<i>Fkbp5</i> DNA methylation decreases with age in mice.

<p>Isolated DNA samples from wild-type mice aged 1 (n = 3), 3.5 (n = 3), 4 (n = 6), 5 (n = 7), 6 (n = 6), and 12 (n = 3) months were subjected to bisulfite pyrosequencing. Multiple CpG sites in intron 5 were analyzed for <i>Fkbp5</i> methylation. Significant demethylation was found at CPG_3 (r = −0.3890, p<0.05), CPG_4 (r = −0.4004, p<0.05) and CpG_5 (r = −0.5044, p<0.01) as measured by linear regression analyses.</p

Blood composition and animal mass of wild-type versus FKBP5^−/− mice do not differ.

<p>WBC: white blood cells, RBC: red blood cells, Lym: lymphocytes, Mono: monocytes, Gran: granulocytes, HGB: hemoglobin, PLT: platelets. Wild-type, n = 11; FKBP5^−/−, n = 12. Values are listed as the mean ± the standard error of the mean.</p><p>Blood composition and animal mass of wild-type versus FKBP5^−/− mice do not differ.</p

FKBP51 does not affect longevity.

<p>No significant differences were found in the percent survival of wild-type (wt) and <i>FKBP5^−/−</i> mice, p>0.05. wt, n = 34 (18 male and 16 female); <i>FKBP5^−/−</i>, n = 32 (18 male and 14 female).</p

<i>FKBP5^−/−</i> mice display enhanced cognitive flexibility in the radial arm water maze.

<p>(A) No differences were found in acquisition learning between genotypes (p>0.05). (B) There was a main effect of genotype (p<0.05) during reversal training, indicating <i>FKBP5^−/−</i> mice made fewer errors across sessions. Data points represent a session of three trials. *p<0.05. wild-type (wt), n = 9; <i>FKBP5^−/−</i>, n = 10.</p

Deletion of <i>FKBP5</i> does not alter glucose metabolism.

<p><i>FKBP5^−/−</i> mice displayed normal glucose tolerance up to 120 minutes following glucose injection compared to wild-type (wt) mice, p>0.05. wt, n = 7; <i>FKBP5^−/−</i>, n = 10.</p

Ablation of <i>FKBP5</i> does not alter cytokine levels over time.

<p>Serum levels of interleukin-1β (A) and interleukin-5 (D) were decreased at 6 months (p<0.05 via t-test) but not across time (p>0.05 by two-way ANOVA). Levels of interleukin-2 (B), interleukin-4 (C), interleukin-10 (E), granulocyte-macrophage colony-stimulating factor (F), interferon gamma (G), or tumor necrosis factor alpha (H) did not differ between genotypes across lifespan, p>0.05. *p<0.05. wild-type (wt), n = 6 for each age; <i>FKBP5^−/−</i>, n = 7 at 7 and 10 months, n = 6 at 21 months.</p

Synthesis, Stereochemical Analysis, and Derivatization of Myricanol Provide New Probes That Promote Autophagic Tau Clearance

We previously discovered that one specific scalemic preparation of myricanol (<b>1</b>), a constituent of Myrica cerifera (bayberry/southern wax myrtle) root bark, could lower the levels of the microtubule-associated protein tau (MAPT). The significance is that tau accumulates in a number of neurodegenerative diseases, the most common being Alzheimer’s disease (AD). Herein, a new synthetic route to prepare myricanol using a suitable boronic acid pinacol ester intermediate is reported. An X-ray crystal structure of the isolated myricanol (<b>1</b>) was obtained and showed a co-crystal consisting of (+)-a<i>R</i>,11<i>S</i>-myricanol (<b>2</b>) and (−)-a<i>S</i>,11<i>R</i>-myricanol (<b>3</b>) coformers. Surprisingly, <b>3</b>, obtained from chiral separation from <b>1</b>, reduced tau levels in both cultured cells and <i>ex vivo</i> brain slices from a mouse model of tauopathy at reasonable mid-to-low micromolar potency, whereas <b>2</b> did not. SILAC proteomics and cell assays revealed that <b>3</b> promoted tau degradation through an autophagic mechanism, which was in contrast to that of other tau-lowering compounds previously identified by our group. During the course of structure–activity relationship (SAR) development, we prepared compound <b>13</b> by acid-catalyzed dehydration of <b>1</b>. <b>13</b> had undergone an unexpected structural rearrangement through the isomyricanol substitution pattern (e.g., <b>16</b>), as verified by X-ray structural analysis. Compound <b>13</b> displayed robust tau-lowering activity, and, importantly, its enantiomers reduced tau levels similarly. Therefore, the semisynthetic analogue <b>13</b> provides a foundation for further development as a tau-lowering agent without its SAR being based on chirality

Synthesis, Stereochemical Analysis, and Derivatization of Myricanol Provide New Probes That Promote Autophagic Tau Clearance

We previously discovered that one specific scalemic preparation of myricanol (<b>1</b>), a constituent of Myrica cerifera (bayberry/southern wax myrtle) root bark, could lower the levels of the microtubule-associated protein tau (MAPT). The significance is that tau accumulates in a number of neurodegenerative diseases, the most common being Alzheimer’s disease (AD). Herein, a new synthetic route to prepare myricanol using a suitable boronic acid pinacol ester intermediate is reported. An X-ray crystal structure of the isolated myricanol (<b>1</b>) was obtained and showed a co-crystal consisting of (+)-a<i>R</i>,11<i>S</i>-myricanol (<b>2</b>) and (−)-a<i>S</i>,11<i>R</i>-myricanol (<b>3</b>) coformers. Surprisingly, <b>3</b>, obtained from chiral separation from <b>1</b>, reduced tau levels in both cultured cells and <i>ex vivo</i> brain slices from a mouse model of tauopathy at reasonable mid-to-low micromolar potency, whereas <b>2</b> did not. SILAC proteomics and cell assays revealed that <b>3</b> promoted tau degradation through an autophagic mechanism, which was in contrast to that of other tau-lowering compounds previously identified by our group. During the course of structure–activity relationship (SAR) development, we prepared compound <b>13</b> by acid-catalyzed dehydration of <b>1</b>. <b>13</b> had undergone an unexpected structural rearrangement through the isomyricanol substitution pattern (e.g., <b>16</b>), as verified by X-ray structural analysis. Compound <b>13</b> displayed robust tau-lowering activity, and, importantly, its enantiomers reduced tau levels similarly. Therefore, the semisynthetic analogue <b>13</b> provides a foundation for further development as a tau-lowering agent without its SAR being based on chirality