Atherosclerosis: orchestrating cells and biomolecules involved in its activation and inhibition

The term atherosclerosis refers to the condition of deposition of lipids and other substances in and on the artery walls, called as plaque that restricts the normal blood flow. The plaque may be stable or unstable in nature. Unstable plaque can burst and trigger clot formation adding further adversities. The process of plaque formation involves various stages including fatty streak, intermediate or fibro-fatty lesion and advanced lesion. The cells participating in the formation of atherosclerotic plaque include endothelial cells, vascular smooth muscle cells (VSMC), monocytes, monocytes derived macrophages, macrophages and dendritic cells and regulatory T cells (T_REG). The role of a variety of cytokines and chemokines have been studied which either help in progression of atherosclerotic plaque or vice versa. The cytokines involved in atherosclerotic plaque formation include IL-1, IL-2, IL-3, IL-4, IL-5, IL-6, IL-9, IL-10, IL-12, IL-13, IL-15, IL-17, IL-18, IL-20, IL-25, IL-27, IL-33, IL-37, TNF-α, TGF-β and IFN-γ; whereas amongst the chemokines (family of small cytokines) are CCL2, CCL3, CXCL4, CCL5, CXCL1, CX3CL1, CCL17, CXCL8, CXCL10, CCL20, CCL19 and CCL21 and macrophage migration-inhibitory factor. These are involved in the atherosclerosis advancements, whereas the chemokine CXCL12 is play atheroprotective roles. Apart this, contradictory functions have been documented for few other chemokines such as CXCL16. Since the cytokines and chemokines are amongst the key molecules involved in orchestrating the atherosclerosis advancements, targeting them might be an effective strategy to encumber the atherosclerotic progression. Blockage of cytokines and chemokines via the means of broad-spectrum inhibitors, neutralizing antibodies, usage of decoy receptors or RNA interference have been proved to be useful intervention against atherosclerosis.