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1.
维生素D的应用形式有维生素D2、D3、25-OHD3和1,25-(OH)2-D3几种形式,其中D3为最常用的形式。25-OH-D3是维生素D 3在肝脏中转化后的一种形式,随后又在肾脏中转化为最终活性形式1,25-(OH)2-D3。作为维生素D3和1,25-(OH)2-D 3的中间产物,25-OH-D3在动物体内活性比维生素D3更高,吸收更有效。1维生素D的生理功能及其在动物体内的代谢维生素D通过类似于类固醇激素的作用机理对动物的许多生物学功能进行调节,主要在以下几个方面发挥作用:1)维持动物体内钙、磷稳恒,保持骨骼的正常生长发育,防止钙缺乏症,如软骨病、佝偻病等,这是维生素D最重要的生理功能。2)提高肉品质。维生素D可刺激机体骨钙的动员,并且促进扩流入骨骼肌细胞中,使钙激酶被激活,从而促进肉的嫩化。  相似文献   

2.
为了探究猪细小病毒(porcine parvovirus, PPV)非结构蛋白NS1介导炎症反应的情况,将PPV NS1重组质粒转染至PK-15细胞,应用实时荧光定量PCR和免疫印迹技术分别检测炎性因子IL-6/TNF-α的表达和NF-κB信号通路相关蛋白的激活。结果显示,PPV NS1极显著诱导IL-6和TNF-αmRNA的表达(P<0.01)。PPV NS1可显著促进IκBα的降解、p65的磷酸化来激活NF-κB信号通路(0.01相似文献   

3.
饮水添加25-OH-D3对肉仔鸡胫骨质量的影响   总被引:1,自引:0,他引:1  
梁彦明  王浩 《广东饲料》2009,18(1):23-26
维生素D是促进动物机体钙磷吸收的主要因素,对动物骨骼生长有重要意义;而动物从日粮中摄取的维生素D必须转化为25-OH-D3、1,25-(OH)2-D3、25,26-(OH)2-D3等代谢物后才具有生物活性,并有效地发挥其生理生化功能。  相似文献   

4.
25-OH-D3及1,25-(OH)2-D3是维生素D的真正活性形式,本文对25-OH-D3及1,25-(OH)2-D3的生物学功能、吸收代谢特点和影响因素进行了综述,为为其应用提供理论参考。  相似文献   

5.
体外培养围产期奶牛外周血淋巴细胞,分别添加0、0.01、0.1、1、10和100nM的1,25(OH)_2D_3,研究1,25-(OH)_2D_3对奶牛外周血淋巴细胞免疫功能的影响。结果表明,1,25-(OH)_2D_3对淋巴细胞转化率没有影响,但可以通过抑制IFN-γ的分泌影响奶牛的细胞免疫功能。添加0.01~100nM的1,25-(OH)_2D_3对淋巴细胞的转化率没有显著影响,但剂量依赖性抑制了ConA和PWM诱导的淋巴细胞IFN-γ的产量。当1,25(OH)_2D_3浓度达到0.1nM、1nM时与对照组相比分别显著(P<0.05)和极显著(P<0.01)抑制ConA诱导的淋巴细胞IFN-γ的产量。以PWM激活的细胞在培养48h、72h,1,25-(OH)_2D_3添加量在0.1~100nM范围均极显著抑制IFN-γ的产生(P<0.01)。添加0.01nM 1,25(OH)_2D_3对IFN-γ的抑制作用相对较小(P>0.05),在培养48h后并未表现出显著的抑制作用,但培养72h后也极显著的抑制了IFN-γ的产生(P<0.01)。  相似文献   

