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1.
J Immunother Cancer ; 12(10)2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39366751

RESUMO

BACKGROUND: In addition to their established action of synthetic lethality in tumor cells, poly(ADP-ribose) polymerase inhibitors (PARPis) also orchestrate tumor immune microenvironment (TIME) that contributes to suppressing tumor growth. However, it remains not fully understood whether and how PARPis trigger tumor-targeting immune responses. METHODS: To decode the immune responses reshaped by PARPis, we conducted T-cell receptor (TCR) sequencing and immunohistochemical (IHC) analyses of paired clinical specimens before and after niraparib monotherapy obtained from a prospective study, as well as ID8 mouse ovarian tumors. To validate the induction of immunogenic cell death (ICD) by PARPis, we performed immunofluorescence/IHC staining with homologous recombination deficiency tumor cells and patient-derived xenograft tumor tissues, respectively. To substantiate that PARPis elicited tumor cell pyroptosis, we undertook comprehensive assessments of the cellular morphological features, cleavage of gasdermin (GSDM) proteins, and activation of TNF-caspase signaling pathways through genetic downregulation/depletion and selective inhibition. We also evaluated the critical role of pyroptosis in tumor suppression and immune activation following niraparib treatment using a syngeneic mouse model with implanting CRISPR/Cas9 edited Gsdme-/ - ID8 tumor cells into C57BL/6 mice. RESULTS: Our findings revealed that PARPis augmented the proportion of neoantigen-recognized TCR clones and TCR clonal expansion, and induced an inflamed TIME characterized by increased infiltration of both innate and adaptive immune cells. This PARPis-strengthened immune response was associated with the induction of ICD, specifically identified as pyroptosis, which possessed distinctive morphological features and GSDMD/E cleavage. It was validated that the cleavage of GSDMD/E was due to elevated caspase 8 activity downstream of the TNFR1, rather than FAS and TRAIL-R. On PARP inhibition, the NF-κB signaling pathway was activated, leading to increased secretion of TNF-α and subsequent initiation of the TNFR1-caspase 8 cascade. Impeding pyroptosis through the depletion of Gsdme significantly compromised the tumor-suppressing effects of PARP inhibition and undermined the anti-immune response in the syngeneic ID8 mouse model. CONCLUSIONS: PARPis induce a specific type of ICD called pyroptosis via TNF-caspase 8-GSDMD/E axis, resulting in an inflamed TIME and augmentation of tumor-targeting immune responses. These findings deepen our understanding of PARPis activities and point toward a promising avenue for synergizing PARPis with immunotherapeutic interventions. TRIAL REGISTRATION NUMBER: NCT04507841.


Assuntos
Neoplasias Ovarianas , Inibidores de Poli(ADP-Ribose) Polimerases , Piroptose , Animais , Feminino , Humanos , Camundongos , Linhagem Celular Tumoral , Gasderminas , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/imunologia , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Proteínas de Ligação a Fosfato/metabolismo , Piperidinas/farmacologia , Piperidinas/uso terapêutico , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Piroptose/efeitos dos fármacos , Transdução de Sinais , Microambiente Tumoral , Fator de Necrose Tumoral alfa/metabolismo
2.
Nat Commun ; 15(1): 8560, 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39362874

RESUMO

CRISPR diagnostics are effective but suffer from low signal transduction efficiency, limited sensitivity, and poor stability due to their reliance on the trans-cleavage of single-stranded nucleic acid fluorescent reporters. Here, we present CrisprAIE, which integrates CRISPR/Cas reactions with "one to more" aggregation-induced emission luminogen (AIEgen) lighting-up fluorescence generated by the trans-cleavage of Cas proteins to AIEgen-incorporated double-stranded DNA labeled with single-stranded nucleic acid linkers and Black Hole Quencher groups at both ends (Q-dsDNA/AIEgens-Q). CrisprAIE demonstrates superior performance in the clinical nucleic acid detection of norovirus and SARS-CoV-2 regardless of amplification. Moreover, the diagnostic potential of CrisprAIE is further enhanced by integrating it with spherical nucleic acid-modified AIEgens (SNA/AIEgens) and a portable cellphone-based readout device. The improved CrisprAIE system, utilizing Q-dsDNA/AIEgen-Q and SNA/AIEgen reporters, exhibits approximately 80- and 270-fold improvements in sensitivity, respectively, compared to conventional CRISPR-based diagnostics. We believe CrisprAIE can be readily extended as a universal signal generation strategy to significantly enhance the detection efficiency of almost all existing CRISPR-based diagnostics.


