Antidepressant effects of Yuanzhi (Polygalae Radix) extract on chronic unpredictable mild stress-induced depression in rats: modulation of the NLRP3 inflammasome and NF-κB pathway

Objective To investigate the antidepressant effects of Yuanzhi(Polygalae Radix;PR)aqueous extract on chronic unpredictable mild stress(CUMS)-induced depression rat models and the underlying mechanisms.Methods A total of 40 male Sprague Dawley(SD)rats were randomly divided into control;model;low dose of PR(PR-L;0.5 g/kg);high dose of PR(PR-H;1 g/kg);and fluoxetine(10 mg/kg)groups;with 8 rats in each group.Except for the rats in control group;those in the other four groups underwent CUMS-induced depression modeling.PR and fluoxetine were administered intragastrically once daily;30 min prior to the CUMS procedure;for 14 consecu-tive days until the behavioral tests were performed.After CUMS modeling;the sucrose prefer-ence test(SPT);open field test(OFT);novelty-suppressed feeding test(NSFT);forced swim test(FST);and tail suspension test(TST)were employed to assess the pharmacological ef-fects of PR on the mitigation of depressive-like behaviors in rat models.Additionally;the en-zyme-linked immunosorbent assay(ELISA)was utilized to quantify the serum levels of tumor necrosis factor(TNF)-α;interleukin(IL)-6;and IL-1βin the rats.Western blot analysis was al-so conducted to evaluate the protein expression levels of nuclear factor kappa-B(NF-κB);in-ducible nitric oxide synthase(iNOS);cyclooxygenase-2(COX-2);nucleotide-binding oligomerization domain(NOD)-like receptor family pyrin domain containing 3(NLRP3);apoptosis-associated speck-like protein containing caspase recruitment domain(ASC);and caspase-1 in the hippocampal tissues of the rats.Immunofluorescence staining was per-formed to observe the morphological changes in ionized calcium-binding adapter molecule 1 positive(Iba-1+)cells in the dentate gyrus(DG)of rats with CUMS-induced depression.Results(i)Treatment with PR-H and fluoxetine resulted in significant enhancements in both the total distance and time the rats moved during tests(P<0.01 and P<0.05;respectively).Post-administration of PR-H and fluoxetine also led to statistically significant increase in su-crose preference among rats(P<0.05).Besides;PR-L;PR-H;and fluoxetine treatment markedly decreased the latency of ingestion(P<0.05;P<0.05;and P<0.01;respectively).As observed from the FST;PR-L;PR-H;and fluoxetine presented antidepressant effects on rats with CUMS-induced depression;leading to the reduction in time of their immobility(P<0.05;P<0.01;and P<0.01;respectively).The results of TST indicated reduced immobility time in rats receiving PR-H and fluoxetine treatment as well(P<0.01).(ii)Rats in model group showed an increase in the levels of Iba-1+microglia in their left and right brains in compari-son with control group(P<0.01).However;such increase was negated post PR treatment(P<0.01).Treatment with PR-L;PR-H;and fluoxetine considerably reduced the levels of inflam-matory factors(TNF-α;IL-1β;and IL-6;P<0.01).In addition;treatment of PR-L and PR-H ef-fectively counteracted the elevated levels of NLRP3;ASC;and caspase-1;and markedly down-regulated the expression levels of phosphorylated p65(p-p65);COX-2;and iNOS in rats’hip-pocampus(P<0.01).Conclusion Collectively;these findings indicate that PR exerts an antidepressant effect on rats with CUMS-induced depression partially through the modulation of the NLRP3 and NF-κB signaling pathways.

Shuganheweitang Ameliorates Chronic Unpredictable Mild Stress-Induced Depression-Like Behaviors in Rats through the PI3K/AKT/mTOR Pathway: Involvement of Amino Acids, Glycerophospholipids, and Energy Metabolism

Background: Depression is a typical psychosomatic disease. Shuganheweitang (SGHWT) is a clinical formula that effectively treats depression. However, the potential mechanism used by SGHWT to ameliorate depression-like behaviors is still unclear. This study investigated the effects of SGHWT on metabolic change in the liver and hypothalamus with signaling pathways involved in chronic unpredictable mild stress (CUMS)-induced depression in rats to explore the mechanism of the anti-depressive effect. Methods: A total of 52 rats were used to create a model of depression by CUMS combined with solitary rearing for 6 weeks. Open field test (OFT), sucrose preference test (SPT), forced swim test (FST), and body weight (BW) were performed to analyze the pharmacodynamic effects of SGHWT. H&E staining, Nissl staining, immunofluorescence, immunohistochemistry, and western blot were used to evaluate the mechanism of action. Untargeted metabolomics techniques by ultra-performance liquid chromatography-quantitative time-of-flight tandem mass spectrometry (UPLC-Q-TOF-MS/MS) were used to analyze all the metabolic differences in the liver and hypothalamus. Results: SGHWT improved CUMS-induced depression-like behaviors in vivo. SGHWT reduced hepatic c-Fos protein expression and increased hypothalamic c-Fos protein expression. Moreover, p-PI3K, p-AKT473, p-AKT308, and p-mTOR protein expressions were significantly downregulated in the liver and hypothalamus of CUMS rats. Notably, these alterations were reversed by the SGHWT administration. Furthermore, the metabolomic analysis identified 15 and 5 key differential SPT-associated metabolites in the liver and hypothalamus, respectively. Conclusion: This study suggests that SGHWT ameliorates chronic unpredictable mild stress-induced depression-like behaviors, by the involvement of amino acids, glycerophospholipids, energy metabolism, and the PI3K/AKT/mTOR pathway. Highlights: 1) Shuganheweitang was derived from the TCM herbal formula Sinisan. 2) SGHWT treatment reverses depression-like behaviors in CUMS-induced rats. 3) The mechanism of SGHWT on depression by the liver and hypothalamus metabolomics. 4) SGHWT regulates amino acids, glycerophospholipids, and energy metabolism. 5) SGHWT exerts antidepressant effects through the PI3K/AKT/mTOR pathway.

