Clinical significance of monitoring parathyroid hormone in drainage fluid and serum after total thyroidectomy / 中华内分泌外科杂志

Objective:To observe the effect of different clinical factors on the level of parathyroid hormone (PTH) and to predict the possibility of permanent hypothyroidism (PHP) after total thyroidectomy (TT) by monitoring the levels of PTH in serum and drainage fluid after TT.Methods:Retrospective analysis was made on 150 patients who underwent TT for papillary thyroid carcinoma (PTC) in the Department of Thyroid Head and Neck Surgery in Jilin Cancer Hospital from Jan. 2020 to Aug. 2021. The changes of serum PTH were recorded at 1, 3, 7, 30 days and 6 months after surgery. The risk factors of postoperative hypoparathyroidism (HP) were investigated by single factor and multi factor methods. The impairment of parathyroid function was predicted combined with the level of PTH in the drainage fluid 1 day after operation.Results:After TT, serum PTH returned to normal value in most patients 1 month after operation. The proportion of PHP was 3.33% (5/150). Univariate analysis showed that bilateral central lymph node dissection, Hashimoto’s thyroiditis, tumor diameter ≥2 cm and intraoperative selective parathyroid autologous transplantation were risk factors for temporary hypoparathyroidism (THP). Multivariate analysis showed that BCND ( OR=0.322, P=0.001) , intraoperative selective parathyroid autograft ( OR=5.442, P=0.001) and tumor diameter ≥2 cm ( OR=2.247, P=0.003) were independent risk factors for THP. ROC curve was used to compare the predictive effect of postoperative serum and drainage PTH levels on postoperative PHP. The statistical results showed that the highest predictive effect of postoperative PHP was found on the first day of drainage PTH level within 1 week after operation (AUC 0.81) . 54 cases whose serum PTH was lower than normal value on the first day after operation were divided into 4 groups according to the level of PTH in drainage fluid from high to low. The results showed that the lower the level of PTH in drainage fluid, the greater the possibility of PHP ( P<0.05). Conclusions:Most of the patients with low PTH one month after operation develop PHP, while bilateral central lymph node dissection, intraoperative selective parathyroid transplantation, tumor diameter ≥2 cm are risk factors for THP after TT. If the serum PTH is lower than the normal value on the first day after operation, there is a possibility of PTH. The lower the PTH in the drainage fluid, the greater the possibility of PHP, which should be paid attention to in clinical practice.

Effects of compound fermented milk on improving constipation in mice and underlying mechanism / 中华微生物学和免疫学杂志

Objective:To investigate the effects of compound fermented milk on intestinal microbiota, short chain fatty acid (SCFA), intestinal motility and mucosal barrier in mice with constipation.Methods:Twenty-seven C57BL/6JNifdc mice were randomly divided into three groups: control group, model group and intervention group. The model group and the intervention group were given loperamide intragastrically for two weeks. Starting from the second week, the intervention group was treated with compound fermented milk for 7 d. The control group was given normal saline. Food intake, water intake, weight change, fecal moisture content, time of first-time black stool and small intestine propulsion rate were detected. Expression of serotonin C receptor (5-HTR2C), zona occludins-1 (ZO-1) and mucin-2 (MUC-2) at mRNA level in colon was analyzed. Western blot was used to measure the expression of Raf/ERK/MAPK-related proteins. SCFA level in intestinal tract was detected by gas chromatography. Intestinal microbiota diversity was analyzed by high-throughput sequencing.Results:Compared with the control group, the first black stool excretion time was significantly prolonged in the model group ( P<0.01). Moreover, fecal moisture content, small intestine propulsion rate and the expression of 5-HTR2C and ZO-1 at mRNA level in colon were significantly decreased ( P<0.01). Compared with the model group, the first black stool excretion time was significantly shortened ( P<0.05); fecal moisture content, small intestine propelling rate ( P<0.05), the expression of colon 5-HTR2C and ZO-1 at mRNA level ( P<0.05), phosphorylation of Raf/ERK/MAPK pathway in the colon, intestinal SCFA-producing bacteria and intestinal SCFA content were increased in the intervention group. Conclusions:Compound fermented milk had a therapeutic effect on constipation in a mouse model by increasing the abundance of SCFA-producing bacteria and SCFA content, enhancing the phosphorylation of the Raf/ERK/MAPK pathway to up-regulate the expression of 5-HTR2C at mRNA level in the colon, and increasing the expression of ZO-1 at mRNA level in the colon. Intestinal peristalsis and intestinal mucosal barrier function were enhanced, thus improving the symptom of constipation.

Correlation analysis of gut microbiota and biochemical indexes in patients with non-alcoholic fatty liver disease / 中华肝脏病杂志

