Overexpression of Vesicle-associated Membrane Protein (VAMP) 3, but Not VAMP2, Protects Glucose Transporter (GLUT) 4 Protein Translocation in anin VitroModel of Cardiac Insulin Resistance

Insulin stimulates glucose transport in adipocytes by translocation of the glucose transporter (GLUT-4) from an intracellular site to the cell surface. We have characterized different synaptobrevin/vesicle-associated membrane protein (VAMP) homologues in adipocytes and studied their intracellular distribution with respect to GLUT-4. VAMP-1, VAMP-2, and cellubrevin cDNAs were isolated from a 3T3-L1 adipocyte expression library. VAMP-2 and cellubrevin were: (a) the most abundant isoforms in adipocytes, (b) detectable in all insulin responsive tissues, (c) translocated to the cell surface in response to insulin, and (d) found in immunoadsorbed GLUT-4 vesicles. To further define their intracellular distribution, 3T3-L1 adipocytes were incubated with a transferrin/HRP conjugate (Tf/HRP) and endosomes ablated following addition of DAB and H2O2. While this resulted in ablation of > 90% of the transferrin receptor (TfR) and cellubrevin found in intracellular membranes, 60% of GLUT-4 and 90% of VAMP-2 was not ablated. Immuno-EM on intracellular vesicles from adipocytes revealed that VAMP-2 was colocalized with GLUT-4, whereas only partial colocalization was observed between GLUT-4 and cellubrevin. These studies show that two different v-SNAREs, cellubrevin and VAMP-2, are partially segregated in different intracellular compartments in adipocytes, implying that they may define separate classes of secretory vesicles in these cells. We conclude that a proportion of GLUT-4 is found in recycling endosomes in nonstimulated adipocytes together with cellubrevin and the transferrin receptor. In addition, GLUT-4 and VAMP-2 are selectively enriched in a postendocytic compartment. Further study is required to elucidate the function of this latter compartment in insulin-responsive cells.

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Association of polycystic ovary syndrome with insulin resistance and glucose transporter GLUT 4.

The Professional Medical Journal ◽

10.29309/tpmj/2020.27.10.4353 ◽

2020 ◽

Vol 27 (10) ◽

pp. 2182-2186

Author(s):

Roohi Jabbar ◽

Rukhshan Khurshid ◽

Uzma Jabbar ◽

Mudassir Zia ◽

Abeera Mazhar Siddiqui ◽

...

Keyword(s):

Insulin Resistance ◽

Glucose Transporter ◽

Fasting Glucose ◽

Polycystic Ovary ◽

Cross Sectional Study ◽

Cross Sectional ◽

Glut 4 ◽

History Of ◽

Age Range ◽

Study Setting

Objectives: The study was designed to find out the association of PCOS with insulin resistance and GLUT4. Study Design: Cross Sectional study. Setting: Outdoor Department of Sir Ganga Ram Hospital Lahore. Period: March 2016 to December 2016. Material & Methods: 37 PCOS women visited Outdoor Department of Sir Ganga Ram Hospital Lahore. Their age range was 25- 36 years. 20 ages matched medical staff of the Sir Ganga Ram Hospital, Lahore with no history of any disease were selected as control. Rotterdam’s criteria were used to confirm PCOS. Levels of circulating insulin, GLUT 4 and fasting glucose were estimated. Results: Mean age of PCOS patients and of controls was 30.55 and 29.00 years respectively. Values of BMI were insignificantly raised in PCOS in comparison to controls. Levels of circulating GLUT-4, fasting glucose, insulin and resistance of insulin were increased significantly in women with PCOS in comparison to the controls. Decreased ratio of glucose to insulin was seen in PCOS women in comparison to their controls. Conclusion: A good association of PCOS was observed with insulin mediated release of glucose transporter GLUT 4 and insulin resistance.

