Vie et mort de la peau : comment les cellules se renouvellent-elles ? - MyPureSkin

Life and death of the skin: how do cells renew themselves?

If the expression “get a new look” is sometimes used in a figurative sense, it is a phrase perfectly adapted to the daily reality of any human being.

Constantly producing new cells, your skin envelope is in fact the seat of a multitude of biochemical reactions involving complex metabolic mechanisms but which are absolutely necessary to preserve the health of your skin.

Birth, development and destruction: discover some astonishing details about the life cycle of your cells but also and above all how to take care of them so that your epidermis can continue to shine each time you “get a new skin”.

Environment and genetic predispositions: the hectic life of your skin cells

Skin cells are called “differentiated” (or specialized) in the sense that their roles in the body are very distinct.

It is this differentiation that makes the different functions of the human body possible.

The natural process of differentiation therefore consists of transforming stem cells (undifferentiated) into different and specialized cells which will make up organs such as the heart, the digestive system or even the skin.

For your body to develop healthily, this process follows the construction plan coded in your genetic heritage. However, the environment can influence this differentiation to give different results from one individual to another.

cell division

This is particularly the reason why “identical” twins with distinct living conditions may have drastically different physical characteristics as they age.

From the point of view of the skin, this means for example that even if an individual has genetic predispositions to a certain dryness of the skin, it is possible to avoid excessive loss of hydration by limiting the expression of certain genes by control of their living environment.

Prolonged and frequent exposure to the sun, to air pollutants such as cigarette smoke or an unbalanced diet over the long term are therefore “epigenetic” factors in the evolution of your skin phenotype.

In other words: these elements can impact the way in which the genes defining the characteristics of your skin are expressed, as shown in a study ¹ conducted by researcher Lavinia Arseni in 2018.

By understanding the role of the most important epigenetic factors at key stages of its life, such as cellular differentiation, it becomes possible to prevent the risks of premature aging and limit your chances of seeing dysfunctions emerge in your skin organ.

In this regard, the scientific community very quickly understood that food plays a major role.

From the basal layer to the stratum corneum: nutrition to differentiate yourself

The epidermis contains several types of cells, two of which contribute to its most visible characteristics to the naked eye:

  • Melanocytes (mainly responsible for its pigmentation);
  • Keratinocytes (largely responsible for its mechanical resistance and impermeability);

structure of the epidermis

The texture we perceive of our skin, its resistance and its appearance are largely dictated by dead keratinocyte cells, of a particular kind: corneocytes. These cells form the most superficial layer of the epidermis: the stratum corneum.

However, before dying and joining this layer, keratinocytes are born and develop by gradually migrating from the inside to the outside of the skin.

This birth, this growth, this life cycle in short is impossible without the nutrients that our food provides us.

Understand why and how to better nourish your skin

To determine the best way to nourish yourself, it is essential to first understand the key players in your skin's outward signs of health.

Whatever your phenotype, three factors visible to the naked eye are generally used to determine the health of your skin:

  • Its elasticity;
  • Its firmness;
  • Its texture.

There are 4 skin types that represent common combinations of values ​​for these three factors:

  • Oily skin;
  • Combination skin;
  • Normal skin;
  • Dry skin.

Your genetic makeup determines your skin type and unless it is naturally soft, smooth and with few or no visible imperfections, that type is not categorized as “normal”.

If this is your case, epigenetic factors, including diet, are of great importance in maintaining the health of your skin. For example, we would say that dry skin is less healthy than visibly “normally” hydrated skin.

To remedy this, an adjustment to your diet or even (most often) the combination of a local nutrition solution (cream) and general nutrition (food supplement) represent your best chances.

But how can these solutions help? What mechanisms lead it to such a state and what elements justify the use of such products?

Skin architecture: a universe in perpetual motion

Before reaching the stratum corneum, the journey of keratinocytes begins in the basal layer of the epidermis, that is to say the deepest layer.

Resting on the basal lamina (interface between the epidermis and the dermis which ensures the transmission of nutrients from the dermis), the stem cells occupy the role of cell production.

Langerhans cells (immune role), Merkel cells (sensory role), melanocyte (pigmentary role) and keratinocytes (mechanical role) are all cell types differentiated from basal layer stem cells.

layers of the epidermis

It is because the latter continuously create cells that the keratinocytes produced find themselves “pushed” outwards.

This rise towards the stratum corneum causes them to gradually change their composition and shape to fulfill different roles along the way, passing through 4 epidermal layers in total:

  • The basal layer (where they are born);
  • The spinous layer (where keratinocytes begin the concentration of keratin precursors);
  • The granular layer (where keratinocytes begin to contain keratin and accumulate it to prepare to compose the waterproof armor that represents the stratum corneum);
  • The stratum corneum (which the keratinocytes reach after having torn on the way, thus emptying themselves of their contents, notably keratin, to flatten themselves).

It takes on average 28 days for newly born keranocytes to reach the stratum corneum. This is why we commonly say that we get a makeover every month.

