Characteristics of cadence during continuous walking in daily life.

Despite the acknowledged relationship between the usual (preferred) walking speed (UWS) and health, there is currently no practical method available to reliably and accurately detect slight changes in UWS. This study aimed to explore whether either of the following two phenomena occurs during continuous daily walking in various periods: (a) Similarity between the most frequent cadences in the two periods. (b) The occurrence of the most frequent cadence in at least one of the two periods during the other period, with a frequency close to that of the most frequent cadence. In August 2021, invitations to participate in the study were extended via email to participants that took part in the Japan COVID-19 and Society Internet Surveys (JACSIS). A mobile phone application that collected step data during continuous walking was provided to the participants, and data were collected from December 1, 2021, to January 31, 2022. While 1022 participants installed the phone application, only 505 had measurement data for ten days or more in each of the two months of the study duration. The cadence during continuous walking was automatically measured daily from 05:00 to 21:00. Most participants exhibited at least one of the phenomena mentioned above, confirming a common, notably frequent, invariant cadence over time. Overall, this method allows for the identification of minor reductions and lower bounds of decline in UWS. This study illustrates the potential for tracking a decreasing trend in UWS. Early detection of a downward trend permits individuals to take timely remedial action, as recovery is relatively easy, and the confirmation of even a slight recovery bolsters recovery motivation.

Risk of gestational diabetes in women with PCOS based on body mass index: The Japan Environment and Children's Study.

CONTEXT: Women with polycystic ovary syndrome (PCOS), which is the most common endocrine disorder in women of reproductive age, have a potentially increased risk of gestational diabetes mellitus (GDM). OBJECTIVE: To examine the impact of PCOS on GDM based on maternal body mass index (BMI) using data from a large birth cohort study in Japan. DESIGN: Prospective observational study using data from the Japan Environment and Children's Study (JECS). PARTICIPANTS: Singleton pregnancies in the JECS during 2011-2014 were included. Mothers with HbA1c levels of ≥6.5% in the first trimester and history of DM or steroid use during pregnancy were excluded. MAIN OUTCOME MEASURES: Participants were categorized according to their pre-pregnancy BMIs: G1 (<18.5 kg/m2), G2 (18.5-19.99 kg/m2), G3 (20.0-22.99 kg/m2), G4 (23.0-24.99 kg/m2), and G5 (≥25.0 kg/m2). The impact of PCOS on early (Ed) and late-onset (Ld) GDM for each group was estimated using a multiple logistic regression model. RESULTS: We included 92774 participants, comprising 2012 PCOS(+) cases. GDM occurrence was higher in women with PCOS (p<0.001). PCOS had no effect on GDM in G1, G2, and G3. In G4, PCOS increased the risk of Ed GDM (adjusted odds ratio [aOR]: 3.27, 95% confidence interval [CI]: 1.29-8.29). In G5, PCOS increased the risk of both Ed (aOR: 2.48, 95% CI: 1.53-4.02) and Ld GDM (aOR: 1.94, 95% CI: 1.23-3.07). CONCLUSIONS: The impact of PCOS on GDM occurrence depended on the pre-pregnancy BMIs, which may facilitate personalized preconception counseling among women with PCOS.

Prenatal risk factors of indoor environment and incidence of childhood eczema in the Japan Environment and Children's Study.

The quality of indoor environment is a risk factor for early childhood eczema and atopic dermatitis; however, its influence during pregnancy on childhood eczema in Japan has not been investigated. In this study, we aimed to determine the indoor environmental factors that are associated with eczema in children up to 3 years of age, using national birth cohort data from the Japan Environment and Children's Study (JECS). Information on indoor environments and eczema symptoms until 3 years of age was collected using self-administered questionnaires to the mothers. A total of 71,883 and 58,639 mother-child pairs at 1.5- and 3-years-old, respectively, were included in the former analyses. To account for prenatal indoor risk factors, 17,568 (1.5-years-old) and 7063 (3-years-old) children without indoor mold and/or ETS exposure were included in the final analysis. A higher mold index, gas heater use, parquet flooring use, and frequent insecticide use showed significantly increased risks for childhood eczema up to 3 years of age. These associations were consistent after stratification analysis among children whose parents did not have a history of allergies. The updated WHO guidelines on indoor air quality should be implemented based on recent findings regarding the effects of prenatal exposure to indoor dampness on health effects of children further in life, including asthma, respiratory effects, eczema, and other immunological effects.

