Global Proteomic Profile of Aluminum-Induced Hippocampal Impairments in Rats: Are Low Doses of Aluminum Really Safe?

Int J Mol Sci. 2022 Oct 19;23(20):12523. doi: 10.3390/ijms232012523.

Abstract

Hippocampus is the brain area where aluminum (Al) accumulates in abundance and is widely associated with learning and memory. In the present study, we evaluate behavioral, tissue, and proteomic changes in the hippocampus of Wistar rats caused by exposure to doses that mimic human consumption of aluminum chloride (AlCl3) in urban areas. For this, male Wistar rats were divided into two groups: Control (distilled water) and AlCl3 (8.3 mg/kg/day), both groups were exposed orally for 60 days. After the Al exposure protocol, cognitive functions were assessed by the Water maze test, followed by a collection for analysis of the global proteomic profile of the hippocampus by mass spectrometry. Aside from proteomic analysis, we performed a histological analysis of the hippocampus, to the determination of cell body density by cresyl violet staining in Cornu Ammonis fields (CA) 1 and 3, and hilus regions. Our results indicated that exposure to low doses of aluminum chloride triggered a decreased cognitive performance in learning and memory, being associated with the deregulation of proteins expression, mainly those related to the regulation of the cytoskeleton, cellular metabolism, mitochondrial activity, redox regulation, nervous system regulation, and synaptic signaling, reduced cell body density in CA1, CA3, and hilus.

Keywords: aluminum; hippocampus; neurotoxicity.

MeSH terms

  • Aluminum Chloride / toxicity
  • Aluminum Compounds / toxicity
  • Aluminum* / metabolism
  • Aluminum* / toxicity
  • Animals
  • Hippocampus / metabolism
  • Humans
  • Male
  • Proteomics*
  • Rats
  • Rats, Wistar

Substances

  • Aluminum
  • Aluminum Chloride
  • Aluminum Compounds

Grants and funding

R.D.D.-S. received scholarships from the Fundação Amazônia de Amparo a Estudos e Pesquisas (FAPESPA 15/2021). L.O.B. received scholarships from the Brazilian National Council for Scientific and Technological Development (CNPq) from the Brazilian Ministry of Science, Technology, and Innovation. W.A.B.A. received a scholarship from the Coordination for the Improvement of Higher Education Personnel (CAPES) (Financial Code 001). L.E.Q. received a scholarship from the FAPESPA. R.R.L. is a researcher from the CNPq, under grant number 312275/2021–8. The APC was funded by the Pró-Reitoria de Pesquisa e Pós-Graduação from the Federal University of Pará.