The impact of PARPs and ADP-ribosylation on inflammation and host-pathogen interactions.

Poly-adenosine diphosphate-ribose polymerases (PARPs) promote ADP-ribosylation, a highly conserved, fundamental posttranslational modification (PTM). PARP catalytic domains transfer the ADP-ribose moiety from NAD+ to amino acid residues of target proteins, leading to mono- or poly-ADP-ribosylation (MARylation or PARylation). This PTM regulates various key biological and pathological processes. In this review, we focus on the roles of the PARP family members in inflammation and host-pathogen interactions. Here we give an overview the current understanding of the mechanisms by which PARPs promote or suppress proinflammatory activation of macrophages, and various roles PARPs play in virus infections. We also demonstrate how innovative technologies, such as proteomics and systems biology, help to advance this research field and describe unanswered questions.

Cellular Heterogeneity of Activated Primary Human Macrophages and Associated Drug-Gene Networks: From Biology to Precision Therapeutics.

BACKGROUND: Interferon-γ (IFNγ) signaling plays a complex role in atherogenesis. IFNγ stimulation of macrophages permits in vitro exploration of proinflammatory mechanisms and the development of novel immune therapies. We hypothesized that the study of macrophage subpopulations could lead to anti-inflammatory interventions. METHODS: Primary human macrophages activated by IFNγ (M(IFNγ)) underwent analyses by single-cell RNA sequencing, time-course cell-cluster proteomics, metabolite consumption, immunoassays, and functional tests (phagocytic, efferocytotic, and chemotactic). RNA-sequencing data were analyzed in LINCS (Library of Integrated Network-Based Cellular Signatures) to identify compounds targeting M(IFNγ) subpopulations. The effect of compound BI-2536 was tested in human macrophages in vitro and in a murine model of atherosclerosis. RESULTS: Single-cell RNA sequencing identified 2 major clusters in M(IFNγ): inflammatory (M(IFNγ)i) and phagocytic (M(IFNγ)p). M(IFNγ)i had elevated expression of inflammatory chemokines and higher amino acid consumption compared with M(IFNγ)p. M(IFNγ)p were more phagocytotic and chemotactic with higher Krebs cycle activity and less glycolysis than M(IFNγ)i. Human carotid atherosclerotic plaques contained 2 such macrophage clusters. Bioinformatic LINCS analysis using our RNA-sequencing data identified BI-2536 as a potential compound to decrease the M(IFNγ)i subpopulation. BI-2536 in vitro decreased inflammatory chemokine expression and secretion in M(IFNγ) by shrinking the M(IFNγ)i subpopulation while expanding the M(IFNγ)p subpopulation. BI-2536 in vivo shifted the phenotype of macrophages, modulated inflammation, and decreased atherosclerosis and calcification. CONCLUSIONS: We characterized 2 clusters of macrophages in atherosclerosis and combined our cellular data with a cell-signature drug library to identify a novel compound that targets a subset of macrophages in atherosclerosis. Our approach is a precision medicine strategy to identify new drugs that target atherosclerosis and other inflammatory diseases.

A Novel Spectral Annotation Strategy Streamlines Reporting of Mono-ADP-ribosylated Peptides Derived from Mouse Liver and Spleen in Response to IFN-γ.

Mass-spectrometry-enabled ADP-ribosylation workflows are developing rapidly, providing researchers a variety of ADP-ribosylome enrichment strategies and mass spectrometric acquisition options. Despite the growth spurt in upstream technologies, systematic ADP-ribosyl (ADPr) peptide mass spectral annotation methods are lacking. HCD-dependent ADP-ribosylome studies are common, but the resulting MS2 spectra are complex, owing to a mixture of b/y-ions and the m/p-ion peaks representing one or more dissociation events of the ADPr moiety (m-ion) and peptide (p-ion). In particular, p-ions that dissociate further into one or more fragment ions can dominate HCD spectra but are not recognized by standard spectral annotation workflows. As a result, annotation strategies that are solely reliant upon the b/y-ions result in lower spectral scores that in turn reduce the number of reportable ADPr peptides. To improve the confidence of spectral assignments, we implemented an ADPr peptide annotation and scoring strategy. All MS2 spectra are scored for the ADPr m-ions, but once spectra are assigned as an ADPr peptide, they are further annotated and scored for the p-ions. We implemented this novel workflow to ADPr peptides enriched from the liver and spleen isolated from mice post 4 h exposure to systemic IFN-γ. HCD collision energy experiments were first performed on the Orbitrap Fusion Lumos and the Q Exactive, with notable ADPr peptide dissociation properties verified with CID (Lumos). The m-ion and p-ion series score distributions revealed that ADPr peptide dissociation properties vary markedly between instruments and within instrument collision energy settings, with consequences on ADPr peptide reporting and amino acid localization. Consequentially, we increased the number of reportable ADPr peptides by 25% (liver) and 17% (spleen) by validation and the inclusion of lower confidence ADPr peptide spectra. This systematic annotation strategy will streamline future reporting of ADPr peptides that have been sequenced using any HCD/CID-based method.

