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Query: UMLS:C0011849 (diabetes)
 277,896 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Functioning gastroenteropancreatic endocrine tumors produce and secrete different substances that can be detected in the plasma and cause hormone-related syndromes. Symptoms such as diarrhea associated either with typical skin rash or peptic ulcer disease may be suggestive of the presence of intestinal carcinoid or gastrinoma. Other clinical manifestations such as severe hypoglycemia, diabetes, necrolytic erythema and gallbladder disease may also indicate an endocrine tumor. Sometimes, patients present no, or just vague, symptoms such as dyspepsia or abdominal pain and nonfunctioning endocrine tumors in these patients can be found incidentally during diagnostic imaging procedures or at operation. Usually, the diagnosis is established by the measurement of the specific tumor marker in the plasma and, sometimes, in the urine. In some cases, normal basal hormone levels are observed even in the presence of typical symptoms. Therefore, stimulatory tests such as the secretin test for gastrinomas are required to establish the diagnosis. General markers for the diagnosis of gastroenteropancreatic endocrine tumors are also available. Among these, chromogranin A has proved to be of great value for diagnosing nonfunctioning tumors and is considered the most sensitive general marker. The availability of both specific and general markers as well as stimulatory tests may enable the clinician to diagnose functioning gastroenteropancreatic endocrine tumors at an early stage and to recognize nonfunctioning tumors.
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PMID:Biochemical diagnosis of gastroenteropancreatic endocrine tumors. 1271 97

Glucagonoma of the pancreas is a rare tumor with distinct clinical manifestations, such as necrolytic migratory erythema,weight loss, anemia, diabetes mellitus, and hypoamino-acidemia. We report the case of a 68-year-old Japanese man who underwent curative resection for malignant glucagonoma of the pancreas diagnosed through anemia and diabetes mellitus. The patient had had diabetes mellitus for 20 years. Anemia was diagnosed in 1998. On admission, the hemoglobin level was 8.3g/dl, but the levels of serum iron, vitamin B12, and erythropoietin and, the number of reticulocytes were within normal limits. The levels of carcinoembryonic antigen (CEA), carbohydrate antigen (CA)19-9, and DUPAN-2 were also within normal limits, and exocrine function of the pancreas (PFD, 75%) was normal. Ultrasonography (US) revealed a hypoechoic tumor in the distal pancreas. Computed tomography (CT) demonstrated a high-density area 4 cm in diameter with calcification. The serum glucagon level was very high (2360 pg/ml), but the levels of other hormones such as somatostatin or gastrin were within normal limits, while insulin was low. Glucagonoma of the pancreas was diagnosed, and distal pancreatectomy with splenectomy was performed. Histological examination revealed a malignant endocrine tumor,which was immunohistochemically positive for chromogranin A and glucagon. Two months after the operation, the serum glucagon level had decreased to within normal limits and the hemoglobin level had increased to 10.4 g/dl. The case of glucagonoma reported here was found through diagnostic examinations of anemia and treated by surgical resection, by which the patient's anemia was largely alleviated. Therefore, we recommend checking patients who have diabetes mellitus and anemia in order to diagnose and treat glucagonoma in its early stage.
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PMID:Malignant glucagonoma of the pancreas diagnoses through anemia and diabetes mellitus. 1291 65

We report a potential pitfall of 123I-metaiodobenzylguanine (MIBG) scan. Magnetic resonance imaging performed for other reasons, showed 2.5 cm tumor in the left adrenal gland. On questioning patient had episodic palpitations, flushing and hypertension suggestive of pheochromocytoma. Urinary metanephrine level was of borderline value but serum chromogranin A level was clearly elevated. 123I-MIBG scan showed accumulation of the tracer in the upper left abdomen and the finding was suspected to be intra-adrenal pheochromocytoma. During operation two separate tumors, adrenocortical adenoma in the left adrenal gland, and another smaller, extra-adrenal paraganglioma locating very close to the adenoma, were found. Thus the positive MIBG finding was caused by a paraganglioma with the concurrent presentation of nonfunctioning adrenocortical adenoma.
Exp Clin Endocrinol Diabetes 2003 Aug
PMID:A pitfall of metaiodobenzylguanidine scan: paraganglioma in close proximity to adrenocortical adenoma. 1295 37