Assuntos
Sistemas CRISPR-Cas , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Norovirus/genética , COVID-19/virologia , DNA/genética , Corantes Fluorescentes/química
3.
Med Rev (2021) ; 4(5): 395-412, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39444798

RESUMO

Dyspnea is a subjective sensation often described as a feeling of respiratory effort, tightness, or air hunger. The underlying mechanisms of this symptom are multifaceted and involve factors such as respiratory centers, cardiovascular system, airways, neuromuscular components, and metabolic factors, although not fully elucidated. The classical theory of imbalance between inspiratory neural drive (IND) and the simultaneous dynamic responses of the respiratory system posits that the disruption of a normal and harmonious relationship fundamentally shapes the expression of respiratory discomfort. Assessment and comprehensive treatment of dyspnea are crucial for patient rehabilitation, including subjective self-reporting and objective clinical measurements. Non-pharmacological interventions, such as pulmonary rehabilitation, fan therapy, exercise, chest wall vibration, virtual reality technology, traditional Chinese medicine (acupuncture and acupressure), and yoga, have shown promise in alleviating dyspnea symptoms. Additionally, oxygen therapy, has demonstrated short-term benefits for patients with pre-hospital respiratory distress and hypoxemia. This review provides a comprehensive overview of dyspnea, emphasizing the importance of a multifaceted approach for its assessment and management, with a focus on non-pharmacological interventions that contribute to enhanced patient outcomes and quality of life.

4.
J Thorac Dis ; 16(9): 5727-5741, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39444878

RESUMO

Background: Lung transplantation (LTx) is a well-established option for patients in the end-stage of lung disease that is not responsive to other treatments. Although the survival rate after LTx has seen a significant increase, exercise tolerance is still limited and poses a big obstacle to recovery after LTx. Pulmonary rehabilitation (PR) is a comprehensive intervention that has many benefits for patients with chronic respiratory disease. However, the effectiveness of PR on adult patients with LTx is inconclusive. We performed this meta-analysis to assess the efficacy of PR in adult LTx recipients. Methods: Eligible randomized controlled trials (RCTs) and quasi-experimental studies published until March 25, 2024 were searched in MEDLINE, Embase, Web of Science and CINAHL. Additionally, reference lists and published systematic reviews were scanned by manual searching. Studies selection, data extraction, and risk of bias assessment were conducted independently. Stata software (version 17.0) was utilized. Results: There were 21 studies (9 RCTs and 12 quasi-experimental studies) were identified. Pooled analysis showed that PR positive effect in improving 6-minute walking distance (6MWD) [standard mean difference (SMD) =1.28, 95% confidence interval (CI): 1.05-1.50, P<0.001], maximum oxygen consumption (VO2max) (SMD =0.42, 95% CI: 0.15-0.68, P=0.002), handgrip force (HGF) (SMD =0.49, 95% CI: 0.26-0.73, P<0.001), and quadriceps force (QF) (SMD =0.63, 95% CI: 0.45-0.82, P<0.001). There was no significant publication bias in those outcomes mentioned above. Conclusions: PR shows evidence for being an effective adjunctive strategy for improving exercise capacity after LTx, but multi-center trials on larger populations are required to confirm its clinical benefits in the real-world setting.

5.
Ecotoxicol Environ Saf ; 286: 117237, 2024 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-39447297

RESUMO

Micro/nanoplastics (MNPs) and heavy metals (HMs) coexist worldwide. Existing studies have reported different or even contradictory toxic effects of co-exposure to MNPs and HMs on plants, which may be related to various influencing factors. In this study, existing publications were searched and analyzed using CiteSpace, meta-analysis, and machine learning. CiteSpace analysis showed that this research field was still in the nascent stage, and hotspots in this field included accumulation, cadmium (Cd), growth, and combined toxicity. Meta-analysis revealed the differential association of seven influencing factors (MNP size, pollutant treatment duration, cultivation media, plant species, MNP type, HM concentration, and MNP concentration) and 8 physiological parameters receiving the most attention. Co-exposure of the two contaminants had stronger toxic effects than HM treatment alone, and phytotoxicity was generally enhanced with increasing concentrations and longer exposure durations, especially when using nanoparticles, hydroponic medium, dicotyledons producing stronger toxic effects than microplastics, soil-based medium, and monocotyledons. Dry and fresh weight analysis showed that co-exposure to MNPs and Cd resulted in significant phytotoxicity in all classifications. Concerning the MNP types, polyolefins partially attenuated plant toxicity, but both modified polystyrene (PS) and biodegradable polymers exacerbated joint phytotoxicity. Finally, machine learning was used to fit and predict plant HM concentrations, showing five classifications with an accuracy over 80 %, implying that the polynomial regression model could be used to predict HM content in plants under complex pollution conditions. Overall, this study identifies current knowledge gaps and provides guidance for future research.

