Subject(s)
Antineoplastic Agents , Leukemia, Myeloid, Acute , Humans , Adult , Salvage Therapy , Antineoplastic Agents/therapeutic use , Leukemia, Myeloid, Acute/drug therapy , Leukemia, Myeloid, Acute/genetics , Bridged Bicyclo Compounds, Heterocyclic/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic useABSTRACT
OBJECTIVE: Suboptimal diabetic eye disease screening is a major cause of preventable vision loss. Screening barriers include mydriasis and the need for dedicated screening appointments. The Clearsight trial assessed whether nonmydriatic ultra-widefield (NM UWF) screening on the day of a diabetes clinic visit improved detection of clinically important eye disease versus usual screening. RESEARCH DESIGN AND METHODS: This single-center, randomized, parallel-group controlled trial was conducted at St. Joseph's Health Care, London, Ontario, Canada. Adults with diabetes due for screening were randomized to same-day, on-site screening (NM UWF imaging) on the day of a scheduled diabetes clinic visit or usual screening (encouraged to arrange optometrist screening). The primary outcome was detection of actionable eye disease (AED), defined as the need for an ophthalmology referral or increased ocular surveillance. The primary analysis (modified intention-to-screen) compared the proportions of AED between groups within 1 year of enrollment. RESULTS: Of 740 participants randomized between 7 March 2016 and 17 April 2019, 335 on-site screening and 323 usual screening participants met criteria for the primary analysis. More AED was detected in the on-site screening group than in the usual screening group (50 of 335 [14.9%] vs. 22 of 323 [6.8%]; adjusted odds ratio 2.51; 95% CI 1.49-4.36). The number needed to screen by on-site screening in order to detect 1 additional patient with AED was 13 (95% CI 8-29). CONCLUSIONS: Same-day, on-site screening by NM UWF imaging increased the detection of clinically important diabetic eye disease versus usual screening. Integration of NM UWF imaging into routine diabetes clinic visits improved screening adherence and has the potential to prevent vision loss.
Subject(s)
Diabetes Mellitus , Diabetic Retinopathy , Adult , Humans , Diabetic Retinopathy/diagnostic imaging , Retina , Mass Screening , OntarioABSTRACT
Acute myeloid leukemia (AML) is a cancer of myeloid-lineage cells with limited therapeutic options. We previously combined ex vivo drug sensitivity with genomic, transcriptomic, and clinical annotations for a large cohort of AML patients, which facilitated discovery of functional genomic correlates. Here, we present a dataset that has been harmonized with our initial report to yield a cumulative cohort of 805 patients (942 specimens). We show strong cross-cohort concordance and identify features of drug response. Further, deconvoluting transcriptomic data shows that drug sensitivity is governed broadly by AML cell differentiation state, sometimes conditionally affecting other correlates of response. Finally, modeling of clinical outcome reveals a single gene, PEAR1, to be among the strongest predictors of patient survival, especially for young patients. Collectively, this report expands a large functional genomic resource, offers avenues for mechanistic exploration and drug development, and reveals tools for predicting outcome in AML.
Subject(s)
Leukemia, Myeloid, Acute , Cell Differentiation , Cohort Studies , Humans , Leukemia, Myeloid, Acute/drug therapy , Leukemia, Myeloid, Acute/genetics , Receptors, Cell Surface/genetics , TranscriptomeABSTRACT
BACKGROUND: While studies have reported factors affecting adherence to diabetic care plans from a chronic disease perspective, no studies have addressed issues with post-discharge adherence facing patients with diabetes after an emergency department (ED) presentation for hyperglycaemia. This study's objectives were to describe patient perspectives on their experience during and after an ED visit for hyperglycaemia and to identify factors that influence postdischarge adherence. METHODS: We conducted a qualitative description (QD) study of adult patients who had visited a Canadian ED for hyperglycaemia. Consistent with QD, purposive sampling was utilised, seeking diversity across age, gender and diabetes type. Participants took part in semistructured interviews and thematic analysis was used to identify and describe core themes. Frequent team meetings were held to review the analysis and to develop the final list of themes used to recode the data set. Analytic insights were tracked using reflective memos and an audit trail documented all steps and decisions. RESULTS: 22 patients with type 1 and 2 diabetes were interviewed from June to October 2019. Participants identified several factors that impacted their ability to adhere to discharge plans: communication of instructions, psychosocial factors (financial considerations, shame and guilt, stigma and mental health), access to follow-up care and paediatric to adult care transitions. CONCLUSIONS: This study describes the patient experience with the communication of discharge instructions, as well as factors affecting adherence post-ED discharge for hyperglycaemia. Our findings suggest four strategies that could improve the patient experience, improve adherence to discharge plans and potentially decrease the frequency of recurrent ED visits for hyperglycaemia.