Dynamic changes of behaviors, dentate gyrus neurogenesis and hippocampal miR-124 expression in rats with depression induced by chronic unpredictable mild stress

The depression-like behavior phenotype,neurogenesis in the dentate gyrus and miR-124 expression in the hippocampus are the focus of current research on the pathogenesis of depression and antidepressant therapy.The present study aimed to clarify the dynamic changes of depression-like behavior,dentate gyrus neurogenesis and hippocampal miR-124 expression during depression induced by chronic stress to reveal pathological features at different stages of depression and to further provide insight into depression treatment.Chronic unpredictable mild stress depression models were established by exposing Sprague-Dawley rats to various mild stressors,including white noise,thermal swimming,stroboscopic illumination,soiled cages,pairing with three other stressed animals,cold swimming,tail pinch,restraint and water and food deprivation.Chronic unpredictable mild stress model rats underwent dynamic observation from 1 to 8 weeks and were compared with a control group(normal feeding without any stressors).To observe changes in the depression-like behavior phenotype during chronic unpredictable mild stress-induced depression,a sucrose preference test was used to evaluate the degree of anhedonia.An open-field test was used to evaluate locomotor activity and anxiety status.Compared with the control group,chronic unpredictable mild stress rats lost weight but did not have a depression-like behavioral phenotype at 1-4 weeks.Chronic unpredictable mild stress rats presented decreased sucrose preference and locomotor activity at 5-8 weeks.In addition,chronic unpredictable mild stress rats did not have significant anxiety-like behavior during 1-8 weeks of modeling.To observe neurogenesis dysfunctions and changes in neuronal number in the dentate gyrus during chronic unpredictable mild stress-induced depression,markers(DCX and DCX/BrdU)of neural proliferation and differentiation and the neuronal marker NeuN were assessed by immunofluorescence.Compared with the control group,neurogenesis and the neuronal number in the dentate gyrus did not change from 2 to 6 weeks;however,neural proliferation and differentiation in the dentate gyrus decreased,and the number of neurons decreased until the eighth week in the chronic unpredictable mild stress group.Real-time quantitative reverse transcription polymerase chain reaction assays and fluorescence in situ hybridization were used to measure the expression of hippocampal miR-124 during chronic unpredictable mild stress-induced depression.The results showed that the expression of hippocampal miR-124 was unchanged during the first 4 weeks but increased from 5 to 6 weeks and decreased from 7 to 8 weeks compared with the control group.These findings indicate that during chronic unpredictable mild stress-induced depression,the behavioral phenotype,miR-124 expression in the hippocampus,neurogenesis in the dentate gyrus and neuronal numbers showed dynamic changes,which suggested that various pathological changes occur at different stages of depression.All experimental procedures and protocols were approved by the Experimental Animal Ethics Committee of Guangzhou University of Chinese Medicine of China in March 2015.

Optimization of food deprivation and sucrose preference test in SD rat model undergoing chronic unpredictable mild stress

Background:The chronic unpredictable mild stress(CUMS)model has long been considered the best model for exploring the pathophysiological mechanisms underlying depression.However,there are no widely recognised standards for strategies for modeling and for behavioral testing.The present study aimed to optimize the protocols for food deprivation and the sucrose preference test(SPT)for the CUMS model.Methods:We first evaluated the effects of different long periods of food deprivation on the body weight of Sprague Dawley(SD)rats by testing food deprivation for 24 hours(8:00-8:00^+),food deprivation for 12 hours during the daytime(8:00-20:00)and food deprivation for 12 hours at night(20:00-8:00^+).Next,we established a SD rat CUMS model with 15 different stimulations,and used body weight measurement,SPT,forced swim test(FST),open field test(OFT)and Morris water maze(MWM)test to verify the success of the modeling.In the SPT,consumption of sucrose and pure water within 1 and 12 hours was measured.Results:Twelve hours of food deprivation during the daytime(8:00-20:00)had no effect on body weight,while 12 hours of food deprivation at night(20:00-8:00^+)and 24 hours of food deprivation(8:00-8:00^+)significantly reduced the mean body weight of the SD rats.When SPT was used to verify the successful establishment of the CUMS rat model,sucrose consumption measured within 12 hours was less variable than that measured within 1 hour.Conclusions:Twelve hours of food deprivation in the daytime(8:00-20:00)may be considered a mild stimulus for the establishment of a CUMS rat model.Measuring sucrose consumption over 12 hours is recommended for SPT.

