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1.
Nature ; 630(8016): 437-446, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38599239

RESUMO

Gasdermin D (GSDMD) is the common effector for cytokine secretion and pyroptosis downstream of inflammasome activation and was previously shown to form large transmembrane pores after cleavage by inflammatory caspases to generate the GSDMD N-terminal domain (GSDMD-NT)1-10. Here we report that GSDMD Cys191 is S-palmitoylated and that palmitoylation is required for pore formation. S-palmitoylation, which does not affect GSDMD cleavage, is augmented by mitochondria-generated reactive oxygen species (ROS). Cleavage-deficient GSDMD (D275A) is also palmitoylated after inflammasome stimulation or treatment with ROS activators and causes pyroptosis, although less efficiently than palmitoylated GSDMD-NT. Palmitoylated, but not unpalmitoylated, full-length GSDMD induces liposome leakage and forms a pore similar in structure to GSDMD-NT pores shown by cryogenic electron microscopy. ZDHHC5 and ZDHHC9 are the major palmitoyltransferases that mediate GSDMD palmitoylation, and their expression is upregulated by inflammasome activation and ROS. The other human gasdermins are also palmitoylated at their N termini. These data challenge the concept that cleavage is the only trigger for GSDMD activation. They suggest that reversible palmitoylation is a checkpoint for pore formation by both GSDMD-NT and intact GSDMD that functions as a general switch for the activation of this pore-forming family.


Assuntos
Gasderminas , Lipoilação , Proteínas de Ligação a Fosfato , Espécies Reativas de Oxigênio , Animais , Feminino , Humanos , Masculino , Camundongos , Aciltransferases/metabolismo , Microscopia Crioeletrônica , Cisteína/metabolismo , Gasderminas/química , Gasderminas/metabolismo , Inflamassomos/metabolismo , Lipossomos/metabolismo , Lipossomos/química , Mitocôndrias/metabolismo , Proteínas de Ligação a Fosfato/química , Proteínas de Ligação a Fosfato/metabolismo , Piroptose , Espécies Reativas de Oxigênio/metabolismo , Células THP-1
2.
J Cell Mol Med ; 28(8): e18290, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38588015

RESUMO

Growth hormone inducible transmembrane protein (GHITM), one member of Bax inhibitory protein-like family, has been rarely studied, and the clinical importance and biological functions of GHITM in kidney renal clear cell carcinoma (KIRC) still remain unknown. In the present study, we found that GHITM was downregulated in KIRC. Aberrant GHITM downregulation related to clinicopathological feature and unfavourable prognosis of KIRC patients. GHITM overexpression inhibited KIRC cell proliferation, migration and invasion in vitro and in vivo. Mechanistically, GHITM overexpression could induce the downregulation of Notch1, which acts as an oncogene in KIRC. Overexpression of Notch1 effectively rescued the inhibitory effect induced by GHITM upregulation. More importantly, GHITM could regulate PD-L1 protein abundance and ectopic overexpression of GHITM enhanced the antitumour efficiency of PD-1 blockade in KIRC, which provided new insights into antitumour therapy. Furthermore, we also showed that YY1 could decrease GHITM level via binding to its promoter. Taken together, our study revealed that GHITM was a promising therapeutic target for KIRC, which could modulate malignant phenotype and sensitivity to PD-1 blockade of renal cancer cells via Notch signalling pathway.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/genética , Rim , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/genética , Fenótipo , Receptor de Morte Celular Programada 1
3.
Sci Immunol ; 9(94): eadn1452, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38530158

RESUMO

Plasma membrane perforation elicited by caspase cleavage of the gasdermin D (GSDMD) N-terminal domain (GSDMD-NT) triggers pyroptosis. The mechanisms underlying GSDMD membrane translocation and pore formation are not fully understood. Here, using a proteomic approach, we identified fatty acid synthase (FASN) as a GSDMD-binding partner. S-palmitoylation of GSDMD at Cys191/Cys192 (human/mouse), catalyzed by palmitoyl acyltransferases ZDHHC5 and ZDHHC9 and facilitated by reactive oxygen species (ROS), directly mediated membrane translocation of GSDMD-NT but not full-length GSDMD (GSDMD-FL). Palmitoylation of GSDMD-FL could be induced before inflammasome activation by stimuli such as lipopolysaccharide (LPS), consequently serving as an essential molecular event in macrophage priming. Inhibition of GSDMD palmitoylation suppressed macrophage pyroptosis and IL-1ß release, mitigated organ damage, and enhanced the survival of septic mice. Thus, GSDMD-NT palmitoylation is a key regulatory mechanism controlling GSDMD membrane localization and activation, which may offer an additional target for modulating immune activity in infectious and inflammatory diseases.


