Red Raspberry Extract May Help Arthritis
A new study suggests red raspberries are not just another great tasting fruit. Researchers at the University of Rhode Island report that red raspberry extract reduced inflammation, cartilage damage, and bone resorption and thus may prove helpful in modulating the development and severity of arthritis.
Red raspberries are rich in antioxidants
Berries as a whole are power houses of plant substances called polyphenols that include the potent antioxidants anthocyanins and ellagitannins, which also boast anti-inflammatory properties. In fact, a University of California, Los Angeles, article published in the Journal of Agricultural and Food Chemistry noted that “An overwhelming body or research has now firmly established that the dietary intake of berry fruits has a positive and profound impact on human health, performance, and disease.”
The red raspberry (Rubus idaeus) is among those berry fruits, and it was the subject of a recent study in which investigators used a red raspberry extract to explore its abilities to protect cartilage and provide anti-inflammatory benefits in an arthritis rat model.
The red raspberry extract used in the study contained 20% total polyphenols, 5% anthocyanins, and 9.25% ellagitannins. Three groups of rats with induced arthritis were used: one group was given 120 mg/kg red raspberry extract, another was given 30 mg/kg, and the controls received none.
Compared with controls, the rats given the higher dose of red raspberry extract had a lower incidence and severity of arthritis. The researchers also conducted a cell study, and they found that the extract decreased the rate of degradation of two key components of joint cartilage—type II collagen and proteoglycan.
When the authors conducted a histological analysis, they found that the red raspberry extract had significantly inhibited inflammation, cartilage damage, and the formation of pannus (tissue that can form in the joints and lead to cartilage destruction and bone erosion), as well as the resorption of bone.
Red raspberry has been studied for other medicinal purposes. In a recent study from Clemson University, researchers examined the effect of red raspberries on killing cancer cells. They found that the antioxidants had a more significant role in killing breast cancer cells than gastrointestinal cell types.
The University of Rhode Island study results suggest red raspberry extract may help protect the cartilage and have a positive impact on the onset and severity of arthritis. Since polyphenols are extensively metabolized, the metabolites could contribute to the health benefits of red raspberries, a concept that further studies need to investigate.
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