(+)-Catechin Attenuates Multiple Atherosclerosis-Associated Processes In Vitro, Modulates Disease-Associated Risk Factors in C57BL/6J Mice and Reduces Atherogenesis in LDL Receptor Deficient Mice by Inhibiting Inflammation and Increasing Markers of Plaque Stability.

SCOPE: A prospective study of 34492 participants shows an inverse association between (+)-catechin intake and coronary heart disease. The effects of (+)-catechin on atherosclerosis and associated risk factors are poorly understood and are investigated. METHODS AND RESULTS: (+)-Catechin attenuates reactive oxygen species production in human macrophages, endothelial cells and vascular smooth muscle cells, chemokine-driven monocytic migration, and proliferation of human macrophages and their expression of several pro-atherogenic genes. (+)-Catechin also improves oxidized LDL-mediated mitochondrial membrane depolarization in endothelial cells and attenuates growth factor-induced smooth muscle cell migration. In C57BL/6J mice fed high fat diet (HFD) for 3 weeks, (+)-catechin attenuates plasma levels of triacylglycerol and interleukin (IL)-1ß and IL-2, produces anti-atherogenic changes in liver gene expression, and reduces levels of white blood cells, myeloid-derived suppressor cells, Lin- Sca+ c-Kit+ cells, and common lymphoid progenitor cells within the bone marrow. In LDL receptor deficient mice fed HFD for 12 weeks, (+)-catechin attenuates atherosclerotic plaque burden and inflammation with reduced macrophage content and increased markers of plaque stability; smooth muscle cell and collagen content. CONCLUSION: This study provides novel, detailed insights into the cardio-protective actions of (+)-catechin together with underlying molecular mechanisms and supports further assessments of its beneficial effects in human trials.

Protective effects of a unique combination of nutritionally active ingredients on risk factors and gene expression associated with atherosclerosis in C57BL/6J mice fed a high fat diet.

Atherosclerosis, an inflammatory disorder of the vasculature and the underlying cause of cardiovascular disease, is responsible for one in three global deaths. Consumption of active food ingredients such as omega-3 polyunsaturated fatty acids, flavanols and phytosterols has many beneficial effects on cardiovascular disease. However, their combined actions on the risk factors for atherosclerosis remains poorly understood. We have previously shown that a formulation containing each of these active components at physiologically relevant doses modulated several monocyte/macrophage processes associated with atherosclerosis in vitro, including inhibition of cytokine-induced pro-inflammatory gene expression, chemokine-driven monocyte migration, expression of M1 phenotype markers, and promotion of cholesterol efflux. The objectives of the present study were to investigate whether the protective actions of the formulation extended in vivo and to delineate the potential underlying mechanisms. The formulation produced several favourable changes, including higher plasma levels of HDL and reduced levels of macrophages and myeloid-derived suppressor cells in the bone marrow. The mRNA expression of liver-X-receptor-α, peroxisome proliferator-activated receptor-γ and superoxide dismutase-1 was induced in the liver and that of interferon-γ and the chemokine (C-X-C motif) ligand 1 decreased, thereby suggesting the potential mechanisms for many beneficial effects. Other changes were also observed such as increased plasma levels of triglycerides and lipid peroxidation that may reflect potential activation of brown fat. This study provides new insights into the protective actions and the potential underlying mechanisms of the formulation in vivo, particularly in relation to risk factors together with changes in systemic inflammation and hepatic lipid alterations associated with atherosclerosis and metabolic syndrome, and supports further assessments in human trials.