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Frontiers in Cellular and Infection... 2024Quorum-quenching enzyme Est816 hydrolyzes the lactone rings of -acyl homoserine lactones, effectively blocking the biofilm formation and development of Gram-negative...
INTRODUCTION
Quorum-quenching enzyme Est816 hydrolyzes the lactone rings of -acyl homoserine lactones, effectively blocking the biofilm formation and development of Gram-negative bacteria. However, its applications in the oral field is limited. This study aimed to evaluate the efficacy of enzyme Est816 in combination with antibiotics against periodontitis induced by and .
METHODS
The antimicrobial efficacy of enzyme Est816 in combination with minocycline, metronidazole, and amoxicillin was determined using the minimum inhibitory concentration test. The anti-biofilm effect of enzyme Est816 was assessed using scanning electron microscopy, live/dead bacterial staining, crystal violet staining, and real-time quantitative PCR. Biocompatibility of enzyme Est816 was assessed in human gingival fibroblasts (HGF) by staining. A rat model of periodontitis was established to evaluate the effect of enzyme Est816 combined with minocycline using micro-computed tomography and histological staining.
RESULTS
Compared to minocycline, metronidazole, and amoxicillin treatment alone, simultaneous treatment with enzyme Est816 increased the sensitivity of biofilm bacteria to antibiotics. Enzyme Est816 with minocycline exhibited the highest rate of biofilm clearance and high biocompatibility. Moreover, the combination of enzyme Est816 with antibiotics improved the antibiofilm effects of the antibiotics synergistically, reducing the expression of the virulence factor leukotoxin gene () and fimbria-associated gene (). Likewise, the combination of enzyme Est816 with minocycline exhibited a remarkable inhibitory effect on bone resorption and inflammation damage in a rat model of periodontitis.
DISCUSSION
The combination of enzyme Est816 with antibiotics represents a prospective anti-biofilm strategy with the potential to treat periodontitis.
Topics: Animals; Aggregatibacter actinomycetemcomitans; Biofilms; Anti-Bacterial Agents; Periodontitis; Rats; Microbial Sensitivity Tests; Disease Models, Animal; Humans; Metronidazole; Quorum Sensing; Minocycline; Amoxicillin; Rats, Sprague-Dawley; Male; Fibroblasts; Gingiva
PubMed: 38779565
DOI: 10.3389/fcimb.2024.1368684 -
International Journal of Biological... Jun 2024Gasdermin (GSDM) proteins are executioners of pyroptosis in many species. Gasdermin proteins can be cleaved at their linker region between the amino domain (NT) and...
Gasdermin (GSDM) proteins are executioners of pyroptosis in many species. Gasdermin proteins can be cleaved at their linker region between the amino domain (NT) and carboxyl domain (CT) by enzymes. The released GSDM-NTs bind cell membrane and form pores, thereby leading to the release of cellular components and lytic cell death. GSDM-mediated pyroptosis is considered to play important role in immune responses. However, little is known about the GSDM proteins and GSDM-mediated pyroptosis in birds. In the current study, genes encoding chicken gasdermin A (chGSDMA) and chGSDME were cloned. The cleavage of chGSDMA and chGSDME by chicken caspase-1 (chCASP1), chCASP3 and chCASP7 and the cleavage sites were determined. The chGSDMA-NT obtained form chCASP1-mediated cleavage and chGSDME-NT obtained from chCASP3/chCASP7-mediated cleavage could bind and damage cell membrane and lead to cell death of HEK293 cells. chGSDMA-NT also strongly localized to and formed puncta in nucleus. Besides, both chGSDMA-NT and chGSDME-NT showed growth inhibition and bactericidal activity to bacteria. In chickens challenged with Pasteurella multocida and Salmonella typhimurium, the expression of chGSDMA and chGSDME was upregulated and the activation of chCASP3 and the cleavage of chGSDME were observed. The work provides essential information for expanding our knowledge on pyroptosis in birds.