Assuntos
Piroptose , Animais , Humanos , Camundongos , Gasderminas , Lipoilação , Proteômica
4.
Neuroscience ; 540: 1-11, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38242279

RESUMO

Mitochondrial dysfunction, which results in the overproduction of oxygen free radicals, is a crucial mechanism underlying cerebral ischemia-reperfusion injury. 4'-Hydroxyl-2-substituted phenylnitronyl nitroxide (HPN), which is an antioxidant and free radical scavenger, can effectively scavenge oxygen free radicals, suggesting its potential as a protective agent against cerebral ischemia-reperfusion injury. In this study, we investigated the effects of HPN on mitochondrial function and apoptosis following cerebral ischemia/reperfusion injury in rats. Healthy adult SD rats were chosen as the experimental subjects, and the rat ischemia/reperfusion injury model was generated using the modified Zea Longa method. The administration of HPN significantly enhanced the activity of endogenous antioxidant enzymes, such as superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT). Additionally, HPN effectively preserved the morphology and function of mitochondria, reduced the protein and gene expression of Caspase-3 and Bax, increased the protein and gene expression of Bcl-2, mitigated neuronal apoptosis, improved neurological deficits, and decreased the volume of cerebral infarction. Of interest, the protective effect on brain tissue was more evident with increasing doses of HPN. These findings indicate that HPN can serve as an effective protective agent against cerebral ischemia-reperfusion injury.


Assuntos
Isquemia Encefálica , Doenças Mitocondriais , Óxidos de Nitrogênio , Traumatismo por Reperfusão , Humanos , Ratos , Animais , Sequestradores de Radicais Livres/farmacologia , Ratos Sprague-Dawley , Estresse Oxidativo , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Infarto Cerebral , Antioxidantes/farmacologia , Apoptose , Superóxido Dismutase/metabolismo , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/metabolismo , Substâncias Protetoras/farmacologia , Reperfusão , Radicais Livres
5.
Nat Commun ; 15(1): 386, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38195694

RESUMO

Both lytic and apoptotic cell death remove senescent and damaged cells in living organisms. However, they elicit contrasting pro- and anti-inflammatory responses, respectively. The precise cellular mechanism that governs the choice between these two modes of death remains incompletely understood. Here we identify Gasdermin E (GSDME) as a master switch for neutrophil lytic pyroptotic death. The tightly regulated GSDME cleavage and activation in aging neutrophils are mediated by proteinase-3 and caspase-3, leading to pyroptosis. GSDME deficiency does not alter neutrophil overall survival rate; instead, it specifically precludes pyroptosis and skews neutrophil death towards apoptosis, thereby attenuating inflammatory responses due to augmented efferocytosis of apoptotic neutrophils by macrophages. In a clinically relevant acid-aspiration-induced lung injury model, neutrophil-specific deletion of GSDME reduces pulmonary inflammation, facilitates inflammation resolution, and alleviates lung injury. Thus, by controlling the mode of neutrophil death, GSDME dictates host inflammatory outcomes, providing a potential therapeutic target for infectious and inflammatory diseases.


