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Sterol regulatory element-binding protein (SREBP)-1c is involved in cellular lipid homeostasis and cholesterol biosynthesis and is highly increased in nonalcoholic steatohepatitis (NASH). However, the molecular mechanism by which SREBP-1c regulates hepatic stellate cells (HSCs) activation in NASH animal models and patients have not been fully elucidated. In this study, we examined the role of SREBP-1c in NASH and the regulation of LCN2 gene expression. Wild-type and SREBP-1c knockout (1cKO) mice were fed a high-fat/high-sucrose diet, treated with carbon tetrachloride (CCl4), and subjected to lipocalin-2 (LCN2) overexpression. The role of LCN2 in NASH progression was assessed using mouse primary hepatocytes, Kupffer cells, and HSCs. LCN2 expression was examined in samples from normal patients and those with NASH. LCN2 gene expression and secretion increased in CCl4-induced liver fibrosis mice model, and SREBP-1c regulated LCN2 gene transcription. Moreover, treatment with holo-LCN2 stimulated intracellular iron accumulation and fibrosis-related gene expression in mouse primary HSCs, but these effects were not observed in 1cKO HSCs, indicating that SREBP-1c-induced LCN2 expression and secretion could stimulate HSCs activation through iron accumulation. Furthermore, LCN2 expression was strongly correlated with inflammation and fibrosis in patients with NASH. Our findings indicate that SREBP-1c regulates Lcn2 gene expression, contributing to diet-induced NASH. Reduced Lcn2 expression in 1cKO mice protects against NASH development. Therefore, the activation of Lcn2 by SREBP-1c establishes a new connection between iron and lipid metabolism, affecting inflammation and HSCs activation. These findings may lead to new therapeutic strategies for NASH.
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Hierro , Lipocalina 2 , Cirrosis Hepática , Ratones Noqueados , Enfermedad del Hígado Graso no Alcohólico , Proteína 1 de Unión a los Elementos Reguladores de Esteroles , Animales , Humanos , Masculino , Ratones , Tetracloruro de Carbono/farmacología , Modelos Animales de Enfermedad , Regulación de la Expresión Génica , Células Estrelladas Hepáticas/metabolismo , Células Estrelladas Hepáticas/patología , Hepatocitos/metabolismo , Hepatocitos/patología , Hierro/metabolismo , Lipocalina 2/metabolismo , Lipocalina 2/genética , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Cirrosis Hepática/etiología , Cirrosis Hepática/genética , Cirrosis Hepática/inducido químicamente , Ratones Endogámicos C57BL , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/etiología , Enfermedad del Hígado Graso no Alcohólico/patología , Enfermedad del Hígado Graso no Alcohólico/genética , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/metabolismo , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/genéticaRESUMEN
'Drug abuse' has been recognized as one of the most pressing epidemics in contemporary society. Traditional research has primarily focused on understanding how drugs induce neurotoxicity or degeneration within the central nervous system (CNS) and influence systems related to reward, motivation, and cravings. However, recent investigations have increasingly shifted their attention toward the detrimental consequences of drug abuse on the blood-brain barrier (BBB). The BBB is a structural component situated in brain vessels, responsible for separating brain tissue from external substances to maintain brain homeostasis. The BBB's function is governed by cellular interactions involving various elements of the 'neurovascular unit (NVU),' such as neurons, endothelial cells, astrocytes, pericytes, and microglia. Disruption of the NVU is closely linked to serious neurodegeneration. This review provides a comprehensive overview of the harmful effects of psychostimulant drugs on the BBB, highlighting the mechanisms through which drugs can damage the NVU. Additionally, the review proposes novel therapeutic targets aimed at protecting the BBB. By understanding the intricate relationships between drug abuse, BBB integrity, and NVU function, researchers and clinicians may uncover new strategies to mitigate the damaging impact of drug abuse on brain health.
