FGF-21与奶牛能量代谢平衡状态的关系

发布时间：2018-04-20 06:17

本文选题：血清FGF-21浓度 + mRNA表达　；参考：《黑龙江八一农垦大学》2015年硕士论文

【摘要】：为了明确在不同能量代谢平衡状态下奶牛血清中成纤维细胞生长因子(FGF-21)浓度、肝脏以及脂肪组织中FGF-21及其受体表达量的变化规律；奶牛能量代谢负平衡特征性指标之间的关系以及FGF-21水平变化可能反映的能量代谢状态作为诊断能量负平衡的特征性分子标记物以及外源性FGF-21对血清FGF-21浓度、FGF-21及受体在肝脏和脂肪组织中表达量的影响。本研究从某千头奶牛场选取选择非妊娠、非泌乳、健康育成奶牛10头，随机分成2组，每组5头。在实验期间，，一组实验牛先饲喂120%能量需求(1.48Mcal/kg)日粮而后再饲喂30%维持能量(0.37Mcal/kg)日粮，另一组先饲喂30%的维持日粮而后饲喂120%能量日粮（NRC标准），血液样品每天采集，并于实验的第14d和第35d采集两组实验动物的脂肪和肝脏样品。检测能量代谢特征性指标(Glu,NEFA,BHBA,TG等)以及肝脏和脂肪组织中FGF-21及其受体表达量；本实验另选取临床酮病奶牛和健康奶牛90头，分为两组，记录其临床资料和理化指标。另外，选择非妊娠、非泌乳奶牛10头，随机分成2组，每组5头，分为对照组（注射生理盐水10ml），实验组（静脉注射FGF-21），于实验开始时在颈静脉留置针内分别注射FGF-21和生理盐水，实验用时16h，实验提前1d埋置静脉针。奶牛提前3d给予120%维持日粮，确保奶牛能量摄入充足。实验结果显示：摄入30%维持能量(0.37Mcal/kg)日粮的实验牛血清FGF-21水平同时显著升高；饲喂120%的维持日粮的实验牛血清FGF-21水平同时显著降低。在实验检测指标中血清FGF-21指标与瘦蛋白(LP)为正相关，与血糖(Glu),β羟丁酸(BHBA)为负相关。在β-羟丁酸指标大于1.6mmol/L时，血清FGF-21水平小于322.38ng/mL。能量缺乏增加了FGF-21在肝脏的生成以及血清FGF-21浓度，与此同时，能量缺乏也提高了肝脏及脂肪组织中PPARα、PPARγ以及βKlotho的表达量。在FGFR中，FGFR1与FGFR2在能量摄入不足时在肝脏及脂肪组织中的表达量升高，而FGFR3和FGFR4在脂肪及肝脏组织中的表达量变化不显著。外源性FGF-21的影响，在血液指标中外源性注射FGF-21使血清FGF-21、胰岛素、β羟丁酸和血尿酸水平出现不同程度的上调。在FGF-21及其受体的mRNA表达研究中，βKlotho与PPARα和PPARγ在注射外源性FGF-21后肝脏及脂肪表达量升高显著。综上所述，奶牛血清中FGF-21与酮体存在负相关关系。血清FGF-21、肝脏及脂肪组织中FGF-21及其受体与能量密切相关并且在奶牛能量代谢平衡状态的调控中发挥作用。FGF-21指标可以作为反映奶牛机体能量代谢状况表明FGF-21指标可作为早期检测、评估或辅助诊断的特征性分子标记物，为今后深入探究能量负平衡的发生机理和新的防治策略奠定了基础。
[Abstract]:In order to determine the changes of FGF-21 concentration in serum and the expression of FGF-21 and its receptor in liver and adipose tissue under different energy metabolic equilibrium. Relationship between characteristics of negative balance of Energy Metabolism in Dairy cattle and Energy Metabolism State of FGF-21 level as a characteristic Molecular Marker for diagnosing negative Energy balance and exogenous FGF-21 in Serum FGF-21 concentration FGF-21 The effect of body expression in liver and adipose tissue. In this study, 10 non-pregnant, non-lactation and healthy dairy cows were selected from a thousand dairy farms and randomly divided into 2 groups with 5 cows in each group. During the experiment, one group was fed 120% energy demand 1.48 Mcal / kg diet and then 30% maintenance energy 0.37 Mcal / kg diet. The other group was fed 30% maintenance diet and then 120% energy diet NRC standard. Blood samples were collected daily. Fat and liver samples were collected on the 14th and 35th day of the experiment. The expression of FGF-21 and its receptors in liver and adipose tissue were detected, and 90 cows with ketosis and healthy cows were selected and divided into two groups to record their clinical data and physical and chemical indexes. In addition, 10 non-pregnant and non-lactating cows were randomly divided into two groups: control group (10 ml saline injection) and experimental group (FGF-21). At the beginning of the experiment, FGF-21 and saline were injected into the jugular vein indwelling needle, respectively. The experiment lasted 16 hours, and the vein needle was inserted 1 day in advance. Cows were given 120% maintenance diet 3 days in advance to ensure sufficient energy intake. The results showed that the serum FGF-21 level of the experimental cattle fed 30% maintenance energy 0.37 mg / kg diet increased significantly, while the serum FGF-21 level of the 120% maintenance diet decreased significantly at the same time. There was a positive correlation between serum FGF-21 and leptin (LP), and a negative correlation between serum FGF-21 and Gluten, 尾 -hydroxybutyrate (尾 -hydroxybutyrate). When 尾 -hydroxybutyric acid index is larger than 1.6mmol/L, serum FGF-21 level is less than 322.38 ng / mL. Energy deficiency increased the production of FGF-21 in liver and the concentration of FGF-21 in serum. At the same time, energy deficiency also increased the expression of PPAR 伪 -PPAR- 纬 and 尾 Klotho in liver and adipose tissue. In FGFR, the expression of FGFR1 and FGFR2 in liver and adipose tissue increased with insufficient energy intake, but the expression of FGFR3 and FGFR4 in fat and liver tissues did not change significantly. The effects of exogenous FGF-21 on serum FGF-21, insulin, 尾 -hydroxybutyric acid and uric acid were up-regulated by exogenous injection of FGF-21. In the study of mRNA expression of FGF-21 and its receptor, 尾 Klotho, PPAR 伪 and PPAR 纬 increased significantly in liver and fat after injection of exogenous FGF-21. In conclusion, there was a negative correlation between serum FGF-21 and ketone body in dairy cattle. Serum FGF-21, FGF-21 and its receptors in liver and adipose tissue were closely related to energy and played an important role in the regulation of energy metabolism balance in dairy cows. FGF-21 could be used as an index to reflect the energy metabolism of dairy cows. FGF-21 index could be used as an early detection index. The evaluation or auxiliary diagnosis of characteristic molecular markers lays a foundation for further exploring the mechanism of negative energy balance and new prevention and treatment strategies in the future.
【学位授予单位】：黑龙江八一农垦大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S823

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