The findings, although still at a preliminary stage not yet proven in humans, are likely to encourage further consumption of pomegranate juice in the UK, where sales have rocketed in the last year thanks to media coverage of its antioxidant content.
A team from the Case Western Reserve University found that a water extract of pomegranate fruit inhibited stimulation of certain enzymes in human cartilage cells affected by osteoarthritis.
Production of these enzymes, matrix metalloproteases, is speeded up by the pro-inflammatory protein interleukin-1b (IL-1b) during osteoarthritis, leading to cartilage degradation and damage to joints.
Writing in this month's issue of the Journal of Nutrition, Tariq M. Haqqi and colleagues said the findings suggest that consumption of pomegranate fruit extract "may help in protecting cartilage from the effects of IL-1b by suppressing cartilage degradation in osteoarthritis".
Further research will be needed to determine the absorption rate of pomegranate fruit extracts in the joints and to confirm in animals whether the fruit extract promotes cartilage repair.
However the findings offer significant hope for the huge and growing numbers of people affected by arthritis.
More than 7 million adults in the UK - 15 per cent of the population - have long-term health problems due to arthritis and related conditions, according to the Arthritis Research Campaign, and 550,000 have moderate to severe osteoarthritis in their knees.
Yet despite the expected increase in incidence of arthritis in coming years, impacted by the rise in obesity, there are few treatments available and they do little to slow joint destruction and disease progression.
"This has generated considerable interest in the identification and development of new approaches and reagents to treat and inhibit, if not abolish, the progress of the disease," said Dr Haqqi.
He added that arthritis is one of the foremost diseases for which patients seek herbal or traditional medicine treatments.
If future studies prove positive, pomegranate fruit extract could be successfully used in supplements or foods as it is already safely consumed in the form of juice.
In addition, the fruit's antioxidants are rapidly absorbed by the body.
Animal studies have previously suggested that pomegranate fruit extract consumption may also be anticarcinogenic, while human trials have indicated benefits for the heart.
These benefits are thought to be at least partly responsible for the 300 per cent increase in sales of the juice in the UK since the start of the year to 500,000 litres per month currently.