Cyclovirobuxine D inhibits dengue virus replication by impeding the complete autophagy in a cholesterol-dependent manner

Hedgehog pathway inhibitor HhAntag suppresses virus infection via the GLI-S1PR axis

The interplay between various signaling pathways, including tumor development, immune response, and viral infection, suggests potential mutual regulation within biological systems. To explore this, we screened 85 inhibitors targeting the Notch, Hedgehog, and Wnt signaling pathways to identify the potential antiviral candidates. Using two reporter viruses (VSV-GFP and DENV-Luc), we identified novel inhibitors with antiviral properties. Notably, the Hedgehog pathway inhibitor HhAntag exhibited broad-spectrum antiviral activity, significantly reducing the replication of viruses such as VSV, DENV, ZIKV, and SFTSV. The inhibitory effects of HhAntag were consistent with the downregulation of its target protein, GLI1; while overexpression of GLI1 promoted viral infection. HhAntag did not interfere with viral attachment, entry, or early transcription but specifically inhibited viral protein translation. Additionally, RNA-seq analysis revealed reduced expression of sphingosine-1-phosphate (S1P) signaling pathway receptors, S1PR1 and S1PR5, following HhAntag treatment. HhAntag suppresses virus infection via the GLI-S1PR axis. This study revealed the interplay between tumor-associated Hedgehog (Hh) pathway and viral infection and highlights the potential of HhAntag as a broad-spectrum antiviral drug.

Orthoflavivirus infection and the mTOR signaling pathway

Each year, mosquito-borne orthoflaviviruses, including Zika virus, dengue virus, and the Japanese encephalitis virus, threaten the health of more than 400 million people worldwide. To date, knowledge about the pathogenic mechanisms underlying orthoflavivirus infection and the interactions of these viruses with host cells is limited. Mammalian target of rapamycin (mTOR) is pivotal for cell growth and metabolism. The downstream targets of mTOR regulate protein translation and cell autophagy to affect orthoflavivirus replication, and its upstream protein AKT performs similar functions. In this work, the mechanism underlying the relationship between the mTOR signaling pathway and orthoflavivirus infection was reviewed from three perspectives: orthoflavivirus structure and life cycle, mTOR structure and signaling pathway, and regulation of the mTOR signaling pathway during orthoflavivirus infection.

The importance of paying attention to the role of lipid-lowering drugs in controlling dengue virus infection

The Flaviviridae family includes the dengue virus (DENV). About half of the world's population is in danger because of the estimated 390 million infections and 96 million symptomatic cases that occur each year. An effective treatment for dengue fever (DF) does not yet exist. Therefore, a better knowledge of how viral proteins and virus-targeted medicines may exert distinct functions depending on the exact cellular region addressed may aid in creating much-needed antiviral medications. Lipids facilitate the coordination of many viral replication phases, from entrance to dissemination. In addition, flaviviruses masterfully plan a significant rearrangement of the host cell's lipid metabolism to foster the growth of new viruses. Recent research has consistently shown the significance of certain lipid classes in flavivirus infections. For instance, in DENV-infected cells, overall cellular cholesterol (CHO) levels are only a little altered, and DENV replication is significantly reduced when CHO metabolism is inhibited. Moreover, statins significantly decrease DENV serotype 2 (DENV-2) titers, indicating that CHO is a prerequisite for the dengue viral cycle. Furthermore, many Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors are now being evaluated in human research. A new pharmacological target for the management of high CHO is PCSK9. Moreover, suppression of PCSK9 has been proposed as a possible defense against DENV. Numerous studies have generally recommended the use of lipid-lowering medications to suppress the DENV. As a result, we have investigated the DENV and popular treatment techniques in this research. We have also examined how lipid metabolism, cellular lipids, and lipid receptors affect DENV replication regulation. Lastly, we have looked at how different lipid-lowering medications affect the DENV. This article also discusses the treatment method's future based on its benefits and drawbacks.

Unlocking the Stratum Corneum Barrier to Skin Penetration for the Transdermal Delivery of Cyclovirobuxine D

Background/Objectives: Cyclovirobuxine D, a natural compound derived from the medicinal plant Buxus sinica, demonstrates a diverse array of therapeutic benefits, encompassing anti-arrhythmic properties, blood pressure regulation, neuronal protection, and anti-ischemic activity. However, its limited solubility hinders the bioavailability of current oral and injectable formulations, causing considerable adverse reactions and toxicity. Methods: In this investigation, we embarked on an unprecedented exploration of the skin penetration potential of cyclovirobuxine D utilizing chemical penetration enhancers and niosomes as innovative strategies to enhance its dermal absorption. These strategies were rigorously tested and optimized. Results: Among the tested chemical penetration enhancers, azone emerged as the most potent, achieving a 4.55-fold increase in skin penetration compared to the untreated group. Additionally, when encapsulated within niosomes, primarily composed of Span60 and cholesterol, the skin penetration of cyclovirobuxine D was notably enhanced by 1.50-fold. Furthermore, when both cyclovirobuxine D and azone were co-encapsulated within the niosomes, the skin penetration of cyclovirobuxine D was remarkably elevated by 8.10-fold compared to the solvent-dispersed group. This enhancement was corroborated through rigorous in vitro and in vivo experiments. Notably, the combination of other chemical penetration enhancers with niosome encapsulation also exhibited synergistic effects in enhancing the skin penetration of cyclovirobuxine D. Conclusions: These findings provide a compelling rationale for the administration of cyclovirobuxine D via skin-mediated transdermal delivery, offering superior safety, efficacy, and convenience. The innovative combination of niosomes and chemical penetration enhancers represents a novel system for the transdermal delivery of cyclovirobuxine D, holding immense promise for clinical applications in the treatment of brain, neuronal, and cardiovascular disorders.

