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Background: Metastasis is the most common cause of lethal outcome in various types of cancers. Although the cell proliferation related metabolism rewiring has been well characterized, less is known about the association of metabolic changes with tumor metastasis. Herein, we demonstrate that metastatic tumor obtained a mesenchymal phenotype, which is obtained by the loss of tumor suppressor NDRG2 triggered metabolic switch to glutamine metabolism. Methods: mRNA-seq and gene expression profile analysis were performed to define the differential gene expressions in primary MEC1 and metastatic MC3 cells and the downstream pathways of NDRG2. NDRG2 regulation of Fbw7-dependent c-Myc stability were determined by immunoprecipitation and protein half-life assay. Luciferase reporter and ChIP assays were used to determine the roles of Akt and c-Myc in mediating NDRG2-dependent regulation of ASCT2 in in both tumor and NDRG2-knockout MEF cells. Finally, the effect of the NDRG2/Akt/c-Myc/ASCT2 signaling on glutaminolysis and tumor metastasis were evaluated by functional experiments and clinical samples. Results: Based on the gene expression profile analysis, we identified metastatic tumor cells acquired the mesenchymal-like characteristics and displayed the increased dependency on glutamine utilization. Further, the gain of NDRG2 function blocked epithelial-mesenchymal transition (EMT) and glutaminolysis, potentially through suppression of glutamine transporter ASCT2 expression. The ASCT2 restoration reversed NDRG2 inhibitory effect on EMT program and tumor metastasis. Mechanistic study indicates that NDRG2 promoted Fbw7-dependent c-Myc degradation by inhibiting Akt activation, and subsequently decreased c-Myc-mediated ASCT2 transcription, in both tumor and NDRG2-knockout MEF cells. Supporting the biological significance, the reciprocal relationship between NDRG2 and ASCT2 were observed in multiple types of tumor tissues, and associated with tumor malignancy. Conclusions: NDRG2-dependent repression of ASCT2 presumably is the predominant route by which NDRG2 rewires glutaminolysis and blocks metastatic tumor survival. Targeting glutaminolytic pathway may provide a new strategy for the treatment of metastatic tumors.

BACKGROUND Studies in ApoE knockout mice have shown that pseudolaric acid B (PB) can act as an immunomodulatory drug and attenuate atherosclerosis progression by modulating monocyte/macrophage phenotypes. Our previous study demonstrated that high salt intake could shift the phenotype of monocytes/macrophages to an inflammatory phenotype, and that this shift was related to hypertension and hypertensive left ventricular (LV) remodeling. However, no comprehensive assessment of the effects of PB on hypertensive LV remodeling has been conducted. MATERIAL AND METHODS In this study, RAW264.7 macrophages cultured with different concentrations of NaCl were used to investigate the modulating effects of PB on macrophage phenotype. Furthermore, N-nitro-L-arginine methyl ester hypertensive mice were used to investigate the modulating effects of PB on monocyte phenotype. LV remodeling was investigated by echocardiography. LV morphologic staining (for cardiomyocyte hypertrophy and collagen deposition) was performed at the time of sacrifice. RESULTS The results showed that PB significantly improved the viability of RAW264.7 cells, suppressed their phagocytic and migration abilities, and inhibited their phenotypic shift to M1 macrophages. In addition, the blood pressure of PB-treated mice was significantly decreased relative to that of control mice. Furthermore, after PB treatment, the percentage of Ly6Chi monocytes was significantly decreased while that of Ly6Clo monocytes was apparently increased. Moreover, PB preserved LV function and alleviated myocardial fibrosis and cardiomyocyte hypertrophy as measured at the end of the experimental period. The transfer of monocytes from PB-treated mice to hypertensive mice achieved the same effects. CONCLUSIONS Together, these findings indicate that PB exerts its protective effects on hypertensive LV remodeling by modulating monocyte/macrophage phenotypes and warrants further investigation.

