Pancreatic elastase is proven to be a mannose-binding protein--implications for the systemic response to pancreatitis

Biochemical changes in lipid and protein metabolism caused by mannose-Raman spectroscopy studies

Biochemical analysis of human normal bronchial cells (BEpiC) and human cancer lung cells (A549) has been performed by using Raman spectroscopy and Raman imaging. Our approach provides a biochemical compositional mapping of the main cell components: nucleus, mitochondria, lipid droplets, endoplasmic reticulum, cytoplasm and cell membrane. We proved that Raman spectroscopy and Raman imaging can distinguish successfully BEpiC and A549 cells. In this study, we have focused on the role of mannose in cancer development. It has been shown that changes in the concentration of mannose can regulate some metabolic processes in cells. Presented results suggest lipids and proteins can be considered as Raman biomarkers during lung cancer progression. Analysis obtained for bands 1444 cm-1, and 2854 cm-1 characteristic for lipids and derivatives proved that the addition of mannose reduced levels of these compounds. Results obtained for protein compounds based on bands 858 cm-1, 1004 cm-1 and 1584 cm-1 proved that the addition of mannose increases the values of protein in BEpiC cells and blocks protein glycolisation in A549 cells. Noticing Raman spectral changes in BEpiC and A549 cells supplemented with mannose can help to understand the mechanism of sugar metabolism during cancer development and could play in the future an important role in clinical treatment.

Liver proteome analysis of grass carp (Ctenopharyngodon idellus) following treatment with enrofloxacin

Enrofloxacin is widely used for the prevention and control of bacterial diseases in aquaculture. The liver is crucial for enrofloxacin metabolism, but enrofloxacin can induce liver damage. Herein, we explored proteomic changes in the liver of grass carp (Ctenopharyngodon idellus) following treatment with enrofloxacin using isobaric tag for relative and absolute quantitation (iTRAQ) technology. All experiments included two biological replicates and blank controls. Among the 3082 proteins identified, 103 were differentially abundant, comprising 49 up- and 54 downregulated proteins. Gene Ontology (GO) annotation identified macromolecular complex (63.60%), intracellular non-membrane-bound organelle (51.50%), and non-membrane-bound organelle (51.50%) as the most enriched cellular component terms. Structural molecule activity (26.80%), structural constituent of ribosome (17.90%), and calcium ion binding (16.10%) were the top three molecular function terms. Organic substance biosynthetic process (37.80%), biosynthetic process (37.80%), and protein metabolic process (37.80%) were the top three biological process terms. The Kyoto Encyclopaedia of Genes and Genomes (KEGG) pathway analysis found 17 enriched KEGG pathways, with protein digestion and absorption, extracellular matrix (ECM)-receptor interactions, and ribosome and focal adhesion the most significant (p < 0.001). Analysis of the most enriched pathways revealed that chymotrypsin-like precursor, pancreatic elastase precursor, Na+/K+ transporting ATPase, collagen, and dermatopontin were upregulated, while ribosomal proteins, alpha-actinin, and myosin light chain were downregulated. These findings suggest that enrofloxacin affects liver function and has a risk of inducing an inflammatory response in extrahepatic organs.

Complement in Pancreatic Disease-Perpetrator or Savior?

The complement system is a major pillar of the humoral innate immune system. As a first line of defense against pathogens, it mediates early inflammatory response and links different branches of humoral and cellular immunity. Disorders affecting the exocrine pancreas, such as acute pancreatitis, potentially lead to a life-threatening systemic inflammatory response with aberrant activation of complement and coagulation cascades. Pancreatic proteases can activate key effectors of the complement system, which in turn drive local and systemic inflammation. Beyond that, the extent of pancreas–complement interaction covers complex pro- and anti-inflammatory mechanisms, which to this day remain to be fully elucidated. This review provides a comprehensive overview of the pathophysiological role of complement in diseases of the exocrine pancreas, based on existing experimental and clinical data. Participation of complement in acute and chronic pancreatitis is addressed, as well as its role in tumor immunology. Therapeutic strategies targeting complement in these diseases have long been proposed but have not yet arrived in the clinical setting.

Mannose-mediated inhibitory effects of PA-MSHA on invasion and metastasis of hepatocellular carcinoma via EGFR/Akt/IκBβ/NF-κB pathway

BACKGROUND & AIMS

Elevation of high-mannose glycans is a common feature of malignant cells and has been suggested to be the basis for alternative cancer therapy for several years. Here we want to investigate the antitumour effect of pseudomonas aeruginosa-mannosesensitive haemagglutinin (PA-MSHA), a genetically engineered heat-inactivated PA strain with mannose-sensitive binding activity, on hepatocellular carcinoma (HCC).

