Type 2 diabetes is characterized by progressive decline in pancreatic beta cell function and persistent insulin resistance. Decreased beta cell mass and amyloid deposits in the islet are the pathological hallmark of the disease. Preserved beta cell function is the most important determinant of glucose disposal, even after adjustment for insulin sensitivity, which might modulate beta cell functi...

Pancreatic beta-cell survival is critical in the setting of diabetes as well as in islet transplantation. Transgenic mice overexpressing parathyroid hormone-related protein (PTHrP) targeted to beta-cells using the rat insulin II promoter (RIP) display hyperinsulinemia, hypoglycemia, and islet hyperplasia, without a concomitant increase in beta-cell proliferation rate or enlargement of individua...

BACKGROUND The mass of pancreatic beta-cells varies according to increases in insulin demand. It is hypothesized that functionally heterogeneous beta-cell subpopulations take part in this process. Here we characterized two functionally distinct groups of beta-cells and investigated their physiological relevance in increased insulin demand conditions in rats. METHODS Two rat beta-cell populati...

beta 2 glycoprotein i (β2gpi) is a single chain 50 kda highly glycosylated glycoprotein at an approximate concentration of 4 μm in cells. the abundance of this protein in plasma and its high state of preservation indicate the important role of this protein in mammalian. in addition, β2gpi has a particular structure in the fifth domain, and is categorized as the major antigen recognized by autoa...

Intermittent restraint stress delays hyperglycemia in ZDF rats better than pair feeding. We hypothesized that intermittent stress would preserve beta-cell mass through distinct mechanisms from food restriction. We studied temporal effects of intermittent stress on beta-cell compensation during pre-, early, and late diabetes. Six-week-old obese male ZDF rats were restraint-stressed 1 h/day, 5 da...

We study the interplay between diversity and noise in a 3D network of FitzHugh-Nagumo elements, with topology dimensions chosen to model pancreatic beta-cell cluster, as an example excitable cell network. Our results show that are not equivalent sources disorder but have different effects on dynamics. Their synchronization mechanisms may act independently one another or synergistically, dependi...

In type 2 diabetes, the beta cells of the pancreas fail to produce enough insulin to meet the body's demand, in part because of an acquired decrease in beta-cell mass. In adults, pancreatic beta-cell mass is controlled by several mechanisms, including beta-cell replication, neogenesis, hypertrophy, and survival. Here, I discuss evidence supporting the notion that increased beta-cell apoptosis i...

One week of treatment with EGF and gastrin (EGF/G) was shown to restore normoglycemia and to induce islet regeneration in mice treated with the diabetogenic agent alloxan. The mechanisms underlying this regeneration are not fully understood. We performed genetic lineage tracing experiments to evaluate the contribution of beta cell neogenesis in this model. One day after alloxan administration, ...

OBJECTIVE The objectives of the study were to determine whether the cell cycle transcription factor, FoxM1, is required for glucose homeostasis and beta-cell mass expansion in maternal islets during pregnancy and whether FoxM1 is essential for placental lactogen (PL)-induced beta-cell proliferation. RESEARCH DESIGN AND METHODS beta-Cell mass, beta-cell proliferation, and glucose homeostasis w...

OBJECTIVE Most knowledge on human beta-cell cycle control derives from immunoblots of whole human islets, mixtures of beta-cells and non-beta-cells. We explored the presence, subcellular localization, and function of five early G1/S phase molecules-cyclins D1-3 and cdk 4 and 6-in the adult human beta-cell. RESEARCH DESIGN AND METHODS Immunocytochemistry for the five molecules and their relati...