Effect of polyunsaturated fatty acids and phospholipids on ( sup 3 H)-vitamin E incorporation into pulmonary artery endothelial cell membranes

Journal Article · Sat Dec 01 04:00:00 EST 1990 · Journal of Cellular Physiology; (USA)

DOI:https://doi.org/10.1002/jcp.1041450324· OSTI ID:6061557

Sekharam, K M; Patel, J M; Block, E R ^[1]

---

1. Univ. of Florida College of Medicine, Gainesville (USA)

Vitamin E, a dietary antioxidant, is presumed to be incorporated into the lipid bilayer of biological membranes to an extent proportional to the amount of polyunsaturated fatty acids or phospholipids in the membrane. In the present study we evaluated the distribution of incorporated polyunsaturated fatty acids (PUFA) and phosphatidylethanolamine (PE) in various membranes of pulmonary artery endothelial cells. We also studied whether incorporation of PUFA or PE is responsible for increased incorporation of (3H)-vitamin E into the membranes of these cells. Following a 24-hr incubation with linoleic acid (18:2), 18:2 was increased by 6.9-, 9.2-, and 13.2-fold in plasma, mitochondrial, and microsomal membranes, respectively. Incorporation of 18:2 caused significant increases in the unsaturation indexes of mitochondrial and microsomal polyunsaturated fatty acyl chains (P less than .01 versus control in both membranes). Incubation with arachidonic acid (20:4) for 24 hr resulted in 1.5-, 2.3-, and 2.4-fold increases in 20:4 in plasma, mitochondrial, and microsomal membranes, respectively. The unsaturation indexes of polyunsaturated fatty acyl chains of mitochondrial and microsomal membranes also increased (P less than .01 versus control in both membranes). Although incubations with 18:2 or 20:4 resulted in several-fold increases in membrane 18:2 or 20:4 fatty acids, incorporation of (3H)-vitamin E into these membranes was similar to that in controls. Following a 24-hr incubation with PE, membrane PE content was significantly increased, and (3H)-vitamin E incorporation was also increased to a comparable degree, i.e., plasma membrane greater than mitochondria greater than microsomes. Endogenous vitamin E content of the cells was not altered because of increased incorporation of PE and (3H)-vitamin E.

• OSTI ID: 6061557
• Journal Information: Journal of Cellular Physiology; (USA), Journal Name: Journal of Cellular Physiology; (USA) Vol. 145:3; ISSN 0021-9541; ISSN JCLLA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
550501 -- Metabolism-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ANIMAL TISSUES
ARACHIDONIC ACID
ARTERIES
BIOCHEMICAL REACTION KINETICS
BLOOD VESSELS
BODY
CARBOXYLIC ACIDS
CARDIOVASCULAR SYSTEM
CELL CONSTITUENTS
CELL MEMBRANES
ENDOTHELIUM
ESTERS
HYDROGEN COMPOUNDS
ISOTOPE APPLICATIONS
KINETICS
LINOLEIC ACID
LIPIDS
LUNGS
MEMBRANES
METABOLISM
MICROSOMES
MITOCHONDRIA
MONOCARBOXYLIC ACIDS
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
ORGANOIDS
ORGANS
PHOSPHOLIPIDS
REACTION KINETICS
RESPIRATORY SYSTEM
RIBOSOMES
TISSUES
TRACER TECHNIQUES
TRITIUM COMPOUNDS
VITAMIN E
VITAMINS