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.

Novel phenanthrene/bibenzyl trimers from the tubers of Bletilla striata attenuate neuroinflammation via inhibition of NF-κB signaling pathway.

Five novel (9,10-dihydro) phenanthrene and bibenzyl trimers, as well as two previously identified biphenanthrenes and bibenzyls, were isolated from the tubers of Bletilla striata. Their structures were elucidated through comprehensive analyses of NMR and HRESIMS spectroscopic data. The absolute configurations of these compounds were determined by calculating rotational energy barriers and comparison of experimental and calculated ECD curves. Compounds 5b and 6 exhibited inhibitory effects on LPS-induced NO production in BV-2 cells, with IC50 values of 12.59 ± 0.40 and 15.59 ± 0.83 µmol·L-1, respectively. A mechanistic study suggested that these compounds may attenuate neuroinflammation by reducing the activation of the AKT/IκB/NF-κB signaling pathway. Additionally, compounds 3a, 6, and 7 demonstrated significant PTP1B inhibitory activities, with IC50 values of 1.52 ± 0.34, 1.39 ± 0.11, and 1.78 ± 0.01 µmol·L-1, respectively. Further investigation revealed that compound 3a might inhibit LPS-induced PTP1B overexpression and NF-κB activation, thereby mitigating the neuroinflammatory response in BV-2 cells.

From Antagonism to Enhancement: Triton X-100 Surfactant Affects Phenanthrene Interfacial Biodegradation by Mycobacteria through a Shift in Uptake Mechanisms.

Polycyclic aromatic hydrocarbons (PAHs), as persistent environmental pollutants, often reside in nonaqueous-phase liquids (NAPLs). Mycobacterium sp. WY10, boasting highly hydrophobic surfaces, can adsorb to the oil-water interface, stabilizing the Pickering emulsion and directly accessing PAHs for biodegradation. We investigated the impact of Triton X-100 (TX100) on this interfacial uptake of phenanthrene (PHE) by Mycobacteria, using n-tetradecane (TET) and bis-(2-ethylhexyl) phthalate (DEHP) as NAPLs. Interfacial tension, phase behavior, and emulsion stability studies, alongside confocal laser scanning microscopy and electron microscope observations, unveiled the intricate interplay. In surfactant-free systems, Mycobacteria formed stable W/O Pickering emulsions, directly degrading PHE within the NAPLs because of their intimate contact. Introducing low-dose TX100 disrupted this relationship. Preferentially binding to the cells, the surfactant drastically increased the cell hydrophobicity, triggering desorption from the interface and phase separation. Consequently, PAH degradation plummeted due to hindered NAPL access. Higher TX100 concentrations flipped the script, creating surfactant-stabilized O/W emulsions devoid of interfacial cells. Surprisingly, PAH degradation remained efficient. This paradox can be attributed to NAPL emulsification, driven by the surfactant, which enhanced mass transfer and brought the substrate closer to the cells, despite their absence at the interface. This study sheds light on the complex effect of surfactants on Mycobacteria and PAH uptake, revealing an antagonistic effect at low concentrations that ultimately leads to enhanced degradation through emulsification at higher doses. These findings offer valuable insights into optimizing bioremediation strategies in PAH-contaminated environments.

Salvia miltiorrhiza inhibited lung cancer through aerobic glycolysis suppression.

Lung cancer causes the most cancer deaths and needs new treatment strategies urgently. Salvia miltiorrhiza is a classical Chinese herb and a strong candidate for tumor treatment. The study found that the aqueous extract of Salvia miltiorrhiza (DSAE), ethanol extract of Salvia miltiorrhiza (DSEE), and its active components danshensu (DSS) and dihydrotanshinone I (DHI), exhibited antineoplastic effects in vivo and in vitro. Meanwhile, DSAE, DSEE, DSS, and DHI reduced glycolysis metabolites (ATP, lactate, and pyruvate contents) production, decreased aerobic glycolysis enzymes, and inhibited Seahorse indexes (OCR and ECAR) in Lewis lung cancer cells (LLC). Data suggests that aerobic glycolysis could be inhibited by Salvia miltiorrhiza and its components. The administration of DSS and DHI further reduced the level of HKII in lung cancer cell lines that had been inhibited with HK-II antagonists (2-deoxyglucose, 2-DG; 3-bromo-pyruvate, 3-BP) or knocked down with siRNA, thereby exerting an anti-lung cancer effect. Although DSS and DHI decreased the level of HKII in HKII-Knock-In lung cancer cell line, their anti-lung cancer efficacy remained limited due to the persistent overexpression of HKII in these cells. Reiterating the main points, we have discovered that the anti-lung cancer effects of Salvia miltiorrhiza may be attributed to its ability to regulate HKII expression levels, thereby inhibiting aerobic glycolysis. This study not only provides a new research paradigm for the treatment of cancer by Salvia miltiorrhiza, but also highlights the important link between glucose metabolism and the effect of Salvia Miltiorrhiza.

