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High mobility group protein B1 (HMGB1) acts as a pathogenic inflammatory response to mediate ranges of conditions such as epilepsy, septic shock, ischemia, traumatic brain injury, Parkinson's disease, Alzheimer's disease and mass spectrometry. HMGB1 promotes inflammation during sterile and infectious damage and plays a crucial role in disease development. Mobilization from the nucleus to the cytoplasm is the first important step in the release of HMGB1 from activated immune cells. Here, we demonstrated that Sirtuin 2 (SIRT2) physically interacts with and deacetylates HMGB1 at 43 lysine residue at nuclear localization signal locations, strengthening its interaction with HMGB1 and causing HMGB1 to be localized in the cytoplasm. These discoveries are the first to shed light on the SIRT2 nucleoplasmic shuttle, which influences HMGB1 and its degradation, hence revealing novel therapeutic targets and avenues for neuroinflammation treatment.
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NAD-dependent deacetylase Sirt2 is involved in mammalian metabolic activities, matching energy demand with energy production and expenditure, and is relevant to a variety of metabolic diseases. Here, we constructed Sirt2 knockout and adeno-associated virus overexpression mice and found that deletion of hepatic Sirt2 accelerated primary obesity and insulin resistance in mice with concomitant hepatic metabolic dysfunction. However, the key targets of Sirt2 are unknown. We identified the M2 isoform of pyruvate kinase (PKM2) as a key Sirt2 target involved in glycolysis in metabolic stress. Through yeast two-hybrid and mass spectrometry combined with multi-omics analysis, we identified candidate acetylation modification targets of Sirt2 on PKM2 lysine 135 (K135). The Sirt2-mediated deacetylation-ubiquitination switch of PKM2 regulated the development of glycolysis. Here, we found that Sirt2 deficiency led to impaired glucose tolerance and insulin resistance and induced primary obesity. Sirt2 severely disrupted liver function in mice under metabolic stress, exacerbated the metabolic burden on the liver, and affected glucose metabolism. Sirt2 underwent acetylation modification of lysine 135 of PKM2 through a histidine 187 enzyme active site-dependent effect and reduced ubiquitination of the K48 ubiquitin chain of PKM2. Our findings reveal that the hepatic glucose metabolism links nutrient state to whole-body energetics through the rhythmic regulation of Sirt2.
Assuntos
Fígado , Piruvato Quinase , Sirtuína 2 , Estresse Fisiológico , Ubiquitinação , Animais , Humanos , Masculino , Camundongos , Acetilação , Glucose/metabolismo , Glicólise , Resistência à Insulina , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Obesidade/metabolismo , Piruvato Quinase/metabolismo , Sirtuína 2/metabolismoRESUMO
O-GlcNAcylation is a dynamic, reversible and atypical O-glycosylation that regulates various cellular physiological processes via conformation, stabilisation, localisation, chaperone interaction or activity of target proteins. The O-GlcNAcylation cycle is precisely controlled by collaboration between O-GlcNAc transferase and O-GlcNAcase. Uridine-diphosphate-N-acetylglucosamine, the sole donor of O-GlcNAcylation produced by the hexosamine biosynthesis pathway, is controlled by the input of glucose, glutamine, acetyl coenzyme A and uridine triphosphate, making it a sensor of the fluctuation of molecules, making O-GlcNAcylation a pivotal nutrient sensor for the metabolism of carbohydrates, amino acids, lipids and nucleotides. O-GlcNAcylation, particularly prevalent in liver, is the core hub for controlling systemic glucose homeostasis due to its nutritional sensitivity and precise spatiotemporal regulation of insulin signal transduction. The pathology of various liver diseases has highlighted hepatic metabolic disorder and dysfunction, and abnormal O-GlcNAcylation also plays a specific pathological role in these processes. Therefore, this review describes the unique features of O-GlcNAcylation and its dynamic homeostasis maintenance. Additionally, it explains the underlying nutritional sensitivity of O-GlcNAcylation and discusses its mechanism of spatiotemporal modulation of insulin signal transduction and liver metabolic homeostasis during the fasting and feeding cycle. This review emphasises the pathophysiological implications of O-GlcNAcylation in nonalcoholic fatty liver disease, nonalcoholic steatohepatitis and hepatic fibrosis, and focuses on the adverse effects of hyper O-GlcNAcylation on liver cancer progression and metabolic reprogramming.
