• Journal of Pharmaceutical Investigation
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• v.25 no.2
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• pp.101-108
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• 1995

The surface of albumin microspheres could be modified with methotrexate (MTX) by using 1,3-dicyclohexylcarbodiimide (DCC). Surface-modified albumin microspheres entrapping no MTX (SAMS), free MTX (SAMSF) and MTX-bovine serum albumin (BSA) conjugates (SAMSC) were prepared. respectively, and their release characteristics were investigated in the presence of trypsin using a dissolution tester. The mean diameters of all the microspheres were $5{\sim}8\;{\mu}m$, and their shapes was small and uniform. MTX bound tn their surfaces was released slower than the entrapped free MTX, and laster than the entrapped MTX-BSA conjugates. Also, surface-modified MTX was scarcely released in the absence of a proteolytic enzyme. Therefore, the surface-modified MTX may be released rapidly from SAMSC at the target site, and thereafter MTX may be released slowly from the encapsulated MTX-BSA conjugates in SAMSC for a long period.

• Archives of Pharmacal Research
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• v.13 no.2
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• pp.147-150
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• 1990

Methotrexate (MTX)-poly-L-lysine (PLL) conjugate was relatively stable in phosphate buffer of pH 7.4 and in plasma. However, liver homogenate accelerated the release of MTX from the conjugate. Pharmacokinetics and tissue distribution of MTX were compared after intramuscular injection of MTX (treatment I) and MTX-PLL conjugate (treatment II), 10 mg/kg as free MTX to rabbits. The peak concentration of MTX in treatment II were significantly lower than those in treatment I. The amount of MTX excreted in 24-hr urine was significantly reduced in treatment II and it suggested that MTX be more metabolized in treatment II than in treatment I. The amounts of MTX remaining in each organ after 24-hr of intramuscular injection were not significantly different in both treatments.

• Archives of Pharmacal Research
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• v.15 no.2
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• pp.162-168
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• 1992

Release characteristics of five different types of hydrophilic albumin microspheres (HAM) containing different ratios of methotrexate-albumin (MTX-HSA) conjugates to free MTX: 1 : 0 (HAMC), 3 :1 (HAMC 3F), 1 :1 (HAMCF), 1:3 (HAMCF3) and 0 : 1 (HAMF) were investigated in the absence or presence of protease using dissolution tester. In all the HAMs studied except HAMC, the MTX was released bi-exponentially in the absence of protease; an initial fast release period up to approximately 6h, and thereafter the release rate was very much slower. The fast release of MTX from the HAMs (such as HAMC3F, HAMCF, HAMCF3 and HAMF) at the initial phase in probably due to the release of "physically associated" MTX from the core of the HAMs. The initial rate constants were 7.2, 8.7, 8.5 and 5.9 times greater than the second rate constants for HAMF, HAMCF3, HAMCF and HAMC3F, respectively. MTX release from HAMC was very slow and mono-phasic. It was at most 2.2% of the total entrapped amount by 24 h. The protease accelerated the release of MTX from the HAMs. The percentages of MTX released from HAMs up to 24 h were 100, 89.0, 75.0, 66.0 and 61.0% for HAMF, HAMCF3, HAMCF, HAMC3F and HAMC, respectively in the presence of protease and the corresponding values in the absence of protease were 30.2 19.0, 10.0, 6.5 and 2.2%, respectively. In vitro release of MTX in the presence of protease varied according to the ratios of MTX-HSA conjugates to MTX; the data set from HAMF, HAMCF3 and HAMCF fits better to monophasic first-order profile more adequately than to zero-order profile, that of HAMC3 monophasic first-order, and that of HAMC to bi-phasic zero-order. Above results suggested that zero-order release rate can be achieved by adjusting the ratio of MTX-HSA conjugates to MTX in the preparation of HAMs such as HAMC3F.as HAMC3F.

• YAKHAK HOEJI
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• v.36 no.6
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• pp.591-597
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• 1992

The organ distribution of $[^3H]$-methotrexate-lactosaminated bovine serum albumin conjugates ($[^3H]$-MTX-LBSA) was investigated to examine their role as a liver-specific anticancer drug. Synthesis of lactosaminated bovine serum albumin(LBSA) with BSA, lactose and sodium cyanoborohydride through reductive amination was followed by its conjugation with methotrexate (MTX) and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC), thereby synthesizing [$[^3H]$-MTX-LBSA conjugates. Organ distribution and plasma elimination profiles were studied in male Wistar rats after intravenous injection of [$[^3H]$-MTX-LBSA conjugates. The fates of $[^3H]$-MTX and the $[^3H]$-MTX-BSA conjugates´fates were also investigated for comparison. The results showed that the plasma level of $[^3H]$-MTX-LBSA conjugates declined more rapidly than those of $[^3H]$-MTX-BSA and their liver concentration was significantly higher than those of other treatment (p<0.01). In addition, their uptake compared to the amount taken up by the liver (1 : 33.1 at 10 min, 1 : 24.1 at 120 min). All these suggested that MTX-LBSA conjugate is one of the drug delivery system (DDS) that is advanced in concentrating MTX in the liver and minimizing the renal toxicity of MTX.

