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

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 have been 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 resistance as 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 in particular 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: 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.Peer reviewe

Nrf2-interacting nutrients and COVID-19 : time for research to develop adaptation strategies

There are large between- and within-country variations in COVID-19 death rates. Some very low death rate settings such as Eastern Asia, Central Europe, the Balkans and Africa have a common feature of eating large quantities of fermented foods whose intake is associated with the activation of the Nrf2 (Nuclear factor (erythroid-derived 2)-like 2) anti-oxidant transcription factor. There are many Nrf2-interacting nutrients (berberine, curcumin, epigallocatechin gallate, genistein, quercetin, resveratrol, sulforaphane) that all act similarly to reduce insulin resistance, endothelial damage, lung injury and cytokine storm. They also act on the same mechanisms (mTOR: Mammalian target of rapamycin, PPAR gamma:Peroxisome proliferator-activated receptor, NF kappa B: Nuclear factor kappa B, ERK: Extracellular signal-regulated kinases and eIF2 alpha:Elongation initiation factor 2 alpha). They may as a result be important in mitigating the severity of COVID-19, acting through the endoplasmic reticulum stress or ACE-Angiotensin-II-AT(1)R axis (AT(1)R) pathway. Many Nrf2-interacting nutrients are also interacting with TRPA1 and/or TRPV1. Interestingly, geographical areas with very low COVID-19 mortality are those with the lowest prevalence of obesity (Sub-Saharan Africa and Asia). It is tempting to propose that Nrf2-interacting foods and nutrients can re-balance insulin resistance and have a significant effect on COVID-19 severity. It is therefore possible that the intake of these foods may restore an optimal natural balance for the Nrf2 pathway and may be of interest in the mitigation of COVID-19 severity

Sanitary status of slovenian indigenous grapevine cultivar Refosk

Sanitary status of visually selected and nonselected indigenous grapevine cultivar 'Refosk' (Vitis vinifera L. cv. 'Refosk') was evaluated. Nine viruses were tested by ELISA: Nepoviruses Grapevine fanleaf virus (GFLV) and Arabis mosaic virus (ArMV), Closteroviruses Grapevine leafroll associated viruses 1 (GLRaV-1), 2 (GLRaV-2), 3 (GLRaV-3), and 6 (GLRaV-6), Grapevine fleck virus (GFkV) and Vitiviruses Grapevine virus A (GVA) and Grapevine virus B (GVB). All viruses except ArMV and GVB were detected. The vines of cv. ‘Refosk’ passing the visual selection were 50 % free of tested viruses in comparison to only 24 % virus-free vines of non-visually selected material. Visually selected plants revealed the highest incidence of virus GLRaV- 1 (37 %) and in addition to that a 15 % incidence of rugose wood (RW) disease symptoms

Genetic variability within RNA2 of Grapevine fanleaf virus

International audienceThe genetic variability of Grapevine fanleaf virus (GFLV) was assessed within RNA2 of nine isolates from Vitis vinifera cv. Volovnik in a vineyard in Slovenia by immunocapture (IC)-reverse transcription (RT)-polymerase chain reaction (PCR)-restriction length fragment polymorphism (RFLP), followed by cloning and sequencing. Four, one, and nine distinct StyI restrictotypes were identified in the 2AHP, 2BMP, and 2CCP genes, respectively, by IC-RT-PCR-RFLP. Each isolate had a specific StyI RFLP profile across the three RNA2-encoded genes. Sequence analysis of cloned RNA2 ORF amplicons obtained by IC-RT-PCR showed mixed infection in four of the nine isolates and a slightly higher nucleotide variability in the 2AHP and 2CCP genes relative to the 2BMP gene. Also, gene 2AHP, unlike genes 2BMP and 2CCP, had a variable size (765-774 nucleotides) and high amino acid diversity (up to 15%). In addition, a recombination event was identified at nucleotide position 220-225 of gene 2AHP in three of the nine isolates. No clear association was apparent between symptomatology and restrictotype composition, phylogenetic clustering, or occurrence of recombination. This study provides new insights into the genetic diversity of GFLV