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It is explicitly a hypothesis about mitochondrial activity, not a cellular measurement.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Metformin research collection; topical membership is not evidence of a direct clinical effect, and pharmacological exposure is not dietary intake.","comparator":null,"unit":null,"notes":"","entity":{"slug":"metformin","display_name":"Metformin","entity_type_key":"drug"}},{"dimension":"organism","value_text":"Chemical and computational","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"The drug grabs copper tightly enough that it could pull it off proteins and oxidise it.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[metformin-p24433134] Biomolecular mode of action of metformin in relation to its copper binding properties. (2014). https://pubmed.ncbi.nlm.nih.gov/24433134/ DOI: 10.1021/bi401444n","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Molecular interaction","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"b983e62a-d32f-5335-868d-a1cdac86b5eb","evidence_kind":"source_excerpt","locator":"Lines 1373-1384","start_line":1373,"end_line":1384,"excerpt":"### metformin-copper-binding-chemistry\nMetformin can occur as an anion in aqueous medium at moderate pH and forms much stronger complexes with Cu(II) ions than the comparator propanediimidamide, suggesting that biguanides may induce oxidation of Cu(I) ions extracted from proteins.\nCondition category: normal\nnutrient_topic: Metformin research collection; topical membership is not evidence of a direct clinical effect, and pharmacological exposure is not dietary intake.\nplain_language: The drug grabs copper tightly enough that it could pull it off proteins and oxidise it.\norganism: Chemical and computational\ntissue_or_cell_type: Molecular interaction\nexperimental_model: Computational and binding comparison of metformin and propanediimidamide with copper\nlimitations: A chemistry study proposing a pro-oxidant role. It is explicitly a hypothesis about mitochondrial activity, not a cellular measurement.\nexposure: Copper(I) and copper(II) binding energies, pKa and hydrophilicity\nevidence_span: {\"source_cache\": \"artifacts/metformin-research/24433134.abstract.txt\", \"locator\": \"Indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"a6dda36e30a49ba48e8200b6de36f39a8ab80a1bcbda819c03d3442bb8705963\", \"start_char\": 0, \"end_char\": 1430, \"text_sha256\": \"a6dda36e30a49ba48e8200b6de36f39a8ab80a1bcbda819c03d3442bb8705963\"}\n[metformin-p24433134] Biomolecular mode of action of metformin in relation to its copper binding properties. (2014). https://pubmed.ncbi.nlm.nih.gov/24433134/ DOI: 10.1021/bi401444n","model_system":"Computational and binding comparison of metformin and propanediimidamide with copper","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. 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