University Of Wisconsin Preservation Solution Research Articles

Post-reperfusion syndrome among liver transplant recipients in HTK (Histidine- Tryptophan- Ketoglutarate) versus UW (University of Wisconsin) preservation solution

Post-reperfusion syndrome among liver transplant recipients in HTK (Histidine- Tryptophan- Ketoglutarate) versus UW (University of Wisconsin) preservation solution

Ex Vivo Thrombolysis to Salvage Free Flaps Using Machine Perfusion: A Pilot Study in a Porcine Model

Mechanical evacuation of capillary thrombi in free flaps is difficult, and often requires thrombolytic therapy. Utilizing machine perfusion systems, the possibility rises to salvage free flaps ex vivo by administering high doses of thrombolytic agents. The primary aim of this pilot study in a porcine model is to investigate the feasibility of ex vivo thrombolysis using an extracorporeal perfusion machine. A model of stasis-induced thrombosis was used in 12 free rectus abdominis flaps harvested from six Dutch Landrace pigs. Compromised flaps were ex vivo perfused with University of Wisconsin preservation solution and treated according to the following study groups: (1) 1 mg of tissue plasminogen activator (t-PA) as additive, (2) 3 mg of t-PA as an additive, and (3) no thrombolytic additive. Microcirculation was assessed using near-infrared fluorescence angiography. Pedicled abdominal flaps were created and thrombus formation was successfully induced. Eleven abdominal flaps were perfused using the modified heart-lung machine setup. Near-infrared fluorescence angiography showed delayed or no filling was noted in the control group. In comparison, the flaps which were perfused with 1 mg t-PA or 3 mg t-PA as additive showed increased fluorescence intensity curves. This pilot study in a porcine model presents a reliable and reproductive stasis-induced thrombosis model in free flaps. By adding t-PA to a custom-made extracorporeal perfusion system, the indocyanine green fluorescence intensity curves increased of all flaps that were perfused with different dosages of t-PA as additives, indicating restoration of capillary pressure and microcirculatory inflow.

Reproducible porcine model for kidney allotransplantation of low weight miniature pig.

BackgroundMultiple porcine models have been established to study the mechanisms regarding kidney transplantation. With the development of xenotransplantation, the demand for a low weight miniature pig model has been increasing. A reliable and reproducible surgical technique to establish these models, and to address possible obstacles, has not been sufficiently defined in detail. The goal of the present study was to develop and optimize a low weight miniature pig porcine kidney transplantation model, including a comprehensive surgical description.MethodsEight male Bama miniature pigs (12–15 kg) were randomly chosen as kidney donors and, to facilitate investigation of the transplanted kidney, had undergone contralateral nephrectomy. The procured kidneys were perfused with iced saline then immediately cold stored in the University of Wisconsin preservation solution. The recipients were randomly allocated to left-to-right or right-to-right groups. Serum creatinine and urine volume were recorded post-transplantation, and the pigs underwent euthanasia at seven days post-transplantation.ResultsAll eight pigs showed functioning grafts, immediately producing urine post-transplantation. The serum creatinine level increased the following transplantation gradually and reached a peak on the day of euthanasia. One renal artery thrombosis and one ureterovesical entrance stenosis were observed in the right-to-right group. No complications were observed in the left-to-right group.ConclusionsWe developed and optimized a reproducible porcine kidney transplantation model in the low weight miniature pig. Moreover, we addressed and emphasized critical points of the left-to-right transplantation surgery and detailed the anatomic techniques to avoid stenosis of blood vessels and prevent ureterovesical stricture.

Type of Preservation Solution, UW or HTK, Has an Impact on the Incidence of Biliary Stricture following Liver Transplantation: A Retrospective Study.

