Quercetin inhibits caerulein-induced acute pancreatitis through regulating miR-216b by targeting MAP2K6 and NEAT1.

Acute pancreatitis (AP) is a common acute abdominal disease with high mortality and mortality rates. Increasing evidences clarified that Traditional Chinese Medicine (TCM) adjuvant therapy for AP can be used and it gives a positive effect. Quercetin (3,3',4',5,7-pentahydroxyflavone, QE) is a type of flavone compound with positive effect on cancer and inflammation prevention. The current study aims to identify the effect of QE on AP and potential molecular effect. In this case, caerulein (CAE) induced AP cell and mice model were used. QE alleviated inflammatory mediators TNF-α, IL-6, and IL-10 in experiments. In addition, miR-216b was increased based on QE treatment. In further study, MAP2K6 of p38/MAPK signaling pathway was identified as a direct target of miR-216b, and QE inhibited p38/MAPK signaling pathway through up-regulating miR-216b. Our study also first confirmed that long non-coding RNA NEAT1 is a direct target of miR-216b and can be suppressed by QE. Because of the target, NEAT1, miR-216b, and MAP2K6 formed a competitive endogenous RNA (ceRNA) network. Besides direct target mediated by QE, it also decreased TNF-α which down-regulated TRAF2 and MAP3K5 located on upstream of p38/MAPK signaling and formed a feedback loop. In conclusion, QE has a protective effect on AP through inhibiting p38/MAPK signaling pathway by up-regulating miR-216b and suppressing TNF-α.

Combined Omics Approaches Reveal the Roles of Non-canonical WNT7B Signaling and YY1 in the Proliferation of Human Pancreatic Progenitor Cells.

The proliferation of human pancreatic progenitor cells (PPCs) is critical for developing cell therapies for diabetes. Here, using transcriptome analysis combined with small interfering RNA (siRNA) screening, we revealed that WNT7B is a downstream growth factor of AT7867, a compound known to promote the proliferation of PPCs generated from human pluripotent stem cells. Feeder cell lines stably expressing mouse Wnt7a or Wnt7b, but not other Wnts, enhanced PPC proliferation in the absence of AT7867. Importantly, Wnt7a/b ligands did not activate the canonical Wnt pathway, and PPC proliferation depended on the non-canonical Wnt/PKC pathway. A comparison of the phosphoproteome in response to AT7867 or a newly synthesized AT7867 derivative uncovered the function of YY1 as a transcriptional regulator of WNT7B. Overall, our data highlight unknown roles of non-canonical WNT7B/PKC signaling and YY1 in human PPC proliferation and will contribute to the stable supply of a cell source for pancreatic disease modeling and therapeutic applications.

Intra-pancreatic tissue-derived mesenchymal stromal cells: a promising therapeutic potential with anti-inflammatory and pro-angiogenic profiles.

BACKGROUND: Human pancreata contain many types of cells, such as endocrine islets, acinar, ductal, fat, and mesenchymal stromal cells (MSCs). MSCs are important and shown to have a promising therapeutic potential to treat various disease conditions. METHODS: We investigated intra-pancreatic tissue-derived (IPTD) MSCs isolated from tissue fractions that are routinely discarded during pancreatic islet isolation of human cadaveric donors. Furthermore, whether pro-angiogenic and anti-inflammatory properties of these cells could be enhanced was investigated. RESULTS: IPTD-MSCs were expanded in GMP-compatible CMRL-1066 medium supplemented with 5% human platelet lysate (hPL). IPTD-MSCs were found to be highly pure, with > 95% positive for CD90, CD105, and CD73, and negative for CD45, CD34, CD14, and HLA-DR. Immunofluorescence staining of pancreas tissue demonstrated the presence of CD105+ cells in the vicinity of islets. IPTD-MSCs were capable of differentiation into adipocytes, chondrocytes, and osteoblasts in vitro, underscoring their multipotent features. When these cells were cultured in the presence of a low dose of TNF-α, gene expression of tumor necrosis factor alpha-stimulated gene-6 (TSG-6) was significantly increased, compared to control. In contrast, treating cells with dimethyloxallyl glycine (DMOG) (a prolyl 4-hydroxylase inhibitor) enhanced mRNA levels of nuclear factor erythroid 2-related factor 2 (NRF2) and vascular endothelial growth factor (VEGF). Interestingly, a combination of TNF-α and DMOG stimulated the optimal expression of all three genes in IPTD-MSCs. Conditioned medium of IPTD-MSCs treated with a combination of DMOG and TNF-α contained higher levels of pro-angiogenic (VEGF, IL-6, and IL-8) compared to controls, promoting angiogenesis of human endothelial cells in vitro. In contrast, levels of MCP-1, a pro-inflammatory cytokine, were reduced in the conditioned medium of IPTD-MSCs treated with a combination of DMOG and TNF-α. CONCLUSIONS: The results demonstrate that IPTD-MSCs reside within the pancreas and can be separated as part of a standard islet-isolation protocol. These IPTD-MSCs can be expanded and potentiated ex vivo to enhance their anti-inflammatory and pro-angiogenic profiles. The fact that IPTD-MSCs are generated in a GMP-compatible procedure implicates a direct clinical application.

