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1.
Mol Cell Biochem ; 2024 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-38997506

RESUMEN

Dietary salt is increasingly recognized as an independent risk factor for cognitive impairment. However, the exact mechanisms are not yet fully understood. Mitochondria, which play a crucial role in energy metabolism, are implicated in cognitive function through processes such as mitochondrial dynamics and mitophagy. While mitochondrial dysfunction is acknowledged as a significant determinant of cognitive function, the specific relationship between salt-induced cognitive impairment and mitochondrial health has yet to be fully elucidated. Here, we explored the underlying mechanism of cognitive impairment of mice and N2a cells treated with high-salt focusing on the mitochondrial homeostasis with western blotting, immunofluorescence, electron microscopy, RNA sequencing, and more. We further explored the potential role of SIRT3 in salt-induced mitochondrial dysfunction and synaptic alteration through plasmid transfection and siRNA. High salt diet significantly inhibited mitochondrial fission and blocked mitophagy, leading to dysfunctional mitochondria and impaired synaptic plasticity. Our findings demonstrated that SIRT3 not only promote mitochondrial fission by modulating phosphorylated DRP1, but also rescue mitophagy through promoting PINK1/Parkin-dependent pathway. Overall, our data for the first time indicate that mitochondrial homeostasis imbalance is a driver of impaired synaptic plasticity in a cognitive impairment phenotype that is exacerbated by a long-term high-salt diet, and highlight the protective role of SIRT3 in this process.

2.
Metab Brain Dis ; 39(5): 803-819, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38771412

RESUMEN

A high-salt diet (HSD) has been associated with various health issues, including hypertension and cardiovascular diseases. However, recent studies have revealed a potential link between high salt intake and cognitive impairment. This study aims to investigate the effects of high salt intake on autophagy, tau protein hyperphosphorylation, and synaptic function and their potential associations with cognitive impairment. To explore these mechanisms, 8-month-old male C57BL/6 mice were fed either a normal diet (0.4% NaCl) or an HSD (8% NaCl) for 3 months, and Neuro-2a cells were incubated with normal medium or NaCl medium (80 mM). Behavioral tests revealed learning and memory deficits in mice fed the HSD. We further discovered that the HSD decreased autophagy, as indicated by diminished levels of the autophagy-associated proteins Beclin-1 and LC3, along with an elevated p62 protein level. HSD feeding significantly decreased insulin-like growth factor-1 receptor (IGF1R) expression in the brain of C57BL/6 mice and activated mechanistic target of rapamycin (mTOR) signaling. In addition, the HSD reduced synaptophysin and postsynaptic density protein 95 (PSD95) expression in the hippocampus and caused synaptic loss in mice. We also found amyloid ß accumulation and hyperphosphorylation of tau protein at different loci both in vivo and in vitro. Overall, this study highlights the clinical significance of understanding the impact of an HSD on cognitive function. By targeting the IGF1R/mTOR/p70S6K pathway or promoting autophagy, it may be possible to mitigate the negative effects of high salt intake on cognitive function.


Asunto(s)
Disfunción Cognitiva , Ratones Endogámicos C57BL , Receptor IGF Tipo 1 , Proteínas Quinasas S6 Ribosómicas 70-kDa , Transducción de Señal , Cloruro de Sodio Dietético , Serina-Treonina Quinasas TOR , Animales , Masculino , Serina-Treonina Quinasas TOR/metabolismo , Disfunción Cognitiva/metabolismo , Disfunción Cognitiva/inducido químicamente , Disfunción Cognitiva/etiología , Proteínas Quinasas S6 Ribosómicas 70-kDa/metabolismo , Ratones , Transducción de Señal/efectos de los fármacos , Cloruro de Sodio Dietético/efectos adversos , Receptor IGF Tipo 1/metabolismo , Proteínas tau/metabolismo , Autofagia/efectos de los fármacos , Hipocampo/metabolismo , Hipocampo/efectos de los fármacos
3.
Phytother Res ; 38(5): 2128-2153, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38400575

