Limits...
Soyasaponin I improved neuroprotection and regeneration in memory deficient model rats.

Hong SW, Heo H, Yang JH, Han M, Kim DH, Kwon YK - PLoS ONE (2013)

Bottom Line: Oral administration of soya-I exhibited significant memory-enhancing effects in the passive avoidance, Y-maze, and Morris water maze tests.Addition of soya-Ι in the cultured NPCs significantly elevated the markers for cell proliferation (Ki-67) and neuronal differentiation (NeuN, TUJ1, and MAP2).Soya-Ι may improve hippocampal learning and memory impairment by promoting proliferation and differentiation of NPCs in the hippocampus through facilitation of neuronal regeneration and minimization of neuro-inflammation.

View Article: PubMed Central - PubMed

Affiliation: Department of Life and Nanopharmaceutical Sciences, Kyung Hee University, Hoegi-dong, Dongdaemoon-gu, Seoul, Republic of Korea.

ABSTRACT
Soy (Glycine Max Merr, family Leguminosae) has been reported to possess anti-cancer, anti-lipidemic, estrogen-like, and memory-enhancing effects. We investigated the memory-enhancing effects and the underlying mechanisms of soyasaponin I (soya-I), a major constituent of soy. Impaired learning and memory were induced by injecting ibotenic acid into the entorhinal cortex of adult rat brains. The effects of soya-I were evaluated by measuring behavioral tasks and neuronal regeneration of memory-deficient rats. Oral administration of soya-I exhibited significant memory-enhancing effects in the passive avoidance, Y-maze, and Morris water maze tests. Soya-Ι also increased BrdU incorporation into the dentate gyrus and the number of cell types (GAD67, ChAT, and VGluT1) in the hippocampal region of memory-deficient rats, whereas the number of reactive microglia (OX42) decreased. The mechanism underlying memory improvement was assessed by detecting the differentiation and proliferation of neural precursor cells (NPCs) prepared from the embryonic hippocampus (E16) of timed-pregnant Sprague-Dawley rats using immunocytochemical staining and immunoblotting analysis. Addition of soya-Ι in the cultured NPCs significantly elevated the markers for cell proliferation (Ki-67) and neuronal differentiation (NeuN, TUJ1, and MAP2). Finally, soya-I increased neurite lengthening and the number of neurites during the differentiation of NPCs. Soya-Ι may improve hippocampal learning and memory impairment by promoting proliferation and differentiation of NPCs in the hippocampus through facilitation of neuronal regeneration and minimization of neuro-inflammation.

Show MeSH

Related in: MedlinePlus

Neuronal cell types and microglia activation affected by soya-Ι administration in memory-deficient rats.A. Confocal laser scanning microscopic images of GAD67, VGluT1, ChAT, OX42-positive cells in the hippocampal region of brain slices (green: marker-positive cells, red: propidium iodide (PI)). B. The numbers of GAD67-positive cells in the hippocampal region of rat brain slices (soya-I-treated and IBO-injected control) compared with the saline-injected sham group. C. The numbers of VGluT1-positive cells in a microscopic field of the CA1 region in the hippocampal region of IBO-injected rat brain slice compared with the sham group. D. The numbers of ChAT-positive cells in the hippocampal region of IBO-injected rat brain slices, compared with the sham group. E. The average intensities of OX42-positive cells in a microscopic field of the CA1 and DG were normalized according to the sham group. The numbers of PI-positive cells were between 80 and 110 cells in a microscopic field. Immunohistochemical analyses were conducted as described in Materials and Methods (intensity of OX42 staining was analyzed using the ImageJ software: http://rsb.info.nih.gov/ij/). Five different animals were used for each treatment group. Data represent means ± SEM (#p < 0.05, ##p < 0.01, ###p < 0.001, compared with the sham group, *p < 0.05, **p < 0.01, ***p < 0.001 compared with the IBO group by the Newman-Keuls Multiple Comparison Test).
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3852400&req=5