Effect and mechanism of LW-AFC on chronic unpredictable mild stress-induced mood and cognition impairment of mice

OBJECTIVE To explore the effect and mechanisms of LW-AFC,a new formula derived fromLiuwei Dihuang decoction,on chronic unpredictable mild stress(CUMS)-induced mood and cogni.tion impairment in mice.METHODS C57 BL/6 J mice were randomly placed into seven groups(n=10):normal control group,CUMS group,Fluoxetine(10 mg·kg^(-1),once per day) group,Liuwei Dihuang decoction group(LW,10 g·kg^(-1),once per day),and LW-AFC(0.8 g·kg^(-1),1.6 g·kg^(-1),3.2 g·kg^(-1),once per day) group.The stressed group was given CUMS for 4 weeks to set up a chronic multiple-stressed model.LW and LW-AFC was oral administered a week prior to CUMS and until the end of the study(a total of 35 d),while fluoxetine was administrated orally for 4 weeks.The anxiety behavior was analyzed using the open field test(OFT) and elevated plus maze test(EPM).The depression behavior was ana.lyzed using the sucrose preference test(SPT) and forced swimming test(FST).Spatial cognition was evaluated using Morris water maze(MWM) test and working memory was evaluated using new object recognition test(NORT).RESULTS CUMS for 28 d increased depressive-and anxiety-like behaviors.LW-AFC(1.6 g·kg^(-1)) significantly increased the numbers of entries into the open arm and time in the open arm of CUMS mice(P<0.05).LW-AFC(3.2 g·kg^(-1)) increased sucrose consumption and de.creased the immobility time of FST(P<0.01) of CUMS mice.The MWM test showed that spatial learning andmemory in CUMS mice were remarkably affected relative to controls,whereas LW-AFC(3.2 g·kg^(-1)) im.proves cognitive functions(P<0.05).CONCLUSION The mood and theability of learning and memory of thestressed group can be affected after exposure to CUS.Oral administration of LW-AFC significant.ly improved CUMS-induced impairments of mood and cognition in mice.

Quercetin regulates depression-like behavior in CUMS rat models via TLR4/NF-κB signaling

Background:Depression is becoming increasingly prevalent around the world,imposing a substantial burden on individuals,families,as well as society.Quercetin is known to be highly effective in treating depression.However,additional research is needed to dissect the mechanisms of its anti-depressive effects.Methods:For this study,Sprague-Dawley(SD)rats were randomized into the control,model,quercetin,or fluoxetine group.The latter three groups were exposed to chronic unpredictable mild stress(CUMS)for 42 d.The first two groups received saline solution daily via oral gavage.Meanwhile,the quercetin group was orally administered a quercetin suspension(52.08 mg/kg)every day,while the fluoxetine group was orally administered a fluoxetine solution(2.08 mg/kg).Here,fluoxetine served as the positive control drug to compare the therapeutic effects of quercetin.The experimental period was 6 weeks.Depressive behaviors in rats were assessed through various physiological and behavioral measures.Additionally,pathological changes in hippocampal tissues were examined using Nissl staining.Serum cytokines were detected using an enzymelinked immunosorbent assay(ELISA),and immunohistochemistry was employed to quantify the levels and integral optical density(IOD)values of ionized calcium binding adaptor molecule-1(Iba-1)expression in the brain.Real-time fluorescence quantitative PCR(RT-qPCR)was utilized to evaluate the mRNA levels of inflammatory indicators as well as toll-like receptor 4(TLR4),and nuclear factor-κappa B P65(NF-κB P65)in hippocampus.Western blot(WB)technique was employed to observe the protein levels of TLR4,NF-κB P65,and phospho-NF-κB P65(p-NF-κB P65).Results:After 42 d of exposure to CUMS,rats exhibited a slow increase in body weight,a reduction in food intake,an abnormal preference for sugar water,and aberrant open-field behaviors.Pathological analysis revealed the disintegration,rupture,interruption,and disorganization of hippocampal neuronal cells after CUMS exposure,along with a decrease in Nissl bodies in the CA1 region.This was accompanied by the elevated expression of interleukin-1β(IL-1β),tumor necrosis factor-α(TNF-α),and interleukin-6(IL-6)in the serum and the upregulation of IL-1β,IL-6,and TNF-αmRNA expression in the hippocampus.Increases in Iba-1-positive cells and the IOD values of Iba-1 were detected in hippocampal microglia.Furthermore,TLR4 and NF-κB P65 mRNA and protein levels were upregulated in hippocampal tissues.Quercetin,an antidepressant,could alleviate depression-like symptoms in rats and downregulate inflammatory factors associated with the TLR4/NF-κB signaling pathway in hippocampal microglia,and its therapeutic effect was comparable to fluoxetine.Conclusion:In rat models of CUMS,quercetin may act as an antidepressant by inhibiting inflammation in hippocampal microglia via TLR4/NF-κB signaling pathway.These results offer experimental and theoretical support for applying quercetin in the clinical management of depression.

