Scutellaria barbata Flavonoids Improve the Composited Aβ-induced Abnormal Changes in Glial Cells of the Brains of Rats.

Aim: It has been reported that glial cells are involved in Alzheimer's disease (AD). In our previous research, Scutellaria barbata flavonoids (SBFs) were found to protect the AD-like rats from neuronal disorder and memory impairment; however, the effect of SBFs on the glial cells disorder in AD-like rats has been less studied. The effects of SBFs on astrocytes (ASs), microglial cells (MGs), and oligodendrocytes (Ols), as well as heat shock protein 70 (Hsp70) and apolipoprotein E (ApoE), were investigated in the present study.

Methods: The successful model rats, screened by Morris water maze, were orally administrated daily with 35, 70, and 140 mg/kg SBFs for 36 d. The number of brain astrocytes (ASs), microglial cells (MGs), and oligodendrocytes (Ols) was examined by immunohistochemistry. The expressions of cortical glial fibrillary acidic protein (GFAP), leukocyte common antigen (LCA) (CD45), Claudin 11, and heat shock protein 70 (Hsp70) protein were assayed by Western blotting, and the expression of apolipoprotein E (ApoE) mRNA was analyzed by real-time quantitative polymerase chain reaction (qPCR).

Results: Compared with the sham-operated group, the number of ASs and MGs in the brain was significantly increased in the model group (P<0.05, P<0.01), accompanied by an increase in the expressions of GFAP, CD45, Hsp70 protein, and ApoE mRNA (P<0.05, P<0.01). Both Ols number and the expression of Claudin 11 protein decreased in the brain in the model group (P<0.05, P<0.01). However, the above-mentioned abnormal changes induced by composited Aβ were differently reversed by the treatment of SBFs at three doses of 35, 70, and 140 mg/kg (P<0.05, P<0.01).

Conclusion: SBFs can dramatically improve the abnormal changes in glial cells of the brains of rats, induced by composited Aβ, which may be utilized as a helpful treatment for neurodegenerative diseases.