Sulforaphane: from death rate heterogeneity in countries to candidate for prevention of severe COVID-19

Antó

Czarlewski³

et al. 2020

Preprint

Self Cite

Large differences in COVID-19 death rates exist between countries and between regions of the same country. Some very low death rate countries such as Eastern Asia, Central Europe or the Balkans have a common feature of eating large quantities of fermented foods. Although biases exist when examining ecological studies, fermented vegetables or cabbage were associated with low death rates in European countries. SARS-CoV-2 binds to its receptor, the angiotensin converting enzyme 2 (ACE2). As a result of SARS-Cov-2 binding, ACE2 downregulation enhances the angiotensin II receptor type 1 (AT1R) axis associated with oxidative stress. This leads to insulin resistance, lung and endothelial damage, two severe outcomes of COVID-19. The nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is the most potent antioxidant in humans and can block the AT1R axis. Cabbage contains precursors of sulforaphane, the most active natural activator of Nrf2. Fermented vegetables contain many lactobacilli, which are also potent Nrf2 activators. It is proposed that fermented cabbage is a proof-of-concept of dietary manipulations that may enhance Nrf2-associated antioxidant effects helpful in mitigating COVID-19 severity.

Section: Angiotensin-converting Enzyme 2 (Ace2) and Covid-19mentioning

confidence: 99%

“…Nrf2 may be involved in diseases associated with insulin-resistance. 57,[70][71][72] Nrf2 activity declines with age, making the elderly more susceptible to oxidative stress-mediated diseases. 73 Nrf2 is involved in the protection against lung 74 or endothelial damage.…”

mentioning

confidence: 99%

Cabbage and fermented vegetables: from death rate heterogeneity in countries to candidates for mitigation strategies of severe COVID-19

Antó

Czarlewski³

et al. 2020

Preprint

Self Cite

“…AT 1 R is involved in most Angiotensin II effects, including oxidative stress generation, pro-inflammatory, pro-fibrotic effects in the respiratory system, endothelial damage and insulin resistance. 21,22 SARS-CoV-2 binds to and downregulates ACE-2, enhancing the AT 1 R axis 23 , likely to be associated with insulin resistance 24,25 but also to severe outcomes of COVID-19.…”

Section: Angiotensin-converting Enzyme 2 (Ace2) and Covid-19mentioning

confidence: 99%

“…Kimchi, when fermented for a long time, reduces insulin intolerance to a greater extent than fresh kimchi 33 , indicating that newly formed products during fermentation are important. In particular, Kimchi from cabbage and Chinese cabbage contains several glucosinolates 1,42,43 that can be transformed in sulforaphanes either in the plant itself or by the human microbiome 24 . Sulforaphanes were suggested to be effective in diseases associated with insulin resistance 1,[44][45][46] .…”

Section: Effects Of Fermented Vegetables On Insulin Resistancementioning

confidence: 99%

“…Fermented vegetables contain a high content of Lactobacillus that can activate Nrf2 and impact on the microbiome. Nrf2 may be involved in diseases associated with insulin-resistance 24,[56][57][58] and may have a role in COVID-19. 59 Sulforaphane and LABs both have the ability to reduce insulin resistance.…”

Section: Proposed Mechanisms Of Action Of Kimchi and Fermented Vegetamentioning

confidence: 99%

See 1 more Smart Citation

Kimchi and Asian fermented vegetables: candidates for the partial control of the COVID-19 pandemic

Antó

Czarlewski³

et al. 2020

Preprint

Self Cite

To the Editor, A COVID-19 epidemic started in China and then disseminated to other Asian countries before becoming a pandemic. It appears that the pandemic has so far resulted in proportionately fewer deaths in China and most Eastern Asian countries. Many reasons can explain this picture. 1 One of them is the type of diet in the low mortality countries. 2 This paper is the sixth of a series attempting to understand the role of diet in the differences of COVID-19 death rates between and within countries with the aim to identify potential preventive measures against COVID-19. The concept paper 2 was followed by two ecological studies comparing death rates in European countries and the consumption of vegetables or fermented foods. 3,4 We then proposed that sulforaphane from cruciferous vegetables 1 and lactobacilli from fermented foods (submitted) were possibly involved in the reduction of insulin resistance in COVID-19. It is noteworthy that fermented foods are largely used in Asia. 5,6 It is therefore important to check whether some commonly eaten fermented foods in these countries may explain geographic differences in COVID-19. Kimchi will be used as a model of fermented cabbage. Geographic differences in COVID-19 death rates When comparing death rates, large differences exist between and within countries and the evolution of the pandemic differs largely between countries (Figure 1). As the temporal dynamic of the pandemic may have changed the geographical patterns observed in our previous analyses, 2 we focus on the more recent mortality trends. Although there are many pitfalls in analyzing death rates for COVID-19, 2 the evolution of death rates

Cabbage and fermented vegetables: From death rate heterogeneity in countries to candidates for mitigation strategies of severe COVID‐19

Haahtela

Fonseca

et al. 2020

Allergy

Self Cite

Large differences in COVID‐19 death rates exist between countries and between regions of the same country. Some very low death rate countries such as Eastern Asia, Central Europe or the Balkans have a common feature of eating large quantities of fermented foods. Although biases exist when examining ecological studies, fermented vegetables or cabbage were associated with low death rates in European countries. SARS‐CoV‐2 binds to its receptor, the angiotensin converting enzyme 2 (ACE2). As a result of SARS‐Cov‐2 binding, ACE2 downregulation enhances the angiotensin II receptor type 1 (AT 1 R) axis associated with oxidative stress. This leads to insulin resistanceas well as lung and endothelial damage, two severe outcomes of COVID‐19. The nuclear factor (erythroid‐derived 2)‐like 2 (Nrf2) is the most potent antioxidant in humans and can block the AT 1 R axis. Cabbage contains precursors of sulforaphane, the most active natural activator of Nrf2. Fermented vegetables contain many lactobacilli, which are also potent Nrf2 activators. Three examples are given: Kimchi in Korea, westernized foods and the slum paradox. It is proposed that fermented cabbage is a proof‐of‐concept of dietary manipulations that may enhance Nrf2‐associated antioxidant effects helpful in mitigating COVID‐19 severity.