6.
RSC Adv ; 14(45): 32992-33006, 2024 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-39429927

RESUMO

Overbased sulfonate plays a crucial role in calcium sulfonate complex grease, significantly impacting the grease's performance characteristics. Herein, the calcium sulfonate complex grease was formulated using overbased calcium sulfonate (T106D) and overbased magnesium sulfonate (T107) in ratios of 1 : 2, 1 : 1, and 2 : 1, labeled as CMSCG (1 : 2), CMSCG (1 : 1), and CMSCG (2 : 1), respectively. This study examined the effects of overbased sulfonates on the physicochemical, anti-corrosion, rheological, and tribological properties of the grease. Results showed that CMSCG (1 : 2) exhibited superior physicochemical properties, with the highest dropping point (354 °C), the lowest penetration (161 (0.1 mm)), and the least oil separation (1.25%). Exposure to a salt spray environment significantly altered the grease's rheological properties. The combination of T106D and T107 enhanced the corrosion resistance of the grease, attributed to the formation of a corrosion inhibition layer. Incorporating T107 increased both the yield stress and hysteresis area of the calcium sulfonate complex grease. The CMSCG (1 : 2), CMSCG (1 : 1), and MSCG showed the high thixotropic ring area, indicating the poor thixotropy. The calcium sulfonate complex grease formulated with T107 showed the highest yield stress (558 Pa). The friction mechanism revealed that MSCG showed the optimal friction reduction properties, and CMSCG (1 : 1) demonstrated the optimal wear resistance, which are attributed to the synergistic effects of tribo-chemical films composed of CaO, CaCO3, FeSO4, MgCO3, and iron oxide.

7.
Apoptosis ; 2024 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-39394530

RESUMO

Myocardial fibrosis is a typical pathological manifestation of hypertension. However, the exact role of sirtuin 7 (SIRT7) in myocardial remodeling remains largely unclear. Here, spontaneously hypertensive rats (SHRs) and angiotensin (Ang) II-induced hypertensive mice were pretreated with recombinant adeno-associated virus (rAAV)-SIRT7, copper chelator tetrathiomolybdate (TTM) or copper ionophore elesclomol, respectively. Compared with normotensive controls, reduced SIRT7 expression and augmented cuproptosis were observed in hearts of hypertensive rats and mice with decreased FDX1 levels and increased HSP70 levels. Notably, intervention with rAAV-SIRT7 and TTM strikingly prevented DLAT oligomers aggregation, and elevated ATP7A and TOM20 expressions, contributing to the alleviation of cuproptosis, mitochondrial injury, myocardial remodeling and heart dysfunction in spontaneously hypertensive rats and Ang II-induced hypertensive mice. In cultured rat primary cardiac fibroblasts (CFs), rhSIRT7 alleviated CuCl2, Ang II or elesclomol-induced cuproptosis and fibroblast activation by blunting DLAT oligomers accumulation and downregulating α-SMA expression. Additionally, conditioned medium from rhSIRT7-pretreated CFs remarkably mitigated cellular hypertrophy and mitochondrial impairments of neonatal rat cardiomyocytes, as well as cell migration and polarization of RAW 264.7 macrophages. Importantly, verteporfin reduced CuCl2-induced cuproptosis, mitochondrial injury and fibrotic activation in CFs. Knockdown of ATP7A with si-ATP7A blocked cellular protective effects of rhSIRT7 and verteporfin in CFs. In conclusion, SIRT7 attenuates cuproptosis, myocardial fibrosis and heart dysfunction in hypertension through the modulation of YAP/ATP7A signaling. Targeting SIRT7 is of vital importance for developing therapeutic strategies in hypertension and hypertensive heart disorders.

