Acupoint nanocomposite hydrogel for simulation of acupuncture and targeted delivery of triptolide against rheumatoid arthritis.

BACKGROUND: Attenuating inflammatory response and relieving pain are two therapeutic therapeutical goals for rheumatoid arthritis (RA). Anti-inflammatory and analgesic drugs are often associated with many adverse effects due to nonspecific distribution. New drug delivery systems with practical targeting ability and other complementary strategies urgently need to be explored. To achieve this goal, an acupoint drug delivery system that can target deliver anti-inflammatory drugs and simulate acupuncture in relieving pain was constructed, which can co-deliver triptolide (TP) and 2-chloro-N (6)-cyclopentyl adenosine (CCPA). RESULTS: We have successfully demonstrated that acupoint nanocomposite hydrogel composed of TP-Human serum album nanoparticles (TP@HSA NPs) and CCPA could effectively treat RA. The result shows that CCPA-Gel can enhance analgesic effects specifically at the acupoint, while the mechanical and thermal pain threshold was 4.9 and 1.6 times compared with non-acupoint, respectively, and the nanocomposite gel further enhanced. Otherwise, the combination of acupoint and nanocomposite hydrogel exerted synergetic improvement of inflammation, bone erosion, and reduction of systemic toxicity. Furthermore, it could regulate inflammatory factors and restore the balance of Th17/Treg cells, which provided a novel and effective treatment strategy for RA. Interestingly, acupoint administration could improve the accumulation of the designed nanomedicine in arthritic paws (13.5% higher than those in non-acupoint at 48 h), which may explain the better therapeutic efficiency and low toxicity. CONCLUSION: This novel therapeutic approach-acupoint nanocomposite hydrogel, builds a bridge between acupuncture and drugs which sheds light on the combination of traditional and modern medicine.

Prodrug polymeric micelles integrating cancer-associated fibroblasts deactivation and synergistic chemotherapy for gastric cancer.

BACKGROUND: The prognosis of patients with advanced gastric cancer (GC) remains unsatisfactory owing to distant metastasis and resistance to concurrent systemic therapy. Cancer-associated fibroblasts (CAFs), as essential participators in the tumor microenvironment (TME), play a vital role in tumor progression. Thus, CAFs-targeting therapy is appealing for remodeling TME and sensitizing GC to conventional systemic therapy. METHODS: Amphiphilic SN38 prodrug polymeric micelles (PSN38) and encapsulated the hydrophobic esterase-responsive prodrug of Triptolide (TPL), triptolide-naphthalene sulfonamide (TPL-nsa), were synthesized to form PSN38@TPL-nsa nanoparticles. Then, CAFs were isolated from fresh GC tissues and immortalized. TPL at low dose concentration was used to investigate its effect on CAFs and CAFs-induced GC cells proliferation and migration. The synergistic mechanism and antitumor efficiency of SN38 and TPL co-delivery nanoparticle were investigated both in vitro and in vivo. RESULTS: Fibroblast activation protein (FAP), a marker of CAFs, was highly expressed in GC tissues and indicated poorer prognosis. TPL significantly reduced CAFs activity and inhibited CAFs-induced proliferation, migration and chemotherapy resistance of GC cells. In addition, TPL sensitized GC cells to SN38 treatment through attenuated NF-κB activation in both CAFs and GC cells. PSN38@TPL-nsa treatment reduced the expression of collagen, FAP, and α-smooth muscle actin (α-SMA) in tumors. Potent inhibition of primary tumor growth and vigorous anti-metastasis effect were observed after systemic administration of PSN38@TPL-nsa to CAFs-rich peritoneal disseminated tumor and patient-derived xenograft (PDX) model of GC. CONCLUSION: TPL suppressed CAFs activity and CAFs-induced cell proliferation, migration and chemotherapy resistance to SN38 of GC. CAFs-targeted TPL and SN38 co-delivery nanoparticles exhibited potent efficacy of antitumor and reshaping TME, which was a promising strategy to treat advanced GC.

Sorafenib and triptolide loaded cancer cell-platelet hybrid membrane-camouflaged liquid crystalline lipid nanoparticles for the treatment of hepatocellular carcinoma.