Assuntos
Gasderminas , Lesão Pulmonar , Humanos , Neutrófilos , Apoptose , Piroptose
6.
J Biomed Opt ; 29(Suppl 1): S11517, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38223679

RESUMO

Significance: Photoacoustic Doppler flowmetry offers quantitative blood perfusion information in addition to photoacoustic vascular contrast for rectal cancer assessment. Aim: We aim to develop and validate a correlational Doppler flowmetry utilizing an acoustic resolution photoacoustic microscopy (AR-PAM) system for blood perfusion analysis. Approach: To extract blood perfusion information, we implemented AR-PAM Doppler flowmetry consisting of signal filtering and conditioning, A-line correlation, and angle compensation. We developed flow phantoms and contrast agent to systemically investigate the flowmetry's efficacy in a series of phantom studies. The developed correlational Doppler flowmetry was applied to images collected during in vivo AR-PAM for post-treatment rectal cancer evaluation. Results: The linearity and accuracy of the Doppler flow measurement system were validated in phantom studies. Imaging rectal cancer patients treated with chemoradiation demonstrated the feasibility of using correlational Doppler flowmetry to assess treatment response and distinguish residual cancer from cancer-free tumor bed tissue and normal rectal tissue. Conclusions: A new correlational Doppler flowmetry was developed and validated through systematic phantom evaluations. The results of its application to in vivo patients suggest it could be a useful addition to photoacoustic endoscopy for post-treatment rectal cancer assessment.


Assuntos
Técnicas Fotoacústicas , Neoplasias Retais , Humanos , Fluxometria por Laser-Doppler/métodos , Reologia/métodos , Microscopia Acústica/métodos , Acústica , Neoplasias Retais/diagnóstico por imagem , Técnicas Fotoacústicas/métodos
7.
J Intensive Care Med ; 39(3): 257-267, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37723966

RESUMO

Objectives: To investigate the effect of our improved nursing strategy on prognosis in immunosuppressed patients with pneumonia and sepsis. Methods: Immunosuppressed patients (absolute lymphocyte count <1000 cells/mm3) with pneumonia and sepsis were enrolled and divided into a control group and treatment group. The treatment group received the improved nursing strategy. The primary outcome in this study was 28-day mortality. Results: In accordance with the study criteria, 1019 patients were finally enrolled. Compared with patients in the control group, those in the treatment group had significantly fewer days on mechanical ventilation [5 (4, 7) versus 5 (4, 7) days, P = .03] and lower intensive care unit (ICU) mortality [21.1% (132 of 627) vs 28.8% (113 of 392); P = .005] and 28-day mortality [22.2% (139 of 627) vs 29.8% (117 of 392); P = .006]. The treatment group also had a shorter duration of ICU stay [9 (5, 15) vs 11 (6, 22) days, P = .0001] than the control group. The improved nursing strategy acted as an independent protective factor in 28-day mortality: odds ratio 0.645, 95% confidence interval: 0.449-0.927, P = .018. Conclusion: Our improved nursing strategy shortened the duration of mechanical ventilation and the ICU stay and decreased ICU mortality and 28-day mortality in immunosuppressed patients with pneumonia and sepsis. Trial registration: ChiCTR.org.cn, ChiCTR-ROC-17010750. Registered 28 February 2017.


Assuntos
Pneumonia , Sepse , Humanos , Estudos Prospectivos , Respiração Artificial , Prognóstico , Sepse/terapia , Unidades de Terapia Intensiva , Estudos Retrospectivos
8.
Neurochem Res ; 49(3): 785-799, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38103103

RESUMO

Abundant investigations have shown that hypobaric hypoxia (HH) causes cognitive impairment, mostly attributed to oxidative stress, inflammation, and apoptosis. HPN (4'-hydroxyl-2-subsitiuted phenylnitronyl nitroxide) is an excellent free radical scavenger with anti-inflammatory and anti-apoptotic activities. Our previous study has found that HPN exhibited neuroprotective effect on HH induced brain injury. In the present study, we examined the protective effect and potential mechanism of HPN on HH-induced cognitive impairment. Male mice were exposed to HH at 8000 m for 3 days with and without HPN treatment. Cognitive performance was assessed by the eight-arm radical maze. The histological changes were assayed by Nissle staining. The hippocampus cell apoptosis was detected by Tunnel staining. The levels of inflammatory cytokines and oxidative stress markers were detected. The expression of oxidative stress, inflammation-related and apoptosis-related proteins was determined by western blot. HPN administration significantly and mitigated HH induced histological damages and spatial memory loss with the evidence of decreased working memory error (WME), reference memory error (RME), total errors (TE) and total time (TT). In addition, HPN treatment significantly decreased the content of H2O2 and MDA, increased the levels of SOD, CAT, GSH-Px and GSH, and inhibited the synthesis of TNF-α, IL-1ß and IL-6. Moreover, HPN administration could down-regulate the expression of NF-κB, TNF-α, Bax, and cleaved caspase-3 and up-regulate the expression of Nrf2, HO-1 and Bcl-2. The number of apoptotic cells was also significantly decreased in the hippocampus of mice in the HPN group. There results indicate that HPN improve HH-induced cognitive impairment by alleviating oxidative stress damage, suppressing inflammatory response and apoptosis and may be a powerful candidate compound for alleviating memory loss induced by HH.


