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Stroke is the second leading cause of death worldwide,and oxidative stress plays a crucial role.Celastrol exhibits strong antioxidant properties in several diseases;however,whether it can affect oxidation in cerebral ischemic-reperfusion injury(CIRI)remains unclear.This study aimed to determine whether celastrol could reduce oxidative damage during CIRI and to elucidate the underlying mechanisms.Here,we found that celastrol attenuated oxidative injury in CIRI by upregulating nuclear factor E2-related factor 2(Nrf2).Using alkynyl-tagged celastrol and liquid chromatography-tandem mass spectrometry,we showed that celastrol directly bound to neuronally expressed developmentally downregulated 4(Nedd4)and then released Nrf2 from Nedd4 in astrocytes.Nedd4 promoted the degradation of Nrf2 through K48-linked ubiquitination and thus contributed to astrocytic reactive oxygen species production in CIRI,which was significantly blocked by celastrol.Furthermore,by inhibiting oxidative stress and astrocyte activation,celastrol effectively rescued neurons from axon damage and apoptosis.Our study uncovered Nedd4 as a direct target of celastrol,and that celastrol exerts an antioxidative effect on as-trocytes by inhibiting the interaction between Nedd4 and Nrf2 and reducing Nrf2 degradation in CIRI.
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Celastrol, extracted from Tripterygium wilfordii, is a natural pentacyclic triterpene compound, which has an anti-pulmonary fibrosis effect. However, its effect, binding targets and regulatory mechanism in pulmonary fibroblasts remain unclear. In this study, we found that celastrol could prevent fibroblast-myofibroblast transformation (FMT) by significantly inhibiting transforming growth factor β1 (TGFβ1)-induced α-smooth muscle actin and type I collagen expression. Previous studies suggested that heat shock protein 60 (HSP60) may be the target of celastrol. This study confirmed the direct interaction between celastrol and HSP60 through cellular thermal shift assay and surface plasmon resonance experiment, and demonstrated that the KD value of celastrol binding to HSP60 was 8.59 μmol·L-1. Further studies showed that knockdown of HSP60 promoted TGFβ1-induced FMT, especially in the medium and low dose TGFβ1 treatment group, and that the anti-FMT effect of celastrol was significantly weakened after HSP60 knockdown. These results indicated that HSP60 was involved in maintaining the resting state of fibroblasts, and the anti-FMT effect of celastrol was dependent on HSP60. Furthermore, the autophagy promotion and antioxidant effects of celastrol were also weakened after HSP60 knockdown. In conclusion, celastrol inhibits FMT by targeting HSP60, thus exerting anti-pulmonary fibrosis function.
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Pro-inflammatory macrophages play key regulatory role in the occurrence and development of rheumatoid arthritis (RA). In this study, we constructed a celastrol (Cel)-loaded polyamide-amine dendrimer (PAMAM) drug delivery system, which could target folate receptor and mitochondria. It could target inflammatory macrophages and realize chemo-photothermal synergistic therapy. Using PAMAM as the nano-carrier, folate receptor-targeting group folic acid (FA) and mitochondria-targeting group IR808 (also known as the photothermal agent) were conjugated with PAMAM through amide reaction, and then complexed with anti-inflammatory drug Cel to prepare the FA-PAMAM-IR808/Cel nanocomplex. In vitro characterization results showed that the drug loading efficiency of the nanocomplex was 50.90%, particle size was between 130 and 160 nm, average potential was between 1.0 and 3.5 mV, the drug release showed pH sensitivity, temperature reached to 42.5 ℃ after near-infrared (NIR) light irradiation for 10 min. In vitro cellular uptake experiments showed that the nanocomplex had obvious folate receptor-targeting and mitochondria-targeting ability. Following irradiation with NIR light, the cytotoxicity and cellular apoptosis enhanced. The secretion of pro-inflammatory factors tumor necrosis factor α (TNF-α), interleukin (IL)-1β, IL-6 and nitric oxide (NO) decreased in a concentration-dependent manner. This study provided insights for the development of novel anti-RA nanomedicines.
