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1.
Biomed Pharmacother ; 175: 116770, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38772154

ABSTRACT

Patients with inflammatory bowel diseases (IBDs), including ulcerative colitis (UC) and Crohn's disease (CD), often have concomitant mental disorders such as depression and anxiety. Therefore, a bidirectional approach involving the gut and brain axes is necessary for the prevention and treatment thereof. In this study, we explored the potential of Poncirus trifoliata extract (PT), traditionally known for its neuroprotective effects against gastrointestinal diseases, as a natural treatment agent for IBD in a dextran sulfate sodium (DSS)-induced colitis model. Oral administration of PT ameliorated weight loss and inflammatory responses in mice with DSS-induced colitis. Furthermore, PT treatment effectively restored the colon length and ameliorated enterocyte death by inhibiting DSS-induced reactive oxygen species (ROS)-mediated necroptosis. The main bioactive components of PT, poncirin and naringin, confirmed using ultra-performance liquid chromatography-quadrupole time-of-flight (UPLC-qTOF), can be utilized to regulate necroptosis. The antidepressant-like effects of PT were confirmed using open field test (OFT) and tail suspension test (TST). PT treatment also restored vascular endothelial cell integrity in the hippocampus. In the Cornu Ammonis 1 (CA1) and dentate gyrus (DG) regions of the hippocampus, PT controlled the neuroinflammatory responses of proliferated microglia. In conclusion, PT, which contains high levels of poncirin and naringin, has potential as a bidirectional therapeutic agent that can simultaneously improve IBD-associated intestinal and mental disorders.


Subject(s)
Colitis , Depression , Dextran Sulfate , Flavanones , Mice, Inbred C57BL , Plant Extracts , Poncirus , Animals , Poncirus/chemistry , Plant Extracts/pharmacology , Plant Extracts/isolation & purification , Male , Mice , Depression/drug therapy , Flavanones/pharmacology , Flavanones/isolation & purification , Colitis/drug therapy , Colitis/chemically induced , Colitis/pathology , Behavior, Animal/drug effects , Disease Models, Animal , Antidepressive Agents/pharmacology , Antidepressive Agents/isolation & purification , Flavonoids/pharmacology , Flavonoids/isolation & purification , Hippocampus/drug effects , Hippocampus/metabolism , Hippocampus/pathology , Reactive Oxygen Species/metabolism
2.
Antioxidants (Basel) ; 13(3)2024 Mar 12.
Article in English | MEDLINE | ID: mdl-38539873

ABSTRACT

Developing new plant varieties plays a crucial role in competitiveness in the agricultural and food industries and enhancing food security. Daehong (DH) is a new variety of Crataegus pinnatifida Bunge (CP); however, its physiological functions and potential as a nutraceutical ingredient remain unknown. Here, the efficacy of DH on inflammatory bowel disease (IBD) was investigated using dextran sulfate sodium (DSS)-induced colitis mice, and its relative pharmacological effects were analyzed against CP. DH improved colitis-induced weight loss, colon shortening, and inflammatory responses and reduced intestinal permeability. The reactive oxygen species (ROS)-mediated necroptotic signal that triggers enterocyte cell death in DSS-induced colitis was effectively controlled by DH, attributed to epicatechin. DSS-induced gut dysbiosis was recovered into a healthy gut microbiome environment by DH, increasing beneficial bacteria, like Akkermansia muciniphila, and changing harmful bacteria, including Bacteroides vulgatus and Peptostreptococcaceae. DH shows potential as a dietary or pharmaceutical ingredient to promote gut health and to prevent and treat IBD.