RESUMEN

Thrombotic disorders, such as myocardial infarction and stroke, are the leading cause of death in the global population and have become a health problem worldwide. Drug therapy is one of the main antithrombotic strategies, but antithrombotic drugs are not completely safe, especially the risk of bleeding at therapeutic doses. Recently, natural products have received widespread interest due to their significant efficacy and high safety, and an increasing number of studies have demonstrated their antithrombotic activity. In this review, articles from databases, such as Web of Science, PubMed, and China National Knowledge Infrastructure, were filtered and the relevant information was extracted according to predefined criteria. As a result, more than 100 natural products with significant antithrombotic activity were identified, including flavonoids, phenylpropanoids, quinones, terpenoids, steroids, and alkaloids. These compounds exert antithrombotic effects by inhibiting platelet activation, suppressing the coagulation cascade, and promoting fibrinolysis. In addition, several natural products also inhibit thrombosis by regulating miRNA expression, anti-inflammatory, and other pathways. This review systematically summarizes the natural products with antithrombotic activity, including their therapeutic effects, mechanisms, and clinical applications, aiming to provide a reference for the development of new antithrombotic drugs.


Asunto(s)
Productos Biológicos , Fibrinolíticos , Trombosis , Productos Biológicos/farmacología , Productos Biológicos/uso terapéutico , Humanos , Trombosis/tratamiento farmacológico , Fibrinolíticos/farmacología , Fibrinolíticos/uso terapéutico , Animales , Activación Plaquetaria/efectos de los fármacos , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico
4.
Inflammopharmacology ; 32(3): 1743-1757, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38568399

RESUMEN

Inflammation can be triggered by any factor. The primary pathological manifestations can be summarized as the deterioration, exudation, and proliferation of local tissues, which can cause systemic damage in severe cases. Inflammatory lesions are primarily localized but may interact with body systems to cause provocative storms, parenchymal organ lesions, vascular and central nervous system necrosis, and other pathologic responses. Tetrandrine (TET) is a bisbenzylquinoline alkaloid extracted from the traditional Chinese herbal medicine Stephania tetrandra, which has been shown to have significant efficacy in inflammatory conditions such as rheumatoid arthritis, hepatitis, nephritis, etc., through NF-κB, MAPK, ERK, and STAT3 signaling pathways. TET can regulate the body's imbalanced metabolic pathways, reverse the inflammatory process, reduce other pathological damage caused by inflammation, and prevent the vicious cycle. More importantly, TET does not disrupt body's normal immune function while clearing the body's inflammatory state. Therefore, it is necessary to pay attention to its dosage and duration during treatment to avoid unexpected side effects caused by a long half-life. In summary, TET has a promising future in treating inflammatory diseases. The author reviews current therapeutic studies of TET in inflammatory conditions to provide some ideas for subsequent anti-inflammatory studies of TET.


Asunto(s)
Bencilisoquinolinas , Inflamación , Bencilisoquinolinas/farmacología , Bencilisoquinolinas/uso terapéutico , Humanos , Animales , Inflamación/tratamiento farmacológico , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Transducción de Señal/efectos de los fármacos
5.
Mol Med ; 29(1): 86, 2023 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-37400752

RESUMEN

BACKGROUND: Osteoarthritis (OA) is a degenerative joint disease with lacking effective prevention targets. A disintegrin and metalloproteinase with thrombospondin motifs 12 (ADAMTS12) is a member of the ADAMTS family and is upregulated in OA pathologic tissues with no fully understood molecular mechanisms. METHODS: The anterior cruciate ligament transection (ACL-T) method was used to establish rat OA models, and interleukin-1 beta (IL-1ß) was administered to induce rat chondrocyte inflammation. Cartilage damage was analyzed via hematoxylin-eosin, Periodic Acid-Schiff, safranin O-fast green, Osteoarthritis Research Society International score, and micro-computed tomography assays. Chondrocyte apoptosis was detected by flow cytometry and TdT dUTP nick-end labeling. Signal transducer and activator of transcription 1 (STAT1), ADAMTS12, and methyltransferase-like 3 (METTL3) levels were detected by immunohistochemistry, quantitative polymerase chain reaction (qPCR), western blot, or immunofluorescence assay. The binding ability was confirmed by chromatin immunoprecipitation-qPCR, electromobility shift assay, dual-luciferase reporter, or RNA immunoprecipitation (RIP) assay. The methylation level of STAT1 was analyzed by MeRIP-qPCR assay. STAT1 stability was investigated by actinomycin D assay. RESULTS: The STAT1 and ADAMTS12 expressions were significantly increased in the human and rat samples of cartilage injury, as well as in IL-1ß-treated rat chondrocytes. STAT1 is bound to the promoter region of ADAMTS12 to activate its transcription. METTL3/ Insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2) mediated N6-methyladenosine modification of STAT1 promoted STAT1 mRNA stability, resulting in increased expression. ADAMTS12 expression was reduced and the IL-1ß-induced inflammatory chondrocyte injury was attenuated by silencing METTL3. Additionally, knocking down METTL3 in ACL-T-produced OA rats reduced ADAMTS12 expression in their cartilage tissues, thereby alleviating cartilage damage. CONCLUSION: METTL3/IGF2BP2 axis increases STAT1 stability and expression to promote OA progression by up-regulating ADAMTS12 expression.


