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Chronic inflammation promotes pancreatic β-cell decompensation to insulin resistance because of local accumulation of supraphysiologic interleukin 1β (IL-1β) levels. However, the underlying molecular mechanisms remain elusive. We show that miR-503-5p is exclusively upregulated in islets from humans with type 2 diabetes and diabetic rodents because of its promoter hypomethylation and increased local IL-1β levels. β-Cell–specific miR-503 transgenic mice display mild or severe diabetes in a time- and expression-dependent manner. By contrast, deletion of the miR-503 cluster protects mice from high-fat diet–induced insulin resistance and glucose intolerance. Mechanistically, miR-503-5p represses c-Jun N-terminal kinase–interacting protein 2 (JIP2) translation to activate mitogen-activated protein kinase signaling cascades, thus inhibiting glucose-stimulated insulin secretion (GSIS) and compensatory β-cell proliferation. In addition, β-cell miR-503-5p is packaged in nanovesicles to dampen insulin signaling transduction in liver and adipose tissues by targeting insulin receptors. Notably, specifically blocking the miR-503 cluster in β-cells effectively remits aging-associated diabetes through recovery of GSIS capacity and insulin sensitivity. Our findings demonstrate that β-cell miR-503-5p is required for the development of insulin resistance and β-cell decompensation, providing a potential therapeutic target against diabetes. Article Highlights: Promoter hypomethylation during natural aging permits miR-503-5p overexpression in islets under inflammation conditions, conserving from rodents to humans. Impaired β-cells release nanovesicular miR-503-5p to accumulate in liver and adipose tissue, leading to their insulin resistance via the miR-503-5p/insulin receptor/phosphorylated AKT axis. Accumulated miR-503-5p in β-cells impairs glucose-stimulated insulin secretion via the JIP2-coordinated mitogen-activated protein kinase signaling cascades. Specific blockage of β-cell miR-503-5p improves β-cell function and glucose tolerance in aging mice. [ABSTRACT FROM AUTHOR]

Identifying saline soils is of great importance for protecting land resources and for the sustainable development of agriculture. Total soil salinity (TSS) is the most commonly used indicator for determining soil salinization, but the application of soil geochemical data is rarely reported. In general, there is a significant relationship between TSS and the content of soil-soluble Na, which can be estimated by the difference between the bulk-soil Na2O content and its background value. In this study, the partial least squares regression (PLSR) method was employed to calculate the Na2O background value via a regression model between Na2O and SiO2, Al2O3, TFe2O3, Cr, Nb, and P in a 1:250,000 scale regional geochemical data set of soils in Jilin Province, NE China. We defined δNa as the difference between the bulk-soil Na2O value and the regression background value, which can be used as a geochemical indicator to identify saline soils. One hundred and five samples with known TSS contents in the study area were selected to test the capability of the indicator δNa. The result shows that the identification accuracy can be up to 75%, indicating that the indicator can provide a new means for saline soil identification. [ABSTRACT FROM AUTHOR]

Objective: To explore the anatomy and injuries features of the thumb collateral ligamentat the metacarpophalangeal (MCP) joints., Methods: The study was reviewed and approved by an institutional review board of hospital. Clinical imaging data of 7 healthy volunteers who without injuries and 20 patients with thumb collateral ligament injuries were retrospectively analyzed. All subjects underwent magnetic resonance examination, then comparative analysis of the normal anatomy and the thumb collateral ligament injury at MCP joints of MRI features in healthy volunteers and patients with injury. Imaging findings were compared with the surgical results and confirmed by followed up in patients., Results: Seven volunteers without ligament injures showed homogeneous low-signal-intensity on T1-weighted and proton fat saturation sequence (PD-FS) images. The average thickness of the ulnarcollateral ligament is about 2.0 to 2.3 mm, however, the normal radial collateral ligament is thinner, the average thickness is about 1.4-1.5 mm. There were 20 patients with thumb collateral ligament injuresat MCP joints, including 12 cases of ulnar collateral ligament injury and 8 cases of radial collateral ligament injury, which demonstrated poor definition, discontinuity and heterogeneously increased signal intensity in proton fat saturation sequence (PD-FS) of the involved collateral ligament. There was edema in the soft tissues surrounding the injured sites., Conclusion: MRI is an accurate method for evaluation of the anatomy and pathologic conditions of the thumb collateral ligamentsat MCP joints, and it is a useful tool for early diagnosis and treatment of the thumb collateral ligaments injuries.