动物营养学报  2015, Vol. 27 Issue (10): 3146-3154   PDF (1144KB)    
不同剂型丁酸钠对脂多糖应激肉鸡血清生化指标、抗氧化和抗炎功能的影响
鞠婷婷, 郭孝烨, 随佳佳, 肖雪, 占秀安     
浙江大学动物科学学院, 杭州 310058
摘要:本试验旨在研究不同剂型丁酸钠对脂多糖(LPS)应激肉鸡血清生化指标、抗氧化和抗炎功能的影响。饲养试验将1 000羽1日龄岭南黄肉鸡随机分为5组,每组4个重复,每重复50羽。对照组饲喂基础饲粮,试验组在基础饲粮中分别添加500 mg/kg粉剂丁酸钠(NaB)及250、500、750 mg/kg包膜丁酸钠(CNaB),试验为期50 d。应激试验分别从对照组、NaB组以及生长性能最佳组(250 mg/kg CNaB组),每重复随机选6只鸡,按2×3因子试验设计,以应激种类(生理盐水和LPS)和饲粮类型(0、500 mg/kg NaB和250 mg/kg CNaB)作为主效因子,各组1/2鸡只于53、56和59 d腹腔注射大肠杆菌LPS(0.5 mg/kg BW),剩余鸡只则注射等量生理盐水,试验为期10 d。结果表明:1)与生理盐水注射组相比,LPS注射组显著降低了血清中葡萄糖和甘油三酯含量(P<0.05),显著提高了血清尿酸含量(P<0.05)。LPS注射下,NaB组和CNaB组中血清葡萄糖含量均显著高于对照组(P<0.05)。2)与生理盐水注射组相比,LPS注射组显著或极显著降低了血清和肝脏中超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)活性(P<0.05或P<0.01),显著降低了血清过氧化氢酶(CAT)活性(P<0.05);LPS注射下,NaB组和CNaB组血清和肝脏SOD、CAT活性均高于对照组(P>0.05),丙二醛(MDA)含量低于对照组(P>0.05)。LPS注射和饲粮添加丁酸钠对肝脏GSH-Px活性影响存在交互作用(P<0.05),且2种剂型作用效果相类似。3)与生理盐水注射组相比,LPS注射组极显著提高53和59 d血清铜蓝蛋白和白细胞介素-6(IL-6)含量(P<0.01);LPS注射下,NaB组和CNaB组53 d血清铜蓝蛋白含量显著低于对照组(P<0.05)。由此可见,在LPS应激条件下,丁酸钠能改善肉鸡营养代谢,维持机体抗氧化功能,增强抗炎功能,且500 mg/kg NaB和250 mg/kg CNaB(有效含量为75 mg/kg)作用效果基本一致。
关键词丁酸钠     肉鸡     生化指标     抗氧化     抗炎    
Effects of Different Type of Sodium Butyrate on Serum Biochemical Indices, Antioxidant and Anti-Inflammatory Function of Broilers Challenged with Lipopolysaccharide
JU Tingting, GUO Xiaoye, SUI Jiajia, XIAO Xue, ZHAN Xiuan     
College of Animal Science, Zhejiang University, Hangzhou 310058, China
Abstract: The trial was conducted to study on the effects of different type of sodium butyrate on serum biochemical indices, antioxidant and anti-inflammatory function of broilers challenged with lipopolysaccharide (LPS).Feeding trial: a total of 1 000 one-day-old Lingnan yellow broilers were randomly allocated into 5 groups with 4 replicates in each group and 50 broilers per replicate.Broilers in control group were fed a basal diet, the others in experimental groups were fed the basal diets supplemented with 500 mg/kg powder sodium butyrate (NaB), and 250, 500 and 750 mg/kg coated sodium butyrate (CNaB), respectively.The LPS injection experiment was conducted followed a 50-day feeding trial, 72 fifty-day-old female broilers were selected randomly from control, NaB and 250 mg/kg CNaB group with the best growth performance, with 6 broilers per replicate.And they were allotted into a 2×3 factorial arrangement with challenge status (saline or LPS exposure) and feed diet (0, 500 mg/kg NaB or 250 mg/kg CNaB) as main factor for endotoxin exposure test.Half of broilers in each group were injected intraperitoneally with E.coli LPS (0.5 mg/kg body weight)at 53, 56 and 59 d of age, the remaining broilers were injected intraperitoneally with the same amount of saline as the LPS injected group.The trial lasted for 10 days.The results showed as follows: 1) compared with the saline injected group, the content of glucose and riglyceride in serum was significantly decreased in LPS injected group (P<0.05), but the serum uric acid content as significantly increased (P<0.05).The serum glucose content of NaB and CNaB groups injected with LPS was significantly higher than that of control group (P<0.05).2) Compared with the saline injected group, the activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in serum and liver was significantly decreased in LPS injected group (P<0.05 or P<0.01), the serum catalase (CAT) activity was significantly decreased (P<0.05).The activity of SOD and CAT in serum and liver of NaB and CNaB groups injected with LPS was higher than that of control group (P>0.05), but the malonaldehyde content was lower than that of control group (P>0.05).There were a significant interaction between dietary sodium butyrate and LPS injected on liver GSH-Px activity (P<0.05), and the two forms of sodium butyrate exerted an equal effect on antioxidant enzyme activity.3) Compared with the saline injected group, the content of ceruloplasmin and interleukin-6 in serum at the age of 53 and 59 days was significantly increased in LPS injected group (P<0.05).The serum ceruloplasmin content at the age of 53 days of NaB and CNaB groups injected with LPS was significantly lower than that of control group (P<0.05).In conclusion, sodium butyrate can improve the nutrient metabolism, maintain antioxidant function and promote anti-inflammation function, the effects on anti-stress of 500 mg/kg NaB are equal to those of 250 mg/kg CNaB which contains 75 mg/kg effective substance.
Key words: sodium butyrate     broilers     biochemical indices     antioxidant     anti-inflammation    

