Hydrogen sulfide attenuates gastric mucosal injury induced by restraint water-immersion stress via activation of KATPchannel and NF-κB dependent pathway

AIMTo explore the effect of hydrogen sulfide (H2S) on restraint water-immersion stress (RWIS)-induced gastric lesions in rats and the influence of adenosine triphosphate (ATP)-sensitive potassium (KATP) channels and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathway on such an effect.METHODSMale Wistar rats were randomly divided into a control group, a physiological saline (PS) group, a sodium hydrosulfide (NaHS) group, a glibenclamide (Gl) group, Gl plus NaHS group, a pyrrolidine dithiocarbamate (PDTC) group, and a PDTC plus NaHS group. Gastric mucosal injury was induced by RWIS for 3 h in rats, and gastric mucosal damage was analyzed after that. The PS, NaHS (100 μmol/kg body weight), Gl (100 μmol/kg body weight), Gl (100 μmol/kg or 150 μmol/kg body weight) plus NaHS (100 μmol/kg body weight), PDTC (100 μmol/kg body weight), and PDTC (100 μmol/kg body weight) plus NaHS (100 μmol/kg body weight) were respectively injected intravenously before RWIS.RESULTSRWIS induced serious gastric lesions in the rats in the PS pretreatment group. The pretreatment of NaHS (a H2S donor) significantly reduced the damage induced by RWIS. The gastric protective effect of the NaHS during RWIS was attenuated by PDTC, an NF-κB inhibitor, and also by glibenclamide, an ATP-sensitive potassium channel blocker, in a dose-dependent manner.CONCLUSIONThese results suggest that exogenous H2S plays a protective role against RWIS injury in rats, possibly through modulation of KATP channel opening and the NF-κB dependent pathway.

Nervous mechanisms of restraint water-immersion stress-induced gastric mucosal lesion

Stress-induced gastric mucosal lesion(SGML)is one of the most common visceral complications after trauma.Exploring the nervous mechanisms of SGML has become a research hotspot.Restraint water-immersion stress(RWIS)can induce GML and has been widely used to elucidate the nervous mechanisms of SGML.It is believed that RWIS-induced GML is mainly caused by the enhanced activity of vagal parasympathetic nerves.Many central nuclei,such as the dorsal motor nucleus of the vagus,nucleus of the solitary tract,supraoptic nucleus and paraventricular nucleus of the hypothalamus,mediodorsal nucleus of the thalamus,central nucleus of the amygdala and medial prefrontal cortex,are involved in the formation of SGML in varying degrees.Neurotransmitters/neuromodulators,such as nitric oxide,hydrogen sulfide,vasoactive intestinal peptide,calcitonin gene-related peptide,substance P,enkephalin,5-hydroxytryptamine,acetylcholine,catecholamine,glutamate,γ-aminobutyric acid,oxytocin and arginine vasopressin,can participate in the regulation of stress.However,inconsistent and even contradictory results have been obtained regarding the actual roles of each nucleus in the nervous mechanism of RWIS-induced GML,such as the involvement of different nuclei with the time of RWIS,the different levels of involvement of the sub-regions of the same nucleus,and the diverse signalling molecules,remain to be further elucidated.

Altered Neuronal Activity in the Central Nucleus of the Amygdala Induced by Restraint Water-Immersion Stress in Rats

Restraint water-immersion stress(RWIS), a compound stress model, has been widely used to induce acute gastric ulceration in rats. A wealth of evidence suggests that the central nucleus of the amygdala(CEA) is a focal region for mediating the biological response to stress. Different stressors induce distinct alterations of neuronal activity in the CEA; however, few studies have reported the characteristics of CEA neuronal activity induced by RWIS. Therefore, we explored this issue using immunohistochemistry and in vivo extracellular single-unit recording. Our results showed that RWIS and restraint stress(RS) differentially changed the c-Fos expression and firing properties of neurons in the medial CEA. In addition,RWIS, but not RS, induced the activation of corticotropinreleasing hormone neurons in the CEA. These findings suggested that specific neuronal activation in the CEA is involved in the formation of RWIS-induced gastric ulcers.This study also provides a possible theoretical explanation for the different gastric dysfunctions induced by different stressors.