Assuntos
Hepatopatia Gordurosa não Alcoólica , Transdução de Sinais , Humanos , Glicosilação , Processamento de Proteína Pós-Traducional , Insulina , GlucoseRESUMO
Angiolipomas are slow-growing benign mesenchymal-derived tumors consisting of mature adipocytes and thin-walled blood vessels. While the majority of angiolipomas are found in subcutaneous tissues, rarely there are case reports of intracranial lesions. We present a case of cisternal angiolipoma in a 10-year-old female. She presented with vague symptoms like dizziness without neurological deficits and radiological evaluation confirmed a left-sided infratentorial cisternal partially enhancing mass. She underwent craniotomy and had complete resection of the mass, which was histologically composed of mature adipocytes and blood vessels, consistent with angiolipoma. A review of the literature found only 18 cases of intracranial angiolipoma ever reported with our case representing the first case of infratentorial cisternal region.
Assuntos
Angiolipoma , Feminino , Humanos , Criança , Angiolipoma/diagnóstico por imagem , Angiolipoma/cirurgia , Radiografia , Tela Subcutânea/patologia , Tela Subcutânea/cirurgia , CraniotomiaRESUMO
RNA-binding motif protein 3 (RBM3), an outstanding cold shock protein, is rapidly upregulated to ensure homeostasis and survival in a cold environment, which is an important physiological mechanism in response to cold stress. Meanwhile, RBM3 has multiple physiological functions and participates in the regulation of various cellular physiological processes, such as antiapoptosis, circadian rhythm, cell cycle, reproduction, and tumogenesis. The structure, conservation, and tissue distribution of RBM3 in human are demonstrated in this review. Herein, the multiple physiological functions of RBM3 were summarized based on recent research advances. Meanwhile, the cytoprotective mechanism of RBM3 during stress under various adverse conditions and its regulation of transcription were discussed. In addition, the neuroprotection of RBM3 and its oncogenic role and controversy in various cancers were investigated in our review.
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Proteínas e Peptídeos de Choque Frio , Hipotermia , Proteínas e Peptídeos de Choque Frio/genética , Proteínas e Peptídeos de Choque Frio/metabolismo , Temperatura Baixa , Resposta ao Choque Frio , Humanos , Hipotermia/metabolismo , Neuroproteção , Proteínas de Ligação a RNA/metabolismoRESUMO
Cold exposure is an unavoidable and severe challenge for people and animals residing in cold regions of the world, and may lead to hypothermia, drastic changes in systemic metabolism, and inhibition of protein synthesis. O-linked-N-acetylglucoseaminylation (O-GlcNAcylation) directly regulates the activity and function of target proteins involved in multiple biological processes by acting as a stress receptor and nutrient sensor. Therefore, our study aimed to examine whether O-GlcNAcylation affected myogenic IL-6 expression, regulation of energy metabolism, and promotion of survival in mouse skeletal muscle under acute cold exposure conditions. Total protein was extracted from C2C12 cells that had been cultured at 32°C for 3, 6, 9, and 12 h. Western blot analysis showed that mild hypothermia enhanced O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA) expression. Furthermore, global OGT-dependent glycosylation and interleukin-6 (IL-6) levels peaked 3 h after induction of mild hypothermia. Enhanced activation of the NF-κB pathway was also observed in response to mild hypothermia. Alloxan and Thiamet G were used to reduce and increase global OGT glycosylation levels in C2C12 cells, respectively. Increased O-GlcNAcylation was associated with significant upregulation of IL-6 expression, as well as enhanced activity and nuclear translocation of p65, while decreased O-GlcNAcylation had the opposite effect. In addition, increased O-GlcNAcylation was associated with significantly increased glucose metabolism, and OGT-mediated O-GlcNAcylation of p65. We generated skeletal muscle-specific OGT knockout mice and exposed them to cold at 4°C for 3 h per day for 1 week. OGT deficiency attenuated the O-GlcNAcylation, activity, and nuclear translocation of p65, resulting in downregulation of IL-6 in mouse skeletal muscle of mice exposed to cold conditions. Taken together, our data suggested that O-GlcNAcylation of p65 enhanced p65 activity and nuclear translocation leading to the upregulation of IL-6, which maintained energy homeostasis and promotes cell survival in mouse skeletal muscle during cold exposure.
