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Fruits are perishable fresh products with a short shelf life after harvesting. Perishable foods and their shelf lives are directly related to the temperature at which they are stored. Refrigeration is therefore essential in the conservation of fruits, as it allows the temperature to be lowered, helping to delay microbial, physiological, and chemical changes. This work aimed to compare the thermal behaviors of alveoli with different phase change materials (PCMs) placed inside a modular packaging developed for the transport and storage of fruits. The cooling tests were carried out inside a cold storage chamber with the set-point programmed to 2 °C. To simulate the placement in packages exposed to the store environment, heating tests were carried out while the chamber door was opened and the packaging was exposed to external environmental conditions. The phase change materials tested were RT2HC, RT5HC, and RT8HC. The temperature variation in the tests during cooling and heating proved that the new type of alveoli with PCM inside the fruit transport packaging is extremely important, as it can extend the useful life of the fruits after they are removed from the cold chamber, managing to maintain adequate conservation conditions for longer in contact with room temperature. The phase change material RT8HC was the one that showed the best results overall, managing to maintain the temperature of the fruit inside the packaging at a temperature below 10 °C for up to eight hours after being exposed to ambient conditions of 20 °C. [ABSTRACT FROM AUTHOR]

Abstract Background Despite their ability to regenerate as well as autografts, the use of nerve allografts is limited by the need for immunosuppression and the risk of disease transmission. Further, decellularized allografts lacking Schwann cells limit axonal regeneration in long nerve defects. This study evaluated sciatic nerve regeneration in rats implanted with cold- or cryopreserved allografts, and examined the effects of FK506, an immunosuppressant that targets calcineurin function, on motor recovery. Methods Sixty-five male Lewis rats were divided into five groups of 13, each with a 10-mm sciatic nerve gap. Group I received an autograft, whereas Groups II and III received allografts pretreated with cryopreservation and cold preservation, respectively. Groups IV and V were also implanted with cryo- and cold-preserved allografts, but were treated with a low dose of FK506. Motor regeneration was assessed at 20 weeks by the measurement of ankle contracture, compound muscle action potential, maximal isometric tetanic force, wet muscle weight of the tibialis anterior, peroneal nerve histomorphometry, and immunohistochemistry of the reconstructed sciatic nerve. Results Similar motor recovery was observed between the autografts and both types of allografts. The groups treated with FK506 showed improved recovery, particularly in terms of ankle angle and tibialis anterior muscle weight. Histomorphometry revealed a superior myelinated fiber area and nerve ratio in the cold-preserved allograft group, while Group II displayed a less well-organized morphology. Conclusion This study demonstrates that cold- or cryopreserved nerve allografts represent effective alternatives to autografts for peripheral nerve reconstruction, with low-dose FK506 enhancing motor recovery without necessitating immunosuppression. Level of Evidence I Basic Science Level I.

Background: Despite their ability to regenerate as well as autografts, the use of nerve allografts is limited by the need for immunosuppression and the risk of disease transmission. Further, decellularized allografts lacking Schwann cells limit axonal regeneration in long nerve defects. This study evaluated sciatic nerve regeneration in rats implanted with cold- or cryopreserved allografts, and examined the effects of FK506, an immunosuppressant that targets calcineurin function, on motor recovery. Methods: Sixty-five male Lewis rats were divided into five groups of 13, each with a 10-mm sciatic nerve gap. Group I received an autograft, whereas Groups II and III received allografts pretreated with cryopreservation and cold preservation, respectively. Groups IV and V were also implanted with cryo- and cold-preserved allografts, but were treated with a low dose of FK506. Motor regeneration was assessed at 20 weeks by the measurement of ankle contracture, compound muscle action potential, maximal isometric tetanic force, wet muscle weight of the tibialis anterior, peroneal nerve histomorphometry, and immunohistochemistry of the reconstructed sciatic nerve. Results: Similar motor recovery was observed between the autografts and both types of allografts. The groups treated with FK506 showed improved recovery, particularly in terms of ankle angle and tibialis anterior muscle weight. Histomorphometry revealed a superior myelinated fiber area and nerve ratio in the cold-preserved allograft group, while Group II displayed a less well-organized morphology. Conclusion: This study demonstrates that cold- or cryopreserved nerve allografts represent effective alternatives to autografts for peripheral nerve reconstruction, with low-dose FK506 enhancing motor recovery without necessitating immunosuppression. Level of Evidence I: Basic Science Level I. [ABSTRACT FROM AUTHOR]

The study investigated the effect of cold preservation on the nutritional composition of two fish species and the role of additives in restoring their quality. Fish samples were stored at 4±1°C for varying durations (0, 24, 48, 72, and 96 hours) and were analyzed. Results showed that proximate composition values progressively decreased with longer storage, while carbohydrate content significantly (P<0.05) increased. Fresh samples had the highest values for all parameters except carbohydrates, which showed the lowest values after 96 hours. Amino acid concentrations (essential and non-essential) did not significantly differ between fresh and stored fish. Leucine was the most abundant amino acid in the Wallago attu, with tryptophan being the least. In Heteropneustes fossilis, leucine and glutamic acid were the highest, while tryptophan and glutamine were the lowest. Mineral content generally declined with storage, except for calcium and zinc in Wallago attu and zinc and iron in Heteropneustes fossilis. Additives helped maintain nutritional value and extended fish shelflife during cold storage. However, significant nutrient loss occurred after an extended storage, which could be mitigated with additives. Cold storage remains a viable method for preserving fish taste and nutrition for a limited time. [ABSTRACT FROM AUTHOR]