The extracellular matrix of the dermis: where it all begins

However, the genesis of keratinocytes and other cells of the epidermis by stem cells could not be achieved without a certain raw material.

This is the reason why the dermis, underlying the basal layer of the epidermis, brings together cells specialized in the production of key elements to allow nutrients to circulate between cells horizontally and vertically. : these are fibroblasts.

True production units, fibroblasts carry out the synthesis of the components of the extracellular matrix (ECM), which they expel through their membrane.

extracellular matrix

It is in the ECM that the cells of the dermis are mainly bathed and it is therefore through which amino acids, vitamins and trace elements pass allowing them to have the energy and materials necessary to maintain their functions. .

In addition, a sufficiently nourished ECM is essential to allow the skin to maintain its macroscopic properties.

State of health of your dermis and macroscopic consequences

Indeed, if the superficial mechanical resistance and impermeability of your skin is provided by the epidermis, it is the dermis which allows it to be both supple and elastic.

To be exact, it is the ECM which is in charge of these two properties by being composed in sufficient proportions of the fruits of the metabolic activity of fibroblasts, that is to say mainly:

  • Collagen;
  • Hyaluronic acid;
  • Elastin.

The active ingredients of nutricosmetics: a way to support skin aging

Offering good resistance to traction because it is not very flexible, collagen is what allows you to maintain firm skin (as opposed to elastin which allows your skin to be, so to speak… elastic).

For its part, the hyaluronic acid in your ECM allows it to store water that can be called upon according to the metabolic needs of your fibroblasts.

Unfortunately, from the age of 20, your fibroblasts slow down the production of these two essential ingredients for maintaining the quality of your skin. The consequence is progressive but visible: your skin loses firmness and ends up changing its type. In fact, over the years it tends to be less “normal” and drier.

This is the reason why any quality food supplement cannot do without the now well-known duo of collagen and hyaluronic acid.

By combining these two active ingredients, nutricosmetics aims to support the aging process by preventing this loss of “productivity” from being too sudden in order to reduce fine lines and wrinkles.

Take nutrients already present in your skin as active ingredients

However, the most effective food supplements on the market go even further. By integrating other elements involved in the life cycle of the epidermis into their formula, some seek to offer quickly visible results for long-term action.

It is with this in mind that ceramide is found in certain nutricosmetics.

In a study published in 2009 2 , researcher Yukiko Mizutani is interested in the role of ceramides in the epidermis and its biosynthesis by keratinocyte cells. In particular, we discover that oral ceramide supplementation makes it possible to improve the effectiveness of the barrier function of the epidermis as well as its permeability characteristics.

Vitamin C, vitamin E, zinc… numerous active ingredients are selected to support your skin in its metabolic functions.

Nutritional synergy: when the whole is more than the sum of its parts

What the expertise of nutricosmetic engineering has made it possible to discover, however, goes beyond a simple combination of elements with individual beauty benefits.

By combining organic silicon with collagen, for example, Doctor Lidiane Advincula de Araújo was able to conclude in a 2016 study³ that it was possible to optimize the production of collagen in fibroblasts.

In the same way, we know from key work such as that of Doctor Nicholas N. DePhillipo in 2018 (see source 4) , that vitamin C supplementation also improves the synthesis of collagen by the body, in addition of the increased antioxidant protection it confers.

All these discoveries demonstrate that your skin and more generally your body are the site of biochemical reactions occurring constantly to allow you to maintain good health and that it is possible to take advantage of this understanding to take advantage of a key concept: synergy.

MyCollagenlift: a synergistic cocktail of premium quality ingredients

It is thanks to its expertise that the MyPureSkin laboratory team was able to select entirely natural and premium quality ingredients in order to combine them in an exclusive formula: that of the MyCollagenLift food supplement, capable of supporting the aging process of your epidermis and dermis.

The result of an intimate understanding of the mechanisms of senescence in your skin, MyCollagenLift is a targeted nutrition solution capable of being integrated into your daily health routine to help your skin organ remain the best version of itself.

Indeed, MyCollagenLift is:

  • Marine collagen peptides whose molecular weight allows them to be very bioavailable (i.e. easier to assimilate by your body);
  • Hyaluronic acid to help you achieve a good level of hydration;
  • Wheat oil ceramides to complete this hydration-maintaining effort for your skin;
  • Vitamin C from acerola fruit helping to protect your cells from oxidative stress;
  • Vitamin E also acting as an antioxidant;
  • Organic silicon used to structure your skin while increasing your defenses against the harmful effect of free electrons.

Convinced of the importance of nourishing your body to get new skin in good conditions? Want to take care of your epidermis and dermis to regain normal skin? MyCollagenLift supports you in your first 3-month treatment for visible results from 4 weeks!

  1. Study by the Arseni team evaluating the impact of collagen alterations on health:
  2. Publication by researcher Yukiko Mizutani on the role of ceramides in the skin and their synthesis by keratinocytes:
  3. Lidiane Advincula de Araújo's team is researching the effects of silicon supplementation on collagen production:
  4. Study by Nicholas N. DePhillipo on the effectiveness of vitamin C in stimulating collagen synthesis: