A Comparison Of Fecal Glucocorticoid Metabolite Concentration And Gut Microbiota Diversity In Bonobos (Pan paniscus)

Host sex, age, diet, stress, and social environment have all been found to influence the gut microbiota. In non-human primates (NHP), recent evidence from gorillas found fecal glucocorticoid metabolite concentration (FGMC) had no significant role in structuring their gut microbiota, but there was a significant differential abundance between family Anaerolineaceae and gorilla FGMC. This pattern has yet to be examined in other NHP, like bonobos (Pan paniscus). We compared FGMC to 16S rRNA amplicons for 201 bonobo fecal samples collected in the wild across five months to evaluate the impact of stress, measured with FGMC, on the gut microbiota. Simpsons index was the only alpha diversity index to have a significant linear relationship with FGMC [R2 = 0.9643, F(4, 210) = 28.56, p = 0.0023]. FGMC level explained 1.63% of the variation in beta diversity for Jensen-Shannon Distance, 2.49% for Weighted UniFrac, and 3.53% for Unweighted UniFrac using PERMANOVAs. Differential abundance models showed seventeen taxa that were significantly correlated with FGMC. We found that genus SHD-231 in the family Anaerolinaceae was significant in our differential abundance model results, similar to western lowland gorilla abundance model results. These results suggest bonobos exhibit different patterns than gorillas in alpha and beta diversity measures and that members of the family Anaerolinaceae may be differentially affected by host stress across great apes. Incorporating FGMC into gut microbiota research can provide a more robust understanding of how stress impacts the gut microbiota of primates and humans and has important ties to overall host health.

Metabarcoding in two isolated populations of wild roe deer (Capreolus capreolus) reveals variation in gastrointestinal nematode community composition between regions and among age classes

Background Gastrointestinal nematodes are ubiquitous for both domestic and wild ungulates and have varying consequences for health and fitness. They exist as complex communities of multiple co-infecting species, and we have a limited understanding of how these communities vary in different hosts, regions and circumstances or of how this affects their impacts. Methods We have undertaken ITS2 rDNA nemabiome metabarcoding with next-generation sequencing on populations of nematode larvae isolated from 149 fecal samples of roe deer of different sex and age classes in the two isolated populations of Chizé and Trois Fontaines in France not co-grazing with any domestic ungulate species. Results We identified 100 amplified sequence variants (ASVs) that were assigned to 14 gastrointestinal nematode taxa overall at either genus (29%) or species (71%) level. These taxa were dominated by parasites classically found in cervids—e.g. Ostertagia leptospicularis, Spiculopteragia spp. Higher parasite species diversity was present in the Trois Fontaines population than in the Chizé population including the presence of species more typically seen in domestic livestock (Haemonchus contortus, Bunostomum sp., Cooperia punctata, Teladorsagia circumcincta). No differences in parasite species diversity or community composition were seen in the samples collected from three zones of differing habitat quality within the Chizé study area. Young roe deer hosted the highest diversity of gastrointestinal nematodes, with more pronounced effects of age apparent in Trois Fontaines. The effect of host age differed between gastrointestinal nematode species, e.g. there was little effect on O. leptospicularis but a large effect on Trichostrongylus spp. No effect of host sex was detected in either site. Conclusions The presence of some livestock parasite species in the Trois Fontaines roe deer population was unexpected given the isolation of this population away from grazing domestic livestock since decades. Overall, our results illustrate the influence of host traits and the local environment on roe deer nemabiome and demonstrate the power of the nemabiome metabarcoding approach to elucidate the composition of gastrointestinal nematode communities in wildlife. Graphical Abstract

Gut microbiota develop towards an adult profile in a sex-specific manner during puberty

