Administration of warfarin accelerates the recovery in ischemia/reperfusion-induced acute pancreatitis

Acute pancreatitis is associated with activation of coagulation and there is a close relationship between coagulation and the severity of this disease. Administration of anticoagulants such as heparin or acenocoumarol has shown to reduce the severity of acute pancreatitis and accelerate the recovery. The aim of the current study was to determine the impact of warfarin administration on the course of ischemia/reperfusion-induced acute pancreatitis. Acute pancreatitis was induced in rats by pancreatic ischemia followed by reperfusion. Vehicle (1 ml/dose) or warfarin (45, 90 or 180 μg/kg/dose in 1 ml of vehicle) were administered intragastrically once a day. The first dose of warfarin was given 24 h after the start of pancreatic reperfusion. The severity of acute pancreatitis was assessed 2, 5, 9 and 14 days after the beginning of pancreatic reperfusion. Treatment with warfarin reduces pancreatic damage and accelerates recovery in histological examination and this effect is accompanied by a faster reduction in serum activity of pancreatic digestive enzymes, lipase and amylase. In addition, warfarin led to an earlier decrease in serum concentration of pro-inflammatory interleukin-1β and plasma level of D-dimer. These effects were associated with an improvement of pancreatic blood flow. We conclude that warfarin exhibits a therapeutic effect in acute pancreatitis evoked by pancreatic ischemia followed by reperfusion.

Therapeutic effect of exogenous ghrelin in the healing of gingival ulcers is mediated by the release of endogenous growth hormone and insulin-like growth factor-1

Ghrelin, an acylated 28-amino acid polypeptide, was primary isolated from the stomach, and the stomach is a main source of circulating ghrelin. Ghrelin strongly and dose-dependently stimulates release of growth hormone from the anterior pituitary, as well as increases food intake and fat deposition. Previous studies showed that ghrelin exhibits protective and therapeutic effect in different parts of the gastrointestinal system, including the oral cavity. The aim of present study was to examine the role of growth hormone and insulin-like growth factor-1 (IGF-1) in the healing of gingival ulcers. Studies were performed on rats with the intact pituitary gland and hypophysectomized rats. In anesthetized rats, chronic ulcers of the gum were induced by acetic acid. Rats were treated intraperitoneally twice a day with saline or ghrelin (4, 8 or 16 nmol/kg/dose) for six days. In pituitary-intact rats, administration of ghrelin significantly increased serum concentration of growth hormone and IGF-1 and this effect was associated with a significant increase in the healing rate of gingival ulcers. Moreover, treatment with ghrelin increased mucosal blood flow and DNA synthesis in the gum, while a local inflammation was decreased what was observed as a reduction in mucosal concentration of pro-inflammatory interleukin-1β. Hypophysectomy decreased serum level of growth hormone below a detection limit; whereas serum concentration of IGF-1 was reduced by 90%. On the other hand, removal of the pituitary gland was without any significant effect on the healing rate of gingival ulcers or on the ulcer-induced increase in DNA synthesis and concentration of pro-inflammatory interleukin-1β in gingival mucosa. Administration of ghrelin failed to affect serum level of growth hormone and IGF-1 in hypophysectomized rats, and was without any effect on the healing rate of gingival ulcers, mucosal blood flow, DNA synthesis or concentration of interleukin-1β in gingival mucosa. Neither induction of gingival ulcers nor hypophysectomy nor administration of ghrelin significantly affected serum concentration of pro-inflammatory interleukin-1β. We concluded that endogenous growth hormone and IGF-1 were involved in the therapeutic effect of exogenous ghrelin in the healing of gingival mucosa damage.

Therapeutic effect of ghrelin in the course of ischemia/reperfusion-induced acute pancreatitis

BACKGROUND

Protective effect of pretreatment with ghrelin against different forms of acute pancreatitis (AP) has been recently reported. Moreover, the healing properties of this peptide have been proved in AP evoked by cerulein. However, no studies have investigated whether the administration of ghrelin affects the course of ischemia/reperfusion-induced AP.