Asunto(s)
MicroARNs , Osteoartritis , Ratas , Humanos , Animales , Osteoartritis/metabolismo , Microtomografía por Rayos X , Células Cultivadas , Cartílago/metabolismo , Condrocitos/metabolismo , Interleucina-1beta/metabolismo , MicroARNs/metabolismo , Apoptosis , Proteínas ADAMTS/genética , Proteínas ADAMTS/metabolismo , Metiltransferasas/metabolismo , Proteínas de Unión al ARN/metabolismo
6.
Anal Bioanal Chem ; 415(17): 3503-3513, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37199792

RESUMEN

Bear bile powder (BBP) is a valuable animal-derived product with a huge adulteration problem on market. It is a crucially important task to identify BBP and its counterfeit. Electronic sensory technologies are the inheritance and development of traditional empirical identification. Considering that each drug has its own specific odor and taste characteristics, electronic tongue (E-tongue), electronic nose (E-nose) and GC-MS were used to evaluate the aroma and taste of BBP and its common counterfeit. Two active components of BBP, namely tauroursodeoxycholic acid (TUDCA) and taurochenodeoxycholic acid (TCDCA) were measured and linked with the electronic sensory data. The results showed that bitterness was the main flavor of TUDCA in BBP, saltiness and umami were the main flavor of TCDCA. The volatiles detected by E-nose and GC-MS were mainly aldehydes, ketones, alcohols, hydrocarbons, carboxylic acids, heterocyclic, lipids, and amines, mainly earthy, musty, coffee, bitter almond, burnt, pungent odor descriptions. Four different machine learning algorithms (backpropagation neural network, support vector machine, K-nearest neighbor, and random forest) were used to identify BBP and its counterfeit, and the regression performance of these four algorithms was also evaluated. For qualitative identification, the algorithm of random forest has shown the best performance, with 100% accuracy, precision, recall and F1-score. Also, the random forest algorithm has the best R2 and the lowest RMSE in terms of quantitative prediction.


Asunto(s)
Nariz Electrónica , Ursidae , Animales , Polvos , Bilis , Lengua
7.
Anal Bioanal Chem ; 415(2): 345-356, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36350342

RESUMEN

Bear bile powder (BBP) is one of the most famous traditional Chinese medicines derived from animals. It has a long history of medicinal use and is widely used in the treatment of hepatobiliary and ophthalmic diseases. Due to its similar morphological characterizations and chemical composition compared with other bile powders, it is difficult to accurately identify its authenticity. In addition, there are very few methods that could analyze the geographical origins of BBP. In this study, elemental analysis isotope ratio mass spectrometry (EA-IRMS) and inductively coupled plasma mass spectrometry (ICP-MS) were used to determine stable isotope ratios and elemental contents, respectively. Combined these variables with chemometrics, the discrimination models were established successfully for identifying the authenticity and geographical origins of BBP. Meanwhile, the discrimination markers were identified by calculating the variable importance for the projection (VIP) value of each variable. A total of 13 discrimination markers (δ13C, δ15N, C, Li, Mg, K, Ca, Cr, Ni, Zn, As, Se, and Sr) were used to further establish the fingerprint of BBP. According to similarity analysis, the authenticity and geographical origins of BBP could be identified without chemometrics. In conclusion, the present study established a reliable method for authenticity identification and origin traceability of BBP, which will provide references for the quality control of bile medicines.


