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Renal interstitial fibrosis (RIF) is a crucial pathological change leading to chronic kidney disease (CKD). Currently, no effective medicines have been available for treating it. In our research, we examined the effects of polysaccharides extracted from Balanophora polyandra Griff (BPPs) on kidney fibrosis and epithelial to mesenchymal transition (EMT) in vivo and in vitro, aiming to explore the underlying mechanisms. By using the mice with unilateral urethral obstruction (UUO) as experimental subjects, we examined the medicinal values of BPPs on alleviating RIF. The effects of BPPs were evaluated by examining the histological staining and relative mRNA and protein expression levels of the related genes. The possible underlying mechanisms were further explored with human normal renal proximal tubular epithelia (HK‐2 cells) as in vitro model. In UUO mice, BPP treatment could significantly alleviate interstitial fibrosis through reducing the components (Collagens I, III and IV) of extracellular matrix (ECM), and reducing the activation of fibroblasts producing these components, as revealed by inhibiting the hallmarks (fibronectin and α‐SMA) of fibroblast activation. Furthermore, BPP administration increased the expression levels of matrix metalloproteinases (MMPs) and declined those of tissue inhibitors of metalloproteinases (TIMPs). BPPs markedly ameliorated EMT in both the kidneys of UUO mice and TGF‐β1 treated HK‐2 cells. Moreover, BPP treatment decreased the expression levels of several transcriptional factors involved in regulating E‐cadherin expression, including snail, twist and ZEB1. Additionally, the Hedgehog pathway was found to be closely correlated with renal fibrosis and EMT. Altogether, our results clearly demonstrated that BPP treatment effectively inhibited the Hedgehog pathway both in renal tissues of UUO mice and TGF‐β1‐treated HK‐2 cells. Thus, BPPs ameliorated RIF and EMT in vivo and in vitro via suppressing Hedgehog signalling pathway.

Most genes in evolutionarily complex genomes are expressed to multiple protein isoforms, but there is not yet any simple high‐throughput approach to identify these isoforms. Using an oversimplified top‐down LC–MS/MS strategy, we detected, around the 26‐kD position of SDS‐PAGE, proteins produced from 782 genes in a Cdk4−/− mouse embryonic fibroblast cell line. Interestingly, only 213 (27.24%, about one‐fourth) of these 782 genes have their proteins with a theoretical molecular mass (TMM) 10% smaller or larger than 26 kD, that is, between 23 and 29 kD, the range set as allowed variation in SDS‐PAGE. These 213 proteins are considered as the wild type (WT). The remaining three‐fourths includes proteins from 66 (9.44%) genes with a TMM smaller than 23 kD and proteins from 503 (64.32%, nearly two‐thirds) genes with a TMM larger than 29 kD; these proteins are categorized into a larger‐group or a smaller‐group, respectively, for their appearance at a higher or lower position of SDS‐PAGE. For instance, at this 26‐kD position we detected proteins from the Rps27a, Snrpf, Hist1h4a, and Rps25 genes whose proteins' TMM is 8.6, 9.7, 11.4, and 13.7 kD, respectively, and detected proteins from the Plelc1 and Prkdc genes, whose largest isoform is 533.9 and 471.1 kD, respectively. We extrapolate that many of those proteins migrating unexpectedly in SDS‐PAGE may be isoforms besides the WT protein. Moreover, we also detected a Cdk4 protein in this Cdk4−/− cell line, thus wondering whether some of other gene‐knockout cells or organisms show similar incompleteness of the knockout.

Human mesenchymal stem cells (MSCs) are a heterogeneous subset of nonhematopoietic multipotent stromal stem cells and can differentiate into mesodermal lineage, such as adipocytes, osteocytes, and chondrocytes, as well as ectodermal and endodermal lineages. Human umbilical cord (UC) is one of the most promising sources of MSCs. However, the molecular and cellular characteristics of UC-derived MSCs (UC-MSCs) require extensive investigations, which are hampered by the limited lifespan and the diminished potency over passages. Here, we used the piggyBac transposon-based simian virus 40 T antigen (SV40T) immortalization system and effectively immortalized UC-MSCs, yielding the iUC-MSCs. A vast majority of the immortalized lines are positive for MSC markers but not for hematopoietic markers. The immortalization phenotype of the iUC-MSCs can be effectively reversed by flippase recombinase-induced the removal of SV40T antigen. While possessing long-term proliferation capability, the iUC-MSCs are not tumorigenic in vivo. Upon bone morphogenetic protein 9 (BMP9) stimulation, the iUC-MSC cells effectively differentiate into osteogenic, chondrogenic, and adipogenic lineages both in vitro and in vivo, which is indistinguishable from that of primary UC-MSCs, indicating that the immortalized UC-MSCs possess the characteristics similar to that of their primary counterparts and retain trilineage differentiation potential upon BMP9 stimulation. Therefore, the engineered iUC-MSCs should be a valuable alternative cell source for studying UC-MSC biology and their potential utilities in immunotherapies and regenerative medicine.

