1.Construction of Silver Nanoparticle-based Artificial Hydrolases via Conformational Engineering and Study of Its Catalytic Mechanism
Yan WANG ; Tong-Tong ZHOU ; Yuan GUO ; Hai-Fang WANG ; Ao-Neng CAO
Progress in Biochemistry and Biophysics 2026;53(6):1684-1698
ObjectiveThis study employs a special conformational engineering (CE) technology to construct an α-chymotrypsin-like active center, which includes a catalytic triad, an oxyanion hole, and a substrate-binding site, on silver nanoparticles (AgNPs), thereby creating an AgNP-based artificial hydrolase with high catalytic activity. This study provides a new approach for the design of highly efficient artificial enzymes and enzyme-mimicking. MethodsAgNPs were chosen as the scaffold to build the an α-chymotrypsin-like active center. A special CE procedure enables the designed peptide, Triad5, to adopt an α‑helical conformation on AgNPs, with the key catalytic residues located on one side of the α-helix forming a catalytic active center with a catalytic triad, an oxyanion hole, and a substrate-binding site. The CE procedure consists of three steps, including conformation induction via trifluoroethanol (TFE), conformation stabilization on AgNPs via Ag-S bonds, and TFE removal via lyophilization. Circular dichroism (CD) spectra were used to confirm the formation and stabilization of the α-helix conformation. Mutations of the key residues combined with stopped-flow kinetic experiments were used to demonstrate the indispensability of each key residue and the synergistic effects among the catalytic triad, the oxyanion hole, and the substrate-binding site. ResultsCD spectra show that the designed Triad5 alone is in random coil conformation; when conjugated on AgNPs, Triad5 still remains largely unstructured; but after the CE treatment, Triad5 adopts a typical α-helical conformation on AgNPs as designed, thus produces an AgNP-based artificial hydrolase, Silverzyme. Silverzyme exhibits extremely high hydrolytic activity towards p-nitrophenyl acetate (p-NPA), with an extremely high catalytic turnover number per active site of 3.5 s-1, which is even higher than that of α-chymotrypsin. As a comparison, the AgNP-Triad5 conjugate without CE treatment shows much lower catalytic activity than Silverzyme, highlighting the important role of the right conformation of the active center for the catalytic activity and the power of the CE treatment. When the key residues of the catalytic triad of Silverzyme were mutated to alanine, the overall catalytic efficiency of this mutant dropped by about 2 orders of magnitude, unambiguously demonstrating the key role of the designed catalytic triad. Similarly, when the residues for the oxyanion hole were deleted, the mutant with the intact catalytic triad also showed significantly decreased catalytic activity, highlighting the indispensable role of the oxyanion hole for the catalytic activity. Unexpectedly, when both the catalytic triad and the oxyanion hole were kept intact, a slight change of the binding site also resulted in significantly decreased catalytic activity, indicating that the designed binding site is at the right position to align the substrate in the right orientation in the active center for catalytic hydrolysis. These results confirm the synergy among the catalytic triad, the oxyanion hole, and the substrate-binding site, indicating successful mimicking of the active center of α-chymotrypsin. Moreover, Silverzyme shows better thermal stability than α-chymotrypsin, and can even hydrolyze the tough non-activated ester diethyl phthalate, a priority pollutant by the United States Environmental Protection Agency (USEPA). ConclusionThis study successfully mimicked the complex catalytic active center of α-chymotrypsin using a conformational engineering strategy, and produced a highly active artificial hydrolase with a well-defined structure and catalytic mechanism. The findings highlight the significant potential of conformational engineering.
2.Hippocampal Extracellular Matrix Protein Laminin β1 Regulates Neuropathic Pain and Pain-Related Cognitive Impairment.
