Curcumin inhibits the activity of ABCG2/BCRP1, a multidrug resistance-linked ABC drug transporter in mice.
OBJECTIVE
To evaluate the in vivo efficacy of curcumin as an inhibitor of the multidrug-resistance-linked ATP Binding Cassette (ABC) drug transporter, ABCG2.


METHODS
Photoaffinity labeling with [125I]-iodoarylazidoprazosin was used to characterize the interaction of sulfasalazine, a substrate of the mouse ABCG2, with human ABCG2. In addition, the inhibitory effect of curcumin on ABCG2 was evaluated in brain capillaries from rats. Furthermore, the effect of curcumin on absorption of orally administered sulfasalazine in wild-type and abcg2-/- mice was also determined.


RESULTS
Sulfasalazine interacted at the drug-substrate site(s) of human ABCG2. Curcumin inhibited ABCG2 activity at nanomolar concentrations at the rat blood-brain barrier in the ex vivo assay. Based on studies in wild type and abcg2-/- mice, we observed that oral curcumin increased Cmax and relative bioavailability of sulfasalazine by selectively inhibiting ABCG2 function.


CONCLUSIONS
This study validates our previous in vitro results with human ABCG2 (Chearwae et al., Mol. Cancer Ther. 5:1995-2006, 2006) and provides the first in vivo evidence for the inhibition by curcumin of ABCG2-mediated efflux of sulfasalazine in mice. Based on these studies, we propose that non-toxic concentrations of curcumin may be used to enhance drug exposure when the rate-limiting step of drug absorption and/or tissue distribution is impacted by ABCG2.
Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, Maryland, 20892-4256, USA.
Suneet
S
Shukla
Hani
H
Zaher
Anika
A
Hartz
Björn
B
Bauer
Joseph A
JA
Ware
Suresh V
SV
Ambudkar
D018435:ATP Binding Cassette Transporter, Subfamily B / Q000172:deficiency / Q000235:genetics; D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2; D018528:ATP-Binding Cassette Transporters / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D000284:Administration, Oral; D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D001386:Azides / Q000378:metabolism; D001682:Biological Availability; D001812:Blood-Brain Barrier / Q000187:drug effects* / Q000378:metabolism; D001896:Boron Compounds / Q000378:metabolism; D045744:Cell Line, Tumor; D003474:Curcumin / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D019008:Drug Resistance, Neoplasm / Q000187:drug effects; D006801:Humans; D051379:Mice; D018345:Mice, Knockout; D009363:Neoplasm Proteins / Q000037:antagonists & inhibitors; D011224:Prazosin / Q000031:analogs & derivatives / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D012460:Sulfasalazine / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics
C116614:ABCG2 protein, human; D018435:ATP Binding Cassette Transporter, Subfamily B; D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2; D018528:ATP-Binding Cassette Transporters; C501412:Abcg2 protein, mouse; C489249:Abcg2 protein, rat; D000972:Antineoplastic Agents, Phytogenic; D001386:Azides; C412306:BODIPY-FL prazosin; D001896:Boron Compounds; D009363:Neoplasm Proteins; D012460:Sulfasalazine; C041552:azidoprazosin; C095122:multidrug resistance protein 3; D003474:Curcumin; D011224:Prazosin