1.Polypeptide-based Nanocarriers for Oral Targeted Delivery of CAR Genes to Pancreatic Cancer
Feng XIN ; Jian REN ; Zhao-Zhen LI ; Quan FANG ; Rui-Jing LIANG ; Lan-Lan LIU ; Lin-Tao CAI
Progress in Biochemistry and Biophysics 2026;53(2):431-441
ObjectivePancreatic ductal adenocarcinoma (PDAC) exhibits a limited response to current treatments due to its dense fibrotic stroma and highly immunosuppressive tumor microenvironment. In recent years, advancements in cellular immunotherapy, particularly chimeric antigen receptor macrophage (CAR-M) therapy, have offered new hope for pancreatic cancer treatment. Although CAR-M therapy demonstrates dual potential in directly killing tumor cells and remodeling the immune microenvironment, it still faces challenges such as complex in vitro preparation processes and low in vivo targeting and delivery efficiency. Therefore, developing strategies for efficient and targeted in vivo delivery of CAR genes has become crucial for overcoming current therapeutic limitations. This study aims to develop an orally administrable nano-gene delivery system for the targeted delivery of CAR genes to pancreatic tumor sites. MethodsCore nano-gene particles (PNP/pCAR) were constructed by loading plasmid DNA encoding CAR (pCAR) with cationic polypeptides (PNP). Subsequently, PNP/pCAR was surface-modified with β-glucan to prepare the targeted nanoparticles (βGlus-PNP/pCAR). The loading efficiency of PNP for pCAR was quantitatively assessed by gel retardation assay. The particle size, Zeta potential, morphology, and storage stability of PNP/pCAR were characterized using a Malvern particle size analyzer and transmission electron microscopy. At the cellular level, RAW 264.7 macrophages were selected. The cytotoxicity of PNP/pCAR was evaluated using the CCK-8 assay. The cellular uptake efficiency and lysosomal escape ability of the nanoparticles were assessed via flow cytometry and confocal microscopy. Transfection efficiency was quantitatively evaluated by detecting the expression of the reporter gene GFP using flow cytometry. At the in vivo level, an orthotopic pancreatic cancer mouse model was established. Cy7-labeled βGlus-PNP/pCAR nanoparticles were administered orally, and the fluorescence distribution in mice was dynamically monitored at 1, 2, 4, 8, and 16 h post-administration using a small animal in vivo imaging system. Forty-eight hours after oral gavage, the mice were euthanized, and pancreatic tumor tissues were collected for further analysis of intratumoral fluorescence signals using the imaging system. Additionally, βGlus-PNP/pCAR-GFP nanoparticles loaded with the reporter gene (GFP) were administered orally. Forty-eight hours post-administration, pancreatic tumor tissues were harvested to prepare frozen sections, and GFP expression was observed and analyzed under a fluorescence microscope. ResultsThe PNP carrier exhibited a high loading capacity for pCAR. The successfully prepared PNP/pCAR nanoparticles were regular spheres with a hydrodynamic diameter of approximately (120±10) nm and a Zeta potential of about +(6±1) mV. They maintained good structural stability after incubation in PBS buffer for 7 d. Cell experiments demonstrated that PNP/pCAR exhibited no significant cytotoxicity in RAW 264.7 cells while being efficiently internalized and effectively escaping lysosomal degradation. The transfection positive rate of PNP/pCAR-GFP in RAW 264.7 cells reached (25±3)%, surpassing that of Lipofectamine 2000-loaded pCAR-GFP (Lipo/pCAR-GFP), which was (20±1)%.In vivo experiments revealed that, compared to unmodified PNP/pCAR, βGlus-PNP/pCAR exhibited strongerin situ pancreatic tumor targeting ability after oral administration. Furthermore, oral administration of βGlus-PNP/pCAR-GFP resulted in significant GFP protein expression detectable within pancreatic tumor tissues. ConclusionThis study successfully constructed and validated an orally administrable, pancreatic cancer-targeting polypeptide-based nano-gene delivery system. It provides an important technological foundation in delivery systems and experimental basis for the subsequent development of in situ CAR-M-based therapeutic strategies for pancreatic cancer.
