RÉSUMÉ
Background and Aim: Several strains of Aspergillus fumigatus produce mycotoxins that affect the health and productivity of dairy cattle, and their presence in dairy cattle feed is a serious concern. This study aimed to determine the densities of A. fumigatus and gliotoxin in commercial dairy feed. Materials and Methods: More than 60 dairy feed samples were examined for fungal contamination, specifically for A. fumigatus, using phenotypic approaches and DNA sequencing of the internal transcribed spacer (ITS) and ß-tubulin regions. Thin-layer chromatography and high-performance liquid chromatography (HPLC) were used to assess gliotoxin production in A. fumigatus. Real-time polymerase chain reaction (RT-PCR) was used to investigate the expression of gliZ, which was responsible for gliotoxin production. High-performance liquid chromatography was used to detect gliotoxin in feed samples. Results: Aspergillus was the most commonly identified genus (68.3%). Aspergillus fumigatus was isolated from 18.3% of dairy feed samples. Only four of the 11 A. fumigatus isolates yielded detectable gliotoxins by HPLC. In total, 7/11 (43.7%) feed samples tested had gliotoxin contamination above the threshold known to induce immunosuppressive and apoptotic effects in vitro. The HPLC-based classification of isolates as high, moderate, or non-producers of gliotoxin was confirmed by RT-PCR, and the evaluation of gliZ expression levels corroborated this classification. Conclusion: The identification of A. fumigatus from animal feed greatly depended on ITS and ß-tubulin sequencing. Significant concentrations of gliotoxin were found in dairy cattle feed, and its presence may affect dairy cow productivity and health. Furthermore, workers face contamination risks when handling and storing animal feed.
RÉSUMÉ
AIMS: Asthma affects a large number of people worldwide and is characterized by chronic allergic airway inflammation. Anatabine is a natural alkaloid that is structurally similar to nicotine and found in the Solanaceae family of plants, with anti-inflammatory properties. Consequently, this study aimed to evaluate the potential therapeutic effect of anatabine against asthma. MAIN METHODS: Ovalbumin was used to induce asthma in rats. Two asthmatic groups were treated with low and high doses of anatabine. KEY FINDINGS: Asthmatic animals experienced increased total leukocyte count and inflammatory cytokines in bronchoalveolar lavage fluid (BALF), bronchitis, and bronchopneumonia associated with mast cell infiltration. Additionally, inducible nitric oxide synthase immunostaining was observed, with decreased pulmonary antioxidant capacity and enzymes and decreased Nrf2 and HO-1 gene expression while increased NFκB-P65 expression. Interestingly, asthmatic animals treated with anatabine at both doses showed dose-dependently decreased inflammatory cells and cytokine levels within BALF reduced inflammation in the airways through decreased mast cell infiltration within lung tissues and increased antioxidant enzymes and Nrf2 and Ho-1 expression levels. SIGNIFICANCE: Our results highlight the potential beneficial effect of anatabine against asthma through anti-inflammatory and antioxidant mechanisms. Therefore, anatabine is a promising candidate for pulmonary asthma treatment.
Sujet(s)
Alcaloïdes , Asthme , Alcaloïdes/métabolisme , Alcaloïdes/pharmacologie , Alcaloïdes/usage thérapeutique , Animaux , Anti-inflammatoires , Antioxydants/métabolisme , Asthme/induit chimiquement , Asthme/traitement médicamenteux , Asthme/métabolisme , Liquide de lavage bronchoalvéolaire , Cytokines/métabolisme , Heme oxygenase (decyclizing)/métabolisme , Inflammation/traitement médicamenteux , Inflammation/métabolisme , Poumon/métabolisme , Facteur-2 apparenté à NF-E2/métabolisme , Nicotine/pharmacologie , Nitric oxide synthase type II/métabolisme , Ovalbumine , Stress oxydatif , Pyridines , Rats , Régulation positiveRÉSUMÉ
Canine vector-borne pathogens are a group of widespread microorganisms and nematodes transmitted by arthropods that do not only impact dog health but may also pose a health risk to humans as many of them are zoonotic. As no data exist on the presence of canine vector-borne pathogens in Kosovo, we here present a first study on the seroprevalence of selected vector-borne pathogens, the dog heartworm Dirofilaria immitis and the bacteria Anaplasma spp., Ehrlichia spp. and Borrelia burgdorferi sensu lato. The study was carried out from July to October 2019 in all regions of Kosovo and included 149 clinically healthy dogs (84 owned, 40 sheltered and 25 free-ranging). Blood samples collected from each individual were tested using a commercially available rapid multiplex enzyme-linked immunosorbent assay. In total, 37.6% of the examined dogs were seropositive for one or more of the target pathogens. Most frequently, antibodies were found against Anaplasma spp. (24.8% of the dogs tested), followed by antigen detection of D. immitis (14.8%) and antibodies of B. burgdorferi s.l. (1.3%). The lowest antibody prevalence (0.7%) showed E. canis where only one dog was found positive. This preliminary study demonstrates the circulation of several zoonotic vector-borne pathogens in natural cycles involving dogs in Kosovo. It should trigger studies on infection prevalences in humans and initiate vector surveillance programmes in order to manage and control transmission and the diseases associated with the pathogens.