1-辛烯-3-醇对HT22细胞的神经毒性

1-辛烯-3-醇是食用菌中的典型风味物质，已有研究发现其对于大脑神经系统有一定的损伤。本研究拟从细胞凋亡、氧化应激、能量代谢和炎症指标等方面研究不同剂量（0（对照组）、0.025%（体积分数，后同）、0.050%、0.075%、0.100%、0.125%、0.150%）1-辛烯-3-醇对HT22细胞的神经毒性。结果表明：剂量高于0.050%的1-辛烯-3-醇明显能降低HT22细胞活力，并引起脑源性神经营养因子mRNA相对表达水平下降，从而引起中枢神经系统的损伤；而细胞凋亡率、凋亡基因Bax/Bcl-2 mRNA相对表达水平、活性氧相对含量、超氧化物歧化酶活力和丙二醛含量增加；同时引起线粒体膜电位的下降及细胞色素c氧化酶质量浓度的增加；另外，促炎细胞因子肿瘤坏死因子-α、白细胞介素-6的mRNA相对表达水平也增加。综上，1-辛烯-3-醇通过以上几个方面共同调控，以介导对HT22细胞的神经毒性损伤，本研究可为1-辛烯-3-醇的神经毒性研究提供理论依据。     

人参叶多酚GLP-8调控AhR/NLRP3信号通路抑制BaP诱导的气道上皮细胞炎症因子过表达

基于活性追踪方法分离人参叶多酚化合物（Ginseng leaf polyphenols,GLPs)并研究其抗环境污染物苯并芘（Benzo(a)pyrene,BaP）诱发气道上皮细胞（16HBE）氧化、炎症损伤的作用机制。最终分离、鉴定11个人参叶多酚化合物GLP-1~ GLP-11,其中GLP-8（Albaspidin AA,Ginseng leaf polyphenol-8）能够显著抑制BaP诱导的16HBE细胞损伤;相比于BaP组,GLP-8使16HBE细胞活力提升13.90%;GLP-8使BaP诱导的活性氧（Reactive oxygen species,ROS）过量分泌分别降低了19.30%（5 μg/mL）和41.30%（25 μg/mL）;GLP-8使Bap诱导的16HBE细胞凋亡率分别降低5.80%（5 μg/mL）和9.30%（25 μg/mL）;25 μg/mL GLP-8作用后,BaP诱导的炎症因子IL-33、IL-25、IL-1β及IL-6的表达分别减少60.10%、28.90%、33.50%及41.90%;GLP-8抑制芳香烃受体（AhR）及核苷酸结合寡聚化结构域样受体蛋白3（NLRP3）信号通路激活。因此得出,GLP-8具有通过调控AhR/NLRP3信号通路抑制BaP诱导的ROS过量分泌及炎症因子过表达来发挥保护气道上皮细胞活性的功能。     

活性氧的生成与健康和疾病关系研究进展

从历史上看,活性氧（reactive oxygen species,ROS）被认为只引起细胞损伤及生理功能障碍,ROS及其氧化损伤与多种疾病,包括神经退行性疾病、糖尿病、癌症和过早衰老相关。然而,近年来,越来越多的证据显示,ROS对健康至关重要。在生理条件下,低水平ROS的生成被认为是信号分子。另一方面,ROS的过度生成,与ROS缓冲系统的功能障碍相关,会导致慢性疾病的发展。因此,ROS的慢性释放参与许多疾病的发病。而且,ROS生成过量诱导生物分子的氧化损伤,进而导致衰老、癌症和许多其他疾病。ROS已经参与100多种疾病的发生,包括威胁人类健康的重大疾病癌症、心血管疾病、糖尿病、神经退行性疾病（如帕金森病和阿尔茨海默病）、获得性免疫缺陷综合征、中风和衰老的发生。本文综述了氧的出现与需氧真核生物的进化、ROS的种类、ROS的生理病理多效性、机体内主要的ROS、ROS的生成与反应、ROS与线粒体氧化磷酸化、细胞凋亡、免疫防御和炎症、肿瘤等方面的最新进展,鉴于ATP和ROS对生命的重要性,提出,调控线粒体氧化磷酸化实现ATP与ROS生成的平衡将是健康的关键。     

