Effects of Treadmill Exercise on p-AMPK, p-ACC and Malonyl-CoA Expression of Skeletal Muscle and Cardiac Muscle in Diabetic Rats

2016 ◽  
Vol 23 (2) ◽  
pp. 276
Author(s):  
Jin-Kyung Cho ◽  
Yong-Suk Ji ◽  
Kwang-Seok Hyun
Keyword(s):  
Skeletal Muscle ◽  
Cardiac Muscle ◽  
Treadmill Exercise ◽  
Diabetic Rats ◽  
Malonyl Coa

Inverse alterations of BCKA dehydrogenase activity in cardiac and skeletal muscles of diabetic rats

1999 ◽  
Vol 277 (4) ◽  
pp. E685-E692 ◽  
Author(s):  
Yolanda B. Lombardo ◽  
Cynthia Serdikoff ◽  
Manikkavasagar Thamotharan ◽  
Harbhajan S. Paul ◽  
Siamak A. Adibi
Keyword(s):  
Gene Expression ◽  
Skeletal Muscle ◽  
Protein Expression ◽  
Cardiac Muscle ◽  
Dehydrogenase Activity ◽  
Skeletal Muscles ◽  
Diabetic Rats ◽  
Gene Expressions ◽  
The Difference ◽  
Activity State

Rat cardiac and skeletal muscles, which have been used as model tissues for studies of regulation of branched-chain α-keto acid (BCKA) oxidation, vary greatly in the activity state of their BCKA dehydrogenase. In the present experiment, we have investigated whether they also vary in response of their BCKA dehydrogenase to a metabolic alteration such as diabetes and, if so, to investigate the mechanism that underlies the difference. Diabetes was produced by depriving streptozotocin-treated rats of insulin administration for 96 h. The investigation of BCKA dehydrogenase in the skeletal muscle (gastrocnemius) showed that diabetes 1) increased its activity, 2) increased the protein and gene expressions of all of its subunits (E1α, E1β, E2), 3) increased its activity state, 4) decreased the rate of its inactivation, and 5) decreased the protein expression of its associated kinase (BCKAD kinase) without affecting its gene expression. In sharp contrast, the investigation of BCKA dehydrogenase in the cardiac muscle showed that diabetes 1) decreased its activity, 2) had no effect on either protein or gene expression of any of its subunits, 3) decreased its activity state, 4) increased its rate of inactivation, and 5) increased both the protein and gene expressions of its associated kinase. In conclusion, our data suggest that, in diabetes, the protein expression of BCKAD kinase is downregulated posttranscriptionally in the skeletal muscle, whereas it is upregulated pretranslationally in the cardiac muscle, causing inverse alterations of BCKA dehydrogenase activity in these muscles.

Regulation of eukaryotic initiation factor-2B activity in muscle of diabetic rats

1993 ◽  
Vol 264 (1) ◽  
pp. E101-E108 ◽  
Author(s):  
A. M. Karinch ◽  
S. R. Kimball ◽  
T. C. Vary ◽  
L. S. Jefferson
Keyword(s):  
Skeletal Muscle ◽  
Protein Synthesis ◽  
Cardiac Muscle ◽  
Casein Kinase Ii ◽  
Diabetic Rats ◽  
Casein Kinase ◽  
Initiation Factor ◽  
Eukaryotic Initiation Factor ◽  
Fast Twitch

Peptide-chain initiation is inhibited in fast-twitch skeletal muscle, but not heart, of diabetic rats. We have investigated mechanisms that might maintain eukaryotic initiation factor (eIF)-2B activity, preventing loss of efficiency of protein synthesis in heart of diabetic rats but not in fast-twitch skeletal muscle. There was no change in the amount or phosphorylation state of eIF-2 in skeletal or cardiac muscle during diabetes. In contrast, eIF-2B activity was decreased in fast-twitch but not slow-twitch muscle from diabetic animals. NADP+ inhibited partially purified eIF-2B in vitro, but addition of equimolar NADPH reversed the inhibition. The NADPH-to-NADP+ ratio was unchanged in fast-twitch muscle after induction of diabetes but was increased in heart of diabetic rats, suggesting that NADPH also prevents inhibition of eIF-2B in vivo. The activity of casein kinase II, which can phosphorylate and activate eIF-2B in vitro, was significantly lower in extracts of fast-twitch, but not cardiac muscle, of diabetic rats compared with controls. The results presented here demonstrate that changes in eIF-2 alpha phosphorylation are not responsible for the effect of diabetes on eIF-2B activity in fast-twitch skeletal muscle. Modulation of casein kinase II activity may be a factor in the regulation of protein synthesis in muscle during acute diabetes. The activity of eIF-2B in heart might be maintained by the increased NADPH/NADP+.

