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Tumor necrosis factor alpha (TNF-α) is an essential cytokine that mediates cell death and has been shown to play a potential role in inducing neural stem cell (NSC) apoptosis. We have previously shown that TNF-α antagonist etanercept can suppress the transplanted NSC apoptosis induced by TNF-α in spinal cord injury (SCI) sites; however, the precise molecular mechanism remains unclear. This study aimed to investigate the signaling pathways responsible for TNF-α-induced apoptosis in NSCs. TNF-α treatment impairs cell viability and increases apoptosis of NSCs in concentration- and time-dependent manners. This is embodied in an increase in Bax and cleaved caspase-3 production, coupled with decreased Bcl-2 levels. Additionally, TNF-α remarkably increased the expression of phosphatidylinositol p38 Mitogen-activated protein kinase (p38 MAPK) in NSCs. p38 MAPK regulates apoptosis, acting as an apoptotic signal due to TNF-α exposure. TNF-α-induced apoptosis was significantly alleviated by the p38 MAPK pathway inhibitor SB203580, as well as targeted inhibition of p38 gene in NSCs, or TNF-α antagonist etanercept. These results suggest that TNF-α induces NSCs apoptosis by activating the p38 MAPK signaling pathway and etanercept acts as an effective TNF-α antagonist to prevent p38 MAPK-dependent apoptosis induced by TNF-α in NSCs. Our research represents a potential gene targeting that can prevent unnecessary grafted cell death after transplantation into the SCI models.
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Apoptosis/efectos de los fármacos , Células-Madre Neurales/efectos de los fármacos , Factor de Necrosis Tumoral alfa/farmacología , Animales , Caspasa 3/metabolismo , Imidazoles/farmacología , Sistema de Señalización de MAP Quinasas , Piridinas/farmacología , Ratas , Factor de Necrosis Tumoral alfa/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismoRESUMEN
After spinal cord injury, the concentrations of total and hyperphosphorylated tau in cerebrospinal fluid increase, and levels of both correlate with injury severity. Tau inhibition is considered effective therapy for many central nervous system diseases, including traumatic brain injury and Alzheimer's disease. However, whether it can play a role in the treatment of spinal cord injury remains unclear. In this study, the therapeutic effects of tau inhibition were investigated in a rat model of transection spinal cord injury by injecting the rats with a lentivirus encoding tau siRNA that inhibits tau expression. We found that tau inhibition after spinal cord injury down-regulated the levels of inflammatory mediators, including tumor necrosis factor-α, interleukin-6 and interleukin-1ß. It also led to a shift of activated microglial polarization from the M1 pro-inflammatory phenotype to the M2 anti-inflammatory phenotype, and reduced the amount of reactive oxygen species in the acute phase. Furthermore, the survival of residual neural cells around the injury epicenter, and neuronal and axonal regeneration were also markedly enhanced, which promoted locomotor recovery in the model rats. Collectively, our findings support the conclusion that tau inhibition can attenuate neuroinflammation, alleviate oxidative stress, protect residual cells, facilitate neurogenesis, and improve the functional recovery after spinal cord injury, and thus suggest that tau could be a good molecular target for spinal cord injury therapy.
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GSK-3ß (glycogen synthase kinase-3ß), a crucial tau kinase, negatively regulates PP2A (protein phosphatase 2A), the most active tau phosphatase that is suppressed in the brain in AD (Alzheimer's disease). However, the molecular mechanism is not understood. In the present study we found that activation of GSK-3ß stimulates the inhibitory phosphorylation of PP2A at Tyr307 (pY307-PP2A), whereas inhibition of GSK-3ß decreased the level of pY307-PP2A both in vitro and in vivo. GSK-3ß is a serine/threonine kinase that can not phosphorylate tyrosine directly, therefore we measured PTP1B (protein tyrosine phosphatase 1B) and Src (a tyrosine kinase) activities. We found that GSK-3ß can modulate both PTP1B and Src protein levels, but it only inhibits PTP1B activity, with no effect on Src. Furthermore, only knockdown of PTP1B but not Src by siRNA (small interfering RNA) eliminates the effects of GSK-3ß on PP2A. GSK-3ß phosphorylates PTP1B at serine residues, and activation of GSK-3ß reduces the mRNA level of PTP1B. Additionally, we also observed that GSK-3 negatively regulates the protein and mRNA levels of PP2A, and knockdown of CREB (cAMP-response-element-binding protein) abolishes the increase in PP2A induced by GSK-3 inhibition. The results of the present study suggest that GSK-3ß inhibits PP2A by increasing the inhibitory Tyr307 phosphorylation and decreasing the expression of PP2A, and the mechanism involves inhibition of PTP1B and CREB.