Fruits are perishable fresh products with a short shelf life after harvesting. Perishable foods and their shelf lives are directly related to the temperature at which they are stored. Refrigeration is therefore essential in the conservation of fruits, as it allows the temperature to be lowered, helping to delay microbial, physiological, and chemical changes. This work aimed to compare the thermal behaviors of alveoli with different phase change materials (PCMs) placed inside a modular packaging developed for the transport and storage of fruits. The cooling tests were carried out inside a cold storage chamber with the set-point programmed to 2 °C. To simulate the placement in packages exposed to the store environment, heating tests were carried out while the chamber door was opened and the packaging was exposed to external environmental conditions. The phase change materials tested were RT2HC, RT5HC, and RT8HC. The temperature variation in the tests during cooling and heating proved that the new type of alveoli with PCM inside the fruit transport packaging is extremely important, as it can extend the useful life of the fruits after they are removed from the cold chamber, managing to maintain adequate conservation conditions for longer in contact with room temperature. The phase change material RT8HC was the one that showed the best results overall, managing to maintain the temperature of the fruit inside the packaging at a temperature below 10 °C for up to eight hours after being exposed to ambient conditions of 20 °C.

Introduction: We previously developed 3% trehalose-added lactated Ringer's solution (LR-3T) and 3% trehalose- and 5% dextran-40–added lactated Ringer's solution (LR-3T-5D), which can be used to preserve adipose-derived mesenchymal stem cells (hADSCs) for 24 h at 5 and 25 °C. However, it is necessary to further extend the storage duration of cells to expand transportation zones and ensure time for quality control testing of final cell products. Therefore, we attempted to prolong the preservation duration of hADSCs by adding supplements to LR-3T-5D. We focused on ascorbic acid as an antioxidant because it is widely clinically as a nutrient. Methods: We added the antioxidant ascorbic acid to LR-3T-5D and evaluated the viability, colony formation rate, proliferative capacity, and surface markers of hADSCs before and after preservation at 5 °C. Results: Analysis of the concentration of ascorbic acid added to LR-3T-5D indicated that 1000 mg/L was the optimal concentration for maintaining the viability of hADSCs after 72 h of cold preservation. No changes were observed in the expression of specific cell surface markers or in the potential of hADSCs to differentiate into adipocytes, osteoblasts, or chondrocytes before and after cold preservation. Discussion: These results suggest that cold preservation of hADSCs in LR-3T-5D supplemented with ascorbic acid helps maintain the quality of cells for use in cell therapy.

Cold preservation is a key component to organ procurement and transplantation. Cold preservation functions by slowing metabolic activity of procured organs and begins the period known as cold ischemic time (CIT). Reducing CIT and warm ischemic time (WIT) are paramount to minimizing donor organ damage from ischemia and the build-up of waste products and signals that drive reperfusion injury prior to transplantation into a matching recipient. Preventing damage from CIT and WIT and extending the amount of time that organs can tolerate has been a major goal of organ transplantation since donors and recipients are frequently not located within the same hospital, region, or state. Meanwhile, the amount of CIT that a transplant center is willing to accept differs based on the organ, the institution receiving the organ offer, and the doctor receiving the offer for that institution. With the introduction of a partial heart transplantation conducted last year at Duke University, it is important to discuss how much CIT transplant centers conducting a partial heart transplantation (pHT) are willing to accept. This article will review the physiology of WIT and CIT, associated organ damage, CIT variation among transplant centers and organ types, and provide a brief discussion of the future of pHT-accepted CIT and the need for research in this field.

Abstract Background Due to lower antioxidant capacity and higher amounts of polyunsaturated fatty acids, ram spermatozoa are very susceptible during cooling process. Objectives The objective was to examine the effect of the trans‐ferulic acid (t‐FA) on the ram semen during liquid preservation. Methods Semen samples were collected from the Qezel rams, pooled, and extended with the Tris‐based diluent. Pooled samples enriched with different amounts of the t‐FA (0, 2.5, 5, 10, and 25 mM) and preserved at 4°C for 72 h. Spermatozoa's kinematics, membrane functionality, and viability were assessed by CASA system, hypoosmotic swelling test, and eosin‐nigrosin staining, respectively. Moreover, biochemical parameters were measured at 0, 24, 48, and 72 h. Results Results showed that 5 and 10 mM t‐FA improved forward progressive motility (FPM) and curvilinear velocity compared to the other groups at 72 h (p < 0.05). Samples treated with 25 mM t‐FA showed the lowest total motility, FPM, and viability at 24, 48, and 72 h of storage (p < 0.05). Higher total antioxidant activity levels were observed in the 10 mM t‐FA‐treated group compared to the negative control at 72 h (p < 0.05). Treatment with 25 mM t‐FA increased malondialdehyde amounts and decreased superoxide dismutase activity compared to other groups at the final time assessment (p < 0.05). Nitrate‐nitrite and lipid hydroperoxides values were not affected by treatment. Conclusions The current study indicates the positive and negative influences of different concentrations of t‐FA on the ram semen upon cold storage.

