Measurement of sulfur compounds in the liver. (a) Quantification of sulfur compounds in the liver homogenates of control mice on Earth (GC), mice under artificial earth-gravity in space (A1G), and mice under microgravity in space (MG). GS, Glutathione; GSSG, glutathione disulfide; PAP, 3′-phosphoadenosine-5′-phosphosulfate; APS, adenosine-5′-phosphosulfate. ‘S-Bimanyl-’ indicates that the compounds were detected as bimane-derivates. Each horizontal bar represents the mean. *P < 0.05. Comparisons of parameters were performed with one-way ANOVA followed by Dunnett’s test for multiple comparisons (n = 6 each). Dot plots were made using GraphPad Prism 6.07 for Windows, GraphPad Software, San Diego, CA USA, www.graphpad.com. (b) Heatmap and hierarchical clustering were performed in R. The red color intensity correlates with the relative signal abundance. (c) Spatial placement of crowds on a non-metric multidimensional scaling (NMDS) using the Bray index. NMDS analysis, using the “vegan” package in R to analyze similarity indices, was performed on normalized metabolomics data that was subsequently log-transformed and auto-scaled31,32. The first two coordinates were plotted. PC principal coordinate.