Dietary supplementation with a blend composed of carvacrol, tannic acid derived from Castanea sativa and Glycyrrhiza glabra, and glycerides of medium chain fatty acids for weanling piglets raised in commercial farm.

This study aimed to evaluate the dietary administration of a blend composed of carvacrol, tannic acid derived from Castanea sativa mill and Glycyrrhiza glabra, medium chain fatty acids (MCFAs) glycerides for weanling piglets. An in vitro digestion followed by total phenolic content (TPC) and total antioxidant activity (TAC) assessment was performed before the in vivo application. At weaning, a total of 210 piglets were randomly allocated to two experimental treatments (7 replicates/15 piglets for each replicate). Control group (CTR) was fed a standard basal diet while the treated group (T) was fed the basal diet mixed with 1.500 mg/kg of blend. After in vitro digestion, TPC and TAC evidenced peaks at the end of oral and gastric phases in comparison to the intestinal one in line with the high content of phenolic compound (P < 0.05). Treatment conditioned body weight and average daily gain (P < 0.05), fecal score on 6, 7, and 8 d after weaning (P < 0.05). At 35d, the T group showed a decrease in salivary cortisol compared to CTR (P < 0.05). Duodenum and jejunum sections of T piglets revealed higher villi (P < 0.05), deeper crypts (P < 0.01), and increased V/C ratio (P < 0.01). CTR showed a higher expression of duodenal Occludin (P < 0.05). Jejunal E-cadherin and Occludin were more expressed in T jejunum sections (P < 0.05). Twelve differentially abundant genera were identified in T group caecal samples. Potentially harmful Clostridium sensu stricto 13 was reduced by the treatment (P < 0.05). In conclusion, the tested blend positively affected salivary stress markers and the gut health of weaned piglets.

Carvacrol alleviates CUMS-induced depressive-like behaviors and cognitive impairment by reducing oxidative stress and neuroinflammation in mice.

The present study aimed to evaluate the protective potential of carvacrol against depressive-like behavior and cognitive impairment prompted by chronic unpredictable mild stress (CUMS) in mice. The animals were divided into six groups: Control (non-stressed), CARV (carvacrol at 50 mg/kg, p.o.), FLU (fluoxetine at 10 mg/kg, p.o.), CUMS (stressed), CUMS + CARV and CUMS + FLU, and the groups with CUMS were subjected to different stressors for 28 days. After treatment, mice underwent behavioral testing (open field, forced swimming, sucrose preference, social interaction, novel object recognition and Y-maze) and brain areas were removed for oxidative stress (MDA, nitrite/nitrate and GSH levels) and cytokine (IL-1ß and TNF-α) content assays. The results revealed that CARV administration reversed depressive-like behavior and significantly ameliorated the cognitive deficit induced by CUMS, as well as was able to attenuate oxidative stress (decreased MDA and nitrite/nitrate levels and increased GSH levels). In addition, a significant reduction in hippocampal IL-1ß and TNF-α levels was observed, demonstrating a potential anti-neuroinflammatory activity. Taken together, the antioxidant and anti-inflammatory activities observed in this study indicate that CARV is a promising drug for antidepressant treatment.

Carvacrol Enhance Apoptotic Effect of 5-FU on MCF-7 Cell Line via inhibiting P-glycoprotein: An In-silco and In-vitro Study.

BACKGROUND: P-glycoprotein (P-gp), is an ATP-dependent efflux transporter and overexpressed in cancer cells which is responsible for drug resistance and transportation of anticancer agents out of cells. Hence, P-gp inhibition is a promising way to reverse multi-drug resistance, finding a suitable inhibitor is essential. Carvacrol, an active compound of thyme, has been shown anticancer properties in several types of cancers but the mechanisms underlying this effect remain unclear. Here, we evaluated the inhibitory effects of carvacrol on P-gp by In-silco and in-vitro studies. METHOD: carvacrol was docked against P-gp via autodock vina software to identify the potential binding of this agent. Verapamil, a well-known P-gp inhibitor, was selected as the control ligands. Cell proliferation and apoptosis were assessed using MTT assay and ELISA cell death assay, respectively. RESULTS: It was observed that carvacrol exhibited appropriate affinity (-7 kcal/mol) to drug binding pocket of P-gp when compared with verapamil that showed binding affinities of -8 kcal/mol. The result of MTT assay showed a dose-dependent inhibitory effect of carvacrol and 5-FU. Data of apoptosis assay showed that combining carvacrol with 5-FU increased apoptotic effect of 5-FU 6.7-Fold rather than the control group. This ability to enhance apoptosis is more than the combination of verapamil and 5-FU (4.26-Fold). CONCLUSION: These results provide important evidence that carvacrol may be a promising agent able to overcome P-gp-mediated MDR.

