肠源性内毒素血症在胰腺炎发病中的作用

N-acetylcysteine ameliorates severe acute pancreatitis-associated intestinal injury in rats

AIM: To investigate the effects of treatment with n-acetylcysteine (NAC) on plasma levels of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and IL-10 and ICAM1 expression in small intestine tissue in rats with severe acute pancreatitis (SAP) and to explore the possible mechanisms involved.

METHODS: Seventy Wistar rats were randomly divided into a sham operation group (SO, n = 24), a SAP group (n = 24) and a NAC treatment group (n = 24). SAP was induced in rats by injecting 5.0% sodium taurocholate into the biliary-pancreatic duct. Rats in the SO group were given an infusion of normal saline instead. Rats in the NAC group underwent SAP induction and were given an intraperitoneal injection of NAC 1 hour before the operation, and rats in the SO group and SAP group were given an intraperitoneal injection of normal saline. Eight rats were sacrificed 6, 12 or 24 h after operation in each group. Plasma levels of amylase (AMY), endotoxin, diamine oxidase (DAO), D-lactic acid, TNF-α, IL-1β and IL-10 were measured. Pathologic changes in the small intestine were observed and scored. ICAM1 mRNA and protein expression in the small intestine was tested by real-time PCR and Western blot, respectively.

RESULTS: Compared to the SAP group, plasma levels of AMY, TNF-α and IL-β were significantly lower at all three time points (all P < 0.05) and serum levels of endotoxin, DAO and D- lactic acid were significantly lower at 12 and 24 h (both P < 0.05) in the NAC group. Serum levels of IL-10 in the NAC group were increased compared to the SAP group at all three time points. The pathology score of the small intestinal was significantly lower in the NAC group than the SAP group at 12 and 24 h. Although the mRNA expression of ICAM1 was increased at each time point in the SAP group compared with the SO group, it was significantly decreased in the NAC group compared with the SAP group (6 h: 1.13 ± 0.28 vs 2.37 ± 0.63; 12 h: 1.27 ± 0.34 vs 2.94 ± 0.82; 24 h: 1.19 ± 0.26 vs 2.68 ± 0.95; all P < 0.05). The protein expression of ICAM1 had the same trend as the mRNA expression between the NAC and SAP groups (6 h: 0.74 ± 0.11 vs 1.04 ± 0.25; 12 h: 0.88 ± 0.17 vs 1.25 ± 0.33; 24 h: 0.75 ± 0.13 vs 1.18 ± 0.22; all P < 0.05).

CONCLUSION: Administration of NAC ameliorates severe acute pancreatitis-associated intestinal injury in rats possibly by regulating plasma levels of TNF-α, IL-1β and IL-10 and inhibiting ICAM1 expression in the small intestine.

Ulinastatin in combination with glutamine dipeptide reduces serum levels of TNF-α, endotoxin and IL-6 in patients with severe acute pancreatitis

AIM: To evaluate the impact of protease inhibitor ulinastatin in combination with glutamine dipeptide on serum levels of TNF-α, endotoxin, IL-6 and IL-18 in patients with severe acute pancreatitis (SAP).

METHODS: Sixty-four SAP patients were divided into two groups: treatment group (n = 32) and control group (n = 32). The control group was treated with ulinastatin alone, while the treatment group was treated with ulinastatin in combination with glutamine dipeptide. The treatment lasted for 10 days. The changes in serum levels of TNF-α, endotoxin, IL-6 and IL-18 were determined by ELISA.

RESULTS: Compared to the control group, serum levels of TNF-α and endotoxin on days 7 and 10 (7 d: 38.83 ± 14.71 vs 51.92 ± 18.29; 0.46 ± 0.13 vs 0.71 ± 0.19; 10 d: 31.49 ± 12.65 vs 48.36 ± 15.43; 0.22 ± 0.07 vs 0.43 ± 0.15; all P < 0.05) and that of IL-6 on day 7 (117.68 ± 14.87 vs 163.43 ± 19.76, P < 0.05) were significantly lower in the treatment group. There was no significant difference in serum level of IL-18 between the two groups of patients (P > 0.05).

CONCLUSION: Ulinastatin in combination with glutamine dipeptide can reduce serum levels of TNF-α, endotoxin and IL-6 in SAP patients.

Enteral ecoimmunonutrition support alleviates hepatic injury in patients with severe acute pancreatitis

AIM: To explore the effects of different nutritional support regimens on hepatic injury in patients with severe acute pancreatitis (SAP).

METHODS: Eighty-six SAP patients with hepatic injury were randomly divided into three groups: parenteral nutrition (PN) group (n = 28), enteral nutrition (EN) group (n = 29) and ecoimmunonutrition (EIN) group (n = 29). All the patients received nutritional support for 14 days. The changes in plasma endotoxin and serum cytokine levels and hepatic function were determined.

RESULTS: The baseline levels of plasma endotoxin and serum tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) had no significant differences among the three groups. After 14 days of nutrition support, the levels of plasma endotoxin and serum TNF-α and IL-6 in the EIN group were 1.28 ng/L ± 0.17 ng/L, 30.13 ng/L ± 8.12 ng/L and 36.43 ng/L ± 8.24 ng/L, respectively, all significantly lower than those in the PN group and EN group (all P < 0.01 or 0.05). The hepatic function in the EIN group returned to normal levels after 14 days of nutrition support. The improvement in hepatic function achieved in the EIN group was significantly better than that achieved in the EN group.

CONCLUSION: EIN can help recover the balance of normal flora in the gut, reduce bacterial translocation, modulate immunological function, and attenuate the level of plasma endotoxin and serum cytokines, thereby alleviating hepatic injury in patients with SAP.