P-glycoprotein-170 inhibition significantly reduces cortisol and ciclosporin efflux from human intestinal epithelial cells and T lymphocytes.
Aliment Pharmacol Ther
; 16(5): 1021-31, 2002 May.
Article
in En
| MEDLINE
| ID: mdl-11966513
AIM: To assess the role of P-glycoprotein-170 (P-gp) in transporting cortisol and ciclosporin from human intestinal epithelium and T lymphocytes. METHODS: The effect of P-gp inhibitors (verapamil, 0-100 microM; PSC 833, 0-20 microM) on the intracellular accumulation of 3H-cortisol and 3H-ciclosporin was studied in confluent layers of human Caco-2 cells (n=6), a P-gp-dependent absorptive intestinal epithelial cell phenotype, and moderately resistant MDRhigh CEM/VBL 100 T cells (n=6). The transport of 3H-vinblastine, a strong multidrug resistance (MDR) substrate, and 3H-progesterone, a poor MDR substrate, was also studied. RESULTS: Caco-2 cells had a 2.4-, 6.6-, 6.7- and 1.03-fold higher net basal to apical transport (efflux) of 3H-cortisol, 3H-ciclosporin, 3H-vinblastine and 3H-progesterone, respectively. PSC 833 (20 microM) reduced cortisol efflux by 69% (0.23 +/- 0.04 to 0.07 +/- 0.01 pmol/cm2/h, P < 0.05) and ciclosporin efflux by 76% (11.1 +/- 1.4 to 2.7 +/- 0.6 pmol/cm2/h, P < 0.001). MDRlow CEM T cells had a 1.4-, 1.9-, 3.2- and 1.02-fold higher intracellular accumulation of cortisol, ciclosporin, vinblastine and progesterone than MDRhigh CEM/VBL 100 T cells. Increasing concentrations of PSC 833 (> 0.1 microM) and verapamil (> 1 microM) restored the intracellular level of 3H-cortisol and 3H-ciclosporin in MDRhigh CEM/VBL 100 T cells to that of MDRlow CEM cells with little change in accumulation in the MDRlow parental cell line. CONCLUSIONS: P-gp inhibitors significantly increase intracellular cortisol and ciclosporin levels in human intestinal epithelium and T lymphocytes in a dose-dependent manner, demonstrating a potential mechanism for overcoming poor response to immunosuppressant therapy in refractory inflammatory bowel disease.
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Collection:
01-internacional
Database:
MEDLINE
Main subject:
Calcium Channel Blockers
/
T-Lymphocytes
/
Verapamil
/
Cyclosporine
/
ATP Binding Cassette Transporter, Subfamily B, Member 1
/
Immunosuppressive Agents
/
Intestinal Mucosa
/
Anti-Inflammatory Agents
Limits:
Humans
Language:
En
Journal:
Aliment Pharmacol Ther
Journal subject:
FARMACOLOGIA
/
GASTROENTEROLOGIA
/
TERAPIA POR MEDICAMENTOS
Year:
2002
Document type:
Article
Affiliation country:
Estados Unidos
Country of publication:
Reino Unido