Solar-steam generation provides an economically efficient pathway to produce clean water by using solar irradiation as an energy source. While this strategy is highly suitable for portable and small ...scale water purification for individuals, families and those living in remote areas, the development of highly efficient and flexible photothermal materials which can be easily transported for storage and deliver is required. In this study, a commercial degreasing cotton, photothermal CuS yolk-shell nanocages and agarose were combined to produce a highly flexible photothermal aerogel which delivered a high energy efficiency (94.9%) for solar-steam generation under 1.0 sun irradiation, corresponding to a water evaporation rate of 1.63 kg m−2 h−1. The preparation of the photothermal aerogel can be easily scaled up due to the simplicity of the applied casting method. The obtained aerogel showed excellent stability for solar steam generation with no degradation in performance after at least 15 cycles. The salinity of the clean water produced during solar-thermal desalination of seawater was only 0.54 ppm. The raw materials of cotton, agarose and CuS are all cost effective, thus this flexible photothermal aerogel has showed great potential for practical application in portable solar-thermal evaporators.
A new flexible photothermal aerogel composed of commercial cotton, CuS yolk-shell nanocages and agarose was readily prepared by a simply casting method. The photothermal aerogel shows excellent energy efficiency of 94.9% for solar-steam generation. Display omitted
•A highly flexible photothermal aerogel were prepared for highly efficient solar-steam generation.•Cost effective commercial cotton, CuS yolk-shell nanocages and agarose were used as raw materials.•The photothermal aerogel delivers a high energy efficiency of 94.9% for solar-steam generation under 1.0 sun.•The photothermal aerogel is suitable for seawater desalination driven by sun light.
Background and Aims
Hepatocytes undergo profound metabolic rewiring when primed to proliferate during compensatory regeneration and in hepatocellular carcinoma (HCC). However, the metabolic control ...of these processes is not fully understood. In order to capture the metabolic signature of proliferating hepatocytes, we applied state‐of‐the‐art systems biology approaches to models of liver regeneration, pharmacologically and genetically activated cell proliferation, and HCC.
Approach and Results
Integrating metabolomics, lipidomics, and transcriptomics, we link changes in the lipidome of proliferating hepatocytes to altered metabolic pathways including lipogenesis, fatty acid desaturation, and generation of phosphatidylcholine (PC). We confirm this altered lipid signature in human HCC and show a positive correlation of monounsaturated PC with hallmarks of cell proliferation and hepatic carcinogenesis.
Conclusions
Overall, we demonstrate that specific lipid metabolic pathways are coherently altered when hepatocytes switch to proliferation. These represent a source of targets for the development of therapeutic strategies and prognostic biomarkers of HCC.
HCV hijacks many host metabolic processes in an effort to aid viral replication. The resulting hepatic metabolic dysfunction underpins many of the hepatic and extrahepatic manifestations of chronic ...hepatitis C (CHC). However, the natural history of CHC is also substantially influenced by the host metabolic status: obesity, insulin resistance and hepatic steatosis are major determinants of CHC progression toward hepatocellular carcinoma (HCC). Direct-acting antivirals (DAAs) have transformed the treatment and natural history of CHC. While DAA therapy effectively eradicates the virus, the long-lasting overlapping metabolic disease can persist, especially in the presence of obesity, increasing the risk of liver disease progression. This review covers the mechanisms by which HCV tunes hepatic and systemic metabolism, highlighting how systemic metabolic disturbance, lipotoxicity and chronic inflammation favour disease progression and a precancerous niche. We also highlight the therapeutic implications of sustained metabolic dysfunction following sustained virologic response as well as considerations for patients who develop HCC on the background of metabolic dysfunction.
Background and Aims
Lenvatinib is an effective drug in advanced HCC. Its combination with the anti‐PD1 (programmed cell death protein 1) immune checkpoint inhibitor, pembrolizumab, has generated ...encouraging results in phase Ib and is currently being tested in phase III trials. Here, we aimed to explore the molecular and immunomodulatory effects of lenvatinib alone or in combination with anti‐PD1.
Approach and Results
We generated three syngeneic models of HCC in C57BL/6J mice (subcutaneous and orthotopic) and randomized animals to receive placebo, lenvatinib, anti‐PD1, or combination treatment. Flow cytometry, transcriptomic, and immunohistochemistry analyses were performed in tumor and blood samples. A gene signature, capturing molecular features associated with the combination therapy, was used to identify a subset of candidates in a cohort of 228 HCC patients who might respond beyond what is expected for monotherapies. In mice, the combination treatment resulted in tumor regression and shorter time to response compared to monotherapies (P < 0.001). Single‐agent anti‐PD1 induced dendritic and T‐cell infiltrates, and lenvatinib reduced the regulatory T cell (Treg) proportion. However, only the combination treatment significantly inhibited immune suppressive signaling, which was associated with the TGFß pathway and induced an immune‐active microenvironment (P < 0.05 vs. other therapies). Based on immune‐related genomic profiles in human HCC, 22% of patients were identified as potential responders beyond single‐agent therapies, with tumors characterized by Treg cell infiltrates, low inflammatory signaling, and VEGFR pathway activation.