Assuntos
Hipotermia , Interleucina-6 , N-Acetilglucosaminiltransferases/metabolismo , Animais , Humanos , Interleucina-6/genética , Camundongos , Músculo Esquelético/metabolismo , N-Acetilglucosaminiltransferases/genéticaRESUMO
Cold stress disturbs cellular metabolic and energy homeostasis, which is one of the causes of stress-induced illnesses. O-GlcNAcylation is a nutrient-sensing pathway involved in a myriad of cellular processes. It plays a key role in metabolic homeostasis. Nevertheless, a specific sensing mechanism linking skeletal muscle to O-GlcNAcylation in cold stress is unknown. In this study, O-GlcNAcylation of SIRT1 was targeted to explore the mechanism of skeletal muscle adaptation to cold stress. Ogt mKO aggravated skeletal muscle fibrosis induced by cold stress. At the same time, Ogt gene deletion accelerated the homeostasis imbalance and oxidative stress of skeletal muscle mitochondria induced by cold stress. In vitro results showed that inhibition of SIRT1's O-GlcNAcylation accelerated mild hypothermia induced mitochondrial homeostasis in mouse myogenic cells (C2C12 cells). However, overexpression of SIRT1's O-GlcNAcylation improved the above phenomena. Thus, these results reveal a protective role of OGT-SIRT1 in skeletal muscle's adaptation to cold stress, and our findings will provide new avenues to combat stress-induced diseases.
Assuntos
Resposta ao Choque Frio , Desenvolvimento Muscular , Camundongos , Animais , Desenvolvimento Muscular/fisiologia , Homeostase , Músculo Esquelético/metabolismo , Mitocôndrias/metabolismo , N-Acetilglucosaminiltransferases/metabolismo , Sirtuína 1/genética , Sirtuína 1/metabolismoRESUMO
Procyanidin B2 (PB2), a naturally occurring flavonoid abundant in a wide range of fruits, has been shown to exert antioxidant, anti-inflammatory and anticancer properties. However, the role of PB2 in the prevention of cold stimulation (CS)-induced liver injury. The present study was undertaken to determine the effects of PB2 on liver injury induced by cold stimulation and its potential molecular mechanisms. The present study results showed that treatment with PB2 significantly reduced CS-induced liver injury by alleviating histopathological changes and serum levels of alanine transaminase and aspartate transaminase. Moreover, treatment with PB2 inhibited secretion of inflammatory cytokines and oxidative stress in cold-stimulated mice. PB2 reduced cold stimulation-induced inflammation by inhibiting TLR4/NF-κB and Txnip/NLRP3 signalling. Treatment with PB2 reduced oxidative stress by activating Nrf-2/Keap1, AMPK/GSK3ß signalling pathways and autophagy. Furthermore, simultaneous application of Shh pathway inhibitor cyclopamine proved that PB2 targets the Hh pathway. More importantly, co-treatment with PB2 and cyclopamine showed better efficacy than monotherapy. In conclusion, our findings provide new evidence that PB2 has protective potential against CS-induced liver injury, which might be closely linked to the inhibition of Shh signalling pathway.
Assuntos
Autofagia , Biflavonoides/farmacologia , Catequina/farmacologia , Temperatura Baixa , Proteínas Hedgehog/metabolismo , Fígado/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Proantocianidinas/farmacologia , Animais , Modelos Animais de Doenças , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transdução de SinaisRESUMO
Cold stress is one of the serious factors restricting the development of animal husbandry in cold areas. Cold exposure can easily lead to cold stress, slow growth and even death of newborn animals. O-GlcNAcylation modification can act as type of "stress receptor" and"nutrition sensor" in a variety of stress responses, however, it is not clear how O-GlcNAcylation can regulate glucose metabolism in the liver of piglets under cold stress. In this study, piglets 21 days of age were exposed to 4 °C for 4 h or 8 h in a phytotron. Serum cortisol and other stress hormones were used to assess body status to establish a cold stress piglet model. The changes of glycogen in liver were detected by PAS. FDP and PA were also measured to study the glycolysis level of liver. To characterize potential mechanisms of O-GlcNAcylation on the livers of cold stress piglets, AKT, GSK3ß, GS, PFKFB2, AS160 and their corresponding phosphorylation were determined by Western blotting. Results show O-GlcNAcylation increased and apoptosis levels increased in the liver following cold exposure during excessive CORT or metabolic dysfunction. It is suggested that the acute cold exposure of piglets induced a sequential change in the level of O-GlcNAcylation, which may be one of the factors mediating liver cell apoptosis and glucose metabolism regulation by the O-GlcNAc/AKT pathway. These findings provide new insight into the mechanisms of the cold stress response, which can facilitate the development of new strategies to combat the effects of hypothermia.
