Antioxidant Effects of Eugenol on Oxidative Stress Induced by Hydrogen Peroxide in Islets of Langerhans Isolated from Male Mouse

Ameliorative action of eugenol on nitrate induced reproductive toxicity in male rats

There is a great concern for studies to prevent nitrate (NO3) induced male reproductive toxicity as it might lead to infertility. Therefore, the study was aimed to investigate the ameliorative effects of eugenol on NO3 induced male reproductive toxicity in wistar rats. Adult male rats were randomly divided into five groups (n=5). The first group was served as control, the second and third group of rats were treated with 100 mg/kg bw of sodium nitrate (NaNO3) and NO3 contaminated ground water respectively. The fourth and fifth group of rats were orally intubated with eugenol (100 mg/kg bw) and then exposed to NaNO3 and NO3 contaminated ground water respectively. The treatment was continued for 52 days. Nitrate exposure significantly decreased the sperm motility, testicular 3-beta-hydroxysteroid dehydrogenase activity, serum concentration of testosterone, activities of superoxide dismutase and catalase in testis and spermatozoa and different categories of germ cells in stage VII of spermatogenesis. Further, there was significant increase in sperm abnormality and levels of nitrite (NO2) and malondialdehyde in testis and spermatozoa of NO3 treated rats. In addition, NO3 exposure distorted the histological architecture of seminiferous tubules of testis. It was established that NO3 induced high production of NO2 affected spermatogenesis, steroidogenesis and sperm motility. However, in the present study, pretreatment of eugenol prevented NO3 induced reproductive alterations by decreasing the level of NO2. These findings clearly showed the protective action of eugenol against NO3 induced oxidative stress in male reproductive system.

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.

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.

Synergistic Antigenotoxic and Antioxidant Action of Gum Arabic and Eugenol in Rat Liver Following Induction of Colorectal Carcinogenesis

OBJECTIVE

Much research has been conducted to identify natural antioxidant and antimutagenic compounds capable of preventing, reverting or treating conditions caused by oxidative stress and genotoxicity. In this study we evaluated the effects of 10% gum arabic (GA) and eugenol (EUG) on hepatic oxidative stress and genotoxicity induced by dimethylhydrazine (DMH) in rats.

METHODS

The prevention arm of the study included 4 control groups and 4 experimental groups. Once a week for 20 weeks, the controls received saline s.c. while the experimental groups received DMH at 20 mg/kg s.c. During the same period and for an additional 9 weeks, the animals received either water, 10% GA , EUG or 10% GA + EUG  by gavage. The treatment arm of the study included 4 control groups and 4 experimental groups. Once a week for 20 weeks, the controls received saline s.c. while the experimental groups received DMH at 20 mg/kg s.c. During the subsequent 9 weeks, the animals received either water, 10% GA, EUG or 10% GA + EUG  by gavage. Finally, the livers were harvested for histopathological study with HE, measurement of genotoxicity and oxidative stress.

RESULT

Genotoxicity and oxidative stress were found to be significantly lower in Group XII (animals treated concomitantly with GA and EUG). This is the first study to observe the synergistic action of GA and EUG administered concomitantly in this scenario.

CONCLUSION

Indicating a synergistic antigenotoxic and antioxidant effect on liver cells in rats with DMH-induced colorectal carcinogenesis.

The effects of eugenol on histological, enzymatic, and oxidative parameters in the major salivary glands and pancreas of healthy male Wistar rats

OBJECTIVE

We evaluated the effects of eugenol on histological, enzymatic, and oxidative parameters in the pancreas, parotid, submandibular, and sublingual glands of healthy male rats.

DESIGN

Twenty-four adult Wistar rats were assigned into four groups (n = 6/group). Control rats received 2% Tween-20 (eugenol vehicle), whereas the other animals received 10, 20, and 40 mg kg-1 eugenol through gavage daily for 60 d. Major salivary and pancreatic glands were weighed and preserved fixed for microscopic analysis and frozen for in vitro assays.

RESULTS

Eugenol did not alter glands' weight and serum amylase activity regardless of the concentration. The highest dose of eugenol caused an increase in pancreatic amylase activity and a reduction of lipase activity from serum and pancreas. Eugenol at 40 mg kg-1 diminished the activity of SOD and FRAP in the submandibular gland and CAT and FRAP in the sublingual gland. However, it did not exert any effect on GST regardless of the gland. Additionally, 40 mg kg-1 eugenol increased MDA levels in pancreatic, parotid, and submandibular glands and NO levels in the sublingual. The concentrations of eugenol induced distinct responses in the glands regarding the activity of Na+/K+, Mg2+, and total ATPase activity. They also affected histomorphometrical and histochemistrical parameters in the submandibular gland only.

CONCLUSIONS

Results indicated that 40 mg kg-1 eugenol altered most of the biochemical and oxidatived parameters of digestive glands. Only submandibular glands presented histological changes after eugenol exposure suggesting potential implications for its function.

