MDR1 and OAT1/OAT3 mediate the drug-drug interaction between puerarin and methotrexate.
OBJECTIVE
To conduct in vivo and in vitro experiments to investigate puerarin (PUR), an isoflavone C-glyoside, and elucidate its ability to alter methotrexate (MTX) transport and pharmacokinetics.


METHODS
In vivo absorption studies, in vitro everted intestinal sac preparation, kidney slices in rats and bi-directional transport assay with mock-/MDCK-MDR1 cells, uptake studies in HEK293-OAT1/3 cells were employed to evaluate the interaction.


RESULTS
In vivo and in vitro MTX absorption in rats were enhanced in combination with PUR. PUR inhibited digoxin efflux transport in MDCK-MDR1 monolayers with an IC50 value of 1.6 ± 0.3 μM, suggesting that the first target of drug interaction was MDR1 in the intestine during the absorption process. MTX renal clearance decreased significantly after simultaneous intravenous administration. MTX uptake in rat kidney slices and HEK293-OAT1/3 cells were markedly inhibited by PUR, suggesting that the second target of drug interaction was OATs located in the kidney. Moreover, concomitant administration of PUR reduced renal MTX accumulation and plasma levels of creatinine and BUN.


CONCLUSIONS
Co-administration of PUR enhanced MTX exposure by inhibition of intestinal MDR1 and renal OAT1/3. Although the renal damage of MTX was improved by PUR, the high level exposure of MTX should be cautious in the clinical usage.
Department of Clinical Pharmacology, College of Pharmacy, Dalian Medical University, 9 West Section, Lvshun South Road Lvshunkou District, Dalian, 116044, China.
Qi
Q
Liu
Changyuan
C
Wang
Qiang
Q
Meng
Xiaokui
X
Huo
Huijun
H
Sun
Jinyong
J
Peng
Xiaochi
X
Ma
Pengyuan
P
Sun
Kexin
K
Liu
D018435:ATP Binding Cassette Transporter, Subfamily B / Q000502:physiology; D000818:Animals; D002460:Cell Line; D002853:Chromatography, Liquid; D004285:Dogs; D004347:Drug Interactions; D057809:HEK293 Cells; D006801:Humans; D007529:Isoflavones / Q000494:pharmacology*; D008297:Male; D008727:Methotrexate / Q000494:pharmacology*; D027362:Organic Anion Transport Protein 1 / Q000502:physiology*; D029362:Organic Anion Transporters, Sodium-Independent / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D053719:Tandem Mass Spectrometry
C513055:ABCB1 protein, human; D018435:ATP Binding Cassette Transporter, Subfamily B; D007529:Isoflavones; D027362:Organic Anion Transport Protein 1; D029362:Organic Anion Transporters, Sodium-Independent; C114338:organic anion transport protein 3; D008727:Methotrexate; C033607:puerarin