The rat insulinoma cell line RINm5F, an insulin secreting pancreatic beta cell line, has been used as an attractive model for basic studies of the mechanisms of insulin secretion and, more recently, as a model for the development of alternative methods for the treatment of diabetes. To elucidate the cytological properties and expression patterns of hormones of the gastro-entero-pancreatic system, suspensions of RINm5F cells were investigated by various methods including immunocytochemistry on serial semithin sections, quantitative immunocytochemistry, routine electron microscopy, immuno-electron microscopy, in situ hybridization, and TUNEL technique. At the ultrastructural level, several phenotypes of RIm5F cells were characterized by differences in the number, shape, size, and density of their secretory granules. The most common type contained a mixture of round granules varying in size and electron density. A second type predominantly contained relatively large, moderately dense granules. Moreover, a minority of cells was characterized by the occurrence of polymorphous electron dense granules or the complete absence of any secretory granules. The immunohistochemical data showed that, among the established islet hormones, insulin was present in more than 50% of cells, whereas glucagon and somatostatin occurred only sporadically. Though cells positive for pancreatic polypeptide (PP) were not found, PP-related peptides (NPY and PYY) however could be detected in a minority of cells. The great majority of RINm5F cells were immunoreactive for chromogranin B (CgB), followed by insulin, chromogranin A (CgA), and serotonin (5-HT). In addition to intercellular differences in the density of immunostaining, numerous colocalizations of immunoreactivities were found, suggesting that RINm5F cells represent a mixture of subtypes concerning the individual pattern of hormone expression. The present results reveal a wide range of heterogeneity with respect to the morphology and especially the hormone content between individual RINm5F cells.
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PMID:Cytological and immunocytochemical characterization of the insulin secreting insulinoma cell line RINm5F. 1512 25

Chromogranins or secretogranins (granins), present in secretory granules of virtually all neuroendocrine cells and neurones, are structurally related proteins encoded by different genetic loci: chromogranins A and B, and secretogranins II through VI. Compelling evidence supports both intracellular and extracellular functions for this protein family. Within the cells of origin, a granulogenic or sorting role in the regulated pathway of hormone or neurotransmitter secretion has been documented, especially for chromogranin A (CHGA). Granins also function as pro-hormones, giving rise by proteolytic processing to an array of peptide fragments for which diverse autocrine, paracrine, and endocrine activities have been demonstrated. CHGA measurements yield insight into the pathogenesis of such human diseases as essential hypertension, in which deficiency of the catecholamine release-inhibitory CHGA fragment catestatin may trigger sympathoadrenal overactivity as an aetiologic culprit in the syndrome. The CHGA dysglycaemic fragment pancreastatin is functional in humans in vivo, affecting both carbohydrate (glucose) and lipid (fatty acid) metabolism. Pancreastatin is cleaved from CHGA in hormone storage granules in vivo, and its plasma concentration varies in human disease. The pancreastatin region of CHGA gives rise to three naturally occurring human variants, one of which (Gly297Ser) occurs in the functionally important carboxy-terminus of the peptide, and substantially increases the peptide's potency to inhibit cellular glucose uptake. These observations establish a role for pancreastatin in human intermediary metabolism and disease, and suggest that qualitative hereditary alterations in pancreastatin's primary structure may give rise to interindividual differences in glucose disposition.
Diabetes Obes Metab 2006 Nov
PMID:Catecholamine storage vesicles and the metabolic syndrome: The role of the chromogranin A fragment pancreastatin. 1702 86

