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1.
J Med Microbiol ; 73(5)2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38743468

RESUMO

Introduction. Innovative antifungal therapies are of crucial importance to combat the potentially life-threatening infections linked to the multidrug-resistant fungal pathogen Candida auris. Induction of regulated cell death, apoptosis, could provide an outline for future therapeutics. Human antimicrobial peptides (AMPs), well-known antifungal compounds, have shown the ability to induce apoptosis in pathogenic fungi.Hypothesis/Gap Statement . Although it is known that AMPs possess antifungal activity against C. auris, their ability to induce apoptosis requires further investigations.Aim. This study evaluated the effects of AMPs on the induction of apoptosis in C. auris.Methods. Human neutrophil peptide-1 (HNP-1), human ß-Defensins-3 (hBD-3) and human salivary histatin 5 (His 5) were assessed against two clinical C. auris isolates. Apoptosis hallmarks were examined using FITC-Annexin V/PI double labelling assay and terminal deoxynucleotidyl transferase deoxynucleotidyl transferase nick-end labelling (TUNEL) to detect phosphatidylserine externalization and DNA fragmentation, respectively. Then, several intracellular triggers were studied using JC-10 staining, spectrophotometric assay and 2',7'-dichlorofluorescin diacetate staining to measure the mitochondrial membrane potential, cytochrome-c release and reactive oxygen species (ROS) production, respectively.Results and conclusion. FITC-Annexin V/PI staining and TUNEL analysis revealed that exposure of C. auris cells to HNP-1 and hBD-3 triggered both early and late apoptosis, while His 5 caused significant necrosis. Furthermore, HNP-1 and hBD-3 induced significant mitochondrial membrane depolarization, which resulted in substantial cytochrome c release. In contrast to His 5, which showed minimal mitochondrial depolarization and no cytochrome c release. At last, all peptides significantly increased ROS production, which is related to both types of cell death. Therefore, these peptides represent promising and effective antifungal agents for treating invasive infections caused by multidrug-resistant C. auris.


Assuntos
Antifúngicos , Apoptose , Candida auris , Histatinas , Espécies Reativas de Oxigênio , Apoptose/efeitos dos fármacos , Humanos , Antifúngicos/farmacologia , Histatinas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Candida auris/efeitos dos fármacos , beta-Defensinas/farmacologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , alfa-Defensinas/farmacologia , Testes de Sensibilidade Microbiana , Peptídeos Antimicrobianos/farmacologia , Peptídeos Antimicrobianos/química , Citocromos c/metabolismo , Fragmentação do DNA/efeitos dos fármacos , Candidíase/tratamento farmacológico , Candidíase/microbiologia
2.
Life Sci Alliance ; 7(6)2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38580392

RESUMO

Antimicrobial peptides (AMPs) are host defense effectors with potent neutralizing and immunomodulatory functions against invasive pathogens. The AMPs α-Defensin 1-3/DEFA1A3 participate in innate immune responses and influence patient outcomes in various diseases. DNA copy-number variations in DEFA1A3 have been associated with severity and outcomes in infectious diseases including urinary tract infections (UTIs). Specifically, children with lower DNA copy numbers were more susceptible to UTIs. The mechanism of action by which α-Defensin 1-3/DEFA1A3 copy-number variations lead to UTI susceptibility remains to be explored. In this study, we use a previously characterized transgenic knock-in of the human DEFA1A3 gene mouse to dissect α-Defensin 1-3 gene dose-dependent antimicrobial and immunomodulatory roles during uropathogenic Escherichia coli (UPEC) UTI. We elucidate the relationship between kidney neutrophil- and collecting duct intercalated cell-derived α-Defensin 1-3/DEFA1A3 expression and UTI. We further describe cooperative effects between α-Defensin 1-3 and other AMPs that potentiate the neutralizing activity against UPEC. Cumulatively, we demonstrate that DEFA1A3 directly protects against UPEC meanwhile impacting pro-inflammatory innate immune responses in a gene dosage-dependent manner.


Assuntos
Infecções Urinárias , alfa-Defensinas , Animais , Humanos , Camundongos , alfa-Defensinas/genética , DNA , Dosagem de Genes , Imunidade Inata/genética , Rim/metabolismo , Peptídeos Cíclicos/genética , Infecções Urinárias/genética , Infecções Urinárias/metabolismo
3.
ACS Sens ; 9(4): 1775-1784, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38591344

RESUMO

Periprosthetic joint infections (PJIs) pose a significant challenge in orthopedic surgery, particularly total joint arthroplasty (TJA), due to the potential for implant failure and increased patient morbidity. Early and accurate detection of PJIs is crucial for timely intervention and better patient prognosis. Herein, we successfully screened a high-affinity aptamer targeting alpha-defensin complex human neutrophil protein 1-3 (HNP 1-3; potential PJI biomarkers in synovial fluid [SF]) for the first time using systematic evolution of ligands by exponential enrichment (SELEX) on an integrated microfluidic platform. The compact microfluidic device enabled efficient screening, with each round completed within <2 h, comprising five rounds of positive selection, two rounds of negative selection, and one round of competitive selection. A novel one-aptamer-one-antibody assay was further developed from the optimal aptamer screened, and it could accurately quantify HNP 1-3 in SF within 3 h with only ∼50 µL of SF. The assay demonstrated strong binding affinity and specificity for the target protein in SF. Thirteen PJI SF samples were accurately diagnosed and the assay was accurate over a wide dynamic range (0.32-100 mg/L). This study has showcased a rapid and accurate diagnostic tool for PJI detection, which should see widespread use in the clinic, holding promise for potential analytical applications in orthopedic surgery and improving patient care.