Association between maternal blood or cord blood metal concentrations and catch-up growth in children born small for gestational age: an analysis by the Japan environment and children's study.

BACKGROUND: Catch-up growth issues among children born small for gestational age (SGA) present a substantial public health challenge. Prenatal exposure to heavy metals can cause adverse effects on birth weight. However, comprehensive studies on the accurate assessment of individual blood concentrations of heavy metals and their effect on the failure to achieve catch-up growth remain unavailable. This study aimed to evaluate the effects of uterine exposure to toxic metals cadmium, lead, and mercury and essential trace metals manganese and selenium at low concentrations on the postnatal growth of children born SGA. METHODS: Data on newborn birth size and other factors were obtained from the medical record transcripts and self-administered questionnaires of participants in the Japan Environment and Children's Study. The blood concentrations of lead, cadmium, mercury, selenium, and manganese in pregnant women in their second or third trimester were determined by inductively coupled plasma mass spectrometry. These heavy metal concentrations were also assessed in pregnant women's cord blood. Furthermore, the relationship between each heavy metal and height measure/catch-up growth in SGA children aged 4 years was analyzed using linear and logistic regression methods. These models were adjusted for confounders. RESULTS: We studied 4683 mother-child pairings from 103,060 pregnancies included in the Japan Environment and Children's Study. Of these, 278 pairs were also analyzed using cord blood. At 3 and 4 years old, 10.7% and 9.0% of children who were born below the 10th percentile of body weight had height standard deviation scores (SDSs) below 2, respectively. Cord blood cadmium concentrations were associated with the inability to catch up in growth by 3 or 4 years old and the height SDS at 3 years old. In maternal blood, only manganese was positively associated with the height SDS of SGA children aged 2 years; however, it was not significantly associated with catch-up growth in these children. CONCLUSION: Cadmium exposure is associated with failed catch-up development in SGA children. These new findings could help identify children highly at risk of failing to catch up in growth, and could motivate the elimination of heavy metal (especially cadmium) pollution to improve SGA children's growth.

A role of gut-brain axis on prophylactic actions of arketamine in male mice exposed to chronic restrain stress.

The gut-brain axis, which includes gut microbiota and microbiome-derived metabolites, might be implicated in depression. We reported the sustained prophylactic effects of a new antidepressant arketamine in chronic restrain stress (CRS) model of depression. In this study, we investigated the role of gut-brain axis on the prophylactic effects of arketamine in the CRS (7 days) model. Pretreatment with arketamine (10 mg/kg, 1 day prior to the CRS onset) significantly prevented CRS-induced body weight loss, increased immobility time of forced swimming test, decreased sucrose preference of sucrose preference test, and reduced expressions of synaptic proteins (GluA1 and PSD-95) in the prefrontal cortex (PFC) in the male mice. Gut microbiota analysis showed that pretreatment with arketamine might restore altered abundance of gut microbiota in CRS-exposed mice. An untargeted metabolomics analysis revealed four metabolites (e.g., L-leucine, N-acetyl-l-glutamine, 2-(2,4-dichlorophenyl)-3-[4-(dimethylamino)phenyl]acrylonitrile, L-threonine amide) that were altered between control and CRS group; however, there were found to be altered between the saline + CRS group and the arketamine + CRS group. Network analysis demonstrated correlations among synaptic proteins in the PFC and certain microbiota, and blood metabolites. These findings suggest that gut-brain axis, including its metabolites, might partially contribute to the persistent prophylactic effects of arketamine in the CRS model.

Depression-like phenotypes in mice following common bile duct ligation: Insights into the gut-liver-brain axis via the vagus nerve.