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Células Endoteliales , Trastornos Relacionados con Sustancias , Humanos , Encéfalo , Barrera Hematoencefálica , Sistema Nervioso Central , Trastornos Relacionados con Sustancias/etiologíaRESUMEN
Human sterile α motif and HD domain-containing protein 1 (SAMHD1) has deoxyribonucleoside triphosphohydrolase (dNTPase) activity that allows it to defend against human immunodeficiency virus type I (HIV-1) infections and regulate the cell cycle. Although SAMHD1 mutations have been identified in various cancer types, their role in cancer is unclear. Here, we aimed to investigate the oncogenic role of SAMHD1 in human clear cell renal cell carcinoma (ccRCC), particularly as a core molecule promoting cancer cell migration. We found that SAMHD1 participated in endocytosis and lamellipodia formation. Mechanistically, SAMHD1 contributed to the formation of the endosomal complex by binding to cortactin. Thereafter, SAMHD1-stimulated endosomal focal adhesion kinase (FAK) signaling activated Rac1, which promoted lamellipodia formation on the plasma membrane and enhanced the motility of ccRCC cells. Finally, we observed a strong correlation between SAMHD1 expression and the activation of FAK and cortactin in tumor tissues obtained from patients with ccRCC. In brief, these findings reveal that SAMHD1 is an oncogene that plays a pivotal role in ccRCC cell migration through the endosomal FAK-Rac1 signaling pathway.
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Carcinoma de Células Renales , Neoplasias Renales , Humanos , Carcinoma de Células Renales/genética , Cortactina , Proteína-Tirosina Quinasas de Adhesión Focal , Proteína 1 que Contiene Dominios SAM y HD , Seudópodos , Transducción de Señal , Neoplasias Renales/genética , Proteína de Unión al GTP rac1/genéticaRESUMEN
Methamphetamine (MA) is a extremely addictive psychostimulant drug with a significant abuse potential. Long-term MA exposure can induce neurotoxic effects through oxidative stress, mitochondrial functional impairment, endoplasmic reticulum stress, the activation of astrocytes and microglial cells, axonal transport barriers, autophagy, and apoptosis. However, the molecular and cellular mechanisms underlying MA-induced neurotoxicity remain unclear. MA abuse increases the chances of developing neurotoxic conditions such as Parkinson's disease (PD), Alzheimer's disease (AD) and other neurotoxic diseases. MA increases the risk of PD by increasing the expression of alpha-synuclein (ASYN). Furthermore, MA abuse is linked to high chances of developing AD and subsequent neurodegeneration due to biological variations in the brain region or genetic and epigenetic variations. To date, there is no Food and Drug Administration (FDA)-approved therapy for MA-induced neurotoxicity, although many studies are being conducted to develop effective therapeutic strategies. Most current studies are now focused on developing therapies to diminish the neurotoxic effects of MA, based on the underlying mechanism of neurotoxicity. This review article highlights current research on several therapeutic techniques targeting multiple pathways to reduce the neurotoxic effects of MA in the brain, as well as the putative mechanism of MA-induced neurotoxicity.
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Trastornos Relacionados con Anfetaminas , Estimulantes del Sistema Nervioso Central , Metanfetamina , Síndromes de Neurotoxicidad , Enfermedad de Parkinson , Trastornos Relacionados con Anfetaminas/complicaciones , Trastornos Relacionados con Anfetaminas/terapia , Astrocitos , Estimulantes del Sistema Nervioso Central/toxicidad , Humanos , Metanfetamina/toxicidad , Síndromes de Neurotoxicidad/etiología , Síndromes de Neurotoxicidad/terapiaRESUMEN
Cancer stem cells (CSCs) are the subpopulation of cells present within a tumor with the properties of self-renewing, differentiating, and proliferating. Owing to the presence of ATP-binding cassette drug pumps and increased expression of anti-apoptotic proteins, the conventional chemotherapeutic agents have failed to eliminate CSCs resulting in relapse and resistance of cancer. Therefore, to obtain long-lasting clinical responses and avoid the recurrence of cancer, it is crucial to develop an efficient strategy targeting CSCs by either employing a differentiation therapy or specifically delivering drugs to CSCs. Several intracellular and extracellular cancer specific biomarkers are overexpressed by CSCs and are utilized as targets for the development of new approaches in the diagnosis and treatment of CSCs. Moreover, several nanostructured particles, alone or in combination with current treatment approaches, have been used to improve the detection, imaging, and targeting of CSCs, thus addressing the limitations of cancer therapies. Targeting CSC surface markers, stemness-related signaling pathways, and tumor microenvironmental signals has improved the detection and eradication of CSCs and, therefore, tumor diagnosis and treatment. This review summarizes a variety of promising nanoparticles targeting the surface biomarkers of CSCs for the detection and eradication of tumor-initiating stem cells, used in combination with other treatment regimens.
