Effects And Mechanism Of TRIM21 In Inflammatory Response And Vascular Remodeling After Arterial Injury

BackgroundVascular smooth muscle cells(VSMCs)located in the vascular wall media begin to proliferate when arterial vascular injury occurs,undergo phenotypic transformation and migrate to the vascular intima,causing extracellular matrix deposition and local inflammatory responses,which in turn lead to intravascular Membrane hyperplasia induces vascular remodeling.Tripartite motif-containing protein 21(TRIM21)is a member of the TRIM protein family,which can affect cell proliferation,invasion,migration and differentiation.The current research on TRIM21 mainly focuses on the aspects of immunity,and tumorigenesis.The role and mechanism of TRIM21 in inflammatory response and vascular remodeling after arterial injury still needs further research.ObjectiveTo explore the effect and mechanism of TRIM21 on inflammation and vascular remodeling after arterial injury.Research methods1.A mouse carotid artery injury model was constructed,and the changes of blood vessel morphology following carotid artery injury in each group were examined by HE staining.The expression of TRIM21 in blood vessels was detected by RT-PCR,western blot and immunohistochemical staining.2.TRIM21 knockout mice was constructed to interfere with the expression of TRIM21.The construction of knockout mice was identified by RT-PCR,western blot and immunofluorescence methods,and the effects of TRIM21 knockout mice on vascular proliferation,apoptosis,oxidative stress and inflammatory response following arterial vascular injury were explored.3.The primary mouse VSMCs cells were extracted from both TRIM21 knockout and wild-type mice,and the VSMCs were stimulated by LPS to simulate the process of smooth muscle cell proliferation.The effects of TRIM21 knockout on smooth muscle cell proliferation,migration,oxidative stress and inflammatory response in vitro were detected by RT-PCR,western blot and immunofluorescence.4.RT-PCR,western blot and immunofluorescence were used to detect the protein expression of NF-κB pathway after LPS induction by knocking out TRIM21.Following the inhibition of NF-κB expression,rescue experiments were used to explore the effect of overexpression of TRIM21 on smooth muscle,and evaluate whether the effects of oxidative stress,inflammatory factor release,proliferation and migration of cells still exist.Results1.After vascular injury,the m RNA and protein expressions of TRIM21 in blood vessels were gradually increased,which reached the peak on the 7th day after injury,and the elevated expression of TRIM21 was correlated with PCNA and MMP2,suggesting that TRIM21 is involved in the process of vascular remodeling following vascular injury.2.TRIM21 knockout could inhibit the proliferation and migration of vascular smooth muscle cells following arterial injury,reduce the level of oxidative stress and inflammatory response,and mitigate the proliferation of vascular intima.3.TRIM21 knockout inhibited LPS-induced VSMCs cell proliferation,migration,oxidative stress and inflammatory response.4.TRIM21 knockout inhibited LPS-induced NF-κB signaling pathway activation in VSMCs.5.Inhibition of NF-κB pathway significantly reduced the TRIM21overexpression-induced oxidative stress,inflammatory response,proliferation and migration of LPS-induced VSMCs cells ConclusionTTRIM21 affects the inflammatory response,proliferation and migration ability of VSMCs after arterial injury through the NF-κB pathway,and thereby affecting vascular remodeling.