ABSTRACT
The transcription factor STAT3 is a promising target for the treatment of non-small cell lung cancer (NSCLC). STAT3 activity is mainly dependent on phosphorylation at tyrosine 705 (pSTAT3-Y705), but the modulation on pSTAT3-Y705 is elusive. By screening a library of deubiquitinases (Dubs), we found that the Otub1 increases STAT3 transcriptional activity. As a Dub, Otub1 binds to pSTAT3-Y705 and specifically abolishes its K48-linked ubiquitination, therefore preventing its degradation and promoting NSCLC cell survival. The Otub1/pSTAT3-Y705 axis could be a potential target for the treatment of NSCLC. To explore this concept, we screen libraries of FDA-approved drugs and natural products based on STAT3-recognition element-driven luciferase assay, from which crizotinib is found to block pSTAT3-Y705 deubiquitination and promotes its degradation. Different from its known action to induce ALK positive NSCLC cell apoptosis, crizotinib suppresses ALK-intact NSCLC cell proliferation and colony formation but not apoptosis. Furthermore, crizotinib also suppresses NSCLC xenograft growth in mice. Taken together, these findings identify Otub1 as the first deubiquitinase of pSTAT3-Y705 and provide that the Otub1/pSTAT3-Y705 axis is a promising target for the treatment of NSCLC.
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BACKGROUND: Carnosine, a natural bioactive dipeptide derived from meat muscle, possesses strong antioxidant properties. Dexamethasone, widely employed for treating various inflammatory diseases, raises concerns regarding its detrimental effects on bone health. This study aimed to investigate the protective effects of carnosine against dexamethasone-induced oxidative stress and bone impairment, along with its underlying mechanisms, utilizing chick embryos and a zebrafish model in vivo, as well as MC3T3-E1 cells in vitro. RESULTS: Our findings revealed that carnosine effectively mitigated bone injury in dexamethasone-exposed chick embryos, accompanied by reduced oxidative stress. Further investigation demonstrated that carnosine alleviated impaired osteoblastic differentiation in MC3T3-E1 cells and zebrafish by suppressing the excessive production of reactive oxygen species (ROS) and enhancing the activity of antioxidant enzymes such as superoxide dismutase (SOD) and glutathione peroxidase (GPX). Moreover, mechanistic studies elucidated that carnosine promoted the expression and nuclear translocation of nuclear factor erythroid 2-related factor 2 (NRF2), thereby facilitating the transcription of its downstream antioxidant response elements, including heme oxyense-1 (HO-1), glutamate cysteine ligase modifier (GCLM), and glutamate cysteine ligase catalytic (GCLC) to counteract dexamethasone-induced oxidative stress. CONCLUSION: Overall, this study underscores the potential therapeutic efficacy of carnosine in mitigating oxidative stress and bone damage induced by dexamethasone exposure, shedding light on its underlying mechanism of action by activating the NRF2 signaling pathway. © 2024 Society of Chemical Industry.
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OBJECTIVE: This systematic review and meta-analysis study aimed to evaluate the effectiveness of probiotics supplementation on glycaemic control in patients with type 2 diabetes mellitus (T2DM) based on the data from the randomised clinical trials (RCTs). METHODS: PubMed, Web of Sciences, Embase, and Cochrane Library were searched from the inception to October 2022, and RCTs about probiotics and T2DM were collected. The standardised mean difference (SMD) with 95% confidence interval (CI) was used to estimate the effects of probiotics supplementation on glycaemic control related parameters, e.g. fasting blood glucose (FBG), insulin, haemoglobin A1c (HbA1c), and homeostasis model of assessment of insulin resistance (HOMA-IR). RESULTS: Thirty RCTs including 1,827 T2MD patients were identified. Compared with the placebo group, the probiotics supplementation group had a significant decrease in the parameters of glycaemic control, including FBG (SMD = - 0.331, 95% CI - 0.424 to - 0.238, Peffect < 0.001), insulin (SMD = - 0.185, 95% CI - 0.313 to - 0.056, Peffect = 0.005), HbA1c (SMD = - 0.421, 95% CI - 0.584 to - 0.258, Peffect < 0.001), and HOMA-IR (SMD = - 0.224, 95% CI - 0.342 to - 0.105, Peffect < 0.001). Further subgroup analyses showed that the effect was larger in the subgroups of Caucasians, high baseline body mass index (BMI ≥ 30.0 kg/m2), Bifidobacterium and food-type probiotics (Psubgroup < 0.050). CONCLUSION: This study supported that probiotics supplementation had favourable effects on glycaemic control in T2DM patients. It may be a promising adjuvant therapy for patients with T2DM.
