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1.
Res Sq ; 2024 May 20.
Article in English | MEDLINE | ID: mdl-38826349

ABSTRACT

The reversal of ubiquitination induced by members of the SidE effector family of Legionella pneumophila produces phosphoribosyl ubiquitin (PR-Ub) that is potentially detrimental to host cells. Here we show that the effector LnaB functions to transfer the AMP moiety from ATP to the phosphoryl moiety of PR-Ub to convert it into ADP-ribosylated ubiquitin (ADPR-Ub), which is further processed to ADP-ribose and functional ubiquitin by the (ADP-ribosyl)hydrolase MavL, thus maintaining ubiquitin homeostasis in infected cells. Upon being activated by Actin, LnaB also undergoes self-AMPylation on tyrosine residues. The activity of LnaB requires a motif consisting of Ser, His and Glu (S-HxxxE) present in a large family of toxins from diverse bacterial pathogens. Our study not only reveals intricate mechanisms for a pathogen to maintain ubiquitin homeostasis but also identifies a new family of enzymes capable of protein AMPylation, suggesting that this posttranslational modification is widely used in signaling during host-pathogen interactions.

2.
Cell Mol Life Sci ; 81(1): 249, 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38836877

ABSTRACT

Protein ubiquitination is one of the most important posttranslational modifications (PTMs) in eukaryotes and is involved in the regulation of almost all cellular signaling pathways. The intracellular bacterial pathogen Legionella pneumophila translocates at least 26 effectors to hijack host ubiquitination signaling via distinct mechanisms. Among these effectors, SidC/SdcA are novel E3 ubiquitin ligases with the adoption of a Cys-His-Asp catalytic triad. SidC/SdcA are critical for the recruitment of endoplasmic reticulum (ER)-derived vesicles to the Legionella-containing vacuole (LCV). However, the ubiquitination targets of SidC/SdcA are largely unknown, which restricts our understanding of the mechanisms used by these effectors to hijack the vesicle trafficking pathway. Here, we demonstrated that multiple Rab small GTPases and target soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNARE) proteins are bona fide ubiquitination substrates of SidC/SdcA. SidC/SdcA-mediated ubiquitination of syntaxin 3 and syntaxin 4 promotes their unconventional pairing with the vesicle-SNARE protein Sec22b, thereby contributing to the membrane fusion of ER-derived vesicles with the phagosome. In addition, our data reveal that ubiquitination of Rab7 by SidC/SdcA is critical for its association with the LCV membrane. Rab7 ubiquitination could impair its binding with the downstream effector Rab-interacting lysosomal protein (RILP), which partially explains why LCVs avoid fusion with lysosomes despite the acquisition of Rab7. Taken together, our study reveals the biological mechanisms employed by SidC/SdcA to promote the maturation of the LCVs.


Subject(s)
Legionella pneumophila , Phagosomes , SNARE Proteins , Ubiquitination , rab GTP-Binding Proteins , Legionella pneumophila/metabolism , Humans , Phagosomes/metabolism , Phagosomes/microbiology , SNARE Proteins/metabolism , rab GTP-Binding Proteins/metabolism , Bacterial Proteins/metabolism , Bacterial Proteins/genetics , Animals , Qa-SNARE Proteins/metabolism , Ubiquitin-Protein Ligases/metabolism , Ubiquitin-Protein Ligases/genetics , Vacuoles/metabolism , Vacuoles/microbiology , HEK293 Cells , Mice , rab7 GTP-Binding Proteins/metabolism , Monomeric GTP-Binding Proteins/metabolism , Endoplasmic Reticulum/metabolism
3.
Opt Lett ; 49(10): 2813-2816, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38748168

ABSTRACT

This work proposes and investigates a bent multimode-no-core-multimode optical fiber structure for vector magnetic field sensing applications. The bent no-core fiber (NCF) serves as the sensing area, and the gold film is deposited on its surface to excite the surface plasmon resonance effect. Due to the strong evanescent field of the unclad and bent NCF, the as-fabricated sensor exhibits a high sensitivity of 5630 nm/RIU in the refractive index range of 1.36-1.39. Magnetic fluid is employed as the magneto-sensitive material for magnetic field sensing, exhibiting a high magnetic field intensity sensitivity of 5.74 nm/mT and a high magnetic field direction sensitivity of 0.22 nm/°. The proposed sensor features a simple structure, low cost, point sensing, and excellent mechanical performance.

