BackgroundThis study aimed to investigate the therapeutic effect of curcumin in lipopolysaccharide (LPS) induced neonatal acute lung injury (ALI) and the possibly associated molecular mechanisms.Material/MethodsALI neonatal animal model was established by using LPS. Curcumin and/or peroxisome proliferator-activated receptor γ (PPARγ) inhibitor BADGE (bisphenol A diglycidyl ether) were administrated to animals. Lung edema was evaluated by PaO2 and lung wet/dry weight ratio (W/D) measurements. EMSA was used to determine the PPARγ activity. Levels of high-mobility group box 1 (HMGB1), secretory receptor for advanced glycation end products (RAGE), tumor necrosis factor α (TNFα), interleukin 6 (IL6), and transforming growth factor β1 (TGFβ1) in bronchoalveolar lavage fluid (BALF) were examined by ELISA. Western blotting was used to evaluate the expression levels of HMGB1, RAGE, heme oxygenase 1 (HO1), TNFα, IL6, and TGFβ1 in lung tissue.ResultsCurcumin administration significantly improved lung function by increasing PaO2 and decreasing W/D in neonatal ALI rats. Curcumin treatment upregulated the PPARγ activity and expression level of HO1 which were suppressed in lung tissue of neonatal ALI rats. Elevated levels of HMGB1, RAGE, TNFα, IL6, and TGFβ1 in both lung tissue and BALF from neonatal ALI rats were decreased dramatically by curcumin treatment. PPARγ inhibitor BADGE administration impaired curcumin’s alleviation on lung edema, inhibitory effects on inflammatory cytokine expression and recovery of PPARγ/HO1 signaling activation.ConclusionsCurcumin alleviated lung edema in LPS-induced ALI by inhibiting inflammation which was induced by PPARγ/HO1 regulated-HMGB1/RAGE pro-inflammatory pathway.

BackgroundArtequick is a relatively inexpensive artemisinin (Qing-hao-su; QHS)-based combination therapy (ACT) that contains QHS and piperaquine (PQ), which has not been widely used because of the decreased concentration level of QHS after repeated oral administrations for five to seven days as a monotherapy. This study was designed to evaluate the potential auto-induction metabolism of QHS in healthy Chinese adults after a two-day oral administration of QHS-PQ. The effect of QHS-PQ on the activity of the CYP2B6 and CYP3A4 was also investigated.MethodsFourteen healthy Chinese subjects received two-day oral doses of QHS-PQ (Artequick). A two-drug cocktail consisting of bupropion and midazolam was used to assess the activities of CYP2B6 and CYP3A, respectively. Plasma samples were analysed for QHS and its phase I/II metabolites, probe drugs and their metabolites, using a validated liquid chromatography tandem mass spectrometric (LC-MS) method.ResultsFour major phase I metabolites of QHS (M1-M3 and deoxy-QHS) and two subsequent phase II metabolites (M4-M5) were detected in human plasma after oral administrations of QHS-PQ. The AUC 0-t of the QHS and its phase I metabolites decreased significantly (P < 0.05) with increased oral clearance (CL/F) after two-day oral doses of QHS-PQ, whereas its phase II metabolites exhibited higher AUC (P < 0.01). The phase I metabolic capability, calculated by the AUC 0-t ratio of all phase I metabolites to QHS, increased 1.5-fold after the repeated dose (P < 0.01), and the phase II metabolic capability increased 1.5-fold for M4 and 3.0-fold for M5. The enzyme activity of CYP2B6 and CYP3A4 increased 2.1-fold and 3.2-fold, respectively, after two-day oral doses of QHS-PQ.ConclusionsThe auto-induction of both phase I and phase II metabolism of QHS was present in healthy Chinese subjects after a recommended two-day oral dose of QHS-PQ. The auto-induction metabolism also existed for phase I metabolites of QHS. The enzyme activity of CYP2B6 and CYP3A4 was induced after the two-day oral doses of QHS-PQ. Based on these results, the alternative common three-day regimen for QHS-PQ could probably lead to lower bioavailability of QHS and higher potential of drug-drug interaction caused by the induction of drug-metabolizing enzymes.

