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1.
PNAS Nexus ; 3(9): pgae334, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39262855

RESUMEN

Dysregulation of cholesterol metabolism underlies neurodegenerative disease and is increasingly implicated in neuroinflammatory diseases, such as multiple sclerosis (MS). Cytochrome P450 family 7 subfamily B member 1 (CYP7B1) is a key enzyme in alternative cholesterol metabolism. A recessive mutation in the gene CYP7B1 is known to cause a neurodegenerative disease, hereditary spastic paraplegia type 5 and oxysterol accumulation. However, the role of CYP7B1 in neuroinflammation has been little revealed. In this study, we induced experimental autoimmune encephalomyelitis (EAE), as a murine model of MS, using CYP7B1 homozygous knockout (KO) mice. We found that CYP7B1 deficiency can significantly attenuate EAE severity. CYP7B1 deficiency is sufficient to reduce leukocyte infiltration into the central nervous system, suppress proliferation of pathogenic CD4+ T cells, and decrease myeloid cell activation during EAE. Additionally, live-animal imaging targeting translocator protein expression, an outer mitochondrial membrane protein biomarker of neuroinflammation, showed that CYP7B1 deficiency results in suppressed neuroinflammation. Using human monocyte-derived microglia-like cellular disease model and primary microglia of CYP7B1 KO mice, we also found that activation of microglia of CYP7B1 deficiency was impaired. These cumulative results suggest that CYP7B1 can regulate neuroinflammation, thus providing potential new targets for therapeutic intervention.

2.
Artículo en Inglés | MEDLINE | ID: mdl-39186315

RESUMEN

OBJECTIVE: Human T-cell leukemia virus type 1-associated myelopathy (HAM) is a chronic, progressive, inflammatory disease with unclear pathogenesis and no effective treatments. We aimed to investigate a novel mechanistic theory and treat HAM patients with rituximab, which can deplete CD20+ B lymphocytes in circulation. METHODS: Single-cell RNA sequencing (scRNA-seq) data was analyzed to identify HTLV-1-associated B cells and their effect on T cells. An observational analysis of our HAM cohort was conducted to elucidate changes in the immunological microenvironment of these patients. Peripheral blood mononuclear cells (PBMC) from HAM patients were isolated to explore the efficacy of B cell depletion in vitro. To assess the effect of B-cell depletion on HAM patients, eligible participants in our cohort received rituximab therapy (NCT04004819). RESULTS: ScRNA-seq results suggest a significant effect of HTLV-1-associated B cells on T cells. Additionally, HTLV-1 was found to infect B cells and depletion of B cells inhibited the proliferation of T cells. Number of B cells in HAM patients had positive correlation with the proviral load and infected cell counts. Depletion of B cells led to a reduction in HTLV-1 proviral load in vitro. Furthermore, in clinical trial, 14 HAM patients were enrolled. Three patients (21.4%) who received rituximab failed to achieve remission, compared to 24 (85.7%) patients received any other therapy that failed to achieve remission. With a low level of circulating B cells, the proportion of Ki67-positive cells in CD4+ T cells fell. INTERPRETATION: This study provided evidence that depleting B-lymphocytes is an innovative strategy for treating patients with HAM and broadens the understanding of the role of B cells in infectious immunity.

