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Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a 'highly transmissible respiratory pathogen, leading to severe multi-organ damage. However, knowledge regarding SARS-CoV-2-induced cellular alterations is limited. In this study, we report that SARS-CoV-2 aberrantly elevates mitochondrial bioenergetics and activates the EGFR-mediated cell survival signal cascade during the early stage of viral infection. SARS-CoV-2 causes an increase in mitochondrial transmembrane potential via the SARS-CoV-2 RNA-nucleocapsid cluster, thereby abnormally promoting mitochondrial elongation and the OXPHOS process, followed by enhancing ATP production. Furthermore, SARS-CoV-2 activates the EGFR signal cascade and subsequently induces mitochondrial EGFR trafficking, contributing to abnormal OXPHOS process and viral propagation. Approved EGFR inhibitors remarkably reduce SARS-CoV-2 propagation, among which vandetanib exhibits the highest antiviral efficacy. Treatment of SARS-CoV-2-infected cells with vandetanib decreases SARS-CoV-2-induced EGFR trafficking to the mitochondria and restores SARS-CoV-2-induced aberrant elevation in OXPHOS process and ATP generation, thereby resulting in the reduction of SARS-CoV-2 propagation. Furthermore, oral administration of vandetanib to SARS-CoV-2-infected hACE2 transgenic mice reduces SARS-CoV-2 propagation in lung tissue and mitigates SARS-CoV-2-induced lung inflammation. Vandetanib also exhibits potent antiviral activity against various SARS-CoV-2 variants of concern, including alpha, beta, delta and omicron, in in vitro cell culture experiments. Taken together, our findings provide novel insight into SARS-CoV-2-induced alterations in mitochondrial dynamics and EGFR trafficking during the early stage of viral infection and their roles in robust SARS-CoV-2 propagation, suggesting that EGFR is an attractive host target for combating COVID-19.
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COVID-19 , Receptores ErbB , Mitocondrias , SARS-CoV-2 , Replicación Viral , SARS-CoV-2/efectos de los fármacos , Mitocondrias/metabolismo , Mitocondrias/genética , Mitocondrias/efectos de los fármacos , Humanos , Animales , Ratones , COVID-19/virología , COVID-19/metabolismo , COVID-19/genética , Receptores ErbB/metabolismo , Receptores ErbB/genética , Replicación Viral/efectos de los fármacos , Metabolismo Energético/efectos de los fármacos , Metabolismo Energético/genética , Células Vero , Chlorocebus aethiops , Antivirales/farmacología , Tratamiento Farmacológico de COVID-19 , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Fosforilación Oxidativa/efectos de los fármacos , Transducción de Señal/efectos de los fármacosRESUMEN
The liver-specific microRNA, miR-122, plays an essential role in the propagation of hepatitis C virus (HCV) by binding directly to the 5'-end of its genomic RNA. Despite its significance for HCV proliferation, the host factors responsible for regulating miR-122 remain largely unknown. In this study, we identified the cellular RNA-binding protein, ELAVL1/HuR (embryonic lethal-abnormal vision-like 1/human antigen R), as critically contributing to miR-122 biogenesis by strong binding to the 3'-end of miR-122. The availability of ELAVL1/HuR was highly correlated with HCV proliferation in replicon, infectious, and chronically infected patient conditions. Furthermore, by screening a kinase inhibitor library, we identified rigosertib, an anticancer agent under clinical trials, as having both miR-122-modulating and anti-HCV activities that were mediated by its ability to target polo-like kinase 1 (PLK1) and subsequently modulate ELAVL1/HuR-miR-122 signaling. The expression of PLK1 was also highly correlated with HCV proliferation and the HCV positivity of HCC patients. ELAVL1/HuR-miR-122 signaling and its mediation of PLK1-dependent HCV proliferation were demonstrated by performing various rescue experiments and utilizing an HCV mutant with low dependency on miR-122. In addition, the HCV-inhibitory effectiveness of rigosertib was validated in various HCV-relevant conditions, including replicons, infected cells, and replicon-harboring mice. Rigosertib was highly effective in inhibiting the proliferation of not only wild-type HCVs, but also sofosbuvir resistance-associated substitution-bearing HCVs. Our study identifies PLK1-ELAVL1/HuR-miR-122 signaling as a regulatory axis that is critical for HCV proliferation, and suggests that a therapeutic approach targeting this host cell signaling pathway could be useful for treating HCV and HCV-associated diseases.