Assuntos
Aptâmeros de Nucleotídeos , Infecções Relacionadas à Prótese , Técnica de Seleção de Aptâmeros , Líquido Sinovial , alfa-Defensinas , alfa-Defensinas/análise , Humanos , Infecções Relacionadas à Prótese/diagnóstico , Técnica de Seleção de Aptâmeros/métodos , Aptâmeros de Nucleotídeos/química , Líquido Sinovial/química , Dispositivos Lab-On-A-Chip , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos
4.
Microbiol Spectr ; 12(4): e0035824, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38441982

RESUMO

The use of immune compounds as antimicrobial adjuvants is a classic idea recovering timeliness in the current antibiotic resistance scenario. However, the activity of certain antimicrobial peptides against ESKAPE Gram-negatives has not been sufficiently investigated. The objective of this study was to determine the activities of human defensins HNP-1 and hBD-3 alone or combined with permeabilizing/peptidoglycan-targeting agents against clinical ESKAPE Gram-negatives [Acinetobacter baumannii (AB), Enterobacter cloacae (EC), Klebsiella pneumoniae (KP), and acute/chronic Pseudomonas aeruginosa (PA)]. Lethal concentrations (LCs) of HNP-1 and hBD-3 were determined in four collections of multidrug resistant EC, AB, KP, and PA clinical strains (10-36 isolates depending on the collection). These defensins act through membrane permeabilization plus peptidoglycan building blockade, enabling that alterations in peptidoglycan recycling may increase their activity, which is why different recycling-defective mutants were also included. Combinations with physiological lysozyme and subinhibitory colistin for bactericidal activities determination, and with meropenem for minimum inhibitory concentrations (MICs), were also assessed. HNP-1 showed undetectable activity (LC > 32 mg/L for all strains). hBD-3 showed appreciable activities: LC ranges 2-16, 8-8, 8->32, and 8->32 mg/L for AB, EC, KP, and PA, being PA strains from cystic fibrosis significantly more resistant than acute origin ones. None of the peptidoglycan recycling-defective mutants showed greater susceptibility to HNP-1/hBD-3. Combination with colistin or lysozyme did not change their bactericidal power, and virtually neither did meropenem + hBD-3 compared to meropenem MICs. This is the first study comparatively analyzing the HNP-1/hBD-3 activities against the ESKAPE Gram-negatives, and demonstrates interesting bactericidal capacities of hBD-3 mostly against AB and EC. IMPORTANCE: In the current scenario of critical need for new antimicrobials against multidrug-resistant bacteria, all options must be considered, including classic ideas such as the use of purified immune compounds. However, information regarding the activity of certain human defensins against ESKAPE Gram-negatives was incomplete. This is the first study comparatively assessing the in vitro activity of two membrane-permeabilizing/peptidoglycan construction-blocking defensins (HNP-1 and hBD-3) against relevant clinical collections of ESKAPE Gram-negatives, alone or in combination with permeabilizers, additional peptidoglycan-targeting attacks, or the blockade of its recycling. Our data suggest that hBD-3 has a notable bactericidal activity against multidrug-resistant Acinetobacter baumannii and Enterobacter cloacae strains that should be considered as potential adjuvant option. Our results suggest for the first time an increased resistance of Pseudomonas aeruginosa strains from chronic infection compared to acute origin ones, and provide new clues about the predominant mode of action of hBD-3 against Gram-negatives (permeabilization rather than peptidoglycan-targeting).


Assuntos
Anti-Infecciosos , Infecções por Pseudomonas , alfa-Defensinas , Humanos , Colistina/farmacologia , Muramidase/farmacologia , Peptidoglicano , Meropeném/farmacologia , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Testes de Sensibilidade Microbiana , Farmacorresistência Bacteriana Múltipla
5.
Physiol Rep ; 12(3): e15945, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38328863