Asunto(s)
Ursidae , Animales , Polvos , Bilis , Isótopos/química , Espectrometría de Masas/métodos
8.
Chem Biodivers ; 20(3): e202201109, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36760194

RESUMEN

Bear bile powder (BBP) is a rare animal-derived traditional Chinese medicine, and it has been widely used to treat visual disorders and hepatobiliary diseases in East Asia. However, there is still a lack of reliable quality control methods for BBP. This study was designed to establish a comprehensive quality map of BBP based on bile acids. High-performance liquid chromatography coupled with charged aerosol detector (HPLC-CAD) was used for fingerprint establishment and quantitative analysis of BBP. The similarities of HPLC-CAD chromatograms for 50 batches of BBP were more than 0.95, while the similarities of reference chromatograms between 6 other animal bile and BBP were low than 0.7. Additionally, five bile acids in BBP, including tauroursodeoxycholic acid, taurocholic acid, taurochenodeoxycholic acid, ursodesoxycholic acid, and chenodeoxycholic acid, were simultaneously quantified. This method has been validated with good regression as well as satisfactory precision, sensitivity, stability, repeatability, and accuracy. Using this method, the contents of five bile acids in BBP samples from five producing areas were determined and compared. Furthermore, Fisher linear discriminant analysis was performed to discriminate the geographic origins of BBP. The result demonstrated that HPLC-CAD fingerprint combined with multi-components quantification is an effective and reliable method for quality control of BBP, it could be a meaningful reference for the quality evaluation of medicinal bile.


Asunto(s)
Medicamentos Herbarios Chinos , Ursidae , Animales , Bilis/química , Ácidos y Sales Biliares/análisis , Quimiometría , Cromatografía Líquida de Alta Presión/métodos , Medicamentos Herbarios Chinos/química , Polvos/análisis , Ursidae/metabolismo
9.
Molecules ; 28(11)2023 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-37298829

RESUMEN

Due to the presence of physiological barriers, it is difficult to achieve the desired therapeutic efficacy of drugs; thus, it is necessary to develop an efficient drug delivery system that enables advanced functions such as self-monitoring. Curcumin (CUR) is a naturally functional polyphenol whose effectiveness is limited by poor solubility and low bioavailability, and its natural fluorescent properties are often overlooked. Therefore, we aimed to improve the antitumor activity and drug uptake monitoring by simultaneously delivering CUR and 5-Fluorouracil (5-FU) in the form of liposomes. In this study, dual drug-loaded liposomes (FC-DP-Lip) encapsulating CUR and 5-FU were prepared by the thin-film hydration method; their physicochemical properties were characterized; and their biosafety, drug uptake distribution in vivo, and tumor cell toxicity were evaluated. The results showed that the nanoliposome FC-DP-Lip showed good morphology, stability, and drug encapsulation efficiency. It showed good biocompatibility, with no side effects on zebrafish embryonic development. In vivo uptake in zebrafish showed that FC-DP-Lip has a long circulation time and presents gastrointestinal accumulation. In addition, FC-DP-Lip was cytotoxic against a variety of cancer cells. This work showed that FC-DP-Lip nanoliposomes can enhance the toxicity of 5-FU to cancer cells, demonstrating safety and efficiency, and enabling real-time self-monitoring functions.


Asunto(s)
Antineoplásicos , Curcumina , Nanopartículas , Animales , Curcumina/farmacología , Curcumina/química , Liposomas/química , Fluorouracilo/farmacología , Pez Cebra , Antineoplásicos/farmacología , Antineoplásicos/química , Tamaño de la Partícula , Nanopartículas/química
10.
Phytother Res ; 36(1): 336-364, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34818697

RESUMEN

Andrographis paniculata (Burm. f.) Wall. ex Nees, a renowned herb medicine in China, is broadly utilized in traditional Chinese medicine (TCM) for the treatment of cold and fever, sore throat, sore tongue, snake bite with its excellent functions of clearing heat and toxin, cooling blood and detumescence from times immemorial. Modern pharmacological research corroborates that andrographolide, the major ingredient in this traditional herb, is the fundamental material basis for its efficacy. As the main component of Andrographis paniculata (Burm. f.) Wall. ex Nees, andrographolide reveals numerous therapeutic actions, such as antiinflammatory, antioxidant, anticancer, antimicrobial, antihyperglycemic and so on. However, there are scarcely systematic summaries on the specific mechanism of disease treatment and pharmacokinetics. Moreover, it is also found that it possesses easily ignored security issues in clinical application, such as nephrotoxicity and reproductive toxicity. Thereby it should be kept a lookout over in clinical. Besides, the relationship between the efficacy and security issues of andrographolide should be investigated and evaluated scientifically. In this review, special emphasis is given to andrographolide, a multifunctional natural terpenoids, including its pharmacology, pharmacokinetics, toxicity and pharmaceutical researches. A brief overview of its clinical trials is also presented. This review intends to systematically and comprehensively summarize the current researches of andrographolide, which is of great significance for the development of andrographolide clinical products. Noteworthy, those un-cracked issues such as specific pharmacological mechanisms, security issues, as well as the bottleneck in clinical transformation, which detailed exploration and excavation are still not to be ignored before achieving integration into clinical practice. In addition, given that current extensive clinical data do not have sufficient rigor and documented details, more high-quality investigations in this field are needed to validate the efficacy and/or safety of many herbal products.


