Objective The aim of this study was to investigate the correlation between the interaction of uric acid and inflammatory factors and hyperuricemia in overweight/obese patients. Methods The personnel with hyperuricemia who underwent physical examination in our hospital from September 2021 to September 2022 were selected as the study subjects, and they were divided into 100 cases of overweight group and 90 cases of obese group according to the BMI index; 120 cases of healthy and non-hyperuricemic personnel were randomly selected as the control group; venous blood of the three groups was collected in 5 mL after 8 h of fasting, and were tested respectively for serum uric acid, lipid indexes and inflammatory factors: IL-6, IL-2, IFN-γ, TNF-α, IL-4, IL-10. Results Glucose, triglycerides, total cholesterol, and LDL were significantly higher in the obese group versus the overweight group (P<0.001), while HDL was significantly lower than the control group (P<0.001), and these changes were more pronounced in the obese group (P<0.001).The Pearson correlation coefficient pointed out that the levels of serum uric acid in patients with hyperuricosuric acid were significantly associated with the pro-inflammatory factors IL- 6, IL-2, IFN-γ, and TNF-α were significantly positively correlated (P<0.001), whereas they were significantly negatively correlated with the anti-inflammatory factors IL-4, IL-10 (P<0.001). Conclusion High uric acid levels in overweight/obese patients can cause enhanced inflammatory responses and reduced expression levels of anti-inflammatory factors, and the interaction between uric acid and pro-inflammatory factors aggravates the condition of patients with hyperuricemia.

ObjectiveTo investigate somatization symptoms in adolescents during frequent earthquakes in Hefei， and to explore their correlation with earthquake experiences. MethodsA cross-sectional survey was used to select 324 adolescents in Hefei as the survey objects. The self-rating scale of somatization symptoms （SSS） and the fatigue intensity scale （FIS） were used to evaluate the somatization symptoms and fatigue degree of middle school students， and multivariate Logistic regression analysis was used to explore the related factors of somatization symptoms and fatigue among middle school students. ResultsA total of 324 adolescents were included， and the overall detection rate of somatization symptoms was 6.5%， and the detection rate of moderate or above fatigue was 20.1%. The results of regression analysis showed that adolescents who were concerned about the earthquake for a longer time （≥1 h） had a higher risk of somatization symptoms （OR=5.430， 95%CI： 1.547-19.058）， and adolescents who received pre-earthquake training had a lower degree of fatigue （OR=0.535， 95%CI： 0.292-0.981） （P<0.05）. ConclusionDuring the frequent earthquakes， adolescents have more somatization symptoms and fatigue. Therefore， it is crucial to enhance health education， reduce the emphasis on event-related reports， and implement earthquake prevention and disaster reduction training to improve the physical and mental health of adolescents.

Dry eye （DE） is a prevalent multifactorial disease of the ocular surface， clinically characterized by tear film homeostasis imbalance accompanied by related ocular surface symptoms. Specifically， the tear film is a thin liquid layer of tears covering the cornea and conjunctiva through blinking， while tear film homeostasis serves as the foundation for maintaining normal ocular surface structure and function. Insufficient tear secretion and excessive tear film evaporation lead to tear hyperosmolarity and the production of inflammatory mediators， disrupting tear film homeostasis and subsequently forming DE. Additionally， cascade reactions are triggered， resulting in a "vicious cycle of DE" that exacerbates the disease severity and prolongs its duration. Therefore， for DE treatment， it is crucial to restore tear film homeostasis and terminate this vicious cycle. Traditional Chinese medicine （TCM）， which differentiates and treats DE based on systemic conditions， often achieves favorable therapeutic outcomes， offering additional treatment options for DE. Studies have demonstrated that TCM can alleviate DE by regulating tear film homeostasis and terminating the vicious cycle. This review systematically summarizes recent basic experimental research in China and abroad on TCM in alleviating DE by regulating tear film homeostasis， aiming to provide a theoretical basis for clinical treatment and an insight for research design.