Organ preservation plays a crucial role in the outcome following solid organ transplantation. The aim of this study was to perform a retrospective outcome analysis following liver transplantation using histidine tryptophan ketoglutarate (HTK) or the University of Wisconsin (UW) solutions for liver graft preservation. We retrospectively reviewed data on adult patients who were liver-transplanted at Karolinska University Hospital between 2007 and 2015. There was evaluation of donor and recipient characteristics, pre- and post-transplant blood chemistry tests, biliary and vascular complications, graft dysfunction and nonfunction, and patient and graft survivals. A total of 433 patients were included in the analyses, with 230 and 203 patients having received livers preserved with HTK and UW, respectively. Mean follow-up was 45 ± 29 months for the HTK group and 42.4 ± 26 for the UW group. There was no difference between the two groups either in terms of patient and graft survival, or of results of postoperative blood chemistry, or incidence of arterial complications, early allograft dysfunction, or primary graft nonfunction. However, the incidence of biliary stricture was higher in the UW group (22.7%) versus the HTK group (13.5%; p=0.013). Use of UW and HTK preservation solution in liver transplantation has no impact on patient and graft survival. However, use of HTK solution results in a lower incidence of posttransplant biliary stricture.

Organ preservation with targeted rapamycin nanoparticles: a pre-treatment strategy preventing chronic rejection in vivo.

Hypothermic preservation is the standard of care for storing organs prior to transplantation. Endothelial and epithelial injury associated with hypothermic storage causes downstream graft injury and, as such, the choice of an ideal donor organ preservation solution remains controversial. Cold storage solutions, by design, minimize cellular necrosis and optimize cellular osmotic potential, but do little to assuage immunological cell activation or immune cell priming post transplantation. Thus, here we explore the efficacy of our previously described novel Targeted Rapamycin Micelles (TRaM) as an additive to standard-of-care University of Wisconsin preservation solution as a means to alter the immunological microenvironment post transplantation using in vivo models of tracheal and aortic allograft transplantation. In all models of transplantation, grafts pre-treated with 100 ng mL−1 of TRaM augmented preservation solution ex vivo showed a significant inhibition of chronic rejection post-transplantation, as compared to UW augmented with free rapamycin at a ten-fold higher dose. Here, for the first time, we present a novel method of organ pretreatment using a nanotherapeutic-based cellular targeted delivery system that enables donor administration of rapamycin, at a ten-fold decreased dose during cold storage. Clinically, these pretreatment strategies may positively impact post-transplant outcomes and can be readily translated to clinical scenarios.

MP29-17 HYDROGEN SULFIDE TREATMENT MITIGATES DONOR TISSUE NECROSIS DURING PROLONGED COLD STORAGE AND IMPROVES SURVIVAL FOLLOWING ALLOGENEIC RENAL TRANSPLANTATION.

You have accessJournal of UrologyTransplantation & Vascular Surgery: Renal Transplantation & Vascular Surgery I1 Apr 2016MP29-17 HYDROGEN SULFIDE TREATMENT MITIGATES DONOR TISSUE NECROSIS DURING PROLONGED COLD STORAGE AND IMPROVES SURVIVAL FOLLOWING ALLOGENEIC RENAL TRANSPLANTATION. Ian Lobb, Weihua Liu, Jifu Jiang, Dameng Lian, and Alp Sener Ian LobbIan Lobb More articles by this author , Weihua LiuWeihua Liu More articles by this author , Jifu JiangJifu Jiang More articles by this author , Dameng LianDameng Lian More articles by this author , and Alp SenerAlp Sener More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2016.02.1101AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Organ procurement is inherently associated with ischemia-reperfusion injury (IRI), resulting from loss and subsequent restoration of blood flow, which is detrimental to short- and long-term graft function and survival. Treatment of donor organs with small molecules such as hydrogen sulfide (H2S) is a novel method of modulating prolonged IRI during transplantation. We postulated that H2S treatment during prolonged cold storage could mitigate IRI-induced renal allograft injury following allogeneic renal transplantation (RTx). METHODS Following bilateral native nephrectomy, recipient Lewis rats underwent RTx with kidneys obtained from Brown Norway donor rats that were flushed with either University of Wisconsin preservation solution (UW group; n=8) or UW + 150 µM NaHS (H2S group; n=5) and stored for 24 hours at 4°C in the same solution. Sham surgeries (midline incision only; n=5) were also performed and animals were monitored for 14 days to assess allograft function and survival. An additional subset of donor kidneys in each treatment group (n=8 per group) were perfused with 5 μM Ethidium Homodimer-1 (EthD-1) immediately following cold storage and analyzed via fluorescent microscopy for in situ characterization of tissue necrosis. ATP levels were also measured to assess the metabolic state of donor kidneys following cold storage. RESULTS H2S treated animals exhibited significantly improved (p<0.05) survival and markedly decreased serum creatinine compared to UW treatment alone. Donor kidneys supplemented with H2S exhibited significantly decreased (p<0.05) EthD-1 staining and markedly improved ATP levels compared to UW treated kidneys immediately following cold storage. CONCLUSIONS H2S treatment mitigates IRI associated with prolonged cold storage and acutely improves subsequent allograft function and survival. H2S appears to limit tissue necrosis and may maintain cellular metabolism during prolonged cold storage. H2S treatment could represent a novel and cost-effective method of protecting kidneys during transplantation and improving clinical transplant outcomes. © 2016FiguresReferencesRelatedDetails Volume 195Issue 4SApril 2016Page: e386-e387 Advertisement Copyright & Permissions© 2016MetricsAuthor Information Ian Lobb More articles by this author Weihua Liu More articles by this author Jifu Jiang More articles by this author Dameng Lian More articles by this author Alp Sener More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