8.
Pest Manag Sci ; 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39387718

RESUMO

BACKGROUND: Pospiviroids, members of the genus Pospiviroid, can cause severe diseases in tomato and other Solanaceae crops, causing considerable economic losses worldwide. Six pospiviroids including potato spindle tuber viroid (PSTVd), tomato chlorotic dwarf viroid (TCDVd), tomato planta macho viroid (TPMVd), Columnea latent viroid (CLVd), pepper chat fruit viroid (PCFVd), and tomato apical stunt viroid (TASVd) are regulated in many countries and organizations. Rapid, accurate detection is thus crucial for controlling the spread of these pospiviroids. RESULTS: For simultaneous detection of these six pospiviroids, we developed a rapid, visual method that uses a reverse transcription recombinase-aided amplification (RT-RAA) assay coupled with a clustered regularly interspaced short palindromic repeats and CRISPR-associated protein 12a (CRISPR/Cas12a) system. In particular, this technique could achieve both universal detection and specific identification of the six target pospiviroids within 40 min. The universal detection could diagnose the six target pospiviroids in a single reaction, and the specific identification could identify each target pospiviroid without cross-reactivity of other pospiviroids. The sensitivity limits for the target pospiviroids detection with the proposed detection method were higher than those of the conventional reverse transcription-polymerase chain reaction (RT-PCR) method. CONCLUSION: We designed an RT-RAA-CRISPR/Cas12a-based universal detection method for both large-scale screening and accurate identification of the six target pospiviroids, which is appropriate for on-site detection. Our study results can aid in performing rapid, large-scale screening of multiple pests simultaneously. © 2024 Society of Chemical Industry.

9.
Clin Mol Hepatol ; 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39406379

RESUMO

Background: Early detection and effective prognosis prediction in patients with hepatocellular carcinoma (HCC) provides an avenue for survival improvement, yet more effective approaches are greatly needed. We sought to develop the detection and prognosis models with ultra-sensitivity and low cost based on fragmentomic features of circulating cell free mtDNA (ccf-mtDNA). Participants and methods: Capture-based mtDNA sequencing was carried out in plasma cell-free DNA samples from 1168 participants, including 571 patients with HCC, 301 patients with chronic hepatitis B or liver cirrhosis (CHB/LC) and 296 healthy controls (HC). Results: The systematic analysis revealed significantly aberrant fragmentomic features of ccf-mtDNA in HCC group when compared with CHB/LC and HC groups. Moreover, we constructed a random forest algorithm-based HCC detection model by utilizing ccf-mtDNA fragmentomic features. Both internal and two external validation cohorts demonstrated the excellent capacity of our model in distinguishing early HCC patients from HC and high-risk population with CHB/LC, with AUC exceeding 0.983 and 0.981, sensitivity over 89.6% and 89.61%, and specificity over 98.20% and 95.00%, respectively, greatly surpassing the performance of alpha-fetoprotein (AFP) and mtDNA copy number. We also developed a HCC prognosis prediction model by LASSO-Cox regression to select 20 fragmentomic features, which exhibited exceptional ability in predicting 1-year, 2-year and 3-year survival (AUC = 0.8333, 0.8145 and 0.7958 for validation cohort, respectively). Conclusions: We have developed and validated a high-performing and low-cost approach in a large clinical cohort based on aberrant ccf-mtDNA fragmentomic features with promising clinical translational application for the early detection and prognosis prediction of HCC patients.

10.
Artigo em Inglês | MEDLINE | ID: mdl-39428600

RESUMO

The inherent challenges associated with aqueous zinc ion batteries (AZIBs), such as low energy density and slow diffusion kinetics, pose significant obstacles to their widespread adoption as energy storage systems. These limitations mainly stem from the nongreen and complex preparation process of high-quality cathode materials. In this study, we propose an approach utilizing microwave-assisted ball milling to expedite the fabrication of vanadium-based intercalated nanomaterials, aiming at solving the problem of prolonged reaction at high temperatures, which is unavoidable in the preparation of anode materials. Na2V6O16 (NVO) nanorods were synthesized in just 40 min under aqueous solvent conditions. These nanorods exhibit remarkable electrochemical properties, including a high specific capacity of 564 mA h g-1 at 0.1 A g-1 and an excellent cycle life, maintaining 164.2 mA h g-1 after 5000 cycles at 5 A g-1. Additionally, the incorporation of Na+ into the electrolyte effectively mitigates the stripping of Na+ and the deposition of Zn dendrimers from NVO, further contributing to enhanced cycling stability. The findings of this study offer a promising approach to the rapid and efficient synthesis of high-quality ZIB cathode materials.

