
J Immunol ; 207(8): 2118-2128, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34507947

RESUMO

Sepsis is a life-threatening organ dysfunction caused by a dysfunctional host response to infection. Neutrophils play a protective role by releasing antibacterial proteins or by phagocytizing bacteria. However, excess neutrophils can induce tissue damage. Recently, a novel intercellular communication pathway involving extracellular vesicles (EVs) has garnered considerable attention. However, whether EVs secreted by macrophages mediate neutrophil recruitment to infected sites has yet to be studied. In this study, we assessed the chemotactic effect of EVs isolated from mouse Raw264.7 macrophages on mouse neutrophils and found that CXCL2 was highly expressed in these EVs. By regulating CXCL2 in Raw264.7 macrophages, we found that CXCL2 on macrophage EVs recruited neutrophils in vitro and in vivo. The CXCL2 EVs activated the CXCR2/PKC/NOX4 pathway and induced tissue damage. This study provides information regarding the mechanisms underlying neutrophil recruitment to tissues and proposes innovative strategies and targets for the treatment of sepsis.

2.
Clin Psychol Psychother ; 28(5): 1146-1159, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33592682

RESUMO

The aim of current study was to investigate risk perception of COVID-19 pandemic, sleep quality and time change of leisure activity and their correlations with posttraumatic stress disorder (PTSD) in healthcare workers (HCWs) from four designated hospitals in China. Medical staffs (n = 317) from three designated hospitals in Guangdong Province and one designated hospital in Guangxi Province were surveyed on their demographic information, sleep quality and time change of leisure activity, risk perception of pandemic and PTSD symptoms (by using PTSD checklist for DSM-5 (PCL-5)). Hierarchical regression and structural equation model (SEM) were used to examine the correlated factors of PTSD. The prevalence of high level of PTSD symptoms (PCL-5 > =33, a probable diagnosis of PTSD) was 10.7%. Regression analysis found that risk perception (dread: ß = 0.142, p < 0.01; familiarity: ß = 0.203, p < 0.01), sleep quality (ß = 0.250, p < 0.001), time change of leisure activity (ß = -0.179, p < 0.01), were independently correlated with PTSD severity, which was further confirmed by SEM. Locations of COVID-19-related hazards were significant different in cognitive map of risk perception between groups with high and low levels of PTSD symptoms. Risk perception of COVID-19 pandemic influenced PTSD symptoms in HCWs. Adequate time for leisure activity and good sleep quality protected some HCWs against PTSD symptoms under the influence of pandemic. More researches were warranted to understand the path from pre-factors of risk perception to its psychological consequences among HCWs.

3.
Clin Sci (Lond) ; 134(7): 853-869, 2020 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-32227122

RESUMO

Angiotensin II (Ang II) has been reported to aggravate hepatic fibrosis by inducing NADPH oxidase (NOX)-dependent oxidative stress. Alamandine (ALA) protects against fibrosis by counteracting Ang II via the MAS-related G-protein coupled (MrgD) receptor, though the effects of alamandine on hepatic fibrosis remain unknown. Autophagy activated by reactive oxygen species (ROS) is a novel mechanism of hepatic fibrosis. However, whether autophagy is involved in the regulation of Ang II-induced hepatic fibrosis still requires investigation. We explored the effect of alamandine on hepatic fibrosis via regulation of autophagy by redox balance modulation. In vivo, alamandine reduced CCl4-induced hepatic fibrosis, hydrogen peroxide (H2O2) content, protein levels of NOX4 and autophagy impairment. In vitro, Ang II treatment elevated NOX4 protein expression and ROS production along with up-regulation of the angiotensin converting enzyme (ACE)/Ang II/Ang II type 1 receptor (AT1R) axis. These changes resulted in the accumulation of impaired autophagosomes in hepatic stellate cells (HSCs). Treatment with NOX4 inhibitor VAS2870, ROS scavenger N-acetylcysteine (NAC), and NOX4 small interfering RNA (siRNA) inhibited Ang II-induced autophagy and collagen synthesis. Alamandine shifted the balance of renin-angiotensin system (RAS) toward the angiotensin converting enzyme 2 (ACE2)/alamandine/MrgD axis, and inhibited both Ang II-induced ROS and autophagy activation, leading to attenuation of HSCs migration or collagen synthesis. In summary, alamandine attenuated liver fibrosis by regulating autophagy induced by NOX4-dependent ROS.


