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.

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。

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。

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.

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.

Jobelyn^(■), a Sorghum-Based Nutritional Supplement Attenuates Unpredictable Chronic Mild Stress-Induced Memory Deficits in Mice

The ability of an organism to adapt to aversive stressful situations or life challenging circumstances is very crucial to its state of health and survival. However, breakdown in adaptation due to persistent uncontrollable stress, leads to impairment of bodily functions and onset of a variety of pathological disorders especially memory decline. This study was designed to evaluate the effect of Jobelyn&reg;(JB), a potent antioxidant sorghum-based food supplement on unpredictable chronic mild stress (UCMS)-induced memory impairment in mice. Male Swiss mice were given JB (5 - 50 mg/kg, p.o) 30 min prior to exposure to UCMS for 14 consecutive days before testing for memory. Thereafter, the serum corticosterone level was estimated by using ELISA kits. The levels of malondialdehyde (MDA) and glutathione (GSH) as well as acetylcholinesterase activity were estimated in the brain homogenate using spectrophotometer. Histology of the brain tissues and estimation of the populations of viable neurons in the hippocampal region were done after staining with hematoxyline and eosin. Our results showed that JB reversed memory impairment and suppressed corticosterone concentrations induced by UCMS. Moreover, JB reduced oxidative stress in the brain of UCMS-mice as shown by decreased MDA levels and elevated GSH concentrations. It also decreased brain acetylcholinesterase activity when compared with chronic stress group (p < 0.05). Furthermore, JB (5 - 10 mg/kg, p.o) offered significant protection against UCMS-induced degeneration and death of neuronal cells of the cornu ammonis 3 (CA3) of the hippocampal region of the brain indicating neuroprotection. Taken together, these findings suggest that JB attenuates memory deficits induced by UCMS in mice and may be useful therapeutically for stress-related cognitive dysfunctions. The reduction in the levels of serum corticosterone, antioxidation, neuroprotection and inhibition of cholinesterase enzyme might be contributing significantly to the positive effect of JB on memory in mice exposed to unpredictable chronic mild stress.

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。

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。

Vitamin D_(3) attenuates anxiety-like behavior in long-term ovariectomized rats with unpredictable mild stress

The impact of various vitamin D3(VD3)doses(1.0,2.5,or 5 mg/kg,s.c.)in mitigating the negative consequences of chronic unpredictable mild stress(CUMS)was investigated.Adult female rats with long-term estrogen deficiency were assessed using the sucrose preference test(SPT),the elevated plus-maze(EPM),the light/dark test(LDT),and the open-field test(OFT)to measure anhedonia-like and anxiety-like behavior.The corticosterone(CS)and adrenocorticotrophic hormone(ACTH)concentrations in blood serum and the brain-derived neurotrophic factor(BDNF)expression in the hippocampus of long-term ovariectomized(OVX)rats were measured by ELISA kits and/or western blotting.Treatment with VD3(5.0 mg/kg),similarly to fluoxetine(10.0 mg/kg),significantly reduced the anhedonia profile in the SPT and anxiety-like behavior in the EPM and LDT,and CS and ACTH levels in blood serum.It also elevated BDNF levels in the hippocampus of long-term OVX/CUMS compared to OVX/CUMS/solvent rats.Thus,these findings suggest that VD3(5.0 mg/kg)administration might attenuate the anxiety-like profile in long-term OVX adult rats subjected to the CUMS.This might occur via activation of the BDNF signaling pathway in the hippocampus and via restoration of CS and ACTH levels in blood serum.

