ppm plx5622  (MedChemExpress)

Journal: Brain

Article Title: A cell autonomous regulator of neuronal excitability modulates tau in Alzheimer’s disease vulnerable neurons

doi: 10.1093/brain/awae051

Figure Lengend Snippet: Effect of Dek silencing in ECII neurons of hMAPT mouse . ( A ) Confocal microscopy images of immunofluorescence staining of transduced neurons (mCherry, magenta), ECII neurons (Reelin, cyan) and microglia (Iba1, yellow) at 4 days, 1 week and 2 weeks post-transduction of human-tau transgenic (hMAPT) mice. Scale bar = 100 μm. The graphs show the quantifications of the number of reelin positive cells and of Iba1 fluorescence intensity in layer II of the mouse entorhinal cortex (EC) in the control (CONT) and Dek -silenced hemispheres. Two-way ANOVA Sidak’s multiple comparisons test P -value < 0.0001 (Reelin, 2 weeks), P = 0.044 (Iba1, 4 days), P = 0.021 (Iba1, 2 weeks) ( n = 4–6 sections per time point per group from two different animals). ( B ) Confocal microscopy images of immunofluorescence staining of transduced neurons (mCherry, magenta), ECII neurons (Reelin, cyan) and phospho-tau Thr231 (AT180, yellow) at 2 weeks post-transduction of control or sh Dek -carrying AAVs in PLX5622 diet fed hMAPT mice. Scale bar = 100 μm. The graph shows the quantification of AT180 fluorescence intensity, paired by the control and the Dek -silenced opposite hemisphere for each hMAPT mouse. Two-way ANOVA Sidak’s multiple comparisons test P -value = 0.0014 ( n = 8 mice per group). sh = small hairpin.

Article Snippet: Chow containing PLX5622 at 1200 ppm was manufactured by a trained diet preparation operator at Research Diets Inc in AIN-76A rodent diet.

Techniques: Confocal Microscopy, Immunofluorescence, Staining, Transduction, Transgenic Assay, Fluorescence, Control

Journal: Aging Cell

Article Title: Exercise rejuvenates microglia and reverses T cell accumulation in the aged female mouse brain

