Table 2. Effects of antioxidants on the inhibitory effects of DZ and DZO on neurite outgrowth.

Treatment	Longest neurite length (μm)	Minor neurite length (μm)	No. neurites/cell
Control	140.3 ± 6.8	22.0 ± 0.7	4.7 ± 0.1
PBN	172.4 ± 15.4	13.5 ± 0.7#	5.0 ± 0.2
Mel	149.7 ± 15.5	21.0 ± 1.4	4.1 ± 0.2
DZ	64.8 ± 3.0#	15.5 ± 0.4#	4.6 ± 0.1
DZ + PBN	210.5 ± 20.4#	15.7 ± 0.9#	5.5 ± 0.4
DZ + Mel	175.3 ± 15.6	16.2 ± 0.8#	4.6 ± 0.2
DZO	51.8 ± 2.3#	15.6 ± 0.5#	4.6 ± 0.2
DZO + PBN	188.1 ± 21.8*	20.3 ± 1.1*	5.4 ± 0.3
DZO + Mel	138.2 ± 12.2	16.8 ± 1.2#	4.7 ± 0.2

Astrocytes were pre-treated with 200 μM melatonin (Mel) or 100 μM PBN for 3 h prior to washout and treatment with 10 μM DZ or DZO for 24 h. After further wash-out, astrocytes were co-cultured with hippocampal neurons for 48 h, as described in Methods. Results represent the mean (± SEM) of at least 60 cells per treatment group. Significantly different from untreated control,

^*, p<0.05;

^#, p<0.001.