Limits...
Improved spatial learning and memory by perilla diet is correlated with immunoreactivities to neurofilament and α-synuclein in hilus of dentate gyrus.

Lee J, Park S, Lee JY, Yeo YK, Kim JS, Lim J - Proteome Sci (2012)

Bottom Line: Differential protein expression in the hippocampus was validated by Western blotting using four selected proteins, known to be involved in synaptic plasticity; AMPA receptor, neurofilament, α-synuclein, and β-soluble NSF attachment protein.Brain sections from the perilla-diet groups showed enhanced immunoreactivities to α-synuclein and neurofilament.Especially, neurofilament immunoreactive cells manifested longer neurite projections in the hilus of dentate gyrus of the perilla-diet groups.

View Article: PubMed Central - HTML - PubMed

Affiliation: Major in Food Biomaterials, Kyungpook National University, Daegu, 702-701, South Korea. jkylim@knu.ac.kr.

ABSTRACT

Background: Perilla (Perilla frutescens) oil is very rich in α-linolenic acid, an omega-3 fatty acid. As it is widely reported that omega-3 fatty acid supplementation improves cognitive function in children and adults, feeding rats with perilla diets followed by analysis of proteomic changes in the hippocampus can provide valuable information on the mechanism of learning and memory at the molecular level. To identify proteins playing roles in learning and memory, differentially expressed proteins in the hippocampus of the 5 week old rats fed perilla diets for 3 weeks or 3 months were identified by proteomic analysis and validated by immunological assays.

Results: The perilla diet groups showed improved spatial learning and memory performances in a T-maze test. They also displayed elevated level of 22:6n-3 fatty acid, an omega-3 fatty acid (p<0.05), in the brain compared to the control diet group. Quantitative proteomic analysis using 2-D gels as well as functional annotation grouping with the differentially expressed proteins in the hippocampus showed that those proteins involved in cytoskeleton and transport were the major differentially expressed proteins in the 3-week group, whereas those involved in energy metabolism, neuron projection and apoptosis in addition to cytoskeleton and transport were the major ones in the 3 month group. Differential protein expression in the hippocampus was validated by Western blotting using four selected proteins, known to be involved in synaptic plasticity; AMPA receptor, neurofilament, α-synuclein, and β-soluble NSF attachment protein. Brain sections from the perilla-diet groups showed enhanced immunoreactivities to α-synuclein and neurofilament. Especially, neurofilament immunoreactive cells manifested longer neurite projections in the hilus of dentate gyrus of the perilla-diet groups.

Conclusion: Improved cognitive function upon administration of n-3 fatty acid-rich perilla diet is associated with the differential expression of hippocampal proteins related to cytoskeleton, energy metabolism, transport, neuro-projection, and apoptosis. Particularly, the enhanced immunoreactivities to α-synuclein and neurofilament in the hilus of dentate gyrus suggest that perilla diet supplementation promotes neuronal signaling and alters synaptic plasticity for improved learning and memory.

No MeSH data available.


Related in: MedlinePlus

Performances in a T-maze test. Ten rats in each group fed control diet (black bar), perilla seed diet (white bar), or perilla oil diet (gray bar) for 3 weeks (A) and 3 months (B) were trained until they reach the goal box 6 times consecutively and the numbers of errors they made were counted in each training section. Likewise, after the three training sessions for two weeks, actual tests were given with a reversed goal box at the T-maze (C). The number of trials before reaching the goal box 6 consecutive times were significantly reduced (*, p<0.05) in rats fed perilla or perilla oil diet.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3539918&req=5

Figure 1: Performances in a T-maze test. Ten rats in each group fed control diet (black bar), perilla seed diet (white bar), or perilla oil diet (gray bar) for 3 weeks (A) and 3 months (B) were trained until they reach the goal box 6 times consecutively and the numbers of errors they made were counted in each training section. Likewise, after the three training sessions for two weeks, actual tests were given with a reversed goal box at the T-maze (C). The number of trials before reaching the goal box 6 consecutive times were significantly reduced (*, p<0.05) in rats fed perilla or perilla oil diet.

Mentions: After 3 weeks or 3 months of perilla- or perilla oil-diet intake, 10 rats in each group were tested for learning and memory performance by T-maze tests. Throughout the training period, rats fed a control diet took a longer time to reach the goal box than the perilla-diet groups (Figure 1). Further, reversal of the goal box arm induced larger time difference between the perilla-diet groups and control group (data not shown). The number of trials it took to successfully reach the goal box five consecutive times was significantly altered by reversal of the goal box position. Rats fed with a control diet for 3 weeks took an average of 2.9 ± 0.32 trials, whereas rats fed perilla- or perilla oil-diet showed improved cognitive function (2.3 ± 0.48 or 2.4 ± 0.52 trials, respectively). (Figure 1). When these results were statistically compared with each other in a two-tailed t-test, the perilla-diet and perilla oil-diet groups showed significant differences compared to the control group with p-values of 0.0048 and 0.0192, respectively.


