Somatostatin and somatostatin analogues--are they indicated in the management of acute pancreatitis?

Octreotide attenuates intestinal barrier damage by maintaining basal autophagy in Caco2 cells

The intestinal mucosal barrier is of great importance for maintaining the stability of the internal environment, which is closely related to the occurrence and development of intestinal inflammation. Octreotide (OCT) has potential applicable clinical value for treating intestinal injury according to previous studies, but the underlying molecular mechanisms have remained elusive. This article is based on a cell model of inflammation induced by lipopolysaccharide (LPS), aiming to explore the effects of OCT in protecting intestinal mucosal barrier function. A Cell Counting Kit‑8 assay was used to determine cell viability and evaluate the effectiveness of OCT. Gene silencing technology was used to reveal the mediated effect of somatostatin receptor 2 (SSTR2). The changes in intestinal permeability were detected through trans‑epithelial electrical resistance and fluorescein isothiocyanate‑dextran 4 experiments, and the alterations in tight junction proteins were detected using immunoblotting and reverse transcription fluorescence‑quantitative PCR technology. Autophagosomes were observed by electron microscopy and the dynamic changes of the autophagy process were characterized by light chain (LC)3‑II/LC3‑I conversion and autophagic flow. The results indicated that SSTR2‑dependent OCT can prevent the decrease in cell activity. After LPS treatment, the permeability of monolayer cells decreased and intercellular tight junctions were disrupted, resulting in a decrease in tight junction protein zona occludens 1 in cells. The level of autophagy‑related protein LC3 was altered to varying degrees at different times. These abnormal changes gradually returned to normal levels after the combined application of LPS and SSTR2‑dependent OCT, confirming the role of OCT in protecting intestinal barrier function. These experimental results suggest that OCT maintains basal autophagy and cell activity mediated by SSTR2 in intestinal epithelial cells, thereby preventing the intestinal barrier dysfunction in inflammation injury.

Emerging Therapies to Prevent Post-ERCP Pancreatitis

PURPOSE OF REVIEW

The aim of this review is to evaluate emerging, novel therapies for the prevention of post-ERCP pancreatitis.

RECENT FINDINGS

Rectal indomethacin reduces the risk of pancreatitis in low- and average-risk patients, who comprise the majority of patients undergoing ERCP. An 8-h protocol of aggressive lactated Ringer's reduces the risk of pancreatitis in average-risk patients. Sublingual nitrate may provide additional benefit to rectal NSAIDs in preventing PEP. A tacrolimus trough > 2.5 ng/mL was recently shown to be associated with a lower risk of PEP in liver transplant patients undergoing ERCP. Routine usage of rectal indomethacin in all patients undergoing ERCP reduces the risk of PEP. Pancreatic-duct stents reduce the risk of PEP in high-risk patients. There is emerging data that aggressive hydration with lactated Ringer's and nitrates may further reduce PEP. Tacrolimus is a promising potential agent to prevent PEP but needs further clinical study.

Historical review of our knowledge of acute pancreatitis

Acute pancreatitis is one of most common causes of consultation due to abdominal pain in medical emergency units and it requires hospital admission. Although the majority of cases are mild and patients tend to recover quickly, a small percentage of cases is severe, with mortality in the region of 5-10%. This historical review considers how our understanding of this disease has changed since it was first described in 1579 thanks to the contributions of renowned experts such as Nicolaes Tulp, Reginald Fitz, Nicholas Senn and many others who, through their expertise and dedication, have improved the survival of patients with this disease.

Metabolic complications of endocrine surgery in companion animals

Metabolic complications of endocrine surgery occur commonly and precautions should be taken to avoid potentially life-threatening situations and to lessen expense associated with a more extended hospital stay. Common complications of endocrine surgery as well as prevention strategies will be reviewed for pancreatic, parathyroid, and adrenal surgery.

Effects of gabexate mesilate (FOY) on amylase and phospholipase A2 in human serum and pancreatic juice

The precise inhibitory action of gabexate mesilate (GM) on the various pancreatic enzymes remains unclear. We designed this study to investigate the enzyme inhibitory action of GM in the serum and directly in the pancreatic juice. We observed 16 cases with postoperative pancreatic drainage. Patients were randomly assigned to one of two groups, to receive GM at a dose of 600 mg/24 hr (treated group: 8 patients) or a physiological solution (control group: 8 patients) by continuous intravenous infusion. In both groups pancreatic juice and serum were sampled three times: before infusion began (T0) and at 12 hr (T1) and 24 hr after infusion ended (T2). At the end of the study, seven patients received octreotide and the volume of pancreatic secretion was determined. No statistical difference was observed in serum amylase and phospholipase A2 activity in the treated and control groups. On the contrary, amylase and phospholipase A2 activity in the pancreatic juice diminished significantly only in the treated group, and in these patients a GM metabolite was also detectable in the pancreatic secretion. The volume of pancreatic secretion decreased only after infusion of octreotide. The enzyme inhibition in the pancreatic gland itself and the central role of inhibition of phospholipase A2 in the enzyme cascade responsible for activating other proteases, confirm the therapeutic use of GM in acute pancreatitis. An association of GM and octreotide during acute pancreatitis should be useful because of their different mechanisms.

