Inhibitor of fatty acid synthase induced apoptosis in human colonic cancer cells

INTRODUCTIONThe treatment of human epithelial malignancies islimited by drug resistance and toxic and side effects,which results in the failure in the treatment ofmajority of advanced cancer victims.To seek for anew,and specific antineoplastic therapy willprovide hope for tumor treatment.Althoughdisordered intermediary metabolism in cancer cellshas been known for many years,much of the

Targeting fatty acid synthase sensitizes human nasopharyngeal carcinoma cells to radiationvia downregulating frizzled class receptor 10

Objective:Our aim was to test the hypothesis that fatty acid synthase(FASN)expression contributes to radioresistance of nasopharyngeal carcinoma(NPC)cells and that inhibiting FASN enhances radiosensitivity.Methods:Targeting FASN using epigallocatechin gallate(EGCG)or RNA interference in NPC cell lines that overexpress endogenous FASN was performed to determine their effects on cellular response to radiationin vitro using MTT and colony formation assays,andin vivo using xenograft animal models.Western blot,immunohistochemistry,real-time PCR arrays,and real-time RT-PCR were used to determine the relationship between FASN and frizzled class receptor 10(FZD10)expression.FZD10 knockdown and overexpression were used to determine its role in mediating FASN function in cellular response to radiation.Immunohistochemical staining was used to determine FASN and FZD10 expressions in human NPC tissues,followed by analysis of their association with the overall survival of patients.Results:FASN knockdown or inhibition significantly enhanced radiosensitivity of NPC cells,bothin vitro andin vivo.There was a positive association between FASN and FZD10 expression in NPC cell lines grown as monolayers or xenografts,as well as human tissues.FASN knockdown reduced FZD10 expression,and rescue of FZD10 expression abolished FASN knockdown-induced enhancement of radiosensitivity.FASN and FZD10 were both negatively associated with overall survival of NPC patients.Conclusions:FASN contributes to radioresistance,possiblyvia FZD10 in NPC cells.Both FZD10 and FASN expressions were associated with poor outcomes of NPC patients.EGCG may sensitize radioresistance by inhibiting FASN and may possibly be developed as a radiosensitizer for better treatment of NPCs.

Herbicide-Resistant Mutations in Acetolactate Synthase Can Reduce Feedback Inhibition and Lead to Accumulation of Branched-Chain Amino Acids

The branched-chain amino acids (BCAAs) valine, leucine and isoleucine are essential amino acids that are critical for animal growth and development. Animals need to obtain BCAAs from their diet because they cannot synthesize them. Plants are the ultimate source of these amino acids. Acetolactate synthase (ALS) is the first common enzyme in the biosynthesis of BCAAs. The metabolic control of BCAA biosynthesis involves allosteric regulation of ALS by the end-products of the pathway, i.e., valine, leucine and isoleucine. ALS holoenzyme seems to consist of two large catalytic subunits and two small regulatory subunits. In a previous study, using homologous recombination dependent gene targeting we created rice plants in which W548Land S627I mutations were induced into the endogenous gene encoding the ALS catalytic subunit. These two amino acid substitutions conferred hypertolerance to the ALS-inhibiting herbicide bispyripac-sodium. In this study, we revealed that feedback regulation by valine and leucine was reduced by these two amino acid substitutions. Furthermore, in leaves and seeds of ALS mutants with W548Land/or S627I substitution, a 2- to 3-fold increase in BCAAs was detected. Our results suggest that the ALS catalytic subunit is also involved in feedback regulation of ALS, and that judicious modification of the regulatory and catalytic subunits of ALS-coding genes by gene targeting can lead to the efficient accumulation of BCAA in plants.

Fatty Acid Synthase and Hormone-sensitive Lipase Expression in Liver Are Involved in Zinc-α2-glycoprotein-induced Body Fat Loss in Obese Mice

Objective To explore the effects of zinc-α2-glycoprotein(ZAG) on body weight and body fat in high-fat-diet(HFD)-induced obesity in mice and the possible mechanism.Methods Thirty-six male mice were fed with standard food(SF)(n=9) and HFD(n=27),respectively.Five weeks later,9 mice fed with HFD were subjected to ZAG expression plasmid DNA transfection by liposome transfection method,and another 9 mice to negative control plasmid transfection.Two weeks later,serum ZAG level in the mice was assayed by Western blot,and the effects of ZAG over-expression on body weight,body fat,serum biochemical indexes,and adipose tissue of obese mice were evaluated.The mRNA expressions of fatty acid synthase(FAS) and hormone-sensitive lipase(HSL) in liver tissue were determined by reverse transcription-polymerase chain reaction.Results Serum ZAG level significantly lowered in simple HFD-fed mice in comparison to SF-fed mice(0.51±0.10 AU vs.0.75±0.07 AU,P<0.01).Further statistical analysis demonstrated that ZAG level was negatively correlated with body weight(r =-0.56,P<0.001),epididymal fat mass(r=-0.67,P<0.001),percentage of epididymal fat(r=-0.65,P<0.001),and increased weight(r=-0.57,P<0.001) in simple SF-and HFD-fed mice.ZAG over-expression in obese mice reduced body weight and the percentage of epididymal fat.Furthermore,FAS mRNA expression decreased(P<0.01) and HSL mRNA expression increased(P<0.001) in the liver in ZAG over-expressing mice.Conclusions ZAG is closely related to obesity.Serum ZAG level is inversely correlated with body weight and percentage of body fat.The action of ZAG is associated with reduced FAS expression and increased HSL expression in the liver of obese mice.

