Homotypic cell membrane-camouflaged biomimetic PLGA nanoparticle loading triptolide for the treatment of hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is the fourth leading cause of cancer-associated death worldwide. Beside early detection, early diagnosis, and early surgery, it is urgent to try new strategies for the treatment of HCC. Triptolide (TPL) has been employed to treat HCC. However, its clinical applications were restricted by the narrow therapeutic window, severe toxicity, and poor water-solubility. In this study, we developed cancer cell membrane-camouflaged biomimetic PLGA nanoparticles loading TPL (TPL@mPLGA) with the homologous targeting property for the treatment of HCC. The TPL@mPLGA was successfully prepared with particle size of 195.5 ± 7.5 nm and zeta potential at -21.5 ± 0.2 mV with good stability. The drug loading (DL) of TPL@mPLGA was 2.94%. After Huh-7 cell membrane coating, the natural Huh-7 cell membrane proteins were found to be retained on TPL@mPLGA, thus endowing the TPL@mPLGA with enhanced accumulation at tumor site, and better anti-tumor activity in vitro and in vivo when compared with TPL or TPL@PLGA. The TPL@mPLGA showed enhanced anti-tumor effects and reduced toxicity of TPL, which could be adopted for the treatment of HCC.

Self-Amplified pH/ROS Dual-Responsive Co-Delivery Nano-System with Chemo-Photodynamic Combination Therapy in Hepatic Carcinoma Treatment.

Background: Chemo-photodynamic combination therapy has demonstrated significant potential in the treatment of cancer. Triptolide (TPL), a naturally derived anticancer agent, when combined with the photosensitizer Chlorin e6 (Ce6), has shown to provide enhanced anti-tumor benefits. However, the development of stimuli-responsive nanovehicles for the co-delivery of TPL and Ce6 could further enhance the efficacy of this combination therapy. Methods: In this study, we synthesized a pH/ROS dual-responsive mPEG-TK-PBAE copolymer, which contains a pH-sensitive PBAE moiety and a ROS-sensitive thioketal (TK) linkage. Through a self-assembly process, TPL and Ce6 were successfully co-loaded into mPEG-TK-PBAE nanoparticles, hereafter referred to as TPL/Ce6 NPs. We evaluated the pH- and ROS-sensitive drug release and particle size changes. Furthermore, we investigated both the in vitro suppression of cellular proliferation and induction of apoptosis in HepG2 cells, as well as the in vivo anti-tumor efficacy of TPL/Ce6 NPs in H22 xenograft nude mice. Results: The mPEG-TK-PBAE copolymer was synthesized through a one-pot Michael-addition reaction and successfully co-encapsulated both TPL and Ce6 by self-assembly. Upon exposure to acid pH values and high ROS levels, the payloads in TPL/Ce6 NPs were rapidly released. Notably, the abundant ROS generated by the released Ce6 under laser irradiation further accelerated the degradation of the nanosystem, thereby amplifying the tumor microenvironment-responsive drug release and enhancing anticancer efficacy. Consequently, TPL/Ce6 NPs significantly increased PDT-induced oxidative stress and augmented TPL-induced apoptosis in HepG2 cells, leading to synergistic anticancer effects in vitro. Moreover, administering TPL/Ce6 NPs (containing 0.3 mg/kg of TPL and 4 mg/kg of Ce6) seven times, accompanied by 650 nm laser irradiation, efficiently inhibited tumor growth in H22 tumor-bearing mice, while exhibiting lower systemic toxicity. Conclusion: Overall, we have developed a tumor microenvironment-responsive nanosystem for the co-delivery of TPL and Ce6, demonstrating amplified synergistic effects of chemo-photodynamic therapy (chemo-PDT) for hepatocellular carcinoma (HCC) treatment.

Targeted drug-loaded peptides induce tumor cell apoptosis and immunomodulation to increase antitumor efficacy.

