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Renal fibrosis is the common histopathological feature of chronic kidney diseases (CKD), and there is increasing evidence that epigenetic regulation is involved in the occurrence and progression of renal fibrosis. N-myc downstream-regulated gene 2 (NDRG2) is significantly down-regulated in renal fibrosis, the mechanism of which remains unclear. Previous studies have confirmed that the inhibition of NDRG2 expression in tumor cells is related to hyper-methylation, mainly regulated by DNA methyltransferases (DNMTS). Herein, we explored the expression of NDRG2 and its epigenetic regulatory mechanism in renal fibrosis. The results showed that the expression of NDRG2 was significantly inhibited in vivo and in vitro, while the overexpression of NDRG2 effectively alleviated renal fibrosis. Meanwhile, we found that the expression of DNMT1/3A/3B was significantly increased in hypoxia-induced HK2 cells and Unilateral Ureteral Obstruction (UUO) mice accompanied by hyper-methylation of the NDGR2 promoter. Methyltransferase inhibitor (5-AZA-dC) corrected the abnormal expression of DNMT1/3A/3B, reduced the methylation level of NDRG2 promoter and restored the expression of NDRG2. The upstream events that mediate changes in NDRG2 methylation were further explored. Reactive oxygen species (ROS) are important epigenetic regulators and have been shown to play a key role in renal injury due to various causes. Accordingly, we further explored whether ROS could induce DNA-epigenetic changes of the expression of NDRG2 and then participated in the development of renal fibrosis. Our results showed that mitochondria-targeted antioxidants (Mito-TEMPO) could reverse the epigenetic inhibition of NDRG2 in a DNMT-sensitive manner, showing strong ability of DNA demethylation, exhibiting epigenetic regulation and anti-fibrosis effects similar to 5-AZA-dC. More importantly, the anti-fibrotic effects of 5-AZA-dC and Mito-TEMPO were eliminated in HK2 cells with NDRG2 knockdown. These findings highlight that targeting ROS-mediated hyper-methylation of NDRG2 promoter is a potentially effective therapeutic strategy for renal fibrosis, which will provide new insights into the treatment of CKD.

Glycosaminoglycans (GAGs), such as heparin, heparan sulfate and chondroitin sulfate, are playing important roles in various biological processes. Due to the laborious work of organic or enzymatic total synthesis of GAGs, different approaches, including glycopolymers, dendrimers, etc., have been developed to mimic the structures and bioactivities of GAGs, but the syntheses can still be difficult. In the current study, a new format of GAG mimetic structure, supramolecularly assembled polymers, have been easily prepared by mixing fluorenylmethoxycarbonyl-diphenylalanine (Fmoc-FF) and sulfated glyco-modified fluorenylmethoxy derivatives (FGS and FG3S). The self-assembly behavior of these polymers into different structural formats of nanoparticles, nanofibers and macroscopic hydrogels upon adjusted concentrations and composite ratios have been detailed studied. The nanofibers modified with highly sulfated glycol groups (FG3S/Fmoc-FF) showed strong promotion effect for cell proliferation, which efficiency was even similar to that of natural heparin, higher than nanoparticles or non-/low-sulfated glyco-modified nanofibers. Moreover, the supramolecular polymers were further made into hydrogels that capable of 3D cell culture. This study provided a novel and efficient approach for GAG mimicking, showing great potential for tissue engineering related applications.

There is a high demand for the development of functional foods formulated with health-promoting carotenoids. Curcumin (Cur) is one of the most promising carotenoids, but its application in functional foods especially drinks is limited due to its poor water solubility, low stability and bioavailability. Nanocarriers have shown great potential to solve these problems. In this work, Cur was loaded into nanocarriers made of self-assembly of partially hydrolyzing α-lactalbumin (α-lac). Cur functional dairy drinks were developed by adding Cur-loaded nanocarriers (nanocarriers (Cur)) into dairy drinks, and their colloidal stability and bioavailability were evaluated. The results showed that Cur exhibited intestine-responsive release behavior due to the unique nanospheres micellar structure that the hydrophobic cutting sites were buried in the core and not easily accessible to pepsin. In addition, the α-lac nanocarriers improved the stability of Cur against ultraviolet light. Furthermore, static and accelerated stability experiments showed that nanocarriers (Cur) dairy drinks possessed excellent colloidal stability. According to the sensory evaluation, the addition of nanocarriers (Cur) to dairy drinks significantly improved the perception score of stability and overall assessment. Moreover, nanocarriers (Cur) dairy drinks showed the highest Cur bioavailability. Therefore, the embedding via α-lac nanocarriers is feasible for applying Cur to functional dairy drinks and has broad prospects in the food industry.

