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Aspirin hypersensitivity continues to be a major clinical challenge in patients with coronary artery disease (CAD), particularly in those requiring percutaneous coronary intervention (PCI) in the absence of a validated alternative antiplatelet regimen. Although true aspirin allergies are uncommon, they can manifest with severe reactions such as angioedema or anaphylaxis, highlighting the critical role of diagnostic challenge tests and tolerance induction strategies. Here, a 61-year-old female with end-stage renal disease (ESRD) on hemodialysis presented with new-onset heart failure and elevated troponins in the setting of a hypertensive emergency. A subsequent left heart catheterization revealed severe multivessel disease, but PCI was deferred due to her history suggestive of aspirin-induced angioedema and the absence of a known optimal approach in this scenario. Given the feasibility of completing a desensitization protocol, aspirin desensitization was pursued, facilitating the successful placement of a drug-eluting stent. This case highlights the need for validated protocols to manage aspirin hypersensitivity, as the current treatment paradigm necessitates a highly individualized approach by the treating clinician.
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The use of the antimalarial drug hydroxychloroquine is a standard treatment in patients with systemic lupus erythematosus. It helps reduce disease-associated damage, prevents disease flare, and improves overall survival. The mechanism of action of hydroxychloroquine includes interference with lysosomal degradation of cells leading to the accumulation of vacuoles. Retinopathy is a well-described adverse effect of hydroxychloroquine, thus requiring screening with an ophthalmologist after prolonged use. Although rarely reported, cardiac adverse effects of hydroxychloroquine can also occur. In this report, we present a case of a 23-year-old woman with systemic lupus erythematosus on hydroxychloroquine who presented with stroke possibly due to Libman-Sacks endocarditis and was found to have severe hypertrophic cardiomyopathy on transthoracic echocardiogram.
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BACKGROUND: Hyperoxia is a well-known cause of cerebral white matter injury in preterm infants with male sex being an independent and critical risk factor for poor neurodevelopmental outcome. Sex is therefore being widely considered as one of the major decisive factors for prognosis and treatment of these infants. But unfortunately, we still lack a clear view of the molecular mechanisms that lead to such a profound difference. Hence, using mouse-derived primary oligodendrocyte progenitor cells (OPCs), we investigated the molecular factors and underlying mechanisms behind the differential response of male and female cells towards oxidative stress. RESULTS: We demonstrate that oxidative stress severely affects cellular functions related to energy metabolism, stress response, and maturation in the male-derived OPCs, whereas the female cells remain largely unaffected. CNPase protein level was found to decline following hyperoxia in male but not in female cells. This impairment of maturation was accompanied by the downregulation of nucleoporin and nuclear lamina proteins in the male cells. We identify Nup133 as a novel target protein affected by hyperoxia, whose inverse regulation may mediate this differential response in the male and female cells. Nup133 protein level declined following hyperoxia in male but not in female cells. We show that nuclear respiratory factor 1 (Nrf1) is a direct downstream target of Nup133 and that Nrf1 mRNA declines following hyperoxia in male but not in female cells. The female cells may be rendered resistant due to synergistic protection via the estrogen receptor alpha (ERα) which was upregulated following hyperoxia in female but not in male cells. Both Nup133 and ERα regulate mitochondrial function and oxidative stress response by transcriptional regulation of Nrf1. CONCLUSIONS: These findings from a basic cell culture model establish prominent sex-based differences and suggest a novel mechanism involved in the differential response of OPCs towards oxidative stress. It conveys a strong message supporting the need to study how complex cellular processes are regulated differently in male and female brains during development and for a better understanding of how the brain copes up with different forms of stress after preterm birth.
