Fasting ghrelin but not PYY(3-36) is associated with insulin-resistance independently of body weight in Wistar rats / A grelina, mas não PYY(3-36), está associada com a resistência à insulina independente do peso corporal em ratos Wistar

Objective: The objective of this study was to evaluate the association between insulin-resistance and fasting levels of ghrelin and PYY in Wistar rats. Materials and methods: A total of 25 male Wistar rats, weighing 200-300 g, was included in this study. The animals were maintained in cages with a 12/12h light-dark cycle and fed standard chow and water ad libitum. After 12-h overnight fasting, ghrelin, PYY, insulin and glucose values were determined. Insulin resistance was assessed by means of the HOMA-IR, which was ranked and the median was used as a cut-off value to categorize insulin-resistance. HOMA-IR values equal and above 2.62 were considered insulin-resistant (IR) while values below 2.62 were considered insulin sensitive (IS). Differences between means were determined using the Student t-test. Multiple regression and Pearson’s correlation test were used to evaluate the association between variables. Results: HOMA-IR median IQ range values for IS and IR groups were, respectively, 1.56 (0.89 – 2.16) vs. [4.06 (3.50 – 4.61); p < 0.001]. The IR group presented increased levels of fasting ghrelin, PYY and insulin respectively: [50.35 (25.99 – 74.71) pg/mL vs. 12.33 (8.77 – 15.89) pg/mL; p = 0.001]; [54.38 (37.50 – 71.26) pg/mL vs. 33.17 (22.34 – 43.99) pg/mL; p = 0.016]; [18.04 (14.48 – 21.60) uU/mL vs. 7.09 (4.83 – 9.35) uU/mL; p = 0.001]. Ghrelin, but not PYY, correlated linearly and positively with HOMA-IR: ghrelin vs. HOMA-IR (r = 0.52; p = 0.008), and PYY vs. HOMA-IR (r = 0.22; p = 0.200). This correlation was independent of body weight. Conclusion: Fasting ghrelin and PYY serum levels are increased in lean, relatively insulin resistant Wistar rats, and this increase is independent of weight. .

Objetivo: O objetivo deste estudo foi avaliar a associação entre a resistência à insulina e os níveis de grelina e PYY em jejum em ratos Wistar. Materiais e métodos: Um total de 25 ratos Wistar machos, pesando 200-300 g, foi usado neste estudo. Os animais foram mantidos em gaiolas com um ciclo de luz escuro de 12/12h e alimentados com ração padrão e água ad libitum. Depois de um jejum de 12h, os valores de grelina, PYY, insulina e glicose foram determinados. A resistência à insulina foi avaliada pelo HOMA-IR que foi ordenado e a mediana utilizada como valor de corte para categorizar a resistência à insulina. Os valores de HOMA-IR iguais ou acima de 2,62 foram considerados resistentes à insulina (RI), enquanto valores abaixo de 2,62 foram considerados sensíveis (SI). As diferenças entre as médias foram determinadas usando-se o teste t de Student. A análise de regressões múltiplas e o teste de correlação de Pearson foram usados para se avaliar a associação entre as variáveis. Resultados: A mediana e a variação IQ do HOMA-IR para os grupos RI e SI foram, respectivamente, 1,56 (0,89 – 2,16) contra [4,06 (3,50 – 4,61); p < 0,001]. O grupo RI apresentou níveis aumentados de grelina, PYY e insulina em jejum, respectivamente, [50,35 (25,99 – 74,71) pg/mL contra 12,33 (8,77 – 15,89) pg/mL; p = 0,001]; [54,38 (37,50 – 71,26) pg/mL contra 33,17 (22,34 – 43,99) pg/mL; p = 0,016]; [18,04 (14,48 – 21,60) uU/mL contra 7,09 (4,83 – 9,35) uU/mL; p = 0.001]. A grelina, mas não PYY, se correlacionou de forma linear e positiva com o HOMA-IR: a grelina contra HOMA-IR (r = 0,52; p = 0,008), e PYY contra HOMA-IR (r = 0,22; p = 0,200). Essa correlação foi independente do peso corporal. Conclusão: Os níveis séricos de jejum de grelina ...