Triptolide, a Cancer Cell Proliferation Inhibitor, Causes Zebrafish Muscle Defects by Regulating Notch and STAT3 Signaling Pathways.

Triptolide is a natural compound in herbal remedies with anti-inflammatory and anti-proliferative properties. We studied its effects on critical signaling processes within the cell, including Notch1 and STAT3 signaling. Our research showed that triptolide reduces cancer cell proliferation by decreasing the expression of downstream targets of these signals. The levels of each signal-related protein and mRNA were analyzed using Western blot and qPCR methods. Interestingly, inhibiting one signal with a single inhibitor alone did not significantly reduce cancer cell proliferation. Instead, MTT assays showed that the simultaneous inhibition of Notch1 and STAT3 signaling reduced cell proliferation. The effect of triptolide was similar to a combination treatment with inhibitors for both signals. When we conducted a study on the impact of triptolide on zebrafish larvae, we found that it inhibited muscle development and interfered with muscle cell proliferation, as evidenced by differences in the staining of myosin heavy chain and F-actin proteins in confocal fluorescence microscopy. Additionally, we noticed that inhibiting a single type of signaling did not lead to any significant muscle defects. This implies that triptolide obstructs multiple signals simultaneously, including Notch1 and STAT3, during muscle development. Chemotherapy is commonly used to treat cancer, but it may cause muscle loss due to drug-related adverse reactions or other complex mechanisms. Our study suggests that anticancer agents like triptolide, inhibiting essential signaling pathways including Notch1 and STAT3 signaling, may cause muscle atrophy through anti-proliferative activity.

Bergenin attenuates triptolide-caused premature ovarian failure in mice based on the antioxidant activity.

Tripterygium wilfordii (TW) preparations have been utilized in China for treating rheumatoid arthritis and autoimmune diseases. However, their clinical use is limited due to reproductive toxicity, notably premature ovarian failure (POF). Our study aimed to investigate the effect and mechanism of bergenin in attenuating POF induced by triptolide in mice. POF was induced in female ICR mice via oral triptolide administration (50 µg/kg) for 60 days. Mice received bergenin (25, 50, 100 mg/kg, i.g.) or estradiol valerate (EV) (0.1 mg/kg, i.g.) daily, 1 h before triptolide treatment. In vitro, ovarian granulosa cells (OGCs) were exposed to triptolide (100 nM) and bergenin (1, 3, 10 µM). Antioxidant enzyme activity, protein expression, apoptosis rate, and reactive oxygen species (ROS) levels were assessed. The results showed that triptolide-treated mice exhibited evident atrophy, along with an increase in atretic follicles. Bergenin (50, 100 mg/kg) and EV (0.1 mg/kg), orally administered, exerted significant anti-POF effect. Bergenin and EV also decreased apoptosis in mouse ovaries. In vitro, bergenin (1, 3, 10 µM) attenuated triptolide-induced OGCs apoptosis by reducing levels of apoptosis-related proteins. Additionally, bergenin reduced oxidative stress through downregulation of antioxidant enzymes activity and overall ROS levels. Moreover, the combined use with Sh-Nrf2 resulted in a reduced protection of bergenin against triptolide-induced apoptosis of OGCs. Together, bergenin counteracts triptolide-caused POF in mice by inhibiting Nrf2-mediated oxidative stress and preventing OGC apoptosis. Combining bergenin with TW preparations may effectively reduce the risk of POF.

