Carvacrol suppresses the expression of inflammatory marker genes in D-galactosamine-hepatotoxic rats

Nigella sativa L. and its bioactive and nutraceutical components in the management of diabetic peripheral neuropathy

Diabetes-induced hyperglycemia leads to excessive production of oxygen free radicals, inflammatory cytokines, and oxidative stress, which initiates diabetic peripheral neuropathy (DPN). Currently, this condition affects 20% of adults with diabetes. Despite significant advances in the treatment of diabetes, the incidence of its complications, including DPN, is still high. Thus, there is a growing research interest in developing more effective and treatment approaches with less side effects for diabetes and its complications. Nigella sativa L. (NS) has received much research attention as an antioxidant, anti-yperglycemic factor, and anti-inflammatory agent. This natural compound demonstrates its antidiabetic neuropathy effect through various pathways, including the reduction of lipid peroxidation, the enhancement of catalase and superoxide dismutase enzyme activity, and the decrease in inflammatory cytokine levels. The present review focuses on the bioactive and nutraceutical components of black cumin (Nigella sativa L.) and their effects on DPN. In addition, we have also summarized the findings obtained from several experimental and clinical studies regarding the antidiabetic neuropathy effect of NS in animal models and human subjects.

Oral administration of liposome-encapsulated thymol could alleviate the inflammatory parameters in serum and hippocampus in a rat model of Alzheimer's disease

BACKGROUND

Neuroinflammation is closely related to Alzheimer's Disease (AD) pathology, hence supplements with anti-inflammatory property could help attenuate the progression of AD. This study was conducted to evaluate the potential anti-inflammatory effects of liposome encapsulated thymol (LET), administered orally, in prevention of Alzheimer in a rat model by anti-inflammatory mechanisms.

METHODS

The rats were grouped into six groups (n = 10 animals per group), including Control healthy (Con), Alzheimer's disease (AD) model, AD model treated with free thymol in 40 and 80 mg/kg body weight (TH40 and TH80), AD model treated with LET in 40 and 80 mg/kg of body weight (LET40 and LET80). The behavioral response of step through latency (Passive Avoidance Test), concentrations of interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) and cyclooxygenase-2 (COX-2) and brain-derived neurotrophic factor (BDNF) were assessed in serum and hippocampus.

RESULTS

The results showed that significant increase in concentrations of IL-1β (P = 0.001), IL-6 (P = 0.001), TNF-α (P = 0.001) and COX-2 (P = 0.001) in AD group compared with healthy control rats. AD induction significantly reduced step through latency and revealed deficits in passive avoidance performance. The results also showed the treatment with free thymol especially in higher concentrations and also LTE could decrease serum concentrations of IL-1β (P < 0.05), IL-6 (P < 0.05), TNF-α (P < 0.05), and COX-2 (P < 0.05) and increase BDNF (P < 0.05) compared with control Alzheimer rats in hippocampus and serum. There were also significant correlations between serum and hippocampus concentrations of IL-1β (r2 = 0.369, P = 0.001), IL-6 (r2 = 0.386, P = 0.001), TNF-α (r2 = 0.412, P = 0.001), and COX-2 (r2 = 0.357, P = 0.001). It means a closed and positive relation between serum and hippocampus concentrations of IL-1β, IL-6, TNF-α, and COX-2.

CONCLUSIONS

LET demonstrates its ability to attenuate neuroinflammatory reaction in AD model through suppression of IL-1β, IL-6, and TNF-α and COX-2 indicators. Hence, it can ameliorate AD pathogenesis by declining inflammatory reaction.

Silymarin and Inflammation: Food for Thoughts

Inflammation is a vital defense mechanism, creating hostile conditions for pathogens, preventing the spread of tissue infection and repairing damaged tissues in humans and animals. However, when inflammation resolution is delayed or compromised as a result of its misregulation, the process proceeds from the acute phase to chronic inflammation, leading to the development of various chronic illnesses. It is proven that redox balance disturbances and oxidative stress are among major factors inducing NF-κB and leading to over-inflammation. Therefore, the anti-inflammatory properties of various natural antioxidants have been widely tested in various in vitro and in vivo systems. Accumulating evidence indicates that silymarin (SM) and its main constituent silibinin/silybin (SB) have great potential as an anti-inflammation agent. The main anti-inflammatory mechanism of SM/SB action is attributed to the inhibition of TLR4/NF-κB-mediated signaling pathways and the downregulated expression of pro-inflammatory mediators, including TNF-α, IL-1β, IL-6, IL-12, IL-23, CCL4, CXCL10, etc. Of note, in the same model systems, SM/SB was able to upregulate anti-inflammatory cytokines (IL-4, IL-10, IL-13, TGF-β, etc.) and lipid mediators involved in the resolution of inflammation. The inflammatory properties of SM/SB were clearly demonstrated in model systems based on immune (macrophages and monocytes) and non-immune (epithelial, skin, bone, connective tissue and cancer) cells. At the same time, the anti-inflammatory action of SM/SB was confirmed in a number of in vivo models, including toxicity models, nonalcoholic fatty liver disease, ischemia/reperfusion models, stress-induced injuries, ageing and exercising models, wound healing and many other relevant model systems. It seems likely that the anti-inflammatory activities of SM/SB are key elements on the health-promoting properties of these phytochemicals.

Oregano (Origanum vulgare) Essential Oil and Its Constituents Prevent Rat Kidney Tissue Injury and Inflammation Induced by a High Dose of L-Arginine

This study aimed to evaluate the protective action of oregano (Origanum vulgare) essential oil and its monoterpene constituents (thymol and carvacrol) in L-arginine-induced kidney damage by studying inflammatory and tissue damage parameters. The determination of biochemical markers that reflect kidney function, i.e., serum levels of urea and creatinine, tissue levels of neutrophil-gelatinase-associated lipocalin (NGAL), and kidney injury molecule-1 (KIM-1), as well as a panel of oxidative-stress-related and inflammatory biomarkers, was performed. Furthermore, histopathological and immunohistochemical analyses of kidneys obtained from different experimental groups were conducted. Pre-treatment with the investigated compounds prevented an L-arginine-induced increase in serum and tissue kidney damage markers and, additionally, decreased the levels of inflammation-related parameters (TNF-α and nitric oxide concentrations and myeloperoxidase activity). Micromorphological kidney tissue changes correlate with the alterations observed in the biochemical parameters, as well as the expression of CD95 in tubule cells and CD68 in inflammatory infiltrate cells. The present results revealed that oregano essential oil, thymol, and carvacrol exert nephroprotective activity, which could be, to a great extent, associated with their anti-inflammatory, antiradical scavenging, and antiapoptotic action and, above all, due to their ability to lessen the disturbances arising from acute pancreatic damage. Further in-depth studies are needed in order to provide more detailed explanations of the observed activities.