骆驼蓬多糖以自噬途径免疫调节炎症细胞模型

目的：以骆驼蓬多糖干预小鼠腹腔巨噬细胞RAW264.7炎症反应模型,探讨骆驼蓬多糖调节炎症反应的生物活性及意义。方法：利用稳定表达GFP-LC3的NRK细胞,用不同浓度的骆驼蓬多糖干预,诱导细胞自噬,用激光共聚焦显微镜进行观察自噬体,筛选出骆驼蓬多糖诱导细胞自噬的最佳干预浓度和时间范围;利用RAW264.7细胞,以1μg/mL脂多糖构建炎症反应细胞模型;参照骆驼蓬多糖诱导细胞自噬的最佳浓度和时间进行干预,以CCK-8试验检测细胞活性,选择Hoechst和PI双重染色方法观察细胞凋亡,用ELISA试剂检测炎症因子IL-1β和TNF-α的分泌量。结果：骆驼蓬多糖对NRK细胞诱导自噬的最佳时间为12h,浓度为50μg/mL-100μg/mL范围。骆驼蓬多糖干预LPS诱导的RAW264.7细胞炎症模型后,抑制细胞增殖活性,诱导细胞凋亡,呈剂量依赖性,细胞培养液中,TNF-a和IL-1β分泌量降低,与模型组有显著差异(p<0.05)。结论：骆驼蓬多糖能抑制LPS刺激诱导的巨噬细胞增殖,诱导细胞自噬和凋亡,能抑制LPS诱导的炎症因子。     

丙烯酰胺生殖和发育毒性及其生物标志物的研究进展

丙烯酰胺(acrylamide,AA)是含淀粉类食品经过120℃以上高温加热后产生的,有研究表明AA对机体有生殖毒性、发育毒性、神经毒性和基因毒性等,尤其是AA的生殖毒性和发育毒性逐渐引起了人们的广泛关注。在AA的生殖毒性和发育毒性研究中,任何反映生殖系统损伤的指标均可作为AA生殖毒性的生物标志物;同样,所有能反应发育毒性终点的指标均可作为AA发育毒性的生物标志物。随着越来越多的生物标志物的确定,其在安全性评价中也将发挥重要的作用。因此,生物标志物的研究对综合评价AA的生殖毒性和发育毒性有非常重要的意义。本文综述了国内外对AA的生殖毒性和发育毒性生物标志物的研究进展,为AA这两种毒性评价指标的选择提供参考。     

葡萄籽原花青素对顺铂诱导人胚肾细胞凋亡的拮抗作用

目的： 探讨葡萄籽原花青素（ g r a p e s e e d p r o a n t h o c y a n i d i n , G S P E ） 对顺铂（cis-diamminedichloroplatinum,CDDP）诱导人胚肾细胞HEK293凋亡及相关凋亡基因的影响,并探讨可能的机制。方法：体外培养正常HEK293细胞,噻唑蓝法测定GSPE、CDDP分别对HEK293细胞生长的影响以及GSPE对CDDP诱导HEK293细胞毒性的保护作用,流式细胞仪测定GSPE对CDDP所致HEK293细胞凋亡率的变化,Western blotting测定GSPE对CDDP所致HEK293细胞凋亡相关基因Bax、Bcl-2蛋白表达的影响。结果：GSPE对CDDP所致HEK293细胞毒性具有拮抗作用,可减轻CDDP所致HEK293细胞凋亡,减弱Bax表达、增强Bcl-2表达。结论：GSPE对CDDP所致HEK293细胞凋亡具有拮抗作用,其机制可能与GSPE降低促凋亡基因Bax,升高抗凋亡基因Bcl-2的表达有关。     

