Image by Esther Merbt from Pixabay

In summer we expose our skin to high doses of solar radiation that can seriously harm it. The most immediate effect of prolonged exposure to the sun, without adequate protection, is the appearance of sunburns on the skin in which redness appears accompanied by a continuous sensation of heat and itching.

At long term, the sun’s ultraviolet radiation reduces the quality of the skin by promoting the appearance of spots and decreasing its elasticity, what causes the appearance of wrinkles. Ultraviolet A (UVA) radiation is able to reach the dermis where it damages cellular proteins such as collagen and elastin that provide stability and firmness to the skin [1].

In the most severe cases, prolonged exposure to the sun can lead to dermatological diseases such as sun allergy or even skin cancer.

What is sun allergy? 

We know the most common allergies such as food or tree pollen, but is sun allergy really an allergy? 

To put it simply: NO 

Allergies are immune reactions to a foreign element (allergen), understood as foreign to the body of the allergic person. The immune system recognizes the allergen and reacts neutralizing him. As a consequence, a symptomatology occurs that, in the case of the skin, typically manifests as eczema, hives and itching.

These symptoms associated with allergy are very similar to those that certain people develop after sun exposure, which makes them considered as sun allergy. These skin disorders are solar polymorphic rash, solar urticaria, photodermatitis due to the use of certain medications along with sun exposure and actinic prurigo [2].

All of them present with more or less extensive skin lesions and itching. Therefore, the most efficient way to prevent this type of skin problems is to use adequate sun protection, with the exception of drug photodermatitis, where it is convenient to wait 72 hours after taking a medicine prior sun exposure. 

What happens in the skin when we burn 

Sunburns occur when exposure to ultraviolet radiation exceeds the ability of the skin’s melanin to protect it. This is the reason why people with lighter skin tones, and therefore with a lower level of melanin, are more likely to suffer sunburn.

The skin’s response to prolonged exposure to ultraviolet radiation is inflammation, which is intended to eliminate damaged skin cells [3]. These cells must be removed because their nucleic acids (DNA and RNA) are damaged and therefore, susceptible to become tumour cells.

Damaged keratinocytes release RNA after UVB irradiation and this is sufficient to induce cytokine production in non-irradiated keratinocytes. These cytokines are responsible for triggering the inflammatory response [4] that aims to eliminate damaged cells. 

In general, burns can be divided into three types depending on skin lesions:

• First-degree burns: These are superficial burns since they only affect the epidermis. They manifest as redness, dryness and pain, but do not show long-term damage and usually improve after 24/48 hours.

• Second-degree burns: They affect the epidermis and part of the dermis. They manifest with redness, inflammation, blistering and pain. These lesions usually recover within a few weeks, however, maintaining good hygiene of the affected area is necessary to avoid further damage and infections.

• Third-degree burns: In this type of burns the epidermis is destroyed and the entire dermis is also affected. The burned area is dried and swells, becoming thickened to maintain its protective function. The treatment and recovery of this type of lesions depends on the severity and extent of the affected area [5]. 

Innovation in the development of photoprotectors 

To prevent the harmful effects of the sun and to maintain a good tan throughout the summer it is essential to make good use of sunscreens.

The protectors contain sunscreens as active ingredients, that prevent ultraviolet radiation from passing but allowing another type of radiation to enter that is what allows us to tan. There are various types of sunscreens, mainly classified in organic and inorganic, and their development is in continuous innovation. In order to know the new approaches in the development of new sunscreens, I invite you to visit the Beauty Cluster Barcelona blog where they have compiled the latest trends in the development of photoprotectors. 

Itching in burns 

Although sunburn is usually first grade and tends to improve after 1 or 2 days, the sensation of constant heat and itching is annoying and prevents sleep. For this reason and in order to improve the quality of the injured skin and to repair the damage from burns, it is very important to rehydrate the burned skin, using specific moisturizing creams or lotions for care after sun that contain active ingredients that soothe itching.

The active ingredients that soothe the itching sensation add value to a lotion after sun exposure by immediately relieving one of the most uncomfortable manifestations of sunburn.

Innovation in the design of active ingredients against itching

At AntalGenics, we have extensive knowledge about the sensory innervation of the skin. We work to develop new, safe and innovative molecules that reduce the sensation of itching and are designed to be incorporated into dermatological final formulations.If you want to know more, visit our R&D section or contact us.

Bibliography

  1. Flament, Frederic & Bazin, Roland & Laquieze, Sabine & Rubert, Virginie & Simonpietri, Elisa & Piot, Bertrand. (2013). Effect of the sun on visible clinical signs of aging in Caucasian skin. Clinical, cosmetic and investigational dermatology. 6. 221-232.
  2. https://www.quironsalud.es/blogs/es/alergiate-dia/mal-llamada-alergia-sol
  3. https://scienceillustrated.com.au/blog/science/what-happens-when-we-get-sunburnt/
  4. Bernard, J. J., Cowing-Zitron, C., Nakatsuji, T., Muehleisen, B., Muto, J., Borkowski, A. W., … Gallo, R. L. (2012). Ultraviolet radiation damages self noncoding RNA and is detected by TLR3. Nature medicine, 18(8), 1286–1290.
  5. https://www.stanfordchildrens.org/es/topic/default?id=clasificacindelasquemaduras-90-P09576