Fig. 1
From: Plasma mitochondrial DNA and metabolomic alterations in severe critical illness
Hierarchical clustering of correlated metabolites relative to NADH dehydrogenase 1 (ND1) mitochondrial DNA (mtDNA) group level. Correlation matrix of the 49 major differential metabolites from Additional file 2: Table S1. Cross-sectional correlation colors represent Pearson correlation coefficients of log-transformed metabolites by ND1 mtDNA levels. a ND1 mtDNA < 3200 copies/μl plasma. b ND1 mtDNA ≥ 3200 copies/μl plasma. Glycerophosphocholine and short-chain acylcarnitines are marked in bold. Red and blue indicate positive and negative correlations, respectively. Metabolites with marked differences in the degree of intercorrelation between ND1 mtDNA groups were the glycerophosphocholines (1-stearoylglycerophosphocholine, 2-stearoylglycerophosphocholine, 1-palmitoylglycerophosphocholine) and the short-chain acylcarnitines (isovalerylcarnitine, propionylcarnitine and isobutyrylcarnitine). This analysis allows for the identification and clustering of metabolite modules of related function in patients with low mtDNA and how those correlations are altered in patients with high mtDNA