Genistein inhibits Aβ1-40-induced astrogliosis: A three-dimensional confocal morphometric analysis
(English)Manuscript (preprint) (Other academic)
Astrocytes are highly involved in regulation and homeostasis of the extracellular environment in the healthy brain. In pathological conditions, these cells play a major role in the inflammatory response seen in CNS tissues, which is called reactive astrogliosis and includes hypertrophy, proliferation, and remodeling. Here, we performed 3D confocal microscopy to evaluate the morphology of reactive glial fibrillary acidic protein (GFAP-positive) astrocytes in an animal model of Alzheimer’s disease, and we also assessed the effect of the antiinflammatory agent genistein on amyloid-beta-induced astrogliosis. In 50 astrocytes/animal, we measured the area and volume of the nucleus, cell body, astrocyte (soma and branches) and territory (tissue covered by each astrocyte), and total length of the branches. Moreover, we quantified the intensity of GFAP immunoreactivity in the hippocampus. Injecting amyloid beta (Aβ)1–40 into the brain caused astrogliosis, observed as significantly higher GFAP intensity in the hippocampus, and also led to significant enlargement of astrocytes in this area, indicated by increased values for all the above-mentioned parameters. In Aβ1–40-injected rats pretreated with genistein, GFAP intensity was decreased to the level seen in the shamoperated group, and Aβ1–40-induced enlargement of astrocytes was significantly inhibited. Interestingly, genistein also ameliorated the astrogliosis that was initiated by mechanical injury caused by insertion of the injection needle into the brain tissue. This was indicated by the observation that the mean cell body volume and area of astrocytes were significantly smaller in the genistein-treated rats, even in comparison with the sham-operated animals.
Alzheimer’s disease; astrocytes; amyloid beta; genistein; gliosis
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:liu:diva-77172OAI: oai:DiVA.org:liu-77172DiVA: diva2:525325