Bioavailability Of Cyclosporine Research Articles

The Pharmacokinetic and Absolute Bioavailability of Cyclosporine (Atopica for Cats®) in Cats.

This study aimed to evaluate the absolute bioavailability of cyclosporine in cats by investigating the pharmacokinetic profile after intravenous and oral administration, respectively. Twenty-four clinically healthy cats were enrolled in this study and randomly divided into four groups, namely the intravenous group (3 mg/kg), low oral group (3.5 mg/kg), medium oral group (7 mg/kg), and high oral group (14 mg/kg). Whole blood was obtained at the scheduled time points after a single dose administration and cyclosporine was determined using ultra-performance liquid chromatography-tandem mass spectrometry technology (UPLC-MS/MS). Pharmacokinetic parameters were calculated using the WinNonlin 8.3.4 software via compartmental and non-compartmental models. As a result, the bioavailability values for the low, medium, and high oral groups were 14.64%, 36.98%, and 13.53%, respectively. The nonlinear pharmacokinetic profile was observed in the range from 3.5 mg/kg to 14 mg/kg in cats following oral administration. Whole blood concentrations taken 4 h after oral administration were better correlated with the area under the blood concentration-time curve AUC0-24 with a high regression coefficient (R2 = 0.896). This concentration would be a greater predictor in the following therapeutic drug monitoring. No adverse effect was observed in the whole study process.

The Role of Stem Cells Derived From the Mesenchyme of the Umbilical Cord in Reducing Immunosuppressive Drug Doses Used in Allogenic Transplantations.

This study evaluated the potential of Wharton's jelly mesenchymal stem cells with high tolerogenic properties in reducing immunosuppressive dosage and related adverse effects. A 4- to 6-week-old, 30-40 g weight, male inbred CD57BL/6 mice were used as skin allograft donors, whereas Balb/c mice with similar characteristics were used as recipients. Wharton's jelly stem cells were obtained from a commercial kit sourced from human umbilical cord. Skin allografts were performed from CD57Bl6 to Balb/c mice (day 0). Group 1 (control) received no treatment. Group 2 received 15 mg/kg cyclosporin A on days 0 to 30. Group 3 received 5.7 × 10 6 and 10.3 × 10 6 cell/kg Wharton's jelly stem cells on days 0 and 3, respectively. Groups 4, 5, and 6 received a combination of 15, 10, and 5 mg/kg per day cyclosporine A (days 0 to 30) with the same stem cell dose with group 3, respectively. Graft rejection was evaluated with digital photography and thermal imaging, histopathology (Banff grading, epithelialization scores, dermoepidermal dissociation), immunochemistry (Ki-67 and Bcl-2), and biochemical methods (interleukin 10, interleukin 2, interferon γ, tumor necrosis factor α) (day 10). Cumulative adverse effects of cyclosporin A occurring in the groups were revealed by histopathological evaluation of kidney and liver (a modified semiquantitative method of infiltration of inflammatory cells around the portal area and lobular region in liver; modification of the Banff rating of proximal tubules and hypertrophia of juxtaglomerular apparatus cells in kidney) (day 30). There was no rejection in groups 2, 4, and 5 until the end of study. These were statistically different versus groups 1 (day 10 ± 0.71), 3 (day 11 ± 0.82), and 6 (day 11 ± 0.58) (all P 's < 0.05). Groups 4 and 5 have exhibited statistically similar findings in histopathological (4 epithelization score: 3.7 ± 1.3; 5 epithelization score: 3.5 ± 0.5; 4 Banff grading score: 0.8 ± 0.6; 5 Banff grading score: 1.0 ± 0.5; both P 's = 1.00), immunohistochemical (4 Bcl-2 score: 3.5 ± 0.5, P = 0.618; 5 Bcl-2 score: 3.4 ± 0.5, P = 1.00; 4 Ki-67 score: 3.7 ± 0.4, P = 1.00; 5 Ki-67 score: 3.5 ± 0.5, both P 's = 1.00), and levels of cytokines (both P 's = 1.00) versus group 2. Adverse effects on kidneys and liver were lowest and statistically similar in groups 3, 5, and 6 (all P 's = 00) versus group 1. Wharton's jelly mesenchymal stem cells alter bioavailability of cyclosporine, albeit at much lower doses and with fewer systemic adverse effects.

