Effects Of Periplaneta Americana Extract On Oxidative Stress And NRF2/HO-1 Pathway In DSS-induced UC Mice

Objective: To explore the mechanism of therapeutic UC of Periplaneta americana extract and the active ingredients of Periplaneta americana extract against oxidative stress,and to provide a basis for further development of Periplaneta americana extract.Methods:(1)The quality of Periplaneta americana extract was analyzed by LCMS/MS.(2)The efficacy experiments were performed by pre-administration followed by modeling,with mesalazine as the positive control group and Periplaneta americana extract as each dose group,administered by gavage for 21 day.The mice were given2.5% DSS ad libitum for 14 day from 8 day and executed on 22 day.The efficacy of Periplaneta americana extract on UC was evaluated by measuring DAI score,colonic length,and HS score.The anti-inflammatory effect of Periplaneta americana extract on UC mice was evaluated by detecting the expression of serum IL-6,IL-10,TNF-αand IL-17 by ELISA.The effects of Periplaneta americana extract on oxidative stress in UC mice and its mechanism were evaluated by detecting total NRF2,nuclear NRF2 and cytoplasmic NRF2;total GCLM,NQO1,HO-1 and GPX2 expression by WB.The anti-oxidative stress effect of Periplaneta americana extract and amino acid mixture on NCM460 cells and its mechanism were measured by expression of ROS,SOD,MDA,GSH,GCLM,NQO1,HO-1 and GPX2 in human TNF-α stimulation induces oxidative stress model in NCM460 cells.Results:(1)The contents of alanine,glycine,tryptophan,threonine,tyrosine,valine,proline,phenylalanine,leucine and isoleucine in Periplaneta americana extract were 15.7 mg/g,11 mg/g,0.779 mg/g,3.03 mg/g,3.38 mg/g,6.03 mg/g,8.09 mg/g,2.99 mg/g,7.57 mg/g and 3.64 mg/g.(2)Periplaneta americana extract effectively alleviated the symptoms of shortened colon and weight loss in UC mice,significantly reduced DAI,and HS scores,down-regulated serum expression levels of IL-6,TNF-αand IL-17,and increased IL-10 expression(P<0.05 or P<0.01),and regulated downstream anti-oxidative stress proteins GCLM,NQO1,HO-1 and GPX2 expression by promoting NRF2 nuclear translocation.(3)Periplaneta americana extract can alleviate TNF-α-induced oxidative stress,of which proline and glycine have certain in vitro activities,and proline and glycine can be used as candidates for the quality control identification index of the effective active site of Periplaneta americana extract.Conclusion: Periplaneta americana extract can treat DSS-induced UC in mice through its anti-oxidative stress effect,and its anti-oxidative stress mechanism is related to the promotion of NRF2 nuclear translocation and the expression of downstreamrelated anti-oxidative stress proteins.Among them,glycine and proline can be used as candidates for the quality control identification index of the effective active site of Periplaneta americana extract.