ObjectiveTo establish a model of dry eye with lung Yin deficiency syndrome in mice. MethodsA total of 40 SPF C57BL/6J mice were assigned via the random number table method into 5 groups （n=8）： Normal control， model control， and high-， medium-， and low-dose （11.7， 5.85， and 2.925 g·kg^-1， respectively） Yangyin Qingfeitang. Mice in the normal control group were fed normally without any intervention. Mice in Yangyin Qingfeitang group and model control group were treated with 0.2% benzalkonium chloride eye drops （5 μL） twice a day and fed in a controlled drying system in a dry environment for 28 days. At the same time， the mice were administrated with thyroxine tablet solution by gavage and placed in a glass fumigation tank （SO₂ concentration： 0.5 g·m^-3） for 14 days. After 4 weeks， mice in Yangyin Qingfeitang groups were treated with Yangyin Qingfeitang by gavage and those in the normal control group and model control group were administrated with deionized water at 0.01 mL·g^-1. The body mass， anal temperature， four examination information （claw and nail appearance）， basic tear secretion test， tear film rupture time， corneal fluorescein staining， and lacrimal gland HE staining were compared among groups. Compound Yangyin Qingfeitang granules were used to measure the syndrome to verify the success of modeling. ResultsAfter 28 days of continuous modeling， compared with the normal control group， the model group exhibited listless and emaciated status， coughing， drowsiness， dry and dull hair， dry and hard stool， reduced food intake and water intake， red lip circumference， red tongue with reduced fluid， dry nose and teeth， red claws and nails， body mass gain， decreased anal mild tear secretion （P<0.05）， and shortened tear film rupture time （P<0.05）. After 28 days of modeling， the mice showed large corneal fluorescein staining range， severe corneal injury， and increased content of interleukin （IL）-18， IL-β， and tumor necrosis factor （TNF）-α in lacrimal gland， compared with those in the normal control group （P<0.05）. After the treatment with Yangyin Qingfeitang， the mice had good drinking and eating conditions， with lighter redness of the tongue， moist nose， moist and shiny teeth， and the claw and nail color close to that in the normal group. Compared with the model control group， Yangyin Qingfeitang groups showed increases in body mass and anal temperature （P<0.05）， tear secretion （P<0.05）， and tear film rupture time （P<0.05）， narrowed range of corneal fluorescein staining， and declined levels of IL-18， IL-β， and TNF-α in lacrimal glands （P<0.01）. The high-dose group had the best effect， with the indicators close to the levels in the normal control group. ConclusionThe animal model of dry eye with lung Yin deficiency syndrome can be established by culture in a controlled drying system， treatment with benzalkonium chloride eye drops for 28 days， and administration of thyroxine tablet solution combined with SO₂ fumigation for 14 days.

ObjectiveTo investigate the mechanisms of Runmu Dihuang decoction （RMDHD） in treating perimenopausal dry eye with liver-kidney Yin deficiency syndrome based on the silent information regulator 3 （SIRT3）/hypoxia-inducible factor-1α （HIF-1α）/nuclear factor-κB （NF-κB） signaling pathway. MethodsSixty female Sprague-Dawley rats were randomly divided into six groups （n=10 per group）： Sham operation group， model group， sodium hyaluronate eye drop group， and low-， medium-， and high-dose RMDHD groups （5.625， 11.25， 22.50 g·kg^-1）. Except for the sham operation group， all rats underwent bilateral ovariectomy and were administered 0.1% benzalkonium chloride eye drops combined with long-term chronic irritation to establish a perimenopausal dry eye model with liver-kidney Yin deficiency syndrome. Drug administration began in the 11th week after modeling and continued for 21 days. General conditions， screen-grip test scores， tear secretion volume， tear film breakup time （TFBUT）， and corneal fluorescein staining were recorded. Serum levels of reactive oxygen species （ROS）， follicle-stimulating hormone （FSH）， estradiol （E₂）， and progesterone （PROG） were measured by enzyme-linked immunosorbent assay （ELISA）. Pathological changes in the lacrimal glands， corneas， and uteri were observed using hematoxylin-eosin （HE） staining. Protein expression levels of SIRT3， HIF-1α， phosphorylated NF-κB p65 （p-NF-κB p65）， and total NF-κB p65 in the lacrimal glands were detected by Western blot. The expression of inflammatory cytokines interleukin-1β （IL-1β） and tumor necrosis factor-α （TNF-α） in the lacrimal glands was assessed by immunohistochemistry （IHC）. ResultsAfter model establishment， no significant differences were observed among the groups except the sham operation group. Compared with the sham operation group， the other groups exhibited slowed movement， dull responses， increased irritability， reduced body weight， elevated rectal temperature， decreased screen-grip test scores， reduced tear secretion， and significantly shortened TFBUT （P<0.05）. After treatment， compared with the model group， the sodium hyaluronate eye drop group and all RMDHD groups showed improved general conditions， significantly increased tear secretion （P<0.05）， prolonged TFBUT （P<0.05）， and elevated screen-grip test scores （P<0.05）. Serum ROS and FSH levels were significantly decreased， while E₂ and PROG levels were significantly increased （P<0.05）. Pathological damage to the cornea， lacrimal glands， and uterus was ameliorated. In addition， protein expression levels of SIRT3 and HIF-1α in the lacrimal glands were significantly upregulated （P<0.05）， whereas the expression of p-NF-κB p65， IL-1β， and TNF-α was significantly downregulated （P<0.05）. ConclusionRMDHD increases tear secretion and TFBUT， improves lacrimal gland and corneal injury， and alleviates dry eye symptoms in a perimenopausal dry eye rat model with liver-kidney Yin deficiency syndrome. The underlying mechanism may be related to regulation of the SIRT3/HIF-1α/NF-κB signaling pathway， inhibition of oxidative stress and inflammatory responses， and reduction of ocular surface tissue damage.