Destruction of endothelial cells (ECs) function is involved in the structural and functional pathophysiological processes of preeclampsia (PE). Vascular endothelial injury may pre-exist for several years in women that develop PE and may pose increased risks for hypertension, coronary artery disease, and type-2 diabetes mellitus. Previous findings showed that Elabela (ELA), the endogenous ligand of the apelin (APJ) receptor expressed mainly on ECs, may play a protective role in early pregnancy and prevent PE. However, the exact functional role and molecular mechanisms of ELA are unclear. Here, we aimed to classify whether and how ELA improves EC function via the ELA-APJ axis. Two human umbilical vein endothelial cell (HUVEC) lines, namely HUVECs and EA.hy926, were treated with ELA, and then their cellular activities were studied by performing CCK-8 tests, scratch-wound analysis, and tube-formation assays. Doses of ELA exceeding 0.01 μmol/L markedly improved the cell viability, migration, and tube formation ability of HUVECs and EA.hy926 cells. Western blot analysis indicated that the above effects caused by ELA were related to upregulation of the APJ receptor and activation of PI3K/Akt signalling. Further verification tests were performed using the PI3K inhibitor wortmannin, and the results illustrated that inhibiting PI3K/Akt signalling blocked the positive effects of ELA on EC function and APJ receptor expression. Taken together, our findings indicate that ELA may alter EC function via the ELA-APJ axis and PI3K/Akt signalling and that ELA shows promise for use in endothelial dysfunction therapy for preventing and treating PE.

We previously discovered that Xiaozhang Tie (XZT) was helpful for cirrhotic ascites, with obvious abdominal distention relief, suggesting that it may improve gastrointestinal (GI) motility. However, the underlying mechanisms of GI motility in cirrhotic ascites are unclear. Here, we aimed to discover explored the effect of XZT on GI motility in animal cirrhotic ascites and probed the action mechanism affecting GI motility by regulating the stem cell factor (SCF)/c-kit pathway in interstitial cells of Cajal (ICCs) and GI hormones. First, rat models of cirrhotic ascites were developed and then divided randomly into the following three subgroups: model control, XZT group, and mosapride group. The efficacy of XZT on treating cirrhotic ascites was evaluated on the basis of ascites weight and volume, 24 h urine volume, and feces water content. GI motility of the cirrhotic model, intestine propulsion, and gastric residue were detected using the migration distance of ink in vivo, and the frequency of contraction and tension of isolated gastric and jejunal muscle strips were measured after incubation with XZT extracts. Serum GI hormone content, including motilin (MTL), substance P (SP), somatostatin (SS), and vasoactive intestinal polypeptide were assayed. Subsequently, ICCs were isolated from jejunum, and primarily cultured ICCs were incubated with and without XZT and SCF. The cell vitality of the ICCs was measured. A whole-cell patch recording technique was used to record the current of K+ and Na+ channels in the ICC membrane. Expressions of c-kit/p-c-kit, p-Akt, p-STAT3, and p-Erk1/2 were detected in vivo and in vitro. The results revealed that XZT significantly reduced ascites weight and increased urine volume and fecal water content in model rats. XZT promoted intestinal motility and increased MTL level but reduced SP and SS levels. It enhanced the current of Na+ and K+ in ICCs and improved c-kit expression and signaling mediator phosphorylation in SCF/c-kit, which was inhibited by imatinib in vitro and downregulated in model rats in vivo. Our study concluded that XZT reduced the amount of ascites and improved intestinal motility in cirrhotic rats, which may be associated with its effect on ascites and was involved in the mechanisms regulating the SCF/c-kit signaling pathway in ICCs and improving gastrointestinal hormone secretion.

Natural killer (NK) cells are known for their ability to kill activated hepatic stellate cells (HSCs), which has been confirmed both in patients and animal models. But the killing function is depressed in period of advanced liver injury. Salvia Miltiorrhiza (SM), a Chinese herbal medicine for invigorating blood circulation and eliminating stasis, is widely used to treat liver fibrosis in clinic. Nevertheless, the immunological mechanism remains unclearly. Here, we put forward the hypothesis that the anti-fibrotic effect of SM is concerned with boosting the activation of hepatic NK cells. Liver fibrosis was induced with carbon tetrachloride (CCl4) and effects of SM on NK cells and HSC (JS-1 cell line, HSC) were investigated in vivo and in vitro. Hepatic NK cells were isolated from C57BL/6 mice, and pre-incubated with SM before they were co-cultured with HSCs. We found that SM increased frequency of NK cells, enhanced activities of NKG2D and Nkp46 on NK cells and inhibited activation of HSCs in vivo and in vitro. SM could promote the activities of NK cells by increasing the expressions of NKG2D and IFN-γ before or after co-cultured with HSCs in vitro. Besides, SM could partially antagonize ASGM-1-induced NK cell depletion and enhance the cell activities to inhibit HSCs activation in vitro. Therefore, our work provided a new insight into the anti-fibrotic mechanism that SM could enhance the activities of NK cell to reduce liver fibrosis in vivo and in vitro.