A Case of Multiple Hemorrhagic Gastric Ulcers Developed via a Mechanism Similar to Water-Immersion Restraint Stress

In rats, water-immersion restraint stress is a model of experimental ulceration. We encountered a case in which multiple hemorrhagic gastric ulcers formed in the stomach in a setting similar to water-immersion restraint stress. The patient was a 54-year-old man who was found wet on a riverbank and transported by ambulance. Because of hypothermia and renal failure, hemodialysis was performed. Tarry stools were noted and endoscopy revealed the presence of multiple hemorrhagic gastric ulcers;thus, hemostasis was performed end oscopically. During the course, pseudo membranous colitis also developed and was ameliorated with vancomycin. Further, the renal failure and gastric ulcers improved, and the patient was discharged from hospital 25 days later. The reason why he survived more than 2 weeks was the hot summer season and he was not soaked in the river water throughout.

Dip2a regulates stress susceptibility in the basolateral amygdala

Dysregulation of neurotransmitter metabolism in the central nervous system contributes to mood disorders such as depression, anxiety, and post–traumatic stress disorder. Monoamines and amino acids are important types of neurotransmitters. Our previous results have shown that disco-interacting protein 2 homolog A(Dip2a) knockout mice exhibit brain development disorders and abnormal amino acid metabolism in serum. This suggests that DIP2A is involved in the metabolism of amino acid–associated neurotransmitters. Therefore, we performed targeted neurotransmitter metabolomics analysis and found that Dip2a deficiency caused abnormal metabolism of tryptophan and thyroxine in the basolateral amygdala and medial prefrontal cortex. In addition, acute restraint stress induced a decrease in 5-hydroxytryptamine in the basolateral amygdala. Additionally, Dip2a was abundantly expressed in excitatory neurons of the basolateral amygdala, and deletion of Dip2a in these neurons resulted in hopelessness-like behavior in the tail suspension test. Altogether, these findings demonstrate that DIP2A in the basolateral amygdala may be involved in the regulation of stress susceptibility. This provides critical evidence implicating a role of DIP2A in affective disorders.

Correlation between changes of central neurotransmitter expression and stress response in mice A restraint time-course analysis

BACKGROUND： Changes in central neurotransmitter expression play an important role in stress response and forms the basis for stress-induced psychological and behavior changes. OBJECTIVE： To observe the effects of different restraint stress intervals on brain monoamine neurotransmitter expression, and to investigate the correlation between stress response and neurotransmitter levels. DESIGN： Randomized controlled animal study. SETTING： Chinese Herb and Natural Medicine Institute, Pharmacological College of Jinan University. MATERIALS： Sixty 7-week-old male Kunming mice of clean grade, weighing 18-22 g, were provided by the Guangdong Medical Experimental Animal Center. The experiment was in accordance with animal ethics standards. METHODS： This study was performed at the Chinese Herb and Natural Medicine Institute, Pharmacological College of Jinan University from June 2006 to May 2007. A restraint device for mice was constructed according to published reports. Experimental mice were adaptively fed for 1 week and randomly divided into a control group （n = 10） and an experimental group （n = 50）. The experimental group was sub-divided into five restraint intervals： 4, 8, 12, 18, and 24 hours （n = 10 mice per time point）. Animals in the experimental group were not allowed to eat or drink during the restraint period. Mice in the control group did not undergo restraint, but had identical food and water restrictions. Cerebral cortex and hypothalamus were separated based on observational times and protein was extracted using perchloric acid. Central monoamine neurotransmitter levels were measured using high performance liquid chromatography with electrochemical detection. MAIN OUTCOME MEASURES： Levels of norepinephrine （NE）, dopamine hydrochloride （DA）, 3,4-dihydroxyphen-ylanetic acid （DOPAC）, homovanillic acid （HVA）, 5-hydroxytryptamine （5-HT）, and 5-hydroxyindoleac-etic acid （5-HIAA） in the cerebral cortex and hypothalamus of mice. RESULTS： Sixty mice were included in the final analysis. ① NE levels in the cerebral cortex, hypothalamus, and plasma： four hours after restraint, NE levels in the cerebral cortex and hypothalamus ere significantly lower than control levels （P 〈 0.05）. After 12 hours of restraint, NE levels in the experimental group were significantly higher than in the control group （P 〈 0.05）. At 18 hours of restraint, there was no significant difference in NE levels in the cerebral cortex between the experimental group and the control group （P 〉 0.05）. In addition, NE levels in the plasma gradually increased with longer restraint time, which was significant between experimental groups and the control group （P 〈 0.05-0.01）. ② Levels of DA, DOPAC, and HVA in the cerebral cortex and hypothalamus： there were significant differences in DA levels in the cerebral cortex and hypothalamus after 18 and 24 hours of restraint compared to control animals （P 〈 0.05）. DOPAC and HVA levels in the cerebral cortex were enhanced with longer restraint time, and there was significant difference in all restraint groups compared to control levels （P 〈 0.01）, except for DOPAC levels after 4 hours of restraint. Moreover, DOPAC and HVA levels in the hypothalamus were enhanced with increasing restraint time. Levels of 5-HT and 5-HIAA in the cerebral cortex and hypothalamus： after short restraint periods and in the control group, 5-HT was not detectable. However, it was quantitatively detected at 12 hours after restraint. The 5-HT levels in the cerebral cortex and hypothalamus reached peak levels at 12 and 18 hours of restraint. 5-HIAA levels in the cerebral cortex and hypothalamus showed a similar tendency to increase with restraint time- 5-HIAA levels at 4-8 hours after restraint were significantly higher than control levels （P 〈 0.01）. The 5-HIAA levels decreased at 12 hours after restraint, but remained significantly higher than the control group （P 〈 0.05）. CONCLUSION： Restraint stress affects the hypothalamic-pituitary-adrenal （HPA） axis and causes changes in monoamine neurotransmitters in brain tissues, which suggests stress status could be improved by adjusting HPA axis and neurotransmitter levels in the brain.

