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1.
Mol Biol Rep ; 51(1): 607, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38704801

RESUMO

BACKGROUND: Intracerebral hemorrhage (ICH) is a critical neurological condition with few treatment options, where secondary immune responses and specific cell death forms, like pyroptosis, worsen brain damage. Pyroptosis involves gasdermin-mediated membrane pores, increasing inflammation and neural harm, with the NLRP3/Caspase-1/GSDMD pathway being central to this process. Peroxiredoxin II (Prx II), recognized for its mitochondrial protection and reactive oxygen species (ROS) scavenging abilities, appears as a promising neuronal pyroptosis modulator. However, its exact role and action mechanisms need clearer definition. This research aims to explore Prx II impact on neuronal pyroptosis and elucidate its mechanisms, especially regarding endoplasmic reticulum (ER) stress and oxidative stress-induced neuronal damage modulation. METHODS AND RESULTS: Utilizing MTT assays, Microscopy, Hoechst/PI staining, Western blotting, and immunofluorescence, we found Prx II effectively reduces LPS/ATP-induced pyroptosis and neuroinflammation in HT22 hippocampal neuronal cells. Our results indicate Prx II's neuroprotective actions are mediated through PI3K/AKT activation and ER stress pathway inhibition, diminishing mitochondrial dysfunction and decreasing neuronal pyroptosis through the ROS/MAPK/NF-κB pathway. These findings highlight Prx II potential therapeutic value in improving intracerebral hemorrhage outcomes by lessening secondary brain injury via critical signaling pathway modulation involved in neuronal pyroptosis. CONCLUSIONS: Our study not only underlines Prx II importance in neuroprotection but also opens new therapeutic intervention avenues in intracerebral hemorrhage, stressing the complex interplay between redox regulation, ER stress, and mitochondrial dynamics in neuroinflammation and cell death management.


Assuntos
Estresse do Retículo Endoplasmático , Estresse Oxidativo , Peroxirredoxinas , Piroptose , Animais , Camundongos , Linhagem Celular , Hemorragia Cerebral/metabolismo , Hemorragia Cerebral/tratamento farmacológico , Hemorragia Cerebral/complicações , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Hipocampo/metabolismo , Hipocampo/patologia , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Peroxirredoxinas/metabolismo , Piroptose/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
2.
Acta Pharmacol Sin ; 45(8): 1752-1764, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38570601

RESUMO

Morphine and morphine-6-glucuronide (M6G) produce central nervous system (CNS) effects by activating mu-opioid receptors, while naloxone is used mainly for the reversal of opioid overdose, specifically for the fatal complication of respiratory depression, but also for alleviating opioid-induced side effects. In this study we developed a physiologically-based pharmacokinetic-pharmacodynamic (PBPK-PD) model to simultaneously predict pharmacokinetics and CNS effects (miosis, respiratory depression and analgesia) of morphine as well as antagonistic effects of naloxone against morphine. The pharmacokinetic and pharmacodynamic parameters were obtained from in vitro data, in silico, or animals. Pharmacokinetic and pharmacodynamic simulations were conducted using 39 and 36 clinical reports, respectively. The pharmacokinetics of morphine and M6G following oral or intravenous administration were simulated, and the PBPK-PD model was validated using clinical observations. The Emax model correlated CNS effects with free concentrations of morphine and M6G in brain parenchyma. The predicted CNS effects were compared with observations. Most clinical observations fell within the 5th-95th percentiles of simulations based on 1000 virtual individuals. Most of the simulated area under the concentration-time curve or peak concentrations also fell within 0.5-2-fold of observations. The contribution of morphine to CNS effects following intravenous or oral administration was larger than that of M6G. Pharmacokinetics and antagonistic effects of naloxone on CNS effects were also successfully predicted using the developed PBPK-PD model. In conclusion, the pharmacokinetics and pharmacodynamics of morphine and M6G, antagonistic effects of naloxone against morphine-induced CNS effects may be successfully predicted using the developed PBPK-PD model based on the parameters derived from in vitro, in silico, or animal studies.