Phytochemistry of Genus Buxus and Pharmacology of Cyclovirobuxine D

BACKGROUND

Genus Buxus plants, commonly known as "boxwood", are widely distributed in China. The stems, branches, and leaves of the plant are traditionally used for rheumatism, toothache, chest pain, abdominal gas, and other diseases. However, an overview of the genus Buxus remains to be provided.

PURPOSE

To provide a scientific basis for the appropriate use and further research the recent advancements in the traditional usage, phytochemistry, and, pharmacology of Buxus.

STUDY DESIGN

Chemical composition and pharmacological correlation studies through a literature review.

METHODS

Between 1970 and 2023, the available data concerning Buxus was compiled from online scientific sources, such as Sci-Finder, PubMed, CNKI, Google Scholar, and the Chinese Pharmacopoeia. Plant names were verified from "The Plant List" (http://www.theplantlist.org/).

RESULTS

To date, 266 structurally diverse chemicals have been extracted and identified from the genus Buxus. Alkaloids constitute one of its primary bioactive phytochemicals. A summary of the channels of action of Cyclovirobuxine D on the cytotoxicity of a variety of cancers has been provided.

CONCLUSION

Numerous findings from contemporary phytochemical and pharmacological studies support the traditional use, facilitating its application. Further research is necessary to address various shortcomings, including the identification of the active ingredients and quality control of the genus Buxus.

Conessine inhibits enveloped viruses replication through up-regulating cholesterol level

Dengue virus (DENV) is one of the most prevalent arthropod-borne diseases. It may cause dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS), while no effective vaccines and drugs are available. Our study demonstrated that conessine exhibits broad antiviral activity against several enveloped viruses, including DENV, vesicular stomatitis virus, and herpes simplex virus. In addition, conessine has no direct destructive effect on the integrity or infectivity of virions. Both pre-treatment and post-treatment with conessine significantly reduce DENV replication. Pre-treatment with conessine disrupts the endocytosis of enveloped viruses, while post-treatment disturbs DENV RNA replication or translation at an early stage. Through screening differentially expressed genes by transcriptome sequencing, we found that conessine may affect cholesterol biosynthesis, metabolism or homeostasis. Finally, we confirmed that conessine inhibits virus replication through up-regulating cholesterol levels. Our work suggests that conessine could be developed as a prophylactic and therapeutic treatment for infectious diseases caused by enveloped viruses.

A regenerable electrochemical sensor for electro-inactive cyclovirobuxine D detection in biological samples

Based on the pK_a determination of cyclovirobuxine D (CVB-D) using the method of potentiometry, we predicted the ionization state of CVB-D at physiological pH. Thus, by taking advantage of the ionization state and consequent non-covalent interactions between protonated CVB-D and deprotonated polymerized bromothymol blue (poly-BTB) under physiological conditions, we developed a simple and reusable electrochemical sensor that contains a poly-BTB/SWNT-modified electrode for electro-inactive CVB-D detection in biological fluids using poly-BTB as both the recognition unit and the electrochemical probe. Upon being immersed in the solution of CVB-D, the poly BTB-based electrode shows a current decrease due to the interaction-driven binding of CVB-D on the electrode surface. The current decrease in the electrochemical sensor toward CVB-D concentration shows a linear relationship in the dynamic ranges of 0.01-1 μM and 1-50 μM with a detection limit of 1.65 nM based on 3σ. The sensor can be easily regenerated through the removal of the binding of CVB-D from the electrode surface by highly negatively charged heparin, and it presents high repeatability with an RSD of less than 4.0% for seven measurements. In animal experiments, the electrochemical sensor was selective and sensitive for CVB-D determination in plasma and liver homogenates. The electrochemical sensor is readily accessible, robust, and cost-effective and holds good promise for more applications in biological and clinical fields associated with CVB-D using less technically demanding and simple operating procedures.

Cyclovirobuxine D, a cardiovascular drug from traditional Chinese medicine, alleviates inflammatory and neuropathic pain mainly via inhibition of voltage-gated Cav3.2 channels

Cyclovirobuxine D (CVB-D), the main active constituent of traditional Chinese medicine Buxus microphylla, was developed as a safe and effective cardiovascular drug in China. B. microphylla has also been used to relieve various pain symptoms for centuries. In this study, we examined and uncovered strong and persistent analgesic effects of cyclovirobuxine D against several mouse models of pain, including carrageenan- and CFA-induced inflammatory pain and paclitaxel-mediated neuropathic hypersensitivity. Cyclovirobuxine D shows comparable analgesic effects by intraplantar or intraperitoneal administration. Cyclovirobuxine D potently inhibits voltage-gated Cav2.2 and Cav3.2 channels but has negligible effects on a diverse group of nociceptive ion channels distributed in primary afferent neurons, including Nav1.7, Nav1.8, TRPV1, TPRA1, TRPM8, ASIC3, P2X2 and P2X4. Moreover, inhibition of Cav3.2, rather than Cav2.2, plays a dominant role in attenuating the excitability of isolated dorsal root ganglion neurons and pain relieving effects of cyclovirobuxine D. Our work reveals that a currently in-use cardiovascular drug has strong analgesic effects mainly via blockade of Cav3.2 and provides a compelling rationale and foundation for conducting clinical studies to repurpose cyclovirobuxine D in pain management.