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1.
Eur J Immunol ; 54(4): e2350800, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38282083

ABSTRACT

Obesity-induced adipose tissue inflammation plays a critical role in the development of metabolic diseases. For example, NK1.1+ group 1 innate lymphoid cells (G1-ILCs) in adipose tissues are activated in the early stages of inflammation in response to a high-fat diet (HFD). In this study, we examined whether the composition of fatty acids affected adipose inflammatory responses induced by an HFD. Mice were fed a stearic acid (C18:0)-rich HFD (HFD-S) or a linoleic acid (C18:2)-rich HFD (HFD-L). HFD-L-fed mice showed significant obesity compared with HFD-S-fed mice. Visceral and subcutaneous fat pads were enlarged and contained more NK1.1+KLRG1+ cells, indicating that G1-ILCs were activated in HFD-L-fed mice. We examined early changes in adipose tissues during the first week of HFD intake, and found that mice fed HFD-L showed increased levels of NK1.1+CD11b+KLRG1+ cells in adipose tissues. In adipose tissue culture, addition of 4-hydroxynonenal, the most frequent product of lipid peroxidation derived from unsaturated fatty acids, induced NK1.1+CD11b+CD27- cells. We found that calreticulin, a ligand for the NK activating receptor, was induced on the surface of adipocytes after exposure to 4-hydroxynonenal or a 1-week feeding with HFD-L. Thus, excess fatty acid intake and the activation of G1-ILCs initiate and/or modify adipose inflammation.


Subject(s)
Aldehydes , Diet, High-Fat , Fatty Acids , Animals , Mice , Adipocytes , Adipose Tissue , Calreticulin/metabolism , Diet, High-Fat/adverse effects , Fatty Acids/metabolism , Immunity, Innate , Inflammation/metabolism , Lymphocytes/metabolism , Obesity
3.
Jpn J Ophthalmol ; 67(3): 353-360, 2023 May.
Article in English | MEDLINE | ID: mdl-36961660

ABSTRACT

PURPOSE: We report and verify a novel hue discrimination instrument. We also investigate its efficiency to determine hue discrimination in persons with normal color vision. STUDY DESIGN: Experimental and clinical investigation. METHOD AND STUDY PARTICIPANTS: The instrument setup comprises an optical unit and examination unit. The optical unit is composed of the same 2 spectrometers and their controllers, which enables the independent emission of different spectral lights. Two independent bundle fibers connect the optical unit and the examination unit. Two different wavelength lights are illuminated on the bipartite upper and lower circular objectives with a visual angle of 2 degrees in the examination unit. The examinee recognizes the difference in the spectral lights between the bipartite targets. Persons with normal color vision are examined and the findings are confirmed using the Ishihara Test for Colour Deficiency. RESULTS: The instrument could generate spectral light from 450 to 650 nm within 2-nm accuracy. The spectral light showed a different light intensity according to the spectral centroid, ranging from 450 to 650 nm, but the difference could be adjusted and was negligible in terms of determination of hue discrimination using the power meter. Three width slits, 0.2 mm, 0.5 mm, and 1.0 mm, to homogenize the light path were investigated. The half-width wavelength was accurate on each spectral centroid; however, the 0.5 mm slit was suitable to generate an efficient light path. The hue discrimination differed among the study participants. In general, at short and long wavelength lights, the hue discrimination range was large: about 15 nm at 450 nm and about 10 nm at 650 nm. Between 470 and 620 nm, the hue discrimination showed good sensitivity and specificity between 8 and 2 nm depending on the targeting wavelength lights. Intraindividual variation was small, ranging from 3 to 1 nm, thus indicating good repeatability. The time to examine the hue discrimination was about 20 min. CONCLUSION: This newly invented instrument using two independent spectrometer units enabled the determination of hue discrimination. The instrument's sensitivity and specificity including its repeatability were confirmed and indicated that the instrument could be a clinically applicable method.