Subject(s)
Diabetes Mellitus, Type 2 , Insulin Resistance , Probiotics , Adult , Humans , Glycated Hemoglobin , Blood Glucose , Glycemic Control , Diabetes Mellitus, Type 2/drug therapy , Probiotics/therapeutic use , Probiotics/pharmacology , Insulin/therapeutic use , Randomized Controlled Trials as TopicABSTRACT
Proteasomes are overexpressed in multiple myeloma (MM) and proteasomal inhibitors (PIs) have been widely used for the treatment of MM. PIs are reported to induce MM cell apoptosis but impair necroptosis. In the present study, we found that PIs MG132 and bortezomib induce MM cell pyroptosis, a novel type of cell death, in a GSDME-dependent manner. Lack of GSDME totally blocks PI-induced pyroptosis. Interestingly, we found that Caspase-3/6/7/9 are all involved in pyroptosis triggered by PIs because the specific inhibitor of each caspase ablates GSDME activation. PIs markedly reduce mitochondrial membrane potential. Moreover, PIs disrupt the interaction of Bcl-2 and BAX, induce cytochrome c release from mitochondria to cytosol and activate GSDME. Furthermore, we found that overexpression of an N-terminal portion of GSDME suffices to release cytochrome c from mitochondria and to activate Caspase-3/9, suggesting N-GSDME might penetrate the mitochondrial membrane. Consistent with Bcl-2 inhibition, BAX can induce MM cell pyroptosis in a GSDME-dependent manner. In accordance with these findings, inhibition of Bcl-2 synergizes with PIs to induce MM cell pyroptosis. Therefore, the present study indicates that PIs trigger MM cell pyroptosis via the mitochondrial BAX/GSDME pathway and provides a rationale for combined treatment of MM with Bcl-2 and proteasome inhibitors to increase therapeutic efficiency via induction of pyroptosis.
Subject(s)
Multiple Myeloma , Pyroptosis , Humans , Pyroptosis/physiology , Proteasome Inhibitors/pharmacology , bcl-2-Associated X Protein/metabolism , Caspase 3/metabolism , Multiple Myeloma/drug therapy , Cytochromes c/metabolismABSTRACT
The cell cycle regulator cyclin D3 (CCND3) is highly expressed in multiple myeloma (MM) and it promotes MM cell proliferation. After a certain phase of cell cycle, CCND3 is rapidly degraded, which is essential for the strict control of MM cell cycle progress and proliferation. In the present study, we investigated the molecular mechanisms regulating CCND3 degradation in MM cells. By utilizing affinity purification-coupled tandem mass spectrometry, we identified the deubiquitinase USP10 interacting with CCND3 in human MM OPM2 and KMS11 cell lines. Furthermore, USP10 specifically prevented CCND3 from K48-linked polyubiquitination and proteasomal degradation, therefore enhancing its activity. We demonstrated that the N-terminal domain (aa. 1-205) of USP10 was dispensable for binding to and deubiquitinating CCND3. Although Thr283 was important for CCND3 activity, it was dispensable for CCND3 ubiquitination and stability modulated by USP10. By stabilizing CCND3, USP10 activated the CCND3/CDK4/6 signaling pathway, phosphorylated Rb, and upregulated CDK4, CDK6 and E2F-1 in OPM2 and KMS11 cells. Consistent with these findings, inhibition of USP10 by Spautin-1 resulted in accumulation of CCND3 with K48-linked polyubiquitination and degradation that synergized with Palbociclib, a CDK4/6 inhibitor, to induce MM cell apoptosis. In nude mice bearing myeloma xenografts with OPM2 and KMS11 cells, combined administration of Spautin-l and Palbociclib almost suppressed tumor growth within 30 days. This study thus identifies USP10 as the first deubiquitinase of CCND3 and also finds that targeting the USP10/CCND3/CDK4/6 axis may be a novel modality for the treatment of myeloma.
