• Korean Journal of Clinical Pharmacy
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• v.7 no.2
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• pp.51-63
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• 1997

The effect of cimetidine administration on the pharmacokinetic parameters of cyclosporine were determined in healthy voluteers. This study was performed in 10 volunteers of age ranged 22-48 years and body weight 48-62 kg. This study was performed with cross-over design. Mono cyclosporine and cyclosporine metabolites was extracted from whole blood analysed by fluororescence polarization immune assay (TDX-FLX, Abbott). After coadministration of cimetidine (300 mg) with cyclosporine (300 mg) orally, maximum concentration of mono cyclosporine was significantly increased $1221{\pm}143\;ng/ml\;to\;1562{\pm}184\;ng/ml$ (P<0.05), area under the time curve of cyclosporine (12 hr) also was significantly increased $7478{\pm}829\;ng/ml{\cdot}hr\;to\;9721{\pm}879\;ng/ml{\cdot}hr$ (P<0.05) and absolute baioavailability of cyclosporine was increased $50\pm5.6\%\;to\;57.6\pm6.1\%\;(P<0.05)$ compared to control group. The blood concentrations of cyclopsorine metabolites were significantly decrased (P<0.05) after coadministration of cimetidine. In cimetidine pretreated group, blood mono cyclosporine concentrations were increased significan시y $1220.0\pm203.00\;ng/ml\;to\;1510.0\pm204.00\;ng/ml$ compared with control group (P<0.05). In the mono cyclosporine pharmacokinetic parameter after oral administration absorption rate and maximum concentration were significantly higher in cimetidine coadministered and pretreated group than control group (P<0.05). The ratio of metabolites and mono cyclosporine concentrations was decreased significantly from $70.8\%\;in\;control\;to\;34.8\%$ in coadministration of cimetidine orally. As matter of facts these reults are considered to inhibition of cyclosporine hepatic metabolism and increasing of cyclosporine absorption rate in gastrointestinal tract because of maintaining cyclosporine stability in elevated gastric pH by cimetidine. We considered, it appeares that cimetidine increase bioavailability of cyclosporine by increasing oral absorption and by decreasing hepatic clearance. But the absorption and clearance of cyclosporine was highly variable individually, and therefore we consider that cyclosporine blood level monitoring would be essential in patients with cimetidine co-administration.

• The Korean Journal of Physiology and Pharmacology
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• v.3 no.6
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• pp.631-640
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• 1999

The present study investigated the stimulatory effects of iron (or ascorbate) on cyclosporine-induced kidney mitochondrial damage. Damaging effect of $50\;{\mu}M$ cyclosporine plus $20\;{\mu}M\;Fe^{2+}$ on mitochondrial lipids and proteins of rat kidney and hyaluronic acid was greater than the summation of oxidizing action of each compound alone, except sulfhydryl oxidation. Cyclosporine and $100\;{\mu}M$ ascorbate showed an enhanced damaging effect on lipids but not on proteins. The peroxidative action of cyclosporine on lipids was enhanced with increasing concentrations of $Fe^{2+}.$ Ferric ion $(20\;{\mu}M)$ also interacted with cyclosporine to stimulate lipid peroxidation. Damaging action of cyclosporine on mitochondrial lipids was enhanced by ascorbate $(100\;{\mu}M\;and\;1\;mM)$. Iron chelators, DTPA and EDTA, attenuated carbonyl formation induced by cyclosporine plus ascorbate. Cyclosporine $(100\;{\mu}M)$ and $50\;{\mu}M\;Fe^{2+}$ $(or\;100\;{\mu}M\;ascorbate)$ synergistically stimulated degradation of $2-{\alpha}$ deoxyribose. Cyclosporine $(1\;to\;100\;{\mu}M)$ reduced ferric ion in a dose dependent manner, which is much less than ascorbate action. Addition of $Fe^{2+}$ caused a change in absorbance spectrum of cyclosporine in $230{\sim}350$ nm of wavelengths. The results show that cyclosporine plus iron (or ascorbate) exerts an enhanced damaging effect on kidney mitochondria. Iron and ascorbate appear to promote the nephrotoxicity induced by cyclosporine.

• Childhood Kidney Diseases
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• v.2 no.1
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• pp.20-25
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• 1998

Purpose : It has been reported that endothelin-1 can be associated with the development of cyclosporine A nephrotoxicity. Levels of endothelin-1 was assayed to determine the effect of cyclosporine A on the plasma and urine levels of this peptide. Method : Nine patients who were less than 15 years of age and were also diagnosed as steroid dependent minimal change nephrotic syndrome were included in this study. Assay of endothelin-1 was done before and 3 months after cyclosporine A treatment. The mean age of the patients was $8.3{\pm}4.6$ years. Result : There was no significant differences in the plasma levels of endothelin-1 before and after 3 months of cyclosporine A treatment ($3.22{\pm}0.39$ pg/mL vs. $3.84{\pm}1.52$ pg/mL, P=0.64). Also there was no changes in the urine levels of endothelin-1 ($21.8{\pm}5.8$ pg/mL vs. $20.3{\pm}3.1$ pg/mL, P=0.30). Conclusion : No significant changes of endothelin-1 levels were found with 3 months of cyclosporine A treatment. Further studies with longer durations will help clarifying the effect.

