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| 1.
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Shimizu, Takuya ; Kijima, Ai ; Masuo, Yusuke ; Ishimoto, Takahiro ; Sugiura, Tomoko ; Takahashi, Saki ; Nakamichi, Noritaka ; Kato, Yukio
概要:
5-Aminosalicylic acid (5-ASA) is an orally administered therapeutic agent for inflammatory bowel diseases, such as ulcer
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ative colitis and Crohn’s disease. We hypothesized that the absorption of 5-ASA is mediated by the polyspecific carnitine/organic cation transporter (OCTN1/SLC22A4), based on the similarity of chemical structure between 5-ASA and other OCTN1 substrates. Therefore, we examined the involvement of this transporter in the disposition of 5-ASA in vivo by using octn1 gene knockout (octn1−/−) mice. After oral administration of 5-ASA, the plasma concentrations of 5-ASA and its primary metabolite, N-acetyl-5-aminosalicylate (Ac-5-ASA), in octn1−/− mice were much lower than those in wild-type mice. The time required to reach maximum plasma concentration was also delayed in octn1−/− mice. On the other hand, the plasma concentration profiles of both 5-ASA and Ac-5-ASA after intravenous administration of 5-ASA (bolus or infusion) were similar in the two strains. Uptake of 5-ASA from the apical to the basal side of isolated small-intestinal tissues of octn1−/− mice, determined in an Ussing-type chamber, was lower than that in wild-type mice. Further, uptake of 5-ASA in HEK293 cells stably transfected with the OCTN1 gene, assessed as the sum of cell-associated 5-ASA and Ac-5-ASA, was higher than that in HEK293 cells transfected with the vector alone. Overall, these results indicate that OCTN1 is involved, at least in part, in the gastrointestinal absorption of 5-ASA.
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| 2.
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Masuo, Yusuke ; Nagamori, Shushi ; Hasegawa, Aoi ; Hayashi, Kazuki ; Isozumi, Noriyoshi ; Nakamichi, Noritaka ; Kanai, Yoshikatsu ; Kato, Yukio
概要:
Purpose: Monoamine oxidases (MAOs) are non-CYP enzymes that contribute to systemic elimination of therapeutic agents, an
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d localized on mitochondrial membranes. The aim of the present study was to validate quantitative estimation of metabolic clearance of MAO substrate drugs using human liver microsomes (HLMs). Methods: Three MAO substrate drugs, sumatriptan, rizatriptan and phenylephrine, as well as four CYP substrates were selected, and their disappearance during incubation with HLMs or mitochondria (HLMt) was measured. Metabolic clearance (CL) was then calculated from the disappearance curve. Results: CL obtained in HLMs for sumatriptan and a typical MAO substrate serotonin was correlated with that obtained in HLMt among ten human individual livers. Hepatic intrinsic clearance (CLint,vitro) estimated from CL in HLMs was 14–20 and 2–5 times lower than in vivo hepatic intrinsic clearance (CLint,vivo) obtained from literature for MAO and CYP substrates, respectively. Utilization of HLMs for quantitatively assessing metabolic clearance of MAO substrates was further validated by proteomics approach which has revealed that numerous proteins localized on inner and outer membranes of mitochondria were detected in both HLMs and HLMt. Conclusion: CLint,vitro values of MAO substrate drugs can be quantitatively estimated with HLMs and could be used for semi-quantitative prediction of CLint,vivo values. © 2017 Springer Science+Business Media New York<br />Embargo Period 12 months
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| 3.
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Hashimoto, Naoto ; Nakamichi, Noritaka ; Yamazaki, Erina ; Oikawa, Masashi ; Masuo, Yusuke ; Schinkel, Alfred H. ; Kato, Yukio
概要:
ATP binding cassette transporters, P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP), are expressed in s
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kin, but their involvement in transdermal absorption of clinically used drugs remains unknown. Here, we examined their role in transdermal absorption of corticosteroids. Skin and plasma concentrations of dexamethasone after dermal application were reduced in P-gp and BCRP triple-knockout (Mdr1a/1b/Bcrp−/−) mice. The skin concentration in Mdr1a/1b/Bcrp−/− mice was reduced in the dermis, but not in the epidermis, indicating that functional expression of these transporters in skin is compartmentalized. Involvement of these transporters in dermal transport of dexamethasone was also supported by the observation of a higher epidermal concentration in Mdr1a/1b/Bcrp−/− than wild-type mice during intravenous infusion. Transdermal absorption after dermal application of prednisolone, but not methylprednisolone or ethinyl estradiol, was also lower in Mdr1a/1b/Bcrp−/− than in wild-type mice. Transport studies in epithelial cell lines transfected with P-gp or BCRP showed that dexamethasone and prednisolone are substrates of P-gp, but are minimally transported by BCRP. Thus, our findings suggest that P-gp is involved in transdermal absorption of at least some corticosteroids in vivo. P-gp might be available as a target for inhibition in order to deliver topically applied drugs and cosmetics in a manner that minimizes systemic exposure. © 2017 Elsevier B.V.<br />Embargo Period 12 months
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| 4.
