Identification of Key Genes Associated with Endothelial Cell Dysfunction in Atherosclerosis Using Multiple Bioinformatics Tools

Atherosclerosis is the most notable cardiovascular disease, the latter being the main cause of death globally. Endothelial cell dysfunction plays a major role in the pathogenesis of atherosclerosis. However, it is currently unclear which genes are involved between endothelial cell dysfunction and atherosclerosis. This study was aimed at identifying these genes. Based on the GSE83500 dataset, the quantification of endothelial cell function was conducted using single-sample gene set enrichment analysis; the coexpression modules were conducted using weighted correlation network analysis. After building module-trait relationships, tan and yellow modules were regarded as hub modules. 10 hub genes from each hub module were identified by the protein-protein interaction network analysis. The key genes (RAB5A, CTTN, ITGB1, and MMP9) were obtained by comparing the expression differences of the hub gene between atherosclerotic and normal groups from the GSE28829 and GSE43292 datasets, respectively. ROC analysis showed the diagnostic value of key genes. Moreover, the differential expression of key genes in normal and atherosclerotic aortic walls was verified. In vitro, we establish a model of ox-LDL-injured endothelial cells and transfect RAB5A overexpression and shRNA plasmids. The results showed that overexpression of RAB5A ameliorates the proliferation and migration function of ox-LDL-injured endothelial cells, including the ability of tubule formation. It was speculated that the interferon response, Notch signaling pathways, etc. were involved in this function of RAB5A by using gene set variation analysis. With the multiple bioinformatics analysis methods, we detected that yellow and tan modules are related to the abnormal proliferation and migration of endothelial cells associated with atherosclerosis. RAB5A, CTTN, ITGB1, and MMP9 can be used as potential targets for therapy and diagnostic markers. In vitro, overexpression of RAB5A can ameliorate the proliferation and migration function of ox-LDL-injured endothelial cells, and the possible molecules involved in this process were speculated.

Sonic Hedgehog Improved Endothelial Cell Dysfunction and Attenuated The Development of Atherosclerosis In Mice

Sonic hedgehog (Shh), an evolutionally-highly conserved morphological factor whose maturation, transportation and function were closely related to cholesterol. Shh played an important role in maintaining adult coronary vasculature homeostasis. It not only induced angiogenesis to improve myocardial infarction but also inhibited ox-LDL induced endothelial apoptosis. However, the role of Shh in endothelial cell injury have not been fully elucidated. Here, we shown Shh induced nitric oxide (NO) release and endothelial nitric oxide synthase (eNOS) synthesis, which improved endothelial cell dysfunction and inhibited atherosclerotic plaque. In vivo, Shh reduced the plaque lesion in high fat diet (HFD) induced ApoE-/- mice. In endothelial cell, Shh improved NO and eNOS mRNA expression and inhibited intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) mRNA expression. In contrast, knockdown of Shh inhibited eNOS and NO level and induced ICAM-1 and VCAM-1. In conclusion, we found that Shh has anti-inflammation and improved endothelial cell injury consequently attenuated the development of atherosclerosis.

Linking In Vitro Models of Endothelial Dysfunction with Cell Senescence

Endothelial cell dysfunction is the principal cause of several cardiovascular diseases that are increasing in prevalence, healthcare costs, and mortality. Developing a standardized, representative in vitro model of endothelial cell dysfunction is fundamental to a greater understanding of the pathophysiology, and to aiding the development of novel pharmacological therapies. We subjected human umbilical vein endothelial cells (HUVECs) to different periods of nutrient deprivation or increasing doses of H2O2 to represent starvation or elevated oxidative stress, respectively, to investigate changes in cellular function. Both in vitro cellular models of endothelial cell dysfunction-associated senescence developed in this study, starvation and oxidative stress, were validated by markers of cellular senescence (increase in β-galactosidase activity, and changes in senescence gene markers SIRT1 and P21) and endothelial dysfunction as denoted by reductions in angiogenic and migratory capabilities. HUVECs showed a significant H2O2 concentration-dependent reduction in cell viability (p < 0.0001), and a significant increase in oxidative stress (p < 0.0001). Furthermore, HUVECs subjected to 96 h of starvation, or exposed to concentrations of H2O2 of 400 to 1000 μM resulted in impaired angiogenic and migratory potentials. These models will enable improved physiological studies of endothelial cell dysfunction, and the rapid testing of cellular efficacy and toxicity of future novel therapeutic compounds.

Early Ascorbic Acid Administration Prevents Vascular Endothelial Cell Damage In Septic Mice

Ascorbic acid (AsA) therapy for sepsis is thought to have a protective effect on vascular endothelial cells, but the effect of AsA therapy on endothelial cell dysfunction over time and the appropriate timing for AsA administration to demonstrate efficacy is unclear. Septic mice, induced by cecal ligation and puncture (CLP), were examined for the effect of AsA administration (200 mg/kg) on vascular endothelial cell dysfunction at two administration timings: early group (AsA was administered immediately after CLP) and late group (AsA was administered 12 h after CLP). Survival rates were compared between the early and late administration groups, and vascular endothelial cell damage, indicated by the dihydrobiopterin/tetrahydrobiopterin ratio, serum syndecan-1, and endothelial nitric oxide synthase, as well as liver damage, were examined. The early group showed significantly improved survival compared to the non-treatment group (p < 0.05), while the late group showed no improved survival compared to the non-treatment group. Early AsA administration suppressed damage to the vascular endothelial system and liver compared to the non-treatment group. In septic mice, early AsA administration immediately after CLP may have protective effects on vascular endothelial cells, resulting in reduced organ dysfunction and improved survival.