Nutri-Metabonomics Study On The Different Responses To Nutritional Intervention In Cats

Cats are one of the most popular pets all over the world. Cats exhibit an interesting and unique metabolism as a consequence of their genetic evolution which is characterized historically by their special requirements in dietary nutrition, compared to omnivorous and herbivorous animals. Cats require high dietary protein which is 2-3 times compared to other mammals. The high protein requirement of cats is a consequence of the lack of regulation of aminotransferases of dispensable N metabolism, which leads to cats continually deplete N from body pool. In addition, cats also obligatory require specific amino acids that are not always essential for other animals due to the abnormal activities of some enzymes in cats'metabolism. The dietary requirements for taurine and arginine cause by low activities of two enzymes in the pathways of sythesis these two amino acids. Cats also require niacin which is the result of high activities of enzymes that metabolise precursors of the vitamin to other compounds. Cats can easily get metabolism disease, such as obesity and diabetes. Understanding nutritional conditions of cats not only benefits the development the pet food industry, but also help to explore the meachnism of metabolic diseases in humanMetabonomics or metabolomics is the quantitative measurement of the multiparametric time-related metabolic responses of a complex (multicellular) system to a pathophysiological intervention or genetic modification. Thus metabonomics seeks to assess homeostatic and pathological responses to interventions or stressors at a holistic and systematic level. Metabolome is the result of whole expression of proteome, transcriptome, genome which reflect the biochemical status directly. Urine sampling is non-invasive and commonly used for in vivo metabolic profiling. It is very important for the illustration of the complicated life systems because of the sensitive response of the changes of the philological and pathological status of the life. The main characteristics of metabonomics are the high-throughput experiment and sophisticated mulitivariate statistical techniques. Metabonomics is becoming an important hotspot for the research of disease and health in the world now.In this work, we attempted to use metabonomics approach to discover the different response of cats after fed with different content of dietary protein. Nutritional intervention may trigger systemic biochemical and physiological changes in living organisms, leading to a loss of homeostasis, which can be evaluated by NMR (nuclear magnetic resonance), combined with multivariate statistical methods. In this study, urinary metabolite profiling of female cats fed with different content of dietary protein for 24 months using high resolution NMR combined with multivariate statistical methods revealed drastic biochemical changes as evidenced by fluctuations urinary metabolites. The metabonomics approach enables us to visualize significant changes in metabolite expression patterns as a result of dietary protein induced the metabolic responses of cats. Several major metabolic pathways including urea cycle, the tricarboxylic acid (TCA) cycle, tryptophan, and gut microbiota-related metabolites were identified to be involved in metabolic changing after different dietary protein.A rapid analytical method for qualitativing felinine and isovarylglycine in cat urine by NMR coupled to SPE (solid phase extraction) is described. All analyses were extracted by solid phase extraction optimized to obtain good recovery and heeled to analysis the unknown metabolites in cats urine. 2D NMR (2 dimensional NMR) was optimized for different extraction allow simultaneous analysis of all analytes in a relatively short time.The nutrimetabonomic approach based on NMR profiling of urine samples represents a powerful analytical strategy to assess nutrition of companion animals, providing relevant information on the effects of dietary variations and the degrees of response to dietary modulations.