Journal: Translational Psychiatry

Article Title: Enhancing dopaminergic signaling and histone acetylation promotes long-term rescue of deficient fear extinction

doi: 10.1038/tp.2016.231

Figure Lengend Snippet: Rescue of impaired fear extinction induces a select transcriptional response in the medial prefrontal cortex (mPFC) and amygdala. ( a ) Scheme illustrating experimental paradigm. Mice were subjected to ‘normal' 0.6 mA fear conditioning (Cond.) in context A and fear extinction (Ext training in context B). All groups were conditioned on control diet (Ctl) before mice were subjected to dietary zinc restriction (ZnR) for 14 days till Ext. ( b ) Heatmap depicting differentially expressed genes in the mPFC (491) and amygdala (52) determined using microarray analysis between non-extinguishing Ctl diet-fed mice and extinguishing ZnR-fed mice. Each line depicts a differentially regulated gene; each row depicts the gene expression in each animal. Blue and red indicate low and high levels of expression, respectively. ( c ) Histogram showing the biological process to which the differentially regulated genes belong (orange, number of differentially regulated genes per biological process; green, significance of enrichment).

Article Snippet: mPFC and amygdala tissue punches were formaldehyde crosslinked and chromatin immunoprecipitation was performed following a modification of the Active Motif ChIP-IT Express kit protocol with an ac H4 antibody.

Techniques: Control, Microarray, Gene Expression, Expressing

Journal: Translational Psychiatry

Article Title: Enhancing dopaminergic signaling and histone acetylation promotes long-term rescue of deficient fear extinction

doi: 10.1038/tp.2016.231

Figure Lengend Snippet: Rescue of impaired fear extinction enhances expression of genes coding for dopamine D1 (Drd1a) and D2 (Drd2) receptors. ( a ) Scheme illustrating experimental paradigm for b , c . Cond, ‘normal' 0.6 mA fear conditioning; Ext, extinction training; Exp, fear expression; Ctl, control diet; ZnR, dietary zinc restriction. Expression of dopaminergic genes in the medial prefrontal cortex (mPFC) and amygdala following successful rescue of impaired fear extinction ( b ) and following fear expression ( c ). * P <0.05 Ctl versus ZnR, ** P <0.01 Ctl versus ZnR. n =3–8 per group. ( d ) Scheme illustrating experimental paradigm for e . Cond., ‘normal' (0.6 mA) conditioning; ER, extinction retrieval; SR, spontaneous recovery; RN, fear renewal. ( e ) Lower freezing was observed in L-dopa-treated mice when compared with VEH-treated during Ext. trial blocks 7–8 through to 15–16 and also during ER. n =10 per group. * P <0.05 post hoc testing L-dopa versus VEH. ( f ) Scheme illustrating experimental paradigm for g . Cond., ‘weak' (0.3 mA) conditioning. ( g ) Lower freezing was observed in L-dopa-treated mice when compared with VEH-treated mice during ER. n =7–8 per group. * P <0.05 post hoc testing L-dopa versus VEH.

Article Snippet: mPFC and amygdala tissue punches were formaldehyde crosslinked and chromatin immunoprecipitation was performed following a modification of the Active Motif ChIP-IT Express kit protocol with an ac H4 antibody.

Techniques: Expressing, Control

Journal: Translational Psychiatry

Article Title: Enhancing dopaminergic signaling and histone acetylation promotes long-term rescue of deficient fear extinction

doi: 10.1038/tp.2016.231

Figure Lengend Snippet: Enhancing histone acetylation promotes enduring and context-independent rescue of newly formed extinction memories. ( a ) Scheme illustrating experimental paradigm for b , c . Cond., ‘normal' fear conditioning; Exp, fear extinction; Exp, fear expression; Ctl, control diet; ZnR, zinc-restricted diet. n =3–8 per group. ( b ) Enhanced abundance of acH4 was observed in the promoter region of Drd2 following fear extinction in the medial prefrontal cortex (mPFC). ( c ) No changes in any group were observed following fear expression. ( d ) Scheme illustrating experimental paradigm for e – p . ER, extinction retrieval; SR, spontaneous recovery; RN, renewal. ( e ) Freezing was lower in MS-275 administered mice during ER, SR and RN. n =9–10 per group. * P <0.05 post hoc testing MS-275 versus VEH. ( f ) Representative epifluorescent photomicrograph of a coronal section (Bregma +1.78 mm) stained for acH4 immunoreactivity. IL, infralimbic cortex; PL, prelimbic cortex. Scale bar=500 μm. ( g ) Representative epifluorescent photomicrographs delineating the cortical layers within the IL. Scale bar=100 μm. ( h , i ) Enhanced acH4 epifluorescence was observed in NeuN-positive (NeuN+) cell populations following MS-275 administration and following successful fear extinction (CS+) in layer II and in layer III, but not layer V/VI, compared with vehicle-treated counterparts (VEH). ** P <0.01 post hoc testing MS-275 versus VEH in conditioned (CS+) groups. n =4–6/group. Scale bar=20 μm. ( j ) Representative epifluorescent photomicrograph of a coronal section (Bregma −1.56 mm) delineating the basal amygdala region quantified. BA, basal amygdala; Ce, central amygdala; LA, lateral amygdala. Scale bar=250 μm. ( k , l ) Enhanced acH4 epifluorescence was observed in NeuN-positive nuclei (NeuN+) only successful fear extinction acquisition and MS-275 administration. Scale bar=20 μm. ** P <0.01 post hoc testing MS-275 versus VEH in conditioned (CS+) groups. n =4–6/group. ( m ) Representative epifluorescent photomicrograph of a coronal section (Bregma +1.78 mm) stained for acH4 immunoreactivity. IL, infralimbic cortex; PL, prelimbic cortex. Scale bar=500 μm. ( n ) Representative epifluorescent photomicrographs delineating the cortical layers within the PL. Scale bar=100 μm. ( o , p ) Enhanced acH4 epifluorescence was observed in NeuN-positive (NeuN+) cell populations following successful fear extinction (CS+) in mice administered VEH and MS-275 to a similar level in layer II, but not layers II or V/VI, compared to vehicle-treated counterparts (VEH). Scale bar=20 μm. * P <0.05, ** P <0.01 post hoc testing MS-275 versus VEH in conditioned (CS+) groups. n =4–6 per group.

