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(photo credit: Courtesy)
Injections of tiny globules of fat using nanotechnology have been proposed by researchers at the Technion-Israel Institute of Technology and the Hebrew University of Jerusalem to treat the degenerative disease osteoarthritis, the erosion of cartilage in the joints.
The innovative technology will be presented next week at a joint workshop of Israeli and Chinese scientists at the Technion's campus in Haifa.
There are about 27 million osteoarthritis patients in the US alone, and it is estimated that 80% of the population will have radiographic evidence of the disease by the age of 65.
The researchers aim to help osteoarthritis patients avoid surgery to replace damaged hip joints and minimize pain by injecting the liposomes into the joints. The liposomes were developed by Hebrew University biochemistry Prof. Yechezkel Barenholz, a world-renowned expert in lipsome fat globules who co-developed Doxil, the world's first approved nanotechnology medicine for slow-release of chemotherapy for breast and ovarian cancer that is in the process of being authorized for other cancers as well.
Nanotechnology deals with structures on the molecular or atomic scale of 100 nanometers - one billionth of a meter - or smaller.
In the experimental treatment, globules of phospholipids would be injected into the joint.
"Cartilage is only two millimeters thick," says Prof. Yitzhak Etzion from the Technion's mechanical engineering faculty. "It is sponge-like material that separates the bones of the joint and allows them to move with minimal friction between them."
The joint space contains synovial fluid aimed at lubricating the joint. But when this fluid is inflammatory and not healthy, the cartilage becomes eroded, and the bones are in direct contact. This results in severe pain and limitation of physical movement.
Major surgery is conventionally used to replace the sick joint. But now Barenholz and Etzion have joined together to delay or prevent the operation by reducing damage to the cartilage. Currently, doctors inject the joint with hyaluronic acid, which is meant to improve lubrication - but there is no medical evidence that it in fact ameliorates the problem.
As Barenholz has long been developing liposomes, these fatty microparticles will be used to minimize friction. Etzion tested the liposomes in his lab with large and small pieces of bone and cartilage facing each other. They are paired in a physiological liquid in which nanolipids float. The pieces are circulated under pressure as a model of how hip joints move. Thus they were able to test the efficacy of the fatty globules in minimizing friction and erosion of the cartilage and bones.
Tests showed that the pace of erosion decreased by 40 percent when liposomes were added to hyaluronic acid compared to hyaluronic acid alone. The two scientists registered a patent on their technology and established a company based on it. Their findings were published recently in the scientific journal Wear.