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(2005). https://pubmed.ncbi.nlm.nih.gov/15976027/ DOI: 10.1073/pnas.0502249102","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Cultured hypertrophic chondrocytes","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"ecbb1117-ed84-5ac1-a4ea-664b0524c5b6","evidence_kind":"source_excerpt","locator":"Lines 793-807","start_line":793,"end_line":807,"excerpt":"### vdm-phosphate-activates-chondrocyte-caspase9\nPhosphate exposure activated the caspase-9-dependent mitochondrial apoptotic pathway in cultured primary mouse hypertrophic chondrocytes.\nCondition category: normal\nnutrient_topic: Vitamin D2 and D3 research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Phosphate served as a signal for a cartilage-cell maturation pathway in this culture system.\norganism: Mus musculus\ntissue_or_cell_type: Cultured hypertrophic chondrocytes\nexperimental_model: Primary mouse chondrocytes; caspase-9 pathway and apoptosis assays\nlimitations: Cell differentiation and exposure conditions matter; no nutrient dose recommendation, universal phosphate sensor or human serum threshold is established.\nexposure: Inorganic phosphate exposure in differentiated primary cultures; exact dose/time not recovered in the primary passages used.\ncross_nutrient: Vitamin D–calcium–phosphate regulation.\nevidence_locator: Primary abstract and opening experimental-results summary; web-assay-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-sabbagh2005] Hypophosphatemia leads to rickets by impairing caspase-mediated apoptosis of hypertrophic chondrocytes. 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