SCOPE Obesity increases intracellular lipid accumulation in hepatocytes, which can induce non-alcoholic fatty liver disease (NAFLD). With progression of NAFLD, a sizable fraction of patients develop non-alcoholic steatohepatitis (NASH), eventually leading to cirrhosis and hepatocellular carcinoma (HCC). The mechanism involved in obesity-induced NAFLD remains unclear. Free fatty acids and high-fat diets, which induce hepatocyte senescence, are major risk factors for NAFLD. Therefore in this study, the mechanism of lipotoxicity-induced hepatocyte senescence is investigated. METHODS AND RESULTS The mice are fed a high-fat diet (HFD) and BNL CL.2 cells are treated with palmitate acid (PA) to establish in vivo and in vitro models of lipotoxicity, respectively. SA-β-gal staining is used to analyze the positively stained senescent hepatocytes. The results show that both PA and HFD induce cellular senescence. Real-time-PCR quantitative analysis reveals that miR-34a is significantly upregulated in the liver tissues of the HFD mice and in the PA-treated BNL CL.2 cells. Western blotting analysis shows that cyclin-dependent kinase inhibitor 1 (CDKN1, also known as p21) is upregulated, while cyclin-dependent kinase 6 (CDK6) is downregulated. Further investigation of the mechanism reveals that CDK6 is a target of miR-34a, which binds to the 3' UTR of CDK6 and inhibits its expression. CONCLUSION The findings reveal that miR-34a is upregulated in a high-fat environment in the liver, and induces hepatocyte senescence by targeting CDK6. The miR-34a-CDK6 signaling axis may promote NAFLD development in a high-fat environment and therefore represents a potential target for NAFLD therapy.

Scope The over-activation of the nucleotide-binding domain like receptor protein 3 (NLRP3) inflammasome plays an important role in the pathogenesis of ulcerative colitis (UC). Chlorogenic acid (CGA) exposure is identified as an effective strategy for repressing inflammatory responses. Methods and results In this study, the NLRP3 inflammasome model with LPS/ATP-induced RAW264.7 cells in vitro and dextran-sulfate-sodium (DSS)-induced colitis in mice are used to evaluate the effect of CGA on NLRP3 inflammasome-related signaling. The results suggest that CGA suppressed the expression of NLRP3 inflammasome-related genes (apoptosis-associated speck-like protein containing CARD (ASC), cysteine-requiring aspartate protease (Caspase)-1 p45, Caspase-1 p20, pro-/cleaved-interleukin (IL)-1β, pro-/cleaved-IL-18), p-nuclear factor kappa B (NF-κB) protein, and miR-155 in mice with colitis. Gain- and loss-of-function studies of miR-155 are performed to elucidate its role in inflammation. Moreover, activation of the NF-κB/NLRP3 inflammasome pathway and miR-155 expression is investigated. CGA exposure in lipopolysaccharide (LPS)/adenosine triphosphate (ATP)-stimulated RAW264.7 cells leads to a decrease in p-NK-κB and NLRP3 inflammasome-related proteins, which is dependent on the downregulation of miR-155 expression. Conclusions These findings indicate that CGA prevented colitis by downregulating miR-155 expression and inactivating the NF-κB/NLRP3 inflammasome pathway in macrophages. The current study has promising therapeutic implications in the treatment of UC.

Crop root water uptake has strong correlations with transpiration and yield. An accurate prediction of crop root water uptake can benefit understanding of the law of transpiration and soil water movement. Under water and salinity stress, maize root water uptake will decrease because of soil water pressure and osmotic head. Usually such reduction of water uptake can be expressed by models such as the additive model and the multiplicative model. Based on a field irrigation experiment, we calculated spring maize root water uptake in this study by setting different combinations of water amount and saline concentration based on the water balance method. One additive model and four multiplicative models of root water uptake were calibrated and verified in order to simulate the impact of water and salt stress on root water uptake. The result shows that multiplicative models are better than the additive model in simulating the experimental data from different treatments. Therefore, the multiplicative model is recommended as the optimal model of root water uptake of spring maize under water and salinity stress in the arid region of north-west China. Copyright © 2015 John Wiley & Sons, Ltd. Resume Le prelevement racinaire des cultures a de fortes correlations avec la transpiration et le rendement. Une prevision precise du prelevement racinaire peut beneficier de la comprehension des lois de transpiration et de mouvement de l'eau dans le sol. Le mais en condition de stress hydrique et salin diminue le prelevement racinaire a cause de la charge hydraulique et de la pression osmotique. Habituellement, une telle reduction du prelevement peut etre exprimee par certains modeles, tels que le modele additif ou le modele multiplicatif. Base sur une experience au champ et des methodes de quantification du bilan hydrique, nous avons calcule le prelevement racinaire du mais en mettant en differentes combinaisons de doses d'irrigation pour differentes concentrations en sels. Un modele additif et quatre modeles multiplicatifs de prelevement ont ete etalonnes et verifies afin de simuler l'impact du stress sur le prelevement, ceci au printemps. Le resultat montre que les modeles multiplicatifs sont meilleurs que le modele additif et reproduisent les donnees experimentales de differents traitements. Par consequent, le modele multiplicatif est recommande comme modele optimal de prelevement racinaire du mais de printemps sous stress hydrique et salin, dans la region aride du nord-ouest de la Chine.

BACKGROUND The aim of this study was to investigate the influence of a combination of selenium-enriched green tea polysaccharides (Se-GTP) and Huo-ji polysaccharides (HJP) on the immune function and antioxidant activity in mice. RESULTS The results showed that the indices of spleen and thymus were markedly increased, and the activity of natural killer (NK) cell was promoted in mice treated with the combination of Se-GTP and HJP. The combined treatment of Se-GTP and HJP also reduced the content of tumour necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in splenocytes. In addition, the activities of glutathione peroxidase (GPx) and superoxide dismutase (SOD) were remarkably enhanced, and malondialdehyde (MDA) levels were significantly reduced in mice treated with combination of Se-GTP and HJP. Furthermore, the combined treatment of Se-GTP and HJP increased nuclear factor erythroid 2-related factor (Nrf2) expression at mRNA and protein levels in splenocytes. The effects of the combination treatment of Se-GTP and HJP in mice were stronger than with Se-GTP or HJP treatment alone. CONCLUSION Our study suggests that the combined administration of Se-GTP and HJP can synergistically improve immune function and decrease the oxidative stress by enhancing the mechanisms involved in the clearance of free radicals. © 2015 Society of Chemical Industry