Ying-Chun LI ; Pei-Yang LIU ; Hai-Tao LI ; Shuai WANG ; Yun-Xin SHI ; Zhen-Zhen LI ; Wen-Guang CHU ; Xia LI ; Wan-Neng LIU ; Xing-Xing ZHENG ; Fei WANG ; Wen-Juan HAN ; Jie ZHANG ; Sheng-Xi WU ; Rou-Gang XIE ; Ceng LUO
Neuroscience Bulletin 2025;41(12):2127-2147
Patients suffering from nerve injury often experience exacerbated pain responses and complain of memory deficits. The dorsal hippocampus (dHPC), a well-defined region responsible for learning and memory, displays maladaptive plasticity upon injury, which is assumed to underlie pain hypersensitivity and cognitive deficits. However, much attention has thus far been paid to intracellular mechanisms of plasticity rather than extracellular alterations that might trigger and facilitate intracellular changes. Emerging evidence has shown that nerve injury alters the microarchitecture of the extracellular matrix (ECM) and decreases ECM rigidity in the dHPC. Despite this, it remains elusive which element of the ECM in the dHPC is affected and how it contributes to neuropathic pain and comorbid cognitive deficits. Laminin, a key element of the ECM, consists of α-, β-, and γ-chains and has been implicated in several pathophysiological processes. Here, we showed that peripheral nerve injury downregulates laminin β1 (LAMB1) in the dHPC. Silencing of hippocampal LAMB1 exacerbates pain sensitivity and induces cognitive dysfunction. Further mechanistic analysis revealed that loss of hippocampal LAMB1 causes dysregulated Src/NR2A signaling cascades via interaction with integrin β1, leading to decreased Ca2+ levels in pyramidal neurons, which in turn orchestrates structural and functional plasticity and eventually results in exaggerated pain responses and cognitive deficits. In this study, we shed new light on the functional capability of hippocampal ECM LAMB1 in the modulation of neuropathic pain and comorbid cognitive deficits, and reveal a mechanism that conveys extracellular alterations to intracellular plasticity. Moreover, we identified hippocampal LAMB1/integrin β1 signaling as a potential therapeutic target for the treatment of neuropathic pain and related memory loss.
Animals
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Laminin/genetics*
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Hippocampus/metabolism*
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Neuralgia/metabolism*
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Cognitive Dysfunction/etiology*
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Male
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Peripheral Nerve Injuries/metabolism*
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Extracellular Matrix/metabolism*
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Integrin beta1/metabolism*
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Pyramidal Cells/metabolism*
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Signal Transduction
4.Analysis of early efficacy and safety of hip arthroscopy in patients with borderline developmental dysplasia of the hip.
Ke AI ; Lei WANG ; Jun YANG ; Jie-Neng CHEN
China Journal of Orthopaedics and Traumatology 2025;38(8):828-834
OBJECTIVE:
To explore the early efficacy and safety of hip arthroscopy in the treatment of patients with borderline developmental dysplasia of the hip(BDDH).
METHODS:
A total of 111 patients diagnosed with BDDH from January 2020 to December 2022 were selected and divided into two groups according to the surgical method. Among them, 63 patients who underwent arthroscopy were assigned to the arthroscopy group, including 22 males and 41 females with an average age of (35.67±6.83) years;48 patients who underwent periacetabular osteotomy were assigned to the PAO group, including 18 males and 30 females with an average age of (36.85±7.10) years. The operation time, hospital stay, blood loss, rehabilitation time, complication rate, and reoperation rate were recorded in both groups. Imaging indicators of the two groups were measured and recorded. The modified Harris hip score (mHHS), nonarthritic hip score (NAHS), and hip outcome score-activity of daily living scale (HOS-ADL) were used to evaluate hip function and quality of life before and after surgery.
