A Real Verdict on Skin Health
It's Wednesday night, and one of your favorite TV shows is on. Each commercial break is filled with advertisements for cosmetics and pharmaceutical products related to skin health. It pisses you off because you've struggled with skin problems for years and spent money on products that promise to make your skin glow. It's not just external factors that determine the health of our skin. Your epidermis's health is significantly affected by internal variables. It is said that your skin functions as a "mirror" reflecting the health of your internal organs. It is imperative to be aware of the strong correlation between gut health and skin health. When your inner health is not aligned, you may experience skin problems. A yellowish tinge to the skin is a sign of jaundice, which is caused by excessive amounts of bile in the blood and subcutaneous tissues. Let's cycle back a bit and review some of the key players, structures, and functions that keep your skin looking Niiice.
The skin's anatomy can be summarized as follows:
The skin is the largest organ in our body. It consists of three main regions.
· The epidermis
· Dermis
· The hypodermis
Each region differs in structure and function. There are various layers within each regions. Imagine a sandwich cake in which layers of frosting, jam, and other fillings hold the different regions of the cake together. A cake's fillings are its sublayers.
First at the bat is the Layers of the Epidermis: The actual skin and layer beneath it
In the following list, the strata are listed from the innermost layer to the outermost layer. Stratum = sheet
1. stratum basele
2. stratum spinosum
3. stratum granulosum
4. stratum lucidum
5. stratum corneum
basele sheet: In the epidermis, stratum basele serves as the basement, which is distinguished from the dermis by the basal lamina (a filling). In this layer, stem cells are activated to produce keratinocytes. Melanocytes are also present in this sublayer. A discussion of these cells will follow shortly.
spinosum sheet: Dendritic cells are housed in 8 to 10 cell layers. Dendritic cells are like generals rounding up their troops. They provide them with weapons, handcuffs, and a game plan on how to detain, and remove an infection or unrecognized substance from the skin.
granulosum sheet: In this layer, there are keratohyalin granules and lamellar granules. The keratohyalin granules contain the building blocks for keratin, which later aggregates, overlaps, and becomes bulky. Keratin contributes to the creation and maintenance of the outer skin, hair, and nails. Lamellar granules bind cells together through their glycolipid properties (sugar fat molecule).
lucidum sheet: Despite having just two to three cell layers, this sheet is more prominent on thick skin, such as the palms and soles. In this stratum, a protein called eleidin, a by-product of keratohyalin, is present in a clear sheet. At the end of the process, it will become keratin in the stratum corneum.
corneum sheet: There are 20-30 layers of cells in the actual skin. It is made up of keratin and dead keratinocytes (also known as anucleate squamous cells) that appear scaly and flake off over time. Dead keratinocytes release a protein substance called defensins. The immune system's first line of defense consists of these cells.
Let’s review the players (cells) in the epidermis
Keratinocytes
Keratinocytes reside primarily in this layer and are born in the basele sheet. The primary functions of these cells are to produce keratin and release fats to create the skin's water barrier. These players help regulate calcium metabolism via the initiation process to make vitamin D from UVB light.
Metanocytes
They produce melanin within the basele layer and are responsible for your skin pigment. Melanin takes a very long time to reach the outer skin. This compound is a natural sunscreen because UVB light causes melanin to be released, which then protects the skin from UV rays. Another way to produce melanin is through a series of chemical reactions involving the amino acid tyrosine.
Langerhans’ cells
Cells like these and dendritic cells make up the skin's primary defense crew. The stratum spinosum is its main residence. Their job is to patrol the epidermis for invaders. After the unwanted visitors are arrested, they are transferred to a lymph node for removal.
Merket cells
They prefer to live in the stratum basale, the basement layer. Merket cells help you identify what you are touching. Their sensors are distributed throughout the fingertips, palms, and soles.
Second at bat is the Dermis region:
Dermis is below the epidermis and has only two layers: papillary and reticular. They serve as the blueprint for constructing, supporting, and protecting other tissues. Unlike the epidermis, the papillary layer has a more flexible connective tissue. Reticulating layers are thicker and denser due to collagen fiber bundles. The dermis region houses sweat glands, hair follicles, muscles, and blood vessels, among other organs.
Last at bat is the Hypodermis region:
Known as subcutaneous fascia, this region is the shallowest of the three. Here, fat cells occupy the majority of the space. They resemble marshmallows spread out on this region's floor. A few hair follicles, sensors, and blood vessels are also located here.
I would like to take an intermission and we will reconvene next week. The time has come for me to recharge, and I'm assuming you feel the same way. By digesting this information, you will be more prepared for next week's Script. Until next time, Stay Strong & Stay Vivid!
Reference:
1. Yousef H, Alhajj M, Sharma S. Anatomy, Skin (Integument), Epidermis. [Updated 2021 Nov 19]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-.
2. Skowron. K. et al. (2021). Human Skin Microbiome: Impact of Intrinsic and Extrinsic Factors on Skin Microbiota. MDPI. h https://doi.org/10.3390/microorganisms9030543.
3. Ratanapokasatit. Y. et al. (2022). How Microbiomes Affect Skin Aging: The Updated Evidence and Current Perspectives. MDPI. https://doi.org/10.3390/life12070936.
4. De Pessemier. B. et al. (2021). Gut-Skin Axis: Current Knowledge of the Interrelationship between Microbial Dysbiosis and Skin Conditions. MDPI. https://doi.org/10.3390/microorganisms9020353.
5. Gürtler. A. et Schmitt. L. (2021). The impact of clinical nutrition on inflammatory skin diseases. Wiley. https://doi.org/10.1111/ddg.14683.
