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1.
Development ; 149(6)2022 03 15.
Article in English | MEDLINE | ID: mdl-35319746

ABSTRACT

For in vivo functional analysis of a protein of interest (POI), multiple transgenic strains with a POI that harbors different tags are needed but generation of these strains is still labor-intensive work. To overcome this, we have developed a versatile Drosophila toolkit with a genetically encoded single-chain variable fragment for the HA epitope tag: 'HA Frankenbody'. This system allows various analyses of HA-tagged POI in live tissues by simply crossing an HA Frankenbody fly with an HA-tagged POI fly. Strikingly, the GFP-mCherry tandem fluorescent-tagged HA Frankenbody revealed a block in autophagic flux and an accumulation of enlarged autolysosomes in the last instar larval and prepupal fat body. Mechanistically, lysosomal activity was downregulated at this stage, and endocytosis, but not autophagy, was indispensable for the swelling of lysosomes. Furthermore, forced activation of lysosomes by fat body-targeted overexpression of Mitf, the single MiTF/TFE family gene in Drosophila, suppressed the lysosomal swelling and resulted in pupal lethality. Collectively, we propose that downregulated lysosomal function in the fat body plays a role in the metamorphosis of Drosophila.


Subject(s)
Drosophila Proteins , Drosophila , Animals , Autophagy/genetics , Drosophila/metabolism , Drosophila Proteins/genetics , Drosophila Proteins/metabolism , Fat Body/metabolism , Larva/metabolism , Lysosomes/metabolism
2.
PLoS Genet ; 17(8): e1009727, 2021 08.
Article in English | MEDLINE | ID: mdl-34407079

ABSTRACT

Vps13 family proteins are proposed to function in bulk lipid transfer between membranes, but little is known about their regulation. During sporulation of Saccharomyces cerevisiae, Vps13 localizes to the prospore membrane (PSM) via the Spo71-Spo73 adaptor complex. We previously reported that loss of any of these proteins causes PSM extension and subsequent sporulation defects, yet their precise function remains unclear. Here, we performed a genetic screen and identified genes coding for a fragment of phosphatidylinositol (PI) 4-kinase catalytic subunit and PI 4-kinase noncatalytic subunit as multicopy suppressors of spo73Δ. Further genetic and cytological analyses revealed that lowering PI4P levels in the PSM rescues the spo73Δ defects. Furthermore, overexpression of VPS13 and lowering PI4P levels synergistically rescued the defect of a spo71Δ spo73Δ double mutant, suggesting that PI4P might regulate Vps13 function. In addition, we show that an N-terminal fragment of Vps13 has affinity for the endoplasmic reticulum (ER), and ER-plasma membrane (PM) tethers localize along the PSM in a manner dependent on Vps13 and the adaptor complex. These observations suggest that Vps13 and the adaptor complex recruit ER-PM tethers to ER-PSM contact sites. Our analysis revealed that involvement of a phosphoinositide, PI4P, in regulation of Vps13, and also suggest that distinct contact site proteins function cooperatively to promote de novo membrane formation.


Subject(s)
1-Phosphatidylinositol 4-Kinase/metabolism , Saccharomyces cerevisiae Proteins/metabolism , Spores, Fungal/genetics , 1-Phosphatidylinositol 4-Kinase/genetics , Adaptor Proteins, Signal Transducing/metabolism , Carrier Proteins/genetics , Cell Membrane/metabolism , Endoplasmic Reticulum/metabolism , Membranes/metabolism , Mitochondrial Membranes/metabolism , Protein Transport , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism , Saccharomyces cerevisiae Proteins/genetics
3.
Bioorg Med Chem Lett ; 43: 128048, 2021 07 01.
Article in English | MEDLINE | ID: mdl-33887438

ABSTRACT

Nicotinamide phosphoribosyltransferase (NAMPT) catalyzes the rate-limiting step of the NAD+ salvage pathway. Since NAD+ plays a pivotal role in many biological processes including metabolism and aging, activation of NAMPT is an attractive therapeutic target for treatment of diverse array of diseases. Herein, we report the continued optimization of novel urea-containing derivatives which were identified as potent NAMPT activators. Early optimization of HTS hits afforded compound 12, with a triazolopyridine core, as a lead compound. CYP direct inhibition (DI) was identified as an issue of concern, and was resolved through modulation of lipophilicity to culminate in 1-[2-(1-methyl-1H-pyrazol-5-yl)-[1,2,4]triazolo[1,5-a]pyridin-6-yl]-3-(pyridin-4-ylmethyl)urea (21), which showed potent NAMPT activity accompanied with attenuated CYP DI towards multiple CYP isoforms.


