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1.
J Cell Mol Med ; 28(12): e18494, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38890797

RESUMO

Stress triggers a comprehensive pathophysiological cascade in organisms. However, there is a substantial gap in the research regarding the effects of stress on liver function. This study aimed to investigate the impact of restraint stress on hepatocellular damage and elucidate the underlying molecular mechanisms. An effective mouse restraint stress model was successfully developed, and liver function analysis was performed using laser speckle imaging, metabolomics and serum testing. Alterations in hepatocyte morphology were assessed using haematoxylin and eosin staining and transmission electron microscopy. Oxidative stress in hepatocytes was assessed using lipid reactive oxygen species and malondialdehyde. The methylation status and expression of GSTP1 were analysed using DNA sequencing and, real-time PCR, and the expression levels of GPX4, TF and Nrf2 were evaluated using real-time quantitative PCR, western blotting, and immunohistochemical staining. A stress-induced model was established in vitro by using dexamethasone-treated AML-12 cells. To investigate the underlying mechanisms, GSTP1 overexpression, small interfering RNA, ferroptosis and Nrf2 inhibitors were used. GSTP1 methylation contributes to stress-induced hepatocellular damage and dysfunction. GSTP1 is involved in ferroptosis-mediated hepatocellular injury induced by restraint stress via the TF/Nrf2 pathway. These findings suggest that stress-induced hepatocellular injury is associated with ferroptosis, which is regulated by TF/Nrf2/GSTP1.

2.
Appl Microbiol Biotechnol ; 108(1): 343, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38789572

RESUMO

Isolates of Vibrio splendidus are ubiquitously presented in various marine environments, and they can infect diverse marine culture animals, leading to high mortality and economic loss. Therefore, a control strategy of the infection caused by V. splendidus is urgently recommended. Tryptanthrin is a naturally extracted bioactive chemical with antimicrobial activity to other bacteria. In this study, the effects of tryptanthrin on the bacterial growth and virulence-related factors of one pathogenic strain V. splendidus AJ01 were determined. Tryptanthrin (10 µg/mL) could completely inhibit the growth of V. splendidus AJ01. The virulence-related factors of V. splendidus AJ01 were affected in the presence of tryptanthrin. Tryptanthrin resulted an increase in biofilm formation, but lead to reduction in the motility and hemolytic activity of V. splendidus cells. In the cells treated with tryptanthrin, two distinctly differentially expressed extracellular proteins, proteases and flagellum, were identified using SDS-PAGE combined with LC-MS. Real-time reverse transcriptase PCR confirmed that the genes involved in the flagellar formation and hemolysin decreased, whereas specific extracellular proteases and the genes involved in the biofilm formation were upregulated. Two previously annotated luxOVs genes were cloned, and their expression levels were analyzed at different cell densities. Molecular docking was performed to predict the interaction between LuxOVs and ATP/tryptanthrin. The two sigma-54-dependent transcriptional regulators showed similar ATP or tryptanthrin binding capacity but with different sites, and the direct competitive binding between ATP and tryptanthrin was present only in their binding to LuxO1. These results indicated that tryptanthrin can be used as a bactericide of V. splendidus by inhibiting the growth, bacterial flagella, and extracellular proteases, but increasing the biofilm. Sigma-54-dependent transcriptional regulator, especially the quorum sensing regulatory protein LuxO1, was determined to be the potential target of tryptanthrin. KEY POINTS: • Tryptanthrin inhibited the growth of V. splendidus in a dose-dependent manner. • The effect of tryptanthrin on the virulence factors of V. splendidus was characterized. • LuxO was the potential target for tryptanthrin based on molecular docking.


Assuntos
Antibacterianos , Biofilmes , Quinazolinas , Vibrio , Fatores de Virulência , Biofilmes/efeitos dos fármacos , Vibrio/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Quinazolinas/farmacologia , Quinazolinas/química , Fatores de Virulência/genética , Simulação de Acoplamento Molecular , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Flagelos/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Animais , Testes de Sensibilidade Microbiana , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos
3.
Lipids Health Dis ; 23(1): 68, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38431645

