Withania somnifera against glutamate excitotoxicity and neuronal cell loss in a scopolamine-induced rat model of Alzheimer’s disease

  • Gopalreddygari Visweswari Department of Neurochemistry, National Institute of Mental Health and Neurosciences, Bangalore, Karnataka, India
  • Rita Christopher Department of Neurochemistry, National Institute of Mental Health and Neurosciences, Bangalore, Karnataka, India
  • W. Rajendra Department of Zoology, Sri Venkateswara University, Tirupati, Andhra Pradesh, India
Keywords: Withania somnifera, Scopolamine, Alzheimer’s disease, Glutamate, Excitotoxicity, Neuronal cell loss


Alzheimer’s disease, a chronic and progressive neurodegenerative disorder with no prevention and cure, affecting nearly 50 million people worldwide. Glutamate is the principal excitatory neurotransmitter in the central nervous system involved in 50% of basic brain functions, especially cortical and hippocampal regions, like memory, cognition, and learning. The glutamate-mediated toxicity is termed as excitotoxicity. The present study was aimed to determine whether the methanolic and water extracts of root from the medicinal plant, Withania somnifera, could decrease the glutamate excitotoxicity and its related neuronal cell loss in a scopolamine-induced animal model of Alzheimer's disease. The rats were randomly divided into different groups of 5 in each: normal control - treated orally with saline; AD model - injected intra peritoneally with scopolamine (2 mg/Kg body wt) alone to induce Alzheimer's disease; AD model rats treated orally with the methanolic extract (AD+ME-WS) (300 mg/Kg body wt), water extract (AD+WE-WS) (300 mg/Kg body wt), and donepezil hydrochloride, a standard control (AD+DZ) (5 mg/Kg body wt) for 30 consecutive days. Increased glutamate (Glu) levels and decreased glutamate dehydrogenase (GDH) activity were reversed with Withania somnifera root extracts in both the cerebral cortex and hippocampus regions in scopolamine-induced Alzheimer's disease model rat brain. The histopathological studies of the same treatment also showed protection against neuronal cell loss in both regions. These results support the idea that these extracts could be effective for the reduction of brain damage by preventing glutamate excitotoxicity generated neuronal cell loss in the scopolamine-induced Alzheimer's disease model.

DOI: http://dx.doi.org/10.5281/zenodo.4426779


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1. Buntup D, Chayasadom A, Surarit R, Chutabhakdikul N, Thangnipon W. Effects of amyloid - peptide on glutamine transporter mRNA expression and cell viability in cultured rat cortical cells. Sci Asia. 2009; 35: 156-160.
2. Perl DP. Neuropathology of Alzheimer’s disease. Mt Sinai J Med. 2010; 77: 32-42.
3. Wang R, Reddy PH. Role of glutamate and NMDA receptors in Alzheimer's Disease. J Alzheimers Dis. 2017; 57: 1041-1048.
4. Parihar MS, Hemnani T. Alzheimer's disease pathogenesis and therapeutic interventions. J Clin Neurosci. 2004; 11: 456-467.
5. Kulkarni KS, Kasture SB, Mengi SA. Efficacy study of Prunus amygdalus (almond) nuts in scopolamine-induced amnesia in rats. Indian J Pharmacol. 2010; 42: 168-173.
6. Ali T, Yoon GH, Shah SA, Lee HY, Kim MO. Osmotin attenuates amyloid beta-induced memory impairment, tau phosphorylation and neurodegeneration in the mouse hippocampus. Sci Rep. 2015; 5: 11708.
7. Alzheimer’s Association. Alzheimer’s disease facts and figures. Alzheimers Dement. 2017; 13: 325-373.
8. Mota SI, Ferreira IL, Rego AC. Dysfunctional synapse in Alzheimer's disease - A focus on NMDA receptors. Neuropharmacology. 2014; 76 Pt A: 16-26.
9. Liu J, Chang L, Song Y, Li H, Wu Y. The Role of NMDA receptors in Alzheimer's Disease. Front Neurosci. 2019; 13: 43.
10. Khakpai F, Zarrindast MR, Nasehi M, Haeri-Rohani A, Eidi A. The role of glutamatergic pathway between septum and hippocampus in the memory formation. EXCLI J. 2013; 12: 41-51.