In vivo and In silico evidence of the protective properties of carvacrol against experimentally-induced gastric ulcer: Implication of antioxidant, anti-inflammatory, and antiapoptotic mechanisms

Gastric ulcer is a serious disease that affects millions of individuals worldwide. Alcohol consumption is a major contributor to the disease pathogenesis and ethanol-induced ulcer in rats closely recapitulates the clinical pathology of ulcer. In this study, rats were pretreated with carvacrol (CAR,50 and 100 mg/kg, orally) 1 h before absolute ethanol administration to induce gastric ulcer. CAR prevented ethanol-induced increases in gastric volume and acidity while restored mucin content. The gastro-protective activity of CAR, particularly the higher dose (100 mg/kg), was further supported by histopathological examination, as manifested by reduced gastric lesions. Interestingly, oxidative stress is linked to early stages of ulcer development and progression. In this study, ethanol administration upregulated the levels of ROS-producing enzymes, NADPH oxidase homologs 1 and 4 (Nox1 and Nox4) and lipid peroxides while depleting the antioxidant defense mechanisms, including GSH, Glutathione Peroxidase (GPX) and catalase. Interestingly, these alterations were significantly ameliorated by CAR pretreatment. Additionally, CAR possesses anti-inflammatory and anti-apoptotic activities. Pretreatment with CAR blunted ethanol-induced increases in inflammatory cytokines (NF-κB and TNF-α) and rectified the apoptosis regulator (Bax/Bcl2 ratio) in gastric tissue. Moreover, the docking simulation of CAR illustrated good fitting and interactions with GPX, Nox1 and TNF-α through the formation of hydrogen and hydrophobic (pi-H) bonds with conservative amino acids, thus, further supporting the anti-inflammatory and antioxidant effects underlying the gastroprotective effects of CAR. In conclusion, this study elucidates, using in silico and in vivo models, that the gastroprotective activity of CAR is attributed, at least in part, to its mucin-secretagogue, antioxidative, anti-inflammatory, and anti-apoptotic mechanisms.

The effect of carvacrol on the proinflammatory cytokines, histology, and fertility outcome of cisplatin-related ovarian change in a rat model

OBJECTIVE

In women, agents used in chemotherapy treatment have side effects such as accelerating follicular depletion and early menopause. Thus, cytotoxic treatments may cause various effects ranging from partial damage to the ovary to premature ovarian failure (POI) and infertility. This study aimed to investigate the protective effect of carvacrol on cisplatin (CIS)-induced reproductive toxicity in female rats.

MATERIALS AND METHODS

The animals were divided to four groups; a healthy group (HG), administered only cisplatin 2.5 mg/kg (CIS); cisplatin 2.5 mg/kg + carvacrol mg/kg (CC-50), and cisplatin 2.5 mg/kg + carvacrol 100 mg/kg (CC-100). In this study, the CC-50 and CC-100 groups were injected with carvacrol at 50 and 100 mg/kg intraperitoneally (IP). The CIS and HG groupswere administered normal saline as a solvent in the same way. One hour afterwardthe CC-50 and CC-100 groups were injected with cisplatin at 2.5 mg/kg IP. This procedure was continued once a day for 14 days. At the end of this period, six rats from each group were euthanized with high-dose anaesthesia. Biochemical (oxidant-antioxidant and proinflammatory cytokines) and histopathological examinations were performed on the right ovarian tissue removed from the dead rats. The remaining (n = 6 in each group) animals were kept in the laboratory with mature male rats for two months for breeding. Rats that didn't give birth within two months were considered infertile. A one-way ANOVA test was used for the biochemical analysis, the a Kruskal Wallis test was used for the histopathological analysis.

RESULTS

It has been observed that cisplatine causes oxidative stress and inflammatory damage in the ovarian tissue of animals and ultimately causes infertility due to this oxidative stress. While carvacrol significantly suppressed cisplatin-related oxidative stress in ovarian tissue at the 50 and 100 mg/kg doses, it could suppress proinflammatory cytokine increase only at thecytokine increase only at the 100 mg/kg dose. In addition, carvacrol significantly reduced the development of cisplatin-related infertility (from 0 to 83.3%) at a dose of 100 mg/kg.

CONCLUSION

These findings suggest that carvacrol at high doses can reduce the harmful effects of cisplatin on the ovary and improve ovarian reserve in rats.

Effect of Carvacrol on histological analysis and expression of genes involved in an animal model of multiple sclerosis

BACKGROUND

The most common non-traumatic neurological disease in young- and middle-aged adults is multiple sclerosis (MS), leading to central nervous system (CNS) atrophy and neurological disorders with loss of myelin and axonal degeneration. Due to the inadequate efficiency of common treatments, some natural products with antioxidant properties such as Carvacrol have been considered.

OBJECTIVE

the present study aimed to investigate carvacrol's anti-inflammatory and therapeutic effects on MS symptoms in healthy and experimental autoimmune encephalomyelitis (EAE) induced female Lewis rats.

METHODS

The study was performed in three groups of Lewis rats: control group, EAE model, and EAE treated with carvacrol (carvacrol-treated group). The treatment group received 25 mg/kg of carvacrol intraperitoneally daily. Histologic examination and expression analysis of pro-inflammatory genes (Interleukin-1 and 17 (IL-1 and IL-17), Nuclear Factor Kappa B Cells (NF-κB) and Tumor Necrosis Factor-α (TNF-α)), myelin repair, and also regeneration genes (Myelin basic protein (MBP), Oligodendrocyte Transcription Factor 2 (OLIG2) and Platelet-Derived Growth Factor Receptor α (PDGFR-α)) were carried out. Gene studies, Hematoxylin and Eosin (H&E), and Luxol fast blue stain were performed in the lumbar region of the spinal cord.

RESULTS

The EAE clinical scores in the carvacrol-treated group were lower than in untreated rats (P < 0.001). The expression of two genes, IL-17 and MBP, was confirmed using fluorescence immunohistochemistry (FIHC). A significant decrease was observed in NF-κB and IL-17, and IL-1 gene expression. The MBP and OLIG2 gene expression was increased in the carvacrol-treated group (p < 0.001). In EAE, PDGFR-α expression increased about four times. However, carvacrol administration did not affect PDGFR-α and TNF-α gene expression. In this treatment, H&E staining of spinal cord regions showed a significant decrease in inflammatory cell infiltration. Moreover, immunostaining analysis demonstrated a considerable increase in MBP and a reduction in IL-17 secretion.

