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1.
NPJ Precis Oncol ; 7(1): 93, 2023 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-37717087

RESUMO

As a highly lethal adenocarcinoma of the hepatobiliary system, outcomes for cholangiocarcinoma (CCA) patients remain prominently poor with a 5-year survival of <10% due to the lack of effective treatment modalities. Targeted therapeutics for CCA are limited and surgical resection of CCA frequently suffers from a high recurrence rate. Here we report two effective targeted therapeutics in this preclinical study for CCA. We first performed a quantitative and unbiased screening of cancer-related antigens using comparative flow cytometry in a panel of human CCA cell lines, and identified intercellular adhesion molecule-1 (ICAM1) as a therapeutic target for CCA. After determining that ICAM1 has the ability to efficiently mediate antibody internalization, we constructed two ICAM1 antibody-drug conjugates (ADCs) by conjugating ICAM1 antibodies to different cytotoxic payloads through cleavable chemical linkers. The efficacies of two ICAM1 ADCs have been evaluated in comparison with the first-line chemodrug Gemcitabine in vitro and in vivo, and ICAM1 antibodies coupled with warhead DX-8951 derivative (DXd) or monomethyl auristatin E (MMAE) elicit a potent and consistent tumor attenuation. In summary, this study paves the road for developing a promising targeted therapeutic candidate for clinical treatment of CCA.

2.
iScience ; 26(8): 107272, 2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37520726

RESUMO

Treatment options for anaplastic thyroid cancer (ATC) and refractory papillary thyroid carcinoma (PTC) are limited and outcomes remain poor. In this study, we determined via bioinformatic expression analyses and immunohistochemistry staining that intercellular adhesion molecule-1(ICAM1) is an attractive target for ATC and PTC. We designed and engineered two ICAM1-directed antibody-drug conjugate (I1-MMAE and I1-DXd), both of which potently and selectively ablate multiple human ATC and PTC cell lines without affecting non-plastic cells in vitro. Furthermore, I1-MMAE and I1-DXd mediated a potent tumor regression in ATC and PTC xenograft models. To develop a precision medicine, we also explored magnetic resonance imaging (MRI) as a non-invasive biomarker detection method to quantitatively map ICAM1 antigen expression in heterogeneous thyroid tumors. Taken together, this study provides a strong rationale for the further development of I1-MMAE and I1-DXd as promising therapeutic candidates to treat advanced PTC and ATC.

3.
Sci Adv ; 9(18): eabq7866, 2023 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-37146146

RESUMO

Triple-negative breast cancer (TNBC) remains the most lethal form of breast cancer, and effective targeted therapeutics are in urgent need to improve the poor prognosis of TNBC patients. Here, we report the development of a rationally designed antibody drug conjugate (ADC) for the treatment of late-stage and refractory TNBC. We determined that intercellular adhesion molecule-1 (ICAM1), a cell surface receptor overexpressed in TNBC, efficiently facilitates receptor-mediated antibody internalization. We next constructed a panel of four ICAM1 ADCs using different chemical linkers and warheads and compared their in vitro and in vivo efficacies against multiple human TNBC cell lines and a series of standard, late-stage, and refractory TNBC in vivo models. An ICAM1 antibody conjugated with monomethyl auristatin E (MMAE) via a protease-cleavable valine-citrulline linker was identified as the optimal ADC formulation owing to its outstanding efficacy and safety, representing an effective ADC candidate for TNBC therapy.


Assuntos
Imunoconjugados , Neoplasias de Mama Triplo Negativas , Humanos , Imunoconjugados/farmacologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Molécula 1 de Adesão Intercelular , Ensaios Antitumorais Modelo de Xenoenxerto , Linhagem Celular Tumoral
4.
Brain Topogr ; 35(4): 375-397, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35666364

