Journal: Frontiers in Pharmacology

Article Title: c-Abl Inhibition Exerts Symptomatic Antiparkinsonian Effects Through a Striatal Postsynaptic Mechanism

doi: 10.3389/fphar.2018.01311

Figure Lengend Snippet: Effects of imatinib and levodopa on striatal motor behaviors and c-Abl/Cdk5/DARPP-32 signaling cascades. (A) Striatal penetration of intraperitoneally injected imatinib in mice. HPLC analysis were done to quantify concentrations of imatinib in the striatum ( n = 4), cortex ( n = 5), hippocampus ( n = 4), thalamus ( n = 4), and blood plasma ( n = 5) of naïve mice that received single i.p. injections of imatinib mesylate (25 mg/kg) 30 min before sacrifice. Values are expressed as means ± SEM. (B) Symptomatic antiparkinsonian effects of imatinib and levodopa in MPTP-treated mice. Behavioral tests were carried out in vehicle or MPTP-treated mice 30 min after a single i.p. injection of imatinib and/or levodopa. ( left-upper panel ) The beam-walking test for examining the effects of administration of imatinib mesylate (25 mg/kg) or levodopa (15 mg/kg). Values are means ± SEM ( n = 5–21). ∗ P < 0.05 versus vehicle-treated mice; one-way ANOVA [ F (5,77) = 11.265] followed by the Scheffe post hoc test. ( right-upper panel ) The rota-rod test for examining the effects of imatinib mesylate (25 mg/kg) or levodopa (15 mg/kg) administration. Values are means ± SEM ( n = 8–21). ∗ P < 0.05 versus vehicle-treated mice; one-way ANOVA [ F (5,80) = 7.710] followed by the Scheffe post hoc test. ( left-lower panel ) The beam-walking test for examining the effects of imatinib mesylate (10 mg/kg) and/or levodopa (2.5 or 5 mg/kg) administration. Values are means ± SEM ( n = 10–11). # P < 0.05 versus MPTP-treated mice; one-way ANOVA [ F (5,55) = 4.177] followed by the Scheffe post hoc test. ( right-lower panel ) The rota-rod test for examining the effects of imatinib mesylate (10 mg/kg) and/or levodopa (2.5 or 5 mg/kg) administration. Values are means ± SEM ( n = 10–11). ### P < 0.001 versus MPTP-treated mice; one-way ANOVA [ F (5,55) = 8.283] followed by the Scheffe post hoc test. (C) Western-blot analysis of striatal levels of Cdk5-pTyr15 and Cdk5 in vehicle or MPTP-treated mice 30 min after single i.p. injections of imatinib. Values are means ± SEM ( n = 4–5). ∗ P < 0.05 versus vehicle-treated mice, # P < 0.05 versus MPTP-treated mice; one-way ANOVA [ F Cdk5-pTyr15(4,19) = 50.391, F Cdk5(4,19) = 1.413] followed by the Scheffe post hoc test. IMB (10), imatinib mesylate (10 mg/kg); IMB (25), imatinib mesylate (25 mg/kg). (D) Western-blot analysis of striatal levels of DARPP-32-pThr75, DARPP-32-pThr34, and DARPP-32 in vehicle or MPTP-treated mice 30 min after a single i.p. injection of imatinib. Values are means ± SEM ( n = 4–5). ∗ P < 0.05 versus vehicle-treated mice, # P < 0.05 versus MPTP-treated mice; one-way ANOVA [ F DARPP-32-pThr75(4,19) = 35.089, F DARPP-32-pThr34(4,19) = 0.711, F DARPP-32(4,19) = 0.293] followed by the Scheffe post hoc test. IMB (10), imatinib mesylate (10 mg/kg); IMB (25), imatinib mesylate (25 mg/kg). (E) Western-blot analysis of striatal levels of Cdk5-pTyr15 and Cdk5 in MPTP-treated mice 30 min after a single i.p. injection of levodopa and/or imatinib. Values are expressed as means ± SEM ( n = 5–10). # P < 0.05, ## P < 0.01 versus MPTP-treated mice. One-way ANOVA [ F Cdk5-pTyr15(3,31) = 6.039, F Cdk5(3,17) = 0.258] followed by the Scheffe post hoc test. Levodopa (5), levodopa (5 mg/kg); IMB (10), imatinib mesylate (10 mg/kg). (F) Western-blot analysis of striatal levels of DARPP-32-pThr75, DARPP-32-pThr34, and DARPP-32 in MPTP-treated mice 30 min after a single i.p. injection of imatinib and/or levodopa. Values are expressed as means ± SEM ( n = 4-10). # P < 0.05, ## P < 0.01 versus MPTP-treated mice. One-way ANOVA [ F DARPP-32-pThr75(3,29) = 5.529, F DARPP-32-pThr34(3,16) = 1.257, F DARPP-32(3,16) = 2.886] followed by the Scheffe post hoc test. Levodopa (5), levodopa (5 mg/kg); IMB (10), imatinib mesylate (10 mg/kg). (G) Western-blot analysis of striatal levels of c-Abl-pTyr412, and c-Abl in MPTP-treated mice 30 min after a single i.p. injection of imatinib and/or levodopa. Values are expressed as means ± SEM ( n = 8–11). # P < 0.05 versus MPTP-treated mice; One-way ANOVA [ F c-Abl-pTyr412(3,34) = 5.820, F c-Abl(3,29) = 0.240] followed by Scheffe post hoc test. Levodopa (5), levodopa (5 mg/kg); IMB (10), imatinib mesylate (10 mg/kg).

Article Snippet: Antibodies against tyrosine hydroxylase (TH, 1:1000; Millipore, Billerica, MA, United States), dopamine transporter (DAT, 1:1,000; Chemicon International, Temecula, CA, United States), vesicle monoamine transporter 2 (VMAT2, 1:500, Santa Cruz Biotechnology, Santa Cruz, CA, United States), Cdk5-pTyr15 (1:1,000; Santa Cruz Biotechnology, Santa Cruz, CA, United States), Cdk5 (1:1,000; Cell Signaling, Danvers, MA, United States), DARPP-32-pThr75 (1:1,000; Cell Signaling), DARPP-32-pThr34 (1:1,000; Cell Signaling), DARPP-32 (1:1,000; Cell Signaling), c-Abl (1:1,000; Cell Signaling), and c-Abl-pTyr412 (1:1,000; Cell Signaling) were used.

Techniques: Injection, Western Blot