Subject(s)
Multiple Myeloma , Mice , Animals , Humans , Cyclin D3 , Multiple Myeloma/metabolism , Mice, Nude , Apoptosis , Deubiquitinating Enzymes , Cell Line, Tumor , Ubiquitin Thiolesterase/metabolismABSTRACT
The PTEN/AKT/mTOR signaling pathway is frequently dysregulated in non-small cell lung cancer (NSCLC), but the mechanisms are not well-understood. The present study found that the ubiquitin ligase TRIM25 is highly expressed in NSCLC tissues and promotes NSCLC cell survival and tumor growth. Mechanistic studies revealed that TRIM25 binds to PTEN and mediates its K63-linked ubiquitination at K266. This modification prevents the plasma membrane translocation of PTEN and reduces its phosphatase activity therefore accumulating PI(3,4,5)P3. TRIM25 thus activates the AKT/mTOR signaling. Moreover, we found that the antibacterial nitroxoline can activate PTEN by reducing its K63-linked polyubiquitination and sensitizes NSCLC to cisplatin-induced apoptosis. This study thus identified a novel modulation on the PTEN signaling pathway by TRIM25 and provides a potential target for NSCLC treatment.
Subject(s)
Carcinoma, Non-Small-Cell Lung/pathology , DNA-Binding Proteins/metabolism , Lung Neoplasms/pathology , PTEN Phosphohydrolase/metabolism , Proto-Oncogene Proteins c-akt/metabolism , TOR Serine-Threonine Kinases/metabolism , Apoptosis/drug effects , Cell Line, Tumor , Cisplatin/pharmacology , Humans , Nitroquinolines/pharmacology , Phosphoric Monoester Hydrolases/physiology , RNA, Small Interfering/metabolism , Ubiquitination/physiologyABSTRACT
Recent studies show that the expression of CCND1, a key factor in cell cycle control, is increased following the progress and deteriotation of glioma and predicts poor outcomes. On the other hand, dysregulated deubiquitinase USP10 also predicts poor prognosis for patients with glioblastoma (GBM). In the present study, we investigated the interplay between CCND1 protein and USP10 in GBM cells. We showed that the expression of CCND1 was significantly higher in both GBM tissues and GBM-derived stem cells. USP10 interacted with CCND1 and prevented its K48- but not K63-linked polyubiquitination in GBM U251 and HS683 cells, which led to increased CCND1 stability. Consistent with the action of USP10 on CCND1, knockdown of USP10 by single-guided RNA downregulated CCND1 and caused GBM cell cycle arrest at the G1 phase and induced GBM cell apoptosis. To implement this finding in the treatment of GBMs, we screened a natural product library and found that acevaltrate (AVT), an active component derived from the herbal plant Valeriana jatamansi Jones was strikingly potent to induce GBM cell apoptosis, which was confirmed by the Annexin V staining and activation of the apoptotic signals. Furthermore, we revealed that AVT concentration-dependently suppressed USP10-mediated deubiquitination on CCND1 therefore inducing CCND1 protein degradation. Collectively, the present study demonstrates that the USP10/CCND1 axis could be a promising therapeutic target for patients with GBMs.
Subject(s)
Cyclin D1/metabolism , Glioblastoma/metabolism , Iridoids/pharmacology , Ubiquitin Thiolesterase/metabolism , Ubiquitination/physiology , Apoptosis/drug effects , Cell Line, Tumor , Cell Proliferation/physiology , Glioblastoma/drug therapy , HEK293 Cells , Humans , Ubiquitin Thiolesterase/antagonists & inhibitors , Ubiquitination/drug effectsABSTRACT
RNF6, a RING-type ubiquitin ligase, has been identified as an oncogene in various cancers but its role in multiple myeloma (MM) remains elusive. In the present study we first showed that the expression levels of RNF6 in MM were significantly elevated compared with the bone marrow cells of healthy donors. Overexpression of RNF6 in LP1 and PRMI-8266 MM cell lines promoted cell proliferation, whereas knockdown of RNF6 led to apoptosis of MM cells. Furthermore, we revealed that RNF6, as a ubiquitin ligase, interacted with glucocorticoid receptor (GR) and induced its K63-linked polyubiquitination. Different from current knowledge, RNF6 increased GR stability at both endogenous and exogenous contexts. Such an action greatly promoted GR transcriptional activity, which was confirmed by luciferase assays and by the increased expression levels of prosurvival genes including Bcl-xL and Mcl-1, two typical downstream genes of the GR pathway. Consistent with these findings, ectopic expression of RNF6 in MM cells conferred resistance to dexamethasone, a typical anti-myeloma agent. In conclusion, we demonstrate that RNF6 promotes MM cell proliferation and survival by inducing atypical polyubiquitination to GR, and RNF6 could be a promising therapeutic target for the treatment of MM.