Effect of restraint stress on depression-like behaviors in rats after transient focal cerebral ischemic injury

BACKGROUND： Restraint stress is a typical psychophysiological stressor. Simulating the early passion and difficulty in walking of patients after attack of stroke meets onset features.OBJECTIVE： To evaluate the effect of restraint stress on depression-like behaviors in rats after transient focal cerebral ischemic injury, and to investigate the feasibility for its being as modeling method of depression model after stroke.DESIGN： A randomized controlled animal experiment.SETTING： Department of Clinical Medicine, Faculty of Aerospace Medicine of the Fourth Military Medical University of Chinese PLA.MATERIALS： Forty-eight male Sprague-Dawley rats, weighing 240 - 270 g, provided by the Experimental Animal Center of the Fourth Military Medical University of Chinese PLA were used in the current study.METHODS： The experiments were carried out in the Faculty of Aerospace Medicine of the Fourth Military Medical University of Chinese PLA between August 2005 and August 2006. ①Experiment intervention： The rats were randomized into middle cerebral artery occlusion-reperfusion （MCAO） ＋stress group, simple MCAO group, sham-operation ＋ stress group and simple sham-operation group, with 12 rats in each group.Rats in the first two groups were developed into cerebral ischemia/reperfusion models by suture-occluded method. Rats in the MCAO＋stress group were modeled and restraint stress scheme was performed. At week 5 after modeling, the rats were placed in self-made restraining tubes, 2 hours/time, once a day, for 2 successive weeks. The common carotid artery, external and internal carotid arteries of rats in the latter two groups were exposed. The stress way of sham-operation＋ stress group was the same as that of MCAO＋ stress group. ②The neurological status grading and motor performance evaluation （screen test, rota-rod test and balance beam test） were conducted in rats with simple sham-operation group and MCAO group before, 1st and 28^th days after modeling. Depression-like behavior test was performed in the rats of each group by sucrose preference test and open field test at the end of the experiment.MAIN OUTCOME MEASURES： Changes of depression-like behaviors of rats in each group.RESULTS： Forty-eight rats were involved in the experiment. Two rats with meningeal irritation sign were excluded from simple MCAO group, and one rat in the MCAO＋stress group died of some unclear causes during the experiments. The other 45 rats entered the stage of finial analysis. ① Depression-like behavior assessment results： The rats in the MCAO＋ stress group had a significantly decreased preference for sucrose solution, crossing and rearing scores, and increased immobility duration after the 14-day restraint stress,compared with those in other three groups （all P〈0.05）. ②The neurological status grading and motor performance evaluation： There were significant differences in the two indexes of rats in the simple MCAO group before, 1^st and 28^th days after modeling （P〈0.01）, while there was no significant difference before and 28^th days after modeling （P〉0.05）. There were no significant changes in sham-operation group at each time point （P〉0.05）.CONCLUSION： After being exerted restraint stress, the rats with transient focal ischemic injury may show obvious depression-like behaviors. Therefore, restraint stress can be used as a novel animal modeling method for further studying biological mechanism in central nervous system of post-stroke depression animals.

