Effect and mechanism of dexmedetomidine in alleviating cognitive dysfunction in neonatal rats via the JAK2/STAT3 signaling pathway
10.11855/j.issn.0577-7402.0907.2025.0528
- VernacularTitle:右美托咪定通过JAK2/STAT3信号通路缓解新生大鼠认知功能障碍的作用及其机制
- Author:
Jun-Xian BAO
1
;
Yu-Lan HONG
;
Yun-Tian FENG
Author Information
1. 镇江市中医院麻醉科,江苏 镇江 212000
- Keywords:
dexmedetomidine;
sevoflurane;
neonatal rats;
cognitive dysfunction;
Janus kinase 2/signal transducer and activators of transcription 3 signaling pathway
- From:
Medical Journal of Chinese People's Liberation Army
2025;50(10):1315-1324
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the effect and mechanism of dexmedetomidine(Dex)in alleviating sevoflurane(Sev)-induced cognitive dysfunction in neonatal rats via the Janus kinase 2/signal transducer and activators of transcription 3(JAK2/STAT3)signaling pathway.Methods A total of 50 neonatal Sprague-Dawley(SD)rats were randomly divided into control group,model group,Dex group,AG490 group,and Colivelin group,with 10 rats in each group.Except for control group,the rats in the other four groups were used to construct a model of cognitive dysfunction in neonatal rats by inhaling Sev.Before modeling,Dex group was intraperitoneally injected with 20 μg/kg Dex;AG490 group was intraperitoneally injected with 20 μg/kg Dex and 1 mg/kg AG490;Colivelin group was intraperitoneally injected with 20 μg/kg Dex,1 mg/kg AG490,and 1 mg/kg Colivelin;control group and model group were intraperitoneally injected with an equal doses of physiological saline.The novel object recognition test and step-down test were used to detect the cognitive,learning,and memory functions of neonatal rats.TUNEL method was used to detect the cell apoptosis rate in the hippocampus.Rhodamine 123 staining was used to detect the mitochondrial membrane potential in the hippocampus.ELISA method was used to detect the levels of malondialdehyde(MDA)and superoxide dismutase(SOD)in the hippocampus.DHE probe method was used to detect the intracellular reactive oxygen species(ROS)content.qRT-PCR was used to detect the mRNA expression levels of phosphorylated JAK2(p-JAK2),phosphorylated STAT3(p-STAT3),Synapsin-I,brain-derived neurotrophic factor(BDNF),B-cell lymphoma-2(Bcl-2),and Bcl-2-associated X protein(Bax).Western Blotting was used to detect the protein expression levels of p-JAK2,p-STAT3,JAK2,and STAT3 in the hippocampus.Results Compared with control group,model group showed cognitive and memory impairment,significantly increased apoptosis rate,increased levels of ROS and MDA,decreased SOD level,decreased mRNA expression levels of p-JAK2,p-STAT3,Synapsin-I,BDNF,and Bcl-2,increased Bax mRNA expression level,decreased ratios of p-JAK2/JAK2 and p-STAT3/STAT3,and decreased mitochondrial membrane potential in the hippocampus(P<0.05).Compared with model group,Dex,AG490,and Colivelin groups showed significantly improved cognitive and memory impairment,significantly decreased apoptosis rate,decreased levels of ROS and MDA,increased SOD level,increased mRNA expression levels of p-JAK2,p-STAT3,Synapsin-I,BDNF,and Bcl-2,decreased Bax mRNA level,increased ratios of p-JAK2/JAK2 and p-STAT3/STAT3,and increased mitochondrial membrane potential in the hippocampus(P<0.05).Compared with Dex group,AG490 and Colivelin groups exhibited cognitive and memory impairment,significantly increased apoptosis rate,increased levels of ROS and MDA,decreased SOD level,decreased mRNA expression levels of p-JAK2 and p-STAT3,Synapsin-I,BDNF,and Bcl-2,increased Bax mRNA expression level,decreased ratios of p-JAK2/JAK2 and p-STAT3/STAT3,and decreased mitochondrial membrane potential in the hippocampus(P<0.05).Compared with AG490 group,Colivelin group showed significantly improved cognitive and memory impairment,significantly decreased apoptosis rate,decreased levels of ROS and MDA,increased SOD level,decreased mRNA expression levels of p-JAK2 and p-STAT3,Synapsin-I,BDNF,and Bcl-2,increased Bax mRNA expression level,decreased ratios of p-JAK2/JAK2 and p-STAT3/STAT3,and increased mitochondrial membrane potential in the hippocampus,with statistically significant differences(P<0.05).Conclusion Dex can inhibit the oxidative stress in the hippocampus of brain tissue in Sev-induced neonatal rats and improve their cognitive,learning,and memory impairment,which may be related to the activation of JAK2/STAT3 signaling pathway.