La aterosclerosis es el principal problema médico en el síndrome de progeria de Hutchinson-Gilford (HGPS), una enfermedad causada por la expresión de la proteína mutante llamada progerina. Observamos en ratones progéricos la disfunción de células endoteliales y transición endotelial-mesenquimal (EndMT), un proceso inducido por la vía TGFβ1/SMAD3 activada por las células musculares lisas vasculares disfuncionales y que contribuye a la aterosclerosis. La inhibición de SMAD3 con SIS3 redujo la EndMT y mejoró el fenotipo vascular.
Resumen
Background: Atherosclerosis is the main medical problem in Hutchinson-Gilford progeria syndrome (HGPS), a rare premature aging disorder caused by the mutant lamin-A protein progerin. Recently, we found that limiting progerin expression to vascular smooth muscle cells (VSMCs) is sufficient to hasten atherosclerosis and death in Apoe-deficient mice. However, the impact of progerin-driven VSMC defects on endothelial cells (ECs) remained unclear.
Methods: Apoe- or Ldlr-deficient C57BL/6J mice with ubiquitous, VSMC-, EC- or myeloid-specific progerin expression fed normal or high-fat diet were used to study endothelial phenotype during HGPS-associated atherosclerosis. Endothelial permeability to low-density lipoproteins (LDL) was assessed by intravenous injection of fluorescently-labelled human LDL and confocal microscopy analysis of the aorta. Leukocyte recruitment to the aortic wall was evaluated by en face immunofluorescence. Endothelial-to-mesenchymal transition (EndMT) was assessed by qPCR and RNAseq in the aortic intima and by immunofluorescence in aortic root sections. Transforming growth factor β (TGFβ) signaling was analyzed by multiplex immunoassay in serum, by western blot in the aorta, and by immunofluorescence in aortic root sections. The therapeutic benefit of TGFβ1/SMAD3 pathway inhibition was evaluated in mice by intraperitoneal injection of the specific SMAD3 inhibitor SIS3, and vascular phenotype was assessed by Oil Red O staining, histology, and immunofluorescence in the aorta and the aortic root.
Results: Both ubiquitous and VSMC-specific progerin expression in Apoe-null mice provoked alterations in aortic ECs, including increased permeability to LDL and leukocyte recruitment. Atherosclerotic lesions in these progeroid mouse models, but not in EC- and myeloid-specific progeria models, contained abundant cells combining endothelial and mesenchymal features, indicating extensive EndMT triggered by dysfunctional VSMCs. Accordingly, the intima of ubiquitous and VSMC-specific progeroid models at the onset of atherosclerosis presented increased expression of EndMT-linked genes, especially those specific to fibroblasts and extracellular matrix. Aorta in both models showed activation of the TGFβ1/SMAD3 pathway, a major trigger of EndMT, and treatment of VSMC-specific progeroid mice with SIS3 alleviated the aortic phenotype.
Conclusions: Progerin-induced VSMC alterations promote EC dysfunction and EndMT via TGFβ1/SMAD3, identifying this process as a candidate target for HGPS treatment. These findings also provide insight into the complex role of EndMT during atherogenesis.
Methods: Apoe- or Ldlr-deficient C57BL/6J mice with ubiquitous, VSMC-, EC- or myeloid-specific progerin expression fed normal or high-fat diet were used to study endothelial phenotype during HGPS-associated atherosclerosis. Endothelial permeability to low-density lipoproteins (LDL) was assessed by intravenous injection of fluorescently-labelled human LDL and confocal microscopy analysis of the aorta. Leukocyte recruitment to the aortic wall was evaluated by en face immunofluorescence. Endothelial-to-mesenchymal transition (EndMT) was assessed by qPCR and RNAseq in the aortic intima and by immunofluorescence in aortic root sections. Transforming growth factor β (TGFβ) signaling was analyzed by multiplex immunoassay in serum, by western blot in the aorta, and by immunofluorescence in aortic root sections. The therapeutic benefit of TGFβ1/SMAD3 pathway inhibition was evaluated in mice by intraperitoneal injection of the specific SMAD3 inhibitor SIS3, and vascular phenotype was assessed by Oil Red O staining, histology, and immunofluorescence in the aorta and the aortic root.
Results: Both ubiquitous and VSMC-specific progerin expression in Apoe-null mice provoked alterations in aortic ECs, including increased permeability to LDL and leukocyte recruitment. Atherosclerotic lesions in these progeroid mouse models, but not in EC- and myeloid-specific progeria models, contained abundant cells combining endothelial and mesenchymal features, indicating extensive EndMT triggered by dysfunctional VSMCs. Accordingly, the intima of ubiquitous and VSMC-specific progeroid models at the onset of atherosclerosis presented increased expression of EndMT-linked genes, especially those specific to fibroblasts and extracellular matrix. Aorta in both models showed activation of the TGFβ1/SMAD3 pathway, a major trigger of EndMT, and treatment of VSMC-specific progeroid mice with SIS3 alleviated the aortic phenotype.
Conclusions: Progerin-induced VSMC alterations promote EC dysfunction and EndMT via TGFβ1/SMAD3, identifying this process as a candidate target for HGPS treatment. These findings also provide insight into the complex role of EndMT during atherogenesis.
noviembre 2024
Sobre el grupo investigador
Nuestro laboratorio investiga los mecanismos celulares y moleculares que conectan la expresión de lamina A/C y progerina con las enfermedades cardiovasculares (ECV) y el envejecimiento fisiológico y prematuro, utilizando modelos preclínicos en ratones y cerdos. Nos centramos en entender cómo estas proteínas nucleares contribuyen al desarrollo de ECV y en desarrollar nuevas terapias para el tratamiento del síndrome de progeria de Hutchinson-Gilford y sus complicaciones cardiovasculares.
Referencia del artículo
Hamczyk MR, Nevado RM, Gonzalo P, Andrés-Manzano MJ, Nogales P, Quesada V, Rosado A, Torroja C, Sánchez-Cabo F, Dopazo A, Bentzon JF, López-Otín C, Andrés V. 2024. Endothelial-to-Mesenchymal Transition Contributes to Accelerated Atherosclerosis in Hutchinson-Gilford Progeria Syndrome. Circulation. PMID: 39206565
https://doi.org/10.1161/CIRCULATIONAHA.123.065768