2.Polypeptide-based Nanocarriers for Oral Targeted Delivery of CAR Genes to Pancreatic Cancer
Feng XIN ; Jian REN ; Zhao-Zhen LI ; Quan FANG ; Rui-Jing LIANG ; Lan-Lan LIU ; Lin-Tao CAI
Progress in Biochemistry and Biophysics 2026;53(2):431-441
ObjectivePancreatic ductal adenocarcinoma (PDAC) exhibits a limited response to current treatments due to its dense fibrotic stroma and highly immunosuppressive tumor microenvironment. In recent years, advancements in cellular immunotherapy, particularly chimeric antigen receptor macrophage (CAR-M) therapy, have offered new hope for pancreatic cancer treatment. Although CAR-M therapy demonstrates dual potential in directly killing tumor cells and remodeling the immune microenvironment, it still faces challenges such as complex in vitro preparation processes and low in vivo targeting and delivery efficiency. Therefore, developing strategies for efficient and targeted in vivo delivery of CAR genes has become crucial for overcoming current therapeutic limitations. This study aims to develop an orally administrable nano-gene delivery system for the targeted delivery of CAR genes to pancreatic tumor sites. MethodsCore nano-gene particles (PNP/pCAR) were constructed by loading plasmid DNA encoding CAR (pCAR) with cationic polypeptides (PNP). Subsequently, PNP/pCAR was surface-modified with β-glucan to prepare the targeted nanoparticles (βGlus-PNP/pCAR). The loading efficiency of PNP for pCAR was quantitatively assessed by gel retardation assay. The particle size, Zeta potential, morphology, and storage stability of PNP/pCAR were characterized using a Malvern particle size analyzer and transmission electron microscopy. At the cellular level, RAW 264.7 macrophages were selected. The cytotoxicity of PNP/pCAR was evaluated using the CCK-8 assay. The cellular uptake efficiency and lysosomal escape ability of the nanoparticles were assessed via flow cytometry and confocal microscopy. Transfection efficiency was quantitatively evaluated by detecting the expression of the reporter gene GFP using flow cytometry. At the in vivo level, an orthotopic pancreatic cancer mouse model was established. Cy7-labeled βGlus-PNP/pCAR nanoparticles were administered orally, and the fluorescence distribution in mice was dynamically monitored at 1, 2, 4, 8, and 16 h post-administration using a small animal in vivo imaging system. Forty-eight hours after oral gavage, the mice were euthanized, and pancreatic tumor tissues were collected for further analysis of intratumoral fluorescence signals using the imaging system. Additionally, βGlus-PNP/pCAR-GFP nanoparticles loaded with the reporter gene (GFP) were administered orally. Forty-eight hours post-administration, pancreatic tumor tissues were harvested to prepare frozen sections, and GFP expression was observed and analyzed under a fluorescence microscope. ResultsThe PNP carrier exhibited a high loading capacity for pCAR. The successfully prepared PNP/pCAR nanoparticles were regular spheres with a hydrodynamic diameter of approximately (120±10) nm and a Zeta potential of about +(6±1) mV. They maintained good structural stability after incubation in PBS buffer for 7 d. Cell experiments demonstrated that PNP/pCAR exhibited no significant cytotoxicity in RAW 264.7 cells while being efficiently internalized and effectively escaping lysosomal degradation. The transfection positive rate of PNP/pCAR-GFP in RAW 264.7 cells reached (25±3)%, surpassing that of Lipofectamine 2000-loaded pCAR-GFP (Lipo/pCAR-GFP), which was (20±1)%.In vivo experiments revealed that, compared to unmodified PNP/pCAR, βGlus-PNP/pCAR exhibited strongerin situ pancreatic tumor targeting ability after oral administration. Furthermore, oral administration of βGlus-PNP/pCAR-GFP resulted in significant GFP protein expression detectable within pancreatic tumor tissues. ConclusionThis study successfully constructed and validated an orally administrable, pancreatic cancer-targeting polypeptide-based nano-gene delivery system. It provides an important technological foundation in delivery systems and experimental basis for the subsequent development of in situ CAR-M-based therapeutic strategies for pancreatic cancer.
