Effects of carvacrol on human fibroblast (WS-1) and gastric adenocarcinoma (AGS) cells in vitro and on Wistar rats in vivo

Carvacrol as a food additive: Toxicological aspects and the role of nanotechnology in enhancing its antimicrobial and antioxidant properties

Carvacrol (CAR), a phenolic monoterpene found in essential oils, shows promise as a food additive due to its antimicrobial and antioxidant properties. Challenges like volatility and strong aroma necessitate innovative approaches for its use, with nanotechnology offering solutions through improved solubility and controlled release. CAR-loaded nanoparticles (NPs) exhibit enhanced antimicrobial and antioxidant activity, presenting a novel approach for food preservation. However, limited toxicological data, particularly for nanoencapsulated forms of CAR, highlights the need for comprehensive safety assessments. While studies indicate varying effects of CAR, with high concentrations showing cytotoxicity and genotoxicity, lower doses appear safe in animal models and human trials. This review highlights the multifaceted role of CAR in food applications and emphasizes the importance of understanding its toxicological profile for well-informed use in the food industry. Furthermore, the use of nanotechnology is explored to enhance the application of CAR in foods.

Developmental toxicity and estrogenic activity of antimicrobial phenolic-branched fatty acids using in silico simulations and in vivo and in vitro bioassay

Due to the growing safety and environmental concerns associated with biocides, phenolic-soy branched chain fatty acids (phenolic-soy BCFAs) are synthesized as new bio-based antimicrobial agents. Safety evaluation is essential before the wide adoption of these new antimicrobial products. This study was initiated to evaluate the safety of four phenolic-soy BCFAs (with phenol, thymol, carvacrol, or creosote branches). Methyl-branched iso-oleic acid, phenol, and creosote were included in the study as controls. In silico toxicity simulation tools predicted that the phenolic BCFAs had much higher toxicities to aquatic organisms than free phenolics did, while the opposite was predicted for rats. The developmental toxicity of four phenolic-soy BCFAs was assessed using an in vivo chicken embryonic assay. Results showed that creosote-soy BCFA had much lower mortality rates than creosote at the same dosages. Additionally, creosote-soy BCFA and methyl-branched iso-oleic acid induced minimal estrogenic activity in the concentration range of 10 nM - 1 µM. Carvacrol-soy BCFA treatments significantly increased (p < 0.05) oxidative stress levels with higher thiobarbituric acid reactive substances in the livers of chicken embryos. Altogether, the phenolic-soy BCFAs, especially creosote-soy BCFA, reported in this study are potentially promising and safer bio-based antimicrobial products.

The recent discovery of a promising pharmacological scaffold derived from carvacrol: A review

Carvacrol, called CA, is a dynamic phytoconstituent characterized by a phenol ring abundantly sourced from various natural reservoirs. This versatile scaffold serves as a pivotal template for the design and synthesis of novel drug molecules, harboring promising biological activities. The active sites positioned at C-4, C-6, and the hydroxyl group (-OH) of CA offer fertile ground for creating potent drug candidates from a pharmacological standpoint. In this comprehensive review, we delve into diverse synthesis pathways and explore the biological activity of CA derivatives. We aim to illuminate the potential of these derivatives in discovering and developing efficacious treatments against a myriad of life-threatening diseases. By scrutinizing the structural modifications and pharmacophore placements that enhance the activity of CA derivatives, we aspire to inspire the innovation of novel therapeutics with heightened potency and effectiveness.

Research into how carvacrol and metformin affect several human proteins in a hyperglycemic condition: A comparative study in silico and in vitro

Carvacrol (CV) is an organic compound found in the essential oils of many aromatic herbs. It is nearly unfeasible to analyze all the current human proteins for a query ligand using in vitro and in vivo methods. This study aimed to clarify whether CV possesses an anti-diabetic feature via Docking-based inverse docking and molecular dynamic (MD) simulation and in vitro characterization against a set of novel human protein targets. Herein, the best poses of CV docking simulations according to binding energy ranged from -7.9 to -3.5 (kcal/mol). After pathway analysis of the protein list through GeneMANIA and WebGestalt, eight interacting proteins (DPP4, FBP1, GCK, HSD11β1, INSR, PYGL, PPARA, and PPARG) with CV were determined, and these proteins exhibited stable structures during the MD process with CV. In vitro application, statistically significant results were achieved only in combined doses with CV or metformin. Considering all these findings, PPARG and INSR, among these target proteins of CV, are FDA-approved targets for treating diabetes. Therefore, CV may be on its way to becoming a promising therapeutic compound for treating Diabetes Mellitus (DM). Our outcomes expose formerly unexplored potential target human proteins, whose association with diabetic disorders might guide new potential treatments for DM.

