Research on brain regulation of appetite published in Neuron
Recent research from the lab of Qingchun Tong, PhD, professor and Cullen Chair in Molecular Medicine, studying how the brain regulates reduced appetite in response to environmental stress has been published in Neuron.
The article titled, “An excitatory projection from the basal forebrain to the ventral tegmental area that underlies anorexia-like phenotypes,” can be found here. Authors for the story include Jing Cai; Yanyan Jiang. PhD; Yuanzhong Xu, PhD; Zhiying Jiang, PhD; Claire Young; Hongli Li, PhD; Joshua Ortiz-Guzman, PhD; Yizhou Zhou, PhD; Yulong Li, PhD; Yong Xu, PhD; Benjamin R. Arenkiel, PhD; and Tong.
Using preclinical models, the lab used injections to deliver viral vectors carrying genes that express targeted proteins in specific brain regions. After the injections, the team used a combination of advanced CA2+ imaging to study how neurons respond to different cues in different physiological conditions, as well as various behavioral tests studying the outcomes of activation or inhibition of neuronal activities.
The data revealed that a contributing factor in the development of anorexia in humans could be a neuronal pathway involving reduced dopamine release. An overreaction of the pathway in models led to hypophagia and hyperactivity, which are the most representative features in human patients diagnosed with anorexia.
“We identified a neuronal pathway that is highly sensitive to environmental threat cues, reduces appetite, increases physical activity, and drives anxiety-like behaviors in preclinical models,” Cai said. “The phenotypes we observed resemble the typical symptoms of patients diagnosed with anorexia, which suggest that the abnormality of this neuronal pathway might contribute to the development of anorexia in humans.”
Using these results, the lab will now look into the detailed mechanisms of how neuronal pathways lead to reduced dopamine and the specific role dopamine plays in anorexia nervosa.
“Our results may have important implications in the understanding of neuronal mechanisms of anorexia nervosa and provide potential brain targets to study anorexia in humans,” Cai said. “In addition, the role of dopamine in feeding regulation is mysterious and poorly understood. Our results support the idea that dopamine is important for food motivation and energy drive.”
“We would like to thank everyone in the Tong Lab for their input to this body of work and our collaborators Benjamin Arenkiel from Baylor College for Medicine and Yulong Li, from Peking University, for their generous help,” Cai said. “We would also like to thank our committee members for their constructive suggestions during all committee meetings.”