3.Effects of blue light through the brain-kidney axis of rats on the formation of kidney stones
Daocheng FANG ; Liling XIE ; Linjie QUAN ; Kui ZHANG ; Hui WEN
Journal of Modern Urology 2025;30(3):257-260
Objective: To analyze the effects of blue light on the formation of kidney stones. Methods: A total of 40 rats were randomly divided into 4 groups:A,B,C,and D,with 10 rats in each group.Rats in groups C and D were administered with a mixture of 10 g/L ethylene glycol,20 g/L ammonium chloride,and 100 g/L calcium gluconate via gavage (2 mL per mouse),while rats in groups A and B received an equal volume of physiological saline via gavage.From the second day after gavage,rats in groups A and C were subjected to twice-daily blue light irradiation (one hour per session) as an intervention,while rats in groups B and D were subjected to fluorescent lamp irradiation using the same method.After 4 weeks of intervention,the 24-hour urine samples were collected,and the rats were then euthanized for the collection of blood and kidney tissue samples.Serum levels of antidiuretic hormone (ADH),urinary Ca
,and urinary oxalate (Oxa) were measured.Levels of malondialdehyde (MDA) and superoxide dismutase (SOD) in kidney tissues were detected using ELISA.Von Kossa staining was performed to observe pathological changes in kidney tissues and the presence of calcium salt crystals in the kidneys. Results: Compared with groups A and B,groups C and D showed higher accumulation of calcium salt crystals in renal tissues,as well as elevated levels of ADH,urinary Ca
,urinary Oxa,and MDA in renal tissues, additionally,the SOD level in renal tissues was lower (P<0.05).Compared with group D,group C exhibited higher accumulation of calcium salt crystals in renal tissues,along with increased levels of ADH,urinary Ca
,urinary Oxa,and MDA in renal tissues;conversely,the SOD level in renal tissues was lower (P<0.05). Conclusion: Blue light may increase the formation of kidney stones in rats by promoting the secretion of ADH in serum and oxidative stress in kidney tissues through the brain-kidney axis.
4.Effects of combined hypoxia and irradiation on mouse bone marrow hematopoietic cells
Xinhai YANG ; Fang CHEN ; Yong QUAN ; Mengjia HU ; Yukai LU ; Naicheng CHEN ; Yang XU ; Song WANG ; Junping WANG
Journal of Army Medical University 2025;47(7):681-690
Objective To determine the effects of hypoxia pre-treatment combined with radiation damage on the hematopoietic cells in the bone marrow of mice.Methods A total of 165 male C57BL/6 mice(10~12 weeks old,weighing 20~25 g)were randomly divided into 7 groups:normal control(Control,n=33),6 Gy irradiation(6-Gy,n=43),7 d hypoxia-6 Gy irradiation(Hy-7 d+6 Gy,n=43),7 Gy irradiation(7 Gy,n=12),7 d hypoxia-7 Gy irradiation(Hy-7 d+7 Gy,n=12),7 Gy continuous hypoxia treatment(Hy-7 d+7 Gy+Hy,n=12),and 6 Gy continuous hypoxia treatment(Hy-7 d+6 Gy+Hy,n=10).The mice of the hypoxia treatment groups were given 7-day hypoxic pretreatment(12%oxygen)in a normobaric hypoxic chamber,while those of the other groups were housed in normoxic condition.After pretreatment,the mice of the irradiation groups were