Objective To investigate the effect of alpha 1-antitrypsin (A1AT) concerning in reducing the injury of transplanted islets by pancreas exocrine cells and promoting proliferation of the pancreas B cells.Method The pancreases of mice were digested with collagenase,islets were isolated artificially,and pancreatic exocrine cells were collected.In purified islet group (n =6),100 islets were seeded into a 6 well culture plate.In experimental group(n =6),100 islets were co-cultured with equal volume of pancreas exocrine cells,and 0.5 mg/mL A1AT was added into a 6-well culture plate.In control group(n =6),100 islets were co-cultured with equal volume of pancreas exocrine cells.After 48 h,insulin content of islets in each well and trypsin concentration in the supernatant of each well were measured.The islets were cultured in low sugar and high sugar 1640 medium,then glucose stimulated insulin secretion (GSIS) test was carried out.In vivo,8-9-week old male BALB/C mice were induced with STZ (190 mg/kg body weight,i.p) to establish the diabetic model and randomly divided into two groups.In experimental(n =10) and control(n =10) groups,250 islets and the equal volume of pancreatic exocrine cells were transplanted into different regions of left kidney subcapsule,resepctively.The experimental group was injected with A1AT (83 mg/kg,qd,i.p) for 28 days after operation,and the control group was injected with the same amount of normal saline (qd,i.p) for 28 days.Both two groups were given EDU (5 μg/g,qd,i.p) for 28 days.The blood glucose level was monitored continually.Nephrectomies were performed after 28 days.The expression of anti-amylase antibodies in the renal subcapsule was detected by immunohistochemical staining,and the proliferation of islet beta cells was examined using immunofluorescence staining.Result Insulin levels and insulin stimulation index in the control group were decreased as compared with those in the purified islet group; those in the experimental group were higher than in the control group,but lower than in the purified islet group.Trypsin concentration in the control group was increased as compared with the purified islet group,that in the experimental group was lower than the control group,but higher than in the purified islet group (all P＜0.01).After islets transplantation,the blood glucose levels in control and experimental groups were normal,but those in the control group recovered later than in the experimental group (P＜0.01).At 3rd day after nephrectomy,the blood glucose levels were ＞21 mmol/L in both two groups.A large number of anti-amylase antibody-positive cells were found in the renal subcapsule in the control group while little seen in the experimental group after 28 days.The immunofluorescence showed that the insulin +/EDU + B cells in the experimental group were more than those in the control group.Conclusion Conclusion Co-culture of islets and pancreatic exocrine cells with A1AT can prevent islet cells from damage caused by trypsin.A1AT could inhibit the secretion of pancreatic amylase from pancreatic acinar cells and promote proliferation of islet beta cells.

Objective To investigate the expression and clinical significances of miR-215 and runtrelated protein1 (RUNX1) in retinoblastoma (RB),and to study the regulation effect of miR-215 on RUNX1 in the retinoblastoma cell line PMC-RB.Methods The expressions of miR-215 and RUNX1 in the tumor tissue,non tumor tissues adjacent to cancer,human RB cell line FMC-RB and human normal retinal vascular endothelial cell line ATCC of RB patients were detected by quantitative real-time polymerase chain reaction (qRT-PCR).miR-215 mimics (miR-215-mimic),miR-NC,si-RUNX1 and si-NC were transfected into FMC-RB cell line respectively.Cell proliferation,migration and invasion ability were measured respectively,thus detecting the regulation effect of miR-215 on RUNX1.Results The expression of miR-215 in RB tissues was significantly lower than that in non tumor tissues adjacent to cancer,while the mRNA expression of RUNX1 was higher than that in non tumor tissues adjacent to cancer (P ＜ 0.05).The expression of miR-215 in PMC-RB cells was lower than that in ATCC,while the mRNA expression of RUNX1 was higher than that in ATCC (P ＜0.05).The expression of miR-215 and RUNX1 in RB tumor tissues were closely related to the clinicopathological features of optic nerve infiltration,tumor tissue differentiation and lymph node metastasis (P ＜ 0.05).Cell proliferation,migration and invasion in miR-215-mimic group were significantly lower than those in miR-NC group (P ＜ 0.05).In transfected 3' untranslated region (3 'UTR)-Wt cells,the luciferase activity in miR-215-mimic group was lower than that in miR-NC group (P ＜ 0.05);the expression level of RUNX1 protein in transfected miR-215-mimic cells was lower than that in transfected miR-NC cells (P ＜ 0.05).Cell proliferation,migration and invasion in si-RUNX1 group were all lower than those in si-NC group (P ＜ 0.05).There was a negative correlation between mRNA expression level of miR-215 and RUNX1 in RB tumor tissues.Conclusions During the occurrence and development of RB,the down-regulation of miR-215 expression can promote malignant progression of tumor by targeting RUNX1.miR-215 can be used as a biological markers and therapeutic target for RB diagnosis.

