Mesenchymal stem cells and smooth muscle cells in abdominal aortic aneurysm repair induced in rats by increase of MMP-2 and MMP-9 expression

• Grant number: 12/17067-8
• Support type: Scholarships in Brazil - Post-Doctorate
• Effective date (Start): December 01, 2012
• Effective date (End): November 30, 2014
• Field of knowledge: Health Sciences - Medicine - Pathological Anatomy and Clinical Pathology
• Principal researcher: Simone Gusmão Ramos
• Grantee: Cristiane Tefé da Silva
• Home Institution: Faculdade de Medicina de Ribeirão Preto (FMRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

Mesenchymal stem cells and smooth muscle cells in abdominal aortic aneurysm repair induced in rats by increase of MMP-2 and MMP-9 expressionAbdominal aortic aneurysm (AAA) is defined as a dilatation of the abdominal aorta that exceeds 50% of the normal diameter. The AAAs were considered biomechanical problems resulting in irreversible structural lesions, with weakening and progressive dilation of the aortic wall. However, evidence has confirmed that the AAAs are the result of a chronic degenerative process, especially the destruction of the medial layer, with degradation of extracellular matrix and neovascularization. Experimental models of AAAs have been described in the literature; however, these models have several limitations. An ideal model of AAA induction would include pathological features similar to those seen in humans. It was developed in our laboratory a new model of induced AAA in rats by combining two phenomena: vascular injury and hemodynamic changes in blood flow. Surgical repair is currently the only effective method of AAA treatment. But this intervention is costly associated with high mortality rates. The stem cell therapy has an important role in the development of new tissue and may be applied across a broad range of human diseases. The mesenchymal stem cells (MSCs) are capable of differentiating into connective tissue, smooth muscle cells (SMCs) and cells of the vascular system. The SMCs has an important role in AAAs, with consequent depletion of the media layer during the aneurysms formation. However, little is known about the stem cell therapy in AAA. The objective of this study is to investigate the effects of therapy with MSCs and SMCs in already-formed aneurysm. This project represents an innovative proposal relative to stem cells therapy in aortic aneurysms repair and may provide new subsidies for knowledge in this important area.