6-Formylindolo(3,2-b)carbazole (FICZ), a high-affinity aryl hydrocarbon receptor (AhR) ligand, plays a protective role in inflammatory bowel disease (IBD) through activation of AhR. Interleukin-6 (IL-6) induced intestinal epithelial barrier dysfunction is involved in the pathological process of IBD. In this study, we investigated the protective effects of FICZ on IL-6 induced intestinal epithelial barrier injury. Our data show that AhR activation by FICZ ameliorated colonic inflammation, decreased IL-6 and claudin-2 expression, and maintained intestinal barrier function in a mouse model of dextran sulphate sodium (DSS)-induced colitis. In Caco-2 and T84 intestinal epithelial cells, FICZ also prevented the increase of intestinal epithelial permeability and claudin-2 expression induced by IL-6. Depletion of AhR expression by small interfering (si)RNA reversed FICZ induced decrease of claudin-2. Furthermore, IL-6 induced upregulation of claudin-2 was required for increased caudal-related homeobox 2 (CDX-2) and hepatocyte-nuclear factor (HNF)-1α. However, FICZ repressed the increase of CDX-2 and HNF-1α expression induced by IL-6. These results reveal the protective effects of FICZ on IL-6 induced disruption of intestinal epithelial barrier function through suppressing the expression of claudin-2. In addition, CDX-2 and HNF-1α are involved in the regulation of claudin-2 after IL-6 and FICZ treatment. Therefore compounds related to AhR ligands may be potential pharmaceutical agents to treat IBD.

Erbium (Er) has been used as a novel dopant to modify FeMn/TiO2 catalyst for the selective catalytic reduction of NO with NH3. The optimized ErxFeMn/TiO2 catalyst exhibited excellent catalytic performance at low temperature under a high space velocity of 30,000 h−1. The temperature window for NO conversion efficiency higher than 80% ranged from 100° to 240°C. The catalysts were characterized using XRD, BET, H2-TPR, NH3-TPD, XPS, TGA and In-situ DRIFT. The results showed that Er modification on FeMn/TiO2 catalysts increased the specific surface area, dispersion, reducibility, Mn4+ concentration, and especially the concentration of Lewis acid sites and surface chemisorbed labile oxygen, resulting in an excellent catalytic performance at low temperature. Additionally, Er modification also restrained the formation of sulfate and/or bisulfate salts, which improved the resistance to SO2 and H2O of the catalyst.

Soil moisture often governs the exchange of water between the land surface and the atmosphere and, as a result, has a profound effect on the global water and energy cycles. With the launch of the two new L-band satellite missions tasked with retrieving surface soil moisture (i.e., Soil Moisture and Ocean Salinity (SMOS) and Soil Moisture Active/Passive (SMAP) missions), new possibilities exist for quasi-global soil moisture monitoring. Here, new soil moisture estimates (CLDAS-BPNN), generated by fusing a land surface model soil moisture product (CLDAS) using in-situ observations via a Back Propagation Neural Network (BPNN) method, are used to evaluate four satellite-derived soil moisture products (SMOS-L3, SMOS-IC, SMAP_L3_SM_P, and SMAP_L3_SM_P_E) over the highly irrigated Huai River Basin in China. Results indicate that the post-processing of CLDAS (to generate CLDAS-BPNN) reduces soil moisture errors (particularly bias) and preserves temporal correlations with in-situ observations. Due to extensive irrigation present in the basin, CLDAS-BPNN soil moisture time series have weak seasonal differences and the spatial distribution of their means does not reflect known precipitation patterns. Based on the validation of SMOS and SMAP soil moisture retrievals against CLDAS-BPNN, several key findings can be obtained. First, SMAP retrievals are recommended for locations possessing both valid SMOS and SMAP retrievals. However, SMOS provides generally better spatial support than SMAP. Second, the four satellite retrievals present no significant seasonal variation in time-varying errors, and larger soil moisture underestimation is observed in winter than in summer. Finally, all four satellite products exhibit degraded accuracy in mountainous and forested areas of the Huai River Basin relative to flatter terrain in the Huaibei plain.