The traditional antimalarial herb Artemisia annua L., from which artemisinin is isolated, is widely used in endemic regions. It has been suggested that artemisinin activity can be enhanced by flavonoids in A. annua; however, how fast and how long the flavonoids are present in the body remains unknown. In the present study, a rapid and sensitive liquid chromatography with tandem mass spectrometry method was developed and validated for the simultaneous determination of three major flavonoids components, i.e. chrysosplenol D, chrysoplenetin, and artemetin and their glucuronidated metabolites in rats after oral administrations of A. annua extracts at a therapeutic ultra‐low dose. The concentration of the intact form was determined directly, and the concentration of the glucuronidated form was assayed in the form of flavonoids aglycones, after treatment with β‐glucuronidase/sulfatase. The method was linear in the range of 0.5–300.0 ng/mL for chrysoplenetin and artemetin, and 2–600 ng/mL for chrysosplenol D. All the validation data conformed to the acceptance requirements. The study revealed a significantly higher exposure of the flavonoid constituents in conjugated forms in rats, with only trace intact from. Multiple oral doses of A. annua extracts led to a decreased plasma concentration levels for three flavonoids.

BackgroundDihydroartemisinin (DHA) is a component of artemisinin-based combination therapy (ACT), which is widely recommended for treatment of uncomplicated falciparum malaria. DHA is also the main metabolite of artemether and artesunate, both of which are used in ACT. Due to auto-induction metabolism, declining plasma concentrations after the repeated dosing have been reported for artemisinin (Qing-hao-su) and artemether. This study was designed to evaluate the potential auto-induction metabolism of DHA in healthy Chinese adults after multiple oral doses of DHA. The polymorphic effects of UGT1A9 (I399C>T) and UGT2B7*2 (802C>T), the major enzymes involved in the metabolism of DHA, on the pharmacokinetic profiles of DHA and its metabolite was also studied.MethodsSixteen healthy Chinese subjects (four I399TT/802CC, four I399CC/802TT, four I399TT/802TT and four I399CT/802CT) received four recommended oral doses of Artekin, an ACT containing DHA (80 mg/dose) and piperaquine (PQ; 640 mg/dose), at 0, 6, 24 and 32 h. Plasma samples were analysed for DHA and its metabolite using a validated liquid chromatography tandem mass spectrometric (LC-MS) method.ResultsDHA and its glucuronidated metabolite DHA-Glu were detected in human plasma after oral administration of DHA-PQ. Compared with the first dose, the AUC0-t of the parent drug DHA decreased significantly (P<0.01) with increased oral clearance (CL/F) after each repeated dose of DHA-PQ, whereas its metabolite DHA-Glu did not change (P>0.05) in AUC0-t or Cmax. The phase II metabolic capability, calculated by the AUC0-t ratio of DHA-Glu to the parent drug DHA, increased 1.5-fold (90% CI, 1.3-1.7), 1.2-fold (90% CI, 1.1-1.3) and 1.7-fold (90% CI, 1.5-1.8) after the second, third and fourth dose, respectively. No polymorphic effect was found for UGT1A9 (I399C>T) and UGT2B7*2 (802C>T) on the pharmacokinetic profiles of DHA and its metabolite DHA-Glu.ConclusionsThe auto-induction phase II metabolism of DHA was present in healthy Chinese subjects after the recommended two-day oral doses of DHA-PQ (Artekin). The metabolic capability could recover after a 12-h dosing interval, which suggested that the alternative common three-day regimen (once daily) for DHA-PQ could probably lead to higher bioavailability of DHA. The polymorphism of UGT1A9 (I399C>T) and UGT2B7*2 (802C>T) may not be a concern during the treatment with DHA.Electronic supplementary materialThe online version of this article (doi:10.1186/1475-2875-13-478) contains supplementary material, which is available to authorized users.