720 Analysis of de novo urologic cancer in kidney transplant recipients: Single center study of 3,951 cases

from loss and subsequent restoration of blood flow, which is detrimental to shortand long-term graft function and survival. Treatment of donor organs with small molecules such as hydrogen sulfide (H2S) is a novel method of modulating prolonged IRI during transplantation. We postulated that H2S treatment during prolonged cold storage could mitigate IRI-induced renal allograft injury following allogeneic renal transplantation (RTx). METHODS: Following bilateral native nephrectomy, recipient Lewis rats underwent RTx with kidneys obtained from Brown Norway donor rats that were flushed with either University of Wisconsin preservation solution (UWgroup; n1⁄48) or UW+150 mMNaHS (H2Sgroup; n1⁄45) and stored for 24 hours at 4 C in the same solution. Sham surgeries (midline incision only; n1⁄45) were also performed and animals were monitored for 14 days to assess allograft function and survival. An additional subset of donor kidneys in each treatment group (n1⁄48 per group) were perfused with 5 mM Ethidium Homodimer-1 (EthD-1) immediately following cold storage and analyzed via fluorescent microscopy for in situ characterization of tissue necrosis. ATP levels were also measured to assess the metabolic state of donor kidneys following cold storage. RESULTS: H2S treated animals exhibited significantly improved (p<0.05) survival and markedly decreased serum creatinine compared to UW treatment alone. Donor kidneys supplemented with H2S exhibited significantly decreased (p<0.05) EthD-1 staining and markedly improved ATP levels compared to UW treated kidneys immediately following cold storage. CONCLUSIONS: H2S treatment mitigates IRI associated with prolonged cold storage and acutely improves subsequent allograft function and survival. H2S appears to limit tissue necrosis and may maintain cellular metabolism during prolonged cold storage. H2S treatment could represent a novel and cost-effective method of protecting kidneys during transplantation and improving clinical transplant outcomes.

Hydrogen Sulfide Treatment Mitigates Renal Allograft Ischemia-Reperfusion Injury during Cold Storage and Improves Early Transplant Kidney Function and Survival Following Allogeneic Renal Transplantation

Ischemia-reperfusion injury is unavoidable during organ transplantation. Prolonged ischemia-reperfusion injury is detrimental to short-term and long-term graft function and survival. H2S is a recently characterized, endogenously produced gaseous molecule with important physiological roles that has been shown to be cytoprotective during tissue ischemia-reperfusion injury. The current study aimed to determine whether H2S could mitigate cold renal ischemia-reperfusion injury in the clinically relevant context of allogeneic renal transplantation. Following bilateral native nephrectomy Lewis rats underwent renal transplantation with kidneys from Brown Norway donor rats that were flushed with cold (4C) standard University of Wisconsin preservation solution (University of Wisconsin preservation solution group) or cold University of Wisconsin preservation solution plus 150 μM NaHS (H2S group) solution. Kidneys were stored for 6 hours at 4C in the same solution. Recipient animals were monitored for 14 days or until sacrifice using metabolic cages to assess various parameters of renal graft function. H2S treatment improved early allograft survival and function, and decreased early levels of necrosis, apoptosis and Kim-1 compared to University of Wisconsin preservation solution alone. H2S treatment did not affect allograft rejection. Rather, it modulated the early allograft transcriptome to decrease the expression of renal injury, coagulation and cellular stress response genes, and increase the expression of cellular proliferation and Ifn-γ induced genes compared to University of Wisconsin preservation solution alone. To our knowledge our findings are the first to show that H2S protects donor kidneys against cold ischemia-reperfusion injury in the context of allogeneic renal transplantation. This potentially represents a novel cost-effective therapeutic solution to mitigate ischemia-reperfusion injury and improve the clinical outcomes of renal transplantation.

