Fish oil suppresses angiogenesis, reduces cell proliferation and DNA damage in rat mammary carcinogenesis

SummaryBackground & aimsThe current study was designed to evaluate the effect of dietary fish oil and corn oil on carcinogen-induced DNA damage, cell proliferation and angiogenesis in female Sprague-Dawley rats.MethodsRats were treated with 7,12-dimethylbenz(α)anthracene (DMBA) (0.5 mg/0.2 ml corn oil/100 g body weight) by a tail vein injection. Rats were fed either fish oil or corn oil (0.5 ml/day/rat) by oral gavage. DNA Damage, proliferating cell nuclear antigen labeling index (PCNA-LI) and expression of vascular endothelial growth factor (VEGF) and microvessel density (MVD) of the mammary tissue were included in this study.ResultsTissue levels of both 8-hydroxy-2′deoxyguanosine (8-OHdG), a marker of DNA damage and DNA repair enzyme (PARP-1) were significantly reduced (P = 0.00000006) in the fish oil-treated group, and increased (P = 0.00000006) in the corn oil-treated group when compared to carcinogen counterpart. Furthermore, PCNA-LI, VEGF expressions and the MVD values were lower in fish oil-treated group (P = 0.000078; P = 0.000032; P = 0.000000005 respectively) and higher (P = 0.000027; P = 0.00004; P = 0.0000000003 respectively) in corn oil-treated group when compared to carcinogen control.ConclusionsOur results indicate that fish oil protects against carcinogen-induced DNA damage, cell proliferation and angiogenesis.