Objective@#To investigate the relationship between gut microbiota structure and biochemical changes in patients with different types of nonalcoholic fatty liver disease (NAFLD), in order to provide evidence for clinical diagnosis and prevention of NAFLD.@*Methods@#Forty-eight NAFLD cases (NAFLD group), 40 NAFLD cases with type 2 diabetes mellitus (NAFLD combined with type 2 diabetes mellitus group) and 30 healthy cases (healthy group) were randomly enrolled, and their body mass index, serum alanine aminotransferase, aspartate aminotransferase, total bilirubin, total cholesterol, triglyceride, high density lipoprotein, low density lipoprotein and uric acid were measured. Serum levels of TNF-alpha and fasting insulin were measured using ELISA, and then insulin resistance index was calculated. The gut microbiota of three groups of subjects was detected using 16S rDNA-based high-throughput sequencing. Lastly, the correlations between the various factors were analyzed. The comparison among groups was conducted by 2 test, and one-way ANOVA was used for comparison among groups with normal distribution and homogeneity of variance. Furthermore, the LSD method was used to compare the two groups. K-W rank sum test was used for comparison among groups without normal distribution or homogeneity of variance.@*Results@#Body mass index, aspartate aminotransferase, triglyceride, total cholesterol, low density lipoprotein, uric acid, tumor necrosis factor-alpha, fasting insulin and insulin resistance index of NAFLD group were higher than healthy group, while the high-density lipoprotein was lower in the healthy group, and the difference was statistically significant (P< 0.05). Compared with NAFLD group, the life expectancy, fasting blood glucose and insulin resistance index of NAFLD combined with type 2 diabetes mellitus group were higher, while the body mass index, aspartic acid aminotransferase, total cholesterol and HDL levels were decreased, and the difference was statistically significant (P< 0.05). NAFLD group (P= 0.016) had decreased abundance of firmicutes than healthy group, and the abundancy of the firmicutes in the NAFLD combined with type 2 diabetes group was significantly lower (P< 0.001). The abundance of bacteroidetes in NAFLD combined with type 2 diabetes group was higher than healthy group, and the difference was statistically significant (P= 0.006). At the "genus level," the abundance of Roseburia and Subdoligranulum in the NAFLD group was decreased, while the Roseburia in the NAFLD group with type 2 diabetes group was significantly lower (P< 0.05). In addition, the abundance of Faecalibacterium, Blautia, Anaerostipes and Fusicatenibacter in NAFLD combined with type 2 diabetes group was lower than healthy group, and the difference was statistically significant (P< 0.001). Fusicatenibacter, Blautia, Anaerostipes, Faecalibacterium, and Roseburia were negatively correlated with fasting blood glucose and insulin resistance index levels (r< 0,P< 0.05), and positively correlated with high-density lipoprotein levels (r> 0,P< 0.05). Fusicatenibacter was negatively correlated with tumor necrosis factor-alpha (r= -0.211,P= 0.044), and Lachnoclostridium was positively correlated with body mass index, alanine aminotransferase, aspartate aminotransferase levels (r> 0,P< 0.05). Fusobacterium was positively correlated with aspartate aminotransferase level (r= 0.245,P= 0.019). Escherichia-shigella was positively correlated with fasting blood glucose, low-density lipoprotein, alanine aminotransferase, aspartate aminotransferase levels (r > 0,P< 0.05). Megamonas was negatively correlated with high-density lipoprotein levels (r= -0.231,P= 0.027).@*Conclusion@#A structural change of gut microbiota had occurred in patients with NAFLD, suggesting changes in some of these bacterial genuses had relation to insulin resistance and inflammatory response, which may become a new target for the treatment of NAFLD.

Effects of cholesterol-lowering probiotics on intestinal barrier and gut microbiota in mice with non-alcoholic fatty liver disease and the possible mechanisms / 中华微生物学和免疫学杂志

Objective To investigate the effects of cholesterol-lowering probiotics, DM9054 com-bined with 86066, on the intestinal mucosal barrier and gut microbiota in mice with nonalcoholic fatty liver disease ( NAFLD) induced by high-fat diet and the possible mechanisms. Methods Twenty-four male mice deficient in the low-density lipoprotein receptor gene ( Ldlr- / - mice ) were randomly divided into three groups including control, NAFLD model and probiotic intervention groups. Mice in the three groups were given normal chow diet+normal saline, high-fat diet ( HFD)+normal saline, and HFD+cholesterol-lowering probiotics, respectively. The mouse model of NAFLD was established by feeding mice with high-fat diet (45％ of calories derived from fat diet) for 12 weeks. qPCR was performed to measure the expression of liv-er and intestinal inflammatory genes and liver cholesterol synthesis genes. Western blot assay was used to de-tect the expression of intestinal tight junction proteins and HMG-CoA reductase ( HMGCR ) . Pathological changes in tissues were evaluated by HE staining. Features of gut microbiota were analyzed by 16S rRNA gene sequencing. Results Cholesterol-lowering probiotics intervention attenuated HFD-induced hepatic steatosis, inflammatory responses and obesity and decreased the synthesis of liver cholesterol (P<0. 05). Moreover, inhibited gut inflammatory responses and improved intestinal barrier function were detected in the probiotic intervention group (P<0. 05). The composition of gut microbiota in mice of the probiotic intervention group was different from that of the model group, but similar to that of the control group. Con-clusions Cholesterol-lowering probiotics might attenuate NAFLD in mice through reducing liver cholesterol synthesis, alleviating liver and intestinal inflammation, improving intestinal mucosal barrier function and reg-ulating intestinal microbiota.

Helicobacter pylori virulence factor vacuolating cytotoxin A ( VacA) promotes homologous recombi-nation repair in GES-1 cells / 中华微生物学和免疫学杂志

