The structure of the skin on the face is similar to the structure of the skin at any other part of the body.

The skin on the face consists of the same structures: epidermis, dermis and subcutaneous fiber. It participates in thermoregulation, protects against penetration of microbes and from negative environmental factors.

The human skin is capable of performing these difficult functions thanks to a three-layer structure in which each layer performs its tasks.

The outer layer of human skin is called the epidermis. It is he who carries the main burden on the protection of the body from external factors.

The long-term and more active is influence, the thickness becomes the epidermis, so people, most of the day spent in the open air, the structure of the epidermis changes.

Externally, this is manifested as a degradation and thickening of the skin of the face. Strong ultraviolet irradiation also leads to changes in the structure of the epidermis.

The building of the epidermis provides the process of continuously updating skin cells. The lower layer consists of a special germinal tissue, so it is called basal (translated from the Greek - "base").

The basal layer is the basis of constant skin renewal. It forms new cells instead of the dead.

Binding at the base of the epidermis, young, while still small cells begin to grow and move up.

For 3-4 weeks, they reach the outer border of the skin, where they are quickly dying, dry, and from them a horny layer or epithelium is formed, protecting the underlying tissues from the external environment.

The special structure of the horn layer allows him to perform his functions well - protect live cells from evaporation of water from them.

It consists of shells of dead cells, bonded with each other like fishing scales. But gradually, dead cells are exfoliated, and in their place there are new, while still alive.

Man's skin renewal is so largely that if we consider in the microscope the structure of dust accumulating in the apartment, it turns out that it is most of the scales of the horn layer.

In the building of the epidermis, an important place occupies an intercellular substance.

It is:

1. fatty acid;
2. ceramides;
3. cholesterol.

All these substances are necessary for the skin in good condition. The lack of each of them leads to cosmetic issues. For example, with a shortage of ceramides begins peeling of the face.

Considering the structure of the epidermis, it can be noted that there are no blood and nervous paths in it.

The capillaries are only suitable for a basal layer, and the network from large vessels is located below the epidermis.

This feature of the building of the epidermis affects the complexion. The higher the grid of the vessels is located, the skin will be rose, and the pale skin means that the epidermis of nature is thickened and the vessels pass deeply.

The structure of nervous and blood circuits is similar. The nerves go parallel to the blood vessels, and free nerve endings ending with the level of the last capillaries are suitable for the lower border of the epidermis. Nerves bind the skin of the face with the brain and the rest of the authorities.

The structure of the dermis

Under the epidermis lies the next layer of skin of the face - Derma. Its structure is also inhomogeneously.

In the upper part there are sebaceous glands, which, together with sweat, provide the creation of a film consisting of a special water-fat emulsion on the surface of the skin.

This mantle protects the face from the penetration of microorganisms.

The dermis top covers the membrane layer. Its dense and solid building allows him to serve as a support for the epidermis.

Below the membrane layer is a loose puffy cloth. Pacifics increase the area of \u200b\u200bcontact of the dermis and epidermis.

The main place in the structure of the dermis takes the mesh layer. It consists of powerful collagen fibers and plays the role of support for the top layer of the skin.

There is an amorphous substance between the fibers, which produces special structures of the dermis - fibrocytes consisting of fibroblast cells. Collagen and elastin are also formed in fibrocytes.

The amorphous substance, the filling gaps between collagen fibers, consists mainly of hyaluronic acid.

In cosmetology, learned to artificially introduce hyaluronic acid, when its number in the face of the face decreases. This procedure is called biorevitalization.

The production of hyaluronic acid decreases with age or as a result of long-term illness. Its disadvantage immediately affects the condition of the skin of the face.

Innovative technology in cosmetology - biorevitalization - helps to some extent to cope with this problem and slow down the appearance of signs of aging.

It has been proven that the work of fibrocytes is accelerated by improving physical exertion. From this we can conclude that the dermis is elastic and filled, and the skin has not saved, the person should move more.

So, the functions of the demes are as follows:

1. thermoregulation due to changes in blood flow rate in capillaries and sweating through sweat glands;
2. protection of the underlying and depreciation of the overlying structures that the dense mesh is provided with elastic collagen fibers;
3. ensuring the sensitivity of the skin of the face due to the numerous nerve fibers located in the dermis.

There is nothing complicated in the building of the dermis. Tens of well-known laboratories are engaged in the study of its structure and possibilities to influence it using cosmetics.

This layer is paid so close attention due to the fact that it is from its condition, the right structure and the level of moisture depends on a good appearance of human skin.

The structure of subcutaneous fatty fiber

The third layer of the skin is called hypoderma or subcutaneous fatty fiber. It consists of connecting and fat cells. It is the hypoderma that gives the person a man in childhood and youth.

With age, its layer decreases, the face loses the volume and slowly "slides" down.

The thickness of the hypoderma depends on which part of the human body it is located. The worst fat layer is located in the abdomen, buttocks and hips.

On the person of a person, the impressive layer of the hypoderma is located in the area of \u200b\u200bthe cheek. The area around the eyes is almost devoid of a fat layer, so it is careful with the help of special means.

Hydrometer is an energy battery, protection from heat, cold and shocks. She softens the fall, delays warmly inside the tissue and does not miss the heat and cold from the external environment to the internal organs.

