Octreotide ameliorates intestinal dysmotility by interstitial cells of Cajal protection in a rat acute necrotizing pancreatitis model

Intestinal Mucosal Immune Barrier: A Powerful Firewall Against Severe Acute Pancreatitis-Associated Acute Lung Injury via the Gut-Lung Axis

The pathogenesis of severe acute pancreatitis-associated acute lung injury (SAP-ALI), which is the leading cause of mortality among hospitalized patients in the intensive care unit, remains incompletely elucidated. The intestinal mucosal immune barrier is a crucial component of the intestinal epithelial barrier, and its aberrant activation contributes to the induction of sustained pro-inflammatory immune responses, paradoxical intercellular communication, and bacterial translocation. In this review, we firstly provide a comprehensive overview of the composition of the intestinal mucosal immune barrier and its pivotal roles in the pathogenesis of SAP-ALI. Secondly, the mechanisms of its crosstalk with gut microbiota, which is called gut-lung axis, and its effect on SAP-ALI were summarized. Finally, a number of drugs that could enhance the intestinal mucosal immune barrier and exhibit potential anti-SAP-ALI activities were presented, including probiotics, glutamine, enteral nutrition, and traditional Chinese medicine (TCM). The aim is to offer a theoretical framework based on the perspective of the intestinal mucosal immune barrier to protect against SAP-ALI.

Gut microbiota interacts with inflammatory responses in acute pancreatitis

Acute pancreatitis (AP) is one of the most common acute abdominal conditions, and its incidence has been increasing for years. Approximately 15-20% of patients develop severe AP (SAP), which is complicated by critical inflammatory injury and intestinal dysfunction. AP-associated inflammation can lead to the gut barrier and function damage, causing dysbacteriosis and facilitating intestinal microbiota migration. Pancreatic exocrine deficiency and decreased levels of antimicrobial peptides in AP can also lead to abnormal growth of intestinal bacteria. Meanwhile, intestinal microbiota migration influences the pancreatic microenvironment and affects the severity of AP, which, in turn, exacerbates the systemic inflammatory response. Thus, the interaction between the gut microbiota (GM) and the inflammatory response may be a key pathogenic feature of SAP. Treating either of these factors or breaking their interaction may offer some benefits for SAP treatment. In this review, we discuss the mechanisms of interaction of the GM and inflammation in AP and factors that can deteriorate or even cure both, including some traditional Chinese medicine treatments, to provide new methods for studying AP pathogenesis and developing therapies.

Application of nanotechnology in the diagnosis and treatment of acute pancreatitis

Acute pancreatitis (AP) is a common digestive system disease. The severity of AP ranges from mild edema in the pancreas to severe systemic inflammatory responses leading to peripancreatic/pancreatic necrosis, multi-organ failure and death. Improving the sensitivity of AP diagnosis and developing alternatives to traditional methods to treat AP have gained the attention of researchers. With the continuous rise of nanotechnology, it is being widely used in daily life, biomedicine, chemical energy and many other fields. Studies have demonstrated the effectiveness of nanotechnology in the diagnosis and treatment of AP. Nanotechnology has the advantages of simplicity, rapidity and sensitivity in detecting biomarkers of AP, as well as enhancing imaging, which helps in the early diagnosis of AP. On the other hand, nanoparticles (NPs) have oxidative stress inhibiting and anti-inflammatory effects, and can also be loaded with drugs as well as being used in anti-infection therapy, providing a new approach for the treatment of AP. In this article, we elaborate and summarize on the potential of nanoparticles for diagnostic and therapeutic applications in AP from the current reported literature and experimental results to provide useful guidelines for further research on the application of nanotechnology.