3.
Antioxidants (Basel) ; 11(12)2022 Dec 09.
Article in English | MEDLINE | ID: mdl-36552643

ABSTRACT

Necroptosis is a form of programmed cell death with features of necrosis and apoptosis that occurs in the intestinal epithelium of patients with inflammatory bowel disease (IBD), including ulcerative colitis and Crohn's disease. In addition, necroptosis has also been observed in enterocytes in animal models of dextran sulfate sodium (DSS)-induced colitis. Thus, the discovery of natural products for regulating necroptosis may represent an important therapeutic strategy for improving IBD. We found that Magnolia officinalis bark extract (MBE) prevented weight loss and suppressed the activation of the proinflammatory cytokine IL6 in DSS-induced colitis. Furthermore, MBE restored the length of the damaged colon and decreased the expression of necroptosis markers in mice with DSS-induced colitis. In vitro, necroptosis-induced reactive oxygen species (ROS) production was reduced by MBE, and the expression of COX2, a target protein of ROS, was simultaneously suppressed. Both magnolol and honokiol, the two major bioactive compounds in MBE, inhibited necroptosis in human primary intestinal epithelial cells and colorectal adenocarcinoma cells. Our findings highlight the effectiveness of MBE in modulating enterocyte necroptosis and suggest that MBE may be developed as a natural, disease-targeting drug for the treatment of colitis.

4.
Sensors (Basel) ; 22(19)2022 Sep 28.
Article in English | MEDLINE | ID: mdl-36236486

ABSTRACT

Flexible capacitive pressure sensors with a simple structure and low power consumption are attracting attention, owing to their wide range of applications in wearable electronic devices. However, it is difficult to manufacture pressure sensors with high sensitivity, wide detection range, and low detection limits. We developed a highly sensitive and flexible capacitive pressure sensor based on the porous Ecoflex, which has an aligned airgap structure and can be manufactured by simply using a mold and a micro-needle. The existence of precisely aligned airgap structures significantly improved the sensor sensitivity compared to other dielectric structures without airgaps. The proposed capacitive pressure sensor with an alignment airgap structure supports a wide range of working pressures (20-100 kPa), quick response time (≈100 ms), high operational stability, and low-pressure detection limit (20 Pa). Moreover, we also studied the application of pulse wave monitoring in wearable sensors, exhibiting excellent performance in wearable devices that detect pulse waves before and after exercise. The proposed pressure sensor is applicable in electronic skin and wearable medical assistive devices owing to its excellent functional features.


Subject(s)
Wearable Electronic Devices , Monitoring, Physiologic , Porosity , Pressure
5.
Stem Cells ; 40(9): 870-882, 2022 09 26.
Article in English | MEDLINE | ID: mdl-35852488

ABSTRACT

Allogeneic mesenchymal stem/stromal cells (MSCs) are frequently used in clinical trials due to their low expression of major histocompatibility complex (MHC) class I and lack of MHC class II. However, the levels of MHC classes I and II in MSCs are increased by inflammatory stimuli, raising concerns over potential adverse effects associated with allogeneic cell therapy. Also, it is unclear how the host immune response to MHC-mismatched MSCs affects the therapeutic efficacy of the cells. Herein, using strategies to manipulate MHC genes in human bone marrow-derived MSCs via the CRISPR-Cas9 system, plasmids, or siRNAs, we found that inhibition of MHC class I-not MHC class II-in MSCs lowered the survival rate of MSCs and their immunosuppressive potency in mice with experimental autoimmune uveoretinitis, specifically by increasing MSC vulnerability to natural killer (NK)-cell-mediated cytotoxicity. A subsequent survey of MSC batches derived from 6 human donors confirmed a significant correlation between MSC survival rate and susceptibility to NK cells with the potency of MSCs to increase MHC class I level upon stimulation. Our overall results demonstrate that MHC class I enables MSCs to evade NK-cell-mediated cytotoxicity and exert immunosuppressive activity.