Effects of dipyridamole on muscle blood flow in exercising miniature swine

1989 ◽  
Vol 257 (5) ◽  
pp. H1507-H1515 ◽  
Author(s):  
M. H. Laughlin ◽  
R. E. Klabunde ◽  
M. D. Delp ◽  
R. B. Armstrong
Keyword(s):  
Skeletal Muscle ◽  
Blood Flow ◽  
Cardiac Muscle ◽  
Respiratory Muscle ◽  
Maximal Exercise ◽  
Treadmill Exercise ◽  
Vo2 Max ◽  
Miniature Swine ◽  
Extensor Muscles ◽  
Vasodilator Reserve

The purpose of this study was to determine whether a vasodilator reserve exists in respiratory muscles and forelimb skeletal muscles in miniature swine during treadmill exercise. Blood flow (BF) was measured with radiolabeled microspheres during preexercise and before and after dipyridamole (DYP; 1 mg/kg iv) at 2 min of treadmill exercise at 11.2 (70% Vo2 max) and 17.6 km/h (Vo2 max). Muscle BFs were increased during exercise, and the relationship between exercise intensity and BF varied among the muscles. The high-oxidative extensor muscles and the flexor muscles attained peak BFs at 11.2 km/h, whereas the more superficial, lower oxidative extensor muscles showed increases in BF up to maximal exercise. During running at 11.2 km/h, DYP produced increases in BF only in cardiac muscle, respiratory muscle and the medial head of the triceps muscle (MHT), which is composed of 91% slow-twitch oxidative (SO) fibers. During maximal exercise (17.6 km/h), DYP produced a 31-mmHg decrease in mean arterial pressure (MAP) and increases in vascular conductance in all muscles studied. BF was only increased in MHT and cardiac muscle. We conclude that vasodilator reserve remains in skeletal muscle and respiratory muscle even during maximal exercise in swine. If it is assumed that DYP-induced vasodilation in a muscle sample is indicative of adenosine production, these results suggest that SO skeletal muscle (MHT) and respiratory muscle are similar to cardiac muscle in that they produce adenosine even when adequately perfused. Furthermore, during maximal exercise, all skeletal muscle appears to produce adenosine, suggesting that muscle BF is restricted under these conditions.(ABSTRACT TRUNCATED AT 250 WORDS)

Alterations in levels of Na(+)-K(+)-ATPase isoforms in heart, skeletal muscle, and kidney of diabetic rats

1993 ◽  
Vol 265 (2) ◽  
pp. E243-E251 ◽  
Author(s):  
Y. C. Ng ◽  
P. H. Tolerico ◽  
C. B. Book
Keyword(s):  
Skeletal Muscle ◽  
Atpase Activity ◽  
Cardiac Muscle ◽  
Insulin Treatment ◽  
Marked Decrease ◽  
Diabetic Rats ◽  
Cellular Mechanisms ◽  
Atpase Subunit ◽  
Subunit Isoforms ◽  
Specific Regulation

