RESUMEN
BNIP3 is found to eliminate cancer cells via causing mitochondrial damage and endoplasmic reticulum stress, but it remains elusive of its role in regulating DNA double strand breaks (DSBs). In this study, we find that silibinin triggers DNA DSBs, ROS accumulation and expressional upregulation of BNIP3 in glioma cells. Mitigation of ROS with antioxidant GSH significantly inhibits silibinin-induced DNA DSBs and glioma cell death. Then, we find knockdown of BNIP3 with SiRNA obviously prevents silibinin-induced DNA DSBs and ROS accumulation. Mechanistically, BNIP3 knockdown not only reverses silibinin-triggered depletion of cysteine and GSH via maintaining xCT level, but also abrogates catalase decrease. Notably, silibinin-induced dephosphorylation of mTOR is also prevented when BNIP3 is knocked down. Given that activated mTOR could promote xCT expression and inhibit autophagic degradation of catalase, our data suggest that BNIP3 contributes to silibinin-induced DNA DSBs via improving intracellular ROS by inhibition of mTOR.
Asunto(s)
Roturas del ADN de Doble Cadena , Glioma/metabolismo , Glioma/patología , Proteínas de la Membrana/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Silibina/farmacología , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Sistema de Transporte de Aminoácidos y+/metabolismo , Catalasa/metabolismo , Línea Celular Tumoral , Cisteína/metabolismo , Roturas del ADN de Doble Cadena/efectos de los fármacos , Regulación hacia Abajo/efectos de los fármacos , Glutatión/metabolismo , Humanos , Especies Reactivas de Oxígeno/metabolismo , Serina-Treonina Quinasas TOR/metabolismoRESUMEN
FOXO3a (forkhead box transcription factor 3a) is involved in regulating multiple biological processes in cancer cells. BNIP3 (Bcl-2/adenovirus E1B 19-kDa-interacting protein 3) is a receptor accounting for priming damaged mitochondria for autophagic removal. In this study we investigated the role of FOXO3a in regulating the sensitivity of glioma cells to temozolomide (TMZ) and its relationship with BNIP3-mediated mitophagy. We showed that TMZ dosage-dependently inhibited the viability of human U87, U251, T98G, LN18 and rat C6 glioma cells with IC50 values of 135.75, 128.26, 142.65, 155.73 and 111.60 µM, respectively. In U87 and U251 cells, TMZ (200 µM) induced DNA double strand breaks (DSBs) and nuclear translocation of apoptosis inducing factor (AIF), which was accompanied by BNIP3-mediated mitophagy and FOXO3a accumulation in nucleus. TMZ treatment induced intracellular ROS accumulation in U87 and U251 cells via enhancing mitochondrial superoxide, which not only contributed to DNA DSBs and exacerbated mitochondrial dysfunction, but also upregulated FOXO3a expression. Knockdown of FOXO3a aggravated TMZ-induced DNA DSBs and mitochondrial damage, as well as glioma cell death. TMZ treatment not only upregulated BNIP3 and activated autophagy, but also triggered mitophagy by prompting BNIP3 translocation to mitochondria and reinforcing BNIP3 interaction with LC3BII. Inhibition of mitophagy by knocking down BNIP3 with SiRNA or blocking autophagy with 3MA or bafilomycin A1 exacerbated mitochondrial superoxide and intracellular ROS accumulation. Moreover, FOXO3a knockdown inhibited TMZ-induced BNIP3 upregulation and autophagy activation. In addition, we showed that treatment with TMZ (100 mg·kg-1·d-1, ip) for 12 days in C6 cell xenograft mice markedly inhibited tumor growth accompanied by inducing FOXO3a upregulation, oxidative stress and BNIP3-mediated mitophagy in tumor tissues. These results demonstrate that FOXO3a attenuates temozolomide-induced DNA double strand breaks in human glioma cells via promoting BNIP3-mediated mitophagy.
