酵母多糖（β-葡聚糖和甘露寡糖）对动物抗病的调控作用研究

发布时间：2018-05-10 07:46

本文选题：酵母多糖 + 抗癌　；参考：《吉林农业大学》2015年博士论文

【摘要】：食药用菌是人类重要的食品、药品资源。研究食药用菌的活性物质机理、作用和前景,对食药用菌的深度开发、推广,从而造福人类具有深远的意义。酵母,作为重要的真菌之一,已有数千年应用历史。现代生物学的发展对酵母有了更深入和广泛的研究和应用。酵母细胞壁富含多糖,成本低廉、供应充足,是应用广泛的真菌多糖。酵母多糖主要成分是葡聚糖和甘露寡糖,具有多种生物活性。研究利用葡聚糖与甘露寡糖可用稀酸水解的化学性质这一要点,成功建立了同时检测葡聚糖与甘露寡糖含量的HPLC方法。本文利用肠道出血综合症(一种危害高产奶牛的毁灭性疾病)和烟曲霉(Aspergillus fumigatus)研究酵母多糖对免疫低下个体的免疫力恢复能力,以及找到相关的免疫标记,建立相关检测体系。这一部分建立了一种实时定量烟曲霉菌PCR检测方法,以定量分析肠道出血综合症中奶牛血液及组织样品内的烟曲霉DNA。第一项研究表明,肠道出血综合症的发生与烟曲霉之间存在正相关。由于烟曲霉具有攻击感染免疫损伤(immunocomprisied)个体的特性,因此,这部分研究进行了一项以绵羊为对象的实验,以验证上述假设,并且检测了真菌多糖在调节先天、后天免疫功能的能力。该研究确认了地塞米松注射处理生长期的绵羊可以建立免疫损伤模型,每日注射地塞米松降低了L-选择素与IL-1β的浓度,而通过添加酵母多糖可以恢复免疫抑制绵羊的L-选择素与IL-1β的基因表达水平。酵母多糖通过提升L-选择素与IL-1β的表达,加强了嗜中性粒细胞的功能,并且抑制凋亡信号,强化嗜中性粒细胞准确到达靶位点的功能,使其有效进入感染部位并杀灭病原体。本文研究了酵母真菌多糖免疫调节功能及其抗肿瘤作用机制。实验中,我们研究了酵母多糖对正常小鼠、免疫抑制小鼠免疫功能的调节作用,进一步利用H22荷瘤小鼠模型研究酵母多糖通过提高免疫系统达到抗癌效果的作用机理。通过统计分析荷瘤小鼠肿瘤重量、免疫器官指数和相关细胞因子含量的变化,探讨其可能的抗肿瘤作用机制。实验结果显示,酵母真菌多糖具有抑瘤作用,并使小鼠体重增加,提高免疫器官指数。环磷酰胺(CTX)是一种烷化剂类抗肿瘤药,对机体免疫力起着一定程度的抑制作用,虽能有效抑制肿瘤,但同时也有很强的副作用,造成CTX组小鼠的免疫器官呈现不同程度的萎缩、相关免疫指标降低,但酵母多糖对因其产生的副作用有明显的调节作用。通过小白鼠的饲喂实验,酵母多糖对小鼠脾脏和胸腺等脏器官有明显的促进作用。真菌多糖可显著提高一系列免疫标记,包括TNF-α、IFN-γ、CRP及IL-6等。这些基因在肠道细胞中的表达(P0.05)。运用ELISA检测了鼠血清的TNF-α,IFN-γ,CRP和IL-6的浓度,统计结果表明这些细胞因子浓度在实验组有显著提高(P0.05)。说明酵母多糖通过促进细胞因子的基因表达来促进机体的免疫调节功能。本研究专门纯化了血样中的嗜中性粒细胞,进而研究真菌多糖对其TNF-α、IFN-γ、CRP及IL-6表达的影响,结果表明,酵母多糖显著提高这些细胞因子的表达(P0.05),并且提高了L-selectin和IL-8R在肠道和嗜中性粒细胞的表达(P0.05),增强了嗜中性粒细胞的吞噬能力。由于所选用的标记的特殊性,表明在先天性免疫和后天性免疫,包括体液和细胞免疫中,酵母多糖通过减少免疫抑制和增强功能性基因的表达来提高免疫细胞的抗癌和抗病能力的作用,为了探讨酵母多糖在体外影响肿瘤细胞活性的抗肿瘤作用,通过对乳腺癌MCF-7细胞和卵巢癌SKOV3细胞的抑制率进行了研究,结果表明酵母多糖对两株癌细胞的增殖具有一定的抑制作用。本研究进行了肉鸡和生猪动物实验,以验证酵母多糖对免疫功能的调节作用在养殖动物的应用效果。烟曲霉的侵染导致肉鸡出现高死亡率高、生长缓慢等现象。烟曲霉的侵染亦导致母猪腹泻、死胎和流产,新生仔猪拉痢并于数天内死亡。而酵母多糖提高了仔猪成活率和断奶体重,降低了母猪繁殖性疾病,增加了产仔数,提高发情率。两组实验中,酵母多糖(葡聚糖和甘露寡糖)的使用缓解了烟曲霉对动物的应激,提高了免疫功能,改善了肉鸡与生猪的生产性能。两个先天性免疫的标记L-selectin(CD62L)和白介素8的受体(IL-8R)在嗜中性粒细胞的表达显著提高,且在烟曲霉菌存在的情况下,差异更加显著。血清中的各细胞因子,包括抗肿瘤因子(TNF)-α、白介素(IFN)-γ、MIP-1β及CD4+/CD8+等指标均有改善。酵母多糖有效提高了动物疫苗抗体的滴度和高滴度的持续性。酵母多糖通过提高免疫能力和抗病能力的作用,为开发新型、环保、无公害养殖动物的大型传染病防治的产品、减少抗生素的滥用用、降低对抗生素的耐药性提供了新的思路。
[Abstract]:Food and medicinal fungi are important food and drug resources of human beings. It is of profound significance to study the mechanism, function and Prospect of active substances of edible and medicinal fungi, to develop and popularize the edible and medicinal fungi in depth and thus benefit mankind. Yeast, as one of the important fungi, has been applied for thousands of years. The yeast cell wall is rich in polysaccharide, low in cost and abundant in supply. It is a widely used fungal polysaccharide. The main ingredient of yeast polysaccharide is glucan and mannan oligosaccharide, which has a variety of biological activity. The HPLC method for the content of chitosan and manna oligosaccharide. In this paper, we used the intestinal bleeding syndrome (a destructive disease of high yield cows) and Aspergillus fumigatus (Aspergillus fumigatus) to study the ability of yeast polysaccharide to restore immunity to immunocompromised individuals, and to find related immune markers, and establish a related detection system. A real-time quantitative method for the detection of Aspergillus fumigatus PCR to quantitatively analyze the first study of Aspergillus fumigatus DNA. in the blood and tissue samples of dairy cows in the intestinal bleeding syndrome shows that there is a positive correlation between the occurrence of intestinal bleeding syndrome and Aspergillus fumigatus. As Aspergillus fumigatus has the characteristics of individuals with attack of immune injury (immunocomprisied), the cause of Aspergillus fumigatus is due to the characteristics of the individual. This part of this study was conducted in a sheep experiment to verify the hypothesis, and to detect the ability of fungal polysaccharides to regulate innate and acquired immune functions. The study confirmed that a sheep with dexamethasone injected during the growth period could establish an immune injury model, and daily dexamethasone was injected to reduce L- selectin and IL-1 beta. The concentration of yeast polysaccharide can restore the gene expression level of L- selectin and IL-1 beta in the immunosuppressed sheep. The yeast polysaccharide enhances the function of