Scientific Insights into Causes and Prevention of Skin Aging

What are the causes of skin aging?

What are the causes of skin aging? Skin aging is characterized by the appearance of wrinkles, sagging skin, and thinning skin, and there are many causes for it.

It is generally divided into intrinsic and extrinsic causes. This guide describes the main causes of skin aging and explains the scientific basis of skin aging.

This guide to the aging process will be updated as new discoveries about skin aging emerge.

For a more detailed explanation of skin aging, please refer to Chapters 5 and 6 of my latest textbook, Bowman Cosmetic Dermatology (McGraw Hill 2022).

Anti-aging skin care ingredients target specific processes that cause skin aging. There are many different anti-aging ingredients, and you should choose the one that best suits your skin type.

Take the Quiz

16 Bowman Skin Types

Biological Causes of Skin Aging

There are many cellular processes that cause skin aging. Therefore, treating skin aging can be difficult. There are many metabolic pathways that can be attacked, such as:

Cellular senescence

Autophagy

Free radicals (reactive oxygen species)

Inflammation

Short telomeres

Slower rate at which stem cells produce new cells

Decrease in growth factors

Cells lose the ability to “listen” to growth factors

Changes in gene expression

Increase in destructive enzymes such as matrix metalloproteinases (such as collagenase)

Sirtuin expression

Mitochondrial function

There are many skin care products that can protect your skin from the effects of skin aging. Choose anti-aging skin care products based on your Bowman skin type.

Science of skin aging

Senescent cells cause skin aging. Skin cells (keratinocytes and fibroblasts) go through five different cell stages:

Stem cells

Proliferating cells

Differentiating cells

Senescent cells

Apoptotic cells

Cell senescence and autophagy

Apoptotic cells are “dead skin cells” that cannot survive. They are eliminated through autophagy and other processes that recycle cell components.

Therefore, apoptotic cells are considered harmless to the skin.

However, the more senescent cells there are, the more prone your skin is to wrinkles and aging.

Senescent cells lose their ability to proliferate, and their lysosomes and mitochondria lose their function and autophagy.

(5) Senescent cells are not eliminated from the skin but remain there, contributing to skin aging.

The presence of senescent cells is associated with accelerated aging. The goal of skin regeneration is to reduce the number of senescent cells by increasing autophagy.

Senescent cells develop into the senescence-associated secretory phenotype (SASP), which is considered one of the main causes of skin aging.

SASP cells cause damage and aging by releasing the following substances:

proinflammatory cytokines, matrix metalloproteinases (MMPs), growth factors, chemokines, matrix modeling enzymes, lipids, free radicals, and extracellular vesicles (EVs).

The release of these substances by senescent cells leads to inflammation, the so-called “inflammaging” (9).

This inflammation leads to many problems, such as the loss of collagen, elastin, and extracellular matrix (ECM), which leads to fibroblast compaction, reduced DNA synthesis, and ultimately wrinkles, skin fragility, and thinning.

Autophagy is an important process by which organelles such as lysosomes and mitochondria (6) digest or “eat” themselves.

Autophagy eliminates problematic organelles and cells, such as damaged mitochondria, damaged lysosomes, and senescent cells.

Sirtuins and Skin Aging

Research shows that activation of sirtuin (SIRT-1) can extend lifespan in mammals.

Caloric restriction (10) can also activate sirtuins, which is why intermittent fasting has emerged as an anti-aging strategy. SIRT-1 slows aging and activates autophagy.

How Sirtuins Affect Skin Aging

How Free Radicals Cause Skin Aging

How Do Free Radicals Cause Skin Aging?

Free radicals (1), also known as reactive oxygen species (ROS), are formed when an oxygen molecule loses an electron and has an odd number of electrons remaining.

Oxygen molecules with paired electrons are stable; however, oxygen with unpaired electrons is “reactive” because it seeks out and steals electrons from important components, damaging them. (2)

What causes free radicals?

