1.Oxidative Stress-related Signaling Pathways and Antioxidant Therapy in Alzheimer’s Disease
Li TANG ; Yun-Long SHEN ; De-Jian PENG ; Tian-Lu RAN ; Zi-Heng PAN ; Xin-Yi ZENG ; Hui LIU
Progress in Biochemistry and Biophysics 2025;52(10):2486-2498
Alzheimer’s disease (AD) is a neurodegenerative disorder characterized by progressive cognitive decline, functional impairment, and neuropsychiatric symptoms. It represents the most prevalent form of dementia among the elderly population. Accumulating evidence indicates that oxidative stress plays a pivotal role in the pathogenesis of AD. Notably, elevated levels of oxidative stress have been observed in the brains of AD patients, where excessive reactive oxygen species (ROS) can cause extensive damage to lipids, proteins, and DNA, ultimately compromising neuronal structure and function. Amyloid β‑protein (Aβ) has been shown to induce mitochondrial dysfunction and calcium overload, thereby promoting the generation of ROS. This, in turn, exacerbates Aβ aggregation and enhances tau phosphorylation, leading to the formation of two pathological features of AD: extracellular Aβ plaque deposition and intracellular neurofibrillary tangles (NFTs). These events ultimately culminate in neuronal death, forming a vicious cycle. The interplay between oxidative stress and these pathological processes constitutes a core link in the pathogenesis of AD. The signaling pathways mediating oxidative stress in AD include Nrf2, RCAN1, PP2A, CREB, Notch1, NF‑κB, ApoE, and ferroptosis. Nrf2 signaling pathway serves as a key regulator of cellular redox homeostasis, exerts important antioxidant capacity and protective effects in AD. RCAN1 signaling pathway, as a calcineurin inhibitor, and modulates AD progression through multiple mechanisms. PP2A signaling pathway is involved in regulating tau phosphorylation and neuroinflammation processes. CREB signaling pathway contributes to neuroplasticity and memory formation; activation of CREB improves cognitive function and reduce oxidative stress. Notch1 signaling pathway regulates neuronal development and memory, participates in modulation of Aβ production, and interacts with Nrf2 toco-regulate antioxidant activity. NF‑κB signaling pathway governs immune and inflammatory responses; sustained activation of this pathway forms “inflammatory memory”, thereby exacerbating AD pathology. ApoE signaling pathway is associated with lipid metabolism; among its isoforms, ApoE-ε4 significantly increases the risk of AD, leading to elevated oxidative stress, abnormal lipid metabolism, and neuroinflammation. The ferroptosis signaling pathway is driven by iron-dependent lipid peroxidation, and the subsequent release of lipid peroxidation products and ROS exacerbate oxidative stress and neuronal damage. These interconnected pathways form a complex regulatory network that regulates the progression of AD through oxidative stress and related pathological cascades. In terms of therapeutic strategies targeting oxidative stress, among the drugs currently used in clinical practice for AD treatment, memantine and donepezil demonstrate significant therapeutic efficacy and can improve the level of oxidative stress in AD patients. Some compounds with antioxidant effects (such asα-lipoic acid and melatonin) have shown certain potential in AD treatment research and can be used as dietary supplements to ameliorate AD symptoms. In addition, non-drug interventions such as calorie restriction and exercise have been proven to exerted neuroprotective effects and have a positive effect on the treatment of AD. By comprehensively utilizing the therapeutic characteristics of different signaling pathways, it is expected that more comprehensive multi-target combination therapy regimens and combined nanomolecular delivery systems will be developed in the future to bypass the blood-brain barrier, providing more effective therapeutic strategies for AD.
2.Construction and evaluation of novel self-assembled nanoparticles of Herpetospermum caudigerum Wall.
