Protective effect of Periplaneta americana extract in ulcerative colitis rats induced by dinitrochlorobenzene and acetic acid.
BACKGROUND
Periplaneta americana L. (Dictyoptera; Blattaria) has been traditional used to treat ulcers, burns and heart disease in southwestern China. Recent reports indicate that P. americana can be used as an alternative medicine in therapy of ulcerative colitis, but the mechanism involved remains obscure.


OBJECTIVE
This study investigated the therapeutic effect of P. americana extract (PAE) in rat colitis and elucidated its potential mechanism.


METHODS
Dinitrochlorobenzene and acetic acid-induced colitis rat model was applied. Colitis rats were treated with PAE for 10 d and estimated disease activity index daily. Rectal inflammation was assessed by myeloperoxidase activity and histological changes. Another colitis rats were treated with PAE for 4 d, meanwhile gavage with Escherichia coli labelled with green fluorescent protein. Mesenteric lymph nodes, colon, liver, spleen and kidney were harvested for bacteria culture. PAE was suspended in distilled water then partitioned with ethyl acetate and n-butanol to obtain ethyl acetate fraction, n-butanol fraction and water fraction, respectively. Fibroblasts proliferation and collagen accumulation of each fraction was determined.


RESULTS
PAE treatment reduced the severity of colitis and tissue myeloperoxidase accumulation (p < 0.001). Also, PAE at 80 mg/kg significantly inhibited labelled E. coli from translocating to distant organs, especially to MLN and liver. Additionally, PAE significantly stimulated fibroblasts proliferation (126.9%) and collagen accumulation (130.8%) for 48 h incubation. Among the partitions, ethyl acetate fraction generally had higher fibroblast viability enhanced-activity.


CONCLUSIONS
PAE can protect against ulcerative colitis and this protection is attributed to anti-inflammation and fibroblasts viability.
a Department of Pharmacy , Jiangsu University , Zhenjiang , Jiangsu , China.
Na
N
Li
b Department of Medicine , Jiangsu University , Zhenjiang , Jiangsu , China.
Rongzhu
R
Lu
a Department of Pharmacy , Jiangsu University , Zhenjiang , Jiangsu , China.
Yuanyuan
Y
Yu
a Department of Pharmacy , Jiangsu University , Zhenjiang , Jiangsu , China.
Ying
Y
Lu
a Department of Pharmacy , Jiangsu University , Zhenjiang , Jiangsu , China.
Lu
L
Huang
a Department of Pharmacy , Jiangsu University , Zhenjiang , Jiangsu , China.
Juan
J
Jin
a Department of Pharmacy , Jiangsu University , Zhenjiang , Jiangsu , China.
Lidan
L
Zhang
a Department of Pharmacy , Jiangsu University , Zhenjiang , Jiangsu , China.
Jun
J
Chen
D019342:Acetic Acid; D000818:Animals; D003093:Colitis, Ulcerative / Q000139:chemically induced / Q000473:pathology / Q000517:prevention & control*; D003094:Collagen / Q000096:biosynthesis; D000529:Complementary Therapies; D004137:Dinitrochlorobenzene; D008297:Male; D051379:Mice; D041681:NIH 3T3 Cells; D010526:Periplaneta; D009195:Peroxidase / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D012007:Rectum / Q000473:pathology
D004137:Dinitrochlorobenzene; D003094:Collagen; D009195:Peroxidase; D019342:Acetic Acid
Bacterial translocation; Escherichia coli; cockroach; ethnomedicine; fibroblast; green fluorescent protein; medical entomology