Subject(s)
Diabetes Mellitus, Type 1 , Diabetes Mellitus, Type 2 , Hyperglycemia , Transition to Adult Care , Adult , Aftercare , Canada , Child , Communication , Emergency Service, Hospital , Humans , Hyperglycemia/therapy , Patient DischargeABSTRACT
BACKGROUND: Patients with diabetes and chronic kidney disease (CKD) have complex diabetes care needs. Diabetes educators can play an important role in their clinical care. AIM: To understand diabetes educators' experience providing diabetes support to patients with CKD and elicit their view on the additional care needs of this population. METHODS: We conducted a quantitative online survey of diabetes educators between May 2019 and May 2020. We surveyed English-speaking educators actively practicing in Ontario, Canada for at least 1 year. We recruited them through provincial Diabetes Education Programs and Diabetes Education Section Chairs of Diabetes Canada. RESULTS: We made email contact with 219/233 (94%) Diabetes Education Programs and 11/12 (92%) provincial Diabetes Canada Section Chairs. 122 unique diabetes educators submitted complete surveys (survey participation rate â¼79%). Most worked in community education programs (91%). Almost half were registered nurses (48%), and 39% had practiced for more than 15 years. Respondents noted difficulty helping patients balance complex medical conditions (19%), faced socioeconomic barriers (17%), and struggled to provide dietary advice (16%). One-third were uncertain of how to support those receiving dialysis. Eighty-five percent felt they needed more training and education to care for this high-risk group. When asked about the care needs of patients with CKD, almost all (90%) felt that patients needed more diabetes support in general. Improvement in care coordination was most commonly suggested (38%). CONCLUSIONS: In this study of the diabetes educators' experience treating patients with diabetes and CKD, respondents noted numerous challenges. There may be opportunities to better support both diabetes care professionals, and patients who live with multiple medical comorbidities.
ABSTRACT
BACKGROUND: People with diabetes mellitus commonly experience hypoglycemia, but they may not necessarily present to hospital after severe hypoglycemia requiring paramedic assistance. We sought to describe the incidence and characteristics of calls for hypoglycemia requiring paramedic assistance among adults in southwestern Ontario, Canada, and to determine predictors of hospital transport. METHODS: This population-based retrospective cohort study used data extracted from ambulance call reports (ACRs) of 8 paramedic services of the Southwest Ontario Regional Base Hospital Program from January 2008 to June 2014. We described calls in which treatment for hypoglycemia was administered, summarized the incidence of hypoglycemia calls and performed logistic regression to determine predictors of hospital transport. RESULTS: Out of 470 467 ACRs during the study period, 9185 paramedic calls occurred in which hypoglycemia treatment was administered to an adult (mean age 60.2 yr, 56.8% male, 81.1% with documented diabetes). Refusal of hospital transport occurred in 2243 (24.4%) of calls. Documented diabetes diagnosis (adjusted odds ratio [OR] 0.82, 95% confidence interval [CI] 0.69-0.96), higher capillary blood glucose (adjusted OR 0.31, 95% CI 0.22-0.44) and overnight calls (adjusted OR 0.80, 95% CI 0.72-0.91) were associated with lower odds of hospital transport. Higher-acuity calls (adjusted OR 2.05, 95% CI 1.58-2.66) were associated with higher odds of transport. The estimated annual incidence rate of hypoglycemia requiring paramedic assistance was 108 per 10 000 people with diabetes per year. INTERPRETATION: Hypoglycemia requiring paramedic assistance in southwestern Ontario is common, and close to 25% of calls do not result in hospital transport. Physicians managing diabetes care may be unaware of patients' hypoglycemia requiring paramedic care, suggesting a potential gap in follow-up care; we suggest that paramedics play an important role in identifying those at high recurrence risk and communicating with their care providers.