ObjectiveThis paper aims to investigate the effects and mechanism of Mimenghua prescription in modulating the mitogen-activated protein kinase kinase （MEK）/rat sarcoma viral oncogene homolog （Ras）/rapidly accelerated fibrosarcoma kinase （Raf）/extracellular signal-regulated kinase （ERK） signaling pathway to inhibit inflammatory responses in a dry eye animal model. MethodsA total of 60 C57BL/6J mice （eight weeks old， half male and half female） were used in the experiment. Ten mice were randomly selected as the blank control group， while the remaining 50 were exposed to a controlled dry system and received instillation of 0.2% benzalkonium chloride （BAC） into the eyes for four weeks to establish a dry eye mouse model. After successful modeling， the mice were randomly divided into five groups： Model group， sodium hyaluronate group， and Mimenghua prescription groups with low dose （4.83 g·kg^-1）， medium dose （9.67 g·kg^-1）， and high dose （19.34 g·kg^-1）. The mice in the model group received an equal volume of normal saline via gavage for four weeks. The mice in the sodium hyaluronate group received instillation of sodium hyaluronate eye drops twice daily for 14 consecutive days. The tear secretion volume， tear film break-up time （TBUT）， and corneal fluorescein staining were evaluated once every two weeks. After four weeks of administration， mice were euthanized， and their lacrimal gland tissues and corneas were harvested. Hematoxylin-eosin （HE） staining was used to assess histopathological morphology. Western blot was performed to detect the protein expression levels of MEK， Ras， Raf， and ERK. Enzyme-linked immunosorbent assay （ELISA） was used to measure the contents and expressions of MEK， Ras， Raf， ERK， and interleukin （IL）-1β in lacrimal gland and corneal tissues of the mice in each group. Quantitative real-time polymerase chain reaction （Real-time PCR） was employed to determine mRNA expression levels of MEK， Ras， Raf， and ERK. ResultsThe Mimenghua prescription groups and the sodium hyaluronate group exhibited significantly increased tear secretion volume （P<0.05） and prolonged TBUT （P<0.05） after treatment. Ocular surface damage of mice was visibly recovered. Western blot results indicated that protein expression levels of MEK， Ras， Raf， and ERK in the lacrimal gland and corneal tissues were significantly downregulated in the sodium hyaluronate group and Mimenghua prescription group with high dose （P<0.05）. ELISA results showed that IL-1β levels were highest in the model group but significantly reduced in the sodium hyaluronate group and Mimenghua prescription groups （P<0.05）. Both ELISA and Real-time PCR results demonstrated that the expression levels of MEK， Ras， Raf， and ERK in the lacrimal glands and corneal tissues were significantly elevated in the model group （P<0.05）， but markedly downregulated in the sodium hyaluronate group and Mimenghua prescription groups （P<0.05）， suggesting that Mimenghua prescription can decrease the expressions of MEK， Ras， Raf， and ERK in the lacrimal glands and corneal tissues. ConclusionMimenghua prescription can reduce inflammatory responses， increase tear secretion， prolong TBUT， and promote corneal recovery by inhibiting the MEK， Ras， Raf， and ERK signaling pathways in lacrimal gland and corneal tissues.

