Eugenol alleviates Salmonella Typhimurium-infected cecal injury by modulating cecal flora and tight junctions accompanied by suppressing inflammation

Oxyberberine alleviates lipopolysaccharide-induced intestinal barrier disruption and inflammation in human colonic Caco-2 cells in vitro

Background

Oxyberberine (OBB) is a naturally occurring isoquinoline alkaloid that is believed to possess various health-promoting properties, including anti-fungus, hepatoprotection, anti-inflammation, and anti-intestinal mucositis effects. Despite several studies reporting the health benefits of OBB in treating ulcerative colitis (UC), its specific mechanism of action has yet to be fully elucidated.

Purpose

This investigation is designed to explore the potential protective efficacy of OBB and the latent mechanism using an in vitro model of UC-like inflammatory intestinal cells.

Methods

Caco-2 cells were pretreated with OBB and subsequently exposed to lipopolysaccharide (LPS). The transepithelial electrical resistance (TEER), paracellular permeability, and the distribution and expression of tight- and adherent junction proteins were determined to assess barrier integrity. The levels of proinflammatory cytokines, reactive oxygen species (ROS), Nrf2, and NF-κB signaling cascade were analyzed via ELISA, qRT-PCR, immunofluorescence, or Western blotting.

Results

OBB was found to mitigate the effects of LPS on Caco-2 cell monolayers, as evidenced by the improvement in TEER and the decrease in FITC-dextran flux. Moreover, OBB ameliorated the LPS-induced decrease in the distribution and expression of several tight junction markers, including ZO-1, occludin, and E-cadherin. In addition, OBB treatment effectively inhibited LPS-induced increases in ROS, apoptosis, and Keap1 and decreases in Nrf2 and HO-1. LPS-induced elevations in nuclear NF-κB p65 and p-IκBα were suppressed by OBB. In addition, ML385, an antagonist of Nrf2, abolished the protective role of OBB.

Conclusion

OBB has a pronounced beneficial effect on LPS-induced damage to enteral barrier function, and the regulation of the Nrf2/NF-κB pathway is an important mechanism responsible for the protection afforded by OBB.

Anti-Inflammatory and Antioxidant Activities of Eugenol: An Update

Medicinal plants are a rich source of bioactive compounds that possess pharmacological properties for preventing and treating inflammation-related diseases. Essential oils is a chemical class that contains many bioactive compounds, such as eugenol, which is capable of inhibiting or modulating the inflammatory response. This natural product emerges as a compound that promotes various biological activities, including antioxidant activity, which makes it useful in the food industry. Recently, its pharmacological applications have also been highlighted. So, this review aims to update and discuss the most recent findings on the anti-inflammatory and antioxidant activities of eugenol, along with its mechanisms of action and therapeutic potential for treating inflammation and oxidative imbalance conditions.

Eugenol Possesses Colitis Protective Effects: Impacts on the TLR4/MyD88/NF-[Formula: see text]B Pathway, Intestinal Epithelial Barrier, and Macrophage Polarization

Eugenol (EU) has been shown to ameliorate experimental colitis due to its anti-oxidant and anti-inflammatory bioactivities. In this study, DSS-induced acute colitis was established and applied to clarify the regulation efficacy of EU on intestinal barrier impairment and macrophage polarization imbalance along with the inflammatory response. Besides, the adjusting effect of EU on macrophages was further investigated in vitro. The results confirmed that EU intervention alleviated DSS-induced colitis through methods such as restraining weight loss and colonic shortening and decreasing DAI scores. Microscopic observation manifested that EU maintained the intestinal barrier integrity in line with the mucus barrier and tight junction protection. Furthermore, EU intervention significantly suppressed the activation of TLR4/MyD88/NF-[Formula: see text]B signaling pathways and pro-inflammatory cytokines gene expressions, while enhancing the expressions of anti-inflammatory cytokines. Simultaneously, WB and FCM analyses of the CD86 and CD206 showed that EU could regulate the DSS-induced macrophage polarization imbalance. Overall, our data further elucidated the mechanism of EU's defensive effect on experimental colitis, which is relevant to the protective efficacy of intestinal barriers, inhibition of oxidative stress and excessive inflammatory response, and reprogramming of macrophage polarization. Hence, this study may facilitate a better understanding of the protective action of the EU against UC.

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

The active biological phytochemicals, crucial compounds employed in creating hundreds of medications, are derived from valuable and medicinally significant plants. These phytochemicals offer excellent protection from various illnesses, including inflammatory disorders and chronic conditions caused by oxidative stress. A phenolic monoterpenoid known as eugenol (EUG), it is typically found in the essential oils of many plant species from the Myristicaceae, Myrtaceae, Lamiaceae, and Lauraceae families. One of the main ingredients of clove oil (Syzygium aromaticum (L.), Myrtaceae), it has several applications in industry, including flavoring food, pharmaceutics, dentistry, agriculture, and cosmeceuticals. Due to its excellent potential for avoiding many chronic illnesses, it has lately attracted attention. EUG has been classified as a nonmutant, generally acknowledged as a safe (GRAS) chemical by the World Health Organization (WHO). According to the existing research, EUG possesses notable anti-inflammatory, antioxidant, analgesic, antibacterial, antispasmodic, and apoptosis-promoting properties, which have lately gained attention for its ability to control chronic inflammation, oxidative stress, and mitochondrial malfunction and dramatically impact human wellness. The purpose of this review is to evaluate the scientific evidence from the most significant research studies that have been published regarding the protective role and detoxifying effects of EUG against a wide range of toxins, including biological and chemical toxins, as well as different drugs and pesticides that produce a variety of toxicities, throughout view of the possible advantages of EUG.