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OBJECTIVE@#To investigate the effect of celastrol on the proliferation and apoptosis of human multiple myeloma (MM) cell lines, reveal the relationship between IRAK4/ERK/p38 signaling pathway and celastrol regulating the proliferation and apoptosis of H929 and ARP-1 cells, and explore whether celastrol combined with bortezomib has synergistic effect. @*METHODS@#CCK-8 method was used to detect the viability of MM cell lines H929 and ARP-1 treated by different concentrations of celastrol, bortezomib, and their combination, and the synergistic effect was determined by Kim's formula. The apoptosis rate of H929 cells and necrosis rate of ARP-1 were detected by Annexin V/PI method. The expression of key proteins and apoptosis proteins in IRAK4/ERK/p38 signaling pathway were detected by Western blot. @*RESULTS@#Celastrol could significantly inhibit the proliferation of H929 and ARP-1 cells (r=0.9018, r=0.9244) and induce apoptosis in a time-dependent manner. Compared with the control group, celastrol could significantly up-regulate the expression of PARP and cleaved caspase-3 while down-regulate the expression of p-IRAK4, p-ERK, and p-p38 in H929 and ARP-1 cells. Celastrol and bortezomib alone inhibited the proliferation of H929 and ARP-1 cells. Compared with celastrol and bortezomib alone, their combination had lower cell survival rate and higher apoptosis rate (P<0.05). @*CONCLUSION@#Celastrol can inhibit the proliferation and promote the apoptosis of H929 and ARP-1 cells, which may be related to inhibiting the phosphorylation of IRAK4 and blocking the activation of IRAK4/ERK/p38 signaling pathway. Celastrol combined with bortezomib has synergistic effect, which can more effectively inhibit the proliferation and induce apoptosis of H929 and ARP-1 cells.
Subject(s)
Humans , Apoptosis , Bortezomib/pharmacology , Cell Line, Tumor , Cell Proliferation , Interleukin-1 Receptor-Associated Kinases , Multiple Myeloma , Pentacyclic Triterpenes , Signal TransductionABSTRACT
Psoriasis is an autoimmune skin disease in which dendritic cells (DCs) trigger the progression of psoriasis by complex interactions with keratinocytes and other immune cells. In the present study, we aimed to load celastrol, an anti-inflammatory ingredient isolated from Chinese herbs, on mannosylated liposomes to enhance DC uptake as well as to induce DC tolerance in an imiquimod-induced psoriasis-like mouse model. Mannose was grafted onto liposomes to target mannose receptors on DCs. The results demonstrated that compared with unmodified liposomes, DCs preferred to take up more fluorescence-labeled mannosylated liposomes. After loading celastrol into mannose-modified liposomes, they effectively inhibited the expression of maturation markers, including CD80, CD86 and MHC-II, on DCs both in vitro and in vivo. Additionally, after intradermal injection with a microneedle, celastrol-loaded mannose-modified liposomes (CEL-MAN-LPs) achieved a superior therapeutic effect compared with free drug and celastrol-loaded unmodified liposomes in the psoriasis mouse model in terms of the psoriasis area and severity index, histology evaluation, spleen weight, and expression of inflammatory cytokines. In conclusion, our results clearly revealed that CEL-MAN-LPs was an effective formulation for psoriasis treatment and suggested that this treatment has the potential to be applied to other inflammatory diseases triggered by activated DCs.
