Cardiovascular Activity of the Chemical Constituents of Essential Oils

Citronellal: a natural aldehyde with important properties

Among the several terpenes existing in nature, Citronellal, a monoterpene aldehyde, deserves to be highlighted for its biological properties that have been pointed out in numerous studies. This work aimed to conduct a literature review on its biological properties. Citronellal is a prominent compound in the essential oils of Cymbopogon genus plants. Apart from being employed as a fragrance ingredient in aromas, fragrances, and cosmetics, it is also used as an intermediate in synthesising (-)-menthol. Various studies have demonstrated Citronellal's potential as an antibacterial compound, particularly anti-Staphylococcus and Escherichia bacteria. Citronellal also has antifungal properties against several fungi, especially fungi of the genus Candida. The studies found showed that Citronellal also has insecticidal, acaricidal, antiparasitic, anaesthetic, antiviral, antioxidant, antinociceptive, cardioprotective, antihypertensive, anti-inflammatory, antidiabetic, and anticancer properties.

Investigation of the Molecular Mechanisms Underlying the Therapeutic Effect of Perilla frutescens L. Essential Oil on Acute Lung Injury Using Gas Chromatography-Mass Spectrometry and Network Pharmacology

OBJECTIVE

The present study aimed to investigate the molecular mechanism through which Perilla essential oil treats acute lung injury (ALI) through network pharmacology, molecular docking, and in vitro assays.

METHODS

Relevant ALI targets of the active ingredients of Perilla essential oil were predicted using the SwissTargetPrediction database and meta TarFisher database. These ALI targets were then screened using GeneCards and DisGeNET, and differentially expressed ALI target genes were identified using the Gene Expression Omnibus (GEO) database. Next, key targets were enriched using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). Protein-protein interaction network analysis was performed to obtain targets with the highest degree values for molecular docking with Perilla essential oil active ingredients. For in vitro experiments, lipopolysaccharide (LPS) was used to induce an ALI inflammation model using RAW264.7 cells. The model cells were then treated with Perilla essential oil to detect the protein expression levels of vascular endothelial factor (NO), tumor necrosis factor (TNF-α), and p65 nuclear transcription factor in them.

RESULTS

Sixty-eight key targets of Perilla oil were identified for the treatment of ALI. These targets were found to be involved in biological processes related to peptides, response to lipopolysaccharides, the positive regulation of cytokine production, etc., using GO. The signaling pathways found to be associated with the targets included the AGE-RAGE signaling pathway in diabetic complications, the NF-kappa B signaling pathway, and small cell lung cancer and other inflammatory signaling pathways. The five key targets that showed good binding activity with Perilla oil active ingredients included TNF, RELA, PARP1, PTGS2, and IRAK4. In vitro assays showed that Perilla essential oil could significantly reduce NO and TNF-α levels and inhibit the phosphorylation of nuclear transcription factor P65, thus inhibiting the activation of NF-κB signaling pathway. Conclusion Perilla essential oil can play a role in the treatment of ALI by inhibiting the activation of the NF-κB signaling pathway and preventing an excessive inflammatory response. This study thus provides a reference for the in-depth study of the mechanisms through which Perilla essential oil treats ALI.

The Beneficial Effect of Carvacrol in HL-1 Cardiomyocytes Treated with LPS-G: Anti-Inflammatory Pathway Investigations

Carvacrol (CAR), a natural phenolic monoterpene, possesses different biological activities, such as anti-inflammatory and antioxidant activities. The current study aimed to evaluate the response of HL-1 cardiomyocytes to an inflammatory stimulus triggered by lipopolysaccharide from Porphyromonas gingivalis (LPS-G), alone or in co-treatment with CAR, to investigate the potential protective role of CAR in the inflammatory process through modulation of the TLR4/NFκB/NALP3/IL-1β pathway and ROS production. In an in vitro experiment, HL-1 cardiomyocytes were exposed to LPS-G and incubated with CAR. We evaluated the anti-inflammatory effect of CAR by the reduction in TLR4, NFκB, NALP3, and IL-1β expression using immunofluorescence staining. Western blot analysis also validated the modulation of the TLR4/NFκB/NALP3/IL-1β pathway. ROS analyses confirmed the protective effects of CAR. Our results suggest that CAR could provide a significant protection role against inflammatory stimulus generated by LPS-G, involving the suppression of the TLR4/NFκB/NALP3/IL-1β signaling pathway.