基于CUMS模型探究抑郁症对细菌感染的影响及作用

【目的】抑郁症是一种常见的精神疾病,对患者的身体健康有着深远的影响。抑郁症与较高的细菌感染风险相关;然而,这是否是一种因果关系,以及抑郁症如何影响感染仍不清楚。因此,本研究旨在通过构建慢性不可预测轻度应激(CUMS)模型,探究抑郁表型在小鼠细菌感染中的作用。【方法】小鼠经CUMS诱导4周,通过行为学测试评估抑郁表型。随后,小鼠腹腔注射肺炎克雷伯菌模拟细菌感染,感染后48 h收集血清和腹腔组织。苏木精-伊红染色(HE)观察组织病理学改变,酶联免疫吸附试验(ELISA)检测炎性因子水平。此外,对感染前收集的小鼠粪便样本进行肠道菌群16S rDNA基因测序分析,并检测未感染小鼠结肠组织中NF-κB/NLRP3信号通路的表达水平。【结果】行为学测试结果显示,与对照组相比,CUMS小鼠体质量显著降低(P<0.0001,t=5.426),蔗糖偏好率显著降低(P<0.001,t=4.937),游泳静止时间显著增加(P<0.001,t=16.37),旷场中央区域停留时间显著减少(P<0.01,t=3.575)。生存分析显示,与对照组小鼠相比,感染后CUMS小鼠的生存率显著降低(P<0.05)。HE染色结果显示,CUMS小鼠肝脏(P<0.05,t=4.025)、肾脏(P<0.05,t=2.828)、肠系膜(P<0.01,t=5.367)组织损伤程度明显加重。ELISA结果显示,炎症因子IL-6(P<0.01,t=3.365)、IL-1β(P<0.01,t=4.061)、TNF-α(P<0.01,t=4.460)和LPS(P<0.0001,t=27.24)水平升高。16S rDNA测序结果显示,CUMS小鼠肠道菌群结构发生改变,与对照组小鼠明显不同,表现出菌群失调。与对照组相比,CUMS小鼠结肠组织中NF-κB(P<0.01,t=6.825)和NLRP3(P<0.001,t=9.561)的表达水平升高。【结论】CUMS小鼠发生更严重的细菌感染。CUMS诱导的抑郁表型可能因为破坏肠道菌群组成和激活NF-κB/NLRP3信号通路,增加了小鼠对细菌感染的易感性。

柴归颗粒动态调控CUMS大鼠尿液代谢标志物抗抑郁机制研究

目的 基于1H-NMR动态代谢组学和整合网络药理学探究柴归颗粒调控慢性温和不可预知应激(CUMS)大鼠尿液代谢标志物发挥抗抑郁作用的关键途径和潜在靶点。方法 除对照组外,各组大鼠均进行7周CUMS造模,前4周仅造模,后3周ig给药1 h后造模并对盐酸文拉法辛(35 mg·kg^(-1))组和柴归颗粒(8.3 g·kg^(-1))组进行药物干预,通过称体质量、糖水偏爱实验、强迫游泳实验研究柴归颗粒的抗抑郁作用;收集各组大鼠不同时间节点的尿液,采用1H-NMR代谢组学监测柴归颗粒给药过程中尿液代谢标志物的动态变化规律,整合网络药理学分析挖掘其治疗抑郁症的关键途径和潜在靶点。结果与模型组比较,柴归颗粒显著增加大鼠的体质量(P<0.05),显著升高糖水偏爱率(P<0.01),显著减少游泳不动时间(P<0.05、0.01);柴归颗粒可以动态调控天冬氨酸等10个尿液代谢标志物接近正常水平,且不同代谢物回调至正常水平的给药周期不同,泛酸、马尿酸含量在柴归颗粒给药1周后显著回调(P<0.05、0.01);蛋氨酸、甲胺和天冬氨酸含量在柴归颗粒给药2周后显著回调(P<0.01);2-酮戊二酸、牛磺酸、丁酸、赖氨酸和乳酸含量在柴归颗粒给药3周后显著回调(P<0.05、0.01)。同时,网络药理学分析结果表明柴归颗粒可能通过调控丙氨酸、天冬氨酸和谷氨酸代谢这一关键途径发挥疗效,且其代谢途径上的GPT、GLUD1、GLUD2、GOT2等4个靶点可能是柴归颗粒治疗抑郁症的潜在靶点。结论 柴归颗粒可能通过调控丙氨酸、天冬氨酸和谷氨酸代谢这一关键途径发挥抗抑郁作用。

