Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 20
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
Environ Sci Pollut Res Int ; 30(37): 87215-87227, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37420156

RESUMEN

Low biological hydrogen (bioH2) production due to non-optimal metabolic pathways occurs frequently. In this work, magnetic nitrogen-doped activated carbon (MNAC) was prepared and added into the inoculated sludge with glucose as substrate to enhance hydrogen (H2) yield by mesophilic dark fermentation (DF). The highest H2 yield appeared in 400 mg/L AC (252.8 mL/g glucose) and 600 mg/L MNAC group (304.8 mL/g glucose), which were 26.02% and 51.94% higher than that of 0 mg/L MNAC group (200.6 mL/g glucose). The addition of MNAC allowed for efficient enrichment of Firmicutes and Clostridium-sensu-stricto-1, accelerating the metabolic pathway shifted towards butyrate type. The Fe ions released by MNAC facilitated electron transfer and favored the reduction of ferredoxin (Fd), thereby obtaining more bioH2. Finally, the generation of [Fe-Fe] hydrogenase and cellular components of H2-producing microbes (HPM) during homeostasis was discussed to understand on the use of MNAC in DF system.


Asunto(s)
Carbón Orgánico , Hidrógeno , Fermentación , Hidrógeno/metabolismo , Glucosa , Fenómenos Magnéticos , Reactores Biológicos
2.
JACC Basic Transl Sci ; 7(3): 247-261, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35411318

RESUMEN

Bleeding associated with left ventricular assist device (LVAD) implantation has been attributed to the loss of large von Willebrand factor (VWF) multimers to excessive cleavage by ADAMTS-13, but this mechanism is not fully supported by the current evidence. We analyzed VWF reactivity in longitudinal samples from LVAD patients and studied normal VWF and platelets exposed to high shear stress to show that VWF became hyperadhesive in LVAD patients to induce platelet microvesiculation. Platelet microvesicles activated endothelial cells, induced vascular permeability, and promoted angiogenesis in a VWF-dependent manner. Our findings suggest that LVAD-driven high shear stress primarily activates VWF, rather than inducing cleavage in the majority of patients.

3.
Iran J Public Health ; 51(12): 2773-2782, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36742226

RESUMEN

Background: Osteosarcoma is the most common primary malignant tumor of bone. Abnormal expression of S100A1 protein is closely related to the occurrence and development of malignant tumors. However, S100A1 in osteosarcoma has not been studied. Methods: All osteosarcoma tissues were collected from patients who received surgical therapy at the Affiliated Hospital of Inner Mongolia Medical University, China in 2020. QRT-PCR and western blot assays were used to detect the expression of S100A1 in osteosarcoma tissues and cells. The negative effect of S100A1 on osteosarcoma cell growth was confirmed by vitro and vivo experiments. Results: S100A1 inhibited the growth of osteosarcoma cells in vitro. Overexpression of S100A1 may inhibit the proliferation of osteosarcoma cells by preventing the activation of AKT signaling pathway by western blot assay. Finally, animal experiments confirmed that overexpression of S100A1 could inhibit the proliferation of osteosarcoma cells. Overexpression of S100A1 obtained better survival benefit in mice. Conclusion: Our findings provided a new insight to the treatment of osteosarcoma. It also raised the possibility that S100A1 could be used in targeted therapies for osteosarcoma.

4.
Blood ; 138(25): 2714-2726, 2021 12 23.
Artículo en Inglés | MEDLINE | ID: mdl-34610086

RESUMEN

Severe traumatic brain injury (TBI) often causes an acute systemic hypercoagulable state that rapidly develops into consumptive coagulopathy. We have recently demonstrated that TBI-induced coagulopathy (TBI-IC) is initiated and disseminated by brain-derived extracellular vesicles (BDEVs) and propagated by extracellular vesicles (EVs) from endothelial cells and platelets. Here, we present results from a study designed to test the hypothesis that anticoagulation targeting anionic phospholipid-expressing EVs prevents TBI-IC and improves the outcomes of mice subjected to severe TBI. We evaluated the effects of a fusion protein (ANV-6L15) for improving the outcomes of TBI in mouse models combined with in vitro experiments. ANV-6L15 combines the phosphatidylserine (PS)-binding annexin V (ANV) with a peptide anticoagulant modified to preferentially target extrinsic coagulation. We found that ANV-6L15 reduced intracranial hematoma by 70.2%, improved neurological function, and reduced death by 56.8% in mice subjected to fluid percussion injury at 1.9 atm. It protected the TBI mice by preventing vascular leakage, tissue edema, and the TBI-induced hypercoagulable state. We further showed that the extrinsic tenase complex was formed on the surfaces of circulating EVs, with the highest level found on BDEVs. The phospholipidomic analysis detected the highest levels of PS on BDEVs, as compared with EVs from endothelial cells and platelets (79.1, 15.2, and 3.5 nM/mg of protein, respectively). These findings demonstrate that TBI-IC results from a trauma-induced hypercoagulable state and may be treated by anticoagulation targeting on the anionic phospholipid-expressing membrane of EVs from the brain and other cells.


