In Vitro and In Vivo Effects of Natural Putative Secretagogues of Glucagon-Like Peptide-1 (GLP-1)

Glucagon-like peptide-1 (GLP-1) is an intestinal hormone with well-established glucose-lowering activity. The in vitro and in vivo actions of natural putative secretagogues of GLP-1 were investigated. The acute GLP-1 releasing activity of olive leaf extract (OLE), glutamine (GLN), alpha casein (ACAS), beta casein (BCAS) and chlorogenic acid (CGA) were assessed in STC-1 cells and C57BL/6 mice. All compounds except ACAS significantly increased acute in vitro GLP-1 secretion (66-386%; P

Plasma concentrations of glucagon-like peptide-2 in adult patients with treated and untreated coeliac disease

Coeliac disease is a common chronic inflammatory enteropathy characterized by villous atrophy and crypt hyperplasia in the small intestine. The mechanism of the intestinal damage in coeliac disease remains unclear. Glucagon-like peptide (GLP)-2 is an enterotrophic peptide that causes crypt hyperplasia and intestinal cell proliferation. We postulate that GLP-2 may be involved in the mucosal changes found in coeliac disease.

Selective Targeting of Glucagon-Like Peptide-1 Signalling As a Novel Therapeutic Approach for Cardiovascular Disease in Diabetes

Glucagon-like peptide-1 (GLP-1) is an incretin hormone whose glucose-dependent insulinotropic actions have been harnessed as a novel therapy for glycaemic control in type 2 diabetes. Although it has been known for some time that the GLP-1 receptor is expressed in the cardiovascular system where it mediates important physiological actions, it is only recently that specific cardiovascular effects of GLP-1 in the setting of diabetes have been described. GLP-1 confers indirect benefits in cardiovascular disease (CVD) under both normal and hyperglycaemic conditions via reducing established risk factors, such as hypertension, dyslipidaemia and obesity, which are markedly increased in diabetes. Emerging evidence indicates that GLP-1 also exerts direct effects on specific aspects of diabetic CVD, such as endothelial dysfunction, inflammation, angiogenesis and adverse cardiac remodelling. However, the majority of studies have employed experimental models of diabetic CVD and information on the effects of GLP-1 in the clinical setting are limited although several large-scale trials are ongoing. It is clearly important to gain a detailed knowledge of the cardiovascular actions of GLP-1 in diabetes given the large number of patients currently receiving GLP-1 based therapies. This review will therefore discuss current understanding of the effects of GLP-1 on both cardiovascular risk factors in diabetes and direct actions on the heart and vasculature in this setting, and the evidence implicating specific targeting of GLP-1 as a novel therapy for CVD in diabetes.