CONCLUSION

The results showed that carvacrol administration reduces the entry of inflammatory cells into the CNS by stimulating myelination-related processes employing increasing the expression of genes involved in myelin repair and reducing the expression of inflammatory genes. Our findings confirm that carvacrol improves the clinical and pathological symptoms of EAE through its therapeutic and modification properties as a potential adjunctive therapy and needs to be studied more.

Carvacrol prevents acrylamide-induced oxidative and inflammatory liver damage and dysfunction in rats

Background: Acrylamide causes hepatotoxicity with the effect of oxidative stress and inflammatory processes. Carvacrol is a monoterpenic phenol with antioxidant and anti-inflammatory properties. Aims: To determine the effects of carvacrol on oxidative liver injury induced by acrylamide administration in rats. Methods: Rats were divided into three groups of six animals each: healthy group acrylamide group (ACR), and acrylamide + carvacrol group (TACR). First, carvacrol (50 mg/kg) was administered intraperitoneally to the CACR group. One hour later, acrylamide (20 mg/kg) was given orally to the ACR and CACR groups. This procedure was performed for 30 days, after which the animals were sacrificed. The malondialdehyde (MDA) and total glutathione (tGSH) levels, total oxidant (TOS) and total antioxidant status (TAS), tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1β), and nuclear factor kappa b (NF-κB) were measured in the excised liver tissues. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were determined in blood serum samples. Liver tissues were also examined histopathologically. Results: In the ACR group, malondialdehyde, TOS, ALT, AST levels, and NF-κB, IL-1β, and TNF-α levels were found to be high, and tGSH and total antioxidant status levels were low. In addition, diffuse degenerative changes and necrosis in hepatocytes, and moderate inflammation in the portal region were detected in the liver tissues of the ACR group. While carvacrol prevented the biochemical changes induced by acrylamide, it also alleviated the damage in the histological structure. Conclusion: Carvacrol may be used for liver damage caused by acrylamide.

Thyme Oil and Thymol Counter Doxorubicin-Induced Hepatotoxicity via Modulation of Inflammation, Apoptosis, and Oxidative Stress

Doxorubicin (DOX) is an effective anticancer agent with a wide spectrum of activities. However, it has many adverse effects on various organs especially on the liver. Thymol, one of the major components of thyme oil, has biological properties that include anti-inflammatory and antioxidant activities. Thus, this study was designed to examine thyme oil and thymol for their ability to prevent doxorubicin-induced hepatotoxicity in Wistar rats. Hepatotoxicity was induced by an intraperitoneal injection of doxorubicin, at a dose of 2 mg/kg bw/week, for seven weeks. Doxorubicin-injected rats were supplemented with thyme oil and thymol at doses 250 and 100 mg/kg bw, respectively, four times/week by oral gavage for the same period. Treatment of rats with thyme oil and thymol reversed the high serum activities of AST, ALT, and ALP and total bilirubin, AFP, and CA19.9 levels, caused by doxorubicin. Thyme oil and thymol also reduced the high levels of TNF-α and the decreased levels of both albumin and IL-4. These agents ameliorated doxorubicin-induced elevation in hepatic lipid peroxidation and associated reduction in GSH content and GST and GPx activities. Further, the supplementation with thyme oil and thymol significantly augmented mRNA expression of the level of antiapoptotic protein Bcl-2 and significantly downregulated nuclear and cytoplasmic levels of the hepatic apoptotic mediator p53. Thus, thyme oil and thymol successfully counteracted doxorubicin-induced experimental hepatotoxicity via their anti-inflammatory, antioxidant, and antiapoptotic properties.

Investigating the effects of carvacrol in rats using oxygen-induced retinopathy model

Purpose:

Investigating the effects of intraperitoneal carvacrol administration in rats using the oxygen-induced retinopathy (OIR) model.

Methods:

A total of 28 newborn Sprague Dawley rats were used and the OIR model was created using the 50/10% oxygen model. The study composed of four groups in total. While the OIR model was not used in Group I (control group), it was created for Groups II, III, and IV. About 0.01 mL carvacrol, bevacizumab, or 0.9% NaCl was administered intraperitoneal (IP) to the rats in all groups on postnatal day (PND) 14 as follows: Group I and Group II were administered 0.9% NaCl, Group III was administered bevacizumab, and Group IV was administered carvacrol. On PND 18, rats were sacrificed and their right eyes were enucleated.

Results:

Histopathological and immunohistochemical studies showed that the number of vascular endothelial cells (VECs), vascular endothelial growth factor (VEGF), and tumor necrosis factor-α (TNF-α) decreased similarly in Group III and Group IV compared with Group II. VECs values for Group I, Group II, Group III, and Group IV were measured as 0 ± 0, 26.45 ± 4.57, 7.75 ± 1.98, and 5.78 ± 1.72, respectively, and it differed significantly between groups (P < 0.001). Likewise, VEGF levels were observed as 0.06 ± 0.01, 3.31 ± 0.53, 2.47 ± 0.44, and 2.49 ± 0.52, respectively, and it differed significantly between groups (P < 0.001). TNF-α levels were recorded as 0.06 ± 0.01, 3.58 ± 0.38, 2.46 ± 0.49, and 2.29 ± 0.25, respectively, and it differed significantly between groups (P < 0.001). VECs, VEGF, and TNF-α were similar between Group III and IV (range of P values were 0.486–0.998).

Conclusion:

The study demonstrated that carvacrol significantly reduced retinal pathological angiogenesis, NV, VEC nuclei count, VEGF, and TNF-α levels. Moreover, the observed effects were comparable to those of bevacizumab.