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Adipocytes Exhibit Abnormal Subcellular Distribution and Translocation of Vesicles Containing Glucose Transporter 4 and Insulin-Regulated Aminopeptidase in Type 2 Diabetes Mellitus: Implications Regarding Defects in Vesicle Trafficking

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jcem.86.11.8053 ◽

2001 ◽

Vol 86 (11) ◽

pp. 5450-5456 ◽

Cited By ~ 35

Author(s):

Lidia Maianu ◽

Susanna R. Keller ◽

W. Timothy Garvey

Keyword(s):

Insulin Resistance ◽

Type 2 Diabetes ◽

Body Mass Index ◽

Body Mass ◽

Glucose Transporter ◽

Diabetic Patients ◽

Low Density ◽

Glucose Transporter 4 ◽

Glut 4

Insulin resistance in type 2 diabetes is due to impaired stimulation of the glucose transport system in muscle and fat. Different defects are operative in these two target tissues because glucose transporter 4 (GLUT 4) expression is normal in muscle but markedly reduced in fat. In muscle, GLUT 4 is redistributed to a dense membrane compartment, and insulin-mediated translocation to plasma membrane (PM) is impaired. Whether similar trafficking defects are operative in human fat is unknown. Therefore, we studied subcellular localization of GLUT4 and insulin-regulated aminopeptidase (IRAP; also referred to as vp165 or gp160), which is a constituent of GLUT4 vesicles and also translocates to PM in response to insulin. Subcutaneous fat was obtained from eight normoglycemic control subjects (body mass index, 29 ± 2 kg/m2) and eight type 2 diabetic patients (body mass index, 30 ± 1 kg/m2; fasting glucose, 14 ± 1 mm). In adipocytes isolated from diabetics, the basal 3-O-methylglucose transport rate was decreased by 50% compared with controls (7.1 ± 2.9 vs. 14.1 ± 3.7 mmol/mm2 surface area/min), and there was no increase in response to maximal insulin (7.9 ± 2.7 vs. 44.5 ± 9.2 in controls). In membrane subfractions from controls, insulin led to a marked increase of IRAP in the PM from 0.103 ± 0.04 to 1.00± 0.33 relative units/mg protein, concomitant with an 18% decrease in low-density microsomes and no change in high-density microsomes (HDM). In type 2 diabetes, IRAP overall expression in adipocytes was similar to that in controls; however, two abnormalities were observed. First, in basal cells, IRAP was redistributed away from low-density microsomes, and more IRAP was recovered in HDM (1.2-fold) and PM (4.4-fold) from diabetics compared with controls. Second, IRAP recruitment to PM by maximal insulin was markedly impaired. GLUT4 was depleted in all membrane subfractions (43–67%) in diabetes, and there was no increase in PM GLUT4 in response to insulin. Type 2 diabetes did not affect the fractionation of marker enzymes. We conclude that in human adipocytes: 1) IRAP is expressed and translocates to PM in response to insulin; 2) GLUT4 depletion involves all membrane subfractions in type 2 diabetes, although cellular levels of IRAP are normal; and 3) in type 2 diabetes, IRAP accumulates in membrane vesicles cofractionating with HDM and PM under basal conditions, and insulin-mediated recruitment to PM is impaired. Therefore, in type 2 diabetes, adipocytes express defects in trafficking of GLUT4/IRAP-containing vesicles similar to those causing insulin resistance in skeletal muscle.

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Insulin resistance and GLUT-4 glucose transporter in adipocytes from hypertensive rats

Metabolism ◽

10.1016/j.metabol.2003.10.017 ◽

2004 ◽

Vol 53 (3) ◽

pp. 382-387 ◽

Cited By ~ 11

Author(s):

Gladys E Chiappe De Cingolani ◽

Claudia I Caldiz

Keyword(s):

Insulin Resistance ◽

Glucose Transporter ◽

Hypertensive Rats ◽

Glut 4

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Increased Expression of the Tail-Anchored Membrane Protein SLMAP in Adipose Tissue from Type 2Tally HoDiabetic Mice

Experimental Diabetes Research ◽

10.1155/2011/421982 ◽

2011 ◽

Vol 2011 ◽

pp. 1-10 ◽

Cited By ~ 6

Author(s):

Xiaoliang Chen ◽

Hong Ding

Keyword(s):