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Shimizu, Takuya ; Kijima, Ai ; Masuo, Yusuke ; Ishimoto, Takahiro ; Sugiura, Tomoko ; Takahashi, Saki ; Nakamichi, Noritaka ; Kato, Yukio
概要:
5-Aminosalicylic acid (5-ASA) is an orally administered therapeutic agent for inflammatory bowel diseases, such as ulcer
…
ative colitis and Crohn’s disease. We hypothesized that the absorption of 5-ASA is mediated by the polyspecific carnitine/organic cation transporter (OCTN1/SLC22A4), based on the similarity of chemical structure between 5-ASA and other OCTN1 substrates. Therefore, we examined the involvement of this transporter in the disposition of 5-ASA in vivo by using octn1 gene knockout (octn1−/−) mice. After oral administration of 5-ASA, the plasma concentrations of 5-ASA and its primary metabolite, N-acetyl-5-aminosalicylate (Ac-5-ASA), in octn1−/− mice were much lower than those in wild-type mice. The time required to reach maximum plasma concentration was also delayed in octn1−/− mice. On the other hand, the plasma concentration profiles of both 5-ASA and Ac-5-ASA after intravenous administration of 5-ASA (bolus or infusion) were similar in the two strains. Uptake of 5-ASA from the apical to the basal side of isolated small-intestinal tissues of octn1−/− mice, determined in an Ussing-type chamber, was lower than that in wild-type mice. Further, uptake of 5-ASA in HEK293 cells stably transfected with the OCTN1 gene, assessed as the sum of cell-associated 5-ASA and Ac-5-ASA, was higher than that in HEK293 cells transfected with the vector alone. Overall, these results indicate that OCTN1 is involved, at least in part, in the gastrointestinal absorption of 5-ASA.
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| 5.
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Tang, Yaliang ; Masuo, Yusuke ; Sakai, Yoshio ; Wakayama, Tomohiko ; Sugiura, Tomoko ; Harada, Ryuichi ; Futatsugi, Azusa ; Komura, Takuya ; Nakamichi, Noritaka ; Sekiguchi, Hirotaka ; Sutoh, Keita ; Usumi, Koji ; Iseki, Shoichi ; Kaneko, Shuichi ; Kato, Yukio
概要:
Xenobiotic transporters play key roles in disposition of certain therapeutic agents, although limited information is ava
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ilable on their roles other than pharmacokinetic issues. Here, suppressive effect of multispecific organic cation transporter OCTN1/SLC22A4 on liver fibrosis was proposed in liver injury models. After injection of hepatotoxins such as dimethylnitrosamine (DMN) or concanavalin A, hepatic fibrosis, and oxidative stress, evaluated in terms of Sirius red and 4-hydroxy-2-nonenal staining, respectively, were more severe in liver of octn1/slc22a4 gene knockout (octn1-/-) mice than that in wild-type mice. DMN treatment markedly increased α-smooth muscle actin and F4/80, markers of activated stellate and Kupffer cells, respectively, in liver of octn1-/-, but had less effect in wild-type mice. Thus, octn1/slc22a4 gene deletion results in more severe hepatic fibrosis, oxidative stress, and inflammation. DMN-treated wild-type mice showed increased Octn1 staining and hepatic concentration of its food-derived antioxidant ergothioneine (ERGO). The upregulated Octn1 was co-localized with α-smooth muscle actin. Functional expression of Octn1 was demonstrated in activated human hepatic stellate cell lines, LI90 and LX-2. Provision of ERGO-rich feed ameliorated DMN-induced liver fibrosis and oxidative stress. Overall, Octn1 is upregulated in activated stellate cells, resulting in increased delivery of its substrate antioxidant ERGO and a protective effect against liver fibrosis. © 2016 American Pharmacists Association. Published by Elsevier Inc. All rights reserved.<br />Embargo Period 12 months
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| 6.
