Measurement of ischaemia–reperfusion in patients with intermittent claudication using NMR‐based metabonomics

Abstract

Intermittent claudication has proved to be a good in vivo model for ischaemia-reperfusion. For assessment of ischaemia-reperfusion damage, the known biochemical markers all have disadvantages with respect to sensitivity and interference with other physiological events. In this work, we studied the metabolic effects of ischaemia-reperfusion in patients with intermittent claudication, and the effects of vitamin C and E intervention, using both traditional biochemical measurements and 1H-NMR-based metabonomics on urine and plasma. The 1H-NMR spectra were subjected to multivariate modelling using principal components discriminant analysis, and the observed clusters were validated using joint deployment of univariate analysis of variance and Tukey-Kramer honestly significant difference (HSD) testing. The study involved 14 patients with intermittent claudication and three healthy volunteers, who were monitored during a walking test, before and after a vitamin C/E intervention, and after a washout period. The effect of exercise was only observable for a limited number of biochemical markers, whereas 1H NMR revealed an effect in line with anaerobic ATP production via glycolysis in exercising (ischaemic) muscle of the claudicants. Thus, the beneficial effect of vitamins C and E in claudicants was more pronounced when observed by metabonomics than by traditional biochemical markers. The main effect was more rapid recovery from exercise to resting state metabolism. Furthermore, after intervention, claudicants tended to have lower concentrations of lactate and glucose and several other citric acid cycle metabolites, whereas acetoacetate was increased. The observed metabolic changes in the plasma suggest that intake of vitamin C/E leads to increased muscle oxidative metabolism.

Standard operating procedures for pre-analytical handling of blood and urine for metabolomic studies and biobanks

“…Such spectra, often called metabolic profile, constitute a ''fingerprint'' of the NMR detectable part of the whole metabolome. The potential of metabolomics for disease diagnosis, prognosis and, in a clinical trial setting, for monitoring drug therapy relies on its ability to extract a disease signature from the multivariate analysis of the metabolic profiles of statistically relevant ensembles of samples derived from different donors (Oakman et al 2010;Sreekumar et al 2009;Bertini et al 2009;Akira et al 2008;Holmes et al 2008;Bartsch et al 2008;Gao et al 2008;Fearnside et al 2008;Makinen et al 2008;Teichert et al 2008;Coolen et al 2008;Claudino et al 2007;Schnackenberg et al 2007;Marchesi et al 2007;Griffin et al 2007;Constantinou et al 2007;Coen et al 2005;Lindon et al 2004;Brindle et al 2002). Clearly, the reliability of the approach requires that the chemical nature and the relative concentration of all the metabolites present in the biofluids are neither affected by the preanalytical treatment used to store the samples nor by the analytical methodology.…”

Urinary metabonomic study of lung cancer by a fully automatic hyphenated hydrophilic interaction/RPLC‐MS system

“…, to reveal the systemic aspects of biological processes. NMR 22–24 and MS methods hyphenated with chromatographic separation (LC, GC, etc. ) 25–28 are generally used in metabonomic studies.…”

Application of 1H-NMR-based metabolomics for detecting injury induced by long-term microwave exposure in Wistar rats’ urine

“…The level of ketone bodies increases when acetylCoA derived from β-oxidation of free fatty acid exceeds the metabolic capacity of the TCA cycle. Acetate is also an end product of fatty acid oxidation (degradation of short-chain fatty acid: acetoacetate + acetyl-CoA → acetoacetyl-CoA + acetate) [17][18][19]. The levels of acetate in urine were increased at 21 days after 5 mW/cm 2 long-term microwave exposure, suggesting a shift in the balance of energy metabolism from ketone body formation toward utilization during this period.…”