罗伊氏乳杆菌抑制肠上皮细胞炎症反应和凋亡的作用及机制

目的：探讨罗伊氏乳杆菌对肠上皮细胞炎症反应和凋亡的作用及相关机制。方法：通过免疫荧光和酶联免疫吸附检测罗伊氏乳杆菌对肠上皮细胞炎症反应和凋亡的影响;采用生物信息学分析、定量聚合酶链式反应和双荧光素酶报告基因等实验筛选罗伊氏乳杆菌发挥作用的下游微小核糖核酸（microRNA,miRNA）;通过双荧光素酶报告基因和Western blot等实验筛选miR-196a下游靶基因及其功能。结果：罗伊氏乳杆菌能够抑制脂多糖引起的肠上皮细胞炎症反应和凋亡,进一步分析发现罗伊氏乳杆菌通过上调肠上皮细胞miR-196a抑制细胞炎症和凋亡,miR-196a通过靶向抑制程序性细胞死亡因子4(programmed cell death 4,PDCD4)基因表达发挥对肠上皮细胞的保护作用。结论：罗伊氏乳杆菌通过miR-196a靶向抑制PDCD4基因表达,减缓肠上皮细胞炎症反应和凋亡。     

地参游离酚对CCl4所致肝细胞损伤细胞凋亡、细胞周期及炎症因子的影响

通过体外实验,研究地参游离酚对CCl₄所致肝细胞损伤细胞凋亡、细胞周期及炎症因子的影响。采用流式细胞术分析细胞凋亡及细胞周期的分布,采用试剂盒测定肿瘤坏死因子α（TNF-α）、白介素8（IL-8）的含量和天冬氨酸半胱氨酸蛋白酶3（Caspase-3）活化程度,同时采用免疫组化检测环氧化酶-2（COX-2）、白介素6（IL-6）和诱导型一氧化氮合酶（iNOS）的蛋白表达水平。结果表明,与模型组相比,地参游离酚能显著降低CCl₄引起的细胞凋亡,影响细胞周期的分布,能显著降低炎症因子TNF-α、IL-8的含量并阻滞Caspase-3的活化程度（P<0.05）,并不同程度降低COX-2、IL-6和iNOS蛋白表达水平（P<0.05）。地参游离酚通过抑制细胞凋亡、影响细胞周期分布和抑制炎症反应保护CCl₄所致的肝细胞损伤。     

枸杞环肽调控NLRP3及NF-κB信号通路减轻BaP诱导的气道上皮细胞炎性损伤

该研究通过活性追踪法分离枸杞活性肽（Lycium barbarum L. Bio-active Peptide,LBP）,并研究其抗苯并芘（Benzopyrene,BaP）诱导的气道上皮细胞损伤活性及潜在机制。利用CCK-8法检测LBPs细胞毒性;ELISA法检测LBP-1抑制BaP诱导的人支气管上皮16-HBE细胞炎症因子（TNF-α、IL-1β、IL-6、IL-18、NO和PGE2）的分泌;Western Blot法检测LBP-1及BaP对16-HBE细胞COX-2、iNOS及NLRP3炎症小体和NF-κB信号通路相关蛋白表达的影响。结果显示,LBP-1能显著减轻BaP暴露导致的16-HBE细胞活力降低,且浓度小于1 mmol/L时无显著细胞毒性;LBP-1降低了由BaP暴露导致的细胞炎症因子分泌增加,TNF-α、IL-1β、IL-18、IL-6、NO和PGE2的浓度分别降低了34.93%、27.41%、31.05%、35.28%、51.15%及27.46%,同时PGE2和NO的关键酶（COX-2、iNOS）的表达分别降低了81.72%及41.70%;Western Blot结果显示,LBP-1可抑制IκBα和p65的磷酸化,降低NLRP3及含有Card的凋亡相关斑点样蛋白（Apoptosis-associated Speck-like Protein containing a CARD,ASC）的表达,从而抑制了NLRP3及NF-κB信号通路的激活。以上结果证实LBP-1可通过调控炎性细胞因子及NLRP3、NF-κB信号通路相关蛋白的表达发挥抗BaP诱导的气道上皮细胞炎性损伤的作用。     

