Pubertal Girls With Overweight/Obesity Have Higher Androgen Levels-Can Metabolomics Tell us Why?

CONTEXT

Pubertal girls with higher total body fat (TBF) demonstrate higher androgen levels. The cause of this association is unknown but is hypothesized to relate to insulin resistance.

OBJECTIVE

This work aimed to investigate the association between higher TBF and higher androgens in pubertal girls using untargeted metabolomics.

METHODS

Serum androgens were determined using a quantitative mass spectrometry (MS)-based assay. Metabolomic samples were analyzed using liquid chromatography high-resolution MS. Associations between TBF or body mass index (BMI) z score (exposure) and metabolomic features (outcome) and between metabolomic features (exposure) and serum hormones (outcome) were examined using gaussian generalized estimating equation models with the outcome lagged by one study visit. Benjamini-Hochberg false discovery rate (FDR) adjusted P values were calculated to account for multiple testing. RaMP-DB (relational database of metabolomic pathways) was used to conduct enriched pathway analyses among features nominally associated with body composition or hormones.

RESULTS

Sixty-six pubertal, premenarchal girls (aged 10.9 ± 1.39 SD years; 60% White, 24% Black, 16% other; 63% normal weight, 37% overweight/obese) contributed an average of 2.29 blood samples. BMI and TBF were negatively associated with most features including raffinose (a plant trisaccharide) and several bile acids. For BMI, RaMP-DB identified many enriched pathways related to bile acids. Androstenedione also showed strong negative associations with raffinose and bile acids.

CONCLUSION

Metabolomic analyses of samples from pubertal girls did not identify an insulin resistance signature to explain the association between higher TBF and androgens. Instead, we identified potential novel signaling pathways that may involve raffinose or bile acid action at the adrenal gland.

Prolonged cold-preservation of domestic cat ovarian tissue is improved by extracellular solution but impaired by the fragmentation of ovary

For domestic cats ovaries, recommended cold-storage limit is 24 h in Phosphate Buffered Saline (PBS) or Dulbecco`s PBS (DPBS). Here, we attempted to verify wheatear cat ovaries may benefit from more complex solutions during prolonged cold-storage (>24 h). First, the preservation capabilities of extracellular (SP+), intracellular (UW) solutions and DPBS supplemented with glutathione (DPBS+GSH) were compared using ovary fragments from the same ovary (n=10). Intact ovary stored in DPBS served as a control. Ovaries were kept at 4 °C for 48 h, and 72 h. In the second experiment, first ovary was stored in DPBS, second in SP+ or UW solution for 48 h (n = 12). Ovaries pairs stored in DPBS for 24 h served as a control (n=8). Tissue samples were evaluated directly after cold-storage and after following 24 h in vitro culture. Ovarian follicle morphology, apoptosis rates (cleaved caspase-3, TUNEL), and follicular growth activation (Ki-67) were assessed. Ovary fragmentation impaired follicular morphology preservation upon cold-storage comparing to intact ovary. However, ovarian fragments stored in UW for 48 h and in SP+ for 72 h presented better morphology than DPBS+GSH group. Comparison of intact ovaries cold-storage for 48 h showed that SP+ provided superior follicular morphology over DPBS, and it was comparable to the outcome of 24-hour storage. No follicular activation after in vitro culture was observed. Nevertheless, tissue culture increased considerably caspase-3 cleavage and TUNEL detection. The ovary fragmentation prior to cold-storage is not recommended in domestic cats. Replacement of DPBS with SP+ solution for whole ovary and UW solution for ovarian tissue fragments improves follicular structure preservation during 48-hour cold-storage.

Effectiveness of metformin for the reversal of cold-ischemia-induced damage in hepatosteatosis

BACKGROUND

Primary dysfunction and rejection are more common in donor liver tissues with steatosis. AMP-activated protein kinase (AMPK) assumes organ-protective functions during ischemia. Metformin was used for the activation of AMPK in hepatocytes. The aim of this study is to investigate the effectiveness of metformin administration for the reversal of cold-ischemia-induced damage in hepatosteatosis.

MATERIAL AND METHODS

Seven-week-old C7BL56 male-mice (n = 109) were separated into four groups depending on diet type and metformin use. A specific diet model was followed for 10 weeks to induce hepatosteatosis. A group of the animals was administered with metformin for the last four weeks via oral gavage. After resection, the liver tissues were perfused and kept for 0-6-12-24 h in the UW solution. Histopathological examinations were performed, and Western blot was utilized to analyze p-AMPK and AMPK expression levels.

RESULTS

Hepatosteatosis decreased significantly with metformin. The steatotic liver group had more prominent pericentral inflammation, necrosis as well as showing a decreased and more delayed AMPK response than the non-fat group. All these alterations could be corrected using metformin.

CONCLUSION

Metformin can increase the resistance of livers with hepatosteatosis to cold-ischemia-induced damage, which in turn may pave the way for successful transplantation of fatty living-donor livers.

A Diversity Covering (DiCo) Plasmodium vivax apical membrane antigen-1 vaccine adjuvanted with RFASE/RSL10 yields high levels of growth-inhibitory antibodies

Plasmodium vivax malaria is increasingly recognized as a major global health problem and the socio-economic impact of P.vivax-induced burden is huge. Vaccine development against P. vivax malaria has been hampered by the lack of an in vitro culture system and poor access to P. vivax sporozoites. The recent generation of Plasmodium falciparum parasites that express a functional P. vivax AMA1 molecule has provided a platform for in vitro evaluation of PvAMA1 as a potential blood stage vaccine. Three so-called PvAMA1 Diversity Covering (DiCo) proteins were designed to assess their potential to induce a functional and broad humoral immune response to the polymorphic PvAMA1 molecule. Rabbits were immunized with the mixture of three, Pichia-produced, PvAMA1 DiCo proteins, as well as with 2 naturally occurring PvAMA1 alleles. For these three groups, the experimental adjuvant raffinose fatty acid sulfate ester (RFASE) was used, while in a fourth group the purified main mono-esterified constituent (RSL10) of this adjuvant was used. Animals immunized with the mixture of the three PvAMA1 DiCo proteins in RFASE showed high anti-PvAMA1 antibody titers against three naturally occurring PvAMA1variants while also high growth-inhibitory capacity was observed against P. falciparum parasites expressing PvAMA1. This supports further clinical development of the PvAMA1 DiCo mixture as a potential malaria vaccine. However, as the single allele PvAMA1 SalI-group showed similar characteristics in antibody titer and inhibition levels as the PvAMA1 DiCo mixture-group, this raises the question whether a mixture is really necessary to overcome the polymorphism in the vaccine candidate. RFASE induced strong humoral responses, as did the animals immunized with the purified component, RSL10. This suggests that RSL10 is the active ingredient. However, one of the RSL10-immunized animal showed a delayed response, necessitating further research into the clinical development of RSL10.

Effect of PERLA®, a new cold-storage solution, on oxidative stress injury and early graft function in rat kidney transplantation model

BACKGROUND

The composition of organ preservation solutions is crucial for maintaining graft integrity and early graft function after transplantation. The aim of this study is to compare new organ preservation solution PERLA® with the gold standard preservation solution University of Wisconsin (UW) regarding oxidative stress and early graft injury.

METHODS

In order to assess oxidative stress after cold storage, kidney grafts have been preserved for 18 h at 4° C in either UW solution or PERLA® solution and then assessed for oxidative stress injury (protocol 1). To assess kidney injuries and oxidative stress after reperfusion, rat kidneys were harvested, stored in cold UW or in PERLA® solutions for 18 h at 4 °C and then transplanted heterotopically for 6 h (protocol 2). PERLA® is a high Na+/low K+ solution including PEG-35 (1 g/L), trimetazidine (1 µM), carvedilol (10 µM) and tacrolimus (5 µM).

RESULTS

Our results showed that preservation of kidneys in PERLA® solution significantly attenuates oxidative stress parameters after cold storage and reperfusion. We found a significant decrease in oxidative damage indicators (MDA, CD and CP) and a significant increase in antioxidant indicators (GPx, GSH, CAT, SOD and PSH). Moreover, PERLA® solution decreased kidney injury after reperfusion (creatinine, LDH and uric acid).

CONCLUSION

PERLA® solution was more effective than UW storage solution in preserving rat's kidney grafts.

Significantly Improved Cold Preservation of Rat Hind Limb Vascularized Composite Allografts Using the New PrC-210 Free Radical Scavenger

Vascularized composite allotransplantation (VCA) represents a promising reconstructive solution primarily conducted to improve quality of life. However, tissue damage caused by cold-ischemia (CI) storage prior to transplant represents a major factor limiting widespread application. This study investigates the addition of the novel free radical scavenger PrC-210 to UW Organ Preservation Solution (UW Solution) to suppress CI-induced skeletal muscle injury in a rat hind limb amputation model. Lewis rats received systemic perfusion of UW solution +/- PrC-210 (0 mM control, 10 mM, 20 mM, 30 mM, or 40 mM), followed by bilateral transfemoral amputation. Limbs were stored in 40 mL of the same perfusate at 4 °C for 48 h. Muscle punch biopsies were taken at set times over the 48 h cold-storage period and analyzed for caspase-3,7 activity, cytochrome C levels, and qualitative histology. A single 15 s perfusion of PrC-210-containing UW Solution conferred a dose-dependent reduction in CI-induced muscle cell death over 48 h. In the presence of PrC-210, muscle cell mitochondrial cytochrome C release was equivalent to 0 h controls, with profound reductions in the caspase-3,7 apoptotic marker that correlated with limb histology. PrC-210 conferred complete prevention of ROS-induced mitochondrial lysis in vitro, as measured by cytochrome C release. We conclude that the addition of 30 mM PrC210 to UW Solution conferred the most consistent reduction in CI limb damage, and it warrants further investigation for clinical application in the VCA setting.