Pomegranate Juice does not Affect the Bioavailability of Cyclosporine in Healthy Thai Volunteers.

BackgroundIt is still controversial whether pomegranate causes drug interactions. Pomegranate juice has been shown to inhibit CYP3A in-vitro and animal studies. The co-administration of pomegranate juice with cyclosporine, a narrow therapeutic drug that is the substrate of CYP3A, might lead to drug toxicity. The objective of this study is to investigate the effect of pomegranate juice on the pharmacokinetics of cyclosporine in healthy Thai volunteers.MethodsThe study design was an open-label, randomized, single dose, crossover study with a 2-week washout period. Each fasting subject received 2 microemulsion tablets of 100 mg of cyclosporine with 500 ml of pomegranate juice (test) or 500 ml of water (control). Serial blood samples were collected up to 24 h after dosing, and blood samples were analyzed for cyclosporine concentrations by using chemiluminescent microparticle immunoassay. Fourteen healthy volunteers completed the study.ResultsThe 90% confidence intervals for the test/control ratio using logarithmically transformed data of area under the concentration-time curve (AUC) from time zero until the last measured concentration (AUC0-t), AUC from time zero to infinity (AUC0-∞), and maximum concentration (Cmax) were 91.6-105.6, 92.0-105.2 and 82.3-102.5, respectively. The results were within the accepted bioequivalence range for narrow therapeutic index drugs (90-111% for AUC and 80-125% for Cmax). There were no differences in adverse event between the groups.ConclusionSingle dose administration of pomegranate juice with cyclosporine did not significantly affect the oral bioavailability of cyclosporine. However, further work is needed to thoroughly evaluate the effect of pomegranate on narrow therapeutic drugs.

Effects of coadministrations of unripe fruits and ripe peels of citrus aurantium on cyclosporine pharmacokinetics in rats

The unripe fruits (UF) and ripe peels (RP) of Citrus aurantium are two widely used Chinese herbs. Cyclosporine, an important immunosuppressant with narrow therapeutic window, is clinically subject to relevant interaction with Citrus herbs as with grapefruit juice. This study investigated the effects of coadministration of UF and RP on cyclosporine pharmacokinetics in rats. Sprague-Dawley rats received cyclosporine (2.5 mg/kg) orally with and without the UF and RP decoctions individually. Blood samples taken via cardiopuncture were assayed for cyclosporine by a specific monoclonal fluorescence polarization immunoassay. After coadministration orally with UF decoction, the Cmax and AUC0-t of cyclosporine were significantly decreased by 72.8% and 55.6%, respectively. However, when RP was coadministered orally, no conspicuous alteration of cyclosporine pharmacokinetics was observed. It can be concluded that UF, but not RP decoction, significantly decreased the bioavailability of oral cyclosporine. We suggest that coadministration of Citrus herbs with cyclosporine is better avoided to ensure the efficacy and safety of cyclosporin medication.

Marked decrease of cyclosporin absorption caused by coadministration of Cordyceps sinensis in rats

Cordyceps (Cordyceps sinensis Saccardo.) is a popular traditional tonic used in Taiwan and mainland China. Cyclosporin is an important immunosuppressant with narrow therapeutic index. This study investigated the effect of coadministration of cordyceps on cyclosporin pharmacokinetics in rats. Cyclosporin was intravenously (0.8 mg/kg) and orally (2.5 mg/kg) administered with and without cordyceps (2.0 g/kg), respectively, in crossover designs. Blood samples were collected by cardiopuncture and quantitated by a specific monoclonal fluorescence polarization immunoassay. Pharmacokinetic parameters of cyclosporin were calculated using noncompartment model. Paired Student's t-test was used for statistical comparison. Our results indicated that oral coadministration of cordyceps significantly decreased the Cmax and AUC0-540 of cyclosporin by 85.5% and 83.2%, respectively. In addition, when rats were given cordyceps 1 hr before cyclosporin dosing, the Cmax and AUC0-540 of cyclosporin were significantly decreased by 85.9% and 84.4%, respectively. By contrast, when cyclosporin was given as an intravenous bolus, the disposition of cyclosporin was not altered by cordyceps, indicating that the interaction between oral cyclosporin and cordyceps occurred during the absorption phase. In conclusion, cordyceps markedly decreased the oral bioavailability of cyclosporin. Patients treated with cyclosporin are suggested to avoid the concurrent use of cordyceps for efficacy and safety.

