Potential contribution of microRNA-125b targeting p38MAPK to relieving intermittent hypoxia-induced dementia of mice models.

INTRODUCTION: The purpose of this investigation was to elucidate whether miR-125b targeting p38MAPK could relieve cognitive impairment of obstructive sleep apnea hypopnea syndrome (OSAHS) mice models.

MATERIAL AND METHODS: The mice models were categorized into untreated control (UC), 10% continuous hypoxic (CH), 10% chronic intermittent hypoxia (CIH) and 5% chronic intermittent hypoxia (CIH) groups. Morris Water Maze, spatial navigation test and spatial probe test were conducted to appraise the learning, memorizing and cognitive abilities of mice models. Moreover, miR-125b and p38MAPK expressions were figured out through performing quantitative real time-polymerase chain reaction (qRT-PCR) and western blotting. The luciferase reporter gene assay was also prepared to validate the targeted relationship between miR-125b and p38MAPK.

RESULTS: Our study results showed that intermittent hypoxia generated more serious cognitive impairment of mice than persistent hypoxia (P < 0.05). Furthermore, miR-125b expression was down-regulated and phospho-p38MAPK expression was up-regulated significantly within intermittent hypoxia-treated mice (P < 0.05). Furthermore, the in-vitro tests exhibited that down-regulated expression of miR-125b and phosphorylation of p38MAPK could promote apoptosis and depress viability and proliferation of SH-SY5Y cells (P < 0.05).

CONCLUSION: miR-125b targeting p38MAPK could regulate cognition of OSAHS mice models by altering neuronal function of mice, which might provide theoretical basis for treating intermittent hypoxia-related dementia.