Subject(s)
Color Perception , Light , Humans
4.
Front Microbiol ; 14: 1080369, 2023.
Article in English | MEDLINE | ID: mdl-36778852

ABSTRACT

PE_PGRS30 belongs to the PE_PGRS protein family and is characterized by a conserved Pro-Glu (PE) domain and a typically polymorphic GC-rich sequence (PGRS) domain. PE_PGRS30 is a virulence factor of Mycobacterium tuberculosis that induces macrophage cell death. We found that RAW264.7 cells and murine alveolar macrophages underwent apoptosis in response to PE_PGRS30. The host protein prohibitin 2 (PHB2) was identified as a target molecule. PE_PGRS30 and PHB2 interact via the PGRS domain and mitochondrial targeting sequence, respectively. PHB2 overexpression reduced macrophage apoptosis in response to PE_PGRS30. PE_PGRS30 co-localized with PHB2, not in mitochondria, but in lysosomes. The maintenance of mitochondrial structure by PHB2 was impaired in response to the PGRS domain. These results indicated that PE_PGRS30 reduces PHB2 in mitochondria, resulting in mitochondrial dysfunction and cellular apoptosis.

5.
Molecules ; 27(1)2021 Dec 24.
Article in English | MEDLINE | ID: mdl-35011332

ABSTRACT

Propellanes are polycyclic compounds in which tricyclic systems share one carbon-carbon single bond. Propellane frameworks that consist of larger sized rings are found in a variety of natural products. As an approach to the stereoselective synthesis of the propellane framework, one of the efficient methods is forming several rings in a single operation. Lapidilectine B (1) is composed of a propellane framework and was synthesized through the oxidative cyclization of trisubstituted alkenes. When the alkene with an ester moiety was treated with N-iodosuccinimide (NIS), iodocyclization proceeded to give the cyclic carbamate. On the other hand, when PhI(OAc)2 was allowed to react in the carboxyl form, a furoindolin-2-one structure corresponding to the A-B-C ring of lapidilectine B (1) was produced. Furthermore, when Pd(OAc)2 catalyst was used for cyclization under oxidative conditions, the product yield was improved.

6.
Cells ; 9(6)2020 06 01.
Article in English | MEDLINE | ID: mdl-32492819

ABSTRACT

To identify factors involved in the earliest phase of the differentiation of human embryonic stem cells (hESCs) into brown adipocytes (BAs), we performed multi-time point microarray analyses. We found that growth/differentiation factor 15 (GDF15) expressions were specifically upregulated within three days of differentiation, when expressions of immature hESC markers were sustained. Although GDF15 expressions continued to increase in the subsequent differentiation phases, GDF15-deficient hESCs differentiated into mature BAs (Day 10) without apparent abnormalities. In addition, GDF15-deficient mice had normal brown adipose tissue (BAT) and were metabolically healthy. Unexpectedly, we found that interleukin-6 (IL6) expression was significantly lowered in the BAT of GDF15-/- mice. In addition, GDF15-/- hESCs showed abortive IL6 expressions in the later phase (>Day 6) of the differentiation. Interestingly, GDF15 expression was markedly repressed throughout the whole course of the differentiation of IL6-/- hESCs into BAs, indicating IL6 is essential for the induction of GDF15 in the differentiation of hESCs. Finally, intraperitoneally transplanted BAT grafts of GDF15-/- donor mice, but not those of wild-type (WT) mice, failed in the long-term survival (12 weeks) in GDF15-/- recipient mice. Collectively, GDF15 is required for long-term survival of BAT grafts by creating a mutual gene induction loop with IL6.


Subject(s)
Adipose Tissue, Brown/transplantation , Growth Differentiation Factor 15/metabolism , Interleukin-6/metabolism , Tissue Survival/physiology , Adipocytes, Brown/metabolism , Animals , Cell Differentiation/genetics , Cell Line , Gene Expression Regulation , Growth Differentiation Factor 15/deficiency , Human Embryonic Stem Cells/cytology , Human Embryonic Stem Cells/metabolism , Humans , Mice, Knockout , Models, Biological
7.
Cells ; 8(4)2019 04 24.
Article in English | MEDLINE | ID: mdl-31022954

