How are stem cells used in cosmetics?

What are stem cells?

Physiologically speaking, stem cells are clusters of undifferentiated cells ready for replication. Around 1-2% of the cells in the basal layer of the epidermis are epidermal stems cells: they will replicate to renew epidermal skin cells continuously and become the layers of the skin.

In younger skin, it takes around 4 weeks for the new basal epidermal cells to migrate to the outer epidermis, providing us with a fresh and rejuvenated appearance. As we age, however, the rate of epidermal skin cell differentiation and subsequent skin cell regeneration at the basal layer slows, as does the skin renewal process. What we see is duller looking skin, uneven skin tone, sagging skin with fine lines and wrinkles, and a devitalised appearance.

If we can support the activity of the epidermal stem cells, however, we can improve the rate of production of the epidermal skin cells to reverse, or at least halt, these signs of ageing and restore a more youthful appearance.

Stem cell technology can also be used on hair follicle stem cells, as their rate of differentiation and replication also slows as we age. There are specific cosmetic stem cell actives to address the signs of hair follicle ageing, combat hair thinning, and slow hair and colour loss as well.

 

Where do cosmetic stem cells come from?

Cosmetic stem cells come from plant stem cell cultures, where selected sources have been clinically proven to support and nurture epidermal stem cell development. The chosen plant sources are usually cut to cause a natural process of ‘healing’ called callus formation. These callus cells are undifferentiated stem cells which can then be collected and cultivated to reproduce, and extraction methods conducted to obtain the stem cell extract in commercial quantities.
 

What proof is there of plant stem cell efficacy for human skin?

Before being launched as a cosmetic ingredient, plant stem cells are checked for potency, safety and efficacy using various in vitro models. As you can see in the image below, the use of plant stem cells on older epidermal stem cells can lead to epidermal skin renewal rates similar to that of younger skin. 

What we see is a thicker epidermal layer, more even skin tone and more youthful appearance. In vivo results show a plumping of skin such that it appears more supple with fewer lines and a younger looking complexion.

How do cosmetic stem cells differ to medical stem cells?

The stem cells used for cosmetic actives are based on plant biotechnology using selected plant stem cells. Medical stem cells, however, are cultivated from human tissue, and subject to far greater ethical and medical scrutiny because of their origin and applications.

Understand the use of stem cells in cosmetic formulas further by watching this video.
 

What are the benefits of choosing plant stem cell actives?

Plant stem cell actives have many advantages in cosmetic formulas such as:

• significant clinical research behind their development: this research starts at an invitro level, where safety and efficacy must be demonstrated. Once this data has been proven and collected, in vivo tests can be conducted to confirm beneficial results.
• sustainable sourcing: because of the way plant stem cells are cultivated and produced, there is no risk of overharvesting or seasonal impacts. They also use very low carbon inputs, making them an incredibly sustainable cosmetic ingredient.
• controlled production: plant stem cells are produced in a controlled environment, meaning the active ingredient is not subject to variations. This results in a highly refined and pure end product with known efficacy.

In terms of visible results, you can expect to see:

• advanced visible anti-ageing results with in 28 days; or
• with certain plant based stem cells, dramatic improvements to hair follicles;
• antioxidant benefits, which protect skin stem cell longevity and function;
• reversal in signs of ageing such as improvements to skin tone and texture; or
• for the hair, redensifying benefits and/or return to more natural hair colour.
   

How do you formulate cosmetics with stem cell actives?

Plant stem cell cultures work best when they achieve delivery to at least the stratum granulosum (mid layers of the epidermis) or ideally, the basal layers of the skin. It can be very difficult to ensure cosmetic ingredients can traverse so many layers of the skin (watch this video for a detailed explanation). However, once you can get the stem cell actives to reach these deeper layers of the epidermis, you only need a very small amount of plant stem cell culture for outstanding visible results.

Cosmetic stem cell actives are best formulated using osmolytic delivery agents in an amphiphilic (emulsion) base. For tips on how to create cosmetic formulas with effective delivery, learn about enhanced delivery ingredients and methods by watching this video.

How to source cosmetic stem cell actives

A growing number of suppliers offer a vast array of plant stem cell actives based on various plant sources. When choosing which suppliers and cosmetic stem cell actives you want to use:

• search cosmetic ingredient databases such as UL Prospector;
• remember to check the individual efficacy data for the amount of cosmetic active required and what results have been proven; and
• speak with your existing suppliers and look for new suppliers at conferences and in-cosmetics exhibitions.

Your selected plant stem cell extract may also boost your product marketing story and add to your brands’ sustainability message!

Finally, keep in mind that your marketing claims must be based on visible anti-ageing (or hair densifying/colour renewal) results to comply with cosmetic regulations in a well formulated base product for the best delivery and results.

Now, it’s over to you to get researching, and creating, highly active skin (and hair) care products using stem cell technology.
 

Happy formulating!