• Clinical and Experimental Pediatrics
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• v.51 no.3
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• pp.293-298
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• 2008

Purpose : The aim of our study was to evaluate the therapeutic response to cyclosporine, time to remission and side effects in steroid resistant nephrotic syndrome (SRNS). Methods : This study included 22 children with idiopathic SRNS who were treated with cyclosporine between June 1989 and August 2006. Medical records were reviewed retrospectively. Results : The mean age of patients at diagnosis was $5.2{\pm}3.3\;years$. The male to female ratio was 1.2:1. Pre-treatment renal biopsies showed minimal change (MCD) in 12 (54.5%), focal segmental glomerulosclerosis (FSGS) in 8 (36.4%), membranous nephropathy (MGN) in one (4.5%) and mesangioproliferative glomerulonephritis in one (4.5%). 15 (68.2%) patients responded to cyclosporine, of whom 11 (91.6%) patients were MCD, 3 (37.5%) patients FSGS, and 1 patient MGN (MCD vs FSGS, P<0.05). The time to remission in patients who responded to cyclosporine was $31.5{\pm}15.2\;days$. Four of the 15 cyclosporine responders maintained complete remission even after cessation of the medication Seven still received cyclosporine, 2 were intermittently treated with steroids after discontinuation of cyclosporine, and two were treated with cyclosporine and steroids. The mean duration of cyclosporine therapy was $546.5{\pm}346.2$, $1,392.9{\pm}439.7$, $439.5{\pm}84.1$, and $433.5{\pm}74.2$ days, respectively. We performed post-treatment biopsies in 8 patients and partial interstitial fibrosis and tubular atrophy were found in two. Conclusion : The thrapeutic response of cyclosporine is good in steroid resistant nephrotic syndrome, especially in minimal change. But, there is a problem of long term cyclosporine dependency.

• Childhood Kidney Diseases
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• v.1 no.2
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• pp.179-182
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• 1997

Cyclosporine is an immunosuppressant usually used to prevent renal transplantation rejection. Nephrotoxicity and hypertension are considered as the most frequent side effects of cyclosporine treatment. The neurotoxic effects of cyclosporine such as agitation, anxiety, delirium, depression and psychosis have recently been found. Methylprednisolone may increase as well plasma concentration of cyclosporine, which leads to side effects. Here we report a $Henoch-Sch\"{o}nlein$ nephritis patient treated with cyclosporine and methylprednisolone who has experienced psychosis including visual and auditory hallucination and convulsion.

• YAKHAK HOEJI
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• v.46 no.4
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• pp.265-269
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• 2002

The purpose of this study was to report the pharmacokinetic changes of cyclosporine after oral administration of cyclosporine, 10 mg/kg, in rabbits coadministered or pretreated twice per day for 3 days with nimodipine, dose of 5 mg/kg. The area under the plasma concentration-time curve (AUC) of cyclosporine was significantly higher in rabbits pretreated with nimodipine than that in control rabbits (p＜0.01), showing about 149％ increased relative bioavailability. The peak plasma concentration (C$_{max}$), elimination half-life (t$_{1}$2/) and MRT of cyclosporine were increased significantly (p＜0.05) in rabbits pretreated with nimodipine compared with those in control rabbits. This findings could be due to significant reduction of elimination rate constant and total body clearance by pretreated with nimodipine. The effects of nimodipine on the pharmacokinetics of oral cyclosporine were more considerable in rabbits pretreated with nimodipine compared with those in control rabbits. The results suggest that the dosage of cyclosporine should be adjusted when the drug would be coadministered chronically with nimodipine in a clinical situation.n.

• Korean Journal of Clinical Pharmacy
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• v.10 no.1
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• pp.19-24
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• 2000

The effect of cimetidine on the pbarmacokinetic parameters of cyclosporine (intravenous administration) were determined in 6 healthy volunteers (22-48 years old, 48-62 kg) by cross-over design. Cyclosporine and cyclosporine metabolites in whole blood were analysed by fluororescence polarization immunoassay (TDx-FLX). The blood concentrations of cyclosporine After pretreatment with cimetidine (200 mg bid, for 3days) were increased significantly at 8-12 hrs compared to the control (p<0.05). The ratios of blood concentrations of cyclosporine metabolites (M1, M17) to parent drug were decreased significantly at 8-12 hrs (p<0.05). Total body clearance (CL) was also decreased significantly (p<0.05), and area under the curve $(AUC,\%)$ was increased but not significant.