Asunto(s)
Anexina A5/uso terapéutico , Anticoagulantes/uso terapéutico , Lesiones Traumáticas del Encéfalo/tratamiento farmacológico , Vesículas Extracelulares/efectos de los fármacos , Fosfolípidos/metabolismo , Proteínas Recombinantes de Fusión/uso terapéutico , Trombofilia/tratamiento farmacológico , Animales , Lesiones Traumáticas del Encéfalo/complicaciones , Lesiones Traumáticas del Encéfalo/metabolismo , Lesiones Traumáticas del Encéfalo/patología , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/patología , Masculino , Ratones Endogámicos C57BL , Trombofilia/etiología , Trombofilia/metabolismo , Trombofilia/patología
5.
Blood ; 137(4): 544-555, 2021 01 28.
Artículo en Inglés | MEDLINE | ID: mdl-33507292

RESUMEN

Traumatic brain injury-induced coagulopathy (TBI-IC) causes life-threatening secondary intracranial bleeding. Its pathogenesis differs mechanistically from that of coagulopathy arising from extracranial injuries and hemorrhagic shock, but it remains poorly understood. We report results of a study designed to test the hypothesis that von Willebrand factor (VWF) released during acute TBI is intrinsically hyperadhesive because its platelet-binding A1-domain is exposed and contributes to TBI-induced vascular leakage and consumptive coagulopathy. This hyperadhesive VWF can be selectively blocked by a VWF A2-domain protein to prevent TBI-IC and to improve neurological function with a minimal risk of bleeding. We demonstrated that A2 given through intraperitoneal injection or IV infusion reduced TBI-induced death by >50% and significantly improved the neurological function of C57BL/6J male mice subjected to severe lateral fluid percussion injury. A2 protected the endothelium from extracellular vesicle-induced injury, reducing TBI-induced platelet activation and microvesiculation, and preventing a TBI-induced hypercoagulable state. A2 achieved this therapeutic efficacy by specifically blocking the A1 domain exposed on the hyperadhesive VWF released during acute TBI. These results suggest that VWF plays a causal role in the development of TBI-IC and is a therapeutic target for this life-threatening complication of TBI.


Asunto(s)
Lesiones Traumáticas del Encéfalo/tratamiento farmacológico , Fragmentos de Péptidos/farmacología , Factor de von Willebrand/antagonistas & inhibidores , Reacción de Fase Aguda , Animales , Plaquetas/metabolismo , Lesiones Traumáticas del Encéfalo/complicaciones , Síndrome de Fuga Capilar/etiología , Síndrome de Fuga Capilar/prevención & control , Estudios de Casos y Controles , Hemorragia Cerebral/etiología , Hemorragia Cerebral/prevención & control , Circulación Cerebrovascular , Coagulación Intravascular Diseminada/etiología , Coagulación Intravascular Diseminada/prevención & control , Endotelio Vascular/efectos de los fármacos , Vesículas Extracelulares , Humanos , Infusiones Intravenosas , Inyecciones Intraperitoneales , Masculino , Ratones , Ratones Endogámicos C57BL , Fragmentos de Péptidos/administración & dosificación , Fragmentos de Péptidos/uso terapéutico , Activación Plaquetaria/efectos de los fármacos , Conformación Proteica , Dominios Proteicos/efectos de los fármacos , Proteínas Recombinantes de Fusión/administración & dosificación , Proteínas Recombinantes de Fusión/farmacología , Proteínas Recombinantes de Fusión/uso terapéutico , Factor de von Willebrand/química , Factor de von Willebrand/fisiología , Factor de von Willebrand/uso terapéutico
6.
ACS Omega ; 5(16): 9151-9161, 2020 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-32363267

