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BACKGROUND: The centrosome is one of the most important non-membranous organelles regulating microtubule organization and progression of cell mitosis. The coiled-coil alpha-helical rod protein 1 (CCHCR1, also known as HCR) gene is considered to be a psoriasis susceptibility gene, and the protein is suggested to be localized to the P-bodies and centrosomes in mammalian cells. However, the exact cellular function of HCR and its potential regulatory role in the centrosomes remain unexplored. RESULTS: We found that HCR interacts directly with astrin, a key factor in centrosome maturation and mitosis. Immunoprecipitation assays showed that the coiled-coil region present in the C-terminus of HCR and astrin respectively mediated the interaction between them. Astrin not only recruits HCR to the centrosome, but also protects HCR from ubiquitin-proteasome-mediated degradation. In addition, depletion of either HCR or astrin significantly reduced centrosome localization of CEP72 and subsequent MCPH proteins, including CEP152, CDK5RAP2, and CEP63. The absence of HCR also caused centriole duplication defects and mitotic errors, resulting in multipolar spindle formation, genomic instability, and DNA damage. CONCLUSION: We conclude that HCR is localized and stabilized at the centrosome by directly binding to astrin. HCR are required for the centrosomal recruitment of MCPH proteins and centriolar duplication. Both HCR and astrin play key roles in keeping normal microtubule assembly and maintaining genomic stability.
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Proteínas de Ciclo Celular , Centríolos , Animais , Centríolos/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Centrossomo/metabolismo , Mitose , Ubiquitinas/genética , Fuso Acromático/metabolismo , MamíferosRESUMO
Trichosanthin (TCS) is a type I ribosome-inactivating protein extracted from the tuberous root of the plant Trichosanthes. TCS shows promising potential in clinical drug abortion, anti-tumor and immunological regulation. However, the molecular mechanisms of its anti-tumor and immune regulation properties are still not well discovered. In the present study, we investigated the anti-tumor activity of TCS in hepatocellular carcinoma (HCC), both in vitro and in vivo. Both HCC cell lines and xenograft tumor tissues showed considerable growth inhibition after they were treated with TCS. TCS provoked caspase-mediated apoptosis in HCC cells and xenograft tumor tissues. The recruitment of CD8+ T cells to HCC tissues and the expression of chemokines, CCL2 and CCL22, were promoted upon TCS treatment. In addition, TCS induced an upregulation of Granzyme B (GrzB), TNF-α and IFN-γ in HCC tissues, which are the major cytotoxic mediators produced by T cells. Furthermore, TCS also resulted in an increase of mannose-6-phosphate receptor (M6PR), the major receptor of GrzB, in HCC tissues. In summary, these results suggest that TCS perhaps increases T-cell immunity via promoting the secretion of chemokines and accelerating the entry of GrzB to HCC cells, which highlights the potential role of TCS in anti-tumor immunotherapy.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Tricosantina , Humanos , Tricosantina/farmacologia , Tricosantina/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Linfócitos T CD8-Positivos/metabolismo , Granzimas , Neoplasias Hepáticas/tratamento farmacológico , Quimiocinas/farmacologiaRESUMO
We report herein a novel mechanism, unraveled by proteomics and validated by in vitro and in vivo studies, of the aberrant aging-associated upregulation of ovarian transferrin and ferritin in rat ovaries. The ovarian mass and serum estradiol titer plummeted while the ovarian labile ferrous iron and total iron levels escalated with age in rats. Oxidative stress markers, such as nitrite/nitrate, 3-nitrotyrosine, and 4-hydroxy-2-nonenal, accumulated in the aging ovaries due to an aberrant upregulation of the ovarian transferrin, ferritin light/heavy chains, and iron regulatory protein 2(IRP2)-mediated transferrin receptor 1 (TfR1). Ferritin inhibited estradiol biosynthesis in ovarian granulosa cells in vitro via the upregulation of a nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and p65/p50-induced oxidative and inflammatory factor inducible nitric oxide synthase (iNOS). An in vivo study demonstrated how the age-associated activation of NF-κB induced the upregulation of iNOS and the tumor necrosis factor α (TNFα). The downregulation of the keap1-mediated nuclear factor erythroid 2-related factor 2 (Nrf2), that induced a decrease in glutathione peroxidase 4 (GPX4), was observed. The aberrant transferrin and ferritin upregulation triggered an iron accumulation via the upregulation of an IRP2-induced TfR1. This culminates in NF-κB-iNOS-mediated ovarian oxi-inflamm-aging and serum estradiol decrement in naturally aging rats. The iron accumulation and the effect on ferroptosis-related proteins including the GPX4, TfR1, Nrf2, Keap1, and ferritin heavy chain, as in testicular ferroptosis, indicated the triggering of ferroptosis. In young rats, an intraovarian injection of an adenovirus, which expressed iron regulatory proteins, upregulated the ovarian NF-κB/iNOS and downregulated the GPX4. These novel findings have contributed to a prompt translational research on the ovarian aging-associated iron metabolism and aging-associated ovarian diseases.
