240 - Decreased Intracellular Glutathione in Peripheral Neutrophils Decreases Chemotactic Behaviour towards Interleukin 8 and FMLP

Abstract

The innate immune system is the first line of defence against invading microorganisms, and neutrophils are the most abundant leukocyte and the first to arrive at a site of infection. Periodontitis is a highly prevalent chronic non communicable disease and in its most severe form is the sixth most prevalent human disease, affecting 11.2% of the world’s population. It has been associated various systemic diseases and conditions, such as diabetes. In periodontitis it is known that neutrophils have aberrant chemotactic behaviour (Roberts et al PMID: 25360483), as well as increased reactive oxygen species production whilst resting (hyper activity) and when stimulated (hyper-reactivity) (Matthews et al PMID: 17223966). This combination may lead to enhanced tissue damage in the periodontal lesion. We have also shown that levels of glutathione in the periodontal lesion (Grant et al PMID: 19968740) and within circulating peripheral neutrophils (Dias et al PMID: 23826097) are decreased, demonstrating a loss in redox buffering and capacity. Previous studies have shown the importance of glutathionylation of actin in chemotactic movement of neutrophils (Sakai et al 2012 PMID: 23159440). With the long term aim to examine how diminished glutathione levels in periodontitis effect chemotaxis, we examined the effect of glutathione modulation by buthioninesulfoximine (BSO), N-acetylcysteine (NAC), bis-chloroethylnitrosourea (BCNU) and 1-chloro-2,4-dinitrobenzene (CDNB) on neutrophil intracellular glutathione, viability and chemotaxis towards interleukin 8 and N-formylmethionyl-leucyl-phenylalanine (fMLP). BSO, BCNU and CDNB decreased the chemotaxis and glutathione levels in peripheral neutrophils isolated from healthy donors. Future studies will translate this work into a periodontal cohort and examine protein glutathionylation by mass spectrometry.