Stimulated gastrointestinal hormone release and gallbladder contraction during continuous jejunal feeding in patients with pancreatic pseudocyst is inhibited by octreotide

BACKGROUND

Continuous enteral feeding, the old-new therapeutic modality in the treatment of patients with acute pancreatitis and those with complications is considered to bypass the cephalic, the gastric, and (at least in part) the intestinal phase of pancreatic secretion. The aim of this study was to test the GI hormonal changes and gallbladder motility during CJF in patients with pancreatic pseudocysts following acute pancreatitis, with or without octreotide pretreatment.

PATIENTS AND METHODS

In 15 patients with pancreatic pseudocysts, an 8-French (8F) nasojejunal catheter was positioned into the jejunum distal to the ligament of Treitz during duodenoscopy. On test d 1, blood samples were taken for CCK, gastrin, insulin-like immunoreactivity (IRI), glucagon, and glucose measurements prior to and at 20, 40, 60, and 120 min following jejunal saline infusion at a rate of 2 mL/min. The gallbladder volumes were determined simultaneously by ultrasonography. On test d 2, CJF (175 kcal/h) was started by the same route and at the same infusion rate. Analogous measurements were performed as indicated above. On test d 3, 100 microg of octreotide was administered subcutaneously and the previous procedure was repeated. The plasma level of CCK and glucagon and the serum levels of IRI and gastrin were determined by bioassay and radioimmunoassay (RIA), respectively.

RESULTS

Significant changes in hormone levels were not observed during jejunal saline perfusion. However, the levels of CCK (5.7+/-0.9 pmol), gastrin (10.6+/-1.3 pmol/L), IRI (27.2+/-5.8 microIU/mL), glucagon (322.8+/-32.4 pg/mL), and glucose (5.8+/-1.0 mmol/L) were significantly increased at 20 min during CJF vs the saline controls (2.0+/-0.3 pmol, 6.8+/-1.1 pmol/L, 7.8+/-0.4 microIU/mL, 172.8+/-33.4 pg/mL, and 4.5+/-0.5 mmol/L, respectively) and remained elevated at 40, 60, and 120 min. Octreotide pretreatment eliminated the increases in CCK, gastrin, IRI, and glucagon levels observed during CJF alone. The significant decrease in gallbladder volume during CJF was also prevented by octreotide pretreatment.

CONCLUSION

Continuous jejunal feeding (CJF) elicited significant increases in gastrointestinal (GI) regulatory hormone (cholecystokinin [CCK], gastrin, IRI, and glucagon) levels and evoked a consecutive gallbladder contraction. These biological responses are eliminated by octreotide pretreatment. Further clinical studies are needed to assess the eventual therapeutic effect of octreotide during CJF in patients with pancreatic pseudocyst.

Hereditary pancreatitis. Historical perspectives

Clinically, hereditary pancreatitis was not distinguishable from any other cause of pancreatitis. But astute clinical observations demonstrated an evolution toward chronic pancreatitis that could develop into carcinoma in some patients. A chromosomal abnormality was identified on chromosome 7q35, and then three separate genetic abnormalities were identified. It is now understood that a defect in trypsinogen is at the basis of the anomaly, and further developments should help identify new therapeutic approaches.

The effects of somatostatin and octreotide on experimental and human acute pancreatitis

The role of somatostatin and octreotide for AP has been studied for two decades, yet the data still remain inconclusive. The inconsistencies of the results of experimental studies and clinical trials may stem from the fact that the optimal therapeutic modality has not been determined. Furthermore, although they are similar in structure and physiologic activities, the mechanisms of action and effects of somatostatin and octreotide in AP may be different. Because the data are sparse, most reports, primarily those in the English literature, on the efficacy of somatostatin and octreotide in the management of AP were reviewed. Included are both nonrandomized and prospective, double-blind, clinical trials and studies on the effects of these agents on various experimental models of the disease. The results of the studies on somatostatin and octreotide are presented and discussed separately, with specific reference to the experimental and treatment details. The main focus of the review is the effect of subcutaneous and intravenous administration of octreotide. Analysis of the data suggests that somatostatin could not be recommended for AP and that the efficacy of subcutaneous administration of octreotide is also questionable. Theoretically, intravenous octreotide may be more appropriate for this condition, but recent results with this therapeutic method are limited and contradictory. Studies that would delineate the optimal therapeutical modality and the patient population most likely to respond to the treatment are prerequisite for large-scale clinical trials on the effects of octreotide on human pancreatitis.

