Advertisement
Research ArticleArticle

Impact of Curcumin-Induced Changes in P-Glycoprotein and CYP3A Expression on the Pharmacokinetics of Peroral Celiprolol and Midazolam in Rats

Wenxia Zhang, Theresa May Chin Tan and Lee-Yong Lim
Drug Metabolism and Disposition January 2007, 35 (1) 110-115; DOI: https://doi.org/10.1124/dmd.106.011072

Abstract

The aim of this study was to evaluate whether curcumin could modulate P-glycoprotein (P-gp) and CYP3A expression, and in turn modify the pharmacokinetic profiles of P-gp and CYP3A substrates in male Sprague-Dawley rats. Intragastric gavage of the rats with 60 mg/kg curcumin for 4 consecutive days led to a down-regulation of the intestinal P-gp level. There was a concomitant upregulation of hepatic P-gp level, but the renal P-gp level was unaffected. Curcumin also attenuated the CYP3A level in the small intestine but induced CYP3A expression in the liver and kidney. Regular curcumin consumption also caused the Cmax and area under the concentration-time curve (AUC0–8 and total AUC) of peroral celiprolol (a P-gp substrate with negligible cytochrome P450 metabolism) at 30 mg/kg to increase, but the apparent oral clearance (CLoral) of the drug was reduced. Similarly, rats treated with curcumin for 4 consecutive days showed higher AUC (AUC0–4 and total AUC) and lower CLoral for peroral midazolam (a CYP3A substrate that does not interact with the P-gp) at 20 mg/kg in comparison with vehicle-treated rats. In contrast, curcumin administered 30 min before the respective drug treatments did not significantly modify the pharmacokinetic parameters of the drugs. Analysis of the data suggests that the changes in the pharmacokinetic profiles of peroral celiprolol and midazolam in the rat model were contributed mainly by the curcumin-mediated down-regulation of intestinal P-gp and CYP3A protein levels, respectively.

Food-drug interactions, including those between herbs and drugs, have become a major concern in recent years. This may be attributed to a greater awareness as more research and therefore publicity is generated in this area (Johne et al., 1999; Piscitelli et al., 2002), as well as the growing popularity of herbs as complementary medicines (Tindle et al., 2005). Drug interactions have been reported with some herbal medicines and supplements, such as St. John's wort (Hypericum perforatum) (Johne et al., 1999) and garlic (Allium sativum) (Piscitelli et al., 2002). St. John's wort, in particular, has been relatively well researched, with the chronic intake of St. John's wort shown to reduce the oral bioavailability of drugs through an upregulation of the intestinal CYP3A4 and P-glycoprotein (P-gp) levels (Dürr et al., 2000; Mai et al., 2004).

Curcumin is a natural phenolic coloring component in Curcuma longa, usually called turmeric, which has long been widely used as a spice and medicinal agent in traditional Chinese and Indian medicines (Ammon and Wahl, 1991). In recent years, curcumin has attracted the attention of Western medical practitioners because of its potential application as a relatively safe therapeutic adjuvant for cancer patients (Sharma et al., 2001; Cruz-Correa et al., 2006). On this basis, Phase I clinical trials of curcumin in cancer patients have been initiated in the United Kingdom (Sharma et al., 2004) and Taiwan (Cheng et al., 2001). Given its regular consumption in certain populations, curcumin could also give rise to drug interactions because it has been reported to inhibit both the function and expression of the P-gp in human KB cells (Anuchapreeda et al., 2002). To date, however, there has been no report on whether curcumin could modulate the pharmacokinetics of drugs that are P-gp substrates, nor has any study correlated curcumin consumption to tissue P-gp expression. Moreover, the effects of curcumin on the CYP3A enzymes remain unknown. Given the colocalization and overlapping substrate specificities of the P-gp and CYP3A (Wacher et al., 1995), it will not be surprising for curcumin to also modulate the activity and expression of the CYP3A enzymes.

The objective of this study was to evaluate whether curcumin, when consumed on a regular basis, was capable of influencing the pharmacokinetic parameters of peroral P-gp and CYP3A4 substrates. To examine the basis for the interactions, we measured the P-gp and CYP3A proteins in the small intestine, liver, and kidney of male Sprague-Dawley (SD) rats following curcumin consumption over 4 days. Celiprolol, a P-gp substrate that is negligibly metabolized by CYP3A (Karlsson et al., 1993; Lilja et al., 2003), and midazolam, a CYP3A substrate that is not a substrate of the P-gp (Kim et al., 1999; Galetin et al., 2005), were used as model drugs.

Materials and Methods

Animals. Healthy male SD rats (220–250 g) were purchased from the Laboratory Animals Centre, National University of Singapore. Rats were housed in cages at the animal holding unit under controlled temperature (23–24°C) and a 12-h dark/light cycle. All the animal procedures were approved by the Animal Ethics Committee of the National University of Singapore.

Analysis of P-gp and CYP3A Protein Expression. Rats were randomly divided into two groups with four or five rats in each group. Rats in the treated group were gavaged (16-gauge gavage needle, Kent Scientific, Torrington, CT) once daily with curcumin (Sigma-Aldrich, St. Louis, MO) at 60 mg/kg/day (1% Tween 80 as vehicle) for 4 consecutive days. Rats in the control group were similarly gavaged with the equivalent volume (about 1 ml) of vehicle. Animals were allowed free access to food and water but were fasted overnight before scarification to reduce the intestinal content. On day 5, rats were euthanized by i.p. injection with 30 mg/kg pentobarbital, and the small intestine, liver, and kidney were excised, snap-frozen in liquid nitrogen, and stored at –80°C until analysis.