In addition to early detection, early diagnosis, and early surgery, it is of great significance to use new strategies for the treatment of hepatocellular carcinoma (HCC). Studies showed that the combination of sorafenib (SFN) and triptolide (TPL) could reduce the clinical dose of SFN and maintain good anti-HCC effect. But the solubility of SFN and TPL in water is low and both drugs have certain toxicity. Therefore, we constructed a biomimetic nanosystem based on cancer cell-platelet (PLT) hybrid membrane camouflage to co-deliver SFN and TPL taking advantage of PLT membrane with long circulation functions and tumor cell membrane with homologous targeting. The biomimetic nanosystem, SFN and TPL loaded cancer cell-PLT hybrid membrane-camouflaged liquid crystalline lipid nanoparticles ((SFN + TPL)@CPLCNPs), could simultaneously load SFN and TPL at the molar ratio of SFN to TPL close to 10:1. (SFN + TPL)@CPLCNPs achieved long circulation function and tumor targeting at the same time, promoting tumor cell apoptosis, inhibiting tumor growth, and achieving a better "synergy and attenuation effect", which provided new ideas for the treatment of HCC.

UPLC-MS/MS method for the simultaneous quantification of pravastatin, fexofenadine, rosuvastatin, and methotrexate in a hepatic uptake model and its application to the possible drug-drug interaction study of triptolide.

A rapid and specific UPLC-MS/MS method with a total run time of 3.5 min was developed for the determination of pravastatin, fexofenadine, rosuvastatin, and methotrexate in rat primary hepatocytes. After protein precipitation with 70% acetonitrile (containing 30% H2 O), these four analytes were separated under gradient conditions with a mobile phase consisting of 0.03% acetic acid (v/v) and methanol at a flow rate of 0.50 mL/min. The linearity, recovery, matrix effect, accuracy, precision, and stability of the method were well validated. We evaluated drug-drug interactions based on these four compounds in freshly suspended hepatocytes. The hepatic uptake of pravastatin, fexofenadine, rosuvastatin, and methotrexate at 4°C was significantly lower than that at 37°C, and the hepatocytes were saturable with increased substrate concentration and culture time, suggesting that the rat primary hepatocyte model was successfully established. Triptolide showed a significant inhibitory effect on the hepatic uptake of these four compounds. In conclusion, this method was successfully employed for the quantification of pravastatin, fexofenadine, rosuvastatin, and methotrexate and was used to verify the rat primary hepatocyte model for Oatp1, Oatp2, Oatp4, and Oat2 transporter studies. Then, we applied this model to explore the effect of triptolide on these four transporters.

Effects of Multiple Doses of Dichloroacetate on GSTZ1 Expression and Activity in Liver and Extrahepatic Tissues of Young and Adult Rats.

Glutathione transferase zeta 1 (GSTZ1), expressed in liver and several extrahepatic tissues, catalyzes dechlorination of dichloroacetate (DCA) to glyoxylate. DCA inactivates GSTZ1, leading to autoinhibition of its metabolism. DCA is an investigational drug for treating several congenital and acquired disorders of mitochondrial energy metabolism, including cancer. The main adverse effect of DCA, reversible peripheral neuropathy, is more common in adults treated long-term than in children, who metabolize DCA more quickly after multiple doses. One dose of DCA to Sprague Dawley rats reduced GSTZ1 expression and activity more in liver than in extrahepatic tissues; however, the effects of multiple doses of DCA that mimic its therapeutic use have not been studied. Here, we examined the expression and activity of GSTZ1 in cytosol and mitochondria of liver, kidney, heart, and brain 24 hours after completion of 8-day oral dosing of 100 mg/kg per day sodium DCA to juvenile and adult Sprague Dawley rats. Activity was measured with DCA and with 1,2-epoxy-3-(4-nitrophenoxy)propane (EPNPP), reported to be a GSTZ1-selective substrate. In DCA-treated rats, liver retained higher expression and activity of GSTZ1 with DCA than other tissues, irrespective of rodent age. DCA-treated juvenile rats retained more GSTZ1 activity with DCA than adults. Consistent with this finding, there was less measurable DCA in tissues of juvenile than adult rats. DCA-treated rats retained activity with EPNPP, despite losing over 98% of GSTZ1 protein. These data provide insight into the differences between children and adults in DCA elimination under a therapeutic regimen and confirm that the liver contributes more to DCA metabolism than other tissues. SIGNIFICANCE STATEMENT: Dichloroacetate (DCA) is one of few drugs exhibiting higher clearance from children than adults, after repeated doses, for reasons that are unclear. We hypothesized that juveniles retain more glutathione transferase zeta 1 (GSTZ1) than adults in tissues after multiple DCA doses and found this was the case for liver and kidney, with rat as a model to assess GSTZ1 protein expression and activity with DCA. Although 1,2-epoxy-3-(4-nitrophenoxy)propane was reported to be a selective GSTZ1 substrate, its activity was not reduced in concert with GSTZ1 protein.