11.
Ann Surg ; 2024 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-39431564

RESUMO

OBJECTIVE: This study aimed to investigate the prevalence and distribution of carcinoma in the liver margin (LM) of resected perihilar cholangiocarcinoma (pCCA) and establish a method for LM examination. BACKGROUND: LM is the largest margin in resected pCCA with undefined status and assessment method. METHODS: 227 pCCA cases underwent major hepatectomy were divided into a discovery cohort (n=101) assessed using serial whole-mount digital large sections (WDLS) combined with small sections, and a control cohort (n=126) assessed using only small sections. RESULTS: The LM R1 resection rate was 38.6% (39/101) in the discovery cohort and 5.6% (7/126) in the control cohort. WDLS identified more LM R1 cases compared to the small section in the discovery cohort (38.6% vs. 5.9%, P<0.001). R0 patients in the discovery cohort had better overall survival and recurrence-free survival than those in the control cohort (both P<0.05). Additionally, 95% of carcinoma was found within 20 mm of the proximal ductal margin (DM). A proximal DM distance of<5 mm was an independent risk factor for LM R1 resection. Patients with which are more likely to experience R1 compared to those with ≥ 5 mm (P<0.001). CONCLUSIONS: Positive LM was the significant cause for R1 resection of pCCA and the utilization of WDLS improved the diagnostic accuracy of LM. An examination methodology was established, highlighting the necessity of examining LM within a 20 mm radius around the proximal DM, especially in patients with a proximal DM of<5 mm.

12.
ACS Nano ; 2024 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-39423317

RESUMO

Photodynamic therapy (PDT) has emerged as a preferred nonsurgical treatment in clinical applications due to its capacity to selectively eradicate diseased tissues while minimizing damage to normal tissue. Nevertheless, its clinical efficacy is constrained by the limited penetration of visible light. Although near-infrared (NIR) lasers offer enhanced tissue penetration, the dearth of suitable photosensitizers and a pronounced imaging-treatment disparity pose challenges. Additionally, clinical implementation via optical fiber implantation carries infection risks and necessitates minimally invasive surgery, contradicting PDT's noninvasive advantage. In this study, we introduce a brilliant approach utilizing aggregation-induced emission luminogens (AIEgen) to develop a visible-light penetrator (VLP), coupled with wireless light emitting diodes (LEDs), enabling deep photodynamic therapy. We validate the therapeutic efficacy of this visible-light penetrator in tissues inaccessible to conventional PDT, demonstrating significant suppression of inflammatory diffusion in vivo using AIEgen TBPPM loaded within the VLP, which exhibits a transmittance of 86% in tissues with a thickness of 3 mm. This innovative visible-light penetrator effectively overcomes the substantial limitations of PDT in clinical settings and holds promise for advancing phototherapy.

13.
Chembiochem ; : e202400685, 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39317648

RESUMO

Photoactivable CRISPR technology represents a transformative approach in the field of genome editing, offering unprecedented control over gene editing with high spatial and temporal precision. By harnessing the power of light to modulate the activity of CRISPR components, this innovative strategy enables precise regulation of Cas proteins, guide RNAs, and ribonucleoprotein complexes. Recent advancements in optical control methodologies, including the development of photoactivable nanocarriers, have significantly expanded the potential applications of CRISPR in biomedical fields. This Concept highlights the latest developments in designing photoactivable CRISPR systems and their promising applications in biosensing and cancer therapy. Additionally, the remaining challenges and future trends are also discussed. It is expected that the photoactivable CRISPR would facilitate translating more precise gene therapies into clinical use.

14.
Angew Chem Int Ed Engl ; : e202414340, 2024 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-39305151

RESUMO

The bisbenzylisoquinoline alkaloids (bisBIAs) have attracted tremendous attention from the synthetic community due to their diverse and intriguing biological activities. Herein, we report the convergent and modular chemoenzymatic syntheses of eight bisBIAs bearing various substitutes and linkages in 5-7 steps. The gram-scale synthesis of various well-designed enantiopure benzylisoquinoline monomers was accomplished via an enzymatic stereoselective Pictet-Spengler reaction, followed by regioselective enzymatic methylation or chemical functionalizations in a sequential one-pot process. A modified intermolecular copper-mediated Ullmann coupling enabled the concise and efficient total synthesis of five different linear bisBIAs with either head-to-tail or tail-to-tail linkage.  A biomimetic oxidative phenol dimerization selectively formed the sterically hindered, electron-rich diaryl ether bond, and subsequent intramolecular Suzuki-Miyaura domino reaction or Ullmann coupling facilitated the first enantioselective total synthesis of three macrocyclic bisBIAs, including ent-isogranjine, tetrandrine and O-methylrepandine. This study highlights the great potential of chemoenzymatic strategies in the total synthesis of diverse bisBIAs and paves the way to further explore the biological functions of these natural products.