Subject(s)
Diabetes Mellitus/epidemiology , Emergency Medical Services/methods , Emergency Medical Technicians , Glucagon/administration & dosage , Glucose/administration & dosage , Hypoglycemia/drug therapy , Hypoglycemia/epidemiology , Sweetening Agents/administration & dosage , Adult , Aged , Ambulances , Comorbidity , Female , Humans , Incidence , Logistic Models , Male , Middle Aged , Ontario/epidemiology , Retrospective Studies , Treatment OutcomeABSTRACT
AIMS: Hypoglycaemia is a common treatment consequence in diabetes mellitus. Prior studies have shown that a large proportion of people with paramedic assist-requiring hypoglycaemia prefer not to be transported to hospital. Thus, these episodes are "invisible" to their usual diabetes care providers. A direct electronic referral programme where paramedics sent referrals focused hypoglycaemia education at the time of paramedic assessment was implemented in our region for 18 months; however, referral programme uptake was low. In this study, we examined patient and paramedic experiences with a direct electronic referral programme for hypoglycaemia education postparamedic assist-requiring hypoglycaemia, including barriers to programme referral and education attendance. METHODS: We surveyed paramedics and conducted semistructured telephone interviews of patients with paramedic-assisted hypoglycaemia who consented to the referral programme and were scheduled for an education session in London and Middlesex County, Canada. RESULTS: Paramedics and patient participants felt that the direct referral programme was beneficial. A third of paramedics who responded to our survey used the referral programme for each encounter where they treated patients for hypoglycaemia. Patients felt very positive about the referral programme and their paramedic encounter; however, they described embarrassment, guilt and prior negative experience as key barriers to attending education. CONCLUSIONS: Paramedics and patients felt that direct referral for focused hypoglycaemia education postparamedic assist-requiring hypoglycaemia was an excellent strategy. Despite this, referral programme participation was low and thus there remain ongoing barriers to implementation and attendance. Future iterations should consider how best to meet patient needs through innovative delivery methods.
Subject(s)
Allied Health Personnel/education , Electronics , Emergency Medical Technicians/education , Hypoglycemia/therapy , Patient Education as Topic/methods , Qualitative Research , Referral and Consultation/organization & administration , Aged , Female , Follow-Up Studies , Humans , Male , Middle Aged , Ontario , Retrospective Studies , Surveys and QuestionnairesSubject(s)
Diabetes Mellitus, Type 1 , Diabetes Mellitus, Type 2 , Diabetic Retinopathy , Adult , Diabetes Mellitus, Type 1/complications , Diabetes Mellitus, Type 1/epidemiology , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/epidemiology , Diabetic Retinopathy/diagnosis , Diabetic Retinopathy/epidemiology , Fibric Acids , Humans , Prevalence , Risk FactorsABSTRACT
Health care systems often provide a range of options of care for patients with illnesses who do not require hospital admission. For individuals with diabetes, these options may include primary care providers, specialized diabetes clinics, and urgent care and walk-in clinics. We explored the reasons why patients choose the Emergency Department over other health care settings when seeking care for hyperglycemia.
