Component

Plasma retinol concentration

Measured blood-compartment retinol; not a universal intracellular availability threshold.

4 recorded relationships. Experimental role, claim status and evidence remain attached to each record.

Read recorded mechanisms Open recursive mind map

How nutrients influence it

Every nutrient with a recorded effect on this component, credited to the nutrient that acted rather than the chapter that recorded it. Open a nutrient to see the findings and the conditions they were measured under.

How nutrients reach it in more than one step

Chains of two or more recorded steps that end here, grouped by the nutrient they start from. Each step is a separate finding, so a chain is a route a mechanism could take, not proof that it does.

Tracing routes…

What it does

Every recorded relationship this component is part of, grouped by its role. Plain wording comes first; the technical statement follows.

Recorded relationships

What acts on it

  1. Iron increased plasma retinol, RBP and transthyretin; the combined iron/zinc arm increased retinol without significant carrier-protein increases.

    Iron → Plasma retinol concentration source_derived_draftungraded
    Experimental context and source evidence
    cross_nutrient
    Iron/zinc -> retinoid transport markers.
    experimental_model
    Same factorial trial.
    limitations
    Measured biomarkers do not prove the molecular mechanism.
    nutrient_topic
    Vitamin A research collection; topical membership is not evidence of a direct dietary effect. · Vitamin A
    organism
    Homo sapiens
    plain_language
    The two minerals did not produce identical carrier-protein responses.
    primary_references
    [va-munoz2000] Iron and zinc supplementation improves indicators of vitamin A status of Mexican preschoolers (2000). https://pubmed.ncbi.nlm.nih.gov/10702174/ DOI: 10.1093/ajcn/71.3.789
    tissue_or_cell_type
    Plasma

    Vitamin A: forms, mechanisms, deficiency and excess (2026-09-17) · lines 1495–1505

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Same factorial trial. · source_derived_draft · unverified_draft

    ### va-iron-improves-retinol-marker Iron increased plasma retinol, RBP and transthyretin; the combined iron/zinc arm increased retinol without significant carrier-protein increases. Condition category: normal nutrient_topic: Vitamin A research collection; topical membership is not evidence of a direct dietary effect. plain_language: The two minerals did not produce identical carrier-protein responses. organism: Homo sapiens tissue_or_cell_type: Plasma experimental_model: Same factorial trial. limitations: Measured biomarkers do not prove the molecular mechanism. cross_nutrient: Iron/zinc -> retinoid transport markers. [va-munoz2000] Iron and zinc supplementation improves indicators of vitamin A status of Mexican preschoolers (2000). https://pubmed.ncbi.nlm.nih.gov/10702174/ DOI: 10.1093/ajcn/71.3.789
    Complete structured claim and evidence

  2. LPS lowered circulating retinol without a detected decrease in liver or kidney retinol in vitamin A-sufficient rats.

    Lipopolysaccharide → Plasma retinol concentration source_derived_draftungraded
    Experimental context and source evidence
    availability_state
    biomarker_context Imported condition classification; unverified.
    experimental_model
    LPS versus saline with food withdrawal.
    limitations
    Acute rat model; not every inflammatory illness follows the same kinetics.
    nutrient_topic
    Vitamin A research collection; topical membership is not evidence of a direct dietary effect. · Vitamin A
    organism
    Rattus norvegicus
    plain_language
    A low blood value did not mean the measured tissue stores had been emptied.
    primary_references
    [va-rosales1996] Effects of acute inflammation on plasma retinol, retinol-binding protein, and its mRNA in the liver and kidneys of vitamin A-sufficient rats (1996). https://pubmed.ncbi.nlm.nih.gov/8725149/ DOI: 10.1016/s0022-2275(20)42007-3
    tissue_or_cell_type
    Plasma, liver and kidney
    trigger_kind
    biomarker_context Imported condition classification; unverified.

    Vitamin A: forms, mechanisms, deficiency and excess (2026-09-17) · lines 1674–1683

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · LPS versus saline with food withdrawal. · source_derived_draft · unverified_draft

    ### va-lps-lowers-retinol-with-stores LPS lowered circulating retinol without a detected decrease in liver or kidney retinol in vitamin A-sufficient rats. Condition category: biomarker_context nutrient_topic: Vitamin A research collection; topical membership is not evidence of a direct dietary effect. plain_language: A low blood value did not mean the measured tissue stores had been emptied. organism: Rattus norvegicus tissue_or_cell_type: Plasma, liver and kidney experimental_model: LPS versus saline with food withdrawal. limitations: Acute rat model; not every inflammatory illness follows the same kinetics. [va-rosales1996] Effects of acute inflammation on plasma retinol, retinol-binding protein, and its mRNA in the liver and kidneys of vitamin A-sufficient rats (1996). https://pubmed.ncbi.nlm.nih.gov/8725149/ DOI: 10.1016/s0022-2275(20)42007-3
    Complete structured claim and evidence