RESUMO

Antimicrobial peptides (AMPs) constitute a complex network of 10-100 amino acid sequence molecules widely distributed in nature. While over 300 AMPs have been described in mammals, cathelicidins and defensins remain the most extensively studied. Some publications have explored the role of AMPs in COVID-19, but these findings are preliminary, and in vivo studies are still lacking. In this study, we report the plasma levels of five AMPs (LL-37, α-defensin 1, α-defensin 3, ß-defensin 1, and ß-defensin 3), using the ELISA technique (MyBioSource, San Diego, CA, United States, kits MBS2601339 (beta-defensin 1), MBS2602513 (beta-defensin 3), MBS703879 (alpha-defensin 1), MBS706289 (alpha-defensin 3), MBS7234921 (LL37)), and the measurement of six cytokines (tumor necrosis factor-α, interleukin-1ß, interleukin-6, interleukin-10, interferon-γ, and monocyte chemoattractant protein-1), through the magnetic bead immunoassay Milliplex® and the MAGPIX® System (MilliporeSigma, Darmstadt, Germany, kit HCYTOMAG-60 K (cytokines)), in 15 healthy volunteers, 36 COVID-19 patients without Acute Kidney Injury (AKI) and 17 COVID-19 patients with AKI. We found increased levels of α-defensin 1, α-defensin 3 and ß-defensin 3, in our COVID-19 population, when compared to healthy controls, along with higher levels of interleukin-6, interleukin-10, interferon-γ, and monocyte chemoattractant protein-1. These findings suggest that these AMPs and cytokines may play a crucial role in the systemic inflammatory response and tissue damage characterizing severe COVID-19. The levels of α-defensin 1 and α-defensin 3 were significantly higher in COVID-19 AKI group in comparison to the non-AKI group. Furthermore, IL-10 and the product IL-10 × IL-1B showed excellent performance in discriminating AKI, with AUCs of 0.86 and 0.88, respectively. Among patients with COVID-19, AMPs may play a key role in the inflammation process and disease progression. Additionally, α-defensin 1 and α-defensin 3 may mediate the AKI process in these patients, representing an opportunity for further research and potential therapeutic alternatives in the future.


Assuntos
Injúria Renal Aguda , COVID-19 , alfa-Defensinas , beta-Defensinas , Animais , Humanos , beta-Defensinas/metabolismo , Interleucina-10 , Peptídeos Catiônicos Antimicrobianos/metabolismo , Quimiocina CCL2 , SARS-CoV-2/metabolismo , Peptídeos Antimicrobianos , Interleucina-6 , Interferon gama , Estado Terminal , Citocinas/metabolismo , Biomarcadores , Injúria Renal Aguda/diagnóstico , Mamíferos/metabolismo
6.
Molecules ; 29(3)2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38338475

RESUMO

The global increase in antibiotic consumption is related to increased adverse effects, such as antibiotic-associated diarrhea (AAD). This study investigated the chemical properties of Zingiber officinale Rosc (ZO) extract and its ameliorative effects using a lincomycin-induced AAD mouse model. Intestinal tissues were evaluated for the expression of lysozyme, claudin-1, and α-defensin-1, which are associated with intestinal homeostasis. The cecum was analyzed to assess the concentration of short-chain fatty acids (SCFAs). The chemical properties analysis of ZO extracts revealed the levels of total neutral sugars, acidic sugars, proteins, and polyphenols to be 86.4%, 8.8%, 4.0%, and 0.8%, respectively. Furthermore, the monosaccharide composition of ZO was determined to include glucose (97.3%) and galactose (2.7%). ZO extract administration ameliorated the impact of AAD and associated weight loss, and water intake also returned to normal. Moreover, treatment with ZO extract restored the expression levels of lysozyme, α-defensin-1, and claudin-1 to normal levels. The decreased SCFA levels due to induced AAD showed a return to normal levels. The results indicate that ZO extract improved AAD, strengthened the intestinal barrier, and normalized SCFA levels, showing that ZO extract possesses intestinal-function strengthening effects.


Assuntos
Zingiber officinale , alfa-Defensinas , Camundongos , Animais , Muramidase , Claudina-1/genética , Diarreia/induzido quimicamente , Diarreia/tratamento farmacológico , Antibacterianos/efeitos adversos , Açúcares
7.
J Vet Med Sci ; 86(3): 277-284, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38267031

RESUMO

The mechanism by which the neonicotinoid pesticide clothianidin (CLO) disrupts the intestinal microbiota of experimental animals is unknown. We focused on α-defensins, which are regulators of the intestinal microbiota. Subchronic exposure to CLO induced dysbiosis and reduced short-chain fatty acid-producing bacteria in the intestinal microbiota of mice. Levels of cryptdin-1 (Crp1, a major α-defensin in mice) in feces and cecal contents were lower in the CLO-exposed groups than in control. In Crp1 immunostaining, Paneth cells in the jejunum and ileum of the no-observed-adverse-effect-level CLO-exposed group showed a stronger positive signal than control, likely due to the suppression of Crp1 release. Our results showed that CLO exposure suppresses α-defensin secretion from Paneth cells as part of the mechanism underlying CLO-induced dysbiosis.


