The use of peptides has grown a considerable amount over the last five years, but little is mentioned about the efficacy of bioactive peptides. This article will focus on how bioactive peptides work at the cellular level to affect each layer of the skin, including the dermis. To begin, it is important to differentiate between trademarked and bioactive peptides.
According to the American Medical Dictionary, peptides are any member or class of compounds of low molecular weight that yield two or more amino acids on hydrolysis. They are the constituent part of proteins and are formed by the loss of water from the NH2 and Co(OH)2 groups of adjacent amino acids.1 One article states, “of all organic building blocks, peptides are very promising platforms because of their ease of synthesis, chemical diversity, and their similar biological properties to proteins. In addition, peptides are very useful components in creating self‐assembled nanostructures because of their biocompatibility, biodegradability, and bio-functionality.”4
Bioactive is defined as having an effect or biological response on a living organism. There are four rules for peptides to be considered bioactive. The rules are: peptides must possess the correct message, meet threshold requirements, fit into the biological feedback loop, and be received by the target cell. Examples of trademarked peptides are: Matrixyl, Martrixyl 3000, Matrixyl Synthe6, and Argireline. Matrixyl 3000 is a palmitoyl tetrapeptide-7, Matrixyl Synthe6 is palmitoyl tripeptide-38, and Argireline is a trademarked hexapeptide.3
BIOACTIVE PEPTIDE INFLUENCE ON THE LAYERS OF THE SKIN
The dermis, frequently called true skin, contains fibroblasts for collagen, elastin, and glycosaminoglycans formation. In addition, blood and lymph vessels, nerve endings, suderifous and sebaceous glands, hair follicles, and fibrous structures are found at this layer. Bioactive signaling peptides have the ability to signal a response from the fibroblast cells, stimulating the production of new collagen and elastin.
The dermis also contains important immune response cells, such as macrophages, mast cells, phagocytes, and leukocytes. Surrounding the cells of the dermis is the extracellular matrix. The extracellular matrix consists of hyaluronic acid, elastin, and collagen fibers. Hyaluronic acid is an important contributor to the strength of collagen and elastin fibers.2
The deepest layer of the epidermis, stratum germinativum is a portion of a reproductive layer. Cells form and push their way up, become keratinized, and eventually replace the top layer of the stratum corneum. Also found in this layer are melanocytes, keratinocytes, Merkel cells, Langerhans cells, desmosomes, and hemidesmosomes.
The next layer is the stratum spinosum. This layer is considered to be the strength layer because of the spiny fibers. Desmosomes (bridges of communication) are present in the spinosum. Desmosomes are the link between cell to cell communication and, in turn, provide strength and integrity to the epidermis tissues. Bioactive peptides are able to signal the desmosomes and cadherins to provide proper tension and strength to the skin.
The keratinocytes pick up pigment in this layer. When increased exposure to ultraviolet light occurs, the keratinocytes and melanosomes are signaled. Melanin is then transferred to the keratinocytes. Enzyme inhibitor peptides have an opportunity to communicate to the melanocytes to modulate the production of melanin. The goal of these peptides is to block the message of damaged cells that signal melanin production. Once the damaged cells die, the signal is non-existent.
The stratum granulosum layer is primarily responsible for maintaining hydration. This granular layer synthesizes bilayer lipids to assist the stratum corneum with a barrier system. Bioactive peptides provide the cellular communication to produce cellular communication to continue the production of lipids.
The stratum lucidum layer is where the keratinocytes become granular. The lamellar granules release a lipid that repels water. This helps to slow down transepidermal water loss and maintain hydration. Ceramides, filaggrin help with improving the barrier system with a balance of oil and water. Langerhans cells protect from foreign invaders. Bioactive antimicrobial peptides (AMPs) are able to disrupt the quorum of bacteria, providing assistance to fight against invasion.
The outermost layer of the epidermis is the stratum corneum, considered the skin’s barrier or acid mantel. There are approximately 25 to 30 layers of flat, dead cells filled with keratin and surrounded by lipids.2 This layer provides a barrier to ultraviolet light, excessive heat, chemicals, bacteria, and water.
Scientists have discovered that cells do not grow in isolation but thrive in a two-way communication. It is important to understand how the body functions optimally during homeostasis. Bioactive peptides provide the missing link to achieve homeostasis between cells, tissues, and organs.
As cells advance through the stages of aging, there are visible results in the epidermis. Bioactive peptides are able to target each layer of the skin and provide the missing link between damaged and healthy cells. This network of communication ultimately brings the skin back to health or homeostasis. By providing the necessary communication, the cells have an opportunity to become rejuvenated, eliminating a plateau and essentially restoring the skin back to its healthy state.
1 American Medical Dictionary. www.medical-dictionary.com.
2 Barrett-Hill, Florence. Advanced Skin Analysis. Virtual Beauty Corporation, 2004.
3 “Matrixial.” Deciem.com.
4 Hutchinson, J.A., S. Burholt, and I.W. Hamley. “Peptide hormones and lipopeptides: from self-
assembly to therapeutic applications.” Journal of peptide science 23, no. 2 (2017): 82-94.
Susan Wade is a licensed aesthetician joining Viktoria De’Ann in 2015 as the director of education and sales after being in the health and education industry for over 18 years. She has a master’s in higher education administration and enjoys sharing her wealth of knowledge with physicians, clinicians, and students nationwide. Wade has a diverse background beyond aesthetics as a college instructor in kinesiology and business and is an owner of a successful sports conditioning business’ and a nutrition coach. Her passion lies in understanding the complexities of physiology, nutrition, and biology and in educating practitioners on how to incorporate these areas to reach better solutions and successful results with their clients.