4.
BMC Nurs ; 23(1): 320, 2024 May 11.
Article in English | MEDLINE | ID: mdl-38734605

ABSTRACT

BACKGROUND: Chemotherapy, whilst treating tumours, can also lead to numerous adverse reactions such as nausea and vomiting, fatigue and kidney toxicity, threatening the physical and mental health of patients. Simultaneously, misuse of chemotherapeutic drugs can seriously endanger patients' lives. Therefore, to maintain the safety of chemotherapy for cancer patients and to reduce the incidence of adverse reactions to chemotherapy, many guidelines state that a comprehensive assessment of the cancer patient should be conducted and documented before chemotherapy. This recommended procedure, however, has yet to be extensively embraced in Chinese hospitals. As such, this study aimed to standardise the content of pre-chemotherapy assessment for cancer patients in hospitals and to improve nurses' adherence to pre-chemotherapy assessment of cancer patients by conducting a national multi-site evidence implementation in China, hence protecting the safety of cancer patients undergoing chemotherapy and reducing the incidence of adverse reactions to chemotherapy in patients. METHODS: The national multi-site evidence implementation project was launched by a JBI Centre of Excellence in China and conducted using the JBI approach to evidence implementation. A pre- and post-audit approach was used to evaluate the effectiveness of the project. This project had seven phases: training, planning, baseline audit, evidence implementation, two rounds of follow-up audits (3 and 9 months after evidence implementation, respectively) and sustainability assessment. A live online broadcast allowed all participating hospitals to come together to provide a summary and feedback on the implementation of the project. RESULTS: Seventy-four hospitals from 32 cities in China participated in the project, four withdrew during the project's implementation, and 70 hospitals completed the project. The pre-and post-audit showed a significant improvement in the compliance rate of nurses performing pre-chemotherapy assessments for cancer patients. Patient satisfaction and chemotherapy safety were also improved through the project's implementation, and the participating nurses' enthusiasm and belief in implementing evidence into practice was increased. CONCLUSION: The study demonstrated the feasibility of academic centres working with hospitals to promote the dissemination of evidence in clinical practice to accelerate knowledge translation. Further research is needed on the effectiveness of cross-regional and cross-organisational collaborations to facilitate evidence dissemination.

5.
Nat Commun ; 15(1): 3890, 2024 May 08.
Article in English | MEDLINE | ID: mdl-38719850

ABSTRACT

Shigella flexneri is a Gram-negative bacterium causing severe bloody dysentery. Its pathogenesis is largely dictated by a plasmid-encoded type III secretion system (T3SS) and its associated effectors. Among these, the effector OspG has been shown to bind to the ubiquitin conjugation machinery (E2~Ub) to activate its kinase activity. However, the cellular targets of OspG remain elusive despite years of extensive efforts. Here we show by unbiased phosphoproteomics that a major target of OspG is CAND1, a regulatory protein controlling the assembly of cullin-RING ubiquitin ligases (CRLs). CAND1 phosphorylation weakens its interaction with cullins, which is expected to impact a large panel of CRL E3s. Indeed, global ubiquitome profiling reveals marked changes in the ubiquitination landscape when OspG is introduced. Notably, OspG promotes ubiquitination of a class of cytoskeletal proteins called septins, thereby inhibiting formation of cage-like structures encircling cytosolic bacteria. Overall, we demonstrate that pathogens have evolved an elaborate strategy to modulate host ubiquitin signaling to evade septin-cage entrapment.


Subject(s)
Bacterial Proteins , Septins , Shigella flexneri , Signal Transduction , Ubiquitin , Ubiquitination , Shigella flexneri/metabolism , Shigella flexneri/pathogenicity , Septins/metabolism , Septins/genetics , Humans , Ubiquitin/metabolism , Bacterial Proteins/metabolism , Bacterial Proteins/genetics , Phosphorylation , Host-Pathogen Interactions , HeLa Cells , Cullin Proteins/metabolism , Ubiquitin-Protein Ligases/metabolism , Ubiquitin-Protein Ligases/genetics , HEK293 Cells , Dysentery, Bacillary/microbiology , Dysentery, Bacillary/metabolism
6.
Sci Total Environ ; : 173390, 2024 May 28.
Article in English | MEDLINE | ID: mdl-38815831

