Treatment with ascorbic acid and alpha-tocopherol modulates oxidative-stress markers in the spinal cord of rats with neuropathic pain

Vitamin E (vit. E) and vitamin C (vit. C) are antioxidants that inhibit nociception. The effect of these vitamins on oxidative-stress markers in the spinal cord of rats with chronic constriction injury (CCI) of the sciatic nerve is unknown. This study investigated the effect of intraperitoneal administration of vit. E (15 mg·kg-1·day-1) and vit. C (30 mg·kg-1·day-1), given alone or in combination, on spinal cord oxidative-stress markers in CCI rats. Adult male Wistar rats weighing 200-250 g were divided equally 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), which received injections of vitamins or vehicle (saline containing 1% Tween 80) for 3 or 10 days (n=6/each group). The vitamins prevented the reduction in total thiol content and the increase in superoxide-anion generation that were found in vehicle-treated CCI rats. While nitric-oxide metabolites increased in vehicle-treated CCI rats 3 days after surgery, these metabolites did not show significant changes in vitamin-treated CCI rats. In all rats, total antioxidant capacity and hydrogen-peroxide levels did not change significantly. Lipid hydroperoxides increased 25% only in vehicle-treated CCI rats. These changes may contribute to vit. C- and vit. E-induced antinociception, because scavenging reactive oxygen species seems to help normalize the spinal cord oxidative status altered by pain.

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

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.

Anti-inflammatory and antioxidant functions of high-density lipoprotein subclasses in patients with acute coronary syndrome / 解放军医学杂志

Objective To assess the anti-inflammatory and antioxidant functions of high-density lipoprotein (HDL) subclasses (HDL2 and HDL3) in patients with acute coronary syndrome (ACS), and to elucidate whether incapacitation of HDL subclasses occurred in ACS patients. Methods Forty ACS patients hospitalized in Nanfang Hospital from Jan. 2011 to Jan. 2012 (ACS group), and 40 subjects simultaneously receiving health examination (control group) were enrolled in present study. Plasma lipid and hypersensitive C reactive protein (hs-CRP) levels, HDL subclasses inflammatory index (HII), paraoxonase-1 (PON1) activity and lipid hydroperoxide (LOOH) levels in both groups were measured. Results The low-density lipoprotein cholesterol (LDL-C) and hs-CRP levels were higher in ACS group than in control group (P0.05). Conclusions The incapacitation of HDL subclasses may occur in ACS patients, with an attenuated antioxidant ability and accentuated proinflammatory function. Mature HDL2 possesses better anti-inflammatory and antioxidant function than HDL3, thus playing a better cardioprotective effect.

Superoxide dismutase and lipid hydroperoxides in blood and endometrial tissue of patients with benign, hyperplastic and malignant endometrium

Epidemiological and experimental data point to involvement of oxygen derived radicals in the pathogenesis of gynecological disorders, as well as in cancer development. The objective of the present study was to examine changes in activities and levels of copper/zinc superoxide dismutase (CuZnSOD) and lipid hydroperoxides (LOOH) in blood and endometrial tissue of patients diagnosed with uterine myoma, endometrial polypus, hyperplasia simplex, hyperplasia complex and adenocarcinoma endometrii. The results of our study have shown decreased SOD activities and unchanged SOD protein level in blood of all examined patients in comparison to healthy subjects. Decrease of both SOD activity and level was found in endometrium of patients with hyperplasia simplex, hyperplasia complex and adenocarcinoma in comparison to women with polypus or myoma. LOOH level was elevated in both tissues of patients with hyperplasiaor adenocarcinoma in comparison to healthy subjects or patients with benign diagnosis. Our findings suggest that the decrease in SOD activity and level, as well as the increase in LOOH level, in patients with gynecological disorders, render these patients more susceptible to oxidative damage caused by reactive oxygen species (ROS). An imbalance in ROS formation and SOD level may be important in the pathogenesis and/or perpetuation of tissue damage in gynecological patients. Since evidence suggests that SOD may be a therapy target for cancer treatment, our findings provide a basis for further research and options for clinical applications.

Resultados epidemiológicos e experimentais apontam para o envolvimento dos radicais derivados do oxigênio na patogênese das moléstias ginecológicas, assim como no desenvolvimento do câncer. O objetivo do presente estudo foi o de examinar as alterações nas atividades e níveis de Cu/Zn superóxido dismutase (CuZnSOD) e hidroperóxidos lipídicos (LOOH)no sangue e tecido endometrial de pacientes diagnosticados com mioma uterino, pólipo endometrial, hiperplasia simplex, hiperplasia complex e adenocarcinoma do endométrio. Os resultados de nosso estudo mostraram atividades de SOD diminuídas e nível de SOD proteína inalterado no sangue de todos os pacientes examinados em comparação a indivíduos saudáveis. Diminuição de ambos, atividade de SOD e nível protéico, foram encontrados no endométrio de pacientes com hiperplasia simplex, hiperplasia complex e adenocarcinoma em comparação às mulheres com pólipos e/ou mioma. O nível de LOOH estava elevado em ambos os tecidos de pacientes com hyperplasia e adenocarcinoma em comparação a indivíduos saudáveis ou pacientes com diagnóstico benigno. Nossos resultados sugerem que um decréscimo na atividade e nível protéico de SOD, assim como um incremento no nível de LOOH, em pacientes com desordens ginecológicas, tornam esses pacientes mais susceptíveis ao dano oxidativo causado pelas espécies reativas de oxigênio (ROS). Um desequilíbrio na formação de ROS e no nível de SOD pode ser importante na patogênese e/ou perpetuação do dano tecidual em pacientes ginecológicos. Desde que existe evidência de que SOD pode ser um alvo para terapia de câncer, nossos resultados fornecem uma base para futura pesquisa e opções para aplicações clínicas.