{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,25]],"date-time":"2026-09-25T02:21:04Z","timestamp":1790302864518,"version":"4.1.0"},"reference-count":33,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2024,2,10]],"date-time":"2024-02-10T00:00:00Z","timestamp":1707523200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"\u201cInGene 2.0\u201d grant","award":["15397"],"award-info":[{"award-number":["15397"]}]},{"name":"\u201cInGene 2.0\u201d grant","award":["RC2023"],"award-info":[{"award-number":["RC2023"]}]},{"name":"Italian Ministry of Health","award":["15397"],"award-info":[{"award-number":["15397"]}]},{"name":"Italian Ministry of Health","award":["RC2023"],"award-info":[{"award-number":["RC2023"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Cells"],"abstract":"<jats:p>Objective: To identify novel biomarkers as an alternative diagnostic tool for limb girdle muscular dystrophy (LGMD). Background: LGMD encompasses a group of muscular dystrophies characterized by proximal muscles weakness, elevated CK levels and dystrophic findings on muscle biopsy. Heterozygous CAPN3 mutations are associated with autosomal dominant LGMD-4, while biallelic mutations can cause autosomal recessive LGMD-1. Diagnosis is currently often based on invasive methods requiring muscle biopsy or blood tests. In most cases Western blotting (WB) analysis from muscle biopsy is essential for a diagnosis, as muscle samples are currently the only known tissues to express the full-length CAPN3 isoform. Methods: We analyzed CAPN3 in a cohort including 60 LGMD patients. Selected patients underwent a complete neurological examination, electromyography, muscle biopsy, and skin biopsies for primary fibroblasts isolation. The amount of CAPN3 was evaluated by WB analysis in muscle and skin tissues. The total RNA isolated from muscle, fibroblast and urine was processed, and cDNA was used for qualitative analysis. The expression of CAPN3 was investigated by qRT-PCR. The CAPN3 3D structure has been visualized and analyzed using PyMOL. Results: Among our patients, seven different CAPN3 mutations were detected, of which two were novel. After sequencing CAPN3 transcripts from fibroblast and urine, we detected different CAPN3 isoforms surprisingly including the full-length transcript. We found comparable protein levels from fibroblasts and muscle tissue; in particular, patients harboring a novel CAPN3 mutation showed a 30% reduction in protein compared to controls from both tissues. Conclusions: Our findings showed for the first time the presence of the CAPN3 full-length transcript in urine and skin samples. Moreover, we demonstrated surprisingly comparable CAPN3 protein levels between muscle and skin samples, thus allowing us to hypothesize the use of skin biopsy and probably of urine samples as an alternative less invasive method to assess the amount of CAPN3 when molecular diagnosis turns out to be inconclusive.<\/jats:p>","DOI":"10.3390\/cells13040329","type":"journal-article","created":{"date-parts":[[2024,2,12]],"date-time":"2024-02-12T04:47:45Z","timestamp":1707713265000},"page":"329","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Novel Biomarkers for Limb Girdle Muscular Dystrophy (LGMD)"],"prefix":"10.3390","volume":"13","author":[{"given":"Sara","family":"Aguti","sequence":"first","affiliation":[{"name":"Department of Medicine, Surgery and Neurosciences, University of Siena, 53100 Siena, Italy"},{"name":"UOC Neurologia e Malattie Neurometaboliche, Azienda Ospedaliero-Universitaria Senese, Policlinico Le Scotte, Viale Bracci, 16, 53100 Siena, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gian Nicola","family":"Gallus","sequence":"additional","affiliation":[{"name":"Department of Medicine, Surgery and Neurosciences, University of Siena, 53100 Siena, Italy"},{"name":"UOC Neurologia e Malattie Neurometaboliche, Azienda Ospedaliero-Universitaria Senese, Policlinico Le Scotte, Viale Bracci, 16, 53100 Siena, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Silvia","family":"Bianchi","sequence":"additional","affiliation":[{"name":"Department of Medicine, Surgery and Neurosciences, University of Siena, 53100 Siena, Italy"},{"name":"UOC Neurologia e Malattie Neurometaboliche, Azienda Ospedaliero-Universitaria Senese, Policlinico Le Scotte, Viale Bracci, 16, 53100 Siena, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Simona","family":"Salvatore","sequence":"additional","affiliation":[{"name":"Department of Medicine, Surgery and Neurosciences, University of Siena, 53100 Siena, Italy"},{"name":"UOC Neurologia e Malattie Neurometaboliche, Azienda Ospedaliero-Universitaria Senese, Policlinico Le Scotte, Viale Bracci, 16, 53100 Siena, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0484-3799","authenticated-orcid":false,"given":"Anna","family":"Rubegni","sequence":"additional","affiliation":[{"name":"Molecular Medicine for Neurodegenerative and Neuromuscular Disease Unit, IRCCS Stella Maris Foundation, 56128 Pisa, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gianna","family":"Berti","sequence":"additional","affiliation":[{"name":"Department of Medicine, Surgery and Neurosciences, University of Siena, 53100 Siena, Italy"},{"name":"UOC Neurologia e Malattie Neurometaboliche, Azienda Ospedaliero-Universitaria Senese, Policlinico Le Scotte, Viale Bracci, 16, 53100 Siena, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Patrizia","family":"Formichi","sequence":"additional","affiliation":[{"name":"Department of Medicine, Surgery and Neurosciences, University of Siena, 53100 Siena, Italy"},{"name":"UOC Neurologia e Malattie Neurometaboliche, Azienda Ospedaliero-Universitaria Senese, Policlinico Le Scotte, Viale Bracci, 16, 53100 Siena, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nicola","family":"De Stefano","sequence":"additional","affiliation":[{"name":"Department of Medicine, Surgery and Neurosciences, University of Siena, 53100 Siena, Italy"},{"name":"UOC Neurologia e Malattie Neurometaboliche, Azienda Ospedaliero-Universitaria Senese, Policlinico Le Scotte, Viale Bracci, 16, 53100 Siena, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alessandro","family":"Malandrini","sequence":"additional","affiliation":[{"name":"Department of Medicine, Surgery and Neurosciences, University of Siena, 53100 Siena, Italy"},{"name":"UOC Neurologia e Malattie Neurometaboliche, Azienda Ospedaliero-Universitaria Senese, Policlinico Le Scotte, Viale Bracci, 16, 53100 Siena, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2256-0482","authenticated-orcid":false,"given":"Diego","family":"Lopergolo","sequence":"additional","affiliation":[{"name":"Department of Medicine, Surgery and Neurosciences, University of Siena, 53100 Siena, Italy"},{"name":"UOC Neurologia e Malattie Neurometaboliche, Azienda Ospedaliero-Universitaria Senese, Policlinico Le Scotte, Viale Bracci, 16, 53100 Siena, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,2,10]]},"reference":[{"key":"ref_1","first-page":"207","article-title":"LGMD. 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