RESULTS:
All patients were followed up for 12 months. The operation time (90.43±9.85) min, hospital stay(4.32±0.56) days, rehabilitation time (15.22±2.15) weeks, blood loss (25.69±6.57) ml, and number of complications (15 cases) in the arthroscopy group were all lower than those in the PAO group (117.25±15.83) min, (5.81±0.92) days, (21.10±3.74) weeks, (358.52±126.73) ml, 30 cases, with statistically significant differences (P<0.05). At the last follow-up after treatment, the lateral center edge angle (LCEA) (19.82±1.90)° and anterior center edge angle (ACEA) (20.01±1.85)° in the arthroscopy group decreased compared with those before treatment (21.43±2.10)°, (21.54±2.05)°, while in the PAO group, the LCEA (33.03±3.45)° and ACEA (33.48±4.22)° at the last follow-up after treatment increased compared with those before treatment, with statistically significant differences (P<0.05). The T?nnis angle in the arthroscopy group after treatment (11.05±1.83)° increased compared with that before treatment, while in the PAO group, the T?nnis angle at the last follow-up after treatment (2.98±0.75)° decreased compared with that before treatment, with statistically significant differences (P<0.05). In the arthroscopy group, the extrusion index (30.68±2.85) and T?nnis grade after treatment increased compared with those before treatment, while the α angle after treatment (38.79±4.27)° significantly decreased compared with that before treatment, with statistically significant differences (P<0.05);in the PAO group, the extrusion index (15.03±2.18) and α angle (53.58±6.02)° after treatment significantly decreased compared with those before treatment, with statistically significant differences (P<0.05). The mHHS score at the last follow-up after treatment in the arthroscopy group (86.41±7.33) was higher than that in the PAO group (81.02±6.49), with a statistically significant difference (P<0.05). At 6 months after treatment, the NAHS (69.83±6.53) and HOS-ADL scores (78.84±7.39) in the arthroscopy group were higher than those in the PAO group (64.10±6.02), (75.31±7.01), with statistically significant differences (P<0.01);at the last follow-up after treatment, the NAHS (87.63±7.60) and HOS-ADL scores (88.94±8.11) in the arthroscopy group were higher than those in the PAO group (81.63±7.03), (83.63±7.92), with statistically significant differences (P<0.05).
CONCLUSION
Compared with PAO, hip arthroscopy shows better early to mid-term clinical efficacy in the treatment of BDDH patients. However, PAO has more advantages in improving acetabular imaging indicators of BDDH patients, while hip arthroscopy only improves the α angle of patients. Meanwhile, hip arthroscopy causes less trauma to patients, reduces blood loss, and is more conducive to the subsequent recovery of patients.
Humans
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Female
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Male
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Arthroscopy/methods*
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Adult
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Developmental Dysplasia of the Hip/physiopathology*
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Middle Aged
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Treatment Outcome
5.Clinical analysis of 6 cases of diffuse panbronchiolitis in children.
Li-Xin DENG ; De-Hui CHEN ; Yu-Neng LIN ; Shang-Zhi WU ; Jia-Xing XU ; Zhan-Hang HUANG ; Ying-Ying GU ; Jun-Xiang FENG
Chinese Journal of Contemporary Pediatrics 2025;27(3):334-339
OBJECTIVES:
To analyze the clinical characteristics of diffuse panbronchiolitis (DPB) in children and to enhance the clinical diagnosis and treatment of this disease.
METHODS:
A retrospective analysis was conducted on the clinical data of 6 children diagnosed with DPB who were hospitalized at The First Affiliated Hospital of Guangzhou Medical University from January 2011 to December 2019.
RESULTS:
Among the 6 patients, there were 2 males and 4 females; the age at diagnosis ranged from 7 to 12 years. All patients presented with cough, sputum production, and exertional dyspnea, and all had a history of sinusitis. Two cases showed positive serum cold agglutinin tests, and 5 cases exhibited pathological changes consistent with chronic bronchiolitis. High-resolution chest CT in all patients revealed centrilobular nodules diffusely distributed throughout both lungs with a tree-in-bud appearance. Five patients received low-dose azithromycin maintenance therapy, but 3 showed inadequate treatment response. After empirical anti-tuberculosis treatment, non-tuberculous Mycobacteria were found in the bronchoalveolar lavage fluid. Follow-up over 2 years showed 1 case cured, 3 cases significantly improved, and 2 cases partially improved.
CONCLUSIONS
The clinical presentation of DPB is non-specific and can easily lead to misdiagnosis. In cases where DPB is clinically diagnosed but does not show improvement with low-dose azithromycin treatment, special infections should be considered.
Humans
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Male
;
Female
;
Bronchiolitis/drug therapy*
;
Retrospective Studies
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Child
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Haemophilus Infections/diagnosis*
6.Brief Discussion on the General Requirements of Quality Management System of In Vitro Diagnostic Reagents Developed by Medical Institutions.