Polyphenolic Nanomedicine Regulating Mitochondria REDOX for Innovative Cancer Treatment

Cancer remains a highly lethal disease globally. The approach centered on REDOX-targeted mitochondrial therapy for cancer has displayed notable benefits. Plant polyphenols exhibit strong REDOX and anticancer properties, particularly by affecting mitochondrial function, yet their structural instability and low bioavailability hinder their utility. To overcome this challenge, researchers have utilized the inherent physical and chemical characteristics of polyphenols and their derivatives to develop innovative nanomedicines for targeting mitochondria. This review examines the construction strategies and anticancer properties of various types of polyphenol-based biological nanomedicine for regulating mitochondria in recent years, such as polyphenol self-assembly, metal-phenol network, polyphenol-protein, polyphenol-hydrogel, polyphenol-chitosan, and polyphenol-liposome. These polyphenolic nanomedicines incorporate enhanced features such as improved solubility, efficient photothermal conversion capability, regulation of mitochondrial homeostasis, and ion adsorption through diverse construction strategies. The focus is on how these polyphenol nanomedicines promote ROS production and their mechanism of targeting mitochondria to inhibit cancer. Furthermore, it delves into the benefits and applications of polyphenolic nanomedicine in cancer treatments, as well as the challenges for future research.

Effects of essential oil of Origanum onites and its major component carvacrol on the expression of toxicity pathway genes in HepG2 cells

BACKGROUND

Origanum species have been used in various commercial constructions as a remedy against burns and wounds, agriculture, alcoholic drinks, fragrance, and flavoring substances of food products. The essential oil of Origanum onites L. (EOOO) and its component carvacrol (CV) possesses a wide range of biological activities including anti-cancer activity.

PURPOSE

The purpose of this study was to investigate the growth inhibitory activity of the essential oil and its major component CV and then hepatotoxicity pathway-related genes in HepG2 cells.

METHODS

The effects of the EOOO and CV on cell growth and mRNA expressions of 84 hepatotoxicity pathway-related genes were investigated in HepG2, using trypan blue exclusion/ bromodeoxyuridine (BrdU) incorporation tests and real-time-polymerase chain reaction (RT-PCR) array, respectively.

RESULTS

The EOOO and CV inhibited cell growth with IC50 values of 0.08 µg/mL and 45 µg/mL, respectively, after 24 h. Real-time, reverse-transcription-polymerase chain reaction (RT2-PCR) array analysis revealed that expressions of 32 genes out of 84 were changed at least 2-fold or more in the EOOO-treated cells. Among them, expression levels of 17 genes were elevated, while expression levels of 15 genes were diminished. Furthermore, after exposure of cells to 45 µg/mL of CV, the expression of 8 genes was increased while the other 8 genes were decreased. Both the EOOO and carvacrol affected the expression of 48 genes of HepG2 cells which are involved in the hepatotoxicity pathway, indicating their hepatoprotective and possible anti-hepatocarcinogenic effects.

CONCLUSION

The present study demonstrates that the essential oil of Origanum onites and carvacrol can be used in various applications such as anticancer or herbal drugs, since its non-hepatotoxicity.

An Overview of the Spices Used for the Prevention and Potential Treatment of Gastric Cancer

Gastric cancer (GC) ranks third in terms of cancer-related deaths and is the fifth most commonly diagnosed type of cancer. Its risk factors include Helicobacter pylori infection, Epstein-Barr virus infection, the consumption of broiled and charbroiled animal meats, salt-preserved and smoke-enhanced foods, alcohol drinking, tobacco smoking, exposure to ionizing radiation, and positive family history. The limited effectiveness of conventional therapies and the widespread risk factors of GC encourage the search for new methods of treatment and prevention. In the quest for cheap and commonly available medications, numerous studies focus on herbal medicine, traditional brews, and spices. In this review, we outline the potential use of spices, including turmeric, ginger, garlic, black cumin, chili pepper, saffron, black pepper, rosemary, galangal, coriander, wasabi, cinnamon, oregano, cardamom, fenugreek, caraway, clove, dill, thyme, Piper sarmentosum, basil, as well as the compounds they contain, in the prevention and treatment of GC. We present the potential molecular mechanisms responsible for the effectivity of a given seasoning substance and their impact on GC cells. We discuss their potential effects on proliferation, apoptosis, and migration. For most of the spices discussed, we also outline the unavailability and side effects of their use.

