Up-Regulation of <i>m/z</i> = 3,959 VGF23–62 Peptide Peak in CSF from First-Onset, Drug-Naïve Schizophrenia Patients

<p>Forty healthy volunteers and 41 untreated paranoid schizophrenia CSF samples were included in this study. A clear up-regulation of the peak at 3,959 Da was observed (as shown in [A], with five representative spectra from each group). <a href="http://www.plosmedicine.org/article/info:doi/10.1371/journal.pmed.0030428#pmed-0030428-g002" target="_blank">Figure 2</a>B reveals the relative intensity of a 3,959-Da peak in healthy volunteers and first-onset, drug-naïve schizophrenia patients. <a href="http://www.plosmedicine.org/article/info:doi/10.1371/journal.pmed.0030428#pmed-0030428-g002" target="_blank">Figure 2</a>C shows a Western blot analysis of VGF protein in the prefrontal cortex of age-matched controls and patients with schizophrenia. Eight schizophrenia and eight control brains (prefrontal cortex, age matched) were randomly selected, and Western analysis was performed using a polyclonal antibody against the C-terminal region of the VGF protein. VGF was found up-regulated in four patients with schizophrenia (out of eight patients), while no signal was detected in the control patients. This experiment was repeated twice on the same samples under identical conditions, except that a different batch antibody from the same company was used. Similar results were obtained. For demographic details, see <a href="http://www.plosmedicine.org/article/info:doi/10.1371/journal.pmed.0030428#pmed-0030428-t004" target="_blank">Table 4</a>.