Milk fat globule membrane protects Bifidobacterium longum ssp. infantis ATCC 15697 against bile stress by modifying global transcriptional responses

The milk fat globule membrane (MFGM) can protect probiotic bacteria from bile stress. However, its potential mechanism has not been reported. In this study, the viability, morphology and gene transcriptional response of Bifidobacterium longum ssp. infantis ATCC 15697 (BI_15697) stressed by bile salts with or without MFGM were investigated. It was shown that MFGM alleviated the reduction in BI_15697 population induced by 0.2% porcine bile stress and restored the population to the control levels. MFGM ameliorated the shrunken, fragmented appearance and irregular morphology of BI_15697 and maintained cell integrity disrupted by bile stress. RNA-sequencing results showed that MFGM increased transport of glucose and raffinose and decreased that of branched-chain amino acids (BCAA) in the presence of bile salts. MFGM stimulated the expression of genes involved in the synthesis of raffinose in galactose metabolism and the metabolism of BCAA, suggesting that MFGM stimulated the accumulation of raffinose and BCAA in the presence of bile. In addition, MFGM stimulated the expression of 2 bile efflux transporters under bile stress. Together, the multifactorial response helps BI_15697 excrete bile salts and maintain cellular integrity in response to bile stress. This study proposes a mechanism for the protection of BI_15697 against bile salt stress by MFGM, thereby providing a molecular basis for its application in incorporation of probiotics.

Polymyxin B sulfate inhalable microparticles with high-lectin-affinity sugar carriers for efficient treatment of biofilm-associated pulmonary infections

Pulmonary infections caused by multidrug-resistant bacteria have become a significant threat to human health. Bacterial biofilms exacerbate the persistence and recurrence of pulmonary infections, hindering the accessibility and effectiveness of antibiotics. In this study, a dry powder inhalation (DPI) consisting of polymyxin B sulfate (PMBS) inhalable microparticles and high-lectin-affinity (HLA) sugar (i.e., raffinose) carriers was developed for treating pulmonary infections and targeting bacterial lectins essential for biofilm growth. The formulated PMBS-HLA DPIs exhibited particle sizes of approximately 3 μm, and surface roughness varied according to the drug-to-carrier ratio. Formulation F5 (PMBS: raffinose = 10:90) demonstrated the highest fine particle fraction (FPF) value (64.86%), signifying its substantially enhanced aerosol performance, potentially attributable to moderate roughness and smallest mass median aerodynamic particle size. The efficacy of PMBS-HLA DPIs in inhibiting biofilm formation and eradicating mature biofilms was significantly improved with the addition of raffinose, suggesting the effectiveness of lectin-binding strategy for combating bacterial biofilm-associated infections. In rat models with acute and chronic pulmonary infections, F5 demonstrated superior bacterial killing and amelioration of inflammatory responses compared to spray-dried PMBS (F0). In conclusion, our HLA carrier-based formulation presents considerable potential for the efficient treatment of multidrug-resistant bacterial biofilm-associated pulmonary infections.

Prebiotics and the Risk of Upper Digestive Tract and Stomach Cancers: The PrebiotiCa Study

BACKGROUND

Fiber intake may lower digestive tract cancer risk, possibly by modulating the composition of gut microbiota. However, no data are available about the role of specific fiber fractions with prebiotic activity (e.g., inulin-type fructans (ITFs), fructo-oligosaccharides (FOSs) and galactooligosaccharides (GOSs)) on the risk lower digestive tract cancers.

OBJECTIVE

The objective was to assess the association between prebiotic intake and the risk of cancers of the upper digestive tract and stomach.

DESIGN

Within the PrebiotiCa study, data were derived from a network of Italian case-control studies conducted between 1992 and 2009. Participants' usual diet was assessed using a food frequency questionnaire. ITFs, and selected FOSs (nystose, kestose, and 1F-β-fructofuranosylnystose) and GOSs (raffinose and stachyose) were quantified in several food products via laboratory analyses. Participants' prebiotic intake was calculated by multiplying food frequency questionnaire intake by the prebiotic content of each food item.

PARTICIPANTS/SETTING

Cases were patients admitted to major hospitals with incident histologically confirmed cancers; there were 946 cases of cancer of the oral cavity/pharynx, 198 of the nasopharynx, 304 of the esophagus, 230 of the stomach. More than 4,000 patients admitted to the same hospitals for acute nonneoplastic and not diet-related conditions were selected as control subjects.

MAIN OUTCOME MEASURES

The outcomes were oral and pharyngeal, nasopharyngeal, esophageal, and stomach cancers.

STATISTICAL ANALYSES PERFORMED

The odds ratios and corresponding 95% CIs of the various cancers were derived using logistic regression models adjusted for major confounders and energy intake.

RESULTS

No association was observed between intake of prebiotics and risk of cancers of the oral cavity and pharynx, nasopharynx, and esophagus. High raffinose intake reduced stomach cancer risk (odds ratio for the third vs the first tertile 0.6, 95% CI 0.3 to 0.9); no other prebiotic was associated with stomach cancer.

CONCLUSIONS

The current study does not support a major role of prebiotic fibers on selected upper digestive tract cancers. The association between high raffinose intake and reduced stomach cancer risk needs further investigation.

Identification of raffinose family oligosaccharides in processed Rehmannia glutinosa Libosch using matrix-assisted laser desorption/ionization mass spectrometry image combined with machine learning

RATIONALE

Currently, research on oligosaccharides primarily focuses on the physiological activity and function, with a few studies elaborating on the spatial distribution characterization and variation in the processing of Rehmannia glutinosa Libosch. Thus, imaging the spatial distributions and dynamic changes in oligosaccharides during the steaming process is significant for characterizing the metabolic networks of R. glutinosa. It will be beneficial to characterize the impact of steaming on the active ingredients and distribution patterns in different parts of the plant.

METHODS

A highly sensitive matrix-assisted laser desorption/ionization mass spectrometry image (MALDI-MSI) method was used to visualize the spatial distribution of oligosaccharides in processed R. glutinosa. Furthermore, machine learning was used to distinguish the processed R. glutinosa samples obtained under different steaming conditions.

RESULTS

Imaging results showed that the oligosaccharides in the fresh R. glutinosa were mainly distributed in the cortex and xylem. As steaming progressed, the tetra- and pentasaccharides were hydrolyzed and diffused gradually into the tissue section. MALDI-MS profiling combined with machine learning was used to identify the processed R. glutinosa samples accurately at different steaming intervals. Eight algorithms were used to build classification machine learning models, which were evaluated for accuracy, precision, recall, and F1 score. The linear discriminant analysis and random forest models performed the best, with prediction accuracies of 0.98 and 0.97, respectively, and thus can be considered for identifying the steaming durations of R. glutinosa.

CONCLUSIONS

MALDI-MSI combined with machine learning can be used to visualize the distribution of oligosaccharides and identify the processed samples after steaming for different durations. This can enhance our understanding of the metabolic changes that occur during the steaming process of R. glutinosa; meanwhile, it is expected to provide a theoretical reference for the standardization and modernization of processing in the field of medicinal plants.

Natural variation of warm temperature-induced raffinose accumulation identifies TREHALOSE-6-PHOSPHATE SYNTHASE 1 as a modulator of thermotolerance

High-temperature stress limits plant growth and reproduction. Exposure to high temperature, however, also elicits a physiological response, which protects plants from the damage evoked by heat. This response involves a partial reconfiguration of the metabolome including the accumulation of the trisaccharide raffinose. In this study, we explored the intraspecific variation of warm temperature-induced raffinose accumulation as a metabolic marker for temperature responsiveness with the aim to identify genes that contribute to thermotolerance. By combining raffinose measurements in 250 Arabidopsis thaliana accessions following a mild heat treatment with genome-wide association studies, we identified five genomic regions that were associated with the observed trait variation. Subsequent functional analyses confirmed a causal relationship between TREHALOSE-6-PHOSPHATE SYNTHASE 1 (TPS1) and warm temperature-dependent raffinose synthesis. Moreover, complementation of the tps1-1 null mutant with functionally distinct TPS1 isoforms differentially affected carbohydrate metabolism under more severe heat stress. While higher TPS1 activity was associated with reduced endogenous sucrose levels and thermotolerance, disruption of trehalose 6-phosphate signalling resulted in higher accumulation of transitory starch and sucrose and was associated with enhanced heat resistance. Taken together, our findings suggest a role of trehalose 6-phosphate in thermotolerance, most likely through its regulatory function in carbon partitioning and sucrose homoeostasis.

Inhalation powder development without carrier: How to engineer ultra-flying microparticles?

