Carbohydrates experimental animal studies

The results of many studies (Perin et al, 2000 Schrezenmeir and de Vrese, 2001 Shin et al, 2000 Gmeiner et al, 2000) point to a synergistic effect of probiotic and prebiotic combinations on the faecal microbiota of experimental animals. This effect was demonstrated by increased total anaerobes, aerobes, lactobacilli and bifidobacteria counts as well as by decreased Clostridia, Enterobacteriaceae and E. coli counts. The combination of probiotics and non-digestible carbohydrates may be a way of stabilisation and/or improvement of the probiotic effect. 

Myeloma proteins occur in animal tumors of various types. The synthesis of these proteins can be induced in some experimental animals by injection of mineral oil, or the implantation of plastic discs.161 Myeloma proteins were shown to possess antibody activity, with specificity for different types of substances.161 Some of these proteins were found to combine with such carbohydrates as bacterial, cell-wall polysaccharides, lipopolysaccharides, dextrans, levans, and galactans.162 Myeloma proteins that combine with galactans or dextrans possess anti-galactan activity,163,164 or anti-dextran activity,165-167 and have been studied most extensively. 

For the configuration-conformational properties of simple carbohydrates, as well as their reactivities, comprehensive treatises should be consulted (Pigman and Horton, 1972). It has to be mentioned on closing, that recent achievements in macromolecular science have established the ways to the synthesis of linear homopolysaccharides and copolysaccharides (normally by cationic polymerization) of different suitably protected anhydrosugars (Schuerch, 1981). These syntheses open the route to the availability for our studies of a variety of tailor made carbohydrate polymers. A few synthetic polysaccharides have in fact already been used to investigate immunological and allergic reactions in experimental animals and the interaction of plant lectins with carbohydrates (Schuerch, 1981). 

In this paper, we first present the preparation and characterization of osmium-carbohydrate polymers. This discussion is followed by a review of our studies involving animals. Mice have been used for toxicity screening, and we have examined the effect of osmarins upon the tissues of the synovial space in both pigs and rabbits. Finally, we report the results of a small number of experimental treatments of arthritic dogs. 

All aspects of the biochemical role of biotin have not yet been clarified. The vitamin has been implicated in the metabolism of carbohydrates, lipids, proteins, and nucleic acids. Available evidence indicates that biotin acts as a CO2 carrier in a number of carboxyla-tion and decarboxylation reactions connected with carbohydrate and fatty acid metabolism. A number of experimental procedures are used to establish the participation of biotin in a given biochemical reaction (1) the study of enzyme activity in biotin-deficient animals (2) the effect of avidin administered in vivo or added to the incubation mixture on the activity of the enzyme under study and (3) purification of the enzyme and demonstration of the existence of enzyme-bound biotin. Studies of this kind have established that biotin is required for the carboxylases of jS-methyl-crotonyl CoA, acetyl-CoA, propionyl CoA, and oxaloacetic transcarboxylase. Only some of the results are presented here [74-76]. 

---