Inhibition of angiotensin II type 1 receptor reduces oxidative stress damage to the intestinal barrier in severe acute pancreatitis.

Intestinal barrier injury is a common complication of severe acute pancreatitis (SAP), which is often accompanied by intestinal mucosal barrier injury and results in serious consequences. However, the exact mechanism remains unclear. We aimed to investigate whether angiotensin II type 1 receptor (AT1)-mediated oxidative stress is involved in SAP intestinal barrier injury and assessed the effects of inhibiting this pathway. The SAP model was established by retrograde bile duct injection of sodium taurocholate (5%). The rats were divided into three groups: the control group (SO), the SAP group (SAP), and the azilsartan intervention group (SAP + AZL). Serum amylase, lipase, and other indexes were measured to evaluate SAP severity in each group. Histopathological changes in the pancreas and intestine were evaluated by HE staining. The oxidative stress of intestinal epithelial cells was detected by superoxide dismutase and glutathione. We also detected the expression and distribution of intestinal barrier-related proteins. The results showed that the serum indexes, the severity of tissue damage, and the level of oxidative stress in the SAP + AZL group were significantly lower than in the SAP group. Our study provided hitherto undocumented evidence of AT1 expression in the intestinal mucosa, confirming that AT1-mediated oxidative stress is involved in SAP intestinal mucosal injury, and inhibiting this pathway could effectively reduce intestinal mucosal oxidative stress injury, providing a new and effective target for the treatment of SAP intestinal barrier injury.

[Effects of Fritillariae Cirrhosae Bulbus on MMP-2,MMP-9 and TIMP-1 in murine asthma model].

To investigate the effects of Fritillariae Cirrhosae Bulbus on airway remodeling and matrix metalloproteinase-2(MMP-2), matrix metalloproteinase-9(MMP-9), tissue inhibitor-1 of metalloproteinase(TIMP-1) of a murine asthma model, and explore its mechanism in treatment of asthma. BALB/C murines were randomly divided into the normal group, model group, high dose group, low dose group, and positive control group. Except for the normal group, all the other groups received ovalbumin(OVA) to establish murine asthma model. After successful modeling, the murines in high dose group and low dose group were orally administered with Fritillariae Cirrhosae Bulbus powder at the dose of 18.0 mg•kg⁻¹ and 9.0 mg•kg⁻¹, respectively; the murines in positive control group were injected intraperitoneally with dexamethasone at the dose of 0.5 mg•kg⁻¹; while the murines in normal group and the model group were orally administered with the same volume of normal saline. All the drugs were given to murines per day for 28 d. The variations of airway responsiveness, variations of the total cell count and leukocyte differential count in bronchoalveolar lavage fluid(BALF), and the variations of thicknesses of bronchial wall and airway smooth muscle of each group were observed. The levels of MMP-2, MMP-9 and TIMP-1 were measured by ELISA; and the expression levels of MMP-2, MMP-9 and TIMP-1 mRNA were detected by RT-PCR. The results showed that as compared with the normal group, the airway responsiveness, the count of total cells, neutrophils, macrophage, lymphocytes, eosinophils in BALF, and the thicknesses of bronchial wall and airway smooth muscle were increased significantly in the model group(P<0.01); as compared with the model group, the above indicators were decreased significantly in the high dose group, low dose group and positive control group (P<0.05 or P<0.01). As compared with the normal group, the levels and expressions of MMP-2, MMP-9 and TIMP-1 mRNA were increased significantly in the model group(P<0.01); while as compared with the model group, these levels were decreased significantly in the high dose group, low dose group and positive control group(P<0.01). In conclusion, Fritillariae Cirrhosae Bulbus can improve airway remodeling in a murine asthma model, and its mechanisms may be related to down-regulating MMP-2, MMP-9 and TIMP-1 levels.

Research progress on the relationship between zinc deficiency, related microRNAs, and esophageal carcinoma.

Esophageal cancer (EC) is a common malignant tumor of the gastrointestinal tract with a high incidence in China. Zinc (Zn) deficiency is a key risk factor for the occurrence and development of EC and affects progression by regulating microRNA (miRNA, miR) expression. In addition, the dysregulation of miRNAs is accompanied by the dysregulation of their target genes in EC. In this paper, we review the potential molecular mechanisms between Zn deficiency and EC with the aim of providing new strategies and methods for early diagnosis, targeted therapy, and prognostic evaluation.

Association between circulating microRNA-208a and severity of coronary heart disease.

Circulating microRNA (miR)-208a is specifically expressed in the heart muscle, which is involved in the regulation of myosin during cardiac development. Previous studies reported that cardiac-specific miR-208a level is significantly higher in plasma of coronary heart disease (CHD) patients. However, whether it correlates with severity of CHD, has never been elucidated before. The aim of this study was to explore the association between miR-208a and the presence and severity of CHD. Samples were collected from 290 CHD patients and 110 subjects with angiographic exclusion of CHD. Circulating miRNA-208a expression was detected using quantitative real-time PCR. The Gensini score was used to evaluate the severity of coronary stenotic lesions. Expression of miRNA-208a was identified on the basis of the quartiles of the Gensini score, and association between the miRNA-208a levels and CHD was analyzed. Diagnostic potential of miR-208a of CHD was performed by ROC analysis. CHD patients had higher miRNA-208a expression (1.61, 0.45-3.86 vs. 0.66, 0.11-1.42, p < .001), and the biomarker level significantly increased following an increasing the Gensini score (p < .001). Gensini score was significantly associated with miRNA-208a expression (r = 0.8525, p < .001). The optimal cut-off value of the relative level of miR-208a was with a specificity of 93.6% and a sensitivity of 75.5%. The AUC of miR-208a was 0.919 (95% CI, 0.893-0.945; p < .001). These preliminary results suggest that the expression of miR-208a may be associated with atherogenesis. The level of circulating miR-208a in predicting the severity of coronary atherosclerosis may have a relatively certain value.