Subject(s)
Cytochrome P-450 Enzyme System/metabolism , Cytokines/metabolism , Drug Discovery , Enzyme Inhibitors/pharmacology , Nicotinamide Phosphoribosyltransferase/metabolism , Urea/pharmacology , Animals , Dose-Response Relationship, Drug , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/chemistry , Humans , Mice , Mice, Inbred C57BL , Molecular Structure , Structure-Activity Relationship , Urea/analogs & derivatives , Urea/chemistry
4.
Bioorg Med Chem Lett ; 41: 128007, 2021 06 01.
Article in English | MEDLINE | ID: mdl-33798699

ABSTRACT

NAD+ is a crucial cellular factor that plays multifaceted roles in wide ranging biological processes. Low levels of NAD+ have been linked to numerous diseases including metabolic disorders, cardiovascular disease, neurodegeneration, and muscle wasting disorders. A novel strategy to boost NAD+ is to activate nicotinamide phosphoribosyltransferase (NAMPT), the putative rate-limiting step in the NAD+ salvage pathway. We previously showed that NAMPT activators increase NAD+ levels in vitro and in vivo. Herein we describe the optimization of our NAMPT activator prototype (SBI-0797812) leading to the identification of 1-(4-((4-chlorophenyl)sulfonyl)phenyl)-3-(oxazol-5-ylmethyl)urea (34) that showed far more potent NAMPT activation and improved oral bioavailability.


Subject(s)
Cytokines/metabolism , Nicotinamide Phosphoribosyltransferase/metabolism , Urea/pharmacology , Dose-Response Relationship, Drug , Humans , Molecular Structure , Structure-Activity Relationship , Urea/analogs & derivatives , Urea/chemistry
5.
Chem Pharm Bull (Tokyo) ; 69(11): 1110-1122, 2021.
Article in English | MEDLINE | ID: mdl-34719594

ABSTRACT

Nicotinamide phosphoribosyltransferase (NAMPT) catalyzes the rate-limiting step of the nicotinamide adenine dinucleotide (NAD+) salvage pathway. Because NAD+ plays a pivotal role in energy metabolism and boosting NAD+ has positive effects on metabolic regulation, activation of NAMPT is an attractive therapeutic approach for the treatment of various diseases, including type 2 diabetes and obesity. Herein we report the discovery of 1-(2-phenyl-1,3-benzoxazol-6-yl)-3-(pyridin-4-ylmethyl)urea 12c (DS68702229), which was identified as a potent NAMPT activator. Compound 12c activated NAMPT, increased cellular NAD+ levels, and exhibited an excellent pharmacokinetic profile in mice after oral administration. Oral administration of compound 12c to high-fat diet-induced obese mice decreased body weight. These observations indicate that compound 12c is a promising anti-obesity drug candidate.


Subject(s)
Anti-Obesity Agents/chemical synthesis , Nicotinamide Phosphoribosyltransferase/metabolism , Small Molecule Libraries/chemical synthesis , Urea/chemical synthesis , Animals , Anti-Obesity Agents/administration & dosage , Anti-Obesity Agents/pharmacokinetics , Body Weight/drug effects , Diabetes Mellitus, Type 2/metabolism , Humans , Male , Mice, Obese , NAD/metabolism , Obesity/metabolism , Small Molecule Libraries/administration & dosage , Small Molecule Libraries/pharmacokinetics , Structure-Activity Relationship , Urea/administration & dosage , Urea/pharmacokinetics
6.
Biosci Biotechnol Biochem ; 83(8): 1514-1522, 2019 Aug.
Article in English | MEDLINE | ID: mdl-30595103