RESUMEN

Wheat straw was pretreated with either CaO2 or CaO to improve biohydrogen production. Both CaO and CaO2 pretreatments improved the biodegradability of the wheat straw. CaO pretreatment raised the H2 yield by between 48.8 and 163.9% at CaO contents ranging from 2 to 4%. The highest H2 yield [144 mL/g total solid (TS)] was obtained at 121 °C and 6% CaO. In addition, the highest H2 yield from wheat straw pretreated at the same temperature and dosage of CaO2 was 71.8 mL/g TS, which was higher than that of the control group (43.2 mL/g TS), with hot water (121 °C) treatment. Considering pretreatment costs and H2 production potential, CaO was a better pretreatment agent than CaO2.

7.
Brain Res ; 1732: 146682, 2020 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-31991122

RESUMEN

Traumatic brain injury (TBI) is one of the leading causes of mortality and disability worldwide. Emerging studies have shown that endoplasmic reticulum (ER) stress plays an important role in the pathophysiology of TBI. Dexmedetomidine (Dex), a highly selective α2-adrenoreceptor agonist, has been shown to attenuate ER stress. However, there is no relevant research in the field of TBI. To study the effects of dexmedetomidine on TBI, we subjected mice to TBI with a controlled cortical impact (CCI) device. The expression levels of ER stress marker proteins and apoptosis-related proteins were evaluated by western blotting and immunofluorescence. Neuronal cell death was assessed by a terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end-labelling (TUNEL) assay. Neurological and motor deficits were assessed by modified neurological severity scores (mNSSs) and beam balance and beam walking tests. Brain water content and EB leakage were also assessed. Our group found that ER stress was significantly activated 72 h after TBI. Dexmedetomidine significantly reduced ER stress and ER stress-related neuronal apoptosis induced by experimental TBI. In addition, dexmedetomidine significantly improved neurological function and alleviated brain oedema. These findings indicate that dexmedetomidine alleviates severe, post-traumatic ER stress and attenuates secondary brain damage.


Asunto(s)
Agonistas de Receptores Adrenérgicos alfa 2/farmacología , Apoptosis/efectos de los fármacos , Lesiones Traumáticas del Encéfalo/metabolismo , Dexmedetomidina/farmacología , Estrés del Retículo Endoplásmico/efectos de los fármacos , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Masculino , Ratones
8.
Mol Med Rep ; 20(3): 2703-2711, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31322192

RESUMEN

The present study explored whether miR­145­5p can aggravate the development and progression of rheumatoid arthritis (RA) by regulating the expression of matrix metalloproteinases (MMPs). ELISAs, reverse transcription­quantitative polymerase chain reaction (RT­qPCR), and western blotting were used to examine the expression levels of MMP­1, MMP­3, MMP­9, and MMP­13 in fibroblast­like synoviocytes (FLS) from patients with RA. Levels of MMP­1, MMP­3, MMP­9, and MMP­13 were assessed in the right hind ankles of a murine collagen­induced arthritis (CIA) model by RT­qPCR and immunohistochemical (IHC) analysis. The effects of activation or inhibition of the nuclear factor­κB (NF­κB) pathway on MMPs were evaluated by RT­qPCR and western blotting. Subcellular localization of NF­κB p65 was visualized by confocal microscopy. Overexpression of miR­145­5p increased the expression of MMP­3, MMP­9, and MMP­13 in RA­FLS. Moreover, injection of a miR­145­5p agomir into mice increased MMP­3, MMP­9, and MMP­13, as demonstrated by RT­qPCR and IHC analysis. A chemical inhibitor that selectively targets NF­κB (BAY11­7082) significantly attenuated MMP­9 expression, while it did not influence the levels of MMP­3 and MMP­13. Immunofluorescence analysis revealed that nuclear localization of p65 was significantly enhanced, indicating that miR­145­5p enhances activation of the NF­κB pathway by promoting p65 nuclear translocation. miR­145­5p overexpression also significantly increased phosphorylated p65 levels; however, the levels of IkB­a were reduced in response to this miRNA. Moreover, our results indicated that miR­145­5p aggravated RA progression by activating the NF­κB pathway, which enhanced secretion of MMP­9. In conclusion, modulation of miR­145­5p expression is potentially useful for the treatment of RA inflammation, by regulating the expression of MMPs, and MMP­9 in particular, through inhibition of the NF­κB pathway.


