Download Hair Cell Fact Sheet

Hair Cell Fact Sheet. A. Hussain, U. Hammoud, T. Sultan
Yamasoba, T., Kondo, K.
Supporting cell proliferation after hair cell injury in mature guinea pig cochlea in vivo.
Cell Tissue Research (2006) 325: 23–3.
Interesting fact that we learned:
After reading the article the interesting facts that we learned that there is potential for re-growth in hair cell
regeneration within a damaged cochlea. This provides light and further research into auditory studies for
people who have a hearing loss.
This study had two objectives - The first was to assess cell proliferation in the organ of corti of the cochlea,
following hair cell trauma. The second objective was to identify the type of cells that were labeled by the
BrdU, and if located to determine when they occur and how long they survive.
Hypothesis Tested:
The author’s hypothesized that dieter cells in the mature mammalian cochlea maintain a limited competence
to re-enter the cell cycle and proliferate after hair cell injury.
Methods:
The authors used 120 albino guinea pigs with a normal auditory response to assess cell proliferation in the
organ of corti after hair cell injury. A set of control guinea pigs with normal hearing were used in comparison
to deafened guinea pigs. The cochlea of deafened guinea pigs were ototoxically damaged and the organ of
corti cells were labeled with BrdU and examined using TEM. The guinea pigs auditory responses were
measured 3 days prior to the experiment and 3 days after. The normal organ of corti cells in undeafened
animals underwent the same procedure to act as the control.
Flaws include nonspecific uptake of BrdU in cells with damaged DNA. Furthermore, the BrdU staining is
effective up until 2 hours of staining and due to ethical restrictions they could only administer the stain every
12 hours.
The author’s methods appear to be valid based on the experimental procedure. The BrdU is effective in
staining proliferating cells that they wanted to observe. Validation of the experiment also comes from the
usage of a control group.
Results:
The results led the authors to accept the hypothesis. The experimental evidence presented by the authors
showed that the hair cell proliferation becomes limited in the cochlea and vestibular organs upon exposure to
ototoxins. The authors were successful in locating BrdU labeled cells in the organ of corti after the cells had
been exposed to ototoxins in order to track any proliferation. By tracking the BrdU labeled dieter cells they
concluded that these cells were capable of limited competence and further re-enter cell cycle even after being
damaged by ototoxin.
Discussion:
The author effectively analyzed the results and was able to formulate an accurate interpretation of the data.
The discussion was not redundant with the results and was helpful in interpreting them. Various short
comings of the research were addressed in the discussion section with possible improvements for future
research. The authors concluded that supporting cell proliferation was possible even after damage to hair cells
and supported their hypothesis well with the results obtained by various experiments they conducted.
The abstract gave a brief and general understanding of the whole study. The author’s summarized
their experimental results which accurately complemented the study. Most of the details important to
the body of the article were touched upon within the abstract.
Opinion of Paper:
Our opinion of the paper was that the study was well thought out and organized. Their discussion was concise
and helps a reader with less knowledge to properly understand their intentions towards their research. The
paper lends support to future research in hair re-growth and regeneration, specifically to the hair cells in the
ear.