The role of sodium thiocyanate supplementation during dextran sodium sulphate-stimulated experimental colitis

Abstract

Ulcerative colitis is a condition characterised by the infiltration of leukocytes into the gastrointestinal wall. Leukocyte-MPO catalyses hypochlorous acid (HOCl) and hypothiocyanous acid (HOSCN) formation from chloride (Cl -) and thiocyanous (SCN -) anions, respectively. While HOCl indiscriminately oxidises biomolecules, HOSCN primarily targets low-molecular weight protein thiols. Oxidative damage mediated by HOSCN may be reversible, potentially decreasing MPO-associated host tissue destruction. This study investigated the effect of SCNsupplementation in a model of acute colitis. Female mice were supplemented dextran sodium sulphate (DSS, 3% w/v) in the presence of 10 mM Clor SCNin drinking water ad libitum, or with salts (NaCl and NaSCN only) or water only (controls). Behavioural studies showed mice tolerated NaSCN and NaCl-treated water with water-seeking frequency. Ionexchange chromatography showed increased fecal and plasma SCNlevels in thiocyanate supplemented mice; plasma SCNreached similar fold-increase for smokers. Overall there was no difference in weight loss and clinical score, mucin levels, crypt integrity and extent of cellular infiltration between DSS/SCNand DSS/Clgroups. Neutrophil recruitment remained unchanged in DSS-treated mice, as assessed by fecal calprotectin levels. Total thiol and tyrosine phosphatase activity remained unchanged between DSS/Cland DSS/SCNgroups, however, colonic tissue showed a trend in decreased 3-chlorotyrosine (1.5-fold reduction, p<0.051) and marked increase in colonic GCLC, the rate-limiting enzyme in glutathione synthesis. These data suggest that SCNadministration can modulate MPO activity towards a HOSCN-specific pathway, however, this does not alter the development of colitis within a DSS murine model.

The Association Between Environmental Perchlorate, Nitrate, and Thiocyanate Exposure and Oral Pain in NHANES

“…Firstly, thiocyanate is a metabolite of cyanide in tobacco and is detectable in saliva ( 20 , 21 ) and in the oral mucosa ( 6 ), which could influence the oral microenvironment. Secondly, the thiocyanate may have an antibacterial and antioxidative role for cardiovascular diseases and respiratory viral infections ( 22 , 23 ), but may aggravate the inflammation responses in the autoimmune disease and gastrointestinal disease ( 24 , 25 ). Therefore, its effect on oral health could be related to the level of thiocyanate or the comorbidities.…”

Halogenation Activity of Mammalian Heme Peroxidases

“…As SCN − is very rapidly oxidized by HOCl [69] and HOBr [70], SCN − can efficiently compete with other substrates for these powerful hypohalous acids. As addressed in several reports, SCN − is able to protect cell and tissue components from the devastating actions of MPO-generated HOCl [71][72][73][74].…”