Impact of aliphatic acyl and aromatic thioamide substituents on the anticancer activity of Ru(II)-p-cymene complexes with acylthiourea ligands-in vitro and in vivo studies.

Six different acylthiourea ligands (L1-L6) and their corresponding Ru(II)-p-cymene complexes (P1-P6) were designed to explore the structure-activity relationship of the complexes upon aliphatic chain and aromatic conjugation on the C- and N-terminals, respectively. The compounds were synthesized and adequately characterized using various analytical and spectroscopic techniques. The structures of P2-P6, solved using single crystal X-ray diffraction (XRD), confirmed the neutral monodentate coordination of the S atoms of the acylthiourea ligands to Ru(II) ions. In silico studies showed an increase of lipophilicity for the ligands with an increase in alkyl chain length or aromatic conjugation at the C- or N-terminal, respectively. Subsequently, mitogen-activated protein kinases (MAPK) were predicted as one of the primary targets for the complexes, which showed good binding affinity towards extracellular signal-regulated kinases (ERK1, ERK2 and ERK5), c-Jun N-terminal kinase (JNK) and p38 of the MAPK pathway. Henceforth, the complexes were tested for their anticancer activity in lung carcinoma (A549) and cisplatin-resistant lung carcinoma (cisA549R) cells and human umbilical vein epithelial normal cells (HUVEC). Interestingly, an increase in chain length or aromatic conjugation led to an increase in the activity of the complexes, with P5 (7.73 and 13.04 µM) and P6 (6.52 and 14.45 µM) showing the highest activity in A549 and cisA549R cells, which is better than the positive control, cisplatin (8.72 and 44.28 µM). Remarkably, we report the highest activity yet observed for complexes of the type [(η6-p-cymene)RuIICl2(S-acylthiourea)] in the tested cell lines. Aqueous solution studies showed that complexes P5 and P6 are rapidly hydrolyzed to produce solely aquated species that remained stable for 24 h. Staining assays and flow cytometric analyses of P5 and P6 in A549 cells revealed that the complexes induced apoptosis and arrested the cell cycle predominantly in the S phase. In vivo studies demonstrated the higher toxicity of cisplatin and a comparatively higher survival rate of mice injected with the most active complex P6. Histological analyses revealed that treatment with P6 at high doses of up to 8 mg kg-1 did not cause any palpable damage to the tested organs.

Carvacrol and PPARγ agonist, pioglitazone, affects inhaled paraquat-induced lung injury in rats.

Exposed rats to normal saline and paraquat (PQ) aerosol as control and PQ group, rats exposed to PQ and treated with 20 and 80 mg/kg/day carvacrol, 5 and 10 mg/kg/day pioglitazone, low dose of pioglitazone + carvacrol and 0.03 mg/kg/day dexamethasone (Dexa) for 16 days after the end of PQ exposure were studied (n = 6 in each group). Lung pathological changes, tracheal responsiveness to methacholine and ovalbumin (OVA) as well as transforming growth factor beta (TGF-ß) and interleukin (IL)-6 level in the lung tissue homogenize as well as TGF-ß, IL-6, oxidant and antioxidant levels oxidant and antioxidants were increased in PQ group (p < 0.01 to p < 0.001). Lung pathological changes, tracheal responsiveness to methacholine and OVA as well as TGF-ß, IL-6 oxidant and antioxidant levels were improved in all treated groups except lung pathological changes in treated group with low dose of pioglitazone (p < 0.05 to p < 0.001). The effects of low dose of pioglitazone and carvacrol alone were significantly lower than in the combination group of low dose of pioglitazone + carvacrol (p < 0.05 to p < 0.001). Carvacrol treatment improved inhaled PQ-induced lug injury similar to the effects of dexamethasone. The synergic effect of carvacrol and pioglitazone suggests PPAR-γ receptor mediated effects of carvacrol on inhaled PQ-induced lung injury.

Liposomal Encapsulation of Carvacrol to Obtain Active Poly (Vinyl Alcohol) Films.

