Role of the pulmonary surfactant protein SP-C in alveolar homeostasis

Pulmonary surfactant, a lipoprotein complex that covers the alveoli, prevents lung collapse by reducing surface tension at the air-liquid interface. It is composed of lipids (90% by mass), including dipalmitoylphosphatidylcholine (DPPC, 40%), unsaturated phospholipids (35%) and neutral lipids such a...

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Detalles Bibliográficos
Autor: Morán Lalangui, Juranny Michelle
Tipo de recurso: tesis doctoral
Fecha de publicación:2026
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/132038
Acceso en línea:https://hdl.handle.net/20.500.14352/132038
Access Level:acceso abierto
Palabra clave:661.185(043.2)
Alveolar homeostasis
Pulmonary surfactant
Protein SP-C
Homeostasis alveolar
Surfactante pulmonar
Proteína SP-C
Fisiología
2411.17 Fisiología de la Respiración
Descripción
Sumario:Pulmonary surfactant, a lipoprotein complex that covers the alveoli, prevents lung collapse by reducing surface tension at the air-liquid interface. It is composed of lipids (90% by mass), including dipalmitoylphosphatidylcholine (DPPC, 40%), unsaturated phospholipids (35%) and neutral lipids such as cholesterol (8-10%). Additionally, it contains specific proteins (8-10%) essential for its function. Pulmonary surfactant proteins A and D (SP-A and SP-D) are hydrophilic proteins belonging to the collectin family and are involved in the innate defense of the lung, while pulmonary surfactant proteins B and C (SP-B and SP-C) are very small, highly cationic, and extraordinarily hydrophobic proteins responsible for the biophysical function of surfactant, as they participate in the rearrangement of surfactant membranes required during breathing cycles. Pulmonary surfactant acts as a barrier against microorganisms and harmful particles inhaled into the lungs, through a cross-talk with alveolar macrophages (AMϕ). In the alveolar spaces, surfactant is challenged by an oxidative environment that can affect its function. Therefore, in healthy lungs, a balance is maintained between its secretion by type II alveolar epithelial cells (AECII) and its recycling and clearance. Alveolar homeostasis depends on the interaction between AECII, AMϕ, and surfactant, ensuring pulmonary protection and performance...