Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01275 (glucagon)
 26,492 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Glucagon Like Peptide 2 (GLP-2) has been proposed as an important regulatory hormone in nutrient absorption. The present study was conducted in human infants with intestinal dysfunction undergoing surgery, correlating postprandial GLP-2 levels with intestinal length, nutrient absorption, and patient outcome. We hypothesized that GLP-2 levels would be inversely related to nutrient absorption; we further hypothesized that post prandial GLP-2 levels would be predictive of the ability to wean patients from total parenteral nutrition (TPN), and tolerance of enteral feeding. Infants prospectively identified with nutrient malabsorption following intestinal surgery were monitored and after initiation of feeds GLP-2 levels were measured in the fed state. Intestinal length was recorded intraoperatively and nutrient absorption was quantified using both a balance study, and carbohydrate probe method. 12 infants had GLP-2 levels successfully measured; two patients had repeated studies. Average gestational age was 32.7 +/- 3.4 wk, age at testing was 1.7 +/- 1.4 mo and average weight was 3.5 +/- 1.1 kg. Causes of intestinal loss were necrotizing enterocolitis, atresia and volvulus. Five patients had severe short bowel syndrome (<50% of normal small intestinal length), 3 died. GLP-2 levels were best correlated with residual small intestinal length (r2 = 0.75). Correlations with total intestinal length including colon were less significant; residual colon appeared to not contribute to measurable GLP-2 production. GLP-2 levels were well correlated with tolerance of enteral feeds. Contradicting the initial hypothesis, GLP-2 levels were directly correlated with nutrient absorptive capacity (correlation with fat absorption: r2 = 0.72, carbohydrate = 0.50 and protein = 0.54 respectively). There were no apparent changes in GLP-2 levels with gestational or postnatal age. As a corollary to the correlation with bowel length, a postprandial level of 15 pmol/L appeared to be discriminatory; infants with postprandial GLP-2 levels of > 15 pmol/L were able to be weaned from total parenteral nutrition, while 3 of 4 infants who had GLP-2 levels less than 15 could not be weaned by one year. These results show that in infants with intestinal dysfunction, GLP-2 levels are correlated with residual small bowel length and nutrient absorption, and may be predictive of outcome. In contrast to adults with intact colon and SBS, infants with SBS and intact colon do not appear able to produce GLP-2 in response to feeding stimulation. Further studies are suggested to examine the ontogeny of the GLP-2 axis and the possible therapeutic role of GLP-2 supplementation.
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PMID:GLP-2 levels in infants with intestinal dysfunction. 1520 2

Short bowel syndrome-associated intestinal failure (SBS-IF) as a consequence of extensive surgical resection of the gastrointestinal (GI) tract results in a chronic reduction in intestinal absorption. The ensuing malabsorption of a conventional diet with associated diarrhea and weight loss results in a dependency on parenteral nutrition and/or intravenous fluids (PN/IV). A natural compensatory process of intestinal adaptation occurs in the years after bowel resection as the body responds to a lack of sufficient functional nutrient-processing intestinal surface area. The adaptive process improves bowel function but is a highly variable process, yielding different levels of symptom control and PN/IV independence among patients. Intestinal rehabilitation is the strategy of maximizing the absorptive capacity of the remnant GI tract. The approaches for achieving this goal have been limited to dietary intervention, antidiarrheal and antisecretory medications, and surgical bowel reconstruction. A targeted pharmacotherapy has now been developed that improves intestinal absorption. Teduglutide is a human recombinant analogue of glucagon-like peptide 2 that promotes the expansion of the intestinal surface area and increases the intestinal absorptive capacity. Enhanced absorption has been shown in clinical trials by a reduction in PN/IV requirements in patients with SBS-IF. This article details the clinical considerations and best-practice recommendations for intestinal rehabilitation, including optimization of fluids, electrolytes, and nutrients; the integration of teduglutide therapy; and approaches to PN/IV weaning.
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PMID:Increased intestinal absorption in the era of teduglutide and its impact on management strategies in patients with short bowel syndrome-associated intestinal failure. 2334 99

