Recent epidemiological observations suggest that acetaminophen (paracetamol) may contribute to asthma morbidity. Impaired endogenous antioxidant defences may have a role in the pathogenesis of a number of inflammatory pulmonary diseases, including asthma. We studied the effect of acetaminophen on the intracellular level of reduced glutathione (GSH) with and without inhibitors of cytochrome P450 or prostaglandin H synthetase, and TNF-alpha, IL-6 and IL-8 protein production in human alveolar macrophages and type II pneumocytes in vitro. Following a 20 h incubation with acetaminophen, cytotoxicity was apparent from>or = 5 and>or = 10 mM in macrophages and type II pneumocytes, respectively. A time- and concentration-dependent decrease of intracellular GSH occurred after acetaminophen (0.05-1 mM) exposure (1-4 h) in pulmonary macrophages (up to 53%) and type II pneumocytes (up to 34%). Diethyldithiocarbamic acid, potassium ethyl xanthate, and indomethacin decreased significantly acetaminophen-induced GSH depletion in the two cell types tested, suggesting the involvement of cytochrome P450 (mainly CYP2E1) and/or prostaglandin H synthetase. In macrophages, acetaminophen decreased the secretion of TNF-alpha (at 4 and 24 h, concentration-related) and IL-6 (at 24 h, at 0.1 mM), and did not affect significantly IL-8 production. These in vitro observations demonstrate that clinically relevant concentrations of acetaminophen decreased: (i) intracellular GSH in human pulmonary macrophages and type II pneumocytes and (ii) the secretion of TNF-alpha and possibly IL-6 by human pulmonary macrophages. These findings provide experimental plausibility to the challenging observations that frequent use of APAP may be a risk factor for asthma morbidity.

Aldehyde reductase (AKR1A) plays a role in the biosynthesis of ascorbic acid (AsA), and AKR1A-deficient mice produce about 10-15% of the AsA that is produced by wild-type mice. We found that acetaminophen (AAP) hepatotoxicity was aggravated in AKR1A-deficient mice. The pre-administration of AsA in the drinking water markedly ameliorated the AAP hepatotoxicity in the AKR1A-deficient mice. Treatment of the mice with AAP decreased both glutathione and AsA levels in the liver in the early phase after AAP administration, and an AsA deficiency delayed the recovery of the glutathione content in the healing phase. While in cysteine supply systems; a neutral amino acid transporter ASCT1, a cystine transporter xCT, enzymes for the transsulfuration pathway, and autophagy markers, were all elevated in the liver as the result of the AAP treatment, the AsA deficiency suppressed their induction. Thus, AsA appeared to exert a protective effect against AAP hepatotoxicity by ameliorating the supply of cysteine that is available for glutathione synthesis as a whole. Because some drugs produce reactive oxygen species, resulting in the consumption of glutathione during the metabolic process, the intake of sufficient amounts of AsA would be beneficial for protecting against the hepatic damage caused by such drugs.

The present study was aimed to test the hypothesis that paracetamol (PCM) can precipitate autistic like features when used to counteract vaccine-induced fever using experimental rat pups. The pups were treated with measles mumps rubella (MMR) vaccine, diphtheria tetanus and pertussis (DPT) vaccines and lipopolysaccharide (LPS) with subsequent PCM treatment. The pups were evaluated for postnatal growth (weight gain, eye opening) and behavior alterations (swimming performance, olfactory discrimination, negative geotaxis, nociception, and locomotor activity) by performing battery of neurobehavioral test. Significant correlation was observed between social behavioral domains (nociception, anxiety and motor coordination) and pro-inflammatory load in the pups when treated with MMR/LPS along with PCM. A significant change in pro and anti-inflammatory (IL-4, IL-6, IL-10) markers were observed in rats treated with PCM, MMR, LPS, DPS alone or in combination with MMR, LPS and DPT (5128.6 ± 0.000, 15,488 ± 0.000, 9661.1 ± 157.29, 15,312 ± 249.29, 10,471 ± 0.00, 16,789 ± 273.34and 12,882 ± 0.00). Pups were also scrutinized for the markers of oxidative stress, inflammation and histopathologically. All the treatment groups showed significant alteration in the behavioral changes, oxidative markers (TBARS-in control-4.33 ± 0.02, PCM-9.42 ± 0.18, MMR-5.27 ± 0.15, MMR + PCM-8.57 ± 0.18, LPS-6.84 ± 0.10, LPS + PCM-4.51 ± 0.30, DPT-5.68 ± 0.12, DPT + PCM-7.26 ± 0.18) and inflammatory markers without following any specific treatment. These observation could be accorded to variable phenotypes of autistic spectrum disorders (ASDs).