Conclusions
Lenvatinib plus anti‐PD1 exerted unique immunomodulatory effects through activation of immune pathways, reduction of Treg cell infiltrate, and inhibition of TGFß signaling. A gene signature enabled the identification of ~20% of human HCCs that, although nonresponding to single agents, could benefit from the proposed combination.
Advances in fluorescence imaging coupled with the generation of near infrared probes have significantly improved the capabilities of non-invasive, real-time imaging in whole animals. In this study we ...were able to overcome a limitation of in vivo fluorescence imaging and have established a dual cell tracking method where two different cell types can be monitored according to the spectral signature of the cell labelling fluorophore. Using a mouse model of acute liver injury, we have characterised the in vivo migration patterns of wild type and transgenic neutrophils with impaired chemotaxis. Here, we were able to demonstrate that IVIS provides a sensitive multiplexing technology to differentiate two different cell populations based on the spectral signature of the cell labelling fluorophores. This spectral unmixing methodology has the potential to uncover multidimensional cellular interactions involved in many diseases such as fibrosis and cancer. In vivo spectral un-mixing provides a useful tool for monitoring multiple biological process in real-time in the same animal.
Precision cut liver slices (PCLSs) retain the structure and cellular composition of the native liver and represent an improved system to study liver fibrosis compared to two‐dimensional mono‐ or ...co‐cultures. The aim of this study was to develop a bioreactor system to increase the healthy life span of PCLSs and model fibrogenesis. PCLSs were generated from normal rat or human liver, or fibrotic rat liver, and cultured in our bioreactor. PCLS function was quantified by albumin enzyme‐linked immunosorbent assay (ELISA). Fibrosis was induced in PCLSs by transforming growth factor beta 1 (TGFβ1) and platelet‐derived growth factor (PDGFββ) stimulation ± therapy. Fibrosis was assessed by gene expression, picrosirius red, and α‐smooth muscle actin staining, hydroxyproline assay, and soluble ELISAs. Bioreactor‐cultured PCLSs are viable, maintaining tissue structure, metabolic activity, and stable albumin secretion for up to 6 days under normoxic culture conditions. Conversely, standard static transwell‐cultured PCLSs rapidly deteriorate, and albumin secretion is significantly impaired by 48 hours. TGFβ1/PDGFββ stimulation of rat or human PCLSs induced fibrogenic gene expression, release of extracellular matrix proteins, activation of hepatic myofibroblasts, and histological fibrosis. Fibrogenesis slowly progresses over 6 days in cultured fibrotic rat PCLSs without exogenous challenge. Activin receptor‐like kinase 5 (Alk5) inhibitor (Alk5i), nintedanib, and obeticholic acid therapy limited fibrogenesis in TGFβ1/PDGFββ‐stimulated PCLSs, and Alk5i blunted progression of fibrosis in fibrotic PCLS. Conclusion: We describe a bioreactor technology that maintains functional PCLS cultures for 6 days. Bioreactor‐cultured PCLSs can be successfully used to model fibrogenesis and demonstrate efficacy of antifibrotic therapies.
Abstract
Synaptophysin is expressed on fibrogenic hepatic myofibroblasts. C1–3 is a single chain human antibody (scAb) that binds specifically to synaptophysin on hepatic myofibroblasts, providing a ...targeting vector for novel in vivo imaging agents of chronic liver disease. C1–3 and a negative control scAb, CSBD9, were radiolabelled with zirconium-89 via desferrioxamine chelation to enable non-invasive molecular imaging with positron emission tomography (PET). DFO-scAb conjugates were characterised by gel electrophoresis (SDS-PAGE) and MALDI-TOF spectrometry, and
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Zr-labelled with high radiolabelling efficiency (99%).