The 33 amino acid peptide hormone GLP-2 is produced by enteroendocrine L-cells, the density of which is highest in the ileum and the colon, in response to the presence of nutrients in the lumen. The biological effect of GLP-2 is mediated by activation of a G-protein-coupled 7-transmembrane receptor. GLP-2 receptors are expressed in the brainstem, lungs, stomach, small intestine and colon, but not in the heart. It has been shown in several animal studies that GLP-2 infusion increases intestinal blood flow and that this increase is confined to the small intestine. The aim of the three studies, on which the thesis is based, was to investigate basic physiological effects of GLP-2, in healthy volunteers and in SBS patients, with focus on the effects on mesenteric blood flow, blood flow at other vascular sites and effects on cardiac parameters. These parameters have been evaluated after both meal stimulation and GLP-2 administration. The studies showed the following results: Blood flow: In all three studies, blood flow changes in the SMA after GLP-2 administration were similar regarding changes over time and degree of change. Blood flow changes were similar to changes seen after a standard meal. Only RI changes were registered in all three studies, but the TAMV changes in study 2 and 3 had similar characteristics. Cardiovascular parameters: In all three studies no significant changes in blood pressure were registered in relation to GLP-2 administration. In study two and three, where cardiac parameters also were registered by impedance cardiography, increases in CO and SV were seen. Plasma GLP-2: There were, as expected, supraphysiological GLP-2 plasma levels after SC administration. All three studies have shown rapid changes in mesenteric blood flow after administration GLP-2. The changes have been the same both in regards to time to maximum changes (increase) and relatively close in regards to maximum extent of change. The changes in the SBS patients were less than in the healthy test subjects. The findings leave no doubt about that GLP-2 is a potent regulator of upper splanchnic blood flow. The study findings also support the notion that the observed increased mesenteric blood flow, isolated to the SMA, is secondary to the metabolic responses to GLP-2, and that these are likely due to a paracrine action by GLP-2 acting on GLP-2R bearing cells such as enteric neurons, probably expressing NO. In conclusion GLP-2 increases mesenteric blood flow in healthy subjects and in SBS patients, the increase is equivalent to a standard meal and dose dependent. The blood flow is not increased at other arterial vascular sites. GLP-2 does not acutely alter blood pressure, but increases, probably as compensation, pulse rate and cardiac output. GLP-2 induced vascular response in the superior mesenteric artery is related with the length of remaining intestine in SBS patients. The effect is therefore likely to reflect the metabolic activity in the tissue rather than direct effect on the vascular system.
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PMID:GLP-2 and mesenteric blood flow. 2367 68

Glucagon-like peptide 2 [GLP-2] is a 33-amino acid peptide released from the mucosal enteroendocrine L-cells of the intestine. The actions of GLP-2 are transduced by the GLP-2 receptor [GLP-2R], which is localized in the neurons of the enteric nervous system but not in the intestinal epithelium, indicating an indirect mechanism of action. GLP-2 is well known for its trophic role within the intestine and interest in GLP-2 is now reviving based on the approval of the GLP-2R agonist for treatment of short bowel syndrome [SBS]. Recently it also seems to be involved in glucose homeostasis. The aim of this review is to outline the importance of neuroendocrine peptides, specifically of GLP-2 in the enteric modulation of the gastrointestinal function and to focus on new works in order to present an innovative picture of GLP-2.
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PMID:GLP-2: what do we know? What are we going to discover? 2521 18

Extensive intestinal resection impairs the absorptive capacity and results in short-bowel syndrome-associated intestinal failure (SBS-IF), when fluid, electrolyte, acid-base, micro-, and macronutrient homeostasis cannot be maintained on a conventional oral diet. Several factors, including the length and site of the resected intestine, anatomical conformation of the remnant bowel, and the degree of postresection intestinal adaptation determine the disease severity. While mild SBS patients achieve nutritional autonomy with dietary modification (eg, hyperphagia, small frequent meals, and oral rehydration fluids), those with moderate-to-severe disease may develop SBS-IF and become dependent on parenteral support (PS) in the form of intravenous fluids and/or nutrition for sustenance of life. SBS-IF is a chronic debilitating disease associated with a poor quality of life, and carries significant morbidity and health care costs. Medical management of SBS-IF is primarily focused on individually tailored symptomatic treatment strategies, such as antisecretory and antidiarrheal agents to mitigate fluid losses, and PS. However, PS administration is associated with potentially life-threatening complications, such as central venous thromboses, bloodstream infections, and liver disease. In pursuit of a targeted therapy to augment intestinal adaptation, research over the past 2 decades has identified glucagon-like peptide, an intestinotrophic gut peptide that has been shown to enhance intestinal absorptive capacity by causing an increase in the villus length, crypt depth, and mesenteric blood flow and by decreasing gastrointestinal motility and secretions. Teduglutide, a recombinant analog of glucagon-like peptide-2, is the first targeted therapeutic agent to gain approval for use in adult SBS-IF. Teduglutide was shown to result in significant (20%-100%) reduction in PS-volume requirement and have a satisfactory safety profile in three randomized control trials. Further research is warranted to see if reduction in PS dependency translates to improved quality of life and reduced PS-associated complications.
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PMID:Targeted therapy of short-bowel syndrome with teduglutide: the new kid on the block. 2552 80