Assuntos
Antioxidantes/farmacologia , Autofagia/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Células Estreladas do Fígado/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Cirrose Hepática Experimental/prevenção & controle , Fígado/efeitos dos fármacos , NADPH Oxidase 4/metabolismo , Oligopeptídeos/farmacologia , Enzima de Conversão de Angiotensina 2 , Animais , Tetracloreto de Carbono , Células Cultivadas , Doença Hepática Induzida por Substâncias e Drogas/enzimologia , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/patologia , Colágeno/metabolismo , Células Estreladas do Fígado/enzimologia , Células Estreladas do Fígado/ultraestrutura , Fígado/enzimologia , Fígado/ultraestrutura , Cirrose Hepática Experimental/induzido quimicamente , Cirrose Hepática Experimental/enzimologia , Cirrose Hepática Experimental/patologia , Masculino , Proteínas do Tecido Nervoso/efeitos dos fármacos , Proteínas do Tecido Nervoso/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Peptidil Dipeptidase A/metabolismo , Ratos Sprague-Dawley , Receptores Acoplados a Proteínas G/efeitos dos fármacos , Receptores Acoplados a Proteínas G/metabolismo , Sistema Renina-Angiotensina/efeitos dos fármacos , Transdução de Sinais
4.
Biomed Res Int ; 2019: 1806234, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31531346

RESUMO

We previously demonstrated that angiotensin-(1-7) (Ang-(1-7)), an essential endocrine factor, inhibits the NLRP3 inflammasome by regulating reactive oxygen species (ROS) in fibrotic livers. We also demonstrated that the NLRP3 inflammasome contributes to the liver damage induced by pyroptosis after heatstroke. However, the role of Ang-(1-7) in the hepatocytes under heat stress remains uncertain. We aimed to examine the change in angiotensin peptides in the livers affected by heatstroke and the effect on the ROS-NLRP3 inflammatory signalling pathway. In vivo, increased angiotensin II (Ang II) and decreased Ang-(1-7) in the serum of heatstroke patients suffering from hepatic dysfunction were observed. The change in angiotensin peptides was considered a potential biomarker that could be used to predict hepatic dysfunction. Enhanced Ang II and attenuated Ang-(1-7) levels were also observed in the liver tissue of heatstroke rats, which were consistent with their receptors and converting enzymes. Hepatic damage associated with increased ROS and protein expression levels of NOX4, NLRP3, caspase-1, and IL-1ß was attenuated by AVE 0991, an analogue of Ang-(1-7). In vitro, pyroptosis, characterized by activated caspase-1 and IL-1ß, was observed in hepatocytes under heat stress, which was enhanced by Ang II and attenuated by antioxidants, NOX4 siRNA, and AVE 0991. In summary, AVE 0991 attenuates pyroptosis and liver damage induced by heat stress by inhibiting the ROS-NLRP3 inflammatory signalling pathway.