Lecithins of different origins and compositions were used for the liposomal encapsulation of carvacrol within the framework of the development of active films for food packaging. Liposomes were incorporated into aqueous polymeric solutions from fully (F) and partially (P) hydrolysed Poly (vinyl alcohol) (PVA) to obtain the films by casting. The particle size distribution and ζ-potential of the liposomal suspensions, as well as their stability over time, were evaluated. Liposomal stability during film formation was analysed through the carvacrol retention in the dried film and the film microstructure. Subtle variations in the size distributions of liposomes from different lecithins were observed. However, the absolute values of the ζ-potential were higher (-52, -57 mV) for soy lecithin (SL) liposomes, followed by those of soy lecithin enriched with phosphatidylcholine (SL-PC) (-43, -50 mV) and sunflower lecithin (SFL) (-33, -38 mV). No significant changes in the liposomal properties were observed during the study period. Lyotropic mesomorphism of lipid associations and carvacrol leakage occurred to differing extents during the film drying step, depending on the membrane lipid composition and surface charge. Liposomes obtained with SL-PC were the most effective at maintaining the stability of carvacrol emulsion during film formation, which led to the greatest carvacrol retention in the films, whereas SFL gave rise to the least stable system and the highest carvacrol losses. P-PVA was less sensitive to the emulsion destabilisation due to its greater bonding capacity with carvacrol. Therefore, P-PVA with carvacrol-loaded SL-PC liposomes has great potential to produce active films for food packaging applications.

Diet, Immunity, and Microbiota Interactions: An Integrative Analysis of the Intestine Transcriptional Response and Microbiota Modulation in Gilthead Seabream (Sparus aurata) Fed an Essential Oils-Based Functional Diet.

Essential oils (EOs) are promising alternatives to chemotherapeutics in animal production due to their immunostimulant, antimicrobial, and antioxidant properties, without associated environmental or hazardous side effects. In the present study, the modulation of the transcriptional immune response (microarray analysis) and microbiota [16S Ribosomal RNA (rRNA) sequencing] in the intestine of the euryhaline fish gilthead seabream (Sparus aurata) fed a dietary supplementation of garlic, carvacrol, and thymol EOs was evaluated. The transcriptomic functional analysis showed the regulation of genes related to processes of proteolysis and inflammatory modulation, immunity, transport and secretion, response to cyclic compounds, symbiosis, and RNA metabolism in fish fed the EOs-supplemented diet. Particularly, the activation of leukocytes, such as acidophilic granulocytes, was suggested to be the primary actors of the innate immune response promoted by the tested functional feed additive in the gut. Fish growth performance and gut microbiota alpha diversity indices were not affected, while dietary EOs promoted alterations in bacterial abundances in terms of phylum, class, and genus. Subtle, but significant alterations in microbiota composition, such as the decrease in Bacteroidia and Clostridia classes, were suggested to participate in the modulation of the intestine transcriptional immune profile observed in fish fed the EOs diet. Moreover, regarding microbiota functionality, increased bacterial sequences associated with glutathione and lipid metabolisms, among others, detected in fish fed the EOs supported the metabolic alterations suggested to potentially affect the observed immune-related transcriptional response. The overall results indicated that the tested dietary EOs may promote intestinal local immunity through the impact of the EOs on the host-microbial co-metabolism and consequent regulation of significant biological processes, evidencing the crosstalk between gut and microbiota in the inflammatory regulation upon administration of immunostimulant feed additives.

Chicken embryonic toxicity and potential in vitro estrogenic and mutagenic activity of carvacrol and thymol in low dose/concentration.

Thymol and carvacrol are phenolic isomers with the potential developmental toxicity and endocrine disruptions (ED) at low concentrations. However, few reports estimated their toxicity and ED below 10-6 M (150 µg/L) (MW of thymol and carvacrol: 150 g/mol). In this study, both chemicals were determined for the developmental toxicity and potential ED at 500 µg/kg and 50 µg/kg using the chicken embryonic assay, potential estrogenic activity (EA) at 10-12 to 10-7 M (1.5 × 10-4 to 15 µg/L) by the MCF-7 cell proliferation assay, mutagenicity at 10-12 to 10-6 M (1.5 × 10-4 to 150 µg/L) by the Ames test, and an in silico method for ED. Carvacrol showed mutagenic risks at 10-7, 10-8, and 10-11 M (15, 1.5, and 0.0015 µg/L) while thymol at 10-6 and 10-8 M (150 and 1.5 µg/L). Carvacrol negatively impacted embryonic growth at 50 µg/kg, with weak EA at 10-8 M (1.5 µg/L). Carvacrol but not thymol had weak EA at 10-12 M (1.5 × 10-4 µg/L). Molecular docking to 14 types of hormone-related receptors revealed that carvacrol had higher binding affinities to two estrogen receptors and the mineralocorticoid receptor than those to thymol. Carvacrol and thymol varied in toxicities due to a different location of one phenolic hydroxyl group.