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Resposta ao Choque Frio , Proteínas Proto-Oncogênicas c-akt , Animais , Apoptose , Criopreservação/métodos , Glucose , Fígado , SuínosRESUMO
miRNAs are a class of small non-coding RNAs that are involved in various biological processes. In the preliminary work of the laboratory, found that miR-383-5p was down-regulated in the liver tissue of acute cold stress rats and has been shown to be an important regulatory factor in tumour proliferation, but there are very few studies involving the mediation of cold stress in rat liver tissues. Therefore, the purpose of this study was to determine the effect of miR-383-5p on the livers of cold stress rats by simulating the cold stress state of rat liver tissues in vitro using H2 O2 to induce rat hepatocyte oxidative stress. The results showed that MDA content, Caspase 3 and Cyto C protein levels increased significantly; GPx activity and SOD1 protein levels decreased significantly and miR-383-5p expression was significantly down-regulated in rat liver tissues after cold stress. Different concentrations of H2 O2 was added to rat hepatocytes, and the results showed that the expression of miR-383-5p, the ROS level, and the apoptosis rate in rat hepatocytes was increased significantly in a concentration-dependent fashion. Transfection of miR-383-5p inhibitor revealed that the apoptosis rate of rat hepatocytes, and the protein level of apoptosis-related protein Caspase 3 were reduced; the results of the dual-luciferase reporter gene assay showed that miR-383-5p targeted regulation of Bcl2. The results suggested that the expression of miR-383-5p was up-regulated in oxidative stress rat hepatocytes and may aggravate the apoptosis of rat hepatocytes induced by targeting inhibition of Bcl2 translation.
Assuntos
Apoptose , MicroRNAs , Estresse Oxidativo , Animais , Regulação para Baixo , Hepatócitos/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RatosRESUMO
The Zi goose is native to North-east China and is noted for its high egg production. Alpha enolase (ENO1) is a glycolytic enzyme which functions as a plasminogen receptor in follicular granulosa cells (FGCs), with several studies showing that FGCs can support follicular development. By transfecting the ENO1 interfering plasmid (shRNA) into FGCs, ENO1 expression in these cells was downregulated, suggesting the successful knock-down of ENO1 in these cells. In this knock-down model, we detected 13 metabolites from FGCs using LC/MS. When compared with the non-coding shRNA (NC) group, the lower level metabolites were (R)-(+)-citronellic acid, altretamine, 3-hydroxycaproic acid, heptadecanoic acid, cholecalciferol vitamin D3, indole, benzoic acid, capric acid, caffeic acid, azelaic acid, 3,4-dihydroxyhydrocinnamic acid and cholic acid, while oleic acid was detected at high levels. To further examine the results of metabolomics, six key metabolites were verified by gas chromatography-mass spectrometry (GC-MS). We found that vitamin D3, indole, benzoic acid, capric acid and cholic acid were significantly downregulated in the shRNA group, while oleic acid was significantly upregulated. This observation was consistent with the metabolomics data. Through these studies, we found that decreased ENO1 levels altered certain metabolite levels in FGCs.