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Objective:To investigate the protective effect and mechanism of celastrol in acute lung injury (ALI) of septic rats.Methods:According to random number table, 24 male Sprague-Dawley (SD) rats were divided into control group (Con group), Sham operation group (Sham group), sepsis-induced ALI group by cecal ligation and perforation (CLP group) and celastrol intervention group (CLP+celastrol group, 2 mg/kg intraperitoneal administration 1 hour before surgery), 6 rats in each group. The abdominal aortic blood of the rats was collected for blood gas analysis 24 hours after the surgery, and then the rats were sacrificed and the lung tissues were taken to calculate the lung wet/dry weight ratio (W/D). The pathological characteristics of lung tissues were observed under light microscope and calculated the lung injury score. The protein levels of Toll-like receptor 4 (TLR4), interleukins (IL-6, IL-10), and nuclear factor-κB (NF-κB) of cytoplasm and nucleus in lung tissues were detected by enzyme linked immunosorbent assay (ELISA).Results:The partial arterial oxygen pressure (PaO 2), lung W/D ratio, lung injury score and the protein levels of inflammatory factor in lung tissues had no differences between Con group and Sham group. Compared with the Con group, PaO 2 in the CLP group was significantly decreased [mmHg (1 mmHg = 0.133 kPa): 60.33±2.01 vs. 109.20±2.99], the lung W/D ratio and lung injury score were significantly increased (lung W/D ratio: 4.44±0.05 vs. 3.27±0.04, lung injury score: 10.67±0.42 vs. 0.50±0.22), and the protein levels of TLR4, IL-6, IL-10 and the nucleus NF-κB in the lung tissues were significantly increased [TLR4 (pg/L): 21.87±0.66 vs. 3.27±0.09, IL-6 (ng/L): 861.10±8.28 vs. 120.30±3.91, IL-10 (ng/L): 212.40±2.57 vs. 41.73±1.02, nuclear NF-κB (ng/L): 707.70±16.82 vs. 403.30±7.46], but the protein level of cytoplasm NF-κB was significantly decreased (ng/L: 213.70±8.67 vs. 408.30±8.71), with statistically significant differences (all P < 0.05). Compared with the CLP group, PaO 2 in CLP+celastrol group was significantly increased (mmHg: 76.83±3.21 vs. 60.33±2.01), the lung W/D ratio and lung injury score were significantly decreased (lung W/D ratio: 3.82±0.03 vs. 4.44±0.05, lung injury score: 5.00±0.37 vs. 10.67±0.42), and the protein levels of TLR4, IL-6, IL-10 and nucleus NF-κB in the lung tissue were significantly decreased [TLR4 (pg/L): 7.57±0.21 vs. 21.87±0.66, IL-6 (ng/L): 380.90±6.55 vs. 861.10±8.28, nuclear NF-κB (ng/L): 533.80±9.42 vs. 707.70±16.82], and the protein level of cytoplasm NF-κB was significantly increased (ng/L: 342.70±14.96 vs. 213.70±8.67), with statistically significant differences (all P < 0.05), while the protein level of IL-10 in lung tissues had no significant difference (ng/L: 210.50±3.16 vs. 212.40±2.57, P > 0.05). Conclusion:Celastrol may regulate the expression and release of inflammatory factors by inhibiting the TLR4/NF-κB pathway, thereby alleviating the ALI induced by sepsis in rats.
