Intensive Surveillance of Porcine-Rhesus Kidney Xenotransplant Using Different Ultrasound Techniques.

BACKGROUND: Significant progress has been made in kidney xenotransplantation in the past few years, and this field is accelerating towards clinical translation. Therefore, surveillance of the xenograft with appropriate tools is of great importance. Ultrasonography has been widely used in kidney allotransplantation and served as an economical and non-invasive method to monitor the allograft. However, questions remain whether the ultrasonographic criteria established for human kidney allograft could also be applied in xenotransplantation. METHODS: In the current study, we established a porcine-rhesus life sustaining kidney xenotransplantation model. The xenograft underwent intensive surveillance using gray-scale, colorful Doppler ultrasound as well as 2D shear wave elastography. The kidney growth, blood perfusion, and cortical stiffness were measured twice a day. These parameters were compared with the clinical data including urine output, chemistry, and pathological findings. RESULTS: The observation continued for 16 days after transplantation. Decline of urine output and elevated serum creatinine were observed on POD9 and biopsy proven antibody-mediated rejection was seen on the same day. The xenograft underwent substantial growth, with the long axis length increased by 32% and the volume increased by threefold at the end of observation. The resistive index of the xenograft arteries elevated in response to rejection, together with impaired cortical perfusion, while the peak systolic velocity (PSV) was not compromised. The cortical stiffness also increased along with rejection. CONCLUSION: In summary, the ultrasound findings of kidney xenograft shared similarities with those in allograft but possessed some unique features. A modified criteria needs to be established for further application of ultrasound in kidney xenotransplantation.

One-Pot Synthesis of Ce-SSZ-39 Zeolite with Performance in the NH3-SCR Reaction.

Cu-SSZ-39 zeolite with 8-membered rings is regarded as a very promising catalyst in the NH3-SCR reaction, but its hydrothermal stability still remains to be improved. One of the solutions to promote hydrothermal stability is the insertion of rare earth elements in the product. Nevertheless, normal ion exchange of rare earth elements limits their contents in the zeolite product due to their large hydrated ionic radius and alkaline environment under hydrothermal conditions. Herein, we for the first time present a new method for the one-pot synthesis of Ce-SSZ-39 zeolite under solvent-free conditions. The key to success is the use of Ce-FAU zeolite as a precursor. The obtained product shows good crystallinity, sheet-like morphology, large BET surface area, and 4-coordinated Al species. Detailed investigations illustrate that Ce species in the Cu/Ce-SSZ-39 zeolite micropore can prevent the dealumination and thus formation of CuAlOx species during hydrothermal aging at 850 °C for 16 h, giving the excellent hydrothermal stability and thus showing the excellent catalytic performance in the NH3-SCR reaction. One-pot synthesis of Ce-SSZ-39 zeolite with excellent catalytic performance might open a new door for developing very efficient selective catalytic reduction (SCR) catalysts in near future.

Design of an Organic Template for Synthesizing ITR Zeolites under Ge-Free Conditions.

Germanosilicate zeolites with various structures have been extensively synthesized, but the syntheses of corresponding zeolite structures in the absence of germanium species remain a challenge. One such example is an ITR zeolite structure, which is a twin of the ITH zeolite structure. Through the modification of a classic organic template for synthesizing ITH zeolites and thus designing a new organic template with high compatibility to ITR zeolite assisted by theoretical simulation, we, for the first time, show the Ge-free synthesis of an ITR structure including pure silica, aluminosilicate, and borosilicate ITR zeolites. These materials have high crystallinity, corresponding to an ITR content of more than 95%. In the methanol-to-propylene (MTP) reaction, the obtained aluminosilicate ITR zeolite exhibits excellent propylene selectivity and a long lifetime compared with conventional aluminosilicate ZSM-5 zeolite. The strategy for the design of organic templates might offer a new opportunity for rational syntheses of novel zeolites and, thus, the development of highly efficient zeolite catalysts in the future.

