Objective To investigate the therapeutic potential of human umbilical cord-derived mesenchymal stem cells(hUCMSCs)in modulating the cGAS-STING-NF-κB signaling pathway in chronic intermittent hypoxia(CIH)mice.Methods Twenty-four C57BL/6 mice were divided into the control group,the model group,the hUCMSCs group and the hUCMSCs+STING agonist(DMXAA)group,with 6 mice in each group.Except for the control group,the other groups were exposed to hypoxic conditions for 8 hours daily for a total of 8 weeks to establish the CIH mouse model.After 8 weeks,mice were anesthetized for cardiac blood collection followed by euthanasia and lung tissue collection.Serum levels of IL-6,TNF-α,IL-1β and IL-17A were measured by ELISA.Pulmonary inflammatory infiltration and collagen deposition were assessed by HE and Masson staining.E-Cadherin and α-SMA expression levels were evaluated by immunohistochemistry.Expression levels of cGAS,STING and NF-κB mRNA were detected by RT-qPCR,while protein expression levels of E-Cadherin,N-Cadherin,α-SMA,Vimentin,cGAS,STING and NF-κB were analyzed by Western blot assay.Results Compared with the control group,levels of IL-6,IL-1β,TNF-α and IL-17A increased in the model group,inflammation and fibrosis scores increased,mRNA expression levels of cGAS,STING and NF-κB increased,and protein expression levels of N-Cadherin,α-SMA,Vimentin,cGAS,STING and NF-κB increased.In contrast,E-Cadherin protein expression was significantly decreased(P＜0.05).Compared with the model group,IL-6,IL-1β,TNF-α and IL-17A decreased in the hUCMSCs group,mRNA expression levels of cGAS,STING and NF-κB were decreased,protein expression levels of N-Cadherin,α-SMA,Vimentin,cGAS,STING and NF-κB were also decreased.Meanwhile,E-Cadherin protein expression was significantly increased(P＜0.05).STING activator DMXAA reversed the protective effects of hUCMSCs in CIH mice(P＜0.05).Conclusion Intravenous administration of hUCMSCs alleviates pulmonary inflammatory infiltration and epithelial-mesenchymal transition in mouse model of intermittent hypoxia,which may be related to the down-regulation of the cGAS-STING-NF-κBsignaling pathway.

Objective To investigate the therapeutic potential of human umbilical cord-derived mesenchymal stem cells(hUCMSCs)in modulating the cGAS-STING-NF-κB signaling pathway in chronic intermittent hypoxia(CIH)mice.Methods Twenty-four C57BL/6 mice were divided into the control group,the model group,the hUCMSCs group and the hUCMSCs+STING agonist(DMXAA)group,with 6 mice in each group.Except for the control group,the other groups were exposed to hypoxic conditions for 8 hours daily for a total of 8 weeks to establish the CIH mouse model.After 8 weeks,mice were anesthetized for cardiac blood collection followed by euthanasia and lung tissue collection.Serum levels of IL-6,TNF-α,IL-1β and IL-17A were measured by ELISA.Pulmonary inflammatory infiltration and collagen deposition were assessed by HE and Masson staining.E-Cadherin and α-SMA expression levels were evaluated by immunohistochemistry.Expression levels of cGAS,STING and NF-κB mRNA were detected by RT-qPCR,while protein expression levels of E-Cadherin,N-Cadherin,α-SMA,Vimentin,cGAS,STING and NF-κB were analyzed by Western blot assay.Results Compared with the control group,levels of IL-6,IL-1β,TNF-α and IL-17A increased in the model group,inflammation and fibrosis scores increased,mRNA expression levels of cGAS,STING and NF-κB increased,and protein expression levels of N-Cadherin,α-SMA,Vimentin,cGAS,STING and NF-κB increased.In contrast,E-Cadherin protein expression was significantly decreased(P＜0.05).Compared with the model group,IL-6,IL-1β,TNF-α and IL-17A decreased in the hUCMSCs group,mRNA expression levels of cGAS,STING and NF-κB were decreased,protein expression levels of N-Cadherin,α-SMA,Vimentin,cGAS,STING and NF-κB were also decreased.Meanwhile,E-Cadherin protein expression was significantly increased(P＜0.05).STING activator DMXAA reversed the protective effects of hUCMSCs in CIH mice(P＜0.05).Conclusion Intravenous administration of hUCMSCs alleviates pulmonary inflammatory infiltration and epithelial-mesenchymal transition in mouse model of intermittent hypoxia,which may be related to the down-regulation of the cGAS-STING-NF-κBsignaling pathway.