N-Acetylcysteine may exert hepatoprotective effect by regulating Meteorin-Like levels in Adriamycin-induced liver injury

Adriamycin (ADR) is an important chemotherapeutic drug, but it has serious side effects such as hepatotoxicity. This study aimed to evaluate whether N-acetylcysteine (NAC) has hepatoprotective effects against ADR-induced hepatotoxicity in rats. In addition, it was aimed to determine how Meteorin-Like (MtrnL), which has pleiotropic effects on immunology, inflammation, and metabolism, is affected by ADR and/or NAC applications in liver tissue. 28 rats were randomly assigned to one of four equal groups in the study: control (no treatment), NAC (150 mg/kg/day of NAC intraperitoneally (i.p), ADR (15 mg/kg only on the first day of the experiment), and ADR + NAC (ADR 15 mg/kg on the first day of the experiment + 150 mg/kg/day NAC i.p). After 15 days, liver enzyme levels in serum, oxidant/antioxidant parameters in liver tissue, histopathological changes, caspase 3 (Casp3) and heat shock protein 70 (HSP-70) immunoreactivities, and MtrnL levels were examined. Histopathological changes, liver enzyme levels, as well as HSP-70, and Casp3 immunoreactivities increased due to ADR application. Additionally, MtrnL levels in liver tissue were significantly increased as a result of ADR application. However, it was detected that the NAC application significantly regulated the ADR-induced changes. Furthermore, it was determined that NAC administration regulated the changes in ADR-induced oxidative stress parameters. We propose that NAC may exert a hepatoprotective effect by regulating ADR-induced altered oxidative stress parameters, MtrnL levels, Casp3, and HSP-70 immunoreactivities in the liver.

Synergistic antibacterial activity of carvacrol loaded chitosan nanoparticles with Topoisomerase inhibitors and genotoxicity evaluation

The increasing prevalence of antibiotic resistant bacteria is a significant healthcare crisis with substantial socioeconomic impact on global community. The development of new antibiotics is both costly and time-consuming prompting the exploration of alternative solutions such as nanotechnology which represents opportunities for targeted drug delivery and reduced MIC. However, concerns have arisen regarding genotoxic effects of nanoparticles on human health necessitating an evaluation of nanoparticle induced DNA damage. This study aimed to investigate the antibacterial potential of already prepared, characterized chitosan nanoparticles loaded with carvacrol and their potential synergism with Topoisomerase II inhibitors against S. aureus, E. coli and S. typhi using agar well diffusion, microdilution and checkerboard method. Genotoxicity was assessed through comet assay. Results showed that both alone and drug combinations of varying concentrations exhibited greater zones of inhibition at higher concentrations. Carvacrol nanoparticles combined with ciprofloxacin and doxorubicin significantly reduced MIC compared to the drugs used alone. The MIC50 values for ciprofloxacin were 35.8 µg/ml, 48.74 µg/ml, 35.57 µg/ml while doxorubicin showed MIC50 values of 20.79 µg/ml, 34.35 µg/ml, 25.32 µg/ml against S. aureus, E. coli and S. typhi respectively. The FICI of ciprofloxacin and doxorubicin with carvacrol nanoparticles found ≤ 0.5 Such as 0.44, 0.44,0.48 for ciprofloxacin and 0.45, 0.45, 0.46 for doxorubicin against S. aureus, E. coli and S. typhi respectively revealed the synergistic effect. The analysis of comet assay output images showed alteration of DNA at high concentrations. Our results suggested that carvacrol nanoparticles in combination with Topoisomerase inhibitors may prevent and control the emergence of resistant bacteria with reduced dose.

Phytochemical Characterization and Biological Evaluation of Origanum vulgare L. Essential Oil Formulated as Polymeric Micelles Drug Delivery Systems

This study presents phytochemical characterization and biological evaluation of Origanum vulgare L. essential oil (OEO) formulated as polymeric micelles drug delivery systems as a possible non-invasive approach for the management of skin tags. GC-MS analysis of Romanian OEO revealed the identification and quantification of 43 volatile compounds (thymol and carvacrol being the main ones). The antioxidant activity was shown by four consecrated methods: CUPRAC, ABTS, ORAC and DPPH. OEO was incorporated by micellar solubilization into a binary hydrogel based on a Pluronic F 127/L 31 block-copolymers mixture. The pH, consistency, spreadability, particle size, polydispersity index and zeta potential of the OEO-loaded poloxamer-based binary hydrogel (OEO-PbH) were investigated. OEO-PbH was skin compatible in terms of pH and exhibited adequate spreadability and consistency. The minimal inhibitory concentrations of the tested OEO were similar to those obtained for the formulation, lower (2.5 µg/mL) for yeast and higher (40-80 µg/mL) for Gram-negative bacilli. As keratinocytes are among main components of skin tags, an in vitro evaluation was conducted in order to see the effect of the formulation against HaCaT human keratinocytes. OEO-PbH decreased HaCaT cells migration and proliferation and elicited a cytotoxic and pro-apoptotic effect in a dose- and time-dependent manner. No harmful effect on the viability of dendritic cells (DCs) was detected following the incubation with different concentrations (0-200 µg/mL) of the 5% formulation. Treatment in inflammatory DCs (+LPS) indicated a decrease in cytokine production of IL-6, TNF-α and IL-23 but no significant effect on IL-10 in any of the tested concentrations.

