3 CHAPTER 3 60 CSF concentrations. Four (homocitrulline, S-methylcysteine, methionine sulfone and L-alphaaminobutyric acid) out of 39 amines (10.3%) had a correlation coefficient ≥ .70. These four amines were the same as in healthy controls, and were the same for both MO and MA participants. Overall, there were no clear differences between correlations between the migraine subgroups. Plasma/CSF ratios metabolite correlations Next, we assessed the same metabolite ratios in plasma and CSF, as illustrated in Figure 5 (Table S5). On visual inspection the results largely look the same as obtained for the healthy controls, that is, the correlation of all amines with S-methylcysteine, L-alpha-aminobutyric acid, methionine sulfone, L-threonine and homocitrulline remain high. However, also a clear difference was observed when comparing the correlation matrix plot of healthy controls (Figure 2) and that of participants with migraine (Figure 5). Figure 3 Example of single-metabolite vs. metabolite ratio correlation Concentrations are plotted plasma concentrations on the log10 transformed X-axis and CSF concentrations on the log10 transformed Y-axis. Values below [mean - 4 * SD] and above [mean + 4 * SD] were replaced with these cut-offs. Plots are based on uncorrected data. (a) Correlation between plasma and CSF concentrations of L-Valine in healthy volunteers. (b) Correlation between plasma and CSF concentrations of L-Phenylalanine in healthy controls. (c) Correlation between plasma ratio of L-Valine/L-Phenylalanine and CSF ratio of L-Valine/L-Phenylalanine in healthy controls. (d) Correlation between plasma and CSF concentrations of L-Valine in participants with migraine. (e) Correlation between plasma and CSF concentrations of L-Phenylalanine in participants with migraine. (f) Correlation between plasma ratio of L-Valine/ L-Phenylalanine and CSF ratio of L-Valine/L-Phenylalanine in participants with migraine. The dashed circle represents the 95% confidence interval of the Gaussian distribution. CSF = cerebrospinal fluid.
RkJQdWJsaXNoZXIy MTk4NDMw