RESUMO

This study empirically assessed the strength and duration of short-term effects induced by brain reactions to closing/opening the eyes on a few well-known resting-state networks. We also examined the association between these reactions and subjects' cortisol levels. A total of 55 young adults underwent 8-min resting-state fMRI (rs-fMRI) scans under 4-min eyes-closed and 4-min eyes-open conditions. Saliva samples were collected from 25 of the 55 subjects before and after the fMRI sessions and assayed for cortisol levels. Our empirical results indicate that when the subjects were relaxed with their eyes closed, the effect of opening the eyes on conventional resting-state networks (e.g., default-mode, frontal-parietal, and saliency networks) lasted for roughly 60-s, during which we observed a short-term increase in activity in rs-fMRI time courses. Moreover, brain reactions to opening the eyes had a pronounced effect on time courses in the temporo-parietal lobes and limbic structures, both of which presented a prolonged decrease in activity. After controlling for demographic factors, we observed a significantly positive correlation between pre-scan cortisol levels and connectivity in the limbic structures under both conditions. Under the eyes-closed condition, the temporo-parietal lobes presented significant connectivity to limbic structures and a significantly positive correlation with pre-scan cortisol levels. Future research on rs-fMRI could consider the eyes-closed condition when probing resting-state connectivity and its neuroendocrine correlates, such as cortisol levels. It also appears that abrupt instructions to open the eyes while the subject is resting quietly with eyes closed could be used to probe brain reactivity to aversive stimuli in the ventral hippocampus and other limbic structures.


Assuntos
Mapeamento Encefálico , Hidrocortisona , Encéfalo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética/métodos , Descanso , Adulto Jovem
5.
PeerJ ; 10: e13142, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35341053

RESUMO

Background: In North America, up to one billion birds are estimated to die annually due to collisions with glass. The transparent and reflective properties of glass present the illusion of a clear flight passage or continuous habitat. Approaches to reducing collision risk involve installing visual cues on glass that enable birds to perceive glass as a solid hazard at a sufficient distance to avoid it. Methods: We monitored for bird-window collisions between 2013 and 2018 to measure response to bird protection window treatments at two low-rise buildings at the Alaksen National Wildlife Area in Delta, British Columbia, Canada. After 2 years of collision monitoring in an untreated state, we retrofitted one building with Feather Friendly® circular adhesive markers applied in a grid pattern across all windows, enabling a field-based assessment of the relative reduction in collisions in the 2 years of monitoring following treatment. An adjacent building that had been constructed with a bird protective UV-treated glass called ORNILUX® Mikado, was monitored throughout the two study periods. Carcass persistence trials were conducted to evaluate the likelihood that carcasses were missed due to carcass removal between scheduled searches. Results and Conclusions: After accounting for differences in area of glass between the two buildings, year, and observer effects, our best-fit model for explaining collision risk included the building's treatment group, when compared to models that included building and season only. We found that the Feather Friendly® markers reduced collision risk at the retrofitted building by 95%. Collision incidence was also lower at the two monitored façades of the building with ORNILUX® glass compared to the building with untreated glass. Although more research is needed on the effectiveness of bird-protection products across a range of conditions, our results highlight the benefit of these products for reducing avian mortality due to collisions with glass.


Assuntos
Animais Selvagens , Ecossistema , Animais , Aves/fisiologia , Vidro , Colúmbia Britânica
6.
Antib Ther ; 5(1): 18-29, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35146330

RESUMO

Antibody-drug conjugates (ADCs) combining potent cytotoxicity of small-molecule drugs with the selectivity and excellent pharmacokinetic profile of monoclonal antibody (mAb) are promising therapeutic modalities for a diverse range of cancers. Owing to overexpression in a wide range of tumors, human epidermal growth factor receptor 2 (Her2) is one of the most utilized targeting antigens for ADCs to treat Her2-positive cancers. Owing to the high density of Her2 antigens on the tumor cells and high affinity and high internalization capacity of corresponding antibodies, 56 anti-Her2 ADCs which applied >10 different types of novel payloads had entered preclinical or clinical trials. Seven of 12 Food and Drug Administration (FDA)-approved ADCs including Polivy (2019), Padcev (2019), EnHertu (2019), Trodelvy (2020), Blenrep (2020), Zynlonta (2021), and Tivdak) (2021) have been approved by FDA in the past three years alone, indicating that the maturing of ADC technology brings more productive clinical outcomes. This review, focusing on the anti-Her2 ADCs in clinical trials or on the market, discusses the strategies to select antibody formats, the linkages between linker and mAb, and effective payloads with particular release and action mechanisms for a good clinical outcome.