4.
Biomed Pharmacother ; 178: 117188, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39053427

RESUMEN

Multiple sclerosis (MS) is an autoimmune-mediated chronic inflammatory demyelinating disease of the central nervous system (CNS) that poses significant treatment challenges. Currently, it is believed that inflammatory and neuroprotective reactive astrocytes, along with other resident CNS cells and immune cells, contribute to the pathophysiology of MS. In our study, we found that isoliquiritigenin (ILG), a bioactive chalcone compound, significantly reduces the clinical scores of experimental autoimmune encephalomyelitis (EAE) by 44 % (P < 0.05). Additionally, ILG significantly decreases the pathological scores of spinal cord inflammation and demyelination by 61 % and 65 %, respectively (both P < 0.0001). Furthermore, ILG affects the populations of CD4, Th1, Th17, and Treg cells in vivo. More importantly, ILG significantly promotes the activation of astrocytes in EAE (P < 0.0001). Additionally, ILG treatment indirectly inhibits inflammatory reactive astrocytes and promotes neuroprotective reactive astrocytes. It reduces spleen levels of TNFα, IL1α, C1qa, IL1ß, and IL17A by 95 % (P < 0.001), 98 % (P < 0.01), 46 % (P < 0.05), 97 % (P < 0.001), and 60 % (P < 0.001), respectively. It also decreases CNS levels of TNFα, IL1α, C1qa, IL1ß, and IL17A by 53 % (P < 0.05), 88 % (P < 0.05), 64 % (P < 0.01), 57 % (P < 0.05), and 60 % (P < 0.001), respectively. These results indicate that ILG exerts an immunoregulatory effect by inhibiting the secretion of pro-inflammatory cytokines. Consequently, ILG inhibits inflammatory reactive astrocytes, promotes neuroprotective reactive astrocytes, alleviates inflammation and improves EAE. These findings provide a theoretical basis and support for the application of ILG in the prevention and treatment of MS.


Asunto(s)
Astrocitos , Chalconas , Encefalomielitis Autoinmune Experimental , Ratones Endogámicos C57BL , Fármacos Neuroprotectores , Encefalomielitis Autoinmune Experimental/tratamiento farmacológico , Encefalomielitis Autoinmune Experimental/patología , Animales , Astrocitos/efectos de los fármacos , Astrocitos/metabolismo , Astrocitos/patología , Chalconas/farmacología , Chalconas/uso terapéutico , Femenino , Ratones , Fármacos Neuroprotectores/farmacología , Citocinas/metabolismo , Esclerosis Múltiple/tratamiento farmacológico , Esclerosis Múltiple/patología , Médula Espinal/efectos de los fármacos , Médula Espinal/patología , Médula Espinal/metabolismo , Antiinflamatorios/farmacología
5.
Front Pharmacol ; 15: 1345897, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38689665

RESUMEN

Objectives: The purpose of the study was to comprehensively evaluate efficacy and safety of CDDP in patients with AMI undergoing PCI. Methods: A computerised search was conducted on the CNKI, WF, VIP, CBM, PubMed, Embase, Web of Science, and Cochrane Library databases for RCTs of CDDP adjuvant therapy for AMI up to May 2023. STATA 17.0 was used to perform meta-analyses, sensitivity analyses, subgroup analyses, meta-regression, and publication bias assessments. TSA 0.9.5.10 Beta was used for trial sequential analysis (TSA). Evidence confidence of meta results was evaluated by GRADE (Grading of Recommendations Assessment, Development and Evaluation) according to the instructions. Results: The results of the meta-analysis showed that CDDP combined with conventional western treatment (CWT) was superior to CWT in increasing LVEF and TCER and decreasing LVEDD, hs-CRP, IL-6 and TNF-α. The quality of evidence for TCER was moderate, LVEF, LVEDD, IL-6, and TNF-α were low. The TSA results showed that the total number of samples collected in this study met the requirements for meta-analysis and excluded the possibility of false positives, further confirming the efficacy of CDDP for the treatment of AMI undergoing PCI. Conclusion: Adjuvant treatment of AMI with CDDP has shown exciting and safe benefits in improving cardiac function and reducing inflammatory response in patients with AMI undergoing PCI, but the quality of some of the included studies was poor, and the results should be interpreted with caution until further confirmation by well-designed RCTs. Systematic Review Registration: [https://www.crd.york.ac.uk/PROSPERO/#recordDetails], identifier [CRD42023453293].

