Connexin 43 expressed in endothelial cells modulates monocyte‑endothelial adhesion by regulating cell adhesion proteins.
Adhesion between circulating monocytes and vascular endothelial cells is a key initiator of atherosclerosis. In our previous studies, it was demonstrated that the expression of connexin (Cx)43 in monocytes modulates cell adhesion, however, the effects of the expression of Cx43 in endothelial cells remains to be elucidated. Therefore, the present study investigated the role of the expression of Cx43 in endothelial cells in the process of cell adhesion. A total of four different methods with distinct mechanisms were used to change the function and expression of Cx43 channels in human umbilical vein endothelial cells: Cx43 channel inhibitor (oleamide), enhancer (retinoic acid), overexpression of Cx43 by transfection with pcDNA‑Cx43 and knock‑down of the expression of Cx43 by small interfering RNA against Cx43. The results indicated that the upregulation of the expression of Cx43 enhanced monocyte‑endothelial adhesion and this was markedly decreased by downregulation of Cx43. This mechanism was associated with Cx43‑induced expression of vascular cell adhesion molecule‑1 and intercellular cell adhesion molecule‑1. The effects of Cx43 in endothelial cells was independent of Cx37 or Cx40. These experiments suggested that local regulation of endothelial Cx43 expression within the vasculature regulates monocyte‑endothelial adhesion, a critical event in the development of atherosclerosis and other inflammatory pathologies, with baseline adhesion set by the expression of Cx43. This balance may be crucial in controlling leukocyte involvement in inflammatory cascades.
Department of Anesthesiology, The Third Affiliated Hospital of Sun Yat‑Sen University, Guangzhou, Guangdong 510630, P.R. China.
Dongdong
D
Yuan
Department of Anesthesiology, The Third Affiliated Hospital of Sun Yat‑Sen University, Guangzhou, Guangdong 510630, P.R. China.
Guoliang
G
Sun
Department of Anesthesiology, The Third Affiliated Hospital of Sun Yat‑Sen University, Guangzhou, Guangdong 510630, P.R. China.
Rui
R
Zhang
Department of Anesthesiology, The Third Affiliated Hospital of Sun Yat‑Sen University, Guangzhou, Guangdong 510630, P.R. China.
Chenfang
C
Luo
Department of Anesthesiology, The Third Affiliated Hospital of Sun Yat‑Sen University, Guangzhou, Guangdong 510630, P.R. China.
Mian
M
Ge
Department of Anesthesiology, The Third Affiliated Hospital of Sun Yat‑Sen University, Guangzhou, Guangdong 510630, P.R. China.
Gangjian
G
Luo
Department of Anesthesiology, The Third Affiliated Hospital of Sun Yat‑Sen University, Guangzhou, Guangdong 510630, P.R. China.
Ziqing
Z
Hei
D002448:Cell Adhesion; D015815:Cell Adhesion Molecules / Q000378:metabolism; D002478:Cells, Cultured; D018031:Connexin 43 / Q000378:metabolism*; D017630:Connexins / Q000378:metabolism; D017629:Gap Junctions / Q000378:metabolism; D061307:Human Umbilical Vein Endothelial Cells / Q000502:physiology*; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000378:metabolism; D009000:Monocytes / Q000502:physiology*; D019010:Vascular Cell Adhesion Molecule-1 / Q000378:metabolism; D000097006:Gap Junction alpha-4 Protein
D015815:Cell Adhesion Molecules; D018031:Connexin 43; D017630:Connexins; D018799:Intercellular Adhesion Molecule-1; D019010:Vascular Cell Adhesion Molecule-1; D000097006:Gap Junction alpha-4 Protein