Protection against ischemia/reperfusion injury by the cavitary two-layer method in canine small intestinal transplantation with reduction of reactive oxygen species

Sufentanil inhibits the metastasis and immune response of breast cancer via mediating the NF-κB pathway

OBJECTIVE

Breast cancer (BC) causes cancer-related death in women. Sufentanil is used for cancer pain and postoperative analgesia. This study aimed to explore the role of sufentanil in BC.

METHODS

BC cells were treated with sufentanil, and cell viability was evaluated using the cell counting kit-8 (CCK-8) assay. Biological behaviors were analyzed using EDU assay, flow cytometry, transwell assay, western blotting, and ELISA. The levels of NF-κB pathway-related factors were examined using western blotting. A xenograft tumor model was established to assess the effects of sufentanil on tumor growth in vivo.

RESULTS

Sufentanil at the concentration of 20, 40, 80, and 160 nM suppressed cell viability (IC50 = 39.84 in MDA-MB-231 cells, and IC50 = 47.46 in BT549 cells). Sufentanil inhibited the proliferation, invasion, epithelial-mesenchymal transition (EMT), and inflammation, but induced apoptosis of BC cells. Mechanically, sufentanil suppressed the activation of the NF-κB pathway. Rescue experiments showed that RANKL (NF-κB receptor agonist) abrogated the effects induced by sufentanil. Moreover, sufentanil inhibited tumor growth, inflammatory response, but promoted apoptosis via the NF-κB pathway in vivo.

CONCLUSIONS

Sufentanil decelerated the progression of BC by regulating the NF-κB pathway, suggesting sufentanil may be used in BC therapy.

Normothermic extracorporeal membrane oxygenation support: Improving the function of intestinal grafts obtained from cardiac death donors

Extracorporeal membrane oxygenation (ECMO) could ameliorate the energy status and viability of bowel grafts from cardiac death donors. However, the function of these grafts after transplantation is not clear. The purpose of the study was to evaluate the early function of intestinal grafts after transplantation from expected cardiac death donors supported with normothermic extracorporeal support using a porcine allogeneic orthotopic segmental small bowel transplantation model. Eighteen domestic crossbred donor pigs were assigned to living donation (LD), donation after cardiac death (DCD), and ECMO groups. In the LD group, small bowels were harvested and preserved immediately in cold storage. In the other two groups, the donor pigs received conventional rapid recovery treatment or 1-hour normothermic extracorporeal support after 10-minutes expected cardiac arrest. Subsequently, the small bowels were removed and preserved in cold storage. After 5-6 hours of preservation, small bowel grafts were transplanted into the recipient pigs that underwent enterectomy. The pathology and electron microscopy results, cell apoptosis rate, tight junction protein expression level in the intestinal mucosa, and plasma endotoxin level were evaluated after transplantation. All grafts functioned on the basis of the maltose absorption test results at day 7 after transplantation. There were no significant differences in the morphological changes in the intestinal mucosa among the three groups at day 7 after transplantation. The cell apoptosis rate and plasma endotoxin level in the ECMO group did not differ significantly than those in the LD group, but were evidently lower than those in the DCD group (P < .001). The intestinal absorptive function improved significantly in the ECMO group in contrast with that in the DCD group (P < .001). Short-term ECMO intervention can alleviate ischemia-reperfusion injuries in intestinal grafts and improve intestinal absorptive function in the early stage after transplantation. Reducing caspase-3 protein expression and cell apoptosis in the intestinal mucosa may be one of the protective mechanisms of ECMO intervention.