AIM

The aim of this study was to evaluate the impact of ghrelin therapy on the course of necrotizing inflammation of the pancreas and to test its impact on peroxidation of lipids and antioxidant defense system in the acutely inflamed pancreas.

METHODS

Acute inflammation of the pancreas was triggered by pancreatic ischemia which was then followed by reperfusion of the gland. Ghrelin (8 nmol/kg/dose) was administered to intraperitoneally twice daily, 24h after the initiation of AP. The impact of ghrelin on the course of necrotizing pancreatitis was evaluated between 1 and 21 days, and involved histological, functional, and biochemical analyses.

RESULTS

Treatment with ghrelin ameliorated morphological signs of pancreatic damage including edema, acinar cells vacuolization, hemorrhages, acinar necrosis, leukocytic infiltration of the gland, and led to its earlier regeneration. These effects were accompanied by an improvement in pancreatic blood flow, enhanced DNA synthesis, reduced serum level of pro- inflammatory interleukin-1β, decreased levels of malondialdehyde and an enhanced superoxide dismutase activity in pancreatic tissue.

CONCLUSIONS

Ghrelin exerts a pronounced therapeutic effect against ischemia-reperfusion-induced pancreatitis. The mechanisms involved are likely multifactorial and are mediated by its anti-inflammatory, as well as anti-oxidative properties.

Pretreatment with low doses of acenocoumarol inhibits the development of acute ischemia/reperfusion-induced pancreatitis

Coagulative disorders are known to occur in acute pancreatitis and are related to the severity of this disease. Various experimental and clinical studies have shown protective and therapeutic effect of heparin in acute pancreatitis. Aim of the present study was to determine the influence of acenocoumarol, a vitamin K antagonist, on the development of acute pancreatitis. Studies were performed on male Wistar rats weighing 250 - 270 g. Acenocoumarol at the dose of 50, 100 or 150 μg/kg/dose or vehicle were administered once a day for 7 days before induction of acute pancreatitis. Acute pancreatitis was induced in rats by pancreatic ischemia followed by reperfusion. The severity of acute pancreatitis was assessed after 5-h reperfusion. Pretreatment with acenocoumarol given at the dose of 50 or 100 μg/kg/dose reduced morphological signs of acute pancreatitis. These effects were accompanied with a decrease in the pancreatitis-evoked increase in serum activity of lipase and serum concentration of pro-inflammatory interleukin-1β. Moreover, the pancreatitis-evoked reductions in pancreatic DNA synthesis and pancreatic blood flow were partially reversed by pretreatment with acenocoumarol given at the dose of 50 and 100 μg/kg/dose. Administration of acenocoumarol at the dose of 150 μg/kg/dose did not exhibit any protective effect against ischemia/reperfusion-induced pancreatitis. We concluded that pretreatment with low doses of acenocoumarol reduces the severity of ischemia/reperfusion-induced acute pancreatitis.

Role of hormonal axis, growth hormone - IGF-1, in the therapeutic effect of ghrelin in the course of cerulein-induced acute pancreatitis

Ghrelin is a ligand for growth hormone secretagogue receptor and stimulates release of growth hormone (GH). Recent studies have shown that treatment with ghrelin exhibits protective and therapeutic effect in the course of experimental pancreatitis. The aim of present study was to examine the role of GH and insulin-like growth factor-1 (IGF-1) in these effects. Acute pancreatitis was induced by cerulein. Study was performed on pituitary-intact hypophysectomized rats. Ghrelin was administered twice a day at the dose of 8 nmol/kg/dose. IGF-1 was given twice a day at the dose of 20 nmol/kg/dose. The severity of acute pancreatitis was assessed 0 h or 1, 2, 3, 5 and 10 days after the last dose of cerulein. Administration of cerulein led to the development of acute edematous pancreatitis. In pituitary-intact rats, treatment with ghrelin reduced biochemical indexes of the severity of acute pancreatitis and morphological signs of pancreatic damage, leading to faster regeneration of the pancreas reduction in serum concentration of pro-inflammatory interleukin-1β and decrease in serum activity of amylase and lipase. These effects were accompanied with an improvement of pancreatic blood flow and an increase in pancreatic DNA synthesis. Hypophysectomy delayed the healing of the pancreas and abolished the therapeutic effect of ghrelin. In hypophysectomized rats with pancreatitis, treatment with IGF-1 exhibits therapeutic effect similar to that observed in ghrelin-treated rats with the intact pituitary. We conclude that therapeutic effect of ghrelin in cerulein-induced pancreatitis is indirect and depends on the release of GH and IGF-1.

