Toxicity Of Triptolide Research Articles

Glycyrrhizic acid rebalances mitochondrial dynamics to mitigate hepatotoxicity induced by triptolide

Triptolide (TP) has various pharmacological activities, but its hepatotoxicity limits its therapeutic potential. Licorice has been evaluated to harmonize various medicines, and its active ingredient glycyrrhizic acid (GA) has been identified for its detoxification effect. In this study, we demonstrated that the combination of GA and TP (G&T) could mitigate TP-induced hepatotoxicity. To explore TP toxicity and G&T detoxification mechanisms, transcriptomics and proteomics have been utilized. TP was found to promote the expression of PKCα and FIS1, accompanied by an increase in mitochondrial fission. After pretreatment with GA, improvements were observed in TP-induced mitochondrial fission, as well as the expression of active-caspase3, and cytochrome c release. Silencing PKCα and FIS1 has a similar effect to GA on the regulation of mitochondria-dependent apoptosis and mitochondrial fission. In conclusion, PKCα and FIS1-involved mitochondrial dynamic regulation is associated with TP-induced hepatotoxicity. The G&T combination may be an effective strategy for ameliorating TP-induced toxicity.

Triptolide induces PANoptosis in macrophages and causes organ injury in mice.

Macrophages represent the first lines of innate defense against pathogenic infections and are poised to undergo multiple forms of regulated cell death (RCD) upon infections or toxic stimuli, leading to multiple organ injury. Triptolide, an active compound isolated from Tripterygium wilfordii Hook F., possesses various pharmacological activities including anti-tumor and anti-inflammatory effects, but its applications have been hampered by toxic adverse effects. It remains unknown whether and how triptolide induces different forms of RCD in macrophages. In this study, we showed that triptolide exhibited significant cytotoxicity on cultured macrophages in vitro, which was associated with multiple forms of lytic cell death that could not be fully suppressed by any one specific inhibitor for a single form of RCD. Consistently, triptolide induced the simultaneous activation of pyroptotic, apoptotic and necroptotic hallmarks, which was accompanied by the co-localization of ASC specks respectively with RIPK3 or caspase-8 as well as their interaction with each other, indicating the formation of PANoptosome and thus the induction of PANoptosis. Triptolide-induced PANoptosis was associated with mitochondrial dysfunction and ROS production. PANoptosis was also induced by triptolide in mouse peritoneal macrophages in vivo. Furthermore, triptolide caused kidney and liver injury, which was associated with systemic inflammatory responses and the activation of hallmarks for PANoptosis in vivo. Collectively, our data reveal that triptolide induces PANoptosis in macrophages in vitro and exhibits nephrotoxicity and hepatotoxicity associated with induction of PANoptosis in vivo, suggesting a new avenue to alleviate triptolide's toxicity by harnessing PANoptosis.

Insights into the mechanisms of triptolide nephrotoxicity through network pharmacology-based analysis and RNA-seq.

Triptolide (TPL) is a promising plant-derived compound for clinical therapy of multiple human diseases; however, its application was limited considering its toxicity. To explore the underlying molecular mechanism of TPL nephrotoxicity, a network pharmacology based approach was utilized to predict candidate targets related with TPL toxicity, followed by deep RNA-seq analysis to characterize the features of three transcriptional elements include protein coding genes (PCGs), long noncoding RNAs (lncRNAs) and circular RNAs (circRNAs) as well as their associations with nephrotoxicity in rats with TPL treatment. Although the deeper mechanisms of TPL nephrotoxcity remain further exploration, our results suggested that c-Jun is a potential target of TPL and Per1 related circadian rhythm signaling is involved in TPL induced renal toxicity.

Targeted delivery of triptolide by dendritic cell-derived exosomes for colitis and rheumatoid arthritis therapy in murine models.