Article Snippet: mPFC and amygdala tissue punches were formaldehyde crosslinked and chromatin immunoprecipitation was performed following a modification of the Active Motif ChIP-IT Express kit protocol with an ac H4 antibody.

Techniques: Expressing, Control, Staining

Journal: PLOS ONE

Article Title: Voluntary wheel running exercise rescues behaviorally-evoked acetylcholine efflux in the medial prefrontal cortex and epigenetic changes in ChAT genes following adolescent intermittent ethanol exposure

doi: 10.1371/journal.pone.0311405

Figure Lengend Snippet: Subjects received intragastric gavages of either EtOH (5g/kg) or tap water on a two-day-on two-day-off schedule from PD 25–54. Blood ethanol content in AIE animals was measured 1h following the eighth gavage. At PD ~60, subjects were implanted with a guide cannula into the mPFC and were subsequently assigned to either cages with free access to a running wheel (VEx) or a standard cage (Stat) from PD 75–105. At PD ~115, subjects were run on a spontaneous alternation task with concurrent in vivo microdialysis to measure behaviorally evoked ACh efflux. Following the conclusion of microdialysis for all subjects, they were run on an operant attention set shifting task to measure cognitive and behavioral flexibility (A) . Growth Curve for AIE (Male = 25, Female = 26) and control (Male = 22, Female = 34) rats during gavage. Weights increased over time, while males weighed more than females across all time points and gained weight at faster rate (B). Blood ethanol content for male (n = 25) and female (n = 26) AIE subjects. All subjects reached the criteria for binge levels of intoxication (80mg/dL) and BEC did not differ as a function of sex (C). Total wheel running distances among VEx animals (each data point is one cage) (D). There was a main effect of Sex: Females ran significantly more than males.

Article Snippet: To assess the ACh concentration of the microdialysis samples in the mPFC, high-performance liquid chromatography (HPLC) with electrochemical detection (Amuza, San Diego, CA, USA) was used.

Techniques: In Vivo, Control

Journal: PLOS ONE

Article Title: Voluntary wheel running exercise rescues behaviorally-evoked acetylcholine efflux in the medial prefrontal cortex and epigenetic changes in ChAT genes following adolescent intermittent ethanol exposure

doi: 10.1371/journal.pone.0311405

Figure Lengend Snippet: Schematic showing microdialysis setup, with guide cannulae implanted in the mPFC and neostigmine + aCSF infused to detect extracellular ACh efflux during four-arm spontaneous alternation maze exploration (A) . Cresyl violet staining showing typical cannula placement in the mPFC (B) . ACh efflux in the mPFC during spontaneous alternation (Males: Con-Stat = 11, Con-VEx = 7, AIE-Stat = 7, AIE-VEx = 9; Females: Con-Stat = 8, Con-VEx = 9, AIE-Stat = 9, AIE-VEx = 8) (C) . All animals showed significant rises in ACh during maze exploration compared to baseline, but this rise was blunted in AIE animals and was improved in exercise animals, irrespective of AIE treatment. Percent alternation score during spontaneous alternation (D) . Spontaneous alternation score did not differ as a function of AIE treatment or Exercise. Number of arm entries made during spontaneous alternation (Males: Con-Stat = 11, Con-VEx = 7, AIE-Stat = 7, AIE-VEx = 9; Females: Con-Stat = 8, Con-VEx = 8, AIE-Stat = 9, AIE-VEx = 7). Female rats made more arm entries than males irrespective of treatment group. Arm entries did not differ as a function of AIE, but VEx animals made less arm entries than stationary controls (E) . *p<0.05; **p<0.01. Exp = Main effect of Exposure; VEx = Main Effect of Voluntary Wheel Exercise; Sex = Main effect of Sex.

Article Snippet: To assess the ACh concentration of the microdialysis samples in the mPFC, high-performance liquid chromatography (HPLC) with electrochemical detection (Amuza, San Diego, CA, USA) was used.

Techniques: Staining