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Objective:The purpose of this study was to explore the therapeutic effect of modified Xiaoke prescription on patients with Yin deficiency and heat excessive type 2 diabetes mellitus (T2DM), and its influence on TCM syndrome scores, pancreatic islet function and oxidative stress.Methods:Randomized controlled trial. Eighty patients with Yin deficiency and heat excessive T2DM treated in the hospital between January and July 2021 were selected, and divided into observation group (41 cases) and control group (39 cases) by random number table method. Patients in the control group were treated with conventional western medicine, and patients in the observation group were treated with modified Xiaoke Prescription on the basis of the control group. Both groups were treated for 1 month. TCM syndrome scores were performed before and after treatment. Fasting plasma glucose (FPG) and 2 hPG were measured by glucose oxidase method. Serum HbA1c, malondialdehyde (MDA), 8-hydroxy-2'-deoxyguanosine (8-OHdG) levels and SOD activity were measured by ELISA. The levels of low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C) and total cholesterol (TC) were detected by colorimetry.Results:The total effective rate of the observation group was 92.68% (38/41), and that of the control group was 76.92% (30/39). The difference between the two groups was statistically significant ( χ2=3.89, P=0.048). After treatment, the scores of tiredness and fatigue, thirst and appetite, overeating and hunger, redness of tongue and lack of saliva and total scores in the observation group were significantly lower than those in the control group ( t=4.46, 16.89, 13.37, 8.58, 8.38, P<0.01). After treatment, the levels of serum FPG [(7.31±0.90) mmol/L vs. (8.72±1.50) mmol/L, t=5.13], 2 hPG [(9.64±2.05) mmol/L vs. (12.85±1.20) mmol/L, t=8.49], HbA1c [(7.64±0.58)% vs. (8.11±1.35)%, t=2.04] in the observation group were significantly lower than those in the control group ( P<0.05); MDA [(3.96±1.00) mmol/L vs. (5.04±0.73) mmol/L, t=5.49], 8-OHdG [(203.41±30.70) ng/L vs. (234.50±59.00) ng/L, t=2.98] levels were significantly lower than those in the control group ( P<0.05); The activity of serum SOD [(48.64±5.05) mU/L vs. (41.75±3.58) mU/L, t=7.01] was significantly higher than that of the control group ( P<0.01); The serum LDL-C [(2.01±0.11) mmol/L vs. (2.56±0.25) mmol/L, t=12.84], TC [(4.75±0.20) mmol/L vs. (5.12±0.07) mmol/L, t=10.93] levels were significantly lower than those in the control group ( P<0.01); The serum HDL-C [(1.62±0.18) mmol/L vs. (1.24±0.42) mmol/L, t=5.31] level was significantly higher than that of the control group ( P<0.01). Conclusion:The modified Xiaoke Prescription can improve clinical symptoms, curative effect and pancreatic function, and relieve oxidative stress on the patients with T2DM.
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ObjectiveTo investigate the effect of Zuoguiwan on pancreatic islet function in offspring of gestational diabetes mellitus （GDM） maternal rat model and explore the mechanisms of Zuoguiwan in improving pancreatic islet function based on postpartum pancreatic regeneration. MethodHealthy female SD rats with normal blood glucose levels were paired with male rats in a 2∶1 ratio and housed together. Pregnancy was confirmed based on vaginal plugs or vaginal smears. The pregnant rats were divided into the following groups： normal group， model group， insulin group （insulin Detemir， 20 U·kg-1）， low-dose Zuoguiwan group （1.89 g·kg-1）， and high-dose Zuoguiwan group （3.78 g·kg-1）. The GDM rat model was induced using streptozotocin in rats except for those in the normal group. The model was confirmed by blood glucose testing in the maternal rats. Except for the normal and model groups， the other groups received daily administration of corresponding treatments. At 21 days after birth， fasting blood glucose （FBG） and fasting serum insulin （FINS） levels were measured in 6 offspring from each group. The homeostasis model assessment of insulin resistance （HOMA-IR） was calculated， and an oral glucose tolerance test （OGTT） was performed on additional 12 offspring from each group. Blood samples were taken from the abdominal aorta of the offspring at postnatal day 22， and enzyme-linked immunosorbent assay （ELISA） was used to measure insulin， glucagon （GC）， pancreatic polypeptide （PPY）， and somatostatin （SS） levels in the serum. Hematoxylin-eosin （HE） staining was performed to observe pathological changes in the pancreatic tissue of the offspring. Immunofluorescence （IF） was used to observe the area and structure of the pancreatic islets. Western blot was used to detect the expression of key proteins involved in the development and functional expression of pancreatic β-cells， namely pancreatic and duodenal homeobox factor 1 （Pdx1）， Nkx6.1， and Glucose transporter 2 （Glut2）. ResultCompared with the normal group， the model group showed significant increases in FBG and FINS levels， and HOMA-IR （P<0.01）. Compared with the model group， the insulin group showed significant decreases in FBG levels and HOMA-IR （P<0.01）， the low-dose Zuoguiwan group showed a significant decrease in FBG levels （P<0.05）， and the high-dose Zuoguiwan group showed significant decreases in FBG and FINS levels， and HOMA-IR （P<0.01）. Compared with the normal group， the model group showed significant increases in OGTT 60-min blood glucose levels and AUC index （P<0.05， P<0.01）. Compared with the model group， the high-dose Zuoguiwan group showed significant decreases in OGTT60-min blood glucose levels and area under the curve（AUC） index （P<0.05， P<0.01）. HE staining of pancreatic tissue showed that compared with the normal group， the model group had a reduced number of islets and a loose arrangement of acinar cells. Compared with the model group， the groups with drug treatment showed increased number of islets and a compact arrangement of acinar cells. Compared with the normal group， the model group had significantly increased levels of insulin， GC， PPY， and SS in the serum （P<0.01）. Compared with the model group， the low-dose and high-dose Zuoguiwan groups and the insulin group showed significantly decreased serum levels of insulin， GC， PPY， and SS （P<0.05， P<0.01）. IF results showed that compared with the normal group， the model group had a significantly lower positive rate of insulin （P<0.05）. Compared with the model group， the low-dose and high-dose Zuoguiwan groups showed a significant increase in the positive rate of insulin （P<0.05）. There was no significant difference in the positive rate of GC among the groups. In terms of the proportion of insulin and GC in individual islets， compared with the normal group， the model group showed a significant decrease in the proportion of insulin （P<0.01） and a significant increase in the proportion of GC （P<0.01）. Compared with the model group， the low-dose and high-dose Zuoguiwan groups showed significantly increased proportion of insulin （P<0.01） and significantly decreased proportion of GC （P<0.01）. Compared with the normal group， the model group showed significantly decreased expression levels of Pdx1， Nkx6.1， and Glut2 proteins in the pancreatic tissue of GDM offspring （P<0.05）. Compared with the model group， the insulin group and the low-dose Zuoguiwan group showed significant increases in the expression levels of Pdx1 and Nkx6.1 proteins in the pancreatic tissue of GDM offspring （P<0.05）， and the low-dose and high-dose Zuoguiwan groups showed significant increases in the expression levels of Glut2 protein （P<0.05）. ConclusionZuoguiwan can promote pancreatic islet development in offspring of GDM maternal rat model， improve pancreatic islet morphology and function， and alleviate insulin resistance. Its mechanism of action may be related to the regulation of Pdx1， Nkx6.1， and Glut2 protein expression in the pancreatic tissue of offspring.