  3. Ttr-null mice had plasma retinol averaging about 6% of wild type.

    Transthyretin / TTR → Plasma retinol concentration source_derived_draftungraded
    Experimental context and source evidence
    availability_state
    machinery_impairment Imported condition classification; unverified.
    evidence_location
    Abstract
    experimental_model
    Ttr-knockout mice; circulating and tissue retinoid assays.
    exposure
    Ttr knockout; pooled plasma comparison.
    limitations
    Not evidence that every tissue was depleted; the mechanism of the plasma fall was incompletely resolved.
    nutrient_topic
    Vitamin A research collection; topical membership is not evidence of a direct dietary effect. · Vitamin A
    organism
    Mus musculus
    outcome
    Ttr-null mice had plasma retinol averaging about 6% of wild type.
    plain_language
    Loss of the RBP-associated carrier strongly lowers the blood measurement.
    primary_references
    [va-wei-1995] Studies on the metabolism of retinol and retinol-binding protein in transthyretin-deficient mice produced by homologous recombination (1995). https://pubmed.ncbi.nlm.nih.gov/7822324/ DOI: 10.1074/jbc.270.2.866
    tissue_or_cell_type
    Plasma
    trigger_kind
    machinery_impairment Imported condition classification; unverified.

    Vitamin A: forms, mechanisms, deficiency and excess (2026-09-17) · lines 402–414

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Ttr-knockout mice; circulating and tissue retinoid assays. · source_derived_draft · unverified_draft

    ### va-ttr-plasma-retinol Ttr-null mice had plasma retinol averaging about 6% of wild type. Condition category: machinery_impairment nutrient_topic: Vitamin A research collection; topical membership is not evidence of a direct dietary effect. plain_language: Loss of the RBP-associated carrier strongly lowers the blood measurement. organism: Mus musculus tissue_or_cell_type: Plasma experimental_model: Ttr-knockout mice; circulating and tissue retinoid assays. limitations: Not evidence that every tissue was depleted; the mechanism of the plasma fall was incompletely resolved. exposure: Ttr knockout; pooled plasma comparison. outcome: Ttr-null mice had plasma retinol averaging about 6% of wild type. evidence_location: Abstract [va-wei-1995] Studies on the metabolism of retinol and retinol-binding protein in transthyretin-deficient mice produced by homologous recombination (1995). https://pubmed.ncbi.nlm.nih.gov/7822324/ DOI: 10.1074/jbc.270.2.866
    Complete structured claim and evidence

  4. Zinc increased plasma retinol and transthyretin versus placebo; the RBP increase was not significant.

    Zinc → Plasma retinol concentration source_derived_draftungraded
    Experimental context and source evidence
    cross_nutrient
    Zinc -> vitamin A biomarkers.
    experimental_model
    Six-month preschool trial.
    limitations
    No direct proof of restored liver release or increased RBP synthesis.
    nutrient_topic
    Vitamin A research collection; topical membership is not evidence of a direct dietary effect. · Vitamin A
    organism
    Homo sapiens
    plain_language
    Zinc status can influence vitamin A transport-related blood measurements.
    primary_references
    [va-munoz2000] Iron and zinc supplementation improves indicators of vitamin A status of Mexican preschoolers (2000). https://pubmed.ncbi.nlm.nih.gov/10702174/ DOI: 10.1093/ajcn/71.3.789
    tissue_or_cell_type
    Plasma

    Vitamin A: forms, mechanisms, deficiency and excess (2026-09-17) · lines 1483–1493

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Six-month preschool trial. · source_derived_draft · unverified_draft

    ### va-zinc-improves-retinol-marker Zinc increased plasma retinol and transthyretin versus placebo; the RBP increase was not significant. Condition category: normal nutrient_topic: Vitamin A research collection; topical membership is not evidence of a direct dietary effect. plain_language: Zinc status can influence vitamin A transport-related blood measurements. organism: Homo sapiens tissue_or_cell_type: Plasma experimental_model: Six-month preschool trial. limitations: No direct proof of restored liver release or increased RBP synthesis. cross_nutrient: Zinc -> vitamin A biomarkers. [va-munoz2000] Iron and zinc supplementation improves indicators of vitamin A status of Mexican preschoolers (2000). https://pubmed.ncbi.nlm.nih.gov/10702174/ DOI: 10.1093/ajcn/71.3.789
    Complete structured claim and evidence

In the sources

Preserved passages that mention this component, quoted exactly. Open one to read it in context.

    This is a research prototype built from draft material. It is not medical advice, and its statements still await verification against the original studies.

    Evidence, AI assistance and curation standards