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1.
Theranostics ; 14(7): 2993-3013, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38773972

RESUMO

The sirtuin (SIRT) family is well-known as a group of deacetylase enzymes that rely on nicotinamide adenine dinucleotide (NAD+). Among them, mitochondrial SIRTs (SIRT3, SIRT4, and SIRT5) are deacetylases located in mitochondria that regulate the acetylation levels of several key proteins to maintain mitochondrial function and redox homeostasis. Mitochondrial SIRTs are reported to have the Janus role in tumorigenesis, either tumor suppressive or oncogenic functions. Although the multi-faceted roles of mitochondrial SIRTs with tumor-type specificity in tumorigenesis, their critical functions have aroused a rising interest in discovering some small-molecule compounds, including inhibitors and activators for cancer therapy. Herein, we describe the molecular structures of mitochondrial SIRTs, focusing on elucidating their regulatory mechanisms in carcinogenesis, and further discuss the recent advances in developing their targeted small-molecule compounds for cancer therapy. Together, these findings provide a comprehensive understanding of the crucial roles of mitochondrial SIRTs in cancer and potential new therapeutic strategies.


Assuntos
Mitocôndrias , Neoplasias , Sirtuínas , Sirtuínas/metabolismo , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Carcinogênese/metabolismo , Carcinogênese/efeitos dos fármacos
2.
J Ethnopharmacol ; : 118286, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38723919

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Di-Long (Pheretima vulgaris) is a classic animal sourced traditional Chinese medicine. It has been used for the treatment of joint inflammation and arthralgia for over two thousand years due to its effects of Tong-Luo-Zhi-Tong (dredging collaterals and alleviating pain). Our previous study showed that Chinese medicine Di-Long has significant anti-rheumatoid arthritis (RA) effects. AIM OF THE STUDY: Considering Di-Long as a potential source of active compounds with specific anti-RA therapeutic effects, this research was to obtain the anti-RA target-specific active fraction from Di-Long extracts (DL), and to further explore the chemical basis and verify the anti-RA mechanism of this active fraction. MATERIALS AND METHODS: Transcriptomic was applied to obtain the main anti-RA targets of DL on human RA fibroblast-like synoviocytes (FLS) and validated by qPCR. The target-corresponding active fraction was isolated from DL by ethanol precipitation and gel chromatography, and analyzed by nanoliter chromatography-mass spectrometry. Anti-RA effects of this active fraction was investigated by collagen-induced arthritis (CIA) in mice, and anti-RA mechanisms were verified in cocultured model of rat FLS and peripheral blood lymphocytes. RESULTS: We confirmed that CXCL10/CXCR3 was the main anti-RA target of DL. The active fraction - A (2182 - 890 Da) was isolated from DL based on its CXCL10 inhibiting effects in RA-FLS. Fraction A contains 195 peptides (192 were newly discovered), 26 of which might be bioactive and were considered to be the chemical basis of its anti-RA effects. Fraction A significantly ameliorated the joint destruction and overall inflammation in CIA mice, and downregulated CXCR3 expression in mice joint. Fraction A inhibited the chemotaxis of Th-cells in rat peripheral blood lymphocytes towards the TNF-α-induced rat FLS through CXCL10/CXCR3 pathway. CONCLUSIONS: Our work indicated that active fraction from DL containing small peptides exhibits promising therapeutic effects for RA through inhibiting CXCL10/CXCR3 chemotaxis.

3.
Materials (Basel) ; 17(9)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38730834

RESUMO

This study used DC magnetron sputtering technology to fabricate Sm-Fe films and systematically investigated the phase transition behavior of Sm-Fe films with different Fe ratios. It was found that at higher Fe content, the films consisted of Sm2Fe17 or SmFe7 phases; as Fe content decreased, the films were mainly composed of SmFe3 or SmFe2 phases; at higher Sm content, the films primarily consisted of Sm phase. Sm is prone to volatilization at high temperatures, so Ta was used as a capping layer to effectively suppress Sm volatilization, successfully synthesizing pure SmFe2 phase films at a nearly 1:2 ratio. The magnetic properties and magnetostrictive behavior of the SmFe2 films were investigated, revealing that pure-phase SmFe2 films exhibit good perpendicular magnetic anisotropy and magnetostriction properties. The larger stress along the perpendicular-to-film direction, resulting from the absence of substrate-induced constraints, contributes to the excellent perpendicular magnetic anisotropy of the films. This study successfully synthesized pure-phase SmFe2 films and discovered a new method for fabricating perpendicularly anisotropic films. The research findings are of great significance for the efficient synthesis of desired films with high phase formation temperatures containing volatile elements.