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Carcinoma Hepatocelular , Hepatitis C , Neoplasias Hepáticas , MicroARNs , Animales , Humanos , Ratones , Carcinoma Hepatocelular/genética , Proliferación Celular , Proteína 1 Similar a ELAV/genética , Proteína 1 Similar a ELAV/metabolismo , Hepacivirus/fisiología , Hepatitis C/genética , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/genética , MicroARNs/genética , MicroARNs/metabolismo , Transducción de Señal , Quinasa Tipo Polo 1RESUMEN
In South Korea, the suicide rate is more than double the OECD average, and precise identification of the cause is required for suicide prevention. Psychological autopsy is used to reveal factors related to suicidal behavior; however, such studies are lacking in Korea. This study investigated the factors related to suicide using psychological autopsies in Incheon, a major city in Korea. In total, 46 cases were investigated using the Korea-Psychological Autopsy Checklist (K-PAC), and data on mental health conditions and psychosocial factors of suicide decedents and their families were analyzed. It was estimated that 87% of individuals of suicides had a mental health condition before death, but only 15.2% continued treatment or counseling. Most individuals who died of suicide showed warning signs before death, but only 19.6% of survivors of suicide loss noticed them. Mental health concerns before and after the death of the individual were also identified in more than half of their families. To prevent suicide, intensive and continuous treatment for psychiatric conditions and prompt recognition of active response to suicide warning signs are required. Care for the mental health of family members is also important.
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Suicidio , Autopsia , Humanos , República de Corea/epidemiología , Factores de Riesgo , Ideación Suicida , Suicidio/psicología , SobrevivientesRESUMEN
BACKGROUND: Although there are some controversies regarding whole pelvic radiation therapy (WPRT) due to its gastrointestinal and hematologic toxicities, it is considered for patients with gynecological, rectal, and prostate cancer. To effectively spare organs-at-risk (OAR) doses using multi-leaf collimator (MLC)'s optimal segments, potential dosimetric benefits in volumetric modulated arc therapy (VMAT) using a half-beam technique (HF) were investigated for WPRT. METHODS: While the size of a fully opened field (FF) was decided to entirely include a planning target volume in all beam's eye view across arc angles, the HF was designed to use half the FF from the isocenter for dose optimization. The left or the right half of the FF was alternatively opened in VMAT-HF using a pair of arcs rotating clockwise and counterclockwise. Dosimetric benefits of VMAT-HF, presented with dose conformity, homogeneity, and dose-volume parameters in terms of modulation complex score, were compared to VMAT optimized using the FF (VMAT-FF). Consequent normal tissue complication probability (NTCP) by reducing the irradiated volumes was evaluated as well as dose-volume parameters with statistical analysis for OAR. Moreover, beam-on time and MLC position precision were analyzed with log files to assess plan deliverability and clinical applicability of VMAT-HF as compared to VMAT-FF. RESULTS: While VMAT-HF used 60%-70% less intensity modulation complexity than VMAT-FF, it showed superior dose conformity. The small intestine and colon in VMAT-HF showed a noticeable reduction in the irradiated volumes of up to 35% and 15%, respectively, at an intermediate dose of 20-45 Gy. The small intestine showed statistically significant dose sparing at the volumes that received a dose from 15 to 45 Gy. Such a dose reduction for the small intestine and colon in VMAT-HF presented a significant NTCP reduction from that in VMAT-FF. Without sacrificing the beam delivery efficiency, VMAT-HF achieved effective OAR dose reduction in dose-volume histograms. CONCLUSIONS: VMAT-HF led to deliver conformal doses with effective gastrointestinal-OAR dose sparing despite using less modulation complexity. The dose of VMAT-HF was delivered with the same beam-on time with VMAT-FF but precise MLC leaf motions. The VMAT-HF potentially can play a valuable role in reducing OAR toxicities associated with WPRT.