Systems Approach to Discovery of Therapeutic Targets for Vein Graft Disease: PPARα Pivotally Regulates Metabolism, Activation, and Heterogeneity of Macrophages and Lesion Development.

BACKGROUND: Vein graft failure remains a common clinical challenge. We applied a systems approach in mouse experiments to discover therapeutic targets for vein graft failure. METHODS: Global proteomics and high-dimensional clustering on multiple vein graft tissues were used to identify potential pathogenic mechanisms. The PPARs (peroxisome proliferator-activated receptors) pathway served as an example to substantiate our discovery platform. In vivo mouse experiments with macrophage-targeted PPARα small interfering RNA, or the novel, selective activator pemafibrate demonstrate the role of PPARα in the development and inflammation of vein graft lesions. In vitro experiments further included metabolomic profiling, quantitative polymerase chain reaction, flow cytometry, metabolic assays, and single-cell RNA sequencing on primary human and mouse macrophages. RESULTS: We identified changes in the vein graft proteome associated with immune responses, lipid metabolism regulated by the PPARs, fatty acid metabolism, matrix remodeling, and hematopoietic cell mobilization. PPARα agonism by pemafibrate retarded the development and inflammation of vein graft lesions in mice, whereas gene silencing worsened plaque formation. Pemafibrate also suppressed arteriovenous fistula lesion development. Metabolomics/lipidomics, functional metabolic assays, and single-cell analysis of cultured human macrophages revealed that PPARα modulates macrophage glycolysis, citrate metabolism, mitochondrial membrane sphingolipid metabolism, and heterogeneity. CONCLUSIONS: This study explored potential drivers of vein graft inflammation and identified PPARα as a novel potential pharmacological treatment for this unmet medical need.

Senescence-associated secretory phenotype promotes chronic ocular graft-vs-host disease in mice and humans.

Chronic graft-vs-host disease (cGVHD) is a multifactorial inflammatory disease that affects patients undergoing hematopoietic stem cell transplantation. Multiple organs, including the lacrimal glands (LGs), are negatively affected by cGVHD and lose function due to the resultant fibrosis. An abnormal immune response is thought to be a major factor in the development of chronic ocular GVHD, which is currently treated primarily with immunosuppressive therapies. However, all the treatments yield unsatisfactory outcomes, and additional treatment strategies are needed. To meet this unmet medical need, we aimed to elucidate an additional pathway of chronic ocular GVHD. Our findings suggest a potential association between chronic ocular GVHD pathogenesis and stress-induced cellular senescence through the senescence-associated secretory phenotype (SASP). Senescent cells produce cytokines and chemokines, such as IL-6 and CXCL9. Indeed, senescent cell accumulation was presumably associated with cGVHD development in LGs, as evidenced by the improvement in LGs after the selective elimination of senescent cells (senolysis) with ABT-263. Results in the sclerodermatous cGVHD mouse model suggest that inhibiting the major components of the SASP, including IL-6 and CXCL9, with senolytics is a potential novel strategy for treating cGVHD-affected LGs. Taken together, our results indicate a potential association between the SASP and cGVHD development in LGs and suggest that targeted senolytic treatment may be a new therapeutic option for this disease.

Inhibition of Vascular Adhesion Protein-1 for Treatment of Graft-Versus-Host Disease in Mice.

