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排序方式: 共有2258条查询结果,搜索用时 15 毫秒
1.
目的 探究补肾活血方对血管性痴呆(Vascular Dementia, VD)大鼠模型自噬的影响。方法 52周龄SD雄性大鼠50只,随机分为假手术组(Sham组)、模型组(VD组)、模型+补肾活血方组(BSHX组)、模型+雷帕霉素组(Rap组)和模型+3-甲基腺嘌呤组(3-MA组),每组10只大鼠。除Sham组外其余各组采用两血管阻断法(2-VO)建立VD模型。BSHX组中药灌胃治疗28天;自噬干预组于造模前30 min侧脑室给药。运用Morris水迷宫测试各组大鼠的学习记忆能力;通过尼氏染色和透射电子显微镜(Transmission electron microscope,TEM)观察大鼠海马区病理形态及自噬变化;采用蛋白免疫印迹(Western blot)法和反转录实时荧光定量PCR(RT-qPCR)检测大鼠海马Beclin-1、P62以及微管相关蛋白1轻链3(LC3)蛋白及mRNA表达情况。结果 与VD组比较,BSHX组大鼠学习记忆能力显著提升(P<0.05),镜下观察BSHX组和3-MA组的细胞形态及数量均有改善,自噬小体鲜见,Beclin-1以及LC3蛋白和mRNA表达水平显著降低(P<0.05),P62蛋白和mRNA表达水平明显升高(P<0.05)结论 补肾活血方可以降低VD大鼠海马区Beclin-1和LC3蛋白及mRNA的表达,提高P62的表达,通过抑制自噬的发生,减轻对神经细胞的损伤,改善学习记忆能力。  相似文献   
2.
The present study aims to shed new light on anti-aging effect of DL-β-hydroxybutyrate (βOHB) against hepatic cellular senescence induced by d-galactose or γ-irradiation. The rats divided into 6 groups. Group 1, control, group 2, exposed to γ-ray (5 GY), group 3, injected by d-galactose (150 mg/kg) daily for consecutive 6 weeks, which regarded to induce the aging, group 4, injected intraperitoneal by β-hydroxybutyrate (βOHB) (72.8 mg/kg) daily for consecutive 14 days, group 5, exposed to γ-ray then treated with βOHB daily for consecutive 14 days, group 6, injected daily with d-galactose for consecutive 6 weeks, then treated with βOHB daily at the last two weeks of d-galactose. Aspartate amino transferase (AST), alanine amino transferase (ALT), Insulin, interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were estimated in serum. Moreover, protein expression of Microtubule-associated proteins 1A/1B light chain 3B (LC3-II/LC3-I) ratio, mechanistic target of rapamycin (mTOR), pAMPK, mRNA gene expression of 5′ AMP-activated protein kinase (AMPK), Nucleoporin p62 (p62), cyclin-dependent kinase inhibitor 1(P21CIP1), cyclin-dependent kinase inhibitor 2A (p16INK4a) and DNA fragmentation percentage were measured in liver tissue as a biomarker of cellular senescence. The results confirmed that βOHB modulated serum level of AST, ALT, insulin, IL-6 and TNF-α, protein expression of mTOR and LC3-II/LC3-I ratio, pAMPK and p62 in liver aging model induced by d-galactose or γ-irradiation. Histopathological examination results of liver tissue indicated coincidence with those recorded by molecular biochemical inspection. Taken together, these findings suggest that βOHB may be useful in combating hepatic cellular senescence induced by d-galactose or γ-irradiation via autophagy dependent mechanisms.  相似文献   
3.
Estradiol, either from peripheral or central origin, activates multiple molecular neuroprotective and neuroreparative responses that, being mediated by estrogen receptors or by estrogen receptor independent mechanisms, are initiated at the membrane, the cytoplasm or the cell nucleus of neural cells. Estrogen-dependent signaling regulates a variety of cellular events, such as intracellular Ca2+ levels, mitochondrial respiratory capacity, ATP production, mitochondrial membrane potential, autophagy and apoptosis. In turn, these molecular and cellular actions of estradiol are integrated by neurons and non-neuronal cells to generate different tissue protective responses, decreasing blood-brain barrier permeability, oxidative stress, neuroinflammation and excitotoxicity and promoting synaptic plasticity, axonal growth, neurogenesis, remyelination and neuroregeneration. Recent findings indicate that the neuroprotective and neuroreparative actions of estradiol are different in males and females and further research is necessary to fully elucidate the causes for this sex difference.  相似文献   
4.