Curcumin nanoparticles: physicochemical fabrication, characterization, antioxidant, enzyme inhibition, molecular docking and simulation studies

Curcumin is an extensively studied natural compound due to its extensive biological applications. However, there are some drawbacks linked to this compound such as poor absorption, low water-solubility, quick systemic elimination, fast metabolism, poor pharmacokinetics, low bioavailability, low penetration targeting efficacy and low stability. To overcome these drawbacks, curcumin is encapsulated in nano-carriers. In the current studies, we synthesized nanoparticles of curcumin without using nanocarriers by different methods such as nano-suspension (Cur-NSM), sonication (Cur-SM) and anti-solvent precipitation (Cur-ASP) to enhance the solubility of curcumin in water. The prepared nanoparticles were characterized by FTIR, SEM and XRD analysis. These curcumin nanoparticles were screened for their solubilities in water, DPPH scavenging, amylase, α-glucosidase and β-glucosidase enzymatic activities. The particle size of nano-curcumin was found to be in the 47.4-98.7 nm range. The reduction in particle size of curcumin dramatically increases its solubility in water to 79.2 μg mL^-1, whereas the solubility of curcumin is just 0.98 μg mL^-1. Cur-ASP showed the highest free radical scavenging potential (48.84 ± 0.98%) which was comparable with standard BHT (50.48 ± 1.11%) at 75.0 μg mL^-1. As well, Cur-ASP showed the highest inhibition of α-amylase (68.67 ± 1.02%), α-glucosidase (58.30 ± 0.52%), and β-glucosidase (64.80 ± 0.43%) at 100 μg mL^-1 which is comparable with standard drug acarbose. The greater surface area of nanoparticles exposes the various groups of curcumin for blocking the binding sites of enzymes. This strategy may be helpful in designing curcumin as a potent therapeutic agent against diabetes mellitus. Further, the molecular interactions of curcumin with α-amylase, α-glucosidase, β-glucosidase, and polyphenol oxidase were assessed by analyzing the plausible binding modes of curcumin in the binding pocket of each receptor. The best binding mode of curcumin was used to make complexes with the target proteins and their stability was confirmed by 50 ns MD simulation.

Unravelling the Therapeutic Potential of Nano-Delivered Functional Foods in Chronic Respiratory Diseases

Chronic inflammation of the respiratory tract is one of the most concerning public health issues, as it can lead to chronic respiratory diseases (CRDs), some of which are more detrimental than others. Chronic respiratory diseases include chronic obstructive pulmonary disease (COPD), asthma, lung cancer, and pulmonary fibrosis. The conventional drug therapies for the management and treatment of CRDs only address the symptoms and fail to reverse or recover the chronic-inflammation-mediated structural and functional damage of the respiratory tract. In addition, the low efficacy and adverse effects of these drugs have directed the attention of researchers towards nutraceuticals in search of potential treatment strategies that can not only ameliorate CRD symptoms but also can repair and reverse inflammatory damage. Hence, there is a growing interest toward investigating the medicinal benefits of nutraceuticals, such as rutin, curcumin, zerumbone, and others. Nutraceuticals carry many nutritional and therapeutic properties, including anti-inflammatory, antioxidant, anticancer, antidiabetic, and anti-obesity properties, and usually do not have as many adverse effects, as they are naturally sourced. Recently, the use of nanoparticles has also been increasingly studied for the nano drug delivery of these nutraceuticals. The discrete size of nanoparticles holds great potential for the level of permeability that can be achieved when transporting these nutraceutical compounds. This review is aimed to provide an understanding of the use of nutraceuticals in combination with nanoparticles against CRDs and their mechanisms involved in slowing down or reversing the progression of CRDs by inhibiting pro-inflammatory signaling pathways.

Response mechanism of gut microbiome and metabolism of European seabass (Dicentrarchus labrax) to temperature stress

In animals, the gut microbiome is vital to growth, and changes in the composition of these microbial communities may affect growth and adaptability to the environment. Temperature is another important factor that influences the healthy growth of animals. To date, the mechanism by which juvenile European seabass (Dicentrarchus labrax) and their symbiotic flora adapt to changes in environmental temperature is not well understood. Therefore, we evaluated the effect of temperature on the gut microbiota and metabolism of European seabass juveniles. We used 16S rRNA gene amplicon sequencing and non-targeted liquid chromatography with tandem mass spectrometry (LC-MS/MS)-based metabolomics to study the gut microbes of European seabass after 60 days of rearing of water temperature at 10 °C (T1), 15 °C (T2) and 20 °C (T3). At the phylum level, the abundance of the gut microbiota did not differ significantly among the three groups after 60 days of cultivation. At the genus level, however, the abundance of Faecalibacterium, Filifactor, Butyricicoccus, and Erysipelotrichaceae UCG-006 in the intestines differed significantly among the temperature groups. Compared with T2, the relative abundance of Filifactor in T1 was significantly increased, while Faecalibacterium was significantly decreased, while the relative abundance of Butyricicoccus and Erysipelotrichaceae UCG-006 in T3 was significantly increased. The LC-MS/MS analysis revealed 107 metabolites in the 10 °C group and 68 metabolites in the 20 °C group that differed significantly from those in the intestines of fish in the 15 °C control group. These metabolites are closely related to several metabolic pathways, including amino acid metabolism, glucose and lipid metabolism, and the tricarboxylic acid cycle. Correlation analysis of the Intestine microbiota, metabolic pathways, and metabolites identified metabolic pathways and metabolites that were strongly related to the observed significant differences in the microbiome among the temperature groups. These results show that temperature can induce significant changes in the gut microbiota and metabolism of European seabass juveniles, and that significant changes in metabolites may be mediated through the interaction of the microbiome and metabolic pathways.