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Drug combination can effectively enhance the anti-tumor effect, reduce the drug dose, and improve medication safety. The use of nano-carrier for drug co-delivery can effectively avoid the differences in drug delivery behavior in vivo. Triptolide and celastrol are the main anti-tumor active components of Tripterygium wilfordii Hook f. Modern studies have shown that the combination of triptolide and celastrol can significantly enhance the antitumor effect, but they are limited by poor water solubility and low tumor tissue delivery rate. In this study, a biomimetic erythrocyte membrane liposome co-loaded with triptolide and celastrol was prepared to characterize the morphology, particle size, potential, drug release, serum stability, and other properties. The immunogenicity, uptake behavior, and anti-cell proliferation ability of the biomimetic liposome was compared. All the animal experiments were carried out in accordance with protocol evaluated and approved by the Ethics Committee of Chengdu University of Traditional Chinese Medicine (Chengdu, China). The results showed that the biomimetic erythrocyte membrane liposome co-loaded with triptolide and celastrol (C+T/RBCm@Lip) in this study had an average particle size of 119.12 ± 2.78 nm and a spherical "core-shell" structure. The zeta potential value was -16.9 ± 1.2 mV, and the drug release behavior in vitro was slow. In addition, the process of coating the cell membrane maintained the characteristics of erythrocyte membrane protein, had good stability in serum, and could effectively avoid the recognition and clearance of macrophages, without causing immunogenicity in vivo. The uptake effect of co-loaded biomimetic liposomes on HepG2 hepatocellular carcinoma cells was enhanced compared with that of uncoated cell membrane liposomes, and the inhibitory effect on proliferation of HepG2 cells was enhanced. In conclusion, the biomimetic liposomes coated with erythrocyte membrane prepared in this study is beneficial to the anti-tumor delivery of triptolide and celastrol, and could enhance the inhibitory effect on the growth of HepG2 liver cancer cells, providing a new idea for the anti-tumor application of Tripterygium wilfordii Hook f.
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OBJECTIVE：To study the intervention eff ects and pot ential m echanism of celastrol on non-alcoholic steatohepatitis （NASH）induced by methionine-choline deficiency （MCD）diet. METHODS ：Male C 57BL/6J mice were randomly divided into normal control group ，model group ，celastrol low-dose and high-dose groups [ 0.5，1 mg/（kg·d）]，with 7 mice in each group. The normal control group was given a methionine-choline sufficient diet ，while the model group and administration groups were fed an MCD diet to induce NASH model. At the same time ，normal control group and model group were given polyoxyethylene castor oil intragastrically；administration groups were given relevant drugs intragastrically ；the volume of gavage was 0.1 mL/g，once a day ， for consecutive 4 weeks. The liver morphology was observed ，and the pathological changes of liver tissue were observed by HE staining and oil red O staining. The levels of serum liver enzymes （AST，ALT），and the levels of lipid indexes （TC，TG）in serum and liver tissue were detected by enzyme method. The protein expression of NF-κB p65，TNF-α and IL-6 in liver tissue were determined by Western blotting assay. RESULTS ：Compared with normal control group ，the volume of the liver was reduced and the color was yellow ，and the surface was rough in model group ；inflammatory cell infiltration ，fat vacuoles and lipid droplets aggregation were found in the liver tissue ；the serum levels of TC and TG were significantly decreased ，the levels of serum liver enzymes and protein expression of NF-κB p65，TNF-α and IL-6 in liver tissue were significantly increased （P＜0.01）. Compared with model group ，the liver surface of each administration group was ruddy and smooth without brown spots ，the inflammatory cells and fat vacuoles in liver tissue were reduced ，and the coverage area of lipid droplets was reduced ；the levels of serum TC and TG were significantly increased ，the levels of serum liver enzymes ，the levels of TG and protein expression of NF-κB，TNF-α and IL-6（except for celastrol low-dose group ）in liver tissue were significantly decreased （P＜0.05 or P＜0.01）. CONCLUSIONS ： Celastrol can improve the liver injury of NASH model mice induced by MCD diet ，which is related to the reduction of TG accumulation in liver tissue and inhibition of the expression of inflammatory related factors.
