Islet cell stress induced by insulin-degrading enzyme deficiency promotes regeneration and protection from autoimmune diabetes.

Tuning of protein homeostasis through mobilization of the unfolded protein response (UPR) is key to the capacity of pancreatic beta cells to cope with variable demand for insulin. Here, we asked how insulin-degrading enzyme (IDE) affects beta cell adaptation to metabolic and immune stress. C57BL/6 and autoimmune non-obese diabetic (NOD) mice lacking IDE were exposed to proteotoxic, metabolic, and immune stress.

Interferon-α promotes neo-antigen formation and preferential HLA-B-restricted antigen presentation in pancreatic β-cells.

Interferon (IFN)-α is the earliest cytokine signature observed in individuals at risk for type 1 diabetes (T1D), but its effect on the repertoire of HLA Class I (HLA-I)-bound peptides presented by pancreatic β-cells is unknown. Using immunopeptidomics, we characterized the peptide/HLA-I presentation in resting and IFN-α-exposed β-cells. IFN-α increased HLA-I expression and peptide presentation, including neo-sequences derived from alternative mRNA splicing, post-translational modifications - notably glutathionylation - and protein -splicing.

Stearoyl CoA desaturase is a gatekeeper that protects human beta cells against lipotoxicity and maintains their identity.

Aims/hypothesis: During the onset of type 2 diabetes, excessive dietary intake of saturated NEFA and fructose lead to impaired insulin production and secretion by insulin-producing pancreatic beta cells. The majority of data on the deleterious effects of lipids on functional beta cell mass were obtained either in vivo in rodent models or in vitro using rodent islets and beta cell lines. Translating data from rodent to human beta cells remains challenging.

Author Correction: Cytotoxic and regulatory roles of mucosal-associated invariant T cells in type 1 diabetes.

In the version of this Article originally published, the asterisks indicating statistical significance were missing from Supplementary Figure 6; the file with the correct figure is now available.

Design and experimental force analysis of a novel elliptical vibration assisted orthopedic oscillating saw.

Orthopedic oscillating saws (OOSs) are widely used for plane processing in orthopedic surgery such as knee and hip replacement. However, sawing has been associated with bone breakthrough and necrosis problems. In this paper, a novel elliptical vibration assisted OOS was designed to achieve a low cutting force under the condition of deepening cut depth and reducing cutting speed, based on the analysis of brittle fractures of the bone and elliptical vibration assisted cutting kinematics.

MondoA Is an Essential Glucose-Responsive Transcription Factor in Human Pancreatic β-Cells.

Although the mechanisms by which glucose regulates insulin secretion from pancreatic β-cells are now well described, the way glucose modulates gene expression in such cells needs more understanding. Here, we demonstrate that MondoA, but not its paralog carbohydrate-responsive element-binding protein, is the predominant glucose-responsive transcription factor in human pancreatic β-EndoC-βH1 cells and in human islets. In high-glucose conditions, MondoA shuttles to the nucleus where it is required for the induction of the glucose-responsive genes arrestin domain-containing protein 4 (ARRDC4) and thioredoxin interacting protein (TXNIP), the latter being a protein strongly linked to β-cell dysfunction and diabetes.

Cytotoxic and regulatory roles of mucosal-associated invariant T cells in type 1 diabetes.

Type 1 diabetes (T1D) is an autoimmune disease that results from the destruction of pancreatic β-cells by the immune system that involves innate and adaptive immune cells. Mucosal-associated invariant T cells (MAIT cells) are innate-like T-cells that recognize derivatives of precursors of bacterial riboflavin presented by the major histocompatibility complex (MHC) class I-related molecule MR1. Since T1D is associated with modification of the gut microbiota, we investigated MAIT cells in this pathology.

Molecular phenotyping of multiple mouse strains under metabolic challenge uncovers a role for in glucose-induced insulin secretion.

Objective: In type 2 diabetes (T2D), pancreatic β cells become progressively dysfunctional, leading to a decline in insulin secretion over time. In this study, we aimed to identify key genes involved in pancreatic beta cell dysfunction by analyzing multiple mouse strains in parallel under metabolic stress.

Methods: Male mice from six commonly used non-diabetic mouse strains were fed a high fat or regular chow diet for three months.

Ex Vivo Expansion and Differentiation of Human and Mouse Fetal Pancreatic Progenitors Are Modulated by Epidermal Growth Factor.

A comparative analysis of mouse and human pancreatic development may reveal common mechanisms that control key steps as organ morphogenesis and cell proliferation and differentiation. More specifically, understanding beta cell development remains an issue, despite recent progress related to their generation from human embryonic and induced pluripotent stem cells. In this study, we use an integrated approach, including prospective isolation, organ culture, and characterization of intermediate stages, and report that cells from human and mouse fetal pancreas can be expanded in the long term and give rise to hollow duct-like structures in 3D cultures.