Causes Wrinkles
Skin consists of three layers - epidermis, dermis and hypodermis, the latter also known as subcutaneous fat.
Epidermis
The epidermis is the outer layer of skin barrier function and aggression as factors in the environment. Epidermal cells - called keratinocytes - forwards in the basal skin layer, as the advances, this cell wall thickens and inside them is occupied by a protein called keratin. Once he arrived in the stratum corneum, Keratinocytes become detached from the skin surface, a process called desquamation. Anomalies appeared in the peeling process can cause the appearance of aggregates of keratinocytes called scaling.
Dermis
The second layer of skin is the dermis, composed of connective tissue. There are several types of connective tissue in the
body, each having a specific function. Skin, collagen offers resistance, retain glicozaminoglicans water leather and fiber elastic underlying elastic properties of skin.
Derma-epidermal junction
Derma-epidermal junction is a structure of utmost importance, is composed of digitiforme extension of the two structures, called the dermal papillae and papillary increases. Epidermis cells are fed by the blood vessels in the dermis, a process mediated by dermal-epidermal junction. The latter also has the role to increase the surface exposure of epidermis to blood vessels in the dermis, to ensure a Nutrition adequate layer of skin.
Subcutaneous fat.
Hypodermis contains adipose tissue consisting of cells called adiposities. They are designed insulator body and also keep the skin stretched, preventing the appearance Wrinkle.
Aging and wrinkles
As a person ages, epidermal cells become thinner and less adherent, which significantly reduces the skin thickness. Decreased intercellular adhesion leads to increased water loss from the skin barrier, resulting in skin tend to dry. Manufacturer epidemic cells decreases by 10% with each passing decade, and their breeding rate is increasingly lower, leading to lower repair capacity of skin.
Aging effects are considerable and the dermis: not only it is thinner, but the amount of collagen produced is reduced and elastic fibers breaks down. These structural changes lead to intimate skin wrinkles. Also in the dermis, sebaceous glands to increase production but increasingly less sebum, and the number sweat glands decreases, leading to increased tendency to dry skin.
Derma-epidermal junction are flattening, making the skin becomes thinner and less resistant. Moreover, and concentration of nutrients available to feed the epidermis decreases by reducing surface contact between epidermis and dermis, the process of repairing skin is also altered. Adiposities shrinks along with age, this change contributes to the appearance wrinkle, as it decreases the amount of fat that serves as a support for coating the skin.
History exposure to ultraviolet wrinkles
Exposure ultraviolet radiation sunlight spectrum is responsible for 90% of premature aging events skin. UV effects become apparent since the third decade of life and depend on the total dose of ultraviolet radiation received by the skin over the years with effect summation, and the type of skin pigmentation proper to each person.
Sun exposure effects on the epidermis
Sun causes thinning of epidermis and skin lesions called actinic keratosis, Basal cell carcinoma or squamous cell carcinoma.
Sun exposure effects on dermal
The dermis, sun cause fiber breakage collagen and accumulation of abnormal elastic fibers. These changes appear in aging skin but to a lesser extent than in skin chronically exposed to sunlight. With the modified elastic accumulation occurs in high amounts and some enzymes called metalloproteinase, enzymes that normally remodel the skin exposed to sunlight through remodeling of collagen fibers.
In some cases not fully known, these enzymes produce and destruction of collagen fibers which cause disruption of fibrils with the appearance of solar keratoses. When abnormal remodeling process is repeated many times, skin wrinkles make their appearance.
External factors on wrinkles
Wrinkles and Free Radicals
Free radicals are reactive oxygen species that have only one electron instead of two. As the tendency is to form pairs of electrons, free radicals take over electrons from other molecules, which in turn are forced to take electrons from other molecules and other continuous process lead to changes in cell function and alter genetic material. Free radicals which in turn activate metalloproteinase destroy collagen fibers, which results in the appearance wrinkle. Appearance of free radicals and trigger links of these processes are caused by exposure to ultraviolet radiation, smoking and air pollution.
Hormone effects on wrinkles
Although currently not established that the skin changes are due solely hormonal factors, it seems that lower level estrogen once Menopause can lead to skin changes. In experimental animal models could be seen that with decreasing levels of estrogen, the skin is thinner by 1% per year and the amount of collagen decreases by 2% each year.
Using facial muscles and wrinkles
Movements mimic muscles underlying wrinkles and decrease skin elasticity. Frown lines on the forehead and look for "goose foot" on the external angle of the eye arising from the repeated contraction of facial expression muscle aging, mainly acting muscles in these areas.
Gravity and wrinkles
Gravity makes lax skin to become increasingly apparent, leading eventually to the appearance aspect of "stationary" and the appearance of "drooping eyelids ". | 
