• Journal of Marine Bioscience and Biotechnology
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• v.14 no.1
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• pp.33-42
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• 2022

Tacrolimus, a type of macrolide produced by Streptomyces tsukubaensis, is widely used as an immunosuppressant. However, continuous exposure to tacrolimus causes oxidative stress in normal cells, ultimately inducing cell injury. Therefore, this study investigated whether luthione, a reduced glutathione, could inhibit tacrolimus-induced cytotoxicity in olive flounder (hirame) natural embryo (HINAE) cells. According to the results, luthione significantly inhibited tacrolimus-induced reduction in cell viability in a concentration-dependent manner. Additinally, although luthione unaffected autophagy by tacrolimus, tacrolimus-induced apoptosis was significantly suppressed in the presence of luthione. Luthione also markedly blocked DNA damage in tacrolimus-treated HINAE cells, associated with the inhibition of reactive oxygen species (ROS) generation. Additionally, tacrolimus cytotoxicity in HINAE cells was correlated with increased inflammatory response, also attenuated by luthione. Collectively, these results show that at least luthione protects HINAE cells against tacrolimus-induced DNA damage, apoptosis, and inflammation, but not autophagy, by scavenging ROS. Although additional in-vivo studies are required, this study's results can be used as a basis for utilizing luthione to reduce the toxicity of fish cells caused by excessive immune responses.

• Bulletin of the Korean Chemical Society
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• v.32 no.1
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• pp.109-112
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• 2011

A new derivative of tacrolimus was evaluated for its molecular weight, using LC-MS of the tacrolimus bulk active pharmaceutical ingredient (API) recovered through the purification of crude tacrolimus produced by Streptomyces clavuligerus CKD-1119. In addition, the molecular weight of the new derivative of tacrolimus was found to be at m/z 818 and was identified by $^{13}C$-NMR with peak assignments based on the differences in methyl group location resulting from the chemical structure. The structure of the new derivative, an unknown impurity of tacrolimus, was found to be 18-methyltacrolimus through comparison of the spectral data of the structural differences between ascomycin, tacrolimus, and the new derivative 18-methyltacrolimus.

• Bulletin of the Korean Chemical Society
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• v.32 no.3
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• pp.956-960
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• 2011

The objective of this investigation was to develop nanostructured lipid carriers (NLCs) of tacrolimus by the hot homogenization technique by sonication. NLCs are commonly prepared by emulsification and lyophilization. The feasibility of fabricating tacrolimus-loaded NLCs was successfully demonstrated in this study. The developed NLCs were characterized in terms of their particle size, zeta potential, entrapment efficiency (EE) of tacrolimus, and morphology. Studies were conducted to evaluate the effectiveness of the NLCs in improving the penetration rate through hairless mouse skin. Tacrolimus-loaded NLCs were found to have an average size of $123.4{\pm}0.3\;nm$, a zeta potential of $-24.3{\pm}6.2\;mV$, and an EE of 50%. In vitro penetration tests revealed that the tacrolimus-loaded NLCs have a penetration rate that is 1.64 times that of the commercial tacrolimus ointment, Protopic$^{(R)}$.

• Molecules and Cells
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• v.28 no.2
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• pp.125-130
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• 2009

Tacrolimus is a widely used T cell targeted immunosuppressive drug, known as a calcineurin inhibitor. However, the exact pharmacological effects of tacrolimus on $CD4^+$ T cells have yet to be elucidated. This study investigated the effects of tacrolimus on $CD4^+$ T cell subsets. Mouse or human $CD4^+$ T cells were cultured with immobilized anti-CD3/CD28 antibodies in the presence of tacrolimus. The cell division of $CD4^+$ T cells was analyzed using a flow cytometer according to the expression of Foxp3. The gene expression patterns of tacrolimus-exposed T cells were examined by quantitative PCR. In the case of conventional $CD4^+$ T cells (Tconv cells), tacrolimus inhibited T cell receptor stimulation-induced cell division. In contrast, the cell division of regulatory $CD4^+$ T cells (Treg cells) was even promoted in the presence of tacrolimus, especially in humans. Tacrolimus did not promote conversion of Tconv to Treg cells in mice. Furthermore, tacrolimus modified the expression levels of Foxp3-regulated T cell receptor signal related-genes, PTPN22 and Itk, in human Treg cells. Immunosuppressive effect of tacrolimus may be attributed to the relatively enhanced proliferation of Treg cells in association with altered gene expression levels of TCR signaling molecules.