Cold preservation is a key component to organ procurement and transplantation. Cold preservation functions by slowing metabolic activity of procured organs and begins the period known as cold ischemic time (CIT). Reducing CIT and warm ischemic time (WIT) are paramount to minimizing donor organ damage from ischemia and the build-up of waste products and signals that drive reperfusion injury prior to transplantation into a matching recipient. Preventing damage from CIT and WIT and extending the amount of time that organs can tolerate has been a major goal of organ transplantation since donors and recipients are frequently not located within the same hospital, region, or state. Meanwhile, the amount of CIT that a transplant center is willing to accept differs based on the organ, the institution receiving the organ offer, and the doctor receiving the offer for that institution. With the introduction of a partial heart transplantation conducted last year at Duke University, it is important to discuss how much CIT transplant centers conducting a partial heart transplantation (pHT) are willing to accept. This article will review the physiology of WIT and CIT, associated organ damage, CIT variation among transplant centers and organ types, and provide a brief discussion of the future of pHT-accepted CIT and the need for research in this field. [ABSTRACT FROM AUTHOR]

BACKGROUND: Pitanga (Eugenia uniflora L.) is a South American berry with a sweet flavor and is rich in bioactive compounds and antioxidants. However, its high water and sugar content, susceptibility to spoilage, and bruising limit its shelf life. OBJECTIVE: This study aimed to investigate the physical and chemical changes of pitanga during storage and to identify the optimal harvest time and storage conditions. METHODS: Pitangas were harvested at mid or full-ripeness stages, stored at 2°C, 10°C, or 20°C, and analyzed for physical and chemical quality attributes using a kinetic approach. RESULTS: The storage temperature of pitanga significantly affected the kinetics of various quality attributes, including weight loss, percentage of damaged and decayed fruit, fruit hardness, total soluble solid content, and color change. However, the ripening stage during harvest only influenced the initial values of a few quality attributes. The bioactive compound content and antioxidant capacity of pitanga were not significantly affected by either storage temperature or ripening stage, except for vitamin C. CONCLUSIONS: Pitanga can be preserved at 2°C for 20 days, resulting in a four-fold increase in shelf life compared to current postharvest practices. This finding offers valuable insights into optimizing the postharvest technology of pitanga, thereby increasing its utilization and promoting sustainable production practices. [ABSTRACT FROM AUTHOR]

Background: Due to lower antioxidant capacity and higher amounts of polyunsaturated fatty acids, ram spermatozoa are very susceptible during cooling process. Objectives: The objective was to examine the effect of the trans‐ferulic acid (t‐FA) on the ram semen during liquid preservation. Methods: Semen samples were collected from the Qezel rams, pooled, and extended with the Tris‐based diluent. Pooled samples enriched with different amounts of the t‐FA (0, 2.5, 5, 10, and 25 mM) and preserved at 4°C for 72 h. Spermatozoa's kinematics, membrane functionality, and viability were assessed by CASA system, hypoosmotic swelling test, and eosin‐nigrosin staining, respectively. Moreover, biochemical parameters were measured at 0, 24, 48, and 72 h. Results: Results showed that 5 and 10 mM t‐FA improved forward progressive motility (FPM) and curvilinear velocity compared to the other groups at 72 h (p < 0.05). Samples treated with 25 mM t‐FA showed the lowest total motility, FPM, and viability at 24, 48, and 72 h of storage (p < 0.05). Higher total antioxidant activity levels were observed in the 10 mM t‐FA‐treated group compared to the negative control at 72 h (p < 0.05). Treatment with 25 mM t‐FA increased malondialdehyde amounts and decreased superoxide dismutase activity compared to other groups at the final time assessment (p < 0.05). Nitrate‐nitrite and lipid hydroperoxides values were not affected by treatment. Conclusions: The current study indicates the positive and negative influences of different concentrations of t‐FA on the ram semen upon cold storage. [ABSTRACT FROM AUTHOR]

Objective: To assess the possible effect of hyperbaric oxygen (HBO) in preventing hypoxic-ischemic damage in cold-preserved organs. Methods: Visceral organs of white male New Zealand rabbits (n=6) were removed and examined in two groups: right kidneys (n=6), right lungs (n=6), right lobe of livers (n=6) and the hearts of three animals constituted the HBO group and left kidneys (n=6), left lungs (n=6), left lobe of livers (n=6) and the hearts of the remaining animals (n=3) formed the control group. After excision, organs in the HBO group were immediately placed in 100% oxygen at 2.5 atmosphere absolute for 2 h while those in the control group were kept in room air during this period. All tissues were kept in University of Wisconsin (UW) solution, 4 °C, at the end of the experiment. Tissue sections were obtained at 2 h after removal (T1, early stage) and at 125% of the maximal acceptable ischemic time determined for each tissue (T2, late stage). Histopathological evaluation was made by blinded pathologists using semiquantitative scoring systems and scores were compared between the HBO and control groups. Results: Tissue injury in the lungs and kidneys of the HBO group was milder compared to controls at both the early and late stages, but the difference was not statistically significant. Heart tissue in both the HBO and control groups demonstrated signs of ischemic injury at T2, while liver tissue did not change significantly from T1 to T2. Conclusion: These preliminary results suggest that further studies with larger sample sizes, particularly involving lung and kidney tissue and conditions applicable to clinical settings, are needed to determine any effect of HBO during cold storage.

