Study of Proteinuria: Isolation of Proteins from the Nephrotic Syndrome

One of the most puzzling phenomena of abnormal renal physiology is the occurrence of the nephrotic syndrome. The syndrome has been defined by a collection of clinical and pathological symptoms, but there is no correlation between the clinical and pathological symptoms nor is the etiology of the syndrome known. Proteinuria is probably the most distinguishing feature in the nephrotic syndrome, and there are two possible explanations for its occurrence: (1) the excessive amounts of protein found in nephrotic urine could be due to an increased basement membrane permeability in the glomerulus of the kidney or (2) dysproteinemia. An attempt has been made to evaluate the theory of dysproteinemia in connection with the syndrome. The albumin fractions of nephrotic urine have been studied for their amino acid composition by separating them from the urine by paper electrophoresis, hydrolyzing them, and identifying the amino acids present by two-dimensional chromatography. There seem to be no variations in the qualitative makeup of nephrotic albumin from that of normal albumin, but the literature shows that there are some slight variations in the quantitative amino acid composition of nephrotic albumin compared with normal albumin. More extensive and highly developed experimentation along the lines of protein structure and composition must be done before it can conclusively be stated that dysproteinemia is of importance in the nephrotic syndrome.

Involvement of free radicals in peroxidatic reactions catalyzed by chloroperoxidase

The mechanism of chloroperoxidase (CPO)-catalyzed peroxidatic reactions of several substituted hydroquinones was studied at various hydrogen peroxide concentrations. The pathway was studied using cytochrome c as the radical trapping agent. As the hydroquinones became more hindered there was a difference in the amount of radicals trapped. For hydroquinone, 59.3% radical pathway, and methylhydroquinone, 81.4% radical, the difference in radicals trapped is due to a difference in pathway. For 2,3-dimethylhydroquinone (75.4%), trimethylhydroquinone (44.5%), and t-butylhydroquinone (0%) other non-peroxidatic reactions are noticed. Thus, for the more substituted hydroquinones the difference in radicals trapped can not be assigned to a difference in radical pathway. Also, there were problems drawing conclusions for this system due to the catalytic reaction of hydrogen peroxide. The radical trapping ability of 2,4,6-trimethylphenol was investigated for various other substrates. TMP reacted with the radicals generated in the enzymatic reactions of phenol, resorcinol, and m-methoxyphenol. Thus, this TMP system offers further potential as another radical trapping agent for use in these studies.