RESUMO

BACKGROUND: Stress is implicated in various pathological conditions leading to liver injury. Existing evidence suggests that excessive stress can induce mitochondrial damage in hepatocytes, yet the underlying mechanism remains unclear. Ceramide synthase 6 (CerS6)-derived C16:0 ceramide is recognised as a lipotoxic substance capable of causing mitochondrial damage. However, the role of CerS6 in stress has received insufficient attention. This study aimed to explore the involvement of CerS6 in stress-induced hepatic damage and its associated mechanisms. METHODS: The rat restraint stress model and a corticosterone (CORT)-induced hepatocyte stress model were employed for in vivo and in vitro experimental analyses, respectively. Changes in mitochondrial damage and ceramide metabolism in hepatocytes induced by stress were evaluated. The impact of CORT on mitochondrial damage and ceramide metabolism in hepatocytes was assessed following CerS6 knockdown. Mitochondria were isolated using a commercial kit, and ceramides in liver tissue and hepatocytes were detected by LC-MS/MS. RESULTS: In comparison to the control group, rats subjected to one week of restraint exhibited elevated serum CORT levels. The liver displayed significant signs of mitochondrial damage, accompanied by increased CerS6 and mitochondrial C16:0 ceramide, along with activation of the AMPK/p38 MAPK pathway. In vitro studies demonstrated that CORT treatment of hepatocytes resulted in mitochondrial damage, concomitant with elevated CerS6 and mitochondrial C16:0 ceramide. Furthermore, CORT induced sequential phosphorylation of AMPK and p38 MAPK proteins, and inhibition of the p38 MAPK pathway using SB203580 mitigated the CORT-induced elevation in CerS6 protein. Knocking down CerS6 in hepatocytes inhibited both the increase in C16:0 ceramide and the release of mitochondrial cytochrome c induced by CORT. CONCLUSIONS: CerS6-associated C16:0 ceramide plays a mediating role in stress-induced mitochondrial damage in hepatocytes. The molecular mechanism is linked to CORT-induced activation of the AMPK/p38 MAPK pathway, leading to upregulated CerS6.


Assuntos
Proteínas Quinases Ativadas por AMP , Espectrometria de Massas em Tandem , Ratos , Animais , Proteínas Quinases Ativadas por AMP/metabolismo , Cromatografia Líquida , Ceramidas/metabolismo , Hepatócitos/metabolismo , Fígado/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Apoptose , Esfingosina N-Aciltransferase/genética , Esfingosina N-Aciltransferase/metabolismo
4.
Int J Mol Sci ; 25(15)2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39125645

RESUMO

Stress-induced alterations in central neuron metabolism and function are crucial contributors to depression onset. However, the metabolic dysfunctions of the neurons associated with depression and specific molecular mechanisms remain unclear. This study initially analyzed the relationship between cholesterol and depression using the NHANES database. We then induced depressive-like behaviors in mice via restraint stress. Applying bioinformatics, pathology, and molecular biology, we observed the pathological characteristics of brain cholesterol homeostasis and investigated the regulatory mechanisms of brain cholesterol metabolism disorders. Through the NHANES database, we initially confirmed a significant correlation between cholesterol metabolism abnormalities and depression. Furthermore, based on successful stress mouse model establishment, we discovered the number of cholesterol-related DEGs significantly increased in the brain due to stress, and exhibited regional heterogeneity. Further investigation of the frontal cortex, a brain region closely related to depression, revealed stress caused significant disruption to key genes related to cholesterol metabolism, including HMGCR, CYP46A1, ACAT1, APOE, ABCA1, and LDLR, leading to an increase in total cholesterol content and a significant decrease in synaptic proteins PSD-95 and SYN. This indicates cholesterol metabolism affects neuronal synaptic plasticity and is associated with stress-induced depressive-like behavior in mice. Adeno-associated virus interference with NR3C1 in the prefrontal cortex of mice subjected to short-term stress resulted in reduced protein levels of NRIP1, NR1H2, ABCA1, and total cholesterol content. At the same time, it increased synaptic proteins PSD95 and SYN, effectively alleviating depressive-like behavior. Therefore, these results suggest that short-term stress may induce cholesterol metabolism disorders by activating the NR3C1/NRIP1/NR1H2 signaling pathway. This impairs neuronal synaptic plasticity and consequently participates in depressive-like behavior in mice. These findings suggest that abnormal cholesterol metabolism in the brain induced by stress is a significant contributor to depression onset.


Assuntos
Colesterol , Depressão , Lobo Frontal , Estresse Psicológico , Animais , Masculino , Camundongos , Colesterol/metabolismo , Depressão/metabolismo , Depressão/etiologia , Modelos Animais de Doenças , Lobo Frontal/metabolismo , Metabolismo dos Lipídeos , Camundongos Endogâmicos C57BL , Estresse Psicológico/metabolismo
5.
Int J Mol Sci ; 25(5)2024 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-38474189