Intestinal Conditioning After Cardiac Arrest: The Use of Normothermic Extracorporeal Membrane Oxygenation in the Non-Heart-Beating Animal Model

The effect of normothermic extracorporeal membrane oxygenation (NECMO) on small bowel preservation in a clinically relevant large animal model of expected donation after cardiac death (eDCD) was evaluated. Thirty domestic crossbred donor pigs were divided into five groups. The first group served as the live donation (LD) group, the second group served as the donation after cardiac death (DCD) group, and the remaining were further assigned into three subgroups: E1 group (1 h NECMO support), E3 group (3 h NECMO support), and E5 group (5 h NECMO support). Pathology, electron microscopy, energy metabolism, cell apoptosis, and tight junction (TJ) protein expression level of intestinal mucosa and the level of plasma d-lactic acid were evaluated in normal, cardiac death and at the end of extracorporeal support, respectively. The mean arterial pressure and PaO2 were maintained over 60 and 267 mm Hg during NECMO support, respectively. One hour of extracorporeal support could improve the energy status in intestines of the DCD group. Although the histologic damage and apoptosis of the E1 group had no significant difference with those of the LD and DCD groups (P > 0.05), the levels of intestinal mucosa TJ protein decreased (P < 0.05), and plasma d-lactic acid increased progressively (P < 0.05). With the extension of extracorporeal support, the degree of intestinal mucosa damage and intestinal permeability gradually increased, as well as the content of adenosine triphosphate in intestinal mucosa. The normothermic extracorporeal support for 1 h in DCD is beneficial for improving the energy status and viability of the bowel. However, the integrity of intestinal mucosa was destroyed gradually as extracorporeal support time went by. And the activation of intestinal epithelial apoptosis and hyperoxia might be the factors that lead to intestinal mucosa injury.

Lifor Solution: An Alternative Preservation Solution in Small Bowel Transplantation

Background and Objectives. The intestinal mucosa is extremely sensitive to ischemia. Better intestinal preservation is the first step to improve the results of intestinal transplantation. The aim of the study is to investigate the effect of cold Lifor solution on preservation of swine small bowel. Methods. Swine ileum segments (200 cm) were allotransplanted heterotopically after 9-hour cold storage with UW solution (group 1, n = 6), with Lifor solution (group 2, n = 6), or without storage (group 3, n = 6), respectively. After cold storage, mucosal adenosine triphosphate (ATP) concentrations and histopathologic analysis after preservation were performed. At day 7 after the transplantation, intestinal absorptive function was also observed. Results. After 9 h cold preservation, pathological changes, the content of ATP in the intestinal mucosa, and the intestinal absorptive function after transplantation in group 2 were similar to those of group 1. Conclusion. The effect of cold storage of swine small bowel with Lifor solution is similar to that of UW solution. It may provide additional rationale for further exploration of Lifor as an alternative preservation solution in small bowel transplantation.

Organ-specific solutions and strategies for the intestinal preservation

Among the intraabdominal organs, the intestine is the most susceptible to storage injury and as a consequence its safe cold ischemic time in the clinic is restricted to below 10 hours. The current practice for the intestinal preservation (IP) consists of an in-situ vascular flush with iced University of Wisconsin or Histidine-Tryptophan-Ketoglutarate solution followed by cold storage at 4°C. Mucosal injury is initiated within 1 hour and rapidly progresses to mucosal breakdown; tissue injury worsens upon reperfusion and further impairs the mucosal barrier, favoring bacterial translocation and sepsis. In addition of releasing danger signals, an advanced ischemia-reperfusion injury (IRI) may increase graft immunogenicity and promote rejection. Several alternative approaches have been tested as alternatives to the static storage. The aim of this review is to summarize and discuss the various intraluminal interventions as additional strategies aiming to reduce the IP/reperfusion injury and highlight the underlying pathophysiological mechanisms.

Effect of hyperbarically oxygenated-perfluorochemical with University of Wisconsin solution on preservation of rat small intestine using an original pressure-resistant portable apparatus

BACKGROUND

Perfluorochemicals (PFC) are chemical substances that have a higher oxygen solubility under hyperbaric oxygen (HBO) pressure. This study investigated the effect of cold HBO-PFC/University of Wisconsin (UW) solution on preservation of rat small intestinal graft.

METHODS

We manufactured an air-tight, pressure-resistant tank made of stainless steel with high thermal conductivity. Rat ileal grafts were placed in a custom-made silicon-gum bag with UW solution, which was immersed in 5 atm HBO-PFC solution in the tank (Group P-5). The tank was kept at 4 degrees C. We compared the ATP concentration and mucosal permeability in Group P-5 with grafts preserved in 1 atm oxygenated-PFC/UW solution (Group P-1) and simple cold storage in UW solution (Group C). Histologic study was also performed.

