{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,1]],"date-time":"2026-06-01T18:13:11Z","timestamp":1780337591534,"version":"3.54.1"},"reference-count":49,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2021,11,2]],"date-time":"2021-11-02T00:00:00Z","timestamp":1635811200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100007397","name":"Charles University","doi-asserted-by":"publisher","award":["GA UK No. 410121"],"award-info":[{"award-number":["GA UK No. 410121"]}],"id":[{"id":"10.13039\/100007397","id-type":"DOI","asserted-by":"publisher"}]},{"name":"the Ministry of Health of the Czech Republic","award":["AZV No. 17-31564A"],"award-info":[{"award-number":["AZV No. 17-31564A"]}]},{"name":"Krajska zdravotni a.s., Usti nad Labem, Czech Republic","award":["No. IGA-KZ-217116003"],"award-info":[{"award-number":["No. IGA-KZ-217116003"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Congenital clubfoot is a complex musculoskeletal deformity, in which a stiff, contracted tissue forms in the medial part of the foot. Fibrotic changes are associated with increased collagen deposition and lysyl oxidase (LOX)-mediated crosslinking, which impair collagen degradation and increase the tissue stiffness. First, we studied collagen deposition, as well as the expression of collagen and the amount of pyridinoline and deoxypyridinoline crosslinks in the tissue of relapsed clubfoot by immunohistochemistry, real-time PCR, and enzyme-linked immunosorbent assay (ELISA). We then isolated fibroblast-like cells from the contracted tissue to study the potential inhibition of these processes in vitro. We assessed the effects of a LOX inhibitor, \u03b2-aminopropionitrile (BAPN), on the cells by a hydroxyproline assay, ELISA, and Second Harmonic Generation imaging. We also evaluated the cell-mediated contraction of extracellular matrix in 3D cell-populated collagen gels. For the first time, we have confirmed significantly increased crosslinking and excessive collagen type I deposition in the clubfoot-contracted tissue. We successfully reduced these processes in vitro in a dose-dependent manner with 10\u201340 \u00b5g\/mL of BAPN, and we observed an increasing trend in the inhibition of the cell-mediated contraction of collagen gels. The in vitro inhibitory effects indicate that BAPN has good potential for the treatment of relapsed and resistant clubfeet.<\/jats:p>","DOI":"10.3390\/ijms222111903","type":"journal-article","created":{"date-parts":[[2021,11,2]],"date-time":"2021-11-02T12:39:42Z","timestamp":1635856782000},"page":"11903","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Increased Collagen Crosslinking in Stiff Clubfoot Tissue: Implications for the Improvement of Therapeutic Strategies"],"prefix":"10.3390","volume":"22","author":[{"given":"Jarmila","family":"Knitlova","sequence":"first","affiliation":[{"name":"Institute of Physiology of the Czech Academy of Sciences, Videnska 1083, 142 20 Prague, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4955-4093","authenticated-orcid":false,"given":"Martina","family":"Doubkova","sequence":"additional","affiliation":[{"name":"Institute of Physiology of the Czech Academy of Sciences, Videnska 1083, 142 20 Prague, Czech Republic"},{"name":"Second Faculty of Medicine, Charles University, V Uvalu 84, 150 06 Prague, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Adam","family":"Eckhardt","sequence":"additional","affiliation":[{"name":"Institute of Physiology of the Czech Academy of Sciences, Videnska 1083, 142 20 Prague, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Martin","family":"Ostadal","sequence":"additional","affiliation":[{"name":"Department of Orthopaedics, First Faculty of Medicine, Charles University and Na Bulovce Hospital, Budinova 2, 180 81 Prague, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jana","family":"Musilkova","sequence":"additional","affiliation":[{"name":"Institute of Physiology of the Czech Academy of Sciences, Videnska 1083, 142 20 Prague, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1818-9484","authenticated-orcid":false,"given":"Lucie","family":"Bacakova","sequence":"additional","affiliation":[{"name":"Institute of Physiology of the Czech Academy of Sciences, Videnska 1083, 142 20 Prague, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3855-0038","authenticated-orcid":false,"given":"Tomas","family":"Novotny","sequence":"additional","affiliation":[{"name":"Department of Orthopaedics, University J.E. Purkinje and Masaryk Hospital, 401 13 Usti nad Labem, Czech Republic"},{"name":"Department of Histology and Embryology, Second Faculty of Medicine, Charles University, 150 06 Prague, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,11,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"269","DOI":"10.1111\/tmi.12833","article-title":"Birth Prevalence of Congenital Talipes Equinovarus in Low- and Middle-Income Countries: A Systematic Review and Meta-Analysis","volume":"22","author":"Smythe","year":"2017","journal-title":"Trop. Med. Int. Health"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"e462","DOI":"10.1097\/BPO.0000000000001191","article-title":"Clubfoot Etiology: A Meta-Analysis and Systematic Review of Observational and Randomized Trials","volume":"38","author":"Chen","year":"2018","journal-title":"J. Pediatr. 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