Graft-versus-host disease (GVHD) is a potentially lethal complication of hematopoietic stem cell transplantation (HSCT). GVHD comprises acute and chronic forms. To date, several approaches to treat acute GVHD or chronic GVHD have been reported. However, there is no literature precedent regarding all-in-one methods to address the 2 GVHD types. Severe inflammation in organs affected by GVHD is highly problematic, and vascular adhesion protein-1 (VAP-1) is known to be detrimentally involved in various inflammatory diseases. Based on the previous reports, we envisaged that there would be a link between GVHD and VAP-1, and we strived to create effective therapies for the 2 types of GVHD using a mouse model of GVHD. Our investigation indicated that expression of VAP-1 was elevated in organs disordered by GVHD. Hence, we subsequently attempted to block VAP-1 by using a novel inhibitor. Our results indicate that systemic injection of the inhibitor prevented aberrant influx of inflammatory cells into tissues and thereby mitigate GVHD-elicited inflammation and fibrosis. Collectively, our study suggests that the increased expression of VAP-1 is detrimentally associated with the development of GVHD and that the blockade of VAP-1 could be a promising medical modality to combat the acute and chronic variants.-Mukai, S., Ogawa, Y., Kawakami, Y., Mashima, Y., Tsubota, K. Inhibition of vascular adhesion protein-1 for treatment of graft-versus-host disease in mice.

Long-Term Topical Diquafosol Tetrasodium Treatment of Dry Eye Disease Caused by Chronic Graft-Versus-Host Disease: A Retrospective Study.

OBJECTIVES: The aim of this study was to assess the safety and efficacy of long-term use of 3% diquafosol ophthalmic solution (DQS), an eye drop for mucin production and water secretion, for treating dry eye disease (DED) caused by chronic graft-versus-host disease (cGVHD). METHODS: We retrospectively evaluated the safety and efficacy of DQS in 10 patients with mild to moderate cGVHD-induced DED. The efficacy was assessed by (1) degree of symptoms, (2) Schirmer I test value, (3) tear film breakup time (TFBUT), and (4) fluorescein and rose bengal scores. RESULTS: The median duration of DQS treatment was 12.0 months (range 6-17 months). DQS was effective for relieving severe pain caused by cGVHD-related DED. Although the Schirmer I test value was enhanced only marginally, the long-term application of DQS significantly improved the corneal/conjunctival epitheliopathy and tear film stability: the fluorescein score improved from 5.9±0.6 to 1.3±1.1 points (P=1.771×10); rose bengal staining from 4.7±1.6 to 2.0±1.5 points (P=0.008); and TFBUT from 2.6±0.9 to 4.6±1.6 mm (P=0.009). Furthermore, the long-term DQS treatment caused no major adverse events. CONCLUSIONS: This study suggested that long-term DQS treatment is a safe and robust approach for alleviating cGVHD-related DED.

Long-term rebamipide and diquafosol in two cases of immune-mediated dry eye.

PURPOSE: Two new drugs with mucin-inducing and secretion-promotive effects, rebamipide and diquafosol, were recently approved as topical dry-eye treatments. We report two cases in which the long-term use of mucin-inducing eye drops improved chronic ocular graft-versus-host disease (cGVHD)-related dry eye and ocular cicatricial pemphigoid (OCP)-like disease. CASE REPORTS: Case 1. A 61-year-old woman had cGVHD-related dry eye that resisted traditional medications. Next, we use topical diquafosol in addition to conventional treatments. The patient used diquafosol for 6 months without experiencing any side effects. The symptoms, including dry-eye sensation, ocular pain, foreign body sensation, and photophobia, as well as ocular surface findings including fluorescein and rose bengal scores and tear break-up time (TBUT), partly improved. To further improve the clinical signs and symptoms and decrease chronic inflammation, rebamipide was added to diquafosol. The symptoms, TBUT, and fluorescein and rose bengal scores markedly improved after long-term dual treatment without any side effects for 6 months. Case 2. A 77-year-old woman had OCP-like disease with dry eye. The patient did not improve using the currently available conventional treatments. Next, we use topical rebamipide in addition to conventional treatments. Symptoms including asthenopia, dry-eye sensation, ocular pain, and dull sensation, as well as fluorescein and rose bengal scores and TBUT, partly improved. Specifically, functional visual acuity was markedly improved after commencement of rebamipide. To further improve the clinical signs and symptoms and increase tear film stability and tear film volume, diquafosol was added to rebamipide. The combination of diquafosol and rebamipide worked for the patient. Improvements were seen in several symptoms, fluorescein and rose bengal scores, Schirmer test value, and TBUT without any side effects for 12 months. CONCLUSIONS: Long-term treatment with topical rebamipide and diquafosol can improve dry eye in patients with cGVHD or OCP-like disease.

