Different Strategies to Execute Multi-Database Studies for Medicines Surveillance in Real-World Setting: A Reflection on the European Model.

Although postmarketing studies conducted in population-based databases often contain information on patients in the order of millions, they can still be underpowered if outcomes or exposure of interest is rare, or the interest is in subgroup effects. Combining several databases might provide the statistical power needed. A multi-database study (MDS) uses at least two healthcare databases, which are not linked with each other at an individual person level, with analyses carried out in parallel across each database applying a common study protocol. Although many MDSs have been performed in Europe in the past 10 years, there is a lack of clarity on the peculiarities and implications of the existing strategies to conduct them. In this review, we identify four strategies to execute MDSs, classified according to specific choices in the execution: (A) local analyses, where data are extracted and analyzed locally, with programs developed by each site; (B) sharing of raw data, where raw data are locally extracted and transferred without analysis to a central partner, where all the data are pooled and analyzed; (C) use of a common data model with study-specific data, where study-specific data are locally extracted, loaded into a common data model, and processed locally with centrally developed programs; and (D) use of general common data model, where all local data are extracted and loaded into a common data model, prior to and independent of any study protocol, and protocols are incorporated in centrally developed programs that run locally. We illustrate differences between strategies and analyze potential implications.

Regulatory and health technology assessment advice on postlicensing and postlaunch evidence generation is a foundation for lifecycle data collection for medicines.

The understanding of the benefit risk profile, and relative effectiveness of a new medicinal product, are initially established in a circumscribed patient population through clinical trials. There may be uncertainties associated with the new medicinal product that cannot be, or do not need to be resolved before launch. Postlicensing or postlaunch evidence generation (PLEG) is a term for evidence generated after the licensure or launch of a medicinal product to address these remaining uncertainties. PLEG is thus part of the continuum of evidence development for a medicinal product, complementing earlier evidence, facilitating further elucidation of a product's benefit/risk profile, value proposition, and/or exploring broader aspects of disease management and provision of healthcare. PLEG plays a role in regulatory decision making, not only in the European Union but also in other jurisdictions including the USA and Japan. PLEG is also relevant for downstream decision-making by health technology assessment bodies and payers. PLEG comprises studies of different designs, based on data collected in observational or experimental settings. Experience to date in the European Union has indicated a need for improvements in PLEG. Improvements in design and research efficiency of PLEG could be addressed through more systematic pursuance of Scientific Advice on PLEG with single or multiple decision makers. To date, limited information has been available on the rationale, process or timing for seeking PLEG advice from regulators or health technology assessment bodies. This article sets out to address these issues and to encourage further uptake of PLEG advice.

Can We Rely on Results From IQVIA Medical Research Data UK Converted to the Observational Medical Outcome Partnership Common Data Model?: A Validation Study Based on Prescribing Codeine in Children.

Exploring and combining results from more than one real-world data (RWD) source might be necessary in order to explore variability and demonstrate generalizability of the results or for regulatory requirements. However, the heterogeneous nature of RWD poses challenges when working with more than one source, some of which can be solved by analyzing databases converted into a common data model (CDM). The main objective of the study was to evaluate the implementation of the Observational Medical Outcome Partnership (OMOP) CDM on IQVIA Medical Research Data (IMRD)-UK data. A drug utilization study describing the prescribing of codeine for pain in children was used as a case study to be replicated in IMRD-UK and its corresponding OMOP CDM transformation. Differences between IMRD-UK source and OMOP CDM were identified and investigated. In IMRD-UK updated to May 2017, results were similar between source and transformed data with few discrepancies. These were the result of different conventions applied during the transformation regarding the date of birth for children younger than 15 years and the start of the observation period, and of a misclassification of two drug treatments. After the initial analysis and feedback provided, a rerun of the analysis in IMRD-UK updated to September 2018 showed almost identical results for all the measures analyzed. For this study, the conversion to OMOP CDM was adequate. Although some decisions and mapping could be improved, these impacted on the absolute results but not on the study inferences. This validation study supports six recommendations for good practice in transforming to CDMs.

Big Data - How to Realize the Promise.