Triptolide (TP) elicits a beneficial effect in the treatment of autoimmune diseases, such as ulcerative colitis (UC) and rheumatoid arthritis (RA). However, its multiorgan toxicity needs to be resolved. Dendritic cells (DCs) are the primary target of TP, which induces immunosuppression, and DC-derived exosomes (DEX) can selectively enter DCs in vivo. Here, we encapsulated TP with DEX (DEXTP) to generate TP-targeted delivery to reduce toxicity. The effect of DEXTP was evaluated in murine colitis and RA models. Toxicity was examined by haematoxylin and eosin staining and serum biochemical marker detection. Affinity of DEXs for DCs was tracked by fluorescent labelling. The immune environment was evaluated and mimicked in vitro for further analysis of the mechanism. DEXTP effectively carried TP to DCs in vivo, and alleviated local inflammation and damage in colitis and RA mice with no obvious toxicity. Additionally, DEXTP reshaped the immune milieu by decreasing CD4+ T-cell levels and increasing regulatory T-cell levels in vivo. Furthermore, consistent T-cell differentiation was observed in vitro, and DC activation was inhibited by alterations in surface factors and secrete cytokines, and by induction of apoptosis or other form of death. Encapsulating TP with DEX is a new method that both reduces the toxicity of TP and induces immunosuppression in UC and RA mice. The underlying immune mechanism involves DEXTP targeting DCs in vivo, to inhibit DC activation and induce DC apoptosis, which further induces T-cell immunosuppression.

Triptolide and l-ascorbate palmitate co-loaded micelles for combination therapy of rheumatoid arthritis and side effect attenuation

Triptolide (TP) has its unique curative effect in the treatment of rheumatoid arthritis (RA), but its application is limited by the poor water solubility and multi-organ toxicity. We herein developed a novel nanoparticle platform composed of L-ascorbate palmitate (VP, vitamin C derivative) that can deliver TP to synergistically treat arthritis and inhibit the occurrence of oxidative stress. The TP-loaded nanoparticles (termed TP-VP NPs) showed the suitable particle size (about 145 nm) and good physical stability. TP-VP NPs effectively down-regulated IL-1β, IL-6 and TNF-α levels to inhibit the erosion of synovitis and bone tissue, and alleviate the swelling and deformation of CIA mice’s feet. Compared to the TP, TP-VP NPs could inhibit effectively the oxidative stress in liver, and alleviate significantly the triptolide-induced toxicity injury in liver, kidney and testicle. The results demonstrated that TP-VP NPs is a promising triptolide delivery system for the treatment of RA, which enhances the water solubility of TP and reduces the toxicity of TP in vivo.

Pharmacokinetics and Tissue Distribution of Combined Triptolide and Paeoniflorin Regimen for Percutaneous Administration in Rats Assessed by Liquid Chromatography-Tandem Mass Spectrometry.

Triptolide (TP) has shown potential in rheumatoid arthritis (RA) treatment, but the narrow therapeutic window limits its clinical application. In clinical practice, the compatibility of Tripterygium wilfordii and Paeonia lactiflora is often used to attenuate the toxicity of TP, but its compatibility mechanism has not been fully elucidated. The aim of this study was to investigate the pharmacokinetics and tissue distribution of a combined regimen of TP and paeoniflorin (PF) after transdermal administration in male and female Sprague Dawley (SD) rats via a rapid and sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. The results showed that after percutaneous administration of TP and PF, there was no significant difference in AUC (0-t) (area under the curve) of TP, the peak concentration decreased by 58.17%, and the peak time was delayed. The AUC (0-t) of PF increased significantly (P < 0.01), the peak-reaching concentration and AUC (0-∞) increased, and the half-life and average retention time were shortened, indicating that TP absorption in rats may be delayed. After percutaneous administration of TP and PF, the content of TP in the heart, liver, spleen, lungs, and kidneys of male rats significantly decreased at 2 h (P < 0.05) and the drug concentration in the liver tissues significantly decreased at 2 h, 4 h, and 8 h (P < 0.05). The TP content in the spleen of female rats significantly decreased at 2 h and 4 h (P < 0.05) and also decreased in other tissues, but not significantly. After percutaneous administration of TP and PF, the PF content in the heart, liver, spleen, lungs, and kidneys of male and female rats had no significant difference. However, after percutaneous administration of TP and PF, the TP concentration in the skin increased, suggesting that the amount of TP retained in the skin increased, thereby reducing its content in blood and tissues, producing a reduction in toxicity effect.