METHODS

Tumourigenicity and metastatic potentials of HCC were studied after PA-MSHA treatment by utilizing the in vitro/in vivo model of HCC. Expression of apoptosis-associated proteins and epithelial-mesenchymal transition (EMT) related genes were evaluated, and possible signalling pathways involved were investigated.

RESULTS

PA-MSHA induced significant cell proliferation inhibition and cell cycle arrest of HCC through decreasing the levels of cyclins D1, cyclins E, CDK2, CDK4, proliferating cell nuclear antigen (PCNA), and increasing the level of p21 and p27. Moreover, PA-MSHA suppressed the invasion, migration and adhesion of HCC through inhibiting epithelial-mesenchymal transition (EMT). PA-MSHA also inhibited EGFR/Akt/IκBβ/NF-κB pathway and overexpression of NF-κB significantly abrogated PA-MSHA induced EMT inhibition. In addition, competitive inhibition of the mannose binding activity of PA-MSHA by D-mannose significantly blocked its effect on cell cycle arrest and EMT. PA-MSHA also abrogated lung metastasis of HCC and significantly inhibited tumour growth in the in vivo study.

CONCLUSIONS

Our study demonstrated the essential role of EGFR/Akt/IκBβ/NF-κB pathway in the inhibitory effect of PA-MSHA on invasion and metastasis of HCC through suppressing EMT, and revealed an attractive prospect of PA-MSHA as a novel candidate agent in the treatment of HCC.

Risk factor of surgical site infection after pancreaticoduodenectomy

BACKGROUND

Although surgical site infection (SSI) following pancreaticoduodenectomy is a common complication, the risk factors remain unclear.

PATIENTS AND METHODS

A retrospective study of 408 consecutive patients undergoing pancreaticoduodenectomy was conducted and the risk factors for SSI were assessed. The bacterial composition was also analyzed.

RESULTS

Sixty-one patients developed incisional SSI, and 195 developed organ/space SSI. A multivariate analysis identified that length of operation>480 min (odds ratio [OR] 3.22), main pancreatic duct (MPD)≤3 mm (OR 2.18), and abdominal wall thickness>10 mm (OR 2.16) were significant risk factors for incisional SSI. The development of pancreatic fistula (OR 7.56), use of semi-closed drainage system (OR 3.68), body mass index>23.5 kg/m2 (OR 3.04), MPD≤3 mm (OR 2.21), and length of operation>480 min (OR 1.78) were significantly associated with organ/space SSI. Bacterial isolation at the SSI foci revealed that gut-derived micro-organisms were the predominant bacterial species.

CONCLUSIONS

The presence of pancreatic fistula was the strongest risk factor for organ/space SSI. Efforts to reduce the development of pancreatic fistulas, to decrease length of operation, and to use a closed drainage system would decrease the incidence of SSI following pancreaticoduodenectomy. If SSI that requires antibacterial treatment occurs, then the treatment should target enterobacteria.

Use of gene expression profiles in cells of peripheral blood to identify new molecular markers of acute pancreatitis

HYPOTHESIS

Blood leukocytes play a major role in mediating local and systemic inflammation during acute pancreatitis. We hypothesize that peripheral blood mononuclear cells (PBMCs) in circulation exhibit unique changes in gene expression and could provide a "reporter" function that reflects the inflammatory response in the pancreas with acute pancreatitis.

DESIGN

To determine specific changes in blood leukocytes during acute pancreatitis, we studied the gene transcription profile in PBMCs in a rat model of experimental pancreatitis (sodium taurocholate). Normal rats, saline controls, and a model of septic shock were used as a controls. Complementary RNA obtained from PBMCs of each group (n = 3 in each group) were applied to Affymetrix rat genome DNA GeneChip arrays. Main Outcome Measure Changes in gene expression.

RESULTS

From the 8799 rat genes analyzed, 140 genes showed unique significant changes in their expression in PBMCs during the acute phase of pancreatitis, but not in sepsis. Among the 140 genes, 57 were up-regulated, while 69 were down-regulated. Platelet-derived growth factor receptor, prostaglandin E(2) receptor, and phospholipase D(1) were among the top up-regulated genes. Others included genes involved in G protein-coupled receptor and transforming growth factor beta-mediated signaling pathways, while genes associated with apoptosis, glucocorticoid receptors, and even the cholecystokinin receptor were down-regulated.