Subject(s)
Mesenchymal Stem Cells , Animals , HLA Antigens , Histocompatibility Antigens Class II/genetics , Histocompatibility Antigens Class II/pharmacology , Humans , Killer Cells, Natural , Mice
7.
Pharmaceuticals (Basel) ; 15(4)2022 Mar 23.
Article in English | MEDLINE | ID: mdl-35455387

ABSTRACT

Muscle atrophy in postmenopausal women is caused by estrogen deficiency and a variety of inflammatory factors, including tumor necrosis factor alpha (TNFα). Paeoniflorin (PNF), a natural compound with anti-inflammatory properties, improves estradiol synthesis. Here, we demonstrate that PNF inhibits the progression of TNFα-induced skeletal muscle atrophy after menopause by restoring mitochondrial biosynthesis. Differentiated myoblasts damaged by TNFα were restored by PNF, as evident by the increase in the expression of myogenin (MyoG) and myosin heavy chain 3 (Myh3)-the markers of muscle differentiation. Moreover, diameter of atrophied myotubes was restored by PNF treatment. TNFα-repressed nuclear respiratory factor 1 (NRF1) and mitochondrial transcription factor A (TFAM) (a major regulator of mitochondrial biosynthesis) were restored by PNF, via regulation by estrogen receptor alpha (ERα), an upregulator of NRF1. This mechanism was confirmed in ovariectomized (OVX) mice with a ~40% reduction in the cross-sectional area of the anterior tibialis muscle. OVX mice administered PNF (100, 300 mg/kg/day) for 12 weeks recovered more than ~20%. Behavioral, rotarod, and inverted screen tests showed that PNF enhances reduced muscle function in OVX mice. ERα restored expression of mitofusin 1 (MFN1) and mitofusin 2 (MFN2) (mitochondrial fusion markers) and dynamin-related protein (DRP1) and fission 1 (FIS1) (mitochondrial fission markers). Therefore, PNF can prevent muscle atrophy in postmenopausal women by inhibiting dysfunctional mitochondrial biogenesis.

8.
NPJ Regen Med ; 7(1): 8, 2022 Jan 19.
Article in English | MEDLINE | ID: mdl-35046408

ABSTRACT

Huntington's disease (HD) is a severe inherited neurological disorder caused by a CAG repeat expansion in the huntingtin gene (HTT), leading to the accumulation of mutant huntingtin with polyglutamine repeats. Despite its severity, there is no cure for this debilitating disease. HTT lowering strategies, including antisense oligonucleotides (ASO) showed promising results very recently. Attempts to develop stem cell-based therapeutics have shown efficacy in preclinical HD models. Using an HD patient's autologous cells, which have genetic defects, may hamper therapeutic efficacy due to mutant HTT. Pretreating these cells to reduce mutant HTT expression and transcription may improve the transplanted cells' therapeutic efficacy. To investigate this, we targeted the SUPT4H1 gene that selectively supports the transcription of long trinucleotide repeats. Transplanting SUPT4H1-edited HD-induced pluripotent stem cell-derived neural precursor cells (iPSC-NPCs) into the YAC128 HD transgenic mouse model improved motor function compared to unedited HD iPSC-NPCs. Immunohistochemical analysis revealed reduced mutant HTT expression without compensating wild-type HTT expression. Further, SUPT4H1 editing increased neuronal and decreased reactive astrocyte differentiation in HD iPSC-NPCs compared to the unedited HD iPSC-NPCs. This suggests that ex vivo editing of SUPT4H1 can reduce mutant HTT expression and provide a therapeutic gene editing strategy for autologous stem cell transplantation in HD.

9.
Biomolecules ; 11(9)2021 09 03.
Article in English | MEDLINE | ID: mdl-34572519

ABSTRACT

The widely administered tuberculosis (TB) vaccine, Bacillus Calmette-Guerin (BCG), is the only licensed vaccine, but has highly variable efficiency against childhood and pulmonary TB. Therefore, the BCG prime-boost strategy is a rational solution for the development of new TB vaccines. Studies have shown that Mycobacterium tuberculosis (Mtb) culture filtrates contain proteins that have promising vaccine potential. In this study, Rv1876 bacterioferritin was identified from the culture filtrate fraction with strong immunoreactivity. Its immunobiological potential has not been reported previously. We found that recombinant Rv1876 protein induced dendritic cells' (DCs) maturation by MAPK and NF-κB signaling activation, induced a T helper type 1 cell-immune response, and expanded the population of the effector/memory T cell. Boosting BCG with Rv1876 protein enhanced the BCG-primed Th1 immune response and reduced the bacterial load in the lung compared to those of BCG alone. Thus, Rv1876 is a good target for the prime-boost strategy.


