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Drosatos, K.

Publications and source records attributed to Drosatos, K..

3 recordsLinked to original sources

Shared and Divergent Features of Cardiac Transcriptome and Glucose Metabolism Markers in Human and Mouse HFpEF

Heart Failure with Preserved Ejection Fraction (HFpEF) is more prevalent in females and is associated with altered cardiac glucose metabolism. However, whether these metabolic alterations are conserved across sexes and between humans and widely used cardiometabolic mouse model of HFpEF remains unclear. We investigated species-, sex-, and ventricle-specific conserved and divergent features of HFpEF. Cardiometabolic HFpEF was induced in mice using the 'two-hit' model (high-fat diet + L-NAME), followed by assessment of cardiac function, RNA sequencing, and protein expression in the right (RV) and left (LV) ventricles. Published human HFpEF RV and LV RNA-seq datasets were reanalyzed and compared with our mouse data. Only male HFpEF mice recapitulated human phenotype of increased RV GLUT1 protein. In contrast, mouse GLUT1 was downregulated in RV of females and in the LV of both sexes, whereas GLUT4 protein remained unchanged. Cardiac PDK4 transcript and protein levels increased in the RV and LV of mice. Conversely, human PDK4 mRNA levels were reduced in the RV with HFpEF and unchanged in LV. Cardiac transcriptome analysis in mice revealed extensive alterations in LV, particularly in females, with enrichment of inflammatory pathways. Cross-species analysis demonstrated greater conservation of HFpEF-associated signatures in the RV than the LV. Furthermore, number of differentially expressed transcripts in human LV increased substantially after excluding patients with atrial fibrillation or diabetes. Overall, the RV of the 'two-hit' model more closely resembles human HFpEF. The cardiac transcriptome reflects sexual dimorphism, and conserved signatures are primarily associated with metabolic alteration, mitochondrial dysfunction, and cellular stress.

physiology↗

Isolated Mouse Adult Cardiomyocytes Display Minimal Mitochondrial ATP Demand and Maximal Reliance on Glycolysis

Mitochondrial maladaptation is a hallmark of heart failure, contributing to impaired energy production and contractile dysfunction. Understanding the bioenergetics of cardiomyocytes under healthy and pathological conditions is critical for characterizing mitochondrial maladaptation. While adult cardiomyocytes from rodents are a widely used model, recent studies have reported oligomycin insensitivity in these cells, a phenomenon often overlooked. This has led to incomplete assessments of key bioenergetic parameters, such as ATP-linked respiration and glycolytic capacity, focusing primarily on basal and maximal respiration. In this study, we performed a comprehensive characterization of bioenergetic and glycolytic profiles in three cardiomyocyte models: neonatal rat ventricular myocytes (NRVMs), human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs), and mouse adult cardiomyocytes (mouse ACMs). Our findings demonstrate distinct metabolic adaptations in mouse ACMs, revealing critical insights into mitochondrial function, ATP demand, and glycolytic reliance. These results underscore the importance of selecting appropriate cellular models for studying mitochondrial bioenergetics in cardiac physiology and pathology.

cell biology↗

Comprehensive mapping of local and diaspora scientists: a database and analysis of 63951 Greek scientists

Research policy and planning for a given country may benefit from reliable data on both its scientific workforce as well as the diaspora of scientists for countries with substantial brain drain. Here we use a systematic approach using Scopus to generate a comprehensive country-level database of all scientists in Greece. Moreover, we expand that database to include also Greek diaspora scientists. The database that we have compiled includes 63951 scientists who have published at least 5 papers indexed in Scopus. Of those, 35116 have an affiliation in Greece. We validate the sensitivity and specificity of the database against different control sets of scientists. We also analyze the scientific disciplines of these scientists according to the Science Metrix classification (174 subfield disciplines) and provide detailed data on each of the 63951 scientists using multiple citation indicators and a composite thereof. These analyses demonstrate differential concentrations in specific subfields for the local versus the diaspora cohorts, as well as an advantage of the diaspora cohort in terms of citation indicators especially among top-impact researchers. The approach that we have taken can be applied to map also the scientific workforce of other countries and nations for evaluation, planning and policy purposes.

scientific communication and education↗