Effect of bovine colostrum on the growth inhibition and differentiation of human leukemic U937 cells

BACKGROUND: Colostrum is the breast milk of female mammals produced within in a short time after giving birth. It is thought to protect neonates from infection as well as to facilitate immune system maturation. In this study the effect of bovine colostrum on the proliferation and differentiation of human leukemic U937 cells was investigated to understand more about its immunomodulatory activity. RESULTS: Human mononuclear cells (MNCs) were stimulated with bovine colostrum (CS) and then filtered to obtain a conditioned medium (CM) (CS‐MNC‐CM). CS‐MNC‐CMs prepared with day 1 to day 4 colostrums inhibited U937 cells by 39.4–64.4%. The expressions of surface markers CD11b and CD14 on U937 cells in the treated groups were 30.6–33.5% and 40.0–42.6% respectively. High levels of cytokines IL‐1β, IFN‐γ and TNF‐α were detected in CS‐MNC‐CMs. CONCLUSION: Evidence indicates that colostrums stimulate human MNCs to secrete cytokines IL‐1β, IFN‐γ and TNF‐α which subsequently inhibit the growth of U937 cells and induce their differentiation into mature monocytes and macrophages. There is a possibility for bovine colostrum to be processed into an anti‐leukemia ingredient for use in health foods. Copyright © 2009 Society of Chemical Industry     

中国北方人初乳、牛初乳、牛常乳、牛血中胰岛素样生长因子-1和神经生长因子含量的比较

目的检测人初乳、集中饲养的新西兰进口荷斯坦乳牛的初乳、常乳和血液中胰岛素样生长因子-1(IGF-1)和神经生长因子(NGF)的含量,比较人初乳和牛初乳、牛初乳和牛常乳以及牛乳和同期采集的血液中IGF-1、NGF的含量。方法采用放射免疫试剂盒测定人初乳、牛初乳、牛常乳和血中IGF-1、NGF的含量,使用SPSS 13.0进行统计分析。结果本研究中测定的人初乳中IGF-1的含量是26.91μg/L,荷斯坦乳牛的初乳、常乳和血清中IGF-1的含量分别是38.40、20.14和37.35μg/L。人初乳中NGF的含量是300.47 ng/L,荷斯坦乳牛的初乳、常乳和血清中NGF的含量分别是69.82、110.37和9.63 ng/L。经统计学分析发现牛初乳和人初乳中IGF-1的含量差异没有显著性,牛初乳中IGF-1的含量高于牛常乳(P<0.05),牛乳中IGF-1的含量与同期血液中IGF-1的含量差异没有显著性。人初乳中NGF的含量高于牛初乳(P<0.05),牛初乳和牛常乳中NGF的含量差异没有显著性,同期牛血中NGF的含量低于牛乳中NGF的含量(P<0.05)。结论本研究发现牛初乳与人初乳IGF-1含量无明显差别,...     

益生菌发酵牛初乳对致病菌抑制作用的研究

研究了益生菌发酵牛初乳对致病性大肠杆菌及幽门螺旋杆菌的抑制作用。结果表明,初乳经益生菌发酵,导致初乳pH值降低,初乳IgG活性也相应降低,在pH值为4.6时,IgG活性仅为初乳的25%。不同益生菌发酵初乳在不同pH值对大肠杆菌及幽门螺旋杆菌均有抑制作用,且嗜酸乳杆菌发酵初乳抑制作用最强,对大肠杆菌的抑制率最高达83.2%,对幽门螺旋杆菌抑菌圈直径最大达17.2mm,达到高度敏感,分别较初乳的抑制作用提高47.52%和52.21%。不同益生菌发酵初乳的抑菌作用依次为嗜酸乳杆菌>双歧杆菌>混合乳酸菌>德氏乳杆菌保加利亚亚种>嗜热链球菌。     

