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BackgroundN6-methyladenosine (m6A) modification is a critical epigenetic modification in eukaryotes and involves several biological processes and occurrences of diseases. However, the roles and regulatory mechanisms of m6A regulators in osteoporosis (OP) remain unclear. Thus, the purpose of this study is to explore the roles and mechanisms of m6A regulators in OP.MethodsThe mRNA and microRNA (miRNA) expression profiles were respectively obtained from GSE56815, GSE7158, and GSE93883 datasets in Gene Expression Omnibus (GEO). The differential expression of 21 m6A regulators between high-bone mineral density (BMD) and low-BMD women was identified. Then, a consensus clustering of low-BMD women was performed based on differentially expressed (DE)-m6A regulators. The m6A-related differentially expressed genes (DEGs), the differentially expressed miRNAs (DE-miRNAs), and biological functions were investigated. Moreover, a weighted gene co-expression network analysis (WGCNA) was constructed to identify the OP-related hub modules, hub genes, and the functional pathways. Then, an m6A regulator–target–pathway network and the competing endogenous RNA (ceRNA) network in key modules were constructed. A least absolute shrinkage and selection operation (LASSO) Cox regression model and a Support Vector Machine-Recursive Feature Elimination (SVM-RFE) model were constructed to identify the candidate genes for OP prediction. The receiver operator characteristic (ROC) curves were used to validate the performances of predictive models and candidate genes.ResultsA total of 10,520 DEGs, 13 DE-m6A regulators, and 506 DE-miRNAs between high-BMD and low-BMD women were identified. Two m6A-related subclusters with 13 DE-m6A regulators were classified for OP. There were 5,260 m6A-related DEGs identified between two m6A-related subclusters, the PI3K-Akt, MAPK, and immune-related pathways, and bone metabolism was mainly enriched in cluster 2. Cell cycle-related pathways, RNA methylation, and cell death-related pathways were significantly involved in cluster 1. Five modules were identified as key modules based on WGCNA, and an m6A regulator–target gene–pathway network and the ceRNA network were constructed in module brown. Moreover, three m6A regulators (FTO, YTHDF2, and CBLL1) were selected as the candidate genes for OP.ConclusionM6A regulators play an important role in the occurrences and diagnosis of OP.

Objective To investigate the improvement and effect of the method of islet extraction in mice. Methods According to different islet extraction methods, all mice were randomly divided into the common bile duct puncture group (n=100) and common bile duct puncture combined with in situ pancreatic injection group (combined injection group, n=100). Common bile duct puncture combined with in situ pancreatic injection was utilized as the modified method. The islets were selected and purified under stereomicroscope. The morphology and purification of islets were identified. The islet yield and success rate of islet extraction were statistically compared between two groups. The survival of islets after 1 week culture in vitro was analyzed, and the insulin secretion function of islets after 24 h and 4 d culture in vitro was evaluated. Results Compared with the common bile duct puncture group, the islet yield in the combined injection group was significantly increased (P < 0.001). The success rate of islet extraction in both groups was 83% with no statistical significance (P > 0.05). The islets extracted by common bile duct puncture combined with in situ pancreatic injection had intact morphology, high purity and high activity. The survival rate of newly isolated islets was nearly 100% after 24 h culture in vitro. After 1~5 d culture in vitro, the islet cells survived well. After 6 d culture in vitro, the islets showed central death. After culture in vitro for 24 h and 4 d, the islet function of the mice was normal after high glucose stimulation. Conclusions Common bile duct puncture combined with in situ pancreatic injection can increase the islet yield, and the obtained islet cells have high activity and proper function.