RESULTS

PO(2) in UW solution after 48 h preservation were 1852 +/- 37, 499 +/- 13, and 173 +/- 3 mmHg (Group P-5, P-1 and C, respectively, mean +/- SD). At 48 h of preservation, graft ATP concentration was significantly greater in Group P-5 compared to that in Group P-1 and Group C. Mucosal hyperpermeability as well as mucosal morphologic changes were also ameliorated in Group P-5.

CONCLUSION

HBO-PFC can supply a greater amount of oxygen to UW solution. Indirect measures of oxygen metabolism such as ATP content and lactate production suggested improvement in maintaining graft oxygen metabolism.

Metabolic, Coagulative, and Hemodynamic Changes During Intestinal Transplant: Good Predictors of Postoperative Damage?

BACKGROUND

Analysis of intraoperative changes of metabolic, hemodynamic, and coagulative parameters is useful to detect early ischemia-reperfusion damage after intestinal transplant.

METHODS

The objective of our study is to correlate the histological damage at the end of transplant in relation to the intraoperative changes after reperfusion. The histological aspect was graded according to Park's classification at the end of the surgical procedure with biopsies of the graft. Patients were divided into two groups according to the presence or absence of histological damage of the small bowel wall: group A (normal mucosa/minimal damage: Park's grades 0-1) and group B (mucosal damage: Park's grades 2-8).

RESULTS

Significant hemodynamic, metabolic, and coagulative disorders were observed in group B. Consequently, these disorders are thought to be early indicators of graft damage.

CONCLUSIONS

Actual monitoring procedures used for postoperative graft surveillance remain paramount in detecting postoperative intestinal dysfunction, but the indicators described in this paper could represent a further help in intraoperative and postoperative management.

Antitumor Effect of Gemcitabine on Orthotopically Inoculated Human Gallbladder Cancer Cells in Nude Mice

BACKGROUND

The prognosis of gallbladder carcinoma is poor; therefore, investigating the efficacy of new chemotherapy agents is essential for the treatments for this tumor. Recently, several studies have reported clinical trials using gemcitabine as treatment for advanced gallbladder cancers. However, the antitumor effects of gemcitabine on gallbladder carcinoma have not been examined in in vitro and in vivo model systems.

METHODS

We examined the cytotoxicity of gemcitabine in four biliary tract cancer cell lines using the WST-1 assay. In addition, we examined the effect of gemcitabine on gallbladder cancers resulting from orthotopic inoculation of NOZ gallbladder tumor cells into nude mice. One week after transplantation, the mice were randomized into two groups: In Group A, the mice were treated by an intra-peritoneal injection of 0.9% sodium chloride for three weeks after inoculation (control). In Group B, the mice were treated by an intra-peritoneal injection of gemcitabine (125 mg / kg) for three weeks. All mice were sacrificed one week after the end of treatment, and macroscopic and histological findings were evaluated. The expression levels of proliferating-cell nuclear antigen (PCNA) were examined to investigate cellular proliferation activity, and Tunnel assays were performed to determine apoptotic status. Survival duration of the mice after gemcitabine treatment was compared to that of untreated mice.

RESULTS

The gemcitabine sensitivity of the four biliary tract cancer cell lines was similar in a dose dependent manner. In the in vivo models, the Group A mice showed huge tumors of the gallbladder, with liver invasion and lymph node metastases. However, there were no abdominal tumors in the Group B mice, and microscopic gallbladder cancer could only be detected from histological findings. The mean percent of PCNA-positive tumor cells was significantly higher in tumors from mice in Group A (71.9%) compared to those of Group B (34.7%). The mean percent of Tunnel-positive tumor cells was significantly lower in mice from Group A (2.0%) than those from Group B (5.7%). Survival duration was prolonged significantly in the gemcitabine-treated mice relative to untreated mice.