裙带菜多糖通过减轻海马氧化应激改善CUMS大鼠抑郁样行为

目的:探究裙带菜多糖(UPPs)对慢性不可预见性温和应激(CUMS)处理大鼠抑郁样行为及单胺类神经递质含量、氧化应激和下丘脑-腺垂体-肾上腺(HPA)轴的影响。方法:利用CUMS方法制备大鼠抑郁症模型,使用灌胃方法分别给予大鼠生理盐水(NS)、不同剂量UPPs干预。观察大鼠的一般状况并通过旷场试验(OFT)、糖水偏好试验(SPT)、强迫游泳试验(FST)检测大鼠的抑郁样行为,通过商品化试剂盒检测大鼠海马或血清中5-羟色胺(5-HT)、多巴胺(DA)和去甲肾上腺素(NE)、丙二醛(MDA)、超氧化物岐化酶(SOD)和过氧化氢酶(CAT)、促肾上腺皮质激素(ACTH)、皮质酮(CORT)活性或者水平,利用Western Blot法检测海马糖皮质激素受体(GR)蛋白的表达水平,利用苏木精-伊红(HE)染色观察大鼠海马的组织结构。结果:UPPs中、高剂量组大鼠抑郁样行为明显改善(P<0.05),UPPs高剂量组大鼠的海马5-HT、DA、NE含量均有提高(P<0.05),血清和海马的MDA含量均有降低(P<0.05)、SOD和CAT活性均有提高(P<0.05),血清ACTH、CORT含量均有降低(P<0.05);UPPs中剂量组海马MDA、CAT,血清SOD、ACTH、CORT均有改善(P<0.05);海马GR蛋白表达水平提升(P<0.05);海马齿状回病理改变明显改善。结论:UPPs能减轻CUMS大鼠的抑郁样行为,其作用机制可能与提高海马单胺类神经递质含量、减轻氧化应激损伤和HPA轴亢进有关。

Fluoxetine Ameliorates the Aggravation of UC Symptoms in C57BL/6 Mice Induced by CUMS

Objective Patients with chronic ulcerative colitis(UC)often have mental symptoms such as depression and anxiety,and stress can lead to gastrointestinal diseases.However,the correlation between mental stress and UC is unclear.In this paper,chronic unpredictable mild stress(CUMS)was utilized to evaluate the involvement of mental factors in the pathogenesis of UC.Methods The CUMS model was used to evaluate the direct/indirect involvement of mental factors in the pathogenesis of UC.The behavior was evaluated by the open field,forced swimming,and tail suspension tests.Body weight,the disease activity index(DAI)score,colon length,and HE staining of colon tissue were used to evaluate the action of CUMS and fluoxetine.Results The results showed that weight loss and the DAI score increased in CUMS mice,but they had no meaningful effect on colon length and morphological structure of colon tissue.However,CUMS aggravated dextran sulfate sodium(DSS)-induced colon length shortening and colon morphological structure damage.Fluoxetine significantly improved the DAI score,shortened colon length,and damaged morphology and structure of the colons induced by CUMS combined with DSS in mice.Fluoxetine also decreased the level of IL-6 in the serum and the TNF-αand IFN-γlevels of colon tissue.Fluoxetine simultaneously improved behavioral abnormalities induced by CUMS combined with DSS in mice.Conclusion CUMS aggravated the UC symptoms induced by DSS,and fluoxetine could improve the UC symptoms due to its improvement in the inflammatory level and behavioral abnormalities.

Effects of CUMS combined with CRS on hippocampal glial cells and synaptic plasticity in depressed mice

Objective:To explore the effects of CUMS combined with CRS on mouse hippocampal glial cells and synaptic plasticity-related proteins. Methods: Forty mice were randomly divided into normal group (n=20) and model group (n=20). The model group used CUMS combined with CRS to prepare a mouse model of depression for 7 weeks. The behavioral evaluation of the mice at 3 weeks and 7 weeks after modeling was performed by sugar water preference test, open field test and tail suspension test. After the experiment, the samples were collected, and the content of TNF-a in the hippocampus of mice was detected by enzyme-linked immunosorbent assay. Immunohistochemical method was used to detect the Iba-1 and GFAP MOD values of mouse hippocampal CA1 area, CA3 area and DG area. Western blot was used to detect the protein expression of Iba-1, GFAP, SYN1 and PSD-95 in the hippocampus. fluorescence quantitative PCR method was used to detect the expression of SYN1, PSD-95 mRNA in hippocampus. Results: At the 3rd week after modeling, the body weight, sugar water preference rate, total distance moved, number of standing uprights, and stay time in the central area of the mice in the model group were all lower than those in the normal group (P<0.05), and the tail suspension immobility time was longer than that in the normal group (P<0.01). After 7 weeks of modeling, the body weight, sugar water preference rate, total distance moved, number of erection times, central area residence time, and average movement speed of the mice in the model group were lower than those in the normal group (P< 0.05), the tail suspension immobility time was longer than that in the normal group (P<0.01). The contents of TNF-a in the hippocampus were higher than those in the normal group (P<0.05). The GFAP MOD value and the relative expression of GFAP protein in hippocampal CA1, CA3 and DG regions were significantly lower than those in the normal group (P<0.05). The Iba-1 MOD value and the relative expression of Iba-1 protein in hippocampal CA1, CA3 and DG regions were significantly higher than those in the normal group (P<0.05). The relative expression of SYN1 and PSD-95 protein and the relative expression of SYN1 and PSD-95 mRNA in the hippocampus were significantly lower than those in the normal group (P<0.05). Conclusion: After 3 weeks of CUMS and CRS modeling, the depression-like behavior of mice appeared, and the depression of mice was more obvious after 7 weeks of modeling. The depression mouse model made by CUMS combined with CRS method may be related to increased hippocampal inflammation, excessive activation of microglia, decreased number of astrocytes and decreased synaptic plasticity.