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ZrZr-DFO-C1–3 exhibited high in vitro stability (> 99%) in mouse and human sera over 3 days at 25 and 37 °C. Activated hepatic myofibroblasts incubated with
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ZrZr-DFO-C1–3 displayed significantly higher internalised activity (59.46%, P = 0.001) compared to the
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ZrZr-DFO-CSBD9 control, indicating synaptophysin-mediated uptake and high binding specificity of
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ZrZr-DFO-C1–3. Mice with CCl
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-induced acute liver damage exhibited significantly higher liver uptake of
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ZrZr-DFO-C1–3, compared to controls, confirmed by both Cerenkov imaging and ex vivo gamma counting (4.41 ± 0.19%ID/g, P < 0.0001). CCl
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-induced liver damage and the number of hepatic myofibroblasts was confirmed by αSMA staining of liver sections. These findings indicate that
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ZrZr-DFO-C1–3 has promising utility as a PET imaging agent for non-invasive detection of hepatic myofibroblasts following acute liver injury.
The progression of fibrosis in chronic liver disease is dependent upon hepatic stellate cells (HSCs) transdifferentiating to a myofibroblast-like phenotype. This pivotal process is controlled by ...enzymes that regulate histone methylation and chromatin structure, which may be targets for developing anti-fibrotics. There is limited pre-clinical experimental support for the potential to therapeutically manipulate epigenetic regulators in fibrosis. In order to learn if epigenetic treatment can halt the progression of pre-established liver fibrosis, we treated mice with the histone methyltransferase inhibitor 3-deazaneplanocin A (DZNep) in a naked form or by selectively targeting HSC-derived myofibroblasts via an antibody-liposome-DZNep targeting vehicle. We discovered that DZNep treatment inhibited multiple histone methylation modifications, indicative of a broader specificity than previously reported. This broad epigenetic repression was associated with the suppression of fibrosis progression as assessed both histologically and biochemically. The anti-fibrotic effect of DZNep was reproduced when the drug was selectively targeted to HSC-derived myofibroblasts. Therefore, the in vivo modulation of HSC histone methylation is sufficient to halt progression of fibrosis in the context of continuous liver damage. This discovery and our novel HSC-targeting vehicle, which avoids the unwanted effects of epigenetic drugs on parenchymal liver cells, represents an important proof-of-concept for epigenetic treatment of liver fibrosis.
Fibrosis results in progressive deposition of scar tissue leading to cirrhosis. The histone methyltransferase EZH2 regulates the activity of scar-forming myofibroblasts. By developing a liposome vehicle decorated with an antibody selective for myofibroblasts, we demonstrate that in vivo pharmacological targeting of myofibroblast EZH2 is sufficient to block fibrosis progression in chronic liver disease.
During chronic kidney disease (CKD) there is a dysregulation of extracellular matrix (ECM) homeostasis leading to renal fibrosis. Lysosomal proteases such as cathepsins (Cts) regulate this process in ...other organs, however, their role in CKD is still unknown. Here we describe a novel role for cathepsins in CKD. CtsD and B were located in distal and proximal tubular cells respectively in human disease. Administration of CtsD (Pepstatin A) but not B inhibitor (Ca074-Me), in two mouse CKD models, UUO and chronic ischemia reperfusion injury, led to a reduction in fibrosis. No changes in collagen transcription or myofibroblasts numbers were observed. Pepstatin A administration resulted in increased extracellular urokinase and collagen degradation. In vitro and in vivo administration of chloroquine, an endo/lysosomal inhibitor, mimicked Pepstatin A effect on renal fibrosis. Therefore, we propose a mechanism by which CtsD inhibition leads to increased collagenolytic activity due to an impairment in lysosomal recycling. This results in increased extracellular activity of enzymes such as urokinase, triggering a proteolytic cascade, which culminates in more ECM degradation. Taken together these results suggest that inhibition of lysosomal proteases, such as CtsD, could be a new therapeutic approach to reduce renal fibrosis and slow progression of CKD.
Neutrophils are the most abundant inflammatory cells at the earliest stages of wound healing and play important roles in wound repair and fibrosis. Formyl peptide receptor 1 (FPR-1) is abundantly ...expressed on neutrophils and has been shown to regulate their function, yet the importance of FPR-1 in fibrosis remains ill defined. FPR-1-deficient (fpr1-/-) mice were protected from bleomycin-induced pulmonary fibrosis but developed renal and hepatic fibrosis normally. Mechanistically, we observed a failure to effectively recruit neutrophils to the lungs of fpr1-/- mice, whereas neutrophil recruitment was unaffected in the liver and kidney. Using an adoptive transfer model we demonstrated that the defect in neutrophil recruitment to the lung was intrinsic to the fpr1-/- neutrophils, as C57BL/6 neutrophils were recruited normally to the damaged lung in fpr1-/- mice. Finally, C57BL/6 mice in which neutrophils had been depleted were protected from pulmonary fibrosis. In conclusion, FPR-1 and FPR-1 ligands are required for effective neutrophil recruitment to the damaged lung. Failure to recruit neutrophils or depletion of neutrophils protects from pulmonary fibrosis.
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