Fig. 3. DACA alleviates motor dysfunction and protects dopamine
neurons in mice. (A) Schematic representation of the protocol used for
MPTP and DACA treatments. (B-C) Behavior test analysis. Open filed test
and pole test were recorded and analyzed (n =12 per group). (D-E)
Immunofluorescence analysis of dopamine neurons in brain SN tissue.
Scale bar 100 mm. Data are shown as representative pictures(D) and mean
fluorescence intensity(E) (n = 5 per group). (F-G) Immunofluorescence
analysis of dopamine neurons in striatum tissue. Scale bar 1000 mm. Data
are shown as representative pictures(F) and mean fluorescence
intensity(G) (n = 5 per group). (H-I) Immunoblot analysis of tyrosine
hydroxylase (TH) in midbrain tissue. Data are shown as representative
pictures (H) and quantified relative expression (I) (n = 5 per group).
(J-K) Immunoblot analysis of tyrosine hydroxylase (TH) in striatum
tissue. Data are shown as representative pictures (J) and quantified
relative expression (K) (n = 5 per group). Data shown are mean ± SEM;#p < 0.05, ##p
< 0.01 vs. control; *p < 0.05, **p < 0.01
vs. MPP+. NS. not significant.
3.3 DACA protected
dopaminergic neurons by preserving the TH level in the substantia
nigra(SN) and striatum
The expression of tyrosine hydroxylase (TH), a critical regulator
involved in the maintenance and regulation of midbrain neurons, is found
to be reduced in patients with PD. Immunofluorescence and Western blot
were used to detect the changes of TH levels in the brain of mice to
explore the therapeutic effect of DACA. Immunofluorescence labeling of
TH showed that MPTP provokes a marked degeneration of dopaminergic
neurons in the SNc and dopaminergic fibers in the Str, which was largely
prevented by DACA (Fig. 3D-G). Meanwhile, western blot analysis revealed
that DACA significantly attenuate the MPTP-induced decrease of TH levels
in the midbrain and striatum (Fig. 3H-K). These results suggest that
DACA protects against MPTP-triggered dopamine neurodegeneration in the
SN and striatum.