The Protective Effect of Nutraceuticals on Hepatic Ischemia-Reperfusion Injury in Wistar Rats

Nutraceuticals are bioactive compounds present in foods, utilized to ameliorate health, prevent diseases, and support the proper functioning of the human body. They have gained attention due to their ability to hit multiple targets and act as antioxidants, anti-inflammatory agents, and modulators of immune response and cell death. Therefore, nutraceuticals are being studied to prevent and treat liver ischemia-reperfusion injury (IRI). This study evaluated the effect of a nutraceutical solution formed by resveratrol, quercetin, omega-3 fatty acid, selenium, ginger, avocado, leucine, and niacin on liver IRI. IRI was performed with 60 min of ischemia and 4 h of reperfusion in male Wistar rats. Afterward, the animals were euthanized to study hepatocellular injury, cytokines, oxidative stress, gene expression of apoptosis-related genes, TNF-α and caspase-3 proteins, and histology. Our results show that the nutraceutical solution was able to decrease apoptosis and histologic injury. The suggested mechanisms of action are a reduction in gene expression and the caspase-3 protein and a reduction in the TNF-α protein in liver tissue. The nutraceutical solution was unable to decrease transaminases and cytokines. These findings suggest that the nutraceuticals used favored the protection of hepatocytes, and their combination represents a promising therapeutic proposal against liver IRI.

Septuagenarian Donors and Recipients in Deceased Donor Liver Transplantation: A Brazilian Single Center Experience and Literature Review

BACKGROUND

The number of elderly patients who have end-stage liver disease and require liver transplantation has dramatically increased. On the other hand, liver grafts from elderly donors have been offered more frequently for transplantation. The present study aims to analyze the results of liver transplants performed with donors and recipients aged ≥70 years.

METHODS

We performed a single-center retrospective study of deceased donors liver transplants that involved recipients aged ≥7070 years or recipients who received grafts from donors aged ≥70 years from 2011 to 2021. A literature review on the results of liver transplantation in elderly recipients was also performed.

RESULTS

Thirty septuagenarian recipients were included; their overall 1- and 5-years survival was 80% and 76.6%, respectively. The prevalence of recipients aged ≥70 years in our department was 2.65%. Twenty recipients received grafts form septuagenarian donors; their overall 1- and 5-years survival was 75%. The prevalence of donors aged ≥70 years in our department was 1%. In the literature review, 17 articles were analyzed. The 5-years survival of recipients aged ≥70 years ranged from 47.1% to 78.5%.

CONCLUSIONS

Septuagenarian recipients and patients who received grafts from elderly brain-dead donors present adequate overall survival after liver transplantation. Optimized donor-recipient matching is paramount for achieving good outcomes. The combination of high-risk donors with septuagenarian recipients should be avoided as well as using grafts of elderly donors that present others risk factors. Thus, the age of the donor or recipient alone cannot be considered an absolute contraindication for liver transplantation.

Hepatic Venous Outflow Obstruction in Adult Deceased Donor Liver Transplantation: Classic Piggyback Implantation Versus a Modified Technique that Widens the Ostium of the Recipient's Left and Middle Hepatic Veins

BACKGROUND

The classic piggyback technique uses the union of the 3 hepatic veins to perform the cavo-caval anastomosis. However, due to the lateral localization of the right hepatic vein, the partial clamping of the vena cava in this technique significantly reduces the venous return to the right atrium. To avoid this, we adopted in 2015 a modified piggyback technique, in which we use the common trunk of the middle and left hepatic veins and also perform a lateral incision toward the right in the anterior wall of the vena cava in order to widen the final ostium of the cavo-caval anastomosis. The aim of the study was to analyze the incidence of hepatic venous outflow obstruction between those 2 techniques.

METHODS

Retrospective study of liver transplant recipients undergoing venography for suspected hepatic venous outflow obstruction from January 2009 to June 2021. Patients undergoing transplantation with living donors or split grafts and pediatric cases were excluded from the study.

