Effect And Mechanisma Of Oregano Essential Oil On Improve Rat Oxidative Stress

The intestinal mucosa is not only the largest interface between the outside world and the lumen itself, but also has selective penetration and absorption of nutrients and intestinal microbial defense and proinflammatory cytokines intrusion barrier function. Tight junction as an important part of intestinal mucosa barrier, play an important role in maintenance of integrity of intestinal mechanical barrier. However, in the modern animal production, many factors can induce oxidative stress. Recent studies had found that oxygen free radical is a common part of intestinal mucosal damage caused by many pathogenic factors. Oregano Essential Oils (OEO) has a antibacterial and antioxidant effect, mostly attributable to the presence of phenolic compounds. So OEO can be used as a dietary antioxidant to improve the harm of oxidative. First, we research and evaluate OEO antibacterial and antioxidant properties; Second, thought the IPEC-J2 cells oxidative stress model to study the protective effects and intervention mechanisma of OEO on IPEC-J2. Third, establish of rat model of oxidative stress by diquat, research the biochemical indicators of serum, barrier function and micro flora of intestinal, in order to reveal the way of OEO alleviate oxidative stress. The result as follows:1.Research of antioxidative and antimicrobial characteristics of OEO in vitro. Establishment of rat liver homogenate lipid autoxidation model to campare the inhibition lipid autoxidation rate of VE、 VC、OEO. The value of IC50 are 0.756 mg/ml、0.21 mg/ml、OEO 0.03 mg/ml respectively. The order of this three antioxidative is OEO>VE >VC. Study of OEO regulate chimy redox status in vitro, the content of ROS in the fermentation fluid were gradually increased and reached a maximum in 8h. The content of ROS in OEO groups were gradually decreased campared with the control groups. Study of antimicrobial effect of OEO, the result show that OEO can significantly inhibited the growth of Escherichia coli and Enterococcus faecalis, the inhibitory effect of OEO occurred mainly in the logarithmic phase and has a dose-effect.2.Protective effects and intervention mechanisma of OEO on IPEC-J2 following oxidative stress. Different concentration of OEO and H2O2, incubated with IPEC-J2 for 24h and the cell vitality measured by MTT. Optimal concentration by OEO and H2O2 were OEO 2×10-3ul/ml and 0.8um. The protective effect of OEO on Tjs was analyzed by immunofluorescence microscopy. H2O2 markedly disrupted the Tjs network of IPEC-J2 and the normal distribution of ZO-1、Occludin and Factin. While OEO treatment markedly attenuated the Tj abnormalities induced by H2O2.3.Protective effects and intervention of OEO against oxidative stress induced by diquat in rat. Thirty male wistar rat,7 to 8 weeks old, were randomly divided into three groups. Control and stress groups fed a basal diet, OEO groups fed a diet added 300mg/kg OEO. After 21 days, all treatment groups, except control group, received 0.1 mmol/kg bw of diquat i.p. dissolved in normal saline. Control group received an equal dose of normal saline i.p. The rat were killed 6h after i.p. of diquat or saline, then the samples were collected. The result showed as follows:1) Effect of OEO on rat growth performance: Compare with the control group, OEO groups improve average daily feed intake (ADFI) and average daily gain (ADG) (P<0.01).2) The assessment of the state of oxidative stress and intervention effect of OEO:NE levels in serum increased in stress groups and OEO groups compare with control groups, but no significant effect in stress groups and OEO groups; Jejunal mucosa HSP70 mRNA expression was increased in stress groups and OEO groups.3) Antioxidative capability in rat under oxidative stress and intervention effect of OEO:The activitive of SOD in serum were no significant effect in three groups (P>0.05); the activitive of GSH-Px in serum were significant decreased in stress groups and OEO groups (P<0.01); the content of MDA were significant increased in stress groups (P<0.01).4) The protective effect of OEO on intestinal epithelial barrier function: The content of D-xylose in serum were significant increased in stress groups (P<0.01) but no significant in control and OEO groups (P>0.05); villus height were significant decreased in stress groups and OEO groups (P<0.01); villous width were significant increased in stress groups (P<0.01); crypt depth were significant increased in stress groups (P<0.01),the ratio of villous height and crypt were significant different in this three groups; Occludin mRNA expression were sinnificant decreased in stress groups, Occludin mRNA expression were higher in OEO groups than stress groups (.P<0.05); ZO-imRNA expression were significant decreased in stress groups and OEO groups (P< 0.01).5) Effect of OEO on oxidative stress in rat intestinal flora structure:DGGE profiles similarity analysis revealed that the addition of OEO in diets can improve the OEO groups similarity, but the diversity index and bands were no significant effect.In sumary, the conclusions of the present study are:(1) Study of OEO regulate chimy redox status using fermentation model in vitro, the result showed that OEO could reduce the content of ROS thought inhibit the proliferation of bacteria producing free radicals. (2) OEO has a protective effects with tight junction when cell in oxidative.(3) OEO not only had helpful for the growth performance of the rat, but also protected the rat with intestinal barrier function, by inhibitioning the mucosa atrophy, improving the micro-enviroment of gut, increasing intestinal tight junction expression and reducing intestinal permeability.