RESUMEN
Minimal hepatic encephalopathy (MHE) was characterized for cognitive dysfunction. Insulin resistance (IR) has been identified to be correlated with the pathogenesis of MHE. Oridonin (Ori) is an active terpenoid, which has been reported to rescue synaptic loss and restore insulin sensitivity. In this study, we found that intraperitoneal injection of Ori rescued IR, reduced the autophagosome formation and synaptic loss and improved cognitive dysfunction in MHE rats. Moreover, in insulin-resistant PC12 cells and N2a cells, we found that Ori blocked IR-induced synaptic deficits via the down-regulation of PTEN, the phosphorylation of Akt and the inhibition of autophagy. Taken together, these results suggested that Ori displays therapeutic efficacy towards memory deficits via improvement of IR in MHE and represents a novel bioactive therapeutic agent for treating MHE.
Asunto(s)
Disfunción Cognitiva/prevención & control , Diterpenos de Tipo Kaurano/farmacología , Encefalopatía Hepática/complicaciones , Resistencia a la Insulina , Trastornos de la Memoria/prevención & control , Fosfohidrolasa PTEN/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Animales , Autofagia , Disfunción Cognitiva/etiología , Disfunción Cognitiva/metabolismo , Disfunción Cognitiva/patología , Encefalopatía Hepática/patología , Trastornos de la Memoria/etiología , Trastornos de la Memoria/metabolismo , Trastornos de la Memoria/patología , Fosfohidrolasa PTEN/genética , Fosforilación , Proteínas Proto-Oncogénicas c-akt/genética , Ratas , Ratas Sprague-DawleyRESUMEN
It has been demonstrated that the action of dopamine (DA) could enhance the production of tumour necrosis factor-α (TNF-α) by astrocytes and potentiate neuronal apoptosis in minimal hepatic encephalopathy (MHE). Recently, sodium hydrosulfide (NaHS) has been found to have neuroprotective properties. Our study addressed whether NaHS could rescue DA-challenged inflammation and apoptosis in neurons to ameliorate memory impairment in MHE rats and in the neuron and astrocyte coculture system. We found that NaHS suppressed DA-induced p65 acetylation, resulting in reduced TNF-α production in astrocytes both in vitro and in vivo. Furthermore, decreased apoptosis was observed in neurons exposed to conditioned medium from DA + NaHS-challenged astrocytes, which was similar to the results obtained in the neurons exposed to TNF-α + NaHS, suggesting a therapeutic effect of NaHS on the suppression of neuronal apoptosis via the reduction of TNF-α level. DA triggered the inactivation of p70 S6 ribosomal kinase (S6K1) and dephosphorylation of Bad, resulting in the disaggregation of Bclxl and Bak and the release of cytochrome c (Cyt. c), and this process could be reversed by NaHS administration. Our work demonstrated that NaHS attenuated DA-induced astrocytic TNF-α release and ameliorated inflammation-induced neuronal apoptosis in MHE. Further research into this approach may uncover future potential therapeutic strategies for MHE.
Asunto(s)
Astrocitos/efectos de los fármacos , Astrocitos/metabolismo , Dopamina/efectos adversos , Encefalopatía Hepática/complicaciones , Encefalopatía Hepática/metabolismo , Sulfuro de Hidrógeno/farmacología , Enfermedades Neurodegenerativas/etiología , Animales , Apoptosis/efectos de los fármacos , Conducta Animal/efectos de los fármacos , Biomarcadores , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Encéfalo/patología , Cognición/efectos de los fármacos , Disfunción Cognitiva/tratamiento farmacológico , Disfunción Cognitiva/etiología , Disfunción Cognitiva/metabolismo , Susceptibilidad a Enfermedades , Dopamina/metabolismo , Encefalopatía Hepática/patología , Enfermedades Neurodegenerativas/tratamiento farmacológico , Enfermedades Neurodegenerativas/metabolismo , Enfermedades Neurodegenerativas/patología , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Fosforilación/efectos de los fármacos , Unión Proteica , Ratas , Factor de Necrosis Tumoral alfa/metabolismo , Proteína Letal Asociada a bcl/metabolismo , Proteína bcl-X/metabolismoRESUMEN
Carbon-silica materials with hierarchical pores consisting of micropores and mesopores were prepared by introducing nanocarbon microspheres derived from biomass sugar into silica gel channels in a hydrothermal environment. The physicochemical properties of the materials were characterized by nitrogen physical adsorption (BET), scanning electron microscopy (SEM), and thermogravimetric (TG), and the adsorption properties of various organic waste gases were investigated. The results showed that microporous carbon materials were introduced successfully into the silica gel channels, thus showing the high adsorption capacity of activated carbon in high humidity organic waste gas, and the high stability and mechanical strength of the silica gel. The dynamic adsorption behavior confirmed that the carbon-silica material had excellent adsorption capacity for different volatile organic compounds (VOCs). Furthermore, the carbon-silica material exhibited excellent desorption characteristics: adsorbed toluene was completely desorbed at 150°C, thereby showing superior regeneration characteristics. Both features were attributed to the formation of hierarchical pores.
Asunto(s)
Modelos Químicos , Compuestos Orgánicos Volátiles/química , Adsorción , Biomasa , Carbón Orgánico , Humedad , Interacciones Hidrofóbicas e Hidrofílicas , Microesferas , Porosidad , Dióxido de Silicio/química , Tolueno/químicaRESUMEN
Accurate partitioning of chromosomes during mitosis is essential for genetic stability and requires the assembly of the dynamic mitotic spindle and proper kinetochore-microtubule attachment. The spindle assembly checkpoint (SAC) monitors the incompleteness and errors in kinetochore-microtubule attachment and delays anaphase. The SAC kinase Mps1 regulates the recruitment of downstream effectors to unattached kinetochores. Mps1 also actively promotes chromosome alignment during metaphase, but the underlying mechanism is not completely understood. Here, we show that Mps1 regulates chromosome alignment through MCRS1, a spindle assembly factor that controls the dynamics of the minus end of kinetochore microtubules. Mps1 binds and phosphorylates MCRS1. This mechanism enables KIF2A localization to the minus end of spindle microtubules. Thus, our study reveals a novel role of Mps1 in regulating the dynamics of the minus end of microtubules and expands the functions of Mps1 in genome maintenance.