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[Protective effect of insulin-like growth factor-1 on vascular endothelial function in hypercholesterolemia and the

Shaokui Ji1, Qilin Ma, Xiuju Luo

  • 1Department of Cardiology, Xiangya Hospital, Central South University, Changsha 410008,China.

Zhong Nan Da Xue Xue Bao. Yi Xue Ban = Journal of Central South University. Medical Sciences
|February 15, 2013
PubMed

Insights

Lower serum insulin-like growth factor-1 (IGF-1) is linked to vascular endothelial dysfunction in hypercholesterolemia. IGF-1 protects endothelial cells from damage and senescence, potentially via the DDAH/ADMA pathway.

Area of Science:

  • Cardiovascular Research
  • Endocrinology
  • Vascular Biology

Background:

  • Hypercholesterolemia is associated with impaired vascular endothelial function.
  • Insulin-like growth factor-1 (IGF-1) plays a role in vascular health.
  • The precise mechanisms linking IGF-1 to endothelial dysfunction in hypercholesterolemia require elucidation.

Purpose of the Study:

  • To investigate the relationship between serum IGF-1 levels and vascular endothelial function in hypercholesterolemia patients.
  • To explore the underlying mechanisms, including the role of asymmetric dimethylarginine (ADMA) and nitric oxide (NO).
  • To assess the protective effects of IGF-1 on endothelial cells in vitro.

Main Methods:

  • Serum analysis of IGF-1, ADMA, NO, and nitric oxide synthase (NOS) activity in 25 hypercholesterolemia patients and controls.
  • In vitro endothelial cell injury model using oxidized low-density lipoprotein (ox-LDL) on human umbilical vein endothelial cells (HUVECs).
  • Assessment of ADMA, NOS, NO, dimethylarginine dimethylamine hydrolase (DDAH) activity, and cellular senescence.

Main Results:

  • Hypercholesterolemia patients exhibited reduced flow-mediated arterial diastolic function (FMD), lower IGF-1 and NO, and elevated ADMA levels.
  • Serum IGF-1 positively correlated with FMD, while ADMA negatively correlated with FMD.
  • Ox-LDL induced endothelial cell senescence and dysfunction, which was significantly attenuated by IGF-1 treatment.

Conclusions:

  • Decreased serum IGF-1 may contribute to vascular endothelial dysfunction in hypercholesterolemia.
  • IGF-1 demonstrates a protective effect against ox-LDL-induced endothelial cell senescence.
  • The protective mechanism of IGF-1 likely involves the regulation of the DDAH/ADMA pathway.
Abstract

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