• Korean Journal of Clinical Pharmacy
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• v.26 no.4
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• pp.306-311
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• 2016

Objective: This study was performed to compare the changes in the blood concentrations of tacrolimus when either itraconazole or voriconazole is together with tacrolimus to prevent or treat invasive aspergillus pneumonia (IAP) in patients with lung transplants. Therefore we can compare the degree of drug-drug interactions between tacrolimus and itraconazole against tacrolimus and voriconazole. Methods: Patients who were admitted and had lung transplants in a territory referral hospital from September 2012 to May 2015 were analyzed retrospectively. The effects of itraconazole and voriconazole on the plasma concentrations of tacrolimus were analyzed. Results: Mean tacrolimus concentrations was $10.49{\pm}2.35ng/mL$ vs. $10.95{\pm}2.98ng/mL$ (p=0.722), and mean concentration of tacrolimus over the dose of tacrolimus per day was $8.510{\pm}5.890(ng/mL)/(mg/d)$ vs. $15.45{\pm}28.47(ng/mL)/(mg/d)$ (p=0.947) in itraconazole vs. voriconazole group each. The ratio of the number of the results out of target tacrolimus concentrations to the total number of tacrolimus concentration results was $18.0{\pm}13.3%$ vs. $24.4{\pm}18.5%$ (p=0.185). Conclusion: There were no significant differences between itraconzaole and voriconazole to have influences on mean concentrations of tacrolimus over tacrolimus dose per weight per day. However voriconazole tended to raise tacrolimus plasma concentrations more than itraconazole. Safer and more effective drug management to prevent and treat fungal infections should be done by therapeutic drug monitoring not only of tacrolimus but of itraconazole and voriconazole in lung transplant patients.

• Archives of Pharmacal Research
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• v.27 no.8
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• pp.878-883
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• 2004

Tacrolimus (FK506), which is isolated from Streptomyces tsukubaensis, is a new potent immu-nosuppressant. Because of poor solubility in water, the conventional intravenous dosage forms of tacrolimus contain surfactants such as cremophor EL (BASF Wyandotte Co.) or hydroge-nated polyoxy 60 castor oil (HCO-60) which may cause adverse effects. This study relates to a polymer-tacrolimus conjugate, which can be dissolved in water, formed by chemically binding the sparingly soluble drug, tacrolimus, with the water soluble polymer, methoxypoly(ethylene glycol) (mPEG). Water soluble tacrolimus-mPEG conjugates have been synthesized and shown to be function in vitro as prodrugs. These conjugates are in the form of an ester wherein the 24-, 32- or 24,32-positions are esterified. The desired 24-, 32- or 24,32-esterified com-pounds were obtained by initially acylating of tacrolimus with iodoacetic acid at the 24-,32-, or 24,32-positions and then reacting the resulting acylated tacrolimus with a mPEG in the pres-ence of a base such as sodium bicarbonate. These conjugates were converted again into tac-rolimus by the action of enzymes in human liver homogenate, and the half-lives of the conjugates are approximately 10 min in the homogenate, indicating that the esterified tacroli-mus derivatives may be practically applicable as a prod rug for the immunosuppressant.

• Korean Journal of Clinical Pharmacy
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• v.20 no.3
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• pp.193-199
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• 2010

Tacrolimus, an immunosuppressant prescribed against graft-versus-host disease (GVHD) in patients with allogeneichematopoietic stem cell transplantation (HSCT), is affected to change its pharmacokinetic properties by various factors. For this reason, it is needed a close monitoring to adjust dosage amount in order to optimize the blood concentration of tacrolimus is located within the effective range. According to our in-house study, 62% of HSCT-patients were needed dosage-adjustment and it is necessary to optimize the current immunosuppressive regimen in clinical settings. A retrospective study was designed to evaluate the dosing regimen (converting ratio of IV:PO=1:4) of tacrolimus in HSCT patients (n=62). After collecting data from patient's profile and medical record, pharmacokinetic parameters were calculate and compared between the estimated and the actual values in the selected subjects (n=58). It was found that the bioavailabilty (BA) of oral tacrolimus was 40.5% very much different from that is known as 25%. It implies that the current protocol has a potent risk causes dose-related toxicities to the patients. Furthermore, analyses among factors demonstrated that there was no statistical significance between BA of tacrolimus and the variable factors. In the clinical perspectives, the current converting ratio of tacrolimus in patients with HSCT to be re-considered and an appropriate and optimal alternative regimen should be adopted to prevent GVHD and to increase the quality of life of patients.