RESUMO

Coronary artery spasm (CAS) plays an important role in the pathogeneses of various ischemic heart diseases and has gradually become a common cause of life-threatening arrhythmia. The specific molecular mechanism of CAS has not been fully elucidated, nor are there any specific diagnostic markers for the condition. Therefore, this study aimed to examine the specific molecular mechanism underlying CAS, and screen for potential diagnostic markers. To this end, we successfully constructed a rat CAS model and achieved in vitro culture of a human coronary-artery smooth-muscle cell (hCASMC) contraction model. Possible molecular mechanisms by which protein kinase C (PKC) regulated CAS through the C kinase-potentiated protein phosphatase 1 inhibitor of 17 kDa (CPI-17)/myosin II regulatory light chain (MLC2) pathway were studied in vivo and in vitro to screen for potential molecular markers of CAS. We performed hematoxylin and eosin staining, myocardial zymogram, and transmission electron microscopy to determine myocardial and coronary artery injury in CAS rats. Then, using immunohistochemical staining, immunofluorescence staining, and Western blotting, we further demonstrated a potential molecular mechanism by which PKC regulated CAS via the CPI-17/MLC2 pathway. The results showed that membrane translocation of PKCα occurred in the coronary arteries of CAS rats. CPI-17/MLC2 signaling was observably activated in coronary arteries undergoing CAS. In addition, in vitro treatment of hCASMCs with angiotensin II (Ang II) increased PKCα membrane translocation while consistently activating CPI-17/MLC2 signaling. Conversely, GF-109203X and calphostin C, specific inhibitors of PKC, inactivated CPI-17/MLC2 signaling. We also collected the coronary artery tissues from deceased subjects suspected to have died of CAS and measured their levels of phosphorylated CPI-17 (p-CPI-17) and MLC2 (p-MLC2). Immunohistochemical staining was positive for p-CPI-17 and p-MLC2 in the tissues of these subjects. These findings suggest that PKCα induced CAS through the CPI-17/MLC2 pathway; therefore, p-CPI-17 and p-MLC2 could be used as potential markers for CAS. Our data provide novel evidence that therapeutic strategies against PKC or CPI-17/MLC2 signaling might be promising in the treatment of CAS.


Assuntos
Vasoespasmo Coronário , Animais , Humanos , Ratos , Biomarcadores/metabolismo , Morte Súbita Cardíaca , Fosfoproteínas/metabolismo , Fosforilação , Proteína Quinase C/metabolismo , Proteína Quinase C-alfa/metabolismo
6.
J Cell Mol Med ; 27(21): 3313-3325, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37593898

RESUMO

Mitochondria are sensitive organelles that sense intrinsic and extrinsic stressors and maintain cellular physiological functions through the dynamic homeostasis of mitochondrial fusion and fission. Numerous pathological processes are associated with mitochondrial fusion and fission disorders. However, the molecular mechanism by which stress induces cardiac pathophysiological changes through destabilising mitochondrial fusion and fission is unclear. Therefore, this study aimed to investigate whether the endoplasmic reticulum stress signalling pathway initiated by the turbulence of mitochondrial fusion and fission under stressful circumstances is involved in cardiomyocyte damage. Based on the successful establishment of the classical stress rat model of restraint plus ice water swimming, we measured the content of serum lactate dehydrogenase. We used haematoxylin-eosin staining, special histochemical staining, RT-qPCR and western blotting to clarify the cardiac pathology, ultrastructural changes and expression patterns of mitochondrial fusion and fission marker proteins and endoplasmic reticulum stress signalling pathway proteins. The results indicated that mitochondrial fusion and fission markers and proteins of the endoplasmic reticulum stress JNK signalling pathway showed significant abnormal dynamic changes with the prolongation of stress, and stabilisation of mitochondrial fusion and fission using Mdivi-1 could effectively improve these abnormal expressions and ameliorate cardiomyocyte injury. These findings suggest that stress could contribute to pathological cardiac injury, closely linked to the endoplasmic reticulum stress JNK signalling pathway induced by mitochondrial fusion and fission turbulence.


Assuntos
Dinâmica Mitocondrial , Miócitos Cardíacos , Ratos , Animais , Miócitos Cardíacos/metabolismo , Transdução de Sinais , Estresse do Retículo Endoplasmático/genética
7.
Microb Pathog ; 175: 105981, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36642286

RESUMO

Vibrio splendidus, a gram-negative bacterium that is ubiquitously present in marine environments, has been increasingly deemed an important opportunistic pathogen of marine animals. In this study, the biofilm formation of V. splendidus was quantitatively determined and morphologically characterized. Three stages of biofilm formation, including adhesion, aggregation and maturation were observed in the biofilm formed by V. splendidus. The inhibitory effect of exogenous bis (3',5')-cyclic dimeric guanosine monophosphate (c-di-GMP) on the biofilm formation from the scratch and preformed established biofilms of V. splendidus was determined. When 200 µmol/L c-di-GMP was added, the quantity of biofilm decreased by 88.1% or 66.7% under the two conditions. To explore the preliminary mechanism of exogenous c-di-GMP on the biofilm formed by V. splendidus, proteomic analysis was performed. GO enrichment analysis showed that exogenous c-di-GMP upregulated biological processes, including the tricarboxylic acid cycle, oxidation‒reduction reactions and organonitrogen compound catabolism and significantly downregulated tRNA threonylcarbamoyladenosine modification, protein dephosphorylation, and lactate transmembrane transporter activity. Sequence-specific DNA binding activity was the most markedly downregulated molecular function. KEGG analysis showed that the valine, leucine and isoleucine degradation pathway was the most enriched pathway, followed by nitrogen metabolism, among the 20 upregulated pathways. Among the downregulated pathways, a nonribosomal peptide structure pathway and the streptomycine, polyketide sugar unit, acarbose and validamycin biosynthesis pathways were significantly enriched. Our present study provides basic data for the biofilm formation of V. splendidus and the preliminary inhibitory mechanism of exogenous c-di-GMP on the biofilm formation of V. splendidus.