The increasing volume and complexity of data now being captured across multiple settings and devices offers the opportunity to deliver a better characterization of diseases, treatments, and the performance of medicinal products in individual healthcare systems. Such data sources, commonly labeled as big data, are generally large, accumulating rapidly, and incorporate multiple data types and forms. Determining the acceptability of these data to support regulatory decisions demands an understanding of data provenance and quality in addition to confirming the validity of new approaches and methods for processing and analyzing these data. The Heads of Agencies and the European Medicines Agency Joint Big Data Taskforce was established to consider these issues from the regulatory perspective. This review reflects the thinking from its first phase and describes the big data landscape from a regulatory perspective and the challenges to be addressed in order that regulators can know when and how to have confidence in the evidence generated from big datasets.

Electronic healthcare databases in Europe: descriptive analysis of characteristics and potential for use in medicines regulation.

OBJECTIVE: Electronic healthcare databases (EHDs) are useful tools for drug development and safety evaluation but their heterogeneity of structure, validity and access across Europe complicates the conduct of multidatabase studies. In this paper, we provide insight into available EHDs to support regulatory decisions on medicines. METHODS: EHDs were identified from publicly available information from the European Network of Centres for Pharmacoepidemiology and Pharmacovigilance resources database, textbooks and web-based searches. Databases were selected using criteria related to accessibility, longitudinal dimension, recording of exposure and outcomes, and generalisability. Extracted information was verified with the database owners. RESULTS: A total of 34 EHDs were selected after applying key criteria relevant for regulatory purposes. The most represented regions were Northern, Central and Western Europe. The most frequent types of data source were electronic medical records (44.1%) and record linkage systems (29.4%). The median number of patients registered in the 34 data sources was 5 million (range 0.07-15 million) while the median time covered by a database was 18.5 years. Paediatric patients were included in 32 databases (94%). Completeness of information on drug exposure was variable. Published validation studies were found for only 17 databases (50%). Some level of access exists for 25 databases (73.5%), and 23 databases (67.6%) can be linked through a personal identification number to other databases with parent-child linkage possible in 7 (21%) databases. Eight databases (23.5%) were already transformed or were in the process of being transformed into a common data model that could facilitate multidatabase studies. CONCLUSION: A Few European databases meet minimal regulatory requirements and are readily available to be used in a regulatory context. Accessibility and validity information of the included information needs to be improved. This study confirmed the fragmentation, heterogeneity and lack of transparency existing in many European EHDs.

EU-funded initiatives for real world evidence: descriptive analysis of their characteristics and relevance for regulatory decision-making.

INTRODUCTION: A review of European Union (EU)-funded initiatives linked to 'Real World Evidence' (RWE) was performed to determine whether their outputs could be used for the generation of real-world data able to support the European Medicines Agency (EMA)'s regulatory decision-making on medicines. METHOD: The initiatives were identified from publicly available websites. Their topics were categorised into five areas: 'Data source', 'Methodology', 'Governance model', 'Analytical model' and 'Infrastructure'. To assess their immediate relevance for medicines evaluation, their therapeutic areas were compared with the products recommended for EU approval in 2016 and those included in the EMA pharmaceutical business pipeline. RESULTS: Of 171 originally identified EU-funded initiatives, 65 were selected based on their primary and secondary objectives (35 'Data source' initiatives, 15 'Methodology', 10 'Governance model', 17 'Analytical model' and 25 'Infrastructure'). These 65 initiatives received over 734 million Euros of public funding. At the time of evaluation, the published outputs of the 40 completed initiatives did not always match their original objectives. Overall, public information was limited, data access was not explicit and their sustainability was unclear. The topics matched 8 of 14 therapeutic areas of the products recommended for approval in 2016 and 8 of 15 therapeutic areas in the 2017-2019 pharmaceutical business pipeline. Haematology, gastroenterology or cardiovascular systems were poorly represented. CONCLUSIONS: This landscape of EU-funded initiatives linked to RWE which started before 31 December 2016 highlighted that the immediate utilisation of their outputs to support regulatory decision-making is limited, often due to insufficient available information and to discrepancies between outputs and objectives. Furthermore, the restricted sustainability of the initiatives impacts on their downstream utility. Multiple projects focussing on the same therapeutic areas increase the likelihood of duplication of both efforts and resources. These issues contribute to gaps in generating RWE for medicines and diminish returns on the public funds invested.

Endothelial NADPH oxidase-2 promotes interstitial cardiac fibrosis and diastolic dysfunction through proinflammatory effects and endothelial-mesenchymal transition.