6.
试验旨在研究不同水平1,25-二羟基维生素D3(1,25-(OH)2-D3)对1~14日龄肉鸡生长性能、骨骼矿化及促进十二指肠磷吸收关键基因表达的影响。将180只1日龄罗斯308肉鸡分入3个处理,每处理6个重复,每重复10只。3个处理组分别饲喂3种日粮:在基础日粮中分别添加0、5、10μg/kg 1,25-(OH)2-D3,试验期14d。14日龄屠宰肉鸡,剥离股骨、胫骨及十二指肠1/2处的黏膜;测定肉鸡的生长性能、骨骼矿化相关指标,分析Ⅱb型磷酸钠转运蛋白(NaPi-Ⅱb)、细胞核维生素D受体(nVDR)和细胞膜维生素D受体(mVDR)基因表达情况。结果显示:与基础日粮组相比,添加5μg/kg 1,25-(OH)2-D3组肉鸡体增重、采食量、料重比、股骨和胫骨各指标(重量、长度、直径、灰分重量、灰分含量、钙、磷含量)及十二指肠NaPi-Ⅱb、nVDR和mVDR mRNA表达量均未发生显著变化(P0.05);添加10μg/kg 1,25-(OH)2-D3显著降低了肉鸡体增重、采食量、股骨和胫骨各指标及十二指肠NaPi-Ⅱb、nVDR和mVDR mRNA表达量(P0.05),同时料重比显著增加(P0.05)。综合上述结果,在基础日粮中添加5μg/kg 1,25-(OH)2-D3不会影响1~14日龄肉鸡的生长、骨骼矿化及十二指肠磷吸收关键基因表达;但添加量增至10μg/kg会显著抑制1~14日龄肉鸡生长、骨骼发育,影响十二指肠NaPi-Ⅱb和VDR mRNA表达。  相似文献   

7.
为证实Toll样受体2(TLR2)是否参与2型猪链球菌诱导的细胞自噬作用,通过阻断TLR2,并建立2型猪链球菌感染J774A.1细胞模型,分别应用荧光定量PCR分析不同处理组细胞TLR2和NF-κB mRNA水平、ELISA检测细胞上清中TNF α和IL-6含量变化以及Western blot检测细胞内LC3蛋白的表达量.结果显示,TLR2和NF-κBmRNA水平在感染后3h明显高于对照组;与对照组相比,感染组TNF-α含量及LC3Ⅱ表达均明显升高(P<0.01);与感染组相比,阻断TLR2后TNF-α含量及LC3Ⅱ表达均明显降低(P<0.05).结果表明,2型猪链球菌可激活TLR2及其信号通路,并且该通路的活性影响细胞自噬作用.  相似文献   

8.
本试验旨在探索乳酸杆菌诱导绵羊瘤胃上皮细胞SBD-1表达的可能途径。采用实时荧光定量PCR(RTqPCR)的方法,对已建立的诱导SBD-1表达模型中Toll样受体2(Toll like receptor 2,TLR2)及其相关因子的基因表达变化进行检测;然后选用3种信号通路抑制剂,即NF-κB信号通路抑制剂PDTC、ERK 1/2信号通路抑制剂PD98059和JNK信号通路抑制剂SP600125,将细胞分为8组:细胞组:不作处理;阳性对照组:只添加植物乳杆菌P-8(L.plantarum P-8)诱导;PDTC组:只添加PDTC预处理细胞(PDTC);PDTC+L.plantarum P-8组:PDTC+L.plantarum P-8诱导;PD98059组:PD98059;SP600125组:SP600125;PD98059+L.plantarum P-8组:PD98059+L.plantarum P-8;SP600125+L.plantarum P-8组:SP600125+L.plantarum P-8。采用RT-qPCR的方法检测各组SBD-1mRNA表达水平。结果表明,绵羊瘤胃上皮细胞被L.plantarum P-8诱导后,TLR2及其转接蛋白MyD88、NF-κB和ERK1/2、JNK各基因的mRNA水平都较空白组细胞内的表达极显著增加(P0.01);添加抑制剂后再诱导,发现抑制剂PD98059和SP600125均能极显著(P0.01)抑制细胞内SBD-1 mRNA的表达,而PDTC仅能显著抑制(P0.05)SBD-1的表达。结果表明,L.plantarum P-8可促进绵羊瘤胃上皮细胞TLR2、MyD88、NF-κB、JNK和ERK1/2基因的mRNA表达;添加NF-κB信号通路抑制剂PDTC、ERK 1/2信号通路抑制剂PD98059和JNK信号通路抑制剂SP600125,可抑制L.plantarum P-8对SBD-1mRNA的诱导作用。综上表明,L.plantarum P-8有可能通过激活绵羊瘤胃上皮细胞内NF-κB、JNK、ERK1/2等信号通路促进SBD-1的表达。  相似文献   