Yu-wen ZHU ; Xiang DENG ; Li CHEN ; Jian-tao NING ; Yu-ye XUE ; Bao-de SHEN ; Ling-yu HANG ; Hai-long YUAN
Acta Pharmaceutica Sinica 2024;59(2):448-454
It has become an industry consensus that self-assembled nanoparticles (SAN) are formed by molecular recognition of chemical components in traditional Chinese medicine during the decoction process. The insoluble components in the decoction are mostly in the form of nanoparticles, which can improve the problem of poor water solubility. However, the transfer rate of these insoluble components in the decoction is still very low, which limits the efficacy of the drug. This study aimed to refine the traditional decoction self-assembly phenomenon. The self-assembled nanoparticles were constructed by micro-precipitation method (MP-SAN), and characterized by particle size, zeta potential, stability index and morphology. The formation of MP-SAN and alterations in related physicochemical properties were evaluated using modern spectroscopic and thermal analysis techniques. The quality value transmitting pattern of lignan components within the MP-SAN was assessed
3.Comparison of the efficacy of TiRobot orthopaedic robot assisted F screw technique and inverted triangle parallel nail internal fixation in the treatment of unstable femoral neck fractures
Xing-Long ZHAO ; Jian-Jun SHEN ; Kang-Hu FENG ; Zhi-Wei CHEN ; Yuan-Long SI ; Xuan ZHANG ; Guan-De WANG ; Xiang HAI
China Journal of Orthopaedics and Traumatology 2024;37(2):129-134
Objective To compare the effectiveness of TiRobot assisted F screw technique and inverted triangle parallel nail internal fixation in the treatment of unstable femoral neck fractures.Methods A retrospective analysis was conducted on 72 patients with unstable femoral neck fractures who were treated with percutaneous cannulated screw fixation assisted with TiRobot Orthopaedic robot from December 2019 to April 2021.Among them,37 patients were treated with F screw internal fixa-tion,including 16 males and 21 females,aged47 to 64years old with an average of(53.87±5.28)years old;According to Pauwels classification,there were 1 case of type Ⅰ,19 cases of type Ⅱ,17 cases of type Ⅲ;8 cases of combined medical diseases;17 cases of falling,8 cases of traffic accident and 12 cases of falling from height;The time from injury to operation was 29 to 49 hours with average of(35.00±7.34)hours.Another 35 cases used internal fixation with an inverted triangle parallel nail,including 13 males and 22 females with an average age of 46 to 63 years old(52.36±5.05)years old;According to the Pauwels injury classifi-cation:there were 2 cases of type Ⅰ,21 cases of type Ⅱ,12 cases of type Ⅲ;6 cases of medical diseases,15 cases of falling in-jury,9 cases of traffic accident,11 cases of falling injury;The time from injury to operation was 30 to 45 hours with an average of(33.00±6.83)h.The intraoperative blood loss,operation time,intraoperative fluoroscopy times,follow-up time,fracture healing time,postoperative complications were observed and compared between the two groups.The hip joint function was e-valuated by Harris score at 6 months and 12 months after operation.Results There was no significant difference in operation time,intraoperative blood loss,intraoperative fluoroscopy times and other intraoperative data between two groups(P>0.05).Both groups were followed up regularly,and the follow-up time was 12 to 16 months.The fracture healing time and Harris score of the F screw internal fixation group were better than those of the inverted triangle parallel nail internal fixation group(P<0.05).There was 1 case of femoral neck shortening in the F screw internal fixation group,1 case of nonunion,1 case of nail withdrawal,and 1 case of lower extremity deep vein thrombosis in the inverted triangle internal fixation group.The incidence of complications in the F screw internal fixation group was lower than that in the inverted triangle parallel nail internal fixation group(P<0.05).Conclusion Percutaneous cannulated F screw technique using Tirobot navigation positioning system is a safe and effective treatment for patients with unstable femoral neck fractures.It can significantly shorten the fracture healing time,reduce the incidence of postoperative complications,significantly improve hip joint function,and improve the quality of life.
4.Historical evolution and modern research on co-production and processing method of "solid-liquid excipients".
Wei SUN ; Yu SHEN ; Ling-Yun ZHONG ; Xi-de YE ; Hong-Tao ZHANG ; Yue QIN ; Shao-Jiang LIU ; Wan-Long ZHANG
China Journal of Chinese Materia Medica 2024;49(22):6066-6072
"Solid-liquid excipients" co-production is one of the typical processing methods of excipients used from ancient times to the present day, and is widely applied in various processing schools and regional specialty varieties. This method significantly reduces the toxicity of traditional Chinese medicine(TCM), moderates medicinal properties, and enhances clinical efficacy. However, modern scientific research has given it limited attention, and many co-production methods of "solid-liquid excipients" have not been applied in production and practice. This paper reviewed the historical development of "solid-liquid excipients" co-production, outlined modern processing standards and methods in different processing schools, and further elaborated on the purposes and effects of this co-production method. This study is expected to provide references and evidence for further in-depth research, inheritance, innovation, and practical application.
