Effect of hydrogen sulfide on aβ25-35 -induced autophagy in mouse neuro-2a cells / 第二军医大学学报

ABSTRACT

Objective To investigate thêoeffect of exogenous hydrogen sulfide on Aβ25-35-induced autophagy in mouse Neuro-2a cells and the underlying mechanism. Methods The Neuro-2a cells were randomly divided into control group. Aβ25-35 treatment group. Aβ25-35 + NaHS group. Aβ25-35 n3-MA (3-methyl adenine) group. NaHS group and Aβ25-35 + NaHS + LY294002 group. In Aβ25-35+ NaHS group and Aβ25-35 +3-MA group. NaHS and 3-MA were used for pretreatment for 2 h. which was followed by 24 h co-incubation with Aβ5-35; in Aβ25-35 + NaHS+LY294002 group. after pretreatment with NaHS. LY294002 was administered for 0. 5 h before Aβ25-35 was given. MTT assay was used to detect the viability of Neuro-2a cells. The expression of the autophagy related proteins including Beclin-1. LC3 and P62was measured by Western blotting analysis. Immunofluorescence was used to detect the expression and distribution of LC3. The formation ofautophagosomes was determined by transmission electron microscopy (TEM). Results (1) Compared with control group. Aβ25-35 group had significantly declined cell viability (P<0. 05). significantly increased expression of Beclin-1 and LC3H and decreased P62 expression (P<0. 05). accompanied by increased autophagsomes under fluorescencemicroscope and electron microscope. (2) Compared with Aβ25-35 group. the cell viability was significantly increased in Aβ25-35 + 3-MA and Aβ25-35 +NaHS groups (P< 0. 05). and expression of Beclin-1 and LC3H was decreased and expression of P62 was increased (P<0. 05). accompanied by reduced autophagosomes. (3) The expression of p-Akt and p-mTOR in Aβ25-35 +NaHS group was significantly higher than that in Aβ25-35 group (P<0. 05); however. the expression of p-Akt and p-mTOR was significantly reduced after given the specific PI3K/Akt pathway inhibitor LY294002 compared with Aβ25-35 +NaHS group (P<0. 05). Conclusion The exogenous H2S can protect against Aβ25-35 -induced cytotoxicity. which is probably related to the activation of PI3K/Akt/mTOR pathways and the inhibition of Aβ25-35 -induced cell autophagy.