Abstract
As viral infections are an increasing threat to human societies, the need for new
therapeutic strategies is becoming even more obvious. As no vaccine is available for
COVID-19, the development of directly acting antiviral agents and preventive strategies
have to be considered. Nature provides a huge reservoir of anti-infectious compounds,
from which we can deduce innovative ideas, therapies, and products. Anti-adhesive
natural products interact with the receptor-mediated recognition and early interaction
of viruses with the host cells, leading to a reduced internalisation of the virus
and reduced infections (e.g., procyanidin-B-2-di-O-gallate against influenza and herpes
virus). Lignans like podophyllotoxin and bicyclol show strong antiviral activities
against different viruses, and essential oils can directly interact with viral membranes
and reduce the hostʼs inflammatory responses (e.g., 1,8-cineol). Echinacea extracts stimulate the immune system, and bioavailable alkamides are key players
by interacting with immunomodulating cannabinoid receptors. COVID-19 and SARS-CoV-2
infections have, in part, successfully been treated in China by preparations from
traditional Chinese medicine and, while it is too early to draw conclusions, some
promising data are available. There is huge potential, but intensified research is
needed to develop evidence-based medicines with a clearly defined chemical profile.
Intensified research and development, and therefore funding, are needed for exploiting
natureʼs reservoir against viral infections. Combined action for basic research, chemistry,
pharmacognosy, virology, and clinical studies, but also supply chain, sustainable
sourcing, and economic aspects have to be considered. This review calls for intensified
innovative science on natural products for the patients and for a healthier world!
Key words
COVID - Coronaviridae -
Echinacea
- Asteraceae - virus - tannins - lignans - anti-adhesion - immune system - phytotherapy