9.
目的 探讨1,25-(OH)2D3及TLR4配体(脂多糖,LPS)对2型糖尿病(T2DM)和糖尿病肾病(diabetic nephropathy,DN)尿毒症患者血清干预的单核细胞维生素D受体(VDR)表达的影响,进一步探索1,25-( OH)2D3在T2DM和DN炎症性免疫反应中的作用.方法 分离研究对象(健康对照组、T2DM组和DN尿毒症组)外周血血清,孵育THP-1单核细胞,然后于含或不含10-7 mol/L的1,25-(OH)2D3培养液中培养48 h后,再用终浓度为1μg/ml的LPS干预24h,收集单核细胞和培养上清.采用RT-PCR检测VDR mRNA表达,Western blot、免疫荧光检测THP-1单核细胞内VDR蛋白表达.ELISA法检测细胞培养上清IL-6和IL-10浓度.结果 与正常对照组比较,在LPS的刺激下T2DM组和DN尿毒症组THP-1单核细胞内VDR mRNA水平下调[对照组(0.99±0.25);T2DM组(0.65±0.24);DN尿毒症组(0.62±0.27),P<0.05];DN尿毒症组THP-1单核细胞内VDR蛋白表达比正常对照组和T2DM组显著下调[对照组(0.48 ±0.05);T2DM组(0.50±0.06);DN尿毒症组(0.20±0.01),P<0.01],且LPS增强以上患者血清孵育的THP-1单核细胞炎症细胞因子IL-6的分泌[对照组(15.13±1.61);T2DM组(24.06 ±2.92);DN尿毒症组(70.77 ±5.48),P<0.05];而1,25-(OH)2D3可部分阻断上述作用.结论 LPS能下调T2DM和DN尿毒症患者单核细胞VDR mRNA和蛋白的表达,引起促炎和抗炎细胞因子失调.1,25-(OH)2D3可部分逆转LPS的作用,对T2DM和DN尿毒症可能具有一定的保护作用.  相似文献   

10.
贺兵 《吉林畜牧兽医》2014,35(12):17-18
<正>维生素D通过调节钙、磷吸收维持动物机体正常功能。养殖生产中,通常采用维生素D3来满足畜禽维生素D的需要。维生素D3吸收入机体后,首先在肝脏中转化成25-羟基钙化醇(25-OH-D3)然后到达肾脏被羟化成激素形式的代谢物1,25-(OH)2-D3实现维生素D的生物学功能。研究认为Hy.D(25-OH-D3)不受肠道胆酸分泌和脂肪的影响,比维生素D3更易吸收;而且可避免维  相似文献   

11.
1,25-Dihydroxycholecalciferol (1,25-(OH)2-D3) and 25-hydroxycholecalciferol (25-OH-D3) were measured among dogs with hypercalcaemia (total serum calcium > 3.01 mmol/L) due to various causes. All values were compared to those of healthy control dogs. Serum 1,25-(OH)]2-D3 was measured by a radioimmunoassay test and serum 25-OH-D3 was measured by a protein binding assay. 1,25-(OH)2-D3 ranged from 26 to 332 pmol/L (median 110.0) in dogs with lymphoma (n = 12); from 61 to 398 pmol/L (median 248.0) in dogs with primary hyperparathyreoidism (n = 5); from 28 to 310 pmol/L (median 88.5) in dogs with chronic renal failure (n = 10); and from 60 to 239 pmol/L (median 157.5) in control dogs (n = 24). There was no significant difference in 1,25-(OH)2-D3 among dogs with different causes of hypercalcaemia. 25-OH-D3 ranged from 64 to 291 nmol/L (median 101.5) in dogs with lymphoma; from 66 to 298 nmol/L (median 91.0) in dogs with primary hyperparathyreoidism; from 35 to 184 nmol/L (median 67.0) in dogs with chronic renal failure; and from 48 to 350 nmol/L (median 306.5) in control dogs. 25-OH-D3 was significantly lower in dogs with lymphoma, primary hyperparathyroidism and chronic renal failure than in control dogs. 1,25-(OH)2-D3 and 25-OH-D3 are not predictable in dogs with hypercalcaemia.  相似文献   