目前规模化养殖过程中畜禽面临高饲养密度、热应激、转舍、免疫注射和运输等诸多应激因素,往往会引发机体炎症、营养代偿消耗增加和饲料利用率下降等不良影响。如何通过营养调控手段增强畜禽抗应激功能,降低应激造成的养殖损失日益受到关注。相关研究表明,丁酸钠能增强热应激蛋白表达,提高抗氧化功能[1, 2],调控炎性调节经典核转录因子-κB(NF-κB)通路和炎性细胞因子分泌[3]及修复炎症肠道黏膜作用[4],这使得丁酸钠具有重要的潜在抗应激作用。然而,国内外畜禽研究中关于丁酸钠(sodium butyrate,NaB)或包膜丁酸钠(coated sodium butyrate,CNaB)对应激条件下机体抗氧化、抗应激影响的研究较少,且集中在雏鸡或仔猪阶段[2, 5]。因此,本试验以黄羽肉鸡为研究对象,研究NaB和CNaB对肉鸡在脂多糖(LPS)构建的免疫应激下血清生化指标、抗氧化和抗炎功能的影响及其机制,旨在为生产实践提供科学依据。

1 材料与方法 1.1 试验材料

NaB(≥98%),购于厦门新奥牧业有限公司; CNaB(含30%丁酸钠),购于杭州康德权饲料有限公司;大肠杆菌脂多糖(E.coli LPS),大肠杆菌血清型为O55 ∶ B5,购于美国Sigma公司,现用现配,用灭菌生理盐水配成浓度为500 μg/mL的注射液。

试验动物为1日龄岭南黄羽肉鸡;试验基础饲粮参考我国农业行业标准(NY/T 33—2004)《鸡饲养标准》配制,基础饲粮组成及营养水平见表1。

表1 基础饲粮组成及营养水平(风干基础) Table 1 Composition and nutrient levels of basal diets (air-dry basis)
1.2 试验设计与饲养管理 1.2.1 饲养试验

选取1 000羽1日龄健康岭南黄羽肉鸡,按照单因子完全随机化试验设计,分为5个组,每组4个重复,每重复50羽(公母各占1/2)。对照组饲喂基础饲粮,试验组在基础饲粮中分别添加500 mg/kg NaB及250、500、750 mg/kg CNaB,试验为期50 d。肉鸡自由采食,充足饮水,并进行常规饲养管理及正常免疫程序。