The effects of carvacrol on oxidative stress, inflammation, and liver function indicators in a systemic inflammation model induced by lipopolysaccharide in rats

The effect of carvacrol (CAR) on oxidative stress, inflammation, and liver dysfunction induced by lipopolysaccharide (LPS) was explored. The rats (n=40) were daily injected (2 weeks) by saline as control, LPS (1 mg/kg, i.p.), and 25, 50 or 100 mg/kg CAR (i.p.) before LPS. LPS increased aspartate transaminase (AST: 162±13 U/L), alanine aminotransferase (ALT: 74.6±2.15 U/L), alkaline phosphatase (ALK-P: 811±51 U/L), interlukine-1β (IL-1β: 1254±51 pg/g tissue), malondialdehyde (MDA: 32±1.09 nM/g tissue), and nitric oxide (NO: 224±13.5 nM/g tissue) (P<0.01-P<0.001) while, decreased total protein(4.08±0.38 g/dl), albumin(2.79±0.16 g/dl), thiol (5.16±0.19 μM/g tissue), superoxide dismutase (SOD: 10.57±0.13 U/g tissue), and catalase (CAT: 0.78±0.02 U/g tissue) compared to control (P<0.001). CAR reversed the effects of LPS (P<0.05-P<0.001). In the rats treated by 100 mg/kg CAR, the indicators were as follows: AST: 118±10.1 U/L, ALT: 42.5±4.13 U/L, ALK-P: 597±39.91 U/L, IL-1β: 494±15 pg/g tissue, and NO: 141±5.35 nM/g tissue. Both 50 and 100 mg/kg CAR corrected oxidative stress indicators and in the group treated by 100 mg/kg CAR, they were: MDA: 23.4±0.91 nM/g tissue, thiol: 7.98±0.18 μM/g tissue, SOD: 21±0.8 U/g tissue, and CAT: 1.12±0.02 U/g tissue(P<0.05-P<0.001). In conclusion, CAR improved liver function, accompanied with antioxidant and antiinflammatory effects.

Carvacrol alleviates liver fibrosis by inhibiting TRPM7 and modulating the MAPK signaling pathway

Liver fibrosis is a compensatory response to the tissue repair process. The activation and proliferation of hepatic stellate cells (HSCs) are thought to be related to the occurrence of hepatic fibrosis. Therefore, inhibiting the activation and proliferation of HSCs is a key step in alleviating liver fibrosis. As a non-specific inhibitor of transient receptor potential melastatin 7 (TRPM7), carvacrol has anti-tumor, anti-inflammatory and anti-hepatic fibrosis activities. This study aimed to explore the protective effect of carvacrol on liver fibrosis and related molecular mechanisms. A CCl4-induced liver fibrosis mouse model and platelet-derived growth factor (PDGF-BB)-activated HSC-T6 cells (a rat hepatic stellate cell line) were employed for in vivo and in vitro experiments. C57BL/6J mice were orally administered different concentrations of carvacrol every day for 6 weeks during the development of CCl4-induced liver fibrosis. The results show that carvacrol could effectively reduce liver damage and the progression of liver fibrosis in mice, which are expressed as fibrotic markers levels were reduced and histopathological characteristics were improved. Moreover, carvacrol inhibited the proliferation and activation of HSC-T6 cells induced by PDGF-BB. In addition, it was found that carvacrol inhibits the expression of TRPM7 and mediated through mitogen-activated protein kinases (MAPK). Collectively, our study shows that carvacrol can reduce liver fibrosis by inhibiting the activation and proliferation of hepatic stellate cells, and the MAPK signaling pathway might be involved in this process.

Cardioprotective Efficacy of Silymarin Liquisolid in Isoproterenol Prompted Myocardial Infarction in Rats

Myocardial infarction (MI) is the principal cause of death in many countries. Silymarin (SM) is a herbal antioxidant and can be efficiently used in preventing cardiovascular diseases (CVDs). The study is aimed to enhance the absorption rate and biological activity of SM by using liquisolids besides investigating the cardioprotective activity of SM and its selected liquisolid formula against isoproterenol prompted cardiotoxicity in rats. Eight formulae were prepared according to (2³) full-factorial design. The effect of viscosity increasing agent type and concentration, as well as the carrier/coat ratio on the dissolution rate and angle of repose were studied. All formulae were tested for content uniformity, micromeritic properties, dissolution performance besides the evaluation of its physicochemical properties, and scanning electron microscopy (SEM). Based on the factorial design outcomes, the highest desirability was obtained from F3 with excipient ratio value (R) of 20%, dissolution rate at Q_5 min of 26.9%, and angle of repose of 19. Oral administration of F3 liquisolid and SM revealed a significant protective efficacy against the modification of cardiac plasma markers, brain natriuretic peptide (BNP), interleukin-10 (IL-10), vascular endothelial growth factor (VEGF), and transforming growth factor (TGF)-β1 besides cardiac superoxide dismutase (SOD), malondialdehyde (MDA), and total protein kinase-1 (Akt-1) levels. Additionally, they minimized cardiac inducible nitric oxide synthase (iNOS), microRNA-34a (miR-34a), and p38 mitogen-activated protein kinase (p38-MAPK) levels. In conclusion, F3 liquisolid compact possessed an overall pronounced results over pure SM reckoned to its enhanced solubility and efficacy.

Potential anti-inflammatory and immunomodulatory effects of carvacrol against ovalbumin-induced asthma in rats

BACKGROUND

Asthma is a complex inflammatory disease which affects multiple individuals worldwide especially pediatric ages.

AIMS

This study aimed to assess the possible protective effect of carvacrol, as natural antioxidant anti-inflammatory drug, against bronchial asthma induced experimentally in rats.

MAIN METHODS

Rats were randomly allocated into 5 groups; a normal control group, control drug group received only carvacrol, an asthma control group, a standard treatment group receiving dexamethasone (DEXA) and carvacrol treatment group. Bronchial asthma was induced by sensitization with i.p dose followed by challenge with intranasal dose of ovalbumin (OVA). 24 h after the last challenge, absolute eosinophil count (AEC) were determined in bronchoalveolar lavage fluids (BALF). Immunoglobulin E (IgE) was determined in serum. Inflammatory biomarkers like Interleukin-4 (IL-4), interleukin-5 (IL-5), interleukin 13 (IL-13), tumor necrosis factor-alpha (TNF-α) and interferon-gamma (IFN-γ) were also measured in BALF. Nitrosative stress biomarker namely inducible nitric oxide synthase (iNOS) was determined in BALF as well as oxidative stress biomarkers namely superoxide dismutase (SOD), glutathione (GSH) and malondialdehyde (MDA) were determined in lung tissue. Additionally, histopathological study, immunohistochemical study of UCN and western blot analysis of SP-D were performed.

KEY FINDINGS

Carvacrol administration significantly reduced the values of AEC, IgE, IL-4, IL-5, IL-13, TNF-α, IFN-γ, iNOS and MDA, while it significantly increased the values of SOD and GSH as compared to the asthmatic group. Histopathological, immunohistochemical and western blot study reinforced the biochemical results.

SIGNIFICANCE

Carvacrol may be a promising protective agent against bronchial asthma induced experimentally in rats.

