1.Structure and Function of GPR126/ADGRG6
Ting-Ting WU ; Si-Qi JIA ; Shu-Zhu CAO ; De-Xin ZHU ; Guo-Chao TANG ; Zhi-Hua SUN ; Xing-Mei DENG ; Hui ZHANG
Progress in Biochemistry and Biophysics 2025;52(2):299-309
GPR126, also known as ADGRG6, is one of the most deeply studied aGPCRs. Initially, GPR126 was thought to be a receptor associated with muscle development and was primarily expressed in the muscular and skeletal systems. With the deepening of research, it was found that GPR126 is expressed in multiple mammalian tissues and organs, and is involved in many biological processes such as embryonic development, nervous system development, and extracellular matrix interactions. Compared with other aGPCRs proteins, GPR126 has a longer N-terminal domain, which can bind to ligands one-to-one and one-to-many. Its N-terminus contains five domains, a CUB (complement C1r/C1s, Uegf, Bmp1) domain, a PTX (Pentraxin) domain, a SEA (Sperm protein, Enterokinase, and Agrin) domain, a hormone binding (HormR) domain, and a conserved GAIN domain. The GAIN domain has a self-shearing function, which is essential for the maturation, stability, transport and function of aGPCRs. Different SEA domains constitute different GPR126 isomers, which can regulate the activation and closure of downstream signaling pathways through conformational changes. GPR126 has a typical aGPCRs seven-transmembrane helical structure, which can be coupled to Gs and Gi, causing cAMP to up- or down-regulation, mediating transmembrane signaling and participating in the regulation of cell proliferation, differentiation and migration. GPR126 is activated in a tethered-stalk peptide agonism or orthosteric agonism, which is mainly manifested by self-proteolysis or conformational changes in the GAIN domain, which mediates the rapid activation or closure of downstream pathways by tethered agonists. In addition to the tethered short stem peptide activation mode, GPR126 also has another allosteric agonism or tunable agonism mode, which is specifically expressed as the GAIN domain does not have self-shearing function in the physiological state, NTF and CTF always maintain the binding state, and the NTF binds to the ligand to cause conformational changes of the receptor, which somehow transmits signals to the GAIN domain in a spatial structure. The GAIN domain can cause the 7TM domain to produce an activated or inhibited signal for signal transduction, For example, type IV collagen interacts with the CUB and PTX domains of GPR126 to activate GPR126 downstream signal transduction. GPR126 has homology of 51.6%-86.9% among different species, with 10 conserved regions between different species, which can be traced back to the oldest metazoans as well as unicellular animals.In terms of diseases, GPR126 dysfunction involves the pathological process of bone, myelin, embryo and other related diseases, and is also closely related to the occurrence and development of malignant tumors such as breast cancer and colon cancer. However, the biological function of GPR126 in various diseases and its potential as a therapeutic target still needs further research. This paper focuses on the structure, interspecies differences and conservatism, signal transduction and biological functions of GPR126, which provides ideas and references for future research on GPR126.
2.Effect of Chaihu Jia Longgu Muli Decoction on apoptosis in rats with heart failure after myocardial infarction through IκBα/NF-κB pathway.