Anti-Inflammatory and Antioxidant Effects of Carvacrol on N-Methyl-N′-Nitro-N-Nitrosoguanidine (MNNG) Induced Gastric Carcinogenesis in Wistar Rats

Carvacrol is a dietary polyphenol from Lamiaceae plants that has been shown to possess a wide range of biological activities including antioxidant and antitumor effects. This study aimed to investigate its anti-inflammatory and antioxidant effects on N-methyl-N′-nitro-N-nitrosoguanidine (MNNG) induced gastric carcinogenesis in Wistar rats. Forty-nine rats were randomly assigned to four treatment and three control groups. Over 60 days, MNNG (200 mg/kg BW) was orally applied to animals of groups 1–5 while the rats in groups 2–5 also received different doses of carvacrol (10, 25, 50, and 100 mg/kg BW, respectively) until the end of the experiment. Group 6 rats were treated with 100 mg/kg BW carvacrol and no MNNG whereas group 7 was the control group without any treatment. After the euthanasia of all rats, the inflammatory cytokines and oxidative stress parameters were assessed in the blood and tissues. The expression of caspase 9, Bax, and Bcl-2 proteins in the stomach tissues were investigated through histopathological examinations. Statistically significant differences were observed in the body weight, oxidative stress, and inflammation parameters of groups 1 to 6 compared to group 7 (p ≤ 0.001). Animals in MNNG groups 2 and 3 treated with the low dose carvacrol (10 and 25 mg/kg BW) showed significantly reduced oxidative stress, inflammation, and apoptotic effect compared to animals of the MNNG groups receiving increased doses of carvacrol (50 and 100 mg/kg BW) or no carvacrol. Rats exposed to MNNG exhibited gastric cancer cells in several areas. In the MNNG group receiving 100 mg/kg BW carvacrol, the inflammatory cell infiltration was observed in gastric mucosal and submucosal areas whereas MNNG rats supplemented with 10 and 25 mg/kg BW carvacrol showed no pathological alterations of the gastric cells. The results of this study indicate that significant antioxidant and anti-inflammatory effects induced by carvacrol at doses of 10 and 25 mg/kg BW interfered with gastric carcinogenesis induced by MNNG in Wistar rats as well as provide hepatoprotection. However, high doses of carvacrol (50 and 100 mg/kg BW) increased oxidative stress, inflammation, and apoptosis.

Carvacrol protects against carbonyl osmolyte-induced structural modifications and aggregation to serum albumin: Insights from physicochemical and molecular interaction studies

The robust use of osmolytes (i.e., polyols and sugars) in the key therapeutic regimens/formulations has questioned their impact beyond the stability of therapeutic proteins as these osmolytes trigger structural alterations into proteins including misfolding and subsequent aggregation into amyloid fibrils. Therefore, the current study is the first to delineate the inhibitory effect of carvacrol (CRV) on the carbonyl osmolyte-induced aggregation as well as structural alterations to the bovine serum albumin (BSA) via a set of physicochemical as well as artificial intelligence (AI)-based molecular docking studies. Our initial findings from physicochemical investigations revealed that CRV exhibits substantial protection to BSA under carbonyl osmolyte stress as evident by the compromised hyperchromicity, Schiff's bases, carbonyl and hydroxymethyl furfural content, reduced fluorescent signals, low Rayleigh scattering and prevention of covalent modifications at Lys and Arg residues. The protection against aggregate formation by CRV was further confirmed through the reduced amyloid-specific congo red absorbance as well as fluorescent signals recorded after adding the fibril-specific extrinsic fluorophore probes (i.e., ThT and ANS). The AI-based molecular docking analysis further revealed that CRV (ΔG: -4.96 kcal/mol) competes with d-fructose (ΔG: -4.40 kcal/mol) to mask the Lys and Arg residues to restrict the osmolyte-mediated protein modifications. In conclusion, CRV exhibits substantial protective impact against carbonyl osmolyte-induced structural alterations and protein misfolding and aggregation.