Asunto(s)
Antineoplásicos/uso terapéutico , Roturas del ADN de Doble Cadena/efectos de los fármacos , Proteína Forkhead Box O3/metabolismo , Glioma/metabolismo , Mitofagia/efectos de los fármacos , Temozolomida/uso terapéutico , Animales , Autofagia/efectos de los fármacos , Línea Celular Tumoral , Glioma/tratamiento farmacológico , Humanos , Proteínas de la Membrana/metabolismo , Ratones Endogámicos BALB C , Ratones Desnudos , Mitocondrias/efectos de los fármacos , Proteínas Mitocondriales/metabolismo , Estrés Oxidativo/efectos de los fármacos , Proteínas Proto-Oncogénicas/metabolismo , Ratas , Regulación hacia Arriba/efectos de los fármacosRESUMEN
Ferroptotic cell death is characterized by iron-dependent lipid peroxidation that is initiated by ferrous iron and H2O2 via Fenton reaction, in which the role of activating transcription factor 3 (ATF3) remains elusive. Brucine is a weak alkaline indole alkaloid extracted from the seeds of Strychnos nux-vomica, which has shown potent antitumor activity against various tumors, including glioma. In this study, we showed that brucine inhibited glioma cell growth in vitro and in vivo, which was paralleled by nuclear translocation of ATF3, lipid peroxidation, and increases of iron and H2O2. Furthermore, brucine-induced lipid peroxidation was inhibited or exacerbated when intracellular iron was chelated by deferoxamine (500 µM) or improved by ferric ammonium citrate (500 µM). Suppression of lipid peroxidation with lipophilic antioxidants ferrostatin-1 (50 µM) or liproxstatin-1 (30 µM) rescued brucine-induced glioma cell death. Moreover, knockdown of ATF3 prevented brucine-induced accumulation of iron and H2O2 and glioma cell death. We revealed that brucine induced ATF3 upregulation and translocation into nuclei via activation of ER stress. ATF3 promoted brucine-induced H2O2 accumulation via upregulating NOX4 and SOD1 to generate H2O2 on one hand, and downregulating catalase and xCT to prevent H2O2 degradation on the other hand. H2O2 then contributed to brucine-triggered iron increase and transferrin receptor upregulation, as well as lipid peroxidation. This was further verified by treating glioma cells with exogenous H2O2 alone. Moreover, H2O2 reversely exacerbated brucine-induced ER stress. Taken together, ATF3 contributes to brucine-induced glioma cell ferroptosis via increasing H2O2 and iron.
Asunto(s)
Factor de Transcripción Activador 3/metabolismo , Antineoplásicos/uso terapéutico , Ferroptosis/efectos de los fármacos , Peróxido de Hidrógeno/metabolismo , Hierro/metabolismo , Estricnina/análogos & derivados , Sistema de Transporte de Aminoácidos y+/metabolismo , Animales , Antineoplásicos/farmacología , Catalasa/metabolismo , Línea Celular Tumoral , Estrés del Retículo Endoplásmico/efectos de los fármacos , Humanos , Ratones Endogámicos BALB C , Ratones Desnudos , NADPH Oxidasa 4/metabolismo , Neoplasias/tratamiento farmacológico , Estricnina/farmacología , Estricnina/uso terapéutico , Superóxido Dismutasa-1/metabolismo , Regulación hacia Arriba/efectos de los fármacos , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
BACKGROUND: Guillain-Barré syndrome (GBS) is a common acute immune-mediated inflammatory disorder affecting the peripheral nervous system (PNS) of humans. Studies in humans and in animal models revealed that neuropeptide Y (NPY) levels are altered in some neurodegenerative and neuroimmune disorders. Herein, we investigated the levels of NPY and cytokines in the serum of GBS patients and explored the roles of NPY in the disease severity and its short-term prognosis. METHODS: Twenty patients with GBS (case group) and twenty healthy individuals (control group) were enrolled in this study. NPY levels were analyzed by enzyme-linked immunosorbent assay (ELISA). The levels of pro- and anti-inflammatory cytokines (including interferon-γ (IFN-γ), interleukin (IL)-4, IL-10, IL-12p70, IL-17A, and tumor necrosis factor-α (TNF-α)) were analyzed using cytometric beads array (CBA). The clinical characteristics, disease severity, and short-term prognosis were compared between the two groups. RESULTS: Compared with the control group, the levels of NPY and cytokines were significantly increased in the serum of patients with GBS. NPY levels in the serum of GBS patients were correlated with the disease severity. CONCLUSION: Our results suggest that NPY and cytokines are involved in the pathogenesis of GBS. The levels of NPY can help to predict the severity of the disease.
Asunto(s)
Citocinas/sangre , Citocinas/efectos de los fármacos , Síndrome de Guillain-Barré/sangre , Síndrome de Guillain-Barré/tratamiento farmacológico , Inmunoglobulinas Intravenosas/farmacología , Neuropéptido Y/sangre , Neuropéptido Y/efectos de los fármacos , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Síndrome de Guillain-Barré/fisiopatología , Humanos , Inmunoglobulinas Intravenosas/administración & dosificación , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Resultado del TratamientoRESUMEN
BACKGROUND: Heat stroke (HS) is a critical illness that can cause multiple organ dysfunction, including damage to the central nervous system (CNS), which can be life-threatening in severe cases. Brain lesions in patients with HS who present with CNS damage have been rarely reported before, and they usually vary in different cases, hence, patients with such lesions may present a clinical challenge in terms of diagnosis and management. Cerebral venous thrombosis (CVT) is a rare cause of stroke that mostly affects young individuals and children. The pathogenesis of brain damage caused by HS is complex, and CVT may be involved in the pathogenesis of HS with CNS damage. In this manuscript, we have reported a case of a patient with HS having CVT with symmetrical lesions in the bilateral putamen, posterior limb of the internal capsule, external capsule, insular lobe, and subcortical white matter in the brain. CASE PRESENTATION: We encountered a 48-year-old man who presented with HS in the summer season. During admission, he had a high body temperature and was in coma and shock. Then, he developed rhabdomyolysis syndrome, acute kidney and liver damage, electrolyte imbalance, and acid-base balance disorders, and his D-dimer level was elevated. After several days of anti-shock treatment, the patient's level of consciousness improved. However, he experienced a decline in vision. Cerebral magnetic resonance imaging (MRI) showed symmetrical lesions in the bilateral posterior limb of the internal capsule, putamen, external capsule, insula, and subcortical white matter, and cerebral magnetic resonance venography (MRV) showed the development of CVT. Therefore, anti-coagulation treatment was provided. After timely clinical intervention, the symptoms of the patient gradually improved. CONCLUSIONS: This case showed that HS can cause CVT. Therefore, cerebral MRI findings in HS must be assessed; in addition, early MRV can help in the diagnosis of the disease, which can effectively improve prognosis.
