{"id":"d40ed764-5f4f-5446-af39-5ab251d245c7","stable_key":"8c946991-97f0-55ee-8df0-00e67621962f:nad-plus-oral-versus-iv-precursors","predicate":"undergoes_route_dependent_metabolism","statement":"In mouse tracer experiments, oral NR and NMN were largely metabolized to nicotinamide, whereas intravenous administration delivered intact precursors to multiple tissues.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"00dd3e82-bc21-5c4b-8910-f1efe199d747","mechanism_event_label":"Route of administration changes which molecules tissues encounter.","subject":{"id":"7bb72d0e-e20d-51bc-b88b-7ff29dc2ad4a","slug":"nicotinamide-riboside","display_name":"Nicotinamide riboside","entity_type_key":"small_molecule"},"object":{"id":"08c27a3f-552e-5c92-8688-321a9b64a0d6","slug":"nicotinamide","display_name":"Nicotinamide","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"00dd3e82-bc21-5c4b-8910-f1efe199d747","stable_key":"8c946991-97f0-55ee-8df0-00e67621962f:nad-plus-oral-versus-iv-precursors-event","event_type":"observed_relationship","label":"Route of administration changes which molecules tissues encounter.","description":"In mouse tracer experiments, oral NR and NMN were largely metabolized to nicotinamide, whereas intravenous administration delivered intact precursors to multiple tissues.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"7bb72d0e-e20d-51bc-b88b-7ff29dc2ad4a","slug":"nicotinamide-riboside","display_name":"Nicotinamide riboside","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"08c27a3f-552e-5c92-8688-321a9b64a0d6","slug":"nicotinamide","display_name":"Nicotinamide","entity_type_key":"small_molecule"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"283ed24b-06a1-50aa-9281-df3bac6ce37e","slug":"nad-plus","display_name":"NAD+","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"d1c59139-db61-5fa0-a25d-40c3e625152e","slug":"nmn","display_name":"NMN","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"evidence_access","value_text":"Primary full text","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Mouse oral versus intravenous isotope-labeled precursor administration.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"This study tests NR/NMN, not intact NAD infusion; it does not establish an optimal human route.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"NAD+ collection; molecular form, preparation, species, exposure and manipulation remain explicit.","comparator":null,"unit":null,"notes":"","entity":{"slug":"nad-plus","display_name":"NAD+","entity_type_key":"small_molecule"}},{"dimension":"plain_language","value_text":"Route of administration changes which molecules tissues encounter.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"Quantitative Analysis of NAD Synthesis-Breakdown Fluxes. · 2018 · https://pubmed.ncbi.nlm.nih.gov/29685734/ · DOI 10.1016/j.cmet.2018.03.018","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"398ae0fd-cded-5218-8c46-c24069d2ac02","evidence_kind":"source_excerpt","locator":"Lines 196-202","start_line":196,"end_line":202,"excerpt":"## nad-plus-oral-versus-iv-precursors\nRoute of administration changes which molecules tissues encounter.\nIn mouse tracer experiments, oral NR and NMN were largely metabolized to nicotinamide, whereas intravenous administration delivered intact precursors to multiple tissues.\nModel: Mouse oral versus intravenous isotope-labeled precursor administration.\nLimitations: This study tests NR/NMN, not intact NAD infusion; it does not establish an optimal human route.\nEvidence access: Primary full text\nQuantitative Analysis of NAD Synthesis-Breakdown Fluxes. · 2018 · https://pubmed.ncbi.nlm.nih.gov/29685734/ · DOI 10.1016/j.cmet.2018.03.018","model_system":"Mouse oral versus intravenous isotope-labeled precursor administration.","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":"f59aa302-d463-5462-876f-e21e64861eac","stable_key":"import-8c946991-97f0-55ee-8df0-00e67621962f","title":"NAD+: compartmental supply, consumption and cross-nutrient mechanisms (2026-09-19)","document_type":"imported_text","citation_label":"AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text.","file_path":"","sha256":"9f5324d0d652c80ad630b3100e28ce34cd2ce260ea2e1324332a4262ce72ae09","revision_id":"0e07909c-e8bc-5950-bafc-61371d9d6412","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}