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Patients with glioblastoma multiforme (GBM) suffer from an increased incidence of vascular thrombotic events. However, key influencing factors of the primary hemostasis have not been characterized in GBM patients to date. Thus, the present study determines the activation level of circulating platelets in GBM patients, in-vitro reactivity to agonist-induced platelet stimulation and the formation of circulating platelet-leucocyte conjugates as well as the plasma levels of the proinflammatory lipid mediator sphingosine-1-phosphate (S1P). The endogenous thrombin potential (ETP) was determined as global marker for hemostasis. The 21 GBM patients and 21 gender and age matched healthy individuals enrolled in this study did not differ in mean total platelet count. Basal surface expression of platelet CD63 determined by flow cytometry was significantly increased in GBM patients compared to controls as was observed for the concentration of soluble P-selectin in the plasma of GBM patients. While the ETP was not affected, the immunomodulatory lipid S1P was significantly decreased in peripheral blood in GBM. Interestingly, monocyte expression of PSGL-1 (CD162) was decreased in GBM patient blood, possibly explaining the rather decreased formation of platelet-monocyte conjugates. Our study reveals an increased CD63 expression and P-selectin expression/ secretion of circulating platelets in GBM patients. In parallel a down-modulated PSGL-1 expression in circulating monocytes and a trend towards a decreased formation of heterotypic platelet-monocyte conjugates in GBM patients was seen. Whether this and the observed decreased plasma level of the immunomodulatory S1P reflects a systemic anti-inflammatory status needs to be addressed in future studies.
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Hepatocellular carcinoma (HCC) is a frequent and deadly disease worldwide. The absence of effective therapies when the tumor is surgically unresectable leads to an extremely poor outcome of HCC patients. Thus, it is mandatory to elucidate the molecular pathogenesis of HCC in order to develop novel therapeutic strategies against this pernicious tumor. Mounting evidence indicates that suppression of the DNA damage response machinery might be deleterious for the survival and growth of the tumor cells. In particular, DNA dependent protein kinase catalytic subunit (DNA-PKcs), a major player in the non-homologous end-joining (NHEJ) repair process, seems to represent a valuable target for innovative anti-neoplastic therapies in cancer. DNA-PKcs levels are strongly upregulated and associated with a poor clinical outcome in various tumor types, including HCC. Importantly, DNA-PKcs not only protects tumor cells from harmful DNA insults coming either from the microenvironment or chemotherapeutic drug treatments, but also possesses additional properties, independent from its DNA repair activity, that provide growth advantages to cancer cells. These properties (metabolic and gene reprogramming, invasiveness and metastasis, resistance to apoptosis, etc.) have started to be elucidated. In the present review, we summarize the physiologic and oncogenic roles of DNA-PKcs, with a special emphasis on liver cancer. In particular, this work focuses on the molecular mechanism whereby DNA-PKcs exerts its pro-tumorigenic activity in cancer cells. In addition, the upstream regulator of DNA-PKcs activation as well as its downstream effectors thus far identified are illustrated. Furthermore, the potential therapeutic strategies aimed at inhibiting DNA-PKcs activity in HCC are discussed.
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Carcinoma Hepatocelular/genética , Reparo do DNA por Junção de Extremidades/efeitos dos fármacos , DNA de Neoplasias/genética , Proteína Quinase Ativada por DNA/antagonistas & inibidores , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/genética , Proteínas Nucleares/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Quinase do Ponto de Checagem 2/genética , Quinase do Ponto de Checagem 2/metabolismo , Cromonas/uso terapêutico , Quebras de DNA de Cadeia Dupla , Dano ao DNA , DNA de Neoplasias/metabolismo , Proteína Quinase Ativada por DNA/genética , Proteína Quinase Ativada por DNA/metabolismo , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Terapia de Alvo Molecular , Morfolinas/uso terapêutico , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Transdução de Sinais , Tiofenos/uso terapêutico , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Quinase 1 Polo-LikeRESUMO
BACKGROUND & AIMS: Cumulating evidence underlines the crucial role of aberrant lipogenesis in human hepatocellular carcinoma (HCC). Here, we investigated the oncogenic potential of fatty acid synthase (FASN), the master regulator of de novo lipogenesis, in the mouse liver. METHODS: FASN was overexpressed in the mouse liver, either alone or in combination with activated N-Ras, c-Met, or SCD1, via hydrodynamic injection. Activated AKT was overexpressed via hydrodynamic injection in livers of conditional FASN or Rictor knockout mice. FASN was suppressed in human hepatoma cell lines via specific small interfering RNA. RESULTS: Overexpression of FASN, either alone or in combination with other genes associated with hepatocarcinogenesis, did not induce histological liver alterations. In contrast, genetic ablation of FASN resulted in the complete inhibition of hepatocarcinogenesis in AKT-overexpressing mice. In human HCC cell lines, FASN inactivation led to a decline in cell proliferation and a rise in apoptosis, which were paralleled by a decrease in the levels of phosphorylated/activated AKT, an event controlled by the mammalian target of rapamycin complex 2 (mTORC2). Downregulation of AKT phosphorylation/activation following FASN inactivation was associated with a strong inhibition of rapamycin-insensitive companion of mTOR (Rictor), the major component of mTORC2, at post-transcriptional level. Finally, genetic ablation of Rictor impaired AKT-driven hepatocarcinogenesis in mice. CONCLUSIONS: FASN is not oncogenic per se in the mouse liver, but is necessary for AKT-driven hepatocarcinogenesis. Pharmacological blockade of FASN might be highly useful in the treatment of human HCC characterized by activation of the AKT pathway.
