Background & aim: Recently, the interaction of lipopolysaccharide activated by mesenchymal stem cells and neutrophils has been proven. The aim of the present study was to evaluate the effect(s) of the Green tea extract, as a widely consumed beverage on the interaction of lipopolysaccharide activated MSCs on neutrophils.

Methods: In the present experimental study, after the isolation of mesenchymal stem cells from bone marrow of rats was conducted, these cells were stimulated with 10 ng/mL LPS for 1. Then, the supernatant was discarded and washed out to remove LPS cells.  Afterwards, the cells were incubated with different concentrations of green tea (10, 100 and 500 micrograms per ml) for 24 hours. Subsequently, the mesenchymal stem cells were co-cultured with neutrophils and incubated for other 4 h. Finally, the neutrophil function was evaluated. The data were analyzed by Kruskal wallis test. P values less than 0.05 were considered statistically significant.

Results: Pro-inflammatory mesenchymal stem cells (Challenged with LPS) caused a decrease in vitality, Neutral Red-uptake and respiratory burst of activated neutrophils. Treatment of pro-inflammatory mesenchymal stem cells with higher concentration of green tea extract potentiated the decrease rate of Neutral Red-uptake and respiratory burst of activated neutrophils. Moreover, the vitality of neutrophils increased in a dose-independent manner by green tea extract. 

Conclusion:It seemed that the treatment of mesenchymal stem cells in inflammatory condition with Green tea extract may potentiate the role of mesenchymal stem cells to increase phagocytosis and the respiratory burst of neutrophils cells.