Chemistry, Pharmaceutical/history*
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Drug Compounding/methods*
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Drugs, Chinese Herbal/chemistry*
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Excipients/chemistry*
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History, 20th Century
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History, 21st Century
;
History, Ancient
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Medicine, Chinese Traditional/history*
6.Preliminary study of TRPV4 affects chondrocyte degeneration.
Xue SHEN ; Hu ZHANG ; De-Ta CHEN ; Yue-Long CAO
China Journal of Orthopaedics and Traumatology 2023;36(10):990-995
OBJECTIVE:
To explore and verify that transient receptor potential vanilloid 4(TRPV4) affects chondrocyte degeneration.
METHODS:
Neonatal SD rats were selected, primary chondrocytes were extracted, and identified by toluidine blue staining and alcian blue staining;an in vitro chondrocyte inflammation model was constructed by IL-1β, and TRPV4 inhibitor was used to treat chondrocytes under inflammatory conditions, and the chondrocytes were treated by RT-PCR method was used to detect matrix metallopeptidase 13(MMP-13), a disintegrin and metalloproteinase with thrombospondin 5, (ADAMTS-5)、nitric oxide synthase 2(NOS2)、Collagen, type II alpha 1(Col2α1)and aggrecan (Acan) mRNA in chondrocytes; primary chondrocytes were treated with different concentrations of TRPV4 overexpression plasmid, and the optimal overexpression dose was screened. The mRNA expressions of TRPV4, MMP-13, ADAMTS-5, NOS2, Col2α1 and Acan in chondrocytes under the optimal TRPV4 overexpression dose were detected.
RESULTS:
Toluidine blue staining and Alcian blue staining identified the extracted cells as primary chondrocytes;RT-PCR showed that TRPV4, MMP-13, ADAMTS-5, NOS2 mRNA in chondrocytes treated with TRPV4 inhibitor under inflammatory conditions. The expression of Col2α1 mRNA was significantly decreased (P<0.05), and the expression of Col2α1 mRNA was increased (P<0.05). Although there was no significant difference in the expression of Acan mRNA, the overall trend was also increasing. The expression of Col2α1 and Acan mRNA in chondrocytes was significantly decreased (P<0.05), and the expression of NOS2 mRNA was increased(P<0.05), but there was no significant difference in MMP-13 and ADAMTS-5 (P>0.05).
CONCLUSION
Inhibiting the expression of TRPV4 can down-regulate the expression of genes related to chondrocyte degeneration.
Animals
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Rats
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Aggrecans/metabolism*
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Cartilage, Articular
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Cells, Cultured
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Chondrocytes
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Interleukin-1beta/metabolism*
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Matrix Metalloproteinase 13/metabolism*
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Rats, Sprague-Dawley
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RNA, Messenger/metabolism*
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TRPV Cation Channels/metabolism*
7.Active components and mechanism of Jinwugutong Capsules in treatment of osteoporosis: a study based on UPLC-Q-Exactive-MS/MS combined with network pharmacology.