Topics: Animals; Pyroptosis; Chickens; Humans; HEK293 Cells; Caspases; Pasteurella multocida; Proteolysis; Avian Proteins; Amino Acid Sequence; Gasdermins
PubMed: 38777016
DOI: 10.1016/j.ijbiomac.2024.132476 -
Veterinary Microbiology Jul 2024Glaesserella parasuis (G. parasuis) is the causative agent of porcine Glässer's disease, resulting in high mortality rates in pigs due to excessive inflammation-induced...
Glaesserella parasuis (G. parasuis) is the causative agent of porcine Glässer's disease, resulting in high mortality rates in pigs due to excessive inflammation-induced tissue damage. Previous studies investigating the protective effects of G. parasuis vaccination indicated a possible role of ApoA1 in reflecting disease progression following G. parasuis infection. However, the mechanisms of ApoA1 expression and its role in these infections are not well understood. In this investigation, newborn porcine tracheal (NPTr) epithelial cells infected with G. parasuis were used to elucidate the molecular mechanism and role of ApoA1. The study revealed that the AMPK pathway activation inhibited ApoA1 expression in NPTr cells infected with G. parasuis for the first time. Furthermore, Egr1 was identified as a core transcription factor regulating ApoA1 expression using a CRISPR/Cas9-based system. Importantly, it was discovered that APOA1 protein significantly reduced apoptosis, pyroptosis, necroptosis, and inflammatory factors induced by G. parasuis in vivo. These findings not only enhance our understanding of ApoA1 in response to bacterial infections but also highlight its potential in mitigating tissue damage caused by G. parasuis infection.
Topics: Animals; Swine; Apolipoprotein A-I; Signal Transduction; Early Growth Response Protein 1; Haemophilus parasuis; Swine Diseases; AMP-Activated Protein Kinases; Haemophilus Infections; Epithelial Cells; Gene Expression Regulation; Trachea; Apoptosis; Animals, Newborn
PubMed: 38776767
DOI: 10.1016/j.vetmic.2024.110106 -
PloS One 2024Yaws affects children in tropical regions, while syphilis primarily affects sexually active adults worldwide. Despite various campaigns towards the eradication of yaws...
Prevalence of yaws and syphilis in the Ashanti region of Ghana and occurrence of H. ducreyi, herpes simplex virus 1 and herpes simplex virus 2 in skin lesions associated with treponematoses.
Yaws affects children in tropical regions, while syphilis primarily affects sexually active adults worldwide. Despite various campaigns towards the eradication of yaws and elimination of syphilis, these two diseases are still present in Ghana. The aetiological agents of both diseases, two Treponema pallidum subspecies, are genetically similar. This study aimed to assess the prevalence of these treponematoses and the occurrence of pathogens causing similar skin lesions in the Ashanti region of Ghana. A point-of-care test was used to determine the seroprevalence of the treponematoses. Both yaws and syphilis were identified in the Ashanti region of Ghana. Multiplex PCR was used to identify treponemes and other pathogens that cause similar skin lesions. The results indicated that the seroprevalences of T. pallidum in individuals with yaws-like and syphilis-like lesions were 17.2% and 10.8%, respectively. Multiplex PCR results showed that 9.1%, 1.8% and 0.9% of yaws-like lesions were positive for Haemophilus ducreyi, herpes simplex virus-1 (HSV-1) and T. pallidum respectively. Among syphilis-like lesions, 28.3% were positive for herpes simplex virus -2 (HSV-2) by PCR. To our knowledge, this is the first time HSV-I and HSV-2 have been reported from yaws-like and syphilis-like lesions, respectively, in Ghana. The presence of other organisms apart from T. pallidum in yaws-like and syphilis-like lesions could impede the total healing of these lesions and the full recovery of patients. This may complicate efforts to achieve yaws eradication by 2030 and the elimination of syphilis and warrants updated empirical treatment guidelines for skin ulcer diseases.