Suppression of retinal neovascularization by intravitreal injection of cryptotanshinone.

Neovascular eye diseases, including proliferative diabetic retinopathy and retinopathy of prematurity, is a major cause of blindness. Laser ablation and intravitreal anti-VEGF injection have shown their limitations in treatment of retinal neovascularization. Identification of a new therapeutic strategies is in urgent need. Our study aims to assess the effects of Cryptotanshinone (CPT), a natural compound derived from Salvia miltiorrhiza Bunge, in retina neovascularization and explore its potential mechanism. Our study demonstrated that CPT did not cause retina tissue toxicity at the tested concentrations. Intravitreal injections of CPT reduced pathological angiogenesis and promoted physical angiogenesis in oxygen-induced retinopathy (OIR) model. CPT improve visual function in OIR mice and reduced cell apoptosis. Moreover, we also revealed that CPT diminishes the expression of inflammatory cytokines in the OIR retina. In vitro, the administration of CPT effectively inhibited endothelial cells proliferation, migration, sprouting, and tube formation induced by the stimulation of human retinal vascular endothelial cells (HRVECs) with VEGF165. Mechanistically, CPT blocking the phosphorylation of VEGFR2 and downstream targeting pathway. After all, the findings demonstrated that CPT exhibits potent anti-angiogenic and anti-inflammatory effects in OIR mice, and it has therapeutic potential for the treatment of neovascular retinal diseases.

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 alleviates cerebral ischemia/reperfusion injury via regulating the Fractalkine/CX3CR1 signaling pathway.

PURPOSE: To evaluate the potential efficacy of Triptolide (TP) on cerebral ischemia/reperfusion injury (CIRI) and to uncover the underlying mechanism through which TP regulates CIRI. METHODS: We constructed a middle cerebral artery occlusion/reperfusion (MCAO/R) mouse model to simulate CIRI, and established a lipopolysaccharide (LPS)-stimulated BV-2 cell model to mimic the inflammatory state during CIRI. The neurological deficits score (NS) of mice were measured for assessment of neurologic functions. Both the severity of cerebral infarction and the apoptosis level in mouse brain tissues or cells were respectively evaluated using corresponding techniques. The expression levels of Ionized calcium binding adapter molecule 1 (IBA-1), Inductible Nitric Oxide Synthase (iNOS), Arginase 1 (Arg-1), Tumor necrosis factor-α (TNF-α), Interleukin 1ß (IL-1ß), Cysteine histoproteinase S (CTSS), Fractalkine, chemokine C-X3-C motif receptor 1 (CX3CR1), BCL-2-associated X protein (BAX), and antiapoptotic proteins (Bcl-2) were detected using immunofluorescence, qRT-PCR as well as Western blot, respectively. RESULTS: Relative to the Sham group, treatment with TP attenuated the increased NS, infarct area and apoptosis levels observed in MCAO/R mice. Upregulated expression levels of IBA-1, iNOS, Arg-1, TNF-α and IL-1ß were found in MCAO/R mice, while TP suppressed iNOS, TNF-α and IL-1ß expression, and enhanced Arg-1 expression in both MCAO/R mice and LPS-stimulated BV-2 cells. Besides, TP inhibited the CTSS/Fractalkine/CX3CR1 pathway activation in both MCAO/R mice and LPS-induced BV-2 cells, while overexpression of CTSS reversed such effect. Co-culturing HT-22 cells with TP+LPS-treated BV-2 cells led to enhanced cell viability and decreased apoptosis levels. However, overexpression of CTSS further aggravated HT-22 cell injury. CONCLUSION: TP inhibits not only microglia polarization towards the M1 phenotype by suppressing the CTSS/Fractalkine/CX3CR1 pathway activation, but also HT-22 apoptosis by crosstalk with BV-2 cells, thereby ameliorating CIRI. These findings reveal a novel mechanism of TP in improving CIRI, and offer potential implications for addressing the preventive and therapeutic strategies of CIRI.

Label-free cell phenotypic profiling of histamine H4R receptor and discovery of non-competitive H4R antagonist from natural products.