ABSTRACT
OBJECTIVES: Few studies have examined the effect of specialized care on patients with diabetes who present to the emergency department (ED) visits for acute hyperglycemia. The objective of this study was to characterize ED patients presenting with hyperglycemia and compare the 30-day outcomes of those followed by specialized diabetes clinics with those not followed. We hypothesized that patients followed by specialized clinics would have improved clinical outcomes compared with those who had no specialized follow up. METHODS: We conducted this single-centre retrospective cohort study of adults (≥18 years) with an ED visit for hyperglycemia over 1 year (January to December 2014). Data from ED visits were linked to specialized diabetes clinic records, which contained diabetes-specific clinical data not available in ED visit records. Descriptive statistics were summarized and comparisons between groups were performed, when appropriate. RESULTS: There were 456 patients (55.0% men; mean age, 47.7 years; 46.3% with type 1 diabetes) with 250 followed by the specialized diabetes clinics. The 206 patients who were not followed by the diabetes clinics (45%) were more likely to have a recurrent hyperglycemia ED visit (32.5% vs 9.6%, p<0.001) and to require hospitalization for hyperglycemia (14.1% vs 5.2%, p=0.001) within 30 days of initial presentation. CONCLUSIONS: Patients followed by specialized diabetes clinics had fewer recurrent ED visits and hospital admissions for hyperglycemia at 30 days compared with those not followed, suggesting that greater continuity of care between endocrinology and emergency medicine may help reduce these adverse outcomes for patients with diabetes.
Subject(s)
Biomarkers/analysis , Diabetes Mellitus, Type 1/physiopathology , Diabetes Mellitus, Type 2/physiopathology , Emergency Service, Hospital/statistics & numerical data , Hospitalization/statistics & numerical data , Hyperglycemia/prevention & control , Specialization/standards , Ambulatory Care , Blood Glucose/analysis , Canada/epidemiology , Delivery of Health Care , Diabetes Mellitus, Type 1/drug therapy , Diabetes Mellitus, Type 2/drug therapy , Female , Follow-Up Studies , Humans , Hyperglycemia/epidemiology , Hyperglycemia/pathology , Male , Middle Aged , Prognosis , Retrospective StudiesABSTRACT
A 21-year-old male with known type 1 diabetes mellitus presented to the emergency department (ED) with two days of vomiting, polyuria, and polydipsia after several days of viral upper respiratory tract infection symptoms. Since his symptom onset, his home capillary blood glucose readings have been higher than usual. On the day of presentation, his glucometer read "high," and he could not tolerate oral fluids. On examination, his pulse was 110 beats/minute, and his respiratory rate was 24 breaths/minute. He was afebrile, and the remaining vital signs were normal. Other than dry mucous membranes, his cardiopulmonary, abdominal, and neurologic exams were unremarkable. Venous blood gas demonstrated a pH of 7.25 mm Hg, pCO2 of 31 mm Hg, HCO3 of 13 mm Hg, anion gap of 18 mmol/L, and laboratory blood glucose of 40 mmol/L, as well as serum ketones measuring "large."
Subject(s)
Diabetes Mellitus, Type 1 , Diabetic Ketoacidosis , Diabetes Mellitus, Type 1/complications , Emergency Service, Hospital , Humans , Male , Young AdultSubject(s)
Diabetes Mellitus, Type 1/epidemiology , Diabetes Mellitus, Type 2/epidemiology , Diabetes, Gestational/epidemiology , Pregnancy in Diabetics/epidemiology , Adult , Ambulatory Care Facilities , Body Weight , Female , Humans , Ontario/epidemiology , Pregnancy , Pregnancy Outcome , Risk FactorsABSTRACT
The implementation of targeted therapies for acute myeloid leukaemia (AML) has been challenging because of the complex mutational patterns within and across patients as well as a dearth of pharmacologic agents for most mutational events. Here we report initial findings from the Beat AML programme on a cohort of 672 tumour specimens collected from 562 patients. We assessed these specimens using whole-exome sequencing, RNA sequencing and analyses of ex vivo drug sensitivity. Our data reveal mutational events that have not previously been detected in AML. We show that the response to drugs is associated with mutational status, including instances of drug sensitivity that are specific to combinatorial mutational events. Integration with RNA sequencing also revealed gene expression signatures, which predict a role for specific gene networks in the drug response. Collectively, we have generated a dataset-accessible through the Beat AML data viewer (Vizome)-that can be leveraged to address clinical, genomic, transcriptomic and functional analyses of the biology of AML.