CONCLUSIONS

Gemcitabine treatment may inhibit tumor progression and prolong survival in gallbladder cancer by inhibiting cell proliferation and inducing apoptosis.

Molecular markers in stored kidneys using perfluorocarbon-based preservation solution: preliminary results

BACKGROUND

Delayed graft function (DGF) is a problem in kidney transplantation and cold ischemia has been identified as a risk factor. Perfluorocarbons (PFC) have an enhanced ability to dissolve and release oxygen. We evaluated histologically and a number of molecular changes induced by ischemia in stored kidneys with University of Wisconsin (UW) and PFC-based preservation solutions (PFC-UW).

MATERIALS AND METHODS

ACI rats were used as kidney donors. UW (control group) or PFC-UW (study group) preservation solutions were used for kidney perfusion. All kidneys were stored at 4 degrees C for 12, 24, and 36 hours. After this time, intragraft histologic evaluation as well as mRNA HO-1 and iNOS levels were also analyzed.

RESULTS

In the kidneys stored at 24 hours, mRNA HO-1 levels were elevated in the study group when compared with the control and mRNA iNOS was decreased.

CONCLUSION

We observed overexpression of HO-1 and underexpression of iNOS in the kidney tissue stored with PFC-UW solution at 24 hours. These preliminary data suggest that increasing oxygen delivery by PFC added to the perfusion solution triggers cytoprotective mechanism in kidney transplantation.

A Novel System for Organ and Tissues Preservation: The Refrigerating Hyperbaric Chamber

This study was designed to investigate the feasibility of building a simple and inexpensive device to preserve organs or tissues in hyperbaric and hypothermic conditions.

METHODS

The device was built on a 40-cm wide, 28-cm long, and 23-cm deep stainless steel chassis. The pressure vessel was built by a 7.8-cm bore stainless steel cylinder put inside another 12-cm cylinder welded together and closed by a steel plate on the top and bottom. The inferior plate was welded, and the superior one was fixed by manual clasp nut. The cooling system is made up of air compressor, condenser, expansion area, and cooling worm that is located between the cylinders. The temperature-controlling device is a computer processor contained in an integrated-circuit chip, with a on-off system to maintain the chamber temperature between 2 degrees to 4 degrees C. The compression of the chamber is performed by lateral coupling with the oxygen cylinder and is maintained at 5.5 absolute atmospheres and controlled by air pressure gauge. The maximal work pressure was evaluated by spreadsheet. Temperature or pressure changes were evaluated by 12- and 24-hour assays.

RESULTS

The maximal work pressure permitted was 6.5 absolute atmospheres. Thus, the container was free from danger. The temperature inside the chamber was kept between 2 degrees and 4 degrees C. The production costs of the prototype was US$1000.

DISCUSSION

The manufacture of the refrigerating hyperbaric chamber is viable, simple, and inexpensive.

Successful 40-hour preservation of the canine small intestine with the cavitary 2-layer method with glutamine supplementation

BACKGROUND

We recently reported that the cavitary 2-layer method (cTLM) allowed stable 24-hour preservation of canine intestine. The aim of this study was to examine the possibility of the 40-hour preservation by cTLM that is supplemented with glutamine.

METHODS

Canine jejunal segments (40 cm) were allotransplanted heterotopically without storage (group 1), after 40-hour cold storage with University of Wisconsin solution (group 2), cTLM (group 3), UW with 2% glutamine (group 4), or cTLM with 2% glutamine (group 5). Mucosal glutamine, histidine, tryptophan, glutathione, and adenosine triphosphate concentrations were determined immediately after preservation. At day 7 after the transplantation, maltose absorption test and histopathologic analysis were performed.

RESULTS

Mucosal glutamine concentrations increased significantly with glutamine supplementation during preservation in groups 4 and 5 (P < .01). Mucosal adenosine triphosphate levels in cTLM groups (groups 3 and 5) were similar to those in group 1; group 4 showed very low levels after preservation, despite glutamine supplementation. Mucosal glutathione did not differ among groups 2, 3, 4, and 5 and were significantly lower than in group 1. In the absorption test, serum glucose curves showed a peak level by 30 minutes in groups 1 and 5; delayed peaks were seen in groups 2, 3, and 4 compared with group 1. The villous heights were 879, 555, 685, 688, and 773 microm in groups 1, 2, 3, 4, and 5, respectively (group 1 vs group 2, 3, and 4: P < .05).