Improved spatial learning and memory by perilla diet is correlated with immunoreactivities to neurofilament and α-synuclein in hilus of dentate gyrus.

Lee J, Park S, Lee JY, Yeo YK, Kim JS, Lim J - Proteome Sci (2012)

Performances in a T-maze test. Ten rats in each group fed control diet (black bar), perilla seed diet (white bar), or perilla oil diet (gray bar) for 3 weeks (A) and 3 months (B) were trained until they reach the goal box 6 times consecutively and the numbers of errors they made were counted in each training section. Likewise, after the three training sessions for two weeks, actual tests were given with a reversed goal box at the T-maze (C). The number of trials before reaching the goal box 6 consecutive times were significantly reduced (*, p<0.05) in rats fed perilla or perilla oil diet.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3539918&req=5

Figure 1: Performances in a T-maze test. Ten rats in each group fed control diet (black bar), perilla seed diet (white bar), or perilla oil diet (gray bar) for 3 weeks (A) and 3 months (B) were trained until they reach the goal box 6 times consecutively and the numbers of errors they made were counted in each training section. Likewise, after the three training sessions for two weeks, actual tests were given with a reversed goal box at the T-maze (C). The number of trials before reaching the goal box 6 consecutive times were significantly reduced (*, p<0.05) in rats fed perilla or perilla oil diet.
Mentions: After 3 weeks or 3 months of perilla- or perilla oil-diet intake, 10 rats in each group were tested for learning and memory performance by T-maze tests. Throughout the training period, rats fed a control diet took a longer time to reach the goal box than the perilla-diet groups (Figure 1). Further, reversal of the goal box arm induced larger time difference between the perilla-diet groups and control group (data not shown). The number of trials it took to successfully reach the goal box five consecutive times was significantly altered by reversal of the goal box position. Rats fed with a control diet for 3 weeks took an average of 2.9 ± 0.32 trials, whereas rats fed perilla- or perilla oil-diet showed improved cognitive function (2.3 ± 0.48 or 2.4 ± 0.52 trials, respectively). (Figure 1). When these results were statistically compared with each other in a two-tailed t-test, the perilla-diet and perilla oil-diet groups showed significant differences compared to the control group with p-values of 0.0048 and 0.0192, respectively.

Bottom Line: Differential protein expression in the hippocampus was validated by Western blotting using four selected proteins, known to be involved in synaptic plasticity; AMPA receptor, neurofilament, α-synuclein, and β-soluble NSF attachment protein.Brain sections from the perilla-diet groups showed enhanced immunoreactivities to α-synuclein and neurofilament.Especially, neurofilament immunoreactive cells manifested longer neurite projections in the hilus of dentate gyrus of the perilla-diet groups.

View Article: PubMed Central - HTML - PubMed

Affiliation: Major in Food Biomaterials, Kyungpook National University, Daegu, 702-701, South Korea. jkylim@knu.ac.kr.

ABSTRACT

Background: Perilla (Perilla frutescens) oil is very rich in α-linolenic acid, an omega-3 fatty acid. As it is widely reported that omega-3 fatty acid supplementation improves cognitive function in children and adults, feeding rats with perilla diets followed by analysis of proteomic changes in the hippocampus can provide valuable information on the mechanism of learning and memory at the molecular level. To identify proteins playing roles in learning and memory, differentially expressed proteins in the hippocampus of the 5 week old rats fed perilla diets for 3 weeks or 3 months were identified by proteomic analysis and validated by immunological assays.

Results: The perilla diet groups showed improved spatial learning and memory performances in a T-maze test. They also displayed elevated level of 22:6n-3 fatty acid, an omega-3 fatty acid (p<0.05), in the brain compared to the control diet group. Quantitative proteomic analysis using 2-D gels as well as functional annotation grouping with the differentially expressed proteins in the hippocampus showed that those proteins involved in cytoskeleton and transport were the major differentially expressed proteins in the 3-week group, whereas those involved in energy metabolism, neuron projection and apoptosis in addition to cytoskeleton and transport were the major ones in the 3 month group. Differential protein expression in the hippocampus was validated by Western blotting using four selected proteins, known to be involved in synaptic plasticity; AMPA receptor, neurofilament, α-synuclein, and β-soluble NSF attachment protein. Brain sections from the perilla-diet groups showed enhanced immunoreactivities to α-synuclein and neurofilament. Especially, neurofilament immunoreactive cells manifested longer neurite projections in the hilus of dentate gyrus of the perilla-diet groups.

Conclusion: Improved cognitive function upon administration of n-3 fatty acid-rich perilla diet is associated with the differential expression of hippocampal proteins related to cytoskeleton, energy metabolism, transport, neuro-projection, and apoptosis. Particularly, the enhanced immunoreactivities to α-synuclein and neurofilament in the hilus of dentate gyrus suggest that perilla diet supplementation promotes neuronal signaling and alters synaptic plasticity for improved learning and memory.

No MeSH data available.


Related in: MedlinePlus