Miao-Yu SONG ; Cui-Ling ZHU ; Yi-Zhuo LI ; Xing-Yuan LI ; Gang LIU ; Xiao-Hui LI ; Yan-Qin SUN ; Ming-Yuan DU ; Lei JIANG ; Chao-Chong YUE
China Journal of Chinese Materia Medica 2025;50(8):2184-2192
This study aims to explore the protective effect of Chaihu Jia Longgu Muli Decoction on rats with heart failure after myocardial infarction, and to clarify its possible mechanisms, providing a new basis for basic research on the mechanism of classic Chinese medicinal formula-mediated inflammatory response in preventing and treating heart failure induced by apoptosis after myocardial infarction. A heart failure model after myocardial infarction was established in rats by coronary artery ligation. The rats were divided into sham group, model group, and low, medium, and high-dose groups of Chaihu Jia Longgu Muli Decoction, with 10 rats in each group. The low-dose, medium-dose, and high-dose groups of Chaihu Jia Longgu Muli Decoction were given 6.3, 12.6, and 25.2 g·kg~(-1) doses by gavage, respectively. The sham group and model group were given an equal volume of distilled water by gavage once daily for four consecutive weeks. Cardiac function was assessed using color Doppler echocardiography. Myocardial pathology was detected by hematoxylin-eosin(HE) staining, apoptosis was measured by TUNEL assay, and mitophagy was observed by transmission electron microscopy. The levels of tumor necrosis factor-α(TNF-α), interleukin(IL)-1β, and N-terminal pro-B-type natriuretic peptide(NT-proBNP) in serum were detected by enzyme-linked immunosorbent assay(ELISA). The expression of apoptosis-related proteins B-cell lymphoma 2(Bcl-2), Bcl-2-associated X protein(Bax), and cleaved caspase-3 was detected by Western blot. Additionally, the expression of phosphorylated nuclear transcription factor-κB(NF-κB) p65(p-NF-κB p65)(upstream) and nuclear factor kappa B inhibitor alpha(IκBα)(downstream) in the NF-κB signaling pathway was assessed by Western blot. The results showed that compared with the sham group, left ventricular ejection fraction(LVEF) and left ventricular short axis shortening(LVFS) in the model group were significantly reduced, while left ventricular end diastolic diameter(LVEDD) and left ventricular end systolic diameter(LVESD) increased significantly. Myocardial tissue damage was severe, with widened intercellular spaces and disorganized cell arrangement. The apoptosis rate was increased, and mitochondria were enlarged with increased vacuoles. Levels of TNF-α, IL-1β, and NT-proBNP were elevated, indicating an obvious inflammatory response. The expression of pro-apoptotic factors Bax and cleaved caspase-3 increased, while the anti-apoptotic factor Bcl-2 decreased. The expression of p-NF-κB p65 was upregulated, and the expression of IκBα was downregulated. In contrast, the Chaihu Jia Longgu Muli Decoction groups showed significantly improved of LVEF, LVFS and decreased LVEDD, LVESD compared to the model group. Myocardial tissue damage was alleviated, and intercellular spaces were reduced. The apoptosis rate decreased, mitochondrial volume decreased, and the levels of TNF-α, IL-1β, and NT-proBNP were lower. The expression of pro-apoptotic factors Bax and cleaved caspase-3 decreased, while the expression of the anti-apoptotic factor Bcl-2 increased. Additionally, the expression of p-NF-κB p65 decreased, while IκBα expression increased. In summary, this experimental study shows that Chaihu Jia Longgu Muli Decoction can reduce the inflammatory response and apoptosis rate in rats with heart failure after myocardial infarction, which may be related to the regulation of the IκBα/NF-κB signaling pathway.
Animals
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Apoptosis/drug effects*
;
Drugs, Chinese Herbal/administration & dosage*
;
Rats
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Myocardial Infarction/physiopathology*
;
Male
;
NF-kappa B/genetics*
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Heart Failure/etiology*
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Rats, Sprague-Dawley
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Signal Transduction/drug effects*
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NF-KappaB Inhibitor alpha/genetics*
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Humans
;
Tumor Necrosis Factor-alpha/genetics*
3.Specific effect of inserted sham acupuncture and its impact on the estimation of acupuncture treatment effect in randomized controlled trials: A systematic survey.
Xiao-Chao LUO ; Jia-Li LIU ; Ming-Hong YAO ; Ye-Meng CHEN ; Arthur Yin FAN ; Fan-Rong LIANG ; Ji-Ping ZHAO ; Ling ZHAO ; Xu ZHOU ; Xiao-Ying ZHONG ; Jia-Hui YANG ; Bo LI ; Ying ZHANG ; Xin SUN ; Ling LI
Journal of Integrative Medicine 2025;23(6):630-640
BACKGROUND:
The use of inserted sham acupuncture as a placebo in randomized controlled trials (RCTs) is controversial, because it may produce specific effects that cause an underestimation of the effect of acupuncture treatment.
OBJECTIVE:
This systematic survey investigates the magnitude of insert-specific effects of sham acupuncture and whether they affect the estimation of acupuncture treatment effects.
SEARCH STRATEGY:
PubMed, Embase and Cochrane Central Register of Controlled Trials were searched to identify acupuncture RCTs from their inception until December 2022.
INCLUSION CRITERIA:
RCTs that evaluated the effects of acupuncture compared to sham acupuncture and no treatment.