Topics: Humans; Ghana; Yaws; Syphilis; Female; Adult; Male; Haemophilus ducreyi; Adolescent; Prevalence; Treponema pallidum; Child; Young Adult; Herpesvirus 1, Human; Middle Aged; Seroepidemiologic Studies; Skin; Child, Preschool; Treponemal Infections
PubMed: 38776332
DOI: 10.1371/journal.pone.0295088 -
PloS One 2024Swine atrophic rhinitis is a disease caused by Pasteurella multocida and Bordetella bronchiseptica that affects pigs. Inactivated vaccines containing the toxins produced...
Swine atrophic rhinitis is a disease caused by Pasteurella multocida and Bordetella bronchiseptica that affects pigs. Inactivated vaccines containing the toxins produced by Pasteurella multocida and Bordetella bronchiseptica have been widely used for the prevention of swine atrophic rhinitis. The efficacy of a vaccine is correlated with the amount of antigen present; however, the protective toxin of P. multocida bound to aluminum hydroxide, which is used as an adjuvant, can hinder the monitoring of the antigen concentration in the vaccine. This study assessed the applicability of a dot immunoassay as an antigen quantification method using monoclonal antibodies. This quantification method was able to detect the antigen with high specificity and sensitivity even when the antigen was bound to the adjuvant, and its application to vaccine products revealed a correlation between the amount of antigen present in the vaccine and the neutralizing antibody titers induced in pigs. The antigen quantification method presented in this study is a simple and sensitive assay capable of quantifying the amount of antigen present in a vaccine that can be used as an alternative quality control measure.
Topics: Animals; Pasteurella multocida; Swine; Rhinitis, Atrophic; Bacterial Vaccines; Aluminum Hydroxide; Adjuvants, Immunologic; Antigens, Bacterial; Swine Diseases; Bordetella bronchiseptica; Antibodies, Bacterial; Pasteurella Infections; Antibodies, Neutralizing
PubMed: 38768145
DOI: 10.1371/journal.pone.0301688 -
Pharmacological Research Jun 2024Studies have shown that the microbiota-gut-brain axis is highly correlated with the pathogenesis of depression in humans. However, whether independent oral microbiome...
Studies have shown that the microbiota-gut-brain axis is highly correlated with the pathogenesis of depression in humans. However, whether independent oral microbiome that do not depend on gut microbes could affect the progression of depression in human beings remains unclear, neither does the presence and underlying mechanisms of the microbiota-oral-brain axis in the development of the condition. Hence this study that encompasses clinical and animal experiments aims at investigating the correlation between oral microbiota and the onset of depression via mediating the microbiota-oral-brain axis. We compared the oral microbial compositions and metabolomes of 87 patients with depressive symptoms versus 70 healthy controls. We found that the oral microbial and metabolic signatures were significantly different between the two groups. Significantly, germ-free (GF) mice transplanted with saliva from mice exposing to chronic restraint stress (CRS) displayed depression-like behavior and oral microbial dysbiosis. This was characterized by a significant differential abundance of bacterial species, including the enrichment of Pseudomonas, Pasteurellaceae, and Muribacter, as well as the depletion of Streptococcus. Metabolomic analysis showed the alternation of metabolites in the plasma of CRS-exposed GF mice, especially Eicosapentaenoic Acid. Furthermore, oral and gut barrier dysfunction caused by CRS-induced oral microbiota dysbiosis may be associated with increased blood-brain barrier permeability. Pseudomonas aeruginosa supplementation exacerbated depression-like behavior, while Eicosapentaenoic Acid treatment conferred protection against depression-like states in mice. These results suggest that oral microbiome and metabolic function dysbiosis may be relevant to the pathogenesis and pathophysiology of depression. The proposed microbiota-oral-brain axis provides a new way and targets for us to study the pathogenesis of depression.
