Natural Products as Potential Leads Against Coronaviruses: Could They be Encouraging Structural Models Against SARS-CoV-2?

Abstract

New coronavirus referred to SARS-CoV-2 has caused a worldwide pandemic (COVID-19) declared by WHO. Coronavirus disease 2019 (COVID-19) is an infectious disease with severe acute respiratory syndrome caused by coronavirus-2 (SARS-CoV-2). SARS-CoV-2 is akin to SARS-CoV, which was the causative agent of severe acute respiratory syndrome (SARS) in 2002 as well as to that of Middle East respiratory syndrome (MERS) in 2012. SARS-CoV-2 has been revealed to belong to Coronaviridiae family as a member of β-coronaviruses. It has a positive-sense single-stranded RNA with the largest RNA genome. Since its genomic sequence has a notable similarity to that of SARS-CoV, antiviral drugs used to treat SARS and MERS are now being also applied for COVID-19 treatment. In order to combat SARS-CoV-2, many drug and vaccine development studies at experimental and clinical levels are currently conducted worldwide. In this sense, medicinal plants and the pure natural molecules isolated from plants have been reported to exhibit significant inhibitory antiviral activity against SARS-CoV and other types of coronaviruses. In the present review, plant extracts and natural molecules with the mentioned activity are discussed in order to give inspiration to researchers to take these molecules into consideration against SARS-CoV-2.

Immunomodulatory Effects of Diterpenes and Their Derivatives Through NLRP3 Inflammasome Pathway: A Review

“…It is evident to release pro-inflammatory cytokines, including IL-6 and IL-1β through the NLRP3 inflammasome pathway (91). Many natural products and their derivatives, including diterpenes, have been found to act against human coronaviruses, such as SARS-CoV and the Middle East respiratory syndrome-related coronavirus (MERS-CoV) (92,93). Therefore, diterpenes and their derivatives acting through the NLRP3 inflammasome pathway might be a new hope to fight against the current pandemic outbreak.…”

Computer aided identification of potential SARS CoV-2 main protease inhibitors from diterpenoids and biflavonoids of Torreya nucifera leaves

“…Purohit and coworkers have found that polyphenols such as oolonghomobisflavan-A and theaflavin-3-O-gallate from the tea plant (Camellia sinensis L.) can act as effective SARS CoV-2 Mpro inhibitors (Bhardwaj et al, 2020). Apart from polyphenolic compounds, plant-derived terpenoid compounds are also found to inhibit the activity of Mpro (Orhan & Senol Deniz, 2020;Sayed et al, 2020;Wen et al, 2007). The leaves of the traditional medicinal plant Torreya nucifera contains eight well-known diterpenoids (18-hydroxyferruginol, hinokiol, ferruginol, 18-oxoferruginol, O-acetyl-18hydroxyferruginol, methyl dehydroabietate, isopimaric acid, kayadiol) and four biflavonoids (amentoflavone, bilobetin, ginkgetin, sciadopitysin) ( Figure 1) (Ryu et al, 2010).…”

Propolis and coronavirus disease 2019 (COVID-19): Lessons from nature

“…Compared to previous coronavirus epidemics, the contagiousness is higher, but the mortality decidedly lower compared to the severe acute respiratory syndrome (SARS) of 2002 and the Middle East respiratory syndrome (MERS) of 2012, both of them related with higher mortality (9.5% and 34.4%, respectively) [ 2 , 3 ]. Intensely, a series of translational studies for drug and vaccine development has been carried out worldwide with the aim of combating the SARS-Cov-2 [ 4 ]. In these lines, medicinal plants and the pure natural molecules isolated from plants has shown an important inhibitory antiviral activity against SARS-Cov-2 [ 4 ].…”

“…Intensely, a series of translational studies for drug and vaccine development has been carried out worldwide with the aim of combating the SARS-Cov-2 [ 4 ]. In these lines, medicinal plants and the pure natural molecules isolated from plants has shown an important inhibitory antiviral activity against SARS-Cov-2 [ 4 ]. From this clinical reasoning, the use of propolis as a possible complementary treatment in patients with SARS-Cov-2 should play an important role in this scenario.…”