Formulation optimization, anesthetic activity, skin permeation, and transportation pathway of Alpinia galanga oil SNEDDS in zebrafish (Danio rerio)

Assessment of the molecular mechanism in fish using eugenol as anesthesia based on network pharmacology

Eugenol is a commonly used fish anesthetic, but its mechanism of action is not fully understood. This study employed network pharmacology, molecular docking, and molecular dynamics simulation to explore the anesthetic targets of eugenol in fish. Initially, 63 potential targets for eugenol anesthesia were identified using databases such as SwissTarget, TargetNet, GeneCards, OMIM, and TTD. The DAVID database was utilized to analyze the GO functions and KEGG pathways of these targets, revealing 384 GO enrichment terms and 43 KEGG pathways. These terms involved neuroactive ligand-receptor interaction, calcium signaling pathway, and synaptic transmission. Subsequently, AutodockTools software facilitated molecular docking with targets in the KEGG pathway for "neuroactive ligand-receptor interaction." The results showed that eugenol had a strong affinity with these proteins. Concurrently, molecular dynamics simulations were conducted on the proteins with the top four lowest binding energies (Cnr1, Oprk1, Nr3c1, and Chrm5a) in the presence of eugenol. The eugenol-protein complexes remained stable and equilibrated within the dynamic environment. The results indicated that eugenol-anesthesia might affect membrane receptors, neurotransmitters, and ion signaling. This study elucidates the anesthetic mechanism of eugenol, enriches the primary data on fish anesthesia, and offers new analytical tools for understanding the action mechanisms of fishery drugs.

Modification of sedimentation and bioaccumulation behavior as an efficient strategy to modulate the toxicity of pyraclostrobin to zebrafish (Danio rerio)

The behavior of pesticide particles or droplets might significantly influence their environmental risks. However, studies on the risk of different pesticide formulations in aqueous environments have rarely been reported. In this study, we prepared three types of pyraclostrobin formulations to evaluate their behavior in the aqueous environment and toxicological risks to zebrafish. The results showed that pyraclostrobin emulsifiable concentrate (EC) sank faster in water with increasing hydrophilicity and density of the solvent. The particles also sank faster with increasing particle size and particle density for suspension concentrate (SC) and microcapsules (MCs). Diverse behavior in water results in different temporal and spatial distributions of the active ingredient. EC-EGDA, SC-5 μm, CS-Large and EC-MO sink or float over time, therefore reducing the effective dose suspended in water. Lower toxicological risks of the pesticides were also observed by reducing the enrichment of pyraclostrobin in zebrafish. In addition to the direct toxicity of the active ingredient, the type of pesticide formulations and their specific compositions might also influence the integrated toxicity. The environmental behavior of pesticide formulations should also be considered for their systematic assessment of environmental risks to ensure the scientific application of pesticides in different scenarios.

Journey of Alpinia galanga from kitchen spice to nutraceutical to folk medicine to nanomedicine

ETHANOPHARMACOLOGICAL IMPORTANCE

Alpinia galanga (L.) Willd (AG), belonging to Zingiberaceae family is used as a spice and condiment in various culinary preparations of Indonesia, Thailand and Malaysia. It has been also used as a key ingredient in various traditional systems of medicine for the treatment of throat infection, asthma, urinary ailments, inflammation and rheumatism amongst other conditions. AG is widely used as a functional food and included in various preparations to obtain its nutraceutical and pharmacological benefits of its phytoconstituents such as phenyl propanoids, flavonoids and terpenoids. Over the past decades, several researchers have carried out systematic investigation on various parts of AG. Numerous studies on AG rhizomes have shown positive pharmacological effects such as anti-inflammatory, anticancer, antipsoriasis, antiallergic, neuroprotective and thermogenesis. Till date, no comprehensive review summarizing the exploitation of AG into nanomedicine has been published.

AIM OF THE REVIEW

This comprehensive review aims to briefly discuss cultivation methods, propagation techniques, extraction processes for AG. The ethnopharmacological uses and pharmacological activities of AG extracts and its isolates are discussed in detail which may contribute well in further development of novel drug delivery system (NDDS) i.e. future nanomedicine.

