# Proteomics and Metabolomics Profiles of Unvaccinated Nonagenarian Patients with Severe SARS-CoV‑2 Infection

**Authors:** Mauricio Quiñones-Vega, Patricia Sosa-Acosta, Jéssica de Siqueira Guedes, Natália Pinto de Almeida, Mateus V de Castro, Moníze V. R. Silva, Luiz P. Dell’Aquila, Álvaro Razuk-Filho, Pedro B. Batista-Júnior, Mayana Zatz, Fábio César Sousa Nogueira, Gilberto Barbosa Domont

PMC · DOI: 10.1021/acs.jproteome.5c00251 · Journal of Proteome Research · 2025-09-25

## TL;DR

This study examines blood protein and metabolite profiles in unvaccinated elderly patients with severe COVID-19 to identify markers of disease severity and recovery.

## Contribution

The study identifies specific lipid-related proteins and metabolites as potential severity markers in unvaccinated nonagenarians with severe SARS-CoV-2 infection.

## Key findings

- Nonsurviving patients showed reduced abundance of lipid-related proteins and metabolites like APOH and phosphatidylethanolamine.
- Recovered patients exhibited persistent immune alterations including acute phase response and altered sphingolipids and phospholipids.
- The multiomics approach reveals molecular signatures predictive of severity and recovery in elderly SARS-CoV-2 patients.

## Abstract

The mortality rate of COVID-19 increases significantly
in patients
over the age of 90, although some elderly people in this category
have experienced mild disease or have been asymptomatic. In this context,
we aim to analyze the plasma proteomic and metabolomic profiles of
unvaccinated nonagenarian patients who had severe manifestations of
COVID-19 and either recovered or died and compare them with noninfected
control subjects. Compared with healthy individuals, nonsurviving
patients showed a reduced abundance of specific lipid-related proteins
and metabolites, including APOH, APOC1, LCAT, 7-α-25-dihydroxycholesterol,
7-dehydrocholesterol, and phosphatidylethanolamine, which may serve
as indicative markers of severity. Acute phase response, complement
activation, and sphingolipids and phospholipids remain altered in
recovered patients, indicating possible persistent effects of COVID-19.
This study employs a multiomics approach to unveil key immune alterations
in unvaccinated nonagenarians, shedding light on molecular signatures
that may serve as predictive markers for disease severity and recovery
in the elderly population.

## Linked entities

- **Proteins:** APOH (apolipoprotein H), APOC1 (apolipoprotein C1), LCAT (lecithin-cholesterol acyltransferase)
- **Chemicals:** 7-α-25-dihydroxycholesterol (PubChem CID 11954197), 7-dehydrocholesterol (PubChem CID 172), phosphatidylethanolamine (PubChem CID 5327011)
- **Diseases:** COVID-19 (MONDO:0100096)

## Full-text entities

- **Genes:** APOC1 (apolipoprotein C1) [NCBI Gene 341] {aka APOC1B, Apo-CI, ApoC-I, apo-CIB, apoC-IB}, APOH (apolipoprotein H) [NCBI Gene 350] {aka B2G1, B2GP1, BG}, LCAT (lecithin-cholesterol acyltransferase) [NCBI Gene 3931]
- **Diseases:** COVID-19 (MESH:D000086382), died (MESH:D003643)
- **Chemicals:** phospholipids (MESH:D010743), 7-alpha-25-dihydroxycholesterol (-), 7-dehydrocholesterol (MESH:C016705), lipid (MESH:D008055), phosphatidylethanolamine (MESH:C483858), sphingolipids (MESH:D013107)
- **Species:** Homo sapiens (human, species) [taxon 9606]

## Full text

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## Figures

5 figures with captions in the complete paper: https://tomesphere.com/paper/PMC12604035/full.md

## References

59 references — full list in the complete paper: https://tomesphere.com/paper/PMC12604035/full.md

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Source: https://tomesphere.com/paper/PMC12604035