ABSTRACT

Vehicle exhaust is the primary source of polycyclic aromatic compounds (PACs). Real road tests using a portable vehicle measurement system on light-duty gasoline vehicles and light-duty diesel trucks were conducted to investigate gas- and particle-phase polycyclic aromatic hydrocarbons (PAHs), nitro-PAHs (NPAHs), and oxy-PAHs (OPAHs) in vehicle exhaust with different emission standards, fuel types, and altitudes. The results showed that with the tightening of emission standards, the overall emission factors (EFs) of PACs decreased. Compared with China V diesel vehicles, the emissions of PAHs, OPAHs, and NPAHs from China VI diesel vehicles were 75.1 %, 84.4 %, and 61.2 % lower, respectively. With a ~100 m increase in altitude, the EFs of PAHs, OPAHs, and NPAHs of diesel vehicles increased 1.88, 1.92, and 1.59 times due to incomplete combustion. In addition, the EFs of PAHs and OPAHs in gasoline vehicles were lower than those in diesel vehicles. In contrast, the proportion of PAHs with highly toxic components, such as dibenzo[a,h]anthracene (DahA) and benzo[a]pyrene (BaP), and the EFs of gas-phase NPAHs in gasoline vehicles were higher than those in diesel vehicles. Furthermore, the emissions of 1,8-DNP from diesel vehicles cannot be disregarded. 1,8-DNP was the main gas-phase NPAHs emitted by China VI and China V diesel vehicles, accounting for 49.3 % and 26.0 %, respectively. Moreover, gas-phase PACs contributed more to the EFs than particle-phase PACs, whereas particle-phase PACs have greater toxic effects. Although the EFs of PAHs are more than 100 times those of NPAHs, the toxic equivalent concentrations (TEQBaP) of PAHs in diesel and gasoline vehicles were approximately 6.5 times and 35 times those of NPAHs. The spatial distribution characteristics revealed that PACs emissions were mainly concentrated in urban areas and highways, and the differences in the toxicity of PACs emissions between different cities depended on the proportion of diesel vehicles. The average TEQBaP of PAHs and NPAHs in Haidong, Haibei, Huangnan, Hainan, Guoluo, and Yushu was 8.42 µg/m3 and 0.36 µg/m3, respectively, while those of Xining and Haixi were 0.24-0.29 µg/m3 and 0.09-0.108 µg/m3 higher, respectively. This study provides a comprehensive understanding of the emission characteristics, health risks, and spatial distribution of PACs from diesel and gasoline vehicle PACs in urban areas.

7.
PLoS Pathog ; 20(5): e1011783, 2024 May.
Article in English | MEDLINE | ID: mdl-38739652

ABSTRACT

Legionella pneumophila strains harboring wild-type rpsL such as Lp02rpsLWT cannot replicate in mouse bone marrow-derived macrophages (BMDMs) due to induction of extensive lysosome damage and apoptosis. The bacterial factor directly responsible for inducing such cell death and the host factor involved in initiating the signaling cascade that leads to lysosome damage remain unknown. Similarly, host factors that may alleviate cell death induced by these bacterial strains have not yet been investigated. Using a genome-wide CRISPR/Cas9 screening, we identified Hmg20a and Nol9 as host factors important for restricting strain Lp02rpsLWT in BMDMs. Depletion of Hmg20a protects macrophages from infection-induced lysosomal damage and apoptosis, allowing productive bacterial replication. The restriction imposed by Hmg20a was mediated by repressing the expression of several endo-lysosomal proteins, including the small GTPase Rab7. We found that SUMOylated Rab7 is recruited to the bacterial phagosome via SulF, a Dot/Icm effector that harbors a SUMO-interacting motif (SIM). Moreover, overexpression of Rab7 rescues intracellular growth of strain Lp02rpsLWT in BMDMs. Our results establish that L. pneumophila exploits the lysosomal network for the biogenesis of its phagosome in BMDMs.


Subject(s)
Legionella pneumophila , Lysosomes , Macrophages , Phagosomes , rab GTP-Binding Proteins , rab7 GTP-Binding Proteins , Legionella pneumophila/metabolism , Legionella pneumophila/genetics , Animals , rab GTP-Binding Proteins/metabolism , Mice , Phagosomes/metabolism , Phagosomes/microbiology , Lysosomes/metabolism , Lysosomes/microbiology , Macrophages/microbiology , Macrophages/metabolism , Legionnaires' Disease/metabolism , Legionnaires' Disease/microbiology , Sumoylation , Mice, Inbred C57BL , Endosomes/metabolism , Endosomes/microbiology
8.
J Med Internet Res ; 26: e51496, 2024 May 17.
Article in English | MEDLINE | ID: mdl-38758590

