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result(s) for
"Sai, Yoshimichi"
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CCR5 Plays a Critical Role in Obesity-Induced Adipose Tissue Inflammation and Insulin Resistance by Regulating Both Macrophage Recruitment and M1/M2 Status
by
Ota, Tsuguhito
,
Inoue, Hiroshi
,
Yamamoto, Hiroshi
in
Adipocytes
,
Adipose tissue
,
Adipose Tissue - metabolism
2012
C-C motif chemokine receptor (CCR)2 and its ligand, monocyte chemoattractant protein (MCP)-1, are pivotal for adipose tissue macrophage (ATM) recruitment and the development of insulin resistance. However, other chemokine systems also may play a role in these processes. In this study, we investigated the role of CCR5 in obesity-induced adipose tissue inflammation and insulin resistance. We analyzed expression levels of CCR5 and its ligands in white adipose tissue (WAT) of genetically (ob/ob) and high-fat (HF) diet-induced obese (DIO) mice. Furthermore, we examined the metabolic phenotype of Ccr5(-/-) mice. CCR5 and its ligands were markedly upregulated in WAT of DIO and ob/ob mice. Fluorescence-activated cell sorter analysis also revealed that DIO mice had a robust increase in CCR5(+) cells within ATMs compared with chow-fed mice. Furthermore, Ccr5(-/-) mice were protected from insulin resistance, glucose intolerance, and hepatic steatosis induced by HF feeding. The effects of loss of CCR5 were related to both reduction of total ATM content and an M2-dominant shift in ATM polarization. It is noteworthy that transplantation of Ccr5(-/-) bone marrow was sufficient to protect against impaired glucose tolerance. CCR5 plays a critical role in ATM recruitment and polarization and subsequent development of insulin resistance.
Journal Article
Limited Impact of Murine Placental MDR1 on Fetal Exposure of Certain Drugs Explained by Bypass Transfer Between Adjacent Syncytiotrophoblast Layers
2022
PurposeMultidrug resistance protein 1 (MDR1) is located at the interface between two syncytiotrophoblast layers in rodent placenta, and may influence fetal drug distribution. Here, we quantitatively compare the functional impact per single MDR1 molecule of MDR1 at the placental barrier and blood-brain barrier in mice.MethodsMDR1A and MDR1B proteins were quantified by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Paclitaxel or digoxin was continuously administered to pregnant Mdr1a−/−/Mdr1b−/− or wild-type mice, and the drug concentrations in the maternal and fetal plasma and maternal brain were quantified by LC-MS/MS.ResultsMDR1A and MDR1B proteins are expressed in the membrane of mouse placental labyrinth, and total MDR1 at the placental barrier amounts to about 30% of that at the blood-brain barrier. The fetal-to-maternal plasma concentration ratio of digoxin was only marginally affected in Mdr1a−/−/Mdr1b−/− mice, while that of paclitaxel showed a several-fold increase. No such difference between the two drugs was found in the maternal brain distribution. The impact per single MDR1 molecule on the fetal distribution of digoxin was calculated to be much lower than that on the brain distribution, but this was not the case for paclitaxel. Our pharmacokinetic model indicates that the impact of placental MDR1 is inversely correlated to the ratio of permeability through gap junctions connecting the two syncytiotrophoblast layers to passive diffusion permeability.ConclusionOur findings indicate that murine placental MDR1 has a minimal influence on the fetal concentration of certain substrates, such as digoxin, due to bypass transfer, probably via connexin26 gap junctions.