Samples for protein analysis were homogenized (50 mg of small intestine, 30 mg of liver, or 30 mg of kidney) in freshly prepared ice-cold lysis buffer using a pellet pestle (Sigma, St. Louis, MO) and then solubilized in lysis buffer for 20 min. The lysis buffer consisted of phosphate-buffered saline with 1% Triton X-100 and 1 mM each of phenylmethylsulfonyl fluoride, dithiothreitol, and protease inhibitor (Roche Diagnosis, Basel, Switzerland). The lysates were centrifuged at 10,000g for 20 min at 4°C (MIKRO 22R, Andreas Hettich GmbH and Co. KG, Tuttlingen, Germany), and the supernatant was collected and stored at –80°C until use.

Protein in the supernatant was quantified by the Bio-Rad (Hercules, CA) protein assay, and known quantities of albumin, similarly processed, were used as reference standards. Protein samples equivalent to 40 μg of protein were size-fractionated by electrophoresis on a 7.5% SDS-polyacrylamide gel (Mini-PROTEAN 3 System, Bio-Rad) at 150 V for 1 h and transferred to polyvinylidene difluoride membranes, which were blocked by overnight incubation in a buffer containing 5% nonfat milk, 200 mM NaCl, 50 mM Tris, and 0.1% Tween 20. The membranes were then probed with either the monoclonal anti-P-gp antibody C219 (1:1000, Signet Laboratories, Dedham, MA), anti-CYP3A2 polyclonal antibody (1:1000, BD Gentest, San Jose, CA), or anti-β-actin antibody as control (1:5000, Sigma) for 2 h. After washing thrice with Tris-buffered saline/Tween 20, each washing lasting 10 min, the membranes were incubated with secondary antibody labeled with horseradish peroxidase (1:10,000) for P-gp, β-actin (Amersham Biosciences, Piscataway, NJ), and CYP3A (Pierce, Rockford, IL), respectively, for 1 h at room temperature. The P-gp and CYP3A proteins were detected with the Supersignal West Femto chemiluminescence system (Pierce), whereas the β-actin protein was detected with the Supersignal West Pico chemiluminescence system (Pierce). Bands were visualized in X-ray film, and the band density was scanned and quantified using Quantity One 4.5.2 image analysis software (Bio-Rad). P-gp and CYP3A protein band intensities were normalized to the intensities of the β-actin protein band. Because C219 is known to cross-react with the gene product of mdr2 and this protein is highly expressed in the rat liver, the hepatic P-gp Western blot was also probed with another P-gp antibody, the C494 (1:1000, Signet Laboratories), which is not known to cross-react with this protein (Warrington et al., 2004). Findings were similar using this antibody.

Pharmacokinetic Studies. Rats were randomly divided into three groups, with five rats in each group. Rats assigned to the treatment group were gavaged (16-gauge gavage needle, Kent Scientific) with 60 mg/kg/day (1% Tween 80 as vehicle) of curcumin for 4 consecutive days. Tween 80 was added to the vehicle to ensure curcumin dissolution and accurate dosing. Rats in the coadministered and control groups were similarly administered with equivalent volume (about 1 ml) of the 1% Tween 80 vehicle, taking into consideration reports that suggest Tween 80 to have inhibitory effects on the function of P-gp and CYP3A (Mountfield et al., 2000; Zhang et al., 2003). All the rats were allowed free access to food and water. On day 5, rats in the control group continued to receive only the vehicle, but those in the coadministered and treatment groups were given 60 mg/kg of curcumin. Half an hour later, rats in all three groups were gavaged with 30 mg/kg celiprolol (Nycomed Pharma, Vienna, Austria) dissolved at 5 mg/ml in distilled water. At 0, 15, 30, 45, 60, 90, 120, 180, 240, 360, and 480 min following celiprolol administration, blood samples of about 120 μl were drawn from the saphenous vein and collected into heparinized microcuvettes (CB300, Sarstedt AG and Co., Nümbrecht, Germany). Blood samples were centrifuged for 10 min at 10,000g at 4°C to obtain plasma samples, which were frozen at –80°C until analysis.

The experimental protocols for the pharmacokinetic study of midazolam were similar to those described for celiprolol, except that the rats were dosed with midazolam. Dormicum, an injection containing 5 mg/ml midazolam (Roche Diagnosis), was administered to the rats by gavage at 20 mg/kg. Blood (∼120 μl) was sampled from the saphenous vein at 0, 5, 10, 20, 30, 45, 60, 90, 120, and 240 min after administration, and the plasma samples generated from the blood samples were stored at –80°C until analysis.

Doses of 30 mg/kg for celiprolol and 20 mg/kg for midazolam were chosen based on literature values. The celiprolol dose emulated the dose used in another pharmacokinetic study in SD rats to evaluate its role as a P-gp substrate (Cornaire et al., 2004). For midazolam, p.o. doses in the range of 15 to 20 mg/kg were often used to examine its role as a CYP3A substrate in the SD rat model (Kotegawa et al., 2002; Kanazu et al., 2005). The upper dose limit of 20 mg/kg was applied for this study.