15.
J Mol Med (Berl) ; 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39287635

RESUMO

Circular RNAs (circRNAs) are an interesting class of conserved single-stranded RNA molecules derived from exon or intron sequences produced by the reverse splicing of precursor mRNA. CircRNAs play important roles as microRNA sponges, gene splicing and transcriptional regulators, RNA-binding protein sponges, and protein/peptide translation factors. Abnormal functions of circRNAs and RBPs in tumor progression have been widely reported. Insulin-like growth factor-2 mRNA-binding proteins (IGF2BPs) are a highly conserved family of RBPs identified in humans that function as post-transcriptional fine-tuners of target transcripts. Emerging evidence suggests that IGF2BPs regulate the processing and metabolism of RNA, including its stability, translation, and localization, and participate in a variety of cellular functions and pathophysiology. In this review, we have summarized the roles and molecular mechanisms of circRNAs and IGF2BPs in cancer development and progression. In addition, we briefly introduce the role of other RNAs and IGF2BPs in cancer, discuss the current clinical applications and challenges faced by circRNAs and IGF2BPs, and propose future directions for this promising research field.

16.
J Clin Transl Hepatol ; 12(9): 792-801, 2024 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-39280065

RESUMO

Bile acids are byproducts of cholesterol metabolism in the liver and constitute the primary components of bile. Disruption of bile flow leads to cholestasis, characterized by the accumulation of hydrophobic bile acids in the liver and bloodstream. Such accumulation can exacerbate liver impairment. This review discussed recent developments in understanding how bile acids contribute to liver damage, including disturbances in mitochondrial function, endoplasmic reticulum stress, inflammation, and autophagy dysfunction. Mitochondria play a pivotal role in cholestatic liver injury by influencing hepatocyte apoptosis and inflammation. Recent findings linking bile acids to liver damage highlight new potential treatment targets for cholestatic liver injury.

17.
Proc Natl Acad Sci U S A ; 121(39): e2401975121, 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39284062

RESUMO

While the dominant role of halogens in Arctic ozone loss during spring has been widely studied in the last decades, the impact of sea-ice halogens on surface ozone abundance over the northern hemisphere (NH) mid-latitudes remains unquantified. Here, we use a state-of-the-art global chemistry-climate model including polar halogens (Cl, Br, and I), which reproduces Arctic ozone seasonality, to show that Arctic sea-ice halogens reduce surface ozone in the NH mid-latitudes (47°N to 60°N) by ~11% during spring. This background ozone reduction follows the southward export of ozone-poor and halogen-rich air masses from the Arctic through polar front intrusions toward lower latitudes, reducing the springtime tropospheric ozone column within the NH mid-latitudes by ~4%. Our results also show that the present-day influence of Arctic halogens on surface ozone destruction is comparatively smaller than in preindustrial times driven by changes in the chemical interplay between anthropogenic pollution and natural halogens. We conclude that the impact of Arctic sea-ice halogens on NH mid-latitude ozone abundance should be incorporated into global models to improve the representation of ozone seasonality.

18.
mSystems ; 9(10): e0115224, 2024 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-39315778