Asunto(s)
Artritis Reumatoide/genética , Metaloproteinasa 9 de la Matriz/genética , MicroARNs/genética , FN-kappa B/inmunología , Adulto , Animales , Artritis Reumatoide/inmunología , Artritis Reumatoide/patología , Células Cultivadas , Femenino , Humanos , Masculino , Metaloproteinasa 9 de la Matriz/inmunología , Ratones , MicroARNs/inmunología , Persona de Mediana Edad , Transducción de Señal , Regulación hacia Arriba , Adulto Joven
9.
Front Cell Neurosci ; 13: 117, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30971898

RESUMEN

Semaphorin 3A (SEMA3A) is a member of the Semaphorins family, a class of membrane-associated protein that participates in the construction of nerve networks. SEMA3A has been reported to affect vascular permeability previously, but its influence in traumatic brain injury (TBI) is still unknown. To investigate the effects of SEMA3A, we used a mouse TBI model with a controlled cortical impact (CCI) device and a blood-brain barrier (BBB) injury model in vitro with oxygen-glucose deprivation (OGD). We tested post-TBI changes in SEMA3A, and its related receptors (Nrp-1 and plexin-A1) expression and distribution through western blotting and double-immunofluorescence staining, respectively. Neurological outcomes were evaluated by modified neurological severity scores (mNSSs) and beam-walking test. We examined BBB damage through Evans Blue dye extravasation, brain water content, and western blotting for VE-cadherin and p-VE-cadherin in vivo, and we examined the endothelial cell barrier through hopping probe ion conductance microscopy (HPICM), transwell leakage, and western blotting for VE-cadherin and p-VE-cadherin in vitro. Changes in miR-30b-5p were assessed by RT-PCR. Finally, the neuroprotective function of miR-30b-5p is measured by brain water content, mNSSs and beam-walking test. SEMA3A expression varied following TBI and peaked on the third day which expressed approximate fourfold increase compared with sham group, with the protein concentrated at the lesion boundary. SEMA3A contributed to neurological function deficits and secondary BBB damage in vivo. Our results demonstrated that SEMA3A level following OGD injury almost doubled than control group, and the negative effects of OGD injury can be improved by blocking SEMA3A expression. Furthermore, the expression of miR-30b-5p decreased approximate 40% at the third day and 60% at the seventh day post-CCI. OGD injury also exhibited an effect to approximately decrease 50% of miR-30b-5p expression. Additionally, the expression of SEMA3A post-TBI is regulated by miR-30b-5p, and miR-30b-5p could improve neurological outcomes post-TBI efficiently. Our results demonstrate that SEMA3A is a significant factor in secondary BBB damage after TBI and can be abolished by miR-30b-5p, which represents a potential therapeutic target.

10.
World Neurosurg ; 127: 354-361, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30995556

RESUMEN

OBJECTIVE: The purpose of this study was to evaluate the efficacy of surgical revascularization versus conservative treatment and different surgical modalities, in order to provide evidence for the patient with moyamoya disease (MMD) to choose the appropriate treatment. METHODS: We comprehensively searched PubMed, Embase, Web of Science, and the Cochrane Library for articles published regarding MMD treatment. If the I2 value, which evaluated the heterogeneity, was <50%, a fixed-effect model was used; if not, a random effect model was applied. RESULTS: Twenty-seven articles were included in the meta-analysis. The surgery group is more advantageous in reducing the risk of future stroke events than conservative treatment in MMD patients (odds ratio [OR] 0.26, 95% confidence interval [CI] 0.20-0.33, P < 0.001). In addition, the surgical group also had an advantage in terms of increased cerebral perfusion (OR 7.16, 95% CI 3.28-15.64, P < 0.001) and death due to rebleeding (OR 0.27, 95% CI 0.10-0.72, P < 0.01). Direct surgery showed a significant efficacy over indirect surgery (OR 2.03, 95% CI 1.32-3.13, P < 0.01). No obvious difference was found between the direct and indirect bypass subset (OR 0.76, 95% CI 0.51-1.14, P = 0.185). Angiographic results in patients undergoing direct bypass surgery are more pronounced (OR 0.20, 95% CI 0.06-0.67, P < 0.01). CONCLUSIONS: In patients with symptomatic moyamoya disease, bypass surgery is more effective than conservative treatment to prevent future strokes. In surgical patients, direct bypass seems to reduce the risk of stroke more than an indirect bypass.