Immunotherapy is an emerging approach for the treatment of solid tumors. Although chemotherapy is generally considered immunosuppressive, specific chemotherapeutic agents can induce tumor immunity. In this study, we developed a targeted, acid-sensitive peptide nanoparticle (DT/Pep1) to deliver doxorubicin (DOX) and triptolide (TPL) to breast cancer cells via the enhanced permeability and retention (EPR) effect and the breast cancer-targeting effect of peptide D8. Compared with administration of the free drugs, treatment with the DT/Pep1 system increased the accumulation of DOX and TPL at the tumor site and achieved deeper penetration into the tumor tissue. In an acidic environment, DT/Pep1 transformed from spherical nanoparticles to aggregates with a high aspect ratio, which successfully extended the retention of the drugs in the tumor cells and bolstered the anticancer effect. In both in vivo and in vitro experiments, DT/Pep1 effectively blocked the cell cycle and induced apoptosis. Importantly, the DT/Pep1 system efficiently suppressed tumor development in mice bearing 4T1 tumors while simultaneously promoting immune system activation. Thus, the results of this study provide a system for breast cancer therapy and offer a novel and promising platform for peptide nanocarrier-based drug delivery.

Triptolide Administration Alters Immune Responses to Mitigate Insulin Resistance in Obese States.

Individuals who are overweight or obese are at increased risk of developing prediabetes and type 2 diabetes, yet the direct molecular mechanisms that connect diabetes to obesity are not clear. Chronic, sustained inflammation is considered a strong risk factor in these interactions, directed in part by the short-lived gene expression programs encoding for cytokines and pro-inflammatory mediators. In this study, we show that triptolide administration in the C57BL/6 diet-induced obese mice at up to 10 µg/kg/day for 10 weeks attenuated the development of insulin resistance and diabetes, but not obesity, in these animals. Significant reductions in adipose tissue inflammation and improved insulin sensitivity were observed in the absence of changes in food intake, body weight, body composition, or energy expenditure. Analysis of the core cluster of biomarkers that drives pro-inflammatory responses in the metabolic tissues suggested TNF-α as a critical point that affected the co-development of inflammation and insulin resistance, but also pointed to the putatively protective roles of increased COX-2 and IL-17A signaling in the mediation of these pathophysiological states. Our results show that reduction of diet-induced inflammation confers partial protection against insulin resistance, but not obesity, and suggest the possibility of achieving overweight phenotypes that are accompanied by minimal insulin resistance if inflammation is controlled.

Macropinocytic dextran facilitates KRAS-targeted delivery while reducing drug-induced tumor immunity depletion in pancreatic cancer.

Background: Pancreatic cancer comprises not only cancer cells but also a collection of cross-talking noncancerous cells within tumor. Therefore, selective delivery of cytotoxic agents towards cancer cells and limiting the collateral damage to tumor suppressive benign cells, such as effector lymphocytes in the tumor microenvironment, is of great value. Methods: Pancreatic cancer cells harbor oncogenic KRAS which induces a constitutively high level of macropinocytosis. Inspired by such uniquity, we sought to explore the targeting potential of dextran, a biomaterial presumed to be endocytosed in the macropinocytosis dependent manner. Cell entry preference, mechanism and subcellular sorting of dextran with different molecular weights were firstly examined. Triptolide (TP), a potent cytotoxin was then set as the model payload for dextran conjugation. KRAS selectivity and the therapeutic effects of dextran-conjugated TP were investigated via both in vitro cellular studies and in vivo tumor model assessment. Results: Dextran, with a specific molecular weight of 70 kDa rather than other weights, was identified as a robust KRAS-responsive intracellular delivery carrier with enhanced entry upon KRAS mutation. The 70 kDa dextran-conjugated TP (DEX-TP) displayed greater efficacy and cellular deposition efficiency towards KRAS mutant cells than KRAS wild-type cells. Treatment with DEX-TP suppressed tumor progression in KRAS mutant pancreatic cancer orthotopic mouse models with reduced toxicity and significantly extended mouse survival time. Furthermore, the conjugate attained a more favorable therapeutic outcome in the tumor immune microenvironment than the free drug, preserving the fraction of T cells and their effector cytokines. Conclusions: In summary, macropinocytic dextran was able to provide drug delivery selectivity towards KRAS mutant cancer cells and reduce tumor immunity depletion caused by the cytotoxic drug in pancreatic cancer.

Triptolide protects against white matter injury induced by chronic cerebral hypoperfusion in mice.

