Tributyltin (TBT) induces oxidative stress and modifies lipid profile in the filamentous fungus Cunninghamella elegans

To investigate the response of the tributyltin-degrading fungal strain Cunninghamella elegans to the organotin, a comparative lipidomics strategy was employed using an LC/MS-MS technique. A total of 49 lipid species were identified. Individual phospholipids were then quantified using a multiple reaction monitoring method. Tributyltin (TBT) caused a decline in the amounts of many molecular species of phosphatidylethanolamine or phosphatidylserine and an increase in the levels of phosphatidic acid, phosphatidylinositol and phosphatidylcholine. In the presence of TBT, it was observed that overall unsaturation was lower than in the control. Lipidome data were analyzed using principal component analysis, which confirmed the compositional changes in membrane lipids in response to TBT. Additionally, treatment of fungal biomass with butyltin led to a significant increase in lipid peroxidation. It is suggested that modification of the phospholipids profile and lipids peroxidation may reflect damage to mycelium caused by TBT.     

Heavy metal exposure in large game from a lead mining area: Effects on oxidative stress and fatty acid composition in liver

The Pb mining area of the valley of Alcudia and the Sierra Madrona mountains (S. Spain) has been exploited intermittently for over 2100 years, since Roman occupation and up until the late 1900s. Red deer (n = 168) and wild boar (n = 58) liver and bone (metacarpus) were analyzed for Pb, Zn, Cu, Cd, As and Se. Lipid peroxidation, total and oxidized glutathione (GSH), superoxide dismutase (SOD), GSH peroxidase (GPX) and fatty acid composition were studied in liver of red deer. The concentrations of Pb in liver and bone of red deer and wild boar were higher in the mining area than in the control area, and higher in the wild boar than red deer, but well below the level associated with clinical signs of Pb poisoning. Liver levels of Cu, Cd and Se were also higher in red deer from the mining area. Red deer from the mining area had 39% less total GSH than in the control area. The percentage of docosahexaenoic acid in liver of red deer from the mining area was 16% lower than in the control area.     

Salicylic acid involved in the regulation of nutrient elements uptake and oxidative stress in Vallisneria natans (Lour.) Hara under Pb stress

In this study, the alterations in nutrient elements content, reactive oxygen species level and antioxidant response were studied in leaves of Vallisneria natans (Lour.) Hara exposed to salicylic acid (SA, 10 or 100 μM), or Pb (50 μM) or their combinations for 4 d. No significant alterations in Mn and Ca content were observed but content of Cu, Zn, Fe and P decreased in plants exposed to SA alone. SA application inhibited the uptake of Pb and partially reversed Pb-induced the alterations in Mn, Ca and Fe content in leaves of V. natans exposed to 50 μM Pb. The decreased chlorophyll (a + b) and increased malondialdehyde and O²⁻ and H₂O₂ content were detected in plants exposed to 100 μM SA, 50 μM Pb, 10 μM SA + 50 μM Pb or 100 μM SA + 50 μM Pb. Application SA partially inhibited Pb-induced the increase of malondialdehyde, O²⁻ and H₂O₂ content. 100 μM SA decreased the activity of NADH oxidase and the content of non-protein thiols, carotenoids and ascorbic acid and increased the content of dehydroascorbate in plants treated with or without Pb. SA alone decreased the ascorbate peroxidase activity and increased the catalase and peroxidase activity, while SA application increased catalase activity but had no significant effect on ascorbate peroxidase and peroxidase activity in V. natans exposed to Pb. The results indicate that SA involves in the regulation of Pb uptake, nutrient balance and oxidative stress.     

Nitrogen dioxide induced changes in level of free fatty acids, triglyceride, esterified fatty acid, ganglioside and lipase activity in the guinea pig brain.

The biochemical response to controlled inhalation of nitrogen dioxide (NO2) was studied in 18 male guinea pigs. Animals were exposed to 2.5, 5.0, and 10 ppm NO2 for 2h daily for 35 consecutive days, and the results compared with six control animals exposed to filtered air for 2h daily for same period. Five biochemical parameters, including triglyceride, free fatty acids, esterified fatty acid, ganglioside and lipase activity were measured immediately after the last day of exposure. At 2.5 ppm NO2 inhalation no significant changes occurred in any region of the central nervous system (CNS). While as the dose concentration was increased to 5 and 10 ppm nitrogen dioxide, significant dose-related alteration were observed in the levels of triglyceride, free fatty acid, esterified fatty acid, ganglioside and lipase activity in the different regions of the guinea pig CNS.