Can anisodamine be a potential substitute for high-dose atropine in cases of organophosphate poisoning?

A Review on the Chemical Properties, Plant Sources, Anti-shock Effects, Pharmacokinetics, Toxicity, and Clinical Applications of Anisodamine

Alkaloids are natural products that occur widely in many herbal plants. Anisodamine, widely present in the Solanaceae family, is an alkaloid extracted from the roots of the Anisodus tanguticus Maxim. It is an antagonist to M-choline receptors and exhibits diverse pharmacological effects, such as cholinolytic effect, calcium antagonist effect, anti-oxygenation effect. Anisodamine, a prominent constituent of the tropine alkaloid family, exhibits a range of pharmacological effects akin to those of atropine and scopolamine. owing to its low toxicity and moderate efficacy in clinical to wide applications, especially for varieties of shock treatment. However, there remains a dearth of research regarding the in vivo pharmacokinetics, mechanism of action, and toxicity of anisodamine. Consequently, this paper provides a comprehensive review of the anti-shock effects, toxicity, and pharmacokinetic characteristics of anisodamine to increase the understanding of its medicinal value, and provide reference and inspiration for the clinical application and further in-depth research of anisodamine.

Network Pharmacology Integrated Molecular Docking Reveals the Mechanism of Anisodamine Hydrobromide Injection against Novel Coronavirus Pneumonia

Background

The Coronavirus Disease 2019 (COVID-19) outbreak in Wuhan, China, was caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Anisodamine hydrobromide injection (AHI), the main ingredient of which is anisodamine, is a listed drug for improving microcirculation in China. Anisodamine can improve the condition of patients with COVID-19.

Materials and Methods

Protein-protein interactions obtained from the String databases were used to construct the protein interaction network (PIN) of AHI using Cytoscape. The crucial targets of AHI PIN were screened by calculating three topological parameters. Gene ontology and pathway enrichment analyses were performed. The intersection between the AHI component proteins and angiotensin-converting enzyme 2 (ACE2) coexpression proteins was analyzed. We further investigated our predictions of crucial targets by performing molecular docking studies with anisodamine.

Results

The PIN of AHI, including 172 nodes and 1454 interactions, was constructed. A total of 54 crucial targets were obtained based on topological feature calculations. The results of Gene Ontology showed that AHI could regulate cell death, cytokine-mediated signaling pathways, and immune system processes. KEGG disease pathways were mainly enriched in viral infections, cancer, and immune system diseases. Between AHI targets and ACE2 coexpression proteins, 26 common proteins were obtained. The results of molecular docking showed that anisodamine bound well to all the crucial targets.

Conclusion

The network pharmacological strategy integrated molecular docking to explore the mechanism of action of AHI against COVID-19. It provides protein targets associated with COVID-19 that may be further tested as therapeutic targets of anisodamine.

Possible role for anisodamine in organophosphate poisoning

In cases of organophosphate poisoning, patients are treated with a combination of antidotes. In addition to these poison-directed antidotes, patients may require extra oxygen and artificial ventilation; other modalities may also be needed due to the wide range of toxic effects. Anisodamine is a belladonna alkaloid, and like other drugs from this family is non subtype-selective muscarinic, and a nicotinic cholinoceptor antagonist, which has been employed in traditional Chinese medicine. As a muscarinic antagonist, it displays similar pharmacological effects to atropine and scopolamine. However, anisodamine is not only less potent than atropine and scopolamine but also less toxic. Current in vitro and animal model studies have demonstrated that anisodamine has protective effects in a variety of diseases. Organophosphate poisoning involves not only the central and peripheral nervous systems, but also the cardiac and respiratory systems, as well as activation of inflammatory processes and oxidative stress. Therefore, the anticholinergic and additional activities of anisodamine appear to be relevant and justify its consideration as an addition to the existing remedies. However, more research is needed, as at present data on the role of anisodamine in the management of organophosphate poisoning are limited. Here, we review the beneficial effects of anisodamine on processes relevant to organophosphate poisoning.

Developments in alternative treatments for organophosphate poisoning

Organophosphosphates (OPs) are highly effective acetylcholinesterase (AChE) inhibitors that are used worldwide as cheap, multi-purpose insecticides. OPs are also used as chemical weapons forming the active core of G-series and V-series chemical agents including tabun, sarin, soman, cyclosarin, VX, and their chemical analogs. Human exposure to any of these compounds leads to neurotoxic accumulation of the neurotransmitter acetylcholine, resulting in abnormal nerve function and multiple secondary health complications. Suicide from deliberate exposure to OPs is particularly prevalent in developing countries across the world and constitutes a major global health crisis. The prevalence and accessible nature of OP compounds within modern agricultural spheres and concern over their potential use in biochemical weapon attacks have incentivized both government agencies and medical researchers to enact stricter regulatory policies over their usage and to begin developing more proactive medical treatments in cases of OP poisoning. This review will discuss the research undertaken in recent years that has investigated new supplementary drug options for OP treatment and support therapy, including progress in the development of enzymatic prophylaxis.