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Zika virus (ZIKV), which is associated with severe diseases in humans, has spread rapidly and globally since its emergence. ZIKV and dengue virus (DENV) are closely related, and antibody-dependent enhancement (ADE) of infection between cocirculating ZIKV and DENV may exacerbate disease. Despite these serious threats, there are currently no approved antiviral drugs against ZIKV and DENV. The NS2B-NS3 viral protease is an attractive antiviral target because it plays a pivotal role in polyprotein cleavage, which is required for viral replication. Thus, we sought to identify novel inhibitors of the NS2B-NS3 protease. To that aim, we performed structure-based virtual screening using 467,000 structurally diverse chemical compounds. Then, a fluorescence-based protease inhibition assay was used to test whether the selected candidates inhibited ZIKV protease activity. Among the 123 candidate inhibitors selected from virtual screening, compound 1 significantly inhibited ZIKV NS2B-NS3 protease activity in vitro. In addition, compound 1 effectively inhibited ZIKV and DENV infection of human cells. Molecular docking analysis suggested that compound 1 binds to the NS2B-NS3 protease of ZIKV and DENV. Thus, compound 1 could be used as a new therapeutic option for the development of more potent antiviral drugs against both ZIKV and DENV, reducing the risks of ADE.
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Eudebeiolide B is a eudesmane-type sesquiterpenoid compound isolated from Salvia plebeia R. Br., and little is known about its biological activity. In this study, we investigated the effects of eudebeiolide B on osteoblast differentiation, receptor activator nuclear factor-κB ligand (RANKL)-induced osteoclastogenesis in vitro and ovariectomy-induced bone loss in vivo. Eudebeiolide B induced the expression of alkaline phosphatase (ALP) and calcium accumulation during MC3T3-E1 osteoblast differentiation. In mouse bone marrow macrophages (BMMs), eudebeiolide B suppressed RANKL-induced osteoclast differentiation of BMMs and bone resorption. Eudebeiolide B downregulated the expression of nuclear factor of activated T-cells 1 (NFATc1) and c-fos, transcription factors induced by RANKL. Moreover, eudebeiolide B attenuated the RANKL-induced expression of osteoclastogenesis-related genes, including cathepsin K (Ctsk), matrix metalloproteinase 9 (MMP9) and dendrocyte expressed seven transmembrane protein (DC-STAMP). Regarding the molecular mechanism, eudebeiolide B inhibited the phosphorylation of Akt and NF-κB p65. In addition, it downregulated the expression of cAMP response element-binding protein (CREB), Bruton's tyrosine kinase (Btk) and phospholipase Cγ2 (PLCγ2) in RANKL-induced calcium signaling. In an ovariectomized (OVX) mouse model, intragastric injection of eudebeiolide B prevented OVX-induced bone loss, as shown by bone mineral density and contents, microarchitecture parameters and serum levels of bone turnover markers. Eudebeiolide B not only promoted osteoblast differentiation but inhibited RANKL-induced osteoclastogenesis through calcium signaling and prevented OVX-induced bone loss. Therefore, eudebeiolide B may be a new therapeutic agent for osteoclast-related diseases, including osteoporosis, rheumatoid arthritis and periodontitis.
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Coronavirus disease 2019 (COVID-19), which causes serious respiratory illness such as pneumonia and lung failure, was first reported in Wuhan, the capital of Hubei, China. The etiological agent of COVID-19 has been confirmed as a novel coronavirus, now known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is most likely originated from zoonotic coronaviruses, like SARS-CoV, which emerged in 2002. Within a few months of the first report, SARS-CoV-2 had spread across China and worldwide, reaching a pandemic level. As COVID-19 has triggered enormous human casualties and serious economic loss posing global threat, an understanding of the ongoing situation and the development of strategies to contain the virus's spread are urgently needed. Currently, various diagnostic kits to test for COVID-19 are available and several repurposing therapeutics for COVID-19 have shown to be clinically effective. In addition, global institutions and companies have begun to develop vaccines for the prevention of COVID-19. Here, we review the current status of epidemiology, diagnosis, treatment, and vaccine development for COVID-19.
