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Objectives: This study investigates the role of Nicotinamide N-methyltransferase (NNMT) in immune infiltration modulation through amino acid metabolism in gastric adenocarcinoma (STAD). Methods: Utilizing data from The Cancer Genome Atlas (TCGA) and validated with clinical samples, we analyzed NNMT expression and its prognostic implications in STAD. Differential amino acid profiles between cancerous and adjacent normal tissues were assessed, along with their associations with NNMT. Results: NNMT exhibits heightened expression in STAD cancer tissues, positively correlating with tumor immune infiltration. Additionally, twenty-eight amino acids display differential expression in gastric tissue, with their metabolic enzymes showing connections to NNMT. Conclusions: Elevated NNMT expression in STAD tissues potentially influences amino acid metabolism, thereby affecting immune infiltration dynamics and tumorigenesis in gastric adenocarcinoma.
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Adenocarcinoma , Aminoácidos , Nicotinamida N-Metiltransferasa , Neoplasias Gástricas , Nicotinamida N-Metiltransferasa/metabolismo , Nicotinamida N-Metiltransferasa/genética , Humanos , Neoplasias Gástricas/inmunología , Neoplasias Gástricas/patología , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/patología , Adenocarcinoma/inmunología , Adenocarcinoma/metabolismo , Aminoácidos/metabolismo , Pronóstico , Masculino , Femenino , Regulación Neoplásica de la Expresión Génica , Persona de Mediana EdadRESUMEN
Microglia, the resident immune cells of the central nervous system (CNS), play a dual role in neurotoxicity by releasing the NLR Family Pyrin Domain Containing 3 (NLRP3) inflammasome and brain-derived neurotrophic factor (BDNF) in response to environmental stress. Suppression of BDNF is implicated in learning and memory impairment induced by exposure to manganese (Mn) or lead (Pb) individually. Methyl CpG Binding Protein 2 (MeCp2) and its phosphorylation status are related to BDNF suppression. Protein phosphatase2A (PP2A), a member of the serine/threonine phosphatases family, dephosphorylates substrates based on the methylation state of its catalytic C subunit (PP2Ac). However, the specific impairment patterns and molecular mechanisms resulting from co-exposure to Mn and Pb remain unclear. Therefore, the purpose of this study was to explore the effects of Mn and Pb exposure, alone and in combination, on inducing neurotoxicity in the hippocampus of mice and BV2 cells, and to determine whether simultaneous exposure to both metals exacerbate their toxicity. Our findings reveal that co-exposure to Mn and Pb leads to severe learning and memory impairment in mice, which correlates with the accumulation of metals in the hippocampus and synergistic suppression of BDNF. This suppression is accompanied by up-regulation of the epigenetic repressor MeCp2 and its phosphorylation status, as well as demethylation of PP2Ac. Furthermore, inhibition of PP2Ac demethylation using ABL127, an inhibitor for its protein phosphatase methylesterase1 (PME1), or knockdown of MeCp2 via siRNA transfection in vitro effectively increases BDNF expression and mitigates BV2 cell damage induced by Mn and Pb co-exposure. We also observe abnormal activation of microglia characterized by enhanced release of the NLRP3 inflammasome, Casepase-1 and pro-inflammatory cytokines IL-1ß, in the hippocampus of mice and BV2 cells. In summary, our experiments demonstrate that simultaneous exposure to Mn and Pb results in more severe hippocampus-dependent learning and memory impairment, which is attributed to epigenetic suppression of BDNF mediated by PP2A regulation.
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Factor Neurotrófico Derivado del Encéfalo , Epigénesis Genética , Hipocampo , Plomo , Manganeso , Trastornos de la Memoria , Animales , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Ratones , Epigénesis Genética/efectos de los fármacos , Manganeso/toxicidad , Plomo/toxicidad , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Trastornos de la Memoria/inducido químicamente , Masculino , Ratones Endogámicos C57BL , Microglía/efectos de los fármacos , Proteína 2 de Unión a Metil-CpG/metabolismo , Proteína 2 de Unión a Metil-CpG/genética , Proteína Fosfatasa 2/metabolismo , Aprendizaje/efectos de los fármacosRESUMEN
Exposure to the organochlorine fungicide pentachloronitrobenzene (PCNB) causes developmental abnormalities, including cardiac malformation. However, the molecular mechanism of PCNB cardiotoxicity remains elusive. We found that oral administration of PCNB to pregnant mice induced a hypoplastic wall with significant thinning of the compact myocardium in the developing hearts. PCNB significantly downregulates the expression of Hec1, a member of the NDC80 kinetochore complex, resulting in aberrant spindles, chromosome missegregation and an arrest in cardiomyocyte proliferation. Cardiac-specific ablation of Hec1 sharply inhibits cardiomyocyte proliferation, leading to thinning of the compact myocardium and embryonic lethality. Mechanistically, we found that activating transcription factor 3 (ATF3) transactivates Hec1 expression. Either HEC1 or ATF3 overexpression significantly rescues mitotic defects and restore the decreased proliferative ability of cardiomyocytes caused by PCNB exposure. Our findings highlight that maternal PCNB exposure disrupts embryonic cardiac function by inhibiting cardiomyocyte proliferation and interfering with ventricular wall development, partially attributed to the downregulation of the Atf3-Hec1 axis.