OBJECTIVES: This study sought to investigate the effect of endothelial dysfunction on the development of cardiac hypertrophy and fibrosis. BACKGROUND: Endothelial dysfunction accompanies cardiac hypertrophy and fibrosis, but its contribution to these conditions is unclear. Increased nicotinamide adenine dinucleotide phosphate oxidase-2 (NOX2) activation causes endothelial dysfunction. METHODS: Transgenic mice with endothelial-specific NOX2 overexpression (TG mice) and wild-type littermates received long-term angiotensin II (AngII) infusion (1.1 mg/kg/day, 2 weeks) to induce hypertrophy and fibrosis. RESULTS: TG mice had systolic hypertension and hypertrophy similar to those seen in wild-type mice but developed greater cardiac fibrosis and evidence of isolated left ventricular diastolic dysfunction (p < 0.05). TG myocardium had more inflammatory cells and VCAM-1-positive vessels than did wild-type myocardium after AngII treatment (both p < 0.05). TG microvascular endothelial cells (ECs) treated with AngII recruited 2-fold more leukocytes than did wild-type ECs in an in vitro adhesion assay (p < 0.05). However, inflammatory cell NOX2 per se was not essential for the profibrotic effects of AngII. TG showed a higher level of endothelial-mesenchymal transition (EMT) than did wild-type mice after AngII infusion. In cultured ECs treated with AngII, NOX2 enhanced EMT as assessed by the relative expression of fibroblast versus endothelial-specific markers. CONCLUSIONS: AngII-induced endothelial NOX2 activation has profound profibrotic effects in the heart in vivo that lead to a diastolic dysfunction phenotype. Endothelial NOX2 enhances EMT and has proinflammatory effects. This may be an important mechanism underlying cardiac fibrosis and diastolic dysfunction during increased renin-angiotensin activation.

Nox2 is required for macrophage chemotaxis towards CSF-1.

Macrophage migration and infiltration is an important first step in many pathophysiological processes, in particular inflammatory diseases. Redox modulation of the migratory signalling processes has been reported in endothelial cells, vascular smooth muscle cells and fibroblasts. However the redox modulation of the migratory process in macrophages and in particular that from the NADPH oxidase-2 (Nox2) dependent ROS has not been established. To investigate the potential role of Nox2 in the migratory response of macrophages, bone marrow derived macrophages were obtained from WT and NOX2 knockout mice (Nox2KO) and subjected to CSF-1 stimulation. We report here that loss of Nox2 expression in BMM resulted in a significant reduction in the CSF-1 induced spreading response suggesting that Nox2 can modulate cytoskeletal events. Moreover, Nox2KO BMMs were deficient in cellular displacement in the presence of CSF-1. More significantly, when challenged with a gradient of CSF-1, Nox2KO BMMs showed a complete loss of chemotaxis accompanied by a reduction in cell migration speed and directional migration persistence. These results point to a specific role for Nox2KO downstream of CSF-1 during the BMM migratory response. Indeed, we have further found that Nox2KO BMMs display a significant reduction in the levels of ERK1/2 phosphorylation following stimulation with CSF-1.Thus Nox2 is important in BMM cellular motion to CSF-1 stimulation and necessary for their directed migration towards a CSF-1 gradient, highlighting Nox2 dependent signalling as a potential anti-inflammatory target.

Endothelial Nox4 NADPH oxidase enhances vasodilatation and reduces blood pressure in vivo.

OBJECTIVE: Increased reactive oxygen species (ROS) production is involved in the pathophysiology of endothelial dysfunction. NADPH oxidase-4 (Nox4) is a ROS-generating enzyme expressed in the endothelium, levels of which increase in pathological settings. Recent studies indicate that it generates predominantly hydrogen peroxide (H(2)O(2)), but its role in vivo remains unclear. METHODS AND RESULTS: We generated transgenic mice with endothelium-targeted Nox4 overexpression (Tg) to study the in vivo role of Nox4. Tg demonstrated significantly greater acetylcholine- or histamine-induced vasodilatation than wild-type littermates. This resulted from increased H(2)O(2) production and H(2)O(2)-induced hyperpolarization but not altered nitric oxide bioactivity. Tg had lower systemic blood pressure than wild-type littermates, which was normalized by antioxidants. CONCLUSION: Endothelial Nox4 exerts potentially beneficial effects on vasodilator function and blood pressure that are attributable to H(2)O(2) production. These effects contrast markedly with those reported for Nox1 and Nox2, which involve superoxide-mediated inactivation of nitric oxide. Our results suggest that therapeutic strategies to modulate ROS production in vascular disease may need to separately target individual Nox isoforms.