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Golpe de Calor/complicaciones , Golpe de Calor/diagnóstico por imagen , Golpe de Calor/patología , Trombosis Intracraneal/diagnóstico por imagen , Trombosis Intracraneal/etiología , Trombosis Intracraneal/patología , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Flebografía/métodosRESUMEN
Necroptosis is a type of programmed necrosis regulated by receptor interacting protein kinase 1 (RIP1) and RIP3. Necroptosis is found to be accompanied by an overproduction of reactive oxygen species (ROS), but the role of ROS in regulation of necroptosis remains elusive. In this study, we investigated how shikonin, a necroptosis inducer for cancer cells, regulated the signaling leading to necroptosis in glinoma cells in vitro. Treatment with shikonin (2-10 µmol/L) dose-dependently triggered necrosis and induced overproduction of intracellular ROS in rat C6 and human SHG-44, U87 and U251 glioma cell lines. Moreover, shikonin treatment dose-dependently upregulated the levels of RIP1 and RIP3 and reinforced their interaction in the glioma cells. Pretreatment with the specific RIP1 inhibitor Nec-1 (100 µmol/L) or the specific RIP3 inhibitor GSK-872 (5 µmol/L) not only prevented shikonin-induced glioma cell necrosis but also significantly mitigated the levels of intracellular ROS and mitochondrial superoxide. Mitigation of ROS with MnTBAP (40 µmol/L), which was a cleaner of mitochondrial superoxide, attenuated shikonin-induced glioma cell necrosis, whereas increasing ROS levels with rotenone, which improved the mitochondrial generation of superoxide, significantly augmented shikonin-caused glioma cell necrosis. Furthermore, pretreatment with MnTBAP prevented the shikonin-induced upregulation of RIP1 and RIP3 expression and their interaction while pretreatment with rotenone reinforced these effects. These findings suggest that ROS is not only an executioner of shikonin-induced glioma cell necrosis but also a regulator of RIP1 and RIP3 expression and necrosome assembly.
Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Neoplasias Encefálicas/tratamiento farmacológico , Glioma/tratamiento farmacológico , Naftoquinonas/farmacología , Proteínas de Complejo Poro Nuclear/metabolismo , Estrés Oxidativo/efectos de los fármacos , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas de Unión al ARN/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismo , Animales , Neoplasias Encefálicas/enzimología , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Glioma/enzimología , Glioma/patología , Humanos , Mitocondrias/efectos de los fármacos , Mitocondrias/enzimología , Mitocondrias/patología , Necrosis , Ratas , Transducción de Señal/efectos de los fármacos , Factores de TiempoRESUMEN
Cellular stress response after hypoxia-Ischemia (HI) may be substantially different between immature and mature brains. To study this phenomenon, postnatal day 7 (P7) and P26 rats were subjected to HI followed by different periods of recovery. Nuclear accumulation of heat-shock transcription factor-1 (HSF1) and expression of molecular chaperone proteins and mRNAs were analyzed by in situ hybridization, Western blotting and confocal microscopy. Nuclear accumulation of HSF1 protein and induction of hsp70 mRNA occurred dramatically in P26 neurons, but minimally in P7 neurons and moderately in microglial cells after HI. Consistently, the level of HSF1 was significantly higher in P26 brain samples, compared with that in P7 brain. Translation of hsp70 mRNA into proteins in P26 mature neurons was seen at 4h and peaked at 24h, when some neurons had already died after HI. Induction of ER glucose-regulated protein-78 (grp78) and mitochondrial hsp60 mRNAs and proteins was moderate and occurred also only in P26 mature brain after HI. These results suggest that the cellular stress response after HI is development-dependent, being pronounced in mature but virtually negligible in neonatal neurons. Therefore, the effectiveness of therapeutic strategies targeting the stress pathway against HI may be significantly different between immature and mature brains. The delayed induction of molecular chaperones in mature brain may be somewhat late for protecting HI neurons from acute HI injury.