Static cold storage (SCS) is the standard technique for organ preservation during transplantation, resulting in cold ischemic injury. Hypoxia can induce pannexin 1 (Panx1) channels to open, leading to release of adenosine triphosphate. However, it is unknown if Panx1 plays a role in SCS. In this study, livers from Panx1 -/- mice exhibited reduced adenosine triphosphate release, resulting in hepatocyte protection during preservation. The donor liver damage was decreased during SCS when Panx1 activity was blocked. Transmission electron microscopy revealed a decrease in mitochondria-associated endoplasmic reticulum membranes and improved mitochondria morphology. Mechanistically, Panx1 blockade upregulated the phosphatidylinositol 3-kinase-protein kinase B pathway and increased B cell leukemia/lymphoma 2 levels to combat apoptosis during liver preservation. The data indicate that blocking Panx1 during preservation of the donor liver can effectively improve mitochondrial function and reduce cellular stress damage thereby decreasing cold ischemia and reperfusion-related injuries in liver transplantation., Competing Interests: Declaration of competing interest The authors of this manuscript have no conflicts of interest to disclose as described by the American Journal of Transplantation., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Chlorella vulgaris cells were maintained over six months (or tentatively) using three protocols: two-week subculturing (positive control), storage at 4∘C, and simple abandonment (negative control). Cultures were monitored by their optical and cell densities over the trial period. Cells were characterized by their size, pigment profile, photosystem II status (OJIP test), electron transport rate assay (light curve), and lag phase duration when regrown. The abandoned cultures quickly showed cells deviating from their nominal state (increased size, a loss of their pigments, a negative alteration of their photosynthetic capacity, and an extended lag phase when inoculated into fresh medium). Frequent subculturing yielded reasonably stable performances. Yet, our experience showed that uncontrollable factors (human errors, lack of communication between teams) could expose the cultures to unfortunate incidents. 4∘C preservation allowed the cells to have a constant size and a slightly increased, yet stable, pigment profile associated to a dark acclimation (+12 % total chlorophyll). Finally, regrowth tests demonstrated that 4∘C preservation induces slightly improved performance (lag phase duration reduced by 9.5 %) than frequent subculturing. Those findings advocate for the use of 4∘C preservation to reduce cell maintenance work and conserve a pool of cells in a similar state to be used as repeatable inoculum for larger-scale experiments while nullifying otherwise batch-to-batch variation effects. Subculturing work can be reduced from once every two weeks to once every six months at least. [Display omitted] • Chlorella vulgaris was preserved over six months. • Frequent subculturing and 4∘C preservation were similar overall. • Frequent subculturing exposes cells to human error. • 4∘C preservation provides stable and repeatable inoculum. • Cell maintenance could also be reduced accordingly. [ABSTRACT FROM AUTHOR]

BackgroundKidneys from brain-dead donors are cold preserved until transplanted. However, prolonged cold storage can contribute to allograft failure. Studies suggest that donor preconditioning with dopaminergics may reduce cold-ischemic transplant injury, but whether heme oxygenase (HO)-1 induction is an underlying mechanism is not known.ObjectiveTo test whether preconditioning with fenoldopam (FD) induce HO-1 and protect kidneys against cold storage injury and whether HO-1 plays a role in protection.MethodWe used human renal proximal tubular epithelial cells, rat kidney transplants, and HO-1 null mice kidneys.ResultsFD preconditioning of cells for 4 hr significantly protected against cell death from 24-hr cold hypoxia and was associated with a dose-dependent increase in HO-1 expression. In a syngeneic rat kidney transplant model, FD preconditioning for 18 hr markedly increased kidney HO-1 expression and protected kidneys against 24-hr cold-ischemic transplant injury. To test the role of HO-1, renal proximal tubular epithelial cells were treated with HO-1 small interfering RNA, followed by FD-preconditioning. Small interfering RNA inhibited the HO-1 messenger RNA expression and reversed the FD protection. Suspension of kidneys of HO-1 null and wild-type mice preconditioned with FD or saline were subjected to 24- and 48-hr cold storage. N-acetyl glucosaminidase, a specific tubular injury marker, was significantly lower in FD-preconditioned wild-type kidneys, but not in HO-1 null kidneys, suggesting a role for HO-1 in FD's preconditioning.ConclusionOur data suggest HO-1 induction as an underlying mechanism for FD preconditioning and support the idea of testing FD preconditioning in the clinical setting. Studies are required to determine the optimum FD-preconditioning protocol.

Abstract This study aimed to assess the cryoprotectant effect of vacuum packaging (35 and 45 kPa) on cold preserved (0 °C and -18 °C) fillets of Yamú (Brycon amazonicus), during 5 days of storage. We analyzed the physicochemical and microbiological changes in the fillets during storage time. Yamú’s water holding capacity, nitrogenated bases content (TVB-N) and texture (N) were affected (p ≤ 0.05) by time and temperature. Bacterial colonies in fillets did not represent a risk for human health after five days of storage. In conclusion, vacuum packing positively (p ≤ 0.05) reduces the effect of cold over Yamú fillets properties.

