Insulin binding to individual rat skeletal muscles

1990 ◽  
Vol 259 (4) ◽  
pp. E517-E523 ◽  
Author(s):  
D. J. Koerker ◽  
I. R. Sweet ◽  
D. G. Baskin
Keyword(s):  
Skeletal Muscle ◽  
Insulin Sensitivity ◽  
Binding Sites ◽  
Skeletal Muscles ◽  
Dissociation Constants ◽  
Binding Capacity ◽  
Fiber Type ◽  
Insulin Binding ◽  
Computer Assisted ◽  
Hindlimb Muscles

Studies of insulin binding to skeletal muscle, performed using sarcolemmal membrane preparations or whole muscle incubations of mixed muscle or typical red (soleus, psoas) or white [extensor digitorum longus (EDL), gastrocnemius] muscle, have suggested that red muscle binds more insulin than white muscle. We have evaluated this hypothesis using cryostat sections of unfixed tissue to measure insulin binding in a broad range of skeletal muscles; many were of similar fiber-type profiles. Insulin binding per square millimeter of skeletal muscle slice was measured by autoradiography and computer-assisted densitometry. We found a 4.5-fold range in specific insulin tracer binding, with heart and predominantly slow-twitch oxidative muscles (SO) at the high end and the predominantly fast-twitch glycolytic (FG) muscles at the low end of the range. This pattern reflects insulin sensitivity. Evaluation of displacement curves for insulin binding yielded linear Scatchard plots. The dissociation constants varied over a ninefold range (0.26-2.06 nM). Binding capacity varied from 12.2 to 82.7 fmol/mm2. Neither binding parameter was correlated with fiber type or insulin sensitivity; e.g., among three muscles of similar fiber-type profile, the EDL had high numbers of low-affinity binding sites, whereas the quadriceps had low numbers of high-affinity sites. In summary, considerable heterogeneity in insulin binding was found among hindlimb muscles of the rat, which can be attributed to heterogeneity in binding affinities and the numbers of binding sites. It can be concluded that a given fiber type is not uniquely associated with a set of insulin binding parameters that result in high or low binding.

Effect of training on insulin binding to rat skeletal muscle sarcolemmal vesicles

1986 ◽  
Vol 250 (5) ◽  
pp. E570-E575
Author(s):  
G. K. Grimditch ◽  
R. J. Barnard ◽  
S. A. Kaplan ◽  
E. Sternlicht
Keyword(s):  
Skeletal Muscle ◽  
Insulin Sensitivity ◽  
Exercise Training ◽  
Insulin Binding ◽  
Whole Body ◽  
Rat Skeletal Muscle ◽  
Binding Studies ◽  
Muscle Enzyme ◽  
Intravenous Glucose ◽  
High Affinity

We examined the hypothesis that the exercise training-induced increase in skeletal muscle insulin sensitivity is mediated by adaptations in insulin binding to sarcolemmal (SL) insulin receptors. Insulin binding studies were performed on rat skeletal muscle SL isolated from control and trained rats. No significant differences were noted between groups in body weight or fat. An intravenous glucose tolerance test showed an increase in whole-body insulin sensitivity with training, and specific D-glucose transport studies on isolated SL vesicles indicated that this was due in part to adaptations in skeletal muscle. Enzyme marker analyses revealed no differences in yield, purity, or contamination of SL membranes between the two groups. Scatchard analyses indicated no significant differences in the number of insulin binding sites per milligram SL protein on the high-affinity (15.0 +/- 4.1 vs. 18.1 +/- 6.4 X 10(9)) or on the low-affinity portions (925 +/- 80 vs. 884 +/- 106 X 10(9)) of the curves. The association constants of the high-affinity (0.764 +/- 0.154 vs. 0.685 +/- 0.264 X 10(9) M-1) and of the low affinity sites (0.0096 +/- 0.0012 vs. 0.0102 +/- 0.0012 X 10(9) M-1) also were similar. These results do not support the hypothesis that the increased sensitivity to insulin after exercise training is due to changes in SL insulin receptor binding.

scholarly journals Influence of low- and high-protein diets on insulin and insulin-like growth factor-1 binding to skeletal muscle and liver in the growing rat

1991 ◽  
Vol 65 (1) ◽  
pp. 47-60 ◽  
Author(s):  
D. Dardevet ◽  
M. Manin ◽  
M. Balage ◽  
C. Sornet ◽  
J. Grizard
Keyword(s):  
Skeletal Muscle ◽  
Growth Factor ◽  
Dietary Protein ◽  
Binding Capacity ◽  
Plasma Concentrations ◽  
Insulin Binding ◽  
Metabolic Adaptation ◽  
Scatchard Analysis ◽  
Insulin Like Growth Factor ◽  
Hormone Binding