ABSTRACT

Koji, which is manufactured by proliferating non-pathogenic fungus Aspergillus oryzae on steamed rice, is the base for Japanese traditional fermented foods. We have revealed that koji and related Japanese fermented foods and drinks such as amazake, shio-koji, unfiltered sake and miso contain abundant glycosylceramide. Here, we report that feeding of koji glycosylceramide to obese mice alters the cholesterol metabolism . Liver cholesterol was significantly decreased in obese mice fed with koji glycosylceramide. We hypothesized that their liver cholesterol was decreased because it was converted to bile acids. Consistent with the hypothesis, many bile acids were increased in the cecum and feces of obese mice fed with koji glycosylceramide. Expressions of CYP7A1 and ABCG8 involved in the metabolism of cholesterol were significantly increased in the liver of mice fed with koji glycosylceramide. Therefore, it was considered that koji glycosylceramide affects the cholesterol metabolism in obese mice.


Subject(s)
Ceramides/administration & dosage , Cholesterol/metabolism , Fermented Foods , ATP Binding Cassette Transporter, Subfamily G, Member 8/metabolism , Animals , Aspergillus oryzae/metabolism , Bile Acids and Salts/metabolism , Cholesterol 7-alpha-Hydroxylase/metabolism , Japan , Lipoproteins/metabolism , Liver/metabolism , Male , Mice , Mice, Inbred C57BL , Mice, Obese
7.
Pacing Clin Electrophysiol ; 40(5): 514-515, 2017 May.
Article in English | MEDLINE | ID: mdl-28224636

ABSTRACT

BACKGROUND: The aim of the present study was to investigate the validity of the contactless vital sensing system that we previously developed. METHODS: A total of 111 healthy Japanese subjects were recruited from the University of Occupational and Environmental Health and the Panasonic Corporation AVC Networks Company. All subjects underwent an evaluation using the contactless vital sensing system and electrocardiography (ECG). We compared the R-R interval obtained using the new contactless sensing system to that obtained using ECG. RESULTS: A very strong correlation was observed between the instruments. CONCLUSIONS: This result confirms the validity of the new contactless sensing system in evaluating healthy subjects.


Subject(s)
Electrocardiography/instrumentation , Heart Rate Determination/instrumentation , Heart Rate/physiology , Radar/instrumentation , Adult , Equipment Design , Equipment Failure Analysis , Female , Humans , Male , Middle Aged , Reference Values , Reproducibility of Results , Sensitivity and Specificity , Touch , Young Adult
8.
Cancer Sci ; 107(7): 1013-7, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27089226

ABSTRACT

The RCC-SELECT study showed the correlation between single nucleotide polymorphisms (SNP) in STAT3 gene and survival in metastatic renal cell carcinoma (mRCC) patients with first-line interferon-α (IFN-α). In that study, even patients with STAT3 SNP linked to shorter overall survival (OS) exhibited remarkably improved prognosis. All 180 patients evaluated in the above study were further analyzed for correlation between OS and demographics/clinicopathological parameters. OS was estimated using the Kaplan-Meier method. Associations between OS and potential prognostic factors were assessed using the log-rank test and the Cox proportional hazards model. The median OS was 42.8 months. Univariate analysis showed that worse Eastern Cooperative Oncology Group-performance status (ECOG-PS), high T stage, regional lymph node metastasis, distant metastasis, higher grade, infiltrative growth pattern, the presence of microscopic vascular invasion (MVI), hypercalcemia, anemia, thrombocytopenia and elevated C-reactive protein were significantly associated with OS. Multivariate analysis revealed that ECOG-PS (hazard ratio [HR] = 3.665, P = 0.0004), hypercalcemia (HR = 6.428, P = 0.0005) and the presence of MVI (HR = 2.668, P = 0.0109) were jointly significant poor prognostic factors. This is the first study analysing prognostic factors of mRCC patients with first-line IFN-α using large cohort of the prospective study. The present study suggests that first-line IFN-α is still a useful therapy for mRCC even in the era of molecular targeted therapy.