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Ferroptose , NF-kappa B , Ratos , Animais , Feminino , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Ferritinas/metabolismo , Regulação para Cima , Nitritos/metabolismo , Transferrina/metabolismo , Estradiol/metabolismo , Nitratos/metabolismo , Ovário/metabolismo , Apoferritinas/metabolismo , Proteína 2 Reguladora do Ferro/metabolismo , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Envelhecimento , Estresse Oxidativo , Ferro/metabolismo , Receptores da Transferrina/metabolismoRESUMO
Polyphyllin II (PPII) is a natural steroidal saponin occurring in Rhizoma Paridis. It has been demonstrated to exhibit anti-cancer activity against a variety of cancer cells. However, the anti-colorectal cancer (CRC) effects and mechanism of action of PPII are rarely reported. In the present study, we showed that PPII inhibited the proliferation of HCT116 and SW620 cells. Moreover, PPII induced G2/M-phase cell cycle arrest and apoptosis, as well as protective autophagy, in CRC cells. We found that PPII-induced autophagy was associated with the inhibition of PI3K/AKT/mTOR signaling. Western blotting results further revealed that PPII lowered the protein levels of phospho-Src (Tyr416), phospho-JAK2 (Tyr1007/1008), phospho-STAT3 (Tyr705), and STAT3-targeted molecules in CRC cells. The overactivation of STAT3 attenuated the cytotoxicity of PPII against HCT116 cells, indicating the involvement of STAT3 inhibition in the anti-CRC effects of PPII. PPII (0.5 mg/kg or 1 mg/kg, i.p. once every 3 days) suppressed HCT116 tumor growth in nude mice. In alignment with the in vitro results, PPII inhibited proliferation, induced apoptosis, and lowered the protein levels of phospho-STAT3, phospho-AKT, and phospho-mTOR in xenografts. These data suggest that PPII could be a potent therapeutic agent for the treatment of CRC.
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Neoplasias Colorretais , Saponinas , Animais , Apoptose , Autofagia , Neoplasias Colorretais/patologia , Humanos , Camundongos , Camundongos Nus , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator de Transcrição STAT3/metabolismo , Saponinas/farmacologia , Saponinas/uso terapêutico , Esteroides , Serina-Treonina Quinases TOR/metabolismoRESUMO
Radix Rehmanniae, Fructus Schisandrae, Radix Bupleuri, and Fructus Gardeniae are often used alongside with clozapine (CLZ) for schizophrenia patients in order to reduce side effects and enhance therapeutic efficacy. However, worse outcomes were observed raising concern about a critical issue, herb-drug interactions, which were rarely reported when antipsychotics were included. This study aims to determine whether the concomitant use of these herbal medicines affects the pharmacokinetic characteristics of CLZ in rat models. Rats were given a single or multiple intraperitoneal injections of 10 mg/kg CLZ, either alone or with individual herbal water extracts administered orally. CLZ and its two inactive metabolites, norclozapine and clozapine N-oxide, were determined by high-performance liquid chromatography/tandem mass spectrometry. In the acute treatment, the formation of both metabolites was reduced, while no significant change was observed in the CLZ pharmacokinetics for any of the herbal extracts. In the chronic treatment, none of the four herbal extracts significantly influenced the pharmacokinetic parameters of CLZ and its metabolites. Renal and liver functions stayed normal after the 11-day combined use of herbal medicines. Overall, the four herbs had limited interaction effect on CLZ pharmacokinetics in the acute and chronic treatment. Herb-drug interaction includes both pharmacokinetic and pharmacodynamic mechanisms. This result gives us a hint that pharmacodynamic herb-drug interaction, instead of pharmacokinetic types, may exist and need further confirmation.
