{"id":"2d52705f-6876-588f-8e62-c29f2cfcdf98","stable_key":"8c946991-97f0-55ee-8df0-00e67621962f:nad-plus-microbiota-oral-precursors","predicate":"contributes_to","statement":"Stable-isotope tracing and microbiota depletion showed bacterial deamidation contributed substantially to tissue NAD increases after oral nicotinamide or NR in mice.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"c7c015e1-237a-5183-9752-614a90bc8351","mechanism_event_label":"An oral precursor may reach tissues through a microbially altered route.","subject":{"id":"621e4996-f754-5485-82d6-c35cbd88c496","slug":"mouse-gut-microbiota-nad-deamidation","display_name":"Microbiota-mediated NAD precursor deamidation in mice","entity_type_key":"cellular_process"},"object":{"id":"33fb88d5-10a4-57af-97d7-3b8acfd24288","slug":"mouse-oral-precursor-nad-response","display_name":"Mouse tissue NAD response to oral precursors","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"c7c015e1-237a-5183-9752-614a90bc8351","stable_key":"8c946991-97f0-55ee-8df0-00e67621962f:nad-plus-microbiota-oral-precursors-event","event_type":"observed_relationship","label":"An oral precursor may reach tissues through a microbially altered route.","description":"Stable-isotope tracing and microbiota depletion showed bacterial deamidation contributed substantially to tissue NAD increases after oral nicotinamide or NR in mice.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"621e4996-f754-5485-82d6-c35cbd88c496","slug":"mouse-gut-microbiota-nad-deamidation","display_name":"Microbiota-mediated NAD precursor deamidation in mice","entity_type_key":"cellular_process"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"33fb88d5-10a4-57af-97d7-3b8acfd24288","slug":"mouse-oral-precursor-nad-response","display_name":"Mouse tissue NAD response to oral precursors","entity_type_key":"cellular_process"},"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":"08c27a3f-552e-5c92-8688-321a9b64a0d6","slug":"nicotinamide","display_name":"Nicotinamide","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"7bb72d0e-e20d-51bc-b88b-7ff29dc2ad4a","slug":"nicotinamide-riboside","display_name":"Nicotinamide riboside","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""},{"entity":{"id":"9751fdb6-9b30-586f-b07a-79b8e2cd62dd","slug":"nicotinic-acid","display_name":"Nicotinic acid","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":5,"notes":""}]},"contexts":[{"dimension":"evidence_access","value_text":"Primary full text","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Mouse isotope tracing and microbiota-depletion experiments.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Not a measured human conversion fraction or proof that all formulations use the same 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":"An oral precursor may reach tissues through a microbially altered route.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"Bacteria Boost Mammalian Host NAD Metabolism by Engaging the Deamidated Biosynthesis Pathway. · 2020 · https://pubmed.ncbi.nlm.nih.gov/32130883/ · DOI 10.1016/j.cmet.2020.02.001","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"e85d7cb8-c72a-53f5-9cb7-aa677e4c18ee","evidence_kind":"source_excerpt","locator":"Lines 180-186","start_line":180,"end_line":186,"excerpt":"## nad-plus-microbiota-oral-precursors\nAn oral precursor may reach tissues through a microbially altered route.\nStable-isotope tracing and microbiota depletion showed bacterial deamidation contributed substantially to tissue NAD increases after oral nicotinamide or NR in mice.\nModel: Mouse isotope tracing and microbiota-depletion experiments.\nLimitations: Not a measured human conversion fraction or proof that all formulations use the same route.\nEvidence access: Primary full text\nBacteria Boost Mammalian Host NAD Metabolism by Engaging the Deamidated Biosynthesis Pathway. · 2020 · https://pubmed.ncbi.nlm.nih.gov/32130883/ · DOI 10.1016/j.cmet.2020.02.001","model_system":"Mouse isotope tracing and microbiota-depletion experiments.","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}