Richard A. Cohen, MD
MD, Johns Hopkins University
General field of research:
Affiliations other than medicine:
Evans Center for Interdisciplinary Biomedical Research
Vascular Biology Unit
Whitaker Cardiovascular Institute
Phone: (617)- 638 7115
Research group information
Vascular Biology Unit
Cardiovascular; Endothelium; Smooth muscle; Atherosclerosis
Summary of research interest:
The Vascular Biology Unit led by Dr. Richard Cohen seeks to understand why oxidants impair function of diseased arteries. His group has found that in diabetes, hypertension, and atherosclerosis, the vasodilator, nitric oxide is inactivated by superoxide, an oxidant produced in diseased blood vessels. As a result of this reaction an even more potent oxidant, peroxynitrite, is formed. At low levels, peroxynitrite S-glutathiolates proteins including the sarcoplasmic reticulum calcium ATPase and p21ras, modulating cell signaling. High levels of peroxynitrite can be blamed for inactivating these and other important proteins, such as manganese superoxide dismutase. As part of the BU Cardiovascular Proteomics Center, Dr. Cohen and his group are identifying chemical modifications of proteins formed by oxidants with mass spectrometric and protein tagging strategies. These modifications may serve as biomarkers for abnormal cell signaling and/or disease. Such markers have been found in diseased human arteries and platelets.
Ying J, Sharov V, Xu S, Jiang B, Gerrity R, Schöneich C, Cohen RA. 2008 Sep 15. Cysteine-674 oxidation and degradation of sarcoplasmic reticulum Ca(2+) ATPase indiabetic pig aorta. Free Radic Biol Med; 45(6):756-62.
Tong X, Ying J, Pimentel DR, Trucillo M, Adachi T, Cohen RA. 2008 Feb. High glucose oxidizes SERCA cysteine-674 and prevents inhibition by nitric oxide of smooth muscle cell migration. J Mol Cell Cardiol; 44(2):361-9.
Sethuraman M, Clavreul N, Huang H, McComb ME, Costello CE, Cohen RA. 2007 Mar 15. Quantification of oxidative posttranslational modifications of cysteine thiols of p21ras associated with redox modulation of activity using isotope-coded affinity tags and mass spectrometry. Free Radic Biol Med; 42(6):823-9.
Ying J, Tong X, Pimentel DR, Weisbrod RM, Trucillo MP, Adachi T, Cohen RA. 2007 Apr. Cysteine-674 of the sarco/endoplasmic reticulum calcium ATPase is required for the inhibition of cell migration by nitric oxide. Arterioscler Thromb Vasc Biol; 27(4):783-90.
Clavreul N, Bachschmid MM, Hou X, Shi C, Idrizovic A, Ido Y, Pimentel D, Cohen RA. 2006 Nov. S-glutathiolation of p21ras by peroxynitrite mediates endothelial insulin resistance caused by oxidized low-density lipoprotein. Arterioscler Thromb Vasc Biol; 26(11):2454-61.
Zang M, Xu S, Maitland-Toolan KA, Zuccollo A, Hou X, Jiang B, Wierzbicki M, Verbeuren TJ, Cohen RA. 2006 Aug. Polyphenols stimulate AMP-activated protein kinase, lower lipids, and inhibit accelerated atherosclerosis in diabetic LDL receptor-deficient mice. Diabetes; 55(8):2180-91.
Matsui R, Xu S, Maitland KA, Mastroianni R, Leopold JA, Handy DE, Loscalzo J, Cohen RA. 2006 Apr. Glucose-6-phosphate dehydrogenase deficiency decreases vascular superoxide and atherosclerotic lesions in apolipoprotein E(-/-) mice. Arterioscler Thromb Vasc Bio; 26(4):910-6.