Therapeutic effect of ghrelin in the course of cerulein-induced acute pancreatitis in rats

Recent studies have shown that pretreatment with ghrelin exhibits protective effect in the gut. Administration of ghrelin reduces gastric mucosal damage, as well as inhibits the development of experimental pancreatitis. However, this protective effect requires administration of ghrelin before gastric or pancreatic damage and thus has a limited clinical value. The aim of present study was to assess the influence of ghrelin administered after development of acute pancreatitis on the course of this disease. Acute pancreatitis was induced by cerulein. Ghrelin was administered twice a day for 1, 2, 4, 6 or 9 days at the dose of 4, 8 or 16 nmol/kg/dose. The first dose of ghrelin was given 24 hours after last injection of cerulein. The severity of acute pancreatitis was assessed between 0 h and 10 days after cessation of cerulein administration. Administration of caerulein led to the development of acute edematous pancreatitis and maximal severity of this disease was observed 24 hours after induction of pancreatitis. Treatment with ghrelin reduced morphological signs of pancreatic damage such as pancreatic edema, leukocyte infiltration and vacuolization of acinar cells, and led to earlier regeneration of the pancreas. Also biochemical indexes of the severity of acute pancreatitis, serum activity of lipase and amylase were significantly reduced in animals treated with ghrelin. These effects were accompanied by an increase in the pancreatic DNA synthesis and a decrease in serum level of pro-inflammatory interleukin-1b. Administration of ghrelin improved pancreatic blood flow in rats with acute pancreatitis. We conclude that: (1) treatment with ghrelin exhibits therapeutic effect in caerulein-induced experimental acute pancreatitis; (2) this effect is related, at least in part, to the improvement of pancreatic blood flow, reduction in proinflammatory interleukin-1beta and stimulation of pancreatic cell proliferation.

Pretreatment with obestatin inhibits the development of cerulein-induced pancreatitis

Obestatin is a peptide derived from the proghrelin, a common prohormone for ghrelin and obestatin. Obestatin, like the ghrelin has been originally extracted from rat stomach, and the stomach seems to be a major source of circulating obestatin. Previous studies have shown that administration of ghrelin exhibits protective effect in the pancreas, inhibiting the development of acute pancreatitis. Recent study has shown that obestatin promotes survival of beta-cells and pancreatic islets. Aim of the present study was to investigate the influence of obestatin administration on the development of cerulein-induced pancreatitis. Studies were performed on male Wistar rats. Acute pancreatitis was induced by cerulein given intraperitoneally 5 times at a dose of 50 microg/kg/dose with 1-h intervals. Obestatin was injected twice intraperitoneally at the dose of 4, 8 or 16 nmol/kg/dose. In control saline-treated rats, obestatin was without effect on pancreatic morphology, serum activity of pancreatic enzymes, serum level of pro-inflammatory interleukin-1beta or pancreatic cells proliferation. In animals with induction of acute pancreatitis, morphological examination showed that administration of obestatin decreased pancreatic leukocyte infiltration and vacuolization of acinar cells. These effects were accompanied by reduction in the pancreatitis-evoked increase in serum level of pancreatic digestive enzymes, lipase amylase and poly-C ribonuclease. Obestatin administered at the highest dose of 16 nmo/kg/dose reduced serum activity of these enzymes by 33, 42 and 44%, respectively. Also serum concentration of pro-inflammatory interleukin-1beta was decreased by obestatin in rats with acute pancreatitis; whereas the pancreatitis-evoked decrease in pancreatic blood flow and pancreatic DNA synthesis was partially reversed. Administration of obestatin reduces the severity of cerulein-induced acute pancreatitis. This effect is related, at least in part, to the improvement of pancreatic blood flow and reduction in proinflammatory interleukin-1beta release.

