The Petasites hybridus CO2 Extract (Ze 339) Blocks SARS-CoV-2 Replication In Vitro

Efficacy and Safety of Phytotherapy and Anthroposophic Medicine in Seasonal Allergic Rhinitis: A Systematic Review

INTRODUCTION

Seasonal allergic rhinitis (SAR) is a common health condition that is associated with an increased risk for bronchial asthma. Besides conventional medicine, treatments from traditional, complementary and integrative medicine are widely used by individuals with SAR. This review aims to systematically summarize evidence on the efficacy, effectiveness, and safety of European/Western phytotherapy (PT) and medications from anthroposophic medicine (AM) in individuals with SAR.

METHODS

Four electronic databases were screened for clinical studies published between January 1990 and March 2023. The results were qualitatively synthesized and the study quality was assessed.

RESULTS

In total, 14 studies were included, 11 from European/Western PT and three from AM. About half of the studies were rated as being of sufficient quality. The most frequently studied plant was Petasites hybridus (butterbur), showing beneficial effects on immunological parameters, subjective symptoms, and nasal airflow. Beneficial immunological and clinical effects were also shown for an herbal preparation combining Citrus limonis (lemon) and Cydonia oblonga (quince). The medications examined by studies of sufficient quality were judged to be safe.

CONCLUSION

In summary, this systematic review highlights two herbal preparations, one from European/Western PT and one from AM, that appear to be promising options in the treatment of SAR.

Plant-derived compounds as potential leads for new drug development targeting COVID-19

COVID-19, which was first identified in 2019 in Wuhan, China, is a respiratory illness caused by a virus called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Although some patients infected with COVID-19 can remain asymptomatic, most experience a range of symptoms that can be mild to severe. Common symptoms include fever, cough, shortness of breath, fatigue, loss of taste or smell and muscle aches. In severe cases, complications can arise including pneumonia, acute respiratory distress syndrome, organ failure and even death, particularly in older adults or individuals with underlying health conditions. Treatments for COVID-19 include remdesivir, which has been authorised for emergency use in some countries, and dexamethasone, a corticosteroid used to reduce inflammation in severe cases. Biological drugs including monoclonal antibodies, such as casirivimab and imdevimab, have also been authorised for emergency use in certain situations. While these treatments have improved the outcome for many patients, there is still an urgent need for new treatments. Medicinal plants have long served as a valuable source of new drug leads and may serve as a valuable resource in the development of COVID-19 treatments due to their broad-spectrum antiviral activity. To date, various medicinal plant extracts have been studied for their cellular and molecular interactions, with some demonstrating anti-SARS-CoV-2 activity in vitro. This review explores the evaluation and potential therapeutic applications of these plants against SARS-CoV-2. This review summarises the latest evidence on the activity of different plant extracts and their isolated bioactive compounds against SARS-CoV-2, with a focus on the application of plant-derived compounds in animal models and in human studies.

Molecular networking unveils anti-SARS-CoV-2 constituents from traditionally used remedies

ETHNOPHARMACOLOGICAL RELEVANCE

Plants and fungi have a long tradition in ethnopharmacology for the treatment of infectious diseases including viruses. Many of these natural products have also been used to combat SARS-CoV-2 infections or symptoms of the post- and long-COVID form, owing to the scarcity of clinically approved therapeutics.

AIM OF THE STUDY

The ongoing threat posed by SARS-CoV-2, along with the rapidly evolving new variants, requires the development of new antiviral compounds. The aim of this study was to identify anti-SARS-CoV-2 herbal and fungal extracts used in traditional medicine against acute respiratory infection, inflammation, and related symptoms. Additionally, we sought to characterize their bioactive constituents.

MATERIALS AND METHODS

The antiviral activity and cell cytotoxicity of 179 herbal and fungal extracts were evaluated using two SARS-CoV-2 infection assays in Caco-2 cells. 19 plant extracts with and without anti-SARS-CoV-2 activity underwent detailed dereplication using molecular networking.

RESULTS

Extracts from Angelica sinensis (Oliv.) Diels roots, Annona squamosa L. seeds, Azadirachta indica A. Juss. fruits, Buddleja officinalis Maxim. flowers, Burkea africana Hook. bark and Clinopodium menthifolium (Host) Stace aerial parts showed a potent anti SARS-CoV-2 activity (IC50 < 5 μg/ml) with only moderate cytotoxicity (CC50 > 60 μg/ml, Caco-2). By performing the dereplication with a bioactivity-featured molecular network (MN) on the extract library level, rather than on the level of individual extracts, we could pinpoint compounds characteristic for active extracts. Thus, a straight-forward identification of potential anti-SARS-CoV-2 natural compounds was achieved prior to any fractionation or isolation efforts.

CONCLUSIONS

A sophisticated hyphenation of empirical knowledge with MS-based bioinformatics and automated compound annotation was applied to decipher the chemical space of the investigated extracts. The correlation with experimentally assessed anti-SARS-CoV-2 activities helped in predicting compound classes and structural elements relevant for the antiviral activities. Consequently, this accelerated the identification of constituents from the investigated mixtures with inhibitory effects against SARS-CoV-2.

Inhibition of SARS-CoV-2 infection and replication by Petasites hybridus CO2-extract (Ze 339)

BACKGROUND

The intensified search for low-threshold herbal anti-viral drugs would be of great advantage in prevention of early stages of infection. Since the SARS-CoV-2 Omicron variant has prevailed in western countries, the course has only been mild, but there are still no widely available drugs that can alleviate or shorten disease progression and counteract the development of Long-COVID. This study aimed to investigate the antiviral effects of a CO2-extract from Petasites hybridus (Ze 339).

METHODS

We analyzed the infection and replication rate of SARS-CoV-2 in primary normal human bronchial epithelial cells (NHBEs) using a GFP-expressing version of the wild-type SARS-CoV-2 virus and live cell imaging. Upon infection with a clinical isolate of the Omicron variant, viral RNA content was quantified, and plaque assays were performed. In addition, the human transcriptome was analyzed after 4- and 24-hours post infection using whole genome microarrays.

RESULTS

Ze 339 had a protective effect on primary airway epithelial cells during SARS-CoV-2 infection and impeded SARS-CoV-2 infection and replication in NHBE. Notably, Ze 339 inhibited the expression of infection-induced IFNA10 by 8.6-fold (p < 0.05) and additionally reduced a wide range of other interferons (IFNA6, IFNA7, IFNA8, IFNA21, IFNE, IFNW1).

CONCLUSION

Thereby, Ze 339 attenuated epithelial infection by SARS-CoV-2 and modeled the IFN response. In conclusion, this study highlights Ze 339 as a potential treatment option for COVID-19 that limits infection-associated cell intrinsic immune responses.

Bioactive natural products in COVID-19 therapy

The devastating COVID-19 pandemic has caused more than six million deaths worldwide during the last 2 years. Effective therapeutic agents are greatly needed, yet promising magic bullets still do not exist. Numerous natural products (cordycepin, gallinamide A, plitidepsin, telocinobufagin, and tylophorine) have been widely studied and play a potential function in treating COVID-19. In this paper, we reviewed published studies (from May 2021 to April 2022) relating closely to bioactive natural products (isolated from medicinal plants, animals products, and marine organisms) in COVID-19 therapy in vitro to provide some essential guidance for anti-SARS-CoV-2 drug research and development.