Asunto(s)
Proteínas de Unión al ADN/metabolismo , Regulación del Desarrollo de la Expresión Génica , Proteínas HSP70 de Choque Térmico/metabolismo , Hipoxia-Isquemia Encefálica/metabolismo , Chaperonas Moleculares/metabolismo , Factores de Transcripción/metabolismo , Animales , Núcleo Celular/metabolismo , Proteínas de Unión al ADN/genética , Proteínas HSP70 de Choque Térmico/genética , Factores de Transcripción del Choque Térmico , Microglía/metabolismo , Chaperonas Moleculares/genética , Neuronas/metabolismo , Ratas , Ratas Sprague-Dawley , Factores de Transcripción/genéticaRESUMEN
BACKGROUND AND PURPOSE: Ischemic postconditioning has been demonstrated to be a protective procedure to brain damage caused by transient focal ischemia/reperfusion. However, it is elusive whether the protection of postconditioning against brain damage and neuroinflammation is via regulating TLR2 and TLR4 pathways. In the present study, we examined the protection of ischemic postconditioning performed immediately prior to the recovery of cerebral blood supply on brain damage caused by various duration of ischemia and tested the hypothesis that its protection is via inhibition of neuroinflammation by modulating TLR2/TLR4 pathways. METHODS: Brain damage in rats was induced by using the middle cerebral artery occlusion (MCAO) model. Ischemic postconditioning consisting of fivecycles of ten seconds of ischemia and reperfusion was performed immediately following theischemic episode Theduration of administration of ischemic postconditioning was examined by comparing its effects on infarction volume, cerebral edema and neurological function in 2, 3, 4, 4.5and 6 hour ischemia groups. The protective mechanism of ischemic postconditioning was investigated by comparing its effects on apoptosis, production of the neurotoxic cytokine IL-1ß and the transcription and expression of TLR2, TLR4 and IRAK4 in the 2 and 4.5 hour ischemia groups. RESULTS: Ischemic postconditioning significantly attenuated cerebral infarction, cerebral edema and neurological dysfunction in ischemia groups of up to 4 hours duration, but not in 4.5and 6 hour ischemia groups. It also inhibited apoptosis, production of IL-1ß, abnormal transcription and expression of TLR2, TLR4 and IRAK4 in the 2 hour ischemia group, but not in the 4.5 hour ischemia group. CONCLUSIONS: Ischemic postconditioning protected brain damage caused by 2, 3 and 4 hours of ischemia, but not by 4.5 and 6 hours of ischemia. The protection of ischemic postconditioning is associated with its inhibition of neuroinflammation via inhibition of TLR2 and TLR4 pathways.
Asunto(s)
Lesiones Encefálicas/prevención & control , Encefalitis/prevención & control , Poscondicionamiento Isquémico , Transducción de Señal/fisiología , Receptor Toll-Like 2/metabolismo , Receptor Toll-Like 4/metabolismo , Animales , Apoptosis , Edema Encefálico/etiología , Infarto Encefálico/etiología , Lesiones Encefálicas/etiología , Citocinas/metabolismo , Modelos Animales de Enfermedad , Encefalitis/etiología , Regulación de la Expresión Génica , Humanos , Infarto de la Arteria Cerebral Media/complicaciones , Masculino , Examen Neurológico , Ratas , Ratas Sprague-Dawley , Receptor Toll-Like 2/genética , Receptor Toll-Like 4/genéticaRESUMEN
Lethal autophagy is a pathway leading to neuronal death caused by transient global ischemia. In this study, we examined the effect of Ginsenoside Rb1 (GRb1) on ischemia/reperfusion-induced autophagic neuronal death and investigated the role of PI3K/Akt. Ischemic neuronal death in vitro was induced by using oxygen glucose deprivation (OGD) in SH-SY5Y cells, and transient global ischemia was produced by using two vessels occlusion in rats. Cellular viability of SH-SY5Y cells was assessed by MTT assay, and CA1 neuronal death was evaluated by Hematoxylin-eosin staining. Autophagic vacuoles were detected by using both fluorescent microscopy in combination with acridine orange (AO) and Monodansylcadaverine (MDC) staining and transmission electronic microscopy. Protein levels of LC3II, Beclin1, total Akt and phosphor-Akt at Ser473 were examined by western blotting analysis. GRb1 inhibited both OGD and transient ischemia-induced neuronal death and mitigated OGD-induced autophagic vacuoles in SH-SY5Y cells. By contrast, PI3K inhibitor LY294002 counteracted the protection of GRb1 against neuronal death caused by either OGD or transient ischemia. LY294002 not only mitigated the up-regulated protein level of phosphor Akt at Ser473 caused by GRb1, but also reversed the inhibitory effect of GRb1 on OGD and transient ischemia-induced elevation in protein levels of LC3II and Beclin1.
