Isoflavones Alter Hypothalamic–Pituitary–Adrenal Axis Response Following Photoperiod Alteration. (15th May 2019)

• Record Type: Journal Article
• Authors: Bauman, Bradly M.; Buban, Katelyn N.; Russell, Ashley L.; Handa, Robert J.; Wu, T. John
• Is Part Of: Neuroscience. Volume 406(2019)
• Page Start: 268
• Page End: 277
• Publication Date: 2019-05-15
• Subjects: aBNST anterior bed nucleus of the stria terminalis -- ACTH adrenocorticotropic hormone -- AMY amygdala -- ANOVA analysis of variance -- AVP arginine vasopressin -- CORT corticosterone -- CRF corticotropin releasing factor -- CRFR1 corticotropin releasing factor receptor 1 -- CRFR2 corticotropin releasing factor receptor 2 -- CYP11β1 11-β hydroxylase -- dHPC dorsal hippocampus -- ERα estrogen receptor alpha -- ERβ estrogen receptor beta -- ERE estrogen response element -- GR glucocorticoid receptor -- HPA hypothalamic–pituitary–adrenal -- HSD11β1 11β-hydroxysteroid dehydrogenase 1 -- IF isoflavone free -- LD light–dark -- MC2R melanocortin 2 receptor -- MR mineralcorticoid receptor -- pBNST posterior bed nucleus of the stria terminalis -- PFC prefrontal cortex -- POMC pro-opiomelanocortin -- PVN paraventricular nucleus -- SCN suprachiasmatic nucleus -- vHPC ventral hippocampus; corticosterone -- photoperiod -- isoflavones -- stress; Neurochemistry -- Periodicals; Neurophysiology -- Periodicals; Neurology -- Periodicals; Neurochimie -- Périodiques; Neurophysiologie -- Périodiques; Neurochemistry; Neurophysiology; Electronic journals; Periodicals; Electronic journals; 612.8
• DOI: 10.1016/j.neuroscience.2019.03.013
• Languages: English
• ISSNs: 0306-4522

Abstract

Abstract: Photoperiod and diet are factors known to modulate the hypothalamic–pituitary–adrenal (HPA) axis. Specifically, shifts in photoperiod have been previously linked with affective and anxiety disorders. Furthermore, isoflavones have been shown to mediate behavioral outcome in response to the environment of the animal. Here, we investigated the effect of photoperiod alteration on the HPA axis and how the addition of isoflavones might modulate the response to stress. Male C57BL/6J mice were maintained on either a 12:12 or a 16:8 light–dark (LD) cycle for 10 days, and fed a diet of either standard rodent chow or an isoflavone free (IF) chow beginning 3 weeks prior to light alteration. Consistent with previous work, mice in the shorter active period (16:8 LD cycle) showed increased basal corticosterone (CORT) secretion. In the absence of isoflavones, this response was attenuated. Increases in mineralcorticoid (MR) and glucocorticoid (GR) receptor mRNA expression were seen in the pituitary following photoperiod alteration. However, animals fed the standard isoflavone rich chow showed increases in the ratio of MR:GR mRNA in the anterior bed nucleus of the stria terminalis following photoperiod alteration. Decreases in corticotrophin-releasing factor receptor 1 (CRFR1) mRNA expression were seen in animals fed the IF chow in the amygdala, prefrontal cortex and ventral hippocampus. These data suggest that alterations in CORT secretion following photoperiod alteration may be mediated through differences in CRFR1 gene expression or changes in MR:GR mRNA ratios. These findings provide insight into the potential mechanisms by which the HPA axis adapts to photoperiod and diet. Highlights: Photoperiod alteration dysregulates the hypothalamic–pituitary–adrenal axis. Isoflavone free chow attenuates photoperiod induced changes in corticosterone. Glucocorticoid receptors are altered in the brain and pituitary.