Methionine Decholesterolization in Old Hens. ∗ †

Choline has been shown in our previous studies to have a decholesterolizing effect in old hens. 1 Methionine has been found to take part in a reversible reaction with choline in the animal body 2 and to substitute for choline 3 and be effective in lipid metabolism disturbances in the liver of mammals. 4 , 5 It therefore seemed logical to study methionine, just as we have choline and inositol, as a possible decholesterolizing agent in old hens with hypercholesterosis.

Forty-four 2-year-old white leghorn hens were individually caged and fed the standard Texas A & M laying mash. The initial blood lipid levels were determined by the methods of Bloor 6 for total cholesterol, Bloor and Knudson 7 for cholesterol esters, and King 8 for total and inorganic phosphorus.

Methionine, 0.5 g, was placed daily in the gullet of each of 24 of the old hens. One hen died of liver disease. After feeding the methionine for 18 to 29 days, the hens were bled a second time and the blood lipids were again determined, but, as shown in Table I, very little decholesterolization had occurred. The administration of methionine was continued, third bleedings were made after 36 to 51 days, and the bloods chemically analyzed as before.

When random samples of blood showed that the cholesterol levels were singnificantly lowered, the hens were sacrificed and blood collected fro lipid analysis. The aorta, about a quarter gram of heart muscle and a similar mass of liver were individually and accurately weighed, then maceratd with sand and 1 to 3 ether alcohol solution. The extract of each organ was analyzed and the amounts of total cholesterol and cholesterol esters in 100 g of each tissue calculted. Twenty old hens fed as simultaneous controls were also sacrificed and the blood and tissues likewise treatd. The results are set down as controls in Table I.

It is evident that the total blood cholesterol and cholesterol ester levels definitely decreased and the phospholipids rose after the old hens had been given 0.5 g methionine daily for about 3 weeks. After 5 to 7 weeks treatment, significantly lower levels of the blood cholesterol and cholesterol esters were established, and the aorta, heart, and liver showed signifificantly lower lipid levels than those of the control series. Methionine there-fore, seems to act as a decholesterolizing agent in old hens.