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Hepatocellular carcinoma (HCC) is an invasive malignant neoplasm with a poor prognosis. The development of chemoresistance severely obstructs the chemotherapeutic efficiency of HCC treatment. Therefore, understanding the mechanisms of chemoresistance is important for improving the outcomes of patients with HCC. Eukaryotic translation initiation factor 5A2 (eIF5A2), which is considered to be an oncogene, has been reported to mediate chemoresistance in various types of cancer; however, its precise role in HCC remains unclear. Accumulating evidence has suggested that autophagy serves a dual role in cancer chemotherapy. The present study aimed to investigate the role of autophagy in eIF5A2-mediated doxorubicin resistance in HCC. High expression levels of eIF5A2 in human HCC tissues were observed by immunohistochemistry using a tissue microarray, which was consistent with the results of reverse transcription-quantitative PCR analysis in paired HCC and adjacent healthy tissues. HCC patient-derived tumor xenograft mouse model was used for the in vivo study, and knockdown of eIF5A2 effectively enhanced the efficacy of doxorubicin chemotherapy compared with that in the control group. Notably, eIF5A2 served as a repressor in regulating autophagy under chemotherapy. Silencing of eIF5A2 induced doxorubicin sensitivity in HCC cells by triggering lethal autophagy. In addition, 5-ethynyl-2′-deoxyuridine, lactate dehydrogenase release assay and calcein-AM/PI staining were used to determine the enhanced autophagic cell death induced by the silencing of eIF5A2 under doxorubicin treatment. Suppression of autophagy attenuated the sensitivity of HCC cells to doxorubicin induced by eIF5A2 silencing. The results also demonstrated that knockdown of the Beclin 1 gene, which is an autophagy regulator, reversed the enhanced autophagic cell death and doxorubicin sensitivity induced by eIF5A2 silencing. Taken together, these results suggested eIF5A2 may mediate the chemoresistance of HCC cells by suppressing autophagic cell death under chemotherapy through a Beclin 1-dependent pathway, and that eIF5A2 may be a novel potential therapeutic target for HCC treatment.

Stroke ranks as the second leading cause of disability and death globally. Trigger receptors expressed on myeloid cells (TREM) −1 are responsible for the activation of the innate immune response and also play a critical role in inflammation. In this study, we reported the contribution of TREM-1 after ischemic damage in a rat middle cerebral artery occlusion (MCAO) model. This study also demonstrated that TREM-1 expression was upregulated following cerebral infarction in rats. TREM-1 inhibition was determined using its selective inhibitor, LP17, which indicated a neuroprotective effect on cerebral infarction damage. The findings revealed that inhibition of TREM-1 by administering LP17 improved cerebral damage and decreased ischemic areas and brain water contents. Moreover, LP17 decreased MCAO-induced microglial activation and neurodegeneration, evidenced by a reduction in the expression of microglial Iba-1 and FJ-B positive cells, and reversed neuronal loss. Besides, the contribution of LP17 to ischemic neuronal damage may be associated with a decrease in the production of pro-inflammatory cytokines, and enhanced production of anti-inflammatory cytokine IL-10. Both in vivo and in vitro studies showed that inhibiting TREM-1 attenuated ROS accumulation, lipid per-oxidation (LPO) contents such as malondialdehyde (MDA) and enhanced the superoxide dismutase (SOD) activity after ischemia. Inhibiting TREM-1 alleviated inflammation and pyroptosis found in MCAO rats. This was achieved through the inhibition of the levels of NLRP3, caspase-1, ASC (an apoptosis-associated speck-like protein containing a CARD) and gasdermin D. These results confirmed that inhibiting TREM-1 protects against ischemia-induced neuronal damage and alleviates microglial mediated neuro-inflammation by reducing oxidative stress and pyroptosis. Therefore, blocking TREM-1 expression provides an effective intervention for improving ischemic stroke.

Previous studies have shown that 5,2′,4′-trihydroxy-6,7,5′-trimethoxyflavone (TTF1) is the primary anticancer constituent of the traditional Chinese medicinal plant Sorbaria sorbifolia (SS), which has been applied to treat cancer in China. In this study, we investigated the in vitro and in vivo antitumor effects and biological mechanisms of small-molecule TTF1 nanoparticles (TTF1-NPs). The effects of TTF1-NPs on cell growth and apoptosis were investigated using human hepatoma cells. The molecular changes associated with the effects of TTF1-NPs were analyzed by immunocytochemistry and Western blot analysis. The in vivo effect of TTF1-NPs was investigated using the HepG2 tumor xenograft model. We found that TTF1-NPs exhibited antitumor effects in vitro accompanied by induction of apoptosis in human hepatoma cells. Mechanistically, our data showed that TTF1-NPs induced apoptosis via endoplasmic reticulum stress (ERS) pathway in hepatoma cells. Moreover, inhibition of ERS activation blocked TTF1-NP-induced apoptosis in HepG2 cells. Finally, TTF1-NPs inhibited the growth of HepG2 xenograft tumors. Taken together, our results demonstrated that TTF1-NP-induced apoptosis was mediated at least in part by the ERS pathway and thus inhibited hepatoma tumor growth.