NPAS2 promotes aerobic glycolysis and tumor growth in prostate cancer through HIF-1A signaling.

BACKGROUND: Prostate cancer (PCa), one of the common malignant tumors, is the second leading cause of cancer-related deaths in men. The circadian rhythm plays a critical role in disease. Circadian disturbances are often found in patients with tumors and enable to promote tumor development and accelerate its progression. Accumulating evidence suggests that the core clock gene NPAS2 (neuronal PAS domain-containing protein 2) has been implicated in tumors initiation and progression. However, there are few studies on the association between NPAS2 and prostate cancer. The purpose of this paper is to investigate the impact of NPAS2 on cell growth and glucose metabolism in prostate cancer. METHODS: Quantitative real-time PCR (qRT-PCR), immunohistochemical (IHC) staining, western blot, GEO (Gene Expression Omnibus) and CCLE (Cancer Cell Line Encyclopedia) databases were used to analyze the expression of NPAS2 in human PCa tissues and various PCa cell lines. Cell proliferation was assessed using MTS, clonogenic assays, apoptotic analyses, and subcutaneous tumor formation experiments in nude mice. Glucose uptake, lactate production, cellular oxygen consumption rate and medium pH were measured to examine the effect of NPAS2 on glucose metabolism. The relation of NPAS2 and glycolytic genes was analyzed based on TCGA (The Cancer Genome Atlas) database. RESULTS: Our data showed that NPAS2 expression in prostate cancer patient tissue was elevated compared with that in normal prostate tissue. NPAS2 knockdown inhibited cell proliferation and promoted cell apoptosis in vitro and suppressed tumor growth in a nude mouse model in vivo. NPAS2 knockdown led to glucose uptake and lactate production diminished, oxygen consumption rate and pH elevated. NPAS2 increased HIF-1A (hypoxia-inducible factor-1A) expression, leading to enhanced glycolytic metabolism. There was a positive correlation with the expression of NPAS2 and glycolytic genes, these genes were upregulated with overexpression of NPAS2 while knockdown of NPAS2 led to a lower level. CONCLUSION: NPAS2 is upregulated in prostate cancer and promotes cell survival by promoting glycolysis and inhibiting oxidative phosphorylation in PCa cells.

Insights into SO2 Poisoning Mechanisms of Fresh and Hydrothermally Aged Cu-KFI Catalysts for NH3-SCR Reaction.

The complex poisoning of Cu-KFI catalysts by SO2 and hydrothermal aging (HTA) was investigated. The low-temperature activity of Cu-KFI catalysts was restrained by the formation of H2SO4 and then CuSO4 after sulfur poisoning. Hydrothermally aged Cu-KFI exhibited better SO2 resistance than fresh Cu-KFI since HTA significantly reduced the number of Brønsted acid sites, which were considered to be the H2SO4 storage sites. The high-temperature activity of SO2-poisoned Cu-KFI was basically unchanged compared to the fresh catalyst. However, SO2 poisoning promoted the high-temperature activity of hydrothermally aged Cu-KFI since it triggered CuOx into CuSO4 species, which was considered as an important role in the NH3-SCR reaction at high temperatures. In addition, hydrothermally aged Cu-KFI catalysts were more easily regenerated after SO2 poisoning than fresh Cu-KFI on account of the instability of CuSO4.

Extracellular vesicles from Lactobacillus druckerii inhibit hypertrophic scar fibrosis.

