Alcoholic Extract of Ashwagandha Leaves Protects Against Amnesia by Regulation of Arc Function.
Our earlier report on scopolamine-induced amnesia and its improvement by pre-treatment with i-Extract (alcoholic extract of Ashwagandha leaf) suggested that the i-Extract mediated nootropic effect may involve neuronal immediate early gene, Arc. With a hypothesis that the i-Extract induced expression of Arc protein may cause augmentation in Arc function, we examined the effect of i-extract on a major function of Arc protein, i.e. F-actin expansion, using Arc antisense oligodeoxynucleotides (ODN). Stereotaxic infusion of Arc antisense ODN in the CA1 region of hippocampus decreased the level of Arc protein as demonstrated by immunoblotting. However, this decrease was attenuated when treated with i-Extract prior to infusion of Arc antisense ODN. We noted a significant decrease in the polymerization of F-actin during scopolamine-induced amnesia as well as Arc antisense ODN infusion that was restored rather enhanced when pre-treated with i-Extract in both the cases. We also compared the corresponding changes between CA1 (the infusion site) and CA3 (neighbouring site of infusion) regions of hippocampus, and found more pronounced effects in CA1 than in the CA3 region. The extent of F-actin polymerization, as revealed by changes in the dendritic spine architecture through Golgi staining, showed that both scopolamine as well as Arc antisense ODN disrupted the spine density and mushroom-shaped morphology that was again regained if pre-treated with i-Extract. In conclusion, the findings reveal that the Arc helps in polymerization of F-actin and subsequent changes in the morphology of dendritic spines after pre-treatment with i-Extract in scopolamine-induced amnesic mice, suggesting an important role of Arc in scopolamine-induced amnesia and its recovery by i-Extract.
Biochemistry and Molecular Biology Laboratory, Department of Zoology, Banaras Hindu University, Varanasi, 221005, India.|Centre for Neural and Cognitive Sciences, University of Hyderabad, Hyderabad, 500046, India.
Akash
A
Gautam
DBT-AIST International Laboratory for Advanced Biomedicine (DAILAB), National Institute of Advanced Industrial Science and Technology (AIST), Central 4, 1-1-1 Higashi, Tsukuba, Ibaraki, 305-8562, Japan.
Sunil C
SC
Kaul
Biochemistry and Molecular Biology Laboratory, Department of Zoology, Banaras Hindu University, Varanasi, 221005, India. mkt_bhu@yahoo.com.
Mahendra K
MK
Thakur
D000199:Actins / Q000378:metabolism; D000438:Alcohols / Q000737:chemistry*; D000647:Amnesia / Q000188:drug therapy* / Q000378:metabolism*; D000818:Animals; D015153:Blotting, Western; D003598:Cytoskeletal Proteins / Q000378:metabolism*; D049229:Dendritic Spines / Q000187:drug effects / Q000473:pathology; D015536:Down-Regulation / Q000187:drug effects; D005455:Fluorescent Antibody Technique; D006624:Hippocampus / Q000473:pathology; D008297:Male; D051379:Mice; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D018696:Neuroprotective Agents / Q000494:pharmacology / Q000627:therapeutic use*; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use*; D018515:Plant Leaves / Q000737:chemistry*; D058105:Polymerization; D013194:Staining and Labeling; D013238:Stereotaxic Techniques
D000199:Actins; D000438:Alcohols; D003598:Cytoskeletal Proteins; D009419:Nerve Tissue Proteins; D018696:Neuroprotective Agents; D010936:Plant Extracts; C092069:activity regulated cytoskeletal-associated protein; C030693:Ashwagandha
Amnesia; Arc expression; Dendritic spine morphology; F-actin polymerization; Therapy; i-Extract