A Narrative Review of the Antitumor Activity of Monoterpenes from Essential Oils: An Update

Monoterpenes are a group of natural products that have been widely studied due to their therapeutic potential against various pathologies. These compounds are abundant in the chemical composition of essential oils. Cancer is a term that covers more than 100 different types of malignant diseases and is among the leading causes of death in the world. Therefore, the search for new pharmacotherapeutic options applicable to cancer is urgent. In this review, studies on the antitumor activity of monoterpenes found in essential oils were selected, and botanical, chemical, and pharmacological aspects were discussed. The most investigated monoterpenes were carvacrol and linalool with highly significant in vitro and in vivo tumor inhibition in several types of cancers. The action mechanisms of these natural products are also presented and are wildly varied being apoptosis the most prevalent followed by cell cycle impairment, ROS production, autophagy, necroptosis, and others. The studies reported here confirm the antitumor properties of monoterpenes and their anticancer potential against various types of tumors, as demonstrated in in vitro and in vivo studies using various types of cancer cells and tumors in animal models. The data described serve as a reference for the advancement in the mechanistic studies of these compounds and in the preparation of synthetic derivatives or analogues with a better antitumor profile.

Carvacrol Arrests the Proliferation of Hypopharyngeal Carcinoma Cells by Suppressing Ornithine Decarboxylase and Hyaluronidase Activities

Carvacrol, a monoterpene known for its pharmacological activities, is present in the essential oil of Origanum majorana, Origanum vulgare, Thymus vulgaris, and Lippia graveolens. It is used in food as a flavoring and preservative agent in cosmetics and medicines because of its useful bioactivities in clinical practice. However, carvacrol was not much explored for its anticancer potential. Targeting enzymes involved in carcinogenesis, such as ornithine decarboxylase (ODC), cyclooxygenase-2 (COX-2), lipoxygenase-5 (LOX-5), and hyaluronidase (HYAL) by monoterpenes are amongst the efficient approaches for cancer prevention and treatment. In this study, the efficacy of carvacrol was investigated against deregulated cancer biomarkers/targets in organ-specific human cancer cell lines (FaDu, K562, and A549) utilizing in vitro, in silico, and in vivo approaches. The efficacy of carvacrol was evaluated on human cancer cell lines using neutral red uptake (NRU), sulpho rhodamine B (SRB), and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assays. The mechanistic study was carried out in cell-based test systems. Further, the potency of carvacrol was confirmed by the quantitative real-time PCR analysis and molecular docking studies. The in vivo anti-tumor potential of carvacrol was performed on mice S-180 model, and the toxicity examination was accomplished through in silico approach. Carvacrol significantly impeded the growth of FaDu, K562, and A549 cell lines with IC₅₀ values ranging from 9.61 ± 0.05 to 81.32 ± 11.83 μM. Further, the efficacy of carvacrol was explored against different cancer targets in FaDu, K562, and A549 cell lines. Carvacrol inhibits the ODC, COX-2, LOX-5, and HYAL activities in FaDu cell line and ODC, COX-2, and HYAL activities in K562 cell line. The results were validated by expression analysis revealing the downregulation of the targeted gene with a significant change in the transcript level of ODC and HYAL in FaDu cell line with a fold change of 1.56 and 1.61, respectively. A non-significant effect of carvacrol was observed on the downstream signaling pathway of PI3K and HIF-1α/vascular endothelial growth factor (VEGF) in FaDu cells. The cell cycle, reactive oxygen species (ROS), mitochondrial membrane potential (MMP), and Annexin V-fluorescein isothiocyanate (FITC) experiments demonstrate that carvacrol induces apoptosis of FaDu cells. Further, the potency of carvacrol was also evaluated in vivo on mice S-180 tumor model, wherein it inhibits tumor growth (72%) at 75 mg/kg body weight (bw). ADMET studies predicted carvacrol as a safe molecule. Overall, carvacrol delayed the growth of FaDu, K562, and A549 cell lines by targeting enzymes involved in the carcinogenesis process. The existence of one hydroxyl group at the para position of carvacrol could be responsible for the anti-proliferative activity. Thus, carvacrol could be used as a pharmacophore to develop a safe and effective multi-targeted anti-cancer medicament.

In vitro antiviral activity of Thymbra spicata L. extract on bovine respiratory viruses (BCoV, BPIV-3, BRSV, BVDV and BoHV-1)

AIMS

Viral pathogens are the primary agents in bovine respiratory disease cases, and there is no direct effective antiviral drug application. Thymbra is a genus of oregano commonly found in Turkey. The primary component (34.9%) of the extract obtained from Thymbra spicata L. is the carvacrol which is used in traditional medicine. This study evaluates the potential antiviral activity and inactivation efficiency of T. spicata L. extract against bovine respiratory viruses, including BCoV, BPIV-3, BRSV, BVDV and BoHV-1.

