The effects of a standardized Acanthopanax koreanum extract on stress-induced behavioral alterations in mice

• Published in: Journal of ethnopharmacology 2013-07, Vol.148 (3), p.826-834
• Main Authors: Jung, Jun Man, Park, Se Jin, Lee, Young Woo, Lee, Hyung Eun, Hong, Sung In, Lew, Jae Hwan, Hong, Eunyoung, Shim, Jae Seok, Cheong, Jae Hoon, Ryu, Jong Hoon
• Format: Article
• Language: English
• Subjects: Acanthopanax koreanum; Animals; Anti-Anxiety Agents - pharmacology; Anti-Anxiety Agents - therapeutic use; Antidepressive Agents - pharmacology; Antidepressive Agents - therapeutic use; Anxiety; Anxiety - blood; Anxiety - drug therapy; Anxiety - physiopathology; bark; Behavior, Animal - drug effects; corticosterone; Corticosterone - blood; Depression; Depression - blood; Depression - drug therapy; Depression - physiopathology; Eleutherococcus; Hippocampus - cytology; Hippocampus - drug effects; Male; medicine; Medicine, Korean Traditional; Mice; Mice, Inbred ICR; Neurogenesis - drug effects; Organ Size - drug effects; Phytotherapy; Plant Bark; Plant Extracts - pharmacology; Plant Extracts - therapeutic use; Plant Roots; Restraint, Physical; roots; spleen; Spleen - drug effects; Spleen - pathology; Stress; Stress, Psychological - blood; Stress, Psychological - drug therapy; Stress, Psychological - physiopathology; swimming
• ISSN: 0378-8741; 1872-7573
• DOI: 10.1016/j.jep.2013.05.019

The roots and stem bark of Acanthopanax koreanum Nakai (Araliaceae), a well-known herbal medicine in Jeju Island, Korea, has been used as a tonic agent in treating stress-related states. Despite its popular application, the anti-anxiety or anti-depressive action of Acanthopanax koreanum is not yet known. This study aimed to determine the effects of Acanthopanax koreanum on stress-induced behavioral alterations such as anxiety and depression. Mice in the acute stress group were exposed to immobilization stress for 2h followed by electric foot shocks (0.5mA in 1s duration with a 10s inter-shock interval) for 2min, while sub-chronically stressed mice were exposed to these stresses for 2 weeks, once per day. 70% ethanolic extract of Acanthopanax koreanum (EEAK) (25, 50, 100, or 200mg/kg) was administered once or sub-chronically (for 2 weeks) 1h prior to stress induction. Anxiety- or depression-like behavioral changes were evaluated using the elevated plus-maze (EPM) test and the forced swimming test (FST) a day after the final stress induction. Corticosterone levels and spleen weight were measured after conducting all the behavioral assays. The numbers of BrdU- or DCX-immunopositive cells in the hippocampal region of sub-chronically stressed mice were measured 2 days after EEAK treatment. The percentage of time spent in the open arms was decreased in both the acutely and chronically stressed mice. In the FST, the immobility time was increased by only chronic stress, but not by acute stress. Acute or sub-chronic administration of EEAK significantly prevented the anxiety- or depression-like behavioral changes caused by stress. EEAK also attenuated stress-induced decrease and increase of spleen weight and corticosterone levels, respectively. Furthermore, the sub-chronic administration of EEAK (100 or 200mg/kg, for 2 weeks) increased the number of BrdU-, doublecortin-, and neuropeptide Y-positive cells in the hippocampal region of the sub-chronically stressed mice. EEAK attenuated the behavioral and biochemical changes in acute or sub-chronic stressed mice. These results suggest the therapeutic potential of Acanthopanax koreanum for the treatment of stress-related neuropsychiatric disorders including anxiety disorders or major depressive disorder. [Display omitted]