Assuntos
Golpe de Calor/tratamento farmacológico , Imidazóis/farmacologia , Inflamação/tratamento farmacológico , Cirrose Hepática/tratamento farmacológico , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Piroptose/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Angiotensina I/metabolismo , Angiotensina II/metabolismo , Animais , Biomarcadores/metabolismo , Golpe de Calor/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Inflamassomos/metabolismo , Inflamação/metabolismo , Interleucina-1beta/metabolismo , Fígado , Cirrose Hepática/metabolismo , Masculino , Fragmentos de Peptídeos/metabolismo , Estudos Prospectivos , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
5.
Nan Fang Yi Ke Da Xue Xue Bao ; 35(12): 1739-44, 2015 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-26714908

RESUMO

OBJECTIVE: To investigate the effect of losartan in regulating oxidative stress and the underlying mechanism in mice with ventilator-induced lung injury. METHODS: Thirty-six male C57 mice were randomly divided into control group, losartan treatment group, mechanical ventilation model group, and ventilation plus losartan treatment group. After the corresponding treatments, the lung injuries in each group were examined and the expressions of caveolin-1 and NOX4 in the lung tissues were detected. RESULTS: The mean Smith score of lung injury was significantly higher in mechanical ventilation model group (3.3) than in the control group (0.4), and losartan treatment group (0.3); the mean score was significantly lowered in ventilation plus losartan treatment group (2.3) compared with that in the model group (P<0.05). The expressions of caveolin-1 and NOX4 were significantly higher in the model group than in the control and losartan treatment groups (P<0.05) but was obviously lowered after losartan treatment (P<0.05). Co-expression of caveolin-1 and NOX4 in the lungs was observed in the model group, and was significantly decreased after losartan treatment. CONCLUSION: Losartan can alleviate ventilator-induced lung injury in mice and inhibit the expression of caveolin-1 and NOX4 and their interaction in the lungs.


Assuntos
Caveolina 1/metabolismo , Losartan/farmacologia , NADPH Oxidases/metabolismo , Estresse Oxidativo , Lesão Pulmonar Induzida por Ventilação Mecânica/tratamento farmacológico , Animais , Pulmão/metabolismo , Pulmão/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , NADPH Oxidase 4 , Respiração Artificial , Lesão Pulmonar Induzida por Ventilação Mecânica/metabolismo
6.
Nan Fang Yi Ke Da Xue Xue Bao ; 35(10): 1457-62, 2015 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-26547341

RESUMO

OBJECTIVE: To observe epithelial-mesenchymal phenotypes and oxidative stress related protein expressions of the liver cells in a rat model of liver fibrosis induced by bile duct ligation and recanalization. METHODS: Twenty-four male Wistar rats were randomized into 4 groups, including a sham-operated group, two bile duct ligation groups with ligation for 2 and 4 weeks, and a bile duct ligation group with a 2-week ligation followed by a 2-week recanalization. HE staining and Masson staining were used to assess liver fibrosis in the rats, and immunohistochemistry and Western blotting were employed to detect expressions of the epithelial and mesenchymal marker proteins and oxidative stress-related proteins. RESULTS: Compared with the sham-operated group, the rats with bile duct ligation showed obvious liver fibrosis, which worsened as the ligation time extended, accompanied by significantly increased expression of α-SMA, collagen I, NOX(4) and vimetin and reduced E-cadherin expression. Compared with the rats with bile duct ligation for 4 weeks, the rats in bile duct ligation-recanalization group showed obviously lessened liver fibrosis, significantly lowered expressions of NOX(4) and mesenchymal cell maker proteins, and enhanced expressions of epithelial cell marker proteins. CONCLUSION: Bile duct ligation up-regulates mesenchymal phenotype-related proteins and NOX(4) protein expression and down-regulates the expression of epithelial phenotype-related proteins, and these changes can be reversed by subsequent bile duct recanalization.


Assuntos
Células Epiteliais/citologia , Hepatócitos/citologia , Cirrose Hepática/metabolismo , NADPH Oxidases/metabolismo , Actinas/metabolismo , Animais , Ductos Biliares/cirurgia , Caderinas/metabolismo , Colágeno Tipo I/metabolismo , Modelos Animais de Doenças , Células Epiteliais/metabolismo , Hepatócitos/metabolismo , Ligadura , Masculino , NADPH Oxidase 4 , Estresse Oxidativo , Fenótipo , Ratos , Ratos Wistar , Vimentina/metabolismo
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