Review of OxLDL Driven Inflammatory Cell Activation

Atherosclerosis is considered to be an inflammatory disease due to the presence of macrophages and T-cells within the artery plaques. Atherosclerotic plaques contain significant levels of oxidised low density lipoprotein (oxLDL) suggesting it is a source of the observed inflammation. In this systematic review, the PubMed, Medline and Scopus databases were searched for studies on the inflammatory effects of oxLDL and therapeutic treatments intended to prevent inflammation in humans or human-derived cell lines.

Out of the 65 articles that passed through a full-text examination of the inflammatory effects of oxLDL, eight were considered suitable for inclusion in the study. Fifty studies out of 75 studies which were subjected to full-text review of anti-inflammatory agents were selected. Three out of 4 studies that measured the effect of oxLDL stimulation on interleukin (IL)-1β reported significant increase in IL-1β level, while 4 out of 6 studies that measured IL-6 reported significant increase in IL-6 level. Four out of 6 studies that measured tumour necrosis factor (TNF)-α reported significant increase in TNF-α after oxLDL stimulation, while 2 studies reported significant increase in caspase-1 activation by oxLDL. Although some of the studies on the anti-inflammatory agents demonstrated significant inhibition of inflammation, none of the anti-inflammatory agents directly targeted oxLDL immune activation. It is evident that there is an interplay between cholesterol and vascular cells in the pathogenesis of atherosclerosis, but there is a gap between the suggested effects of oxLDL in literatures and actual intrinsic effects of oxLDL on the vascular cells.