Objective: To investigate the mechanism of miR-223 on the apoptosis of Aβ1-42-induced hippocampal neurons. Methods: The hippocampal neurons of newborn SD rats were cultured in vitro, and randomly divided into blank group(without any transfection), negative group(transfected with miR-NC), miR-223-m group(transfected with miR-223 mimics), miR-223-m+LV group(transfected with miR-223 mimics+lentiviral skeleton), miR-223-m+LV-RhoB group(transfected with miR-223 mimics+Rhob overexpression vector). The expression of miR-223 and RhoB in Aβ1-42-induced hippocampal neurons was detected by qRT-PCR and Western blotting, the survival rate of Aβ1-42-induced hippocampal neurons with different concentrations was detected by MTT assay, and the apoptosis of hippocampal neurons was detected by flow cytometry assay. Dual-luciferase reporter gene was used to detect the fluorescence activity of cells. Results: Aβ1-42 could significantly inhibit the survival rate of hippocampal neurons in a dose-dependent manner, and it also decreased the relative expression of miR-223 and increased the expression level of RhoB. 30 μmol·L-1Aβ1-42 oligopeptide fragment was selected for further grouping. After incubated for 48 hours with 30 μmol·L-1Aβ1-42, the apoptosis rate of the miR-223-m group was lower than that of blank group and negative group, and the apoptosis rate of the miR-223-m+LV-RhoB group was increased compared with the miR-223-m group and the miR-223-m+LV group(P<0.05). In addition, the expression of RhoB protein, Bax and caspase-3 protein was decreased and the expression of Bcl-2 protein was increased in the miR-223-m group compared with the blank group and the negative group(P<0.05), while the expression of Rhob, Bax and caspase-3 protein increased and the expression of Bcl-2 protein decreased in the miR-223-m+LV-RhoB group compared with the miR-223-m group and the miR-223-m+LV group(P<0.05). Dual-Luciferase reporter gene analysis showed that the miR-223 mimics and wild type RhoB 3'UTR could inhibit luciferase activity(P<0.05). Conclusion: miR-223 can inhibit apoptosis of Aβ1-42-induced hippocampal neurons by targeting RhoB.
 ZHU J B,TAN C C,TAN L,et al.State of play in Alzheimer's disease genetics[J].J Alzheimers Dis,2017,58(3):631-659.
 HANE F T,LEE B Y,LEONENKO Z.Recent progress in Alzheimer's disease research,part 1:pathology[J].J Alzheimers Dis,2017,57(1):1-28.
 VIOLA K L,KLEIN W L.Amyloid β oligomers in Alzheimer's disease pathogenesis,treatment,and diagnosis[J].Acta Neuropathol,2015,129(2):183-206.
 TIWARI A,MUKHERJEE B,DIXIT M.MicroRNA key to angiogenesis regulation:miRNA biology and therapy[J].Curr Cancer Drug Targets,2018,18(3):266-277.
 JIA L H,LIU Y N.Downregulated serum miR-223 servers as biomarker in Alzheimer's disease[J].Cell Biochem Funct,2016,34(4):233-237.
 SERPENTE M,FENOGLIO C,D'ANCA M,et al.MiRNA profiling in plasma neural-derived small extracellular vesicles from patients with Alzheimer's disease[J].Cells,2020,9(6):1443.
 LEE S J,NAM E,LEE H J,et al.Towards an understanding of amyloid-β oligomers:characterization,toxicity mechanisms,and inhibitors[J].Chem Soc Rev,2017,46(2):310-323.
 MARLOW L A,BOK I,SMALLRIDGE R C,et al.RhoB upregulation leads to either apoptosis or cytostasis through differential target selection[J].Endocr Relat Cancer,2015,22(5):777-792.
 NIN M,ZHANG J G,HUANG L,et al.A Rho-kinase inhibitor reverses learning and memory deficits in a rat model of chronic cerebral ischemia by altering Bcl-2/Bax-NMDAR signaling in the cerebral cortex[J].J Pharmacol Sci,2018,138(2):107-115.
 ZISSIMOPOULOS J M,BARTHOLD D,BRINTON R D,et al.Sex and race differences in the association between statin use and the incidence of Alzheimer disease[J].JAMA Neurol,2017,74(2):225-232.
 BARBERAN S,MCNAIR K,IQBAL K,et al.Altered apoptotic responses in neurons lacking RhoB GTPase[J].Eur J Neurosci,2011,34(11):1737-1746.
 WANG B,CAO X,LIN J,et al.Up-regulation of microRNA-223 inhibits brain injury and hippocampal neuron apoptosis of rats after febrile seizure through the NLRP3-Caspase-1 signaling pathway[J].Biomed Pharmacother,2019,114(6):108683.
 MANCUSO R,AGOSTINI S,HERNIS A,et al.Circulatory miR-223-3p discriminates between Parkinson's and Alzheimer's patients[J].Sci Rep,2019,9(1):9393.