{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,4]],"date-time":"2026-04-04T11:11:10Z","timestamp":1775301070551,"version":"3.50.1"},"reference-count":0,"publisher":"Frontiers Media SA","issue":"3","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J Pharm Pharm Sci"],"abstract":"<jats:p>Purpose. Tryptanthrin, an indole quinazoline alkaloid with multiple medical activities, has been recently under preclinical development as an anti-tuberculosis and anti-tumor drug. The aims of this study are to characterize the intestinal transport of tryptanthrin in Caco-2 cells,   to determine whether P-glycoprotein (P-gp) and multidrug resistance-associated protein 2 (MRP2) are involved in this issue, and to evaluate the potential influence of tryptanthrin on the function of P-gp and MRP2. Methods. Transport assays of tryptanthrin were performed in Caco-2 monolayers with or without the supplement of P-gp and MRP2 inhibitors. Transport assays of P-gp and MRP2 substrates were also performed in the presence of tryptanthrin. The effect of tryptanthrin on the expression of P-gp and MRP2 was analyzed by reverse transcriptase-PCR. Results. Both absorption and secretion of tryptanthrin were concentration-independent at a low concentration range of 0.8\u201320 \u00b5M. The apparent permeability (Papp) for the apical (AP) to basolateral (BL) was 6.138 \u00b1 0.291 \u00d7 10-5. The ratio of Papp (BL\u2192AP) to Papp (AP\u2192BL) was 0.77, suggesting greater permeability in the absorptive direction. Both the P-gp inhibitor, verapamil, and the MRP2 inhibitor, glibenclamide, didn\u2019t affect the efflux transport of tryptanthrin. The efflux transport of the P-gp substrate, digoxin, and the MRP2 substrate, pravastatin sodium, decreased when tryptanthrin was present. However, tryptanthrin didn\u2019t change the expression of P-gp and MRP2. Conclusions. Tryptanthrin was well absorbed across the Caco-2 monolayers, and its transepithelial transports were dominated by passive diffusion. Tryptanthrin was not a substrate, but a potential inhibitor of P-gp and MRP2.\r\n\r\nThis article is open to POST-PUBLICATION REVIEW. Registered readers (see \u201cFor Readers\u201d) may comment by clicking on ABSTRACT on the issue\u2019s contents page.<\/jats:p>","DOI":"10.18433\/j3501w","type":"journal-article","created":{"date-parts":[[2016,3,18]],"date-time":"2016-03-18T23:07:20Z","timestamp":1458342440000},"page":"325","source":"Crossref","is-referenced-by-count":34,"title":["Transport Characteristics of Tryptanthrin and its Inhibitory Effect on P-gp and MRP2 in Caco-2 Cells"],"prefix":"10.3389","volume":"14","author":[{"given":"Xingang","family":"Zhu","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xuelian","family":"Zhang","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Guo","family":"Ma","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Junkai","family":"Yan","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Honghai","family":"Wang","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Qing","family":"Yang","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2011,8,8]]},"container-title":["Journal of Pharmacy &amp; Pharmaceutical Sciences"],"original-title":[],"deposited":{"date-parts":[[2023,1,13]],"date-time":"2023-01-13T13:33:44Z","timestamp":1673616824000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.library.ualberta.ca\/jpps\/index.php\/JPPS\/article\/view\/10147"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2011,8,8]]},"references-count":0,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2011,7,4]]}},"URL":"https:\/\/doi.org\/10.18433\/j3501w","relation":{},"ISSN":["1482-1826","1482-1826"],"issn-type":[{"value":"1482-1826","type":"electronic"},{"value":"1482-1826","type":"print"}],"subject":[],"published":{"date-parts":[[2011,8,8]]}}}