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Betacoronavirus , Técnicas de Laboratorio Clínico , Infecciones por Coronavirus , Pandemias , Neumonía Viral , Vacunas Virales , Betacoronavirus/inmunología , COVID-19 , Prueba de COVID-19 , Vacunas contra la COVID-19 , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/tratamiento farmacológico , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/inmunología , Infecciones por Coronavirus/prevención & control , Infecciones por Coronavirus/terapia , Humanos , Neumonía Viral/diagnóstico , Neumonía Viral/epidemiología , Neumonía Viral/inmunología , Neumonía Viral/terapia , SARS-CoV-2 , Tratamiento Farmacológico de COVID-19RESUMEN
Oleanolic acid acetate (OAA), a major triterpenoid compound of Vigna angularis (azuki bean, V. angularis), has been shown to downregulate inflammatory responses in macrophages. Here, we show the molecular basis for the effect of OAA on Toll-like receptor (TLR) downstream signaling. OAA treatment significantly inhibited the secretion of embryonic alkaline phosphatase (SEAP) induced by polyinosinic acid (poly(I), TLR3 ligand) in a dose-dependent manner and without cytotoxicity in THP1-XBlue cells. In addition, OAA downregulated the gene expression of poly(I) induced pro-inflammatory cytokines and chemokines genes such as MCP-1, IL-1ß, IL-8, VCAM-1 and ICAM-1. Furthermore, we found that the inhibition activity of OAA was accompanied by decreased activation of not only nuclear factor-kappa B (NF-κB) signaling but also mitogen-activated protein kinase (MAPK) signaling upon stimulation with the TLR3 agonist. Interestingly, the interaction of OAA with IκB kinase α/ß (IKKα/ß) strongly attenuated the production of certain proteins and inflammatory cytokines in the TLR3 signaling pathway, such as nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha (IkBα), extracellular regulated kinases (ERK), and p38, in an in vitro model. The action of OAA was regulated by TLR3, demonstrating that TLR3 plays a critical role in mediating the physiologically-relevant anti-inflammatory action of OAA and that the interaction with IKKα/ß is modulated through TLR3. These results reveal new insight into the understanding of the regulatory mechanisms of the downstream TLR3 signaling pathway and consequent inflammatory responses that are involved in the development and progression of inflammatory diseases.
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Acetatos/farmacología , Antiinflamatorios/farmacología , Quinasa I-kappa B/metabolismo , Inflamación/tratamiento farmacológico , FN-kappa B/metabolismo , Ácido Oleanólico/farmacología , Receptor Toll-Like 3/metabolismo , Línea Celular , Citocinas/metabolismo , Regulación hacia Abajo/efectos de los fármacos , Expresión Génica/efectos de los fármacos , Humanos , Inflamación/metabolismo , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Transducción de Señal/efectos de los fármacosRESUMEN
INTRODUCTION: The aim of this study was to investigate biological changes in tissues with muscle contusion after the application of high frequency (HF) electromagnetic wave. METHODS: An acrylic pipe was placed on the right hind limb and a metallic ball was dropped inside the pipe, which resulted in a muscle contusion. After acquiring the optimal condition for muscle contusion, 20 Sprague-Dawley rats were allocated to the HF treatment (Nâ¯=â¯10) and sham groups (Nâ¯=â¯10), which then underwent muscle contusion injury at their right thigh. The thickness and circumference of the right thigh and the left thigh (negative control groups) were measured (day 0). HF electromagnetic wave stimulation for three days was performed on the contusion area in the HF group after one day. Thickness was measured at the thickest area of both hind limbs and the circumference was measured every day for three days. The sham group received no treatment, and the circumference and thickness were measured using the same method. After three days, Hematoxylin and eosin and immunohistochemical (IHC) staining for IL-1ß were performed and TUNEL assay was conducted for apoptosis in the skin and muscle layers. RESULTS: The thigh muscle thickness at day 1 was significantly different between groups (Pâ¯=â¯0.018) and this difference was observed between both sham and control groups (corrected Pâ¯=â¯0.007), and between sham and HF groups (corrected Pâ¯=â¯0.043). Thigh circumference was significantly different at day 3 (Pâ¯=â¯0.047) and this difference was found between sham and control groups (corrected Pâ¯=â¯0.018), and between sham and HF groups (corrected Pâ¯=â¯0.032). In the HF group, the inflammatory response was reduced to almost the same level as the control group. Evaluation of IL-1ß level, the inflammatory cytokine, through IHC showed marked localization of IL-1ß in muscle fibers of the sham group. However, significantly less IL-1ß was observed in the muscle of the HF treatment group. There was neither injury nor apoptosis after HF stimulation. CONCLUSIONS: Application of the HF showed therapeutic effect on muscle contusion by reducing muscle swelling. This effect might be caused by the anti-inflammatory action of the HF, which evoked energy into the injured muscle.