Anti-Alzheimer’s disease performance of triptolide nanoliposomes modified with lactoferrin

According to the immune inflammation theory of Alzheimer’s disease (AD), triptolide (TP) is a potential drug for the treatment of AD, but it distributed widely in vivo resulting in the multi-organ toxicity. In order to improve the efficacy and reduce the toxicity of TP, stealth brain-targeting TP nanoliposomes (Lf-TP-PL) were prepared with polyethyleneglycol (PEG)-modified and lactoferrin (Lf) as the brain-targeting head group. Compared with TP solution (TP-S), common TP nanoliposomes (TP-CL) and PEG-modified TP nanoliposomes (TP-PL), the effect of Lf-TP-PL on the growth of PC12 cells inductively damaged by Aβ1-42, as the model in vitro AD cells, was studied. The effects of Lf-TP-PL on the behavioral ability of AD model mice were evaluated by Morris water maze test. The results showed that compared with TP-S, TP-CL, and TP-PL, Lf-TP-PL had stronger abilities to repair the PC12 cells inductively damaged by Aβ1-42, and could mitigate spatial memory deficit of AD model mice in a better way. Lf-TP-PL is a potential nanomedicine for AD treatment.

Triptolide and atorvastatin synergistically promote hepatotoxicity in cultured hepatocytes and female Sprague-Dawley rats by inhibiting pregnane X receptor-mediated transcriptional activation of CYP3A4

Triptolide (TP), an active component of Tripterygium wilfordii Hook. F, has been widely used in China for treating autoimmune and inflammatory diseases, and has also been validated by modern science and developed as a candidate anti-cancer treatment. However, liver toxicity of TP has seriously hindered its use and development, the clinical features and primary toxicological mechanism have been unclear. Considering the major target regulation mechanism of TP is the suppression of global transcription regulated by RNAPII, which is closed related with the detoxification of drugs. This paper tries to verify the synergistic liver injury and its mechanism of TP when co-administered with CYP3A4 substrate drug. The experiments showed that TP dose-dependently blocked transcriptional activation of CYP3A4 in both hPXR and hPXR-CYP3A4 reporter cell lines, lowered the mRNA and protein expression of PXR target genes such as CYP3A1, CYP2B1, and MDR1, and inhibited the functional activity of CYP3A in a time- and concentration-dependent manner in sandwich-cultured rat hepatocytes (SCRH) and female Sprague-Dawley (f-SD) rats. Furthermore, TP combined with atorvastatin (ATR), the substrate of CYP3A4, synergistically enhanced hepatotoxicity in cultured HepG2 and SCRH cells (CI is 0.38 and 0.29, respectively), as well as in f-SD rats, with higher exposure levels of both drugs. These results clearly indicate that TP inhibits PXR-mediated transcriptional activation of CYP3A4, leading to a blockade on the detoxification of itself and ATR, thereby greatly promoting liver injury. This study may implies the key cause of TP related liver injury and provides experimental data for the rational use of TP in a clinical scenario.

Construction of a pH-responsive, ultralow-dose triptolide nanomedicine for safe rheumatoid arthritis therapy

Rheumatoid arthritis (RA) is a chronicautoimmune disease, marked by joint swelling and pain, articular synovial hyperplasia, as well as cartilage and bone destruction. Triptolide (TP) is an anti-inflammatory molecule but its use to treat RA is limited due to poor solubility and extremely high toxicity. In this study, by encapsulating TP into a star-shaped amphiphilic block copolymer, POSS-PCL-b-PDMAEMA, we engineered a pH-sensitive TP-loaded nanomedicine (TP@NPs) to simultaneously reduce the toxicity of TP and improve its therapeutic efficacy. TP@NPs shows a uniform spherical structure with a hydrodynamic diameter of ~92 nm and notable pH-responsiveness. In vitro TP@NPs showed reduced cytotoxicity and cell apoptosis of treated RAW264.7 cells compared to free TP. And in vivo intravenous injection of indocyanine green-labeled NPs into a collagen-induced arthritis model in mice showed that the engineered compound had potent pharmacokinetic and pharmacodynamic profiles, while exhibiting significant cartilage-protective and anti-inflammatory effects with a better efficacy and neglible systemic toxicity even at an ultralow dose compared to free TP. These results suggest that TP@NPs may be a safe and effective therapy for RA and other autoimmune diseases.

