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1.
Zhongguo Zhen Jiu ; 43(7): 783-92, 2023 Jul 12.
Artigo em Chinês | MEDLINE | ID: mdl-37429658

RESUMO

OBJECTIVE: To observe the effect of Tongdu Tiaoshen (promoting the circulation of the governor vessel and regulating the spirit) electroacupuncture (EA) pretreatment on pyroptosis mediated by peroxisome proliferators-activated receptor γ (PPARγ) of the cerebral cortex in rats with cerebral ischemia reperfusion injury (CIRI) and explore the potential mechanism of EA for the prevention and treatment of CIRI. METHODS: A total of 110 clean-grade male SD rats were randomly divided into a sham-operation group, a model group, an EA group, an EA + inhibitor group and an agonist group, 22 rats in each group. In the EA group, before modeling, EA was applied to "Baihui" (GV 20), "Fengfu" (GV 16) and "Dazhui" (GV 14), with disperse-dense wave, 2 Hz/5 Hz in frequency, 1 to 2 mA in intensity, lasting 20 min; once a day, consecutively for 7 days. On the base of the intervention as the EA group, on the day 7, the intraperitoneal injection with the PPARγ inhibitor, GW9662 (10 mg/kg) was delivered in the EA + inhibitor group. In the agonist group, on the day 7, the PPARγ agonist, pioglitazone hydrochloride (10 mg/kg) was injected intraperitoneally. At the end of intervention, except the sham-operation group, the modified thread embolization method was adopted to establish the right CIRI model in the rats of the other groups. Using the score of the modified neurological severity score (mNSS), the neurological defect condition of rats was evaluated. TTC staining was adopted to detect the relative cerebral infarction volume of rat, TUNEL staining was used to detect apoptosis of cerebral cortical nerve cells and the transmission electron microscope was used to observe pyroptosis of cerebral cortical neural cells. The positive expression of PPARγ and nucleotide-binding to oligomerization domain-like receptor protein 3 (NLRP3) in the cerebral cortex was detected with the immunofluorescence staining. The protein expression of PPARγ, NLRP3, cysteinyl aspartate specific protease-1 (caspase-1), gasdermin D (GSDMD) and GSDMD-N terminal (GSDMD-N) in the cerebral cortex was detected with Western blot. Using the quantitative real-time fluorescence-PCR, the mRNA expression of PPARγ, NLRP3, caspase-1 and GSDMD of the cerebral cortex was detected. The contents of interleukin (IL)-1ß and IL-18 in the cerebral cortex of rats were determined by ELISA. RESULTS: Compared with the sham-operation group, the mNSS, the relative cerebral infarction volume and the TUNEL positive cells rate were increased (P<0.01), pyroptosis was severe, the protein and mRNA expression levels of PPARγ, NLRP3, caspase-1 and GSDMD were elevated (P<0.01); and the protein expression of GSDMD-N and contents of IL-1ß and IL-18 were increased (P<0.01) in the model group. When compared with the model group, the mNSS, the relative cerebral infarction volume and the TUNEL positive cells rate were decreased (P<0.01), pyroptosis was alleviated, the protein and mRNA expression levels of PPARγ were increased (P<0.01), the protein and mRNA expression levels of NLRP3, caspase-1 and GSDMD were decreased (P<0.01), the protein expression of GSDMD-N was reduced (P<0.01); and the contents of IL-1ß and IL-18 were lower (P<0.01) in the EA group and the agonist group; while, in the EA + inhibitor group, the protein expression of PPARγ was increased (P<0.01), the protein and mRNA expression levels of NLRP3 and GSDMD were decreased (P<0.01, P<0.05), the mRNA expression of caspase-1 was reduced (P<0.01); and the contents of IL-1ß and IL-18 were lower (P<0.01). When compared with the EA + inhibitor group, the mNSS, the relative cerebral infarction volume and the TUNEL positive cells rate were decreased (P<0.05, P<0.01), pyroptosis was alleviated, the protein and mRNA expression levels of PPARγ were increased (P<0.01), the protein and mRNA expression levels of NLRP3, caspase-1 and GSDMD were decreased (P<0.01), the protein expression of GSDMD-N was reduced (P<0.01); and the contents of IL-1ß and IL-18 were declined (P<0.01) in the EA group. Compared with the agonist group, in the EA group, the relative cerebral infarction volume and the TUNEL positive cells rate were increased (P<0.05, P<0.01), the mRNA expression of PPARγ was decreased (P<0.01) and the protein expression of GSDMD-N was elevated (P<0.05); and the contents of IL-1ß and IL-18 were higher (P<0.01). CONCLUSION: Tongdu Tiaoshen EA pretreatment can attenuate the neurological impairment in the rats with CIRI, and the underlying mechanism is related to the up-regulation of PPARγ inducing the inhibition of NLRP3 in the cerebral cortex of rats so that pyroptosis is affected.