4.
J Thorac Dis ; 16(4): 2236-2243, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38738225

RESUMO

Background: An increasing number of patients with synchronous esophageal cancer (EC) and gastric cancer (GC) have been diagnosed in recent years. Colon or jejunal interposition for esophageal reconstruction has been frequently performed. This study aimed to evaluate the technical feasibility of a new surgical procedure for patients with synchronous thoracic middle-lower segment EC and distal GC. Methods: Between July 2012 and December 2021, 18 patients underwent simultaneous esophagectomy and distal gastrectomy, in which the tubular stomach was formed by greater curvature of proximal stomach, with the right gastroepiploic vessels used as the blood supply. Patient demographics and perioperative data were analyzed. Results: All 18 patients were male, with a mean age of 64.9 years (range, 51-72 years). The mean ± standard deviation (SD) operative duration was 249.6±17.4 min (range, 195-275 min) and mean estimated blood loss was 200.0±86.6 mL (range, 100-400 mL). Ten (55.6%) patients recovered well without any complications, with a mean postoperative length of hospitalization of 9.2±2.6 days (range, 6-13 days). Overall, postoperative complications, defined as Clavien-Dindo grades I-V, occurred in eight (44.4%) patients, with anastomotic leakage in four (22.2%), and hydrothorax (11.1%), gastric retention (5.6%), pneumonia (5.6%), and jaundice (5.6%) occurring in two, one, one, and one patient(s), respectively. All patients who experienced complications recovered after treatment, except for one who died of anastomotic leakage. Conclusions: The surgical procedure might be a new treatment option for selected patients with synchronous thoracic middle-lower segment EC and distal GC.

5.
World J Gastrointest Surg ; 16(4): 1165-1175, 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38690051

RESUMO

BACKGROUND: Crohn's disease (CD) is a chronic inflammatory disease of the gastrointestinal tract, often requiring intestinal resection as a common treatment. However, recurrence after surgery is common. The anastomotic configuration after bowel resection appears to be associated with the recurrence of CD. Previous studies have suggested that the Kono-S anastomosis may help to reduce the recurrence rate. However, the results remain controversial. Therefore, evidence-based evidence is needed to prove the advantages of Kono-S anastomosis. AIM: To measure the influence of anastomosis techniques on the long-term relapse rate of CD by conducting a meta-analysis. METHODS: PubMed, Scopus, and Cochrane Library were searched until October 8, 2023. Patients who underwent intestinal resection due to CD were included. The intervention measures included Kono-S anastomosis, whereas the control group received traditional anastomosis such as end-to-end, end-to-side, and side-to-side anastomosis. Only randomized clinical trials and observational studies were included. The primary outcome measures were hospital stay post-surgery, overall postoperative complication incidence, the proportion of Clavien-Dindo grade IIIa or higher, overall postoperative recurrence rate, and Rutgeerts score. RESULTS: From 2011 to 2023, six articles met the inclusion and exclusion criteria. The results indicated that Kono-S anastomosis can reduce the hospital stay post-surgery of patients with CD [MD = -0.26, 95%CI: -0.42 to -0.10, P = 0.002] than other traditional anastomosis methods. Compared to other traditional anastomosis methods, Kono-S anastomosis can significantly reduce the total recurrence rate [MD = 0.40, 95%CI: 0.17 to 0.98, P = 0.05] and postoperative Rutgeerts score [MD = -0.81, 95%CI: -0.96 to -0.66, P < 0.001] in patients with CD. However, there is no significant disparity in the overall occurrence of postoperative complications and the proportion of Clavien-Dindo ≥ IIIa. CONCLUSION: Kono-S anastomosis has the potential to expedite the recuperation of CD and diminish relapse hazards; however, additional larger trials are necessary to authenticate its effectiveness.