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Miocitos Cardíacos , Nitrobencenos , Proteínas Nucleares , Animales , Ratones , Regulación hacia Abajo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proliferación CelularRESUMEN
Non-alcoholic fatty liver disease (NAFLD) is a progressive disorder of liver metabolism and has become the most common chronic liver disease worldwide. Benzo[a]pyrene (BaP) is recognized as a potent carcinogen, but the effect of low-dose BaP on the development of NAFLD has not been well-studied, and its molecular mechanism is still unknown. In this study, we demonstrated that low-dose BaP induced hepatic steatosis in a mouse model with a notable increase in hepatic lipid content. Interestingly, mRNA expression of genes related to fatty acids uptake or synthesis was not significantly altered after BaP exposure. Instead, we found that low-dose BaP promoted lipid deposition in primary mouse hepatocytes by inhibiting autophagy, which was regulated through Leucine carboxyl methyltransferase-1 (LCMT1) mediated Protein Phosphatases 2A subunit C (PP2Ac) methylation. The role of LCMT1 in BaP-induced steatosis was further validated in a liver-specific lcmt1 knockout (L-LCMT1 KO) mouse model. In this study, we provided evidence to support a novel mechanism by which BaP induces the development of hepatic steatosis through PP2Ac mediated autophagy inhibition. These findings provided new insight into the pathogenesis of NAFLD induced by environmental exposure to low-dose BaP.
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Enfermedad del Hígado Graso no Alcohólico , Animales , Ratones , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Benzo(a)pireno/metabolismo , Hígado , Fosfoproteínas Fosfatasas , Autofagia , LípidosRESUMEN
Objective To investigate the molecular mechanism of taurine regulating the polarization of M2 macrophages by mitophagy. Methods THP-1 cells were divided into four groups: M0 group (THP-1 cells were treated by 100 nmol/L phorbol myristate ester for 48 hours to polarize into M0), M2 group (THP-1 cells were induced to polarize into M2 macrophages by 20 ng/mL interferon-4 (IL-4) for 48 hours), M2 combined with taurine groups (added with 40 or 80 mmol/L taurine on the basis of M2 macrophages). The mRNA expression of mannose receptor C type 1(MRC-1), C-C motif chemokine ligand 22(CCL22) and dendritic cell-specific ICAM-3 grabbing non-integrin (CD209) in M2 macrophages were detected by quantitative real-time PCR. Mitochondrial and lysosome probes were used to detect the number of mitochondria and lysosomes by multifunction microplate reader and confocal laser scanning microscope. The level of mitochondrial membrane potential (MMP) was detected by JC-1 MMP assay kit. The expression of mitophagy-related proteins PTEN-induced putative kinase 1 (PINK1) and microtubule-associated protein 1 light chain 3 (LC3) were detected by Western blot analysis. Results Compared with M0 group, the expression of MRC-1, CCL22, CD209 and PINK1, the number of mitochondria and the level of MMP in M2 group were significantly increased, whereas the number of lysosomes and LC3II/LC3I ratio were decreased. Compared with M2 group, the expressions of MRC-1, CCL22 and CD209, the number of mitochondria and the level of MMP in M2 combined with taurine group dropped significantly while the number of lysosomes was found increased, and the protein expression of PINK1 and LC3II/LC3I ratio were also increased. Conclusions The polarization of M2 macrophages is regulated by taurine to prevent excessive polarization via reducing the level of MMP, improving the level of mitophagy, reducing the number of mitochondria, and inhibiting the mRNA expression of polarization markers in M2 macrophages.