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Autofagia/efectos de los fármacos , Isquemia Encefálica/tratamiento farmacológico , Región CA1 Hipocampal/patología , Ginsenósidos/uso terapéutico , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/uso terapéutico , Fosfatidilinositol 3-Quinasas/fisiología , Fitoterapia , Proteínas Proto-Oncogénicas c-akt/fisiología , Transducción de Señal/efectos de los fármacos , Animales , Proteínas Reguladoras de la Apoptosis/biosíntesis , Proteínas Reguladoras de la Apoptosis/genética , Beclina-1 , Isquemia Encefálica/patología , Región CA1 Hipocampal/irrigación sanguínea , Línea Celular Tumoral , Cromonas/farmacología , Activación Enzimática/efectos de los fármacos , Ginsenósidos/antagonistas & inhibidores , Ginsenósidos/farmacología , Glucosa/farmacología , Humanos , Masculino , Proteínas Asociadas a Microtúbulos/biosíntesis , Proteínas Asociadas a Microtúbulos/genética , Morfolinas/farmacología , Proteínas del Tejido Nervioso/biosíntesis , Proteínas del Tejido Nervioso/genética , Neuroblastoma/patología , Neuronas/metabolismo , Neuronas/ultraestructura , Fármacos Neuroprotectores/antagonistas & inhibidores , Fármacos Neuroprotectores/farmacología , Oxígeno/farmacología , Distribución Aleatoria , Ratas , Ratas Wistar , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/etiología , Daño por Reperfusión/prevención & control , Regulación hacia Arriba/efectos de los fármacosRESUMEN
Maltol, a chemical isolated from ginseng root, has shown treatment effects on several pathological processes including osteoarthritis, diabetic peripheral neuropathy and liver fibrosis. Nevertheless, its effect on ischemiainduced neuron death remains elusive. In the present study, the treatment effect of maltol on ischemiainduced neuron damage was investigated by using oxygen and glucose deprivation (OGD) model in SHSY5Y cells. In vitro studies revealed that maltol protected SHSY5Y cells against OGDinduced chromatinolysis by inhibiting two reactive oxygen species (ROS)regulated pathways. One was DNA doublestrand breaks and the other was nuclear translocation of apoptosis inducing factor. Mechanistically, maltol not only inhibited OGDinduced depletion of glutathione and cysteine by maintaining cystine/glutamate antiporter (xCT) level, but also abrogated OGDinduced catalase downregulation. Meanwhile, maltol also alleviated OGDinduced inactivation of mTOR by attenuating OGDinduced depletion of adenosine triphosphate and pyruvate and downregulation of pyruvate kinase M2, indicating that maltol inhibited the glycolysis dysfunction caused by OGD. Considering that activated mammalian target of the rapamycin (mTOR) could lead to enhanced xCT expression and decreased catalase degradation by autophagy, these findings indicated that maltol attenuated OGDinduced ROS via inhibition of mTOR inactivation by maintaining pyruvate level. Taken together, it was demonstrated that maltol prevented OGDinduced chromatinolysis in SHSY5Y cells via inhibiting pyruvate depletion.
Asunto(s)
Neuroblastoma , Oxígeno , Humanos , Oxígeno/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Ácido Pirúvico , Glucosa/metabolismo , Catalasa , Serina-Treonina Quinasas TOR/metabolismoRESUMEN
The effects of early relief of heavy bilateral carotid stenosis and ischemic postconditioning on hippocampus CA1 neurons are still unclear. In this study, we used a rat model to imitate severe bilateral carotid stenosis in humans. The rats were divided into sham group, carotid stenosis group, stenosis relief group and ischemic postconditioning group. Ischemic postconditioning consisted of three cycles of 30 s ischemia and 30 s reperfusion. The cerebral blood flow was measured with a laser Doppler flowmeter. Neuronal death in the CA1 region was observed by hematoxylin-eosin staining, and the number of live neurons was assessed by cell counting under a light microscope. The levels of oxidative products MDA and 8-iso-PGF2α, inflammatory factors IL-1ß and TNF-α, and the activities of anti-oxidative enzymes SOD and CAT were assayed by specific enzyme-linked immunosorbent assay (ELISA) kits, respectively. We found that relief of carotid stenosis and ischemic postconditioning could increase cerebral blood flow. When stenosis was relieved, the percentage of live neurons was 66.6% ± 6.2% on day 3 and 62.3% ± 9.8% on day 27, which was significantly higher than 55.5% ± 4.8% in stenosis group. Ischemic postconditioning markedly improved the live neurons to 92.5% ± 6.7% on day 3 and 88.6% ± 9.1% on day 27. Further study showed that, neuronal death caused by relief of stenosis is associated with increased oxidative stress and enhanced inflammatory response, and the protection of ischemic postconditioning is related to inhibition of oxidative stress and suppression of inflammatory response.
Asunto(s)
Estenosis Carotídea/patología , Hipocampo/patología , Poscondicionamiento Isquémico , Animales , Apoptosis , Estenosis Carotídea/metabolismo , Catalasa/análisis , Dinoprost/análogos & derivados , Dinoprost/análisis , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática , Hipocampo/lesiones , Hipocampo/metabolismo , Interleucina-1beta/análisis , Masculino , Malondialdehído/análisis , Ratas , Ratas Wistar , Superóxido Dismutasa/análisis , Factor de Necrosis Tumoral alfa/análisisRESUMEN
Shikonin induces glioma cell death via necroptosis, a caspase-independent programmed cell death pathway that is chiefly regulated by receptor-interacting serine/threonine protein kinase1 (RIP1) and 3 (RIP3). Chromatinolysis is considered as one of the key events leading to cell death during necroptosis. It is usually accompanied with nuclear translocation of AIF and formation of γ-H2AX. Cyclophilin A (CypA) is reported to participate in the nuclear translocation of AIF during apoptosis. However, it remains unclear whether CypA contributes to necroptosis and regulation of chromatinolysis. In this study, our results revealed for the first time that shikonin promoted time-dependent CypA activation, which contributed to nuclear translocation of AIF and γ-H2AX formation. In vitro studies showed that knockdown of CypA by siRNA or inhibition of CypA by its specific inhibitor, cyclosporine A (CsA), not only significantly mitigated shikonin-induced glioma cell death, but also prevented chromatinolysis. Mechanistically, activated CypA targeted mitochondria and triggered mitochondrial superoxide overproduction, which then promoted AIF translocation from mitochondria into the nucleus by depolarizing the mitochondria and intensified the formation of γ-H2AX by promoting intracellular accumulation of ROS. Additionally, the CypA in the nucleus can form DNA degradation complexes with AIF and γ-H2AX, which also promote the execution of chromatinolysis. Thus, we demonstrate that CypA contributes to shikonin-induced glioma cell necroptosis and promotion of chromatinolysis.