Xiao-Shuang YANG ; Xin-Li SONG ; Xue-Li SONG ; Ying-Yong YANG ; Wen LIU ; Sheng-Lei YANG ; Jia-Nan SHI ; Li SHEN ; Kai-Long WAN ; Xing-de LIU
China Journal of Chinese Materia Medica 2023;48(12):3360-3372
UPLC-Q-Exactive-MS/MS and network pharmacology were employed to preliminarily study the active components and mechanism of Jinwugutong Capsules in the treatment of osteoporosis. Firstly, UPLC-Q-Exactive-MS/MS was employed to characterize the chemical components of Jinwugutong Capsules, and network pharmacology was employed to establish the "drug-component-target-pathway-disease" network. The key targets and main active components were thus obtained. Secondly, AutoDock was used for the molecular docking between the main active components and key targets. Finally, the animal model of osteoporosis was established, and the effect of Jinwugutong Capsules on the expression of key targets including RAC-alpha serine/threonine-protein kinase(AKT1), albumin(ALB), and tumor necrosis factor-alpha(TNF-α) was determined by enzyme-linked immunosorbent assay(ELISA). A total of 59 chemical components were identified from Jinwugutong Capsules, among which coryfolin, 8-prenylnaringenin, demethoxycurcumin, isobavachin, and genistein may be the main active components of Jinwugutong Capsules in treating osteoporosis. The topological analysis of the protein-protein interaction(PPI) network revealed 10 core targets such as AKT1, ALB, catenin beta 1(CTNNB1), TNF, and epidermal growth factor receptor(EGFR). The Kyoto Encyclopedia of Genes and Genomes(KEGG) enrichment showed that Jinwugutong Capsules mainly exerted the therapeutic effect by regulating the phosphatidylinositol 3-kinase(PI3K)/protein kinase B(AKT) signaling pathway, neuroactive ligand-receptor interaction, mitogen-activated protein kinase(MAPK) signaling pathway, Rap1 signaling pathway and so on. Molecular docking showed that the main active components of Jinwugutong Capsules well bound to the key targets. ELISA results showed that Jinwugutong Capsules down-regulated the protein levels of AKT1 and TNF-α and up-regulated the protein level of ALB, which preliminarily verified the reliability of network pharmacology. This study indicates that Jinwugutong Capsules may play a role in the treatment of osteoporosis through multiple components, targets, and pathways, which can provide reference for the further research.
Animals
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Tumor Necrosis Factor-alpha/genetics*
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Network Pharmacology
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Capsules
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Molecular Docking Simulation
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Phosphatidylinositol 3-Kinases
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Reproducibility of Results
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Tandem Mass Spectrometry
8.Preparation and in vitro release of quercetin nanocrystals self-stabilized Pickering emulsion.
Zhe WANG ; Fei HU ; Zhi-Hui CHE ; Qing SONG ; Bao-de SHEN ; Hai-Long YUAN
China Journal of Chinese Materia Medica 2022;47(5):1230-1236
A new quercetin nanocrystals self-stabilized Pickering emulsion(QT-NSSPE) was prepared by high-pressure homogenization combined with probe ultrasonic method. The influences of oil fraction, quercetin(QT) concentration, and pH of water phase on the formation of QT-NSSPE were investigated. On this basis, the QT-NSSPE prepared under optimal conditions was evaluated in terms of microstructure, stability, and in vitro release and the droplet size and drug loading were 15.82 μm and 4.87 mg·mL~(-1), respectively. The shell structure formed by quercetin nanocrystals(QT-NC) on the emulsion droplet surface was observed under a scanning electron microscope(SEM). X-ray diffraction(XRD) showed that the crystallinity of adsorbed QT-NC decreased significantly as compared with the raw QT. There were not significant changes of QT-NSSPE properties after 30 days of storage at room temperature. The in vitro release experiment confirmed that QT-NSSPE has a higher accumulative release rate than the raw QT. All these results indicated that QT-NSSPE has a great stability and a satisfactory in vitro release behavior, which is a promising new oral delivery system for QT.
Emulsions/chemistry*
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Nanoparticles
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Particle Size
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Quercetin
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Water/chemistry*
9.A multicenter epidemiological study of acute bacterial meningitis in children.