Subject(s)
Antineoplastic Agents/administration & dosage , Antineoplastic Agents/therapeutic use , Carcinoma, Renal Cell/drug therapy , Interferon-alpha/administration & dosage , Interferon-alpha/therapeutic use , Kidney Neoplasms/drug therapy , Molecular Targeted Therapy , Adult , Aged , Aged, 80 and over , Carcinoma, Renal Cell/genetics , Carcinoma, Renal Cell/pathology , Case-Control Studies , Cohort Studies , Female , Humans , Kidney Neoplasms/genetics , Kidney Neoplasms/pathology , Male , Middle Aged , Neoplasm Metastasis , Polymorphism, Single Nucleotide/genetics , Prognosis , STAT3 Transcription Factor/genetics , Survival Rate , Treatment Outcome
9.
J Urol ; 195(1): 41-6, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26307162

ABSTRACT

PURPOSE: The optimal dose of intravesical bacillus Calmette-Guérin for the treatment of nonmuscle invasive bladder cancer is controversial. We investigated if induction therapy with low dose bacillus Calmette-Guérin could achieve a complete response rate similar to that of standard dose bacillus Calmette-Guérin, with less toxicity and higher quality of life. MATERIALS AND METHODS: After transurethral resection, patients with unresectable multiple nonmuscle invasive bladder cancer and/or carcinoma in situ were randomized to receive standard (80 mg) or low dose (40 mg) bacillus Calmette-Guérin instillation induction therapy (weekly, 8 times). The primary end point was noninferiority of low dose bacillus Calmette-Guérin with a null hypothesis of a 15% decrease in complete response rate. Secondary end points were recurrence-free survival, progression-free survival, overall survival, patient compliance, adverse events and quality of life using the EORTC QLQ-C30. RESULTS: In an intent to treat analysis of 166 patients the complete response rates for low dose and standard dose bacillus Calmette-Guérin were 79% (95% CI 0.70-0.88) and 85% (95% CI 0.77-0.92), respectively. Dunnett-Gent analysis revealed that the null hypothesis of inferiority of low dose bacillus Calmette-Guérin in terms of complete response could not be rejected (p = 0.119). However, there were no significant differences between the groups in terms of recurrence, progression and overall survival. Low dose bacillus Calmette-Guérin was associated with significantly less fever (p = 0.001) and micturition pain (p = 0.047), and significantly higher quality of life scores for global quality of life, role functioning and functional impairment. CONCLUSIONS: The noninferiority of low dose bacillus Calmette-Guérin was not proven. However, low dose bacillus Calmette-Guérin was associated with lower toxicity and higher quality of life compared to standard dose bacillus Calmette-Guérin in patients with nonmuscle invasive bladder cancer.


Subject(s)
Adjuvants, Immunologic/administration & dosage , BCG Vaccine/administration & dosage , Quality of Life , Urinary Bladder Neoplasms/drug therapy , Adjuvants, Immunologic/adverse effects , Administration, Intravesical , Aged , BCG Vaccine/adverse effects , Female , Humans , Male , Neoplasm Invasiveness , Treatment Outcome , Urinary Bladder Neoplasms/pathology
10.
J Am Chem Soc ; 136(46): 16444-51, 2014 Nov 19.
Article in English | MEDLINE | ID: mdl-25374117

ABSTRACT

The synthesis of QRSTUVWXYZA' domains 7, 8, and 9 of the highly potent marine neurotoxin maitotoxin (1), the largest secondary metabolite isolated to date, is described. The devised synthetic strategy entailed a cascade Takai-Utimoto ester olefination/ring closing metathesis to construct ring Y, a hydroxydithioketal cyclization/methylation sequence to cast ring X, a Horner-Wadsworth-Emmons coupling of WXYZA' ketophosphonate 11 with QRSTU aldehyde 12 to form enone 10, and a reductive hydroxyketone ring closure to forge ring V. 2D NMR spectroscopic analysis and comparison of (13)C chemical shifts with those of the corresponding carbons of maitotoxin revealed close similarities supporting the originally assigned structure of this region of the natural product. Biological evaluations of various synthesized domains of maitotoxin in this and previous studies from these laboratories led to fragment structure-activity relationships regarding their ability to inhibit maitotoxin-elicited Ca(2+) influx in rat C6 glioma cells.


