Modulation of DNMT1 in LPS-induced Microglia

Rat microglial cell line (highly aggressive proliferating immortalized, HAPI) provided by BeNa Culture Collection (Xinyang, Henan, China) was cultured in high-glucose Dulbecco’s modified Eagle’s medium containing 10% fetal bovine serum (Thermo Fisher Scientific, Waltham, MA, USA) in an incubator with 5% CO₂ and 95% humidity.
Cells were allocated into the following 7 groups: control group, LPS group (treated with 100 ng/mL LPS for 24 h), LPS + si-NC group (transfected with si-NC for 24 h, followed by LPS treatment for 24 h), LPS + si-DNMT1 group (transfected with si-DNMT1 for 24 h, followed by LPS treatment for 24 h), LPS + oe-NC group (transfected with oe-NC for 24 h, followed by LPS treatment for 24 h), LPS + oe-DNMT1 group (transfected with oe-DNMT1 for 24 h, followed by LPS treatment for 24 h), and LPS + si-DNMT1 + IGF-1 group (based on the LPS + si-DNMT1 group, cells were treated with Akt activator (insulin-like growth factor 1, IGF-1, 100 ng/mL) for 1 h [48 (link)]. IGF-1 (Enzyme-linked Biotechnology, Shanghai, China), si-DNMT1, si-NC, oe-DNMT1, and oe-NC (all from GenePharma) were transfected into HAPI cells using Lipofectamine 2000 (Invitrogen, Carlsbad, CA, USA) at 50 nM.