neutrophils by enhancing the expression of L- selectin and IL-1 beta, and inhibits the apoptosis signal and strengthens the function of neutrophils to reach the target site accurately, making it effective. The immunomodulatory function of yeast fungus polysaccharide and its anti-tumor mechanism were studied in this paper. In the experiment, we studied the effect of yeast polysaccharide on the immune function of normal mice and immunosuppressive mice, and further used the H22 tumor bearing mouse model to study the resistance of yeast polysaccharide to the immune system. The mechanism of cancer effect was analyzed by statistical analysis of tumor weight, immune organ index and related cytokine content, and the possible anti-tumor mechanism was discussed. The experimental results showed that the yeast fungus polysaccharide had anti tumor effect and increased the weight of mice and increased the immune organ index. Cyclophosphamide (CTX) was a kind of alkane. The antitumor agents of chemicals have a certain inhibitory effect on the immunity of the body, although it can effectively inhibit the tumor, but it also has a strong side effect, which causes the immune organs of the CTX group to present different degrees of atrophy and the related immune indexes are reduced, but the yeast polysaccharide has obvious regulating effect on the side effects produced by it. The mice feeding experiments showed that Yeast Polysaccharides significantly promoted the spleen and thymus organs of mice. Fungal polysaccharides could significantly improve a series of immune markers, including TNF- alpha, IFN- gamma, CRP and IL-6. These genes were expressed in intestinal cells (P0.05). ELISA was used to detect the concentration of TNF- a, IFN-, CRP and IL-6 in rat serum by ELISA. The results showed that the concentration of these cytokines increased significantly in the experimental group (P0.05). It indicated that the yeast polysaccharide promoted the immune regulation function by promoting the gene expression of cytokines. This study purify neutrophils in blood samples, and then studied the effects of Polysaccharide on the expression of TNF- a, IFN- gamma, CRP and IL-6. Yeast Polysaccharides significantly increase the expression of these cytokines (P0.05), and increase the expression of L-selectin and IL-8R in the intestinal and neutrophils (P0.05) and enhance the phagocytosis of neutrophils. The specificity of the selected markers indicates that the yeast is innate and acquired immunity, including humoral and cellular immunity. In order to explore the antitumor effect of yeast polysaccharide on the activity of tumor cells in vitro, the inhibitory rate of breast cancer MCF-7 and ovarian cancer SKOV3 cells was studied. Sugar has a certain inhibitory effect on the proliferation of two cancer cells. This study conducted experiments on Broilers and pig animals to verify the effect of Yeast Polysaccharides on the immune function in cultured animals. The infection of Aspergillus fumigatus led to high mortality and slow growth of broilers. The infection of Aspergillus fumigatus also resulted in sow diarrhoea. In the two experiments, the yeast polysaccharide (glucan and manna oligosaccharide) alleviates the stress of Aspergillus fumigatus and improves the immune function in the two groups of experiments. The production performance of Broilers and pigs was improved. The expression of two innate immune markers L-selectin (CD62L) and interleukin 8 receptor (IL-8R) was significantly increased in neutrophils, and the difference was more significant in the presence of Aspergillus fumigatus. All cell factors in the serum, including anti tumor factor (TNF) - alpha, IFN - gamma, MIP-1 beta The Yeast Polysaccharides effectively improve the titer and high titer of the animal vaccine. By improving the immune and disease resistance, yeast polysaccharides can develop new, environmentally friendly, harmless breeding animals to prevent and control large infectious diseases, reduce the abuse of antibiotics and reduce antibiotics. Drug resistance provides a new way of thinking.

【学位授予单位】：吉林农业大学
【学位级别】：博士
【学位授予年份】：2015
【分类号】：S859.7

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