初乳中生物活性物质的开发与应用

初乳不同于常乳，它是哺乳动物为自己的后代准备的第一份食品。牛初乳不仅含有哺乳动物所必需的各种营养物质、矿物元素和氨基酸，还含有很多具有生物活性的多肽、底聚糖类物质。其中研究较多的有：非肽类营养因子（nonpeptide trophic factors），激素（hormones），细胞因子（cytokines），生长因子（growth factors），表皮生长因子受体配基家族（epidermal growth factor receptor ligand family），表皮生长因子（epidermal growth factor），转移生长因子（transforming growth factor），转化生长因子β家族（transforming growth factor β family），胰岛素样生长因子（insulin-like growth factors），生长调节素及其结合蛋白（somatomedins，and their binding proteins），血小板衍生的生长因子（platelet-derived growth factor），（vascular endothelial growth factor），乳铁蛋白（lactoferrin），生长激素及其释放因子（growth hormone and its releasing factor）和抗体等。本文就初乳的特性、这些生理因子的作用、应用、分离提纯和研究进展进行系统综述，并从哺乳动物进化的角度分析初乳这些功在新生个体发育和分化和先天免疫中的作用。     

膜分离牛初乳中乳铁蛋白的工艺参数研究

研究采用膜分离技术分离牛初乳中乳铁蛋白的工艺条件,并摸索出膜污染的解决办法。以牛初乳为原料,采用单因素试验和二次通用旋转组合设计法优化膜分离乳铁蛋白的工艺条件,并进行响应面分析,比较水法、碱法和水法结合碱法清洗膜的方法。结果显示:提取乳铁蛋白的最适温度38℃、操作压力0.19 MPa、pH 6.9。在此条件下得到膜通量53.2 L/m2.h,膜效能0.79 g/m2.min。膜清洗采用水洗10 min,0.5 mol/L NaOH与4%NaClO混合液清洗15 min,膜通量恢复率可以达到95%以上。     

Epidermal growth factor and hepatocyte growth factor receptors collaborate to induce multiple biological responses in bovine mammary epithelial cells

The aim of this work was to explore whether epidermal growth factor (EGF) and hepatocyte growth factor (HGF) could increase the biological responses of a mammary epithelial cell line of bovine origin when added simultaneously. We also investigated a possible molecular mechanism underlying this cooperation. The development of mammary gland requires several circulating and locally produced hormones. Hepatocyte growth factor and its tyrosine kinase receptor, mesenchymal-epithelial transition factor (MET), are expressed and temporally regulated during mammary development and differentiation. Epidermal growth factor receptor and its ligands have also been implicated in the growth and morphogenesis of the mammary epithelium. Both EGF and HGF seem to exert a morphogenic program in this tissue; therefore, we hypothesized that these cytokines could act cooperatively in bovine mammary epithelial cells. We have already shown that the bovine BME-UV cell line, a nontumorigenic mammary epithelial line, expresses both MET and EGF receptor. Simultaneous treatment with HGF and EGF elicited an increase in proliferation, dispersion, degradation of extracellular matrix, and motility. Following EGF treatment, BME-UV mammary cells exhibited an increase in MET expression at both the mRNA and protein levels. Long-term treatment of BME-UV cells with HGF and EGF together increased the level of activation of the extracellular signal-regulated kinase 1/2 and protein kinase B signaling pathways when compared with HGF or EGF alone. These data outline a possible cooperative role of the EGF and HGF pathways and indicate that cross-talk between their respective receptors may modulate mammary gland development in the cow.     

