| It is established that dietary ω3 polyunsaturated fatty acids (ω3 PUFA) protect against cardiovascular disease (CVD). One way that ω3 PUFAs act is by altering the activity of proteins responsible for cardiac contraction strength and frequency. However, the underlying mechanism is not known. Study A was designed to determine whether the ω3 PUFA, docosahexaenoic acid (DHA, 22:6ω3), reduces contraction amplitude in adult guinea pig cardiomyocytes, and whether those decreases are due to DHA-mediated changes in intracellular cAMP formation. Cardiomyocytes were exposed to electric field stimulation (100V, 2 Hz, 2 msec) to evoke regular contractions at 37°C. Although the risk of CVD is increased with elevated serum lipid levels including both cholesterol and triacylglycerol (TAG), it is known that ω3 PUFAs reduce only the latter. In contrast, phytosterols are effective cholesterol reducing agents. Study B was designed to investigate the effects of a novel dietary supplement, ω3 PUFA-esterified phytosterols (PSω3) on serum lipid levels. (Abstract shortened by UMI.)... |