MATERIALS AND METHODS

Information about AG was collected using search engine tools such as Google, Google Scholar, PubMed, Google Patent, Web of Science and bibliographic databases of previously published peer-reviewed review articles and research works were explored. The obtained data sets were sequentially arranged for better understanding of AG's potential.

RESULTS

More advanced genetic engineering techniques have been utilized in cultivation and propagation of AG for obtaining better yield. Extraction, isolation and characterization techniques have reported numerous phytoconstituents which are chemically phenolic compounds (phenyl propanoids, flavonoids, chalcones, lignans) and terpenes. Ethnopharmacological uses and pharmacological activity of AG are explored in numerous ailments, their mechanism of action and its further potential to explore into novel drug delivery system are also highlighted.

CONCLUSIONS

The review highlights the importance of plant tissue culture in increasing the production of AG plantlets and rhizomes. It was understood from the review that AG and its phytoconstituents possess numerous pharmacological activities and have been explored for the treatment of cancer, microbial infection, gastrointestinal disorders, neuroprotective effects, obesity and skin disorders. However, the use of AG as alternative medicine is limited owing to poor solubility of its bioactive components and their instability. To overcome these challenges, novel drug delivery systems (NDDS) have been utilized and found good success in overcoming its aforementioned challenges. Furthermore, efforts are required towards development of scalable, non-toxic and stable NDDS of AG and/or its bioactives.

The Binding of Alpinia galanga Oil and Its Nanoemulsion to Mammal GABAA Receptors Using Rat Cortical Membranes and an In Silico Modeling Platform

The anesthetic effect of Alpinia galanga oil (AGO) has been reported. However, knowledge of its pathway in mammals is limited. In the present study, the binding of AGO and its key compounds, methyl eugenol, 1,8-cineole, and 4-allylphenyl acetate, to gamma-aminobutyric acid type A (GABA_A) receptors in rat cortical membranes, was investigated using a [³H]muscimol binding assay and an in silico modeling platform. The results showed that only AGO and methyl eugenol displayed a positive modulation at the highest concentrations, whereas 1,8-cineole and 4-allylphenyl acetate were inactive. The result of AGO correlated well to the amount of methyl eugenol in AGO. Computational docking and dynamics simulations into the GABA_A receptor complex model (PDB: 6X3T) showed the stable structure of the GABA_A receptor–methyl eugenol complex with the lowest binding energy of −22.16 kcal/mol. This result shows that the anesthetic activity of AGO and methyl eugenol in mammals is associated with GABA_A receptor modulation. An oil-in-water nanoemulsion containing 20% w/w AGO (NE-AGO) was formulated. NE-AGO showed a significant increase in specific [³H]muscimol binding, to 179% of the control, with an EC₅₀ of 391 µg/mL. Intracellular studies show that normal human cells are highly tolerant to AGO and the nanoemulsion, indicating that NE-AGO may be useful for human anesthesia.

Masculinizing Effects of Chrysin-Loaded Poloxamer Micelles on Siamese Fighting Fish

Siamese fighting fish (Betta splendens) are freshwater fish that are commonly found in Thailand and other Southeast Asian countries. In the present study, chrysin-loaded polymeric micelles (CPs) were developed and investigated for the masculinizing effects, survival rate, growth indices, and toxicity on Siamese fighting fish. CPs were prepared using a poloxamer. The micelle system of CPs that were formed at a chrysin-to-polymer ratio of 1:2 was found to be the most suitable monodispersed system and exhibited a nanosized diameter (74.2 ± 1.6 nm) with a narrow size distribution (0.288 ± 0.012). In vivo studies were performed using Siamese fighting fish larvae as animal models. In the in vivo toxicity study, the fish larvae were immersed in aqueous systems containing CPs that had five different chrysin concentrations of 1, 10, 100, 1000, and 10,000 ng/mL for 24, 48, and 72 h. Blank polymeric micelles and water were used as controls. The in vivo masculinization effect of CPs with different chrysin concentrations on the fish larvae was evaluated after 5 weeks of exposure. The results demonstrated that CPs with a chrysin concentration of 1000 ng/mL showed a masculinization effect of 94.59 ± 2.76% with a high fish larvae survival rate of 72.45 ± 5.09% and low toxicity. It was concluded that the developed CPs had a significant effect on the sex reversal of Siamese fighting fish larvae with a high survival rate.