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Metabolic syndrome is a clustering of metabolic disorder with unclear molecular mechanism. Increasing studies have found that the pathogenesis and progression of metabolic syndrome are closely related to inflammation. Here, we report celastrol, a traditional Chinese medicine, can improve high fat diet-induced metabolic syndrome through suppressing resistin-induced inflammation. Mechanistically, celastrol binds to adenylyl cyclase associated protein 1 (CAP1) and inhibits the interaction between CAP1 and resistin, which restrains the cyclic adenylate monophosphate (cAMP)-protein kinase A (PKA)-nuclear factor kappa-B (NF-
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Localized delivery, comparing to systemic drug administration, offers a unique alternative to enhance efficacy, lower dosage, and minimize systemic tissue toxicity by releasing therapeutics locally and specifically to the site of interests. Herein, a localized drug delivery platform ("plum‒pudding" structure) with controlled release and long-acting features is developed through an injectable hydrogel ("pudding") crosslinked
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Objective: To obtain formulations of Celastrol (Cst) nanoemulgel via transdermal route. Celastrol is classified in BCS 4 class as an anti-inflammatory drug. These routes are considered to reduce the risk of Celastrol side effects and have the same characteristics as skin morphology. Methods: Celastrol nanoemulgel was prepared by a high-pressure homogenizer (HPH) technique. To find the optimum nanoemulsion area by using the Chemix 7.00 ternary phase program. Celastrol nanoemulgel was evaluated by measuring the particle size, PDI, morphology, zeta potential, stability tests and in vitro using Franz diffusion cell Results: Results showed the ideal formula based on the ternary phase diagram using chemix 7.00 is oil: smix: water (5:45:50), with particle size 89.9±5 nm, PDI 0.1, and zeta-21 mV. The morphological shape is quite spherical ≤ 100±5 nm. The pH value of this formula is 4.5, which compatible with the pH of the skin. The highest recovery rate of Celastrol and encapsulation efficiency (EE) were formulas 3 μg/ml and 5 μg/ml, with EE 91.70% and 94.54%, respectively. In vitro test results showed that the formula 3 μg/ml and 5 μg/ml give better penetration results than the formula 2.5 μg/ml. Thus, Celastrol nanoemulgel formula has good potential to be developed as a transdermal anti-inflammatory drug. Conclusion: Transdermal nanoemulgel containing Celastrol has been successfully developed with particle size ≤ 200±2 nm.
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OBJECTIVE: To investigate the biomolecular anti-diabetes mechanism and its complications of celastrol based on bioinformatics database. METHODS: The related genes of celastrol were obtained from the bioinformatics database, the cross-related genes of celastrol and diabetes mellitus were searched by Veen diagram software, the protein-protein interaction network was constructed by STRING software, the related KEGG pathway was identified by the DAVID software and KOBAS software, and the molecular network of anti-diabetes "compound-target gene-pathway-disease" was further constructed by R program software. RESULTS: There were 50 genes related to diabetes in celastrol, and 11 related pathways (P<0.001), which mainly affected the AGE-RAGE signaling pathway in diabetic complications. The mechanism was to regulate AGE-RAGE-NF-κB axis by inhibiting NF-κB, which reduced the production of downstream inflammatory effectors, insulin resistance and fibrotic damage. CONCLUSION: Celastrol can improve the symptoms of diabetes and its complications by regulating the AGE-RAGE-NF-κB axis-related signaling pathway, which is expected to be a potential drug for the treatment of diabetes and its complications.
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Obesity is a kind of metabolic disease, which is a major risk factor of heart disease, diabetes mellitus and cancer. In recent years, the US Food and Drug Administration (FDA) has approved a stand of drugs treatment for obesity, including sibutramine, orlistat, belviq and so on,however, side effects may occur after long-term using. Celastrol is a class of pentacyclic triterpenoids extracted from the roots of Tripterygium wilfordii Hook F. It has been found that celastrol has the pharmacological activities of increasing leptin sensitivity, increasing fat metabolism, inhibiting the formation of lipocyte and inhibiting chronic inflammation in obesity animals. This overview summarizes the related mechanisms of celastrol on treatment of obesity to provide enlightenments for its further study.