ABSTRACT

BACKGROUND: The internet community has become a significant source for researchers to conduct qualitative studies analyzing users' views, attitudes, and experiences about public health. However, few studies have assessed the ethical issues in qualitative research using social media data. OBJECTIVE: This study aims to review the reportage of ethical considerations in qualitative research utilizing social media data on public health care. METHODS: We performed a scoping review of studies mining text from internet communities and published in peer-reviewed journals from 2010 to May 31, 2023. These studies, limited to the English language, were retrieved to evaluate the rates of reporting ethical approval, informed consent, and privacy issues. We searched 5 databases, that is, PubMed, Web of Science, CINAHL, Cochrane, and Embase. Gray literature was supplemented from Google Scholar and OpenGrey websites. Studies using qualitative methods mining text from the internet community focusing on health care topics were deemed eligible. Data extraction was performed using a standardized data extraction spreadsheet. Findings were reported using PRISMA-ScR (Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews) guidelines. RESULTS: After 4674 titles, abstracts, and full texts were screened, 108 studies on mining text from the internet community were included. Nearly half of the studies were published in the United States, with more studies from 2019 to 2022. Only 59.3% (64/108) of the studies sought ethical approval, 45.3% (49/108) mentioned informed consent, and only 12.9% (14/108) of the studies explicitly obtained informed consent. Approximately 86% (12/14) of the studies that reported informed consent obtained digital informed consent from participants/administrators, while 14% (2/14) did not describe the method used to obtain informed consent. Notably, 70.3% (76/108) of the studies contained users' written content or posts: 68% (52/76) contained verbatim quotes, while 32% (24/76) paraphrased the quotes to prevent traceability. However, 16% (4/24) of the studies that paraphrased the quotes did not report the paraphrasing methods. Moreover, 18.5% (20/108) of the studies used aggregated data analysis to protect users' privacy. Furthermore, the rates of reporting ethical approval were different between different countries (P=.02) and between papers that contained users' written content (both direct and paraphrased quotes) and papers that did not contain users' written content (P<.001). CONCLUSIONS: Our scoping review demonstrates that the reporting of ethical considerations is widely neglected in qualitative research studies using social media data; such studies should be more cautious in citing user quotes to maintain user privacy. Further, our review reveals the need for detailed information on the precautions of obtaining informed consent and paraphrasing to reduce the potential bias. A national consensus of ethical considerations such as ethical approval, informed consent, and privacy issues is needed for qualitative research of health care using social media data of internet communities.


Subject(s)
Qualitative Research , Social Media , Social Media/ethics , Humans , Public Health/ethics , Informed Consent/ethics
9.
Front Pharmacol ; 15: 1372456, 2024.
Article in English | MEDLINE | ID: mdl-38681197

ABSTRACT

The Nicotiana tabacum L. plant, a medicinal resource, holds significant potential for benefiting human health, as evidenced by its use in Native American and ancient Chinese cultures. Modern medical and pharmaceutical studies have investigated that the abundant and distinctive function metabolites in tobacco including nicotine, solanesol, cembranoid diterpenes, essential oil, seed oil and other tobacco extracts, avoiding the toxic components of smoke, mainly have the anti-oxidation, anti-lipid production, pro-lipid oxidation, pro-insulin sensitivity, anti-inflammation, anti-apoptosis and antimicrobial activities. They showed potential pharmaceutical value mainly as supplements or substitutes for treating neurodegenerative diseases including Alzheimer's and Parkinson's disease, inflammatory diseases including colitis, arthritis, sepsis, multiple sclerosis, and myocarditis, and metabolic syndrome including Obesity and fatty liver. This review comprehensively presents the research status and the molecular mechanisms of tobacco and its metabolites basing on almost all the English and Chinese literature in recent 20 years in the field of medicine and pharmacology. This review serves as a foundation for future research on the medicinal potential of tobacco plants.

10.
J Am Heart Assoc ; 13(6): e031867, 2024 Mar 19.
Article in English | MEDLINE | ID: mdl-38497483

ABSTRACT

BACKGROUND: Circular RNAs can serve as regulators influencing the development of pulmonary hypertension (PH). However, their function in pulmonary vascular intimal injury remains undefined. Thus, we aimed to identify specifically expressed circular RNAs in pulmonary microvascular endothelial cells (PMECs) under hypoxia and PH. METHODS AND RESULTS: Deep RNA sequencing and quantitative real-time polymerase chain reaction revealed that circALMS1 (circular RNA Alstrom syndrome protein 1) was reduced in human PMECs under hypoxia (P<0.0001). Molecular biology and histopathology experiments were used to elucidate the roles of circALMS1 in regulating PMEC dysfunction among patients with PH. The circALMS1 expression was decreased in the plasma of patients with PH (P=0.0315). Patients with lower circALMS1 levels had higher risk of death (P=0.0006). Moreover, the circALMS1 overexpression of adeno-associated viruses improved right ventricular function and reduced pulmonary vascular remodeling in monocrotaline-PH and sugen/hypoxia-PH rats (P<0.05). Furthermore, circALMS1 overexpression promoted apoptosis and inhibited PMEC proliferation and migration under hypoxia by directly downregulating miR-17-3p (P<0.05). Dual luciferase assay confirmed the direct binding of circALMS1 to miR-17-3p and miR-17-3p binding to its target gene YT521-B homology domain-containing family protein 2 (YTHDF2) (P<0.05). The YTHDF2 levels were also downregulated in hypoxic PMECs (P<0.01). The small interfering RNA YTHDF2 reversed the effects of miR-17-3p inhibitors on PMEC proliferation, migration, and apoptosis. Finally, the results indicated that, although YTHDF2, as an N(6)-methyladenosine reader protein, contributes to the degradation of many circular RNAs, it could not regulate the circALMS1 levels in PMECs (P=0.9721). CONCLUSIONS: Our study sheds new light on circALMS1-regulated dysfunction of PMECs by the miR-17-3p/YTHDF2 pathway under hypoxia and provides insights into the underlying pathogenesis of PH.