DATA EXTRACTION AND ANALYSIS:
The total effect measured for an acupuncture treatment group in RCTs were divided into three components, including the natural history and/or regression to the mean effect (controlled for no-treatment group), the placebo effect, and the specific effect of acupuncture. The first two constituted the contextual effect of acupuncture, which is mimicked by a sham acupuncture treatment group. The proportion of acupuncture total effect size was considered to be 1. The proportion of natural history and/or regression to the mean effect (PNE) and proportional contextual effect (PCE) of included RCTs were pooled using meta-analyses with a random-effect model. The proportion of acupuncture placebo effect was the difference between PCE and PNE in RCTs with non-inserted sham acupuncture. The proportion of insert-specific effect of sham acupuncture (PIES) was obtained by subtracting the proportion of acupuncture placebo effect and PNE from PCE in RCTs with inserted sham acupuncture. The impact of PIES on the estimation of acupuncture's treatment effect was evaluated by quantifying the percentage of RCTs that the effect of outcome changed from no statistical difference to statistical difference after removing PIES in the included studies, and the impact of PIES was externally validated in other acupuncture RCTs with an inserted sham acupuncture group that were not used to calculate PIES.
RESULTS:
This analysis included 32 studies with 5492 patients. The overall PNE was 0.335 (95% confidence interval [CI], 0.255-0.415) and the PCE of acupuncture was 0.639 (95% CI, 0.567-0.710) of acupuncture's total effect. The proportional contribution of the placebo effect to acupuncture's total effect was 0.191, and the PIES was 0.189. When we modeled the exclusion of the insert-specific effect of sham acupuncture, the acupuncture treatment effect changed from no difference to a significant difference in 45.45% of the included RCTs, and in 40.91% of the external validated RCTs.
CONCLUSION
The insert-specific effect of sham acupuncture in RCTs represents 18.90% of acupuncture's total effect and significantly affects the evaluation of the acupuncture treatment effect. More than 40% of RCTs that used inserted sham acupuncture would draw different conclusions if the PIES had been controlled for. Considering the impact of the insert-specific effect of sham acupuncture, caution should be taken when using inserted sham acupuncture placebos in RCTs. Please cite this article as: Luo XC, Liu JL, Yao MH, Chen YM, Fan AY, Liang FR, Zhao JP, Zhao L, Zhou X, Zhong XY, Yang JH, Li B, Zhang Y, Sun X, Li L. Specific effect of inserted sham acupuncture and its impact on the estimation of acupuncture treatment effect in randomized controlled trials: A systematic survey. J Integr Med. 2025; 23(6):630-640.
Acupuncture Therapy/methods*
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Humans
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Randomized Controlled Trials as Topic
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Placebo Effect
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Placebos
;
Treatment Outcome
4.Efficacy and safety of recombinant human anti-SARS-CoV-2 monoclonal antibody injection(F61 injection)in the treatment of patients with COVID-19 combined with renal damage:a randomized controlled exploratory clinical study
Ding-Hua CHEN ; Chao-Fan LI ; Yue NIU ; Li ZHANG ; Yong WANG ; Zhe FENG ; Han-Yu ZHU ; Jian-Hui ZHOU ; Zhe-Yi DONG ; Shu-Wei DUAN ; Hong WANG ; Meng-Jie HUANG ; Yuan-Da WANG ; Shuo-Yuan CONG ; Sai PAN ; Jing ZHOU ; Xue-Feng SUN ; Guang-Yan CAI ; Ping LI ; Xiang-Mei CHEN
Chinese Journal of Infection Control 2024;23(3):257-264
Objective To explore the efficacy and safety of recombinant human anti-severe acute respiratory syn-drome coronavirus 2(anti-SARS-CoV-2)monoclonal antibody injection(F61 injection)in the treatment of patients with coronavirus disease 2019(COVID-19)combined with renal damage.Methods Patients with COVID-19 and renal damage who visited the PLA General Hospital from January to February 2023 were selected.Subjects were randomly divided into two groups.Control group was treated with conventional anti-COVID-19 therapy,while trial group was treated with conventional anti-COVID-19 therapy combined with F61 injection.A 15-day follow-up was conducted after drug administration.Clinical symptoms,laboratory tests,electrocardiogram,and chest CT of pa-tients were performed to analyze the efficacy and safety of F61 injection.Results Twelve subjects(7 in trial group and 5 in control group)were included in study.Neither group had any clinical progression or death cases.The ave-rage time for negative conversion of nucleic acid of SARS-CoV-2 in control group and trial group were 3.2 days and 1.57 days(P=0.046),respectively.The scores of COVID-19 related target symptom in the trial group on the 3rd and 5th day after medication were both lower than those of the control group(both P<0.05).According to the clinical staging and World Health Organization 10-point graded disease progression scale,both groups of subjects improved but didn't show statistical differences(P>0.05).For safety,trial group didn't present any infusion-re-lated adverse event.Subjects in both groups demonstrated varying degrees of elevated blood glucose,elevated urine glucose,elevated urobilinogen,positive urine casts,and cardiac arrhythmia,but the differences were not statistica-lly significant(all P>0.05).Conclusion F61 injection has initially demonstrated safety and clinical benefit in trea-ting patients with COVID-19 combined with renal damage.As the domestically produced drug,it has good clinical accessibility and may provide more options for clinical practice.