Bacterial translocation in acute pancreatitis

Bacterial translocation is a phenomenon in which live bacteria or their products cross the intestinal barrier to other organs or the circulatory system. Gut translocation of bacteria has been reported in both animal models, and clinical trials often accompany acute pancreatitis and are believed to be linked to patient outcome, especially in severe acute pancreatitis. Therefore, the mechanisms of intestinal bacterial translocation in acute pancreatitis have become a topic of interest in recent years. This review discusses Bacterial translocation in acute pancreatitis, identifies possible mechanisms of action, and provides an overview of the methods used to detect Bacterial translocation in acute pancreatitis. This review also highlights areas that require further research.

Autophagy Strengthens Intestinal Mucosal Barrier by Attenuating Oxidative Stress in Severe Acute Pancreatitis

BACKGROUND

Intestinal mucosal barrier dysfunction can be caused by severe acute pancreatitis (SAP). It is normally associated with changes to mucosal autophagy and oxidative stress.

OBJECTIVE

The aim of this study was to investigate the correlation between autophagy and oxidative stress on the intestinal mucosal barrier of SAP rat model.

METHODS

SAP was induced by retrograde injection of sodium taurocholate (5%) into the biliopancreatic duct. Bacterial translocation (BT) was detected by 16S rDNA sequencing analysis. Morphological alterations in the pancreas and gut were determined by hematoxylin-eosin staining. Oxidative stress status was determined by measuring the level of intestinal malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GPx). Western blot, RT-PCR, and immunofluorescent staining were preformed to analyze the expression of tight junction and autophagy proteins.

RESULTS

According to the sequencing analysis, rats in SAP group were divided into BT (+) group (n = 9) and BT (-) group (n = 8). Pancreatic and intestinal injuries in SAP group were significantly higher than sham operation group. The content of MDA was clearly elevated, and SOD as well as GPx activities were decreased in BT (+) group as compared with BT (-) group. The expression of LC3II and Beclin1 in BT (-) group was higher than that observed in BT (+). In contrast, BT (+) group had a higher level of claudin-2 and a lower level of zonula occluden-1, occludin, and claudin-1.

CONCLUSION

These results suggest that activated autophagy may attenuate intestinal mucosal barrier dysfunction by preventing and reducing the oxidative stress in SAP.

Sham Feeding with Chewing Gum in Early Stage of Acute Pancreatitis: A Randomized Clinical Trial

Background

The correlation between sham feeding and acute pancreatitis (AP) has only been examined in limited studies. We aimed to investigate the efficacy and safety of sham feeding in the early stage of AP.

Material/Methods

A randomized controlled clinical trial was performed. Equal groups of AP patients were recruited. Patients in the sham feeding group received chewing gum 4 times a day after admission. All patients in the trial received standard treatment consistent with the guidelines for AP. The primary outcomes were mortality, length of stay (LOS), and medical expenses. Secondary outcomes were the incidence of complications and other adverse events, return of gastrointestinal function, the details of enteral nutrition and intra-abdominal pressure.

Results

From May 2014 to December 2015, a total of 204 patients were recruited. The LOS and hospital costs in the sham feeding group were reduced, although mortality was equivalent between groups. The return of gastrointestinal function occurred earlier in the sham feeding group, with no complications related to gum chewing.

Conclusions

Sham feeding with chewing gum is safe and efficacious in the early stage of AP.

Effect of da-cheng-qi decoction on the repair of the injured enteric nerve-interstitial cells of cajal-smooth muscle cells network in multiple organ dysfunction syndrome

Wistar rats were randomly divided into control group, multiple organ dysfunction syndrome (MODS) group, and Da-Cheng-Qi decoction (DCQD) group. The network of enteric nerves-interstitial cells of Cajal- (ICC-) smooth muscle cells (SMC) in small intestine was observed using confocal laser scanning microscopy and transmission electron microscopy. The results showed that the numbers of cholinergic/nitriergic nerves, and the deep muscular plexus of ICC (ICC-DMP) and connexin43 (Cx43) in small intestine with MODS were significantly decreased. The network integrity of enteric nerves-ICC-SMC was disrupted. The ultrastructures of ICC-DMP, enteric nerves, and SMC were severely damaged. After treatment with DCQD, the damages were repaired and the network integrity of enteric nerves ICC-SMC was significantly recovered. In conclusion, the pathogenesis of gastrointestinal motility dysfunction in MODS in part may be due to the damages to enteric nerves-ICC-SMC network and gap junctions. The therapeutic mechanism of DCQD in part may be that it could repair the damages and maintain the integrity of enteric nerves ICC-SMC network.