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Clozapina/farmacocinética , Medicamentos de Ervas Chinesas/administração & dosagem , Animais , Clozapina/administração & dosagem , Clozapina/efeitos adversos , Interações Medicamentosas , Quimioterapia Combinada , Interações Ervas-Drogas , Testes de Função Renal , Testes de Função Hepática , Masculino , Ratos , Esquizofrenia/tratamento farmacológico , Distribuição TecidualRESUMO
Dendrobium officinale is an herbal medicine that has been clinically used to promote body fluid production. Previous works demonstrated that D. officinale polysaccharides could ameliorate symptoms of salivary secretion of patients with Sjögren's syndrome and in a respective mice model. In the present study, we investigated the underlying mechanism by which D. officinale polysaccharides activate M3 muscarinic receptors and induce extracellular calcium influx, leading to the translocation of aquaporin 5, a water channel protein, to the apical membrane of human submandibular gland epithelial cells. Enzymatic treatment of D. officinale polysaccharides suggested that they are hydrolyzed but do not permeate cell membranes. This finding supports the pharmacological activity of D. officinale polysaccharides to promote salivary secretion.
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Aquaporina 5/metabolismo , Dendrobium/química , Extratos Vegetais/farmacologia , Polissacarídeos/farmacologia , Receptor Muscarínico M3/metabolismo , Síndrome de Sjogren/tratamento farmacológico , Animais , Modelos Animais de Doenças , Humanos , Camundongos , Transporte Proteico/efeitos dos fármacos , Receptor Muscarínico M3/efeitos dos fármacosRESUMO
Small pinto bean is a cultivar of Phaseolus vulgaris. It produces a 16-kDa trypsin inhibitor that could be purified using anion exchange and size chromatography. Q-Sepharose, Mono Q and Superdex 75 columns were employed for the isolation process. Small pinto bean trypsin inhibitor demonstrated moderate pH stability (pH 2-10) and marked heat stability, with its trypsin inhibitory activity largely retained after exposure to 100 °C for half an hour. The activity was abolished in the presence of dithiothreitol, in a dose-dependent manner, implying that disulfide bonds in small pinto bean trypsin inhibitor are crucial for the activity. The trypsin inhibitor showed a blocked N-terminus. The trypsin inhibitor only slightly inhibited the viability of breast cancer MCF7 and hepatoma HepG2 cells at 125 µM.
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Phaseolus/química , Sementes/química , Temperatura , Inibidores da Tripsina/farmacologia , Tripsina/metabolismo , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células Hep G2 , Humanos , Células MCF-7 , Relação Estrutura-Atividade , Inibidores da Tripsina/química , Inibidores da Tripsina/isolamento & purificaçãoRESUMO
Colorectal cancer (CRC) is the second deadliest cancer worldwide. The impact of fine particulate matter (PM2.5) on many diseases is a global concern, yet its association with CRC is unclear. This study aimed to assess the effect of PM2.5 exposure on CRC. We searched PubMed, Web of Science, and Google Scholar databases for population-based articles published before September 2022, providing risk estimates with 95% confidence intervals (CI). Among 85,743 articles, we identified 10 eligible studies across multiple countries and regions in North America and Asia. We calculated the overall risk, incidence and mortality and performed subgroup analyses according to countries and regions. The results revealed an association between PM2.5 and increased risk of CRC (total risk, 1.19 [95% CI 1.12-1.28]; incidence, OR=1.18 [95% CI 1.09-1.28]; mortality, OR=1.21 [95% CI 1.09-1.35]). The elevated risks of CRC associated with PM2.5 were different across countries and regions, at 1.34 [95% CI 1.20-1.49], 1.00 [95% CI 1.00-1.00], 1.08 [95% CI 1.06-1.10], 1.18 [95% CI 1.07-1.29], 1.01 [95% CI 0.79-1.30], in the United States, China, Taiwan, Thailand, and Hong Kong, respectively. Incidence and mortality risks were higher in North America than those in Asia. In particular, the incidence and mortality were highest in the United States (1.61 [95% CI 1.38-1.89] and 1.29 [95% CI 1.17-1.42], respectively) than those in other countries. This study is the first comprehensive meta-analysis to find a strong association between PM2.5 exposure and increased CRC risk.