Journal Article
Competitiveness and individual characteristics: a double-blind placebo-controlled study using oxytocin
by
Okudaira, Hiroko
,
Sai, Yoshimichi
,
Tsubouchi, Kiyotaka
in
631/378/2645
,
631/378/3919
,
631/45/776
2020
Oxytocin-enhanced prosocial behaviour depends on individual characteristics. This study investigated the relationship between oxytocin and competitiveness, which is another important social trait and predicts economic and social outcomes. In this double-blind, randomized, and placebo-controlled study of 192 male participants, we examined whether oxytocin moderates competitiveness and whether the effect of oxytocin on competitiveness is amplified in individuals with autistic traits. While our results show no relationship between oxytocin and competitiveness, we observed suggestive patterns: albeit not significantly, oxytocin reduced and enhanced competitiveness among participants without autistic traits and among their counterparts with autistic traits, respectively.
Journal Article
Validation of an automated sample preparation module directly connected to LC-MS/MS (CLAM-LC-MS/MS system) and comparison with conventional immunoassays for quantitation of tacrolimus and cyclosporin A in a clinical setting
by
Kawano, Mitsuhiro
,
Shimada, Tsutomu
,
Fujita, Arimi
in
Architects
,
Automatic pretreatment
,
Automation
2024
Background
Therapeutic drug monitoring (TDM) systems generally use either liquid chromatography/tandem mass spectrometry (LC-MS/MS) or immunoassay, though both methodologies have disadvantages. In this study, we aimed to evaluate whether a CLAM-LC-MS/MS system, which consists of a sample preparation module directly connected to LC-MS/MS, could be used for clinical TDM work for immunosuppressive drugs in whole blood, which requires a hemolytic process. For this purpose, we prospectively validated this system for clinical measurement of tacrolimus and cyclosporin A in patients’ whole blood. The results were also compared with those of commercial immunoassays.
Methods
Whole blood from patients treated with tacrolimus or cyclosporin A at the Department of Nephrology and Departments of Rheumatology, Kanazawa University Hospital, from May 2018 to July 2019 was collected with informed consent, and drug concentrations were measured by CLAM-LC-MS/MS and by chemiluminescence immunoassay (CLIA) for tacrolimus and affinity column-mediated immunoassay (ACMIA) for cyclosporin A. Correlations between the CLAM-LC-MS/MS and immunoassay results were analyzed.
Results
Two hundred and twenty-four blood samples from 80 patients were used for tacrolimus measurement, and 76 samples from 21 patients were used for cyclosporin A. Intra- and inter-assay precision values of quality controls were less than 7%. There were significant correlations between CLAM-LC-MS/MS and the immunoassays for tacrolimus and cyclosporin A (Spearman rank correlation coefficients: 0.861, 0.941, P < 0.00001 in each case). The drug concentrations measured by CLAM-LC-MS/MS were about 20% lower than those obtained using the immunoassays. CLAM-LC-MS/MS maintenance requirements did not interfere with clinical operations. Compared to manual pretreatment, automated pretreatment by CLAM showed lower inter-assay precision values and greatly reduced the pretreatment time.
Conclusions
The results obtained by CLAM-LC-MS/MS were highly correlated with those of commercial immunoassay methods. CLAM-LC-MS/MS offers advantages in clinical TDM practice, including simple, automatic pretreatment, low maintenance requirement, and avoidance of interference.
Journal Article
Effect of changes in skin properties due to diabetes mellitus on the titration period of transdermal fentanyl: single-center retrospective study and diabetic animal model study
by
Shimada, Tsutomu
,
Ito, Yuriko
,
Fujita, Arimi
in
Analysis
,
Biomedical and Life Sciences
,
Biomedicine
2024
Background
In the dose titration of transdermal fentanyl to prevent unrelieved pain, it is important to consider not only dose adjustment, but also the titration period, which is influenced by the time required to reach the steady state. Many patients with cancer pain experience comorbidities that might affect the skin properties and influence transdermal absorption. We hypothesized that skin changes due to diabetes mellitus (DM) would affect the titration period of transdermal fentanyl. We conducted a retrospective study and diabetic animal model study to test this hypothesis.