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Mitofagia , Taurina , Macrófagos/metabolismo , Proteínas Quinasas/metabolismo , ARN MensajeroRESUMEN
Impaired glucose regulation is one of the most important risk factors for type 2 diabetes mellitus (T2DM) and cardiovascular diseases, which have become a major public health issue worldwide. Dysregulation of carbohydrate metabolism in liver has been shown to play a critical role in the development of glucose intolerance but the molecular mechanism has not yet been fully understood. In this study, we investigated the role of hepatic LCMT1 in the regulation of glucose homeostasis using a liver-specific LCMT1 knockout mouse model. The hepatocyte-specific deletion of LCMT1 significantly upregulated the hepatic glycogen synthesis and glycogen accumulation in liver. We found that the liver-specific knockout of LCMT1 improved high fat diet-induced glucose intolerance and insulin resistance. Consistently, the high fat diet-induced downregulation of glucokinase (GCK) and other important glycogen synthesis genes were reversed in LCMT1 knockout liver. In addition, the expression of GCK was significantly upregulated in MIHA cells treated with siRNA targeting LCMT1 and improved glycogen synthesis. In this study, we provided evidences to support the role of hepatic LCMT1 in the development of glucose intolerance induced by high fat diet and demonstrated that inhibiting LCMT1 could be a novel therapeutic strategy for the treatment of glucose metabolism disorders.
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Diabetes Mellitus Tipo 2 , Intolerancia a la Glucosa , Resistencia a la Insulina , Proteína O-Metiltransferasa , Ratones , Animales , Intolerancia a la Glucosa/etiología , Intolerancia a la Glucosa/metabolismo , Dieta Alta en Grasa/efectos adversos , Leucina/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Hígado/metabolismo , Glucosa/metabolismo , Glucógeno/metabolismo , Metiltransferasas/metabolismo , Proteína O-Metiltransferasa/metabolismoRESUMEN
BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most malignant type of cancers. Leuci carboxyl methyltransferase 1 (LCMT1) is a protein methyltransferase that plays an improtant regulatory role in both normal and cancer cells. The aim of this study is to evaluate the expression pattern and clinical significance of LCMT1 in HCC. METHODS: The expression pattern and clinical relevance of LCMT1 were determined using the Gene Expression Omnibus (GEO) database, the Cancer Genome Atlas (TCGA) program, and our datasets. Gain-of-function and loss-of-function studies were employed to investigate the cellular functions of LCMT1 in vitro and in vivo. Quantitative real-time polymerase chain reaction (RT-PCR) analysis, western blotting, enzymatic assay, and high-performance liquid chromatography were applied to reveal the underlying molecular functions of LCMT1. RESULTS: LCMT1 was upregulated in human HCC tissues, which correlated with a "poor" prognosis. The siRNA-mediated knockdown of LCMT1 inhibited glycolysis, promoted mitochondrial dysfunction, and increased intracellular pyruvate levels by upregulating the expression of alani-neglyoxylate and serine-pyruvate aminotransferase (AGXT). The overexpression of LCMT1 showed the opposite results. Silencing LCMT1 inhibited the proliferation of HCC cells in vitro and reduced the growth of tumor xenografts in mice. Mechanistically, the effect of LCMT1 on the proliferation of HCC cells was partially dependent on PP2A. CONCLUSIONS: Our data revealed a novel role of LCMT1 in the proliferation of HCC cells. In addition, we provided novel insights into the effects of glycolysis-related pathways on the LCMT1regulated progression of HCC, suggesting LCMT1 as a novel therapeutic target for HCC therapy.
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Doxorubicin (DOX) is a widely used anticancer drug, but its clinical application is limited by cardiotoxicity. As a member of the Rab family, Rab10 has multiple subcellular localizations and carries out a wide variety of functions. Here, we explored the role of Rab10 on DOX-induced cardiotoxicity. Cardiac-specific Rab10 transgenic mice were constructed and treated with DOX or saline. We found that cardiac-specific overexpression of Rab10 alleviated cardiac dysfunction and attenuated cytoplasmic vacuolization and mitochondrial damage in DOX-treated mouse heart tissues. Immunofluorescence staining and Western blot analysis showed that Rab10 alleviated DOX-induced apoptosis and oxidative stress in cardiomyocytes in mouse heart tissues. We demonstrated that DOX mediated apoptosis, oxidative stress and depolarization of the mitochondrial membrane potential in H9c2 cells, while overexpression and knockdown of Rab10 attenuated and aggravated these effects, respectively. Furthermore, we found that Mst1, a serine-threonine kinase, was cleaved and translocated into the nucleus in H9c2 cells after DOX treatment, and knockdown of Mst1 alleviated DOX-induced cardiomyocyte apoptosis. Overexpression of Rab10 inhibited the cleavage of Mst1 mediated by DOX treatment in vivo and in vitro. Together, our findings demonstrated that cardiac-specific overexpression of Rab10 alleviated DOX-induced cardiac dysfunction and injury via inhibiting oxidative stress and apoptosis of cardiomyocytes, which may be partially ascribed to the inhibition of Mst1 activity.