Glucose stimulates somatostatin secretion in pancreatic δ-cells by cAMP-dependent intracellular Ca2+ release.

Somatostatin secretion from pancreatic islet δ-cells is stimulated by elevated glucose levels, but the underlying mechanisms have only partially been elucidated. Here we show that glucose-induced somatostatin secretion (GISS) involves both membrane potential-dependent and -independent pathways. Although glucose-induced electrical activity triggers somatostatin release, the sugar also stimulates GISS via a cAMP-dependent stimulation of CICR and exocytosis of somatostatin. The latter effect is more quantitatively important and in mouse islets depolarized by 70 mM extracellular K+ , increasing glucose from 1 mM to 20 mM produced an ∼3.5-fold stimulation of somatostatin secretion, an effect that was mimicked by the application of the adenylyl cyclase activator forskolin. Inhibiting cAMP-dependent pathways with PKI or ESI-05, which inhibit PKA and exchange protein directly activated by cAMP 2 (Epac2), respectively, reduced glucose/forskolin-induced somatostatin secretion. Ryanodine produced a similar effect that was not additive to that of the PKA or Epac2 inhibitors. Intracellular application of cAMP produced a concentration-dependent stimulation of somatostatin exocytosis and elevation of cytoplasmic Ca2+ ([Ca2+]i). Both effects were inhibited by ESI-05 and thapsigargin (an inhibitor of SERCA). By contrast, inhibition of PKA suppressed δ-cell exocytosis without affecting [Ca2+]i Simultaneous recordings of electrical activity and [Ca2+]i in δ-cells expressing the genetically encoded Ca2+ indicator GCaMP3 revealed that the majority of glucose-induced [Ca2+]i spikes did not correlate with δ-cell electrical activity but instead reflected Ca2+ release from the ER. These spontaneous [Ca2+]i spikes are resistant to PKI but sensitive to ESI-05 or thapsigargin. We propose that cAMP links an increase in plasma glucose to stimulation of somatostatin secretion by promoting CICR, thus evoking exocytosis of somatostatin-containing secretory vesicles in the δ-cell.

Mitochondrial Targeting of Antioxidants Alters Pancreatic Acinar Cell Bioenergetics and Determines Cell Fate.

Mitochondrial dysfunction is a core feature of acute pancreatitis, a severe disease in which oxidative stress is elevated. Mitochondrial targeting of antioxidants is a potential therapeutic strategy for this and other diseases, although thus far mixed results have been reported. We investigated the effects of mitochondrial targeting with the antioxidant MitoQ on pancreatic acinar cell bioenergetics, adenosine triphosphate (ATP) production and cell fate, in comparison with the non-antioxidant control decyltriphenylphosphonium bromide (DecylTPP) and general antioxidant N-acetylcysteine (NAC). MitoQ (µM range) and NAC (mM range) caused sustained elevations of basal respiration and the inhibition of spare respiratory capacity, which was attributable to an antioxidant action since these effects were minimal with DecylTPP. Although MitoQ but not DecylTPP decreased cellular NADH levels, mitochondrial ATP turnover capacity and cellular ATP concentrations were markedly reduced by both MitoQ and DecylTPP, indicating a non-specific effect of mitochondrial targeting. All three compounds were associated with a compensatory elevation of glycolysis and concentration-dependent increases in acinar cell apoptosis and necrosis. These data suggest that reactive oxygen species (ROS) contribute a significant negative feedback control of basal cellular metabolism. Mitochondrial targeting using positively charged molecules that insert into the inner mitochondrial member appears to be deleterious in pancreatic acinar cells, as does an antioxidant strategy for the treatment of acute pancreatitis.