Subject(s)
DNA-Binding Proteins/metabolism , Multiple Myeloma/metabolism , Receptors, Glucocorticoid/metabolism , Cell Proliferation , Cell Survival , Cells, Cultured , DNA-Binding Proteins/genetics , Dose-Response Relationship, Drug , Humans , Molecular Structure , Multiple Myeloma/pathology , Receptors, Glucocorticoid/genetics , Structure-Activity Relationship , UbiquitinationABSTRACT
c-Maf is a critical oncogenic transcription factor that contributes to myelomagenesis. Our previous studies demonstrated that the deubiquitinase USP5 stabilizes c-Maf and promotes myeloma cell proliferation and survival; therefore, the USP5/c-Maf axis could be a potential target for myeloma therapy. As a concept of principle, the present study established a USP5/c-Maf-based luciferase system that was used to screen an FDA-approved drug library. It was found that mebendazole, a typical anthelmintic drug, preferentially induced apoptosis in c-Maf-expressing myeloma cells. Moreover, oral administration of mebendazole delayed the growth of human myeloma xenografts in nude mice but did not show overt toxicity. Further studies showed that the selective antimyeloma activity of mebendazole was associated with the inhibition of the USP5/c-Maf axis. Mebendazole downregulated USP5 expression and disrupted the interaction between USP5 and c-Maf, thus leading to increased levels of c-Maf ubiquitination and subsequent c-Maf degradation. Mebendazole inhibited c-Maf transcriptional activity, as confirmed by both luciferase assays and expression measurements of c-Maf downstream genes. In summary, this study identified mebendazole as a USP5/c-Maf inhibitor that could be developed as a novel antimyeloma agent.
Subject(s)
Antineoplastic Agents/therapeutic use , Mebendazole/therapeutic use , Multiple Myeloma/drug therapy , Proto-Oncogene Proteins c-maf/metabolism , Ubiquitin-Specific Proteases/metabolism , Animals , Apoptosis/drug effects , Cell Line, Tumor , Cyanoacrylates/therapeutic use , Drug Repositioning , Drug Synergism , Female , HEK293 Cells , Humans , Mice, Inbred BALB C , Mice, Nude , Multiple Myeloma/metabolism , Proof of Concept Study , Protein Binding/drug effects , Proto-Oncogene Proteins c-maf/chemistry , Pyridines/therapeutic use , Ubiquitin-Specific Proteases/chemistry , Ubiquitination/drug effects , Xenograft Model Antitumor AssaysABSTRACT
Interferon-α (IFN-α) inhibits tumor growth and mimics graft-versus-leukemia after allogeneic hematopoietic stem cell transplantation (allo-HSCT). In the current case-control study, we compared treatment responses in acute leukemia patients with relapse tendency post-allo-HSCT receiving preemptive IFN-α after withdrawal of immunosuppressants (n = 31) vs. receiving no IFN-α (n = 67). In the IFN-α group, 25 patients responded to the treatment without progressing to hematological relapse. In the non-IFN-α group, only 22 patients responded to the treatment. The response rate differed significantly (80.6 vs. 32.8%, P < 0.001). The 2-year cumulative incidence of relapse was 31.6 and 61.2% in the IFN-α and the non-IFN groups, respectively (P = 0.006). The 2-year leukemia-free survival and overall survival rate was 57.4 vs. 28.4% (P < 0.001) and 67.6 vs. 32.9% (P = 0.001), respectively. Among the 31 patients in the IFN-α group, 18 patients (58.1%) developed graft-versus-host disease (GVHD): 6 acute and 12 limited chronic GVHD. Patients who developed GVHD had higher treatment response rate than patients without GVHD (88.9 vs. 53.8%, P = 0.022). In conclusion, preemptive IFN-α therapy is a safe and effective treatment to prevent disease progression in high-risk patients with relapse tendency post-allo-HSCT.
