title: Effect of thymosin beta 4 in the presence of up-regulation of the insulin-like growth factor-1 signaling pathway on high-glucose-exposed vascular endothelial cells.
abstract: Thymosin beta 4 (Tβ4), which regulates vascular cell growth, can ameliorate some of the problems associated with diabetes. However, the precise signaling mechanisms by which Tβ4 protects against hyperglycemia-induced damage to endothelial cells have not been investigated in detail. Thus, the aim of this study was to elucidate the role of Tβ4 in diabetes and the possible involvement of insulin-like growth factor-1 (IGF-1), which affects cellular survival, metabolism, and glucose homeostasis in high-glucose (HG)-injured human umbilical vein endothelial cells (HUVECs). Immunoblotting assays revealed that under HG blockade conditions, Tβ4 did not alter the insulin-signaling pathway, but induced overexpression of IGF-1 protein, leading to activation of factors in alternative signaling pathway. Small interfering RNA of Tβ4 and IGF-1 were studied to clarify relationship between Tβ4 and IGF-1. These findings suggest that IGF-1 induction by Tβ4 ameliorates the damage in HG-injured HUVECs which manifest as diabetic vascular disorder.
authors.affiliation: Department of Laboratory Animal Medicine, College of Veterinary Medicine, Chonbuk National University, Jeonju, Jeonbuk 561-156, Republic of Korea.
authors.forename: Sokho
authors.initials: S
authors.lastname: Kim
authors.affiliation: Department of Laboratory Animal Medicine, College of Veterinary Medicine, Chonbuk National University, Jeonju, Jeonbuk 561-156, Republic of Korea. Electronic address: jkwon@chonbuk.ac.kr.
authors.forename: Jungkee
authors.initials: J
authors.lastname: Kwon
mesh_terms: D002470:Cell Survival / Q000187:drug effects; D042783:Endothelial Cells / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D005947:Glucose / Q000494:pharmacology*; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects; D013947:Thymosin / Q000494:pharmacology*; D015854:Up-Regulation; D000099201:Thymosin beta(4)
chemical_list: D005947:Glucose; D007334:Insulin-Like Growth Factor I; D013947:Thymosin; D000099201:Thymosin beta(4); C583557:IGF1 protein, human
keywords: Diabetes; Hyperglycemia; Insulin-like growth factor-1; Thymosin beta 4; Vascular disorder