牛初乳制品功能性成分的分析

利用牛初乳中的免疫球蛋白活性因子，开发具有独特生理功能的乳制品成为牛初乳利用的热点。本研究利用十二烷基硫酸钠-聚丙烯酰胺电泳法和酶联免疫吸附法对市售的牛初孔制品的质量进行了分析与评价。结果表明，目前牛初乳制品的蛋白含量与组成有很大的差异，并且活性免疫球蛋白含量较低。目前牛初乳制品存在的问题亟待解决，市场亟待规范。     

基于超滤法从牛初乳中分离胰岛素样生长因子- Ⅰ的工艺条件

利用超滤技术从牛初乳中分离IGF-Ⅰ,并对脱脂和超滤条件进行优化。IGF-Ⅰ的质量浓度检测采用放射免疫法测定,总蛋白质量浓度采用考马斯亮蓝法测定。结果表明：牛初乳中分离IGF-Ⅰ过程中制备脱脂乳最适工艺条件为36℃、4000r/min 离心15min;经截留分子质量为10～20kD 的中空纤维膜超滤除杂蛋白和6kD 的中空纤维膜超滤去除乳糖等小分子物质,所得的IGF-Ⅰ的纯度浓度较初乳中提高了约3660 倍。本方法确立了从牛初乳中分离纯化较高纯度IGF-Ⅰ的技术路线。     

Composition and clinical use of bovine colostrums

In recent years, a large number of the researches giving fuller picture about structure and properties of bovine colostrums (BC), that allows to apply it at various diseases in clinical practice was carried out in the world. The critical analysis of the modern literature showed bovine colostrums is rich with immunoglobulins, antimicrobials and growth factors in comparison with nature milk. The positive effect of supplementation of bovine colostrums in diarrhea in persons with immune-deficiency syndromes, for treatment NSAID-induced gastrointestinal disturbances, at postoperative responses and in treatment of upper respiratory infection is supposed.     

Lack of effect of epidermal growth factor treatment in late-pregnant ewes on subsequent lactation

Twin-bearing ewes were treated with epidermal growth factor (EGF) to determine its effect on mammogenesis and resultant milk production and composition. The EGF was infused intravenously at a dose rate of 0.5 mg/d in 300 ml saline between days 117 and 139 of gestation; control animals received placebo infusions of saline. All animals then received continuous infusions of 300 ml/d saline on days 139-144. Following parturition 1-5 d later, ewes were milked by hand for 10 d and thereafter were machine-milked until day 16 of lactation. At this level of treatment, EGF was not detected in the circulation during infusion and feed intake was not affected. All ewes gave birth to healthy twin lambs. There were no effects of EGF on birth weights of lambs, live weights of ewes or lengths of gestation. An EGF-immunoreactive material was detected in the mammary secretions of control ewes at a mean concentration of 2 micrograms/l on day 1 of lactation. Two ewes had detectable levels on day 2, but none was found in the milk thereafter. In the EGF-infused group, concentrations of EGF in colostrum were approximately 10 times higher than in the control ewes on day 1 of lactation and EGF was detected in mammary secretions on day 2 but not in subsequent milk samples. A range of 0.3-0.5% of the EGF infused appeared in mammary secretions over the first 2 d of lactation. No other differences were observed for colostrum composition, subsequent milk yield or composition between the two groups of ewes indicating that mammary gland development and function were unaffected. The levels of EGF observed in the mammary secretions of treated and control ewes indicate that the mammary glands accumulate and store EGF in the pre partum period.     

Possible mechanism for acceleration of meiotic progression of bovine follicular oocytes by growth factors in vitro

The mechanism for the accelerating effects of epidermal growth factor (EGF) and insulin-like growth factor I (IGF-I) on the meiotic cell cycle of bovine oocytes cultured in vitro was investigated. Cumulus-oocyte complexes (COCs) were obtained from small (< or = 3 mm in diameter), medium (4-6 mm in diameter) or large (7-10 mm in diameter) ovarian follicles and cultured with or without a combination of EGF and IGF-I (growth factors). Growth factors significantly increased the frequency of first polar body extrusion of oocytes derived from small follicles at 16 h of culture (PB16 oocytes; with growth factors: 75%; without growth factors: 55%), but did not increase the frequency in oocytes from medium or large follicles. COCs from small follicles were cultured with individual growth factors and sampled for kinase activity. The frequencies of polar body extrusion in EGF only (67%) and EGF + IGF-I (75%) treatment groups were significantly higher than those in the control (no growth factor) group (49%), but not significantly higher than in the IGF-I only group (63%). The H1 kinase activity at 6-8 h of culture in each group increased significantly from the baseline value at 0 h of culture, and the H1 kinase activities in the EGF only, IGF-I only and EGF + IGF-I treatment groups were significantly higher than those in the control group at 8 h of culture. MAP kinase activity was significantly higher than the baseline value and significantly higher than that in the control group at 6 h of culture in the EGF treatment group only. In conclusion, EGF and IGF-I act on COCs from small follicles to accelerate the meiotic cell cycle of the oocytes. This accelerating effect may be related to increased H1 and MAP kinase activities during the early stages of maturation.     