Since its emergence in the 1980s, the human immunodeficiency virus (HIV) has caused a global pandemic, posing a severe threat to human life and health as well as social development. Although pre-exposure prophylaxis (PrEP) effectively curbs HIV transmission and antiretroviral therapy (ART) significantly extends the lifespan of patients, vaccines remain a pivotal tool for blocking transmission and ending the pandemic. The high genetic variability of HIV-1, the glycan shield of its envelope glycoproteins, and the long-term persistence of latent reservoirs have repeatedly led to bottlenecks in traditional vaccine strategies. In recent years, mRNA technology has offered a novel approach to addressing these challenges, leveraging advantages such as sequence programmability, short production cycles, native conformational expression of antigens, and self-adjuvant effects. In recent years, mRNA vaccine technology has emerged as a transformative solution to longstanding vaccinology challenges, characterized by its sequence programmability, rapid production cycles, native conformational antigen expression, and intrinsic self-adjuvanting properties. Unlike traditional platforms reliant on pathogen culture or recombinant proteins, mRNA vaccines can be expeditiously designed and updated based solely on viral genomic sequences. Lipid nanoparticle (LNP)-encapsulated mRNA facilitates endogenous antigen expression and presentation, simultaneously eliciting potent humoral and cellular immune responses. Within this landscape, self-amplifying mRNA (saRNA) further extends in vivo antigen expression to enhance the persistence of immune responses. Moreover, the LNP delivery system not only protects mRNA from degradation and mediates endosomal escape but also synergizes with mRNA to optimize immune activation via self-adjuvant effects. Importantly, mRNA platforms circumvent the pre-existing immunity associated with viral vectors and the genomic integration risks of DNA vaccines, positioning them as a cornerstone for global pandemic preparedness. This review systematically delineates recent advances in mRNA technology for HIV-1 vaccine development, focusing on four pivotal research frontiers. First, mRNA innovations building upon the RV144 trial optimize antigens through codon modification and multivalent designs to induce more durable and broad-spectrum immunity. Second, particulate mRNA vaccine strategies, utilizing virus-like particles (VLPs) and ferritin nanoparticles, achieve in situ antigen self-assembly, significantly enhancing B cell activation and reducing infection risks in non-human primate models. Third, germline-targeting mRNA vaccines address the low-affinity barrier of broadly neutralizing antibody (bNAp) precursors, efficiently activating rare precursor B cells and promoting affinity maturation. Fourth, therapeutic mRNA vaccines offer unique advantages for an HIV functional cure; combining immunogens with mRNA-encoded adjuvants potentiates cellular immunity, while LNP-mediated “shock-and-kill” strategies specifically activate latent reservoirs to guide immune clearance. Comparative analyses with traditional platforms reveal that mRNA technology redefines antigen production and presentation, simulating chronic infection through sustained expression and enabling dual-pathway presentation via endogenous synthesis. Furthermore, we explore the mechanistic innovations of mRNA vaccines in inducing bNAps: sustained in vivo production prolongs the activation window for precursor B cells and maintains germinal center (GC) reactions; endogenously expressed antigens adopt native conformations to expose conserved epitopes; and self-adjuvanting effects modulate the functions of antigen-presenting cells (APCs) and follicular helper T cells (Tfh), driving somatic hypermutation and affinity maturation. We also address critical clinical translation challenges, including immune durability, adaptability to special populations, and large-scale LNP manufacturing, while proposing targeted optimization strategies. In conclusion, this review establishes a theoretical framework for utilizing mRNA technology to overcome HIV-1 immune escape, transitioning from a descriptive paradigm to a problem-solving-based synthesis of evidence. By integrating preclinical and early clinical data, we bridge the gap between basic design and translational verification. mRNA technology is poised to become a central pillar inHIV-1 prevention and therapy, providing a robust toolset to achieve the global goal of ending the AIDS pandemic and offering a blueprint for vaccine development against other recalcitrant infectious diseases.

