RESUMEN
This study explores the therapeutic benefits of tannic acid (TnA) in an experimental protocol of chronic hypermethioninemia in rats. Rats were categorized into four groups: Group I - control, Group II - TnA 30 mg/kg, Group III - methionine (Met) 0.2-0.4 g/kg + methionine sulfoxide (MS) 0.05-0.1 g/kg, Group IV - TnA/Met + MS. Saline was administered by subcutaneous pathway into groups I and II twice daily from postnatal day 6 (P6) to P28, whereas those in groups III and IV received Met + MS. From P28 to P35, groups II and IV received TnA orally. Animals from group III presented cognitive and memory impairment assessed through object recognition and Y-maze tests (p < 0.05). Elevated levels of reactive species, lipid peroxidation, and nitrites followed by a decline in sulfhydryl content, catalase activity, and superoxide dismutase activity were observed in animals treated with Met + MS (p < 0.05). However, TnA treatment reversed all these effects (p < 0.05). In group III, there was an increase in acetylcholinesterase activity and IL-6 levels, coupled with a reduction in Na+/K+-ATPase activity (p < 0.05). TnA was able to protect against these effects (p < 0.05). The gene expression of catalase, brain-derived neurotrophic factor, and nuclear factor erythroid 2-related factor 2 was decreased in the hippocampus and striatum from group III (p < 0.05). TnA reversed almost all of these alterations (p < 0.05). These findings suggest that TnA is a therapeutic target for patients with hypermethioninemia.
RESUMEN
Neuroinflammation is an event that occurs in several pathologies of brain. Rubus sp. (blackberry) is a powerful antioxidant fruit, and its extract has neuroprotective activity. The aim of this study was to investigate the blackberry extract properties on lipopolysaccharide (LPS)-induced neuroinflammation, in relation to oxidative parameters and acetylcholinesterase activity in the brain structures of mice. We also investigated interleukin-10 levels in serum. Mice were submitted to Rubus sp. extract treatment once daily for 14 days. On the fifteenth day, LPS was injected in a single dose. LPS induced oxidative brain damage and the blackberry extract demonstrated preventive effects in LPS-challenged mice. LPS administration increased reactive oxygen species levels in the cerebral cortex and striatum, as well as lipid peroxidation in the cerebral cortex. However, the blackberry extract prevented all these parameters. Furthermore, LPS decreased thiol content in the striatum and hippocampus, while a neuroprotective effect of blackberry extract treatment was observed in relation to this parameter. The blackberry extract also prevented a decrease in catalase activity in all the brain structures and of superoxide dismutase in the striatum. An increase in acetylcholinesterase activity was detected in the cerebral cortex in the LPS group, but this activity was decreased in the Rubus sp. extract group. Serum IL-10 levels were reduced by LPS, and the extract was not able to prevent this change. Finally, we observed an antioxidant effect of blackberry extract in LPS-challenged mice suggesting that this anthocyanin-rich extract could be considered as a potential nutritional therapeutic agent for preventive damage associated with neuroinflammation.