Facts of lifeWrinkles …OH NO! [Archives:2005/867/Health]

By Dr. Khaled alNsour
For the Yemen Times
Getting older? Does it show on your face and hands? You are then defiantly thinking about wrinkles. You can often get an idea of how old someone is by looking at his or her face – specifically the skin. As people age, it's normal to get wrinkles. Wrinkles are visible creases in the skin and most wrinkles are associated with aging changes in skin. Aging of the skin and related structures (hair and nails) is a natural process. Nothing can be done to decrease the rate of skin aging, but many environmental factors will increase the rate. And if the person has spent a lot of time in the sun, at tanning salons, or smoking cigarettes, he or she might have a lot of them.

The skin is made up of three layers:

_ the outermost layer everyone can see, called the epidermis

_ the middle layer, called the dermis

_ the innermost layer, called the subcutaneous

When a person is young, he or she doesn't have wrinkles because the skin does a great job of stretching and holding in moisture. The dermis has an elastic quality thanks to fibers called elastin that keep the skin looking and feeling young. A protein in the dermis called collagen also plays a part in preventing wrinkles.

Dermal-Epidermal Junction

The junction between the dermis and the epidermis is an important structure. The dermal-epidermal junction interlocks forming finger like projections called rete ridges. The cells of the epidermis receive their nutrients from the blood vessels in the dermis. The rete ridges increase the surface area of the epidermis that is exposed to these blood vessels and the needed nutrients.

Subcutaneous Tissue

The bottom layer of skin is the subcutaneous tissue containing fat cells. These fat cells provide insulation to the body and make the skin look plump or full.

However, over time, the dermis loses both collagen and elastin, so skin gets thinner and has trouble getting enough moisture to the epidermis. The fat in the subcutaneous layer that gives skin a plump appearance also begins to disappear, the epidermis starts to sag, and wrinkles form.

There's not a magic age (like 40) when everyone suddenly gets wrinkles. Some people in their 20s have little wrinkles around their eyes (called “crow's feet”) from squinting or spending too much time in the sun.

Other people may be in their 50s or 60s before you can even see a wrinkle. This is usually because they have taken good care of their skin over the years and may have more sebum, the skin's natural oil. They may also have “good genes” – which means their family members don't have many wrinkles. Eventually, however, everyone will have at least a few wrinkles. It's a natural part of the aging process.

Aging Effects of the Sun and Wrinkles

Exposure to ultraviolet light, UVA or UVB, from sunlight accounts for 90% of the symptoms of premature skin aging. Most of the photoaging effects occur by age 20. The amount of damage to the skin caused by the sun is determined by the total lifetime amount of radiation exposure and the person's pigment protection.

Sunlight Effects on the Epidermis

Changes in the epidermis caused by the sun include thinning of the epidermis and the growth of skin lesions such as actinic keratoses, basal cell carcinomas, and squamous cell carcinomas.

Sunlight Effects on the Dermis

In the dermis, sun effects cause collagen to break down at a higher rate than with just chronologic aging.

Sunlight damages collagen fibers and causes the accumulation of abnormal elastin. When this sun-induced elastin accumulates, enzymes called metalloproteinases are produced in large quantities. Normally, metalloproteinases remodel sun-injured skin by manufacturing and reforming collagen. However, this process does not always work well and some of the metalloproteinases actually break down collagen. This results in the formation of disorganized collagen fibers known as solar scars. When the skin repeats this imperfect rebuilding process over and over wrinkles develop.

Free Radicals and Wrinkles

Free radicals are unstable oxygen molecules that have only one electron instead of two. Because electrons are found in pairs the molecule must scavenge other molecules for another electron. When the second molecule looses its electron to the first molecule, it must then find another electron repeating the process. This process can damage cell function and alter genetic material. Free radical damage causes wrinkles by activating the metalloproteinases that break down collagen. There are several factors that start this cascading process including exposure to even small amounts of UV radiation in sunlight, smoking, and exposure to air pollution.

Hormone Effects and Wrinkles

It is likely that there are skin changes as a result of the hormonal effects of menopause or decreased estrogen production. However, studies in humans have not documented which skin changes are specific to decreased estrogen and which skin changes are a result of sun exposure or just normal chronological aging. In animal experiments lack of estrogen can cause a decrease in collagen levels of 2% per year and a decrease in skin thickness of 1% per year.

Muscle Use and Wrinkles

Habitual facial expressions cause the skin to wrinkle as it looses elasticity. Frown lines between the eyebrows and crows feet radiating from the corners of the eyes develop as the tiny muscles in those areas permanently contract.

Gravity and Wrinkles

The effects of gravity make the loosening of the skin more apparent as skin sags more. This causes jowls and drooping eyelids.

Here are some things people can do to prevent getting many wrinkles at an early age:

_ Avoid spending too much time in the direct sun, especially during the hours when the sun's rays are harshest (between 10:00 AM and 4:00 PM). Ultraviolet (UV) rays cause many wrinkles. Sunblock helps, but it doesn't block out all the damaging UV rays that cause wrinkles to the skin. Still, if you are outside a lot, be sure to wear a sunblock with sun protection factor (SPF) 15 or higher and reapply often (every 2 to 3 hours). Always reapply after swimming or playing sports that make you sweaty!

_ Don't go to the tanning salon. The UV light from tanning booths is just as damaging as the sun's – and sometimes worse.

_ Don't smoke! Smoking robs your skin of precious moisture and causes premature (early) wrinkles. (Did you ever notice that most heavy smokers have wrinkles around their mouths?)

_ Drink water.

_ Moisturize dry skin, especially during months when the air is drier.
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