Author/Editor		Gorenjak, Maksimiljan
Title		Vloga fibroblastnega rastnega faktorja 23 (FGF23) v homeostazi fosfata
Translated title		The role of fibroblast growth factor 23 (FGF23) in phosphate homeostasis
Type		članek
Source		In: Monografija IV. osteoloških dnevov z mednarodno udeležbo Maribor : Univerzitetni klinični center
Publication year		2013
Volume		str. 115-122
Language		slv
Abstract		FGF23 je ključni modulator homeostaze fosfata. S svojim specifičnim delovanjem na celice ledvičnih tubulov pospešuje izločanje fosfata z urinom. Hkrati zavira nastanek aktivne oblike vitamina D in pospešuje njeno presnovo v manj aktivni metabolit. Vse omenjene aktivnosti vodijo v znižanje plazemske koncentracije fosfata. FGF23 izločajo osteociti in osteoblasti kosti kot odgovor na povišano koncentracijo fosfata ali aktivne oblike vitamina D v krvi. Pri KLB predstavlja FGF23 kompenzacijski mehanizem, ki znižuje serumsko koncentracijo fosfata. Z napredovanjem bolezni in izgubo veznega elementa proteina Klotho, ta mehanizem popušča. Merjenje FGF23 v krvi predstavlja pomembno diagnostično sredstvo za laboratorijsko diagnostiko bolnikov z različnimi motnjami v homeostazi fosfata. Uporaba občutljive tehnologije določanja FGF23 omogoča nove informacije in vpogled v regulacijo metabolizma kosti in mineralov.FGF23 is the key modulator of phosphate homeostasis. FGF23 increases fractional excretion of phosphate by the kidney with specific actionon the cells of tubuli. It also decreases production of the active form of vitamine D, 1,25-dihydroxyvitamin D, by decreasing the activity of enzyme responsible for its formation (1-- hydroxylase, 24-hydroxylase). All mentioned activities lead to decreased plasma phosphate. FGF23 is secreted by bone cells, osteocytes and osteoblasts, in response to incresed plasma phosphate or increased plasma1,25-dihydroxyvitamin D. In chronic kidney disease FGF23 increases in a compensatory mechanism to counter increasing plasma phosphate. As kidney failure deteriorates further, protein Klotho is lost and responsiveness to FGF23 declines. The measurement of FGF23 levels in the blood is likely to provide an important diagnostic tool for the laboratory evaluation of patients with a variety of different hypophosphatemic and hyperphosphatemic disorders. Furthermore, the sensitive measurement of FGF23 is likely to provide novel insights into the regulation of bone and mineral metabolism.
Keywords		fosfat homeostaza FGF23 os kosti-ledvica phosphate homeostasis FGF23 bone-kidney axis