Study on adhesion formation and the healing of colon anastomosis in rats with induced peritoneal sepsis

Effects of metoclopramide on the expression of metalloproteinases and interleukins in left colonic anastomoses. An experimental study

PURPOSE

To evaluate the effects of metoclopramide on metalloproteinases (MMP) and interleukins (IL) gene expression in colonic anastomoses in rats.

METHODS

Eighty rats were divided into two groups for euthanasia on the 3rd or 7th postoperative day (POD), then into two subgroups for sepsis induction or not, and then into subgroups to receive either metoclopramide or saline solution. Left colonic anastomosis were performed and then analyzed.

RESULTS

On the 3rd POD, metoclopramide was associated with increased expression of MMP-1a, MMP-13, and TNF-α. On the 7th POD, the transcripts of all MMPs, TNF-α, IL-1β, IFN-γ, and IL-10 of the treated animals became negatively modulated. In the presence of sepsis, metoclopramide did not change MMPs and decreased IL-6, IL-1β, IFN-γ and IL-10 gene expression on the 3rd POD. On the 7th POD, increased expression of all MMPs, IFN-γ and IL-10 and negative modulated TNF-α and IL-6 gene expression.

CONCLUSION

Administration of metoclopramide increased metalloproteinases and interleukins gene expression on the 3rd postoperative day and negatively modulated them on the 7th POD. In the presence of abdominal sepsis, metoclopramide did not change MMPs and decreased ILs gene expression on the 3rd POD. On the 7th POD, the drug increased expression of all MMPs.

The Effect of Systemic Carnitine Administration on Colon Anastomosis Healing in an Experimental Sepsis Model

AIM

This study aimed to investigate the effects of L-carnitine, with its known antioxidant properties and positive effects on wound healing, on the healing of colon anastomosis in a cecal ligation and puncture sepsis model in rats.

MATERIALS AND METHODS

A total of 40 Sprague-Dawley rats were used. The rats were randomly divided into four groups of 10 (n = 10). Groups 1 and 2 had laparotomy and colon anastomosis performed. Groups 3 and 4 had cecal ligation and puncture (CLP) and colon anastomosis performed. Rats in Groups 1 and 3 were given 15 mL/kg intraperitoneal 0.9% isotonic NaCl, while the rats in Groups 2 and 4 were given 100 mg/kg intraperitoneal L-carnitine. On the postoperative fifth day, the rats were sacrificed and the burst pressure of anastomosis, histopathological effects, and tissue hydroxyproline levels were investigated.

RESULTS

In Groups 2 and 4, the anastomosis burst pressure and histopathological results in both noninfected abdomen and presence of peritonitis were statistically high compared to the control group (p < 0.05). Though the hydroxyproline levels were also high, there was no statistically significant difference for this parameter (p > 0.05).

CONCLUSIONS

The findings obtained from the experimental sepsis model showed that healing of anastomosis in both the presence of peritonitis and noninfected abdomen was positively affected by the systemic administration of L-carnitine and this may contribute to the safety of anastomosis.

Effects of bromopride on the healing of left colonic anastomoses in rats with induced abdominal sepsis

PURPOSE

To evaluate the effects of bromopride on the healing of left colonic anastomoses in rats with induced abdominal sepsis.

METHODS

Forty rats were divided into two groups to receive either bromopride (experimental group- E) or saline (control group- C). Each group was divided into subgroups of ten animals each to be euthanized on third (E3 and C3) or seventh day (E7 and C7) after surgery. Sepsis was induced by cecal ligation and puncture. The rats underwent segmental left colon resection and end-to-end anastomosis. Adhesion formation, tensile strength and hydroxyproline concentration were assessed. Histomorphometry of collagen and histopathological analysis were also performed.

RESULTS

On postoperative third day, anastomoses in bromopride-treated animals showed lower tensile strength (p=0.02) and greater reduction in hydroxyproline concentration (p=0.04) than in control animals. There was no statistical difference in these parameters on seventh day, and the remaining parameters were similar across subgroups. Collagen content was also similar across subgroups.

CONCLUSION

In the presence of abdominal sepsis, the administration of bromopride was associated with decreased tensile strength and hydroxyproline concentration in left colonic anastomoses in rats three days after surgery.