RESULTS

From January 2009 to December 2014 and from January 2015 to June 2021, 587 (group 1) and 730 (group 2) deceased-donor liver transplants were performed with the classic and the modified piggyback techniques, respectively. The incidence of cases with suspected hepatic venous outflow obstruction in groups 1 and 2 were 1.87% (n = 11) and 0.95% (n = 7), respectively (P = 0,15). The number of confirmed patients with outflow blockage that required endovascular treatment during venography in groups 1 and 2 were 4 (0.68%) and 5 (0.68%), respectively (P = 0,31).

CONCLUSIONS

This modified piggyback technique did not increase the incidence of hepatic venous outflow obstruction at our service.

Feasibility of Large Liver Grafts in Adults

INTRODUCTION

Size mismatch between donor and recipients may negatively influence postoperative results of liver transplantation (LT). In deceased donor LT for adults, large grafts are occasionally rejected due to the fear of primary nonfunction. The aim of this study is to assess the feasibility of using large liver grafts in adults undergoing deceased donor LT.

METHODS

We performed a retrospective study including adult patients who underwent deceased donor LT at our center between January 2006 and September 2019. Recipients with donors aged less than 18 years and those receiving split-liver grafts were excluded. Graft weight of 1800 grams was the cutoff used to divide patients in 2 groups: group 1 (graft weighing < 1800 g) and group 2 (grafts weighing ≥ 1800 g).

RESULTS

A total of 806 patients were included in the study. group 1 and 2 included 722 and 84 recipients, respectively. A larger proportion of male recipients was obseved in group 2: 64.8% vs 76.2% (P = .0037). Mean graft weight in group 1 and 2 was, respectively, 1348 ± 231.81 g and 1986.57 ± 165.51 g (P < .001), which resulted in significantly higher graft weight/recipient weight ratio and graft weight/standard liver volume ratio in group 2. In group 2, there were 9 (10.71%) patients with portal vein thrombosis as well as 24 patients (28.5%) with bulky ascites and 44 grafts (52.3%) with steatosis. Primary closure of the abdominal wall was not possible in 5 patients (5.9%) from this group. Primary nonfunction was diagnosed in 14 cases (16.6%), with liver retransplantation being performed in 6 of them. Male to female sex combination occurred in 19% of LT in group 2.

CONCLUSION

The use of large grafts is feasible; however, proper matching between donor and recipient is paramount, especially taking into consideration graft steatosis, portal vein thrombosis and the presence of bulky ascites.

Novel Technique in a Sheep Model of Uterine Transplantation

INTRODUCTION

Uterine transplantation (UTx) is a surgical therapeutic modality designed for the treatment of patients with exclusive uterine factor infertility. Experimental models are paramount to study this transplant modality, and as the ewes' uteri are very similar to that of humans, they are frequently used with this purpose. The aim of this study is to describe a novel technical variation for UTx in sheep.

METHODS

This study was conducted at Laboratory of Medical Investigation 37 of the University of São Paulo School of Medicine in São Paulo, Brazil, and was approved by the Ethics Committee of Animal Use of the university. We used 3 adult female sheep that weighed approximately 45 kg and were not pregnant. We performed the technique of uterine autotransplantation with a novel technical variation that we called sequential vascularization: first, we performed the right uterine artery and vein anastomoses, after which the uterine graft was vascularized, and then the contralateral vascular anastomoses were performed.

CONCLUSION

We described 3 successful uterine autotransplants in sheep models with sequential vascularization. This variation technique will probably allow warm ischemia time in UTx to significantly decrease.

Intraoperative Temporary Portocaval Shunt in Liver Transplant

BACKGROUND

Intraoperative temporary portocaval shunt (TPCS) has been performed during liver transplant to improve hemodynamics and renal function as well as to decrease bleeding during hepatectomy. The aim of this study was to evaluate the impact of TPCS on liver transplant in a long-term single-center study.

METHODS

From January 2006 to December 2018, all deceased donor transplants were retrospectively evaluated. Patients were divided in 2 groups: group 1, including those in whom intraoperative TPCS was performed and group 2, including those without TPCS. We analyzed recipient characteristics, survival, mortality, and complication rates in the intraoperative and postoperative periods.

