Pomegranate extract may stop inflammation, says Bugs

The activity of cyclooxygenase enzymes associated with inflammation, COX-1 and COX-2, was inhibited in animals fed a polyphenol-rich extract of pomegranate fruit, according to results published in the open-access Journal of Inflammation .

If the study can be repeated in humans it offers promise for preventing chronic inflammation, brought about by an over-expression or lack of control of the normal protective mechanism.

Chronic inflammation has been linked to range of conditions linked to heart disease, osteoporosis, cognitive decline and Alzheimer's, type-2 diabetes, and arthritis.

It is in terms of arthritis that the researchers focus their study, and indicate that pomegranate extracts could provide an alternative to use of non-steroidal anti-inflammatory drugs (NSAIDs), especially in light of mounting concerns about the adverse effects of NSAID use.

Some of these drugs, which are among the most frequently prescribed medications worldwide, have been linked with gastrointestinal toxicity, increased blood pressure, and increased risk of cardiovascular disease.

"Consumption of pomegranate fruit extract may be of value in inhibiting inflammatory stimuli-induced cartilage breakdown and production of inflammatory mediators in arthritis," wrote the researchers, led by Tariq Haqqi from Case Western Reserve University in Cleveland, Ohio.

Pomegranate, a rich source of antioxidants, has been linked to improved heart health, but a growing body of science indicates the fruit protect against prostate cancer.

Studies have also reported a role in joint health by slowing cartilage loss in arthritis.

It is these antioxidants, and particularly ellagitannin compounds like punicalagins and punicalins, which accounts for about half of the fruit's antioxidant ability, that are reportedly behind the proposed health benefits.

Study details Haqqi and co-workers fed four rabbits the pomegranate extract, equivalent of 175 ml of pomegranate juice, while two rabbits given water instead acted as the controls.

Blood samples were taken to measure inflammatory biomarkers and antioxidant levels.

The data showed that blood antioxidant levels were significantly higher after ingestion of the pomegranate extract, indicating the bioavailability of the antioxidants.

Moreover, COX-1 and COX-2 activity was significantly reduced in the pomegranate-fed animals, compared to control, particularly for COX-2.

Indeed, COX-1 activity was reduced by about seven per cent following ingestion of the extract, while COX-2 activity decreased by about 26 per cent.

"Although direct inhibitory effect of plant extracts or components on COX enzyme activity have been reported by several investigators, inhibition of COX enzyme activity by polyphenols that become bioavailable after consumption of pomegranate fruit or extract has not been reported," wrote the researchers.

While the results are promising for pomegranates, the researchers rightfully stated that additional animal studies are required, "followed by controlled clinical trials."

Source: Journal of Inflammation Open access journal, available here "Bioavailable Metabolites of Pomegranate (Punica granatum L) Fruit Extract Preferentially Inhibit

COX2 Activity ex vivo and IL-1b-induced PGE2 Production in Articular Cartilage Chondrocytes in vitro" Authors: M. Shukla, K. Gupta, Z. Rasheed, K.A. Khan, T.M. Haqqi