6.
Acta Pharmacol Sin ; 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38698214

RESUMO

The retinoic acid receptor-related orphan receptor γ (RORγ) is regarded as an attractive therapeutic target for the treatment of prostate cancer. Herein, we report the identification, optimization, and evaluation of 1,2,3,4-tetrahydroquinoline derivatives as novel RORγ inverse agonists, starting from high throughput screening using a thermal stability shift assay (TSA). The representative compounds 13e (designated as XY039) and 14a (designated as XY077) effectively inhibited the RORγ transcriptional activity and exhibited excellent selectivity against other nuclear receptor subtypes. The structural basis for their inhibitory potency was elucidated through the crystallographic study of RORγ LBD complex with 13e. Both 13e and 14a demonstrated reasonable antiproliferative activity, potently inhibited colony formation and the expression of AR, AR regulated genes, and other oncogene in AR positive prostate cancer cell lines. Moreover, 13e and 14a effectively suppressed tumor growth in a 22Rv1 xenograft tumor model in mice. This work provides new and valuable lead compounds for further development of drugs against prostate cancer.

7.
Neuroscience ; 549: 42-54, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38729599

RESUMO

Depression, affecting individuals worldwide, is a prevalent mental disease, with an increasing incidence. Numerous studies have been conducted on depression, yet its pathogenesis remains elusive. Recent advancements in research indicate that disturbances in synaptic transmission, synaptic plasticity, and reduced neurotrophic factor expression significantly contribute to depression's pathogenesis. In our study, we utilized adult male C57BL/6J mice. Lipopolysaccharide (LPS) can induce both chronic and acute depression-like symptoms in mice, a widely used model for studying depression associated with inflammation. N-acetylcysteine (NAC) exhibits anti-inflammatory and ameliorative effects on depressive symptoms. This study sought to determine whether NAC use could mitigate inflammatory depressive behavior through the enhancement of synaptic transmission, synaptic plasticity, and increasing levels of brain-derived neurotrophic factor (BDNF). In this study, we discovered that in mice modeled with depression-like symptoms, the expression levels of dendrites, BDNF, and miniature excitatory postsynaptic potential (mEPSC) in glutamatergic neurons, as well as the α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid glutamate receptors (AMPARs) GluA1 and GluA2 subunits, were significantly decreased. These findings suggest an impairment in the synaptic transmission of glutamatergic neurons. Following treatment with NAC, the previously mentioned levels improved, indicating an enhancement in both synaptic transmission and synaptic plasticity. Our results suggest that NAC exerts a protective effect on mouse models of inflammatory depression, potentially through the enhancement of synaptic transmission and plasticity, as well as the restoration of neurotrophic factor expression. These findings offer vital animal experimental evidence supporting NAC's role in mitigating inflammatory depressive behaviors.

8.
NPJ Precis Oncol ; 8(1): 101, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38755255

RESUMO

Immunotherapy, particularly immune checkpoint inhibitors (ICIs), such as anti-programmed death 1/programmed death-ligand 1 (PD-1/PD-L1) therapy, has emerged as a pivotal treatment modality for solid tumors, including recurrent or metastatic nasopharyngeal carcinoma (R/M-NPC). Despite the advancements in the utilization of ICIs, there is still room for further improving patient outcomes. Another promising approach to immunotherapy for R/M-NPC involves adoptive cell therapy (ACT), which aims to stimulate systemic anti-tumor immunity. However, individual agent therapies targeting dendritic cells (DCs) appear to still be in the clinical trial phase. This current review underscores the potential of immunotherapy as a valuable adjunct to the treatment paradigm for R/M-NPC patients. Further research is warranted to enhance the efficacy of immunotherapy through the implementation of strategies such as combination therapies and overcoming immune suppression. Additionally, the development of a biomarker-based scoring system is essential for identifying suitable candidates for precision immunotherapy.

9.
ACS Nano ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38752561

RESUMO

It remains a grand challenge to amplify the chiroptical activity of chiral metal nanoclusters (NCs) although it is desirable for fundamental research and practical application. Herein, we report a strategy of surface/interface solidification (SIS) for enhancing the chiroptical activity of gold NCs. Structural analysis of [Au19(2R,4R/2S,4S-BDPP)6Cl2]3+ (BDPP is 2,4-bis(diphenylphosphino)pentane) clusters reveals that one of the interfacial gold atoms is flexible between two sites and large space is present on the surface, thus hampering chirality transfer from surface chiral ligands to metal core and leading to low chiroptical activity. Following SIS by filling the flexible sites and replacing chlorides with thiolate ligands affords another pair of [Au20(2R,4R/2S,4S-BDPP)6(4-F-C6H4S)2]4+, which shows a more compact and organized structure and thus an almost 40-fold enhancement of chiroptical activity. This work not only provides an efficient approach for amplifying the chiroptical activity of metal nanoclusters but also highlights the significance of achiral components in shaping chiral nanostructures.

