Berberine sensitizes neurons to glutamate toxicity.

Pretreating CGN 18 hours with 300 nM BBR exacerbates glutamate excitotoxicity. (A) Representative IF images for CGN pretreated with 300 nM BBR for 18 hours before the addition of 20 or 50 µM glutamate for 6 hours. (B) Quantification of CGN cell viabilities shown in A. (C) LDH release assay from the conditioned media for the described treatments shows exacerbation of toxicity by 300 nM BBR with glutamate co-treatments. For A, green is β-tubulin III, blue is Hoechst; the scale bar represents 100 µm. For panels B, n = 3 and panel C, n = 4. For B and C, *  = p<0.05, ***  = p<0.001.