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Nanopartículas , Neoplasias , Biomarcadores de Tumor/metabolismo , Humanos , Nanopartículas/uso terapéutico , Neoplasias/diagnóstico , Neoplasias/tratamiento farmacológico , Células Madre Neoplásicas/metabolismo , VirtudesRESUMEN
Aims: Ribosomal protein L17 (RPL17), a 60S subunit component, is up-regulated in colorectal cancer (CRC). However, its oncogenic role in CRC progression remains unexplored. Thus, we aimed to investigate the effect of RPL17 targeting on CRC in vitro and in vivo and whether RPL17 gained an extra-ribosomal function during CRC development. Methods: RPL17-specific siRNAs complexed with cationic lipids were transfected to CRC cells to silence target gene expression and then real-time RT-PCR and western blotting were applied to observe the change of expression or activity of genes or proteins of interest. Cell proliferation assay, clonogenic assay and cell cycle analysis were used to determine the in vitro effects of RPL17siRNAs on CRC cell growth, and a subcutaneous xenograft assay was applied to test the effect of RPL17siRNAs on in vivo tumor growth. RNA sequencing and western blotting were used to investigate the underlying mechanisms. Sphere-forming assay, invasion assay and migration assay were used to evaluate the effects of RPL17siRNAs on CRC stemness. Results: siRNA-mediated inhibition of RPL17 expression suppressed CRC cell growth and long-term colony formation by inducing apoptotic cell death. Similarly, targeting RPL17 effectively suppressed tumor formation in a mouse xenograft model. RNA sequencing of RPL17-silenced CRC cells revealed the same directional regulation of 159 (93 down- and 66 up-regulated) genes. Notably, NIMA-related kinase 2 (NEK2), which functionally cooperates with extracellular-regulated protein kinase (ERK) and plays a pivotal role in mitotic progression and stemness maintenance, was down-regulated. RPL17 silencing reduced NEK2, ß-catenin, and p-ERK protein levels. These molecular alterations reflected the reduction in sphere-forming capacity, expression of stem cell marker genes, migration, and invasion. Reversely, RPL17 overexpression increased the ability of long-term colony formation, migration, and invasion. Conclusion: Our findings indicate that RPL17 promotes CRC proliferation and stemness via the ERK and NEK2/ß-catenin signaling axis, and targeting RPL17 could be the next molecular strategy for both primary CRC treatment and prevention of secondary tumor formation.
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Studies report beneficial effects of 3-hydroxybutyrate (3-OHB) on the treatment of type 2 diabetes and obesity, but the effects of 3-OHB on diabetic nephropathy have not been elucidated. This study was designed to investigate the efficacy and mechanism of 3-OHB against progression of diabetic nephropathy (DN). Mice (db/db) were fed normal chow, high-fat, or ketogenic diets (KD) containing precursors of 3-OHB. Hyperglycemia was determined based on random glucose level (≥250 mg/dL). Fasting blood glucose and body weights were measured once a week. Twenty four-hour urine albumin to creatinine ratio was determined 5 weeks after the differential diet. Energy expenditure was measured 9 weeks after the differential diet. Body weights were significantly lower in the KD group than those in other groups, but no significant differences in fasting blood glucose levels among three groups were observed. Urine albumin to creatinine ratio and serum blood urea nitrogen (BUN) to creatinine ratio in the KD group were significantly lower than in other groups. Histologic and quantitative analysis of mesangial area suggested that KD delayed the progression of DN phenotype in db/db mice. Metabolic cage analysis also revealed that KD increased energy expenditure in db/db mice. In vitro studies with proximal tubular cells revealed that 3-OHB stimulated autophagic flux. 3-OHB increased LC3 I to LC3 II ratio, phosphorylation of AMPK, beclin, p62 degradation, and NRF2 expression. Moreover, we found that 3-OHB attenuated high glucose-induced reactive oxygen species (ROS) levels in proximal tubular cells. In vivo study also confirmed increased LC3 and decreased ROS levels in the kidney of KD mice. In summary, this study shows in both in vivo and in vitro models that 3-OHB delays the progression of DN by augmenting autophagy and inhibiting oxidative stress.