Background This research is dedicated to investigating the effects and potential mechanism of action of the aryl hydrocarbon receptor on the intestinal mucosal immune system in dextran sulfate sodium (DSS)-induced colitis. Methods Colitis was induced by the administration of 3% DSS to wild-type C57BL/6J mice for 7 days. 6-formylindolo(3, 2-b)carbazole (FICZ), an endogenous agonist of the aryl hydrocarbon receptor (AhR), was given intraperitoneally on a daily basis beginning 2 days after the start of DSS administration. The mice were weighed and assessed, and colon tissues were measured. Intraepithelial lymphocytes (IELs) were isolated from the colon and examined by flow cytometry and quantitative real-time PCR. Results FICZ ameliorated DSS-induced colitis, resulting in a reduced disease activity index and improvement in the histology and length of the colon. Colitis reduced the percentage and number of CD8αα+TCRαβ+ IELs. FICZ prevented the reduction in the numbers of CD8αα+TCRαβ+ IELs by upregulating the expression of the IL-15 receptor and the aryl hydrocarbon receptor (AhR), and attenuating the apoptotic rate of CD8αα+TCRαβ+ IELs. Finally, IL-10 was increased and IFN-γ was decreased in CD8αα+TCRαβ+ IELs by FICZ administration in DSS-induced colitis. Conclusions The results suggest that AhR activation ameliorated DSS-induced acute colitis, in a manner that is associated with the local expansion and functions of CD8αα+TCRαβ+ IELs in acute colitis. The findings indicate that AhR-related ligands might be targeted as novel drug targets for IBD.

Abundant eclogite-type rutile deposits have recently been discovered along the North Qaidam ultrahigh-pressure (UHP) metamorphic belt in China. The identified titanium reserves exceed 3 million tons and range in grade from 1.0% to 4.5%. The rutile deposits of economic interest are found within two types of eclogite . However, the origin and original geodynamic setting of the two types of rutile-bearing eclogites remain controversial. This study therefore investigates ore and mineralization bodies belonging to the two types by way of detailed field work and geochronological, geochemical and Sr–Nd–Hf isotopic compositional analysis, taking the Dulan eclogite-type rutile deposit as its case study. Type-1 rutile-bearing eclogites enclosed in granitic gneisses are found to have Neoproterozoic protolith ages of 845 ± 4 Ma and an eclogite-facies metamorphic age of ca. 433 Ma. Their high TiO2, TFe2O3, and P2O5 contents cannot have been produced by rutile-formation during UHP metamorphism but could have arisen through the accumulation of ilmenite and apatite in a high-Ti protolith. They have ocean-island basalt (OIB)-like trace element patterns, with enrichment in light rare-earth elements (LREEs) and high field strength elements (HFSEs) (Nb, Ta, Zr, and Hf). The Hf isotopic compositions of the residual magmatic zircon cores in Type-1 rutile-bearing eclogites (eHf (845) = +1.4 to +6.0, TDM = 1.2–1.5 Ga) indicate that their parental magmas were derived from the Proterozoic mantle. However, they show initial 87Sr/86Sr values of 0.71059–0.71326 and eNd (845) values of −1.5 to −2.5, suggesting significant crustal contamination. Thus, the Type-1 rutile-bearing eclogites may have originated through partial melting of an OIB-type mantle plume source during the Neoproterozoic rifting of the Rodinia supercontinent. In contrast, the Type-2 rutile-bearing eclogites, which are hosted in a mafic–ultramafic ophiolitic complex, have protolith ages of 449 ± 3 Ma and eclogite-facies metamorphic ages of ca. 435–433 Ma. Correlations between the whole-rock MgO and the major and trace element contents of Type-2 rutile-bearing eclogites suggest that they are derived from cumulates with alternating olivine and pyroxene-rich and ilmenite-rich layers. They have mid-ocean-ridge basalt (MORB) and OIB-like trace element patterns, indicating extensive fractional crystallization and the possibility that there were multiple injections of magma during the formation of the protolith. Meanwhile, the +0.6 to +4.3 eNd (449) values and −1.8 to +11.8 eHf (449) values of the Type-2 rutile-bearing eclogites indicate that the protoliths may have been generated by partial melting of a mantle wedge source metasomatized by slab-derived components. The short interval (ca. 14 my) between magma generation and eclogite-facies metamorphism, in combination with the type of rock assemblage within which they are found, indicates that the Type-2 rutile-bearing eclogites originated in a supra-subduction zone (SSZ) ophiolite. Type-1 and Type-2 rutile-bearing eclogites have similar eclogite-facies metamorphic ages of ca. 435–433 Ma, indicating that the Type-1 and SSZ-related Type-2 protoliths were incorporated into a subduction melange that was dragged down the subduction channel and underwent eclogite-facies metamorphism via subduction of the Qaidam Block, eventually forming eclogite-type rutile deposits.