ABSTRACT

We previously established a method for a directed differentiation of human pluripotent stem cells into classical brown adipocytes (BA) by forming aggregates via massive floating culture in the presence of a specific cytokine cocktail. However, use of recombinant cytokines requires significant cost. Moreover, an enforced differentiation by exogenously added cytokines may amend skewed differentiation propensity of patient's pluripotent stem cells, providing unsatisfactory disease models. Therefore, an exogenous cytokine-free method, where cytokines required for differentiation are provided in an auto/paracrine manner mimicking natural developmental process, is beneficial. Here we show that, if human pluripotent stem cells are cultured as size-controlled spheroids (100-120 µm radius, 2000-2500 cells/spheroid) in a mutually segregated manner with half-change of the medium every other day, they differentiate into classical BA via an authentic MYF5-positive myoblast route in the absence of exogenous cytokines. Differentiated BA exerted thermogenic activity in transplanted mice in response to beta-adrenergic receptor agonist stimuli. The cytokine-free differentiation method has further advantages in exploring BATokines, BA-derived physiologically active substances. Indeed, we have found that BA produces an unknown small (<1000 Da), highly hydrophilic molecule that augments insulin secretion from pancreatic beta cells. Our upgraded technique will contribute to an advancement of stem cell study for diverse purposes.


Subject(s)
Adipocytes, Brown/cytology , Cell Differentiation/physiology , Pluripotent Stem Cells/cytology , Adipocytes, Brown/metabolism , Adipocytes, Brown/physiology , Animals , Cell Culture Techniques/methods , Cells, Cultured , Cytokines/pharmacology , Human Embryonic Stem Cells/cytology , Human Embryonic Stem Cells/metabolism , Humans , Induced Pluripotent Stem Cells/cytology , Insulin-Secreting Cells/cytology , Mice , Pluripotent Stem Cells/metabolism , Spheroids, Cellular/metabolism , Thermogenesis
8.
J Immunol ; 197(8): 3233-3244, 2016 10 15.
Article in English | MEDLINE | ID: mdl-27605010

ABSTRACT

Peroxiredoxin (PRDX)1 is an antioxidant that detoxifies hydrogen peroxide and peroxinitrite. Compared with wild-type (WT) mice, Prdx1-deficient (Prdx1-/-) mice showed increased susceptibility to Mycobacterium tuberculosis and lower levels of IFN-γ and IFN-γ-producing CD4+ T cells in the lungs after M. tuberculosis infection. IL-12 production, c-Rel induction, and p38 MAPK activation levels were lower in Prdx1-/- than in WT bone marrow-derived macrophages (BMDMs). IFN-γ-activated Prdx1-/- BMDMs did not kill M. tubercuosis effectively. NO production levels were lower, and arginase activity and arginase 1 (Arg1) expression levels were higher, in IFN-γ-activated Prdx1-/- than in WT BMDMs after M. tuberculosis infection. An arginase inhibitor, Nω-hydroxy-nor-arginine, restored antimicrobial activity and NO production in IFN-γ-activated Prdx1-/- BMDMs after M. tuberculosis infection. These results suggest that PRDX1 contributes to host defenses against M. tuberculosis PRDX1 positively regulates IL-12 production by inducing c-Rel and activating p38 MAPK, and it positively regulates NO production by suppressing Arg1 expression in macrophages infected with M. tuberculosis.


Subject(s)
Mycobacterium tuberculosis/immunology , Peroxiredoxins/immunology , Animals , Interleukin-12/biosynthesis , Mice , Mice, Inbred C57BL , Mice, Knockout , Nitric Oxide/biosynthesis , Peroxiredoxins/deficiency
9.
Infect Immun ; 84(8): 2264-2273, 2016 08.
Article in English | MEDLINE | ID: mdl-27245411

ABSTRACT

Mycobacterium tuberculosis contains a single rRNA operon that encodes targets for antituberculosis agents, including kanamycin. To date, only four mutations in the kanamycin binding sites of 16S rRNA have been reported in kanamycin-resistant clinical isolates. We hypothesized that another mutation(s) in the region may dramatically decrease M. tuberculosis viability and virulence. Here, we describe an rRNA mutation, U1406A, which was generated in vitro and confers resistance to kanamycin while highly attenuating M. tuberculosis virulence. The mutant showed decreased expression of 20% (n = 361) of mycobacterial proteins, including central metabolic enzymes, mycolic acid biosynthesis enzymes, and virulence factors such as antigen 85 complexes and ESAT-6. The mutation also induced three proteins, including KsgA (Rv1010; 16S rRNA adenine dimethyltransferase), which closely bind to the U1406A mutation site on the ribosome; these proteins were associated with ribosome maturation and translation initiation processes. The mutant showed an increase in 17S rRNA (precursor 16S rRNA) and a decrease in the ratio of 30S subunits to the 70S ribosomes, suggesting that the U1406A mutation in 16S rRNA attenuated M. tuberculosis virulence by affecting these processes.