Determination of cellular vitamin C dynamics by HPLC-DAD.

A redox-sensitive inter-conversion between ascorbic acid (ASC) and its oxidized form dehydroascorbic acid (DHA) in the intracellular environment has been of exceptional interest to recent metabolomics and pharmaceutical research. We developed a chromatographic protocol to instantly determine these vitamers with each identity from cellular extracts, without any labeling and pretreatments. Owing to its simplicity, one can readily continue the assay for hours, an otherwise difficult to cover timescale at which the intracellular DHA-ASC conversion comes into play. The method was validated for the analysis of pancreatic cancer cells, to our knowledge the first-ever study on a nucleated cell type, to trace in detail their kinetics of glucose transporter-dependent DHA uptake and, simultaneously, that for the intracellular ASC conversion. The simplest of all the relevant techniques and yet with the unique ability to provide each vitamer identity on a high-throughput basis, this method should offer the most practical option for VC-involved physiological and pharmaceutical studies including high-dose VC cancer therapy.

Small molecules and extrinsic factors promoting differentiation of stem cells into insulin-producing cells.

In the modern world, type-2 diabetes mellitus has become a leading public healthcare problem, due to major risks of morbidity and mortality. Prevalence has increased significantly in recent decades. Treatment involves oral hypoglycemic agents or insulin replacement therapy. Development is ongoing for cell-based diabetes therapies using stem cells with the potential to differentiate into insulin-producing cells (IPCs): embryonic stem cells (ESCs), mesenchymal stem cells (MSCs), induced pluripotent stem cells (iPSCs), and stem cells from adult pancreas, liver, central nervous system, bone marrow and adipose tissue. Successful induction of iPSCs, however, depends on the quantity and quality of available stem cells and the development of adapted protocols determining the environment of extrinsic factors and involvement of small molecules. Validating such new cell therapies must be founded on this experimental rationale.

Activating Effects of Phenolics from Apache Red Zea mays L. on Free Fatty Acid Receptor 1 and Glucokinase Evaluated with a Dual Culture System with Epithelial, Pancreatic, and Liver Cells.

The aim was to characterize a phenolic-rich water extract from the pericarp of an improved genotype of Apache red maize (RPE) and evaluate its ability to activate the type 2 diabetes markers free fatty acid receptor 1 (GPR40) and glucokinase (GK) in vitro. The extract contained mainly phenolic acids, anthocyanins, and other flavonoids. RPE inhibited α-amylase (IC50 = 88.3 µg/mL), α-glucosidase (IC50 = 169.3 µg/mL), and reduced glucose transport in a Caco-2 cell monolayer (up to 25%). Furthermore, RPE activated GPR40 (EC50 = 77.7 µg/mL) in pancreatic INS-1E cells and GK (EC50 = 43.4 µg/mL) in liver HepG2 cells, potentially through allosteric modulation. RPE activated GPR40-related insulin secretory pathway and activated the glucose metabolism regulator AMPK (up to 78%). Our results support the hypothesis that foods with a high concentration of anthocyanins and phenolic acids, such as in the selected variety of maize used, could ameliorate obesity and type 2 diabetes comorbidities.

Calcium: A Crucial Potentiator for Efficient Enzyme Digestion of the Human Pancreas.

BACKGROUND: Effective digestive enzymes are crucial for successful islet isolation. Supplemental proteases are essential because they synergize with collagenase for effective pancreatic digestion. The activity of these enzymes is critically dependent on the presence of Ca2+ ions at a concentration of 5-10 mM. The present study aimed to determine the Ca2+ concentration during human islet isolation and to ascertain whether the addition of supplementary Ca2+ is required to maintain an optimal Ca2+ concentration during the various phases of the islet isolation process. METHODS: Human islets were isolated according to standard methods and isolation parameters. Islet quality control and the number of isolations fulfilling standard transplantation criteria were evaluated. Ca2+ was determined by using standard clinical chemistry routines. Islet isolation was performed with or without addition of supplementary Ca2+ to reach a Ca2+ of 5 mM. RESULTS: Ca2+ concentration was markedly reduced in bicarbonate-based buffers, especially if additional bicarbonate was used to adjust the pH as recommended by the Clinical Islet Transplantation Consortium. A major reduction in Ca2+ concentration was also observed during pancreatic enzyme perfusion, digestion, and harvest. Additional Ca2+ supplementation of media used for dissolving the enzymes and during digestion, perfusion, and harvest was necessary in order to obtain the concentration recommended for optimal enzyme activity and efficient liberation of a large number of islets from the human pancreas. CONCLUSIONS: Ca2+ is to a large extent consumed during clinical islet isolation, and in the absence of supplementation, the concentration fell below that recommended for optimal enzyme activity. Ca2+ supplementation of the media used during human pancreas digestion is necessary to maintain the concentration recommended for optimal enzyme activity. Addition of Ca2+ to the enzyme blend has been implemented in the standard isolation protocols in the Nordic Network for Clinical Islet Transplantation.

