Altered cardiac muscle mTOR regulation during the progression of cancer cachexia in the ApcMin/+ mouse

  • Authors:
    • Nandini D.P.K. Manne
    • M. Lima
    • R. T. Enos
    • P. Wehner
    • J. A. Carson
    • Eric Blough
  • View Affiliations

  • Published online on: April 11, 2013     https://doi.org/10.3892/ijo.2013.1893
  • Pages: 2134-2140
Metrics: Total Views: 0 (Spandidos Publications: | PMC Statistics: )
Total PDF Downloads: 0 (Spandidos Publications: | PMC Statistics: )


Abstract

Cancer cachexia is a muscle wasting condition that occurs in response to a malignant growth in the body. The mechanisms regulating cardiac muscle mass with cachexia are not well understood. Using the ApcMin/+ mouse model of colorectal cancer, we investigated how cachexia affects the regulation of 5'-adenosine monophosphate-activated protein kinase (AMPK), protein kinase B (Akt) and mammalian target of rapamycin (mTOR) signaling in the heart. Compared to age-matched C57BL/6 (BL6) mice, ApcMin/+ body mass and heart mass were lower at 12 (11±5 and 8±3%, respectively) and 20 weeks (26±3 and 6±4%, respectively) of age (P<0.05). Diminished heart mass in the 20-week-old ApcMin/+ mice coincided with a decreased rate of myofibrillar protein synthesis and increased AMPKα phosphorylation. Cachexia decreased mTOR phosphorylation and the phosphorylation of the mTOR substrates, S6 ribosomal protein and 4EBP1 independent of Akt activation. These changes in mTOR-related protein signaling were accompanied by modest increases in the amount of Beclin1 but not protein ubiquitination or cardiomyocyte apoptosis. Taken together, these data suggest that loss of cardiac mass during cachexia progression in the ApcMin/+ mouse is associated with an Akt-independent suppression of anabolic signaling and evidence of increased autophagy.
View Figures
View References

Related Articles

Journal Cover

June 2013
Volume 42 Issue 6

Print ISSN: 1019-6439
Online ISSN:1791-2423

Sign up for eToc alerts

Recommend to Library

Copy and paste a formatted citation
x
Spandidos Publications style
Manne ND, Lima M, Enos RT, Wehner P, Carson JA and Blough E: Altered cardiac muscle mTOR regulation during the progression of cancer cachexia in the ApcMin/+ mouse. Int J Oncol 42: 2134-2140, 2013
APA
Manne, N.D., Lima, M., Enos, R.T., Wehner, P., Carson, J.A., & Blough, E. (2013). Altered cardiac muscle mTOR regulation during the progression of cancer cachexia in the ApcMin/+ mouse. International Journal of Oncology, 42, 2134-2140. https://doi.org/10.3892/ijo.2013.1893
MLA
Manne, N. D., Lima, M., Enos, R. T., Wehner, P., Carson, J. A., Blough, E."Altered cardiac muscle mTOR regulation during the progression of cancer cachexia in the ApcMin/+ mouse". International Journal of Oncology 42.6 (2013): 2134-2140.
Chicago
Manne, N. D., Lima, M., Enos, R. T., Wehner, P., Carson, J. A., Blough, E."Altered cardiac muscle mTOR regulation during the progression of cancer cachexia in the ApcMin/+ mouse". International Journal of Oncology 42, no. 6 (2013): 2134-2140. https://doi.org/10.3892/ijo.2013.1893