In subcutaneous fatty tissue there is a stock of fat-soluble vitamins (A, E, F, K).

In general, we can say that the smaller the fatty fiber face, the more wrinkles on it. The skin of the face with a relaxed hypoderma rather aggravated, fasterly covered with folds and wrinkles.

The function of fatty fiber includes synthesis and accumulation of female hormones - estrogen. The thicker layer of the hypoderma, the greater the estrogen body.

It is dangerous for a strong floor, since the increase in estrogen leads to suppressing the production of male hormones.

Hydrometer is responsible for the feeling of satiety. It has a hormone leptin, responsible for the emergence of this feeling.

In addition, Leptin regulates the thickness of the hypoderma and the percentage of fat in it.

Unfortunately, with age, some of the cells of the hypoderma simply "burns", and it is impossible to restore the structure and thickness of the subcutaneous fatty fiber layer.

The skin is the largest human body body having a complex structure and performing a number of vital functions. This is the most open and unprotected part of the human body, especially it concerns the skin on the face. In the state of the skin, as in the mirror, not only unfavorable external factors, but also age, diet, bad habits are reflected. Therefore, our main task is carefully and systematically, and not from time to time to take care of it. In order for skin care, it should be reasonable and competent, first of all, you should get acquainted with its structure and functions, as well as learn how to define your skin type.

Three layers of skin are distinguished, the total thickness of which is only a few millimeters. All of them are pierced by a variety of blood vessels, nerve fibers, sebaceous and sweat glands, hair lows.

So, the outer layer, or epidermisform layers of epithelial cells that lie on each other. The top layer, or the so-called horny layer, directly interacts with external factors. It consists of burritable cells that rise to the surface of the skin from the deep layers, thereby freeing the place for young cells. The horny layer protects our body from penetrating inside microbes and foreign substances, and also delays moisture. Hydro-lipid protective mantle helps him. It is a thin film located on the surface of the skin. It consists of sweat particles, the selection of sebaceous glands and viscous substances connecting individual oroging cells. This is a kind of natural skin cream with an acidic chemical medium that kills fungi and bacteria.

The epidermis is also responsible for the occurrence of a tan, since in its deepest layer with special cells - melanocytes - the pigment of melanin is produced. It regulates tanning intensity and skin color. The amount of melanin depends on the degree of exposure to ultraviolet rays, as well as on the genetic predisposition of the body. The number of melanocytes is approximately the same in all people.

Under the epidermis is located dermis, or actually leather. It includes two layers: puffy and mesh. Their total thickness is approximately 2-2.5 mm. This is a kind of skin frame, supporting its elasticity due to collagen and elastin fibers. The main difference between the layers of the dermis is the structure of the fibers. In the nipple layer, they are thinner and moving, and in the mesh - more dense. Collagen fibers give the skin strength and have the ability to update. But the elastin fibers that are responsible for the elasticity of the skin are not restored, which leads to the appearance of wrinkles and flabbiness of the skin. The space between the fibers is filled with water gel. This viscous substance, most of which is hyaluronic acid.

It should be remembered that the fibers have a certain direction. Therefore, during facial care procedures, in particular, when applying a cream or massage, it is necessary to strictly follow massage lines. This will help to avoid premature loss of elasticity of fibers, and therefore premature aging of the skin.

The mesh layer also contains greasy, sweat glands and hair onions. The selection of sebaceous and sweat glands create additional protection against microorganisms. However, this protective film is easily destroyed using alkaline tools, such as soap. Therefore, clean the skin is better using special means, effectively removing pollution and at the same time do not wash off the natural acidic barrier of the skin.

The dermal, unlike the epidermis, is pierced by nerve endings, muscles and receptors. It has both blood vessels that carry nutrients and oxygen to the top layer of the skin and give it a pleasant pink shade.

The third, the deepest layer of the skin is hypodermis, or subcutaneous fatty fiber. It is a connecting fabric consisting of cells - fat cells. Immediately under it is a muscular layer.

Hydrometer performs three main functions:

❧ prevents internal organs from damage;

❧ helps to regulate body temperature,

❧ protecting it from overheating and supercooling; Makes the skin smooth and soft.

The thickness of the adhesive layer in all women is unequal and depends on the genetic predisposition, and on the lifestyle. It is worth noting that the hypoderma is practically absent on the lips, it is not at all on the centuries. Therefore, these sections of faces need particularly careful care.

Search by book ← + ctrl + →
Part I. General PartCell elements of dermis

Chapter 1. Anatomy and histology (cellular structure) of the skin. Features of the anatomy and histology of the skin in children

Being an external cover of a person's body, the skin has a complex structure and performs several important functions. The largest human body is the skin. Square area depends on age, weight and human growth and is 1.5-2 m 2. The weight of the skin is about 4-6% of the total body weight, and if we take into account the subcutaneous fat tissue, then 15-17%. The total number of skin cells is 9-12 billion, i.e. 6 million / cm 2. Skin thickness depends on age, skin color, gender, health and localization states. At different parts of the body, the skin has a different thickness: from 2.12 to 11.57 mm in men and from 2.07 to 10.4 mm in women (Table 1).

