Figure 12.

Effects of exendin-4 and DA-CH5 on 6-OHDA-induced desensitization of the insulin signaling pathway in the rat SN.

(A) Bands of proteins in the insulin signaling pathway in SN lysates, as detected by western blot assay. GAPDH was used as the loading control. (B–D) Quantification of p-IRS-1 (B), PGC-1α (C), and NRF-1 (D) expression in the SN. Data are represented as the mean ± SD of four rats per group. ‡‡‡P < 0.001, vs. sham group; $P < 0.05, $$P < 0.01, $$$P < 0.001, vs. 6-OHDA group (one-way analysis of variance followed by Tukey’s multiple comparison test). 6-OHDA: 6-Hydroxydopamine; exendin-4 and DA-CH5: glucagon-like peptide-1/glucose-dependent insulinotropic polypeptide dual receptor agonist; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; IRS-1: insulin receptor substrate-1; NRF-1: nuclear respiratory factor 1; PD: Parkinson’s disease; PGC-1α: proliferator-activated receptor-gamma coactivator 1α; SN: substantia nigra.