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Contusiones/patología , Modelos Animales de Enfermedad , Radiación Electromagnética , Inflamación/inmunología , Interleucina-1beta/metabolismo , Músculo Esquelético/patología , Animales , Contusiones/inmunología , Contusiones/radioterapia , Fenómenos Electromagnéticos , Inflamación/radioterapia , Interleucina-1beta/efectos de la radiación , Masculino , Músculo Esquelético/inmunología , Músculo Esquelético/efectos de la radiación , Ratas , Ratas Sprague-Dawley , Transducción de SeñalRESUMEN
The interleukin-6 (IL-6) family of cytokines plays a key role in the pathogenesis of rheumatoid arthritis and osteoporosis through the regulation of bone formation and resorption. In this study, it was observed that ethanol extract of Salvia plebeia R.Br. (S.P-EE) inhibited IL-6-induced signaling cascade including phosphorylation of JAK2/STAT3 and ERK. Subsequently, it was examined whether S.P-EE treatment could recover bone loss in ovariectomized (OVX) mice. Indeed, S.P-EE exhibited both preventive and therapeutic effect on OVX-induced bone loss in trabecular microarchitecture along with significant increase in bone mineral density and content. To understand the mechanism of action of S.P-EE in bone metabolism, the effect of S.P-EE on osteoclast differentiation and activity was investigated. S.P-EE significantly inhibited RANKL-induced osteoclast differentiation by suppressing phosphorylation of MAPK and Akt, and expression of NFATc1 and osteoclast marker genes. S.P-EE also inhibited bone-resorbing activity of osteoclasts. Furthermore, isolation and identification of the active compounds which are responsible for the inhibitory effect of S.P-EE on osteoclast differentiation was carried out. Six major flavonoids and plebeiolide A-C were isolated and examined their effects on osteoclast differentiation. Luteolin and hispidulin, and plebeiolide A and C, not B exhibited potent inhibitory activity on RANKL-induced osteoclast formation.
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Resorción Ósea/prevención & control , Interleucina-6/antagonistas & inhibidores , Osteogénesis/efectos de los fármacos , Ovariectomía/efectos adversos , Extractos Vegetales/uso terapéutico , Salvia , Animales , Resorción Ósea/etiología , Resorción Ósea/metabolismo , Células Cultivadas , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Interleucina-6/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos ICR , Osteogénesis/fisiología , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiologíaRESUMEN
Seven eudesmane-type sesquiterpenoid lactones and the known plebeiolide C were isolated from an ethanol-soluble extract of the aerial parts of Salvia plebeia R. Br. Their structures were determined via NMR and MS, and their absolute configurations were elucidated using ECD, and X-ray crystallographic analysis, as well as the modified Mosher ester method. All isolates were evaluated for their inhibitory effects on IL6-induced STAT3 promoter activation in stably transfected Hep3B cells. Of these isolates, eudebeiolide D exhibited an inhibitory effect with the IC50 value of 1.1 µM.
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Medicamentos Herbarios Chinos/aislamiento & purificación , Medicamentos Herbarios Chinos/farmacología , Interleucina-6/farmacología , Lactonas/aislamiento & purificación , Lactonas/farmacología , Factor de Transcripción STAT3/efectos de los fármacos , Salvia/química , Sesquiterpenos de Eudesmano/aislamiento & purificación , Sesquiterpenos de Eudesmano/farmacología , Cristalografía por Rayos X , Medicamentos Herbarios Chinos/química , Concentración 50 Inhibidora , Lactonas/química , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Componentes Aéreos de las Plantas/química , Sesquiterpenos de Eudesmano/químicaRESUMEN
A reproducible analytical method using reverse-phase high liquid performance chromatography combined with UV detecting was developed for the quantitative determination of four compounds isolated from the ethanol extract of Phaseolus angularis seeds (PASE): oleanolic acid (1), oleanolic acid acetate (2), stigmasterol (3) and ß-sitosterol (4). This method was fully validated in terms of linearity (r2 > 0.999), accuracy (98.5%-100.8%), precision (<0.92%), LOD (<0.0035 mg/mL), and LOQ (<0.0115 mg/mL). The effects of the PASE and isolated compounds 1-4 on TLR4 activation were tested in THP1-Blue cells. Among the tested substances, compound 2 showed potent inhibitory activity with an IC50 value of 3.89 ± 0.17 µM.
