The Growth-Inhibiting Effects of Beef Fatty Acids on MCF-7 Cells Are Influenced Mostly by the Depot Location and Inconsistently by the Biohydrogenation Intermediate Content
Vahmani, P., Rolland, D.C., Gzyl, K.E., Baines, D.D.S., Dugan, M.E.R. (2018). The Growth-Inhibiting Effects of Beef Fatty Acids on MCF-7 Cells Are Influenced Mostly by the Depot Location and Inconsistently by the Biohydrogenation Intermediate Content. Lipids, [online] 53(7), 699-708. http://dx.doi.org/10.1002/lipd.12085
Plain language summary
In cattle, dietary polyunsaturated fatty acids (PUFA) are toxic to rumen bacteria. To cope, rumen bacteria convert PUFA to less toxic saturated fatty acids through a process known as biohydrogenation. Under certain conditions, biohydrogenation intermediates (BHI) like conjugated linoleic acid (CLA) can be produced and accumulate in beef. The types and amounts of BHI accumulating depend mostly on cattle diets and tissue locations. Although many studies have examined the anti-cancer effects of CLA, few studies have reported the effects of BHI in their natural form found in beef fat. The present study compared the effects of beef kidney- or back-fat with low- or high- levels of BHI on human breast cancer cell growth. BHI were readily incorporated into cells, but higher BHI did not consistently inhibit growth. Culturing cancer cells with either low- or high-BHI kidney fat did not inhibit growth. Growth was inhibited by low-BHI back-fat, and further inhibited by high-BHI back-fat. Anti-cancer effects of BHI are, therefore, not all equal, and can be influenced by other classes of fatty acids found in beef fat.
Biohydrogenation intermediates (BHI) including conjugated linoleic acid (CLA) isomers are formed during ruminal biohydrogenation of polyunsaturated fatty acids (PUFA) in ruminants. Although many studies have examined the anticarcinogenic effects of CLA, few studies have reported the anticarcinogenic properties of BHI in their natural form found in dairy and beef fats. The present study compared the growth-inhibitory effects of fatty acids from beef perirenal fat (PRF) or subcutaneous fat (SCF) with low or high levels of BHI in MCF-7 human breast cancer cells. Cells were exposed for 72 h to media containing increasing doses (50 to 400 μM) of different beef fat treatments. Fatty-acid analysis showed that BHI were readily incorporated into cell phospholipids (PL) in a treatment-dependent manner, but higher BHI in PL did not consistently inhibit growth. Culturing with low-BHI PRF or high-BHI PRF did not lead to growth inhibition, but low-BHI SCF inhibited growth, and inhibition was further increased by high-BHI SCF. Other classes of fatty acids may, therefore, be interacting with BHI resulting in differential effects on growth inhibition in human breast cancer cells.