Maternal late-gestation metabolic stress is associated with changes in immune and metabolic responses of dairy calves

Metabolic stress in periparturient dairy cows is characterized by excessive lipid mobilization, inflammation, and oxidative stress that is associated with immune dysfunction. Thus, metabolic stress around the time calving is linked to the development of various early-lactation health disorders. Maternal status during late pregnancy can have carryover effects on several health and production variables of neonatal calves. However, the effects of metabolic stress during gestation on metabolic and immune responses of newborn calves remain unknown. Thus, we aimed to investigate whether metabolic stress in late-gestation dairy cows is associated with changes in the metabolic and immune responses of their offspring during the first month of life. Holstein-Friesian cows (n = 12) were blood sampled at 28 and 15 d before expected calving. The average between these 2 sampling points in the serum concentrations of nonesterified fatty acids (NEFA), haptoglobin (Hp), and oxidant status index (OSi)—defined as the ratio between reactive oxygen and nitrogen species and total antioxidant potential—were calculated as indicators of the degree of lipid mobilization, inflammation, and oxidant status (OS), respectively. Calves were subsequently divided into groups (n = 6 each) according to their dams' high or low degree of lipid mobilization, inflammation, and OS. The metabolic responses of calves in each of these groups were compared weekly throughout their first month of life by assessing serum concentration of NEFA, Hp, and OSi. Additionally, whole blood was obtained from calves at each sampling period and subjected to a lipopolysaccharide (LPS)-stimulated tumor necrosis factor-α (TNF-α) production assay to assess cell-mediated innate immunity against induced inflammatory responses, using high (5 μg/mL of blood) and low (10 ng/mL) concentrations of LPS. Calves born to cows with higher NEFA or OSi showed lower body weight at birth and throughout the study, whereas no association between any of the maternal groups and average daily gain at 4 wk of age was identified. Serum concentrations of reactive oxygen and nitrogen species were higher in calves exposed to higher maternal NEFA concentrations or OSi when compared with calves born to cows with lower values of these biomarkers. Calves exposed to high maternal OS also had higher circulating concentrations of Hp and TNF-α, indicating greater basal inflammatory responses when compared with calves born to cows with a lower OSi. In contrast, LPS-induced inflammatory responses were less robust in calves exposed to higher maternal biomarkers of inflammation or OS, suggesting compromised immune responses to microbial agonists. Collectively, these data suggest that prenatal exposure to maternal parameters of metabolic stress may adversely affect some metabolic and inflammatory responses of the offspring that could influence disease susceptibility.     

Effects of metabolizable protein concentration,amino acid profile,and fiber source on the messenger RNA expression of skeletal muscle in peripartum dairy cows