Histamine 4 receptor (H4R), the most recently identified subtype of histamine receptor, primarily induces inflammatory reactions upon activation. Several H4R antagonists have been developed for the treatment of inflammatory bowel disease (IBD) and atopic dermatitis (AD), but their use has been limited by adverse side effects, such as a short half-life and toxicity. Natural products, as an important source of anti-inflammatory agents, offer minimal side effects and reduced toxicity. This work aimed to identify novel H4R antagonists from natural products. An H4R target-pathway model deconvoluted downstream Gi and MAPK signaling pathways was established utilizing cellular label-free integrative pharmacology (CLIP), on which 148 natural products were screened. Cryptotanshinone was identified as selective H4R antagonist, with an IC50 value of 11.68 ± 1.30 µM, which was verified with Fluorescence Imaging Plate Reader (FLIPR) and Cellular Thermal Shift (CTS) assays. The kinetic binding profile revealed the noncompetitive antagonistic property of cryptotanshinone. Two allosteric binding sites of H4R were predicted using SiteMap, Fpocket and CavityPlus. Subsequent molecular docking and dynamics simulation indicated that cryptotanshinone interacts with H4R at a pocket formed by the outward interfaces between TM3/4/5, potentially representing a new allosteric binding site for H4R. Overall, this study introduced cryptotanshinone as a novel H4R antagonist, offering promise as a new hit for drug design of H4R antagonist. Additionally, this study provided a novel screening model for the discovery of H4R antagonists.

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.

Dihydrotanshinone I inhibits gallbladder cancer growth by targeting the Keap1-Nrf2 signaling pathway and Nrf2 phosphorylation.

BACKGROUND: Gallbladder cancer (GBC) poses a significant risk to human health. Its development is influenced by numerous factors, particularly the homeostasis of reactive oxygen species (ROS) within cells. This homeostasis is crucial for tumor cell survival, and abnormal regulation of ROS is associated with the occurrence and progression of many cancers. Dihydrotanshinone I (DHT I), a biologically effective ingredient isolated from Salvia miltiorrhiza, has exhibited cytotoxic properties against various tumor cells by inducing apoptosis. However, the precise molecular mechanisms by which dht I exerts its cytotoxic effects remain unclear. PURPOSE: To explore the anti-tumor impact of dht I on GBC and elucidate the potential molecular mechanisms. METHODS: The proliferation of GBC cells, NOZ and SGC-996, was assessed using various assays, including CCK-8 assay, colony formation assay and EdU staining. We also examined cell apoptosis, cell cycle progression, ROS levels, and alterations in mitochondrial membrane potential to delve into the intricate molecular mechanism. Quantitative PCR (qPCR), immunofluorescence staining, and Western blotting were performed to evaluate target gene expression at both the mRNA and protein levels. The correlation between nuclear factor erythroid 2-related factor 2 (Nrf2) and kelch-like ECH-associated protein 1 (Keap1) were examined using co-immunoprecipitation. Finally, the in vivo effect of dht I was investigated using a xenograft model of gallbladder cancer in mice. RESULTS: Our research findings indicated that dht I exerted cytotoxic effects on GBC cells, including inhibiting proliferation, disrupting mitochondrial membrane potential, inducing oxidative stress and apoptosis. Our in vivo studies substantiated the inhibition of dht I on tumor growth in xenograft nude mice. Mechanistically, dht I primarily targeted Nrf2 by promoting Keap1 mediated Nrf2 degradation and inhibiting protein kinase C (PKC) induced Nrf2 phosphorylation. This leads to the suppression of Nrf2 nuclear translocation and reduction of its target gene expression. Moreover, Nrf2 overexpression effectively counteracted the anti-tumor effects of dht I, while Nrf2 knockdown significantly enhanced the inhibitory effect of dht I on GBC. Meanwhile, PKC inhibitors and nuclear import inhibitors increased the sensitivity of GBC cells to dht I treatment. Conversely, Nrf2 activators, proteasome inhibitors, antioxidants and PKC activators all antagonized dht I induced apoptosis and ROS generation in NOZ and SGC-996 cells. CONCLUSION: Our findings indicated that dht I inhibited the growth of GBC cells by regulating the Keap1-Nrf2 signaling pathway and Nrf2 phosphorylation. These insights provide a strong rationale for further investigation of dht I as a potential therapeutic agent for GBC treatment.

