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Abstract: Inflammatory reactions driven by an accumulation in the intima of immune-inflammatory cells and focal lipid depositions are the hallmarks of atherogenesis. It is commonly accepted that immune-inflammatory cell accumulation and lipid deposition are associated with the very earlier stage of atherosclerosis but no study has yet focused on the determination of quantitative values of this association. The present study examined correlations between lipid deposition, immune-inflammatory cell content and major histocompatibility complex (MHC) class II molecule HLA-DR expression in diffuse intimal thickening (DIT), which is thought to represent the earliest macroscopic manifestation of atherosclerosis. In parallel consecutive tissue sections of DIT, lipids were examined by chromatographic analysis (including triglycerides, cholesteryl esters, free cholesterol and phospholipids), histochemically, using Oil Red O staining, and by electron microscopy. Immune-inflammatory cells and HLA-DR expression were examined immunohistochemically in consecutive sections of the same tissue specimens. The study revealed that lipids exhibited a non-uniform distribution throughout the intima. In the juxtaluminal sublayer, lipids were localized both intracellularly and extracellularly, whereas in the juxtamedial musculoelastic sublayer, lipids were present predominantly along elastic fibers. Lipid deposits were found to positively correlate with HLA-DR expression (r =0.79; p <0.001). The study also identified a positive correlation between lipid deposition and immune-inflammatory cell content but the correlation values varied between different sublayers of the tunica intima. The correlation between lipid deposition and immune-inflammatory cell content in the juxtaluminal sublayer of the intima was notably stronger (r =0.69; p <0.001) than in the juxtamedial musculoelastic layer (r =0.28; p <0.001). The findings of the present study support a view that lipid accumulation in the intima plays a role in the initiation of inflammatory reaction and that at the pre-lesional stage in the development of atherosclerosis, lipid-associated immune cell activation might occur primarily in the juxtaluminal portion of the intima. [Copyright &y& Elsevier]

Pericytes are multipotent mesenchymal stromal cells playing an active role in angiogenesis, vessel stabilisation, maturation, remodelling, blood flow regulation and are able to trans-differentiate into other cells of the mesenchymal lineage. In this review, we summarised recent data demonstrating that pericytes play a key role in the pathogenesis and development of atherosclerosis (AS). Pericytes are involved in lipid accumulation, inflammation, growth, and vascularization of the atherosclerotic plaque. Decreased pericyte coverage, endothelial and pericyte dysfunction is associated with intraplaque angiogenesis and haemorrhage, calcification and cholesterol clefts deposition. At the same time, pericytes can be used as a novel therapeutic target to promote vessel maturity and stability, thus reducing plaque vulnerability. Finally, we discuss recent studies exploring effective AS treatments with pericyte-mediated anti-atherosclerotic, anti-inflammatory and anti-apoptotic effects. [ABSTRACT FROM AUTHOR]

Pericytes are mural vascular cells covering microvascular capillaries, where they contribute to the formation, maturation, maintenance, stabilisation and remodelling of vasculature. They actively interact and communicate with other cells to maintain the capillary structural integrity, vascular permeability and blood flow. Pericytes are crucial participants in the physiological and pathological processes of cardiovascular disease. In this review, we summarise recent data regarding pericyte metabolism, trans-differentiation, angiogenesis and immunomodulation in connection with different cardiovascular pathologies. Further, we discuss an application of pericytes as a new cell therapy approach to treat coronary artery disease, congenital heart disease, atherosclerotic plaques calcification and calcific valvular heart disease in different in vivo animal models and in vitro studies. Also, we discuss different methods and pharmacological therapies for CVDs treatment with pericyte-mediated effects. Finally, we present a comprehensive overview of the role of pericytes in CVDs and as a pharmacological target for different novel drugs and techniques and highlight the potential application of pericytes to treat CVDs. • Pericytes constriction reduces microvascular blood flow after ischaemia (no-reflow). • Pericytes constriction may be regulated with IPC technique and pharmacologically. • Pericytes transplantation ameliorates tissue remodelling after myocardial infarction. • Pericytes cellularize prosthetic materials, thus improving grafts and valve integration. [ABSTRACT FROM AUTHOR]