Involvement of mTOR‐related signaling in antidepressant effects of Sophoraflavanone G on chronically stressed mice

SophoraflavanoneG (SG), an important prenylated flavonoid isolated from Sophoraalopecuroides.L, is effective for many illnesses. The present study was designed to investigate whether the compound could reverse depressive‐like symptoms and investigate its possible mechanisms. Chronic Unpredictable Mild Stress (CUMS) mice were treated with fluoxetine and SG. The immobility time in forced swimming test (FST) and tail suspension test (TST) were recorded. The levels of pro‐inflammatory cytokines and neurotransmitters in the hippocampus were evaluated. Furthermore, the protein expressions of PI3K, AKT, mTOR, p70S6K, BDNF, and Trkb in hippocampus were detected. Rapamycin, the selective mTOR inhibitor, was used to estimate the potential mechanism. As a result, after 7 days of SG treatment, the immobility time in FST and TST was declined obviously. The levels of IL‐6, IL‐1β, and TNF‐α in the hippocampus were significantly reduced, and the quantity of 5‐HT and NE was raised considerably in SG‐treated group compared with the CUMS‐exposed group. Additionally, SG could up‐regulate the expressions of PI3K, AKT, mTOR, 70S6K, BDNF, and Trkb. The blockade of mammalian target of rapamycin signaling blunted the antidepressant effect and reversed the up‐regulation of BDNF expression caused by SG. These findings suggested that SG treatment alleviated depressive‐like symptoms via mTOR‐mediated BDNF/Trkb signaling.     

Brain‐derived Neurotrophic Factor Signaling Mediates the Antidepressant‐like Effect of the Total Flavonoids of Alpiniae Oxyphyllae Fructus in Chronic Unpredictable Mild Stress Mice

The present study verified the antidepressant‐like effects of the total flavonoids of Alpinia oxyphylla Miq. (AOF) using the chronic unpredictable mild stresses paradigm and explored the mechanism that underlies antidepressant‐like effects of AOF in mice. Previous research has shown that tropomyosin‐related kinase B (TrkB) receptor‐mediated extracellular regulated protein kinases (ERK) signaling pathways participate in depression pathophysiology. Therefore, we aimed to explore whether AOF improved depression‐like behaviors by increasing activity of ERK pathways mediated by TrkB. Results showed that AOF significantly reduced the immobility time in the forced swimming test and increased the sucrose preference in sucrose preference test. In addition, decreased phosphorylated cyclic adenosine monophosphate response element‐binding protein (pCREB)/CREB, pERK/ERK, and pTrkB/TrkB levels in the hippocampus induced by chronic unpredictable mild stresses were reversed by intragastric administration of AOF. Results suggested that AOF increased pCREB/CREB, pERK/ERK, and pTrkB/TrkB levels by acting on the TrkB receptor. To verify this hypothesis, mice were pretreated with the TrkB inhibitor K252a (or 0.1% dimethyl sulfoxide, intraperitoneally, 2 weeks), before the intragastric administration of AOF. This resulted in an absence of antidepressant‐like effects, as well as no activation of pERK/pCREB/BDNF signaling pathways. Results demonstrated that AOF might exert antidepressant‐like effects by targeting TrkB receptor‐mediated pERK/pCREB/BDNF signal systems, which could help to identify the AOF receptor. Copyright © 2016 John Wiley & Sons, Ltd.     

