Search

Corticotropin-releasing factor (CRF) and the urocortins (UCN1, UCN2, and UCN3) belong to the CRF family of peptides and are the major regulators of the adaptive response to internal and external stresses. The actions of CRF and UCNs are mediated through two receptor subtypes: CRF receptor 1 (CRFR1) and CRFR2. Their physiological roles, among other functions, include the regulation of food intake and anxiety-like behavior. In this review, we describe the progress that has been made towards understanding how anxiety- and depression-like behavior and food intake are regulated by CRF, UCN1, UCN2, and UCN3.

Hydrogen (H2) acts as a therapeutic antioxidant. However, there are few reports on H2 function in other capacities in diabetes mellitus (DM). Therefore, in this study, we investigated the role of H2 in glucose transport by studying cultured mouse C2C12 cells and human hepatoma Hep-G2 cells in vitro, in addition to three types of diabetic mice [Streptozotocin (STZ)-induced type 1 diabetic mice, high-fat diet-induced type 2 diabetic mice, and genetically diabetic db/db mice] in vivo. The results show that H2 promoted 2-[ H14C]-deoxy-D-glucose (2-DG) uptake into C2C12 cells via the translocation of glucose transporter Glut4 through activation of phosphatidylinositol-3-OH kinase (PI3K), protein kinase C (PKC), and AMP-activated protein kinase (AMPK), although it did not stimulate the translocation of Glut2 in Hep G2 cells. H2 significantly increased skeletal muscle membrane Glut4 expression and markedly improved glycemic control in STZ-induced type 1 diabetic mice after chronic intraperitoneal (i.p.) and oral (p.o.) administration. However, long-term p.o. administration of H2 had least effect on the obese and non-insulin-dependent type 2 diabetes mouse models. Our study demonstrates that H2 exerts metabolic effects similar to those of insulin and may be a novel therapeutic alternative to insulin in type 1 diabetes mellitus that can be administered orally. [ABSTRACT FROM AUTHOR]

Obestatin, a 23-amino-acid peptide, is derived from the preproghrelin precursor. Obestatin was identified in 2005 as a hormone regulating food intake and energy, and having opposite effects to those of ghrelin. However, as studies have progressed, many disputes on the physiological function of obestatin have emerged. The food intake suppressive effects of obestatin have not been replicated in many studies. Nonetheless, many biological roles of obestatin have been revealed, and obestatin is thought to be associated with a variety of biological functions such as feeding, drinking, incretion, memory, and sleep, and with neuropsychiatric manifestations. The biological effects of obestatin will be reviewed in this article. [ABSTRACT FROM AUTHOR]