Altered Wnt Signaling Pathway in Cognitive Impairment Caused by Chronic Intermittent Hypoxia: Focus on Glycogen Synthase Kinase-3β and β-catenin / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Cognitive impairment is a severe complication caused by obstructive sleep apnea (OSA). The mechanisms of causation are still unclear. The Wnt/β-catenin signaling pathway is involved in cognition, and abnormalities in it are implicated in neurological disorders. Here, we explored the Wnt/β-catenin signaling pathway abnormalities caused by chronic intermittent hypoxia (CIH), the most characteristic pathophysiological component of OSA.</p><p><b>METHODS</b>We divided 32 4-week-old male C57/BL mice into four groups of eight each: a CIH + normal saline (NS) group, CIH + LiCl group, sham CIH + NS group, and a sham CIH + LiCl group. The spatial learning performance of each group was assessed by using the Morris water maze (MWM). Protein expressions of glycogen synthase kinase-3β (GSK-3β) and β-catenin in the hippocampus were examined using the Western blotting test. EdU labeling and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling staining methods were used, respectively, to determine the proliferation and apoptosis of neurons in the hippocampal dentate gyrus region.</p><p><b>RESULTS</b>Mice exposed to CIH showed impaired spatial learning performance in the MWM, including increased mean escape latencies to reach the target platform, decreased mean times passing through the target platform and mean duration in the target quadrant. The GSK-3β activity increased, and expression of β-catenin decreased significantly in the hippocampus of the CIH-exposed mice. Besides, CIH significantly increased hippocampal neuronal apoptosis, with an elevated apoptosis index. Meanwhile, LiCl decreased the activity of GSK-3β and increased the expression of β-catenin and partially reversed the spatial memory deficits in MWM and the apoptosis caused by CIH.</p><p><b>CONCLUSIONS</b>Wnt/β-catenin signaling pathway abnormalities possibly play an important role in the development of cognitive deficits among mice exposed to CIH and that LiCl might attenuate CIH-induced cognitive impairment via Wnt/β-catenin signaling pathway.</p>

Effects of Continuous Positive Airway Pressure on Cognitive Deficits in Middle-aged Patients with Obstructive Sleep Apnea Syndrome: A Meta-analysis of Randomized Controlled Trials / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Current views on continuous positive airway pressure (CPAP) treatment to improve the cognitive deficits of patients with obstructive sleep apnea syndrome (OSAS) are controversial, so we performed a meta-analysis.</p><p><b>METHODS</b>A comprehensive literature search was undertaken in PubMed, CINAHL, Medline, PsycInfo, EMBASE, Cochrane Library, CNKI, WanFang, VIP, and CBMdisc for studies published from June 1971 to July 2014. The outcome measures included neuropsychological tests of the 7 cognitive domains detailed below.</p><p><b>RESULTS</b>After screening the titles and abstracts and thoroughly reading the full text, we obtained 13 studies with little risk of bias that incorporated 1744 middle-aged obese participants with mild to severe OSAS. The studies were published from 1994 to 2012. Treatment durations varied from 1 to 24 weeks. The effect sizes of attention, vigilance, processing speed, working memory, memory, verbal fluency, and visuoconstructive skills domains were -0.10 (P = 0.24), -0.12 (P = 0.04), -0.08 (P = 0.16), 0.00 (P = 0.95), -0.04 (P = 0.30), -0.06 (P = 0.34), and -0.01 (P = 0.92), respectively.</p><p><b>CONCLUSIONS</b>Cognition partially improved in patients with OSAS after CPAP treatment. The only domain with significant improvement was vigilance. Rigorous randomized controlled trials need to be performed to obtain clear results.</p>

A study of dynamic changes of NO,NOS in serum and CSF in patients with CNS infection / 中国基层医药

Objective To observe the dynamic changes of NO,NOS in serum and CSF in patients with CNS infection and lay an experimental basis for discrimination of CNS infection due to different agents.Methods The method of nitrate redutase and the method of chromometry were employed to measure NO,NOS in serum and CSF at different time.The dynamic changes of NO,NOS in serum were observed on admission,on 3,5,9,14 day after admission.The dynamic changes of NO,NOS in CSF before treatment and two weeks after treatment were ob- served,too.Results There were no difference between the the concentration of NO and the vigor of total NOS in serum and in CSF of viral meningitis,bacterial meningitis and tubercular meningitis patients due to different agents. Conclusion The changes of the concentration of NO in serum and CSF,the vigor of total NOS in serum and CSF could not he seen as laboratory basis for discrimination of CNS infection due to different agents.