High-Performance Liquid Chromatography Analysis of Plasma Celiprolol and Midazolam. Methods for the assay of plasma celiprolol and midazolam concentrations were adapted from those described by Caudron et al. (2004) and ter Horst et al. (2003), respectively. Propranolol and norclomipramine (both from Sigma) were the respective internal standards. Briefly, the plasma sample (50 μl) was mixed with 0.5 μl of internal standard solution (100 μg/ml in methanol) before the addition of 50 μl of acetonitrile to precipitate the plasma proteins. After vortex-mixing, the mixture was centrifuged at 10,000g at 4°C for 10 min, and 20 μl of the supernatant was subject to high-performance liquid chromatography (HPLC) analysis. The HPLC system consisted of an Agilent 1100 system (Agilent Technologies, Palo Alto, CA) with multiple-wavelength detector and a C18 column (200 × 4.6 mm, 5 μm) (Waters, Milford, MA) preceded by a C18 guard column (Waters). Isocratic elution was performed for both drugs at a flow rate of 1.0 ml/min. Mobile phase for celiprolol analysis consisted of 27% acetonitrile and 73% buffer solution (20 mM KH2PO4, pH 3.8), whereas that for midazolam analysis consisted of 36% acetonitrile and 64% buffer. The detection wavelengths of 231 and 250 nm were used for celiprolol and midazolam, respectively. The HPLC peaks were recorded and integrated using the Agilent data analysis software.

The HPLC was calibrated with celiprolol and midazolam in the concentration range of 0.05 to 3.2 μg/ml. The standard solutions were prepared by diluting stock solutions (drug and internal standard dissolved in methanol at 1 mg/ml) with blank plasma. The intraday and interday CV for celiprolol analysis were less than 9%, and the lower limit of quantification was 50 ng/ml. The average recovery for celiprolol was 106% over the concentration range. Typical retention times recorded for celiprolol and propranolol were 5.5 and 12.5 min, respectively. The intraday and interday CV for midazolam analysis were less than 10%, and the lower limit of quantification was 50 ng/ml. The average recovery for midazolam was 103% over the concentration range. Typical retention times recorded for midazolam and norclomipramine were 11.9 and 18.5 min, respectively.

Pharmacokinetic Analysis. Celiprolol and midazolam pharmacokinetics data were determined using the standard noncompartmental methods (Win-Nonlin 1.1, Pharsight, Mountain View, CA). Area under the plasma concentration-time curves of celiprolol from 0 to 8 h (AUC0–8) and of midazolam from 0 to 4 h (AUC0–4) were determined by use of the trapezoidal rule. The terminal elimination rate constant (ke) was calculated using the slope of the log-linear regression of the terminal elimination phase. Area under the plasma concentration versus time curve from zero to infinity (AUC0-∞) was calculated using the trapezoidal rule up to the last measured time concentration (Clast) with extrapolation to infinity using Clast/ke. The apparent oral clearance (CLoral) was calculated as dose/AUC0-∞. Peak plasma drug concentrations (Cmax) and the times when they occurred (tmax) were derived directly from the plasma concentration versus time curves.

Statistical Analysis. Statistical analysis of protein expression data was performed using the Student's t test, whereas the analysis of pharmacokinetic parameters was conducted using one-way analysis of variance, with the Tukey test applied for comparison of means (SPSS 10.0, SPSS Inc., Chicago, IL). A p ≤ 0.05 was considered statistically significant.

Fig. 1.
Fig. 1.

Effects of curcumin treatment on the expression of intestinal, hepatic, and renal P-gp. A, data analysis of Western blot results. B, image of Western blot results. Rats (n = 4–5) were gavaged once daily with 1% Tween 80 (control) or 60 mg/kg/day curcumin (treated) for 4 consecutive days. Intestine, liver, and kidney were collected on day 5. P-gp levels were measured using the C219 antibody as described under Materials and Methods. β-Actin was used as control. Bars represent mean ± S.E.M. of band densities of P-gp normalized to β-actin (*, p < 0.05).

Results

Effects of Curcumin on P-gp and CYP3A Protein Levels in Rodent Tissues. In the present study, we showed that curcumin consumption could cause the P-gp and CYP3A to be differentially regulated in the small intestine, liver, and kidney of male SD rats. After 4 days of treatment, there were no significant differences in mean body weight between the vehicle- and curcumin-treated rats (data not shown). P-gp protein levels in the intestinal, hepatic, and renal crude membranes isolated from the rats were determined by Western blot analysis using the C219 and C494 antibodies, with β-actin as control. The C219 anti-P-gp antibody recognized a protein band of about 170 kDa, consistent with the known molecular mass of P-gp. Compared with vehicle-treated rats, rats dosed with 60 mg/kg/day curcumin showed a 49% decrease in P-gp protein level in the small intestine after 4 days (p = 0.02), whereas the hepatic P-gp level was increased by 144% (p = 0.01). There was no change in the renal P-gp level (p = 1.00). Probing the hepatic P-gp protein with C494 antibody yielded comparable results as the C219 antibody (Fig. 1).

CYP3A protein level in the rodent tissues was determined by Western blot analysis using the polyclonal anti-rat CYP3A2 antibody. This antibody recognized one band of about 55 kDa in the liver tissues, but more than one band was detected for the small intestine and kidney tissues. Intestinal CYP3A protein level was observed to decrease by 42% after 4 days of treatment with 60 mg/kg/day curcumin (Fig. 2, p = 0.04), whereas the hepatic CYP3A protein level was increased by 91% (p = 0.05). Unlike the renal P-gp, the renal CYP3A protein level was enhanced by 41% after the curcumin treatment (Fig. 2, p = 0.02).

