Search

Abstract Moyamoya disease (MMD) is a rare cerebrovascular disease endemic in East Asia. The p.R4810K mutation in RNF213 gene confers a risk of MMD, but other factors remain largely unknown. We tested the association of gut microbiota with MMD. Fecal samples were collected from 27 patients with MMD, 7 patients with non-moyamoya intracranial large artery disease (ICAD) and 15 control individuals with other disorders, and 16S rRNA were sequenced. Although there was no difference in alpha diversity or beta diversity between patients with MMD and controls, the cladogram showed Streptococcaceae was enriched in patient samples. The relative abundance analysis demonstrated that 23 species were differentially abundant between patients with MMD and controls. Among them, increased abundance of Ruminococcus gnavus > 0.003 and decreased abundance of Roseburia inulinivorans

Lignan polyphenols derived from plants are metabolized by bacteria in the gut to mammalian lignans, such as enterolactone (ENL) and enterodiol (END). Mammalian lignan intake has been reported to be associated with obesity and low blood glucose levels. However, the factors that are responsible for individual differences in the metabolic capacity for ENL and END are not well understood. In the present study, the effects of enterotypes of isoflavone metabolism, equol producers (EQP) and O-desmethylangolensin producers (O-DMAP), on lignan metabolism were examined. EQP was defined by urinary daidzein (DAI) and equol concentrations as log(equol/DAI) ≥ -1.42. O-DMAP was defined by urinary DAI and O-DMA concentrations as O-DMA/DAI > 0.018. Isoflavone and lignan concentrations in urine samples from 440 Japanese women were measured by gas chromatography-mass spectrometry. Metabolic enterotypes were determined from the urinary equol and O-DMA concentrations. Urinary END and ENL concentrations were compared in four groups, combinations of EQP (+/-) and O-DMAP (+/-). The urinary lignan concentration was significantly higher in the O-DMAP/EQP group (ENL: P

Background: Zinc absorption and competition among gut bacteria have been reported in animal studies. Thus, gut bacteria may modify zinc availability in humans. Metabolism of intestinal bacteria is known to be necessary for the activation of several phytoconstituents in the body. For example, equol, a typical substance of soybean isoflavone, is produced by intestinal bacteria metabolizing daidzein and the enterotype is one of distinct ones among Japanese population. The difference in the intestinal microflora can modify the bioavailability of zinc. In this study, we examined urinary zinc concentrations in adult female equol producers (EQPs). Methods: Urine samples from women participating in health examinations in Miyagi, Okinawa, Kyoto, Kochi, and Hokkaido prefectures were used; from total 17,484 samples, approximately 25 samples were randomly selected for each age group from 30 to 60 years per region (subsample: n = 520), and 520 samples with available urinary zinc concentration (determined by flame atomic absorption analysis) and enterobacterial type were analyzed. EQP was defined as log(equol/daidzein) ≥ −1.42, and urinary concentrations were corrected for creatinine concentration. Urinary zinc concentrations were compared by Student’s t-test and multiple regression analyses. Results: The geometric mean urinary zinc concentration (µg/g-Cr) was lower in EQP than in non-EQP (p = 0.0136 by t-test after logarithm transformation). On the other hand, there was no correlation between urinary zinc concentration with daidzein (r = −0.0495, P = 0.436) and equol concentrations (r = −0.0721, P = 0.256). There was a significant negative association between urinary zinc concentration and EQP (β = −0.392, P = 0.0311) after adjusting with other potential confounding variables, such as daidzein intake. Conclusions: The results suggest that gut bacteria that produce equol are involved in the metabolism of zinc. Based on previous studies, the bacteria that affect the metabolism of both substances are thought to be Enterococcus. Future studies are expected to identify specific intestinal bacteria for zinc availability and understand individual differences in the effects of micronutrients.

Abstract Isoflavones found in soy products are a promising class of nutrients that may have a positive effect on human health. In particular, the phytoestrogen metabolite equol is associated with a reduced risk of developing female hormone-related diseases. However, the effect of equol on estrogen remains unclear. Equol can modify blood and urinary estradiol (E2) levels. The aim of this cross-sectional study was to examine the associations between urinary estrogen levels, equol levels, and equol production status in Japanese women. We analyzed urine samples from 520 women by gas chromatography-mass spectrometry. Urinary E2 and 4-hydroxylated E2 levels were higher in equol producers (EQP) than in non-EQPs (P

Background: Per- and polyfluoroalkyl substances (PFASs) are highly fluorinated organic compounds that have been widely used in industry during the past few decades. The main exposure routes for PFASs are thought to be the diet, drinking water, and dust. In this study, we aimed to evaluate the relationship between perfluoroalkyl carboxylic acids (PFCAs, members of the PFAS family) and the plasma eicosapentaenoic acid-to-arachidonic acid ratio (EPA/AA), a biological indicator of seafood intake, to determine whether seafood intake may represent a means of exposure to PFASs in the Japanese population. Methods: We performed a cross-sectional study using 131 plasma samples collected from residents of Kyoto, Japan in 2013 and held in the Kyoto University biological sample bank. The concentrations of perfluoroheptanoic acid (PFHpA), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluoroundecanoic acid (PFDA), perfluoroundecanoic acid (PFUnDA), perfluorododecanoic acid (PFDoDA), perfluorotridecanoic acid (PFTrDA), EPA, and AA were quantified by gas chromatography-mass spectrometry, and multiple linear regression was used to analyze the results. Results: In multiple linear regression analyses with age and eGFR, PFOA showed a significant positive linear association with age (p = 0.0005); PFHpA showed a significant negative linear association with estimated glomerular filtration rate (eGFR; p = 0.0338); and PFHpA, PFOA, PFNA, PFUnDA, and PFDoDA exhibited significant positive linear associations with EPA/AA (p = 0.0358, 0.0056, 0.0242,