White matter injury is the major pathological alteration of subcortical ischemic vascular dementia (SIVD) caused by chronic cerebral hypoperfusion. It is characterized by progressive demyelination, apoptosis of oligodendrocytes and microglial activation, which leads to impairment of cognitive function. Triptolide exhibits a variety of pharmacological activities including anti-inflammation, immunosuppression and antitumor, etc. In this study, we investigated the effects of triptolide on white matter injury and cognitive impairments in mice with chronic cerebral hypoperfusion induced by the right unilateral common carotid artery occlusion (rUCCAO). We showed that triptolide administration alleviated the demyelination, axonal injury, and oligodendrocyte loss in the mice. Triptolide also improved cognitive function in novel object recognition test and Morris water maze test. In primary oligodendrocytes following oxygen-glucose deprivation (OGD), application of triptolide (0.001-0.1 nM) exerted concentration-dependent protection. We revealed that the protective effect of triptolide resulted from its inhibition of oligodendrocyte apoptosis via increasing the phosphorylation of the Src/Akt/GSK3ß pathway. Moreover, triptolide suppressed microglial activation and proinflammatory cytokines expression after chronic cerebral hypoperfusion in mice and in BV2 microglial cells following OGD, which also contributing to its alleviation of white matter injury. Importantly, mice received triptolide at the dose of 20 µg·kg-1·d-1 did not show hepatotoxicity and nephrotoxicity even after chronic treatment. Thus, our results highlight that triptolide alleviates whiter matter injury induced by chronic cerebral hypoperfusion through direct protection against oligodendrocyte apoptosis and indirect protection by inhibition of microglial inflammation. Triptolide may have novel indication in clinic such as the treatment of chronic cerebral hypoperfusion-induced SIVD.

Targeted therapy of rheumatoid arthritis via macrophage repolarization.

The polarization of macrophages plays a critical role in the physiological and pathological progression of rheumatoid arthritis (RA). Activated M1 macrophages overexpress folate receptors in arthritic joints. Hence, we developed folic acid (FA)-modified liposomes (FA-Lips) to encapsulate triptolide (TP) (FA-Lips/TP) for the targeted therapy of RA. FA-Lips exhibited significantly higher internalization efficiency in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells than liposomes (Lips) in the absence of folate. Next, an adjuvant-induced arthritis (AIA) rat model was established to explore the biodistribution profiles of FA-Lips which showed markedly selective accumulation in inflammatory paws. Moreover, FA-Lips/TP exhibited greatly improved therapeutic efficacy and low toxicity in AIA rats by targeting M1 macrophages and repolarizing macrophages from M1 to M2 subtypes. Overall, a safe FA-modified liposomal delivery system encapsulating TP was shown to achieve inflammation-targeted therapy against RA via macrophage repolarization.

Effect of triptolide and chemotherapy on carcinoembryonic and carbohydrate antigens levels and first-line treatment of recurrent nasopharyngeal carcinoma.

To investigate the first-line treatment of recurrent Nasopharyngeal Carcinoma treprimcab combined with chemotherapy. From January 2019 to January 2020, 48 patients with recurrent nasopharyngeal Carcinoma (RNPC) were treated in our hospital. According to the method of the random number, 24 patients were divided into the combined group and the Control Group. The patients in the combined group were given the Combined Treatment of triptolide and chemotherapy. While the Control Group only received chemotherapy. The therapeutic effects and adverse reactions of the two groups were compared, the levels of Carcinoembryonic Antigen (CEA) and carbohydrate Antigen 19-9 (CA19-9) were measured before and after treatment. The total effective rate of the combined group was 79.17% higher than that of the control group (62.50%). The total effective rate of the two groups was statistically significant (P & Lt; 0.05). The incidence of grade i/ii adverse reaction in the control group was lower than that in the combined group, such as nausea and vomiting, oral mucositis, Leukopenia, liver and kidney function damage, central granulocyte count reduction, anaemia adverse reaction. The incidence of grade iii/iv Adr in the control group was higher than that in the combined group. The incidence of grade i/ii Adr in the thrombocytopenia group was higher than that in the combined group, and the incidence of grade iii/iv Adr in the control group was lower than that in the combined group. The side effects of nausea and vomiting and oral mucositis in the control group and the combined group were statistically significant (P & Lt; 0.05). There was no significant difference between the control group and the combined group in the incidence of Leukopenia, liver and kidney injury, neutrophil, anaemia and Thrombocytopenia (P & GT; 0.05). The level of CD4 + / CD8 + in control group and combined group before treatment was higher than that after treatment (P & Lt; 0.05). The quality of life of the combined group was 91.67% higher than that of the control group (70.83%). The quality of life of the control group was significantly higher than that of the combined group (P & Lt; 0.05). The levels of CEA and CA19-9 in the two groups after treatment were lower than those before treatment, and the levels of CEA and CA19-9 in the combined group were lower than those in the control group (P & Lt; 0.05). The first-line treatment of recurrent nasopharyngeal Carcinoma with triprimmab combined with chemotherapy has a good clinical effect and has a broad clinical research prospect.