Assuntos
Proteômica , Vibrio cholerae , Vibrio cholerae/genética , GMP Cíclico/metabolismo , Biofilmes , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica
8.
PLoS Biol ; 18(8): e3000808, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32817651

RESUMO

Although dysregulation of mitochondrial dynamics has been linked to cellular senescence, which contributes to advanced age-related disorders, it is unclear how Krüppel-like factor 5 (Klf5), an essential transcriptional factor of cardiovascular remodeling, mediates the link between mitochondrial dynamics and vascular smooth muscle cell (VSMC) senescence. Here, we show that Klf5 down-regulation in VSMCs is correlated with rupture of abdominal aortic aneurysm (AAA), an age-related vascular disease. Mice lacking Klf5 in VSMCs exacerbate vascular senescence and progression of angiotensin II (Ang II)-induced AAA by facilitating reactive oxygen species (ROS) formation. Klf5 knockdown enhances, while Klf5 overexpression suppresses mitochondrial fission. Mechanistically, Klf5 activates eukaryotic translation initiation factor 5a (eIF5a) transcription through binding to the promoter of eIF5a, which in turn preserves mitochondrial integrity by interacting with mitofusin 1 (Mfn1). Accordingly, decreased expression of eIF5a elicited by Klf5 down-regulation leads to mitochondrial fission and excessive ROS production. Inhibition of mitochondrial fission decreases ROS production and VSMC senescence. Our studies provide a potential therapeutic target for age-related vascular disorders.


Assuntos
Aneurisma da Aorta Abdominal/genética , Células Endoteliais/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Mitocôndrias/metabolismo , Fatores de Iniciação de Peptídeos/genética , Proteínas de Ligação a RNA/genética , Idoso , Angiotensina II/genética , Angiotensina II/metabolismo , Angiotensina II/farmacologia , Animais , Aorta/diagnóstico por imagem , Aorta/metabolismo , Aorta/patologia , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/metabolismo , Aneurisma da Aorta Abdominal/patologia , Senescência Celular/efeitos dos fármacos , Ecocardiografia , Células Endoteliais/patologia , Feminino , GTP Fosfo-Hidrolases/genética , GTP Fosfo-Hidrolases/metabolismo , Humanos , Fatores de Transcrição Kruppel-Like/deficiência , Masculino , Camundongos , Camundongos Knockout , Mitocôndrias/patologia , Dinâmica Mitocondrial/efeitos dos fármacos , Fatores de Iniciação de Peptídeos/deficiência , Cultura Primária de Células , Regiões Promotoras Genéticas , Ligação Proteica , Espécies Reativas de Oxigênio/metabolismo , Fator de Iniciação de Tradução Eucariótico 5A
9.
Fish Shellfish Immunol ; 140: 108997, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37586599

RESUMO

Pacifastin proteins are previously found to regulate the phenoloxidase system in invertebrates and arthropods. In this study, the immune response that was regulated by Ajpacifastin-like in the sea cucumber Apostichopus japonicus was determined. RNA interference was used to knock down the expression of the Ajpacifastin-like gene in A. japonicus, followed by challenge with Vibrio splendidus, and the colony count showed that the survival of V. splendidus in the si-Ajpacifastin group increased 4.64-fold compared to that of the control group. The purified recombinant Ajpacifastin-like showed an inhibitory effect on the extracellular protease activity of the supernatant collected from the V. splendidus culture. Consequently, a comparative transcriptome analysis of the coelomocytes from the control group and the si-Ajpacifastin group was performed to explore the global regulatory effect of the Ajpacifastin-like. A total of 1486 differentially expressed genes (DEGs) were identified, including 745 upregulated genes and 741 downregulated genes. GO enrichment showed that the DEGs were mainly enriched in translation, cytosolic ribosomal subunit and structural constituent of ribosome. KEGG analysis showed that the DEGs were significantly enriched in the retinoic acid-inducible gene I (RIG-I)-like receptor signaling pathway, antigen processing and presentation, toll-like receptor signaling pathway, mitogen-activated protein kinase signaling pathway, nuclear factor-kappa B signaling pathway and other immune-related pathways. Furthermore, real-time reverse transcriptase PCR was used to determine the RNA levels of six DEGs, i.e., cathepsinB, CYLD, caspase8, TRAF6, hsp90 and FADD, to verify the RNA-seq results. Overall, our results specified the immune response and pathways of A. japonicus in which Ajpacifastin-like was involved in.


