RESUMEN
OBJECTIVES: New early first-trimester diagnostic criteria for nonviable pregnancy recommended by the Society of Radiologists in Ultrasound via a multispecialty consensus panel extended the diagnostic size criteria of crown-rump length from 5 to 7 mm for embryos without a heartbeat and mean sac diameter from 16 to 25 mm for "empty" sacs. Our study assessed the potential impact of the new criteria on the number of additional follow-up sonograms these changes would engender. METHODS: A retrospective study of all first-trimester sonograms in women with first trimester bleeding from 1999 to 2008 was conducted. Everyone included in the study had a visible gestational sac in the uterus. There were no pregnancies of unknown location or ectopic pregnancies included in this study cohort. Pregnancy of unknown location was used to describe cases in which there were no signs of pregnancy inside or outside the uterus on transvaginal sonography despite a positive pregnancy test result. A total of 1013 patients met the inclusion criteria. RESULTS: Seven hundred fifty-two patients (74%) had identifiable embryos, and 261 (26%) did not. Of those with an identifiable embryo, 286 (38%) had no detectable embryonic cardiac activity. The breakdown of crown-rump lengths in this group was as follows: 100 measuring less than 5 mm, 36 measuring 5 to 7 mm, and 150 measuring 7 mm or greater. The breakdown of mean sac diameters in those without a visible embryo was as follows: 120 measuring less than 16 mm, 90 measuring 16 to 25 mm, and 51 measuring 25 mm or greater. CONCLUSIONS: When diagnosing a failed pregnancy, there can be no room for error. Only 126 of 1013 early pregnancies threatening to abort (12%) fell into the more conservative zones defined by the new compared to the former size criteria (crown-rump length, 5-7 mm; mean sac diameter, 16-25 mm). Therefore, the potential impact of the new guidelines on follow-up sonograms does not appear inordinate.
Asunto(s)
Aborto Espontáneo/diagnóstico por imagen , Muerte Fetal , Ultrasonografía Prenatal , Estudios de Cohortes , Largo Cráneo-Cadera , Femenino , Humanos , Guías de Práctica Clínica como Asunto , Embarazo , Primer Trimestre del Embarazo , Estudios Retrospectivos , Sociedades MédicasRESUMEN
Pulmonary hypertension (PH) is a devastating disease leading to progressive hypoxemia, right ventricular failure, and death. Hypoxia can play a pivotal role in PH etiology, inducing pulmonary vessel constriction and remodeling. These events lead to increased pulmonary vessel wall thickness, elevated vascular resistance and right ventricular hypertrophy. The current study examined the association of the inflammatory cytokine macrophage migration inhibitory factor (MIF) with chronic lung disease and its role in the development of hypoxia-induced PH. We found that plasma MIF in patients with primary PH or PH secondary to interstitial lung disease (ILD) was significantly higher than in the control group (P = 0.004 and 0.007, respectively). MIF involvement with hypoxia-induced fibroblast proliferation was examined in both a human cell-line and primary mouse cells from wild-type (mifâº/âº) and MIF-knockout (mifâ»/â») mice. In vitro, hypoxia-increased MIF mRNA, extracellular MIF protein accumulation and cell proliferation. Inhibition of MIF inflammatory activity reduced hypoxia-induced cell proliferation. However, hypoxia only increased proliferation of mifâ»/â» cells when they were supplemented with media from mifâº/⺠cells. This growth increase was suppressed by MIF inhibition. In vivo, chronic exposure of mice to a normobaric atmosphere of 10% oxygen increased lung tissue expression of mRNA encoding MIF and accumulation of MIF in plasma. Inhibition of the MIF inflammatory active site, during hypoxic exposure, significantly reduced pulmonary vascular remodeling, cardiac hypertrophy and right ventricular systolic pressure. The data suggest that MIF plays a critical role in hypoxia-induced PH, and its inhibition may be beneficial in preventing the development and progression of the disease.