Transposable elements (TEs) have no longer been totally considered as "junk DNA" for quite a time since the continual discoveries of their multifunctional roles in eukaryote genomes. As one of the most important and abundant TEs that still active in human genome, Alu, a SINE family, has demonstrated its indispensable regulatory functions at sequence level, but its spatial roles are still unclear. Technologies based on 3C (chromosome conformation capture) have revealed the mysterious three-dimensional structure of chromatin, and make it possible to study the distal chromatin interaction in the genome. To find the role TE playing in distal regulation in human genome, we compiled the new released Hi-C data, TE annotation, histone marker annotations, and the genome-wide methylation data to operate correlation analysis, and found that the density of Alu elements showed a strong positive correlation with the level of chromatin interactions (hESC: r = 0.9, P < 2.2 × 10(16); IMR90 fibroblasts: r = 0.94, P < 2.2 × 10(16)) and also have a significant positive correlation with some remote functional DNA elements like enhancers and promoters (Enhancer: hESC: r = 0.997, P = 2.3 × 10(-4); IMR90: r = 0.934, P = 2 × 10(-2); Promoter: hESC: r = 0.995, P = 3.8 × 10(-4); IMR90: r = 0.996, P = 3.2 × 10(-4)). Further investigation involving GC content and methylation status showed the GC content of Alu covered sequences shared a similar pattern with that of the overall sequence, suggesting that Alu elements also function as the GC nucleotide and CpG site provider. In all, our results suggest that the Alu elements may act as an alternative parameter to evaluate the Hi-C data, which is confirmed by the correlation analysis of Alu elements and histone markers. Moreover, the GC-rich Alu sequence can bring high GC content and methylation flexibility to the regions with more distal chromatin contact, regulating the transcription of tissue-specific genes.
Alu Elements ; genetics ; Base Composition ; Binding Sites ; Cell Line ; Chromatin ; chemistry ; genetics ; metabolism ; CpG Islands ; DNA ; metabolism ; Databases, Genetic ; Enhancer Elements, Genetic ; genetics ; Genome, Human ; Histones ; metabolism ; Humans ; Methylation

Myoclonus dystonia syndrome (MDS) is an inherited movement disorder, and most MDS-related mutations have so far been found in the ε-sarcoglycan (SGCE) coding gene. By generating SGCE-knockout (KO) and human 237 C > T mutation knock-in (KI) mice, we showed here that both KO and KI mice exerted typical movement defects similar to those of MDS patients. SGCE promoted filopodia development in vitro and inhibited excitatory synapse formation both in vivo and in vitro. Loss of function of SGCE leading to excessive excitatory synapses that may ultimately contribute to MDS pathology. Indeed, using a zebrafish MDS model, we found that among 1700 screened chemical compounds, Vigabatrin was the most potent in readily reversing MDS symptoms of mouse disease models. Our study strengthens the notion that mutations of SGCE lead to MDS and most likely, SGCE functions to brake synaptogenesis in the CNS.