6.
Brain Pathol ; : e13261, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38602336

RESUMEN

Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease, pathologically characterized by TDP-43 aggregates. Recent evidence has been indicated that phosphorylated TDP-43 (pTDP-43) is present not only in motor neurons but also in muscle tissues. However, it is unclear whether testing pTDP-43 aggregation in muscle tissue would assist in the diagnosis of ALS. We propose three key questions: (i) Is aggregation of pTDP-43 detectable in routine biopsied muscles? (ii) Can detection of pTDP-43 aggregation discriminate between ALS and non-ALS patients? (iii) Can pTDP-43 aggregation be observed in the early stages of ALS? We conducted a diagnostic study comprising 2 groups: an ALS group in which 18 cases underwent muscle biopsy screened from a registered ALS cohort consisting of 802 patients and a non-ALS control group, in which we randomly selected 54 muscle samples from a biospecimen bank of 684 patients. Among the 18 ALS patients, 3 patients carried pathological GGGGCC repeats in the C9ORF72 gene, 2 patients carried SOD1 mutations, and 7 patients were at an early stage with only one body region clinically affected. The pTDP-43 accumulation could be detected in routine biopsied muscles, including biceps brachii, deltoid, tibialis anterior, and quadriceps. Abnormal aggregation of pTDP-43 was present in 94.4% of ALS patients (17/18) compared to 29.6% of non-ALS controls (16/54; p < 0.001). The pTDP-43 aggregates were mainly close to the sarcolemma. Using a semi-quantified pTDP-43 aggregates score, we applied a cut-off value of 3 as a diagnostic biomarker, resulting in a sensitivity of 94.4% and a specificity of 83.3%. Moreover, we observed that accumulation of pTDP-43 occurred in muscle tissues prior to clinical symptoms and electromyographic lesions. Our study provides proof-of-concept for the detection of pTDP-43 accumulation via routine muscle biopsy which may serve as a novel biomarker for diagnosis of ALS.

7.
Org Biomol Chem ; 22(6): 1157-1161, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38224149

RESUMEN

Herein, a photoinduced direct C(sp2)-H alkylation of N-heteroaromatics by using commercially available tetrabutylammonium tribromide (TBATB) as a HAT reagent is described. The method uses O2 as the oxidant, and features metal-free, mild reaction conditions and good functional group compatibility.

8.
Heliyon ; 10(1): e23411, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38187318

RESUMEN

Objective: In this paper, we present a comprehensive overview of our experience in establishing and leading distinct extracorporeal cardiopulmonary resuscitation (ECPR)-related teams to independently handle ECPR in the early stages in the emergency department. Methods: A retrospective analysis was conducted on the clinical data of 29 patients who underwent ECPR treatment in the emergency room between May 2018 and April 2022. A control group, consisting of 10 patients treated between May 2018 and September 2019 was managed using a standard rescue coordination mode. The 19 patients who received ECPR between October 2019 and April 2022 were treated by members of the department's 24-h extracorporeal life support team. We compared the implementation and operational challenges faced by the two groups, including item preparation, circuit setup, and ECPR initiation times, among other factors. Results: Gender, age, cardiac arrest risk factors, and other baseline data did not significantly differ between the two groups. Extracorporeal membrane oxygenation (ECMO) pipeline prefilling time (from 35.27±10.34 to 13.46±5.32), ECPR establishment time (from 62.35±29.61 to 30.98±13.41), and item preparation time (from 16.42±9.78 to 3.19±1.49) all considerably decreased when compared to the control group. The rate of return of spontaneous circulation recovery rose from 37.50 % to 77.78 % (P < 0.05). The consequences of gastrointestinal and pulmonary bleeding were greatly reduced while ECPR was being used, and the difference was statistically significant (P < 0.05). Significant improvements were made in the ECPR weaning rate (from 25.00 % to 38.89 %) and survival rate (from 20.0 % to 36.8 %). Conclusion: The establishment of a 24-h extracorporeal life support team significantly reduced the time needed for rescue during the early stage of independent setup of ECPR in the emergency department and serves as a guide for effective care of critically ill patients.

9.
J Org Chem ; 88(16): 12013-12023, 2023 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-37549379

RESUMEN

Difluoromethylated heterocyclic compounds have found broad applications in numerous bioactive molecules. Herein, we report photoredox catalysis-induced direct C-H difluoromethylation of heterocycles by using bis(difluoromethyl) pentacoordinate phosphorane (PPh3(CF2H)2, 1) as the reagent. A variety of heterocycles, such as quinoxalin-2(1H)-one, thiophene, indole, and coumarin, are readily tailored with a difluoromethyl group. The method is featured as transition-metal-free by using an organic compound Erythrosin B as the catalyst and O2 as the oxidant.

