Prostaglandin E1 maintains structural integrity of intestinal mucosa and prevents bacterial translocation during experimental obstructive jaundice

Effects of Prostaglandin E1 on Patients Undergoing Major Gastrointestinal Surgery

OBJECTIVE

The aim of this study was to investigate the clinical effects of prostaglandin E1 (PGE1) in patients who underwent surgery for gastrointestinal (GI) trauma, perforation, or obstruction.

BACKGROUND

PGE1 is thought to enhance intestinal blood supply and reduce GI complications during the postoperative period.

METHODS

The medical records of 889 patients undergoing major GI surgery were reviewed retrospectively. Propensity score matching was performed to adjust for any baseline differences. Clinical outcomes, including early GI function recovery, postoperative complications, and length of hospital stay, were evaluated in all patients. In 278 paired patients, selected nutritional, immunologic, and inflammatory variables were compared based on PGE1 administration.

RESULTS

After propensity score 1:1 matching, the baseline characteristics were similar for both groups. PGE1 was associated with prompt postoperative GI function recovery, including first bowel movement [2.6 ± 0.9 vs 3.1 ± 1.0 days after surgery in patients with and without PGE1 treatment, risk ratio 0.51, 95% confidence interval (CI) 0.41-0.65, P < 0.001] and first feeding within postoperative day 3 [179 (64.39%) vs 152 (54.68%); risk ratio 0.61, 95% CI 0.42-0.90, P = 0.012]. A lower overall postoperative complication rate, including infectious complications [45 (16.2%) vs 68 (24.5%); odds ratio 0.60, 95% CI 0.39-0.91, P = 0.010] and major complications [23 (8.3%) vs 48 (17.3%); odds ratio 0.43, 95% CI 0.26-0.73, P = 0.001], was noted in patients with PGE1 treatment than in patients without PGE1 treatment. Furthermore, the immunologic and inflammatory variable C-reactive protein on postoperative day 3 was reduced by PGE1 treatment (52.5 ± 36.4 vs 89.6 ± 42.4 mg/L; P = 0.037, t test).

CONCLUSIONS

PGE1 is associated with beneficial clinical effects, such as prompt postoperative GI function recovery and reduced overall postoperative complications after emergency GI surgery, which may be attributed to a reduced inflammatory response.

Protective Effects of Curcumin on Intestinal Damage in Cholestatic Rats

BACKGROUND

The aim of this study was to evaluate the possible protective effects of curcumin on oxidative stress, cell proliferation, and apoptosis in the rat intestinal mucosa after bile duct ligation (BDL).

METHODS

A total of 18 male Sprague Dawley rats were divided into three groups: sham control, BDL and BDL+curcumin; each group contain six animals. The rats in the curcumin-treated group were given curcumin (100 mg/kg) once a day orally for 14 days, starting 3 days prior to BDL operation. Following 14 days of treatment, all the animals were decapitated and intestinal tissues samples obtained for biochemical and histopathological investigation.

RESULTS

Curcumin treatment was found to significantly lower elevated tissue malondialdehyde levels and myeloperoxidase activity, and to raise reduced glutathione levels in intestinal tissues samples. BDL caused severe histopathological injury, including shortening of the villi, loss of villous epithelium, multiple erosions, inflammatory cell infiltration, necrosis, and hemorrhage into the intestinal wall. Curcumin treatment significantly attenuated the severity of intestinal injury, with inhibition of BDL-induced apoptosis and cell proliferation.

CONCLUSION

Curcumin treatment has a protective effect against intestinal damage induced by BDL. The ability of curcumin treatment is to inhibit BDL-induced oxidative stress, apoptosis, and cell proliferation.

The Effect of Curcumin on an Animal Intestinal Ischemia/Reperfusion Model for Bacterial Translocation and Inflammatory Response

