Editors' ChoiceBioengineering

Going With the Flow

See allHide authors and affiliations

Science Translational Medicine  02 Feb 2011:
Vol. 3, Issue 68, pp. 68ec15
DOI: 10.1126/scitranslmed.3002179

Myriad self-help books encourage readers to open their hearts in order to live fuller lives. How right they are. Coronary artery disease—a condition that arises from the closing off of blood vessels that feed the heart—is the leading cause of various health problems and death in the developed world. These vessel blockages cause restricted blood flow (a condition referred to as ischemia), reducing the supply of oxygen and nutrients to cardiac tissue and leading to pain and increased risk of heart attack and heart failure. Therapeutic angiogenesis is one promising minimally invasive treatment that involves the delivery of growth factors [such as basic fibroblast growth factor (βFGF)] to affected heart tissue to stimulate blood vessel formation at the point of the injury. However, to be effective these growth factors must be retained at the ischemic site so as to reduce systemic side effects and also to allow for adequate time for new blood vessel formation.

To address this delivery issue, Garbern et al. created a temperature- and pH-sensitive hydrogel as an injectable growth factor delivery system. This hydrogel is liquid at room temperature and solidifies at body temperature. In addition, the new material degrades as the pH at the injection location rises from 6.8, the pH of heart tissue with poor blood flow, to 7.4, the pH of tissue with normal blood flow. When injected into blood-starved heart tissue in a rat model, the FGF-loaded hydrogel stimulated blood vessel formation and improved regional blood flow. These results highlight the potential of sustained and targeted growth factor delivery to stimulate blood vessel formation as a treatment for coronary artery disease.

J. Garbern et al., Delivery of basic fibroblast growth factor with a pH-responsive, injectable hydrogel to improve angiogenesis in infarcted myocardium. Biomaterials 32, 2407–2416 (2011). [Abstract]

Navigate This Article