Assuntos
Modelos Biológicos , Morfina , Naloxona , Antagonistas de Entorpecentes , Naloxona/farmacocinética , Naloxona/farmacologia , Humanos , Morfina/farmacocinética , Morfina/administração & dosagem , Morfina/farmacologia , Antagonistas de Entorpecentes/farmacocinética , Antagonistas de Entorpecentes/farmacologia , Antagonistas de Entorpecentes/administração & dosagem , Animais , Derivados da Morfina/farmacocinética , Sistema Nervoso Central/efeitos dos fármacos , Sistema Nervoso Central/metabolismo , Analgésicos Opioides/farmacocinética , Analgésicos Opioides/administração & dosagem , Masculino , Simulação por Computador , Administração Oral , Adulto , Administração Intravenosa , Feminino
3.
Acta Pharmacol Sin ; 45(7): 1406-1424, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38589687

RESUMO

Acute kidney injury (AKI) is often accompanied by uremic encephalopathy resulting from accumulation of uremic toxins in brain possibly due to impaired blood-brain barrier (BBB) function. Anionic uremic toxins are substrates or inhibitors of organic anionic transporters (OATs). In this study we investigated the CNS behaviors and expression/function of BBB OAT3 in AKI rats and mice, which received intraperitoneal injection of cisplatin 8 and 20 mg/kg, respectively. We showed that cisplatin treatment significantly inhibited the expressions of OAT3, synaptophysin and microtubule-associated protein 2 (MAP2), impaired locomotor and exploration activities, and increased accumulation of uremic toxins in the brain of AKI rats and mice. In vitro studies showed that uremic toxins neither alter OAT3 expression in human cerebral microvascular endothelial cells, nor synaptophysin and MAP2 expressions in human neuroblastoma (SH-SY5Y) cells. In contrast, tumour necrosis factor alpha (TNFα) and the conditioned medium (CM) from RAW264.7 cells treated with indoxyl sulfate (IS) significantly impaired OAT3 expression. TNFα and CM from IS-treated BV-2 cells also inhibited synaptophysin and MAP2 expressions in SH-SY5Y cells. The alterations caused by TNFα and CMs in vitro, and by AKI and TNFα in vivo were abolished by infliximab, a monoclonal antibody designed to intercept and neutralize TNFα, suggesting that AKI impaired the expressions of OAT3, synaptophysin and MAP2 in the brain via IS-induced TNFα release from macrophages or microglia (termed as IS-TNFα axis). Treatment of mice with TNFα (0.5 mg·kg-1·d-1, i.p. for 3 days) significantly increased p-p65 expression and reduced the expressions of Nrf2 and HO-1. Inhibiting NF-κB pathway, silencing p65, or activating Nrf2 and HO-1 obviously attenuated TNFα-induced downregulation of OAT3, synaptophysin and MAP2 expressions. Significantly increased p-p65 and decreased Nrf2 and HO-1 protein levels were also detected in brain of AKI mice and rats. We conclude that AKI inhibits the expressions of OAT3, synaptophysin and MAP2 due to IS-induced TNFα release from macrophages or microglia. TNFα impairs the expressions of OAT3, synaptophysin and MAP2 partly via activating NF-κB pathway and inhibiting Nrf2-HO-1 pathway.


Assuntos
Injúria Renal Aguda , Cisplatino , Indicã , Fator de Necrose Tumoral alfa , Animais , Injúria Renal Aguda/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Humanos , Camundongos , Masculino , Células RAW 264.7 , Ratos , Camundongos Endogâmicos C57BL , Transportadores de Ânions Orgânicos Sódio-Independentes/metabolismo , Ratos Sprague-Dawley , Sinaptofisina/metabolismo , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/efeitos dos fármacos , Uremia/metabolismo , Uremia/complicações , Linhagem Celular Tumoral
4.
Arch Toxicol ; 98(8): 2429-2439, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38722348

RESUMO

With advances in next-generation sequencing technology, there is growing evidence that the gut microbiome plays a key role in the host's innate and adaptive immune system. Gut microbes and their metabolites directly or indirectly regulate host immune cells. Crucially, dysregulation of the gut microbiota is often associated with many immune system diseases. In turn, microbes modulate disease immunotherapy. Data from preclinical to clinical studies suggest that the gut microbiota may influence the effectiveness of tumor immunotherapy, particularly immune checkpoint inhibitors (ICIs). In addition, the most critical issue now is a COVID-19 vaccine that generates strong and durable immunity. A growing number of clinical studies confirm the potential of gut microbes to enhance the efficacy of COVID-19 vaccines. However, it is still unclear how gut bacteria interact with immune cells and what treatments are based on gut microbes. Here, we outline recent advances in the effects and mechanisms of the gut microbiota and its metabolites (tryptophan metabolites, bile acids, short-chain fatty acids, and inosine) on different immune cells (dendritic cells, CD4+T cells, and macrophages). It also highlights innovative intervention strategies and clinical trials of microbiota-based checkpoint blocking therapies for tumor immunity, and ongoing efforts to maintain the long-term immunogenicity of COVID-19 vaccines. Finally, the challenges to be overcome in this area are discussed. These provide an important basis for further research and clinical translation of gut microbiota.