Assuntos
Eletroacupuntura , PPAR gama , Masculino , Animais , Ratos , Ratos Sprague-Dawley , PPAR gama/genética , Piroptose , Interleucina-18 , Proteína 3 que Contém Domínio de Pirina da Família NLR , Córtex Cerebral , Infarto Cerebral/genética , Infarto Cerebral/terapia , Caspases , RNA Mensageiro
2.
Zhongguo Zhen Jiu ; 43(4): 405-8, 2023 Apr 12.
Artigo em Chinês | MEDLINE | ID: mdl-37068816

RESUMO

Professor HAN Wei 's clinical experience of acupuncture and moxibustion with Tongyang Xingshen (promoting yang and regaining consciousness) for adolescent depressive disorder is introduced. It is believed that the internal causes of adolescent depressive disorder are mostly emotional and physical factors, while the external causes are mainly social factors, and yang-qi stagnation and emotional disorder are the key pathogenesis. The key of acupuncture and moxibustion with Tongyang Xingshen is warming and regulating the governor vessel. The governor vessel acupoints at head, neck and back are selected. At head, Baihui (GV 20) and Yintang (GV 24+) are selected; at neck, Fengfu (GV 16) and Dazhui (GV 14) are selected; at back, Taodao (GV 13), Shenzhu (GV 12), Shendao (GV 11), Zhiyang (GV 9) and Jinsuo (GV 8) are selected. The combination of disease differentiation and syndrome differentiation should be highly valued, and the moxibustion with Tongyang and acupuncture with Xingshen should be used simultaneously, and the strong stimulation is suggested.


Assuntos
Terapia por Acupuntura , Transtorno Depressivo , Moxibustão , Adolescente , Humanos , Pontos de Acupuntura , Exame Físico
3.
J Drug Target ; 31(4): 402-410, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36724823

RESUMO

Rheumatoid arthritis (RA) is a common autoimmune and inflammatory disease. Activated macrophages in arthritic joints play a prominent role in the initiation and persistence of RA. Despite great progress in the clinical treatment of RA, poor response and high discontinuation due to systemic toxicity remain unsolved issues, especially the well-known methotrexate (MTX). Therefore, active targeted delivery of therapeutic drugs to pathogenic cells in arthritic joints is essential to increase in situ activity and decrease systemic toxicity. Here, we developed an MTX-loaded macrophage-targeted nano-emulsion (NE) based on the overexpression of folate receptor (FR) on activated macrophages, the inherent high affinity of FR for folate (FA), as well as the property of MTX and phospholipids to form complexes (MTX@PC). Intravenous injection of DID-labelled MTX@PC-FA NEs into adjuvant-induced arthritis (AIA) mice, in vivo images and flow cytometry results revealed that the NEs were highly targeted to inflamed joints and macrophages, respectively. Therapeutic studies suggested that this strategy was conducive to achieve high efficacy and low toxicity of MTX in the treatment of RA. Our research highlights MTX@PC-FA NEs as a potential treatment option for RA targeting the FR-expressed activated macrophages.


