Computer-aided molecular and biological-immune modeling of illicium verum bioactive compounds employing the Egyptian Nile snail Biomphalaria alexandrina as a paradigm

Abstract

In pursuit of sustainable biocontrol strategies, this study explores Illicium verum (star anise) as a dual-action anti-inflammatory/oxidative and molluscicidal agent using Biomphalaria alexandrina, the intermediate host of Schistosoma mansoni, as an eco-relevant in vivo model. Two experimental snail groups were employed: a control group and a treatment group exposed to a sublethal concentration of I. verum extract (LC₁₀ = 315 ppm). Through a combined pipeline of phytochemical profiling, computational simulations, and in vivo assays, we identified flavonoids and phenylpropanoids with potent bioactivity. Molecular docking and ADMET screening highlighted kaempferol, quercetin, and rutin as top ligands, which bind effectively to key snail proteins such as cytochrome c oxidase and actin. In vivo analyses confirmed immunomodulatory effects, and these findings were validated through oxidative/inflammatory biomarker assays, which revealed altered cytokine levels (IFN-γ, IL-2 and IL-6), tissue remodeling, and reduced oxidative stress. Histopathological and immunohistochemical evaluations revealed significant tissue alterations in the digestive gland and head-foot regions of treated snails. Gene and protein interaction networks supported these findings by linking compound action to immune and oxidative regulatory pathways. This integrative study demonstrated that Illicium verum contains bioactive compounds capable of modulating oxidative stress, immune responses, and tissue integrity in B. alexandrina as an animal model. Integrating phytochemical analysis with in silico and molecular simulations offers a powerful approach for understanding and optimizing bioactive compounds. While phytochemical profiling identifies key constituents such as flavonoids and phenylpropanoids, computational tools predict their binding to biological targets, pharmacokinetics, and safety. This combination not only streamlines the discovery of effective and low-toxicity compounds but also clarifies their mechanisms of action at the molecular level, enhancing both the precision and efficiency of experimental validation. These results position star anise as a promising, eco-friendly candidate for the development of novel molluscicidal and anti-inflammatory agents supporting sustainable disease control strategies.

Keywords: Biomphalaria alexandrina model; Illicium verum (star anise); Biological activities; Computer-aided molecular simulation; Gene‒protein interaction; Oxidative–immune mediators.

Fig. 1

Phytochemicals compounds found in Illicium verum extract

Fig. 2

Visually representative bubble chart of B. alexandrina proteins and their associated functions. The size of each bubble indicates the length of the function description

Fig. 3

Molecular docking and binding affinity visualization of star anise ligands with B. alexandrina proteins. BA, Vina score (binding affinity in kcal/mol); (Å3), cavity volume

Fig. 3

Molecular docking and binding affinity visualization of star anise ligands with B. alexandrina proteins. BA, Vina score (binding affinity in kcal/mol); (Å3), cavity volume

Fig. 4

I. In silico simulation of oxidative and inflammatory protein/gene interactions. A: Concentric layout network visualization of the inflammatory and oxidative biomarkers. Data obtained from PICKLE (with 30 edges and 58 nodes, PPI quality 15), the cross-checking (default) filtering method, normalization level protein (UniProt), first neighbors and any interactions between them network setup). (Accessed on 3 March 2024). B-D: Top 15 interacting genes of IFN-γ, IL-2, and IL-6. The data were retrieved from the UCSC Genome Browser Gene Interaction Graph, highlighting the Drug Bank interactions obtained through gene interactions and pathways. Accessed on 18 May 2024. The interactions are colored by support. Genes with black colored: treatment hits by Drug Bank; gray: interactions from several datasets with only text mining; light blue: interaction database; blue: pathway database. ROMO1: reactive oxygen species modulator; IFNG: interferon gamma; IL-2: interleukin-2; IL-6: interleukin-6. II: Effects of Illicium verum on oxidative/inflammatory biomarkers in control and exposed snails. E: Anti-inflammatory capacity (pg/ml) of snail hemolymph. F: antioxidant capacity nmol/g of snail tissue homogenate. The values are presented as mean ± standard deviation (SD) after 3- and 7-day time intervals; n = 10 snails. IFN-γ interferon gamma, IL-2 interleukin-2, TAC total antioxidant capacity, MDA malondialdehyde. *p ≤ 0.05 vs control group

Fig. 5

Hemocyte morphology and immunohistochemical/histological investigation of the impact of illicium verum on B. alexandrina snails (head foot and digestive gland). A: Photomicrographs showing snail hemocytes (× 40) of normal control and after exposure to star anise. S, round small hemocyte; H, hyalinocyte; G, granulocyte; N, nucleus; V, vacuoles; P, pseudododia. B: Immunohistochemical changes in IL-6 expression (light blue arrow); normal distribution within the control group and lower expression B. alexandrina snail treated with I. verum. C: Histological changes; control group, normal head foot of B. alexandrina snail with connective tissue (CT), muscle layer (ML), mucous cell (MC), and columnar epithelia (CE). Head-foot of B. alexandrina snails treated with I. verum with muscle fiber degeneration and the presence of empty spaces or vacuoles within the muscle tissue (V) and connective tissues with edema and densely stained in outer layer (TE). Normal digestive gland of the control group contained lumen (L), excretory cell (EC), digestive cell (DC), and connective tissue among hepatopancreatic tubules (CT). The digestive glands of B. alexandrina snails treated with a sublethal dose of I. verum caused necrotic changes in excretory cells (EC) and digestive cells (DC), dilation of the lumen, fusion of more than two tubules into a larger lumen (L), connective tissue among tubules (CT) and cellular vacuoles (V) were observed