GIP and the gut-bone axis – Physiological, pathophysiological and potential therapeutic implications
Publication date: Available online 9 November 2019Source: PeptidesAuthor(s): Signe Stensen, Lærke Smidt Gasbjerg, Mads Marstrand Helsted, Bolette Hartmann, Mikkel Bring Christensen, Filip Krag KnopAbstractThe influence by gut-derived hormones on bone remodelling appears increasingly important as research on the enteroendocrine-osseous axis accelerates. Glucose-dependent insulinotropic polypeptide (GIP) is secreted from the gut and potentiates insulin secretion in a glucose-dependent manner. GIP has, like the two other gut-derived hormones, glucagon-like peptide 1 and glucagon-like peptide 2, been shown to affect bone remo...
Source: Peptides - November 21, 2019 Category: Biochemistry Source Type: research
The influence of Glucose-dependent Insulinotropic Polypeptide (GIP) on human adipose tissue and fat metabolism: implications for obesity, type 2 diabetes and Non-Alcoholic Fatty Liver Disease (NAFLD)
Publication date: Available online 20 November 2019Source: PeptidesAuthor(s): Sravan K. Thondam, Daniel J. Cuthbertson, John P.H. WildingAbstractGlucose-dependent insulinotropic polypeptide (GIP) and glucagon like peptide (GLP-1) are the two incretin hormones secreted by the enteroendocrine system in response to nutrient ingestion. Compared with GLP-1, GIP is less well studied as a hormone or as a potential pharmacological treatment. Beyond its insulinotropic effects in the pancreas, GIP has important biological actions in many other tissues but its role in dietary fat metabolism and lipid storage in adipose tissue has bee...
Source: Peptides - November 21, 2019 Category: Biochemistry Source Type: research
Cellular mechanisms governing Glucose-dependent insulinotropic polypeptide secretion
Publication date: Available online 19 November 2019Source: PeptidesAuthor(s): Frank Reimann, Eleftheria Diakogiannaki, Catherine E Moss, Fiona M. GribbleAbstractGlucose-dependent insulinotropic polypeptide (GIP) is a gut hormone secreted from the upper small intestine, which plays an important physiological role in the control of glucose metabolism through its incretin action to enhance glucose-dependent insulin secretion. GIP has also been implicated in postprandial lipid homeostasis. GIP is secreted from enteroendocrine K-cells residing in the intestinal epithelium. K-cells sense a variety of components found in the gut ...
Source: Peptides - November 20, 2019 Category: Biochemistry Source Type: research
GIP analogues and the treatment of obesity-diabetes
Publication date: Available online 19 November 2019Source: PeptidesAuthor(s): Clifford J. BaileyAbstractThe potential application of glucose-dependent insulinotropic polypeptide (gastric inhibitory polypeptide, GIP) in the management of obesity and type 2 diabetes has been controversial. Initial interest in the therapeutic use of GIP was dampened by evidence that its insulinotropic activity was reduced in type 2 diabetes and by reports that it increased glucagon secretion and adipose deposition in non-diabetic individuals. Also, attention was diverted away from GIP by the successful development of glucagon-like peptide-1 (...
Source: Peptides - November 20, 2019 Category: Biochemistry Source Type: research
Effects on Pancreatic Beta and other Islet Cells of the Glucose-dependent Insulinotropic Polypeptide
Publication date: Available online 18 November 2019Source: PeptidesAuthor(s): Rabeet Khan, Alejandra Tomas, Guy A. RutterAbstractGlucose-dependent insulinotropic polypeptide (GIP) is a gut-derived incretin that, in common with glucagon-like peptide-1 (GLP-1), has both insulin releasing and extra-pancreatic glucoregulatory actions. GIP is released in response to glucose or fat absorption and acts on the GIP receptor (GIPR) to potentiate insulin release from pancreatic beta cells. GIP has also been shown to promote beta cell survival and stimulate the release of GLP-1 from islet alpha cells. There is now evidence to suggest ...
