Lead poisoning, amino acids

Keratin is a natural single-strand polymer consisting of chains of amino acids, with a high proportion of the two sulfur-containing amino acids cysteine and methionine. Keratin is the polymer of hair and nails. The sulfur atoms account for keratin s ability to bond to arsenic, mercury, and lead. Hair analysis has played an important role in forensic evidence in cases of poisoning, and it has been possible to diagnose the extent to which famous people in history were affected by these toxic elements provided a sample of their hair has been preserved. 

Amnesic shellfish poisoning The main toxin associated with ASP is the tricarboxylic amino acid domoic acid (Figure 2), responsible for a human intoxication characterized by a widespread neurological dysfunction, chronic loss of memory, and motor neuropathy. The potent neurotoxic actions of domoic acid are due to the activation of a subtype (non-NMDA) of glutamate neurotransmitter receptors, and the subsequent depolarization leading to seizures and neuronal death. 

Barltrop D (1965) The relationship between some parameters employed in the diagnosis of lead poisoning in childhood with special reference to the excretion of delta-amino laevul ini c acid. Thesis. University of London... 

Chisolm (1962, 1968) recorded the presence of the full Fanconi Syndrome of toxic proximal tubular injury in young children, i.e., aminoaciduria, gluco-suria, and hyperphosphaturia, while other researchers have described elevated urinary levels of amino acids or glucose. The threshold in PbB associated with early tubular injury in acute childhood lead poisoning leading to Fanconi Syndrome was reported as typically >150 pg/dl, and lower levels of Pb,... 

With the exception of the first effect, the other effects are fairly subtle metabolic disorders that can lead to diseases in humans and animals rather than to poisoning. Toxicologically important amino acids that are part of human food or animal feed are usually divided into several groups. They are mainly identified as ... 

Calcium and iron deficiencies increase the amount of lead that an individual absorbs into his or her body. Animal studies have shown that some dietary substances bind lead and increase its solubility, thus enhancing its absorption. These substances include sodium citrate (a salt of citric acid) ascorbate (a salt of vitamin C) amino acids, vitamin D, protein, fat, and lactose. Recently, it has also been suggested that antioxidants such as vitamins B6, C, and E, beta-carotene, selenium, and/or zinc might help prevent and/or treat lead poisoning. ... 

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