{"id":"92c85d43-3944-5302-b786-9543187e6fae","stable_key":"1deb434a-3547-51a0-a038-87b1ce79ec38:vdm-calcitriol-induces-cldn12","predicate":"increases_expression","statement":"Calcitriol increased Claudin-12 expression in human Caco-2 intestinal epithelial cells.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"0976244c-3aa4-55ca-84f3-78d6f855c1bd","mechanism_event_label":"Active vitamin D can increase a tight-junction protein involved in calcium movement between intestinal cells.","subject":{"id":"f5156c24-108f-5746-b114-ed764e79a3f4","slug":"calcitriol","display_name":"Calcitriol","entity_type_key":"small_molecule"},"object":{"id":"e6ebb895-0787-5d8b-8aca-1b5e2f827366","slug":"cldn12","display_name":"Claudin-12","entity_type_key":"protein"},"evidence_count":1,"mechanism_event":{"id":"0976244c-3aa4-55ca-84f3-78d6f855c1bd","stable_key":"1deb434a-3547-51a0-a038-87b1ce79ec38:vdm-calcitriol-induces-cldn12-event","event_type":"biochemical_relationship","label":"Active vitamin D can increase a tight-junction protein involved in calcium movement between intestinal cells.","description":"Calcitriol increased Claudin-12 expression in human Caco-2 intestinal epithelial cells.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"f5156c24-108f-5746-b114-ed764e79a3f4","slug":"calcitriol","display_name":"Calcitriol","entity_type_key":"small_molecule"},"role":"hormonal-regulator","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"d725020b-bacc-5e90-b370-cda246025c91","slug":"vdr","display_name":"Vitamin D receptor / VDR","entity_type_key":"protein"},"role":"receptor","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"e6ebb895-0787-5d8b-8aca-1b5e2f827366","slug":"cldn12","display_name":"Claudin-12","entity_type_key":"protein"},"role":"regulated-junction-protein","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"e359bc15-e675-5d83-b0fe-1d70814e130b","slug":"calcium-ion","display_name":"Calcium ion","entity_type_key":"ion"},"role":"transported-ion-context","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":"Primary abstract and Results/Discussion on calcitriol-induced claudin expression; cached web-primary-excerpts.json","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":"Human Caco-2 cells; RT-PCR, immunoblotting and junctional localization","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Calcitriol-treated versus vehicle Caco-2 cultures; exact hormone dose/time not recovered in the primary passages used.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Cell-line expression response; the separately reused permeability experiments support function, but neither establishes a universal fraction of human dietary calcium absorption.","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":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Active vitamin D can increase a tight-junction protein involved in calcium movement between intestinal cells.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[vdm-fujita2008] Tight junction proteins claudin-2 and -12 are critical for vitamin D-dependent Ca2+ absorption between enterocytes. (2008). https://pubmed.ncbi.nlm.nih.gov/18287530/ DOI: 10.1091/mbc.e07-09-0973","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Intestinal epithelial cell model","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"b455c250-ac82-5822-b487-1f434dd7ae22","evidence_kind":"source_excerpt","locator":"Lines 633-647","start_line":633,"end_line":647,"excerpt":"### vdm-calcitriol-induces-cldn12\nCalcitriol increased Claudin-12 expression in human Caco-2 intestinal epithelial cells.\nCondition category: normal\nnutrient_topic: Vitamin D2 and D3 research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Active vitamin D can increase a tight-junction protein involved in calcium movement between intestinal cells.\norganism: Homo sapiens\ntissue_or_cell_type: Intestinal epithelial cell model\nexperimental_model: Human Caco-2 cells; RT-PCR, immunoblotting and junctional localization\nlimitations: Cell-line expression response; the separately reused permeability experiments support function, but neither establishes a universal fraction of human dietary calcium absorption.\nexposure: Calcitriol-treated versus vehicle Caco-2 cultures; exact hormone dose/time not recovered in the primary passages used.\ncross_nutrient: Vitamin D–calcium–phosphate regulation.\nevidence_locator: Primary abstract and Results/Discussion on calcitriol-induced claudin expression; cached web-primary-excerpts.json\nnutrient: Vitamin D2 and D3\nevidence_scope: D3 active metabolite or VDR machinery experiment; not a direct D2-versus-D3 comparison.\n[vdm-fujita2008] Tight junction proteins claudin-2 and -12 are critical for vitamin D-dependent Ca2+ absorption between enterocytes. (2008). https://pubmed.ncbi.nlm.nih.gov/18287530/ DOI: 10.1091/mbc.e07-09-0973","model_system":"Human Caco-2 cells; RT-PCR, immunoblotting and junctional localization","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [vdm-fujita2008] Tight junction proteins claudin-2 and -12 are critical for vitamin D-dependent Ca2+ absorption between enterocytes. (2008). https://pubmed.ncbi.nlm.nih.gov/18287530/ DOI: 10.1091/mbc.e07-09-0973","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}