Assuntos
Antirreumáticos , Artrite Reumatoide , Camundongos , Animais , Metotrexato , Fosfolipídeos , Artrite Reumatoide/tratamento farmacológico , Ácido Fólico , Macrófagos
4.
Zhongguo Zhen Jiu ; 42(11): 1240-4, 2022 Nov 12.
Artigo em Chinês | MEDLINE | ID: mdl-36397221

RESUMO

OBJECTIVE: To observe the clinical effect of acupuncture combined with Qingfei Qutan decoction for stroke-associated pneumonia (SAP) with phlegm-heat obstructing lung, and explore its possible mechanism. METHODS: Ninety-nine patients of SAP with phlegm-heat obstructing lung were randomly divided into a combination group (33 cases, 1 case dropped off), a Chinese medication group (33 cases, 1 case dropped off) and an acupuncture group (33 cases, 1 case dropped off). On the basis of routine basic treatment, the patients in the acupuncture group were treated with acupuncture at Tiantu (CV 22), Feishu (BL 13), Taiyuan (LU 9), Sanyinjiao (SP 6), etc., once a day, with an interval of 1 day after continuous 6-day treatment; the patients in the Chinese medication group were treated with Qingfei Qutan decoction, 1 dose per day; the patients in the combination group were treated with acupuncture combined with Qingfei Qutan decoction. Two weeks were taken as a course of treatment, and two courses of treatment were given. Before and after treatment, the clinical pulmonary infection score (CPIS), inflammatory indexes (neutrophil-to-lymphocyte ratio [NLR], procalcitonin [PCT], C-reactive protein [CRP]), cellular immune function (CD+3, CD+4, CD+8 and CD+4/CD+8) were compared in the 3 groups. The clearance of pathogenic bacteria after treatment was observed in the 3 groups. The clinical efficacy of each group was evaluated. RESULTS: After treatment, the CPIS scores, NLR, PCT, CRP and CD+8 in the each group were lower than those before treatment (P<0.05), while the levels of CD+3, CD+4, CD+4/CD+8 were higher than those before treatment (P<0.05). The above indexes in the combination group were better than those in the acupuncture group and the Chinese medication group (P<0.05), and the above indexes in the Chinese medication group were better than those in the acupuncture group (P<0.05). There was no significant difference in the clearance rate of pathogenic bacteria among three groups (P>0.05). The cured and markedly effective rate was 65.6% (21/32) in the combination group, which was higher than 43.8% (14/32) in the Chinese medication group and 18.8% (6/32) in the acupuncture group (P<0.05). The cured and markedly effective rate in the Chinese medication group was higher than that in the acupuncture group (P<0.05). CONCLUSION: Acupuncture combined with Qingfei Qutan decoction could effectively improve the clinical symptoms of SAP patients with phlegm-heat obstructing lung, and the mechanism may be related to enhancing the cellular immune function and reducing the level of inflammatory reaction.


Assuntos
Terapia por Acupuntura , Medicamentos de Ervas Chinesas , Pneumonia , Acidente Vascular Cerebral , Humanos , Temperatura Alta , Medicamentos de Ervas Chinesas/uso terapêutico , Pulmão , Pneumonia/tratamento farmacológico , Pneumonia/etiologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/tratamento farmacológico , Imunidade
5.
Phytomedicine ; 82: 153448, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33421904

