peptide-yy and Hypoglycemia

Roux-en-Y gastric bypass (RYGB) augments postprandial secretion of glucagon-like peptide 1 (GLP-1), oxyntomodulin (OXM), and peptide YY (PYY). Subcutaneous infusion of these hormones ("GOP"), mimicking postprandial levels, reduces energy intake. Our objective was to study the effects of GOP on glycemia and body weight when given for 4 weeks to patients with diabetes and obesity.. In this single-blinded mechanistic study, obese patients with prediabetes/diabetes were randomized to GOP (. GOP infusion improves glycemia and reduces body weight. It achieves superior glucose tolerance and reduced glucose variability compared with RYGB and VLCD. GOP is a viable alternative for the treatment of diabetes with favorable effects on body weight.

Topics: Adult; Blood Glucose; Blood Glucose Self-Monitoring; Body Weight; Diabetes Mellitus, Type 2; Drug Therapy, Combination; Female; Glucagon-Like Peptide 1; Humans; Hypoglycemia; Infusions, Subcutaneous; Insulin; Male; Meals; Middle Aged; Obesity; Oxyntomodulin; Peptide YY; Postprandial Period; Prediabetic State; Single-Blind Method; Weight Loss

Dumping syndrome (DS) and postbariatric hypoglycemia (PBH) are frequent complications of bariatric surgery. Previously known as "early and late dumping," these complications have been separated due to differences in their onset and behaviors.. To investigate a potentially common etiology of DS and PBH using an analysis of a mixed meal test (MMT) study.. A large teaching hospital in the Netherlands.. From all patients who underwent bariatric surgery in 2008-2011, a random selection completed an MMT (n = 47). Patients scored complaints related to DS and PBH with a standardized questionnaire at several time intervals. The groups were divided into patients with (DS+; n = 22) and without (DS-; n = 25) an increase in DS symptoms after the start of the MMT. Glucose and gut hormone levels were compared. Hypoglycemia was defined as a blood glucose level below 3.3 mmol/L.. The DS+ group had lower blood glucose values compared to the DS- group, which reached significance at 90 and 120 minutes (P < .05). For the DS+ group, glucagon-like peptide-1 (GLP-1), peptide YY (PYY), and satiety were higher at various time intervals (P < .05) compared to the DS- group. No differences were found for insulin and hunger score. GLP-1 and PYY were correlated with symptoms of DS.. Patients with DS complaints had lower postprandial glucose values. GLP-1 and PYY values were elevated in the DS+ group early and late during the test. These hormones also correlated with DS. These findings support the hypothesis of a common etiology of DS and PBH and a role of GLP-1 and PYY in both complications.

Topics: Bariatric Surgery; Blood Glucose; Dumping Syndrome; Gastric Bypass; Humans; Hypoglycemia; Obesity, Morbid; Peptide YY

Altered enteroendocrine hormone responses are widely believed to underlie the beneficial effects of bariatric surgery in type 2 diabetes. While elevated postprandial glucagon-like peptide-1 (GLP-1) is considered one of the mediators, increased postprandial glucagon levels have recently been implicated.. We investigated hormonal responses in lean patients after prophylactic total gastrectomy (PTG), as a model of Roux-en-Y gastric bypass without the confounding effects of obesity or massive weight loss.. University hospital, United Kingdom.. PTG participants exhibited accelerated plasma glucose appearance, followed, in 3 of 10 cases, by hypoglycemia (<3 mM glucose). Plasma GLP-1, peptide YY, glucose-dependent insulinotropic-polypeptide, glicentin, and oxyntomodulin responses were elevated, and glucagon appeared to rise in PTG participants when measured with a glucagon-specific enzyme-linked immunosorbent assay. We revisited the specificity of this assay, and demonstrated significant cross-reactivity with glicentin and oxyntomodulin at concentrations observed in PTG plasma. Reassessment of glucagon with the same assay using a modified protocol, and by liquid chromatography-mass spectrometry, demonstrated suppression of glucagon secretion after oral glucose tolerance tests in both PTG and control cohorts.. Care should be taken when assessing glucagon levels in the presence of elevated plasma levels of other proglucagon products. Substantial elevation of GLP-1 and insulin responses after PTG likely contribute to the observed hypoglycemia, and mirror similar hormone levels and complications observed in bariatric weight loss patients.

Topics: Adult; Bariatric Surgery; Blood Glucose; Case-Control Studies; Female; Gastrectomy; Gastric Bypass; Gastric Inhibitory Polypeptide; Glucagon; Glucagon-Like Peptide 1; Glucose Tolerance Test; Humans; Hypoglycemia; Insulin; Male; Peptide YY; Proglucagon; Thinness

Peptide YY (PYY), neuropeptide Y, and pancreatic polypeptide (PP) are the third family of structurally related peptides to be extracted from the brain-gut axis. In the present study we have validated a sensitive and specific assay for PYY and used it to measure the distribution of PYY in the canine gastrointestinal tract. In addition we have compared the PYY and PP responses to both an intragastric meal and to insulin hypoglycemia. The highest concentration of PYY was present in the canine ileum (1610 +/- 123 ng/g) and colon (1607 +/- 194 ng/g). Significant (p less than 0.05) increases in both circulating PP and PYY concentrations were observed in response to the meal (mean delta PP = 180 +/- 43 pg/ml; mean delta PYY = 205 +/- 61 pg/ml). In contrast, only serum PP concentrations (mean delta PP = 294 +/- 36 pg/ml) increased significantly (p less than 0.01) in response to insulin hypoglycemia, demonstrating differences in the sensitivity of the PP and PYY cells to vagal stimulation. The present demonstration of PYY release in response to a physiological stimulus fulfills one of the prerequisites for hormonal status.

Topics: Amino Acid Sequence; Animals; Chromatography; Colon; Digestive System; Dogs; Eating; Gastrointestinal Hormones; Hypoglycemia; Ileum; Nerve Tissue Proteins; Neuropeptide Y; Pancreatic Polypeptide; Peptide YY; Peptides; Radioimmunoassay