Discovery shows fat triggers rheumatoid arthritis

Scientists have discovered that fat cells in the knee secrete a protein linked to arthritis, a finding that paves the way for new gene therapies that could offer relief and mobility to millions worldwide.

"We found that fat in the knee joints secretes a protein called pro-factor D which gives rise to another protein known as factor D that is linked to arthritis," said Nirmal Banda, Ph.D., associate professor of medicine in the Division of Rheumatology at the University of Colorado School of Medicine. "Without factor D, mice cannot get rheumatoid arthritis."

Rheumatoid arthritis is an autoimmune condition that gradually destroy bones, muscles, joints, cartilage and other connective tissue. Over 1% or about 1.3 million Americans suffer from it.

Banda, senior author of the study published this week in the Journal of Immunology, has spent the last 14 years tracking down the causes of rheumatoid arthritis in collaboration with CU School of Medicine professors Michael Holers, MD, and William Arend, MD.

"We are looking at vaccines, drugs or inhibitors to stop the local secretion of pro-factor D in the mouse," he said. "Our goal would be to stop the disease before it progresses and leads to joint destruction."

Factor D is part of the complement system, a complex array of over 40 proteins that help the body fight off bacteria and other pathogens. In studies with arthritic mice, Banda previously found that the complement pathway involving factor D made the mice susceptible to inflammatory arthritis.

In his latest study, he discovered that removing factor D, rather than the entire complement system, achieves the same result without compromising other parts of the system that can fight infection.

Rheumatoid arthritis is an autoimmune disease in which your body starts destroying itself. It can be a devastating disease that can certainly destroy your health.

Of course, the U.S. "health" care system has evolved to one that focuses on using drugs and surgery as its primary treatment tool. This works exceptionally well for some diseases -- like acute trauma -- but for other diseases, especially autoimmune diseases like rheumatoid arthritis, it is an abysmal failure.

I have personally treated over 3,000 patients with rheumatoid arthritis in my practice, which is well more than 10 times the amount a typical family physician would treat in their entire career. So I have a fair amount of experience here.

"We know that fat is normally present around all organs of the body," he said. "But what we didn't know until now was that the fat is secreting this protein which actually triggers arthritis in the joints."

He noted that fat does the same thing in all the joints, not just the knees. That means new medications resulting from this discovery could treat inflammatory arthritis throughout the body.