Summary: The growing use of marginal organs for transplantation pushes current preservation methods toward their limits, and the need for improvement is pressing. We previously demonstrated the benefits of M101, a natural extracellular oxygen carrier compatible with hypothermia, for the preservation of healthy renal grafts in a porcine model of autotransplantation. Herein, we use a variant of this preclinical model to evaluate M101 potential benefits both in static cold storage (CS) and in machine perfusion (MP) preservation in the transplantation outcomes for marginal kidneys. In the CS arm, despite the absence of obvious benefits within the first 2 weeks of follow‐up, M101 dose‐dependently improved long‐term function, normalizing creatininemia after 1 and 3 months. In the MP arm, M101 improved short‐ and long‐term functional outcomes as well as tissue integrity. Importantly, we provide evidence for the additivity of MP and M101 functional effects, showing that the addition of the compound further improves organ preservation, by reducing short‐term function loss, with no loss of function or tissue integrity recorded throughout the follow‐up. Extending previous observations with healthy kidneys, the present results point at the M101 oxygen carrier as a viable strategy to improve current organ preservation methods in marginal organ transplantation. [ABSTRACT FROM AUTHOR]

Cold ischemic injury to the intestine during preservation remains an unresolved issue in transplantation medicine. Autophagy, a cytoplasmic protein degradation pathway, is essential for metabolic adaptation to starvation, hypoxia, and ischemia. It has been implicated in the cold ischemia (CI) of other transplantable organs. This study determines the changes in intestinal autophagy evoked by cold storage and explores the effects of autophagy on ischemic grafts. Cold preservation was simulated by placing the small intestines of Wistar rats in an IGL-1 (Institute George Lopez) solution at 4 °C for varying periods (3, 6, 9, and 12 h). The extent of graft preservation injury (mucosal and cellular injury) and changes in autophagy were measured after each CI time. Subsequently, we determined the differences in apoptosis and preservation injury after activating autophagy with rapamycin or inhibiting it with 3-methyladenine. The results revealed that ischemic injury and autophagy were induced by cold storage. Autophagy peaked at 3 h and subsequently declined. After 12 h of storage, autophagic expression was reduced significantly. Additionally, enhanced intestinal autophagy by rapamycin was associated with less tissue, cellular, and apoptotic damage during and after the 12-h long preservation. After reperfusion, grafts with enhanced autophagy still presented with less injury. Inhibiting autophagy exhibited the opposite trend. These findings demonstrate intestinal autophagy changes in cold preservation. Furthermore, enhanced autophagy was protective against cold ischemia–reperfusion damage of the small bowels.

Context Renal transplantation is the best treatment modality for replacement of lost renal function in patients with end-stage renal disease. Nevertheless, the gap between the number of kidneys available for donation and the number of patients waiting for an organ is increasing due to an increase in the number of patients with renal failure and, simultaneously, a shortage of kidneys for transplant. Objective To review the policies available for kidney donation. Evidence acquisition A review of literature was performed to describe the available policies. Rates of donation were compared according to the different policies for several Western countries. Evidence synthesis The classical donor type is the deceased heart-beating donor after brain death; however, shortage of organs forced the expansion of the criteria for donation. The concepts of expanded criteria donation and donation after circulatory death have been adopted more recently. Scores based on donor characteristics and histology criteria from kidney biopsies are also used to refine the quality of organs used for transplantation. Live donation is still marginal in many countries. Conclusions There is an urgent need to increase public awareness of kidney transplantation, to improve strategies to identify new potential donors, and to master the techniques of retrieving and preserving organs. Increasing live donation is also essential to overcome organ shortage. Patient summary There is an urgent need to increase public awareness of kidney transplantation, to improve strategies to identify new potential donors, and to master the techniques of retrieving and preserving organs. Increasing live donation is also essential to overcome organ shortage. [ABSTRACT FROM AUTHOR]

Because inhaled carbon monoxide (CO) provides potent anti-inflammatory and antioxidant effects against ischemia reperfusion injury, we hypothesized that treatment of organ donors with inhaled CO would decrease graft injury after heart transplantation. Hearts were heterotopically transplanted into syngeneic Lewis rats after 8 hours of cold preservation in University of Wisconsin solution. Donor rats were exposed to CO at a concentration of 250 parts per million for 24 hours via a gas-exposure chamber. Severity of myocardial injury was determined by total serum creatine phosphokinase and troponin I levels at three hours after reperfusion. In addition, Affymetrix gene array analysis of mRNA transcripts was performed on the heart graft tissue prior to implantation. Recipients of grafts from CO-exposed donors had lower levels of serum troponin I and creatine phosphokinase; less upregulation of mRNA for interleukin-6, intercellular adhesion molecule-1, and tumor necrosis factor-α; and fewer infiltrating cells. Although donor pretreatment with CO altered the expression of 49 genes expressly represented on the array, we could not obtain meaningful data to explain the mechanisms by which CO potentiated the protective effects.Pretreatment with CO gas before organ procurement effectively protected cardiac grafts from ischemia reperfusion-induced injury in a rat heterotopic cardiac transplant model. A clinical report review indicated that CO-poisoned organ donors may be comparable to non-poisoned donors. [ABSTRACT FROM AUTHOR]