Subject(s)
Mutation , Mycobacterium tuberculosis/genetics , Mycobacterium tuberculosis/pathogenicity , RNA, Ribosomal, 16S/genetics , Virulence Factors/genetics , Animals , Antitubercular Agents/pharmacology , Base Sequence , Drug Resistance, Bacterial , Genetic Complementation Test , Mice , Microbial Sensitivity Tests , Microbial Viability/genetics , Mycobacterium tuberculosis/drug effects , Nucleic Acid Conformation , Proteomics/methods , RNA, Ribosomal, 16S/chemistry , Tuberculosis/genetics , Tuberculosis/metabolism , Tuberculosis/microbiology , Virulence/genetics
10.
Tuberculosis (Edinb) ; 95(3): 246-50, 2015 May.
Article in English | MEDLINE | ID: mdl-25846955

ABSTRACT

MicroRNAs (miRNAs) are short, conserved, non-coding RNA molecules that repress translation, followed by the decay of miRNA-targeted mRNAs that encode molecules involved in cell differentiation, development, immunity and apoptosis. At least six miRNAs, including microRNA-155 (miR-155), were up-regulated when born marrow-derived macrophages from C57BL/6 mice were infected with Mycobacterium tuberculosis Erdman. C57BL/6 mice intravenously infected with Erdman showed up-regulation of miR-155 in livers and lungs. Following infection, miR-155-deficient C57BL/6 mice died significantly earlier and had significantly higher numbers of CFU in lungs than wild-type mice. Moreover, fewer CD4(+) T cells, but higher numbers of monocytes and neutrophils, were present in the lungs of Erdman-infected miR-155 knockout (miR-155(-/-)) than of wild-type mice. These findings indicated that miR-155 plays a critical role in immune responses to M. tuberculosis.


Subject(s)
Lung/microbiology , MicroRNAs/genetics , Mycobacterium tuberculosis/pathogenicity , Tuberculosis, Pulmonary/genetics , Tuberculosis, Pulmonary/microbiology , Animals , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/microbiology , Cytokines/blood , Disease Models, Animal , Genetic Predisposition to Disease , Liver/metabolism , Lung/immunology , Lung/metabolism , Male , Mice, Inbred C57BL , Mice, Knockout , MicroRNAs/metabolism , Monocytes/immunology , Monocytes/microbiology , Mycobacterium tuberculosis/immunology , Neutrophils/immunology , Neutrophils/microbiology , Phenotype , Time Factors , Tuberculosis, Pulmonary/blood , Tuberculosis, Pulmonary/immunology
11.
Tuberculosis (Edinb) ; 95(1): 37-9, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25458614

ABSTRACT

We report the completely annotated genome sequence of Mycobacterium tuberculosis (Zopf) Lehmann and Neumann (ATCC35812) (Kurono), which is a used for virulence and/or immunization studies. The complete genome sequence of M. tuberculosis Kurono was determined with a length of 4,415,078 bp and a G+C content of 65.60%. The chromosome was shown to contain a total of 4,340 protein-coding genes, 53 tRNA genes, one transfer messenger RNA for all amino acids, and 1 rrn operon. Lineage analysis based on large sequence polymorphisms indicated that M. tuberculosis Kurono belongs to the Euro-American lineage (lineage 4). Phylogenetic analysis using whole genome sequences of M. tuberculosis Kurono in addition to 22 M. tuberculosis complex strains indicated that H37Rv is the closest relative of Kurono based on the results of phylogenetic analysis. These findings provide a basis for research using M. tuberculosis Kurono, especially in animal models.