BACKGROUND: Hypertrophic scars (HS) affect millions of people each year and require better treatment strategies. Bacterial extracellular vesicles (EVs) are advantaged by low cost and high yield which was commonly used in the treatment of diseases. Here, we investigated the therapeutic efficacy of EVs obtained from Lactobacillus druckerii in hypertrophic scar. In vitro, the effects of Lactobacillus druckerii-derived EVs (LDEVs) on Collagen I/III and α-SMA in fibroblasts obtained from HS. In vivo, a scleroderma mouse model was used to investigate the effects of LDEVs on fibrosis. The impact of LDEVs on excisional wound healing was explored. The different proteins between PBS and LDEVs treated fibroblasts derived from hypertrophic scar were studied by untargeted proteomic analysis. RESULTS: In vitro, LDEVs treatment significantly inhibited the expression of Collagen I/III and α-SMA and cell proliferation of fibroblasts derived from HS. In vivo, LDEVs withdrawn the hypertrophic scar formation in scleroderma mouse model and decreased the expression of α-SMA. LDEVs promoted the proliferation of skin cells, new blood vessel formation and wound healing in excisional wound healing mice model. Moreover, proteomics has shown that LDEVs inhibit hypertrophic scar fibrosis through multiple pathways. CONCLUSIONS: Our results indicated that Lactobacillus druckerii-derived EVs has the potential application in the treatment of hypertrophic scars and any other fibrosis diseases.

Design of a Small Organic Template for the Synthesis of Self-Pillared Pentasil Zeolite Nanosheets.

Zeolite nanosheets with excellent mass transfer are attractive, but their successful syntheses are normally resulted from a huge number of experiments. Here, we show the design of a small organic template for the synthesis of self-pillared pentasil (SPP) zeolite nanosheets from theoretical calculations in interaction energies between organic templates and pentasil zeolite skeletons. As expected, the SPP zeolite nanosheets with the thickness at 10-20 nm have been synthesized successfully. Characterizations show that the SPP zeolite nanosheets with about 90% MFI and 10% MEL structures have good crystallinity, the house-of-card morphology, large surface area, and fully four-coordinated aluminum species. More importantly, methanol-to-propylene tests show that the SPP zeolite nanosheets exhibit much higher propylene selectivity and longer reaction lifetime than conventional ZSM-5 zeolite. These results offer a good opportunity to develop highly efficient zeolite catalysts in the future.

Systemic inflammation accelerates the adverse effects of air pollution on metabolic syndrome: Findings from the China health and Retirement Longitudinal Study (CHARLS).

Long-term exposure to air pollution and systemic inflammation are associated with increased prevalence of metabolic syndrome (MetS); however, their joint effects in Chinese middle-aged and older adults is unknown. In this cross-sectional study, 11,838 residents aged 45 years and older from the China Health and Retirement Longitudinal Study (CHARLS) Wave 3 in 2015 were included. MetS was diagnosed using the Joint Interim Societies' definition. C-Reactive Protein (CRP) was assessed to reflect systemic inflammation. Individual exposure to air pollutants (particulate matter with a diameter ≤2.5 µm (PM2.5) or ≤ 10 µm (PM10), sulfur dioxide (SO2), nitrogen dioxide (NO2), ozone (O3), and carbon monoxide (CO)) was evaluated using satellite-based spatiotemporal models according to participant residence at county-level. Generalized linear models (GLMs) were applied to examine the association between air pollution and MetS, and the modification effects of CRP between air pollution and MetS were estimated using interaction terms of CRP and air pollutants in the GLM models. The prevalence of MetS was 32.37%. The adjusted odd ratio (OR) of MetS was 1.192 (95% confidence interval (CI): 1.116, 1.272), 1.177 (95% CI: 1.103, 1.255), 1.158 (95% CI: 1.072, 1.252), 1.303 (95% CI: 1.211,1.403), 1.107 (95% CI: 1.046, 1.171) and 1.156 (95% CI:1.083, 1.234), per inter-quartile range increase in PM2.5 (24.04 µg/m3), PM10 (39.00 µg/m3), SO2 (19.05 µg/m3), NO2 (11.28 µg/m3), O3 (9.51 µg/m3) and CO (0.46 mg/m3), respectively. CRP was also associated with increased prevalence of MetS (OR = 1.049, 95% CI: 1.035, 1.064; per 1.90 mg/L increase in CRP). Interaction analysis suggested that high CRP levels enhanced the association between air pollution exposure and MetS. Long-term exposure to air pollution is associated with increased prevalence of MetS, which might be enhanced by systemic inflammation. Given the rapidly aging society and heavy burden of MetS, measures should be taken to improve air quality and reduce systemic inflammation.