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Glucógeno Sintasa Quinasa 3/fisiología , Proteína Fosfatasa 2/metabolismo , Proteína Tirosina Fosfatasa no Receptora Tipo 1/metabolismo , Familia-src Quinasas/metabolismo , Androstadienos/farmacología , Animales , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Glucógeno Sintasa Quinasa 3 beta , Células HEK293 , Humanos , Indoles/farmacología , Maleimidas/farmacología , Ratones , Ratones Endogámicos C57BL , ARN Mensajero/metabolismo , Ratas , Serina/metabolismo , Transcripción Genética/efectos de los fármacos , Tirosina/metabolismo , Wortmanina , Proteínas tau/metabolismoRESUMEN
A novel twofold interpenetrating two-dimensional (2D) ZnII coordination framework, poly[[(µ-1,3-bis(2-methyl-1H-imidazol-1-yl)benzene-κ2N3:N3)(µ-naphthalene-2,6-dicarboxylato-κ2O2:O6)zinc(II)] dimethylformamide monosolvate], {[Zn(C12H6O4)(C14H14N4)]·C3H7NO}n or {[Zn(1,3-BMIB)(NDC)]·DMF}n (I), where H2NDC is naphthalene-2,6-dicarboxylic acid, 1,3-BMIB is 1,3-bis(2-methyl-1H-imidazol-1-yl)benzene and DMF is dimethylformamide, was prepared and characterized through IR spectroscopy, elemental analysis, thermal analysis and single-crystal X-ray diffraction. Single-crystal X-ray diffraction analysis revealed that (I) exhibits an unusual twofold interpenetrating 2D network. In addition, it displays strong fluorescence emissions and a high photocatalytic activity for the degradation of Rhodamine B (RhB) under UV-light irradiation.
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OBJECTIVE: This study aimed to determine the effects of the long non-coding (lnc) RNA MT1JP on the apoptosis and migration of hepatocellular carcinoma cells. PATIENTS AND METHODS: Patients with liver cancer admitted to the Second People's Hospital of Liaocheng were included in this study. We transfected hepatocellular carcinoma cells with MT1JP and miR-24-3p and assessed their expression and effects on apoptosis and migration. Correlations were verified using a dual-luciferase reporter and RNA-binding protein coimmunoprecipitation. RESULTS: The expression of MT1JP was downregulated (P < 0.05), whereas that of miR-24-3p was upregulated in liver cancer. Serum MT1JP levels were correlated with tumor size, alpha-fetoprotein (AFP), TNM stage, differentiation, and lymph node metastasis. Both MT1JP overexpression and miR-24-3p inhibition inhibited cellular proliferation and migration and increased apoptosis rates. They significantly downregulated expression of the cell migration-associated proteins matrix metalloproteinase -2, -9 (MMP-2, MMP-9) (P < 0.05). They upregulated the expression of Bcl-2-related X protein (Bax) and cysteinyl aspartate-specific proteinases (Caspase-3 and -9) proteins that are involved in apoptosis. They decreased expression of B-cell lymphoma/leukemia-2 (Bcl-2; P < 0.05). A target relationship between MT1JP and miR-24-3p was identified using dual-luciferase gene reporter assays and RNA-binding protein coimmunoprecipitations. MT1JP overexpression significantly downregulated miR-24-3p expression (P < 0.05). MT1JP and miR-24-3p expression were negatively correlated in liver cancer tissues (r = -0.561, P < 0.001; Pearson χ2 tests). Rescue experiments showed that upregulating miR-24-3p expression could counteract MT1JP overexpression in hepatocellular carcinoma cells. CONCLUSION: MT1JP, even when expressed at low levels, participates in the proliferation, apoptosis, and migration of liver cancer cells by regulating miR-24-3p.