Subject(s)
Gene Expression Regulation, Neoplastic/genetics , Genome, Human/genetics , Genomics , Leukemia, Myeloid, Acute/genetics , Core Binding Factor Alpha 2 Subunit/genetics , DNA (Cytosine-5-)-Methyltransferases/genetics , DNA Methyltransferase 3A , Datasets as Topic , Exome/genetics , Female , Humans , Leukemia, Myeloid, Acute/drug therapy , Leukemia, Myeloid, Acute/metabolism , Male , Molecular Targeted Therapy , Nuclear Proteins/genetics , Nucleophosmin , Proto-Oncogene Proteins/genetics , Repressor Proteins/genetics , Sequence Analysis, RNA , Serine-Arginine Splicing Factors/geneticsABSTRACT
In many malignancies, the tumor microenvironment includes CSF1R-expressing supportive monocyte/macrophages that promote tumor cell survival. For chronic lymphocytic leukemia (CLL), these supportive monocyte/macrophages are known as nurse-like cells (NLCs), although the potential effectiveness of selective small-molecule inhibitors of CSF1R against CLL is understudied. Here, we demonstrate the preclinical activity of two inhibitors of CSF1R, GW-2580 and ARRY-382, in primary CLL patient samples. We observed at least 25% of CLL samples showed sub-micromolar sensitivity to CSF1R inhibitors. This sensitivity was observed in samples with varying genetic and clinical backgrounds, although higher white cell count and monocyte cell percentage was associated with increased sensitivity. Depleting CD14-expressing monocytes preferentially decreased viability in samples sensitive to CSF1R inhibitors, and treating samples with CSF1R inhibitors eliminated the presence of NLCs in long-term culture conditions. These results indicate that CSF1R small-molecule inhibitors target CD14-expressing monocytes in the CLL microenvironment, thereby depriving leukemia cells of extrinsic support signals. In addition, significant synergy was observed combining CSF1R inhibitors with idelalisib or ibrutinib, two current CLL therapies that disrupt tumor cell intrinsic B-cell receptor signaling. These findings support the concept of simultaneously targeting supportive NLCs and CLL cells and demonstrate the potential clinical utility of this combination.
ABSTRACT
INTRODUCTION: Suboptimal screening for diabetic eye disease is a major cause of preventable vision loss. Screening barriers include mydriasis and the extra time patients need to attend dedicated eye screening appointments. In the Clearsight trial, we are testing whether screening by non-mydriatic ultra-wide field (NM UWF) imaging on the day patients attend their diabetes outpatient clinic visit improves detection of clinically important eye disease compared with usual screening. METHODS AND ANALYSIS: Patients with diabetes due for a screening eye exam by the 2013 Canadian Diabetes Association (CDA) practice guidelines are being randomised to on-site screening by NM UWF imaging on the day of their clinic visit or to usual screening where, per CDA guidelines, they are encouraged to arrange an exam by an optometrist. The primary outcome is actionable eye disease (AED) based on a need for referral to ophthalmology and/or increased ocular surveillance. The primary analysis will use an intention-to-screen approach that compares the proportions of detected AED between on-site and usual screening groups under a superiority hypothesis in favour of on-site screening. With 740 randomised participants, the study will have 80% power to detect ≥5% absolute increase in the AED rate among on-site screening versus usual screening participants. This difference translates into a number-needed-to-screen by on-site screening of 20 to detect 1 additional person with AED. ETHICS AND DISSEMINATION: The protocol was approved by the institutional review board of Western University. The findings of the trial will be disseminated directly to participants and through peer-reviewed publications and conference presentations. TRIAL REGISTRATION NUMBER: ClinicalTrials.Gov NCT02579837 (registered 16 October 2015). PROTOCOL ISSUE DATE: 18 November 2015.