Subject(s)
Bacterial Proteins/immunology , Dendritic Cells/immunology , Immunity , Mycobacterium bovis/immunology , Th1 Cells/immunology , Animals , Antigens, Bacterial/immunology , Bacterial Proteins/genetics , Cell Proliferation , Cytokines/metabolism , Female , Immunologic Memory , Lymphocyte Activation/immunology , Mice, Inbred C57BL , Mutation/genetics , Mycobacterium bovis/growth & development , Vaccination
10.
Int J Mol Sci ; 22(14)2021 Jul 14.
Article in English | MEDLINE | ID: mdl-34299161

ABSTRACT

Prostaglandin E2 (PGE2) is an important biological mediator involved in the defense against Mycobacterium tuberculosis (Mtb) infection. Currently, there are no reports on the mycobacterial components that regulate PGE2 production. Previously, we have reported that RpfE-treated dendritic cells (DCs) effectively expanded the Th1 and Th17 cell responses simultaneously; however, the mechanism underlying Th1 and Th17 cell differentiation is unclear. Here, we show that PGE2 produced by RpfE-activated DCs via the MAPK and cyclooxygenase 2 signaling pathways induces Th1 and Th17 cell responses mainly via the EP4 receptor. Furthermore, mice administered intranasally with PGE2 displayed RpfE-induced antigen-specific Th1 and Th17 responses with a significant reduction in bacterial load in the lungs. Furthermore, the addition of optimal PGE2 amount to IL-2-IL-6-IL-23p19-IL-1ß was essential for promoting differentiation into Th1/Th17 cells with strong bactericidal activity. These results suggest that RpfE-matured DCs produce PGE2 that induces Th1 and Th17 cell differentiation with potent anti-mycobacterial activity.


Subject(s)
Bacterial Proteins/metabolism , Cell Differentiation , Dendritic Cells/metabolism , Dinoprostone/metabolism , Mycobacterium tuberculosis/physiology , Th1 Cells/cytology , Th17 Cells/cytology , Animals , Dendritic Cells/immunology , Dendritic Cells/microbiology , Female , Mice , Mice, Inbred C57BL , Signal Transduction , Th1 Cells/immunology , Th17 Cells/immunology , Tuberculosis/immunology , Tuberculosis/metabolism , Tuberculosis/microbiology
11.
Front Immunol ; 12: 666293, 2021.
Article in English | MEDLINE | ID: mdl-34017340

ABSTRACT

Although Mycobacterium tuberculosis (Mtb) is an intracellular pathogen in phagocytic cells, the factors and mechanisms by which they invade and persist in host cells are still not well understood. Characterization of the bacterial proteins modulating macrophage function is essential for understanding tuberculosis pathogenesis and bacterial virulence. Here we investigated the pathogenic role of the Rv2145c protein in stimulating IL-10 production. We first found that recombinant Rv2145c stimulated bone marrow-derived macrophages (BMDMs) to secrete IL-10, IL-6 and TNF-α but not IL-12p70 and to increase the expression of surface molecules through the MAPK, NF-κB, and TLR4 pathways and enhanced STAT3 activation and the expression of IL-10 receptor in Mtb-infected BMDMs. Rv2145c significantly enhanced intracellular Mtb growth in BMDMs compared with that in untreated cells, which was abrogated by STAT3 inhibition and IL-10 receptor (IL-10R) blockade. Expression of Rv2145c in Mycobacterium smegmatis (M. smegmatis) led to STAT3-dependent IL-10 production and enhancement of intracellular growth in BMDMs. Furthermore, the clearance of Rv2145c-expressing M. smegmatis in the lungs and spleens of mice was delayed, and these effects were abrogated by administration of anti-IL-10R antibodies. Finally, all mice infected with Rv2145c-expressing M. smegmatis died, but those infected with the vector control strain did not. Our data suggest that Rv2145c plays a role in creating a favorable environment for bacterial survival by modulating host signals.


