evaluation of association between the serum levels of mmp9 and mmp9/timps with soluble forms of selectins and itching induced by sulfur mustard

Background & objective: pruritus is the most frequent chronic dermal complication of sulfur mustard (sm), which negatively influences the quality of life. exact pathophysiology of sm-induced itching is unknown. the current study aimed at evaluating the possible association between sm-induced itching and the serum levels of matrix metalloproteinase (mmp)-9 and their endogenous inhibitors, and serum levels of soluble forms of selectins (sl-, sp-, and se-selectins) as adhesion molecules involved in the development of different inflammatory reactions.methods: serum levels of mmp-9, mmp-9/ tissue inhibitors of metalloproteinases (timps), and selectins were measured by the enzyme-linked immunosorbent assay (elisa), and compared between the groups (n=368) with and without itching, and matched control groups (n=126).results: serum levels of mmp-9 were significantly higher in the sm exposed group with itching, compared with that of the group without itching (medians: 894 and 624 pg/ml respectively; p-value =0.034). there was no relationship between the serum levels of mmp-9/timp-1, mmp-9/timp-2, mmp-9/timp-4, and itching in the patients exposed to sm. median serum levels of se- and sl-selectins in the exposed group with itching were higher than those of the exposed group without itching. these differences were statistically insignificant (p-values =0.084 and 0.095, respectively).conclusion: according to the results of the current study, the increased serum levels of mmp-9 and selectins 20 years after exposure may play role in the pathogenesis and persistence of sm-induced itching in the exposed individuals.