RESUMEN
Although in-vivo exposure of PM2.5 has been suggested to initiate a disorder on vascular permeability, the effects and related mechanism has not been well defined. In this work, an obvious increase on vascular permeability has been confirmed in vivo by vein injection of PM2.5 into Balb/c mouse. Human umbilical vein vascular endothelial cells and the consisted ex-vivo vascular endothelium were used as model to investigate the effects of PM2.5 on the vascular permeability and the underlying molecular mechanism. Upon PM2.5 exposure, the vascular endothelial growth factor receptor 2 on cell membrane phosphorylates and activates the downstream mitogen-activated protein kinase (MAPK)/ERK signaling. The adherens junction protein VE-cadherin sheds and the intercellular junction opens, damaging the integrity of vascular endothelium via paracellular pathway. Besides, PM2.5 induces the intracellular reactive oxygen species (ROS) production and triggers the oxidative stress including activity decrease of superoxide dismutase, lactate dehydrogenase release and permeability increase of cell membrane. Taken together, the paracellular and transcellular permeability enhancement jointly contributes to the significant increase of endothelium permeability and thus vascular permeability upon PM2.5 exposure. This work provides an insight into molecular mechanism of PM2.5 associated cardiovascular disease and offered a real-time screening method for the health risk of PM2.5.
Asunto(s)
Permeabilidad Capilar/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Material Particulado/toxicidad , Especies Reactivas de Oxígeno/metabolismo , Acetilcisteína/farmacología , Uniones Adherentes/efectos de los fármacos , Animales , Antígenos CD/metabolismo , Butadienos/farmacología , Cadherinas/metabolismo , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Humanos , Uniones Intercelulares/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos BALB C , Nitrilos/farmacología , Estrés Oxidativo/efectos de los fármacosRESUMEN
Biological soil crusts (biocrusts) play an important role in soil nutrient accumulation and cycling. We examined the relationship between soil nutrient characters and biocrusts types, with six typical types of biocrusts in the hilly Loess Plateau region, including light cyanobacterial crust, dark cyanobacterial crust, cyanobacterial with moss crust (mixed crusts), moss crust, Diploschistes spp. crust, and Nostoc commune crust. The variations of soil carbon (C), nitrogen (N), phospho-rus (P) concentrations and stoichiometric ratios of biocrustal layer and the subsoil under different types of biocrusts were investigated. The results showed that there were significant differences in C, N, P concentrations and stoichiometric ratio among different biocrusts types. The concentrations and stoichiometric ratios of C, N, P in the biocrustal layer were significantly higher than those of 0-10 cm soil beneath biocrusts. The concentrations of C and N significantly decreased with the increases of soil depth across all the biocrusts types. P content showed no variation between soil layers. The concentrations and stoichiometric ratios of C, N, P of moss crust were significantly higher than those of other biocrusts,with C, N, and P content of 27.07, 2.42 and 0.67 g·kg-1. In soil layer of 0-2 cm, the concentrations and stoichiometric ratios of C, N, P under N. commune crust were significantly higher than those of other biocrusts.
Asunto(s)
Ecosistema , Microbiología del Suelo , Suelo , China , EcologíaRESUMEN
Regulating apoptosis of lymphocytes is an effective strategy for treatment of lymphocyte-mediated diseases. Recently it has been demonstrated that augmenter of liver regeneration (ALR), an enigmatic protein presented ubiquitously in multiple forms among eukaryotes, possesses potent anti-apoptotic activity and supports proliferation of a variety of cells. However, its action on lymphocytes and the underlying mechanism are not completely understood. In this study, we analyzed the effects of recombinant human ALR (rhALR) on apoptosis of human lymphocytes activated with concanavalin A (ConA). Our results showed that rhALR inhibited apoptosis of ConA-activated lymphocytes and revealed reductions in the percentage of apoptotic cells, caspase-3 activation and PARP cleavage in cells treated with rhALR. Furthermore, the BAX/BCL-2 and cytosol/mitochondria cytochrome c ratios were decreased in the intrinsic death pathway and the activation of caspase-8 was also decreased in the extrinsic death pathway in activated lymphocytes treated with rhALR. In addition, rhALR significantly reduced the quantity of interleukin-2. These results demonstrated that rhALR has anti-apoptotic effects on activated lymphocytes through the activation of several apoptosis-related signaling pathways, and shed some light on the effects of rhALR on modulation immune reactions.
Asunto(s)
Apoptosis/efectos de los fármacos , Reductasas del Citocromo/farmacología , Regeneración Hepática/efectos de los fármacos , Linfocitos/efectos de los fármacos , Linfocitos/patología , Apoptosis/fisiología , Caspasa 3/metabolismo , Caspasa 8/metabolismo , Concanavalina A/farmacología , Citocromos c/metabolismo , Citosol/efectos de los fármacos , Citosol/metabolismo , Citosol/fisiología , Humanos , Interleucina-2/metabolismo , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/metabolismo , Leucocitos Mononucleares/fisiología , Regeneración Hepática/fisiología , Linfocitos/metabolismo , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Mitocondrias/fisiología , Oxidorreductasas actuantes sobre Donantes de Grupos Sulfuro , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteínas Recombinantes/farmacología , Proteína X Asociada a bcl-2/metabolismoRESUMEN
AIM: To develop a quantitative ELISA by measuring interferon (IFN-gamma) of equine lymphocytes. METHODS: Sandwich ELISA for equine IFN-gamma was developed using mAb A5 as a capture antibody and biotinylated mAb SB10 as a detection antibody. RESULTS: The detection limit of the sandwich ELISA for equine IFN-gamma was 1 microg/L and did not show cross-reactivity with recombinant equine IL-18. Equine IFN-gamma was detected by ELISA in culture medium of the peripheral blood mononuclear cells (PBMCs) stimulated with ConA or PMA/Ionomycin. CONCLUSION: This method can be used to help understand the role of this cytokine in various equine diseases and develop specific cell-mediated immunity assay.