1.2.2 应激试验

在上述饲养试验结束时,从对照组、500 mg/kg NaB组和生长性能最优组(250 mg/kg CNaB组),每组每重复随机选取6只体重相近的50日龄雌性肉鸡,共72只。按2×3因子试验设计,以免疫应激种类(生理盐水和LPS)和饲粮类型(0、500 mg/kg NaB和250 mg/kg CNaB)作为LPS应激试验的主效因子。每组4个重复,每重复3只鸡。于50 d将其置于已清洗消毒好的3层立体鸡笼中饲养,继续饲喂相应的饲粮,适应2 d后,各组1/2鸡只于53、56和59 d腹腔注射E.coli LPS注射液(0.5 mg/kg BW),剩余鸡只注射等量生理盐水。于每天08:00至09:00进行注射,饲养为期10 d,常规饲养管理。

1.3 样品采集与保存

于每次LPS或生理盐水注射后4 h,每组随机抽取4只鸡,每重复1只,翼静脉采血,装入促凝管和乙二胺四乙酸二钠(EDTA-2Na)抗凝管中,待有液体自然析出后,4 ℃、3 000 r/min离心10 min,分装后于-80 ℃保存待测。

于60 d清晨从每组随机抽取4只鸡,每重复1只,进行屠宰,取肝脏,用滤纸吸干血渍后装入样品袋,锡箔纸包裹,置于液氮中保存待测。

1.4 测定指标与方法 1.4.1 血液常规生化指标测定

56 d注射后所采集的血清用于评估LPS连续应激过程中葡萄糖(Glu)、甘油三酯(TG)、尿酸(UA)含量和黄嘌呤氧化酶(XOD)活性的变化,相关测定均按照南京建成生物工程研究所的试剂盒说明进行。

1.4.2 抗氧化指标测定

取一小块肝脏组织,用预冷的生理盐水漂洗血渍、滤纸拭干,称取0.5 g,加生理盐水4.5 mL,于冰浴中充分匀浆,制成10%组织匀浆,4 ℃、3 000 r/min离心10 min,取上清液于-20 ℃保存待测。

冻存的待测血清和上述10%肝脏匀浆上清液用于超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GSH-Px)活性和丙二醛(MDA)含量测定,相关测定采用南京建成生物工程研究所试剂盒进行。

1.4.3 血清应激相关因子测定

血清中促炎细胞因子白细胞介素-6(IL-6)含量采用鸡酶联免疫吸附测定法(ELISA)试剂盒测定,血清中急性应激蛋白铜蓝蛋白(CP)含量采用南京建成生物工程研究所试剂盒测定。

1.5 数据处理

所得数据采用SPSS 16.0软件中GLM过程Univariate进行方差分析,采用最小显著差异法(least significant difference,LSD),P<0.05表示差异显著。其中全模型包括饲粮和免疫应激2个固定效应及二者互作效应,数据均以平均值和SEM表示。

2 结 果 2.1 丁酸钠对肉鸡生长性能的影响

由表2可知,1~21日龄,与对照组相比,饲粮中添加250和500 mg/kg CNaB显著提高了肉鸡平均日增重(P<0.05),并显著降低了料重比(P<0.05),添加750 mg/kg CNaB显著提高了平均日采食量和平均日增重(P<0.05),各CNaB组间平均日增重差异不显著(P>0.05)。各期添加500 mg/kg NaB的肉鸡生长性能指标均与对照组差异不显著(P>0.05)。22~50日龄和1~50日龄,各组间肉鸡生长性能指标均无显著差异(P>0.05)。在本试验条件下,生长性能总体比较,250 mg/kg CNaB组生长性能最优。

表2 丁酸钠对肉鸡生长性能的影响 Table 2 Effects of sodium butyrate on growth performance of broilers
2.2 应激试验结果 2.2.1 丁酸钠对LPS应激肉鸡血清生化指标的影响

