From VOA Learning English, this is the Health and Lifestyle report.

　　Researchers say a number of drugs currently used to treat autoimmune diseases also appear to treat signs of depression.

　　These medicines are known as anti-inflammatories. They help to reduce inflammation in the body. Inflammation is the pain and expansion, or swelling, of damaged tissue.

　　What is an autoimmune disease?

　　An autoimmune disease is a disease where the body attacks itself. Examples include the skin condition psoriasis, rheumatoid arthritis, type 1 diabetes and Crohn's disease.

　　White blood cells are part of the body's natural defense against disease. They help to protect us against infection. In autoimmune diseases, the white blood cells are over-activated. Instead of simply attacking bacteria and viruses, the body's natural defense system also attacks healthy tissue.

　　To treat an autoimmune disease, patients often are told to take anti-inflammatory drugs. Now, a study suggests that the drugs also appear to treat signs of depression. The study also suggests that anti-inflammatory medicines may soon take their place with traditional treatments to help people with this disorder.

　　Researchers looked at a number of drug studies that involved patients with autoimmune diseases. They noted an improvement in patients with signs of depression after the research ended.

　　Anti-inflammatory drugs quiet the body's natural defenses by disarming proteins known as cytokines. These proteins are important in the body's reaction to inflammation. A small amount of inflammation is necessary to activate the immune system to fight an infection. But too much pain or swelling is harmful.

　　Golam Khandaker is a professor of psychiatry at the University of Cambridge.

　　"Slow burning inflammation that's circulating in our body can cause a number of physical and psychiatric conditions. For example, in the brain, it could lead to increased risks of depression. Similarly in the body, it could lead to increased risk of heart disease, particularly coronary heart disease such as stroke ... or also type 1 diabetes or type 2 diabetes."

　　People with autoimmune diseases often suffer from depression. Some earlier studies suggested these people are depressed because of their condition. But the new study suggests that inflammation changes the chemistry of the brain, causing depression.

　　Antidepressant drugs work to help to re-establish the operation of brain chemicals, called neurotransmitters. However, the drugs are not always successful in treating patients with depression.

　　Anti-inflammatory drugs, which work differently in the brain, give doctors another choice.

　　For the study, Khandaker and his team looked at the results of 20 studies of people treated with anti-inflammatory drugs. These patients had arthritis, psoriasis or Crohn's disease.

　　The researchers found that individuals who reported signs of hard-to-treat depression before the study had a mild to moderate reduction in those symptoms after the study. In fact, the results were similar to the effectiveness of antidepressants.

　　"And what they showed is that patients who were inflamed at the beginning of the trial showed benefits from the anti-cytokine drug. And the higher the level of inflammation, the greater the improvement in the severity of depressive symptoms."

　　The researchers published their findings in the journal Molecular Psychiatry.

　　Researchers say anti-inflammatory drugs could someday be used in patients with depression for whom other drugs have failed.

　　Depression will be the second highest cause of disease burden in middle-income countries by the year 2030. This prediction comes from the World Health Organization.

　　For the Health & Lifestyle report, I'm Anna Matteo.

　　VOA science reporter Jessica Berman wrote this story for VOANews. Anna Matteo adapted it for Learning English. George Grow was the editor.