Fig. 1.

Minocycline prevents PARP-1-mediated neuronal death. (A) Photomicrographs of neuronal cultures, 24 h after 30-min incubations with MNNG (75 μM) alone or in combination with minocycline (Mino, 100 nM) or the established PARP inhibitors DPQ (25 μM) or PJ34 (100 nM). Control wells received medium exchanges only. Live cells are phase-bright with well demarcated cell bodies. (Scale bar, 20 μm.) (B) Dose–response curves of Mc, DPQ, and PJ34 on MNNG-induced neuronal death. (C) Dose–response curves of Mc, DPQ, and PJ34 on SIN-1-induced neuronal death. Neurons were incubated with 2 mM SIN-1 for 60 min. (D) The neuroprotective effects of minocycline (Mc, 100 nM) are not additive with DPQ (25 μM). ∗∗, P < 0.01 vs. all other conditions; P > 0.1 for comparisons between the DPQ plus Mc condition vs. DPQ alone or vs. Mc alone. Data in B–D are means ± SEM of three independent experiments, each performed in triplicate.