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Delayed bone defect repairs lead to severe health and socioeconomic impacts on patients. Hence, there are increasing demands for medical interventions to promote bone defect healing. Recombinant proteins such as BMP-2 have been recognized as one of the powerful osteogenic substances that promote mesenchymal stem cells (MSCs) to osteoblast differentiation and are widely applied clinically for bone defect repairs. However, recent reports show that BMP-2 treatment has been associated with clinical adverse side effects such as ectopic bone formation, osteolysis and stimulation of inflammation. Here, we have identified one new osteogenic protein, named 'HKUOT-S2' protein, from Dioscorea opposita Thunb. Using the bone defect model, we have shown that the HKUOT-S2 protein can accelerate bone defect repair by activating the mTOR signaling axis of MSCs-derived osteoblasts and increasing osteoblastic biomineralization. The HKUOT-S2 protein can also modulate the transcriptomic changes of macrophages, stem cells, and osteoblasts, thereby enhancing the crosstalk between the polarized macrophages and MSCs-osteoblast differentiation to facilitate osteogenesis. Furthermore, this protein had no toxic effects in vivo. We have also identified HKUOT-S2 peptide sequence TKSSLPGQTK as a functional osteogenic unit that can promote osteoblast differentiation in vitro. The HKUOT-S2 protein with robust osteogenic activity could be a potential alternative osteoanabolic agent for promoting osteogenesis and bone defect repairs. We believe that the HKUOT-S2 protein may potentially be applied clinically as a new class of osteogenic agent for bone defect healing.
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The pathogenesis of Sjögren's syndrome (SS) is poorly understood. To evaluate an autoimmunization-induced experimental SS model, we firstly observed the phenotype of lymphocyte infiltration in the enlarged submandibular gland (SG). Furthermore, significant activation of caspase-3 and a high ratio of Bax-to-Bcl-2 were detected, indicating the inflammatory apoptosis associated with developmental foci. Meanwhile, the dysregulated cytokines, such as tumor necrosis factor α, IL-1ß and IL-6 mRNA expression, were found to be over-expressed. A progressive decrease of aquaporin 5 and its subcellular translocation from apical to basal membrane in SG was found to be associated with the abnormally expressed M3 muscarinic acetylcholine receptor. This pattern was found to be similar to that seen in human SS and possibly contributed to the saliva secretion deficiency. Thus, this autoimmunization-induced model recapitulates the key features of human SS and may have potential for studying the pathogenesis of human SS.