Asunto(s)
Glioma , Necroptosis , Apoptosis , Factor Inductor de la Apoptosis/metabolismo , Ciclofilina A/metabolismo , Glioma/metabolismo , Humanos , Naftoquinonas , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismoRESUMEN
INTRODUCTION: Dandy-Walker complex and pleomorphic xanthoastrocytomas are both rare disease entities that typically manifest early in life and are associated with congenital etiological factors. Dandy-Walker complex is a cerebellar malformation associated with a series of anatomical changes. The disease onset is usually at birth or during infancy. Late onset in adulthood is uncommon. Pleomorphic xanthoastrocytoma is a rare WHO grade II astrocytic tumor affecting mainly young adults. Concomitant occurrence of Dandy-Walker complex and pleomorphic xanthoastrocytoma has not been previously reported. PATIENT CONCERNS AND DIAGNOSIS: A 30-year-old woman with a previous history of unconfirmed resected lateral ventricle meningioma presented with severe headache for 1 day. Imaging examination revealed a mass in the right lateral ventricle with heterogeneous signal patterns, changes in the posterior fossa corresponding to a Dandy-Walker variant, and mild hydrocephalus. INTERVENTIONS AND OUTCOMES: Surgical complete resection of the mass was achieved. postoperative histopathological examination confirmed WHO grade II pleomorphic xanthoastrocytoma. Three years postsurgery, ventriculoperitoneal shunt was performed due to worsening of hydrocephalus. The patient has since remained symptom-free. CONCLUSION: This is the first report of concomitant occurrence of Dandy-Walker complex and pleomorphic xanthoastrocytoma. The association of neurological congenital malformation with intracranial neoplasms may be multifactorial, with underlying role of genetic mutations or chromosome alterations.
Asunto(s)
Astrocitoma , Síndrome de Dandy-Walker , Hidrocefalia , Adulto , Astrocitoma/complicaciones , Astrocitoma/cirugía , Síndrome de Dandy-Walker/complicaciones , Síndrome de Dandy-Walker/diagnóstico , Síndrome de Dandy-Walker/cirugía , Femenino , Humanos , Hidrocefalia/etiología , Recién Nacido , Ventrículos Laterales/patología , Derivación Ventriculoperitoneal/efectos adversosRESUMEN
Kikuchi-Fujimoto disease (KFD), also known as histiocytic necrotizing lymphadenitis, is a rare, benign, self-limiting disease characterized by local lymphadenopathy. Central nervous system involvement in KFD is extremely rare and remains a diagnostic challenge. Only 41 cases of aseptic meningitis associated with KFD have been reported worldwide, with just four cases (including our case) of KFD with meningitis as the first symptom. We report a case of KFD accompanied by aseptic meningitis with severely high intracranial pressure (400 mmH2O), increased white blood cell count (56 × 106/L), and moderately elevated protein level (0.52 g/L). This case is unique in the delayed appearance of lymphadenopathy. After 1 month of treatment with steroids, fever, headache, and lymphadenopathy gradually disappeared, and the result of cerebrospinal fluid examination gradually became normal. In conclusion, based on our case findings and our literature review on KFD with aseptic meningitis, a diagnosis of KFD should be considered when delayed appearance of lymphadenopathy is observed in patients with aseptic meningitis.
RESUMEN
Protein aggregation has been proved to be a pathological basis accounting for neuronal death caused by either transient global ischemia or oxygen glucose deprivation (OGD), and inhibition of protein aggregation is emerging as a potential strategy of preventing brain damage. Trehalose was found to inhibit protein aggregation caused by neurodegenerative diseases via induction of autophagy, whereas its effect is still elusive on ischemia-induced protein aggregation. In this study, we investigated this issue by using rat model of transient global ischemia and SH-SY5Y model of OGD. We found that pretreatment with trehalose inhibited transient global ischemia-induced neuronal death in the hippocampus CA1 neurons and OGD-induced death in SH-SY5Y cells, which was associated with inhibition of the formation of ubiquitin-labeled protein aggregates and preservation of proteasome activity. In vitro study showed that the protection of trehalose against OGD-induced cell death and protein aggregation in SH-SY5Y cells was reversed when proteasome activity was inhibited by MG-132. Further studies revealed that trehalose prevented OGD-induced reduction of proteasome activity via suppression of both oxidative stress and endoplasmic reticulum stress. Particularly, our results showed that trehalose inhibited OGD-induced autophagy. Therefore, we demonstrated that proteasome dysfunction contributed to protein aggregation caused by ischemic insults and trehalose prevented protein aggregation via preservation of proteasome activity, not via induction of autophagy.
