Relationship between fatty acid composition of erythrocytes and susceptibility to vitamin E deficiency

The effect of dietary change on in vitro erythrocyte haemolysis, skin lesions and alopecia in common marmosets (Callithrix jacchus)

1. The effect of dietary change on common marmosets (Callithrix jacchus) exhibiting high in vitro erythrocyte haemolysis, skin lesions and alopecia was investigated. 2. The experimental diet was low in lipid, high in vitamin E and was devoid of n-3 long chain polyunsaturated fatty acids. 3. There were significant increases in the concentrations of plasma alpha-tocopherol (vitamin E) (P less than 0.05), all-trans retinol (vitamin A) (P less than 0.001) and total lipid (P less than 0.025), and a reduction in fibrinogen (P less than 0.02) concentration and neutrophil count (P less than 0.02). 4. Moreover, the mean in vitro erythrocyte haemolysis declined from an initial value of 64% to less than 2%, and there was a regression of skin lesions and alopecia with complete fur regrowth. 5. The amelioration of the conditions appear to be due to high circulating vitamin E which provided protection against oxidative stress, and the correction of membrane n-6:n-3 balance.

Glutathione peroxidase activity and erythrocyte stability in calves differing in selenium and vitamin E status

1. Glutatione peroxidase activity (EC 1.11.1.9) and erythrocyte stability were measured in Friesian bull calves which were given for 36 weeks semi-purified diets either adequate or low in selenium or vitamin E or both. 2. Dietary Se or vitamin E content had no effect on growth rate and haematlogical values. None of the calves exhibited clinical deficiency symptoms and serum aspartate amino transferase (EC 2.6.1.1) and creatine phosphokinase (EC 2.7.3.2) activities remained normal. Heart and skeletal muscles of all calves appeared macroscopically and microscopically normal ato autopsy. 3. Glutathione peroxidase activity in plasma, blood and other tissues, except the testis, was significantly lower in calves receiving low dietary Se but was independent of dietary vitamin E content. 4. Plasma vitamin E levels decreased rapidly and to very low levels in calves given low vitamin E diets irrespective of the Se content of the diet. 5. A low dietary vitamin E intake increased the susceptibility of erythrocytes to auto- and peroxidative haemolysis whereas a low Se intake in the presence of adequate vitamin E did not. However, erythrocytes from calves receiving low Se and low vitamin E were more susceptible to peroxidative haemolysis than erythrocytes from calves receiving low vitamin E and adequate Se. The effect of dietary vitamin E content on osmotic haemolysis induced by hypotonic saline was variable. 6. The results suggest that measurement of blood glutathione peroxidase activity and the susceptibility of erythrocytes to auto- or peroxidative haemolysis could be used for the differential diagnosis of subclinical Se and vitamin E deficiency in ruminants.