11. Lu YM, Mansuy IM, Kandel ER, Roder J. Calcineurin-mediated LTD of GABAergic inhibition underlies the increased excitability of CA1 neurons associated with LTP. Neuron. 2000; 26: 197-205.
12. Sheng M, Kim MJ. Postsynaptic signaling and plasticity mechanisms. Science. 2002; 298: 776-780.
13. Nakatsu Y, Kotake Y, Takishita T, Ohta S. Long-term exposure to endogenous levels of tributyltin decreases GluR2 expression and increases neuronal vulnerability to glutamate. Toxicol Appl Pharmacol. 2009; 240: 292-298.
14. Matute C. Glutamate and ATP signaling in white matter pathology. J Anat. 2011; 219: 53-64.
15. Hara MR, Snyder SH. Cell signaling and neuronal death. Annu Rev Pharmacol Toxicol. 2007; 47: 117-141.
16. Yi JH, Hazell AS. Excitotoxic mechanisms and the role of astrocytic glutamate transporters in traumatic brain injury. Neurochem Int. 2006; 48: 394-403.
17. Meldrum BS. Glutamate as a neurotransmitter in the brain: review of physiology and pathology. J Nutr. 2000; 130: 1007S-1015S.
18. Mattson MP. In: Stress: physiology, biochemistry, and pathology. Handbook of Stress Series, 2019; 3: 125-134.
19. Butterfield DA, Pocernich CB. The glutamatergic system and Alzheimer's disease: therapeutic implications. CNS Drugs. 2003; 17: 641-652.
20. Cortese BM, Phan KL. The role of glutamate in anxiety and related disorders. CNS Spectr. 2005; 10: 820-830.
21. Benussi A, Alberici A, Buratti E, Ghidoni R, Gardoni F, Luca MD, et al. Toward a glutamate hypothesis of frontotemporal dementia. Front Neurosci. 2019; 13: 304.
22. Swanson CJ, Bures M, Johnson MP, Linden AM, Monn JA, Schoepp DD. Metabotropic glutamate receptors as novel targets for anxiety and stress disorders. Nat Rev Drug Discov. 2005; 4: 131-144.
23. Bechtholt-Gompf AJ, Walther HV, Adams MA, Carlezon WA Jr, Ongür D, Cohen BM. Blockade of astrocytic glutamate uptake in rats induces signs of anhedonia and impaired spatial memory. Neuropsychopharmacology. 2010; 35: 2049-2059.
24. Verma SK, Kumar A. Therapeutic uses of Withania somnifera (Ashwagandha) with a note on withanolides and its pharmacological actions. Asian J Pharm Clin Res. 2011; 4: 1-4.
25. Jayanthi MK, Prathima C, Huralikuppi JC, Suresha RN, Murali Dhar. Anti-depressant effects of Withania somnifera fat (Ashwagandha ghrutha) extract in experimental mice. Int J Pharm Bio Sci. 2012; 3: 33-42.
26. Kulkarni SK, Dhir A. Withania somnifera: an Indian ginseng. Prog Neuropsychopharmacol Biol Psych. 2008; 32: 1093-1105.
27. Kataria H, Wadhwa R, Kaul SC, Kaur G. Withania somnifera water extract as a potential candidate for differentiation based therapy of human neuroblastomas. PLoS One. 2013; 8: 1.
28. Sharma V, Sharma S, Pracheta. Protective effect of Withania somnifera roots extract on hematoserological profiles against lead nitrate-induced toxicity in mice. Indian J Biochem Biophys. 2012; 49: 458-462.
29. Kiki SM, Mansour HH, Anis L. The modulatory role of Ashwagandha root extract on gamma-radiation-induced nephrotoxicity and cardiotoxicity in male Albino rats. Am J Phytomed Clin Ther. 2014; 2: 622-629.