Cold-pressed oil from Citrus aurantifolia inhibits the proliferation of vascular smooth muscle cells via regulation of PI3K/MAPK signaling pathways

Vascular occlusive disease is a chronic disease with significant morbidity and mortality. Although a variety of therapies and medications have been developed, the likelihood of disease re-emergence is high and this can be life-threatening. Based on a previous screening experiment related to vascular obstructive diseases using 34 types of essential oils, cold-pressed oil (CpO) from Citrus aurantifolia (lime) has been demonstrated to have the best effect for the inhibition of vascular smooth muscle cells (VSMCs) proliferation. The aim of the present study was to evaluate the effect of lime CpO on the pathological changes of VSMCs. To determine this, the effect of lime CpO on VSMC proliferation, a major cause of vascular disease, was investigated. To determine the safe concentration interval for toxicity of CpO during VSMC culture, a dilution of 1x10^-5 was determined using Cell Counting Kit-8 assay, which was confirmed to be non-toxic using a lactate dehydrogenase assay. To examine the effect of lime CpO in cellular signaling pathways, changes in phosphorylation of both the PI3K/AKT/mTOR and extracellular signal-regulated MEK/ERK signaling pathways with serum were investigated. Furthermore, lime CpO with FBS also significantly decreased the expression levels of the cell cycle regulators cyclin D1 and proliferating cell nuclear antigen. Additionally, lime CpO with FBS significantly inhibited the sprouting of VSMCs in an ex vivo culture system. These results suggested that lime CpO inhibited the abnormal proliferation of VSMCs and can be developed as a nature-based therapeutic agent for obstructive vascular disease.

Nanoencapsulation of thyme essential oil: a new avenue to enhance its protective role against oxidative stress and cytotoxicity of zinc oxide nanoparticles in rats

Although the green synthesis of nanometals is eco-friendly, the toxicity or safety of these biosynthesized nanoparticles in living organisms is not fully studied. This study aimed to evaluate the potential protective role of encapsulated thyme oil (ETO) against zinc oxide nanoparticles (ZnO-NPs). ETO was prepared using a mixture of whey protein isolate, maltodextrin, and gum Arabic, and ZnO-NPs were synthesized using parsley extract. Six groups of male Sprague-Dawley rats were treated orally for 21 days which included the control group, ZnO-NP-treated group (25 mg/kg body weight (b.w.)), ETO-treated groups at low or high dose (50, 100 mg/kg b.w.), and the groups that received ZnO-NPs plus ETO at the two tested doses. Blood and tissue samples were collected for different assays. The results showed that carvacrol and thymol were the major components in ETO among 13 compounds isolated by GC-MS. ZnO-NPs were nearly spherical and ETOs were round in shape with an average size of 38 and 311.8 nm, respectively. Administration of ZnO-NPs induced oxidative stress, DNA damage, biochemical, ctyogentical, and histological changes in rats. ETO at the tested doses alleviated these disturbances and showed protective effects against the hazards of ZnO-NPs. It could be concluded that encapsulation of thyme oil using whey protein isolate, maltodextrin, and gum Arabic improved the antioxidant properties of ETO, probably possess synergistic effects, and can be used as a promising tool in pharmaceutical and food applications.

Anti-atherosclerotic Effects of Spice-Derived Phytochemicals

Cardiovascular diseases are the leading cause of death in the world. Atherosclerosis is characterized by oxidized lipid deposition and inflammation in the arterial wall and represents a significant problem in public health and medicine. Some dietary spices have been widely used in many countries; however, the mechanism of their action as it relates to the prevention and treatment of atherosclerosis is still poorly understood. In this review, we focus on the properties of various spice-derived active ingredients used in the prevention and treatment of atherosclerosis, as well as associated atherosclerotic risk factors. We provide a summary of the mechanisms of action, epidemiological analyses, and studies of various components of spice used in the clinic, animal models, and cell lines related to atherosclerosis. Most notably, we focused on mechanisms of action by which these spice-derived compounds elicit their lipid-lowering, anti-inflammatory, antioxidant, and immunomodulatory properties, as well as their involvement in selected biochemical and signal transduction pathways. It is suggested that future research should aim to design well-controlled clinical trials and more thoroughly investigate the role of spices and their active components in the prevention/treatment of atherosclerosis. Based on this literature review, it appears that spices and their active components are well tolerated and have few adverse side effects and, therefore, provide a promising adjunctive treatment strategy for patients with atherosclerosis.