10.
Geroscience ; 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38563864

RESUMO

Epidemiological studies report an elevated risk of Parkinson's disease (PD) in patients with type 2 diabetes mellitus (T2DM) that is mitigated in those prescribed dipeptidyl peptidase 4 (DPP-4) inhibitors. With an objective to characterize clinically translatable doses of DPP-4 inhibitors (gliptins) in a well-characterized PD rodent model, sitagliptin, PF-00734,200 or vehicle were orally administered to rats initiated either 7-days before or 7-days after unilateral medial forebrain bundle 6-hydroxydopamine (6-OHDA) lesioning. Measures of dopaminergic cell viability, dopamine content, neuroinflammation and neurogenesis were evaluated thereafter in ipsi- and contralateral brain. Plasma and brain incretin and DPP-4 activity levels were quantified. Furthermore, brain incretin receptor levels were age-dependently evaluated in rodents, in 6-OHDA challenged animals and human subjects with/without PD. Cellular studies evaluated neurotrophic/neuroprotective actions of combined incretin administration. Pre-treatment with oral sitagliptin or PF-00734,200 reduced methamphetamine (meth)-induced rotation post-lesioning and dopaminergic degeneration in lesioned substantia nigra pars compacta (SNc) and striatum. Direct intracerebroventricular gliptin administration lacked neuroprotective actions, indicating that systemic incretin-mediated mechanisms underpin gliptin-induced favorable brain effects. Post-treatment with a threefold higher oral gliptin dose, likewise, mitigated meth-induced rotation, dopaminergic neurodegeneration and neuroinflammation, and augmented neurogenesis. These gliptin-induced actions associated with 70-80% plasma and 20-30% brain DPP-4 inhibition, and elevated plasma and brain incretin levels. Brain incretin receptor protein levels were age-dependently maintained in rodents, preserved in rats challenged with 6-OHDA, and in humans with PD. Combined GLP-1 and GIP receptor activation in neuronal cultures resulted in neurotrophic/neuroprotective actions superior to single agonists alone. In conclusion, these studies support further evaluation of the repurposing of clinically approved gliptins as a treatment strategy for PD.

11.
ACS Appl Mater Interfaces ; 16(15): 18658-18670, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38587811

RESUMO

Three-dimensional (3D)-printed biodegradable polymer scaffolds are at the forefront of personalized constructs for bone tissue engineering. However, it remains challenging to create a biological microenvironment for bone growth. Herein, we developed a novel yet feasible approach to facilitate biomimetic mineralization via self-adaptive nanotopography, which overcomes difficulties in the surface biofunctionalization of 3D-printed polycaprolactone (PCL) scaffolds. The building blocks of self-adaptive nanotopography were PCL lamellae that formed on the 3D-printed PCL scaffold via surface-directed epitaxial crystallization and acted as a linker to nucleate and generate hydroxyapatite crystals. Accordingly, a uniform and robust mineralized layer was immobilized throughout the scaffolds, which strongly bound to the strands and had no effect on the mechanical properties of the scaffolds. In vitro cell culture experiments revealed that the resulting scaffold was biocompatible and enhanced the proliferation and osteogenic differentiation of mouse embryolous osteoblast cells. Furthermore, we demonstrated that the resulting scaffold showed a strong capability to accelerate in vivo bone regeneration using a rabbit bone defect model. This study provides valuable opportunities to enhance the application of 3D-printed scaffolds in bone repair, paving the way for translation to other orthopedic implants.


Assuntos
Osteogênese , Alicerces Teciduais , Camundongos , Animais , Coelhos , Alicerces Teciduais/química , Biomimética , Regeneração Óssea , Poliésteres/química , Engenharia Tecidual , Impressão Tridimensional
12.
Circulation ; 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38557054

