Title : The neuroprotective properties of rosmarinic acid against cognitive impairments and hippocampal neurogenesis caused by L-methionine in adult rats
Abstract:
L-methionine (L-met) is one of the nine essential amino acids. A high dose of supplementary methionine administration over a long period can promote oxidative stress due to increasing base levels of metabolites, such as homocysteine (Hcy). Homocysteine contributes to neuronal cell damage, which can lead to memory impairment. Rosmarinic acid (RA) is a polyphenolic hydroxycinnamic acid derivative extensively distributed in rosemary, thyme and holy basil. Rosmarinic acid has numerous biological activities, including antioxidants, anti-inflammation and neuroprotection. Therefore, the aim of this study was to investigate the neuroprotective properties of RA on hippocampal neurogenesis and memory impairments caused by L-met in adult rats. Male Spraque-Dawley rats were divided into 6 groups: Control, L-met 1.7 g/kg, RA 10 mg/kg, RA 30 mg/kg, L-met 1.7 g/kg + RA 10mg/kg and L-met 1.7 g/kg + RA 30 mg/kg groups. Animals were treated 1 time a day for 28 days. After drug administration, spatial and recognition memory were investigated using the novel object location (NOL) and the novel object recognition (NOR) tests, respectively. Moreover, BrdU/NeuN p21 was performed to assess neuronal cell survival and cell cycle arrest by immunofluorescence staining technique. The behavioural analysis revealed that the total exploration time were not significantly different among groups in both tests, suggesting that the animals had no significant difference in locomotor activities. Additionally, the animals significantly spent more time exploring the novel location (NOL) and object (NOR) when compare with the old things except for the L-met groups. Animals in L-met groups failed to discriminate location and object using NOL and NOR tests. Furthermore, there were significant increases in the number of cell cycle arrest and decreases neuronal cell survival in L-met group. These results suggest that L-met treatment caused neurogenesis decline and memory impairment. However, co-treatment with RA can attenuate these impairments.
Keywords: Rosmarinic acid, L-methionine, Memory, Neurogenesis
Audience Take Away
- This presentation gives new knowledge for the development and application of rosmarinic acid to improve neurogenesis impairment induced by L-methionine
- This presentation may be used in basic knowledge for research in neurodegenerative diseases and lead to development and adaptation for further study
- Results from this presentation support the effect of rosmarinic acid on memory and hippocampal neurogenesis
