Protective effects of a blueberry extract in acute inflammation and arthritis in the rat

What is it about?

This work investigated the anti-inflammatory effects of a blueberry extract in a carrageenan-induced paw edema model and collagen-induced arthritis model, both in rats. Along with the chemical characterization of the phenolic content of the fruits and extract, the antioxidant potential of the extract, the cellular antioxidant activity and the effects over neutrophils' oxidative burst, were studied in order to provide a mechanistic insight for the anti-inflammatory effects observed. The extract significantly inhibited paw edema formation in an acute model the rat. Results also demonstrate that the standardized extract had pharmacological activity when administered orally in the collagen-induced arthritis model in the rat and was able to significantly reduce the development of clinical signs of arthritis and the degree of bone resorption, soft tissue swelling and osteophyte formation, consequently improving articular function in treated animals.

Featured Image

Photo by Stephan H. on Unsplash

Photo by Stephan H. on Unsplash

Why is it important?

The chemical characterization of the blueberry extract with HPLC-DAD and LC-ESI–MS/MS allowed the research team to conclude that the blueberries used have a wide range of phenolic compounds. The most common flavonol was identified as being quercetin. A significant portion of the extract is constituted by anthocyanins. The team also demonstrated that this extract has high antioxidant capacity both in vitro and in vivo. In a CIA animal model the blueberry extract, when administered orally for 13 days was able to visibly reduce edema formation but also delayed the development of the clinical signs on days 24–35 and improved the histologic and radiographic scores of the knee joint and hind paw. Taken together, these results are good indicators for the use of the blueberry extract as a therapeutic adjuvant in the treatment of rheumatoid arthritis. This is particularly important in a poly-medicated population that will benefit from this adjunctive therapy or supplementation. The effects we observed in the current work can be translated to practice or to a pharmaceutical dosage, when formulated as a supplement, considering the average consumption of blueberries in the population. This work provides a mechanistic explanation for these observations and support the idea that a blueberry extract could be used as an adjunctive therapy. This is a clear translational example of how a functional food can improve quality of life when having pharmacological impact on a body function.

Perspectives