Antidepressant-like effects of acupuncture via modulation of corticosterone, sex hormones, and hippocampal BDNF expression in male rats

• Published in: Brain research bulletin Vol. 173; pp. 53 - 65
• Main Authors: Dávila-Hernández, Amalia, González-González, Roberto, Guzmán-Velázquez, Sonia, Hernández Hernández, Olivia Tania, Zamudio, Sergio R., Martínez-Mota, Lucía
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-08-2021
• Subjects: Acupuncture; Acupuncture Therapy; Animals; Behavior, Animal - physiology; Brain-Derived Neurotrophic Factor - metabolism; Corticosterone; Corticosterone - blood; Depression; Depression - metabolism; Depression - therapy; Depressive Disorder - metabolism; Depressive Disorder - therapy; Disease Models, Animal; Estradiol; Gonadal Steroid Hormones - blood; Hippocampus - metabolism; Male; Rats; Rats, Sprague-Dawley; Social Isolation; Testosterone; Treatment Outcome; Corticosterone; ACTH; PVN; mRNA; cAMP; E2; Estradiol; CREB; FLX; T; BW; GnRH; AC; BDNF; FST; Depression; ER; AR; CORT; Testosterone; NA; PD; S-N-K; Social isolation; HPA; Acupuncture; 5-HT; HPG; ELISA
• ISSN: 0361-9230; 1873-2747
• DOI: 10.1016/j.brainresbull.2021.05.007

•Acupuncture produces antidepressant-like effects in social isolated rats.•Acupuncture recovers normal BDNF hippocampal levels in rats subjected to social isolation (SI).•Testosterone and corticosterone disturbances elicited by SI are reversed by acupuncture.•Neuroendocrine and brain molecular modulation plays a role in the antidepressant effect of acupuncture.
Post-weaning social isolated rodents exhibit pathophysiological changes associated with depression including adrenal axis hyperactivity, gonadal hormone level disturbances, molecular alterations in hippocampus, and immobility behavior in the forced swimming test (FST). Although acupuncture by absorbable thread implantation (acu-catgut, AC) elicits antidepressant-like effects in social isolated rats, AC effects on neuroendocrine and hippocampal molecular alterations have been less characterized.
To investigate the participation of gonadal hormones, corticosterone, and brain-derived neurotrophic factor (BDNF) hippocampal expression, on the AC antidepressant-like effects in social isolated male rats.
Sprague-Dawley male rats were raised in social isolation (SI) or standard conditions, for 11 weeks. AC (on Baihui (Du20), Yintang (E X-HN3), Shenshu (BL 23), Pishu (BL 20), Ganshu (BL 18), Xinshu (BL 15) and Guanyuan (Ren 4)), or Sham-AC (puncturing of acupoints without embedding the thread), was applied during the last three weeks of isolation period. Rats were evaluated in the FST; hormones plasmatic levels and hippocampal BDNF content were quantified by ELISA and Western blotting, respectively.
Social isolated rats showed more immobility in the FST and had lower testosterone and estradiol levels, higher corticosterone levels, and reduced hippocampal BDNF content than controls. BDNF level in hippocampus inversely correlated to depression-like behavior. AC but not sham-AC normalized immobility behavior, steroid hormone levels, and BDNF content, as in rats raised in a social environment.
AC antidepressant effect could be related to an improvement of hippocampal BDNF protein expression, as well as corticosterone and sex hormones disturbances associated with prolonged exposure to stress caused by social isolation. Present findings have implications for depression treatment in individuals early exposed to stress.