The multifaceted mechanisms of Dihydrotanshinone I in the treatment of tumors.

The morbidity and mortality of malignant tumors are progressively rising on an annual basis. Traditional Chinese Medicine (TCM) holds promise as a possible therapeutic agent for the avoidance or therapy of malignant tumors. Salvia miltiorrhiza Bunge (Danshen), a traditional Asian functional food, has therapeutic characteristics in application for the treatment of malignant tumors. Dihydrotanshinone I (DHTS) is the principal lipophilic phenanthraquinone compound found in Salvia miltiorrhiza Bunge, whose anti-tumor effect has attracted widespread attention. The anti-tumor effects include inhibiting cancer cell proliferation, triggering apoptosis of tumor cells, inducing ferroptosis in tumor cells, inhibiting tumor cell invasion and metastasis, and improving drug resistance of tumor cells. In this paper, we summarized and analyzed the mechanisms and targets of anti-tumor effect of DHTS, providing new ideas and establishing a solid theoretical basis for the future advancement and clinical treatment of DHTS.

Minnelide suppresses GVHD and enhances survival while maintaining GVT responses.

Allogeneic hematopoietic stem cell transplantation (aHSCT) can cure patients with otherwise fatal leukemias and lymphomas. However, the benefits of aHSCT are limited by graft-versus-host disease (GVHD). Minnelide, a water-soluble analog of triptolide, has demonstrated potent antiinflammatory and antitumor activity in several preclinical models and has proven both safe and efficacious in clinical trials for advanced gastrointestinal malignancies. Here, we tested the effectiveness of Minnelide in preventing acute GVHD as compared with posttransplant cyclophosphamide (PTCy). Strikingly, we found Minnelide improved survival, weight loss, and clinical scores in an MHC-mismatched model of aHSCT. These benefits were also apparent in minor MHC-matched aHSCT and xenogeneic HSCT models. Minnelide was comparable to PTCy in terms of survival, GVHD clinical score, and colonic length. Notably, in addition to decreased donor T cell infiltration early after aHSCT, several regulatory cell populations, including Tregs, ILC2s, and myeloid-derived stem cells in the colon were increased, which together may account for Minnelide's GVHD suppression after aHSCT. Importantly, Minnelide's GVHD prevention was accompanied by preservation of graft-versus-tumor activity. As Minnelide possesses anti-acute myeloid leukemia (anti-AML) activity and is being applied in clinical trials, together with the present findings, we conclude that this compound might provide a new approach for patients with AML undergoing aHSCT.

Inhibition of PARP1 improves cardiac function after myocardial infarction via up-regulated NLRC5.

The incidence and mortality rate of myocardial infarction are increasing per year in China. The polarization of macrophages towards the classically activated macrophages (M1) phenotype is of utmost importance in the progression of inflammatory stress subsequent to myocardial infarction. Poly (ADP-ribose) polymerase 1(PARP1) is the ubiquitous and best characterized member of the PARP family, which has been reported to support macrophage polarization towards the pro-inflammatory phenotype. Yet, the role of PARP1 in myocardial ischemic injury remains to be elucidated. Here, we demonstrated that a myocardial infarction mouse model induced cardiac damage characterized by cardiac dysfunction and increased PARP1 expression in cardiac macrophages. Inhibition of PARP1 by the PJ34 inhibitors could effectively alleviate M1 macrophage polarization, reduce infarction size, decrease inflammation and rescue the cardiac function post-MI in mice. Mechanistically, the suppression of PARP1 increase NLRC5 gene expression, and thus inhibits the NF-κB pathway, thereby decreasing the production of inflammatory cytokines such as IL-1ß and TNF-α. Inhibition of NLRC5 promote infection by effectively abolishing the influence of this mechanism discussed above. Interestingly, inhibition of NLRC5 promotes cardiac macrophage polarization toward an M1 phenotype but without having major effects on M2 macrophages. Our results demonstrate that inhibition of PARP1 increased NLRC5 gene expression, thereby suppressing M1 polarization, improving cardiac function, decreasing infarct area and attenuating inflammatory injury. The aforementioned findings provide new insights into the proinflammatory mechanisms that drive macrophage polarization following myocardial infarction, thereby introducing novel potential targets for future therapeutic interventions in individuals affected by myocardial infarction.