Dietary administration of cumin-derived cuminaldehyde induce neuroprotective and learning and memory enhancement effects to aging mice.

Cuminaldehyde (CA) is one of the major compounds of the essential oil of Cuminum cyminum. The aim of this study was to evaluate the effects of CA on aging, specifically on spatial learning and memory. To achieve our objective, an in vitro study on SH-SY5Y cells was performed to analyze the neuroprotective effect of CA against dexamethasone using the MTT assay. An in vivo study was performed for evaluation of the spatial learning and memory using Morris water maze (MWM). RT-PCR was performed to quantify the expression of specific genes (Bdnf, Icam and ApoE) in the mice brain. The results obtained showed a neuroprotective effect of CA against dexamethasone-induced neuronal toxicity. The escape latency of CA-treated aged mice was significantly decreased as compared to the water-treated aged mice after 4 days of training in MWM. Moreover, CA treatment up-regulated the gene expression of Bdnf, Icam and ApoE, while it down-regulated the gene expression of IL-6. These findings suggest that CA has a neuroprotective effect, as well as a spatial learning and memory enhancement potential through the modulation of genes coding for neurotrophic factors and/or those implicated in the imbalance of neural circuitry and impairment of synaptic plasticity. Cuminaldehyde (CA) is one of the major compound of the essential oil of Cuminum cyminum. The aim of this study was to evaluate the effects of CA on aging, specifically on spatial learning and memory. To achieve our objective, an in vitro study on SH-SY5Y cells was performed to analyze the neuroprotective effect of CA against dexamethasone using the MTT assay. An in vivo study was performed for evaluation of the spatial learning and memory using Morris water maze (MWM). RT-PCR was performed to quantify the expression of specific genes (Bdnf, Icam and ApoE) in the mice brain. The results obtained showed a neuroprotective effect of CA against dexamethasone-induced neuronal toxicity. The escape latency of CA-treated aged mice was significantly decreased as compared to the water-treated aged mice after 4 days of training in MWM. Moreover, CA treatment up-regulated the gene expression of Bdnf, Icam and ApoE, while it down-regulated the gene expression of IL-6. These findings suggest that CA has a neuroprotective effect, as well as a spatial learning and memory enhancement potential through the modulation of genes coding for neurotrophic factors and/or those implicated in the imbalance of neural circuitry and impairment of synaptic plasticity.

Safety and tolerability of carvacrol in healthy subjects: a phase I clinical study.

This study was designed to assess safety and tolerability of carvacrol in healthy individuals. Subjects were randomly divided into two groups receiving 1 and 2 mg/kg/day carvacrol. Before and after carvacrol administration, routine blood and urine laboratory tests and spirometry were performed for all participants. The results showed that one-month treatment with carvacrol did not significantly affect the measured variables. In the group receiving 1 mg/kg/day carvacrol, calcium, erythrocyte sedimentation rate (ESR), mean cell volume (MCV), hemoglobin (Hb), and hematocrit (HCT) levels were significantly reduced but creatinine phosphokinase (CPK) was significantly increased, after treatment compared to baseline values (p < 0.05-p < 0.001). There was significant reductions in high-density lipoprotein cholesterol (HDL), total bilirubin, amylase, iron, red blood cells (RBC) count, and HCT after one-month treatment with 2 mg/kg/day carvacrol compared to pretreatment values (p < 0.05-p < 0.01). Although, triglyceride (TG), phosphorus, lactate dehydrogenase (LDH), prothrombin time (PT), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) were significantly increased after treatment with carvacrol 1 mg/kg/day (p < 0.05-p < 0.001), all post-treatment measured parameters were within normal range. Treatment with carvacrol 2 mg/kg/day for one month increased FEV1 (p < 0.05). Nevertheless, there was no significant difference in measured variables except LDH, MCH, MCHC, and MCV (p < 0.05-p < 0.01), between the two groups. The results of this phase I study regarding carvacrol effects on healthy subjects, showed clinical safety and tolerability for this agent.

TRPV3 enhances skin keratinocyte proliferation through EGFR-dependent signaling pathways.

