Neuroprotective role of Diosgenin, a NGF stimulator, against Aβ (1-42) induced neurotoxicity in animal model of Alzheimer's disease

Metab Brain Dis. 2022 Feb;37(2):359-372. doi: 10.1007/s11011-021-00880-8. Epub 2022 Jan 13.

Abstract

Diosgenin is a neurosteroid derived from the plants and has been previously reported for its numerous health beneficial properties, such as anti-arrhythmic, hypolipidemic, and antiproliferative effects. Although several studies conducted earlier suggested cognition enhancement actions of diosgenin against neurodegenerative disorders, but the molecular mechanisms underlying are not clearly understood. In the present study, we investigated the neuroprotective effect of diosgenin in the Wistar rats that received an intracerebroventricular injection of Amyloid-β (1-42) peptides, representing a rodent model of Alzheimer's disease (AD). Animals were treated with 100 and 200 mg/kg/p.o of diosgenin for 28 days, followed by Amyloid-β (1-42) peptides infusion. Animals were assessed for the spatial learning and memory by using radial arm maze and passive avoidance task. Subsequently, animals were euthanized and brains were collected for biochemical estimations and histopathological studies. Our results revealed that, diosgenin administration dose dependently improved the spatial learning and memory and protected the animals from Amyloid-β (1-42) peptides induced disrupted cognitive functions. Further, biochemical analysis showed that diosgenin successfully attenuated Amyloid-β (1-42) mediated plaque load, oxidative stress, neuroinflammation and elevated acetylcholinesterase activity. In addition, histopathological evaluation also supported neuroprotective effects of diosgenin in hippocampus of rat brain when assessed using hematoxylin-eosin and Cresyl Violet staining. Thus, the aforementioned effects suggested protective action of diosgenin against Aβ (1-42) induced neuronal damage and thereby can serve as a potential therapeutic candidate for AD.

Keywords: Alzheimer’s disease; Amyloid β (1–42) peptide; Diosgenin; Neuroinflammation; Oxidative stress; Plaque load.

MeSH terms

  • Acetylcholinesterase
  • Alzheimer Disease* / chemically induced
  • Alzheimer Disease* / drug therapy
  • Amyloid beta-Peptides / metabolism
  • Amyloid beta-Peptides / toxicity
  • Animals
  • Diosgenin* / adverse effects
  • Disease Models, Animal
  • Hippocampus / metabolism
  • Maze Learning
  • Nerve Growth Factor
  • Neuroprotective Agents* / pharmacology
  • Neuroprotective Agents* / therapeutic use
  • Peptide Fragments / toxicity
  • Rats
  • Rats, Wistar

Substances

  • Amyloid beta-Peptides
  • Neuroprotective Agents
  • Peptide Fragments
  • Nerve Growth Factor
  • Acetylcholinesterase
  • Diosgenin