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Type 2 diabetes mellitus (T2DM) therapy is facing the challenges of long-term medication and gradual destruction of pancreatic islet β-cells. Therefore, it is timely to develop oral prolonged action formulations to improve compliance, while restoring β-cells survival and function. Herein, we designed a simple nanoparticle with enhanced oral absorption and pancreas accumulation property, which combined apical sodium-dependent bile acid transporter-mediated intestinal uptake and lymphatic transportation. In this system, taurocholic acid (TCA) modified poly(lactic-co-glycolic acid) (PLGA) was employed to achieve pancreas location, hydroxychloroquine (HCQ) was loaded to execute therapeutic efficacy, and 1,2-dilauroyl-sn-glycero-3-phosphocholine (DLPC) was introduced as stabilizer together with synergist (PLGA-TCA/DLPC/HCQ). In vitro and in vivo results have proven that PLGA-TCA/DLPC/HCQ reversed the pancreatic islets damage and dysfunction, thus impeding hyperglycemia progression and restoring systemic glucose homeostasis via only once administration every day. In terms of mechanism PLGA-TCA/DLPC/HCQ ameliorated oxidative stress, remodeled the inflammatory pancreas microenvironment, and activated PI3K/AKT signaling pathway without obvious toxicity. This strategy not only provides an oral delivery platform for increasing absorption and pancreas targetability but also opens a new avenue for thorough T2DM treatment.
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Objective To investigate the effect of compound Fufangteng mixture-containing serum on the proliferation of bone marrow mesenchymal stem cell (BMSC) and its mechanism. Methods Rat BMSC were isolated, cultured and purified in vitro by direct adherence method. Cell morphology was observed. Surface markers were identified by flow cytometry. The rats were treated with compound Fufangteng mixture at a dose of 3 mL/(kg·d) by gavage for 14 d, and then the drug-containing serum was collected. BMSC were divided into the blank control group, drug-containing serum group, Notch1 small interfering ribonucleic acid (siRNA) group and Notch1 siRNA+drug-containing serum group. The proliferation rate of BMSC was detected and the relative expression levels of Notch1 signaling pathway-associated messenger ribonucleic acid (mRNA) and proteins were measured in each group. Results Microscopic observation showed that the first generation BMSC were seen in the long spindle shape, and grown in the parallel or spiral pattern. The third generation BMSC positively expressed CD90 and CD44, whereas were negative for CD45. Compared with the blank control group, the proliferation rate of BMSC in the drug-containing serum group and Notch1 siRNA+ drug-containing serum group was significantly increased, whereas that of BMSC was significantly decreased in the Notch1 siRNA group (all P < 0.05). Compared with the Notch1 siRNA group, the proliferation rate of BMSC was significantly increased in the Notch1 siRNA+drug-containing serum group (P < 0.05). Compared with the blank control group, the relative expression levels of Hey1 and Delta-like ligand (DLL)1 mRNA and proteins were significantly up-regulated in the drug-containing serum group, whereas those were significantly down-regulated in the Notch1 siRNA group and Notch1 siRNA+drug-containing serum group (all P < 0.05). Compared with the Notch1 siRNA group, the relative expression levels of Hey1 and DLL1 mRNA and proteins were significantly up-regulated in the Notch1 siRNA+drug-containing serum group (all P < 0.05). Conclusions Compound Fufangteng mixture-containing serum may promote the proliferation of rat BMSC, and its mechanism is probably associated with the activation of Notch1 signaling pathway.
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Objective This study aimed to assess the protective value of adiponectin (APN) in pancreatic islet injury induced by chronic intermittent hypoxia (CIH). Methods Sixty rats were randomly divided into three groups: normal control (NC) group, CIH group, and CIH with APN supplement (CIH+APN) group. After 5 weeks of CIH exposure, we conducted oral glucose tolerance tests (OGTT) and insulin released test (IRT), examined and compared the adenosine triphosphate (ATP) levels, mitochondrial membrane potential (MMP) levels, reactive oxygen species (ROS) levels, enzymes gene expression levels of
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Animals , Rats , Adiponectin/genetics , Hypoxia , Islets of Langerhans , Mitochondrial Dynamics , Rats, WistarABSTRACT
Obesity and its comorbidities are becoming epidemic in the Western world. Beta cell mass estimation is an important indicator to track the progression of insulin resistance/type 2 diabetes, particularly in experimental studies, where it can be performed with stereological tools in an unbiased way. In this work, we present a simple protocol that can contribute to doing the practice of estimating the mass of beta cells more frequent and reproducible. As with any quantitative study, the necessary precautions regarding sampling and randomness must be respected.
La obesidad y sus comorbilidades se están convirtiendo en una epidemia en el mundo occidental. La estimación de la masa de células beta es un indicador importante para rastrear la progresión de la resistencia a la insulina/diabetes tipo 2, particularmente en estudios experimentales, donde se puede realizar con herramientas estereológicas de manera imparcial. En este trabajo presentamos un protocolo simple que puede contribuir a que la práctica de estimar la masa de células beta sea más frecuente y reproducible. Como en cualquier estudio cuantitativo, deben respetarse las precauciones necesarias con respecto al muestreo y la aleatoriedad.
