Telomeres, the terminal portions of eukaryotic chromosomes, have been established as a culprit of chronological aging. Simply put, with each cell division, human telomere length shortens. Even in relatively inactive skin, fibroblast cells, more than 30 percent of the telomere length, have vanished during adulthood. Perilously short telomeres signal cell hindrance or apoptosis, or cell suicide, (programmed cell death is a developmental process that usually proceeds apoptosis) and depending on cell type, contributes to cellular depletion.
The vast diversity of living organisms is based on a single building block: the cell. Take case in point of the largest body appendage, the skin. This complicated immune organ is made up of billions of cells (19,500,000 per square inch) residing in the epidermis, dermis and sub-dermis, all acting in concert to spawn new generations of skin every 28 to 32 days. The construction of cells is based on several common properties:
- A covering called the plasma membrane isolates the interior of the cell from the external environment. The plasma membrane contains systems that control import into and export out of the cell.
- Genetic material contains the information needed to produce all the cell’s components.
- These cellular components are constructed from food sources using internal systems for energy conversion.
- Gene expression enables the cell to use its genetic information.
- Individual protein products are encoded by genes and upon synthesis, can assemble into larger structures.
The architecture of a cell is circumscribed by a membrane consisting of an important lipid bi-layer that is a macromolecular structure built from lipids and is somewhat permeable to water, but impermeable to ions, small charged molecules and all large molecules. No cell can survive without its repair system and a single irradiation event with ultraviolet (UV) light, such as sunlight, can be lethal. Maintaining the integrity of the cell’s genetic information is equally as important as replicating it accurately.
Individual errors in the DNA sequence occur in two ways. First, mistakes may be made during replication, with the wrong base being inserted into the new chain. Replication systems have proofreading mechanisms to guard against such errors, which reduce corrections to a low rate. Secondly, DNA can be damaged by environmental effects, including radiation or chemicals that modify its bases. A cell contains many repair systems that act to restore a damaged DNA sequence to its original state. In professional skin care, use of a select group of active ingredients and treatments targeted to DNA re-establishment can assist in supporting these repair systems to battle both intrinsic and extrinsic aging.A cell needs to regulate its interior environment to enable its systems to work properly. In particular, ionic levels and pH must be controlled. The impermeability of the membrane creates a need for special systems within the membrane to move ions in and out of the cell.
A cell must import material from the outside and in particular, it is required to import sources of energy and small molecules that are precursors for the components assembled into larger molecules and structures. Fatty acids are used to make lipids, amino acids are used to make proteins, and nucleotides are used to make RNA and DNA.
All living cells have means of converting energy supplied by the environment into the common intermediate adenosine triphosphate (ATP) generated by the cell’s organelle, the mighty mitochondria. Mitochondria are energy factories and are often called the power centers of the (eukaryotic) cell and the most vulnerable to ROS attack. These organelles provide the energy that is required for its metabolic processes and for effecting structural changes.
In order to survive and reproduce itself, a cell must be able to obtain energy from its environment and use that energy to synthesize its own components. Because the production of new cells requires the division of a preexisting cell, a cell must carry within it the information for reproducing all its components. The form of this information is a single type of genetic material, DNA, which codes for all the proteins of the cell. The proteins in turn can assemble into large structures or take responsibility for catalyzing the internal reactions of the cell. The device that is used to interpret the genetic code has the same type of components in all cells. Since a cell is under a barrage of daily ROS attacks from the environment, the means of repairing damage to central genetic information is essential for long-term survival, as in the case of telomeres at the end of the chromosome in the DNA.
Cells perpetuate by dividing themselves. A special cellular tool confers the capability to divide in order to generate two progeny cells, each identical to the parent cell in its content of genetic material and also containing half of the other structures of the cell.
During development, some cells retain the capacity to generate all the cells of specific tissues, while others can generate only subsets of the cells or may in fact be unable to generate any type of cell. These cells with broad activities in regeneration and are called STEM CELLS.