The influence of protein content of the diet on the plasma concentrations and binding to skeletal muscle and liver of insulin and insulin-like growth factor-1 (IGF-1), was studied in growing rats. Animals with a starting body-weight of 80 g received for an 11 d period isoenergetic diets containing (g/kg dry matter) 155 protein as controls (MP), or 55 (LP) or 300 (HP) protein. Food was offered as six equal meals/d. Daily food intakes provided adequate amounts of energy. Total plasma IGF-1 increased linearly as a function of dietary protein intake. Plasma insulin was lower in the LP than in the MP and HP groups. Hormone binding was studied in wheat-germ agglutinin (WGA) partially purified skeletal muscle receptor preparations. Each 125I-labelled hormone binding was competed for by increasing amounts of homologous and heterologous unlabelled hormone; this displacement needed lower concentrations of homologous than heterologous hormone. When compared with MP-diet feeding, the LP diet resulted in an increased ligand concentration for half-maximal binding. In addition the specific 125I-labelled insulin and 125I-labelled IGF-1 binding increased at all hormone concentrations and, as revealed by Scatchard analysis, the hormone binding capacity also rose (only significant for low-affinity insulin receptors and high-affinity IGF-1 receptors). The HP diet had little effect on hormone binding, except to increase insulin binding at very low insulin concentrations. Hormone binding was further studied in WGA partially purified liver receptor preparations. Those preparations did not exhibit any detectable specific 125I-labelled IGF-1 binding. The specific 125I-labelled insulin binding was not altered by dietary protein level. It is concluded that the increase in skeletal muscle insulin and IGF-1 binding along with a decrease in insulin and IGF-1 in the blood from rats fed on the LP diet, is consistent with the concept of an inverse relationship between plasma hormone and hormone binding. The physiological significance with respect to metabolic adaptation of muscle remains to be established

Insulin Binding Sites Induced in the Tetrahymena by Rat Liver Receptor Antibody

1984 ◽  
Vol 39 (1-2) ◽  
pp. 183-185 ◽  
Author(s):  
G. Csaba ◽  
P. Kovács ◽  
Ágnes Inczefi-Gonda
Keyword(s):  
Rat Liver ◽  
Concanavalin A ◽  
Binding Sites ◽  
Binding Capacity ◽  
Insulin Receptors ◽  
Insulin Binding ◽  
Receptor Antibody ◽  
Receptor Antibodies

Abstract Tetrahvmena cells treated with purified rabbit anti­ bodies to rat hepatocellular membrane exhibited a consider­ able increase in binding capacity on reexposure to the antibody 24 h later. Insulin binding was similarly enhanced by preexposure to the antibody, and vice versa, preex­ posure to insulin enhanced the later binding of rat liver receptor antibodies. This suggests that (1) the Tetrahymena and the rat possess similar insulin receptors, and (2) the receptor antibody is also able to induce imprinting for itself as well as for insulin. Concanavalin-A, noted for binding overlap with insulin, failed to induce imprinting either for insulin or for antibodies to receptors, whereas the latter did induce imprinting for Concanavalin-A.

scholarly journals MON-613 The Expression of TBC1 Domain Family, Member 4 (TBC1D4) in Skeletal Muscles of Insulin-Resistant Mice in Response to Sulforaphane

2020 ◽  
Vol 4 (Supplement_1) ◽  
Author(s):  
Nasser M Rizk ◽  
Amina Saleh ◽  
Abdelrahman ElGamal ◽  
Dina Elsayegh ◽  
Isin Cakir ◽  
...  
Keyword(s):  
Gene Expression ◽  
Skeletal Muscle ◽  
Blood Glucose ◽  
Insulin Sensitivity ◽  
Skeletal Muscles ◽  
Glucose Disposal ◽  
Domain Family ◽  
Insulin Resistant ◽  
Glucose Levels ◽  
Blood Glucose Levels