Histone deacetylase 10 exerts antitumor effects on cervical cancer via a novel microRNA-223/TXNIP/Wnt/ß-catenin pathway.

Dysfunction of histone deacetylase 10 (HDAC10) has been suggested in the carcinogenesis of cervical cancer (CC). However, its association with microRNAs (miRNAs) in CC remains exclusive. Hence, this study aims to probe the role of HDAC10 in regulating CC cell proliferation, migration, and invasion and its correlation with the screened-out miRNA target. Microarray analysis and RT-qPCR revealed that HDAC10 expressed poorly in CC cells relative to human immortalized endocervical cells (End1/E6E7). Moreover, HDAC10 downregulation predicted poor survival for patients with CC. Overexpression of HDAC10 reduced CC cell biological activities in vitro and tumor growth and lung metastases in vivo. miR-223, upregulated in CC, was regulated by HDAC10 through histone acetylation, while miR-223 inhibited the effects of HDAC10 overexpression in CC. miR-223 targeted the 3'-UTR of thioredoxin interacting protein (TXNIP) and suppressed its expression, leading to increased CC development in vitro and in vivo. TXNIP overexpression impaired Wnt/ß-catenin pathway activity in CC cells.

Histone deacetylase 10 exerts anti-tumor effects on cervical cancer via a novel microRNA-223/TXNIP/Wnt/ß-catenin pathway.

Dysfunction of histone deacetylase 10 (HDAC10) has been suggested in the carcinogenesis of cervical cancer (CC). However, its association with microRNAs (miRNAs) in CC remains exclusive. Hence, this study aims to probe the role of HDAC10 in regulating CC cell proliferation, migration, and invasion and its correlation with the screened-out miRNA target. Microarray analysis and RT-qPCR revealed that HDAC10 expressed poorly in CC cells relative to human immortalized endocervical cells (End1/E6E7). Moreover, HDAC10 downregulation predicted poor survival for patients with CC. Overexpression of HDAC10 reduced CC cell biological activities in vitro and tumor growth and lung metastases in vivo. miR-233, upregulated in CC, was regulated by HDAC10 through histone acetylation, while miR-233 inhibited the effects of HDAC10 overexpression in CC. miR-223 targeted the 3'-UTR of thioredoxin interacting protein (TXNIP) and suppressed its expression, leading to increased CC development in vitro and in vivo. TXNIP overexpression impaired Wnt/ß-catenin pathway activity in CC cells. This article is protected by copyright. All rights reserved.

In-vitro and in-vivo monitoring of gold(III) ions from intermediate metabolite of sodium aurothiomalate through water-soluble ruthenium (II) complex-based luminescent probe.

Real-time monitoring of drug metabolism in vivo is of great significance to drug development and toxicology research. The purpose of this study is to establish a rapid and visual in vivo detection method for the detection of an intermediate metabolite of the gold (I) drug. Gold (I) drugs such as sodium aurothiomalate (AuTM) have anti-inflammatory effects in the treatment of rheumatoid arthritis. Gold(III) ions (Au3+) are the intermediate metabolite of gold medicine, and they are also the leading factor of side effects in the treatment of patients. However, the rapid reduction of Au3+ to Au+ by thiol proteins in organisms limits the in-depth study of metabolism of gold drugs in vivo. Here we describe a luminescence Au3+ probe (RA) based on ruthenium (II) complex for detecting Au3+ in vitro and in vivo. RA with large Stokes shift, good water solubility and biocompatibility was successfully applied to detect Au3+ in living cells and vivo by luminescence imaging, and to trap the fluctuation of Au3+ level produced by gold (I) medicine. More importantly, the luminescent probe was used to the detection of the intermediate metabolites of gold (I) drugs for the first time. Overall, this work offers a new detection tool/method for a deeper study of gold (I) drugs metabolite.