Adipose Tissue ◽

Membrane Protein ◽

Glucose Uptake ◽

Glucose Transporter ◽

Single Gene ◽

Abdominal Adipose Tissue ◽

Glut 4 ◽

Important Regulator ◽

Chromosome 3P14

The tail-anchored membrane protein, sarcolemmal membrane associated protein (SLMAP) is encoded to a single gene that maps to the chromosome 3p14 region and has also been reported in certain diabetic populations. Our previous studies with db/db mice shown that a deregulation of SLMAP expression plays an important role in type 2 diabetes. MaleTally Homice were bred to present with either normoglycemia (NG) or hyperglycemia (HG). Abdominal adipose tissue from maleTally Homice of the HG group was found to have a significantly lower expression of the membrane associated glucose transporter-4 (GLUT-4) and higher expression of SLMAP compared to tissue from NG mice. There were 3 isoforms expressed in the abdominal adipose tissue, but only 45?kDa isoform of SLMAP was associated with the GLUT-4 revealed by immunoprecipitation data. Knock down studies using SLMAP siRNA with adipocytes resulted in a significant reduction in SLMAP and a decrease in glucose uptake. Thus, SLMAP may be an important regulator of glucose uptake or involved in GLUT-4 fusion/translocation into the plasma membrane of mouse abdominal adipose tissue and changes in SLMAP expression are linked to hyperglycemia and diabetes.

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Pengaruh Latihan Fisik terhadap Perbaikan Resistensi Insulin

KELUWIH: Jurnal Kesehatan dan Kedokteran ◽

10.24123/kesdok.v2i2.4033 ◽

2021 ◽

Vol 2 (2) ◽

pp. 110-114

Author(s):

Devitya Angielevi Sukarno

Keyword(s):

Insulin Resistance ◽

Blood Glucose ◽

Protein Kinase ◽

Cell Membrane ◽

Blood Glucose Level ◽

Insulin Signaling ◽

Glucose Transporter ◽

Insulin Receptor Substrate ◽

Glucose Transporter 4 ◽

Glut 4

Abstract--Insulin resistance underlies the pathogenesis of chronic disease, such as diabetes mellitus which has high morbidity and mortality rate. Insulin resistance is a pathological condition when cells fail to respond normally to the insulin hormone, because of insulin signaling pathway disruption. Bound between insulin and insulin’s receptor cannot phosphorylate tyrosine and fail to activate insulin receptor substrate-1 (IRS-1). This failure decrease Glucose transporter-4 (GLUT-4) expression on the skeletal muscle’s cell membrane, that leads to decrease glucose influx and increase blood glucose level. A routine physical training which does according to adequate training dose, will activate adenosin 5’monophosphate-activated protein kinase (AMPK) and lead to the translocation of GLUT-4 vesicles without insulin and insulin’s receptor bonding.GLUT-4 expression on the skeletal muscle’s cell membrane which is stimulated by muscle contraction will increase glucose influx and decrease blood glucose level. Keywords: insulin resistance; physical training; insulin signaling pathway Abstrak--Resistensi insulin merupakan penyebab yang mendasari terjadinya penyakit kronis seperti diabetes melitus yang memiliki angka morbiditas dan mortalitas tinggi.Resistensi insulin merupakan keadaan patologis dimana terjadi kegagalan respon seluler terhadap hormon insulin akibat gangguan pada jalur sinyal insulin.Ikatan insulin pada reseptornya tidak dapat menyebabkan fosforilasi tirosin sehingga tidak dapat mengaktivasi insulin receptor substrate-1 (IRS-1). Kegagalan aktivasi tersebut akan menyebabkan penurunan ekspresi Glucose transporter-4 (GLUT-4) pada membran sel otot rangka sehingga ambilan glukosa oleh sel menurun dan glukosa darah meningkat. Latihan fisik yang dilakukan secara rutin, teratur dan sesuai dengan dosis latihan yang tepat dapat mengaktivasi adenosin 5’monophosphate-activated protein kinase (AMPK), sehingga menyebabkan translokasi vesikel berisi GLUT-4, tanpa melalui ikatan insulin dengan reseptornya. Ekspresi GLUT-4 pada membran sel yang dirangsang oleh kontraksi otot akan meningkatkan ambilan glukosa dan menurunkan glukosa darah. Kata kunci: resistensi insulin; latihan fisik; jalur sinyal insulin

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Muscle insulin resistance in uremic humans: glucose transport, glucose transporters, and insulin receptors

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1991.261.1.e87 ◽

1991 ◽

Vol 261 (1) ◽

pp. E87-E94 ◽

Cited By ~ 9

Author(s):

J. E. Friedman ◽

G. L. Dohm ◽

C. W. Elton ◽

A. Rovira ◽

J. J. Chen ◽

...