Possible Role of P-Glycoprotein in Cyclosporine -Acitretin Drug Interaction

P-glycoprotein, an efflux transporter prevents intracellular accumulation of xenobiotics. Cyclosporine A and acitretin are used to treat psoriasis. The present research work aims to investigate the possible role of P-glycoprotein in Cyclosporine- Acitretin drug interaction due to evidence of both drugs having affinity for P-glycoprotein.The study has three different objective namely to assess apparent permeability coefficient of cyclosporine in presence of acitretin by non-everted sac technique, to study the intestinal permeation and absorption kinetics of cyclosporine in presence of acitretin by single pass intestinal perfusion (SPIP) technique and to study the influence of acitretin on oral bioavailability of cyclosporine in Wistar rats.The result of ex vivo, in situ and in vivo study showed that cyclosporine level increased in a time dependent manner. As the dose of acitretin increases the cyclosporine concentration in all three methods tend to increase and was statistically significant. The improvement in absorption of cyclosporine may be due to the inhibition of P-glycoprotein transporter in the intestine by acitretin. Thus acitretin may enhance the oral pharmacokinetics of cyclosporine. Hence this combination may require close monitoring for better therapeutic outcome. Our study confirmed the inhibitory role of acitretin on P-glycoprotein leading to increase concentration of cyclosporine.

Interaction of Cyclosporine A with Pomegranate Juice and Its Potential Nephroprotective Effect in Rats

Objectives: To study the effect of concomitant administering of pomegranate juice orally (PJ) on bioavailability of cyclosporine A (CsA) and independently its potential nephroprotective effect against CsA induced nephrotoxicity.&#x0D; Methods: A- Pharmacokinetic study (PK), Wister rats were divided into groups (each 6 rats) I-: CsA PO + Vehicle; II- CsA IP + Vehicle, III- CsA PO + PJ, IV- CsA IP + PJ. CsA dose was 20 mg/kg for 5 days the vehicle or PJ (2 ml) was given 1 h before drug administration. Blood samples were taken at the 1st and 5th day at specified times and CsA level was determined by immune assays. Relative bioavailability of CsA was determined.&#x0D; B- Nephroprotection study (separate study to administer bioequivalent CsA PO doses, in view of PK study), I- ( CsA 13 mg PO + 2 ml PJ .II- CsA 20 mg P0 + 2 ml vehicle (for 28 day). The design also includes two control groups (vehicle alone or PJ alone). Blood samples for drug analysis, biochemical investigations and kidney samples for histopathology were taken at the 28th day.&#x0D; Results: PJ juice enhanced the bioavailability of oral CsA by about 50% (P &gt; 0.05). But CsA (IP) was not affected after repeated administration for 5 days. Independently, the marked kidney damage induced by CsA was reversed by concomitant administration of PJ as well as it attenuated the increase in serum creatinine.&#x0D; Conclusions: Repeated administration of pomegranate juice enhance CsA oral bioavailability which likely due to inhibition of intestinal enzymes and transport pump. Independently it caused significant attenuation of CsA induced renal toxicity.

Enhanced Dissolution and Oral Bioavailability of Cyclosporine A: Microspheres Based on αβ-Cyclodextrins Polymers.