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The pandemic outbreak of COVID-19 in the year of 2020 that drastically changed everyone's life has raised the urgent and intense need for the development of more efficacious antiviral material. This study was designed to develop copper nanoparticles (Cu NPs) as an antiviral agent and to validate the antiviral activities of developed copper NP. The Cu NPs were synthesized using a high energy electron beam, and the characteristic morphologies and antiviral activities of Cu NPs were evaluated. We found that Cu NPs are of spherical shape and uniformly distributed, with a diameter of around 100 nm, as opposed to the irregular shape of commercially available copper microparticles (Cu MPs). An X-ray diffraction analysis showed the presence of Cu and no copper oxide II and I in the Cu NPs. A virus inactivation assay revealed no visible viral DNA after 10- and 30-min treatment of H1N1 virus with the Cu NPs. The infectivity of the Cu NPs-treated H1N1 virus significantly decreased compared with that of the Cu MPs-treated H1N1 virus. The viability of A549 bronchial and Madin-Darby Canine Kidney (MDCK) cells infected with Cu NPs-treated H1N1 was significantly higher than those infected with Cu MPs-treated H1N1 virus. We also found cells infected with Cu NPs-treated H1N1 virus exhibited a markedly decreased presence of virus nucleoprotein (NuP), an influenza virus-specific structural protein, compared with cells infected with Cu MPs-treated H1N1 virus. Taken together, our study shows that Cu NPs are a more effective and efficacious antiviral agent compared with Cu MPs and offer promising opportunities for the prevention of devastatingly infectious diseases.
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Cathepsin K is highly expressed in various types of cancers. However, the effect of cathepsin K inhibition in cancer cells is not well characterized. Here, cathepsin K inhibitor (odanacatib; ODN) and knockdown of cathepsin K (siRNA) enhanced oxaliplatin-induced apoptosis in multiple cancer cells through Bax upregulation. Bax knockdown significantly inhibited the combined ODN and oxaliplatin treatment-induced apoptotic cell death. Stabilization of p53 by ODN played a critical role in upregulating Bax expression at the transcriptional level. Casein kinase 2 (CK2)-dependent phosphorylation of OTUB1 at Ser16 played a critical role in ODN- and cathepsin K siRNA-mediated p53 stabilization. Interestingly, ODN-induced p53 and Bax upregulation were modulated by the production of mitochondrial reactive oxygen species (ROS). Mitochondrial ROS scavengers prevented OTUB1-mediated p53 stabilization and Bax upregulation by ODN. These in vitro results were confirmed by in mouse xenograft model, combined treatment with ODN and oxaliplatin significantly reduced tumor size and induced Bax upregulation. Furthermore, human renal clear carcinoma (RCC) tissues revealed a strong correlation between phosphorylation of OTUB1(Ser16) and p53/Bax expression. Our results demonstrate that cathepsin K inhibition enhances oxaliplatin-induced apoptosis by increasing OTUB1 phosphorylation via CK2 activation, thereby promoting p53 stabilization, and hence upregulating Bax.
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Antineoplásicos/uso terapéutico , Catepsina K/metabolismo , Oxaliplatino/uso terapéutico , Proteína p53 Supresora de Tumor/genética , Proteína X Asociada a bcl-2/genética , Animales , Antineoplásicos/farmacología , Apoptosis , Muerte Celular , Línea Celular Tumoral , Humanos , Ratones , Oxaliplatino/farmacología , Regulación hacia ArribaRESUMEN
Histone deacetylase 6 (HDAC6) is a promising target for cancer treatment because it regulates cell mobility, protein trafficking, cell growth, apoptosis, and metastasis. However, the mechanism of HDAC6-induced anticancer drug resistance is unclear. In this study, we evaluated the anticancer effect of ACY-241, an HDAC6-selective inhibitor, on erlotinib-resistant pancreatic cancer cells that overexpress HDAC6. Our data revealed that ACY-241 hyperacetylated the HDAC6 substrate, α-tubulin, leading to a significant reduction in cell viability of erlotinib-resistant pancreatic cells, BxPC3-ER and HPAC-ER. Notably, a synergistic anticancer effect was observed in cells that received combined treatment with ACY-241 and erlotinib. Combined treatment effectively induced autophagy and inhibited autophagy through siLC3B, and siATG5 alleviated ACY-241-mediated cell death, as reflected by the recovery of PARP cleavage and apoptosis rates. In addition, combined ACY-241 and erlotinib treatment induced autophagy and subsequently, cell death by reducing AKT-mTOR activity and increasing phospho-AMPK signaling. Therefore, HDAC6 may be involved in the suppression of autophagy and acquisition of resistance to erlotinib in ER pancreatic cancer cells. ACY-241 to overcome erlotinib resistance could be an effective therapeutic strategy against pancreatic cancer.