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Cardiotoxicidad , Cardiopatías , Proteínas de Unión al GTP rab , Animales , Ratones , Apoptosis , Doxorrubicina/toxicidad , Cardiopatías/metabolismo , Miocitos Cardíacos , Estrés Oxidativo , Proteínas de Unión al GTP rab/genética , Proteínas de Unión al GTP rab/metabolismoRESUMEN
[This retracts the article DOI: 10.3892/ol.2015.4001.].
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Manganese (Mn) exposure leads to autophagy dysfunction and causes neurodegenerative diseases such as Parkinson's syndrome and Alzheimer's disease. However, the mechanism of neurotoxicity of Mn has been less clear. The methylation of the protein phosphatase 2A catalytic subunit determines the dephosphorylation activity of protein phosphatase and plays an important role in autophagy regulation. In this investigation, we established a model of Mn (0-2000 µmol/L) exposure to N2a cells for 12 h, used the PPME-1 inhibitor ABL-127, and constructed an LCMT1-overexpressing N2a cell line. We also regulated the PP2Ac methylation level and explored the effect of PP2Ac methylation on Mn-induced (0-1000 µmol/L) N2a cellular autophagy. Our results showed that Mn > 500 µmol/L induced N2a cell damage and increased oxidative stress. Moreover, Mn modulated autophagy in N2a cells by downregulating PP2Ac methylation, which regulated mTORC1 signaling pathway activation. Both ABL-127 and LCMT1 overexpression can upregulate PP2Ac methylation in parallel with ameliorating N2a cell abnormal autophagy induced by Mn, Briefly, the upregulation of PP2Ac methylation can ameliorate the autophagy disorder of N2a by Mn and effectively alleviate Mn-induced cytotoxicity and oxidative stress, indicating that regulation of autophagy is a protective strategy against Mn-induced neurotoxicity.
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Homólogo de la Proteína 1 Relacionada con la Autofagia/metabolismo , Autofagia , Manganeso/toxicidad , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Proteína Fosfatasa 2/metabolismo , Animales , Autofagia/efectos de los fármacos , Línea Celular Tumoral , Metilación , Ratones , Estrés Oxidativo/efectos de los fármacosRESUMEN
Excessive exposure to manganese (Mn) can cause cognitive impairment, a common feature of Alzheimer's disease (AD), but the mechanisms remain unclear. Amyloid precursor protein (APP) is key to AD pathogenesis, and whether APP and its secretase processing are involved in Mn-induced cognitive impairment remains unknown. In the present study, we established a model of Mn-induced neurotoxicity in vivo (male C57BL/6, 0-100 mg/kg Mn, 90 days, gastric gavage) and in vitro (Neuro-2a (N2a) cells, 0-800 µM Mn for 24 h; APP overexpression and APP shRNA N2a cells, 0 and 800 µM Mn for 24 h). We found impaired cognition of Mn-treated mice. Both in vivo and in vitro results consistently showed that Mn exposure inhibited the expression of APP, α-secretase, soluble APP alpha protein (sAPPα), and synapse proteins as well as the activity of α-secretase. However, Mn exposure showed no effect on the protein levels of ß-secretase, Aß40, and Aß42 or the activity of ß-secretase. Collectively, these findings demonstrate key roles of APP and its α-secretase processing in the regulation of Mn-induced cognitive impairment, which may act as a target for ameliorating Mn-induced neurotoxicity.
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Secretasas de la Proteína Precursora del Amiloide/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Disfunción Cognitiva/inducido químicamente , Manganeso/toxicidad , Secretasas de la Proteína Precursora del Amiloide/genética , Precursor de Proteína beta-Amiloide/genética , Animales , Línea Celular , Disfunción Cognitiva/metabolismo , Disfunción Cognitiva/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Sinapsis/efectos de los fármacos , Sinapsis/metabolismo , Sinapsis/patologíaRESUMEN
The excessive M1 polarization of macrophages drives the occurrence and development of inflammatory diseases. The reprogramming of macrophages from M1 to M2 can be achieved by targeting metabolic events. Taurine promotes for the balance of energy metabolism and the repair of inflammatory injury, preventing chronic diseases and complications. However, little is known about the mechanisms underlying the action of taurine modulating the macrophage polarization phenotype. In this study, we constructed a low-dose LPS/IFN-γ-induced M1 polarization model to simulate a low-grade pro-inflammatory process. Our results indicate that the taurine transporter TauT/SlC6A6 is upregulated at the transcriptional level during M1 macrophage polarization. The nutrient uptake signal on the membrane supports the high abundance of taurine in macrophages after taurine supplementation, which weakens the status of methionine metabolism, resulting in insufficient S-adenosylmethionine (SAM). The low availability of SAM is directly sensed by LCMT-1 and PME-1, hindering PP2Ac methylation. PP2Ac methylation was found to be necessary for M1 polarization, including the positive regulation of VDAC1 and PINK1. Furthermore, its activation was found to promote the elimination of mitochondria by macrophages via the mitophagy pathway for metabolic adaptation. Mechanistically, taurine inhibits SAM-dependent PP2Ac methylation to block PINK1-mediated mitophagy flux, thereby maintaining a high mitochondrial density, which ultimately hinders the conversion of energy metabolism to glycolysis required for M1. Our findings reveal a novel mechanism of taurine-coupled M1 macrophage energy metabolism, providing novel insights into the occurrence and prevention of low-grade inflammation, and propose that the sensing of taurine and SAM availability may allow communication to inflammatory response in macrophages.
