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中药调节细胞凋亡机理的研究进展 总被引:1,自引:0,他引:1
细胞凋亡是一种细胞自杀行为,又称程序性细胞死亡。其机制涉及到一系列基因的激活表达和调控。本文从中药及其有效提取物制剂对细胞DNA复制、细胞凋亡途径、凋亡信号传导、凋亡相关基因表达、细胞因子的影响等方面,对中药调节细胞凋亡的作用机理做一综述。 相似文献
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应用特异性方法检测转化生长因子(TGF-β1)对奶牛乳腺上皮细胞增殖和凋亡的作用,用不同浓度的TGF-β1作用于体外培养的奶牛乳腺上皮细胞,在不同时间收集培养细胞及其培养液,应用MTT法检测细胞增殖、应用分光度法检测caspase-3活性、测定DNA片段化率法检测细胞凋亡。结果表明,1、5、10ng/mL TGF-β1试验组与对照组比较细胞增殖差异显著(P<0.05),随TGF-β1浓度增大抑制细胞增殖作用增强。细胞凋亡检测显示,1、5、10ng/mL TGF-β1试验组与对照组比较细胞凋亡差异均显著(P<0.05),随TGF-β1浓度增大促进细胞凋亡作用增强。TGF-β1可以抑制奶牛乳腺上皮细胞的增殖,促进奶牛乳腺上皮细胞凋亡。 相似文献
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《畜牧与兽医》2016,(11):32-37
本试验采用12头泌乳中期的荷斯坦奶牛,随机分为两组,每组6只。其中一组饲喂低精料日粮,即日粮中含有40%的精料和60%的粗料,精粗比为4∶6,作为对照(LC)组;另外一组饲喂高精料日粮,精粗比为6∶4,作为试验(HC)组。试验周期为18周,试验开始前为所有奶牛安装瘤胃瘘管,试验后期采集瘤胃液,乳动脉、静脉血和乳腺组织样品,测定瘤胃液p H值和LPS含量、血浆中LPS含量、乳腺组织细胞中凋亡相关基因如caspase-3、caspase-8、caspase-9、bax和bcl-2等的表达、凋亡相关蛋白酶的活性和NF-κB通路中的蛋白表达。结果显示:长期高精料饲喂使奶牛瘤胃p H值均值降低,一天中p H值低于5.6的时间超过3 h;高精料组血浆和瘤胃液中LPS含量均极显著高于低精料组(P0.01);高精料组caspase-3的基因表达显著高于低精料组(P0.05),而bcl-2的基因表达显著低于低精料组(P0.05);高精料组caspase-3和caspase-8的酶活性相比于低精料组都显著升高(P0.01);高精料组NF-κB p65和磷酸化的NF-κB p65的蛋白表达量均显著高于低精料组(P0.05)。 相似文献
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The role of IGFBP-5 in mammary gland development and involution 总被引:2,自引:0,他引:2
Insulin-like growth factor-I (IGF-I) plays an important role as a survival factor during mammary gland development and remodelling during involution of the mature/lactating mammary gland, and elevated concentrations have been associated with increased risk of breast cancer. The actions of IGF-I are modulated by a family of binding proteins (IGFBPs) and we have shown that IGFBP-5 is associated with cell death in the mammary gland and more recently provided the first evidence that it is causally related to apoptosis of the mammary gland. A transgenic mouse expressing IGFBP-5 on a mammary-specific promoter led to impaired mammary development involving inhibition of IGF-signalling and involving members of the Bcl-2 family. Subsequent studies in vitro and in vivo using exogenous IGFBP-5 treatment have added support to this concept. Although the effects of IGFBP-5 did appear to involve inhibition of IGF action, a role for IGF-independent effects cannot be ruled out. Such IGF-independent effects involve potential interactions with components of the extracellular matrix involved in tissue remodelling including plasminogen activator inhibitor-1 (PAI-1). In addition, intracellular events involving nuclear localisation of IGFBP-5 have been shown to have the ability to inhibit cell proliferation. Thus, IGFBP-5 seems important for regulating both apoptosis and cell proliferation in the mammary gland during development and post-lactation involution. 相似文献
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Morphologic changes developing during bovine mammary involution were examined. Quarter biopsy specimens were obtained weekly from 5 cows beginning the day milking was discontinued through parturition. Light and electron microscopic examination of mammary tissue indicated a gradual reduction in synthetic and secretory activity of alveolar epithelium as involution progressed. Light microscopic morphologic analysis revealed increases in stroma and nonactive secretory epithelium, with concomitant decreases in epithelium, lumen, and fully active secretory epithelium during the first 2 weeks of involution. Electron microscopic analysis of alveolar epithelium revealed decreased number of organelles associated with milk synthesis and secretion during this time. These changes reversed gradually beginning 2 weeks before parturition, and by the time of calving, cell structure was typical of lactating glands. Tissue from infected quarters had less synthetic and secretory ability as indicated by significantly higher percentages of stroma and nonactive cells, but lower percentages of lumen and moderately active cells, compared with uninfected quarters. Infected quarters also had more leukocytes infiltrating the epithelium, lumen, and stroma, compared with uninfected quarters. Microscopic examination of macrophages and neutrophils suggested these cells removed milk components and cellular debris during involution. Large numbers of plasma cells, with distended cisternae of rough endoplasmic reticulum, suggested local antibody production during the periparturient period. 相似文献
