As
we all know, exercise is very important in our daily lives. It can help to
control weight, improve mood (through endorphins or stimulation of norepinephrine), boost energy,
promote better sleep, increase arousal, and more. However, a new study has
shown that exercise can also be advantageous to patients undergoing
chemotherapy.
While
the main concern of cancer patients is the cancer itself, they also have to
deal with the long-term increased risk of cardiovascular disease. Unfortunately,
as if patients with cancer didn’t have enough to worry about, negative cardiac
side effects are very common with doxorubicin (cancer drug to stop the growth
of cancer cells in the body which also has a side effect of weight gain,
however that is probably not the most concerning aspect for someone fighting
cancer). Researchers suspected that exercise could help protect heart cells
from the effects of doxorubicin. However, testing exercise along with
chemotherapy itself was not tested.
This
study consisted of four groups of mice (four groups were injected with melanoma
cells, two groups were given doxorubicin and the other two were injected with a
placebo, one group from the doxorubicin and one from the placebo group
exercised for 45 minutes a day/ 5days a week). While the original goal was to
determine if exercise helped with the heart affects, the results through echocardiogram and tissue analysis
showed “as expected, doxorubicin was found to reduce the heart's function and
size and increased fibrosis -- a damaging thickening of tissue. Mice that
exercised were not protected from this damage.” However, unexpectedly, the
tumor size was affected. The mice that exercised and received chemotherapy had
significantly smaller tumors than the mice that received only doxorubicin.
The
main thought for this finding was perhaps exercising increases blood flow to
the tumor, which brought more of the drug to it as well. The researchers concluded
that moving/exercising affects how drugs are metabolized, which calls for more
research in the specific processes. Either way, implications of this study open
the door to not only benefiting cancer patients, but also medication in general
in terms of dosage, negative side affects, and overall outcomes!
This is really interesting because I thought that increased blood flow to a tumor actually helps the tumor grow since more blood means more nutrients. It would be interesting to see if exercise also shrinks tumors found in other cancers besides melanoma. I was also surprised that the mice who were on the exercise regimen didn't exhibit any protection from doxorubicin caused heart issues. Do you think that a more vigorous exercise routine would help fight the doxorubicin effects on the heart or maybe even shrink the tumor even more? Do you think resistance training could also help decrease the tumor size?
ReplyDeletehttp://health.clevelandclinic.org/2014/03/study-vigorous-exercise-may-help-heart-failure/
http://www.unm.edu/~lkravitz/Article%20folder/resistben.html
Wow - Great article Nassim! In my undergrad, I helped on some research surrounding your article's main focus with the cardiotoxic effects of doxorubicin and how exercise can help to combat the effects, as seen in: Low intensity exercise training protects against doxorubicin cardiotoxicity. It is exciting to see how this research is continuing and that the medical community is adapting to these measures. Thanks for sharing!
ReplyDeletehttp://www.ncbi.nlm.nih.gov/pubmed/16210442
http://www.ncbi.nlm.nih.gov/pubmed/15845878