RESUMO
RATIONALE: Pathogenic (P)/likely pathogenic (LP) SMAD3 variants cause Loeys-Dietz syndrome type 3 (LDS3), which is characterized by arterial aneurysms, dissections and tortuosity throughout the vascular system combined with osteoarthritis. OBJECTIVES: Investigate the impact of P/LP SMAD3 variants with functional tests on patient-derived fibroblasts and vascular smooth muscle cells (VSMCs), to optimize interpretation of SMAD3 variants. METHODS: A retrospective analysis on clinical data from individuals with a P/LP SMAD3 variant and functional analyses on SMAD3 patient-derived VSMCs and SMAD3 patient-derived fibroblasts, differentiated into myofibroblasts. RESULTS: Individuals with dominant negative (DN) SMAD3 variant in the MH2 domain exhibited more major events (66.7% vs. 44.0%, P = 0.054), occurring at a younger age compared to those with haploinsufficient (HI) variants. The age at first major event was 35.0 years [IQR 29.0-47.0] in individuals with DN variants in MH2, compared to 46.0 years [IQR 40.0-54.0] in those with HI variants (P = 0.065). Fibroblasts carrying DN SMAD3 variants displayed reduced differentiation potential, contrasting with increased differentiation potential in HI SMAD3 variant fibroblasts. HI SMAD3 variant VSMCs showed elevated SMA expression and altered expression of alternative MYH11 isoforms. DN SMAD3 variant myofibroblasts demonstrated reduced extracellular matrix formation compared to control cell lines. CONCLUSION: Distinguishing between P/LP HI and DN SMAD3 variants can be achieved by assessing differentiation potential, and SMA and MYH11 expression. The differences between DN and HI SMAD3 variant fibroblasts and VSMCs potentially contribute to the differences in disease manifestation. Notably, myofibroblast differentiation seems a suitable alternative in vitro test system compared to VSMCs.
Assuntos
Fibroblastos , Estudos de Associação Genética , Síndrome de Loeys-Dietz , Músculo Liso Vascular , Proteína Smad3 , Humanos , Proteína Smad3/genética , Proteína Smad3/metabolismo , Síndrome de Loeys-Dietz/genética , Síndrome de Loeys-Dietz/patologia , Masculino , Feminino , Fibroblastos/metabolismo , Adulto , Pessoa de Meia-Idade , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Diferenciação Celular/genética , Linhagem Celular , Miócitos de Músculo Liso/metabolismo , Estudos Retrospectivos , Fenótipo , Miofibroblastos/metabolismo , Miofibroblastos/patologia , MutaçãoAssuntos
Síndrome de Loeys-Dietz , Mutação de Sentido Incorreto , Receptor do Fator de Crescimento Transformador beta Tipo I , Humanos , Receptor do Fator de Crescimento Transformador beta Tipo I/genética , Síndrome de Loeys-Dietz/genética , Síndrome de Loeys-Dietz/patologia , Síndrome de Loeys-Dietz/complicações , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Feminino , MasculinoRESUMO
Yang et al.1 generate tissue engineered blood vessels from hiPSC-derived smooth muscle cells harboring a mutation found in Loeys-Dietz syndrome. In vitro and in vivo data from these vessels provide new insight into the molecular physiology of aortic aneurysms and may create a paradigm for understanding a suite of vascular diseases.
Assuntos
Aneurisma Aórtico , Prótese Vascular , Engenharia Tecidual , Humanos , Aneurisma Aórtico/patologia , Aneurisma Aórtico/fisiopatologia , Animais , Células-Tronco Pluripotentes Induzidas/metabolismo , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia , Síndrome de Loeys-Dietz/genética , Síndrome de Loeys-Dietz/patologiaRESUMO
Thoracic aortic aneurysm (TAA) is a life-threatening vascular disease frequently associated with underlying genetic causes. An inadequate understanding of human TAA pathogenesis highlights the need for better disease models. Here, we established a functional human TAA model in an animal host by combining human induced pluripotent stem cells (hiPSCs), bioengineered vascular grafts (BVGs), and gene editing. We generated BVGs from isogenic control hiPSC-derived vascular smooth muscle cells (SMCs) and mutant SMCs gene-edited to carry a Loeys-Dietz syndrome (LDS)-associated pathogenic variant (TGFBR1A230T). We also generated hiPSC-derived BVGs using cells from a patient with LDS (PatientA230T/+) and using genetically corrected cells (Patient+/+). Control and experimental BVGs were then implanted into the common carotid arteries of nude rats. The TGFBR1A230T variant led to impaired mechanical properties of BVGs, resulting in lower burst pressure and suture retention strength. BVGs carrying the variant dilated over time in vivo, resembling human TAA formation. Spatial transcriptomics profiling revealed defective expression of extracellular matrix (ECM) formation genes in PatientA230T/+ BVGs compared with Patient+/+ BVGs. Histological analysis and protein assays validated quantitative and qualitative ECM defects in PatientA230T/+ BVGs and patient tissue, including decreased collagen hydroxylation. SMC organization was also impaired in PatientA230T/+ BVGs as confirmed by vascular contraction testing. Silencing of collagen-modifying enzymes with small interfering RNAs reduced collagen proline hydroxylation in SMC-derived tissue constructs. These studies demonstrated the utility of BVGs to model human TAA formation in an animal host and highlighted the role of reduced collagen modifying enzyme activity in human TAA formation.
Assuntos
Prótese Vascular , Colágeno , Células-Tronco Pluripotentes Induzidas , Receptor do Fator de Crescimento Transformador beta Tipo I , Animais , Humanos , Receptor do Fator de Crescimento Transformador beta Tipo I/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I/genética , Células-Tronco Pluripotentes Induzidas/metabolismo , Colágeno/metabolismo , Aneurisma da Aorta Torácica/genética , Aneurisma da Aorta Torácica/patologia , Aneurisma da Aorta Torácica/metabolismo , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia , Ratos Nus , Modelos Animais de Doenças , Ratos , Bioengenharia , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Edição de Genes , Síndrome de Loeys-Dietz/genética , Síndrome de Loeys-Dietz/patologia , MasculinoRESUMO
No disponible