Cardiovascular disease: C-reactive protein and the inflammatory disease paradigm: HMG-CoA reductase inhibitors, alpha-tocopherol, red yeast rice, and olive oil polyphenols. A review of the literature

Abstract

The current understanding of the origin of atherosclerosis is that of an inflammatory process that involves the acute phase response -an innate biological response to a disturbance in homeostasis -infection, inflammation, tissue injury, neoplasm, or immune disturbance. The activation of the acute phase response, signaled by interleukin-6, produces proteins (fibrinogen, C-reactive protein (CRP), serum amyloid A) that lead to inflammatory reactions. The tissues themselves contain elevated levels of acute phase proteins and cytokines resulting in a localized inflammatory effect. Localized inflammatory responses in the intimal layer of the arterial wall have been shown to be responsible for many of the aspects of intimal thickening and plaque disruption, leading to acute cardiovascular events. The predictive value of plasma C-reactive protein as a risk factor for cardiovascular events has led some researchers to support the use of CRP as a main cardiovascular risk assessment tool, along with total cholesterol:HDL ratios and homocysteine levels. The ability of HMG-CoA reductase inhibitors to lower C-reactive protein levels has recently brought into question the mechanisms of action of the statin drugs. Because these medications lower incidences of acute cardiovascular events as well as decreasing morbidity and mortality well before the effects of lowered LDL cholesterol can be expected to occur, questions have been asked about whether they may work independently of LDL-lowering mechanisms. Red yeast rice contains a naturally-occurring statin (lovastatin) as well as other cholesterol-lowering compounds, some with antioxidant effects. Alpha-tocopherol also significantly lowers CRP levels in diabetics and nondiabetics, and minimizes other aspects of the acute phase response and inflammatory damage involved in atherosclerosis. This may account for alpha-tocopherol's positive effect on cardiovascular morbidity and mortality. Finally, polyphenolic compounds present in virgin olive oil also have anti-inflammatory and antioxidative effects in cardiovascular disease. The phenolic compounds in virgin olive oil may explain some of the protective effects found in epidemiological studies.