Figure 3.

Neuroprotective effects of 3-HAA and 3-HK. Primary human mixed glial and neuronal cultures were stimulated with IL-1 or IL-1/IFN-γ with or without 3-HAA (100 μmol/L) for 72 hours to induce neurotoxicity, as described in Materials and Methods. Control cultures were not treated with cytokines. Culture medium was changed to low serum medium (0.5% FCS) 24 hours before cytokine treatment. A: Representative cultures examined with trypan blue exclusion test show induction of neuronal death with IL-1 or IL-1/IFN-γ (blue nuclei, arrows; cultures derived from two different cases are shown). The number of dead neurons is lower in 3-HAA–treated cultures. B: The effect of 3-HAA on cytokine- or PIC-induced neuronal death was determined in mixed cultures derived from several different brain cases, and the results show significant neuroprotection by 3-HAA in all three conditions (single-sample t-test). C: The effect of 3-HK on IL-1/IFN-γ–induced neurotoxicity was also determined. 3-HK dose dependently (100 μmol/L >10 μmol/L) inhibited neuronal death. 3-HK at 1 μmol/L had no effect (not shown). Data are presented as mean ± SD from quadruple values, and statistics were performed by analysis of variance with Bonferroni posttest (***P < 0.001). Shown is one of three experiments with similar results. D: The effect of 3-HAA on cell survival or death in control mixed cultures. No difference was noted by LDH measurements in culture supernatants collected at 72 hours. Data are OD values pooled from three different cases.