Subject(s)
Hematopoietic Stem Cell Transplantation , Interferon-alpha/administration & dosage , Leukemia , Acute Disease , Adolescent , Adult , Allografts , Child , Chronic Disease , Disease-Free Survival , Female , Graft vs Host Disease/etiology , Graft vs Host Disease/mortality , Graft vs Host Disease/pathology , Humans , Leukemia/mortality , Leukemia/pathology , Leukemia/therapy , Male , Middle Aged , Recurrence , Survival RateABSTRACT
The signal transducer and activator of transcription 3 (STAT3) plays a critical role in platelet functions. This study sought to understand the effects of the STAT3 inhibitor SC99 on platelet activation and aggregation. Immunoblotting assays were applied to measure the effects of SC99 on the STAT3 signaling pathway. A ChronoLog aggregometer was used to evaluate platelet aggregation. A flow cytometer was used to evaluate P-selectin expression in the presence of SC99. AlamarBlue and Annexin-V staining were used to evaluate platelet viability and apoptosis, respectively. A fluorescence microscope was applied to analyze platelet spreading. SC99 inhibited the phosphorylation of JAK2 and STAT3 in human platelets but had no effects on the phosphorylation of AKT, p65 or Src, all of which are involved in platelet activation. Further studies revealed that SC99 inhibited human platelet aggregation induced by collagen and thrombin in a dose-dependent manner. SC99 inhibited thrombin-induced P-selectin expression and fibrinogen binding to single platelets. Moreover, SC99 inhibited platelet spreading on fibrinogen and clot retraction mediated by outside-in signaling. SC99 inhibited platelet aggregation in mice but it did not significantly prolong the bleeding time. Taken together, the present study revealed that SC99 inhibited platelet activation and aggregation as a STAT3 inhibitor. This agent can be developed as a promising treatment for thrombotic disorders.
Subject(s)
Hydrazones/pharmacology , Platelet Activation/drug effects , Platelet Aggregation Inhibitors/pharmacology , Platelet Aggregation/drug effects , STAT3 Transcription Factor/antagonists & inhibitors , Animals , Bleeding Time , Clot Retraction/drug effects , Humans , Hydrazones/toxicity , Mice, Inbred C57BL , Platelet Aggregation Inhibitors/toxicity , Signal TransductionABSTRACT
Dyslipidemia and hepatic steatosis are the characteristics of the initial stage of nonalcohol fatty liver disease (NAFLD), which can be reversed by lifestyle intervention, including dietary supplementation. However, such commercial dietary supplements with solid scientific evidence and in particular clear mechanistic elucidation are scarce. Here, the health benefits of MHP, a commercial mulberry and Hippophae-based solid beverage, were evaluated in NAFLD rat model and the underlying molecular mechanisms were investigated. Histopathologic examination of liver and white adipose tissue found that MHP supplementation reduced hepatic lipid accumulation and adipocyte hypertrophy. Serum biochemical results confirmed that MHP effectively ameliorated dyslipidemia and decreased circulation-free fatty acid level. RNA-Seq-based transcriptomic analysis showed that MHP-regulated genes are involved in the inhibition of lipolysis of adipose tissue and thus may contribute to the reduction of hepatic ectopic lipid deposition. Furthermore, MHP upregulated ACSL1-CPT1a-CPT2 pathway, a canonical pathway that regulated mitochondrial fatty acid metabolism, and promoted liver and adipose tissue fatty acid ß-oxidation. These results suggest that adipose tissue-liver crosstalk may play a key role in maintaining glucose and lipid metabolic hemostasis. In addition, MHP can also ameliorate chronic inflammation through regulating the secretion of adipokines. Our study demonstrates that MHP is able to improve dyslipidemia and hepatic steatosis through crosstalk between adipose tissue and liver and also presents transcriptomic evidence to support the underlying mechanisms of action, providing solid evidence for its health claims.
