Mitochondrial apoptotic signaling is elevated in cardiac but not skeletal muscle in the obese Zucker rat and is reduced with aerobic exercise

Jonathan M. Peterson, Randall W. Bryner, Amy Sindler, Jefferson C. Frisbee, Stephen Alway

Research output: Contribution to journalArticle

31 Citations (Scopus)

Abstract

Mitochondrial apoptosis and apoptotic signaling modulations by aerobic training were studied in cardiac and skeletal muscles of obese Zucker rats (OZR), a rodent model of metabolic syndrome. Comparisons were made between left ventricle, soleus, and gastrocnemius muscles from OZR (n = 16) and aged-matched lean Zucker rats (LZR; n = 16) that were untrained (n = 8) or aerobically trained on a treadmill for 9 wk (n = 8). Cardiac Bcl-2 protein expression levels were ∼50% lower in the OZR compared with the LZR, with no difference in either of the skeletal muscles. Bax protein expression levels were similar in skeletal muscles of the OZR compared with the LZR. Furthermore, mitochondrial apoptotic signaling was not different in skeletal muscles of OZR and LZR groups. However, there was an approximate sevenfold increase in the Bax protein accumulation in the myocardial mitochondrial-rich protein fraction of the OZR compared with the LZR. Additionally, there was an increase in cytosolic cytochrome c released from the mitochondria, caspase-9 and caspase-3 activity, with a corresponding elevation in DNA fragmentation in the cardiac muscles of the OZR compared with the LZR. Exercise training reduced cardiac Bax protein levels, the mitochondrial localization of Bax, cytosolic cytochrome c, caspase activity, and DNA fragmentation in cardiac muscles of the OZR after exercise, with no change in the skeletal muscles. These data show that mitochondrial apoptosis is elevated in the cardiac but not skeletal muscles of the OZR, but aerobic exercise training was effective in reducing cardiac mitochondrial apoptotic signaling.

Original languageEnglish (US)
Pages (from-to)1934-1943
Number of pages10
JournalJournal of applied physiology
Volume105
Issue number6
DOIs
StatePublished - Dec 1 2008
Externally publishedYes

Fingerprint

Zucker Rats
Skeletal Muscle
Exercise
bcl-2-Associated X Protein
Myocardium
DNA Fragmentation
Cytochromes c
Apoptosis
Caspase 9
Mitochondrial Proteins
Caspases
Caspase 3
Heart Ventricles
Rodentia
Mitochondria

All Science Journal Classification (ASJC) codes

  • Physiology
  • Physiology (medical)

Cite this

Mitochondrial apoptotic signaling is elevated in cardiac but not skeletal muscle in the obese Zucker rat and is reduced with aerobic exercise. / Peterson, Jonathan M.; Bryner, Randall W.; Sindler, Amy; Frisbee, Jefferson C.; Alway, Stephen.

In: Journal of applied physiology, Vol. 105, No. 6, 01.12.2008, p. 1934-1943.

Research output: Contribution to journalArticle

Peterson, Jonathan M. ; Bryner, Randall W. ; Sindler, Amy ; Frisbee, Jefferson C. ; Alway, Stephen. / Mitochondrial apoptotic signaling is elevated in cardiac but not skeletal muscle in the obese Zucker rat and is reduced with aerobic exercise. In: Journal of applied physiology. 2008 ; Vol. 105, No. 6. pp. 1934-1943.
@article{349d31338a2d4e04b424ca61db2fc670,
title = "Mitochondrial apoptotic signaling is elevated in cardiac but not skeletal muscle in the obese Zucker rat and is reduced with aerobic exercise",
abstract = "Mitochondrial apoptosis and apoptotic signaling modulations by aerobic training were studied in cardiac and skeletal muscles of obese Zucker rats (OZR), a rodent model of metabolic syndrome. Comparisons were made between left ventricle, soleus, and gastrocnemius muscles from OZR (n = 16) and aged-matched lean Zucker rats (LZR; n = 16) that were untrained (n = 8) or aerobically trained on a treadmill for 9 wk (n = 8). Cardiac Bcl-2 protein expression levels were ∼50{\%} lower in the OZR compared with the LZR, with no difference in either of the skeletal muscles. Bax protein expression levels were similar in skeletal muscles of the OZR compared with the LZR. Furthermore, mitochondrial apoptotic signaling was not different in skeletal muscles of OZR and LZR groups. However, there was an approximate sevenfold increase in the Bax protein accumulation in the myocardial mitochondrial-rich protein fraction of the OZR compared with the LZR. Additionally, there was an increase in cytosolic cytochrome c released from the mitochondria, caspase-9 and caspase-3 activity, with a corresponding elevation in DNA fragmentation in the cardiac muscles of the OZR compared with the LZR. Exercise training reduced cardiac Bax protein levels, the mitochondrial localization of Bax, cytosolic cytochrome c, caspase activity, and DNA fragmentation in cardiac muscles of the OZR after exercise, with no change in the skeletal muscles. These data show that mitochondrial apoptosis is elevated in the cardiac but not skeletal muscles of the OZR, but aerobic exercise training was effective in reducing cardiac mitochondrial apoptotic signaling.",
author = "Peterson, {Jonathan M.} and Bryner, {Randall W.} and Amy Sindler and Frisbee, {Jefferson C.} and Stephen Alway",
year = "2008",
month = "12",
day = "1",
doi = "10.1152/japplphysiol.00037.2008",
language = "English (US)",
volume = "105",
pages = "1934--1943",
journal = "Journal of Applied Physiology",
issn = "8750-7587",
publisher = "American Physiological Society",
number = "6",