Objective To analyze the impact of Helicobacter pylori standard strain (Hp P12) and its virulence factor vacuolating cytotoxin A ( VacA) on DNA damage and homologous recombination ( HR) repair in a human gastric epithelial cell line (GES-1). Methods Strains of Hp P12 and vacA gene knock-out Hp P12 ( Hp P12 ΔvacA) were respectively used to infect GES-1 cells at a multiplicity of infection of 100. GES-1 cells treated with etoposide (50μmol/L) or mitomycin (0. 5μg/ml) for 2 h were used as posi-tive control. Western blot and immunofluorescence were performed to detect the expression of DNA damage marker protein γH2AX and key HR repair proteins (Rad51, pMRE11, CtIP and pCtIP) and the recruitment of them at DNA damage sites. Human embryonic kidney HEK-293 ( DR-GFP) cells were infected with Hp P12 and Hp P12 ΔvacA strains to verify the impact of VacA on HR repair efficiency. Results The expres-sion and recruitment of γH2AX and key HR repair proteins ( Rad51, pMRE11, CtIP and pCtIP) were in-creased in Hp P12-infected cells as compared with that in uninfected and Hp P12 ΔvacA-infected cells ( all P<0. 05). To evaluate the HR repair efficiency, I-SceⅠ plasmid-transfected HEK-293 (DR-GFP) cells were infected with Hp P12 and Hp P12 ΔvacA and the results showed that green fluorescent protein ( GFP)-positive cells were decreased after infection, especially in Hp P12 ΔvacA-infected cells (both P<0. 05). Conclusions Hp P12 infection could cause DNA damage and promote HR repair in GES-1 cells, in which the virulence factor VacA played an important role.

Combined treatment with probiotics and fructooligosaccharides in a mouse model of nonalcoholic fatty liver disease and its possible mechanism / 中华微生物学和免疫学杂志

Objective To investigate the effectiveness of Lactobacillus paracasei N1115 combined with fructooligosaccharides (FOS) in the treatment of nonalcoholic fatty liver disease(NAFLD) in a mouse model and to analyze the possible mechanism.Methods Fifty male C57BL/6 mice were randomly divided into five groups and respectively given normal diet (ND group), high-fat diet (HFD group), HFD containing Lactobacillus paracasei N1115 (HFD+L) (2.2×109 CFU/ml), HFD containing FOS (HFD+FOS) (4 g/kg per day) and HFD containing Lactobacillus paracasei N1115 and FOS for 16 consecutive weeks.Levels of triglyceride (TG), total cholesterol (TC), low-density lipoprotein (LDL), high-density lipoprotein (HDL), lipopolysaccharide (LPS) and diamine oxidase (DAO) in serum samples from each group were measured.Expression of tight-junction proteins (Claudin-1 and Occludin), p38 and phosphorylated p38 (p-p38) in intestinal tissues were analyzed.Results Compared with the HFD group, the HFD+FOS+L group showed decreased levels of TC, TG, LDL, LPS and DAO in serum samples, but increased serum HDL level (P<0.05).Moreover, combined treatment with Lactobacillus paracasei N1115 and FOS alleviated liver lipid deposition, significantly increased the expression of Claudin-1 and Occludin in intestine and inhibited the phosphorylation of p38 (P<0.05).Conclusion Lactobacillus paracasei N1115 combined with FOS may increase the expression of Claudin-1 and Occludin through inhibiting the phosphorylation of intestinal p38, which is conducive to maintaining the intestinal mucosal barrier integrity and alleviating NAFLD.

Effects of clostridium butyricum on intestinal barrier function in food allergic mice / 重庆医学

Objective To investigate that butyrate-producing probiotic clostridium butyricum improves the intestinal epithelial barrier function in food allergic mice by regulating TWIK-related potassium channel-1 (Trek1) expression in intestinal epithelial cells.Methods An intestinal allergy mouse model was created,then the model construction effect was verified by detecting the related indicators by ELISA,flow cytometer.The change of small intestinal tissue permeability was detected by the Ussing chambers.The Trek1 expressions in mouse jejunum tissue in control group and allergy group were detected by Western blot and immunofluorescent method;in the Transwell system,T84 cells were used to establish epithelial cellular monolayer for exposing to the allergic mediators,the Trek1 mRNA and protein expression were detected by qRT-PCR and Western blot.Then the allergic mice were grouped and treated by different methods including normal saline,SIT,SIT/SB,SB,SIT/CB,CB,SIT/CB/Spadin,the expression of mice intestinal Trek1,intestinal barrier function and allergic reaction indicators were detected.Results Compared with the control group,the small intestinal Trek1 protein and tissue expression level in the food allergic mice were significantly decreased,the intestinal mucosal permeability was significantly increased,the differences were statistically significant(P＜0.05);after T84 cells exposing to the allergic mediators,Trek1 mRNA and protein expression were significantly decreased(P＜0.05),but adding p38 inhibitor in advance could antagonize this change;the single use of SIT,clostridium butyricum and sodium butyrate could increase the intestinal Trek1 expression in food allergic mice,and alleviated the allergic reaction(P＜0.05),whereas the combined use of SIT and clostridium butyricum or sodium butyrate had more significant effect(compared with the SIT group,P＜0.05),moreover could significantly decrease small intestinal mucosal permeability and improved the intestinal barrier function(P＜0.05).Conclusion Sodium butyrate or butyrate-producing probiotic clostridium butyricum can restore the intestinal barrier function,alleviates the allergic reaction and strengthens the SIT curative effect in allergic mice by increasing Trek1 expression.

CRF and CRF Receptors Expression in DSS Colitis Model in Mice / 医学研究杂志

Objective To detect the expression of CRF and CRF receptors in colonic mucosa of DSS induced colitis in mice model and to study the effect of CRF and CRF receptors on the development.Methods Six to eight weeks healthy female BALB/c mice were divided into control group and DSS group.Setting up DSS colitis model and colitis was evaluated by the disease activity index(DAI) and histological score.The immunofluorescence technique was used to assay the CRF1 and CRF2 receptors expression in colonic mucosa.The expression of CRF and CRF receptors protein were analyzed by western blotting.Results DSS colitis was set up successfully with significant inflammation in colonic mucosa by the disease activity index (DAI) and histological score.Immunofluorescenee staining evidenced that expression of CRF1 receptor in DSS colitis group has no significant deviation compared to control group(P ＞ 0.05),while the expression of CRF2 receptor was elevated in DSS colitis group compared to control group (P ＜ 0.05).CRF2 receptor was localized in epithelial cells and mononuclear cells in the lamina propria.The levels of CRF and CRF2 receptor protein by western blotting were higher in in DSS colitis group compared to control group (P ＜ 0.05).The level of CRF1 receptor protein in DSS colitis group had no significant deviation compared to control group(P ＞ 0.05).Conclusion The higher expression of CRF and CRF2 in colonic mucosa of DSS colitis may participate in the development of colitis.

