The Effects of Culture Conditions on CYP3A4 and MDR1 mRNA Induction by 1α,25-Dihydroxyvitamin D3 in Human Intestinal Cell Lines, Caco-2 and LS180†

Abstract

To evaluate an in vitro model suitable for investigating intestinal first-pass drug metabolism, CYP3A4 and MDR1 mRNA induction by 1alpha,25-dihydroxyvitamin D(3) (VD3) was examined in two human intestinal cell lines, Caco-2 and LS180, under various culture conditions. CYP3A4 mRNA expression was induced by 100 nM VD3 at levels between 234-549 times above normal in Caco-2 cells for 2 weeks and by 74-200 times above normal in LS180 cells for 2 days. The CYP3A4 induction effect of 250 nM VD3 was similar to or slightly higher than that of 100 nM VD3 in both Caco-2 and LS180 cells. Also, CYP3A4 was induced in Caco-2 and LS180 cells when they were cultured on a polystyrene plate slightly less than when they were cultured on a porous membrane. The increase in fetal bovine serum (FBS) content in the culture medium resulted in little or only slight increase of CYP3A4 induction in both Caco-2 and LS180 cells. MDR1 mRNA expression was marginally increased by VD3 in LS180 cells, but not in Caco-2 cells, and neither increased FBS content nor use of a porous membrane significantly affected MDR1 induction in LS180 cells. The transepithelial electrical resistance of LS180 cells was almost zero, whereas that of Caco-2 cells was high and was marginally decreased by VD3. These findings indicate that Caco-2 cells cultured on a porous membrane with 100 nM VD3 for 2 weeks may be used as a model to investigate the intestinal absorption and first-pass metabolism of drugs, while LS180 cells may be utilized to elucidate the mechanisms which regulate intestinal CYP3A4 mRNA expression.

Vitamin D and colon cancer

“…One of them is the drug efflux pump multi-drug resistance protein (MDR)-1, which is located in the enterocyte apical membrane (Pfrunder et al 2003, Aiba et al 2005). 1,25(OH) 2 D 3 also modulates the expression of members of the multi-drug resistanceassociated protein (MRP) family, which are involved in the transport of conjugated and unconjugated bile acids, and also in that of glutathione and sulphate conjugates (McCarthy et al 2005).…”

Stereoselective Metabolism of Carvedilol by the .BETA.-Naphthoflavone-Inducible Enzyme in Human Intestinal Epithelial Caco-2 Cells

“…26) Recently, Caco-2 cells treated with VD 3 have been utilized to investigate intestinal drug metabolism by CYP3A4. 11,19) That is, we previously reported that the expression level of CYP3A4 mRNA in Caco-2 cells treated with 250 nM VD 3 was more than 300-fold higher than that in non-treated cells. 11) In fact, Schmiedlin-Ren et al reported that midazolam was metabolized significantly in Caco-2 cells treated with VD 3 .…”

“…Treatment of Caco-2 cells with b-NF and VD 3 induces UGTs and CYP3A4, respectively. 11,14,15,19,20) We, therefore, also evaluated changes in the metabolic rate of Rand S-carvedilol in b-NF-and VD 3 -treated Caco-2 cells.…”

“…Recently, however, it has been reported that CYP3A4 in Caco-2 cells is induced by 1a,25-dihydroxyvitamin D 3 (VD 3 ). 11,19) The finding suggests that this cell line may also be utilized to investigate intestinal drug metabolism by CYP3A4. In the present study, we investigated whether carvedilol is metabolized stereoselectively in Caco-2 cells, and also evaluated the changes in the metabolic rate of carvedilol in b-NF-and VD 3 -treated Caco-2 cells.…”

“…It also expresses various transporters and efflux pumps such as P-glycoprotein. 11,12) Therefore, it has been utilized to examine the mechanism responsible for the intestinal absorption of various compounds. 12,13) In addition, several UGTs, such as UGT1A1, 1A6, and 2B7, are expressed in Caco-2 cells, and the expression of some UGTs is induced by aromatic hydrocarbon receptor (AhR) ligands, such as b-naphthoflavone (b-NF).…”