Assuntos
Disfunção Cognitiva , Óxidos de Nitrogênio , Fator de Necrose Tumoral alfa , Camundongos , Masculino , Animais , Fator de Necrose Tumoral alfa/metabolismo , Peróxido de Hidrogênio/farmacologia , Estresse Oxidativo , Hipóxia/metabolismo , Apoptose , Transtornos da Memória/tratamento farmacológico , Transtornos da Memória/etiologia , Proteínas Reguladoras de Apoptose/metabolismo , Inflamação/metabolismo , Disfunção Cognitiva/tratamento farmacológico
9.
J Med Educ Curric Dev ; 10: 23821205231219396, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38152834

RESUMO

Objectives: The routine teaching mode of diabetes mellitus (DM) is divided into various sub-majors of medical laboratory, which is not conducive to clinical laboratory physicians quickly mastering relevant knowledge. A novel DM laboratory testing pathway is established to improve teaching efficiency and enhance the effects of talent cultivation in laboratory medicine. Methods: The guidelines and expert consensuses of DM were gathered from professional websites and databases. The clinical laboratory diagnostic pathway was formulated, and the questionnaire and mutual evaluation were used to evaluate the teaching effectiveness of 8-year undergraduate students enrolled in 2018 and enrolled in 2019, respectively. Results: Clinical laboratory physicians developed and approved the DM clinical laboratory diagnostic pathway, which included the entire process of DM diagnosis and differential diagnosis, drug selection, treatment impact monitoring, prognosis evaluation, etc. The results of the questionnaires showed that, in comparison to the teaching mode used with the students enrolled in 2018 and enrolled in 2019, the percentages of more improvement and significant improvement were significantly increased (P < 0.01) and the percentages of no improvement and slight improvement were significantly decreased (P < 0.01). Following the instruction of the DM clinical laboratory diagnostic route, the results were greatly improved, including points emphasized and the accuracy of responding to questions, among other things, according to the teachers' and students' mutual evaluation (P < 0.05). Conclusions: To enhance the teaching quality in laboratory medicine, it is required to build the disease clinical laboratory diagnostic pathway for a novel teaching method. This may boost teachers' and students' confidence and broaden their knowledge.

10.
Front Med ; 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37991709

RESUMO

This cohort study was performed to explore the influence of intensive care unit (ICU) quality on in-hospital mortality of veno-venous (V-V) extracorporeal membrane oxygenation (ECMO)-supported patients in China. The study involved all V-V ECMO-supported patients in 318 of 1700 tertiary hospitals from 2017 to 2019, using data from the National Clinical Improvement System and China National Critical Care Quality Control Center. ICU quality was assessed by quality control indicators and capacity parameters. Among the 2563 V-V ECMO-supported patients in 318 hospitals, a significant correlation was found between ECMO-related complications and prognosis. The reintubation rate within 48 hours after extubation and the total ICU mortality rate were independent risk factors for higher in-hospital mortality of V-V ECMO-supported patients (cutoff: 1.5% and 7.0%; 95% confidence interval: 1.05-1.48 and 1.04-1.45; odds ratios: 1.25 and 1.23; P = 0.012 and P = 0.015, respectively). Meanwhile, the V-V ECMO center volume was a protective factor (cutoff of ≥ 50 cases within the 3-year study period; 95% confidence interval: 0.57-0.83, odds ratio: 0.69, P = 0.0001). The subgroup analysis of 864 patients in 11 high-volume centers further strengthened these findings. Thus, ICU quality may play an important role in improving the prognosis of V-V ECMO-supported patients.

