Se hela listan på hindawi.com

The two closely related RabGTPase-activating proteins (RabGAPs) TBC1D1 and TBC1D4 play a crucial role in the regulation of GLUT4 translocation in response to insulin and contraction in skeletal muscle. In mice, deficiency in one or both RabGAPs leads to reduced insulin and contraction-stimulated glucose uptake, and to elevated fatty acid uptake and oxidation in both glycolytic and oxidative

[75] Decreased lipolysis – forces reduction in conversion of fat cell lipid stores into blood fatty acids and glycerol; decrease of insulin causes the reverse. OBJECTIVE: Insulin control of fatty acid metabolism has long been deemed dominated by suppression of adipose lipolysis. The goal of the present study was to test the hypothesis that this single role of insulin is insufficient to explain observed fatty acid dynamics. Insulin- and leptin-regulated fatty acid uptake plays a key causal role in hepatic steatosis in mice with intact leptin signaling but not in ob/obor db/dbmice Fengxia Ge,1,*Shengli Zhou,1,*Chunguang Hu,1Harrison Lobdell, IV,1and Paul D. Berk1,2 Divisions of 1Digestive and Liver Disease and MCD inhibition also led to reduced palmitate uptake and decreased expression of fatty acid transport protein 1; conversely, glucose uptake in both the basal and insulin-stimulated states was enhanced in association with increased cell surface levels of GLUT4. The secretion of insulin may also be stimulated by certain amino acids, fatty acids, keto acids (products of fatty acid oxidation), and several hormones secreted by the gastrointestinal tract. Increased esterification of fatty acids – forces adipose tissue to make neutral fats (i.e., triglycerides) from fatty acids; decrease of insulin causes the reverse.

CAS Article PubMed Google Scholar An overabundance of fatty acids has long been known to induce insulin resistance. 5,6 Excessive fatty acid uptake into insulin-responsive tissues like skeletal muscle is thought to induce insulin Free fatty acids (FFA) are elevated in insulin-resistant states and are thought to play a critical role in the progression to type 2 diabetes. Palmitate is the predominant circulating saturated FFA. It is elevated in the insulin-resistant states [ 6 ] and known to induce insulin resistance in vitro [ 7 ]. The biochemical and molecular processes linking saturated fats to insulin resistance remain unresolved but may relate to altered membrane phospholipid fatty acid composition and membrane fluidity and stability , changes in lipogenic gene transcription , the type of fatty acids within TAG (2, 28), and direct interference with insulin signaling (8, 21, 41, 45, 51).

In mice, deficiency in one or both RabGAPs leads to reduced insulin and contraction-stimulated glucose uptake, and to elevated fatty acid uptake and oxidation in both glycolytic and oxidative Read "Insulin‐mediated vasodilation and glucose uptake are independently related to fasting serum nonesterified fatty acids in elderly men, Journal of Internal Medicine" on DeepDyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips. Role of fatty acid uptake and fatty acid beta-oxidation in mediating insulin resistance in heart and skeletal muscle. Fatty acids are a major fuel source used to sustain contractile function in heart and oxidative skeletal muscle.

Conclusion: Some fatty acids can act to inhibit GK activity in primary hepatocytes. However, there was no evidence that this decrease in GK activity impaired glucose phosphorylation or glycolysis. Glucose and high concentrations of insulin, which promote glucose uptake, appear to counteract any inhibitory action of fatty acids.

Insulin also stimulates protein synthesis, free fatty acid uptake and synthesis, as well as inhibiting lipolysis in adipocytes [10]. av N Franck · 2009 · Citerat av 2 — oxidation, liberation of fatty acids and glyceroneogenesis to be regulated attenuating insulin stimulated glucose uptake in muscle and adipose tissue and rate-limiting enzyme in fatty acid synthesis. Furthermore, we show that propionic acid and butyric acid increase insulin-stimulated glucose uptake. To conclude av S Barg — rate-limiting enzyme in fatty acid synthesis.

Mar 16, 2010 of the heart can regulate the uptake of fatty acids that we ingest through factor to the development of insulin resistance and type II diabetes.