CONCLUSIONS

Microarray analysis in transcriptional profiling of PBMCs showed that genes that are uniquely related to molecular and pancreatic function display differential expression in acute pancreatitis. Profiling genes obtained from an easily accessible source during severe pancreatitis may identify surrogate markers for disease severity.

Pathogenesis and treatment of acute pancreatitis with liver injury

Acute pancreatitis is a frequent acute abdomen in clinic, causes damages not only to pancreas, but also to distant organs. Liver is one of the mainly involved organs. The development of liver injury may aggravate pancreatitis. The pathogenesis of acute pancreatitis with liver injury is mainly related to cytokines, pancreatic enzyme, oxidative stress, microcirculation disturbance, apoptosis and pancreatitis-associated ascitic fluid, etc. Its treatment is also to eradicate these factors. However, more methods are still under animal studies. Their clinical application requires further study.

Increased plasma levels of IL-6 and IL-8 are associated with surgical site infection after pancreaticoduodenectomy

OBJECTIVES

Cytokines and chemokines potentially modulate postoperative immune response. Association of circulating cytokines and chemokines with postoperative infectious complications after pancreaticoduodenectomy was evaluated.

METHODS

Plasma concentrations of interleukin (IL) 6, IL-10, IL-8, macrophage chemoattractant protein 1, heat shock protein 70, and amylase, as well as amylase levels in peritoneal exudative fluid, were measured perioperatively in 60 consecutive patients who underwent pancreaticoduodenectomy.

RESULTS

Of the 60 patients, 27 patients had surgical site infection (SSI), including peritoneal infection in all, intra-abdominal abscess in 14, and radiologically visualized pancreatic leakage in 6. Postoperative plasma levels of IL-6, IL-8, and macrophage chemoattractant protein 1, as well as peritoneal amylase levels, were significantly higher in patients with SSI than in those without SSI (P < 0.05). Nonpancreatic cancer as a histopathologic diagnosis, high pancreatic juice flow, and increased levels of IL-6 and IL-8 were independently associated with SSI (P < 0.05) in multiple logistic regression analysis. Plasma levels of IL-6 and IL-10 among patients with SSI were significantly higher in those with pancreatic leakage than in those without leakage.

CONCLUSIONS

These results suggest that, in addition to pancreatic exocrine function, IL-6 and IL-8 are associated with postoperative SSI, including pancreatic leakage after pancreaticoduodenectomy.

Targeted inhibition of gene expression of pancreatitis-associated proteins exacerbates the severity of acute pancreatitis in rats

BACKGROUND

Pancreatitis-associated protein (PAP) is a secretory protein not normally expressed in healthy pancreas but highly induced during acute pancreatitis. While PAP has been shown to be anti-bacterial and anti-apoptotic in vitro, its definitive biological function in vivo is not clear.

METHODS

To elucidate the function of PAP, antisense oligodeoxyribonucleotides (AS-PAP) targeting all three isoforms of PAP were administered via intrapancreatic injections (5 mg kg day, 2 days) to rats prior to induction of pancreatitis.

RESULTS

Severity of pancreatitis and cytokine gene expression in peripheral blood mononuclear cells (PBMC) were evaluated. Administration of AS-PAP, but not the scrambled oligodeoxyribonucleotide (SC-PAP) control, reduced pancreatitis-induced PAP expression by 55.2 +/- 6.4%, 44.0 +/- 8.9%, and 38.9 +/- 10.7% for PAP isoforms I, II, and III, respectively, compared to saline-treated controls (P < 0.05 for all). Inhibition of PAP expression significantly worsened pancreatitis: serum amylase activity, pancreas wet weight (reflecting edema), and serum C-reactive protein levels all increased in AS-PAP-treated animals compared to SC-PAP-treated controls (by 3.5-, 1.7-, and 1.7-fold, respectively; P < 0.05 for all). Histopathologic evaluation of pancreas revealed worsened edema, elevated leukocyte infiltration, and fat necrosis after AS-PAP treatment. Gene expressions of IL-1 microm and IL-4 were significantly higher in PBMC isolated from AS-PAP-treated rats compared to SC-PAP controls.

CONCLUSION

This is the first in vivo evidence indicating that PAP mediates significant protection against pancreatic injury. Our data suggest that PAP may exert its protective function by suppressing local pancreatic as well as systemic inflammation during acute pancreatitis.