Asunto(s)
Diterpenos , Plantas Medicinales , Andrographis paniculata , Diterpenos/farmacología , Extractos Vegetales
11.
J Environ Sci (China) ; 111: 185-196, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34949348

RESUMEN

Black carbon (BC) plays an important role in air quality and climate change, which is closely associated with its mixing state and chemical compositions. In this work the mixing state of BC-containing single particles was investigated to explore the evolution process of ambient BC particles using a single particle aerosol mass spectrometer (SPAMS) in March 2018 in Zhengzhou, China. The BC-containing particles accounted for 61.4% of total detected ambient single particles and were classified into five types including BC-nitrate (BC-N, 52.3%) as the most abundant species, followed by BC-nitrate-sulfate (BC-NS, 22.4%), BCOC (16.8%), BC-fresh (BC-F, 4.5%) and BC-sulfate particles (BC-S, 4.0%). With enhancement of the ambient nitrate concentration, the relative peak area (RPA) of nitrate in BC-N and BCNS particles both increased, yet only the number fraction (Nf) of BCN particles increased while the Nf of BC-NS particles decreased, suggesting that the enhanced mixing state of BC with nitrate was mainly due to the increase in the ambient nitrate mass concentration. In addition, the Nf of BC-N decreased from 65.3% to 28.4% as the absorbing Ångström exponents (AAE) of eBC increased from 0.75 to 1.45, which indicated the reduction of light absorption ability of aged BC particles with the enhanced formation of BC-N particles. The results of this work indicated a change in the mixing state of BC particles due to the dominance of nitrate in PM2.5, which also influenced the optical properties of aged BC particles.


Asunto(s)
Contaminantes Atmosféricos , Nitratos , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Carbono/análisis , China , Monitoreo del Ambiente , Nitratos/análisis , Tamaño de la Partícula , Material Particulado/análisis
12.
J Environ Sci (China) ; 108: 44-57, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34465436

RESUMEN

Zhengzhou is one of the most haze-polluted cities in Central China with high organic carbon emission, which accounts for 15%-20% of particulate matter (PM2.5) in winter and causes significantly adverse health effects. Volatile organic compounds (VOCs) are the precursors of secondary PM2.5 and O3 formation. An investigation of characteristics, sources and health risks assessment of VOCs was carried out at the urban area of Zhengzhou from 1st to 31st December, 2019. The mean concentrations of total detected VOCs were 48.8 ± 23.0 ppbv. Alkanes (22.0 ± 10.4 ppbv), halocarbons (8.1 ± 3.9 ppbv) and aromatics (6.5 ± 3.9 ppbv) were the predominant VOC species, followed by alkenes (5.1 ± 3.3 ppbv), oxygenated VOCs (3.6 ± 1.8 ppbv), alkyne (3.5 ± 1.9, ppbv) and sulfide (0.5 ± 0.9 ppbv). The Positive Matrix Factorization model was used to identify and apportion VOCs sources. Five major sources of VOCs were identified as vehicular exhaust, industrial processes, combustion, fuel evaporation, and solvent use. The carcinogenic and non-carcinogenic risk values of species were calculated. The carcinogenic and non-carcinogenic risks of almost all air toxics increased during haze days. The total non-carcinogenic risks exceeded the acceptable ranges. Most VOC species posed no non-carcinogenic risk during three haze events. The carcinogenic risks of chloroform, 1,2-dichloroethane, 1,2-dibromoethane, benzyl chloride, hexachloro-1,3-butadiene, benzene and naphthalene were above the acceptable level (1.0  ×  10-6) but below the tolerable risk level (1.0  ×  10-4). Industrial emission was the major contributor to non-carcinogenic, and solvent use was the major contributor to carcinogenic risks.


