{"id":"34c6975f-350f-529e-bc2e-d0e57feee76b","stable_key":"46d15d9e-d3b5-544d-ba01-b785aa3e4f42:b1-colon-intact-thdp-uptake","predicate":"undergoes","statement":"NCM460 colonocytes took up radiolabeled ThDP without prior substrate dephosphorylation; native human apical vesicles also showed carrier-mediated uptake.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"70937b96-df7c-5f90-8f51-191055215d23","mechanism_event_label":"Colon cells can absorb the phosphorylated B1 form directly.","subject":{"id":"187db168-8028-5ce6-9f8b-4bc61ebad1a0","slug":"thiamine-diphosphate","display_name":"Thiamine diphosphate","entity_type_key":"small_molecule"},"object":{"id":"d18cb660-a99f-509a-ae45-22cce11d2495","slug":"colonic-thdp-uptake","display_name":"Colonic thiamine diphosphate uptake","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"70937b96-df7c-5f90-8f51-191055215d23","stable_key":"46d15d9e-d3b5-544d-ba01-b785aa3e4f42:b1-colon-intact-thdp-uptake-event","event_type":"biochemical_relationship","label":"Colon cells can absorb the phosphorylated B1 form directly.","description":"NCM460 colonocytes took up radiolabeled ThDP without prior substrate dephosphorylation; native human apical vesicles also showed carrier-mediated uptake.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"36b7c3eb-068b-500f-af1c-078829df1ecc","slug":"thiamine","display_name":"Thiamine (vitamin B1)","entity_type_key":"small_molecule"},"role":"chemically distinct free form","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"2d52919c-025a-5772-92b0-6229c0b74ba3","slug":"thiamine-monophosphate","display_name":"Thiamine monophosphate","entity_type_key":"small_molecule"},"role":"distinct phosphate form","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"187db168-8028-5ce6-9f8b-4bc61ebad1a0","slug":"thiamine-diphosphate","display_name":"Thiamine diphosphate","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"d18cb660-a99f-509a-ae45-22cce11d2495","slug":"colonic-thdp-uptake","display_name":"Colonic thiamine diphosphate uptake","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"evidence-scope","value_text":"Colonocytes; colonic apical membranes","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_locator","value_text":"Abstract","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_spans","value_text":"[{\"source_document\": \"artifacts/thiamine_transport_sources/nabokina-2012-colonic-tpp-source-record.json\", \"source_field\": \"resultList.result[0].abstractText\", \"start_char\": 0, \"end_char\": 1813}]","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"NCM460 cells and human donor colonic apical vesicles; custom tritiated ThDP.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Does not quantify systemic contribution from gut microbial B1.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Thiamine research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"thiamine","display_name":"Thiamine (vitamin B1)","entity_type_key":"small_molecule"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Colon cells can absorb the phosphorylated B1 form directly.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[nabokina-2012-colonic-tpp] A high-affinity and specific carrier-mediated mechanism for uptake of thiamine pyrophosphate by human colonic epithelial cells (2012). https://pmc.ncbi.nlm.nih.gov/articles/PMC3423106/ DOI: 10.1152/ajpgi.00151.2012","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Colonocytes; colonic apical membranes","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"transport_direction","value_text":"Luminal/apical compartment into colonocytes.","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"fbf1e8e5-516e-5b8b-97c7-9051fe1066ca","evidence_kind":"source_excerpt","locator":"Lines 502-515","start_line":502,"end_line":515,"excerpt":"### b1-colon-intact-thdp-uptake\nNCM460 colonocytes took up radiolabeled ThDP without prior substrate dephosphorylation; native human apical vesicles also showed carrier-mediated uptake.\nCondition category: normal\nnutrient_topic: Thiamine research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Colon cells can absorb the phosphorylated B1 form directly.\norganism: Homo sapiens\ntissue_or_cell_type: Colonocytes; colonic apical membranes\nexperimental_model: NCM460 cells and human donor colonic apical vesicles; custom tritiated ThDP.\nlimitations: Does not quantify systemic contribution from gut microbial B1.\ntransport_direction: Luminal/apical compartment into colonocytes.\nevidence_spans: [{\"source_document\": \"artifacts/thiamine_transport_sources/nabokina-2012-colonic-tpp-source-record.json\", \"source_field\": \"resultList.result[0].abstractText\", \"start_char\": 0, \"end_char\": 1813}]\nevidence_locator: Abstract\nevidence-scope: Colonocytes; colonic apical membranes\n[nabokina-2012-colonic-tpp] A high-affinity and specific carrier-mediated mechanism for uptake of thiamine pyrophosphate by human colonic epithelial cells (2012). https://pmc.ncbi.nlm.nih.gov/articles/PMC3423106/ DOI: 10.1152/ajpgi.00151.2012","model_system":"NCM460 cells and human donor colonic apical vesicles; custom tritiated ThDP.","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [nabokina-2012-colonic-tpp] A high-affinity and specific carrier-mediated mechanism for uptake of thiamine pyrophosphate by human colonic epithelial cells (2012). https://pmc.ncbi.nlm.nih.gov/articles/PMC3423106/ DOI: 10.1152/ajpgi.00151.2012","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"158d2c03-ac8c-589f-8270-c468165ae346","stable_key":"import-46d15d9e-d3b5-544d-ba01-b785aa3e4f42","title":"Thiamine: 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":"f376512fb3310141315548015b387833e3af45146e73fb73cd02cee20e4ddb9c","revision_id":"53bc5eda-dec8-58cc-a56f-a9eb4ab036ef","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}