• Korean Journal of Clinical Pharmacy
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• v.32 no.4
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• pp.352-361
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• 2022

Objective: This study aimed to analyze the important medical adverse events (IMEs) of cyclosporine and tacrolimus using the reports in US FDA adverse event reporting system (FAERS) and to detect related signals. Methods: The FAERS database was used to analyze the IMEs reported for cyclosporine or tacrolimus during 2017-2021. Reporting odds ratio (ROR) and information component were used to analyze signals for adverse events of both drugs. It was investigated whether the detected signals were present on drug labels in Korea and the United States. Results: Among the total 24,688 reports, the reports on tacrolimus accounted 75.8%. Mean age of the patients was 47.9 years old and median number of adverse events was 2.0 per report. The number of patients hospitalized for adverse events was 7,979 (25.3%). Among the adverse reactions reported on the cyclosporine and tacrolimus, 576 and 1,363 events were detected as signals for cyclosporine and tacrolimus, respectively, and of these, IMEs accounted for 44.8 and 59.2%, respectively. The IMEs related with infections/infestations, renal/urinary disorders, and blood and lymphatic system disorders were reported frequently for both drugs. The most frequently detected IMEs were renal impairment for cyclosporine and acute kidney injury for tacrolimus. Among the top 3 IMEs for each reported SOC for cyclosporine and tacrolimus, 9 and 2 unexpected adverse events were identified, respectively. Conclusion: This study identified the IMEs and signals of cyclosporine and tacrolimus, and detected unidentified adverse events in a drug information database.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.8 no.1
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• pp.70-75
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• 2005

Crohn's disease of the perineum is notably resistant to treatment. We describe our experiences of tacrolimus ointment application in three patients with intractable perianal Crohn's disease. At the time of diagnosis patients showed anal fissure with ulcer, anal fistula, or perianal abscess, respectively. These lesions did not respond to steroid, metronidazole, mesalazine, or azathioprine, though the pediatric Crohn's disease activity index was markedly improved during the treatment period (4 to 12 months). Topical tacrolimus was applied and resulted in marked healing and a rapid granulation of cavity edges within 6 weeks to 3 months. Topical tacrolimus at a low dose shows a promise for the management of childhood perianal Crohn's disease. Further controlled studies are required to assess the efficacy and safety of this treatment.

• Korean Journal of Clinical Pharmacy
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• v.18 no.1
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• pp.60-67
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• 2008

This study aimed to compare a microparticle enzyme immunoassay (MEIA) with a liquid chromatography-tandem mass spectrometry (LC/MS/MS) technique for the measurement of tacrolimus concentrations in adult liver transplant recipients, to investigate how the assay choice influenced the population pharmacokinetics of tacrolimus and to identify patient characteristics that affected pharmacokinetic parameters in each assay. Tacrolimus concentrations from 29 liver (n=52 paired-samples) transplant recipients measured by both MEIA and LC/MS/MS were used to evaluate the performance of these methods in the clinical setting. Tacrolimus pharmacokinetics was studied independently using MEIA and LC/MS/MS data in 70 adult patients using a population approach performed with NONMEM. Patient characteristics which influenced pharmacokinetic parameters in each assay were compared. The relation between LC/MS/MS and MEIA measurements was best described by the regression equation MEIA=1.465*LC/MS/MS-1.336 (r=0.91). Multiple linear regression analysis showed significant inverse relationships between assay difference and hematocrit (Hct) (p<0.025) in liver graft recipients. In MEIA, the population estimate of tacrolimus CL/F and apparent volume of distribution (Vd/F) were found to be 10.1 L/h and 226 L, and in LC/MS/MS, 13 L/h and 305 L respectively. Neither patient's age, weight, gender, grafted hepatic weight, albumin concentration, nor markers of liver function influenced tacrolimus CL/F The final model of CL/F was found to be 10.1+(Hct/Hct mean)$^{12.0}$ in MEIA and 13+(1+Hct/578) in LC/MS/MS indicating that CL/F was influenced by hematocrit.