Asunto(s)
Revascularización Cerebral/métodos , Enfermedad de Moyamoya/diagnóstico por imagen , Enfermedad de Moyamoya/cirugía , Revascularización Cerebral/tendencias , Humanos , Pronóstico , Estudios Prospectivos , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Estudios Retrospectivos , Resultado del Tratamiento
11.
Med Sci Monit ; 25: 928-936, 2019 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-30710072

RESUMEN

BACKGROUND Endothelial injury is the early pathological change of cerebral aneurysm (CA) formation. In addition to its lipid-lowering activity, atorvastatin (ATR) also reportedly promotes vascular repair via mobilizing endothelial progenitor cells (EPC). Here, we investigated the influence of ATR on vascular worsening after CA induction in rats. MATERIAL AND METHODS Adult male Sprague-Dawley rats were randomly assigned to 3 groups: a control (CTR) group, a CA group, and a CA+ATR treatment group. Circulating EPC level and hematological and lipid profiles were measured 3 months after CA induction. Verhoeff-Van Gieson staining and transmission electron microscopy were performed to assess pathological changes in the artery wall. RT-PCR was also performed to evaluate the expression of inflammation-related genes in the aneurysmal wall. RESULTS ATR significantly restored the impaired level of circulating EPC without changing hematological and lipid profiles 3 months after CA induction. ATR markedly inhibited endothelial injury, media thinning, and CA enlargement, accompanied by reduced vascular inflammation. CONCLUSIONS Our preliminary results demonstrate that the mobilization of EPC and improvement of endothelial function by ATR contribute to the prevention of cerebral aneurysm. Further studies are warranted to investigate the detailed mechanism.


Asunto(s)
Atorvastatina/metabolismo , Aneurisma Intracraneal/patología , Animales , Atorvastatina/farmacología , Movimiento Celular , Modelos Animales de Enfermedad , Células Progenitoras Endoteliales/efectos de los fármacos , Células Progenitoras Endoteliales/patología , Movilización de Célula Madre Hematopoyética/métodos , Aneurisma Intracraneal/tratamiento farmacológico , Aneurisma Intracraneal/prevención & control , Masculino , Sustancias Protectoras/metabolismo , Ratas , Ratas Sprague-Dawley
12.
Org Biomol Chem ; 17(11): 2883-2886, 2019 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-30793723

RESUMEN

New chiral thiosquaramides and their applications in catalytic asymmetric double addition of 5-methyl-2(3H)-furanones to nitroolefins were described. Enantiomerically enriched 2,4,4-trisubstituted butenolides bearing a quaternary stereogenic center could be smoothly constructed with high diastereoselectivities (up to >99 : 1 dr) and excellent enantioselectivities (up to 95% ee) under mild conditions.

13.
J Neurotrauma ; 36(8): 1291-1305, 2019 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-29695199

RESUMEN

Our recent articles have reported that increased miR-21-5p in brain after traumatic brain injury (TBI) could improve the neurological outcome through alleviating blood-brain barrier (BBB) damage. miR-21-3p is another mature miRNA derived from pre-miR-21 after Dicer Procession other than miR-21-5p. Its roles in various diseases, such as tumors and myocardial disease, aroused great interest for research in recent years. To further explore the function and underlying mechanism of miR-21, especially miR-21-3p, in regulating the pathological development of BBB damage after TBI, we designed this research and focused on studying the impact of miR-21-3p on apoptosis and inflammation in brain microvascular endothelial cells (BMVECs), the major cellular component of BBB. We performed controlled cortical impact on mouse brain and employed the oxygen glucose deprivation/reoxygenation (OGD)-treated bEnd.3 cells injury model. We found that the miR-21-3p level in BMVECs from injured cerebral cortex of controlled cortical impact (CCI) mice and bEnd.3 cells with OGD treatment were both increased after injury. For in vitro experiments, downregulation on the miR-21-3p level by transfecting miR-21-3p antagomir in cultured cells alleviated OGD-induced BBB damage, characterized by decreased BBB leakage and increased expression of tight junction proteins. Besides, miR-21-3p antagomir could suppress cell death by anti-apoptosis and control inflammatory response by inhibiting the activity of NF-κB signaling. Using luciferase reporter assay and a MAT2B-silenced shRNA vector, we further proved that miR-21-3p exerted the above functions through targeting MAT2B. In addition, in vivo experiments also confirmed that intracerebroventricular infusion of miR-21-3p antagomir could alleviate BBB leakage after TBI. It reduced Evans Blue extravasation and promoted the expression of tight junction proteins, thus contributed to improve the neurological outcome of CCI mice. Taken together, increased miR-21-3p in BMVECs after TBI was bad for restoration of injured BBB. Downregulation on the miR-21-3p level in injured brain could be a promising therapeutic strategy for BBB damage after TBI.


