From freckles to melasma, pigmentation changes in the skin are a common occurrence most people will experience through different stages of life. However, the causes of hyperpigmentation (also known as dyschromia) are often misunderstood, and the road to correcting discoloration can seem elusive and long.
Pigment changes occur in the skin due to a myriad of reasons, but the primary source of course, is light. That’s right, those cute little freckles are actually the first marker of significant radiation damage in the skin, and evolve later in life to wrinkles, skin abnormalities and skin cancer. Not so cute anymore, right?
Now melsama on the other hand is an entirely different beast. Of course light is the biggest factor to consider when treating melasma (like every skin condition), but melasma is also primarily due to hormonal changes, which makes it one of the more challenging skin conditions to manage. For example, something as simple as getting too warm or enjoying spicy food can trigger the pigment to come back.
Before we dive in deeper, let’s take a look at the basics in understanding pigmentation.
Forms of Pigmentation
There are two primary categories of pigmentation.
1.) Constitutive Pigmentatiuon
Constitutive pigmentation refers to the pigment in skin that is genetically determined without exposure to hormonal imbalances, UV, or trauma. This is the natural pigmentation that determines skin tone, and is NOT a skin condition that requires treatment.
2.) Facultative Pigementation
Facultative pigmentation refers to the pigment that can be induced by inflammation, hormones, and ultraviolet exposure. Unlike constitutive pigmentation, facultative pigment may be reduced or even reversed with treatment. When we talk about hyperpigmentation as a condition, it’s obvious we are talking about facultative pigmentation.
Melanogenesis is the process in which pigment(melanin) is created by the melanocyte cells within the skin. This is the precursor to what is known as dyschromia, or what is more commonly referred to as hyperpigmentation
Melanogenesis is a complex series of biochemical events that begins with the activation of the enzyme tyrosinase- an event referred to as melanogenesis signaling. Melanogenesis signalling can be activated by a variety of intrinsic and extrinsic factors however, they all lead to the same process in the melanocyte cell.
When triggered, the enzyme tyrosinase is released within the melanocyte cell. This creates tyrosine – an amino acid that melanin pigment is derived from. This results in another amino acid,L-3,4-dihydroxyphenylalanine (commonly known as DOPA), setting off the reactions that actually synthesize new melanin pigment. While the process is even more complex than this, you’ll often hear it simplified down to just the initial trigger – the activation of tyrosinase – and the production of melanin.
It all begins in the cell responsible for producing pigment: the melanocyte. Melanocytes are dendritic cells – specialized immunity cells of the body that serve a protective function and are known for their “tree-like” shape. There are approximately 1300 melanocyte cells for every 1 square centimetre of human skin.
These are slow-cycling cells, which means their lifespan is longer than their neighboring keratinocytes – which renew approximately every 30 days in healthy, youthful skin. In comparison, melanocytes are produced during fetal development. Although they can regenerate approximately every 3-5 years, as we age, some of these cells are lost and cannot be restored.
Melanocytes produce granules called melanosomes which contain melanin. Melanin that is pigmented brown/black is called eumelanin, while melanin that is pigmented yellow/red is called pheomelanin. (As humans, we produce both types of melanin- however, the amount and ratio of each will determine our skin, hair, and eye color.) Melanocytes sit among the keratinocytes in the basal cell layer of the epidermis, and transfers the pigment-carrying melanosomes to the cells of the granular layer of the epidermis. As the melanosomes move upwards through the layers of epidermis, the pigment or color will become visible at the surface of our skin.
Melanin Production: A Protective Mechanism
The production of melanin is a protective mechanism of the skin designed to shield the surrounding cells’ DNA from oxidative or physical damage. When the melanocyte is triggered by the threat of damage (from UV rays or other internal or external triggers), melanogenesis is activated andresults in a “pigment dump.” This melanin is then transferred to the surrounding keratinocytes to protect our DNA from the impending threat. Healthy, intact DNA within the keratinocyteis integral to a healthy cellular lifecycle and replication.
While this is a necessary process part of a healthy immune system, it is also what leads to the darker patches of discoloration that we identify as hyperpigmentation on the outermost layers of this skin. Over time, when over used and over-activated, the melanocytes can become damaged and malfunction – leading to varying conditions of hyperpigmentation.
The most important step in correcting and protecting your skin from hyperpigmentation is of course with the use of medical grade skincare products, number one being SUNSCREEN. Without the proper use of sunscreen there is no possible way that hyperpigmentation will ever improve, and is a guarantee that it will appear and accumulate throughout our lifetime. Even missing one sunscreen application can cause pigment to reappear. Sun damage can take up to 30 years to appear on the surface of the skin after the damage is accrued, so even if sun damage isn’t visible the skin’s surface now, it likely will be visible later.
Some great products to include in your routine after you’ve established a solid sunscreen routine include vitamin c, retinoids, and other specific tyrosinase inhibitors like kojic acid, tranexamic acid, ferulic acid, azelaic acid, alpha arbutin or hydroquinone etc. One of my personal favorites is Discoloration Defense from Skin Ceuticals for it’s gentle yet effective qualities. Shop it here https://www.sapienskin.com/collections/skin-ceuticals/products/discoloration-defense
As always, it is best to work with a professional when treating any skin condition so you can get on a plan that gets you the best results.
Now go reapply your sunscreen 😉