12.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 35(10): 1085-1092, 2023 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-37873715

RESUMO

OBJECTIVE: To investigate the effect of improved nursing strategy on prognosis of older immunosuppressed patients with pneumonia and sepsis. METHODS: A prospective study was conducted. The older immunosuppressed patients with pneumonia and sepsis admitted to the department of intensive care medicine and emergency intensive care unit (ICU) of Peking Union Medical College Hospital from January 2017 to July 2022 were enrolled. In the first stage (from January 2017 to December 2019), patients received the original nursing strategy (original nursing strategy group), including: (1) nurses were randomly assigned; (2) routine terminal cleaning; (3) ICU environmental cleaning twice a day; (4) oral care was performed with chlorhexidine twice a day; (5) original lung physiotherapy [head of bed elevated at 30 degree angle-45 degree angle, maintaining a Richmond agitation-sedation scale (RASS) -2 to 1, sputum aspiration as needed]. After 1 month of learning and training of the modified nursing treatment strategy for nurses and related medical staff, the patients in the second stage (from February 2020 to July 2022) received the improved nursing strategy (improved nursing strategy group). The improved nursing strategy improved the hospital infection prevention and control strategy and lung physical therapy strategy on the basis of the original nursing strategy, including: (1) nurses were fixed assigned; (2) patients were placed in a private room; (3) enhanced terminal cleaning; (4) ICU environmental cleaning four times a day; (5) education and training in hand hygiene among health care workers was improved; (6) bathing with 2% chlorhexidinegluconate was performed once daily; (7) oral care with a combination of chlorhexidine and colistin was provided every 6 hours; (8) surveillance of colonization was conducted; (9) improved lung physiotherapy (on the basis of the original lung physiotherapy, delirium score was assessed to guide early mobilization of the patients; airway drainage was enhanced, the degree of airway humidification was adjusted according to the sputum properties, achieving sputum viscosity grade II; lung ultrasound was also used for lung assessment, and patients with atelectasis were placed in high lateral position and received the lung recruitment maneuver). Baseline patient information were collected, including gender, age, underlying diseases, source of admission, disease severity scores, vital signs, ventilatory parameters, blood gas analysis, life-sustaining treatments, clinical laboratory evaluation, indicators of infection and inflammation, pathogens and drug therapy. The primary outcome was 28-day mortality, and the secondary outcomes were duration of mechanical ventilation, length of ICU stay, and ICU mortality. Multivariate Logistic regression analysis was used to determine the risk factors for 28-day death in older immunosuppressed patients with pneumonia and sepsis. RESULTS: Finally, 550 patients were enrolled, including 199 patients in the original nursing strategy group and 351 patients in the improved nursing strategy group. No significant differences were found in gender, age, underlying diseases, source of admission, disease severity scores, vital signs, ventilatory parameters, blood gas analysis, life-sustaining treatments, clinical laboratory evaluation, indicators of infection and inflammation, coexisting pathogens or drug therapy between the two groups. Compared with patients in the original nursing strategy group, those in the improved nursing strategy group had significantly fewer duration of mechanical ventilation and length of ICU stay [duration of mechanical ventilation (days): 5 (4, 7) vs. 5 (4, 9), length of ICU stay (days): 11 (6, 17) vs. 12 (6, 23), both P < 0.01], and lower ICU mortality and 28-day mortality [ICU mortality: 23.9% (84/351) vs. 32.7% (65/199), 28-day mortality: 23.1% (81/351) vs. 33.7% (67/199), both P < 0.05]. Multivariate Logistic regression analysis showed that the improved nursing strategy acted as an independent protective factor in 28-day death of older immunosuppressed patients with pneumonia and sepsis [odds ratio (OR) = 0.543, 95% confidence interval (95%CI) was 0.334-0.885, P = 0.014]. CONCLUSIONS: Improved nursing strategy shortened the duration of mechanical ventilation and the length of ICU stay, and decreased ICU mortality and 28-day mortality in older immunosuppressed patients with pneumonia and sepsis, significantly improving the short-term prognosis of such patients.