Depression frequently occurs in patients with liver cirrhosis, yet the reasons for this correlation are not fully understood. Dysbiosis of gut microbiota has been implicated in depression through the gut-brain axis via the vagus nerve. This study explored the potential role of the gut-liver-brain axis via the vagus nerve in depression-like phenotypes in mice with liver cirrhosis. These mice underwent common bile duct ligation (CBDL), a method used to stimulate liver cirrhosis. To assess depression-like behaviors, behavioral tests were conducted 10 days following either sham or CBDL surgeries. The mice with CBDL displayed symptoms such as splenomegaly, elevated plasma levels of interleukin-6 and tumor necrosis factor-α, depression-like behaviors, decreased levels of synaptic proteins in the prefrontal cortex (PFC), disrupted gut microbiota balance, and changes in blood metabolites (or lipids). Additionally, there were positive or negative correlations between the relative abundance of microbiome and behavioral data or blood metabolites (or lipids). Significantly, these changes were reversed in CBDL mice by performing a subdiaphragmatic vagotomy. Intriguingly, depression-like phenotypes in mice with CBDL were improved after a single injection of arketamine, a new antidepressant. These results suggest that CBDL-induced depression-like phenotypes in mice are mediated through the gut-liver-brain axis via the subdiaphragmatic vagus nerve, and that arketamine might offer a new treatment approach for depression in liver cirrhosis patients.

The Population-Attributable Fractions of Small-for-Gestational-Age Births: Results from the Japan Birth Cohort Consortium.

A fetal growth restriction is related to adverse child outcomes. We investigated risk ratios and population-attributable fractions (PAF) of small-for-gestational-age (SGA) infants in the Japanese population. Among 28,838 infants from five ongoing prospective birth cohort studies under the Japan Birth Cohort Consortium, two-stage individual-participant data meta-analyses were conducted to calculate risk ratios and PAFs for SGA in advanced maternal age, pre-pregnancy underweight, and smoking and alcohol consumption during pregnancy. Risk ratio was calculated using modified Poisson analyses with robust variance and PAF was calculated in each cohort, following common analyses protocols. Then, results from each cohort study were combined by meta-analyses using random-effects models to obtain the overall estimate for the Japanese population. In this meta-analysis, an increased risk (risk ratio, [95% confidence interval of SGA]) was significantly associated with pre-pregnancy underweight (1.72 [1.42-2.09]), gestational weight gain (1.95 [1.61-2.38]), and continued smoking during pregnancy (1.59 [1.01-2.50]). PAF of underweight, inadequate gestational weight gain, and continued smoking during pregnancy was 10.0% [4.6-15.1%], 31.4% [22.1-39.6%], and 3.2% [-4.8-10.5%], respectively. In conclusion, maternal weight status was a major contributor to SGA births in Japan. Improving maternal weight status should be prioritized to prevent fetal growth restriction.

Within-individual relationships between mother-to-infant bonding and postpartum depressive symptoms: a longitudinal study.

BACKGROUND: Although the importance of the dynamic intra-individual relationship between mother-to-infant bonding and postpartum depressive symptoms has been widely recognized, the complex interplay between them is not well understood. Furthermore, the potential role of prenatal depressive symptoms and infant temperament in this relationship remains unclear. This study aims to examine the bidirectional influence of mother-to-infant bonding on postpartum depressive symptoms within individuals and to elucidate whether prenatal depressive symptoms and infant temperament would influence deviations from stable individual states. METHODS: Longitudinal data were collected from 433 women in early pregnancy. Of these, 360 participants completed the main questionnaires measuring impaired mother-to-infant bonding and postpartum depressive symptoms at least once during the postpartum period. Data were collected at early and late pregnancy and several postpartum time points: shortly after birth and at one, four, ten, and 18 months postpartum. We also assessed prenatal depressive symptoms and infant temperament. A random-intercept cross-lagged panel model was used. RESULTS: Within-individual variability in mother-to-infant bonding, especially anger and rejection, significantly predicted subsequent postpartum depressive symptoms. However, the inverse relationship was not significant. Additionally, prenatal depressive symptoms and difficult infant temperament were associated with greater within-individual variability in impaired mother-to-infant bonding and postpartum depressive symptoms. CONCLUSIONS: The present study demonstrated that the within-individual relationship between mother-to-infant bonding and postpartum depressive symptoms is likely non-bidirectional. The significance of the findings is underscored by the potential for interventions aimed at improving mother-to-infant bonding to alleviate postpartum depressive symptoms, suggesting avenues for future research and practice.