Diabetes mellitus is a chronic metabolic disorder that has a complex molecular and cellular pathophysiology, resulting in its dynamic progression and that may show differing responses to therapy. The incidence of diabetes mellitus increases with age and requires additive therapeutic agents for its management. SGLT2i and DPP-4 inhibitors and GLP-1 receptor agonists (GLP-1RA) are newly introduced antidiabetic drugs that work through differing mechanisms; DPP-4 inhibitors maintain the endogenous level of GLP1; GLP-1RA result in pharmacological levels of GLP1, whilst SGLT2i act on the proximal tubules of the kidney. They have shown efficacy in the management of diabetes and in contrast to other antidiabetic drugs, do not inherently cause hypoglycemia in therapeutic doses. Autophagy as a highly conserved mechanism to maintain cell survival and homeostasis by degradation of damaged or aged organelles and components, and recognised to be increasingly important in diabetes. In the present review, we discuss the modulatory effects of these newly introduced antidiabetic drugs on the autophagy process.  相似文献   
5.
目的探讨狼疮肾炎(lupus nephritis,LN)患者自噬水平及其对足细胞相关蛋白表达水平的影响。方法选择2017年5月至2019年5月于榆林市第一医院收治的69例LN患者为LN组,50例系统性红斑狼疮(systemic lupus erythematosus,SLE)患者为SLE组,50例肾切除手术患者为对照组,观察3组肾脏足细胞内自噬体数量,比较3组肾脏组织中自噬相关蛋白、微管相关蛋白轻链3(LC3)、B淋巴细胞瘤蛋白质-2-相互作用蛋白(Beclin1)的表达,以及足细胞相关蛋白,肾病蛋白(Nephrin)、足突蛋白(Podocin)的表达。分离狼疮肾炎患者肾脏足细胞,将足细胞分为自噬抑制组和自噬诱导组,自噬抑制组加入100 nmol/L 3-甲基腺嘌呤(3-MA),自噬诱导组加入100 nmol/L雷帕霉素(RAPA),比较3组足细胞内自噬体数量及LC3、Beclin-1、Podocin、Nephrin等蛋白的表达。结果LN组、SLE组肾脏足细胞内自噬体数量及LC3、Beclin-1、Podocin、Nephrin蛋白表达量显著高于对照组(P<0.05);SLE组肾脏足细胞内自噬体数量及LC3、Beclin-1、Podocin、Nephrin蛋白表达量显著高于LN组(P<0.05);自噬诱导组足细胞内自噬体数量及LC3、Beclin-1、Podocin、Nephrin蛋白表达量显著高于正常对照组、自噬抑制组(P<0.05);正常对照组足细胞内自噬体数量及LC3、Beclin-1、Podocin、Nephrin蛋白表达量显著高于自噬抑制组(P<0.05)。结论LN患者自噬水平呈升高状态,自噬水平升高可能通过上调足细胞相关蛋白Podocin、Nephrin水平而减轻足细胞损伤,抑制LN病情进展。  相似文献   
6.
7.
A combination of various therapeutic approaches has emerged as a promising strategy for cancer treatment. A safe and competent nano-delivery system is thus in urgent demand to facilitate the simultaneous transport of various therapeutic agents to cancer cells and a tumor region to achieve synergistic effect. Gold nanoparticles (GNPs) and mesoporous silica nanoparticle (MSNs) were fabricated herein as potential candidates for drug delivery. Serving as gatekeepers, GNPs (5 nm in diameter) were attached onto the amino-functionalized MSNs (denoted as NMSNs) via a relatively weak gold–nitrogen bonding. The resulting nanohybrids (denoted as GCMSNs) were uptaken by cells, and the detachment of GNPs and subsequent intracellular drug release from NMSNs were achieved by competitive binding of intracellular glutathione to GNPs. In addition to the function of gatekeeping, GNPs also play another role as the oxidative stress elicitor. Our in vitro studies revealed that GCMSNs induced higher oxidative stress in lung cancer cells (A549) than in normal cells (3T3-L1). This growth inhibitory effect found in the cancer cells was likely induced by mitochondria dysfunction originated from the GCMSN-induced, oxidative stress-triggered mitochondria-mediated autophagy. The redox-responsive nanohybrids were further loaded with camptothecin and the intensified synergistic therapeutic effects were observed associated with combined chemotherapy and oxidative stress strategy. The results clearly demonstrate that such unique nanohybrids hold great promise for selective and effective cancer treatments.  相似文献   
8.