exposed to a single 6 or 7 Gy of whole-body 60Co γ-irradiation in normoxia.The mice of the hypoxia and irradiation groups were kept in hypoxic condition in 24 h post-irradiation followed by being resumed to normoxia,while those of the continuous hypoxia treatment groups were remained in hypoxia.After bone marrow cell suspensions were prepared from the Control,6 Gy,and Hy-7 d+6 Gy groups,bone marrow nucleated cells(BMNCs)were counted via automated cell counter.HE staining was employed to observe pathologic changes in medullary cavity,and flow cytometry was used to assess Lin-Sca1?c-Kit?(LSK)hematopoietic stem/progenitor cells,myeloid progenitors(MPs),and mature T/B/myeloid cells.The mice of the 7 Gy,Hy-7 d+7 Gy,and Hy-7 d+7 Gy+Hy groups were monitored for 30-day survival after hypoxic pretreatment.The dynamic changes in the counts of red blood cells(RBC),white blood cells(WBC)and platelets(PLT),and hemoglobin(HGB)level were observed in the 6 Gy,Hy-7 d+6 Gy,and Hy-7 d+6 Gy+Hy groups with aid of a fully automatic blood analyzer.Single-cell RNA sequencing was performed on bone marrow cell suspension derived from the mice euthanized in 17 d after irradiation from the Control,6 Gy,and Hy-7 d+6 Gy groups.Results ①Compared to the Control group,the 6 Gy group showed significantly reduced BMNCs(P<0.01),dilated bone marrow sinusoids,and erythrocyte extravasation.The Hy-7 d+6 Gy group exhibited higher cellular density and attenuated BMNC loss than the 6 Gy group(P<0.01).②Flow cytometry revealed less LSK,MP,and mature T/B/myeloid cells in the 6 Gy group than the Control group(P<0.05),and the reduced counts of LSK and MP were mitigated in the Hy-7 d+6 Gy group(P<0.01).③The Hy-7 d+7 Gy group demonstrated improved 30-day survival than the 7 Gy group(P<0.01),while continuous hypoxia(Hy-7 d+7 Gy+Hy)failed to enhance the survival.No statistical difference was seen in the survival rate between the 2 groups(P=0.12),though the Hy-7 d+7 Gy group showing higher survival rate.④Routine blood test revealed that the Hy-7 d+6 Gy group showed faster WBC recovery(vs the 6 Gy and Hy-7 d+6 Gy+Hy groups,P<0.05),higher pre-irradiation RBC/HGB levels,and accelerated PLT restoration(P<0.05).⑤Single-cell RNA sequencing indicated that hypoxia pretreatment suppressed the numbers of long-term hematopoietic stem cells/short-term hematopoietic stem cells(LT-HSC/ST-HSC)depletion in the Hy-7 d+6 Gy group when compared with the 6 Gy group,which was consistent with the results of flow cytometry.Pseudotime trajectory aligned the Hy-7 d+6 Gy group,as the Control group,showed enriched undifferentiated LSKs.Differential gene analysis and Kyoto Encyclopedia of Genes and Genomes(KEGG)analysis revealed that oxidative phosphorylation pathway was strongly activated in the 6 Gy group,while the Hy-7 d+6 Gy group had enriched in chromatin remodeling and mRNA surveillance pathways.Conclusion Hypoxic preconditioning alleviates radiation-induced bone marrow injury,and post-irradiation normoxia restoration promotes hematopoietic recovery in acute radiation-exposed mice.
5.Expert consensus on peri-implant keratinized mucosa augmentation at second-stage surgery.