Transdermal delivery of triptolide-phospholipid complex to treat rheumatoid arthritis.

The aim of this study was to develop and evaluate a triptolide phospholipid complex (TPCX) for the treatment of rheumatoid arthritis (RA) by transdermal delivery. TPCX was prepared and characterized by differential scanning calorimetry (DSC), Fourier-transform infrared spectroscopy (FTIR) analysis, transmission electron microscope (TEM), and scanning electron microscope (SEM). The solubility of TPCX was determined. Then, a TPCX cream was prepared to evaluate its percutaneous permeability and the antiarthritis effect. The transdermal permeability was determined using the Franz method, and a microdialysis system was used for skin pharmacokinetic study. A rat model of RA was prepared to evaluate the pharmacological effects. TPCX increased the solubility of triptolide in water, and the percutaneous permeability of TPCX cream was greatly enhanced compared with triptolide cream. The skin pharmacokinetic study indicated that TPCX cream has a longer biological half-life (t1/2) and mean residence time (MRT), but it has a shorter Tmax than that of triptolide cream in vivo. The area under the curve (AUC0-t)/AUC0-∞) and the peak concentration (Cmax) of TPCX cream were obviously higher than those of triptolide cream. The TPCX-loaded cream alleviated paw swelling and slowed down the progression of arthritis by inhibiting the inflammatory response by down regulating the TNF-α, IL-1ß, and IL-6 levels, thus exhibiting excellent antiarthritic effects. In summary, the prepared TPCX effectively increases the hydrophilicity of triptolide, which is good for its percutaneous absorption and enhances its effect on RA rats. TPCX can be a good candidate for the transdermal delivery to treat RA.

Membrane protein-chimeric liposome-mediated delivery of triptolide for targeted hepatocellular carcinoma therapy.

Triptolide (TPL) is a diterpenoid triepoxide with broad antitumor efficacy, while lack of mechanism of action, severe systemic toxicity, and poor water solubility of TPL limited its usage. To unveil the mechanism of action and improve the pharmaceutical properties of TPL, here we explored the molecular mechanism of TPL and then fabricated TPL-loaded membrane protein-chimeric liposomes (TPL@MP-LP) and tested its anticancer efficacy against hepatocellular carcinoma (HCC). CCK8 assay, colony formation assay, EdU assay, and flow cytometry were used to examine the activity of TPL. RNA sequence and gain-and-loss of function assays were used to explore the molecular mechanisms. TPL@MP-LP was characterized by size, zeta potential, polydispersity index, and transmission electron microscopy. Cellular uptake and cell viability assay were performed to evaluate the internalization and anticancer efficacy of TPL@MP-LP in vitro. Biodistribution and in vivo antitumor efficacy of TPL@MP-LP were evaluated on orthotopic HCC mice models. TPL robustly inhibited HCC cells by inducing cell proliferation arrest, apoptosis via the mitochondrial pathway, and necroptosis via RIPK1/RIPK3/MLKL signaling. TPL was successfully loaded into MP-LP, with a drug-loading capacity of 5.62 ± 0.80%. MP-LP facilitated TPL internalization and TPL@MP-LP exerted enhanced anticancer efficacy against Huh7 cells. TPL@MP-LP showed targeting ability to the tumor site. More importantly, TPL@MP-LP treatment suppressed tumor growth but showed minimal damage to liver and renal functions. TPL exerted anticancer effects on HCC via inducing cell proliferation arrest, apoptosis, and necroptosis, and the MP-LP might be a promising delivery strategy to improve the antitumor efficacy while mitigating toxicity of TPL for HCC therapy.