After parturition, dairy cows mobilize AA from skeletal muscle to meet metabolizable protein (MP) requirements. High mobilization may compromise cow health and longer-term milk production. Postpartum diets with higher MP concentrations, improved AA profiles, or MP increased at the expense of forages rather than nonforage fiber sources may attenuate muscle catabolism; however, the molecular mechanisms responsible need investigation. We evaluated mRNA expression in the longissimus dorsi of cows fed postpartum diets differing in MP concentration, AA profile, and fiber source. From 0 to 25 d after parturition, 40 multiparous cows received the following diets: (1) 13% deficient in MP (D-MP), (2) adequate in MP using primarily soy protein (A-MP), (3) adequate in MP using blends of proteins and individual AA to improve the AA profile (Blend), or (4) similar to Blend except additional protein replaced forage (Blend-fNDF). Biopsies were taken approximately ?5, 7, and 25 d relative to parturition. Greater dietary MP concentration (D-MP vs. A-MP and Blend) decreased expression of genes related to protein synthesis (MTOR, RPS6KB1) and degradation (FOXO1), inflammation (IFNG, TLR4), and endoplasmic reticulum (ER) stress (HSPA5, DDIT) and increased genes associated with lipogenesis (PPARG) and glucose oxidation (LDH, MB). In Blend versus A-MP (i.e., effect of AA profile), expression related to apoptosis (CASP8) and inflammation (TNFA) decreased and genes associated with cell cycle progression (E2F1) and fast-twitch glycolytic muscle fiber type (MYH4) increased. Less forage (Blend-fNDF vs. Blend) decreased genes associated with lipogenesis (PPARG, ACACA) and ER stress (BCL2, DDIT3, EIF2AK3, PPP1R15A) and increased genes associated with inflammation (TNF), inhibition of myogenesis (MSTN), and autophagy (PEBP1). In summary and based on mRNA expression, increasing MP supply may attenuate muscle turnover and ER stress. However, an unbalanced AA supply reduced cell cycle progression and protein synthesis. Lower energy supplies may reduce cell growth and cause autophagy.     

Apocynin exerts neuroprotective effects in fumonisin b1–induced neurotoxicity via attenuation of oxidative stress and apoptosis in an animal model

The Fusarium verticillioides produces a mycotoxin, that is, fumonisin b1 (Fb1), which commonly infects corn and agricultural commodities. The Fb1 showed hepatotoxicity, neurotoxicity, and carcinogenicity in animals. Hence, the present investigation aimed to evaluate the effect of apocynin (AP) on Fb1-induced neurotoxic effects and its mechanism in the mice model and cell line. The male Balb/c mice, with the 6.75 mg/kg bwt of Fb1 were injected subcutaneously for 5 days to induce neurotoxicity. A significant elevation of serotonin (5-HT) was observed in mice treated with Fb1 in the whole brain showing biogenic amines may reflect Fb1 neurotoxicity, but the negatively regulated mechanisms were attenuated by the pretreatment of AP. In addition, AP pretreatment normalized apoptotic changes in histology and immunohistochemistry studies. In Western blotting studies, apoptotic genes were upregulated and oxidative stress genes were downregulated due to Fb1 treatment; while treating with AP, these gene expressions were rectified. Further cell cytotoxicity was investigated by MTT and lactate dehydrogenase (LDH) assays in SH-SY5Y cell line. MTT and LDH assays indicated the IC₅₀ value to be 150 µM of Fb1, which was protected by 100 µg of AP. The electron microscopy evaluated the Fb1-induced apoptotic conditions and its cell morphology recovery by AP. These results suggest that nicotinamide adenine dinucleotide phosphate hydrogen oxidase–mediated reactive oxygen species is the primary upstream signal leading to increased Fb1-mediated neurotoxicity in mice. The use of the antioxidant AP reversed the toxin-induced oxidative stress and apoptosis by its antioxidant potency.     

花生四烯酸、二十二碳六烯酸和二十碳五烯酸 在炎症中的作用概述

心脑血管疾病、肿瘤、糖尿病、神经系统疾病、自身免疫等疾病严重危害着人类的生命和健康,并消耗着大量医疗资源。事实上,很多疾病发生和发展的背后都伴随着炎症反应,炎症是众多疾病的病理基础,甚至是导致这些疾病的诱因。炎症本身是机体的防御性反应,但过度的炎症反应和长期慢性炎症会损害机体的稳态。炎症的调节和控制由炎症介质介导,花生四烯酸(arachidonic acid,AA)、二十二碳六烯酸(docosahexaenoic acid,DHA)和二十碳五烯酸(eicosapentaenoic acid,EPA)等长链多不饱和脂肪酸(10ng-chain polyunsaturated fatty acids,LC-PUFAs)的衍生物是一类重要的调控炎症的介质。炎性细胞间的交流和细胞内信号传递与LC-PUFAs有关。AA经环氧酶和脂氧合酶合成的类二十烷酸主要起促炎作用,但有的也有抗炎作用。DHA和EPA在体内起抗炎作用,由它们合成的消退素(resolvins,Rvs)和保护素(protectin,PD)是重要的抗炎活性物质。DHA和EPA还可以干扰炎性细胞内信号传导途径来抑制炎症反应。本文从炎症与疾病的关系、LC-PUFAs的衍生物及其促炎和抗炎机制等方面综述了AA、DHA和EPA在炎症中的作用。     