Basic cell science is understanding that cells have a genome that codes for all its structures, a means of expressing genetic information, a system for utilizing energy, and a plasma membrane that controls communication with the outside world, all relative to aging.
Why Cells Age and Die
In 1962, two cell biologists, Dr. Leonard Hayflick and Dr. Paul Moorhead, made one of the greatest contributions to the history of cellular biology by demonstrating the senescence of cultured human cells that led to what is now known as the Hayflick Theory.
Hayflick theorized that the aging process was controlled by a biological clock contained within each living cell. The 1961 studies concluded that human fibroblast cells have a limited life span and divide approximately 50 times over a period of years and then stop. The most evident changes took place in the cell organelles, membranes and genetic material. This improper functioning of cells was concluded to be responsible for the effects of aging.
The understanding of cell death in aging brings to mind many factors that require comprehension of theory, certainty and identity with respect to the culprits suspected to be the driving forces of aging the cells. It is for this reason that we as aestheticians make use of intake forms to assist in the discovery and recognition of many factors to help prevent further skin injury and correct cosmetic damage brought on by aging cells.
Among cell aging triggers, intrinsic and extrinsic, solar UV radiation is the most destructive to DNA and accelerates cell death by causing premature aging of the skin. The sun’s proton energy attacks the cell’s nucleus, scrambling DNA and setting off a sequence of events that speed up the cell’s aging process. Acute sun exposure provokes short- and long-term effects on the skin by damaging cells. Sunscreen is mandatory to prevent further UV ray damage of the skin and is the only recognized wrinkle prevention by the FDA. Sunscreens are no longer a beauty product, but a necessity for skin health.
Cell death also occurs by energy depletion. Mitochondria are the main sources of energy in the cell. They contain their own DNA (mtDNA) and are maternally inherited. Mitochondria are essential for the functioning of all cells in the body and are absolutely critical for the function of those tissues dependent on aerobic metabolism such as muscles and the brain. One treatment substantiated to increase mitochondria ATP energy used in medical spas and skin care clinics is a specialized ultrasonic skin machine. This professional treatment provides the professional the ability to rebalance and assist cells to repair and help transport nutrients, eliminate waste and influence mitochondria to increase ATP energy.
In 2009, three scientists, Elizabeth H. Blackburn, Carol W. Greider and Jack W. Szostak, found out how chromosomes can be copied in a complete way during cell division and protected against degradation causing aging of the cell and were awarded the Nobel Prize for medicine. The solution was discovered at the end of the chromosomes called the telomere.
Within the cell’s nucleus is an integral DNA relative, the all-important telomere that resides on the end of the chromosomes. Telomeres are tandem repeats of a short sequence extending for several thousand base pairs at the end of each chromosome. Telomeres do not encode genes but rather protect the proximal genes and regulatory sequences in several ways. First, absence of telomeres, they serve to protect the chromosomal ends from degradation and fusion, accelerates aging of the cell.
Studied for over two decades, in 2009 telomeres became a recognized and established factor in aging. A telomere is the section of DNA found at the tip of each chromosome in cells and delays aging of the cell. Telomeres are essential for chromosome duplication during cell division.
The aging process is complex and depends on many factors described in this editorial. Therefore, how can telomere cell aging be prevented and potentially reversed? An ancient Chinese herb from a perennial plant called Astragalus Menbranaceus has been established to protect and help lengthen the telomere. This ingredient can be found in only a few professional efficacious formulations that support the DNA health of the skin.
Also duly noted, part of the complex cell aging process is the essential stem cell. Stem cells have a limited life span due to UV radiation, smoking, ozone, DNA damage, oxidative stress and telomere shortening. A cell’s lineage begins with stem cells and telomere shortening occurs even in stem cells during replicate aging. Because stem cells are responsible for making skin, it is important to incorporate telomere maintenance in human stem cells due to the complex process tightly linked to cell cycle regulation.