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OBJECTIVE：To prepar e Celastrol oral u lcer film ，and to evalute its quality primarily. METHODS ：The comprehensive scores of the appearance ，film formation and toughness of the drug film were used as indicators ，and the amount of celastrol was controlled to 0.05％. Orthogonal test was used to optimize the amount of excipients as starch ，sodium carboxymethyl cellulose，glycerol and condensed honey ，so as to optimize the formulation ；the validation test was performed. The adhesion force of the film prepared by the optimal formulation were determined. UV spectrophotometer was used to detect the content of celastrol in the film. RESULTS ：The optimal dosage of each excipient in Celastrol oral ulcer film was starch 1.0 g，sodium carboxymethyl cellulose 0.2 g，glycerin 0.4 g，condensed honey 1.5 g. In 3 times of validation tests ，the appearance of the prepared film was good. The average adhesion of the film prepared by the optimal formulation was 4.2 g，and the average content of celastrol was 0.135 3 mg/cm2（RSD＝1.90％，n＝3）. CONCLUSIONS ：In this study ，the best formulation of Celastrol oral ulcer film was optimized，and the film forming ability of the prepared film is good and the quality is stable and uniform.
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Objective: To investigate the toxicity and mechanisms of celastrol (CEL) on human biliary epithelial cells. Methods: The effects of CEL on cell morphology and cell viability changes were observed by CCK-8 experiment and microscope. Cell scratch experiment was used to detect the effect of CEL on cell migration. The effects of CEL on cell cycle and cell apoptosis were detected by flow cytometry. The mRNA and protein expression of apoptosis-related genes Caspase-3, Bax and Bcl-2 were detected by qRT-PCR and Western blotting. Results: CEL inhibited cell proliferation and changed cell morphology at 400-2 000 nmol/L. At 200-800 nmol/L, cell migration was inhibited. At 800-1 200 nmol/L, G0/G1 phase was arrested. At 400-1 200 nmol/L, cell apoptosis was induced and the expression of apoptosis-related genes was increased. Conclusion: CEL showed cholangiocyte toxicity through affecting cell viability, cell migration, preventing cell cycle and promoting cell apoptosis of human biliary epithelial cells.
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Objective:To investigate the effect of celastrol on painful and the emotional of anxiety and depression comorbidity on neuropathic pain model animal and to explore its possible mechanism．Method:Mice were randomly divided into sham group， model group， pregabalin group(25 mg·kg-1)， low， medium and high-dose celastrol groups (5，10，20 mg·kg-1). The mice model of neuropathic pain were established by the L5 spinal nerve ligation (SNL). After successful modeling， the treatment groups were given intragastric administration， the sham group and the model group were given the same volume of warm water.Mechanical pain were detected by Von Frey tests， anxiety and depression behaviors were separately detected by the open field and the tail tailing experiments， the pathological changes of microglial cells in hippocampus of mice in each group were observed by immunohistochemical staining (IHC). The inflammation of BV2 microglial cell made by 1 mg·L-1 lipopolysaccharide (LPS). Real-time quantitative polymerase chain reaction （Real-time PCR） was used to detect the mRNA expression levels of tumor necrosis factor-α (TNF-α). The expression levels of TNF-α protein were detected by immunofluorescence（IF） staining.Result:Compared with sham group， significant change of mechanical pain thresholds， anxiety and depression were detected in the SNL mice (P<0.05，P<0.01)， the significant decreases of the body size of hippocampal microglia (P<0.05). Compared with SNL model group， 20 mg·kg-1 celastrol significantly increased the 50% paw withdraw threshold and the time of the open feld tests (P<0.05，P<0.01)，and decreased the time of the tail tailing experiments in the SNL mice (P<0.05)， and the cell body area of hippocampal microglia in SNL mice was reduced (P<0.05). Experiment in vitro show， compared with control group， the expression of TNF-α mRNA and protein expression in LPS-induced BV2 microglia increased significantly from 2-4 h (P<0.05，P<0.01). Compared with the LPS group， after 100 nmol·L-1 celastrol administration， LPS-induced microglia inflammatory factor TNF-α mRNA and TNF-α protein expression were significantly decreased (P<0.01).Conclusion:Celastrol can relieve pain-emotion comorbidity on neuropathic pain model mice， and its mechanism may be related to the anti-inflammation in the central nerves system.
