Effects of presenilin-1 V97L mutation on neprilysin expressing in SH-SYSY cell / 中华神经科杂志

ABSTRACT

Objective To study the mechanisms of increasing amyloid [β1-42 (Aβ42) level by presenilin-1 (PS-1) mutation of V97L.Methods Expression level of neprilysin (NEP) in nontransfected, or mock vector, wild type (wt) PS-1 and V97L-PS-1-transfected SH-SY5Y cells were assessed by reverse transcriptional-polymerase chain reaction (RT-PCR) and Western blot.The level of Aβ42 was also assessed by enzyme linked immunosorbent assay (ELISA).Results The mRNA level of NEP was decreased significantly in PS-1 V97L transfected cells (0.650 ± 0.010) compared to that in normal cells (1.090 ± 0.015), wt PS-1 gene (1.040 ± 0.021) and mock (1.080 ± 0.020) stably transfected cell lines (t = 9.236, 10.452, 5.678; all P < 0.01).Although there was a decreased tendency in the protein expression of NEP in PS-Ⅰ V97L transfected cells (1.000 ± 0.126)compared to that in normal cells (1.020 ± 0.110), wt PS-1 gene (1.040 ±0.110), mock (2.130 ±0.130) stably transfected cell lines, nosignificant differences were found.The expression of Aβ42 was increased significantly in PS-1 V97L transfected cells compared to other cell lines (t = 2.109, 3.355, 3.976; all P < 0.01).Conclusions PS-1 V97L mutation can decrease the transcription of NEP, however, in contrast, this mutation also resulted in increased Aβ42.The mechanism needs further analysis.