Assuntos
Modelos Animais de Doenças , Síndrome de Sjogren/imunologia , Síndrome de Sjogren/patologia , Animais , Apoptose/imunologia , Aquaporina 5/antagonistas & inibidores , Aquaporina 5/metabolismo , Células Cultivadas , Feminino , Humanos , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Linfócitos/imunologia , Linfócitos/patologia , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Baço/patologia , Glândula Submandibular/patologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/farmacologiaRESUMO
Pancreatic cancer is amongst the most lethal malignancies, while its poor prognosis could be associated with promotion of autophagy and the tumor immune microenvironment. Studies have confirmed the pro-tumorigenic nature of the cathelicidin family of peptide LL-37 in several types of cancer. However, at higher doses, LL-37 exerts significant cytotoxicity against gastrointestinal cancer cells. In our study, we investigated the anti-tumorigenic potential of LL-37 in pancreatic cancer and the underlying mechanisms. Our results have shown that LL-37 inhibited the growth of pancreatic cancer both in vitro and in vivo. Mechanistic studies have demonstrated that LL-37 induced DNA damage and cell cycle arrest through induction of reactive oxygen species (ROS). Further study indicates that LL-37 suppressed autophagy in pancreatic cancer cells through activation of mTOR signaling, leading to more accumulation of ROS production and induction of mitochondrial dysfunctions. With combined treatment of LL-37 with the mTOR inhibitor rapamycin, LL-37-induced ROS production and cancer cell growth inhibition were attenuated. Subsequent in vivo study has shown that LL-37 downregulated the immunosuppressive myeloid-derived suppressor cells and M2 macrophages while upregulated the anti-cancer effectors CD8+ and CD4+ T cells in the tumor microenvironment. By using an in vitro co-culture system, it was shown that promotion of M2 macrophage polarization would be suppressed by LL-37 with inhibition of autophagy, which possessed significant negative impact on cancer growth. Taken together, our findings implicate that LL-37 could attenuate the development of pancreatic cancer by suppressing autophagy and reprogramming of the tumor immune microenvironment.
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BACKGROUND: Since the outbreak of COVID-19 has resulted in over 313,000,000 confirmed cases of infection and over 5,500,000 deaths, substantial research work has been conducted to discover agents/ vaccines against COVID-19. Undesired adverse effects were observed in clinical practice and common vaccines do not protect the nasal tissue. An increasing volume of direct evidence based on clinical studies of traditional Chinese medicines (TCM) in the treatment of COVID-19 has been reported. However, the safe anti-inflammatory and anti-fibrotic proprietary Chinese medicines nasal spray, designated as Allergic Rhinitis Nose Drops (ARND), and its potential of re-purposing for suppressing viral infection via SARS-CoV-2 RBD (Delta)- angiotensin converting enzyme 2 (ACE2) binding have not been elucidated. PURPOSE: To characterize ARND as a potential SARS-CoV-2 entry inhibitor for its possible preventive application in anti-virus hygienic agent. METHODS: Network pharmacology analysis of ARND was adopted to asacertain gene targets which were commonly affected by COVID-19. The inhibitory effect of ARND on viral infection was determined by an in vitro pseudovirus assay. Furthermore, ARND was confirmed to have a strong binding affinity with ACE2 and SARS-CoV-2 spike-RBD (Delta) by ELISA. Finally, inflammatory and fibrotic cell models were used in conjunction in this study. RESULTS: The results suggested ARND not only inhibited pseudovirus infection and undermined the binding affinity between ACE2 and the Spike protein (Delta), but also attenuated the inflammatory response upon infection and may lead to a better prognosis with a lower risk of pulmonary fibrosis. The data in this study also provide a basis for further development of ARND as an antiviral hygienic product and further investigations on ARND in the live virus, in vivo and COVID-19 patients. ARND holds promise for use in the current COVID-19 outbreak as well as in future pandemics. CONCLUSION: ARND could be considered as a safe anti-SARS-CoV-2 agent with potential to prevent SARS-CoV-2 coronavirus infection.