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。

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。

GSK3β/β-catenin信号通路在运动和氟西汀改善CUMS小鼠抑郁行为中的作用机制

目的探究游泳运动和氟西汀对CUMS小鼠抑郁行为及GSK3β/β-catenin信号通路的影响。方法采用雄性C57BL/6小鼠,随机分为5组,每组8只:Con组,即普通控制组;CUMS组,实验小鼠接受7周的慢性不可预见性温和应激;CUMS+Saline组,从应激的第4周开始腹腔注射生理盐水4周;CUMS+Flu组,从应激的第4周开始腹腔注射抗抑郁药物氟西汀(Fluoxetine,Flu)4周;CUMS+Swim组,从应激的第4周开始进行游泳训练4周。实验干预结束后,所有小鼠接受行为学检测。断头处死取海马组织,采用Western blotting技术检测相关基因的蛋白表达水平。结果 (1)行为学实验显示,与Con组相比,CUMS组糖水偏好显著降低(P<0.05),强迫游泳(FST)和悬尾实验(TST)不动时间显著增加(P<0.01),开场实验(OFT)探洞次数显著减少(P<0.05);与CUMS+Saline组相比,CUMS+Flu组糖水偏好显著增加(P<0.05),FST和TST不动时间显著减少(P<0.05),OFT探洞次数显著增加(P<0.01);与CUMS组相比,CUMS+Swim组糖水偏好无显著变化,FST(P<0.05)和TST(P<0.01)不动时间显著减少,OFT探洞次数显著增加(P<0.01)。(2)Western blotting实验显示,与Con相比,CUMS组海马组织中pGSK3β(Ser9)、β-catenin的蛋白水平显著降低(P<0.05);与CUMS+Saline相比,CUMS+Flu组海马组织中β-catenin的蛋白水平显著升高(P<0.05),GSK3β、pGSK3β(Ser9)、pGSK3β(Tyr216)的蛋白水平无显著变化;与CUMS组相比,CUMS+Swim组海马组织中GSK3β(P<0.01)、pGSK3β(Ser9,P<0.05)、β-catenin(P<0.05)的蛋白水平显著升高。结论运动和氟西汀均可缓解CUMS所致的小鼠抑郁行为;慢性应激诱导抑郁行为可能涉及GSK3β/β-catenin信号通路的功能紊乱;运动和氟西汀均提高小鼠对慢性应激的耐受性从而控制抑郁病理进程,二者发挥作用的分子机制有所不同,运动缓解抑郁行为可能涉及纠正海马组织中GSK3β/β-catenin信号通路紊乱,而氟西汀缓解抑郁行为可能是非GSK3β/β-catenin依赖性的。研究论证了慢性应激期的运动干预效果媲美于抗抑郁药物氟西汀,并提出了相应的分子行为学依据。深入探究不同抑郁病理期的运动干预模式及其潜在的分子机制,将为运动抗抑郁的转化研究提供新靶向。

白金胶囊对CUMS诱导的抑郁症大鼠模型行为学及脑内单胺类神经递质的影响

目的观察白金胶囊对慢性不可预知温和应激(CUMS)致抑郁症大鼠模型行为学及脑内单胺类神经递质的影响。方法采用慢性不可预知温和应激结合孤养的方法建立抑郁症大鼠模型,造模7周后,采用白金胶囊(12.6 g/kg、4.2 g/kg、1.4 g/kg)和盐酸氟西汀(3.5 mg/kg)连续灌胃4周进行治疗,给药期间继续实施应激方案,共计11周,另设正常对照组,常规饲养。监测糖水偏嗜度、以及动物在旷场中的水平运动、垂直运动等行为学指标;实验终点,采用高效液相-电化学法测定大鼠脑皮层、海马部位单胺类神经递质(5-HT、DA、NE及其代谢产物)的水平。结果与正常对照组比较,模型大鼠造模7周后,体重、糖水消耗百分比、旷场水平运动和垂直活动明显降低(P<0.05,P<0.01);与模型组比较,白金胶囊连续给药4周后,各剂量可显著增加糖水消耗百分比,旷场水平运动距离和垂直运动次数(P<0.05,P<0.01),改善抑郁动物行为学;可升高抑郁模型脑皮层中5-HT、DA以及NE的含量(P<0.05)。结论白金胶囊可改善CUMS致抑郁症大鼠模型的行为学异常,作用机制可能与增加脑皮层中单胺类神经递质含量有关。

五乙酰栀子苷对CUMS大鼠抑郁行为及其对HPA轴的影响

目的建立慢性应激抑郁模型大鼠,观察五乙酰栀子苷对慢性轻度不可预见性应激(CUMS)大鼠抑郁样行为及其对下丘脑-垂体-肾上腺(HPA)轴的影响。方法 60只大鼠随机分为正常组、模型组、五乙酰栀子苷组(25、50、100mg/kg)和氟西汀组(10 mg/kg)。除正常组外,均采用CUMS制备大鼠抑郁模型。从造模第8天开始,五乙酰栀子苷和氟西汀连续灌胃给药2周。糖水偏爱实验、旷场实验及强迫游泳实验检测大鼠行为学,检测血清皮质酮(CORT)、肾上腺指数及下丘脑促肾上腺皮质激素释放激素(CRH)mRNA,探讨五乙酰栀子苷的抗抑郁作用及机制。结果与正常组相比,CUMS大鼠表现出异常行为学及HPA轴活化,五乙酰栀子苷能逆转CUMS诱导的大鼠行为学改变,包括提高糖水消耗量、增加穿格数和站立数、缩短不动时间及延长游泳时间。同时,五乙酰栀子苷能使CUMS大鼠异常的HPA轴功能恢复,包括降低血清CORT和肾上腺指数、抑制下丘脑CRH mRNA表达。结论五乙酰栀子苷可以改善CUMS大鼠行为学,其抗抑郁作用可能与调节HPA轴功能有关。