Effects of different dietary fatty acids on the fatty acid compositions and the expression of lipid metabolic-related genes in mammary tumor tissues of rats.
In this study, the effects of dietary fatty acids on the fatty acid compositions and lipid metabolic-related genes expression in N-methyl-N-nitrosourea (MNU)-induced rat mammary carcinogenesis were evaluated. The 50-day-old female Sprague-Dawley rats were intervened by different dietary fats (15% wt/wt), including saturated fatty acid (SFA), monounsaturated fatty acid (MUFA), n-6 polyunsaturated fatty acid (PUFA), n-3 PUFA, 1:1 n-6/n-3, 5:1 n-6/n-3, 10:1 n-6/n-3, and 1:2:1 S/M/P (1:1 n-6/n-3), alone or in combination with MNU. There was no mammary tumor occurrence in the control and MNU-treated n-3 PUFA groups after 18 wk. n-3 PUFA diet retarded the weight growth of rats. 1:1 n-6/n-3 diet significantly reduced the MNU-induced tumor incidence and tumor multiplicity compared with SFA, MUFA, n-6 PUFA, 5:1 n-6/n-3, 10:1 n-6/n-3 and 1:2:1 S/M/P diets (42.86% vs. 83.33%-92.31%, 0.79 vs. 2.62-2.85, P < 0.01). Additionally, 1:1 n-6/n-3 diet substantially increased cis-5,8,11,14,17-eicosapentaenoic acid and cis-4,7,10,13,16,19-docosahexaenoic acid levels, whereas it decreased C20:4 level and the mRNA expressions of fatty acid synthase, Cyclooxygenase-2 (COX-2), and 5-lipoxygenase (5-LOX) in mammary tissues (P < 0.05). These results suggest that 1:1 n-6/n-3 in the diet is effective in the prevention of mammary tumor development by increasing the n-3 PUFA content and reducing the expression of lipid metabolic-related genes.
Wei
Na
N
Department of Nutrition and Food Hygiene, Chongqing Key Laboratory of Nutrition and Food Safety, Third Military Medical University, Chongqing, PR China.
Wang
Bin
B
Zhang
Qian-Yong
QY
Mi
Man-Tian
MT
Zhu
Jun-Dong
JD
Yu
Xiao-Ping
XP
Yuan
Jia-Ling
JL
Chen
Ka
K
Wang
Jian
J
Chang
Hui
H
D000818:Animals; D001094:Arachidonate 5-Lipoxygenase / Q000235:genetics; D016718:Arachidonic Acid / Q000378:metabolism; D051546:Cyclooxygenase 2 / Q000235:genetics; D004041:Dietary Fats / Q000008:administration & dosage*; D064429:Fatty Acid Synthases / Q000235:genetics; D005227:Fatty Acids / Q000032:analysis*; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage; D043371:Fatty Acids, Omega-6 / Q000008:administration & dosage; D005260:Female; D008321:Mammary Glands, Animal / Q000737:chemistry; D008325:Mammary Neoplasms, Experimental / Q000737:chemistry / Q000378:metabolism / Q000517:prevention & control*; D051381:Rats; D017207:Rats, Sprague-Dawley; D015430:Weight Gain
D004041:Dietary Fats; D005227:Fatty Acids; D015525:Fatty Acids, Omega-3; D043371:Fatty Acids, Omega-6; D016718:Arachidonic Acid; D001094:Arachidonate 5-Lipoxygenase; D051546:Cyclooxygenase 2; D064429:Fatty Acid Synthases