ING4 alleviated lipopolysaccharide-induced inflammation by regulating the NF-κB pathway via a direct interaction with SIRT1.

Sepsis is a complex inflammatory disorder in which high mortality is associated with an excessive inflammatory response. Inhibitor of growth 4 (ING4), which is a cofactor of histone acetyltransferase and histone deacetylase complexes, could negatively regulate this inflammation. However, the exact molecular signaling pathway regulated by ING4 remains uncertain. As a pivotal histone deacetylase, Sirtuin1 (SIRT1), which is widely accepted to be an anti-inflammatory molecule, has not been found to be linked to ING4. This study investigated how ING4 is involved in the regulation of inflammation by constructing lipopolysaccharide (LPS)-induced macrophage and mouse sepsis models. Our results revealed that ING4 expression decreased, whereas the levels of proinflammatory cytokines increased in LPS-stimulated cultured primary macrophages and RAW 264.7 cells. ING4 transfection was confirmed to alleviate the LPS-induced upregulation of proinflammatory cytokine expression both in vitro and in vivo. In addition, ING4-overexpressing mice were hyposensitive to an LPS challenge and displayed reduced organ injury. Furthermore, immunoprecipitation indicated a direct interaction between ING4 and the SIRT1 protein. Moreover, ING4 could block nuclear factor-kappa B (NF-κB) P65 nuclear translocation and restrict P65 acetylation at lysine 310 induced by LPS treatment. These results are the first to clarify that the anti-inflammatory role of ING4 is associated with SIRT1, through which ING4 inhibits NF-κB signaling activation. Our studies provide a novel signaling axis involving ING4/SIRT1/NF-κB in LPS-induced sepsis.

The Akt/FoxO/p27Kip1 axis contributes to the anti-proliferation of pentoxifylline in hypertrophic scars.

Hypertrophic scars (HS) are characterized by the excessive production and deposition of extracellular matrix (ECM) proteins. Pentoxifylline (PTX), a xanthine derived antioxidant, inhibits the proliferation, inflammation and ECM accumulation of HS. In this study, we aimed to explore the effect of PTX on HS and further clarify the mechanism of PTX-induced anti-proliferation. We found that PTX could significantly attenuate proliferation of HS fibroblasts and fibrosis in an animal HS model. PTX inhibited the proliferation of HSFs in a dose- and time-dependent manner, and this growth inhibition was mainly mediated by cell cycle arrest. Transcriptome sequencing showed that PTX affects HS formation through the PI3K/Akt/FoxO1 signalling pathway to activate p27Kip1 . PTX down-regulated p-Akt and up-regulated p-FoxO1 in TGF-ß1 stimulated fibroblasts at the protein level, and simultaneously, the expression of p27Kip1 was activated. In a mouse model of HS, PTX treatment resulted in the ordering of collagen fibres. The results revealed that PTX regulates TGFß1-induced fibroblast activation and inhibits excessive scar formation. Therefore, PTX is a promising agent for the treatment of HS formation.

MCPIP1 regulates RORα expression to protect against liver injury induced by lipopolysaccharide via modulation of miR-155.

