The Mechanism Of Selenium Regulating The Permeability Of Vascular Endothelial Cells Through Selenoprotein O

Selenium(Se),as an essential mineral element in many organisms,is important for animal and human health and can cause many diseases when insufficient intake of selenium.Selenocysteine(Sec)is synthesized and inserted into selenoprotein(Sel)by recoding the stop codon UGA into the Sec codon,and is an essential amino acid for various selenoproteins that perform physiological functions.Twenty-four selenoproteins have been identified in mice,but research on selenoprotein O(Sel O)is limited.Vascular diseases are a serious and common group of diseases,which are closely related to vascular pathological damage,and selenoproteins play an important role in the development of vascular diseases.In this experiment,we established mouse models with different concentrations of selenium treatment,and constructed in vitro models with different concentrations of selenium treatment and Sel O interference models through vascular endothelial cells(HUVEC),and then investigated the regulatory mechanism of the effect of Sel O on vascular endothelial cell permeability.In vivo tests were divided into: selenium deficient group(Low Se Group,L group,no selenium added to the diet),normal selenium group(Control Group,C group,diet containing 0.18 mg/kg of selenium)and high selenium group(High Se Group,H group,diet containing 0.6 mg/kg of selenium).Histopathology was used to evaluate the extent of vascular damage and the effects of vascular endothelial cell integrity,vascular interendothelial cell junction structure and vascular permeability barrier.Immunohistochemical methods were used to detect the expression of adhesion spot protein(vinculin),a key factor for adhesion spot formation,in blood vessels.Western Blot and q RT-PCR were applied to detect the expression levels of adhesion spot protein formation factors vinculin,talin and paxillin,the expression of the junctional effector molecules connexin,JAM-A,claudin-1,E-Cadherin and N-Cadherin in the vasculature and the ZO-1 signaling pathway expression levels of ZO-1,rock,rho GEF,cingulin,and MLC-2.The isolation tests were divided into: selenium-deficient group(Low Se Group,L group,cultured with 0 ng/m L selenocysteine in medium),Middle Se Group(M group,cultured with 5 ng/m L selenocysteine in medium),selenium-supplemented group(High Se Group,H group,cultured with 10ng/m L selenocysteine in medium),si RNA-NC group(negative control group transfected with si RNA-Sel O cultured in normal medium),si RNA-L group(transfected with si RNA-Sel O treated group cultured in 0 ng/m L selenocysteine medium),si RNA-M group(transfected with si RNA-Sel O treated group cultured in 5 ng/m L selenocysteine medium),and si RNA-H group(transfected with si RNA-Sel O treated group cultured in 5 ng/m L selenocysteine medium).(transfected si RNA-Sel O treatment group was cultured with 10 ng/m L selenocysteine medium)and si RNA-H group(transfected si RNA-Sel O treatment group was cultured with 10 ng/m L selenocysteine medium).Western Blot and q RT-PCR were used to detect the expression levels of adhesion plaque protein-forming factors vinculin,talin and paxillin,the expression of the linkage effector molecules connexin,JAM-A,claudin-1,E-Cadherin and N-Cadherin in blood vessels,and the ZO-1 signaling pathway ZO-1,rock,rho GEF,cingulin,and MLC-2 expression levels.The results found that.(1)In selenium-deficient mice,vascular structure is damaged,vascular integrity is disrupted,intercellular connections are impaired,and vascular permeability is increased.(2)The expression levels of the adhesion plaque proteins vinculin,talin and paxillin were reduced in selenium deficiency,impairing intercellular junctions in the vascular endothelium.The expression of connexin,claudin-1 and E-Cadherin,the junctional effector molecules in the vasculature was decreased,the expression of JAM-A and N-Cadherin was increased,and the expression of ZO-1,rock,rho GEF,cingulin and MLC-2,the ZO-1 signaling pathway,was decreased.(3)Among the 24 selenoproteins present in mice screened for varying selenium concentrations,the selenoprotein Sel O showed the most significant changes in vascular tissue and a potential link between Sel O and vascular intercellular junction effectors was determined by IBM SPSS Statistics 25.(4)Construction of a Sel O knockdown HUVEC model revealed reduced expression levels of the adhesion spot proteins vinculin,talin and paxillin,reduced expression of the linkage effector molecules connexin,claudin-1 and E-Cadherin,increased expression of JAM-A and N-Cadherin,and reduced expression of the ZO-1 signaling pathways ZO-1,rock,rho GEF,cingulin,and MLC-2 expression was decreased.To determine the regulatory relationship between Sel O and intervascular endothelial cell junctions.The results showed that selenium deficiency led to decreased expression of Sel O,which inhibited the expression of adhesion plaque proteins vinculin,talin,and paxillin,inhibited adhesion plaque formation,and affected the expression of interendothelial cell junctions(including gap junctions,tight junctions,and adhesion junctions)and the ZO-1 signaling pathway,resulting in impaired vascular endothelial cell integrity and decreased vascular adhesion plaque protein content The expression of ZO-1 signaling pathway leads to impaired vascular endothelial cell integrity and reduced vascular adhesion plaque protein content.