The use of long acting ß2-agonists, alone or in combination with inhaled corticosteroids, in chronic obstructive pulmonary disease (COPD): a risk-benefit analysis.

Chronic obstructive pulmonary disease (COPD) is a slowly progressive, largely non-reversible pulmonary disease which is characterised by airflow limitation. It is one of the few diseases with an increasing mortality rate and by 2020 it is predicted to be the third leading cause of death. The mainstays of current treatment are long acting ß2 agonists (LABAs) coupled with an increasing reliance on inhaled corticosteroids (ICS). Two LABAs (salmeterol and formoterol) are currently licensed for COPD both as monotherapy and in combination with ICS (fluticasone propionate (FP) and budesonide respectively). A comprehensive review of the risk-benefit of these medicines in COPD is provided here which concludes that there is limited efficacy for LABAs in COPD either alone or in combination with ICS and no overall modification of the disease process. However, where directly compared, combination therapy usually provides an advantage over monotherapy. Importantly the apparent effectiveness of treatment may significantly depend upon the outcome measure chosen with some measures possibly underestimating the extent of benefit. ICS benefit may also be greater in those patients who respond to treatment. Set against this benefit are recent concerns that a number of issues related to the clinical trial design such as prior use of ICS and different withdrawal rates between groups may be significantly influencing results. Furthermore there is no evidence of a dose response relationship with regard to ICS dose. A key issue with combination therapy is the excess risk of pneumonia conferred by the use of an ICS in this patient population. This risk does not appear to be proportional to the ICS dose but may differ between FP and budesonide. We conclude that further studies are required to identify the optimal dose of ICS, in terms of both risk and benefit, and to confirm their benefit in steroid naïve patients. Furthermore it will be important to determine whether the risk of pneumonia is apparent with both FP and budesonide and to identify factors which may predict steroid responsiveness in COPD.

Protein phosphatase 2A contributes to the cardiac dysfunction induced by endotoxemia.

AIMS: Sepsis-associated cardiac dysfunction represents an intrinsic impairment of cardiomyocyte function due in part to a decrease in myofilament Ca(2+) sensitivity associated with a sustained increase in cardiac troponin I (cTnI) phosphorylation at Ser23/24. Dephosphorylation of cTnI is under regulatory control. Thus, muscarinic and adenosine A(1)-receptor agonists antagonize beta-adrenergic stimulation via activation of protein phosphatase 2A (PP2A). The aim of this study was to determine whether modulation of PP2A and thus cTnI phosphorylation could improve sepsis-induced contractile dysfunction. METHODS AND RESULTS: Cardiomyocytes were isolated from control or septic mice 16-18 h after an injection of vehicle or lipopolysaccharide (LPS; 9 mg/kg ip) respectively. Protein expression and phosphatase activity were determined in homogenates of control and septic hearts. Our data showed that LPS significantly increased cTnI phosphorylation at Ser23/24 in cardiomyocytes and reduced contraction amplitude without affecting Ca(2+)-transients. Treatment of cardiomyocytes with the A(1) agonist cyclopentyladenosine (CPA) or the protein kinase A inhibitor H89 significantly attenuated the LPS-induced contractile dysfunction without effect on Ca(2+)-transients. Co-treatment with CPA and H89 completely reversed the contractile dysfunction. Increased cTnI phosphorylation in septic hearts was associated with a significant reduction in the protein expression of both the catalytic and regulatory subunits (B56 alpha) of PP2A and a decrease in PP2A activity. CPA treatment of septic hearts increased PP2A activity. An increase in the protein expression of demethylated PP2A and a decrease in the PP2A-methyltransferase (PPMT; the methyltransferase that catalyses this reaction) were also observed. CONCLUSION: These data support the hypothesis that sustained cTnI phosphorylation underlies the contractile dysfunction seen in sepsis.

Selective targeting of NADPH oxidase for cardiovascular protection.