Subject(s)
Bacterial Proteins/immunology , Mycobacterium tuberculosis/pathogenicity , Receptors, Interleukin-10/metabolism , STAT3 Transcription Factor/metabolism , Animals , Bacterial Proteins/genetics , Interleukin-10/metabolism , Macrophage Activation , Macrophages/immunology , Macrophages/microbiology , Mice , Microbial Viability/genetics , Mycobacterium smegmatis/genetics , Mycobacterium smegmatis/growth & development , Mycobacterium smegmatis/immunology , Mycobacterium smegmatis/pathogenicity , Mycobacterium tuberculosis/genetics , Mycobacterium tuberculosis/growth & development , Mycobacterium tuberculosis/immunology , Receptors, Interleukin-10/antagonists & inhibitors , Recombinant Proteins/genetics , Recombinant Proteins/immunology , STAT3 Transcription Factor/antagonists & inhibitors , Signal Transduction , Toll-Like Receptor 4/metabolism , Virulence
12.
Microbiol Immunol ; 65(4): 178-188, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33565648

ABSTRACT

Mycobacterium tuberculosis contains diverse immunologically active components. This study investigated the biological function of a newly identified component, Rv1654, with the potential to induce apoptosis in macrophages. Recombinant Rv1654 induced macrophage apoptosis in a caspase-9/3-dependent manner through the production of reactive oxygen species (ROS) and interaction with Toll-like receptor 4. In addition, Rv1654 induced the production of tumor necrosis factor-α, interleukin-6, and monocyte chemoattractant protein-1 through the mitogen-activated protein kinase pathway. Furthermore, Rv1654-induced c-Jun N-terminal kinase (JNK) activation was inhibited by the ROS scavenger and Rv1654-induced apoptosis was inhibited by the JNK inhibitor. Moreover, it was found that treatment of macrophages with Rv1654 led to the loss of mitochondrial membrane potential, release of cytochrome c into the cytosol, and translocation of Bax into the mitochondria. Finally, Rv1654-mediated apoptosis was inhibited in macrophages transfected with Bax siRNA. These results suggest that Rv1654 induces macrophage apoptosis through a mitochondrial-dependent pathway and ROS-mediated JNK activation.


Subject(s)
Apoptosis , Bacterial Proteins/immunology , Macrophages/microbiology , Mitochondria , Mycobacterium tuberculosis , Caspases , JNK Mitogen-Activated Protein Kinases/metabolism , Macrophages/metabolism , Reactive Oxygen Species/metabolism , Recombinant Proteins/immunology , Toll-Like Receptors
13.
Stem Cell Rev Rep ; 17(3): 1053-1067, 2021 06.
Article in English | MEDLINE | ID: mdl-33423156

ABSTRACT

Human embryonic stem cells (hESCs) hold promise in regenerative medicine but allogeneic immune rejections caused by highly polymorphic human leukocyte antigens (HLAs) remain a barrier to their clinical applications. Here, we used a CRISPR/Cas9-mediated HLA-editing strategy to generate a variety of HLA homozygous-like hESC lines from pre-established hESC lines. We edited four pre-established HLA-heterozygous hESC lines and created a mini library of 14 HLA-edited hESC lines in which single HLA-A and HLA-B alleles and both HLA-DR alleles are disrupted. The HLA-edited hESC derivatives elicited both low T cell- and low NK cell-mediated immune responses. Our library would cover about 40% of the Asian-Pacific population. We estimate that HLA-editing of only 19 pre-established hESC lines would give rise to 46 different hESC lines to cover 90% of the Asian-Pacific population. This study offers an opportunity to generate an off-the-shelf HLA-compatible hESC bank, available for immune-compatible cell transplantation, without embryo destruction. Graphical Abstract.