Transient receptor potential vanilloid 3 (TRPV3) is highly expressed in skin keratinocytes where it forms Ca2+-permeable nonselective cation channels to regulate various cutaneous functions. TRPV3 expression is upregulated in many skin disorders. Here, we examined how TRPV3 affects keratinocyte proliferation and investigated the underlying mechanism. Topical application of TRPV3 agonist, carvacrol, increased skin thickness in wild type (WT) mice but not in TRPV3 knockout (KO) mice. Carvacrol promoted proliferation of human keratinocytes HaCaT cells at concentrations ≤ 100 µM, but at 300 µM, it decreased cell viability, suggesting a nonmonotonic proliferative effect. Suppression of TRPV3 expression abolished carvacrol-induced cell proliferation while overexpression of TRPV3 enhanced HaCaT cell proliferation. Carvacrol also stimulated Ca2+ influx and proliferation of primary keratinocytes prepared from WT but not TRPV3 KO mice, suggesting that carvacrol-stimulated cell proliferation was dependent on TRPV3-mediated Ca2+ influx. Mechanistic investigation demonstrated that carvacrol stimulated TGFα release and increased phosphorylation levels of EGFR, PI3K, and NF-κB, effects abolished by suppression of TRPV3 expression and CaMKII inhibition. Moreover, inhibition of CaMKII, EGFR, PI3K, or NF-κB diminished carvacrol-induced cell proliferation. We conclude that while strong activation of TRPV3 may cause cell death, moderate activation of TRPV3 promotes cell proliferation in keratinocytes through Ca2+/CaMKII→TGFα/EGFR→PI3K→NF-κB signaling. Graphical abstract Headlights 1. Carvacrol induces epidermal hyperplasia and keratinocyte proliferation. 2. TRPV3 mediates carvacrol-induced epidermal hyperplasia and keratinocyte proliferation. 3. TRPV3 acts through Ca2+/CaMKII→TGFα/EGFR→PI3K→NF-κB signaling to promote keratinocyte proliferation.

The Transient Receptor Potential Melastatin 7 (TRPM7) Inhibitors Suppress Seizure-Induced Neuron Death by Inhibiting Zinc Neurotoxicity.

Transient receptor potential melastatin 7 (TRPM7) is an ion channel that mediates monovalent cations out of cells, as well as the entry of divalent cations, such as zinc, magnesium, and calcium, into the cell. It has been reported that inhibitors of TRPM7 are neuroprotective in various neurological diseases. Previous studies in our lab suggested that seizure-induced neuronal death may be caused by the excessive release of vesicular zinc and the subsequent accumulation of zinc in the neurons. However, no studies have evaluated the effects of carvacrol and 2-aminoethoxydiphenyl borate (2-APB), both inhibitors of TRPM7, on the accumulation of intracellular zinc in dying neurons following seizure. Here, we investigated the therapeutic efficacy of carvacrol and 2-APB against pilocarpine-induced seizure. Carvacrol (50 mg/kg) was injected once per day for 3 or 7 days after seizure. 2-APB (2 mg/kg) was also injected once per day for 3 days after seizure. We found that inhibitors of TRPM7 reduced seizure-induced TRPM7 overexpression, intracellular zinc accumulation, and reactive oxygen species production. Moreover, there was a suppression of oxidative stress, glial activation, and the blood-brain barrier breakdown. In addition, inhibitors of TRPM7 remarkably decreased apoptotic neuron death following seizure. Taken together, the present study demonstrates that TRPM7-mediated zinc translocation is involved in neuron death after seizure. The present study suggests that inhibitors of TRPM7 may have high therapeutic potential to reduce seizure-induced neuron death.

Cuminaldehyde induces oxidative stress-mediated physical damage and death of Haemonchus contortus.

Cuminaldehyde (CA), a monoterpenoid, preset in many plant sources including cumin, induces reactive oxygen-related damage and death in Haemonchus contortus, a parasitic worm with an LD50, values of 127.3 ±â€¯7.5, 184.5 ±â€¯12.1 and 104.1 ±â€¯7.9 µg/mL for an adult female, adult male worms (12 h) and L3 larvae, respectively (24 h). Fifty percent of inhibition of egg hatching (IC50) was obtained at 142.4 ±â€¯11.4 µg/mL after 48 h of exposure. Scanning electron microscopy revealed physical damage to the anterior and posterior ends, intestinal, ovarian, and esophageal regions of the warms on exposure to ca. The exposure of worms to CA also led to a systemic increase in reactive oxygen species (ROS) within 3 h. The better activity was seen with CA compared to standard antihelminthic drug albendazole (Alb). 74 µg/mL CA showed 2.3 fold more increase of catalase (CAT), 0.61 fold increase of superoxide dismutase (SOD), 3.3 fold increase of glutathione peroxidase (GPx) activity and 17.5 fold increase of glutathione (GSH) activity in comparison with Alb (500 µg/mL) for the same time of exposure (3 h). A firm increase of (2.9 fold) was also observed in nitric oxide synthase (NOS) activity within 12 h of exposure with CA (74 µg/mL) in comparison with Alb. Therefore the preclinical potential of CA is much higher than widely used antihelminthic drug Alb. The results open new opportunities to explore CA as a new active antihelminthic molecule.

