Figure 2.

HCT1026 inhibits MPTP-induced loss of striatal TH and DAT mRNAs expression. Ageing (9-11 month-old) C57Bl/6 mice fed with a control (ct) or HCT1026 diets (30 mg kg^-1) starting at -10 d, underwent an MPTP treatment according to the subchronic injection paradigm, as described. Age-matched mice fed with the different diets received physiologic saline and served as controls. Mice were sacrificed at different time-intervals after MPTP. Striatal tissue samples were processed for semi-quantitative RT-PCR analysis as described. Total RNA isolated and cDNA synthesized using Retroscript Kit (see Materials and Methods) following the manufacturer's directions. The 250 ng of cDNA were used for PCR, by using Super Taq DNA polymerase with specific primer pairs for TH (620 bp) and DAT (328 bp), and Classic S18 Standard (495 bp). Samples from PCR reactions were separated electrophoretically on 2% agarose gel containing 0,2 μg/ml of ethidium bromide (B-D, F-H). Fluorescent bands of amplified gene products were captured by using Gel Logic 200 Imaging System (Kodak), values normalized against S18 and ratios expressed as percent of control, within each experimental group (A, E). Differences were analyzed by ANOVA followed by Newman-Keuls test, and considered significant when p < 0.05. ** vs saline; ° p < 0.05 vs MPTP + control diet. Note the marked and long-lasting downregulation of TH (A,B,C,D) and DAT (E,F,G,H) mRNA transcript levels in striatal samples from ageing mice submitted to the subchronic MPTP regimen and the significant counteraction afforded by HCT1026.