Enteroendocrine L cells and glucagon-like peptide 2 (GLP-2) secretion are activated in the intestinal adaptation process following bowel resection in patients with short bowel syndrome. We hypothesized that enteral activation of Takeda G protein-coupled receptor 5 (TGR5), expressed in enteroendocrine L cells, could augment endogenous GLP-2 secretion and the intestinal adaptation response. Our aim was to assess the efficacy of different TGR5 agonists to stimulate GLP-2 secretion and intestinal adaptation in a piglet short-bowel model. In study 1, parenterally fed neonatal pigs (n = 6/group) were gavaged with vehicle, olive extract (OE; 10 or 50 mg/kg), or ursolic acid (UA; 10 mg/kg), and plasma GLP-2 was measured for 6 h. In study 2, neonatal pigs (n = 6-8/group) were subjected to transection or 80% mid-small intestine resection and, after 2 days, assigned to treatments for 10 days as follows: 1) transection + vehicle (sham), 2) resection + vehicle (SBS), 3) resection + 30 mg UA (SBS + UA), and 4) resection + 180 mg/kg OE (SBS + OE). We measured plasma GLP-2, intestinal histology, cell proliferation, and gene expression, as well as whole body citrulline-arginine kinetics and bile acid profiles. In study 1, GLP-2 secretion was increased by UA and tended to be increased by OE. In study 2, SBS alone, but not additional treatment with either TGR5 agonist, resulted in increased mucosal thickness and crypt cell proliferation in remnant jejunum and ileum sections. SBS increased biliary and ileal concentration of bile acids and expression of inflammatory and farnesoid X receptor target genes, but these measures were suppressed by UA treatment. In conclusion, UA is an effective oral GLP-2 secretagogue in parenterally fed pigs but is not capable of augmenting GLP-2 secretion or the intestinal adaptation response after massive small bowel resection. NEW & NOTEWORTHY Therapeutic activation of endogenous glucagon-like peptide 2 (GLP-2) secretion is a promising strategy to improve intestinal adaptation in patients with short bowel syndrome. This study in neonatal pigs showed that oral supplementation with a selective Takeda G protein-coupled receptor 5 (TGR5) agonist is an effective approach to increase GLP-2 secretion. The results warrant further study to establish a more potent oral TGR5 agonist that can effectively improve intestinal adaptation in pediatric patients with SBS.
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PMID:Differential action of TGR5 agonists on GLP-2 secretion and promotion of intestinal adaptation in a piglet short bowel model. 3092 Mar 8

Teduglutide (TED) reduces the need for parenteral support (PS) in patients with short-bowel syndrome with intestinal failure (SBS-IF). It is a glucagon-like peptide-2 analog that improves absorption, induces the expansion of the absorptive epithelium in the small intestine, and may be used in patients with SBS-IF after a 6- to 12-month adaptation period, if PS is always necessary. We described the functional and morphological effect of TED in a 40-year-old female patient with SBS-IF due to Crohn's disease who underwent terminal jejunostomy after 12 months of drug exposition. Marked hypertrophy of the villi was detected by endoscopic capsule and confirmed by histological measurements. This is the first publication demonstrating an increase in intestinal absorption in an SBS-IF patient treated with TED because of a morphological adaptation of the small bowel, with hyperplasia confirmed by capsule endoscopy and histology. The capsule endoscopy, a noninvasive exploration of the gut, could be evaluated to monitor the real efficacy of treatments with growth factors in SBS patients.
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PMID:Small-Bowel Adaptation: A Case of Morphological Changes Induced by Teduglutide in Short-Bowel Syndrome With Intestinal Failure. 3218 83