Accumulating evidence indicates that gut microbiota may regulate sex-hormone levels in the host, with effects on reproductive health. Very little is known about the development of intestinal microbiota during puberty in humans. To assess the connection between pubertal timing and fecal microbiota, and to assess how fecal microbiota develop during puberty in comparison with adult microbiota, we utilized a Finnish allergy-prevention-trial cohort (Flora). Data collected at 13-year follow-up were compared with adult data from a different Finnish cohort. Among the 13-year-old participants we collected questionnaire information, growth data from school-health-system records and fecal samples from 148 participants. Reference adult fecal samples were received from the Health and Early Life Microbiota (HELMi) cohort (n = 840). Fecal microbiota were analyzed using 16S rRNA gene amplicon sequencing; the data were correlated with pubertal timing and compared with data on adult microbiota. Probiotic intervention in the allergy-prevention-trial cohort was considered as a confounding factor only. The main outcome was composition of the microbiota in relation to pubertal timing (time to/from peak growth velocity) in both sexes separately, and similarity to adult microbiota. In girls, fecal microbiota became more adult-like with pubertal progression (p = 0.009). No such development was observed in boys (p = 0.9). Both sexes showed a trend towards increasing relative abundance of estrogen-metabolizing Clostridia and decreasing Bacteroidia with pubertal development, but this was statistically significant in girls only (p = 0.03). In girls, pubertal timing was associated positively with exposure to cephalosporins prior to the age of 10. Our data support the hypothesis that gut microbiota, particularly members of Ruminococcaceae, may affect pubertal timing, possibly via regulating host sex-hormone levels.Trial registration The registration number for the allergy-prevention-trial cohort: ClinicalTrials.gov, NCT00298337, registered 1 March 2006—Retrospectively registered, https://clinicaltrials.gov/show/NCT00298337. The adult-comparison cohort (HELMi) is NCT03996304.

Diet-driven mercury contamination is associated with polar bear gut microbiota

The gut microbiota may modulate the disposition and toxicity of environmental contaminants within a host but, conversely, contaminants may also impact gut bacteria. Such contaminant-gut microbial connections, which could lead to alteration of host health, remain poorly known and are rarely studied in free-ranging wildlife. The polar bear (Ursus maritimus) is a long-lived, wide-ranging apex predator that feeds on a variety of high trophic position seal and cetacean species and, as such, is exposed to among the highest levels of biomagnifying contaminants of all Arctic species. Here, we investigate associations between mercury (THg; a key Arctic contaminant), diet, and the diversity and composition of the gut microbiota of polar bears inhabiting the southern Beaufort Sea, while accounting for host sex, age class and body condition. Bacterial diversity was negatively associated with seal consumption and mercury, a pattern seen for both Shannon and Inverse Simpson alpha diversity indices (adjusted R2 = 0.35, F1,18 = 8.00, P = 0.013 and adjusted R2 = 0.26, F1,18 = 6.04, P = 0.027, respectively). No association was found with sex, age class or body condition of polar bears. Bacteria known to either be involved in THg methylation or considered to be highly contaminant resistant, including Lactobacillales, Bacillales and Aeromonadales, were significantly more abundant in individuals that had higher THg concentrations. Conversely, individuals with higher THg concentrations showed a significantly lower abundance of Bacteroidales, a bacterial order that typically plays an important role in supporting host immune function by stimulating intraepithelial lymphocytes within the epithelial barrier. These associations between diet-acquired mercury and microbiota illustrate a potentially overlooked outcome of mercury accumulation in polar bears.

Recurrent evolution of cross-resistance in response to selection for improved post-infection survival in Drosophila melanogaster

The host susceptibility to one pathogen can decrease, increase, or remain unaffected by virtue of the host evolving resistance towards a second pathogen. Negative correlations between a host susceptibility to different pathogens is an often-cited explanation for maintenance of genetic variation in immune function determining traits in a host population. In this study, we investigated the change in susceptibility of Drosophila melanogaster flies to various novel bacterial pathogens after being experimentally selected for increased resistance to one particular bacterial pathogen. We independently selected flies to become more resistant towards Enterococcus faecalis and Pseudomonas entomophila, and baring a few exceptions the evolved populations exhibited cross-resistance against the range of pathogens tested in the study. Neither the identity of the native pathogen nor the host sex was major determining factors in predicting the pattern of cross-resistance exhibited by the selected populations. We therefore report that a generalized cross-resistance to novel pathogens can repeatedly evolve in response to selection for resistance against a single pathogen.