RESUMO

Trichodesmium, a globally significant N2-fixing marine cyanobacterium, forms extensive surface blooms in nutrient-poor ocean regions. These blooms consist of a dynamic assemblage of Trichodesmium species that form distinct colony morphotypes and are inhabited by diverse microorganisms. Trichodesmium colony morphotypes vary in ecological niche, nutrient uptake, and organic molecule release, differentially impacting ocean carbon and nitrogen biogeochemical cycles. Here, we assessed the poorly studied spatial abundance of metabolites within and between three morphologically distinct Trichodesmium colonies collected from the Red Sea. We also compared these results with two morphotypes of the cultivable Trichodesmium strain IMS101. Using matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI) coupled with liquid extraction surface analysis (LESA) tandem mass spectrometry (MS2), we identified and localized a wide range of small metabolites associated with single-colony Trichodesmium morphotypes. Our untargeted MALDI-MSI approach revealed 80 unique features (metabolites) shared between Trichodesmium morphotypes. Discrimination analysis showed spatial variations in 57 shared metabolites, accounting for 62% of the observed variation between morphotypes. The greatest variations in metabolite abundance were observed between the cultured morphotypes compared to the natural colony morphotypes, suggesting substantial differences in metabolite production between the cultivable strain IMS101 and the naturally occurring colony morphotypes that the cultivable strain is meant to represent. This study highlights the variations in metabolite abundance between natural and cultured Trichodesmium morphotypes and provides valuable insights into metabolites common to morphologically distinct Trichodesmium colonies, offering a foundation for future targeted metabolomic investigations.IMPORTANCEThis work demonstrates that the application of spatial mass spectrometry imaging at single-colony resolution can successfully resolve metabolite differences between natural and cultured Trichodesmium morphotypes, shedding light on their distinct biochemical profiles. Understanding the morphological differences between Trichodesmium colonies is crucial because they impact nutrient uptake, organic molecule production, and carbon and nitrogen export, and subsequently influence ocean biogeochemical cycles. As such, our study serves as an important initial assessment of metabolite differences between distinct Trichodesmium colony types, identifying features that can serve as ideal candidates for future targeted metabolomic studies.


Assuntos
Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Trichodesmium , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Trichodesmium/metabolismo
19.
Bioorg Chem ; 153: 107826, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39299177

RESUMO

Receptor activator of nuclear factor-κB ligand (RANKL) is considered the principal regulator of osteoclast differentiation. Therefore, strategies interfering with the RANKL-RANK signaling pathway may effectively inhibit osteoclast differentiation and mitigate bone resorption. Consequently, RANKL has become a promising target for new drug design strategies. Despite extensive research on specific drugs and antibodies, only a few have shown efficacy in treating osteoporosis. To address this challenge, we aimed to explore new approaches for designing drugs for osteoporosis. In this study, a 3D quantitative structure-activity relationship (QSAR) pharmacophore model was built for RANKL with reference to known inhibitor IC50 values. The optimal pharmacophore model was then employed as a 3D query to screen databases for novel lead compounds. The obtained compounds were subjected to ADMET and TOPKAT analyses to predict drug pharmacokinetics and toxicity. Molecular docking and de novo evolution approaches were applied to verify the docking binding affinities of the compounds. Five candidate compounds were subjected to further in vitro analyses to assess their anti-osteoporotic effects, among which compound 4 demonstrated significant inhibitory activity, achieving an inhibitory rate of 92.6 % on osteoclastogenesis at a concentration of 10 µM. Subsequent molecular dynamics (MD) simulations to assess the stability and behavior of compound 4 and its evolved variant, ZINC00059014397_Evo, within the RANKL binding site revealed that the variant is a potential therapeutic agent for targeting osteoclasts. This study offers valuable insights for developing next generation RANKL inhibitors for osteoporosis treatments.

20.
Animals (Basel) ; 14(17)2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39272322

RESUMO

The aim of this experiment was to investigate the differences in metabolites in perirenal fat (PF) between Chinese Simmental cattle and Angus cattle. Six healthy 18-month-old male Angus cattle and Chinese Simmental cattle were selected, and the perirenal adipose tissue was collected after slaughtering. HE staining, a triglyceride assay kit, and liquid chromatography-tandem mass spectrometry (LC-MS/MS) technology were used to compare and analyze the differences in the cell morphology, lipid accumulation, and metabolites of the two types of PF. The results showed that the PF of Angus cattle had a larger cell area and stronger lipid deposition ability than that of Simmental cattle. A total of 567 metabolites were detected by LC-MS/MS technology, of which 119 were significantly upregulated in Angus cattle PF and 129 were significantly upregulated in Simmental cattle PF. Differential metabolites were enriched in pathways such as fatty acid biosynthesis, polyunsaturated fatty acid biosynthesis, regulation of adipocyte lipolysis, and oxidative phosphorylation. Finally, 12 metabolites that may cause phenotypic differences between the two types of perirenal adipose tissue were screened out from these pathways. This study has preliminarily screened out biomarkers that may affect lipid metabolism in PF, providing basic data for the further exploration of the metabolic characteristics of PF.

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