Role and mechanism of sinomenine and sulfasalazine in experimental colitis of mice model / 中华消化杂志

ABSTRACT

Objective To investigate the role and mechanism of sinomenine and sulfasalazine (SASP) in experimental colitis of mice.Methods Seventy SPF grade Kunming mice were evenly divided into seven groups.Except control group,all mice were treated with oxazolone to create experimental colitis model.After modeling,the model group,low dose sinomenine group,high dose sinomenine group,low dose sinomenine combined group,high dose sinomenine combined group and SASP group was gavaged once daily with 0.9％ NaC1 solution 1 mL,40 mg/kg sinomenine,120 mg/kg sinomenine,40 mg/kg sinomenine and 400 mg/kg SASP,120 mg/kg sinomenine and 400 mg/kg SASP and 400 mg/kg SASP alone for seven days.The mouse stool characters,changes in body weight and fecal occult blood were recorded and disease activity index (DAI) was scored.The next day after the end of the intervention,all mice were sacrificed and specimens of the colon were obtained aud injury was scored.The specimens of inflammation part and ulcer site of colon were taken for histological examination and injury scoring.The expression of mitogen-activated protein kinase kinase 5 (MKK5),extracellular signal-regulated kinase 5 (ERK5),mitogen-activated protein kinase kinase 7 (MKK7),Jun N-terminal kinase (JNK),nuclear factor κB (NF-κB) at mRNA level were detected by reverse transcription-polymerase chain reaction (RT-PCR).The t-test was performed for comparison between groups.Results The DAI of low dose sinomenine group,high dose sinomenine group,low dose sinomenine combined group,high dose sinomenine combined group and SASP group was 2.33±0.77,1.03±0.73,2.70±0.67,1.60±0.66 and 2.03±0.79,respectively,the score of injury was 5.50±1.43,4.00±1.49,6.80±1.75,4.80±1.32 and 5.40±1.58,respectively,all were lower than those of model group (3.40±0.66 and 11.40±1.71) and the differences were statistically significant (tDA1 =3.33,7.61,2.34,6.08 and 4.18,t score of injury =8.35,10.31,5.94,9.66 and 8.15 ; all P＜0.05).The score of injury of high dose sinomenine group,high dose sinomenine combined group and SASP group was 1.40 ±± 1.26,1.70 ± 1.06 and 1.80 ± 1.32,respectively,which were lower than that of model group (3.00 ± 1.05) and the differences were statistically significant (t ＝ 3.07,2.75 and 2.25,all P＜0.05).The expression of MKK5,ERKS,MKK7,JNK and NF-κB at mRNA level of SASP group was 24.29±3.40,34.74±3.05,21.34±3.74,18.71±4.12 and 21.68±2.96,respectively,all were lower than those of low dose sinomenine group (51.94±9.16,50.71±11.09,57.98±17.22,55.99±9.65 and 67.41±10.21) and low dose sinomenine combined group (72.03±17.44,119.91±47.26,74.09±21.24,71.83±16.91 and 86.51±18.61).However,those of SASP group were higher than those of high dose sinomenine group (6.53±0.85,17.87±2.74,13.52±2.56,10.41±2.62 and 13.79± 1.43) and high dose sinomenine combined group (16.80±7.15,21.09±3.92,15.81±1.35,14.11±3.10 and 16.62±3.15).All of low dose sinomenine group were higher than those of high dose sinomenine group,all of low dose sinomenine combined group were higher than those of high dose sinomenine combined group,all of low dose sinomenine combined group were higher than those of low dose sinomenine group and all of high dose sinomenine combined group were higher than those of high dose sinomenine group and the differences were statistically significant (tMKK5=8.95,8.49,16.01,2.99,15.61,9.26,3.22 and 4.51,tERK5=4.41,5.69,13.02,12.81,7.82,6.78,4.50 and 2.13,tMKK7 =6.58,7.73,5.80,4.40,8.11,6.32,1.86 and 2.94,tJNK=10.59,7.57,5.37,2.82,13.21,7.57,2.57 and 2.88,tNF-κB =13.60,10.88,7.60,3.70,16.44,11.71,2.85 and 2.59 ; all P＜0.05).Conclusions Sinomenine can efficiently improve the inflammatory reaction in the mouse model of colitis and the mechanism may be related with ERK5,JNK and NF-κB signaling pathways.The higher the dose,the more significant the efficacy.The antagonism may exist between sinomenine and SASP.