[Effect of acupuncture on inflammatory response and oxidative stress in rats with depression].

Objectives: To observe the effect of acupuncture at "Baihui" (GV20), "Shenmen" (HT7) and "Taichong" (LR3) (an acupoint prescription "Jieyufang" for treatment of depression) on inflammatory response and oxidative stress in depression rats induced by chronic unpredictable mild stress (CUMS).

Methods: Forty male SD rats were randomly divided into control, model, medication and acupuncture groups, with 10 rats in each group. The depression model was established by CUMS stress stimulation for 28 days. Acupuncture was delivered at "Baihui" (GV20), "Shenmen"(HT7) and "Taichong"(LR3) for 20 min, once a day for 28 days. Rats of the medication group received gavage of paroxetine hydrochloride (3.3 mg/kg) once a day for 28 days. Depressive behavior was evaluated by body weight, sucrose preference and tail suspension test. The contents of interleukin (IL)-6, IL-1β, IL-10 in serum, and the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) and content of malondialdehyde (MDA) in hippocampus were detected by ELISA. H.E. staining was used to observe the morphological changes of hippocampus. The expression levels of nuclear factor-erythroid 2 related factor 2 (Nrf2) and Kelch-like epichlorohydrin-related protein factor 1 (keap1) in hippocampus were detected by Western blot.

Results: Compared with the control group, the body weight, sucrose preference index, contents of serum IL-10 and SOD, CAT and GSH-Px activities in the hippocampus, the expression level of Nrf2 protein were significantly decreased (P<0.05, P<0.01);while the tail-suspension immobility time, contents of serum IL-6, IL-1β and MDA in hippocampus, the expression level of keap1 were increased (P<0.01) in the model group. Relevant to the model group, all the indexes mentioned above were reversed in both medication and acupuncture groups (P<0.05, P<0.01). H.E. staining showed severe damage of hippocampal neurons, which was milder in medication and acupuncture groups.

Conclusions: EA of acupoint recipe "Jieyufang" can improve the depression-like behavior of CUMS rats, inhibit inflammatory response and oxidative stress, which may be related to its functions in activating Nrf2.