OBJECTIVES: Brain death (BD) is associated with various systemic responses and a cascade of inflammatory reactions. It is still unknown how the time interval from BD to cold preservation (CP) affects outcome after lung transplantation (LTx). This report investigates the impact of the time interval from BD to CP on long-term outcome in LTx. METHODS: We reviewed 250 consecutive recipients who underwent LTx at our institution between January 2000 and December 2011. In Group I (n = 212), the time interval from BD to CP was <24 h, and in Group II (n = 38) >24 h. Cox proportional hazard regression analysis was performed to determine the risk factors affecting survival. RESULTS: The median time from BD to CP was 18.6 h (range 9-65). The rate of postoperative complications was comparable (P = 0.8). The 30-day mortality rate was 7.5% in Group I and 0% in Group II. The 5-year survival rate was better in Group II [70% (95% CI: 48.5-83.8%)] than in Group I [66% (95% CI: 58.3-72.5%)] without statistical significance (P = 0.3). Intraoperative extracorporeal membrane oxygenation (ECMO) use was identified as a significant risk factor for survival [HR = 1.7, (95% CI: 1.1-2.6), P = 0.01]. CONCLUSION: In our cohort, the time interval from BD to CP had no impact on long-term outcome after LTx. [ABSTRACT FROM AUTHOR]

Longterm pancreatic cold ischemia contributes to decreased islet number and viability after isolation and culture, leading to poor islet transplantation outcome in patients with type 1 diabetes. In this study, we examined mechanisms of pancreatic cold preservation and rewarming-induced injury by interrogating the proapoptotic gene BBC3/ Bbc3, also known as Puma (p53 upregulated modulator of apoptosis), using three experimental models: 1) bioluminescence imaging of isolated luciferase-transgenic (“Firefly”) Lewis rat islets, 2) cold preservation of en bloc-harvested pancreata from Bbc3-knockout (KO) mice, and 3) cold preservation and rewarming of human pancreata and isolated islets. Cold preservation-mediated islet injury occurred during rewarming in “Firefly” islets. Silencing Bbc3 by transfecting Bbc3 siRNA into islets in vitro prior to cold preservation improved postpreservation mitochondrial viability. Cold preservation resulted in decreased postisolation islet yield in both wild-type and Bbc3 KO pancreata. However, after culture, the islet viability was significantly higher in Bbc3-KO islets, suggesting that different mechanisms are involved in islet damage/loss during isolation and culture. Furthermore, Bbc3-KO islets from cold-preserved pancreata showed reduced HMGB1 (high-mobility group box 1 protein) expression and decreased levels of 4-hydroxynonenal (4-HNE) protein adducts, which was indicative of reduced oxidative stress. During human islet isolation, BBC3 protein was upregulated in digested tissue from cold-preserved pancreata. Hypoxia in cold preservation increased BBC3 mRNA and protein in isolated human islets after rewarming in culture and reduced islet viability. These results demonstrated the involvement of BBC3/Bbc3 in cold preservation/rewarming-mediated islet injury, possibly through modulating HMGB1- and oxidative stress-mediated injury to islets [ABSTRACT FROM AUTHOR]

OBJECTIVES: Adenosine monophosphate-activated protein kinase (AMPK) is a master regulator of energy metabolism and has been shown to be protective in ischaemia/reperfusion injury (IRI). We hypothesized that preactivation of AMPK with an activator before donor heart procurement could protect heart grafts from cold IRI. METHODS: Donor Sprague-Dawley rats were injected intravenously with AMPK activator 5-amino-imidazole-4-carboxamide ribonucleotide (AICAR) or vehicle 30 min before heart procurement. Heart grafts were then preserved in histidine-tryptophan-ketoglutarate (HTK) solution at 4°C for 8 h. After preservation, grafts were immediately mounted on the Langendorff perfusion system and perfused with Krebs-Henseleit buffer at 37°C for 1 h. Adenosine triphosphate (ATP) and malondialdehyde (MDA) content in graft tissue were quantified post-preservation and post-reperfusion. After reperfusion, isolated heart function was assessed using a pressure transducer; cumulative release of creatine kinase (CK) and lactate dehydrogenase (LDH) into the perfusate was measured to assess cardiomyocyte necrosis; ultrastructural changes in the mitochondria of the grafts were examined using transmission electron microscopy (TEM). RESULTS: After preservation, myocardial ATP content in the pretreated hearts was significantly higher than in the control hearts (3.247 ± 0.3034 vs 1.817 ± 0.2533 μmol/g protein; P < 0.05). AICAR-pretreated heart grafts exhibited significantly higher coronary flow (9.667 ± 0.3159 vs 8.033 ± 0.2459 ml/min; P < 0.05) and left ventricular developing pressure (58.67 ± 2.894 vs 42.67 ± 3.333 mmHg; P < 0.05) than the vehicle treated after reperfusion. Cumulative release of CK (300.0 ± 25.30 vs 431.7 ± 42.39 U/l; P < 0.05) and LDH (228.0 ± 16.68 vs 366.8 ± 57.41 U/l; P < 0.05) in the perfusate was significantly lower in the AICAR-pretreated group than that in the control group. Myocardial MDA content was also reduced in the pretreated group (0.5167 ± 0.1046 vs 0.9333 ± 0.1333 nmol/mg protein; P < 0.05). TEM suggested that the mitochondrial structure of AICAR-pretreated hearts was much better preserved. Moreover, AICAR-pretreated hearts significantly diminished cytosolic cytochrome c release after reperfusion. CONCLUSIONS: This study demonstrates that pretreatment with AMPK activator AICAR significantly protects heart grafts from extended cold IRI. This novel protocol may be useful and feasible in clinical heart transplantation. [ABSTRACT FROM AUTHOR]