• Korean Journal of Clinical Pharmacy
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• v.1 no.1
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• pp.1-7
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• 1991

Folates are involved in a variety of important biosynthesis by way of donating one carbon unit. Since folate metabolism was well understood a number of antifol have been developed. Among these antifols, aminopterin was first used in the treatment of childhood leukemia. However due to its toxicity and purity problems. it was immediately replaced by another antifols. methotrexate (MTX). MTX is shown to be active against various malignancies including leukemia breast cancer, osteogenic sarcoma, and head and neck cancer. Clinically, MTX therapy is divided into 3 categories. depeding on the dose administered; low-dose is defined as doses < $80\;mg/m^2$ intermediate-dose as doses $\geqq\;80\;mg/m^2$ and < $1000\;mg/m^2$ and high-dose as doses $\geqq\;1000\;mg/m^2$. Leucovorin should be administered to minimize MTX toxicities when MTX doses are greater than $80-100\;mg/m^2$. The clinical pharmacokinetics (ADME) of MTX is discussed in this text.

• Korean Journal of Clinical Pharmacy
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• v.29 no.2
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• pp.101-108
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• 2019

Background: High doses of methotrexate (MTX) are often used in various chemotherapy protocols to treat acute lymphoblastic leukemia (ALL) and non-Hodgkin's lymphoma (NHL) in children, but its delayed elimination increases the occurrence of adverse events, such as bone marrow suppression. The aim of this study was to investigate the elimination of MTX at 24 and 48 hours. Methods: We retrospectively analyzed electronic medical records of ALL or NHL pediatric patients who received $5g/m^2$ MTX infusion over 24 hours (between June, 2012 and July, 2018) at the Yonsei University Health System, Korea. The delayed elimination of MTX concentrations was assessed with 100 or $150{\mu}M$ MTX at 24 hours, and 2 or $5{\mu}M$ at 48 hours. Results: Among the 85 MTX cycles administered, 23 cycles were classified in delayed elimination group, and 62 cycles showed normal elimination. At 24 hours, the delayed elimination group with MTX concentration > $100{\mu}M$ showed higher percentage than group with MTX concentration < $100{\mu}M$ (45.8% vs. 19.7%, p = 0.015). However, no differences were observed at $150{\mu}M$ MTX (p = 0.66). At 48 hours, the delayed elimination was higher than the normal elimination at both concentration baselines (p < 0.001 at $2{\mu}M$, p = 0.024 at $5{\mu}M$). Conclusions: MTX concentrations greater than $100{\mu}M$ show high probability of delayed elimination at 24 hours. When MTX levels are above normal, leucovorin and hydration regimens should be continued to prevent delayed elimination.

• Journal of Yeungnam Medical Science
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• v.16 no.1
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• pp.131-136
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• 1999

자궁경관 임신은 최근에 인공유산의 증가와 인공 보조 생식술(assisted reproductive technology) 등에 의하여 증가되는 양상을 보인다. 과거에는 자궁경관 임신은 대량의 무통성 질출혈로 진단을 내리고 치료 방법은 천자궁적출술이 유일한 수단이었으나, 지금은 질식 초음파의 개발로 자궁경관 임신을 조기에 진단하고 자궁 보존적 방법으로 치료하여 차후 임신을 기대할 수 있게 되었다. 그 치료 방법 중 하나로 Methotrexate(MTX)를 주사하여 성공적으로 치유된 많은 보고들이 있었다. 본 저자들은 임신 8주에 자궁경관 임신으로 진단된 환자에서 전신적 MTX 투여와 복식 초음파 관찰 하에 양막강내 MTX 투여 병합 요법으로 치료한 1례를 보고하고 치료과정에서 자궁경부 병변의 지연 관해에 대해서 문헌 고찰과 함께 보고하는 바이다.