Asunto(s)
Autofagia/fisiología , Isquemia Encefálica/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Agregación Patológica de Proteínas/metabolismo , Trehalosa/farmacología , Animales , Autofagia/efectos de los fármacos , Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/patología , Línea Celular Tumoral , Humanos , Masculino , Agregación Patológica de Proteínas/tratamiento farmacológico , Agregación Patológica de Proteínas/patología , Ratas , Ratas Wistar , Trehalosa/uso terapéuticoRESUMEN
Parthanatos is a form of PARP-1-dependent programmed cell death. The induction of parthanatos is emerging as a new strategy to kill gliomas which are the most common type of primary malignant brain tumor. Oxidative stress is thought to be a critical factor triggering parthanatos, but its underlying mechanism is poorly understood. In this study, we used glioma cell lines and H2O2 to investigate the role of JNK in glioma cell parthanatos induced by oxidative stress. We found that exposure to H2O2 not only induced intracellular accumulation of ROS but also resulted in glioma cell death in a concentration- and incubation time-dependent manner, which was accompanied with cytoplasmic formation of PAR polymer, expressional upregulation of PARP-1, mitochondrial depolarization, and AIF translocation to nucleus. Pharmacological inhibition of PARP-1 with 3AB or genetic knockdown of its level with siRNA rescued glioma cell death, as well as suppressed cytoplasmic accumulation of PAR polymer and nuclear translocation of AIF, which were consistent with the definition of parthanatos. Moreover, the phosphorylated level of JNK increased markedly with the extension of H2O2 exposure time. Either attenuation of intracellular ROS with antioxidant NAC or inhibition of JNK phosphorylation with SP600125 or JNK siRNA could significantly prevent H2O2-induced parthanatos in glioma cells. Additionally, inhibition of JNK with SP600125 alleviated intracellular accumulation of ROS and attenuated mitochondrial generation of superoxide. Thus, we demonstrated that JNK activation contributes to glioma cell parthanatos caused by oxidative stress via increase of intracellular ROS generation.
Asunto(s)
Neoplasias Encefálicas/enzimología , Neoplasias Encefálicas/patología , Glioma/enzimología , Glioma/patología , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Estrés Oxidativo , Poli(ADP-Ribosa) Polimerasa-1/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Acetilcisteína/farmacología , Antioxidantes/farmacología , Apoptosis , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Humanos , Peróxido de Hidrógeno/toxicidad , Espacio Intracelular/metabolismo , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Estrés Oxidativo/efectos de los fármacos , ARN Interferente Pequeño/metabolismo , Superóxidos/metabolismoRESUMEN
Shikonin has been reported to induce glioma cell death via necroptosis, a type of programmed necrosis primarily mediated by RIP1 and RIP3. Although RIP1 and RIP3 are found to regulate some features of necrosis such as energy depletion and cellular membrane disruption, it remains unclear whether RIP1 and RIP3 could modulate DNA double strand breaks (DSBs), which is a crucial event leading to chromatinolysis. In this study, we used glioma cell lines and mice model of xenograft glioma to investigate the roles of RIP1 and RIP3 in shikonin-induced DNA DSBs. We found that shikonin induced upregulation of RIP1 and RIP3, necrosome formation and DNA DSBs in vitro and in vivo. In vitro investigation showed that the DNA DSBs and the reduction of cellular viabilities induced by shikonin were both prevented when RIP1 or RIP3 was pharmacologically inhibited by specific inhibitor or genetically knocked down with siRNA. Then, we proved that suppression of intracellular ROS with antioxidant NAC inhibited DNA DSBs caused by either hydrogen peroxide or shikonin, suggesting that ROS played a crucial role in regulation of DNA DSBs of glioma cells induced by shikonin. Further, we found that RIP1 and RIP3 regulated shikonin-induced overproduction of ROS via causing excessive generation of mitochondrial superoxide and depletion of GSH, indicating that ROS was the downstream signal of RIP1 and RIP3. Taken together, we demonstrated that RIP1 and RIP3 contributed to shikonin-induced DNA DSBs in glioma cells via increase of intracellular ROS levels.