7.
J Am Chem Soc ; 143(17): 6691-6700, 2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33876925

RESUMO

Diazirines are widely used in photoaffinity labeling (PAL) to trap noncovalent interactions with biomolecules. However, design and interpretation of PAL experiments is challenging without a molecular understanding of the reactivity of diazirines with protein biomolecules. Herein, we report a systematic evaluation of the labeling preferences of alkyl and aryl diazirines with individual amino acids, single proteins, and in the whole cell proteome. We find that alkyl diazirines exhibit preferential labeling of acidic amino acids in a pH-dependent manner that is characteristic of a reactive alkyl diazo intermediate, while the aryl-fluorodiazirine labeling pattern reflects reaction primarily through a carbene intermediate. From a survey of 32 alkyl diazirine probes, we use this reactivity profile to rationalize why alkyl diazirine probes preferentially enrich highly acidic proteins or those embedded in membranes and why probes with a net positive charge tend to produce higher labeling yields in cells and in vitro. These results indicate that alkyl diazirines are an especially effective chemistry for surveying the membrane proteome and will facilitate design and interpretation of biomolecular labeling experiments with diazirines.


Assuntos
Compostos de Diazônio/química , Marcadores de Fotoafinidade/química , Proteínas/química , Aminoácidos/análise , Aminoácidos/química , Sítios de Ligação , Diazometano/química , Humanos , Concentração de Íons de Hidrogênio , Conformação Proteica , Proteínas/análise , Proteoma/análise , Proteoma/química , Canal de Ânion 1 Dependente de Voltagem/química
8.
Environ Pollut ; 238: 306-316, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29573713

RESUMO

Productive coastal and estuarine habitats can be degraded by contaminants including persistent organic pollutants (POPs) such as PCBs, dioxins, and organochlorine insecticides to the extent of official designation as contaminated sites. Top-predatory wildlife may continue to use such sites as the habitat often appears suitable, and thus bioaccumulate POPs and other contaminants with potential consequences on their health and fitness. Victoria and Esquimalt harbours are located on southern Vancouver Island, British Columbia (BC) and are federally designated contaminated sites due mainly to past heavy industrial activities, such as from shipyards and sawmills. We collected scat samples from river otters (Lontra canadensis) throughout an annual cycle, and combined chemical analysis with DNA genotyping to examine whether the harbour areas constituted a contaminant-induced ecological trap for otters. We confirmed spatial habitat use by radio telemetry of a subsample of otters. Fifteen percent of otter scat contained PCB concentrations exceeding levels considered to have adverse effects on the reproduction of mink (Neovison vison), and there were significant positive correlations between concentrations of PCBs and of thyroid (T3) and sex (progesterone) hormones in fecal samples. Radio telemetry data revealed that otters did not show directional movement away from the harbours, indicating their inability to recognize the contaminated site as a degraded habitat. However, analysis and modeling of the DNA genotyping data provided no evidence that the harbour otters formed a sink population and therefore were in an ecological trap. Despite the highly POP-contaminated habitat, river otters did not appear to be adversely impacted at the population level. Our study demonstrates the value of combining chemical and biological technologies with ecological theory to investigate practical conservation problems.


Assuntos
Monitoramento Ambiental , Lontras/fisiologia , Poluentes Químicos da Água/metabolismo , Animais , Colúmbia Britânica , Demografia , Fezes/química , Hidrocarbonetos Clorados/análise , Hidrocarbonetos Clorados/metabolismo , Inseticidas/análise , Inseticidas/metabolismo , Masculino , Vison , Lontras/metabolismo , Bifenilos Policlorados/análise , Bifenilos Policlorados/metabolismo , Reprodução/efeitos dos fármacos , Rios , Poluentes Químicos da Água/análise
9.
Mol Cell Proteomics ; 17(4): 764-775, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29351928