Background: In the Great East Japan Earthquake of 11 March 2011, an earthquake and accompanying tsunami struck the Tohoku region of northeastern Japan. Buildings collapsed and the tsunami spread waste, including hazardous materials. This study aimed to determine the concentrations of persistent organic pollutants (POPs) in the breast milk of mothers living in the disaster-affected area of Sendai 1 year after the earthquake. Temporal trends in the POPs concentrations were evaluated by comparison with previous studies. Methods: One hundred breast milk samples were obtained from lactating mothers at a hospital in Sendai in 2012. The results were compared with those from other years to examine whether there were changes in the POPs concentrations after the earthquake. We measured polychlorinated biphenyls (PCBs) and organochlorine pesticides, such as chlordanes, using gas chromatography-mass spectrometer (GC-MS) with negative chemical ionization, and dichlorodiphenyl trichloroethane (DDT) and its metabolites using GC-MS with electron impact ionization. Results: The mean total PCBs (11 congeners), total chlordane, and total DDT concentrations were 76.2 ng/g lipid, 39.8 ng/g lipid, and 73.5 ng/g lipid, respectively. For the samples collected in 2012, the concentrations of POPs in breast milk showed minimal changes compared with results from previous years for samples collected at the same hospital in Sendai. Conclusions: Our study demonstrates that 1 year after the earthquake and tsunami, the concentrations of chlorinated POPs in breast milk had not changed substantially.

Phthalates are used as plasticizers in many products used in daily life worldwide. Due to industrial and economic developments, exposure among general population to phthalates may vary geographically and temporally. However, studies are lacking for investigating temporal changes in phthalate exposure in the Japanese population. In the present study, the temporal trends in exposure to various phthalates were assessed among a group of Japanese adult female population over 1993–2016 and derived associated risks. For this purpose, urine samples of healthy Japanese females in Kyoto, Japan (N = 132) collected in 1993, 2000, 2003, 2009, 2011, and 2016, were employed and measured for the concentrations of 18 phthalate metabolites. Over this period, the detection rates of mono(3-carboxypropyl) phthalate (MCPP) and monoisobutyl phthalate (MiBP) decreased, and the geometric means of the urinary concentrations of mono(2-ethyl-5-carboxypentyl) phthalate (MECPP), and mono(2-ethyl-5-oxohexyl) phthalate (MEOHP) showed a significant decreasing trend. Cumulative risk due to exposure to dibutyl phthalate (DBP), diisobutyl phthalate (DiBP), butyl benzyl phthalate (BBP), and di-2-ethylhexyl phthalate (DEHP) showed a dramatic decrease only between 1993 and 2000. The maximum hazard quotient (HQM) was attributed to DEHP in most subjects regardless of sampling year. This study showed the temporal trend of the exposure of Japanese females to several phthalate esters over two decades. As of the late 2010’s, DEHP was still the predominant component of phthalate ester exposure in the population. The HI value, however, indicates that direct risk due to phthalate exposure was unlikely among the studied population.

The number of COVID-19 patients in Japan is considered low, compared with U.S. and European countries. However, recent serological survey reported that several percent of population showed IgG positive to SARS-CoV-2. Specificity in the assays might influence the estimate, and possibility of overdiagnosis should be investigated. Serological tests for SARS-CoV-2 coronavirus were performed in pre-COVID-19 sera in Japan (400 healthy subjects in 2012–2015). Lateral flow assay (LFA) and enzyme-linked immunosorbent assay (ELISA) showed 1.5% (6/400) and 1.75% (7/400) IgG positives, respectively. Among those false positive samples, only one sample was positive in both LFA and ELISA (0.25%; 95% CI: 0.006–1.39%). Possible bias from pooling method was examined by Monte Carlo method and the possibility was unlikely at low false positive rate. Previous surveys might overestimate COVID-19 seroprevalence in several populations of Japan. These false positives could be excluded by combination of different diagnostics. Nonetheless, the result of seroprevalence should be carefully interpreted in less prevalent areas.

The fetal toxicities of multi-wall carbon nanotubes (MWCNTs) with various sizes were compared in CD1(ICR) mice. MWCNTs were suspended in 2% sodium carboxymethyl cellulose solution in phosphate-buffered saline. On day 9 of gestation, dams were administered a single intraperitoneal dose of MWCNTs (4 mg/kg body weight), while dams in the control group were administered vehicle (10 mL/kg body weight). The rectal temperatures of the dams were monitored 2 h after administaration to asses statuses of the dams. The dams and fetuses were examined on day 18 of gestation. The number of live fetus per dam decreased in some MWCNTs-administered groups. The mean percentages of live fetuses in total implantations in the MWCNTs-administered groups markedly varied from 0% to 95%, and the highest mean percentage of live fetuses in the MWCNTs-administered group was equivalent to that of the control group. The decrease in live fetuses depended on an increased number of early dead fetuses. In the groups with markedly lowered rectal temperature after administration, the fetal loss were evident. The blood levels of interleukin-6 and/or monocyte chemoattractant protein-1 in dam 2 h after administration of MWCNTs markedlyr increased, especially in the goups with significant decrease in live fetuses. These results indicated a relationship between inflammation in the dam, which probabely depended on the particular length of the MWCNTs, and the fetal toxicioty of MWCNTs in mice.