Subject(s)
Humans , Cytological Techniques/methods , Islets of Langerhans/cytology , Insulin-Secreting CellsABSTRACT
Objective To investigate the protective effect and mechanism of serum containing Euonymus fortunei on the rat pancreatic islet cells. Methods Forty male SD rats were randomly divided into 5 groups (n=8 in each group), including the control group (normal rat islet cells were cultured with normal rat serum), ischemic preconditioning group (abdominal aorta was blocked first and then re-opened before the pancreas was obtained, and the pancreatic islet cells were cultured with normal rat serum), Euonymus fortunei treatment group (normal rat islet cells were cultured with rat serum containing Euonymus fortunei), Euonymus fortunei group and blank group (normal rats were administered orally with Euonymus fortunei extract or distilled water for the preparation of rat serum). Diphenylthiocarbazone (DTZ) staining was utilized to observe and calculate the quantity of islets. Acridine orange (AO)/propidium iodide (PI) staining was adopted to calculate the survival rate of islet cells. The insulin release experiment was performed to calculate the stimulation index (SI) and evaluate islet cell function. The concentration of glutathione (GSH) and nitric oxide (NO) in islet cells was detected using GSH and NO kits. The expression level of inducible nitric oxide synthase (iNOS) messenger RNA (mRNA) was quantitatively measured by reverse transcription polymerase chain reaction (RT-PCR). Results Islet cells were observed in specifically scarlet color after DTZ staining. The quantity of islet cells did not significantly differ among different groups (all P>0.05). Along with the prolongation of culture time, the activity of islet cells in each group was gradually decreased. At 72 h after isolation and culture, compared with the control group, the survival rate of the cells was significantly higher in the Euonymus fortunei treatment group (P<0.05). The insulin release test results demonstrated that compared with the control group, the SI of the ischemic preconditioning and Euonymus fortunei treatment groups was significantly increased (both P<0.05). Compared with the control group, the GSH contents of pancreatic islet cells in the ischemic preconditioning and Euonymus fortunei treatment groups were considerably enhanced, the NO content was significantly decreased, and the expression level of iNOS mRNA was significantly down-regulated (all P<0.05). Conclusions Euonymus fortunei can increase the survival rate of islet cells and enhance the function of pancreatic islets by increasing the level of GSH, down-regulating the expression of iNOS and decreasing the NO production.
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Objective To investigate the isolation and protective effect of a new islet purification solution (IPS)-Optiprep solution on the islet in mouse models. Methods The digested pancreatic islets were divided into the IPS and UW groups according to the islet volume. The pancreatic islets were isolated by the continuous gradient density centrifugation using IPS-Optiprep or UW-Optiprep solutions. The purification efficiency and isolated islet activity of purification solution were compared between two groups. The diabetic mouse models were successfully induced and randomly assigned into three groups. In the experimental group (n=10), the mice received pancreatic islet transplantation using islets isolated and purified by the IPS-Optiprep solution. In the control group (n=10), the mice underwent pancreatic islet transplantation using islets isolated and purified by the UW-Optiprep solution. In the sham surgery group (n=5), the mice merely underwent surgery without pancreatic islet transplantation. Postoperative blood glucose levels were detected and compared among three groups. The blood glucose levels of intraperitoneal glucose tolerance test at postoperative 21 d were statistically compared between the experimental and control groups. The cost of the preparation of two isolation solutions was also compared. Results Compared with the UW group, the islet equivalent (IEQ), islet purity, recovery rate and islet integrity were significantly higher in the IPS group. Islet morphological observation revealed that the islet membrane was complete and the islet diameter in the IPS group was considerably larger than that in the UW group. The activity of purified islets in the UW group was significantly higher than that in the IPS group [(88±5)% vs. (84±3)%, P<0.01]. Compared with the UW-Optiprep solution, identical in vivo islet function was obtained in the IPS-Optiprep solution.The cost of IPS-Optiprep solution was significantly less than that of the UW-Optiprep solution. Conclusions The new IPS-Optiprep solution yields higher islet isolation efficiency, purification, integrity and recovery rate and significantly reduces the purification cost compared with the UW-Optiprep solution. Nevertheless, IPS-Optiprep solution exerts a less protective effect on the activity of islet cells, which is probably correlated with the high islet integrity and the endotoxin in the IPS-Optiprep solution.
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A manutenção da célula de ilhotas in vitro aparece como uma estratégia atraente para aumentar o resultado do transplante de ilhotas pancreáticas. Entretanto, o destino das ilhotas em cultura é determinado pelo equilíbrio entre mediadores pró e antiapoptóticos. Nós mostramos anteriormente que os níveis de HSPB1 são aumentados pela prolactina (PRL) tanto nas células beta pancreáticas humanas quanto nas células de insulinoma murino MIN6. Além disso, mostramos que os efeitos pró- sobrevivência induzidos pela prolactina nas células beta pancreáticas são mediados pela HSPB1. Uma vez que o papel da HSPB1 nas células beta não foi estudado diretamente, procuramos explorar os mecanismos moleculares pelos quais a HSPB1 medeia a citoproteção da célula beta induzida pela PRL. Para isso, células MIN6 derivadas de um insulinoma de camundongo e cultura primária de ilhotas pancreáticas murinas (I), silenciadas ou superexpressando HSPB1 foram submetidas à privação de soro e então pré- tratadas na presença ou na ausência de PRL (300 ng / mL) e expostos a ou citocinas (IL-1ß (0,8 ng / mL), IFN-γ (4 ng / mL) e TNF-α (8 ng / mL) por 16 ou 24 h. Após esses períodos de tempo foi avaliada a viabilidade celular. De fato, as células silenciadas para HSPB1 tiveram maiores porcentagens de morte celular em comparação aos controles. No entanto, a superexpressão de HSPB1 sozinha imita os efeitos citoprotectores da Prolactina em ambas as células MIN6 e nas culturas primárias das ilhotas. Estes resultados mostram o papel fundamental da HSPB1 no efeito citoprotetor