Publications by authors named "Chiharu Ishii"

Barley is rich in β-glucan, which can alter gut microbiota and metabolome profiles, potentially affecting host metabolism. However, the microbiota and metabolites increased by barley β-glucan remain unclear. In this study, we focused on the gut-microbiota-derived metabolite succinate and investigated the microbiome and metabolome profiles altered by barley β-glucan intake.

View Article and Find Full Text PDF

A two-dimensional LC-MS/MS system has been developed for the enantioselective determination of proline (Pro), cis-4-hydroxyproline (cis-4-Hyp) and trans-4-hydroxyproline (trans-4-Hyp) in a variety of biological samples. The amino acids were pre-column derivatized with 4-fluoro-7-nitro-2,1,3-benzoxadiazole (NBD-F), and the NBD-derivatives were separated by a reversed-phase column (Singularity RP18) as their D plus L mixtures in the first dimension. The collected target fractions were then introduced into the second dimension where the enantiomers were separated by a Pirkle-type enantioselective column (Singularity CSP-001S) and determined by a tandem mass spectrometer (Triple Quad™ 5500).

View Article and Find Full Text PDF

Background: Previous research has shown a significant link between gut microbiota in children with autism spectrum disorder (ASD) and attention-deficit hyperactivity disorder (ADHD). However, much remains unknown because of the heterogeneity of disorders and the potential confounders such as dietary patterns and control group variations.

Methods: Children aged 6-12 years who had been clinically diagnosed with ASD and/or ADHD, their unaffected neurotypical siblings, and non-related neurotypical volunteers were recruited cross-sectionally.

View Article and Find Full Text PDF

For the discovery of sensitive biomarkers of kidney function focusing on chiral amino acids, a multiple heart-cutting two-dimensional (2D) liquid chromatography-mass spectrometry (LC-MS)/MS system has been designed/developed. As the target analytes, alanine (Ala), aspartic acid, glutamic acid (Glu), leucine (Leu), lysine, methionine, phenylalanine (Phe), proline (Pro), serine (Ser), and valine were selected considering the presence of their d-forms in mammals. The 2D LC-MS/MS system consisted of the nonenantioselective reversed-phase separation of the target amino acids, the separations of the d- and l-enantiomers, and detection using MS/MS.

View Article and Find Full Text PDF

A highly-selective three-dimensional high-performance liquid chromatographic (3D-HPLC) system was developed for the determination of serine (Ser), threonine (Thr) and allo-threonine (aThr) enantiomers in human plasma to screen the new biomarker of chronic kidney disease (CKD). d-Ser has been reported to be the candidate biomarker of CKD, however, multiple biomarkers are still required. Therefore, Ser analogs of hydroxy amino acids are the focus in the present study.

View Article and Find Full Text PDF
Article Synopsis
  • ATF5 is a transcription factor crucial for the differentiation and survival of sensory neurons in mouse olfactory organs, yet its specific target genes were previously unknown.
  • Chromatin immunoprecipitation-quantitative polymerase chain reaction (ChIP-qPCR) experiments identified Nhlh1 as a novel target gene for ATF5, showing that ATF5 binds to its enhancer region and influences its expression.
  • The study suggests that ATF5, along with the co-factor Lhx2, plays a vital role in regulating Nhlh1 to promote the development of olfactory and vomeronasal sensory neurons.
View Article and Find Full Text PDF

Background: The impact of the gut microbiota on neuropsychiatric disorders has gained much attention in recent years; however, comprehensive data on the relationship between the gut microbiome and its metabolites and resistance to treatment for depression and anxiety is lacking. Here, we investigated intestinal metabolites in patients with depression and anxiety disorders, and their possible roles in treatment resistance.

Results: We analyzed fecal metabolites and microbiomes in 34 participants with depression and anxiety disorders.

View Article and Find Full Text PDF

Background: Growing attention is paid to the association between alterations in the gut microbiota and their metabolites in patients with psychiatric disorders. Our study aimed to determine how gut microbiota and metabolomes are related to the sleep quality among patients with depression and anxiety disorders by analyzing the datasets of our previous study.

Methods: Samples were collected from 40 patients (depression: 32 patients [80.

View Article and Find Full Text PDF

Amino acids normally have a chiral carbon and d/l-enantiomers are present. Due to the homochirality features on the present Earth, l-enantiomers are predominant in the living beings and the d-enantiomers are rare. Along with the progress and development of cutting edge analytical methods, several d-amino acids were found even in the higher animals including humans, and their biological functions and diagnostic values have also been reported.

View Article and Find Full Text PDF

Fever is a common symptom of influenza and coronavirus disease 2019 (COVID-19), yet its physiological role in host resistance to viral infection remains less clear. Here, we demonstrate that exposure of mice to the high ambient temperature of 36 °C increases host resistance to viral pathogens including influenza virus and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). High heat-exposed mice increase basal body temperature over 38 °C to enable more bile acids production in a gut microbiota-dependent manner.

View Article and Find Full Text PDF

Mammals exhibit systemic homochirality of amino acids in L-configurations. While ribosomal protein synthesis requires rigorous chiral selection for L-amino acids, both endogenous and microbial enzymes convert diverse L-amino acids to D-configurations in mammals. However, it is not clear how mammals manage such diverse D-enantiomers.