Asunto(s)
Barrera Hematoencefálica/patología , Lesiones Traumáticas del Encéfalo/patología , Células Endoteliales/patología , Metionina Adenosiltransferasa/metabolismo , MicroARNs/metabolismo , Animales , Apoptosis/fisiología , Barrera Hematoencefálica/metabolismo , Lesiones Traumáticas del Encéfalo/metabolismo , Células Endoteliales/metabolismo , Regulación de la Expresión Génica/fisiología , Inflamación/metabolismo , Inflamación/patología , Masculino , Ratones , Ratones Endogámicos C57BL
14.
Neural Regen Res ; 13(10): 1753-1758, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30136690

RESUMEN

Traumatic brain injury can cause loss of neuronal tissue, remote symptomatic epilepsy, and cognitive deficits. However, the mechanisms underlying the effects of traumatic brain injury are not yet clear. Hippocampal excitability is strongly correlated with cognitive dysfunction and remote symptomatic epilepsy. In this study, we examined the relationship between traumatic brain injury-induced neuronal loss and subsequent hippocampal regional excitability. We used hydraulic percussion to generate a rat model of traumatic brain injury. At 7 days after injury, the mean modified neurological severity score was 9.5, suggesting that the neurological function of the rats was remarkably impaired. Electrophysiology and immunocytochemical staining revealed increases in the slope of excitatory postsynaptic potentials and long-term depression (indicating weakened long-term inhibition), and the numbers of cholecystokinin and parvalbumin immunoreactive cells were clearly reduced in the rat hippocampal dentate gyrus. These results indicate that interneuronal loss and changes in excitability occurred in the hippocampal dentate gyrus. Thus, traumatic brain injury-induced loss of interneurons appears to be associated with reduced long-term depression in the hippocampal dentate gyrus.

15.
Med Sci Monit ; 24: 5292-5300, 2018 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-30059491

RESUMEN

BACKGROUND Osteoprotegerin (OPG) inhibits bone resorption and binds with strong affinity to receptor activator of NF κB ligand (RANKL), thereby preventing RANKL from binding to its receptor RANK. Osteoclasts have documented effects on bone erosion of rheumatoid arthritis (RA). The aim of this study was to examine the role of miR-145-5p in the regulation of RA osteoclast differentiation and bone erosion. MATERIAL AND METHODS Expression of microRNA-145-5p in human peripheral blood mononuclear cells (PBMC) and synovial tissue was assayed by real-time polymerase chain reaction (RT-PCR). OPG, RANK, and RANKL expression in RAW-264.7 cells was examined by RT-PCR and Western blot analysis. Osteoclast formation was detected by tartrate-resistant acid phosphatase (TRAP) staining. The effect of miR-145-5p on predicted target mRNAs was examined by luciferase reporter assays. Collagen-induced arthritis (CIA) was induced by injecting DBA/1 mice with bovine type II collagen (CII), and miR-145-5p agomir was administered by intravenous injection. Morphological changes in the CIA joint were assessed by micro-computed tomography (CT) and histopathology. RESULTS miR-145-5p levels significantly increased in RA PBMC and synovial tissue compared with normal PBMC and osteoarthritis (OA) tissue. After transfection of RAW-264.7 cells with miR-145-5p, RANK and RANKL expression increased significantly, while OPG expression decreased significantly. TRAP staining results showed osteoclast numbers increased. Micro-CT analysis of the arthritic joints showed that the miR-145-5p agomir caused bone erosion in mice, and histopathological analysis revealed that miR-145-5p agomir aggravates cartilage erosion. CONCLUSIONS Our findings indicate that administration of miR-145-5p aggravates joint erosion in CIA mice. This suggests that miR-145-5p is a potential target for the treatment of RA.