Cyclosporine (CsA) has a selective property of suppressing various T-lymphocyte functions. This is of utmost importance in preventing allograft rejection by several organ transplantations, as well as in the treatment of systemic and local autoimmune disorders. However, the poor water solubility of CsA can be a major hurdle for its absorption into the blood stream, which leads to low bioavailability and thus less efficacy. The aim of this study was to prepare, characterize, and evaluate in vitro as well as in vivo, the potential of the innovative CsA drug delivery system. The latter contains CsA in spherical amorphous solid dispersion (SASD) which is embedded in an original α-cyclodextrin and β-cyclodextrin polymer mixture (Poly-αβ-CD) as a multifunctional amorphous carrier. The new developed SASD formulation showed that CsA was molecularly dispersed in αβ-cyclodextrins in an amorphous form, as was confirmed by physicochemical characterization studies. Interestingly, the peptide secondary structure, and thus, the drug activity was not impacted by the preparation of SASD as was shown by circular dichroism. Furthermore, the in vitro CsA release profile kinetics was almost identical to the commercially available product Neoral®. This study presents the first in vivo proof-of-concept for a novel drug delivery system based on Poly-αβ-CD containing CsA, with SASD allowing for increased bioavailibility. The pharmacokinetic parameters of cyclosporine A from the spherical spray-dried dispersion formulation was demonstrated in a “rat” animal model. For comparison, the commercially available Neoral® was studied. Importantly, the pharmacokinetic parameters were improved by extending Tmax from 2 to 3 h after the oral administration in rats, and eventually preventing the enterohepatic circulation. All these results clearly demonstrate the improved pharmacokinetic parameters and enhanced bioavailability of CsA in the new developed drug delivery system. These data demonstrated the superiority of the newly developed Poly-αβ-CD formulation for oral administration of the poorly soluble CsA in vivo without altering its secondary structure. Poly-αβ-CD can be a very useful tool for the oral administration of poorly water-soluble drugs.

Quercetin‑3‑O‑β‑D‑glucoside decreases the bioavailability of cyclosporin A through regulation of drug metabolizing enzymes, transporters and nuclear receptors in rats.

Quercetin is a flavonoid compound that is widely present in food and drink. Quercetin-3-O-β-D-glucoside (Q3GA) is a major metabolite of quercetin. The aim of the present study was to investigate the effect of Q3GA on the pharmacokinetics of orally and intravenously administered cyclosporin A (CsA) in rats, and to assess the effect of Q3GA on drug-metabolizing enzymes (DMEs), drug transporters (DTs) and nuclear receptors (NRs). The pharmacokinetic parameters of CsA were measured following oral (10 mg/kg) and intravenous (2.5 mg/kg) administration of CsA in the presence or absence of Q3GA. The mRNA and protein expression levels of DMEs, DTs and NRs in the liver and small intestine were detected by quantitative polymerase chain reaction and western blot analysis. The results indicated that the intravenous administration of Q3GA (2.5, 5 or 10 mg/kg) for 7 consecutive days reduced the bioavailability of oral CsA. By contrast, the pharmacokinetics of the intravenous administration of CsA were not affected by Q3GA. However, the mRNA and protein expression levels of DMEs and DTs were inhibited by Q3GA. The activation of DMEs and DTs by NRs, and the interplay between DMEs and DTs, may explain these results. The present study identified a novel flavonoid-drug interaction, which may have implications for patients taking CsA and quercetin supplements or on a quercetin-containing diet.

Enhanced digestion inhibition and mucus penetration of F127-modified self-nanoemulsions for improved oral delivery

Self-nanoemulsifying systems (SNEs) have excellent ability to improve the solubility of poorly water-soluble drugs (PWSD). However, SNEs are likely to be degraded in gastrointestinal (GIT) when their surface is recognized by lipase/co-lipase enzyme complex, resulting in rapid release and precipitation of encapsulated drugs. The precipitates are then captured and removed by intestinal mucus, reducing the delivery efficacy of SNEs. Herein, the amphiphilic polymer Pluronic® F127 was incorporated into long and short-chain triglycerides (LCT, SCT) based SNEs to diminish the recognition and therefore minimized their degradation by enzymes and clearance by mucus. The SNEs were characterized in terms of particle size, zeta potential and stability. Ex vivo multiple particles tracking studies were performed by adding particle solution into fresh rat mucus. Cellular uptake of SNEs were conducted by using E12 cells, the absorption and distribution in small intestine were also studied after oral administration in male Sprague-Dawley (SD) rats. The in vitro digestion rate of SNEs were found to be in following order SCT-SNE > SCT-F127-SNE > LCT-SNE > LCT-F127-SNE. Moreover, the LCT-F127-SNE was found to be most effective in enhancing cellular uptake, resulting in 3.5-fold, 2.1-fold and 1.7-fold higher than that of SCT-SNE, LCT-SNE and SCT-F127-SNE, respectively. After incubating the SNE with E12 cells, the LCT-F127-SNE exhibited the highest amount regarding both mucus penetration and cellular uptake, with an uptake amount number (via bicinchoninic acid (BCA) analysis) of 3.5-fold, 2.1-fold and 1.7-fold higher than that of SCT-SNE, LCT-SNE and SCT-F127-SNE, respectively. The in vivo results revealed that orally administered LCT-F127-SNE could significantly increase the bioavailability of Cyclosporine A (CsA), which was approximately 2.43-fold, 1.33-fold and 1.80-fold higher than that of SCT-SNE, SCT-F127-SNE and LCT-SNE, respectively. We address in this work that F127-modified SNEs have potentials to improve oral drug absorption by significantly reducing gastrointestinal enzymatic degradation and simultaneously enhancing mucus penetration.