Selective Btk inhibition by PRN1008/PRN473 blocks human CLEC-2 & PRN473 reduces venous thrombosis formation in mice.

Platelet CLEC-2 is a hemITAM-containing receptor which has a critical role in venous thrombosis, but minimal involvement in haemostasis. CLEC-2 can be blocked by Btk inhibitors. Treatment with ibrutinib is associated with increased bleeding due to off-target inhibition of Src family kinases (SFKs). Patients with X-linked agammaglobulinemia (XLA) who lack Btk however do not bleed, suggesting selective Btk inhibition is a viable antithrombotic strategy. We assessed the effects of selective Btk inhibitors PRN1008 (rilzabrutinib) and PRN473 on platelet signalling and function mediated by CLEC-2 and GPVI. We used healthy donor and XLA platelets to determine off-target inhibitor effects. Inferior vena cava (IVC) stenosis and Salmonella infection mouse models were used to assess antithrombotic effects of PRN473 in vivo. PRN1008 and PRN473 potently inhibited CLEC-2-mediated platelet activation to rhodocytin. No off-target inhibition of SFKs was seen. PRN1008 treatment of Btk-deficient platelets resulted in minor additional inhibition of aggregation and tyrosine phosphorylation, likely reflecting inhibition of Tec. No effect on GPCR-mediated platelet function was observed. PRN473 significantly reduced the number of thrombi in podoplanin positive vessels following Salmonella infection and the presence of IVC thrombosis following vein stenosis. The potent inhibition of human platelet CLEC-2, and reduced thrombosis in in vivo models, together with the lack of off-target SFK inhibition and absence of bleeding reported in rilzabrutinib treated immune thrombocytopenia patients, suggest Btk inhibition as a promising antithrombotic strategy.

Immobilization of magnesium ammonium phosphate crystals within microchannels for efficient ammonia removal.

Magnesium ammonium phosphate was formed in flow-through microchannels of silica monoliths using two different methods to fabricate materials that show efficient ammonia adsorption performance from wastewater with low hydraulic resistance. Magnesium ammonium phosphate crystals in these materials release ammonia when heated at 378 K, yielding primarily magnesium hydrogen phosphate. When this material was used for ammonia removal from an aqueous solution containing 100 ppm ammonia in a flow system, the material readily removed ammonia, decreasing the ammonia concentration to 25 ppm. The material can be reactivated by the same procedure and used again for ammonia removal. Hydrodynamic resistance through the lengths of the materials depend on the shape of the immobilized crystals, showing that needle-like crystals are more effective to cause less resistance than plate-like particles. The material containing needle-like crystals causes only approximately one-eighth of the hydraulic resistance that a packed column consisted of spherical particles with a typical bed porosity of 0.5 does. Thus, these results demonstrate the high applicability of the material for ammonia removal from wastewater in a continuous process.

Improving porous properties of activated carbon from carbon gel by the OTA method.

High-surface-area microporous-mesoporous carbons were produced from carbon gel by applying the three consecutive steps of air oxidation, thermal treatment, and activation (the OTA method) to the gel. The formation of mesopores occurs both inside and outside the nanoparticles which form the carbon gel, while micropores are predominantly created within the nanoparticles. The OTA method offered a greater increase in pore volume and BET surface area of the resulting activated carbon in comparison with conventional CO2 activation either under the same activation conditions or at the same degree of carbon burn-off. Under the best preparation conditions, the maximum values of micropore volume, mesopore volume, and BET surface area achievable using the OTA method were found to be 1.19 cm3 g-1, 1.81 cm3 g-1, and 2920 m2 g-1, respectively at a 72% carbon burn-off. The larger increase in porous properties of activated carbon gel prepared by the OTA method over those based on conventional activation stems from the effects of the oxidation and heat treatment steps of the OTA method that could produce a large number of reaction sites which lead to efficient pore formation during the following CO2 activation process.

Stable triazolylphosphonate analogues of phosphohistidine.

Histidine-phosphorylated proteins and the corresponding kinases are important components of bacterial and eukaryotic cell-signalling pathways, and are therefore potential drug targets. The study of these biomolecules has been hampered by the lability of the phosphoramidate functional group in the phosphohistidines and the lack of generic antibodies. Herein, the design and concise synthesis of stable triazolylphosphonate analogues of N1- and N3-phosphohistidine, and derivatives suitable for bioconjugation, are described.

