Metarhizium spp. have emerged as an alternative to chemical pesticides for protecting crops from insect pest. Here, we investigated midgut microbial community and metabolites of Spodoptera litura at three different timepoints after infection with Metarhizium flavoviride. The innate immune system of S. litura was activated with levels of polyphenol oxidase, carboxylesterase, multifunctional oxidase, and glutathione S-transferase activity significantly increasing. Exposure to the fungal pathogen also altered bacterial abundance and diversity in host\'s midgut, and these changes varied depending on the time elapsed since exposure. We identified more operational taxonomic units in the treated samples as compared to the control samples at all tested time points. A total of 372 metabolites were identified, and 88, 149, and 142 differentially accumulated metabolites (DAMs) were identified between the treatment and control groups at 3 timepoints after treatment, respectively. Based on the changes of DAMs in response to M. flavoviride infection at different timepoints and significantly enriched KEGG pathways, we speculated that \"tyrosine metabolism,\" \"galactose metabolism,\" \"ATP-binding cassette transporters,\" \"neuroactive ligand-receptor interaction,\" \"purine metabolism,\" \"arginine and proline metabolism,\" \"beta-alanine metabolism,\" \"lysosome,\" and \"carbon metabolism\" may participate in the metabolic-level defense response. An integrated pathway-level analysis of the 16S-rDNA and metabolomic data illustrated the connections and interdependencies between the metabolic responses of S. litura and the midgut microorganisms to M. flavoviride infection. This work emphasizes the value of integrated analyses of insect-pathogen interactions, provides a framework for future studies of critical microorganisms and metabolic determinants of these interactions, establishes a theoretical basis for the sustainable use of M. flavoviride.

Men with prediabetes often exhibit concomitant low-quality sperm production or even infertility, problems which urgently require improved therapeutic options. In this study, we have established a sheep model of diet-induced prediabetes that is associated with spermatogenic defects and have explored the possible underlying metabolic causes.
We compared male sheep fed a normal diet with those in which prediabetes was induced by a rich diet and with a third group in which the rich diet was supplemented by melatonin. Only the rich diet group had symptoms of prediabetes, and in these sheep, we found impaired spermatogenesis characterized by a block in the development of round spermatids and an increased quantity of testicular apoptotic cells. Comparing the gut microbiomes and intestinal digest metabolomes of the three groups revealed a distinctive difference in the taxonomic composition of the microbiota in prediabetic sheep, and an altered metabolome, whose most significant feature was altered sphingosine metabolism; elevated sphingosine was also found in blood and testes. Administration of melatonin alleviated the symptoms of prediabetes, including those of impaired spermatogenesis, while restoring a more normal microbiota and metabolic levels of sphingosine. Fecal microbiota transplantation from prediabetic sheep induced elevated sphingosine levels and impaired spermatogenesis in recipient mice, indicating a causal role of gut microbiota in these phenotypes.
Our results point to a key role of sphingosine in the disruption of spermatogenesis in prediabetic sheep and suggest it could be a useful disease marker; furthermore, melatonin represents a potential prebiotic agent for the treatment of male infertility caused by prediabetes.

BACKGROUND: Although there are many hypotheses, the pathogenesis of Crohn\'s disease (CD) is not completely clear so far. Exclusive enteral nutrition (EEN) is a routine measure in the treatment of active CD. We aimed at investigating the impact of EEN on patients with active CD from microbial metabolomics.
METHODS: 16S-rDNA sequencing technology and gas chromatography-mass spectrometer analysis were employed to investigate the modification of the intestinal flora and fecal short-chain fatty acid (SCFA) during the EEN.
RESULTS: Seven patients with CD, who conducted EEN, were followed up successfully in the present study. The 8-week EEN resulted in a remission of the condition of subjects with active CD, as revealed by a significant decrease in erythrocyte sedimentation rate (ESR) (P = 0.018), C-reactive protein (CRP) (P = 0.028), and Crohn\'s disease activity index (CDAI) (P = 0.018). The nutrition of the subjects was improved after an 8-week treatment course with EEN, which was associated with an increase in body mess index (BMI) (P = 0.018) and serum albumin (ALB) (P = 0.018) levels. Furthermore, our investigations revealed a significantly increased abundance of Firmicutes paralleled by decreased levels of Proteobacteria. With respect to the genus, five species of bacteria including Ruminococcus (P = 0.01), Lachnospiraceae (P = 0.02), Anaerotruncus (P = 0.04), Flavonifractor (P = 0.04), and Novosphingobium (P = 0.05) showed significantly increased abundance. This was accompanied by relative changes in fecal short-chain fatty acids levels. Moreover, we successfully constructed a stable model by combining these five significantly different genera to predict the therapeutic effect of EEN on patients with CD (AUC = 0.9598).
CONCLUSIONS: The findings indicated that EEN can alleviate the condition and the nutrition of patients with active CD by regulating the intestinal flora and influencing the expression level of fecal short-chain fatty acids.

OBJECTIVE: This study aimed to explore the effects of Psidium guajava L. extracts on mice diarrhea model and changes in their intestinal microflora diversity.
METHODS: Mice diarrhea model was constructed with Folium Sennae. and The therapeutic effects of Psidium guajava L. extracts on diarrhea were evaluated by loose stools rates, diarrhea rates, diarrhea index and motor functions of intestine.
RESULTS: Our results showed that all three kinds of extracts from Psidium guajava L. had inhibitory effects on Folium Sennae -induced diarrhea model. The proportion of Bacteroidetes is lower in Group DF (diarrhea model group) compared with Group B (blank group), while abundance of Deferribacteraceae was found in Group DF. The proportion of Deferribacteraceae lowered in Group DTF (diarrhea treatment group) treated with extracts from Psidium guajava L.
CONCLUSIONS: However, mechanisms underlying the therapeutic effect of Psidium guajava L. and the changes in intestinal microflora still await further exploration.