Topics: Animals; Dysbiosis; Depression; Male; Humans; Stress, Psychological; Female; Adult; Mice; Restraint, Physical; Mice, Inbred C57BL; Gastrointestinal Microbiome; Brain-Gut Axis; Mouth; Middle Aged; Saliva; Behavior, Animal; Blood-Brain Barrier
PubMed: 38763328
DOI: 10.1016/j.phrs.2024.107214 -
Microbial Pathogenesis Jul 2024Mannheimiahaemolytica is an opportunistic agent of the respiratory tract of bovines, a member of the Pasteurellaceae family, and the causal agent of fibrinous...
Mannheimiahaemolytica is an opportunistic agent of the respiratory tract of bovines, a member of the Pasteurellaceae family, and the causal agent of fibrinous pleuropneumonia. This bacterium possesses different virulence factors, allowing it to colonize and infect its host. The present work describes the isolation and characterization of a serine protease secreted by M. haemolytica serotype 1. This protease was isolated from M. haemolytica cultured media by precipitation with 50 % methanol and ion exchange chromatography on DEAE-cellulose. It is a 70-kDa protease able to degrade sheep and bovine fibrinogen or porcine gelatin but not bovine IgG, hemoglobin, or casein. Mass spectrometric analysis indicates its identity with protease IV of M. haemolytica. The proteolytic activity was active between pH 5 and 9, with an optimal pH of 8. It was stable at 50 °C for 10 min but inactivated at 60 °C. The sera of bovines with chronic or acute pneumonia recognized this protease. Still, it showed no cross-reactivity with rabbit hyperimmune serum against the secreted metalloprotease from Actinobacilluspleuropneumoniae, another member of the Pasteurellaceae family. M. haemolytica secreted proteases could contribute to the pathogenesis of this bacterium through fibrinogen degradation, a characteristic of this fibrinous pleuropneumonia.
Topics: Animals; Mannheimia haemolytica; Sheep; Cattle; Fibrinogen; Hydrogen-Ion Concentration; Serine Proteases; Temperature; Proteolysis; Molecular Weight; Gelatin; Enzyme Stability; Bacterial Proteins; Mass Spectrometry; Chromatography, Ion Exchange; Swine; Virulence Factors
PubMed: 38763316
DOI: 10.1016/j.micpath.2024.106706 -
Journal of Comparative Pathology May 2024Reports of primary cardiovascular disease in goats are rare and most commonly include ventricular septal defect, valvular endocarditis, traumatic pericarditis, ionophore...
Reports of primary cardiovascular disease in goats are rare and most commonly include ventricular septal defect, valvular endocarditis, traumatic pericarditis, ionophore poisoning and nutritional cardiomyopathies. We now report the pathological findings in a 67 kg, 6-year-old, adult female Boer goat that presented with neurological signs (ie, head pressing, unsteadiness and paddling) and hyperthermia 2 days prior to death. Lack of therapeutic response to meloxicam and penicillin‒streptomycin and poor prognosis led to euthanasia of the animal. At necropsy, the main findings included severe aortic dissection with luminal thrombosis and stenosis, and pulmonary congestion and oedema. Histological examination of the aorta revealed severe chronic granulomatous and fibrosing dissecting aortitis with mineralization. Bacterial culture of the affected aortic segment resulted in isolation of a profuse growth of Pasteurella multocida and a moderate growth of Staphylococcus spp. Histopathological findings in the central nervous system were consistent with neurolisteriosis.
Topics: Animals; Pasteurella multocida; Goats; Goat Diseases; Pasteurella Infections; Female; Staphylococcal Infections; Aortic Dissection
PubMed: 38759507
DOI: 10.1016/j.jcpa.2024.04.002 -
BMC Veterinary Research May 2024Actinobacillus pleuropneumoniae (APP) causes porcine pleuropneumonia (PCP), which is clinically characterized by acute hemorrhagic, necrotizing pneumonia, and chronic...