Fig. 2.
Fig. 2.

Effects of curcumin treatment on the expression of intestinal, hepatic, and renal CYP3A. A, data analysis of Western blot results. B, image of Western blot results. Rats (n = 4–5) were gavaged once daily with 1% Tween 80 (control) or 60 mg/kg/day curcumin (treated) for 4 consecutive days. Intestine, liver, and kidney were collected on day 5. CYP3A levels were measured using the anti-rat CYP3A2 antibody as described under Materials and Methods. β-Actin was used as control. Bars represent mean ± S.E.M. of band densities of CYP3A normalized to β-actin (*, p < 0.05).

Effects of Curcumin on Celiprolol Pharmacokinetics in Rats. Plasma celiprolol concentration-time profiles obtained after p.o. administration of 30 mg/kg celiprolol to rats in the control, coadministered, and treatment groups are shown in Fig. 3. The corresponding pharmacokinetic parameters are summarized in Table 1. Compared with rats in the control group, rats treated with curcumin for 4 days before drug administration showed significantly higher Cmax and AUC values. The Cmax, AUC0–8, and total AUC of celiprolol were, respectively, 1.9-(p = 0.01), 1.6-(p = 0.01), and 1.3-fold (p = 0.02) greater for rats in the treated group. However, CLoral value for celiprolol in the treatment group was 22% lower than the CLoral value for the control group (p = 0.01). By contrast, rats administered with curcumin 30 min before celiprolol treatment (coadministered group) did not have significantly different Cmax (p = 0.95), AUC0–8 (p = 0.83), total AUC (p = 0.19), and CLoral (p = 0.06) values compared with rats in the control group. Significant differences in Cmax (p = 0.01) and AUC0–8 (p = 0.04) were observed between rats in the coadministered and treatment groups, but there were no significant differences in total AUC (p = 0.32) and CLoral (p = 0.48) between these two groups. The tmax value was not significantly different among the three groups (Table 1, p > 0.05).

View this table:
TABLE 1

Pharmacokinetic parameters of celiprolol in rat plasma in control, coadministered, and treatment groups following a p.o. dose of 30 mg/kg

Data are presented as mean ± S.E.M. (n = 5).

Fig. 3.
Fig. 3.

Time course of the plasma concentrations of celiprolol in rats assigned to the control, coadministered, and treatment groups. Rats (n = 5) were gavaged once daily with 1% Tween 80 (control, diamonds; coadministered group, triangles) or 60 mg/kg/day curcumin (treatment, squares) for 4 consecutive days. On day 5, rats were gavaged with vehicle (control) or 60 mg/kg curcumin (coadministered and treatment groups) 30 min before they were gavaged with 30 mg/kg celiprolol. Data points represent mean ± S.E.M.

Fig. 4.
Fig. 4.

Time course of the plasma concentrations of midazolam in rats assigned to the control, coadministered, and treatment groups. Rats (n = 5) were gavaged once daily with 1% Tween 80 (control, diamonds; coadministered group, triangles) or 60 mg/kg/day curcumin (treatment, squares) for 4 consecutive days. On day 5, rats were gavaged with vehicle (control) or 60 mg/kg curcumin (coadministered and treatment group) 30 min before they were gavaged with 20 mg/kg midazolam. Data points represent mean ± S.E.M.

Effects of Curcumin on Midazolam Pharmacokinetics in Rats. Plasma midazolam concentration-time profiles obtained after p.o. administration of 20 mg/kg midazolam to rats in the control, coad-ministered, and treatment groups are shown in Fig. 4, and the pharmacokinetic parameters are summarized in Table 2. The tmax value of midazolam was not significantly different among the rats in the three groups (p > 0.05). However, rats in the treatment group showed higher AUC0–4 (2.6-fold, p = 0.04) and total AUC (3.8-fold, p = 0.03) values, as well as lower CLoral (75% lower, p = 0.02) values, compared with control. Cmax of midazolam was not significantly different (p = 0.10) between the treatment and control groups. In comparison, rats in the coadministered group did not show significantly different Cmax (p = 0.17), AUC0–4 (p = 0.29), total AUC (p = 0.79), and CLoral values (p = 0.15) from rats in the control group, nor were there significant differences in the Cmax (p = 0.94), AUC0–4 (p = 0.38), total AUC (p = 0.10), and CLoral values (p = 0.33) between rats in the coadministered and treatment groups.

View this table:
TABLE 2

Pharmacokinetic parameters of midazolam in rat plasma in control, coadministered, and treatment groups following a p.o. dose of 20 mg/kg

Data are presented as mean ± S.E.M. (n = 5).

Discussion

The overlapping tissue distribution of CYP3A and P-gp, as well as the broad spectrum of drugs that interact with both proteins, has presented significant challenges to drug absorption and delivery to the systemic circulation (Yasuda et al., 2002). Moreover, the interaction of coadministered drugs with CYP3A and P-gp in the gut can lead to major drug-drug interactions (Yasuda et al., 2002). Given the substantial overlaps in substrate, inducer, and inhibitor specificities between the P-gp and CYP3A, it is important to understand the relative contribution of CYP3A and P-gp to specific drug interactions (Wacher et al., 1995; Yasuda et al., 2002). Inhibition and induction of the CYP3A have been shown to, respectively, reduce and enhance the metabolism of drugs that are CYP3A substrates, and to consequently alter their pharmacokinetic profiles (Luo et al., 2003; Chaobal and Kharasch, 2005). Conversely, the inhibition and induction of P-gp would have opposite effects on the fate of coadministered drugs that are P-gp substrates (Luo et al., 2003; Gurley et al., 2006).

