ArticleMedical hypotheses2021
Does serotonin deficiency lead to anosmia, ageusia, dysfunctional chemesthesis and increased severity of illness in COVID-19?
Article in Medical hypotheses, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 16 papers.
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Who cites it
16 citing papers in PubMed, 32 citations in OpenAlex.
- Psychological and Biochemical Effects of an Online Pilates Intervention in Pregnant Women during COVID-19: A Randomized Pilot Study.International journal of environmental research and public health · 2022Trial
- Disruptions in serotonin- and kynurenine pathway metabolism in post-COVID: biomarkers and treatment.Frontiers in neurology · 2025Article
- Precision nutrition to reset virus-induced human metabolic reprogramming and dysregulation (HMRD) in long-COVID.NPJ science of food · 2024Review
- Article
- Treatment of 95 post-Covid patients with SSRIs.Scientific reports · 2023Article
- Could melatonin have a potential adjuvant role in the treatment of the lasting anosmia associated with COVID-19? A review.International journal of developmental neuroscience : the official journal of the International Society for Developmental Neuroscience · 2022Review
- The Role of Tryptophan Metabolites in Neuropsychiatric Disorders.International journal of molecular sciences · 2022Review
- Severe COVID-19 Is Characterised by Perturbations in Plasma Amines Correlated with Immune Response Markers, and Linked to Inflammation and Oxidative Stress.Metabolites · 2022Article
- Unbalanced IDO1/IDO2 Endothelial Expression and Skewed Keynurenine Pathway in the Pathogenesis of COVID-19 and Post-COVID-19 Pneumonia.Biomedicines · 2022Review
- Review
- Mechanisms and clinical evidence to support melatonin's use in severe COVID-19 patients to lower mortality.Life sciences · 2022Review
- Selective serotonin reuptake inhibitors: New hope in the fight against COVID-19.Frontiers in pharmacology · 2022Review
- Ongoing Use of SSRIs Does Not Alter Outcome in Hospitalized COVID-19 Patients: A Retrospective Analysis.Journal of clinical medicine · 2021Article
- Deregulated kynurenine metabolism - An alternate hypothesis for COVID-19 associated anosmia.Medical hypotheses · 2021Article
- Deficient synthesis of melatonin in COVID-19 can impair the resistance of coronavirus patients to mucormycosis.Medical hypotheses · 2021Article
- TRP channels in COVID-19 disease: Potential targets for prevention and treatment.Chemico-biological interactions · 2021Review
Corrections and comments
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Authors and funding
1 author at 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Different mechanisms forwarded to understand anosmia and ageusia in coronavirus patients are not adequate to explain reversible anosmia and ageusia, which are resolved quickly. In addition, the reason behind the impaired chemesthetic sensations in some coronavirus patients remains unknown. In the present paper it is proposed that SARS-CoV-2 patients suffer from depletion of tryptophan, as ACE2, a key element in the process of absorption of tryptophan from the food, is significantly reduced in the patients as coronavirus uses ACE2 as the receptor to enter the host cells. The tryptophan depletion leads to a deficit of serotonin (5-HT) in SARS-COV-2 patients because tryptophan is the precursor in the synthesis of 5-HT. Such 5-HT deficiency can explain anosmia, ageusia and dysfunctional chemesthesis in COVID-19, given the fact that 5-HT is an important neuromodulator in the olfactory neurons, taste receptor cells and transient receptor potential channels (TRP channels) involved in chemesthesis. In addition, 5-HT deficiency worsens silent hypoxemia and depresses hypoxic pulmonary vasoconstriction leading to increased severity of the disease. Also, the levels of anti-inflammatory melatonin (synthesized from 5-HT) and nicotinamide adenine dinucleotide (NAD
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