RESUMO

BACKGROUND: An imbalance of antiproliferative BMP (bone morphogenetic protein) signaling and proliferative TGF-ß (transforming growth factor-ß) signaling is implicated in the development of pulmonary arterial hypertension (PAH). The posttranslational modification (eg, phosphorylation and ubiquitination) of TGF-ß family receptors, including BMPR2 (bone morphogenetic protein type 2 receptor)/ALK2 (activin receptor-like kinase-2) and TGF-ßR2/R1, and receptor-regulated (R) Smads significantly affects their activity and thus regulates the target cell fate. BRCC3 modifies the activity and stability of its substrate proteins through K63-dependent deubiquitination. By modulating the posttranslational modifications of the BMP/TGF-ß-PPARγ pathway, BRCC3 may play a role in pulmonary vascular remodeling, hence the pathogenesis of PAH. METHODS: Bioinformatic analyses were used to explore the mechanism of BRCC3 deubiquitinates ALK2. Cultured pulmonary artery smooth muscle cells (PASMCs), mouse models, and specimens from patients with idiopathic PAH were used to investigate the rebalance between BMP and TGF-ß signaling in regulating ALK2 phosphorylation and ubiquitination in the context of pulmonary hypertension. RESULTS: BRCC3 was significantly downregulated in PASMCs from patients with PAH and animals with experimental pulmonary hypertension. BRCC3, by de-ubiquitinating ALK2 at Lys-472 and Lys-475, activated receptor-regulated Smad1/5/9 (Smad1/5/9), which resulted in transcriptional activation of BMP-regulated PPARγ, p53, and Id1. Overexpression of BRCC3 also attenuated TGF-ß signaling by downregulating TGF-ß expression and inhibiting phosphorylation of Smad3. Experiments in vitro indicated that overexpression of BRCC3 or the de-ubiquitin-mimetic ALK2-K472/475R attenuated PASMC proliferation and migration and enhanced PASMC apoptosis. In SM22α-BRCC3-Tg mice, pulmonary hypertension was ameliorated because of activation of the ALK2-Smad1/5-PPARγ axis in PASMCs. In contrast, Brcc3-/- mice showed increased susceptibility of experimental pulmonary hypertension because of inhibition of the ALK2-Smad1/5 signaling. CONCLUSIONS: These results suggest a pivotal role of BRCC3 in sustaining pulmonary vascular homeostasis by maintaining the integrity of the BMP signaling (ie, the ALK2-Smad1/5-PPARγ axis) while suppressing TGF-ß signaling in PASMCs. Such rebalance of BMP/TGF-ß pathways is translationally important for PAH alleviation.

13.
iScience ; 27(5): 109617, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38660401

RESUMO

Long-term manned spaceflight and extraterrestrial planet settlement become the focus of space powers. However, the potential influence of closed and socially isolating spaceflight on the brain function remains unclear. A 180-day controlled ecological life support system integrated experiment was conducted, establishing a spaceflight analog environment to explore the effect of long-term socially isolating living. Three crewmembers were enrolled and underwent resting-state fMRI scanning before and after the experiment. We performed both seed-based and network-based analyses to investigate the functional connectivity (FC) changes of the default mode network (DMN), considering its key role in multiple higher-order cognitive functions. Compared with normal controls, the leader of crewmembers exhibited significantly reduced within-DMN and between-DMN FC after the experiment, while two others exhibited opposite trends. Moreover, individual differences of FC changes were further supported by evidence from behavioral analyses. The findings may shed new light on the development of psychological protection for space exploration.

14.
Am J Reprod Immunol ; 91(4): e13847, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38661639

RESUMO

PROBLEM: Polycystic ovary syndrome (PCOS), a prevalent endocrine-metabolic disorder, presents considerable therapeutic challenges due to its complex and elusive pathophysiology. METHOD OF STUDY: We employed three machine learning algorithms to identify potential biomarkers within a training dataset, comprising GSE138518, GSE155489, and GSE193123. The diagnostic accuracy of these biomarkers was rigorously evaluated using a validation dataset using area under the curve (AUC) metrics. Further validation in clinical samples was conducted using PCR and immunofluorescence techniques. Additionally, we investigate the complex interplay among immune cells in PCOS using CIBERSORT to uncover the relationships between the identified biomarkers and various immune cell types. RESULTS: Our analysis identified ACSS2, LPIN1, and NR4A1 as key mitochondria-related biomarkers associated with PCOS. A notable difference was observed in the immune microenvironment between PCOS patients and healthy controls. In particular, LPIN1 exhibited a positive correlation with resting mast cells, whereas NR4A1 demonstrated a negative correlation with monocytes in PCOS patients. CONCLUSION: ACSS2, LPIN1, and NR4A1 emerge as PCOS-related diagnostic biomarkers and potential intervention targets, opening new avenues for the diagnosis and management of PCOS.