Sodium tanshinone IIA sulfonate suppresses microglia polarization and neuroinflammation possibly via regulating miR-125b-5p/STAT3 axis to ameliorate neuropathic pain.

The spinal cord microglia play a pivotal role in neuroinflammation and neuropathic pain (NP). Sodium tanshinone IIA sulfonate (STS), a derivative of tanshinone IIA, has anti-inflammatory and anti-hyperalgesic effects. However, its underlying mechanism in NP remains unclear. This study aimed to investigate the effect of STS and elucidate possible mechanisms in a rat model of spared nerve injury. In vivo experiments, STS and AG490 were administered intraperitoneally once daily for 14 consecutive days after surgery. The results showed that the expression of miR-125b-5p in the spinal dorsal horn was substantially reduced, whereas signal transducer and activator of transcription 3 (STAT3) signaling was increased. After treatment with STS, the mechanical thresholds, expression of miR-125b-5p, and microglial M2 marker such as Arg-1 in the spinal cord horn increased significantly, whereas multiple pro-inflammatory cytokines and apoptosis were significantly reduced. Moreover, STAT3 pathway-related proteins and expression of the microglial M1 marker, CD68, were appreciably inhibited. In vitro, lipopolysaccharide (LPS) was used to induce an inflammatory response in BV-2 microglial cells. STS pretreatment inhibited LPS-stimulated pro-inflammatory cytokine secretion, reduced STAT3 pathway related-proteins and apoptosis, increased miR-125b-5p and proopiomelanocortin expression, and enhanced microglia transformation from M1 to M2 phenotype in BV-2 cells. These effects were reversed after the inhibition of miR-125b-5p expression in BV-2 cells. A dual-luciferase reporter assay confirmed that STAT3 binds to miR-125b-5p. In summary, these results suggest that STS exerts anti-hyperalgesic and anti-neuroinflammatory effects in rats with NP possibly via the miR-125b-5p/STAT3 axis.

Engineered Exosomes Loaded with Triptolide: An Innovative Approach to Enhance Therapeutic Efficacy in Rheumatoid Arthritis.

OBJECTIVES: Exosomes are small, membrane-bound vesicles secreted by cells into the extracellular environment. They play a crucial role in various biological processes, including immune response, cell-to-cell signaling, and tumor progression. Exosomes have attracted attention as potential targets for therapeutic intervention, drug delivery, and biomarker detection. In this study, we aimed to isolate exosomes from human RA fibroblasts (hRAF-Exo) and load them with triptolide (TP) to generate engineered exosomes (hRAF-Exo@TP). METHODS: Transmission electron microscopy, particle size analysis, and western blotting for protein detection were employed to characterize hRAF-Exo. Furthermore, a murine model of collagen-induced arthritis (CIA) was employed to observe the distinct affinity of hRAF-Exo@TP towards the afflicted area. RESULTS: Cellular experiments demonstrated the inhibitory effect of hRAF-Exo@TP on the proliferative activity of human RA fibroblasts. Additionally, it exhibited remarkable selectivity for lesion sites in a CIA mouse model. CONCLUSION: Exosomes loaded with TP may enhance the therapeutic effects on RA in mice. Our study provides a promising avenue for the treatment of RA in the future.

Engineering a pH-responsive polymeric micelle co-loaded with paclitaxel and triptolide for breast cancer therapy.

