Where Is Dha Found

In mammals, DHA is found in high amounts in three types of cellular membranes, those of the rod outer segment (ROS) (Wiegand & Anderson, 1983), synaptosomes (Breckenridge et al., 1972) and sperm (Neill & Masters, 1973). In these cells, DHA can represent more than 50% of the total membrane phospholipid acyl chains (Salem et al., 1986). At such high levels, much of the DHA exists as di-DHA phospholipid species (Miljanich et al., 1979). In these tissues, DHA is tenaciously retained at the expense of other fatty acids (Salem et al., 1986) and so levels are kept constantly high and are relatively unresponsive to dietary fluctuations. In all other tissues, DHA is found at much lower levels. In these cells, DHA exists primarily in hetero acid phospholipids with the sn-1 chain composed mainly of the saturated fatty acids palmitic or stearic acid and the sn-2 chain DHA (Anderson & Sperling, 1971). In leukocytes, DHA represents about 2-5% of total fatty acids (Fritsche & Johnston, 1990; Hinds & Sanders, 1993; Yaqoob et al., 1995). This value is dependent on diet (Fritsche & Johnston, 1990; Hinds & Sanders, 1993; Yaqoob et al., 1995) and increases with age (Huber et al., 1991). DHA is found predominantly in phosphatidylethanolamine (PE) and phosphatidylserine (PS), but it is also present in other phospholipid classes, including phosphatidylcholine (PC) and phosphatidylinositol (PI) (Robinson et al., 1993; Salem et al., 1986; Tiwari et al., 1988; Zerouga et al., 1996). Omega-3 fatty-acid-rich diets can increase the amount of DHA two to three fold in all phospholipid species of normal lymphocytes (Robinson et al., 1993), and can significantly increase the DHA content of phospholipids in leukemia and lymphoma cells grown in vivo as ascites (El Ayachi et al., 1990; Jenski et al., 1993). Culture of leukemia cells in DHA-enriched medium can increase the DHA content of phospholipids severalfold (Chow et al., 1991; Zerouga et al., 1996). For example, in our laboratory, DHA was incubated with T27A leukemia cells in culture, where it was initially incorporated into PE. DHA levels in PE of the cultured T27A cells increased from 3.3% of the total fatty acids in control cells to 21% after 12 h of incubation in DHA and 29% after 48 h of incubation (Zerouga et al., 1996). By comparison, PC-DHA rose from undetectable levels to 5.9% at 12 h and 9.6% at 24 h. After 48 h, T27A cells exhibited new DHA incorporation into PE about 2.7 times greater than into PC. When the 2.1-fold excess of PC over PE is factored in, it was estimated that a new incoming DHA prefers PE over PC by about 5.7 times. In a variety of cell types, DHA has been shown to be rapidly incorporated primarily into the plasma membrane of synapto-somes and mitochondria (Suzuki et al., 1997). Once incorporated from the diet into cellular membranes, DHA is tenaciously retained at the expense of other fatty acids (Salem et al., 1986).

5 Ways To Get Rid Of The Baby Fat

5 Ways To Get Rid Of The Baby Fat

Many women who have recently given birth are always interested in attempting to lose some of that extra weight that traditionally accompanies having a baby. What many of these women do not entirely realize is the fact that breast-feeding can not only help provide the baby with essential vitamins and nutrients, but can also help in the weight-loss process.

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