Increased fatty acid synthase as a potential therapeutic target in multiple myeloma

Objective:To determine fatty acid synthase(FAS)expression in human multiple myeloma and verify its potential as a therapeutic target in multiple myeloma.Methods:FAS expression was determined by immunohistochemistry,re- verse-transcription polymerase chain reaction(RT-PCR)and immunoblot analysis in bone marrow samples obtained from 27 patients with multiple myeloma(MM patients)and peripheral blood mononuclear cells(PBMCs)obtained from 12 healthy donors. In parallel,additional analyses were performed on 2 human multiple myeloma cell lines,U266 and RPMI8226.U266 cells were treated with cerulenin at various concentrations(5 to 320μg/ml)for 24 h,and metabolic activity was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)assays.Apoptosis was evaluated by dual Annexin V/PI (propidium iodide)labeling and flow cytometry(FCM)in U266 cells treated with 20μg/ml cerulenin for 12 h or 24 h.Results:By immunohistochemistry,we found that 19 of 27 bone marrow samples obtained from MM patients expressed significantly high levels of FAS.Similarly,by RT-PCR,22 of 27 bone marrow samples obtained from MM patients,U266 and RPMI8226 showed FAS expression,whereas PBMC samples from 12 healthy donors did not express detectable level of FAS.FAS protein expression was confirmed by immunoblot analysis in 16 of 27 bone marrow samples obtained from MM patients,U266 and RPMI8226 cell lines,and no FAS protein expression was detected in PBMC samples from 12 healthy donors.U266 cells were highly sensitive to cerulenin treatment,with a dosage-related effect on metabolic activity,as a measure for cell proliferation.U266 cells treated with 20μg/ml cerulenin for 12 and 24 h also showed early sign of apoptosis with 56.9%and 69.3%Annexin V+/PI ?cells,and late apoptotic and necrotic cells with 3.2%and 17.6%Annexin V+/PI +cells.Conclusion:Increased FAS expression existed in multiple myeloma samples and human myeloma cell lines.Cerulenin greatly inhibited metabolic activity/cell proliferation of U266 cells and induced apoptosis,suggesting that FAS is an effective target for pharmacological therapy in human multiple myeloma.

Correlation Between Hyaluronic Acid,Hyaluronic Acid Synthase And Human Renal Clear Cell Carcinoma

学习在玻尿的酸之间的关联的目的(哈) ，玻尿的酸 synthase () 并且人的肾的清楚的房间癌(RCCC ) 。三的表示有 isoforms 基因的方法并且哈在 93 RCCC 纸巾，在来自二所医院的 RCCC 边上的 27 肾的纸巾与实时 RT-PCR 西方的污点和 immunohistochemical 方法被测量并且分析。结果所有 RCCC 和邻近的正常纸巾表示了三 HASs mRNA 与蛋白质；在 mRNA 水平， RCCC 和邻近的正常纸巾，比 HAS1 或 HAS2 表示了更多的 HAS3，他们的差别是统计上重要的(所有 P 价值 < 0.05 ) ；但是在蛋白质水平，都， isoforms 介绍了相等的表示。与邻近的非肿瘤的肾纸巾相比，所有的表示在 RCCC 纸巾有 isoforms mRNA 显然被增加，他们的差别是重要的(所有 P 价值 < 0.0001 ) ；但是在蛋白质铺平，仅仅 HAS3 的表示显然增加了(P=0.022 ) 。在所有邻近的正常纸巾，超过 80% 肾的管状的房间强烈表示了哈然而，仅仅少数 RCCC 盒子(16/93 ) 介绍了弱积极哈在很少癌症巢(5%30%) 里染色，差别是重要的(P < 0.0001 ) 。在 RCCC 纸巾 subgrouped 根据临床的舞台，病理学的等级，淋巴的转移并且远转移， HASs mRNA 与蛋白质微分表示都没有统计意义(所有 P 价值 > 0.05 ) 。与另外的恶意不同的结论，哈并且 HASs (除了 HAS3 ) 不能在人的 RCCC 的生物进步起重要作用。

Effect of nitric oxide synthase inhibitor N^G-nitro-L-arginine on the content of amino acid in ischemic brain tissues of rats

