Figure 2.

N-2-MPG neutralizes 3-aminopropanal cytotoxicity by thioacetal formation. (A) Prevention of 3-aminopropanal-induced neuronal cytotoxicity by N-2-MPG. The glial cell line (HTB14) was exposed to 160 μM 3-aminopropanal and increasing concentrations of N-2-MPG as described in the legend to Table 1 and in Materials and Methods. Cell viability was determined after an overnight exposure by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. (B) Prevention of 3-aminopropanal (3-AP)-induced glial apoptosis by N-2-MPG. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining of the glial cell line HTB14 5 h after treatment with 3-aminopropanal (160 μM) or vehicle, and N-2-MPG (1 mM) or medium alone, as described in Materials and Methods. A Becton Dickinson FACScan was used for all analyses; 5,000–10,000 events (ungated) were collected by using a single-color histogram for FITC. (C) Electrospray ionization mass spectrum of water solutions of 3-aminopropanal (300 μM), (D) N-2-MPG (1 mM), and (E) both compounds mixed together (resulting in a thioacetal adduct formation). The arrows indicate the expected molecular ions.