Antidepressant‐like effects of 20(S)‐protopanaxadiol in a mouse model of chronic social defeat stress and the related mechanisms

20(S)‐Protopanaxadiol (PPD) is a basic aglycone of the dammarane triterpenoid saponins and exerts antidepressant‐like effects on behaviour in the forced swimming test (FST) and tail suspension test (TST) and in rat olfactory bulbectomy depression models. However, the antidepressant effects of PPD have not been studied thoroughly. The objective of the present study was first to investigate the effect of PPD on depression behaviours induced by chronic social defeat stress (CSDS) in mice. The results showed that CSDS was effective in producing depression‐like behaviours in mice, as indicated by decreased responses in the social interaction test, sucrose preference test, TST, and FST, and that this effect was accompanied by noticeable alterations in the levels of oxidative markers (superoxide dismutase, catalase, and lipid peroxidation) and monoamines (5‐HT and NE) in the hippocampus and serum corticosterone levels. Additionally, western blot analysis revealed that CSDS exposure significantly downregulated BDNF, p‐TrkB/TrkB, p‐Akt/Akt, and p‐mTOR/mTOR protein expression in the hippocampus. Remarkably, chronic PPD treatment significantly ameliorated these behavioral and biochemical alterations associated withCSDS‐induced depression. Our results suggest that PPD exerts antidepressant‐like effects in mice with CSDS‐induced depression and that this effect may be mediated by the normalization of neurotransmitter and corticosterone levels and the alleviation of oxidative stress, as well as the enhancement of the PI3K/Akt/mTOR‐mediated BDNF/TrkB pathway.     

Retracted: Ganoderic Acid A exerts the cytoprotection against hypoxia‐triggered impairment in PC12 cells via elevating microRNA‐153

Ganoderic Acid A (GAA) is often applied for healing cardiovascular and cerebrovascular ailments, but the influences in cerebral ischemia injury are still hazy. The research delved into the functions of GAA in hypoxia‐triggered impairment in PC12 cells. PC12 cells received hypoxia management for 12 hr, and subsequently, cell viability, migration, apoptosis, and correlative protein levels were assessed. After preprocessing with GAA, above cell behaviors were monitored again. The vector of microRNA (miR)‐153 inhibitor was utilized for PC12 cell transfection to further explore the functions of miR‐153 in hypoxia‐impaired cells. Pathways of phosphatidylinositol 3‐kinase (PI3K)/protein kinase B (AKT) and mammalian target of rapamycin (mTOR) were investigated via executing western blot for uncovering the latent mechanism. Results revealed that hypoxia disposition triggered PC12 cells impairment via restraining cell viability and migration and accelerating apoptosis. However, GAA visibly mollified hypoxia‐provoked impairment in PC12 cells. Interestingly, the enhancement of miR‐153 triggered by GAA was observed in hypoxia‐impaired PC12 cells. After miR‐153 inhibitor transfection, the protective functions of GAA in hypoxia‐impaired PC12 cells were dramatically inversed. Furthermore, GAA caused PI3K/AKT and mTOR activations via enhancement of miR‐153 in hypoxia‐impaired PC12 cells. The findings evinced that GAA exhibited the protective functions in PC12 cells against hypoxia‐evoked impairment through activating PI3K/AKT and mTOR via elevating miR‐153.     

逍遥散抗抑郁作用的BDNF/CREB信号机制

目的:探讨逍遥散抗抑郁作用的BDNF/CREB信号机制。方法:采用小鼠慢性温和不可预知应激(CUMS)结合孤养抑郁模型,逍遥散水煎液30g/kg灌胃给药4周,测定小鼠体重、自主活动及糖水消耗量的变化以评价药物的抗抑郁效应。ELISA法测定血清BDNF水平,实时荧光定量聚合酶链式反应(real-time PCR)测定小鼠海马及皮质部位CREB、BDNF mRNA表达,Western-blot方法测定小鼠脑内ERK1/2及磷酸化ERK1/2(pERK1/2)的蛋白表达量。结果:与模型组比较,逍遥散30g/kg能提高模型小鼠体重、自主活动及糖水消耗量,并有提高模型动物血清BDNF含量的趋势;逍遥散30g/kg显著增加模型小鼠海马BDNF、CREB mR-NA及皮质BDNF mRNA的表达量,对模型动物海马部位pERK1/2的表达量有提高趋势。结论:逍遥散对CUMS结合孤养的小鼠抑郁模型具有抗抑郁效应,作用机制与干预BDNF/CREB信号途径的关键分子的表达与功能有关。     