BACKGROUND: Nitric oxide synthase (NOS) inhibrtors have been widely used to investigate the role of NO on cerebral ischemic injury, but the results are controversial. Moreover, it has been considered to aggravate the ischemic neuronal damage with the release of excessively excitatory amino acids (EAA) during cerebral ischemia. On the other hand, some inhibitory amino acid is suggested to be important for the neuronal protection against ischemic brain damage. Our study has recently showed that treatment with the NOS inhibitor NG-nitro-L-arginine (L-NA) reduced focal cerebral ischemic damage. The effect of L-NA on the contents of excitatory and inhibitory amino acid in the rat brain following cerebral ischemia is still unclear.OBJECTIVE: By evaluating the effect of NOS inhibitor, L-NA on the contents of aspartate, glutamate, glycine and γ-aminobutyric acid (GABA) in striatum, hippocampus and cortex in the rat brain following cerebral ischemia respectively, to investigate the beneficial effect of L-NA on cerebral ischemic injury and the possible mechanism. DESIGN: A randomized and controlled experiment.SETTING: Department of Pharmacology, Hebei Academy of Medical Sciences.MATERIALS: A total of 42 male healthy SD rats (grade Ⅱ, weighting 250-300 g) were provided by the Experimental Animal Center of Hebei Province (Certification: 04036). Aspartate, glutamate, glycine, GABA, L-NA and 2,3,5-triphenyltetrazolium chloride (TTC) were obtained from Sigma Chemicals Co, St Louis, MO, USA. HPLC-ultraviolet detector system consisted of Agilent 1100 HPLC.METHODS: The experiment was carried out in Department of Pharmrcology, Hebei Academy of Medical Sciences from June 2005 to June 2006. Rats were randomly divided into three groups: sham-operated group (n = 6), ischemic group (n = 18), L-NA group (n = 18). The model of focal cerebral ischemia in rat was prepared with intraluminal line occlusion methods. In sham-operated rats, the external carotid artery was surgically prepared, but the filament was not inserted. Each group was further divided into 3 subgroups (n = 6 for each): drugs were administrated at 2, 6 and 12 hours after the middle cerebral artery occlusion (MCAO) respectively. L-NA (20 mg/kg, ip) was administrated, twice a day, for 3 consecutive days. Same volume of normal saline was administrated in ischemic and sham operation groups. The changes of infarcted volume and the contents of amino acids were respectively assayed. Image analysis software was used for the measurement of the infarcted area. The results were expressed as a percentage of the infarcted volume of cerebral/volume of whole brain (IV%) in order to control for edema formation. The contents of aspartate, glutamate, glycine and GABA in striatum, hippocampus and cortex in the rat brain following cerebral ischemia were respectively measured by HPLC method. All data were analyzed with one-way ANOVA and Dunnett’s test.MAIN OUTCOME MEASURES: ① The volume of cerebral infarction; ② The contents of aspartate, glutamate, glycine and GABA in brain tissue after cerebral ischemia.RESULTS: All 42 rats were involved in the final analysis. ① Infarcted volume: Volume was 0 in sham-operated group. When L-NA was administrated at 2 and 6 hours after MCAO, the infarcted volume was (20.13±3.59)% and (23.12±5.84)% in L-NA group, which was not similar to that in ischemic group [(22.10±3.98)%, (25.38±5.37)%, P > 0.05]. However, the infarcted volume was markedly decreased compared with that of ischemic group when L-NA was administrated at 12 hours after MCAO [(26.11±3.55)% and (37.15±3.58)%, P < 0.01]. ② Changes of amino acid content: At 2 and 6 hours after ischemia, the contents of aspartate, glutamate, glycine and GABA in striatum, hippocampus and cortex in ischemic group were significantly increased compared with those in sham-operated group ( P < 0.05-0.01). However, contents in L-NA group were similar to those in ischemic group (P > 0.05). At 12 hours after ischemia, the contents of aspartate [(0.21±0.06), (0.36±0.05), (0.29±0.12) mg/g] and glutamate [(0.55±0.06), (0.78±0.10), (0.52±0.10) mg/g] in striatum, hippocampus and cortex in L-NA group were significantly decreased compared with those in ischemic group [(0.49±0.17), (0.63±0.03), (0.51±0.15) mg/g; (0.98±0.30), (1.15±0.15), (0.93±0.15) mg/g, P < 0.05-0.01]. Glycine in hippocampus was (0.40±0.07) mg/g, which was higher than that in ischemic group [(0.21±0.07) mg/g, P < 0.05]. GABA in striatum, hippocampus and cortex was (0.93±0.10), (0.62±0.12) and (0.81±0.10) mg/g, respectively, which was higher than that in ischemic group [(0.60±0.08), (0.37±0.17), (0.59±0.10) mg/g, P < 0.05-0.01]. CONCLUSION: It may be concluded that L-NA have beneficial effect on ischemic cerebral injury in ischemic later stage in rats. The possible mechanism is that L-NA can decrease the contents of aspartate and glutamate, increase the contents of glycine and GABA.