Assuntos
Proteínas de Ligação a DNA/metabolismo , Gansos/fisiologia , Regulação Enzimológica da Expressão Gênica/fisiologia , Células da Granulosa/metabolismo , Fosfopiruvato Hidratase/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Animais , Células Cultivadas , Proteínas de Ligação a DNA/genética , Feminino , Humanos , Redes e Vias Metabólicas , Fosfopiruvato Hidratase/genética , Análise de Componente Principal , Interferência de RNA , RNA Interferente Pequeno , Proteínas Supressoras de Tumor/genéticaRESUMO
Stress induces many different sex-specific physiological and psychological responses during adolescence. Although the impact of certain brain stressors has been reported in the literature, the influence of cold stress on the mechanisms underlying hippocampal neurotransmitter disorder and neuroinflammation remain unstudied. Adolescent male and female C57BL/6 mice were exposed to 4⯰C temperatures, 3â¯h per day for 1â¯week. Serum CORT and blood gas analysis was then used to assess body status. Using western blotting, immunofluorescence and immunohistochemistry we also assessed glial cell number and microglial activation, as well as inflammatory cytokine levels and related protein expression levels. The phenomena of excessive CORT, microglial activation, increased acetylate-HMGB1 levels, NF-κB signaling pathway activation, pro-inflammatory cytokine release, neuronal apoptosis and neurotransmitter disorder were demonstrated in mouse hippocampal tissue following cold exposure. We believe that these phenomena are mediated by the HMGB1/TLR4/NFκB pathway. Finally, the male inflammatory response in hippocampal tissue was more severe and the influence of cold exposure on neurotransmitter was greater in females.
Assuntos
Proteína HMGB1/metabolismo , Hipocampo/metabolismo , Neurotransmissores/metabolismo , Fatores Etários , Animais , Apoptose/fisiologia , Temperatura Baixa , Citocinas/metabolismo , Feminino , Inflamação/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/metabolismo , NF-kappa B/metabolismo , Neuroglia/metabolismo , Neuroimunomodulação , Neurônios/metabolismo , Fatores Sexuais , Transdução de Sinais/fisiologia , Estresse Fisiológico/fisiologia , Lobo Temporal/metabolismo , Receptor 4 Toll-Like/metabolismoRESUMO
At low temperatures, the liver increases glucose utilization and expresses RNA-binding motif 3 (RBM3) to cope with cold exposure. In this study, the expression of heat shock protein 70 (HSP70), Toll-like receptor 4 (TLR4), bone marrow differentiation factor 88 (MYD88), and phosphorylated nuclear factor-κB (NF-κB) was consistent with fluctuations in insulin in fasted cold-exposed mice. We also found up-regulation of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) in acute cold exposure with a decrease in core body temperature. RBM3 transcription and translation were activated 2 h after cold exposure. The anti-apoptotic factor Bcl-2/Bax ratio also increased, while expression of apoptosis factors: cleaved caspase-3, cleaved poly(ADP-ribose)polymerase 1 (PARP-1) and cytochrome-c (Cyt-c) was unchanged. Liver glycogen was depleted after 2 h of cold exposure, and blood glucose decreased after 4 h. Glycogen synthase kinase 3ß (GSK3ß) phosphorylation continued to increase to promote hepatic glycogen synthesis. We found a high level of protein kinase B (AKT) phosphorylation after 6 h of cold exposure. In addition, we demonstrated that after cold exposure for 2 h, in the liver, continued phosphorylation of fructose-2,6-diphosphate (PFKFB2) and decreased accumulation of glycogen intermediates fructose-1,6-diphosphate (FDP) and pyruvic acid (PA). In summary, the liver responds to cold exposure through a number of different pathways, including activation of HSP70/TLR4 signaling pathways, up-regulation of RBM3 expression, and increased glycolysis and glycogen synthesis. We propose a possible signaling pathway in which regulation of RBM3 expression by the liver affects the AKT metabolic signaling pathway. Lay summary In response to changes in ambient temperature, mice regulate global metabolism and gene expression through hormones. This study focused on the effects of environmental hypothermia on molecular pathways of glucose metabolism in the liver, which is the important metabolic organ in mice. This provides a basis for further study of mice against cold exposure damage.