Table 1

The thickness of various layers of the skin of an adult (in millimeters)

The elderly and children are skin thinner than an adult. In the children of the first months of life, the average is 1 mm; aged 3 to 7 years old - 1-1.5 mm; From 7 to 14 years - 1.5-2 mm and only by 20-25 years it reaches 3 mm.

The skin in the natural holes (nose, mouth, the vagina, the rear pass, the urethra) goes into the mucous membrane.

The skin consists of 3 layers:

1) upper - epidermal or epidermis;

2) actually leather or dermis;

3) subcutaneous fatty fiber.

Epidermis Presents multi-layer flat ornamental epithelium. Due to the ability to energizing, or keratinization, the main cell element of the epithelium is called keratinocyte. In the epidermis, five cell layers are distinguished, each of which is a certain stage of differentiation (development) of keratinocytes.

The deepest layer - basal, or germ layer , borders with a derma and consists of one row of cells. In the cytoplasm of keratinocyte, i.e. intracellular, there are dark brown or black pigment granules - melanin. In the lateral people, the pygment melanin is only in the cells of the basal layer. The dark-skinned persons are also found in the cells of the hipged layer, and in the horn layer. Melanocites are also located in the basal layer, which make up about 10-25% of the base layer cells and produce a pigment melanin. The ratio of melanocytes to keratinocytes in the epidermis is 1: 36. Black people and representatives of the white race, the number of melanocytes is approximately the same. Melanin participates in the processes of wound healing and protects the cells of the body from the damaging effects of ultraviolet radiation.

Among the basal (basic) keratinocytes there are tactile cells - Merkel cells (Merekel wheels). Especially many Merkel cells in the basal layer at the tips of the fingers, lips. Langerhans and Greensyne cells, or immune, together participate in the regulation of immune reactions in the skin. Langergans cells are capable of phagocytosis: exciting alien antigens and holding them on the surface, they provide immunological memory. Langerhans cells can synthesize biologically active substances: γ-interferon, interleukin-1, etc. Langerhans cells are distinguished by meth-enkefalin - an endogenous modulator (internal pathogen) of pain and a strong immune system stimulator. Above the basal layer is a hipped layer. Then there is a granular layer. On the palms and soles, the grainy layer consists of 3-4 rows, on other sections this layer is presented with 1-2 rows of cells. The grain layer cells lost the ability to share.

Flattened, nuclear-free keratinocytes form brilliant layer consisting of 3-4 cell rows. The brilliant layer is clearly visible on the skin of the palms, where the thick epithelium. The cells of the shiny layer contain eleidine, glycogen, oleic acid. The boundaries of the shiny layer cells are visible bad.

Non-surfactant outdoor part of the epidermis is horny layer . The thick horny layer on the skin of the palms and soles, on the extensitive surface of the limbs. A more subtle - horny layer on the stomach, on the bending surface of the limbs, on the side surfaces of the body, especially thin on the skin of the eyelids and the external genital organs in men. The horny layer is represented by horny plates (scales, cornocytes) - cells located at the final stage of keratinization (oroging). The horny plates in the outer part of the epidermis are gradually discharged. This process is called the desquamation of the epithelium. Horn scales are two types: with loose and dense filling of keratin fibrils (fibers). Loose horny flakes are located closer to the grain layer, they can detect the remains of cellular structures (mitochondria, etc.); These scales are called T-cells. Dense horny flakes are surficial. The thickness of the horn layer depends:

1) on the reproduction rate and advancement in the vertical direction of keratinocytes;

2) From the speed of their rejection.

The entire process of skin renewal, i.e. the appearance, differentiation, ripening of keratinocyte, takes about 26-27 days. The main characteristics of the epidermis are shown in Table 2.

table 2

The main characteristics of the epidermis

The structure of the skin as a holistic unit consists of:

1) from epidermal vertical cell columns providing gradual growth and replacement of the upper layer of skin adequately corresponding to external environmental impacts and the internal needs of the body;

2) from the dermo-epidermal compound;

3) actually dermis;

4) subcutaneous fatty fiber.

Dermat-epidermal connection. The border between the epidermis and the dermis is a wavy line of complex shape. The epidermis is attached to the derma using the basal plate, or the membrane.

The dermis consists of fibrous connective tissue (cellular elements and extracellular matrix). The thickness of the dermis is different: on the back, the fastest thighs and chest; In the skin of the exterior genital organs, palms and soles are thinner. Two layers of clear boundaries are distinguished in the dermis:

1) subepitial, or papilla;

2) Mesh.

The puffing layer goes into the epithelium in the form of nipples, which causes the presence of small furrows on the surface of the skin forming a unique skin pattern. Pauses and mesh layers of dermis are formed:

a) various cells (histiocytes, fibrocytes, fibroblasts, fat cells or labrocytes, plasma cells, etc.), which are less in the derma than in the epidermis;

b) extracellular matrix (basis) in which polysaccharides and fibrillar proteins are located.

← + Ctrl + →
Part I. General PartCell elements of dermis

Navigation by article

Leather - This is one of the human organs that perform a protective role and a number of biological functions. The skin is covered by the whole body of a person, and depending on growth and weight, its area is from 1.5 to 2 m 2, and the weight of 4 to 6% of the mass of human (excluding hypoderma).

The article discusses the structure of the human skin, its structure and functions of each layer, how the skin cells are formed and updated and how to die.

