This study aims to observe the therapeutic effect of salidroside on cerebral ischemia-reperfusion(I/R) model rats, and to specifically explore the protection of salidroside on endothelial cell barrier after I/R and the mechanism. In the experiment, SD rats were randomized into sham group, model group, and high-, medium-, and low-dose(10, 5, and 2.5 mg·kg~(-1)) salidroside groups. The suture method was used to induce I/R in rats. The infarct area, neurobehavioral evaluation, and brain water content were used to evaluate the efficacy of salidroside. As for the experiment on the mechanism, high-dose and low-dose salidroside groups were designed. The pathological morphology was observed based on hematoxylin and eosin(HE) staining, and ultrastructure of vascular endothelial cells based on transmission electron microscopy. The content of nitric oxide(NO) in serum, four indexes of blood coagulation, and the content of von Willebrand factor(vWF) in plasma were measured. Western blot(WB) and immunofluorescence(IF) were employed to determine the expression of tight junction proteins(ZO-1, occluding, and claudin-1) and matrix metalloproteinase 9(MMP-9) in the cortex. The results showed that the model group had obvious neurological deficit, obvious infarct in the right brain tissue, and significant increase in water content in brain tissue compared with the sham group. Compared with the model group, high-dose and low-dose salidroside groups showed decrease in neurobehavioral score, and the high-, medium-, and low-dose salidroside groups demonstrated obviously small infarct area and significant decrease in water content in brain tissue. The results of HE staining and transmission electron microscopy showed that rats had necrosis of neurons, damage of original physiological structure of endothelial cells, and disintegration of the tight junction between endothelial cells after I/R compared with the sham group. Compared with the model group, the high-dose and low-dose salidroside groups showed alleviation of neuron injury and intact physiological structure of endothelial cells. The model group had significantly lower serum level of NO, significantly higher plasma levels of vWF and fibrinogen(FIB), and significantly shorter thrombin time(TT) and prothrombin time(PT) than the sham group. Compared with model group, the high-dose and low-dose salidroside groups increased the serum content of NO in serum, decreased the plasma levels of FIB and vWF, and significantly prolonged TT and PT. WB and IF results showed that the model group had significantly lower levels of ZO-1, occluding, and claudin-1 among endothelial cells and significantly higher level of MMP-9 than the sham group. Compared with the model group, high-dose and low-dose salidroside significantly increased the levels of ZO-1, occluding, and claudin-1 in the cortex. The above experimental results show that salidroside has clear therapeutic effect on I/R rats and protects the brain. To be specific, it alleviates the damage of endothelial cells by increasing NO synthesis in endothelial cells, inhibiting coagulation reaction and MMP-9 expression, up-regulating the expression of ZO-1, occludin, and claudin-1, thereby protecting the brain.
Animals ; Rats ; Matrix Metalloproteinase 9/metabolism* ; Endothelial Cells/metabolism* ; Reperfusion Injury/metabolism* ; Blood-Brain Barrier ; Claudin-1/therapeutic use* ; von Willebrand Factor/therapeutic use* ; Rats, Sprague-Dawley ; Brain Ischemia/metabolism* ; Cerebral Infarction ; Reperfusion ; Water/metabolism*

BACKGROUNDLeakage of the intestinal mucosal barrier may cause translocation of bacteria, then leading to multiorgan failure. This study hypothesized that rhubarb monomers might protect the gut mucosal barrier in sepsis through junction proteins.

METHODSHealthy male Sprague-Dawley rats (weighing 230-250 g) under anesthesia and sedation were subjected to cecal ligation and perforation (CLP). After surgical preparation, rats were randomly assigned to eight groups (n = 6 or 8 each group): sham group (Group A: normal saline gavage); sepsis group (Group B: normal saline gavage); Group C (intraperitoneally, dexamethasone 0.5 mg/kg) immediately after CLP surgery; and rhubarb monomer (100 mg/kg in normal saline)-treated groups (Group D: rhein; Group E: emodin; Group F: 3,8-dihydroxy-1-methyl-anthraquinone-2-carboxylic acid; Group G: 1-O-caffeoyl-2-(4-hydroxy-O-cinnamoyl)-D-glucose; and Group H: daucosterol linoleate). Animals were sacrificed after 24 h. Intestinal histology, lactulose, mannitol concentrations were measured, and zonula occludens (ZO)-1, occludin and claudin-5 transcription (polymerase chain reaction), translation (by Western blot analysis), and expression (by immunohistochemistry) were also measured.