ObjectiveTo investigate whether Bushen Huoxue prescription improves embryo implantation through regulating exosomal miRNA to enhance maternal-fetal interface communication based on Bushen Huoxue therapy. MethodsIn the animal experiment， all the rats （except for the blank group） were administered hydroxyurea （450 mg·kg^-1） via gavage for 10 d， as well as epinephrine （0.3 mg·kg^-1） and mifepristone （5.5 mg·kg^-1） via subcutaneous injection for 7 d to establish an implantation disorder model of kidney deficiency and blood stasis type. The Bushen Huoxue prescription （BSHX） groups were administered the prescription at different doses （7.30 g·kg^-1 for the high-dose group， 3.65 g·kg^-1 for the medium-dose group， and 1.83 g·kg^-1 for the low-dose group） via gavage. The dydrogesterone group was administered the corresponding medicine （2.63 mg·kg^-1） via gavage. After intervention for 10 days， uterine histopathological changes were observed via hematoxylin-eosin （HE） staining. Mucin （MUC1）， forkhead box protein O1 （FoxO1）， and homeobox A10 （HoxA10） expression levels were detected by Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） and Western blot. Cell experiment selected primary endometrial epithelial cells （EEC） and trophoblast cells （TC） as research subjects. Exosome-free medicated serum was prepared by ultracentrifugation and cultured in complete medium. Exosomes were isolated from cell supernatants by ultracentrifugation for cross-co-culture. After 48 h， migration and invasion abilities were assessed by scratch and Transwell assays. Sequencing was then performed on EEC-origin exosomal miRNA. ResultsThe model rats exhibited thin endometrium， along with reduced blood vessels， glandules， and pinopode numbers. BSHX improved endometrial morphology and increased pinopode numbers. MUC1， FoxO1， and HoxA10 expressions were downregulated in the model rats， while these parameters were upregulated after BSHX medium- and high-dose intervention. In the cell experiment， after exosome-free medicated serum intervention for 24 h， migration and invasion abilities were enhanced in the BSHX groups （P<0.01）. In EEC-origin exosomal miRNA sequencing， gene ontology （GO） and Kyoto Encyclopedia of Genes and Genomes （KEGG） analyses revealed enrichment in biological processes （gastrulation， neuronal differentiation， alongside cell development and regeneration）， involving the mitogen-activated protein kinase （MAPK）， FoxO1， Wnt， mammalian target of rapamycin （mTOR）， and tumor necrosis factor （TNF） signaling pathways. ConclusionBSHX promotes embryo implantation by improving endometrial receptivity via regulating exosomal miRNA. These findings provide potential targets for exosomal miRNA-based assisted reproductive strategies and a novel theoretical basis for infertility treatment by traditional Chinese medicine.

ObjectiveTo explore the target of Erzhiwan in reducing myocardial injury in ovariectomized mice through non-targeted myocardial metabolomics combined with experimental verification. MethodsOvariectomized mouse model was selected， 40 female C57BL/6 mice were randomly divided into sham operation group， model group， estrogen group（estradiol valerate， 1.3×10^-4 g·kg^-1）， Erzhiwan low and high dose groups（3.12， 9.36 g·kg^-1）， with 8 mice in each group. Each administration group was given the corresponding dose of Erzhiwan by gavage， and the sham operation group and model group were given equal volume of distilled water by gavage for 12 weeks. Echocardiography was used to detect cardiac function， hematoxylin-eosin（HE） staining was used to observe myocardial morphological changes， and enzyme-linked immunosorbent assay（ELISA） was used to detect the levels of estrogen， N-terminal pro-brain natriuretic peptide（NT-proBNP）， hypersensitive troponin T（hs-TnT）， total cholesterol（TC）， triglyceride（TG）， low density lipoprotein cholesterol（LDL-C）， high density lipoprotein cholesterol（HDL-C）， interleukin（IL）-1β， IL-18 and tumor necrosis factor-α（TNF-α）. The non-targeted metabolomics of mouse myocardium were analyzed by ultra performance liquid chromatography-quadrupole-electrostatic field orbital trap high-resolution mass spectrometry（UPLC-Q-Exactive Orbitrap MS）， and the differential metabolites and corresponding metabolic pathways were obtained. The mRNA expression levels of phosphatidylinositol 3-kinase（PI3K） and protein kinase B（Akt） in mouse myocardial tissues were detected by real-time fluorescence quantitative polymerase chain reaction（Real-time PCR）， and the protein expression levels of PI3K， Akt， phosphorylated（p）-Akt were detected by Western blot. ResultsCompared with the sham operation group， the model group showed abnormal cardiac function， increased myocardial fiber space， cardiomyocyte