Subject(s)
Hypertension, Pulmonary , MicroRNAs , Humans , Rats , Animals , Hypertension, Pulmonary/metabolism , MicroRNAs/metabolism , Endothelial Cells/metabolism , RNA, Circular/genetics , Pulmonary Artery , Hypoxia/complications , Cell Proliferation/physiology
11.
Front Immunol ; 15: 1374506, 2024.
Article in English | MEDLINE | ID: mdl-38529271

ABSTRACT

Pulmonary hypertension (PH) is a malignant disease with progressive increase of pulmonary vascular pressure, which eventually leads to right heart failure. More and more evidences show that immune cells and inflammation play an important role in the occurrence and development of PH. In the context of pulmonary vascular diseases, immune cells migrate into the walls of the pulmonary vascular system. This leads to an increase in the levels of cytokines and chemokines in both the bloodstream and the surrounding tissues of the pulmonary vessels. As a result, new approaches such as immunotherapy and anti-inflammatory treatments are being considered as potential strategies to halt or potentially reverse the progression of PH. We reviewed the potential mechanisms of immune cells, cytokines and chemokines in PH development. The potential relationship of vascular cells or bone morphogenetic protein receptor 2 (BMPR2) in immune regulation was also expounded. The clinical application and future prospect of immunotherapy were further discussed.


Subject(s)
Hypertension, Pulmonary , Humans , Hypertension, Pulmonary/therapy , Hypertension, Pulmonary/metabolism , Lung/pathology , Inflammation/metabolism , Cytokines/metabolism , Chemokines/metabolism
12.
Brain Behav ; 14(4): e3472, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38549560

ABSTRACT

BACKGROUND: Anticipated HIV stigma among men who have sex with men's (MSM) has a severe negative effect on their physical and mental health wellbeing and hence requires specific attention. The current study aims to identify the characteristics and the psychosocial influencing factors of anticipated HIV stigma in MSM using regression mixture model (RMM) and to determine the cut-off point of the seven-item Anticipated HIV Stigma Questionnaire (AHSQ) using the receiver operating characteristic (ROC) analysis. METHODS: A cross-sectional study was conducted among HIV-negative/unknown MSM from Blued online platform in China from December 16th, 2020 to March 1st, 2021, enrolling 1394 participants. Data were collected on demographic characteristics, perceived social support, anticipated HIV stigma, depressive symptoms, and HIV knowledge. Latent profile analysis was performed to identify different profiles of anticipated HIV stigma level. Chi-square test, analysis of variance, and RMM analysis were conducted to explore the influencing factors in different profiles. ROC analyses were carried out to identify the cut-off value of anticipated stigma. RESULTS: Among the participants, three profiles of anticipated stigma were identified: "low anticipated HIV stigma" (12.0%), "moderate anticipated HIV stigma" (52.1%), and "severe anticipated HIV stigma" (35.9%). RMM analysis showed that higher income and higher levels of knowledge were positively associated with moderate anticipated HIV stigma, whereas full-time job and social support were negatively associated with moderate anticipated HIV stigma; higher income, depressive symptoms, and knowledge were positively associated with severe anticipated HIV stigma, whereas minor ethnicity and social support were negatively associated with severe anticipated HIV stigma. ROC curve of the AHSQ showed that the optimal cut-off value of ≥16 could indicate positive anticipated HIV stigma. CONCLUSION: The study focuses on the level of anticipated HIV stigma and its psycho-socio influencing factors among HIV-negative/unknown MSM. It provides evidence for implementing relevant psychological interventions to HIV-negative/unknown MSM.


