Soyo-san reduces depressive-like behavior and proinflammatory cytokines in ovariectomized female rats
- Equal contributors
1 Acupuncture and Meridian Science Research Center (AMSRC), Kyung Hee University,1 Hoegi-dong, Dongdaemun-gu, Seoul 130-701, Republic of Korea
2 Department of Oriental Medical Science, College of Oriental Medicine, Graduate School, Kyung Hee University, Seoul 130-701, Korea
3 Department of Oriental Neuropsychiatry, Kyung Hee University Korean Medicine Hospital at Gangdong, Seoul 130-701, Korea
4 Department of Formulae Pharmacology, School of Korean Medicine, Graduate School of Gachon University, Seongnam, Gyeonggi-do 461-701, Korea
BMC Complementary and Alternative Medicine 2014, 14:34 doi:10.1186/1472-6882-14-34Published: 21 January 2014
Soyo-san is a traditional oriental medicinal formula, a mixture of 9 crude drugs, and it has been clinically used for treating mild depressive disorders. The role of pro- and anti-inflammatory cytokines in psychiatric disorders has been the focus of great research attention in recent years. In the present study, we detected the antidepressant effect of soyo-san in the ovariectomized and repeated stressed female rats.
This study was designed to evaluate the antidepressant-like effect of soyo-san on the forced swimming test (FST). The rats were randomly divided into the following groups: the nonoperated and nonstressed group (non-op), the nonoperated and stressed group (non-op + ST), the ovariectomized and stress group (OVX) and sham operated and stressed group (sham), the ovariectomized and stressed group (OVX + ST), the ovariectomized, stressed and soyo-san 100 mg/kg treated group (SOY100) and the ovariectomized, stressed and soyo-san 400 mg/kg treated group (SOY400). The rats were exposed to immobilization stress (IMO) for 14day (2 h/14day), and soyo-san (100 mg/kg and 400 mg/kg) was administrated during the same time. In the same animals, the levels of corticosterone and interleukin-1-beta (IL-1β) were examined in the serum. Also, the change of IL-1β expression in brain regions was examined after behavior test.
In the FST, the lower dose (100 mg/kg) of extract was effective in reducing immobility, along with an increase in swimming time. The serum levels of corticosterone and IL-1β in the SOY groups were significantly lower than those in the control group. In the brain, the expression of IL-1β positive neurons in the control group were significantly increased in the paraventricular nucleus (PVN) and hippocampus compared to the non-op. However, soyo-san groups significantly reduced the IL-1β-ir neurons in the PVN and hippocampal regions compared to the control.
The present results demonstrated that soyo-san effectively reduced behavioral and patho-physiological depression-like responses. Trial registration: Our results suggest that soyo-san may be useful for immune regulator in repeated stress-induced ovariectomized female rats.