Recent advances in the investigation of pancreatic inflammation induced by large doses of basic amino acids in rodents

It has been known for approximately 30 years that large doses of the semi-essential basic amino acid L-arginine induce severe pancreatic inflammation in rats. Recently, it has been demonstrated that L-arginine can also induce pancreatitis in mice. Moreover, other basic amino acids like L-ornithine and L-lysine can cause exocrine pancreatic damage without affecting the endocrine parenchyma and the ducts in rats. The utilization of these noninvasive severe basic amino acid-induced pancreatitis models is becoming increasingly popular and appreciated as these models nicely reproduce most laboratory and morphological features of human pancreatitis. Consequently, the investigation of basic amino acid-induced pancreatitis may offer us a better understanding of the pathogenesis and possible treatment options of the human disease.

Prediction of octreotide efficacy by electrogastrography in the treatment of patients with esophageal variceal hemorrhage

Our aim is to investigate the significance of electrogastrography in the treatment of esophageal variceal hemorrhage with octreotide. Electrogastrography was performed in patients with esophageal variceal hemorrhage before and during the treatment consisting of various doses of octreotide (25 ug h(-1) group and 50 ug h(-1) group). The dominant power of electrogastrography and its relationship with the hemostatic efficacy of octreotide treatment were evaluated. Dominant power of electrogastrography decreased significantly during treatment with octreotide (P < 0.05). The reduction in the amplitude of dominant power in the 50 ug h(-1) group was significantly larger than in the 25 ug h(-1) group (P < 0.05), and it was correlated with hemostatic efficacy of octreotide treatment. We conclude that octreotide treatment in patients with esophageal variceal hemorrhage can result in a significant decrease of dominant power, which correlates with the hemostatic efficacy of octreotide, so the change of dominant power could be used as a predictor of evaluating the treatment efficacy of octreotide in esophageal variceal hemorrhage patients.

Effect of octreotide on enteric motor neurons in experimental acute necrotizing pancreatitis

Background/Aims

Amelioration of intestinal dysmotility and stasis during the early period of acute necrotizing pancreatitis (ANP) appears to be important to reduce the risks of secondary pancreatic infection. We aimed to characterize the association between the neuropathy of the enteric nervous system and gut dysfunction and to examine the effect of octreotide on motor innervation in the early stage of ANP.

Methodology/Principal Findings

The rats were randomly divided into eight groups: control+saline; control+octreotide; ANP+saline and ANP+octreotide (24 h, 48 h, 72 h). The spontaneous activity of ileal segments and the response to ACh, l-NNA were recorded. The alterations of myenteric neuronal nitric oxide synthase (nNOS), choline acetyltransferase (CHAT), PGP9.5 and somatostatin receptor 2 (SSTR₂) immunoreactive cells were evaluated by immunofluorescence and the protein expression of nNOS and CHAT were evaluated by western blot. We found the amplitude of spontaneous contractions at 48 h and the response to ACh at 24 h declined in the ANP+saline rats. A higher contractile response to both ACh and to l-NNA was observed in the ANP+octreotide group, compared with the ANP+saline rats at 24 h. A significant reduction in the nNOS and cholinergic neurons was observed in ANP+saline rats at the three time points. However, this reduction was greatly ameliorated in the presence of octreotide at 24 h and 48 h. The protein expression of CHAT neurons at 24 h and the nNOS neurons at 48 h in the ANP+octreotide rats was much higher than the ANP+saline rats.

Conclusion

The pathogenesis of ileus in the early stage of ANP may be related to the neuropathy of the enteric nervous system. Octreotide may reduce the severity of ileus by lessening the damage to enteric motor innervation.