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Carcinogênese , Carcinoma Hepatocelular , Ácido Graxo Sintase Tipo I , Neoplasias Hepáticas , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Apoptose/fisiologia , Carcinogênese/genética , Carcinogênese/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Ácido Graxo Sintase Tipo I/genética , Ácido Graxo Sintase Tipo I/metabolismo , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Fígado/metabolismo , Fígado/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Camundongos , Fosforilação , Transdução de Sinais/genéticaRESUMO
In aged humans, stroke is a major cause of disability for which no neuroprotective measures are available. In animal studies of focal ischemia, short-term hypothermia often reduces infarct size. Nevertheless, efficient neuroprotection requires long-term, regulated lowering of whole-body temperature. Previously, we reported that post-stroke exposure to hydrogen sulfide (H(2)S) effectively lowers whole-body temperature and confers neuroprotection in aged animals. In the present study using magnetic resonance imaging, electroencephalogram recording, DNA arrays, reverse transcriptase polymerase chain reaction, western blotting and immunofluorescence, we characterized the central nervous system response to H(2)S-induced hypothermia and report, for the first time, that annexin A1, a major pro-inflammatory protein that is upregulated after stroke, was consistently downregulated in polymorphonuclear cells in the peri-lesional cortex of post-ischemic, aged rat brain after 48 hours of hypothermia induced by exposure to H(2)S. Our data suggest that long-term hypothermia may be a viable clinical approach to protecting the aged brain from cerebral injury. Our findings further suggest that, in contrast to monotherapies that have thus far uniformly failed in clinical practice, hypothermia has pleiotropic effects on brain physiology that may be necessary for effective protection of the brain after stroke.
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Envelhecimento , Anexina A1/biossíntese , Isquemia Encefálica/prevenção & controle , Encéfalo/metabolismo , Sulfeto de Hidrogênio/administração & dosagem , Hipotermia Induzida/métodos , Fagocitose/fisiologia , Envelhecimento/patologia , Animais , Western Blotting , Encéfalo/patologia , Encéfalo/fisiopatologia , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Isquemia Encefálica/fisiopatologia , Modelos Animais de Doenças , Eletroencefalografia , Eletroforese em Gel Bidimensional , Imuno-Histoquímica , Imageamento por Ressonância Magnética , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , RNA/genética , RNA/metabolismo , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Telemetria , Fatores de Tempo , Regulação para CimaRESUMO
The present study identified a novel mechanism of induction of apoptosis in glioblastoma cells by scriptaid - a histone deacetylase (HDAC) inhibitor. Scriptaid reduced glioma cell viability by increasing Jun N-terminal kinase (JNK) activation. Although scriptaid induced activation of both p38MAPK and JNK, it was the inhibition of JNK that attenuated scriptaid-induced apoptosis significantly. Scriptaid also increased the expression of (i) p21 and p27 involved in cell-cycle regulation and (ii) γH2AX associated with DNA damage response in a JNK-dependent manner. Treatment with scriptaid increased Ras activity in glioma cells, and transfection of cells with constitutively active RasV12 further sensitized glioma cells to scriptaid-induced apoptosis. Scriptaid also inhibited telomerase activity independent of JNK. Taken together, our findings indicate that scriptaid (i) induces apoptosis and reduces glioma cell proliferation by elevating JNK activation and (ii) also decreases telomerase activity in a JNK-independent manner.