Asunto(s)
Hipertensión Pulmonar/sangre , Hipoxia/fisiopatología , Factores Inhibidores de la Migración de Macrófagos/sangre , Factores Inhibidores de la Migración de Macrófagos/metabolismo , Adulto , Anciano , Animales , Hipoxia de la Célula/fisiología , Proliferación Celular , Células Cultivadas , Femenino , Humanos , Hipoxia/sangre , Masculino , Ratones , Persona de Mediana Edad , OximetríaRESUMEN
Chronic kidney disease (CKD) carries an increased risk of cardiovascular disease (CVD). Macrophage migration inhibiting factor (MIF) is a proinflammatory cytokine implicated in the pathogenesis of sepsis, autoimmune disease, atherogenesis, and plaque instability, and is a known cardiac depressant. This post-hoc, cross-sectional study examined whether MIF serum concentrations are elevated in CKD patients. Our study included CKD 3-5 patients with moderate to severe renal dysfunction (n = 257) (mean age SD; 55 +/- 12 years) and 53 controls (60 +/- 12 years). Serum MIF concentrations, measured by enzyme-linked immunosorbent assay (ELISA), were studied in relation to glomerular filtration rate (GFR), presence of CVD, outcome and inflammatory and oxidative stress markers. MIF was significantly elevated in CKD patients compared with controls (CKD: median 676 [range 118-8275 pg/mL] controls: 433 [142-4707] pg/mL; P = 0.008). MIF was also associated with 8-hydroxy-2-deoxyguanosine (8-OH-dG) levels (rho = 0.26; P = 0.001), a marker of oxidative stress, and ICAM-1 levels (rho = 0.14; P = 0.02), a marker of endothelial activation. However, the elevated MIF concentrations were neither correlated with glomerular filtration rate (GFR) nor inflammatory markers such as CRP, IL-6, and TNF. When combining MIF and IL-6 as a marker of inflammation, a significant increase in risk for CVD was found, but when analyzing all-cause mortality, this did not differ significantly with regard to mortality from inflamed patients with low MIF levels. The data suggest that increased serum MIF levels found in CKD is not caused primarily by poor renal function, but is associated with markers of oxidative stress and endothelial activation and may play a role in vascular disease associated with CKD.
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Biomarcadores/sangre , Endotelio/fisiopatología , Factores Inhibidores de la Migración de Macrófagos/sangre , Estrés Oxidativo , Insuficiencia Renal Crónica , Adulto , Anciano , Estudios Transversales , Humanos , Inflamación/sangre , Inflamación/fisiopatología , Masculino , Persona de Mediana Edad , Insuficiencia Renal Crónica/sangre , Insuficiencia Renal Crónica/fisiopatologíaRESUMEN
Invasive breast cancer has a high risk of recurrence to incurable disease and needs improved prognostic and therapeutic tools. Our work combines clinical and molecular analyses to show that the transcriptional repressor HBP1 may be a new target for invasive breast cancer. Previous work indicated that HBP1 regulated proliferation and senescence and inhibited Wnt signaling. Two of these functions have been associated with invasive breast cancer. In 76 breast tumors, we identified 10 HBP1 mutations/variants that were associated with fully invasive breast cancer. In a separate analysis, we found that a subset of invasive breast cancer specimens also had reduced HBP1 mRNA levels. These clinical correlations suggested that mutation or reduction of HBP1 occurs in invasive breast cancer and that HBP1 might regulate the proliferation and invasiveness of this breast cancer type. Analysis of the HBP1 mutants showed they were functionally defective for suppressing Wnt signaling. To test the consequences of reduced HBP1 levels, we used RNA interference to knock down HBP1 and observed increased Wnt signaling, tumorigenic proliferation, and invasiveness in cell and animal breast cancer models. Lastly, statistical analysis of a breast cancer patient database linked reduced HBP1 expression to breast cancer recurrence. In considering two-gene criteria for relapse potential, reduced expression of HBP1 and SFRP1, which is another Wnt inhibitor that was recently linked to invasive breast cancer, strikingly correlated with recurrence. Together, these data indicate that HBP1 may be a molecularly and clinically relevant regulator of breast cancer transitions that eventually lead to poor prognosis.