5.Clinical safety and validity analysis of retrograde new endo-scopic visual field in miniature pigs
Zhe KUANG ; Peng LI ; Da-Qing JIN ; Yong-Chao ZHANG ; Hui-Li GUO ; Yu-Fei ZHANG ; Guang-Lin HE ; Guo-Feng SUN ; Yuan HE
Chinese Journal of Current Advances in General Surgery 2024;27(1):14-18
Objective:To study the clinical safety and validity of retrograde new endoscopic field of vision in miniature pigs.Methods:6 live miniature pigs were selected as study subjects,En-doscopic Retrograde New View(ERNV)was selected.The performance,image quality and intraoper-ative and postoperative complications were evaluated.To evaluate whether all the experimental ani-mals could complete the relevant endoscopy.Verify ERNV's operating performance,including whether the duodenoscope can enter the biliary tract smoothly,and made sure whether the injection,suction,and instrument channels were unobstructed.Choledochoscope image clarity,color resolu-tion,image deformation and distortion,accurate evaluation of lumen conditions and clear observation of mucosal surface conditions were analyzed.Whether there were operant injuries such as bleeding and perforation,as well as adverse events such as respiratory depression and cardiac arrest.The sur-vival status and adverse reactions of all pigs were observed.Results:The choledochoscope was successfully inserted into the bile duct of 6 miniature pigs.The product had good operation perfor-mance and could enter the bile duct through the duodenoscope smoothly.The injection,suction and instrument channels were relatively smooth.In addition,the endoscopic images are clear,with better color resolution,and without image deformation and distortion,which can realize accurate evaluation of the conditions in the lumen and observe the mucosal surface conditions more clearly.No bile duct stenosis or dilatation occurred in all miniature pigs,and the bile duct mucosa was smooth,without hyperemia and edema,and no abnormal thickening or bending of mucous vessels.During the exami-nation,there were no operational injuries such as bleeding and perforation,and no adverse events such as respiratory depression and cardiac arrest occurred.The vital signs of all miniature pigs tended to be stable after operation,and the survival state was good,and there were no complications such as cholangitis,bleeding and perforation.Conclusion:ERNV has good clinical safety and efficacy,ex-cellent operation performance and excellent image quality,and is worthy of clinical application.
6.Research progress in the application of ivabradine in children with cardiovascular diseases
Chinese Journal of Contemporary Pediatrics 2024;26(7):782-788
Ivabradine,as a specific If current inhibitor,has been widely used in the treatment of chronic heart failure in adults due to its ability to reduce heart rate without affecting myocardial contractility and blood pressure.It has also shown good effects in various types of tachyarrhythmias.However,the application of ivabradine in pediatric cardiovascular diseases still faces many limitations.This article reviews the current research progress on the use of ivabradine in treating pediatric cardiovascular diseases both domestically and internationally,aiming to provide guidance for pediatric cardiologists.