Shiwen ZHANG ; Rui SHENG ; Zhen FAN ; Fang WANG ; Ping DI ; Junyu SHI ; Duohong ZOU ; Dehua LI ; Yufeng ZHANG ; Zhuofan CHEN ; Guoli YANG ; Wei GENG ; Lin WANG ; Jian ZHANG ; Yuanding HUANG ; Baohong ZHAO ; Chunbo TANG ; Dong WU ; Shulan XU ; Cheng YANG ; Yongbin MOU ; Jiacai HE ; Xingmei YANG ; Zhen TAN ; Xiaoxiao CAI ; Jiang CHEN ; Hongchang LAI ; Zuolin WANG ; Quan YUAN
International Journal of Oral Science 2025;17(1):51-51
Peri-implant keratinized mucosa (PIKM) augmentation refers to surgical procedures aimed at increasing the width of PIKM. Consensus reports emphasize the necessity of maintaining a minimum width of PIKM to ensure long-term peri-implant health. Currently, several surgical techniques have been validated for their effectiveness in increasing PIKM. However, the selection and application of PIKM augmentation methods may present challenges for dental practitioners due to heterogeneity in surgical techniques, variations in clinical scenarios, and anatomical differences. Therefore, clear guidelines and considerations for PIKM augmentation are needed. This expert consensus focuses on the commonly employed surgical techniques for PIKM augmentation and the factors influencing their selection at second-stage surgery. It aims to establish a standardized framework for assessing, planning, and executing PIKM augmentation procedures, with the goal of offering evidence-based guidance to enhance the predictability and success of PIKM augmentation.
Humans
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Consensus
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Dental Implants
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Mouth Mucosa/surgery*
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Keratins
6.Exploration of Rat Fetal Lung Tissue Fixation Methods
Liyu LIU ; Bo JI ; Xiaoxuan LIU ; Yang FANG ; Ling ZHANG ; Tingting GUO ; Ye QUAN ; Hewen LI ; Yitian LIU
Laboratory Animal and Comparative Medicine 2025;45(4):432-438
ObjectiveThis study explores the methods of lung tissue extraction and fixation required for pathological studies of fetal rats, based on the unique physiological structure of fetal rat lung tissue and existing lung tissue fixation techniques for adult rats. MethodsSix pregnant adult SD rats at 20.5 days of gestation were subjected to cesarean section to obtain fetal rats. Four healthy fetal rats with similar body weight, vital signs, and respiratory status were selected from each pregnant rat, and they were randomly divided into the following groups using a random number table: direct lung infiltration group, lung infiltration group after intratracheal infusion, whole-body infiltration group of fetal rats, and whole-body infiltration group after intratracheal infusion of fetal rats. To systematically compare and analyze the anatomical morphology under different fixation methods, lung tissues from four groups of fetal rats were harvested, perfused, and fixed, and the gross morphology of lung tissues in each group was observed. Paraffin sections were prepared and stained with Hematoxylin-Eosin (H&E). The histological morphology of the whole lung, alveoli, and bronchi was further examined under optical microscopy. ResultsIn the direct lung infiltration group, the hilar structures were unclear, lung lobation was indistinct, the shape was irregular, lung cavities were small, and alveoli and bronchi were shrunken. In the lung infiltration group after intratracheal infusion, the hilar structures were clear, lobation was pronounced, the shape was regular, lung cavities were large, and alveoli and bronchi were full. Both the whole-body infiltration group and whole-body infiltration group after intratracheal infusion of fetal rats exhibited visible lungs, hearts, skins, and other organs. The lung tissues of both groups showed obvious lobulation, irregular shape, and damage at the margins of lung lobes. In the whole-body infiltration group, the thoracic cavities of the fetus were flattened, lung cavities were small, and alveoli and bronchi were shrunken. In the whole-body infiltration group after intratracheal infusion of fetal rats, the fetal thoracic cavities were full, lung cavities were large, and alveoli and bronchi were relatively full. ConclusionThe lung infiltration after intratracheal infusion method for fetal rat lung tissue fixation outperforms direct lung infiltration, whole-body infiltration of fetal rats, and whole-body infiltration after intratracheal infusion of fetal rats in terms of preservation of the lung tissue's original morphology, paraffin sectioning, staining, and pathological observation and analysis. The embedding, sectioning, and staining processes are also simple and save consumables. Therefore, intratracheal infusion followed by lung infiltration method is recommended for fixation in histopathological observation of fetal rat lung tissue.
