Effects of hydrogen sulfide on renal fibrosis in diabetic rats and its mechanism / 中国应用生理学杂志

OBJECTIVE@#To investigate the effects of hydrogen sulfide (HS) on renal fibrosis in diabetic rats and explore its mechanism.@*METHODS@#Male Sprague-Dawley rats were randomly divided into normal control (NC) group, a diabetic control (DC) group, diabetes mellitus (DM)+sodium hydrosulfide (NaHS) group and DM+DL-propargylglycine (PAG) group, with 8 rats in each group.Type 1 diabetes was induced in the respective groups by a single intraperitoneal (i.p.) injection of streptozotocin.From the fifth week, rats in the DM+NaHS and DM+PAG groups were injected (i.p.) with 56 μmol/kg NaHS and 40 mg/kg PAG once a day, respectively.After treatment for 4 weeks, the levels of fasting blood glucose (FBG), blood urea nitrogen (BUN) and serum creatinine (SCr) were detected.The deposition of renal collagen fibers was observed by Masson staining, and collagen volume fraction (CVF) was calculated.The ultrastructural change of renal tissue was observed by transmission electron microscopy.The levels of interleukin-1β (IL-1β), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and hydroxyproline (Hyp) in renal tissues were detected using the kits.The expression levels of TGF-β1, Smad3, phosphorylated (p)-Smad3 and collagen-IV (col-IV) in renal tissues were detected using Western blot.@*RESULTS@#Compared with the NC group, the levels of FBG, BUN, SCr, CVF, IL-1β, IL-6, TNF-α and Hyp were increased; the deposition of renal collagen fibers and the ultrastructural damage were aggravated; the levels of TGF-β1, Smad3, p-Smad3, p-Smad3/Smad3 and col-IV were increased in the DC group.Compared with the DC group, excluding FBG, the aforementioned indices were improved in the DM+NaHS group; the aforementioned indices were further aggravated in the DM+PAG group.@*CONCLUSIONS@#HS attenuated renal fibrosis in diabetic rats, and the mechanism might be associated with the reduction of the release of proinflammatory cytokines, downregulation of the TGF-β1/Smad3 pathway, and inhibition of excessive accumulation of col-IV.

Immunization with catalase and UreB two-valence vaccine for preventing Helicobacter pylori infection in mice / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effects of the two-valence vaccine consisting of Helicobacter pylori (H. pylori) catalase and urease subunit UreB in preventing H. pyloriinfection in mice.</p><p><b>METHODS</b>C57BL/6 mice were divided into 7 groups and immunized with intragastric administration of catalase and UreB (both 100 microg) plus cholera toxin (CT, 2 microg), catalase (100 microg) plus CT (2 microg), UreB (100 microg) plus CT (2 microg), catalase (100 microg), UreB (100 microg), CT (2 microg), or PBS, respectively, once a week for 4 consecutive weeks. Two weeks after the last immunization, all the mice were challenged by live H. pylori, and sacrificed 4 weeks after the challenge to obtain the gastric mucosa samples for detecting H. pylori using semi-quantitative bacterial culture assay.</p><p><b>RESULTS</b>The total protection rate in mice immunized with the two-valence vaccine, single-valence vaccine of catalase, and single-valence vaccine of UreB was 83.3% (20/24), 41.7% (10/24) and 54.2% (13/24), respectively, and the rate in the other 4 groups were all 0. The H. pyloricolony density in mice with vaccination was significantly lower than that of other 4 groups (P<0.05). The total protection rate and H. pylori colony density differed significantly between the two-valence vaccination group and the single-valence vaccination groups (P<0.05).</p><p><b>CONCLUSION</b>The two-valence vaccine consisting of catalase, UreB and adjuvant has better immunoprotective effects than the single-valence vaccines.</p>