Kimchi suppresses 7-ketocholesterol-induced endoplasmic reticulum stress in macrophages

The oxidation of low-density lipoproteins (oxLDL) is considered as a key step in the development of atherosclerosis. Oxysterols such as 7-ketocholesterol (7-KC) have been reported to be partially responsible for the cytotoxicity of oxLDL and induce endoplasmic reticulum (ER) stress which eventually causes apoptosis. We aimed to investigate whether ER stress is induced by 7-KC and can be prevented by the kimchi methanol extract (KME) in RAW264.7 macrophage cells. ER stress induced by 7-KC was characterized by the activation of ER stress markers (GRP78, CHOP, and ATF6). ER stress could aggravate macrophage apoptosis, as assessed by caspase-3 activity. ER stress and apoptosis were inhibited by the KME and glutathione (GSH). We conclude that 7-KC causes aberrant ER stress and apoptosis, all of which are inhibited by KME and GSH. The inhibitory expression of ER stress markers highlights its new protective role against oxLDL-induced ER stress, apoptosis, and subsequent atherosclerosis.     

Survey of acrylamide levels in Chinese foods

A survey of levels of acrylamide (AA) in 349 food products obtained from the Chinese market was conducted. AA was determined by an liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. The limit of detection (LOD) and the limit of quantification (LOQ) of the method in four different matrices ranged from 0.8 to 10 µg kg^?1 and from 4.0 to 25 µg kg^?1, respectively. The results from this survey indicated that AA was present in all samples except drinking water and tea. AA contents in different samples varied greatly according to the raw materials and processing conditions. The highest level of AA was found in potato products, with an average level of 1467 µg kg^?1. Preliminary estimates of AA exposure and risk assessment of AA from foods in the Chinese population were performed using a combination of data obtained in the present survey and 2002 dietary consumption survey carried out in 2002 for the Chinese population. The average dietary exposure of AA was estimated to be 0.38 µg kg^?1 body weight day^?1, which is relatively low compared with the result reported by the Food and Agricultural Organization/World Health Organization (FAO/WHO). Furthermore, the margin of exposure for neurotoxicity, reproductive toxicity, and carcinogenicity of AA was calculated to be 1318, 5250, and 787, respectively.     

壳寡糖对过氧化氢诱导肝细胞损伤的改善作用及机制

目的：评估壳寡糖(chitooligosaccharides,COS)对过氧化氢(H₂O₂)诱导肝细胞损伤的改善作用。方法：通过H₂O₂建立L-02细胞氧化应激损伤模型，对活性氧(reactive oxygen species,ROS)、线粒体膜电位以及IL-6、TNF-α等病程相关基因水平进行分析。结果：COS可改善H₂O₂损伤L-02细胞的增殖活力、抑制线粒体膜电位下降和ROS水平升高(P<0.05)。单细胞纳米生化分析结果显示，COS处理可以平衡H₂O₂损伤L-02细胞的ROS水平波动幅度。另外，COS改善了炎症(IL-6、TNF-α)、凋亡(Caspase 3、Caspase 9、Bax、Bcl-2)及氧化应激(Nrf2、HO-1)相关基因转录水平，表现出抗凋亡和抗氧化应激的作用。结论：COS对H₂O₂损伤的L-02细胞具有保护作用，本实验可为COS的应用...