RESUMO

BACKGROUND: Acute myeloid leukemia (AML) is a devastating hematologic malignancy with a high mortality. The nuclear receptors Nur77 and NOR-1 are commonly downregulated in human AML blasts and have emerged as key therapeutic targets for AML. METHODS: This study aimed to identify Z-ligustilide (Z-LIG), the main phthalide of Rhizoma Chuanxiong, as a potential agent that can selectively target AML. The anti-AML activity of Z-LIG was evaluated in vitro and in vivo, and the effect and underlying mechanisms of Z-LIG on the restoration of Nur77 and NOR-1 was determined. Moreover, the role of Nur77 and NOR-1 in the regulation of Z-LIG-induced apoptosis and differentiation of AML cells was explored. RESULTS: Z-LIG preferentially inhibited the viability of human AML cells, as well as suppressed the proliferation and colony formation ability. Notably, a concentration-dependent dual effect of Z-LIG was observed in AML cells: inducing apoptosis at relatively high concentrations (25 µM to 100 µM) and promoting differentiation at relatively low concentrations (10 µM and 25 µM). Importantly, Z-LIG restored Nur77 and NOR-1 expression in AML cells by increasing Ace-H3 (lys9/14) enrichment in their promoters. Meanwhile, Z-LIG enhanced the recruitment of p300 and reduced the recruitment of HDAC1, HDAC4/5/7, and MTA1 in the Nur77 promoter and enhanced the recruitment of p-CREB and reduced HDAC1 and HDAC3 in the NOR-1 promoter. Furthermore, Z-LIG-induced apoptosis was shown to be correlated with the mitochondria localization of Nur77/NOR-1 and subsequent Bcl-2 conformational change, converting Bcl-2 from a cyto-protective phenotype into a cyto-destructive phenotype. Z-LIG-promoted differentiation was found to be related to Nur77/NOR-1-mediated myeloid differentiation-associated transcription factors Jun B, c-Jun, and C/EBPß. Finally, silencing of Nur77 and NOR-1 attenuated anti-AML activity of Z-LIG in NOD/SCID mice. CONCLUSIONS: Our study suggests that Z-LIG may serve as a novel bifunctional agent for AML by restoring Nur77/NOR-1-mediated apoptosis and differentiation.


Assuntos
4-Butirolactona/análogos & derivados , Apoptose/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Leucemia Mieloide Aguda/patologia , Proteínas de Membrana Transportadoras/metabolismo , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , 4-Butirolactona/farmacologia , Animais , Humanos , Leucemia Mieloide Aguda/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID
6.
Int J Oncol ; 49(6): 2265-2274, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27748818

RESUMO

Persistent activation of signal transducers and activators of transcription 3 (STAT3) is commonly detected in many types of cancer including pancreatic cancer. Whether STAT3 is activated in stem cell-like pancreatic cancer cells and the effect of STAT3 inhibition, is still unknown. Flow cytometry was used to isolate pancreatic cancer stem-like cells which are identified by both aldehyde dehydrogenase (ALDH)-positive (ALDH+) as well as cluster of differentiation (CD) 44-positive/CD24-positive subpopulations (CD44+/CD24+). STAT3 activation and the effects of STAT3 inhibition by STAT3 inhibitors, LLL12, FLLL32, and Stattic in ALDH+ and CD44+/CD24+ cells were examined. Our results showed that ALDH+ and CD44+/CD24+ pancreatic cancer stem-like cells expressed higher levels of phosphorylated STAT3, an active form of STAT3, compared to ALDH-negative (ALDH-) and CD44-negative/CD24-negative (CD44-/CD24-) pancreatic cancer cells, suggesting that STAT3 is activated in pancreatic cancer stem-like cells. Small molecular STAT3 inhibitors inhibited STAT3 phosphorylation, STAT3 downstream target gene expression, cell viability, and tumorsphere formation in ALDH+ and CD44+/CD24+ cells. Our results indicate that STAT3 is a novel therapeutic target in pancreatic cancer stem-like cells and inhibition of activated STAT3 in these cells by STAT3 inhibitors may offer an effective treatment for pancreatic cancer.


Assuntos
Antraquinonas/farmacologia , Curcumina/análogos & derivados , Células-Tronco Neoplásicas/metabolismo , Neoplasias Pancreáticas/patologia , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/metabolismo , Sulfonamidas/farmacologia , Aldeído Desidrogenase/metabolismo , Antígeno CD24/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Curcumina/farmacologia , Ativação Enzimática , Humanos , Receptores de Hialuronatos/metabolismo , Esferoides Celulares/efeitos dos fármacos , Células Tumorais Cultivadas
7.
Rapid Commun Mass Spectrom ; 30 Suppl 1: 122-7, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27539426

