Identification Of H3K9AC As An Epigenetic Marker In Gestational Choline-modified Depression-like Behavior And Sex-related Difference In Food-anticipatory Activity Of Mice

Here,we show that SUP epigenetically modifies mood of adult offspring in two generations though H3K9 acetylation(H3K9ac).SUP from embryonic day 9 to 18 compromised anxiety-/depression-like behaviors and elevated exploratory activity in adult offspring.Through cross analysis of SUP regulated-transcriptome by RNA sequencing and epigenome by reduced representation bisulfate sequencing,we found that the expression of CREB binding protein(CBP)was inversely correlated with DNA methylation level in its promoter.As a histone acetyltransferase,the elevated CBP in SUP offspring led to upregulation of H3K9 ac expression.Importantly,these enhanced CBP and H3K9 ac expressions in SUP-offspring were transmitted to their F1 ones,which displayed attenuated anxiety behavior as well.Further chromatin immunoprecipitation assay indicated that the binding of H3K9 ac on the promoter of glucocorticoid receptor,a vital factor in mood regulation,was greatly increased in hippocampus of SUP offspring,which resulted in remarkably enhanced GR expression.After brain stereotaxic injection of histone acetyltransferase p300/CBP inhibitor,the anxiolytic behavior in SUP-offspring was significantly reduced,indicating the causal association of CBP with SUP-offspring’s mood.Briefly,we firstly identified H3K9 ac as an epigenetic marker in choline-alleviated anxiety behaviors,and highlighted the long-term epigenetic regulation of gestational environment on moods.Meanwhile,the expression of food-anticipatory activity(FAA)is induced by restricted feeding(RF),and its entrainment requires food-entrainable oscillators,the neuroanatomical basis of which is currently unclear.Although RF impacts various hormones,sex-related differences in FAA are unclear.Here,we report significantly more FAA(wheel running)in male than in female mice and greater food consumption by male mice during RF.Sincegonadal hormones could be involved in the sex-specific difference in FAA,we compared sham and gonadectomized male and female wild-type mice.In gonadectomized mice,the sex difference in FAA was abolished,indicating a role for gonadal hormones in FAA.Further,plasma concentrations of the hormone ghrelin were higher in female than in male mice during ad libitum(AL)feeding,and RF induced a temporal advance in its peak in both sexes.RF also shifted the expression peak of the circadian gene m Per1 in the hippocampus and liver,although no sex difference was found in either the level or the cyclic phase of its expression.Per1Brdm1 mutant mice were still sexually dimorphic for FAA,but diminished FAA was noted in both male and female Per2Brdm1 mutant mice.In summary,our results imply that gonadal hormones contribute to the sex difference in FAA,possibly through modulating ghrelin activity.