Subject(s)
Marine Toxins/chemistry , Oxocins/chemistry , Peptide Fragments/chemical synthesis , Peptide Fragments/pharmacology , Aldehydes/chemistry , Amino Acid Sequence , Animals , Calcium/metabolism , Cell Line, Tumor , Chemistry Techniques, Synthetic , Humans , Marine Toxins/toxicity , Organophosphonates/chemistry , Oxocins/toxicity , Peptide Fragments/chemistry , Protein Structure, Tertiary , Rats
11.
Bioorg Med Chem ; 22(15): 4246-56, 2014 Aug 01.
Article in English | MEDLINE | ID: mdl-24909680

ABSTRACT

We report herein the synthesis and structure-activity relationships (SAR) of a series of benzyl ether compounds as an S1P1 receptor modulator. From our SAR studies, the installation of substituents onto the central benzene ring of 2a was revealed to potently influence the S1P1 and S1P3 agonistic activities, in particular, an ethyl group on the 2-position afforded satisfactory S1P1/S1P3 selectivity. These changes of the S1P1 and S1P3 agonistic activities caused by the alteration of substituents on the 2-position were reasonably explained by a docking study using an S1P1 X-ray crystal structure and S1P3 homology modeling. We found that compounds 2b and 2e had a potent in vivo immunosuppressive efficacy along with acceptable S1P1/S1P3 selectivity, and confirmed that these compounds had less in vivo bradycardia risk through the evaluation of heart rate change after oral administration of the compounds (30 mg/kg, p.o.) in rats.


Subject(s)
Ethers/chemistry , Immunosuppressive Agents/chemistry , Receptors, Lysosphingolipid/agonists , Administration, Oral , Animals , Binding Sites , Ethers/pharmacokinetics , Ethers/therapeutic use , Graft Rejection/prevention & control , Half-Life , Heart Rate/drug effects , Immunosuppressive Agents/pharmacology , Immunosuppressive Agents/therapeutic use , Male , Molecular Docking Simulation , Protein Structure, Tertiary , Rats , Rats, Inbred Lew , Receptors, Lysosphingolipid/metabolism , Structure-Activity Relationship , Transplantation, Homologous
12.
J Nutr Sci Vitaminol (Tokyo) ; 69(6): 444-453, 2023.
Article in English | MEDLINE | ID: mdl-38171817

ABSTRACT

Zinc (Zn) deficiency is one of the most common nutritional deficiencies worldwide. It is associated with reduced nutritional status and has been reported in cases of growth retardation, alopecia, and decreased serum alkaline phosphatase (ALP). It has also been reported to occur during total parenteral nutrition (TPN) administration and is associated with various diseases, such as liver diseases, diabetes, and kidney disease. We used Zn-deficient mice of ICR and C57BL/6J strains to investigate the various effects of Zn deficiency on the body, assuming that a healthy person may also become deficient in Zn either due to an unbalanced diet or malabsorption. The results showed that a Zn-deficient diet suppressed body weight gain and increased the tissue weight of the kidneys and cecum in both strains of mice. Biochemical data showed no decrease in serum ALP activity in either strain. Furthermore, in C57BL/6J mice, a Zn-deficient diet caused alopecia, loss of villi in the small intestine, and eventually affected the intestinal mucosa, which could be a risk factor for poor nutritional status. Although previous reports have shown that serum ALP activity is decreased during Zn deficiency, this is the first study that used 4-wk-old mice of ICR and C57BL/6J strains to show that serum ALP activity, which is a Zn deficiency marker, did not decrease in the two strains of Zn-deficient mice; furthermore, a Zn-deficient diet causes various symptoms.


Subject(s)
Diet , Zinc , Humans , Mice , Animals , Mice, Inbred ICR , Mice, Inbred C57BL , Alopecia
13.
Bioorg Med Chem Lett ; 22(4): 1788-92, 2012 Feb 15.
Article in English | MEDLINE | ID: mdl-22264485

ABSTRACT

S1P(3)-sparing S1P(1) agonists have attracted attention as a suppressant of autoimmunity with reduced side effects. Our synthetic efforts and extensive SAR studies led to the discovery of 10b named CS-2100 with the EC(50) value of 4.0 nM for human S1P(1) and over 5000-fold selectivity against S1P(3). The in vivo immunosuppressive efficacy was evaluated in rats on host versus graft reaction and the ID(50) value was determined at 0.407mg/kg. The docking studies of CS-2100 with the homology model of S1P(1) and S1P(3) showed that the ethyl group on the thiophene ring of CS-2100 was sterically hindered by Phe263 in S1P(3), not in the case of Leu276 in S1P(1). This observation gives an explanation for the excellent S1P(3)-sparing characteristic of CS-2100.