Malignant glioma is the most common intracranial tumor with a dismal prognosis. The radiosensitizing effect of silver nanoparticles (AgNPs) on glioma both in vitro and in vivo had been demonstrated in the previous studies of our group. However, the underlying mechanism is still unclear. Consistent with previous studies, a size and dose dependent antitumor effect and significant radiosensitivity enhancing effect of AgNPs were observed in our experiment system. We also found that cell protective autophagy could be induced by AgNPs and/or radiation, which was verified by the use of 3-MA. The mechanism through which had autophagy and the enhancement of radiosensitivity taken place was further investigated with inhibitors of ERK and JNK pathways. We demonstrated that ERK and JNK played pivotal roles in the radiosensitivity enhancement. Inhibiting ERK and JNK with U0126 and SP600125 respectively, we found that the autophagy level of the cells treated with AgNPs and radiation were attenuated. Moreover, SP600125 down-regulated the apoptosis rate of the co-treated cells significantly. Taken together, the present study would have important impact on biomedical applications of AgNPs and clinical treatment for glioma.  相似文献   
9.
目的 通过网络药理分析及相关的动物实验探讨黄芪减少糖尿病肾病蛋白尿(Diabetic nephropathy proteinuria,DNP)的作用机制。方法 利用TCMSP数据平台筛选出黄芪中的有效成分和相关靶标,使用GeneCards、OMIM网站数据库在线搜索出DNP的疾病相关靶标,取疾病和药物相同靶标交集,再利用Cytoscape 3.8.2构建药物-效应成分-疾病-靶标相互作用网络,进行拓扑学分析;从Uniprot数据库中获取靶点蛋白的基因名称,利用STRING在线数据库进行靶点蛋白与蛋白互作(Protein-protein interaction,PPI)网络分析;再进行GO功能分析和KEGG通路功能富集分析,推断黄芪减少DNP的机制是否和Akt1/mTOR自噬通路相关,再利用黄芪干预糖尿病肾病动物模型探讨其作用机制是否和预测的一致。结果 黄芪中20种核心化合物有作用靶点174个,DNP相关靶标有1862个,交集靶标有98个,关键效应分子有10个。PPI图显示黄芪发挥效应的目标蛋白主要是AKT1、VEGFA、IL6、CASP3、MAPK1、JUN等。GO分析黄芪药效主要与细胞因子受体结合及其活性、核受体活性、转录因子活性等有关,KEGG分析表明黄芪药效基础主要作用与糖尿病并发症中AGE-RAGE、MAPK、PI3K-Akt等信号通路有关。动物实验显示黄芪能明显改善糖尿病肾病的大鼠的肾功能,尤其改善蛋白尿指标,通过上调足细胞Nephrin蛋白保护了肾小球滤过屏障,减少了蛋白尿的产生(P < 0.05),同时下调了Akt1、总mTOR及其mRNA表达(P < 0.05),从而增强了肾足细胞的自噬活性,也起到减少DNP的作用。结论 网络药理分析显示黄芪可能通过多靶点效应发挥减少DNP作用,潜在的分子机制和Akt1/mTOR自噬通路有关,再经过实验研究说明Akt1/mTOR自噬通路是黄芪减少糖尿病肾病蛋白尿作用机制之一。  相似文献   
10.
目的探讨早期宫颈癌组织中自噬相关蛋白-12(ATG-12)与人乳头瘤病毒(HPV)16-E6/E7-DNA病毒载量及预后的关系。方法选取2015年1月至2017年12月期间在安徽皖北煤电集团总医院保存的宫颈活检或手术切除宫颈组织203例,包括30例慢性宫颈炎、18例宫颈上皮内瘤变(CIN)Ⅰ、23例CINⅡ、26例CINⅢ和106例早期(ⅠA2~ⅡB期)宫颈鳞状上皮癌(CSCC)。采用巢式多重聚合酶链式反应(NM-PCR)和免疫组化染色SP法检测组织中HPV 16-E6/E7-DNA病毒载量和ATG-12蛋白表达。分析ATG-12蛋白表达与早期CSCC临床病理特征的关系。随访CSCC患者无瘤生存时间(DFS)。采用Cox风险比例回归模型分析影响CSCC预后的因素。结果CSCC组织ATG-12蛋白阳性表达率为26.42%(28/106),低于慢性宫颈炎和CIN组织(P<0.05)。ATG-12蛋白表达与HPV16-E6/E7-DNA病毒载量呈负相关(r=-0.306,P=0.001;r=-0.436,P=0.001)。ATG-12蛋白表达与FIGO分期、间质浸润、淋巴脉管间隙浸润、淋巴结转移有关(P<0.05)。随访11~64个月,ATG-12蛋白阳性表达患者5年无瘤生存率为78.57%(22/28),ATG-12蛋白表达阴性患者5年无瘤生存率为60.26%(47/78)。多因素Cox风险回归模型结果显示,HPV16-E6/E7-DNA病毒载量和ATG-12蛋白表达是影响患者DFS的独立预后因素(P<0.05)。结论早期宫颈鳞状上皮癌组织中ATG-12阳性表达率低,与HPV16-E6/E7-DNA病毒载量呈负相关,有望成为评估HPV阳性早期宫颈癌患者预后的重要指标。  相似文献   
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