Endophytic fungi are symbiotic with plants and possess multienzyme systems showing promising metabolite potency with region selectivity and stereoselectivity. The aim of this study was to use these special microorganisms as an in vitro model to mimic the potential mammalian metabolites of a natural iridoid gentiopicroside (GPS, compound 1). The fungi isolated from a medicinal plant, Dendrobium candidum Wall. ex Lindl., were screened for their biotransformation abilities with GPS as the substrate, and one strain with high converting potency was identified as Penicillium crustosum 2T01Y01 on the basis of the sequence of the internal transcribed spacer of the ribosomal DNA region. Upon the optimized incubation of P. crustosum 2T01Y01 with the substrate, seven deglycosylated metabolites were detected by ultraperformance liquid chromatography/quadrupole time of flight mass spectrometry (UPLC/Q-TOF MS). Preparative-scale biotransformation with whole cells of the endophytic fungus resulted in the production of five metabolites, including three novel ones, 5α-(hydroxymethyl)-6β-methyl-3,4,5,6-tetrahydropyrano[3,4- c ]pyran-1(8 H )-one (compound 2), ( Z )-4-(1-hydroxybut-3-en-2-yl)-5,6-dihydropyran-2-one (compound 3), and ( E )-4-(1-hydroxybut-3-en-2-yl)-5,6-dihydropyran-2-one (compound 4), along with two known ones, 5α-(hydroxymethyl)-6β-methyl-1 H ,3 H -5,6-dihydropyrano[3,4- c ]pyran-1(3 H )-one (compound 5) and 5α-(hydroxymethyl)-6α-methyl-5,6-dihydropyrano[3,4- c ]pyran-1(3 H )-one (compound 6), aided by nuclear magnetic resonance and high-resolution mass spectral analyses. The other two metabolites were tentatively identified by online UPLC/Q-TOF MS as 5-hydroxymethyl-5,6-dihydroisochromen-1-one (compound 7) and 5-hydroxymethyl-3,4,5,6-tetrahydroisochromen-1-one (compound 8), and compound 8 is a new metabolite. To test the metabolic mechanism, the β-glucosidase activity of the fungus P. crustosum 2T01Y01 was assayed with ρ-nitrophenyl-β- d -glucopyranoside as a probe substrate, and the pathway of GPS biotransformation by strain 2T01Y01 is proposed. In addition, the hepatoprotective activities of GPS and metabolite compounds 2, 5, and 6 against human hepatocyte line HL-7702 injury induced by hydrogen peroxide were evaluated.

Multiple reports have suggested that reactive oxygen species (ROS) are implicated in hepatic fibrosis and that they are capable of causing hepatocyte apoptosis in hepatic fibrosis by causing oxidative damage to the liver. Thus, the study of antioxidant compounds may shed light on the treatment of hepatic fibrosis. The aim of the current study was to investigate the protective effects of Cordyceps polysaccharide (CPS), a major antioxidative component of Cordyceps militaris, on hydrogen peroxide (H2O2)-induced cell apoptosis. The data showed that CPS markedly inhibited H2O2-induced mitochondrial dysfunction, lowered cell viability, increased the apoptotic rate, boosted ROS production, decreased mitochondrial membrane potential (MMP), reduced the intracellular adenosine triphosphate (ATP) level, increased the Bax/Bcl-2 ratio and promoted cytochrome C (Cyt C) release. These results indicated that CPS protected HL-7702 cells, which are used as the main model of hepatic fibrosis, against H2O2-induced mitochondrial dysfunction by decreasing ROS production and regulating mitochondrial apoptotic signaling through the Cyt C, Bax and Bcl-2 apoptosis-related proteins.

The fragmentation behaviors of the angular- and linear-type coumarins from Peucedanum praeruptorum Dunn and P. decursivum (Miq.) Maxim were simultaneously investigated by HPLC-DAD/ESI-MSn. For more structural identification, the fragment ions were analyzed and some possible fragmentation pathways were proposed. Different positions and numbers of the substituent also led to different fragment behaviors. Two types of coumarins from P. praeruptorum and P. decursivum were structurally elucidated by these techniques. In addition, UV spectra were applied to support the MS analysis. This is the first time that the two types of coumarins from herbal extracts have been differentiated by HPLC-DAD/ESI-MSn. The method further illustrated the importance of the ESI-MSn technique in the identification of different types of coumarins and was applied for the rapid differentiation of the two herbs.