Regulation of beta cell replication

Regulation of pancreatic beta-cell mass.

Beta-cell mass regulation represents a critical issue for understanding diabetes, a disease characterized by a near-absolute (type 1) or relative (type 2) deficiency in the number of pancreatic beta cells. The number of islet beta cells present at birth is mainly generated by the proliferation and differentiation of pancreatic progenitor cells, a process called neogenesis. Shortly after birth, ...

Glucose Mediated Regulation of Beta Cell Proliferation

The pancreatic beta cell, as the sole source of circulating insulin, is indispensible for normal glucose metabolism. All forms of diabetes are characterized by insufficient insulin to meet metabolic needs, and inadequate beta cell mass is present in most forms of diabetes. Beta cell regenerative therapies provide one potential avenue for the prevention or cure of diabetes. Study of the pathways...

Transplanted beta cell response to increased metabolic demand. Changes in beta cell replication and mass.

We determined the capacity of transplanted beta cells to modify their replication and mass when stimulated by changes in metabolic demand. Five groups of Lewis rats were studied: group 1 (Tx-Px) had a 95% pancreatectomy 14 d after transplantation of 500 islets; group 2 (Px-Tx) had a 95% pancreatectomy 14 d before transplantation of 500 islets; group 3 (Tx) was transplanted with 500 islets; grou...

The Cell Cycle: Regulation, Apoptosis, Mitosis and Replication of DNA

Regulation of DNA replication during the yeast cell cycle.

One central event that must occur exactly once per cell division cycle is the replication of the genomic DNA. One defining observation of the eukaryotic cell cycle is that the nuclear DNA replicates during a short period (the S phase) and that during that period each part of every chromosome is entirely replicated. Although there are many origins of DNA replication per chromosome, and it is kno...