Title:  Nutraceutical composition for protection against solar radiation

United States Patent:  6,254,898

Assignee:  Protective Factors, Inc. (Boston, MA)

Filed:  May 25, 2000

A nutraceutical composition, for the inhibition of photochemical damage to the skin and eyes induced by sunlight, particularly by exposure to ultraviolet radiation is disclosed. The blend is multifunctional and comprises a blend of chemopreventive natural products, which exert anti-radical mechanisms of prevention and intervention, anti-inflammatory effects, enhance the endogenous defense mechanisms, and also have the potential to reduce the radiation induced pigmentation. The active ingredients in the blend include green tea extract, lutein (zeaxanthin), lipoic acid, and selenomethionine.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

A nutraceutical composition containing natural products for protecting the skin and eyes from damage caused by exposure to solar radiation is disclosed. The formulation can be used both for prevention of sunlight damage and post exposure treatment. The principle components of the present invention are: green tea, lutein, lipoic acid, and selenomethionine. These ingredients function collectively to ameliorate the various deleterious effects of UV radiation. The mechanism of action of each component has been researched in animal experiments and human studies.

Oral feeding or topical application of green tea polyphenols has been reported to exert significant protection against ultraviolet B radiation induced sunburn lesion formation, erythema, tumor initiation, and tumor promotion in animal experiments (Agarwal, R., Katiyar, S. K., Khan, S. G., and Mukhthar, H., Photochem. Photobiol., 58: 695-700, 1993; Wang, Z. Y., Agarval, R., Bickers, D. R., and Mukhtar, H., Carcinigenesis, 12: 1527-1530, 1991; Mukthar, H., Katiyar, S. K., and Agarwal, R., J. Invest. Dermatol., 102: 3-7, 1994). In addition to a strong free radical quenching activity, green tea polyphenols inhibit the major biochemical markers for tumor initiation (cytochrome P-450 enzyme system) and tumor promotion (epidermal ornithine decarboxylase). Ultraviolet radiation also upregulates the mRNA level for tyrosinase, the rate-limiting enzyme in melanin biosynthesis, which induces the hyperpigmentary disorders (Fuchs, J., Mehlhorn, R., and Packer, L., J. Invest. Dermatol., 93: 633-640, 1989). In a recent study, No, et al. (No, J. K., Soung, D. Y., Kim, Y. J., Shim, K. H., Jun, Y. S., Rhee, S. H., Yokozawa, T., and Chung, H. Y., Life Sciences, 65: 241-246, 1999) have reported that green tea polyphenols inhibit tyrosinase, indicating a potential against prevention of the hyperpigmentation effects.

Lipoic acid (6,8-thioctic acid), an endogenous disulfide, is used in the treatment of liver diseases in which free radical induced lipid peroxidation appears to be involved. Lipoic acid has been shown to provide protection against free radical mediated lipid peroxidation and inflammation in vivo and in vitro (Fuchs, J., Milbradt, R., and Zimmer, G., Free Radical Biol Med., 9: 189, 1990; Bast, A. and Haenen, G. R. M. M., Biochim. Biophys. Acta, 963: 558-561, 1988). Ramakrishnan, et al. (Ramakrishnan, N., Wolfe, W. W., and Catravas, G. N., Radiation Res., 130: 36-365, 1992) have reported that lipoic acid has a protective effect against radiation injury to hematopoietic tissues in mice. Lipoic acid has also been reported to have a protective effect against eye lens damage (Kilic, F., Handleman, G. J., Serbinova, E., Packer, L., and Trevithick, J. R., Biochem., Mol. Biol. Int., 37: 361-370, 1995).

Lutein is a potent free radical quencher and also is highly effective in the prevention and treatment of macular degeneration and lowers the risk of cataract formation. Structural and clinical studies have shown that lutein and zeaxanthin are concentrated in the retinal macular pigment and that such accumulation is dependent on dietary intake (Schalch, W., EXS, 62:280-98, 1992). Animal experiments and epidemiological studies have indicated a protective role of lutein and zeaxanthin in the retina (Pratt S, J Am Optom Assoc., 70: 39-47, 1999). Epidemiological studies also have indicated that intake of spinach (rich in lutein and zeaxanthin) was consistently associated with a lower relative risk of developing cataracts rather than consumption of carrots (high in .beta.-carotene) (Hankinson, S. E., Stampfer, M. J., Seddon, J. M., Colditz, G. A., Rosner, B., Speizer, F. E., and Willett, W. C., British Med. J., 305: 335-339, 1997).

Selenium is essential for the detoxifying activity of the endogenous antiradical defense systems, such as Se-dependent glutathione peroxidase. In animal studies, oral supplementation or topical application of selenium delayed the appearance the skin tumors, reduced lipid peroxidation, inflammation, and pigmentation caused by UV radiation (Burke, K. E., Combs, G. F., Gross, E. G., Bhuyan, K. C., and Abu-libdeh, H., Nutr. Cancer, 17: 123-137, 1992). Human studies have indicated a strong inverse association between plasma selenium levels and non-melanoma skin cancer (Clark, L. C., Graham, G. F., Crounse, R. G., Grimson, R., Hulka, B., and Shy, C. M., Nutr. Cancer, 6:13-21, 1984).

In a preferred embodiment, the composition contains green tea polyphenols as one of the components in about 0.05 to 50 weight percent, wherein the polyphenol content is between 30 to 50 weight percent. Lipoic acid is present in about 0.01 to 10 weight percent of the formulation. Selenomethionine is present at about 0.00001-0.01 weight percent. Lutein is present at about 0.00015-0.15 weight percent, and contains at least 1-2% by weight of zeaxanthin.

While the invention has been described in detail with particular reference to these principle active ingredients, numerous modifications and substitutions can be used to alter the weight percent of the components, incorporate additional bioactive components from natural sources, and to develop more effective, novel molecular complexes combining active ingredients from different sources.

The invention further includes incorporation of the active ingredients into two-piece hard gelatin capsules at about a 150-400 mg level. The capsule includes a natural inert carrier, such as, for example, rice flour at about 37 weight percent, and is suitable for oral administration in discrete units. The composition also is suitable for incorporation into soft gelatin capsules or tablets, each containing a predetermined amount of the active ingredients, for example, as a powder, granules, or a suspension in edible oils.

While the invention has been described with reference to a preferred embodiment, those skilled in the art will understand that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims. In this application all units are in the metric system and all amounts and percentages are by weight, unless otherwise expressly indicated. Also, all citations referred herein are expressly incorporated herein by reference.

Claim 1 of 8 Claims

What is claimed is:

1. A nutraceutical blend for the protection of photodamage induced by solar radiation, the active ingredients consisting essentially of a blend of:

(a) green tea extract that contains polyphenols, said green tea extract content being between about 0.05 and 50 weight percent and the polyphenol content in said green tea extract is between 30 and 50 weight percent;

(b) lipoic acid in an amount of between about 0.01 and 10 weight percent;

(c) selenomethionine in an amount of between about 0.00001 and 0.01 weight percent; and

(d) lutein content is between about 0.00015-0.15 weight percent.

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