RESUMO

RATIONALE: Aflatoxins (AFTs) are of great concern all over the world. Supercritical fluid chromatography (SFC) has the advantage of fast, high resolution and excellent compatibility with a broad range of organic solvents and samples, thus hyphenating SFC with tandem mass spectrometry (MS/MS) can be used for the easy and fast determination of AFTs in edible oils. METHODS: Edible oil was spiked with isotope-labeled aflatoxin standards, diluted with hexane and extracted with acetonitrile. The extraction was directly loaded to an SFC apparatus and separated on a UPC(2) 2-EP column with CO2 -methanol gradient elution. A post-column make-up flow was introduced to facilitate mass spectrometry performance, and the mixture was analyzed by MS/MS with an electrospray ionization (ESI) source. RESULTS: The SFC conditions including separation column, modifier and sample solvent were optimized, and the four target aflatoxins were baseline separated. The ESI interface parameters were also investigated, implicating the make-up flow as a critical factor for sensitive determination by SFC-MS/MS. The LOQs for the AFTs were 0.05-0.12 µg L(-1) , while the RSDs were lower than 8.5%. CONCLUSIONS: Supercritical fluid chromatography was successfully coupled to tandem mass spectrometry to establish a simple, fast and sensitive method for the analysis of four aflatoxins in edible oil. This shows the combination of SFC-MS/MS has great potential in determination of trace contaminants in food. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Aflatoxinas/análise , Cromatografia com Fluido Supercrítico/métodos , Análise de Alimentos/métodos , Óleos de Plantas/análise , Espectrometria de Massas em Tandem/métodos , Óleo de Milho/análise , Contaminação de Alimentos/análise , Limite de Detecção , Óleo de Amendoim/análise , Sensibilidade e Especificidade
8.
Oncotarget ; 6(13): 10940-9, 2015 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-25883212

RESUMO

The constitutive activation of signal transducer and activator of transcription 3 (STAT3) is frequently detected in clinical incidences of hepatocellular carcinoma (HCC) but not in normal human hepatocytes. STAT3 signaling plays pivotal roles in angiogenesis, survival, metastasis, and growth of HCC. Recent evidence suggests that the blockade of aberrant STAT3 pathways can be exploited as a therapeutic strategy for HCC. We have developed the novel small molecular STAT3 inhibitor LLL12 on the basis of curcumin structure using computer-aided rational design. LLL12 has shown antitumor activity in various solid tumors including breast, brain, pancreatic cancer, and glioblastoma in vitro and in vivo. In this study, we hypothesized LLL12 inhibits STAT3 phosphorylation at tyrosine 705 (Y705) in HCC and show antitumor activity in HCC in vitro and in vivo. Our results show that LLL12 selectively inhibited HCC cell proliferation and induced apoptosis in SNU387, SNU398, SNU449, and Hep3B HCC cells in vitro. Furthermore, LLL12 at 5 mg/kg/day significantly inhibited the growth of SNU398 xenografts in nude mice. Collectively, our results indicate that LLL12 could be used to target STAT3 for the effective prevention or treatment of HCC.


Assuntos
Antraquinonas/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Neoplasias Hepáticas/tratamento farmacológico , Fator de Transcrição STAT3/antagonistas & inibidores , Sulfonamidas/farmacologia , Animais , Western Blotting , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Ciclo Celular/efeitos dos fármacos , Feminino , Citometria de Fluxo , Imunofluorescência , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Nus , Fosforilação/efeitos dos fármacos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Acta Biomater ; 10(2): 831-42, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24516867