Assuntos
Microbioma Gastrointestinal , Guanidinas , Praguicidas , Doenças dos Roedores , Tiazóis , alfa-Defensinas , Camundongos , Animais , Praguicidas/toxicidade , Disbiose/induzido quimicamente , Disbiose/microbiologia , Disbiose/veterinária , Neonicotinoides/toxicidade , Celulas de Paneth/microbiologia
8.
Biol Pharm Bull ; 47(1): 159-165, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38171775

RESUMO

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) are used to treat non-small cell lung cancer with EGFR mutations. However, first-generation erlotinib and second-generation afatinib often cause diarrhea, which may develop because of the association between EGFR-TKIs and the chloride channel or abnormalities in the intestinal microbiota due to disruption of the intestinal immune system. As reports on the effects of EGFR-TKIs on intestinal immunity are lacking, we aimed to determine whether the intestinal immune system is involved in the molecular effects of EGFR-TKIs on chloride channels using Caco-2 cells. Initially, we evaluated the association of chloride channels with α-defensin 5 (DEFA5), a marker of intestinal immunity. Erlotinib and afatinib significantly increased the extracellularly secreted DEFA5 level and autophagy-related 16-like 1 and X-box binding protein 1 transcript levels, indicative of enhanced granule exocytosis. Conversely, intracellular DEFA5 and Toll-like receptor 4 protein expression and tumor necrosis factor-α transcript levels decreased significantly, suggesting that Toll-like receptor 4 suppression repressed DEFA5 production. Furthermore, among the chloride channels, DEFA5 was found to significantly increase the transcript levels of cystic fibrosis transmembrane conductance regulators. These results indicate that DEFA5 plays a significant role in the mechanism of chloride channel-mediated diarrhea induced by EGFR-TKIs. Therefore, we successfully elucidated the potential host action of DEFA5 in cancer therapy for the first time.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , alfa-Defensinas , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Afatinib/efeitos adversos , Cloridrato de Erlotinib/efeitos adversos , Neoplasias Pulmonares/metabolismo , Receptor 4 Toll-Like/metabolismo , alfa-Defensinas/metabolismo , Inibidores de Proteínas Quinases/efeitos adversos , Células CACO-2 , Cloretos/metabolismo , Receptores ErbB/metabolismo , Mutação , Diarreia/induzido quimicamente , Canais de Cloreto/genética
9.
J Immunol Methods ; 525: 113599, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38081407

RESUMO

Intestinal transplantation is the definitive treatment for intestinal failure. However, tissue rejection and graft-versus-host disease are relatively common complications, necessitating aggressive immunosuppression that can itself pose further complications. Tracking intraluminal markers in ileal effluent from standard ileostomies may present a noninvasive and sensitive way to detect developing pathology within the intestinal graft. This would be an improvement compared to current assessments, which are limited by poor sensitivity and specificity, contributing to under or over-immunosuppression, respectively, and by the need for invasive biopsies. Herein, we report an approach to reproducibly analyze ileal fluid obtained through stoma sampling for antimicrobial peptide/protein concentrations, reasoning that these molecules may provide an assessment of intestinal homeostasis and levels of intestinal inflammation over time. Concentrations of lysozyme (LYZ), myeloperoxidase (MPO), calprotectin (S100A8/A9) and ß-defensin 2 (DEFB2) were assessed using adaptations of commercially available enzyme-linked immunosorbent assays (ELISAs). The concentration of α-defensin 5 (DEFA5) was assessed using a newly developed sandwich ELISA. Our data support that with proper preparation of ileal effluent specimens, precise and replicable determination of antimicrobial peptide/protein concentrations can be achieved for each of these target molecules via ELISA. This approach may prove to be reliable as a clinically useful assessment of intestinal homeostasis over time for patients with ileostomies.


Assuntos
Peptídeos Antimicrobianos , alfa-Defensinas , Humanos , Intestinos , Ensaio de Imunoadsorção Enzimática , Biópsia
10.
J Arthroplasty ; 39(3): 787-794.e1, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37611677

RESUMO

BACKGROUND: Previous studies have speculated on elevated synovial inflammatory markers in patients undergoing surgical revision for total hip arthroplasty (THA) dislocation. However, this assumption is based on small patient series and a full investigation according to International Consensus Meeting (ICM) criteria has not yet been performed. METHODS: Patients who had aseptic THA dislocation indicated for revision surgery were identified retrospectively. Only patients who had available diagnostic workup according to ICM 2018 criteria, including preoperative and intraoperative parameters, were included. For comparison, we analyzed a matched cohort of patients indicated for aseptic THA revision for other conditions. The 2 cohorts each consisted of 55 patients and were not different regarding age, sex, BMI, or implant fixation. RESULTS: There was no difference in synovial white blood cell count (2,238 ± 2,544 versus 2,533 ± 3,448 c/µL; P = .601), alpha-defensin quotient (0.14 ± 0.11 versus 0.19 ± 0.28; P = .207), or polymorphonuclear neutrophil percentage (% PMN) (36.7 ± 22.6 versus 31.3 ± 24.5%; P = .312) between the groups. In the dislocation cohort, 20% of patients had a synovial white blood cell count of 3,000 c/µL or higher, compared with 18% in the control cohort. However, all patients in the dislocation cohort were below the cutoff for alpha-defensin or % PMN. CONCLUSION: In patients who have aseptic THA dislocation, synovial inflammatory markers are not elevated compared with patients undergoing aseptic revision for other complications. A detailed preoperative analysis of synovial inflammatory markers using ICM criteria appears critical in patients who have a THA dislocation to exclude periprosthetic joint infection. LEVEL OF EVIDENCE: Level III, retrospective, comparative study.


