Fig. 1

MSTN gene expression on day 15 and myostatin plasma trajectory. a MSTN gene expression was significantly decreased in critically ill patients (median [IQR] fold change: 1.00 [0.68–1.54] vs. 0.26 [0.11–0.80]; p = 0.004). b Myostatin plasma concentration over time showed significantly decreased values in critically ill patients. A recovery throughout the first 14 days can be observed (GLM median [IQR] fold change: healthy control vs. day 4 vs. day 8 vs. day 14—median [IQR] 0.99 [0.80–1.20] vs. 0.13 [0.08–0.21] vs. 0.23 [0.10–0.44] vs. 0.40 [0.26–0.61]; p < 0.001; n = 36 patients with values from all three timepoints were analyzed). GLM = general linear model for the factor “time” in critically ill; mRNA = messenger ribonucleic acid. ^###p < 0.001 for Kruskal–Wallis test between healthy controls and critically ill; ***p < 0.001 for post hoc test comparison with healthy controls