13 research outputs found

    Relative Contribution of Different Upper Glycolytic Components in the Maintenance of the Retinal Vascular Endothelial Cell Barrier

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    Introduction: Damage to the retinal vascular endothelium is implicated in the progression of retinal degenerative diseases, including diabetic retinopathy (DR) and diabetic macular edema (DME). The retinal endothelial cells constitute the inner blood-retinal barrier (iBRB), and disruption of this barrier allows for the dysregulation of fluid and solute passage into the retina. Moreover, under normal physiological conditions, glycolytic metabolism is critical to the functioning of endothelial cells and maintenance of the iBRB. Conversely, in hyperglycemic environments, unregulated glycolytic metabolism leads to a buildup of glycolytic intermediates, which is thought to contribute to disruption of the iBRB and is associated with retinal cell damage and neovascularization. However, the metabolic mechanisms underlying these processes remain unclear. In this study, we looked to further characterize the roles of upper glycolytic enzymes, those involved in the ATP consumption phase of glycolysis, in the maintenance of the iBRB. Methods: Electric cell-substrate impedance sensing (ECIS) technology was used to assess in real-time the role of different glycolytic enzymes in maintaining the barrier functionality of human retinal endothelial cells (HREC). Furthermore, the endothelial cellular viability was assessed through lactate dehydrogenase cytotoxicity assay following 24h, 48h, and 72h time intervals. Results: Inhibition with heptelidic acid (glyceraldehyde-3-phosphate dehydrogenase (GA3PDH) inhibitor) significantly reduced the resistance (R) and thus the integrity of the HREC barrier at concentrations of 1.0 μM and 10 μM. PFK158 (phosphofructokinase-1 (PFK1) inhibitor) also significantly reduced R, but only at a concentration of 10 μM. Similarly, administration of PFK158 reduced HREC viability throughout all three time intervals (24h, 48h, and 72h) at a concentration of 10 μM. However, administration of heptelidic acid showed reduced HREC viability only at the 72h time interval, but also at a concentration of 10 μM. The other inhibitors tested did not demonstrate significant reduction in resistance of the HREC barrier or in cellular viability. Conclusion: Our study demonstrates the differential roles of glycolytic enzymes in maintaining the barrier functionality of HRECs. We specifically showed that the functions of GA3PDH and PFK-1 are the most important components in regulating HREC barrier integrity. These observed differences are significant since they could serve as the basis for future pharmacological and gene expression studies aiming to improve the activity of GA3PDH and PFK1 and thereby provide avenues for therapeutic modalities in endothelial-associated retinal diseases

    A Novel Criticality Analysis Method for Assessing Obesity Treatment Efficacy

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    This is the final version. Available on open access from MDPI via the DOI in this recordData Availability Statement: In accordance with the General Data Protection Regulation (GDPR) guidelines, the database utilised in this study is maintained in a confidential and secure manner within the purview of the Faculty of Health and Life Sciences at Oxford Brookes University. Owing to privacy considerations, access to the dataset is restricted to authorised personnel only.Human gait is a significant indicator of overall health and well-being due to its dependence on metabolic requirements. Abnormalities in gait can indicate the presence of metabolic dysfunction, such as diabetes or obesity. However, detecting these can be challenging using classical methods, which often involve subjective clinical assessments or invasive procedures. In this work, a novel methodology known as Criticality Analysis (CA) was applied to the monitoring of the gait of teenagers with varying amounts of metabolic stress who are taking part in an clinical intervention to increase their activity and reduce overall weight. The CA approach analysed gait using inertial measurement units (IMU) by mapping the dynamic gait pattern into a nonlinear representation space. The resulting dynamic paths were then classified using a Support Vector Machine (SVM) algorithm, which is well-suited for this task due to its ability to handle nonlinear and dynamic data. The combination of the CA approach and the SVM algorithm demonstrated high accuracy and non-invasive detection of metabolic stress. It resulted in an average accuracy within the range of 78.2% to 90%. Additionally, at the group level, it was observed to improve fitness and health during the period of the intervention. Therefore, this methodology showed a great potential to be a valuable tool for healthcare professionals in detecting and monitoring metabolic stress, as well as other associated disorders.Newton Fun

    Can public health reconcile profits and pandemics? An analysis of attitudes to commercial sector engagement in health policy and research