Assuntos
Artroplastia de Quadril , Luxação do Quadril , Luxações Articulares , Infecções Relacionadas à Prótese , alfa-Defensinas , Humanos , Artroplastia de Quadril/efeitos adversos , Estudos Retrospectivos , Infecções Relacionadas à Prótese/etiologia , Líquido Sinovial , Reoperação/efeitos adversos , Luxação do Quadril/complicações
11.
Proteomics ; 24(3-4): e2300202, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37541286

RESUMO

Parkinson's disease (PD) is a complex neurodegenerative disease with motor and non-motor symptoms. Diagnosis is complicated by lack of reliable biomarkers. To individuate peptides and/or proteins with diagnostic potential for early diagnosis, severity and discrimination from similar pathologies, the salivary proteome in 36 PD patients was investigated in comparison with 36 healthy controls (HC) and 35 Alzheimer's disease (AD) patients. A top-down platform based on HPLC-ESI-IT-MS allowed characterizing and quantifying intact peptides, small proteins and their PTMs (overall 51). The three groups showed significantly different protein profiles, PD showed the highest levels of cystatin SA and antileukoproteinase and the lowest of cystatin SN and some statherin proteoforms. HC exhibited the lowest abundance of thymosin ß4, short S100A9, cystatin A, and dimeric cystatin B. AD patients showed the highest abundance of α-defensins and short oxidized S100A9. Moreover, different proteoforms of the same protein, as S-cysteinylated and S-glutathionylated cystatin B, showed opposite trends in the two pathological groups. Statherin, cystatins SA and SN classified accurately PD from HC and AD subjects. α-defensins, histatin 1, oxidized S100A9, and P-B fragments were the best classifying factors between PD and AD patients. Interestingly statherin and thymosin ß4 correlated with defective olfactory functions in PD patients. All these outcomes highlighted implications of specific proteoforms involved in the innate-immune response and inflammation regulation at oral and systemic level, suggesting a possible panel of molecular and clinical markers suitable to recognize subjects affected by PD.


Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Doença de Parkinson , alfa-Defensinas , Humanos , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/metabolismo , Cistatina B/análise , Cistatina B/metabolismo , Proteômica/métodos , Doença de Parkinson/diagnóstico , Doença de Parkinson/metabolismo , Doenças Neurodegenerativas/metabolismo , alfa-Defensinas/análise , alfa-Defensinas/metabolismo , Saliva/química , Proteínas e Peptídeos Salivares/metabolismo , Fatores de Transcrição/metabolismo , Biomarcadores/análise
12.
Radiat Res ; 201(2): 160-173, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38124379

RESUMO

The effect of ionizing radiation on the gastrointestinal tract is a common complication of abdominal and pelvic radiotherapy. However, the pathological features of radiation enteropathy and its effective medical intervention regimen is still a global challenge. Here, we explored the role and mechanism of enteric alpha-defensins (EαDs) in protecting against radiation enteropathy. To address this, we utilized EαDs-deficiency mice, in which the matrix metallopeptidase 7 to activate Paneth cell α-defensins was knockout (KO) mice, and the complementary wild-type (WT) control mice for this study. Remarkably, the KO mice were more susceptible to 5.0 Gy total-body irradiation, resulting in worse clinic scores and lower survival rate, compared with the wild-type mice. Histological examination indicated that the KO mice were subjected to slow recovery of intestinal villus and mucosa function, characterized by the reduced expression of TFF3, Glut1 and Muc2. In addition, compared with the wild-type controls, the KO mice experienced serious inflammation response in intestinal tissue, indicated by the remarkably increased expression level of IL-1ß, IL-6 and IL-12. Using high-throughput sequencing analysis, we found that the intestinal bacterial community of the KO mice was more prone to dysbiosis than that of the WT mice, with significantly increased abundance of opportunistic pathogenic bacteria, such as Streptococcus sp. and Escherichia-Shigella sp., whereas remarkably decreased probiotics harboring Lactobacillus sp., Desulfovibrio sp. etc. Fecal metabolomics analysis indicated that the relative abundance of 31 metabolites arose significantly different between WT and KO mice on day 10 after radiation exposure. A subset of differential metabolites to regulate host metabolism and immunity, such as acetic acid, acetate, butanoic acid, was negatively correlated with the alteration of gut microbiota in the irradiated KO mice. This study provides new insight into EαDs contribution to the recovery of radiation-induced intestinal damage, and suggests a potential novel target to prevent the adverse effects of radiotherapy.