The use of plant stem cells, comparable to human stem cells, to protect skin stem cells is the basis of the acclaimed Uttwiler Spatlauber Apple extract that up-regulates specific genes involved in protection against oxidative stress, repair of DNA, and delay of cell senescence. This action gives rise to the benefits of the use of plant stem cells to assist epidermal stem cells in homeostasis. Found in professional serums, stem cell formulations have been substantiated to be critical in the war against cell aging and should be used daily.
According to Dr. August Weisman, cell aging also occurs when there is overuse and abuse to the body. Skin is worn down by toxins in our diet and environment; excessive consumption of fat, sugar, caffeine, alcohol and nicotine.
Scientist Vladmir Dilman, Ph.D., also elaborates on the wear and tear theory by focusing on the neuroendocrine system, a complicated network of biochemicals that govern the release of our hormones and other vital elements. Noted in his discovery is that as we age, the body produces lower levels of hormones, which can have disastrous effects on the skin and body functions. Hormones are vital for repairing and regulating our body performance and if our hormones are being produced at youthful levels, in a very real sense the cells of our bodies are stimulated to be metabolically active.
While we are aware of external factors relating to UV rays that cause cellular breakdown and eventual cell death, scientific evidence points to another culprit – glucose driven intrinsic aging. Glucose is a vital cellular fuel. However, based on the accelerated rate of aging seen in diabetics, chronic glucose exposure has long been known to affect how the body ages by a process called glycation.
The same browning reaction that occurs when you cook meat at a high heat takes place at a slower rate to long-lived tissue proteins such as collagen. Similarly in the human body, once sugars enter the circulation, they attach themselves to the amino groups of tissue proteins such as collagen to slowly rearrange the youthful structure into the main culprits of damage called advanced glycation end products (AGEs). Glycation directly increases the release of matrix metalloproteinase (MMP-1) which breaks down collagen and although this action takes place internally, external sources of oxidative stress cause a double dose of danger, leading to accelerated aging.
Genetic programming also affects cellular aging. By protecting and augmenting the basic building blocks of DNA within each of our cells, preventing damage to and increasing repair of DNA becomes an important part of a skin care treatment and home care regimen.
The free radical theory of cellular aging has long been established as an integral part of aging and was first introduced by R. Gerschman but developed by Denham Harmam in 1954. Free radical is a term used to describe any molecule differentiated from conventional molecules that possess a free electron – a property that makes it react with other molecules in highly volatile and destructive ways. Free radicals attack the structure of cell membranes, thereby creating waste products, including substances known as lipofuscins that in turn interfere with the cell’s ability to repair and reproduce themselves. Retinol, as formulated in skin serums and peels, diffuses lipofuscin toxins and is recommended for clinical professional treatments and daily home care in addition to many other water and lipid soluble antioxidant skin care products for both internal and topical use to treat free radical aging.
In conclusion, cellular aging is a complicated 24 hour, seven day a week battle against the decomposing process of skin cells. Consequently, the dissolution of this process which results in the aging of skin has no room for lazy aesthetics! As licensed professional aestheticians, it behooves us to continue to seek out consistent education to feed the mind but also search for established skin care companies that provide advanced skill set training techniques in age management, forward-thinking product formulations, and professional peels that combat aging cells. A word of advice, I always tell my clients, “Your skin will be older tomorrow than it is today. It is my job to prevent that from happening.” Yes, we cannot stop chronological intrinsic aging as set by our biological clock, but it is possible to manage extrinsic aging and reset the skin’s aging clock, realistically turning it back by 10 or 15 clinical years, with proper skin care formulations and treatments. I know because I am living proof of it.
Christine Heathman C.M.E., L.M.T. is a licensed master aesthetician, aesthetic pioneer and nominated Legend in American aesthetics who has practiced clinical skin care for over 25 years. She is a powerful speaker, world-wide lecturer, educator, and author of several skin manuals. Owner and CEO of GlyMed Plus, a professional only skin care line, she has appeared several times on the popular health care program, The Doctors. Heathman has remained loyal to the professional, applying her extensive knowledge and experience to facilitate American aesthetics and remains a commanding and authoritative influence in the skin care industry today.