Fig. 1: Neuroprotective effects of Withaferin A in MPTP-induced PD mouse model.

A Diagram of the experimental design. MPTP (20 mg/kg) or vehicle (saline) was injected (i.p.) for 5 consecutive days starting on day -4 after acclimation (3 days), then mice intraperitoneally (i.p.) received WA (20 μg/kg) or vehicle (DMSO) per day for 7 days, tissues were harvested for molecular analyses at day 8 after the last behavior test. B Representative photomicrographs of TH and Nissl staining in SNc. Scale bars, 400 μm for low-magnification images and 40 μm for high-magnification images, respectively. C Unbiased stereological counts of TH-positive and Nissl-positive neurons in SNc. Data are mean ± s.e.m.; n = 30 biologically independent animals; *P = 0.0425 **P = 0.007, ***P < 0.001 by one-way ANOVA with Bonferroni’s post hoc test. D Representative immunoblots of TH, DAT, and β-actin in SNc (cropped blot images are shown, see Supplementary Fig. 16 for full immunoblots). E Quantification of TH and DAT protein levels in SNc. Data are mean ± s.e.m.; n = 9 biologically independent animals. *P < 0.05, **P < 0.01, and ***P < 0.001. F HPLC assessment of dopamine concentrations in striatum of vehicle (saline) or MPTP injected mice treated with vehicle or WA. Data are mean ± s.e.m.; n = 6 biologically independent animals; *P < 0.05, **P < 0.01, and ***P < 0.001 by one-way ANOVA with Bonferroni’s post hoc test. G Representative photomicrographs of TH staining in striatum, scale bar, 2 mm (upper panel) and 400 μm (down panel). H Quantification of TH-positive striatal fiber density. Data are mean ± s.e.m.; n = 9 biologically independent animals. I Time to traverse beam apparatus, time to descend pole, Hind-limb clasping reflex score, fall latency from an accelerating rotarod and gait analysis. Data are mean ± s.e.m.; n = 9 biologically independent animals. The one-way ANOVAs were used for statistical analysis followed by Bonferroni’s post hoc test. *P < 0.05, **P < 0.01, and ***P < 0.001. ns, not significant.