Date seed oil inhibits hydrogen peroxide-induced oxidative stress in human epidermal keratinocytes.

BACKGROUND: Oxidative stress has been implicated in various skin diseases through the generation of reactive oxygen species and the depletion of endogenous antioxidant systems. The administration of antioxidants is reportedly helpful, notably to enhance the healing process. To protect the skin against oxidative damages, we have studied the effect of new oil: "date seed oil" (DSO). This oil, may serve as a potential source of natural antioxidants such as phenols and tocopherols. METHODS: Here, we report the protective effect of DSO against hydrogen peroxide (H(2)O(2))-induced oxidative stress in terms of lipid peroxidation, depletion of endogenous antioxidant defense enzymes such as superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) using normal human epidermal keratinocytes (NHEK). RESULTS: In the investigated model system, DSO has significant chemoprotective effect, by inhibition of damage caused by H(2)O(2) compared with cells without such addition endowing with a radical scavenging ability. Treatment of NHEK with DSO inhibited H(2)O(2)-induced lipid peroxidation. In addition, this oil inhibited H(2)O(2)-induced depletion of antioxidant defense components, such as SOD, CAT and GPx. CONCLUSIONS: Our findings demonstrate that DSO is an efficient extract that is able to prevent keratinocytes oxidative damage induced by H(2)O(2) exposure and may thus be a potential promising candidate, as a chemopreventive agent, in the development of keratinocytes-related pathologies.

Sperm quality improvement after date seed oil in vitro supplementation in spontaneous and induced oxidative stress.

In vitro supplementation with date seed oil (DSO) can protect spermatozoa against hydrogen peroxide (H2O2)-mediated damage and can improve sperm function, possibly owing to antioxidant properties. We tested the antioxidant effects of DSO on human sperm motility, sperm viability, reacted acrosome and lipid peroxidation assessed in vitro after H2O2-mediated oxidative damage in spermatozoa. Sixteen patients (mean age: 35 years; range: 25-45 years) referred to the Histology-Embryology Laboratory of the Medicine Faculty of Sfax for semen analysis after 12-24 months of sexual intercourse without conception were selected. After spermiogram, sperm selection by two-interface discontinuous Sill Select gradient was performed, and selected spermatozoa were used in four experimental assays: control; incubation with 100 microm H2O2; incubation with 0.1% DSO; and co-incubation with 0.1% DSO and 100 microm H2O2. Motility and viability were determined using World Health Organization criteria. Acrosome reaction and lipid peroxidation were assessed by staining with fluorescein isothiocyanate-Pisum sativum and spectrophotometric measurement of malondialdehyde, respectively. Results showed that incubation with H2O2 alone led to a significant increase in lipid peroxidation (57.83%, P<0.05) associated with a significant decrease in sperm motility, sperm viability (after 30 min and 24 h) and percentage of reacted acrosome (P<0.05). Date seed oil improved sperm motility after 24 h of incubation (P<0.05) and protected spermatozoa against the deleterious effects of H2O2 on motility, viability, acrosome reaction and lipid peroxidation. We conclude that supplementation with DSO may have a function in antioxidant protection against male infertility.

A comparative study of oxidant-antioxidant status in stable and active vitiligo patients.

The pathogenetic mechanisms in vitiligo have not been completely clarified. One of the major hypotheses in the pathogenesis of vitiligo is the oxidative stress hypothesis. The active or stable phase of vitiligo is defined on the basis of the progression or appearance of new lesions in the last 3 months and the absence of new lesions or their progression in the last 6 months, respectively. Eighteen patients with active vitiligo, 18 patients with stable vitiligo, and 40 controls were included in this study. We examined serum levels of malondialdehyde, selenium, vitamin E and A, and the erythrocyte activities of glutathione peroxidase, superoxide dismutase, and catalase. Our results revealed a significantly higher level of serum malondialdehyde, selenium in patients with active disease compared with the controls. Significant higher increase in erythrocytes superoxide dismutase activities was observed in active vitiligo group, erythrocyte glutathione peroxidase activity was decreased significantly in active disease, whereas erythrocyte catalase activity and plasma vitamin E and A levels were not different in vitiligo patients as compared with controls. Our study shows that oxidative stress is involved in the pathophysiology of both active and stable vitiligo but increased imbalance of antioxidants was observed in the blood of active vitiligo patients.