Particle engineering technologies have led to the commercialization of new inhaled powders like PulmoSolTM or PulmoSphereTM. Such platforms are produced by spray drying, a well-known process popular for its versatility, thanks to wide-ranging working parameters. Whereas these powders contain a high drug-loading, we have studied a low-dose case, in optimizing the production of powders with two anti-asthmatic drugs, budesonide and formoterol. Using a Design of Experiments approach, 27 powders were produced, with varying excipient mixes (cyclodextrins, raffinose and maltodextrins), solution concentrations, and spray drying parameters in order to maximize deep lung deposition, measured through fine particle fraction (next generation impactor). Based on statistical analysis, two powders made of hydropropyl-β-cyclodextrin alone or mixed with raffinose and L-leucine were selected. Indeed, the two powders demonstrated very high fine particle fraction (>55%), considerably better than commercially available products. Deep lung deposition has been correlated to very fine particle size and lower microparticles interactions shown by laser diffraction assays at different working pressures, and particle morphometry. Moreover, the two drugs would be predicted to deposit homogeneously into the lung according to impaction studies. Uniform delivery is fundamental to control symptoms of asthma. In this study, we develop carrier-free inhalation powders promoting very efficient lung deposition and demonstrate the high impact of inter-particular interactions intensity on their aerosolization behaviour.

A strategy to promote the convenient storage and direct use of polyhydroxybutyrate-degrading Bacillus sp. JY14 by lyophilization with protective reagents

BACKGROUND

Bioplastics are attracting considerable attention, owing to the increase in non-degradable waste. Using microorganisms to degrade bioplastics is a promising strategy for reducing non-degradable plastic waste. However, maintaining bacterial viability and activity during culture and storage remains challenging. With the use of conventional methods, cell viability and activity was lost; therefore, these conditions need to be optimized for the practical application of microorganisms in bioplastic degradation. Therefore, we aimed to optimize the feasibility of the lyophilization method for convenient storage and direct use. In addition, we incoporated protective reagents to increase the viability and activity of lyophilized microorganisms. By selecting and applying the best protective reagents for the lyophilization process and the effects of additives on the growth and PHB-degrading activity of strains were analyzed after lyophilization. For developing the lyophilization method for protecting degradation activity, it may promote practical applications of bioplastic-degrading bacteria.

RESULTS

In this study, the polyhydroxybutyrate (PHB)-degrading strain, Bacillus sp. JY14 was lyophilized with the use of various sugars as protective reagents. Among the carbon sources tested, raffinose was associated with the highest cell survival rate (12.1%). Moreover, 7% of raffionose showed the highest PHB degradation yield (92.1%). Therefore, raffinose was selected as the most effective protective reagent. Also, bacterial activity was successfully maintained, with raffinose, under different storage temperatures and period.

CONCLUSIONS

This study highlights lyophilization as an efficient microorganism storage method to enhance the applicability of bioplastic-degrading bacterial strains. The approach developed herein can be further studied and used to promote the application of microorganisms in bioplastic degradation.

Discovery of raffinose sulfate as a potential SARS CoV-2 inhibitor via blocking its binding with angiotensin converting enzyme 2

The present study aimed to characterize the possible binding sites on the SARS CoV-2 RBD-ACE2 complex and to highlight sulfated oligosaccharides as potential anti-SARS CoV-2 via inducing RBD-ACE2 complex destabilization and dissociation. By combining pharmacophore-based and structural-based virtual screening approaches we were able to discover raffinose sulfate (RS) as a potential antiviral sulfated oligosaccharide against two SARS CoV-2 variants (i.e., wild type and Omicron) (IC50 = 4.45 ± 0.28 μM and 4.65 ± 0.32 μM, respectively). Upon MD simulation, RS was able to establish stable binding at the RBD-ACE2 interface inducing a rapid dissociation. Accordingly, and by using bio-layer interferometry (BLI) assays, RS was able to significantly weaken the affinity between RBD (of both variants) and ACE2. Additionally, we found that RS has a poor cellular permeability indicating that its interaction with the RBD-ACE2 complex may be the main mechanism by which it mediates its antiviral activity against SARS CoV-2. Despite its proposed interaction with the RBD-ACE2 complex, RS did not show any inhibitory activity against ACE2 catalytic activity. In light of these findings, the RS scaffold can be further developed into a novel anti-SARS CoV-2 drug with improved activity and tolerability in comparison with other sulfated polysaccharides e.g., heparin and heparan.

Raffinose positively regulates maize drought tolerance by reducing leaf transpiration

Drought stress is one of the major constraints of global crop production. Raffinose, a non-reducing trisaccharide, has been considered to regulate positively the plant drought stress tolerance; however, evidence that augmenting raffinose production in leaves results in enhanced plant drought stress tolerance is lacking. The biochemical mechanism through which raffinose might act to mitigate plant drought stress remains unidentified. ZmRAFS encodes Zea mays RAFFINOSE SYNTHASE, a key enzyme that transfers galactose from the galactoside galactinol to sucrose for raffinose production. Overexpression of ZmRAFS in maize increased the RAFS protein and the raffinose content and decreased the water loss of leaves and enhanced plant drought stress tolerance. The biomass of the ZmRAFS overexpressing plants was similar to that of non-transgenic control plants when grown under optimal conditions, but was significantly greater than that of non-transgenic plants when grown under drought stress conditions. In contrast, the percentage of water loss of the detached leaves from two independent zmrafs mutant lines, incapable of synthesizing raffinose, was greater than that from null segregant controls and this phenomenon was partially rescued by supplementation of raffinose to detached zmrafs leaves. In addition, while there were differences in water loss among different maize lines, there was no difference in stomata density or aperture. Taken together, our work demonstrated that overexpression of the ZmRAFS gene in maize, in contrast to Arabidopsis, increased the raffinose content in leaves, assisted the leaf to retain water, and enhanced the plant drought stress tolerance without causing a detectable growth penalty.

Effect of storage time on chemical compositions, physiological and cooking quality characteristics of different rice types

BACKGROUND

Storage affects rice quality significantly. The aim of this study was to investigate the changes in the chemical composition and in the physiological and cooking quality characteristics of three rice types after 1 year storage at 25 °C.

RESULTS

Two japonica, two indica, and two indica-japonica hybrid rice varieties were selected. After storage, the total starch content decreased. The amylose content of japonica, indica, and indica-japonica hybrid rice increased by 9.63%-11.65%, 2.99%-4.67%, and 8.07%-8.97%, respectively, and the fat content decreased by 60.00%-65.00%, 37.21%-46.51%, and 41.67%-42.42%, respectively. The abscisic acid (ABA) and raffinose content decreased after 1 year's storage; the former decreased gradually during the storage and the latter increased by 19.35%-45.45%, 7.02%-10.77%, and 16.13%-28.13%, respectively, after 4 months' storage and then decreased to the lowest level after 1 year's storage. The activity of antioxidant enzymes deceased, which resulted in the increases in fatty acid value and malondialdehyde (MDA). The changes in chemical composition after 1 year storage led to the deterioration of rice cooking quality, which was reflected in the decrease in viscosity and increases in gelatinization temperature and cooked rice hardness.

CONCLUSION

After 1 year's storage, the rice chemical composition changed and physiological and cooking quality characteristics decreased. Compared with japonica and indica-japonica hybrid rice, indica rice was more stable during 1 year storage. This may be due to the higher content of ABA and raffinose in fresh rice. Our findings will provide information for the identification and breeding of storable rice cultivars. © 2022 Society of Chemical Industry.

Mesenchymal Stem Cells Secretions Enhanced ATP Generation on Isolated Islets during Transplantation

The success of islet transplantation in both basic research and clinical settings has proven that cell therapy has the potential to cure diabetes. Islets intended for transplantation are inevitably subjected to damage from a number of sources, including ischemic injury during removal and delivery of the donor pancreas, enzymatic digestion during islet isolation, and reperfusion injury after transplantation in the recipient. Here, we found that protein factors secreted by porcine adipose-tissue mesenchymal stem cells (AT-MSCs) were capable of activating preserved porcine islets. A conditioned medium was prepared from the supernatant obtained by culturing porcine AT-MSCs for 2 days in serum-free medium. Islets were preserved at 4°C in University of Wisconsin solution during transportation and then incubated at 37°C in RPMI-1620 medium with fractions of various molecular weights prepared from the conditioned medium. After treatment with certain fractions of the AT-MSC secretions, the intracellular ATP levels of the activated islets had increased to over 160% of their initial values after 4 days of incubation. Our novel system may be able to restore the condition of isolated islets after transportation or preservation and may help to improve the long-term outcome of islet transplantation.Abbreviations: AT-MSC, adipose-tissue mesenchymal stem cell; Cas-3, caspase-3; DAPI, 4,6-diamidino-2-phenylindole; DTZ, dithizone; ES cell, embryonic stem cell; FITC, fluorescein isothiocyanate; IEQ, islet equivalent; INS, insulin; iPS cell, induced pluripotent stem cell; Luc-Tg rat, luciferase-transgenic rat; PCNA, proliferating cell nuclear antigen; PDX1, pancreatic and duodenal homeobox protein-1; UW, University of Wisconsin; ZO1, zona occludens 1.

Identification of the Toxic Compounds in Camellia oleifera Honey and Pollen to Honey Bees (Apis mellifera)

Identifying the components of Camellia oleifera honey and pollen and conducting corresponding toxicological tests are essential to revealing the mechanism of Camellia oleifera toxicity to honey bees. In this research, we investigated the saccharides and alkaloids in honey, nectar, and pollen from Camellia oleifera, which were compared with honey, nectar, and pollen from Brassica napus, a widely planted flowering plant. The result showed that melibiose, manninotriose, raffinose, stachyose, and lower amounts of santonin and caffeine were found in Camellia oleifera nectar, pollen, and honey but not in B. napus nectar, pollen, and honey. Toxicological experiments indicated that manninotriose, raffinose, and stachyose in Camellia oleifera honey are toxic to bees, while alkaloids in Camellia oleifera pollen are not toxic to honey bees. The toxicity mechanism of oligosaccharides revealed by temporal metabolic profiling is that oligosaccharides cannot be further digested by honey bees and thus get accumulated in honey bees, disturbing the synthesis and metabolism of trehalose, ultimately causing honey bee mortality.