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Glucólisis/efectos de los fármacos , Activación de Macrófagos/efectos de los fármacos , Macrófagos/efectos de los fármacos , Mitofagia/efectos de los fármacos , Proteína Fosfatasa 2/metabolismo , S-Adenosilmetionina/metabolismo , Taurina/farmacología , Expresión Génica/efectos de los fármacos , Humanos , Interferón gamma/farmacología , Lipopolisacáridos/farmacología , Activación de Macrófagos/inmunología , Macrófagos/clasificación , Macrófagos/inmunología , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , Metilación/efectos de los fármacos , Proteínas Quinasas/genética , Proteínas Quinasas/metabolismo , Células THP-1 , Taurina/metabolismo , Canal Aniónico 1 Dependiente del Voltaje/genética , Canal Aniónico 1 Dependiente del Voltaje/metabolismoRESUMEN
PURPOSE: This study aims to investigate the application value of O-arm navigation system in sacroiliac screw placement for the treatment of unstable pelvic ring injury. METHODS: A total of 40 patients (mean age = 30.75 ± 14.99 years, 25 males, 15 females) were included. From January 2016 to July 2018, 40 patients with posterior pelvic ring injury treated in our hospital were included. Of them, 19 patients underwent O-arm navigation for screw placement (O-arm group) while the other 21 received C-arm fluoroscopy guidance (C-arm group) for sacroiliac screw placement. Intraoperative outcomes and the outcome of screw placement were compared between groups. The quality of radiological images was assessed by Matta's radiological outcome grade. The outcome of complex pelvic fracture treatment was evaluated by Majeed Functional score. RESULTS: All demographic and clinical characteristics were comparable between the two groups. Compared with the C-arm groups, the O-arm group had a shorter surgery time (33.19 ± 3.14 vs. 48.35 ± 4.38 min, P < 0.001), a higher overall good outcome "excellent + good" rate of screw placement (95.45% vs. 73.91%, P < 0.05), and a significantly higher Majeed Functional score better outcome of complex pelvic fracture treatment at 1 and 3 months postoperation (both P < 0.05). CONCLUSION: Our results demonstrated that O-arm navigation system is feasible and safe for the treatment of posterior pelvic ring injury and can effectively improve the accuracy and safety of sacroiliac screw placement, shorten the operation time, and help rapid postoperative functional recovery.
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Fracturas Óseas , Huesos Pélvicos , Cirugía Asistida por Computador , Adolescente , Adulto , Tornillos Óseos , Femenino , Fijación Interna de Fracturas , Fracturas Óseas/diagnóstico por imagen , Fracturas Óseas/cirugía , Humanos , Imagenología Tridimensional , Masculino , Persona de Mediana Edad , Huesos Pélvicos/diagnóstico por imagen , Huesos Pélvicos/cirugía , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Adulto JovenRESUMEN
Inorganic arsenic, an environmental contaminant, has adverse health outcomes. Our previous studies showed that arsenic causes abnormal cardiac development in zebrafish embryos by downregulating Dvr1/GDF1 expression and that folic acid protects against these effects. However, the mechanism by which arsenic represses Dvr1/GDF1 expression remains unknown. Herein, we demonstrate that specificity protein 1 (Sp1) acts as a transcriptional activator of GDF1. Arsenic treatment downregulated Sp1 at both the mRNA and protein level and its downstream targets GDF1 and SIRT1. Chromatin immunoprecipitation analysis showed that the occupancy of Sp1 on the GDF1 or SIRT1 promoter was significantly reduced in response to arsenite. Further investigation showed that Sp1 overexpression inhibited the arsenic-mediated decrease in GDF1 and SIRT1, while Sp1 knockdown had the opposite effect. We found that expression of the oxidative adaptor p66shc was inversely related to that of SIRT1 and that the binding of SIRT1 to the p66shc promoter was sharply attenuated by arsenite treatment. SIRT1 overexpression attenuated p66shc expression but enhanced GDF1 protein expression, while SIRT1 depletion exerted the opposite effect. Both the antioxidants N-acetylcysteine and folic acid reversed the arsenic-mediated repression of Sp1, GDF1 and SIRT1. Moreover, wild-type p66shc overexpression enhanced the arsenic-mediated repression of Sp1, GDF1 and SIRT1, which was accompanied by an increase in intracellular reactive oxygen species (ROS) levels, while both overexpression of a dominant negative p66shcSer36Ala mutant and deficiency in p66shc reversed these effects. Taken together, our results revealed that arsenic suppresses GDF1 expression via the ROS-dependent downregulation of the Sp1/SIRT1 axis, which forms a negative feedback loop with p66shc to regulate oxidative stress. Our findings reveal a novel molecular mechanism underlying arsenic toxicity and provide new insight into the protective effect of folic acid in arsenic-mediated toxicity.
