Summary
| Direction in Long COVID | ↓ Reduced — lower than in the comparison group |
|---|---|
| Category | Metabolic |
| Also described as | Amino acid |
| Compared against | HC, R (healthy controls, recovered individuals without persistent symptoms) |
| Associated symptoms | Amino acid metabolism impairment |
| Test type | Blood test (serum / plasma / whole blood) |
| Source | Saito et al. 2024 — doi:10.3389/fimmu.2024.1341843 |
| Condition atlas | Long COVID Biomarker Atlas |
Trials, interventions and tests
In clinical-trial registrations this marker maps to the outcome term Aspartate aminotransferase (ASAT) (5 registered trials use a matching outcome measure).
Clinical trials using Aspartate as an outcome
- NCT03496961: Yan Nian Jiu Zhuan Fa Improve Chronic Fatigue Syndromes (Unknown)
Outcome measure: Neuropeptide Y - NCT05890534: Pycnogenol® in Post-COVID-19 Condition (Completed)
Outcome measure: Aspartate aminotransferase (ASAT) - NCT07278206: Brain Stimulation in Long COVID (Recruiting)
Outcome measure: Magnetic Resonance Spectroscopy (MRS) - NCT04482595: BIO 300 Oral Suspension in Previously Hospitalized Long COVID Patients (Unknown)
Outcome measure: Change in Clinical Laboratory Values for Serum Enzymes - NCT07357688: The Effect of Acupuncture Therapy on Cognitive Function in Post-COVID-19 Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (Not Yet Recruiting)
Outcome measure: The change in level of N-acetylaspartate(NAA)at each hippocampus from baseline to the end of 8 weeks.
Interventions studied alongside this marker
Hypothesis-generating links from trial outcome usage and literature co-occurrence. Not treatment recommendations.
- Repetitive Transcranial Magnetic Stimulation — 1 trial, 6 PubMed co-citations
e.g. Exploration of NMDA and GABA receptor-mediated plasticity induced by 10-Hz repetitive transcranial magnetic… - Acupuncture — 1 trial, 6 PubMed co-citations
e.g. Evaluation of electroacupuncture acupoint selection's potential in the treatment of inflammatory bowel…
Also sold as a nutrient or supplement
Aspartate (amino acid). Often studied as magnesium or mineral aspartate complexes. This tag means the analyte is also available orally; it is not a product endorsement and a low or high level does not by itself justify supplementation.
Related Metabolic markers in Long COVID
- Sarcosine ↓
- Asparagine ↓
- Serine ↓
- Glutamine ↓
- ATP (plasma) ↓
- Arginine ↓
- Histidine ↓
- TCA cycle intermediates ↑
Full list: Long COVID Biomarker Atlas.
Frequently asked questions
Is Aspartate high or low in Long COVID?
Reduced. Studies summarised in the OSMF atlas report lower Aspartate in Long COVID than in healthy controls, recovered individuals without persistent symptoms. Source: Saito et al. 2024.
What symptoms is Aspartate associated with in Long COVID?
The cited literature associates this marker with Amino acid metabolism impairment. These are population-level associations and do not mean the marker causes the symptoms.
Which test measures Aspartate?
It is measured as a blood test (serum / plasma / whole blood). Many of the cited studies used research-grade assays, so clinical availability may vary.
Is one abnormal Aspartate result diagnostic of Long COVID?
No. No single biomarker is diagnostic of Long COVID. Aspartate findings come from group comparisons, overlap considerably between patients and controls, and vary with study design, timing and comparison group. A result should be interpreted by a clinician alongside symptoms, history and other tests.
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Last reviewed: 2026-06-29 · Page generated from long-covid.json · Browse: Long COVID atlas · Biomarker Index · All marker pages
Disclaimer: This page is an educational synthesis of published, peer-reviewed research and is not medical advice. Biomarker findings vary across studies with case definitions, comparison groups, timing and assay methods. Direction of change reflects the predominant finding in the cited source and does not establish a diagnostic threshold. Discuss any test result with a qualified clinician.