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International Journal of Molecular... Jul 2019Hundred years after the discovery of glucagon, its biology remains enigmatic. Accurate measurement of glucagon has been essential for uncovering its pathological... (Review)
Review
Hundred years after the discovery of glucagon, its biology remains enigmatic. Accurate measurement of glucagon has been essential for uncovering its pathological hypersecretion that underlies various metabolic diseases including not only diabetes and liver diseases but also cancers (glucagonomas). The suggested key role of glucagon in the development of diabetes has been termed the bihormonal hypothesis. However, studying tissue-specific knockout of the glucagon receptor has revealed that the physiological role of glucagon may extend beyond blood-glucose regulation. Decades ago, animal and human studies reported an important role of glucagon in amino acid metabolism through ureagenesis. Using modern technologies such as metabolomic profiling, knowledge about the effects of glucagon on amino acid metabolism has been expanded and the mechanisms involved further delineated. Glucagon receptor antagonists have indirectly put focus on glucagon's potential role in lipid metabolism, as individuals treated with these antagonists showed dyslipidemia and increased hepatic fat. One emerging field in glucagon biology now seems to include the concept of hepatic glucagon resistance. Here, we discuss the roles of glucagon in glucose homeostasis, amino acid metabolism, and lipid metabolism and present speculations on the molecular pathways causing and associating with postulated hepatic glucagon resistance.
Topics: Amino Acids; Animals; Biomarkers; Glucagon; Humans; Lipid Metabolism; Receptors, Glucagon; Signal Transduction
PubMed: 31284506
DOI: 10.3390/ijms20133314 -
Journal of Neuroendocrinology Aug 2023This ENETS guidance paper aims to provide practical advice to clinicians for the diagnosis, treatment and follow-up of functioning syndromes in pancreatic neuroendocrine...
This ENETS guidance paper aims to provide practical advice to clinicians for the diagnosis, treatment and follow-up of functioning syndromes in pancreatic neuroendocrine tumours (NET). A NET-associated functioning syndrome is defined by the presence of a clinical syndrome combined with biochemical evidence of inappropriately elevated hormonal levels. Different hormonal syndromes can be encountered in pancreatic NET patients, including insulinoma, gastrinoma as well as the rare glucagonoma, VIPoma, ACTHoma, PTHrPoma, carcinoid syndrome, calcitoninoma, GHRHoma and somatostatinoma. The recommendations provided in this paper focus on the biochemical, genetic and imaging work-up as well as therapeutic management of the individual hormonal syndromes in well-differentiated, grade 1-3, functioning NET with the primary tumour originating in the pancreas, and for specific subtypes also in the duodenum.
Topics: Humans; Neuroendocrine Tumors; Pancreatic Neoplasms; Insulinoma; Gastrinoma; Glucagonoma
PubMed: 37578384
DOI: 10.1111/jne.13318 -
International Journal of Molecular... Aug 2023Secondary diabetes mellitus is frequently ignored in specialized literature. In this narrative review, the main endocrinopathies accompanied by increased glycemic values... (Review)
Review
Secondary diabetes mellitus is frequently ignored in specialized literature. In this narrative review, the main endocrinopathies accompanied by increased glycemic values are identified, as well as the mechanisms by which the excess or deficiency of certain hormones impact beta cell function or insulin resistance. The main endocrinopathies (acromegaly, Cushing's syndrome, Basedow-Graves' disease, pheochromocytoma, somatostatinoma and glucagonoma) and their characteristics are described along with the impact of hormone changes on blood sugar, body mass index and other parameters associated with diabetes. The overall information regarding the complex molecular mechanisms that cause the risk of secondary diabetes and metabolic syndrome is of crucial importance in order to prevent the development of the disease and its complications and particularly to reduce the cardiovascular risk of these patients. The purpose of this study is to highlight the particular features of endocrine pathologies accompanied by an increased risk of developing diabetes, in the context of personalized therapeutic decision making. The epidemiological, physiopathological, clinical and therapeutic approaches are presented along with the importance of screening for diabetes in endocrine diseases.