Subject(s)
Drug Discovery , Oxadiazoles/chemical synthesis , Receptors, Lysosphingolipid/agonists , Thiophenes/chemical synthesis , Administration, Oral , Animals , Binding, Competitive , Humans , Immune System/drug effects , Immunosuppressive Agents/chemistry , Immunosuppressive Agents/pharmacology , Inhibitory Concentration 50 , Models, Molecular , Molecular Structure , Oxadiazoles/administration & dosage , Oxadiazoles/pharmacology , Rats , Structure-Activity Relationship , Thiophenes/administration & dosage , Thiophenes/pharmacology
14.
Bioorg Med Chem Lett ; 22(9): 3083-8, 2012 May 01.
Article in English | MEDLINE | ID: mdl-22487179

ABSTRACT

We have previously disclosed 1,2,4-oxadiazole derivative 3 as a potent S1P(3)-sparing S1P(1) agonist. Although compound 3 exhibits potent and manageable immunosuppressive efficacy in various in vivo models, recent studies have revealed that its 1,2,4-oxadiazole ring is subjected to enterobacterial decomposition. As provisions for unpredictable issues, a series of alternative compounds were synthesized on the basis of compound 3. Extensive SAR studies led to the finding of 1,3-thiazole 24c with the EC(50) value of 3.4 nM for human S1P(1), and over 5800-fold selectivity against S1P(3). In rat on host versus graft reaction (HvGR), the ID(50) value of 24c was determined at 0.07 mg/kg. The pharmacokinetics in rat and monkey is also reported. Compared to compound 3, 24c showed excellent stability against enterobacteria.


Subject(s)
Pyridines/chemical synthesis , Receptors, Lysosphingolipid/agonists , Thiazoles/chemistry , Thiophenes/chemical synthesis , Animals , Haplorhini , Humans , Pyridines/pharmacology , Rats , Structure-Activity Relationship , Thiazoles/pharmacology , Thiophenes/pharmacology
15.
Tohoku J Exp Med ; 228(4): 371-6, 2012 12.
Article in English | MEDLINE | ID: mdl-23171742

ABSTRACT

Amyotrophic lateral sclerosis (ALS) is a progressive debilitating neurological disease. ALS disturbs the quality of life by affecting speech, swallowing and free mobility of the arms without affecting intellectual function. It is therefore of significance to improve intelligibility and quality of speech sounds, especially for ALS patients with slowly progressive courses. Currently, however, there is no effective or established approach to improve speech disorder caused by ALS. We investigated a surgical procedure to improve speech disorder for some patients with neuromuscular diseases with velopharyngeal closure incompetence. In this study, we performed the surgical procedure for two patients suffering from severe speech disorder caused by slowly progressing ALS. The patients suffered from speech disorder with hypernasality and imprecise and weak articulation during a 6-year course (patient 1) and a 3-year course (patient 2) of slowly progressing ALS. We narrowed bilateral lateral palatopharyngeal wall at velopharyngeal port, and performed this surgery under general anesthesia without muscle relaxant for the two patients. Postoperatively, intelligibility and quality of their speech sounds were greatly improved within one month without any speech therapy. The patients were also able to generate longer speech phrases after the surgery. Importantly, there was no serious complication during or after the surgery. In summary, we performed bilateral narrowing of lateral palatopharyngeal wall as a speech surgery for two patients suffering from severe speech disorder associated with ALS. With this technique, improved intelligibility and quality of speech can be maintained for longer duration for the patients with slowly progressing ALS.