12.
Toll‐like receptor 2 (TLR2) is a receptor for a variety of microbial components, and it also mediates activation signals in the cell relating to the innate immune system. In order to evaluate the precise molecular immunoregulation by various strains of lactic acid bacteria (LAB) via TLR2, the swine TLR2 (sTLR2)‐expressing transfectant was constructed using human embryonic kidney (HEK) 293 cells. It is demonstrated that intact immunobiotic LAB can induce immune responses through TLR2, and that different nuclear factor‐κB (NF‐κB) activities of various strains can be accurately detected by sTLR2‐expressing HEK293 cells. Furthermore, cellular activation of NF‐κB via TLR2 is reflected in enhanced binding and uptake of LAB. The sTLR2‐expressing HEK293 cells were also useful for characterizing the expression pattern of type I helper T (Th1) and type II helper T (Th2) cytokines by the stimulation of immunobiotic LAB. These results suggest that sTLR2‐expressing HEK293 cells may be useful in certain molecular immunoassay systems for producing new physiologically functional foods with intestinal immunomodulatory abilities, such as the maintenance of Th1/Th2 polarization.  相似文献   

13.
14.
1,25(OH)2D3是维生素D的主要活性形式,影响人和动物脂肪形成,为探究其在猪脂肪细胞增殖分化中的作用,试验从3~5日龄仔猪皮下脂肪组织分离培养前体脂肪细胞,并以浓度为0、0.1、1、10、100和1 000 nmol/L的1,25(OH)2D3分别处理,在培养的0、1、2、4、6、8和10 d采用MTT比色法检测细胞增殖活性;在诱导分化后0、1、2、4、6、8和10 d,以油红O染色提取法和实时荧光定量PCR检测细胞成脂分化及分化标志基因过氧化物酶体增殖物激活受体γ(PPARγ)和脂肪酸合成酶(FAS)表达。结果显示,0.1和1 nmol/L 1,25(OH)2D3显著促进猪前体脂肪细胞增殖(P<0.05),而浓度为10~100 nmol/L时则抑制细胞增殖(P<0.05);0.1和1 nmol/L 1,25(OH)2D3显著抑制猪前体脂肪细胞分化(P<0.05),降低PPARγ和FAS mRNA表达水平(P<0.05),但在浓度为10和100 nmol/L时,显著促进猪前体脂肪细胞分化(P<0.05),上调PPARγ和FAS mRNA表达(P<0.05);浓度达1 000 nmol/L时,可能对细胞有毒性作用。综合以上结果,低浓度1,25(OH)2D3促进猪前体脂肪细胞增殖,而通过下调PPARγ表达抑制分化;高浓度1,25(OH)2D3抑制猪前体脂肪细胞增殖,通过上调PPARγ表达促进分化。1,25(OH)2D3对猪前体脂肪细胞增殖和分化具有双向作用。  相似文献   

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17.
Fifteen multiparous sows (three groups of five) were studied during one gestation-lactation cycle to measure the influence of dietary Ca (.5, .8[control], and 1.1%) on 1,25-dihydroxycholecalciferol (1, 25-(OH)2D3) in serum and colostrum of the sows and serum of their pigs. Concentrations of 1,25-(OH)2D3 and Ca, Mg, P, Cu, and Zn were determined on d 15 and 45 of gestation, at parturition, and at 3 wk postpartum in sow serum and at birth and d 10 and 21 in pig serum. Colostrum was assayed for 1,25-(OH)2D3. Serum 1,25-(OH)2D3 in sows was affected inversely (P less than .05) by dietary Ca within d 15 of gestation and was correlated (r = -.88) with serum Ca during gestation and lactation. Serum Ca was correlated (r = .52) with dietary Ca at d 15 and 45 of gestation and at farrowing. Sow serum Mg was inversely related (r = -.49) to serum Ca during gestation and early lactation. Serum 1,25-(OH)2D3 of the pigs at birth ranged from 38.7 to 44.2 pg/ml was decreased (P less than .05) by 1.1% maternal Ca intake. Sow colostrum 1,25-(OH)2D3 was related (P less than .05) inversely (r = -.40) to sow dietary Ca and directly (r = .90) to sow serum 1,25-(OH)2D3. Serum 1,25-(OH)2D3 of 10- and 21-d-old pigs was inversely related (P less than .05) to their dams' dietary Ca. These results indicate that 1,25-(OH)2D3 production in sows is quickly affected by modest changes in dietary Ca.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