30. Shah N, Singh R, Sarangi U, Saxena N, Chaudhary A, Kaur G, et al. Combinations of Ashwagandha leaf extracts protect brain-derived cells against oxidative stress and induce differentiation. PLoS One. 2015; 19: 10.
31. Alam N, Hossain M, Mottalib MA, Sulaiman SA, Gan SH, Khalil MI. Methanolic extracts of Withania somnifera leaves, fruits and roots possess antioxidant properties and antibacterial activities. BMC Complem Altern Med. 2012; 12: 175.
32. Jeyanthi T, Subramanian P. Protective effect of Withania somnifera root powder on lipid peroxidation and antioxidant status in gentamicin-induced nephrotoxic rats. J Basic Clin Physiol Pharmacol. 2010; 21: 61-78.
33. Tolar M, Abushakra S, Sabbagh M. The path forward in Alzheimer’s disease therapeutics: Reevaluating the amyloid cascade hypothesis. Alzheimer’s Dement. 2019; 16(1): 1553-1560.
34. Jayaprakasam B, Padmanabhan K, Nair MG. Withanamides in Withania somnifera fruit protect PC-12 cells from beta-amyloid responsible for Alzheimer’s disease. Phytother Res. 2010; 24: 859-863.
35. Beutler HO, Michal G. In: Methods of enzymatic analysis. Bergmeyer HU, ed., 2nd edn., Verlag Chemie, Weinheim/Academic Press, Inc. New York and London, 1974: 1708-1713.
36. Lee YL, Lardy AA. Influence of thyroid hormones on L-glycerophosphate dehydrogenases in various organs of the rat. J Bio Chem. 1965; 240: 1427-1430.
37. Pramilamma Y, Swami KS. Glutamate dehydrogenase activity in the normal and denervated gastrocnemius muscles of frog. Curr Sci. 1975; 44: 739.
38. Yu ZF, Cheng GJ, Hu BR. Mechanism of colchicine impairment of learning and memory, and protective effect of CGP36742 in mice. Brain Res. 1997; 750: 53-58.
39. Akina S, Thati M, Puchchakayala G. Neuroprotective effect of ceftriaxone and selegiline on scopolamine induced cognitive impairment in mice. Adv Biol Res. 2013; 7: 266-275.
40. Rossi DJ, Slater NT. The developmental onset of NMDA receptor-channel activity during neuronal migration. Neuropharmacology. 1993; 32: 1239-1248.
41. Riedel G, Platt B, Micheau J. Glutamate receptor function in learning and memory. Behav Brain Res. 2003; 140: 1-47.
42. Campos-Peña V, Meraz-Ríos MA. Alzheimer’s disease: the role of AB in the glutamatergic system. http://dx.doi.org/10.5772/57367.
43. Butterfield DA, Perluigi M, Sultana R. Oxidative stress in Alzheimer's disease brain: new insights from redox proteomics. Eur J Pharmacol. 2006; 545: 39-50.
44. Farooqui T, Farooqui AA. Curcumin: historical background, chemistry, pharmacological action, and potential therapeutic value. In: Curcumin for neurological and psychiatric disorders. Academic Press, 2019: 23-44.
45. Bajo R, Pusil S, López ME, Canuet L, Pereda E, Osipova D, et al. Scopolamine effects on functional brain connectivity: a pharmacological model of Alzheimer’s disease. Sci Rep. 5. 2015; 9748.
46. Liu W, Rabinovich A, Nash Y, Frenkel D, Wang Y, Youdim MB, Weinreb O. Anti-inflammatory and protective effects of MT-031, a novel multitarget MAO-A and AChE/BuChE inhibitor in scopolamine mouse model and inflammatory cells. Neuropharmacology. 2017; 113: 445-456.
47. Bhuvanendran S, Kumari Y, Othman I, Shaikh MF. Amelioration of cognitive deficit by embelin in a scopolamine-induced Alzheimer’s disease-like condition in a rat model. Front Pharmacol. 2018; 9: 665.
48. Rawls SM, Mcginty JF. Muscarinic receptors regulate extracellular glutamate levels in the rat striatum: an in vivo microdialysis study. J Pharmacol Exp Ther. 1998; 286: 91-98.
