title: Additive antidepressant-like effects of fasting with imipramine via modulation of 5-HT2 receptors in the mice.
abstract: Recently, studies show that intermittent fasting and caloric restriction may improve symptoms of depression. However, there is little scientific evidence regarding the literature on the antidepressant-like effects of acute fasting. The present study aims to investigate the antidepressant-like effects and its influence on brain levels of the transcription factor cAMP response element-binding protein (CREB) and its phosphorylated form (p-CREB) in different time periods of fasting mice. Furthermore, the additive antidepressant-like effects of fasting with imipramine and the possible involvement of the 5-HT2 receptors were examined. In the present study 9h, but not 3h and 18h of fasting significantly reduced immobility time in the forced swimming test (FST) without alteration in locomotor activity in the open field test. 9h fasting also enhanced the ratio of p-CREB/CREB in the frontal cortex and hippocampus. Co-administration of 9h of fasting and imipramine (30mg/kg, i.p) produced the additive antidepressant-like effects in the FST and increased the ratio of p-CREB/CREB. Meanwhile, the additive effects were partially reversed by treatment with a 5-HT2A/2C receptor agonist, (±)-1-(2, 5-dimethoxy-4-iodophenyl)-2-aminopropane hydrochloride (DOI) (5mg/kg, s.c). Furthermore, the antidepressant-like effects of 9h fasting was also blocked by DOI compared to the non-fasting control group. Serum corticosterone level, but not 5-HT and noradrenaline, was significantly increased in a time-dependent manner following different time periods of fasting. Taken together, these results suggest that acute fasting produces antidepressant-like effects via enhancement of the p-CREB/CREB ratio, and additive antidepressant-like effects of fasting with imipramine may be related to modulating 5-HT2 receptors.
authors.affiliation: National Engineering Laboratory for Druggable Gene and Protein Screening, Northeast Normal University, Changchun 130024, China; Jilin Key Laboratory of Animal Resource Conservation and Utilization, Northeast Normal University, Changchun 130024, China.
authors.forename: Bingjin
authors.initials: B
authors.lastname: Li
authors.forename: Jing
authors.initials: J
authors.lastname: Zhao
authors.forename: Jiayin
authors.initials: J
authors.lastname: Lv
authors.forename: Fang
authors.initials: F
authors.lastname: Tang
authors.forename: Lei
authors.initials: L
authors.lastname: Liu
authors.forename: Zhihui
authors.initials: Z
authors.lastname: Sun
authors.forename: Liang
authors.initials: L
authors.lastname: Wang
authors.forename: Sibongile P
authors.initials: SP
authors.lastname: Siwela
authors.forename: Yinuo
authors.initials: Y
authors.lastname: Wang
authors.forename: Yunong
authors.initials: Y
authors.lastname: Song
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Manchishi
authors.forename: Ranji
authors.initials: R
authors.lastname: Cui
mesh_terms: D000662:Amphetamines / Q000494:pharmacology; D000818:Animals; D000929:Antidepressive Agents, Tricyclic / Q000494:pharmacology*; D001921:Brain / Q000187:drug effects* / Q000378:metabolism*; D050882:CREB-Binding Protein / Q000378:metabolism; D003345:Corticosterone / Q000097:blood; D005215:Fasting; D005786:Gene Expression Regulation / Q000187:drug effects; D007099:Imipramine / Q000494:pharmacology*; D046353:Immobility Response, Tonic / Q000187:drug effects; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D009043:Motor Activity / Q000187:drug effects; D009638:Norepinephrine / Q000097:blood; D044348:Receptors, Serotonin, 5-HT2 / Q000378:metabolism*; D012701:Serotonin / Q000097:blood; D017366:Serotonin Receptor Agonists / Q000494:pharmacology; D013997:Time Factors
chemical_list: D000662:Amphetamines; D000929:Antidepressive Agents, Tricyclic; D044348:Receptors, Serotonin, 5-HT2; D017366:Serotonin Receptor Agonists; D012701:Serotonin; D050882:CREB-Binding Protein; D007099:Imipramine; C015952:4-iodo-2,5-dimethoxyphenylisopropylamine; D003345:Corticosterone; D009638:Norepinephrine
keywords: (±)-1-(2, 5-dimethoxy-4-iodophenyl)-2-aminopropane hydrochloride; 5-HT; 5-HT(2) receptor; ANOVA; BDNF; CREB; DOI; FST; Fasting; Forced swimming test; N-methyl-d-aspartate; NMDA; OFT; analysis of variance; brain derived neurotrophic factor; cAMP response element-binding protein; forced swimming test; i.p; intraperitoneal; open field test; p- CREB; p-CREB/CREB; phosphorylated cAMP response element-binding protein; s.c; serotonin; subcutaneous