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Arsénico , Factor 1 de Diferenciación de Crecimiento , Arsénico/toxicidad , Regulación hacia Abajo , Humanos , Estrés Oxidativo , Especies Reactivas de Oxígeno/metabolismo , Proteína Transformadora 1 que Contiene Dominios de Homología 2 de Src/genética , Proteína Transformadora 1 que Contiene Dominios de Homología 2 de Src/metabolismoRESUMEN
The eukaryotic cell cycle involves a highly orchestrated series of events in which the cellular genome is replicated during a synthesis (S) phase and each of the two resulting copies are segregated properly during mitosis (M). Host cell factor-1 (HCF-1) is a transcriptional co-regulator that is essential for and has been implicated in basic cellular processes, such as transcriptional regulation and cell cycle progression. Although a series of HCF-1 transcriptional targets have been identified, few functional clues have been provided, especially for chromosome segregation. Our results showed that HCF-1 activated CDC42 expression by binding to the -881 to -575 region upstream of the CDC42 transcription start site, and the regulation of CDC42 expression by HCF-1 was correlated with cell cycle progression. The overexpression of a spontaneously cycling and constitutively active CDC42 mutant (CDC42F28L) rescued G1 phase delay and multinucleate defects in mitosis upon the loss of HCF-1. Therefore, these results establish that HCF-1 ensures proper cell cycle progression by regulating the expression of CDC42, which indicates a possible mechanism of cell cycle coordination and the regulation mode of typical Rho GTPases.
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Factor C1 de la Célula Huésped/metabolismo , Proteína de Unión al GTP cdc42/metabolismo , Ciclo Celular/fisiología , Segregación Cromosómica , Ciclina A/biosíntesis , Ciclina A/genética , Progresión de la Enfermedad , Puntos de Control de la Fase G1 del Ciclo Celular , Técnicas de Silenciamiento del Gen , Células HEK293 , Células HeLa , Factor C1 de la Célula Huésped/genética , Humanos , Mitosis , Regiones Promotoras Genéticas , Proteína de Unión al GTP cdc42/biosíntesis , Proteína de Unión al GTP cdc42/genéticaRESUMEN
OBJECTIVE: Micro-nutrients are closely related to pulmonary tuberculosis (PTB). Most patients with PTB suffer from micro-nutrients deficiency. We aimed to evaluate the efficacy of micro-nutrients support on clinical therapy and chronic inflammation in patients with PTB. METHODS: We searched Pubmed, Springer link, Web of Science, Cochrane, Wan Fang and CNKI databases for randomised controlled trials (RCTs). The patients with anti-TB treatments were divided into two groups, the control group with nutritional advice or placebo, and the experimental group with micro-nutrients support for more than 2 weeks. Two reviewers conducted data extraction and quality assessment of the studies independently, and ReviewManager 5.2 software was used to input and analyse the data. The dichotomous variable was expressed in the risk ratios (RRS) and 95% CI, the continuous data were expressed in the mean difference (MD) and 95% CI, and the heterogeneity of subgroup was evaluated by I (Kerantzas and Jacobs, Jr., 2017) [2] test. RESULTS: A total of 13 trials (2847 participants) were included. First, micro-nutrients improved sputum smears or culture negative conversion rates (OR 0.16 0.03-0.77, 2.29; MD -2.36, -4.72~-0.01, z = 1.97). Meanwhile, micro-nutrients support increased lymphocytes and decreased leukocytes, neutrophils, CRP and ESR (MD 0.20, 0.06-0.35, z = 2.78; MD -0.42, -0.65~-0.18, z = 3.48; MD -0.66, -1.12~-0.20, z = 2.82). However it had not impact on body weight, MUAC, haemoglobin, albumin or monocytes (p > 0.05). CONCLUSION: Micro-nutrients support can reduce chronic inflammation and improve sputum smears or culture conversions to contribute to anti-TB treatment.