CUMS抑郁小鼠模型海马氧化损伤的研究及大黄酚的保护作用

目的:探讨大黄酚(Chrysophanol,CHR)对于慢性不可预见性温和刺激(CUMS)导致的抑郁小鼠氧化应激的影响。方法:采用CUMS方法建立小鼠抑郁模型,分析不同剂量大黄酚对小鼠抑郁样行为的变化和小鼠海马组织超氧化物歧化酶(SOD)和丙二醛(MDA)水平的影响。结果:CHR能显著增加抑郁模型小鼠的体重,提高糖水偏好百分比,显著降低小鼠海马体中MDA水平,显著升高小鼠海马体SOD水平。结论:大黄酚能有效改善CUMS大鼠的抑郁样行为,其机制可能与氧化应激的调控有关。

逍遥散对CUMS模型大鼠行为学及脑内单胺类神经递质的影响

目的:观察逍遥散对慢性温和不可预知应激(CUMS)模型大鼠的行为学及脑内单胺类神经递质含量的影响。方法:应用慢性温和不可预知应激程序对大鼠进行为期11周的造模,造模后3周,分别采用逍遥散(19.5g/kg、25.0g/kg)和丙咪嗪(15.0mg/kg)对模型大鼠进行为期8周的治疗。实验进程中,定期测定大鼠体重、糖水消耗量;应用开场实验测定大鼠爬行格子数和站立次数;造模、治疗结束后处死大鼠,解剖分离大鼠皮层和海马部位,采用荧光分光光度法测定5-HLAA、5-HT、DA和NE含量。结果:与正常对照组比较。大鼠造模后3周糖水消耗量、爬行格子数和站立次数均明显减少(P<0.01);与模型对照组比较,逍遥散19.5、25.0g/kg连续给药2周能显著增加糖水消耗量,但给药4周、7周对糖水消耗量影响不明显;与模型对照组比较,逍遥散25.0g/kg连续给药7周,对大鼠体重、爬行格子数和站立次数表现出提高趋势(P>0.05),逍遥散25.0g/kg连续给药8周,能明显提高模型大鼠皮层部位5-HT含量及海马部位5-HIAA含量(P<0.05,P<0.01)。结论:逍遥散对CUMS抑郁模型大鼠表现出抗抑郁作用,作用机制与影响脑内单胺类神经递质5-HT活性有关。

CUMS结合CRS对抑郁症小鼠海马神经胶质细胞及突触可塑性的影响

目的:探讨CUMS结合CRS对小鼠海马神经胶质细胞及突触可塑性相关蛋白的影响。方法:将40只小鼠随机分为正常组(n=20)、模型组(n=20)。模型组采用CUMS结合CRS的方法制备抑郁症小鼠模型,持续造模7周。采用糖水偏好实验、旷场实验及悬尾实验对造模3周、7周末小鼠进行行为学评估;实验结束后取材,酶联免疫吸附法检测小鼠海马TNF-a的含量;免疫组化法检测小鼠海马CA1区、CA3区、DG区Iba-1、GFAP MOD值;蛋白免疫印迹法检测海马Iba-1、GFAP、SYN1、PSD-95的表达;荧光定量PCR法检测海马SYN1、PSD-95 mRNA的表达。结果:造模3周末,模型组小鼠体质量、糖水偏好率、移动总距离、直立次数、中央区停留时间均低于正常组(P<0.05),悬尾不动时间长于正常组(P<0.01);造模7周后,模型组小鼠体质量、糖水偏好率、移动总距离、直立次数、中央区停留时间、平均运动速度均低于正常组(P<0.05),悬尾不动时间均长于正常组(P<0.01);海马TNF-a含量高于正常组(P<0.05);海马CA1、CA3、DG区GFAP MOD值及GFAP蛋白相对表达量均低于正常组(P<0.05);海马CA1、CA3、DG区Iba-1 MOD值及Iba-1蛋白相对表达量均高于正常组(P<0.05);海马SYN1、PSD-95蛋白相对表达量及SYN1、PSD-95mRNA相对表达量均低于正常组(P<0.05)。结论:经过CUMS结合CRS方法造模3周后,小鼠即可出现抑郁样行为,在造模7周后,小鼠的抑郁表现更明显。通过CUMS结合CRS方法制备的抑郁症小鼠模型可能与小鼠海马炎症水平升高,小胶质细胞过度活化、星形胶质细胞数量减少及突触可塑性下降有关。

