Pomegranate extract may benefit eye health, study finds
The study observes that in the cellular condition where PMX was cultured with the lipopolysaccharide (LPS), there was a significant reduction in the levels of pro-inflammatory cytokine IL-8, when compared with the condition containing LPS alone as well as the control.
Furthermore, the percentage of IL-8 release inhibition was greater in the PMX condition when compared to the further conditions, suggesting the compound’s ability to mediate the inflammatory response within the corneal epithelial cells.
Andrea Zangara, Head of Scientific Communication & Medical Affairs at Euromed S. A and co-author of the study, states: “Despite pomengranate’s various benefits for overall wellbeing, there is limited data on how it can support eye health. So far, experimental studies have mostly examined the antioxidant activity and not the anti-inflammatory potential of Pomanoxin corneal tissue samples.
“This latest study provides evidence of its possible use for eye health, which is promising. Considering the ageing population and increasing screen time embedded into our daily lives, vision health looks set to become one of the key concerns for consumers globally,” he stresses.
Nutrition for eyesight
The corneal epithelium is an essential layer within the eye providing protection against the external environment; which when damaged can stimulate proinflammatory pathways, resulting in possible scarring, loss of transparency, and decreased visual acuity. Additionally, the epithelium is involved in the ocular immune response which leads to the production of further proinflammatory cytokines, including IL-1β.
It has been reported that overproduction of such cytokines can cause corneal ulcer formation. Therefore, it has been proposed that targeting this pathway stimulation utilising natural anti-inflammatory products may be effective for its prevention.
Certain fruits, such as pomegranates, have demonstrated strong antioxidant and anti-inflammatory potentials due to their high concentrations of active phytochemicals. Note-worthy types found to be responsible for the associated health benefits include the hydrolysable tannins and polyphenols.
Previous human trials utilising the Pomanox pomegranate juice and extracts have noted its potential ability to reduce risk of inflammation, cardiovascular disease, and diabetes. Yet, there is limited data available on the effects of pomegranate on eye health. Thus, the researchers sought to investigate the anti-inflammatory potential of Pomanox within the human corneal epithelium, through cytokine secretion modulation.
The researchers conducted the in vitro study testing the cell viability and inhibition of interleukin-8 (IL-8) within four separate conditions: negative control, positive inflammatory control with lipopolysaccharide (LPS) from Escherichia coli, positive anti-inflammatory control (LPS with dexamethasone), and LPS with PMX extract after 24 hours of culturing.
The results showed that there were significantly lower levels of IL-8 observed in the PMX condition with 48.7 pg/ml, compared to 172.7 pg/ml in the LPS with E. coli condition.
It was established that the percentage of inhibition of IL-8 release were significantly greatly for the LPS with PMX condition (63.8%), compared to LPS with dexamethasone (45.7%).
In addition, the percentage of cell viability was found to be greater in the LPS with PMX condition with 86%.
The new study findings suggest that the pomegranate extract may have a strong anti-inflammatory potential via inhibiting the release of IL-8 following inflammation triggered by LPS.
With regards to the suggested mechanism of action, the researchers explain a specific polyphenol compound may be responsible, explaining: “Punicalagin regulates signalling pathways in inflammation-associated disorders, and numerous experimental studies in inflammatory models have shown that treatment with punicalagin significantly reduced inflammatory markers and TNFα-induced expressions of pro-inflammatory cytokines, including IL-8.”
The researchers stress the need for further study utilising human trials with higher levels of control to further validate the findings and potentially influence the eye health category.
“In Vitro Anti-Inflammatory Potential of Pomegranate Extract (Pomanox®) in a Reconstituted Human Corneal Epithelium Model”
by Marcos Peñalver-Mellado, Fredy Silva-Fuentes, Agustín Villar, Anna Mula and Andrea Zangara