Abstract The Expression of TBC1 Domain Family, member 4 (TBC1D4) in Skeletal Muscles of Insulin-Resistant Mice in Response to Sulforaphane. Background: Obesity is commonly accompanied by impaired glucose homeostasis. Decreased glucose transport to the peripheral tissues, mainly skeletal muscle, leads to reduced total glucose disposal and hyperglycemia. TBC1D4 gene is involved in the trafficking of GLUT4 to the outer cell membrane in skeletal muscle. Sulforaphane (SFN) has been suggested as a new potential anti-diabetic compound acting by reducing blood glucose levels through mechanisms not fully understood (1). The aim of this study is to investigate the effects SFN on TBC1D4 and GLUT4 gene expression in skeletal muscles of DIO mice, in order to elucidate the mechanism(s) through which SFN improves glucose homeostasis. Methodology: C57BL/6 mice (n=20) were fed with a high fat diet (60%) for 16 weeks to generate diet induced obese (DIO) mice with body weights between 45–50 gm. Thereafter, DIO mice received either SFN (5mg/kg BW) (n=10) or vehicle (n=10) as controls daily by intraperitoneal injections for four weeks. Glucose tolerance test (1g/kg BW, IP) and insulin sensitivity test (ITT) were conducted (1 IU insulin/ g BW, IP route) at the beginning and end of the third week of the injection. At the end of 4 weeks of the injection, samples of blood and skeletal muscles of both hindlimbs were collected. The expression levels of GLUT4 and TBC1D4 genes were analyzed by qRT-PCR. Blood was also used for glucose, adiponectin and insulin measurements. Results: SFN-treated DIO mice had significantly lower non-fasting blood glucose levels than vehicle-treated mice (194.16 ± 14.12 vs. 147.44 ± 20.31 mg/dL, vehicle vs. SFN, p value=0.0003). Furthermore, GTT results indicate that the blood glucose levels at 120 minutes after glucose infusion in was (199.83±34.53 mg/dl vs. 138.55±221.78 mg/dl) for vehicle vs. SFN with p=0.0011 respectively. ITT showed that SFN treatment did not enhance insulin sensitivity in DIO mice. Additionally, SFN treatment did not significantly change the expression of TBC1D4, and GLUT4 genes in skeletal muscles compared to vehicle treatment (p values >0.05). Furthermore, SFN treatment did not significantly affect the systemic insulin (1.84±0.74 vs 1.54±0.55 ng/ml, p=0.436), or adiponectin (11.96 ±2.29 vs 14.4±3.33 ug/ml, p=0.551) levels in SFN vs. vehicle-treated DIO mice, respectively. Conclusion: SFN treatment improves glucose disposal in DIO mice, which is not linked to the gene expression of GLUT4 and TBC1D4 and its mechanism of glucose disposal in skeletal muscles. Furthermore, SFN treatment did not improve insulin level, and the insulin sensitizer hormone adiponectin as potential players for enhancing insulin sensitivity. 1. Axelsson AS, Tubbs E, Mecham B, Chacko S, Nenonen HA, Tang Y, et al. Sci Transl Med. 2017;9(394).

Characterization of insulin receptor kinase activity and autophosphorylation in different skeletal muscle types

1991 ◽  
Vol 260 (1) ◽  
pp. E1-E7 ◽  
Author(s):  
S. Azhar ◽  
J. C. Butte ◽  
R. F. Santos ◽  
C. E. Mondon ◽  
G. M. Reaven
Keyword(s):  
Skeletal Muscle ◽  
Insulin Sensitivity ◽  
Tyrosine Kinase ◽  
Insulin Receptor ◽  
Kinase Activity ◽  
Insulin Binding ◽  
Tyrosine Kinase Activity ◽  
Fiber Composition ◽  
Muscle Types ◽  
Skeletal Muscle Types

We have examined insulin binding, autophosphorylation, and tyrosine kinase activity in detergent-solubilized and wheat germ agglutinin-purified insulin receptor preparations from four rat muscles of different fiber composition (i.e., tensor fascia latae, soleus, vastus intermedius, and plantaris). Insulin binding activity was similar in three of the four muscles but lower in tensor fascia latae. No significant differences were noted in the affinity of insulin for its receptor from various muscle types. Insulin receptor tyrosine kinase activity measured in the absence (basal) and presence of insulin (0.3-300 nM) was comparable in all muscle types (normalized to the amount of insulin bound). Insulin sensitivity, measured as the dose of insulin required for half-maximal activation of kinase activity, was also similar in all muscle types. Likewise, incubation of receptor preparations with [gamma-32P]ATP, Mn2+, and insulin (0.25-100 nM) resulted in a dose-dependent autophosphorylation of the beta-subunit (relative molecular weight approximately 95 kDa) with similar kinetics in all muscle types. In conclusion, these results show that the functional behavior of the insulin receptor autophosphorylation-kinase system (in vitro) is not changed by alterations in muscle fiber composition, indicating that differences in insulin sensitivity between different skeletal muscle types is probably not due to modulation of the insulin receptor phosphorylation system.

