caa a22 4500 606236783 CHVBK 20210128101249.0 cr unu---uuuuu 210128e20150501xx s 000 0 eng 10.1007/s11010-015-2336-z doi (NATIONALLICENCE)springer-10.1007/s11010-015-2336-z The mechanism of oxythiamine-induced collagen biosynthesis in cultured fibroblasts [Elektronische Daten] [Lukasz Szoka, Ewa Karna, Jerzy Palka] The oxythiamine (OXY) is antivitamin of thiamine. The finding that OXY increases the cytoplasmic concentration of pyruvate, known to enhance collagen biosynthesis, led us to investigate the mechanism of this antivitamin action on collagen biosynthesis in cultured human skin fibroblasts. Confluent fibroblasts were treated with micromolar concentrations (30-1,000µM) of OXY for 24 and 48h. It was found that OXY-dependent increase in collagen biosynthesis was accompanied by parallel increase in prolidase activity and level, compared to untreated cells. Since phosphoenolpyruvate (PEP) is known as an inhibitor of prolidase—the enzyme that plays important role in collagen biosynthesis, the mechanism of pyruvate interconversion was considered as a regulatory switch in collagen biosynthesis. In fact, 3-MPA, specific inhibitor of phosphoenolpyruvate carboxykinase (PEPCK), contributed to up-regulation of prolidase activity, suggesting that down-regulation of PEP formation is an underlying mechanism. Since collagen biosynthesis and prolidase activity are regulated by signal induced by activated α2β1 integrin receptor as well as insulin-like growth factor-I receptor (IGF-IR), the expression of these receptors was measured by Western immunoblot analysis. The exposure of the cells to OXY contributed to decrease in IGF-IR, α2β1 integrin receptor, pERK1/2, and NF-κB p65 expressions. It was accompanied by increase in total ERK1/2 expression and induction of phosphorylation of Akt protein. The data suggest that OXY-dependent increase of collagen biosynthesis in cultured human skin fibroblasts results from activation of prolidase activity and level, induction in pAkt expression and down-regulation of pERK1/2 and NF-κB p65, the known inhibitor of collagen gene expression. The Author(s), 2015 Oxythiamine nationallicence Collagen biosynthesis nationallicence Prolidase nationallicence ERK1/2 nationallicence Akt nationallicence NF- κ B p65 nationallicence Szoka Lukasz Department of Medicinal Chemistry, Medical University of Bialystok, Mickiewicza 2 D, 15-222, Bialystok, Poland aut Karna Ewa Department of Medicinal Chemistry, Medical University of Bialystok, Mickiewicza 2 D, 15-222, Bialystok, Poland aut Palka Jerzy Department of Medicinal Chemistry, Medical University of Bialystok, Mickiewicza 2 D, 15-222, Bialystok, Poland aut Molecular and Cellular Biochemistry Springer US; http://www.springer-ny.com 403/1-2(2015-05-01), 51-60 0300-8177 403:1-2<51 2015 403 11010 https://doi.org/10.1007/s11010-015-2336-z text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s11010-015-2336-z text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Szoka Lukasz Department of Medicinal Chemistry, Medical University of Bialystok, Mickiewicza 2 D, 15-222, Bialystok, Poland aut NATIONALLICENCE 700 1- Karna Ewa Department of Medicinal Chemistry, Medical University of Bialystok, Mickiewicza 2 D, 15-222, Bialystok, Poland aut NATIONALLICENCE 700 1- Palka Jerzy Department of Medicinal Chemistry, Medical University of Bialystok, Mickiewicza 2 D, 15-222, Bialystok, Poland aut NATIONALLICENCE 773 0- Molecular and Cellular Biochemistry Springer US; http://www.springer-ny.com 403/1-2(2015-05-01), 51-60 0300-8177 403:1-2<51 2015 403 11010