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Neoplasias de la Mama/metabolismo , Regulación Neoplásica de la Expresión Génica , Proteínas del Grupo de Alta Movilidad/biosíntesis , Proteínas del Grupo de Alta Movilidad/genética , Proteínas Represoras/biosíntesis , Proteínas Represoras/genética , Transcripción Genética , Animales , Femenino , Humanos , Ratones , Ratones SCID , Mutación , Células 3T3 NIH , Invasividad Neoplásica , Metástasis de la Neoplasia , Trasplante de Neoplasias , Resultado del TratamientoRESUMEN
BACKGROUND: Suppression of polymorphonuclear leukocyte (PMNL) apoptosis may cause or exaggerate acute lung injury that is associated with the acute respiratory distress syndrome. We hypothesized that transepithelial migration would modulate PMNL apoptosis. METHOD: PMNLs that were freshly purified from normal volunteers were allowed to migrate across transwell membranes alone or coated with monolayers of human lung epithelial cells in response to chemoattractants (interleukin-8, formyl-methionylleucylphenylalanine and leukotriene B(4)). We assessed for migration efficiency, apoptosis, and functional activity of the PMNLs. Changes in the expression of genes modulating PMNL apoptosis were examined with messenger RNA and protein analyses. RESULTS: Transepithelial migration caused a significant decrease in the percentage of apoptotic PMNLs (interleukin-8; from 31% to 16% at 8 hours; P<.01). This apoptotic delay was sustained to at least 20 hours that was associated with prolongation of PMNL functional activity and independent of chemoattractant-type. Gene and protein expression levels of the antiapoptotic proteins Mcl-1 and 14-3-3 zeta were either augmented or preserved by interleukin-8 treatment alone and after transepithelial migration. CONCLUSION: Our data reveal, for the first time, the important role of transepithelial migration in the modulation of PMNL apoptosis and may provide insights into possible novel targets for the regulation of PMNL apoptosis during lung inflammation and injury.
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Apoptosis/fisiología , Quimiotaxis de Leucocito/fisiología , Pulmón/fisiología , Neutrófilos/fisiología , Proteínas Proto-Oncogénicas c-bcl-2 , Proteínas 14-3-3 , Quimiotaxis de Leucocito/efectos de los fármacos , Epitelio/fisiología , Expresión Génica , Humanos , Interleucina-8/farmacología , Proteína 1 de la Secuencia de Leucemia de Células Mieloides , Proteínas de Neoplasias/metabolismo , Neutrófilos/metabolismo , Superóxidos/metabolismo , Factores de Tiempo , Tirosina 3-Monooxigenasa/metabolismoRESUMEN
OBJECTIVE: Although phytochemical curcumin has been shown to possess anti-inflammatory properties, it remains unknown whether this agent has any beneficial effects in sepsis. The purpose of this study was to demonstrate whether curcumin protects septic animals and, if so, whether activation of peroxisome proliferator-activated receptor (PPAR)-gamma, an anti-inflammatory nuclear receptor, plays any role. DESIGN: Prospective, controlled, and randomized animal study. SETTING: A research institute laboratory. SUBJECTS: Male Sprague-Dawley rats. INTERVENTIONS: A bolus injection of 0.2 micromol of curcumin was given intravenously to male adult rats, followed by continuous infusion of curcumin (0.24 micromol/day) for 3 days via a primed 2-mL mini-pump. The rats were then subjected to sepsis by cecal ligation and puncture (CLP). MEASUREMENTS AND MAIN RESULTS: Serum levels of liver enzymes (alanine aminotransferase and aspartate aminotransferase), lactate, albumin, and tumor necrosis factor (TNF)-alpha were measured at 20 hrs after CLP (i.e., late stage of sepsis). In addition, a 10-day survival curve was conducted following CLP and cecal excision with or without curcumin treatment. Furthermore, macrophages cell line RAW 264.7 cells were treated with curcumin followed by stimulation with endotoxin. TNF-alpha and PPAR-gamma expression were then measured. The results indicate that intravenous administration of curcumin before the onset of sepsis attenuated tissue injury, reduced mortality, and decreased the expression of TNF-alpha in septic animals. Similar results were also found when curcumin was administered after the onset of sepsis. Moreover, the down-regulated PPAR-gamma in the liver at 20 hrs after CLP was significantly improved by curcumin treatment. Concurrent administration of curcumin and GW9662, a specific PPAR-gamma antagonist, completely abolished the beneficial effects of curcumin under such conditions. In cultured RAW 264.7 cells, curcumin inhibited endotoxin-induced increases in TNF-alpha expression and markedly up-regulated PPAR-gamma expression without affecting cell viability. Curcumin also prevented morphologic alterations in macrophages induced by endotoxin. CONCLUSIONS: The protective effect of curcumin makes it or its analogues strong candidates as a novel therapy for sepsis. The beneficial effect of curcumin appears to be mediated by up-regulation of nuclear receptor PPAR-gamma.
Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Curcumina/uso terapéutico , PPAR gamma/fisiología , Sepsis/tratamiento farmacológico , Anilidas/farmacología , Animales , Antiinflamatorios no Esteroideos/administración & dosificación , Línea Celular , Supervivencia Celular/efectos de los fármacos , Curcumina/administración & dosificación , Regulación hacia Abajo , Endotoxinas/farmacología , Lactatos/sangre , Hígado/metabolismo , Macrófagos/efectos de los fármacos , Masculino , PPAR gamma/antagonistas & inhibidores , PPAR gamma/metabolismo , Estudios Prospectivos , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Albúmina Sérica/análisis , Transaminasas/sangre , Factor de Necrosis Tumoral alfa/metabolismo , Regulación hacia ArribaRESUMEN
Delayed polymorphonuclear leukocyte (PMN) apoptosis exacerbates acute lung injury. To reach the alveolar spaces, PMNs must migrate across both pulmonary endothelial and epithelial cell layers. We hypothesized that transmigration across the endothelium-epithelium bilayer suppresses PMN apoptosis and sought to elucidate the underlying mechanisms. PMNs freshly isolated from normal volunteers were allowed to migrate across polycarbonate membranes alone or membranes coated with a bilayer of human lung endothelial and epithelial cells. After migration toward different chemoattractants (IL-8, formyl-Met-Leu-Phe, or leukotriene B(4)), PMN apoptosis and caspase activities were assessed by annexin V, histology, and enzymatic assays, respectively. Messenger RNA and specific protein expression in three receptor ligand-mediated, apoptosis-inducing pathways (Fas, TNF-alpha, and TNF-related apoptosis-inducing ligand) were further examined by gene array, RT-PCR, flow cytometry, and Western blot analyses. The data demonstrated that transbilayer migration suppressed PMN apoptosis, and this effect was not chemoattractant type specific. Kinetic analyses further showed that the delay of apoptosis was sustained to at least 18 h. Transbilayer migration caused significant decreases in caspase (-3, -8, and -9) activities. The changes in apoptosis-related gene expression support the survival role of transbilayer migration. Furthermore, the reduced apoptosis was correlated with downregulation of Fas ligand and TNF receptor 1 expression. Our data reveal that migration across a lung endothelium-epithelium bilayer suppresses PMN apoptosis. The decreased activity and/or expression of proapoptotic proteins may provide possible targets for the regulation of inappropriate delay in PMN apoptosis during lung inflammation and injury.
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Apoptosis/fisiología , Endotelio Vascular , Pulmón , Neutrófilos/fisiología , Anticuerpos Monoclonales/farmacología , Apoptosis/efectos de los fármacos , Caspasas/metabolismo , Movimiento Celular/fisiología , Supervivencia Celular/fisiología , Regulación hacia Abajo/fisiología , Epitelio , Proteína Ligando Fas , Expresión Génica/fisiología , Humanos , Glicoproteínas de Membrana/metabolismo , Neutrófilos/metabolismo , Receptores Tipo I de Factores de Necrosis Tumoral/metabolismo , Factores de Tiempo , Factor de Necrosis Tumoral alfa/farmacología , Receptor fas/inmunologíaRESUMEN
OBJECTIVE: Despite advances in the management of sepsis and acute respiratory distress syndrome, the mortality rate remains high. Delayed apoptosis of neutrophils is associated with multiple organ failure under those conditions. Thus, development of nontoxic neutrophil apoptosis regulating molecules may provide a novel therapeutic strategy. Curcumin is a promising dietary supplement for cancer prevention. However, the effect of curcumin on human neutrophil apoptosis remains unknown. We therefore hypothesized that curcumin would produce a proapoptotic effect on neutrophils. DESIGN: Prospective, controlled, and randomized in vitro study. SETTING: Research institute laboratory. SUBJECTS: Human peripheral neutrophils obtained from normal subjects. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: In the presence or absence of curcumin, both spontaneous neutrophil apoptosis and apoptosis of neutrophils following transmigration across a human lung endothelium-epithelium bilayer were studied by morphology and terminal dUTP nucleotide end labeling analyses, respectively. Myeloperoxidase activity and migration assays were performed to determine the impact of curcumin on neutrophil function. To elucidate the potential mechanism, the p38 mitogen-activated protein kinase pathway and caspase-3 activity were examined by Western blotting and enzymatic analyses. The data demonstrate that curcumin increased constitutive neutrophil apoptosis and abrogated the transbilayer migration-induced delay in neutrophil apoptosis. Neutrophil activation was reduced by curcumin treatment as evidenced by a decrease in migration and myeloperoxidase release. A marked increase in p38 phosphorylation and caspase-3 activity was observed following curcumin exposure. In addition, inhibition of p38 mitogen-activated protein kinase with SB203580 suppressed apoptosis and caspase-3 activation induced by curcumin. Thus, activation of p38 mitogen-activated protein kinase or an increase in caspase-3 activity appears to contribute to the proapoptotic effect of human neutrophil apoptosis by curcumin. CONCLUSION: The characteristics of curcumin, including its proapoptotic effect and antidegranulation effect, make it a potential candidate for the therapy of neutrophil-induced lung injury and sepsis.
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Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Curcumina/farmacología , Neutrófilos/efectos de los fármacos , Proteínas Quinasas p38 Activadas por Mitógenos/efectos de los fármacos , Antineoplásicos/uso terapéutico , Curcumina/uso terapéutico , Humanos , Etiquetado Corte-Fin in Situ , Técnicas In Vitro , Neutrófilos/enzimología , Sepsis/tratamiento farmacológico , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismoRESUMEN
High mobility group box 1 (HMGB1) protein, a late mediator of lethality in sepsis, can induce acute inflammatory lung injury. Here, we identify the critical role of alpha-chemokine receptors in the HMGB1-induced inflammatory injury and show that alpha-chemokine receptor inhibition increases survival in sepsis, in a clinically relevant time frame. Intratracheal instillation of recombinant HMGB1 induces a neutrophilic leukocytosis, preceded by alveolar accumulation of the alpha-chemokine macrophage inflammatory protein-2 and accompanied by injury and increased inflammatory potential within the air spaces. To investigate the role of alpha-chemokine receptors in the injury, we instilled recombinant HMGB1 (0.5 microg) directly into the lungs and administered a subcutaneous alpha-chemokine receptor inhibitor, Antileukinate (200 microg). alpha-Chemokine receptor blockade reduced HMGB1-induced inflammatory injury (neutrophils: 2.9 +/- 3.2 vs. 8.1 +/- 2.4 x 10(4) cells; total protein: 120 +/- 48 vs. 311 +/- 129 microg/ml; reactive nitrogen species: 2.3 +/- 0.3 vs. 3.5 +/- 1.3 microM; and macrophage migration inhibitory factor: 6.4 +/- 4.2 vs. 37.4 +/- 15.9 ng/ml) within the bronchoalveolar lavage fluid, indicating that HMGB1-induced inflammation and injury are alpha-chemokine mediated. Because HMGB1 can mediate late septic lethality, we administered Antileukinate to septic mice and observed increased survival (from 58% in controls to 89%) even when the inhibitor treatment was initiated 24 h after the induction of sepsis. These data demonstrate that alpha-chemokine receptor inhibition can reduce HMGB1-induced lung injury and lethality in established sepsis and may provide a novel treatment in this devastating disease.