Isolation and Identification of an α-Galactosidase-Producing Lactosphaera pasteurii Strain and Its Enzymatic Expression Analysis

α-Galactosidase (EC 3.2.1.22) refers to a group of enzymes that hydrolyze oligosaccharides containing α-galactoside-banded glycosides, such as stachyose, raffinose, and verbascose. These enzymes also possess great potential for application in sugar production, and in the feed and pharmaceutical industries. In this study, a strain of Lactosphaera pasteurii (WHPC005) that produces α-galactosidase was identified from the soil of Western Hunan, China. It was determined that the optimal temperature and pH for this α-galactosidase were 45 °C and 5.5, respectively. The activity of α-galactosidase was inhibited by K⁺, Al³⁺, Fe³⁺, fructose, sucrose, lactose, galactose, SDS, EDTA, NaCl, and (NH₄)₂SO₄, and enhanced by Ca²⁺, Fe²⁺, Mn², Zn²⁺, glucose, and raffinose. The optimal inducer was raffinose, and the optimal induction concentration was 30 μmol/L. The α-galactosidase gene was cloned using random fragment cloning methods. Sequence analysis demonstrated that the open reading frame of the α-galactosidase gene was 1230 bp, which encodes a putative protein of 409 amino acids in length. Bioinformatics analysis showed that the isoelectric point and molecular weight of this α-galactosidase were 4.84 and 47.40 kD, respectively. Random coils, alpha helixes, and beta turns were observed in its secondary structure, and conserved regions were found in the tertiary structure of this α-galactosidase. Therefore, this α-galactosidase-producing bacterial strain has the potential for application in the feed industry.

Luminal Administration of a Water-soluble Carbon Monoxide-releasing Molecule (CORM-3) Mitigates Ischemia/Reperfusion Injury in Rats Following Intestinal Transplantation

BACKGROUND

The protective effects of carbon monoxide (CO) against ischemia/reperfusion (IR) injury during organ transplantation have been extensively investigated. Likewise, CO-releasing molecules (CORMs) are known to exert a variety of pharmacological activities via liberation of controlled amounts of CO in organs. Therefore, we hypothesized that intraluminal administration of water-soluble CORM-3 during cold storage of intestinal grafts would provide protective effects against IR injury.

METHODS

Orthotopic syngeneic intestinal transplantation was performed in Lewis rats following 6 h of cold preservation in Ringer solution or University of Wisconsin solution. Saline containing CORM-3 (100 µmol/L) or its inactive counterpart (iCORM-3) was intraluminally introduced in the intestinal graft before cold preservation.

RESULTS

Histopathological analysis of untreated and iCORM-3-treated grafts revealed a similar erosion and blunting of the intestinal villi. These changes in the mucosa structure were significantly attenuated by intraluminal administration of CORM-3. Intestinal mucosa damage caused by IR injury led to considerable deterioration of gut barrier function 3 h postreperfusion. CORM-3 significantly inhibited upregulation of proinflammatory mRNA levels, ameliorated intestinal morphological changes, and improved graft blood flow and mucosal barrier function. Additionally, CORM-3-treated grafts increased recipient survival rates. Pharmacological blockade of soluble guanylyl cyclase activity significantly reversed the protective effects conferred by CORM-3, indicating that CO partially mediates its therapeutic actions via soluble guanylyl cyclase activation.

CONCLUSIONS

Our study demonstrates that luminally delivered CORM-3 provides beneficial effects in cold-stored rat small intestinal grafts and could be an attractive therapeutic application of CO in the clinical setting of organ preservation and transplantation.

Changes in Metabolic Profiles of Pea (Pisum sativum L.) as a Result of Repeated Short-Term Soil Drought and Subsequent Re-Watering

The metabolic re-arrangements of peas (Pisum sativum L.) under soil drought and re-watering are still not fully explained. The search for metabolic markers of the stress response is important in breeding programs, to allow for the selection drought-resistant cultivars. During the present study, changes in the polar metabolite content in pea plant shoots were measured under repeated short-term soil drought and subsequent re-watering. A gas chromatograph, equipped with a mass spectrometer (GC-MS), was used for the metabolite profiling of pea plants during their middle stage of vegetation (14-34 days after sowing, DAS). The major changes occurred in the concentration of amino acids and some soluble carbohydrates. Among them, proline, γ-aminobutyric acid (GABA), branched-chain amino acids, hydroxyproline, serine, myo-inositol, and raffinose were accumulated under each soil drought and decreased after re-watering. Besides, the obtained results show that the first drought/re-watering cycle increased the ability of pea plants to restore a metabolic profile similar to the control after the second similar stress. The accumulation of proline seems to be an important part of drought memory in pea plants. However, confirmation of this suggestion requires metabolite profiling studies on a broader spectrum of pea cultivars.

Raffinose accumulation and preferential allocation of carbon (14 C) to developing leaves impart salinity tolerance in sugar beet

Sugar beet is a salt-tolerant crop that can be explored for crop production in degraded saline soils. Seeds of multigerm genotypes LKC-2006 (susceptible) and LKC-HB (tolerant) were grown in 150 mM NaCl, from germination to 60 days after sowing, to decipher the mechanism of salinity tolerance at the vegetative stage. The biomass of the root and leaf were maintained in the tolerant genotype, LKC-HB, under saline conditions. Na⁺ /K⁺ ratios were similar in roots and leaves of LKC-HB, with lower values under salinity compared to LKC 2006. Infrared temperatures were 0.96°C lower in LKC-HB than in LKC-2006, which helped regulate the leaf water status under stressed conditions. Pulse-chase experiment showed that ¹⁴ C photosynthate was preferentially allocated towards the development of new leaves in the tolerant genotype. The sugar profile of leaves and roots showed accumulation of raffinose in leaves of LKC-HB, indicating a plausible role in imparting salinity tolerance by serving as an osmolyte or scavenger. The molecular analysis of the genes responsible for raffinose synthesis revealed an 18-fold increase in the expression of BvRS2 in the tolerant genotype, suggesting its involvement in raffinose synthesis. Our study accentuated that raffinose accumulation in leaves is vital for inducing salinity tolerance and maintenance of shoot dry weight in sugar beet.

The effect of blood cells retained in rat livers during static cold storage on viability outcomes during normothermic machine perfusion

In transplantation, livers are transported to recipients using static cold storage (SCS), whereby livers are exposed to cold ischemic injury that contribute to post-transplant risk factors. We hypothesized that flushing organs during procurement with cold preservation solutions could influence the number of donor blood cells retained in the allograft thereby exacerbating cold ischemic injury. We present the results of rat livers that underwent 24 h SCS after being flushed with a cold University of Wisconsin (UW) solution versus room temperature (RT) lactated ringers (LR) solution. These results were compared to livers that were not flushed prior to SCS and thoroughly flushed livers without SCS. We used viability and injury metrics collected during normothermic machine perfusion (NMP) and the number of retained peripheral cells (RPCs) measured by histology to compare outcomes. Compared to the cold UW flush group, livers flushed with RT LR had lower resistance, lactate, AST, and ALT at 6 h of NMP. The number of RPCs also had significant positive correlations with resistance, lactate, and potassium levels and a negative correlation with energy charge. In conclusion, livers exposed to cold UW flush prior to SCS appear to perform worse during NMP, compared to RT LR flush.

Risk Factors for Development of Biliary Stricture After Liver Transplant in Adult Patients: A Single-Center Retrospective Study

Identification of risk factors for biliary stricture after liver transplant and its potential prevention is crucial to improve the outcomes and reduce the complications. We retrospectively analyzed donor and recipient characteristics with intraoperative and postoperative parameters to identify the risk factors for development of post-transplant anastomotic and nonanastomotic biliary strictures with additional analysis of the time onset of those strictures. A total of 412 patients were included in this study. Mean (SD) follow-up time was 79 (35) months (range, 1-152 months). Biliary stricture was diagnosed in 84 patients (20.4%). Multivariate analysis indicated that postoperative biliary leakage (odd ratio [OR], 3.94; P = .001), acute cellular rejection (OR, 3.05; P < .001), donor age older than 47.5 years (OR, 2.05; P = .032), preoperative recipient platelet value < 77.5 × 10³/mL (OR, 1.91; P = .023), University of Wisconsin solution (OR, 1.73; P = .041)), recipient male sex (OR, 1.78; P = .072), portal/arterial flow ratio > 4 (OR, 1.76; P = .083), and intraoperative bleeding > 2850 mL (OR, 1.70; P = .053) were independent risk factors for biliary stricture regardless of the time of their appearance. Multiple risk factors for biliary stricture were determined in this study. Some of these risk factors are preventable, and implementation of strategies to eliminate some of those factors should reduce the development of post-transplant biliary stricture.