Artemisinin-based combination therapy is widely used for the treatment of uncomplicated Plasmodium falciparum malaria, and piperaquine (PQ) is one of important partner drugs. The pharmacokinetics of PQ is characterized by a low clearance and a large volume of distribution; however, metabolism of PQ has not been thoroughly investigated. In this work, the metabolite profiling of PQ in human and rat was studied using liquid chromatography tandem high-resolution LTQ-Orbitrap mass spectrometry (HRMS). The biological samples were pretreated by solid-phase extraction. Data processes were carried out using multiple data-mining techniques in tandem, i.e., isotope pattern filter followed by mass defect filter. A total of six metabolites (M1-M6) were identified for PQ in human (plasma and urine) and rat (plasma, urine and bile). Three reported metabolites were also found in this study, which included N-oxidation (M1, M2) and carboxylic products (M3). The subsequent N-oxidation of M3 resulted in a new metabolite M4 detected in urine and bile samples. A new metabolic pathway N-dealkylation was found for PQ in human and rat, leading to two new metabolites (M5 and M6). This study demonstrated that LC-HRMS(n) in combination with multiple data-mining techniques in tandem can be a valuable analytical strategy for rapid metabolite profiling of drugs. Copyright © 2016 John Wiley & Sons, Ltd.

As a partner antimalarial for artemisinin drug-based combination therapy (ACT), piperaquine (PQ) can be metabolized into two major metabolites, including piperaquine -oxide (M1) and piperaquine,-dioxide (M2). To better understand the antimalarial potency of PQ, the antimalarial activity of the PQ metabolites (M1 and M2) was studied (in strains 3D7 andDd2) and (in the murine species) in this study. The recrudescence and survival time of infected mice were also recorded after drug treatment. The pharmacokinetic profiles of PQ and its two metabolites (M1 and M2) were investigated in healthy subjects after oral doses of two widely used ACT regimens, i.e., dihydroartemisinin plus piperaquine phosphate (Duo-Cotecxin) and artemisinin plus piperaquine (Artequick). Remarkable antiplasmodial activity was found for PQ (50% growth-inhibitory concentration [IC], 4.5 nM against 3D7 and 6.9 nM againstDd2; 90% effective dose [ED], 1.3 mg/kg of body weight), M1 (IC, 25.5 nM against 3D7 and 38.7 nM againstDd2; ED, 1.3 mg/kg), and M2 (IC, 31.2 nM against 3D7 and 33.8 nM againstDd2; ED, 2.9 mg/kg). Compared with PQ, M1 showed comparable efficacy in terms of recrudescence and survival time and M2 had relatively weaker antimalarial potency. PQ and its two metabolites displayed a long elimination half-life (∼11 days for PQ, ∼9 days for M1, and ∼4 days for M2), and they accumulated after repeated administrations. The contribution of the two PQ metabolites to the efficacy of piperaquine as a partner drug of ACT for the treatment of malaria should be considered for PQ dose optimization.

A sensitive and efficient liquid chromatography tandem mass spectrometry method was developed and validated for the simultaneous determination of piperaquine (PQ) and its N-oxidated metabolite (PQ-M) in plasma. A simple protein precipitation procedure was used for sample preparation. Adequate chromatographic retention was achieved on a C column under gradient elution with acetonitrile and 2 mm aqueous ammonium acetate containing 0.15% formic acid and 0.05% trifluoroacetic acid. A triple-quadrupole mass spectrometer equipped with an electrospray source was set up in the positive ion mode and multiple reaction monitoring mode. The method was linear in the range of 2.0-400.0 ng/mL for PQ and 1.0-50.0 ng/mL for PQ-M with suitable accuracy, precision and extraction recovery. The lower limits of detection (LLOD) were established at 0.4 and 0.2 ng/mL for PQ and PQ-M, respectively, using 40 μL of plasma sample. The matrix effect was negligible under the current conditions. No effect was found for co-administrated artemisinin drugs or hemolysis on the quantification of PQ and PQ-M. Stability testing showed that two analytes remained stable under all relevant analytical conditions. The validated method was successfully applied to a pharmacokinetic study performed in rats after a single oral administration of PQ (60 mg/kg).

No abstract