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Apoptose/efeitos dos fármacos , Hidroxilaminas/farmacologia , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Quinolinas/farmacologia , Telomerase/metabolismo , Acetilação/efeitos dos fármacos , Antracenos/farmacologia , Western Blotting , Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Dano ao DNA , Relação Dose-Resposta a Droga , Ativação Enzimática/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Glioma/genética , Glioma/metabolismo , Glioma/patologia , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/metabolismo , Histonas/metabolismo , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Reação em Cadeia da Polimerase/métodos , Transdução de Sinais/efeitos dos fármacos , Telomerase/antagonistas & inibidores , Telomerase/genética , Proteínas ras/metabolismoRESUMO
We investigated the pro-inflammatory response mediated by TNFalpha in glioblastoma and whether treatment with organoselenium Ebselen (2-phenyl-1,2-benzisoselenazol-3[2H]one) can affect TNFalpha induced inflammatory response. Exposure to TNFalpha increased the expression of pro-inflammatory mediator interleukin IL-6, IL-8, monocyte chemoattractant protein-1 (MCP-1) and cyclooxygenase (COX-2). Treatment with Ebselen abrogated TNFalpha induced increase in pro-inflammatory mediators. Ebselen not only abrogated TNFalpha induced enhanced invasiveness of glioma cells by down-regulating matrix metallo proteinase (MMP-9) and urokinase plasminogen (uPa) activity, but also inhibited glioma cell migration. Treatment with Ebselen also down-regulated the enhanced ROS production of TNFalpha treated glioma cells. In addition, Ebselen induced DNA damage repair signaling response in glioma cells both in the presence and absence of TNFalpha. These studies indicate that together with its known ability to sensitize glioma cell to TNFalpha induced apoptosis, Ebselen can overcome TNFalpha induced pro-inflammatory mediators to prevent a build up of a deleterious pro-inflammatory tumor microenvironment.
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Azóis/farmacologia , Glioblastoma/patologia , Inflamação/tratamento farmacológico , Compostos Organosselênicos/farmacologia , Fator de Necrose Tumoral alfa/farmacologia , Azóis/uso terapêutico , Movimento Celular/efeitos dos fármacos , Reparo do DNA , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Inflamação/induzido quimicamente , Mediadores da Inflamação/análise , Isoindóis , Compostos Organosselênicos/uso terapêuticoRESUMO
Resistance to tumor necrosis factor (TNFalpha)-induced apoptosis in various cancer cells has been attributed to the activation of the transcription factor NF-kappaB. Ebselen (2-phenyl-1,2-benzisoselenazol-3[2H]one)-a selenoorganic compound is known to prevent TNFalpha-mediated NF-kappaB activity. As glioblastoma are resistant to the cytotoxic effect of TNFalpha, we investigated the potential of Ebselen in sensitizing glioma cells to TNFalpha-induced apoptosis. Although treatment with Ebselen reduced viability of glioma cells, cotreatment with TNFalpha enhanced apoptosis further through alteration of TNFalpha-mediated signaling pathways. Sensitization of TNFalpha activated glioma cells to apoptosis by Ebselen involved 2 pathways: (i) abrogation of TNFalpha induced NF-kappaB activation and (ii) induction of Fas-associated death inducing signaling complex (DISC) formation. Ebselen inhibited the prosurvival pathway mediated by NF-kappaB by altering the association of TNF receptor associated factor 2 (TRAF2) with TNFalpha receptor associated death domain (TRADD) in the TNFR1-TRADD-TRAF2 complex -an interaction crucial for mediating NF-kappaB activity. Ebselen also induced the formation of DISC involving Fas, Fas-associated death domain (FADD) and active caspase 8 to transduce apoptotic signals in situations where NF-kappaB function was inhibited. Cotreatment with Ebselen and TNFalpha induced G2/M phase arrest in cell cycle and modulated the expression of molecules involved in cell cycle progression. These results raise the possibility of overcoming resistance to TNFalpha-induced apoptosis by cotreatment with organoselenium Ebselen as a strategy to kill glioma cells.
