Entomopathogenic fungi routinely kill their hosts before releasing infectious spores, but a few species keep insects alive while sporulating, which enhances dispersal. Transcriptomics- and metabolomics-based studies of entomopathogens with post-mortem dissemination from their parasitized hosts have unraveled infection processes and host responses. However, the mechanisms underlying active spore transmission by Entomophthoralean fungi in living insects remain elusive. Here we report the discovery, through metabolomics, of the plant-associated amphetamine, cathinone, in four Massospora cicadina -infected periodical cicada populations, and the mushroom-associated tryptamine, psilocybin, in annual cicadas infected with Massospora platypediae or Massospora levispora , which likely represent a single fungal species. The absence of some fungal enzymes necessary for cathinone and psilocybin biosynthesis along with the inability to detect intermediate metabolites or gene orthologs are consistent with possibly novel biosynthesis pathways in Massospora . The neurogenic activities of these compounds suggest the extended phenotype of Massospora that modifies cicada behavior to maximize dissemination is chemically-induced.

Brachycybe (Wood) is a genus of fungivorous millipedes. To date, the fungal associates of these millipedes have never been characterized. In an attempt to resolve these relationships, culture-based approaches combined with DNA barcode sequencing were used. Sampling of 313 individuals collected from three of four B. lecontii clades and 20 sites across seven states uncovered at least 183 genera in 40 orders from four fungal phyla. At least seven putative new species were recovered in this study, despite the use of more classical culture-based approaches. Three of these fungi were phylogenetically resolved using ITS + LSU and include two new species, aff. Fonsecaea sp., Mortierella aff. ambigua, and a new genus related to Apophysomyces. Overall, the results of this study highlight the vast amount of undescribed fungal biodiversity associated with millipedes. Twelve fungal genera from nine orders showed high connectivity across the entire B. lecontii-associated fungal network, indicating a central role for these fungi in their association with these millipedes. These twelve include the two putative new species described above. The ecology of these and other fungal associates were also explored, using fungal cohort pairings and entomopathogenicity trials. Over 40% of all fungal pairings resulted in competitive interactions, a majority of which involved inhibition or overgrowth by fungi in the Hypocreales and Polyporales, respectively. The abundance of these competitive interactions in these two orders indicate differing ecological strategies. Hypocreales used chemical warfare to competitively exclude other fungi, while Polyporales physically overgrew their competitors. Mucoromycotan fungi used a similar strategy to the Polyporales. Results of a series of entomopathogenicity trials indicated that B. lecontii was less susceptible to entomopathogenic Hypocreales than an insect model (Galleria mellonella), even though these fungi are known to attack several classes of arthropods. Furthermore, the absence of a negative interaction between B. lecontii and entomopathogenic Hypocreales may indicate a beneficial relationship. When challenged with Polyporales, B. lecontii exhibited high mortality, while G. mellonella was unaffected. This stands in sharp contrast to previous casual observations of the feeding behavior of B. lecontii. Recent discoveries of previously overlooked fungal diversity have been groundbreaking and hint at substantial cryptic fungal biodiversity across the globe. The 200-300 million-year-old association between fungi and the Colobognatha, which includes Brachycybe lecontii, provides an ideal system to uncover biodiversity and examine function of these fungi in a highly understudied and ancient association.

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Entomopathogenic fungi routinely kill their hosts before releasing infectious spores, but select species keep insects alive while sporulating, which enhances dispersal. Transcriptomics and metabolomics studies of entomopathogens with post-mortem dissemination from their parasitized hosts have unraveled infection processes and host responses, yet mechanisms underlying active spore transmission by Entomophthoralean fungi in living insects remain elusive. Here we report the discovery, through metabolomics, of the plant-associated amphetamine, cathinone, in four Massospora cicadina-infected periodical cicada populations, and the mushroom-associated tryptamine, psilocybin, in annual cicadas infected with Massospora platypediae or Massospora levispora, which appear to represent a single fungal species. The absence of some fungal enzymes necessary for cathinone and psilocybin biosynthesis along with the inability to detect intermediate metabolites or gene orthologs are consistent with possibly novel biosynthesis pathways in Massospora. The neurogenic activities of these compounds suggest the extended phenotype of Massospora that modifies cicada behavior to maximize dissemination is chemically-induced.