Assuntos
Pepinos-do-Mar , Stichopus , Vibrio , Animais , Stichopus/genética , Vibrio/fisiologia , Imunidade , Imunidade Inata/genética
10.
Int J Mol Sci ; 24(16)2023 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-37629166

RESUMO

The dorsomedial hypothalamus nucleus (DMH) is an important component of the autonomic nervous system and plays a critical role in regulating the sympathetic outputs of the heart. Stress alters the neuronal activity of the DMH, affecting sympathetic outputs and triggering heart rate variability. However, the specific molecular mechanisms behind stress leading to abnormal DMH neuronal activity have still not been fully elucidated. Therefore, in the present study, we successfully constructed a stressed rat model and used it to investigate the potential molecular mechanisms by which IL-6 regulates GABAA receptors in the DMH through activation of the JAK/STAT pathway and thus affects heart rate variability in rats. By detecting the c-Fos expression of neurons in the DMH and electrocardiogram (ECG) changes in rats, we clarified the relationship between abnormal DMH neuronal activity and heart rate variability in stressed rats. Then, using ELISA, immunohistochemical staining, Western blotting, RT-qPCR, and RNAscope, we further explored the correlation between the IL-6/JAK/STAT signaling pathway and GABAA receptors. The data showed that an increase in IL-6 induced by stress inhibited GABAA receptors in DMH neurons by activating the JAK/STAT signaling pathway, while specific inhibition of the JAK/STAT signaling pathway using AG490 obviously reduced DMH neuronal activity and improved heart rate variability in rats. These findings suggest that IL-6 regulates the expression of GABAA receptors via the activation of the JAK/STAT pathway in the DMH, which may be an important cause of heart rate variability in stressed rats.


Assuntos
Interleucina-6 , Receptores de GABA-A , Animais , Ratos , Frequência Cardíaca , Interleucina-6/genética , Janus Quinases , Fatores de Transcrição STAT , Transdução de Sinais , Hipotálamo
11.
Int J Legal Med ; 136(5): 1303-1307, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35394178

RESUMO

Formaldehyde is a colourless irritating gas at room temperature, which, therefore, is usually stored in liquid form. This compound is often used as an antiseptic, disinfectant and fumigant in biology and medicine. Formaldehyde, as a potential carcinogen confirmed by the World Health Organization (WHO), is seriously harmful to human systems, such as the respiratory system, immune system and reproductive system. This article reports a case of a 50-year-old woman who died after accidentally drinking 25% formaldehyde solution in a transparent plastic bottle. Anatomical examination revealed fixed tissue morphology of the stomach and adjacent organs. The toxicity test results showed that the concentrations of formaldehyde in the blood and gastric tissue were 36.56 mg/kg and 274.48 mg/kg, respectively, which was consistent with death from formaldehyde poisoning. Due to the particular smell of formaldehyde, poisoning by accidentally drinking formaldehyde solution is rare. Of late, the mechanism of death from formaldehyde poisoning is that it rapidly causes coagulation of tissue cell protein, which may lose its normal function. Based on the pathological characteristics of the case, we put forward a new viewpoint on the mechanism of death from formaldehyde poisoning in which formaldehyde causes rapid fixation of blood in the tissue, thus leading to acute circulatory disturbance.


Assuntos
Formaldeído , Intoxicação , Acidentes , Feminino , Formaldeído/efeitos adversos , Humanos , Pessoa de Meia-Idade , Intoxicação/patologia , Hipersensibilidade Respiratória , Estômago/patologia
12.
Phys Chem Chem Phys ; 24(23): 14424-14429, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35648431

RESUMO

We innovatively used a polypropylene (PP) separator as a substrate and PEO-LiTFSI-SN as a paste to coat on both of the PP surfaces, and formed a sandwich-like solid polymer electrolyte (SPE). The SPE shows a conductivity of 4.22 × 10-3 S cm-1 at room temperature and 7.75 × 10-5 S cm-1 at 0 °C. The pyrene-4,5,9,10-tetraone (PTO)||SPE||Li battery shows a maximum discharge specific capacity of 187.8 mA h g-1 at a current density of 20 mA g-1 under 0 °C. After 100 cycles, the capacity could still be obtained at 88.4 mA h g-1, and the coulombic efficiency stayed stable at 98%. This work paved a new way for the development of solid-state organic batteries (SSOBs) at low temperatures.

