A new marker for osteoarthritis
Osteoarthritis (OA) is a common, crippling age-related disease characterized by the gradual destruction of cartilage cushioning the joints. To assess cartilage erosion, doctors routinely rely on measurement of the joint space width using radiographs. To be visible on an X-ray film, however, significant cartilage degradation must have already occurred. By the time radiographs reveal destruction, the damage to the joint is usually irreversible. Due to this method’s relatively insensitive nature, it also takes at least a year or two to detect progression of damage that has been captured on radiographs.
To improve the early diagnosis and effective treatment of OA, medical researchers have turned to the promise of biochemical markers – molecules released into bodily fluids during the process of tissue turnover. Recently, researchers in the Netherlands identified a novel marker linked to both the prevalence and the progression of OA, particularly at the knee and the hip. They share their breakthrough findings in the August 2004 issue of Arthritis & Rheumatism.
Building on the analysis of cartilage metabolism, the researchers concentrated on peptide fragments of type II collagen. Since type II collagen is located almost exclusively in cartilage, a fragment – abbreviated as CTX-II – was seen as a potential marker for cartilage destruction. To determine the relationship between CTX-II and OA, researchers drew on a large, established sample: 1,235 men and women ages 55 and older enrolled in the Rotterdam Study, a long-term research effort to investigate the incidence of, and risk factors for, chronic disabling diseases. Researchers followed up with participants, whose average was 66, over a time span of six-and-a-half years.
At the study’s onset, 19 percent of the subjects had clear radiographic evidence of OA in at least one knee; 10 percent had OA in at least one hip. At baseline, urine samples from all subjects were assessed for the concentration of CTX-II. The participants were then divided into four groups for further evaluation and continued monitoring, according to their levels of CTX-II.
According to the researchers’ calculations, subjects with a CTX-II level in the highest quartile had a 4-fold increased risk of developing OA in either the knee or hip compared with subjects in the lowest quartile. During the follow-up period, confirmed by repeated radiographs, subjects with the highest concentration of CTX-II were significantly more likely to experience rapid, destructive progression of OA – 6 times more likely at the knee and 8 times more likely at the hip. The subjects with the highest CTX-II levels also had the highest complaints of joint pain. In addition, the researchers found a slight rise in CTX-II concentration with increasing age among women. However, the strong correlation between CTX-II and both the incidence and severity of OA was shown to be independent of age, sex, and body mass index.
"This is the first large follow-up study in which the use of CTX-II as a biomarker for cartilage degradation and disease progression has been investigated," emphasizes the team’s leading researcher and spokesperson, M. Reijman, MSc. "Based on the results, we conclude that the CTX-II concentration is markedly associated with the prevalence and progression of OA of the knee and hip, and that these associations are independent of known risk factors for radiographic OA. The presence of joint pain seems to augment this relationship," he notes, "which might reflect the effects of an ongoing OA process. The increase of CTX-II in women after menopause may reflect a protective effect of estrogen against cartilage loss. Further research is necessary to establish the clinical utility of this novel biomarker for OA."
David Greenberg | EurekAlert!
The most recent press releases about innovation >>>
Die letzten 5 Focus-News des innovations-reports im Überblick:
On the way to an intelligent laboratory, physicists from Innsbruck and Vienna present an artificial agent that autonomously designs quantum experiments. In initial experiments, the system has independently (re)discovered experimental techniques that are nowadays standard in modern quantum optical laboratories. This shows how machines could play a more creative role in research in the future.
We carry smartphones in our pockets, the streets are dotted with semi-autonomous cars, but in the research laboratory experiments are still being designed by...
So-called pre-distorted states accelerate photochemical reactions too
What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...
For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.
Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...
At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.
No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...
Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.
Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...