Assuntos
Biomarcadores , Mitocôndrias , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares , Síndrome do Ovário Policístico , Humanos , Síndrome do Ovário Policístico/imunologia , Síndrome do Ovário Policístico/metabolismo , Feminino , Biomarcadores/metabolismo , Mitocôndrias/metabolismo , Aprendizado de Máquina , Adulto , Mastócitos/imunologia , Mastócitos/metabolismo
16.
Biomed Pharmacother ; 175: 116664, 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38678966

RESUMO

Mitochondrial dysmorphology/dysfunction follow global cerebral ischemia-reperfusion (GCI/R) injury, leading to neuronal death. Our previous researches demonstrated that Levodopa (L-DOPA) improves learning and memory impairment in GCI/R rats by increasing synaptic plasticity of hippocampal neurons. This study investigates if L-DOPA, used in Parkinson's disease treatment, alleviates GCI/R-induced cell death by enhancing mitochondrial quality. Metabolomics and transcriptomic results showed that GCI/R damage affected the Tricarboxylic acid (TCA) cycle in the hippocampus. The results of this study show that L-DOPA stabilized mitochondrial membrane potential and ultrastructure in hippocampus of GCI/R rats, increased dopamine level in hippocampus, decreased succinic acid level, and stabilized Ca2+ level in CA1 subregion of hippocampus. As a precursor of dopamine, L-DOPA is presumed to improves mitochondrial function in hippocampus of GCI/R rats. However, dopamine cannot cross the blood-brain barrier, so L-DOPA is used in clinical therapy to supplement dopamine. In this investigation, OGD/R models were established in isolated mouse hippocampal neurons (HT22) and primary rat hippocampal neurons. Notably, dopamine exhibited a multifaceted impact, demonstrating inhibition of mitochondrial reactive oxygen species (mitoROS) production, stabilization of mitochondrial membrane potential and Ca2+ level, facilitation of TCA circulation, promotion of aerobic respiratory metabolism, and downregulation of succinic acid-related gene expression. Consistency between in vitro and in vivo results underscores dopamine's significant neuroprotective role in mitigating mitochondrial dysfunction following global cerebral hypoxia and ischemia injury. Supplement dopamine may represent a promising therapy to the cognitive impairment caused by GCI/R injury.

17.
Small Methods ; : e2400040, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38682590

RESUMO

The study of the structures, applications, and structure-property relationships of atomically precise metal nanoclusters relies heavily on their controlled synthesis. Although great progress has been made in the controlled synthesis of Group 11 (Cu, Ag, Au) metal nanoclusters, the preparation of Pd nanoclusters remains a grand challenge. Herein, a new, simple, and versatile synthetic strategy for the controlled synthesis of Pd nanoclusters is reported with tailorable structures and functions. The synthesis strategy involves the controllable transformations of Pd4(CO)4(CH3COO)4 in air, allowing the discovery of a family of Pd nanoclusters with well-defined structure and high yield. For example, by treating the Pd4(CO)4(CH3COO)4 with 2,2-dipyridine ligands, two clusters of Pd4 and Pd10 whose metal framework describes the growth of vertex-sharing tetrahedra have been selectively isolated. Interestingly, chiral Pd4 nanoclusters can be gained by virtue of customized chiral pyridine-imine ligands, thus representing a pioneering example to shed light on the hierarchical chiral nanostructures of Pd. This synthetic methodology also tolerates a wide variety of ligands and affords phosphine-ligated Pd nanoclusters in a simple way. It is believed that the successful exploration of the synthetic strategy would simulate the research enthusiasm on both the synthesis and application of atomically precise Pd nanoclusters.

