Wednesday, 20 July 2016 10:20

The Ultraviolet-Induced Impact of Sun Exposure on the Skin

Written by   Dieter Kuster, Ph.D.

"Sunshine on my shoulders makes me happy / Sunshine in my eyes can make me cry," is a wise lyric that says it all. Without the sun, there would be no life on Earth; however, the same can be said of too much sun. It can be both life-giving and life-taking at the same time.

Most people love and enjoy the sun. Those who live in the northern hemisphere can hardly wait for spring and summer to come and provide time to enjoy the outdoors.

At the same time, people who live in the South often forget how lucky they are to have so much sunshine. Regardless of permanent residence, the sun is the reason that most people will travel to warmer and sunshine-drenched areas.

Breaking Down the Effects of Ultraviolet Radiation cell
Ultraviolet radiation from sunlight is known to be an environmental human carcinogen. The most negative effects of ultraviolet irradiation of the human skin are sunburn, immunosuppression, photoaging, and skin cancer. Ultraviolet radiation damages collagen fibers, accelerates the appearance of skin aging, and disrupts the supply of vitamin A. All negative effects on human health, however, can be prevented by using proper precautions. It has been proven that the daily use of a skin care product with an SPF of 16 results in up to 40 percent fewer squamous cell carcinoma lesions of the skin. Therefore, sunscreen products and agents should be incorporated into daily-use skin care products.

In an ever-changing global market, which grew to over $10 billion in 2015, sunscreen formulators and manufacturers are encountering big challenges as they are faced with more and stricter regulations and oversight. FDA regulations and labeling guidelines now dictate that sunscreens that protect against both UVA and UVB rays must be labeled as broad spectrum.

UVA is present every day in significant amounts, even indoors. With its longer wave lengths, UVA rays penetrate deeper into the skin; the energy-rich radiation damages organic molecules like proteins, lipids, and DNA. The strongest UVA-absorbing compounds in nature are mycosporine-like amino acids. These water-soluble substances are found in a number of lower organisms, such as cyanobacteria, red algae, dinoflagellates, coral, and many marine invertebrates. Red algae Porphyra umbilicalis, commonly known as nori, reduces sun exposure and – along with an array of FDA-regulated raw materials or compounds developed for the purpose of reactive oxygen species protection – is a must.

Sunscreens that are properly formulated into a liposomal formulation have several purposes, including scourging free radicals and reflecting the damaging UVA and UVB rays. In the United States, SPF is controlled by the FDA and is considered an over-the-counter product. Very stringent requirements must be fulfilled in order to receive FDA approval.

Using Sunscreen the Right Way
Proper sunscreens guard the skin from sun damage by decreasing the penetration of solar ultraviolet rays into the skin via absorption and/or reflection. The use of a high SPF does not provide 100 percent protection to the skin. In actuality, a high SPF might drive clients to remain exposed to the sun for much longer, without any acute warning signs. It is vital to remember that the activity and/or photostability of filters have a limit.

Furthermore, overuse of high SPF-protection products have a negative impact on the environment and its inhabitants, especially aquatic organisms. High-SPF products are also associated with potential allergies and sensitization effects, as well as the reduction of the biosynthesis of vitamin D. There is also a possibility that more free radicals could be formed, which would lead to oxidative stress.

Reapplying sunscreen while exposed to ultraviolet radiation is highly important. Any improvements clients can make in regard to their skin condition will impede the effects of premature aging. Skin care professionals should be aware of all of the damaging effects of the sun and give knowledge and warning to their clients. The following statement is a great motto to relay to clients: be wise – treat your skin nice; looking good and feeling good is the ultimate reward. 

Photoaging face
Photoaging is the super-position of chronic ultraviolet-induced damage on intrinsic aging and accounts for age-associated changes in skin appearance. Cutaneous changes – which are sun-induced – vary among individuals, reflecting inherent differences in vulnerability and repair capacity for solar results.

Photoaged skin appears deeply wrinkled and discolored and is characterized by a loss of elasticity. Overexposure to ultraviolet radiation, especially between 11 a.m. and 3 p.m., will induce extensive changes in the composition and architecture of the extracellular matrix-rich dermis. UVA radiation penetrates to a greater depth than UVB radiation, but both may be responsible for chronic photoaging. UVB radiation is the major cause of direct DNA damage and induces inflammation and immune suppression, as well as the synthesis and release of prostaglandins, particularly PG2.