α-Ketoglutarate Promotes Pancreatic Progenitor-Like Cell Proliferation.

A major source of ß cell generation is pancreatic progenitor-like cell differentiation. Multiple studies have confirmed that stem cell metabolism plays important roles in self-renewal and proliferation. In the absence of glucose, glutamine provides the energy for cell division and growth. Furthermore, α-ketoglutarate (αKG), a precursor for glutamine synthesis, is sufficient for enabling glutamine-independent cell proliferation. We have demonstrated that αKG contributes to the large-scale proliferation of pancreatic progenitor-like cells that can provide an ample amount of clinically relevant ß cells. We compared the mRNA expression of a subset of genes, the abundance of ATP, reactive oxide species, mitochondrial number, and the colony-forming frequency between mouse pancreatic CD133⁺ and CD133- cells. We employed Real-Time PCR, immunostaining and passage assays to investigate self-renewal and proliferation of pancreatic progenitor-like cells in a 3D culture system in the presence and absence of αKG. The energy metabolism of CD133⁺ cells was more prone to oxidative phosphorylation. However, in the 3D culture system, when αKG was supplemented to the culture medium, the proliferation of the pancreatic progenitor-like cells was significantly elevated. We confirmed that the presence of αKG correlated with the up-regulation of Ten-Eleven Translocation (Tet). αKG can promote the proliferation of pancreatic progenitor-like cells via the up-regulation of Tet.

Orai1-Mediated Antimicrobial Secretion from Pancreatic Acini Shapes the Gut Microbiome and Regulates Gut Innate Immunity.

The gut microbiome participates in numerous physiologic functions and communicates intimately with the host immune system. Antimicrobial peptides are critical components of intestinal innate immunity. We report a prominent role for antimicrobials secreted by pancreatic acini in shaping the gut microbiome that is essential for intestinal innate immunity, barrier function, and survival. Deletion of the Ca2+ channel Orai1 in pancreatic acini of adult mice resulted in 60%-70% mortality within 3 weeks. Despite robust activation of the intestinal innate immune response, mice lacking acinar Orai1 exhibited intestinal bacterial outgrowth and dysbiosis, ultimately causing systemic translocation, inflammation, and death. While digestive enzyme supplementation was ineffective, treatments constraining bacterial outgrowth (purified liquid diet, broad-spectrum antibiotics) rescued survival, feeding, and weight gain. Pancreatic levels of cathelicidin-related antimicrobial peptide (CRAMP) were reduced, and supplement of synthetic CRAMP prevented intestinal disease. These findings reveal a critical role for antimicrobial pancreatic secretion in gut innate immunity.

MALDI versus ESI: The Impact of the Ion Source on Peptide Identification.

For mass spectrometry-based proteomic analyses, electrospray ionization (ESI) and matrix-assisted laser desorption/ionization (MALDI) are the commonly used ionization techniques. To investigate the influence of the ion source on peptide detection in large-scale proteomics, an optimized GeLC/MS workflow was developed and applied either with ESI/MS or with MALDI/MS for the proteomic analysis of different human cell lines of pancreatic origin. Statistical analysis of the resulting data set with more than 72 000 peptides emphasized the complementary character of the two methods, as the percentage of peptides identified with both approaches was as low as 39%. Significant differences between the resulting peptide sets were observed with respect to amino acid composition, charge-related parameters, hydrophobicity, and modifications of the detected peptides and could be linked to factors governing the respective ion yields in ESI and MALDI.

Impact of an Energy Drink on the Structure of Stomach and Pancreas of Albino Rat: Can Omega-3 Provide a Protection?

