Acetylcholinesterase inhibitory activity of sesquiterpenoids isolated from Laggera pterodonta

CaMKK as a Potential Target for the Natural Product Insecticide Cytisine against Megoura japonica Matsumura

Cytisine, a botanical compound, has strong contact activity against a variety of aphids. However, the target and mechanism of its aphidicidal action remain unclear. In this study, the biochemical characteristics of cytisine against Megoura japonica were tested, and the potential target proteins of cytisine were identified, and further verified by fluorescence quenching and molecular docking. Cytisine can affect the activity of Ca2+, Mg2+-ATPase, and Na+, K+-ATPase, with inhibitory rates of 50.00% and 65.22%, respectively. Sixty-eight and fifty-one major binding proteins were identified by drug affinity responsive target stability (DARTS) and cellular thermal shift assay and mass spectrometry (MS-CETSA), respectively. 125 up-regulated and 68 down-regulated genes were obtained by transcriptome sequencing. By combining the candidate target genes of transcriptomics with the potential target proteins of DARTS and MS-CETSA, CaMKK and PPP2R3B were speculated as potential target proteins. The molecular docking results showed that the binding energies of cytisine to CaMKK and PPP2R3B were -6.61 kcal/mol and -6.53 kcal/mol. The fluorescence intensity of CaMKK protein decreased by 28.50, 34.86, 39.68, 51.00, 55.16, 73.99, and 83.29% after different concentrations of cytisine treatment. This research proved that CaMKK is the potential target of cytisine, providing a new target resource for the creation of new pesticides.

Larvicidal activity of terpenes and their derivatives against Aedes aegypti: a systematic review and meta-analysis

Aedes aegypti (Diptera: Culicidae) is the primary arthropod vector responsible for the transmission of dengue, which is present in more than one hundred countries. The application of synthetic larvicides is one of the most common strategies used for dengue control, but their prolonged use can cause larvicide resistance or tolerance, environmental damage, and have toxic effects on human and animal health. Thus, faced with this problem, there have been increasing efforts to find alternative larvicides against Ae. Aegypti. This search has been mainly focused on naturally occurring chemical compounds, driven by the evidence of their potential effectiveness, and by a desire to find more sustainable, environmentally friendly, and safe alternatives to synthetic larvicides. Thus, the present study aimed to review the effects of terpenes and their derivatives on mortality of the Ae. aegypti larvae, focusing mainly on a lethal concentration of 50% (LC50), in addition to summarizing information on its mechanisms of action and effects on non-target organisms. We searched the main databases for studies published up to April 2024 using relevant keywords, and data were extracted and analyzed qualitatively and quantitatively. Twenty-one articles describing 69 different terpenes and derivatives met the criteria of the review and meta-analysis. Among them, 76.8% were terpenoids and 23.2% terpenes. The LC50 ranged from 0.4 to 1628.2 ppm. The present review and meta-analysis showed that the terpenes and terpenoids can be promising chemical templates for use in eco-friendly larvicides against Ae. aegypti.

Investigating the effects of Laggera pterodonta on H3N2-Induced inflammatory and immune responses through network pharmacology, molecular docking, and experimental validation in a mice model

For centuries, Laggera pterodonta (LP), a Chinese herbal medicine, has been widely employed for treating respiratory infectious diseases; however, the mechanism underlying LP's effectiveness against the influenza A/Aichi/2/1968 virus (H3N2) remains elusive. This study aims to shed light on the mechanism by which LP combats influenza in H3N2-infected mice. First, we conducted quasi-targeted metabolomics analysis using liquid chromatography-mass spectrometry to identify LP components. Subsequently, network pharmacology, molecular docking, and simulation were conducted to screen candidate targets associated with AKT and NF-κB. In addition, we conducted a series of experiments including qPCR, hematoxylin-eosin staining, flow cytometry, immunohistochemistry, and enzyme-linked immunosorbent assay to provide evidence that LP treatment in H3N2-infected mice can reduce pro-inflammatory cytokine levels (TNF-α, IL-6, IL-1β, and MCP-1) while increasing T cells (CD3+, CD4+, and CD8+) and syndecan-1 and secretory IgA expression. This, in turn, aids in the prevention of excessive inflammation and the fortification of immunity, both of which are compromised by H3N2. Finally, we utilized a Western blot assay to confirm that LP indeed inhibits the AKT/NF-κB signaling cascade. Thus, the efficacy of LP serves as a cornerstone in establishing a theoretical foundation for influenza treatment.