Electroacupuncture pretreatment exhibits antidepressive effects by regulating hippocampal proteomics in rats with chronic restraint stress

The clinical effect of electroacupuncture on depression is widely recognized. However, the signal transduction pathways and target proteins involved remain unclear. In the present study, rat models of chronic restraint stress were used to explore the mechanism by which electroacupuncture alleviates depression. Rats were randomly divided into control, model, and electroacupuncture groups. Chronic restraint stress was induced in the model and electroacupuncture groups by restraining rats for 28 days. In the electroacupuncture group, electroacupuncture pretreatment at Baihui（GV20） and Yintang（GV29） acupoints was performed daily（1 m A, 2 Hz, discontinuous wave, 20 minutes） prior to restraint for 28 days. Open field tests and body weight measurements were carried out to evaluate the depressive symptoms at specific time points. On day 28, the crossing number, rearing number, and body weights of the model group were significantly lower than those in the control group. Behavior test results indicated that rat models of depressive-like symptoms were successfully established by chronic restraint stress combined with solitary raising. On day 28, an isobaric tag for a relative and absolute quantitation-based quantitative proteomic approach was performed to identify differentially expressed proteins in hippocampal samples obtained from the model and electroacupuncture groups. The potential function of these differential proteins was predicted through the use of the Cluster of Orthologous Groups of proteins（COG） database. Twenty-seven differential proteins（uncharacteristic proteins expected） were selected from the model and electroacupuncture groups. In addition to unknown protein functions, COG are mainly concentrated in general prediction function, mechanism of signal transduction, amino acid transport and metabolism groups. This suggests that electroacupuncture improved depressive-like symptoms by regulating differential proteins, and most of these related proteins exist in nerve cells.

Antidepressant-like Effects of Ginsenoside Rg1 in the Chronic Restraint Stress-induced Rat Model

Objective To investigate the ameliorating effect of ginsenoside Rg1 on the depression-like behaviors induced by chronic restraint stress(CRS)in rats and the underlying mechanisms.Methods Forty male Wistar rats were divided into 4 groups according to their baseline sucrose preference:control group,model group,and Rg1-treated groups(5 and 10 mg/kg).Except for control group,the groups were exposed to CRS(6 h/day)for 28 days.All drugs were intraperitoneally administered once daily to CRS rats after restraint stress for 14 days.The behavioral tests were carried out via the open field test(OFT),sucrose preference test(SPT),forced swim test(FST),and the Morris water maze(MWM)4 weeks following CRS induction.The levels of serum corticosterone(CORT)and the activities of the antioxidant defense biomarkers(SOD,MDA and GSH-x)in the prefrontal cortex(PFC)were analyzed using commercial ELISA kits.The levels of the neurotransmitter(5-HT,5-HIAA,Ach,NE,GABA and Glu)in the PFC were measured by ultra-performance liquid chromatography tandem mass spectrometry.The protein expression of BDNF,Trkb,Bax and Bcl-2 in the PFC was detected by western blotting.Results Owing to increased sucrose consumption in the SPT,decreased immobility time in the FST,and the improved cognitive performance in MWM,chronic treatment with Ginsenoside Rg1 was found to significantly attenuate depressionlike behaviors(anhedonia,behavioral despair and poor spatial memory)in rats.Moreover,CRS exposure caused evident alterations in the levels of the neurotransmitters(5-HT,5-HIAA,Ach,GABA and Glu)and the activities of the antioxidant defense biomarkers(SOD,MDA and GSH-x)in the PFC and the levels of corticosterone in serum.However,Ginsenoside Rg1 treatment could restore these levels to normal values.Additionally,Ginsenoside Rg1 treatment significantly reverted the decreased expression of BDNF,Trkb and Bcl-2 and the increased expression of Bax in the PFC of CRS rats.Conclusions Ginsenoside Rg1 could attenuate the CRS-induced depression-like behaviors,in part,by regulating neurotransmitter levels and HPA function,antagonizing oxidative stress and apoptosis,and restoring BDNF-TrkB signaling in PFC.Altogether,our results provide a novel basis regarding the potential therapeutic effects of Rg1 on depression.

