Effects of acupuncture on regulating the hippocampal inflammatory response in rats exposed to post-traumatic stress disorder.

Data from clinical and experimental studies have verified the efficacy and safety of acupuncture in the treatment of post-traumatic stress disorder (PTSD). However, the concrete mechanism has not been well elucidated. The stress-induced activation of inflammatory response is involved in the development and pathogenesis of PTSD. Here, we aimed to investigate the effects of acupuncture on regulating the hippocampal inflammatory response in rats exposed to PTSD. Forty male rats were randomly divided into control, model, acupuncture and sertraline group. Within 1 day after adaptive feeding, all rats were exposed to single prolonged stress (SPS), except for the rats in the control group. Rats in acupuncture group were exposed to acupuncture intervention at the acupoints of Baihui (GV20) and Yintang (GV29), 20 min once per day for 15 days. Rats in sertraline group were exposed to a suspension of sertraline and distilled water (0.2 mg/ml), once per day for 15 days continuously. Body weight and elevated plus maze experiment were detected at different time-points to evaluate the behavioral changes of rats. HE staining method was used to observe the basic pathological morphological changes in hippocampus. Immunofluorescence staining method was used to observe the activation of hippocampal microglia. The content of IL-6 and IL-1ß in serum were detected by ELISA method. Compared with the control group, the body weight of rats in model group significantly decreased on 8 days, and the percentage of time in open arms and open arm entries decreased significantly on 15 days after SPS procedures, which indicated that SPS induced PTSD-like behavior in rats. Acupuncture exerted therapeutic effect. Simultaneously, the result of HE staining confirmed that SPS induced hippocampal morphological changes in SPS rats. Notably, acupuncture reversed the reduction and pathological injury to some extent. The results have also shown that acupuncture intervention effectively reversed the activated microglia of the hippocampus in rats. Moreover, the expression of IL-1ß in serum was significantly decreased by acupuncture intervention. In summary, the present study demonstrated that the role of acupuncture in eliminating PTSD-like behavior might be connected with reversing the pathological process of the inflammatory response mediated by the activation of microglia induced by SPS.

Acupuncture for brain diseases: Conception, application, and exploration.

The brain is probably the most complex organ in the human body. It has been the hot spot and direction of brain science research all over the world to deeply study the pathogenesis of various kinds of brain diseases and find effective treatment methods. Acupuncture is a nonpharmacological therapy of traditional Chinese medicine originating from ancient clinical practice. The research on the treatment of brain diseases by acupuncture has been constantly enriched and updated with the promotion of interdisciplinary research. In order to account for the current achievements in the field of acupuncture for brain diseases, this article reviews it in terms of conception, application, and exploration. Based on the literature review, we found that in the past decades, acupuncture has received widespread attention worldwide and many literatures have reported the clinical efficacy and underlying mechanisms of acupuncture in the treatment of brain diseases. Presently, the conception, application, and exploration of acupuncture in the treatment of brain diseases have evolved from empirical medicine to evidence-based medicine and precision medicine, and are experiencing a deeper understanding of the information about acupuncture regulating the brain function based on interdisciplinary research.

Serum NLRP3 Inflammasome and BDNF: Potential Biomarkers Differentiating Reactive and Endogenous Depression.

Background: The highly heterogeneous pathogenesis of depression and limited response to current antidepressants call for more objective evidence for depression subtypes. Reactive and endogenous depression are two etiologically distinct subtypes associated with different treatment responses. This study aims to explore the potential biomarkers that differentiate reactive and endogenous depressions. Methods: The clinical manifestations and biological indicators of 64 unmedicated mild-to-moderate depression patients (32 reactive depression patients and 32 endogenous depression patients) and 21 healthy subjects were observed. The 24-item Hamilton rating scale for depression (HAMD-24) was used to evaluate the severity of depression. Serum levels of depression-related biological indicators were measured by using the enzyme-linked immunosorbent assay. Results: The NLRP3 level of reactive depression was significantly lower than those of endogenous depression and healthy controls. There was a significant negative correlation between the BDNF level and the HAMD-24 total scores for patients with reactive depression. Conclusion: Our findings suggested the serum NLRP3 and BDNF levels could be potential biomarkers for detecting and evaluating the severity of reactive depression.

Antidepressant effect of electroacupuncture on modulating the expression of c-Fos/AP-1 through the JNK signaling pathway.