RESUMO

Post-translational modifications (PTMs) on proteins often function to regulate signaling cascades, with the activation of T cells during an adaptive immune response being a classic example. Mounting evidence indicates that the modification of proteins by O-linked N-acetylglucosamine (O-GlcNAc), the only mammalian glycan found on nuclear and cytoplasmic proteins, helps regulate T cell activation. Yet, a mechanistic understanding of how O-GlcNAc functions in T cell activation remains elusive, partly because of the difficulties in mapping and quantifying O-GlcNAc sites. Thus, to advance insight into the role of O-GlcNAc in T cell activation, we performed glycosite mapping studies via direct glycopeptide measurement on resting and activated primary human T cells with a technique termed Isotope Targeted Glycoproteomics. This approach led to the identification of 2219 intact O-linked glycopeptides across 1045 glycoproteins. A significant proportion (>45%) of the identified O-GlcNAc sites lie near or coincide with a known phosphorylation site, supporting the potential for PTM crosstalk. Consistent with other studies, we find that O-GlcNAc sites in T cells lack a strict consensus sequence. To validate our results, we employed gel shift assays based on conjugating mass tags to O-GlcNAc groups. Notably, we observed that the transcription factors c-JUN and JUNB show higher levels of O-GlcNAc glycosylation and higher levels of expression in activated T cells. Overall, our findings provide a quantitative characterization of O-GlcNAc glycoproteins and their corresponding modification sites in primary human T cells, which will facilitate mechanistic studies into the function of O-GlcNAc in T cell activation.


Assuntos
Acetilglucosamina/metabolismo , Glicopeptídeos/metabolismo , Linfócitos T/metabolismo , Células Cultivadas , Deutério , Humanos , Ativação Linfocitária , Processamento de Proteína Pós-Traducional , Proteômica , Proteínas Proto-Oncogênicas c-jun/metabolismo
10.
BMC Ecol ; 17(1): 29, 2017 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-28797249

RESUMO

BACKGROUND: Long-distance migratory birds in North America have undergone precipitous declines over the past half-century. Although the trend is clear, for many migrating species underpinning the exact causes poses a challenge to conservation due to the numerous stressors that they encounter. Climate conditions during all phases of their annual cycle can have important consequences for their survival. Here, using 15 years of capture-recapture dataset, we determined the effects of various climate factors during the breeding, wintering, and migrating stages on the annual survival of a western yellow-breasted chat (Icteria virens auricollis) population breeding in southwestern Canada. RESULTS: El Niño effects over the entire annual cycle had little influence on the annual apparent survival of yellow-breasted chats. However, we found evidence that wind conditions during migration, specifically average westerly wind speed or the frequency of storm events, had significant adverse effects on adult annual apparent survival. In comparison, precipitation levels on wintering ground had little to no influence on adult annual apparent survival, whereas growing degree days on the breeding ground had moderate but positive effects. CONCLUSIONS: In the face of climate change and its predicted impacts on climate processes, understanding the influence of weather conditions on the survival of migrating birds can allow appropriate conservation strategies to be adopted for chats and other declining neotropical migrants.


Assuntos
Passeriformes/fisiologia , Migração Animal , Animais , Cruzamento , Mudança Climática , Ecossistema , Feminino , Masculino , Estações do Ano
11.
Ecotoxicology ; 25(6): 1061-71, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27151403

RESUMO

Among many anthropogenic drivers of population decline, continual rapid urbanization and industrialization pose major challenges for the survival of wildlife species. Barn owls (Tyto alba) in southwestern British Columbia (BC) face a multitude of threats ranging from habitat fragmentation to vehicle strikes. They are also at risk from secondary poisoning of second-generation anticoagulant rodenticides (SGARs), a suite of toxic compounds which at high doses results in a depletion of blood clotting factors leading to internal bleeding and death. Here, using long-term data (N = 119) for the hepatic residue levels of SGAR, we assessed the risk of toxicosis from SGAR for the BC barn owl population over the past two decades. We also investigated whether sensitivity to SGAR is associated with genetic factors, namely Single Nucleotide Polymorphisms (SNPs) found in the CYP2C45 gene of barn owls. We found that residue concentration for total SGAR was significantly higher in 2006-2013 (141 ng/g) relative to 1992-2003 (57 ng/g). The proportion of owls exposed to multiple SGAR types was also significantly higher in 2006-2013. Those measures accordingly translate directly into an increase in toxicosis risk level. We also detected demographic differences, where adult females showed on average lower concentration of total SGAR (64 ng/g) when compared to adult males (106 ng/g). Juveniles were overall more likely to show signs of toxicosis than adults (33.3 and 6.9 %, respectively), and those symptoms were positively predicted by SGAR concentrations. We found no evidence that SNPs in the CYP2C45 gene of barn owls were associated with intraspecific variation in SGAR sensitivity. We recommend several preventative measures be taken to minimize wildlife exposure to SGAR.


