Читать книгу Is it possible to overcome aging? Today and tomorrow cell therapy - Leonid Yu. Prokhorov - Страница 4

With age, changes are occurring in the overall size, shape and composition of the body, soft parts of the face and skin, changes the bone system.

► Skin changes usually begin after 40 years, especially noticeable for the structure of the upper (epidermal) layer, which is thinned and flattened. By the age of 80 its thickness is 25% less than at the age of 30. The relief of the skin pattern on the palms, soles and fingers of hands and feet is smoothed. The changes affect the papillary layer of skin proper (dermis), which also becomes thinner. Gradually atrophy occurs in subcutaneous fat, which in long-livers may eventually disappear completely. Brown pigment spots appearing on the skin are characteristic for the back of the hands, shoulders, chest, etc. (Khrisanfova, 1999).

According to other data, the visible aging of the skin take place from the age of 25 years, when subcutaneous fat tissue begins to becom thin, and the elasticity of collagen structures decreases (Guide to gerontology, 2005).

Due to the decrease in the number of sweat and sebaceous glands the skin becomes drier, its elasticity is lost. In men, the decrease in sebum occurs later than in women. The most obvious signs of aging are wrinkles. With age, there are multiple wrinkles on the skin, especially in open areas, such as the face, for example, the so-called «crow’s feet» at the outer corner of the eye. For fig.1 shows a picture of an elderly European woman, and in fig.2, for comparison, – photo of a young woman. The face ages faster than other parts of the body (Khrisanfova, 1999). This is explained by the fact that the person is more exposed to atmospheric influences, including sunlight, compared to other parts of the body. Aging under the influence of sunlight is called photo aging, since sunlight accelerates skin aging. Especially this process is affected by ultraviolet radiation, as part of the solar spectrum (Molochkov et al., 2005). The exposure to wind, dust, dryness, the action of microorganisms, detergent components, etc. accelerate skin aging.

The skin temperature decreases, especially among long-livers. This is due to a general decrease in metabolic processes, but partly due to the deterioration of blood supply and changes in sweat glands. Due to the decrease in their number, the excretory function of the skin is weakened (Khrisanfova, 1999).

► Significant changes are happening to the hair. Starting from the age of 30, the density of hair on the skin decreases (the density is a number of hair on a surface unit), they turn gray, that is, they cease to be colored with pigment. One of the reasons for graying is that the cells of the hair follicles (melanocytes) lose the ability to form a dye pigment. However, it is expected that another, more important reason is violation of a process of pigment transfer from melanocytes to the growing hair (Prokhorov, 2015b). Although hair growth is declining, older women often have facial hair (on the upper lip and chin). At the same time, hair on the body, limbs and eyebrows may disappear after 60 years.

► The bone system worsens, the curvature of the spine increases; intervertebral discs and cartilage of the articular surfaces of the bones flatten. A permanent sign of aging over the age of 45—50 years is bone thinning – osteoporosis.

► With age, there occur changes the overall size, shape and body composition, soft parts of the face.

► The height of a person decreases. According to some data, after 60 years, the height of men and women decreases by an average of 0.5—1.0 cm over a five-year period. This is due to the flattening of the intervertebral discs and increased stoop.

►There occur changes in the ratio of body components – muscle and fat. The amount of muscle tissue attains a peak at the age of 20—30 years, then its decline begins, at first slowly, and then with increasing rate, especially after 50 years. In this connection there occurs a decrease in muscle strength; at the age of about 70—80 years such strength reduced approximately two times. The subcutaneous fat layer decreases and the volume of internal fat in the abdominal area increases.

►Aging of the nervous system manifests itself in many ways. This applies to both the Central nervous system (brain) and the peripheral nervous system. Aging is manifested in functional and psychological changes that affect mental and physical performance, memory, emotions, complex behavioral reactions and other aspects of life. Structurally, aging is expressed primarily in reduced number of nerve cells – neurons. Although some reduction may occur already shortly after birth, a significant loss takes place in relatively late period, since the age 50—60 years, and such reduction is uneven in different areas of the brain. The degree of neuronal loss in the brain cortex of old people can reach as much as 40—50% or even more. In old age, neuronal density and size of neurons, diminish, together with deposition of pigment.

Age phenomen are also observed in the spinal cord and peripheral nervous system, they are observed in all parts of the vegetative nervous system (Khrisanfova, 1999).

– Aging worsens the condition and functions of other systems, tissues and organs of the body, including sense organs, cardiovascular, autonomic and immune systems, digestive organs, endocrine system, etc. (Guide to gerontology, 2005).

Now we can definitely affirm that senile changes may not be completely eliminated with diet, use of herbs, drugs, vitamins, physical exercise and the like.

How can we stop aging? The following sections will be described that the first step has already been done, and it is a cell therapy for a skin by its own cells. The next steps will be aimed at improving this technique and extending it to other tissues, systems and human organs.