Keyword(s):

Insulin Resistance ◽

Skeletal Muscle ◽

Glucose Transport ◽

Glucose Transporter ◽

Insulin Receptors ◽

Glucose Disposal ◽

Intravenous Glucose ◽

Transporter Protein ◽

Glut 4 ◽

Uremic Patients

To determine the cellular basis for insulin resistance observed in patients with uremia, we investigated insulin action in vivo and in vitro using skeletal muscle obtained from patients with chronic renal failure. Uremic subjects had significantly reduced rates of insulin-stimulated glucose disposal, as determined by a 3-h intravenous glucose tolerance test and using the hyperinsulinemic euglycemic clamp technique. Hepatic glucose production was similar before (control, 76.2 +/- 6.3 vs. uremic, 74.2 +/- 6.9 mg.kg-1.min-1) and during insulin infusion at 40 mU.m-2.min-1 (control, -60.9 +/- 6.6 vs. uremic, -53.9 +/- 6.3 mg.kg-1.min-1). In incubated human skeletal muscle fiber strips, basal 2-deoxy-D-glucose transport was unchanged in uremic subjects compared with controls. However, the increase in insulin-stimulated glucose transport was significantly reduced by 50% in muscles from uremic patients (P = 0.012). In partially purified insulin receptors prepared from skeletal muscle, 125I-labeled insulin binding, beta-subunit receptor autophosphorylation, and tyrosine kinase activity were all unchanged in uremic subjects. The abundance of insulin-sensitive (muscle/fat, GLUT-4) glucose transporter protein measured by Western blot using Mab 1F8 or polyclonal antisera was similar in muscles of control and uremic patients. These findings suggest that the insulin resistance observed in skeletal muscle of uremic patients cannot be attributed to defects in insulin receptor function or depletion of the GLUT-4 glucose transporter protein. An alternative step in insulin-dependent activation of the glucose transport process may be involved.

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Expression of GLUT-4 glucose transporter in unweighted soleus muscle of normal and STZ-induced diabetic rats

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1993.264.2.e301 ◽

1993 ◽

Vol 264 (2) ◽

pp. E301-E307 ◽

Cited By ~ 1

Author(s):

H. Ishihara ◽

T. Asano ◽

H. Katagiri ◽

J. L. Lin ◽

K. Tsukuda ◽

...

Keyword(s):

Membrane Protein ◽

Soleus Muscle ◽

Glucose Transporter ◽

Weight Bearing ◽

Diabetic Rats ◽

Hindlimb Suspension ◽

Glut 4 ◽

Mrna Ratio ◽

Longus Muscle ◽

Total Membrane

Effects of 6 days of hindlimb suspension on expression of glucose transporters were studied in the skeletal muscle of nondiabetic and streptozotocin-induced diabetic rats. Although total membrane protein recovered from soleus muscles tended to decrease with suspension, GLUT-4 protein concentration (amount per gram membrane protein) was increased by 66 and 91% compared with weight-bearing control in nondiabetic and diabetic rats, respectively. Therefore, the amount of GLUT-4 protein in whole soleus muscle did not decrease with the hindlimb suspension in normal and diabetic rats. In contrast, hindlimb suspension decreased GLUT-4 mRNA amount in whole soleus muscle by 47 and 27% in nondiabetic and diabetic rats, respectively. Thus the GLUT-4 protein-to-GLUT-4 mRNA ratio was increased 2.1-fold in nondiabetic and 1.4-fold in diabetic rats. The extensor digitorum longus muscle, which generally shows little response to unweighting, exhibited no such changes. These results suggest that the amount of GLUT-4 glucose transporter in the unweighted soleus muscle was maintained via a translational and/or posttranslational mechanism in nondiabetic rats as well as in streptozotocin-induced diabetic rats under the condition of reduced weight-bearing activity.

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