Mitochondria-A target for attenuation of astrocyte pathology.

Astrocyte pathology is a feature of neuromyelitis optica spectrum disorder (NMOSD) pathology. Recently mitochondrial dysfunction and metabolic changes were suggested to play a role in NMOSD. To elucidate the role of mitochondrial dysfunction, astrocyte pathology was induced in C57BL/6 J female mice by intracerebral injection of aquaporin-4-immunoglobulin G from an NMOSD patient, together with complement. Etomoxir has been shown to cause mitochondrial dysfunction. Etomoxir was delivered to the central nervous system and resulted in decreased astrocyte pathology. The ameliorating effect was associated with increases in different acylcarnitines and amino acids. This suggests that mitochondria may be a therapeutic target in NMOSD.

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.

Triptolide delivery: Nanotechnology-based carrier systems to enhance efficacy and limit toxicity.

Triptolide (TP) possesses a wide range of biological and pharmacological activities involved in the treatment of various diseases. However, widespread usages of TP raise the urgent issues of the severe toxicity, which hugely limits its further clinical application. The novel functional nanostructured delivery system, which is of great significance in enhancing the efficacy, reducing side effects and improving bioavailability, could improve the enrichment, penetration and controlled release of drugs in the lesion location. Over the past decades, considerable efforts have been dedicated to designing and developing a variety of TP delivery systems with the intention of alleviating the adverse toxicity effects and enhancing the bioavailability. In this review, we briefly summarized and discussed the recent functionalized nano-TP delivery systems for the momentous purpose of guiding further development of novel TP delivery systems and providing perspectives for future clinical applications.

Urinary Excretion of 2/3-Monochloropropanediol (2/3-MCPD) and 2,3-Dihydroxypropylmercapturic Acid (DHPMA) after a Single High dose of Fatty Acid Esters of 2/3-MCPD and Glycidol: A Controlled Exposure Study in Humans.

SCOPE: 2- and 3-monochloropropanediol (2/3-MCPD) and glycidol are absorbed in the intestine after lipase-catalyzed hydrolysis of their fatty acid esters. METHODS AND RESULTS: In an exposure study with 12 non-smoking participants, the complete urinary excretion of the metabolite 2,3-dihydroxypropylmercapturic acid (DHPMA) and of 2/3-MCPD is measured on four consecutive days before and after consumption of 50 g glycidyl ester-rich palm fat or 12 g 2/3-MCPD ester-rich hazelnut oil. After controlled exposure, urinary excretion rates of 2/3-MCPD per hour strongly increase, followed by a decrease with average half-lives of 5.8 h (2-MCPD) and 3.6 h (3-MCPD). After consumption of hazelnut oil, mean excretion rates are 14.3% (2-MCPD) and 3.7% (3-MCPD) of the study doses. The latter rate is significantly higher (4.6%) after consumption of palm fat, indicating partial conversion (about 5%) of glycidol to 3-MCPD under the acidic conditions in the stomach. The average daily "background" exposure is estimated to be 0.12 and 0.32 µg per kg body weight (BW) for 2-MCPD and 3-MCPD, respectively. The relatively high and constant urinary excretion of DHPMA does not reflect the controlled exposure. CONCLUSION: Urinary excretion of 2- and 3-MCPD is suitable as biomarker for the external exposure to the respective fatty acid esters.

Triptolide-nanoliposome-APRPG, a novel sustained-release drug delivery system targeting vascular endothelial cells, enhances the inhibitory effects of triptolide on laser-induced choroidal neovascularization.