The association between clustering based on composition of volatile organic compound in indoor air and building-related symptoms.

Volatile organic compounds (VOCs) have been suspected to cause building-related symptoms (BRSs). Although some studies investigated the association between BRSs and VOCs in indoor air, those results were inconsistent. This study investigated the contamination status of VOCs in the indoor air of 154 houses in Japan. Additionally, these samples were grouped by hierarchical clustering analysis based on the VOC composition, and the relationship between a VOC cluster and the BRSs was investigated. The median concentration of the sum of VOCs (ΣVOCs) was 140 µg m-3 (range: 18-3500 µg m-3). The levels of acetaldehyde in four samples and p-dichlorobenzene in one sample exceeded the guideline value. As a result of the hierarchical clustering analysis, the samples in this study were divided into six characteristic clusters based on the VOC composition. The ΣVOCs in cluster 1 were significantly lower than those in other clusters. In cluster 2, acyclic and aromatic hydrocarbons were dominant. Cluster 3 had a relatively high proportion of limonene. In cluster 4, the concentrations and composition ratios of α-pinene were higher than those of other clusters. In cluster 5, p-dichlorobenzene accounted for 42 %-72 % of the total VOCs. Cluster 6 had a relatively high proportion of decamethyl cyclopentasiloxane. This clustering likely depended on the construction of houses and lifestyles. As a result of logistic regression analysis, cluster 5 was associated with the cough symptoms of the BRSs. The results of the present study suggest that investigating the association between VOCs and BRSs is necessary to consider not only total concentrations such as TVOC and ΣVOCs but also VOC composition.

Teenage and young adult pregnancy and depression: findings from the Japan environment and children's study.

Teenage pregnancy increases the threat of depression because of its many factors. Pregnancy during young adulthood may also have several risk factors for depression compared to older pregnancies. However, data on depression in young adult pregnancies are lacking. This study investigated the association between teenage and young adult pregnancy and depression. Data from the Japan Environment and Children's study was used as a nationwide multicenter prospective cohort study. A multivariate logistic regression was performed to investigate the association between age groups (14-19, 20-24, 25-29, 30-34, ≥ 35 years) and depression, adjusted for behavioral and sociodemographic characteristics. Depression was assessed using the Kessler Psychological Distress Scale. In total, 96,808 pregnant women responded to the questionnaire. Teenage (14-19 years) and young adult (20-24 years) pregnancy were associated with an increased risk of depression compared to older pregnancy (≥ 35 years) (teenage: OR 4.28, 95% confidence interval, CI [3.24-5.64]; young adult: OR 3.00, 95% CI [2.64-3.41]). After adjusting for covariates, the magnitude of the risk of depression was attenuated. However, teenage and young adult pregnancy remained at a significantly increased risk of depression compared to older pregnancy (teenage: OR 2.38, 95% CI [1.77-3.21]; young adult: OR 2.14, 95% CI [1.87-2.46]). Our findings indicate that teenage and young adults' pregnancy are at an increased risk of depression compared to older pregnancy. These findings suggest prioritizing teenage and young pregnant women for prevention and interventions related to depression.

Role of the gut-brain axis via the subdiaphragmatic vagus nerve in stress resilience of 3,4-methylenedioxymethamphetamine in mice exposed to chronic restrain stress.