Losartan activates sirtuin 1 in rat reduced-size orthotopic liver transplantation

To investigate a possible association between losartan and sirtuin 1 (SIRT1) in reduced-size orthotopic liver transplantation (ROLT) in rats. Livers of male Sprague-Dawley rats (200-250 g) were preserved in University of Wisconsin preservation solution for 1 h at 4 °C prior to ROLT. In an additional group, an antagonist of angiotensin II type 1 receptor (AT1R), losartan, was orally administered (5 mg/kg) 24 h and 1 h before the surgical procedure to both the donors and the recipients. Transaminase (as an indicator of liver injury), SIRT1 activity, and nicotinamide adenine dinucleotide (NAD(+), a co-factor necessary for SIRT1 activity) levels were determined by biochemical methods. Protein expression of SIRT1, acetylated FoxO1 (ac-FoxO1), NAMPT (the precursor of NAD+), heat shock proteins (HSP70, HO-1) expression, endoplasmic reticulum stress (GRP78, IRE1α, p-eIF2) and apoptosis (caspase 12 and caspase 3) parameters were determined by Western blot. Possible alterations in protein expression of mitogen activated protein kinases (MAPK), such as p-p38 and p-ERK, were also evaluated. Furthermore, the SIRT3 protein expression and mRNA levels were examined. The present study demonstrated that losartan administration led to diminished liver injury when compared to ROLT group, as evidenced by the significant decreases in alanine aminotransferase (358.3 ± 133.44 vs 206 ± 33.61, P < 0.05) and aspartate aminotransferase levels (893.57 ± 397.69 vs 500.85 ± 118.07, P < 0.05). The lessened hepatic injury in case of losartan was associated with enhanced SIRT1 protein expression and activity (5.27 ± 0.32 vs 6.08 ± 0.30, P < 0.05). This was concomitant with increased levels of NAD(+) (0.87 ± 0.22 vs 1.195 ± 0.144, P < 0.05) the co-factor necessary for SIRT1 activity, as well as with decreases in ac-FoxO1 expression. Losartan treatment also provoked significant attenuation of endoplasmic reticulum stress parameters (GRP78, IRE1α, p-eIF2) which was consistent with reduced levels of both caspase 12 and caspase 3. Furthermore, losartan administration stimulated HSP70 protein expression and attenuated HO-1 expression. However, no changes were observed in protein or mRNA expression of SIRT3. Finally, the protein expression pattern of p-ERK and p-p38 were not altered upon losartan administration. The present study reports that losartan induces SIRT1 expression and activity, and that it reduces hepatic injury in a ROLT model.

Histomorphometric evaluation of ischemia-reperfusion injury and the effect of preservation solutions histidine-tryptophan-ketoglutarate and University of Wisconsin in limb transplantation.

