Background Children with multiple exposures to anesthesia and surgery may have an increased risk of developing cognitive impairment. Sevoflurane is a commonly used anesthetic in children. Tau phosphorylation contributes to cognitive dysfunction. We therefore assessed the effects of sevoflurane on Tau phosphorylation and underlying mechanisms in young mice. Methods Six day-old wild-type (WT) and Tau knockout (KO) mice were exposed to sevoflurane. We determined the effects of the sevoflurane anesthesia on Tau phosphorylation, levels of the kinases and phosphatase related to Tau phosphorylation, interleukin-6, and postsynaptic density protein 95 (PSD-95) in hippocampus, and cognitive function in both young WT and Tau KO mice. Results Anesthesia with 3% sevoflurane two hours daily for three days induced Tau phosphorylation (257% versus 100%, P=0.0025, n=6), enhanced activation of glycogen synthase kinase 3β (GSK3β), the kinase related to Tau phosphorylation in the hippocampus of postnatal day 8 WT mice. The sevoflurane anesthesia decreased hippocampus PSD-95 levels and induced cognitive impairment in the postnatal day 31 mice. GSK3β inhibitor lithium inhibited the sevoflurane-induced GSK3β activation, Tau phosphorylation, elevated levels of interleukin-6 and cognitive impairment in the WT young mice. Finally, the sevoflurane anesthesia did not induce an elevation of interleukin-6 levels, reduction in PSD-5 levels in hippocampus, or cognitive impairment in Tau KO young mice. Conclusions These data suggested that sevoflurane induced Tau phosphorylation, GSK3β activation, elevation of interleukin-6 and reduction of PSD-95 levels in hippocampus of young mice, and cognitive impairment in the mice. Future studies will dissect the cascade relationship of these effects.

Demand is increasing for safer inhalational anesthetics for use in pediatric anesthesia. In this regard, researchers have debated whether isoflurane is more toxic to the developing brain than desflurane. In the present study, we compared the effects of postnatal exposure to isoflurane with those of desflurane on long-term cognitive performance and investigated the role of the Akt/GSK3β signaling pathway. Postnatal day 6 (P6) mice were exposed to either isoflurane or desflurane, after which the phosphorylation levels of Akt/GSK3β and learning and memory were assessed at P8 or P31. The phosphorylation levels of Akt/GSK3β and learning and memory were examined after intervention with lithium. We found that isoflurane, but not desflurane, impaired spatial learning and memory at P31. Accompanied by behavioral change, only isoflurane decreased p-Akt (ser473) and p-GSK3β (ser9) expressions, which led to GSK3β overactivation. Lithium prevented GSK3β overactivation and alleviated isoflurane-induced cognitive deficits. These results suggest that isoflurane is more likely to induce developmental neurotoxicity than desflurane in context of multiple exposures and that the Akt/GSK3β signaling pathway partly participates in this process. GSK3β inhibition might be an effective way to protect against developmental neurotoxicity.

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These results indicate that Tan IIA can alleviate sevoflurane-induced neurobehavioral abnormalities and may decrease neuroapoptosis and neuroinflammation.

Intracellular hypochlorite could be rapidly and specifically detected with novel luminescent AF@MOF-801 nanoparticles based on a size-selective effect.

Chiral recognition and quantification of amino acid (AA) enantiomers are of great significance in many fields such as biology and biomedicine. Herein, a general enzyme-driven fluorescent sensing model was proposed...

Sevoflurane exposures were demonstrated to induce neurotoxicity in the developing brain in both human and animal studies. However, there is no effective approach to reverse it. The present study aimed to evaluate the feasibility of utilizing docosahexaenoic acid (DHA) to prevent sevoflurane-induced neurotoxicity. P6 (postnatal 6 days) mice were administrated DHA after exposure to 3% sevoflurane for two hours daily in three consecutive days. Molecular expressions of synaptic makers (PSD95, synaptophysin) and synaptic morphological changes were investigated by Western blot analysis and transmission electron microscopy, respectively. Meanwhile, Morris water maze test was used to assess spatial memory of mice at P31 (postnatal 31 days). DHA restored sevoflurane-induced decreased level of PSD95 and synaptophysin expressions and increased PSD areas and also improved long-term spatial memory. These results suggest that DHA could rescue synaptogenesis impairment and long-term memory deficits in postnatal caused by multiple sevoflurane exposures.

Dexmedetomidine (DEX), a highly specific and selective α2 adrenergic receptor agonist, has been demonstrated to possess potential cardioprotective effects. However, the mechanisms underlying this process remain to be fully illuminated. In the present study, a myocardial infarction (MI) animal model was generated by permanently ligating the left anterior descending coronary artery in mice. Cardiac function and collagen content were evaluated by transthoracic echocardiography and picrosirius red staining, respectively. Apoptosis was determined by the relative expression levels of Bax and Bcl-2 and the myocardial caspase-3 activity. Additionally, nicotinamide adenine dinucleotide phosphate oxidase (NOX)-derived oxidative stress was evaluated by the relative expression of Nox2 and Nox4, along with the myocardial contents of malondialdehyde (MDA) and superoxide dismutase (SOD) activity. It was demonstrated that intraperitoneal DEX treatment (20 µg/kg/day) improved the systolic function of the left ventricle, and decreased the fibrotic changes in post-myocardial infarction mice, which was paralleled by a decrease in the levels of apoptosis. Subsequent experiments indicated that the restoration of redox signaling was achieved by DEX administration, and the over-activation of NOXs, including Nox2 and Nox4, was markedly inhibited. In conclusion, this present study suggested that DEX was cardioprotective and limited the excess production of NOX-derived ROS in ischemic heart disease, implying that DEX is a promising novel drug, especially for patients who have suffered MI.