Expression of metalloproteinases and interleukins on anastomoses in septic rats

BACKGROUND

Anastomotic dehiscence is the most severe complication of colorectal surgery and its incidence increases in the presence of infection. It has been reported that immune factors or the activity of matrix metalloproteinases (MMP) may mediate the loss of anastomotic strength in the first postoperative days. In this study, we investigated the effects of abdominal sepsis on the MMP and interleukin (IL) gene expression in left colonic anastomoses in rats.

MATERIALS AND METHODS

Forty rats were divided into two groups of 20 animals according to the presence (group S) or absence (group N) of sepsis induction by cecal ligation and perforation during left colonic anastomosis. Each group was divided into subgroups for euthanasia on the third (N3 and S3) or seventh (N7 and S7) postoperative day (POD). A colonic segment containing anastomosis was removed for analysis of the expression of MMP1a, MMP8, MMP13, IL1β, IL6, IL10, TNFα, and IFNγ genes.

RESULTS

The anastomoses with abdominal sepsis showed increased MMP1a gene expression and decreased MMP8 gene expression both on the third and seventh POD. There was no change in the expression of MMP13. There was an increase in the expression of IL10 only on the third POD and a negative modulation of IL1β, IFNγ, and IL6 genes on both periods. The TNFα gene expression was negatively modulated on the third POD and became not modulated on the seventh POD.

CONCLUSION

Abdominal sepsis induced a specific inflammatory pattern with increased MMP1a and IL10 gene expression and negative modulation of MMP8, IL1β, IFNγ, and TNFα gene expression in left colonic anastomoses in rats.

Evaluation of the effects of S-methylisothiourea hemisulfate, an inducible nitric oxide synthase inhibitor, on the healing of colonic anastomosis in rats

PURPOSE

To evaluate the effects of S-methylisothiourea hemisulfate (SMT) on the healing of colonic anastomosis in rats.

METHODS

Sixty rats Wistar were distributed into two groups of 30 animals: experimental (E) and control C). The animals of experimental group received intraperitoneal SMT at 50 mg/kg/dose every 12 hours for 72 hours. The control group received intraperitoneal saline at the same volume of SMT. The rats were subdivided into subgroups groups of 10 for euthanasia on the third, seventh, and 14th postoperative days (POD). We evaluated clinical and weight evolution, breaking strength and histopathology; also, a blood sample was collected for serum dosage of nitrite/nitrate.

RESULTS

There was more vascular neoformation (p=0.006) and granulation (p=0.002) in the E3 group, and more mononuclear infiltrates in the C3 group (p=0.041). There was also more edema in the C14 group (p=0.008). There was no statistically significant difference in breaking strength, nitrite/nitrate dosage, and the remaining histopathological parameters.

CONCLUSION

The use of S-methylisothiourea hemisulfate improved the healing of colonic anastomosis in rats on the third postoperative day by accelerating the proliferative stage of healing, but without interfering with the breaking strength of the anastomosis.

Alcohol acute intoxication before sepsis impairs the wound healing of intestinal anastomosis: rat model of the abdominal trauma patient

Introduction

Most trauma patients are drunk at the time of injury. Up to 2% of traumatized patients develop sepsis, which considerably increases their mortality. Inadequate wound healing of the colonic repair can lead to postoperative complications such as leakage and sepsis.

Objective

To assess the effects of acute alcohol intoxication on colonic anastomosis wound healing in septic rats.

Methods

Thirty six Wistar rats were allocated into two groups: S (induction of sepsis) and AS (alcohol intake before sepsis induction). A colonic anastomosis was performed in all groups. After 1, 3 or 7 days the animals were killed. Weight variations, mortality rate, histopathology and tensile breaking strength of the colonic anastomosis were evaluated.

Results

There was an overall mortality of 4 animals (11.1%), three in the group AS (16.6%) and one in the S group (5.5%). Weight loss occurred in all groups. The colon anastomosis of the AS group didn’t gain strength from the first to the seventh postoperative day. On the histopathological analysis there were no differences in the deposition of collagen or fibroblasts between the groups AS and S.

Conclusion

Alcohol intake increased the mortality rate three times in septic animals. Acute alcohol intoxication delays the acquisition of tensile strength of colonic anastomosis in septic rats. Therefore, acute alcohol intoxication before sepsis leads to worse prognosis in animal models of the abdominal trauma patients.