Cetuximab-Triptolide Conjugate Suppresses the Growth of EGFR-Overexpressing Lung Cancers through Targeting RNA Polymerase II

To overcome poor pharmacokinetics and toxicity of triptolide (TPL), a natural compound that exhibits potent anticancer activities, we developed a novel antibody-drug conjugate (ADC) to specifically deliver TPL to epidermal growth factor receptor (EGFR)-overexpressing non-small cell lung cancer (NSCLC) and others. The ADC (Cet-TPL) is made by conjugation of TPL to lysine residues of cetuximab (Cet), a clinically available anti-EGFR monoclonal antibody. Studies of antitumor efficacy demonstrated that Cet-TPL drastically suppressed in vitro proliferation and in vivo growth of these EGFR-overexpressing cancers, including NSCLC A549 and H1299 cells and two patient-derived xenografts, and head and neck squamous carcinoma UM-SCC6 cell, while it did not inhibit the proliferation and growth of NSCLC H520 that rarely expresses EGFR. Furthermore, immunofluorescence analysis revealed that Cet-TPL was effectively internalized and transported into lysosomes of EGFR-overexpressing cells. Cet-TPL effectively led to degradation of RNA polymerase II (Pol II) and demethylation of histone H3 lysines, and significantly induced apoptosis in these EGFR-overexpressing cancers. Compared with TPL, Cet, or their combination, Cet-TPL displayed higher target-specific cytotoxicity against EGFR-expressing cancers and much lower in vivo toxicity. In addition, Cet-TPL efficiently suppressed the activated EGFR pathway in UM-SCC6 cancer cells. Taken together, Cet-TPL represents a potent targeting therapeutic agent against EGFR-overexpressing NSCLC and others.

Triptolide impairs genome integrity by directly blocking the enzymatic activity of DNA-PKcs in human cells

Triptolide is a multi-functional natural small molecular compound extracted from a traditional Chinese medicinal herb. Triptolide and its derivatives exhibit cytotoxicity through inducing DNA damage, therefore increasing sensitivity to DNA-damage based chemotherapy or radiotherapy in different types of cells. However, the regulatory mechanism of genotoxicity by triptolide, and the loss of genome integrity induced by triptolide are not fully understood. Here, we measured the effects of triptolide on genome integrity in a human fibroblast line HCA2-hTERT using the neutral comet assay. We demonstrated that treating cells with triptolide induced genomic instability in HCA2-hTERT cells. Furthermore, we observed the accumulation of γH2AX foci in triptolide treated cells than control cells at 24 h post ionizing radiation. Further mechanistic studies indicated that triptolide inhibited the enzymatic activity of DNA-PKcs, the critical nonhomologous end joining factor. In vitro kinase activity assays showed that triptolide suppressed the kinase activity of DNA-PKcs and molecular docking also predicted a potential interaction between triptolide and DNA-PKcs. As a consequence, we found that triptolide treatment enhanced the interaction between DNA-PKcs and KU80 and hampered the following recruitment of 53BP1. Altogether, our finding provides a new perspective about the toxicity of triptolide in non-cancer cells and highlights the necessity of taking genome effects of triptolide and its derivatives into consideration in the future clinical and research applications.

Efficient Delivery of Triptolide Plus a miR-30-5p Inhibitor Through the Use of Near Infrared Laser Responsive or CADY Modified MSNs for Efficacy in Rheumatoid Arthritis Therapeutics.

Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disease for which treatment focuses on suppressing an overactive immune system and maintaining the physiological balance of synovial fibroblasts (SFs). We found that miR-30-5p was highly expressed in rheumatoid arthritis synovial fibroblasts (RASFs). Subsequently, we predicted that phosphatidylinositol 3-kinase regulatory subunit 2 (PIK3R2) might be a putative target of miR-30-5p. Recent studies have reported that PIK3R2 can maintain the physiological homeostasis of RASFs. Therefore, miR-30-5p inhibitor has the potential to be used in the treatment of RA, but low levels of miR-30-5p inhibitor internalization affect its application. Triptolide (TP) is an effective drug in the treatment of RA but induces severe toxicity and has a narrow therapeutic window. In this study, the cell internalization performance of miR-30-5p inhibitor was improved by loading it into cell membrane penetrating peptide (CADY)-modified mesoporous silica nanoparticles (MSNs), and the toxicity of TP was decreased by loading it into a controlled drug release system based on MSNs. The nanodrug carrier was constructed by filling a phase-change material (PCM) of 1-tetradecanol and drugs into MSNs that could be triggered by an NIR laser with thermo-chemo combination RA therapy. Our results show that the miR-30-5p inhibitor-loaded MSNs@CADY significantly inhibited RASF proliferation and increased apoptosis. In addition, MSNs@PCM@TP under 808 nm laser irradiation were effective in downregulating immune system activation in an RA rat model. Finally, the results of a pharmacodynamics study showed that the combination of MSNs@CADY@miR-30-5p inhibitor and MSNs@PCM@TP under 808 nm laser significantly increased the effectiveness of RA treatment. These findings provide a novel understanding of RA pathogenesis and a theoretical basis for RA treatment.

Toxic effects of triptolide on adrenal steroidogenesis in H295R cells and female rats.

Triptolide (TP), a major active ingredient of Tripterygium wilfordii, exerts potent immunosuppressive effects in the treatment of rheumatoid arthritis but is not widely used in clinical practice due to its multiorgan toxicity, particularly hepatotoxicity, nephrotoxicity, and reproductive toxicity. An LC-MS/MS approach was employed to explore the endocrine-disrupting effects of TP. The endocrine-disrupting effects of various concentrations (0-100 nM) of TP for 48 hour were firstly investigated using an in vitro model (H295R cell line). It was found that TP did not decrease cell viability. The transcriptional levels of steroidogenic enzymes in H295R cells were assessed by quantificational real-time polymerase chain reaction. The possible adrenal and endocrine effects of oral administration of TP (0, 50, and 500 μg/kg) for 28 days on both normal and collagen-induced arthritis (CIA) rats were also explored. The serum and adrenal tissue hormone levels (corticosterone and progesterone) and adrenal histopathology were analyzed, with the results that TP significantly decreased the level of cortisol in H295R cells and the level of plasma corticosterone in both normal and CIA rats. Histological alterations in adrenal cortex were observed at the dose of 500 μg/kg. Exposure to TP for 48 hour had an obvious inhibitory effect on the messenger RNA transcript levels of HSD3B2, CYP21A2, CYP17A1, and CYP11B1, which is essential for the synthesis of corticosteroids. In a word, TP leads to the disorder of corticosteroid synthesis and secretion, and corticosteroid may be a potential biomarker for the treatment of multiorgan toxicity of TP.

Differential toxicities of triptolide to immortalized podocytes and the podocytes in vivo

Triptolide (TP) has an anti-proteinuric effect and is used for the treatment of podocytopathies. TP has also been shown to act directly on immortalized podocytes in culture to protect them from injury. In the present study, we examined the effect of TP on healthy podocytes both in vitro and in vivo to better understand the action of TP on podocytes. We found that treatment of TP at 10 ng/ml, a concentration that is routinely used for podocyte protection, was sufficient to activate pro-apoptotic signaling of MAPK p38, p53 and BAX and induced apoptosis in cultured podocytes; and higher concentrations of TP exacerbated the p38, p53 and BAX activations and apoptosis. Moreover, TP severely downregulated the genes that are essential for podocyte structure and function. Interestingly, in contrast with other agents TP-induced podocyte injury was not prevented by glucocorticoids. In vivo, high-dose TP treatment for prolonged time did not cause podocyte injury, essential genes downregulation, and proteinuria in mice. TP was also not toxic to the podocytes with isolated glomeruli ex vivo. In summary, TP is toxic to immortalized podocytes in culture but not to the podocytes in animals or isolated glomeruli ex vivo. Our study suggests that immortalized podocytes might have genetically evolved to become sensitive to TP toxicity and thus caution should be taken in interpreting data from immortalized podocytes. Nevertheless, in vivo TP could be as safe as glucocorticoids in treating podocytopathies. Finally, TP may be used as a unique in vitro model for studying steroid-resistant podocytopathies.