Protective and therapeutic effect of heparin in acute pancreatitis

The initiation and progression of acute pancreatitis is associated with disturbances in pancreatic microcirculatory. Microcirculatory disorders contribute to multiorgan dysfunction syndrome in the course of acute pancreatitis. The aim of this study was to determine the influence of heparin administration on the development and the course of ischemia/reperfusion-induced pancreatitis.

METHODS

Acute pancreatitis was induced in rats by pancreatic ischemia followed by reperfusion. In the first series of studies, heparin was administered 0.5 h before induction of acute pancreatitis and the severity of acute pancreatitis was assessed after 6-h reperfusion. In the second series of studies, heparin was administered twice a day, starting 24 h after the initiation of reperfusion. In both series of studies, heparin was administered subcutaneously at the dose of 150 U/kg.

RESULTS

Treatment with heparin, before induction of pancreatitis, inhibits the development of morphological signs of acute pancreatitis and reduced the pancreatitis-evoked increase in plasma level of pancreatic enzymes and pro-inflammatory interleukin-1beta. These effects have been accompanied with improvement of pancreatic blood flow, pancreatic DNA synthesis and reduction in plasma concentration of D-dimer. Administration of heparin after induction of acute pancreatitis accelerates normalization of pancreatic histology, and reduces biochemical markers of the severity of acute pancreatitis. These effects have been accompanied with the improvement of pancreatic circulation, increase in APTT and reduction in plasma D-dimer level.

CONCLUSIONS

Treatment with heparin inhibits the development of ischemia/reperfusion-induced pancreatitis and accelerates pancreatic regeneration in the course of this disease.

Pancreatic exocrine insufficiency is not common in HNF-1alpha MODY

AIMS

Exocrine pancreatic insufficiency has been described in Type 1 and Type 2 diabetes. The hepatocyte nuclear factor (HNF)-1alpha gene associated with maturity-onset diabetes of the young (MODY3) is expressed in several organs, including the exocrine pancreas. The aim of this study was to determine the prevalence of exocrine pancreas dysfunction in HNF-1alpha MODY patients.

METHODS

Thirty-one diabetic HNF-1alpha MODY patients (mean age 37.2 +/- 14.6 years) and 35 healthy control subjects (39.1 +/- 13.9 years) participated. In addition, 25 Type 1 diabetic (T1DM) subjects were also examined (mean age 30.6 +/- 10.1 years). Exocrine pancreas function was assessed by measurement of stool elastase 1 (E1) activity. All diabetic patients and control subjects completed a gastrointestinal (GI) symptoms questionnaire.

RESULTS

In all but two individuals, stool E1 levels were normal (> 200 microg/g). The only case of severely impaired pancreas exocrine function (E1 = 47.5 microg/g) was observed in the MODY3 group. The mean stool E1 elastase level in the HNF-1alpha MODY group was significantly lower than in the control subjects (401.0 +/- 118.4 vs. 482.7 +/- 151.1 microg/g, P = 0.001). Similarly, E1 levels in T1DM were lower than in control subjects (344.8 +/- 132.1 microg/g, P = 0.001); one patient with a moderate enzyme decrease was identified in this group. In addition, more frequent GI complaints were reported by HNF-1alpha MODY patients when compared with control subjects and also with T1DM patients.

CONCLUSION

Pancreatic exocrine insufficiency is not common in HNF-1alpha MODY diabetic patients, although their stool E1 levels are lower than in healthy control subjects.

Correlation of peripheral blood monocyte and neutrophil direct counts with plasma inflammatory cytokines and TNF-alpha soluble receptors in the initial phase of acute pancreatitis

MATERIAL

The relationship between direct count of peripheral blood leucocyte populations and plasma concentrations of IL-6, IL-8, sTNFR-55 and sTNFR-75 during five initial days of acute pancreatitis was studied.