Subject(s)
Gene Editing , Human Embryonic Stem Cells , Embryo, Mammalian , Hematopoietic Stem Cell Transplantation , Humans , Regenerative Medicine
14.
Vaccines (Basel) ; 8(3)2020 Jul 10.
Article in English | MEDLINE | ID: mdl-32664238

ABSTRACT

Immunotherapy represents a promising approach for improving current antibiotic treatments through the engagement of the host's immune system. Latency-associated antigens have been included as components of multistage subunit tuberculosis vaccines. We first identified Rv2005c, a DosR regulon-encoded protein, as a seroreactive protein. In this study, we found that Rv2005c induced dendritic cell (DC) maturation and Th1 responses, and its expression by Mycobacterium tuberculosis (Mtb) within macrophages was enhanced by treatment with CoCl2, a hypoxia-mimetic agent. T cells activated by Rv2005c-matured DCs induced antimycobacterial activity in macrophages under hypoxic conditions but not under normoxic conditions. However, Rv2005c alone did not exhibit any significant vaccine efficacy in our mouse model. The fusion of Rv2005c to the macrophage-activating protein Rv2882c resulted in significant activation of DCs and antimycobacterial activity in macrophages, which were enhanced under hypoxic conditions. Furthermore, the Rv2882c-Rv2005c fusion protein showed significant adjunctive immunotherapeutic effects and led to the generation of long-lasting, antigen-specific, multifunctional CD4+ T cells that coproduced TNF-α, IFN-γ and IL-2 in the lungs of our established mouse model. Overall, these results provide a novel fusion protein with immunotherapeutic potential as adjunctive chemotherapy for tuberculosis.

15.
Cell Immunol ; 354: 104145, 2020 08.
Article in English | MEDLINE | ID: mdl-32569876

ABSTRACT

Mycobacterium tuberculosis (Mtb) is an intracellular pathogen known to persist in host cells. The apoptotic response of macrophages serves as a defense mechanism to inhibit the growth of intracellular bacteria, the failure of which can favor the spread of the pathogen to new cells. However, the mycobacterial components that regulate cell death and the related underlying mechanisms remain poorly understood. In this study, we investigated protein Rv3261, isolated from an Mtb culture filtrate, for its apoptotic potential using multidimensional fractionation. Rv3261 was found to induce macrophage apoptosis through the caspase-3/-9-dependent pathway. Furthermore, the ROS-dependent JNK activation pathway was found to be critical in Rv3261-mediated apoptosis. Rv3261 inhibited the growth of intracellular Mtb, which was significantly abrogated by pre-treatment with the ROS scavenger N-acetylcysteine (NAC), suggesting that Rv3261-mediated apoptosis may act as a host defense response. These findings suggest that Rv3261 is involved in the apoptotic modulation of Mtb-infected macrophages.


Subject(s)
Bacterial Proteins/metabolism , Macrophages/microbiology , Mitochondria/metabolism , Mycobacterium tuberculosis/physiology , Acetylcysteine/pharmacology , Animals , Apoptosis , Caspase 3/metabolism , Caspase 9/metabolism , Cell Growth Processes , Immune Evasion , Immunity, Innate , Intracellular Space , MAP Kinase Kinase 4/metabolism , Macrophages/immunology , Mice , RAW 264.7 Cells , Reactive Oxygen Species/metabolism , Signal Transduction
16.
Sci Rep ; 9(1): 4246, 2019 03 12.
Article in English | MEDLINE | ID: mdl-30862819

ABSTRACT

Macrophages are responsible for innate and adaptive immune response activation necessary for eliminating infections. Optimal activation of macrophages to phagocytize Mycobacterium tuberculosis is critical in anti-mycobacterial defense. Here, we identified a novel Rv3463 hypothetical protein that induces macrophage activation in Mtb culture filtrate. Recombinant Rv3463 activated mouse bone marrow-derived macrophages to induce the expression of surface molecules and secrete pro-inflammatory cytokines via the TLR2 and TLR4 pathways. Mitogen activated protein kinase, phospatidylinositol-4,5-bisphosphate 3-kinases, and the NF-κB signaling pathways are involved in Rv3463-mediated macrophage activation. Furthermore, Rv3463 induced bactericidal effects in Mtb-infected macrophages through phagosome maturation and phagolysosomal fusion enhanced by phospatidylinositol-4,5-bisphosphate 3-kinases and Ca2+ signaling pathways and exhibited therapeutic effects in a short-term Mtb-infection mouse model. Overexpression of Rv3463 in M. smegmatis caused rapid clearance of bacteria in macrophages and mice. Our study suggests that Rv3463 is a promising target for the development of post-exposure tuberculosis vaccines or adjunct immune-therapy.