The effect of cold ischemia (CI) in vascularized composite allotransplantation is unknown. We herein assess tissue-specific damage, acceptable CI time, and the effect of preservation solutions in a syngenic rat hindlimb transplant model. Lewis rat limbs were flushed and stored for 2, 10, or 30 hr CI in saline, histidine-tryptophan-ketoglutarate or University of Wisconsin preservation solution before transplantation. Morphologic alterations, inflammation, and damage of the individual tissues were analyzed on day 10 using histomorphology, confocal, light, and transmission-electron microscopy. Two-hour CI led to mild inflammation of tissues on day 10, whereas 10-hr and 30-hr CI resulted in massive inflammation and tissue damage. Although muscle was mainly affected after prolonged CI (≥10 hr), nerve was affected in all CI groups. A perineural cell infiltrate, hypercellular appearance, pronounced vacuolization, and mucoid degeneration, appearing as Wallerian degeneration, were observed. Staining with propidium iodide and Syto 16 revealed a decrease in viable muscle cell nuclei in the anterior tibial muscle on day 10 in all groups, which was most pronounced in 10-hr and 30-hr CI animals. Transmission-electron microscopy indicated that a large number of mitochondria were degenerated in the 10-hr and 30-hr CI groups. Histidine-tryptophan-ketoglutarate preservation solution slightly decreased inflammation and tissue damage compared to University of Wisconsin-treated and saline-treated animals, especially in skin and muscle when CI times did not exceed 10 hr. Severe inflammation and tissue damage are observed after prolonged CI in muscle and nerve. Ischemia times in vascularized composite allotransplantation should be kept as short as possible and certainly below 10 hr.

P31 Hydrogen sulfide treatment improves graft function and survival following prolonged cold ischemia and allogeneic renal transplantation

Organ procurement is inherently associated with ischemia–reperfusion injury (IRI), resulting from loss and subsequent restoration of blood flow, and is detrimental to graft function and survival. Treatment of donor organs with small molecules such as hydrogen sulfide (H 2 S) may be a novel method of mitigating IRI during transplantation. We postulated that H 2 S treatment could mitigate IRI during cold organ storage and subsequent genetically mismatched (allogeneic) renal transplantation (RTx), improving allograft function and survival. Following bilateral native nephrectomy, recipient Lewis rats underwent RTx with kidneys obtained from Brown Norway donor rats that were flushed with either University of Wisconsin preservation solution (UW group) or UW + H 2 S (150 μM NaHS; H 2 S group) and stored for 24 h at 4°C in the same solution. Serum was obtained on subsequent post-operative (PO) days and creatinine was used as a surrogate marker of graft function. H 2 S treated animals exhibited significantly improved survival compared to UW animals ( p < 0.01), with UW animals exhibiting 0% survival by PO day 4 and H 2 S treated animals retaining 20% survival by PO day 14 (end of time course). As well, UW treated animals exhibited markedly increased serum creatinine levels at both PO days 2 and 4 compared to H 2 S animals. These findings indicate that H 2 S treatment can mitigate graft injury following prolonged periods of cold IRI, improving initial graft function and possibly delaying graft rejection. H 2 S treatment could represent a novel method of mitigating IRI during transplantation, thereby improving clinical outcomes.

Polyethylene glycol rinse solution: an effective way to prevent ischemia-reperfusion injury.

To test whether a new rinse solution containing polyethylene glycol 35 (PEG-35) could prevent ischemia-reperfusion injury (IRI) in liver grafts. Sprague-Dawley rat livers were stored in University of Wisconsin preservation solution and then washed with different rinse solutions (Ringer's lactate solution and a new rinse solution enriched with PEG-35 at either 1 or 5 g/L) before ex vivo perfusion with Krebs-Heinseleit buffer solution. We assessed the following: liver injury (transaminase levels), mitochondrial damage (glutamate dehydrogenase activity), liver function (bile output and vascular resistance), oxidative stress (malondialdehyde), nitric oxide, liver autophagy (Beclin-1 and LCB3) and cytoskeleton integrity (filament and globular actin fraction); as well as levels of metalloproteinases (MMP2 and MMP9), adenosine monophosphate-activated protein kinase (AMPK), heat shock protein 70 (HSP70) and heme oxygenase 1 (HO-1). When we used the PEG-35 rinse solution, reduced hepatic injury and improved liver function were noted after reperfusion. The PEG-35 rinse solution prevented oxidative stress, mitochondrial damage, and liver autophagy. Further, it increased the expression of cytoprotective heat shock proteins such as HO-1 and HSP70, activated AMPK, and contributed to the restoration of cytoskeleton integrity after IRI. Using the rinse solution containing PEG-35 was effective for decreasing liver graft vulnerability to IRI.

