Metformin increases the serine-phosphorylation of Tiam-1 by AMPK and induces interaction between Tiam-1 and this website 14-3-3. Pharmacologic inhibition of AMPK blocks this interaction, indicating that 14-3-3 may be required for induction of Tiam-1 by AMPK. Metformin also increases the phosphorylation of p21-activated kinase 1 (PAK1), a direct downstream target of Rac1, dependent on AMPK. Tiam-1 is down-regulated at high glucose concentrations in cultured cells and in the db/db mouse model of hyperglycemia. Furthermore, Tiam-1 knock-down blocked metformin-induced increase in glucose uptake. These findings
suggest that metformin promotes cellular glucose uptake in part through Tiam-1 induction. (C) 2013 Elsevier Inc. All rights reserved.”
“Following consumption of a meal, plasma glucose check details levels are managed by insulin and glucagon release. The postprandial release of insulin and glucagon is regulated by the incretin hormones glucagon-like peptide 7 (GLP-1) and gastric inhibitory polypeptide/glucose-dependent insulinotropic polypeptide (GIP), which are rapidly inactivated by the action of dipeptidyl peptidase 4 (DPP IV) proteases. Postprandial levels of the incretin hormones are severely reduced in patients with type 2 diabetes, leading to compromised plasma glucose homeostasis. Preventing inactivation of incretin hormones in order to increase their
postprandial duration of action should have potential in the management of diabetes. With this in mind, a number of DPP IV inhibitors have been prepared Nirogacestat and shown to successfully lower
glycated hemoglobin levels and correct fasting plasma glucose concentrations in patients with type 2 diabetes. Dutogliptin tartrate is a small soluble DPP IV inhibitor that was developed by Phenomix and is currently in phase II/III clinical trials as monotherapy or in combination with other existing treatments for the management of type 2 diabetes.”
“SOCS1 profoundly influences the development and peripheral homeostasis of CD8(+) T cells but has less impact on CD4(+) T cells. Despite the moderate influence of SOCS1 in the development of the total CD4 T-cell lineage, we show here that SOCS1 deficiency resulted in a 10-fold increase in Foxp3(+) CD4(+) T cells in the thymus. Increased numbers of Foxp3(+) thymocytes occurred in mice with T-cell-specific ablation of SOCS1, suggesting that the effect is T-cell intrinsic. This increase in Foxp3(+) CD4(+) cells in SOCS1-deficient mice also occurred in the absence of IFN-gamma or/and IL-7 signaling. Increase in CD25(+)CD4(+) T cells in the absence of SOCS1 could be partly due to enhanced survival by CD25(+)CD4(+) cells, to a lesser degree CD25(-)CD4(+) T cells, from SOCS1-deficient mice with or without T-cell growth factors. Immunology and Cell Biology (2009) 87, 473-480; doi: 10.1038/icb.2009.