Breast cancer has overtaken lung cancer as the number one cancer worldwide. Paclitaxel (PTX) is a widely used first-line anti-cancer drug, but it is not very effective in clinical breast cancer therapy. It has been reported that triptolide (TPL) can enhance the anticancer effect of paclitaxel, and better synergistic therapeutic effects are seen with concomitant administration of PTX and TPL. In this study, we developed pH-responsive polymeric micelles for co-delivery of PTX and TPL, which disassembling in acidic tumour microenvironments to target drug release and effectively kill breast cancer cells. Firstly, we synthesized amphiphilic copolymer mPEG2000-PBAE through Michael addition reaction, confirmed by various characterizations. Polymer micelles loaded with TPL and PTX (TPL/PTX-PMs) were prepared by the thin film dispersion method. The average particle size of TPL/PTX-PMs was 97.29 ± 1.63 nm, with PDI of 0.237 ± 0.003 and Zeta potential of 9.57 ± 0.80 mV, LC% was 6.19 ± 0.21%, EE% was 88.67 ± 3.06%. Carrier material biocompatibility and loaded micelle cytotoxicity were assessed using the CCK-8 method, demonstrating excellent biocompatibility. Under the same drug concentration, TPL/PTX-PMs were the most toxic to tumour cells and had the strongest proliferation inhibitory effect. Cellular uptake assays revealed that TPL/PTX-PMs significantly increased intracellular drug concentration and enhanced antitumor activity. Overall, pH-responsive micellar co-delivery of TPL and PTX is a promising approach for breast cancer therapy.

Triptolide induces apoptosis and cytoprotective autophagy by ROS accumulation via directly targeting peroxiredoxin 2 in gastric cancer cells.

Triptolide, a natural bioactive compound derived from herbal medicine Tripterygium wilfordii, has multiple biological activities including anti-cancer effect, which is being tested in clinical trials for treating cancers. However, the exact mechanism by which Triptolide exerts its cytotoxic effects, particularly its specific protein targets, remains unclear. Here, we show that Triptolide effectively induces cytotoxicity in gastric cancer cells by increasing reactive oxygen species (ROS) levels. Further investigations reveal that ROS accumulation contributes to the induction of Endoplasmic Reticulum (ER) stress, and subsequently autophagy induction in response to Triptolide. Meanwhile, this autophagy is cytoprotective. Interestingly, through activity-based protein profiling (ABPP) approach, we identify peroxiredoxins-2 (PRDX2), a component of the key enzyme systems that act in the defense against oxidative stress and protect cells against hydroperoxides, as direct binding target of Triptolide. By covalently binding to PRDX2 to inhibit its antioxidant activity, Triptolide increases ROS levels. Moreover, overexpression of PRDX2 inhibits and knockdown of the expression of PRDX2 increases Triptolide-induced apoptosis. Collectively, these results indicate PRDX2 as a direct target of Triptolides for inducing apoptosis. Our results not only provide novel insight into the underlying mechanisms of Triptolide-induced cytotoxic effects, but also indicate PRDX2 as a promising potential therapeutic target for developing anti-gastric cancer agents.

CHIR-98014, a GSK 3ß Inhibitor, Protects Against Triptolide/Lipopolysaccharide-Induced Hepatotoxicity by Mitochondria-Dependent Apoptosis Inhibition.

Triptolide (TP) is a remarkable anti-inflammatory and immunosuppressive component separated from Tripterygium wilfordii Hook. F. However, its hepatotoxicity limits its application in the clinical. Our group has proposed a new perspective on TP-induced hepatotoxicity, in which TP enhances liver hypersensitivity upon lipopolysaccharide (LPS) stimulation. Because the cause of the disease is unknown, there is currently no uniform treatment available. In this study, we attempted to determine whether the GSK-3ß-JNK pathway affects liver damage and its regulatory mechanism in response to TP/LPS costimulation. In addition, we investigated the effect of CsA or the GSK 3ß inhibitor CHIR-98014 on TP/LPS-induced hepatotoxicity. The results showed that the TP/LPS cotreatment mice exhibited obvious hepatotoxicity, as indicated by a remarkable increase in the serum ALT and AST levels, glycogen depletion, GSK 3ß-JNK upregulation, and increased apoptosis. Instead of the specific knockdown of JNK1, the specific knockdown of JNK2 had a protective effect. Additionally, 40 mg/kg of CsA and 30 mg/kg of CHIR-98014 might provide protection. In summary, CHIR-98014 could protect against TP/LPS- or TP/TNF-α-induced activation of the GSK 3ß-JNK pathway and mitochondria-dependent apoptosis, improving the indirect hepatotoxicity induced by TP.