pone-0081556-g003: Neuronal cell types and microglia activation affected by soya-Ι administration in memory-deficient rats.A. Confocal laser scanning microscopic images of GAD67, VGluT1, ChAT, OX42-positive cells in the hippocampal region of brain slices (green: marker-positive cells, red: propidium iodide (PI)). B. The numbers of GAD67-positive cells in the hippocampal region of rat brain slices (soya-I-treated and IBO-injected control) compared with the saline-injected sham group. C. The numbers of VGluT1-positive cells in a microscopic field of the CA1 region in the hippocampal region of IBO-injected rat brain slice compared with the sham group. D. The numbers of ChAT-positive cells in the hippocampal region of IBO-injected rat brain slices, compared with the sham group. E. The average intensities of OX42-positive cells in a microscopic field of the CA1 and DG were normalized according to the sham group. The numbers of PI-positive cells were between 80 and 110 cells in a microscopic field. Immunohistochemical analyses were conducted as described in Materials and Methods (intensity of OX42 staining was analyzed using the ImageJ software: http://rsb.info.nih.gov/ij/). Five different animals were used for each treatment group. Data represent means ± SEM (#p < 0.05, ##p < 0.01, ###p < 0.001, compared with the sham group, *p < 0.05, **p < 0.01, ***p < 0.001 compared with the IBO group by the Newman-Keuls Multiple Comparison Test).

Mentions: Based on the animal behavior test results, we investigated how soya-Ι facilitates the learning and memory abilities of memory deficient model rats. To examine whether soya-I could facilitate the proliferation and differentiation of hippocampal cells, which are responsible for the formation of learning and memory, we performed immunohistochemical staining of rat brain tissues using markers for cell proliferation (BrdU) (Figure 2) and neuronal subtypes (ChAT, vGluT1, and GAD67) (Figure 3). Immunostaining was visualized using secondary antibodies conjugated with fluorescence dye and scanned using a confocal laser scanning microscope. The number of endogenous BrdU-positive cells in the hippocampal region was increased by oral administration of soya-Ι (Figure 2A), compared with the IBO group. In particular, the number of BrdU-positive cells in the DG showed a significant increase with all doses (5, 10, and 20 mg·kg-1 groups) of orally administered soya-Ι. Soya-I at 10 mg·kg-1 resulted in the largest increase in the number of BrdU-positive cells (Sham n = 4, IBO n = 3, Soya-I 5 mg·kg-1 n = 3, Soya-I 10 mg·kg-1 n = 3, Soya-I 20 mg·kg-1 n = 3; F4,11 = 18.18, p < 0.0001 by One-way ANOVA; Figure 2B).


Soyasaponin I improved neuroprotection and regeneration in memory deficient model rats.

Hong SW, Heo H, Yang JH, Han M, Kim DH, Kwon YK - PLoS ONE (2013)

Neuronal cell types and microglia activation affected by soya-Ι administration in memory-deficient rats.A. Confocal laser scanning microscopic images of GAD67, VGluT1, ChAT, OX42-positive cells in the hippocampal region of brain slices (green: marker-positive cells, red: propidium iodide (PI)). B. The numbers of GAD67-positive cells in the hippocampal region of rat brain slices (soya-I-treated and IBO-injected control) compared with the saline-injected sham group. C. The numbers of VGluT1-positive cells in a microscopic field of the CA1 region in the hippocampal region of IBO-injected rat brain slice compared with the sham group. D. The numbers of ChAT-positive cells in the hippocampal region of IBO-injected rat brain slices, compared with the sham group. E. The average intensities of OX42-positive cells in a microscopic field of the CA1 and DG were normalized according to the sham group. The numbers of PI-positive cells were between 80 and 110 cells in a microscopic field. Immunohistochemical analyses were conducted as described in Materials and Methods (intensity of OX42 staining was analyzed using the ImageJ software: http://rsb.info.nih.gov/ij/). Five different animals were used for each treatment group. Data represent means ± SEM (#p < 0.05, ##p < 0.01, ###p < 0.001, compared with the sham group, *p < 0.05, **p < 0.01, ***p < 0.001 compared with the IBO group by the Newman-Keuls Multiple Comparison Test).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3852400&req=5