Ischemia/reperfusion (IR) injury of the intestine is a major problem in abdominal pathological condition and is associated with a high morbidity and mortality. The purpose of the study is to investigate the effects of curcumin on the bacterial translocation incidence and inflammatory response in rats submitted to bowel ischemia reperfusion injury. Thirty-two Wistar albino rats with a weight of 200 to 250 g were used in the study. They were randomly divided into 3 groups (n = 10 for each group): sham only operated group(group I); IR group (group II); and IR + curcumin treatment group (group III). Curcumin (curcumin from Curcuma longa) 20 mg/kg/day was given orally to the curcumin group. All animals were given 109 E. Coli by orogastric intubation 12 hours before sampling. Seventy-two hours after the first operation, mesenteric lymph node and blood samples were obtained and cultured. Blood samples of 2 mL were obtained for a polymerase chain reaction study. A piece of terminal ileum was also sampled for histopathologic examination. Mesenteric lymph node and blood cultures of all control animals were positive for microbiological growth, and polymerase chain reaction results were positive in seven of the eight rats. Histopathologically, edema, vasodilatation and inflammatory cell infiltration were found to be less in the other groups in comparison to the control group. Curcumin reduced bacterial translocation in blood, hepatocellular damage, and plasma cytokine levels. Curcumin reduced the incidence of bacterial translocation in intestinal I/R. rats. These results suggest that Curcumin would be clinically useful in the treatment of intestinal I/R injury.

Time course of intestinal barrier function injury in a sodium taurocholate-induced severe acute pancreatitis in rat model

OBJECTIVE

The aims of this study were to clarify the kinetics of intestinal barrier function impairment in sodium taurocholate-induced severe acute pancreatitis (SAP) models and to explore an appropriate concentration of sodium taurocholate and a suitable time point for further study.

METHODS

In total, 104 rats were randomly divided into four groups: the normal control group (n = 8) receiving no treatment, the sham-operation group (n = 32), the 2.5% and 5% sodium taurocholate-treated SAP groups (n = 32 for each group) which were induced via a retrograde injection of 2.5% or 5% sodium taurocholate into the pancreatic duct. Histological examination, serum D-lactate and endotoxin levels and the incidence of bacteria translocation were recorded to assess the intestinal mucosal injury.

RESULTS

Pancreatitis models were successfully established in both the 2.5% and 5% sodium taurocholate-treated groups. The dosage of sodium taurocholate used to induce pancreatitis was positively correlated with the degree of intestinal mucosal injury. The most severe damage to intestinal barrier was observed 24 h after surgery in the 2.5% sodium taurocholate-treated group and 48 h after surgery in the 5% sodium taurocholate-treated group, respectively.

CONCLUSION

Based on the success rate of the model, the mortality and the impairment of intestinal barrier function, we conclude that 24 h after a retrograde injection of 2.5% sodium taurocholate may be the most appropriate time point to study intestinal barrier injury in SAP rats.

Effect of bile pigments on the compromised gut barrier function in a rat model of bile duct ligation

Background

Studies have shown that the absence of bile in the gut lumen, either by bile duct ligation or bile diversion, induces mucosal injury. However, the mechanism remains elusive. In this study, the role of bile pigments in gut barrier function was investigated in a rat model of bile duct ligation.

Methods

Male Sprague Dawley (SD) rats were used in this study. After ligation of bile duct, the animals were administrated with free bilirubin, bilirubin ditaurate, or biliverdin by intragastric gavage. 1, 2, or 3 days later, the animals were sacrificed and the damage of mucosa was assessed by histological staining as well as biochemical parameters such as changes of diamine oxidase (DAO) and D-lactate (D-Lac) in the blood. Trypsin and chymotrypsin of the gut were also measured to determine how these digestive proteases may relate to the observed effects of bile pigments.

Results

Bile duct ligation (BDL) caused significant increases in gut trypsin and chymotrypsin along with damage of the mucosa as demonstrated by the histological findings under microscope, the reduced expression of tight junction molecules like occludin, and significant changes in DAO and D-lac in the blood. Free bilirubin but not bilirubin ditaurate or biliverdin showed significant inhibitions on trypsin and chymotrypsin as well as alleviated changes of histological and biochemical parameters related to gut barrier disruption.

Conclusion

Bile may protect the gut from damage through inhibiting digestive proteases like trypsin and chymotrypsin by free bilirubin.