Liver injury plays vital roles in the development of inflammation and organ dysfunction during sepsis. MCP-1-induced protein 1 (MCPIP1), as an endoribonuclease, is a critical regulator for the maintenance of immune homeostasis. However, whether MCPIP1 participates in the septic liver injury remains unknown. The aim of this study was to investigate the role of MCPIP1 in lipopolysaccharides-induced liver injury and the underlying modulatory mechanisms. Quantitative real-time polymerase chain reaction and immunoblotting were used to determine proinflammatory cytokines, MCPIP1, retinoid-related orphan receptor α (RORα), miR-155, and related protein from nuclear factor-κB (NF-κB) pathway expression. Dual luciferase reporter assay was used to analyze whether miR-155 regulates RORα transcription. Secretion of inflammatory cytokines into sera in mice were measured by enzyme-linked immunosorbent assay. Hematoxylin and eosin staining, alanine aminotransferase, and aspartate transaminase, assay were used to evaluate liver function. We found that MCPIP1 expression was notably upregulated and significantly downregulated inflammatory cytokine secretion and NF-κB signaling activation in macrophages following exposure to lipopolysaccharide. Moreover, miR-155, lowered by MCPIP1, directly targeted on 3'-untranslated region of RORα to activate an inflammatory response. Importantly, MCPIP1 overexpression in mice alleviated septic liver injury symptoms following lipopolysaccharides stimulation. Collectively, these data highlight MCPIP1/miR-155/RORα axis as a novel modulation of inflammation in liver injury and potential therapeutic target for future research.

MCPIP1 alleviated lipopolysaccharide-induced liver injury by regulating SIRT1 via modulation of microRNA-9.

The severity of sepsis is associated with excessive inflammatory responses. MCP-1 induced protein (MCPIP1) could negatively regulate inflammatory responses by deubiquitinating K48 or K63 polyubiquitins of TNF receptor-associated factors. The function of MCPIP1 in negative regulation of inflammation is known, however, only the exact molecular pathway remains unknown. The aim of this study was to investigate whether and how MCPIP1 is involved in the regulation of lipopolysaccharides (LPS)-induced liver injury. Macrophages and a mouse model were induced by LPS treatment. Several in vitro assays, such as quantitative real-time PCR, immunoblotting, cell transfection, dual luciferase reporter assay, Enzyme-linked immunosorbent assay, and Hematoxylin-Eosin staining assay were used to explore the role of MCPIP1 and the interaction between MCPIP1, Sirtuin 1 (SIRT1), and microRNA-9 (miR-9). We found that the level of MCPIP1 increased and the level of SIRT1 decreased in LPS induced Kupffer cells or RAW 264.7 macrophages. Overexpression of MCPIP1 alleviated cytokine secretion and p65 nuclear translocation. Further study showed that MCPIP1 regulated p65 nuclear translocation by controlling p65 acetylation via promoting SIRT1 expression. Meanwhile, we found that miR-9 could directly regulate SIRT1 transcription by binding to the 3'-Untranslated Region of SIRT1 messenger RNA and that miR-9 was negatively regulated by MCPIP1. Importantly, overexpression of MCPIP1 in vivo could alleviate LPS-induced inflammation responses and liver injury in septic mice. These results demonstrated that MCPIP1 could alleviate inflammation responses and sepsis associated liver injury by promoting the expression of SIRT1, and miR-9 was involved in the MCPIP1-mediated regulation of SIRT1. Collectively, our results provide a possible novel signaling axis involving MCPIP1/miR-9/SIRT1 in LPS-induced septic mice.

Direct Synthesis of Aluminosilicate IWR Zeolite from a Strong Interaction between Zeolite Framework and Organic Template.

A large amount of zeolite structures are still not synthetically available or not available in the form of aluminosilicate currently. Despite significant progress in the development of predictive concepts for zeolite synthesis, accessing some of these new materials is still challenging. One example is the IWR structure as well. Despite successful synthesis of Ge-based IWR zeolites, direct synthesis of aluminosilicate IWR zeolite is still not successful. In this report we show how a suitable organic structure directing agent (OSDA), through modeling of an OSDA/zeolite cage interaction, could access directly the aluminum-containing IWR structure (denoted as COE-6), which might allow access to new classes of materials and thus open opportunities in valuable chemical applications. The experimental results reveal that the COE-6 zeolites with a SiO2/Al2O3 ratio as low as 30 could be obtained. Very interestingly, the COE-6 zeolite has much higher hydrothermal and thermal stabilities than those of the conventional Ge-Al-IWR zeolite. In methanol-to-propylene (MTP) reaction, the COE-6 zeolite exhibits excellent selectivity for propylene, offering a potential catalyst for MTP reaction in the future.