pone-0081556-g003: Neuronal cell types and microglia activation affected by soya-Ι administration in memory-deficient rats.A. Confocal laser scanning microscopic images of GAD67, VGluT1, ChAT, OX42-positive cells in the hippocampal region of brain slices (green: marker-positive cells, red: propidium iodide (PI)). B. The numbers of GAD67-positive cells in the hippocampal region of rat brain slices (soya-I-treated and IBO-injected control) compared with the saline-injected sham group. C. The numbers of VGluT1-positive cells in a microscopic field of the CA1 region in the hippocampal region of IBO-injected rat brain slice compared with the sham group. D. The numbers of ChAT-positive cells in the hippocampal region of IBO-injected rat brain slices, compared with the sham group. E. The average intensities of OX42-positive cells in a microscopic field of the CA1 and DG were normalized according to the sham group. The numbers of PI-positive cells were between 80 and 110 cells in a microscopic field. Immunohistochemical analyses were conducted as described in Materials and Methods (intensity of OX42 staining was analyzed using the ImageJ software: http://rsb.info.nih.gov/ij/). Five different animals were used for each treatment group. Data represent means ± SEM (#p < 0.05, ##p < 0.01, ###p < 0.001, compared with the sham group, *p < 0.05, **p < 0.01, ***p < 0.001 compared with the IBO group by the Newman-Keuls Multiple Comparison Test).
Mentions: Based on the animal behavior test results, we investigated how soya-Ι facilitates the learning and memory abilities of memory deficient model rats. To examine whether soya-I could facilitate the proliferation and differentiation of hippocampal cells, which are responsible for the formation of learning and memory, we performed immunohistochemical staining of rat brain tissues using markers for cell proliferation (BrdU) (Figure 2) and neuronal subtypes (ChAT, vGluT1, and GAD67) (Figure 3). Immunostaining was visualized using secondary antibodies conjugated with fluorescence dye and scanned using a confocal laser scanning microscope. The number of endogenous BrdU-positive cells in the hippocampal region was increased by oral administration of soya-Ι (Figure 2A), compared with the IBO group. In particular, the number of BrdU-positive cells in the DG showed a significant increase with all doses (5, 10, and 20 mg·kg-1 groups) of orally administered soya-Ι. Soya-I at 10 mg·kg-1 resulted in the largest increase in the number of BrdU-positive cells (Sham n = 4, IBO n = 3, Soya-I 5 mg·kg-1 n = 3, Soya-I 10 mg·kg-1 n = 3, Soya-I 20 mg·kg-1 n = 3; F4,11 = 18.18, p < 0.0001 by One-way ANOVA; Figure 2B).

Bottom Line: Oral administration of soya-I exhibited significant memory-enhancing effects in the passive avoidance, Y-maze, and Morris water maze tests.Addition of soya-Ι in the cultured NPCs significantly elevated the markers for cell proliferation (Ki-67) and neuronal differentiation (NeuN, TUJ1, and MAP2).Soya-Ι may improve hippocampal learning and memory impairment by promoting proliferation and differentiation of NPCs in the hippocampus through facilitation of neuronal regeneration and minimization of neuro-inflammation.

View Article: PubMed Central - PubMed

Affiliation: Department of Life and Nanopharmaceutical Sciences, Kyung Hee University, Hoegi-dong, Dongdaemoon-gu, Seoul, Republic of Korea.

ABSTRACT
Soy (Glycine Max Merr, family Leguminosae) has been reported to possess anti-cancer, anti-lipidemic, estrogen-like, and memory-enhancing effects. We investigated the memory-enhancing effects and the underlying mechanisms of soyasaponin I (soya-I), a major constituent of soy. Impaired learning and memory were induced by injecting ibotenic acid into the entorhinal cortex of adult rat brains. The effects of soya-I were evaluated by measuring behavioral tasks and neuronal regeneration of memory-deficient rats. Oral administration of soya-I exhibited significant memory-enhancing effects in the passive avoidance, Y-maze, and Morris water maze tests. Soya-Ι also increased BrdU incorporation into the dentate gyrus and the number of cell types (GAD67, ChAT, and VGluT1) in the hippocampal region of memory-deficient rats, whereas the number of reactive microglia (OX42) decreased. The mechanism underlying memory improvement was assessed by detecting the differentiation and proliferation of neural precursor cells (NPCs) prepared from the embryonic hippocampus (E16) of timed-pregnant Sprague-Dawley rats using immunocytochemical staining and immunoblotting analysis. Addition of soya-Ι in the cultured NPCs significantly elevated the markers for cell proliferation (Ki-67) and neuronal differentiation (NeuN, TUJ1, and MAP2). Finally, soya-I increased neurite lengthening and the number of neurites during the differentiation of NPCs. Soya-Ι may improve hippocampal learning and memory impairment by promoting proliferation and differentiation of NPCs in the hippocampus through facilitation of neuronal regeneration and minimization of neuro-inflammation.

Show MeSH
Related in: MedlinePlus