Free radicals are produced by:

Damaged mitochondria

Inflammation

Normal cellular metabolism

Pollution

Smoking

Ultraviolet light

Normal cellular metabolism can lead to the formation of free radicals. Damaged mitochondria can produce free radicals. This is why it is so important to protect mitochondria with antioxidants.

Free radicals attack DNA, cell proteins, and cell membranes and steal electrons, causing damage to these cell components. This causes inflammation.

Free radicals increase the concentration of:

Inflammatory factors

Transcription factors, such as activator protein (AP)-1

Nuclear factor-κB (NF-κB)

Matrix metalloproteinases (MMPs), such as collagenase, which degrade collagen in the skin

Destructive enzymes and skin aging

A group of destructive enzymes that contribute to skin aging are called matrix metalloproteinases, or MMPs.

MMPs are activated by genes, inflammation, UV radiation, and environmental pollution.

Examples of destructive enzymes that contribute to skin aging include:

Collagenase breaks down collagen.

Elastase breaks down elastin.

Hyaluronidase breaks down hyaluronic acid.

Enzymes that contribute to skin aging.

Short Telomeres and Skin Aging

Telomeres consist of a small, repeating DNA sequence at the end of chromosomes. These control the cell cycle. Telomeres shorten with each cell division.

Shortened telomeres can trigger cellular senescence, which leads to aging. (13) However, the role of telomere shortening in aging is still unclear.

Why are telomeres short? The following factors may play a role in telomere shortening:

Free radicals

Physiological stress

Inflammation

Genes that contribute to skin aging and wrinkling

Studies have provided information about which genes are important for the appearance and function of the skin. However, it is too early to develop skin care products that target genetic defects.

Glass et al. (20) showed that genetic studies on aging are only meaningful if they are conducted on human skin.

Genetic studies in animals and cell cultures have not provided any information about human genes that contribute to aging.

Aged skin shows increased expression of inflammatory genes, cytokines, and proteases.

Genes that contribute to skin aging (21) are associated with:

Cellular metabolism

DNA transcription

Signal transduction

Cell cycle regulation

Epidermal differentiation

Keratin filaments

Keratin envelope proteins

Lipid biosynthesis

Skin barrier integrity

Mitochondrial function

Cytokine production

Immune response

Aging research is still in its early stages, but findings are emerging at an accelerating pace. I will update this guide to the science of skin aging as new discoveries emerge.

However, don’t waste your money on skin care products that claim to attack genes that contribute to skin aging.

It is too early to fully understand which genes anti-aging skin care products should target.

How Inflammation Contributes to Skin Aging

When the skin becomes inflamed, many destructive processes are activated, which is called the inflammatory response.

Free radicals, destructive enzymes such as matrix metalloproteinases, and immune cells cause skin damage in inflamed skin, which can lead to skin aging. Senescent cells also form.

To prevent skin aging, it is important to identify and eliminate the cause of skin inflammation and use anti-inflammatory skin care products to counteract the inflammation.

Using the wrong skin care products can lead to skin inflammation.

Cosmeceutical anti-aging skin care ingredients should combat the cause of skin aging.

Retinoids, growth factors, exosomes, defensins, antioxidants, heparin sulfate, and ascorbic acid are all anti-aging ingredients that can fight the causes of skin aging.

The causes of skin aging are complex. To find the right anti-aging skincare, you should consider your Bowman skin type.