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乳腺是哺乳动物特有器官之一,其发育可分为胚胎期、青春期、妊娠期、哺乳期和退化期共5个阶段,发育过程主要受激素、生长因子及细胞因子等调控。乳腺发育主要在出生后,青春期经生长激素(growth hormone, GH)、雌激素(estrogen, E)和胰岛素样生长因子1(insulin-like growth factor 1, IGF1)等调控启动分支形态发生;妊娠期及哺乳期由孕激素(progesterone, P)和催乳素(prolactin, PRL)共同作用产生腺泡并分泌乳汁;退化期则由断奶启动退化过程,腺体重塑至妊娠前状态。乳腺功能主要是通过产生和分泌乳汁以维持初生幼畜正常发育,研究乳腺发育调控机制对畜牧生产具有重要意义。本文以小鼠为例介绍其乳腺发育过程及发育调控机制,并阐述研究乳腺发育及人工调控乳腺发育对畜牧生产的深刻意义,为后期进一步研究乳腺发育和初乳形成提供一定理论参考。 相似文献
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The role of neutrophil apoptosis in the resolution of bovine mammary gland injury induced by intramammary administration of physiological buffered saline (PBS) or lipopolysaccharide (LPS) was investigated. Twenty mammary glands of five non-pregnant heifers were used in the two studies and each animal received both stimuli. Samples of cell populations were collected by mammary gland lavages before and 24, 48, 72 and 96 hours after treatment and examined by light microscopy and staining for myeloperoxidase (MPO). A marked influx of neutrophils into the mammary gland was observed 24 hours after stimulation. At the same time, apoptotic neutrophils and MPO-positive macrophages (MAC) were identified in the samples. The numbers increased to reach maximum values at 48 hours after stimulation with PBS and at 72 hours after stimulation with LPS. The observed differences in the length of the resolution period indicate that neutrophil viability can be modulated by delaying the apoptotic process. Apoptosis of neutrophils and their subsequent phagocytosis by MAC can be regarded as a significant mechanism in the removal of neutrophils from the acutely injured mammary glands and, hence, in the resolution of bovine mastitis. 相似文献
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Jen YF Lee WM Lin CC Cheng YH Wang JH Kuo TF Chang MH 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(5):437-441
Carbonic anhydrase (CA), a metallo-enzyme containing zinc, broadly distributes in mammalian tissues and participates in physiological regulation such as respiration, acid-base balance, ion transport, bone resorption, as well as the development of tumor by the reversible hydration of carbon dioxide. However the expression of CA in the tissue of mammary gland tumor was not documented. In this study we examine the histolocalization and gene expression of CA in both normal canine mammary gland tissue and mammary gland tumor by histochemical examination, and RT-PCR. Four mRNA expression of CA isoenzymes, such as CA II, IV, VI and IX were found under RT-PCR analysis and different band patterns were found between normal canine mammary tissue and canine mammary gland tumor tissue. CA II, IV, VI and IX gene mRNA expression were found in the normal mammary gland tissue, indicating CA II, IV, VI and IX are likely to be the essential enzymes to maintain the normal physiological condition of canine mammary gland tissue cells. However the expression of CA IV was not found in the tissue of malignant mammary gland tumor that may become the marker for the prognostic recognition of canine mammary gland tumor. 相似文献
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Mammary secretions from 12 Holstein dairy cows were collected to evaluate growth inhibition of Escherichia coli and Klebsiella pneumoniae during involution and during physiologic transitions of the mammary gland. Mammary secretions obtained during late lactation poorly inhibited growth of E coli and K pneumoniae. However, as involution progressed, mammary secretions increasingly inhibited growth of both coliform mastitis pathogens. Greatest inhibition of E coli and K pneumoniae growth was observed when mammary glands were fully involuted. Growth inhibition remained high until 7 days before parturition, and then it decreased significantly (P less than 0.05) to that observed during late lactation. Inhibition of coliform mastitis pathogen growth was associated with high concentrations of lactoferrin and immunoglobulin G, decreased citrate concentration, and a low citrate to lactoferrin molar ratio. These data suggested that differences in susceptibility or resistance to new intramammary infection with coliform mastitis pathogens during the nonlactating period may be attributable, in part, to marked changes in mammary secretion composition that develop during physiologic transitions of the mammary gland. Resistance of the fully involuted mammary gland to coliform infection may be associated with high concentrations of natural protective factors. 相似文献