The NADPH oxidase is a ubiquitously distributed multisubunit enzyme which generates superoxide from molecular oxygen using NADPH as the electron donor. In cardiovascular cells the main catalytic unit consists of two subunits, p22(phox) and one of five Nox isoforms, of which Nox1, Nox2 and Nox4 are the main isoforms expressed in cardiovascular cells. Nox1 and Nox2 require the association with cytosolic subunits for activity, whereas Nox4 appears to be constitutively active. Not only does the expression profile of these isoforms differ between different cell types, but individual isoforms appear to have distinct and separate locations within the cell. Nox enzymes have been linked to a range of cardiovascular pathologies including cardiac and vascular hypertrophy and fibrosis, atherosclerosis, vascular inflammation and angiogenesis, in addition to cellular proliferation and differentiation. Moreover, it is becoming increasingly clear that the individual Nox isoforms have delineated roles within the cell and are linked with specific downstream effects. This review will highlight some of the most important recent studies and discuss how specifically targeting the subunits of the NADPH oxidase complex may have therapeutic potential.

Involvement of Nox2 NADPH oxidase in adverse cardiac remodeling after myocardial infarction.

Oxidative stress plays an important role in the development of cardiac remodeling after myocardial infarction (MI), but the sources of oxidative stress remain unclear. We investigated the role of Nox2-containing reduced nicotinamide-adenine dinucleotide phosphate oxidase in the development of cardiac remodeling after MI. Adult Nox2(-/-) and matched wild-type (WT) mice were subjected to coronary artery ligation and studied 4 weeks later. Infarct size after MI was similar in Nox2(-/-) and WT mice. Nox2(-/-) mice exhibited significantly less left ventricular (LV) cavity dilatation and dysfunction after MI than WT mice (eg, echocardiographic LV end-diastolic volume: 75.7+/-5.8 versus 112.4+/-12.3 microL; ejection fraction: 41.6+/-3.7 versus 32.9+/-3.2%; both P<0.05). Similarly, in vivo LV systolic and diastolic functions were better preserved in Nox2(-/-) than WT mice (eg, LV dP/dt(max): 7969+/-385 versus 5746+/-234 mm Hg/s; LV end-diastolic pressure: 12.2+/-1.3 versus 18.0+/-1.8 mm Hg; both P<0.05). Nox2(-/-) mice exhibited less cardiomyocyte hypertrophy, apoptosis, and interstitial fibrosis; reduced increases in expression of connective tissue growth factor and procollagen 1 mRNA; and smaller increases in myocardial matrix metalloproteinase-2 activity than WT mice. These data suggest that the Nox2-containing reduced nicotinamide-adenine dinucleotide phosphate oxidase contributes significantly to the processes underlying adverse cardiac remodeling and contractile dysfunction post-MI.

NADPH oxidases in cardiovascular health and disease.

Increased oxidative stress plays an important role in the pathophysiology of cardiovascular diseases such as hypertension, atherosclerosis, diabetes, cardiac hypertrophy, heart failure, and ischemia-reperfusion. Although several sources of reactive oxygen species (ROS) may be involved, a family of NADPH oxidases appears to be especially important for redox signaling and may be amenable to specific therapeutic targeting. These include the prototypic Nox2 isoform-based NADPH oxidase, which was first characterized in neutrophils, as well as other NADPH oxidases such as Nox1 and Nox4. These Nox isoforms are expressed in a cell- and tissue-specific fashion, are subject to independent activation and regulation, and may subserve distinct functions. This article reviews the potential roles of NADPH oxidases in both cardiovascular physiological processes (such as the regulation of vascular tone and oxygen sensing) and pathophysiological processes such as endothelial dysfunction, inflammation, hypertrophy, apoptosis, migration, angiogenesis, and vascular and cardiac remodeling. The complexity of regulation of NADPH oxidases in these conditions may provide the possibility of targeted therapeutic manipulation in a cell-, tissue- and/or pathway-specific manner at appropriate points in the disease process.

Aldosterone mediates angiotensin II-induced interstitial cardiac fibrosis via a Nox2-containing NADPH oxidase.