Evaluation of Circulating Fatty Acid Synthase as a Biomarker in Non-Alcoholic Fatty Liver Disease

Background: The liver is the corner stone in lipid metabolism, free fatty acid uptake, synthesizing, storing and exporting lipids;non-alcoholic fatty liver disease (NAFLD) develops if there is any interruption or derangements in lipid metabolim. Fatty acid synthase (FAS) is the major enzyme in lipogenesis, and its circulating level is a bi-omarker of metabolically demanding human diseases. Aim of the Work: To evaluate the level of circulating FAS in NAFLD patients and to correlate it to serum lipid pa-rameters. Materials and Methods: The study included forty NAFLD patients and forty age and sex-matched healthy subjects as controls. Results: FAS levels were signifi-cantly higher in NAFLD patients compared to their level in the controls (P < 0.05). Ad-ditionally, a positive correlation was found between the levels of FAS and BMI (r = 0.57), and between FAS levels and triglycerides and low density lipoprotein cholesterol levels in NAFLD patients (r = 0.79 & 0.53, respectively). Conclusion: Elevated levels of circulating FAS can be considered as a biomarker of fatty liver disease.

Protection of INS-1 Cells from Free Fatty Acid-induced Apoptosis by Inhibiting the Glycogen Synthase Kinase-3

To examine the role of glycogen synthase kinase 3(GSK-3) in the apoptosis of pancreatic β-cells to better understand the pathogenesis and to find new approach to the treatment of type 2 diabetes,apoptosis was induced by oleic acid(OA) in INS-1 cells and the activity of GSK-3 was inhibited by LiCl.The PI staining and flow cytometry were employed for the evaluation of apoptosis.The phosphorylation level of GSK-3 was detected by Western blotting.The results showed that OA at 0.4 mmol/L could cause conspicuous apoptosis of INS-1 cells and the activity of GSK-3 was significantly increased.After the treatment with 24 mmol/L of LiCl,a inhibitor of GSK-3,the OA-induced apoptosis of INS-1 cells was lessened and the phosphorylation of GSK-3 was increased remarkably.It is concluded that GSK-3 activation plays an important role in OA-induced apoptosis in pancreatic β-cells and inhibition of the GSK-3 activity can effectively protect INS-1 cells from the OA-induced apoptosis.Our study provides a new experimental basis and target for the clinical treatment of type-2 diabetes.

Chlorogenic acid protection of neuronal nitric oxide synthase-positive neurons in the hippocampus of mice with impaired learning and memory

BACKGROUND:Clinical practice and modern pharmacology have confirmed that chlorogenic acid can ameliorate learning and memory impairments. OBJECTIVE: To observe the effects of chlorogenic acid on neuronal nitric oxide synthase (nNOS)-positive neurons in the mouse hippocampus,and to investigate the mechanisms underlying the beneficial effects of chlorogenic acid on learning and memory. DESIGN,TIME AND SETTING: The present randomized,controlled,neural cell morphological observation was performed at the Institute of Neurobiology,Central South University between January and May 2005. MATERIALS: Forty-eight female,healthy,adult,Kunming mice were included in this study. Learning and memory impairment was induced with an injection of 0.5 μL kainic acid (0.4 mg/mL) into the hippocampus. METHODS: The mice were randomized into three groups (n=16): model,control,and chlorogenic acid-treated. At 2 days following learning and memory impairment induction,intragastric administration of physiological saline or chlorogenic acid was performed in the model and chlorogenic acid-treated groups,respectively. The control mice were administered 0.5 μL physiological saline into the hippocampus,and 2 days later,they received an intragastric administration of physiological saline. Each mouse received two intragastric administrations (1 mL solution once) per day,for a total of 35 days. MAIN OUTCOME MEASURES: Detection of changes in hippocampal and cerebral cortical nNOS neurons by immunohistochemistry; determination of spatial learning and memory utilizing the Y-maze device. RESULTS: At day 7 and 35 after intervention,there was no significant difference in the number of nNOS-positive neurons in the cerebral cortex between the model,chlorogenic acid,and control groups (P > 0.05). Compared with the control group,the number of nNOS-positive neurons in the hippocampal CA1-4 region was significantly less in the model group (P<0.05). However,the control group was not different from the chlorogenic acid-treated group (P > 0.05). At day 7 following intervention,the number of correct responses in the Y-maze test was greater in the chlorogenic acid-treated group than in the model group. CONCLUSION: Chlorogenic acid protects kainic acid-induced injury to nNOS-positive neurons in the hippocampal CA1-4 regions,thereby ameliorating learning and memory impairment.

