Brain development lipid composition

It has been long known that lipid abnormalities are associated with psychosis [5]. For example, abnormal GPL metabolism or altered brain membrane lipid composition is associated with the development of schizophrenia [100], Importantly, the results from an intervention study with long-chain n-3 fatty acids clearly indicate the importance of lipids in the progression of psychosis since the study demonstrated that treatment with long-chain n-3 fatty acids could reduce the risk of progression to psychotic disorder [101]. 

The lipid compositions of plasma membranes, endoplasmic reticulum and Golgi membranes are distinct 26 Cholesterol transport and regulation in the central nervous system is distinct from that of peripheral tissues 26 In adult brain most cholesterol synthesis occurs in astrocytes 26 The astrocytic cholesterol supply to neurons is important for neuronal development and remodeling 27 The structure and roles of membrane microdomains (rafts) in cell membranes are under intensive study but many aspects are still unresolved 28... 

It is difficult to alter the composition of the brain lipid fatty acids. Reduction of brain EFAs in young animals has been successfully achieved by feeding EFA-deficient diets to the mother during pregnancy. Reduction of brain EFAs using this technique was associated with retardation of brain development (Caldwell Churchill, 1966 Paoletti Galli, 1972 Sinclair Crawford,... 

Each phospholipid class in a given tissue has a characteristic fatty acid composition. Though the same fatty acid may be present in a number of lipids, the quantitative fatty acid composition is different for each class of lipids and remains fairly constant during the growth and development of the brain. A typical distribution profile of the major fatty acids in rat brain phospholipids is given in Table 3.1. Not only do the phosphoglycerides differ in the structure of the polar head groups, or phospholipid... 

Central nervous system myelin is enriched in certain lipids. Table 4-1 lists the composition of bovine, rat, and human myelin compared to bovine and human white matter, human gray matter, and rat whole brain [1] (see Ch. 3). While there are no absolutely myelin-specific lipids, cerebroside (galactosyl ceramide) is the most typical of myelin. With the exception of early development,... 

By feeding nutritionally adequate diets, dietary intake of 18 2n-6, 18 3n-3, or the proportion of 18 2n-6 to 18 3n-3, particularly during development, has been shown to influence the content of long-chain polyunsaturated fatty acids in membrane lipids by changing the composition of the whole brain, oligodendrocytes, myelin, astrocytes mitochondrial, microsomal, and synaptosomal membrane (Bourre et al., 1984 Foot et al., 1982 Lamptey Walker, 1976 Tahin et al., 1981). Feeding diets with a 18 2n-6 to 18 3n-3 fatty acid ratio between 4 1 and 7 1 to rats from birth to 1, 2, 3, and 6 wk of... 

In this chapter, our intent is to review the rapid changes that take place in the cerebral cortex of n-3 fatty acid-deficient monkeys when their diet is subsequently supplied with ample dietary n-3 fatty acids. Juvenile rhesus monkeys who had developed n-3 fatty acids deficiency since intrauterine life were repleted with a fish-oil diet rich in n-3 fatty acids, DHA, and 20 5n-3 (eicosapentaenoic acid, EPA). The fatty acid composition was determined for the lipid classes of plasma and erythrocytes and for the phospholipid classes and molecular species of frontal cortex samples obtained from serial biopsies and at the time of autopsy. From these analyses, the half-lives ofDHA and EPA in the phospholipids of plasma, erythrocytes, and cerebral cortex were estimated. The deficient brain rapidly regained a normal or even supernormal content ofDHA with a reciprocal decline in n-6 fatty acids, demonstrating that the fatty acids of the gray matter of the brain turn over with relative rapidity under the circumstances of these experiments. 

Suzuki H, Park S J, Tamura M, Ando S. Effect of the long-term feeding of dietary lipids on the learning ability, fatty acid composition of brain stem phospholipids and synaptic membrane fluidity in adult mice a comparison of sardine oil diet with palm oil diet. Meeh Ageing Develop 1998 101 119-128. 

Enslen M, Milon H, Malnoe A. Effect of low intake of n-3 fatty acids during development on brain phospholipid fatty acid composition and exploratory behavior in rats. Lipids 1991 26(3) 203-208. 

A chloroform/methanol/water system is appropriate for the separation of an acidic fraction. If the solvent compositions are not optimized, the phospholipids and glycolipids are eluted at the solvent front or in the column contents. When we chose a suitable solvent, acidic phospholipids (phosphatidic acid, phosphatidylserine, phosphatidylinositol, lysophosphatidyl-inositol, and lysophosphatidylserine) were satisfactorily separated between the solvent front and the column contents (Fig. 2A). Samples (2 mg each) of the acidic fraction of human brain lipids was applied to TC-CCC by using the chloroform/methanol/water (5 4 3) solvent system. Aliquots of each fraction were spotted and developed by HPTLC. 

From the chemical point of view, the blood-brain barrier did not appear until the late stages of development, at the onset of function. Lipids were absent from the neural tube. They appeared fairly early in fetal life and their concentration in brain tissue increased steadily until the composition found in adult tissue was reached. It was already known that the appearance and increase in amounts of lipids followed fairly rigid timetables, which changed from species to species, but were fairly consistent in each species. Various lipids... 

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