inibindo a apoptose inducida pelo tratamento com citocinas pró-inflamatórias. Além disso, os lisados de células Min6 tratadas com citocinas na presença ou na ausência de PRL durante 6 h foram sujeitos a imunoprecipitação de HSPB1. Proteínas coimmunoprecipitadas separadaspor SDS-PAGE e posteriormente identificadas por nano-HPLC acoplado à espectrometria de massas. Células pré-tratadas com PRL apresentaram um enriquecimento de proteínas que coprescipitaram com HSPB1 relacionadas em processos de resistência ao estresse oxidativo, degradação proteica e metabolismo de carboidratos. Células MIN6, silenciadas ou superexpressando HSPB1 foram expostas á menadiona e peróxido de hidrogênio e parâmetros oxidativos foram analisados. O silenciamento de HSPB1 promoveu células mais sensíveis ao estresse oxidativo e levou a uma redução da capacidade antioxidante, enquanto que prolactina induziu citoproteção mediada por HSPB1 contra o estresse oxidativo. A superexpressão de HSPB1, no entanto, levou a efeitos opostos. O tratamento com PRL, o silenciamento ou superexpressão de HSPB1 não mudou a expressão de enzimas antioxidantes, mas os níveis proteicos de HSPB1 estão relacionados com a modulação da razão GSH/GSSG e a atividade de G6PD. Dado de estudos recentes reportam que o perfil respiratório das ilhotas prévias ao transplante pode predizer seu desempenho e que não se sabe nada sobre se a PRL poderia modular a função mitocondrial nas células beta; no presente projeto foi investigado se o tratamento hormonal poderia aumentar a eficiência mitocondrial das células beta. Observamos que o tratamento com citocinas pró-inflamatórias produziu uma diminuição na eficiência do consumo de oxigênio mitocondrial estar relacionado à síntese de ATP. Esses resultados foram significativamente revertidos a valores similares ao obtidos nas células submetidas Às condições de máxima viabilidade após o tratamento com PRL. Além disso, os resultados mostraram que os níveis elevados de HSPB1 medeiam este efeito, uma vez que a falta desta proteína anulou significativamente a recuperação da função mitocondrial induzida pelo tratamento hormonal. Visto que as taxas de síntese de ATP mitocondrial são as responsáveis pela elevação na sua concentração intracelular e que esse evento está diretamente relacionado com a secreção de insulina nas células beta, analisamos se diferentes níveis proteicos de HSPB1 poderia modificar a função secretora de células beta. Para isso foram calculados os índices de estímulo da secreção de insulina em resposta ao aumento da concentraçãode glicose no meio de cultura tanto em células parentais MIN6 como em culturas primárias de ilhotas pancreáticas murinas que foram submetidas ou não ao silenciamento ou superexpressão de HSPB1. Nossos resultados mostraram que nem a presença de citocinas, Prolactina, ou a ausência ou superexpressão de HSPB1 nas culturas celulares analisadas apresentaram diferença significativa em relação aos índices de estímulo da secreção e conteúdo de insulina. Esses resultados sugerem que nem a falta, nem a superexpressão de HSPB1 poderia alterar a função de célula beta. Nós mostramos a relevância da HSPB1 em ambos os efeitos pró- sobrevivência da PRL contra a morte da célula beta induzida tanto por citocinas quanto por indução de estresse oxidativo. Este último efeito poderia também estar relacionado com a participação da HSPB1 na recuperação da função mitocondrial observada após o tratamento hormonal corroborando assim parte dos resultados obtidos nos experimentos de immunoprecipitação. Finalmente, nossos resultados destacam a importância de mais estudos visando um entendimento mais profundo das funções da HSPB1 nas células beta, uma vez que elas poderiam levar à mitigação da morte da célula beta através da regulação positiva de uma via de proteção endógena, que não é dependente da modulação do sistema imunológico
The success of islet transplantation has improved lately. Unfortunately, it is still compromised by cell loss. Maintaining islet cell in vitro appears as an attractive strategy to increase the outcome of pancreatic islet transplantation. However, islet fate in culture is determined by the balance between pro- and anti- apoptotic mediators. We have previously shown that Heat Shock Protein B1 (HSPB1) levels are increased by prolactin (PRL) on both human pancreatic beta cells and MIN6 murine insulinoma cells. Furthermore, we have demonstrated the prolactin-induced pro-survival effects on pancreatic beta-cells are mediated by HSPB1. Since HSPB1 role in beta cells has not been directly studied, we set out to explore the molecular mechanisms by which HSPB1 mediates PRL-induced beta cell cytoprotection. For this purpose, MIN6 insulinoma mouse cells and primary culture of murine pancreatic islets (I) wild type, HSPB1 silenced or overexpressing the chaperone were subjected to serum starvation and then pre-treated in the presence or in the absence of PRL (300 ng/mL) and exposed to or cytokines (IL-1ß (0,8 ng/mL), IFN-γ (4 ng/mL) and TNF-α (8 ng/mL)) for 16 or 24h. Then, we analyse cell viability. HSPB1silenced cells presented higher percentages of cell death compared to controls. However, the overexpression of HSPB1, independently of hormonal treatment, was able mimic the cytoprotective effects of Prolactin. These results point at the key role of HSPB1 in the cytoprotective effect against proinflammatory cytokines-induced beta cell death. In addition, lysates from Min6 cells incubated for 6 hours in the presence of a cocktail of cytokines and/or PRL were subjected to HSPB1 immunoprecipitation. Co-precipitated proteins were identified by SDS-PAGE coupled to mass spectrometry. We found an enrichment of proteins relatedto signaling pathways involved in a response against oxidative and endoplasmic reticulum stress induction. Moreover, we also identified antiapoptotic effects and carbohydrate metabolism related proteins. Indeed, HSPB1 knockdown rendered cells more sensitive to oxidative stress and led to a reduced antioxidant capacity, while prolactin induced an HSPB1- mediated cytoprotection against ROS induced beta-cell apoptosis. One again, HSPB1 overexpression mimic PRL- induced cytoprotection. While hormonal treatment, HSPB1 silencing or overexpression did not change the expression of antioxidant enzymes; this conditions influenced reduced glutathione cell content and G6DP activity. Since recent studies have pointed that islets respiratory profile prior to transplantation may predict their performance; we also investigated whether PRL treatment could increase beta-cell mitochondrial efficiency. We observed a cytokine-induced increase of mitochondrial oxygen consumption rate not related to ATP synthesis, which was significantly decreased upon PRL