逍遥散对CUMS大鼠海马CA1区PI3K/AKT信号通路的调节作用研究

目的：本研究旨在探讨逍遥散通过调节PI3K/AKT信号通路进而改善由谷氨酸引起的兴奋性损伤的机制。 方法：100只雄性SD大鼠随机分为正常组、模型组、逍遥散组和氟西汀组,利用CUMS方法造模成为抑郁模型大鼠,上述组别分别予以双蒸水、双蒸水、逍遥散药液、氟西汀溶液连续灌胃3周,后进行行为学观察及相关指标检测。采用旷场试验(OFT)和蔗糖偏好试验(SPT)评价逍遥散的抗抑郁作用;ELISA法测定海马组织中5-HT、NE水平;比色法检测各组大鼠海马CA1区谷氨酸水平; RT-qPCR检测海马CA1区NR2B、PI3K的mRNA水平;western blot检测海马CA1区NR2B、PI3K、P-AKT、Akt的蛋白表达。 结果：逍遥散的体内干预可显著提高抑郁大鼠海马组织中的5-HT、NE水平、降低海马CA1区谷氨酸水平、增加了海马CA1区NR2B、PI3K及P-AKT/AKT比值,显著改善了大鼠的抑郁症状。 结论:逍遥散可显著改善经慢性应激刺激后大鼠的抑郁样行为,其机制可能与降低谷氨酸兴奋性毒性,从而提高PI3K/Akt信号通路活性有关。     

Retracted: Ganoderic acid A alleviates hypoxia‐induced apoptosis,autophagy, and inflammation in rat neural stem cells through the PI3K/AKT/mTOR pathways

Effects of ganoderic acid A (GAA), a lanostane triterpene, on hypoxia‐ischemia encephalopathy (HIE) remain unclear. We aimed to figure out the specific role of GAA in hypoxia‐treated neural stem cells (NSCs) as well as the regulatory mechanisms. Primary rat NSCs were incubated under hypoxia to simulate HIE. Viability and apoptosis of hypoxia‐injured NSCs were measured by cell counting kit‐8 and flow cytometry assays, respectively. Proteins related to apoptosis, autophagy, and the PI3K/AKT/mTOR pathways were evaluated by Western blot analysis. LY294002 and rapamycin were added to inhibit the PI3K/AKT pathway and mTOR pathway, respectively. Enzyme‐linked immunosorbent assay was carried out to test the release of proinflammatory cytokines. We found that hypoxia‐induced decrease of cell viability, increases of apoptotic cells and autophagy, and the release of IL‐6, IL‐1β, and TNF‐α were all attenuated by GAA stimulation. Activation of caspases induced by hypoxia was alleviated by GAA. Furthermore, we found that inhibition of the PI3K/AKT pathway eliminated the effects of GAA on apoptosis and proinflammatory cytokines release in hypoxia‐injured NSCs. Meanwhile, inhibition of the mTOR pathway abrogated the effects of GAA on cell autophagy in hypoxia‐injured NSCs. In conclusion, GAA alleviated hypoxia‐induced injury in NSCs might be through activating the PI3K/AKT and mTOR pathways.     

Bushenhuoxue improves cognitive function and activates brain-derived neurotrophic factor-mediated signaling in a rat model of vascular dementia

