ATAS-EMIT Activates the 5-HT/AC/cAMP Pathway to Ameliorate Insomnia in PCPA Insomniac Rats

Insomnia may lead to or be co-morbid with mental disorders. However, available treatments have significant side effects. Time-acupoints-space acupuncture, eight methods of intelligent turtle (ATAS-EMIT), as a low-hazard insomnia treatment, has been focused on.

Thirty-six rats were randomly divided into 4 groups: normal (Control), insomnia (Model), ATAS-EMIT treatment (Treatment), and sham acupuncture treatment (Sham). Behavioral experiments were used to assess the treatment of ATAS-EMIT for insomnia. ELISA, Western blot, and immunofluorescence staining were used to detect the expression of 5-HT, AC, cAMP, 5HT_1A receptor (5HT_1AR), and 5HT_2A receptor (5HT_2AR) in rat hippocampus. Transcriptome sequencing was used to explore more therapeutic mechanisms.

ATAS-EMIT treatment significantly reduced anxiety-like behaviors and activities in PCPA insomniac rats in the open field test. Additionally, ATAS-EMIT significantly shortened the sleep latency period in insomnia-prone rats while prolonging both sleep duration and hanging rest time. These behavioral studies suggest that ATAS-EMIT is a treatment for insomnia. The insomnia-related indicators showed that ATAS-EMIT significantly activated the 5-HT/AC/cAMP pathway, promoted the expression of the 5HT_1AR, and inhibited the expression of the 5HT_2AR for therapeutic purposes. Subsequent transcriptome sequencing revealed that ATAS-EMIT-treated DEGs were enriched for multiple insomnia-related functions such as phototransduction, stimulus-response, and tryptophan metabolism. Six key genes, Cngb1, Cabp4, Sag, Tyr, Trpm1, and Adipoq, were screened and validated.

ATAS-EMIT significantly improved insomnia symptoms in PCPA insomniac rats, and activation of the 5-HT/AC/cAMP pathway was involved. Various mechanisms, such as phototransduction, tryptophan metabolism, and reduction of stimulation, contributed to the therapeutic effects of ATAS-EMIT.