Effects of Lactobacillus paracasei N1115 combined with fructooligosaccharides on non-alcoholic fatty liver disease induced by high-fat diet in mice / 中华肝脏病杂志

Objective@#To investigate the effects of Lactobacillus paracasei N1115 combined with fructooligosaccharides (FOS) on non-alcoholic fatty liver disease (NAFLD) in mice and its possible mechanism.@*Methods@#A total of 50 male C57 mice were randomly and equally divided into five experimental groups. Group 1 received a normal diet (ND). Other four groups received a high-fat diet (HFD) to establish NAFLD models. In addition to HFD, group 3 received Lactobacillus paracasei N1115 (2.2×109 CFU/mL), group 4 received FOS (4 g/kg per day), and group 5 received Lactobacillus paracasei N1115 (2.2×109 CFU/mL) and FOS (4 g/kg per day). All groups received continuous intervention for 16 weeks. The following indices were measured for all groups after intervention: general condition, the levels of fasting blood glucose, insulin, and lipopolysaccharide (LPS), and the levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, and interferon (IFN)-γ in the serum and liver. The mRNA levels of Toll-like receptor (TLR)4, nuclear factor (NF)-κb, insulin receptor (InsR), and insulin receptor substrate (IRS)-1 were measured by real-time RT-PCR. The data were subjected to one-way analysis of variance and comparison between groups was made by Bonferroni method.@*Results@#Compared with group 2, groups 3, 4, and 5 had significantly lower body weight, Lee's index, liver index, and the levels of blood glucose and insulin resistance (P < 0.05). The serum level of LPS in group 2 was significantly higher than that in the other experimental groups (group 1: 8.80 ± 0.85 U/L, group 3: 12.31 ± 1.01 U/L, group 4: 12.27 ± 0.98 U/L, and group 5: 10.17 ± 0.79 U/L vs group 2: 15.45 ± 1.14 U/L, F = 55.117, P < 0.001). The levels of TNF-α, IL-1β, IL-6, and IFN-γ in the serum and liver in group 2 were also significantly higher than those in the other groups (P < 0.05). Group 2 had significantly higher mRNA levels of TLR4 and NF-κb in the liver than the other groups (F = 82.933, P < 0.001; F = 149.033, P < 0.001); however, it had significantly lower mRNA levels of InsR and IRS-1 in the liver than the other groups (F = 33.347, P < 0.001; F = 70.225, P < 0.001).@*Conclusion@#Lactobacillus paracasei N1115 combined with FOS can reduce the level of LPS in the blood circulation, inhibit activation of the LPS/TLR4 signaling pathway, and reduce the release of inflammatory factor and the body's insulin resistance, so it can relieve NAFLD.

Correlation between Helicobacter pylori infection and primary infertility / 中华消化杂志

Objective To investigate whether Helicobacter pylori (H.pylori) infection correlated with primary infertility,whether H.pylori infection caused the abnormal elevation of pro-inflammatory cytokines in primary infertility women,and whether cytotoxin associated gene A (CagA) protein played a key role in it.Methods From September 2015 to August 2016,213 patients with primary infertility (infertility group) and 97 healthy individuals (control group) were selected.According to the common etiologies,patients with primary infertility were divided into groups with single-factor infertility,multifactorial infertility and unexplained reason groups.Serum H.pylori IgG antibody and CagA antibody were examined by H.pylori antibody type test kits.The levels of interleukin (IL)-2,IL-4,IL-5,IL-6,IL-8,IL-10,IL-13,IL-18,IL-1β,granulocyte-macrophage-colony stimulating factor (GM-CSF),interferon-γ (IFN-γ),tumor necrosis factor-a (TNF-a) and IL-12p70 were tested by ProcartaPlex Immunoassays.Chi square test and independent sample t test were performed for statistical analysis and risk was assessed.Results The positive rate of serum H.pylori IgG antibody of patients with primary infertility was higher than that of healthy control group (74.0％,37/50 vs 56.7％,55/97),and the difference was statistically significant (odds ratio (OR) =2.173,95 ％ confidence interval (CI) 1.028 to 4.595,x2=4.216,P =0.040).There was no statistically significant difference in the positive rate of CagA antibody between primary infertility group and healthy control group (71.7 ％,91/127 vs 74.5 ％,41/55,OR=0.863,95％CI0.421 to1.772,P＞0.05).The serum levels ofIL-8,IL-18 andIFN-γ of H.pylori positive primary infertility patients were (35.14 ± 12.16),(11.83 ± 4.01) and (11.05 ±3.17) ng/L,respectively,which were all higher than those of H.pylori positive healthy control group ((21.44±12.35),(9.89±2.23) and (8.90±1.45) ng/L,respectively) and H.pylori negative primary infertility group ((11.45±8.63),(7.90±0.99) and (8.18±1.10) ng/L,respectively),and the differences were statistically significant (t=6.947,3.366 and 4.811;15.596,8.900 and 8.068;all P＜0.05).The levels of IL-8,IL-18 and IFN-γ of H.pylori positive unexplained reason primary infertility group were (39.97 ± 11.52),(13.12±4.61) and (13.06±3.70) ng/L,respectively,which were all significantly higher than those of single-factor infertility group ((31.65 ±11.20),(11.12 ± 3.46) and (10.14 ± 2.41) ng/L,respectively) and multifactorial infertility group ((30.47±8.49),(11.13±3.79) and (10.07±2.50) ng/L,respectively);and the differences were statistically significant (t=4.217,2.942 and 5.738;5.138,2.562 and 5.218;all P＜0.05).In H.pylori positive primary infertility group,the levels of IL-8,IL-18 and IFN-γ of CagA positive patients were (40.42 ± 13.80),(13.04 ± 4.19) and (11.51± 3.41) ng/L,respectively,which were all significantly higher than those of CagA negative patients ((23.49 ± 11.57),(9.08 ± 1.43) and (10.04 ± 2.29) ng/L,respectively) and CagA positive individuals in healthy control group ((21.85 ± 12.14),(10.20 ± 2.29) and (9.31 ± 2.38) ng/L,respectively);and the differences were statistically significant (t =6.507,5.533 and 2.380;7.417,4.069 and 3.738;all P＜0.05).Conclusion CagA positive H.pylori infection can increase the level of serum pro-inflammatory cytokines,which may be a risk factor of primary infertility.To patients with unexplained primary infertility,this may be the cause of infertility.