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Antituberculosos/uso terapéutico , Inmunidad Innata , Desnutrición/complicaciones , Mycobacterium tuberculosis/aislamiento & purificación , Nutrientes/farmacología , Ensayos Clínicos Controlados Aleatorios como Asunto , Tuberculosis Pulmonar/terapia , Humanos , Esputo/microbiología , Tuberculosis Pulmonar/etiología , Tuberculosis Pulmonar/microbiologíaRESUMEN
The molecular mechanism of Alzheimer-like cognitive impairment induced by manganese (Mn) exposure has not yet been fully clarified, and there are currently no effective interventions to treat neurodegenerative lesions related to manganism. Protein phosphatase 2 A (PP2A) is a major tau phosphatase and was recently identified as a potential therapeutic target molecule for neurodegenerative diseases; its activity is directed by the methylation status of the catalytic C subunit. Methionine is an essential amino acid, and its downstream metabolite S-adenosylmethionine (SAM) participates in transmethylation pathways as a methyl donor. In this study, the neurotoxic mechanism of Mn and the protective effect of methionine were evaluated in Mn-exposed cell and rat models. We show that Mn-induced neurotoxicity is characterized by PP2Ac demethylation accompanied by abnormally decreased LCMT-1 and increased PME-1, which are associated with tau hyperphosphorylation and spatial learning and memory deficits, and that the poor availability of SAM in the hippocampus is likely to determine the loss of PP2Ac methylation. Importantly, maintenance of local SAM levels through continuous supplementation with exogenous methionine, or through specific inhibition of PP2Ac demethylation by ABL127 administration in vitro, can effectively prevent tau hyperphosphorylation to reduce cellular oxidative stress, apoptosis, damage to cell viability, and rat memory deficits in cell or animal Mn exposure models. In conclusion, our data suggest that SAM and PP2Ac methylation may be novel targets for the treatment of Mn poisoning and neurotoxic mechanism-related tauopathies.
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Intoxicación por Manganeso/metabolismo , Manganeso/toxicidad , Metionina/metabolismo , Proteína Fosfatasa 2/metabolismo , Tauopatías/inducido químicamente , Tauopatías/metabolismo , Animales , Línea Celular Tumoral , Disfunción Cognitiva/inducido químicamente , Disfunción Cognitiva/metabolismo , Disfunción Cognitiva/patología , Hipocampo/efectos de los fármacos , Hipocampo/patología , Masculino , Intoxicación por Manganeso/patología , Metilación/efectos de los fármacos , Ratones , Ratas , Ratas Sprague-Dawley , Tauopatías/patologíaRESUMEN
OBJECTIVE: The obtain purified recombinant asprosin and test its functions. METHODS: The recombinant plasmid of pET-22b-asprosin was constructed and transformed into competent E.coli BL (DE3) strain. After IPTG-induced expression, asprosin inclusion body was renatured by gradient urea and purified by Ni-NTA affinity chromatography column followed by removal of endotoxin to obtain recombinant asprosin for use in cells and animals experiments. C57 mice were injected intraperitoneally with the recombinant asprosin and blood glucose was detected using a blood glucose meter. Alamar Blue assay was used to evaluate of the effect of the recombinant asprosin on the viability of MIHA cells, and cellular glycogen content was detected using the anthrone method. RESULTS: At the absorbance at 600 nm of 0.8, induction of the recombinant host bacteria with 1 mmol/L IPTG at 37 â for 4 h optimally induced the expression of asprosin inclusion body. After purification and endotoxin removal, the purity of the recombinant asprosin exceeded 95% with the content of endotoxin below 1 EU/mg. In C57 mice, intraperitoneal injection with recombinant asprosin significantly increased blood glucose level, which reached the peak level at 60 min following the injection (P=0.021) and recovered the normal level at 120 min (P=0.03). Treatment with the recombinant asprosin for 24 h did not cause obvious adverse effect on the viability of MIHA cells but significantly lowered glycogen content in the cells (P < 0.05). CONCLUSIONS: We successfully obtained recombinant asprosin using a prokaryotic expression system. The recombinant asprosin can decrease glycogen content in MIHA cells and increase blood glucose level in mice.