Semifluorinated alkane based systems for enhanced corneal penetration of poorly soluble drugs

Semifluorinated alkanes (SFAs) are amphiphilic liquids that can dissolve hydrophobic drugs to form clear solutions. This study evaluated the potential of two SFAs to act as vehicle for topical ocular drug delivery. After confirming ocular safety, an ex vivo corneal penetration model was developed to determine drug distribution and corneal bioavailability. Hydrophobic dye distribution in the different corneal layers was visualised under a confocal microscope. Corneal bioavailability of cyclosporine A (CsA) dissolved in perfluorobutylpentane (F4H5) or perfluorohexyloctane (F6H8) was compared to commercially available CsA ophthalmic emulsions, Restasis® and Ikervis®. Precorneal residence of the four test vehicles containing the hydrophobic dye was also compared using an ex vivo corneal tissue model. Preferential accumulation of the hydrophobic dye in the corneal epithelium was observed with higher amounts detectable when delivered via the SFAs compared to Restasis or Ikervis. A significant improvement in corneal CsA penetration was observed after application of a single dose of 0.05% CsA in F4H5 and F6H8 when compared to Restasis with the area under curve over 4 h (AUC(0–4h)) being at least 8-fold greater for both SFAs (p < .0001). Moreover, the AUC(0–4h) of 0.1% CsA in F4H5 was almost 5-fold greater than Ikervis (p < .0001). Finally, the precorneal residence time of both SFA solutions was significantly longer than that of the commercial emulsions with the AUC(0–60min) being 2- to 11-fold greater. This study demonstrated that SFAs can significantly improve the local bioavailability of hydrophobic drugs by increasing corneal penetration as well as prolonging precorneal residence. They therefore offer a promising new platform for topical drug delivery to the eye.

Preparation and characterization of nanoparticles composed of methylated N-(4-N,N-dimethyl aminobenzyl) chitosan for oral delivery of cyclosporine A

Abstract Cyclosporine is considered a highly lypophilic compound meaning low bioavailability through oral administration. In this study, cyclosporine was entrapped in a novel aromatic, quaternized derivative of chitosan (i.e. methylated N-(4-N,N-dimethyl aminobenzyl) chitosan) in order to improve solubility and bioavailability. Methylated N-(4,N,N-dimethyl aminobenzyl) chitosan was synthesized by the Schiff base reaction method. Polymeric nanoparticles containing cyclosporine was prepared and the physico-chemical properties of prepared nanoparticles were determined. The nanoparticles were studied morphologically using transmission electron microscopy (TEM). Finally, the release of cyclosporine from nanoparticles was studied in vitro using simulated intestinal fluid adjusted to pH of 6.8. For the preparation of nanoparticles, different formulations were studied and it was found that proper nanoparticles were prepared in equal concentration (1 mg/mL) of polymer and sodium tri-poly phosphate (TPP). The size, zeta potential, PdI, EE% and LE% of the prepared nanoparticles were reported as 173±36 nm, 23.1±4.18 mV, 0.243±0.05, 97.1±4.38% and 3.2±0.21%, respectively. The TEM images of nanoparticles revealed spherical to sub-spherical nanoparticles with no sign of agglomeration. This study suggests that preparations of nanoparticles composed of methylated N-(4,N,N-dimethyl aminobenzyl) chitosan can be a good candidate for improving the oral bioavailability of cyclosporine.

