Havrylyak V. Biochemical and species peculiarities of the hair structure in health and pathology

Object – the structural and functional organization of keratin fibers in health, pathology and under experimental damage condition.Purpose – to determine the structural and chemical composition of human hair, rat hair and wool fibers in health, pathology and under experimental damage condition.Methods: microscopical, biochemical, biophysical, statistical. Novelty: the comprehensive studies made it possible to detect the structural and chemical changes in keratin fibers in health, pathology and under experimental damage condition. The species features of content and composition of intermediate filament proteins and keratin-associated proteins which are characterized by a different ratio of crystalline and amorphous phases of keratin. For the first time, the amino acid composition, localization and distribution of mineral elements in different structures of wool fibers under pathological thinning and in human hair under diffuse alopecia. For the first time, it has been shown that pathological thinning of wool fibers accompanied by changes of qualitative and quantitative characteristics of structural lipids, in particular decreasing of sulpholipids in it's free and bound fractions and twofold decrease of the total content of 18-metyleycosanoic acid. It was proposed the bioimpedance spectroscopy in the range of frequency alternating electric current from 1 kHz to 70 rHz to detect the changes in the structural organisation of keratin fibers. Results: the results about species and biochemical features of structural and functional organization of hair and their changes in health, pathology and under experimantal damage condition were presented in the thesis.New methodological approaches to evaluate of keratin fibers defects and damages allowed to offer integrated biochemical markers for their testing. It was found that the biochemical markers which characterize diffuse hair loss in humans are hair strength, the matrix protein content, the selenium and sulfur content in protein fractions - keratoses. For the evaluation the degree of pathological thinning of wool fibers the parameters such as cystine and copper content, as well as matrix proteins in wool should be considered. It was proved experimentally the feasibility of boric acid using for carbonization of wool. It has been shown that oxidative stress caused by chemical treatment of the hair depends on its duration and accompanied by significant changes in the structural and functional organization of keratin. The bioimpedance analysis for study the structure of keratin fibers in a wide frequency range was used and the informative parameters of this method was determined.