Cai Yun WANG ; Hong Mei XU ; Jiao TIAN ; Si Qi HONG ; Gang LIU ; Si Xuan WANG ; Feng GAO ; Jing LIU ; Fu Rong LIU ; Hui YU ; Xia WU ; Bi Quan CHEN ; Fang Fang SHEN ; Guo ZHENG ; Jie YU ; Min SHU ; Lu LIU ; Li Jun DU ; Pei LI ; Zhi Wei XU ; Meng Quan ZHU ; Li Su HUANG ; He Yu HUANG ; Hai Bo LI ; Yuan Yuan HUANG ; Dong WANG ; Fang WU ; Song Ting BAI ; Jing Jing TANG ; Qing Wen SHAN ; Lian Cheng LAN ; Chun Hui ZHU ; Yan XIONG ; Jian Mei TIAN ; Jia Hui WU ; Jian Hua HAO ; Hui Ya ZHAO ; Ai Wei LIN ; Shuang Shuang SONG ; Dao Jiong LIN ; Qiong Hua ZHOU ; Yu Ping GUO ; Jin Zhun WU ; Xiao Qing YANG ; Xin Hua ZHANG ; Ying GUO ; Qing CAO ; Li Juan LUO ; Zhong Bin TAO ; Wen Kai YANG ; Yong Kang ZHOU ; Yuan CHEN ; Li Jie FENG ; Guo Long ZHU ; Yan Hong ZHANG ; Ping XUE ; Xiao Qin LI ; Zheng Zhen TANG ; De Hui ZHANG ; Xue Wen SU ; Zheng Hai QU ; Ying ZHANG ; Shi Yong ZHAO ; Zheng Hong QI ; Lin PANG ; Cai Ying WANG ; Hui Ling DENG ; Xing Lou LIU ; Ying Hu CHEN ; Sainan SHU
Chinese Journal of Pediatrics 2022;60(10):1045-1053
Objective: To analyze the clinical epidemiological characteristics including composition of pathogens , clinical characteristics, and disease prognosis acute bacterial meningitis (ABM) in Chinese children. Methods: A retrospective analysis was performed on the clinical and laboratory data of 1 610 children <15 years of age with ABM in 33 tertiary hospitals in China from January 2019 to December 2020. Patients were divided into different groups according to age,<28 days group, 28 days to <3 months group, 3 months to <1 year group, 1-<5 years of age group, 5-<15 years of age group; etiology confirmed group and clinically diagnosed group according to etiology diagnosis. Non-numeric variables were analyzed with the Chi-square test or Fisher's exact test, while non-normal distrituction numeric variables were compared with nonparametric test. Results: Among 1 610 children with ABM, 955 were male and 650 were female (5 cases were not provided with gender information), and the age of onset was 1.5 (0.5, 5.5) months. There were 588 cases age from <28 days, 462 cases age from 28 days to <3 months, 302 cases age from 3 months to <1 year of age group, 156 cases in the 1-<5 years of age and 101 cases in the 5-<15 years of age. The detection rates were 38.8% (95/245) and 31.5% (70/222) of Escherichia coli and 27.8% (68/245) and 35.1% (78/222) of Streptococcus agalactiae in infants younger than 28 days of age and 28 days to 3 months of age; the detection rates of Streptococcus pneumonia, Escherichia coli, and Streptococcus agalactiae were 34.3% (61/178), 14.0% (25/178) and 13.5% (24/178) in the 3 months of age to <1 year of age group; the dominant pathogens were Streptococcus pneumoniae and the detection rate were 67.9% (74/109) and 44.4% (16/36) in the 1-<5 years of age and 5-<15 years of age . There were 9.7% (19/195) strains of Escherichia coli producing ultra-broad-spectrum β-lactamases. The positive rates of cerebrospinal fluid (CSF) culture and blood culture were 32.2% (515/1 598) and 25.0% (400/1 598), while 38.2% (126/330)and 25.3% (21/83) in CSF metagenomics next generation sequencing and Streptococcus pneumoniae antigen detection. There were 4.3% (32/790) cases of which CSF white blood cell counts were normal in etiology confirmed group. Among 1 610 children with ABM, main intracranial imaging complications were subdural effusion and (or) empyema in 349 cases (21.7%), hydrocephalus in 233 cases (14.5%), brain abscess in 178 cases (11.1%), and other cerebrovascular diseases, including encephalomalacia, cerebral infarction, and encephalatrophy, in 174 cases (10.8%). Among the 166 cases (10.3%) with unfavorable outcome, 32 cases (2.0%) died among whom 24 cases died before 1 year of age, and 37 cases (2.3%) had recurrence among whom 25 cases had recurrence within 3 weeks. The incidences of subdural effusion and (or) empyema, brain abscess and ependymitis in the etiology confirmed group were significantly higher than those in the clinically diagnosed group (26.2% (207/790) vs. 17.3% (142/820), 13.0% (103/790) vs. 9.1% (75/820), 4.6% (36/790) vs. 2.7% (22/820), χ2=18.71, 6.20, 4.07, all P<0.05), but there was no significant difference in the unfavorable outcomes, mortility, and recurrence between these 2 groups (all P>0.05). Conclusions: The onset age of ABM in children is usually within 1 year of age, especially <3 months. The common pathogens in infants <3 months of age are Escherichia coli and Streptococcus agalactiae, and the dominant pathogen in infant ≥3 months is Streptococcus pneumoniae. Subdural effusion and (or) empyema and hydrocephalus are common complications. ABM should not be excluded even if CSF white blood cell counts is within normal range. Standardized bacteriological examination should be paid more attention to increase the pathogenic detection rate. Non-culture CSF detection methods may facilitate the pathogenic diagnosis.
