Elastatropin® in Scalp & Hair Conditioning
The loss and thinning of hair is a troubling experience for many men as they age, and even for some women. Male pattern baldness can begin in early adulthood for a few individuals, and leads to the eventual complete loss of hair except for a "fringe" around the sides of the head.
The causes of hair thinning are more diverse than most people realize although much attention has been focused on the activity of testosterone and dihydrotestosterone (DHT). Testosterone and DHT are known to be factors in male pattern baldness, but many men have high testosterone metabolite levels and never suffer from male pattern baldness. It has been suggested that a combination of factors, including a person’s genetic background and the impact of the environment on that background, are responsible for hair loss and thinning. What is known is that in some men, DHT causes an increase the length of time that the hair follicles are dormant, producing thinner, slower growing hair. The most widely used hair loss treatment, Rogaine?, does not block DHT or its activity. This drug stimulates production of the hormone Vascular Endothelial Growth Factor, and increases the vascularization (blood flow) in the dermal pappila.
Figure 1. Follicle-associated elastin in the scalp of a human infant.
Hair follicles in the scalp of mammals, including humans, are intimately associated with and responsible for the production of scalp proteins such as elastin. The elastin fibers in the upper dermis are exclusively synthesized by the cells lining the root sheath in the hair follicle1. This establishes an intimate connection between the hair follicles and the extracellular matrix that supports the follicles in the skin. There is growing evidence that other reasons, including damage to the proteins in the scalp from sunlight and environmental factors also cause thinning and loss of hair. This is a self-reinforcing problem, because as hair thins and becomes more sparse, greater amounts of sunlight, in particular in the UV range of the spectrum, can penetrate to the scalp and damage the proteins in the scalp matrix. For example, there are significant difference between the elastin in the scalp of infants compared to adults. Figure 1 shows an elastin-stained section of skin from the scalp of a human infant, displaying organized bundles of elastin associated with the hair follicle2 (HF).
It is apparent from this data that the elastin is both closely associated with and produced by the hair follicles themselves. The synthesized elastin forms dense, well organized bundles running through the epidermis and deeper into the dermis (Figure 2) in the scalp of infants2.
Figure 2. Cross-section of elastin fiber organization in the scalp from a human infant.
Solar damage to elastin in the scalp of adults (solar elastosis) interferes with elastic fiber interactions with each other and with hair follicles, and may be a major contributor to hair thinning and loss (Figure 3). Sections of adult scalp show extensive elastin damage and loss of organization, presumably due to UV-induced changes in the elastin proteins themselves. These figures show a marked change in the elastin in the skin of adults compared to infant scalp skin2.
Figure 3. Section from adult scalp tissue showing hair follicle and elastin fibers.
Not only is elastin and its precursor, tropoelastin, synthesized by the cells in the hair follicles, but the follicles themselves appear to depend on elastin and the structure of its matrix for their function and vitality. A genetic defect in humans termed Menkes’ syndrome results in deficient uptake of dietary copper. Copper is essential for the enzyme that crosslinks elastin in the extracellular matrix, so sufferers of Menke’s syndrome show abnormal arteries – arties have very high elastin content – progressive neurological deterioration and early death3. Another effect of Menke’s syndrome is brittle, fragile and sparse hair, suggesting that the elastin structure in the scalp is important for normal hair follicle function and hair structure.
Further support for the idea that elastin structure in the scalp is linked to and supports hair growth is provided by a mouse genetic model called rough coat4. Mice with the rough coat genetic defect have significantly reduced levels and altered deposition of both elastin and collagen in their skin and internal organs. Rough coat mice also display progressive hair loss – similar to male pattern baldness in humans. These observations strongly suggest that the protein elastin is both synthesized by and essential for the complete functioning of hair follicles. Elastin damage by aging processes and sunlight contribute to the loss and thinness of hair as we age.
One method of restoring elastin lost during aging would be the use of a small molecule that stimuates the body to synthesize more tropoelastin. No safe and effective molecules yet been found that stimulates elastin synthesis in skin. Another approach is to provide human elastin to the scalp in a formulation from an outside source. Human elastin is known from clinical trials5 to penetrate the skin on the face and become absorbed.
We have recently evaluated the topical application of human tropoelastin, the precursor to elastin, to the scalp of a volunteer showing the signs of male pattern baldness. If damage to the structure and matrix of elastin in the scalp contributes to the thinning and loss of hair, then providing an external source of this human protein could help reduce ongoing hair loss and stimulate new hair growth. The elastin formulation was applied twice per day for 5 weeks and the scalp hair photographed, as shown in Figure 4.
Figure 4. Before and after photographs of elastin treated scalp.
These results suggest that a topical application of human tropoelastin may diminish hair loss and even stimulate the growth of new hair.
- Starcher, B., Pierce, R. and Hinek A. 1999. J. Invest. Dermatol. 112(4): 450-455.
- Starcher, B., Aycock,R.L. and Hill, C. H. 2005. "Multiple Roles for Elastic Fibers in the Skin." J. Hist.& CytoChem. 53(4): 431-443.
- Matthai G.S., Sosamma, M.M, Sukumaran, T.U. 2005. "Menkes' kinky hair syndrome". Indian J Pediatr. 72:891-892.
- Hyashi, K. et. al. 2004. "Progressive hair loss and myocardial degeneration in rough coat mice: Reduced lysyl oxidase-like (LOXL) in the skin and heart." J. Invest. Dermtol. 123: 864-871.a. 2006.
- Lamm, S. "Tolerance Study of DermaLastyl-B Face Cream" Cosmetic Design 5/9/06.