由表3可知,与生理盐水注射组相比,LPS注射组显著降低了血清中Glu和TG含量(P<0.05),显著提高了血清UA含量(P<0.05)。LPS注射下,NaB组和CNaB组中血清Glu含量均显著高于对照组(P<0.05)。LPS注射和饲粮中添加丁酸钠对肉鸡血清生化指标均不存在交互作用(P>0.05)。

表3 丁酸钠对LPS应激肉鸡血清生化指标的影响 Table 3 Effects of sodium butyrate on serum biochemical indices of broilers challenged with LPS
2.2.2 丁酸钠对LPS应激肉鸡抗氧化功能的影响

由表4可知,与生理盐水注射组相比,LPS注射组极显著降低了血清SOD活性(P<0.01),显著降低了血清GSH-Px和CAT活性(P<0.05)。LPS注射下,NaB组和CNaB组血清SOD、GSH-Px、CAT活性均高于对照组(P>0.05)。LPS注射和饲粮添加丁酸钠对肉鸡血清抗氧化功能均不存在交互作用(P>0.05)。

表4 丁酸钠对LPS应激肉鸡血清抗氧化功能的影响 Table 4 Effects of sodium butyrate on serum antioxidant function of broilers challenged with LPS

由表5可知,与生理盐水注射组相比,LPS注射组极显著降低了肝脏中SOD和GSH-Px活性(P<0.01),CAT活性和MDA含量无显著差异(P>0.05)。LPS注射下,NaB组和CNaB组肝脏中SOD、CAT活性略高于对照组(P>0.05),MDA含量低于对照组(P>0.05)。LPS注射和饲粮添加丁酸钠对肝脏GSH-Px活性存在交互作用(P<0.05),而对SOD、CAT活性和MDA含量不存在交互作用(P>0.05)。

表5 丁酸钠对LPS应激肉鸡肝脏抗氧化功能的影响 Table 5 Effects of sodium butyrate on liver antioxidant function of broilers challenged with LPS
2.2.3 丁酸钠对LPS应激肉鸡抗炎功能的影响

由表6可知,与生理盐水注射组相比,LPS注射组极显著提高了53和59 d血清CP和IL-6含量(P<0.01),56 d血清CP和IL-6含量均无显著差异(P>0.05)。LPS注射下,NaB组和CNaB组53 d血清CP含量显著低于对照组(P<0.05)。

表6 丁酸钠对LPS应激肉鸡抗炎功能的影响 Table 6 Effects of sodium butyrate on anti-inflammation function of broilers challenged with LPS
3 讨 论 3.1 丁酸钠对LPS应激肉鸡血清生化指标的影响

Glu、TG和UA是反映机体3大物质代谢的重要指标。本研究结果表明,LPS注射显著降低了血清Glu、TG含量,显著提高了血清UA含量,具有提高XOD活性的趋势,表明LPS应激抑制了机体的物质代谢,这和以往研究结果相类似[2, 6, 7, 8]。本研究结果表明,LPS注射下,NaB组和CNaB组血清Glu含量均显著高于对照组,且均具有提高Glu和TG含量的趋势,表明丁酸钠有能部分缓解Glu和TG含量降低的作用,从而改善机体应激下的物质代谢,这和Zhang等[2]结果相一致,其结果表明1.0 g/kg NaB显著抑制了由LPS注射引起的20 d肉鸡血清Glu含量的降低,且部分缓解16 d肉鸡血清TG含量的变化。由此推断饲用丁酸钠有助于改善应激条件下动物机体的营养代谢。

3.2 丁酸钠对LPS应激肉鸡抗氧化功能的影响

细菌内毒素LPS可用于模拟氧化应激和疾病状态的模型构建,LPS在引起急性反应的同时也能产生氧化损伤,且被证实能减少抗氧化物酶的表达,LPS能增加XOD活性,从而使过氧化物或超氧化物含量增加[9]。此外,有大量研究表明内毒素能降低SOD、CAT、GSH-Px活性,增加MDA含量[9, 10, 11]。本研究结果表明,LPS注射显著降低了血清SOD、GSH-Px和CAT活性,具有提高MDA含量的趋势。LPS注射显著降低了肝脏SOD、GSH-Px活性,却对CAT活性和MDA含量无显著影响,这与上述相关研究相一致[9, 10, 11]。LPS注射下,NaB组和CNaB组血清和肝脏抗氧化物酶活性均有所增强,MDA含量均有所下降,这表明2种剂型丁酸钠在一定程度上能缓解LPS诱导产生的氧化应激,增强应激条件下机体的抗氧化能力。肉鸡体脂含量较高易发生脂质过氧化反应,而丁酸钠在一定程度能增强应激下机体的抗氧化能力,这对预防和减少肉鸡脂质过氧化具有一定意义。

