| The destination of this study was the age of21days' piglets. The main line of the study was theintestinal epithelial cellular oxidation-development of enzyme-secret of promotinginflammation/anti-inflammation factors-growth and impairment recovery-stress and regulation ofnutrition. From the four experiments done, we evaluate the impairment and oxidation of piglets'intestinal epithelial cell caused by early-weaning and its regulation of DMY.1The study of early weaning to piglets' intestinal epithelial impairment and oxidationExperiment1:Eighty healthy piglets aged21±1days with average body weight6.25±0.37kg wereselected and divided into two groups which were suckling and weaning groups with four replicates ineach group, and ten piglets in each replicate. Samples were collected on the day of1,3,5,7,10,14after weaning. One piglet was scarified in each replicate in each group at once. The intestine usedto isolated intestinal epithelial cell, liver and blood used to inspect the indexes of oxidation,impairment, cellular factor and enzyme were harvested.(1) The activity of XO rose acutely and the concentration of uric acid rose on the1-3days afterweaning while the activity of antioxidational enzymes (CAT,SOD,GSH-Px) reduced and the contentof MDA rose. The activity of AKP,Na＋-K＋-ATP reduced. The content of cytokine IL-1rose and IL-10reduced. The concentration of EGF/EGFR and transcription of its mRNA reduced significantly.Intestinal epithelial cell happened to baffle denaturation. Capillary vessel in intestinal villus happenedto hyper-tention and blood. On5-7days after weaning, the indexes reached the submit or lowest,thenbecome to recover. On10-14days after weaning, they recovered to normal. It was concluded thatintestinal epithelial cell happened to oxidation and the development of enzymes AKP and Na＋-K＋-ATPwas obstructed causing by the early weaning. The content of promoting inflammation factor rose andthe anti-inflammation factor reduced. The generation of EGF/EGFR reduced. Intestinal villus atrophiedand crypt proliferation in structure.(2) On1-3days after early-weaning the activity of hepatic XO and the content of uric acid rose,while the activity of antioxidational enzymes reduced. The concentration of the oxidational productMDA rose. The activity of Na＋-K＋-ATP and GS reduced acutely. On3-5days after early-weaning,those indexes rose the submit or lowest, then become to recover which recover to normal on7-10days.It could be referred that liver happened to oxidation, activity of Na＋-K＋-ATP and GS reduced caused bythe early-weaning. That activity of GS reduced may be one of the reasons that influence the energeticmetabolism of intestinal epithelial cell, regeneration and impairment.(3) On1-3days after early-weaning the activity of antioxidational enzyme in piglets' serumreduced and the concentration of oxidaional product MDA rose. The concentration of IL-1rose, IL-10and slgA reduced. On the3-5days after weaning, the activity of antioxidational enzyme and thecontent of MDA reached submit or lowest, then become to recover which recover to normal on7-10days. The content of IL-1,IL-10and slgA reached submit on the7d after weaning, and maintained high level on10-14days.(4) When compared the same indexes in intestinal epithelial cell, liver and serum, we canconcluded that range of intestinal epithelial cellular indexes was the biggest, which lasted the longest.It suggested that impairment caused by early-weaning to intestinal epithelial cell was bigger than thatin liver and mechanism.2The oxidation and impairment of intestinal epithelial cell caused by HX/XO in vitro andprotection of supplemented DMY.Experiment2: Normally cultured the IEC-6cell lines. Choose the cell stick the wall and growwell to establish the oxidational model of xanthine and xanthine oxidase (HX/XO) in vitro. Allopurinolwas the inhibitor of this model. The cells were divided into6treatments: group â… was control. Theother five groups were added into different concentration of HX/XO to their last concentration reached25/25,50/50,100/100,150/150,200/200μmol/L, which was cultured for24h. Then inspected theindexes in cells. Results indicated that the activity of CAT and SOD could be reduced and theconcentration of oxidational product MDA was increased with a concentration of50/50μmol/LHX/XO. The activities of AKP and DAO was reduced significantly