Rhubarb decreased the systemic exposure of cyclosporine, a probe substrate of P-glycoprotein and CYP 3A

1. Rhubarb, rhizome of Rheum palmatum L. (RP), is an important herb in clinical Chinese medicine.2. Cyclosporine (CSP) is an immunosuppressant with narrow therapeutic window. The oral bioavailability of CSP was associated with P-glycoprotein (P-gp) and CYP 3A4. CSP was used as a probe substrate to investigate the in vivo modulation effects of RP on P-gp and CYP 3A.3. Rats were orally administered 2.5 mg/kg of CSP with and without 0.25 and 1.0 g/kg of RP. The blood CSP concentration was determined by a specific monoclonal fluorescence polarization immunoassay.4. Both dosages of RP significantly decreased the Cmax and AUC0–t of CSP in rats. Mechanism studies indicated that RP activated the functions of P-gp and CYP 3A.5. RP ingestion reduced the systemic exposure of CSP through activating P-gp and CYP 3A.

Development of self-micellizing solid dispersion system employing amphipathic copolymer for the improvement of dissolution and oral bioavailability of cyclosporine A

Development of self-micellizing solid dispersion system employing amphipathic copolymer for the improvement of dissolution and oral bioavailability of cyclosporine A

Molecular Biological Analysis of Factors Influencing Pharmacokinetics to Achieve Personalized Pharmacotherapy

Large individual variations in drug efficacy and safety could be explained in part by pharmacokinetics regulated by drug transporters and drug-metabolizing enzymes. However, expression and/or function of these proteins often fluctuate in pathological conditions, causing individual pharmacokinetic variability. To achieve a personalized pharmacotherapy after liver transplantation, our group has been investigating the pharmacokinetics of drugs and factors causing its variation based on molecular biological analysis using rats with liver ischemia-reperfusion (I/R) injury as a model for injuries immediately after liver transplantation. The first finding is that the oral bioavailability of cyclosporine A (CsA), which is an immunosuppressant, was decreased by increased first-pass metabolism due to elevated CYP3A and P-glycoprotein (P-gp) specifically in the upper small intestine after liver I/R. Expression of CYP3A in the small intestine was also elevated through transcriptional regulation by endogenous bile acids, whereas expression and function of intestinal P-gp were increased by post-transcriptional regulation via microRNA-145. Next, the pharmacokinetics of a cationic drug, cimetidine, which is eliminated from the kidney, and the expressional variation of drug transporters in the kidney after liver I/R were examined. Liver I/R decreased tubular secretion of cimetidine, mainly because of decreased expression of rat organic cation transporter 2 in the kidney. These findings provide useful information on the etiology of liver I/R injury and appropriate use of immunosuppressants and drugs eliminated from the kidney after liver transplantation.

Herb-drug interaction: The importance of communicating with primary care physicians.

Herb-drug interaction: The importance of communicating with primary care physicians.

Pomelo enhances cyclosporine bioavailability in healthy male thai volunteers

The aim of this study was to investigate the effect of pomelo pulp on the pharmacokinetics of cyclosporine in healthy male Thai volunteers. The study design was an open-label, randomized, single dose, crossover study with a 2-week washout period. A single oral dose of 2 × 100 mg cyclosporine was administered with 200 mL of water. Each subject received 250 g of pomelo pulp or 250 mL of water 1 hour before drug administration and once again 10 minutes following drug administration. Blood samples were collected over a 24 hour period. The point estimates (90% confidence intervals) of the test/control ratio using logarithmic transformed data for the area under the curve (AUC) for blood concentration from time 0 to infinity (AUC(0- ∞)) and the observed maximum concentration (C(max)) were 128.8% (120.6-137.6) and 136.1% (126.0-146.8), respectively. These 90% confidence intervals were higher than the accepted bioequivalence range defined by the European Medicines Agency guidelines for narrow therapeutic index drugs (90%-111% for AUC and 80%-125% for C(max)). However, the apparent terminal half-life (t(1/2)) was not significantly different. In conclusion, co-administration of cyclosporine and pomelo pulp increased the relative bioavailability of cyclosporine.