The objective of the current study was to determine if age, diet, and genetic disposition (animal strain) in an animal model had early effects on specific molecular markers in circulating peripheral blood mononuclear cells (PBMCs). Three strains [Sprague-Dawley (SD), Fischer 344 (F344), and Brown-Norway (BN)] of male rats were maintained on a high-fat (HF) or regular diet. Blood was collected at 4, 12, and 24 wk to assess chemistry and to recover PBMCs. Triglycerides and body weight gain increased at all time points in the HF diet group for each strain. Telomere length in PBMCs decreased in the HF diet group compared to the regular diet group up to 24 wk in all strains. Telomere length decreased in PBMCs at 24 wk compared to baseline in all strains, indicating an age-related effect. These findings highlight that diet and age cause changes in PBMCs recovered from different strains of rats. The next tier of studies will examine the contribution of an occupational exposure (e.g., welding fume inhalation) in combination with diet, age, and strain, to assess changes in the molecular responses of isolated PBMCs. In addition, studies involving lifestyle exposure (e.g., tobacco smoke) are in the planning stages and will assess the long-term effects of exposure in our animal model.

The goal of this study was to use liquid chromatography mass spectrometry to assess metabolic changes of two different diets in three distinct rat strains. Sprague-Dawley, Fischer 344, and Brown-Norway male rats were maintained on a high-fat, or regular diet for 24 weeks. Liver tissue was collected at 4, 12, and 24 weeks to assess global small molecule metabolite changes using high resolution accurate mass spectrometry coupled to ultrahigh-performance liquid chromatography. The results of the global metabolomics analysis revealed significant changes based on both age and diet within all three strains. Principal component analysis revealed that the influence of diet caused a greater variation in significantly changing metabolites than that of age for the Brown Norway and Fisher 344 strains, whereas diet had the greatest influence in the Sprague Dawley strain only at the 4-week time point. As expected, metabolites involved in lipid metabolism were changed in the animals maintained on a high fat diet compared to the regular diet. There were also significant changes observed in the concentration of Tri carboxylic acid cycle intermediates that were extracted from the liver of all three strains based on diet. The results of this study showed that a high fat diet caused significant liver and metabolic changes compared to a regular diet in multiple rat strains. The inbred Fisher 344 and Brown Norway rats were more metabolically sensitive to the diet changes than outbred Sprague Dawley strain. The study also showed that age, as was the case for Sprague Dawley, is an important variable to consider when assessing metabolic changes.

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It is estimated that greater than 1 million workers are exposed to welding fume (WF) by inhalation daily. The potentially toxic metals found in WF are known to cause multiple adverse pulmonary and systemic effects, including cardiovascular disease, and these metals have also been shown to translocate to the liver. This occupational exposure combined with a high fat (HF) Western diet, which has been shown to cause hyperlipidemia and non-alcoholic fatty liver disease (NAFLD), has the potential to cause significant mixed exposure metabolic changes in the liver. The goal of this study was to use matrix assisted laser desorption ionization imaging mass spectrometry (MALDI-IMS) to analyze the spatial distribution and abundance changes of lipid species in Sprague Dawley rat liver maintained on a HF diet combined with WF inhalation. The results of the MALDI-IMS analysis revealed unique hepatic lipid profiles for each treatment group. The HF diet group had significantly increased abundance of triglycerides and phosphatidylinositol lipids, as well as decreased lysophosphatidic lipids and cardiolipin. Ceramide-1-phosphate was found at higher abundance in the regular (REG) diet WF-exposed group which has been shown to regulate the eicosanoid pathway involved in pro-inflammatory response. The results of this study showed that the combined effects of WF inhalation and a HF diet significantly altered the hepatic lipidome. Additionally, pulmonary exposure to WF alone increased lipid markers of inflammation.