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Glicólise/fisiologia , Fígado/metabolismo , Motivos de Ligação ao RNA , Receptor 4 Toll-Like/metabolismo , Animais , Apoptose , Glicemia/metabolismo , Glucose/metabolismo , Glicogênio/metabolismo , Insulina/sangue , Camundongos , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Transdução de Sinais/fisiologia , Estresse PsicológicoRESUMO
Quinalizarin, a bioactive and highly selective compound, is known to promote apoptosis in colon and lung cancer cells. However, studies evaluating quinalizarin-induced apoptosis in melanoma cells have not been conducted. In the present study, we investigated the underlying mechanisms of antimelanoma activity of quinalizarin in human melanoma A375 cells. The MTT assay and Trypan blue staining were used to evaluate the cell viability. The flow cytometry was used to detect cell cycle, apoptosis and reactive oxygen species (ROS). Western blot was used to detect the expression of cell cycle and apoptosis-related proteins, MAPK, and STAT3. The results revealed a significant dose and time dependent effect of quinalizarin on inhibiting proliferation in three kinds of human melanoma cells, and had no significant toxic effects on normal cells. Moreover, quinalizarin triggered G2/M phase cell arrest by modulating the protein expression levels of CDK 1/2, cyclin A, cyclin B, p21 and p27, and induced apoptosis by down-regulating the antiapoptotic protein Bcl-2 and upregulating the proapoptotic protein BAD, leading to the activation of caspase-3 and PARP in the caspase cascade in A375 cells. Quinalizarin treatment led to apoptosis of A375 cells via activation of MAPK and inhibition of STAT3 signaling pathways. In addition, quinalizarin increased the level of ROS, but ROS scavenger NAC inhibited quinalizarin-induced apoptosis by regulating MAPK and STAT3 signaling pathways. In summary, quinalizarin induces cell cycle arrest and apoptosis via ROS-mediated MAPK and STAT3 signaling pathways in human melanoma A375 cells, and quinalizarin may be used as a novel and effective antimelanoma therapeutic.
Assuntos
Antraquinonas/farmacologia , Melanoma/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Melanoma/tratamento farmacológico , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
Cold-inducible RNA-binding protein (CIRP) is a stress-responsive protein involved in several signal transduction pathways required for cellular function, which are associated with apoptosis and proliferation. The present study aimed to investigate the possible effects of CIRP-mediated regulation of glucose metabolism in the liver following acute cold exposure. The livers and serum of male C57BL/6 mice were collected following cold exposure at 4 °C for 0 h, 2 h, 4 h, and 6 h. Glucose metabolic markers and the expression of glucose metabolic-related proteins were detected in the liver. Acute cold exposure was found to increase the consumption of glycogen in the liver. Fructose-1,6-diphosphate (FDP) and pyruvic acid (PA) were found to show a brief increase followed by a sharp decrease during cold exposure. Anti-apoptotic protein (Bcl-2) expression was upregulated. CIRP protein expression displayed a sequential increase with prolonged acute cold exposure time. Acute cold exposure also increased the level of protein kinase B (AKT) phosphorylation, and activated the AKT-signaling pathway. Taken together, these findings indicate that acute cold exposure increased the expression of CIRP protein, which regulates mouse hepatic glucose metabolism and maintains hepatocyte energy balance through the AKT signaling pathway, thereby slowing the liver cell apoptosis caused by cold exposure.
Assuntos
Temperatura Baixa , Glicólise , Fígado/metabolismo , Proteínas de Ligação a RNA/genética , Animais , Apoptose/genética , Glicemia , Regulação da Expressão Gênica , Inativação Gênica , Glucagon/sangue , Glucose/metabolismo , Glicogênio/metabolismo , Insulina/sangue , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas de Ligação a RNA/metabolismo , Transdução de SinaisRESUMO
MicroRNAs (miRNAs) are a class of single-stranded non-coding small RNA molecules, which participate in the regulation of many physiological processes, and play a crucial role in cancer, metabolism and other processes. Rno-miR-425-5p has been shown to play a role in the response to cold stress. To explore the mechanism by which rno-miR-425-5p regulates the response to cold stress, we analysed the candidate target genes of rno-miR-425-5p. After verification in rat hepatocyte BRL cells and in rat liver tissue, we identified several target genes that were altered in expression in response to cold stress. In rat liver tissue, the expression of rno-miR-425-5p was significantly increased and the expression levels of target genes DLST and SLC16A1 were decreased under cold stress. The miRNA and mRNA levels were analysed by quantitative real-time PCR and the protein levels were detected by Western blot analysis. Combined with the results of bioinformatic analysis, we concluded that rno-miR-425-5p reduced the expression of DLST and SLC16A1, inhibiting energy release from the tricarboxylic acid cycle and preventing the liver from being injured by excessive energy mobilization.