Berberine ameliorates severe acute pancreatitis‑induced intestinal barrier dysfunction via a myosin light chain phosphorylation‑dependent pathway

Berberine is a traditional drug used to treat gastrointestinal disorders in China and has been demonstrated to attenuate intestinal barrier dysfunction in certain animal models. However, the effects of berberine on pancreatitis-induced intestinal barrier dysfunction are yet to be fully elucidated. This study aimed to investigate the effect of berberine pretreatment on the attenuation of intestinal barrier dysfunction induced by severe acute pancreatitis (SAP). A total of 36 rats were randomly divided into Sham, SAP and SAP plus berberine groups. Pancreatitis was induced using retrograde injection of 3% Na-taurocholate into the pancreatic duct. Histological examinations of the pancreas were performed and intestinal barrier dysfunction was characterized by histological measurements and the assessment of serum diamine oxidase activity and endotoxin levels. Zonula occludens-1 and occludin mRNA and protein expression, as well as myosin light chain (MLC) phosphorylation, were assessed. SAP rat models were successfully established. Berberine treatment was found to have no significant effect on the histological changes in the pancreas, but was observed to ameliorate the intestinal mucosal barrier damage and membrane permeability associated with SAP. Although berberine exerted minimal effects on tight junction proteins in the ilea of SAP rats, it was observed to significantly inhibit SAP-induced MLC phosphorylation. To the best of our knowledge, this is the first study to demonstrate that berberine attenuates SAP‑induced intestinal barrier dysfunction in vivo. In addition, this study shows that the effect of berberine on intestinal barrier function may be associated with the inhibition of SAP‑induced upregulation of MLC phosphorylation.

Superiority of ceftriaxon to cefazolin in a rat model of obstructive jaundice: an experimental study

OBJECTIVE

The objective of this study was to evaluate the serum and bile concentrations of cefazolin and ceftriaxone at the third and sixth hours in an experimental obstructive jaundice model and to identify the rate of excretion of these antibiotics into the bile.

MATERIAL AND METHODS

Thirty-two Wistar albino rats were used in this study. The bile and serum levels of cefazolin were measured at the third hour in the A1 group and at the sixth hour in the A2 group, with cefazolin administered as 5 mg/rat; while the bile and serum levels of ceftriaxone were studied at the third hour in the B1 group and at the sixth hour in the B2 group, with ceftriaxone administered as 5 mg/rat.

RESULTS

After 3 hr of cefazolin administration, the serum concentration in the A1 group reached a mean of 1.8 μg/ml, while the bile concentration was 90% of the serum concentration, with a mean of 1.6 μg/ml; whereas in the B1 group, the third-hour serum concentration of ceftriaxone was 18.6 μg/ml, while the bile concentration was found to be as high as 330% of this level, i.e., 56 μg/ml. The serum value of cefazolin decreased to 1.4 μg/ml in the A2 group and ceftriaxone decreased to 3.7 μg/ml in the B2 group at the sixth hour.

CONCLUSIONS

Although the excretory level of cefazolin and ceftriaxone into the bile reaches therapeutic doses, the duration for which these levels are above those required for bactericidal activity is short. Ceftriaxone is better concentrated in the serum and bile than cefazolin.

Effect of melatonin and misoprostol on bacterial translocation in portal hypertensive rats

BACKGROUND AND AIM

Portal hypertension is the main complication of cirrhosis and it is responsible for its most common complications. Bacterial translocation increases the morbidity and mortality rates in patients with portal hypertension. We aimed to investigate the effects of melatonin and misoprostol on bacterial translocation induced by portal hypertension.

METHODS

We established four groups, each containing eight rats. Except for the control and sham groups, the animals in the other groups (treatment groups) received misoprostol or melatonin for 3 days after the first operation. In the sham group, a laparotomy was carried out and only the portal vein was dissected. Calibrated portal vein ligation was carried out in the other groups. All animals were given 10(10) Escherichia coli by orogastric intubation 12 h before sampling. Seventy-two hours after the first operation, mesenteric lymph node and blood samples were obtained and cultured. Two cc blood samples were obtained for a polymerase chain reaction study. A piece of terminal ileum was also sampled for histopathologic examination.

RESULTS

Mesenteric lymph node and blood cultures of all control animals were positive for microbiological growth, and polymerase chain reaction results were positive in seven of the eight rats. Histopathologically, edema, vasodilatation and inflammatory cell infiltration were found to be less in the other groups in comparison to the control group. The incidence of bacterial translocation was decreased in all treatment groups as compared to the control group.

CONCLUSIONS

In this study, bacterial translocation occurred in portal hypertension. Melatonin and misoprostol reduced the incidence of bacterial translocation in portal hypertensive rats.