treatment. HSPB1 was a key mediator of this effect since the lack of this protein significantly abrogated PRL-induced mitochondrial function recovery. The secretory function was then analysed in wild type MIN6 cells as well as in primary cultures of pancreatic islets either HSPB1 silenced or overexpressing the chaperone. Cells were subjected to serum starvation and then pre-treated in the presence or in the absence of PRL and exposed to cytokines for 16 or 24h. We didn´t found significant differences in both glucose induced-insulin secretion and insulin content between the hormonal treatment, HSPB1 silencing or overexpression. These results suggest that neither lack, nor overexpression of HSPB1 could alter beta cell function. Altogether our results have shown the importance of HSPB1 on PRL prosurvival effects as well as on maintenance of mitochondrial efficiency against both cytokine treatment and oxidative-stress-induced beta cell damage. These results are in accordance with the PRL-induced enrichment of HSPB1 interacting proteins displaying functions related to protein degradation, oxidative stress protection or mitochondrial carbohydrate metabolism.Finally, our results outline the importance of further studies aiming at a deeper understanding of HSPB1 functions on beta cells, since they could lead to the mitigation of beta cell death through the up-regulation of an endogenous protective pathway, which is not dependent on the modulation of the immune system
Subject(s)
Prolactin , Cytoprotection , Insulin-Secreting Cells/classification , Islets of Langerhans Transplantation/adverse effects , Apoptosis/physiology , Diabetes Mellitus, Type 1/diagnosisABSTRACT
Objective To identify potential molecule targets of type 2 diabetes using weighted gene co-expression network analysis. Methods Microarray data of type 2 diabetes (GSE38642) were downloaded from Gene Expression Omnibus of NCBI, including 9 type 2 diabetic patients, 9 pre-diabetic patients ( 6%≤HbA1C<6.5%), and 31 normal controls (HbA1C<6%). Using weighted gene co-expression network analysis (WGCNA) package in R, the weighted gene co-expression network was built and significant modules related to clinical traits were identified. Then, functional and pathway enrichment analysis were conducted for genes in the most significant modules using GeneAnswers package in R. Upstream transcription factor enrichment analysis were conducted using TRANSFAC database. The hub genes and upstream transcription factors were selected as potential molecule targets of type 2 diabetes. Results 34 modules were identified in the co-expression network. Green module was positive correlated with HbA1C(R＝0.47, P＝1×10－4). The enriched functions were cell adhesion, extracellular matrix disassembly, etc. The enriched KEGG pathways were Pancreatic secretion, Focal adhesion, etc. ITGA6, ZAK, and YBX3 are hub genes of Green module. Brown module was negative correlated with HbA1C(R＝0.46, P＝1×10－4). The enriched functions were synapse, transmembrane transporter activity, etc. The enriched KEGG pathways were Insulin secretion, Dopaminergic synapse, etc. The upstream transcription factors PAX6, REST, and PDX1 of Brown module might play important roles. 30 hub genes, including SLC4A10, ELAVL4, and SYT14, were identified in Brown module. The relationships between these genes and type 2 diabetes were confirmed by previously published studies. Conclusion Important genes related to type 2 diabetes can be filtered out from transcriptome profiles using gene co-expression analysis. Our finding might provide a novel insight into the underlying molecular mechanism of type 2 diabetes.
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Aim To investigate the effect of baicalein on insulin secretion from rat islets and the underlying mechanism. Methods Pancreatic islets were obtained from the pancreas of male Wistar rats by collagenase P digestion and histopaque-1077 density gradient separa-tion. Single islet cells were dispersed from pancreatic islets by Dispase II digestion. Insulin secretion experi-ment was applied to observe insulin release after baica-lein stimulation. To study the potential mechanism, calcium imaging technique and patch-clamp experiment were applied to measure intracellular Ca2+ concentra-tion and voltage-dependent potassium channel currents (Kv). Results In 16. 7mmol·L-1 glucose, baica-lein accelerated insulin secretion in a dose-dependent manner. Baicalein promoted the intracellular Ca2+ con-centration. The patch-clamp experiment showed that baicalein inhibited Kv current in a dose-dependent manner. Conclusion Baicalein can increase the in-tracellular Ca2+ concentration by inhibiting Kv chan-nels and eventually promoting insulin secretion.
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Objective To investigate whether pancreatic islet transplantation in combination with bone mesenchymal stem cells (MSC) transplantation can promote the vascularization surrounding the transplant pancreatic islet.Methods The non-obese diabetic (NOD) mice were utilized as the recipients and randomly divided into pancreatic islet transplantation combined with MSC transplantation group (co-transplantation group,n=6),pancreatic islet transplantation group(n=6),MSC transplantation group(n=6) and sham transplantation group (n=3).The variation in blood glucose level and survival rate post-transplantation of NOD mice in each group was observed.The proliferation and apoptosis of the transplant pancreatic islet in the pancreatic islet transplantation group and co-transplantation group at 1,2 and 4 weeks after pancreatic islet transplantation were analyzed by 5-ethynyl-2'-deoxyufidine (EdU) and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL).The vascular density surrounding the transplanted pancreatic islet in the pancreatic islet transplantation group and co-transplantation group at postoperative 2,4 and 8 weeks were observed under light microscope and quantitatively analyzed by histochemical and immunohistochemical staining.Results Both MSC combined with pancreatic islet transplantation and pancreatic islet transplantation significantly improved the blood glucose level and enhanced the survival rate of NOD mouse models after transplantation.In addition,it could accelerate the regeneration of pancreatic islet cells and decrease cell apoptosis.MSC combined with pancreatic islet transplantation significantly enhanced the vascular density surrounding the transplant pancreatic islet compared with pancreatic islet transplantation alone.Conclusions MSC transplantation can accelerate the vascularization surrounding the transplant pancreatic islet,increase the blood supply and protect the function and activity of the transplant pancreatic islet.