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AIM: To describe the complex, overlapping phenotype of four Chinese patients with inherited retinal dystrophies (IRDs) who harbored two pathogenic genes simultaneously. METHODS: This retrospective study included 4 patients affected with IRDs. Medical and ophthalmic histories were obtained, and clinical examinations were performed. A specific Hereditary Eye Disease Enrichment Panel (HEDEP) based on exome capture technology was used for genetic screening. RESULTS: Four patients were identified to harbor disease-causing variants in two different genes. Patient retinitis pigmentosa (RP) 01-II:1 exhibited both classical ABCA4-induced Stargardt disease (STGD) 1 and USH2A-associated RP, patient RP02-III:2 exhibited both classical ABCA4-induced STGD1 and CDH23-associated RP, patient RP03-II:1 exhibited both USH2A-induced autosomal recessive retinitis pigmentosa (arRP) syndrome and SNRNP200-induced autosomal dominant retinitis pigmentosa (adRP), and patient RP04-II:2 exhibited USH2A-induced arRP syndrome and EYS-induced arRP at the same time. CONCLUSION: Our study demonstrates that genotype-phenotype correlations and comprehensive genetic screening is crucial for diagnosing IRDs and helping family planning for patients suffering from the disease.
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A novel two-dimensional (2D) ZnII coordination framework, poly[[µ-1,3-bis(2-methyl-1H-imidazol-1-yl)benzene](µ-5-nitrobenzene-1,3-dicarboxylato)zinc(II)], [Zn(C8H3NO6)(C14H14N4)]n or [Zn(NO2-BDC)(1,3-BMIB)]n [1,3-BMIB is 1,3-bis(2-methyl-1H-imidazol-1-yl)benzene and NO2-H2BDC is 5-nitrobenzene-1,3-dicarboxylic acid], has been prepared and characterized by IR, elemental analysis, thermal analysis and single-crystal X-ray diffraction. Single-crystal X-ray diffraction analysis revealed that the compound is a new 2D polymer with a 63 topology parallel to the (10-2) crystal planes based on left-handed helices, right-handed helical NO2-BDC-Zn chains and [Zn2(1,3-BMIB)2]n clusters. In the crystal, adjacent layers are further connected by C-H...O hydrogen bonds, C-H...π interactions, C-O...π interactions and N-O...π interactions to form a three-dimensional structure in the solid state. In addition, the compound exhibits strong fluorescence emissions in the solid state at room temperature.
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A novel two-dimensional CoII coordination framework, namely poly[(µ2-biphenyl-4,4'-diyldicarboxylato-κ2O4:O4'){µ2-bis[4-(2-methyl-1H-imidazol-1-yl)phenyl] ether-κ2N3:N3'}cobalt(II)], [Co(C14H8O4)(C20H18N4O)]n, has been prepared and characterized by IR, elemental analysis, thermal analysis and single-crystal X-ray diffraction. The crystal structure reveals that the compound has an achiral two-dimensional layered structure based on opposite-handed helical chains. In addition, it exhibits significant photocatalytic degradation activity for the degradation of methylene blue.
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A novel two-dimensional CdII coordination framework, poly[[[µ-1,3-bis(2-methyl-1H-imidazol-1-yl)benzene-κ2N:N'](µ-1,3-phenylenediacetato-κ4O,O':O'',O''')cadmium(II)] dihydrate], {[Cd(C10H8O4)(C14H14N4)]·2H2O}n or {[Cd(PDA)(1,3-BMIB)]·2H2O}n [1,3-BMIB is 1,3-bis(2-methyl-1H-imidazol-1-yl)benzene and H2PDA is 1,3-phenylenediacetic acid], has been prepared and characterized using IR, elemental analysis, thermal analysis and single-crystal X-ray diffraction, the latter revealing that the compound is a (4,4) grid coordination polymer with layers oriented parallel to the bc crystal planes. In the crystal, adjacent layers are further connected by O-H...O and C-H...O hydrogen bonds, forming a three-dimensional structure in the solid state. In addition, the compound exhibits strong fluorescence emissions and shows photocatalytic activity for the degradation of methylene blue in the solid state at room temperature.
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OBJECTIVE: To evaluate the efficacy of ropivacaine injection at the acupoints Hegu and Sanyinjiao for labor analgesia and its effects on cortisol level in parturients. METHODS: A total of 120 ASA class I-II nulliparous women undergoing spontaneous term labor (37 to 41 weeks of gestation) with a live, singleton fetus in the occiput anterior position and requiring labor analgesia with acupuncture were enrolled in this study. These women were randomized into study group and control group and received injections of 1 mL of 0.2% ropivacaine and normal saline, respectively, at each of the acupoints of bilateral Sanyinjiao and Hegu in the first stage of labor. The Visual Analogue Scale (VAS) before and at 30, 60 and 120 min after analgesia, the time of labor, delivery outcome and cortisol levels were compared between the two groups. RESULTS: The VAS was significantly lower in the study group than in the control group (P<0.05). At 120 min after injections of ropivacaine or saline, serum cortisol level was significantly higher in the control group than in the study group (P<0.05). The rates of cesarean section and instrumental delivery and the time of labor were all similar between the two groups (P>0.05). CONCLUSION: Ropivacaine injection at Hegu and Sanyinjiao is effective for labor analgesia and does not prolong the process of labor or increase the rates of cesarean section or instrumental delivery.