Eyelid blood vessel and meibomian gland changes in a sclerodermatous chronic GVHD mouse model.

PURPOSE: To investigate pathological changes in blood vessels and meibomian glands (MGs) in the eyelids of sclerodermatous chronic graft-versus-host disease (cGVHD) model mice. METHODS: We used an established major histocompatibility complex compatible, multiple minor histocompatibility antigen-mismatched sclerodermatous cGVHD mouse model. Blood vessels and MGs of eyelids from allogeneic bone marrow transplantation (allo-BMT) recipient mice and syngeneic bone marrow transplantation (syn-BMT) recipient mice were assessed by histopathology, immunohistochemistry and transmission electron microscopy. Peripheral blood samples from the recipients were examined by flow cytometry. RESULTS: Allo-BMT samples showed dilating, tortuous and branching vessels and shrunk MGs in the eyelids; showed significantly higher expression of VEGFR2 (p = 0.029), CD133 (p = 0.016), GFP (p = 0.006), and α-SMA (p = 0.029) in the peripheral MG area; showed endothelial damage and activation, fibrotic change, and immune cell infiltration into MGs compared with syn-BMT samples. Fewer Ki-67+ cells were observed in allo- and syn-BMT samples than in wild-type samples (p = 0.030). Ultrastructural changes including endothelial injury and activation, fibroblast activation, granulocyte degranulation, immune cell infiltration into MGs, and necrosis, apoptosis of MG basal cells were found in allo-BMT samples compared with syn-BMT samples. CONCLUSION: A series of our studies indicated that cGVHD can cause eyelid vessel and MGs changes, including endothelial injury and activation, neovascularization, early fibrotic changes, immune cell infiltration, MG basal cell necrosis and apoptosis, and resultant MG atrophy.

Development of an efficient CVD technique to prepare TiO2/porous-carbon nanocomposites for high rate lithium-ion capacitors.

Titanium dioxide is a promising electrode material for lithium-ion capacitors. When using TiO2 as an electrode material, it is necessary to combine it with carbon at the nanometer level to improve its low electrical conductivity and low reactivity with Li+. However, preparation methods of reported TiO2/porous-carbon nanocomposites are generally not cost-effective, and their productivities are low. In this study, the vacuum liquid-pulse chemical vapor deposition (VLP-CVD) technique was developed to easily prepare TiO2/porous-carbon nanocomposites, where TiO2 nanoparticles with a diameter of ∼4 nm could be homogeneously deposited inside the pores of meso- or macroporous carbons. Because the deposited TiO2 nanoparticles had access to effective electrically conductive paths formed by the porous-carbon substrate, they showed a high discharge capacity of ∼200 mA h g-1-TiO2 (based on TiO2 weight). In particular, the composite prepared from macroporous carbon showed an extremely high rate performance, where 50% of the discharge capacity was retained at a current density of 15 000 mA g-1 when compared to that measured at 50 mA g-1. In addition, the composite also showed very high cyclability, where 80% of the discharge capacity was retained at the 10 000th cycle. Because the VLP-CVD technique can be performed using simple apparatus and commercially available starting materials, it can be expected to boost industrial production of TiO2/porous-carbon for lithium-ion capacitors.

Post-annealed graphite carbon nitride nanoplates obtained by sugar-assisted exfoliation with improved visible-light photocatalytic performance.

Two-dimensional (2D) graphitic carbon nitride (g-C3N4) nanoplates (CNNP) have become a hot research topic in photocatalysis due to their small thickness and large specific surface area that favors charge transport and catalytic surface reactions. However, the wide application of 2D g-C3N4 nanoplates prepared by ordinary methods suffers from increased band gaps with a poor solar harvesting capability caused by the strong quantum confinement effect and reduced conjugation distance. In this paper, a facile approach of exfoliation and the following fast thermal treatment of the bulk g-C3N4 is proposed to obtain a porous few-layered g-C3N4 with nitrogen defects. Due to the preferable crystal, textural, optical and electronic structures, the as-obtained porous CNNP demonstrated a significantly improved photocatalytic activity towards water splitting than the bulk g-C3N4 and even the 3 nm-thick CNNP obtained by sugar-assisted exfoliation of the bulk g-C3N4. The difference in the enhancement factors between the H2O splitting and organic decomposition has revealed the effect of N defects. This study offers insightful outlooks on the scalable fabrication of a porous few-layered structure with a promoted photocatalytic performance.