EFFECT OF ENDOCRINE MANIPULATIONS ON GLUCOCORTICOID BINDING CAPACITY IN RAT SKELETAL MUSCLE

1978 ◽  
Vol 88 (1) ◽  
pp. 199-208 ◽  
Author(s):  
Michael Mayer ◽  
Fred Rosen
Keyword(s):  
Skeletal Muscle ◽  
Binding Sites ◽  
Binding Capacity ◽  
Specific Binding ◽  
Female Rats ◽  
Receptor Protein ◽  
Slight Reduction ◽  
Binding Assays ◽  
Receptor Concentration ◽  
Streptozotocin Induced Diabetes

ABSTRACT [3H]Dexamethasone binding capacity in rat muscle cytosol was determined after various endocrine manipulations in an attempt to identify factors which might regulate the level of the cytoplasmic hormone receptor protein. Hypophysectomy and adrenalectomy markedly increased the specific binding of [3H]dexamethasone in skeletal muscle cytosol, while implantation of the MtT tumour which secretes ACTH and growth hormone, as well as treatment with glucocorticoids reduced the glucocorticoid specific binding. Since the effects of hypophysectomy and the MtT tumour depend on the presence of the adrenals, they appear to be mediated via changes in circulating glucocorticoid level. Alloxan- or streptozotocin-induced diabetes caused only a slight reduction in the binding of [3H]dexamethasone in muscle, suggesting that the enhanced responsiveness to glucocorticoids in diabetes is not due to increased glucocorticoid receptor activity. There is a sex-dependent effect on binding, female rats having a higher concentration of binding sites. Furthermore, treatment with the synthetic androgen fluoxymesterone or with glucocorticoids reduces binding, while oestradiol-17β enhances it. The changes in glucocorticoid binding capacity induced by the various endocrine manipulations appear to reflect mainly changes in receptor concentration rather than occupancy, since the binding assays were preformed after a suitable time allowance for removal of the administered hormones by metabolism.

The in vitro effect of corticosterone on insulin binding and glucose metabolism in mouse skeletal muscles

1985 ◽  
Vol 63 (9) ◽  
pp. 1133-1138 ◽  
Author(s):  
M. H. Tan ◽  
A. Bonen
Keyword(s):  
Skeletal Muscle ◽  
Skeletal Muscles ◽  
Extensor Digitorum Longus ◽  
Insulin Binding ◽  
In Vivo Model ◽  
In Vitro System ◽  
Vitro Effect ◽  
Contralateral Muscle

We studied the in vitro effect of corticosterone on insulin binding, uptake of 2-deoxy-D-glucose, glycolysis, and glycogenesis in the soleus and extensor digitorum longus (EDL) of Swiss–Webster mice. In each experiment, one muscle (soleus/EDL) was incubated with corticosterone (0.1, 1, 50, and 100 μg/mL) and the respective contralateral muscle was incubated without corticosterone, but at the same insulin and pH levels. Corticosterone did not affect insulin binding in both muscles. However, corticosterone decreased the uptake of 2-deoxy-D-glucose and the rate of glycolysis and glycogenesis in both muscles when the dose was pharmacologic (50 and 100 μg/mL), but not when it was physiologic (0.1 and 1 μg/mL). For glycolysis and glycogenesis, the suppression was greater in the EDL when compared with the soleus. This suppression was seen in both basal and insulin-stimulated conditions. In this in vitro system, where the experimental muscle is not exposed to prior hyperinsulinemia as in the in vivo model, corticosterone, at pharmacologic doses, affects postreceptor events without altering the insulin binding in the skeletal muscle.

Capillary supply of skeletal muscles from acclimatized white-footed mice Peromyscus

1981 ◽  
Vol 241 (5) ◽  
pp. R357-R361
Author(s):  
S. J. Wickler
Keyword(s):  
Skeletal Muscle ◽  
Heat Production ◽  
Skeletal Muscles ◽  
Capillary Density ◽  
Area Index ◽  
Fiber Area ◽  
Hindlimb Muscles ◽  
The Mean ◽  
Thermogenic Capacity ◽  
Muscle Capillaries

Winter-acclimatized white-footed mice (Peromyscus leucopus) can increase their aerobic heat production under cold stress by 70%. The possibility that changes in microvascular supply might account, in part, for some of this increased thermogenic capacity was examined in one of the primary thermogenic tissues, skeletal muscle. Capillaries were stained histochemically in four hindlimb muscles of freshly captured Peromyscus in summer and winter. Capillary density, mean fiber area, and mean capillaries in contact per muscle fiber were obtained from the soleus, plantaris, gastrocnemius, and semitendinosus. If results from all individual muscles are combined, mean fiber area is significantly smaller (8%) and mean capillary density is significantly greater (40%) in winter muscles. The mean number of capillaries in contact is not different, but the mean ratio of capillaries in contact per mean fiber area (index of potential perfusion) is significantly greater (25%) in winter muscles.