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Phaseolus/química , Fitosteroles/química , Semillas/química , Triterpenos/química , Cromatografía Líquida de Alta Presión , Concentración 50 Inhibidora , Fitosteroles/aislamiento & purificación , Fitosteroles/farmacología , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Receptor Toll-Like 4/antagonistas & inhibidores , Triterpenos/aislamiento & purificación , Triterpenos/farmacologíaRESUMEN
PURPOSE: The degree of radiation-induced lung fibrosis (RILF) can be measured quantitatively by fibrosis volume (VF) on chest computed tomography (CT) scan. The purpose of this study was to investigate the interobserver and intraobserver variability in CT-based measurement of VF. MATERIALS AND METHODS: We selected 10 non-small cell lung cancer patients developed with RILF after postoperative radiation therapy (PORT) and delineated VF on the follow-up chest CT scanned at more than 6 months after radiotherapy. Three radiation oncologists independently delineated VF to investigate the interobserver variability. Three times of delineation of VF was performed by two radiation oncologists for the analysis of intraobserver variability. We analysed the concordance index (CI) and inter/intraclass correlation coefficient (ICC). RESULTS: The median CI was 0.61 (range, 0.44 to 0.68) for interobserver variability and the median CIs for intraobserver variability were 0.69 (range, 0.65 to 0.79) and 0.61(range, 0.55 to 0.65) by two observers. The ICC for interobserver variability was 0.974 (p < 0.001) and ICCs for intraobserver variability were 0.996 (p < 0.001) and 0.991 (p < 0.001), respectively. CONCLUSION: CT-based measurement of VF with patients who received PORT was a highly consistent and reproducible quantitative method between and within observers.
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Nitric oxide (NO) is recognized as a mediator and regulator of inflammatory responses. NO is produced by nitric oxide synthase (NOS), and NOS is abundantly expressed in the human dental pulp cells (HDPCs). NO produced by NOS can be cytotoxic at higher concentrations to HDPCs. However, the mechanism by which this cytotoxic pathway is activated in cells exposed to NO is not known. The purpose of this study was to elucidate the NO-induced cytotoxic mechanism in HDPCs. Sodium nitroprusside (SNP), a NO donor, reduced the viability of HDPCs in a dose- and time-dependent manner. We investigated the in vitro effects of nitric oxide on apoptosis of cultured HDPCs. Cells showed typical apoptotic morphology after exposure to SNP. Besides, the number of Annexin V positive cells was increased among the SNP-treated HDPCs. SNP enhanced the production of reactive oxygen species (ROS), and N-acetylcysteine (NAC) ameliorated the decrement of cell viability induced by SNP. However, a soluble guanylate cyclase inhibitor (ODQ) did not inhibited the decrement of cell viability induced by SNP. SNP increased cytochrome c release from the mitochondria to the cytosol and the ratio of Bax/Bcl-2 expression levels. Moreover, SNP-treated HDPCs elevated activities of caspase-3 and caspase-9. While pretreatment with inhibitors of caspase (z-VAD-fmk, z-DEVD-fmk) reversed the NO-induced apoptosis of HDPCs. From these results, it can be suggested that NO induces apoptosis of HDPCs through the mitochondria-dependent pathway mediated by ROS and Bcl-2 family, but not by the cyclic GMP pathway.
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Energy and glucose homeostasis are regulated by central serotonin 2C receptors. These receptors are attractive pharmacological targets for the treatment of obesity; however, the identity of the serotonin 2C receptor-expressing neurons that mediate the effects of serotonin and serotonin 2C receptor agonists on energy and glucose homeostasis are unknown. Here, we show that mice lacking serotonin 2C receptors (Htr2c) specifically in pro-opiomelanocortin (POMC) neurons had normal body weight but developed glucoregulatory defects including hyperinsulinemia, hyperglucagonemia, hyperglycemia, and insulin resistance. Moreover, these mice did not show anorectic responses to serotonergic agents that suppress appetite and developed hyperphagia and obesity when they were fed a high-fat/high-sugar diet. A requirement of serotonin 2C receptors in POMC neurons for the maintenance of normal energy and glucose homeostasis was further demonstrated when Htr2c loss was induced in POMC neurons in adult mice using a tamoxifen-inducible POMC-cre system. These data demonstrate that serotonin 2C receptor-expressing POMC neurons are required to control energy and glucose homeostasis and implicate POMC neurons as the target for the effect of serotonin 2C receptor agonists on weight-loss induction and improved glycemic control.
