Lung hyperinflation is known to be an important contributing factor in the pathogenesis of ventilator-induced lung injury. Mechanical stretch causes epithelial barrier dysfunction and an increase in alveolar permeability, although the precise mechanisms have not been completely elucidated. p120-catenin is an adherens junction-associated protein that regulates cell-cell adhesion. In this study, ...

Substantial evidence has indicated that osteoblastic differentiation may be regulated by mechanical loads or bone morphogenetic protein-2 (BMP-2). BMP-2-induced in vivo osteogenesis can be significantly enhanced in the presence of mechanical stimuli, revealing the therapeutic potential of the combined application of BMP-2 and mechanical loads in clinical bone diseases (e.g., bone fractures and ...

Microarrays were utilized to determine gene expression of vascular endothelial cells (ECs) subjected to mechanical stretch for insight into the role of strain in vascular pathophysiology. Over 4,000 genes were screened for expression changes resulting from cyclic strain (10%, 1 Hz) of human umbilical vein ECs for 6 and 24 h. Comparison of t-statistics and adjusted P values identified genes havi...

Standley, Paul R., Tamar J. Obards, and Cherie L. Martina. Cyclic stretch regulates autocrine IGF-I in vascular smooth muscle cells: implications in vascular hyperplasia. Am. J. Physiol. 276 (Endocrinol. Metab. 39): E697–E705, 1999.—Vascular smooth muscle cells (VSMC) subjected to acute or chronic stretch display enhanced growth rates in vitro and in vivo. Clinical examples of vascular hyperpla...

PURPOSE We investigated succinate metabolism in cells undergoing clinically relevant cyclic stretch and in spontaneously hypertensive rat (SHR) retina. METHODS We seeded ARPE-19 cells on 6-well BioFlex collagen I-coated, silicone elastomer-bottomed culture plates. Cells then were subjected to pulsatile stretch using a computer-controlled vacuum stretch apparatus. A physiologic stretch frequen...

This study was designed to determine whether cyclic stretch induces a persistent pulmonary hypertension of the newborn (PPHN) phenotype of increased NADPH oxidase (Nox) 4 signaling in control pulmonary artery smooth muscle cells (PASMC), and to identify the signal transduction molecules involved. To achieve this, PPHN was induced in lambs by antenatal ligation of the ductus arteriosus at 128 da...

Abnormal proliferation of endothelial cells (ECs) is important in vascular remodeling during hypertension, but the mechanisms are still unclear. In hypertensive rats caused by abdominal aortic coarctation, the expression of G-protein-coupled receptor kinase 6 (GRK6) in ECs at common carotid artery was repressed in vivo, and EC proliferation was increased. 15% cyclic stretch in vitro, which mimi...

The reasons for bacterial proliferation in the lungs of mechanically ventilated patients are poorly understood. We hypothesized that prolonged cyclic stretch of lung cells influenced bacterial growth. Human alveolar type II-like A549 cells were submitted in vitro to prolonged cyclic stretch. Bacteria were cultured in conditioned supernatants from cells submitted to stretch and from control stat...

Microtubules are structural components of the cytoskeleton that determine cell shape, polarity, and motility in cooperation with the actin filaments. In order to determine the role of microtubules in cell alignment, human airway smooth muscle cells were exposed to cyclic uniaxial stretch. Human airway smooth muscle cells, cultured on type I collagen-coated elastic silicone membranes, were stret...

Enzyme activity plays an essential role in many physiological processes and diseases such as pulmonary emphysema. While the lung is constantly exposed to cyclic stretching, the effects of stretch on the mechanical properties of the extracellular matrix (ECM) during digestion have not been determined. We measured the mechanical and failure properties of elastin-rich ECM sheets loaded with static...