doi: 10.1111/acel.14172

Figure Lengend Snippet: Benefits of exercise on cognitive abilities of aged mice remain with microglial depletion. (a) Overview of experimental timeline. Young adult (3‐month‐old) and aged (18‐month‐old) mice underwent active place avoidance (APA) testing over a course of 5 days (APA1). Aged mice were then placed on PLX5622‐containing chow (to deplete microglia), or control chow and re‐tested for acquisition of a new APA task (APA2) 21 days later. (b) Diagram of the visual cues used during APA testing prior to (APA1) and after (APA2) PLX5622 (or control chow) administration. The maroon triangle indicates the shock zone location. Note that different visual cues were used in APA2 versus APA1 to assess spatial learning (as opposed to task recall). (c) Shock zone entries during APA1 testing (10‐min trials/day). Aged mice had significantly more entries on day 5 compared to young adult mice (198% increase, t (115) = 2.79, p = 0.031, n = 12–13). (d) Percentage improvement in APA1 performance of individual mice ( t = 2.50, df = 23, p = 0.012; minimum, 25% percentile, median, 75% percentile, maximum, Young SED: −16.67, 59.70, 86.34, 91.96, 100.00; Aged SED: −60.00, 24.16, 45.45, 51.67, 78.95, 138.90). (e) Schematic overview showing the split of aged sedentary mice used in APA1 into two groups, receiving either control chow (yellow), or PLX5622‐containing chow (to deplete microglia, pink). (f) Confocal images of IBA1 immunostaining showing effective depletion of microglia in the hippocampus of aged (18‐month‐old) mice that were fed PLX5622 (PLX) or control (CON) chow. Scale bar: 50 μm. (g) Entries into the shock zone during APA2 (10‐min trial/day) for aged mice given either control of PLX5622 chow (F[1,9] = 0.075, p = 0.79). (h) Percentage improvement in APA2 testing for aged mice with and without microglia ( t = 0.31, df = 10, p = 0.77; minimum, 25% percentile, median, 75% percentile, maximum, Aged SED/control chow: −57.14, −33.83, 26.67, 70.38, 78.26; Aged SED/PLX5622: −169.20, −25.00, 11.11, 73.33, 83.33). (i) Overview of experimental layout and timeline. Aged (18‐month‐old) mice received either control or PLX5622‐containing chow (to deplete microglia) for 61 days. Mice were allowed to run for 21 days, allowed a 2‐week rest period, and then tested in APA 14 days after completion of the exercise paradigm. (j) Distance travelled during the habituation trial of APA testing (shock zone off; minimum, 25% percentile, median, 75% percentile, maximum, Aged SED/control chow: 85.21, 92.01, 100.5, 106.40, 125.30; Aged RUN/control chow: 86.10, 92.72, 103.00, 109.20, 127.40; Aged RUN/PLX5622 run: 68.33, 82.44, 98.38, 111.0, 114.0). (k) Total number of entries into the shock zone during APA testing (20‐min trial/day; F(2,44) = 3.81, p = 0.0297). (l) Percentage improvement in APA performance for individual mice, assessed by the change in entries on testing day 5 versus day 1 for individual mice (F[2,44] = 8.64, p = 0.0007; minimum, 25% percentile, median, 75% percentile, maximum, Aged SED/control chow: 38.46, −20.83, 0, 18.75, 50.0; Aged RUN/control chow: −44.44, 18.63, 39.57, 59.24, 86.96; Aged RUN/PLX5622: 7.69, 22.70, 47.70, 58.17, 96.30). (m) Schematic of experimental timeline, as detailed above, used to examine neuroplasticity and neurogenic effects of exercise. Aged (18‐month‐old) mice received either control or PLX5622‐containing chow (to deplete microglia) for 56 days. Mice were allowed 14 days of rest after 21 days of voluntary wheel running to allow newborn cells to differentiate into DCX pos immature neurons. (n) Exercise (RUN) increased the number of synaptophysin (SYN) puncta in the hippocampus of 18‐month‐old mice compared to sedentary (SED) aged‐matched controls (F(2,12) = 12.88, p = 0.0010). PLX5622 did not significantly alter the increase in SYN observed in Aged RUN mice (Aged SED/Control chow vs Aged RUN/PLX5622, p > 0.99; n = 5/group; minimum, 25% percentile, median, 75% percentile, maximum: Aged SED/Control chow: 0.0016, 0.0018, 0.0496, 0.058, 0.065; Aged RUN/Control chow, 0.079, 0.086, 0.106, 0.110, 0.112; Aged RUN/PLX5622: 0.061, 0.073, 0.087, 0.105, 0.112). (o) Representative confocal images for synaptophysin (SYN) staining in the hippocampus of Aged SED/Control chow, Aged Run/Control chow and Aged RUN/PLX5622 mice. Scale bar = 50 μm. (p) Exercise (RUN) increased the number of immature DCX pos neurons in 18‐month‐old mice treated with a control diet compared to sedentary age‐matched controls (SED; 2.64‐fold increase, t (26) = 2.84, p = 0.017, n = 8–11). PLX5622 significantly decreased the number of DCX pos immature neurons in mice that underwent exercise (2.50‐fold decrease, t (26) = 2.81, p = 0.019, n = 6–11; minimum, 25% percentile, median, 75% percentile, maximum, Aged SED/control chow: 1.69 2.43, 3.07, 3.44, 4.05; Aged RUN/control chow, 2.25, 3.68, 6.23, 9.71, 19.69; Aged RUN/PLX5622: 0.57, 1.72, 3.16, 4.74, 5.13). (q) Representative confocal images of immature DCX pos neurons in hippocampus of aged mice fed either control or PLX5622‐containing chow. Scale bar = 50 μm. Note the exercise‐induced increase in DCX pos cells in the RUN condition, and the absence of this when microglia were depleted (PLX5622). Data are represented as mean ± SEM unless specified otherwise. Statistics: unpaired Student's t ‐test (d, h), repeated two‐way ANOVA (c, g, k), or one‐way ANOVA (j, l, n, p) both followed by Bonferroni post‐hoc comparison with Geisser–Greenhouse correction. * p < 0.05, ** p < 0.01, *** p < 0.001. Data points represent individual mice.

Article Snippet: To deplete microglia, mice were provided ad libitum with chow containing 1200 ppm PLX5622 (Plexxikon, USA; used under the permission of a material transfer agreement).

Techniques: Control, Immunostaining, Staining, Comparison