Topics: Humans; Diabetes Mellitus; Metabolic Syndrome; Insulin Resistance; Acromegaly; Graves Disease; Adrenal Gland Neoplasms
PubMed: 37628857
DOI: 10.3390/ijms241612676 -
Expert Opinion on Pharmacotherapy Apr 2021: In the past, controlling the hormone-excess-state was the main determinant of survival in Functional-Neuroendocrine-Neoplasm-syndromes (F-NENs). This was difficult...
: In the past, controlling the hormone-excess-state was the main determinant of survival in Functional-Neuroendocrine-Neoplasm-syndromes (F-NENs). This was difficult because the pharmacological-armamentarium available was limited. Recently, new therapeutic strategies have increased but it also generated controversies/uncertainties.: The authors briefly review: established/proposed F-NENs; the rationale for treatments; the recommended initial-pharmacotherapeutic-approach to controlling F-NENs hormone-excess-state; the secondary-approaches if the initial approach fails or resistance develops; and the approach to deal with the malignant nature of the NEN. Also discussed are controversies/uncertainties related to new treatments.: Unfortunately, except for patients with insulinomas (>90-95%), gastrinomas (<20-40%), a minority with the other F-panNENs and 0-<1% with Carcinoid-syndrome is curative-surgery possible. Except for insulinomas, gastrinomas, and ACTHomas, long-acting somatostatin-analogs are the initial-pharmacological-treatments for hormone-excess-state. For insulinomas prior to surgery/malignancy, diazoxide is the initial drug-treatment; for gastrinomas, oral PPIs; and for ACTHomas, steroidogenesis inhibitors. There are now several secondary pharmacotherapeutic treatments. Surgery and liver-directed therapies also have a role in selected patients. Particularly promising is the recent results with PRRT for the hormone-excess-state, independent of its anti-growth effect. The sequence to use various agents and the approach to syndrome diagnosis while taking various agents remains unclear/controversial in many cases.
Topics: Humans; Neuroendocrine Tumors; Pancreatic Neoplasms; Somatostatin
PubMed: 33131345
DOI: 10.1080/14656566.2020.1845651 -
In Vivo (Athens, Greece) 2023Pancreatic neuroendocrine tumors (PNETs) are pancreatic neoplasms with neuroendocrine features, divided into functioning and non-functioning. The non-functioning PNETs... (Review)
Review
BACKGROUND/AIM
Pancreatic neuroendocrine tumors (PNETs) are pancreatic neoplasms with neuroendocrine features, divided into functioning and non-functioning. The non-functioning PNETs are the largest group, and their morbidity is the result of their potential to invade surrounding tissues and metastasize. The functioning PNETs produce hormonal symptoms due to over-secretion of specific hormones. They constitute 1% to 2% of all pancreatic tumors. The use of novel imaging methods has rendered their detection more frequent. Insulinoma, the most common functioning PNET, comprises 35-40% of all functioning PNETs. Its clinical presentation is due to hyperinsulinemia and the subsequent hypoglycemia. Glucagonoma accounts for 5% of all PNETs and is the fourth most frequent functioning PNET, following insulinoma, gastrinoma, and vipoma. Its symptoms are due to the massive secretion of glucagon and ensuing hyperglycemia. The co-existence of two PNETs is a very rare entity. This report aimed to describe cases of concomitant insulinomas and glucagonomas.
MATERIALS AND METHODS
A review of the literature was performed using the PubMed database and Cochrane library aiming to identify reported cases of concomitant pancreatic insulinoma and glucagonoma. Specifically, the research was conducted using the keywords, separately and in various combination, including insulinoma, glucagonoma, cystic, pancreatic neuroendocrine tumors and hypoglycemia. Only publications in English were included in the present study.
RESULTS
A total of 8 cases of concomitant pancreatic insulinoma and glucagonoma were identified, corresponding to the period 1992-2021.
CONCLUSION
Concomitant insulinoma and glucagonoma are rare and challenging. A multidisciplinary approach is necessary for diagnosis, prognosis, and therapy.
Topics: Humans; Insulinoma; Glucagonoma; Neuroendocrine Tumors; Pancreatic Neoplasms; Hypoglycemia; Neuroectodermal Tumors, Primitive
PubMed: 37905620
DOI: 10.21873/invivo.13345