Assuntos
Anticoagulantes/toxicidade , Monitoramento Ambiental , Rodenticidas/toxicidade , Estrigiformes/fisiologia , Animais , Colúmbia Britânica , Relação Dose-Resposta a Droga , Poluentes Ambientais/toxicidade , Risco
12.
Chin J Integr Med ; 21(2): 123-31, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25081895

RESUMO

OBJECTIVE: To study the effect of Tiantai No. 1 [symbol in text] on gene expression profile in hippocampus of Alzheimer's disease (AD) rat, molecular genetic target points of the effect of this drug were defined, its molecular genetic pharmacodynamic mechanism of anti-AD was further explored at molecular gene level, and a scientific basis was provided for its clinical availability and promotion. METHODS: Thirty male Sprague-Dawley rats were divided into three groups with 10 rats per group: sham-operation group, model group and Tiantai No. 1 group. Sterile surgical procedure was applied, the model group with bilateral hippocampal injection of Aß1-40 was established, and normal saline was used instead of Aß1-40 in the sham-operation group. One week after the models was made, rats were administered by gastric lavage once every day for three consecutive weeks. The rats of the sham-operation group and the model group were daily fed with purified water by lavage; the rats of the Tiantai No.1 group treated group were administered with Tiantai No.1 by lavage. Total RNAs of hippocampus tissues were extracted with Trizol, the changes of hippocampus gene expression profiles in the above three groups were analyzed by using Affymetrix rat whole genome expression profile microarray. RESULTS: Microarray analysis showed that, compared with the sham-operation group, the hippocampus of the model group had 50 up-regulated genes with significant difference (fold change >2), and 21 down-regulated genes with significant difference (fold change <0.5); compared with the hippocampus of the model group, the hippocampus of the Tiantai No. 1 group was found to have 5 up-regulated genes with significant difference (fold change >2) and 20 down-regulated genes with significant difference (fold change <0.5). The functions of differentially expressed genes of the groups were involved in nervous system's development, neuronic differentiation and function-regulation, cellular growth and differentiation and apoptosis, synaptic occurrence and plasticity, inflammation and immune response, ion channels/transporters, cellular signal transduction, cellular material/energy metabolism and so on. CONCLUSION: Tiantai No. 1 can regulate hippocampal function, and further regulate the brain function of animals in multiple gene target points by a number of ways.


Assuntos
Doença de Alzheimer/genética , Biologia Computacional/métodos , Medicamentos de Ervas Chinesas/farmacologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Doença de Alzheimer/patologia , Animais , Peso Corporal/efeitos dos fármacos , Eletroforese em Gel de Ágar , Hipocampo/patologia , Masculino , Desnaturação de Ácido Nucleico , Tamanho do Órgão/efeitos dos fármacos , RNA/isolamento & purificação , RNA/metabolismo , Ratos Sprague-Dawley
13.
Neural Regen Res ; 7(3): 165-70, 2012 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-25767493

RESUMO

A rat model of Parkinson's disease was induced by injecting lactacystin stereotaxically into the left mesencephalic ventral tegmental area and substantia nigra pars compacta. After rats were intragastrically perfused with Anchanling, a Chinese medicine, mainly composed of magnolol, for 5 weeks, when compared with Parkinson's disease model rats, tyrosine hydroxylase expression was increased, α-synuclein and ubiquitin expression was decreased, substantia nigra cell apoptosis was reduced, and apomorphine-induced rotational behavior was improved. Results suggested that Anchanling can ameliorate Parkinson's disease pathology possibly by enhancing degradation activity of the ubiquitin-proteasome system.