RESULTS

A total of 999 deceased donor liver transplants were studied, with 509 patients in group 1 and 490 in group 2. There were 156 cases (15.61%) of preoperative portal vein thrombosis in the whole series. Postoperative renal function (P = .029) as well as length of hospital and intensive care unit stay (P = .0001) were better in group 1. Surgery time and warm ischemia time was also shorter in group 1 (P = .0001). Complications with Clavien-Dindo score ≥ 3 were higher in group 2 (P = .006). Multivariate analysis showed important risk with fulminant hepatitis (odds ratio, 2.127; 95% CI, 1.408-3.213; P < .0001) and Model for End-Stage Liver Disease > 29 (odds ratio, 2.492; 95% CI, 1.862-3.336; P < .0001). Overall survival in group 1 at 1, 5, and 10 years were 78%, 70%, and 68%, respectively. In group 2, they were 70%, 60%, and 58%, respectively (P = .027).

CONCLUSIONS

Patients who underwent intraoperative TPCS presented better postoperative renal function, less intraoperative blending, shorter surgical and warm ischemia time, shorter length of hospital and intensive care unit stay, and better overall survival after transplant. Moreover, TPCS should be used patients with severe conditions, such as fulminant hepatitis and Model for End-Stage Liver Disease score > 29.

Adult-to-Adult Living Donor Liver Transplant: Hemodynamic Evaluation, Prognosis, and Recipient Selection

BACKGROUND

Living donor liver transplant (LDLT) is a well-established treatment for end-stage liver disease. A better recipient selection and hemodynamic evaluation may improve transplant outcomes. The aim of this study was to establish recipient parameters that could enhance the results of adult-to-adult LDLT.

METHODS

We performed a retrospective study of all adult-to-adult LDLTs from a single center between January 2006 and December 2018. Variables analyzed included demographic and clinical parameters, laboratory tests, performance of intraoperative temporary portocaval shunt (TPCS), graft weight/recipient weight ratio (GW/RW), preoperative portal vein thrombosis (PVT), previous major abdominal surgery, and patient survival. Patients were divided in 2 groups according to GW/RW (0.8% cutoff point).

RESULTS

A total of 92 adult-to-adult LDLTs were analyzed, encompassing 53 male patients (57.6%). Mean Model for End-Stage Liver Disease score was 13.97 (SD, 4.74), and 57 patients (61.95%) had Child-Pugh-Turcotte score B. Mean GW/RW was 1.1% (SD, 0.37%). Group 1 with GW/RW > 0.8% (n = 74) and group 2 with it ≤ 0.8% (n = 13) presented mean GW/RW of 1.14% (SD, 0.24%) and 0.69% (SD, 0.09%) and P < .01, respectively. Eighteen patients (19.56%) presented PVT, with a worse survival than those without PVT (P = .006). Sixteen patients (17.39%) with previous major abdominal or biliary operations also presented higher mortality (P = .341). Forty-six (50%) intraoperative TPCSs were performed with a better 1- and 3-year patient survival. Receiver operating characteristic curve analysis showed PVT area under the curve of 0.701 (95% CI, 0.526-0.876; P = .018), positive predictive value of 0.69, and negative predictive value of 0.62. Multivariate analysis showed important risk regarding PVT (odds ratio, 6.160; 95% CI, 1.566-24.223; P = .004) and retransplant (odds ratio, 4.452; 95% CI, 0.843-23.503; P = .06).

CONCLUSIONS

Better recipient selection without PVT or previous major abdominal surgery, an adequate GW/RW, and intraoperative TPCS with hemodynamic modulation significantly improve outcomes of adult-to-adult LDLT.

Histopathologic Evaluation of Acute on Chronic Liver Failure

BACKGROUND

Currently, the diagnosis of acute on chronic liver failure (ACLF) is clinical, and its early identification and proper management are essential for a better prognosis. The aim of this study was to identify histopathologic parameters by analyzing cirrhotic liver explants that could aid in the early recognition of this entity and to determine prognostic factors that would influence ACLF management.