METHODS AND RESULTS

To evaluate its effect on viral replication, viral titres were taken from infected cells treated with non-cytotoxic T. spicata L. extract concentrations (0.75% and 1.5%, 1.32 and 2.64 µg/ml of carvacrol as active ingredient, respectively) and compared to non-treated infected cells. The viruses were treated directly with 1.5% T. spicata L. extract, and the viral titres were evaluated at certain time points to determine the efficiency of direct inactivation. The number of infectious virions for BCoV, BPIV-3, BRSV, BVDV and BoHV-1 treated with 1.5% T. spicata L. extract were decreased by 99.44%, 100.0%, 94.38%, 99.97% and 99.87%, respectively.T. spicata L. extract strongly inhibits the replication of mentioned viruses in a dose-dependent manner in vitro. In addition, T. spicata L. extract shared direct inactivation efficiency on the mentioned viruses in a time-dependent manner.

CONCLUSION

This study shows the antiviral efficiency of T. spicata L. on BRD-related viral agents for the first time. The oregano species T. spicata and its main component, carvacrol, may have a potential for antiviral activity in the alternative treatment of respiratory viral diseases in cattle.

SIGNIFICANCE AND IMPACT OF THE STUDY

Given the similarity of replication strategies, obtained data suggest the possible efficiency of T. spicata L. on human respiratory viruses.

Biomedical Effects of the Phytonutrients Turmeric, Garlic, Cinnamon, Graviola, and Oregano: A Comprehensive Review

Phytonutrients are plant foods that contain many natural bioactive compounds, called phytochemicals, which show specific biological activities. These phytonutrients and their phytochemicals may play an important role in health care maintaining normal organism functions (as preventives) and fighting against diseases (as therapeutics). Phytonutrients’ components are the primary metabolites (i.e., proteins, carbohydrates, and lipids) and phytochemicals or secondary metabolites (i.e., phenolics, alkaloids, organosulfides, and terpenes). For years, several phytonutrients and their phytochemicals have demonstrated specific pharmacological and therapeutic effects in human health such as anticancer, antioxidant, antiviral, anti-inflammatory, antibacterial, antifungal, and immune response. This review summarizes the effects of the most studied or the most popular phytonutrients (i.e., turmeric, garlic, cinnamon, graviola, and oregano) and any reported contraindications. This article also presents the calculated physicochemical properties of the main phytochemicals in the selected phytonutrients using Lipinski’s, Veber’s, and Ghose’s rules. Based on our revisions for this article, all these phytonutrients have consistently shown great potential as preventives and therapeutics on many diseases in vitro, in vivo, and clinical studies.

Antitumor Effects of Carvacrol and Thymol: A Systematic Review

Background: It is estimated that one in five people worldwide faces a diagnosis of a malignant neoplasm during their lifetime. Carvacrol and its isomer, thymol, are natural compounds that act against several diseases, including cancer. Thus, this systematic review aimed to examine and synthesize the knowledge on the antitumor effects of carvacrol and thymol.

Methods: A systematic literature search was carried out in the PubMed, Web of Science, Scopus and Lilacs databases in April 2020 (updated in March 2021) based on the PRISMA 2020 guidelines. The following combination of health descriptors, MeSH terms and their synonyms were used: carvacrol, thymol, antitumor, antineoplastic, anticancer, cytotoxicity, apoptosis, cell proliferation, in vitro and in vivo. To assess the risk of bias in in vivo studies, the SYRCLE Risk of Bias tool was used, and for in vitro studies, a modified version was used.

Results: A total of 1,170 records were identified, with 77 meeting the established criteria. The studies were published between 2003 and 2021, with 69 being in vitro and 10 in vivo. Forty-three used carvacrol, 19 thymol, and 15 studies tested both monoterpenes. It was attested that carvacrol and thymol induced apoptosis, cytotoxicity, cell cycle arrest, antimetastatic activity, and also displayed different antiproliferative effects and inhibition of signaling pathways (MAPKs and PI3K/AKT/mTOR).

Conclusions: Carvacrol and thymol exhibited antitumor and antiproliferative activity through several signaling pathways. In vitro, carvacrol appears to be more potent than thymol. However, further in vivo studies with robust methodology are required to define a standard and safe dose, determine their toxic or side effects, and clarify its exact mechanisms of action.

This systematic review was registered in the PROSPERO database (CRD42020176736) and the protocol is available at https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=176736.

