Nitrite from inflammatory cells--a cancer risk factor in ulcerative colitis?
Elevated levels of luminal nitrite and a lowered luminal pH were found in 77 percent of patients with acute ulcerative colitis. No luminal nitrite was found in healthy control subjects. Nitrites are a secretory product of activated macrophages and neutrophils of the lamina propria, whereas the lowered luminal pH is due to diminished bicarbonate formation by impaired colonocytes. A hypothesis is put forward that nitrites, lowered pH, and bacterial amines are conducive to formation of carcinogenic n-nitroso compounds, which reflect a cancer risk in patients with ulcerative colitis dependent on the type and extent of inflammatory cell activation as well as metabolic impairment of colonic epithelial cells.
Roediger
W E
WE
Department of Surgery, University of Adelaide, Australia.
Lawson
M J
MJ
Radcliffe
B C
BC
D000818:Animals; D003093:Colitis, Ulcerative / Q000378:metabolism*; D003106:Colon / Q000378:metabolism / Q000382:microbiology; D003110:Colonic Neoplasms / Q000209:etiology*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008264:Macrophages / Q000378:metabolism*; D009504:Neutrophils / Q000378:metabolism*; D009573:Nitrites / Q000378:metabolism*; D009602:Nitrosamines / Q000378:metabolism; D012307:Risk Factors
D009573:Nitrites; D009602:Nitrosamines