BACKGROUND AND OBJECTIVES: A controversy developed between the benefits of energy drinks (EDs) versus the possible health threats since its revolution. Lack of information was a call to assess the effect of chronic consumption of Power Horse (PH) as one of the EDs, on the structure of pancreas and fundic mucosa of stomach in rats, and possible protective role of Omega-3. MATERIALS AND METHODS: Thirty two adult male albino rats were divided equally into 4 groups; control received group which only received a standard diet, Omega-3 group, PH group which given PH and PH plus Omega-3 group received both PH plus Omega-3 for 4 weeks. Biochemical assessment of blood glucose, serum insulin, gastrin, tumor necrosis factor alpha (TNF-α) and inducible nitric oxide synthetase (iNOS) was performed. The antioxidant activity and histopathological examination of both pancreatic tissue and fundic mucosa of stomach were assessed. RESULTS: Administration of PH significantly increased serum insulin and glucose levels while it significantly reduced serum gastrin level compared to control. PH also caused oxidants/antioxidants imbalance in both pancreas and fundic mucosa. The latter revealed degenerative changes and increased apoptosis which was evident by increased caspase-3 immunoexpression. Pancreas exhibited signs of ß-cells overstimulation. Fundic mucosa showed reduced number of parietal cells, gastrin hormone expression compared to control group. Omega-3 administration could alleviate, to some extent, these changes. It significantly decreased TNF-α, iNOS and reduced glutathione (GSH) as well as significantly increasing superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities compared to the group which received PH alone. CONCLUSION: Power Horse intake significantly injures islet cells, pancreatic acini as well as the glandular cells of the fundic mucosa. Omega-3 decreases these detrimental effects mostly through its antioxidant and anti-inflammatory action.

Intervenção nas situações de crise psíquica: dificuldades e sugestões de uma equipe de atenção pré-hospitalar / Intervention in situations of psychic crisis: challenges and suggestions of a prehospital care staff / Intervención en situaciones de crisis psíquica: problemas y sugerencias de un equipo de atención prehospitalaria

Pesquisa descritiva, qualitativa, que objetivou conhecer como os profissionais de atenção pré-hospitalar percebem as intervenções nas pessoas em crise psíquica. O estudo foi realizado, no estado de Santa Catarina, com quatro equipes das Unidades de Suporte Básico do Serviço de Atendimento Móvel de Urgência, mediante entrevista, no período de abril a junho de 2011. Utilizou-se como método de análise o Discurso do Sujeito Coletivo. Dos resultados emergiram dois temas: Percepção das dificuldades no atendimento à pessoa em crise psíquica e Sugestões na busca por um atendimento mais próximo do desejado à pessoa em crise psíquica. As dificuldades apontadas se relacionam à falta de capacitação e de um local para encaminhamento e sugerem treinamento e sistematização do atendimento. Conclui-se que se faz necessário investir em processo de formação pautado em novas estratégias de cuidado norteadas pelos princípios do SUS e no paradigma psicossocial, além de rediscutir a estratégia de protocolos como sistemas norteadores e não padronizadores.

A qualitative and descriptive research, aimed at knowing how the pre-hospital care professionals perceive the interventions towards people in mental crisis. The study was developed in Santa Catarina with four teams of basic life support units of the Department of Mobile Emergency Care, during April to June 2011. The Collective Subject Discourse was used as the method of analysis. Two themes emerged: Awareness of the difficulties in meeting a person in mental crisis and Suggestions in the search for a closer attention to the person in mental crisis. The difficulties mentioned were related to the lack of training and a local to forward the patients, suggesting a better training and systematization of care. We conclude that it is necessary to invest in the educational process, based on new care strategies guided by the principles of SUS and of the psychosocial paradigm, and revisit the strategy of protocols as guidelines and not as standardizing systems.

Investigación descriptivo-cualitativa, que objetivó conocer como los profesionales de la atención pre-hospitalaria perciben las intervenciones en personas con crisis mental. El estudió fue realizado en Santa Catarina con cuatro equipos de las Unidades de Soporte Vital Básico, mediante entrevista realizada de abril a junio de 2011. El Discurso del Sujeto Colectivo fue utilizado como método de análisis; surgiendo dos temas: Percepción de las dificultades en la atención a la persona en crisis mental y Sugerencias en la búsqueda de una mejor atención a la persona en crisis mental. Las dificultades mencionadas se relacionan con la falta de capacitación y lugar para la atención, sugiriendo un mejor entrenamiento y sistematización de la atención. Se resalta la necesidad de invertir en el proceso de formación basado en nuevas estrategias de atención guiadas por los principios del SUS y el paradigma psicosocial, y revisar la estrategia de protocolos como nortes no estandarizados.

