QUANTITATIVE COMPOSITION OF ESSENTIAL L-AMINO ACIDS IN BLENDED THERAPEUTIC DIETARY PRODUCTS FOR PEOPLE WITH PHENYLKETONURIA

Abstract

Phenylketonuria is one of the most common genetic diseases among the European population that manifests by increased blood phenylalanine content. It has been proven that diet therapy by restricting or excluding phenylalanine is vital for this group of population. Until now, Ukraine has not considered the issue of the quantitative composition of essential amino acids required in the therapeutic amino acid dietary products. Therefore, the aim of this study is to determine the quantitative composition of essential L-amino acids in the therapeutic dietary products for people with phenylketonuria.Mutations in the phenylalanine hydroxylase (PAH) gene and impaired metabolism of the tetrahydrobiopterin cofactor (BH4) lead to phenylalanineemia and the development of phenylketonuria of various forms. Control of phenylalanine (Phe) levels in the blood is only possible by keeping the diet therapy, which includes three key elements: restriction of natural proteins, consumption of products containing L-amino acids without Phe and low-protein food. The composition of the food product for special therapeutic purposes (blended amino acid products) for people with phenylketonuria includes substances containing L-amino acids, micro- and macronutrients, vitamins, sometimes carbohydrates, fats and other nutrients. The quantitative and qualitative composition of a special product should contain a significant proportion of essential amino acids as components of the body nitrogen balance and essential for metabolism. According to the literature about the peculiarities of the breakdown and absorption of essential amino acids, and taking into account desirable blood Phe content, the amount of the amino acids in the blend should be at least 100%, and according to European recommendations, even by 40% higher, when compared with the amino acid composition recommended by WHO / FAO / UNU (2007). This amount of essential amino acids improves the blood Phe content in people with phenylketonuria. Thus, the amount of amino acid composition and the required proportion of essential amino acids in the blended amino acid therapeutic products should be well-balanced and comparable to the age-related nutrition needs for people with various forms of phenylketonuria.

Keywords

• phenylketonuria
• phenylalanine
• diet therapy
• essential amino acids.