Effects of N-acetylcysteine on spinal cord oxidative stress biomarkers in rats with neuropathic pain

• Published in: Brazilian journal of medical and biological research Vol. 50; no. 12; p. e6533
• Main Authors: Horst, A, de Souza, J A, Santos, M C Q, Riffel, A P K, Kolberg, C, Partata, W A
• Format: Journal Article
• Language: English
• Published: Brazil Associacao Brasileira de Divulgacao Cientifica (ABDC) 01-01-2017; Associação Brasileira de Divulgação Científica
• Subjects: Acetylcysteine; Acetylcysteine - pharmacology; Animals; Antinociception; Antioxidants; Ascorbic acid; Ascorbic Acid - analysis; BIOLOGY; Biomarkers - analysis; Chronic constriction injury; Constriction; Free Radical Scavengers - pharmacology; Health aspects; Lipid hydroperoxides; Lipid Peroxides - analysis; Male; MEDICINE, RESEARCH & EXPERIMENTAL; Neuralgia - drug therapy; Neuralgia - metabolism; Oxidative stress; Oxidative Stress - drug effects; Peripheral nervous system diseases; Rats; Rats, Wistar; Reactive Oxygen Species - metabolism; Reproducibility of Results; Sciatic Neuropathy; Spinal cord; Spinal Cord - drug effects; Spinal Cord - metabolism; Time Factors; Total antioxidant capacity; Treatment Outcome; Antinociception; Total antioxidant capacity; Ascorbic acid; Lipid hydroperoxides; Chronic constriction injury
• ISSN: 0100-879X; 1414-431X; 1414-431X
• DOI: 10.1590/1414-431X20176533

N-acetylcysteine (NAC) inhibits nociceptive transmission. This effect has been associated partly with its antioxidant properties. However, the effect of NAC on the levels of lipid hydroperoxides (a pro-oxidant marker), content of ascorbic acid (a key antioxidant molecule of nervous tissue) and total antioxidant capacity (TAC) is unknown. Thus, our study assessed these parameters in the lumbosacral spinal cord of rats with chronic constriction injury (CCI) of the sciatic nerve, one of the most commonly employed animal models of neuropathic pain. Thirty-six male Wistar rats weighing 200-300 g were equally divided into the following groups: Naive (rats did not undergo surgical manipulation); Sham (rats in which all surgical procedures involved in CCI were used except the ligature), and CCI (rats in which four ligatures were tied loosely around the right common sciatic nerve). All rats received intraperitoneal injections of NAC (150 mg·kg-1·day-1) or saline for 1, 3, or 7 days. Rats were killed 1, 3, and 7 days after surgery. NAC treatment prevented the CCI-induced increase in lipid hydroperoxide levels only at day 1, although the amount was higher than that found in naive rats. NAC treatment also prevented the CCI-induced increase in ascorbic acid content, which occurred at days 1, 3, and 7. No significant change was found in TAC with NAC treatment. The changes observed here may be related to the antinociceptive effect of NAC because modulation of oxidative-stress parameters seemed to help normalize the spinal cord oxidative status altered by pain.