Fabrication of a triptolide-loaded and poly-γ-glutamic acid-based amphiphilic nanoparticle for the treatment of rheumatoid arthritis.

Triptolide (TP) exhibits immunosuppressive, cartilage-protective and anti-inflammatory effects in rheumatoid arthritis. However, the toxicity of TP limits its widespread use. To decrease the toxic effects, we developed a novel nano-drug carrier system containing TP using poly-γ-glutamic acid-grafted di-tert-butyl L-aspartate hydrochloride (PAT). PAT had an average diameter of 79±18 nm, a narrow polydispersity index (0.18), a strong zeta potential (−32 mV) and a high drug encapsulation efficiency (EE1=48.6%) and loading capacity (EE2=19.2%), and exhibited controlled release (t1/2=29 h). The MTT assay and flow cytometry results indicated that PAT could decrease toxicity and apoptosis induced by free TP on RAW264.7 cells. PAT decreased lipopolysaccharides/interferon γ-induced cytokines expression of macrophage (P<0.05). In vivo, PAT accumulated at inflammatory joints, improved the survival rate and had fewer side effects on tumor necrosis factor α transgenic mice, compared to TP. The blood biochemical indexes revealed that PAT did not cause much damage to the kidney (urea nitrogen and creatinine) and liver (alanine aminotransferase and aspartate aminotransferase). In addition, PAT reduced inflammatory synovial tissue area (P<0.05), cartilage loss (P<0.05), tartrate-resistant acid phosphatase-positive osteoclast area (P<0.05) and bone erosion (P<0.05) in both knee and ankle joints, and showed similar beneficial effect as free TP. In summary, our newly formed nanoparticle, PAT, can reduce the toxicity and guarantee the efficacy of TP, which represents an effective drug candidate for RA with low adverse side effect.

The Effect of Triptolide in Rheumatoid Arthritis: From Basic Research towards Clinical Translation

Triptolide (TP), a major extract of the herb Tripterygium wilfordii Hook F (TWHF), has been shown to exert potent pharmacological effects, especially an immunosuppressive effect in the treatment of rheumatoid arthritis (RA). However, its multiorgan toxicity prevents it from being widely used in clinical practice. Recently, several attempts are being performed to reduce TP toxicity. In this review, recent progress in the use of TP for RA, including its pharmacological effects and toxicity, is summarized. Meanwhile, strategies relying on chemical structural modifications, innovative delivery systems, and drug combinations to alleviate the disadvantages of TP are also reviewed. Furthermore, we also discuss the challenges and perspectives in their clinical translation.

Quantitative Proteomics and Targeted Fatty Acids Analysis Reveal the Damage of Triptolide in Liver and Kidney.

Triptolide (TP), the major active component in Tripterygium wilfordii Hook. f., is widely used for the treatment of rheumatoid arthritis and autoimmune diseases. However, organ toxicity, especially hepatotoxicity and nephrotoxicity, limits its clinical application. To fully understand the mechanism underlying TP toxicity, iTRAQ-based 2D-LC-MS/MS proteomics is used to detect differentially expressed proteins in the livers and kidneys of mice administered the LD50 dose of TP. Functional annotation revealed that multiple pathways are involved in TP toxicity, including acute-phase response signaling, the antigen presentation pathway, FXR/RXR activation, LPS/IL-1-mediated inhibition of RXR function, and EIF2 signaling.Members of the cytochromeP450 protein family that are involved in fatty acid (FA) metabolism, such as CYP2E1, show significant differences in expression among groups. Additionally, the proteomics data suggested that FAs are involved in TP-induced toxicity. FA analysis is conducted using HPLC-MRM to characterize the differences among various groups exposed to TP for different times. It has been found that 20 FAs in the liver show significant differences in abundance among groups, whereas in the kidneys, six FAs show significant differences in abundance. By integrating the proteomic and targeted FA analyses, it has been found that differently expressed proteins and FAs both participate in pathways including cellular lipolytic activity, peroxisomal fatty acid beta-oxidation, and so on. Our data contribute to understanding the mechanisms underlying TP-induced organ toxicity. The results may help to improve the clinical efficacy and safety of TP in the future.

