Background: Fatty acid (FA) metabolism is suppressed under conditions of cardioplegic arrest, but the mechanism behind this effect is unknown. We hypothesized that alterations in redox state and oxygen demand control myocardial FA utilization during potassium arrest.
Methods: Rat hearts were perfused with Krebs-Heinseleit buffer containing physiologic concentrations of FAs, ketones, and carbohydrates with unique (13)Carbon labeling patterns. Cytosolic and mitochondrial redox states were altered by manipulating the lactate/pyruvate and ketone redox couples, respectively. Myocardial oxygen consumption was increased by adding the mitochondrial uncoupler 2,4-dinitrophenol to the perfusate. Experiments were conducted under conditions of normokalemic perfusion and potassium cardioplegia (PC). Substrate oxidation rates were derived from (13)Carbon isotopomer data and myocardial oxygen consumption.
Results: Continuous perfusion under conditions of potassium arrest dramatically reduced fatty acid oxidation. Both the addition of 2,4-dinitrophenol and alteration of mitochondrial redox state significantly increased FA oxidation during PC. In contrast to normokalemic perfusion, altering cytosolic redox state during PC did not change FA oxidation.
Conclusions: These data suggest that mitochondrial redox state and oxygen demand are important determinants of myocardial FA oxidation during potassium arrest. FA oxidation appears to be regulated by different factors during PC than normokalemic perfusion.
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http://dx.doi.org/10.1016/j.surg.2004.04.007 | DOI Listing |
Biosens Bioelectron
January 2025
Department of Chemistry, Kansas State University, Manhattan, KS, 66502, USA. Electronic address:
Proteases are overexpressed at various stages of conditions such as cancers and thus can serve as biomarkers for disease diagnosis. Electrochemical techniques to detect the activity of extracellular proteases have gained attraction due to their multiplexing capability. Here we employ an electrochemical approach based on a 3 × 3 gold (Au) microelectrode array (MEA) functionalized with (2-aminoethyl)ferrocene (AEF) tagged specific peptide substrates to monitor cathepsin B (CB) protease activity.
View Article and Find Full Text PDFNanomedicine
January 2025
Center for Research Development and Evaluation of Pharmaceutical Excipients and Generic Drugs, China Pharmaceutical University, Nanjing, China; State Key Laboratory of Nature Medicines, Department of Pharmaceutics, China Pharmaceutical University, Nanjing, China. Electronic address:
Sci Rep
January 2025
Department of Biochemistry, College of Science, King Saud University, P.O.Box 2455, Riyadh, 11451, Saudi Arabia.
Nano-biochar considers a versatile and valuable sorbent to enhance plant productivity by improving soil environment and emerged as a novel solution for environmental remediation and sustainable agriculture in modern era. In this study, roles of foliar applied nanobiochar colloidal solution (NBS) on salt stressed tomato plants were investigated. For this purpose, NBS was applied (0%, 1% 3% and 5%) on two groups of plants (control 0 mM and salt stress 60 mM).
View Article and Find Full Text PDFCell Death Dis
January 2025
CECAD Cluster of Excellence, University of Cologne, Cologne, Germany.
Constitutive mitochondrial dynamics ensure quality control and metabolic fitness of cells, and their dysregulation has been implicated in various human diseases. The large GTPase Dynamin-related protein 1 (Drp1) is intimately involved in mediating constitutive mitochondrial fission and has been implicated in mitochondrial cell death pathways. During ferroptosis, a recently identified type of regulated necrosis driven by excessive lipid peroxidation, mitochondrial fragmentation has been observed.
View Article and Find Full Text PDFRedox Biol
January 2025
Department of Reproductive Medicine, Jinling Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, Jiangsu, 210002, China; State Key Laboratory of Reproductive Medicine and Offspring Health, Nanjing Medical University, Nanjing, Jiangsu, 211166, China; Department of Reproductive Medicine, Affiliated Jinling Hospital, The First School of Clinical Medicine, Southern Medical University, Nanjing, 210002, China. Electronic address:
Oocyte aging is closely related to a decline in female fertility, accompanied by increased reactive oxygen species levels and changes in protein posttranslational modifications. However, the role of protein palmitoylation in oocyte aging has not been investigated. In the present study, a new association between redox and palmitoylation in aging oocytes was found.
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