Many studies during the past two decades have shed light on a wide range of cellular responses to mechanical stimulation. It is now widely accepted that stresses experienced in vivo are instrumental in numerous pathologies. One of the first diseases found to be linked to cellular stress was atherosclerosis, where it was demonstrated that hemodynamic shear stress influences endothelial function, and that conditions of low or oscillatory shear stress are conducive to the formation and growth of atherosclerotic lesions. Even before then, the role of mechanical stress on bone growth and healing was widely recognized, and since then, many other stress-influenced cell functions have been identified.
Many have investigated the signaling cascades that become activated as a consequence of mechanical stress, and these are generally well characterized. The initiating process, however, by which cells convert the applied force into a biochemical signal, termed “mechanotransduction,” is much more poorly understood, and only recently have researchers begun to unravel some of these fundamental mechanisms. Various processes and theories have been proposed to explain this phenomenon. The objective of this book is to bring together these different viewpoints to cellular mechanotransduction, ranging from the molecular basis of mechanotransduction phenomena to the tissue-specific events that lead to such processes. Our intent is to present in a single text the many and varied ways in which cellular mechanotransduction is viewed and, in doing so, spur on new experiments to test the theories, or the development of new theories themselves. We view this as an ongoing debate, where one of the leading proponents of each viewpoint could present his or her most compelling arguments in support of the model, so that members of the larger scientific community could form their own opinions. As such, this was intended to be a monograph that captured the current state of a rapidly evolving field. Since we began this project, however, it has been suggested that this book might meet the growing need for a text for courses taught specifically on cellular mechanotransduction. More broadly, it could be used to introduce concepts at the intersection of mechanics and biology, a field of study that has come to be termed “mechanobiology.” Or, even more broadly, this collection might be useful as supplemental readings for a course that covers a range of topics in molecular, cellular, and tissue biomechanics.