Assuntos
Pneumonia , Sepse , Humanos , Idoso , Estudos Prospectivos , Clorexidina/uso terapêutico , Unidades de Terapia Intensiva , Prognóstico , Sepse/terapia , Inflamação
13.
Redox Rep ; 28(1): 2259246, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37728223

RESUMO

Mitochondrial dysfunction leading to overproduction of oxygen free radicals is an important event in the development of Alzheimer's disease. Tetrahydroxy stilbene glycoside (TSG) is one of the main effective components of Polygonum multiflorum and has a certain free radical scavenging effect. We synthesized tetrahydroxy stilbene glycoside derivatives (Mito-TSGs) that can cross the mitochondrial membrane and may provide effective protection against Alzheimer's disease. This experiment investigates the protective mechanism of tetrahydroxy stilbene glycoside derivatives against mitochondrial free radical damage and apoptosis in APP695V717I transgenic model mice. The experimental subjects were healthy 3-month-old APP695V717I transgenic model mice, while C57BL/6J mice of the same age and genetic background served as controls. The results demonstrated that the tetrahydroxy stilbene glycoside derivatives significantly improved mouse behavioral performance. It also led to a decrease in the levels of H2O2, NO, MDA, and LD, along with an increase in LDH activity and in the antioxidant enzyme activity of SOD, CAT, and GSH-Px. Moreover, it elevated the mitochondrial membrane potential, decreased the gene and protein expression of Caspase-3 and Bax, and increased the gene and protein expression of Bcl-2. Notably, the effectiveness of tetrahydroxy stilbene glycoside derivatives was superior to that of traditional tetrahydroxy stilbene glycoside.


Assuntos
Doença de Alzheimer , Estilbenos , Camundongos , Animais , Camundongos Endogâmicos C57BL , Glicosídeos/farmacologia , Camundongos Transgênicos , Peróxido de Hidrogênio , Apoptose , Antioxidantes , Radicais Livres , Estilbenos/farmacologia
14.
EMBO Rep ; 24(10): e56009, 2023 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-37642636

RESUMO

Hematopoietic stem and progenitor cells (HSPCs) are cells mainly present in the bone marrow and capable of forming mature blood cells. However, the epigenetic mechanisms governing the homeostasis of HSPCs remain elusive. Here, we demonstrate an important role for histone deacetylase 6 (HDAC6) in regulating this process. Our data show that the percentage of HSPCs in Hdac6 knockout mice is lower than in wild-type mice due to decreased HSPC proliferation. HDAC6 interacts with isocitrate dehydrogenase 1 (IDH1) and deacetylates IDH1 at lysine 233. The deacetylation of IDH1 inhibits its catalytic activity and thereby decreases the 5-hydroxymethylcytosine level of ten-eleven translocation 2 (TET2) target genes, changing gene expression patterns to promote the proliferation of HSPCs. These findings uncover a role for HDAC6 and IDH1 in regulating the homeostasis of HSPCs and may have implications for the treatment of hematological diseases.


Assuntos
Medula Óssea , Células-Tronco Hematopoéticas , Animais , Camundongos , Desacetilase 6 de Histona/genética , Desacetilase 6 de Histona/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Células da Medula Óssea/metabolismo , Homeostase
15.
Proc Natl Acad Sci U S A ; 120(35): e2303814120, 2023 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-37603754

RESUMO

Neutrophil recruitment to sites of infection and inflammation is an essential process in the early innate immune response. Upon activation, a subset of neutrophils rapidly assembles the multiprotein complex known as the NLRP3 inflammasome. The NLRP3 inflammasome forms at the microtubule organizing center, which promotes the formation of interleukin (IL)-1ß and IL-18, essential cytokines in the immune response. We recently showed that mice deficient in NLRP3 (NLRP3-/-) have reduced neutrophil recruitment to the peritoneum in a model of thioglycolate-induced peritonitis. Here, we tested the hypothesis that this diminished recruitment could be, in part, the result of defects in neutrophil chemotaxis. We find that NLRP3-/- neutrophils show loss of cell polarization, as well as reduced directionality and velocity of migration toward increasing concentrations of leukotriene B4 (LTB4) in a chemotaxis assay in vitro, which was confirmed through intravital microscopy of neutrophil migration toward a laser-induced burn injury of the liver. Furthermore, pharmacologically blocking NLRP3 inflammasome assembly with MCC950 in vitro reduced directionality but preserved nondirectional movement, indicating that inflammasome assembly is specifically required for polarization and directional chemotaxis, but not cell motility per se. In support of this, pharmacological breakdown of the microtubule cytoskeleton via nocodazole treatment induced cell polarization and restored nondirectional cell migration in NLRP3-deficient neutrophils in the LTB4 gradient. Therefore, NLRP3 inflammasome assembly is required for establishment of cell polarity to guide the directional chemotactic migration of neutrophils.