Antidiabetic Potential of Volatile Cinnamon Oil: A Review and Exploration of Mechanisms Using In Silico Molecular Docking Simulations

Cinnamon has been used as a flavoring and medicinal agent for centuries. Much research has focused on cinnamon bark powder, which contains antioxidants, flavonoids, carotenoids, vitamins, minerals, fiber, and small amounts of essential oil. However, isolated and concentrated cinnamon essential oil may also have important medicinal qualities, particularly in antidiabetic therapy. Some of the most common essential oil constituents identified in the literature include cinnamaldehyde, eugenol, and beta-caryophyllene. Due to their high concentration in cinnamon essential oil, these constituents are hypothesized to have the most significant physiological activity. Here, we present a brief review of literature on cinnamon oil and its constituents as they relate to glucose metabolism and diabetic pathogenesis. We also present molecular docking simulations of these cinnamon essential oil constituents (cinnamaldehyde, eugenol, beta-caryophyllene) that suggest interaction with several key enzymes in glucometabolic pathways.

Eugenol Elicits Prolongevity by Increasing Resistance to Oxidative Stress in C. elegans

AIM

To analyze the efficacy of eugenol on longevity by assessing its antioxidant effect using Caenorhabditis elegans as an animal model.

BACKGROUND

Eugenol is a major polyphenolic component of Ocimum sanctum (Tulsi) which attributes wide pharmacological activities and can serve as a biomarker. However, the possible effect of eugenol on longevity in Caenorhabditis elegans has not been reported.

OBJECTIVE

The objective of this investigation was to provide first scientific based results about effect of eugenol on longevity, slowing down of paralysis in Alzheimer's model and mechanism behind it in Caenorhabditis elegans animal model system.

METHODS

The phenolic components of methanolic extract of Ocimum sanctum was analyzed by RP-HPLC. Worms were exposed to different concentrations of extract and one of its components -eugenol. Lifespan, health span, survival in CL4176 Alzheimer's model and molecular mechanism were analyzed.

RESULTS

Extract of Ocimum sanctumand eugenol increased lifespan and provided indemnity against pro-oxidants. It also significantly improved healthy ageing and slowed the progression of neurodegeneration in CL4176 Alzheimer's model of worm by increasing survival against prooxidants and slowing down the paralysis. Longevity effect was independent of the DAF-16 as observed by using DAF-16::GFP and daf-16 null mutant strains. These results implicate eugenol as a potent therapeutic compound which may curtail ageing and age related disorders like- Alzheimer's disease.

CONCLUSION

The present work demonstrated eugenol as a potential anti-ageing compound which may curtail ageing, improve heath span by enhancing resistance to oxidative stress and exerts its effect independent of DAF-16 pathway. So, it can be assumed that eugenol can be beneficial to humans as well, albeit further research is necessary before declaring it for human consumption.

Acute promyelocytic leukemia drug - arsenic trioxide in the presence of eugenol shows differential action on leukemia cells (HL-60) and cardiomyocytes (H9c2) - inference from NMR study

The increased concern of cardiovascular dysfunction by cancer therapeutics has led to more effective treatment strategies. Arsenic trioxide (As₂O₃) is a potential chemotherapeutic agent for acute promyelocytic leukemia (APL), but the effectiveness is affected by potential cardiotoxicity. Researchers have been trying to find out novel modalities to manage the adverse effects of As₂O₃. In our study, the antioxidant molecule eugenol showed protective action against the destructive impact of As₂O₃ on cardiomyocytes (H9c2) without compromising the anti-cancer property As₂O₃ on leukemia cells (HL-60). We have studied the interaction between arsenic and eugenol in physiological and acidic pH to understand the molecular mechanism of differential action of As₂O₃ in the presence of eugenol using NMR spectroscopy. The study observed that at physiological pH, arsenic and eugenol interact to form an inactive product, positively affecting H9c2 cardiomyocytes. Still, there is no such interaction in acidic pH evidenced by the useful anti-cancer property of As₂O₃. The result concludes that the antioxidant molecule eugenol is an efficient protective agent against the adverse effect of As₂O₃ on cardiomyocytes.