Chinese Journal of Medical Instrumentation 2025;49(2):219-223
On March 19, 2021, the National Medical Products Administration(NMPA) issued the Regulations on the Supervision and Administration of Medical Devices (Order No. 739 of the State Council of the People's Republic of China), which clearly stipulated in Article 53 the basic definition and scope of use of in vitro diagnostic reagents developed by medical institutions. It also pointed out that the relevant administrative measures shall be formulated by the Drug Regulatory Department of the State Council in conjunction with the Health Department of the State Council. This initiative marks the re-incorporation of in vitro diagnostic reagents developed by medical institutions into China's regulatory system. This study reviewed the development of regulatory policies for self-developed in vitro diagnostic reagents at home and abroad, combined with the Key Points of On-site Verification of Self-developed In Vitro Diagnostic Reagents in Shanghai Medical Institutions issued by the Shanghai Municipal Drug Administration, in conjunction with the Shanghai Municipal Health Commission, and the specific verification work of pre-record evaluation, and sorted out the general requirements for the quality management system of self-developed in vitro diagnostic reagents. The purpose is to provide some references for the further development of this pilot work and its nationwide promotion.
China
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Quality Control
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Indicators and Reagents/standards*
;
Reagent Kits, Diagnostic/standards*
7.Analysis of treatment response and post-discontinuation efficacy maintenance of cyclophosphamide monotherapy in T-cell large granular lymphocytic leukemia
Lele ZHANG ; Linzhu TIAN ; Hong PAN ; Zhen GAO ; Weiwang LI ; Ruonan LI ; Jingyu ZHAO ; Jinbo HUANG ; Xin ZHAO ; Jianping LI ; Neng NIE ; Xiao YU ; Liyun LI ; Zhexiang KUANG ; Liwei FANG ; Jun SHI
Chinese Journal of Hematology 2025;46(7):631-635
Objective:To evaluate the efficacy of cyclophosphamide in patients with T-cell large granular lymphocytic leukemia (T-LGLL) and the maintenance of treatment-free remission (TFR) following drug discontinuation.Methods:Clinical data were collected from 37 patients with T-LGLL who received oral cyclophosphamide at the Regenerative Medicine Clinic of the Institute of Hematology and Blood Diseases Hospital between June 2019 and March 2024. Patient clinical characteristics, treatment efficacy, and long-term TFR were analyzed.Results:The median age of the 37 patients was 60 years (range: 37-86), and 22 (59.5%) were male. Anemia was observed in 30 patients (81.1%), and 28 (75.7%) met the diagnostic criteria for secondary pure red cell aplasia. Neutropenia occurred in 15 patients (40.5%), lymphocytosis in 11 (29.7%), and thrombocytopenia in three (8.1%). Sixteen patients (43.2%) had not received prior immunosuppressive therapy (treatment-naive group), while 21 patients (56.8%) were refractory to or had relapsed after immunosuppressive treatment (refractory/relapsed group). All patients met the treatment criteria and received oral cyclophosphamide at doses of 50-100 mg/day. Among the 36 evaluable patients, hematologic remission was achieved in 25 (69.4%), with a median time of 2.0 months (range: 0.7-7.0). There was no statistically significant difference in remission rates between the treatment-naive and refractory/relapsed groups (68.5% vs. 66.7%, P=0.589). Among the 25 patients who achieved hematologic remission, 24 discontinued cyclophosphamide. With a median follow-up of 39.0 months (range: 8.0-56.0), the median TFR duration was not reached. The estimated TFR rates were (90.87± 6.16) % at 12 months and (75.72±11.04) % at 36 months. No significant difference in TFR was observed between the treatment-naive and refractory/relapsed groups ( P=0.451) . Conclusion:Oral cyclophosphamide is effective in the treatment of T-LGLL, and patients may maintain long-term TFR following drug discontinuation.
8.Electroacupuncture alleviates behaviors associated with posttraumatic stress disorder by modulating lipocalin-2-mediated neuroinflammation and neuronal activity in the prefrontal cortex.