Our results show that curcumin was a modulator of P-gp and CYP3A expression in the rat. Significantly, the curcumin administered p.o. was capable of not only changing the P-gp and CYP3A protein levels in the rodent intestine, but also it modified the P-gp and CYP3A levels in the rodent liver and kidney. Curcumin administered p.o. is known to be absorbed into the systemic circulation in rats (Ravindranath and Chandrasekhara, 1980) and humans (Sharma et al., 2001). However, it is reported to have a relatively low oral bioavailability of about 60% (Ravindranath and Chandrasekhara, 1980) because of extensive metabolism by human phenol sulfotransferase isoenzymes (SULT1A1 and SULT1A3) and equine alcohol dehydrogenase (Ireson et al., 2002). Nevertheless, peroral curcumin has been shown in this study to exert both local and systemic effects on protein expression when it was administered to the rats at a dose of 60 mg/kg/day for 4 days. The cumulative absorption of curcumin into the general circulation was adequate to modify the expression of P-gp and CYP3A in the hepatic and renal tissues.

Data in this study also implicate the presence of differential regulatory mechanisms for protein expression in the rodent organs. Curcumin concomitantly suppressed the P-gp and CYP3A protein levels in the rodent intestine yet up-regulated the expression of these proteins in the rodent liver. Moreover, the P-gp and CYP3A levels in the liver and intestine were not coordinately regulated, which is consistent with the findings of Lown et al. (1994), who showed that the hepatic CYP3A4 activity in humans did not correlate with the intestinal CYP3A4 activity and protein content. Such tissue-specific response of P-gp and/or CYP3A expression to treatment has been reported by other researchers (Hartmann et al., 2005) and is thought to facilitate the removal of potentially toxic substances in abnormal states where the excretory capacity of a specific organ is diminished. There is evidence that curcumin may modulate the transcription of CYP3A through the pregnane X receptor (PXR) (Liu et al., 2006). Because the activation of PXR is known also to influence the expression of the P-gp protein (Synold et al., 2001), the regulating effect of curcumin on P-gp expression may well occur through its regulation of the PXR.

Pharmacokinetic profiles of celiprolol and midazolam were different in rats fed with 60 mg/kg/day curcumin for 4 days compared with control rats. Such pharmacokinetic modulations might be attributed to changes in the function and/or expression of proteins that participate in the transport and metabolism of the drugs. Indeed, curcumin has been shown to inhibit P-gp efflux activity in vitro (Anuchapreeda et al., 2002), and studies in our laboratory have indicated that it also attenuates the activity of CYP3A enzymes in liver microsomes. However, the administration of a single dose of curcumin 30 min before drug treatment did not modify the pharmacokinetic profiles of either celiprolol or midazolam, indicating that the pharmacokinetic changes were unlikely to be contributed by modifications in protein function. Rather, they were caused by the curcumin-mediated changes in tissue P-gp and CYP3A levels.

Cmax, AUC0–8, and total AUC of celiprolol, a P-gp substrate, were increased, whereas its systemic clearance was reduced in rats fed with curcumin for 4 days. These findings were in agreement with another study, in which the inhibition of intestinal P-gp by clarithromycin in humans caused the Cmax and AUC of digoxin, another P-gp substrate, to increase (Gurley et al., 2006). The inhibition of renal P-gp by clarithromycin also reduced the CLoral of digoxin (Gurley et al., 2006), which is largely eliminated by renal excretion (Doherty et al., 1977). Celiprolol, on the other hand, is excreted equally into the urine and the bile (Pruss et al., 1988). Its clearance via the kidney was unlikely to be significantly affected by curcumin, which did not alter the renal P-gp protein level. The hepatic P-gp also appeared to play a minor role in influencing the pharmacokinetics of celiprolol. This is because curcumin mediated an up-regulation of the hepatic P-gp level, whereas a down-regulation of hepatic P-gp level would be more in line with the observed increased Cmax and AUC of celiprolol and its decreased systemic clearance via biliary elimination (Hartmann et al., 2005). Therefore, it may be concluded that the down-regulation of intestinal P-gp level by curcumin was influential in increasing the oral bioavailability of celiprolol. By its effect on the enterohepatic circulation of the drug, the lower P-gp level could also reduce the systemic clearance of celiprolol. The importance of the intestinal P-gp, relative to those in the liver and kidney, in influencing drug bioavailability is not unusual and has been shown by Greiner et al. (1999) for digoxin and by Lown et al. (1997) for cyclosporine.

