Protective effects of MCP-1 inhibitor on a rat model of severe acute pancreatitis

BACKGROUND: Chemokines and their receptors play key roles in the pathogenesis of acute pancreatitis. This study aimed to establish a rat model of severe acute pancreatitis (SAP) for investigating monocyte chemotactic protein-1 (MCP-1) expression in the pathogenesis of the disease. We assessed the effects of the inhibitor of MCP-1, Bindarit, on SAP and explored the mechanisms underlying SAP. METHODS: Seventy-two Sprague-Dawley rats were randomly divided into a saline control group (group S), an SAP group (group P), and a Bindarit group (group T). The SAP model was induced by retrograde infusion of 4% sodium taurocholate into the bilio-pancreatic duct. Based on the SAP model, Bindarit was injected intraperitoneally in group T, and 0.5% methyl cellulose was injected intraperitoneally in groups S and P. In group S, saline was retrogradely infused into the bilpancreatic duct. Serum amylase levels and the histological changes in the pancreas were assessed at different time-points in each group. Expression of MCP-1 in serum was measured by enzyme-linked immunoadsorbent assay (ELISA). MCP-1 protein and mRNA expression levels were detected by immunohistochemistry, Western blotting, and semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR). RESULTS: Serum amylase levels in groups P and T were higher than those in group S. Serum amylase levels were significantly lower in group T than in group P at 6 and 12 hours after operation. The levels of MCP-1 in serum at 6 and 12 hours after operation in group P were significantly higher than in group S, and significantly lower in group T than in group P at 6 and 12 hours after operation. The pathological damage in the pancreas was milder in group T than in group P. MCP-1 protein and mRNA expression levels in the pancreas were higher in groups P and T than in group S. These expression levels were positively correlated with the pathological damage of pancreatic tissues. The activity of MCP-1 in group T was significantly lower than in group P. CONCLUSION: MCP-1 may play important roles in the pathogenesis of SAP. The data suggest that Bindarit ameliorates SAP by inhibiting the activity of MCP-1 in vivo. (Hepatobiliary Pancreat Dis Int 2010; 9: 201-207)

Diagnosis of pancreatic cancer by cytology and telomerase activity in exfoliated cells obtained by pancreatic duct brushing during endoscopy

BACKGROUND: Telomerase activity is reported to be specific and frequent in human pancreatic cancer. We conducted this study to assess the usefulness of monitoring telomerase activity in exfoliated cells obtained by pancreatic duct brushing during endoscopic retrograde cholangiopancreatography (ERCP) for the diagnosis of pancreatic cancer. METHODS: Exfoliated cells obtained by pancreatic duct brushing during ERCP from 21 patients (18 with pancreatic cancer, 3 with chronic pancreatitis) were examined. Telomerase activity was detected by polymerase chain reaction and telomeric repeat amplification protocol assay (PCR-TRAP-ELISA). RESULTS: D450 values of telomerase activity were 0.446 +/- 0.2700 in pancreatic cancer and 0.041 +/- 0.0111 in chronic pancreatitis. 77.8% (14/18) of patients with pancreatic cancer had cells with telomerase activity. None of the samples from patients with chronic pancreatitis showed telomerase activity, when the cutoff value of telomerase activity was set at 2.0. Cytological examination showed cancer cells in 66.7% (12/18) of the patients. CONCLUSIONS: Telomerase activity may be an early malignant event in pancreatic cancer development. Cytology and telomerase activity in cells obtained by pancreatic duct brushing may complement each other for the diagnosis of pancreatic cancer.