10.
J Ethnopharmacol ; 313: 116542, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37127142

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Given the adverse effects of the current principal treatments, there is still a great need for effective cures for rheumatoid arthritis (RA), an immune-mediated disease. Toddalia asiatica (L.) Lam is a traditional medicinal herb that can be used for RA treatment because of its anti-inflammatory and analgesic properties. AIM OF THE STUDY: To investigate the possible effects of Toddalia asiatica extract (TAE) on intestinal immunity and the intestinal bacterial flora in a rat model of RA. MATERIALS AND METHODS: The anti-arthritis effect of TAE was evaluated in arthritis rats induced by complete Freund's adjuvant-induced arthritis (AIA). Arthritis index (AI) scores, systemic inflammation scores, histopathologic changes in the colon and ankle were detected by hematoxylin and eosin staining. Western blot analysis was performed to assess the protein expression of IL-17A, RORC, IL-1ß, IL-6, FOXP3, IL-10 in the colon. RT-PCR was performed to assess the expression of the colon's mRNA. Finally, changes to the gut microbiome by sequencing 16S rDNA. Microbial function prediction was performed using PICRUSt with the KEGG databases and correlation analysis was carried out by computing Spearman's rank correlations. RESULTS: demonstrated that TAE administration at a dose of 3 g/kg dramatically decreased AI scores, systemic inflammation scores, and histopathologic lesions of the ankle and colon in AIA rats. TAE was found to significantly reduce the expression levels of Th17-related proteins and mRNAs (IL-17A, RORC, IL-1ß and IL-6) in the colon, while increasing the expression levels of Treg-related proteins and mRNA (IL-10 and FOXP3), which helped restore the balance of Th17/Treg immune cells in the colon. Meanwhile, TAE was also found to be capable of remodeling the gut microbiota in AIA rats. Depleting RA-associated genera and thereby increasing α-diversity enriched the gut microbiota's diversity and shifted the community composition dramatically, leading to the increase of Firmicutes_unclassified, Ruminococcaceae_unclassified, Muribaculum, Subdoligranulum, Lachnospira, Marvinbryantia, and the reduction of RA-related bacteria Ligilactobacillus, Streptococcus and Eubacterium-eligens-group. Furthermore, PICRUSt analysis revealed that metabolic pathways were associated with TAE treatment, with metabolic pathways dominating. Among them, metabolic pathways were predominant. Correlation studies showed that a total of 9 microorganisms, including Ligilactobacillus, Eubacterium-eligens-group and Subdoligranulum, were significantly associated with Th17/Treg expression. CONCLUSIONS: This study demonstrates that TAE is a low-toxicity poly alkaline drug that can rapidly and effectively improve joint symptoms in RA rats and increases beneficial intestinal bacteria and decreases harmful ones, which is associated with modulating Th17/Treg interactions in intestinal T cells and reversing microbial disorders.


Asunto(s)
Artritis Experimental , Artritis Reumatoide , Medicamentos Herbarios Chinos , Ratas , Animales , Interleucina-10/metabolismo , Interleucina-17/metabolismo , Linfocitos T Reguladores , Interleucina-6/metabolismo , Citocinas/metabolismo , Artritis Experimental/inducido químicamente , Artritis Experimental/tratamiento farmacológico , Inflamación/metabolismo , Artritis Reumatoide/tratamiento farmacológico , Colon/patología , Medicamentos Herbarios Chinos/farmacología , Bacterias/metabolismo , Factores de Transcripción Forkhead/metabolismo , Células Th17
11.
Rev Sci Instrum ; 94(5)2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-37232939

RESUMEN

Fast and accurate frequency estimation is significant for instrumentation and measurement. A sinusoid frequency estimator using discrete Fourier transform (DFT) is presented. DFT is implemented on the sinusoid and the maximum DFT bin is sought out to obtain the coarse estimate. Different from all the existing methods, two asymmetric discrete-time Fourier transform (DTFT) samples situated at arbitrary positions on the same side of the maximum DFT bin are employed to get the fine estimate. The theoretical mean square error is analyzed. To evaluate the estimation performance, the presented estimator is compared with the Cramer-Rao lower bound (CRLB) and state-of-art estimators through computer simulations. Simulation results demonstrate that the presented algorithm is closer to the CRLB compared with the competing methods when the signal-to-noise ratio (SNR) varies in a large range and is unbiased at high SNR.

