Analysis of the Protective Potential of the Amniotic Membrane in an In Vitro Experimental Model of Demyelination in Mouse Brain Organotypic Slices

Amniotic membrane (AM) is a biological material recognized for its regenerative, anti-inflammatory, and immunomodulatory properties, constituting a promising approach for the treatment of neurodegenerative diseases, such as demyelinating diseases. Some neurodegenerative diseases, such as Multiple Sclerosis (MS), occur with demyelination, which is a process characterized by the loss of myelin, a structure responsible for the adequate conduction of nerve impulses, compromising neuronal functionality. In this context, this study aimed to investigate the efficacy of AM in protecting nervous tissue against the demyelinating effects of lysophosphatidylcholine (LPC, lysolecithin), using organotypic brain slices from C57BL/6 mice as an in vitro experimental model. Four experimental groups were established: C−H (healthy slices), C- DEM (slices demyelinated with LPC), C-AM (healthy slices with AM), and AM-LPC (slices protected by AM before LPC). The analyses included histological staining (Hematoxylin and Eosin, Luxol Fast Blue), metabolic test with 2,3,5-triphenyltetrazolium chloride (TTC), and Scanning Electron Microscopy (SEM). Results showed that AM preserved myelin and tissue architecture in the challenged slices, while the demyelination group presented microcavitations, structural disorganization, and loss of distinction between white and gray matter. The TTC assay revealed high metabolic activity in the slices protected by AM, in contrast with the low activity in the demyelinated group. SEM analysis reinforced the efficacy of AM, evidencing a preserved organization of the brain parenchyma in slices protected by AM. Thus, the results demonstrate that AM was effective in protecting nervous tissue against the demyelinating effects of lysophosphatidylcholine, preserving myelin, structural organization, and metabolic activity of brain slices, as evidenced by histological, metabolic, and ultrastructural analyses with SEM.