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Clorhidrato de Erlotinib , Inhibidores de Histona Desacetilasas , Neoplasias Pancreáticas , Pirimidinas , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Sinergismo Farmacológico , Clorhidrato de Erlotinib/farmacología , Histona Desacetilasa 6/antagonistas & inhibidores , Inhibidores de Histona Desacetilasas/farmacología , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/patología , Pirimidinas/farmacología , Transducción de Señal/efectos de los fármacosRESUMEN
The dysregulation of fibroblast growth factor (FGF) signaling has been implicated in tumorigenesis, tumor progression, angiogenesis, and chemoresistance. The small-molecule AZD4547 is a potent inhibitor of FGF receptors. This study was performed to investigate the antitumor effects and determine the mechanistic details of AZD4547 in ovarian cancer cells. AZD4547 markedly inhibited the proliferation and increased the apoptosis of ovarian cancer cells. AZD4547 also suppressed the migration and invasion of ovarian cancer cells under nontoxic conditions. Furthermore, it attenuated the formation of spheroids and the self-renewal capacities of ovarian cancer stem cells and exerted an antiangiogenic effect. It also suppressed in vivo tumor growth in mice. Collectively, this study demonstrated the antitumor effect of AZD4547 in ovarian cancer cells and suggests that it is a promising agent for ovarian cancer therapy.
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Benzamidas/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Neoplasias Ováricas/tratamiento farmacológico , Piperazinas/farmacología , Pirazoles/farmacología , Receptores de Factores de Crecimiento de Fibroblastos/antagonistas & inhibidores , Animales , Apoptosis , Movimiento Celular , Proliferación Celular , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/patología , Pronóstico , Tasa de Supervivencia , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Big data analysis has revealed the upregulation of cell division cycle associated 8 (CDCA8) in human hepatocellular carcinoma (HCC) and its poorer survival outcome. However, the functions of CDCA8 during HCC development remain unknown. Here, we demonstrate in vitro that CDCA8 silencing inhibits HCC cell growth and long-term colony formation and migration through the accumulation of the G2/M phase cell population. Conversely, CDCA8 overexpression increases the ability to undergo long-term colony formation and migration. RNA sequencing and bioinformatic analysis revealed that CDCA8 knockdown led to the same directional regulation in 50 genes (25 down- and 25 upregulated). It was affirmed based on protein levels that CDCA8 silencing downregulates the levels of cyclin B1 and p-cdc2 and explains how it could induce G2/M arrest. The same condition increased the protein levels of tumor-suppressive ATF3 and GADD34 and inactivated AKT/ß-catenin signaling, which plays an important role in cell growth and stemness, reflecting a reduction in sphere-forming capacity. Importantly, it was demonstrated that the extent of CDCA8 expression is much greater in CD133+ cancer stem cells than in CD133- cancer cells, and that CDCA8 knockdown decreases levels of CD133, p-Akt and ß-catenin and increases levels of ATF3 and GADD34 in the CD133+ cancer stem cell (CSC) population. These molecular changes led to the inhibition of cell growth and sphere formation in the CD133+ cell population. Targeting CDCA8 also effectively suppressed tumor growth in a murine xenograft model, showing consistent molecular alterations in tumors injected with CDCA8siRNA. Taken together, these findings indicate that silencing CDCA8 suppresses HCC growth and stemness via restoring the ATF3 tumor suppressor and inactivating oncogenic AKT/ß-catenin signaling, and that targeting CDCA8 may be the next molecular strategy for both primary HCC treatment and the prevention of metastasis or recurrence.