Metabolic effects of an entero-omentectomy in mildly obese type 2 diabetes mellitus patients after three years

BACKGROUND: Various digestive tract procedures effectively improve metabolic syndrome, especially the control of type 2 diabetes mellitus. Very good metabolic results have been shown with vertical gastrectomy and entero-omentectomy; however, the metabolic effects of an isolated entero-omentectomy have not been previously studied. METHODS: Nine patients with type 2 diabetes mellitus and a body mass index ranging from 29 to 34.8 kg/m² underwent an entero-omentectomy procedure that consisted of an enterectomy of the middle jejunum and exeresis of the major part of the omentum performed through a mini-laparotomy. Glucagon-like peptide-1 and peptide YY were measured preoperatively and three months following the operation. Fasting and postprandial variations in glycemia, insulinemia, triglyceridemia, hemoglobin A1c, and body mass index were determined in the preoperative period and 3, 18 and, 36 months after the operation. RESULTS: All patients significantly improved the control of their type 2 diabetes mellitus. Postprandial secretion of peptide YY and Glucagon-like peptide-1 were enhanced, whereas hemoglobin A1c, fasting and postprandial glucose, insulin, and triglyceride levels were significantly reduced. Mean body mass index was reduced from 31.1 to 27.3 kg/m². No major surgical or nutritional complications occurred. CONCLUSIONS: Entero-omentectomy is easy and safe to perform. A simple reduction in jejunal extension and visceral fat causes important improvements in the metabolic profile.

Increased Immunoendocrine Cells in Intestinal Mucosa of Postinfectious Irritable Bowel Syndrome Patients 3 Years after Acute Shigella Infection: An Observation in a Small Case Control Study

PURPOSE: Postinfectiously irritable bowel syndrome (PI-IBS) develops in 3-30% of individuals with bacterial gastroenteritis. Recent studies demonstrated increases in inflammatory components in gut mucosa of PI-IBS patients even after complete resolution of infection. We aimed to investigate histological changes in colon and rectum of PI-IBS subjects after long term period of infection. MATERIALS AND METHODS: We recruited PI-IBS subjects who had been diagnosed IBS after complete resolution of enteritis caused by shigellosis outbreak 3 years earlier. We compared unmatched four groups, PI-IBS (n = 4), non PI-IBS (n = 7), D-IBS (n = 7, diarrhea predominant type) and healthy controls (n = 10). All of them underwent colonoscopic biopsy at three areas, including descending colon (DC), sigmoid colon (SC) and rectum, which were assessed for 5-hydroxytryptamine (5-HT)/peptide YY (PYY)-containing enterochromaffin (EC) cell, intraepithelial (IEL) and lamina propria T lymphocyte (CD3), CD8 lymphocytes, mast cells and CD68/calprotectin+ macrophages. RESULTS: All subjects had no structural or gross abnormalities at colonoscopy. In PI-IBS, 5-HT containing EC cells, PYY containing EC cells, IELs, CD3 lymphocytes, CD8 lymphocytes, mast cells, and CD68 + macrophages were increased compared to control (p < 0.05). In D-IBS, PYY containing EC cells, IELs, and CD3 lymphocytes were increased compared to control (p < 0.05). In PI-IBS, 5-HT containing EC cells tended to increase and PYY containing EC cells, CD8 lymphocytes, mast cells, and CD68+ macrophages were increased compared to non PI-IBS (p < 0.05). Calprotectin + marcrophages were decreased in PI-IBS, non PI-IBS and IBS compared to control. CONCLUSION: The immunoendocrine cells were sporadically increased in PI-IBS, non PI-IBS and D-IBS compared with control. Our findings in a very small number of patients suggest that mucosal inflammation may play a role in long-term PI-IBS, and that other sub-groups of IBS and larger scale studies are needed to confirm this observation.

Immunocytochemical study of the distribuition of endocrine cells in the pancreas of the Brazilian sparrow species Zonotrichia Capensis Subtorquata (Swaison, 1837)

In the present study, we investigated types of pancreatic endocrine cells and its respective peptides in the Brazilian sparrow species using immunocytochemistry. The use of polyclonal specific antisera for somatostatin, glucagon, avian pancreatic polypeptide (APP), YY polypeptide (PYY) and insulin, revealed a diversified distribution in the pancreas. All these types of immunoreactive cells were observed in the pancreas with different amounts. Insulin- Immunoreactive cells to (B cells) were most numerous, preferably occupying the central place in the pancreatic islets. Somatostatin, PPA, PYY and glucagon immunoreactive cells occurred in a lower frequency in the periphery of pancreatic islets.

Os tipos de células endócrinas e seus respectivos peptídeos reguladores foram estudados imunocitoquimicamente no pâncreas do tico-tico, espécie Zonotrichia capensis subtorquata, empregando-se o método imunocitoquímico ABC - Peroxidase (Complexo Avidina - Biotina - Peroxidase) e anti-soros específicos para somatostatina, ao glucagon, ao polipeptídeo pancreático aviário (PPA), ao polipeptídeo YY (PYY) e à insulina. Todos estes tipos de células imunorreativas foram observadas no pâncreas em quantidades diferentes. As células imunorreativas à insulina (células B) foram as mais numerosas, ocupando preferencialmente, a região central das ilhotas pancreáticas. As células endócrinas imunorreativas à somatostatina, PPA, PYY e glucagon localizaram-se predominantemente na periferia das ilhotas.