Whole-brain slide-scanning of G2019S LRRK2 knockin mice under a specialized diet

G2019S LRRK2 knockin mice and their wild-type littermates were maintained on a normal chow diet (23.7% kcal from fat) for the first 11 months of life. At that time, animals were randomly assigned to either a high-fat diet group (60% kcal from fat) or a control diet group (10% kcal from fat). Mice remained on their respective diets for an additional five months. At 16 months of age, mice were anesthetized. Brains were collected and subsequently fixed for another 24 h in 4% PFA at 4 °C, followed by cryopreservation in 30% sucrose in 0.1 M PB for ≥ 24 h. Whole brains were subsequently processed using a microtome (Leica) into 35 μm-thick coronal sections, and serial sections of the whole brain were collected and used for subsequent staining. Every 4th serial brain section from each animal was pooled into a well for TH immunostaining (N300-109; Novus Biologicals), while every 8th serial section was pooled for Iba1 (019-19741; FUJIFILM Wako) and GFAP (G3893; MilliporeSigma) immunostaining.