Dynamics of cytochrome oxidase inactivation was studied in ischemic liver tissue using tetramethyl paraphenylene diamine (TMPD-oxidase) and cytochrome c (cytochrome c oxidase) as substrates. The cytochrome c ovidase activity was determined in presence of low concentrations (0.03%) of Triton X-100 (the total activity) and without the detergent (the free activity). Within 60 min after the restriction of oxygen supply to the liver tissue TMPD-oxidase was inactivated almost completely, at the same time cytochrome c oxidase maintained its activity. The free enzymatic activity became equal to the total activity; this phenomenon demonstrated an increased permeability of the external mitochondrial membrane for cytochrome c. The decrease in the TMPD-oxidase activity was considered to be due to the cytochrome c solubilization. This assumption was supported by the experiments, in which the addition of cytochrome c into the incubation mixture restored the enzymatic activity to the initial level. Hypotonic solutions and treatment of mitochondria with phospholipase A were found to simulate the impairment of the organelles in ischemic liver tissue. Increased peroxidation of unsaturated fatty acids in presence of ascorbic acid and ferrous ions was not accompanied by solubilization of cytochrome c.
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Front Cell Dev Biol
January 2025
Department of Liver, Digestive System and Metabolism, Institut d'Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain.
Introduction: Grafts with alcohol-associated liver disease (ALD) subjected to prolonged cold ischaemia from donors after brain death (DBD) are typically unsuitable for transplantation. Here, we investigated the role of growth hormone (GH) in livers with ALD from DBDs and its relationship with vascular endothelial growth factor A (VEGFA) and VEGFB.
Methods: Livers from rats fed ethanol for 6 weeks and with brain death (BD) were cold stored for 24 h and subjected to reperfusion.
Atherosclerosis
December 2024
Department of Clinical Biochemistry, Copenhagen University Hospital - Herlev Gentofte, Herlev, Denmark; The Copenhagen General Population Study, Copenhagen University Hospital - Herlev Gentofte, Herlev, Denmark; Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark. Electronic address:
Background And Aims: Myocardial infarction is a leading cause of death in individuals with non-alcoholic fatty liver disease (NAFLD). The two diseases share elevated very low-density lipoproteins (VLDL) carrying both triglycerides and cholesterol; however, in NAFLD mainly triglycerides accumulate in liver cells while in myocardial infarction mainly cholesterol accumulates in the atherosclerotic plaque. We hypothesized that VLDL triglycerides preferentially associate with risk of NAFLD, while VLDL cholesterol preferentially associates with risk of myocardial infarction.
View Article and Find Full Text PDFFront Neurol
January 2025
Department of Neurosurgical Intensive Care Unit, Henan Provincial People's Hospital, Zhengzhou, China.
Background: The effect of targeted temperature management (TTM) combined with decompressive craniectomy (DC) on poor-grade aneurysmal subarachnoid hemorrhage (aSAH) has not been previously addressed in the literature. This study aims to investigate the therapeutic outcomes of the combination of TTM and DC in patients with poor-grade aSAH.
Methods: This study represents a secondary analysis of the Multicenter Clinical Research on Targeted Temperature Management of Poor-grade Aneurysmal Subarachnoid Hemorrhage (High-Quality TTM for PaSAH), a multicenter prospective study conducted in China.
Nat Commun
January 2025
Institute of Cancer Research, Shenzhen Bay Laboratory, Shenzhen, Guangdong, China.
S-palmitoylation is a reversible and widespread post-translational modification, but its role in the regulation of ferroptosis has been poorly understood. Here, we elucidate that GPX4, an essential regulator of ferroptosis, is reversibly palmitoylated on cysteine 66. The acyltransferase ZDHHC20 palmitoylates GPX4 and increases its protein stability.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
College of Medicine, Lijiang Culture and Tourism College, Lijiang 674100, China. Electronic address:
Gastrodia elata BL. is a dried tuber of the orchid plant Gastrodia R. Br.
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