Subject(s)
Amyotrophic Lateral Sclerosis/complications , Pharyngeal Muscles/surgery , Speech Disorders/surgery , Velopharyngeal Insufficiency/etiology , Velopharyngeal Insufficiency/surgery , Aged , Female , Humans , Male , Sound Spectrography , Speech Disorders/etiology , Speech Intelligibility/physiology , Speech Production Measurement , Treatment Outcome
16.
J Am Chem Soc ; 133(2): 220-6, 2011 Jan 19.
Article in English | MEDLINE | ID: mdl-21166430

ABSTRACT

A synthesis of the WXYZA' domain (7) of the marine neurotoxin maitotoxin (1) is reported. The convergent synthetic strategy involves construction of key building blocks 11 and 12, their coupling, and the elaboration of the resulting ester (10) to the target molecule through a ring-closing metathesis and a hydroxy dithioketal cyclization as the key steps. For the construction of fragment 11, the Noyori reduction/Achmatowicz rearrangement and hydroxy epoxide opening technologies were applied (starting from furfuryl alcohol (13)), whereas for the synthesis of fragment 12, a carbohydrate-based approach was adopted (starting from 2-deoxy-D-ribose (14)). The synthesized WXYZA' domain (7) of maitotoxin (1) exhibited the expected (13)C NMR chemical shifts, supporting the originally assigned structure of the corresponding region of the natural product.


Subject(s)
Marine Toxins/chemical synthesis , Oxocins/chemical synthesis , Marine Toxins/chemistry , Molecular Conformation , Oxocins/chemistry
17.
J Am Chem Soc ; 133(2): 214-9, 2011 Jan 19.
Article in English | MEDLINE | ID: mdl-21166429

ABSTRACT

A devised biomimetic strategy toward the C'D'E'F' domain (6) of maitotoxin (1) led to hydroxy triepoxide 8 as a postulated polyepoxide precursor. However, all attempts to induce the desired cascade to form the targeted compound through a zip-type reaction under neutral or acidic conditions failed, prompting adoption of a linear stepwise approach to 6. The successful synthetic strategy for the synthesis of the C'D'E'F' domain of maitotoxin commenced from furfuryl alcohol (11), proceeded through F' ring building block 15, and involved two regio- and stereoselective intramolecular hydroxy epoxide openings and a stereoselective SmI(2)-mediated ring closure to forge rings C', E', and D', respectively. (13)C NMR spectroscopic analysis of the synthesized domain (6) and comparisons with previous results confirmed the original structural assignment of this region of maitotoxin. X-ray crystallographic analysis of 6 provided unambiguous proof of its structure.


Subject(s)
Marine Toxins/chemical synthesis , Oxocins/chemical synthesis , Marine Toxins/chemistry , Molecular Conformation , Oxocins/chemistry
18.
Front Public Health ; 9: 731239, 2021.
Article in English | MEDLINE | ID: mdl-35071150

ABSTRACT

Indiscriminate regional lockdowns aim to prevent the coronavirus disease 2019 (COVID-19) infection by restricting the movement of people; however, this comes with psychological, social, and economic costs. Measures are needed that complement lockdowns and reduce adverse effects. Epidemiological studies, to date, have identified high-risk populations, but not workplaces appropriate for closure. This study was conducted to provide evidence-based measures that used exact and reliable follow-up data of the PCR-positive COVID-19 cases to complement lockdowns. The data are not subjected to selection or follow-up biases, since the Japanese government, by law, must register and follow all the PCR-positive cases until either recovery or death. Direct customer exposure may affect the quantity of viral inoculum received, which, in turn, may affect the risk of the severity of disease at infection. Therefore, the professions of the cases were grouped according to their frequency of direct customer exposure (FDCE) based on subjective observations, which resulted in five workplaces; hospital, school, food service, outdoor service, and indoor office being identified. Analyzing the follow-up data, we obtained precise estimates for the risk of severe disease, defined as intensive care unit (ICU) hospitalization or death, for the workplaces adjusted for age, sex, family status, and comorbidity. Major findings are as follows: hospital and school are the lowest risk, food and outdoor services are, despite higher FDCE, safer than indoor office. Unemployed and unclear are the highest risk, despite low FDCE. These results suggest the following workplace-specific measures complementing the lockdown: school should not be closed and indiscriminate closing of food and outdoor service industries should be avoided, since it would be more effective to reinforce their efforts to promote adherence to public health guidelines among students and customers. These actions would also reduce the adverse effects of the lockdown. This study is the first to address the causality between the workplaces and severe disease. We introduce FDCE and adherence to public health guidelines (APHGs) to associate the workplace characteristics with the risk of COVID-19 severity, which provided the basis for the measures complementing lockdowns.