Cluster of differentiation 30 expression in lacrimal gland and conjunctival tissues in patients with Sjögren's syndrome: Case series.

INTRODUCTION: Sjögren's syndrome (SS) often causes lymphoproliferative disorders such as malignant lymphoma and macroglobrinemia. Approximately 5% of long-term follow-up SS patients develop malignant lymphoma. Recently, the tumor necrosis factor receptor superfamily cluster of differentiation 30 (CD30) has been thought to be implicated in malignant cells in organs affected by Hodgikin lymphoma or in a prognostic marker of diffuse large B cell lymphoma. In this study, we investigated CD30 expression in lacrimal gland and conjunctiva in patients with SS. METHODS: We examined lacrimal gland and conjunctival tissues for the diagnosis from 3 female SS patients with a median age of 51 and 3 female chronic graft-versus-host disease (cGVHD) patients with a median age of 41. Histological analysis of these tissues of the remaining samples was conducted by methods including immunohistochemistry and electron microscopy (#20090277). We analyzed the expression and localization of cluster of differentiation 4 (CD4), cluster of differentiation 8 (CD8), cluster of differentiation 20 (CD20), CD30, and Interferon-γ in tissue sections prepared from lacrimal glands and conjunctiva in 3 each of SS and cGVHD patients. RESULTS: There were more B cells and plasma cells in lobules of SS-affected lacrimal glands than in those of their cGVHD-affected counterparts. Interferon-γ was expressed on endothelia of capillaries in SS-affected lacrimal gland and conjunctival tissues whereas it was expressed on fibroblasts in their GVHD-affected equivalents. Furthermore, lacrimal glands and conjunctiva disordered by SS had a greater number of CD30 cells than those disordered by cGVHD. CONCLUSION: Our results suggest that CD30 cells are increased in lacrimal glands and conjunctiva affected by SS and that a subset of SS patients are thereby at risk of development malignant lymphoma.

Commensal microflora in human conjunctiva; characteristics of microflora in the patients with chronic ocular graft-versus-host disease.

PURPOSE: To investigate the transformation in the composition of ocular surface microflora. Evidence shows that microbial diversity correlates with autoimmune disorders. Chronic ocular graft-versus-host disease (GVHD) is the lethal complication after hematopoietic stem cell transplantation (HSCT) which influences patients' quality of life. It has a similar pathophysiology to autoimmune disorders but the relation of the microbial status especially in the ocular surface and chronic ocular GVHD is still unknown. METHODS: We prospectively harvested conjunctival microorganism with a cotton swab from following 3 groups, 32 eyes/20 ocular GVHD patients (9 males, 11 females), 28 eyes/20 nonGVHD cases (10 males, 10 females) which defined as post hematopoietic stem cell transplantation and without ocular GVHD, and 20 eyes/11 controls (7 males, 4 females). Conventional culture-based methods were performed to examine the microbial community. RESULTS: Ocular surface microbes in the GVHD patients was more complex in diversity compared with in the nonGVHD patients and the control. Staphylococcus species, Alpha-haemo Streptococcus, Corynebacterium species, Propionibacterium Acnes, Aerobic gram-positive cocci, Haemophilus Influenzae, and Aerobic gram-positive rod were observed in the GVHD patients, whereas only a few species detected in the other groups. CONCLUSIONS: We found that ocular surface microbes in the GVHD patients is more diverse than that in the nonGVHD patients and the controls. These results suggest the alternation of microbes are involved in the pathogenic process of the chronic ocular GVHD. Further examination using state-of-the-art methods will be needed to gain greater insights into the diversity of microflora on the chronic GVHD-affected ocular surface.

Synthesis of Mg-Al Mixed Oxides with Markedly High Surface Areas from Layered Double Hydroxides with Organic Sulfonates.

