Fig. 1. TSPAN5 and 5-HT concentrations can be regulated by EtOH and acamprosate.
a Tryptophan metabolic pathway in schematic outline. b TSPAN5 mRNA expression was down-regulated in iPSC-derived forebrain neurons (n = 5) after exposure to EtOH (25 mM) for 24 h. c 5-HT concentrations decreased significantly in iPSC-derived forebrain neuron culture medium in response to EtOH treatment. d Downregulation of TSPAN5 expression resulted from EtOH exposure, with downstream effects on the expression of a series of genes involved in 5-HT biosynthesis and metabolism. In parallel, knockdown of TSPAN5 (e) decreased 5-HT concentrations (f), and resulted in the downregulation of genes associated with 5-HT biosynthesis and metabolism (g). Similar results were obtained when the cells were exposed to acamprosate (5 μM) for 24 h. Specifically, TSPAN5 expression, 5-HT concentration and expression of the genes displayed in panels (c, d, f, and g) all were down-regulated in response to acamprosate treatment (h–j). Five independent human-derived-iPSC-derived neuron cell lines were used to perform these experiments. Cells were seeded in 6-well plates at a density of 2.5 ×105 cells per well in 2 ml culture medium. *A p value ≤ 0.05 was considered statistically significant (two tailed paired t test). Three independent experiments were performed. All values are mean ± SEM.