{"id":"491b31be-2116-504d-8621-f185ed90cbb6","stable_key":"c9aa15a1-8ba2-5913-b2dd-372af304bf87:fast-bhb-hcar2","predicate":"activates","statement":"D-beta-hydroxybutyrate activated human HM74a/HCAR2 and its mouse orthologue.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"6c7473af-5b87-5315-8e84-425f9bae232e","mechanism_event_label":"A fasting-associated ketone uses a receptor also used by nicotinic acid.","subject":{"id":"59496369-eea6-5302-a0a3-2dcfa8f2b71a","slug":"d-beta-hydroxybutyrate","display_name":"D-(R)-beta-hydroxybutyrate","entity_type_key":"small_molecule"},"object":{"id":"c31b5501-5abf-57bb-8324-15923ed678cf","slug":"hcar2","display_name":"Human hydroxycarboxylic acid receptor 2 / HCAR2","entity_type_key":"protein"},"evidence_count":1,"mechanism_event":{"id":"6c7473af-5b87-5315-8e84-425f9bae232e","stable_key":"c9aa15a1-8ba2-5913-b2dd-372af304bf87:fast-bhb-hcar2-event","event_type":"observed_relationship","label":"A fasting-associated ketone uses a receptor also used by nicotinic acid.","description":"D-beta-hydroxybutyrate activated human HM74a/HCAR2 and its mouse orthologue.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"59496369-eea6-5302-a0a3-2dcfa8f2b71a","slug":"d-beta-hydroxybutyrate","display_name":"D-(R)-beta-hydroxybutyrate","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"c31b5501-5abf-57bb-8324-15923ed678cf","slug":"hcar2","display_name":"Human hydroxycarboxylic acid receptor 2 / HCAR2","entity_type_key":"protein"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"c9d27457-988d-5d60-bba4-44e320789996","slug":"mouse-hcar2","display_name":"Mouse Hcar2 / PUMA-G receptor","entity_type_key":"protein"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""}]},"contexts":[{"dimension":"evidence_access","value_text":"Primary abstract","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Human and mouse receptor pharmacology.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Shared receptor does not imply identical exposures or clinical effects.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Fasting physiological-state collection; human protocols, cellular deprivation and refeeding are distinguished.","comparator":null,"unit":null,"notes":"","entity":{"slug":"fasting","display_name":"Fasting / abstention from energy intake","entity_type_key":"cellular_process"}},{"dimension":"plain_language","value_text":"A fasting-associated ketone uses a receptor also used by nicotinic acid.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"(D)-beta-Hydroxybutyrate inhibits adipocyte lipolysis via the nicotinic acid receptor PUMA-G. · 2005 · https://pubmed.ncbi.nlm.nih.gov/15929991/ · DOI 10.1074/jbc.C500213200","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"ce0acd57-719c-5cbc-8ec7-61db8cbf7c44","evidence_kind":"source_excerpt","locator":"Lines 352-358","start_line":352,"end_line":358,"excerpt":"## fast-bhb-hcar2\nA fasting-associated ketone uses a receptor also used by nicotinic acid.\nD-beta-hydroxybutyrate activated human HM74a/HCAR2 and its mouse orthologue.\nModel: Human and mouse receptor pharmacology.\nLimitations: Shared receptor does not imply identical exposures or clinical effects.\nEvidence access: Primary abstract\n(D)-beta-Hydroxybutyrate inhibits adipocyte lipolysis via the nicotinic acid receptor PUMA-G. · 2005 · https://pubmed.ncbi.nlm.nih.gov/15929991/ · DOI 10.1074/jbc.C500213200","model_system":"Human and mouse receptor pharmacology.","directness":"reported_statement","verification_status":"source_derived_draft","notes":"Original curation paraphrase; evidence access and experimental limitations specified.","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"921d1eb5-2c88-52b9-9898-60b2b5bf6029","stable_key":"import-c9aa15a1-8ba2-5913-b2dd-372af304bf87","title":"Fasting: fuel switching, nutrient sensing, ketone signaling, nutrient dependencies and refeeding (2026-09-18)","document_type":"imported_text","citation_label":"AI-assisted research curation; primary-abstract references and experimental limitations individually identified. Not publisher full text.","file_path":"","sha256":"991b7fd94be84c0f1e622e0672eda03d600b388dfd7825e219aa1678d1c7983a","revision_id":"ce85d3f4-4eaf-5aee-bddb-0f0ce7fe2211","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}