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Apoptose/efeitos dos fármacos , Azóis/farmacologia , Glioblastoma/tratamento farmacológico , NF-kappa B/antagonistas & inibidores , Compostos Organosselênicos/farmacologia , Fator de Necrose Tumoral alfa/farmacologia , Receptor fas/fisiologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Regulação para Baixo , Proteína de Domínio de Morte Associada a Fas/metabolismo , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Isoindóis , NF-kappa B/genética , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Transdução de Sinais , Proteína de Domínio de Morte Associada a Receptor de TNF/metabolismo , Fator 2 Associado a Receptor de TNF/metabolismoRESUMO
Polyphenol epigallocatechin-3-gallate (EGCG) induced apoptosis in glioma cells by elevating oxidative stress through increased reactive oxygen species (ROS) generation. Signs of apoptosis included altered mitochondrial membrane potential and elevated expression of caspase-3 and cytochrome c. The increase in ROS was concomitant with the decrease in expression of thioredoxin (TRX-1) and ceruloplasmin (CP), mediators associated with protection against oxidative stress. EGCG downregulated the levels of pro-inflammatory cytokine interleukin (IL)-6 and chemokines IL-8, monocyte-chemoattractant protein (MCP)-1 and RANTES. EGCG also decreased the invasive potential of gliomas, possibly by affecting the urokinase plasminogen activator (uPA) and cytoskeletal architecture. Our study indicates that EGCG might serve as an effective therapeutic strategy against glioma as it not only promotes cell death through redox perturbation, but also downregulates the release of pro-inflammatory mediators while concomitantly decreasing the invasive potential of glioma cells.
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Increased free radical activity in gestational diabetes (GDM) can lead to a host of damaging and degenerative maternal and fetal complications. Hence antioxidant levels in blood of GDM mothers and cord blood were estimated. Erythrocyte glutathione (GSH), superoxide dismutase (SOD) and thiobarbituric acid reactive substances (TBARS), plasma vitamins C and E and serum total glutathione-S-transferase (GST), protein thiols and ceruloplasmin (Cp) were estimated spectrophotometrically in maternal blood of age matched controls and mothers with GDM and also in cord blood samples of the above. There was a significant increase in the erythrocytic GSH, serum total GST and protein thiols in GDM maternal blood when compared to controls whereas erythrocytic SOD exhibited a marked decrease in GDM cases. The changes in plasma vitamins C and E, Cp and erythrocytic TBARS in GDM were not significantly different from controls. Cord blood levels of protein thiols were also significantly increased in GDM. No significant changes were observed in the serum Cp and GST levels of the same. Hence, elevated glucose levels can induce oxidative stress in GDM mothers.
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Antioxidantes/análise , Diabetes Gestacional/sangue , Sangue Fetal/química , Peroxidação de Lipídeos , Estresse Oxidativo , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , Feminino , Humanos , Projetos Piloto , Gravidez , Adulto JovemRESUMO
Despite recent advances in understanding molecular mechanisms involved in glioblastoma progression, the prognosis of the most malignant brain tumor continues to be dismal. Because the flavonoid kaempferol is known to suppress growth of a number of human malignancies, we investigated the effect of kaempferol on human glioblastoma cells. Kaempferol induced apoptosis in glioma cells by elevating intracellular oxidative stress. Heightened oxidative stress was characterized by an increased generation of reactive oxygen species (ROS) accompanied by a decrease in oxidant-scavenging agents such as superoxide dismutase (SOD-1) and thioredoxin (TRX-1). Knockdown of SOD-1 and TRX-1 expression by small interfering RNA (siRNA) increased ROS generation and sensitivity of glioma cells to kaempferol-induced apoptosis. Signs of apoptosis included decreased expression of Bcl-2 and altered mitochondrial membrane potential with elevated active caspase-3 and cleaved poly(ADP-ribose) polymerase expression. Plasma membrane potential and membrane fluidity were altered in kaempferol-treated cells. Kaempferol suppressed the expression of proinflammatory cytokine interleukin-6 and chemokines interleukin-8, monocyte chemoattractant protein-1, and regulated on activation, normal T-cell expressed and secreted. Kaempferol inhibited glioma cell migration in a ROS-dependent manner. Importantly, kaempferol potentiated the toxic effect of chemotherapeutic agent doxorubicin by amplifying ROS toxicity and decreasing the efflux of doxorubicin. Because the toxic effect of both kaempferol and doxorubicin was amplified when used in combination, this study raises the possibility of combinatorial therapy whose basis constitutes enhancing redox perturbation as a strategy to kill glioma cells.