Cysteine, N-acetyl

Dekant W, Metzler M, Henschler D. 1986a. Identification of S-l,2-dichlorovinyl- N-acetyl-cysteine as a urinary metabolite of trichloroethylene A possible explanation for its nephrocarcinogenicity in male rats. Biochem Pharmacol 35 2455-2458. 

Simon, L.M. and Suttorp, N. (1983). Lung cell oxidant injury decrease in polymorphonuclear leucocyte mediated cytotoxicity by N-acetyl cysteine. Am. Rev. Resp. Dis. 127, 286. 

Chromium compounds interact synergistically or antagonistically with many chemicals. For example, potassium dichromate administered by subcutaneous injection potentiated the effects of mercuric chloride, citrinin, and hexachloro-1,3-butadiene on rat kidneys (USPHS 1993). Chromium effects were lessened by ascorbic acid and Vitamin E, and N-acetyl cysteine was effective in increasing urinary excretion of chromium in rats (USPHS 1993)... 

Dermal toxicity due to JP-8 may also be attributed to increased free radical formation that may be involved in the development of skin sensitization [45], Following dermal exposure to JP-8, increasing levels of oxidative species are observed [46], In vitro studies with rat lung epithelial cells demonstrated that JP-8-induced cell death is inhibited by exogenous glutathione or the thiol-containing antioxidant N-acetyl-cysteine... 

Treatment of paracetamol overdose is based on replenishment of antioxidant thiols to supplement the role of glutathione the most commonly used antidote is N-acetyl cysteine, but is only effective if given within a particular time window after ingestion. 

Thiol conjugation Epoxides Glutathione S-transferases (glutathione or N-acetylcysteine) Glutathione or N-acetyl cysteine thioethers... 

Drugs used to counteract drug overdosage are considered under the appropriate headings, e.g., physostigmine with atropine naloxone with opioids flu-mazenil with benzodiazepines antibody (Fab fragments) with digitalis and N-acetyl-cysteine with acetaminophen intoxication. 

Metabolites of hexachlorobutadiene (glutathione conjugate, cysteine conjugate, and its N-acetyl cysteine conjugate) produced effects at lower doses than the parent compound after intraperitoneal injection and there was differential susceptibility between sexes (Ishmael and Lock 1986). A single intraperitoneal dose of 25 mg/kg of the conjugates caused minimal to moderate necrosis in males and severe necrosis in females. On the other hand, a comparable dose caused no effect in males and females after exposure to the parent compound (Ishmael and Lock 1986). 

An analogous assay using a radiolabeled soft nucleophile would also be required to complement the hard nucleophile radiolabeled cyanide trapping assay. Investigations into radiolabeled glutathione have proved unsuccessful since the material is unstable due to cross-reactions induced by beta radiation. Alternate soft nucleophiles such as cysteine, N-acetyl cysteine and P-mercaptoethanol all have promise as radiolabeled substances for quantitative trapping experiments since they are more stable than GSH and equally nucleophilic, although clearly these would not be substrates for GST. 

N-acetyl-cysteine, a synthetic precursor of cysteine, is commonly used as an antidote to paracetamol-induced liver damage... 

N-acetyl-cysteine suppresses induction of autophagy by bacterial endotoxin lipopolysacchaiide, hydrogen peroxide, and nitric oxide... 

Agarwal, A., Munoz-Najar, U., Klueh, U., Shih, S. C., and Claffey, K. P. (2004). N-Acetyl-cysteine promotes angiostatin production and vascular collapse in an orthotopic model of breast cancer. Am. ]. Pathol. 164,1683-1696. 

A specific inhibitor of the major proteasomal activities is lactacystin, a compound formed by Streptomyces. Lactacystin is converted reversibly, by loss of N-acetyl-cysteine, into a P-lactone known as c/asto-lactacystin. The N-terminal amino group attacks the reactive four-membered ring of the lactone (Eq. 12-22)358/359... 

Vasdev, S., Ford, C.A., Longerich, L., Parai, S., Gadag, V., and Wadhawan, S. 1998b. Aldehyde induced hypertension in rats prevention by N-acetyl cysteine. Artery 23 10-36. 

Palermo MS, Olabuenaga SE, Giordano M, et al. 1986. Immunomodulation exerted by cyclophosphamide is not interfered by N-acetyl cysteine. Int J Immunopharmacol 8 651-655. 

Berk M, Copolov D, Dean O, Lu K, Jeavons S, et al. 2008. N-acetyl cysteine as a glutathione precursor for schizophrenia - a double-blind, randomized, placebo-controlled trial. Biol Psychiatry 64 361-368. 

Lavoie S, Murray MM, Deppen P, Knyazeva MG, Berk M, et al. 2008. Glutathione precursor, N-acetyl-cysteine, improves mismatch negativity in schizophrenia patients. Neuropsychopharmacology 33 2187-2199. 

In a clinical trial, oral administration of N-acetyl-cysteine, a glutathione precursor, improves clinical symptoms and mismatch negativity. 

Lavoie S, et al. 2007. Glutathione Precursor, N-Acetyl-Cysteine, Improves Mismatch Negativity in Schizophrenia Patients. Neuropsychopharmacology 33 2187-2199. 

Recently, it has been shown that oxidant stress can induce the expression and replication of human immunodeficiency virus-1 (HIV-1) in a human T cell line [64], The effect was shown to be mediated by the transcription factor NFk,B, which was potently and rapidly activated by exposure of target cells to H2O2. Moreover, the activation of NFkB by a variety of stimuli including phorbol-12-myristate-13-acetate (PMA), calcium ionophores and tumour necrosis factor alpha (TNFa) was inhibited by the ROI scavenger, N-acetyl cysteine [64]. It was therefore suggested that the formation of ROI was the common mechanism involved in the activation of NFk,B by a variety of agents. 

Several tests can show if you have been exposed to benzene. Some of these tests may be available at your doctor s office. All of these tests are limited in what they can tell you. The test for measuring benzene in your breath must be done shortly after exposure. This test is not very helpful for detecting very low levels of benzene in your body. Benzene can be measured in your blood. However, since benzene disappears rapidly from the blood, measurements may be accurate only for recent exposures. In the body, benzene is converted to products called metabolites. Certain metabolites of benzene, such as phenol, muconic acid, and S-phenyl-N-acetyl cysteine (PhAC) can be measured in the urine. The amount of phenol in urine has been used to check for benzene exposure in workers. The test is useful only when you are exposed to benzene in air at levels of 10 ppm or greater. However, this test must also be done shortly after exposure, and it is not a reliable indicator of how much benzene you have been exposed to, since phenol is present in the urine from other sources (diet, environment). Measurement of muconic acid or PhAC in the urine is a more sensitive and reliable indicator of benzene exposure. The measurement of benzene in blood or of metabolites in urine cannot be used for making predictions about whether you will experience any harmful health effects. Measurement of all parts of the blood and measurement of bone marrow are used to find benzene exposure and its health effects. 

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