ZmAGA1 Hydrolyzes RFOs Late during the Lag Phase of Seed Germination, Shifting Sugar Metabolism toward Seed Germination Over Seed Aging Tolerance

Raffinose family oligosaccharides (RFOs) are accumulated during the late stage of seed development and hydrolyzed during seed germination. The process of raffinose hydrolysis during seed germination and how this process affects seed vigor remains unknown. We report here that maize alkaline α-galactosidase 1 (ZmAGA1) protein is translationally induced and is capable of hydrolyzing RFOs as well as a precursor, galactinol, during seed germination. Constitutively overexpressing ZmAGA1 in Arabidopsis decreased both RFOs and galactinol contents of mature, desiccated, and 30 hours after imbibition (HAI) seeds, yet enhanced the seed germination percentage under either salt or somewhat osmotic-stress conditions at earlier times during the time course. However, ZmAGA1 overexpression also decreased the seed aging tolerance of mature, desiccated seeds as compared with wild type (WT) or those overexpressing GFP. Compared to that of WT control seeds, the atsip2 (mutant of Arabidopsis AtSIP2 (seed imbibition protein 2, encoding alkaline α-galactosidase)) seeds have similar RFOs and galactinol contents in mature, desiccated seeds but significantly increased the amount of these metabolites at 30 HAI. This retention of RFOs and galactinol in atsip2 results in seeds that exhibit lowered seed germination percentage under either salt or osmotic stress conditions, and yet, increased seed aging tolerance relative to WT. Similarly, when maize seeds were imbibed in the presence of a specific α-galactosidase inhibitor (1-deoxygalactonojirimycin) as compared to those imbibed in water, greater amounts of raffinose and galactinol were detected; the seeds exhibited decreased seed germination percentages but increased seed aging tolerance. Taken together, these data suggest that both maize seed germination and seed aging tolerance can be simultaneously regulated through careful temporal manipulation of ZmAGA1 expression.

Transcriptomic and Metabolic Analysis of Fruit Development and Identification of Genes Involved in Raffinose and Hydrolysable Tannin Biosynthesis in Walnuts

Walnut (Juglans regia L.) is an important fruit tree with high nutrition in its nuts. Here, the development of walnut fruits was monitored, and nine biological samples at five developmental stages were collected and analyzed by transcriptomic and metabolic assays. Many phenolic metabolites accumulated in the peel of mature fruits, while lipids, carbohydrates, and amino acids and their derivatives mainly accumulated in the kernel. Fatty acid biosynthesis occurred at 13 weeks after pollination, and photosynthesis might occur in the exocarp of walnuts. By coexpression analysis of the transcriptome and metabolome, genes responsible for some metabolic pathways were predicted. Three genes encoding shikimate dehydrogenases (SDHs) that convert 3-dehydroshikimic acid to gallic acid (GA) and four genes encoding UDP-glycosyltransferase (UGT) that convert GA to β-glucogallin in the biosynthesis of hydrolysable tannins (HTs) were selected for functional confirmation. These three SDH genes were then expressed in Escherichia coli, and their recombinant proteins showed GA formation activity. Moreover, heterologous expression of the three SDH and four UGT genes in poplar hairy roots also showed a significant increase in GA and β-glucogallin accumulation, respectively. Taken together, we have provided an overview of walnut fruit development and uncovered genes involved in HT biosynthesis.

Suppression of Inflammation-Associated Kidney Damage Post-Transplant Using the New PrC-210 Free Radical Scavenger in Rats

Allograft kidney transplantation, which triggers host cellular- and antibody-mediated rejection of the kidney, is a major contributor to kidney damage during transplant. Here, we asked whether PrC-210 would suppress damage seen in allograft kidney transplant. Brown Norway (BN) rat kidneys were perfused in situ (UW Solution) with or without added 30 mM PrC-210, and then immediately transplanted into Lewis (LEW) rats. 20 h later, the transplanted BN kidneys and LEW rat plasma were analyzed. Kidney histology, and kidney/serum levels of several inflammation-associated cytokines, were measured to assess mismatch-related kidney pathology, and PrC-210 protective efficacy. Twenty hours after the allograft transplants: (i) significant histologic kidney tubule damage and mononuclear inflammatory cell infiltration were seen in allograft kidneys; (ii) kidney function metrics (creatinine and BUN) were significantly elevated; (iii) significant changes in key cytokines, i.e., TIMP-1, TNF-alpha and MIP-3A/CCL20, and kidney activated caspase levels were seen. In PrC-210-treated kidneys and recipient rats, (i) kidney histologic damage (Banff Scores) and mononuclear infiltration were reduced to untreated background levels; (ii) creatinine and BUN were significantly reduced; and (iii) activated caspase and cytokine changes were significantly reduced, some to background. In conclusion, the results suggest that PrC-210 could provide broadly applicable organ protection for many allograft transplantation conditions; it could protect transplanted kidneys during and after all stages of the transplantation process-from organ donation, through transportation, re-implantation and the post-operative inflammation-to minimize acute and chronic rejection.

Importance of inositols and their derivatives in cowpea under root dehydration: An omics perspective

This work presents a robust analysis of the inositols (INSs) and raffinose family oligosaccharides (RFOs) pathways, using genomic and transcriptomic tools in cowpea under root dehydration. Nineteen (~70%) of the 26 scrutinized enzymes presented transcriptional up-regulation in at least one treatment time. The transcriptional orchestration allowed categorization of the analyzed enzymes as time-independent (those showing the same regulation throughout the assay) and time-dependent (those showing different transcriptional regulation over time). It is suggested that up-regulated time-independent enzymes (INSs: myo-inositol oxygenase, inositol-tetrakisphosphate 1-kinase 3, phosphatidylinositol 4-phosphate 5-kinase 4-like, 1-phosphatidylinositol-3-phosphate 5-kinase, phosphoinositide phospholipase C, and non-specific phospholipase C; RFOs: α-galactosidase, invertase, and raffinose synthase) actively participate in the reorganization of cowpea molecular physiology under the applied stress. In turn, time-dependent enzymes, especially those up-regulated in some of the treatment times (INSs: inositol-pentakisphosphate 2-kinase, phosphatidylinositol 4-kinase, phosphatidylinositol synthase, multiple inositol polyphosphate phosphatase 1, methylmalonate-semialdehyde dehydrogenase, triosephosphate isomerase, myo-inositol-3-phosphate synthase, phosphatidylinositol 3,4,5-trisphosphate 3-phosphatase and protein-tyrosine-phosphatase, and phosphatidylinositol 3-kinase; RFOs: galactinol synthase) seem to participate in fine-tuning of the molecular physiology, helping the cowpea plants to acclimatize under dehydration stress. Not all loci encoding the studied enzymes were expressed during the assay; most of the expressed ones exhibited a variable transcriptional profile in the different treatment times. Genes of the INSs and RFOs pathways showed high orthology with analyzed Phaseoleae members, suggesting a relevant role within this legume group. Regarding the promoter regions of INSs and RFOs genes, some bona fide cis-regulatory elements were identified in association with seven transcription factor families (AP2-EFR, Dof-type, MADS-box, bZIP, CPP, ZF-HD, and GATA-type). Members of INSs and RFOs pathways potentially participate in other processes regulated by these proteins in cowpea.

Reduction of Renal Preservation/Reperfusion Injury by Controlled Hyperthermia During Ex Vivo Machine Perfusion

The possible reno-protective effect of a controlled brief heat-shock treatment during isolated ex vivo machine perfusion of donor grafts prior to reperfusion should be investigated in a primary in vitro study. Porcine kidneys (n = 14) were retrieved after 20 minutes of cardiac standstill of the donor and subjected to 20 hours of static cold storage in University of Wisconsin solution. Prior to reperfusion, kidneys were subjected to 2 hours of reconditioning machine perfusion with gradual increase in perfusion temperature up to 35°C. In half of the kidneys (n = 7), a brief hyperthermic impulse (10 minutes perfusion at 42°C) was implemented in the machine perfusion period. Functional recovery of the grafts was observed upon normothermic reperfusion in vitro. Hyperthermic treatment resulted in a 50% increase of heat shock protein (HSP) 70 and HSP 27 mRNA and was accompanied by ~ 50% improvement of tubular re-absorption of sodium and glucose upon reperfusion, compared with the controls. Furthermore, renal loss of aspartate aminotransferase was significantly reduced to one-third of the controls as was urinary protein loss, evaluated by the albumin to creatinine ratio. It is concluded that ex vivo heat-shock treatment seems to be an easily implementable and promising option to enhance renal self-defense machinery against reperfusion injury after preservation that merits further investigation in preclinical models.

Effect of broad-spectrum biofilm inhibitor raffinose, a plant galactoside, on the inhibition of co-culture biofilm on the microfiltration membrane

A membrane bioreactor (MBR) integrates process such as membrane filtration and biological treatment of activated sludge. However, organic, inorganic and biological matters cause membrane fouling, which seriously affects membrane performance. The goal of this study was to evaluate the biofouling inhibition capacity of raffinose during the MBR process. The results showed that 0-1,000 μM raffinose significantly reduced the formation of the P. aeruginosa and S. aureus co-culture biofilm by about 25-52 % in a concentration-dependent manner. In addition, the effect of raffinose on the microfiltration membrane biofilm was tested in a flow reactor and lab-scale MBR unit. The results showed that the co-culture biofilm and transmembrane pressure were decreased by raffinose treatment compared to those by furanone C-30 treatment. These results clearly demonstrated that raffinose, broad-spectrum biofilm inhibitor, inhibits biofilm formation in mixed cultures and could be used to mitigate biofouling in MBR processes.