Na+,K+-ATPase enzyme units in lean and obese (ob/ob) thyroxine-injected mice.

1979 ◽  
Vol 237 (3) ◽  
pp. E265
Author(s):  
M H Lin ◽  
J G Vander Tuig ◽  
D R Romsos ◽  
T Akera ◽  
G A Leveille
Keyword(s):  
Skeletal Muscle ◽  
Thyroid Hormone ◽  
Large Dose ◽  
Binding Sites ◽  
Hormone Treatment ◽  
Obese Mice ◽  
Ouabain Binding ◽  
Hindlimb Muscles

The possible involvement of Na+,K+-ATPase in the etiology of obesity in the obese (ob/ob) mouse was explored. The number of Na+,K+-ATPase enzyme units in skeletal muscle, liver, and kidneys from 4- and 8-wk-old obese and lean mice was estimated from saturable [3H]ouabain binding to particulate fractions. Neither phenotype nor age altered the Kd value for ouabain binding in these three tissue preparations. The total number of [3H]ouabain binding sites in hindlimb muscles was 35--55% lower in 4- and 8-wk-old obese mice than in their lean counterparts. However, the total number of [3H]ouabain binding sites in liver and kidneys of obese mice was similar to values observed in their lean counterparts. Because it has been suggested that ob/ob mice are hypothyroid, we investigated the response of Na+,K+-ATPase in these mice to thyroid hormone treatment (approximately 5 microgram thyroxine/day for 2 wk). The number of [3H]ouabain binding sites in the three tissues increased in both obese and lean mice injected with this relatively large dose of thyroxine, but the obese mice were 2--3 times more responsive than lean mice.

scholarly journals The long noncoding RNA MyHC IIA/X-AS contributes to skeletal muscle myogenesis and maintains the fast fiber phenotype

2020 ◽  
Vol 295 (15) ◽  
pp. 4937-4949 ◽  
Author(s):  
Mingle Dou ◽  
Ying Yao ◽  
Lu Ma ◽  
Xiaoyu Wang ◽  
Xin'e Shi ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Muscle Fiber ◽  
Long Noncoding Rna ◽  
Noncoding Rna ◽  
Skeletal Muscles ◽  
Fiber Type ◽  
Muscle Fiber Type ◽  
Fast Fiber ◽  
Slow Type ◽  
Myhc Expression

Mammalian skeletal muscles comprise different types of muscle fibers, and this muscle fiber heterogeneity is generally characterized by the expression of myosin heavy chain (MyHC) isoforms. A switch in MyHC expression leads to muscle fiber–type transition under various physiological and pathological conditions, but the underlying regulator coordinating the switch of MyHC expression remains largely unknown. Experiments reported in this study revealed the presence of a skeletal muscle–specific antisense transcript generated from the intergenic region between porcine MyHC IIa and IIx and is referred to here as MyHC IIA/X-AS. We found that MyHC IIA/X-AS is identified as a long noncoding RNA (lncRNA) that is strictly expressed in skeletal muscles and is predominantly distributed in the cytoplasm. Genetic analysis disclosed that MyHC IIA/X-AS stimulates cell cycle exit of skeletal satellite cells and their fusion into myotubes. Moreover, we observed that MyHC IIA/X-AS is more enriched in fast-twitch muscle and represses slow-type gene expression and thereby maintains the fast phenotype. Furthermore, we found that MyHC IIA/X-AS acts as a competing endogenous RNA that sponges microRNA-130b (miR-130b) and thereby maintains MyHC IIx expression and the fast fiber type. We also noted that miR-130b was proved to down-regulate MyHC IIx by directly targeting its 3′-UTR. Together, the results of our study uncovered a novel pathway, which revealed that lncRNA derived from the skeletal MyHC cluster could modulate local MyHC expression in trans, highlighting the role of lncRNAs in muscle fiber–type switching.

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