Comparison of New Preservation Solutions, HN-1 and University of Wisconsin Solution, in Pancreas Preservation for Porcine Islet Isolation.

For pancreatic islet transplantation, maintaining organ viability after pancreas procurement is critical and a major determinant for better graft function and survival. University of Wisconsin (UW) solution is currently the gold standard for abdominal organ preservation and the pancreas in particular. However, in the use of UW preservation solution for islet transplantation, there are disadvantages to be overcome, such as the inhibition of collagenase activity during pancreatic digestion. In this study, we compared UW solution with HN-1 solution in pancreas preservation for islet isolation. Islet yield was significantly greater in the HN-1 group than the UW group both before and after purification. In the in vitro assay, the adenosine triphosphate content in cultured islets was significantly higher in the HN-1 group than in the UW group. Furthermore, in streptozotocin-induced diabetic nude mice, the islet graft function of the HN-1 group was superior to that of the UW group. We concluded that the use of HN-1 solution is a promising approach for optimal pancreas preservation in islet transplantation.

Proteasome inhibitors protect the steatotic and non-steatotic liver graft against cold ischemia reperfusion injury

BackgroundThe dramatic shortage of organs leads to consider the steatotic livers for transplantation although their poor tolerance against ischemia reperfusion injury (IRI). Ubiquitin proteasome system (UPS) inhibition during hypothermia prolongs myocardial graft preservation. The role of UPS in the liver IRI is not fully understood. Bortezomib (BRZ) treatment at non-toxic doses of rats fed alcohol chronically has shown protective effects by increasing liver antioxidant enzymes. We evaluated and compared both proteasome inhibitors BRZ and MG132 in addition to University of Wisconsin preservation solution (UW) at low and non-toxic dose for fatty liver graft protection against cold IRI. ExperimentalSteatotic and non-steatotic livers have been stored in UW enriched with BRZ (100nM) or MG132 (25μM), for 24h at 4°C and then subjected to 2-h normothermic reperfusion (37°C). Liver injury (AST/ALT), hepatic function (bile output; vascular resistance), mitochondrial damage (GLDH), oxidative stress (MDA), nitric oxide (NO) (e-NOS activity; nitrates/nitrites), proteasome chymotrypsin-like activity (ChT), and UPS (19S and 20S5 beta) protein levels have been measured. ResultsChT was inhibited when BRZ and MG132 were added to UW. Both inhibitors prevented liver injury (AST/ALT), when compared to UW alone. BRZ increased bile production more efficiently than MG132. Only BRZ decreased vascular resistance in fatty livers, which correlated with an increase in NO generation (through e-NOS activation) and AMPK phosphorylation. GLDH and MDA were also prevented by BRZ. In addition, BRZ inhibited adiponectin, IL-1, and TNF alpha, only in steatotic livers. ConclusionMG132 and BRZ, administrated at low and non toxic doses, are very efficient to protect fatty liver grafts against cold IRI. The benefits of BRZ are more effective than those of MG132. This evidenced for the first time the potential use of UPS inhibitors for the preservation of marginal liver grafts and for future applications in the prevention of IRI.

Tauroursodeoxycholic Acid Affects PPARγ and TLR4 in Steatotic Liver Transplantation

Numerous steatotic livers are discarded for transplantation because of their poor tolerance to ischemia-reperfusion (I/R). We examined whether tauroursodeoxycholic acid (TUDCA), a known inhibitor of endoplasmic reticulum (ER) stress, protects steatotic and nonsteatotic liver grafts preserved during 6 h in University of Wisconsin (UW) solution and transplanted. The protective mechanisms of TUDCA were also examined. Neither unfolded protein response (UPR) induction nor ER stress was evidenced in steatotic and nonsteatotic liver grafts after 6 h in UW preservation solution. TUDCA only protected steatotic livers grafts and did so through a mechanism independent of ER stress. It reduced proliferator-activated receptor-γ (PPARγ) and damage. When PPARγ was activated, TUDCA did not reduce damage. TUDCA, which inhibited PPARγ, and the PPARγ antagonist treatment up-regulated toll-like receptor 4 (TLR4), specifically the TIR domain-containing adaptor inducing IFNβ (TRIF) pathway. TLR4 agonist treatment reduced damage in steatotic liver grafts. When TLR4 action was inhibited, PPARγ antagonists did not protect steatotic liver grafts. In conclusion, TUDCA reduced PPARγ and this in turn up-regulated the TLR4 pathway, thus protecting steatotic liver grafts. TLR4 activating-based strategies could reduce the inherent risk of steatotic liver failure after transplantation.