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Colorectal cancer (CRC) is an aggressive cancer. Isoalantolactone (IATL) has been reported to exert cytotoxicity against various cancer cells, but not CRC. In this study, we explored the anti-CRC effects and mechanism of action of IATL in vitro and in vivo. Our results demonstrated that IATL inhibited proliferation by inducing G0/G1 phase cell cycle arrest, apoptosis and autophagy in CRC cells. Repression of autophagy with autophagy inhibitors chloroquine (CQ) and Bafilomycin A1 (Baf-A1) enhanced the anti-CRC effects of IATL, suggesting that IATL induces cytoprotective autophagy in CRC cells. Mechanistic studies revealed that IATL lowered protein levels of phospho-AKT (Ser473), phospho-mTOR (Ser2448), phospho-70S6K (Thr421/Ser424) in CRC cells. Inhibition of AKT and mTOR activities using LY294002 and rapamycin, respectively, potentiated the inductive effects of IATL on autophagy and cell death. In vivo studies showed that IATL suppressed HCT116 tumor growth without affecting the body weight of mice. In consistent with the in vitro results, IATL lowered protein levels of Bcl-2, Bcl-XL, phospho-AKT (Ser473), phospho-mTOR (Ser2448), and phsopho-70S6K (Thr421/Ser424), whereas upregulated protein levels of cleaved-PARP and LC3B-II in HCT116 tumors. Collectively, our results demonstrated that in addition to inhibiting proliferation, inducing G0/G1-phase cell cycle arrest and apoptosis, IATL initiates cytoprotective autophagy in CRC cells by inhibiting the AKT/mTOR signaling pathway. These findings provide an experimental basis for the evaluation of IATL as a novel medication for CRC treatment.
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OBJECTIVE: To study the effects of total ginsenosides (TG) extract from Panax ginseng on neural stem cell (NSC) proliferation and differentiation and their underlying mechanisms. METHODS: The migration of NSCs after treatment with various concentrations of TG extract (50, 100, or 200 µ g/mL) were monitored. The proliferation of NSCs was examined by a combination of cell counting kit-8 and neurosphere assays. NSC differentiation mediated by TG extract was evaluated by Western blotting and immunofluorescence staining to monitor the expression of nestin and microtubule associated protein 2 (MAP2). The GSK-3ß/ß-catenin pathway in TG-treated NSCs was examined by Western blot assay. The NSCs with constitutively active GSK-3ß mutant were made by adenovirus-mediated gene transfection, then the proliferation and differentiation of NSCs mediated by TG were further verified. RESULTS: TG treatment significantly enhanced NSC migration (P<0.01 or P<0.05) and increased the proliferation of NSCs (P<0.01 or P<0.05). TG mediation also significantly upregulated MAP2 expression but downregulated nestin expression (P<0.01 or P<0.05). TG extract also significantly induced GSK-3ß phosphorylation at Ser9, leading to GSK-3ß inactivation and, consequently, the activation of the GSK-3ß/ß-catenin pathway (P<0.01 or P<0.05). In addition, constitutive activation of GSK-3ß in NSCs by the transfection of GSK-3ß S9A mutant was found to significantly suppress TG-mediated NSC proliferation and differentiation (P<0.01 or P<0.05). CONCLUSION: TG promoted NSC proliferation and neuronal differentiation by inactivating GSK-3ß.
Assuntos
Ginsenosídeos , Células-Tronco Neurais , Panax , Animais , Diferenciação Celular , Proliferação de Células , Ginsenosídeos/farmacologia , Glicogênio Sintase Quinase 3 beta/metabolismo , Células-Tronco Neurais/metabolismo , Extratos Vegetais/farmacologia , Ratos , beta Catenina/metabolismoRESUMO
This review covers the biosynthesis of glyceollin and its biological activities including antiproliferative/antitumor action (toward B16 melanoma cells, LNCaP prostate cancer cells, and BG-1 ovarian cancer cells), anti-estrogenic action (through estrogen receptors α- and ß-), antibacterial action (toward Erwinia carotovora, Escherichia coli, Bradyrhizobium japonicum, Sinorhizobium fredii ), antinematode activity, and antifungal activity (toward Fusarium solani, Phakospora pachyrhizi, Diaporthe phaseolorum, Macrophomina phaseolina, Sclerotina sclerotiorum, Phytophthora sojae, Cercospora sojina, Phialophora gregata, and Rhizoctonia solani). Other activities include insulinotropic action and attenuation of vascular contractions in rat aorta.