Skin features

The main purpose of the skin - This is of course protection against external environmental impact. But our skin is multifunctional and complex and takes part in a number of biological processes occurring in the body.

Basic skin functions:

• mechanical protection - The skin prevents soft tissues from mechanical exposure, radiation, microbes and bacteria, ingress of foreign bodies inside the tissues.
• ultraviolet defense - Under the influence of solar cure in the skin, melanin is formed as a protective reaction to an external unfavorable (with long stay in the sun) effect. Melanin causes temporary skin staining in a darker color. A temporary increase in the number of melanin in the skin, increases its ability to delay ultraviolet (delays more than 90% of radiation) and helps to neutralize the free radicals formed in the skin (performs the role of antioxidant).

• temoregulation- participates in the process of maintaining the constant temperature of the whole organism, due to the work of the sweat glands and thermal insulation properties of the layer hydrometerconsisting mainly of adipose tissue.
• tactile sensations - Due to the nerve endings and various kinds of receptors near the skin close to the surface, the person feels the impact of an external environment in the form of tactile sensations (touch), and also perceives changes in temperature.
• maintaining water balance - Through the skin, an organism, if necessary, per day can be isolated up to 3 liters of fluid through sweat glands.
• exchange processes - Through the skin, the body partially removes side products of their livelihoods (urea, acetone, bile pigments, salts, toxic substances, ammonia, etc.). Also, the body is able to absorb some biological elements from the environment (trace elements, vitamins, etc.), including oxygen (2% of the entire body gas exchange).
• synthesis of vitaminD.- Under the influence of ultraviolet radiation (sun), vitamin D is synthesized in the inner layers of the skin, which is later absorbed by the body for its needs.

Skin structure

The skin consists of three main layers:

• epidermis (Epidermis)
• dermis (Corium)
• hypodermis (Subcutis) or subcutaneous fatty fiber

In turn, each layer of skin consists of its individual structures and cells. Consider the structure of each layer in more detail.

Epidermis

Epidermis - This is the top layer of the skin, formed mainly based on keratin protein and consisting of five layers:

• horny - the topmost layer, consists of several layers of epithelium orinal cells, called corneocytes (horny plates), which contain insoluble keratin protein
• brilliant - consists of 3-4 rows of cells elongated in shape, with a circuit of an incorrect geometric shape containing eleuidin, from which in the future is formed keratin
• grainy- consists of 2-3 rows of cylindrical or cubic cells, and closer to the surface of the skin - rhombid
• spikeful - consists of 3-6 rows sophisticated keratinocytes, polygonal form
• basal - the lowest layer of epidermis, consists of 1 row of cells called basal keratinocytesand having a cylindrical form.

The epidermis does not contain blood vessels, so admission nutrients From the inner layers of the skin to the epidermis occurs Due to diffusion (penetration of one substance to another) tissue (intercellular) liquids from the layer of dermis in layers of epidermis.

Intercellular fluid - This is a mixture of lymph and blood plasma. It fills the space between the cells. In the intercellular space, the tissue fluid falls from the end loop of blood capillaries. There is constant metabolism between the fabric liquid and the circulatory system. Blood delivers nutrients into the intercellular space and removes the products of cells of cells by the lymphatic system.

The thickness of the epidermis is approximately equal to 0.07 - 0.12 mm, which is equal to the thickness of the simple paper sheet.

In some parts of the body, the thickness of the epidermis is slightly thicker and can be up to 2 mm. The most developed horny layer on the palms and soles, much thinner - on the abdomen, bending surfaces of the hands and legs, sides, the skin and genitals.

PH skin acidity is 3.8-5.6.

How is the growth of human skin cells

In the basal layer of the epidermis cell division occurs, their growth and subsequent movement to the outer corneum layer. As the cells are growing and approaching the horn layer, the keratin protein accumulates in it. Cells lose their core and basic organelles, turning into a "bag" filled with keratin. As a result, the cells die, and form the topmost layer of skin from the burned scales. These flakes with time are extended from the surface of the skin and are replaced with new cells.

The whole process from the generation of cells to its exfoliation from the surface of the skin, occupies an average of 2-4 weeks.

Permeability of the skin

The scales of which consists of the topmost layer of the epidermis are called - cornocytes. The scales of the horn layer (cornecitis) are interconnected by lipids consisting of ceramic and phospholipids. Due to the lipid layer, the horny layer is practically not penetrated for aqueous solutions, but solutions based on fat soluble substances are capable of penetrating through it.

Color of the skin

Inside the basal layer there are cells melanocytesthat allocate melanin - The substance from which the skin color depends. Melanin is formed from tyrosine in the presence of copper and vitamin ions, under the control of hormones allocated by the pituitary. The more melanin is contained in the same cell, the darker color of the skin of man. The higher the melanin content in the cell, the better the skin protects against the effects of ultraviolet radiation.

With intensive effects on the skin of ultraviolet radiation, the production of melanin increases sharply, which provides the tan skin.

The impact of cosmetics on the skin

Everything cosmetics and proceduresintended for skin care, act basically only on the top of the skin - epidermis.