7.Development and validation of a dynamic prediction tool for post-endo-scopic retrograde cholangiopancreatography early biliary tract infection in patients with choledocholithiasis
Peng LI ; Chao LIANG ; Jia-Feng YAN ; Chun-Hui GAO ; Zhi-Jie MA ; Zhan-Tao XIE ; Ming-Jie SUN
Chinese Journal of Infection Control 2024;23(6):692-699
Objective To develop a prediction tool for post-endoscopic retrograde cholangiopancreatography(ER-CP)early biliary tract infection(PEEBI)in patients with choledocholithiasis,and assist clinical decision-making be-fore ERCP and early personalized intervention after ERCP.Methods An observational bidirectional cohort study was adopted to select inpatients with choledocholithiasis who underwent ERCP in a hospital.Directed acyclic graph(DAGs)and the least absolute shrinkage and selection operator(LASSO)were used to predict PEEBI based on lo-gistic regression,and the models were compared and validated internally and externally.Results From January 1,2020 to September 30,2023,a total of 2 121 patients with choledocholithiasis underwent ERCP were enrolled,of whom 77(3.6%)developed PEEBI,mostly in the first 2 days after surgery(66.2%).The major influencing fac-tors for PEEBI were non-iatrogenic patient-related factors,namely diabetes mellitus(OR=2.43,95%CI:1.14-4.85),bile duct malignancy(OR=3.95,95%CI:1.74-8.31)and duodenal papillary diverticulum(OR=4.39,95%CI:1.86-9.52).Compared with the LASSO model,the DAGs model showed higher ability(3.0%)in com-prehensive discrimination(P=0.007),as well as good differentiation performance(D=0.133,P=0.894)and cal-ibration performance(x2=5.499,P=0.703)in external validation.Conclusion The DAGs model constructed in this study has good predictive performance.With the help of this tool,targeted early preventive measures in clinical practice can be taken to reduce the occurrence of PEEBI.
8.Sentinel surveillance data of influenza in Hunan Province from 2014 to 2023
Xiao-Lei WANG ; Chao-Yang HUANG ; Qian-Lai SUN ; Zhi-Hong DENG ; Yi-Wei HUANG ; Shan-Lu ZHAO ; Kai-Wei LUO ; Xiang REN ; Sheng-Bao CHEN ; Zhi-Hui DAI
Chinese Journal of Infection Control 2024;23(11):1413-1420
Objective To understand the prevalence characteristics of influenza and changes of influenza virus strains,and provide reference for the prevention and control of influenza in the province.Methods Surveillance da-ta about influenza in Hunan Province from 2014 to 2023 were exported from China Influenza Surveillance Informa-tion System.Differences in the percentage of influenza-like illness(ILI)cases(percentage of influenza-like cases[ILI%]in outpatient and emergency department visits)among different years and different populations,as well as the positive rate of influenza virus in ILI specimens were compared.Results From 2014 to 2023,over 2.65 million cases of ILI were reported,with an ILI%of 4.70%.ILI%among different years presented statistically significant differences(P<0.001).People aged 0-14 years old were the main population with ILI,accounting for 82.90%.The positive rate of influenza virus in ILI specimens was 14.14%,the positive rate of influenza virus among diffe-rent years and age groups were both significantly different(both P<0.001).The main prevalent influenza strains from 2014 to 2023 included types A(H1N1),A(H3N2),B(Victoria),and B(Yamagata),alternating among di-fferent years.However,type B(Yamagata)strains were not detected from 2020 to 2023.There were basically two influenza prevalence seasons every year,namely winter-spring and summer.Conclusion People<15 years old are the main population of influenza,and the prevalence peaks are in winter-spring and summer.From 2021 to 2023,the prevalence alternates mainly among 3 types:A(H1N1),A(H3N2),and B(Victoria).
9.Clinical characteristics and risk factors for early-onset necrotizing enterocolitis in preterm infants with very/extremely low birth weight.
Zeng-Yuan YU ; Shu-Jing XU ; Hui-Qing SUN ; Ming-Chao LI ; Shan XING ; Ping CHENG ; Hong-Bo ZHANG ; Ying-Ying WANG ; Zi-Jiu YANG
Chinese Journal of Contemporary Pediatrics 2023;25(2):147-152
OBJECTIVES:
To investigate the clinical characteristics and risk factors for early-onset necrotizing enterocolitis (NEC) in preterm infants with very/extremely low birth weight (VLBW/ELBW).