7.Maintenance of MAQUET ROTAFLOW ECMO system:Four case reports
Zeng-qiang FANG ; Bin-quan WANG ; Li-gang LOU ; Jing-yi FENG
Chinese Medical Equipment Journal 2025;46(5):116-120
The composition and working principle of MAQUET ROTAFLOW ECMO system were introduced.Four cases of common failures of ROTAFLOW ECMO systems were analyzed in terms of the cause and elimination method.The methods for the maintenance and quality control of ECMO system were put forward.References were provided for engineering technicians to treat similar faults.[Chinese Medical Equipment Journal,2025,46(5):116-120]
8.Research on the physical anatomical structure of the Lieque(LU7)acupoint
Chunlin WANG ; Zhaoyu SHU ; Shuai ZHANG ; Quan HAN ; Peigang FANG ; Hengtao QI ; Tiezheng WANG ; Ziyu KANG ; Wenxu ZHANG ; Linjiang WANG ; Qiang WANG ; Likun DONG ; Tao WANG ; Zengtao WANG
Journal of Beijing University of Traditional Chinese Medicine 2025;48(7):992-999
Objective To investigate the anatomical structure and surface location of the Lieque(LU7)acupoint.Methods Firstly,the anatomical localization descriptions of the Lieque(LU7)acupoint from classical medical literature were reviewed and summarized.A total of 21 participants were recruited from Shandong Provincial Hospital Affiliated to Shandong First Medical University from January to March 2025.A Cartesian coordinate system was established over the Lieque(LU7)region on the right forearm.Following standardized manual pressure stimulation,the coordinates of the participant′s reported acupoint sensations were recorded.Based on surface pressure mapping result,10 participants were arbitrarily selected for acupuncture intervention.Upon elicitation of acupoint sensation,the ultrasound imaging was used for real-time visualization of anatomical spatial relationships between the needle tip and distal radial osseous landmarks.Five red latex-perfused adult upper limb specimens were selected for microdissection of the Lieque(LU7)regions pre-localized via ultrasonography,achieving definitive structural characterization of its anatomical strata.Another 10 participants were arbitrarily selected to find the physical structure of the Lieque(LU7)acupoint using ultrasound,and the similarities and differences of acupoint sensation responses were verified using acupuncture needle insertions into both the demarcated zone and peripheral tissues.Results The descriptions of the localization of the Lieque(LU7)acupoint in ancient books can be summarized as"one and a half cun above the wrist side"longitudinally,and"at the intersection head,between two tendons and two bones in the hollow"transversely.During surface pressure application,the sites of the participant′s elicited acupoint sensation were anatomically concentrated in the proximal depression adjacent to the radiopalmar ridge,specifically at the transitional interface between the extensor pollicis brevis tendon and scaphoid bone.During acupuncture-induced acupoint sensation,ultrasound imaging demonstrated that the location of the needle tip was located within the proximal depression adjacent to the radiopalmar ridge,accompanied by arterial hemodynamic perfusion signals into adjacent osseous interfaces.Microdissection findings revealed perforating branches of the radial artery traversing the cortical bone interface within the Lieque(LU7)acupoint region.Acupuncture stimulation at the proximal depression adjacent to the radiopalmar ridge elicited consistent acupoint sensations in all 10 participants,and the acupoint sensations differed from those of other surrounding tissues.Conclusion The anatomical structure of Lieque(LU7)acupoint is located within the proximal depression adjacent to the radiopalmar ridge,characterized by the presence of"hilus of bone"structure.
