FLZ treatment improves GI dysfunctions of the rotenone PD mouse model. (A) and (B) Intestinal transit distance in Weeks 3–4 (A) and Week 6 (B). (C)–(D) Colon length in Weeks 3–4 (C) and Week 6 (D). (E)–(F) Water percentage in fecal pellets in Weeks 1–4 (E) and Weeks 5–6 (F). (G)–(H) Numbers of total fecal pellets in Weeks 1–4 (G) and Weeks 5–6 (H). (I)–(L) Time course of fecal output over 20 min in Weeks 3–6. In (A)–(D), n = 5 replicates in each group. For GI function tests in Weeks 1–4, n = 15 for the Control group; n = 30 for the Model group. For GI function tests in Weeks 5–6, n = 15 for each group. Data are presented as mean ± SD. #P < 0.05, ##P < 0.01, ###P < 0.001 versus the Control group; ∗P < 0.05, ∗∗P < 0.01, ∗∗∗P < 0.001 versus the Rotenone group.