Subject(s)
Diabetes Mellitus , Diabetic Retinopathy/diagnosis , Mass Screening , Retina/pathology , Adolescent , Adult , Aged , Diabetic Retinopathy/diagnostic imaging , Female , Humans , Male , Middle Aged , Mydriatics , Research DesignABSTRACT
PURPOSE: Despite significant therapeutic progress in multiple myeloma, drug resistance is uniformly inevitable and new treatments are needed. Our aim was to identify novel, efficacious small-molecule combinations for use in drug resistant multiple myeloma. EXPERIMENTAL DESIGN: A panel of 116 small molecule inhibitors was used to screen resistant myeloma cell lines for potential therapeutic targets. Agents found to have enhanced activity in the bortezomib or melphalan resistant myeloma cell lines were investigated further in combination. Synergistic combinations of interest were evaluated in primary patient cells. RESULTS: The overall single-agent drug sensitivity profiles were dramatically different between melphalan and bortezomib resistant cells, however, the bromodomain inhibitor, CPI203, was observed to have enhanced activity in both the bortezomib and melphalan resistant lines compared to their wild-type counterparts. The combination of bortezomib and CPI203 was found to be synergistic in both the bortezomib and melphalan resistant cell lines as well as in a primary multiple myeloma sample from a patient refractory to recent proteasome inhibitor treatment. The CPI203-bortezomib combination led to enhanced apoptosis and anti-proliferative effects. Finally, in contrast to prior reports of synergy between bortezomib and other epigenetic modifying agents, which implicated MYC downregulation or NOXA induction, our analyses suggest that CPI203-bortezomib synergy is independent of these events. CONCLUSION: Our preclinical data supports a role for the clinical investigation of the bromodomain inhibitor CPI203 combined with bortezomib or alkylating agents in resistant multiple myeloma.
Subject(s)
Acetamides/pharmacology , Antineoplastic Combined Chemotherapy Protocols/pharmacology , Azepines/pharmacology , Bortezomib/pharmacology , Multiple Myeloma/drug therapy , Small Molecule Libraries/pharmacology , Acetamides/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Apoptosis/drug effects , Azepines/administration & dosage , Bortezomib/administration & dosage , Cell Line, Tumor , Cell Proliferation/drug effects , Drug Resistance, Neoplasm , Drug Synergism , Humans , Multiple Myeloma/pathologyABSTRACT
A method is described for measuring the effective electronic conductivity of porous fuel cell catalyst layers (CLs) as a function of relative humidity (RH). Four formulations of CLs with different carbon black (CB) contents and ionomer equivalent weights (EWs) were tested. The van der Pauw method was used to measure the sheet resistance (RS), which increased with RH for all samples. The increase was attributed to ionomer swelling upon water uptake, which affects the connectivity of CB aggregates. Greater increases in RS were observed for samples with lower EW, which uptake more water on a mass basis per mass ionomer. Transient RS measurements were taken during absorption and desorption, and the resistance kinetics were fit using a double exponential decay model. No hysteresis was observed, and the absorption and desorption kinetics were virtually symmetric. Thickness measurements were attempted at different RHs, but no discernible changes were observed. This finding led to the conclusion that the conducting Pt/C volume fraction does not change with RH, which suggests that effective medium theory models that depend on volume fraction alone cannot explain the reduction in conductivity with RH. The merits of percolation-based models were discussed. Optical micrographs revealed an extensive network of "mud cracks" in some samples. The influence of water sorption on CL conductivity is primarily explained by ionomer swelling, and its effects on the quantity and quality of interaggregate contacts were discussed.
ABSTRACT
The olfactory bulb contains the first synaptic relay in the olfactory pathway, the sensory system in which odorants are detected enabling these chemical stimuli to be transformed into electrical signals and, ultimately, the perception of odor. Acid-sensing ion channels (ASICs), a family of proton-gated cation channels, are widely expressed in neurons of the central nervous system. However, no direct electrophysiological and pharmacological characterizations of ASICs in olfactory bulb neurons have been described. Using a combination of whole-cell patch-clamp recordings and biochemical and molecular biological analyses, we demonstrated that functional ASICs exist in mouse olfactory bulb mitral/tufted (M/T) neurons and mainly consist of homomeric ASIC1a and heteromeric ASIC1a/2a channels. ASIC activation depolarized cultured M/T neurons and increased their intracellular calcium concentration. Thus, ASIC activation may play an important role in normal olfactory function.