9.Expert Consensus on the Ethical Requirements for Generative AI-Assisted Academic Writing
You-Quan BU ; Yong-Fu CAO ; Zeng-Yi CHANG ; Hong-Yu CHEN ; Xiao-Wei CHEN ; Yuan-Yuan CHEN ; Zhu-Cheng CHEN ; Rui DENG ; Jie DING ; Zhong-Kai FAN ; Guo-Quan GAO ; Xu GAO ; Lan HU ; Xiao-Qing HU ; Hong-Ti JIA ; Ying KONG ; En-Min LI ; Ling LI ; Yu-Hua LI ; Jun-Rong LIU ; Zhi-Qiang LIU ; Ya-Ping LUO ; Xue-Mei LV ; Yan-Xi PEI ; Xiao-Zhong PENG ; Qi-Qun TANG ; You WAN ; Yong WANG ; Ming-Xu WANG ; Xian WANG ; Guang-Kuan XIE ; Jun XIE ; Xiao-Hua YAN ; Mei YIN ; Zhong-Shan YU ; Chun-Yan ZHOU ; Rui-Fang ZHU
Chinese Journal of Biochemistry and Molecular Biology 2025;41(6):826-832
With the rapid development of generative artificial intelligence(GAI)technologies,their widespread application in academic research and writing is continuously expanding the boundaries of sci-entific inquiry.However,this trend has also raised a series of ethical and regulatory challenges,inclu-ding issues related to authorship,content authenticity,citation accuracy,and accountability.In light of the growing involvement of AI in generating academic content,establishing an open,controllable,and trustworthy ethical governance framework has become a key task for safeguarding research integrity and maintaining trust within the academic community.This expert consensus outlines ethical requirements across key stages of AI-assisted academic writing-including topic selection,data management,citation practices,and authorship attribution.It aims to clarify the boundaries and ethical obligations surrounding AI use in academic writing,ensuring that technological tools enhance efficiency without compromising in-tegrity.The goal is to provide guidance and institutional support for building a responsible and sustainable research ecosystem.
10.Nogo-A Protein Mediates Oxidative Stress and Synaptic Damage Induced by High-Altitude Hypoxia in the Rat Hippocampus.
Jin Yu FANG ; Huai Cun LIU ; Yan Fei ZHANG ; Quan Cheng CHENG ; Zi Yuan WANG ; Xuan FANG ; Hui Ru DING ; Wei Guang ZHANG ; Chun Hua CHEN
Biomedical and Environmental Sciences 2025;38(1):79-93
OBJECTIVE:
High-altitude hypoxia exposure often damages hippocampus-dependent learning and memory. Nogo-A is an important axonal growth inhibitory factor. However, its function in high-altitude hypoxia and its mechanism of action remain unclear.
METHODS:
In an in vivo study, a low-pressure oxygen chamber was used to simulate high-altitude hypoxia, and genetic or pharmacological intervention was used to block the Nogo-A/NgR1 signaling pathway. Contextual fear conditioning and Morris water maze behavioral tests were used to assess learning and memory in rats, and synaptic damage in the hippocampus and changes in oxidative stress levels were observed. In vitro, SH-SY5Y cells were used to assess oxidative stress and mitochondrial function with or without Nogo-A knockdown in Oxygen Glucose-Deprivation/Reperfusion (OGD/R) models.
RESULTS:
Exposure to acute high-altitude hypoxia for 3 or 7 days impaired learning and memory in rats, triggered oxidative stress in the hippocampal tissue, and reduced the dendritic spine density of hippocampal neurons. Blocking the Nogo-A/NgR1 pathway ameliorated oxidative stress, synaptic damage, and the learning and memory impairment induced by high-altitude exposure.
CONCLUSION:
Our results demonstrate the detrimental role of Nogo-A protein in mediating learning and memory impairment under high-altitude hypoxia and suggest the potential of the Nogo-A/NgR1 signaling pathway as a crucial therapeutic target for alleviating learning and memory dysfunction induced by high-altitude exposure.
GRAPHICAL ABSTRACT
available in www.besjournal.com.
Animals
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Oxidative Stress
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Hippocampus/metabolism*
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Rats
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Nogo Proteins/genetics*
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Male
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Rats, Sprague-Dawley
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Hypoxia/metabolism*
;
Altitude
;
Synapses
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Humans
;
Altitude Sickness/metabolism*

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