Subject(s)
Genome, Bacterial/genetics , Mycobacterium tuberculosis/genetics , Genes, Bacterial/genetics , Hydrolases/genetics , Phylogeny , Polymorphism, Genetic , Small Molecule Libraries
12.
Rinsho Byori ; 62(11): 1031-9, 2014 Nov.
Article in Japanese | MEDLINE | ID: mdl-27509717

ABSTRACT

Nodular gastritis is characterized histologically by hyperplasia and enlargement of lymphoid follicles in the lamina propria. With the objective of elucidating the relationship between different endoscopic types of nodular gastritis and lymphoid follicles, distributions of lymphoid follicles in the lamina propria were investigated in young gastric cancer patients with nodular gastritis. For the study, whole-mucosal step sectioning of each resected stomach was performed, the densities of lymphoid follicles of all specimens were measured microscopically, and the horizontal and depth distributions were calculated. For assessment in the horizontal direction, density distribution diagrams of lymphoid follicles were created. For assessment in the depth direction, the different endoscopic types of nodular gastritis were compared in the five different analysis sites. In the assessment of the horizontal distribution, no characteristic distribution tendencies were observed in either the granular type group or the scattered type group; however, it was found that areas with relatively high densities of lymphoid follicles generally coincided with the areas where nodular gastritis was observed endoscopically. These results suggested that hyperplasia and aggregation of lymphoid follicles in the lamina propria are involved at the sites where nodular gastritis is observed endoscopically. In the assessment of the depth distribution, lymphoid follicles tended to be more unevenly distributed in the upper lamina propria in the granular type group than in the scattered type at the three different analysis sites where nodular gastritis was observed endoscopically. These results suggested the possibility of a granular type characteristic.


Subject(s)
Gastric Mucosa/pathology , Gastritis/complications , Gastritis/pathology , Gastroscopy , Lymphoid Tissue/pathology , Adult , Female , Gastritis/classification , Gastritis/microbiology , Helicobacter Infections , Helicobacter pylori , Humans , Hyperplasia , Male , Stomach Neoplasms/complications , Stomach Neoplasms/pathology
13.
Biol Pharm Bull ; 35(7): 1132-6, 2012.
Article in English | MEDLINE | ID: mdl-22791162

ABSTRACT

In allogeneic bone marrow transplantation (allo-BMT) in patients with leukemia, the combination of VP-16 and cyclophosphamide (CY) is commonly used for the conditioning regimen. In the present study, we demonstrated schedule-dependent cytotoxicity of VP-16 and CY in K-562 cells. K-562 cells were pretreated with low concentrations (2.5 and 5 µg/mL) of 4-hydroperoxycyclophosphamide (40487S), which is a preactivated analog of CY. It was confirmed that these concentrations did not influence cell viability. Cells subsequently exposed to 0.5-100 µg/mL of VP-16 showed reduced the viability compared to that of control cells not treated with 40487S. In contrast, there was no change in the viability of K-562 cells pretreated with low concentrations (0.5 and 1 µg/mL) of VP-16. It was confirmed that these concentrations did not influence cell viability. Viability of subsequently exposed to 1-20 µg/mL was not different from that of control cells not treated with VP-16. VP-16 caused cell cycle arrest at G2/M phase. On the other hand, 40487S arrested the cell cycle at S phase. Thymidine-synchronized cells, VP-16 showed cell cycle specificity for cell killing from early-S to mid-S phase. On the other hand, 40487S showed cell cycle-independent cytotoxicity. Exposure of cells to VP-16 after 40487S induced a greater cytotoxic effect on K-562 cells. The findings may lead to improvements in clinical combination chemotherapy.


Subject(s)
Antineoplastic Agents, Alkylating/administration & dosage , Antineoplastic Agents, Phytogenic/administration & dosage , Cyclophosphamide/administration & dosage , Etoposide/administration & dosage , Cell Cycle/drug effects , Cell Survival/drug effects , Drug Administration Schedule , Humans , K562 Cells , Leukemia
14.
J Bacteriol ; 194(10): 2770, 2012 May.
Article in English | MEDLINE | ID: mdl-22535945

ABSTRACT

We report the completely annotated genome sequence of Mycobacterium tuberculosis Erdman (TMC 107; ATCC 35801), which is a well-known laboratory strain of M. tuberculosis.