Assuntos
Quimiotaxia , Leucotrieno B4 , Proteína 3 que Contém Domínio de Pirina da Família NLR , Animais , Camundongos , Inflamassomos , Leucotrieno B4/metabolismo , Neutrófilos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo
16.
Biomed Opt Express ; 14(7): 3225-3233, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37497483

RESUMO

We demonstrate the use of our miniature optical coherence tomography catheter to acquire three-dimensional human fallopian tube images. Images of the fallopian tube's tissue morphology, vasculature, and tissue heterogeneity distribution are enhanced by adaptive thresholding, masking, and intensity inverting, making it easier to differentiate malignant tissue from normal tissue. The results show that normal fallopian tubes tend to have rich vasculature accompanied by a patterned tissue scattering background, features that do not appear in malignant cases. This finding suggests that miniature OCT catheters may have great potential for fast optical biopsy of the fallopian tube.

17.
Bioorg Chem ; 139: 106652, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37390632

RESUMO

Primary liver cancer is one of the most common malignant cancers of the digestive system that lacks effective chemotherapeutic drugs in clinical settings. Camptothecin (CPT) and its derivatives have been approved for cancer treatment; however, their application is limited by their systemic toxicity. For lead optimization in new drug discovery stages, fluorination is an effective and robust approach to increase the bioavailability and optimize the pharmacokinetics of candidate compounds, thereby improving their efficacy. To obtain new and highly active CPT derivatives, we designed, synthesized, and evaluated two new fluorinated CPT derivatives, 9-fluorocamptothecin (A1) and 7-ethyl-9-fluorocamptothecin (A2), in this study. In vitro, A1 and A2 exhibited more robust anti-tumor activity than topotecan (TPT) in various cancer cells, particularly hepatocellular carcinoma (HCC) cells. In vivo, A1 and A2 exhibited greater anti-tumor activity than TPT in both AKT/Met induced primary HCC mouse models and implanted HepG2 cell xenografts. Acute toxicity tests revealed that A1 and A2 were not lethal and did not cause significant body weight loss at high doses. Moreover, A1 and A2 exhibited no significant toxicity in the mouse liver, heart, lung, spleen, kidney, and hematopoietic systems at therapeutic doses. Mechanistically, A1 and A2 blocked HCC cell proliferation by inhibiting the enzymatic activity of Topo I, subsequently inducing DNA damage, cell cycle arrest, and apoptosis. In summary, our results indicate that fluorination improves the anti-tumor activity of CPT while decreasing its toxicity and highlight the application potential of fluorination products A1 and A2 in clinical settings.


Assuntos
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Animais , Camundongos , Camptotecina/farmacologia , Camptotecina/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , DNA Topoisomerases Tipo I/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Topotecan/farmacologia , Inibidores da Topoisomerase I/farmacologia , Inibidores da Topoisomerase I/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico
18.
BMC Med Educ ; 23(1): 485, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37391727