1985) [5].Previous works have reported that FFAs are able to acutely induce 2012-06-21 2004-07-01 Insulin reduced CD36 ubiquitination, increased CD36 protein, and inhibited the opposite effects of fatty acids on both parameters. These changes were paralleled by changes in fatty acid uptake, which could be blocked by the CD36 inhibitor sulfosuccinimidyl oleate. 2012-03-12 2019-06-24 Interestingly, fatty acid uptake was reasonably well matched to the rate of fatty acid oxidation in NORM-S i (3.8±0.5 vs 3.7±0.2 μmol kg −1 min −1, respectively), but in LOW-S i the rate of 2012-09-14 2006-10-01 The biochemical and molecular processes linking saturated fats to insulin resistance remain unresolved but may relate to altered membrane phospholipid fatty acid composition and membrane fluidity and stability , changes in lipogenic gene transcription , the type of fatty acids within TAG (2, 28), and direct interference with insulin signaling (8, 21, 41, 45, 51). However, all fatty acids studied, except the saturated palmitic acid (16:0), increased insulin-stimulated glucose uptake and this effect did not appear to be specific to fatty acid series. The most marked effects on glucose uptake were observed with AA, which increased basal and insulin-stimulated glucose uptake at all time points studied. The rapid rise in the prevalence of obesity and diabetes has significantly contributed to the increasing global burden of noncommunicable diseases. Insulin resistance is a major underpinning etiology of both obesity and type 2 diabetes.

After prolonged exposure to high fatty acid concentrations this changes to an inhibition. We concluded that fatty acids caused a dose-dependent inhibition of insulin-stimulated glucose uptake (by decreasing glycogen synthesis and CHO oxidation) and that FFA and/or glycerol increased insulin-suppressed hepatic glucose output and thus caused insulin resistance at the peripheral and the hepatic level. Altered muscle fatty acid (FA) metabolism may contribute to the presence of muscle insulin resistance in the genetically obese Zucker rat. To determine whether FA uptake and disposal are altered in insulin-resistant muscle, we measured palmitate uptake, oxidation, and incorporation into di- and triglycerides in isolated rat hindquarters, as well as muscle plasma membrane fatty acid–binding There is strong support for the notion that free fatty acids (FFAs) are an important link between obesity, insulin resistance, and type 2 diabetes. Myocardial fatty acid utilization rate depends on the availability of exogenous fatty acids and the rate of acetyl-CoA oxidation . When plasma glucose and insulin levels are increased, the heart preferentially uses glucose, and fatty acid uptake and oxidation are suppressed (27, 34).
Vad skriva i kalender

The goal of the present study was to test the hypothesis that this single role of insulin is insufficient to explain observed fatty acid dynamics. Insulin also reduced [3H]oleic acid uptake up to 35%, depending on insulin concentration and decreased the amount of fatty acid esterified into the phospholipids and neutral lipids by 28 and 70%, respectively.

Since insulin resistance and type II diabetes in humans are characterised by high glucose levels and the reduced uptake of sugar to the muscles, it is hoped that av TJ Horton · 2001 · Citerat av 56 — The FSIGTT gives both the insulin sensitivity index and glucose effectiveness as cose-fatty acid cycle as first proposed by Randle et al.
B2b b2c b2e

This animation helps the learner to understand the lipid abnormalities commonly seen in patients with type 2 diabetes. The animation focuses on the major rol

From Dimitriadis and Newsholme, reproduced with permission. Defective fatty acid uptake modulates insulin responsiveness and metabolic responses to diet in CD36-null mice Tahar Hajri, 1 Xiao Xia Han, 2 Arend Bonen, 2 and Nada A. Abumrad 1 1 Department of Physiology and Biophysics, State University of New York at Stony Brook, Stony Brook, New York, USA 2 Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada To study effects of sex on free fatty acid (FFA)-induced insulin resistance, we have examined the effects of acute elevations of plasma FFA levels on insulin-stimulated total body glucose uptake in nine healthy young women. Euglycemic-hyperinsulinemic (∼500 pmol/l) clamps were performed for 4 h with coinfusion of either lipid/heparin (L/H) to acutely raise plasma FFA levels (from ∼600 to 2015-09-29 · Insulin resistance is a multi-faceted disruption of the communication between insulin and the interior of a target cell.

There is strong support for the notion that free fatty acids (FFAs) are an important link between obesity, insulin resistance, and type 2 diabetes.

To meet the energy demands of these muscles, the uptake and beta-oxidation of fatty acids must be coordinately CONCLUSIONS: These results support insulin regulation of fatty acid turnover by both release and uptake mechanisms. Activation of fatty acid uptake is consistent with the human data, has mechanistic precedent in cell culture, and highlights a new potential target for therapies aimed at improving the control of fatty acid metabolism in insulin-resistant disease states.

2009-06-25 2015-03-13 This animation helps the learner to understand the lipid abnormalities commonly seen in patients with type 2 diabetes. The animation focuses on the major rol Fat-Cells, Glucose, Insulin, Fatty Acids and Diabetes - YouTube. Insulin is a protein composed of two chains, an A chain (with 21 amino acids) and a B chain (with 30 amino acids), which are linked together by sulfur atoms. Insulin is derived from a 74-amino-acid prohormone molecule called proinsulin.Proinsulin is relatively inactive, and under normal conditions only a small amount of it is secreted.