OBJECTIVE: To explore the protective mechanisms of the Traditional Chinese Medicine Bushenhuoxue(BSHX) in a rat model of vascular dementia(VD).METHODS: A rat model of VD was developed using bilateral common carotid artery occlusion(BCCAO).Rats were administered BSHX(10.14 or 5.07 g/kg),nimodipine(11.06 mg/kg; positive control), or saline(control) by gavage daily for 30 d post-surgery.Learning and memory abilities were assessed using the Morris water maze. Morphological changes in the hippocampus were observed using light microscopy(hematoxylin and eosin staining) and transmission electron microscopy(TEM). The m RNA and protein expression levels of brain-derived neurotrophic factor(BDNF), tyrosine receptor kinase B(Trk B), phosphatidyl inositol 3-kinase(PI3 K), serine/threonine kinase(AKT), and c AMP response element binding protein(CREB) were measured by real-time polymerase chain reaction(RT-PCR) and Western blot, respectively.RESULTS: Compared with the sham group, rats with BCCAO exhibited impaired learning and memory abilities(Morris water maze) and showed abnormalities in neuronal morphology(light microscopy)and ultrastructure(TEM) in the hippocampus. They also had decreased m RNA and protein expressions of BDNF, Trk B, PI3 K, AKT, and CREB in hippocampal tissue(all P 0.05). In rats with BCCAO, administration of BSHX attenuated deficits in learning and memory, improved the morphology and ultrastructure of hippocampal neurons, and enhanced m RNA and protein expression levels of BDNF, Trk B, PI3 K,AKT, and CREB(all P 0.05).CONCLUSION: BSHX may protect hippocampal neurons and improve learning and memory abilities, at least in part via the activation of BDNF/Trk B/PI3 K/AKT/CREB signaling.     

Imperatorin ameliorates learning and memory deficits through BDNF/TrkB and ERK/CaMKIIα/CREB signaling in prenatally‐stressed female offspring

Prenatal stress (PS) can lead to impaired spatial learning and memory in offspring. Imperatorin (IMP) is a naturally occurring furanocoumarin with many pharmacological properties. However, the effects of IMP on cognitive impairment induced by PS and the underlying molecular mechanisms remain unclear. We investigated the protective effect of IMP treatment after PS on learning and memory deficits in female offspring at postnatal 60 days. After treating prenatally‐stressed offspring with IMP (15 and 30 mg/kg) for 28 days, we found that IMP increased body weight and ameliorated spatial learning and memory and working memory deficits in female offspring rats. Meanwhile, hippocampal Glu and serum corticosterone levels in prenatally‐stressed offspring were significantly decreased after IMP administration. Additionally, IMP treatment significantly increased BDNF, TrkB, CaMKII, and CREB mRNA expression in the hippocampus of offspring rats. Furthermore, PS‐mediated induction of RKIP protein and mRNA expression and glucocorticoid receptor protein expression in the hippocampus of offspring rats were significantly decreased by IMP treatment, and the protein expression of BDNF and TrkB and relative levels of p‐EKR/ERK, p‐CaMKIIα/CaMKIIα, and p‐CREB/CREB were remarkably increased after IMP treatment. Taken together, IMP can ameliorate PS‐induced learning and memory deficits through BDNF/TrkB and ERK/CaMKIIα/CREB signaling pathway and hypothalamic–pituitary–adrenal axis.     

基于BDNF/TrkB/PI3K/Akt信号通路的滋肾醒脑汤对阿尔茨海默病大鼠学习记忆能力的影响

目的基于BDNF/TrkB/PI3K/Akt信号通路观察滋肾醒脑汤对阿尔茨海默病(AD)大鼠学习记忆能力的影响,探讨其可能的作用机制。方法采用侧脑室注射β-淀粉样蛋白制备AD大鼠模型,假手术组注射等体积生理盐水,将成模大鼠随机分为模型组、中药组及阳性对照组,每组6只,中药组及阳性对照组分别予滋肾醒脑汤(16.74 g/kg)和盐酸多奈哌齐混悬液(0.45 mg/kg)灌胃,假手术组和模型组灌胃等体积蒸馏水,每日1次,连续4周。采用Morris水迷宫实验进行大鼠行为学检测,TUNEL染色检测海马组织神经细胞凋亡情况,Western blot检测海马组织脑源性神经营养因子(BDNF)、酪氨酸激酶受体B(TrkB)蛋白表达,免疫组化检测海马组织PI3K、Akt蛋白表达。结果与假手术组比较,模型组大鼠逃避潜伏期明显延长,跨越平台次数减少,目标象限停留时间缩短(P<0.05,P<0.01),海马组织神经细胞凋亡率明显升高,BDNF、TrkB、PI3K、Akt蛋白表达明显降低(P<0.05);与模型组比较,中药组及阳性对照组大鼠逃避潜伏期明显缩短,跨越平台次数增加,目标象限停留时间延长(P<0.01,P<0.05),海马组织神经细胞凋亡率明显降低,BDNF、TrkB、PI3K、Akt蛋白表达明显升高(P<0.05,P<0.01),中药组与阳性对照组差异无统计学意义(P>0.05)。结论滋肾醒脑汤可改善AD大鼠学习记忆能力,其机制可能与上调BDNF/TrkB/PI3K/Akt信号通路蛋白表达,减少神经细胞凋亡有关。     