Source: Peptides - November 20, 2019 Category: Biochemistry Source Type: research
Effects of Angiotensin III on c-Jun N terminal Kinase in Wistar and Hypertensive Rat Vascular Smooth Muscle Cells
This study is the first to show Ang III effects on the JNK MAPK pathway in VSMCs and the role of JNK in Ang III-mediated cellular proliferation. These findings impart key information for the understanding of Ang III functions, especially in VSMCs and possible cardiovascular diseases. (Source: Peptides)
Source: Peptides - November 16, 2019 Category: Biochemistry Source Type: research
Effects of long-acting GIP, xenin and oxyntomodulin peptide analogues on alpha-cell transdifferentiation in insulin-deficient diabetic GluCreERT2;ROSA26-eYFP mice
Publication date: Available online 16 November 2019Source: PeptidesAuthor(s): Dipak Sarnobat, R. Charlotte Moffett, Victor A. Gault, Neil Tanday, Frank Reimann, Fiona M. Gribble, Peter R. Flatt, Nigel IrwinAbstractEnzyme-resistant long-acting forms of the gut-derived peptide hormones, glucose-dependent insulinotropic polypeptide (GIP), xenin and oxyntomodulin (Oxm) have been generated, and exert beneficial effects on diabetes control and pancreatic islet architecture. The current study has employed alpha-cell lineage tracing in GluCreERT2;ROSA26-eYFP transgenic mice to investigate the extent to which these positive pancrea...
Source: Peptides - November 16, 2019 Category: Biochemistry Source Type: research
Effect of (m)VD-hemopressin against Aβ1-42-induced oxidative stress and apoptosis in mouse hippocampal neurons
This study aimed to clarify the mechanism by which VD protects hippocampal neurons against Aβ1-42-induced impairment. Our results showed that VD inhibited oxidative stress injury induced by Aβ1-42, as demonstrated by the VD-induced reversal of the upregulation of reactive oxygen species (ROS) and the intracellular lipid peroxidation product malondialdehyde (MDA) and the downregulation of the activities of the antioxidative enzymes catalase (CAT) and glutathione peroxidase (GSH-PX) in mouse hippocampal neurons. We also found that VD restored the decrease in cell growth and viability induced by Aβ1-42 and reversed Aβ1-42...
Source: Peptides - November 13, 2019 Category: Biochemistry Source Type: research
Blockade of gastric inhibitory polypeptide (GIP) action as a novel means of countering insulin resistance in the treatment of obesity-diabetes
Publication date: Available online 13 November 2019Source: PeptidesAuthor(s): Nigel Irwin, Victor A. Gault, Finbarr P.M. O’Harte, Peter R. FlattAbstractGastric inhibitory polypeptide (GIP) is a 42 amino acid hormone secreted from intestinal K-cells in response to nutrient ingestion. Despite a recognised physiological role for GIP as an insulin secretagogue to control postprandial blood glucose levels, growing evidence reveals important actions of GIP on adipocytes and promotion of fat deposition in tissues. As such, blockade of GIP receptor (GIPR) action has been proposed as a means to counter insulin resistance, and imp...
Source: Peptides - November 13, 2019 Category: Biochemistry Source Type: research
Catestatin in defense of oxidative-stress-induced apoptosis: a novel mechanism by activating the beta2 adrenergic receptor and PKB/Akt pathway in ischemic-reperfused myocardium
Publication date: Available online 12 November 2019Source: PeptidesAuthor(s): Song-Yun Chu, Fen Peng, Jie Wang, Lin Liu, Lei Meng, Jing Zhao, Xiao-Ning Han, Wen-Hui DingAbstractApoptosis induced by oxidative stress is one of the most important cardiomyocytes losses during ischemia-reperfusion (I/R). Catestatin (CST) has been demonstrated to have the anti-oxidative capacity in vitro. We hypothesized that CST intervention could reduce apoptosis of cardiomyocytes induced by oxidative stress in I/R. In Langendorff-perfused rat heart global I/R model, CST was introduced at the reperfusion stage. In comparison to the control gro...