IL-17 Promotes Scar Formation by Inducing Macrophage Infiltration.

Trauma or burn injuries that affect the deep dermis often produce a hypertrophic scar, which limits patients' joint movement and generates an aesthetic problem. Inflammation is believed to be one of the main pathogenic mechanisms. We found that IL-17 was increased in scar tissues from patients with hypertrophic scar compared with normal skin. Recombinant mouse IL-17 was subcutaneously injected into mice that underwent full-thickness excision surgery to investigate the role of IL-17 in scar formation. Mice stimulated with IL-17 showed aggravated fibrogenesis, delayed wound healing, and increased inflammation. In addition, macrophage infiltration was also increased. According to the results of the Transwell assay, IL-17 promoted macrophage infiltration through an indirect mechanism. After depleting macrophages with clodronate liposomes, the effect of IL-17 disappeared. Levels of monocyte chemotactic protein (MCP) 1, MCP2, and MCP3 (together referred to as MCPs) were increased by IL-17 stimulation. Bindarit (an inhibitor of MCPs) was used to verify the role of MCPs. In addition, the Ly6C-low macrophages were responsible for wound fibrogenesis in mice. In this study, we detected the increased levels of IL-17 for the first time and revealed that IL-17 induced the infiltration of a specific subtype of macrophages to aggravate fibrosis through an MCP-dependent mechanism. Thus, our results provide a better understanding of scar formation and new strategies for scar prevention.

ROR alpha protects against LPS-induced inflammation by down-regulating SIRT1/NF-kappa B pathway.

Systemic inflammatory response syndrome (SIRS) is associated with excessive inflammatory response, however, the pathophysiology of inflammation is poorly understood. The retinoid-related orphan receptor α (RORα) is a key inflammatory regulator, but the mechanisms underlying its role remain unclear. The aim of this study was to investigate how RORα was involved in the regulation of inflammatory response. Here we put forward a hypothesis that RORα might negatively regulate inflammatory response by controlling silent information regulator Sirtuin 1 (SIRT1) expression. Stimulation of macrophages in vitro with LPS and LPS administration in vivo were used to explore the function of RORα and the relationship between RORα and SIRT1. We found that the level of RORα was suppressed in macrophages stimulated with LPS and overexpression or knockdown of RORα by transfection with lentivirus or siRNAs significantly decreased or increased, respectively, the pro-inflammatory cytokines IL-1ß, TNF, IL-6 and MCP-1. Importantly, overexpression of RORα suppressed inflammation and alleviated LPS-induced organ injury in vivo. Further study showed that RORα could regulate SIRT1 expression and, consequently, affect deacetyation and nuclear translocation of nuclear factor-kappa B (NF-κB) subunit p65. Moreover, the activation of SIRT1 by its specific agonist, SR1720, could reduce the expression of proinflammatory cytokines in RORα knockdown macrophages stimulated with LPS. In conclusion, we demonstrated that RORα could alleviate LPS-induced inflammation and organ injury both in vivo and in vitro by blocking NF-κB p65 nuclear translocation and restricting acetylation of NF-κB p65 at lysine 310 via the regulation of SIRT1 expression. Targeting RORα might be a promising therapeutic strategy to regulate inflammatory disorders.

Cell-free therapy based on adipose tissue stem cell-derived exosomes promotes wound healing via the PI3K/Akt signaling pathway.

