RESUMEN
The male neonate in this case study was admitted to the hospital at 15 hours of age due to respiratory distress for 15 hours and poor response for 3 hours after resuscitation from asphyxia. The neonate was highly unresponsive, with central respiratory failure and seizures. Serum ammonia was elevated (>1 000 µmol/L). Blood tandem mass spectrometry revealed a significant decrease in citrulline. Rapid familial whole genome sequencing revealed OTC gene mutations inherited from the mother. Continuous hemodialysis filtration and other treatments were given. Neurological assessment was performed by cranial magnetic resonance imaging and electroencephalogram. The neonate was diagnosed with ornithine transcarbamylase deficiency combined with brain injury. He died at 6 days of age after withdrawing care. This article focuses on the differential diagnosis of neonatal hyperammonemia and introduces the multidisciplinary management of inborn error of metabolism.
Asunto(s)
Hiperamonemia , Enfermedad por Deficiencia de Ornitina Carbamoiltransferasa , Humanos , Recién Nacido , Masculino , Citrulina , Electroencefalografía , Enfermedad por Deficiencia de Ornitina Carbamoiltransferasa/diagnóstico , Enfermedad por Deficiencia de Ornitina Carbamoiltransferasa/terapia , ConvulsionesRESUMEN
BACKGROUND: The underlying cause of neurological sequelae after immature cerebral hypoxia-ischaemia (HI) white matter injury is impaired myelination. Previous studies have indicated that astrocyte activation is closely related to impaired myelination. However, the mechanism of reactive gliosis in white matter injury post-HI remains poorly understood. METHODS: Studies using adult ischaemic animal models demonstrated that hypoxia inducible factor-1α (HIF-1α) expression was involved in the formation of reactive astrocytes. Here, we investigated the temporal expression of HIF-1α and its impact on reactive gliosis and further myelination using a perinatal HI white matter injury model induced in rats at postnatal day 3. The temporal pattern of HIF-1α expression post-HI injury was tested by western blotting and immunofluorescence. Rats were treated with a HIF-1α inhibitor at 72 hours post-HI injury. Reactive gliosis and myelination were assessed with western blotting, immunofluorescence and electron microscopy, and neurological functions were examined by behavioural testing. RESULTS: Our results showed that the expression of HIF-1α was upregulated in neurons at 24 hours and in astrocytes at 7 days post-HI. Inhibiting delayed HIF-1α expression post-HI injury could restrain reactive gliosis, ameliorate hypomyelination, and improve the performance of rats in the Morris water maze test. CONCLUSIONS: Our findings suggest that a delayed increase in HIF-1α in astrocytes is involved in glial scar formation and leads to arrested oligodendrocyte maturation, impaired myelination, and long-term neurological function after experimental white matter injury in immature rats.
RESUMEN
Angiotensin II (AngII) is an important factor that promotes the proliferation of cancer cells, whereas celastrol exhibits a significant antitumor activity in various cancer models. Whether celastrol can effectively suppress AngII mediated cell proliferation remains unknown. In this study, we studied the effect of celastrol on AngII-induced HepG2 cell proliferation and evaluated its underlying mechanism. The results revealed that AngII was able to significantly promote HepG2 cell proliferation via up-regulating AngII type 1 (AT1) receptor expression, improving mitochondrial respiratory function, enhancing nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity, increasing the levels of reactive oxygen species (ROS) and pro-inflammatory cytokines. The excess ROS from mitochondrial dysfunction is able to cause the apoptosis of tumor cells via activating caspase3 signal pathway. In addition, the reaction between NO and ROS results in the formation of peroxynitrite (ONOO-), and then promoting cell damage. celastrol dramatically enhanced ROS generation, thereby causing cell apoptosis through inhibiting mitochodrial respiratory function and boosting the expression levels of AngII type 2 (AT2) receptor without influencing NADPH oxidase activity. PD123319 as a special inhibitor of AT2R was able to effectively decreased the levels of inflammatory cytokines and endothelial nitric oxide synthase (eNOS) activity, but only partially attenuate the effect of celastrol on AnII mediated HepG2 cell proliferation. Thus, celastrol has the potential for use in liver cancer therapy. ROS derived from mitochondrial is an important factor for celastrol to suppress HepG2 cell proliferation.
Asunto(s)
Angiotensina II/metabolismo , Apoptosis/efectos de los fármacos , Mitocondrias/metabolismo , NADPH Oxidasas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Triterpenos/farmacología , Angiotensina II/genética , Proliferación Celular/efectos de los fármacos , Células Hep G2 , Humanos , Mitocondrias/efectos de los fármacos , NADPH Oxidasas/genética , Óxido Nítrico Sintasa de Tipo III/genética , Óxido Nítrico Sintasa de Tipo III/metabolismo , Triterpenos Pentacíclicos , Transducción de Señal/efectos de los fármacosRESUMEN
Retinoic acid (RA) plays an important role in lung development and maturation. Many stimuli can induce alveolar epithelial cell damage which will result in the injury of lung parenchyma. The aim of this study was to observe the effect of RA on the proliferation and differentiation of primary fetal alveolar epithelial type II cells (fAECIIs). Primary fAECIIs were isolated from fetal rats at 19 d of gestation and purified by a differential centrifugation and adhesion method. The cells were randomly divided into control (dimethyl sulfoxide, DMSO) and RA groups. Cell proliferation, viability, apoptosis, cycle, and expression of target protein were examined at 24, 48, and 72 h. We found that the proliferation and viability of cells in the RA-exposed group significantly increased compared with the DMSO control group. The proportion (%) of cells in the G2 and S phases in the RA group was significantly higher than that in control group cells. The proportion (%) of both early apoptotic cells and late apoptotic cells decreased significantly in cells exposed to RA compared with cells exposed to DMSO. RA significantly enhanced the expression of aquaporin 5 (AQP5). The expression level of pulmonary surfactant C (SPC) was elevated after cells were exposed to RA for 24 and 72 h but was inhibited when cells were exposed to RA for 48 h. These results suggest that RA promotes fAECII proliferation by improving cell viability, promoting S phase entry and inhibiting apoptosis and RA promotes fAECIIs differentiation to alveolar epithelial type I cells (AECIs).