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Objective:To investigate the influence of α cells and glucagon-like peptide l (GLP-1) in the function of β cells (INS-1 cells) in the rats,and to elucidate the possible mechanism of α cells and INS-1 cells transplantation in influencing hypoglycemia.Methods:The proliferation abilities of INS-1 cells after treated with 10％,20％ and 30％ islet α-cell conditioned medium and 0.03,0.30,3.00,30.0 mg · L-1 of GLP-1 were analyzed by MTT assay.The levels of insulin secretion of INS-1 cells after treated with 10％,20％,30％ α cells,α-cell conditioned medium and different concentrations of GLP-1 were analyzed by enzyme linked immunosorbent assay (ELISA).The concentrations of Ca2+ in INS-1 cells after treated with high glucose and GLP-1 were analyzed by laser confocal microscope.The expression levels of insulin protein after treated with different concentrations of islet α-cell conditioned medium and different concentrations of GLP-1 were detected by Western blotting methed.After the INS-1 cells,the mixture of INS-1 cells and α cells were transplanted into the left renal capsule of the nude mice,the blood glucose levels and the kidney morphology were observed.The levels of insulin/glucagon in the transplanted cells were detected by immunohistochemistry.Results:Compared with control group,both of α-cell conditioned media and GLP-1 promoted the INS-1 cell proliferation and insulin secretion (P ＜ 0.05).The laser confocal microscope results revealed that GLP-1 stimulated the increased intracellular Ca2+ concentration in INS-1 cells (P＜ 0.05).Compared with control group,there was no significant difference in the expression levels of insulin protein in the insulin-1 cells after treated with islet α cell conditioned medium and GLP-1 (P＞0.05).Compared with pre transplantation,the blood glucose level in the transplanted INS-1 cells was significantly decreased at 35 d after renal capsul trasplantation (P＜0.05),and even hypoglycemia presented renal capsular in the diabetic nude mice;the transplantation site was obviously swollen.However,the levels of blood glucose had no change of the diabetic rats after transplated with the mixture of INS-1 and α cells (P＜0.05).The expression of insulin and glucagon in the INS-1 transplanted cells were found by immunohistochemistry staining.Conclusion:Pancreatic islet α cells and their secretions can promote the INS-1 cell proliferation and insulin secretion,and the mixture of INS-1 cells and α cells transplanted under the renal capsule of the diabetic nude mice can reduce the hypoglycemic effect of INS-1 cell transplantation which might be related to the INS-1 cells that can express both of insulin and glucagon genes.
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Objective:To investigate the influence of α cells and glucagon-like peptide l (GLP-1) in the function of β cells (INS-1 cells) in the rats,and to elucidate the possible mechanism of α cells and INS-1 cells transplantation in influencing hypoglycemia.Methods:The proliferation abilities of INS-1 cells after treated with 10％,20％ and 30％ islet α-cell conditioned medium and 0.03,0.30,3.00,30.0 mg · L-1 of GLP-1 were analyzed by MTT assay.The levels of insulin secretion of INS-1 cells after treated with 10％,20％,30％ α cells,α-cell conditioned medium and different concentrations of GLP-1 were analyzed by enzyme linked immunosorbent assay (ELISA).The concentrations of Ca2+ in INS-1 cells after treated with high glucose and GLP-1 were analyzed by laser confocal microscope.The expression levels of insulin protein after treated with different concentrations of islet α-cell conditioned medium and different concentrations of GLP-1 were detected by Western blotting methed.After the INS-1 cells,the mixture of INS-1 cells and α cells were transplanted into the left renal capsule of the nude mice,the blood glucose levels and the kidney morphology were observed.The levels of insulin/glucagon in the transplanted cells were detected by immunohistochemistry.Results:Compared with control group,both of α-cell conditioned media and GLP-1 promoted the INS-1 cell proliferation and insulin secretion (P ＜ 0.05).The laser confocal microscope results revealed that GLP-1 stimulated the increased intracellular Ca2+ concentration in INS-1 cells (P＜ 0.05).Compared with control group,there was no significant difference in the expression levels of insulin protein in the insulin-1 cells after treated with islet α cell conditioned medium and GLP-1 (P＞0.05).Compared with pre transplantation,the blood glucose level in the transplanted INS-1 cells was significantly decreased at 35 d after renal capsul trasplantation (P＜0.05),and even hypoglycemia presented renal capsular in the diabetic nude mice;the transplantation site was obviously swollen.However,the levels of blood glucose had no change of the diabetic rats after transplated with the mixture of INS-1 and α cells (P＜0.05).The expression of insulin and glucagon in the INS-1 transplanted cells were found by immunohistochemistry staining.Conclusion:Pancreatic islet α cells and their secretions can promote the INS-1 cell proliferation and insulin secretion,and the mixture of INS-1 cells and α cells transplanted under the renal capsule of the diabetic nude mice can reduce the hypoglycemic effect of INS-1 cell transplantation which might be related to the INS-1 cells that can express both of insulin and glucagon genes.
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BACKGROUND:Acute pancreatitis is a common inflammatory disease mediated by pancreatic acinar cel s injury, and is mainly characterized by leukocyte infiltration. N-acetylcysteine can control leukocyte migration and regulate inflammation in some serious inflammatory diseases. OBJECTIVE:To investigate the protective effects of N-acetylcysteine in rat model of acute pancreatitis caused by sodium taurocholate. METHODS:Ninety Sprague-Dawley rats were randomly divided into three groups:normal control group, acute pancreatitis group and N-acetylcysteine group. Except normal control group, acute pancreatitis model was established in the other two groups by retrograde injection of sodium taurocholate into major duodenal papil a. Rats in the N-acetylcysteine group were treated with N-acetylcysteine intravenously through the tail vein. RESULTS AND CONCLUSION:After acute pancreatitis model was established, plasma amylase levels in the models were significantly higher than that in the normal control rats (P<0.05). Interleukin-1β,-6,-10, and tumor necrosis factorαexpression levels were also obviously higher than that in the normal control rats (P<0.05). Immunohistochemical staining demonstrated that N-acetylcysteine was mainly expressed in the islet cel s, and the pancreatic expression of N-acetylcysteine was down-regulated at both the mRNA and protein levels during the course of acute pancreatitis. N-acetylcysteine administration significantly reduced plasma amylase levels, myeloperoxidase activity, pro-inflammatory cytokine production, and pancreas and lung tissue damages. Furthermore, N-acetylcysteine administration did not cause significant inhibition of nuclear factor-κB activation in the pancreas. N-acetylcysteine is capable of improving damage of pancreas and lung, and exerting anti-inflammatory effects in rats with severe acute pancreatitis.