发酵法去除牛初乳中酪蛋白提高IgG含量的研究

利用乳酸菌发酵牛初乳从而降低pH达到酪蛋白等电点,通过离心去除酪蛋白,提高免疫球蛋白G(JgG)含量。结果表明,发酵法去除酪蛋白的最适pH为4.65,离心条件为1500×g,30min;随着pH的下降,酪蛋白被去除.初乳中的IgG含量上升,pH由4.70降低到4.65时,IgG含量有显著性变化(P<0.01)。2-7d原料初乳中IgG含量平均为20.09mg/g,经发酵后乳清IgG含量提高约1.5倍,平均达到52.07mg/g。     

高压脉冲电场加工牛初乳的研究

探索了利用高压脉冲电场处理牛初乳的可行性,对以高 压脉冲电场不同加工参数处理的牛初乳样品进行主要微 生物(细菌总数、大肠菌群、霉菌和酵母)的检测,并检测 其中功能性成分IgG含量,与未经处理的牛初乳中IgG 含量对比,证明了用高压脉冲电场加工技术处理牛初乳 的可行性,并确定了较适合的工艺条件。     

响应面法优化牛初乳免疫球蛋白热保护剂的配方

为筛选一种最佳的牛初乳免疫球蛋白（Immunoglobulin G,IgG）热保护剂,以牛初乳为原料对其IgG进行提取,在单因素实验基础上,以IgG活性保留率作为响应值,选取甘氨酸、麦芽糖醇和菊粉三种物质作为响应因子,采用Box-Behnken响应面法对IgG热保护剂配方进行优化,并通过傅里叶变换红外光谱和内源性荧光光谱表征不同方式处理的牛初乳IgG结构。结果表明,IgG热保护剂的最佳配方:甘氨酸0.48%,菊粉14.98%,麦芽糖醇12.50%,在75 ℃,5 min条件下热处理的IgG活性保留率为36.59%,各因素添加量对IgG活性保留率的影响主次顺序均为:麦芽糖醇>甘氨酸>菊粉。傅里叶变换红外光谱和内源性荧光光谱分析结果表示:与未添加复合热保护剂的牛初乳IgG相比,添加复合热保护剂后的牛初乳IgG,β-折叠含量显著下降（P<0.05）,无规则卷曲含量显著下降（P<0.05）,二级构象呈现较为有序的状态;荧光强度降低,IgG分子堆积更加紧密,结果表明添加复合热保护剂后的牛初乳IgG结构稳定性有所提高。本研究探索出一种新型牛初乳IgG的复合热保护剂配方,为牛初乳功能性食品的进一步开发和利用提供了参考。     

Effects of epidermal growth factor,interleukin 1 and nitric oxide on prostaglandin production by guinea-pig uterus