Type 1 diabetes is resulting from the selective destruction of insulin-producing betacells within the pancreatic islets. Somatostatin acts as an inhibitor of hormone secretion through specific receptors (sst1-5). All ssts were expressed in normal rat and mouse pancreatic islets, although the expression intensity and the co-expression pattern varied between ssts as well as between species. This may reflect a difference in response to somatostatin in islet cells of the two species. The Non-Obese Diabetic (NOD) mouse model is an experimental model of type 1 diabetes, with insulitis accompanied by spontaneous hyperglycaemia. Pancreatic specimens from NOD mice at different age and stage of disease were stained for ssts. The islet cells of diabetic NOD mice showed increased islet expression of sst2-5 compared to normoglycemic NOD mice. The increase in sst2-5 expression in the islets cells may suggest either a contributing factor in the process leading to diabetes, or a defense response against ongoing beta-cell destruction. Somatostatin analogues were tested on a human endocrine pancreatic tumour cell line and cultured pancreatic islets. Somatostatin analogues had an effect on cAMP accumulation, chromogranin A secretion and MAP kinase activity in the cell line. Treatment of rat pancreatic islets with somatostatin analogues with selective receptor affinity was not sufficient to induce an inhibition of insulin and glucagon secretion. However, a combination of selective analogues or non-selective analogues via costimulation of receptors can cause inhibition of hormone production. For insulin and glucagon, combinations of sst2 + sst5 and sst1 + sst2, respectively, showed a biological effect. In summary, knowledge of islet cell ssts expression and the effect of somatostatin analogues with high affinity to ssts may be valuable in the future attempts to influence beta-cell function in type 1 diabetes mellitus, since down-regulation of beta-cell function may promote survival of these cells during the autoimmune attack.
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PMID:Somatostatin receptor expression and biological functions in endocrine pancreatic cells: review based on a doctoral thesis. 1757 4

Type 1 diabetes is usually associated with other autoimmune diseases. Parietal cell antibodies (PCA) are found in 20% of type 1 diabetic patients which might be an early sign of autoimmune gastritis and pernicious anemia. PCA destroy the gastric H+/K+ ATP-ase. The chronic auto-destruction of the proton pump leads to hypo/achlorhydria and hypergastrinemia which leads to the hyper/dysplasia of enterochromaffin-like cells (ECL). ECL hyper/dysplasia is known to increase the likelihood of gastric carcinoid tumor development in affected patients. Gastric carcinoid tumors forming from the hyperplasia of ECL cells are found in 4-9% of patients having autoimmune gastritis or pernicious anemia. The 29-years-old type 1 diabetic patient, having primer hyperthyroidism was admitted to our clinic because of gastric pain. Results of endoscopy and biopsy showed multiple small polyps in the fundus with non-antral hypergastrinemic (type A) atrophic gastritis. The parietal cell antibody test was positive, the serum chromogranin A level was 289,7 ng/ml (normal value $ 98 ng/ml), TSH level was 9,93 mIU/L. The histological examination indicated carcinoid tumor. Sandostatin therapy was started then partial gastrectomy was done. After the operation the plasma chromogranin level normalized. Non-antral, multiple polyps could cover silent neuroendocrine tumors, which are slowly growing benign endocrine tumors, however, they also might be high malignity endocrine carcinomas. These tumors could be easily recognized in the clinical practice by measuring the serum or tissue chromogranin A level and other markers of tumor growth. Thus screening of gastric endocrine tumors in type 1 diabetic patients with co-morbid autoimmune diseases is recommended.
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PMID:[Development of silent gastric carcinoid in a type 1 diabetic patient with primer hypothyreosis]. 1772 Jun 74

In the present review, we discuss the sorting mechanism of peptide hormones and the biogenesis mechanism of secretory granules in view of the significance of the high cholesterol composition of secretory granule membranes. Peptide hormones and granin-family proteins are sorted to immature budding granules at the trans-Golgi network in neuroendocrine cells. Two models have been proposed for granule protein sorting: "aggregation-mediated sorting" and "receptor-mediated sorting". In the aggregation-mediated sorting model, granin-family proteins such as chromogranin A and B form aggregates with peptide hormones in weakly acidic, high calcium milieu of the budding granules. Chromogranins have a disulfide loop at their N-terminal at which they bind to the budding granular membrane, and bring hormones to the granules. In the receptor-mediated sorting model, carboxypeptidase E and/or secretogranin III function as a sorting receptor for peptide hormones. They bind peptide hormones, such as proopiomelanocortin, and have a high-cholesterol-binding domain. Since secretory granule membranes contain high levels of cholesterol, peptide hormones are brought to the secretory granules by these receptors. Although the two models have been conflicting, we suggest that both are cooperative and compensating each other for the sorting of peptide hormones and the biogenesis of secretory granules.
Curr Diabetes Rev 2008 Feb
PMID:Sorting mechanism of peptide hormones and biogenesis mechanism of secretory granules by secretogranin III, a cholesterol-binding protein, in endocrine cells. 1822 Jun 93