Antiproliferative and Anti-invasion Effects of Carvacrol on PC3 Human Prostate Cancer Cells through Reducing pSTAT3, pAKT, and pERK1/2 Signaling Proteins

BACKGROUND

One of the most effective parameters in the progression of the prostate cancer is interleukin (IL)-6 through affecting pSTAT3, pERK1/2, and pAKT cell signaling proteins. Carvacrol is an herbal antioxidant with antitumor effects. The purpose of this study was to investigate the effects of carvacrol on IL-6 gene expression, pSTAT3, pAKT, pERK1/2 cellular signaling proteins, and invasion in human prostate cancer PC3 cells.

METHODS

PC3 cell viability was evaluated by MTT assay with different concentrations of carvacrol (0-800 μM). IL-6 gene expression and cellular concentration of pSTAT3, pERK1/2, and pAKT were investigated using the real-time reverse transcription quantitative polymerase chain reaction (RT-qPCR) and western blotting technic, respectively. PC3 cell invasion was determined by invasion assay test.

RESULTS

Carvacrol IC50 for PC3 prostate cancer cells was 360 μM. Carvacrol led to a significant reduction (P < 0.05) for IL-6 gene expression in a dose-dependent manner compared to control. IL-6 protein reduced 41.5% and 52.7% when compared with control cells at 360 and 420 μM of carvacrol, respectively. Carvacrol led to a decline in pSTAT3, pAKT, and pERK1/2 above 360 μM compared to control. PC3 potential invasion was significantly reduced after treatment with carvacrol in a dose-dependent manner.

CONCLUSIONS

Decreased IL-6 protein level by carvacrol resulted in diminishing of pSTAT3, pERK1/2, and pAKT signaling proteins, which leads to the reduction of the cell survival, proliferation, and invasion in PC3 cells.

Carvacrol Downregulates Lysyl Oxidase Expression and Ameliorates Oxidative Stress in the Liver of Rats with Carbon Tetrachloride-Induced Liver Fibrosis

In the current study, we aimed to investigate the effect of carvacrol on the suppression of liver fibrosis progression through targeting lysyl oxidase (LOX) expression. The rats received carbon tetrachloride (CCl₄) intraperitoneally and carvacrol orally for 10 weeks. Liver damage was evaluated by measuring the serum level of alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase and hepatic oxidative stress parameters including total antioxidant capacity, total thiol group and total oxidant status spectrophotometry and malondialdehyde fluorometrically. Extracellular deposition of collagen was detected using Masson's trichrome standing. Furthermore the gene expression of lysyl oxidase homolog 2 (Loxl2) was analyzed using quantitative reverse transcription-polymerase chain reaction. And then the protein level of LOX was detected in liver tissue by western blot method. Carvacrol administration normalized serum biochemical parameters and improved oxidative stress status in liver homogenate of CCl₄ treated rats. Collagen fiber bundles in interlobular spaces were decreased remarkably by carvacrol treatment. Also, carvacrol downregulated hepatic gene expression of Loxl2 and protein level of LOX. Our data clearly revealed that carvacrol suppresses progression of liver fibrosis development via attenuating of liver damage and oxidative stress status as well as via downregulation of hepatic gene expression of Loxl2 and protein level of LOX.

Carvacrol and Thymol Modulate the Cross-Talk between TNF-α and IGF-1 Signaling in Radiotherapy-Induced Ovarian Failure

Premature ovarian failure (POF) is a common cause of infertility in premenopausal women who are unavoidably exposed to cytotoxic therapy. Radiotherapy is one of the most effective cytotoxic treatments. However, the radiosensitivity of ovarian tissues limits its therapeutic outcome and results in the depletion of the primordial follicle and loss of fertility. Therefore, the need for an effective radioprotective therapy is evident especially when none of the current clinically used modalities for radioprotection succeeds efficiently. The present study investigated the potential radioprotective effect of carvacrol (CAR) (80 mg) or thymol (80 mg) on gamma- (γ-) irradiation-induced ovarian damage as well as their role in the cross-talk between IGF-1 and TNF-α signaling and antioxidative activity. In immature female Wister rats, a single dose of whole-body irradiation (3.2 Gy, LD₂₀) produced considerable ovarian damage, which was evident by histopathological findings and hormonal changes. Interestingly, pretreatment with CAR or thymol significantly enhanced the follicular development and restored the anti-Mullerian hormone (AMH), E2, and FSH levels. Both essential oils improved the irradiation-mediated oxidative stress and reduction in proliferating cell nuclear antigen (PCNA) expression. Moreover, irradiated rats exhibited an inverse relationship between IGF-1 and TNF-α levels two days post irradiation, which was further inverted by the pretreatment with CAR and thymol and ought to contribute in their radioprotective mechanisms. In conclusion, CAR and thymol showed a radioprotective effect and rescued the ovarian reserve mainly through counteracting oxidative stress and the dysregulated cross-talk between IGF-1 and TNF-α.

Effects of Carvacrol in an Experimentally Induced Esophageal Burn Model: Expression of VEGF and Caspase-3 Proteins

INTRODUCTION

We investigated the therapeutic effects of carvacrol in an experimental esophageal burn rat model with immunohistochemical techniques. Materials and Methods: Three groups were included in this study, composed of eight Wistar albino rats each. The control group was given 1 mL 0.9% (wt/vol) NaCl; esophageal burns were induced in groups 2 and 3 by administration of 1 mL 40% NaOH in the distal 2 cm of the esophagus. The treatment group was administered 75 mg/kg carvacrol in 2 mL 0.9% NaCl for 10 days. After a routine histological examination of the tissues, sections were stained with vascular endothelial growth factor (VEGF) and caspase-3 for immunohistochemical analysis and were examined under a light microscope. Results: In the control group, there were regular cells in the cornified epithelial tissue and cylindrical cells in the basal layer, which faced toward the apical surface in the mitotic phase. The burn group displayed wide degeneration, necrosis, and abundant apoptotic cells in the epithelial tissue as well as intense inflammatory cell infiltration. In the treatment group, there was an increase in mitotic activity in the basal cells of the epithelial layer and degenerative changes, but a preserved epithelial layer and significant cornified structures. The treatment group showed positive caspase-3 expression in some apoptotic cells within the epithelial layer and in connective tissue, and there were only a small number of degenerated cells in the muscle layer. Additionally, in the treatment group, VEGF expression was evident in small numbers of inflammatory cells in the papillary region of the epithelium, and in dilated vascular endothelial cells. Conclusions: Carvacrol may contribute to a reduction in fibrosis by decreasing inflammation and preventing cell apoptosis.

Inhibitory effects of scoparone from chestnut inner shell on platelet-derived growth factor-BB-induced vascular smooth muscle cell migration and vascular neointima hyperplasia

BACKGROUND

Compounds of the inner shell of chestnut (Castanea crenata) have diverse biological activities, including anti-cancer and anti-oxidant activities. Here we explored the effects of an extract of chestnut inner shells and of its bioactive component scoparone on vascular smooth muscle cell migration and vessel damage.

