Pedro Bullón1, Beatriz Castejón-Vega2, Lourdes Román-Malo1, María Paz Jimenez-Guerrero3, David Cotán3, Tamara Y Forbes-Hernandez4, Alfonso Varela-López5, Antonio J Pérez-Pulido6, Francesca Giampieri4, José L Quiles5, Maurizio Battino4, José A Sánchez-Alcázar3, Mario D Cordero7. 1. Research Laboratory, Dental School, University of Sevilla, Seville, Spain; Department of Periodontology, Dental School, University of Sevilla, Seville, Spain. 2. Research Laboratory, Dental School, University of Sevilla, Seville, Spain. 3. Centro Andaluz de Biología del Desarrollo (CABD), and Centro de Investigación Biomédica en Red: Enfermedades Raras, Instituto de Salud Carlos III, Consejo Superior de Investigaciones Científicas, Universidad Pablo de Olavide, Seville, Spain. 4. Dipartimento di Scienze Cliniche Specialistiche ed Odontostomatologiche, Sez. Biochimica, Università Politecnica delle Marche, Ancona, Italy. 5. Department of Physiology, Institute of Nutrition and Food Technology "José Mataix", Biomedical Research Center (CIBM), University of Granada, Armilla, Spain. 6. Centro Andaluz de Biología del Desarrollo (CABD), Universidad Pablo de Olavide-CSIC-Junta de Andalucía, Seville, Spain. 7. Department of Physiology, Institute of Nutrition and Food Technology "José Mataix", Biomedical Research Center (CIBM), University of Granada, Armilla, Spain. Electronic address: mdcormor@ugr.es.
Abstract
BACKGROUND: Cathepsin C (CatC) is a lysosomal enzyme involved in activation of serine proteases from immune and inflammatory cells. Several loss-of-function mutations in the CatC gene have been shown to be the genetic mark of Papillon-Lefèvre syndrome (PLS), a rare autosomal recessive disease characterized by severe early-onset periodontitis, palmoplantar hyperkeratosis, and increased susceptibility to infections. Deficiencies or dysfunction in other cathepsin family proteins, such as cathepsin B or D, have been associated with autophagic and lysosomal disorders. OBJECTIVES: Here we characterized the basis for autophagic dysfunction in patients with PLS by analyzing skin fibroblasts derived from patients with several mutations in the CatC gene and reduced enzymatic activity. METHODS: Skin fibroblasts were isolated from patients with PLS assessed by using genetic analysis. Authophagic flux dysfunction was evaluated by examining accumulation of p62/SQSTM1 and a bafilomycin assay. Ultrastructural analysis further confirmed abnormal accumulation of autophagic vesicles in mutant cells. A recombinant CatC protein was produced by a baculovirus system in insect cell cultures. RESULTS: Mutant fibroblasts from patients with PLS showed alterations in oxidative/antioxidative status, reduced oxygen consumption, and a marked autophagic dysfunction associated with autophagosome accumulation. These alterations were accompanied by lysosomal permeabilization, cathepsin B release, and NLR family pyrin domain containing 3 (NLRP3) inflammasome activation. Treatment of mutant fibroblasts with recombinant CatC improved cell growth and autophagic flux and partially restored lysosomal permeabilization. CONCLUSIONS: Our data provide a novel molecular mechanism underlying PLS. Impaired autophagy caused by insufficient lysosomal function might represent a new therapeutic target for PLS.
BACKGROUND:Cathepsin C (CatC) is a lysosomal enzyme involved in activation of serine proteases from immune and inflammatory cells. Several loss-of-function mutations in the CatC gene have been shown to be the genetic mark of Papillon-Lefèvre syndrome (PLS), a rare autosomal recessive disease characterized by severe early-onset periodontitis, palmoplantar hyperkeratosis, and increased susceptibility to infections. Deficiencies or dysfunction in other cathepsin family proteins, such as cathepsin B or D, have been associated with autophagic and lysosomal disorders. OBJECTIVES: Here we characterized the basis for autophagic dysfunction in patients with PLS by analyzing skin fibroblasts derived from patients with several mutations in the CatC gene and reduced enzymatic activity. METHODS: Skin fibroblasts were isolated from patients with PLS assessed by using genetic analysis. Authophagic flux dysfunction was evaluated by examining accumulation of p62/SQSTM1 and a bafilomycin assay. Ultrastructural analysis further confirmed abnormal accumulation of autophagic vesicles in mutant cells. A recombinant CatC protein was produced by a baculovirus system in insect cell cultures. RESULTS: Mutant fibroblasts from patients with PLS showed alterations in oxidative/antioxidative status, reduced oxygen consumption, and a marked autophagic dysfunction associated with autophagosome accumulation. These alterations were accompanied by lysosomal permeabilization, cathepsin B release, and NLR family pyrin domain containing 3 (NLRP3) inflammasome activation. Treatment of mutant fibroblasts with recombinant CatC improved cell growth and autophagic flux and partially restored lysosomal permeabilization. CONCLUSIONS: Our data provide a novel molecular mechanism underlying PLS. Impaired autophagy caused by insufficient lysosomal function might represent a new therapeutic target for PLS.
Authors: Beatriz Castejón-Vega; Maurizio Battino; José L Quiles; Beatriz Bullon; Mario D Cordero; Pedro Bullón Journal: Antioxidants (Basel) Date: 2021-01-12
Authors: Beatriz Castejón-Vega; Alejandro Rubio; Antonio J Pérez-Pulido; José L Quiles; Jon D Lane; Beatriz Fernández-Domínguez; María Begoña Cachón-González; Carmen Martín-Ruiz; Alberto Sanz; Timothy M Cox; Elísabet Alcocer-Gómez; Mario D Cordero Journal: Cells Date: 2021-11-11 Impact factor: 6.600