Coexistence of nitric oxide synthase with γ-aminobutyric acid during seizure induced by kainic acid in SD rats

Objective: Functional significance of NO and central inhibitory neurotransmitter γ-aminobutyric(GABA) during seizures were investigated morphorlogically. Methods: A kainate-induced complex partialseizure model was used in our experiment. Twenty SD rats were randomly divided into KA 30, 60, 90, 200min and control groups. The brain sections were stained by NADPh (nicotinamide adenine dinucleotide phosphate ) diaphorase (Nd ) histochemically, and were further stained by GABA immunohistochemically.Results: Histological and immunohistochemical study revealed that in KA groups the number of Nd and GABA-positive double labelled neurons in CA3 region, CA3 region and dentate gyms was significantly reduced,compared with the control group. Conclusion: Nd coexisted with GABA in the brain. Reduction of GABA release led to relief of GABA-ergic inhibition and in the same way, reduction of NO release weakened its negative feedback modulation. Therefore neuronal synchronous paroxysmal discharges increased. GABA and NO,both having antiepileptic action, acted through different ways or different link in the same way. NO may involve in the effect of GABA-ergic neurons and play cooperative antiepileptic action with GABA.

基于Fas/FasL信号通路探索舒芬太尼对急性心肌梗死大鼠心功能和心肌细胞凋亡的影响

目的基于脂肪酸合成酶(Fas)/脂肪酸合成酶配体(FasL)信号通路探索舒芬太尼对急性心肌梗死(AMI)大鼠心功能和心肌细胞凋亡的影响。方法选择健康雄性SD大鼠108只,适应性饲养7天,随机分为对照组、模型组、舒芬太尼低剂量组、舒芬太尼高剂量组、舒芬太尼高剂量+Fas阴性对照组、舒芬太尼高剂量+Fas慢病毒组,每组18只。模型组、舒芬太尼低剂量组、舒芬太尼高剂量组、舒芬太尼高剂量+Fas阴性对照组、舒芬太尼高剂量+Fas慢病毒组通过冠状动脉左前降支结扎法制作AMI模型;对照组除不结扎冠状动脉左前降支外,其余步骤与AMI模型相同。舒芬太尼低剂量组和舒芬太尼高剂量组分别于AMI模型制作成功后腹腔注射0.1、1µg/kg舒芬太尼。舒芬太尼高剂量+Fas阴性对照组和舒芬太尼高剂量+Fas慢病毒组分别于AMI模型制作成功后腹腔注射1µg/kg舒芬太尼,尾静脉注射200 nmol/kg NC shRNA慢病毒或Fas shRNA慢病毒。对照组和模型组腹腔注射等量生理盐水。术后72 h,采集大鼠尾静脉血,采用ELISA法检测血清肌钙蛋白T;采用超声心动图检测左心室射血分数(LVEF)、左心室缩短分数(LVFS)、左心室舒张末期内径(LVEDd)和左心室收缩末期内径(LVESd)。待大鼠心功能检测完成后,腹主动脉取血,采用ELISA法检测血清TNF-α、IL-6。所有大鼠断头处死,留取心脏,随机取6只大鼠的心脏组织,TTC染色,计算心肌梗死面积;随机取6只大鼠的心脏组织,HE染色,观察心肌组织病理形态变化,采用TUNEL法检测细胞凋亡情况;取剩余6只大鼠的心脏组织,采用Western blotting法检测细胞凋亡相关蛋白Bcl-2、Bax、Caspase-3及Fas/FasL信号通路相关蛋白表达。结果与对照组比较,模型组血清肌钙蛋白T水平升高,LVEDd、LVESd升高,LVEF、LVFS降低,血清TNF-α、IL-6水平升高,心肌梗死面积增大,细胞凋亡率及Bax、Caspase-3、Fas、FasL蛋白表达升高,Bcl-2蛋白表达下降(P均<0.05);与对照组比较,模型组心肌细胞形态模糊、纹理消失、排列紊乱、心肌间小血管扩张、细胞数量减少,可见大量炎性细胞浸润。与模型组比较,舒芬太尼低剂量组和舒芬太尼高剂量组血清肌钙蛋白T水平降低,LVEDd、LVESd降低,LVEF、LVFS升高,血清TNF-α、IL-6水平降低,心肌梗死面积减小,细胞凋亡率及Bax、Caspase-3、Fas、FasL蛋白表达降低,Bcl-2蛋白表达升高(P均<0.05);与模型组比较,舒芬太尼低剂量组和舒芬太尼高剂量组心肌细胞形态、纹理、排列、血管扩张、细胞数量及炎性细胞浸润显著改善。以舒芬太尼高剂量组上述效果改善较为明显。与舒芬太尼高剂量+Fas阴性对照组比较,舒芬太尼高剂量+Fas慢病毒组血清肌钙蛋白T水平升高,LVEDd、LVESd升高,LVEF、LVFS降低,血清TNF-α、IL-6水平升高,心肌梗死面积增大,细胞凋亡率及Bax、Caspase-3、Fas、FasL蛋白表达升高,Bcl-2蛋白表达降低(P均<0.05);与舒芬太尼高剂量+Fas阴性对照组比较,舒芬太尼高剂量+Fas慢病毒组心肌细胞形态模糊、纹理消失、排列紊乱、心肌间小血管扩张、细胞数量减少,炎性细胞浸润明显。结论舒芬太尼可改善AMI大鼠心功能,抑制心肌细胞凋亡,并且1µg/kg舒芬太尼的作用效果要优于0.1µg/kg舒芬太尼;抑制Fas/FasL信号通路激活可能是舒芬太尼改善AMI大鼠心功能的作用机制之一。