INTRODUCTION: Adipose tissue-derived stem cells (ADSCs) have been shown to enhance wound healing via their paracrine function. Exosomes, as one of the most important paracrine factors, play an essential role in this process. However, the concrete mechanisms that underlie this effect are poorly understood. In this study, we aim to explore the potential roles and molecular mechanisms of exosomes derived from ADSCs in cutaneous wound healing. METHODS: Normal human skin fibroblasts and ADSCs were isolated from patient skin and adipose tissues. ADSCs were characterized by using flow cytometric analysis and adipogenic and osteogenic differentiation assays. Exosomes were purified from human ADSCs by differential ultracentrifugation and identified by electron microscopy, nanoparticle tracking, fluorescence confocal microscopy and western blotting. Fibroblasts were treated with different concentrations of exosomes, and the synthesis of collagen was analyzed by western blotting; the levels of growth factors were analyzed by real-time quantitative PCR (RT-PCR) and ELISA; and the proliferation and migration abilities of fibroblasts were analyzed by real-time cell analysis, CCK-8 assays and scratch assays. A mouse model with a full-thickness incision wound was used to evaluate the effect of ADSC-derived exosomes on wound healing. The level of p-Akt/Akt was analyzed by western blotting. Ly294002, a phosphatidylinositol 3-kinases (PI3K) inhibitor, was used to identify the underlying mechanisms by which ADSC-derived exosomes promote wound healing. RESULTS: ADSC-derived exosomes were taken up by the fibroblasts, which showed significant, dose-dependent increases in cell proliferation and migration compared to the behavior of cells without exosome treatment. More importantly, both the mRNA and protein levels of type I collagen (Col 1), type III collagen (Col 3), MMP1, bFGF, and TGF-ß1 were increased in fibroblasts after stimulation with exosomes. Furthermore, exosomes significantly accelerated wound healing in vivo and increased the level of p-Akt/Akt in vitro. However, Ly294002 alleviated these exosome-induced changes, suggesting that exosomes from ADSCs could promote and optimize collagen deposition in vitro and in vivo and further promote wound healing via the PI3K/Akt signaling pathway. CONCLUSIONS: This study demonstrates that ADSC-derived exosomes can promote fibroblast proliferation and migration and optimize collagen deposition via the PI3K/Akt signaling pathway to further accelerate wound healing. Our results suggest that ADSCs likely facilitate wound healing via the release of exosomes, and the PI3K/Akt pathway may play a role in this process. Our data also suggest that the clinical application of ADSC-derived exosomes may shed new light on the use of cell-free therapy to accelerate full-thickness skin wound healing and attenuate scar formation.

Acute downregulation of miR-199a attenuates sepsis-induced acute lung injury by targeting SIRT1.

MicroRNA-199a (miR-199a) is a novel gene regulator with an important role in inflammation and lung injury. However, its role in the pathogenesis of sepsis-induced acute respiratory distress syndrome (ARDS) is currently unknown. Our study explored the role of miR-199a in sepsis-induced ARDS and its mechanism of action. First, we found that LPS could upregulate miR-199a in alveolar macrophages. Downregulation of miR-199a inhibited the upregulation of inflammatory cytokines in alveolar macrophages and induced the remission of histopathologic changes, the reduction of proinflammatory cytokines, and the upregulation of apoptosis protein expression in an ARDS lung, showing a protective role for miR-199a. We further identified sirtuin 1 (SIRT1) as a direct target of miR-199a in alveolar macrophages, and the expression of SIRT1 was negatively correlated with the level of miR-199a. The protective role of miR-199a downregulation in LPS-stimulated alveolar macrophages and sepsis-induced ARDS could be attenuated by SIRT1 inhibitor. Taken together, these results indicate that downregulation of miR-199a might protect lung tissue against sepsis-induced ARDS by upregulation of SIRT1 through the suppression of excessive inflammatory responses and the inhibition of cellular apoptosis in lung tissue, suggesting its potential therapeutic effects on sepsis-induced ARDS.