Curcumin consumed over 4 consecutive days also caused the AUC of midazolam to increase, whereas the CLoral of midazolam was reduced. These results are consistent with the changes in CYP3A level in the rodent tissues. Midazolam is almost entirely eliminated by CYP3A-mediated metabolism (Kronbach et al., 1989), and because it is not a substrate of P-gp (Kim et al., 1999), its pharmacokinetic profile would not be affected by the coregulation of P-gp by curcumin. Pharmacokinetic studies have consistently associated an up-regulation of hepatic and/or intestinal CYP3A level with decreased oral bioavailability and increased systemic clearance of CYP3A substrates (Dürr et al., 2000; Dresser et al., 2003; Mai et al., 2004). Conversely, the down-regulation of CYP3A in either tissue would have opposite consequences. Clinical studies have further shown midazolam to have lower AUC following intestinal and hepatic CYP3A induction by rifampin and higher AUC after intestinal and hepatic CYP3A inhibition by troleandomycin (Chaobal and Kharasch, 2005). Although CYP3A in the kidney may also contribute to drug metabolism, the up-regulation of renal CYP3A expression by curcumin is not expected to play an important role in the CLoral of midazolam. Despite the plethora of absorption, distribution, metabolism, and excretion studies on midazolam, none to date has implicated renal metabolism as a significant route for the systemic clearance of midazolam. In the present study, curcumin caused a 91% up-regulation of hepatic CYP3A protein level compared with a 41% elevation of renal CYP3A. This makes it even less likely for renal metabolism to exert a predominant influence on the systemic clearance of midazolam following spice administration. Taken together, the data in this study suggest that the curcumin-mediated down-regulation of the intestinal CYP3A protein level was the main contributing factor for the increased oral bioavailability and decreased systemic clearance of midazolam.

In summary, curcumin-induced regulation of P-gp and CYP3A expression in the rat tissues can cause changes to the pharmacokinetic profiles of celiprolol, a P-gp substrate, and midazolam, a CYP3A substrate. The implication is that the regular consumption of curcumin by certain populations could probably influence the pharmacokinetics of drugs that are P-gp and/or CYP3A substrates. Our data suggest that it is imperative to conduct quantitative evaluation of curcumin-drug interactions in human subjects to provide a better understanding of the effects of curcumin on population pharmacokinetics. It will also allow for predictive clinical intervention to be made so that undesirable curcumin-drug interactions can be avoided in susceptible populations.

Acknowledgments

Celiprolol HCl was a gift from Nycomed Pharma, Vienna, Austria.

Footnotes

  • This study was supported by a fund from the Biomedical Research Council, Singapore (01/1/21/19/142). Wenxia Zhang is the recipient of a graduate scholarship from the National University of Singapore.

  • Article, publication date, and citation information can be found at http://dmd.aspetjournals.org.

  • doi:10.1124/dmd.106.011072.

  • ABBREVIATIONS: P-gp, P-glycoprotein; SD, Sprague-Dawley; HPLC, high-performance liquid chromatography; AUC, area under the concentration curve; PXR, pregnane X receptor.

    • Received May 17, 2006.
    • Accepted October 17, 2006.