RESUMO

In this study, thermally responsive polymeric nanoparticle-encapsulated curcumin (nCCM) was prepared and characterized. The nCCM is ≈ 22 and 300 nm in diameter at 37 and 22 °C, respectively. The smaller size of the nCCM at 37 °C was found to significantly facilitate its uptake in vitro by human prostate adenocarcinoma PC-3 cancer cells. However, the intracellular nCCM decreases rapidly (rather than plateaus) after reaching its peak at ≈ 1.5 h during a 3-day incubation of the PC-3 cells with nCCM. Moreover, a mild hyperthermia (with negligible cytotoxicity alone) at 43 °C applied between 1 and 1.5 h during the 3-day incubation not only increases the peak uptake but also alters intracellular distribution of nCCM (facilitating its delivery into cell nuclei), which helps to retain a significantly much higher level of intracellular curcumin. These effects of mild hyperthermia could be due in part to the thermal responsiveness of the nCCM: they are more positively charged at 43 °C and can be more easily attracted to the negatively charged nuclear membrane to enter nuclei as a result of electrostatic interaction. Ultimately, a combination of the thermally responsive nCCM and mild hyperthermia significantly enhances the anticancer capability of nCCM, resulting in a more than 7-fold decrease in its inhibitory concentration to reduce cell viability to 50% (IC50). Further mechanistic studies suggest injury pathways associated with heat shock proteins 27 and 70 should contribute to the enhanced cancer cell destruction by inducing cell apoptosis and necrosis. Overall, this study demonstrates the potential of combining mild hyperthermia and thermally responsive nanodrugs such as nCCM for augmented cancer therapy.


Assuntos
Curcumina/uso terapêutico , Hipertermia Induzida , Nanopartículas/química , Neoplasias/patologia , Neoplasias/terapia , Temperatura , Linhagem Celular Tumoral , Quitosana/química , Terapia Combinada , Curcumina/química , Humanos , Espaço Intracelular/química , Espectroscopia de Ressonância Magnética , Nanopartículas/ultraestrutura , Tamanho da Partícula , Poloxâmero/química
10.
J Org Chem ; 78(20): 10166-77, 2013 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-24044416

RESUMO

Sphenostylisins A-C (1-3), three complex dimeric compounds representing two novel carbon skeletons, along with an additional eight new compounds, sphenostylisins D-K (4-11), were isolated from the active chloroform-soluble extract of the root bark of Sphenostylis marginata ssp. erecta using a bioactivity-guided isolation approach. The structures were elucidated by means of detailed spectroscopic analysis, including NMR and HRESIMS analysis, and tandem MS fragmentation was utilized to further support the structures of 1-3. The absolute configuration of sphenostylisin C (3) was established by electronic circular dichroism analysis. Plausible biogenetic relationships between the modified isoflavonoids 1-11 are proposed, and a cyclization reaction of 9 was conducted to support one of the biogenetic proposals made. All of these pure isolates were evaluated against a panel of in vitro bioassays, and among the results obtained, sphenostylisin A (1) was found to be a very potent NF-κB inhibitor (IC50 = 6 nM).


Assuntos
Isoflavonas/química , Isoflavonas/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Sphenostylis/química , Dicroísmo Circular , Espectroscopia de Ressonância Magnética , Extratos Vegetais/isolamento & purificação
11.
J Chem Inf Model ; 52(5): 1345-55, 2012 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-22540736

RESUMO

Kinase targets have been demonstrated to undergo major conformational reorganization upon ligand binding. Such protein conformational plasticity remains a significant challenge in structure-based virtual screening methodology and may be approximated by screening against an ensemble of diverse protein conformations. Maternal embryonic leucine zipper kinase (MELK), a member of serine-threonine kinase family, has been recently found to be involved in the tumerogenic state of glioblastoma, breast, ovarian, and colon cancers. We therefore modeled several conformers of MELK utilizing the available chemogenomic and crystallographic data of homologous kinases. We carried out docking pose prediction and virtual screening enrichment studies with these conformers. The performances of the ensembles were evaluated by their ability to reproduce known inhibitor bioactive conformations and to efficiently recover known active compounds early in the virtual screen when seeded with decoy sets. A few of the individual MELK conformers performed satisfactorily in reproducing the native protein-ligand pharmacophoric interactions up to 50% of the cases. By selecting an ensemble of a few representative conformational states, most of the known inhibitor binding poses could be rationalized. For example, a four conformer ensemble is able to recover 95% of the studied actives, especially with imperfect scoring function(s). The virtual screening enrichment varied considerably among different MELK conformers. Enrichment appears to improve by selection of a proper protein conformation. For example, several holo and unliganded active conformations are better to accommodate diverse chemotypes than ATP-bound conformer. These results prove that using an ensemble of diverse conformations could give a better performance. Applying this approach, we were able to screen a commercially available library of half a million compounds against three conformers to discover three novel inhibitors of MELK, one from each template. Among the three compounds validated via experimental enzyme inhibition assays, one is relatively potent (15; K(d) = 0.37 µM), one moderately active (12; K(d) = 3.2 µM), and one weak but very selective (9; K(d) = 18 µM). These novel hits may be utilized to assist in the development of small molecule therapeutic agents useful in diseases caused by deregulated MELK, and perhaps more importantly, the approach demonstrates the advantages of choosing an appropriate ensemble of a few conformers in pursuing compound potency, selectivity, and novel chemotypes over using single target conformation for structure-based drug design in general.