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Aciltransferases/metabolismo , Temperatura Baixa , MicroRNAs/genética , Transportadores de Ácidos Monocarboxílicos/metabolismo , Estresse Fisiológico , Simportadores/metabolismo , Aciltransferases/genética , Animais , Linhagem Celular , Resposta ao Choque Frio , Biologia Computacional , Metabolismo Energético , Regulação da Expressão Gênica , Hepatócitos/fisiologia , Ciência dos Animais de Laboratório , Hepatopatias , Masculino , Transportadores de Ácidos Monocarboxílicos/genética , Distribuição Aleatória , Ratos , Organismos Livres de Patógenos Específicos , Simportadores/genéticaRESUMO
Routine coagulation test before intravenous tissue plasminogen activator (tPA) use increases the door to needle time (DNT). We sought to evaluate the safety of tPA use without coagulation results and its impact on prognosis. In our stroke registry, tPA was delivered with coagulation results from December 2015 to April 2016 and without coagulation results from May 2016 to December 2016. Differences of demographics, clinical characteristic, and prognosis between these two groups were analyzed. In addition, logistic regression analysis was conducted to identify predictors for DNT of over 60 min. A total of 201 stroke patients were included in the final analysis. Of these, 81 patients received tPA with coagulation results and 120 patients without coagulation results. Only one (0.8%) patient with abnormal coagulation results met the exclusion criteria of tPA use in patients without coagulation results. The difference of DNT between groups with (mean, 61.7 min) and without (mean, 41.9 min) coagulation results was significant (P = 0.00). The group without coagulation results had a higher rate of favorable 90-day outcome (74.2 vs 70.4%) and lower rates of symptomatic intracranial hemorrhage/nonintracranial hemorrhage (4.9 and 22.2% vs 1.7 and 19.2%) than the group with coagulation results did; these differences were not statistically significant. In multivariate analysis, only tPA use with coagulation results was the predictor for DNT of over 60 min (P = 0.0030, OR = 2.44, 95% CI 1.28-4.65). The present study suggests that tPA could be delivered safely without coagulation results in patients without suspected coagulopathy, and avoiding coagulation tests reduces significantly the DNT interval.
Assuntos
Isquemia Encefálica/sangue , Isquemia Encefálica/tratamento farmacológico , Fibrinolíticos/administração & dosagem , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/tratamento farmacológico , Ativador de Plasminogênio Tecidual/administração & dosagem , Administração Intravenosa , Adulto , Idoso , Idoso de 80 Anos ou mais , Testes de Coagulação Sanguínea , Isquemia Encefálica/diagnóstico , China , Feminino , Fibrinolíticos/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Sistema de Registros , Estudos Retrospectivos , Acidente Vascular Cerebral/diagnóstico , Tempo para o Tratamento , Ativador de Plasminogênio Tecidual/efeitos adversos , Resultado do TratamentoRESUMO
Protein O-linked ß-N-acetylglucosamine glycosylation (O-GlcNAcylation) regulates many biological processes. Studies have shown that O-GlcNAc modification levels can increase during acute stress and suggested that this may contribute to the survival of the cell. This study investigated the possible effects of O-GlcNAcylation that regulate glucose metabolism, apoptosis, and autophagy in the liver after acute cold stress. Male C57BL/6 mice were exposed to cold conditions (4 °C) for 0, 2, 4, and 6 h, then their livers were extracted and the expression of proteins involved in glucose metabolism, apoptosis, and autophagy was determined. It was found that acute cold stress increased global O-GlcNAcylation and protein kinase B (AKT) phosphorylation levels. This was accompanied by significantly increased activation levels of the glucose metabolism regulators 160 kDa AKT substrate (AS160), 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 2 (PFKFB2), and glycogen synthase kinase-3ß (GSK3ß). The levels of glycolytic intermediates, fructose-1,6-diphosphate (FDP) and pyruvic acid (PA), were found to show a brief increase followed by a sharp decrease. Additionally, adenosine triphosphate (ATP), as the main cellular energy source, had a sharp increase. Furthermore, the B-cell lymphoma 2(Bcl-2)/Bcl-2-associated X (Bax) ratio was found to increase, whereas cysteine-aspartic acid protease 3 (caspase-3) and light chain 3-II (LC3-II) levels were reduced after acute cold stress. Therefore, acute cold stress was found to increase O-GlcNAc modification levels, which may have resulted in the decrease of the essential processes of apoptosis and autophagy, promoting cell survival, while altering glycose transport, glycogen synthesis, and glycolysis in the liver.
