Effects Of Selenium-enriched Probiotics On Lipid Metabolism,Antioxidative Status,Histopathological Lesions And Biochemical Indices In Mice Fed By High Fat Diet

The global prevalence of obesity and related comorbidities has increased considerably over the past decades.In addition to an increase in food consumption and a reduction in physical activity,growing evidence implicates the microorganisms in our gastrointestinal tract,referred to as the gut microbiota,in obesity and related metabolic.The trace mineral selenium(Se)is an essential element for human and animal nutrition.The addition of Se to the diet through dietary supplements or fortified food/feed is increasingly common owing to the often sub-optimal content of standard diets of many countries.Se supplements commercially available include the inorganic mineral salts such as sodium selenite or selenate,and organic forms such as Se-enriched yeast.Aim of studyThe study was to evaluate the effect of selenium-enriched probiotics(SP)on lipid metabolism,antioxidant status,histopathology lesions and biochemical indices in mice fed High Fat Diet(HFD).Research design A total of 80 ICR female albino mice at four weeks age and 23 g of average weight were randomly allotted into five groups(n=16).The mice in group 1 as negative control fed a normal basal diet contained 0.05 ?g/g of Se.The mice in group 2 fed 15%HFD as positive control.The mice in group 3 were fed HFD+P(contained L.acidophilus 1011/mL and S.cerevisiae 109/mL CFU);mice in groups 4 and 5 fed HFD+SS and HFD+ SP were(sodium selenite and selenium-enriched contained 0.3 ?g/g of Se diet).The basal diets were formulated to meet the recommendations for mice of the National Research Council(NRC,1995)content 0.05 mg/kg of selenium.The animals were raced according to the laboratory establishment of Animal Experiment and Nanjing Agricultural University Animal Care Committee approved by Jiangsu Science and Technology Department[approval ID:Syxk(Jiangsu)2011-0036],housed in a room temperature at 25 ± 2 ? according to the experimental conditions,providing 12 hours dark/12 hours light.The SP and P products used in this study contain two probiotics strains of L.acidophilus 1011/mL colony-forming units(CFU)and yeast S.cerevisiae 109/mL(CFU)respectively.The total content of Se in the SP is 10.0 mg/L,with>90%being organic Se,and>75%being selenomethionine,which were detected by AF-610A atomic fluorescence spectrometer.The amount of probiotics contained in group C and E was same(L.acidophilus 0.25×1011/mL and S.cerevisiae 0.25 × 109/mL CFU).The SP and SS were mixed by ground High Fat Diet into powder.Levels of Total Protein(TP),Total cholesterol(TC),alanine aminotransferase(AST),and aspartate aminotransferase(ALT),were measured.The LDL,HDL and TG kits were provided by Nanjing Jiancheng Bioengineering Institute(Jiangsu,China).The GSH-Px,SOD,CAT enzymes activities and MDA level were measured.To determine the mechanisms underlying the SP effects on lipid homeostasis,we analyzed the mRNA levels of genes associated with lipid metabolism(CPT1,CPT2,ACOX2,ACAT2,FAS,LPL,PPAR?,PPAR? and SREBP2).The mice primer sequences shown in Table 1 were designed by Primer 5.0 online software.Results At the end of the experiment(5 weeks)blood and liver samples were collected for measurements of lipid metabolism,antioxidative status,histopathological lesions and related genes expression.The HFD Group showed increased body weight compared with the(A,C,D and E)Groups.Histopathological examination of liver showed less damage and hepatocytes arranged by penetrated fat vacuoles in Groups C,D and E compared to Group B.Serum AST,ALT,TC,TG,and LDL-C in Groups C,D and E significantly declined and TP and HDL-C increased compared to Groups B.SOD,CAT and GSH-Px enzyme activities significantly increased and MDA declined in Groups C,D and E compared to Groups B.Groups C,D and E showed moderate accumulation presence of lipid into hetapocytes compared do Group B.Generally,adding P,SS or SP up-regulated mRNA expression of CPT1,CPT2,ACAT2 ACOX2 and PPAR? and down-regulated mRNA expression of FAS,LPL,PPAR? and SREBP1 involved in lipid metabolism.Among the groups,adding SP has maximum effect in improving lipid metabolism,antioxidative status,histopathological lesions and related genes expression in mice fed by high fat diet.ConclusionHigh fat diet significantly promotes obesity,oxidative stress and altering lipid profile.The probiotic,selenium-enriched probiotics and sodium selenite used in our experiment could improve lipid profile,redox state and gene expression in mice induced obesity by fed high fat diet.