Biochemical Properties of Lipid Composition of Lipoproteins in Fish of Different Ecological Groups, Rainbow Trout Salmo irideus L. and Whitefish Coregonus lavaretus L.

We have studied the lipid composition of low- and high-density lipoproteins from the blood sera of female rainbow trout Salmo irideus L. and whitefish Coregonus lavaretus L. Phospholipids prevail in all lipoprotein fractions, and phosphatidylcholine is dominant among them. Species-specific features of lipid fractions depend on ecological conditions under which these fish exist: rainbow trout is an almost domesticated species, whereas whitefish is a component of the natural ichthyofauna. The sera of these species contains lipoprotein groups specific for other animals; however, high-density lipoproteins prevail in fish.     

Age-Related Features of Cataractogenesis in Salmon Fry. 2. Biochemical Features of Lens during Cataractogenesis

We studied biochemical features of the lipid and phospholipid composition and patter of fatty acid spectra in lenses of one and two year old salmons bearing cataracts. The lipid complex of lenses of diseased fish underwent significant changes. Cataractogenesis was accompanied by enhanced free radical oxidation and accumulation of malone dialdehyde in lenses of salmons of various ages. The intensification of oxidative processes was synchronized with the decreased level of antioxidant protection (reduced glutathione, vitamins A and E). The activity of Ca²⁺-dependent proteolytic enzymes in lenses was determined and its decrease in the case of cataract was shown.     

Age-Related Features of Cataractogenesis in the Salmon Fry. 1. Lipid Composition of Lens during Normal Development

This papers opens a series of publications on the mechanisms of cataractogenesis in the salmon fry. Biochemical features of normal lens development and cataractogenesis in fry of different age and age-related dynamics of the liver lipid composition during upon cataractogenesis will be dealt with, since lipids are most intensely synthesized in the liver, from where they are transported in the lens. Here, we describe the dynamics of lens lipid composition in the salmon fry, including the total lipid content and dynamics of individual classes. The data are analyzed on the fatty acid spectrum of the salmon fry lens, as compared to the human lens.     

Patterns of Biochemical Differentiation in Ontogenesis

Here we review original data on biochemical differentiation mechanisms. The patterns of the preprogrammed metabolism of the embryo are studied by comparing biochemical mechanisms in undifferentiated embryonic tissues in the course of differentiation and during the terminal establishment of a specialized tissue. This review is composed of three main sections corresponding to the specifity of biochemical differentiation. The first section covers the material on time-related isozyme pattern during skeletal muscle differentiation in a loach (a teleostean fish). The second section presents the data on incorporated activation, i.e., the appearance of a functional relationship between contractile proteins biosynthesis and the systems of glycogenolysis and glycogen synthesis during the development of chick embryo muscle. The third section covers the data on liver differentiation, the formation of the glycogen organelle with embedded enzymes of glycogen synthesis, and the degradation of chick and rat embryos during development.     

Age-Related Features of Cataractogenesis in Salmon Fry. III. Age-Related Dynamics of Liver Lipid Composition during Cataractogenesis

When studying the cataract pathogenesis in salmon fry, we found changes in the content of individual; phospholipid fractions and fatty acid composition in the liver of diseased and healthy fish. The age-related changes correlated with the increased antioxidant activity and decreased liver content of malondialdehyde.