Assuntos
Microbioma Gastrointestinal , Lesões por Radiação , alfa-Defensinas , Camundongos , Animais , alfa-Defensinas/genética , alfa-Defensinas/metabolismo , Microbioma Gastrointestinal/efeitos da radiação , Intestinos , Mucosa Intestinal/metabolismo , Fezes/microbiologia , Lesões por Radiação/metabolismo , Camundongos Knockout , Camundongos Endogâmicos C57BL
13.
Respir Res ; 24(1): 309, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38082274

RESUMO

Alpha-1-antitrypsin deficiency (AATD) is a genetic disorder associated with a 5-tenfold decrease in lung levels of alpha-1-antitrypsin (AAT) and an increased risk for obstructive lung disease. α-defensins are cationic broad-spectrum cytotoxic and pro-inflammatory peptides found in the azurophilic granules of neutrophils. The concentration of α-defensins is less than 30 nM in the bronchoalveolar lavage fluid of healthy controls but is up to 6 µM in AATD individuals with significant lung function impairment. Alveolar macrophages are generally classified into pro-inflammatory (M1) or anti-inflammatory (M2) subsets that play distinct roles in the initiation and resolution of inflammation. Therefore, monocyte-macrophage differentiation should be tightly controlled to maintain lung integrity. In this study, we determined the effect of α-defensins on monocyte-macrophage differentiation and identified the molecular mechanism of this effect. The results of this study demonstrate that 2.5 µM of α-defensins inhibit the phosphorylation of ERK1/2 and STAT3 and suppress the expression of M2 macrophage markers, CD163 and CD206. In addition, a scratch assay shows that the high concentration of α-defensins inhibits cell movement by ~ 50%, and the phagocytosis assay using flow cytometry shows that α-defensins significantly reduce the bacterial phagocytosis rate of monocyte-derived macrophages (MDMs). To examine whether exogenous AAT is able to alleviate the inhibitory effect of α-defensins on macrophage function, we incubated MDMs with AAT prior to α-defensin treatment and demonstrate that AAT improves the migratory ability and phagocytic ability of MDMs compared with MDMs incubated only with α-defensins. Taken together, this study suggests that a high concentration of α-defensins inhibits the activation of ERK/STAT3 signaling, negatively regulates the expression of M2 macrophage markers, and impairs innate immune function of macrophages.


Assuntos
Deficiência de alfa 1-Antitripsina , alfa-Defensinas , Humanos , Monócitos/metabolismo , alfa-Defensinas/metabolismo , Macrófagos/metabolismo , Deficiência de alfa 1-Antitripsina/metabolismo , Macrófagos Alveolares/metabolismo , Fator de Transcrição STAT3/metabolismo
14.
Proc Natl Acad Sci U S A ; 120(47): e2312453120, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37956278

RESUMO

To mediate critical host-microbe interactions in the human small intestine, Paneth cells constitutively produce abundant levels of α-defensins and other antimicrobials. We report that the expression profile of these antimicrobials is dramatically askew in human small intestinal organoids (enteroids) as compared to that in paired tissue from which they are derived, with a reduction of α-defensins to nearly undetectable levels. Murine enteroids, however, recapitulate the expression profile of Paneth cell α-defensins seen in tissue. WNT/TCF signaling has been found to be instrumental in the regulation of α-defensins, yet in human enteroids exogenous stimulation of WNT signaling appears insufficient to rescue α-defensin expression. By stark contrast, forkhead box O (FOXO) inhibitor AS1842856 induced the expression of α-defensin mRNA in enteroids by >100,000-fold, restoring DEFA5 and DEFA6 to levels comparable to those found in primary human tissue. These results newly identify FOXO signaling as a pathway of biological and potentially therapeutic relevance for the regulation of human Paneth cell α-defensins in health and disease.


Assuntos
Anti-Infecciosos , alfa-Defensinas , Humanos , Animais , Camundongos , alfa-Defensinas/genética , alfa-Defensinas/farmacologia , alfa-Defensinas/metabolismo , Intestinos , Intestino Delgado/metabolismo , Celulas de Paneth/metabolismo , Anti-Infecciosos/metabolismo , Organoides/metabolismo
15.
PLoS One ; 18(11): e0294041, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37988380

RESUMO

Human α-defensin 5 (HD5) is a cationic antimicrobial peptide exhibiting a wide range of antimicrobial activities. It plays an important role in mucosal immunity of the small intestine. HD5 exerts its bactericidal activities through multiple mechanisms, one of which involves HD5 inducing the formation of pores in the bacterial membrane, subsequently allowing the peptide to enter the bacterial cytoplasm. Nevertheless, the precise molecular intricacies underlying its bactericidal mechanisms remain inadequately understood. In this work, the Potential of Mean Force (PMF) was computed to delve into the energetic properties governing the movement of HD5 across the lipopolysaccharide (LPS) membrane, which is a representative model of the gram-negative bacterial membrane. Our findings indicate that the most favorable free energy is attained when HD5 binds to the surface of the LPS membrane. This favorable interaction is primarily driven by the strong interactions between arginine residues in HD5 and the charged head groups of LPS, serving as the predominant forces facilitating the adhesion of HD5 to the membrane. Our analysis reveals that a dimeric form of HD5 alone is sufficient to create a water-filled channel in the membrane; however, achieving the complete lysis of the gram-negative bacterial membrane requires higher-order oligomerization of HD5. Our results suggest that HD5 employs the toroidal pore formation mechanism to disrupt the integrity of the LPS membrane. Furthermore, we identified that the primary energy barrier obstructing HD5 from traversing the membrane is localized within the hydrophobic core of the membrane, which is also observed for other defensins. Additionally, our study demonstrates that a mixture of HD5-LPS leads to a thinning of the membrane. Taken together, this work provides a deeper insight into the molecular intricacies governing the behavior of HD5 as it translocates through the gram-negative bacterial membrane.


