Search results for "insulin"

Identification of a discrete neuronal circuit that relays insulin signaling into the brain to regulate glucose homeostasis

2021

Abstract26RFa (QRFP) is a biologically active peptide that regulates glucose homeostasis by acting as an incretin and by increasing insulin sensitivity at the periphery. 26RFa is also produced by a neuronal population localized in the hypothalamus. In the present study, we have investigated whether the 26RFa neurons may be involved in the hypothalamic regulation of glucose homeostasis. Our data indicate that 26RFa, i.c.v. injected, induces a robust antihyperglycemic effect associated with an increase of insulin production by the pancreatic islets. In addition, we found that insulin strongly stimulates 26RFa expression and secretion by the hypothalamus. RNAscope experiments revealed that neu…

Effects of repeated treatments with an extract ofGinkgo biloba (EGb 761) and bilobalide on liver and muscle glycogen contents in the non-insulin-depe…

1997

The effects of repeated (15-day) oral treatments with an extract of Ginkgo biloba (EGb 761; 50 mg/kg/day) or with its terpenoid constituent, bilobalide (2 mg/kg/day), were assessed in normal rats and in rats that had been previously injected with streptozotocin (50 mg/kg, i.p. in saline solution), a dose which provided a model of non-insulin-dependent diabetes mellitus (NIDDM). In this model of diabetes, blood glucose is significantly increased while the circulating insulin level remains unchanged. Glucose penetrates cells because of decreased glycogen turnover, a metabolic abnormality that can be revealed by using an oral glucose tolerance test (OGTT). In control rats, hyperglycemia was ac…

MAGNESIUM METABOLISM IN INSULIN RESISTANCE, METABOLIC SYNDROME, AND TYPE 2 DIABETES MELLITUS

2007

Magnesium plays a key role in regulating insulin action, insulin-mediated glucose uptake, and vascular tone. Intracellular magnesium depletion may result in a defective tyrosine—kinase activity at the insulin receptor level, in a postreceptorial impairment in insulin action, and clinically in a worsening of insulin resistance. Intra- and extracellular alterations of magnesium metabolism have been identified in clinical states characterized by insulin resistance, such as metabolic syndrome, hypertension, altered glucose tolerance, type 2 diabetes, and aging. Several studies, from our and other’s groups, have confi rmed the clinical relevance of alterations of magnesium homeostasis in these c…

SIRT1 regulation of insulin-signalling pathways in liver, white adipose tissue and pancreas during fasting or calorie restriction

2007

In an excellent review by Yang et al.[1], published in issue 5 of Trends in Endocrinology and Metabolism, the involvement of the human sirtuin SIRT1 in nutrient-sensing and insulin-signalling pathways is explained. The regulation of SIRT1 with fasting in liver, pancreas and white adipose tissue is illustrated (see Figure 2 of Yang et al.). We consider that the depiction in the article by Yang et al. could be misleading for the reader, and we propose a modified version (Figure 1).

No effect of oral insulin on residual beta-cell function in recent-onset Type I diabetes (the IMDIAB VII)

2000

Aims/hypothesis. Induction of tolerance to insulin is achievable in animal models of Type I (insulin-dependent) Diabetes mellitus by oral treatment with this hormone, which can lead to prevention of the disease. In the Diabetes Prevention Trial of Type I diabetes (DPT-1), oral insulin is given with the aim of preventing disease insurgence. We investigated whether if given at diagnosis of Type I diabetes in humans, oral insulin can still act as a tolerogen and therefore preserve residual beta-cell function, which is known to be substantial at diagnosis. Methods. A double-blind trial was carried out in patients (mean age ± SD: 14 ± 8 years) with recent-onset Type I diabetes to whom oral insul…

Type 2 diabetes mellitus and Alzheimer’s disease

2014

Epidemiological and biological evidences support a link between type 2 diabetes mellitus (DM2) and Alzheimer’s disease (AD). Persons with diabetes have a higher incidence of cognitive decline and an increased risk of developing all types of dementia. Cognitive deficits in persons with diabetes mainly affect the areas of psychomotor efficiency, attention, learning and memory, mental flexibility and speed, and executive function. The strong epidemiological association has suggested the existence of a physiopathological link. The determinants of the accelerated cognitive decline in DM2, however, are less clear. Increased cortical and subcortical atrophy have been evidenced after controlling fo…

Glucagon-like peptide-2 analog and inflammatory state in obese mice

2020

Obesity is characterized by chronic low grade of systemic inflammation that develops in response to nutrient excess and plays a key role in the pathogenesis of insulin resistance. It is characterized by macrophage infiltration into adipose tissue (AT) and abnormal cytokine production. These factors damage the metabolic homeostasis leading to alteration in the insulin signaling in specific tissues and organs such as AT and liver. Thus, obese subjects develop over the time resistance to the cellular actions of insulin. Glucagon like peptide-2 (GLP-2) is an intestinal proglucagon-derived hormone released together with GLP1, in response to the passage of food by the distal small intestine. Once…

Insulin resistance and familial dyslipidaemias

1999

Risposta insulo-secretrice al carico endovenoso di tolbutamide

1968

Gli AA. hanno studiato il comportamento della risposta insulinemica dopo stimolazione con tolbutamide endovenosa in un piccolo gruppo di soggetti normali normosomici, obesi non diabetici e diabetici obesi. In tutti i soggetti il massimo aumento dell'insulinemia (determinata con metodo radio-immunologico) compare a 5 mp ed e maggiore negli obesi rispetto ai normali e ai diabetici. La caduta percentuale del picco insulinemico dimostra un andamento parallelo nei normali e negli obesi, mentre e molto piu lenta nei diabetici obesi. Vengono discusse le cause di questo comportamento e la natura dell'iperinsulinismo presente nell'obesita con e senza diminuita tolleranza agli idrati di carbonio.

Effects of hypolipidemic and hypoglycemic agents on atherogenic small, dense LDL in Type 2 diabetes

2011

Type 2 diabetes is associated with a cluster of inter-related plasma lipid and lipoprotein abnormalities, including reduced HDL-C, a predominance of small, dense LDL and elevated triglycerides. These abnormalities occur even in prediabetes, before blood sugars rise sufficiently in order to confirm a diagnosis of diabetes, and this transition phase incurs important cardiovascular risk. This is the rationale for paying attention to dyslipidemia through the use of the hypolipidemic, rather than hypoglycemic drugs only. A literature search (by Medline and Scopus) was performed. The authors also manually reviewed the references of selected articles for any pertinent material. Beyond the ‘quantit…