12.
J Proteome Res ; 22(4): 1193-1200, 2023 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-36856436

RESUMEN

Recently, the prevalence of Aeromonas hydrophila antibiotic-resistant strains has been reported in aquaculture, but its intrinsic antibiotic resistance mechanisms are largely unknown. In the present study, a label-free proteomics technology was used to compare the differential protein abundances in response to norfloxacin (NOR) stress in A. hydrophila. The results showed that there were 186 proteins decreasing and 220 proteins increasing abundances in response to NOR stress. Bioinformatics analysis showed that the differentially expressed proteins were enriched in several biological processes, such as sulfur metabolism and homologous recombination. Furthermore, the antibiotic sensitivity assays showed that the deletion of AHA_0904, cirA, and cysI significantly decreased the resistance against NOR, whereas ΔAHA_1239, ΔcysA, ΔcysD, and ΔcysN significantly increased the resistance against NOR. Our results provide insights into NOR resistance mechanisms and indicate that AHA_0904, cirA, AHA_1239, and sulfur metabolism may play important roles in NOR resistance in A. hydrophila.


Asunto(s)
Aeromonas hydrophila , Norfloxacino , Norfloxacino/farmacología , Norfloxacino/metabolismo , Aeromonas hydrophila/genética , Aeromonas hydrophila/metabolismo , Proteínas Bacterianas/metabolismo , Proteómica/métodos , Antibacterianos/farmacología , Farmacorresistencia Microbiana/genética , Azufre/metabolismo
13.
Environ Microbiol ; 25(5): 977-989, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36604972

RESUMEN

The colicin I receptor (CirA) is a well-studied outer membrane protein that has been reported to play important roles in antibiotic resistance, virulence, and iron homeostasis, although its exact physiological roles require further investigation. In this study, differentially expressed proteins between the ΔahcirA and wild-type (WT) strains of Aeromonas hydrophila were compared using quantitative proteomics. Bioinformatics analysis revealed that the expression of peptide, histidine, and arginine ATP-binding cassette (ABC) transporter system-related proteins was significantly higher in the ΔahcirA strain. Subsequent growth assays revealed that ΔahcirA grew slower than the WT strain in nutrient-limited medium when supplemented with dipeptide, histidine, and arginine as the carbon source. Far-western blot analysis further confirmed that AhCirA can directly bind to histidine/arginine and dipeptide small-molecule substrates in addition to their periplasmic-binding proteins, AhDppA and AhHisJ, respectively. These results indicate that AhCirA may play an important role in the uptake of amino acids and peptides as a channel-forming porin while also directly interacting with ABC transporters to transport nutrient substances into the plasma membrane. Overall, this study demonstrates that AhCirA is a multifunctional protein in A. hydrophila and extends our understanding of known nutrient transport mechanisms among bacteria.


Asunto(s)
Proteínas Bacterianas , Colicinas , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Colicinas/metabolismo , Aeromonas hydrophila/genética , Aeromonas hydrophila/metabolismo , Proteómica/métodos , Histidina/metabolismo , Nutrientes , Arginina/metabolismo
15.
Medicine (Baltimore) ; 101(48): e31900, 2022 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-36482642

RESUMEN

To identify independent factors for predicting loneliness in patients with hematological malignancies. It is an observational cross-sectional study. 157 patients with hematologic malignancies were enrolled between March 2020 and May 2020. The sociodemographic characteristics and psychometric properties (coping styles, self-esteem, big 5 personality traits, and hope) were tested for correlation with loneliness. Multivariate hierarchical regression analysis was then utilized to identify independent risk factors for loneliness. The patients exhibited a mean global score of 36.25 that corresponded to a moderate degree of loneliness. The sociodemographic factors, including occupation, family earning, living areas, times of hospitalization, were significantly related to loneliness. In addition, the coping styles, levels of self-esteem, the big 5 personality traits, and levels of hope were significantly correlated with the degrees of loneliness. Furthermore, sociodemographic factors (occupation) and psychometric properties (coping styles and hope) were identified as independent predictors for loneliness in patients with hematological malignancies. Loneliness is highly prevalent in patients with hematological malignancies. Notably, occupation, times of hospitalization, family earning, coping styles, self-esteem, big 5 personality traits, and hope are all independent risk factors for loneliness.