Cardiovascular effects of farnesol and its β-cyclodextrin complex in normotensive and hypertensive rats

Farnesol (FAR) is a sesquiterpene alcohol with a range of reported biological effects including cardioprotective, antioxidant and antiarrhythmic properties. However, due to its volatility, the use of drug incorporation systems, such as cyclodextrins, have been proposed to improve its pharmacological properties. Thus, the aim of this study was to evaluate and characterize the cardiovascular effects of FAR alone, and to investigate the antihypertensive effects of FAR complexed with β-cyclodextrin (βCD) in rats. Mean arterial pressure (MAP) and heart rate (HR) were measured before and after intravenous administration of FAR (0,5; 2,5; 5 and 7,5 mg/kg) in normotensive rats, and after oral acute administration (200 mg/kg) of FAR and FAR/βCD complex in NG-nitro-L-arginine-methyl-ester (L-NAME) hypertensive rats. In normotensive animals, FAR induced dose-dependent hypotension associated with bradycardia. These effects were not affected by pre-treatment with L-NAME or indomethacin (INDO), but were partially attenuated by atropine. Pre-treatment with hexamethonium (HEXA) only affected hypotension. In the hypertensive rats, FAR/βCD potentialized the antihypertensive effect when compared to FAR alone. Molecular docking experiments demonstrated for the first time that FAR has affinity to bind to the M₃ and M₂ muscarinic, and nicotinic receptors through hydrogen bonds in the same residues as known ligands. In conclusion, our results demonstrated that FAR induced hypotension associated with bradycardia, possibly through the muscarinic and nicotinic receptors. The inclusion complex with βCD improved the antihypertensive effects of FAR, which can be relevant to improve current cardiovascular therapy using volatile natural components.

Transcriptome sequencing reveals genes involved in cadmium-triggered oxidative stress in the chicken heart

As a ubiquitous heavy metal, cadmium (Cd) is highly toxic to various organs. However, the effects and molecular mechanism of Cd toxicity in the chicken heart remain largely unknown. The goal of our study was to investigate the cardiac injury in chickens' exposure to Cd. We detected the levels of oxidative stress-related molecules in the Cd-induced chicken heart, and assessed the histopathological changes by hematoxylin and eosin staining. RNA sequencing was performed to identify differentially expressed mRNAs between the Cd-induced group and control group. The expression of candidate genes involved in oxidative stress was certified by quantitative reverse transcription PCR. Our results showed that the expression of glutathione, peroxidase, and superoxide dismutase was significantly decreased and malondialdehyde was increased in the heart of chickens by Cd induction. The disorderly arranged cardiomyocytes, swelled and enlarged cells, partial cardiomyocyte necrosis, blurred morphological structure, and notable inflammatory cell infiltration were observed in the Cd-induced chicken heart. RNA sequencing identified 23 upregulated and 11 downregulated mRNAs in the heart tissues of the chicken in the Cd-induced group, and functional pathways indicated that they were associated with oxidative stress. Moreover, CREM, DUSP8, and ITGA11 expressions were significantly reduced, whereas LAMA1 expression was induced in heart tissue of chickens by Cd treatment. Overall, our findings revealed that oxidative stress and pathological changes in the chicken heart could be triggered by Cd. The mRNA transcriptional profiles identified differentially expressed genes in the chicken heart by Cd induction, revealing oxidative stress-related key genes and enhancing our understanding of Cd toxicity in the chicken heart.

In vitro effects of citral on the human myometrium: Potential adjunct therapy to prevent preterm births

BACKGROUND

Premature infants contribute to infant morbidity and mortality especially in low resource settings. Information on tocolytic and/or anti-inflammatory effects of several plant extracts, such as citral, could help prevent preterm birth cases and reduce the number of preterm infants. The aim of this study was to evaluate the in vitro tocolytic and anti-inflammatory effect of citral on myometrial tissues of the human uterus.

METHODS

Myometrial samples from uteri obtained after hysterectomy were used in functional tests to evaluate the inhibitory effect of citral on PGF-2α induced contractions. The intracellular cyclic adenosine monophosphate (cAMP) levels generated in response to citral in human myometrial homogenates were measured by ELISAs. Forskolin was used as a positive control. The anti-inflammatory effect of citral was determined through the measurement of two pro-inflammatory cytokines, tumor necrosis factor-α (TNFα) and interleukin (IL)-1β, and the anti-inflammatory cytokine IL-10, in human myometrial explants stimulated with lipopolysaccharide (LPS).