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Anti-Infecciosos/farmacologia , Antineoplásicos/farmacologia , Glycine max/química , Pterocarpanos/farmacologia , Sesquiterpenos/farmacologia , Animais , Anti-Infecciosos/metabolismo , Antineoplásicos/metabolismo , Tratamento Farmacológico , Humanos , Pterocarpanos/biossíntese , Sesquiterpenos/metabolismo , Glycine max/metabolismo , FitoalexinasRESUMO
Aggregated beta-amyloid (Aß) and elevated plasma levels of homocysteine have been implicated as critical factors in the pathogenesis of Alzheimer's disease. The neuroprotective effects and possible mechanism of four structurally similar dibenzocyclooctadiene lignans (namely schisandrin, schisantherin A, schisandrin B and schisandrin C) isolated from the fruit of Schisandra chinensis (Turcz.) Baill. (Schisandraceae) against Aß25â35 and homocysteine toxicity in PC12 cells was studied. Exposure of PC12 cells to 0.5 µm Aß25â35 caused significant cell death, increased the number of apoptotic cells, elevated reactive oxygen species, increased the levels of the pro-apoptotic protein Bax and caspase-3 activation. All these effects induced by Aß25â35 were markedly reversed by schisandrin B and schisandrin C pretreatment, while schisandrin and schisantherin A had no obvious effects. Meanwhile, schisandrin B and schisandrin C reversed homocysteine-induced cytotoxicity. The results indicated that schisandrin B and schisandrin C protected PC12 cells against Aß toxicity by attenuating ROS production and modulating the apoptotic signal pathway through Bax and caspase-3. Further structure-activity analysis of Schisandra lignans and evaluations of their neuroprotective effects using AD animal models are warranted.
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Peptídeos beta-Amiloides/toxicidade , Ciclo-Octanos/farmacologia , Homocisteína/toxicidade , Lignanas/farmacologia , Fármacos Neuroprotetores/farmacologia , Fragmentos de Peptídeos/toxicidade , Schisandra/química , Animais , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Dioxóis , Células PC12 , Compostos Policíclicos , Ratos , Espécies Reativas de Oxigênio/metabolismo , Proteína X Associada a bcl-2/metabolismoRESUMO
An-Gong-Niu-Huang Wan (AGNHW), a famous formula in traditional Chinese medicine, has been clinically used for centuries for treating cerebral diseases, but the protective effects of pre-treatment with AGNHW on cerebral ischemia have not yet been reported. The present study aimed to test such protective effects and elucidate the underlying mechanisms on cerebral ischemia in rats by phenotypic approaches (i.e. including the neurological functional score, cerebral infarct area, neuron apoptosis, and brain oxidative stress status) and target-based approaches (i.e. involving the GSK-3ß/HO-1 pathway). AGNHW was administered orally at the doses of 386.26, 772.52, and 1545.04 mg/kg respectively for 7 days to male Sprague-Dawley rats and then cerebral ischemia was induced by middle cerebral artery occlusion (MCAO) for 1.5 h. Pre-treatment with AGNHW significantly ameliorated ischemic damage to the brain in a dose-dependent manner, including reduction of the neurological deficit score and infarct area. AGNHW pre-treatment increased the number of Nissl+ cells, NeuN+ and DCX+ cells, and decreased the number of Tunel+ cells. Moreover, AGNHW reversed the up-regulation of ROS and MDA induced by cerebral ischemia. AGNHW pre-treatment increased the expression of p-GSK-3ß(Ser9)/GSK-3ß (glycogen synthase kinase-3ß) ratio and heme oxygenase-1 (HO-1). These results firstly revealed that short-term pre-treatment of AGNHW could significantly protect the rats from injury caused by cerebral ischemia-reperfusion, which support further clinical studies for disease prevention. The in vivo protective effect of AGNWH pre-treatment could be associated with its antioxidant properties by the activation of GSK-3ß-mediated HO-1 pathway.