RESULTS

The ethanol extract of chestnut inner shells, containing 11 major compounds, inhibited platelet-derived growth factor (PDGF)-BB-induced migration of rat aortic smooth muscle cells (RASMCs). Among these compounds, scoparone (6,7-dimethoxycoumarin) suppressed RASMC migration and wound healing in response to PDGF-BB but did not affect RASMC proliferation. In RASMCs, scoparone inhibited the PDGF-BB-induced rat aortic sprout outgrowth and attenuated the PDGF-BB-mediated increase in phosphorylation of mitogen-activated protein kinases (MAPKs), p38 MAPK and extracellular signal-regulated kinase 1/2. The in vivo administration of scoparone resulted in the attenuation of neointima formation in balloon-injured carotid arteries of rats.

CONCLUSION

These findings demonstrate that scoparone, found in chestnut inner shells, may inhibit cell migration through suppression of the phosphorylation of MAPKs in PDGF-BB-treated RASMCs, probably contributing to the reduction of neointimal hyperplasia induced after vascular injury. Therefore, scoparone and chestnut inner shell may be a potential agent or functional food, respectively, for the prevention of vascular disorders such as vascular restenosis or atherosclerosis. © 2019 Society of Chemical Industry.

Carvacrol mitigates proconvulsive effects of lipopolysaccharide, possibly through the hippocampal cyclooxygenase-2 inhibition

Systemic injection of LPS changes neuronal excitability and increase susceptibility for convulsions. Carvacrol exerts neuroprotective and antiepileptic effects in animal models. Herein, we investigated the anticonvulsive effect of carvacrol on LPS induced seizure severity and possible involvement of the hippocampal COX-1 and -2 activities in this effect. Adult male wistar rats were used. LPS was injected (400 μg/kg; i.p.) four hours before the PTZ (80 mg/kg; i.p.) injection. Carvacrol was injected (100 mg/kg; i.p.) immediately after the LPS injection. Following the PTZ injection, behavioral seizures were observed for 30 min. Latency and duration for each stage were recorded for analysis. Rats divided into seven groups: (1) PTZ, (2) LPS + PTZ, (3) carvacrol + PTZ, (4) LPS + carvacrol + PTZ, (5) LPS, (6) carvacrol, (7) intact. At the end of the experimental procedure the hippocampus of all animals were extracted to measure COX- 1 and 2 levels using the ELISA. LPS injection four hours before the PTZ injection were significantly reduced latency to seizure stages 3-5 and increased duration of the stage 5 in compare with PTZ group (p < 0.05). Carvacrol significantly reduced these effects of LPS on seizure susceptibility (p < 0.05). However, injection of carvacrol alone before the PTZ injection did not significantly affect seizure indexes in compare with PTZ group. Additionally, LPS significantly increased hippocampal level COX-2 but not COX-1 (p < 0.01) and carvacrol significantly attenuates this effect of LPS (p < 0.001). Carvacrol prevents the proconvulsant effect of LPS possibly through the inhibition of the COX-2 increased activity.

Beneficial effects of Thymus vulgaris extract in experimental autoimmune encephalomyelitis: Clinical, histological and cytokine alterations

The imbalance between pro and anti-inflammatory cytokines plays an important role in the pathogenesis of multiple sclerosis (MS) and its animal model, experimental autoimmune encephalomyelitis (EAE). Thymus vulgaris (thyme) as a traditional medicinal plant has been reported to exert antimicrobial, antioxidant, and anti-inflammatory effects. Therefore, this study evaluated the modulatory effects of Thymus vulgaris on the clinical symptoms, histopathological scores, and the production of some anti-inflammatory (TGF-β, IL-4, and IL-10) and pro-inflammatory (IFN-γ, IL-6 and IL-17) cytokines in EAE model. EAE was induced by MOG35-55 peptide and mice were treated intra-peritoneally (i.p) with phosphate buffered saline (PBS) in the control group or thyme extract (50 or 100 mg/kg of body weight, every other day) in thyme-treated EAE groups, from day 0 to +21 of post MOG immunization. Mice were sacrificed at day 22, and splenocytes were isolated and re-stimulated in vitro with MOG in order to measure the cytokine production and proliferation of re-stimulated cells by enzyme linked immunosorbent assay (ELISA) method and WST-1 reagent, respectively. The clinical symptoms and histopathological scores of the CNS were lower in thyme-treated than EAE control group. Furthermore, the production of IFN-γ and IL-6 by splenocytes was lower in thyme-treated EAE than in the control group. The production of IL-10 and TGF-β increased in mice treated with thyme extract compared to the control group. In this study, we showed for the first time that the immunomodulatory effects of Thymus vulgaris in EAE model. Thus, the possible therapeutic potential of thyme for treatment of MS could be considered in future research.

Monoterpenes modulating cytokines - A review

Inflammatory response can be driven by cytokine production and is a pivotal target in the management of inflammatory diseases. Monoterpenes have shown that promising profile as agents which reduce the inflammatory process and also modulate the key chemical mediators of inflammation, such as pro and anti-inflammatory cytokines. The main interest focused on monoterpenes were to develop the analgesic and anti-inflammatory drugs. In this review, we summarized current knowledge on monoterpenes that produce anti-inflammatory effects by modulating the release of cytokines, as well as suggesting that which monoterpenoid molecules may be most effective in the treatment of inflammatory disease. Several different inflammatory markers were evaluated as a target of monoterpenes. The proinflammatory and anti-inflammatory cytokines were found TNF-α, IL-1β, IL-2, IL-5, IL-4, IL-6, IL-8, IL-10, IL-12 IL-13, IL-17A, IFNγ, TGF-β1 and IFN-γ. Our review found evidence that NF-κB and MAPK signaling are important pathways for the anti-inflammatory action of monoterpenes. We found 24 monoterpenes that modulate the production of cytokines, which appears to be the major pharmacological mechanism these compounds possess in relation to the attenuation of inflammatory response. Despite the compelling evidence supporting the anti-inflammatory effect of monoterpenes, further studies are necessary to fully explore their potential as anti-inflammatory compounds.

Carvacrol ameliorates haematological parameters, oxidant/antioxidant biomarkers and pulmonary function tests in patients with sulphur mustard-induced lung disorders: A randomized double-blind clinical trial

WHAT IS KNOWN AND OBJECTIVE

In this study, the effect of carvacrol (CAR) on pulmonary function tests (PFT), haematological indices and oxidant/antioxidant biomarkers in patients with sulphur mustard (SM)-induced lung disorders was examined.