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Puntos de Acupuntura , Analgesia Obstétrica , Anestésicos Locales/administración & dosificación , Hidrocortisona/sangre , Ropivacaína/administración & dosificación , Cesárea/estadística & datos numéricos , Femenino , Humanos , EmbarazoRESUMEN
In 2007-2014, a position experiment was conducted in the Weibei Highlands Region to study effects of long-term straw mulching on spring maize planted on rain fed farmlands with diffe-rent conservative tillage practice patterns, no tillage plus sub-soiling (NT/ST), sub-soiling plus deep plowing (ST/CT), deep plowing plus no tillage (CT/NT), only no tillage (NT), only sub-soiling (ST) and only deep plowing (CT), by measuring and analyzing organic carbon and nitrogen storage in 0-60 cm soil and dynamic moistures in 0-200 cm soil at the maize harvesting time as well as the yields of maize. The results showed that the soil organic carbon storage and soil nitrogen storage increased most with the NT/ST among the six conservative tillage practice patterns. Compared with the experiment results before 2007, the organic carbon storage in 0-60 cm soil increased under the six conservative tillage practice patterns and their five-year averagely increase reached 12.3%-28.3%. Compared with the organic carbon and nitrogen storage with the CT, the five-year soil organic carbon storage under the other conservative tillage practice patterns increased by 7.1%-13.2%. The five-year nitrogen storage in 0-60 cm soil under NT/ST, ST/CT and CT/NT as well as NT increased by 2.5%-7.3% compared with the corresponding soil nitrogen storage before the start of experiment. The five-year average nitrogen storage under NT/ST, ST/CT, CT/NT, NT and ST increased by 3.6%-11.1% compared with that under CT. Compared with the soil moisture under CT, the soil moistures under the other five conservative tillage patterns separately increased by 5.7%, 2.3%, 2.0%, 5.5% and 4.4%, and the soil moisture under NT/ST was the highest. The average yields of spring maize ranked in order of NT/ST>ST/CT>ST>NT>CT/NT>CT and the yield of spring maize under NT/ST was the highest and separately increased by 4.2%,13.0%,11.3%,4.7% and 13.8% compared with those under the other five conservative tillage patterns, and the average economic returns were in order of NT/ST>ST/CT>ST>NT>CT/NT>CT. Among the six conservative tillage patterns, NT/ST performed better in improving soil environment quality, soil fertility and increasing maize yield and return, so it was a conservative tillage pattern more suitable for croplands for spring maize.
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Agricultura/métodos , Carbono/análisis , Nitrógeno/análisis , Suelo/química , Zea mays/crecimiento & desarrollo , China , Productos Agrícolas/crecimiento & desarrollo , Lluvia , Estaciones del AñoRESUMEN
BACKGROUND: Diabetes mellitus (DM) remains a major health problem worldwide. Several clinical trials have shown the superiority of the Traditional Chinese Medicine in delaying or reversing the development and progression of DM. This study aimed to evaluate the efficacy of Jinlida (JLD) granule, a Chinese herbal recipe, in the treatment of impaired glucose tolerance (IGT) and its effect on the prevention of DM. METHODS: Sixty-five IGT patients were randomized to receive one bag of JLD granules three times daily (JLD group, n = 34) or no drug intervention (control group, n = 31) for 12 weeks. Oral glucose tolerance test, glycated hemoglobin A1c (HbA1c), body mass index, blood lipids levels, fasting insulin, and insulin resistance calculated using homeostatic model assessment (HOMA-IR) of all the patients were observed and compared before and after the treatment. RESULTS: Sixty-one participants completed the trial (32 in JLD group and 29 in the control group). There were statistically significant decreases in HbA1c (P < 0.001), 2-h plasma glucose (P < 0.001), and HOMA-IR (P = 0.029) in JLD group compared with the control group after 12 weeks of treatment. After 12 weeks of treatment, two (6.9%) patients returned to normal blood glucose, and five (17.2%) patients turned into DM in control group, while in the JLD group, 14 (43.8%) returned to normal blood glucose and 2 (6.2%) turned into DM. There was a significant difference in the number of subjects who had normal glucose at the end of the study between two groups (P = 0.001). CONCLUSIONS: JLD granule effectively improved glucose control, increased the conversion of IGT to normal glucose, and improved the insulin resistance in patients with IGT. This Chinese herbal medicine may have a clinical value for IGT.
