Component

Human plasma phenylalanine concentration

Context-specific entity; species, compartment and exposure are stated on each claim.

6 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. PRISM studies in 261 adults with PAH deficiency found substantial phenylalanine reductions during induction, titration and maintenance pegvaliase treatment.

    Pegvaliase, PEGylated Anabaena variabilis phenylalanine ammonia lyase → Human plasma phenylalanine concentration source_derived_draftungraded
    Experimental context and source evidence
    evidence_access
    Primary abstract
    experimental_model
    Adult phase-3 clinical program with long-term titrated exposure.
    limitations
    Immune-mediated adverse events matter: 17 events in 12 participants met acute systemic hypersensitivity/anaphylaxis criteria. This is not dietary enzyme use.
    nutrient_topic
    L-Phenylalanine collection; species, compartment, exposure, co-substrates and manipulation remain explicit. · L-Phenylalanine
    plain_language
    The bypass can lower blood phenylalanine, but has its own treatment risks.
    primary_references
    Pegvaliase for the treatment of phenylketonuria: Results of a long-term phase 3 clinical trial program (PRISM). · 2018 · https://pubmed.ncbi.nlm.nih.gov/29653686/ · DOI 10.1016/j.ymgme.2018.03.006

    L-Phenylalanine: transport, protein synthesis, cofactor recycling and cross-nutrient mechanisms (2026-09-19) · lines 246–252

    AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Adult phase-3 clinical program with long-term titrated exposure. · source_derived_draft · unverified_draft

    ## l-phenylalanine-pal-clinical The bypass can lower blood phenylalanine, but has its own treatment risks. PRISM studies in 261 adults with PAH deficiency found substantial phenylalanine reductions during induction, titration and maintenance pegvaliase treatment. Model: Adult phase-3 clinical program with long-term titrated exposure. Limitations: Immune-mediated adverse events matter: 17 events in 12 participants met acute systemic hypersensitivity/anaphylaxis criteria. This is not dietary enzyme use. Evidence access: Primary abstract Pegvaliase for the treatment of phenylketonuria: Results of a long-term phase 3 clinical trial program (PRISM). · 2018 · https://pubmed.ncbi.nlm.nih.gov/29653686/ · DOI 10.1016/j.ymgme.2018.03.006
    Complete structured claim and evidence

  2. In an 89-participant six-week PKU trial, sapropterin 10 mg/kg/day lowered mean phenylalanine by 236 micromol/L versus a 3 micromol/L rise with placebo; 44% versus 9% had at least a 30% reduction.

    Sapropterin, pharmaceutical tetrahydrobiopterin → Human plasma phenylalanine concentration source_derived_draftungraded
    Experimental context and source evidence
    evidence_access
    Primary abstract
    experimental_model
    Randomized human PKU study enriched through prior responsiveness assessment.
    limitations
    Not all PAH defects respond; trial dose is historical evidence, not individualized guidance.
    nutrient_topic
    L-Phenylalanine collection; species, compartment, exposure, co-substrates and manipulation remain explicit. · L-Phenylalanine
    plain_language
    Providing the pharmaceutical cofactor helped some patients, with substantial response variation.
    primary_references
    Efficacy of sapropterin dihydrochloride (tetrahydrobiopterin, 6R-BH4) for reduction of phenylalanine concentration in patients with phenylketonuria: a phase III randomised placebo-controlled study. · 2007 · https://pubmed.ncbi.nlm.nih.gov/17693179/ · DOI 10.1016/S0140-6736(07)61234-3

    L-Phenylalanine: transport, protein synthesis, cofactor recycling and cross-nutrient mechanisms (2026-09-19) · lines 222–228

    AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Randomized human PKU study enriched through prior responsiveness assessment. · source_derived_draft · unverified_draft

    ## l-phenylalanine-sapropterin-response Providing the pharmaceutical cofactor helped some patients, with substantial response variation. In an 89-participant six-week PKU trial, sapropterin 10 mg/kg/day lowered mean phenylalanine by 236 micromol/L versus a 3 micromol/L rise with placebo; 44% versus 9% had at least a 30% reduction. Model: Randomized human PKU study enriched through prior responsiveness assessment. Limitations: Not all PAH defects respond; trial dose is historical evidence, not individualized guidance. Evidence access: Primary abstract Efficacy of sapropterin dihydrochloride (tetrahydrobiopterin, 6R-BH4) for reduction of phenylalanine concentration in patients with phenylketonuria: a phase III randomised placebo-controlled study. · 2007 · https://pubmed.ncbi.nlm.nih.gov/17693179/ · DOI 10.1016/S0140-6736(07)61234-3
    Complete structured claim and evidence

  3. In ten adults given 3 g, solution produced an earlier, higher phenylalanine peak than capsules: 191 versus 117 micromol/L at 32 versus 123 minutes.