Effects of soybean oligosaccharide, stachyose, and raffinose on growth performance and cecal microbiota in broiler chickens

This study was conducted to examine the effects of soybean oligosaccharide, stachyose, and raffinose on growth performance and cecal microbiota in broiler chickens. Three-hundred 1-day-old Arbor Acres broiler chickens were randomly assigned to five dietary treatments: a basal diet (control diet); diets supplemented with soybean oligosaccharide, stachyose, or raffinose at levels of 0.6% total sugar content; and diet with soybean meals (positive control). Results showed that feed-to-gain ratio (F/G) was improved (p < 0.05) in broiler chickens that received stachyose, but not raffinose, while addition of soybean oligosaccharide to the diet significantly (p < 0.05) resulted in decreases in the average daily feed intake (ADFI) and average daily gain (ADG). Supplementation with soybean oligosaccharide, stachyose, or raffinose had a positive effect (p < 0.05) on the nutrient digestibility, but not on the blood immune parameters (p > 0.05). The results of the gene sequencing indicated that, at the family level, Ruminococcaceae, Lachnospiraceae, and Lactobacillaceae were comparatively present in all the treatments but the cecal microbial composition was changed after dietary addition of different oligosaccharides. Our study had led to a greater understanding of prebiotic effects of these oligosaccharides on growth and intestinal health.

Influence of 4 preservation solutions on ICU stay, graft and patient survival following liver transplantation

OBJECTIVE

The goal of this study was to evaluate the prognostic role of four preservation solutions in liver transplantation (LT).

PATIENTS AND METHODS

This is a retrospective study originating from 22 French centers performing LT, registered in the prospective databank of the Cristal Biomedicine Agency between 2008 and 2013. The preservation solutions used were Celsior (CS), Institut Georges Lopez (IGL)-1, Solution de Conservation des Organes et des Tissus (SCOT) 15 and University of Wisconsin (UW) solutions. Exclusion criteria were preservation with unknown or inhomogeneous solutions, or Histidine-tryptophan-ketoglutarate (HTK) solution (representing only 3% of LT). Patient survival was the main endpoint. Secondary endpoints were graft survival and duration of stay in intensive care.

RESULTS

Of 6347 LT performed, 4928 were included in this study, for which the distribution of preservation solution was CS (30%), IGL-1 (44%), SCOT 15 (10%) and UW (16%). Patient survival was 86%, 80% and 74% at 1, 3 and 5 years after LT, respectively, without any statistically significant difference between the four solutions (P=0.78). Graft survival was 82%, 75% and 69% at 1, 3 and 5 years after LT, respectively, without any statistically significant difference between the four solutions (P=0.80). Duration of intensive care was different according to the solution used in univariate analysis (P<0.001), but this effect disappeared in multivariate analysis when the center performing the transplantation was accounted for.

CONCLUSION

The type of preservation solution used (CS, IGL-1, SCOT 15 or UW) did not have any influence on patient or graft survival after LT.

Time-dependent Effects of Pressure during Preservation of Rat Hearts in an Isochoric System at Subfreezing Temperatures

BACKGROUND

Isochoric freezing systems enable ice-free preservation of biological matter at subfreezing temperatures under the increased hydrostatic pressure.

OBJECTIVE

To examine the effects of pressure and exposure period on rat hearts preserved in an isochoric chamber.

MATERIALS AND METHODS

Rat hearts were preserved in the UW solution in isochoric chambers at temperatures from -2°C to -8°C and pressure from the atmospheric level to 78 MPa for up to eight hours, with and without the addition of glycerol. Hearts were evaluated via Langendorff perfusion and HE histology.

RESULTS

Hearts were compromised quickly as pressure increased, suggesting an acute time-pressure sensitivity. With the addition of 1 M glycerol, which reduces the pressure experienced at a given temperature, the survival time at -4°C was doubled.

CONCLUSION

The enhanced hydrostatic pressure encountered during isochoric preservation yields time-dependent negative effects on the heart, which can potentially be alleviated by the addition of a cryoprotectant.

Ischemic Type Biliary Lesions in Histidine-Tryptophan-Ketoglutarate (HTK) Preserved Liver Grafts

Ischemic type biliary lesions lead to considerable morbidity following orthotopic liver transplantation. The exact pathogenesis is unknown. One major hypothesis is that insufficient perfusion of the arterial vessels of the biliary tree, especially under perfusion with the high viscous University of Wisconsin solution, might be responsible for ischemic type biliary lesions. Due to low viscosity, HTK solution is reported to have a lower incidence of biliary complications. However, there is no data concerning ischemic type biliary lesions in HTK preserved livers. In this paper we report our results after orthotopic liver transplantation with special regard to ischemic type biliary lesions in liver grafts preserved with HTK solution. Between 09/1997 and 01/2005 300 liver transplantations were performed in our center. Thirty-two (10.7%) liver grafts were preserved with HTK solution, 268 (89.3%) were preserved with UW solution. Six and 43 grafts showed ischemic type biliary lesions after orthotopic liver transplantation in HTK- (18.8%) and UW- (16.0%) groups, respectively (p=0.696). There was no statistical significant difference between the two groups. Donor related factors, recipient age, indication for transplantation, transplantation technique, immunosuppression and ischemia time were comparable in both groups.

Ischemic type biliary lesions occurred with the same frequency in HTK preserved livers compared to UW preserved organs. We suggest that low viscosity of the preservation fluid by itself does not guarantee reliable perfusion of the small arteries of a liver graft and a pressure perfusion might be beneficial even in HTK solution.

Perfusion of isolated rat kidney with Mesenchymal Stromal Cells/Extracellular Vesicles prevents ischaemic injury

Kidney donation after circulatory death (DCD) is a less than ideal option to meet organ shortages. Hypothermic machine perfusion (HMP) with Belzer solution (BS) improves the viability of DCD kidneys, although the graft clinical course remains critical. Mesenchymal stromal cells (MSC) promote tissue repair by releasing extracellular vesicles (EV). We evaluated whether delivering MSC-/MSC-derived EV during HMP protects rat DCD kidneys from ischaemic injury and investigated the underlying pathogenic mechanisms. Warm ischaemic isolated kidneys were cold-perfused (4 hrs) with BS, BS supplemented with MSC or EV. Renal damage was evaluated by histology and renal gene expression by microarray analysis, RT-PCR. Malondialdehyde, lactate, LDH, glucose and pyruvate were measured in the effluent fluid. MSC-/EV-treated kidneys showed significantly less global ischaemic damage. In the MSC/EV groups, there was up-regulation of three genes encoding enzymes known to improve cell energy metabolism and three genes encoding proteins involved in ion membrane transport. In the effluent fluid, lactate, LDH, MDA and glucose were significantly lower and pyruvate higher in MSC/EV kidneys as compared with BS, suggesting the larger use of energy substrates by MSC/EV kidneys. The addition of MSC/EV to BS during HMP protects the kidney from ischaemic injury by preserving the enzymatic machinery essential for cell viability and protects the kidney from reperfusion damage.

Importance of pH in Resuspension Media on Viability of Hepatocytes Preserved in University of Wisconsin Solution

The effect of different pH of resuspension media on the viability of hepatocytes preserved (for 96 h at 4°C) in University of Wisconsin solution (UW solution) was analyzed. After this cold resuspension media storage, we evaluated the rewarming step (incubation time 120 min at 37°C) using different pH levels (6.80, 7.00, 7.20, and 7.40). Cell viability assessed by trypan blue exclusion (TBE) showed a significant difference (p < 0.05) for cells incubated at pH = 7.20. For instance, TBE expressed as percent of change was 78.1 ± 1.4 compared with cells tested at other pH (pH = 6.80, TBE = 44.2 ± 9.5; pH = 7.00, TBE = 66.5 ± 1.1 and pH = 7.40, TBE = 62.0 ± 1.4). We also evaluated the capacity of these cells both to maintain potassium content (0.509 ± 0.230 μEq. K+/106 cells) and to synthesize urea (5.36 ± 1.81 μmol Urea/106 cells). These results were compared with those obtained from freshly isolated non preserved hepatocytes (0.518 ± 0.060 μEq. K+/106 cells and 5.91 ± 0.43 μmol Urea/106 cells). The results show that viability is pH dependent and suggest that when resuspension media were used, the viability of hepatocytes was improved after 96 h of cold storage.

Short-Term Hypothermic Preservation of Porcine Hepatocyte Spheroids using uw Solution

The feasibility of University of Wisconsin (UW) solution in short-term hypothermic preservation of porcine hepatocyte spheroids was investigated, because they have great potential in bioartificial liver (BAL) systems. Porcine hepatocyte spheroids preserved for 3 days expressed almost comparable levels of albumin secretion as those without preservation, during 8 subsequent days of recultivation in continuous rotational culture, whereas isolated single cells did not reorganize into spheroids and completely lost their function in recultivation. Although for 3-day–preserved spheroids, the albumin secretion was lowered immediately after recultivation (Days 0–2), it was completely restored to that of nonpreserved ones. The function was completely lost in recultivation for 7-day–preserved ones. These results demonstrate that reorganization into spheroids is effective in preventing the functional loss of porcine hepatocytes occurring in hypothermic preservation, and that spheroid formation should precede the preservation as long as spheroid culture is finally used in BAL systems. Also, porcine hepatocyte spheroids are shown to be satisfactory stored in UW solution up to 3 days without significant cellular or functional loss.