PURPOSE: To investigate whether triptolide-nanoliposome-APRPG (TP-nanolip-APRPG), a novel sustained-release nano-drug delivery system that targets vascular endothelial cells, could enhance the inhibition of triptolide (TP) on laser-induced choroidal neovascularization (CNV). METHODS: TP was encapsulated with or without APRPG (Ala-Pro-Arg-Pro-Gly) peptide-modified nanoliposomes. CNV was induced by laser photocoagulation in C57BL/6J mice. One microliter of 10 µg free TP monomer, TP-nanolip containing 10 µg TP, TP-nanolip-APRPG containing 10 µg TP, or an identical volume of PBS was intravitreally injected in mice immediately after laser photocoagulation. Seven days after laser photocoagulation, CNV volumes were calculated in each group. Infiltration of M2 macrophages as well as protein levels of vascular endothelial growth factor (VEGF) and inflammatory factors including ICAM-1 and MCP-1 in the RPE-choroid complex were determined. In vitro assays for cell proliferation, migration, and tube formation were also performed. RESULTS: TP-nanolip-APRPG was successfully synthesized and exhibited good TP delivery and enhanced the cellular uptake of TP in vitro. In vitro studies showed that TP-nanolip-APRPG was a better inhibitor of cell proliferation (31.34 ±â€¯3.89 % vs 41.25 ±â€¯4.67 % vs 53.55 ±â€¯5.76 %), migration (62.60 ±â€¯8.88 vs 104.60 ±â€¯13.32 vs 147.00 ±â€¯13.15), and tube formation (681.26 ±â€¯108.15 vs 926.75 ±â€¯54.01 vs 1189.84 ±â€¯157.14) than TP-nanolip or free TP (all P < 0.05). Intravitreal injections of free TP (77588.10±7719.28 µm3), TP-nanolip (64628.23 ±â€¯5857.96 µm3), and TP-nanolip-APRPG (50880.34 ±â€¯6606.56 µm3) inhibited the development of CNV compared with the PBS control group (120338.07 ±â€¯17428.90 µm3) (P < 0.01, n=6). TP-nanolip-APRPG and TP-nanolip significantly down-regulated the protein levels of VEGF (152.76±19.55 vs 182.24±19.98 vs 208.55±21.93 pg/mg total protein) and inflammatory factors including ICAM-1 (61.69±3.49 vs 72.04±3.49 vs 81.92±4.09 ng/mg total protein) and MCP-1 (40.14±3.50 vs 50.75±4.18 vs 60.27±5.23 pg/mg total protein) compared with the free TP monomer group (all P < 0.05, n=8), which paralleled the decreased infiltration of M2 macrophages in the CNV lesions. Moreover, no influence on retinal morphology and function was observed before or after treatment in each group (P > 0.05, n=6). CONCLUSIONS: TP-nanolip-APRPG, a novel sustained-release drug delivery system targeting endothelial cells of CNV lesions, could enhance TP inhibition of the development of CNV without toxicity in the retina, suggesting therapeutic potential for CNV-related diseases in future clinical practice.

Pharmacological inhibition of carnitine palmitoyl transferase 1 inhibits and reverses experimental autoimmune encephalitis in rodents.

Multiple sclerosis (MS) is a neurodegenerative disease characterized by demyelination and inflammation. Dysregulated lipid metabolism and mitochondrial dysfunction are hypothesized to play a key role in MS. Carnitine Palmitoyl Transferase 1 (CPT1) is a rate-limiting enzyme for beta-oxidation of fatty acids in mitochondria. The therapeutic effect of pharmacological CPT1 inhibition with etomoxir was investigated in rodent models of myelin oligodendrocyte glycoprotein- and myelin basic protein-induced experimental autoimmune encephalitis (EAE). Mice receiving etomoxir showed lower clinical score compared to placebo, however this was not significant. Rats receiving etomoxir revealed significantly lower clinical score and lower body weight compared to placebo group. When comparing etomoxir with interferon-ß (IFN-ß), IFN-ß had no significant therapeutic effects, whereas etomoxir treatment starting at day 1 and 5 significantly improved the clinical scores compared to the IFN-ß and the placebo group. Immunohistochemistry and image assessments of brain sections from rats with EAE showed higher myelination intensity and decreased expression of CPT1A in etomoxir-treated rats compared to placebo group. Moreover, etomoxir mediated increased interleukin-4 production and decreased interleukin-17α production in activated T cells. In conclusion, CPT1 is a key protein in the pathogenesis of EAE and MS and a crucial therapeutic target for the treatment.

Triptolide alleviates radiation-induced pulmonary fibrosis via inhibiting IKKß stimulated LOX production.