    Aspartame → Human plasma phenylalanine concentration source_derived_draftungraded
    Experimental context and source evidence
    availability_state
    biomarker_context Imported condition classification; unverified.
    evidence_access
    Primary abstract
    experimental_model
    Balanced Latin-square comparison.
    limitations
    Acute high-dose kinetics, not brain or safety equivalence.
    nutrient_topic
    Aspartame collection; species, compartment, exposure, co-substrates and manipulation remain explicit. · Aspartame
    plain_language
    The same dose need not give the same exposure.
    primary_references
    Plasma amino acid concentrations in normal adults administered aspartame in capsules or solution: lack of bioequivalence. · 1987 · https://pubmed.ncbi.nlm.nih.gov/3574137/ · DOI 10.1016/0026-0495(87)90052-7
    trigger_kind
    biomarker_context Imported condition classification; unverified.

    Aspartame: digestion, taste, metabolite dependencies and experimental signaling (2026-09-20) · lines 82–88

    AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Balanced Latin-square comparison. · source_derived_draft · unverified_draft

    ## aspartame-formulation-phe The same dose need not give the same exposure. In ten adults given 3 g, solution produced an earlier, higher phenylalanine peak than capsules: 191 versus 117 micromol/L at 32 versus 123 minutes. Model: Balanced Latin-square comparison. Limitations: Acute high-dose kinetics, not brain or safety equivalence. Evidence access: Primary abstract Plasma amino acid concentrations in normal adults administered aspartame in capsules or solution: lack of bioequivalence. · 1987 · https://pubmed.ncbi.nlm.nih.gov/3574137/ · DOI 10.1016/0026-0495(87)90052-7
    Complete structured claim and evidence

  4. In 18 fasted adults across 100, 150 and 200 mg/kg cohorts, mean plasma phenylalanine peaks were 20.3, 35.1 and 48.7 micromol/dL.

    Aspartame → Human plasma phenylalanine concentration source_derived_draftungraded
    Experimental context and source evidence
    availability_state
    biomarker_context Imported condition classification; unverified.
    evidence_access
    Primary abstract
    experimental_model
    Six people per dose; aspartame in orange juice.
    limitations
    Healthy subjects, not PKU; no direct neurotransmitter assay.
    nutrient_topic
    Aspartame collection; species, compartment, exposure, co-substrates and manipulation remain explicit. · Aspartame
    plain_language
    Large loads produce larger amino-acid excursions.
    primary_references
    Plasma and erythrocyte concentrations of free amino acids in adult humans administered abuse doses of aspartame. · 1981 · https://pubmed.ncbi.nlm.nih.gov/7230277/ · DOI 10.1080/15287398109529980
    trigger_kind
    biomarker_context Imported condition classification; unverified.

    Aspartame: digestion, taste, metabolite dependencies and experimental signaling (2026-09-20) · lines 138–144

    AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Six people per dose; aspartame in orange juice. · source_derived_draft · unverified_draft

    ## aspartame-high-dose-phe Large loads produce larger amino-acid excursions. In 18 fasted adults across 100, 150 and 200 mg/kg cohorts, mean plasma phenylalanine peaks were 20.3, 35.1 and 48.7 micromol/dL. Model: Six people per dose; aspartame in orange juice. Limitations: Healthy subjects, not PKU; no direct neurotransmitter assay. Evidence access: Primary abstract Plasma and erythrocyte concentrations of free amino acids in adult humans administered abuse doses of aspartame. · 1981 · https://pubmed.ncbi.nlm.nih.gov/7230277/ · DOI 10.1080/15287398109529980
    Complete structured claim and evidence

  5. After 34 mg/kg, twelve female PKU heterozygotes had higher peak phenylalanine than ten noncarrier females, 15.1 versus 8.95 micromol/dL.