Machine perfusion enhances hepatocyte isolation yields from ischemic livers

BACKGROUND

High-quality human hepatocytes form the basis of drug safety and efficacy tests, cell-based therapies, and bridge-to-transplantation devices. Presently the only supply of cells derives from an inadequate pool of suboptimal disqualified donor livers. Here we evaluated whether machine perfusion could ameliorate ischemic injury that many of these livers experience prior to hepatocyte isolation.

METHODS

Non-heparinized female Lewis rat livers were exposed to an hour of warm ischemia (34°C) and then perfused for 3h. Five different perfusion conditions that utilized the cell isolation apparatus were investigated, namely: (1) modified Williams Medium E and (2) Lifor, both with active oxygenation (95%O(2)/5%CO(2)), as well as (3) Lifor passively oxygenated with ambient air (21%O(2)/0.04%CO(2)), all at ambient temperatures (20 ± 2°C). At hypothermic temperatures (5 ± 1°C) and under passive oxygenation were (4) University of Wisconsin solution (UW) and (5) Vasosol. Negative and positive control groups comprised livers that had ischemia (WI) and livers that did not (Fresh) prior to cell isolation, respectively.

RESULTS

Fresh livers yielded 32 ± 9 million cells/g liver while an hour of ischemia reduced the cell yield to 1.6 ± 0.6 million cells/g liver. Oxygenated Williams Medium E and Lifor recovered yields of 39 ± 11 and 31 ± 2.3 million cells/g liver, respectively. The passively oxygenated groups produced 15 ± 7 (Lifor), 13 ± 7 (Vasosol), and 10 ± 6 (UW)million cells/g liver. Oxygenated Williams Medium E was most effective at sustaining pH values, avoiding the accumulation of lactate, minimizing edematous weight gain and producing bile during perfusion.

CONCLUSIONS

Machine perfusion results in a dramatic increase in cell yields from livers that have had up to an hour of warm ischemia, but perfusate choice significantly impacts the extent of recovery. Oxygenated Williams Medium E at room temperature is superior to Lifor, UW and Vasosol, largely facilitated by its high oxygen content and low viscosity.

Coconut water solutions for the preservation of spleen, ovary, and skin autotransplants in rats

BACKGROUND

The purpose of this study was to evaluate the efficacy of coconut water in the preservation of spleen, ovary, and skin autotransplantations in rats.

METHODS

Fifty female Wistar rats were divided randomly into 5 groups on the basis of the following tissue graft preservation solutions: group 1, lactated Ringer's; group 2, Belzer's solution; group 3, mature coconut water; group 4, green coconut water; and group 5, modified green coconut water. In group 5, the green coconut water solution was modified to obtain the same electrolyte composition as Belzer's solution. The spleen, ovaries, and a skin fragment were removed from each animal, stored for 6 hours in one of the solutions, and then re-implanted. The recoveries of tissue functions were assessed 90 days after surgery by means of spleen scintigraphy and blood tests. The implanted tissues were collected for histological analyses.

RESULTS

Higher immunoglobulin G levels were observed in the animals of group 5 than in the animals of group 1. Differences in follicle-stimulating hormone levels were observed between groups 1 and 2 (P < .001), between groups 4 and 2 (P = .03), and between groups 5 and 2 (P = .01). The spleen scintigraphy results did not differ among the groups. The ovarian tissue was better preserved in the mature coconut water group (P < .007).

CONCLUSIONS

Solutions containing coconut water allowed for the preservation of the spleen, ovaries, and skin for 6 hours, and the normal functions of these tissues were maintained in rats.

[Outcomes using two preservation solutions (UW/HTK) in liver transplantation from brain death donors]

BACKGROUND

Preservation solutions are critical for organ transplantation. In liver transplant (LT), the solution developed by the University Of Wisconsin (UW) is the gold-standard to perfuse deceased brain death donor (DBD) grafts. Histidine-Tryptophan-Ketoglutarate (HTK), formerly a cardioplegic infusion, has been also used in solid organ transplantation.

AIM

To compare the outcomes of LT in our center using either HTK or UW solution.

PATIENTS AND METHODS

Retrospective study including 93 LT DBD liver grafts in 89 patients transplanted between March 1994 and July 2010. Forty-eight grafts were preserved with UW and 45 with HTK. Donor and recipient demographics, total infused volume, cold ischemia time, post-reperfusion biopsy, liver function tests, incidence of biliary complications, acute rejection and 12-month graft and patient survival were assessed. Preservation solution costs per liver graft were also recorded.

RESULTS

Donor and recipient demographics were similar. When comparing UW and HTK, no differences were observed in cold ischemia time (9.6 ± 3 and 8.7 ± 2 h respectively, p = 0.23), biliary complications, the incidence of acute rejection, primary or delayed graft dysfunction. Histology on post-reperfusion biopsies revealed no differences between groups. The infused volume was significantly higher with HTK than with UW (9 (5-16) and 6 (3-11) l, p < 0.001). The cost per procurement was remarkably lower using HTK.

CONCLUSIONS

Perfusion of DBD liver grafts with HTK is clinically equivalent to UW, with a significant cost reduction.

Single centre experience of hypothermic machine perfusion of kidneys from extended criteria deceased heart-beating donors: a comparative study

INTRODUCTION

Kidneys from extended criteria donors are associated with higher rates of delayed graft function (DGF). Hypothermic machine perfusion (MP) for storage is associated with more favourable outcomes.

METHODS

A retrospective analysis was performed in 93 patients where the kidney was stored using hypothermic MP (LifePort(®)) and compared to an age-matched control group where the kidney was stored in cold static storage (CSS) using University of Wisconsin solution.

RESULTS

Median age was similar in both groups (59.2 years in MP vs 59.9 years in CSS, p = 0.5598). Mean cold storage time was 15.6 h in MP vs 17.9 h in CSS. Post transplant mean serum creatinine was as follows; MP group-144.7 μmol/L at 1 month; 138.3 μmol/L at 3 months and 129.5 μmol/L at 12 months. In the CSS group-163 μmol/L at 1 month; 154.9 μmol/L at 3 months and 140.2 μmol/L at 12 months. There was a statistically significant difference at 1 month (p = 0.0096) and 3 months (p = 0.0236). DGF was defined as the need for haemodialysis within 7 days post transplant. In the MP group, DGF occurred in 17.2 % patients with mean of 6 days (range 1-18). In the CSS group, 25.8 % patients with mean of 8.1 days (range 3-25). One-year graft survival rate was better in the MP group (97.85 vs 96.77 %).

CONCLUSION

Our experience to date recommends the use of hypothermic MP for storage of kidneys from extended criteria deceased heart-beating donors.

Non-invasive magnetic resonance imaging in rats for prediction of the fate of grafted kidneys from cardiac death donors

The main objective of this study was to assess cardiac death (CD) kidney grafts before transplantation to determine whether blood oxygen level-dependent (BOLD) and diffusion MRI techniques can predict damage to these grafts after transplantation. We assessed CD kidney tissue by BOLD and diffusion MRI. We also examined pathological and gene expression changes in CD kidney grafts before and after transplantation. Although there was significantly more red cell congestion (RCC) in the inner stripe of the outer medulla (IS) in both 1 h after cardiac death (CD1h) and CD2h kidneys destined for grafts before transplantation compared with CD0h (p<0.05), CD2h, but not CD1h, kidney grafts had significantly different RCC in the IS 2 days after transplantation (p<0.05). Consistent with these pathological findings, tissue plasminogen activator (tPA) gene expression was increased only in the cortex and medulla of CD2h kidney grafts after transplantation. BOLD MRI successfully and non-invasively imaged and quantified RCC in the IS in both CD1h and CD2h kidney grafts (p<0.05). Diffusion MRI also non-invasively assessed increased the apparent diffusion coefficient in the IS and decreased it in the outer stripe (OS) of CD2h grafts, in concordance with interstitial edema in the IS and tubule cellular edema in the OS. These two types of edema in the outer medulla could explain the prolonged RCC in the IS only of CD2h kidney grafts, creating part of a vicious cycle inhibiting red cells coming out of capillary vessels in the IS. Perfusion with University of Wisconsin solution before MRI measurements did not diminish the difference in tissue damage between CD1h and CD2h kidney grafts. BOLD and diffusion MRI, which are readily available non-invasive tools for evaluating CD kidney grafts tissue damage, can predict prolonged organ damage, and therefore the outcome, of transplanted CD kidney grafts.

[Donor heart preservation with University of Wisconsin solution and immunosuppressive therapy with drip-infusion of tacrolimus]

Clinical approach for heart transplantation in Kyushu University Hospital Heart Center about donor heart preservation and immunosuppressive therapy is reviewed. University of Wisconsin solution has been used for donor heart preservation as the 1st-line solution, because left ventricular function after both 6-hour and 24-hour preservation with University of Wisconsin solution was superior to that with Celsior solution on the cross-circulated rabbit heart preparation model. Donor hearts are arrested by the extracellular-type cardioplegia to prevent coronary vasoconstriction associated with preservation in University of Wisconsin solution. Tacrolimus has been used as immunosuppressive agent. Drip-infusion of tacrolimus (0.02 mg/kg per day) is started immediately after heart transplantation aiming at definitive blood level control.