Epidemiological associations with genomic variation in SARS-CoV-2

SARS-CoV-2 (CoV) is the etiological agent of the COVID-19 pandemic and evolves to evade both host immune systems and intervention strategies. We divided the CoV genome into 29 constituent regions and applied novel analytical approaches to identify associations between CoV genomic features and epidemiological metadata. Our results show that nonstructural protein 3 (nsp3) and Spike protein (S) have the highest variation and greatest correlation with the viral whole-genome variation. S protein variation is correlated with nsp3, nsp6, and 3′-to-5′ exonuclease variation. Country of origin and time since the start of the pandemic were the most influential metadata associated with genomic variation, while host sex and age were the least influential. We define a novel statistic—coherence—and show its utility in identifying geographic regions (populations) with unusually high (many new variants) or low (isolated) viral phylogenetic diversity. Interestingly, at both global and regional scales, we identify geographic locations with high coherence neighboring regions of low coherence; this emphasizes the utility of this metric to inform public health measures for disease spread. Our results provide a direction to prioritize genes associated with outcome predictors (e.g., health, therapeutic, and vaccine outcomes) and to improve DNA tests for predicting disease status.

Host Sex Steroids Interact With Virus Infection: New Insights Into Sex Disparity in Infectious Diseases

Sex hormones are steroid hormones synthesized from the gonads of animals and tissues such as the placenta and adrenocortical reticular zone. The physiological functions of sex hormones are complex. Sex hormones are not only pathologically correlated with many diseases of the reproductive system, but are etiological factors in some viral infectious diseases, including disease caused by infections of coronaviruses, herpesviruses, hepatitis viruses, and other kinds of human viruses, which either exhibit a male propensity in clinical practice, or crosstalk with androgen receptor (AR)-related pathways in viral pathogenesis. Due to the global pandemic of coronavirus disease 2019 (COVID-19), the role of androgen/AR in viral infectious disease is highlighted again, majorly representing by the recent advances of AR-responsive gene of transmembrane protease/serine subfamily member 2 (TMPRSS2), which proteolytically activates the receptor-mediated virus entry by many coronaviruses and influenza virus, along with the role of androgen-mediated signaling for the transcription of hepatitis B virus (HBV), and the role of sex hormone responsive genes during Zika virus (ZIKV) pathogenesis, et al. Collectively, we propose to provide a comprehensive overview of the role of male sex hormones during multiple phases in the life cycle of different human viruses, which may be partly responsible for the sex-specific prevalence, severity and mortality of some diseases, therefore, may provide clues to develop more efficient prevention and treatment strategies for high-risk populations.

Distribution of Deer Keds (Diptera: Hippoboscidae) in Free-Living Cervids of the Tuscan-Emilian Apennines, Central Italy, and Establishment of the Allochthonous Ectoparasite Lipoptena fortisetosa

Lipoptena fortisetosa and L. cervi are hematophagous ectoparasites belonging to the Hippoboscidae family and preferentially living on cervids. In recent years, they have received specific attention due to the great increase in the abundance of their host species, and to their medical and veterinary importance as possible vectors of pathogens harmful to humans and animals. The aim of this study was to investigate the parasitism level of both of these flies on their main hosts in Italy, which are red deer, fallow deer, and roe deer, and to highlight a possible preference for a species, sex, or age class among the hosts. Deer keds were collected by examining 326 cervids hunted in the Tuscan-Emilian Apennines. Outcomes showed that L. fortisetosa has greatly spread throughout the study area, where it competes with the autochthonous L. cervi. Moreover, red deer was the favored host species of both ectoparasites, while different preferences for host sex and age classes were observed in the two hippoboscids. The regular monitoring of deer ked populations, especially the allochthonous L. fortisetosa, which is continuously spreading in Europe, is recommended to expand the knowledge on these parasitic species that are potentially dangerous to public health.