Subject(s)
Antigens, Bacterial/immunology , Bacterial Proteins/immunology , Macrophages/immunology , Mycobacterium tuberculosis/immunology , Tuberculosis Vaccines/therapeutic use , Tuberculosis/prevention & control , Animals , Antigens, Bacterial/metabolism , Bacterial Proteins/metabolism , Disease Models, Animal , Female , Humans , Lysosomes/immunology , Lysosomes/microbiology , Macrophage Activation , Macrophages/microbiology , Mice , Phagocytosis/immunology , Post-Exposure Prophylaxis/methods , Signal Transduction/immunology , THP-1 Cells , Toll-Like Receptor 2/metabolism , Toll-Like Receptor 4/metabolism , Tuberculosis/immunology , Tuberculosis/microbiology , Tuberculosis Vaccines/immunology , Vaccines, Subunit/immunology , Vaccines, Subunit/therapeutic use
17.
Microbes Infect ; 21(1): 40-49, 2019.
Article in English | MEDLINE | ID: mdl-29981934

ABSTRACT

Mycobacterial acyl carrier protein (AcpM; Rv2244) is a meromycolate extension acyl carrier protein of Mycobacterium tuberculosis (Mtb), which participates in multistep mycolic acid biosynthesis. However, the function of AcpM in host-mycobacterium interactions during infection remains largely uncharacterized. Here we show that AcpM inhibits host cell apoptosis during mycobacterial infection. To examine the function of AcpM during infection, we generated a recombinant Mycobacterium smegmatis (M. smegmatis) strain overexpressing AcpM (Ms_AcpM) and a strain transformed with an empty vector (Ms_Vec). Ms_AcpM promoted intracellular survival of M. smegmatis and led to a significant decrease in the death rate of primary bone marrow-derived macrophages (BMDMs). Importantly, Ms_AcpM showed significantly decreased reactive oxygen species (ROS) generation and activation of c-Jun N-terminal kinase (JNK) signaling compared with Ms_Vec. In addition, treatment of BMDMs with recombinant AcpM significantly inhibited the apoptosis and ROS/JNK signaling induced by M. smegmatis. Moreover, recombinant AcpM enhanced intracellular survival of Mtb H37Rv. Taken together, these results indicate that AcpM plays a role as a virulence factor by modulating host cell apoptosis during mycobacterial infection.


Subject(s)
Apoptosis/genetics , Bacterial Proteins/metabolism , Carrier Proteins/metabolism , JNK Mitogen-Activated Protein Kinases/metabolism , Macrophages/pathology , Mycobacterium tuberculosis/chemistry , Reactive Oxygen Species/metabolism , Animals , Apoptosis/drug effects , Bacterial Proteins/genetics , Bacterial Proteins/pharmacology , Carrier Proteins/genetics , Carrier Proteins/pharmacology , Cells, Cultured , Female , Gene Expression , JNK Mitogen-Activated Protein Kinases/genetics , Macrophages/metabolism , Macrophages/microbiology , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Microbial Viability/drug effects , Mycobacterium Infections/immunology , Mycobacterium Infections/metabolism , Mycobacterium Infections/microbiology , Mycobacterium smegmatis/genetics , Mycobacterium smegmatis/physiology , Mycobacterium tuberculosis/genetics , Mycobacterium tuberculosis/physiology , RAW 264.7 Cells , Signal Transduction/drug effects
18.
Nat Commun ; 9(1): 3048, 2018 08 06.
Article in English | MEDLINE | ID: mdl-30082838

ABSTRACT

The use of CRISPR-Cas9 as a therapeutic reagent is hampered by its off-target effects. Although rationally designed S. pyogenes Cas9 (SpCas9) variants that display higher specificities than the wild-type SpCas9 protein are available, these attenuated Cas9 variants are often poorly efficient in human cells. Here, we develop a directed evolution approach in E. coli to obtain Sniper-Cas9, which shows high specificities without killing on-target activities in human cells. Unlike other engineered Cas9 variants, Sniper-Cas9 shows WT-level on-target activities with extended or truncated sgRNAs with further reduced off-target activities and works well in a preassembled ribonucleoprotein (RNP) format to allow DNA-free genome editing.


