title: Far-infrared radiation inhibits proliferation, migration, and angiogenesis of human umbilical vein endothelial cells by suppressing secretory clusterin levels.
abstract: Far-infrared (FIR) radiation is known to lessen the risk of angiogenesis-related diseases including cancer. Because deficiency of secretory clusterin (sCLU) has been reported to inhibit angiogenesis of endothelial cells (EC), we investigated using human umbilical vein EC (HUVEC) whether sCLU mediates the inhibitory effects of FIR radiation. Although FIR radiation ranging 3-25μm wavelength at room temperature for 60min did not alter EC viability, further incubation in the culture incubator (at 37°C under 5% CO2) after radiation significantly inhibited EC proliferation, in vitro migration, and tube formation in a time-dependent manner. Under these conditions, we found decreased sCLU mRNA and protein expression in HUVEC and decreased sCLU protein secreted in culture medium. Expectedly, the replacement of control culture medium with the FIR-irradiated conditioned medium significantly decreased wound closure and tube formation of HUVEC, and vice versa. Furthermore, neutralization of sCLU with anti-sCLU antibody also mimicked all observed inhibitory effects of FIR radiation. Moreover, treatment with recombinant human sCLU protein completely reversed the inhibitory effects of FIR radiation on EC migration and angiogenesis. Lastly, vascular endothelial growth factor also increased sCLU secretion in the culture medium, and wound closure and tube formation of HUVEC, which were significantly reduced by FIR radiation. Our results demonstrate a novel mechanism by which FIR radiation inhibits the proliferation, migration, and angiogenesis of HUVEC, via decreasing sCLU.
authors: Department of Molecular Medicine, Ewha Womans University School of Medicine, Seoul, Republic of Korea.
authors: Soojin
authors: S
authors: Hwang
authors: Division of Physical Metrology, Korea Research Institute of Standards and Science (KRISS), Daejeon, Republic of Korea.
authors: Dong-Hoon
authors: DH
authors: Lee
authors: Department of Internal Medicine, Kyungpook National University School of Medicine, Daegu, Republic of Korea.
authors: In-Kyu
authors: IK
authors: Lee
authors: Department of Molecular Medicine, Ewha Womans University School of Medicine, Seoul, Republic of Korea.
authors: Young Mi
authors: YM
authors: Park
authors: Department of Molecular Medicine, Ewha Womans University School of Medicine, Seoul, Republic of Korea. Electronic address: inhojo@ewha.ac.kr.
authors: Inho
authors: I
authors: Jo
mesh_terms: D015153:Blotting, Western; D002465:Cell Movement / Q000528:radiation effects*; D049109:Cell Proliferation / Q000528:radiation effects*; D002470:Cell Survival / Q000528:radiation effects; D051152:Clusterin / Q000096:biosynthesis*; D017077:Culture Media, Conditioned / Q000494:pharmacology; D061307:Human Umbilical Vein Endothelial Cells / Q000378:metabolism / Q000528:radiation effects*; D006801:Humans; D007259:Infrared Rays / Q000627:therapeutic use*; D009389:Neovascularization, Pathologic / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: C495242:CLU protein, human; D051152:Clusterin; D017077:Culture Media, Conditioned
keywords: Angiogenesis; Clusterin; Endothelial cell; Far-infrared radiation