13.
Sensors (Basel) ; 22(3)2022 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-35161974

RESUMO

This study experimentally investigated the effects of hydrogen direct injection on combustion and the cycle-by-cycle variations in a spark ignition n-butanol engine under lean burn conditions. For this purpose, a spark ignition engine installed with a hydrogen and n-butanol dual fuel injection system was specially developed. Experiments were conducted at four excess air ratios, four hydrogen fractions(φ(𝐻2)) and pure n-butanol. Engine speed and intake manifold absolute pressure (MAP) were kept at 1500 r/min and 43 kPa, respectively. The results indicate that the θ0-10 and θ10-90 decreased gradually with the increase in hydrogen fraction. Additionally, the indicated mean effective pressure (IMEP), the peak cylinder pressure (Pmax) and the maximum rate of pressure rise ((dP/dφ)max) increased gradually, while their cycle-by-cycle variations decreased with the increase in hydrogen fraction. In addition, the correlation between the (dP/dφ)max and its corresponding crank angle became weak with the increase in the excess air coefficient (λ), which tends to be strongly correlated with the increase in hydrogen fraction. The coefficient of variation of the Pmax and the IMEP increased with the increase in λ, while they decreased obviously after blending in the hydrogen under lean burn conditions. Furthermore, when λ was 1.0, a 5% hydrogen fraction improved the cycle-by-cycle variations most significantly. While a larger hydrogen fraction is needed to achieve the excellent combustion characteristics under lean burn conditions, hydrogen direct injection can promote combustion process and is beneficial for enhancing stable combustion and reducing the cycle-by-cycle variations.

14.
Fish Shellfish Immunol ; 97: 108-113, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31830571

RESUMO

Polian vesicles are considered as the site of coelomocyte formation, and play crucial roles in the inflammatory reaction in sea cucumber. After evisceration, coelomocytes and internal organs except polian vesicles are excreted. Our previous study found that the total number of coelomocytes was rapidly recovered at 6 h post-evisceration in sea cucumber Apostichopus japonicus, and this regeneration of coelomocytes might be closely related to polian vesicles. To further investigate the related-gene expression pattern of the polian vesicles at 6 h post-evisceration, the transcriptome analysis of polian vesicles was carried out. A total of 2752 differentially expressed genes (DEGs) were identified, including 1,453 up-regulated genes and 1299 down-regulated genes. Gene Ontology (GO) enrichment showed that most of the DEGs were classified under Regulation of transcription, Regulation of RNA metabolic process, Regulation of nucleic acid-templated transcription. Meanwhile, 11 significantly enriched Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were identified. Among them, Wnt, TGF-ß and Endocytosis pathways are well-related with cell proliferation and differentiation, which may be involved in the regeneration of coelomocytes in A. japonicus after evisceration. In addition, FoxO signaling pathway plays important roles in immunoregulation, in which the expression levels of the DEGs were significantly up-regulated, inferring that polian vesicles could not only participate in the coelomocyte regeneration process, but also undertake a certain immune defense function in A. japonicus after evisceration. These findings will be beneficial for understanding the mechanisms of coelomocyte regeneration and immune defense of A. japonicus after evisceration.


Assuntos
Perfilação da Expressão Gênica , Transdução de Sinais/imunologia , Stichopus/anatomia & histologia , Stichopus/genética , Animais , Proliferação de Células , Redes e Vias Metabólicas , Stichopus/imunologia
15.
Int J Mol Sci ; 20(2)2019 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-30634592

RESUMO

The ventral tegmental area (VTA), a critical portion of the mesencephalic dopamine system, is thought to be involved in the development and maintenance of addiction. It has been proposed that the dopaminergic regulatory factors TH, Nurr1, and Pitx3 are crucial for determining the survival and maintenance of dopaminergic neurons. Thus, the present study investigated whether abnormalities in these dopaminergic regulatory factors in the VTA were associated with neuronal injury induced by chronic morphine dependence. Rat models with different durations of morphine dependence were established. Thionine staining was used to observe morphological changes in the VTA neurons. Immunohistochemistry and western blot were used to observe changes in the expression of the dopaminergic regulatory proteins TH, Nurr1, and Pitx3. Thionine staining revealed that prolonged morphine dependence resulted in dopaminergic neurons with edema, a lack of Nissl bodies, and pyknosis. Immunohistochemistry showed that the number of TH⁺, Nurr1⁺, and Pitx3⁺ cells, and the number of TH⁺ cells expressing Nurr1 or Pitx3, significantly decreased in the VTA after a long period of morphine dependence. Western blot results were consistent with the immunohistochemistry findings. Chronic morphine exposure resulted in abnormalities in dopaminergic regulatory factors and pathological changes in dopaminergic neurons in the VTA. These results suggest that dysregulation of dopaminergic regulatory factors in the VTA are associated with neuronal injury induced by chronic morphine dependence.