Dermis

Dermis - This is an inner layer of skin, a thickness of 0.5 to 5 mm, depending on the body part. Derma consists of living cells, equipped with blood and lymphatic vessels, contains hair follicles, sweat glands, various receptors and nerve endings. The basis of cells in the dermis is fibroplastwhich synthesizes extracellular matrix, including collagen, hyaluronic Acid and Elastin.

The dermis consists of two layers:

• reticulate (Pars Reticularis) - applies to the base of the nobble layer to subcutaneous fatty fiber. Its structure is formed mainly from the beams of thick collagen fiberslocated parallel to the skin surface. The mesh layer contains lymphatic and blood vessels, hair follicles, nervous endings, glands, elastic, collagen and other fibers. This layer provides skin elasticity and elasticity.
• pARS PAPILLARISconsisting of amorphous structuretural substances and thin connective tissue (collagen, elastic and reticular) fibers forming nipples that occur between epithelial crests of spinged cells.

Hydrometer (subcutaneous fatty fiber)

Hypodermis - This is a layer consisting mainly of adipose tissue, which performs the role of heat insulator, preventing the body from temperature drops.

The hypoderma is accumulated by the nutrients necessary for skin cells, including fat-soluble vitamins (A, E, F, K).

The thickness of the hypoderma varies from 2 mm (on the skull) to 10 cm and more (on the buttocks).

With inflammatory processes in the hypoderma arising in the process of certain diseases, cellulite occurs.

Video: Skin structure

• The area of \u200b\u200bthe whole skin of an adult is 1.5 - 2 m 2
• In one square centimeter of the skin, contains:

• more than 6 million cells
• up to 250 glands, of which 200 sweat and 50 sail
• 500 different receptors
• 2 meters of blood capillaries
• up to 20 hair lows

• With an active load or high external temperature, the skin through sweat glands can allocate more than 3 liters of sweat per day
• Thanks to the constant updating of cells, we lose about 10 billion cells per day, this is a continuous process. Throughout life, we drop about 18 kilograms of the skin with oroging cells.

Skin cells and their function

The skin consists of a large number of different cells. To understand the processes occurring in the skin, it is good to have a common idea of \u200b\u200bthe cells themselves. Consider what the various structures are responsible. (Organly) in a cage:

• core cells - Contains hereditary information in the form of DNA molecules. Replication is replicated in the kernel - doubling (reproduction) DNA molecules and synthesis of RNA molecules on the DNA molecule.
• sheath kernel - Provides metabolism between cytoplasm and cell core
• nadryshko cells- It occurs synthesis of ribosomal RNA and Ribosomes

• cytoplasm - Semi-liquid substance that fills the inner space of the cell. Cellular metabolic processes in cytoplasm flow
• ribosomes - are necessary for the synthesis of amino acid proteins on a given matrix based on genetic information laid in RNA (ribonucleic acid)
• vesicle - Small formations (containers) inside the cell in which nutrients are inhibited or transported
• machine (complex) Golgji - This is a complex structure that participates in the synthesis, modifications, accumulation, sorting various substances inside the cell. Also performs the transportation functions synthesized in the cells, through the cell membrane, beyond its limits.
• mitochondria- The energy station of the cell, in which the oxidation of organic compounds and the release of energy during their decay occurs. Generates electrical energy in the human body. An important component of the cell, the change in the activity of which over time leads to the aging of the body.
• lysosomes - need to digest the nutrients inside the cell
• intercellular fluidfilling the space between cells and containing nutrients

»Hyperkeratosis and acne
»Comedogenic cosmetics and acne
»SEMODEX subcutaneous tick
»Propionibacterium Acnes and PropioniBacterium Granulosum Propionibacterium
»Irritated leather and acne
»Heredity and acne
»Food and acne
»Medicines and acne
»Steroids and acne

Types of acne

Read also

Retinoida

Types of retinoids

Read also

Care of eyelashes

Eyelash growth facilities

Prostaglandins for long eyelash growth

List of prostaglandins

We disassemble funds for the growth of eyelashes in the ingredients

Read also

Fighting aging (anti-hay)

Building and basic human skin functions

Man's refreshing period

The skin is a fabric: elastic, porous, durable, waterproof, antibacterial, sensitive, which can maintain a heat balance, to protect against the harmful effects of the external environment, allocate fat, ensure the safety of the skin, produce odorous substances and restore (regenerate), and absorb Some necessary chemical elements and reject others, to protect our organism from the adverse effects of sunlight.

human human skin 3.8-5.6.

There are approximately 5 million hairs on the surface of the skin of a person. On each square centimeter of human skin accounts for an average of 100 pores and 200 receptors.

What layers of skin can cosmetics affect?

Since cosmetic can penetrate deeply (cosmeutic products), whether cosmetics make a dermis?

According to the laws of most countries, a cosmetics can only have an outdoor effect. This means that no cosmetic additives should reach the living layers of the skin and affect them. Cosmetic drugs can and are obliged to interact only with dead skin substances and under any circumstances should not reach its living layers and, moreover, to influence them. This is the purpose of cosmetics.

However, in the lower part of the epidermis there is no "damper" that prevents the penetration of substances into the depths of the dend (in the blood and lymphatic vessels). The presence of effective exchange between the epidermis and the dermis is confirmed by experimental data. Substances overcoming the trans -pidermal barrier, with a certain proportion of probability go to the blood and, in accordance with this, can affect all organism tissues.