3.3 丁酸钠对LPS应激肉鸡抗炎功能的影响

CP是一种众所周知的家禽急性阶段反应特有的正相反应蛋白,其在血清中含量的升高被认为是一种炎症反应增强的指示物[12],其含量过高或长期存在会引起机体损伤[9]。大量研究表明,LPS注射能引起CP、α1-酸性糖蛋白(AGP)等含量的增加[2, 8, 9, 13]。LPS应激除了能引起机体急性期反应蛋白含量的增加外,也能使机体单核细胞和巨噬细胞合成和分泌的炎性细胞因子白细胞介素-1(IL-1)、IL-6和肿瘤坏死因子-α(TNF-α)含量的增加[14, 15, 16],其中IL-6是肝脏分泌的众多急性反应蛋白的最主要调节子,且具有内分泌和代谢调节作用[17],能增加室旁核中促肾上腺皮质激素释放激素的分泌,激活下丘脑-垂体-肾上腺皮质轴[18],导致糖皮质激素释放,进而通过糖皮质激素受体迅速降低血液中胸腺依赖性细胞、单核细胞及自然杀伤细胞(NK),数量一旦免疫细胞进入皮肤、淋巴结组织,细胞因子就会作为局部调节物介入如干扰素-γ(IFN-γ),调控随后的免疫功能。

本研究表明,LPS应激下53和59 d血清CP含量显著升高,这与相关研究结果[8, 9, 13, 18]相一致。LPS注射下,NaB组和CNaB组均能显著缓解LPS应激所引起的53 d血清CP含量的升高,且有降低59 d血清CP含量的趋势。LPS应激下53和59 d血清IL-6含量显著升高,这与以往研究结果[2, 7]相类似。已有研究证实,丁酸能抑制特别是LPS应激下细胞因子的释放[19],且丁酸钠也能降低肉鸡或猪血清IL-6含量[2, 20]。本研究中丁酸钠具有降低53 d血清IL-6含量的趋势,以上结果表明饲用丁酸钠在一定程度上缓解了LPS注射诱导的急性应激反应。此外,LPS注射对56 d血清CP和IL-6含量均无显著影响,可能是机体产生短暂的免疫耐受现象,但是这种短暂免疫耐受又会被多次LPS注射所打破[2],具体机制还有待进一步研究。

4 结 论

在应激条件下,饲用NaB和CNaB能改善肉鸡的营养代谢,维护机体抗氧化功能,增强抗炎功能,有效缓解应激诱导的不良反应,且500 mg/kg NaB和250 mg/kg CNaB(有效含量为75 mg/kg)作用效果基本一致。