Yu-Die YANG ; Wen ZHONG ; Ming CHEN ; Qing-Chen TANG ; Yan LI ; Lu-Lu YAO ; Mei-Qi ZHOU ; Neng-Gui XU ; Shuai CUI
Journal of Integrative Medicine 2025;23(5):537-547
OBJECTIVE:
To elucidate the specific mechanisms by which electroacupuncture (EA) alleviates anxiety and fear behaviors associated with posttraumatic stress disorder (PTSD), focusing on the role of lipocalin-2 (Lcn2).
METHODS:
The PTSD mouse model was subjected to single prolonged stress and shock (SPS&S), and the animals received 15 min sessions of EA at Shenmen acupoint (HT7). Behavioral tests were used to investigate the effects of EA at HT7 on anxiety and fear. Western blotting and enzyme-linked immunosorbent assay were used to quantify Lcn2 and inflammatory cytokine levels in the prefrontal cortex (PFC). Additionally, the activity of PFC neurons was evaluated by immunofluorescence and in vivo electrophysiology.
RESULTS:
Mice subjected to SPS&S presented increased anxiety- and fear-like behaviors. Lcn2 expression in the PFC was significantly upregulated following SPS&S, leading to increased expression of the proinflammatory cytokines tumor necrosis factor-α and interleukin-6 and suppression of PFC neuronal activity. However, EA at HT7 inhibited Lcn2 release, reducing neuroinflammation and hypoexcitability in the PFC. Lcn2 overexpression mitigated the effects of EA at HT7, resulting in anxiety- and fear-like behaviors.
CONCLUSION
EA at HT7 can ameliorate PTSD-associated anxiety and fear, and its mechanism of action appears to involve the inhibition of Lcn2-mediated neural activity and inflammation in the PFC. Please cite this article as: Yang YD, Zhong W, Chen M, Tang QC, Li Y, Yao LL, et al. Electroacupuncture alleviates behaviors associated with posttraumatic stress disorder by modulating lipocalin-2-mediated neuroinflammation and neuronal activity in the prefrontal cortex. J Integr Med. 2025; 23(5):537-547.
Electroacupuncture
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Stress Disorders, Post-Traumatic/metabolism*
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Animals
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Lipocalin-2/metabolism*
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Prefrontal Cortex/physiopathology*
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Male
;
Mice
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Neurons/physiology*
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Disease Models, Animal
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Fear
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Behavior, Animal
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Mice, Inbred C57BL
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Neuroinflammatory Diseases/metabolism*
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Anxiety/therapy*
;
Acupuncture Points
9.Baicalin improves acute liver injury in septic mice by inhibiting the TLR4/NF-κB pathway
Jin WANG ; Haowen SUN ; Tielong WU ; Tianhao LIU ; Yilin REN ; Lei ZHANG ; Neng BAO ; Yuanyuan DAI ; Yingyue SHEN ; Yi XU ; Yuzheng XUE
Chinese Journal of Hepatobiliary Surgery 2025;31(10):772-778
Objective:To investigate the mechanisms of baicalin in treating septic acute liver injury through a combination of network pharmacology and animal experiments.Methods:Thirty male C57BL/6 mice (6 weeks old) were divided into five groups ( n=6): control group (normal saline), model group [lipopolysaccharide (LPS) 10 mg/kg, intraperitoneal injection], low-dose baicalin group (10 mg/kg), high-dose baicalin group (20 mg/kg), and baicalin-only group (20 mg/kg, without LPS). Baicalin was administered orally for 14 consecutive days prior to modeling. Mice were sacrificed 24 h after LPS injection. Alanine transaminase, aspartate transaminase liver tissue histopathology were measured; neutrophil infiltration was visualized using immunofluorescence; mRNA expression levels of interleukin (IL)-1β, IL-17, IL-6, and