Effect of Bone Marrow-Derived Mesenchymal Stem Cells on the Hippocampal CA1 Area of Aluminium Chloride-Induced Alzheimer's Disease in Adult Male Albino Rat: A Histological and Immunohistochemical Study

Background: Alzheimer’s disease (AD) is the commonest cause of dementia among the elderly. Aluminium is a toxic metal that primarily affects the hippocampus. Bone marrow-derived mesenchymal stem cells (BM-MSCs) therapy is considered a recent strategy for treatment of several diseases including neurologic disorders.Aim: To study effect of BM-MSCs on CA1 of the experimentally induced AD in adult male albino rat.Materials & Methods: 35 adult male albino rats were divided into a control group and an experimental group which was further subdivided into subgroups E1, E2, E3 & E4. Rats of experimental group received 17 mg/kg of aluminium chloride (AlCl3) orally once daily for 4 weeks. 24 hours after last dose of AlCl3, each rat of subgroups E2 and E3 was once IV injected with 1 ml media and BM-MSCs respectively. Subgroup E4 was the recovery subgroup. Hippocampal CA1 specimens were obtained and processed for histological, immunohistochemical, electron microscopic and morphometric studies. Results: Subgroups E1 and E2 revealed many structural changes as disarrangement of pyramidal cell layer which exhibited deeply stained nuclei and vacuolated cytoplasm. Congo red stain of these subgroups showed Congo red positive pyramidal cells and electron microscopic examination showed swollen destroyed mitochondria and dilated saccules of Golgi stacks. Statistically, there was a highly significant increase in number of neurofibrillary tangles and a highly significant decrease in synaptophysin color intensity. In contrast, these changes were markedly ameliorated in the BM-MSCs-treated subgroup. On the other hand, the recovery subgroup showed persistence of some of the structural changes. Conclusion: BM-MSCs injection can ameliorate AD-like pathology which was induced by AlCl3 in CA1 of adult male albino rats.