Efficacy of broccoli and glucoraphanin in COVID-19: From hypothesis to proof-of-concept with three experimental clinical cases

• Main Authors: Jean Bousquet, Vincent Le Moing, Hubert Blain, Wienczyslawa Czarlewski, Torsten Zuberbier, Rafael de la Torre, Nieves Pizarro Lozano, Jacques Reynes, Anna Bedbrook, Jean-Paul Cristol, Alvaro A. Cruz, Alessandro Fiocchi, Tari Haahtela, Guido Iaccarino, Ludger Klimek, Piotr Kuna, Erik Melén, Joaquim Mullol, Boleslaw Samolinski, Arunas Valiulis, Josep M. Anto
• Format: Article
• Language: English
• Published: Elsevier 2021-01-01
• Series: World Allergy Organization Journal
• Subjects: COVID-19; Nrf2; Broccoli; Cough challenge; TRPA1; TRPV1
• Online Access: http://www.sciencedirect.com/science/article/pii/S1939455120304014

COVID-19 is described in a clinical case involving a patient who proposed the hypothesis that Nuclear factor (erythroid-derived 2)-like 2 (Nrf2)-interacting nutrients may help to prevent severe COVID-19 symptoms. Capsules of broccoli seeds containing glucoraphanin were being taken before the onset of SARS-CoV-2 infection and were continued daily for over a month after the first COVID-19 symptoms. They were found to reduce many of the symptoms rapidly and for a duration of 6–12 h by repeated dosing. When the patient was stable but still suffering from cough and nasal obstruction when not taking the broccoli capsules, a double-blind induced cough challenge confirmed the speed of onset of the capsules (less than 10 min). A second clinical case with lower broccoli doses carried out during the cytokine storm confirmed the clinical benefits already observed. A third clinical case showed similar effects at the onset of symptoms. In the first clinical trial, we used a dose of under 600 μmol per day of glucoraphanin. However, such a high dose may induce pharmacologic effects that require careful examination before the performance of any study. It is likely that the fast onset of action is mediated through the TRPA1 channel. These experimental clinical cases represent a proof-of-concept confirming the hypothesis that Nrf2-interacting nutrients are effective in COVID-19. However, this cannot be used in practice before the availability of further safety data, and confirmation is necessary through proper trials on efficacy and safety.