乌索酸调节PI3K/AKT/mTOR信号通路在结直肠癌中的研究进展

乌索酸（Ursolic acid,UA）是一种广泛存在于植物的草、叶、花和果实中的具有抗氧化,抗菌,抗炎,肝保护,免疫调节,抗肿瘤,化学预防,心脏保护、抗高脂血症和降低血糖等活性的五环三萜类化合物。本文综述了乌索酸结构与抗肿瘤机制、PI3K/AKT/mTOR信号通路参与结直肠癌进程以及乌索酸调节PI3K/AKT信号通路阻碍结直肠癌进展。     

6-Methoxydihydrosanguinarine induces apoptosis and autophagy in breast cancer MCF-7 cells by accumulating ROS to suppress the PI3K/AKT/mTOR signaling pathway

6-Methoxydihydrosanguinarine (6-MDS) is a natural benzophenanthridine alkaloid extracted from Hylomecon japonica (Thunb.) Prantl. It is the first time to explore the effect and mechanism of 6-MDS in breast cancer. Network pharmacology, molecular docking, and molecular dynamics simulation technology were adopted to identify the potential targets and pathways of 6-MDS in breast cancer. Besides, cell proliferation, apoptosis, and western blotting assays were conducted to investigate the effect of 6-MDS on MCF-7 cells. Network pharmacology, molecular docking, and molecular dynamics simulation results confirmed the effect of 6-MDS on resisting breast cancer via the PI3K/AKT/mTOR signaling pathway. In addition, the functional experiments results demonstrated that 6-MDS inhibited proliferation and induced apoptosis and autophagy. The autophagy inhibitor chloroquine and the silence of Atg5 augmented the effect of 6-MDS on promoting apoptosis. Furthermore, 6-MDS suppressed the PI3K/AKT/mTOR signaling pathway, and the PI3K inhibitor LY294002 enhanced these changes and promoted the 6-MDS pro-apoptotic and autophagy effects. 6-MDS triggered the generation of reactive oxygen species. The pretreatment with antioxidant N-acetyl-L-cysteine reversed the changes induced by 6-MDS, including increases in apoptosis and autophagy and inhibition of the PI3K/AKT/mTOR pathway. In conclusion, 6-MDS induces the apoptosis and autophagy of MCF-7 cells by ROS accumulation to suppress the PI3K/AKT/mTOR signaling pathway.     

Rapid antidepressant‐like effect of Fructus Aurantii depends on cAMP‐response element binding protein/Brain‐derived neurotrophic facto by mediating synaptic transmission