tumor necrosis factor (TNF)-α were detected by RT-qPCR; and the expression of Toll-like receptor 4 (TLR4) and phosphorylated nuclear factor (NF)-κB proteins were analyzed by Western blotting. Results:In the LPS model group, the ALT, AST, and histopathological injury score were (148.60±22.02) U/L, (81.58±11.59) U/L, and 8.50(7.75, 9.25), respectively. These indicators were significantly reduced in the high-dose baicalin group with (77.90±16.79) U/L, (49.92±14.89) U/L, and 1.00(1.00, 2.25) (all P<0.05). Compared with the LPS group, neutrophil infiltration in the liver of high-dose baicalin group was also significantly reduced [1.18%(0.98%, 1.22%) vs. 6.13%(5.41%, 8.69%), P<0.05]. RT-qPCR results showed that the relative mRNA expression levels of inflammatory cytokines IL-1β [(1.03±0.06) vs. (2.60±0.34)], IL-17 [(1.21±0.12) vs. (2.94 ± 0.39)], IL-6 [(1.37±0.26) vs. (2.73±0.18)], and TNF-α [(1.18±0.10) vs. (3.30±0.92)] were significantly decreased in the high-dose baicalin group compared with the LPS group (all P<0.05). Western blot analysis revealed that the relative protein expression levels of TLR4 [(1.25±0.13) vs. (1.73±0.06)] and phosphorylated NF-κB [(1.25±0.25) vs. (1.79±0.12)] were also significantly lower in the high-dose baicalin group (both P<0.05). Conclusion:Baicalin reduces liver injury in septic mice by downregula-ting the expression of pro-inflammatory cytokines IL-1β, IL-6, TNF-α, and IL-17, potentially through the inhibition of the TLR4/NF-κB signaling pathway.
10.Effects of high-altitude hypoxia exposure on brain injury in rats based on oxidative stress and aquaporins
Xin-jue ZHANG ; Wang-jie CAO ; Yun SU ; Hong-xia GONG ; Yong HUANG ; Yong-qi LIU ; Jian-zheng HE ; Jia-wang GUO ; Neng-xian ZHANG
The Chinese Journal of Clinical Pharmacology 2025;41(1):81-85
Objective To explore the brain damage of SD rats under different time points of hypobaric hypoxia exposure.Methods A rat high-altitube cerebral edema(HACE)model was constructed by simulating an altitude of 6 000 m in a hypobaric hypoxia animal experimental chamber.Thirty-six SD male rats were randomly divided into the control group and the hypobaric hypoxia exposure 3,7 and 14 d groups,with 9 rats in each group.Except for the control group,the rats in each group were continuously exposed to hypobaric hypoxia for 3,7,and 14 d.At the end of the modeling period,serum was collected by blood sampling via the abdominal aorta,and brain tissue samples were taken.The wet-to-dry ratio(W/D)of brain tissue was calculated,and the levels of relevant oxidative enzymes in serum and brain tissue were measured.The expression levels of hypoxia-inducible factor-1α(HIF-1α)and aquaporin 4(AQP4)mRNAs in brain tissue were detected by real-time fluorescence quantitative polymerase chain reaction.Results The W/D of brain tissues in the control group and the group exposed to hypobaric hypoxia for 3,7 and 14 d were 4.46±0.12,4.98±0.16,5.07±0.18 and 4.95±0.07;the superoxide dismutase contents were(111.86±2.45),(90.73±1.48),(79.64±2.56)and(55.33±1.45)U·g-1;the glutathione contents were(126.91±5.18),(125.26±1.53),(56.20±2.17)and(122.73±1.78)μg·mL-1;the malondialdehyde contents were(230.94±2.00),(362.65±3.28),(407.34±3.47)and(237.50±1.59)nmol·g-1;the relative expression levels of HIF-1 α mRNA were 1.00±0,2.99±0.49,4.72±0.49 and 1.91±0.28;the relative expression levels of AQP4 mRNA were 1.00±0,2.62±0.34,8.38±0.84 and 5.27±0.42,respectively.Statistically significant differences were found between the above indexes in the 3,7 and 14 d of hypobaric hypoxia exposure group compared with the control group(P<0.05,P<0.01).Conclusion Different time of hypobaric hypoxia exposure can up-regulate the expression of AQPs proteins in HACE rats and cause the disruption of the blood-brain barrier,and the HACE model constructed in the hypobaric hypoxia chamber with 6 000 m intervention for 7 d was more stable.

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