Interleukin-18 levels in the hippocampus and behavior of adult rat offspring exposed to prenatal restraint stress during early and late pregnancy

Exposure to maternal stress during prenatal life is associated with an increased risk of neuropsychiatric disorders, such as depression and anxiety, in offspring. It has also been increasingly observed that prenatal stress alters the phenotype of offspring via immunological mechanisms and that immunological dysfunction, such as elevated interleukin-18 levels, has been reported in cultures of microglia. Prenatal restraint stress(PRS) in rats permits direct experimental investigation of the link between prenatal stress and adverse outcomes. However, the majority of studies have focused on the consequences of PRS delivered in the second half of pregnancy, while the effects of early prenatal stress have rarely been examined. Therefore, pregnant rats were subjected to PRS during early/middle and late gestation(days 8–14 and 15–21, respectively). PRS comprised restraint in a round plastic transparent cylinder under bright light(6500 lx) three times per day for 45 minutes. Differences in interleukin-18 expression in the hippocampus and in behavior were compared between offspring rats and control rats on postnatal day 75. We found that adult male offspring exposed to PRS during their late prenatal periods had higher levels of anxiety-related behavior and depression than control rats, and both male and female offspring exhibited higher levels of depression-related behavior, impaired recognition memory and diminished exploration of novel objects. Moreover, an elevated level of interleukin-18 was observed in the dorsal and ventral hippocampus of male and female early-and late-PRS offspring rats. The results indicate that PRS can cause anxiety and depression-related behaviors in adult offspring and affect the expression of interleukin-18 in the hippocampus. Thus, behavior and the molecular biology of the brain are affected by the timing of PRS exposure and the sex of the offspring. All experiments were approved by the Animal Experimentation Ethics Committee at Kunming Medical University, China(approval No. KMMU2019074) in January 2019.

Inhibition of T Cell and Stimulation of B Cell Proliferation by Restraint Stress Mediated by Voltage-Gated Potassium Channel 1.3 Expression

Our previous study has showed that restraint stress inhibits T cell proliferation. Kv1.3 plays a key role in the lymphocyte activation process. Here, we investigate the effects of restraint stress on murine splenic T and B cell proliferation and the role of Kv1.3 in the process. 3H-TdR incorporation is used to determine changes in splenocyte proliferation stimulated by Con A or LPS between control and restraint stress groups. The data shows that restraint stress inhibits T cell and enhanced B cell proliferation. Data from RT-PCR and Western blotting shows that Kv1.3 gene and protein levels are downregulated in T cells and upregulated in B cells in stressed mice. To examine a possible cause-and-effect relationship between Kv1.3 and stress-affected lymphocyte proliferation, we employ various Kv1.3 specific blockers (quinine, 4-AP and TEA) to determine K+ channel function under restraint stress. The data shows that Kv1.3 blockers reverse the decreased T cell proliferation and increase B cell proliferation induced by restraint stress. These results indicate that Kv1.3 mediates restraint stress-induced modulation of T/B lymphocyte proliferation.

Retigabine alleviates chronic restraint stress -induced memory retrieval impairment in male mice

Aim To investigate whether Kv7 channels opener retigabine could alleviate memory impairment induced by chronic restraint stress （CRS） and the underlying neuroprotective mechanisms. Methods Adult male Kunming （KM） mice, weighing 20 - 25 g, were restrained in well-ventilated Plexiglass tubes for 6 h daily beginning from 10 ： 00 to 16 ： 00 for 21 consecutive days. Mice were injected with retigabine （ 10 mg · kg^-1） or vehicle （ 10% DM- SO） 30 rain before restraint stress for 21 days. After stressor cessation, the spatial learning and memory was deter- mined by Morris water maze test, the levels of p-Akt, p-GSK-3β and p-Erkl/2 of hippocampal tissues were exam- ined by western blot. Results Compared with control group, CRS mice exhibited significantly longer escape laten- cies on day 2, 3 and 4 （P 〈 0.05, P 〈 0. 01, P 〈 0.01 ） respectively, but retigabine （ 10 mg · kg^-1） treatment had no influences on escape latencies compared with CRS group. During the probe test, CRS mice spent significant less time in target quadrant than control group （P 〈 0.01 ）. Compared with CRS group, retigabine （ 10 mg · kg^-1 ） treatment increased the time spent in target quadrant （P 〈 0.01 ）. Additionally, the swimming speed showed no significant differences among groups. Western blot results showed that the levels of p-Akt, p-GSK-3β and p-Erkl/ 2 in the hippocampus of CRS mice were significantly decreased compared with control group. Compared with CRS group, retigabine （ 10 mg· kg^-1） treatment strongly prevented the reduction of p-Akt and p-GSK-3 β （P 〈 0.01 ）, but had no effect on the reduction of p-Erkl/2. Conclusion Retigabine protected against CRS-induced spatial memory retrieval impairment partly via activation of Akt/GSK-3β signaling pathway.