Previous studies have reported that memantine presents evidence of therapeutic benefits in several animal models of ischemic stroke and neurodegenerative diseases. However, the effect of memantine on secondary damage in the ipsilateral thalamus after focal cortical infarction remains undefined. Present study investigated whether memantine has a protective effect on secondary damage in the ipsilateral thalamus after focal cerebral infarction in rats. At 24 h after distal middle cerebral artery occlusion (MCAO), rats in the memantine and vehicle groups were intraperitoneal injected with memantine and isopycnic vehicle, respectively, was once daily administered for consecutive 7 days. Infarct size was evaluated through Nissl staining and sensory decline determined using adhesive removal test. Secondary thalamic damage was assessed using Nissl staining and immunofluorescence 8 days after MCAO. Immunoboltting was used to identify tau and apoptosis-associated proteins in the ipsilateral thalamus after MCAO. Results revealed that memantine ameliorated sensory decline compared to the vehicle controls. Subsequently, tau phosphorylated at threonine 231 (p-tau-231), glycogen synthase kinase3βpY216 (GSK3βpY216) and protein phosphatase 2A (PP2ApY307) were reduced by memantine, causing greater reduction in neuronal loss and inhibition of reactive astrogliosis in the ipsilateral ventroposterior thalamic nucleus (VPN) compared with the vehicle groups. In addition, increase in secondary damage-induced TUNEL-positive cells was blunted by memantine, as demonstrated by the significant reduction in expression of apoptosis-associated proteins. Our results suggest that memantine has a neuro-protective effect on secondary damage in the ipsilateral thalamus following MCAO by inhibiting the activity of GSK3βpY216/PP2ApY307 and down regulating the levels of p-tau-231 protein.

This study was designed to investigate the effect of 5,2’,4’-trihydroxy-6,7,5’-trimethoxy flavone nanoparticle(TTF1-NP) on inducing apoptosis of implanted tumour cells in nude mice and the mechanism of endoplasmic reticulum stress pathway. The implanted hepatoma model was established in nude mice, and used to test the drug TTF1-NP in five groups(vehicle, 5 μmol·kg(-1) TTF1-NP, 10 μmol·kg(-1) TTF1-NP, 20 μmol·kg(-)1TTF1-NP and adriamycin). The nude mice were killed after the treatment to determine the tumor growth inhibition rate(IR). Morphological changes of implanted tumor cells were observed by HE staining; apoptosis of tumor cells was detected by TUNEL; the protein expression of GRP78, p-JNK and caspase 12 were analyzed using immunocytochemistry staining and Western blotting. We tested the effects of TTF1-NP on implanted Hep G-2 cell tumor growth in nude mice. TTF1-NP-treated mice showed volume of tumor smaller than that of the vehicle-treated mice. The tumor mass of the TTF1-NP-treated mice were significantly reduced than those of the vehicle-treated mice. In addition, the tumor growth rate of the TTF1-NP-treated mice was significantly lower than that of the vehicle-treated mice, and the tumor growth inhibition ratio of the TTF1-NP-treated mice was significantly higher than that of the vehicle-treated mice. TTF1-NP exhibited an inhibitory effect on implanted tumor cells in the model. The IR was 51.2%, 54.2%, 61.8% and 65.9%, respectively. In comparison with the vehicle group, the treated groups exhibited alteration in cell morphology and apoptosis of tumor cells, and expression of GRP78, p-JNK and caspase 12, which were observed by immunocytochemistry staining and Western blotting. Taken together, our results suggest that TTF1-NP induces apoptosis of implanted tumor cells in nude mice and the main mechanism is related to activation of endoplasmic reticulum stress.

Although excessive plasma adenosine is detrimental in sickle cell disease (SCD), the molecular mechanism underlying elevated circulating adenosine remains unclear. Here we report that the activity of soluble CD73, an ectonucleotidase producing extracellular adenosine, was significantly elevated in a murine model of SCD and correlated with increased plasma adenosine. Mouse genetic studies demonstrated that CD73 activity contributes to excessive induction of plasma adenosine and thereby promotes sickling, hemolysis, multiorgan damage, and disease progression. Mechanistically, we showed that erythrocyte adenosine 5'-monophosphate-activated protein kinase (AMPK) was activated both in SCD patients and in the murine model of SCD. AMPK functions downstream of adenosine receptor ADORA2B signaling and contributes to sickling by regulating the production of erythrocyte 2,3-bisphosphoglycerate (2,3-BPG), a negative allosteric regulator of hemoglobin-O2 binding affinity. Preclinically, we reported that treatment of α,β-methylene adenosine 5'-diphosphate, a potent CD73 specific inhibitor, significantly decreased sickling, hemolysis, multiorgan damage, and disease progression in the murine model of SCD. Taken together, both human and mouse studies reveal a novel molecular mechanism contributing to the pathophysiology of SCD and identify potential therapeutic strategies to treat SCD.