Angiotensin (ANG) II (AngII) and aldosterone contribute to the development of interstitial cardiac fibrosis. We investigated the potential role of a Nox2-containing NADPH oxidase in aldosterone-induced fibrosis and the involvement of this mechanism in AngII-induced effects. Nox2-/- mice were compared with matched wild-type controls (WT). In WT mice, subcutaneous (s.c.) AngII (1.1 mg/kg/day for 2 wk) significantly increased NADPH oxidase activity, interstitial fibrosis (11.5+/-1.0% vs. 7.2+/-0.7%; P<0.05), expression of fibronectin, procollagen I, and connective tissue growth factor mRNA, MMP-2 activity, and NF-kB activation. These effects were all inhibited in Nox2-/- hearts. The mineralocorticoid receptor antagonist spironolactone inhibited AngII-induced increases in NADPH oxidase activity and the increase in interstitial fibrosis. In a model of mineralocorticoid-dependent hypertension involving chronic aldosterone infusion (0.2 mg/kg/day) and a 1% Na Cl diet ("ALDO"), WT animals exhibited increased NADPH oxidase activity, pro-fibrotic gene expression, MMP-2 activity, NF-kB activation, and significant interstitial cardiac fibrosis (12.0+/-1.7% with ALDO vs. 6.3+/-0.3% without; P<0.05). These effects were inhibited in Nox2-/- ALDO mice (e.g., fibrosis 6.8+/-0.8% with ALDO vs. 5.8+/-1.0% without ALDO; P=NS). These results suggest that aldosterone-dependent activation of a Nox2-containing NADPH oxidase contributes to the profibrotic effect of AngII in the heart as well as the fibrosis seen in mineralocorticoid-dependent hypertension.

NADPH oxidase-dependent redox signalling in cardiac hypertrophy, remodelling and failure.

Markers of increased oxidative stress are known to be elevated following acute myocardial infarction and in the context of chronic left ventricular hypertrophy or heart failure, and their levels may correlate with the degree of contractile dysfunction or cardiac deficit. An obvious pathological mechanism that may account for this correlation is the potential deleterious effects of increased oxidative stress through the induction of cellular dysfunction, energetic deficit or cell death. However, reactive oxygen species have several much more subtle effects in the remodelling or failing heart that involve specific redox-regulated modulation of signalling pathways and gene expression. Such redox-sensitive regulation appears to play important roles in the development of several components of the phenotype of the failing heart, for example cardiomyocyte hypertrophy, interstitial fibrosis and chamber remodelling. In this article, we review the evidence supporting the involvement of reactive oxygen species and redox signalling pathways in the development of cardiac hypertrophy and heart failure, with a particular focus on the NADPH oxidase family of superoxide-generating enzymes which appear to be especially important in redox signalling.

Glycated proteins stimulate reactive oxygen species production in cardiac myocytes: involvement of Nox2 (gp91phox)-containing NADPH oxidase.

BACKGROUND: Nonenzymatic glycation that results in the production of early-glycation Amadori-modified proteins and advanced-glycation end products may be important in the pathogenesis of diabetic complications. However, the effects of early-glycated proteins, such as glycated serum albumin (Gly-BSA), are poorly defined. In this study, we investigated the effects of Gly-BSA on reactive oxygen species (ROS) production by cardiomyocytes. METHODS AND RESULTS: Cultured neonatal rat cardiomyocytes were incubated with Gly-BSA or vehicle (bovine serum albumin [BSA]) for up to 48 hours. Gly-BSA dose-dependently increased in situ ROS production (whole-cell dichlorodihydrofluorescein fluorescence), with an optimum effect at 400 microg/mL after 24-hour incubation (152+/-10% versus BSA 100%; P<0.01). Treatment with the NADPH oxidase inhibitor apocynin, a Nox2 (gp91phox) antisense oligonucleotide (Nox2 AS), or the peptide gp91ds-tat significantly reduced Gly-BSA-induced ROS production at 24 hours (68.5+/-2.2%, 61.4+/-8.3%, and 53.2+/-5.4% reduction, respectively). NADPH-dependent activity in cell homogenates was also significantly increased by Gly-BSA at 24 hours (161+/-8% versus BSA) and was inhibited by diphenyleneiodonium, apocynin, NOX2AS, and the protein kinase C inhibitor bisindolylmaleimide I but not by a nitric oxide synthase inhibitor or mitochondrial inhibitors. Furthermore, bisindolylmaleimide I prevented Gly-BSA-stimulated Rac1 translocation, an essential step for NADPH oxidase activation. Gly-BSA-induced increases in ROS were associated with apocynin-inhibitable nuclear translocation of nuclear factor-kappaB and an increase in atrial natriuretic factor mRNA expression. CONCLUSIONS: Gly-BSA stimulates cardiomyocyte ROS production through a protein kinase C-dependent activation of a Nox2-containing NADPH oxidase, which results in nuclear factor-kappaB activation and upregulation of atrial natriuretic factor mRNA. These findings suggest that early-glycated Amadori products may play a role in the development of diabetic heart disease.