RESULTS

Citral was able to induce a significant inhibition of PGF-2α induced contractions at the highest concentration level (p < .05). Citral caused a concentration-dependent increase in myometrial cAMP levels (p < .05) and a concentration-dependent decrease in LPS-induced TNFα and IL-1β production, while IL-10 production increased significantly (p < .05). The anti-inflammatory and tocolytic effects induced by citral could be associated with an increase in cAMP levels in human myometrial samples.

CONCLUSION

These properties place citral as a potentially safe and effective adjuvant agent in preterm birth cases, an obstetric and gynecological problem that requires urgent attention.

Estragole prevents gastric ulcers via cytoprotective, antioxidant and immunoregulatory mechanisms in animal models

BACKGROUND

Estragole is an aromatic organic compound belonging to the class of phenylpropanoids derived from cinnamic aldehydes and present in essential oils of plant species, such asRavensara anisata (madeira), Ocimum basilicum (manjericão/alfavaca) and Croton zehntneri (canelinha). Pharmacological studies report its anti-inflammatory, antioxidant and vasorelaxant activity.

HYPOTHESIS/PURPOSE

This study aimed to evaluate the acute non-clinical toxicity, gastroprotective activity and the related mechanisms of action.

METHODS

Acute toxicity was assessed according to OECD guide 423 in mice. Ethanol, stress, piroxicam and pylorus ligation-induced gastric ulcer models were used to investigate antiulcer properties. The related mechanisms of action were using the ethanol-gastric lesions protocol.

RESULTS

In the acute oral toxicity assay, doses of 300 or 2000 mg/kg of estragole administered orally in Swiss mice did not induce any behavioral changes. However, the dose of 2000 mg/kg showed a decrease in water and feed intake. Lethal dose 50 % (LD50) was set to be equal to or greater than 2500 mg/kg, according to OECD. In all evaluated protocols, estragole (31.25, 62.5, 125 and 250 mg/kg) significantly reduced the area of ​​ulcerative lesion when compared to control groups. To investigate the mechanisms involved in the gastroprotective activity, the antisecretory or neutralizing of gastric secretion, cytoprotectant, antioxidant and immunoregulatory effects were evaluated. Results showed that treatment with estragole (250 mg/kg) reduced (p < 0.05) the volume of the gastric juice. Besides, sulfhydryl groups, nitric oxide, mucus and prostaglandins seems to be involved in the gastroprotective property. Treatment also increased (p < 0.001) levels of reduced glutathione (GSH), interleukin-10 (IL-10) and positive cells marked for glutathione peroxidase (GPx) and cyclooxygenase 2 (COX-2). It also reduced (p < 0.001) malondialdehyde (MDA), myeloperoxidase (MPO), interleukin-1 beta (IL-1β), tumor necrosis factor-alpha (TNF-α) and inducible nitric oxide synthase (iNOS) (p < 0.05) levels.

CONCLUSION

Thus, it is possible to infer that estragole presents gastroprotective activity related to antisecretory, cytoprotective, antioxidant and immunomodulatory mechanisms.

Bradycardic and Antiarrhythmic Effects of the D-Limonene in Rats

Background

D-limonene (DL) is a monoterpene and is the major component in the essential oil of citrus fruit. It presents antihyperglycemic and vasodilatation activities.

Objectives

This study evaluated the cardiovascular effects and potential antiarrhythmic of DL in rats.

Methods

Hemodynamic and electrocardiographic (ECG) parameters were measured in male Wistar rats, which under anesthesia had been cannulated in the abdominal aorta and lower vena cava and had electrodes subcutaneously implanted. In the in vitro approach, the heart was removed and perfused using the Langendorff technique. The significance level adopted was 5% (p < 0.05).

Results

DL, in doses of 10, 20, and 40 mg/kg (i.v), produced intense and persistent bradycardia associated with hypotension. Bradycardia with prolonged QTc was observed in the ECG in vivo recording. In the in vivo model of arrhythmia induced by Bay K8644, DL (10 mg/kg) decreased the arrhythmia score from 15.33 ± 3.52 to 4.0 ± 2.64 u.a (p < 0.05, n = 4). In isolated perfused hearts, DL (10^-3 M) promoted significant reductions in heart rate (from 228.6 ± 8.5 ms to 196.0 ± 9.3 bpm; p < 0.05) and left ventricular development pressure (from 25.2 ± 3.4 to 5.9 ± 1.8 mmHg; n = 5, p < 0.05).

Conclusions

DL produces bradycardia and antiarrhythmic activity in rat heart.