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Obesity, a multifactorial disease with many complications, has become a global epidemic. Weight management, including dietary supplementation, has been confirmed to provide relevant health benefits. However, experimental evidence and mechanistic elucidation of dietary supplements in this regard are limited. Here, the weight loss efficacy of MHP, a commercial solid beverage consisting of mulberry leaf aqueous extract and Hippophae protein peptides, was evaluated in a high-fat high-fructose (HFF) diet-induced rat model of obesity. Body component analysis and histopathologic examination confirmed that MHP was effective to facilitate weight loss and adiposity decrease. Pathway enrichment analysis with differential metabolites generated by serum metabolomic profiling suggests that PPAR signal pathway was significantly altered when the rats were challenged by HFF diet but it was rectified after MHP intervention. RNA-Seq based transcriptome data also indicates that MHP intervention rectified the alterations of white adipose tissue mRNA expressions in HFF-induced obese rats. Integrated omics reveals that the efficacy of MHP against obesogenic adipogenesis was potentially associated with its regulation of PPARγ and FGFR1 signaling pathway. Collectively, our findings suggest that MHP could improve obesity, providing an insight into the use of MHP in body weight management.
Subject(s)
Hippophae , Morus , Rats , Animals , PPAR gamma/genetics , PPAR gamma/metabolism , Hippophae/metabolism , Morus/metabolism , Diet, High-Fat/adverse effects , Obesity/metabolism , Adipose Tissue, White/metabolism , Signal Transduction , Weight LossABSTRACT
(1) Background: Optimal bone mass accumulation during adolescence is crucial for maximising peak bone mass during adulthood. Dietary antioxidant vitamins may contribute to bone mass accumulation. This 2.5-year-long longitudinal study aimed to evaluate the relationships between dietary vitamin A, C, and E intakes and the annual changes in bone parameters among Chinese adolescents. (2) Method: Subjects aged 10-18 years (n = 1418) were recruited from a secondary school in Jiangmen, China. Dietary vitamin A, C, and E intakes were assessed using 24 h dietary records over 3 consecutive days. The Sahara Clinical Bone Sonometer was used to measure the broadband ultrasound attenuation (BUA) and the speed of sound (SOS). Their annual changes were then calculated (i.e., BUA%/year, SOS%/year). The associations were detected after adjusting for the baseline bone phenotype; age; sex; weight; height; pubertal stage; physical activity; and dietary intakes of vitamin D, calcium and energy. (3) Results: A curvilinear relationship was found between the dietary intake of vitamin C and BUA%/year (p = 0.026); further analyses in the subgroups revealed that this relationship was observed in male adolescents (p = 0.012). A positive association was observed only in boys with a dietary vitamin C intake of ≥159.01 mg/day (ß = 0.395, p = 0.036). Moreover, a linear positive association was shown between the dietary intake of vitamin E and BUA%/year in female adolescents (ß = 0.082, p = 0.033). (4) Conclusion: Our findings indicated that dietary vitamin C intake has a threshold effect on bone mass gain in male adolescents and that dietary vitamin E intake could be a positive predictor of bone mass gain in female adolescents.
Subject(s)
Antioxidants , Calcaneus , Animals , Ascorbic Acid , Bone Density , Calcaneus/diagnostic imaging , Calcium , Eating , Female , Longitudinal Studies , Male , Ultrasonography , Vitamin A , Vitamin D , Vitamin E , VitaminsABSTRACT
OBJECTIVE: To investigate the mechanism of Paris forrestii (Takht.) H. Li (PCT3)-suppressing the proliferation of HL-60, K562, KG-1 and HT-93 cells. METHODS: cute myeloid leukemia cell lines such as HL-60, K562, KG-1 and HT-93 were treated with Paris forrestii (Takht.) H. Li (PCT3) for 24, 48, and 72 h, and MTT assay was employed to determine the cells proliferation. Meanwhile, the apoptosis of K562, HL-60, KG-1 and HT-93 cells were detected by flow cytometry after PCT3 (Control, 4 µg/ml, 8 µg/ml) treated for 24 h and the Western blot was performed to detect the expression of PARP,Caspase-3, MCL-1, BAX, BCL-2, P53, and P27. GAPDH was used as an internal loading control. RESULTS: MTT assay showed that Paris forrestii (Takht.) H. Li (PCT3) significantly inhibited the proliferation of HL-60, K562, KG-1 and HT-93 cells in concentration and time-dependent manners. Compared with the control group, the leukemia cell viabilities were significantly suppressed (r =0.9436; r =0.8623; r =0.9922; r =0.8918). Paris forrestii (Takht.) H. Li (PCT3) induced apoptosis of leukemia cells in a concentration dependent manner, compared with the control group (Pï¼0.05 or Pï¼0.01). Western blot revealed that PARP, a major enzyme in DNA damage repair, and Caspase-3 another one of the major executive apoptotic enzymes were cleaved in cell lines examined, and this cleavage was concentration dependent. Anti-apoptotic proteins such as MCL-1 and BCL-2 were down regulated by Paris forrestii (Takht.) H. Li (PCT3), and Pro-apoptotic protein BAX was upregulated. And the protein of tumor suppressor gene P53 and its downstream signaling protein P27 increased. CONCLUSION: Paris forrestii (Takht.) H. Li (PCT3) can inhibit the proliferation of leukemia cells by activating endogenous apoptosis pathway, and provide a potential new drug selection for clinical treatment of AML leukemia.