Increased expression level of corticotropin-releasing hormone in the amygdala and in the hypothalamus in rats exposed to chronic unpredictable mild stress

Objective Corticotropin-releasing hormone（CRH）plays an important role in neuroendocrine,autonomic and behavioral responses to stressors.In the present study,the effect of chronic unpredictable mild stress（CUMS）on CRH neurons was investigated in rat brain.Methods The rats were exposed to one of the stressors each day for 21 d.Immunostaining was performed to detect the CRH-positive neurons in the paraventricular nucleus（PVN）of the hypothalamus and in amygdala.Results After the stress protocol,the animals showed a reduction in body weight gain as well as reduced sucrose preference and locomotor activity.Interestingly,the CRH neurons in both PVN and central nucleus of the amygdala（CeA）were stimulated by CUMS.The densities of CRH-containing neurons in both PVN and CeA were significantly higher than those in control group.Conclusion The CRH systems in PVN and CeA may both contribute to depression-like behaviors during CUMS.

基于BDNF通路探讨樱桃叶水煎液对CUMS大鼠的抗抑郁作用机制

目的探讨樱桃叶水煎液对慢性不可预知性温和应激(CUMS)模型大鼠的抗抑郁作用及可能机制。方法将雄性Sprague-Dawley(SD)大鼠随机分为空白组、CUMS模型组、盐酸氟西汀组(2 mg·kg^(-1))以及樱桃叶水煎液低、中、高剂量组(1.8、2.7、3.6 g·kg^(-1))。复制CUMS模型,采用强迫游泳实验、悬尾实验和糖水偏好实验观察大鼠行为学变化;酶联免疫吸附实验(ELISA)测定大鼠血清促肾上腺皮质激素(ACTH)含量;Western Blot法测定大鼠海马组织中脑源性神经营养因子(BDNF)、酪氨酸激酶受体B(TrkB)、Ras相关C3肉毒杆菌毒素底物1(Rac1)、LIM激酶1(LIMK1)、丝切蛋白(cofilin)的表达水平。结果(1)与空白组比较,CUMS模型组大鼠强迫游泳实验和悬尾实验的不动时间增加(P<0.01),糖水偏好系数下降(P<0.01);血清ACTH水平上调(P<0.01);海马组织BDNF、TrkB、Rac1、LIMK1、cofilin蛋白表达降低(P<0.01)。(2)与CUMS模型组比较,樱桃叶水煎液干预后大鼠强迫游泳实验和悬尾实验的不动时间减少(P<0.05,P<0.01),而糖水偏好系数上升(P<0.01);血清ACTH水平下降(P<0.01);海马组织BDNF、TrkB、Rac1、LIMK1、cofilin蛋白表达增强(P<0.05,P<0.01)。结论樱桃叶水煎液具有一定的抗抑郁作用,其机制可能与调节BDNF/TrkB及其下游的Rac1/LIMK1/cofilin信号通路有关。

茶氨酸联合γ-氨基丁酸改善CUMS大鼠抑郁症状的研究

目的:观察L-茶氨酸和γ-氨基丁酸(γ-aminobutyric acid,GABA)联合干预对慢性不可预知温和刺激(CUMS)模型大鼠抑郁症状的缓解作用。方法:采用CUMS法建立抑郁症大鼠模型,不同剂量L-茶氨酸和GABA混合物或西酞普兰连续灌胃45 d,期间持续CUMS刺激。另设对照组,常规饲养。监测大鼠体重变化、糖水偏好程度、以及旷场实验水平运动、垂直运动等行为学指标,测定大鼠血清及脑组织中五羟色胺(5-HT)、多巴胺(DA)、白介素-6(IL-6)、脑源性神经营养因子(BDNF)、β-内啡肽(β-EP)的水平。结果:与对照组比较,CUMS大鼠体重、糖水消耗百分比、旷场水平和垂直运动显著降低(P<0.05);与模型组比较,茶氨酸联合GABA干预可显著增加大鼠体重增量、糖水消耗百分比,运动距离和站立次数(P<0.05),抑郁大鼠血清及脑组织中5-HT、DA以及BDNF、β-EP的含量增加(P<0. 05),降低IL-6的水平(P<0. 05)。结论:L-茶氨酸和GABA联合干预对CUMS诱发的抑郁症有一定改善作用,且高剂量的作用更为显著。