Assuntos
Acetilglucosamina/metabolismo , Apoptose , Autofagia , Resposta ao Choque Frio , Fígado/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Glicemia/análise , Glicemia/metabolismo , Frutosedifosfatos/metabolismo , Glucagon/sangue , Glucagon/metabolismo , Glucose/metabolismo , Glicogênio/metabolismo , Glicosilação , Insulina/sangue , Insulina/metabolismo , Fígado/citologia , Masculino , Camundongos Endogâmicos C57BL , N-Acetilglucosaminiltransferases/metabolismo , Ácido Pirúvico/metabolismoRESUMO
miRNA is an endogenously noncoding sRNA, which is involved in post-transcription gene expression regulation of growth, tumor development and stress survival. As a biological marker, miRNA has been used for the early diagnosis of diseases and the evaluation of some physiological state. We constructed two small RNA libraries with the serums of rats treated or not with cold conditions (4â for 12h) by deep sequencing, in order to understand the miRNAs' expressions of cold-exposed rats and find new cold-responsive biological markers. 485 conserved miRNAs and 287 novel miRNAs were identified in the two libraries by comparing to the known miRNAs of rat in miRBase 21.0 Differential expression analysis showed that 56 conserved miRNAs and 3 novel miRNAs were expressed differentially in low ambient temperature. The qRT-PCR results confirmed that rno-miR-151-3p, rno-miR-210-3p, rno-miR-425-5p, rno-miR-383-5p, rno-miR-92a-3p, rno-miR-98-5p and rno-miR-328a-3p decreased significantly in rats serums treated with cold exposure. The expressions of the 7 miRNAs changed significantly in cold-exposed rats' livers too. rno-miR-383-5p decreased significantly, but all the others increased significantly. Thus, the 7 miRNAs were considered as cold-responsive miRNAs of rat. 670 target genes of the 7 cold-responsive miRNAs were predicted. KEGG analysis showed that they were enriched in 28 pathways and most of them were enriched by metabolic pathway. Overall, the results of this study suggest an important role for selected miRNA's in the response to cold stress.
Assuntos
Temperatura Baixa , MicroRNAs/genética , Estresse Fisiológico/genética , Animais , Sequenciamento de Nucleotídeos em Larga Escala , MicroRNAs/metabolismo , RatosRESUMO
BACKGROUND: Whether nonintracranial hemorrhage (NICH) associated with intravenous thrombolysis (IVT) is a predictor of intracranial hemorrhage (ICH) and poor prognosis is ambiguous. We sought to analyze the rate of NICH and the relationship between NICH and poor outcome in the ischemic stroke population undergoing IVT. METHODS: This is a single-center, hospital-based prospective study. All ischemic stroke patients undergoing IVT between December 2015 and November 2016 were included. NICH was defined according to the criteria of the Bleeding Academic Research Consortium (BARC). ICH associated with IVT was defined based on the European Cooperative Acute Stroke Study II definition. On the basis of the modified Rankin Scale (mRS), 90-day outcome was divided into favorable outcome (mRS score 0-1) versus unfavorable outcome (mRS score 2-6) and independency (mRS score 0-2) versus dependency and death (mRS score 3-6). RESULTS: A total of 212 patients undergoing IVT were included in the analysis. Forty-five NICH events were reported in 42 patients (19.8%). Older age was independently associated with NICH (P = .049, odds ratio [OR] = .97, 95% confidence interval [CI] .94-1.0). Neither NICH with BARC class 1 or higher (P = .56, OR = .61, 95% CI .11-3.24) nor NICH with BARC class 2 or higher (P = .87, OR = 1.19, 95% CI .14-10.23) was associated with ICH. NICH with BARC class 1 or higher was not associated with unfavorable outcome (P = .67, OR = 1.17, 95% CI .56-2.45) and dependence and death (P = .47, OR = .72, 95% CI .30-1.75), neither was NICH with BARC class 2 or higher (P = .97, OR = 1.02, 95% CI .46-2.27 and P = .30, OR = .59, 95% CI .22-1.62). CONCLUSIONS: NICH was common among ischemic stroke populations receiving IVT. NICH with BARC class 2 or lower was not associated with ICH and poor outcome.