Asunto(s)
Contaminantes Atmosféricos , Ozono , Compuestos Orgánicos Volátiles , Contaminantes Atmosféricos/análisis , China , Monitoreo del Ambiente , Ozono/análisis , Estaciones del Año , Compuestos Orgánicos Volátiles/análisis
13.
J Environ Sci (China) ; 84: 80-96, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31284919

RESUMEN

Central Plains region of China, represented by Henan Province, is facing serious air pollution problems. Vehicular exhaust emissions had adverse impacts on the atmospheric environment. The first comprehensive and novel vehicle emission inventory for Henan Province using vehicle kilometers traveled, localized emission factors, and activity data at city-level was developed. Furthermore, 3 km × 3 km gridded emission and temporal variations were determined by using localized information. Results show that the total emissions of sulfur dioxide (SO2), nitrogen oxides (NOx), carbon monoxide (CO), particular matter with aerodynamic diameter < 10 µm (PM10), aerodynamic diameter < 2.5 µm (PM2.5), volatile organic compounds (VOCs), VOCs-evaporation and ammonia in 2015 were 9.1, 533.4, 1190.7, 23.7, 21.6, 150.8, 31.5 and 10.4 Gg, respectively, and the emission intensities of the above pollutants were 0.05, 2.7, 6.0, 0.1, 0.1, 0.8, 0.2 and 0.05 g/km, respectively. Vehicles meeting the Primary China 1, China 3 and China 4 contributed 89.1%, 82.7%, 75.3%, 75.5%, 75.5%, 68.2%, 68.4% and 82.3% for SO2, NOx, CO, PM10, PM2.5, VOCs, VOCs-evaporation and ammonia emissions, respectively. Zhengzhou, Zhoukou, Nanyang, Luoyang, Shangqiu and Xinyang showed relatively higher emissions and contributed more than 50% of each pollutant. The spatial distribution indicated obvious characteristics of the road network, and high-level emission was concentrated in the downtown areas. Additionally, the ozone formation potential (OFP) based on the estimated speciated VOC emissions was 569.6 Gg in Henan Province. Aliphatic and aromatic hydrocarbons were the main species of VOCs, whereas olefins contributed the largest proportion of OFP, with 42.2%.


Asunto(s)
Contaminantes Atmosféricos , Contaminación por Tráfico Vehicular/estadística & datos numéricos , Emisiones de Vehículos , China , Ciudades/estadística & datos numéricos , Ozono , Compuestos Orgánicos Volátiles
15.
Huan Jing Ke Xue ; 45(7): 3849-3857, 2024 Jul 08.
Artículo en Zh | MEDLINE | ID: mdl-39022933

RESUMEN

The Air Pollution Prevention and Control Action Plan (APPCAP) was promulgated in China in 2013. To explore the effectiveness of APPCAP on PM2.5 in winter in Zhengzhou, PM2.5 samples were collected in Zhengzhou Monitoring Center during December 2013 and December 2018. The chemical composition of PM2.5 was analyzed, including EC, OC, water soluble ions, and metal elements. Pollution episodes under different stages were selected to investigate the changes in PM2.5 concentration and composition. The results showed that: ① The average concentration of PM2.5 in winter in Zhengzhou decreased from (215.38 ±107.28) µg·m-3 in 2013 to (77.45 ±49.81) µg·m-3 in 2018, with a decrease rate of 64%. ② The concentrations of EC, K+, SO42-, and Cl- decreased by 85%, 80%, 78%, and 72%, respectively, and the decrease rate in OC, NH4+, and NO3- was 50%, 41%, and 32%, respectively. ③ Compared with those in winter of 2013, the ratios of OC/EC in winter of 2018 increased by 2.6 times, and the proportion of secondary organic carbon in OC increased to 57%; meanwhile, values of sulfur oxidation rate and nitrogen oxidation rate increased by 1.5 and 1.0 times, respectively, indicating heavy secondary pollution in Zhengzhou. ④ The mass ratios of NO3-/SO42-increased from 0.8 ±0.2 in 2013 to 2.5 ±1.0 in 2018, indicating that the contribution of mobile sources increased and surpassed fixed sources as the main source in Zhengzhou. ⑤The comparison results of different stages of the heavy pollution process showed that ρ(PM2.5) decreased significantly in 2018 compared with that in 2013, with the peak concentration decreasing by 61%. The main chemical composition changed from OC, NO3-, SO42-, and NH4+ to OC, NO3-, and NH4+. The results indicated that the primary emission source control in Zhengzhou had achieved remarkable effects, but the contribution of secondary generation to PM2.5 showed an elevated trend; thus, the influence of secondary generation requires further attention in the future.