}

TY - JOUR

T1 - Mitochondrial apoptotic signaling is elevated in cardiac but not skeletal muscle in the obese Zucker rat and is reduced with aerobic exercise

AU - Peterson, Jonathan M.

AU - Bryner, Randall W.

AU - Sindler, Amy

AU - Frisbee, Jefferson C.

AU - Alway, Stephen

PY - 2008/12/1

Y1 - 2008/12/1

N2 - Mitochondrial apoptosis and apoptotic signaling modulations by aerobic training were studied in cardiac and skeletal muscles of obese Zucker rats (OZR), a rodent model of metabolic syndrome. Comparisons were made between left ventricle, soleus, and gastrocnemius muscles from OZR (n = 16) and aged-matched lean Zucker rats (LZR; n = 16) that were untrained (n = 8) or aerobically trained on a treadmill for 9 wk (n = 8). Cardiac Bcl-2 protein expression levels were ∼50% lower in the OZR compared with the LZR, with no difference in either of the skeletal muscles. Bax protein expression levels were similar in skeletal muscles of the OZR compared with the LZR. Furthermore, mitochondrial apoptotic signaling was not different in skeletal muscles of OZR and LZR groups. However, there was an approximate sevenfold increase in the Bax protein accumulation in the myocardial mitochondrial-rich protein fraction of the OZR compared with the LZR. Additionally, there was an increase in cytosolic cytochrome c released from the mitochondria, caspase-9 and caspase-3 activity, with a corresponding elevation in DNA fragmentation in the cardiac muscles of the OZR compared with the LZR. Exercise training reduced cardiac Bax protein levels, the mitochondrial localization of Bax, cytosolic cytochrome c, caspase activity, and DNA fragmentation in cardiac muscles of the OZR after exercise, with no change in the skeletal muscles. These data show that mitochondrial apoptosis is elevated in the cardiac but not skeletal muscles of the OZR, but aerobic exercise training was effective in reducing cardiac mitochondrial apoptotic signaling.

AB - Mitochondrial apoptosis and apoptotic signaling modulations by aerobic training were studied in cardiac and skeletal muscles of obese Zucker rats (OZR), a rodent model of metabolic syndrome. Comparisons were made between left ventricle, soleus, and gastrocnemius muscles from OZR (n = 16) and aged-matched lean Zucker rats (LZR; n = 16) that were untrained (n = 8) or aerobically trained on a treadmill for 9 wk (n = 8). Cardiac Bcl-2 protein expression levels were ∼50% lower in the OZR compared with the LZR, with no difference in either of the skeletal muscles. Bax protein expression levels were similar in skeletal muscles of the OZR compared with the LZR. Furthermore, mitochondrial apoptotic signaling was not different in skeletal muscles of OZR and LZR groups. However, there was an approximate sevenfold increase in the Bax protein accumulation in the myocardial mitochondrial-rich protein fraction of the OZR compared with the LZR. Additionally, there was an increase in cytosolic cytochrome c released from the mitochondria, caspase-9 and caspase-3 activity, with a corresponding elevation in DNA fragmentation in the cardiac muscles of the OZR compared with the LZR. Exercise training reduced cardiac Bax protein levels, the mitochondrial localization of Bax, cytosolic cytochrome c, caspase activity, and DNA fragmentation in cardiac muscles of the OZR after exercise, with no change in the skeletal muscles. These data show that mitochondrial apoptosis is elevated in the cardiac but not skeletal muscles of the OZR, but aerobic exercise training was effective in reducing cardiac mitochondrial apoptotic signaling.

UR - http://www.scopus.com/inward/record.url?scp=57349129372&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=57349129372&partnerID=8YFLogxK

U2 - 10.1152/japplphysiol.00037.2008

DO - 10.1152/japplphysiol.00037.2008

M3 - Article

VL - 105

SP - 1934

EP - 1943

JO - Journal of Applied Physiology

JF - Journal of Applied Physiology

SN - 8750-7587

IS - 6

ER -