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BACKGROUND: Alzheimer's disease (AD) is one of the most prevalent neurodegenerative disorders. Enhancing hippocampal neurogenesis by promoting proliferation and differentiation of neural stem cells (NSCs) is a promising therapeutic strategy for AD. 20(S)-protopanaxadiol (PPD) and oleanolic acid (OA) are small, bioactive compounds found in ginseng that can promote NSC proliferation and neural differentiation in vitro. However, it is currently unknown whether PPD or OA can attenuate cognitive deficits by enhancing hippocampal neurogenesis in vivo in a transgenic APP/PS1 AD mouse model. Here, we administered PPD or OA to APP/PS1 mice and monitored the effects on cognition and hippocampal neurogenesis. METHODS: We used the Morris water maze, Y maze, and open field tests to compare the cognitive capacities of treated and untreated APP/PS1 mice. We investigated hippocampal neurogenesis using Nissl staining and BrdU/NeuN double labeling. NSC proliferation was quantified by Sox2 labeling of the hippocampal dentate gyrus. We used western blotting to determine the effects of PPD and OA on Wnt/GSK3ß/ß-catenin pathway activation in the hippocampus. RESULTS: Both PPD and OA significantly ameliorated the cognitive impairments observed in untreated APP/PS1 mice. Furthermore, PPD and OA significantly promoted hippocampal neurogenesis and NSC proliferation. At the mechanistic level, PPD and OA treatments resulted in Wnt/GSK-3ß/ß-catenin pathway activation in the hippocampus. CONCLUSION: PPD and OA ameliorate cognitive deficits in APP/PS1 mice by enhancing hippocampal neurogenesis, achieved by stimulating the Wnt/GSK-3ß/ß-catenin pathway. As such, PPD and OA are promising novel therapeutic agents for the treatment of AD and other neurodegenerative diseases.
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A simple method based on liquid chromatography coupled with diode array detection and electrospray ionization mass spectrometry (LC-DAD-ESI-MS) was developed for the quality assessment of Cortex Phellodendri (CP), which was mainly derived from two species of Phellodendron chinense Schneid and Phellodendron amurense Rupr. Total 41 compounds, including 14 phenols, 24 alkaloids and three liminoidal triterpenes were identified or tentatively characterized from the 75% methanol extract of CP samples by online ESI-MS(n) fragmentation and UV spectra analysis. Among them, two phenols and six alkaloids were simultaneously quantified using HPLC-DAD method. The validated HPLC-DAD method showed a good linearity, precision, repeatability and accuracy for the quantification of eight marker compounds. Furthermore, the plausible fragmentation pathway of the representative compounds were proposed in the present study. The differences of the chemical constituents content and the comprehensive HPLC profiles between the two CP species using LC-DAD-ESI-MS method are reported for the first time, indicating that the CP drugs from different resources should be used separately in the clinic.
Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/análise , Phellodendron/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Alcaloides/análise , Alcaloides/química , Biomarcadores/análise , Biomarcadores/química , Medicamentos de Ervas Chinesas/química , Modelos Lineares , Fenóis/análise , Fenóis/química , Casca de Planta/química , Reprodutibilidade dos Testes , Triterpenos/análise , Triterpenos/químicaRESUMO
The use of bilberry (Vaccinium myrtillus L.) as a food and medicine for improving human vision has a long history all over the world. However, there is lack of convincing evidence from rigorous clinical trials or scientific research. This study investigated the effects of different concentrations of bilberry extracts on the cell viability, cell cycle and the expression of hyaluronic acid and glycosaminoglycans of cultured human corneal limbal epithelial cells. The data showed that bilberry extracts had no cytotoxicity to the corneal limbal epithelial cells at a wide range of concentrations (10(-9)-10(-4) M, equalized to the content of cyanidin-3-O-glucoside). Bilberry extract (10(-6), 10(-5) and 10(-4) M) increased cell viability after 48 h incubation. The number of cells decreased in G(0)/G(1) phase and increased prominently in S and G(2)/M phases after treatment with bilberry extracts at a high concentration (10(-4) M). The expression of glycosaminoglycans increased prominently after incubation with bilberry extracts (10(-7) and 10(-4) M) for 48 h while no significant changes were observed for the expression of hyaluronic acid. The results indicated that bilberry extract may be beneficial for the physiological renewal and homeostasis of corneal epithelial cells.