Improved hypothermic short-term storage of isolated mouse islets by adding serum to preservation solutions

Preserving isolated islets at low temperature appears attractive because it can keep islet quantity comparable to freshly isolated islets. In this study, we evaluated the effect of serum as an additive to preservation solutions on islet quality after short-term hypothermic storage. Isolated mouse islets were preserved at 4°C in University of Wisconsin solution (UW) alone, UW with serum, M-Kyoto solution (MK) alone or MK with serum. We then assessed islet quantity, morphology, viability and function in vitro as well as in vivo. Islet quantity after storage in all four solutions was well maintained for up to 120 h. However, islets functioned for different duration; glucose-stimulated insulin release assay revealed that the duration was 72 h when islets were stored in UW with serum and MK with serum, but only 24 h in UW alone, and the islet function disappeared immediately in MK alone. Viability assay confirmed that more than 70% islet cells survived for up to 48 h when islets are preserved in UW with serum and MK with serum, but the viability decreased rapidly in UW alone and MK alone. In in vivo bioassays using 48-h preserved isogeneic islets, all recipient mice restored normal blood glucose concentrations by transplants preserved in UW with serum or MK with serum, whereas 33.3% recipients and no recipient restored diabetes by transplants preserved in UW alone and in MK alone respectively. Adding serum to both UW and MK improves their capability to store isolated islets by maintaining islet functional viability.

Protective effect of Lifor solution in experimental renal ischemia-reperfusion injury

BACKGROUND

Improved kidney preservation methods are needed to reduce ischemia-reperfusion (IR) injury in kidney allografts. Lifor is an artificial preservation solution comprised of nutrients, growth factors, and a non-protein oxygen and nutrient carrier. The current study compared the effectiveness of Lifor to University of Wisconsin solution (UW) in protecting rat kidneys from warm IR and cold storage injury.

MATERIALS AND METHODS

In a warm IR model, rat kidneys were perfused in situ with either saline, UW, or Lifor for 45 min. Renal function and histology were assessed 24 h later. In a cold IR model, kidney slices were cold-stored in saline, UW, or Lifor at 4°C. Kidney injury was assessed by the release of lactate dehydrogenase (LDH) and immunoblot analysis for cleaved caspase-3.

RESULTS

Lifor perfusion significantly mitigated renal dysfunction and tubular injury at 24 h compared with saline or UW. Lifor and UW prevented LDH release in hypoxic kidney slices in vitro, however activation of caspase-3 following hypoxia-reoxygenation was attenuated only with Lifor. Cold storage with Lifor or UW significantly decreased LDH release from kidney slices or normal rat kidney cells in comparison to storage in saline or culture media. After 24 h of cold storage there was a significant decrease in cleaved caspase-3 in Lifor stored slices compared that seen following cold storage in saline or UW solution.

CONCLUSIONS

Lifor solution mitigates both warm and cold renal IR and appears to provide greater protection from apoptosis compared with UW solution.

Cryopreservation of mammalian oocytes by using sugars: Intra- and extracellular raffinose with small amounts of dimethylsulfoxide yields high cryosurvival, fertilization, and development rates

Accumulation of intra- and extracellular sugars such as trehalose, glucose, and raffinose is central to survival strategies of a variety of organisms coping with extreme conditions including freezing and almost complete drying. The objective of the present study was to investigate the potential application of intra- and extracellular raffinose in combination with low concentrations of dimethylsulfoxide (Me(2)SO) to mammalian oocyte cryopreservation. To this end, the fertilization and embryonic development of cryopreserved metaphase II (M II) mouse oocytes were studied in comparison to unfrozen controls. For cryopreservation, M II oocytes were microinjected with 0.1M raffinose, and then cooled to -196 degrees C in the presence of either 0.3M raffinose and 0.5M Me(2)SO (cryopreservation group 1) or 0.3M raffinose and 1.0M Me(2)SO (cryopreservation group 2). The control groups included untreated oocytes (untreated control) and oocytes microinjected with raffinose, but not frozen (injection control). The post-thaw survival rates were 83.9% and 80.6% for the cryopreservation group 1 and 2, respectively. The fertilization and blastocyst rates in the cryopreservation group 1 (90.0% and 77.8%, respectively) and 2 (94.6% and 72.5%, respectively) were also high and similar to the ones of the injection controls (97.8% and 78.5%, respectively) and untreated controls (98.8% and 83.6%, respectively). These results are consistent with the findings of our earlier studies and support the use of sugars as intra- and extracellular cryoprotectants. Furthermore, the results of the present study indicate that the presence of intra- and extracellular sugars alleviates high concentrations of conventional penetrating cryoprotectants, and thus minimizes their toxicity.

Cryopreservation of human hepatocytes for clinical use

Cryopreservation of hepatocytes is important for use both in research and for clinical application in hepatocyte transplantation. Cryopreservation causes damage to hepatocytes with the result that cell viability and function is reduced on thawing compared to fresh cells. There are many different protocols reported for freezing human hepatocytes mainly using DMSO as cryoprotectant. In this chapter the current detailed protocols used for cryopreservation and thawing of human hepatocytes for cell transplantation at the Cell Isolation Unit at King's College Hospital, London, are described. All procedures must be performed in a clean GMP environment using materials and reagents which are of pharmaceutical grade. The cryopreservation media is UW solution with added 300 mM glucose containing 10% DMSO and the thawing solution is EMEM containing 2% HSA. Freezing is performed in a controlled-rate freezer using a stepwise cooling programme.

The protective effect of selenoprotein P on injury in rat liver transplantation

BACKGROUND/AIMS

Selenoprotein P (SeP), a plasma protein, is considered to have a protective effect against various organ damages. We investigated whether addition of SeP to storage solution could attenuate cold ischemia/reperfusion injury (IRI) in rat liver transplantation.

METHODOLOGY

After 24 hrs cold preservation in either University of Wisconsin (UW) solution with or without SeP (1 micromol/L or 10 micromol/L), the liver was flushed with warm lactated Ringer's solution. Alanine aminotransferase (ALT) level in the venous effluent was measured. Orthotopic liver transplantation (OLTx) was then performed after the same preservation as above. Blood biochemical features and tissue lipid peroxide levels were measured after OLTx, and morphometric changes analyzed by hematoxylin and eosin, and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling (TUNEL) staining.

RESULTS

ALT levels in effluent in the SeP 10 group were significantly lower than those in other groups. Serum aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) were significantly decreased in the SeP 10 group. Histological examinations showed amelioration of sinusoidal damage in the SeP 10 group at 1 hr after OLTx. Percentages of necrotic areas and apoptotic sinusoidal endothelial cells were decreased in the SeP 10 group.

CONCLUSIONS

The addition of SeP to UW solution attenuates injury in OLTx.

Effect of oxygenated perfluorocarbon on isolated islets during transportation

BACKGROUND

Previous studies demonstrated the efficacy of the two-layer method (TLM) using oxygenated perfluorochemicals (PFC) for pancreas preservation. The current study investigated the effect of oxygenated PFC on isolated islets during transportation.

MATERIALS AND METHODS

Purified rat islets were stored in an airtight conical tube for 24h in RPMI culture medium at 22 degrees C or University of Wisconsin solution (UW) at 4 degrees C, either with or without oxygenated PFC. After storage, the islets were assessed for in vitro viability by static incubation (SI), FDA/PI staining, and energy status (ATP, energy charge, and ADP/ATP ratio) and for in vivo viability by a transplantation study.

RESULTS

UW at 4 degrees C and RPMI medium at 22 degrees C maintained islet quality almost equally in both in vitro and in vivo assessments. The ATP levels and energy status in the groups with PFC were significantly lower than those without PFC. The groups with PFC showed a significantly higher ADP/ATP ratio than those without PFC. In the transplantation study, blood glucose levels and AUC in the UW+PFC group were significantly higher than those in UW group.

CONCLUSIONS

UW at 4 degrees C and RPMI medium at 22 degrees C maintained islet quality equally under the conditions for islet transportation. The addition of oxygenated PFC, while advantageous for pancreas preservation, is not useful for islet transportation.

Changes and effect of PACAP-38 on intestinal ischemia-reperfusion and autotransplantation

Tissue injury caused by cold preservation and reperfusion during small bowel transplantation remains an unsolved problem. Increasing evidence suggests that pituitary adenylate cyclase-activating polypeptide (PACAP) has protective effects in several ischemia-reperfusion (I/R) models. This study investigated the effect of PACAP-38 on oxidative stress in autotransplanted intestine. We established sham-operated, I/R, and autotransplanted groups in Wistar rats (n = 55). We applied ischemia for 1 (GI), 2 (GII), or 3 hours (GIII). In autotransplanted groups, we performed total orthotopic intestinal autotransplantation. Grafts were preserved in University of Wisconsin (UW) solution for 1 (GIV), 2 (GV), 3 (GVI), or 6 (GVII) hours and in PACAP-38-containing UW for 1 (GVIII), 2 (GIX), 3 (GX), or 6 (GXI) hours. Reperfusion lasted 3 hours in each group. Endogenous PACAP-38 values were measured by radioimmunoassay. Oxidative stress parameters malondialdehyde (MDA), reduced glutathione (GSH), and superoxide dismutase (SOD) were measured in tissue homogenates. Concentration of endogenous PACAP-38 significantly decreased in GI to GIII compared with the sham-operated animals following I/R periods (P < .05). Cold preservation in UW and reperfusion of the intestine increased the level of tissue MDA in GIV to GVII, which correlated with the duration of cold storage. The content of GSH decreased in GIV to GVII to levels that were significantly different between GIV and GVIII and between GVII and GXI. SOD activity decreased dramatically in GIV to GVII with significantly higher activity in GIX to GXI. Our findings confirmed that I/R decreased endogenous PACAP-38 concentration. Administration of PACAP-38 to UW solution mitigated the oxidative injury during intestinal autotransplantation.