Vascular smooth muscle cells (VSMC) exhibit several growth responses to agonists that regulate their function including proliferation (hyperplasia with an increase in cell number), hypertrophy (an increase in cell size without change in DNA content), endoreduplication (an increase in DNA content and usually size), and apoptosis. Both autocrine growth mechanisms (in which the individual cell synthesizes and/or secretes a substance that stimulates that same cell type to undergo a growth response) and paracrine growth mechanisms (in which the individual cells responding to the growth factor synthesize and/or secrete a substance that stimulates neighboring cells of another cell type) are important in VSMC growth. In this review I discuss the autocrine and paracrine growth factors important for VSMC growth in culture and in vessels. Four mechanisms by which individual agonists signal are described: direct effects of agonists on their receptors, transactivation of tyrosine kinase-coupled receptors, generation of reactive oxygen species, and induction/secretion of other growth and survival factors. Additional growth effects mediated by changes in cell matrix are discussed. The temporal and spatial coordination of these events are shown to modulate the environment in which other growth factors initiate cell cycle events. Finally, the heterogeneous nature of VSMC developmental origin provides another level of complexity in VSMC growth mechanisms.

https://www.physiology.org/doi/pdf/10.1152/physrev.2001.81.3.999

Vascular Smooth Muscle Growth: Autocrine Growth Mechanisms

Endothelial cells are important constituents of blood vessels that play critical roles in cardiovascular homeostasis by regulating blood fluidity and fibrinolysis, vascular tone, angiogenesis, monocyte/leukocyte adhesion, and platelet aggregation. The normal vascular endothelium is taken as a gatekeeper of cardiovascular health, whereas abnormality of vascular endothelium is a major contributor to a plethora of cardiovascular ailments, such as atherosclerosis, aging, hypertension, obesity, and diabetes. Endothelial dysfunction is characterized by imbalanced vasodilation and vasoconstriction, elevated reactive oxygen species (ROS), and proinflammatory factors, as well as deficiency of nitric oxide (NO) bioavailability. The occurrence of endothelial dysfunction disrupts the endothelial barrier permeability that is a part of inflammatory response in the development of cardiovascular diseases. As such, abrogation of endothelial cell activation/inflammation is of clinical relevance. Recently, hydrogen sulfide (H2S), an entry as a gasotransmitter, exerts diverse biological effects through acting on various targeted signaling pathways. Within the cardiovascular system, the formation of H2S is detected in smooth muscle cells, vascular endothelial cells, and cardiomyocytes. Disrupted H2S bioavailability is postulated to be a new indicator for endothelial cell inflammation and its associated endothelial dysfunction. In this review, we will summarize recent advances about the roles of H2S in endothelial cell homeostasis, especially under pathological conditions, and discuss its putative therapeutic applications in endothelial inflammation-associated cardiovascular disorders.

/pdf/role-of-endothelial-dysfunction-in-cardiovascular-diseases-14a8f85h0z.pdf

Role of Endothelial Dysfunction in Cardiovascular Diseases: The Link Between Inflammation and Hydrogen Sulfide

The chemokine receptor CXCR4 and its ligand CXCL12 play an important homeostatic function by mediating the homing of progenitor cells in the bone marrow and regulating their mobilization into peripheral tissues upon injury or stress. Although the CXCL12/CXCR4 interaction has long been regarded as a monogamous relation, the identification of the pro-inflammatory chemokine macrophage migration inhibitory factor (MIF) as an important second ligand for CXCR4, and of CXCR7 as an alternative receptor for CXCL12, has undermined this interpretation and has considerably complicated the understanding of CXCL12/CXCR4 signaling and associated biological functions. This review aims to provide insight into the current concept of the CXCL12/CXCR4 axis in myocardial infarction (MI) and its underlying pathologies such as atherosclerosis and injury-induced vascular restenosis. It will discuss main findings from in vitro studies, animal experiments and large-scale genome-wide association studies. The importance of the CXCL12/CXCR4 axis in progenitor cell homing and mobilization will be addressed, as will be the function of CXCR4 in different cell types involved in atherosclerosis. Finally, a potential translation of current knowledge on CXCR4 into future therapeutical application will be discussed.

/pdf/the-cxcl12-cxcr4-chemokine-ligand-receptor-axis-in-1kubmhronc.pdf

The CXCL12/CXCR4 chemokine ligand/receptor axis in cardiovascular disease

Extracellular collagens modulate the rate of platelet activation and thereby markedly influence hemostasis and thrombosis Platelet receptors for collagens, such as the integrin alpha(2)beta(1), platelet glycoprotein (GP) VI or, indirectly, the GPIb complex, are unexploited targets of pharmacological control, and polymorphisms of these receptors have recently become factored into the genetic risk for thrombosis Seemingly contradictory findings already exist with regard to the contribution of GPIbalpha and integrin alpha(2) polymorphisms, but these discrepancies will be resolved once there is better standardization of clinical studies There is already substantial evidence that GPIbalpha VNTR A or B alleles, the GPIbalpha-5C allele, and integrin alpha(2) allele 1 (T(807)) each contribute to increased risk for morbidity in thrombotic disease However, larger, prospective genetic and epidemiological studies are needed to clarify the role of each of these polymorphisms, the contribution of other platelet receptor polymorphisms, and the synergistic effects of combinations of these factors In addition, in vitro studies that establish the functional relevance of these polymorphisms will provide sound biological explanations for the results of clinical correlation studies

The Influence of Platelet Collagen Receptor Polymorphisms in Hemostasis and Thrombotic Disease

Background: Our study evaluated the expression of vascular endothelial growth factor (VEGF), CD31 and D2-40 in involved and uninvolved skin of 18 patients with rosacea.



Methods:  Immunostaining of facial skin specimens with VEGF, CD31 and D2-40 was compared between the lesional and the non-lesional skin of patients with erythemotelangiectatic and papulopustular rosacea.



Results:  Significantly increased dermal expression of VEGF in lesional vs. non-lesional skin (88.9% and 55.6%) was observed. Dermal expression of CD31 and D2-40 was also increased in lesional vs. non-lesional skin. There was no statistically significant difference in cutaneous expression of VEGF, CD31 and D2-40 between patients with papulopustular and erythemotelangiectatic rosacea, and no correlation was found between disease duration and immunoreactivity of VEGF, CD31or D2-40.



Conclusions:  Our study showed marked immunostaining of lesional skin with VEGF, CD31 and D2-40 compared with non-lesional skin. Increased immunoreactivity of D2-40 in lesional skin is interesting, given that none of the patients had facial edema. There are no published data regarding the role of lymphangiogenesis in patients with non-phymatous rosacea; thus, our study represents a new understanding of its pathogenesis. Lack of correlation between D2-40 expression and disease duration suggests that lymphatics are involved early in the pathogenesis of rosacea and do not constitute a late event.

Lymphangiogenesis and angiogenesis in non-phymatous rosacea.

BY DR. PAUL DIMUZIO The vascular system involves the heart and blood vessels. The blood vessels include arteries, which are tubes that transport blood from your heart to the rest of your body, and veins, which return the blood to your heart. This complex system is involved in many diverse functions, but the most important is transporting vital oxygen and nutrients to your tissues and organs. ARTERIES are thicker and are prone to developing blockages or dilations. VEINS are thinner and have valves that keep the blood moving back toward the heart. The larger deep veins of the legs can develop clots. Blood vessels are composed of three layers.

靖史佐藤

Papers

Vascular Biology の最近の進歩

靖史 佐藤

Papers

Vascular Biology の最近の進歩

靖史佐藤