atrophy， sarcoplasmic aggregation， and occasional dissolution or rupture of muscle fiber， the level of estrogen in the serum was decreased， the levels of NT-proBNP， hs-TnT， IL-1β， IL-18， TNF-α， TG， TC and LDL-C were increased， and the level of HDL-C was decreased（P<0.01）. Compared with the model group， Erzhiwan could increase the level of estrogen， improve the abnormal cardiac function， reduce the pathological injury of myocardial tissue， decrease the levels of myocardial injury markers（NT-proBNP， hs-TnT） and inflammatory factors（IL-1β， IL-18， TNF-α）， decrease the levels of TG， TC， LDL-C， and increased the level of HDL-C（P<0.01）. The results of non-targeted myocardial metabolomics showed that 31 of the 162 differential metabolites between the model group and sham operation group were significantly adjusted after administration of Erzhiwan， which were mainly glycerol phospholipid metabolites. Pathway enrichment results showed that Erzhiwan mainly affected glycerophospholipid metabolic pathway， PI3K-Akt pathway， cyclic guanosine monophosphate（cGMP）-protein kinase G（PKG） pathway and other metabolic pathways. Compared with the sham operation group， the levels of phosphatidylcholine（PC， 11 types） and phosphatidylethanolamine（PE， 5 types） in mouse myocardial tissue of the model group were increased（P<0.05， P<0.01）， and the mRNA and protein expressions of PI3K and p-Akt were decreased（P<0.05， P<0.01）. Compared with the model group， the levels of PC（11 types） and PE（5 types） were decreased（P<0.05， P<0.01） in myocardial tissue of Erzhiwan group， the mRNA and protein expressions of PI3K and p-Akt were elevated（P<0.01）. ConclusionErzhiwan can alleviate the pathological injury of myocardium in ovariectomized mice， improve the abnormal cardiac function， improve lipid metabolism disorder， and reduce the levels of myocardial injury markers and inflammatory factors， which involves a number of signaling and metabolic pathways in the heart， among which glycerophospholipid metabolism pathway and PI3K/Akt pathway may have key roles.

Objective To investigate whether aberrant DNA methylation of ubiquinol-cytochrome C reductase core protein 1(UQCRC1)is related to cognitive impairment caused by neonatal sevoflurane exposure.Methods A total of 94 SPF C57 mice of either sex,aged 6 d,and weighing 4～6 g,were randomly divided into 7 groups:control group(Con,n=6),sevoflurane-6 and-24 h exposure groups(Sev-6 and-24 h,n=6),control+DMSO group(Con+DMSO,n=19),control+5-aza-2'-deoxycytidine(5-AZA,methylation inhibitor)group(Con+5-AZA,n=19),sevoflurane+DMSO group(Sev+DMSO group,n=19),and sevoflurane+5-AZA group(Sev+5-AZA group,n=19).From 6 to 8 d after birth,the mice of the Sev-6 and-24 h exposure groups were exposed to 3％sevoflurane daily(with 97％oxygen,2 L/min,2 h per day),while those from the Con groups were given exposure of 100％oxygen(2 L/min,2 h per day).For the mice of the 5-AZA and DMSO groups,1 mg/kg of 5-AZA or an equal volume of DMSO was injected intraperitoneally 30 min before daily exposure.In 6 and 24 h after the last exposure to sevoflurane,6 mice from the Con,Sev-6 h,and Sev-24 h groups were euthanized for biochemical analysis,and in 24 h post-exposure,6 mice from the Con+DMSO,Con+5-AZA,Sev+DMSO,and Sev+5-AZA groups were randomly selected for biochemical analysis,while another 3 mice from above each group were also randomly selected for morphological analysis.The remaining 10 mice in these groups underwent behavioral testing(open field test,novel object test,and Y-maze test)at 30～33 d after birth to assess cognitive function,and were euthanized in 24 h after the final behavioral test.RT-qPCR and Western blotting were used to detect the hippocampal expression of UQCRC1,DNA methyltransferases(Dnmts),and methyl CpG binding protein 2(Mecp2)at mRNA and protein levels,respectively.Immunofluorescence assay was employed to observe the distribution and expression of UQCRC1 in the hippocampus.Bisulfite sequencing PCR(BSP)was applied to measure the methylation in the UQCRC1 promoter region.Results Compared with the Con group,the mRNA and protein levels of UQCRC1 were down-regulated(P<0.05),and the mRNA level of Dnmts was up-regulated(P<0.05)in both the Sev-6 h and Sev-24 h exposure groups,while the methylation level in the UQCRC1 promoter region was enhanced in the Sev-24 h exposure group(P<0.05).Additionally,the Sev+5-AZA group had obviously increased mRNA and protein levels of UQCRC1(P<0.05),and notable improvement in cognitive impairment(P<0.05)when compared with the Sev+DMSO group.Conclusion Hypermethylation of UQCRC1 promoter region and thus down-regulating its mRNA and protein expression might be the main mechanism by which repeated neonatal sevoflurane exposure induces cognitive impairment later in life.