3,4-Methylenedioxymethamphetamine (MDMA) is the most widely used illicit substance worldwide. Nevertheless, recent observational studies demonstrated that lifetime MDMA use among U.S. adults was associated with a lower risk of depression and suicide thoughts. We recently reported that the gut-brain axis may contribute to MDMA-induced stress resilience in mice. To further explore this, we investigated the effects of subdiaphragmatic vagotomy (SDV) in modulating the stress resilience effects of MDMA in mice subjected to chronic restrain stress (CRS). Pretreatment with MDMA (10 mg/kg/day for 14 days) blocked anhedonia-like behavior and reduced expression of synaptic proteins and brain-derived neurotrophic factor in the prefrontal cortex (PFC) of CRS-exposed mice. Interestingly, SDV blocked the beneficial effects of MDMA on these alterations in CRS-exposed mice. Analysis of gut microbiome revealed alterations in four measures of α-diversity between the sham + MDMA + CRS group and the SDV + MDMA + CRS group. Moreover, specific microbes differed between the vehicle + CRS group and the MDMA + CRS group, and further differences in microbial composition were observed among all four groups. Untargeted metabolomics analysis showed that SDV prevented the increase in plasma levels of three compounds [lactic acid, 1-(2-hydroxyethyl)-2,2,6-tetramethyl-4-piperidinol, 8-acetyl-7-hydroxyvumaline] observed in the sham + MDMA + CRS group. Interestingly, positive correlations were found between the plasma levels of two of these compounds and the abundance of several microbes across all groups. In conclusion, our data suggest that the gut-brain axis via the subdiaphragmatic vagus nerve might contribute to the stress resilience of MDMA.

Effect of nausea and vomiting during pregnancy on mother-to-infant bonding and the mediation effect of postpartum depression: the Japan Environment and Children's Study.

BACKGROUND: Mother-to-infant bonding (MIB) is critical for the health and well-being of the mother and child. Furthermore, MIB has been shown to boost the social-emotional development of infants, while also giving mothers a sense of happiness in raising their children. Nausea and vomiting during pregnancy (NVP) is a normal complication of pregnancy, occurring in approximately 50-90% of pregnant women in the early stages of pregnancy. Despite widespread knowledge of MIB and postpartum depression, little research attention has been given to the effects of NVP on MIB. This study aimed to investigate the relationship between NVP and MIB and the mediating effects of postpartum depression. METHODS: We analyzed the data of 88,424 infants and 87,658 mothers from the Japan Environment and Children's Study (JECS), which is a government-funded nationwide birth prospective cohort study. The Japanese version of the Mother-to-Infant Bonding Scale (MIBS-J) was used to assess MIB, and the Edinburgh Postpartum Depression Scale (EPDS) was utilized to assess postpartum depression. We divided participants into four groups according to a self-reported questionnaire assessing NVP (No NVP, Mild NVP, Moderate NVP, and Severe NVP). MIB disorder was defined as a MIBS-J score ≥ 5. Logistic analysis was performed to evaluate the effect of NVP on MIB disorder at one year after delivery. A mediation analysis was conducted to examine whether postpartum depression mediated the association between NVP and MIBS-J scores. RESULTS: The logistic regression analysis results revealed reduced risks of MIB disorder among mothers with Moderate NVP (adjusted OR 0.93; 95% confidence interval, 0.86-0.99) and Severe NVP (adjusted OR 0.81; 95% confidence interval, 0.74-0.89), compared to those with No NVP. The mediation analysis revealed that NVP positively correlated with MIBS-J score in the indirect effect via postpartum depression, while NVP (Mild NVP, Moderate NVP, and Severe NVP) negatively correlated with MIBS-J score in the direct effect. CONCLUSION: The risks of MIB disorder were reduced in the Moderate NVP and Severe NVP mothers, although NVP inhibited the development of MIB via postpartum depression. The development of effective interventions for postpartum depression is important to improve MIB among mothers with NVP.

Prediction of gestational diabetes mellitus using machine learning from birth cohort data of the Japan Environment and Children's Study.

