Nuclear Magnetic Resonance-Based Metabolomics to Predict Early and Late Adverse Outcomes in Ischemic Stroke Treated with Intravenous Thrombolysis

Abstract

Metabolic perturbations and inflammatory mediators play a fundamental role in both early and late adverse post-acute ischemic stroke outcomes. Using data from the observational MAGIC (MArker bioloGici nell'Ictus Cerebrale) study, we evaluated the effect of 130 serum metabolic features, using a nuclear magnetic spectroscopy approach, on the following outcomes: hemorrhagic transformation at 24 h after stroke, non-response to intravenous thrombolytic treatment with the recombinant tissue plasminogen activator (rt-PA), and the 3 month functional outcome. Blood circulating metabolites, lipoproteins, and inflammatory markers were assessed at the baseline and 24 h after rt-PA treatment. Adjusting for the major determinants for unfavorable outcomes (i.e., age, sex, time onset-to-treatment, etc.), we found that acetone and 3-hydroxybutyrate were associated with symptomatic hemorrhagic transformation and with non-response to rt-PA; while 24 h after rt-PA, levels of triglycerides high-density lipoprotein (HDL) and triglycerides low-density lipoprotein (LDL) were associated with 3 month mortality. Cholesterol and phospholipids levels, mainly related to smaller and denser very low-density lipoprotein (VLDL) and LDL subfractions were associated with 3 month poor functional outcomes. We also reported associations between baseline 24 h relative variation (Δ) in VLDL subfractions and ΔC-reactive protein, Δinterleukin-10 levels with hemorrhagic transformation. All observed metabolic changes reflect a general condition of energy failure, oxidative stress, and systemic inflammation that characterize the development of adverse outcomes.

Keywords: ischemic stroke; lipoproteomics; metabolomics; nuclear magnetic resonance.

Figure 1

Graphical representation of the analysis followed to identify, in serum samples, possible predictors of early and late adverse outcomes of AIS treated with intravenous thrombolysis with rt-PA. Blood samples were collected before (t₁) and 24 h after (t₂) the administration of rt-PA. Early adverse outcomes were defined 24 h after the event, as follows: development of sICH and non-response to the intravenous thrombolysis. Late outcomes [mortality and disability (mRS 3–6)] were defined 3 months after the transient ischemia. For each time point, 1D NMR spectra have been acquired and therefore used to estimate metabolite and lipid concentrations; t₁, t_2, and Δ(pre–post)_rt-PA concentrations of metabolites/lipoprotein.

Figure 2

Scatter plot of PCA, taking into account the first two principal components. The red dots represent the serum metabolic profiles collected before (t₁) the administration of rt-PA, and the green dots represent the serum metabolic profiles collected 24 h after (t₂) the administration of rt-PA.