BACKGROUND:The aim of the present study was to determine the therapeutic effects of medical ozone therapy on acute acetaminophen (APAP)-induced hepatotoxicity which were not clearly demonstrated in prior studies.

METHOD:Twenty-four mice were randomly assigned into three equal groups: Group 1 (control), Group 2 (APAP) and Group 3 (APAP +ozone). Hepatotoxicity was induced by APAP given as a single dose of 300 mg/kg intraperitoneally in Groups 2 and 3. Additionally, Group 3 received 20 mcg/0.5 mL ozone intraperitoneal twice a day for the remaining of the study. Other groups received saline injections. On the fourth day of the study, biochemical variables (AST, ALT, ALP) and liver histopathology wasassessed.

RESULTS:Intraperitoneal administration of a single dose of APAP induced hepatocellular damage that was shown by both liver enzymes and histopathological changes (p < 0.001). AST, ALT, ALP levels were elevated in both groups 2 and 3 and the difference from group 1 was statistically significant (p < 0.01).Mean ALT and AST levels of group 2 were statistically significantly higher versus group 3 (p < 0.01). In histopathological examinations; necrosis and inflammation were more prominent in Group 2 compared to Group 3 (p < 0.01).

CONCLUSION:Ozone showed beneficial effects on APAP hepatotoxicity at a statistically significant level. It is known that ozone has therapeutic effects in various diseases owing to its antioxidant effects. The present study suggests that ozone may be utilized as a routine supplementary therapy in acute APAP hepatotoxicity.

BACKGROUND:Oxidative stress and inflammation are involved in the pathogenesis of paracetamol-induced renal damage. This study examines the relationship between 8-iso-prostaglandin F2α (8-iso-PGF2α) and platelet activation as well as the relative contribution of the pro-inflammatory markers interleukin (IL)-1β and tumor necrosis factor-α (TNF-α) in enhanced 8-iso-PGF2α biosynthesis, as a complementary onset during analgesic nephropathy induced by chronic treatment with paracetamol. The protective effects of vitamin C on the aforementioned settings are also investigated.

METHODS:Analgesic nephropathy was induced in Wistar rats. Renal function markers and the activity of antioxidant enzymes were determined spectrophotometrically. Immunoassays were used to measure the pro-inflammatory markers and the markers of lipid peroxidation and platelet activation.

RESULTS:The chronic treatment with paracetamol led to renal dysfunction, represented by the elevation of plasma urea and creatinine and the decline in the enzymatic antioxidant status, but did not cause a significant increase in TNF-α and IL-1β. The paracetamol-induced lipid peroxidation and enhanced production of 8-iso-PGF2α was not sufficient to cause changes in platelet activation represented by the level of 11-dehydro thromboxane B2.

CONCLUSIONS:Our results suggest that oxidative stress cannot circumvent the need of stimulation by circulatory cytokines in order to induce inflammatory response and changes in platelet activation during analgesic nephropathy. Vitamin C proved to be beneficial in restoring the renal function markers to normal, increasing the renal enzymatic antioxidant potential, inhibiting lipid peroxidation, and lowering cytokine production and 11-dehydro thromboxane B2 excretion. The observed effects of vitamin C offer support for its potential use as protective treatment in cases of chronic paracetamol overdose.