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Metabolismo Energético/fisiología , Glucosa/metabolismo , Homeostasis/fisiología , Neuronas/fisiología , Proopiomelanocortina/fisiología , Receptor de Serotonina 5-HT2C/fisiología , Animales , Depresores del Apetito/farmacología , Peso Corporal , Grasas de la Dieta/toxicidad , Sacarosa en la Dieta/toxicidad , Resistencia a Medicamentos , Conducta Alimentaria/efectos de los fármacos , Femenino , Glucagón/sangre , Glucagón/metabolismo , Hiperglucemia/genética , Hiperglucemia/metabolismo , Hiperinsulinismo/genética , Hiperinsulinismo/metabolismo , Hiperfagia/etiología , Insulina/metabolismo , Resistencia a la Insulina , Secreción de Insulina , Masculino , Ratones , Ratones Noqueados , Obesidad/etiología , Proopiomelanocortina/biosíntesis , Proopiomelanocortina/genética , Receptor de Serotonina 5-HT2C/deficiencia , Receptor de Serotonina 5-HT2C/genética , Proteínas Recombinantes de Fusión/biosíntesis , Serotonina/fisiología , Agonistas de Receptores de Serotonina/farmacologíaRESUMEN
Aberrant expression of apurinic-apyrimidinic endonuclease-1 (APEX1) has been reported in numerous human solid tumors and is positively correlated with cancer progression; however, the role of APEX1 in tumor progression is poorly defined. Here, we show that APEX1 contributes to aggressive colon cancer behavior and functions as an upstream activator in the Jagged1/Notch signaling pathway. APEX1 overexpression or knockdown in human colon cancer cell lines induced profound changes in malignant properties such as cell proliferation, anchorage-independent growth, migration, invasion, and angiogenesis in vitro and in tumor formation and metastasis in mouse xenograft models. These oncogenic effects of APEX1 were mediated by the upregulation of Jagged1, a major Notch ligand. Furthermore, APEX1 expression was associated with Jagged1 in various colon cancer cell lines and in tissues from colon cancer patients. This finding identifies APEX1 as a positive regulator of Jagged1/Notch activity and suggests that it is a potential therapeutic target in colon cancers that exhibit high levels of Jagged1/Notch signaling.
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BACKGROUND: Localization of the tumor bed of breast cancer is crucial for accurate planning of boost irradiation. Lumpectomy cavity and surgical clips provide localizing information about tumor bed. However, defining the tumor bed is often difficult because of presence of unclear lumpectomy cavity and lack of certain information such as absence of surgical clips. In the present study, we evaluated the feasibility of initial diagnostic PET-CT in localization of the tumor bed using deformable image registration (DIR). METHODS: We selected twenty-five patients who had an initial diagnostic PET-CT performed and underwent breast-conserving surgery with surgical clips in tumor bed. In every individual patient, two target volumes were separately delineated on planning CT; 1) target volume based on surgical clips with a margin of 1 cm (TV(clip)) and 2) tumor volume based on 90% of maximum SUV on PET-CT registered by DIR (TV(PET)). The percent of TV(PET) in TV(clip) (V(in)) was calculated and distance between center points of two volumes (D(center)) was also measured. RESULTS: Mean D(center) between two volumes was 1.4 cm (range, 0.33-2.53). Mean V(in) was 94.8% (range, 60.9-100) and 100% in 18 out of 25 patients. When compared to the center of TV(clip), the center of TV(PET) tended to be located posteriorly (mean 0.3 cm, standard deviation 0.6), laterally (mean 0.3 cm, standard deviation 0.8) and inferiorly (mean 0.4 cm, standard deviation 0.9). CONCLUSION: Initial diagnostic PET-CT can be one of the possible references to localize the tumor bed in breast cancer radiotherapy.