Evidence for tight junction protein disruption in intestinal mucosa of malignant obstructive jaundice patients

OBJECTIVE

Experimental and clinical studies have shown that obstructive jaundice results in increased intestinal permeability. The mechanisms implicated in this phenomenon remain obscure. Integrated tight junctions (TJs) are essential for normal gut barrier function. TJ proteins, such as zonula occludens (ZO)-1, claudins and occludin, are indispensable to maintain the function of TJs. This study was undertaken to investigate whether TJ protein disruption occurs in the intestinal mucosa of malignant obstructive jaundice (MOJ) patients.

MATERIAL AND METHODS

Three groups were involved: Group A, MOJ patients whose bilirubin level was >or= 43 microM; Group B, MOJ patients without jaundice; and Group C, patients who underwent gastroscopy with negative findings (controls). Biopsy was done in all participants at the second part of the duodenum, distal to the ampulla of Vater. The morphological and ultrastructural changes of intestinal mucosa were observed. The distributions and expressions of the TJ proteins occludin, ZO-1, claudin-1 and claudin-4 in intestinal mucosa were evaluated by immunohistochemistry and Western blotting.

RESULTS

Histological examination showed a mild infiltration of the lamina propria by chronic inflammatory cells in Group A compared with Groups B and C. Duodenal architecture showed that the microvillus of Group A patients was loose, the structures of junctional complexes were disrupted and the gaps between cell junctions were wider. As shown by immunohistochemical staining and Western blotting, greatly reduced expressions of occludin, ZO-1 and claudin-1 protein were detected in Group A, whereas claudin-4 expression was significantly increased.

CONCLUSIONS

TJs in MOJ patients with jaundice were disrupted in the intestinal epithelium, which may have resulted from the alterations in TJ-related protein expression. TJ interruption may be a key factor contributing to intestinal mucosal barrier injury and increased intestinal permeability.

Protective effect and mechanisms of radix astragali injection on the intestinal mucosa of rats with obstructive jaundice

Objective. To research the protective effects and mechanisms of Radix Astragali injection on the intestinal mucosa of rats with obstructive jaundice (OJ). Methods. The rats were randomly divided into sham-operated, model control and Radix Astragali treated group. We observed the pathological changes of intestinal mucosa, expression levels of Bax and NF-κB proteins, and apoptosis indexes in intestinal mucosa as well as serum NO, MDA and SOD contents, respectively, on 7d, 14d, 21d and 28d after operation. Results. The pathological severity score (on 7d and 14d), apoptotic indexes (on 14d) of the intestinal mucosa and serum MDA content (on 14d) of treated group were significantly lower than those in the model control group (P < .05). The serum SOD contents (on all time points) of treated group were significantly higher than those in the model control group (P < .05). The sham-operated group (on 21d) of the product of staining intensity and positive rate of Bax protein was significantly lower than model control group (P < .05). Conclusion. Radix Astragali injection could protect the intestinal mucosa of OJ rats by increasing the content of SOD, reducing the content of MDA, inhibiting the apoptosis and relieving the pathological changes of intestinal mucosa.

Acute pancreatitis, bacterial translocation, and different octreotide regimens: an experimental study

PURPOSE

To determine the effect of octreotide, octreotide with zinc, levamisole, and misoprostol on the bacterial translocation that develops in rats with acute pancreatitis (AP).

METHODS

A total of 36 rats were divided into six groups, each consisting of six rats. Only laparotomy was performed on the first group. Acute pancreatitis was performed on the second group. Octreotide was given to the third, fourth, fifth, and sixth groups. Octreotide, octreotide with zinc, levamisole, and misoprostol were given to groups III, IV, V, VI, respectively. Rats were euthanized 48 h after the occurrence of AP. Blood and mesenteric lymph node samples were collected for polymerase chain reaction (PCR). Pancreatic tissue and terminal ileum were obtained for histopathological examinations.

RESULTS

The severity of pancreatitis and mucosal damage of the terminal ileum was higher in group II than groups I, III, IV, V, and VI, histopathologically (P < 0.05). There wasn't a significant difference with respect to OA with Zn or L or M and OA group (P > 0.05). A significant difference was found in PCR positivity in blood and mesenteric lymph node between groups I and II (P < 0.05).

CONCLUSIONS

In AP, administering octreotide alone significantly prevented the bacterial translocation by preventing mucosal damage. The zinc, levamisole, or misoprostol with octreotide did not influence the results.