基于PI3K/AKT/GSK-3β信号通路探讨EA改善APP/PS1双转基因小鼠认知功能障碍的内在机制

目的探讨鞣花酸(ellagicacid,EA)对APP/PS1双转基因小鼠认知功能的影响,并基于磷脂酰肌醇3-激酶/蛋白激酶B/糖原合成酶激酶-3(PI3K/AKT/GSK-3β)信号通路探讨鞣花酸对双转基因小鼠海马氧化应激水平的调节机制。方法将32只SPF级6月龄APP/PS1双转基因小鼠随机分为4组,即APP/PS1组、APP/PS1+EA组、APP/PS1+LY294002组、APP/PS1+EA+LY294002组,每组8只,另外选取8只SPF级C57BL/6J野生型小鼠(Wildtype)作为空白对照组,即WT组。APP/PS1+EA组给予50mg·kg^(-1)·d^(-1)灌胃EA;APP/PS1+LY294002组予以1.5mg·kg^(-1)·d^(-1)腹腔注射PI3K抑制剂LY294002;APP/PS1+EA+LY294002组予以50mg·kg^(-1)·d^(-1)灌胃EA,同时按1.5mg·kg^(-1)·d^(-1)腹腔注射LY294002;WT组和APP/PS1组于相同时间点灌胃等体积10%二甲基亚砜(DMSO)。每日给药1次,连续给药60天。Morris水迷宫检测小鼠学习和记忆能力,免疫组化、蛋白免疫印迹法检测PI3K、AKT、GSK-3β相关蛋白的表达,透射电镜观察小鼠海马组织超微结构变化。结果与WT组相比,其他四组的逃避潜伏期均增长(P<0.05),穿越平台次数明显减少(P<0.01);APP/PS1组、APP/PS1+LY294002组和APP/PS1+EA+LY294002组中的PI3K、AKT蛋白表达量显著降低(P<0.01),GSK-3β表达量显著升高(P<0.01);APP/PS1+EA组的PI3K表达量降低(P<0.05),AKT表达量显著降低(P<0.01),GSK-3β表达量升高(P<0.05);与WT组相比,APP/PS1组海马神经元细胞数目较少,线粒体结构破坏,大部分线粒体出现肿胀,线粒体的内膜和外模不完整,部分线粒体嵴消失,微管、微丝缠结,排列紊乱,而APP/PS1+EA组神经元细胞数较APP/PS1组增多,线粒体结构较清晰,可见清楚的线粒体嵴,线粒体轻度水肿。微管、微丝排列较整齐有序。结论鞣花酸改善AD模型小鼠的学习和记忆能力、减少海马神经元细胞损伤和凋亡,其作用机制可能是通过调节PI3K、AKT、GSK-3β等相关蛋白降低AD模型小鼠海马氧化应激水平。

体外催化花生四烯酸生产前列腺素F_(2α)

前列腺素F_(2α)(PGF_(2α))具有广泛的生理活性,是一种重要的脂质介质。为了实现PGF_(2α)的绿色生物合成,构建了pET30a-TbPGFS、pET30a-MmPGHS、pET30a-GvPGHS载体并在大肠杆菌BL21(DE3)中分别表达,同时对异丙基-β-D-硫代半乳糖苷(IPTG)诱导表达条件进行了优化以提高重组蛋白在大肠杆菌中的表达量。另外,以最佳诱导表达条件下得到的重组蛋白为催化剂,催化花生四烯酸合成PGF_(2α)。结果表明:MmPGHS蛋白在大肠杆菌中没有表达;GvPGHS蛋白的最佳诱导表达条件为诱导剂IPTG浓度0.2 mmol/L、诱导温度30℃、诱导时间2 h,TbPGFS蛋白的最佳诱导表达条件为诱导剂IPTG浓度0.2 mmol/L、诱导温度30℃、诱导时间6 h;在最佳诱导表达条件下,由GvPGHS和TbPGFS的粗酶液构成的双酶催化未能检测到产物PGF_(2α),而在酶偶联化学催化时,GvPGHS能将花生四烯酸转化为PGH_(2),PGH_(2)被SnCl_(2)进一步还原为PGF_(2α)。综上,通过体外酶促反应结合化学法可高效转化花生四烯酸生产PGF_(2α)。

