Antioxidant activities of major thyme ingredients and lack of (oxidative) DNA damage in V79 Chinese hamster lung fibroblast cells at low levels of carvacrol and thymol

Role of acidic sphingomyelinase in thymol-mediated dendritic cell death

SCOPE

Thymol is a component of several plants with antimicrobial activity. Little is known about the effects of thymol on immune cells of the host. This study addressed the effects of thymol on dendritic cells (DCs), regulators of innate and adaptive immunity.

METHODS AND RESULTS

Immunohistochemistry, Western blotting and fluorescence-activated cell sorting analysis were performed in bone marrow-derived DCs either from wild-type mice or from mice lacking acid sphingomyelinase (ASM⁻/⁻) treated and untreated for 24 h with thymol (2-100 μg/mL). Thymol treatment resulted in activation of ASM, stimulation of ceramide formation, downregulation of anti-apoptotic Bcl-2 and Bcl-xL proteins, activation of caspase 3 and caspase 8, DNA fragmentation as well as cell membrane scrambling. The effects were dependent on the presence of ASM and were lacking in ASM⁻/⁻ mice or in wild-type DCs treated with sphingomyelinase inhibitor amitriptyline.

CONCLUSION

Thymol triggers suicidal DC death, an effect mediated by and requiring activation of ASM.

Antioxidant properties of Thymus vulgaris oil against aflatoxin-induce oxidative stress in male rats

The leafy parts of thyme and its essential oil have been used in foods for the flavor, aroma and preservation and also in folk medicines. The aim of the current study was to determine the components of Thymus vulgaris L essential oil and to evaluate the protective effects of this oil against aflatoxin-induce oxidative stress in rats. Thirty six mature male Sprague-Dawley were divided into six treatment groups and treated for 2 weeks as follows: control group; the groups treated orally with low and high doses of T. vulgaris oil (5 and 7.5 mg/kg b.w.); the group fed AFs-contaminated diet (2.5 mg/kg diet) and the groups fed AFs-contaminated diet and treated orally with the oil at the two tested doses. Blood and tissue samples were collected at the end of treatment period for biochemical study and histological examination. The results indicated that the oil contains Carvarcrol (45 mg/g), Thymol (24.7 mg/g), β-Phellandrene (9.7 mg/g), Linalool (4.1 mg/g), Humuline (3.1 mg/g), α-Phellandrene (2.3 mg/g) and Myrcene (2.1 mg/g). However, α and β-pinene, Myrcene, α-thyjone, Tricyclene, 1, 8-cineole, and β-sabinene were found in lower concentrations. Treatment with AFs alone disturbs lipid profile in serum, decreases Total antioxidant capacity, increase creatinine, uric acid and nitric oxide in serum and lipid peroxidation in liver and kidney accompanied with a sever histological changes in the liver tissues. The oil alone at the two tested doses did not induce any significant changes in the biochemical parameters or the histological picture. The combined treatment showed significant improvements in all tested parameters and histological pictures in the liver tissues. Moreover, this improvement was more pronounced in the group received the high dose of the oil. It could be concluded that the essential oil of T. vulgaris has a potential antioxidant activity and a protective effect against AFs toxicity and this protection was dose dependent.