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We previously reported that the duodenal-jejunal bypass (DJB) surgery altered transsulfuration and purine metabolism via flux changes in 1-carbon metabolism in the liver. In this study, we extended our study to gain further insight into mechanistic details of how the DJB-induced flux changes in 1-carbon metabolism contributes to the improvement of diet-induced nonalcoholic fatty liver disease. Rodents were subjected to surgical (sham operation and DJB) or dietary (reduced food supply to follow the weight changes in the DJB group) interventions. The microscopic features of the liver were examined by immunohistochemistry. The expressions of genes in lipid synthesis and in 1-carbon cycle in the liver were analyzed by real-time polymerase chain reaction and western blotting. Metabolic changes in the liver were determined. We observed that DJB reduces hepatic steatosis and improves insulin sensitivity in both high-fat diet-fed rats and mice. Metabolic analyses revealed that the possible underlying mechanism may involve decreased S-adenosylmethionine (SAM)-to-S-adenosylhomocysteine ratio via downregulation of SAM synthesizing enzyme and upregulation of SAM catabolizing enzyme. We also found in mice that DJB-mediated attenuation of hepatic steatosis is independent of weight loss. DJB also increased hepatic expression levels of GNMT while decreasing those of PEMT and BHMT, a change in 1-carbon metabolism that may decrease the ratio of SAM to S-adenosylhomocysteine, thereby resulting in the prevention of fat accumulation in the liver. Thus, we suggest that the change in 1-carbon metabolism, especially the SAM metabolism, may contribute to the improvement of diet-induced fatty liver disease after DJB surgery.
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Homocisteína , S-Adenosilmetionina , Animales , Dieta Alta en Grasa , Duodeno , Yeyuno , Hígado , Ratones , Obesidad/etiología , Obesidad/cirugía , Fosfatidiletanolamina N-Metiltransferasa , RatasRESUMEN
Protein kinase C-δ (PKCδ) is a diacylglycerol-dependent, calcium-independent novel PKC isoform that is engaged in various cell signaling pathways, such as cell proliferation, apoptosis, inflammation, and oxidative stress. In this study, we searched for proteins that bind PKCδ using a yeast two-hybrid assay and identified murine arrest-defective 1 (mARD1) as a binding partner. The interaction between PKCδ and mARD1 was confirmed by glutathione S-transferase pull-down and co-immunoprecipitation assays. Furthermore, recombinant PKCδ phosphorylated full-length mARD1 protein. The NetPhos online prediction tool suggested PKCδ phosphorylates Ser80 , Ser108 , and Ser114 residues of mARD1 with the highest probability. Based on these results, we synthesized peptides containing these sites and examined their phosphorylations using recombinant PKCδ. Autoradiography confirmed these sites were efficiently phosphorylated. Consequent mass spectrometry and peptide sequencing in combination with MALDI-TOF MS/MS confirmed that Ser80 and Ser108 were major phosphorylation sites. The alanine mutations of Ser80 and Ser108 abolished the phosphorylation of mARD1 by PKCδ in 293T cells supporting these observations. In addition, kinase assays using various PKC isotypes showed that Ser80 of ARD1 was phosphorylated by PKCßI and PKCζ isotypes with the highest selectivity, while Ser108 and/or Ser114 were phosphorylated by PKCγ with activities comparable to that of the PKCδ isoform. Overall, these results suggest the possibility that PKCδ transduces signals by regulating phosphorylation of ARD1.
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Acetiltransferasa A N-Terminal/metabolismo , Acetiltransferasa E N-Terminal/metabolismo , Fosforilación/fisiología , Proteína Quinasa C-delta/metabolismo , Secuencia de Aminoácidos , Animales , Línea Celular , Línea Celular Tumoral , Células HEK293 , Células HeLa , Humanos , Ratones , Estrés Oxidativo/fisiología , Péptidos/metabolismo , Isoformas de Proteínas/metabolismo , Serina/metabolismo , Transducción de Señal/fisiologíaRESUMEN
A-kinase anchor protein 12 (AKAP12) is a scaffolding protein that associates with intracellular molecules to regulate multiple signal transductions. Although the roles of AKAP12 in the central nervous system are still relatively understudied, it was previously shown that AKAP12 regulates blood-retinal barrier formation. In this study, we asked whether AKAP12 also supports the function and integrity of the blood-brain barrier (BBB). In a mouse model of focal ischemia, the expression level of AKAP12 in cerebral endothelial cells was upregulated during the acute phase of stroke. Also, in cultured cerebral endothelial cells, oxygen-glucose deprivation induced the upregulation of AKAP12. When AKAP12 expression was suppressed by an siRNA approach in cultured endothelial cells, endothelial permeability was increased along with the dysregulation of ZO-1/Claudin 5 expression. In addition, the loss of AKAP12 expression caused an upregulation/activation of the Rho kinase pathway, and treatment of Rho kinase inhibitor Y-27632 mitigated the increase of endothelial permeability in AKAP12-deficient endothelial cell cultures. These in vitro findings were confirmed by our in vivo experiments using Akap12 knockout mice. Compared to wild-type mice, Akap12 knockout mice showed a larger extent of BBB damage after stroke. However, the inhibition of rho kinase by Y-27632 tightened the BBB in Akap12 knockout mice. These data may suggest that endogenous AKAP12 works to alleviate the damage and dysfunction of the BBB caused by ischemic stress. Therefore, the AKAP12-rho-kinase signaling pathway represents a novel therapeutic target for stroke.