What substances are able to penetrate deep into the skin, overcome the trans-pyermal barrier and fall into the dermis?

It has been proven that deep into the skin penetrates: Naital, caffeine, nitroglycerin, essential oils (are enhancers, they are found in the bloodstand), WIT E is delayed at the junction of the epidermis and dermis, the hyilaurion acid 30 minutes after the applique reaches the dermis, and then falls Blood (Source: Journal of Investigative Dermatology). Scientists from the University of Rochester (University of Rochester Medical Center) came to the conclusion that nanoparticles that are part of sunscreen penetrate deep into the skin. Liposomes are nanoparticles that freely penetrate into the deep layers of the skin and deliver the necessary nutrients there.

Skin structure

The secret of an amazing skin multifunction is in its structure. The skin consists of 3 important layers:

• 1. External layer - epidermis,
• 2. Inner layer - Derma,
• 3. Subcutaneous base - hypoderma.

Each layer performs a specific function.

In various parts of the body, the thickness and color of the skin, the number of sweat, sebaceous glands, hair follicles and nerves of unequal.

It is believed that the skin thickness is only a few millimeters, but if the skin constantly needs protection, it becomes thicker, this is a protective mechanism that everyone has. Therefore, in some places, the skin is thicker, in some thinner. The soles and palms have a more dense epidermis and keratin layer.

As for the same hair, there are many hair follicles on the top of the top, and there is no one on the soles. The tips of the fingers and legs contain many nerves and are extremely sensitive to touch.

Manufacturing and properties of human skin: epidermis

The epidermis is the upper horny layer of the skin, which is formed by a multilayer epithelium. In the deep layers of the epidermis cells are alive, there are their division and gradual movement to the outer surface of the skin. The skin cells themselves die and turn into horny scales, which are exfoliated and removed from its surface.

The epidermis is almost impenetrable for water and solutions based on it. Life-soluble substances are better penetrated through the epidermis due to the fact that cell membranes contain a large amount of fats and these substances are "dissolved" in cell membranes.

There are no blood vessels in the epidermis, its nutrition occurs due to the diffusion of the tissue fluid from the subject to the dermis. The intercellular fluid is a mixture of lymph and plasma of blood flowing from finite capillar stakes and returning to the lymphatic and blood system under the influence of heart abbreviations.

What cells are the epidermis?

Most epidermis cells produce keratin. These cells are called keratinocytes (peeled, basal and grainy). Keratinocytes are in constant motion. Young keratinocytes appear in light when dividing germinal cells of the basal membrane, located on the border of the epidermis and dermis. As Keratinocyte matches, it moves to the upper layers, first in a hipped layer, then into the grainy. In this case, keratin is synthesized and accumulated in the cell, especially durable protein.

In the end, keratinocyte loses the kernels and basic organelles and turns into a flat "bag" packed with keratin. From now on, he receives a new name - "cornecit". Corneocytes are flat scales forming the horny layer (toned epidermis cells) responsible for the barrier function of the epidermis.

Cornocyte continues to advance upstairs and, reaching the skin surface, is exfoliated. His place is new. Usually the life path of keratinocyte lasts 2 -4 weeks. As a child, the process of updating the cells of the epidermis is more active, and slows down with age.

Corneocytes are bonded between themselves plastic "cement", consisting of a double layer of special lipids - ceramic (ceramides). Molecules ceramides (ceramides) And phospholipids have hydrophilic "heads" (fragments that loving water) and lipophilic "tailings" (fragments preferring fats).

Melanocytes are located in the basal layer of the skin (basal membrane) and produce melanin. These are cells that produce a pigment melanin, giving the skin color. Thanks to melanin, the skin protects a person to a large extent from radiation: infrared rays are completely delayed with skin, ultraviolet only partially. The formation of pigment spots depends on the state of the basal membrane.

There are in the epidermis and special langerhans cellswhich perform the function of protection against foreign bodies and microbes.

What is the thickness of the epidermis?

The thickness of the epidermis is approximately 0.07 - 0.12 millimeters (it is the thickness of a polyethylene film or a paper sheet), especially coarse skin of our body can reach a thickness of 2 mm.

The thickness of the epidermis is heterogeneous: it is different in different places. The fattest epidermis, with a pronounced burner layer is on the soles, slightly thinner - on the palms, even thinner - on the genitals and the skin of the eyelids.

For how many days is the full update of the epidermis?

The appearance of the skin, its freshness and color depends on the state of the epidermis. The epidermis consists of dead cells, new ones come to replace new ones. Thanks to the constant updating of cells, we lose about 10 billion cells per day, this is a continuous process. Throughout life, we discard about 18 kilograms of skin with oroging cells.

When the skin is exfoliated, it is cleared - this is the necessary process of refreshing the skin, in which all the substances are removed together with dead cells: the cells are removed from dust, microbes, substances released by sweating glands (along with then the urea, acetone, bile Pigments, salts, toxic substances, ammonia, etc.). and much more. The skin does not give the army of microbes to get to us: during the day our skin is attacked by 1 cm from 100 thousand, up to several millions of all sorts of microbes. However, if the skin is healthy, it becomes impermeable for them.