    Aspartame → Human plasma phenylalanine concentration source_derived_draftungraded
    Experimental context and source evidence
    availability_state
    biomarker_context Imported condition classification; unverified.
    evidence_access
    Primary abstract
    experimental_model
    Human carrier comparison, also including twelve noncarrier men.
    limitations
    Heterozygotes do not represent patients with biallelic PAH deficiency; the damaged male-baseline sentence in indexed abstract is not reconstructed.
    nutrient_topic
    Aspartame collection; species, compartment, exposure, co-substrates and manipulation remain explicit. · Aspartame
    plain_language
    Reduced metabolic reserve can change the response to a precursor source.
    primary_references
    Plasma phenylalanine levels in phenylketonuric heterozygous and normal adults administered aspartame at 34 mg/kg body weight. · 1981 · https://pubmed.ncbi.nlm.nih.gov/7268794/ · DOI 10.1016/0300-483x(81)90108-6
    trigger_kind
    biomarker_context Imported condition classification; unverified.

    Aspartame: digestion, taste, metabolite dependencies and experimental signaling (2026-09-20) · lines 146–152

    AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Human carrier comparison, also including twelve noncarrier men. · source_derived_draft · unverified_draft

    ## aspartame-pku-carrier-kinetics Reduced metabolic reserve can change the response to a precursor source. After 34 mg/kg, twelve female PKU heterozygotes had higher peak phenylalanine than ten noncarrier females, 15.1 versus 8.95 micromol/dL. Model: Human carrier comparison, also including twelve noncarrier men. Limitations: Heterozygotes do not represent patients with biallelic PAH deficiency; the damaged male-baseline sentence in indexed abstract is not reconstructed. Evidence access: Primary abstract Plasma phenylalanine levels in phenylketonuric heterozygous and normal adults administered aspartame at 34 mg/kg body weight. · 1981 · https://pubmed.ncbi.nlm.nih.gov/7268794/ · DOI 10.1016/0300-483x(81)90108-6
    Complete structured claim and evidence

  6. Six adults consumed eight hourly 600 mg servings; phenylalanine rose modestly and plateaued after four to five servings within the reported normal postprandial range.

    Aspartame → Human plasma phenylalanine concentration source_derived_draftungraded
    Experimental context and source evidence
    availability_state
    biomarker_context Imported condition classification; unverified.
    evidence_access
    Primary abstract
    experimental_model
    Human beverage crossover; 4.8 g total over eight servings.
    limitations
    Small healthy-adult study; not a PKU population or a long-term trial.
    nutrient_topic
    Aspartame collection; species, compartment, exposure, co-substrates and manipulation remain explicit. · Aspartame
    plain_language
    Repeated exposure did not produce unlimited accumulation in this protocol.
    primary_references
    Effect of repeated ingestion of aspartame-sweetened beverage on plasma amino acid, blood methanol, and blood formate concentrations in normal adults. · 1989 · https://pubmed.ncbi.nlm.nih.gov/2566887/ · DOI 10.1016/0026-0495(89)90125-x
    trigger_kind
    biomarker_context Imported condition classification; unverified.

    Aspartame: digestion, taste, metabolite dependencies and experimental signaling (2026-09-20) · lines 106–112

    AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Human beverage crossover; 4.8 g total over eight servings. · source_derived_draft · unverified_draft

    ## aspartame-repeated-phenylalanine Repeated exposure did not produce unlimited accumulation in this protocol. Six adults consumed eight hourly 600 mg servings; phenylalanine rose modestly and plateaued after four to five servings within the reported normal postprandial range. Model: Human beverage crossover; 4.8 g total over eight servings. Limitations: Small healthy-adult study; not a PKU population or a long-term trial. Evidence access: Primary abstract Effect of repeated ingestion of aspartame-sweetened beverage on plasma amino acid, blood methanol, and blood formate concentrations in normal adults. · 1989 · https://pubmed.ncbi.nlm.nih.gov/2566887/ · DOI 10.1016/0026-0495(89)90125-x
    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.

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