Insights into estrogen impact in oral health & microbiome in COVID-19 Original paper
Researched by:
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Dr. Umar
ID
Dr. Umar
Read MoreClinical Pharmacist and Clinical Pharmacy Master’s candidate focused on antibiotic stewardship, AI-driven pharmacy practice, and research that strengthens safe and effective medication use. Experience spans digital health research with Bloomsbury Health (London), pharmacovigilance in patient support programs, and behavioral approaches to mental health care. Published work includes studies on antibiotic use and awareness, AI applications in medicine, postpartum depression management, and patient safety reporting. Developer of an AI-based clinical decision support system designed to enhance antimicrobial stewardship and optimize therapeutic outcomes.
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Dr. Umar
Read More
Researched by:
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Dr. Umar
ID
Dr. Umar
Read More
Microbiome Signatures identifies and validates condition-specific microbiome shifts and interventions to accelerate clinical translation. Our multidisciplinary team supports clinicians, researchers, and innovators in turning microbiome science into actionable medicine.
Divine Aleru
Location
Mexico
Sample Site
Saliva
Species
Homo sapiens
What was studied?
This study examined how estrogen levels influence oral health, inflammatory cytokines, ACE2 expression, and the oral microbiome in COVID-19, with the goal of identifying microbiome signatures linked to hormonal status during SARS-CoV-2 infection. This focus on estrogen’s effects grounds the inquiry in a key clinical concept: estrogen–oral microbiome interactions in COVID-19. The authors compared premenopausal women, postmenopausal women, and men to determine whether hormonal differences shape viral load, mucosal immunity, and microbial ecology. Using 16S rRNA sequencing, cytokine profiling, and ACE2 immunofluorescence analysis, the study mapped how microbial populations such as Prevotella, Leptotrichia, Alloprevotella, Tannerella, Porphyromonas endodontalis, and Neisseria perflava fluctuate across oral-health and hormonal gradients.
Who was studied?
The study enrolled 60 unvaccinated adults infected with SARS-CoV-2: 20 premenopausal women (ages 18–45), 18 postmenopausal women (>45 years), and 22 men (>18 years). Participants underwent oral examinations, saliva and blood sampling, cytokine assays, estrogen measurements, and oral microbiome sequencing. Exclusions included smokers, recent antibiotic/probiotic use, autoimmune disease, cancer, HIV/HBV/HCV, hormonal therapy, or recent oral surgery. This yielded a carefully filtered population reflecting natural hormonal variation without exogenous immune or microbial confounders.
Most important findings
The study revealed distinct microbiome and inflammatory signatures tied to estrogen levels, oral health, and viral load. Premenopausal women—those with the highest estrogen—showed higher lingual ACE2 expression but lower viral loads and healthier oral microbial profiles. Postmenopausal women and men exhibited worse oral health, higher oral proinflammatory cytokines, and microbial communities enriched in pathogenic taxa.
Key microbial associations (log₂ fold-change values from study):
| Clinical Comparison | Microbial Signatures | Direction | Notes |
|---|---|---|---|
| Premenopausal vs. Postmenopausal | Prevotella melaninogenica (26.68), Haemophilus (23.99), Alloprevotella (7.92) | ↑ Premenopausal | Commensal/pathobiont balance linked to estrogen |
| Poor vs. Adequate Oral Health | Leptotrichia (-18.74), Tannerella (-17.08), Clostridiales (-2.88) | ↑ Poor | Classic periodontal dysbiosis signature |
| Adequate Oral Health | Neisseria perflava (26.70) | ↑ Adequate | Commensal marker of oral health |
| High Viral Load | P. nanceiensis (19.60), P. melaninogenica (21.45), Alloprevotella (23.50), Porphyromonas endodentalis (21.97) | ↑ High VL | Pathogenic, inflammation-driven profile |
Key implications
The findings underscore an estrogen-linked protective axis in the oral cavity during COVID-19, where higher estrogen aligns with reduced viral load, healthier microbiome patterns, and lower inflammatory cytokines. Postmenopausal women and men exhibit microbial signatures consistent with periodontal dysbiosis, including Leptotrichia, Tannerella, and Porphyromonas, which may worsen mucosal integrity and promote viral persistence. For clinicians, this highlights the potential value of integrating hormonal status, oral health screening, and microbiome-informed biomarkers into risk stratification for respiratory viral infections. These microbial signatures may inform the development of predictive microbiome panels for COVID-19 prognosis or broader inflammatory disease susceptibility.
Citation
Bayardo-González R, Peña-Rodríguez M, Pereira-Suárez AL, Rubio-Sánchez AX, García-Chagollán M, Valenzuela-Orozco DN, et al. Insights into estrogen impact in oral health & microbiome in COVID-19.BMC Microbiology. 2024;24:32. doi:10.1186/s12866-023-03149-5