Asunto(s)
Artritis Experimental/genética , Resorción Ósea/genética , MicroARNs/biosíntesis , Osteoclastos/patología , Osteoprotegerina/biosíntesis , Adulto , Animales , Artritis Experimental/metabolismo , Artritis Experimental/patología , Artritis Reumatoide/genética , Artritis Reumatoide/metabolismo , Artritis Reumatoide/patología , Resorción Ósea/patología , Bovinos , Colágeno Tipo II/administración & dosificación , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos DBA , MicroARNs/administración & dosificación , MicroARNs/sangre , MicroARNs/genética , MicroARNs/metabolismo , Persona de Mediana Edad , Osteoclastos/metabolismo , Osteoprotegerina/genética , Osteoprotegerina/metabolismo , Ligando RANK/biosíntesis , Ligando RANK/metabolismo , Células RAW 264.7 , Receptor Activador del Factor Nuclear kappa-B/biosíntesis , Receptor Activador del Factor Nuclear kappa-B/metabolismo , Membrana Sinovial/metabolismo , Membrana Sinovial/patología , Transfección , Adulto Joven
16.
Chirality ; 30(9): 1096-1104, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30052289

RESUMEN

Cinchona alkaloid-derived 4-methyl/nitro benzoylthioureas were synthesized, which smoothly catalyzed the asymmetric Michael addition of pyrazolin-5-ones to nitroolefins. The results showed that electronic effects of substituents in the benzene ring of benzoylthioureas have subtle influences on their catalytic abilities and electron donating methyl group is favored than electron withdrawing nitro group. Preliminary Hartree-Fock calculations revealed that in the catalytic cycle, hydrogen bond energies of the complex formed with 4-methylbenzoylthioureas are about 0.19 to 1.56 kcal/mol higher than with the corresponding 4-nitrobenzoylthioureas. 4-Methylbenzoylthioureas were identified as the most effective catalysts that promoted asymmetric Michael addition of pyrazolin-5-ones to nitroolefins to give the S- or R-products with high enantioselectivities.

17.
Neurobiol Dis ; 117: 15-27, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29859317

RESUMEN

The nucleotide-binding oligomerization domain (NOD)-like receptor family pyrin domain containing 3 (NLRP3) inflammasome-mediated inflammatory response has emerged as a prominent contributor to the pathophysiological processes of traumatic brain injury (TBI). Recently, a potent, selective, small-molecule NLRP3 inflammasome inhibitor, MCC950, was described. Here, we investigated the effect of MCC950 on inflammatory brain injury and long-term neurological outcomes in a mouse model of TBI. Male C57/BL6 mice were subjected to TBI using the controlled cortical impact injury (CCI) system. Western blotting, flow cytometry, and immunofluorescence assays were utilized to analyze post-traumatic NLRP3 inflammasome expression and determine its cellular source. We found that NLRP3 inflammasome expression was significantly increased in the peri-contusional cortex and that microglia were the primary source of this expression. The effects of MCC950 on mice with TBI were then determined using post-assessments including analyses of neurological deficits, brain water content, traumatic lesion volume, neuroinflammation, blood-brain barrier (BBB) integrity, and cell death. MCC950 treatment resulted in a better neurological outcome after TBI by alleviating brain edema, reducing lesion volume, and improving long-term motor and cognitive functions. The therapeutic window for MCC950 against TBI was as long as 6 h. Furthermore, the neuroprotective effect of MCC950 was associated with reduced microglial activation, leukocyte recruitment, and pro-inflammatory cytokine production. In addition, MCC950 preserved BBB integrity, alleviated TBI-induced loss of tight junction proteins, and attenuated cell death. Notably, the efficacy of MCC950 was abolished in microglia-depleted mice. These results indicate that microglia-derived NLRP3 inflammasome may be primarily involved in the inflammatory response to TBI, and specific NLRP3 inflammasome inhibition using MCC950 may be a promising therapeutic approach for patients with TBI.