Assuntos
COVID-19 , Microbioma Gastrointestinal , Imunoterapia , Humanos , Microbioma Gastrointestinal/imunologia , Imunoterapia/métodos , COVID-19/imunologia , COVID-19/prevenção & controle , COVID-19/terapia , Vacinas contra COVID-19/imunologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Inibidores de Checkpoint Imunológico/farmacologia , Animais , SARS-CoV-2/imunologia , Neoplasias/imunologia , Neoplasias/terapia
5.
Angew Chem Int Ed Engl ; 63(11): e202319850, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38273811

RESUMO

In contrast with the well-established C(sp2 )-SCF3 cross-coupling to forge the Ar-SCF3 bond, the corresponding enantioselective coupling of readily available alkyl electrophiles to forge chiral C(sp3 )-SCF3 bond has remained largely unexplored. We herein disclose a copper-catalyzed enantioselective radical C(sp3 )-SCF3 coupling of a range of secondary/tertiary benzyl radicals with the easily available (Me4 N)SCF3 reagent. The key to the success lies in the utilization of chiral phosphino-oxazoline-derived anionic N,N,P-ligands through tuning electronic and steric effects for the simultaneous control of the reaction initiation and enantioselectivity. This strategy can successfully realize two types of asymmetric radical reactions, including enantioconvergent C(sp3 )-SCF3 cross-coupling of racemic benzyl halides and three-component 1,2-carbotrifluoromethylthiolation of arylated alkenes under mild reaction conditions. It therefore provides a highly flexible platform for the rapid assembly of an array of enantioenriched SCF3 -containing molecules of interest in organic synthesis and medicinal chemistry.

6.
Front Pharmacol ; 15: 1324848, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38549674

RESUMO

Background: Prophylactic antibacterial drugs are used for patients with liver cirrhosis and upper gastrointestinal bleeding, and independent studies have concluded that they can decrease the rate of infection, mortality, and rebleeding in these diseases. However, no comprehensive assessment of this effect has been reported in recent years and available data pertaining to the prognostic implications of diverse categories of antibiotic prophylaxis in individuals afflicted with cirrhosis are notably limited. The objective of this article is to assess the clinical effectiveness of prophylactic antibacterial drugs for patients with liver cirrhosis and upper gastrointestinal bleeding. Methods: Relevant randomized controlled studies and cohort studies which examined the value of prophylactic antibacterial drugs for patients with liver cirrhosis and upper gastrointestinal bleeding were retrieved via Cochrane Library, EMBASE, MedLine, and Web of Science. The search period was from database inception until 30 April 2023. Summing up the relevant data, the dichotomous variable was statistically analysed using the relative risk (RR) value and its 95% confidence interval (CI) and the continuous variable using the mean difference (MD) value and its 95% CI. All analyses were performed using Revman 5.4 software. The study has been registered on the PROSPERO website under registration number CRD42022343352. Results: Twenty-six studies (18 RCTs and 8 cohort studies, including 13,670 participants) were included to evaluate the effect of antibacterial prophylaxis versus no antibacterial prophylaxis or placebo. Prophylactic antibiotics reduced mortality rates (RR 0.66, 95% CI 0.51-0.83), infection rates (RR 0.41, 95% CI 0.35-0.49), rebleeding rates (RR 0.42, 95% CI 0.31-0.56), and length of hospital stay (MD -5.29, 95% CI -7.53, -3.04). Subgroup analysis revealed that the prophylactic administration of quinolone antimicrobials demonstrated the most favorable efficacy, followed by cephalosporins. Both interventions were effective in averting infections frequently observed in patients with liver cirrhosis and upper gastrointestinal bleeding. Conclusion: Based on our investigation, the prophylactic antibacterial drugs confers noteworthy advantages in patients afflicted by liver cirrhosis with upper gastrointestinal bleeding. It has been associated with reductions in mortality, infection incidence, rebleeding occurrences, and the duration of hospitalization. Among prophylactic antibacterial options, quinolones emerged as the foremost choice, with cephalosporins ranking closely thereafter. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022343352, identifier CRD42022343352.

