Protective effects of Baicalin injection on severe acute pancreatitis through regulating follistatin-like-1 signaling pathway by down-regulating miR-429 expression in mice

Abstract In China, Scutellaria is used for treating inflammatory-related diseases. Baicalin is the main active component of Scutellaria and has protective effects on acute pancreatitis. However, the mechanism of Baicalin is still unclear. In this study, the protective effects of baicalin on acute pancreatitis induced by taurocholate and its mechanism are investigated. In this study, mice were randomly divided into three groups: sham operation, model, and treatment groups. Acute pancreatitis in mice was induced by intraperitoneal injection of taurocholate (35 mg/kg). The treatment group was given baicalin (100 mg/kg) 2 h before acute pancreatitis induction. The mRNA expression levels of miR-429, nuclear factor kappa B65(NF-kB65), toll-like receptor 4(TLR4), TNF receptor associated factor6 (TRAF6), NF-kappa-B inhibitor(IkB), Follistatin-like 1 (FSTL1), and interleukin-1 receptor-associated kinase (IRAK) in the liver tissues 24 h after intraperitoneal injection were detected by RT-PCR. Then, the expression levels of NF-kB65, p-NF-κB65, TLR4, TRAF6, IkB, FSTL1, IRAK, p- IRAK, and p- IkB-а proteins were detected by Western blot. IL-6, TNF-α and IL-1 ß in plasma were measured by ELISA, and histopathological changes in the pancreases of the mice were observed. The results showed that after baicalin treatment, miR-429 expression in the pancreatic tissues and the expression levels of NF-kB65, TLR4, TRAF6, p-IkB-а, FSTL1, and p-IRAK decreased. Similarly, pancreatic myeloperoxidase (MPO) activity and the plasma levels of IL-6, TNF-а, IL-12, IL-1ß1, endotoxin, serum amylase, and lipase were reduced. Thus, the pancreatic injury induced by taurocholate was alleviated. The present study indicates that pretreatment with Baicalin can alleviate acute pancreatic injury induced by taurocholate in mice. The mechanism may be associated with the decreased miR-429 expression, reduced FSTL1 signaling pathway activity, TLR4 and TLR4/MyD88 signaling pathway inhibition, and reduced pancreatic inflammation. FSTL1 is the regulatory target for miR-429

Development of Advanced Atherosclerotic Plaque by Injection of Inflammatory Proteins in a Rabbit Iliac Artery Model

PURPOSE: Appropriate animal models of atherosclerotic plaque are crucial to investigating the pathophysiology of atherosclerosis, as well as for the evaluation of the efficacy and safety of vascular devices. We aimed to develop a novel animal model that would be suitable for the study of advanced atherosclerotic lesions in vivo. MATERIALS AND METHODS: Atherosclerotic plaque was induced in 24 iliac arteries from 12 rabbits by combining a high cholesterol diet, endothelial denudation, and injection into the vessel wall with either saline (n=5), olive oil (n=6), or inflammatory proteins [n=13, high-mobility group protein B1 (HMGB1) n=8 and tumor necrosis factor (TNF)-α n=5] using a Cricket™ Micro-infusion catheter. Optical coherence tomography (OCT) was performed to detect plaque characteristics after 4 weeks, and all tissues were harvested for histological evaluation. RESULTS: Advanced plaque was more frequently observed in the group injected with inflammatory proteins. Macrophage infiltration was present to a higher degree in the HMGB1 and TNF-α groups, compared to the oil or saline group (82.1±5.1% and 94.6±2.2% compared to 49.6±14.0% and 46.5±9.6%, p-value<0.001), using RAM11 antibody staining. On OCT, lipid rich plaques were more frequently detected in the inflammatory protein group [saline group: 2/5 (40%), oil group: 3/5 (50%), HMGB1 group: 6/8 (75%), and TNF-α group: 5/5 (100%)]. CONCLUSION: These data indicate that this rabbit model of atherosclerotic lesion formation via direct injection of pro-inflammatory proteins into the vessel wall is useful for in vivo studies investigating atherosclerosis.