不同饮食模式对CUMS诱导的小鼠焦虑抑郁样行为的影响

为探究不同饮食模式对小鼠焦虑抑郁样行为的影响,采用慢性不可预见性温和应激(chronic unpredictability mild stress,CUMS)模型,将C57BL/6小鼠随机分为正常饮食组(normal diet,ND)、正常饮食应激组(normal diet stress,NDS)、高脂饮食组(high fat diet,HFD)和高脂饮食应激组(high fat diet stress,HFDS),对小鼠的行为、体质量、脂质和神经递质等指标进行测定。结果显示,与ND组相比,HFD组小鼠糖水偏好显著降低,旷场试验中总运动距离、进入中心区域次数和跨格次数降低,HFDS组部分行为学指标较HFD组更低,且HFDS组部分行为学指标低于NDS组;HFD组体质量、体脂比、总胆固醇(TC)和甘油三酯(TG)水平最高,CUMS显著降低高脂饮食和正常饮食小鼠的体脂比、TC和TG水平,且与NDS组相比,这些脂质指标水平在HFDS组更低。结果表明,高脂饮食易诱导焦虑抑郁样行为,且高脂饮食会加重CUMS诱导的焦虑抑郁样行为,其机制可能与脂质代谢、中枢神经递质代谢途径有关。

毛蕊花糖苷通过调控BDNF-TrkB信号通路改善CUMS大鼠的抑郁样行为

目的:观察毛蕊花糖苷(acteoside)对慢性不可预见性温和应激(chronic unpredictable mild stress,CUMS)大鼠抑郁样行为的影响,并探讨脑源性神经营养因子-原肌球蛋白受体激酶B(brain-derived neurotrophic factor-tropomyosin receptor kinase B,BDNF-TrkB)信号通路在其中的作用机制。方法:采用CUMS结合孤养的方式制备抑郁模型大鼠,成模后随机分为模型组、盐酸氟西汀(20 mg/kg)组和毛蕊花糖苷(30 mg/kg、60 mg/kg和120 mg/kg)组,每组18只,另取18只正常大鼠作为对照组,连续灌胃给药3周。采用强迫游泳实验和糖水偏好实验检测大鼠抑郁样行为的变化;免疫荧光和Western blot法检测大鼠海马BDNF-TrkB信号通路相关蛋白的表达情况;ELISA法检测脑组织中单胺类神经递质5-羟色胺(5-HT)、多巴胺(DA)和去甲肾上腺素(NE)的含量。结果:与对照组比较,模型组大鼠强迫游泳不动时间明显延长,糖水偏好量明显下降,海马BDNF和TrkB的表达均明显降低,脑组织中5-HT、DA和NE含量均显著减少;与模型组比较,盐酸氟西汀组和毛蕊花糖苷各剂量组以上各检测指标均得到显著逆转(P<0.05)。结论:毛蕊花糖苷可能通过上调海马BDNF-TrkB信号通路、增加脑内单胺类神经递质含量而改善CUMS大鼠的抑郁样行为。

青藤碱调控CUMS抑郁大鼠突触可塑性及其对Notch和mTOR信号通路的影响

目的:探究青藤碱(Sin)对慢性不可预见性温和应激(CUMS)所致抑郁大鼠症状的影响及可能的机制。方法:120只雄性健康SD大鼠随机分为对照(Ctrl)组、CUMS组、氟西汀(Fluo)组和Sin组(n=30)。建立CUMS抑郁大鼠模型,并分别给予Fluo(20 mg·kg^(−1)·d^(−1))或Sin(30 mg·kg^(−1)·d^(−1))灌胃治疗。通过检测体重、糖水实验及行为学检测抑郁症状;高尔基染色和苏木素-伊红染色分别检测树突棘密度和观察海马结构;qPCR和Western blot检测突触重塑相关蛋白脑源性神经营养因子(BDNF),Notch信号通路相关蛋白Notch1、Hes1和Jagged1,细胞凋亡相关蛋白Bcl-2和cleaved caspase-3(C-C3),以及哺乳动物雷帕霉素靶蛋白(mTOR)信号通路相关蛋白磷酸化mTOR(pmTOR)及磷酸化真核细胞翻译起始因子4E结合蛋白1(p-4EBP1)的变化;ELISA测定白细胞介素1β(IL-1β)、IL-6和肿瘤坏死因子α(TNF-α)的变化。结果:与Ctrl组相比,CUMS组大鼠体重、糖水偏好、旷场实验总距离和中央不动时间显著下降,强迫游泳不动时间显著增加(P<0.05)。CUMS组大鼠海马神经细胞排列紊乱,细胞间隙增大,多数细胞变性萎缩,树突棘密度减少,BDNF表达显著下调,Notch信号通路中Notch1、Hes1和Jagged1表达显著下调,细胞凋亡信号通路中Bcl-2表达下调,C-C3表达显著上调,p-mTOR和p-4EBP1下调,炎症因子IL-1β、IL-6和TNF-α表达显著上调,差异均有统计学意义(P<0.05)。Fluo和Sin均可逆转上述结果,且差异均有统计学意义(P<0.05)。结论:青藤碱能够缓解CUMS大鼠抑郁症状并改善突触可塑性,可能是通过激活Notch和mTOR信号通路,调节细胞凋亡和炎症反应来实现的。