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Fujita, Ken-ichi ; Masuo, Yusuke ; Yamazaki, Erina ; Shibutani, Toshiki ; Kubota, Yutaro ; Nakamichi, Noritaka ; Sasaki, Yasutsuna ; Kato, Yukio
概要:
Regorafenib is a multikinase inhibitor orally administered to colorectal cancer patients, and is known to often exhibit
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dermal toxicity. The purpose of this study is to clarify possible involvement of P-glycoprotein and breast cancer resistance protein (BCRP) in the dermal accumulation of regorafenib and its active metabolites M-2 and M-5. Following intravenous administration in triple knockout (Abcb1a/1b/bcrp -/-; TKO) and wild-type (WT) mice, delayed plasma clearance of M-2 and M-5, but not regorafenib, was observed in TKO mice compared to WT mice. Elacridar, an inhibitor of both transporters, also caused delayed clearance of M-2 and M-5, suggesting that these transporters are involved in their elimination. Skin-to-plasma concentration ratios of regorafenib, M-2, and M-5 were significantly higher in TKO mice than in WT mice. Elacridar increased skin-to-plasma and epidermis-to-plasma concentration ratios of regorafenib. Basal-to-apical transport of M-2 and M-5 was observed in LLC-PK1-Pgp and MDCKII/BCRP/PDZK1 cells, which was inhibited by elacridar and the BCRP inhibitor Ko143, respectively. The present findings thus indicate that P-glycoprotein and BCRP are involved in the accumulation of regorafenib and its active metabolites in the skin, by affecting either their systemic exposure or their plasma distribution in the circulating blood. © 2017 American Pharmacists Association®.<br />Embargo Period 12 months
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| 7.
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増尾, 友佑 ; Masuo, Yusuke
概要:
金沢大学医薬保健研究域薬学系<br />肝消失型薬物の一部は、血漿中からの消失が慢性腎障害時に遅延する。そこで、OATP1B1阻害作用を有する生体内化合物を探索したところ、6-OH indoleはOATP1B1を阻害した。血漿中6-OH i
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ndole濃度は、腎障害患者において、正常腎機能患者よりも血漿中濃度が高かった。この化合物によるOATP1B1阻害作用は持続的であり、プレインキュベーション時のみに添加した際にも阻害作用を有した。さらに、本化合物は、ヒト初代培養肝細胞でestrone 3-sulfateの細胞内取り込みを阻害した。本化合物は、慢性腎障害時に血液中に蓄積してOATP1B1の機能阻害を引き起こすことが示唆された。<br />Several uremic tocxins have been proposed to inhibit hepatic uptake transporters. The purpose of this study is to find possible inhibition of OATP1B1 by newly identified uremic toxins, 6-OH indole. 6-OH indole inhibited OATP1B1-mediated uptake of [3H]estrone sulfate in HEK293/OATP1B1 cells. Plasma concentration of 6-OH indole was higher in patients with severe renal failure than that in patients without renal failure. The inhibition pattern of OATP1B1 by 6-OH indole was long-lasting, since its inhibition was maintained after 6-OH indole was washed out. Also, 6-OH indole inhibited uptake of estrone sulfate in primary cultured hepatocytes without changing mRNA expression of OATP1B1. These results suggest that increase of 6-OH indole in plasma during CKD could at least partially explain the delayed elimination of OATP1B1 substrate drugs.<br />研究課題/領域番号:16K18934, 研究期間(年度):2016-04-01 - 2018-03-31
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| 8.
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増尾, 友佑 ; Masuo, Yusuke
概要:
金沢大学医薬保健研究域薬学系<br />一部の肝消失型薬物は、血中消失が慢性腎障害患者で遅延し、この原因として患者血漿中で蓄積する一部の尿毒素による肝膜輸送体のdirect inhibitionが報告されているが、他の尿毒素による阻害やdi
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rect inhibition以外の作用は未解明である。本研究では、p-cresyl sulfateによる肝膜輸送体OATP1B1のdirect inhibitionとindoxyl sulfateによるOATP1B1のlong-lasting inhibitionを明らかにした。本研究で明らかになった阻害作用は、慢性腎障害時におけるOATP1B1基質薬の血中消失の遅延を一部説明しうるものである。<br />Several uremic toxins have been proposed to inhibit hepatic uptake transporters. The purpose is to clarify possible long-lasting inhibition of OATP1B1 by uremic toxins. OATP1B1-mediated uptake of [3H]estrone sulfate (E3S) was examined after co-incubation or preincubation with uremic toxins in HEK293/OATP1B1 cells and primary cultured human hepatocytes. Among 21 uremic toxins, indoxyl sulfate (IS), CMPF and p-cresyl sulfate directly inhibited OATP1B1 mediated-uptake of E3S, but only IS exhibited inhibitory effect even after preincubation. Such inhibition of E3S uptake by preincubation with IS was more remarkable than that by its co-incubation, and observed in preincubation time- and concentration-dependent manners. Preincubation with IS also decreased uptake of E3S in human hepatocytes in primary culture. Overall, the long-lasting inhibition in the presence of IS could at least partially explain the delayed elimination of OATP1B1 substrate drugs during severe renal failure.<br />研究課題/領域番号:26860099, 研究期間(年度):2014-04-01 - 2016-03-31
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