Lipoxin A4 methyl ester protects PC12 cells from ketamine-induced neurotoxicity via the miR-22/BAG5 pathway

Paresthesia in dentistry: The ignored neurotoxicity of local anesthetics

Local anesthetics are frequently used by dentists to relieve localized discomfort of the patient and improve treatment conditions. The risk of paresthesia after local anesthesia is frequently encountered in dental clinics. The neurotoxicity of local anesthetics is a disregarded factor in paresthesia. The review summarizes the types of common local anesthetics, incidence and influencing factors of paresthesia after local anesthesia, and systematically describes the neurotoxicity mechanisms of dental local anesthetic. Innovative strategies may be developed to lessen the neurotoxicity and prevent paresthesia following local anesthesia with the support of a substantial understanding of paresthesia and neurotoxicity.

Lipoxin A4 methyl ester attenuated ketamine-induced neurotoxicity in SH-SY5Y cells via regulating leptin pathway

Ketamine, the widely used intravenous anesthetic, has been reported to cause neurotoxicity and disturbs normal neurogenesis. However, the efficacy of current treatment strategies targeting ketamine's neurotoxicity remains limited. Lipoxin A4 methyl ester (LXA4 ME) is relatively stable lipoxin analog, which serves an important role in protecting against early brain injury. The purpose of this study was to investigate the protective effect of LXA4 ME on ketamine-caused cytotoxicity in SH-SY5Y cells, as well as the underlying mechanisms. Cell viability, apoptosis and endoplasmic reticulum stress (ER stress) were detected by adopting experimental techniques including CCK-8 assay, flow cytometry, western blotting and transmission electron microscope. Furthermore, examining the expression of leptin and its receptor (LepRb), we also measured the levels of activation of the leptin signaling pathway. Our results showed that LXA4 ME intervention promoted the cell viability, inhibited cell apoptosis, and reduced the expression of ER stress related protein and morphological changes induced by ketamine. In addition, inhibition of leptin signaling pathway caused by ketamine could be reversed by LXA4 ME. However, as the specific inhibitor of leptin pathway, leptin antagonist triple mutant human recombinant (leptin tA) attenuated the cytoprotective effect of LXA4 ME against ketamine-induced neurotoxicity. In conclusion, our findings demonstrated LXA4 ME could exert a neuroprotective effect on ketamine-induced neuronal injury via activation of the leptin signaling pathway.

LncRNA TUG1 Promoted Stabilization of BAG5 by Binding DDX3X to Exacerbate Ketamine-Induced Neurotoxicity

As a clinically widely used anesthetic, ketamine (KET) has been reported to cause neurotoxicity in patients. Our work aimed to probe the function of long-chain non-coding RNA taurine-upregulated gene 1 (lncRNA TUG1) in KET-induced neurotoxicity. HT22 cells were subjected to KET to build the cell model. 3-(4, 5-Dimethylthiazolyl2)-2, 5-diphenyltetrazolium bromide (MTT) assay was employed to determine cell viability. Additionally, cell apoptosis was evaluated by flow cytometry. The binding relationships among TUG1, DEAD-box RNA helicase 3X (DDX3X), and Bcl-2-associated athanogene 5 (BAG5) were verified by RIP and RNA pull-down assays. Cell viability was impaired and cell apoptosis was increased in KET-treated HT22 cells accompanied by increased TUG1, DDX3X, and BAG5 expressions. TUG1 knockdown dramatically enhanced cell viability and repressed the of KET-induced apoptosis in HT22 cells, while TUG1 overexpression presented the opposite effects. In addition, we found that TUG1 promoted DDX3X expression via directly binding with DDX3X. As expected, DDX3X overexpression abolished the palliative effect of TUG1 knockdown on KET-induced neurotoxicity. Further research proved that TUG1 increased the stability of BAG5 through interacting with DDX3X. Finally, as expected, the moderating effect of TUG1 knockdown on KET-induced neuron injury was abolished by BAG5 overexpression. Taken together, TUG1 promoted BAG5 expression by binding DDX3X to exacerbate KET-induced neurotoxicity.