18.
The plasma concentrations of 1,25-dihydroxycholecalciferol (1,25-(OH)2D3) (vitamin D3) were measured in blood samples taken from one wild rabbit and 13 pet rabbits at different times of the year. Some pet rabbits had low or undetectable plasma concentrations of 1,25-(OH)2D3 especially if they were kept in hutches. Rabbits with more access to sunlight had higher concentrations of 1,25-(OH)2D3.  相似文献   

19.
The purpose of this study was to examine iNOS gene expression and activity in macrophages from different chicken genetic lines against various bacterial LPS. Furthermore, the possible involvement of surface LPS receptors as candidates for differential iNOS gene induction in these genetic lines of chicken was also examined. Sephadex-elicited abdominal macrophages (1 x 10(6)) as well as iNOS hyper-responder macrophages from a transformed chicken macrophage cell line, MQ-NCSU, were exposed to 5 microg/ml LPS from E. coli, Shigella flexneri, Serratia marcensces, and Salmonella typhimurium. Nitrite levels were quantitated in the culture supernatant fractions of macrophages after 24h by the Griess method. The results showed that macrophages from K-strain (B(15)B(15)) (range from two separate trials: 31-89 microM) and MQ-NCSU (22-81 microM) were high responders whereas macrophages from both GB1 (B(13)B(13)) (15-38 microM) and GB2 (B(6)B(6)) (7-15 microM) chickens were low responders against all LPSs used. Northern blot analysis revealed that K-strain macrophages expressed higher intensity of 4.5Kb iNOS mRNA (iNOS/beta-actin ratio) than macrophages from GB2 regardless of the LPS source. To elucidate possible molecular mechanism(s) involved in iNOS gene expression in these two strains of chickens, the constitutive expression of LPS-related macrophage cell surface receptors, CD14, Toll-like receptor-2 (TLR2), and Toll-like receptor-4 (TLR4), was examined via flow cytometry using anti-human CD14, TLR2 and TLR4 antibodies. CD14 surface expression and intensity was not different between macrophages from K-strain or GB2 chickens. In contrast, while the overall percentage of TLR4-positive macrophages was the same (K-strain, trial 1=92%, trial 2=62%; GB2, trial 1=91%, trial 2=64%), the mean fluorescence intensity (MFI), an indicator of receptor number, was significantly higher (P=0.05) in K-strain macrophages (MFI: trial 1=145; trial 2=131) than GB2 macrophages (MFI: trial 1=101; trial 2=98). Furthermore, TLR2 (a previously thought candidate as LPS signaling molecule) positive cell numbers were higher in K-strain than the GB2 macrophages in one of the two trials with no difference in the intensity of TLR2 expression in either trial. These findings suggest that the observed differences in iNOS expression and activity among the K-strain (hyper-responder) and GB2 (hypo-responder) chickens are, at least in part, due to differential expression of TLR4 (an LPS signaling molecule), leading to more intense LPS-mediated activation of K-macrophages.  相似文献   

20.
Effects of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3), recombinant human transforming growth factor (rhTGF)-beta 1 and recombinant human bone morphogenetic protein (rhBMP)-2 on differentiation in four different canine osteosarcoma cell lines (POS53B, 53C, 53D and 14A) were examined using markers specifically expressed by phenotypic osteoblasts. 1,25(OH)2D3 increased alkaline phosphatase (ALP) activity in one cell line, osteocalcin production in two lines and type I collagen production in three lines. RhTGF-beta 1 increased ALP activity in one clonal cell, osteocalcin production in one clonal cell and type I collagen production in two clonal cells. RhBMP-2 increased ALP activity in all clonal cells, osteocalcin production in two clonal cells and type I collagen production in three clonal cells. Thus, these agents induced differentiation in osteosarcoma cells at different efficacies. Electron microscopic study revealed that these agents increased cellular activity in all cell lines with no evidence of degeneration of cell organelle by drug cytotoxicity. In some cultures treated with either 1,25(OH)2D3 or rhBMP-2, apoptotic cells were observed. Based on the change in markers, rhBMP-2 and 1,25(OH)2D3 seemed to be more effective than rhTGF-beta 1. These agents are potential inducers of apoptosis.  相似文献   

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