Subject(s)
HIV Infections , Sexual and Gender Minorities , Male , Humans , Homosexuality, Male/psychology , HIV , Cross-Sectional Studies , HIV Infections/psychology , China
13.
Heliyon ; 10(6): e26916, 2024 Mar 30.
Article in English | MEDLINE | ID: mdl-38509878

ABSTRACT

The incidence rate of Parkinson's disease (PD) is increasing yearly. Neuronal apoptosis caused by abnormal protein phosphorylation is closely related to the pathogenesis of Parkinson's disease. At present, few PD-specific apoptosis pathways have been revealed. To investigate the effect of Baichanting (BCT) on apoptosis from the perspective of protein phosphorylation, α-syn transgenic mice were selected to observe the behavioral changes of the mice, and the apoptosis of substantia nigra cells were detected by the HE method and TUNEL method. Network pharmacology combined with phosphorylation proteomics was used to find relevant targets for BCT treatment of PD and was further verified by PRM and western blotting. BCT improved the morphology of neurons in the substantia nigra and reduced neuronal apoptosis. The main enriched pathways in the network pharmacology results were apoptosis, the p53 signaling pathway and autophagy. Western blot results showed that BCT significantly regulated the protein expression levels of BAX, Caspase-3, LC3B, P53 and mTOR and upregulated autophagy to alleviate apoptosis. Using phosphorylated proteomics and PRM validation, we found that Pak5, Grin2b, Scn1a, BcaN, L1cam and Braf are closely correlated with the targets of the web-based pharmacological screen and may be involved in p53/mTOR-mediated autophagy and apoptosis pathways. BCT can inhibit the activation of the p53/mTOR signaling pathway, thereby enhancing the autophagy function of cells, and reducing the apoptosis of neurons which is the main mechanism of its neuroprotective effect.

14.
Heliyon ; 10(6): e27597, 2024 Mar 30.
Article in English | MEDLINE | ID: mdl-38500998

ABSTRACT

Background: /aims: Atherosclerosis (AS) is the common pathological basis of a variety of cardiovascular diseases (CVD), and has become the main cause of human death worldwide, and the incidence is increasing and younger trend. Ginsenoside Rb1 (Rb1), an important monomer component of the traditional Chinese herb ginseng, known for its ability to improve blood lipid disorders and anti-inflammatory. In addition, Rb1 was proved to be an effective treatment for AS. However, the effect of Rb1 on AS remains to be elucidated. The aim of this study was to investigate the mechanisms of Rb1 in ameliorating AS induced by high-fat diet (HFD). Materials and methods: In this study, we developed an experimental AS model in Sprague-Dawley rats by feeding HFD with intraperitoneal injection of vitamin D3. The potential therapeutic mechanism of Rb1 in AS rats was investigated by detecting the expression of inflammatory factors, microbiome 16S rRNA gene sequencing, short-chain fatty acids (SCFAs) targeted metabolomics and untargeted metabolomics. Results: Rb1 could effectively alleviate the symptoms of AS and suppress the overexpression of inflammation-related factors. Meanwhile, Rb1 altered gut microbial composition and concentration of SCFAs characterized by Bacteroidetes, Actinobacteria, Lactobacillus, Prevotella, Oscillospira enrichment and Desulfovibrio depletion, accompanied by increased production of acetic acid and propionic acid. Moreover, untargeted metabolomics showed that Rb1 considerably improved faecal metabolite profiles, particularly arachidonic acid metabolism and primary bile acid biosynthesis. Conclusion: Rb1 ameliorated the HFD-induced AS, and the mechanism is related to improving intestinal metabolic homeostasis and inhibiting systemic inflammation by regulating gut microbiota.

15.
Nat Commun ; 15(1): 2452, 2024 Mar 19.
Article in English | MEDLINE | ID: mdl-38503748

ABSTRACT

ADP-ribosylation is a reversible post-translational modification involved in various cellular activities. Removal of ADP-ribosylation requires (ADP-ribosyl)hydrolases, with macrodomain enzymes being a major family in this category. The pathogen Legionella pneumophila mediates atypical ubiquitination of host targets using the SidE effector family in a process that involves ubiquitin ADP-ribosylation on arginine 42 as an obligatory step. Here, we show that the Legionella macrodomain effector MavL regulates this pathway by reversing the arginine ADP-ribosylation, likely to minimize potential detrimental effects caused by the modified ubiquitin. We determine the crystal structure of ADP-ribose-bound MavL, providing structural insights into recognition of the ADP-ribosyl group and catalytic mechanism of its removal. Further analyses reveal DUF4804 as a class of MavL-like macrodomain enzymes whose representative members show unique selectivity for mono-ADP-ribosylated arginine residue in synthetic substrates. We find such enzymes are also present in eukaryotes, as exemplified by two previously uncharacterized (ADP-ribosyl)hydrolases in Drosophila melanogaster. Crystal structures of several proteins in this class provide insights into arginine specificity and a shared mode of ADP-ribose interaction distinct from previously characterized macrodomains. Collectively, our study reveals a new regulatory layer of SidE-catalyzed ubiquitination and expands the current understanding of macrodomain enzymes.