WITHDRAWN: Toxicity of triptolide and the molecular mechanisms involved

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UPLC/ESI-QTOF-MS-based metabolomics survey on the toxicity of triptolide and detoxication of licorice

Triptolide (TP) from Tripterygium wilfordii has been demonstrated to possess anti-inflammatory, immunosuppressive, and anticancer activities. TP is specially used for the treatment of awkward rheumatoid arthritis, but its clinical application is confined by intense side effects. It is reported that licorice can obviously reduce the toxicity of TP, but the detailed mechanisms involved have not been comprehensively investigated. The current study aimed to explore metabolomics characteristics of the toxic reaction induced by TP and the intervention effect of licorice water extraction (LWE) against such toxicity. Obtained urine samples from control, TP and TP + LWE treated rats were analyzed by UPLC/ESI-QTOF-MS. The metabolic profiles of the control and the TP group were well differentiated by the principal component analysis and orthogonal partial least squares-discriminant analysis. The toxicity of TP was demonstrated to be evolving along with the exposure time of TP. Eight potential biomarkers related to TP toxicity were successfully identified in urine samples. Furthermore, LWE treatment could attenuate the change in six of the eight identified biomarkers. Functional pathway analysis revealed that the alterations in these metabolites were associated with tryptophan, pantothenic acid, and porphyrin metabolism. Therefore, it was concluded that LWE demonstrated interventional effects on TP toxicity through regulation of tryptophan, pantothenic acid, and porphyrin metabolism pathways, which provided novel insights into the possible mechanisms of TP toxicity as well as the potential therapeutic effects of LWE against such toxicity.

Fabrication of novel vesicles of triptolide for antirheumatoid activity with reduced toxicity in vitro and in vivo.

Triptolide (TP) displays a strong immunosuppression function in immune-mediated diseases, especially in the treatment of rheumatoid arthritis. However, in addition to its medical and health-related functions, TP also exhibits diverse pharmacological side effects, for instance, liver and kidney toxicity and myelosuppression. In order to reduce the side effects, a nano drug carrier system (γ-PGA-l-PAE-TP [PPT]), in which TP was loaded by a poly-γ-glutamic acid-grafted l-phenylalanine ethylester copolymer, was developed. PPT was characterized by photon scattering correlation spectroscopy and transmission electron microscopy, which demonstrated that the average diameter of the drug carrier system is 98±15 nm, the polydispersity index is 0.18, the zeta potential is −35 mV, and the TP encapsulation efficiency is 48.6% with a controlled release manner. The methylthiazolyldiphenyl-tetrazolium bromide assay and flow cytometry revealed that PPT could decrease toxicity and apoptosis induced by free TP on RAW264.7 cells, respectively. The detection of reactive oxygen species showed that PPT could decrease the cellular reactive oxygen species induced by TP. Compared with the free TP-treated group, PPT improved the survival rate of the mice (P<0.01) and had no side effects or toxic effects on the thymus index (P>0.05) and spleen index (P>0.05). The blood biochemical indexes revealed that PPT did not cause much damage to the kidney (blood urea nitrogen and creatinine), liver (serum alanine aminotransferase and aspartate aminotransferase), or blood cells (P>0.05). Meanwhile, hematoxylin and eosin staining and terminal-deoxynucleotidyl transferase dUTP nick-end labeling staining indicated that PPT reduced the damage of free TP on the liver, kidney, and spleen. Our results demonstrated that PPT reduced free TP toxicity in vitro and in vivo and that it is a promising fundamental drug delivery system for rheumatoid arthritis treatment.