Toxic thermoresistant metabolites of Fusarium oxysporum are capable of inducing histopathological alterations in Wistar rats

Abstract

Abstract:The genus Fusarium is known to produce mycotoxins that cause fusariosis in plants, animals and humans. Mycotoxins are among the virulence factors of this genus. Metabolic extracts of Fusarium oxysporum, isolated from a patient with onychomycosis and sterilized by filtration or autoclave, were inoculated intradermally into Wistar rats at concentrations of 0.25, 0.5 and 1 μg/μL, and the effects on their tegument were observed at 24 and 72 hours. After histological procedures and staining by hematoxylineosin, the sections were studied for their inflammatory-reaction intensity and for evidence of injury and tissue distortion. Inflammatory reactions in the dermis and the subcutaneous tissue were observed at all concentrations of the inoculated extract tested. There was a significant influx of neutrophils, mastocytes and lymphocytes, as well as a large quantity of macrophages. Apoptotic bodies and hyperemic blood vessels were observed. This reaction was directly related to the extract concentration, and was most intense in animals that received the 1 mg/µL dose. The maximum peak was observed at 24 hours. The autoclaved metabolic extract produced the same effects as the untreated one, indicating the presence of heat-resistant metabolites. In conclusion, the metabolic extracts obtained from sterilized culture filtrates of F. oxysporum are capable of inducing an inflammatory response within 24 hours in the dermis and subcutaneous tissue of rats.

Toxic, but beneficial compounds from endophytic fungi of Carica papaya

“…as the most prevalent species and a potent source of biologically active compounds (37,38). Many studies have been carried out on metabolites production from several Fusarium species especially F. oxysporum and F. solani (39)(40)(41)(42). Fusarium equiseti (Nectriaceae) (teleomorph: Gibberella intricans) is a toxigenic species and a soil inhabitant known to cause disease in several plant species.…”

First report of Fusarium oxysporum species complex infection in zebrafish culturing system

“…Experience of disease outbreaks in zebrafish facility is very critical when considering the precise results from the experiments, operational cost and public health (diseases transmissible to researchers), etc. More importantly, confounding effects of unknown infections or stressors in experimental mammals reportedly changed the research outcome of histology, gene regulation, physiology and immunology (Gentry & Cooper 1981;Hernandes et al 2012). Therefore, identifications of new pathogens in zebrafish systems and knowledge of factors associated with pathogenicity, growth regulatory and inhibitory factors are benefited to overall zebrafish community by improving the fish health and reduction of unwanted variability to further development of the zebrafish as a versatile model organism.…”

Are metabolites of Fusarium oxysporum responsible for fungal skin invasion? A morphological and Raman spectroscopy monitoring

“…However, it should be noted that during dialysis to obtain the crude extract, molecules with a weight below 12–16 KDa, such as the trichothecenes, (250–500 Da), which are known to cause tissue reaction, whether in the form of inflammation or induction of programmed cell death, were also eliminated. Additionally, some molecules may have been damaged when obtaining the fraction, when the crude extract was heated to approximately 40 °C in a rotaevaporator . The results of TUNEL staining reinforce this hypothesis, as there was no TUNEL‐positive staining in the skin injected with the fraction.…”

“…Additionally, some molecules may have been damaged when obtaining the fraction, when the crude extract was heated to approximately 40°C in a rotaevaporator. [17] The results of TUNEL staining reinforce this hypothesis, as there was no TUNEL-positive staining in the skin injected with the fraction. Contrastingly, topically treated skin [18] or skin injected with the crude extract had staining in the epidermis, dermis, and even the subcutaneous tissue.…”