Methods
In the retrospective study, the titration period was defined in terms of “dose change” and “number of rescue opioids” in patients initiated on transdermal fentanyl. Multiple logistic regression analysis was performed to analyze the relation between the titration period and comorbidities, including DM. In the diabetic animal model study, intercellular lipids of stratum corneum (SC) were analyzed in Goto-Kakizaki (GK) rats, a model of DM, and the pharmacokinetics of intravenously or transdermally administered fentanyl was examined.
Results
In the retrospective study, the titration period ranged from 5 to 39 days (n = 387), and the patients taking a longer period (6 days or more) was significantly related to in patients with unspecified DM: AOR (95% confidence interval), 0.438 (0.217–0.884). In the diabetic animal model study, the ceramides (CERs) content in the SC was decreased by approximately 30% in GK rats compared to Wistar rats. The absorption rate constant (
k
a
) of fentanyl administered transdermally was increased approximately 1.4-fold in GK rats, though there was no difference in transdermal bioavailability (
F
) or systemic clearance (
CL
tot
).
Conclusion
Our results suggest that the steady state of transdermally administered fentanyl is reached sooner in cancer patients with DM as a comorbidity. Earlier pain assessment and dose adjustment may be possible in these patients.
Journal Article
Oxytocin-Trust Link in Oxytocin-Sensitive Participants and Those Without Autistic Traits
by
Okudaira, Hiroko
,
Sai, Yoshimichi
,
Tsubouchi, Kiyotaka
in
human
,
interindividual variation
,
Neuroscience
2021
There have been numerous studies in which the biological role of oxytocin in trusting behavior has been investigated. However, a link between oxytocin and trust in humans was discovered only in one early study. We hypothesized that there is a large interindividual variation in oxytocin sensitivity, and that such variation is one reason for the doubt surrounding the role of oxytocin in trusting behavior. Here, in a double-blind, prospective, case-control study, we administered intranasal oxytocin to participants of trust and risk games. We measured salivary oxytocin concentration, relating it to the amount of money transferred among participants (a proxy for trust) and the autism-spectrum quotient (AQ). A one-sided Fisher’s exact test was performed to detect differences between the oxytocin and placebo groups in the proportions of investors who transferred the maximum amount of money. We discovered a tendency for participants who received oxytocin to transfer higher amounts of money to co-participants than those who received a placebo ( P = 0.04). We also revealed a high degree of interindividual variation in salivary oxytocin concentrations after oxytocin administration. After stratifying the samples with respect to oxytocin sensitivity, oxytocin-sensitive participants in the oxytocin group also transferred higher amounts of money than those in the placebo group ( P = 0.03), while such a tendency was not observed for oxytocin-insensitive participants ( P = 0.34). Participants with lower AQ scores (less severe autistic traits) exhibited a greater tendency toward trusting behavior after oxytocin administration than did those with higher AQ scores ( P = 0.02). A two-sample t -test that was performed to detect significant differences in the mean transfers between the oxytocin and placebo groups indicated no significant between-group difference in the mean transfers ( P = 0.08). There are two possible interpretations of these results: First, there is no effect of oxytocin on trust in humans; second, the effects of oxytocin on trust in humans is person-dependent. However, the results should be interpreted with caution as the effect size was not larger than the minimal detectable effect size and the results were not statistically significant ( P > 0.05) after Bonferroni corrections.
Journal Article
Transdermal pilocarpine on the skin over salivary glands to increase salivation: an in vivo study
by
Natsuko Ishida
,
Yoshimichi Sai
,
Satoshi Mizuno
in
Administration, Cutaneous
,
Administration, Oral
,
Agonists
2024
Background
Hyposalivation is treated using oral cholinergic drugs; however, systemic side effects occasionally lead to discontinuation of treatment. We aimed to investigate the effects of transdermal pilocarpine on the salivary gland skin on saliva secretion and safety in rats.
Methods
Pilocarpine was administered to rats orally (0.5 mg/kg) or topically on the salivary gland skin (5 mg/body). Saliva volume, the number of sweat dots, and fecal weight were measured along with pilocarpine concentration in plasma and submandibular gland tissues.