Restraint-Induced Expression of Endoplasmic Reticulum Stress-Related Genes in the Mouse Brain

Depression is a significant public health concern but its pathology remains unclear. Previously, increases in an endoplasmic reticulum (ER) stress-related protein were reported in the temporal cortex of subjects with major depressive disorder who had died by suicide. This finding suggests an association between depression and ER stress. The present study was designed to investigate whether acute stress could affect the ER stress response. Mice were immobilized for a period of 6 hr and then expression of ER stress response-related genes was measured by real-time PCR. We also used enzyme-linked immunosorbent assay for concomitant measurement of the plasma corticosterone levels in the mice. The effect of corticosterone on ER stress proteins was further investigated by treating mice with corticosterone for 2 weeks and then measuring ER protein expression by Western blotting. After a 6 hr restraint stress, mRNA levels of ER stress-related genes, such as the 78-kilodalton glucose regulated protein (GRP78), the 94-kilodalton glucose regulated protein (GRP94), and calreticulin, were increased in the cortex, hippocampus, and striatum of mouse brain. Blood plasma corticosterone level was also increased. In the corticosterone-treated mouse model, the expression of GRP78 and GRP94 was significantly increased in the hippocampus. These results suggest that acute stress may affect ER function and that ER stress may be involved in the pathogenesis of restraint stress, including the development of depression.

Chronic restraint stress impairs ischemia-induced neovascularization through DPP-4-dependent pathway

Background and Objective The morbidity of lower extremity atherosclerotic disease(LEAD)has increased year by year.Chronic stress attenuates the ability of angiogenesis and deteriorates the prognosis of LEAD.Chronic stress increases plasma and tissue DPP-4 activities in mice.DPP-4 plays an important role in angiogenesis.Therefore,we hypothesized that chronic stress exerted its cardiovascular effects by increasing DPP-4 activation.We investigated the role of DPP-4/GLP-1 axis in ischemiainduced neovascularization in mice under restraint stress.

4T1乳腺癌细胞株接种联合慢性束缚应激诱导乳腺癌合并抑郁小鼠模型构建探索

目的研究4T1乳腺癌细胞株接种联合慢性束缚应激方法构建乳腺癌合并抑郁症小鼠模型核心行为症状、生物学指标、病理学等改变。方法BABL/c小鼠随机分为正常(Control)组、束缚(Stress)组、移植瘤(Tumor)组和束缚移植瘤(Stress+Tumor,S+T)组,将4T1细胞株接种于Tumor和S+T组小鼠腋下,待成瘤后,给予Stress和S+T组小鼠束缚应激21 d。造模期间监测各组小鼠体重、摄食量。实验结束后,采用糖水偏好、旷场、高架十字迷宫、强迫游泳等试验评价各组小鼠抑郁样行为。小鼠处死后,测量小鼠瘤体重量和体积;采用ELISA方法检测各组小鼠血清肿瘤标志物糖类抗原(CA199)、癌胚抗原(CEA)、血管内皮生长因子(VEGF)以及相关神经递质5-羟色胺(5-HT)、去甲肾上腺素(NE)、皮质酮(CORT)的含量;运用HE染色法观察小鼠肿瘤和海马组织病理学改变。结果S+T组小鼠体重、摄食量显著降低,瘤体重量和体积明显增大,血清肿瘤标志物(CA199、CEA、VEGF)水平显著升高,快感和对新环境的探索欲望减弱,紧张和绝望行为显著增强,血清神经递质5-HT和NE水平显著降低,CORT水平显著升高;另外肿瘤组织细胞排列松散,间质减少,病理性核分裂象增多,海马CA3区神经元细胞排列和形态紊乱,核内空泡化样改变明显。结论4T1乳腺癌细胞株接种联合慢性束缚应激诱导的乳腺癌合并抑郁小鼠模型出现了乳腺癌和抑郁症双重典型症状和生物学指标改变,可为乳腺癌合并抑郁实验研究提供较好的模型参考。