Dihydromyricetin affect the pharmacokinetics of triptolide in rats.

1. Dihydromyricetin (DMY) has anti-tumor and hepatoprotective activities and inhibits the activity of CYP enzymes and P-gp. In this research, we explored the effect of DMY on the pharmacokinetics of triptolide (TP), an anti-tumor Chinese medicine that is mainly metabolized by CYP enzymes and is the substrate of P-gp.2. Rats were administrated TP (1.2 mg/kg) with and without DMY in different dosage regimens, then a sensitive and reliable LC-MS/MS method was developed and applied to assess the pharmacokinetics of TP. The blood samples for TP were collected from each rat up to 120 min after administration of TP.3. When co-administrated with single dose of DMY (100 mg/kg), the AUC, Cmax and T1/2 of TP were significantly enhanced by 98, 83 and 66%, respectively. The T1/2 of TP was significantly prolonged from 23.6 ± 6.4 to 70.5 ± 12.5 min with 14-doses pretreatment of DMY (500 mg/kg), conversely, the Cmax was decreased by 30% and the AUC was enhanced by 24%.4. These results hinted that administration of DMY with TP did alter the pharmacokinetics of TP, and provided the theoretical pharmacokinetic basis to study on the protective effects of DMY against acute liver injury caused by TP.

Influence of astragaloside IV on pharmacokinetics of triptolide in rats and its potential mechanism.

Context: It is common to combine two or more drugs in clinics in China. Triptolide (TP) has been used primarily for the treatment of inflammatory and autoimmune diseases. Astragaloside IV (AS-IV) has been applied with many other drugs, due to its various pharmacological effects. AS-IV and TP can be used together for the treatment of diseases in clinics in China.Objective: This study investigates the effects of astragaloside IV (AS-IV) on the pharmacokinetics of TP in rats and its potential mechanism.Materials and methods: The pharmacokinetics of orally administered triptolide (2 mg/kg) with or without AS-IV pre-treatment (100 mg/kg/day for 7 d) were investigated. Additionally, the effects of AS-IV on the transport of triptolide were investigated using the Caco-2 cell transwell model.Results: The results indicated that when the rats were pre-treated with AS-IV, the Cmax of triptolide decreased from 418.78 ± 29.36 to 351.31 ± 38.88 ng/mL, and the AUC0-t decreased from 358.83 ± 19.56 to 252.23 ± 15.75 µg/h/L. The Caco-2 cell transwell experiments indicated that AS-IV could increase the efflux ratio of TP from 2.37 to 2.91 through inducing the activity of P-gp.Discussion and conclusions: In conclusion, AS-IV could decrease the system exposure of triptolide when they are co-administered, and it might work through decreasing the absorption of triptolide by inducing the activity of P-gp.

Quantitative in vitro-to-in vivo extrapolation (QIVIVE) of estrogenic and anti-androgenic potencies of BPA and BADGE analogues.

The goal of the present study was to obtain an in vivo relevant prioritization method for the endocrine potencies of different polycarbonate monomers, by combining in vitro bioassay data with physiologically based kinetic (PBK) modelling. PBK models were developed for a selection of monomers, including bisphenol A (BPA), two bisphenol F (BPF) isomers and four different bisphenol A diglycidyl ethers (BADGEs), using in vitro input data. With these models, the plasma concentrations of the compounds were simulated, providing means to estimate the dose levels at which the in vitro endocrine effect concentrations are reached. The results revealed that, whereas the in vitro relative potencies of different BADGEs (predominantly anti-androgenic effects) can be up to fourfold higher than BPA, the estimated in vivo potencies based on the oral equivalent doses are one to two orders of magnitude lower than BPA because of fast detoxification of the BADGEs. In contrast, the relative potencies of 2,2-BPF and 4,4-BPF increase when accounting for the in vivo availability. 4,4-BPF is estimated to be fivefold more potent than BPA in humans in vivo in inducing estrogenic effects and both 2,2-BPF and 4,4-BPF are estimated to be, respectively, 7 and 11-fold more potent in inducing anti-androgenic effects. These relative potencies were considered to be first-tier estimates, particularly given that the potential influence of intestinal metabolism on the in vivo availability was not accounted for. Overall, it can be concluded that both 2,2-BPF and 4,4-BPF are priority compounds.