Subject(s)
Genome, Bacterial , Mycobacterium tuberculosis/classification , Mycobacterium tuberculosis/genetics , Chromosomes, Bacterial , Molecular Sequence Data , Mycobacterium tuberculosis/pathogenicity , Virulence
15.
J Bacteriol ; 193(23): 6792, 2011 Dec.
Article in English | MEDLINE | ID: mdl-22072647

ABSTRACT

We report the annotated genome sequence of a clinical isolate, Mycobacterium tuberculosis strain NCGM2209, which belongs to the "Beijing family" and was isolated in Japan.


Subject(s)
Genome, Bacterial , Mycobacterium tuberculosis/genetics , Mycobacterium tuberculosis/isolation & purification , Tuberculosis/microbiology , Base Sequence , Humans , Male , Molecular Sequence Data , Mycobacterium tuberculosis/classification , Phylogeny , Young Adult
16.
J Nanobiotechnology ; 8: 23, 2010 Sep 25.
Article in English | MEDLINE | ID: mdl-20868509

ABSTRACT

Regulation of cell cycle progression in changing environments is vital for cell survival and maintenance, and different regulation mechanisms based on cell size and cell cycle time have been proposed. To determine the mechanism of cell cycle regulation in the unicellular green algae Chlamydomonas reinhardtii, we developed an on-chip single-cell cultivation system that allows for the strict control of the extracellular environment. We divided the Chlamydomonas cell cycle into interdivision and division phases on the basis of changes in cell size and found that, regardless of the amount of photosynthetically active radiation (PAR) and the extent of illumination, the length of the interdivision phase was inversely proportional to the rate of increase of cell volume. Their product remains constant indicating the existence of an 'interdivision timer'. The length of the division phase, in contrast, remained nearly constant. Cells cultivated under light-dark-light conditions did not divide unless they had grown to twice their initial volume during the first light period. This indicates the existence of a 'commitment sizer'. The ratio of the cell volume at the beginning of the division phase to the initial cell volume determined the number of daughter cells, indicating the existence of a 'mitotic sizer'.

17.
J Nanobiotechnology ; 4: 7, 2006 Aug 16.
Article in English | MEDLINE | ID: mdl-16914039

ABSTRACT

To understand the control mechanism of innate immune response in macrophages, a series of phagocytic responses to plural stimulation of antigens on identical cells was observed. Two zymosan particles, which were used as antigens, were put on different surfaces of a macrophage using optical tweezers in an on-chip single-cell cultivation system, which maintains isolated conditions of each macrophage during their cultivation. When the two zymosan particles were attached to the macrophage simultaneously, the macrophage responded and phagocytosed both of the antigens simultaneously. In contrast, when the second antigen was attached to the surface after the first phagocytosis had started, the macrophage did not respond to the second stimulation during the first phagocytosis; the second phagocytosis started only after the first process had finished. These results indicate that (i) phagocytosis in a macrophage is not an independent process when there are plural stimulations; (ii) the response of the macrophage to the second stimulation is related to the time" delay from the first stimulation. Stimulations that occur at short time intervals resulted in simultaneous phagocytosis, while a second stimulation that is delayed long enough might be neglected until the completion of the first phagocytic process.

18.
Biochem Biophys Res Commun ; 306(4): 1042-9, 2003 Jul 11.
Article in English | MEDLINE | ID: mdl-12821148

ABSTRACT

To estimate the role that time and size had in controlling the Chlamydomonas cell cycle, we used a new on-chip single-cell microcultivation system, which involved the direct observation of single cells captured in microchambers made on a thin glass slide. The dependence of the pattern of energy supply for cells on its cell cycle was examined through a series of different intensities of continuous illumination in a minimal medium, and we found that cell division occurred when cells reached the critical size, which was 2.2 times larger than that of the newly created cells. When illumination stopped before cells reached the critical size, even though growth had stopped, they continued dividing during the delay time, which was shorter when cells were larger. With re-illumination after darkness, cells began to grow again and the timing of cell division was again controlled by the critical size. This indicates that the co-existence of two cell cycle regulation mechanisms and the sizer mechanism had a stronger influence than the timer.


Subject(s)
Cell Culture Techniques/instrumentation , Cell Culture Techniques/methods , Chlamydomonas reinhardtii/physiology , Animals , Cell Cycle , Cell Division , Equipment Design , Light , Time Factors
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