Mg-Al mixed oxides with record-high surface areas and basic site concentrations were synthesized from Mg-Al layered double hydroxides with interlayer isethionate (Ise) or 3-hydroxy-1-propanesulfonate (HPS). Anion exchange of interlayer CO3 2- in synthetic hydrotalcites with the organic sulfonates induces disorders in layer stacking as characterized by powder X-ray diffraction and enables facile delamination in water. Thermal treatment of materials anion-exchanged by Ise (MgAl-Ise) and HPS (MgAl-HPS) in N2 and H2 resulted in the formation of Mg-Al mixed oxides with marked enhancement in Brunauer-Emmett-Teller (BET) surface area relative to those treated in air. Treatment in a flow of H2 is particularly effective, doubling the surface area of mixed oxides derived from MgAl-Ise relative to those obtained in a flow of N2. A higher degree of disorder in layer stacking in MgAl-HPS than MgAl-Ise resulted in the formation of Mg-Al mixed oxides with higher surface areas than those from MgAl-Ise. As a result, thermal activation of MgAl-HPS in a flow of H2 yielded Mg-Al mixed oxides with the highest BET surface area (410 m2 g-1) and CO2 uptake (1.6 mmol g-1 at 25 °C and 100 kPa) in all samples. These values are significantly higher than those obtained from the initial hydrotalcites as well as those reported in the literature with similar Mg-Al ratios. Investigation of the thermal activation steps by thermogravimetric analysis and mass spectrometry indicates that the key factors to achieve high surface area and CO2 uptake are to weaken interactions between layers by inducing stacking disorders and to facilitate the removal of interlayer sulfonates by preventing the formation of sulfates from them via thermal activation under a reducing environment.

Therapeutic potential of tranilast for the treatment of chronic graft-versus-host disease in mice.

Chronic graft-versus-host disease (cGVHD) is a marked complication of hematopoietic stem cell transplantation, and multiple organs can be affected by cGVHD-induced inflammation and fibrosis. In clinical settings, immunosuppressive agents have been the last resort to treat cGVHD. However, it has been only partially effective for cGVHD. Hence, efficacious treatment of cGVHD is eagerly awaited. Our previous work suggested that oxidative stress was elevated in cGVHD-disordered lacrimal glands and that epithelial-to-mesenchymal transition (EMT) was implicated in fibrosis caused by ocular cGVHD. In addition, our recent article demonstrated that thioredoxin interaction protein (TXNIP) and transcription factor nuclear factor kappa-light-chain-enhancer of activated B cells (NF-𝛋B) were associated with the development of cGVHD. After our search for effective drugs, we chose tranilast to combat systemic cGVHD. Tranilast is known to (1) act as an inhibitor of the inflammatory molecules TXNIP and NF-κB and (2) exert anti-fibrotic, anti-EMT and anti-oxidative effects. To investigate the effectiveness of tranilast for cGVHD, we used an MHC-compatible, multiple minor histocompatibility antigen-mismatched murine model of cGVHD. Tranilast or a solvent-vehicle were orally given to the allogeneic bone marrow transplantation (allo-BMT) recipients from the day before allo-BMT (Day-1) to Day 27 after allo-BMT. Their cGVHD-vulnerable organs were collected Day 28 after allo-BMT and analyzed by using various methods such as histology, immunohistochemistry and immunoblotting. As indicated by our results, tranilast alleviated cGVHD-elicited inflammation and fibrosis by suppressing the expression and/or activation of TXNIP and NF-κB and preventing EMT. Taken together, although this strategy may not be a complete cure for cGVHD, tranilast could be a promising medication to ameliorate cGVHD-triggered disabling symptoms.

Novel elucidation and treatment of pancreatic chronic graft-versus-host disease in mice.

Chronic graft-versus-host disease (cGVHD) is a severe complication of allogeneic haematopoietic stem cell transplantation. There is a growing understanding of cGVHD, and several effective therapies for cGVHD have been reported. However, pancreatic cGVHD is a potentially untapped study field. Our thought-provoking study using a mouse model of cGVHD suggested that the pancreas could be impaired by cGVHD-induced inflammation and fibrosis and that endoplasmic reticulum (ER) stress was augmented in the pancreas affected by cGVHD. These findings urged us to treat pancreatic cGVHD through reduction of ER stress, and we used 4-phenylbutyric acid (PBA) as an ER stress reducer. A series of experiments has indicated that PBA can suppress cGVHD-elicited ER stress in the pancreas and accordingly alleviate pancreatic cGVHD. Furthermore, we focused on a correlation between epithelial to mesenchymal transition (EMT) and fibrosis in the cGVHD-affected pancreas, because EMT was conceivably implicated in various fibrosis-associated diseases. Our investigation has suggested that the expression of EMT markers was increased in the cGVHD-disordered pancreas and that it could be reduced by PBA. Taken together, we have provided a clue to elucidate the pathogenic process of pancreatic cGVHD and created a potentially effective treatment of this disease using the ER stress alleviator PBA.