Pharmacodynamic, pharmacokinetic, toxicity, and recent advances in Eugenol's potential benefits against natural and chemical noxious agents: A mechanistic review

Eugenol Nanoparticles in Dental Composites: Literature Review of Antimicrobial, Anti-Inflammatory, and Clinical Applications

The formation of microbial colonies and biofilms are common on dental restorations. This can lead to secondary caries. Another common complication is the post-operative inflammation noted in patients. The traditionally used dental composites are designed without the inherent components having antimicrobial and inflammatory properties. This has become a major challenge in current restorative dentistry applications. In order to address these challenges, a possible approach is to incorporate eugenol nanoparticles (NPs) into dental composites. This approach can offer dual therapeutic benefits since eugenol possess both antimicrobial and inflammatory properties. In fact, compared to synthetic antimicrobial agents, eugenol exhibits antibacterial activity not only against Streptococcus mutans but also against a range of oral pathogens. It also exhibits anti-inflammatory effects that can promote healing by reducing post-operative sensitivity. In spite of the above benefits, eugenol cannot be incorporated directly into dental materials. This is because eugenol is highly volatile and has poor water solubility. The encapsulation of eugenol in suitable nano-materials can overcome these limitations. In addition, it can enable the controlled and sustained release of desirable agents for long-term therapeutic action. In this review, we explore the mechanisms, advantages and potential clinical applications of dental composites containing NP integrated with eugenol. We highlight the advantages of having antimicrobial and anti-inflammatory functions in a single restorative material. At the same time, we acknowledge the need for more in-depth research to optimize NP formulations with eugenol that does not compromise the mechanical properties of dental materials. Based on a thorough literature review, we believe that this approach has much potential in restorative dentistry procedures that will aid therapeutic outcomes in the future.

Cisplatin-eugenol Pt(IV) prodrugs target colon cancer stem cells: A novel strategy for enhanced anticancer efficacy

Platinum(IV) compounds possess distinct properties that set them apart from platinum(II) compounds. Often designed as prodrugs, they are reduced within cancer cells to their active platinum(II) form, enabling their cytotoxic effects. Their versatility also lies in their ability to be functionalized and conjugated with bioactive molecules to enhance cancer cell targeting. This report introduces new prodrugs that combine antitumor cisplatin with axially coordinated eugenol, leveraging their synergistic action to target cancer stem cells. A third bioactive ligand, 4-phenylbutyrate or octanoate, was added to further enhance biological activity, creating 'triple action' prodrugs. These new platinum(IV) prodrugs offer a novel approach to cancer therapy by improving targeting, increasing efficacy, overcoming drug resistance, and reducing tumor invasiveness while sparing healthy tissue.

Eugenol-Loaded Lipid Nanoparticles-Derived Hydrogels Ameliorate Psoriasis-like Skin Lesions by Lowering Oxidative Stress and Modulating Inflammation

Psoriasis is a chronic T-cell-mediated autoimmune skin disorder characterized by excessive epidermal thickening, overproliferation of keratinocyte, disruption of epidermal cell differentiation, and increased blood vessel growth in the dermal layer. Despite the common use of corticosteroids in psoriasis treatment, their limited efficacy and numerous side effects pose significant challenges. This research introduces a promising alternative approach by encapsulating eugenol (EU) in soya phosphatidylcholine (SPC) nanoparticles (EUNPs) which showed spherical shape nanoparticles with a hydrodynamic size of approximately 200 nm, polydispersity index 0.23, encapsulation efficiency of 85% having good colloidal stability indicated by ζ-potential of -27 mV. Later on, these EUNPs were formulated into a topical hydrogel system by using Carbopol 974P (EUNPGel), which exhibited superior drug loading, enhanced release kinetics for 48 h, long-term stability, and the ability to scavenge reactive oxygen species (ROS). Furthermore, EUNPs inhibited keratinocyte proliferation, induced apoptosis, and augmented the uptake of IL-6-mediated inflammation in human keratinocyte cells. Application of EUNPs-loaded gels (EUNPGel) to imiquimod-induced psoriatic lesions demonstrated effective dermal penetration, suppressed keratinocyte hyperplasia and restored epidermal growth. This led to a remarkable reduction in the Psoriasis Area and Severity Index (PASI) score from 3.75 to 0.5 within 5 days. This novel approach enhances ROS scavenging capacity, improves cellular uptake, facilitates skin penetration and retention, reduces the activity of hyperactive immune cells, and suggests potential applications for treating other immune-related disorders such as acne and atopic dermatitis.

In vitro antiviral activity of eugenol on Singapore grouper iridovirus

The high mortality rate of Singapore grouper iridovirus (SGIV) posing a serious threat to the grouper aquaculture industry and causing significant economic losses. Therefore, finding effective drugs against SGIV is of great significance. Eugenol (C10H12O2) is a phenolic aromatic compound, has been widely studied for its anti-inflammatory, antioxidant and antiviral capacity. In this study, we explored the effect of eugenol on SGIV infection and its possible mechanisms using grouper spleen cells (GS) as an in vitro model. We found that treatment of GS cells with 100 μM eugenol for 4 h exhibited the optimal inhibitory effect on SGIV. Eugenol was able to reduce the expression level of inflammatory factors by inhibiting the activation of MAPK pathway and also inhibited the activity of NF-κB and AP-1 promoter. On the other hand, eugenol attenuated cellular oxidative stress by reducing intracellular ROS and promoted the expression of interferon-related genes. Therefore, we conclude that eugenol inhibits SGIV infection by enhancing cellular immunity through its anti-inflammatory and antioxidant functions.

Eugenol and lidocaine inhibit voltage-gated Na+ channels from dorsal root ganglion neurons with different mechanisms

Eugenol (EUG) is a bioactive monoterpenoid used as an analgesic, preservative, and flavoring agent. Our new data show EUG as a voltage-gated Na+ channel (VGSC) inhibitor, comparable but not identical to lidocaine (LID). EUG inhibits both total and only TTX-R voltage-activated Na+ currents (INa) recorded from VGSCs naturally expressed on dorsal root ganglion sensory neurons in rats. Inhibition is quick, fully reversible, and dose-dependent. Our biophysical and pharmacological analyses showed that EUG and LID inhibit VGSCs with different mechanisms. EUG inhibits VGSCs with a dose-response relationship characterized by a Hill coefficient of 2, while this parameter for the inhibition by LID is 1. Furthermore, in a different way from LID, EUG modified the voltage dependence of both the VGSC activation and inactivation processes and the recovery from fast inactivated states and the entry to slow inactivated states. In addition, we suggest that EUG, but not LID, interacts with VGSC pre-open-closed states, according to our data.