Molecules Present in Plant Essential Oils for Prevention and Treatment of Colorectal Cancer (CRC)

Essential oils (EOs) are a complex mixture of hydrophobic and volatile compounds synthesized from aromatic plants, commonly present in the human diet. In recent years, many in vitro studies have suggested possible anticancer properties of single EO compounds, on colorectal cancer (CRC) cells. However, the majority of these studies did not compare the effects of these compounds on normal and cancer colon cells. By using NCM-460, a normal human mucosal epithelial cell line, Caco-2, a human colon epithelial adenocarcinoma cell line, and SW-620, colon cancer cells derived from lymph node metastatic site, we identified cinnamaldehyde, derived from cinnamon EO and eugenol, derived from bud clove EO, as compounds with a specific anticancer action selectively targeting the transformed colonic cells. Both cinnamaldehyde (75 µM) and eugenol (800 µM), after 72 h of treatment, were capable to induce apoptosis, necrosis and a cell cycle slowdown in Caco-2 and in SW-620, but not in NCM-460 cells. If associated with a targeted delivery to the colon, these two compounds could prove effective in the prevention or treatment of CRC.

In vitro cytotoxicity of cardamom oil, lemon oil, and jasmine oil on human skin, gastric, and brain cancer cell line

Objective

The main objective of the study was to evaluate the cytotoxicity of selected essential oils on human skin, gastric, and brain cancer cell lines using microculture tetrazolium test.

Materials and Methods

Phytochemical analysis, as well as acute oral toxicity tests, was carried out in female albino mice with cardamom oil, lemon oil, and jasmine oil according to the Organization for Economic Co-operation and Development guidelines 425. Anticancer activities of the above test drugs were performed using human cancer cell lines. The studies were carried out at Skanda Life Sciences Pvt. Ltd., Bengaluru.

Results

Phytochemical analysis has shown the presence of carbohydrates and flavonoids in cardamom oil. While lemon oil has shown the presence of carbohydrates, flavonoids, steroids, terpenoids, and tannins, jasmine oil has shown the presence of carbohydrates, alkaloids, flavonoids, steroids, terpenoids, and glycosides. Toxicity studies showed that cardamom oil, lemon oil, and jasmine oil were all found to be safe up to 2000 mg/kg body weight. Results have shown that lemon oil exhibited the strongest cytotoxicity toward three human cancer cell lines, namely skin cancer (A431), gastric cancer (MKN-45), and brain cancer (U-87 MG) cell lines, with higher IC₅₀ values of 62.82 μg/ml, 220.9 μg/ml, and 440.1 μg/ml compared to standard. Jasmine oil exhibited the strongest cytotoxicity toward skin cancer and brain cancer cell lines, whereas cardamom oil has shown stronger cytotoxicity only toward skin cancer cell line but did not show any level of inhibition of growth of brain and gastric cancer cells.

Conclusion

Our study reveals that lemon oil, jasmine oil, and cardamom oil possess potent antitumor activity compared to standard. At different concentrations, lemon oil has shown statistically significant (***P < 0.0001) anticancer activity toward all the three human cancer cell lines. While jasmine oil has shown statistically significant (***P < 0.0001) anticancer activity toward skin and brain cancer cell line, cardamom oil has also shown statistically significant (***P < 0.0001) anticancer activity but only toward skin cancer cell line.

Synthesis and Biological Evaluation of Carvacrol-Based Derivatives as Dual Inhibitors of H. pylori Strains and AGS Cell Proliferation

This study reports on the synthesis, structural assessment, microbiological screening against several strains of H. pylori and antiproliferative activity against human gastric adenocarcinoma (AGS) cells of a large series of carvacrol-based compounds. Structural analyses consisted of elemental analysis, 1H/13C/19F NMR spectra and crystallographic studies. The structure-activity relationships evidenced that among ether derivatives the substitution with specific electron-withdrawing groups (CF3 and NO2) especially in the para position of the benzyl ring led to an improvement of the antimicrobial activity, whereas electron-donating groups on the benzyl ring and ethereal alkyl chains were not tolerated with respect to the parent compound (MIC/MBC = 64/64 µg/mL). Ester derivatives (coumarin-carvacrol hybrids) displayed a slight enhancement of the inhibitory activity up to MIC values of 8-16 µg/mL. The most interesting compounds exhibiting the lowest MIC/MBC activity against H. pylori (among others, compounds 16 and 39 endowed with MIC/MBC values ranging between 2/2 to 32/32 µg/mL against all the evaluated strains) were also assayed for their ability to reduce AGS cell growth with respect to 5-Fluorouracil. Some derivatives can be regarded as new lead compounds able to reduce H. pylori growth and to counteract the proliferation of AGS cells, both contributing to the occurrence of gastric cancer.