RESULTSIntestinal histology revealed injury to intestinal mucosal villi induced by sepsis in Group B, compared with Group A. Compared with Group A (0.17 ± 0.41), the pathological scores in Groups B (2.83 ± 0.41, P < 0.001), C (1.83 ± 0.41, P < 0.001), D (2.00 ± 0.63, P < 0.001), E (1.83 ± 0.41, P < 0.001), F (1.83 ± 0.75, P < 0.001), G (2.17 ± 0.41, P < 0.001),and H (1.83 ± 0.41, P < 0.001) were significantly increased. Lactulose/mannitol (L/M) ratio in Group B (0.046 ± 0.003) was significantly higher than in Group A (0.013 ± 0.001, P< 0.001) while L/M ratios in Groups C (0.028 ± 0.002, P< 0.001), D (0.029 ± 0.003, P< 0.001), E (0.026 ± 0.003, P< 0.001), F (0.027 ± 0.003, P< 0.001), G (0.030 ± 0.005, P< 0.001), and H (0.026 ± 0.002, P< 0.001) were significantly lower than that in Group B. ZO-1, occludin and claudin-5 transcription, translation, and expression in Group B were significantly lower than that in Group A (P < 0.001), but they were significantly higher in Groups C, D, E, F, G, and H than those in Group B (P < 0.05).

CONCLUSIONRhubarb monomer treatment ameliorated mucosal damage in sepsis via enhanced transcription, translation, and expression of junction proteins.

Animals ; Claudin-5 ; metabolism ; Intestinal Mucosa ; drug effects ; metabolism ; Lactulose ; metabolism ; Male ; Mannitol ; metabolism ; Occludin ; metabolism ; Plant Extracts ; chemistry ; therapeutic use ; Rats ; Rats, Sprague-Dawley ; Rheum ; chemistry ; Sepsis ; drug therapy ; metabolism ; Zonula Occludens-1 Protein ; metabolism

Cold-heat combination is a common method in the treatment of ulcerative colitis, which is represented by classic drug pair, Coptidis Rhizoma and Zingiberis Rhizoma.The present study explored the synergetic effects of berberine and 6-shogaol, the primary components of Coptidis Rhizoma and Zingiberis Rhizoma, respectively, on intestinal inflammation and intestinal flora in mice with ulcerative colitis to reveal the effect and mechanism of cold-heat combination in the treatment of ulcerative colitis.The ulcerative colitis model was induced by dextran sulfate sodium(DSS) in mice.The model mice were administered with berberine(100 mg·kg~(-1)), 6-shogaol(100 mg·kg~(-1)), and berberine(50 mg·kg~(-1)) combined 6-shogaol(50 mg·kg~(-1)) by gavage, once per day.After 20 days of drug administration, mouse serum, colon tissues, and feces were sampled.Hematoxylin-eosin(HE) staining was used to observe histopathological changes in colon tissues.Alcian blue/periodic acid-Schiff(AB/PAS) staining was used to observe the changes in the mucus layer of colon tissues.Enzyme-linked immunosorbent assay(ELISA) was employed to detect the serum content of tumor necrosis factor-α(TNF-α), interleukin-1β(IL-1β), and interleukin-6(IL-6).Immunohistochemical method was adopted to detect the protein expression of macrophage surface markers F4/80, mucin-2, claudin-1, and zonula occludens-1(ZO-1) in colon tissues.High-throughput Meta-amplicon library sequencing was used to detect changes in the intestinal flora of mice.The results indicated that the 6-shogaol group, the berberine group, and the combination group showed significantly relieved intestinal injury, reduced number of F4/80-labeled positive macrophages in colon tissues, increased protein expression of mucin-2, claudin-1, and ZO-1, and decreased serum le-vels of TNF-α, IL-1β, and IL-6.Shannon, Simpson, Chao, and Ace indexes of the intestinal flora of mice in the 6-shogaol group and the combination group significantly increased, and Chao and Ace indexes in the berberine group significantly increased.As revealed by the bioinformatics analysis of intestinal flora sequencing, the relative abundance of Verrucomicrobia at the phylum, class, and order levels decreased significantly in all treatment groups after drug administration, while that of Bacillibacteria gradually increased.In the 6-shogaol group and the combination group, Akkermansia muciniphila completely disappeared, but acid-producing bacillus still existed in large quantities.As concluded, both 6-shogaol and berberine can inhibit intestinal inflammation, reduce the infiltration and activation of macrophages, relieve intestinal damage, reduce intestinal permeability, improve the structure of flora, and promote intestinal microecological balance.The combined application of berberine and 6-shogaol has a significant synergistic effect.
Animals ; Berberine/therapeutic use* ; Catechols ; Claudin-1/therapeutic use* ; Colitis/metabolism* ; Colitis, Ulcerative/metabolism* ; Colon ; Dextran Sulfate/metabolism* ; Disease Models, Animal ; Drugs, Chinese Herbal/pharmacology* ; Inflammation/metabolism* ; Interleukin-6/metabolism* ; Mice ; Mice, Inbred C57BL ; Mucin-2/pharmacology* ; Tumor Necrosis Factor-alpha/metabolism*