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Proteína HMGB1 , Oligopéptidos/farmacología , Neumonía/tratamiento farmacológico , Receptores de Quimiocina/antagonistas & inhibidores , Sepsis/tratamiento farmacológico , Animales , Quimiocina CXCL2 , Quimiocinas/metabolismo , Quimiocinas CXC/metabolismo , Femenino , Proteína HMGB1/farmacocinética , Ratones , Ratones Endogámicos BALB C , Neutrófilos/inmunología , Neumonía/inducido químicamente , Neumonía/inmunología , Neumonía/mortalidad , Alveolos Pulmonares/efectos de los fármacos , Alveolos Pulmonares/inmunología , Alveolos Pulmonares/metabolismo , Receptores de Quimiocina/metabolismo , Síndrome de Dificultad Respiratoria/inducido químicamente , Síndrome de Dificultad Respiratoria/tratamiento farmacológico , Síndrome de Dificultad Respiratoria/inmunología , Síndrome de Dificultad Respiratoria/mortalidad , Sepsis/inmunología , Sepsis/mortalidadRESUMEN
The basic helix-loop-helix (bHLH) proteins are intimately associated with developmental events such as cell differentiation and lineage commitment. The HLH domain in the bHLH motif is responsible for dimerization, whereas the basic region mediates DNA binding. Based on sequence alignment and domain analysis, differentially expressed in chondrocytes/stimulated with retinoic acid/split and hairy-related proteins (DEC/STRA/SHARPs) represent a new class of bHLH proteins. The present study describes the functional characterization of DEC1. Subtractive experiments and blotting analyses demonstrated that DEC1 was highly expressed in colon carcinomas, but not in the adjacent normal tissues. Several cell cycle blockers markedly induced DEC1 expression. Stable transfectants with a tetracycline-inducible construct demonstrated that DEC1 caused proliferation inhibition, antagonized serum deprivation-induced apoptosis and selectively inhibited the activation of procaspases. These activities were highly correlated with the abundance of tetracycline-induced DEC1. Stable transfectants expressing a mutant DEC1 (lacking the DNA-binding domain) exhibited neither proliferation inhibition nor apoptotic antagonism, which suggests that DNA binding is required for these actions. Enzymic assays and immunoblotting analyses demonstrated that induction of DEC1 by tetracycline significantly decreased the activation of procaspases 3, 7 and 9 but not procaspase 8. The selective suppression on the activation of procaspases 3, 7 and 9 over procaspase 8 suggests that DEC1-mediated anti-apoptosis is achieved by blocking apoptotic pathways initiated via the mitochondria. The results functionally distinguish DEC1 from other bHLH proteins and directly link this factor to oncogenesis.
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Adenocarcinoma/genética , Caspasas/metabolismo , Neoplasias del Colon/genética , Precursores Enzimáticos/metabolismo , Proteínas de Homeodominio/genética , Adenocarcinoma/patología , Adulto , Secuencia de Aminoácidos , Apoptosis/efectos de los fármacos , Apoptosis/fisiología , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico , Caspasa 3 , Caspasa 7 , Caspasa 8 , Caspasa 9 , Caspasas/efectos de los fármacos , Caspasas/genética , Ciclo Celular/efectos de los fármacos , División Celular/genética , Neoplasias del Colon/patología , Medio de Cultivo Libre de Suero/farmacología , Activación Enzimática/efectos de los fármacos , Precursores Enzimáticos/efectos de los fármacos , Precursores Enzimáticos/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Secuencias Hélice-Asa-Hélice , Proteínas de Homeodominio/metabolismo , Humanos , Hidroxiurea/farmacología , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , MutaciónRESUMEN
Inhaled nitric oxide (iNO) is used clinically to treat pulmonary hypertension in newborns, often in conjunction with hyperoxia (NO/O2). Prolonged exposure to NO/O2 causes synergistic lung injury and death of lung epithelial cells. To explore the mechanisms involved, oxygen-resistant HeLa-80 cells were exposed to NO +/- O2. Exposure to NO and O2 induced a synergistic cytotoxicity, accompanied with apoptotic characteristics, including elevated caspase-3-like activity, Annexin V incorporation, and nuclear condensation. This apoptosis was associated with a synergistic suppression of NF-kappaB activity. Cells lacking functional NF-kappaB p65 subunit were more sensitive to NO/O2 than their wild type counterparts. This injury was partially rescued by transfection with a p65 expression construct, suggesting an inverse relationship between NF-kappaB and susceptibility to the cytotoxicity of NO/O2. Despite the reduced NF-kappaB activity in cells exposed to NO +/- O2, IkappaBalpha was degraded, suggesting that pathways regulating the steady-state levels of IkappaB were not involved. However, exposure to NO/O2 caused a marked reduction in nuclear localization and an increase in protein carbonyl formation of NF-kappaB p65 subunit. These results suggest that NO/O2-induced apoptosis occurs by suppressing NF-kappaB activity.