脂肪酸合酶及其抑制剂在子宫内膜癌中的研究进展

脂肪酸合酶(fatty acid synthase,FASN)是脂肪酸合成的关键酶,可催化脂质从头合成。正常组织中的脂肪酸大多来源于食物,而在子宫内膜癌细胞中脂肪酸依赖于脂质的从头合成。既往研究表明,FASN的表达与子宫内膜癌的发生、发展及预后不良相关,FASN的过表达与丝裂原细胞外激酶(mitogen extracellular kinase,MEK)/细胞外信号调节激酶(extracellular signal-regulated kinase,ERK)/丝裂原激活的蛋白激酶(mitogen-activated protein kinase,MAPK)和磷脂酰肌醇3激酶(phosphoinositide 3-kinase,PI3K)/蛋白激酶B(protein kinase B,Akt)/哺乳动物雷帕霉素靶蛋白(mammalian target of rapamycin,mTOR)信号转导通路相关。因此,特异性阻断FASN的活性可显著抑制肿瘤细胞的生长和增殖。综述子宫内膜癌中FASN的作用机制、FASN抑制剂(如C75、C93、奥利司他等)在子宫内膜癌或其他肿瘤中的研究进展,旨在为子宫内膜肿瘤的治疗提供新思路。

文冠果种子高表达XsKCS7基因的克隆和酵母表达功能鉴定

[目的]探究调控文冠果种子神经酸合成关键基因。[方法]本研究根据参考基因组联合转录组分析文冠果3-酮酯酰-CoA合酶(3-ketoacyl-CoA synthase,KCS)基因家族在不同发育时期种子中的表达模式;通过RT-PCR扩增文冠果XsKCS7基因并进行生物信息学分析;XsKCS7基因异源转化酿酒酵母鉴定基因功能。[结果]文冠果XsKCS7基因在不同发育时期种子中的表达量远高于其他KCS基因;克隆XsKCS7基因,生物信息学分析显示,XsKCS7基因的开放阅读框为1512 bp,编码503个氨基酸,含有典型的KCS家族保守基序“GMGCSA”、“FGNTSSSS”以及“GSGFKCNSAVW”,与橡胶树KCS的亲缘性关系最近,为67.62%;XsKCS7异源转化酿酒酵母鉴定其具有调控芥酸和神经酸合成的功能。[结论]XsKCS7基因确为调控文冠果种子芥酸和神经酸合成的关键基因。

王浆酸对人结肠癌SW620细胞增殖的抑制作用及其网络药理学分析

目的:基于网络药理学探讨王浆酸(10-HDA)对人结肠癌SW620细胞增殖和迁移的影响,阐明其相关分子机制。方法:利用中药系统药理学(TMSCP)数据库和中医药综合数据库(TCMID)以关键词“蜂王浆”进行检索得到10-HDA等活性成分及对应靶点,采用Swiss Target Prediction数据库预测小分子靶点。采用Gene Cards数据库和在线人类孟德尔遗传(OMIM)数据库以关键词“Colon Cancer”获得靶点,利用String数据库和Cytoscape 3.8.0软件构建蛋白-蛋白互作(PPI)网络,筛选核心靶点;利用Metascape数据库对基因本体(GO)功能富集和京都基因与基因组百科全书(KEGG)信号通路进行富集分析,筛选特有成分10-HDA进行体外活性实验。将生长状态良好的人结肠癌SW620细胞分为对照组和不同剂量(1、5、10、15和20 mmol·L^(-1))10-HDA组,采用MTT法检测各组细胞活性并计算细胞存活率。SW620细胞分为对照组、低剂量(5 mmol·L^(-1))10-HDA组、中剂量(10mmol·L^(-1))10-HDA组和高剂量(15mmol·L^(-1))10-HDA组,Hoechst33342染色法观察各组细胞形态表现,细胞划痕实验检测各组细胞划痕愈合率,流式细胞术检测各组不同细胞周期细胞百分率,生化法检测各组细胞中总抗氧化能力(T-AOC)和超氧化物歧化酶(SOD)活性,Western blotting法检测各组细胞中B细胞淋巴瘤2(Bcl-2)、Bcl-2相关X蛋白(Bax)、含半胱氨酸的天冬氨酸蛋白水解酶3(Caspase-3)、含半胱氨酸的天冬氨酸蛋白水解酶9(Caspase-9)、糖原合成酶激酶3β(GSK3β)、β-连环蛋白(β-catenin)和细胞周期蛋白D1(Cyclin D1)蛋白表达水平。结果:TCMSP数据库筛选得到蜂王浆6种活性成分,10-HDA治疗结肠癌核心靶点28个。GO功能富集分析主要涉及细胞增殖和细胞凋亡等信号通路;KEGG信号通路富集分析涉及细胞周期、前列腺癌、细胞衰老和p53等信号通路,GSK3β/β-catenin信号通路与细胞周期有密切关联。与对照组比较,5、10、15和20 mmol·L^(-1)10-HDA组细胞存活率呈剂量依赖性降低(P<0.05或P<0.01)。与对照组比较,不同剂量10-HDA组细胞中凋亡细胞数明显增多,细胞划痕愈合率明显降低(P<0.05或P<0.01),中和高剂量10-HDA组细胞中S期细胞百分率明显升高(P<0.05或P<0.01),不同剂量10-HDA组细胞中T-AOC和SOD活性明显降低(P<0.05或P<0.01)。与对照组比较,低剂量10-HDA组细胞中Bcl-2蛋白表达水平明显降低(P<0.01),GSK3β蛋白表达水平明显升高(P<0.05);与对照组比较,中和高剂量10-HDA组细胞中Bax、Caspase-3、Caspase-9和GSK3β蛋白表达水平明显升高(P<0.05或P<0.01),Bcl-2、β-catenin和Cyclin D1蛋白表达水平明显降低(P<0.01)。结论:10-HDA可明显抑制结肠癌细胞增殖和迁移,并可促进结肠癌细胞的凋亡和氧化水平,其作用机制可能与激活GSK3β/β-catenin信号通路有关。

