{"id":"614d7e10-389b-5844-88a5-af8b5e8b9c52","stable_key":"a9dd23c6-978a-5755-8bd8-f29bd1fe0cda:nia-clin-nmn-muscle-nad","predicate":"does_not_increase_measured","statement":"Muscle NAD+ content did not rise after NMN even though PBMC NAD+ and muscle methylated niacin metabolites increased; authors interpreted the latter as consistent with increased turnover.","claim_class":"observational","status":"source_derived_draft","evidence_grade":"ungraded","direction":"neutral","is_public":true,"mechanism_event_id":"31733f98-e97d-5a65-af6c-2800a98558a4","mechanism_event_label":"More NAD-related activity did not necessarily mean a larger standing NAD pool in muscle.","subject":{"id":"d1c59139-db61-5fa0-a25d-40c3e625152e","slug":"nmn","display_name":"NMN","entity_type_key":"small_molecule"},"object":{"id":"826d060f-7c48-5f10-af28-a016c03a52b0","slug":"skeletal-muscle-nad-plus-content","display_name":"Skeletal muscle NAD+ content","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"31733f98-e97d-5a65-af6c-2800a98558a4","stable_key":"a9dd23c6-978a-5755-8bd8-f29bd1fe0cda:nia-clin-nmn-muscle-nad-event","event_type":"observed_intervention","label":"More NAD-related activity did not necessarily mean a larger standing NAD pool in muscle.","description":"Muscle NAD+ content did not rise after NMN even though PBMC NAD+ and muscle methylated niacin metabolites increased; authors interpreted the latter as consistent with increased turnover.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"283ed24b-06a1-50aa-9281-df3bac6ce37e","slug":"nad-plus","display_name":"NAD+","entity_type_key":"small_molecule"},"role":"coenzyme","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"5d85872f-c88c-5e8b-a2c6-99a1eb636431","slug":"pbmc-nad-plus-content","display_name":"PBMC NAD+ content","entity_type_key":"cellular_process"},"role":"separate_compartment_marker","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"b02a63e0-a972-53c5-8a3a-eea6b7578cd5","slug":"n1-methylnicotinamide","display_name":"N1-Methylnicotinamide","entity_type_key":"small_molecule"},"role":"muscle_metabolite","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":"subject","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"826d060f-7c48-5f10-af28-a016c03a52b0","slug":"skeletal-muscle-nad-plus-content","display_name":"Skeletal muscle NAD+ content","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""}]},"contexts":[{"dimension":"cross_nutrient","value_text":"Nicotinamide adenine dinucleotide, oxidized (coenzyme); PBMC NAD+ content (separate_compartment_marker); N1-methylnicotinamide (muscle_metabolite)","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/niacin-clinical-sources/yoshino2021.txt\", \"locator\": \"Primary full report; exact character range, zero-based and end-exclusive\", \"file_sha256\": \"e4999dc5b9d3392d8180280727c424044b35249bb24c999c3bc863cd23e6c856\", \"start_char\": 4842, \"end_char\": 6119, \"text_sha256\": \"bb73c5ac9d2ac503143ede8627aaa6be34763fdd501bf48a32528a332b89016c\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Randomized double-blind trial; 25 overweight or obese postmenopausal women with prediabetes completed","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"NMN 250 mg/day for 10 weeks; 13 NMN and 12 placebo participants","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Small selected female cohort. Tissue NAD concentration, NAD turnover and clinical outcomes differ. No lifespan or diabetes-prevention endpoint. Positive muscle findings do not establish whole-body or cross-population benefit.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Niacin research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"niacin","display_name":"Niacin (vitamin B3)","entity_type_key":"nutrient_element"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"More NAD-related activity did not necessarily mean a larger standing NAD pool in muscle.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[nia-clin-yoshino2021] Nicotinamide mononucleotide increases muscle insulin sensitivity in prediabetic women. 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Tissue NAD concentration, NAD turnover and clinical outcomes differ. No lifespan or diabetes-prevention endpoint. Positive muscle findings do not establish whole-body or cross-population benefit.\nexposure: NMN 250 mg/day for 10 weeks; 13 NMN and 12 placebo participants\ncross_nutrient: Nicotinamide adenine dinucleotide, oxidized (coenzyme); PBMC NAD+ content (separate_compartment_marker); N1-methylnicotinamide (muscle_metabolite)\nevidence_span: {\"source_cache\": \"artifacts/niacin-clinical-sources/yoshino2021.txt\", \"locator\": \"Primary full report; exact character range, zero-based and end-exclusive\", \"file_sha256\": \"e4999dc5b9d3392d8180280727c424044b35249bb24c999c3bc863cd23e6c856\", \"start_char\": 4842, \"end_char\": 6119, \"text_sha256\": \"bb73c5ac9d2ac503143ede8627aaa6be34763fdd501bf48a32528a332b89016c\"}\n[nia-clin-yoshino2021] Nicotinamide mononucleotide increases muscle insulin sensitivity in prediabetic women. 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