Assuntos
Neurônios Dopaminérgicos/metabolismo , Proteínas de Homeodomínio/metabolismo , Dependência de Morfina/metabolismo , Dependência de Morfina/patologia , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo , Área Tegmentar Ventral/metabolismo , Área Tegmentar Ventral/patologia , Animais , Expressão Gênica , Proteínas de Homeodomínio/genética , Imuno-Histoquímica , Masculino , Dependência de Morfina/genética , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Ratos , Fatores de Transcrição/genética , Tirosina 3-Mono-Oxigenase/genética
16.
Front Med (Lausanne) ; 11: 1441032, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39139790

RESUMO

Background: Light chain (AL) amyloidosis stands as the most prevalent subtype of systemic amyloidosis, encompassing a group of rare diseases. Here, we evaluated the scientific landscape of AL amyloidosis to investigate research trends and identify hotspots within the field. Methods: Relevant studies on AL amyloidosis published over the past two decades were retrieved from the Web of Science Core Collection. The publications between 2005 and 2024 were subjected to bibliometric analyses, leveraging tools including CiteSpace, VOSviewer, RStudio and MS Excel to analyse and visualize the annual publication trend, co-occurrence patterns, collaborative networks among countries, organizations, and authors. Burst keywords and references were also examined to obtain the research history, and emerging hotspots. Results: The bibliometric analysis included 2,864 articles published between 2005 and 2024. The most productive journal is Amyloid-Journal of Protein Folding Disorders. The United States, along with several developed nations, emerges as a dominant force in international AL amyloidosis research. "AL amyloidosis" and "cardiac amyloidosis" were the primary hotspots over the past two decades, and "Biomarkers," "Cardiac amyloidosis," and "treatment" would be future trends. Conclusion: This bibliometric analysis examined the research developments in AL amyloidosis over the past two decades using bibliometric software. Recent research in this field primarily focuses on two main areas: clinical diagnosis and treatment of AL amyloidosis, as well as cardiac amyloidosis. Emphasis is placed on understanding the mechanisms underlying immunoglobulin light chain aggregation and deposition to mitigate organ involvement.

17.
Sci Rep ; 14(1): 13543, 2024 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-38866996

RESUMO

The objective of this study was to investigate spleen pathology and immune cell subset alterations in mice exposed to acute and chronic restraint stress over various timeframes. A deeper understanding of stress-induced spleen injuries can provide new insights into the mechanisms underlying stress-induced disorders. C57BL/6N mice were restrained for different durations (1, 3, 7, 14 and 21 days) for 6-8 h daily. The control mice were observed at the same time points. Post restraint, behavioural experiments were conducted to assess spleen weight, gross morphology and microscopic histological changes. Immunohistochemical staining was used to detect changes in glucocorticoid receptor (GR) expression, immune cell subsets and cell proliferation in response to stress. Our analysis revealed significant behavioural abnormalities in the stressed mice. In particular, there was an increase in the nuclear expression of GR beginning on Day 3, and it peaked on Day 14. The spleens of stressed mice displayed a reduction in size, disordered internal tissue structure and reduced cell proliferation. NK cells and M2-type macrophages exhibited immune cell subset alterations under stress, whereas T or B cells remained unaltered. Restraint stress can lead to pathomorphological alterations in spleen morphology, cell proliferation and immune cell counts in mice. These findings suggest that stress-induced pathological changes can disrupt immune regulation during stress.


Assuntos
Camundongos Endogâmicos C57BL , Receptores de Glucocorticoides , Restrição Física , Baço , Estresse Psicológico , Animais , Baço/patologia , Baço/metabolismo , Receptores de Glucocorticoides/metabolismo , Camundongos , Masculino , Estresse Psicológico/imunologia , Proliferação de Células , Fatores de Tempo , Células Matadoras Naturais/imunologia , Estresse Fisiológico , Macrófagos/imunologia , Macrófagos/metabolismo
18.
Forensic Sci Int ; 361: 112121, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38971138

RESUMO

Sudden unexplained death (SUD) is not uncommon in forensic pathology. Yet, diagnosis of SUD remains challenging due to lack of specific biomarkers. This study aimed to screen differentially expressed proteins (DEPs) and validate their usefulness as diagnostic biomarkers for SUD cases. We designed a three-phase investigation, where in the discovery phase, formalin-fixed paraffin-embedded (FFPE) heart specimens were screened through label-free proteomic analysis of cases dying from SUD, mechanical injury and carbon monoxide (CO) intoxication. A total of 26 proteins were identified to be DEPs for the SUD cases after rigorous criterion. Bioinformatics and Adaboost-recursive feature elimination (RFE) analysis further revealed that three of the 26 proteins (MYH6, COX5B and TNNT2) were potential discriminative biomarkers. In the training phase, MYH6 and COX5B were verified to be true DEPs in cardiac tissues from 29 independent SUD cases as compared with a serial of control cases (n = 42). Receiver operating characteristic (ROC) analysis illustrated that combination of MYH6 and COX5B achieved optimal diagnostic sensitivity (89.7 %) and specificity (84.4 %), with area under the curve (AUC) being 0.91. A diagnostic software based on the logistic regression formula derived from the training phase was then constructed. In the validation phase, the diagnostic software was applied to eight authentic SUD cases, seven (87.5 %) of which were accurately recognized. Our study provides a valid strategy towards practical diagnosis of SUD by integrating cardiac MYH6 and COX5B as dual diagnostic biomarkers.