Cuminaldehyde potentiates the antimicrobial actions of ciprofloxacin against Staphylococcus aureus and Escherichia coli.

Escherichia coli and Staphylococcus aureus are important agents of urinary tract infections that can often evolve to severe infections. The rise of antibiotic-resistant strains has driven the search for novel therapies to replace the use or act as adjuvants of antibiotics. In this context, plant-derived compounds have been widely investigated. Cuminaldehyde is suggested as the major antimicrobial compound of the cumin seed essential oil. However, this effect is not fully understood. Herein, we investigated the in silico and in vitro activities of cuminaldehyde, as well as its ability to potentiate ciprofloxacin effects against S. aureus and E. coli. In silico analyses were performed by using different computational tools. The PASS online and SwissADME programmes were used for the prediction of biological activities and oral bioavailability of cuminaldehyde. For analysis of the possible toxic effects and the theoretical pharmacokinetic parameters of the compound, the Osiris, SwissADME and PROTOX programmes were used. Estimations of cuminaldehyde gastrointestinal absorption, blood brain barrier permeability and skin permeation by using SwissADME; and drug likeness and score by using Osiris, were also evaluated The in vitro antimicrobial effects of cuminaldehyde were determined by using microdilution, biofilm formation and time-kill assays. In silico analysis indicated that cuminaldehyde may act as an antimicrobial and as a membrane permeability enhancer. It was suggested to be highly absorbable by the gastrointestinal tract and likely to cross the blood brain barrier. Also, irritative and harmful effects were predicted for cuminaldehyde if swallowed at its LD50. Good oral bioavailability and drug score were also found for this compound. Cuminaldehyde presented antimicrobial and anti-biofilm effects against S. aureus and E. coli.. When co-incubated with ciprofloxacin, it enhanced the antibiotic antimicrobial and anti-biofilm actions. We suggest that cuminaldehyde may be useful as an adjuvant therapy to ciprofloxacin in S. aureus and E. coli-induced infections.

Carvacrol loaded nanostructured lipid carriers as a promising parenteral formulation for leishmaniasis treatment.

Leishmaniasis are a group of neglected infectious diseases caused by protozoa of the genus Leishmania with distinct presentations. The available leishmaniasis treatment options are either expensive and/or; cause adverse effects and some are ineffective for resistant Leishmania strains. Therefore, molecules derived from natural products as the monoterpene carvacrol, have attracted interest as promising anti-leishmania agents. However, the therapeutic use of carvacrol is limited due to its low aqueous solubility, rapid oxidation and volatilization. Thus, the development of nanostructured lipid carriers (NLCs) was proposed in the present study as a promising nanotechnology strategy to overcome these limitations and enable the use of carvacrol in leishmaniasis therapy. Carvacrol NLCs were obtained using a warm microemulsion method, and evaluated regarding the influence of lipid matrix and components concentration on the NLCs formation. NLCs were characterized by DSC and XRD as well. In addition, to the in vitro carvacrol release from NLCs, the in vitro cytotoxicity and leishmanicidal activity assays, and the in vivo pharmacokinetics evaluation of free and encapsulated carvacrol were performed. NLCs containing carvacrol were obtained successfully using a warm microemulsion dilution method. The NLCs formulation with the lowest particle size (98.42 ± 0.80 nm), narrowest size distribution (suitable for intravenous administration), and the highest encapsulation efficiency was produced by using beeswax as solid lipid (HLB=9) and 5% of lipids and surfactant. The in vitro release of carvacrol from NLCs was fitted to the Korsmeyer and Peppas, and Weibull models, demonstrating that the release mechanism is probably the Fickian diffusion type. Moreover, carvacrol encapsulation in NLCs provided a lower cytotoxicity in comparison to free carvacrol (p<0.05), increasing its in vitro leishmanicidal efficacy in the amastigote form. Finally, the in vivo pharmacokinetics of carvacrol after IV bolus administration suggests that this phenolic monoterpene undergoes enterohepatic circulation and therefore presented a long half-life (t1/2) and low clearance (Cl). In addition, C0, mean residence time (MRT) and Vdss of encapsulated carvacrol were higher than free carvacrol (p < 0.05), favoring a higher distribution of carvacrol in the target tissues. Thus, it is possible to conclude that the developed NLCs are a promising delivery system for leishmaniasis treatment.