18.
Molecules ; 29(8)2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38675699

RESUMO

In the face of ongoing water pollution challenges, the intricate interplay between dissolved organic matter and disinfectants like chlorine gives rise to potentially harmful disinfection byproducts (DBPs) during water treatment. The exploration of DBP formation originating from amino acids (AA) is a critical focus of global research. Aromatic DBPs, in particular, have garnered considerable attention due to their markedly higher toxicity compared to their aliphatic counterparts. This work seeks to advance the understanding of DBP formation by investigating chlorination disinfection and kinetics using tyrosine (Tyr), phenylalanine (Phe), and tryptophan (Trp) as precursors. Via rigorous experiments, a total of 15 distinct DBPs with accurate molecular structures were successfully identified. The chlorination of all three AAs yielded highly toxic chlorophenylacetonitriles (CPANs), and the disinfectant dosage and pH value of the reaction system potentially influence chlorination kinetics. Notably, Phe exhibited the highest degradation rate compared to Tyr and Trp, at both the CAA:CHOCl ratio of within 1:2 and a wide pH range (6.0 to 9.0). Additionally, a neutral pH environment triggered the maximal reaction rates of the three AAs, while an acidic condition may reduce their reactivity. Overall, this study aims to augment the DBP database and foster a deeper comprehension of the DBP formation and relevant kinetics underlying the chlorination of aromatic AAs.


Assuntos
Aminoácidos Aromáticos , Desinfecção , Halogenação , Purificação da Água , Cinética , Aminoácidos Aromáticos/química , Purificação da Água/métodos , Desinfetantes/química , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio
19.
J Med Chem ; 67(9): 6952-6986, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38649304

RESUMO

The transcriptional coactivator cAMP response element binding protein (CREB)-binding protein (CBP) and its homologue p300 have emerged as attractive therapeutic targets for human cancers such as acute myeloid leukemia (AML). Herein, we report the design, synthesis, and biological evaluation of a series of cereblon (CRBN)-recruiting CBP/p300 proteolysis targeting chimeras (PROTACs) based on the inhibitor CCS1477. The representative compounds 14g (XYD190) and 14h (XYD198) potently inhibited the growth of AML cells with low nanomolar IC50 values and effectively degraded CBP and p300 proteins in a concentration- and time-dependent manner. Mechanistic studies confirmed that 14g and 14h can selectively bind to CBP/p300 bromodomains and induce CBP and p300 degradation in bromodomain family proteins in a CRBN- and proteasome-dependent manner. 14g and 14h displayed remarkable antitumor efficacy in the MV4;11 xenograft model (TGI = 88% and 93%, respectively). Our findings demonstrated that 14g and 14h are useful lead compounds and deserve further optimization and activity evaluation for the treatment of human cancers.


Assuntos
Antineoplásicos , Proteólise , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Animais , Camundongos , Proteólise/efeitos dos fármacos , Linhagem Celular Tumoral , Proteína p300 Associada a E1A/metabolismo , Proteína p300 Associada a E1A/antagonistas & inibidores , Proteína de Ligação a CREB/metabolismo , Proteína de Ligação a CREB/antagonistas & inibidores , Descoberta de Drogas , Ensaios Antitumorais Modelo de Xenoenxerto , Relação Estrutura-Atividade , Fatores de Transcrição de p300-CBP/metabolismo , Fatores de Transcrição de p300-CBP/antagonistas & inibidores , Proliferação de Células/efeitos dos fármacos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Camundongos Nus
20.
J Med Imaging (Bellingham) ; 11(2): 024010, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38618171

RESUMO

Purpose: Functional magnetic resonance imaging (fMRI) and functional connectivity (FC) have been used to follow aging in both children and older adults. Robust changes have been observed in children, in which high connectivity among all brain regions changes to a more modular structure with maturation. We examine FC changes in older adults after 2 years of aging in the UK Biobank (UKB) longitudinal cohort. Approach: We process fMRI connectivity data using the Power264 atlas and then test whether the average internetwork FC changes in the 2722-subject longitudinal cohort are statistically significant using a Bonferroni-corrected t-test. We also compare the ability of Power264 and UKB-provided, independent component analysis (ICA)-based FC to determine which of a longitudinal scan pair is older. Finally, we investigate cross-sectional FC changes as well as differences due to differing scanner tasks in the UKB, Philadelphia Neurodevelopmental Cohort, and Alzheimer's Disease Neuroimaging Initiative datasets. Results: We find a 6.8% average increase in somatomotor network (SMT)-visual network (VIS) connectivity from younger to older scans (corrected p<10-15) that occurs in male, female, older subject (>65 years old), and younger subject (<55 years old) groups. Among all internetwork connections, the average SMT-VIS connectivity is the best predictor of relative scan age. Using the full FC and a training set of 2000 subjects, one is able to predict which scan is older 82.5% of the time using either the full Power264 FC or the UKB-provided ICA-based FC. Conclusions: We conclude that SMT-VIS connectivity increases with age in the UKB longitudinal cohort and that resting state FC increases with age in the UKB cross-sectional cohort.

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