Livers cold preserved during variable periods of ischemia suffer functional, morphological and hemodynamic alteration, which are exacerbated when they are reperfused. One important injury is glycogen depletion during cold ischemia/ reperfusion. How liver can restore their energy during reperfusion is related with the preservation time, nutritional status of the donor, and the preservation solution used. However, there are some treatments that help livers to preserve their energy storage. These procedures used drugs or metabolites, which are added to the liver to maintain their glycogen storage during preservation, time and allow the organ to restore its energy during reperfusion. There are several publications where the nutritional status of the donor was studied. There is controversy about the quality or the donor organ. Some authors say that fasted animals are better donors because this condition reduced hepatic injuries; others think that fed animals provide the necessary glycogen (energy) to improve liver preservation, reducing morphological and functional damages. Many others are convinced that nutritional status of the donor is not relevant because hepatic injuries will occurred even though the donor was fed or not. The preservation solution has an important role in reducing liver damages during cold ischemia/reperfusion and in restoring liver energy storage. Storage in HLR (histidine, lactobionate and raffinose) solution facilitated the resuscitation of energetic status and preserved adenine nucleotide levels significantly greater than Marshall’s citrate or Bretschneider’s histidine-based solution (HTK). University of Wisconsin (UW) proved to be suitable for energy recovery during reperfusion. In conclusion, the aim of this review is to present studies performed by different authors where they analyzed preservation/reperfusion injuries, how the liver restores its energy storage during reperfusion time, different strategies to avoid glycogen depletion during cold ischemia/reperfusion, the efficacy of preservation solutions and the effect of nutritional status of the donor to prevent functional alteration of the liver during cold preservation.

Cold liver preservation in the University of Wisconsin solution (UW) followed by reperfusion alters hepatic parenchyma and extra cellular matrix. In this study we analyzed the benefit of adding either 500 μM Sodium Nitroprusside (NPNa) or 100 μM S-nitrosoglutathione (GSNO) as Nitric Oxide (NO) donors to the UW solution to prevent hepatic injury. Wistar adult rat livers were stored in UW solution (0°C) for 48Hs and reperfused (60 minutes) in the isolated perfused rat liver model (IPRL). Untreated livers were used as normal controls. Livers perfused but not preserved were used as controls of reperfusion. Parenchyma damages were evaluated by Hematoxylin-Eosin stain. Picrosirius Red and Gordon-Sweets stains were used for collagen and reticulin networks, respectively. An inmunohistochemistry assay for albumin was used as functional test. Cold preservation step was followed by swollen hepatocytes with “light empty halos” surrounding the nucleus, conserved hepatocyte cords and many rounded endothelial cells. The addition of NPNa or GSNO into UW solution, avoid these alterations. Livers preserved for 48 Hs and then reperfused showed extended areas of vacuolation around central veins, and many endothelial cells were rounded and located inside sinusoidal lumens. The collagen network was disorganized while the reticulin one was less altered. Albumin was distributed preferentially in pericentral areas. On the contrary, livers preserved in presence of NPNa or GSNO did not show vacuolation and both collagen and reticulin networks were unchanged. Albumin was more homogeneously distributed in both groups. In conclusion, the addition of 500 μ NPNa or 100 μ GSNO as a NO donor, improves UW solution properties to preserve rat livers by maintaining the hepatic morphology and avoiding hepatic injury post-cold preservation/reperfusion.

Livers cold preserved in University of Wisconsin (UW) solution followed by reperfusion suffer ischemia/reperfusion injuries. Microcirculation is the primary target of damage, characterized by sinusoidal perfusion failure due, mainly, to morphological changes of sinusoidal endothelial cells. Here, we demonstrated that the addition of S-nitrosoglutathione (GSNO) to the UW solution before cold storage, as a nitric oxide (NO) donor, attenuated hepatic injuries.Wistar adult rat livers were stored in UW solution (0°C – 48 hs) and then reperfused during 60 minutes using the Isolated Perfused Rat Model (IPRL). We assayed four GSNO concentration (50, 100, 250 and 500 μM). NO concentration was estimated calculating the amount of nitrite (NO2 -) generated in the UW solution. Injuries during cold preservation were established measuring lactate dehydrogenase (LDH) released to the UW solution. Meanwhile, intrahepatic resistance (IR), LDH released to the perfusate, the effluent/perfusate ratio for K+, bile flow, liver glycogen content and sinusoidal endothelial cell morphology were studied after 1 hour of reperfusion in the IPRL system.In cold preserved livers without GSNO, glycogen content was dramatically reduced, IR increased markedly, LDH released was high, bile flow diminished and sinusoidal endothelial cells appeared rounded and detached from perisinusoidal matrix after reperfusion. The presence of 100 μM GSNO prevented the IR rise and LDH release, improved bile production and partially reduced endothelial cells damages.In conclusion, the addition of 100 μM GSNO to UW solution improved hemodynamic and function capacity of cold preserved/reperfused livers.