[Effect of Mudan Granule on islets beta cell function in monosodium glutamate induced obese mice with insulin resistance: an experimental study].

OBJECTIVE: To study the effect of Mudan Granule (MD) on the glucose metabolism and beta cell function in monosodium glutamate (MSG) induced obese mice with insulin resistance (IR). METHODS: MSG obese mice were induced by subcutaneous injecting MSG (4 g/kg for 7 successive days in neonatal ICR mice). Forty MSG mice with IR features were recruited and divided into four groups according to body weight, fasting blood glucose, triglyceride (TG), total cholesterol (TC), and the percentage of blood glucose decreased within 40 min in the IR test, i.e., the model group (Con), the low dose MD group, the high dose MD group, and the Metformin group (Met). Besides, another 10 ICR mice were recruited as the normal control group (Nor). The water solvent of 2.5 g/kg MD or 5 g/kg MD was respectively administered to mice in the low dose MD group and the high dose MD group. Metformin hydrochloride was given to mice in the Met group at 0.2 g/kg body weight. Equal dose solvent distilled water was administered to mice in the Nor group and the Con group by gastrogavage, once per day. All medication was lasted for 15 weeks. Insulin tolerance test (ITT) and oral glucose tolerance test (OGTT) were performed after 6 weeks of treatment. Beta cell function was assessed by hyperglycemic clamp technique. The morphological changes in the pancreas were evaluated by hematoxylin-eosin (HE) staining. Changes of iNOS, NF-kappaB p65, and p-NF-kappaB p65 in the pancreas were tested. RESULTS: Compared with the Nor group, the blood glucose level, AUC, and fasting blood insulin, ONOO-contents, iNOS activities, and the expression of iNOS, NF-kappaB p65 subunit, pNF-kappaB p65 subunit obviously increased; decreased percentage of blood glucose within 40 min in ITT, glucose infusion rate (GIR), Clamp 1 min insulin, and Max-Insulin obviously decreased in the Con group (P < 0.05, P < 0.01). Compared with the Con group, the aforesaid indices could be improved in the Met group (P < 0.05, P < 0.01). In the low dose MD group, AUC, iNOS activities, and the expression of iNOS and p-NF-kappaB p65 subunit obviously decreased; percentage of blood glucose within 40 min in ITT and GIR obviously increased (P < 0.05, P < 0.01). In the high dose MD group, AUC, ONOO-contents, iNOS activities, and the expression of iNOS, NF-kappaB p65 subunit, and p-NF-KB p65 subunit obviously decreased; percentage of blood glucose within 40 min in ITT, Max-Insulin, and GIR obviously increased (P < 0.05, P < 0.01). CONCLUSION: MD could significantly improve IR and functional disorder of 3 cells in MSG obese mice, which might be associated with lowering inflammatory reaction in the pancreas.

Pretreatment of donor pigs with a diet rich in soybean oil increases the yield of isolated islets.

INTRODUCTION: The pig is considered the donor species of choice for islet xenotransplantation. However, isolation of porcine islets is difficult, particularly from young pigs. Early life exposure to a high-fat diet (HFD) reportedly encourages islet ß-cell expansion in neonatal rodents and improves islet viability in culture from pretreated weanling pigs. In this study, we examined the influence of young donor pretreatment with a soybean oil-enriched HFD on porcine islet mass and yield after islet isolation. MATERIALS AND METHODS: Postweaning and between days 70 and 250, pigs were fed either a standard diet (control group; n = 5) or an HFD (experimental group; n = 6). Biochemical blood parameters and acute C-peptide response to intravenous glucose were monitored before pancreas procurement. The study was blinded to objectively evaluate the influence of treated diet. After procurement, pancreas biopsy samples were taken from control and pretreated donor pigs to assess islet number by using a dithizone scoring method and histologic islet area fraction determination. Control and HFD donor pig islets were isolated by using our standard isolation protocol to determine islet yield. Islet isolation characteristics and islet quality were assessed in both groups, and the results were compared. RESULTS: There were no significant differences in the donor characteristics (age, body weight, glucose disposal rate, acute C-peptide response to intravenous glucose, cholesterol, and aspartate aminotransferase) except fasting blood glucose level between the control and treatment groups (84 ± 6 vs 99 ± 12 mg/dL; P = .0317). The stimulated insulin and C-peptide levels between groups were similar. However, the dithizone score was slightly higher in the treatment group compared with the control group (95.4 ± 38.5 vs 62.6 ± 23.9; P = .1208). Digestion time, digested pancreas weight, pellet volume, and the fragility index were similar in both groups. However, the average islet count (islet equivalent number/g pancreas) at the digest level was significantly higher in the HFD group than in the control group (1578 ± 994 vs 738 ± 202; P = .0344). The functional viability of 2- and 7 day-cultured islets, as assessed by using oxygen consumption rate corrected for DNA, was similar in both groups. CONCLUSIONS: Pretreatment of pigs with HFD enriched with soybean oil could potentially be used to improve the islet mass in donor pigs. Further studies are needed to confirm and optimize the use of HFD for the purpose of increasing islet yield from young donor pigs.