Effects of triptolide on pharmacokinetics of fenofibrate in rats and its potential mechanism.

Triptolide and fenofibrate are often used together for the treatment of nephrotic syndrome in Chinese clinics. This study investigates the effects of triptolide on the pharmacokinetics of fenofibrate in rats and it potential mechanism. The pharmacokinetics of fenofibrate (20 mg/kg) with or without triptolide pretreatment (2 mg/kg/day for seven days) were investigated. Additionally, the inhibitory effects of triptolide on the metabolic stability of fenofibrate were investigated using rat liver microsome incubation systems. The results indicated that the Cmax (35.34 ± 7.52 vs. 30.43 ± 6.45 µg/mL), t1/2 (6.17 ± 1.15 vs. 4.90 ± 0.82 h) and AUC(0-t) (468.12 ± 35.84 vs. 416.35 ± 32.68 mg h L-1) of fenofibric acid decreased significantly (p < .05). The Tmax of fenofibric acid increased significantly (p < .05) from 5.12 ± 0.36 to 6.07 ± 0.68 h. Additionally, the metabolic stability of fenofibrate was prolonged from 35.8 ± 6.2 to 48.6 ± 7.5 min (p < .05) with the pretreatment of triptolide. In conclusion, these results indicated that triptolide could affect the pharmacokinetics of fenofibric acid, possibly by inhibiting the metabolism of fenofibrate in rat liver when they were co-administered.

Galactosylated chitosan triptolide nanoparticles for overcoming hepatocellular carcinoma: Enhanced therapeutic efficacy, low toxicity, and validated network regulatory mechanisms.

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related deaths worldwide. Current therapies present significant limitations. Triptolide (TP) is highly effective against multiple cancers including HCC. However, high toxicity, low water solubility, and unknown therapeutic targets limit its clinical application. Herein, we designed galactosylated-chitosan-TP-nanoparticles (GC-TP-NPs) with high drug loading capacities for targeted delivery to HCC. In addition to a sustained release pattern, an efficient asialoglycoprotein receptor mediated cellular uptake in vitro, and high liver tumor accumulation in vivo, GC-TP-NPs showed lower systemic and male reproductive toxicities than free TP. Importantly, GC-TP-NPs retained the anti-cancer activities of the free TP, exerting the same pro-apoptotic and anti-proliferative effects on HCC cells in vitro, and displayed higher efficacies in reducing tumor sizes in vivo. Further investigation revealed that GC-TP-NPs induced cancer cell apoptosis via blocking TNF/NF-κB/BCL2 signaling. Collectively, GC-TP-NP represents a promising candidate in halting liver cancer progression while minimizing systemic toxicity.

A sensitive LC-MS/MS method for the determination of triptolide and its application to pharmacokinetic research in rats.

Triptolide is one of the main active ingredients of Tripterygium wilfordii Hook. F. In this study, a sensitive LC-MS/MS method was established and validated to determine the concentration of triptolide in rat plasma. Triptolide and an internal standard [(5R)-5-hydroxytriptolide] were extracted from 100 µL of rat plasma with acetonitrile, and the dried residue was then reconstituted and reacted with benzylamine to produce benzylamine triptolide and benzylamine (5R)-5-hydroxytriptolide. Derivatization increased the sensitivity of triptolide detection by ~100-fold. Quantification was performed using a QTRAP 5500 tandem mass spectrometer with positive electrospray ionization in multiple reaction monitoring mode with an ion transition m/z 468.5 → 192.0 for benzylamine triptolide and m/z 484.3 → 192.1 for benzylamine (5R)-5-hydroxytriptolide. Good linearity was observed in the range of 0.030-100 ng/mL with a lower limit of quantitation of 0.030 ng/mL. The intra- and inter-day precision was <6.5%, and the accuracy ranged from -11.7 to -4.4%. The recovery remained consistent and was reproducible at different concentrations. This method was successfully applied to the study of triptolide drug-drug interactions in Sprague-Dawley rats. With the use of itraconazole (40 mg/kg, p.o.) as a CYP3A inhibitor, the plasma exposure of triptolide in rats was increased by 36%.