We report a case of recurrent hypoglycemia due to malignant insulinoma in a type 2 diabetic patient correctly controlled for years with the same doses of oral antidiabetic agents. A 79-year-old woman was admitted for recurrent severe hypoglycemia. She had a history of type 2 diabetes since 2000. HbA1c was 7.8% when she reported mild hypoglycemia and 5.8% when recurrent hypoglycemia appeared despite progressive diminution of glicazide. Severe hypoglycemia continued despite interrupting diabetes medications. At admission, results showed inappropriately elevated insulin, C-peptide and proinsulin levels despite significant hypoglycemia. CT scan showed "cystic" nodes in the pancreas and in the liver. Liver biopsy found a well-differentiated neuroendocrine carcinoma with positive staining for chromogranin A and negative staining for insulin. Hypoglycemia improved with diazoxide, lanreotide and dextrose infusion. Liver chemoembolization was planned. Severe edema, dyspnea, hyponatremia, and hypo-osmolarity occurred. The patient's clinical status deteriorated rapidly with severe cardiac, renal and hepatic failure. She died in a few days. Association of diabetes mellitus and insulinoma is extremely rare. Malignant insulinoma survival is less than two years, shorter when hepatic localizations are present at diagnosis. Association of diabetes with insulinoma delays the diagnosis, but does not alter prognosis or favor carcinoma frequency. Lanreotide was inefficient in our patient despite good responses described in the literature. Heart, respiratory and renal failures have been described with diazoxide independently of the doses; this may in part explain the rapid death. Insulinoma should be considered as a cause of unusual and recurrent hypoglycemia in a diabetic patient especially if it persists after interrupting antidiabetic agents.
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PMID:Association of malignant insulinoma and type 2 diabetes mellitus: a case report. 1829 48

Numerous studies conducted in a diversity of adult tissues have shown that certain stem cells are characterized by the expression of a protein known as the ABCG2 transporter (where ABC is ATP- binding cassette). In the adult pancreas, although various multipotent progenitors have been proposed, the ABCG2 marker has only been detected in the so-called 'side population' (a primitive haematopoietic cell population with a multipotential capacity). In the present study we sought to identify new ABCG2+ pancreatic cell populations and to explore whether they exhibit the properties of progenitor cells. We isolated and expanded mitoxantrone-resistant cells from pancreata of lactating rats by drug selection. These cells were characterized and maintained in different stages of differentiation using several media 'cocktails' plus Matrigel (BD Biosciences). Differentiation was assessed by RT-PCR (reverse transcription-PCR), immunocytochemistry, electron microscopy and ELISA. The expanded cell population demonstrated a phenotype of PaSCs (pancreatic stellate cells). Spontaneous cell clusters occurred during cell expansion and they showed weak expression of the transcription factor Pdx1 (pancreatic and duodenal homeobox 1). Moreover, the presence of inductive factors in the Matrigel plus exendin-4 led to an increase in Pdx1 and endocrine genes, such as insulin, islet amyloid polypeptide, glucagon, the glucose transporter GLUT2, chromogranin A and the convertases PC1/3 and PC2 were also detected. Immunocytochemical analysis showed co-localization of insulin and C-peptide, whereas ultrastructural studies revealed the presence of granules. Insulin secretion from cell clusters was detected in the cell culture medium. We identified a population of PaSCs that express the ABCG2+ transporter and have the capacity to transdifferentiate into insulin-producing cells. Although the potential therapeutic application remains to be tested, PaSCs could represent a future option for insulin replacement in diabetes research.
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PMID:Identification of a pancreatic stellate cell population with properties of progenitor cells: new role for stellate cells in the pancreas. 1955 23


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