• Archives of Pharmacal Research
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• v.12 no.3
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• pp.186-190
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• 1989

The release rates of methotrexate (MTX) from MTX-human serum albumin (HSA) conjugate, and 5-fluorouracil (5-FU) from 5-FU acetic acid (AA)-HSA conjugate were determined after incubation of the conjugates in various conditions. The concentrations of 5-FU released from the conjugate increased monoexponentially, however those of MTX increased biexponentially in all studies. It indicated that there are two distinct types of MTX-HSA linkage, weakly and tightly bound linkages. The release rates of 5-FU were lower than those of MTX in all studies indicating that the bond of 5-FU-AA-HSA conjugate is very stable, which is supported by the higher value of activation energy (39. 9 vs 10. 7 Kcal/mole) using Arrhenius equation. The release rates of MTX and 5 -FU from the conjugates increased with incubation temperatures. Proteolytic enzyme and liver homogenates accelerated significantly the release rates of MTX and 5-FU. Approximately 1.30 and 22.0% of MTX were released after 12 hours of incubation in the absence and presence of protease, respectively. The corresponding values for 5-FU were released after 12 hours of incubation with rat liver homogenates which were diluted 6 times with phosphate buffer of pH 6.0. The MTX-HSA and 5-FU-AA-HSA conjugates were very stable in rat plasma.

• Journal of Life Science
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• v.16 no.2 s.75
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• pp.259-265
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• 2006

This study is investigated the effect on mechanism of nephrotoxicity formation of methotrexate(MTX) by hyperglycemic by streptozotocin(STZ). MTX was injected daily at two doses of 3, 6 mg/kg for 1 week in STZ-induced hyperglycemic rats. Activities of BUN, creatinine and LDH were significantly increased by treatment with MTX in STZ-induced diabetic group when compared to MTX treatment group in normal rats' Renal lipid peroxide content and activities of cytosolic enzyme were significantly increased in the treatment of MTX in diabetic group. The concentration of glutathione and glutathione biosynthesis enzymes were decreased by treatment with MTX in STZ-induced diabetic group. These results suggest that nephrotoxicity of MTX in STZ-induced hyperglycemic rat was caused by activation of renal metabolizing enzymes in cytosol and decrease of glutathione concentration.

• Journal of Pharmaceutical Investigation
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• v.26 no.2
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• pp.105-112
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• 1996

The surface of albumin microspheres was modified with methotrexate(MTX) by using 1,3-dicyclohexylcarbodiimide (DCC). Surface-modified albumin microspheres entrapping no MTX (SAMS), free MTX (SAMSF) and MTX-bovine serum albumin(BSA) conjugates(SAMSC) were prepared. The organ-targeting ability of free $[^3H]MTX,\;[^3H]MTX-BSA$ conjugate and the above microspheres was evaluated after i.v. administration of the preparations, equivalent to 150 nCi via the tail vein of mice. The total radioactivity in the lung increased immediately in a few minutes after i.v. injection of the microspheres, and then declined for the period of 3-4 weeks. However, the radioactivity in the liver, spleen and kidney increased slowly during the rapid decrease in radioactivity in the lung. This suggested that the microspheres could be entrapped rapidly in the lung through mechanical filtration because of their large size and slowly redistributed to the liver, spleen and kidney due to either the microspheres being degraded enough for the size to allow passage through the capillary beds of the lung and/or the release of $[^3H]MTX\;or\;[^3H]MTX-BSA$ conjugates from the microspheres. The amount of $60{sim}70%$ of the dose was targeted to the liver after the i.v. injection of SAMS, SAMSF and SAMSC, and the values of $(R_e\;^*\;_{e)liver}$ from the microspheres were $5{\sim}7$ compared to free MTX. This suggested that the liver-targeting ability from surface-modified albumin microspheres could be $5{\sim}7$ times as that of free MTX. The liver-targeted drug was accumulated in the Kupffer cells at the initial stage, thereafter the drug in the Kupffer cell was slowly transferred into the hepatocytes. The value of AUQ for liver from SAMS was higher than that from SAMSF, but much lower than that from SAMSC. This suggest that MTX bound to their surface could be eliminated slower than the entrapped free MTX, and faster than the entrapped MTX-BSA conjugates. This is consistent with the in vitro release rates order in the presence of a proteolytic enzyme. Also, surface-modified MTX was scarcely released in the absence of a proteolytic enzyme. Therefore, the surface-modified MTX nay be released (or eliminated) rapidly from SAMSC at the target site, and thereafter MTX may be released (or eliminated) slowly from the entrapped MTX-BSA conjugates in SAMSC for a long period.