• Korean Journal of Clinical Pharmacy
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• v.9 no.1
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• pp.66-70
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• 1999

The effect of circadian rhythm on cyclosporine pharmacokinetics was studied in rabbits after oral administration of 10 mg/kg dose of cyclosporine at 10:00 a.m. and 10:00 p.m. The blood concentration data were subjected to simultaneous computer nonlinear least squares regression analysis using a 1-compartment pharmacokinetic model. The blood concentrations of cyclosporine at 10:00 a. m. were increased significantly during 2-6 hr compared to those at 10:00 p.m. The area under the blood concentration-time curve (AUC) and peak concentration $(C_{max})$ of cyclosporine at 10:00 a.m. were increased significantly compared to those at 10:00 p.m. The mean total body clearance (CL) of cyclosporine at 10:00 a.m. were decreased significantly compared to those at 10:00 p.m. It is reasonable to consider individual circadian rhythm for effective dosage regimen of cyclosporine in therapeutics.

• Korean Journal of Clinical Pharmacy
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• v.28 no.1
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• pp.24-29
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• 2018

Background: Cyclosporine is an immunosuppressive agent used to treat and prevent graft versus host reaction (GVHR)-a complication associated with stem cell transplantation. This study aimed to develop a population pharmacokinetic model of cyclosporine and investigate factors affecting cyclosporine clearance in pediatric hematopoietic stem cell transplant patients. Methods: A total of 650 cyclosporine concentrations recorded in 65 patients who underwent hematopoietic stem cell transplantation were used. Data including age, sex, weight, height, body surface area (BSA), type of disease, chemotherapy before stem cell transplantation, type of donor, serum creatinine levels, total bilirubin concentration, hematocrit value, and type of concomitant anti-fungal agents and methylprednisolone used were retrospectively collected. Data related to cyclosporine dosage, administration time, and blood concentration were also collected. All data were analyzed using the non-linear mixed effect model; a two-compartment model with first-order elimination was used. Results: The population pharmacokinetic model of cyclosporine using the NONMEM program was as follows: $CL(L/h)=5.9{\times}(BSA/1.2)^{0.9}$, V2 (L) = 54.5, Q (L/h) = 3.5, V3 (L) = 1080.0, $k_a(h^{-1})=0.000377$. BSA was selected as a covariate of cyclosporine clearance, which increased with an increase in BSA. Conclusion: A population pharmacokinetic model for Korean pediatric hematopoietic stem cell transplant patients was developed, and the important factor affecting cyclosporine clearance was found to be BSA. The model might contribute to the development of the most appropriate dosing regimen for cyclosporine. Further studies on population pharmacokinetics should be carried out, prospectively targeting pediatric patients.

• Journal of Periodontal and Implant Science
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• v.24 no.2
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• pp.238-254
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• 1994

Cyclosporine A is an immunosuppressant commonly used for patients receiving organ transplants. Gingival overgrowth is an adverse side-effect seen in about 8-26% of patients taking cyclosporine A which have been shown to increase the DNA synthesis of gingival fibroblast at the concentration of $10^{-9}g/ml$ in vitro. Glycyrrhetinic acid is the active pharmacological ingredients of licorice which exerts steroid-like action and anti-viral activity. Oleanolic acid, which were isolated from Glechoma hederacea, has been shown to act as inhibitors of tumor promotion in vivo and to be less cytotoxic retinoic acid. This study has been performed to evaluate the effects of glycyrrhetinic acid and oleanolic acid on cyclosporine A induced cell activity in vitro. Human gingival fibroblasts were isolated from explant cultures of healthy gingiva of orthodontic patients. Gingival fibroblasts were trypsinized and transferred to the walls of microtest plates. Fibroblasts were cultured in growth medium added $10^{-9}g/ml$ cyclosporineA and $50{\mu}l/ml$ lipopolysaccharides. Cells between the 4th and 6th transfer in culture were used for this study. The morphology of gingival fibroblst were examined by inverted microscope. The effects of cyclosporine A on the time course of DNA sythesis by human gingival fibroblasts were assessed by $[^3H]-thymidine$ uptake assays. Cyclosporine A was found to stimulate DNA synthesis of human gingival fibroblast at a concentration of $10^{-9}g/ml$. In the presence of lipopolysaccharide derived from Fusobacterium nucleatum, addition of cyclosporine A results in reversal of inhibition at the concentration which normally inhibits gingival fibroblast proliferation. The cell acitivities in the presence of glycyrrhetinic acid and oleanolic acid were decreased, and increased cell acitivities by cyclosporine A were decreased by glycyrrhetinic acid and oleanolic acid at the concentration of $200{\mu}g/ml$. These results suggested that the increased cell activities by cyclosporine A modulated by glycyrrhetinic acid and oleanolic acid.