METHODS

Twenty patients exposed to SM 27-30 years ago were divided into two groups and treated with either placebo (P) or CAR (1.2 mg/kg per day) (n = 10 for each group). Forced vital capacity (FVC), peak expiratory flow (PEF), total and different white blood cell (WBC), haematological parameters and oxidant/antioxidant biomarkers were measured at the baseline (step 0), one and two months (steps I and II, respectively) after starting the treatment.

RESULTS AND DISCUSSION

PEF was significantly increased in the CAR-treated group in step II compared to step 0 (P < .01). Total WBC (P < .01) and neutrophil (P < .05) count in the CAR-treated group were significantly decreased in the group in steps I and II (P < .01 for both cases) compared to step 0. The levels of thiol, superoxide dismutase and catalase in the CAR-treated group were significantly increased (P < .05 to P < .001) in steps I and II, but malondialdehyde significantly decreased in step II compared to step 0 (P < .01). The percentage of total and differential WBC, oxidant/antioxidant biomarkers, FVC and PEF values following a two-month treatment period were significantly improved in the CAR-treated group compared to the placebo group (P < .05 to P < .001).

WHAT IS NEW AND CONCLUSION

Two-month treatment with CAR reduced inflammatory cells and oxidant biomarkers, whereas increased antioxidant biomarkers and improved PFT tests in SM-exposed patients.

Carvacrol ameliorates inflammatory response in interleukin 1β-stimulated human chondrocytes

Carvacrol, a monoterpenic phenol present in Origanum vulgare (oregano) and Thymus vulgaris (thyme), possesses anti‑inflammatory effects; however, little is known about the effects and underlying mechanism of carvacrol on chondrocytes in osteoarthritis (OA). The present study aimed to investigate the protective effects of carvacrol against inflammation in interleukin 1β (IL‑1β)‑stimulated human chondrocytes. The results indicated that carvacrol inhibited nitric oxide (NO) and prostaglandin E2 (PGE2) production, and decreased the expression of inducible NO synthase (iNOS) and cyclooxygenase (COX‑2). Carvacrol also suppressed the protein expression levels of matrix metalloproteinase (MMP)‑3 and MMP‑13 in IL‑1β‑stimulated human OA chondrocytes. Furthermore, carvacrol suppressed the activation of nuclear factor (NF)‑κB signaling pathway in IL‑1β‑induced human chondrocytes. In conclusion, the present results demonstrated that carvacrol was able to inhibit IL‑1β‑induced NO and PGE2 production, as well as iNOS, COX‑2 and MMPs expression in human chondrocytes by suppressing the activation of NF‑κB signaling pathway. Thus, carvacrol may have potential therapeutic functions for the treatment of OA.

Protective Effects of the Third Generation Vasodilatory Βeta - Blocker Nebivolol against D-Galactosamine - Induced Hepatorenal Syndrome in Rats

BACKGROUND:

Renal dysfunction is very common in patients with advanced liver cirrhosis and portal hypertension. The development of renal failure in the absence of clinical, anatomical or pathological causes renal of failure is termed hepatorenal syndrome (HRS).

AIM:

The present study was constructed to investigate the possible protective effects of nebivolol (Nebi) against D-galactosamine (Gal)-induced HRS in rats.

MATERIAL AND METHODS:

Rats were treated with Nebi for ten successive days. On the 8th day of the experiment, they received a single dose of Gal. Serum levels of Cr, BUN, Na+ and K+ as well as AST, ALT, total bilirubin (TB), NH3 and endothelin-1 (ET-1) were determined following Gal administration. Moreover, renal and liver contents of MDA, GSH, F2-isoprostanes (F2-IPs), tumor necrosis factor-alpha (TNF-α), nuclear factor kappa-B (NF-κB), total nitric oxide (NO), in addition to activities of caspase-3 (Cas-3), heme oxygenase-1 (HO-1), inducible and endothelial NO synthase (iNOS and eNOS) enzymes were also assessed. Finally, histopathological examination was performed.

RESULTS:

Nebi attenuated Gal-induced renal and hepatic dysfunction. It also decreased the Gal-induced oxidative stress and inflammatory recruitment.

CONCLUSION:

Results demonstrated both nephroprotective and hepatoprotective effects of Nebi against HRS and suggested a role of its antioxidant, anti-inflammatory, anti-apoptotic and NO-releasing properties.

Lippia origanoides extract induces cell cycle arrest and apoptosis and suppresses NF-κB signaling in triple-negative breast cancer cells

Treatments targeting hormone receptors typically fail to provide a positive clinical outcome against triple-negative breast cancers (TNBC), which lack expression of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (Her2/neu). Towards identifying viable treatments for aggressive breast cancer, we have tested an extract of the tropical plant Lippia origanoides (LOE) on TNBC and normal cells lines to uncover its potential anticancer effects. Treatment with LOE reduced TNBC cell viability in a dose-dependent manner to a greater extent than in normal mammary epithelial MCF10A cells. In MDA-MB-231 cells, LOE was found to halt the cell cycle in the G0/G1 phase via cyclin D1 and cIAP2 regulation, and induce apoptosis without promoting necrosis via caspase-8/-3 and PARP cleavage. Constitutive nuclear factor-κB (NF-κB) signaling has been shown to contribute to the heightened inflammatory state and survival in TNBC cells. Herein, we also provide evidence that LOE inhibits NF-κB signaling by reducing RIP1 protein levels in MDA-MB-231 cells. These studies reveal that LOE suppresses key features of the progression of aggressive breast cancer cells and provides a basis for further definition of its underlying mechanisms of action and anticancer potential.

The protective effects of carvacrol and thymol against paracetamol-induced toxicity on human hepatocellular carcinoma cell lines (HepG2)

Acetaminophen (APAP) overdose could induce liver damage and lead to acute liver failure. The treatment of APAP overdoses could be improved by new therapeutic strategies. Thymus spp., which has many beneficial effects and has been used in folk medicine, is one such potential strategy. In the present study, the hepatoprotective activity of the main constituents of Thymus spp., carvacrol and thymol, were evaluated in light of APAP-induced hepatotoxicity. We hoped to understand the hepatoprotective mechanism of these agents on the antioxidant system and pro-inflammatory cytokines in vitro. Dose-dependent effects of thymol and carvacrol (25, 50, and 100 µM) were tested on cultured HepG2 cells. N-Acetylcysteine (NAC) was tested as positive control. We showed that APAP inhibited HepG2 cell growth by inducing inflammation and oxidative stress. Incubating APAP-exposed HepG2 cells with carvacrol and thymol for 24 h ameliorated this inflammation and oxidative stress. We also evaluated alanine transaminase and lactate dehydrogenase levels of HepG2 cells. We found that thymol and carvacrol protected against APAP-induced toxicity in HepG2 cells by increasing antioxidant activity and reducing pro-inflammatory cytokines, such as tumor necrosis factor α and interleukin 1β. Taking together high-dose thymol and carvacrol treatment has an effect close to NAC treatment in APAP toxicity, but thymol has better treatment effect than carvacrol.