Subject(s)
Legionella , Ubiquitin , Animals , Ubiquitin/metabolism , Legionella/metabolism , Drosophila melanogaster/metabolism , ADP-Ribosylation , Adenosine Diphosphate Ribose/metabolism , Hydrolases/metabolism
16.
Animal Model Exp Med ; 7(1): 24-35, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38369683

ABSTRACT

BACKGROUND: Our previous study found that mouse embryonic neural stem cell (NSC)-derived exosomes (EXOs) regulated NSC differentiation via the miR-9/Hes1 axis. However, the effects of EXOs on brain microvascular endothelial cell (BMEC) dysfunction via the miR-9/Hes1 axis remain unknown. Therefore, the current study aimed to determine the effects of EXOs on BMEC proliferation, migration, and death via the miR-9/Hes1 axis. METHODS: Immunofluorescence, quantitative real-time polymerase chain reaction, cell counting kit-8 assay, wound healing assay, calcein-acetoxymethyl/propidium iodide staining, and hematoxylin and eosin staining were used to determine the role and mechanism of EXOs on BMECs. RESULTS: EXOs promoted BMEC proliferation and migration and reduced cell death under hypoxic conditions. The overexpression of miR-9 promoted BMEC proliferation and migration and reduced cell death under hypoxic conditions. Moreover, miR-9 downregulation inhibited BMEC proliferation and migration and also promoted cell death. Hes1 silencing ameliorated the effect of amtagomiR-9 on BMEC proliferation and migration and cell death. Hyperemic structures were observed in the regions of the hippocampus and cortex in hypoxia-induced mice. Meanwhile, EXO treatment improved cerebrovascular alterations. CONCLUSION: NSC-derived EXOs can promote BMEC proliferation and migration and reduce cell death via the miR-9/Hes1 axis under hypoxic conditions. Therefore, EXO therapeutic strategies could be considered for hypoxia-induced vascular injury.


Subject(s)
Exosomes , MicroRNAs , Neural Stem Cells , Animals , Mice , Endothelial Cells/metabolism , Exosomes/metabolism , MicroRNAs/genetics , Hypoxia/metabolism , Cell Proliferation/genetics , Cell Death , Brain/metabolism , Neural Stem Cells/metabolism , Transcription Factor HES-1/metabolism
17.
Clin Cardiol ; 47(2): e24245, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38402556

ABSTRACT

BACKGROUND: While the GRIPHON study and others have confirmed the efficacy and safety of selexipag with single, dual, and initial triple combination therapy for patients with pulmonary arterial hypertension (PAH), multicenters studies concerning diverse triple oral combination therapies based on selexipag are limited. HYPOTHESIS: This study was conducted to evaluate the effects of various sequential triple oral combination therapies on PAH outcomes. METHODS: A retrospective study was carried out involving 192 patients from 10 centers, who were receiving sequential triple oral combination therapy consisting of an endothelin receptor antagonist (ERA), a phosphodiesterase 5 inhibitor (PDE5i)/riociguat and selexipag. Clinical parameters, event-free survival, and all-cause survival were assessed and analyzed at baseline and posttreatment. RESULTS: Among the 192 patients, 37 were treated with ERA + riociguat + selexipag, and 155 patients received ERA + PDE5i + selexipag. Both sequential triple oral combination therapies improved the World Health Organization functional class and raised the count of low-risk parameters. As a result of the larger patients' population in the ERA + PDE5i + selexipag group, these individuals exhibited significant increases in 6-minute walking distance (6MWD), pulmonary arterial systolic pressure, pulmonary arterial pressure, right ventricle, and eccentricity index, and significant decreases in N-terminal probrain natriuretic peptide after 6 months of treatment. Nevertheless, both sequential triple oral combination therapy groups demonstrated similar shifts in these clinical parameters between baseline and 6 months. Baseline 6MWD and mean pulmonary arterial pressure were independent predictors of survival in patients undergoing ERA + PDE5i + selexipag therapy. Importantly, no significant differences were found in 6-month event-free survival and all-cause survival between two groups. CONCLUSIONS: Different oral sequential triple combination therapies based on selexipag could comparably improve outcomes in patients with PAH.