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Cuerpos de Inclusión , Proteínas de Microfilamentos/biosíntesis , Fragmentos de Péptidos/biosíntesis , Hormonas Peptídicas/biosíntesis , Animales , Glucemia/análisis , Línea Celular , Escherichia coli , Fibrilina-1 , Glucógeno/análisis , Humanos , Ratones , Ratones Endogámicos C57BL , Plásmidos , Proteínas Recombinantes/biosíntesisRESUMEN
Under strictly Framework Convention on Tobacco Control, novel tobacco products are going to be promising alterations to consumers and manufactures. Even though the novel tobacco products have been considered less harmful than traditional tobaccos, there is a few knowledges about the subsequent substances during consume and their impacts to the consumers due to short introduction into the market. Thus, the present study aims to investigate the adverse effects of novel tobacco products on Caenorhabditis elegans(C. elegans) and to provide relevant references for novel tobacco products toxicity research and assessment. C. elegans individuals at L4 stage were exposed to different kinds of novel tobacco products, including electronic cigarettes liquid (e-liquid), the extract of e-cig aerosol (e-aerosol), mint and black tea flavor snus. After specific exposure time, the multiple toxic endpoints of C. elegans were measured, including acute toxicity, locomotion behavior, body length, and life-span. The oxidative stress was tested too. According to acute toxicity assays, the half lethal dose of four novel tobacco products calculated from theoretical nicotine concentration, ranked as follows e-liquid (0.29â¯mg/ml)â¯>â¯the extract of e-cig aerosol (0.43â¯mg/ml)â¯>â¯mint flavor snus (1.20â¯mg/ml)â¯>â¯black tea flavor snus (1.50â¯mg/ml). The equivalent lethal rate 5%~20% of four novel tobacco products were applied to following experiments. These novel tobacco products damaged nematode's locomotion including head thrashing and body bending, the damage was most evident in two flavors of snus. The similar trends were found in reproductive performance investigation. At tested concentrations, the retardation development of C. elegans was found throughout all stages with peak blockage at adulthood. Life-span tests showed that novel tobacco products at 5% lethal rate seemed no significant effect on affected the life-span of nematodes, with snus shortened the lifespan of C. elegans at 20% lethal rate. Imaging stress response indicted four types of tobacco productions causing stress response in C. elegans. Exposed to either 5% or 20% lethal levels (5% and 20%), the percentages of worms with DAF-16 redistribution among all groups varied, with higher frequencies in both snus. Summary, novel tobacco products caused multiple adverse impacts to C. elegans, including acute toxicity, locomotion behavior disruption, brood size reduction, development retardation, and life-span reduction. The toxicity was associated with both the feature and concentration of tobacco products, and oxidative stress was the main mechanism.
Asunto(s)
Caenorhabditis elegans/efectos de los fármacos , Sistemas Electrónicos de Liberación de Nicotina , Productos de Tabaco/toxicidad , Animales , Animales Modificados Genéticamente , Caenorhabditis elegans/fisiología , Proteínas de Caenorhabditis elegans/genética , Factores de Transcripción Forkhead/genética , Locomoción/efectos de los fármacos , Longevidad/efectos de los fármacos , Reproducción/efectos de los fármacos , Pruebas de Toxicidad AgudaRESUMEN
Pentachloronitrobenzene (PCNB) is an organochlorine fungicide widely used for crop production and has become an environmental concern. Little is known about the effect of PCNB on ovarian steroidogenesis and follicular development. We found that PCNB stimulated Star expression and progesterone production in cultured rat granulosa cells in a dose-dependent manner. PCNB activated mitogen-activated protein kinase (MAPK3/1) extracellulat regulated kinase (ERK1/2), thus inhibition of either protein kinase A (PKA) or MAPK3/1 signaling pathway significantly attenuated progesterone biosynthesis caused by PCNB, suggesting that PCNB induced progesterone production by activating the cyclic adenosine monophosphate (cAMP/PKA) and MAPK3/1 signaling pathways. Further investigation demonstrated that PCNB induced Star expression and altered MAPK3/1 signaling in ovary tissues of immature SD rats treated with PCNB at the dose of 100, 200, or 300 mg/kg by daily gavage for 7 days, while serum progesterone level was dose-dependently decreased. We demonstrated that PCNB exposure accelerated the recruitment of primordial follicles into the growing follicle pool in ovary tissues, accompanied by increased levels of anti-Mullerian hormone (AMH) in both ovary tissues and serum. Taken together, our data demonstrate for the first time that PCNB stimulated Star expression, altered MAPK3/1 signaling and progesterone production in vivo and in vitro, and accelerated follicular development with a concomitant increase in AMH in ovary tissues and serum. Our findings provide novel insight into the toxicity of PCNB to animal ovary function.