基于TGF-β1/CD147信号探讨慢性束缚应激促小鼠乳腺癌进展及逍遥散调节机制研究

目的基于TGF-β1/CD147信号探讨慢性束缚应激促小鼠乳腺癌进展及逍遥散调节机制。方法40只BABL/c小鼠随机分为移植瘤组(Tumor)、模型组(Model)、逍遥散组(Xiaoyaosan)和米非司酮组(Mifepristone),将4T1细胞株接种于各组小鼠腋下,待成瘤后,除Tumor组外其余各组小鼠均进行慢性束缚应激21天,同时Xiaoyaosan组和Mifepristone组小鼠给予相对应的药物灌胃,Tumor组和Model组小鼠灌胃生理盐水。造模结束后,小鼠麻醉断头处死,测量小鼠瘤体重量和体积、内脏指数;采用ELISA方法检测各组小鼠血清肿瘤标志物糖类抗原ca199(Carbohydrate antigen199,CA199)、癌胚抗原(Carcino-embryonic antigen,CEA)、血管内皮生长因子(Vascular endothelial growth factor,VEGF)的含量,血清多巴胺(Dopamine,DA)和皮质酮(Corticosterone,CORT)的含量,以及肿瘤组织转化生长因子β1(Transforming growth factor-β1,TGF-β1)和白介素10(Interleukin 10,IL-10)的含量。采用免疫组化和Western blot方法检测各组小鼠肿瘤组织巨噬细胞极化标志物诱导型一氧化氮合酶(Inducible nitric oxide synthase,iNOS)和精氨酸酶1(Arginase-1,Arg-1)的表达,以及肿瘤组织中细胞外基质金属蛋白酶诱导剂(Extracellular matrix metalloproteinase inducer,EMMPRIN,CD147)及其下游信号分子基质金属蛋白酶2(Matrix metalloproteinases 2),MMP2、基质金属蛋白酶9(MMP9)和VEGF的表达。结果与Tumor组比较,Model组小鼠肿瘤重量和体积,血清CA199、CEA、VEGF、CORT含量,肿瘤TGF-β1和IL-10含量均显著增加;内脏指数和血清DA含量显著减少;肿瘤巨噬细胞M2型极化标志物Arg-1的表达显著增加,M1型极化标志物iNOS的表达显著降低;肿瘤CD147及其下游信号分子MMP2、MMP9和VEGF蛋白表达显著增加,逍遥散和米非司酮均可有效逆转以上改变。结论慢性束缚应激促小鼠乳腺癌进展的机制与肿瘤相关巨噬细胞M2型极化释放TGF-β1增加、激活CD147及其下游相关信号有关,而逍遥散可缓解应激条件下皮质酮增高引起的巨噬细胞M2型极化,减少TGF-β1的生成,抑制CD147及其下游信号,从而抑制慢性应激引起的小鼠乳腺癌进展。

束缚应激致高脂血症ApoE^(-/-)小鼠心肌损伤的分子靶标筛选与机制分析

目的采用蛋白质组学技术筛选慢性束缚应激致高脂血症小鼠心肌损伤的标志物及其潜在机制。方法通过束缚ApoE-/-小鼠建立高脂血症合并慢性应激模型,运用蛋白质组学与生物信息学等技术描绘慢性应激对高脂血症小鼠心肌损伤的特征性分子改变及相关调控机制,并从中探索潜在的诊断标志物。结果蛋白质组学分析结果显示,与高脂血症组相比,高脂血症合并束缚应激组小鼠共有43个显著上调与58个显著下调的差异表达蛋白质。其中,GBP2、TAOK3、TFR1、UCP1是极具诊断潜力的分子标志物。KEGG通路富集分析结果表明,铁死亡是加剧高脂血症合并束缚应激模型心肌损伤的重要机制通路。mmu_circ_0001567/miR-7a/Tfr-1和mmu_circ_0001042/miR-7a/Tfr-1可能是该模型中与铁死亡相关的重要circRNA-miRNA-mRNA调控网络。结论慢性束缚应激可能通过铁死亡加剧高脂血症小鼠的心肌损伤,本研究筛选出4个具有潜在应用价值的心肌损伤分子诊断标志物,为高脂血症合并应激致心脏性猝死的研究提供了新的方向。