Results
Saliva volume significantly increased 0.5 h after oral administration and 0.5, 3, and 12 h after topical administration. Fecal weight and sweat dots increased significantly 1 h after oral administration; however, no changes were observed after topical application. The pilocarpine concentration in the submandibular gland tissues of the topical group was higher than that in the oral group at 0.5, 3, and 12 h of administration.
Conclusions
Pilocarpine application to salivary gland skin persistently increased salivary volume in rats without inducing sweating or diarrhea. Transdermal pilocarpine applied to the skin over the salivary glands may be an effective and safe treatment option for hyposalivation.
Journal Article
Endoplasmic Reticulum Stress Inhibits STAT3-Dependent Suppression of Hepatic Gluconeogenesis via Dephosphorylation and Deacetylation
by
Matsumoto, Michihiro
,
Yamada, Tomoko
,
Hosooka, Tetsuya
in
Acetylation
,
Animals
,
Biological and medical sciences
2012
In the liver, signal transducer and activator of transcription 3 (STAT3) plays an important role in the suppression of gluconeogenic enzyme expression. While obesity-associated endoplasmic reticulum (ER) stress has been shown to increase hepatic gluconeogenic enzyme expression, the role of ER stress in STAT3-dependent regulation of such expression is unclear. The current study aimed to elucidate the effect of ER stress on the STAT3-dependent regulation of hepatic gluconeogenic enzyme expression. Genetically obese/diabetic db/db mice and db/db mouse-derived isolated hepatocytes were used as ER stress models. A tyrosine phosphatase inhibitor, a deacetylation inhibitor, and an acetylated mutant of STAT3 were used to examine the effect of ER stress on hepatic STAT3 action. ER stress inhibited STAT3-dependent suppression of gluconeogenic enzyme gene expression by suppressing hepatic Janus kinase (JAK)2 and STAT3 phosphorylation. A tyrosine phosphatase inhibitor restored ER stress-induced suppression of JAK2 phosphorylation but exhibited no improving effect on suppressed STAT3 phosphorylation. STAT3 acetylation is known to correlate with its phosphorylation. ER stress also decreased STAT3 acetylation. An acetylated mutant of STAT3 was resistant to ER stress-induced inhibition of STAT3-phosphorylation and STAT3-dependent suppression of hepatic gluconeogenic enzyme gene expression in vitro and in vivo. Trichostatin A, a histone deacetylase (HDAC) inhibitor, ameliorated ER stress-induced inhibition of STAT3 acetylation and phosphorylation. The current study revealed that ER stress inhibits STAT3-dependent suppression of hepatic gluconeogenic enzymes via JAK2 dephosphorylation and HDAC-dependent STAT3 deacetylation, playing an important role in the increase of hepatic glucose production in obesity and diabetes.
Journal Article
Comparison of Tolerability Between 2-Weekly and 3-Weekly Docetaxel Regimen in Castration-resistant Prostate Cancer
2020
Background: The tolerability of 2-weekly docetaxel at 25-35 mg/m2 for castration-resistant prostate cancer (CRPC) has not been fully evaluated. The aim of this study was to evaluate its tolerability compared to 3-weekly docetaxel at 60-75 mg/m2 in patients with CRPC. Patients and Methods: In this retrospective study, data were compared with respect to efficacy and safety between 2-weekly and 3-weekly docetaxel regimens in patients with CRPC. Results: Time to treatment failure and prostate-specific antigen (PSA) response rate did not differ significantly between the two regimens. Compared to 3-weekly administration, incidence of severe leukopenia and febrile neutropenia was significantly lower (p<0.05), and relative dose intensity was significantly higher (p<0.05) for the 2-weekly schedule. Docetaxel dosage and PSA response were identified as independent risk factors for severe leukopenia. Conclusion: Two-weekly treatment seems better tolerated than three-weekly treatment in Japanese patients with CRPC.
Journal Article