Carnosic acid protects against acetaminophen-induced hepatotoxicity by potentiating Nrf2-mediated antioxidant capacity in mice

Acetaminophen (APAP) overdose is one of the most common causes of acute liver failure. The study aimed to investigate the protective effect of carnosic acid (CA) on APAP-induced acute hepatotoxicity and its underlying mechanism in mice. To induce hepatotoxicity, APAP solution (400 mg/kg) was administered into mice by intraperitoneal injection. Histological analysis revealed that CA treatment significantly ameliorated APAP-induced hepatic necrosis. The levels of both alanine aminotransferase (ALT) and aspartate transaminase (AST) in serum were reduced by CA treatment. Moreover, CA treatment significantly inhibited APAP-induced hepatocytes necrosis and lactate dehydrogenase (LDH) releasing. Western blot analysis showed that CA abrogated APAP-induced cleaved caspase-3, Bax and phosphorylated JNK protein expression. Further results showed that CA treatment markedly inhibited APAP-induced pro-inflammatory cytokines TNF-alpha, IL-1beta, IL-6 and MCP-1 mRNA expression and the levels of phosphorylated IkappaBalpha and p65 protein in the liver. In addition, CA treatment reduced APAP- induced hepatic malondialdehyde (MDA) contents and reactive oxygen species (ROS) accumulation. Conversely, hepatic glutathione (GSH) level was increased by administration of CA in APAP-treated mice. Mechanistically, CA facilitated Nrf2 translocation into nuclear through blocking the interaction between Nrf2 and Keap1, which, in turn, upregulated anti-oxidant genes mRNA expression. Taken together, our results indicate that CA facilitates Nrf2 nuclear translocation, causing induction of Nrf2-dependent genes, which contributes to protection from acetaminophen hepatotoxicity.

Effects of cholesterol-lowering probiotics on the metabolism of bile acid in a rat model of non-alcoholic fatty liver disease and the possible mechanism / 中华微生物学和免疫学杂志

Objective To investigate the effects of two cholesterol-lowering probiotics, DM9054 (Lac-tobacillus Rhamnosus GG, LGG) in combination with 86066 (Lactobacillus plantarum WCFS1, LP), on the metabolism of bile acid via a rat model of non-alcoholic fatty liver disease (NAFLD) and the possible mecha-nism. Methods Twenty-one SD male rats were randomly divided into three groups including control group, NAFLD model group and probiotics intervention group. Rats in the control group received normal diet. The rat model of NAFLD was established by feeding rats with chronic high fat diet (45% of calories derived from fat di-et) for 20 weeks. Rats in the probiotics intervention group were given high fat diet together with cholesterol-low-ering probiotics through oral gavage. General indexes of each group including body weight and the levels of tri-glyceride, cholesterol and CK18-M30 in serums samples were detected. The expression of cholesterol 7-alpha hydroxy-lase (CYP7A1), fibroblast growth factor receptor 4 (FGFR4), farnesoid X receptor (FXR), fibroblast grwoth factor 15 (FGF15) and apical sodium-dependent bile acid transparter(ASBT) at mRNA level were de-tected by using real-time polymerase chain reaction (real-time PCR). Western blot assay was used to detect the protein expression of CYP7A1, FXR in liver tissues and ASBT in ileum tissues. The expression of FXR in liver and ileum tissues were analyzed by immunohistochemistry. Results Rats with NAFLD showed loss of body weight and decreased levels of the serological markers after treating with the probiotics (P0. 05). Conclusion Probiotics intervention might up-regulate the expression of CYP7A1 by suppressing the FXR path-way in liver tissues and inhibiting the expression of ASBT in ileum tissues. Treating NAFLD rats with cholester-ol-lowering probiotics could activate the FXR-FGF15 pathway in ileum tissues and enhance the metabolism of bile acid, which contributed to the alleviation of NAFLD.