Treatment with Cordyceps sinensis enriches Treg population in peripheral lymph nodes and delays type I diabetes development in NOD mice.

Cordyceps sinensis is a widely used Chinese traditional herb with a long history. In China C. sinensis is usually applied in the treatment of respiratory diseases, however, the efficacy of C. sinensis still lacks experimental evidence. Type I diabetes is a multi-factor related autoimmune disease caused by cellular-mediated destruction of insulin-producing pancreatic beta cells in the islets in human. We tested C. sinensis for its ability to work as an immune modulator in NOD mice, an animal model which mimicks the progression of type I diabetes in humans and found that treatment with C. sinensis extract could slow down disease development in NOD mice. Further research also suggested that treatment with C. sinensis extract increased the frequency of Treg cells and IFN-gama producing Th1 cells in peripheral lymph nodes. However, C. sinensis has no effect on the natural Treg cell differentiation in thymus.

Development of pancreas storage solutions: Initial screening of cytoprotective supplements for ß-cell survival and metabolic status after hypothermic storage.

Insulin-dependent diabetes mellitus is one of the leading causes of death world-wide. Donor-derived pancreas and Islet of Langerhans transplantation are potential cures; however, postmortem ischemia impacts islet quality. The murine ßt3 cell line was employed as a model to study cell viability and proliferation after hypothermic storage by comparing Belzer's Machine Perfusion Solution with Unisol™ Solution. The objective was to determine which of these solutions provided the best base line support for ßt3 cells and to screen potential cytoprotective additives to the solutions. Initial ßt3 cell viability was similar in the two storage solutions; however, better proliferation was observed after storage in Unisol Solution. The caspase inhibitor, Q-VD-OPH, and α-tocopherol improved viability in both storage solutions, suggesting that apoptotic pathways may be responsible for cell death during hypothermic storage of ßt3 cells. Analysis of apoptosis markers, caspase activity, and DNA laddering showed a reduction in apoptosis when these additives were included. The effects of Q-VD-OPH and α-tocopherol were also synergistic when employed together during either hypothermic exposure, post-hypothermic physiologic incubation, or combinations of hypothermic exposure and physiologic incubation. These results suggest that both supplements should be included in pancreas hypothermic storage solutions and in islet culture media during post-isolation culture prior to transplantation.

Role of substrates in diabetes therapy: stem cell differentiation and islet transplantation.

Type 1 diabetes affects more than a million people in the United States and many more across the world. While pharmaceutical interventions and insulin supplementation are the most commonplace treatment of diabetes, these are not essentially cures and can potentially lead to long-term complications. Transplantation of insulin-producing Islets of Langerhans from donor pancreas has been established as a promising alternative to diabetes therapy. While successful islet transplantation has the potential of providing a cure, the primary hurdles to be overcome for it to be clinically viable are the scarcity of donor islets and immune rejection of transplanted islets. Recent advances in stem cell culture and differentiation techniques have established stem cells as a likely source of transplantable islets. Different stem cell sources have been induced toward pancreatic differentiation using specific chemical perturbations along with use of specific substrates. An approach to overcoming the second hurdle of immune rejection of transplantable islets is to encapsulate the islets in specific biomaterials. In this review, we discuss the extensive use of various substrates for pancreatic differentiation of different stem cell sources, along with different biomaterial designs used for islet transplantation.