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Medicamentos Herbarios Chinos/uso terapéutico , Intolerancia a la Glucosa/tratamiento farmacológico , Adulto , Glucemia/efectos de los fármacos , Índice de Masa Corporal , Femenino , Intolerancia a la Glucosa/sangre , Prueba de Tolerancia a la Glucosa , Hemoglobina Glucada/metabolismo , Humanos , Hipoglucemiantes/uso terapéutico , Insulina/sangre , Resistencia a la Insulina , Masculino , Persona de Mediana EdadRESUMEN
Neural stem cell (NSC) transplantation has been reported to be a leading strategy to stimulate neuroplasticity, repair neuronal loss and promote the morphologic and functional recovery of spinal cord injury (SCI). However, massive death of transplanted NSCs is still a problem, which is considered to be related to a series of pro-inflammatory cytokines that induce apoptosis, extensive demyelination and axonal destruction. Tumor necrosis factor alpha (TNF-α), as one of the major inflammation initiators, contributes to secondary neural cell death. We previously found that the administration of the TNF-α antagonist etanercept during the acute phase of SCI can reduce the apoptosis of neurons and oligodendrocytes. To investigate whether etanercept can suppress transplanted NSC apoptosis and promote NSC survival, axon myelination and functional recovery, we tested the combination strategy of the early administration of etanercept and NSC transplantation. First we observed that etanercept suppressed the TNF-α expression and apoptosis of transplanted NSCs by Western blot, TUNEL and immunofluorescence staining. The Basso, Beattle and Bresnahan scale and motor-evoked potential were used to evaluate functional recovery. The results suggest significantly better recovery after combination therapy. Further, histopathological alterations were evaluated by hematoxylin and eosin staining and Nissl staining. These procedures showed that the early administration of etanercept improved survival of neurons in the ventral horn, restored neural morphology and produced a smaller cavity area. We observed most abundant NF-positive fibers after the combination treatment, indicating that combination therapy retained and promoted neural regeneration. Finally, the early suppression of TNF-α reduced the occurrence of demyelination, and the combination therapy led to more myelinated axons, as shown by electron microscopy. These data suggest that this strategy significantly protected transplanted NSCs via the anti-inflammation and anti-apoptosis effects of etanercept, promoting re-myelination, neural regeneration and locomotor function.
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Inmunoglobulina G/uso terapéutico , Regeneración Nerviosa , Células-Madre Neurales/trasplante , Fármacos Neuroprotectores/uso terapéutico , Receptores del Factor de Necrosis Tumoral/uso terapéutico , Traumatismos de la Médula Espinal/tratamiento farmacológico , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Animales , Apoptosis , Supervivencia Celular , Quimioterapia Combinada , Etanercept , Potenciales Evocados Motores , Femenino , Inmunoglobulina G/administración & dosificación , Actividad Motora/efectos de los fármacos , Fibras Nerviosas Mielínicas/efectos de los fármacos , Fibras Nerviosas Mielínicas/patología , Células-Madre Neurales/efectos de los fármacos , Células-Madre Neurales/fisiología , Fármacos Neuroprotectores/administración & dosificación , Ratas , Ratas Sprague-Dawley , Receptores del Factor de Necrosis Tumoral/administración & dosificación , Traumatismos de la Médula Espinal/metabolismo , Traumatismos de la Médula Espinal/fisiopatología , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
One approach for improving BCG efficacy is to utilize BCG as vehicle to develop recombinant BCG (rBCG) strains overexpressing Mycobacterium tuberculosis (M. tb) antigens. Also expression level of a candidate antigen should impact the final T cell responses conferred by rBCG. In this study, based on our previously constructed differential expression system, we developed two rBCG strains overexpressing M. tb chimeric antigen Ag856A2 (coding a recombinant ag85a with 2 copies of esat-6 inserted at Acc I site of ag85a) at differential levels under the control of the subtly modified furA promoters. These two rBCG strains were used to vaccinate C57BL/6 mice and exploit dose of incorporated antigen in rBCG to optimize immune response and protective efficiency against M. tb challenge in mouse model. The results showed that rBCG strains overexpressing Ag856A2 at differential levels induced different antigen-specific IFN-γ production and comparable number of M. tb-specific CD4 T cells expressing IL-2. M. tb challenge experiment showed that rBCG strains afforded enhanced but comparable immune protection characterized by reduced bacillary load, lung pathology, and inflammation. These results suggested that the dose of antigens incorporated in rBCG can impact T cell immune responses but imposed no significantly differential protective efficacies.