Effects of lactitol and Bifidobacterium infantis on AQP3 and ICC in a rat model of constipation / 中华微生物学和免疫学杂志

Objective To analyze the roles and mechanisms of lactitol and Bifidobacterium infantis in the treatment of rat constipation and to investigate their effects on aquaporin3 (AQP3) and interstitial cells of Cajal (ICC) in colon tissues.Methods Thirty SD male rats were recruited in this study,6 of which were randomly selected as the control and the rest were given 4 mg/kg.d of loperamide for 5 consecutive days to construct the rat model of constipation.The rats with constipation were randomly divided into four groups including model group,lactitol treatment group,Bifidobacterium infantis treatment group and lactitol in combination with Bifidobacterium infantis treatment group.General indexes including food intake,water intake,body weight,fecal water content and intestinal transit rate of each rat were measured after receiving corresponding treatments for 7 consecutive days.The levels of substance P (SP) and vasoactive intestinal peptide (VIP) in serums samples were detected by ELISA.The expression of protein kinase A (PKA) and neurokinin-1 receptor (NK-1) at mRNA level in colon tissues were detected by real-time polymerase chain reaction (real-time PCR).Western blot assay and real-time PCR analysis were used to detect the expression of AQP3 and c-kit at protein and mRNA levels,respectively.Results Compared with the rats in model group,the levels of fecal water content and intestinal transit rate,the concentrations of SP and VIP in serums samples,the expression of PKA and NK-1 at mRNA level and the expression of AQP3 and c-kit at mRNA and protein levels were significantly increased in rats from the three treatment groups (P＜0.05).The most effective treatment was lactitol in combination with Bifidobacterium infantis,followed by the lactitol treatment and then the Bifidobacterium infantis treatment.Conclusion The combination therapy with lactitol and Bifidobacterium infantis increased the serum levels of SP and VIP in rats with constipation.SP could enhance the contraction of gastrointestinal smooth muscles and improve the intestinal motility by binding to the NK-1 receptor on the membrane of ICC.VIP could promote the absorption of water in intestinal tracts,soften stools and alleviate constipation by upregulating the expression of AQP3 at both protein and mRNA levels via the cyclic adenosine monophosphate-PKA (cAMP-PKA) signaling pathway.

Effects of aryl hydrocarbon receptor on Th17 cells activation in a murine model of irritable bowel syndrome / 中华微生物学和免疫学杂志

Objective To detect the dynamic Th17 cells in a murine model of irritable bowel syn-drome ( IBS) and to study the effect of aryl hydrocarbon receptor ( Ahr) on Th17 cells activation .Methods Thirty BALB/c male mice were randomly divided into three groups including experiment group ,control group and Ahr antagonist group .A murine model of IBS was established by perfusing three nitrobenzene sulfonic acid (TNBS) into the colon of mice.Equal volume of saline was used to set up the control .The mice in Ahr antagonist group were intraperitoneally injected with 10 μg Ahr antagonist for four consecutive days .All mice were evaluated for visceral hypersensitivity and colonic mucosal inflammation .Mesenteric lymph nodes (MLNs) and peripheral blood mononuclear cells (PBMCs) were detected by flow cytometry through staining Th17 cells.The distribution of Ahr and IL-17A in colon and the number of Th17 cells activated by Ahr (Ahr and IL-17A double positive ) were detected by double immunofluorescence staining .Results ( 1 ) The percentage of Th17 cells in MLNs was significantly increased in experiment group followed by those in Ahr antagonist group and control group (P<0.05).(2)Compared with control group,the number of Th17 cells in peripheral blood samples was significantly increased in experiment group and Ahr antagonist group ( both P<0.05 ) ,but there was no difference between Ahr antagonist group and experiment group ( P=0.642 ) .( 3 ) The number of Ahr-activated Th17 cells ( Ahr+IL-17A+) was significantly increased in experiment group (10.00±1.58) as in comparison with that in control group (3.80±0.83,P<0.05),but the number was de-creased with Ahr antagonist intervention ( 5.80 ±0.83 , P<0.05 ) .Conclusion The number of activated Th17 cells was increased in MLNs and peripheral blood samples from mice with IBS .Ahr played an important role in the activation of Th17 cells in intestines.However,the number of Ahr-activated Th17 cells in intestinal mucosa and the proportion of Th 17 cells in MLNs could be down-regulated through blocking Ahr .

Effects of Bifidobacterium infantis on intestinal corticotropin releasing factor receptors and mast cells activation in a murine model of irritable bowel syndrome / 中华微生物学和免疫学杂志

Objective To investigate the effects of Bifidobacterium infatn ison the expression of in -testinal corticotropin releasing factor ( CRF) receptors and how the peripheral CRF receptors activate mast cells in a murine model of irritable bowel syndrome (IBS).Methods Thirty BALB/c male mice were ran-domly divided into three groups including control group , model group and Bifidobacterium infantis group. The mouse model of IBS was established by using chronic restraint stress .Mice in Bifidobacterium infantis group received daily intragastrical administration of Bifidobacterium infantis for 14 days.Mice in control and model groups were treated with equal volume of saline .Then all mice were killed after the assessment of weight and abdominal withdrawal reflex ( AWR) .The levels of histamine , tryptase and tumor necrosis fac-tor-α( TNF-α) in serum samples were detected by ELISA .The expression of CRF in colonic mucosa was analyzed by immunohistochemistry .The expression of CRF-R1 and CRF-R2 in mast cells and the number of mast cells in colonic mucosa were detected by double immunofluorescence staining assay .The expression of CRF-R1 and CRF-R2 at mRNA level in colon were detected by reverse transcription polymerase chain reac-tion ( RT-PCR) .Results Compared with control group , the levels of histamine , tryptase and TNF-αin pe-ripheral blood samples , the expression of CRF-R1 and CRF-R2 at mRNA level , and the number of mast cells, CRF-R1+mast cells and CRF-R2+mast cells in colonic mucosa were increased significantly in model group (P<0.05), but were remarkably down-regulated with the treatment ofB ifidobacterium infantis (P<0.05).Conclusion Bifidobacterium infantis could reduce the activation of mast cells in a murine model of IBS by inhibiting the expression of CRF-R1 and CRF-R2 in intestinal mast cells .