Asunto(s)
Roturas del ADN de Doble Cadena , Glioma/tratamiento farmacológico , Proteínas de Complejo Poro Nuclear/metabolismo , Proteínas de Unión al ARN/metabolismo , Especies Reactivas de Oxígeno , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismo , Animales , Línea Celular Tumoral , Roturas del ADN de Doble Cadena/efectos de los fármacos , Modelos Animales de Enfermedad , Xenoinjertos , Ratones , Naftoquinonas/farmacología , Proteínas de Complejo Poro Nuclear/genética , Proteínas de Unión al ARN/genética , Proteína Serina-Treonina Quinasas de Interacción con Receptores/genética , Regulación hacia ArribaRESUMEN
Oxidative stress, which is characterized by excessive production of reactive oxygen species (ROS), is a common pathway that results in neuronal injury or death due to various types of pathological stress. Although lycopene has been identified as a potent antioxidant, its effect on hydrogen peroxide (H2O2)induced neuronal damage remains unclear. In the present study, pretreatment with lycopene was observed to protect SHSY5Y neuroblastoma cells against H2O2induced death via inhibition of apoptosis resulting from activation of caspase3 and translocation of apoptosis inducing factor (AIF) to the nucleus. Furthermore, the overproduced ROS, as well as the reduced activities of antioxidative enzymes, superoxide dismutase and catalase, were demonstrated to be alleviated by lycopene. Additionally, lycopene counteracted H2O2induced mitochondrial dysfunction, which was evidenced by suppression of mitochondrial permeability transition pore opening, attenuation of the decline of the mitochondrial membrane potential, and inhibition of the increase of Bax and decrease of Bcl2 levels within the mitochondria. The release of cytochrome c and AIF from the mitochondria was also reduced. These results indicate that lycopene is a potent neuroprotectant against apoptosis, oxidative stress and mitochondrial dysfunction, and could be administered to prevent neuronal injury or death.
Asunto(s)
Apoptosis/efectos de los fármacos , Carotenoides/farmacología , Peróxido de Hidrógeno/farmacología , Mitocondrias/metabolismo , Neuroblastoma/metabolismo , Estrés Oxidativo/efectos de los fármacos , Línea Celular Tumoral , Humanos , Licopeno , Mitocondrias/patología , Neuroblastoma/patologíaRESUMEN
Programmed necrosis is established as a new form of programmed cell death and is emerging as a new strategy of treatment for cancers. Pristimerin is a natural chemical with anti-tumor effect despite the fact that its mechanism remains poorly understood. In this study, we used glioma cell lines and mice model of xenograft glioma to investigate the effect of pristimerin on glioma and its underlying mechanism. We found that pristimerin inhibited the viabilities of glioma cells in vitro and the growth of xenograft gliomas in vivo, which was accompanied by upregulation of JNK and phosphor-JNK, nuclear accumulation of AIF, and elevation in the ratio of Bax/Bcl-2. In vitro studies showed that pristimerin induced necrosis in glioma cells, as well as mitochondrial depolarization, overproduction of ROS and reduction of GSH. Ablation of AIF level with SiRNA mitigated pristimerin-induced nuclear accumulation of AIF and prevented necrosis in glioma cells. Moreover, pharmacological inhibition of JNK with SP600125 or knockdown of its level with SiRNA reversed mitochondrial depolarization attenuated the elevation of Bax/Bcl-2 and suppressed nuclear accumulation of AIF. Further, inhibition of ROS with NAC not only rescued glioma cell necrosis but also suppressed JNK activation, mitigated Bax/Bcl-2 ratio, maintained mitochondrial membrane potential, and inhibited AIF translocation into nucleus. Therefore, we demonstrated first in this study that pristimerin triggered AIF-dependent necroptosis in glioma cells via induction of mitochondrial dysfunction by activation of JNK through overproduction of ROS. These results suggest that pristimerin has potential therapeutic effects on glioma.
Asunto(s)
Antineoplásicos/farmacología , Factor Inductor de la Apoptosis/metabolismo , Glioma/tratamiento farmacológico , MAP Quinasa Quinasa 4/metabolismo , Triterpenos/farmacología , Animales , Procesos de Crecimiento Celular/efectos de los fármacos , Línea Celular Tumoral , Activación Enzimática/efectos de los fármacos , Glioma/metabolismo , Glioma/patología , Humanos , Ratones Endogámicos BALB C , Ratones Desnudos , Necrosis , Triterpenos Pentacíclicos , Ratas , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Parthanatos is a new form of programmed cell death that is regulated by hyper-activated PARP-1, and is emerging as a new strategy to kill cancer cells. Deoxypodophyllotoxin (DPT) is a natural chemical that is found to induce cancer cell death, in which the role of parthanatos is unknown. Thus, we investigated this issue in this study by using glioma cell lines and mice model of xenograft glioma. We found that DPT induced glioma cell death in vitro and inhibited the growth of xenograft glioma in vivo, which was accompanied with parthanatos-related biochemical events including expressional upregulation of PARP-1, cytoplasmic accumulation of PAR polymer, and nuclear translocation of AIF. In vitro study revealed that genetic knockdown of PARP-1 with small interfering RNA attenuated DPT-induced elevation in the cytoplasmic PAR-polymer and the nuclear AIF, as well as protected glioma cells against the toxicity of DPT. Further, antioxidant NAC, as well as PARP-1 inhibitor 3AB, not only alleviated the overproduction of ROS caused by DPT, but also reversed the above-mentioned biochemical events, maintained mitochondrial membrane potential and rescued glioma cells death. Therefore, we demonstrated that deoxypodophyllotoxin triggered parthanatos in glioma cells via induction of excessive ROS.