Date of Award


Document Type


Degree Name

Master of Science (MS)

Legacy Department

Biological Sciences

Committee Chair/Advisor

Bain, Lisa J

Committee Member

Baldwin , William

Committee Member

Blob , Richard


A number of epidemiological studies have correlated arsenic exposurwith cancer, skin diseases, cardiovascular diseases, and adverse developmental outcomes such as stillbirths, spontaneous abortions, neonatal mortality, low birth weight, and delays in the use of musculature. The current study used C2C12 mouse myoblast cells to examine whether low concentrations of arsenic could alter their differentiation into myotubes, which would indicate that arsenic has the ability to act as a developmental toxicant. Myoblast cells were exposed to 20nM sodium arsenite and allowed to differentiate into myotubes and expression of the muscle-specific transcription factor myogenin, along with the expression of myosin light chain 2, and tropomyosin were investigated using real time PCR and immunofluorescence. Exposing C2C12 cells to 20nM sodium arsenite delayed the differentiation process, as evidenced by a significant reduction in the number of multinucleated myotubes. Additionally, arsenic exposure caused a time-dependant decrease in myogenin mRNA expression, as compared to the control cells, starting on day two of the differentiation process. Arsenic reduced myogenin mRNA levels by 1.4-fold on day two, 2.7-fold on day three, and 5.1-fold on day four of differentiation. This reduction in transcript number was confirmed by immunofluorescence, which also showed a decrease in the total number of nuclei expressing myogenin protein. Interestingly, myosin light chain 2 mRNA was significantly upregulated in the arsenic-exposed cells, although this did not translate into altered protein expression. This study demonstrated that low concentrations of arsenic are able to disturb the differentiation process of myoblasts without causing overt toxicity.



To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.