Initial experiments in the present study investigated the effects of epidermal growth factor (EGF), interleukin 1beta (IL-1beta) and sodium nitroprusside (a nitric oxide donor) on the output of prostaglandins from guinea-pig uterus on day 7 of the oestrous cycle. Superfusion of day 7 guinea-pig uterus in vitro with either EGF or sodium nitroprusside increased the output of PGF(2alpha) and 6-keto-PGF(1alpha), but not of PGE(2). IL-1beta had no effect on the output of these three prostaglandins. EGF still increased the output of PGF(2alpha), but did not increase the output of 6-keto-PGF(1alpha) in a calcium-depleted superfusate. Subsequent experiments investigated the effect of sodium nitroprusside on contractile activity of day 7 guinea-pig uterus. Basal spontaneous activity of both the intact uterus and isolated myometrium superfused in vitro was low. Sodium nitroprusside increased the contractile activity of these tissues two- to fourfold. EGF did not affect the contractile activity of the uterus, indicating that sodium nitroprusside-induced contractions are not due to increased prostaglandin production. Overall, the findings indicate that EGF and nitric oxide may act as mediators in the mechanism by which oestradiol acting on a progesterone-primed uterus stimulates the increase in PGF(2alpha) production by the guinea-pig uterus necessary for luteolysis. Nitric oxide may increase the spontaneous activity of the uterus when this activity is low.     

牛初乳中类胰岛素生长因子的提纯研究

本文研究了从牛初乳中用中空纤维超滤膜分离纯化牛初乳类胰岛素生长因子(IGF-I与IGF-Ⅱ),并利用放射免疫测定法(RIA)测定IGF-I与IGF-Ⅱ的浓度。结果表明:在碱性条件下超滤有利于提高类胰岛素生长因子的回收量。     

牛初乳原料杀菌和酸奶加工研究

通过添加稳定剂提高牛初乳的热稳定性并将其加工成酸奶。牛初乳中按0.5 g/100g添加Na2HPO4,65℃加热,记录凝固时间及评价杀菌效果;确定葡萄糖和蔗糖的添加比例,将杀菌初乳制成酸奶,进行乳酸菌和杂菌计数。结果表明,添加Na2HPO4的牛初乳加热40 min才开始凝固,而未添加组加热6 min完全凝固。65℃加热15 min,牛初乳菌落总数和大肠菌群均合格;当葡萄糖添加量为3 g/100g,蔗糖添加量为4 g/100g时,牛初乳酸奶口感最佳,乳酸菌数为1.26×106 cfu/mL。因此按0.5 g/100g添加Na2HPO4可以显著提高牛初乳的热稳定性,加工制成的初乳酸奶兼具了牛初乳和酸乳的双重功效。     

乳铁蛋白的分离及纯化

乳铁蛋白 (Lactoferrin ,简称Lf)作为一种糖蛋白 ,主要存在于哺乳动物的各种外分泌物中 ,如乳汁、眼泪等 ,乳汁尤其是初乳中Lf的含量很高[1] 。Lf是一种多功能蛋白质 ,不仅具有广谱的抗菌作用 ,而且还能够增强机体的抗病毒、抗感染、抗肿瘤的能力和免疫能力。因此 ,从来源丰富的牛初乳中提取出Lf,把它作为功能性成分应用于食品行业 ,具有广阔的应用和开发前景。本文通过盐析法和层析法从牛初乳中分离出乳铁蛋白 ,并应用酶联免疫法 (ELISA)检测不同分离纯化方法所获得的乳铁蛋白的含量 ,并用电泳分析其纯度。所获得的乳铁蛋白的分子质量为 780 0 0u ,其纯度大约为 92 %。     

HPLC法检测牛初乳中lgG含量

建立了牛初乳中IgG的高效液相色谱检测法,并测定了 初乳中IgG的经时变化过程。结果显示,IgG浓度在0.2～ 15mg/mL的范围内峰面积与浓度呈现良好的线性关系, 回收率实验平均大于98.5％。采用本法测定了六头幽门螺 杆菌免疫牛初乳中IgG及两头正常牛初乳中IgG的经时 变化过程。母牛分娩后24h内,初乳中免疫球蛋白IgG平 均含量在40～70mg/mL之间;3d后,初乳中免疫球蛋白 总量下降较快;至第7d,初乳中免疫球蛋白含量平均在 1～5mg/mL之间。