The effectiveness and safety of electroacupuncture (EA) for depression have been identified by abundant clinical trials and experimental findings. The c-Jun-NH(2)-terminal kinase (JNK) signaling pathway is considered to be involved in the antidepressant mechanism of EA. However, the antidepressant effect of EA via modulating the expression of c-Fos/activator protein-1 (AP-1) under the condition of JNK inhibition remains unexplored. In this study, we investigated the antidepressant effect and possible mechanism of EA in regulating the expression of c-Fos/AP-1 under the condition of JNK inhibition by SP600125 in rats exposed to chronic unpredictable mild stress (CUMS). The depression-like behaviors were evaluated by the body weight, sucrose preference test (SPT), and open field test (OFT). The expression levels of c-Jun in the hypothalamus, c-Fos in the pituitary gland, and c-Fos and AP-1 in the serum of CUMS induced rat model of depression were detected by ELISA. The results indicated that treatment with EA and fluoxetine can reverse the CUMS-induced depression-like behaviors in rats and can up-regulate the expression levels of c-Jun in the hypothalamus, c-Fos in the pituitary gland, and c-Fos and AP-1 in the serum. Of note, the data demonstrated that SP600125, the inhibitor of JNK signaling pathway, can exert synergistic effect with EA in regulating CUMS-induced abnormal activation of the JNK signaling pathway. The antidepressant effect of EA might be mediated by modulating the expression of c-Fos/AP-1.

Subthreshold depression may exist on a spectrum with major depressive disorder: Evidence from gray matter volume and morphological brain network.

BACKGROUND: Subthreshold depression (StD) is a prevalent condition that may increase the risk of incident major depressive disorder (MDD). However, the relationship between StD and MDD remains unclear. METHODS: A total of 153 adult subjects, including 53 drug-naive MDD, 50 StD and 50 healthy control (HC) subjects, underwent a T1-weighted magnetic resonance imaging scan, and the gray matter volume (GMV) alterations among the three groups were quantitatively analyzed using voxel-based morphometry (VBM). Then, to capture the whole-brain connectivity characteristics, we constructed morphological brain networks (MBN) based on the similarity among brain regions of individual VBM images and compared the network connection strengths among the three groups. RESULTS: The StD and MDD subjects had similar patterns of GMV reductions in the orbitofrontal cortex and left temporal gyrus, although the magnitude of the reductions was smaller in StD subjects. Moreover, a total of 21 morphological connections were significantly different among the three groups. For the majority of the different connections (15/21), the connection strength of the StD group took an intermediate position between that of the MDD and HC groups. LIMITATIONS: There is still a lack of a consistent definition of StD, and the age range of the subjects in this study was wide. Meanwhile the mechanisms and biological significance of the MBN remains to be clarified. CONCLUSIONS: These results may support the hypothesis that depression is better expressed as a spectrum and that StD exists on a spectrum with MDD.

[Acupuncture improved depressive behavior by regulating expression of hippocampal apoptosis-related factors in psychological stress-induced depression rats].