The cytotoxic T lymphocyte (CTL) response plays a key role in controlling viral infection, but only a few epitopes within the HTNV glycoprotein (GP) that are recognized by CTLs have been reported. In this study, we identified one murine HTNV GP-derived H2-Kb-restricted CTL epitope in C57BL/6 mice, which could be used to design preclinical studies of vaccines for HTNV infection. First, 15 8-mer peptides were selected from the HTNV GP amino acid sequence based on a percentile rank of

Astrocytes were reported to show neuroprotective effects on neurons, but there was no direct evidence for a functional relationship between astrocytes and neural stem cells (NSCs). In this experiments, we examined neuronal differentiation of NSCs induced by protoplasmic and fibrous astrocytes in a co-culture model respectively. Two types of astrocytes and NSCs were isolated from E13 to 15 cortex of rats. The neuronal differentiation of NSCs was examined after co-culture with two kinds of astrocytes. There were more neuronal marker β-tublin III positive cells from NSCs co-cultured with protoplasmic astrocytes. However the differentiated neurons, whether co-cultured with protoplasmic astrocytes or fibrous astrocytes, both expressed glutamate AMPA receptor subunit GluR2 protein and exhibited biological electrical reactivity after stimulated by glutamine. Therefore, these findings indicated that two types of astrocytes could induce the differentiation of NSCs and also possibly induce functional maturation of differentiated neurons, among which protoplasmic astrocytes have the ability to promote neuronal differentiation of NSCs compared with fibrous astrocytes.

A high affinity polyclonal antibody-based enzyme linked immunosorbent assay (ELISA) was developed for the quantification of zeranol in bovine urine. On the basis of urine matrix studies, the optimized dilution factors producing insignificant matrix interference were selected as 1:5 in pretreatment. In the improved ELISA, the linear response range was between 0.02 and 1 microg/ml, and the detection limit was 0.02 microg/ml for the assay. The overall recoveries and the coefficients of variation (CVs) were in the range of 82% to approximately 127% and 3.5% to approximately 8.8%, respectively. Thirty-six bovine urine samples spiked with zeranol (ranging from 0.2 to 10 microg/ml) were detected by the ELISA and liquid chromatography (LC) method, and good correlations were obtained between the two methods (R(2)=0.9643). We conclude that this improved ELISA is suitable tool for a mass zeranol screening and can be an alternative for the conventional LC method for zeranol in bovine urine.

Natural curcumin (1), demethoxycurcumin (2) and bisdemethoxycurcumin (3) isolated from Curcuma longa (turmeric), and synthetic curcumin analogs (A(1-7), B(1-7), C(1-6) and D(1-7)) were evaluated in vitro for the alpha-glucosidase inhibitory activity via UV and circular dichroism (CD) spectroscopy. The results indicated that natural curcuminoid compound 3 showed a remarkable inhibitory effect with IC(50) of 23.0 microM, and the synthetic compounds A(2), B(2), C(2) and D(2) showed potent inhibitory effects with IC(50) of 2.8, 2.6, 1.6 and 8.2 microM, respectively. Kinetic study exhibited that the mechanism of alpha-glucosidase inhibition of both 3 and C(2) was non-competitive. The structure activity relationship revealed that the ortho dihydroxyl groups could form a more tight interaction with alpha-glucosidase to exert more potential inhibitory activities.

The proto-oncogene c-Met was found to express on human laryngeal carcinoma Hep-2 cell line in previous research. In the present study, the author further examined whether inhibition of c-Met by RNA interference (RNAi) might inhibit biologic activity of Hep-2 cell line in vitro and proliferation using a murine laryngeal carcinoma model.RNAi plasmid that can express small interfering RNA targeting c-Met or siRNA that did not match any known human coding mRNA(control siRNA plasmid)was designed, constructed, and transfected into Hep-2 cell line by using cationic liposome Lipofectamine2000 as transfecting agent. In vitro, the transfection efficacy was tested by RT-PCR and Western Blot method, then elected the most inhibitive c-Met-siRNA sequence. Cell proliferation, movement and invasion were studied using MTT, cell migration assay and cell invasion assay, respectively. The Hep-2 cells were transplanted into nude mice, then the time of tumor formation and growth were observed. After tumor formation, c-Met-siRNA was given as the anti-tumor therapy. Expression of c-Met, MMP-9 and VEGF were detected by Western Blot method.After the pSilencer2.0/c-Met-shRNA recombinant plasmid transfection into laryngeal carcinoma Hep-2 cells, the expression of mRNA and protein of c-Met decreased significantly in Hep-2 cells. On the 35th day after tumor vaccination, the tumor volume was (138 ± 27) mm³ in c-Met-siRNA transfection group, Which was diminished significantly in contrast with control group (P0.01). The expression of c-Met, MMP-9 and VEGF in the tumor of experiment group was decreased significantly, respectively (P0.05).The results indicated that c-Met-siRNA can down-regulate the expression of c-Met and markedly inhibit laryngeal carcinoma Hep-2 cell proliferation, movement and invasion and the growth of transplantation tumor of nude mice. The siRNA expressing plasmid mediated gene therapy might be a new strategy in targeting molecular therapy of cancer of larynx.