The endothelium: influencing vascular smooth muscle in many ways

Abstract

The endothelium, although only a single layer of cells lining the vascular and lymphatic systems, contributes in multiple ways to vascular homeostasis. Subsequent to the 1980 report by Robert Furchgott and John Zawadzki, there has been a phenomenal increase in our knowledge concerning the signalling molecules and pathways that regulate endothelial - vascular smooth muscle communication. It is now recognised that the endothelium is not only an important source of nitric oxide (NO), but also numerous other signalling molecules, including the putative endothelium-derived hyperpolarizing factor (EDHF), prostacyclin (PGI(2)), and hydrogen peroxide (H(2)O(2)), which have both vasodilator and vasoconstrictor properties. In addition, the endothelium, either via transferred chemical mediators, such as NO and PGI(2), and (or) low-resistance electrical coupling through myoendothelial gap junctions, modulates flow-mediated vasodilatation as well as influencing mitogenic activity, platelet aggregation, and neutrophil adhesion. Disruption of endothelial function is an early indicator of the development of vascular disease, and thus an important area for further research and identification of potentially new therapeutic targets. This review focuses on the signalling pathways that regulate endothelial - vascular smooth muscle communication and the mechanisms that initiate endothelial dysfunction, particularly with respect to diabetic vascular disease.

Mitochondrial Ion Channels/Transporters as Sensors and Regulators of Cellular Redox Signaling

“…Redox signaling has also gained recognition for its role in mediating diverse tissue-specific cellular functions across a wide range of cell types. For instance, redox signaling regulates muscle contraction/relaxation (145,155,169,178), insulin secretion from pancreatic beta cells (191), metabolic cycles in liver (137), self-renewal and differentiation in stem cells (98), and T-cell homeostasis (67,100,120).…”

Endothelial Cells Direct Mesenchymal Stem Cells Toward a Smooth Muscle Cell Fate

“…In adult blood vessels, it is well established that endothelial cells impact vascular smooth muscle cell function by governing their contractile response [7,8]. Endothelial cellderived factors like nitric oxide and endothelin are perceived by surrounding smooth muscle cells, which alters vascular reactivity.…”

Evaluation of Ginsenoside Rg1 as a Potential Antioxidant for Preventing or Ameliorating Progression of Atherosclerosis

“…It is synthesized by NOS enzymes in which NO and L-citrulline are two products, and L-arginine is the substrate [14]. Within the vasculature, NO induces vasodilatation, prevents platelet adhesion to endothelial cells, inhibits platelet aggregation, controls smooth muscle cell proliferation and migration, maintains an endothelial cell barrier function, and regulates apoptosis [15]. At higher levels, O 2− reacts with NO to form a cytotoxic peroxynitrite (ONOO−) and decrease NO production, which plays a critical role in endothelial cell damage [16].…”