beta-Carotene is being used as an oral sun protectant, and evidence indicates that carotenoids may protect human skin from light-induced lesions. However, limited information is available on the distribution and accumulation of beta-carotene in skin, especially with respect to various skin regions. With the use of reflection spectroscopy, we investigated the accumulation of total carotenoids in human skin after repeated supplementation of 12 women with beta-carotene from a natural source Betatene, an algal extract. After daily ingestion of 24 mg beta-carotene (in Betatene) for 12 wk, an increase in carotenoid skin levels was observed. Highest basal values were measured in skin of the forehead, palm of the hand and dorsal skin, with lower levels measured in skin of the arm and back of the hand. Upon treatment, increases in carotenoid skin levels were found in all areas as follows: 2.4-fold in forehead, 0.7-fold in dorsal skin, 2.2-fold in the palm of the hand, 17-fold on the back of the hand and 1.7-fold on the inside of the arm. After cessation of treatment, the carotenoid levels decreased in all skin areas. Serum beta-carotene levels were elevated upon treatment and correlated with carotenoid skin levels. Correlations for serum vs. skin from the palm of the hand (r = 0.94) and skin from the forehead (r = 0.89) were calculated, indicating that serum levels appeared to be a suitable indicator for carotenoid accumulation in specific regions of the skin. With doses of approximately 20-25 mg carotenoids/d, it is possible to raise dermal carotenoid levels.
Following ingestion of a beta-carotene isomer mixture (Betatene) containing nearly equal amounts of all-trans and 9-cis beta-carotene (all-trans/9-cis beta-carotene ratio approximately 1.5), concentrations of all-trans beta-carotene increased for 6 or 8 h in the chylomicron fraction of plasma from four of seven human subjects. A substantially lower increase in the 9-cis beta-carotene concentration was observed, with the accumulation of the all-trans isomer being 10- to 50-fold higher than that of the 9-cis isomer, calculated on the basis of the beta-carotene isomer pattern in the ingested mixture. A similar effect was observed in the VLDL fraction. Three of the seven subjects did not respond to beta-carotene ingestion. In the subjects that did respond, the all-trans/9-cis beta-carotene ratios in chylomicrons and VLDL suggest an efficient isomer-selective mechanism for intestinal uptake across the mucosa or very rapid elimination into tissues.
RRR-alpha-Tocopherol (Vitamin E) was assayed in plasma of 48 patients with viral hepatitis and of 32 healthy controls. In patients with highly elevated serum transaminases (ALT > 100 U/L) vitamin E plasma levels were significantly lower (17.5 +/- 4.8 mumol/L) than in controls (22.7 +/- 4.2 mumol/L, p < 0.01). The vitamin E/lipid ratios (3.12 +/- 0.63 mumol/g) in these patients were 33% lower than those of the controls (4.68 +/- 0.54 mumol/g). The lowered vitamin E levels in patients with acute or chronic viral hepatitis with high activity of disease may be due to free radical-mediated liver injury.
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