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Proteínas de Anclaje a la Quinasa A/metabolismo , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/patología , Proteínas de Ciclo Celular/metabolismo , Accidente Cerebrovascular Isquémico/metabolismo , Accidente Cerebrovascular Isquémico/patología , Animales , Permeabilidad de la Membrana Celular , Endotelio Vascular/patología , Ratones Endogámicos C57BL , Ratones Noqueados , Quinasas Asociadas a rho/metabolismoRESUMEN
Methamphetamine (METH) is a powerful psychostimulant that is causing serious health problems worldwide owing to imprudent abuses. Recent studies have suggested that METH has deleterious effects on the blood-brain barrier (BBB). A few studies have also been conducted on the mechanisms whereby METH-induced oxidative stress causes BBB dysfunction. We investigated whether N-tert-butyl-α-phenylnitrone (PBN) has protective effects on BBB function against METH exposure in primary human brain microvascular endothelial cells (HBMECs). We found that METH significantly increased reactive oxygen species (ROS) generation in HBMECs. Pretreatment with PBN decreased METH-induced ROS production. With regard to BBB functional integrity, METH exposure elevated the paracellular permeability and reduced the monolayer integrity; PBN treatment reversed these effects. An analysis of the BBB structural properties, by immunostaining junction proteins and cytoskeleton in HBMECs, indicated that METH treatment changed the cellular localization of the tight (ZO-1) and adherens junctions (VE-cadherin) from the membrane to cytoplasm. Furthermore, METH induced cytoskeletal reorganization via the formation of robust stress fibers. METH-induced junctional protein redistribution and cytoskeletal reorganization were attenuated by PBN treatment. Our results suggest that PBN can act as a therapeutic reagent for METH-induced BBB dysfunction by inhibiting excess ROS generation.
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Antioxidantes/farmacología , Barrera Hematoencefálica/efectos de los fármacos , Permeabilidad Capilar/efectos de los fármacos , Estimulantes del Sistema Nervioso Central/toxicidad , Óxidos N-Cíclicos/farmacología , Células Endoteliales/efectos de los fármacos , Metanfetamina/toxicidad , Estrés Oxidativo/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Antígenos CD/metabolismo , Barrera Hematoencefálica/metabolismo , Cadherinas/metabolismo , Células Cultivadas , Citoesqueleto/efectos de los fármacos , Citoesqueleto/metabolismo , Impedancia Eléctrica , Células Endoteliales/metabolismo , Humanos , Uniones Estrechas/efectos de los fármacos , Uniones Estrechas/metabolismo , Proteína de la Zonula Occludens-1/metabolismoRESUMEN
N-α-acetyltransferase 10 (NAA10) is an acetyltransferase that acetylates both N-terminal amino acid and internal lysine residues of proteins. NAA10 is a crucial player to regulate cell proliferation, migration, differentiation, apoptosis, and autophagy. Recently, mounting evidence presented the overexpression of NAA10 in various types of cancer, including liver, bone, lung, breast, colon, and prostate cancers, and demonstrated a correlation of overexpressed NAA10 with vascular invasion and metastasis, thereby affecting overall survival rates of cancer patients and recurrence of diseases. This evidence all points NAA10 toward a promising biomarker for cancer prognosis. Here we summarize the current knowledge regarding the biological functions of NAA10 in cancer progression and provide the potential usage of NAA10 as a prognostic marker for cancer progression.