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Cywińska A Baś M Karpiuk O Krzyzowska M Rzewuska M Schollenberger A Niemiałtowski M 《Polish journal of veterinary sciences》2006,9(1):63-70
Mastitis remains a major cause of economic losses in dairy herds. It is believed, that the enhancement of natural defense mechanisms in mammary gland may be helpful in the treatment of bovine mastitis. Our study was designed to assess the apoptosis of leukocytes isolated from bovine milk during subclinical staphylococcal mastitis. Milk samples were collected from cows naturally infected with one pathogen--Staphylococcus aureus and from animals with mastitis caused by several pathogens, including S. aureus. It has been determined that the rate of apoptosis was lower in mastitic milk, as compared with control samples, although varied significantly between groups. High percentage of apoptotic cells was detected in milk with high counts of pathogenic bacteria. In all groups the rate of apoptosis was dependent on the bacterial load, although various correlations were identified. Thus, it is postulated, that the rate of apoptosis of somatic cells in mastitic milk is related to the etiology of infection and is determined by the bacterial load. 相似文献
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G E Thompson 《Research in veterinary science》1988,44(2):175-177
Measurements have been made of the concentrations of triglycerides, free fatty acids, sodium, chloride and potassium in milk samples obtained from cows during acute mammary involution and after parturition. Free fatty acid levels in milk increased more than 10-fold during involution. Their appearance did not immediately follow the cessation of milking but followed the increase in permeability of the mammary epithelium, evidenced by changes in the electrolyte content of the milk, that occurs after a delay of a few days. However, the concentration of free fatty acids did not remain high throughout the dry period but had declined to low levels before the change in permeability was reversed at the next parturition. It is concluded that the high level of free fatty acids in milk during mammary involution does not result from equilibration with an extra-mammary pool, but most likely arises from breakdown of triglycerides remaining in the gland which may be accelerated in some manner by the increase of permeability of the mammary epithelium. 相似文献
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Changes in surface proteins of leukocytes in bovine mammary secretions were examined during mammary involution. Leukocytes were collected from mammary secretions from involution days (ID) 1 to 36 and were labeled with biotin. Labeled proteins were separated by polyacrylamide-gel electrophoresis, transferred to nitrocellulose by protein blotting, and detected with avidin-peroxidase and color reagent. The population of leukocytes in mammary secretions changed during involution from predominantly polymorphonuclear leukocytes (PMN) at ID 1 to predominantly mononuclear leukocytes by ID 36. The gel profile of surface proteins also changed during involution, and some of those changes may have been caused by shifts in leukocyte populations. Profiles of surface proteins of leukocytes from mammary secretions containing predominantly PMN (ID 1) were different from profiles of PMN from blood. A distinctive change in the pattern of surface proteins on the leukocytes occurred between ID 1 and 3, even though the proportion of PMN did not change appreciably between those days. 相似文献