Effects of puerarin on the pharmacokinetics of triptolide in rats.

Context: Puerarin and triptolide are sometimes used together for the treatment of disease in Chinese clinics; however, the drug-drug interaction between puerarin and triptolide is still unknown. Objective: This study investigates the effects of puerarin on the pharmacokinetics of triptolide in rats and clarifies its main mechanism. Materials and methods: The pharmacokinetic profiles of oral administration of triptolide (1 mg/kg) in Sprague-Dawley rats with (test group, n = 6) or without pretreatment (control group, n = 6) with puerarin (100 mg/kg/day for seven days) were investigated. The effects of puerarin on the transport and metabolic stability of triptolide were also investigated using Caco-2 cell transwell model and rat liver microsomes. Results: The results showed that puerarin could significantly increase the peak plasma concentration (from 187.25 ± 15.36 to 219.67 ± 21.52 ng/mL), and decrease its oral clearance (from 4.92 ± 0.35 to 62.46 ± 3.75 ± 0.19 L/h/kg). The Caco-2 cell transwell experiments indicated that puerarin could decrease the efflux ratio of triptolide from 2.70 to 1.33, and the intrinsic clearance rate of triptolide was decreased by the pretreatment with puerarin (38.8 ± 4.7 vs. 32.9 ± 6.5 µL/min/mg protein). Discussion and conclusions: Puerarin could significantly change the pharmacokinetic profiles of triptolide in rats, and it might exert these effects through increasing the absorption of triptolide by inhibiting the activity of P-gp, or through inhibiting the metabolism of triptolide in rat liver. The results also showed that the dose of triptolide should be decreased when these drugs were co-administered.

[Establishment of skin and joint micro-dialysis sampling method of triptolide in vivo by HPLC-MS/MS].

To detect the concentration of triptolide in skin and joint after percutaneous administration,an HPLC-MS/MS method and skin and joint micro-dialysis( MD) method of triptolide were established in this study. The separation was achieved on triple quadrupole( AB QTRAP4500) and phenomenex-C18( 4. 6 mm×150 mm,5 µm,luna) column with acetonitrile-water with 0. 1% formic acid( 65 ∶35) as the mobile phase at a flow rate of 0. 7 m L·min-1. An electrospray ionization( ESI) source was applied and operated in the positive multiple reaction monitoring( MRM) mode. The fragment ion for triptolide was m/z 361. 1→145. 0. The effects of different perfusion [Ringer's,PBS( p H 7. 4),30% ethanol saline]drug concentrations and flow rates on the recovery rate,as well as the relationship between the recovery rate and the loss rate were determined by incremental( dialysis) and reduction( retrodialysis) methods.The reduction method was applied in the in vivo study to investigate and determine the stability of the probe recovery rate in 10 h. The results of HPLC-MS/MS detection method conformed to the requirements of biological samples. The perfusion fluid was 30% ethanol saline. The recovery rate of skin and joint probes in vitro of triptolide increased within the flow rate of 0. 5-2. 5 µL·min-1. In order to increase the timeliness of data and the accuracy,the flow rate was determined to be 1 µL·min-1,and the sample interval was determined to be 0. 5 h. The recovery rate of triptolide in skin and joint probes in vitro and the loss rate were stable and equal despite of change of triptolide concentration within 10-200 µg·L-1. This indicated that the effect of drug concentration on the MD probe recovery rate was small,and the recovery rate could be replaced by the loss rate. The loss rate in vivo using MD method was measured at 10 h,indicating that the transfer rate of triptolide was stable within 10 h. The established method of triptolide in MD and HPLC-MS/MS can be applied to investigate the kinetic in skin and joint after percutaneous administration of triptolide.

Preclinical Efficacy and Safety of the Novel Antidiabetic, Antiobesity MetAP2 Inhibitor ZGN-1061.