Several studies reported the relative antidepressant effects of Fructus Aurantii (FRA) with repeated treatment, the rapid antidepressant effects of FRA and the underlying mechanisms remained unclear. We, therefore, examined the rapid antidepressant actions of FRA in behavioral tests in mice and tested the underlying molecular mechanisms. We found FRA, like ketamine, reversed the behavioral deficits both in lipopolysaccharide(LPS)‐induced and learned helplessness (LH) models at 1 day after a single administration. FRA was also capable of increasing the expressions of protein kinase A/cAMP‐response element‐binding protein/brain‐derived neurotrophic factor (PKA/CREB/BDNF) signaling in hippocampus. Consistent with ketamine, FRA up‐regulated the expressions of GABAergic receptor (GAD67) and glutamatergic receptor 1 (GluR1) in mouse hippocampus both exposed to LPS and LH. Moreover, synaptic proteins such as postsynaptic density‐95 (PSD95) and synapsin1 were also up‐regulated by a single dose of FRA both in LH and LPS models, like ketamine. Finally, metadoxine (an antagonist of CREB) inhibited the antidepressant effects of FRA in tail suspension test (TST) and forced swimming test (FST) in LPS‐induced mice, which also blocked the phosphorylation of CREB and the expressions of neurotransmitters and synaptic molecules. Therefore, FRA had rapid antidepressant effects, which depended on PKA/CREB/BDNF pathway, subsequently regulated the downstream synaptic transmission.     

Antidepressant-like effects of Xiaochaihutang in a rat model of chronic unpredictable mild stress

Ethnopharmacological relevance

Xiaochaihutang (XCHT) has been used in China for thousands of years to treat “Shaoyang syndrome”, which involves depressive-like symptoms. However, few studies have investigated its antidepressant effects and pharmacological mechanism of action. The present study was designed to confirm the antidepressant effect of XCHT using a chronic unpredictable mild stress (CUMS) model and explore its potential mechanism of action by investigating the monoamine neurotransmitters (dopamine and 5-hydroxytryptamine) and neurotrophins (BDNF and NGF).

Materials and methods

The CUMS model was established in rats, and the antidepressant effect of XCHT (0.6, 1.7 and 5 mg/kg/day, given by gastric gavage for 4 weeks) was investigated using the open field test (OFT), food consumption test and sucrose preference test. The concentrations of 5-HT and DA in the hippocampus were measured by high performance liquid chromatography with electrochemical detection (HPLC-ECD). The expressions of brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), and their receptors tyrosine receptor kinase B (TrkB) and tyrosine receptor kinase A (TrkA) in the hippocampus were measured by immunohistochemical staining analysis.

Results

CUMS caused a significant decrease in OFT, food consumption and sucrose preference in rats, and these depression-like behaviors were significantly improved by XCHT (1.7 and 5 g/kg/day). Moreover, XCHT significantly increased the concentrations of 5-HT (0.6 and 5 g/kg/day) and DA (5 g/kg/day), and improved the BDNF, NGF, TrkB and TrkA expressions in the hippocampus (1.7 and 5 g/kg/day), which was reduced in CUMS rats.

Conclusion

The results obtained suggested that XCHT may have therapeutic actions on depression-like behavior induced by CUMS in rats possibly mediated by increasing the monoamine neurotransmitter concentration and neurotrophin expression in the hippocampus.     

逍遥散对抑郁大鼠海马CA1区PI3K/AKT信号通路的调节作用研究

目的:本研究旨在探讨逍遥散通过调节PI3K/Akt信号通路进而改善由谷氨酸引起的兴奋性损伤的机制。方法:100只雄性SD大鼠随机分为正常组、模型组、逍遥散组和氟西汀组,利用CUMS方法造模成为抑郁模型大鼠,上述组别分别予以双蒸水、双蒸水、逍遥散药液、氟西汀溶液连续灌胃3周,后进行行为学观察及相关指标检测。采用旷场试验(OFT)和蔗糖偏好试验(SPT)评价逍遥散的抗抑郁作用;ELISA法测定海马组织中5-HT、NE水平;比色法检测各组大鼠海马CA1区谷氨酸水平;RT-qPCR检测海马CA1区NR2B、PI3K的mRNA水平;western blot检测海马CA1区NR2B、PI3K、P-AKT、Akt的蛋白表达。结果:逍遥散的体内干预可显著提高抑郁模型大鼠海马组织中的5-HT、NE水平、降低海马CA1区谷氨酸水平、增加了海马CA1区NR2B、PI3K及P-AKT/Akt比值,显著改善了大鼠的抑郁症状。结论:逍遥散可显著改善经慢性应激刺激后大鼠的抑郁样行为,其机制可能与降低谷氨酸兴奋性毒性,从而提高PI3K/Akt信号通路活性有关。     