Somatostatin attenuates microcirculatory impairment in acute sodium taurocholate-induced pancreatitis

Using in vivo microscopy, red blood cell (RBC) velocities, functional capillary density (FCD), and overall changes in capillary blood flow (PI) were estimated following intraductal infusion of sodium taurocholate (0.8 ml; 4%) alone or in combination with systemic administration of somstostatin (single bolus SMS 100 microg/100 g body wt). Sodium taurocholate mediated a significant transient decrease in RBC velocities and a sustained decrease in FCD, which were paralleled by dramatic flow heterogeneity. Therefore, a significant reduction in overall capillary blood flow was calculated. Additional SMS treatment reduced microcirculatory impairment as expressed by reduction of blood flow heterogeneity, a less rarified functional capillary density, and a recovery of RBC velocities and acinar capillary overall perfusion to control values. As a result of this microcirculatory improvement, pancreas histology revealed slightly less severe tissue damage compared to the non-SMS-treated pancreatitis group. These findings demonstrate that exogenous SMS infusion can improve microcirculatory failure in acute biliary pancreatitis, which should have a beneficial effect on the course of the disease.

Effects of high dose octreotide on retrograde bile salt-induced pancreatitis in rats

The effects of somatostatin and octreotide (a long acting somatostatin analogue) in acute pancreatitis are inconclusive. This study examined the prophylactic and therapeutic effects of different doses of octreotide on retrograde sodium taurodeoxycholate-induced acute necrotizing pancreatitis in rats. The rats were divided into 4 groups receiving subcutaneous injection of saline, octreotide 10 microg/kg, 20 microg/kg at 0, 8 and 16 h and octreotide 20 microg/kg at 5, 13 and 21 h, separately. The serum levels of amylase and lipase, pancreatic histopathology, mortality and hemodynamics were examined. Octreotide significantly reduced serum levels of amylase and lipase at 12 h and the degree of pancreatic edema, necrosis and hemorrhage at 18-24 h as compared to the control group. Prophylactic octreotide 10 microg/kg significantly decreased the 24-h mortality from 100% to 44.4% (p < 0.05). The 24-h mortality further reduced to 12.5% and 10% with prophylactic and therapeutic octreotide 20 microg/kg, respectively. The decrease of mean arterial pressure at 12 h was significantly lower in octreotide groups than in the control group. We conclude that octreotide improves pancreatic histopathology and survival in acute necrotizing pancreatitis in rats.

Clinical update: management of acute pancreatitis

The management of acute pancreatitis commences with confirming the diagnosis and establishing the aetiology. Improved methods of assessing the biliary tree may reduce the number of patients regarded as having idiopathic pancreatitis. Detailed clinical and laboratory protocols, designed to assess severity, have no major advantage over clinical assessment. The contrast-enhanced computed tomography scan is important to assess the degree of pancreatic necrosis and to detect local complications. The treatment of pancreatitis continues to be largely supportive. However, controlled studies support the use of antibiotics in severe acute pancreatitis and indicate a possible role for the use of octreotide and antioxidants. The place of endoscopic and surgical intervention is becoming better defined. Once an attack has passed, further investigation is often required in a bid to prevent further episodes of inflammation.

A randomized, controlled trial of octreotide in the management of patients with acute pancreatitis

CONCLUSION

In this study, octreotide was not found to be of benefit in the treatment of acute pancreatitis.

BACKGROUND

Somatostatin and its long-acting analog octreotide have both been proposed for the treatment of patients with acute pancreatitis, but neither agent has been adequately assessed in patients with severe attacks.

METHODS

Fifty-eight patients with moderate or severe acute pancreatitis who were admitted to hospitals within the west of Scotland over an 18-mo period were randomized to receive octreotide, 40 micrograms/h, by continuous i.v. infusion for 5 d, or placebo in addition to standard supportive therapy.

RESULTS

There was no significant difference in the incidence of complications (54% octreotide group and 40% placebo group) or mortality (octreotide group 18%; placebo group 20%).

Evaluation of the long-acting somatostatin analogue octreotide in the management of insulinoma in three dogs

The response of dogs with insulinoma to surgical and medical management is variable, with the majority developing intractable hypoglycaemia. A long-acting somatostatin analogue, Octreotide (SMS 201-995; Sandostatin) has been useful in the management of hypoglycaemia in humans with insulinoma, and preliminary reports suggest a beneficial clinical response in dogs with insulinoma. The present study objectively evaluated Octreotide in the management of three dogs with immunohistochemically confirmed insulinoma. Octreotide had no benefit over placebo, and little effect on circulating glucose and insulin concentrations despite clearly detectable plasma concentrations of Octreotide. No clinical improvement was apparent in two dogs given Octreotide over a period of two and three weeks. These results contrast with the positive clinical responses noted previously and indicate that further placebo controlled, objective studies are necessary before clear statements on the treatment of insulinoma with Octreotide are made.