Enhancement of vitamin C on PMN function in healthy individuals

Abstract

Abstract Vitamin C (ascorbic acid, ascorbate) promotes immune cell activities by supporting various cellular functions especially, in neutrophils or polymorphonuclear (PMN) leukocytes, which play an important role in bacterial infection and acute inflammation. Little data have been reported in impact of vitamin C on PMN function during bacterial phagocytosis in healthy individuals. Here, we have elucidated the effect of vitamin C on PMN phagocytosis and oxidative burst to Staphylococcus aureus by whole blood assay and flow cytometry after pre-incubation without and with vitamin C in vary concentrations. The results showed that vitamin C concentration at 20 mM induced a significant increase phagocytosis (p-value=0.03) and had trend to significant increase oxidative burst (p-value=0.06) while vitamin C concentration of 30 mM showed significant increase both phagocytosis and oxidative burst (p-value=0.04 and 0.02, respectively) at only 15 min of exposure to the bacteria. As a minimal concentration that can increase phagocytosis, we selected vitamin C at 20 mM as optimal concentration to investigate more data by enrollment of healthy volunteers (n=17). The results revealed significant difference both phagocytosis and oxidative burst after 20 mM vitamin C pre-incubation (p<0.0001). In conclusion, we showed that vitamin C at 20 mM can boost phagocytosis and oxidative burst of neutrophils in healthy adults within 15 min after bacterial exposure. This rapid activation may be applied to fight bacterial infection. Nevertheless, further research in clinical trial and underlying mechanisms await further studies.