Figure A1.

Effect of glucose and oxygen on mRNA expression of serotonin-regulating genes in ACH-3P cells. Cells were cultured in the absence (control, grey bars) or presence of 25 mM D-glucose (hyperglycemia, red bars) at 6.5% O₂ or 2.5% O₂ for 24 h or 72 h. Relative mRNA expression levels of (a) SERT, (b) TPH1 and (c) MAOA were determined by RT-qPCR and normalized to YWHAZ mRNA level. Results of three independent experiments, each done in triplicate, are shown. For each gene, data at each time point are presented relative to the mean of the control samples at 6.5% O₂, which was arbitrarily set to 1.0; bars represent mean ± SEM. Statistical analysis used ANCOVA with cell passage as covariate and Sidak’s post hoc test to adjust for multiple comparisons. * p < 0.05, ** p < 0.01, *** p < 0.001, **** p < 0.0001, red dashed line—main effect of glucose, gray line—main effect of oxygen. ^# proportion of total variance after controlling for the effect of the cell passage (partial η²).