METHODS:
A retrospective analysis was performed on the medical data of 194 VLBW/ELBW preterm infants with NEC who were admitted to Children's Hospital Affiliated to Zhengzhou University from January 2014 to December 2021. These infants were divided into early-onset group (onset in the first two weeks of life; n=62) and late-onset group (onset two weeks after birth; n=132) based on their onset time. The two groups were compared in terms of perinatal conditions, clinical characteristics, laboratory examination results, and clinical outcomes. Sixty-two non-NEC infants with similar gestational age and birth weight who were hospitalized at the same period as these NEC preterm infants were selected as the control group. The risk factors for the development of early-onset NEC were identified using multivariate logistic regression analysis.
RESULTS:
Compared with the late-onset group, the early-onset group had significantly higher proportions of infants with 1-minute Apgar score ≤3, stage III NEC, surgical intervention, grade ≥3 intraventricular hemorrhage, apnea, and fever or hypothermia (P<0.05). The multivariate logistic regression analysis showed that feeding intolerance, blood culture-positive early-onset sepsis, severe anemia, and hemodynamically significant patent ductus arteriosus were independent risk factors for the development of early-onset NEC in VLBW/ELBW preterm infants (P<0.05).
CONCLUSIONS
VLBW/ELBW preterm infants with early-onset NEC have more severe conditions compared with those with late-onset NEC. Neonates with feeding intolerance, blood culture-positive early-onset sepsis, severe anemia, or hemodynamically significant patent ductus arteriosus have a higher risk of early-onset NEC.
Child
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Infant
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Female
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Pregnancy
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Infant, Newborn
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Humans
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Infant, Premature
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Infant, Extremely Low Birth Weight
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Ductus Arteriosus, Patent
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Enterocolitis, Necrotizing/etiology*
;
Retrospective Studies
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Infant, Newborn, Diseases
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Infant, Premature, Diseases/etiology*
;
Risk Factors
10.Electrotaxis of alveolar epithelial cells in direct-current electric fields.
Chao-Yue YANG ; Jian-Hui SUN ; Kan ZHU ; Juan DU ; Ying ZHANG ; Cong-Hua LU ; Wen-Yi LIU ; Ke-Jun ZHANG ; An-Qiang ZHANG ; Ling ZENG ; Jian-Xin JIANG ; Li LI
Chinese Journal of Traumatology 2023;26(3):155-161
PURPOSE:
This study aims to elucidate the electrotaxis response of alveolar epithelial cells (AECs) in direct-current electric fields (EFs), explore the impact of EFs on the cell fate of AECs, and lay the foundation for future exploitation of EFs for the treatment of acute lung injury.
METHODS:
AECs were extracted from rat lung tissues using magnetic-activated cell sorting. To elucidate the electrotaxis responses of AECs, different voltages of EFs (0, 50, 100, and 200 mV/mm) were applied to two types of AECs, respectively. Cell migrations were recorded and trajectories were pooled to better demonstrate cellular activities through graphs. Cell directionality was calculated as the cosine value of the angle formed by the EF vector and cell migration. To further demonstrate the impact of EFs on the pulmonary tissue, the human bronchial epithelial cells transformed with Ad12-SV40 2B (BEAS-2B cells) were obtained and experimented under the same conditions as AECs. To determine the influence on cell fate, cells underwent electric stimulation were collected to perform Western blot analysis.
RESULTS:
The successful separation and culturing of AECs were confirmed through immunofluorescence staining. Compared with the control, AECs in EFs demonstrated a significant directionality in a voltage-dependent way. In general, type Ⅰ alveolar epithelial cells migrated faster than type Ⅱ alveolar epithelial cells, and under EFs, these two types of cells exhibited different response threshold. For type Ⅱ alveolar epithelial cells, only EFs at 200 mV/mm resulted a significant difference to the velocity, whereas for, EFs at both 100 mV/mm and 200 mV/mm gave rise to a significant difference. Western blotting suggested that EFs led to an increased expression of a AKT and myeloid leukemia 1 and a decreased expression of Bcl-2-associated X protein and Bcl-2-like protein 11.
CONCLUSION
EFs could guide and accelerate the directional migration of AECs and exert antiapoptotic effects, which indicated that EFs are important biophysical signals in the re-epithelialization of alveolar epithelium in lung injury.
Humans
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Rats
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Animals
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Alveolar Epithelial Cells
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Lung
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Lung Injury
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Cell Movement/physiology*

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