16.
Huan Jing Ke Xue ; 45(1): 36-47, 2024 Jan 08.
Artículo en Zh | MEDLINE | ID: mdl-38216456

RESUMEN

Nitrate (NO3-), sulfate (SO42-), and ammonium (NH4+) are important components of PM2.5, and studying their characteristics and influencing factors is essential for the continuous improvement of air quality. A series of online instruments were used to analyze the chemical components of PM2.5 in Zhengzhou in the summer of 2020. The results showed that the average ρ(PM2.5) was (28 ±13) µg·m-3, showing a daily variation characteristic of high at night and low during the day. The main concentrations of NO3-, SO42-, and NH4+ were (7.8 ±6.7), (7.2 ±3.7), and (5.5 ±3.1) µg·m-3, accounting for 22%, 21%, and 16% in PM2.5, respectively. The proportions of NO3- (27%) and SO42- (23%) in PM2.5, respectively, increased with the increase in PM2.5 and O3 concentration. In addition, the proportions of NO3- and NH4+ increased under low wind speed, high humidity, low temperature, and rainfall conditions. Moreover, the proportion of NO3- showed a daily variation characteristic of high at night and low during the day, whereas the opposite was true for SO42-. The gas-particle partitioning process of NH4NO3 was the main factor affecting the concentrations of NO3- and NH4+ in PM2.5. Low temperature, high humidity, and high aerosol water content concentrations favored the partitioning of HNO3 and NH3 to the particulate phase. High pH also favored the partitioning of gas-phase HNO3 to NO3-; however, it was not conducive to the partition of NH3 to NH4+. These trends partially explained the increase in the concentration and proportion of NO3- in PM2.5 under different scenarios.

17.
ACS Appl Mater Interfaces ; 16(21): 27741-27749, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38745362

RESUMEN

The introduction of hydrophobic side chain structures in anion exchange membranes (AEMs) to facilitate ion transport has been widely studied; however, low or moderate hydrophobic hydrocarbon and semifluorinated side chains are insufficient to induce a high degree of microphase separation. Herein, we design and prepare poly(aryl piperidinium) AEMs with completely methylene-free perfluorinated side chains, which can maximize the thermodynamic incompatibility between main- and side chains, thus enhancing microphase separation at medium ion exchange capacities (IECs). According to the molecular dynamics study, the methylene-free perfluorinated side chain leads to better hydration of cations. The hydroxide conductivity of the methylene-free perfluorinated side chain-grafted PAP-pF-1 membrane reaches 124.9 mS cm-1 at 80 °C, and the PAP-sF-1 with semifluorinated side chains and PAP-CH-1 with hydrocarbon side chains show lower conductivity (116.8 and 104.0 mS cm-1). The H2/O2 fuel cell using the PAP-pF-1 membrane demonstrates a remarkable peak power density (1651 mW cm-2 at 80 °C) and durability (greater than 300 h). This work provides a novel insight into enhancing microphase separation in AEMs; it opens up new possibilities for developing high-performance AEMs.

18.
J Biomed Res ; 38(2): 122-136, 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38403286

RESUMEN

Aging is characterized by progressive degeneration of tissues and organs, and it is positively associated with an increased mortality rate. The brain, as one of the most significantly affected organs, experiences age-related changes, including abnormal neuronal activity, dysfunctional calcium homeostasis, dysregulated mitochondrial function, and increased levels of reactive oxygen species. These changes collectively contribute to cognitive deterioration. Aging is also a key risk factor for neurodegenerative diseases, such as Alzheimer's disease and Parkinson's disease. For many years, neurodegenerative disease investigations have primarily focused on neurons, with less attention given to microglial cells. However, recently, microglial homeostasis has emerged as an important mediator in neurological disease pathogenesis. Here, we provide an overview of brain aging from the perspective of the microglia. In doing so, we present the current knowledge on the correlation between brain aging and the microglia, summarize recent progress of investigations about the microglia in normal aging, Alzheimer's disease, Parkinson's disease, Huntington's disease, and amyotrophic lateral sclerosis, and then discuss the correlation between the senescent microglia and the brain, which will culminate with a presentation of the molecular complexity involved in the microglia in brain aging with suggestions for healthy aging.

