Decreasing body weight via temporary ablation of the sense of smell
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Shubhankar KulkarniAug 19, 2020
A large number of strategies are being used and developed for weight loss. A study measured the effect of ablating the mature olfactory sensory neurons in adult mice on energy homeostasis. These hyposmic (reduced ability to smell) mice exhibited normal food intake and body weight on a regular diet, but were resistant to obesity caused by a high-fat diet. The authors found out that this resistance was due to both reduced high-fat food intake and increased energy expenditure. They also found improved fat mass and reduction in insulin resistance in these mice. It was demonstrated that this increased energy expenditure was due to an increase in the activity of the brown adipose tissue. Sympathetic nerve activity and β-adrenergic receptors on white and brown adipocytes were stimulated to promote lipolysis. The authors generated mice with enhanced smelling ability by ablating the insulin-like growth factor 1 receptor on the olfactory sensory neurons. These mice exhibited increased body weight without any changes in food intake. Thus, the olfactory system can regulate body weight via changes in energy expenditure.
There definitely are differences between the olfactory system of mice and humans. However, temporary ablation or desensitization of the olfactory sensory neurons seems like a promising strategy to decrease body weight in humans.
Riera CE, Tsaousidou E, Halloran J, Follett P, Hahn O, Pereira MMA, et al. The Sense of Smell Impacts Metabolic Health and Obesity. Cell Metab [Internet]. 2017 Jul;26(1):198-211.e5. Available from: https://linkinghub.elsevier.com/retrieve/pii/S1550413117303571