Antiviral mechanism of carvacrol on HSV-2 infectivity through inhibition of RIP3-mediated programmed cell necrosis pathway and ubiquitin-proteasome system in BSC-1 cells

BACKGROUND

Carvacrol, as the major components of aromatic plants used for treating human skin diseases including origanum, Satureja, thymus, and coridothymus species, presented a kind of antiviral activity. To explore the mechanisms of carvacrol against herpes simplex virus (HSV) in vitro.

METHOD

The BSC-1 cells model of HSV infection was established, and from the two aspects of viral replication level and cell death pathway, the antiviral effects of carvacrol on HSV infected cells were also evaluated by plaque assay under the three modes including prevention, treatment, and direct inactivation.

RESULTS

In the three ways, the half-maximal effective concentration (EC50) of 2% true carvacrol solution on HSV-2 infected cells were severally 0.43, 0.19 and 0.51 mmol/L, and the corresponding therapeutic index (TI) were 4.02, 9.11 and 3.39, respectively. It's the opposite of the increased levels caused by HSV-2 infection, that both the expressions at the transcription genes and protein levels of virus own replication key factors (including ICP4, ICP27, VP16, gB, and UL30) and cytokines (including RIP3, TNF-α, and MLKL) of infected cells treated with carvacrol were dose-dependently inhibited. Besides, HSV-2 infection can cause the decrease of intracellular protein ubiquitination level, and carvacrol can reverse the ubiquitination decrease level caused by HSV-2 infection.

CONCLUSION

Carvacrol exhibits significant antiviral activity by inhibiting the HSV-2 proliferation process and HSV-2-induced TNF-α increasing levels, decreasing RIP3 and MLKL protein expressions through the intracellular RIP3-mediated programmed cell necrosis pathway. In addition, carvacrol also may exhibit anti-HSV-2 activity by reversing the ubiquitination decrease level caused by HSV-2 infection on the ubiquitin-proteasome system, which provides insights into the molecular mechanism.

Effect of Carvacrol, TRP Channels Modulator, on Cardiac Electrical Activity

Despite the wide application of carvacrol (CAR) in medicines, dietary supplements, and foods, there is still insufficient electrophysiological data on the mechanisms of action of CAR, particularly with regard to heart function. Therefore, in this study, we attempted to elucidate whether CAR, whose inhibitory effect on both cardiac and vascular TRPM7 and L-type Ca²⁺ currents has been demonstrated previously, could modify cardiac electrical activity. We used a combination of optical mapping and microelectrode techniques to track the action potentials (APs) and the spread of electrical activity in a Langendorff-perfused rabbit heart model during atrial/endo/epicardial pacing. Simultaneously, ECG recordings were acquired. Because human trials on CAR are still lacking, we tested the action of CAR on human ventricular preparations obtained from explanted hearts. Activation time (AT), AP duration (APD), and conduction velocity maps were constructed. We demonstrated that at a low concentration (10 μM) of CAR, only marginal changes in the AP parameters were observed. At higher concentrations (≥100 μM), a decrease in AP upstroke velocity (dV/dt_max), suggesting inhibition of Na⁺ current, and APD (at 50 and 90% repolarization) was detected; also slowing in the spread of electrical signals via the atrioventricular node was observed, suggesting impaired functioning of Ca²⁺ channels. In addition, a decrease in the T-wave amplitude was seen on the ECG, suggesting an impaired repolarization process. Nevertheless, those changes occurred without a significant impact on the resting membrane potential and were reversible. We suggest that CAR might play a role in modulating cardiac electrical activity at high concentrations.

Hesperozygis ringens (Benth.) Epling: a study involving extraction, chemical profiling, antioxidant and biological activity

Hesperozygis ringens is a plant of the Lamiaceae family which is restricted to the Southern region of Brazil. It is popularly used as an insecticide, but knowledge on it is very scarce. This study aimed to determine the chemical markers of H. ringens extracts obtained via ultrasound-assisted (UAE-EtOH) and supercritical fluid (SFE-CO₂) extractions. UAE-EtOH and SFE-CO₂ extracts were characterised by UPLC-MS and GC-MS, respectively. Both products had their antioxidant activity, cytotoxicity and genotoxicity evaluated. Twelve compounds were found in the UAE-EtOH extract, including phenolic acids and flavonoids; the SFE-CO₂ extract contained terpenes and phytosterols. The UAE-EtOH extract showed a greater antioxidant activity. Neither extract presented cytotoxicity or genotoxicity against human mononuclear blood cells.