A β-hydroxybutyrate shunt pathway generates anti-obesity ketone metabolites
María Dolores Moya-Garzón, Mengjie Wang, Veronica L. Li, Xuchao Lyu, Wei Wei, Alan Sheng-Hwa Tung, Steffen H. Raun, Meng Zhao, Laetitia Coassolo, Hashim Islam, Bárbara Oliveira, Yuqin Dai, Jan Spaas, Antonio Delgado‐González, Kenyi Donoso, Aurora Alvarez‐Buylla, Francisco Franco-Montalbán, Anudari Letian, Catherine Ward, Lichao Liu, Katrin J. Svensson, Emily L. Goldberg, Christopher D. Gardner, Jonathan P. Little, Steven M. Banik, Yong Xu, Jonathan Z. Long
Abstract
β-Hydroxybutyrate (BHB) is an abundant ketone body. To date, all known pathways of BHB metabolism involve the interconversion of BHB and primary energy intermediates. Here, we identify a previously undescribed BHB secondary metabolic pathway via CNDP2-dependent enzymatic conjugation of BHB and free amino acids. This BHB shunt pathway generates a family of anti-obesity ketone metabolites, the BHB-amino acids. Genetic ablation of CNDP2 in mice eliminates tissue amino acid BHB-ylation activity and reduces BHB-amino acid levels. The most abundant BHB-amino acid, BHB-Phe, is a ketosis-inducible congener of Lac-Phe that activates hypothalamic and brainstem neurons and suppresses feeding. Conversely, CNDP2-KO mice exhibit increased food intake and body weight following exogenous ketone ester supplementation or a ketogenic diet. CNDP2-dependent amino acid BHB-ylation and BHB-amino acid metabolites are also conserved in humans. Therefore, enzymatic amino acid BHB-ylation defines a ketone shunt pathway and bioactive ketone metabolites linked to energy balance.