DQH Can I use salicylic acid first and then vitamin C? It’s easy to create a skincare routine, but knowing how to use it is another thing entirely. In most cases, if you’re not getting the desired skin results, it could be due to the layering of conflicting ingredients. So, is it possible that salicylic acid and vitamin C are such ingredients? Or are these active ingredients the duo that’s been missing from your skincare routine? If you want answers, stick around because today we are going to explain the benefits of salicylic acid and vitamin C and how they can be used in your daily life. What are the benefits of salicylic acid for skin? Salicylic acid is one of the most commonly used beta hydroxy acids and is favored by many people with oily, acne-prone skin. This acid is derived from willow bark, and unlike its water-soluble relatives (called alpha-hydroxy acids), salicylic acid is oil-soluble, which means it can penetrate deeper into the lower layers of the skin. Once it reaches the lower layers, it can help unclog pores of excess sebum, dirt, bacteria, debris, and impurities. This results in clearer skin tones and greater definition. Not only does salicylic acid benefit the underlying layers, but the outer surface of the skin benefits as well. When applied to the skin, salicylic acid removes the buildup of dead skin cells. This is accomplished by breaking the bonds that hold dead cells to the surface. Over time, this can cause the complexion to look dull and prone to acne, blackheads, and other blemishes. If you’d like to learn more about salicylic acid and how it can improve your skin, check out this dedicated blog post from a beauty insider. What are the benefits of vitamin C for skin? Vitamin C is considered one of the most powerful antioxidants, which means it is very effective at fighting free radicals and preventing them from causing further skin damage. Examples of free radicals include pollution, central heating, UV rays and harsh climate. They attack proteins, fats and cell membranes as soon as they come into contact with the skin, causing signs of premature aging such as fine lines and wrinkles as well as hyperpigmentation, flaky patches of skin and loss of elasticity. Many people usually prefer to use vitamin C in their morning routine as this ingredient gives the complexion a radiant glow. You’ll also find that vitamin C can target areas of hyperpigmentation, plumping the skin and reducing the appearance of fine lines and wrinkles. The thing about vitamin C is that there are a lot of outdated studies going back to the 1950s that describe vitamin C as an unstable skin component. Thanks to improvements in modern technology, this is no longer the case as all products now contain a stable form of vitamin C. Visit The Beauty Insider to learn more about vitamin C. So please check out our blog post. Can I use salicylic acid first and then vitamin C? Yes, you absolutely can. In fact, it’s thought that using salicylic acid before using vitamin C ensures it penetrates faster and works faster. This is an efficient way to utilize two power sources, and the reason has to do with pH. For example, the skin’s natural pH is about 4.7, making it slightly acidic. Salicylic acid and vitamin C are also both acidic, and you’ll find that vitamin C is absorbed quickly into the skin. Therefore, using salicylic acid beforehand can increase the acidity of the skin and allow vitamin C to penetrate into the skin faster. While this is considered an effective way to combine two powerful ingredients, you need to be aware of your skin type and how it reacts to certain active ingredients. Even people with perfect, normal skin can experience skin sensitivity and irritation. Therefore, always consult a doctor or dermatologist before using any new products on your skin. It’s also important to follow skin application rules. In this case, you need to use the product correctly to ensure you get the best results for your skin. If you’re not sure what I mean, the basic rule for skin is to start with the thinnest consistency and work your way up to the thickest consistency. This prevents a barrier from forming on the surface, preventing other active ingredients from penetrating the skin. Can I use salicylic acid at night and vitamin C in the morning? Yes, absolutely, this is considered the most effective way to get returns without any adverse side effects. This is because there is enough time between applications to ensure that the skin’s pH levels return to balance. You’ll also find that Vitamin C is rich in antioxidants and is perfect for use in the morning to ensure your skin is protected and looking its healthiest. Due to the small size of salicylic acid molecules, it is an acid that is able to reach the deepest parts of the skin. While this is effective at keeping skin clear, it also increases the risk of irritation and photosensitivity. Therefore, many people prefer to use powerful BHAs in their evening routine without exposure to UV rays, pollution, or harsh weather. Warning: If you avoid using sunscreen every day, none of these ingredients will do what your skin needs. The combination of chemical peels and powerful ingredients increases the risk of further damage to the skin’s surface. Use SPF 50 every day to keep your skin protected and your lipid barrier healthy, even on cloudy days, keeping your skin in top condition.

Related Articles

Ad Blocker Detected