Abstract

To explore the protective effect of Cornus officinalis extracts on Alzheimer’s disease cell injury models and its underlying molecular mechanism. Pheochromocytoma cells were treated with 20 μM amyloid beta-peptide 25-35 to establish an Alzheimer’s disease cell injury model in vitro, which was recorded as amyloid beta-peptide 25-35 group. Cells affected by amyloid beta-peptide 25-35 were treated with different-doses of Cornus officinalis extracts and recorded as low-dose Cornus officinalis extracts group, medium-dose Cornus officinalis extracts group and high-dose Cornus officinalis extracts group. Pheochromocytoma cells transfected with si-NC/si-long non-coding RNA Rpph1, treated with 20 μM amyloid beta-peptide 25-35 and 80 mg/ml of Cornus officinalis extracts were recorded as high-dose Cornus officinalis extracts+si-NC group, high-dose Cornus officinalis extracts+si-long non-coding RNA Rpph1 group. Cell viability and apoptosis were examined using cell counting kit-8 assay and flow cytometry. Protein expression was tested by Western blot. Malondialdehyde, superoxide dismutase and catalase levels were assessed by measuring cell oxidative stress. Amyloid beta-peptide, tumor necrosis factor-alpha, interleukin-6 and interferon gamma levels were examined using enzyme-linked immunosorbent assay. Long non-coding RNA Rpph1 expression was detected using quantitative reverse transcriptase polymerase chain reaction. Amyloid beta-peptide 25-35 treatment decreased Pheochromocytoma cell viability, CyclinD1, superoxide dismutase, catalase and long non-coding RNA Rpph1 levels, while increased apoptosis rate, cleaved-caspase-3, malondialdehyde, amyloid beta-peptide, tumor necrosis factor-alpha, interleukin-6 and interferon gamma levels. After treatment with different-doses of Cornus officinalis extracts, cell viability, CyclinD1, superoxide dismutase, catalase and long non-coding RNA Rpph1 levels were enhanced, while apoptosis rate, cleaved-caspase-3, malondialdehyde, Aβ, tumor necrosis factor-alpha, interleukin-6 and interferon gamma levels were reduced in pheochromocytoma cells treated with amyloid beta-peptide 25-35. Downregulation of long non-coding RNA Rpph1 reversed the inhibitory effect of Cornus officinalis extracts on cell injury. Cornus officinalis extracts relieved amyloid beta-peptide 25-35-induced nerve cell injury by upregulating long non-coding RNA Rpph1, suggesting that Cornus officinalis extracts might be used in Alzheimer's disease treatment.