Supplemental hydrogen sulphide protects transplant kidney function and prolongs recipient survival after prolonged cold ischaemia–reperfusion injury by mitigating renal graft apoptosis and inflammation

What's known on the subject? and What does the study add? Hydrogen sulphide (H(2) S) has recently been classified as a member of the family of small gaseous molecules called gasotransmitters and has been found to have many important physiological functions. Several recent studies have elucidated the protective effects of H(2) S in many models of tissue ischaemia-reperfusion injury (IRI), including hepatic, myocardial, pulmonary, cerebral and renal IRI. It has previously been shown that H(2) S has a number of properties that may contribute to its protection against IRI, including vasodilatory, anti-apoptotic, anti-inflammatory and anti-oxidant effects, although the specific actions appear to vary between tissues. The few studies investigating the effects of H(2) S against renal IRI have only involved clamping of the renal pedicle to induce warm IRI. This study investigated the protective effects of H(2) S in the context of renal transplantation (RTx), which generally involves a more severe period of prolonged cold IRI. A previous study investigated the actions of H(2) S in RTx, but it was performed ex vivo and did not involve actual transplantation of donor kidneys. To our knowledge, this is the first study using a clinically relevant model of RTx to show that treatment of donor kidneys with H(2) S during preservation is protective against prolonged cold IRI. These findings suggest that H(2) S has potential utility in improving clinical organ preservation techniques and increasing the overall success of organ transplantation. • To characterize the effects of hydrogen sulphide (H(2) S), an endogenously produced molecule recently described to have protective effects against warm ischaemic tissue injury, in mitigating transplantation-associated prolonged cold ischaemia-reperfusion injury (IRI) in a clinically applicable in vivo model of renal transplantation (RTx). • After undergoing bilateral native nephrectomy, Lewis rats underwent RTx with kidneys that were flushed with either cold (4 °C) standard University of Wisconsin preservation solution (UW) or cold UW + 150 µM NaHS (H(2) S) solution and stored for 24 h at 4 °C in the same solution. • Recipient rats were monitored for a 14-day time course using metabolic cages to assess various characteristics of renal graft function. • Renal grafts were removed at time of death or after the rats were killed for histological, immunohistochemical and quantitative PCR analysis. • H(2) S-treated rats exhibited immediate and significant (P < 0.05) decreases in serum creatinine levels, increased urine output and increased survival compared with UW-treated rats. • H(2) S-treated grafts showed significantly reduced glomerular and tubular necrosis and apoptosis, diminished graft neutrophil and macrophage infiltrates and a trend towards improved inflammatory and anti-apoptotic cytokine profiles. • Our results provide the first evidence that supplemental H(2) S can mitigate renal graft IRI incurred during transplantation and prolonged cold storage, improving early graft function and recipient survival in a clinically applicable model of RTx.

Assessment of Epiphyseal Plate Allograft Viability and Function After Ex Vivo Storage in University of Wisconsin Solution