also the content of EGF/EGFRand the transcription of mRNA. The cellular activity of IEC-6was reduced significantly. The changes ofother indexes were the same as those of intestinal epithelial cell causing by the stress of early weaning.Added inhibitor:allopurinol to this model could prohibit the impairment of intestinal cell. The resultsadvised that the impairement of intestinal cell is directly related with the oxidational stress.Experiment3: To observe the protection of DMY to oxidation and impairment of intestinal cell.There were6treatment, which group â… was control. â…¡ was oxidational group(50/50μmol/L), â…¢wasthe inhibitor group(50/50μmol/L+200μmol/L),the remained groups were oxidation and DMY groupwhich the concentration of DMY was50,75,100μmol/L. Inspect the activity of IEC-6and indexes ofits oxidation and impairment. The results indicated that the activities of cellular antioxidational enzymesCAT and SOD were improved in HX/XO oxidational model with a concentration of75-100μmol/LDMY supplemented. The content of oxidational product MDA reduced and the activity of cellular AKPimproved. The activity of DAO in cellular culturation reduced and the content of EGF/EGFR improvedas well as the mRNA transcription. The activity of cellular proliferation was promoted. Supplementedallopurinol with a dose of200μmol/L, there were no differences on the indexes with the control.That the system of HX/XO could produce oxidation and stress to cells which caused impairmentto intestinal epithelial cell was proved by the experiment2and3in two different ways3The study of supplemented DMY to early-weaning piglets on intestinal epithelial cell oxidation,impairment and recoveryExperiment4: Seventy-two healthy piglets aged21±1days with average body weight6.33±0.34kg were selected and divided into two groups which were weaning and DMY supplemented groupswith4replicates in each group, and9piglets in each replicate. Intestinal tissue used to isolatedintestinal epithelial cell, liver and blood were harvested from one piglet in one replicate in a group on0,1,3,7,14days after weaning. Body weight was recorded on the days of7,14and28and the consumption of feedstuff.(1) Dietary supplemented DMY at a dose of0.05%could reduce the activity of piglets' intestinalepithelial cellular XO and content of uric acid. Improved the activity of CAT and SOD. Reduced theconcentration of MDA. Improved the activity of AKP and Na＋-K＋-ATP. Reduced the content ofcytokine IL-1. Improved the content of IL-10and EGF/EGFR also their transcription of mRNA.Structure of intestinal villus and crypt were intact overall. It advised that dietary supplemented DMYcould reduce the impairment of early-weaning piglets' intestinal epithelial cell and promote theproliferation and differentiation of intestinal epithelial cell. Promote growth and development ofintestinal villus and crypt.(2) Dietary supplemented DMY with a dose of0.005%could reduce the activity of piglets'hepatic XO and the content of uric acid on the7days after weaning. Improved the activity of CATand SOD. Reduced the concentration of MDA, Improved the activity of Na＋-K＋-ATP while there wereno significant influences on activity of GS.(3) Dietary supplemented DMY with a dose of0.005%could improve the activity of piglets'serum CAT and SOD and the content of IL-10and slgA. Reduced the concentration of MDA and IL-1.(4) Dietary supplemented DMY with a dose of0.005%could improve the daily body weight andfeedstuff conversion rate.In summary of the above four experiments: the oxidation of intestinal epithelial cell was inducedby early-weaning from the way of XO which made the activity of antioxidational enzymes reduce andthe development of secreted enzymes prohibit. The concentration of IL-1improved. Concentration ofIL-10and sIgA reduced. Growth and recovery factors transcription and synthesis reduced which maycontribute to structure of intestinal villus and crypt impaired and recovery inhibited. Intestinal villusshowed atrophy and crypt became deep in structure. Dietary supplemented DMY to piglet couldprohibit the oxidation made by XO and reduce the impairment of intestinal epithelial cell caused byearly-weaning. Improved the function of recovery. Promoted the proliferation and differentiation ofintestinal epithelial cell and development of intestinal villus and crypt. Improved the growthperformance of piglet. |
