A photoactivable natural product with broad antiviral activity against enveloped viruses including highly pathogenic coronaviruses

Abstract

The SARS-CoV-2 outbreak has highlighted the need for broad-spectrum antivirals against coronaviruses (CoVs). Here, pheophorbide a (Pba) was identified as a highly active antiviral molecule against HCoV-229E after bioguided fractionation of plant extracts. The antiviral activity of Pba was subsequently shown for SARS-CoV-2 and MERS-CoV, and its mechanism of action was further assessed, showing that Pba is an inhibitor of coronavirus entry by directly targeting the viral particle. Interestingly, the antiviral activity of Pba depends on light exposure, and Pba was shown to inhibit virus-cell fusion by stiffening the viral membrane as demonstrated by cryo-electron microscopy. Moreover, Pba was shown to be broadly active against several other enveloped viruses, and reduced SARS-CoV-2 and MERS-CoV replication in primary human bronchial epithelial cells. Pba is the first described natural antiviral against SARS-CoV-2 with direct photosensitive virucidal activity that holds potential for COVID-19 therapy or disinfection of SARS-CoV-2 contaminated surfaces.

A relevância da educação para a saúde coletiva

“…As células tumorais crescem mais rápido e, portanto, absorvem mais substâncias do ambiente externo, o que pode ajudar a aumentar a concentração intracelular do Fs [67]. Em 1912, Meyer-Betz demonstrou que a (HpD), é um composto isolado da hemoglobina, era um Fs muito poderoso com propriedades de localização tumoral [71,72].…”

Espécies do gênero Ocimum com atividades anticâncer: uma revisão

“…Em 1912, Meyer-Betz demonstrou que a (HpD), é um composto isolado da hemoglobina, era um Fs muito poderoso com propriedades de localização tumoral [71,72].…”

Could chlorophyllins improve the safety profile of beta-d-N4-hydroxycytidine versus N-hydroxycytidine, the active ingredient of the SARS-CoV-2 antiviral molnupiravir?

“… 11 In turn, this may initially deliver a more targeted antiviral approach that does not generate toxic by-products in the host cell. As other derivatives of chlorophyll α, such as pheophorbide α, are already recognised for their antiviral effect against SARS-CoV-2, 27 , 28 the varied protection afforded by these compounds suggests that chlorophyllins are likely to safely enhance the therapeutic efficacy of NAs. Unlike antioxidants, which do not possess antiviral properties, the broad-spectrum antiviral effects of chlorophyllins could act as an adjuvant, whereby delivery in combination with MOV may provide an enhanced antiviral effect via two entirely distinct mechanisms.…”