Related Experiment Video
Updated: Jul 6, 2025
High-throughput Screening for Broad-spectrum Chemical Inhibitors of RNA Viruses
Published on: May 5, 2014
Plant extracts modulate cellular stress to inhibit replication of mouse Coronavirus MHV-A59
Karol Prieto1, Cindy Arévalo1, Paola Lasso1
1Grupo de Inmunobiología y Biología Celular, Departamento de Microbiología, Pontificia Universidad Javeriana. Bogotá, Colombia.
Abstract:
The Covid-19 infection outbreak led to a global epidemic, and although several vaccines have been developed, the appearance of mutations has allowed the virus to evade the immune response. Added to this is the existing risk of the appearance of new emerging viruses. Therefore, it is necessary to explore novel antiviral therapies. Here, we investigate the potential in vitro of plant extracts to modulate cellular stress and inhibit murine hepatitis virus (MHV)-A59 replication. L929 cells were treated with P2Et (Caesalpinia spinosa) and Anamu SC (Petiveria alliacea) plant extracts during infection and virus production, ROS (reactive oxygen species), UPR (unfolded protein response), and autophagy were assessed. P2Et inhibited virus replication and attenuated both ROS production and UPR activation induced during infection. In contrast, the sustained presence of Anamu SC during viral adsorption and replication was required to inhibit viral infection, tending to induce pro-oxidant effects, and increasing UPR gene expression. Notably, the loss of the PERK protein resulted in a slight decrease in virus yield, suggesting a potential involvement of this UPR pathway during replication. Intriguingly, both extracts either maintained or increased the calreticulin surface exposure induced during infection. In conclusion, our findings highlight the development of antiviral natural plant extracts that differentially modulate cellular stress.
Insights
Novel plant extracts show potential as antiviral therapies by modulating cellular stress and inhibiting viral replication. Caesalpinia spinosa extract reduced viral load and cellular stress, while Petiveria alliacea extract required sustained presence to inhibit infection.
Area of Science:
- Virology
- Cellular Biology
- Natural Product Chemistry
Background:
- Emerging viral threats necessitate novel antiviral strategies beyond vaccines.
- Viral mutations can evade immune responses, highlighting the need for alternative therapies.
- Plant-derived compounds offer a promising avenue for developing new antiviral treatments.
Purpose of the Study:
- To investigate the in vitro antiviral potential of Caesalpinia spinosa (P2Et) and Petiveria alliacea (Anamu SC) extracts.
- To assess the effects of these plant extracts on cellular stress responses during viral infection.
- To determine the impact of extracts on murine hepatitis virus (MHV)-A59 replication.
Main Methods:
- L929 cells were infected with MHV-A59 and treated with P2Et and Anamu SC extracts.
- Assessed viral replication, reactive oxygen species (ROS) production, unfolded protein response (UPR), and autophagy.
- Investigated the role of PERK protein in viral replication and calreticulin surface exposure.
Main Results:
- P2Et inhibited MHV-A59 replication and attenuated infection-induced ROS production and UPR activation.
- Anamu SC required sustained presence to inhibit viral infection, induced pro-oxidant effects, and increased UPR gene expression.
- PERK protein loss slightly decreased virus yield, and both extracts maintained or increased calreticulin surface exposure.
Conclusions:
- Plant extracts differentially modulate cellular stress pathways during viral infection.
- Caesalpinia spinosa extract demonstrates significant antiviral activity by reducing viral replication and cellular stress.
- Petiveria alliacea extract shows antiviral effects but with distinct mechanisms involving UPR modulation.
