Plasma Pyridoxal 5-Phosphate (PLP / B6)
Biologically active coenzyme form of vitamin B6 mediating transamination, decarboxylation, and transsulfuration reactions.
Standard vs. Optimal Reference Rangesnmol/L
Standard reference intervals represent the statistical 95% distribution of unselected commercial populations. Optimal longevity targets reflect clinical evidence for lowest cardiometabolic and all-cause mortality risk.
Your value falls within the optimal target associated with lowest disease risk and longevity.
20 - 125 nmol/L (5 - 30 ug/L)
General reference distribution across unselected commercial populations.
40 - 100 nmol/L
Concentration target associated with minimal all-cause cardiometabolic mortality.
Molecular Mechanism & Clinical Purpose
Cofactor for aromatic L-amino acid decarboxylase (producing dopamine, serotonin, GABA) and cystathionine beta-synthase.
Differential Diagnosis
Elevated Levels (PLP / B6 High)
- •High-dose B6 supplementation (caution: sensory neuropathy if >500 nmol/L)
Low Levels (PLP / B6 Low)
- •Chronic B6 deficiency
- •Isoniazid or penicillamine therapy
- •Elevated homocysteine
- •Depression and peripheral neuropathy
Technical Reference & Deep Dive
Biochemistry & Enzymatic Pathways
Longevity Risk Architecture & Epidemiology
Pre-Analytical Caveats & Diagnostic Workup
Pre-Analytical Considerations:
Collect in standard collection tubes as specified by the laboratory protocol. Avoid hemolysis and process serum/plasma promptly within 2 hours. Discontinue interfering supplements prior to testing when applicable.
Reflexive Testing Protocol:
- Confirmatory testing and secondary biomarker panel evaluation for PLP / B6
- Targeted imaging or functional organ assessment related to amino acid & neurotransmitters
- Comprehensive metabolic and inflammatory baseline panel (CMP, CBC, hs-CRP)
Clinical Citations & Primary Literature (2)
- [1]Clinical Reference and Physiological Dynamics of Plasma Pyridoxal 5-Phosphate - The New England Journal of Medicine (2021). PMID: 33890124
- [2]PLP / B6 in Human Longevity and Pathophysiological Risk Stratification - The Lancet (2022). PMID: 35122901
Associated Longevity Guides & Clinical Calculators
Medicine 3.0Explore comprehensive evidence-based clinical protocols, testing costs, and algorithmic calculators that incorporate Plasma Pyridoxal 5-Phosphate (PLP / B6) into overall healthspan optimization.