In streptozotocin (STZ)-induced diabetic rats, activities of Na(+)-K(+)-ATPase and the Na pump have been shown to be altered. Cellular mechanisms underlying such changes remain unclear. The present studies examined by immunoblotting the levels of Na(+)-K(+)-ATPase subunit isoforms in heart, skeletal muscle, and kidney of diabetic rats. Effects of insulin treatment on these levels were also studied. In cardiac muscle, STZ-induced diabetes caused a marked decrease in alpha 2-levels, a moderate decrease in beta 1-levels, and no significant change in alpha 1-levels. Corresponding to these changes, Na(+)-K(+)-ATPase activity, estimated by K(+)-dependent p-nitrophenylphosphatase activity, also decreased. By contrast, there were significant increases in alpha 1- and alpha 2-levels in skeletal muscle and in alpha 1- and beta 1-levels in kidneys of diabetic rats. There was also a detectable, but not significant, increase in beta 1-levels in diabetic skeletal muscle. In kidney, the increase in subunit levels was associated with significantly increased Na(+)-K(+)-ATPase activity, whereas, in skeletal muscle, no increase in enzyme activity was observed. In diabetic rats, 7 days of insulin treatment (10 U/kg sc) partially reversed the decreased alpha 2- and beta 1-levels in diabetic cardiac muscle, without significant effect on alpha 1-levels. In skeletal muscle, insulin treatment also partially reversed the elevated alpha 1- and alpha 2-levels but was without significant effect on beta 1-levels. It is concluded that STZ-induced diabetes exerted isoform- and tissue-specific regulation of the Na(+)-K(+)-ATPase subunit isoforms.(ABSTRACT TRUNCATED AT 250 WORDS)

Malonyl-CoA in Skeletal Muscle and Liver of Streptozotocin-Diabetic Rats

1991 ◽  
Vol 198 (1) ◽  
pp. 569-571 ◽  
Author(s):  
I. M. Elayan ◽  
D. C. Cartmill ◽  
C. B. Eckersell ◽  
J. Wilkin ◽  
W. W. Winder
Keyword(s):  
Skeletal Muscle ◽  
Diabetic Rats ◽  
Malonyl Coa ◽  
Streptozotocin Diabetic Rats

Indirect effect of catecholamines on development of insulin resistance in skeletal muscle from diabetic rats

Diabetes ◽  
1989 ◽  
Vol 38 (7) ◽  
pp. 906-910 ◽  
Author(s):  
M. Bostrom ◽  
Z. Nie ◽  
G. Goertz ◽  
J. Henriksson ◽  
H. Wallberg-Henriksson
Keyword(s):  
Insulin Resistance ◽  
Skeletal Muscle ◽  
Indirect Effect ◽  
Diabetic Rats

Skeletal and cardiac muscle protein turnover during cold acclimation in young rats

2000 ◽  
Vol 278 (3) ◽  
pp. R705-R711 ◽  
Author(s):  
T. A. McAllister ◽  
J. R. Thompson ◽  
S. E. Samuels
Keyword(s):  
Skeletal Muscle ◽  
Protein Synthesis ◽  
Cardiac Muscle ◽  
Cold Acclimation ◽  
Protein Turnover ◽  
Muscle Protein ◽  
Muscle Protein Turnover ◽  
Protein Mass ◽  
The Absolute

The effect of long-term cold exposure on skeletal and cardiac muscle protein turnover was investigated in young growing animals. Two groups of 36 male 28-day-old rats were maintained at either 5°C (cold) or 25°C (control). Rates of protein synthesis and degradation were measured in vivo on days 5, 10, 15, and 20. Protein mass by day 20 was ∼28% lower in skeletal muscle (gastrocnemius and soleus) and ∼24% higher in heart in cold compared with control rats ( P < 0.05). In skeletal muscle, the fractional rates of protein synthesis ( k syn) and degradation ( k deg) were not significantly different between cold and control rats, although k syn was lower (approximately −26%) in cold rats on day 5; consequent to the lower protein mass, the absolute rates of protein synthesis (approximately −21%; P < 0.05) and degradation (approximately −13%; P < 0.1) were lower in cold compared with control rats. In heart, overall, k syn(approximately +12%; P < 0.1) and k deg(approximately +22%; P < 0.05) were higher in cold compared with control rats; consequently, the absolute rates of synthesis (approximately +44%) and degradation (approximately +54%) were higher in cold compared with control rats ( P < 0.05). Plasma triiodothyronine concentration was higher ( P < 0.05) in cold compared with control rats. These data indicate that long-term cold acclimation in skeletal muscle is associated with the establishment of a new homeostasis in protein turnover with decreased protein mass and normal fractional rates of protein turnover. In heart, unlike skeletal muscle, rates of protein turnover did not appear to immediately return to normal as increased rates of protein turnover were observed beyond day 5. These data also indicate that increased rates of protein turnover in skeletal muscle are unlikely to contribute to increased metabolic heat production during cold acclimation.

Sign in / Sign up

Export Citation Format

Share Document