Acetyl Tetrapeptide-3 versus Minoxidil in the treatment of alopecia.

Each individual's head is estimated to have around one million hair follicles, capable of producing up to 150,000 hairs. Each hair has its own unique life cycle which unfolds in three stages: the anagen phase, or growth phase, the catagen phase, or resting phase, and the telogen phase, or shedding phase. The lifespan of a hair ranges from 2 to 7 years depending on the individual. Once its cycle is complete, the hair follicle begins a new one. It is estimated that each hair follicle will undergo an average of twenty cycles until it is exhausted.

However, certain factors can disrupt the hair life cycle and promote hair loss. The causes of alopecia are numerous: heredity, hormonal disruption, stress, diet... It is estimated that a hair loss is abnormal when it is more than 150 hairs per day. Certain cosmetic treatments or medications can help limit hair loss when it becomes greater than normal. The proposed formulas generally work by promoting growth or slowing down losses.

Theacetyl tetrapeptide-3 is particularly used in the haircare field to prevent hair loss. From a mechanistic perspective, this peptide works by increasing the synthesis of type III collagen and laminin, proteins of the extracellular matrix (ECM), which ensures a better anchoring to the hair. The ECM is composed of a collection of macromolecules and provides support and structure for cells and tissues. By influencing the production of ECM proteins, acetyl tetrapeptide-3 helps to increase the size of hair follicles. Several studies have indeed shown that their size is correlated with the synthesis of ECM compounds. Thus, when hair follicles are larger, hair is better anchored and the risk of hair loss is reduced. Moreover, the acetyl tetrapeptide-3 is a very gentle active ingredient suitable for sensitive scalps.

Minoxidil is an active substance often incorporated into treatments for alopecia. Its topical application stimulates the growth of keratinocytes. It's worth noting that these cells cover approximately 90% of the epidermis and appendages, including hair, body hair, and nails. This effect of minoxidil on keratinocytes allows it to extend the growth phase of hair. Furthermore, some studies suggest that this medication works by stimulating the transition of hair follicles from the telogen, or shedding phase, to the anagen, or growth phase. Minoxidil is an effective treatment for alopecia, however, it's not uncommon for it to cause scalp irritation, resulting in redness and itching. Its use is also discouraged in cases of skin problems such as eczema or psoriasis.

Minoxidil is an effective treatment for alopecia, however, it is not suitable for the most sensitive scalps. In search of a gentler alternative that is just as effective, researchers conducted a comparative study between minoxidil and a combination of extracts. This latter formulation contained acetyl tetrapeptide-3, biochanin A, and ginseng. The researchers recruited around thirty individuals suffering from alopecia and divided them into two groups. For 24 weeks, individuals in the first group applied a 3% minoxidil solution to their scalp twice a day, while those in the second group applied the extract.

Following the experiment, scientists observed a comparable improvement in alopecia in individuals from both groups, in terms of the amount of hair loss and overall hair density. They particularly noted a rise in hair density of 8.7% in individuals from the "minoxidil" group compared to an increase of 8.3% in individuals from the "extract" group, which does not represent a significant difference. The tolerance of both products was also studied. No adverse effects were reported following the use of the extract, while one individual developed contact dermatitis after applying the 3% minoxidil solution.

We can thus cautiously conclude that this extract based on acetyl tetrapeptide-3 has the potential to replace minoxidil, given that it has a similar efficacy and is better tolerated. However, further studies involving more participants and extending over longer periods are still necessary to be able to assert that acetyl tetrapeptide-3 is a better treatment than minoxidil in the case of alopecia.

• HOCQUAUX M. & al. A new strategy to modulate alopecia using a combination of two specific and unique ingredients. Journal of cosmetic science (2013).

• PANCHAPRATEEP R. & al. An Herbal Extract Combination (Biochanin A, Acetyl tetrapeptide-3, and Ginseng Extracts) versus 3% Minoxidil Solution for the Treatment of Androgenetic Alopecia: A 24-week, Prospective, Randomized, Triple-blind, Controlled Trial. The Journal of clinical and aesthetic dermatology (2020).