Silymarin as a Natural Antioxidant: An Overview of the Current Evidence and Perspectives

Silymarin (SM), an extract from the Silybum marianum (milk thistle) plant containing various flavonolignans (with silybin being the major one), has received a tremendous amount of attention over the last decade as a herbal remedy for liver treatment. In many cases, the antioxidant properties of SM are considered to be responsible for its protective actions. Possible antioxidant mechanisms of SM are evaluated in this review. (1) Direct scavenging free radicals and chelating free Fe and Cu are mainly effective in the gut. (2) Preventing free radical formation by inhibiting specific ROS-producing enzymes, or improving an integrity of mitochondria in stress conditions, are of great importance. (3) Maintaining an optimal redox balance in the cell by activating a range of antioxidant enzymes and non-enzymatic antioxidants, mainly via Nrf2 activation is probably the main driving force of antioxidant (AO)  action of SM. (4) Decreasing inflammatory responses by inhibiting NF-κB pathways is an emerging mechanism of SM protective effects in liver toxicity and various liver diseases. (5) Activating vitagenes, responsible for synthesis of protective molecules, including heat shock proteins (HSPs), thioredoxin and sirtuins and providing additional protection in stress conditions deserves more attention. (6) Affecting the microenvironment of the gut, including SM-bacteria interactions, awaits future investigations. (7) In animal nutrition and disease prevention strategy, SM alone, or in combination with other hepatho-active compounds (carnitine, betaine, vitamin B₁₂, etc.), might have similar hepatoprotective effects as described in human nutrition.

Chemistry and multibeneficial bioactivities of carvacrol (4-isopropyl-2-methylphenol), a component of essential oils produced by aromatic plants and spices

Aromatic plants produce organic compounds that may be involved in the defense of plants against phytopathogenic insects, bacteria, fungi, and viruses. One of these compounds, called carvacrol, which is found in high concentrations in essential oils such as oregano, has been reported to exhibit numerous bioactivities in cells and animals. This integrated overview surveys and interprets our present knowledge of the chemistry and analysis of carvacrol and its beneficial bioactivities. These activities include its antioxidative properties in food (e.g., lard, sunflower oil) and in vivo and the inhibition of foodborne and human antibiotic-susceptible and antibiotic-resistant pathogenic bacteria, viruses, pathogenic fungi and parasites, and insects in vitro and in human foods (e.g., apple juice, eggs, leafy greens, meat and poultry products, milk, oysters) and food animal feeds and wastes. Also covered are inhibitions of microbial and fungal toxin production and the anti-inflammatory, analgesic, antiarthritic, antiallergic, anticarcinogenic, antidiabetic, cardioprotective, gastroprotective, hepatoprotective, and neuroprotective properties of carvacrol as well as metabolic, synergistic, and mechanistic aspects. Areas for future research are also suggested. The collated information and suggested research might contribute to a better understanding of agronomical, biosynthetic, chemical, physiological, and cellular mechanisms of the described health-promoting effects of carvacrol, and facilitate and guide further studies needed to optimize the use of carvacrol as a multifunctional food in pure and encapsulated forms, in edible antimicrobial films, and in combination with plant-derived and medical antibiotics to help prevent or treat animal and human diseases.

Assessment of antioxidative, chelating, and DNA-protective effects of selected essential oil components (eugenol, carvacrol, thymol, borneol, eucalyptol) of plants and intact Rosmarinus officinalis oil

Selected components of plant essential oils and intact Rosmarinus officinalis oil (RO) were investigated for their antioxidant, iron-chelating, and DNA-protective effects. Antioxidant activities were assessed using four different techniques. DNA-protective effects on human hepatoma HepG2 cells and plasmid DNA were evaluated with the help of the comet assay and the DNA topology test, respectively. It was observed that whereas eugenol, carvacrol, and thymol showed high antioxidative effectiveness in all assays used, RO manifested only antiradical effect and borneol and eucalyptol did not express antioxidant activity at all. DNA-protective ability against hydrogen peroxide (H2O2)-induced DNA lesions was manifested by two antioxidants (carvacrol and thymol) and two compounds that do not show antioxidant effects (RO and borneol). Borneol was able to preserve not only DNA of HepG2 cells but also plasmid DNA against Fe(2+)-induced damage. This paper evaluates the results in the light of experiences of other scientists.

Anti-oxidative and anti-inflammatory effects of Tagetes minuta essential oil in activated macrophages

OBJECTIVE

To investigate antioxidant and anti-inflammatory effects of Tagetes minuta (T. minuta) essential oil.

METHODS

In the present study T. minuta essential oil was obtained from leaves of T. minuta via hydro-distillation and then was analyzed by gas chromatography-mass spectrometry. The anti-oxidant capacity of T. minuta essential oil was examined by measuring reactive oxygen, reactive nitrogen species and hydrogen peroxide scavenging. The anti-inflammatory activity of T. minuta essential oil was determined through measuring NADH oxidase, inducible nitric oxide synthase and TNF-α mRNA expression in lipopolysacharide-stimulated murine macrophages using real-time PCR.

RESULTS

Gas chromatography-mass spectrometry analysis indicated that the main components in the T. minuta essential oil were dihydrotagetone (33.86%), E-ocimene (19.92%), tagetone (16.15%), cis-β-ocimene (7.94%), Z-ocimene (5.27%), limonene (3.1%) and epoxyocimene (2.03%). The T. minuta essential oil had the ability to scavenge all reactive oxygen/reactive nitrogen species radicals with IC50 12-15 µg/mL, which indicated a potent radical scavenging activity. In addition, T. minuta essential oil significantly reduced NADH oxidase, inducible nitric oxide synthaseand TNF-α mRNA expression in the cells at concentrations of 50 µg/mL, indicating a capacity of this product to potentially modulate/diminish immune responses.

CONCLUSIONS

T. minuta essential oil has radical scavenging and anti-inflammatory activities and could potentially be used as a safe effective source of natural anti-oxidants in therapy against oxidative damage and stress associated with some inflammatory conditions.