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    Public health's terms of engagement with unhealthy commodity industries (alcohol, tobacco and ultra-processed food and drinks) have become increasingly contested in policy and research. We sought to identify approaches that could attract consensus support within and across policy domains.Using snowball sampling, we undertook an online survey of 335 health researchers, advocates and policymakers, in 40 countries, assessing responses to stated principles, claims and recommendations for engaging with unhealthy commodity industries in relation to key policy and research initiatives.Most respondents identified a fundamental conflict between industry interests and public health objectives for all three industries, with agreement greatest in relation to tobacco and weakest for food. This pattern was replicated across diverse questions regarding potential forms of engagement, including in rejecting voluntarism and partnership approaches to health policy. While awareness of tobacco industry tactics to influence policy and research was higher than for alcohol and food, most respondents rejected the view that the influence of the latter was less significant for public health. Proposals that health and research organisations should divest their funds attracted less support with respect to food, while restricting publication of industry-funded research in academic journals was the issue that most divided opinion. Respondents reported most difficulty in answering questions about the food industry.The strong consensus around restricting interactions with the tobacco industry supports increased implementation of the WHO Framework Convention on Tobacco Control's conflict of interest provisions. There is strong support for the extension of such practices to the alcohol industry, challenging current norms. More mixed responses indicate a need for greater clarity in defining the food industry, and for research analyzing links, similarities and differences across different types of unhealthy commodity producers. Partnership approaches to addressing non-communicable diseases seem incapable of attracting widespread support across public health, challenging practice in many contexts

    Mediator complex (MED) 7: a biomarker associated with good prognosis in invasive breast cancer, especially ER+ luminal subtypes

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    Background: Mediator complex (MED) proteins have a key role in transcriptional regulation, some interacting with the oestrogen receptor (ER). Interrogation of the METABRIC cohort suggested that MED7 may regulate lymphovascular invasion (LVI). Thus MED7 expression was assessed in large breast cancer (BC) cohorts to determine clinicopathological significance. Methods: MED7 gene expression was investigated in the METABRIC cohort (n = 1980) and externally validated using bc-GenExMiner v4.0. Immunohistochemical expression was assessed in the Nottingham primary BC series (n = 1280). Associations with clinicopathological variables and patient outcome were evaluated. Results: High MED7 mRNA and protein expression was associated with good prognostic factors: low grade, smaller tumour size, good NPI, positive hormone receptor status (p < 0.001), and negative LVI (p = 0.04) status. Higher MED7 protein expression was associated with improved BC-specific survival within the whole cohort and ER+/luminal subgroup. Pooled MED7 gene expression data in the external validation cohort confirmed association with better survival, corroborating with the protein expression. On multivariate analysis, MED7 protein was independently predictive of longer BC-specific survival in the whole cohort and Luminal A subtype (p < 0.001). Conclusions: MED7 is an important prognostic marker in BC, particularly in ER+luminal subtypes, associated with improved survival and warrants future functional analysis

    Relative Importance of Different Elements of Mitochondrial Oxidative Phosphorylation in Maintaining the Barrier Integrity of Retinal Endothelial Cells: Implications for Vascular-Associated Retinal Diseases

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    Purpose: Mitochondrial dysfunction is central to breaking the barrier integrity of retinal endothelial cells (RECs) in various blinding eye diseases such as diabetic retinopathy and retinopathy of prematurity. Therefore, we aimed to investigate the role of different mitochondrial constituents, specifically those of oxidative phosphorylation (OxPhos), in maintaining the barrier function of RECs. Methods: Electric cell-substrate impedance sensing (ECIS) technology was used to assess in real time the role of different mitochondrial components in the total impedance (Z) of human RECs (HRECs) and its components: capacitance (C) and the total resistance (R). HRECs were treated with specific mitochondrial inhibitors that target different steps in OxPhos: rotenone for complex I, oligomycin for complex V (ATP synthase), and FCCP for uncoupling OxPhos. Furthermore, data were modeled to investigate the effects of these inhibitors on the three parameters that govern the total resistance of cells: Cell&ndash;cell interactions (Rb), cell&ndash;matrix interactions (&alpha;), and cell membrane permeability (Cm). Results: Rotenone (1 &micro;M) produced the greatest reduction in Z, followed by FCCP (1 &micro;M), whereas no reduction in Z was observed after oligomycin (1 &micro;M) treatment. We then further deconvoluted the effects of these inhibitors on the Rb, &alpha;, and Cm parameters. Rotenone (1 &micro;M) completely abolished the resistance contribution of Rb, as the Rb became zero immediately after the treatment. Secondly, FCCP (1 &micro;M) eliminated the resistance contribution of Rb only after 2.5 h and increased Cm without a significant effect on &alpha;. Lastly, of all the inhibitors used, oligomycin had the lowest impact on Rb, as evidenced by the fact that this value became similar to that of the control group at the end of the experiment without noticeable effects on Cm or &alpha;. Conclusion: Our study demonstrates the differential roles of complex I, complex V, and OxPhos coupling in maintaining the barrier functionality of HRECs. We specifically showed that complex I is the most important component in regulating HREC barrier integrity. These observed differences are significant since they could serve as the basis for future pharmacological and gene expression studies aiming to improve the activity of complex I and thereby provide avenues for therapeutic modalities in endothelial-associated retinal diseases

