Role of matrix Gla protein in angiotensin II-induced exacerbation of vascular calcification

Guanghong Jia, Ryan M Stormont, Deepak M Gangahar, Devendra K Agrawal
American Journal of Physiology. Heart and Circulatory Physiology 2012 September 1, 303 (5): H523-32
Vascular calcification predicts an increased risk for cardiovascular events in atherosclerosis, diabetes, and end-stage kidney diseases. Matrix Gla protein (MGP), an inhibitor of calcification, limits calcium phosphate deposition in the vessel wall. There are many factors contributing to the progression of atherosclerosis, including hypertension, hyperlipidemia, the renin-angiotensin system, and inflammation. Angiotensin II (ANG II) plays a crucial role in the atherogenic process through not only its pressor responses but also its growth-promoting and inflammatory effects. In this study, we investigated the role of MGP in ANG II-induced exacerbation of vascular calcification in human vascular smooth muscle cells (VSMCs). The expression of MGP, calcification, and apoptosis in human VSMCs were examined by Western blot analysis, real-time PCR, in situ terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling, and enzyme-linked immunosorbent assay, respectively. Increase in VSMC calcification in human atherosclerotic plaques upregulates MGP expression and apoptosis in a negative feedback manner. ANG II inhibited MGP expression in VSMCs via and in vitro in a dose- and time-dependent manner through ANG II type 1 receptor and NF-κB signaling pathway. Meanwhile, MGP inhibited the calcification, caspase-3 activity, activation of runt-related transcription factor 2, and release of inflammatory cytokines by VSMCs induced by calcification medium (2.5 mM P(i)) and ANG II in vitro. These observations provide evidence that ANG II exacerbates vascular calcification through activation of the transcription factors, runt-related transcription factor 2 and NF-κB, and regulation of MGP, inflammatory cytokines expression in human VSMCs.

Full Text Links

Find Full Text Links for this Article


You are not logged in. Sign Up or Log In to join the discussion.

Related Papers

Remove bar
Read by QxMD icon Read

Save your favorite articles in one place with a free QxMD account.


Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"