image: Heath Schmidt, PhD, the Killebrew-Censits Chair of Undergraduate Education and a Professor of Neuroscience and Pharmacology in the Department of Biobehavioral Health Sciences
Credit: Penn Nursing
PHILADELPHIA (February 26, 2025) – Imagine a future where the grip of cocaine use disorder can be loosened, where cravings fade, and the risk of relapse diminishes. A new study published in Science Advances, led by Penn Nursing’s Heath Schmidt, PhD, brings this vision closer to reality. The research has identified a critical brain circuit that plays a pivotal role in regulating cocaine-seeking behavior.
Cocaine use disorder casts a long shadow, trapping individuals in a cycle of dependence and leaving limited options for effective treatment. This study delves deep into the brain, offering crucial insights into the underlying mechanisms of this complex disorder. By understanding how this intricate circuitry functions, scientists can pave the way for the development of more effective therapies, offering new hope to those struggling with this debilitating disorder.
At the heart of this discovery lies the role of glucagon-like peptide-1 (GLP-1), a hormone known for its involvement in regulating food intake and blood sugar. The study reveals that chronic cocaine use is associated with reduced GLP-1 levels, effects that suggest that increasing central GLP-1 signaling could reduce cocaine seeking.
Further investigation pinpointed a specific brain circuit: GLP-1-producing neurons in the nucleus tractus solitarius (NTS) that project to the ventral tegmental area (VTA), a key brain region involved in reward and motivation. By manipulating this circuit, researchers were able to significantly reduce cocaine-seeking behavior in animal models.
The study also sheds light on the specific cells involved. GLP-1 receptors were found to be primarily located on GABA neurons within the VTA. GABA, an inhibitory neurotransmitter, plays a crucial role in regulating brain activity. Importantly, activating these GLP-1 receptors increases the activity of GABA neurons, which in turn reduces the activity of dopamine neurons, a key neurotransmitter involved in reward and addiction.
"This research provides exciting new insights into the brain mechanisms underlying cocaine seeking," said Schmidt, the Killebrew-Censits Chair of Undergraduate Education and a Professor of Neuroscience and Pharmacology in the Department of Biobehavioral Health Sciences. "By understanding how GLP-1 signaling influences brain activity in this context, we can potentially develop new GLP-1-based treatments to treat cocaine use disorder."
This research opens a new chapter in the fight against cocaine use disorder. The findings offer a promising avenue for developing innovative therapies that target this critical brain circuit, potentially offering a lifeline to individuals struggling to break free from the grip of this devastating disorder.
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About the University of Pennsylvania School of Nursing
The University of Pennsylvania School of Nursing is one of the world’s leading schools of nursing. For the ninth year in a row, it is ranked the #1 nursing school in the world by QS University. Our Bachelor of Science in Nursing (BSN) is among the top ranked programs in the nation according to the 2025 U.S. News & World Report’s Best Colleges rankings. Our School also consistently ranks highly in the U.S. News & World Report annual list of best graduate schools and is ranked as one of the top schools of nursing in funding from the National Institutes of Health. Penn Nursing prepares nurse scientists and nurse leaders to meet the health needs of a global society through innovation in research, education, and practice. Follow Penn Nursing on: Facebook, X, LinkedIn, YouTube, & Instagram.
Journal
Science Advances
Article Title
An endogenous GLP-1 circuit engages VTA GABA neurons to regulate mesolimbic dopamine neurons and attenuate cocaine seeking
Article Publication Date
26-Feb-2025