{"id":"bbb8d20b-d81e-5a6a-909d-f201e7565f3d","stable_key":"1deb434a-3547-51a0-a038-87b1ce79ec38:vdm-fgf23-reduces-renal-napi2a","predicate":"reduces_expression","statement":"Recombinant FGF23 reduced renal NaPi-IIa mRNA and protein abundance in the acute rodent injection study.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"negative","is_public":true,"mechanism_event_id":"85f59e85-3c99-5526-b10b-e8a183013dc9","mechanism_event_label":"FGF23 reduced a kidney transporter that normally helps retain phosphate.","subject":{"id":"6edbc5a6-fcb5-516d-9c86-66950a8984b3","slug":"fgf23","display_name":"Fibroblast growth factor 23 / FGF23","entity_type_key":"protein"},"object":{"id":"b3fe4fe6-7a14-5c14-a5f8-a522fc67cdcd","slug":"slc34a1","display_name":"Sodium-phosphate cotransporter NaPi-IIa / SLC34A1","entity_type_key":"protein"},"evidence_count":1,"mechanism_event":{"id":"85f59e85-3c99-5526-b10b-e8a183013dc9","stable_key":"1deb434a-3547-51a0-a038-87b1ce79ec38:vdm-fgf23-reduces-renal-napi2a-event","event_type":"biochemical_relationship","label":"FGF23 reduced a kidney transporter that normally helps retain phosphate.","description":"Recombinant FGF23 reduced renal NaPi-IIa mRNA and protein abundance in the acute rodent injection study.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"6edbc5a6-fcb5-516d-9c86-66950a8984b3","slug":"fgf23","display_name":"Fibroblast growth factor 23 / FGF23","entity_type_key":"protein"},"role":"hormonal-regulator","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"b3fe4fe6-7a14-5c14-a5f8-a522fc67cdcd","slug":"slc34a1","display_name":"Sodium-phosphate cotransporter NaPi-IIa / SLC34A1","entity_type_key":"protein"},"role":"regulated-transporter","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"b28dfc54-a5ef-5f9e-ac1f-890b68e58dc3","slug":"inorganic-phosphate","display_name":"Inorganic phosphate","entity_type_key":"chemical_species"},"role":"transport-substrate","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"38de8704-84db-5770-ac1d-242cd787e798","slug":"sodium-ion","display_name":"Sodium ion","entity_type_key":"ion"},"role":"cotransported-ion","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"cross_nutrient","value_text":"Vitamin D–calcium–phosphate regulation.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_locator","value_text":"Abstract: reported experimental results","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_scope","value_text":"D3 active metabolite or VDR machinery experiment; not a direct D2-versus-D3 comparison.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Single recombinant FGF23 injection in rodents; renal transcript/protein and serum phosphate measurements","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Single recombinant FGF23 injection; serum phosphate reduction was first observed at 9 hours; dose not recovered in the primary abstract.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Transporter abundance is not itself a flux measurement. Lack of a PTH rise and parathyroidectomized-rat responses support a PTH-independent action in this experiment.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient","value_text":"Vitamin D2 and D3","comparator":null,"unit":null,"notes":"","entity":{"slug":"vitamin-d","display_name":"Vitamin D2 and D3","entity_type_key":"chemical_species"}},{"dimension":"nutrient_topic","value_text":"Vitamin D2 and D3 research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"vitamin-d","display_name":"Vitamin D2 and D3","entity_type_key":"chemical_species"}},{"dimension":"organism","value_text":"Mus musculus; Rattus norvegicus","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"FGF23 reduced a kidney transporter that normally helps retain phosphate.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[vdm-shimada2004] FGF-23 is a potent regulator of vitamin D metabolism and phosphate homeostasis. (2004). https://pubmed.ncbi.nlm.nih.gov/15040831/ DOI: 10.1359/jbmr.0301264","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Kidney","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"c90d1149-a23e-508f-89ae-332763f6f260","evidence_kind":"source_excerpt","locator":"Lines 745-759","start_line":745,"end_line":759,"excerpt":"### vdm-fgf23-reduces-renal-napi2a\nRecombinant FGF23 reduced renal NaPi-IIa mRNA and protein abundance in the acute rodent injection study.\nCondition category: normal\nnutrient_topic: Vitamin D2 and D3 research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: FGF23 reduced a kidney transporter that normally helps retain phosphate.\norganism: Mus musculus; Rattus norvegicus\ntissue_or_cell_type: Kidney\nexperimental_model: Single recombinant FGF23 injection in rodents; renal transcript/protein and serum phosphate measurements\nlimitations: Transporter abundance is not itself a flux measurement. Lack of a PTH rise and parathyroidectomized-rat responses support a PTH-independent action in this experiment.\nexposure: Single recombinant FGF23 injection; serum phosphate reduction was first observed at 9 hours; dose not recovered in the primary abstract.\ncross_nutrient: Vitamin D–calcium–phosphate regulation.\nevidence_locator: Abstract: reported experimental results\nnutrient: Vitamin D2 and D3\nevidence_scope: D3 active metabolite or VDR machinery experiment; not a direct D2-versus-D3 comparison.\n[vdm-shimada2004] FGF-23 is a potent regulator of vitamin D metabolism and phosphate homeostasis. (2004). https://pubmed.ncbi.nlm.nih.gov/15040831/ DOI: 10.1359/jbmr.0301264","model_system":"Single recombinant FGF23 injection in rodents; renal transcript/protein and serum phosphate measurements","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [vdm-shimada2004] FGF-23 is a potent regulator of vitamin D metabolism and phosphate homeostasis. (2004). https://pubmed.ncbi.nlm.nih.gov/15040831/ DOI: 10.1359/jbmr.0301264","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"c95c763c-5b31-5b3f-a2f8-2dfe5ef0d3ca","stable_key":"import-1deb434a-3547-51a0-a038-87b1ce79ec38","title":"Vitamin D2 and D3: mechanisms, deficiency and nutrient interactions (2026-09-17)","document_type":"imported_text","citation_label":"AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text.","file_path":"","sha256":"51004bf0d78db6146b8f198b0688a3cc7d4ea9822415a9c034f4c8790fb4e38b","revision_id":"d52ff207-a311-5f24-96f4-462838792db5","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}