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@#To study the inhibitory effect of celastrol respectively combined with glycyrrhetic acid, paclitaxel, and rhein on the proliferation of human hepatoma cell line HepG2. The MTT method was used to detect the survival rate of HepG2 cells. The cooperativity index(CI)and Jin′s formula method were used to determine the synergistic effect. Apoptosis and cell cycle arrest were detected, too. The results show that celastrol, glycyrrhetinic acid, rhein, and paclitaxel alone can inhibit the proliferation of HepG2 cells, respectively. Combination with glycyrrhetic acid, paclitaxel, and rhein, respectively, the inhibitory effect of celastrol on the proliferation of HepG2 cells was significantly enhanced. And the synergistic effect on the proliferation inhibition of HepG2 cells in some concentrations was displayed in the experiment. The cell apoptosis rate was improved(P< 0. 01)and more cells were arrested in G2/M phase. Celastrol respectively combined with glycyrrhetic acid, paclitaxel, and rhein displayed a synergistic inhibitory effect on the proliferation of HepG2 cells, and the effect was related to inducing cell apoptosis and increasing the cell cycle arrest in G2/M phase.
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Objective: To investigate the relationship between celastrol inhibition against multiple myeloma cell growth and unfolded protein response (UPR) and the related molecular mechanism, so as to provide new drug targets for multiple myeloma treatment. Methods: Four multiple myeloma cell lines RPMI 8226, U266, SKO and KMS-11 were treated with different concentrations (proliferation: 0.0-10.0 μmol/L; apoptosis: 0.0-4.0 μmol/L; cell cycle: 0.0-1.5 μmol/L) of celastrol for different periods (proliferation: 1-3 d; apoptosis: 1 d; cell cycle: 1 d), and cell proliferation, apoptosis and cell cycle were examined. Western blotting analysis was used to detect the main molecules in the inositol-requiring enzyme 1 (IRE1), PRKR-like endoplasmic reticulum kinase (PERK), and activating transcription factor 6 (ATF6) signaling pathways of UPR, which included glucose-regulated protein 78 (GRP78), ATF6, PERK, eukaryotic initiation factor 2α (eIF2α), phosphorylated-eIF2α (p-eIF2α), C/EBP homologous protein (CHOP), IRE1 and phosphorylated-IRE1 (p-IRE1). After the lentivirus vector containing short hairpin RNA (shRNA) was used to interfere with eIF2α expression in RPMI 8226 cells, the effects of celastrol were detected on signaling molecule expression, apoptosis and cell cycle. Results: Celastrol inhibited the proliferation of 4 multiple myeloma cells, induced apoptosis, and arrested the cell cycle at G0/G1 phase in dose- and time-dependent manners. RPMI 8226 cells were most sensitive to celastrol. For RPMI 8226 cells, when 0.5-2.0 μmol/L of celastrol was used for 30 min to 24 h, the p-eIF2α levels in the PERK signaling pathway of UPR were significantly increased (P<0.05 or P<0.01), and the downstream CHOP expression was risen correspondingly (P<0.05 or P<0.01), but the other two pathways ATF6 and IRE1 were not affected obviously. After interference of eIF2α expression with lentivirus vector containing shRNA, the effects of celastrol to increase CHOP expression, induce apoptosis and arrest cell cycle were significantly attenuated or disappeared. Conclusion: Celastrol can inhibit the growth of a variety of multiple myeloma cells, and the activated eIF2α molecule in the UPR PERK signaling pathway may be one of the mechanisms.
