Cellular and Oxidative Mechanisms Associated with Interleukin-6 Signaling in the Vasculature

Abstract

Reactive oxygen species, particularly superoxide, promote endothelial dysfunction and alterations in vascular structure. It is increasingly recognized that inflammatory cytokines, such as interleukin-6 (IL-6), contribute to endothelial dysfunction and vascular hypertrophy and fibrosis. IL-6 is increased in a number of cardiovascular diseases, including hypertension. IL-6 is also associated with a higher incidence of future cardiovascular events and all-cause mortality. Both immune and vascular cells produce IL-6 in response to a number of stimuli, such as angiotensin II. The vasculature is responsive to IL-6 produced from vascular and non-vascular sources via classical IL-6 signaling involving a membrane-bound IL-6 receptor (IL-6R) and membrane-bound gp130 via Jak/STAT as well as SHP2-dependent signaling pathways. IL-6 signaling is unique because it can also occur via a soluble IL-6 receptor (sIL-6R) which allows for IL-6 signaling in tissues that do not normally express IL-6R through a process referred to as IL-6 trans-signaling. IL-6 signaling mediates a vast array of effects in the vascular wall, including endothelial activation, vascular permeability, immune cell recruitment, endothelial dysfunction, as well as vascular hypertrophy and fibrosis. Many of the effects of IL-6 on vascular function and structure are representative of loss or reductions in nitric oxide (NO) bioavailability. IL-6 has direct effects on endothelial nitric oxide synthase activity and expression as well as increasing vascular superoxide, which rapidly inactivates NO thereby limiting NO bioavailability. The goal of this review is to highlight both the cellular and oxidative mechanisms associated with IL-6-signaling in the vascular wall in general, in hypertension, and in response to angiotensin II.

Role of Cystic Fluid Growth Factors and Inflammatory Mediators in Pathogenesis of Polycystic Ovary Syndrome

“…There is a positive correlation between VEGF, Angiopoietin-1, IGF-1, C3and IL-18 supporting the hypothesis of their coordinated effect in folliculogenesis, angiogenesis and ovarian vasculature [26,27]. It is very clear from above data that IL-18 and C3 induced inflammatory reaction with respect to numbers, size, length and depth of cysts is reversed by IGF-1, VEGF, MMP-2 and C3 supporting the results of previous review report on inflammatory and anti-inflammatory mechanism [28].…”

Potential therapeutic effects of endothelial cells trans-differentiated from Wharton’s Jelly-derived mesenchymal stem cells on altered vascular functions in aged diabetic rat model

“…Both eNOS activity and expression are directly reduced by IL-6. IL-6 also increases vascular superoxide production, which inactivates NO promptly resulting in the reduction in NO bioavailability [34]. In other words, IL-6 can directly alter NO synthesis and bioavailability.…”

A Network Pharmacology-Based Study on Active Ingredients of Corydalis Rhizoma on Coronary Heart Disease

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