The younger skin and healthier, the more intense the process of its update takes place. New cells pushed old, old are washed off after we take shower, wash, sleep, wear clothes. With age, the cell update occurs more and less often, the skin begins to grow old, wrinkles appear.

The epidermis derma is separated by the basal membrane (it consists of elastin and collagen fibers) with a spike layer of continuously dividing cells, which are gradually moving from the basal membrane to the surface of the skin, where they are brushing and disappearing. The entire epidermis is updated with the entirely replaced by a completely new layer: the mole remains a birthmark, the snaps remain a holes, freckles in freckles, cells with accuracy at the genetic level reproduce, as the skin should look like in accordance with the individual characteristics of each particular person.

The process of movement of cells from the basal membrane to the plums and disappearing from the surface of the skin at a young age is 21-28 days, and then happening less and less. Starting from about 25 years of age, the skin renewal process becomes slower and increases to 35-45 days to 40th and 56-72 days after a 50-year boundary. This is the reason for the use of anti-aging and reducing drugs in a period of at least a month, and for more mature age - at least 2-3 months.

The process of dividing and promoting the cells of mature skin is not only slowed down, but also inhomogeneous on different squabors, which also affects the aesthetic Vij skin. If the leather cleansing cells are layered, the cell division process occurs more slowly, which leads to a more rapid aging of the skin. In addition, the layering of dead cells complicates the penetration of oxygen and nutrients into the skin.

How many layers contains epidermis?

The epidermis consists of 12-15 layers of the horn layer. However, depending on the building, the epidermis can be divided into five main zones (layers): basal, hipgy, grainy, brilliant and horny. The upper (outer) layer of the epidermis consists of already dead cells without nuclei, internal - from living cells that are still capable of dividing.

Fragments of a horn, brilliant and granular layers that do not have the ability to divide can be attributed to dead skin structures, and, accordingly, the boundary between "live and dead" substances should be located somewhere in a thorough-shaped layer.

1. Basal layer of epidermis (sprout)

The basal layer is the most approximate to the dermal inner layer of the epidermis. It consists of a prismatic single-row epithelium and a large number of elopal spaces.

The bulk of the cells here is keratinocytes containing chromatin and melanin.

Basal keratinocytes are located melanocytes containing a huge amount of melanin. Melanin is formed in these cells from tyrosine in the presence of copper ions. Regulates this process melanocystimulating hormone of pituitary gland, as well as catecholamines: adrenaline and norepinephrine; thyroxine, triiodothyronine and androgens. The synthesis of melatonin increases with the action on the skin of the ultraviolet. A considerable role in the synthesis of melanin is played by Vitamin C.

Among the cells of the basal epithelium there are some specific tactile cells (Merkel). They are larger than keratinocytes in size, contain osmophilic granules.

The basal layer ensures the attachment of the epidermis to the leather, and contains the cambial epithelial elements.

2. Spinish layer of epidermis (Stratum Spinosum)

Above the basal layer is a spinous (Stratum Spinosum). In this layer, keratinocytes are located in several layers.

The cells of the hipged layer are large, the form of them is incorrect, gradually becoming flattened when approaching the grain layer. The cells of the hipged layer contain spies in the places of intercellular contacts.

In the cytoplasm of hipged cells there are keratinosomes - granules containing lidides - ceramides. The cells of the hipged layer are isolated outwards of ceramides, which, in turn, fill the space between the cells in the above layers. Thus, a multi-layered flat ornamental epithelium becomes impenetrable for various substances.

In addition, the desplaomoms are also available here - specialized cell structures.

Keratinocytes in a hip-layer contain very little chromatin, so they are more pale. They have one feature: in their cytoplasm there are many special thin tonophybrilles.

3. Granular layer of epidermis (Stratum Granulosum)

Grainy (keratogial) layer (Stratum Granulosum) consists of peeled keratinocytes and processproof epidermocytes. It is assumed that these cells are "wandering" epidermal macrophages performing a protective function.

In the grain layer there are from 1-3 palms and 5-7 on the soles of layers of flat cells, closely adjacent to each other. Their oval cores are poor chromatin. The feature of the cells of the grain layer is peculiar grains in their cytoplasm, consisting of a substance close to the structure to DNA.

There are two main types of granules in the cytoplasm of the grain layer cells: keratoglyanovye and lamellar. The first is necessary for the formation of keratin, and the second ensure the moisture resistance of the skin by discharge of special lipid molecules onto its surface.

4. Brilliant (Eleidine, transparent) layer of epidermis (Stratum Lucidum)

The brilliant layer (Stratum Lucidum) is above grainy. This layer is thin enough, and it is clearly visible only in those areas where the epidermis is most expressed - on the skin of the palm and soles.

It is not on all sections of the skin, but only where the thickness of the epidermis is significant (palms and soles), and is completely absent on the face. Consists of 1-3 rows of flat cells, most of which do not contain nuclei.

Flat, homogeneous keratinocytes are the main cell elements of this layer. The brilliant layer is inherently transitional from living epithelial cells to burritable scales located on the surface of human skin itself.

5. Horny layer of epidermis (Stratum Corneum)

The horny layer (Stratum Corneum) is directly in contact with the external medium of the epidermis layer.

Its thickness varies on different areas of the skin, and quite significantly. The most developed horny layer on the palms and soles, much thinner - on the abdomen, bending surfaces of the hands and legs, sides, the skin and genitals.

