Oxidation Process of Adrenaline in Freshly Isolated Rat Cardiomyocytes: Formation of Adrenochrome, Quinoproteins, and GSH Adduct

High concentrations of circulating biogenic catecholamines often exist during the course of several cardiovascular disorders. Additionally, coronary dysfunctions are prominent and frequently related to the ischemic and reperfusion phenomenon (I/R) in the heart, which leads to the release of large amounts of catecholamines, namely adrenaline, and to a sustained generation of reactive oxygen species (ROS). Thus, this work aimed to study the toxicity of adrenaline either alone or in the presence of a system capable of generating ROS [xanthine with xanthine oxidase (X/XO)], in freshly isolated, calcium tolerant cardiomyocytes from adult rats. Studies were performed for 3 h, and cardiomyocyte viability, ATP level, lipid peroxidation, protein carbonylation content, and glutathione status were evaluated, in addition to the formation of adrenaline’s oxidation products and quinoproteins. Intracellular GSH levels were time-dependently depleted with no GSSG formation when cardiomyocytes were exposed to adrenaline or to adrenaline with X/XO. Meanwhile, a time-dependent increase in the rate of formation of adrenochrome and quinoproteins was observed. Additionally, as a new outcome, 5-(glutathion-S-yl)adrenaline, an adrenaline adduct of glutathione, was identified and quantified. Noteworthy is the fact that the exposure to adrenaline alone promotes a higher rate of formation of quinoproteins and glutathione adduct, while adrenochrome formation is favored where ROS production is stimulated. This study shows that the redox status of the surrounding environment greatly influences adrenaline’s oxidation pathway, which may trigger cellular changes responsible for cardiotoxicity

Characterisation of microbial attack on archaeological bone

As part of an EU funded project to investigate the factors influencing bone preservation in the archaeological record, more than 250 bones from 41 archaeological sites in five countries spanning four climatic regions were studied for diagenetic alteration. Sites were selected to cover a range of environmental conditions and archaeological contexts. Microscopic and physical (mercury intrusion porosimetry) analyses of these bones revealed that the majority (68%) had suffered microbial attack. Furthermore, significant differences were found between animal and human bone in both the state of preservation and the type of microbial attack present. These differences in preservation might result from differences in early taphonomy of the bones. © 2003 Elsevier Science Ltd. All rights reserved