Biological Activities of Essential Oils from Leaves of Paramignya trimera (Oliv.) Guillaum and Limnocitrus littoralis (Miq.) Swingle

The present study aimed to determine the bioactivities of essential oils extracted from the leaves of Paramignya trimera and Limnocitrus littoralis, including cytotoxicity, antiviral, antibacterial, antimycotic, and antitrichomonas effects. Herein, it was indicated that P. trimera and L. littoralis oils showed no cytotoxicity on normal cells, namely MT-4, BHK-21, MDBK, and Vero-76. P. trimera oil (i) exhibited the strongest inhibition against Staphylococcus aureus with MIC and MLC values of 2% (v/v); (ii) showed MIC and MLC values of 8% (v/v) in Candida parapsilosis; and (iii) in the remaining strains, showed MIC and MLC values greater than or equal to 16% (v/v). On the other hand, L. littoralis oil (i) displayed the strongest inhibition against Candida tropicalis and Candida parapsilosis with 2% (v/v) of MIC and MLC; and (ii) in the remaining strains, possessed MIC and MLC greater than or equal to 16% (v/v). In addition, antitrichomonas activities of the oils were undertaken, showing IC₅₀, IC₉₀, MLC values, respectively, at 0.016%, 0.03%, and 0.06% (v/v) from P. trimera, and 0.03%, 0.06%, 0.12% (v/v) from L. littoralis, after 48 h of incubation. The oils were completely ineffective against ssRNA+ (HIV-1, YFV, BVDV, Sb-1, CV-B4), ssRNA- (RSV, VSV), dsRNA (Reo-1), and dsDNA (HSV-1, VV) viruses. This is the first report describing the cytotoxicity, antiviral, antibacterial, antimycotic, and antitrichomonas activities of the essential oils of P. trimera and L. littoralis.

In vitro Antimicrobial Activity of Essential Oil Extracted from Leaves of Leoheo domatiophorus Chaowasku, D.T. Ngo and H.T. Le in Vietnam

:The present study aimed to determine the antimicrobial activity and chemical composition of leaves-extracted essential oil of Leoheo domatiophorus Chaowasku, D.T. Ngo and H.T. Le (L. domatiophorus), including antibacterial, antimycotic, antitrichomonas and antiviral effects. The essential oil was obtained using hydrodistillation, with an average yield of 0.34 ± 0.01% (v/w, dry leaves). There were 52 constituents as identified by GC/MS with available authentic standards, representing 96.74% of the entire leaves oil. The essential oil was comprised of three main components, namely viridiflorene (16.47%), (-)-δ-cadinene(15.58%) and γ-muurolene (8.00%). The oil showed good antimicrobial activities against several species: Gram-positive strains: Staphylococcus aureus (two strains) and Enterococcus faecalis, with Minimum Inhibitory Concentration (MIC) and Minimum Lethal Concentration (MLC) values from 0.25 to 1% (v/v); Gram-negative strains such as Escherichia coli (two strains), Pseudomonas aeruginosa (two strains) and Klebsiella pneumoniae, with MIC and MLC values between 2% and 8% (v/v); and finally Candida species, having MIC and MLC between 0.12 and 4% (v/v).Antitrichomonas activity of the oil was also undertaken, showing IC₅₀, IC₉₀ and MLC values of 0.008%, 0.016% and 0.03% (v/v), respectively, after 48h of incubation. The essential oil resultedin being completely ineffective against tested viruses, ssRNA+ (HIV-1, YFV, BVDV, Sb-1, CV-B4), ssRNA- (hRSVA2, VSV), dsRNA (Reo-1), and dsDNA (HSV-1, VV) viruses with EC₅₀ values over 100 µg/mL. This is the first, yet comprehensive, scientific report about the chemical composition and pharmacological properties of the essential oil in L. domatiophorus.

Proapoptotic Activity of Achillea membranacea Essential Oil and Its Major Constituent 1,8-Cineole against A2780 Ovarian Cancer Cells