中药抗肿瘤血管生成的信号通路研究

血管生成是肿瘤发生和转移的基本条件。调控肿瘤血管生成相关的信号通路包括PI3K/Akt/mTOR、Ras/Raf/MEK/ERK、Notch转导通路等。中药抗肿瘤血管生成的信号通路研究越来越受关注。调控PI3K/Akt/mTOR通路的中药多集中于抑制Akt的磷酸化,且清热药居多。调控Ras/Raf/MEK/ERK通路的中药多集中于抑制ERK的磷酸化,且活血化瘀药居多。调控Notch转导通路的中药多集中于抑制Notch1的表达,对配体的表达不一。对中药抗肿瘤血管生成的信号通路进行综述,旨在寻求新的血管生成抑制剂,阐明作用靶点,为肿瘤研究提供方向。     

对药酸枣仁-合欢花对抑郁模型大鼠行为学及皮质ERK-CREB细胞信号转导通路的影响

目的探讨对药酸枣仁-合欢花对抑郁模型大鼠行为学及皮质细胞外信号调节蛋白激酶(ERK)-环磷腺苷反应元件结合蛋白(CREB)细胞信号传导通路的影响。方法将雄性2月龄SD大鼠75只,按随机数字表法分为正常组、模型组、中药组、西药组、PD184161组,每组15只。采用孤养加慢性不可预知性温和应激(CUMS)复制大鼠抑郁模型,于实验前1d及实验第1、2、3周末用旷场实验、糖水消耗实验观察各组大鼠的行为学改变。采用实时荧光定量聚合酶链式反应(Real-Time PCR)法对皮质CREB、BDNF mRNA行定量分析。蛋白质免疫印迹(Western Blot)法测皮质ERK1/2、p-ERK1/2、p-RSK及p-CREB蛋白表达水平。结果与正常组比较,模型组大鼠旷场实验得分、糖水消耗度下降,从第2周末开始有统计学意义(P<0.05,P<0.01)、皮质CREB、BDNF mRNA水平下降(P<0.05,P<0.01)、ERK1/2、p-ERK1/2、p-RSK、p-CREB蛋白表达降低(P<0.05,P<0.01);与模型组比较,中药组、西药组、PD184161组大鼠旷场实验得分、糖水消耗度提高,从第2周末开始有统计学意义(P<0.05,P<0.01),皮质CREB、BDNF mRNA水平上调(P<0.05),ERK、p-ERK、p-RSK、p-CREB蛋白表达增强(P<0.05,P<0.01);与中药组比较,PD184161组大鼠旷场实验得分、糖水消耗度下降,第3周末有统计学意义(P<0.05),皮质CREB、BDNF mRNA水平下降(P<0.05),ERK、p-ERK、p-RSK、p-CREB蛋白表达降低(P<0.05)。结论对药酸枣仁-合欢花能够改善抑郁模型大鼠的抑郁症状,具有抗抑郁功效,其作用机制可能与激活ERK-CREB信号传导通路,增强通路中关键因子的表达有关。     

Brassinin Induces Apoptosis in PC‐3 Human Prostate Cancer Cells through the Suppression of PI3K/Akt/mTOR/S6K1 Signaling Cascades