参考文献
[1]ORCHEL A,GRUCHLIK A R,WEGLSRZ L,et al.Influence of sodium butyrate on antioxidative enzymes activity in Caco-2 cell lines[J]. Acta Poloniae Pharmaceutica,2006,63(5):441-442. (1)
[2]ZHANG W H,JIANG Y,ZHU Q F,et al.Sodium butyrate maintains growth performance by regulating the immune response in broiler chickens[J]. British Poultry Science,2011,52(3):292-301. (8)
[3]MACHADO R A,DE SOUZA CONSTANTINO L,TOMASI C D,et al.Sodium butyrate decreases the activation of NF-κB reducing inflammation and oxidative damage in the kidney of rats subjected to contrast-induced nephropathy[J]. Nephrology Dialysis Transplantation,2012,27(8):3136-3140. (1)
[4]赖衍宗.丁酸钠对TNBS结肠炎模型大鼠肠黏膜修复的影响[D]. 硕士学位论文.南京:南京大学,2011:17-18. (1)
[5]王纯刚,张克英,丁雪梅.丁酸钠对轮状病毒攻毒和未攻毒断奶仔猪生长性能和肠道发育的影响[J]. 动物营养学报,2009,21(5):711-718. (1)
[6]XIE H,RATH N C,HUFF G R,et al.Effects of Salmonella typhimurium lipopolysaccharide on broiler chickens[J]. Poultry Science,2000,79(1):33-40. (1)
[7]WEBER T E,KERR B J.Effect of sodium butyrate on growth performance and response to lipopolysaccharide in weanling pigs[J]. Journal of Animal Science,2008,86(2):442-450. (2)
[8]SONG Z G,ZHU L X,ZHAO T,et al.Effect of copper on plasma ceruloplasmin and antioxidant ability in broiler chickens challenged by lipopolysaccharide[J]. Asian-Australasian Journal of Animal Sciences,2009,22(10):1400-1406. (3)
[9]ZHANG H J,GUO Y M,TIAN Y D,et al.Dietary conjugated linoleic acid improves antioxidant capacity in broiler chicks[J]. British Poultry Science,2008,49(2):213-221. (6)
[10]GHOSH B,HANEVOLD C D,DOBASHI K,et al.Tissue differences in antioxidant enzyme gene expression in response to endotoxin[J]. Free Radical Biology and Medicine,1996,21(4):533-540. (2)
[11]ABD-ALLAH A R A,HELAL G K,AL-YAHYA A A,et al.Pro-inflammatory and oxidative stress pathways which compromise sperm motility and survival may be altered by L-carnitine[J]. Oxidative Medicine and Cellular Longevity,2009,2(2):73-81. (2)
[12]MATSUSHITA K,TAKAHASHI K,AKIBA Y.Effects of adequate or marginal excess of dietary methionine hydroxy analogue free acid on growth performance,edible meat yields and inflammatory response in female broiler chickens[J]. The Journal of Poultry Science,2007,44(3):265-272. (1)
[13]TAKAHASHI K,KAWAMATA K,AKIBA Y,et al.Influence of dietary conjugated linoleic acid isomers on early inflammatory responses in male broiler chickens[J]. British Poultry Science,2002,43(1):47-53. (2)
[14]SHEN Y B,PIAO X S,KIM S W,et al.The effects of berberine on the magnitude of the acute inflammatory response induced by Escherichia coli lipopolysaccharide in broiler chickens[J]. Poultry Science,2010,89(1):13-19. (1)
[15]TAKAHASHI K,TAKIMOTO T,SATO K,et al.Effect of dietary supplementation of astaxanthin from Phaffia rhodozyma on lipopolysaccharide-induced early inflammatory responses in male broiler chickens (Gallus gallus) fed a corn-enriched diet[J]. Animal Science Journal,2011,82(6):753-758. (1)
[16]ZHOU T X,JUNG J H,ZHANG Z F,et al.Effect of dietary β-glucan on growth performance,fecal microbial shedding and immunological responses after lipopolysaccharide challenge in weaned pigs[J]. Animal Feed Science and Technology,2013,179(1/2/3/4):85-92. (1)
[17]GRUYS E,TOUSSAINT M J M,NIEWOLD T A,et al.Review:acute phase reaction and acute phase proteins[J]. Journal of Zhejiang University Science B,2005,6(11):1045-1056. (1)
[18]CHIKANZA I C,GROSSMAN A B.Neuroendocrine immune responses to inflammation:the concept of the neuroendocrine immune loop[J]. Baillière's Clinical Rheumatology,1996,10(2):199-225. (2)
[19]BAERT K,DUCHATEAU L,DE BOEVER S,et al.Antipyretic effect of oral sodium salicylate after an intravenous E.coli LPS injection in broiler chickens[J]. British Poultry Science,2005,46(2):137-143. (1)
[20]NANCEY S,BIENVENU J,COFFIN B,et al.Butyrate strongly inhibits in vitro stimulated release of cytokines in blood[J]. Digestive Diseases and Sciences,2002,47(4):921-928. (1)