14.
Chin J Integr Med ; 16(1): 41-9, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20131035

RESUMO

OBJECTIVE: Changes of the internal and external cellular environments can induce calcium homeostasis disorder and unfolded protein aggregation in the endoplasmic reticulum (ER). This ER function disorder is called endoplasmic reticulum stress (ERS). Severe long-term ERS can trigger the ER apoptosis signaling pathway, resulting in cell apoptosis and organism injury. Recent researches revealed that ERS-induced cell death was involved in the neurocyte retrogradation in the progress of neuron degenerative diseases, such as Alzheimer's disease (AD), Parkinson's disease and so on. Therefore, the protection effect of the traditional Chinese drug-Tiantai No. 1 (1) on the ERS injury of AD was investigated at the molecular gene level in this study with a view to explore the gene pharmacodynamic actions and mechanisms of this drug. METHODS: Primarily cultured marrow mesenchymal stem cells (MSCs) of rats were treated by tunicamycin (TM) in order to induce ERS. RT-PCR, fluorescence immunocytochemistry and Western blot techniques were used to determine the mRNA and protein expression levels of the protective stress protein-ER molecular chaperones GRP78 and GRP94 (which would assist cells to resist cellular stress injury), and to determine the mRNA and protein expression levels of apoptosis promoting molecule Caspase-12 on the membrane of the ER, respectively. RESULTS: Protein expression levels of GRP78 and GRP94 were significantly increased in the TM-induced MSCs, and the mRNA level of Caspase-12 was also remarkably increased in the TM-induced MSCs (P<0.05). All these proved that the ERS model was successfully established by TM in MSC. Meanwhile, the mRNA and protein levels of GRP78 and GRP94 were all significantly increased compared with the model group (P<0.05 or P<0.01) after MSCs were treated with Tiantai No.1 while the mRNA and protein expression levels of Caspase-12 were significantly decreased compared with the model group (P<0.05 or P<0.01). This effect showed a dose dependent manner. CONCLUSION: Tiantai No.1 might attenuate the cell apoptosis induced by ERS injury, and thus protect the neurons against AD.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Retículo Endoplasmático/efeitos dos fármacos , Células-Tronco Mesenquimais/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Tunicamicina/antagonistas & inibidores , Tunicamicina/farmacologia , Animais , Antibacterianos/antagonistas & inibidores , Antibacterianos/farmacologia , Células Cultivadas , Antagonismo de Drogas , Retículo Endoplasmático/metabolismo , Chaperona BiP do Retículo Endoplasmático , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Masculino , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Células-Tronco Mesenquimais/metabolismo , RNA/análise , RNA/efeitos dos fármacos , Coelhos , Ratos , Ratos Sprague-Dawley , Estresse Fisiológico/genética
15.
Chin J Integr Med ; 14(4): 286-92, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19082801

RESUMO

OBJECTIVE: To investigate the effect and molecular mechanism of Tiantai No.1, a compound Chinese herbal preparation, for the prevention and reduction of neurotoxicity induced by beta-amyloid peptides (Abeta) in vitro and its effects on nuclear factor-kappa B (NF-kappa B) and cAMP responsive element-binding protein (CREB) pathways using the gene transfection technique. METHODS: B104 neuronal cells were used to examine the effects of Tiantai No.1 on lowering the neurotoxicity induced by Abeta. The cells were pre-treated with Tiantai No.1 at doses of 50, 100, 150, or 200 micro g/mL respectively for 3 days and co-treated with Tiantai No.1 and beta-amyloid peptide1-40 (A beta 1-40, 10 micro mol/L) for 48 h or post-treated with Tiantai No.1 for 48 h after the cells were exposed to beta-amyloid peptides25-35 (A beta 25-35) for 8 h. In gene transfection assays, cells were treated with Tiantai No.1 at 50 micro g/mL and 150 micro g/mL for 5 days or co-treated with Tiantai No.1 and A beta 1-40 (5 micro mo/L) for 3 days after electroporation for the evaluation of NF-kappa B and CREB expression. RESULTS: Pre-treating and co-treating B104 neuronal cells with Tiantai No.1 lowered the neurotoxicity induced by Abeta, and post-treating with Tiantai No.1 reduced or blocked B104 neuronal apoptotic death induced by Abeta (P<0.05, P<0.01). With a dose-dependent relationship, the same treatments increased the expression of NF-kappa B or CREB in B104 neuronal cells (P<0.05, P<0.01). Meanwhile, Tiantai No.1 reduced A beta -40 induced inhibition on NF-kappa B expression (P<0.01). CONCLUSIONS: Tiantai No.1 can protect neurons against the neurotoxicity induced by Abeta. The neuroprotective mechanisms may be associated with the activation of NF-kappa B and cAMP cellular signal pathways.


Assuntos
Peptídeos beta-Amiloides , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/análise , Medicamentos de Ervas Chinesas/farmacologia , NF-kappa B/análise , Neurônios/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Células Cultivadas , Eletroporação , Luciferases , Microscopia de Fluorescência , Ratos , Transfecção
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