Meloxicam-loaded nanocapsules as an alternative to improve memory decline in an Alzheimer’s disease model in mice: involvement of Na<Superscript>+</Superscript>, K<Superscript>+</Superscript>-ATPase

The objective of this study was to investigate the effect of meloxicam-loaded nanocapsules (M-NC) on the treatment of the memory impairment induced by amyloid β-peptide (aβ) in mice. The involvement of Na⁺, K⁺-ATPase and cyclooxygenase-2 (COX-2) activities in the hippocampus and cerebral cortex was also evaluated. Mice received aβ (3 nmol/ 3 μl/ per site, intracerebroventricular) or vehicle (3 μl/ per site, i.c.v.). The next day, the animals were treated with blank nanocapsules (17 mL/kg) or M-NC (5 mg/kg) or free meloxicam (M-F) (5 mg/kg). Treatments were performed every other day, until the twelfth day. Animals were submitted to the behavioral tasks (open-field, object recognition, Y-maze and step-down inhibitory avoidance tasks) from the twelfth day. Na⁺, K⁺-ATPase and COX-2 activities were performed in hippocampus and cerebral cortex. aβ caused a memory deficit, an inhibition of the hippocampal Na⁺, K⁺-ATPase activity and an increase in the hippocampal COX-2 activity. M-NC were effective against all behavioral and biochemical alterations, while M-F restored only the COX-2 activity. In conclusion, M-NC were able to reverse the memory impairment induced by aβ, and Na⁺, K⁺-ATPase is involved in the effect of M-NC.     

Combining different assays and chemical analysis to characterize the genotoxicity of waters impacted by textile discharges

Waters receiving textile discharges can exhibit genotoxic and mutagenic activity, which has been related to the presence of dyes and aromatic amines as synthesis precursors or byproducts. The aim of this study was to identify dyes and aromatic amines in water samples impacted by textile discharges, and to evaluate the genotoxic responses of these samples using the Salmonella/microsome assay in strains TA98 and YG1041, and the Fpg‐modified comet assay in the RTL‐W1 fish cell line. The genotoxicity of river samples downstream of the discharge was greater than the upstream samples in both of the Ames tests. The Fpg‐modified comet assay detected similar levels of DNA damage in the upstream and downstream samples. Mutagenicity was not detected with TA98, except for the Quilombo River samples, but when YG1041 was used as the tester strain mutagenicity was detected for all sites with a very different profile in upstream sites relative to the other sites. The mutagenic response strongly indicated that aromatic amines or dyes were contributing to the mutagenic activity downstream. The impact of textile discharges was also confirmed by chemical analysis, because the highest concentrations of azo dyes and aromatic amines were detected in the river downstream. This study shows the value of combining assays measuring complementary endpoints to better characterize the mutagenicity of environmental samples, with the advantage that this approach provides an indication of what classes of compounds are responsible for the effect. Environ. Mol. Mutagen. 57:559–571, 2016. © 2016 Wiley Periodicals, Inc.