The O’Rourke Lab uses an integrated approach to study the biophysics and physiology of cardiac cells in normal and diseased states. Research in our lab has incorporated mitochondrial energetics, Ca2+ dynamics, and electrophysiology to provide tools for studying how defective function of one component of the cell can lead to catastrophic effects on whole cell and whole organ function. By understanding the links between Ca2+, electrical excitability and energy production, we hope to understand the cellular basis of cardiac arrhythmias, ischemia-reperfusion injury, and sudden death. We use state-of-the-art techniques, including single-channel and whole-cell patch clamp, microfluorimetry, conventional and two-photon fluorescence imaging, and molecular biology to study the structure and function of single proteins to the intact muscle. Experimental results are compared with simulations of computational models in order to understand the findings in the context of the system as a whole. Ongoing studies in our lab are focused on identifying the specific molecular targets modified by oxidative or ischemic stress and how they affect mitochondrial and whole heart function. The motivation for all of the work is to understand • how the molecular details of the heart cell work together to maintain function and • how the synchronization of the parts can go wrong Rational strategies can then be devised to correct dysfunction during the progression of disease through a comprehensive understanding of basic mechanisms. Brian O’Rourke, PhD, is a professor in the Division of Cardiology and Vice Chair of Basic and Translational Research, Department of Medicine, at the Johns Hopkins University.

The Systems Biology Lab applies methods of multiscale modeling to problems of cancer and cardiovascular disease, and examines the systems biology of angiogenesis, breast cancer and peripheral artery disease (PAD). Using coordinated computational and experimental approaches, the lab studies the mechanisms of breast cancer tumor growth and metastasis to find ways to inhibit those processes. We use bioinformatics to discover novel agents that affect angiogenesis and perform in vitro and in vivo experiments to test these predictions. In addition we study protein networks that determine processes of angiogenesis, arteriogenesis and inflammation in PAD. The lab also investigates drug repurposing for potential applications as stimulators of therapeutic angiogenesis, examines signal transduction pathways and builds 3D models of angiogenesis. The lab has discovered over a hundred novel anti-angiogenic peptides, and has undertaken in vitro and in vivo studies testing their activity under different conditions. We have investigated structure-activity relationship (SAR) doing point mutations and amino acid substitutions and constructed biomimetic peptides derived from their endogenous progenitors. They have demonstrated the efficacy of selected peptides in mouse models of breast, lung and brain cancers, and in age-related macular degeneration.

The Richard Rivers Lab researches vascular communication with a focus on microcirculation physiology. Our team seeks to determine how metabolic demands are passed between tissue and the vascular network as well as along the vascular network itself. Our goal is to better understand processes of diseases such as cancer and diabetes, which could lead to the development of more targeted drugs and treatment. We are also working to determine the role for inwardly rectifying potassium channels (Kir) 2.1 and 6.1 in signaling along the vessel wall as well as the role of gap junctions.