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Objective: To test two water soluble extracts (aqueous and ethanolic) obtained from the leaves ofVitex doniana in normal and streptozotocin-induced diabetic rats for their effects on pancreatic endocrine tissues and serum marker enzymes for a period of 21 d. Methods: A total of 55 rats divided into 11 groups of 5 rats each were assigned into diabetic and non-diabetic groups and followed by a daily administration of ethanolic and aqueous extracts for 21 d. Group 1 was the normal control while group 7 was treated with standard drug.Results:The histopathological studies of the diabetic rats indicated increase in the volume density of islets, percent of β-cells and size of islet in the groups that received the plant extracts, which suggested regeneration of β-cells along with β-cells repairs, as compared with the non-treated diabetic control which showed complete degeneration of the islet cells. There was significant reduction (P0.01) in the serum activities of marker enzymes was observed for non-diabetic treated rats. Results of total bilirubin, direct bilirubin and unconjugated bilirubin showed that diabetic control group was significantly higher (P0.01) in total bilirubin and direct bilirubin compared with the normal control.Conclusion:This herbal therapy appears to bring about repair/regeneration of the endocrine pancreas and hepatic cells protection in the diabetic rat.
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<p><b>OBJECTIVE</b>To test two water soluble extracts (aqueous and ethanolic) obtained from the leaves of Vitex doniana in normal and streptozotocin-induced diabetic rats for their effects on pancreatic endocrine tissues and serum marker enzymes for a period of 21 d.</p><p><b>METHODS</b>A total of 55 rats divided into 11 groups of 5 rats each were assigned into diabetic and non-diabetic groups and followed by a daily administration of ethanolic and aqueous extracts for 21 d. Group 1 was the normal control while group 7 was treated with standard drug.</p><p><b>RESULTS</b>The histopathological studies of the diabetic rats indicated increase in the volume density of islets, percent of β-cells and size of islet in the groups that received the plant extracts, which suggested regeneration of β-cells along with β-cells repairs, as compared with the non-treated diabetic control which showed complete degeneration of the islet cells. There was significant reduction (P<0.05) in the serum activities of marker enzymes, alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase in diabetes treated rats, whereas an insignificant increase (P>0.01) in the serum activities of marker enzymes was observed for non-diabetic treated rats. Results of total bilirubin, direct bilirubin and unconjugated bilirubin showed that diabetic control group was significantly higher (P<0.05) in total bilirubin and unconjugated bilirubin compared with treated groups while non-diabetic treated groups showed no significant increase (P>0.01) in total bilirubin and direct bilirubin compared with the normal control.</p><p><b>CONCLUSION</b>This herbal therapy appears to bring about repair/regeneration of the endocrine pancreas and hepatic cells protection in the diabetic rat.</p>
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This study was aimed to evaluate effect of Qinghua Granules (QHG) on glycometabolism, pancreatic islet function and oxidative stress in type-2 diabetics with heat syndrome. A total of 60 cases of type-2 diabetics with heat syndrome (according to the Syndrome Element Syndrome Differentiation) were enrolled in the clinic of the Department of Endocrinology and Metabolism, Shuguang Hospital Affiliated to Shanghai University of Tradi-tional Chinese Medicine. The average age of enrolled cases was (57.9 ± 6.9) years. Enrolled cases were randomly divided into the treatment group and the control group. The original hypoglycemic plan was continued to use. In the treatment group, QHG was administrated. And in the control group, placebo was given. The administration dosage in both groups was one package per day. The treatment course was 12 weeks. The fasting and postpran-dial (120 min after standard meal) blood samples before and after medication were collected. The main evalua-tion indexes were fasting plasma glucose (FPG), postprandial plasma glucose (PPG) and hemoglobin A1c (HbA1c). The secondary evaluation indexes were homeostasis model assessment (HOMA2-%B, HOMA2-%S, HOMA2%-IR), superoxide dismutase (SOD), glutathione peroxidase (GSH-PX), maleic dialdehyde (MDA), total cholesterol (TC), triglyceride (TG), high-density lipoprotein (HDL) and low-density lipoprotein (LDL). The anal-ysis of variance was used in the comparison of efficacy between two groups . The results showed that HbA1c in the treatment group was obviously reduced, and HOMA2-%B was obviously increased. There was no significant changes in the control group ( P = 0 . 044 , P = 0 . 016 ) . In the treatment group , SOD increased obviously , MDA reduced obviously. There was no significant change in the control group. There was difference b etween two groups (P = 0.011, P = 0.049). There was no change on blood lipids or other evaluation indexes. It was conclud-ed that QHG is effective in the improvement of glycometabolism, islet β-cell functions and oxidative stress in type-2 diabetics with heat syndrome .
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The pancreatic tissues from patients with islet cell hyperplasia,insulinoma,and pancreatic adenocarcinoma,as well as normal pancreatic tissues were embedded with paraffin,serial sections were cut and mounted on glass slides.Immunohistochemical staining was carried out with N-myc down-stream regulated gene 2 (Ndrg2) monoclonal antibody by means of ABC method,and Western blotting was carried out to detect the expression and distribution of Ndrg2.The results showed that Ndrg2 positive immunoreactivity was mainly localized in the cytoplasm of islet cell,being similar to the localization of insulin positive immunoreactivity.The number and volume of pancreatic islets were increased in the patients with islet cell hyperplasia,and Ndrg2 expression was also increased.Western blotting results showed that the expression of Ndrg2 in the pancreas of patients with islet cell hyperplasia was increased compared with normal group.The above results suggest that Ndrg2 may play an important role in performing physiological function of islet cells.