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Biomarcadores de Tumor/metabolismo , Acetiltransferasa A N-Terminal/metabolismo , Acetiltransferasa E N-Terminal/metabolismo , Neoplasias/patología , Progresión de la Enfermedad , Humanos , Neoplasias/metabolismoRESUMEN
The present study was designed to determine the effects of pineal glandderived melatonin on obesity by employing a rat pinealectomy (Pnx) model. After 10 weeks of a highfat diet, rats received sham or Pnx surgery followed by a normal chow diet for 10 weeks. Reverse transcriptionquantitative PCR, western blotting analysis, immunohistochemistry and ELISA were used to determine the effects of Pnx. Pnx decreased the expression of melatonin receptor (MTNR)1A and MTNR1B, in brown adipose tissues (BAT) and white adipose tissues (WAT). Pnx rats showed increased insulin sensitivity compared with those that received sham surgery. Leptin levels were significantly decreased in the serum of the Pnx group. In addition, Pnx stimulated thermogenic genes in BAT and attenuated lipogenic genes in both WAT and the liver. Histological analyses revealed a marked decrease in the size of lipid droplets and increased expression of uncoupling protein 1 in BAT. In the liver of the Pnx group, the size and number of lipid droplets had also decreased. In conclusion, the results presented in the current study suggested that Pnx increases thermogenesis in BAT and decreases lipogenesis in WAT and the liver.
Asunto(s)
Lipogénesis , Obesidad/metabolismo , Pinealectomía/métodos , Termogénesis , Tejido Adiposo Pardo/metabolismo , Tejido Adiposo Blanco/metabolismo , Animales , Modelos Animales de Enfermedad , Regulación hacia Abajo , Regulación de la Expresión Génica , Resistencia a la Insulina , Leptina/sangre , Hígado/metabolismo , Masculino , Obesidad/etiología , Obesidad/genética , Ratas , Receptor de Melatonina MT1/genética , Receptor de Melatonina MT1/metabolismoRESUMEN
In this study, a new recirculation column reactor system for arsenate removal using a polyethylenimine coated bacterial biosorbent was developed. Solution pH was the most important factor in process design and operation. In order to control and optimize solution pH favorable for arsenate removal, a pH control and recirculation system was added to a column reactor. The effects of recycle ratio, initial arsenate concentration, and flow rate on the arsenate removal performance of the developed process were examined. Thomas and Yoon-Nelson models were used to interpret the breakthrough curve of arsenate removal. The maximum arsenate adsorption amount of the new reactor was determined to be 50.86 mg/g by the Thomas model. Importantly, the new reactor showed unimpeded adsorption performance compared with that in the batch experiments. The desorption study also showed excellent reusability. The results indicated that the newly developed process could be a promising application prospect for removing arsenate.
Asunto(s)
Contaminantes Químicos del Agua/análisis , Purificación del Agua , Adsorción , Arseniatos , Concentración de Iones de Hidrógeno , Cinética , Estudios LongitudinalesRESUMEN
AIMS: Methamphetamine (METH) is an abused psychostimulant causing public health concern worldwide. While most studies have focused on the neurotoxic effects of METH, METH-induced cerebrovascular dysfunction has recently drawn attention as an important facet of METH-related pathophysiology. In this study, we investigated the protective role of GKT136901, a NOX1/4 inhibitor, against METH-induced blood-brain barrier (BBB) dysfunction. MAIN METHODS: Primary human brain microvascular endothelial cells (HBMECs) were used as an in vitro BBB model. HBMECs were treated with GKT136901, followed by METH exposure for 24 h. The generation of reactive oxidative species (ROS) was measured using 2',7'-dichlorofluorescin diacetate (DCF-DA) staining. To examine the BBB function, paracellular permeability of HBMEC monolayer was measured using FITC-labeled dextran. To evaluate structural properties of BBB in HBMECs, tight junction (TJ), adherent junction (AJ), and cytoskeletal proteins were stained and analyzed by confocal microscopy. KEY FINDINGS: METH treatment rapidly increased ROS generation in HBMECs but GKT136901 treatment inhibited METH-induced ROS generation. Although METH increased the permeability of HBMEC monolayer, this effect was abolished upon GKT136901 treatment. Following METH exposure, the proteins Zonula occludens-1 (ZO-1) and vascular endothelial cadherin (VE-cadherin) were translocalized from the cell membrane to the cytoplasm, thereby destroying intercellular tight junction (TJ) and adherent junction (AJ) structures, which were ameliorated upon GKT136901 treatment. METH exposure altered the cellular morphology of HBMECs and induced stress fiber formation. However, GKT136901 prevented METH-induced morphological and cytoskeletal changes in HBMECs. SIGNIFICANCE: These results suggest that GKT136901 prevents METH-induced BBB dysfunction in HBMECs through the inhibition of ROS generation.