Methionine aminopeptidase 2 (MetAP2) inhibition is a promising approach to treating diabetes, obesity, and associated metabolic disorders. Beloranib, a MetAP2 inhibitor previously investigated for treatment of Prader-Willi syndrome, was associated with venous thrombotic adverse events likely resulting from drug effects on vascular endothelial cells (ECs). Here, we report the pharmacological characterization of ZGN-1061, a novel MetAP2 inhibitor being investigated for treatment of diabetes and obesity. Four weeks of subcutaneous administration of ZGN-1061 to diet-induced obese (DIO) insulin-resistant mice produced a 25% reduction in body weight, primarily due to reduced fat mass, that was comparable to beloranib. ZGN-1061 also produced improvements in metabolic parameters, including plasma glucose and insulin, and, in HepG2 cells, initiated gene changes similar to beloranib that support observed in vivo pharmacodynamics. In vitro studies in ECs demonstrated that ZGN-1061 effects on EC proliferation and coagulation proteins were greatly attenuated, or absent, relative to beloranib, due to lower intracellular drug concentrations, shorter half-life of inhibitor-bound MetAP2 complex, and reduced cellular enzyme inhibition. In dogs, ZGN-1061 was more rapidly absorbed and cleared, with a shorter half-life than beloranib. Unlike beloranib, ZGN-1061 did not increase coagulation markers in dogs, and ZGN-1061 had a greatly improved safety profile in rats relative to beloranib. In conclusion, ZGN-1061 and beloranib demonstrated similar efficacy in a mouse model of obesity, while ZGN-1061 had a markedly improved safety profile in multiple in vitro and in vivo models. The lower duration of exposure characteristic of ZGN-1061 is expected to provide a meaningfully enhanced clinical safety profile.

CYP3A4 inducer and inhibitor strongly affect the pharmacokinetics of triptolide and its derivative in rats.

Triptolide is the most active ingredient of Tripterygium wilfordii Hook F, which is used to treat rheumatoid arthritis. (5R)-5-Hydroxytriptolide is a hydroxylation derivative of triptolide with a reduced toxicity. To investigate the metabolic enzymes of the two compounds and the drug-drug interactions with enzyme inducers or inhibitors, a series of in vitro and in vivo experiments were conducted. In vitro studies using recombinant human cytochrome P450 enzyme demonstrated that cytochrome P450 3A4 (CYP3A4) was predominant in the metabolism of triptolide and (5R)-5-hydroxytriptolide, accounting for 94.2% and 64.2% of the metabolism, respectively. Pharmacokinetics studies were conducted in male SD rats following administration of triptolide or (5R)-5-hydroxytriptolide (0.4 mg/kg, po). The plasma exposure to triptolide and (5R)-5-hydroxytriptolide in the rats was significantly increased when co-administered with the CYP3a inhibitor ritonavir (30 mg/kg, po) with the values of AUC0-∞ (area under the plasma concentration-time curve from time zero extrapolated to infinity) being increased by 6.84 and 1.83 times, respectively. When pretreated with the CYP3a inducer dexamethasone (50 mg·kg-1·d-1, for 3 d), the AUC0-∞ values of triptolide and (5R)-5-hydroxytriptolide were decreased by 85.4% and 91.4%, respectively. These results suggest that both triptolide and (5R)-5-hydroxytriptolide are sensitive substrates of CYP3a. Because of their narrow therapeutic windows, clinical drug-drug interaction studies should be carried out to ensure their clinical medication safety and efficacy.

Lipid nanoparticles loading triptolide for transdermal delivery: mechanisms of penetration enhancement and transport properties.

BACKGROUND: In recent years, nanoparticles (NPs) including nanostructured lipid carries (NLC) and solid lipid nanoparticles (SLN) captured an increasing amount of attention in the field of transdermal drug delivery system. However, the mechanisms of penetration enhancement and transdermal transport properties of NPs are not fully understood. Therefore, this work applied different platforms to evaluate the interactions between skin and NPs loading triptolide (TPL, TPL-NLC and TPL-SLN). Besides, NPs labeled with fluorescence probe were tracked after administration to investigate the dynamic penetration process in skin and skin cells. In addition, ELISA assay was applied to verify the in vitro anti-inflammatory effect of TPL-NPs. RESULTS: Compared with the control group, TPL-NPs could disorder skin structure, increase keratin enthalpy and reduce the SC infrared absorption peak area. Besides, the work found that NPs labeled with fluorescence probe accumulated in hair follicles and distributed throughout the skin after 1 h of administration and were taken into HaCaT cells cytoplasm by transcytosis. Additionally, TPL-NLC could effectively inhibit the expression of IL-4, IL-6, IL-8, IFN-γ, and MCP-1 in HaCaT cells, while TPL-SLN and TPL solution can only inhibit the expression of IL-6. CONCLUSIONS: TPL-NLC and TPL-SLN could penetrate into skin in a time-dependent manner and the penetration is done by changing the structure, thermodynamic properties and components of the SC. Furthermore, the significant anti-inflammatory effect of TPL-NPs indicated that nanoparticles containing NLC and SLN could serve as safe prospective agents for transdermal drug delivery system.