Asunto(s)
Neoplasias de la Mama/patología , Neoplasias de la Mama/radioterapia , Imagen Multimodal/métodos , Planificación de la Radioterapia Asistida por Computador/métodos , Adenocarcinoma Mucinoso/patología , Adenocarcinoma Mucinoso/radioterapia , Adenocarcinoma Mucinoso/cirugía , Adulto , Anciano , Neoplasias de la Mama/cirugía , Carcinoma Ductal de Mama/patología , Carcinoma Ductal de Mama/radioterapia , Carcinoma Ductal de Mama/cirugía , Estudios de Factibilidad , Femenino , Humanos , Mastectomía Segmentaria , Persona de Mediana Edad , Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos XRESUMEN
Embryonic hypoxia/ischemia is a major cause of a poor fetal outcome and future neonatal and adult handicaps. However, biochemical cellular events in mouse embryonic stem (mES) cells during hypoxia remains unclear. This study investigated the underlying mechanism of apoptosis in mES cells under CoCl2-induced hypoxic/ischemic conditions. CoCl2 enhanced the expression of hypoxia-inducible factor-1α (HIF-1α) and the accumulation of reactive oxygen species in mES cells. The CoCl2-treated mES cells showed a decrease in cell viability as well as typical apoptotic changes, cell shrinkage, chromatin condensation, and nuclear fragmentation and an extended G2/M phase of the cell cycle. CoCl2 augmented the release of cytochrome c into the cytosol from the mitochondria with a concomitant loss of the mitochondrial transmembrane potential (ΔΨm) and upregulated the voltage-dependent anion channel. In addition, CoCl2-induced caspase-3, -8, and -9 activation and upregulation of p53 level, whereas downregulated Bcl-2 and Bcl-xL, a member of the anti-apoptotic Bcl-2 family in mES cells. Furthermore, CoCl2 led to the upregulation of Fas and Fas-ligand, which are the death receptor assemblies, as well as the cleavage of Bid in mES cells. These results suggest that CoCl2 induces apoptosis through both mitochondria- and death receptor-mediated pathways that are regulated by the Bcl-2 family in mES cells.
Asunto(s)
Apoptosis , Cobalto/farmacología , Células Madre Embrionarias/fisiología , Mitocondrias/fisiología , Receptores de Muerte Celular/metabolismo , Animales , Caspasas/metabolismo , Hipoxia de la Célula , Citocromos c/metabolismo , Células Madre Embrionarias/efectos de los fármacos , Proteína Ligando Fas/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Potencial de la Membrana Mitocondrial , Ratones , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal , Activación Transcripcional , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Receptor fas/metabolismoRESUMEN
PURPOSE: Parotid gland can be considered as a risk organ in whole brain radiotherapy (WBRT). The purpose of this study is to evaluate the parotid gland sparing effect of computed tomography (CT)-based WBRT compared to 2-dimensional plan with conventional field margin. MATERIALS AND METHODS: From January 2008 to April 2011, 53 patients underwent WBRT using CT-based simulation. Bilateral two-field arrangement was used and the prescribed dose was 30 Gy in 10 fractions. We compared the parotid dose between 2 radiotherapy plans using different lower field margins: conventional field to the lower level of the atlas (CF) and modified field fitted to the brain tissue (MF). RESULTS: Averages of mean parotid dose of the 2 protocols with CF and MF were 17.4 Gy and 8.7 Gy, respectively (p < 0.001). Mean parotid dose of both glands ≥20 Gy were observed in 15 (28.3%) for CF and in 0 (0.0%) for MF. The whole brain percentage volumes receiving >98% of prescribed dose were 99.7% for CF and 99.5% for MF. CONCLUSION: Compared to WBRT with CF, CT-based lower field margin modification is a simple and effective technique for sparing the parotid gland, while providing similar dose coverage of the whole brain.
RESUMEN
Microbial characteristics of a fixed-biofilm process packed with hollow-type ceramic media were studied for treating low organic level sewage (average TCOD/NH4(+)-N ratio = 3.4), and an easy monitoring method such as a bio-index was suggested. The fractions of autotrophs and heterotrophs were directly affected by changing the organic surface loads in the aerobic reactors. After 90 days of operation, the amount of attached biomass was maintained constantly with a stable nitrification rate and low effluent NH4(+)-N concentration. At this point, the dominant diatoms observed were Fragilaria sp. in the second anoxic reactor, Cyclotella sp. in the second anoxic and aerobic reactors, and Navicula sp. in the first aerobic reactor. Specific protozoa (Euglypha sp., Arcella sp. and Colepus sp.), which were considered predators of nitrifiers, were observed under high nitrification rate and were used as a bio-index and indicators of nitrifying biofilm formation and low effluent NH4(+)-N concentration in the fixed-biofilm BNR process.