Q. Most of our readers have taken an interest in smell training as a therapy to help them improve their sense of smell after smell loss. As a cell biologist, what message do you have for our readers about smell training and its role in helping those with smell dysfunction?
A. I think that the most important message is that smell training is not a far-fetched notion. It is based on years of learning how the olfactory and nervous systems work, and
specifically, how nerve cells — and especially olfactory nerve cells — are generated or
maintained. Our understanding of smell training is also based on our understanding of how the brain makes new connections and reinforces existing connections. We know that using a neural pathway reinforces and strengthens that pathway. And so, not only is smell training helping the olfactory receptor cells, but it also is helping to create pathways in the brain that will be better able to receive, interpret and remember the information that it is getting.
Q. How far do you think this field has come in the last ten years? Can you describe how recent research has brought on our understanding of this field?
A. I think the progress has been exponential over the last ten years. I recently returned to
Monell after moving away ten years ago and it’s interesting to see the state of the science now vs then. We have technologies today that enable us to create animal models and cell culture models that allow us to trace individual olfactory cells as they are going through different stages of development. We can look at the entire molecular machinery in one shot, from individual cells or tissues or organs, and this technology is allowing us to ask questions that we couldn’t even think about asking ten years ago. That is really what is driving the progress.
Q. Some people are sceptical about the use of animal models such as mice to understand the biological processes in humans behind something like the sense of smell. How would you respond to someone who says “how is research on mice, and their sense of smell, applicable to humans?”
A. There are differences for sure. I have worked in comparative biology and anatomy and
am always tuned into the differences between humans and the animals we research. But there are also general principles. Biology is very good at adapting, designing, developing and using the most effective process or approach to doing something. And once it figures something out, it’s not going to discard it unless it has to. But there certainly are differences. Also, you can’t do certain experiments with people that you can do with animals, so we never are going to be able to replace the animal model. We are going to be able to improve our use of animal models though, and understand where the differences are and how to leverage the animal models in a way that tells us more about the human systems.
Q Looking to the future, what do you think is the most promising area of research for
olfactory dysfunction in the next few years?
A. Well I think there are two areas. One of them is going to be prevention, particularly with respect to age-related smell loss. We also want to find out what kind of early interventions may be helpful to prevent loss in other situations, whether through injury or an infection. I think in order for these things to happen, there is education that needs to be done within the medical community. Doctors just don’t think about sense of smell sometimes, and many people don’t either. In the example of a patient who has a traumatic brain injury, there will be other consequences at the forefront of treatment. With a patient with post-viral loss, earlier intervention could prevent or reduce olfactory loss. It is always easier to prevent something than to cure it. The second one is understanding how to help our sensory systems regenerate throughout life when there has been more damage than smell training can overcome. Whether this will come through stem cell replacement or activating the cells that remain to multiply, develop and mature remains to be seen, but we have the tools to do the work needed, if we have the financial backing that allows us to do so.
Q. If you had unlimited funding, and were asked to research something that would benefit people with olfactory loss, where would you put your new research money?
A. That’s a hard question. I have two answers. The first one is not research per se. It’s
scientific training. We need more people trained in multi-disciplinary and team-oriented
research. cross-disciplinary and multi-disciplinary trained people. And iIt would be great to create some sort of consortium where we could connect with people doing stem cell
research in other fields like vision, neurodegenerative or spinal cord research. And there
are even people looking at this from the dental perspective, for gum regeneration. If we
could bring people studying those kinds of challenges into olfaction, giant steps could be made. As for the research, attacking the most fundamental question of how olfactory stem cells turn into true, fully functional and integrated olfactory receptor neurons is the only way we will really get to a cure. We haven’t fully succeeded in this approach in any field yet, although pancreatic cell replacements are promising. So it isn’t going to be quick, or easy, but what we learn along the way will also direct us to new therapeutic approaches that may aid recovery incrementally.
Q Do you have anything else to add?
A. Go forth and smell!