Influence of grapefruit juice on pharmacokinetics of triptolide in rats grapefruit juice on the effects of triptolide.

1. Triptolide, a major pharmacological component isolated from Tripterygium wilfordii Hook F (TWHF), is a substrate of both CYP3A4 and P-glycoprotein (P-gp). 2. This study investigates the effects of GFJ on the pharmacokinetics of triptolide in rats. 3. The pharmacokinetics of orally administered triptolide with or without GFJ pretreatment were investigated. A mechanistic study was also undertaken using the Caco-2 cell transwell model and rat liver microsomes incubation systems to support the in vivo pharmacokinetic data. 4. The results indicated that coadministration of GFJ could increase the systemic exposure of triptolide significantly, including area under the curve (828.58 ± 79.72 versus 541.53 ± 45.23 ng·h/mL) and maximum plasma concentration (273.58 ± 27.98 versus 193.67 ± 10.08 ng/mL). The apparent permeability of triptolide across the Caco-2 cell transwell model increased significantly with the pretreatment of GFJ (from 1.62 ± 0.25 × 10-6 to 2.51 ± 0.41 × 10-6 cm/s), and the metabolic stability of triptolide was also increased from 32.6 ± 5.1 to 52.5 ± 7.8 min with the pretreatment of GFJ, and the difference was significant (p < 0.05). 5. In conclusion, GFJ could increase the systemic exposure of triptolide in rats, when GFJ and triptolide was coadministered, and it might work mainly through increasing the absorption of triptolide by inhibiting P-gp, or through slowing down the metabolism of triptolide in rat liver by inhibiting the activity of CYP3A4.

Compatibility with Panax notoginseng and Rehmannia glutinosa Alleviates the Hepatotoxicity and Nephrotoxicity of Tripterygium wilfordii via Modulating the Pharmacokinetics of Triptolide.

Tripterygium wilfordii (TW) and the representative active component triptolide show positive therapeutic effect on the autoimmune disorders and simultaneously ineluctable hepatotoxicity and nephrotoxicity. Combinational application of Panax notoginseng (PN) and Rehmannia glutinosa (RG) weakens the toxicity of TW according the clinical application of traditional Chinese medicine. This article was aimed at the mechanism of decreasing toxicity of TW by the combinational application of PN and RG. Biochemical and pathohistological analysis were utilized to assess the toxicity on liver and kidney in rats administrated with TW, TW-PN, TW-RG and TW-PN-RG for 3 and 7 days. Meanwhile, the pharmacokinetics profiling of triptolide and wilforlide A was determined based on the plasma concentration analyzed by ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). TW-induced alkaline phosphatase (ALP), the marker for liver injury, was enhanced from 22.83 ± 1.29 to 40.73 ± 1.42 King's unit/100 mL (p < 0.01) at day 7. TW-PN-RG decreased the serum ALP of TW-treated rats at 30.15 ± 1.27 King's unit/100 mL (p < 0.01). For nephrotoxicity, TW pronouncedly elevated serum creatinine (SCr) in rats from 20.33 ± 1.77 to 49.82 ± 2.35 µmol/L (p < 0.01). However, rats treated with TW-PN-RG showed lower SCr at 30.48 ± 1.98 µmol/L (p < 0.01). Moreover, TW-PN-RG significantly decreased the TW-induced elevation of total bilirubin (T-BIL), alanine amino transferase (ALT), aspartate amino transferase (AST), blood urea nitrogen (Bun), and reversed the TW-resulted pathohistological characteristics of liver and kidney. The delayed time to reach Cmax (Tmax) and reduced maximum concentration (Cmax) and area under plasma concentration-time curve (AUC) of triptolide and wilforlide A were explored in rats with combinational formulas. Synergism of PN and RG obviously prolonged the half-life (t1/2) and apparent volume of distribution (Vd), but exerted no action on the clearance rate. The compatibility of TW, PN and RG influences intracorporal process of both triptolide and wilforlide A on the steps of absorption and tissue distribution contributing to less toxicity of TW on liver and kidney.

