Study of the Central Injection Effects of Chrysin on Behavioral and Intra Hypothalamic Gene Expression Levels of <i>CRH</i> and <i>CGRP</i> in Male Rats

Chrysin is a natural flavonoid with several demonstrated neuro-pharmacological effects in brain areas related to anxiety. However, the intra-hypothalamic molecular mechanisms underlying the anxiolytic effects of chrysin remain unclear.

The current study revealed the effects of chrysin on hypothalamic corticotrophin-releasing hormone ( CRH ) and calcitonin gene-related peptide ( CGRP ) gene expression levels in a rat model of stress.

Thirty male Wistar rats weighing 200 ± 10 g were divided into six groups for this investigation. Acute restraint stress was induced in the animals for 2 hours. Intact or stress-induced rats received 20 or 40 µg of chrysin via the third cerebral ventricle, respectively. Open-field and forced swimming tests were performed to evaluate stress-related behaviors. Hypothalamic samples were then removed, and real-time polymerase chain reaction (PCR) was used to measure relative gene expression.

The results showed that in the rats receiving chrysin, CRH and CGRP gene expression levels were significantly decreased compared to the stress group. Additionally, chrysin injection reduced anxiogenic behaviors.

Chrysin decreased the expression of hypothalamic CRH and CGRP genes in stressed rats.