Gut eubiosis is essential for the host’s health. In athletes, the gut microbiota can be altered by several factors, including diets. While eubiotic gut microbiota in elite rugby players has been reported, our survey found that university rugby players suffered from loose stools and frequent urgency to defecate. To establish the causes of the condition, the microbiota and the concentrations of organic acids in fecal samples of university male rugby players (URP) were analyzed and compared with those of age-matching, non-rugby playing males (control). Body mass indices were significantly (p < 0.05) different between groups. Chao1 index was significant (p < 0.05) lower in URP than in control. The relative abundances of phyla Firmicutes and Bacteroidetes were significantly (p < 0.05) higher and lower, respectively, in URP than in control. Potential pathobiont genera Collinsella, Enterobacter, and Haemophilus were significantly (p < 0.05) abundant, whereas beneficial Akkermansia was lower (p < 0.05) in URP than in control. Succinate, a potential causative of gut inflammation, was five-fold higher in URP than in controls. Our findings all but confirmed that the dysbiotic status of gut in URP.

Background Exosomes, which are observed in all human fluid, including serum, are nanosized extracellular vesicles with a mechanism of intercellular communication. Potential clinical applications of exosomes in neonatal diseases have recently been discussed. However, the characteristics of exosomes in serum during early infancy is unclear. Methods In this prospective study, we evaluated the chronological changes in the concentration of serum‐derived exosomes of 20 infants for 12 months after birth. Results The average concentration of serum‐derived exosomes was 4.6 × 1010 particles/mL at birth and increased significantly until the age of 48 weeks. There was a moderate correlation between the gestational age and the concentration of serum‐derived exosomes both at birth (r = 0.54, P = 0.01) and during the 8 weeks after birth (r = 0.48, P < 0.001). A multivariable analysis showed that gestational age at birth was associated with the concentration of serum‐derived exosomes at birth (partial regression coefficient, 0.86; 95% confidence interval, 0.37–1.37; P = 0.002). Conclusions The concentration of serum‐derived exosomes in preterm infants increased both chronologically and by gestational age after birth. These basic data may help to further understand physiology of exosomes in preterm infants.

Background: Exosomes are nanosized extracellular vesicles, that play important roles in intercellular immune regulation. They have potential therapeutic utility for neonatal diseases including necrotizing enterocolitis. Breast-milk-derived exosomes have recently shown beneficial effects on intestinal damage in vitro and in vivo. However, the chronological change in breast-milk-derived exosome concentrations after delivery are unclear. Methods:In this prospective study, we enrolled 17 mothers who delivered premature infants admitted to a neonatal intensive care unit in Japan. We measured the consecutive concentrations of breast-milk-derived exosomes in the mothers for 48 weeks after delivery. Results:The median concentration of breast-milk-derived exosomes was 1.62 × 10 8 particles/ml in colostrum, showing a significant decrease after 2 weeks (P < 0.01).There was no association between the exosome concentration in colostrum and maternal perinatal factors including parity, mode of delivery, maternal age, and gestational age at delivery. Conclusions:We concluded that breast-milk-derived exosomes were the richest in colostrum. Our basic data regarding breast-milk-derived exosomes are expected to aid in the clinical application of exosomes for treating neonatal diseases.