Assuntos
Biomarcadores , Miocárdio , Cadeias Pesadas de Miosina , Proteômica , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Biomarcadores/metabolismo , Miosinas Cardíacas/genética , Miosinas Cardíacas/metabolismo , Estudos de Casos e Controles , Morte Súbita/etiologia , Patologia Legal/métodos , Miocárdio/metabolismo , Miocárdio/química , Cadeias Pesadas de Miosina/metabolismo , Cadeias Pesadas de Miosina/genética , Curva ROC , Sensibilidade e Especificidade
19.
Microorganisms ; 11(9)2023 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-37764177

RESUMO

Vibrio splendidus is a pathogen that infects a wide range of hosts, especially the sea cucumber species Apostichopus japonicus. Previous studies showed that the level of L-glutamic acid (L-Glu) significantly increased under heat stress, and it was found to be one of the best carbon sources used by V. splendidus AJ01. In this study, the effects of exogenous L-Glu on the coelomocyte viability, tissue status, and individual mortality of sea cucumbers were analyzed. The results showed that 10 mM of L-Glu decreased coelomocyte viability and increased individual mortality, with tissue rupture and pyknosis, while 0.1 mM of L-Glu slightly affected the survival of sea cucumbers without obvious damage at the cellular and tissue levels. Transcriptomic analysis showed that exogenous L-Glu upregulated 343 and downregulated 206 genes. Gene Ontology (GO) analysis showed that differentially expressed genes (DEGs) were mainly enriched in signaling and membrane formation, while a Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that DEGs were significantly enriched in the upregulated endocytosis and downregulated lysosomal pathways. The coelomocyte viability further decreased by 20% in the simultaneous presence of exogenous L-Glu and V. splendidus AJ01 compared with that in the presence of V. splendidus AJ01 infection alone. Consequently, a higher sea cucumber mortality was also observed in the presence of exogenous L-Glu challenged by V. splendidus AJ01. Real-time reverse transcriptase PCR showed that L-Glu specifically upregulated the expression of the fliC gene coding the subunit protein of the flagellar filament, promoting the swimming motility activity of V. splendidus. Our results indicate that L-Glu should be kept in a state of equilibrium, and excess L-Glu at the host-pathogen interface prompts the virulence of V. splendidus via the increase of bacterial motility.

20.
Anal Cell Pathol (Amst) ; 2023: 9979291, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37035018

RESUMO

Stress has become a universal biological phenomenon in the body, which leads to pathophysiological changes. However, the molecular network interactions between endoplasmic reticulum (ER) stress and ferroptosis under stressful conditions are not clear. For this purpose, we screened the gene expression profile of GSE173795 for intersection with ferroptosis genes and screened 68 differentially expressed genes (DEGs) (63 up-regulated, 5 down-regulated), mainly related to lipid and atherosclerosis, autophagy-animal, mitophagy-animal, focal adhesion, DNA replication, proteasome, oocyte meiosis, toll-like receptor signaling pathway, cell cycle, etc. Immune infiltration analysis revealed that stress resulted in decreased B cells memory, T cells CD8 and T cells CD4 memory resting, monocytes, macrophages M2, and increased B cells naive, T cells follicular helper, and macrophages M1. 19 core-DEGs (ASNS, TRIB3, ATF4, EIF2S1, CEBPG, RELA, HSPA5, DDIT3, STAT3, MAP3K5, HIF1A, HNF4A, MAPK14, HMOX1, CDKN1A, KRAS, SP1, SIRT1, EGFR) were screened, all of which were up-regulated DEGs. These biological processes and pathways were mainly involved in responding to ER stress, lipid and atherosclerosis, cellular response to stress, cellular response to chemical stress, and regulation of DNA-templated transcription in response to stress, etc. Spearman analysis did not find MAPK14 to be significantly associated with immune cells. Other core-DEGs were associated with immune cells, including B cells naive, T cells follicular helper, and monocytes. Based on core-DEGs, 283 miRNAs were predicted. Among the 22 miRNAs with highly cross-linked DEGs, 11 had upstream lncRNA, mainly targeting STAT3, SP1, CDKN1A, and SIRT1, and a total of 39 lncRNA were obtained. 85 potential drugs targeting 11 core-DEGs were identified and were expected to be potential immunotherapeutic agents for stress injury. Our experiments also confirmed that Liproxstatin-1 alleviates common cross-linked proteins between ER stress and ferroptosis. In conclusion, our study explored the molecular mechanisms and network interactions among stress-ER stress-ferroptosis from a novel perspective, which provides new research ideas for studying stressful injury.


Assuntos
Aterosclerose , Ferroptose , MicroRNAs , Proteína Quinase 14 Ativada por Mitógeno , RNA Longo não Codificante , Animais , Ferroptose/genética , Sirtuína 1 , Estresse do Retículo Endoplasmático/genética , Biologia Computacional/métodos , Lipídeos
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