Actinobacillus pleuropneumoniae (APP) causes porcine pleuropneumonia (PCP), which is clinically characterized by acute hemorrhagic, necrotizing pneumonia, and chronic fibrinous pneumonia. Although many measures have been taken to prevent the disease, prevention and control of the disease are becoming increasingly difficult due to the abundance of APP sera, weak vaccine cross-protection, and increasing antibiotic resistance in APP. Therefore, there is an urgent need to develop novel drugs against APP infection to prevent the spread of APP. Naringin (NAR) has been reported to have an excellent therapeutic effect on pulmonary diseases, but its therapeutic effect on lung injury caused by APP is not apparent. Our research has shown that NAR was able to alleviate APP-induced weight loss and quantity of food taken and reduce the number of WBCs and NEs in peripheral blood in mice; pathological tissue sections showed that NAR was able to prevent and control APP-induced pathological lung injury effectively; based on the establishment of an in vivo/in vitro model of APP inflammation, it was found that NAR was able to play an anti-inflammatory role through inhibiting the MAPK/NF-κB signaling pathway and exerting anti-inflammatory effects; additionally, NAR activating the Nrf2 signalling pathway, increasing the secretion of antioxidant enzymes Nqo1, CAT, and SOD1, inhibiting the secretion of oxidative damage factors NOS2 and COX2, and enhancing the antioxidant stress ability, thus playing an antioxidant role. In summary, NAR can relieve severe lung injury caused by APP by reducing excessive inflammatory response and improving antioxidant capacity.
Topics: Animals; Actinobacillus pleuropneumoniae; Flavanones; Acute Lung Injury; NF-E2-Related Factor 2; Actinobacillus Infections; Mice; NF-kappa B; Kelch-Like ECH-Associated Protein 1; Signal Transduction; Female; Membrane Proteins; Heme Oxygenase-1
PubMed: 38755662
DOI: 10.1186/s12917-024-04055-2 -
Journal of Microbiological Methods Jul 2024Bacterial meningitis is an acute infection which requires rapid diagnosis and treatment due to the high mortality and serious consequences of the disease. The purpose of...
Bacterial meningitis is an acute infection which requires rapid diagnosis and treatment due to the high mortality and serious consequences of the disease. The purpose of this study was to design a homemade multiplex PCR and a novel fluorescence biosensor on chip (FBC) to detect three important agents of meningitis including Streptococcus pneumoniae (S. pneumoniae), Neisseria meningitidis (N. meningitidis), and Haemophilus influenzae (H. influenzae). The homemade multiplex PCR can diagnose three bacterial species simultaneously. Fabrication of FBC was carried out based on the deposition of lead nanoparticles on a quartz slide using the thermal evaporation method. Then, the SH-Cap Probe/Target ssDNA /FAM-Rep probe was loaded on lead film. The evaluation of the fluorescence reaction when the probes bind to the target ssDNA was assessed by a Cytation 5 Cell Imaging Multimode Reader Bio-Tek. The limit of detections (LOD) in homemade PCR and FBC to identify S. pneumoniae were 119 × 10 CFU/mL (0.27 ng/μL) and 380 CFU/mL (9 pg/μL), respectively. The LODs of homemade PCR and FBC for detection of N. meningitidis were 4.49 CFU/mL (1.1 pg/μL) and 13 × 10 CFU/mL (30 pg/μL), respectively. Our results confirmed the LODs of homemade PCR and FBC in detection of H. influenzae were 15.1 CFU/mL (30 fg/μL) and 41 × 10 CFU/mL (90 pg/ μL), respectively. Both techniques had appropriate sensitivity and specificity in detection of S. pneumoniae, N. meningitidis and H. influenzae.
Topics: Neisseria meningitidis; Biosensing Techniques; Streptococcus pneumoniae; Haemophilus influenzae; Humans; Multiplex Polymerase Chain Reaction; Meningitis, Bacterial; Limit of Detection; DNA, Bacterial; Sensitivity and Specificity
PubMed: 38754480
DOI: 10.1016/j.mimet.2024.106954