Naslov
The expression of alpha-smooth muscle actin and osteopontin in vascular calcification

Autori
Ćelić, Tanja ; Marić, Ivana ; Markić, Dean ; Španjol, Josip ; Gršković, Antun ; Bobinac, Dragica

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Bone / - : Elsevier, 2010, 223-223

Skup
37th European Symposium on Calcified Tissues

Mjesto i datum
Glasgow, Ujedinjeno Kraljevstvo, 26.06.2010. - 30.06.2010

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
vascular calcification; osteopontin; smooth muscle actin

Sažetak
Vascular calcification is a process characterized with mineralization of soft tissues, triggered by disorders in calcium-phosphate homeostasis or activation of inflammatory< cytokines. Hyperphosphatemia has the potential to change the phenotype of human vascular smooth muscle cells (VSMCs) from contractile to secretory phenotype. Calcifying VMSCs undergo osteoblastic differentiation and express markers and transcription factors specific for osteoblasts. Core binding factor alpha-1 (Cbfa-1) is an essential transcription factor for osteoblastic differentiation and osteogenesis, and is expressed in VSCMs. The activity of Cbfa-1 affects its downstream protein osteopontin (OPN), enhancing its expression in calcified areas.. Alpha-smooth muscle actin (alpha-SMA)is a marker of VSMC phenotype.Change of VSMC phenotype is underlying process of atherosclerosis and medial calcification pathogenesis. Since transformed VSMC lose contractile capabilities, the number of alpha-SMA positive cells is decreased. In our study we analyzed samples of human renal arteries using immunohistochemistry to show expression and localization of alpha-SMA and osteopontin in vascular calcification. Tissue samples were divided according to histological examination into following groups: control arteries without signs of calcification, atherosclerotic arteries with intimal calcification and arteries with calcification localized in the media. We found decreased number of alpha-SM>>A positive cells in calcified lesions compared to control samples. At the same time OPN was upregulated and colocolazied with sites of calcification in tunica media and atherosclerosis. Higher expression of OPN was associated with severe cases of calcification. We noticed negative correlation between OPN and alpha-SMA expression. Calcification of soft tissues is actively regulated process. OPN as osteoblast specific marker indicates that vascular calcification is analogous to bone mineralization.

Izvorni jezik
Engleski

Znanstvena područja
Temeljne medicinske znanosti

POVEZANOST RADA