Recently, prediction of gestational diabetes mellitus (GDM) using artificial intelligence (AI) from medical records has been reported. We aimed to evaluate GDM-predictive AI-based models using birth cohort data with a wide range of information and to explore factors contributing to GDM development. This investigation was conducted as a part of the Japan Environment and Children's Study. In total, 82,698 pregnant mothers who provided data on lifestyle, anthropometry, and socioeconomic status before pregnancy and the first trimester were included in the study. We employed machine learning methods as AI algorithms, such as random forest (RF), gradient boosting decision tree (GBDT), and support vector machine (SVM), along with logistic regression (LR) as a reference. GBDT displayed the highest accuracy, followed by LR, RF, and SVM. Exploratory analysis of the JECS data revealed that health-related quality of life in early pregnancy and maternal birthweight, which were rarely reported to be associated with GDM, were found along with variables that were reported to be associated with GDM. The results of decision tree-based algorithms, such as GBDT, have shown high accuracy, interpretability, and superiority for predicting GDM using birth cohort data.

Maternal antibiotic exposure and childhood allergies: The Japan Environment and Children's Study.

Background: The association of maternal antibiotic exposure during pregnancy with childhood allergic diseases remains unclear. Objective: We aimed to evaluate the association of maternal exposure to antibiotic use during pregnancy with childhood allergic diseases up to the age of 3 years by using data from a large Japanese birth cohort. Methods: We analyzed data on 78,678 pregnant women and their offspring aged 0 to 3 years. Prenatal antibiotic exposure was defined as the use of any antimicrobial agent during pregnancy. Information was collected from maternal interviews and medical record transcripts. The outcome variables in this study included preschool asthma, wheezing, food allergy, atopic dermatitis, eczema, allergic rhinoconjunctivitis, and any allergic disease. We used logistic regression analysis to evaluate the association of antibiotic exposure during pregnancy with childhood allergic diseases. Results: Among the participating mothers, 28.5% used antibiotics during pregnancy. Antibiotic exposure during pregnancy was associated with preschool asthma (adjusted odds ratio [aOR] = 1.12 [95% CI = 1.06-1.19]), wheezing (aOR = 1.11 [95% CI = 1.07-1.15]), allergic rhinoconjunctivitis (aOR = 1.10 [95% CI = 1.03-1.17]) and any allergic disease (aOR = 1.09 [95% CI = 1.05-1.14]) in offspring up to age 3 years. In contrast, maternal antibiotic use was not associated with food allergies, atopic dermatitis, or eczema. Additionally, the significant associations were not influenced by the timing of antibiotic exposure, sex of the infants, or maternal history of allergies. Conclusion: Maternal antibiotic exposure during pregnancy is associated with an increased risk of childhood respiratory allergies.

Screen Time and Developmental Performance Among Children at 1-3 Years of Age in the Japan Environment and Children's Study.

Importance: It is unclear whether increased television (TV) and DVD viewing in early childhood from age 1 year decreases development or whether poor development increases TV/DVD viewing. Objective: To investigate the directional association between TV/DVD screen time and performance on developmental screeners in children aged 1 to 3 years. Design, Setting, and Participants: This longitudinal cohort study analyzed data from 57 980 children and mothers from a national birth cohort, the Japan Environment and Children's Study. Data were collected in collaboration with 15 regional centers across Japan. The mothers were recruited between January 2011 and March 2014. Analyses using random intercept, cross-lagged panel models were performed for children aged 1, 2, and 3 years. Of 100 303 live births, children with missing developmental screening test scores and screen time data, those with congenital diseases or cerebral palsy, and those diagnosed with an autism spectrum disorder were excluded. Statistical analyses were conducted from October 2022 to July 2023. Exposures: TV and DVD screen time. Main Outcomes and Measures: Child development at ages 1, 2, and 3 years was assessed via the mother's or guardian's report using the Ages and Stages Questionnaire, third edition. Results: Of 57 980 included children, 29 418 (50.7%) were male, and the mean (SD) maternal age at delivery was 31.5 (4.9) years. A negative association between screen time and developmental scores was observed. Increased TV/DVD screen times at age 1 and 2 years were associated with lower developmental scores at age 2 and 3 years, respectively (2 years: ß = -0.05; 95% CI, -0.06 to -0.04; 3 years: ß = -0.08; 95% CI, -0.09 to -0.06). An obverse association was observed from the Ages and Stages Questionnaires, third edition, score in the communication domain at age 1 and 2 years to subsequent screen time (2 years: γ = -0.03; 95% CI, -0.04 to -0.02; 3 years: γ = -0.06; 95% CI, -0.07 to -0.04). Conclusions and Relevance: In this study, increased TV/DVD screen time from age 1 year negatively affected later development. To reduce the negative consequences of excessive media use, researchers and health care professionals should encourage family media management and recommend social support for parents who tend to rely on the media.

