The protective effects of renin-angiotensin system componts on vascular calcification

Elastic Fibers and F-Box and WD-40 Domain-Containing Protein 2 in Bovine Periosteum and Blood Vessels

Elastic fibers form vessel walls, and elastic fiber calcification causes serious vascular diseases. Elastin is a well-known elastic fiber component; however, the insoluble nature of elastic fibers renders elastic fiber component analysis difficult. A previous study investigated F-box and WD-40 domain-containing protein 2 (FBXW2) in the cambium layer of bovine periosteum and hypothesized that fiber structures of FBXW2 are coated with osteocalcin during explant culture. Here, FBXW2 was expressed around some endothelial cells but not in all microvessels of the bovine periosteum. The author hypothesized that FBXW2 is expressed only in blood vessels with elastic fibers. Immunostaining and Elastica van Gieson staining indicated that FBXW2 was expressed in the same regions as elastic fibers and elastin in the cambium layer of the periosteum. Alpha-smooth muscle actin (αSMA) was expressed in microvessels and periosteum-derived cells. Immunostaining and observation of microvessels with serial sections revealed that osteocalcin was not expressed around blood vessels at 6 and 7 weeks. However, blood vessels and periosteum connoted elastic fibers, FBXW2, and αSMA. These findings are expected to clarify the processes involved in the calcification of elastic fibers in blood vessels.

Angiotensin-(1-7), a protective peptide against vascular aging

Vascular aging is a complex and multifaceted process that provokes profound molecular, structural, and functional changes in the vasculature. Eventually, these profound aging alterations make arteries more prone to vascular disease, including hypertension, atherosclerosis and other arterial complications that impact the organism beyond the cardiovascular system and accelerate frailty. For these reasons, preventing or delaying the hallmarks of vascular aging is nowadays a major health goal, especially in our aged societies. In this context, angiotensin(Ang)-(1-7), a major player of the protective branch of the renin-angiotensin system, has gained relevance over recent years as growing knowledge on its anti-aging properties is being unveiled. Here, we briefly review the main actions of Ang-(1-7) against vascular aging. These include protection against vascular cell senescence, anti-inflammatory and antioxidant effects together with the induction of cytoprotective systems. Ang-(1-7) further ameliorates endothelial dysfunction, a hallmark of vascular aging and disease, attenuates fibrosis and calcification and promotes protective angiogenesis and repair. Although further research is needed to better understand the anti-aging properties of Ang-(1-7) on the vasculature, this heptapeptide arises as a promising pharmacological tool for preventing vascular aging and frailty.

Vascular Calcification: New Insights Into BMP Type I Receptor A

Vascular calcification (VC) is a complex ectopic calcification process and an important indicator of increased risk for diabetes, atherosclerosis, chronic kidney disease, and other diseases. Therefore, clarifying the pathogenesis of VC is of great clinical significance. Numerous studies have shown that the onset and progression of VC are similar to bone formation. Members of the bone morphogenetic protein (BMP) family of proteins are considered key molecules in the progression of vascular calcification. BMP type I receptor A (BMPR1A) is a key receptor of BMP factors acting on the cell membrane, is widely expressed in various tissues and cells, and is an important “portal” for BMP to enter cells and exert their biological effect. In recent years, many discoveries have been made regarding the occurrence and treatment of ectopic ossification-related diseases involving BMP signaling targets. Studies have confirmed that BMPR1A is involved in osteogenic differentiation and that its high expression in vascular endothelial cells and smooth muscle cells can lead to vascular calcification. This article reviews the role of BMPR1A in vascular calcification and the possible underlying molecular mechanisms to provide clues for the clinical treatment of such diseases.