19.
Exp Neurol ; 371: 114591, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37898395

RESUMEN

AIMS: Recent evidence suggests an association between a high-fat diet (HFD) and cognitive decline. HFD may reduce synaptic plasticity and cause tau hyperphosphorylation, but the mechanisms involved remain unclear. The purpose of this study was to explore whether Sirtuin1 (SIRT1)/AMP-activated protein kinase (AMPK) pathway was involved in this pathogenic effect in the HFD exposed mice. METHODS: C57BL/6 mice at 12 months of age were fed a standard (9% kcal fat) or high-fat (60% kcal fat) diet for 22 weeks, and Neuro-2a (N2a) cells were treated with normal culture medium or a palmitic acid (PA) medium (100uM) for 40 h. After that, cognitive function was tested by Morris water maze (MWM). The levels of proteins involved in SIRT1/AMPK pathway and autophagy were measured using western blotting and immunofluorescence. We also assessed the phosphorylation of tau protein and synapse. RESULTS: The mice presented impaired learning and memory abilities. We further found decreased levels of synaptophysin (Syn) and brain-derived neurotrophic factor (BDNF), increased tau46 and phosphorylated tau protein, and damaged neurons in mice after HFD or in N2a cells treated with PA medium. Moreover, HFD can also reduce the expression of SIRT1, inhibit AMPK phosphorylation, and block autophagic flow in both mice and cells. After treating the cells with the SIRT1 agonist SRT1720, SIRT1/AMPK pathway and autophagy-related proteins were partially reversed and the number of PA-induced positive cells was alleviated in senescence-associated ß-galactosidase (SA-ß-gal) staining. CONCLUSIONS: HFD may inhibit the expression of SIRT1/AMPK pathway and disrupt autophagy flux, and result in tau hyperphosphorylation and synaptic dysfunction during aging, which ultimately lead to cognitive decline.


Asunto(s)
Disfunción Cognitiva , Dieta Alta en Grasa , Ratones , Animales , Dieta Alta en Grasa/efectos adversos , Proteínas Quinasas Activadas por AMP/metabolismo , Proteínas tau/farmacología , Sirtuina 1/metabolismo , Ratones Endogámicos C57BL , Disfunción Cognitiva/etiología , Autofagia
20.
Front Aging Neurosci ; 16: 1340117, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38435399

RESUMEN

Age-related cognitive impairment represents a significant health concern, with the understanding of its underlying mechanisms and potential interventions being of paramount importance. This study aimed to investigate the effects of hyperbaric oxygen therapy (HBOT) on cognitive function and neuronal integrity in aged (22-month-old) C57BL/6 mice. Male mice were exposed to HBOT for 2 weeks, and spatial learning and memory abilities were assessed using the Morris water maze. We employed transcriptome sequencing and Gene Ontology (GO) term enrichment analysis to examine the effects of HBOT on gene expression profiles, with particular attention given to synapse-related genes. Our data indicated a significant upregulation of postsynapse organization, synapse organization, and axonogenesis GO terms, likely contributing to improved cognitive performance. Moreover, the hyperphosphorylation of tau, a hallmark of many neurodegenerative diseases, was significantly reduced in the HBO-treated group, both in vivo and in vitro. Transmission electron microscopy revealed significant ultrastructural alterations in the hippocampus of the HBOT group, including an increase in the number of synapses and the size of the active zone, a reduction in demyelinated lesions, and a decreased number of "PANTHOS." Furthermore, Western blot analyses confirmed the upregulation of PSD95, BDNF, and Syn proteins, suggesting enhanced synaptic plasticity and neurotrophic support. Moreover, HBOT increased autophagy, as evidenced by the elevated levels of Beclin-1 and LC3 proteins and the reduced level of p62 protein. Finally, we demonstrated that HBOT activated the AMPK-mTOR signaling pathway, a critical regulator of autophagy. Notably, our findings provide novel insights into the mechanisms by which HBOT ameliorates age-related cognitive impairment, suggesting the potential therapeutic value of this approach.

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