Lipid peroxidation levels in peptic ulcer and gastric carcinoma.

Pept ic u lce rs and carc inomas a re two major pa tho log ica l condi t ions o f the gas t ro in tes t ina l t r ac t . Mal ignanc ies o f the G.I tract are relatively resistant to radiation therapy and benef i t f rom chemotherapy remains modes t , whereas an e f fec t ive ra t iona l the rapy s t i l l r emains e lus ive in cases of gastro duodenal ulceration. One of the common denomina tors p roposed in genes i s o f these d i seases i s f ree rad ica l s t ress . F ree rad ica l s a re h igh ly reac t ive molecu les , which a re p roduced as a byproduct of metabol ism (1) . A react ive free rad ica l genera ted in the body reac t s wi th non-radical and results in free radical chain reac t ion lead ing to fo rmat ion of new f ree radicals. If the defence mechanism of body fails to combat them, these free radicals pose a threat of injuring tissues by reacting with ce l l l ip ids . L ip ids in the ce l l membrane undergo degradation to form hydroperoxides. Po lyunsa tura ted fa t ty ac ids , PUFA, a re especially liable to lipid peroxidation. Lipid hydroperoxides decompose to form a variety of p roduc ts inc lud ing malondia ldehyde (MDA). MDA was used as an indicator to assess oxidative damage of cells and tissues (2) and prof i le of ant ioxidant defence was s tud ied as superox ide d i smutase and ca ta lase ac t iv i t i es in the above s ta ted s t u d i e s . Thi r ty cases of pept ic u lcer proved by endoscopy (both duodenal and gastric ulcer) and an equal number of gas t r ic carc inoma were se lec ted f rom the ou t pa t ien t Department of Medicine and Gastroenterology, Univers i ty Hosp i ta l , Banaras Hindu Univers i ty , Varanas i . Gas t r ic ca rc inoma patients were also confirmed by histopathological examinat ion of the biopsy. Fi f teen heal thy age and sex-matched subjects were included following their informed consent to provide as con t ro l cases . Blood samples were collected form the antecubital vein and serum was separa ted . Leve ls o f malondia ldehyde (MDA) in the se rum were examined in pa t ien t s o f pep t ic u lce r and gas t r i c carcinoma and referred to those in heal thy cont ro l subjec ts . Al l the pa t ien ts inc luded in the s tudy underwent endoscopic examina t ion . Biopsy f rom the pa t ien t s o f gastric carcinoma, in addition, was taken for h is topa thologica l examinat ion .