Reduced bioavailability of cyclosporine A in rats by mung bean seed coat extract

Mung bean seed coat (MBSC) is a healthcare product in Asian countries. The aim of this study was to investigate the effect of an MBSC ethanol extract on the bioavailability of cyclosporine A (CsA) in rats. Rats were orally dosed with CsA alone or in combination with MBSC ethanol extracts (500 mg/kg, p.o.). The blood levels of CsA were assayed by liquid chromatography with an electrospray ionization source and tandem mass spectrometry (LC-MS/MS). The everted rat intestinal sac technique was used to determine the influence of MBSC on the absorption of CsA. The results reveal that combined CsA intake with MBSC decreased the Cmax, AUC0-t, t1/2z and MRT0-t values of CsA by 24.96%, 47.28%, 34.73% and 23.58%, respectively (P&lt;0.05), and significantly raised the CL/F by 51.97% (P&lt;0.01). The in vitro results demonstrated that significantly less CsA was absorbed (P&lt;0.05). The overall results indicate that after being concomitantly ingested, MBSC reduced the bioavailability of CsA, at least partially, in the absorption phase.

Capsaicin pretreatment increased the bioavailability of cyclosporin in rats: Involvement of P-glycoprotein and CYP 3A inhibition

Capsaicin (CAP), the main ingredient responsible for the hot pungent taste of chilli peppers. This study investigated the effect of CAP on the pharmacokinetics of Cyclosporin A (CyA) in rats and the mechanism of this food-drug interaction. The results indicated that after 7 days of low or middle dose of CAP (0.3 or 1.0 mg/kg), the blood concentration of CyA was not significantly changed compared with that of vehicle-treated rats, whereas the blood concentration of CyA in high dose group (3.0 mg/kg) was significantly increased. The total clearance (CL/F) of CyA was decreased, and the bioavailability was significantly increased to about 1.44-fold of that in vehicle-treated rats after 7 days of high dose CAP treatment. At this time, the P-gp and CYP3A1/2 in the liver and intestine were decreased at both the mRNA and protein levels. These results demonstrated that chronic ingestion of high doses of CAP will increase the bioavailability of CyA to a significant extent in rats and the food-drug interaction between CAP and CyA appears to be due to modulation of P-gp and CYP3A gene expression by CAP, with differential dose-dependence.

Review article. Assessing clinical evidence of drug interactions between citrus juices and cyclosporine

Background: Previous studies have demonstrated that grapefruit juice increased the bioavailability of cyclosporine;however, the results from the literature are inconsistent. Other citrus fruits such as pomelo or orange juice had variable effects on the bioavailability of cyclosporine.Objective: To assess the effect of grapefruit juice and other types of citrus juice on oral bioavailability of cyclosporine in humans using meta-Analysis.Methods: We conducted a meta-Analysis of placebo-controlled studies evaluating the effects of citrus juices on bioavailability of cyclosporine. The studies were identified in PubMed, Cochrane CENTRAL, CINAHL, ISI Web of Knowledge, Psych Info International, Pharmaceutical Abstract (IPA), and reference lists of relevant papers. The weighted-mean difference (WMD) was calculated for net changes in the area under the curve (AUC) of cyclosporine. All studies conducted as placebo-controlled crossover studies in humans to compare the effect of citrus juices and control (drinking water) on AUC of cyclosporine and/or Cmin,ss were reviewed. All studies included were evaluated and extracted independently, and discrepancies were resolved through discussion.Results: Eighteen studies were identified. A subgroup analysis suggested that grapefruit juice significantly increased AUC of cyclosporine (WMD = 1762.5 ng·h/ml, 95%CI = 1178.9-2346.0 ng·h/ml, p > 0.001). While a meta-Analysis of all other types of citrus juices (tangerine juice, Seville orange juice, sweet orange juice, and citrus soda) except pomelo juice revealed no effect on the AUC of cyclosporine (WMD = -181.0 ng·h/ml,95%CI = -582.8-220.9 ng·h/ml, p > 0.5), a study of pomelo juice indicated a significant increase in the AUC of cyclosporine.Conclusions: Grapefruit juice intake increases oral bioavailability of cyclosporine in both healthy volunteers and renal transplant patients, whereas all other types of citrus juices may not have an influence on the oral bioavailability of cyclosporine. Current evidence suggests that pomelo juice may be able to increase cyclosporine oral bioavailability.