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O transplante de ilhotas microencapsuladas constitui uma alternativa terapêutica interessante para o Diabetes Mellitus tipo 1, permitindo um melhor controle glicêmico e eliminando a necessidade de imunossupressão. Entretanto, a manutenção a longo prazo da viabilidade das células-ß ainda é um desafio. No isolamento, a perda da matriz extracelular e as condições hipóxicas subsequentes afetam decisivamente a sobrevivência e funcionalidade das ilhotas. Objetivo Para diminuir o estresse sobre o enxerto, levando a um sucesso prolongado do transplante, propôs-se a adição de perfluorocarbono (PFC) ou laminina (LN), moléculas associadas respectivamente à oxigenação e interações célula-célula, ao biomaterial baseado em alginato, Biodritina, adequado ao encapsulamento celular. Metodologia Para testar a estabilidade das formulações PFC-Biodritina e LN-Biodritina, microcápsulas foram submetidas a diferentes estresses (rotacional, osmótico, temperatura e cultura) por 7 e 30 dias. A pureza do biomaterial foi avaliada pela coincubação com macrófagos murinos RAW264.7, por 3, 9 e 24h, quando a ativação dos macrófagos foi observada pela expressão gênica de IL- 1ß e TNFα. Microcápsulas implantadas i.p. em camundongos foram recuperadas após 7 ou 30 dias, para análises de biocompatibilidade. A expressão de níveis de mRNA (bax, bad, bcl-2, bcl-XL, xiap, caspase 3, mcp1/ccl2, hsp70, ldh, insulina 1 e 2), proteínas (Bax, Bcl-XL e Xiap) e a atividade de Caspase3 foram avaliadas em ilhotas microencapsuladas com PFC- e LN-Biodritina, após cultura de 48h em condições de normóxia e hipóxia (<2% O2). Camundongos diabéticos foram transplantados com ilhotas encapsuladas nas diferentes formulações e os animais foram monitorados pelas variações de massa corporal, glicêmicas e pela funcionalidade do enxerto (TOTGs). As ilhotas foram recuperadas de animais normo ou hiperglicêmicos e uma análise de biocompatibilidade das cápsulas foi realizada, assim como a avaliação funcional das células-ß. Após o explante, a glicemia dos animais normoglicêmicos foi monitorada para se atestar a eficiência das ilhotas transplantadas. Resultados Microcápsulas de PFC- e LN-Biodritina são tão estáveis e biocompatíveis quanto as de Biodritina. Para ilhotas encapsuladas em ambos os materiais, em normóxia ou hipóxia, observou-se uma modulação gênica que sugere proteção contra apoptose. Adicionalmente, encontrou-se uma diminuição na expressão de genes indicadores de estresse (mcp1, hsp70). Uma diminuição nos níveis de mRNA de ldh foi vista para PFC-Biodritina, mas o oposto foi encontrado para LN-Biodritina. As diferenças encontradas na expressão proteica sugerem o mesmo padrão anti-apoptótico. Caspase3 não foi modulada por nenhum biomaterial. Nos experimentos de transplante, apenas LN-Biodritina levou reversão prolongada do diabetes, com 60% dos animais normoglicêmicos, 198 dias pós-cirurgia, comparado a 9% do grupo Biodritina. O TOTG demonstrou que camundongos transplantados com ilhotas encapsuladas secretaram mais insulina do que controles, 60 (LN-Biodritina) ou 100 (PFC- e LN-Biodritina) dias pós-cirurgia. O explante restabeleceu a hiperglicemia nos camundongos. Microcápsulas recuperadas de animais hiperglicêmicos apresentavam uma extensa adesão celular. Testes de secreção de insulina in vitro demonstraram que somente ilhotas do grupo normoglicêmico responderam às variações da concentração de glicose. Conclusão A adição de moléculas bioativas à Biodritina é capaz de diminuir o estresse em ilhotas isoladas e tem o potencial de melhorar a terapia pelo transplante de ilhotas
Transplantation of microencapsulated islets represents an attractive therapeutical approach to treat type 1 Diabetes Mellitus, accounting for an improved glycemic control and the abolishment of immunosuppressive therapies. However, maintenance of long-term ß-cell viability remains a major problem. During islet isolation, the loss of extracellular matrix interactions and the hypoxic conditions thereafter dramatically affect ß-cell survival and function. Objective To lessen the burden of islet stress and achieve a better outcome in islet transplantation we tested the addition of perfluorocarbon (PFC) or laminin (LN), molecules associated respectively with oxygenation and cell-cell interaction, to Biodritin, an alginate-based material suitable for cell microencapsulation. Methodology To test the stability of PFC-Biodritin and LN-Biodritin composites, microcapsules were subjected to different stresses (rotational, osmotic, temperature and culture) for 7 and 30 days. To assess biomaterial purity microcapsules were co-incubated with RAW264.7 murine macrophage cell line for 3, 9 and 24h and macrophage activation was detected through mRNA levels of IL-1ß and TNFα. Microcapsules were implanted i.p. in mice and retrieved after 7 or 30 days, for biocompatibility analyses. Gene expression at mRNA (bax, bad, bcl-2, bcl-XL, xiap, caspase 3, mcp1/ccl2, hsp70, ldh, insulin 1 and 2) and protein (Bax, Bcl-XL and Xiap) levels, together with Caspase3 activity, were evaluated in islets microencapsulated in PFC- or LN-Biodritin, upon culturing for 48h in normoxic or hypoxic (<2% O2) conditions. Diabetic mice were transplanted with PFC- or LN-Biodritin microencapsulated islets, followed by assessments of body weight, glycemia and graft function by oral glucose tolerance tests (OGTTs). Microencapsulated islets were retrieved from normoglycemic or hyperglycemic mice and biocompatibility analyses of the beads together with a functional assessment of the graft followed. After graft removal, normoglycemic animals had their glycemias monitored to attest the efficacy of the transplanted islets. Results PFC- and LN-Biodritin microcapsules were as stable and biocompatible as Biodritin. For both biomaterials in normoxia and hypoxia a modulation in gene expression was observed in islets associated with a protection against apoptosis. Also, a decreased expression of stress-related genes (mcp1, hsp70) was evidenced. ldh mRNA levels were down-regulated in PFC-Biodritin microencapsulated islets but upregulated in the presence of LN. Increased levels of insulin mRNA were observed. The differences seen in protein expression indicated the same anti-apoptotic pattern. Caspase3 activity was not different between groups. Concerning diabetes reversal experiments, only mice transplanted with LN-Biodritin microencapsulated islets presented a better outcome, with 60% remaining euglycemic at 198 days post-surgery, compared with 9% for the Biodritin group. OGTT showed that mice transplanted with encapsulated islets secreted more insulin than normal mice, 60 (LN-Biodritin) or 100 days (PFC- and LN-Biodritina) posttransplant. Hyperglycemia was achieved after the retrieval of microcapsules showing graft efficacy. Retrieved microcapsules revealed an extensive overgrowth in most beads from hyperglycemic mice. A static glucose stimulated insulin secretion test revealed that only islets from normoglycemic subjects were able to secrete insulin according to glucose concentration. Conclusion- The addition of bioactive molecules to Biodritin may lessen the stress of isolated islets and have the potential to improve islet transplantation therapy.