Dietary Tocotrienol Reduces UVB-induced Skin Damage and Sesamin Enhances Tocotrienol Effects in Hairless Mice

Abstract

SummaryWe have previously reported that substantial amounts of tocotrienols were present in the skin of animals fed a diet containing a tocopherols and tocotrienols rich fraction (T-mix) extracted from palm oil, and further, that sesame lignans enhanced tocotrienol levels in the skin. The present studies were undertaken to determine whether dietary tocotrienols and those with sesamin could protect the skin from damage induced by UVB irradiation in hairless mice fed four diets: a vitamin E-free diet, a 50 mg/kg ␣ -tocopherol diet, a 229 mg/kg T-mix (with 50 mg ␣ -tocopherol) diet and a 229 mg/kg T-mix with 2 g/kg sesamin diet. In Experiment 1, mice were fed the diets for 6 wk, and half of the mice were exposed to 180 mJ/cm 2 of UVB light once daily for 7 d. After the intensity of sunburn was scored, vitamin E and thiobarbituric acid reactive substances (TBARS) concentrations in the skin and liver were determined. In Experiment 2, hairless mice were initiated with a single application of 7, 12-dimethylbenz[a]anthracene (DMBA), then 1 wk later mice were fed the experimental diets and subjected to 180 mJ/cm 2 UVB irradiation twice weekly for 20 wk. Tumor incidences were counted once a week. Tocotrienols were detected in the skin of mice fed T-mix, but their concentrations were significantly lower than for ␣ -tocopherol. Sesamin elevated tocotrienol contents in the skin. In spite of the high ␣ -tocopherol contents, the effects of ␣ -tocopherol on sunburn and incidence of tumor were slight. T-mix fed groups reduced the extent of sunburn and incidence of tumor, and further reduction of sunburn and incidence of tumor were observed in the T-mix with sesamin group. These results suggest that dietary tocotrienols protect the skin more strongly than ␣ -tocopherol against damage induced by UVB and sesamin enhances tocotrienol effects.

γ-Tocotrienol Promotes TRAIL-Induced Apoptosis through Reactive Oxygen Species/Extracellular Signal-Regulated Kinase/p53–Mediated Upregulation of Death Receptors

“…T3 has been shown to mediate its activity against a variety of chronic diseases, including cardiovascular diseases, neurologic diseases, diabetes, and cancer (9)(10)(11)(12)(13)(14). T3s have shown anticancer activity against cancers such as colon, breast, liver, lung, kidney, prostate, skin, and other cancers both in vitro (15)(16)(17)(18)(19)(20) and in vivo (21)(22)(23)(24)(25). T3 has the potency to induce apoptosis in a variety of cancer cell types (types 1-5).…”

Research advancements in palm oil nutrition

“…Accumulation of tocotrienols in tissue imparts tremendous health benefits . Tocotrienols could help reduce blood cholesterol and arteriosclerotic functions , encompass possible anti‐angiogenic functions , exhibit efficient antioxidant activity as well as anticancer anti‐inflammatory effects , prevention of arthritis , prevention of osteoporosis , prevention of skin diseases , anti‐diabetic , and neuroprotective properties .…”

Acerola (Malpighia emarginata DC.) Juice Intake Suppresses UVB-Induced Skin Pigmentation in SMP30/GNL Knockout Hairless Mice

“…Because chronic UVB irradiation has been known to cause skin barrier dysfunction as well as decreases in the water content of the stratum corneum [31], we measured the water content of the stratum cornea of the three groups during the experiment. As illustrated in Fig 3, the stratum corneum water content decreased gradually in all groups after the initiation of UVB irradiation.…”