    DJ-1 could predict worse prognosis in esophageal squamous cell carcinoma

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    Recent studies have revealed an oncogenic role of DJ-1 through its ability to transform normal cells, prevent oxidative damage, and inhibit apoptosis. However, its role in esophageal squamous cell carcinoma (ESCC) is unknown. In this study, by immunohistochemistry, we analyzed the expression of DJ-1 in 81 ESCC tumors, 31 paired nonneoplastic esophageal epithelia, and 19 paired ESCC lymph node metastases. We found that cytoplasmic DJ-1 expression was significantly higher in ESCC and ESCC lymph node metastases than in nonneoplastic esophageal epithelium. ESCC specimens with high distant metastatic potentialal so had a significantly higher level of nuclear DJ-1 expression (P = 0.018). By Kaplan-Meier analysis, we found that a high level of nuclear DJ-1 was significantly associated with poorer patient survival in our cohort (P = 0.028). To investigate whether DJ-1 promotes ESCC progression through phosphatidylinositol 3-kinase pathway and modulation of apoptosis, we performed immunohistochemistry of pAkt and Daxx. We found that DJ-1 expression was significantly associated with pAkt, whereas nuclear DJ-1 expression was significantly correlated with nuclear expression of Daxx. These results suggest that phosphatidylinositol 3-kinase pathway and Daxx-regulated apoptosis might be important in DJ-1-mediated ESCC progression. By using multivariate Cox regression, we further showed that T4 stage (P = 0.003) and DJ-1 (P = 0.034) are independent predictors of patient survival. In conclusion, our results suggest that DJ-1 plays a very important role in transformation and progression of ESCC and may be used as a prognostic marker in ESCC. Copyright © 2008 American Association for Cancer Research.link_to_subscribed_fulltex

    Upper glycolytic components contribute differently in controlling retinal vascular endothelial cellular behavior: Implications for endothelial-related retinal diseases.

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    BackgroundRetinal degenerative diseases such as diabetic retinopathy and diabetic macular edema are characterized by impaired retinal endothelial cells (RECs) functionality. While the role of glycolysis in glucose homeostasis is well-established, its contributions to REC barrier assembly and cell spreading remain poorly understood. This study aimed to investigate the importance of upper glycolytic components in regulating the behavior of human RECs (HRECs).MethodsElectric cell-substrate impedance sensing (ECIS) technology was employed to analyze the real-time impact of various upper glycolytic components on maintaining barrier functionality and cell spreading of HRECs by measuring cell resistance and capacitance, respectively. Specific inhibitors were used: WZB117 to inhibit Glut1/3, lonidamine to inhibit hexokinases, PFK158 to inhibit the PFKFB3-PFK axis, and TDZD-8 to inhibit aldolases. Additionally, the viability of HRECs was evaluated using the lactate dehydrogenase (LDH) cytotoxicity assay.ResultsThe most significant reduction in electrical resistance and increase in capacitance of HRECs resulted from the dose-dependent inhibition of PFKFB3/PFK using PFK158, followed by aldolase inhibition using TDZD-8. LDH level analysis at 24- and 48-hours post-treatment with PFK158 (1 μM) or TDZD-8 (1 and 10 μM) showed no significant difference compared to the control, indicating that the disruption of HRECs functionality was not attributed to cell death. Conversely, inhibiting Glut1/3 with WZB117 had minimal impact on HREC behavior, except at higher concentrations (10 μM) and prolonged exposure. Lastly, inhibiting hexokinase with lonidamine did not noticeably alter HREC cell behavior.ConclusionThis study illustrates the unique impacts of components within upper glycolysis on HREC functionality, emphasizing the crucial role of the PFKFB3/PFK axis in regulating HREC behavior. Understanding the specific contributions of each glycolytic component in preserving normal REC functionality will facilitate the development of targeted interventions for treating endothelial cell dysfunction in retinal disorders while minimizing effects on healthy cells
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