Effects of Clostridium butyricum combined with glutamine on the expression of intestinal tight junction protein in stress mouse model / 中华消化杂志

Objective To investigate the mechanism of the permeability of intestinal mucosa in the pathogenesis of irritable bowel syndrome (IBS) and the interventional effects of Clostridium butyricum combined with glutamine.Methods According to random number method,fifty BALB/c mice were divided into control group,experimental control group,glutamine group,Clostridium butyricum group and combination group.IBS mice model was established by water-avoidance stress (WAS) experiment.The defecating time of mice and fecal water content were detected by dyed stool after mice gavaged with methylcellulose (1.5％).The pathological injury of intestine was assessed by hematoxylin and eosin staining.The visceral sensitivity was evaluated by colorectal distention test (CRD).The changes of the permeability of intestine was evaluated by detecting the changes of serum D-lactic acid (D-LA),level of diamine oxidase (DAO),expressions of intestinal epithelial cells (IEC) cell tight junction protein (TJ) (occludin-1,claudin-1,zonula occludens-1 (ZOL-1)) at protein level.The interventional effects of Clostridium butyricum combined with glutamine were evaluated.t test was performed for comparison between groups,and analysis of variance was used for comparison among multi-groups.Results Compared with the control group,the defecating time of experimental control group was significantly shorten ((100.40±14.80) min vs (75.88±12.20) min and water content of fecal significantly increased ((54.76±9.98)％ vs (74.95±7.15)％,t =3.692 and 4.023; P=0.002 and 0.002).The lowest threshold of visceral sensitivity significantly decreased ((40.87 ± 4.82) mmHg (1 mmHg=0.133 kPa) vs (27.80±3.18) mmHg; t=8.761,P＜0.01),while the mucosal pathological injury score significantly increased (0.50±0.15 vs2.60±0.97; t＝6.034,P＜0.01).The level of D-LA ((1 476±246.8) ng/L vs (913.6±90.1) ng/L)) and DAO ((3 391.0±256.9) vs (5 096.0±725.2) ng/L) significantly increased (t=40.920 and 29.810; both P＜0.05),and the expression of tight junction protein ZOL-1 (0.165±0.005 vs0.119±0.003),occludin-1 (0.104±0.016 vs 0.022±0.006) significantly decreased (t=19.830 and 19.830; both P＜0.01).Compared with the experimental control group,after intragastric intervention the defecating time of glutamine group,Clostridium butyricum group and combination group increased ((90.50±3.78),(97.56±8.79) and (99.89±11.90) min and water content of fecal decreased ((69.33±6.71)％,(58.07±8.97)％ and (56.74±8.12)％) and the differences were statistically significant (F=10.020 and 8.740; both P＜0.01).The results of Clostridium butyricum group and combination group were good (F=2.481 and 4.874; both P＜0.05).And the lowest threshold of visceral sensitivity significantly increased ((31.80±2.69),(36.04±5.06) and (38.93±3.30) mmHg; F=2.420,P＜0.05),the result of combination group was the best (F=3.550,P＜0.01).Jejunal mucosal injury was significantly reduced (2.00 ± 0.94,1.30 ± 0.68 and 1.30±0.48; F＝11.350,P＜0.01).After intragastric intervention,serum levels of D-LA ((1 370.0± 78.9),(1 066.0±155.5) and (1 039.0±129.0) ng/L) and DAO ((4 808.0±477.4),(3 713.0± 595.0) and (3 725.0±615.9) ng/L) of glutamine group,Clostridium butyricum group and combination group significantly decreased (F＝37.480 and 27.670; both P＜0.01).The level of ZOL-1(0.126± 0.014,0.125±0.006,0.138±0.004) and occludin 1 (0.037±0.013,0.073±0.028,0.078±0.027) of glutamine group,Clostridium butyricum group and combination group significantly increased,and the differences were statistically significant (F=5.867 and 10.630; both P＜0.05).The change of ZOL-1 of combination group was more than that of Clostridium butyricum group (t =5.457,P ＜ 0.05).Conclusions WAS experiment can induce visceral hypersensitivity,increase the permeability of intestine and reduce the function of intestinal epithelial barrier.Clostridium butyricum and glutamine are effective in the recovery of visceral hypersensitivity and the permeability of mucosal epithelia cells.

Pathogenic effect of intestinal immune dysfunction on irritable bowel syndrome in mouse model / 中华微生物学和免疫学杂志

