A Natural Remedy for Insomnia: Picea mariana Essential Oils Exerts Effects through GABAergic and Serotonergic Modulation.

Abstract

Picea mariana essential oil (PMEOs) has been proven to possess anti-insomnia and antidepressant effects. However, research on the molecular mechanisms underlying its action remains limited. Therefore, our research seeks to deeply examine the anti-insomnia effects of PMEOs and elucidate the molecular and neurophysiological mechanisms involved. employing a mouse model of insomnia triggered by chlorophenylalanine administration, the study found that PMEOs at different doses (low, medium, and high) effectively inhibited weight loss, shortened sleep latency, and significantly extended the overall sleep duration in mice. Nissl staining showed that PMEOs at these doses reduced neuronal damage in insomnia mice. Immunohistochemical staining analysis further revealed that PMEOs increased the expression of GAD65, GABAAα1, 5HT-2A, and 5HT-1A in insomnia mice in a non-dose-dependent manner. RT-qPCR data, consistent with the staining results, showed that PMEOs-L and PMEOs-M upregulated the expression levels of 5HT-2A and GABAAγ1, providing stronger molecular evidence for the anti-insomnia effects of PMEOs through protecting neurons and activating the expression of related neurotransmitters in the cortex, hippocampus, and hypothalamus. As a natural product, PMEOs, by regulating the balance of 5HT-1A, 5HT-2A, GABAAγ2, GABAAα1 neurotransmitters, and GAD65, demonstrate potential clinical application value in the treatment of insomnia, offering scientific reference for subsequent promotion and use.