Subject(s)
Leukemia, Myeloid, Acute , Apoptosis , Caspase 3 , Cell Line, Tumor , Cell Proliferation , Humans , Melanthiaceae , Proto-Oncogene Proteins c-bcl-2ABSTRACT
Abnormal phosphorylation of tau, one of the most common symptoms of dementia, has become increasingly important in the study of the etiology and development of Alzheimer's disease. Paeoniflorin, the main bioactive component of herbaceous peony, is a monoterpene glycoside, which has been reported to exert beneficial effects on neurodegenerative disease. However, the effect of paeoniflorin on tauopathies remains ambiguous. SH-SY5Y cells were treated with okadaic acid (OA) for 8â¯h to induce tau phosphorylation and no cell death was observed. Optical microscopy results showed that paeoniflorin ameliorated okadaic acid induced morphological changes, including cell swelling and synapsis shortening. Western blotting data illustrated that paeoniflorin reversed okadaic acid induced tau hyperphosphorylation, which was enhanced by inhibiting the activities of calpain, Akt and GSK-3ß. Transmission electron microscopy results showed that paeoniflorin alone can reduce the number of autophagosomes and stabilize the microtubule structure. In addition, calpastain and paeoniflorin enhance the effect of paeoniflorin on stabilizing microtubules. In addition, calpastain markedly enhanced the effect of paeoniflorin on reversing okadaic acid-lowered fluorescence intensity of both MAP-2 and ß III-tubulin, two microtubule-associated proteins. This study shows that paeoniflorin protected SH-SY5Y cells against okadaic acid assault by interfering with the calpain/Akt/GSK-3ß-related pathways, in which autophagy might be involved. Besides, paeoniflorin is found to relieve the stress response of the microtubule structure system caused by okadaic acid treatment. The results presented in this study suggest that paeoniflorin potentially plays an important role in tauopathies.
Subject(s)
Alzheimer Disease/diagnostic imaging , Glucosides/pharmacology , Monoterpenes/pharmacology , Neurons/drug effects , Neuroprotective Agents/pharmacology , tau Proteins/metabolism , Alzheimer Disease/metabolism , Autophagy/drug effects , Autophagy/physiology , Calpain/metabolism , Cell Line, Tumor , Glycogen Synthase Kinase 3 beta/metabolism , Humans , Microtubules/drug effects , Microtubules/metabolism , Neurons/metabolism , Neurons/pathology , Okadaic Acid/toxicity , Phosphorylation , Proto-Oncogene Proteins c-akt/metabolismABSTRACT
AIM: To study the chemical constituents and bioactivity of the seeds of Crataegus pinnatifida. METHODS: The chemical constituents were isolated and purified by macroporous adsorptive resin D101, silica gel, and ODS column chromatography, and preparative HPLC. Their structures were elucidated on the basis of spectroscopic methods. In addition, the cytotoxic activities of compounds 1-4 were investigated on OPM2 and RPMI-8226 cells. RESULTS: Four compounds were obtained and their structures were identified as (7S, 8S)-4-[2-hydroxy-2-(4-hydroxy-3-methoxyphenyl)-1-(hydroxymethyl)ethoxy]-3, 5-dimethoxybenzaldehyde (1), (+)-balanophonin (2), erythro-guaiacylglycerol-ß-coniferyl aldehyde ether (3), buddlenol A (4). CONCLUSION: Compound 1 is a novel norlignan, while compounds 1-4 exhibited marginal inhibition on the proliferation of OPM2 and RPMI-8226 cells.