ABSTRACT
Berries are an important dietary source of fibres, vitamins, minerals and some biologically active non-nutrients. A red raspberry fruit extract was characterized in terms of phenolic content and the anti-inflammatory properties and protective effects were evaluated in two experimental models of inflammation. The antioxidant potential of the extract, the cellular antioxidant activity and the effects over neutrophils' oxidative burst were also studied to provide a mechanistic insight for the anti-inflammatory effects observed. The extract was administered in a dose of 15 mg kg(-1), i.p. and significantly inhibited paw oedema formation in the rat. The same dose was administered via i.p. and p.o. routes in the collagen-induced arthritis model in the rat. The extract showed pharmacological activity and was able to significantly reduce the development of clinical signs of arthritis and markedly reduce the degree of bone resorption, soft tissue swelling and osteophyte formation, preventing articular destruction in treated animals.
Subject(s)
Anti-Inflammatory Agents/administration & dosage , Anti-Inflammatory Agents/chemistry , Arthritis/drug therapy , Edema/drug therapy , Plant Extracts/administration & dosage , Plant Extracts/chemistry , Rosaceae/chemistry , Animals , Antioxidants/administration & dosage , Antioxidants/chemistry , Arthritis/immunology , Disease Models, Animal , Drug Evaluation, Preclinical , Edema/immunology , Fruit/chemistry , Humans , Male , Neutrophils/drug effects , Neutrophils/metabolism , Oxidative Stress/drug effects , Rats , Rats, WistarABSTRACT
In this work, Opuntia ficus indica juice was explored as a potential source of natural antioxidant and anti-inflammatory ingredients towards intestinal inflammation. An adsorption separation process was used to produce a natural flavonoid-rich concentrate (FRC) from Opuntia ficus-indica juice. The FRC effect (co- or pre-incubation) on induced-oxidative stress and induced-inflammation was evaluated in human Caco-2 cells. The main constituents identified and present in the extract are flavonoids (namely isorhamnetins and their derivatives such as isorhamnetin 3-O-rhamnose-rutinoside and isorhamnetin 3-O-rutinoside) and phenolic acids (such as ferulic, piscidic and eucomic acids). Our results showed that co-incubation of FRC with the stress-inducer attenuates radicals production in a much more significant manner than pre-incubation. These results suggest that FRC compounds which cannot pass the cell membrane freely (isorhamnetin derivatives) have an ability to inhibit the formation of H2O2-induced radicals in the surrounding environment of intestinal epithelial cells. The capacity of FRC (co-incubation) for suppressing (at the extracellular level) free radicals chain initiation or propagation reaction was probably related with a more pronounced reduction in protein oxidation. A similar response was observed in the inflammatory state, where a marked decrease in IL-8 secretion and blocked degradation of IκBα was achieved for FRC co-incubation. Simultaneously, treatment with FRC significantly reduces NO and TNF-α expression and modulates apparent permeability in Caco-2 cells. In these cases, no significant differences were found between pre- and co-incubation treatments suggesting that bioavailable phenolics, such as ferulic, eucomic and piscidic acids and isorhamnetin, act at the intracellular environment.