Compromised epiphyseal plate function can result in limb deformities. Microvascular transplantation of an epiphyseal plate allograft is a potentially effective approach to reestablish longitudinal limb growth. For this procedure to become clinically useful, the technique for temporary ex vivo storage of allografts must be reliable. The goal of this study was to determine a time frame for which proximal tibial epiphyseal plate allografts could be stored in University of Wisconsin Preservation Solution (UWPS) and remain functional in vivo after microvascular transplantation. Proximal tibial epiphyseal plate allografts from skeletally immature female New Zealand White rabbits (10 to 12 wk of age) were used. Allografts (isolated on the popliteal arteriovenous pedicle) were stored ex vivo in cold UWPS for periods of up to 21 days. Chondrocyte viability, phenotype, and extracellular matrix composition of growth plate cartilage was assessed. Microvascular transplantations of nonstored or prestored (3 d) allografts were performed and analysis of bromodeoxyuridine and calcein incorporation was done to determine chondrocyte proliferation and new bone growth, respectively. In vitro analysis showed that, compared with control tissue, epiphyseal plate chondrocyte viability (P>0.05), organization, and collagen extracellular matrix was preserved up to 4 days in cold UWPS. Microvascular transplantation of nonstored epiphyseal plate allografts was successful. Despite care being taken to ensure vascular patency during the microvascular procedure, transplantation of prestored allografts failed due to absent flow in the larger vessels and in the allograft based upon the visualization of organized thrombus within the vascular pedicle, and absent flow within the composite graft itself. However, growth plate viability and function was detected in a peripheral region of a single allograft where partial blood flow had been maintained during the transplantation period. Ex vivo storage in cold UWPS for 3 days maintains growth plate chondrocyte viability and function in vivo. However, future studies must be directed toward investigating the direct effect of ex vivo storage on the integrity and function of the vascular pedicles.

Bone Morphogenetic Protein-7 Reduces Cold Ischemic Injury in Rat Kidney

Background Deceased donor kidneys have a high incidence of delayed graft function attributable to ischemia–reperfusion injury. Although preservation solution and cold storage reduce cold ischemic injury, the depletion of cellular energy and oxidative signalling leads to cellular damage. Because bone morphogenetic protein-7 has renoprotective effect, we have hypothesized that recombinant human bone morphogenetic protein-7 (rh BMP-7) will better preserve kidney tissue exposed to prolonged cold ischemia in comparison with University of Wisconsin (UW) solution. We evaluated how the duration of cold ischemia influences the cold ischemic injury. Methods Levels of lipid peroxidation, protein carbonyl content, as well as superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities were determined in the kidneys by spectrophotometry after 6, 12, and 24 hours of cold ischemia. Results Time-dependent increases in the levels of lipid peroxidation and protein carbonyl content at all time points were significantly lower in rhBMP-7–perfused kidneys versus the UW-treated group. SOD activity after 6 hours, as well as GSH-Px activity after 24 hours of cold ischemia was significantly higher in the kidney tissue perfused by rhBMP-7 than in UW group. Conclusion rhBMP-7 significantly decreases cellular damage in rat kidney versus UW preservation solution and this is attributed to lowering of cold ischemia injury and maintaining prolonged tissue antioxidant activity.

Microvascular Transplantation of Epiphyseal Plate Allografts Following ex vivo Storage in University of Wisconsin Preservation Solution: Not a clinical study

Microvascular Transplantation of Epiphyseal Plate Allografts Following ex vivo Storage in University of Wisconsin Preservation Solution: Not a clinical study

Melatonin prolongs graft survival of pancreas allotransplants in pigs

Oxidative stress is involved in ischemia-reperfusion injury and allograft rejection after transplantation. We studied two well-known antioxidants, melatonin and ascorbic acid (AA), in relation to the survival of a pancreas transplantation model without immunosuppression. Forty-eight Landrace pigs were divided into three groups (n = 16 each; eight donors and eight recipients) that received melatonin, AA, or no antioxidant therapy (controls). Melatonin and AA were administered (10 mg/kg body weight) intravenously to donors and recipients during surgery and on postoperative days 1-7. The molecules were also added (5 mm) to a University of Wisconsin preservation solution during organ cold storage. Melatonin significantly delayed acute rejection and prolonged allograft survival (25.1 ± 7.7 days) compared with the controls (8.1 ± 0.8 days, P = 0.013) and the AA group (9.4 ± 1.6 days, P = 0.049). Melatonin reduced indicators of oxidative stress, malondialdehyde, and 4-hydroxyalkenals, in pancreatic samples collected during procurement, cold ischemia, and reperfusion. Melatonin also reduced serum pig-major acute-phase protein/inter-α-trypsin inhibitor heavy chain 4 (pMAP/ITIH(4)) in the early post-transplantation period. AA only partially reduced oxidative damage 30 min postreperfusion and failed to prevent pMAP/ITIH(4) elevations. These findings suggested that melatonin may be a useful therapeutic tool for organ transplantation.