Source: Peptides - November 12, 2019 Category: Biochemistry Source Type: research
Peptides and their receptors: Treasures for pharmacological interventions
Publication date: Available online 10 November 2019Source: PeptidesAuthor(s): Karl-Heinz Herzig (Source: Peptides)
Source: Peptides - November 12, 2019 Category: Biochemistry Source Type: research
GIP and the gut-bone axis - physiological, pathophysiological and potential therapeutic implications
Publication date: Available online 9 November 2019Source: PeptidesAuthor(s): Signe Stensen, Lærke Smidt Gasbjerg, Mads Marstrand Helsted, Bolette Hartmann, Mikkel Bring Christensen, Filip Krag KnopAbstractThe influence by gut-derived hormones on bone remodelling appears increasingly important as research on the enteroendocrine-osseous axis accelerates. Glucose-dependent insulinotropic polypeptide (GIP) is secreted from the gut and potentiates insulin secretion in a glucose-dependent manner. GIP has, like the two other gut-derived hormones, glucagon-like peptide 1 and glucagon-like peptide 2, been shown to affect bone remo...
Source: Peptides - November 10, 2019 Category: Biochemistry Source Type: research
Combinatorial inhibition of Angiotensin converting enyme, Neutral endopeptidase and Aminopeptidase N by N-methylated peptides alleviates blood pressure and fibrosis in rat model of dexamethasone-induced hypertension
In this study, N-methylated peptide inhibitors F-N(Me)H-L, V-N(Me)F-R and R-N(Me)V-Y were synthesized against ACE, NEP and APN respectively, using their respective physiological substrates. F-N(Me)H-L inhibited ACE activity with an IC50 of 83 nmol/L, V-N(Me)F-R inhibited NEP activity with an IC50 of 1.173 µmol/L and R-N(Me)V-Y inhibited APN activity with an IC50 of 3.94 nmol/L respectively. Further, the anti-hypertensive effect of N-methylated peptides was evaluated using rat model of dexamethasone-induced hypertension. Individual peptides and their cocktail treatment were started from day 6 of the study period and ...
Source: Peptides - November 10, 2019 Category: Biochemistry Source Type: research
Cardiovascular effects of DWORF (dwarf open reading frame) peptide in normal and ischaemia/reperfused isolated rat hearts
In conclusion, we provide the first evidence that DWORF has coronary vasoconstrictor actions in normal hearts and when administered during reperfusion in an ex-vivo model of cardiac I/R injury, and also exhibits positive cardiac inotropic activity in the latter setting. DWORF’s effect on ventricular contractile function appears to be dependent on the L-type Ca2+ channel, whereas Rho-Kinase activity may be related to the coronary vasoconstrictor effects of DWORF. (Source: Peptides)
Source: Peptides - November 9, 2019 Category: Biochemistry Source Type: research
Metabolism of GIP and the contribution of GIP to the glucose-lowering properties of DPP-4 inhibitors
Publication date: Available online 7 November 2019Source: PeptidesAuthor(s): Carolyn F DeaconAbstractGlucose-dependent insulinotropic polypeptide (GIP) is a gastrointestinal hormone with insulinotropic and glucagonotropic actions, and is believed to be the more physiologically important incretin hormone in healthy humans. Together with the other incretin hormone, glucagon-like peptide-1 (GLP-1), it plays an important role in regulating glucose homeostasis. Both GLP-1 and GIP are substrates of the enzyme dipeptidyl peptidase-4 (DPP-4), and DPP-4 inhibitors, which potentiate their effects on glycaemic control, are now used t...
Source: Peptides - November 9, 2019 Category: Biochemistry Source Type: research