Asunto(s)
Lesiones Traumáticas del Encéfalo/tratamiento farmacológico , Lesiones Traumáticas del Encéfalo/metabolismo , Compuestos Heterocíclicos de 4 o más Anillos/uso terapéutico , Proteína con Dominio Pirina 3 de la Familia NLR/antagonistas & inhibidores , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Sulfonas/uso terapéutico , Animales , Modelos Animales de Enfermedad , Furanos , Compuestos Heterocíclicos de 4 o más Anillos/farmacología , Indenos , Inflamasomas/antagonistas & inhibidores , Inflamasomas/biosíntesis , Inflamasomas/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Distribución Aleatoria , Sulfonamidas , Sulfonas/farmacología , Factores de Tiempo , Resultado del Tratamiento
18.
Brain Res ; 1694: 104-110, 2018 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-29777675

RESUMEN

Microparticles are cell fragments derived from damaged cells that are able to present an antigen from the parent cells to other cells to activate intracellular signaling pathways. Microparticles are closely related to the inflammatory response. Brain-derived microparticles (BDMPs) play an important role in brain injury. However, the inflammatory effect of BDMPs on microglia/macrophages remains unclear. The BDMPs were consumed by microglia/macrophages in vivo and in vitro. The BDMPs activated microglia/macrophages and changed their morphology in vitro. The BDMPs dysregulate the production of pro-inflammatory factors, suggesting that the effect of the BDMPs on microglia/macrophages is pro-inflammatory. In this study, we used flow cytometry, hopping probe ion conductance microscopy, immunofluorescence and other techniques to study the effect of brain-derived microparticle activation on microglia/macrophages that leads to neuroinflammation. BDMPs might be possible targets for the treatment of traumatic brain injury (TBI) changes after secondary nerve inflammation.


Asunto(s)
Encéfalo/metabolismo , Micropartículas Derivadas de Células/metabolismo , Inflamación/metabolismo , Macrófagos/metabolismo , Microglía/metabolismo , Animales , Lesiones Encefálicas/metabolismo , Lesiones Traumáticas del Encéfalo/metabolismo , Modelos Animales de Enfermedad , Masculino , Ratones Endogámicos C57BL
19.
Front Cell Neurosci ; 11: 193, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28729823

RESUMEN

Traumatic brain injury (TBI) is one of the leading causes of trauma-induced mortality and disability, and emerging studies have shown that endoplasmic reticulum (ER) stress plays an important role in the pathophysiology of TBI. Tauroursodeoxycholic acid (TUDCA), a hydrophilic bile acid, has been reported to act as an ER stress inhibitor and chemical chaperone and to have the potential to attenuate apoptosis and inflammation. To study the effects of TUDCA on brain injury, we subjected mice to TBI with a controlled cortical impact (CCI) device. Using western blotting, we first examined TBI-induced changes in the expression levels of GRP78, an ER stress marker, p-PERK, PERK, p-eIF2a, eIF2a, ATF4, p-Akt, Akt, Pten, Bax, Bcl-2, Caspase-12 and CHOP, as well as changes in the mRNA levels of Akt, GRP78, Caspase-12 and CHOP using RT-PCR. Neuronal cell death was assessed by a terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end-labeling (TUNEL) assay, and CHOP expression in neuronal cells was detected by double-immunofluorescence staining. Neurological and motor deficits were assessed by modified neurological severity scores (mNSS) and beam balance and beam walking tests, and brain water content was also assessed. Our results indicated that ER stress peaked at 72 h after TBI and that TUDCA abolished ER stress and inhibited p-PERK, p-eIF2a, ATF4, Pten, Caspase-12 and CHOP expression levels. Moreover, our results show that TUDCA also improved neurological function and alleviated brain oedema. Additionally, TUDCA increased p-Akt expression and the Bcl-2/Bax ratio. However, the administration of the Akt inhibitor MK2206 or siRNA targeting of Akt abolished the beneficial effects of TUDCA. Taken together, our results indicate that TUDCA may attenuate early brain injury via Akt pathway activation.

20.
Chirality ; 28(11): 721-727, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27791318

RESUMEN

Organocatalysis and aqueous reactions are identified as the focus of the greening of chemistry. Combining these two strategies effectively remains an interesting challenge in organic synthesis. Herein, we used pyrrolidine-based benzoylthiourea 1c to catalyze the asymmetric Michael addition of cyclohexanone to various nitroolefins in water to afford the corresponding compounds in moderate to good yields, and with excellent diastereoselectivities (up to >99:1 dr) and enantioselectivities (up to 99% ee).

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...