Assuntos
Descoberta de Drogas , Ligantes , Modelos Moleculares , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas , Simulação por Computador , Avaliação Pré-Clínica de Medicamentos , Humanos , Conformação Proteica
12.
Invest New Drugs ; 30(3): 916-26, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21340507

RESUMO

Constitutive activation of Signal Transducers and Activators of Transcription 3 (STAT3) is frequently detected in osteosarcoma, and hence, may serve as a therapeutic target. In order to target STAT3, we tested two new STAT3 inhibitors, LLL12 and FLLL32. LLL12 and FLLL32 inhibit STAT3 phosphorylation and STAT3 downstream targets. LLL12 and FLLL32 also inhibit IL-6 induced STAT3 phosphorylation. The inhibition of STAT3 by LLL12 and FLLL32 resulted in the induction of apoptosis, reduction of plating efficiency, and migration in osteosarcoma cells. Furthermore, LLL12 and FLLL32 inhibited SJSA osteosarcoma cells and OS-33 tumor growth in murine xenografts. These results provide evidence that constitutive STAT3 signaling is required for osteosarcoma survival and migration in vitro and tumor growth in vivo. Blocking persistent STAT3 signaling by LLL12 and FLLL32 may be a novel therapeutic approach for osteosarcoma.


Assuntos
Antraquinonas/uso terapêutico , Antineoplásicos/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Curcumina/análogos & derivados , Osteossarcoma/tratamento farmacológico , Fator de Transcrição STAT3/antagonistas & inibidores , Sulfonamidas/uso terapêutico , Animais , Antraquinonas/farmacologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/patologia , Linhagem Celular , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Curcumina/farmacologia , Curcumina/uso terapêutico , Feminino , Humanos , Interleucina-6/farmacologia , Camundongos , Camundongos Nus , Osteossarcoma/metabolismo , Osteossarcoma/patologia , Fosforilação/efeitos dos fármacos , Fator de Transcrição STAT3/metabolismo , Sulfonamidas/farmacologia , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
13.
BMC Cancer ; 11: 112, 2011 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-21443800

