Effects of thalidomide in experimental models of post-endoscopic retrograde cholangiopancreatography pancreatitis

Experimental Acute Pancreatitis Models: History, Current Status, and Role in Translational Research

Acute pancreatitis is a potentially severe inflammatory disease that may be associated with a substantial morbidity and mortality. Currently there is no specific treatment for the disease, which indicates an ongoing demand for research into its pathogenesis and development of new therapeutic strategies. Due to the unpredictable course of acute pancreatitis and relatively concealed anatomical site in the retro-peritoneum, research on the human pancreas remains challenging. As a result, for over the last 100 years studies on the pathogenesis of this disease have heavily relied on animal models. This review aims to summarize different animal models of acute pancreatitis from the past to present and discuss their main characteristics and applications. It identifies key studies that have enhanced our current understanding of the pathogenesis of acute pancreatitis and highlights the instrumental role of animal models in translational research for developing novel therapies.

Nonsteroidal anti-inflammatory drugs alleviate severity of post-endoscopic retrograde cholangiopancreatography pancreatitis by inhibiting inflammation and reducing apoptosis

BACKGROUND AND AIM

The prophylactic effect of nonselective nonsteroidal anti-inflammatory drugs on post-ERCP (endoscopic retrograde cholangiopancreatography) pancreatitis has been observed for a long time. However, whether the selective nonsteroidal anti-inflammatory drugs possess similar abilities and the mechanisms by which nonsteroidal anti-inflammatory drugs work remain unclear. The present study aimed to determine the protective effects of nonsteroidal anti-inflammatory drugs on post-ERCP pancreatitis in a rat model and examine underlying mechanisms.

METHODS

Thirty-two female rats were equally and randomly divided into four groups: the sham group, post-ERCP pancreatitis model group, indomethacin-pretreated group, and parecoxib-pretreated group. Indomethacin or parecoxib was delivered 30 min prior to surgery; 24 h after post-ERCP pancreatitis establishment, the rats were sacrificed. Serum amylase and lipase activities, inflammatory cytokine release, pancreatic histopathological scores, neutrophil infiltration, and the expression pattern cyclooxygenase at the protein level and pancreatic apoptosis were quantified and analyzed.

RESULTS

Both indomethacin and parecoxib inhibited the activities of serum amylase and lipase and reduced the severity of pancreatic histopathology. Mechanistically, both drugs decreased the expression level of cyclooxygenase 2; however, they had no influence on the cyclooxygenase 1 protein level. Moreover, they reduced inflammatory cytokine release, neutrophil infiltration into the pancreas, and NF-κB p65 activation. Notably, we found that apoptotic cells in the pancreas were remarkably diminished after the administration of both nonsteroidal anti-inflammatory drugs.

CONCLUSIONS

Both selective and nonselective nonsteroidal anti-inflammatory drugs exert protective effects against post-ERCP pancreatitis by restraining inflammation and reducing acinar cell apoptosis through the inhibition of cyclooxygenase 2.

Thalidomide: an old drug with new action

Thalidomide is a drug that, since its development, has made history in the world of medicine--having been withdrawn and now has returned with a boom as an anticancer and immunomodulatory drug. However, its mode of action in various diseases (i.e. different types of hematologic malignancies, solid tumors) as well as in various infections (i.e. pneumonia, tuberculosis, HIV infection etc.) and related inflammatory conditions is not well understood. As the immune system plays an important role in the pathogenesis of both infection-related as well as noninfectious (i.e. cancer) inflammatory diseases, much research has been done in the past few years to discover and design better immunomodulatory agents. Such immunomodulatory agents should be able to target the immune system in such a way that host suffers minimum damage and normal function of the immune system remains intact. In the present review an attempt is made to highlight the immunomodulatory action of thalidomide in various pathologic conditions.

Thalidomide affects the skeletal system of ovariectomized rats

Apart from having written an inglorious chapter in the history of medicine, thalidomide is currently being intensely studied because of its multidimensional activity. The aim of this study was to examine the effects of thalidomide on the skeletal system in ovariectomized and non-ovariectomized rats. The experiments were carried out with female Wistar rats, divided into eight groups: sham-operated control rats; sham-operated rats receiving thalidomide at doses of 15, 30 or 60 mg/kg, po; ovariectomized control rats; ovariectomized rats receiving thalidomide at doses of 15, 30 or 60 mg/kg, po. The drug was administered for 4 weeks. Body mass gain and the mass of the uterus, liver, spleen and thymus were studied. Macrometric parameters and content of mineral substances, calcium and phosphorus in the femur, tibia and L-4 vertebra and histomorphometric parameters of the femur and tibia were examined. In the femur, the mechanical properties of the whole bone and of the femoral neck were examined. Thalidomide did not affect the skeletal system of the non-ovariectomized rats. Bilateral ovariectomy induced osteoporotic skeletal changes in mature female rats. The effects of thalidomide on the skeletal system of ovariectomized rats depended on the dose used. With a dose of 15 mg/kg, po, thalidomide counteracted some osteoporotic changes induced by estrogen deficiency. With a dose of 60 mg/kg, po, thalidomide intensified the destructive effects of estrogen deficiency on the rat skeletal system.

Effects in the control of edema of the papilla of Vater by epinephrine saline irrigation after endoscopic retrograde cholangiopancreatography in an endoscopy center in Japan, 2003 to 2007: exploratory retrospective analysis to evaluate the characteristics of eligible patients with a focus on serum amylase levels

OBJECTIVE

To evaluate the effects of localized irrigation with epinephrine saline after endoscopic retrograde cholangiopancreatography (ERCP).

PATIENTS AND METHODS

One hundred and fourteen patients who underwent ERCP in our institute were treated with or without irrigation using epinephrine diluted in saline after ERCP to prevent post-ERCP pancreatitis. The serum amylase levels, white blood cell counts, and urine amylase levels were measured at 24 and 48 hours after ERCP.

RESULTS

The treatment resulted in improvements in all items. A univariate analysis of the explanatory variables between the treatment and untreated groups revealed the treatment to be effective, but not statistically significant. Gender and cannulation of the pancreatic duct were the only variables with significant partial regression coefficients in the multiple regression model with all explanatory variables (p=0.045). When a stratified analysis was conducted using gender as a moderator variable, the treatment became a significant preventive factor (p=0.038), and cannulation of the pancreatic duct was a significant risk factor (p=0.027) in female patients.

CONCLUSION

We suggest that irrigating with epinephrine saline into the papilla may be effective for preventing pancreatitis in female patients who received ERCP with cannulation of their pancreatic duct.

Thalidomide: mechanisms of action

The classification of thalidomide as an orphan drug with anti-inflammatory actions has led to its off-label use in conditions refractory to other medications. Although the observed clinical effects of thalidomide suggest it to have immunomodulatory capabilities, the mechanism of action is unclear. Here we review both the positive and negative studies of thalidomide at the bench in order to improve our understanding of the possible mechanisms of this drug in treating a variety of diseases at the bedside. Studies on the effects of thalidomide on the innate and adaptive immune system as well as tumorigenesis and angiogenesis are discussed.