Effects of triptolide on pharmacokinetics of amlodipine in rats by using LC-MS/MS.

CONTEXT: Triptolide and amlodipine are often simultaneously used for reducing urine protein excretion after renal transplantation in China clinics. OBJECTIVE: This study investigated the effects of triptolide on the pharmacokinetics of amlodipine in male Sprague-Dawley rats. MATERIALS AND METHODS: The pharmacokinetics of amlodipine (1 mg/kg) with or without triptolide pre-treatment (2 mg/kg/day for seven days) were investigated using a sensitive and reliable LC-MS/MS method. Additionally, the inhibitory effects of triptolide on the metabolic stability of amlodipine were investigated using rat liver microsome incubation systems. RESULTS: The results indicated that when the rats were pre-treated with triptolide, the Cmax of amlodipine increased from 13.78 ± 3.57 to 19.96 ± 4.56 ng/mL (p < 0.05), the Tmax increased from 4.04 ± 1.15 to 5.89 ± 1.64 h (p < 0.05), and the AUC0-t increased by approximately 104% (p < 0.05), which suggested that the pharmacokinetic behaviour of amlodipine was affected after oral co-administration of triptolide. Additionally, the metabolic half-life was prolonged from 22.5 ± 4.26 to 36.8 ± 6.37 min (p < 0.05) with the pre-treatment of triptolide. CONCLUSIONS: In conclusion, these results indicated that triptolide could affect the pharmacokinetics of amlodipine, possibly by inhibiting the metabolism of amlodipine in rat liver when they are co-administered.

Development of triptolide-nanoemulsion gels for percutaneous administration: physicochemical, transport, pharmacokinetic and pharmacodynamic characteristics.

BACKGROUND: This work aimed to provide useful information on the use of nanoemulsions for the percutaneous administration of triptolide. Lipid nanosystems have great potential for transdermal drug delivery. Nanoemulsions and nanoemulsion gels were prepared to enhance percutaneous permeation. Microstructure and in vitro/in vivo percutaneous delivery characteristics of triptolide (TPL)-nanoemulsions and TPL-nanoemulsion gels were compared. The integrity of the nanoemulsions and nanoemulsion gels during transdermal delivery and its effects on the surface of skin were also investigated. The penetration mechanisms of nanoemulsions and nanoemulsion gels were investigated by differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR). The transport characteristics of fluorescence-labelled nanoemulsions were probed using laser scanning confocal microscopy. A chronic dermatitis/eczema model in mice ears and the pharmacodynamic of the TPL-nanoemulsion gels were also investigated. RESULTS: Compared to TPL gels, significantly greater cumulative amounts of TPL-nanoemulsion gels and TPL-nanoemulsions penetrated rat skin in vitro. The in vivo microdialysis showed the concentration-time curve AUC0-t for TPL-NPs is bigger than the TPL-gels. At the same time, TPL-NPs had a larger effect on the surface of skin. By hydrating keratin and changing the structure of both the stratum corneum lipids and keratin, nanoemulsions and nanoemulsion gels influence skin to promote percutaneous drug penetration. Both hairfollicles and the stratum corneum are also important in this transdermal drug delivery system. Moderate and high dosages of the TPL-nanoemulsion gels can significantly improve the symptoms of dermatitis/eczema inflammation and edema erythematic in mice ears and can reduce the expression of IFN-γ and IL-4. Moreover, the TPL-nanoemulsion gels cause less gastrointestinal damage than that of the Tripterygium wilfordii oral tablet does. CONCLUSIONS: Nanoemulsions could be suitable for transdermal stably releasing drugs and maintaining the effective drug concentration. The TPL-nanoemulsion gels provided higher percutaneous amounts than other carriers did. These findings suggest that nanoemulsion gels could be promising percutaneous carriers for TPL. The TPL-nanoemulsion gels have a significant treatment effect on dermatitis/eczema in the mice model and is expected to provide a new, low-toxicity and long-term preparation for the clinical treatment of dermatitis/eczema in transdermal drug delivery systems.