Adolescent
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Brain Abscess
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Child
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Child, Preschool
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Escherichia coli
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Female
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Humans
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Hydrocephalus
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Infant
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Infant, Newborn
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Male
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Meningitis, Bacterial/epidemiology*
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Retrospective Studies
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Streptococcus agalactiae
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Streptococcus pneumoniae
;
Subdural Effusion
;
beta-Lactamases
10.Quantitative Pulmonary Administration of Essential Oil from Alpiniae Zerumbet Fructus for Treatment of Emphysema
Zi-min CAI ; Jian-qing PENG ; Yi CHEN ; Di PAN ; Yan-yan ZHANG ; Ling TAO ; Xiang-chun SHEN ; Qing-de LONG
Chinese Journal of Experimental Traditional Medical Formulae 2022;28(3):91-97
ObjectiveTo investigate the effect of quantitative pulmonary administration of the essential oil from Alpiniae Zerumbet Fructus (EOAZF) on porcine pancreatic elastase (PPE)-induced emphysema in mice and explore its action mechanism. MethodC57BL/6J mice were randomly divided into five group, namely the control group, model group, low- (2 mg·kg-1) and high-dose (20 mg·kg-1) EOFAZ groups, and positive control dexamethasone (DEX,1 mg·kg-1) group. The mice were treated with pulmonary administration of PPE using a microsprayer aerosolizer, once every seven days, for four times in total, for inducing emphysema. During this period, EOFAZ were administered with a quantitative microsprayer aerosolizer once every other day, for 14 times. The lung tissues were then sampled and stained with hematoxylin-eosin (HE) for observing the morphological changes and calculating the pulmonary mean linear intercept (MLI). The concentrations of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6) in the plasma were determined by enzyme-linked immunosorbent assay (ELISA). The activities of superoxide dismutase (SOD) and catalase (CAT) and the content of malondialdehyde (MDA) in the lung tissues were measured using the biochemical assay kits. The protein expression levels of nuclear factor E2-related factor 2 (Nrf2), quinone oxidoreductase1 (NQO1), B cell lymphoma-2 (Bcl-2)-associated X protein (Bax), and Bcl-2 in lung tissues were detected by Western blot. ResultThe results of lung morphological observation and MLI detection showed that compared with the control group, the model group showed obvious inflammatory infiltration, alveolar enlargement and fusion, and increased MLI (P<0.05). Compared with the model group, EOFAZ effectively alleviated the pathological changes such as alveolar dilatation, pulmonary inflammatory cell infiltration, and lung cell apoptosis caused by PPE, and decreased the MLI (P<0.05). As revealed by ELISA, the inflammatory level of mice in the model group increased significantly (P<0.01), while the TNF-α, IL-1β, and IL-6 levels in the plasma were decreased after quantitative administration of EOFAZ (P<0.01). Compared with the control group, the model group exhibited significantly enhanced oxidative stress (P<0.01). After treatment with EOFAZ by quantitative administration, the activities of SOD and CAT in the lung tissue were increased (P<0.01) and the content of MDA was decreased (P<0.01). Western blot results demonstrated that the apoptosis-related protein expression in the model group was increased significantly as compared with that in the control group (P<0.01), whereas the expression levels of antioxidant stress proteins Nrf2 and NQO1 declined (P<0.05). The relative protein expression of apoptosis-related proteins Bax/Bcl-2 in the EOFAZ groups was lower than that in the model group (P<0.01), while the expression of antioxidant stress proteins Nrf2 and NQO1 was higher (P<0.05). ConclusionQuantitative pulmonary administration of EOFAZ effectively alleviates the inflammation and oxidative stress, reduces lung cell apoptosis, and hinders the occurrence and development of emphysema. Its antioxidant mechanism is closely related to the up-regulation of Nrf2 and its downstream NQO1.

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