Spatiotemporal patterns of spontaneous movement in neonates are significantly linked to risk of autism spectrum disorders at 18 months old.

Infants make spontaneous movements from the prenatal period. Several studies indicate that an atypical pattern of body motion during infancy could be utilized as an early biomarker of autism spectrum disorders (ASD). However, to date, little is known about whether the body motion pattern in neonates is associated with ASD risk. The present study sought to clarify this point by examining, in a longitudinal design, the link between features of spontaneous movement at about two days after birth and ASD risk evaluated using the Modified Checklist for Autism in Toddlers by their caregivers at 18 months old. The body movement features were quantified by a recently developed markerless system of infant body motion analysis. Logistic regression analysis revealed that ASD risk at 18 months old is associated with the pattern of spontaneous movement at the neonatal stage. Further, logistic regression based on body movement features during sleep shows better performance in classifying high- and low-risk infants than during the awake state. These findings raise the possibility that early signs of ASD risk may emerge at a developmental stage far earlier than previously thought.

A Double-Blind, Randomized, Placebo-Controlled Trial of the Effect of 1-Kestose on Defecation Habits in Constipated Kindergarten Children: A Pilot Study.

Constipation is common in children and can significantly affect quality of life. Prebiotics are reportedly helpful for constipation in adults, but few studies have examined their use in young children. In this study, the effect of 1-kestose (kestose), which has excellent bifidobacterial growth properties, on constipation in kindergarten children (n = 11) was compared with that of maltose (n = 12) in a randomized, double-blind study. Three grams of kestose per day for 8 weeks did not affect stool properties, but significantly increased the number of defecations per week (Median; 3 → 4 times/week, p = 0.017, effect size = 0.53). A significant decrease in Intestinibacter, a trend toward increased bifidobacteria, and a trend toward decreased Clostridium sensu stricto were observed after kestose ingestion, while concentrations of short-chain fatty acids in stools were unchanged.

Abnormal compositions of gut microbiota and metabolites are associated with susceptibility versus resilience in rats to inescapable electric stress.

BACKGROUND: Increasing evidence suggests the role of gut microbiota in resilience versus vulnerability after stress. However, the role of gut microbiota and microbiome-derived metabolites in resilience versus susceptibility in rodents exposed to stress remains unclear. METHODS: Adult male rats were exposed to inescapable electric stress under the learned helplessness (LH) paradigm. The composition of gut microbiota and metabolites in the brain and blood from control (no stress) rats, LH resilient rats, and LH susceptible rats were examined. RESULTS: At the genus level, the relative abundances of Asaccharobacter, Eisenbergiella, and Klebsiella in LH susceptible rats were significantly higher than that of LH resilient rats. At the species level, the relative abundances of several microbiome were significantly altered between LH susceptible rats and LH resilient rats. Furthermore, there were several metabolites in the brain and blood altered between LH susceptible rats and LH resilient rats. A network analysis showed correlations between the abundance of several microbiome and metabolites in the brain (or blood). LIMITATIONS: Detailed roles of microbiome and metabolites are unclear. CONCLUSIONS: These findings suggest that abnormal compositions of the gut microbiota and metabolites might contribute to susceptibility versus resilience in rats subjected to inescapable electric foot shock.