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Objective To verify the synergistic effect of transferrin modified β-elemene and celastrol co-loaded microemulsion (Tf-EC-MEs) on anti-colorectal cancer treatment. Methods The optimal mass ratio of β-elemene and celastrol to growth inhibition of Lovo and HT-29 colorectal cancer cells was optimized by MTT staining method in vitro. Tf-EC-MEs was prepared by “mixing-dripping” method, and the preparation and physicochemical properties of the particles were characterized by high performance liquid chromatography (HPLC), laser particle analyzer, and transmission electron microscope. The MTT staining, HPLC-BCA combined method, and Annexin V-PE/7-Aminoactinomycin D (Annexin V-PE/7-AAD) kit were used to investigate the antitumor activity of Tf-EC-MEs in vitro, and its effect on cell uptake, and apoptosis of tumor cells. The tumor-bearing nude mice model was established by subcutaneous injection of Lovo cells, and the tumor growth, weight, and survival time were observed after intravenous injection of β-elemene + celastrol, β-elemene-celastrol co-loaded microemulsion (EC-MEs), and Tf-EC-MEs. Results The combined administration of β-elemene and celastrol (40:1) had significant synergistic effect on the anti-colorectal cancer of Lovo and HT-29 cells. IC50 of β-elemene + celastrol in Lovo and HT-29 cells were (17.5 ± 2.9) and (36.4 ± 3.6) μg/mL, with the CI as 0.89 and 0.96, respectively. IC50 of Tf-EC-MEs in Lovo and HT-29 cells were (11.7 ± 0.6) and (27.4 ± 1.2) μg/mL, with the CI as 0.61 and 0.72 respectively. The 4 h of Lovo uptake of Tf-EC-MEs was 7.2 μg/mg, which was 3.3 times higher than that of β-elemene + celastrol. Tf-EC-MEs induced apoptosis in 59.2% of Lovo cells, which was significantly higher than that in beta-elemene + celastrol and EC-MEs groups. Tf-EC-MEs showed the overwhelming inhibition of growth of Lovo tumor-bearing tumors. The survival rate of Tf-EC-MEs-treated mice was 37.5% at day 60. In Tf-EC-MEs treated group, HE staining sections of tumor tissues showed substantial cell necrosis and the Ki-67 immunohistochemical sections displayed the significant inhibition of proliferation of tumor cells. Conclusion Compared with the combination group (beta-elemene and celastrol) and EC-MEs groups, Tf-EC-MEs has a promising potential in the synergistic anti-colorectal cancer treatment.
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Objective To study the intestinal absorption kinetics of Tripterygium wilfordii (TW) solid dispersions and the effects of different intestinal segments, drug concentrations, pH value, and P-glycoprotein (P-gp) on intestinal absorption. Methods The absorption behavior was investigated in situ with a single-pass intestinal perfusion (SPIP) model in rats. The content of each index component was determined by HPLC. The gravimetric method was used to correct the data and calculate the absorption rate constant (Ka) and apparent permeability coefficient (Papp) of each index component. Results The index components of TW were absorbed in the whole intestine, and the absorption rate constant (Ka) of all the index components of TW solid dispersion was significantly increased than that of extract (P < 0.05), and had some differences among different segments. With the increase of drug concentration, the absorption of each index component had saturation phenomenon, which indicated that it may be carrier-mediated transport mechanism. Acidic environment (pH 5.4) was beneficial to the absorption of various index components, especially the acidic content celastrol. After adding P-gp inhibitor, the Ka and Papp of celastrol were significantly different from those without P-gp inhibitor (P < 0.05), which suggested that it may be the P-gp substrate. Conclusion All the index components of TW solid dispersion are absorbed in the whole intestine and have saturation phenomenon, which suggested the absorption may be carrier-mediated transport mechanism. Acidic environment is beneficial to the absorption of all components. The absorption process of celastrol is affected by drug concentration and P-gp inhibitor, which indicated that it may be P-gp substrate. The preparation of solid dispersing can significantly enhance the absorption of various components of TW, suggesting that all the index components are BCS II drugs, and the bioavailability of the preparation may be improved.