Among the hundreds of reported Achillea species, A. membranacea (Labill.) DC. is one of the six that grow in Jordan. Many species of this genus are used in folk medicine to treat a variety of ailments and several biological and pharmacological activities have been ascribed to their essential oil (EO). For this study, the EO obtained from a specimen of A. membranacea grown in Jordan was analyzed by GC-MS. Ninety-six compounds were detected, of which oxygenated monoterpenes was the predominant class (47.9%), followed by non-terpene derivatives (27.9%), while sesquiterpenes represented 14.2% of the total composition. The most abundant compound in the EO was 1,8-cineole (21.7%). The cytotoxic activity of the EO was evaluated against three cancer cell lines (MCF7, A2780 and HT29), and one normal fibroblast cell line (MRC5) by MTT assay. Significant growth inhibition was observed in EO-exposed A2780 and HT29 cells (IC50 = 12.99 and 14.02 μg/mL, respectively), while MCF7 and MRC5 were less susceptible. The EO induced apoptosis and increased the preG1 events in A2780 cells. 1,8-Cineole, the major constituent of the EO, exhibited submicromolar cytotoxicity against A2780 cells, and was 42 times more selective against MRC5 cells. Its cytotoxicity against A2780 cells was comparable with that of doxorubicin, but 1,8-cineole was more selective for MRC5 normal cells. Interestingly, 1,8-cineole enhanced apoptosis in A2780, and caused a remarkable dose-dependent increase in preG1 events. Thus, 1,8-cineole has demonstrated promising cytotoxic and proapoptotic properties.

Protective Effects of Phenylpropanoids and Phenylpropanoid-rich Essential Oils on the Cardiovascular System

BACKGROUND

Cardiovascular diseases are the leading cause of global mortality with a tendency to increase due to population ageing as well as an increase in associated risk factors. Although current therapies improve survival rates, they are associated with several side effects, thus justifying the development of novel preventive and/or therapeutic approaches. In this way, plant metabolites such as essential oils have emerged as promising agents due to their biological effects.

OBJECTIVE

Bearing in mind that several essential oils are characterized by high amounts of phenylpropanoids, which may play a crucial role in the activity of these volatile extracts, a comprehensive and systematic review focusing on the cardiovascular effects of phenylpropanoid-rich essential oils is presented.

METHODS

Popular search engines including PubMed, Science Direct, Scopus and Google Scholar were consulted and papers from 2000 onwards were selected. Non-volatile phenylpropanoids were not considered in this review.

RESULTS

A compilation of the current knowledge on this thematic pointed out beneficial effects for volatile phenylpropanoids namely hypotensive, vasorelaxant, antiplatelet aggregation, antidyslipidaemic and antidiabetic, as well as protective properties against ischemia/reperfusion injury and heart hypertrophy.

CONCLUSION

A better understanding of the protective effects of phenylpropanoids on the cardiovascular system is presented, thus paving the way towards future research on plant-based therapies for cardiovascular diseases.

Lime (Citrus aurantifolia (Christm.) Swingle) Essential Oils: Volatile Compounds, Antioxidant Capacity, and Hypolipidemic Effect

Lime peels are mainly obtained from the byproducts of the juice manufacturing industry, which we obtained and used to extract essential oil (2.3%) in order to examine the antioxidant and hypolipidaemic effects. We identified 60 volatile compounds of lime essential oil (LEO) with GC/MS, of which the predominant constituents were limonene, γ-terpinene, and β-pinene. Lime essential oil was measured according to the DPPH assay and ABTS assay, with IC₅₀ values of 2.36 mg/mL and 0.26 mg/mL, respectively. This study also explored the protective effects of LEO against lipid-induced hyperlipidemia in a rat model. Two groups of rats received oral LEO in doses of 0.74 g/100 g and 2.23 g/100 g with their diets. Eight weeks later, we found that the administration of LEO improved the serum total cholesterol, triglyceride, low-density lipoprotein cholesterol, alanine aminotransferase, and aspartate transaminase levels in the hyperlipidemic rats (p < 0.05). Simultaneously, the LEO improved the health of the rats in terms of obesity, atherogenic index, and fatty liver.

Anticancer Properties of Essential Oils and Other Natural Products

Essential oils are secondary metabolites with a key-role in plants protection, consisting primarily of terpenes with a volatile nature and a diverse array of chemical structures. Essential oils exhibit a wide range of bioactivities, especially antimicrobial activity, and have long been utilized for treating various human ailments and diseases. Cancer cell prevention and cytotoxicity are exhibited through a wide range of mechanisms of action, with more recent research focusing on synergistic and antagonistic activity between specific essential oils major and minor components. Essential oils have been shown to possess cancer cell targeting activity and are able to increase the efficacy of commonly used chemotherapy drugs including paclitaxel and docetaxel, having also shown proimmune functions when administered to the cancer patient. The present review represents a state-of-the-art review of the research behind the application of EOs as anticancer agents both in vitro and in vivo. Cancer cell target specificity and the use of EOs in combination with conventional chemotherapeutic strategies are also explored.