Inhibition of iron-catalyzed oxidations by attainable uric acid and ascorbic acid levels: therapeutic implications for Alzheimer's disease and late cognitive impairment.

Background: Alzheimer's disease (AD) has become one of the major health problems of the developed world. Previous studies have shown that oxidant-induced changes occur in cerebral tissue in AD and in late-onset amnestic mild cognitive impairment. The oxidative damage begins early and involves free radical-mediated effects that cause lipid peroxidations and oxidative protein and nucleic acid damages which begin before the cardinal neuropathologic manifestations.

Simplified method to assay total plasma peroxidase activity and ferriheme products in sickle cell anemia, with initial results in assessing clinical severity in a trial with citrulline therapy.

A method using dianisidine is described to measure promptly the total plasma peroxidase (POX) activity of methemoglobin and other ferrihemes. Methemoglobin (35 mg/dL) is used as POX standard. Three-minute POX activities and total POX concentrations measured by a classic benzidine method were compared in a three-patient trial with citrulline supplementation.