Asunto(s)
Neoplasias Hematológicas , Soledad , Humanos , Estudios Transversales , Factores de Riesgo , Neoplasias Hematológicas/epidemiología
16.
Ann Transl Med ; 10(12): 676, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35845515

RESUMEN

Background: Accurate and prompt clinical assessment of the severity and prognosis of patients with acute pancreatitis (AP) is critical, particularly during hospitalization. Natural language processing algorithms gain an opportunity from the growing number of free-text notes in electronic health records to mine this unstructured data, e.g., nursing notes, to detect and predict adverse outcomes. However, the predictive value of nursing notes for AP prognosis is unclear. In this study, a predictive model for in-hospital mortality in AP was developed using measured sentiment scores in nursing notes. Methods: The data of AP patients in the retrospective cohort study were collected from the Medical Information Mart for Intensive Care III (MIMIC-III) database. Sentiments in nursing notes were assessed by sentiment analysis. For each individual clinical note, sentiment polarity and sentiment subjectivity scores were assigned. The in-hospital mortality of AP patients was the outcome. A predictive model was built based on clinical information and sentiment scores, and its performance and clinical value were evaluated using the area under curves (AUCs) and decision-making curves, respectively. Results: Of the 631 AP patients included, 88 cases (13.9%) cases were dead in hospital. When various confounding factors were adjusted, the mean sentiment polarity was associated with a reduced risk of in-hospital mortality in AP [odds ratio (OR): 0.448; 95% confidence interval (CI): 0.233-0.833; P=0.014]. A predictive model was established in the training group via multivariate logistic regression analysis, including 12 independent variables. In the testing group, the model showed an AUC of 0.812, which was significantly greater than the sequential organ failure assessment (SOFA) of 0.732 and the simplified acute physiology score-II (SAPS-II) of 0.792 (P<0.05). When the same level of risk was considered, the clinical benefits of the predictive model were found to be the highest compared with SOFA and SAPS-II scores. Conclusions: The model combined sentiment scores in nursing notes showed well predictive performance and clinical value in in-hospital mortality of AP patients.

17.
Antibiotics (Basel) ; 11(7)2022 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-35884095

RESUMEN

The antibiotic resistance of Edwardsiella tarda is becoming increasingly prevalent, and thus novel antimicrobial strategies are being sought. Lysine acylation has been demonstrated to play an important role in bacterial physiological functions, while its role in bacterial antibiotic resistance remains largely unclear. In this study, we investigated the lysine acetylation and succinylation profiles of E. tarda strain EIB202 using affinity antibody purification combined with LC-MS/MS. A total of 1511 lysine-acetylation sites were identified on 589 proteins, and 2346 lysine-succinylation sites were further identified on 692 proteins of this pathogen. Further bioinformatic analysis showed that both post-translational modifications (PTMs) were enriched in the tricarboxylic acid (TCA) cycle, pyruvate metabolism, biosynthesis, and carbon metabolism. In addition, 948 peptides of 437 proteins had overlapping associations with multiple metabolic pathways. Moreover, both acetylation and succinylation were found in many antimicrobial resistance (AMR) proteins, suggesting their potentially vital roles in antibiotic resistance. In general, our work provides insights into the acetylome and succinylome features responsible for the antibiotic resistance mechanism of E. tarda, and the results may facilitate future investigations into the pathogenesis of this bacterium.