Subject(s)
CRISPR-Cas Systems , Directed Molecular Evolution , DNA/genetics , Escherichia coli/genetics , Gene Editing , HEK293 Cells , Humans , Plasmids/metabolism , RNA, Guide, Kinetoplastida/genetics , Recombinant Proteins/chemistry , Ribonucleoproteins/chemistry , Substrate Specificity
19.
Oncotarget ; 8(44): 77041-77049, 2017 Sep 29.
Article in English | MEDLINE | ID: mdl-29100368

ABSTRACT

The ground-breaking discovery of the reprogramming of somatic cells into pluripotent cells, termed induced pluripotent stem cells (iPSCs), was accomplished by delivering 4 transcription factors, Oct4, Sox2, Klf4, and c-Myc, into fibroblasts. Since then, several efforts have attempted to unveil other factors that are directly implicated in or might enhance reprogramming. Importantly, a number of transcription factors are reported to retain reprogramming activity. A previous study suggested Gli-similar 1 (Glis1) as a factor that enhances the reprogramming of fibroblasts during iPSC generation. However, the implication of other Glis members, including Glis2 and Glis3 (variants 1 and 2), in cellular reprogramming remains unknown. In this study, we investigated the potential involvement of human Glis family proteins, including hGlis1-3, in cellular reprogramming. Our results demonstrate that hGlis1, which is reported to reprogram human fibroblasts, promotes the reprogramming of human adipose-derived stromal cells (hADSCs), indicating that the reprogramming activity of Glis1 is not cell type-specific. Strikingly, hGlis3 promoted the reprogramming of hADSCs as efficiently as hGlis1. On the contrary, hGlis2 showed a strong negative effect on reprogramming. Together, our results reveal clear differences in the cellular reprogramming activity among Glis family members and provide valuable insight into the development of a new reprogramming strategy using Glis family proteins.

20.
Cell Death Dis ; 8(8): e3012, 2017 08 24.
Article in English | MEDLINE | ID: mdl-28837151

ABSTRACT

Mycobacterium abscessus (MAB) is a species of nontuberculous mycobacteria (NTM) and a major causative pathogen of pulmonary diseases especially in patients with cystic fibrosis. MAB infection is notoriously difficult to treat because of its intrinsic or inducible resistance to most antibiotics. The rough (R) morphotype of MAB, lacking cell surface glycopeptidolipids (GPLs), is associated with more severe and persistent infection than the smooth (S) type; however, the mechanisms underlying the R type's virulence and the relation with GPLs remain unclear. In this study, we found that R-type MAB is much more proapoptotic than the S type, as a result of GPL-mediated inhibition of macrophage apoptosis. Polar GPLs inhibited an apoptotic response (induced by proapoptotic stimuli) by suppressing ROS production and the cytochrome c release and by preserving mitochondrial transmembrane potential. Furthermore, GPLs were found to be targeted to mitochondria and interacted with cyclophilin D; their acetylation was essential for this interaction. Finally, GPLs inhibited the intracellular growth and bacterial spreading of R-type MAB among macrophages via apoptosis inhibition. These findings suggest that GPLs limit MAB virulence by inhibiting apoptosis and the spread of bacteria and therefore provide a novel insight into the mechanism underlying virulence of MAB.


Subject(s)
Cyclophilins/metabolism , Macrophages/metabolism , Mitochondria/metabolism , Mycobacterium abscessus/pathogenicity , Nontuberculous Mycobacteria/pathogenicity , Apoptosis , Peptidyl-Prolyl Isomerase F , Humans
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