system
Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: BACKGROUND, METHODS, RESULTS. Meshes: Angioplasty, Balloon, Angiotensin II, Animals, Apoptosis, Bone Morphogenetic Protein 2, Bone Morphogenetic Protein 4, Bone Morphogenetic Protein 7, Bone Morphogenetic Proteins, Carotid Artery Injuries, Caspase 3, Cell Proliferation, Cells, Cultured, Chromatin Assembly and Disassembly, Disease Models, Animal, Male, Muscle, Smooth, Vascular, Myocytes, Smooth Muscle, Platelet-Derived Growth Factor, Proteins, RNA Interference, RNA, Messenger, RNA, Small Interfering, Rabbits, Rats, Rats, Sprague-Dawley, Time Factors, Transforming Growth Factor beta1.
user
Does the bone morphogenetic protein antagonist gremlin promote vascular smooth muscle cell apoptosis? Context: Previous studies from our laboratory demonstrated that gremlin significantly increases vascular smooth muscle cell (VSMC) proliferation and migration. The present study investigates gremlin expression in the initial stages of rat carotid balloon injury and its effects on VSMC apoptosis. Gremlin mRNA expression was evaluated in rat carotids and cultured VSMCs by quantitative PCR. Apoptosis was analyzed in A7r5 cells and rabbit primary VSMCs following gremlin gene overexpression or silencing by chromatin morphology and caspase-3 activity. Vascular injury promoted a significant decrease in gremlin mRNA levels. In addition, platelet-derived growth factor, angiotensin II and transforming growth factor (TGF)-beta1 promoted coordinated regulation of gremlin and bone morphogenetic protein (BMP)-4 expression in opposite directions according to the confluence status of VSMC culture. In A7r5 cells, gremlin overexpression was able to increase apoptosis, as demonstrated by chromatin morphology and caspase-3 activity, while BMP administration promoted opposite effects. Finally, in agreement with our results, gremlin gene silencing effectively suppressed apoptosis in A7r5 cells and rabbit VSMCs.
assistant
Gremlin is regulated by growth factors and vascular injury and is involved in modulation of VSMC apoptosis. Modifications of gremlin expression during vascular injury may contribute to the apoptosis resistance of VSMCs. Final Decision: yes