View Article and Find Full Text PDF
Article Synopsis
  • - The intestinal immune system interacts with beneficial gut bacteria to keep a healthy balance, but stress can disrupt this balance and negatively affect brain function.
  • - Researchers found that a specific type of immune cell (γδ T cells) in the colon affects how individuals respond to chronic social stress, especially through a receptor called dectin-1.
  • - Reduced levels of certain beneficial bacteria, like Lactobacillus, lead to stress-related behavior changes, similar to those observed in people with depression, indicating a link between gut health and mental health.
View Article and Find Full Text PDF
Article Synopsis
  • * In a controlled trial, healthy active males who took α-cyclodextrin showed improved endurance performance compared to those who received a placebo.
  • * Experimentation on mice revealed that α-cyclodextrin increased swimming endurance and affected liver metabolism, suggesting it helps improve athletic performance by enhancing glucose production in the liver.
View Article and Find Full Text PDF

We aimed to investigate the impact of aging on the relationship among the composition of gut microbiota, gastrointestinal (GI) symptoms, and the course of treatment for major depressive disorder (MDD) by analyzing the datasets from our previous study. Patients with MDD were recruited, and their stools were collected at three time points (baseline, midterm, and endpoint) following the usual antidepressant treatment. Gut microbiota were analyzed using 16S rRNA gene sequencing.

View Article and Find Full Text PDF

Background: BB536 supplementation can be used to regulate bowel movements in various people, including healthy subjects and patients with irritable bowel syndrome (IBS); however, individuals vary in their responses to BB536 treatment. One putative factor is the gut microbiota; recent studies have reported that the gut microbiota mediates the effects of diet or drugs on the host. Here, we investigated intestinal features, such as the microbiome and metabolome, related to BB536 effectiveness in increasing bowel movement frequency.

View Article and Find Full Text PDF

Recently, many kinds of shoulder-support exoskeletons have been developed and some of them are commercially available. However, to the best of our knowledge, shoulder-support exoskeletons that have neck-support mechanism have not been found. During the overhead work, physical strain is added to not only upper limb and shoulder but also neck of workers since the workers work keeping their face raised.

View Article and Find Full Text PDF
Article Synopsis
  • Low body temperature is linked to poor outcomes in heart failure patients, with brown adipose tissue (BAT) playing a significant role in metabolic health and potentially influencing heart failure.
  • BAT dysfunction, demonstrated through reduced thermogenic capacity and hypoxia after heart stressors like thoracic aortic constriction (TAC) or myocardial infarction (MI), leads to adverse effects on heart function and body temperature regulation.
  • Elevated levels of plasma TMAO were associated with decreased heart energy production and function, suggesting that therapies focused on improving BAT function and reducing TMAO levels could benefit heart failure patients.
View Article and Find Full Text PDF

D-Tryptophan (D-Trp) is one of the minor D-enantiomers of amino acids discovered in microbes and mollusca. In the present study, a highly-selective 2D chiral LC-MS/MS method has been designed and developed focusing on the determination of Trp enantiomers to investigate the presence and regulation of free D-Trp in mammals. The developed system consisted of a reversed-phase separation for the first dimension, an enantioselective separation for the second dimension and also the detection using a triple quadrupole mass spectrometer for the third/fourth dimensions.

View Article and Find Full Text PDF

d-Serine modulates excitatory neurotransmission by binding to N-methyl-d-aspartate glutamate receptors. d-Amino acid oxidase (DAO) degrades d-amino acids, such as d-serine, in the central nervous system, and is associated with neurological and psychiatric disorders. However, cell types that express brain DAO remain controversial, and whether brain DAO influences systemic d-amino acids in addition to brain d-serine remains unclear.

View Article and Find Full Text PDF

A highly-selective two-dimensional high-performance liquid chromatographic (2D-HPLC, off-line heart cutting mode) system was developed for the determination of serine (Ser), threonine (Thr) and allo-threonine (aThr) enantiomers in human physiological fluids. Ser, Thr and aThr have a hydroxy group in their side chains, and the development of a simultaneous analytical method with a practically sufficient enantio/chemo-selectivity has been required to clarify their amounts in human physiological fluids. The amino acids in the samples were derivatized with 4-fluoro-7-nitro-2,1,3-benzoxadiazole and were isolated by a reversed-phase column (Singularity RP18, 1.

View Article and Find Full Text PDF

Background: It is estimated that by 2040 there will be 1,017,712 new cases of prostate cancer worldwide. Androgen deprivation therapy (ADT) is widely used as a treatment option for all disease stages. ADT, and the resulting decline in androgen levels, may indirectly affect gut microbiota.

View Article and Find Full Text PDF

Background: d-Amino acids (d-AAs) have been associated with age-associated conditions in the general population but their relevance in people with HIV (PWH), who experience accentuated/accelerated aging has not been studied. We compared d-AA levels in HIV-infected and uninfected controls and explored their association with markers of immune activation, gut permeability and organ dysfunction.

Design: Case-control analysis.

View Article and Find Full Text PDF

The gut microbiota plays a crucial role in maintaining health. Monitoring the complex dynamics of its microbial population is, therefore, important. Here, we present a deep convolution network that can characterize the dynamic changes in the gut microbiota using low-resolution images of fecal samples.

View Article and Find Full Text PDF

Background: There is growing evidence regarding the connection between alterations in gut microbiota and their metabolites in patients with depressive disorders, suggesting a potential role in pathophysiology. Our study aimed to investigate the relationship between microbial, metabolomic features and the course of treatment for depression in a real-world clinical setting.

Methods: Patients diagnosed with depressive disorders were recruited, and their stool was collected at three time points during their depression treatments.

View Article and Find Full Text PDF