Fig. 2

Abnormal 5-HTergic systems and HTR1B signal pathway in the blood of schizophrenia. A-F The concentrations of HTR1B, SERT, TPH2, 5-HT, Arc, and ALKBH5 in the plasma of schizophrenia patients (n = 44) and controls (n = 37) by ELISA (p < 0.001 by median and nonparametric analysis). G The mRNA level of ERVWE1 in the whole peripheral blood of schizophrenia patients (n = 15) and healthy controls (n = 14) by RT-qPCR (p < 0.001 by median and nonparametric analysis). H Differences in ERVWE1 protein expression in schizophrenia patients (n = 44) and controls (n = 37) by ELISA (p < 0.001 by median and nonparametric analysis). I–N Correlation of ERVWE1 protein level with HTR1B (r = 0.81, p < 0.001, n = 44), Arc (r = 0.77, p < 0.001, n = 44), ALKBH5 (r = 0.78, p < 0.001, n = 44), 5-HT (r = – 0.57, p < 0.001, n = 44), SERT (r = – 0.41, p < 0.01, n = 44), and TPH2 (r = − 0.33, p = 0.03, n = 44) protein levels in the plasma of schizophrenia patients by Spearman. O–Q Correlation analysis of plasma HTR1B with plasma 5-HT (r =  − 0.6, p < 0.001, n = 44), Arc (r = 0.6, p < 0.001, n = 44), and ALKBH5 (r = 0.7, p < 0.001, n = 44) in schizophrenia by Spearman. Dots depict schizophrenia patients. Data are mean ± SD, but a few are overlapping and cannot be separated on the graph