References

  1. ↵
    Ammon HPT and Wahl MA (1991) Pharmacology of Curcuma longa. Planta Med 57: 1–7.
    OpenUrlCrossRefPubMed
  2. ↵
    Anuchapreeda S, Leechanachai P, Smith M, Ambudkar SV, and Limtrakul P (2002) Modulation of P-glycoprotein expression and function by curcumin in multidrug resistant human KB cells. Biochem Pharmacol 64: 573–582.
    OpenUrlCrossRefPubMed
  3. ↵
    Caudron E, Laurent S, Billaud EM, and Prognon P (2004) Simultaneous determination of the acid/base antihypertensive drugs celiprolol, bisoprolol and irbesartan in human plasma by liquid chromatography. J Chromatogr B Analyt Technol Biomed Life Sci 801: 339–345.
    OpenUrlPubMed
  4. ↵
    Chaobal HN and Kharasch ED (2005) Single-point sampling for assessment of constitutive, induced, and inhibited cytochrome P450 3A activity with alfentanil or midazolam. Clin Pharmacol Ther 78: 529–539.
    OpenUrlCrossRefPubMed
  5. ↵
    Cheng AL, Hsu CH, Lin JK, Hsu MM, Ho YF, Shen TS, Ko JY, Lin JT, Lin BR, Ming-Shiang W, et al. (2001) Phase I clinical trial of curcumin, a chemopreventive agent, in patients with high-risk or pre-malignant lesions. Anticancer Res 21: 2895–2900.
    OpenUrlPubMed
  6. ↵
    Cornaire G, Woodley J, Hermann P, Cloarec A, Arellano C, and Houin G (2004) Impact of excipients on the absorption of P-glycoprotein substrates in vitro and in vivo. Int J Pharm (Amst) 278: 119–131.
    OpenUrlCrossRef
  7. ↵
    Cruz-Correa M, Shoskes DA, Sanchez P, Zhao R, Hylind LM, Wexner SD, and Giardiello FM (2006) Combination treatment with curcumin and quercetin of adenomas in familial adenomatous polyposis. Clin Gastroenterol Hepatol 4: 1035–1038.
    OpenUrlCrossRefPubMed
  8. ↵
    Doherty JE, Dalrymple GV, Murphy ML, Kane JJ, Bissett JK, and de Soyza N (1977) Pharmacokinetics of digoxin. Fed Proc 36: 2242–2246.
    OpenUrlPubMed
  9. ↵
    Dresser GK, Schwartz UI, Wilkinson GR, and Kim RB (2003) Coordinate induction of both cytochrome P4503A and MDR1 by St. John's wort in healthy subjects. Clin Pharmacol Ther 73: 41–50.
    OpenUrlCrossRefPubMed
  10. ↵
    Dürr D, Stieger B, Kullak-Ublick GA, Rentsch KM, Steinert HC, Meier PJ, and Fattinger K (2000) St. John's wort induces intestinal P-glycoprotein/MDR1 and intestinal and hepatic CYP3A4. Clin Pharmacol Ther 68: 598–604.
    OpenUrlCrossRefPubMed
  11. ↵
    Galetin A, Ito K, Hallifax D, and Houston JB (2005) CYP3A4 substrate selection and substitution in the prediction of potential drug-drug interactions. J Pharmacol Exp Ther 314: 180–190.
    OpenUrlAbstract/FREE Full Text
  12. ↵
    Greiner B, Eichelbaum M, Fritz P, Kreichgauer HP, von Richter O, Zundler J, and Kroemer HK (1999) The role of intestinal P-glycoprotein in the interaction of digoxin and rifampin. J Clin Investig 104: 147–153.
    OpenUrlCrossRefPubMed
  13. ↵
    Gurley BJ, Barone GW, Williams DK, Carrier J, Breen P, Yates CR, Song PF, Hubbard MA, Tong Y, and Cheboyina S (2006) Effect of milk thistle (Silybum marianum) and black cohosh (Cimicifuga racemosa) supplementation on digoxin pharmacokinetics in humans. Drug Metab Dispos 34: 69–74.
    OpenUrlAbstract/FREE Full Text
  14. ↵
    Hartmann G, Vassileva V, and Piquette-Miller M (2005) Impact of endotoxin-induced changes in P-glycoprotein expression on disposition of doxorubicin in mice. Drug Metab Dispos 33: 820–828.
    OpenUrlAbstract/FREE Full Text
  15. ↵
    Ireson CR, Jones DJ, Orr S, Coughtrie MW, Boocock DJ, Williams ML, Farmer PB, Steward WP, and Gescher AJ (2002) Metabolism of the cancer chemopreventive agent curcumin in human and rat intestine. Cancer Epidemiol Biomarkers Prev 11: 105–111.
    OpenUrlAbstract/FREE Full Text
  16. ↵
    Johne A, Brockmöller J, Bauer S, Maurer A, Langheinrich M, and Roots I (1999) Pharmacokinetic interaction of digoxin with an herbal extract from St. John's wort (Hypericum perforatum). Clin Pharmacol Ther 66: 338–345.
    OpenUrlCrossRefPubMed
  17. ↵
    Kanazu T, Okamura N, Yamaguchi Y, Baba T, and Koike M (2005) Assessment of the hepatic and intestinal first-pass metabolism of midazolam in a CYP3A drug-drug interaction model rats. Xenobiotica 35: 305–317.
    OpenUrlCrossRefPubMed
  18. ↵
    Karlsson J, Kuo SM, Ziemniak J, and Artursson P (1993) Transport of celiprolol across human intestinal epithelial (Caco-2) cells: mediation of secretion by multiple transporters including P-glycoprotein. Br J Pharmacol 110: 1009–1016.
    OpenUrlPubMed
  19. ↵
    Kim RB, Wandel C, Leake B, Cvetkovic M, Fromm MF, Dempsey PJ, Roden MM, Belas F, Chaudhary AK, Roden DM, et al. (1999) Interrelationship between substrates and inhibitors of human CYP3A and P-glycoprotein. Pharm Res (NY) 16: 408–414.
    OpenUrl
  20. ↵
    Kotegawa T, Laurijssens BE, Von Moltke LL, Cotreau MM, Perloff MD, Venkatakrishnan K, Warrington JS, Granda BW, Harmatz JS, and Greenblatt DJ (2002) In vitro, pharmacokinetic, and pharmacodynamic interactions of ketoconazole and midazolam in the rat. J Pharmacol Exp Ther 302: 1228–1237.
    OpenUrlAbstract/FREE Full Text
  21. ↵
    Kronbach T, Mathys D, Umeno M, Gonzalez FJ, and Meyer UA (1989) Oxidation of midazolam and triazolam by human liver cytochrome P450IIIA4. Mol Pharmacol 36: 89–96.