Subject(s)
Pulmonary Arterial Hypertension , Humans , Pulmonary Arterial Hypertension/diagnosis , Pulmonary Arterial Hypertension/drug therapy , Retrospective Studies , Acetamides , Pyrazines/adverse effects
18.
Analyst ; 149(6): 1921-1928, 2024 Mar 11.
Article in English | MEDLINE | ID: mdl-38375539

ABSTRACT

The electrochemical detection method of cytotoxicity using intracellular purines as biomarkers has shown great potential for in vitro drug toxicity evaluation. However, no electrochemical detection system based on an in vitro drug metabolism mechanism has been devised. In this paper, electrochemical voltammetry was used to investigate the effect of the S9 system on the electrochemical behavior of HepG2 cells, and benzo[a]pyrene, fluoranthene, and pyrene were employed to investigate the sensitivity of electrochemical signals of cells to the cytotoxicity of drugs metabolized by the S9 system. The results showed that, within 8 h of exposure to the S9 system, the electrochemical signal of HepG2 cells at 0.7 V did not alter noticeably. The levels of xanthine, guanine, hypoxanthine, and adenine in the cells were not significantly altered. Compared with the absence of S9 system metabolism, benzo[a]pyrene and fluoranthene processed by the S9 system decreased the electrochemical signal of the cells in a dose-dependent manner, while pyrene did not change it appreciably. HPLC also revealed that benzo[a]pyrene and fluoranthene metabolized by the S9 system decreased the intracellular purine levels, whereas pyrene had no effect on them before and after S9 system metabolism. The cytotoxicity results of the three drugs examined by electrochemical voltammetry and MTT assay showed a strong correlation and good agreement. The S9 system had no effect on the intracellular purine levels or the electrochemical signal of cells. When the drug was metabolized by the S9 system, variations in cytotoxicity could be precisely detected by electrochemical voltammetry.


Subject(s)
Benzo(a)pyrene , Biochemical Phenomena , Benzo(a)pyrene/metabolism , Benzo(a)pyrene/toxicity , Fluorenes/toxicity , Guanine , Mutagens
19.
Aging (Albany NY) ; 16(3): 2657-2678, 2024 Feb 05.
Article in English | MEDLINE | ID: mdl-38319724

ABSTRACT

BACKGROUND: Multiple myeloma (MM) is an incurable B-cell malignancy, but with the emergence of immunotherapy, a potential cure is hopeful. The individualized interaction between the tumor and bone marrow (BM) microenvironment determines the response to immunotherapy. Angiogenesis is a constant hallmark of the BM microenvironment in MM. However, little is known about the potency ability of angiogenesis-associated genes (AAGs) to regulate the immune microenvironment of MM patients. METHODS: We comprehensively dissected the associations between angiogenesis and genomic landscapes, prognosis, and the immune microenvironment by integrating 36 AAGs. Immunohistochemistry was performed to verify the correlation between angiogenic factor expression and patient prognosis. Single-sample gene set enrichment analysis was applied to quantify the relative abundance of 28 infiltrating cells. The AAG score was constructed using the least absolute shrinkage and selection operator Cox regression model. RESULTS: Angiogenesis was closely correlated with MM patient prognosis, and the mutation intensity of the AAGs was low. Immunohistochemistry confirmed that high microvessel density predicted poor prognosis. Three AAG clusters and two gene clusters with distinct clinical outcomes and immune characteristics were identified. The established AAG_score model performed well in predicting patient prognosis and active immunotherapy response. The high-AAG_score subgroup was characterized by reduced immune cell infiltration, poor prognosis, and inactive immunotherapy response. Multivariate analyses indicated that the AAG_score was strongly robust and independent among the prognostic variables. CONCLUSION: This study revealed that angiogenesis is significantly related to MM patient prognosis and immune phenotype. Evaluating the AAG signature was conducive to predicting patient response to immunotherapy and guiding more efficacious immunotherapy strategies.


Subject(s)
Multiple Myeloma , Humans , Multiple Myeloma/genetics , Multiple Myeloma/therapy , Angiogenesis , Cardiovascular Physiological Phenomena , Genomics , Immunotherapy , Tumor Microenvironment/genetics , Prognosis
20.
Opt Express ; 32(1): 275-286, 2024 Jan 01.
Article in English | MEDLINE | ID: mdl-38175055

ABSTRACT

A kind of temperature and magnetic field sensor using Fabry-Perot interferometers (FPIs) and Vernier effect to enhance sensitivity is proposed. The sensor structure involves filling the FP air cavities with polydimethylsiloxane (PDMS) and magnetic fluid (MF) to create the PDMS and MF cavities for temperature and magnetic field detection, respectively. The two cavities are reflective structures, which are interconnected in series through a fiber-optic circulator. Experimental data demonstrates that the Vernier effect effectively enhances the sensor sensitivity. The average temperature sensitivity of the sensor is 26765 pm/°C within the range of 35∼39.5°C. The magnetic field intensity sensitivity is obtained to be -2245 pm/mT within the range of 3∼11 mT. The sensitivities of the temperature and magnetic field using the Vernier effect are about five times larger than those of the corresponding single FP cavity counterparts.

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