Assuntos
alfa-Defensinas , Humanos , alfa-Defensinas/metabolismo , Simulação de Dinâmica Molecular , Lipopolissacarídeos/farmacologia , Antibacterianos
16.
Sci Rep ; 13(1): 17499, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37840103

RESUMO

Human neutrophil peptides (HNPs) can induce cell proliferation and activation so their growth promoting activities may have potential clinical benefit. This study investigated the effects of HNPs on human dermal fibroblasts. Differential gene expression in HNP-treated cells and genes involved in regulating intracellular pathways were explored. Dermal fibroblasts were isolated from healthy neonatal foreskin and treated with HNPs in 2D and 3D cell culture systems. The expression of cell proliferation (Ki-67) gene and cell activation (COL1A1) gene plus their proteins was measured. Differential gene expression was determined using RNA-seq, and upregulated and downregulated genes were mapped onto intracellular pathways by KEGG analysis and Gene Ontology databases. HNPs significantly increased cell proliferation without cytotoxicity whilst HNP1 enhanced expression of COL1A1 and type I collagen production in 2D cells and 3D spheroids. RNA-sequencing analysis showed gene clustering with clear separation between HNP1-treated and control groups. A heatmap of top 50 differentially expressed genes was consistent among HNP1-treated samples. Most upregulated genes were associated with cell proliferation and activation as mapped into intracellular pathways whilst most downregulated genes belonged to steroid/arachidonic acid metabolism and inflammatory signaling pathways. HNP1 increased cell proliferation and activation but reduced lipid metabolism and inflammation.


Assuntos
Neutrófilos , alfa-Defensinas , Recém-Nascido , Humanos , Neutrófilos/metabolismo , alfa-Defensinas/metabolismo , Transdução de Sinais , Pele/metabolismo , Fibroblastos/metabolismo
17.
Med Sci Monit ; 29: e940842, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37814443

RESUMO

BACKGROUND This prospective, double-blind study investigated the clinical diagnostic value of synovial fluid S100 calcium-binding protein A8 (S100A8) and S100 calcium-binding protein A9 (S100A9) in periprosthetic joint infection (PJI) and investigated the subtypes of a-defensin that have diagnostic value for PJI. MATERIAL AND METHODS Synovial fluid samples were collected from 82 patients with suspected PJI after total joint arthroplasty. Patients were divided into a PJI group (n=39) and non-PJI group (n=43). Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry was used to determine S100A8, S100A9, alpha-defensin, and internal reference standards in synovial fluid. The receiver operating characteristic (ROC) curve was used to analyze the diagnostic efficiency of S100A8, S100A9, and alpha-defensin for PJI, as well as the diagnostic value in combination with common biomarkers of infection. RESULTS S100A8, 3 variants of S100A9, and 3 alpha-defensins (human neutrophil peptides [HNP]1-3) in synovial fluid were significantly higher in the PJI group than in the non-PJI group (P<0.001). The sensitivity, specificity, and the area under ROC curve (AUC) for diagnosing PJI were 97.4%, 86.0%, and 0.964 (95% CI: 0.929-0.998), respectively, for synovial fluid S100A8; 87.2%, 88.4% and 0.902 (95% CI: 0.823-0.980), respectively, for S100A9; and 89.7%, 83.7%, and 0.933 (95% CI: 0.884-0.982), respectively, for HNP1-3. The diagnostic efficiency was improved when combined with synovial fluid white blood cell count and percentage of polymorphonuclear neutrophils. CONCLUSIONS Synovial fluid S100A8, S100A9, and HNP1-3 have satisfactory diagnostic efficiency for the diagnosis of PJI, which will help clinicians to accurately diagnose PJI.