RESUMO

BACKGROUND: The teaching of critical care medicine is a very important task, especially during the COVID-19 pandemic. The understanding of critical care parameters is the foundation and core, which is conducive to the formation of clinical thinking. This study is to evaluate the training effect of teaching of critical care parameters based on an online platform, and explore the teaching methods of critical care medicine that can help to cultivate trainees' clinical thinking and practical ability. METHODS: Questionnaires were released before and after the training through the official new media platform "Yisheng" application (APP) of China Medical Tribune involving 1109 participants. The trainees who filled in the questionnaire in APP and received training were randomly selected as the investigated population. Statistical description and analysis were carried out using SPSS 20.0 and Excel 2020. RESULTS: The trainees were mainly attending physicians in tertiary hospitals and above. Among all critical care parameters, trainees paid more attention to critical hemodynamics, respiratory mechanics, severity of illness scoring systems, critical ultrasound, and critical hemofiltration. The degree of satisfaction with the courses was high, especially the course of critical hemodynamics was scored the highest. The trainees believed that the course contents were of great help to clinical work. However, no significant difference was found in the trainees' understanding or cognition of the connotation of the parameters before and after the training. CONCLUSION: Teaching of critical care parameters based on an online platform is conducive to improving and consolidating the clinical care ability of trainees. However, it is still necessary to strengthen the cultivation of clinical thinking in critical care. In the future, the integration of theory with practice must be strengthened in clinical practice, ultimately achieving the homogeneous diagnosis and treatment of patients with critical illness.


Assuntos
COVID-19 , Pandemias , Humanos , COVID-19/epidemiologia , Pensamento , Cognição , Cuidados Críticos
19.
Front Oncol ; 13: 1176637, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37274283

RESUMO

Background: As one of the most prevalent genitourinary cancers, bladder cancer (BLCA) is associated with high morbidity and mortality. Currently, limited indicators are available for early detection and diagnosis of bladder cancer, and there is a lack of specific biomarkers for evaluating the prognosis of BLCA patients. This study aims to identify critical genes that affect bladder cancer immunity to improve the diagnosis and prognosis of bladder cancer and to identify new biomarkers and targets for immunotherapy. Methods: Two GEO datasets were used to screen differentially expressed genes (DEGs). The STRING database was used to construct a protein-protein interaction network of DEGs, and plug-in APP CytoHubba in Cytoscape was used to identify critical genes in the network. GO and KEGG analyses explored the functions and pathways of differential gene enrichment. We used GEPIA to validate the expression of differential genes, their impact on patient survival, and their relationship to clinicopathological parameters. Additionally, hub genes were verified using qRT-PCR and Western blotting. Immune infiltration analysis and multiple immunohistochemistry reveal the impact of Hub genes on the tumor microenvironment. Result: We screened out 259 differential genes, and identified 10 key hub genes by the degree algorithm. Four genes (ACTA2, FLNA, TAGLN, and TPM1) were associated with overall or disease-free survival in BLCA patients and were significantly associated with clinical parameters. We experimentally confirmed that the mRNA and protein levels of these four genes were significantly decreased in bladder cancer cells. Immunoassays revealed that these four genes affect immune cell infiltration in the tumor microenvironment; they increased the polarization of M2 macrophages. Conclusion: These four genes affect the tumor microenvironment of bladder cancer, provide a new direction for tumor immunotherapy, and have significant potential in the diagnosis and prognosis of bladder cancer.

20.
Am J Cancer Res ; 13(4): 1295-1309, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37168327

RESUMO

microRNA-203 (miR203) plays an important role in the formation and development of multiple types of cancers. However, its role in hepatic carcinogenesis has not been well studied. Mitogen-activated protein kinase signaling is known to be activated in hepatocellular carcinoma (HCC), but there is a lack of effective drugs targeting this pathway for HCC treatment. In this study, we investigated the role of miR203 in HCC and the underlying mechanism. We found that miR203 was significantly downregulated in HCC cell lines and patient tissues compared with a hepatocyte cell line (L02) or normal liver tissues. Restoration of miR203 inhibited HCC cell growth and induced cell cycle arrest and apoptosis. In primary and xenograft HCC mouse models, miR203 also significantly blocked HCC growth. Bioinformatic analysis indicated that miR203 directly binds to the 3'UTR of NRas mRNA, resulting in decreased expression of NRas and inactivation of mitogen-activated protein kinase (MAPK) signaling. Activation of MAPK signaling by ectopic NRas expression rescued the cell proliferation blocked by miR203. Together, our findings illustrate the fundamental role of miR203 as a natural inhibitor of RAS/MAPK signaling in hepatic carcinogenesis in vitro and in vivo. In light of the critical and universal activation of the MAPK pathway in HCC, miR203 has the potential to serve as a nucleotide drug for the treatment of HCC with activated MAPK signaling.

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