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Atrophy

life science Maturity 11-13 Next article →

Atrophy is when a part of the body wastes away. This can happen to a tiny cell or a large organ. It usually happens after the part has already finished growing to its full size. This is different from hypoplasia. Hypoplasia is when an organ does not reach its normal maturity.

Atrophy can be a normal part of how our bodies work. It can also be a sign of a problem. When it happens because of a disease, doctors call it pathological atrophy. It is a way the body breaks down and reabsorbs its own tissues.

Many things can cause this wasting to happen. A part might waste away if it does not get enough food or blood. It can also happen if a part loses its nerve supply. Sometimes, the body cells undergo apoptosis. This is a process where cells break themselves down.

Hormones also help keep organs healthy. Doctors say these hormones have trophic effects. If these signals stop, the organ may shrink. This can happen if there is a mutation in a gene. A mutation can destroy the instructions needed to build an organ.

Atrophy can be a normal part of growing up. For example, the thymus shrinks during early childhood. The tonsils also shrink during adolescence.

As people get older, atrophy happens in different ways. Skin may become thin and create wrinkles. People might lose their hair or their teeth. Muscles can also become weaker in old age. This is sometimes called sarcopenia. Scientists are still studying the exact causes of sarcopenia. It may involve satellite cells that help fix muscle fibers.

Muscles can waste away if they are not used. This is called disuse atrophy. It can happen if a person stays in bed for a long time. It also happens if a limb is kept in a cast. Most of the time, you can fix this with exercise.

Some diseases cause much more severe wasting. Cancer and AIDS can cause a syndrome called cachexia. This causes very severe muscle loss. Other conditions like liver disease can also cause this. Nerve diseases like ALS or polio can also cause muscles to wither.

Different parts of the body react to atrophy in unique ways. The adrenal glands can shrink if someone uses certain medicines. In women, the walls of the vagina may become thinner after menopause. This happens because estrogen levels go down.

Scientists even tested a drug on mice to stop muscle loss. The drug blocked a specific protein in the muscle. However, the drug had bad effects on the heart. Because of this, researchers are still looking for better ways to help.

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