METHOD

We performed a retrospective analysis of histopathologic material from liver explants from patients transplanted because of chronic hepatitis C virus infection from January 2007 to July 2017. Twenty-nine (n = 29) cases without hepatocellular carcinoma were selected. Histopathologic analysis included the Laennec classification, vascularization, and portal vein thrombosis.

RESULTS

According to the diagnosis of ACLF, patients were divided in 2 groups: group ACLF (n = 10) and group no acute on chronic liver failure (NO-ACLF) (n = 19). Considering the whole series, mean age was 51 ± 11.48 years and prevalence of men was 58.62%. The mean Model of End-Stage Liver Disease (MELD) score at time of transplantation was significantly higher in the ACLF group than in the NO-ACLF group (35 ± 7 vs 22 ± 6, respectively, P < .05) as was the mean total bilirubin (14.38 ± 13.31 vs 8.84 ± 10.46 mg/dl, respectively, P < .05). Histopathologic analysis of explanted livers according to Laennec staging system of cirrhosis was as follows: 1. Group NO-ACLF: 1 case (5.25%) grade 3, 6 cases (31.58%) grade 4B, and 12 cases (63.16%) grade 4C; and 2. Group ACLF: 4 cases (40%) grade 4B and 6 cases (60%) grade 4C. Cholestasis was found in 1 patient in the NO-ACLF group (5%) and in 4 patients in the ACLF group (40%) (P = .03). We studied 30-day and 10-year survival respectively, which were 80% and 60% in the ACLF group and 83% and 70% in the NO-ACLF group (P = .794 and P = .657).

CONCLUSION

In this preliminary approach, clinical and histologic findings contributed to the differential diagnosis of ACLF. The mean MELD score at time of liver transplantations, total bilirubin levels, and histologically evident cholestasis were significantly higher in patients with ACLF than in those without ACLF.

Small bowel transplantation

BACKGROUND

Small bowel transplantation evolution, because of its complexity, was slower than other solid organs. Several advances have enabled its clinical application.

AIM

To review intestinal transplantation evolution and its current status.

METHOD

Search in MEDLINE and ScIELO literature. The terms used as descriptors were: intestinal failure, intestinal transplantation, small bowel transplantation, multivisceral transplantation. Were analyzed data on historical evolution, centers experience, indications, types of grafts, selection and organ procurement, postoperative management, complications and results.

CONCLUSION

Despite a slower evolution, intestinal transplantation is currently the standard therapy for patients with intestinal failure and life-threatening parenteral nutrition complications. It involves some modalities: small bowel transplantation, liver-intestinal transplantation, multivisceral transplantation and modified multivisceral transplantation. Currently, survival rate is similar to other solid organs. Most of the patients become free of parenteral nutrition.

[Histopathological changes in the small intestine after hypothermic preservation with University of Wisconsin and Euro-Collins solutions. Experimental study]

PURPOSE

The objective of this study is to compare small bowel histopathologic alterations under hypothermic preservation with University of Wisconsin (UW) and Euro-Collins (EC) solutions.

METHODS

In 40 Wistar rats (250-300g) the small bowel was microsurgically withdrawn and randomly treated with UW solution or EC solution. Periodic intestinal biopsies were taken from the proximal jejunum and distal ileum each 8 hours after small bowel withdrawing (time 0) until 48 hours. The histopathologic alterations were semiquantitatively classified in 4 degrees of severity and the obtained results were analysed statistically by appropriated tests (p < 0.05).

RESULTS

There was a significant increase of the small bowel ischaemic lesions over the time for both experimental groups. The lesions frequency and severity were significantly more increased in the EC group than in the UW group, for jejunal segments at 8 hours, in jejunal and ileal segments at 24 and in jejunal and ileal segments at 48 hours.

CONCLUSION

The UW solution did not avoid the development of small bowel ischaemic lesions but, with time, it protected better jejunal and ileal segments, decreasing frequency and severity of histopathological alterations, when compared to EC solution.