Subject(s)
Acid Sensing Ion Channels/metabolism , Calcium/metabolism , Ion Channel Gating/physiology , Membrane Potentials/physiology , Olfactory Bulb/physiology , Sensory Receptor Cells/physiology , Animals , Calcium Signaling/physiology , Cells, Cultured , Mice , Sensory Receptor Cells/classificationABSTRACT
We report here an isatin derivative 45 (ID45) against coxsackievirus B3 (CVB3) replication, which was synthesized based on a high-throughput screen of a unique natural product library. ID45 showed the most potent anti-CVB3 activity among the four synthesized compounds. Treatment of cells with ID45 before or after infection significantly reduced viral particle formation, resulting in protection of cells from virus-induced apoptosis. In addition, ID45 treatment caused remarkable up-regulation of glucose-regulated protein 78 (GRP78), a hallmark of endoplasmic reticulum (ER) stress and an indicator of enhanced cell viability. In identifying the ER stress response pathway induced by ID45, we found that ID45 activated PKR-like ER protein kinase (PERK) but failed to up-regulate eIF2α phosphorylation. Instead ID45 activated transcription factor Nrf2 (NF-E2-related factor-2), which is evidenced by its nuclear translocation and upregulation of its downstream target genes NQO1 (NAD(P)H quinone-oxidoreductase 1) and GCLM (glutamate-cysteine ligase, modifier subunit). This observation was further verified by using siRNAs of GRP78 or Nrf2, which blocked both the translocation of Nrf2 and up-regulation of its target genes, leading to aggressive viral replication and enhanced cell apoptosis. Finally, we found that ID45-induced up-regulation of NQO1 protected eIF4GI, a eukaryotic cap-dependent translation initiation factor, from cleavage by CVB3 protease and degradation by proteasomes. Taken together, our findings established that a novel antiviral mechanism of isatin derivative ID45 inhibits CVB3 replication by promoting cell survival through a PERK/Nrf2-dependent ER stress pathway, which benefits host cap-dependent translation but suppresses CVB3 cap-independent translation.
Subject(s)
Antiviral Agents/pharmacology , Gene Expression Regulation, Viral/drug effects , Isatin/chemistry , NF-E2-Related Factor 2/metabolism , eIF-2 Kinase/metabolism , Blotting, Western , Cell Survival/drug effects , Dose-Response Relationship, Drug , Endoplasmic Reticulum Chaperone BiP , HeLa Cells , Humans , Isatin/chemical synthesis , Isatin/pharmacology , Models, Biological , NF-E2-Related Factor 2/chemistry , NF-E2-Related Factor 2/genetics , Protein Biosynthesis/drug effects , Virus Replication/drug effects , eIF-2 Kinase/chemistry , eIF-2 Kinase/geneticsABSTRACT
BACKGROUND: There is increasing evidence for rapid nongenomic effects of aldosterone. Therefore, we studied the immediate effects of aldosterone on vascular reactivity in rat aortic ring segments and on endothelial and vascular smooth muscle cellular responses. METHODS AND RESULTS: In endothelium-intact ring segments, aldosterone attenuated phenylephrine-mediated constriction (maximal reduction, 25+/-4% below control phenylephrine-mediated constriction). In contrast, in endothelium-denuded vessels, aldosterone mediated a monophasic dose-dependent enhancement of vasoconstrictor response. In endothelial cells, aldosterone caused a phosphatidylinositol 3-kinase (PI3K)-dependent increase in nitric oxide synthase activity as well as PI3K-dependent activation of extracellular signal-regulated kinase 1/2 and p70 S6 kinase. CONCLUSIONS: Overall, these data support a novel effect of aldosterone on vascular endothelial and smooth muscle cell function. These rapid effects of aldosterone might be important in both the short- and long-term regulation of peripheral vascular resistance. Furthermore, in the setting of endothelial dysfunction, alterations in aldosterone's short-term vascular responses might contribute to its pathophysiological effects in cardiovascular disease.