Lysyl oxidase (LOX) is involved in fibrosis by catalyzing collagen cross-linking. Previous work observed that Triptolide (TPL) alleviated radiation-induced pulmonary fibrosis (RIPF), but it is unknown whether the anti-RIPF effect of TPL is related to LOX. In a mouse model of RIPF, we found that LOX persistently increased in RIPF which was significantly lowered by TPL. Excessive LOX aggravated fibrotic lesions in RIPF, while LOX inhibition mitigated RIPF. Irradiation enhanced the transcription and synthesis of LOX by lung fibroblasts through IKKß/NFκB activation, and siRNA knockdown IKKß largely abolished LOX production. By interfering radiation induced IKKß activation, TPL prevented NFκB nuclear translocation and DNA binding, and potently decreased LOX synthesis. Our results demonstrate that the anti-RIPF effect of TPL is associated with reduction of LOX production which mediated by inhibition of IKKß/NFκB pathway.

Triptolide inhibits epithelial­mesenchymal transition and induces apoptosis in gefitinib­resistant lung cancer cells.

The epidermal growth factor receptor­tyrosine kinase inhibitor (EGFR­TKI), gefitinib, is used widely to treat non­small cell lung cancer (NSCLC) with EGFR­activating mutations. Unfortunately, the acquired drug resistance promoted by epithelial­mesenchymal transition (EMT) markedly limits the clinical effects and remains a major barrier to a cure. Our previous isobaric tags for relative and absolute quantitation­based proteomics analysis revealed that the E­cadherin protein level was markedly upregulated by triptolide (TP). The present study aimed to determine whether TP reverses the gefitinib resistance of human lung cancer cells by regulating EMT. It was revealed that TP combined with gefitinib synergistically inhibited the migration and invasion of lung adenocarcinoma cell line A549; the combination treatment had a significantly better outcome than that of TP and gefitinib alone. Moreover, TP effectively increased the sensitivity of drug resistant A549 cells to gefitinib by upregulating E­cadherin protein expression and downregulating the MMP9, SNAIL, and vimentin expression levels. The dysregulated E­cadherin expression of gefitinib­sensitive cells induced gefitinib resistance, which could be overcome by TP. Finally, TP combined with gefitinib significantly inhibited the growth of xenograft tumors induced using gefitinib­resistant A549 cells, which was associated with EMT reversal and E­cadherin signaling activation in vivo. The present results indicated that the combination of TP and TKIs may be a promising therapeutic strategy to treat patients with NSCLCs harboring EGFR mutations.

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.

Triptolide interrupts rRNA synthesis and induces the RPL23­MDM2­p53 pathway to repress lung cancer cells.

Lung cancer has one of the highest mortalities of any cancer worldwide. Triptolide (TP) is a promising tumor suppressor extracted from the Chinese herb Tripterygium wilfordii. Our previous proteomics analysis revealed that TP significantly interfered with the ribosome biogenesis pathway; however, the underlying molecular mechanism remains poorly understood. The aim of the present study was to determine the molecular mechanism of TP's anticancer effect by investigating the association between ribosomal stress and p53 activation. It was found that TP induces nucleolar disintegration together with RNA polymerase I (Pol I) and upstream binding factor (UBF) translocation. TP interrupted ribosomal (r)RNA synthesis through inhibition of RNA Pol I and UBF transcriptional activation. TP treatment increased the binding of ribosomal protein L23 (RPL23) to mouse double minute 2 protein (MDM2), resulting in p53 being released from MDM2 and stabilized. Activation of p53 induced apoptosis and cell cycle arrest by enhancing the activation of p53 upregulated modulator of apoptosis, caspase 9 and caspase 3, and suppressing BCL2. In vivo experiments showed that TP significantly reduced xenograft tumor size and increased mouse body weight. Immunohistochemical assays confirmed that TP significantly increased the p53 level and induced nucleolus disintegration, during which nucleolin distribution moved from the nucleolus to the nucleoplasm, and RPL23 clustered at the edge of the cell membrane. Therefore, it was proposed that TP induces ribosomal stress, which leads to nucleolus disintegration, and inhibition of rRNA transcription and synthesis, resulting in increased binding of RPL23 with MDM2. Consequently, p53 is activated, which induces apoptosis and cell cycle arrest.