Subject(s)
COVID-19 , Communicable Disease Control , Humans , Public Health , SARS-CoV-2 , Workplace
19.
Genes Genet Syst ; 96(3): 129-139, 2021 Oct 09.
Article in English | MEDLINE | ID: mdl-34148895

ABSTRACT

In various coastal areas of Japan, naturalized radish populations are observed. Radish is a cruciferous plant and exhibits self-incompatibility, involving a system controlled by a single locus with multiple S alleles. Although the S allele diversity of radish cultivars and wild radishes has been characterized, the S allele distribution in naturalized populations has not yet been analyzed in relation to the positions of the plants in situ. Here, we show the S allele distribution in naturalized radish populations of Yakushima, a small island in the East China Sea, with positions of the plants. Radish plants were sampled in coastal areas in Yakushima, and their S alleles were detected and characterized. Most of the S alleles had been previously identified in radish cultivars. However, four novel S alleles, which may be unique to Yakushima, were also found. Moreover, seeds in siliques from plants growing in the study areas were sampled, and S allele determination in DNA extracted from these seeds suggested that the plants had exchanged their pollen among their close neighbors. There was also a problem in that the PCR amplification of some SRK alleles was difficult because of their sequence diversity in the naturalized populations, as occurs in cultivars. Our results suggest that the exchange of S alleles between cultivars and naturalized populations occurs and that S alleles in naturalized populations are highly diverse. The methodology established in our study should be applicable to other self-incompatible species to dissect the diversity of S allele distribution in naturalized populations.


Subject(s)
Brassicaceae , Raphanus , Alleles , Brassicaceae/genetics , Japan , Pollen , Raphanus/genetics
20.
Biol Pharm Bull ; 33(9): 1500-5, 2010.
Article in English | MEDLINE | ID: mdl-20823564

ABSTRACT

A sphingosine-1-phosphate receptor 1 (S1P1) antagonist is expected to be an anti-angiogenic compound; however, there are few reports that demonstrated that a S1P1 inhibitor improved the disease state in an angiogenic animal model. Since we determined that a prototype S1P1 antagonist was an in vivo angiogenesis inhibitor, we developed the derivatives to acquire more effective compounds. In this report, we show the S1P1 antagonistic activity of some representatives, especially compound 5 {sodium 4-[(4-butoxyphenyl)thio]-2'-[{4-[(heptylthio)methyl]-2-hydroxyphenyl}(hydroxy)methyl]biphenyl-3-sulfonate}. The IC50 values calculated from an intracellular cyclic AMP measurement assay and a [33P]sphingosine-1-phosphate (Sph-1-P)/S1P1 binding assay were 38 and 200 nM, respectively. A subtype specificity test for the other Sph-1-P receptors showed that compound 5 was the S1P1-directional antagonist. It also inhibited the proliferation, migration, and tube formation of human umbilical vein endothelial cells stimulated by Sph-1-P with the IC50 values of 18, 650, and 230 nM, respectively. A cytotoxicity assay concurrently performed with a tube formation assay supported the hypothesis that these biological effects were not due to its cytotoxicity. Furthermore, administration (10 mg/kg, intravenously) to anesthetized Sprague-Dawley rats inhibited Sph-1-P-induced hypotension by 100-90% for 30 min. This is presumably through the inhibition of Sph-1-P-induced vasorelaxation, mainly by the blocking of S1P1 and/or S1P3. Taken together, these results show that compound 5 is an inhibitor of in vitro and in vivo Sph-1-P signaling, and that it will be useful to elucidate the in vivo effect of Sph-1-P on vascular endothelial cells.


Subject(s)
Cell Proliferation/drug effects , Endothelial Cells/drug effects , Lysophospholipids/antagonists & inhibitors , Receptors, Lysosphingolipid/antagonists & inhibitors , Sphingosine/analogs & derivatives , Vasodilation/drug effects , Animals , CHO Cells , Cell Movement/drug effects , Cell Movement/physiology , Cells, Cultured , Cricetinae , Cricetulus , Endothelial Cells/physiology , Humans , Lysophospholipids/pharmacology , Rats , Rats, Sprague-Dawley , Receptors, Lysosphingolipid/physiology , Sphingosine/antagonists & inhibitors , Sphingosine/pharmacology , Vasodilation/physiology
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