Objective To investigate the role of intestinal immune dysfunction in the pathogenesis of irritable bowel syndrome(IBS) and to study the effects of Clostridium butylicum on the regulation of intestinal immune disorders.Methods A total of 50 male 6-week-old C57BL/6 mice were randomly divided into three groups,including the experimental group (n =20),the control group (n =20) and the Clostridium butylicum group(n =10).A mouse model of constipation-predominant IBS (C-IBS) was established by perfusing sodium butyrate solution(200 μl,concentration of 500 mmol/L) into the mouse colon twice a day for three consecutive days.The mice in control group were intrarectally perfused with normal saline enema (200 μl).Two hours before the perfusion of sodium butyrate into colon,the mice in Clostridium butylicum group were given Clostridium butylicum 500 μl(viable cell concentration of 1×109 CFU/ml) by oral gavage once a day for six days.The colorectal distention test(CRD) was carried out for evaluation of clinical parameters.HE staining of intestinal tissue section was performed for histopathological assessment of colonic mucosal inflammation.Intestinal intraepithelial lymphocytes (IELs) and lamina propria mononuclear cells (LPMCs) were isolated and analyzed by flow cytometry to evaluate the correlation between IBS and intestinal immune dysfunction/abnormal activation of intestinal immune cells in mouse model of C-IBS,and to assess the regulatory effects of Clostridium butylicum on the intestinal immune disorder.Results (1) Compared with the control group,the mice in experimental group showed a significant change in physiological parameters,histological structure of colon,inflammatory cells infiltration and low-grade inflammatory state.There was a significant increase in scores of CRD and a decrease in lowest sensory threshold (t=8.926 and t=6.103,both P＜0.001) ; (2) There was a decrease in the numbers of DC in IELs (t =2.878 and t =3.086,both P＜0.05),but an increase in the numbers of macrophage (t=3.191,P＜0.05) and the memory T cells in mice with IBS (t=3.071,P＜0.05) as compared with that in control group; (3)DCs were decreased (t=2.880 and t=2.664,both P＜0.05),but memory T cells were increased (t =3.732 and 2.682,P＜0.01 and P＜0.05) in the LPMCs of mice in experimental group; (4)There was no significant difference in the physiological index between the mice in control group and the Clostridium butylicum group.Levels of memory T cells,macrophages and DCs in the IELs were close to the normal level (6 d,t =1.103,0.0213,0.418,all P＞0.05),and levels of macrophages and DCs in the LPMCs of mice in the Clostridium butylicum group were also similar to that in the control group (6 d,t =0.782,0.347,both P＞0.05) ; (5) Compared with the mice in experimental group,the level of memory T cells in LPMCs of mice treated with Clostridium butylicum was dramatically declined (6 d,t=2.346,P=0.0470,P＜0.05),however,which was still higher than that of mice in control group (6 d,t =2.233,P =0.0476,P＜0.05).The intestinal immune function was restored to normal level with Clostridium butylicum intervention.Conclusion The pathophysiologic mechanism of IBS might be closely related to the abnormal activation of intestinal immune cellsand disordered functional state in the intestinal mucosa.Clostridium butylicum could regulate the intestinal immune homeostasis and restore the physiological function of gastrointestinal tract.

Effects of corticotrophin-releasing factor on the Toll-like receptor 4/nuclear factor-rB signaling pathway in human intestinal epithelial cell line HT-29 / 中华消化杂志

Objective To investigate the effect of corticotrophin-releasing factor (CRF) on the regulation of Toll-like receptor 4/NF-κB signaling pathway expression in human intestinal epithelial cell line HT-29. Methods HT-29 cells were divided into four groups, normal control group, LPS group (LPS 20 μg/ml stimulated for 24 h), CRF group (CRF 20 ng/ml stimulated 24 h) and CRF+ LPS group (CRF incubated for 12 h then changed to LPS for another 12 h). After stimulation, the expression of TLR4 mRNA of each group was examined by reverse transcriptase polymerase chain reaction (RT-PCR). Total cell protein were extracted and the expression of TLR4 and NFκB p65 at protein level were detected by western blotting.Cell culture supernatant was collected and the secretion of interleukin-8 was detected by enzyme-linked immunoasorbent assay (ELISA). Results The expression of TLR4 in LPS group at mRNA and protein level were 0.31±0.04 and 0.48±0.17,there was no significant difference compared with normal control group (0.28±0.02 and 0.45±0.12,t＝0.216 and 0.712 , P＞0.05 ). In CRF group which were 1.05±0.06 and1. 08±0.21, significantly higher than normal control group (t＝3.721 and 3.802, P＜0.05). In CRF+LPS group which were 1.68±0.05 and 1.81±0. 18,significantly higher than CRF group (t＝4. 816 and 3. 918, P＜0.05).The results of NF-κB p65 expression at protein level and interleukin-8 expression of cell culture supernatant were consistent with the results of TLR4 expression at mRNA and protein level.Conclusion CRF not only activate TLR4/NF-κB signaling pathway in human intestinal epithelial cell,but enhance the reaction of intestinal epithelial cell to LPS as well, which resulting in increased interleukin-8 secretion.

No influence of Lewis B expression in Helicobacter pylori on bacterial adhesion property / 中华消化杂志

Objective To investigate the possible influence of Lewis B expression in Helicobacter pylori (H.pylori) on bacterial adhesion property, and determine the relationship between babA 2 gene in H.pylori and peptic ulcer. Methods The bacterial adhesion property in a total of 78 H.pylori strains was performed using adherence assay in vitro, and the frequency of babA 2 gene was determined by polymerase chain reaction (PCR). Results Among 47 H.pylori strains isolated from peptic ulcer patients, 18 (38.3%) were positive for babA 2 gene, while babA 2 was positive in 14 (45.2%) of 31 strains isolated from non ulcer dyspepsia patients ( P =0.427). Among 31 H.pylori strains expressing Lewis B, 24 (77.4%) were positive for adherence assay, compared with 38 (80.9%) of 47 H.pylori strains without expression of Lewis B ( P =0.463). Conclusions (1) There is no association between babA 2 status in H.pylori strain and peptic ulcer in our population; (2) The expression of Lewis B in H.pylori does not interfere with bacterial adhesion property, and thus supports that the gastric epithelium is the receptor for Lewis B of H.pylori.