title: Increased intake of n-3 polyunsaturated fatty acids elevates the level of apoptosis in the normal sigmoid colon of patients polypectomized for adenomas/tumors.
abstract: To clarify preventive effects of n-3 polyunsaturated fatty acids (PUFAs) against colorectal carcinogenesis, we performed a dietary intervention in patients polypectomized for colorectal adenomas/tumors. For the former the following dietary advice was given: (1) decrease intake of fat from 30 to 20% of the total; (2) decrease consumption of n-6PUFAs containing foods, and increase intake of n-3 PUFAs for 2 years. For the comparison group only decreased intake of fat (30-20%) was recommended. Samples of normal sigmoid colon mucosa, obtained by colonoscopic check once a year during the intervention period, were used to investigate COX-2, cell proliferation (Ki67 expression), p53, Bcl-2 and Bax by immunostaining and determine the apoptosis index (AI) by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-nick end labeling (TUNEL) in 21 and 20 patients in experimental and comparison groups, respectively, who completed the 2 years of the intervention. After 24 months, the AI and positive cells of Bax and the ratio of Bax/Bcl-2 in normal sigmoid colon mucosa for the experimental group was significantly increased, whereas this change was not found in comparison group. These observations demonstrated for the first time that increased intake of n-3 PUFAs promotes apoptosis of normal colon mucosa in human which is related to effect on Bax or the balance of Bax and Bcl-2.
authors.affiliation: Department of Health Promotion and Preventive Medicine, Nagoya City University Graduate School of Medical Sciences, Mizuho-ku, Nagoya, Japan.
authors.forename: Jinglei
authors.initials: J
authors.lastname: Cheng
authors.forename: Kumiko
authors.initials: K
authors.lastname: Ogawa
authors.forename: Kiyonori
authors.initials: K
authors.lastname: Kuriki
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Yokoyama
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kamiya
authors.forename: Kyoji
authors.initials: K
authors.lastname: Seno
authors.forename: Harumi
authors.initials: H
authors.lastname: Okuyama
authors.forename: Jingwen
authors.initials: J
authors.lastname: Wang
authors.forename: Chenhong
authors.initials: C
authors.lastname: Luo
authors.forename: Toshiko
authors.initials: T
authors.lastname: Fujii
authors.forename: Hiromitsu
authors.initials: H
authors.lastname: Ichikawa
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Shirai
authors.forename: Shinkan
authors.initials: S
authors.lastname: Tokudome
mesh_terms: D000236:Adenoma / Q000378:metabolism / Q000473:pathology*; D017209:Apoptosis; D002455:Cell Division; D003106:Colon / Q000378:metabolism / Q000473:pathology*; D003110:Colonic Neoplasms / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*; D015525:Fatty Acids, Omega-3; D005231:Fatty Acids, Unsaturated / Q000493:pharmacokinetics*; D006801:Humans; D007150:Immunohistochemistry; D020287:In Situ Nick-End Labeling; D009092:Mucous Membrane / Q000378:metabolism / Q000473:pathology; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D014280:Triglycerides / Q000493:pharmacokinetics*; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism; D051028:bcl-2-Associated X Protein
chemical_list: C494826:BAX protein, human; D015525:Fatty Acids, Omega-3; D005231:Fatty Acids, Unsaturated; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D014280:Triglycerides; D016159:Tumor Suppressor Protein p53; D051028:bcl-2-Associated X Protein; C077446:Pikasol