7.
Nat Commun ; 15(1): 4702, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38830878

RESUMO

Magnetoelectric materials, which encompass coupled magnetic and electric polarizabilities within a single phase, hold great promises for magnetic controlled electronic components or electric-field controlled spintronics. However, the realization of ideal magnetoelectric materials remains tough due to the inborn competion between ferroelectricity and magnetism in both levels of symmetry and electronic structure. Herein, we introduce a methodology for constructing single phase paramagnetic ferroelectric molecule [TMCM][FeCl4], which shows low-magnetic-field magnetoelectricity at room temperature. By applying a low magnetic field (≤1 kOe), the halogen Cl‧‧‧Cl distance and the volume of [FeCl4]- anions could be manipulated. This structural change causes a characteristic magnetostriction hysteresis, resulting in a substantial deformation of ~10-4 along the a-axis under an in-plane magnetic field of 2 kOe. The magnetostrictive effect is further qualitatively simulated by density functional theory calculations. Furthermore, this mechanical deformation significantly dampens the ferroelectric polarization by directly influencing the overall dipole configuration. As a result, it induces a remarkable α31 component (~89 mV Oe-1 cm-1) of the magnetoelectric tensor. And the magnetoelectric coupling, characterized by the change of polarization, reaches ~12% under 40 kOe magnetic field. Our results exemplify a design methodology that enables the creation of room-temperature magnetoelectrics by leveraging the potent effects of magnetostriction.

8.
Hematology ; 29(1): 2377860, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39007733

RESUMO

BACKGROUD: Li-Fraumeni syndrome is a hereditary tumor syndrome characterized by an elevated risk of malignancy, particularly acute lymphoblastic leukemia (ALL), which can be caused by the heterozygous germline mutation. TP53 gene germline mutation is considered a potential risk factor and crucial prognostic parameter for acute leukemia development and diagnosis, but rarely occurs in adults, and its specific pathogenic significance in acute leukemia is unclear. CASE PRESENTATION: We describes a case of a 45-year-old woman diagnosed with ALL. Whole-exome sequencing approach identified one of the TP53 germline mutations from her bone marrow sample with possible pathogenic significance, c.848G>A (p.Arg283His) heterozygous missense mutation located on exon 8, which was further verified in her hair, oral mucous and nail samples. Family pedigree screening revealed that the same TP53 genetic variant was present in the patient's father and non-donor son, whereas not in the donor. Digital PCR observed that this point mutation frequency dropped post-transplantation but remained low during maintenance therapy when the patient was leukemia-free. CONCLUSION: This suspected Li-Fraumeni syndrome case report with a likely pathogenic heterozygous TP53 variant expands the cancer genetic spectrum. Screening her family members for mutations facilitates identifying the optimal relative donor and avoids unnecessary treatment by monitoring TP53 germline mutations for minimal residual disease following hematopoietic stem cell transplantation. Its potential roles in hematological malignant tumor development and clinical pathogenic implications necessitate further probing.


Assuntos
Mutação em Linhagem Germinativa , Síndrome de Li-Fraumeni , Leucemia-Linfoma Linfoblástico de Células Precursoras , Proteína Supressora de Tumor p53 , Humanos , Feminino , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Pessoa de Meia-Idade , Proteína Supressora de Tumor p53/genética , Síndrome de Li-Fraumeni/genética , Síndrome de Li-Fraumeni/diagnóstico , Linhagem
9.
World Neurosurg ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38986944

RESUMO

OBJECTIVE: We designed this study to introduce the surgical strategy cerebrospinal fluid (CSF) decompression in treatment of Chiari malformation type I and compared CSF decompression with other surgical strategies to provide a solid basis for patient counseling. METHODS: The study enrolled 528 consecutive patients with CMI who underwent surgical interventions from 2012 to 2022. The surgical strategy for these patients was bony and dural decompression, anatomical reduction of herniated tonsils, or CSF decompression. Short-term results were determined after 3 months; long-term outcomes were evaluated at last follow-up (at least 18 months). RESULTS: CSF decompression was independently associated with better long- or short-term primary outcomes than anatomical reduction of herniated tonsils or bony and dural decompression (P < 0.001). Compared with short-term, the long-term outcomes were better in patients who underwent CSF decompression (P = 0.035), but were worse in patients with bony and dural decompression (P = 0.03). Specific surgical techniques cannot affect the long- and short-term outcomes of patients with Chiari malformation type I. CSF decompression provided better long-term syringomyelia improvement than short-term (181/218, 83% vs. 169/218, 77.5%; P < 0.001). CONCLUSIONS: CSF decompression, but not a specific surgical technique or operative method, was associated with favorable neurological outcomes in ADULT patients with Chiari malformation type I. The surgical technique and operative method should be selected according to the characteristics of each patient and the intraoperative condition to normalize CSF circulation at the craniovertebral junction area. The intraoperative target, smooth CSF flow out from the fourth ventricle and in to the bilateral Luschka foramina, could be observed.

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