The horny layer has only thin nuclear cells, tightly adjacent to each other. Horn scales consist of keratin - albuminoid substances, in excess of sulfur-containing sulfur, but there is little water. The scales of the horn layer are tightly connected to each other and provide a mechanical barrier for microorganisms.

The structure and properties of human skin: Derma

The dermis is an inner layer of skin whose thickness ranges from 0.5 to 5 mm, the largest on the back, shoulders, hips.

The derma is the hair follicles (of which the hair grows), as well as the huge amount of thinner blood and lymphatic vessels that provide food, reduce and relax blood vessels allows the skin to hold the heat (thermostat function). In the dermis there are pain and sensitive receptors and nerves (which are branched into all skin layers and are responsible for its sensitivity).

In the dermis, the functional glands of the skin are also located through which the excess of water and salts are removed (separation function): sweat (sweat) and saline (produce the skin). The sebaceous glands produce a necessary amount of sebum, which protects the skin from aggressive external influence: makes skin waterproof, bactericidal (skin fat along with then creates a sour medium on the surface of the skin, which adversely acts on microorganisms). Potion glands help maintain a constant body temperature, not allowing to overheat, cooling the skin by selection of sweat.

How many layers contains a derm?

The dermis includes two layers: it is mesh and puffy layers.

The mesh layer consists of loose connective tissue. This fabric includes extracellular matrix (we will talk about it in more detail below) and cell elements.

The puffing layer goes into the epidermis and forms skin nipples. These nipples create a special unique "drawing" of our skin and are particularly well visible on the pillows of the fingers and soles of our feet. It is the puffy layer that is responsible for "fingerprints"!

The basis of cells in the dermis is a fibroplast, which synthesizes extracellular matrix, including collagen, hyaluronic acid and elastin.

Extracellular matrix, what is it and what is it from?

In the sink of extracellular matrix, two main components include a fibrillating part and matrix.

Fibrillar part - These are the fibers of collagen, elastin, and reticulin, creating a skin frame. Collagen fibers are intertwined with each other, thus creating an elastic network. This network is located almost on the surface of the skin under the epidermis and is a cable, which gives the skin strength, elasticity.

In the facial zone, collagen fibers create a special thick network. Colhagenic fibers in it are so strictly laid and ordered that they form the lines of the smallest stretching. They are known under the name of Langer's lines. They are known to cosmetologists and masseurs: on Langer lines produce face massage and cause any cosmetics. This is done in order not to load the skin, do not stretch it, provoking the formation of wrinkles in this way.

In adolescence, the frame of collagen fibers is durable and able to ensure the mobility and flexibility of the skin, its elasticity and form. Unfortunately our female age is short ...

I really liked the comparison of the skin with the Soviet bed, which is based on a metal grid. The iron springs of the new bed are quickly returned to its original position, but the framework of the frame of the frame starts to sign and soon our bed loses the shape. Our skin also works - young springs (collagen fibers) are perfectly holding a form, but with age they savage and become flabby. What a great mattress we do not styling on the surface, it will not solve our problem.

Matrix (matrix or amorphous component) By its structure resembles a gel and consists of polysaccharides. More famous from polysaccharides are chitosan, algae polysaccharides, hyaluronic acid.

It is the components of the extracellular matrix both amorphous and fibrillary creates skin from the inside. Saccharides themselves do not form fibers, but they fill all the gaps between the connecting cells and the fibers. It is on them that there is intramaneal vehicles of all substances.

As a result, it is the state of the dermis (the water content in the polysaccharide gel, the integrity of collagen fibers, etc.) determines the state of the epidermis and a healthy skin view.

The structure and properties of human skin: hypoderma (subcutaneous fluid fiber)

Hydrometer - the subcutaneous base (fat layer) protects our body from excess heat and cold (allows us to delay heat inside us), performing the function of the thermal insulator, softens the drop from the shock.

Subcutaneous fluid fiber - vitamins

Fat cells are also a depot in which fat-soluble vitamins (A, E, F, K) may remain.

Less fat - more wrinkles

Subcutaneous fatty tissue is very important as a mechanical support for the outer layers of the skin. The skin in which this layer is poorly expressed, it usually has more wrinkles and folds, faster "aging."

The more fat, the more estrogen

An important function of adipose tissue is a hormone-producing. Fat fabric is able to accumulate estrogens and can even stimulate their synthesis (production). Thus, you can get into a closed circle: the more subcutaneous fat, the more estrogen is produced. This is especially dangerous for men, since estrogenic hormones suppress them from developing androgen, which can lead to the development of hypogonadism. This leads to a deterioration in the work of the genital glands and leads to a decrease in the development of male sex hormones.

It is very important for us to know that in the cells of the adipose tissue contains a special enzyme - aromatase. It is with its help and the process of estrogen synthesis with a fatty tissue is carried out. Guess where is the most active aromatase? That's right, in the fatty tissue on the hips and buttocks!

What is responsible for our appetite and a sense of saturation?

Our adipose tissue contains another very interesting substance - leptin. Leptin is a unique hormone that is responsible for the emergence of a saturation sense. Leptin allows our body to regulate appetite and through it the amount of fat in the subcutaneous tissue.