OBJECTIVE: To investigate the effect of acupuncture on behavior changes and the expression of reactive oxygen species (ROS), cytochrome C, cysteine-containing aspartate-specific proteases-3 (caspase-3), apoptosis inducing factor (AIF) in the hippocampus of rats exposed to chronic restraint stress (CRS), so as to provide experimental evidence for the prevention and treatment of depression. METHODS: Thirty two male SD rats were equally randomized into control, model, acupuncture and medication (Fluoxetine) groups according to the random number table. The depression model was established by chronic psychological stress stimulation (fasting, water deprivation, chronic restraint combined with solitary raising for 28 days). Manual acupuncture stimulation (2 circles/s) was applied to "Baihui" (GV20), "Yintang" (GV29) and bilateral "Sanyinjiao" (SP6) for 2 min, followed by retaining the needles for 20 min. Rats in the medication group were treated by gavage of Fluoxetine (0.18 mg/mL, 1 mL/100 g body weight). The treatment was conducted once daily for 28 days. The depression-like behavior was evaluated by using open-field test, sucrose preference test, and body weight. The content of ROS of the right hippocampus tissue was detected by using dichloro-dihydro-fluorescein diacetate (DCFH-DA) assay, and the expression levels of cytochrome C, caspase-3 and AIF proteins of hippocampus were determined by using Western blot. RESULTS: After 28 days' stress procedure, the depression rats in the model group showed a significant decrease in the numbers of crossing and rearing of open-field test, sucrose preference index and the body weight compared to the control group (P<0.01). The content of ROS and expression levels of cytochrome C, caspase-3 and AIF in the hippocampus of the model group were significantly increased relevant to the control group (all P<0.01). After the intervention and compared with the model group, the decreased levels of the numbers of crossing and rearing, body weight and sucrose preference index, and the up-regulated levels of content of ROS and expression of cytochrome C, caspase-3 and AIF proteins were all reversed in both acupuncture and medication groups (P<0.01，P<0.05), displaying an anti-depressant effect. The effect of acupuncture was significantly superior to that of medication in up-regulating the numbers of crossing and rearing (P<0.01, P<0.05), and in down-regulating the expression of caspase-3 (P<0.01). No significant differences were found between the medication and acupuncture groups in increasing the body weight and sucrose preference index, and in down-regulating the expression of cytochrome C and AIF proteins (P>0.05). CONCLUSION: Acupuncture intervention can significantly reduce ROS content and expression level of cytochrome C, caspase-3 and AIF proteins in the hippocampus possibly by inhibiting the chronic psychological stress-hippocampal oxidative stress-mitochondrial apoptotic pathway in psychological stress-induced depression rats, which may contribute to its effect in relieving depression.

[Effect of Acupuncture Intervention on Depression Behavior and Expression of ERK 1/2 and BDNF in Prefrontal Cortex in Chronic Unpredictable Mild Stress Induced Depression Rats].

OBJECTIVE: To investigate the effect of acupuncture intervention on the depression behavior and expression of extracellular signal-regulated protein kinases (ERK 1/2), p-ERK 1/2 and brain-derived neurotrophic factor (BDNF) in the prefrontal cortex of chronic unpredictable mild stress (CUMS) induced depression rats, so as to explore its antidepressant mechanism. METHODS: Sixty-four male SD rats were randomly divided into control, model, acupuncture, Fluoxetine, model ＋ Dimethyl sulfoxide (DMSO), model ＋ PD 98059(an ERK pathway inhibitor), acupuncture ＋ PD 98059 and Fluoxetine ＋ PD 98059 groups (n＝8 rats in each). The CUMS depression model was established by using chronic mild and unpredictable stress methods for 21 days. Manual acupuncture stimulation was applied to "Baihui" (GV 20) and "Yintang" (GV 29) for 10 min before modeling, once daily for 21 days. Fluoxetine hydrochloride suspension (1.8 mg•kg－1•d－1) was given to rats of the Fluoxetine group and Fluo-xetine ＋ PD 98059 group by gavage 30 min before CUMS. PD 98059 (dissolved in DMSO, 10 µL) was administered to rats of model ＋ PD 98059 group, acupuncture ＋ PD 98059 and Fluoxetine ＋ PD 98059 group, and DMSO (10 µL) to rats of model ＋ DMSO group by intracerebroventricular injection 1 h before CUMS. Sucrose consumption test was carried out to evaluate the depressive behavior. Western blot was performed to detect the expression of ERK 1/2, p-ERK 1/2 and BDNF of prefrontal cortex. RESULTS: Compared with the control group, the sucrose consumption and the expression levels of p-ERK 1/2 and BDNF protein in the prefrontal cortex were significantly reduced in the model and model＋DMSO group (P<0. 01). After the intervention, modeling induced decrease of the sucrose consumption, and p-ERK 1/2 and BDNF expression was significantly up-regulated in both acupuncture and Fluoxetine groups (P<0.01, P<0.05), but not in the model＋PD 98059, Fluoxetine ＋PD 98059 and acupuncture＋PD 98059 groups (P>0.05). No significant differences were found among the model＋PD 98059, Fluoxetine ＋PD 98059 and acupuncture＋PD 98059 groups in the sucrose consumption, and ERK 1/2, p-ERK 1/2 and BDNF expression levels (P>0.05), and in the expression levels of ERK 1/2 protein among the 8 groups (P>0.05). CONCLUSION: Acupuncture intervention has an anti-depressive role in CUMS induced depression rats, which may be related to its effects in up-regulating the expression of p-ERK 1/2 and BDNF in the prefrontal cortex tissue.