RESUMO

BACKGROUND: Curcumin is a naturally occurring phenolic compound shown to have a wide variety of antitumor activities; however, it does not attain sufficient blood levels to do so when ingested. Using structure-based design, a novel compound, FLLL32, was generated from curcumin. FLLL32 possesses superior biochemical properties and more specifically targets STAT3, a transcription factor important in tumor cell survival, proliferation, metastasis, and chemotherapy resistance. In our previous work, we found that several canine and human osteosarcoma (OSA) cell lines, but not normal osteoblasts, exhibit constitutive phosphorylation of STAT3. Compared to curcumin, we hypothesized that FLLL32 would be more efficient at inhibiting STAT3 function in OSA cells and that this would result in enhanced downregulation of STAT3 transcriptional targets and subsequent death of OSA cells. METHODS: Human and canine OSA cells were treated with vehicle, curcumin, or FLLL32 and the effects on proliferation (CyQUANT®), apoptosis (SensoLyte® Homogeneous AMC Caspase- 3/7 Assay kit, western blotting), STAT3 DNA binding (EMSA), and vascular endothelial growth factor (VEGF), survivin, and matrix metalloproteinase-2 (MMP2) expression (RT-PCR, western blotting) were measured. STAT3 expression was measured by RT-PCR, qRT- PCR, and western blotting. RESULTS: Our data showed that FLLL32 decreased STAT3 DNA binding by EMSA. FLLL32 promoted loss of cell proliferation at lower concentrations than curcumin leading to caspase-3- dependent apoptosis, as evidenced by PARP cleavage and increased caspase 3/7 activity; this could be inhibited by treatment with the pan-caspase inhibitor Z-VAD-FMK. Treatment of OSA cells with FLLL32 decreased expression of survivin, VEGF, and MMP2 at both mRNA and protein levels with concurrent decreases in phosphorylated and total STAT3; this loss of total STAT3 occurred, in part, via the ubiquitin-proteasome pathway. CONCLUSIONS: These data demonstrate that the novel curcumin analog FLLL32 has biologic activity against OSA cell lines through inhibition of STAT3 function and expression. Future work with FLLL32 will define the therapeutic potential of this compound in vivo.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias Ósseas/patologia , Curcumina/análogos & derivados , DNA/metabolismo , Osteossarcoma/patologia , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Animais , Apoptose/genética , Neoplasias Ósseas/genética , Linhagem Celular Tumoral , Curcumina/farmacologia , Doenças do Cão/genética , Doenças do Cão/patologia , Cães , Avaliação Pré-Clínica de Medicamentos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Osteossarcoma/genética , Ligação Proteica/efeitos dos fármacos
14.
J Cardiovasc Pharmacol ; 54(5): 412-20, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19730393

RESUMO

Genistein is a phytoestrogen that is known to have a protective effect on the vascular endothelial wall. However, it exhibits poor bioavailability, which limits the use of genistein to treat cardiovascular and cerebrovascular diseases. A novel genistein derivative, 7-difluoromethyl-5,4'-dimethoxygenistein (dFMGEN), has shown a better protective effect on vascular endothelial damage in vitro than genistein. In this study, we further evaluated therapeutic effects of dFMGEN on the vascular endothelial wall and atherosclerosis in a rabbit model in vivo. There were 5 groups: the GEN group (genistein 5 mg/kg per day), lovastatin group (lovastatin 5 mg/kg per day), dFMGEN group (dFMGEN 5 mg/kg per day), model control group (the same amount of vehicle solvent), and the normal control group; all feedings administered via intragastric administration. We demonstrated that dFMGEN (1) attenuated the development of atherosclerosis, (2) reduced serum total cholesterol and low-density lipoprotein cholesterol concentrations, (3) decreased lipid peroxidation in the rabbit atherosclerosis model, and (4) increased smooth muscle cell and collagen content in atheroma of thoracic aortas. These results provide an experimental foundation for dFMGEN's potential effects in preventing and treating atherosclerosis, acute coronary syndromes, and potentially ischemia-reperfusion injury during acute myocardial infarction and cerebral infarction.


Assuntos
Aterosclerose/tratamento farmacológico , Endotélio Vascular/efeitos dos fármacos , Genisteína/análogos & derivados , Fitoestrógenos/uso terapêutico , Animais , Aorta Abdominal/efeitos dos fármacos , Aorta Abdominal/metabolismo , Aorta Abdominal/patologia , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/metabolismo , Aorta Torácica/patologia , Aterosclerose/sangue , Aterosclerose/metabolismo , Aterosclerose/patologia , Colesterol/sangue , Colágeno/metabolismo , Modelos Animais de Doenças , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Genisteína/administração & dosagem , Genisteína/uso terapêutico , Peroxidação de Lipídeos/efeitos dos fármacos , Lipoproteínas LDL/sangue , Masculino , Fitoestrógenos/administração & dosagem , Coelhos
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