Ultraviolet radiation produces reactive oxygen species that activate the transcription factor that induces the expression of pro-inflammatory cytokines. Melanin, which is produced by epidermal melanocytes, absorbs ultraviolet radiation and, therefore, acts as a natural sunscreen, protecting the DNA and proteins of the basal layer cells – particularly stem cells.

A photo-oxidative reaction is initiated by ultraviolet radiation, impairing the antioxidant status and increasing the level of reactive oxygen species. These changes overwhelm the skin's defense capacity and impair the ability of the skin to protect itself from the damaging effects of reactive oxygen species, resulting in extreme damage to the skin.

quoteA continuous regeneration of reactive oxygen species will have a damaging impact on the mitochondrial DNA. If a mutation of DNA is stimulated, it will have a negative impact on the mitochondria and, therefore, create more and more damage to the DNA. In return, mutations of the mitochondrial function – which decrease energy production and protection from reactive oxygen species damage – will increase. This vicious cycle has negative consequences on a person's well-being and appearance.

These changes are the principle causes of aging or age-related diseases. The extent of damage to the DNA brings about photodamaged skin, which compromises cells' ability to regenerate energy for self-preparation. Therefore, a cell's capacity to repair itself is related to photodamage severity rather than chronological age.

womanDamage-Protecting Ingredients
Natural protectants like sunflower sprout extract, and specially formulated peptides with vitamin E, are being researched more and more. A compound developed from Krameria lappacea root (rhatany root) has been used for many years as a natural sun protection, but is not recognized as such by the FDA. Recently, more research has shown that Krameria lappacea has antioxidative, antimicrobial, and anti-inflammatory efficacy with a specific target towards the radiation of UVB rays and the absorption of UVA damage; it is ideal for boosting personal care cosmetics and sun care as prophylaxis against skin aging. It also supports the endogenous repair system of the skin and reduces antioxidative stress and the formation of lipid peroxides.

SPF-formulated products should contain ingredients that protect and strengthen the mitochondria, such as scavenging enzymes like superoxide dismutase, catalase, and different antioxidants. CoQ10, also known as ubiquinone, and lipophilic molecules present in cellular membranes boost the activity of the mitochondria's essential role as a carrier of electrons in the electron transport chain. CoQ10 declines with age, but can be effectively replenished in the skin with topical formulations that are properly formulated. A full integration into the mitochondria is crucial.

The ability to use technology in regards to peptides has opened the door to the creation of many exciting materials regarding sun protection. By taking advantage of microtechnology, it is possible to introduce many materials derived from plants, fruits, and seaweeds into peptides, which boost the ability of penetration, balancing and protecting the skin against damage arrived from reactive oxygen species. Peptides also help to stimulate the moisture balance in the skin, which, in turn, helps to protect and improve reactive oxygen species-exposed skin.

Ingredients that retain moisture for a longer time in the skin, like sodium hyaluronate, collagen, hydrolyzed proteins, and combinations of amino acids in the form of peptides, are also must-haves. Therefore, a good application of moisturizers for the face and body is crucial before sun exposure. Experience shows that water can be burned. For example, a wet tissue under a magnifying glass demonstrates that steam will escape. It is only after all of the moisture is gone that the tissue will burn. This same principle applies to the skin. Skin only starts to get irritated when all or most of its moisture has escaped. The human body consists of 65 percent water, making it more liquid than solid by a margin of almost two to one. It is crucial for professionals to emphasize the importance of using products with high-moisturizing values.

By making use of organic, inorganic, and natural herbal ingredients, the developers of sun care products can establish formulations that provide the ultimate results. Remind clients that they can enjoy the sun, but should always use common sense. The sun can be either life-enhancing or life-destroying; its role is up to them! spf

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Dr.-Dieter-KusterDr. Dieter Kuster is the founder of CA BOTANA International. He has developed over 3,000 products for the cosmetics industry including the in-house brands Doctor D. Schwab, Sea Enzyme, and Ambrosia Aromatherapy. One of his breakthrough achievements is the development of the highly acclaimed molecular penetrator Alphasomes®, an advanced delivery system to increase product effectiveness. His other specialties include target-specific enzymes and superior peptide technology. During his 50-plus years of experience, he has authored many articles for magazines and trade publications and is a sought-after lecturer and speaker for the beauty industry on an
international level.

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