RESUMO
Objective: To observe the effect of moxibustion on the colonic mucosal barrier of rats with ulcerative colitis (UC) induced by dextran sulfate sodium (DSS). Methods: Forty male Sprague-Dawley rats were randomly divided into a normal group and a modeling group, with 20 rats in each group. Rats in the modeling group were subjected to preparing experimental UC models by drinking 4％ DSS for seven consecutive days. Two modeled rats and two normal rats were randomly selected for model identification. After the success of UC model was confirmed, the remaining 18 modeled rats were randomly divided into three groups, a model group, a model + herbal cake-partitioned moxibustion group, and a model + mild moxibustion group, with six rats in each group; the remaining normal rats were randomly divided into three groups, a normal group, a normal + herbal cake-partitioned moxibustion group, and a normal + mild moxibustion group, with six rats in each group. After 7 d of intervention with the herbal cake-partitioned moxibustion or the mild moxibustion, hematoxylin-eosin (HE) staining technique was used to observe the pathological changes of colon tissue under a light microscope; Western blotting and/or immunohistochemical techniques were used to detect the protein expression levels of Occludin, Claudin, junction adhesion molecular 1 (JAM1), mucin 2 (MUC2), and transforming growth factor beta1 (TGF-β1) in rat colon tissue. Results: Compared with the normal group, the colon tissue was severely damaged, the pathological score was significantly increased, and the protein expression levels of Occludin, Claudin, JAM1, MUC2, and TGF-β1 were significantly decreased in the model group (P<0.01); while there were no significant differences in the colonic histopathological score, protein expression levels of Occludin, Claudin, JAM1, MUC2, and TGF-β1 in the normal + herbal cake-partitioned moxibustion group and the normal + mild moxibustion group (P>0.05). Compared with the model group, the model + herbal cake-partitioned moxibustion group and the model + mild moxibustion group showed repaired colon tissue, ulcer healing, significantly reduced pathological score, and significantly increased protein expression levels of JAM1, MUC2, and TGF-β1 (P<0.05); the Occludin protein expression level in the colon tissue of the model + mild moxibustion group was increased (P<0.01). Conclusion: Neither herbal cake-partitioned moxibustion nor mild moxibustion influences the colonic histopathology and intestinal mucosal barrier-related protein expression in the normal rats; both herbal cake-partitioned moxibustion and mild moxibustion can up-regulate the protein expression levels of JAM1, MUC2, and TGF-β1 in the colon tissue of UC rats. Mild moxibustion can up-regulate Occludin protein expression. This may be a mechanism of moxibustion in reducing colonic mucosa inflammation in UC.
RESUMO
Dengue virus (DENV) envelope [E] protein is the major surface protein of the virions that indued neutralizing antibodies. The domain III of envelope protein (EDIII) is an immunogenic region that holds potential for the development of vaccines; however, the epitopes of DENV EDIII, especially neutralizing B-cell linear epitopes, have not been comprehensively mapped. We mapped neutralizing B-cell linear epitopes on DENV-1 EDIII using 27 monoclonal antibodies against DENV-1 EDIII proteins from mice immunized with the DENV-1 EDIII. Epitope recognition analysis was performed using two set of sequential overlapping peptides (16m and 12m) that spanned the entire EDIII protein from DENV-1, respectively. This strategy identified a DENV-1 type- specific and a group-specific neutralizing epitope, which were highly conserved among isolates of DENV-1 and the four DENV serotypes and located at two regions from DENV-1 E, namely amino acid residues 309-320 and 381-392(aa 309-320 and 381-392), respectively. aa310 -319(310KEVAETQHGT319)was similar among the four DENV serotypes and contact residues on aa 309 -320 from E protein were defined and found that substitution of residues E309 , V312, A313 and V320 in DENV-2, -3, -4 isolates were antigenically silent. We also identified a DENV-1 type-specific strain-restricted neutralizing epitope, which was located at the region from DENV-1 E, namely amino acid residues 329-348 . These novel type- and group-specific B-cell epitopes of DENV EDIII may aid help us elucidate the dengue pathogenesis and accelerate vaccine design.