Objective To observe the effect of moxibustion at different duration on colonic mucosal morphological changes

serum and colonic cytokine levels in ulcerative colitis(UC)rats

so as to provide experimental evidence for clinical treatment of UC.Methods SD rats were randomly divided into blank control

UC model

3cones-moxibustion(3-cones-M)

6-cones-M and 9-cones-M groups

with 6rats in each group.UC model was established by intra-rectal injection of mixture solution of5%trinitro-benzene-sulfonic acid(TNBS

100mg/kg)and 50% alcohol(1∶1)under anesthesia and oral administration of 5%dextran sodium sulfate.Moxibustion(ignited moxa cones)was applied to"Tianshu"(ST 25)and"Daheng"(SP 15)

once daily in the first 7days

and once every other day in the subsequent 14days.Serum IL-8and IL-10contents were assayed by ELISA and colonic toll-like receptor 9(TLR-9)and nuclear factor-κB p 65(NF-κB p 65)protein expression levels detected by Western blot.The colonic mucosal structure was observed by light microscope after H.E.staining

and by electron microscope

respectively.Results In comparison with the blank control group

the Disease Activity Index(DAI)

serum IL-8content

colonic TLR-9and NF-κB p 65protein expression levels were significantly increased in the model group(P<0.05)

and serum IL-10content was notably decreased in the model group(P<0.05).While in comparison with the model group

the DAI

serum IL-8content

colonic TLR-9and NF-κB p 65protein expression levels in the 3-cones-M

6-cones-M and 9-cones-M groups were remarkably down-regulated(P<0.05)

and serum IL-10contents considerably up-regulated in the three moxibustion groups(P<0.05).No significant differences were found among the three moxibustion groups in the DAI(P>0.05).The serum IL-8contents were significantly lower and serum IL-10contents were considerably higher in the 6-cones-M and 9-cones-M groups than in the 3-cones-M group(P<0.05).The changes of colonic TLR-9and NF-κB p 65protein expression were more remarkable in the 9-cones-M group than in the 3-cones-M and 6-cones-M groups(P<0.05).Results of H.E.staining and electron microscopy showed that in the model group

mucosal injury

partial disorganization of the glandular organ

edema and congestion and inflammatory cell infiltration

mucosal epithelial microvili injury with disordered arrangement

etc.under light microscope

and local mucosal defect

apoptotic bodies and mucolysis under electron microscope were found

these situations were obviously lighter in rats of the three moxibustion groups

particularly in the 9-cones-M group.Conclusion Moxibustion intervention can relieve colonic mucosal injury in UC mice

which may be closely associated with its effects in suppressing serum proinflammatory cytokine IL-8

up-regulating anti-inflammatory cytokine IL-10level

and inhibiting colonic NF-κB p 65and TLR-9protein expression

and the effects of longer duration of moxibustion are better.