Assuntos
Artrite Infecciosa , Artroplastia de Quadril , Infecções Relacionadas à Prótese , alfa-Defensinas , Humanos , alfa-Defensinas/análise , Líquido Sinovial/metabolismo , Infecções Relacionadas à Prótese/diagnóstico , Estudos Prospectivos , Método Duplo-Cego , Biomarcadores , Artrite Infecciosa/diagnóstico , Artrite Infecciosa/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Sensibilidade e Especificidade , Artroplastia de Quadril/efeitos adversos
18.
Protein Pept Lett ; 30(10): 830-840, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37861034

RESUMO

The antibacterial and antiviral functions of human defensin 5 lay the foundation for its role as a core host protective component. In addition, HD5 also has the function of inhibiting tumor proliferation and immune regulation. However, everything has two sides; cytotoxic and proinflammatory properties may exist, while HD5 performs physiological functions. Accordingly, the modification and engineering of HD5 are particularly important. Therefore, this review summarizes the role of HD5 in various aspects of host defense, as well as modification of HD5 to ameliorate the biological activity, with a view to promoting the clinical use of HD5.


Assuntos
alfa-Defensinas , Humanos , alfa-Defensinas/química , alfa-Defensinas/metabolismo , alfa-Defensinas/farmacologia , Antibacterianos
19.
J Drugs Dermatol ; 22(9): 874-880, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37683059

RESUMO

BACKGROUND: Defensins recruit leucine-rich repeat-containing G protein-coupled receptor 6 positive (Lgr6+) stem cells which ultimately regenerate new basal stem cells, healthy keratinocytes, and nascent hair follicles. Thus, defensins are an exciting, novel therapy for the reversal of skin aging. METHODS: This is a multicenter, prospective, open-label clinical trial. Twenty healthy subjects, aged 45-80, with Fitzpatrick skin types II-IV were enrolled in the study. A skin care regimen containing alpha-defensin 5 and beta-defensin 3 were applied to the face twice daily for 12 weeks. This skin care regimen contains a greater percentage of defensins than that already studied.7 All participants underwent imaging at baseline, day 30, day 60, and day 90. Primary endpoints included investigator scoring on the Fitzpatrick-Goldman wrinkle scale and percent improvement in periorbital wrinkles, laxity, pigmentation, erythema, texture, and radiance. Secondary endpoints were investigator Global Aesthetic Improvement Score (GAIS), subject GAIS, and investigator assessment of tolerability. A final subject questionnaire was completed on day 90.  Results: Based on the Fitzpatrick-Goldman wrinkle scale, a statistically significant improvement was noted in both wrinkling and elastosis from baseline to day 90. 30% of subjects were rated as much improved and 50% of subjects were rated as improved on the physician GAIS at the 90 day follow up. Improvements were noted in all aspects of skin quality including wrinkles, laxity, dyschromia, erythema, texture, and radiance.  Conclusion: The enhanced formula containing increased concentrations of alpha-defensin 5 and beta-defensin 3 is a safe and efficacious topical therapy for the treatment of periorbital rhytids. CITATION: Hartman N, Loyal J, Taub A, et al. Clinical trial of alpha and beta defensin skin care regimen for improvement of periocular wrinkles. J Drugs Dermatol. 2023;22(9):874-880. doi:10.36849/JDD.7184.


Assuntos
Transtornos da Pigmentação , Envelhecimento da Pele , alfa-Defensinas , beta-Defensinas , Humanos , Estudos Prospectivos , Higiene da Pele
20.
Front Cell Infect Microbiol ; 13: 1210345, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37529352

RESUMO

Background: Identifying novel biomarkers that are both specific and sensitive to periprosthetic joint infection (PJI) has the potential to improve diagnostic accuracy and ultimately enhance patient outcomes. Therefore, the aim of this systematic review is to identify and evaluate the effectiveness of novel biomarkers for the diagnosis of PJI. Methods: We searched the MEDLINE, EMBASE, PubMed, and Cochrane Library databases from January 1, 2018, to September 30, 2022, using the search terms "periprosthetic joint infection," "prosthetic joint infection," or "periprosthetic infection" as the diagnosis of interest and the target index, combined with the term "marker." We excluded articles that mentioned established biomarkers such as CRP, ESR, Interleukin 6, Alpha defensin, PCT (procalcitonin), and LC (leucocyte cell count). We used the MSIS, ICM, or EBJS criteria for PJI as the reference standard during quality assessment. Results: We collected 19 studies that analyzed fourteen different novel biomarkers. Proteins were the most commonly analyzed biomarkers (nine studies), followed by molecules (three studies), exosomes (two studies), DNA (two studies), interleukins (one study), and lysosomes (one study). Calprotectin was a frequently analyzed and promising marker. In the scenario where the threshold was set at ≥50-mg/mL, the calprotectin point-of-care (POC) performance showed a high sensitivity of 98.1% and a specificity of 95.7%. Conclusion: None of the analyzed biomarkers demonstrated outstanding performance compared to the established parameters used for standardized treatment based on established PJI definitions. Further studies are needed to determine the benefit and usefulness of implementing new biomarkers in diagnostic PJI settings.


Assuntos
Artrite Infecciosa , Infecções Relacionadas à Prótese , alfa-Defensinas , Humanos , Infecções Relacionadas à Prótese/diagnóstico , Biomarcadores , Pró-Calcitonina , Contagem de Leucócitos , alfa-Defensinas/metabolismo , Sensibilidade e Especificidade
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