Ursodeoxycholic acid avoids the oxidative stress caused by sodium deoxycholate in intestine: implications on Ca2+ absorption

TOLOSA DE TALAMONI N; RODRIGUEZ V; RIVOIRA M; MARCHIONATTI A; PÉREZ A

Bs As

Congreso; Free radicals 2013; 2013

We have demonstrated that sodium deoxycholate (NaDOC) inhibits the intestinal Ca2+ absorption. The aim of this study was to find out if ursodeoxycholic acid (UDCA) could block this effect. Adult chicks were used: controls, treated with NaDOC, UDCA and UDCA + NaDOC. Intestinal Ca2+absorption was measured by the ligated intestinal loop technique. Glutathione (GSH), carbonyl content, mitochondrial swelling and antioxidant enzymes were determined by spectrophotometry. Ca2+-ATPase (PMCA), Na+/Ca+2 exchanger (NCX1) and calbindin D28K (CB) protein and gene expressions were analyzed by Western blot and RT-qPCR. UDCA alone increased the intestinal Ca2+ absorption and the combined treatment avoided the inhibitory effect caused by NaDOC. UDCA increased the protein and gene expression of PMCA, NCX1 and CB and the combined treatment did not alter the control values. NaDOC decreased the GSH content and increased protein carbonyl content and SOD activity. NaDOC altered the mitochondrial swelling, which was avoided by UDCA. In conclusion, UDCA promotes intestinal Ca2+ absorption. The combined treatment avoids the inhibitory effect of NaDOC because the oxidative stress is blocked. The stimulatory effect of UDCA on the intestinal Ca2+ absorption would be through an increase in gene and protein expression of molecules involved in the transcellular Ca2+pathway.