49. Kilian JG, Hsu HW, Mata K, Wolf FW, Kitazawa M. Astrocyte transport of glutamate and neuronal activity reciprocally modulate tau pathology in Drosophila. Neuroscience. 2017; 348: 191-200.
50. Yang Q, She H, Gearing M, Colla E, Lee M, Shacka JJ, et al. Regulation of neuronal survival factor MEF2D by chaperone-mediated autophagy. Science. 2009; 323: 124-127.
51. Albin RL, Greenamyre JT. Alternative excitotoxic hypotheses. Neurology. 1992; 42: 733-738.
52. Li Z, Yamamoto Y, Morimoto T, Ono J, Okada S, Yamatodani A. The effect of pentylenetetrazole-kindling on the extracellular glutamate and taurine levels in the frontal cortex of rats. Neurosci Lett. 2000; 282: 117-119.
53. Kim AY, Baik EJ. Glutamate dehydrogenase as a neuroprotective target against neurodegeneration. Neurochem Res. 2019; 44L 147-153.
54. Shen H, Kihara T, Hongo H, Wu X, Kem WR, Shimohama S et al. Neuroprotection by donepezil against glutamate excitotoxicity involves stimulation of α7 nicotinic receptors and internalization of NMDA receptors. Br J Pharmacol. 2010; 161: 127-139.
55. Kataria, H., Wadhwa R, Kaul SC, Kaur G. Water extract from the leaves of Withania somnifera protect RA differentiated C6 and IMR-32 cells against glutamate-induced excitotoxicity. PLoS One. 2012; 7: E37080.
56. Dar NJ, Satti NK, Dutt P, Hamid A, Ahmad M. Attenuation of glutamate-induced excitotoxicity by withanolide-A in neuron-like cells: role for PI3K/Akt/MAPK signaling pathway. Mol Neurobiol. 2018; 55: 2725-2739.
57. Kumar S, Seal CJ, Howes MJ, Kite GC, Okello EJ. In vitro protective effects of Withania somnifera (L.) dunal root extract against hydrogen peroxide and β-amyloid (1-42)-induced cytotoxicity in differentiated PC12 cells. Phytother Res. 2010; 24: 1567-1574.
58. Shah N, Singh R, Sarangi U, Saxena N, Chaudhary A, Kaur G, et al. Combinations of Ashwagandha leaf extracts protect brain-derived cells against oxidative stress and induce differentiation. PLoS One. 2015; 10(3): e0120554.
59. Rahman MA, Hossain S, Abdullah N, Aminudin N. Validation of Ganoderma lucidum against hypercholesterolemia and Alzheimer's disease. Eur J Biol Res. 2020; 10: 314-325.
60. Sohn E, Lim HS, Kim YJ, Kim BY, Jeong SJ. Annona atemoya leaf extract improves scopolamine-induced memory impairment by preventing hippocampal cholinergic dysfunction and neuronal cell death. Int J Mol Sci. 2019; 20: 3538.
61. Puangmalai N, Thangnipon W, Soi-Ampornkul R, Suwanna N, Tuchinda P, Nobsathian S. Neuroprotection of N-benzylcinnamide on scopolamine-induced cholinergic dysfunction in human SH-SY5Y neuroblastoma cells. Neural Regen Res. 2017; 12: 1492-1498.
62. Gupta M, Kaur G. Withania somnifera (L.) Dunal ameliorates neurodegeneration and cognitive impairments associated with systemic inflammation. BMC Complem Altern Med. 2019; 19: 217.
63. Saykally JN, Hatic H, Keeley KL, Jain SC, Ravindranath V, Citron BA. Withania somnifera extract protects model neurons from in vitro traumatic injury. Cell Transplant. 2017; 26: 1193-1201.
How to Cite
Visweswari, G.; Christopher, R.; Rajendra, W. Withania Somnifera Against Glutamate Excitotoxicity and Neuronal Cell Loss in a Scopolamine-Induced Rat Model of Alzheimer’s Disease. European Journal of Biological Research 2021, 11, 156-167.
Research Articles