基于生物信息学方法和免疫组化分析FASN在宫颈癌组织的表达及临床意义

目的 利用生物信息学方法和免疫组化分析脂肪酸合酶(FASN)在宫颈癌(CC)组织中的表达水平及相应的临床意义。方法 从癌症基因组图谱(TCGA)数据库中下载CC患者的RNA测序数据及临床信息,通过R4.2.2提取FASN表达数据,并结合患者的临床特征,探讨FASN在CC组织中的表达水平、与临床特征的相关性以及患者预后的关系。同时,通过基因集富集(GSEA)揭示FASN相关的生物学功能和信号通路。最后,通过免疫组化实验证实了FASN在CC组织中的表达,并分析了FASN表达的免疫组化(IHC)评分与临床特征的相关性。结果 (1) TCGA数据库及本研究的临床标本均证实,与癌旁组织相比,FASN在CC组织中呈现高表达(P<0.001,P=0.028 5),并与淋巴结转移和病理分级显著相关(P<0.001,P=0.029;P=0.012,P=0.047)。(2) FASN在CC患者中表达水平较高者,其总生存期与无进展生存期明显缩短(P <0.001,P <0.001)。(3) FASN表达的IHC高评分组CC患者的身体质量指数(BMI)显著高于低评分组(P <0.001)。(4)HPV感染状态对于FASN表达的IHC评分高低具有显著差异性(P <0.001)。(5) FASN高表达CC患者的基因富集在癌症途径、细胞外基质-受体相关作用、氮代谢、黑色素瘤和肌动蛋白细胞骨架等调节通路。结论 FASN在CC组织中高表达,且与患者淋巴结转移、病理分级、HPV感染状态、BMI和不良预后相关,有望成为诊断CC的新兴生物标志物及治疗靶点。

脂磷壁酸合成酶ltaS基因缺失对产单核细胞李氏杆菌致病性的影响

本文旨在构建脂磷壁酸合成酶ltaS基因缺失株,探讨ltaS基因对产单核细胞李氏杆菌致病力的影响。本研究利用同源重组技术构建产单核细胞李氏杆菌ltaS基因缺失株,通过生物学特性试验探究ltaS基因缺失株对产单核细胞李氏杆菌生长能力和菌体形态的影响,Western blot试验探究亲本株EGDe-prfA、缺失株ΔltaS对InlA和InlB在细菌表面的锚定情况;使用鸡胚成纤维DF-1细胞进行细胞黏附侵袭试验、小鼠RAW264.7细胞进行吞噬试验与巨噬细胞内增殖试验测定ltaS基因对产单核细胞李氏杆菌侵染能力的影响;小鼠脏器细菌载量和小鼠存活试验评估ltaS基因缺失对产单核细胞李氏杆菌致病性的影响。结果显示:利用同源重组技术成功构建产单核细胞李氏杆菌ltaS基因缺失株,生长曲线试验和光学显微镜观察发现ltaS基因不影响产单核细胞李氏杆菌在BHI中正常生长和细菌形态,通过Western blot试验验证ltaS基因缺失导致细菌表面毒力的InlA和InlB锚定量降低。细胞黏附侵袭试验结果表明,ΔltaS对DF-1的黏附率极显著低于亲本株EGDe-prfA(P<0.01)并且侵袭率也极显著低于亲本株EGDe-prfA(P<0.01);吞噬试验结果显示,小鼠巨噬细胞RAW264.7对ΔltaS的吞噬率与亲本株EGDe-prfA相比无显著性差异(P>0.05);而在增殖试验中,ΔltaS在RAW264.7中增殖量与亲本株EGDe-prfA存在显著差异(P<0.05)。小鼠致病力试验结果显示,经ΔltaS感染的小鼠的肝、脾内细菌载量均显著低于EGDe-prfA(P<0.01)并且EGDe-prfA感染后的小鼠96 h内全部死亡,而缺失株ΔltaS感染的小鼠存活率为80%,测定出亲本株EGDe-prfA半数致死量LD 50为1.7×104 CFU,缺失株ΔltaS半数致死量LD 50为7.49×106 CFU。综上所述,ltaS基因缺失显著减少表面InlA和InlB的锚定量,减弱产单核细胞李氏杆菌对DF-1细胞的黏附侵袭能力与RAW264.7内细菌增殖能力,并且降低对小鼠的致病性。