Carvacrol reduces hippocampal cell death and improves learning and memory deficits following lead-induced neurotoxicity via antioxidant activity.

Carvacrol is a monoterpene with neuroprotective effects in several animal models of neurodegeneration, including epilepsy, ischemia, and traumatic neuronal events. In this study, we aimed to examine the effects of carvacrol on neurodegeneration induced by lead acetate in rats. A total of 50 male Wistar rats were divided into five equal groups. The control group received drinking water, while the neurotoxic group was exposed to 500 ppm of lead acetate in drinking water for 40 days. The three remaining groups, which were also exposed to 500 ppm of lead acetate, received carvacrol at doses of 25, 50, and 100 mg/kg orally for 40 days. The Morris water maze test was employed to examine spatial learning and memory. Pathological damage to the hippocampus was determined by Nissl staining. The level of malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT) were detected using biochemical analysis and the free radical scavenging activity as evaluated by the DPPH test. Administration of carvacrol significantly restored learning and memory impairment induced by lead acetate. Moreover, carvacrol ameliorated neurodegeneration, antioxidative capacity, and lipid peroxidation in the hippocampus of rats exposed to lead. The present results provide a rationale for the inhibitory role of carvacrol in the attenuation of lead-induced neurotoxicity.

Transdermal delivery enhancement of carvacrol from Origanum vulgare L. essential oil by microemulsion.

Carvacrol has been reported for analgesic and anti-inflammatory activity by cyclooxygenase inhibition but it could induce gastrointestinal toxicity because of its non-selective inhibition. Therefore, the present study aimed to develop transdermal microemulsion from Origanum vulgare essential oil to deliver carvacrol into and through the skin which would overwhelm the gastrointestinal problems. O. vulgare essential oil was extracted by hydrodistillation and its carvacrol content was determined using high performance liquid chromatography. Pseudoternary phase diagrams were constructed using water dilution method to investigate the suitable microemulsion components. Microemulsions were then characterized for external appearance, particle size, size distribution, zeta potential, electrical conductivity, refractive index, viscosity, transmittance, pH, and stability. Additionally, the irritation property of microemulsions were investigated by hen's egg on the chorioallantoic membrane assay. The release profile, percutaneous absorption, and skin retention were investigated using dialysis bag and Franz diffusion cell, respectively. The interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were investigated using the enzyme-linked immunosorbent assay. The results remarked that carvacrol was a major component of O. vulgare essential oil with high concentration of 83.7%. The most suitable microemulsion (ME 1), composing of 5% w/w O. vulgare essential oil, 25%w/w Tween 60, 25%w/w butylene glycol, and 45%w/w deionized water, had the smallest internal droplet size (179.5 ± 27.9 nm), the narrowest polydispersity index (0.30 ± 0.07), the highest transmittance (93.13 ± 0.04%), and Newtonian flow behavior with low viscosity of 0.30 ± 0.07 Pas. ME 1 could reduce the irritation effect of O. vulgare essential oil since ME 1 (IS = 3.1 ± 0.10) exhibited significantly lower irritation effect than its blank formulation (IS = 4.8 ± 0.02) and O. vulgare oil solution (IS = 5.0 ± 0.01) (p < 0.05). Furthermore, ME 1 sustain released carvacrol from the formulation, remarkedly deliver more carvacrol through the skin layer (2.6 ± 2.2%) and significantly retained carvacrol in the skin layer (2.60 ± 1.25%). Additionally, ME 1 significantly enhanced IL-6 inhibition of O. vulgaris oil and carvacrol (p < 0.05). Therefore, O. vulgaris oil microemulsion was suggested to be used for the transdermal delivery and anti-inflammatory activities enhancement of carvacrol.

Effects of the solid lipid nanoparticle of carvacrol on rodents with lung injury from smoke inhalation.