    OpenUrlAbstract
  22. ↵
    Lilja JJ, Backman JT, Laitila J, Luurila H, and Neuvonen PJ (2003) Itraconazole increases but grapefruit juice greatly decreases plasma concentrations of celiprolol. Clin Pharmacol Ther 73: 192–198.
    OpenUrlCrossRefPubMed
  23. ↵
    Liu DY, Yang M, Zhu HJ, Zheng YF, and Zhu XQ (2006) Human pregnane X receptor-mediated transcriptional regulation of cytochrome P450 3A4 by some phytochemicals. Zhejiang Da Xue Xue Bao Yi Xue Ban 35: 8–13.
    OpenUrlPubMed
  24. ↵
    Lown KS, Kolars JC, Thummel KE, Barnett JL, Kunze KL, Wrighton SA, and Watkins PB (1994) Interpatient heterogeneity in expression of CYP3A4 and CYP3A5 in small bowel. Lack of prediction by the erythromycin breath test. Drug Metab Dispos 22: 947–955.
    OpenUrlAbstract
  25. ↵
    Lown KS, Mayo RR, Leichtman AB, Hsiao HL, Turgeon DK, Schmiedlin-Ren P, Brown MB, Guo W, Rossi SJ, Benet LZ, et al. (1997) Role of intestinal P-glycoprotein (mdr1) in interpatient variation in the oral bioavailability of cyclosporine. Clin Pharmacol Ther 62: 248–260.
    OpenUrlCrossRefPubMed
  26. ↵
    Luo G, Lin J, Fiske WD, Dai R, Yang TJ, Kim S, Sinz M, LeCluyse E, Solon E, Brennan JM, et al. (2003) Concurrent induction and mechanism-based inactivation of CYP3A4 by an L-valinamide derivative. Drug Metab Dispos 31: 1170–1175.
    OpenUrlAbstract/FREE Full Text
  27. ↵
    Mai I, Bauer S, Perloff ES, Johne A, Uehleke B, Frank B, Budde K, and Roots I (2004) Hyperforin content determines the magnitude of the St John's wort-cyclosporine drug interaction. Clin Pharmacol Ther 76: 330–340.
    OpenUrlCrossRefPubMed
  28. ↵
    Mountfield RJ, Senepin S, Schleimer M, Walter I, and Bittner B (2000) Potential inhibitory effects of formulation ingredients on intestinal cytochrome P450. Int J Pharm (Amst) 211: 89–92.
    OpenUrlCrossRef
  29. ↵
    Piscitelli SC, Burstein AH, Welden N, Gallicano KD, and Falloon J (2002) The effect of garlic supplements on the pharmacokinetics of saquinavir. Clin Infect Dis 34: 234–238.
    OpenUrlAbstract/FREE Full Text
  30. ↵
    Pruss TP, Lamon KD, and Hagen NS (1988) Celiprolol— overview of 6 years of clinical trials experience. J Int Med Res 16: 17A–22A.
    OpenUrl
  31. ↵
    Ravindranath V and Chandrasekhara N (1980) Absorption and tissue distribution of curcumin in rats. Toxicology 16: 259–265.
    OpenUrlCrossRefPubMed
  32. ↵
    Sharma RA, Euden SA, Platton SL, Cooke DN, Shafayat A, Hewitt HR, Marczylo TH, Morgan B, Hemingway D, Plummer SM, et al. (2004) Phase I clinical trial of oral curcumin: biomarkers of systemic activity and compliance. Clin Cancer Res 10: 6847–6854.
    OpenUrlAbstract/FREE Full Text
  33. ↵
    Sharma RA, McLelland HR, Hill KA, Ireson CR, Euden SA, Manson MM, Pirmohamed M, Marnett LJ, Gescher AJ, and Steward WP (2001) Pharmacodynamic and pharmacokinetic study of oral Curcuma extract in patients with colorectal cancer. Clin Cancer Res 7: 1894–1900.
    OpenUrlAbstract/FREE Full Text
  34. ↵
    Synold TW, Dussault I, and Forman BM (2001) The orphan nuclear receptor SXR coordinately regulates drug metabolism and efflux. Nat Med 7: 584–590.
    OpenUrlCrossRefPubMed
  35. ↵
    ter Horst PG, Foudraine NA, Cuypers G, van Dijk EA, and Oldenhof NJ (2003) Simultaneous determination of levomepromazine, midazolam and their major metabolites in human plasma by reversed-phase liquid chromatography. J Chromatogr B Analyt Technol Biomed Life Sci 791: 389–398.
    OpenUrlPubMed
  36. ↵
    Tindle HA, Davis RB, Phillips RS, and Eisenberg DM (2005) Trends in use of complementary and alternative medicine by US adults: 1997–2002. Altern Ther Health Med 11: 42–49.
    OpenUrlPubMed
  37. ↵
    Wacher VJ, Wu CY, and Benet LZ (1995) Overlapping substrate specificities and tissue distribution of cytochrome P450 3A and P-glycoprotein: implications for drug delivery and activity in cancer chemotherapy. Mol Carcinog 13: 129–134.
    OpenUrlCrossRefPubMed
  38. ↵
    Warrington JS, Greenblatt DJ, and von Moltke LL (2004) The effect of age on P-glycoprotein expression and function in the Fischer-344 rat. J Pharmacol Exp Ther 309: 730–736.
    OpenUrlAbstract/FREE Full Text
  39. ↵
    Yasuda K, Lan LB, Sanglard D, Furuya K, Schuetz JD, and Schuetz EG (2002) Interaction of cytochrome P450 3A inhibitors with P-glycoprotein. J Pharmacol Exp Ther 303: 323–332.
    OpenUrlAbstract/FREE Full Text
  40. ↵
    Zhang H, Yao M, Morrison RA, and Chong S (2003) Commonly used surfactant, Tween 80, improves absorption of P-glycoprotein substrate, digoxin, in rats. Arch Pharm Res (NY) 26: 768–772.
    OpenUrl
Back to top

In this issue

Download PDF
Article Alerts
Email Article
Citation Tools
Research ArticleArticle

Impact of Curcumin-Induced Changes in P-Glycoprotein and CYP3A Expression on the Pharmacokinetics of Peroral Celiprolol and Midazolam in Rats

Wenxia Zhang, Theresa May Chin Tan and Lee-Yong Lim
Drug Metabolism and Disposition January 1, 2007, 35 (1) 110-115; DOI: https://doi.org/10.1124/dmd.106.011072
del.icio.us logo Digg logo Reddit logo Twitter logo CiteULike logo Facebook logo Google logo Mendeley logo

Jump to section

Advertisement