The oncogenic PI3K/Akt/mammalian target of rapamycin (mTOR) signaling axis and its downstream effector, the ribosomal protein S6 kinase 1 (S6K1) play a key role in mediating cell survival in various tumor cells. Here, we investigated the effects of brassinin (BSN), a phytoalexin first identified as a constituent of cabbage, on the PI3K/Akt/mTOR/S6K1 activation, cellular proliferation, and apoptosis in PC‐3 human prostate cancer. BSN exerted a significant dose‐dependent cytotoxicity and reduced constitutive phosphorylation of Akt against androgen‐independent PC‐3 cells as compared to androgen‐dependent LNCaP cells. Moreover, knockdown of androgen receptor (AR) by small interfering RNA enhanced the potential effect of BSN on induction of apoptosis in LNCaP cells. BSN clearly suppressed the constitutive activation of PI3K/Akt/mTOR/S6K1 signaling cascade, which correlated with the induction of apoptosis as characterized by accumulation of cells in subG1 phase, positive Annexin V binding, TUNEL staining, loss of mitochondrial membrane potential, down‐regulation of antiapoptotic and proliferative proteins, activation of caspase‐3, and cleavage of PARP. Additionally, BSN could block broad‐spectrum inhibition of PI3K/Akt/mTOR/S6K1 axes, and aberrant Akt activation by pcDNA3‐myr‐HA‐Akt1 plasmid could not prevent the observed suppressive effect of BSN on constitutive mTOR activation. Finally, overexpression of Bcl‐2 also attenuated BSN‐mediated apoptosis in PC‐3 cells. Taken together, our findings suggest that BSN can interfere with multiple signaling cascades involved in tumorigenesis and might be provided as a potential therapeutic candidate for both the prevention and treatment of prostate cancer. Copyright © 2013 John Wiley & Sons, Ltd.     

六味地黄汤干预抑郁大鼠学习记忆的作用机制

目的:探讨六味地黄汤对慢性抑郁大鼠记忆障碍的改善作用,并探讨其可能的作用机制。方法:Wistar雌性大鼠随机分为正常组(生理盐水)、慢性不可预见性温和应激(CUMS)模型组(生理盐水)、六味地黄汤低、中、高剂量组(2. 60,7. 81,23. 50 g·kg~(-1)·d~(-1))。除正常组外,其余各组造成CUMS模型。每周称体质量,观察其行为学指标变化;实时荧光定量聚合酶链式反应(Real-time PCR)检测其海马G蛋白偶联雌激素受体(GPR30),胞内磷脂酰肌醇激酶(PI3K),环磷酸腺苷反应元件结合蛋白(CREB),脑源性神经营养因子(BDNF) mRNA的表达;酶联免疫吸附测定(ELISA)检测血清中雌激素含量。结果:与正常组比较,模型组体质量、活动能力、兴趣等明显降低(P 0. 05,P 0. 01);与模型组比较,六味地黄汤2. 60,7. 81,23. 50 g·kg~(-1)可明显提高CUMS大鼠糖水偏好度(P 0. 01)和旷场实验的站立次数(P 0. 01);7. 81,23. 50 g·kg~(-1)明显提高旷场实验的总距离(P 0. 05,P 0. 01);2. 60,7. 81 g·kg~(-1)可缩短水迷宫实验寻台潜伏期(P 0. 01);7. 81 g·kg~(-1)可增加血清中雌激素含量(P 0. 05);CUMS模型组大鼠海马组织内的GPR30,PI3K,CREB,BDNF mRNA表达明显下降(P 0. 05,P 0. 01),六味地黄汤2. 60 g·kg~(-1)显著增加海马组织内的GPR30,CREB mRNA表达(P 0. 05,P 0. 01),7. 81 g·kg~(-1)明显增加海马组织内的GPR30,PI3K,CREB,BDNF mRNA表达量(P 0. 05,P 0. 01)。结论:六味地黄汤具有抗抑郁作用,逆转CUMS大鼠抑郁样行为及学习记忆障碍,其中中剂量组药效最显著。其作用机制可能与增加血清中雌激素和提高大鼠海马GPR30,PI3K,CREB,BDNF mRNA表达有关。