Health & Medicine / Pharmaceuticals

Faced with the pain of rheumatoid arthritis, many Chinese seek relief in a weed called thunder god vine, which grows wild in southern China. Now Stanford researchers have shown that this is one folk remedy that looks just as impressive in the lab. They proved how a versatile chemical in the herb could work to alleviate a variety of autoimmune diseases and even fight cancer.

The Chinese plant helps by jamming a crucial bit of the cellular machinery, says Peter Kao of Stanford. When the body reacts to infection, a protein known as NF-kB switches on a set of genes that triggers inflammation. Transplanted organs provoke the same reaction, unfortunately. Sometimes the body even turns on itself, causing autoimmune disorders. Kao discovered that triptolide, a chemical in the vine, prevents inflammation, apparently by slipping into the immune cells and blocking NF-kB. In a separate Stanford study, triptolide also caused cancerous cells to commit suicide. "This is a powerful pharmacologic tool," says Kao.

He finds that triptolide is more potent than the drugs used to prevent the rejection of organ transplants, and it may produce fewer side effects. He also considers it a promising treatment for rheumatoid arthritis and many other autoimmune problems.