18.
J Proteome Res ; 21(7): 1707-1717, 2022 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-35674493

RESUMEN

In recent years, the intracellular mechanisms that contribute to antibiotic resistance have received increasing attention, and outer membrane vesicles (OMVs) have been reported to be related to antibiotic resistance in several Gram-negative bacterial species. However, the intrinsic molecular mechanisms and the form of such antibiotic resistance are still largely unknown. In this study, OMVs from an oxytetracycline (OXY) sensitive aquatic pathogen, Aeromonas hydrophila (OXY-S), were found with significantly increased OXY resistance. Interestingly, the OXY-resistant strain (OXY-R) had a more protective role in OXY resistance. Therefore, a DIA-based quantitative proteomics analysis was performed to compare the differential expression of OMV proteins between OXY-R (OMVsR) and OXY-S (OMVsS). The results showed that seven proteins increased and five proteins decreased in OMVsR vs OMVsS. A subsequent antibiotics susceptibility assay showed that the deletion of icd, rpsF, and iscS significantly increased OXY sensitivity. Moreover, the exogenous addition of the crude OMV fractions of overexpressed recombinant proteins in E. coli with rRpsF, rIcd, rIscS, rOmpA, rPepA, rFrdA, and rRplQ demonstrated that these proteins promoted the OXY resistance of A. hydrophila. Overall, our results indicate the important protective role of OMVs in antibiotic resistance in A. hydrophila and provide novel insights on bacterial antibiotic resistance mechanisms.


Asunto(s)
Aeromonas hydrophila , Oxitetraciclina , Proteínas de la Membrana Bacteriana Externa/metabolismo , Proteínas Bacterianas/metabolismo , Farmacorresistencia Bacteriana , Escherichia coli/metabolismo , Oxitetraciclina/metabolismo , Proteómica/métodos
19.
AMB Express ; 12(1): 76, 2022 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-35705721

RESUMEN

Canine parvovirus-2 (CPV-2) infection causes serious multisystemic disease in dogs and many animal species worldwide. Previously, a monoclonal antibody (MAb) of CPV-2, 10H4, showed high neutralizing activity and therapeutic effect against CPV-2 in dogs. However, the application of mouse MAb is limited in other animals due to immune rejection. Here, the variable regions of the heavy and light chains of 10H4 were cloned and ligated with constant canine antibody regions to produce a canine-derived chimeric MAb 11D9, in a CHO-S cell expression system. The cell supernatant of the CHO cell line 11D9 exhibited a HI titer of 1:2560 against all the variants of CPV-2 (new CPV-2a, new CPV-2b, and CPV-2c), and had the same average neutralization titer as the new CPV-2a (1:11,046.5) and new CPV-2b (1:11,046.5) variants, which was slightly higher than that of CPV-2c variants (1:10,615.7). In animal experiment, the treatment of chimeric MAb 11D9 had a high therapeutic effect in beagles infected with the new CPV-2a. Overall, the canine-derived chimeric MAb 11D9 produced by CHO-S cells showed a high HI and neutralization titer against CPV-2 and the therapeutic effects against the new CPV-2a in beagles, providing potential for the prevention or treatment of CPV-2 infections in dogs.

20.
Mol Cell Proteomics ; 21(9): 100248, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35605723

RESUMEN

Protein lysine acetylation (Kac) modification plays important roles in diverse physiological functions. However, there is little evidence on the role of Kac modification in bacterial antibiotic resistance. Here, we compared the differential expressions of whole-cell proteins and Kac peptides in oxytetracycline sensitive and oxytetracycline resistance (OXYR) strains of Aeromonas hydrophila using quantitative proteomics technologies. We observed a porin family protein Aha1 downregulated in the OXYR strain, which may have an important role in the OXY resistance. Interestingly, seven of eight Kac peptides of Aha1 decreased abundance in OXYR as well. Microbiologic assays showed that the K57R, K187R, and K197R Aha1 mutants significantly increased antibiotic resistance to OXY and reduced the intracellular OXY accumulation in OXY stress. Moreover, these Aha1 mutants displayed multidrug resistance features to tetracyclines and ß-lactam antibiotics. The 3D model prediction showed that the Kac states of K57, K187, and K197 sites located at the extracellular pore vestibule of Aha1 may be involved in the uptake of specific types of antibiotics. Overall, our results indicate a novel antibiotic resistance mechanism mediated by Kac modification, which may provide a clue for the development of antibiotic therapy strategies.


Asunto(s)
Aeromonas hydrophila , Oxitetraciclina , Acetilación , Antibacterianos/metabolismo , Antibacterianos/farmacología , Farmacorresistencia Bacteriana , Lisina/metabolismo , Oxitetraciclina/metabolismo , Porinas/metabolismo , beta-Lactamas/farmacología
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