RESULTS

Most significant relationship was found for monocytes, which correlated with sTNFR-55 (R = 0.38, p < 0.05) and sTNFR-75 (R = 0.41, p < 0.05 and R = 0.55, p < 0.01 during 1st and 2nd day, respectively). Later, in days 2, 3 and 4 an interrelation between monocytes and IL-6 (R = 0.49 to R = 0.41, p < 0.01) was observed. Monocytes also correlated with IL-8 in days 2 and 3 (R = 0.41, p < 0.05 and R = 0.43, p < 0.01, respectively). Neutrophil count correlated with IL-6 in days 3 and 4 (R = 0.34, p < 0.05 and R = 0.56, p < 0.01, respectively) and with IL-8 in the 4th day only (R = 0.39, p < 0.05). No significant correlations of lymphocyte, eosinophil and basophil direct counts with cytokines and receptors during the initial 5 days of AP were found.

CONCLUSIONS

Observed relationships between monocyte direct counts and plasma cytokine levels reflect monocytes involvement in the development of acute pancreatitis.

Extract of grapefruit-seed reduces acute pancreatitis induced by ischemia/reperfusion in rats: possible implication of tissue antioxidants

Grapefruit seed extract (GSE) has been shown to exert antibacterial, antifungal and antioxidant activity possibly due to the presence of naringenin, the flavonoid with cytoprotective action on the gastric mucosa. No study so far has been undertaken to determine whether this GSE is also capable of preventing acute pancreatic damage induced by ischemia/reperfusion (I/R), which is known to result from reduction of anti-oxidative capability of pancreatic tissue, and whether its possible preventive effect involves an antioxidative action of this biocomponent. In this study carried out on rats with acute hemorrhagic pancreatitis induced by 30 min partial pancreatic ischemia followed by 6 h of reperfusion, the GSE or vehicle (vegetable glycerin) was applied intragastrically in gradually increasing amounts (50-500 microl) 30 min before I/R. Pretreatment with GSE decreased the extent of pancreatitis with maximal protective effect of GSE at the dose 250 microl. GSE reduced the pancreatitis-evoked increase in serum lipase and poly-C specific ribonuclease activity, and attenuated the marked fall in pancreatic blood flow and pancreatic DNA synthesis. GSE administered alone increased significantly pancreatic tissue content of lipid peroxidation products, malondialdehyde and 4-hydroxyalkens, and when administered before I/R, GSE reduced the pancreatitis-induced lipid peroxidation. We conclude that GSE exerts protective activity against I/R-induced pancreatitis probably due to the activation of antioxidative mechanisms in the pancreas and the improvement of pancreatic blood flow.

Poly-C specific ribonuclease activity correlates with increased concentrations of IL-6, IL-8 and sTNFR55/sTNFR75 in plasma of patients with acute pancreatitis

Plasma pancreatic-type Poly-C specific ribonuclease (P-RNase)-enzyme activity increases in patients with acute pancreatitis (AP) who develop pancreatic necrosis and severe disease course. It is considered as a marker of pancreatic tissue destruction. The aim of this study was to estimate interrelations between major inflammatory cytokines such as: interleukin 6 (IL-6), interleukin 8 (IL-8) and tumor necrosis factor soluble receptors: sTNFR55 and sTNFR75 output, and plasma P-RNase activity. The study was carried out in a group of 56 patients with AP, where 20 developed pancreatic necrosis. It was found that serum P-RNase concentration and levels of all studied inflammatory cytokines significantly increase already in the first day from diagnose of the disease (2.5 folds for P-RNase, 20 for IL-8, about 200 for IL-6 and 1.5 for receptors, respectively). In the first day from admission to hospital, P-RNase activity significantly correlated with plasma concentration of studied inflammatory cytokines. The most pronounced correlation was found for P-RNase and IL-6 in days 1-4 from diagnose, manifested by Pearson correlation r coefficients amounting to 0.86, 0.79, 0.60 and 0.57 respectively (p<0.001). Dividing the studied AP patients into two groups, varying in severity of disease a significant differences in P-RNase and IL-6, IL-8 and sTNFR55/sTNFR75 were found. In patients with acute necrotizing pancreatitis P-RNase significantly correlate with levels of major inflammatory cytokines. Carried out studies suggest that activity of P-RNase reflects severity of inflammatory reaction, which is dependent on development of pancreatic injury and tissue necrosis in AP.