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Antígenos Bacterianos/inmunología , Epítopos Inmunodominantes/inmunología , Mycobacterium bovis/inmunología , Mycobacterium tuberculosis/inmunología , Células TH1/inmunología , Tuberculosis/prevención & control , Animales , Antígenos Bacterianos/genética , Vacuna BCG/genética , Vacuna BCG/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Modelos Animales de Enfermedad , Epítopos de Linfocito T/inmunología , Femenino , Inmunización , Interferón gamma/metabolismo , Interleucina-2/biosíntesis , Pulmón/inmunología , Pulmón/metabolismo , Pulmón/patología , Ratones , Mycobacterium bovis/genética , Óxido Nítrico Sintasa de Tipo II/metabolismo , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/inmunología , Tuberculosis/metabolismo , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
The intracellular accumulation of hyperphosphorylated tau plays a crucial role in neurodegeneration of Alzheimer's disease (AD), but the mechanism is not fully understood. From the observation that tau hyperphosphorylation renders cells more resistant to chemically-induced cell apoptosis, we have proposed that tau-involved apoptotic abortion may be the trigger of neurodegeneration. Here, we further studied whether this phenomenon is also applicable for the cell death induced by constitutively expressed factors, such as death-associated protein kinase 1 (DAPK1). We found that DAPK1 was upregulated and accumulated in the brain of human tau transgenic mice. Overexpression of DAPK1 in HEK293 and N2a cells decreased cell viability with activation of caspase-3, whereas simultaneous expression of tau antagonized DAPK1-induced apoptotic cell death. Expression of DAPK1 induced tau hyperphosphorylation at Thr231, Ser262, and Ser396 with no effects on protein phosphatase 2A, glycogen synthase kinase-3ß, protein kinase A, calcium/calmodulin dependent protein kinase II, cell division cycle 2, or cyclin dependent protein kinase 5. The phosphorylation level of microtubule affinity-regulating kinase 2 (MARK2) was increased by expression of DAPK1, but simultaneous downregulation of MARK2 did not affect the DAPK1-induced tau hyperphosphorylation. DAPK1 was co-immunoprecipitated with tau proteins both in vivo and in vitro, and expression of the kinase domain-truncated DAPK1 did not induce tau hyperphosphorylation. These data suggest that tau hyperphosphorylation at Thr231, Ser262, and Ser396 by DAPK1 renders the cells more resistant to the kinase-induced apoptotic cell death, providing new insights into the tau-involved apoptotic abortion in the course of chronic neurodegeneration.
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Apoptosis/fisiología , Proteínas Quinasas Asociadas a Muerte Celular/antagonistas & inhibidores , Proteínas Quinasas Asociadas a Muerte Celular/fisiología , Proteínas tau/metabolismo , Animales , Encéfalo/enzimología , Encéfalo/metabolismo , Encéfalo/patología , Línea Celular Tumoral , Proteínas Quinasas Asociadas a Muerte Celular/biosíntesis , Células HEK293 , Humanos , Ratones , Ratones Transgénicos , Fosforilación/fisiología , Regulación hacia Arriba/genética , Proteínas tau/análisisRESUMEN
Pesticides are widely used in agriculture, and epidemiological studies suggest that pesticide exposure is a risk factor for Alzheimer's disease (AD), but the mechanisms are elusive. Here, we studied the effects of pesticide exposure on the cognitive ability and the underlying mechanisms in rats. Deltamethrin and carbofuran were administered respectively into the rats once a day for 28 days by gavage. We found that pesticide exposure induced spatial learning and memory deficits with a simultaneous decrease of N-methyl-D-aspartate receptor 1, synaptophysin, and synapsin I, all of which are memory-related synaptic proteins. Pesticide exposure also induced tau hyperphosphorylation at multiple AD-related phosphorylation sites with activation of glycogen synthase kinase-3ß and inhibition of protein phosphatase-2A. Additionally, neuron loss in the hippocampus and cortex was observed upon administration of the pesticides. These results indicate that the pesticides exposure could induce AD-like pathology and cognitive abnormality in rats.