姜黄素通过抑制JNK介导的炎症缓解慢性束缚应激诱导的大鼠心脏功能障碍

目的:探讨姜黄素对慢性束缚应激抑郁模型大鼠心功能障碍的影响。方法:将32只重(200±20)g的6周龄雄性Wister大鼠分为对照组、模型组、低剂量姜黄素组和高剂量姜黄素组,每组8只。模型组和给药组大鼠每天随机时段给予慢性束缚应激5 h,对照组大鼠正常条件饲养;在每天的应激结束后,低、高剂量姜黄素组大鼠分别给予100和200 mg/kg的姜黄素灌胃,对照组和模型组大鼠则给予等体积的生理盐水。上述实验操作均连续28 d。实验期间每周称量一次体重;在第14和28天进行蔗糖偏好实验和测量血清皮质酮含量来评价大鼠的抑郁状况;HE和Masson染色法观察心肌组织学变化;超声心动图检查各组大鼠心脏功能;RT-qPCR检测炎症因子和纤维化因子的mRNA表达;Western blot检测相关蛋白的表达。结果:与对照组相比,模型组大鼠体重增长显著减缓(P<0.05),蔗糖偏好率显著降低(P<0.01),血浆皮质酮水平显著升高(P<0.01);HE染色结果显示,与对照组相比,模型组大鼠心肌细胞肥大;Masson染色发现,模型组大鼠心脏纤维化显著高于对照组(P<0.01);免疫组化结果也表明,I型胶原阳性表达显著增加(P<0.01);RT-qPCR结果显示,与对照组相比,模型组大鼠心肌组织中炎症因子(肿瘤坏死因子α、白细胞介素6和白细胞介素1β)和纤维化因子(α-平滑肌肌动蛋白、I型胶原和III型胶原)表达水平均显著升高(P<0.05或P<0.01);Western blot结果显示,与对照组相比,模型组大鼠心肌组织中c-Jun氨基末端激酶(JNK)蛋白的磷酸化水平显著升高(P<0.01)。与模型组相比,低、高剂量姜黄素均可逆转上述指标。结论:姜黄素能抑制慢性束缚应激大鼠的心脏炎症和纤维化,其机制可能是通过抑制JNK信号通路实现的。

岩体地基抗剪刚度系数试验研究

地基抗剪刚度系数反映了地基对上部结构在水平方向的约束强弱程度,直接影响地基上浇筑的混凝土结构温度约束应力的大小,是控制混凝土底板温度裂缝的关键参数之一。为完善温度约束应力计算中地基抗剪刚度系数的取值,基于岩体地基防水层底板温度应力监测现场试验,计算得到岩体地基防水层构造条件下地基抗剪刚度系数取值;而后进行了岩体地基上的防水层、垫层、滑动层3种构造条件的动力特性测试试验,基于量纲分析计算出了垫层和滑动层构造条件下的地基抗剪刚度系数取值。

慢性束缚应激对小鼠小肠屏障的损伤研究

肠屏障由机械屏障、免疫屏障、化学屏障和生物屏障共同组成,在维持肠腔内环境稳态和肠上皮结构完整性等方面发挥重要作用.首先建构小鼠慢性束缚应激模型并进行血浆激素水平检测和小鼠旷场实验,验证模型是否建构成功.随后通过常规组织学染色、免疫组化、 TUNEL免疫荧光、 ELISA等方法研究慢性束缚应激对小鼠小肠的损伤作用.结果显示,慢性束缚应激显著提高小鼠血浆NE和CORT水平(p<0.05),降低小鼠小肠绒毛高度(V,p<0.05)、增加隐窝深度(C,p<0.05),降低V/C比值(p<0.05)及紧密连接蛋白ZO-1表达量(p<0.01);显著减少小肠杯状细胞和内皮单核淋巴细胞数量(p<0.01),提示慢性束缚应激造成了小鼠肠道损伤和免疫功能抑制.进一步研究发现,慢性应激小鼠肠道内PCNA阳性表达显著减少(p<0.01)、凋亡细胞显著增多(p<0.01);血浆中TNF-α,IL-1β,IL-18含量显著升高(p<0.01),而IL-10显著降低(p<0.01).血浆氧化-抗氧化指标结果显示,慢性束缚应激显著增加小鼠血浆MDA含量(p<0.05),降低T-AOC,SOD,CAT,GSH-Px(p<0.05)活性,提示慢性束缚应激诱导机体氧化应激.该研究表明慢性束缚应激通过引发机体氧化应激,造成肠上皮细胞更新抑制和肠道屏障结构损伤,加重机体炎症反应.