The aim of this present study was to evaluate the effect of solid lipid nanoparticles (SLN) containing carvacrol over the lung damage of airway smoke inhalation. The study was conducted with 30 rats subjected to smoke inhalation and divided into 5 groups such as, normal control, negative control, oxygen group, SLN alone, and SLN+CARV group. The animals were sacrificed 24 h after the induction of inhalation injury further, the tissues of larynx, trachea, and lungs were collected for the histological, hematological, myeloperoxidase, and malondialdehyde analysis. The obtained results showed that treatment with CARV+SLN minimized the inhalation injury, since it reduced malondialdehyde significantly, when compared to the negative control group and minimized the histological changes which proves the absence of pulmonary emphysema and exudate in laryngeal and tracheal lumen in the CARV+SLN-treated group. Meanwhile, the presence of lesion with chronic characteristics was observed in the negative control and oxygen groups. It is suggested that the SLN containing carvacrol minimized oxidative stress and histological damages generated from smoke inhalation in rodents.

Combination of herbal components (curcumin, carvacrol, thymol, cinnamaldehyde) in broiler chicken feed: Impacts on response parameters, performance, fatty acid profiles, meat quality and control of coccidia and bacteria.

The objective of this study was to determine whether curcumin and a commercial microencapsulated phytogenic supplement containing thymol, cinnamaldehyde and carvacrol in broiler chicken feed would improve health and meat quality (fatty acid profile), as well as to determine the coccidiostatic and bactericidal potential of the additives. The broiler chickens were divided into five groups: NC - negative control feed; PC - positive control; CU - with 50 mg/kg of curcumin, PHY - 100 mg/kg phytogenic; and PHY + CU, a combination of both additives at 50 mg/kg (curcumin) and 100 mg/kg (phytogenic). We observed significantly higher levels of total proteins associated with increased circulating globulins, as well as lower levels of uric acid, cholesterol and triglycerides in the PHY + CU group than in the NC. There were significantly fewer oocysts in birds supplemented with additives in the NC group on day 21; on day 35, the NC, PHY and PHY + CU groups had significantly lower counts than the PC and CU groups; however, at 44 days, the lowest counts were in PC group. The bacterial counts were significantly lower on day 21 in all groups that received additives than those of the control group; however, at 44 days, the bacterial and Escherichia coli counts in these groups were significantly higher than those of the control. Curcumin with or without phytogenic agent improved meat quality, with increased antioxidant levels and reduction of lipid peroxidation. There were significantly lower total saturated fatty acid levels and significantly greater monounsaturated/polyunsaturated fatty acid levels in broilers that consumed additives individually and in combination. The combination of additives significantly increased the crypt/villus ratio, a marker of improved intestinal health and performance. Additives potentiated their individual effects, suggesting they can replace conventional growth promoters without compromising health, intestinal mucosa or meat quality.

Feeding oregano oil and its main component carvacrol does not affect ruminal fermentation, nutrient utilization, methane emissions, milk production, or milk fatty acid composition of dairy cows.

Because of their antimicrobial properties, essential oils and their components have been suggested as alternatives to other antimicrobials (e.g., monensin) that are commonly fed to ruminants to improve nutrient utilization and enhance feed efficiency and milk performance. In this study, we evaluated the potential of oregano oil and its main component (carvacrol) as rumen modifiers. For this purpose, 8 ruminally cannulated lactating dairy cows (92 ± 11 d in milk, 36.5 ± 7.6 kg of milk yield, and 703 ± 74 kg of body weight) were used in a double 4 × 4 Latin square (28-d periods). Cows were fed 1 of the 4 following treatments: (1) control (CTL, no additive); (2) monensin [MON, 24 mg/kg of dry matter (DM)]; (3) oregano oil (ORE, 50 mg/kg of DM); and (4) carvacrol (CAR, 50 mg/kg of DM). Cows were fed (ad libitum intake) a total mixed ration consisting of 60% forages (corn silage and alfalfa silage) and 40% concentrates, on a DM basis. Feeding ORE and CAR had no effect on nutrient total-tract apparent digestibility, N utilization, rumen fermentation (i.e., pH, ammonia, volatile fatty acids), protozoa counts, or milk performance. Feeding MON increased the molar proportion of propionate and tended to increase total-tract apparent digestibility of crude protein. None of the feed additives evaluated affected enteric methane production (491 g/d, 21.1 g/kg of DM intake, 6.14% of gross energy intake on average). Milk fatty acid composition was not changed by ORE or CAR, but MON increased the proportion of trans-10 18:1, an intermediate of ruminal biohydrogenation. Thus, when included at 50 mg/kg of dietary dry matter, neither oregano oil nor carvacrol favorably altered rumen fermentation, improved nutrient utilization or milk performance, or mitigated enteric methane emissions in dairy cows.