Puerarin may exert protective effects against Alzheimer's disease. - GreenMedInfo Summary
Puerarin inhibitsβ‑amyloid peptide 1‑42‑induced tau hyperphosphorylation via the Wnt/β‑catenin signaling pathway.
Mol Med Rep. 2017 Dec ;16(6):9081-9085. Epub 2017 Oct 3. PMID: 28990074
Excessive tau protein phosphorylation is important in the pathogenesis and early abnormal signal transduction of Alzheimer's disease. Excessive phosphorylation of microtubules is associated with tau accumulation, which induces the formation of neurofibrillary tangles in neurons, leading to synaptic damage and ultimately, neurodegeneration. The present study aimed to investigate the possible mechanism underlying the inhibitory effects of puerarin onβ‑amyloid peptide (Aβ)1‑42‑induced tau protein hyperphosphorylation in SH‑SY5Y cells. Following various treatments, the viability of SH‑SY5Y cells was determined using the MTT assay, and cell morphology was observed under an inverted fluorescence microscope. Western blotting was used todetect tau phosphorylation, and the protein expression levels of glycogen synthase kinase (GSK)‑3β, phosphorylated (p)‑GSK‑3β (Ser9), β‑catenin and cyclin D1, which are the key factors mediating the Wnt/β‑catenin signaling pathway in SH‑SY5Y cells. The results demonstrated that puerarin reversed the Aβ1‑42‑induced decrease in SH‑SY5Y cell viability. In addition, puerarin inhibited the degree of Aβ1‑42‑induced tau phosphorylation at Ser396, Ser199 and Thr231 in SH‑SY5Y cells, and reduced the expression of GSK‑3β by increasing the expression of p‑GSK‑3β (Ser9). Furthermore, puerarin increased the protein expression levels of β‑catenin and cyclin D1, which are key factors involved in the Wnt/β‑catenin signaling pathway. The results of the present study demonstrated that puerarin may attenuate Aβ1‑42‑induced tau hyperphosphorylation in SH‑SY5Y cells, by inhibiting the expression of GSK‑3β and activating the Wnt/β‑catenin signaling pathway; therefore, puerarin may exert protective effects against Alzheimer's disease.