Background: Cell therapy, such as hepatocyte transplantation (HTx), is promising for the treatment of metabolic liver diseases or as a bridge to orthotopic liver transplantation in patients with fulminant liver failure. However, one of the limitations of this therapy is the shortage of donors. The present study aims to investigate whether the two-layer method (TLM) of cold preservation with oxygenation improves the viability and activity of hepatocytes from rat donation after cardiac death (DCD) donors compared with results obtained with the University of Wisconsin (UW) solution. Moreover, we evaluated the hepatocyte function after culture or transplantation into the spleen. Materials and Methods: We used male Sprague-Dawley rats for this study. The DCD model was induced by phrenotomy after injecting heparin. We assigned rats based on warm ischemia times of 15 and 30 min to groups S and L, respectively. Each group (n = 5) was then subdivided as follows: (1) group S: not preserved (S/N), preserved by TLM for 3 h (S/TLM3) and 12 h (S/TLM12), and in the UW solution for 3 h (S/UW3) and 12 h (S/UW12), and (2) group L: not preserved (L/N), preserved by TLM for 3 h (L/TLM3) and 12 h (L/TLM12), and in the UW solution for 3 h (L/UW3) and 12 h (L/UW12). The cell viability and function of isolated DCD hepatocytes were analyzed for culture or HTx into the spleen. Results: The viability and ATP levels of DCD hepatocytes significantly improved after TLM compared with the values after preservation in cold UW solution in group S/N (p < 0.059). The levels of albumin production and urea synthesis by hepatocytes after culture were significantly higher in groups S/TLM3 and S/TLM12 than in groups S/UW3 and S/UW12 (p < 0.05), respectively. Further, serum albumin levels after HTx were also markedly higher in groups S/TLM3 and S/TLM12 than in groups S/UW3 and S/UW12. The morphological features revealed that cultured and transplanted hepatocytes remained clearly viable and maintained an expression for specific hepatic function, such as the production of albumin and glycogen. Conclusion: This novel method of oxygenated cold preservation of DCD livers can expand the hepatocyte donor pool for HTx and establish a wider application of this developing technique. © 2015 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Cardioprotective effects of necrostatin-1 (necroptosis inhibitor) and 3-methyladenine (autophagy inhibitor) were studied on the model of long-term cold preservation of rat heart. Addition of necrostatin-1 (490 nmol/liter) or 3-methyladenine (4.5 mmol/liter) to custodiol preserving solution reduced myocardial infarction size and improved left-ventricular function during reperfusion after 8-h preservation at 4°C. Inhibition of necroptosis and autophagy contributed to the cardioprotective effect under conditions of cold preservation of the donor heart. [ABSTRACT FROM AUTHOR]

Protection of intestinal graft mucosa during cold preservation is still an unmet need in clinical practice, thus affecting the success of transplantation. The present study investigates the ability of two ischemic preconditioning (IPC) procedures to limit cold preservation injury. Three groups of Sprague–Dawley rats were recruited (n = 11 each) as follows: the short IPC (SIPC) performed through 4 cycles of mesenteric ischemia of 4 min each followed by 10 min of reperfusion, the long IPC (LIPC) obtained by 2 ischemic cycles of 12 min each followed by 10 min of reperfusion, and the control group (C) without IPC. Grafts were then stored in cold histidine–tryptophan–ketoglutarate solution and samples were taken at 0, 3, 6 and 9 h lasting preservation. Both IPC groups showed an advanced degree of preservation with delayed development of graft mucosa damage, mainly in the crypt region. At the beginning of preservation, the graft mucosa in both IPC groups showed lower degree of mucosal injury index (MII) by 50% in comparison with C group. Specifically, a significant improvement of MII was observed after 3 h of preservation in the LIPC group ( p < 0.05) in comparison with untreated C grafts. Significant atrophy of the intestinal mucosa in C group was found after 3 h of preservation ( p < 0.01), in SIPC group the progress of atrophy was delayed to 6 h ( p < 0.001), and in LIPC group only moderate decrease in that was found. A parallel increase of laminin expression with the MII rate after 6 and 9 h of preservation in comparison with the level at time 0 was observed in all grafts ( p < 0.001 and p < 0.01, respectively). In both IPC groups the apoptotic cell (AC) rate was significantly reduced at the beginning of cold preservation ( p < 0.05 both). Moreover, in both the SIPC and C groups, the progressive increase in MII rate connected with AC rate decrease was due to a predominance of necrosis. By contrast in the LIPC group, after an increase of nearly 50% in the AC rate at the 3rd hour, its level remained fairly constant during the further 6 h of preservation, thus probably preventing necrosis and improving graft viability. [ABSTRACT FROM AUTHOR]