CONCLUSION

cTLM that was supplemented with glutamine extended a safe preservation period up to 40 hours in canine segmental small intestinal transplantation, although this study failed to elucidate a precise mechanism of the glutamine beneficial effect on the graft mucosa.

Preoperative bombesin administration can protect the rat small bowel allograft from ischemic reperfusion injury

BACKGROUND/PURPOSE

Ischemic reperfusion injury (IR/I) should be minimum for the success of small bowel transplantation (SBTx). This study investigated whether preoperative administration of neuropeptide bombesin (BBS) had a protective effect against IR/I and subsequent acute rejection.

METHODS

Allogenic SBTx was performed heterotopically in rats (n = 18). All rats were administered FK506 (0.32 mg/kg per day) everyday. The rats were divided into 3 groups of 6 rats each: group 1, BBS(-)5: warm ischemic time (WIT), 5 minutes without BBS; group 2, BBS(-)15: WIT, 15 minutes without BBS; group 3, BBS(+)15: WIT, 15 minutes with BBS. The specimens were obtained from the stoma site at 1 hour after reperfusion and on postoperative day (POD) 1 and 7. The graft mucosal state and degree of acute rejection were evaluated by H&E staining. The apoptotic cells in the crypt lesion was evaluated using terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling immunohistochemistry. Apoptotic index (AI) was calculated for quantitative analysis.

RESULTS

H&E staining revealed that the mucosal villi on POD 1 remained shortened in the BBS(-)15 group than in the other two groups. One hour after reperfusion, the AI in the BBS(-)15 group was 145.0 per thousand +/- 37.2 per thousand, which was significantly higher (P < .05) than in the BBS(-)5 group (32.6 per thousand +/- 5.0 per thousand) or the BBS(+)15 group (32.0 per thousand +/- 3.0 per thousand). On POD 7, the AI in the BBS(-)15 group was 63.7 per thousand +/- 5.03 per thousand, which was significantly higher (P < .05) than in the BBS(-)5 (17.3 per thousand +/- 4.6 per thousand) or the BBS(+)15 group (12.3 per thousand +/- 3.06 per thousand).

CONCLUSIONS

Even a short WIT of 15 minutes induced considerable allograft mucosal damage, which also worsened acute rejection. Exogenous BBS could prevent mucosal damage by IR/I and was also beneficial for the prevention of acute rejection.

Detailed analysis of mucosal restoration of the small intestine after the cavitary two-layer cold storage method

Small bowel transplantation (SBT) is associated with a high incidence of infectious complications because of ischemia/reperfusion (I/R) mucosal injury concomitant with potent immunosuppression. In this study, we evaluated whether the cavitary two-layer method (cTLM) could reduce I/R injury and allow early mucosal restoration, particularly after prolonged preservation and transplantation. Canine heterotopic segmental SBT was performed immediately without preservation (group 1), after 24-h preservation in UW solution (group 2) or by the cTLM (group 3). The graft samples were taken 1 h after reperfusion and on days 1, 4 and 7. We assessed graft mucosa with detailed microscopic and electromicroscopic analyses. In Group 3, histological injury and cell apoptosis after transplantation were significantly alleviated and rapidly recovered to a similar level of group 1. The mucosal restoration was morphologically completed within 4 days. In contrast, in group 2, more pronounced mucosal injury and delayed recovery were noted. Crypt cell proliferation activity was well maintained in groups 1 and 3 throughout the experimental period. Our ultrastructural analysis suggested that mitochondrial integrity achieved by the cTLM was a basal mechanism under the prompt mucosal restoration. The cTLM could reduce I/R injury, facilitate mucosal regeneration and restore the nearly normal structure early after SBT.