Algal Derived Functional Lipids and their Role in Promoting Health

Abstract

Algae are organisms with an enormous biodiversity and contain manifold fatty acid molecular structures and ratios. This chapter presents information about the structure and distribution of fatty acids in algae whether microalgae or macroalgae. The parameters affecting lipid and fatty acid contents as well as distribution are also discussed. Methods for isolation and purification of fatty acids from algae to obtain highly pure fatty acid or fatty acid fractions with good overall yields are presented. Algal fatty acids are known as sources of bioactive compounds for health promotion and wellness. Lipid fractions and fatty acids act as actives or additives for cosmeceutical applications. For health promotion, preventive effects of n-3 polyunsaturated fatty acids on cardiovascular disease, metabolic syndrome and cancer are discussed. The role of n-3 fatty acids in cancer therapy and antiviral activities of lipids are also exposed. Furthermore, potential commercial application domains and concepts are discussed in this chapter.

Contribution of n-3 Long-Chain Polyunsaturated Fatty Acids to the Prevention of Breast Cancer Risk Factors

“…The antiproliferative and pro-apoptotic effects of n-3 LC-PUFAs have been extensively studied in many human cancer cell lines and using purified n-3 LC-PUFAs, mainly DHA [16][17][18][19][20]. However, understanding the cellular and molecular mechanisms of the anticancer effect of n-3 LC-PUFAs remains an important area of current research, and despite numerous efforts, it remains difficult to identify a clear pattern of the involved mechanisms.…”

“…In various breast cancer cell lines, DHA acted as an anti-proliferative agent by lengthening the cell cycle, leading to cell cycle arrest at the G1 or G2/M phase (Figure 1) [21]. Increased sensitivity to reactive oxygen species (ROS) in DHA-treated cells, especially through downregulation of superoxide dismutase 1 (SOD1) and glutathione peroxidase 1 (GPX1), has also been invoked as an explanation for the antiproliferative effect of DHA [16,18,22]. In addition, DHA was also reported as inducing the expression and nuclear translocation of the oxidative stress sensitive transcription factor, NFE2L2/Nrf2, and to increase the expression of oxidative stress-induced growth inhibitor 1 (OSGIN1) in MCF-7 and Hs578T breast cancer cells (Figure 1) [23].…”

“…Apoptosis was induced by DHA, and in a lesser extent by EPA, in cancer cells through impairment of the activity of protein kinase, Akt/PKB; p53 activation; increased caspase-3, caspase-9, and Bax pro-apoptotic enzyme levels or activity; and decreased survival and Bcl-XL, with DHA or EPA concentration ranging from 10 to 200 µM (reviewed in: [16,21]). The inactivation of the PI3K/Akt pathway is the main apoptosis pathway mentioned in the literature (Figure 1) [16,21]. For example, Akt signaling was inhibited by DHA in MCF-7 cells, leading to decreased fatty acid synthase (FASN) expression and reduced cell proliferation [29].…”

“…Several studies have been conducted in animal models of chemically-induced tumors or tumor xenografts that reported antiproliferative and pro-apoptotic effects of DHA or dietary fats (reviewed in: [16,[35][36][37][38]). In addition, Wang et al recently reported the induction of autophagy in breast tumor cells from xenografted mice administered intragastrically with DHA-monoglyceride daily [27].…”

“…Thus, fat-1 transgenic mice are able to produce n-3 fatty acids from the n-6 ones, leading to abundant n-3 fatty acids with reduced levels of n-6 fatty acids in their organs and tissues, without the need of a dietary n-3 supply [39,40]. These studies mainly focused on colorectal cancer and colitis-associated cancer [38], but have also targeted other types of cancers, including breast cancer [16,40,41]. For example, Zou et al showed the protective effect of n-3 LC-PUFAs (especially 15-hydroxy eicosapentaenoic acid, 17-hydroxy docosahexaenoic acid, and prostaglandin E3) against breast cancer in fat-1 mice versus wild-type mice [42].…”