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Our previous study demonstrated that gypenosides (Gp) exert protective effects on retinal nerve fibers and axons in a mouse model of experimental autoimmune optic neuritis. However, the therapeutic mechanisms remain unclear. Thus, in this study, a model of oxidative damage in retinal ganglion cells (RGCs) was established to investigate the protective effect of Gp, and its possible influence on oxidative stress in RGCs. Treatment of cells with H 2 O 2 induced RGC injury owing to the generation of intracellular reactive oxygen species (ROS). In addition, the activities of antioxidative enzymes decreased and the expression of inflammatory factors increased, resulting in an increase in cellular apoptosis. Gp helped RGCs to become resistant to oxidation damage by directly reducing the amount of ROS in cells and exerting protective effects against H 2 O 2 -induced apoptosis. Treatment with Gp also reduced the generation of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), and increased nuclear respiratory factor 2 (Nrf-2) levels so as to increase the levels of heme oxygenase-1 (HO-1) and glutathione peroxidase 1/2 (Gpx1/2), which can enhance antioxidation in RGCs. In conclusion, our data indicate that neuroprotection by Gp involves its antioxidation and anti-inflammation effects. Gp prevents apoptosis through a mitochondrial apoptotic pathway. This finding might provide novel insights into understanding the mechanism of the neuroprotective effects of gypenosides in the treatment of optic neuritis.

Casein kinase 2 interacting protein 1 (CKIP1) is a specific interacting protein of the casein kinase 2 (CK2) α subunit, and, by binding CK2 and other proteins, functions as an adaptor to regulate a series of cellular functions. Previous studies suggested that CKIP1 might play an important role in regulating oncogenic activities. However, few studies examining the function of CKIP1 in cancer cells have been performed. The present study aimed to investigate the role of CKIP1 in lung cancer. CKIP1 mRNA expression was detected in 5 human lung cancer cell lines (H-125, H1299, LTEP-A-2, SPC-A-1, and NCL-H446) by semi-quantitative RT-PCR, and in 10 noncancerous lung tissues and 30 non-small lung cancer tissues by real-time quantitative PCR. A lentivirus-mediated small interfering RNA (siRNA) was used to knock down CKIP1 expression in the H1299 cell line. To elucidate the impact of CKIP1 downregulation on H1299 cells, cell proliferation, DNA synthesis, and cell cycle distribution and apoptosis were measured by high content screening assay, BrdU incorporation, and flow cytometric analyses, respectively. CKIP1 mRNA was highly expressed both in H1299 cells and lung cancer tissues. We found that downregulation of CKIP1 resulted in suppression of proliferation and colony-forming ability of H1299 cells, and led to S phase cell cycle arrest and G2 phase promotion, as well as a significant enhancement of H1299 cell apoptosis. Our study indicated that high expression levels of CKIP1 were associated with the development of lung cancer, and that CKIP1 knockdown may block tumor cell growth mainly by promoting cell apoptosis.

Hypericum ascyron L. has been used as a traditional medicine for the treatment of wounds, swelling, headache, nausea and abscesses in China for thousands of years. However, modern pharmacological studies are still necessary to provide a scientific basis to substantiate their traditional use. In this study, the mechanism underlying the antimicrobial effect of the antibacterial activity compounds from H. ascyron L. was investigated. Bioguided fractionation of the extract from H. ascyron L. afforded antibacterial activity fraction 8. The results of cup plate analysis and MTT assay showed that the MIC and MBC of fraction 8 is 5 mg/mL. Furthermore, using Annexin V-FITC/PI, TUNEL labeling and DNA gel electrophoresis, we found that cell death with apoptosis features similar to those in eucaryon could be induced in bacteria strains after exposure to the antibacterial activity compounds from H. ascyron L. at moderate concentration. In addition, we further found fraction 8 could disrupt the cell membrane potential indicate that fraction 8 exerts pro-apoptotic effects through a membrane-mediated apoptosis pathway. Finally, quercetin and kaempferol 3-O-β-(2″-acetyl)-galactopyranoside, were identified from fraction 8 by means of Mass spectrometry and Nuclear magnetic resonance. To our best knowledge, this study is the first to show that Kaempferol 3-O-β-(2″-acetyl)-galactopyranoside coupled with quercetin had significant antibacterial activity via apoptosis pathway, and it is also the first report that Kaempferol 3-O-β-(2″-acetyl)-galactopyranoside was found in clusiacea. Our data might provide a rational base for the use of H. ascyron L. in clinical, and throw light on the development of novel antibacterial drugs., (Copyright © 2015 Elsevier Masson SAS. All rights reserved.)

Objective: To investigate the effect of NSC348884, a nucleophosmin small molecular inhibitor, on the growth of hepatocellular carcinoma cell line HepG2 and its underlying mechanism., Methods: After HepG2 cells were treated by NSC348884 for 4 days, the effect of HepG2 cells on proliferation was measured by methyl thiazolyl tetrazolium (MTT) assay, the expression variation of nucleophosmin oligomer and monomer was measured using Western blotting, and cell apoptotic rate was detected by flow cytometry., Results: The proliferation of HepG2 cells was remarkably inhibited by NSC348884 treatment when the drug concentration ranged from 1 micromol/L to 10 micromol/L (P < 0.05), with a 50% inhibiting concentration of 1.4 micromol/L. After treatment for 24 hours, the expression level of nucleophosmin oligomer decreased obviously while that of nucleophosmin monomer increased (both P < 0.05). After treatment by 1 micromol/L and 2 micromol/L NSC348884, the 24-hour apoptotic rates of HepG2 cells were (13.770 +/- 0.335)% and (19.021 +/- 0.237)%, respectively, which were significantly higher than in the control group (6.950 +/- 0.207)% (P < 0. 05)., Conclusion: NSC348884 can promote the transformation of nucleophosmin oligomer to monomer and thus inhibit the growth of hepatic carcinoma cell line HepG2 in vitro.

microRNA-195(miR-195) is an important member of the micro-15/16/195/424/497 family, and which is activated in multiple diseases, such as cancers, heart failure, and schizophrenia. Mir-195 regulates a plethora of target proteins, which are involved in the cell cycle, apoptosis, proliferation. WEE1, CDK6, and Bcl-2 are confirmed target genes of miR-195 that are involved in miR-195-mediated cell-cycle and apoptosis effects. However, the mechanism of miR-195 action is not completely understood. This review summarizes recent the research progress regarding the roles of miR-195 in the cell cycle and in apoptosis., (Copyright © 2011 Wiley Periodicals, Inc.)

The Snail transcription factor has been described as a strong repressor of E-cadherin and its stable expression induces epithelial-mesenchymal transitions responsible for the acquisition of motile and invasive properties during tumor progression. A fascinating analogy that has been raised is the seemingly similar and shared characteristics of stem cells and tumorigenic cells, which prompted us to investigate whether the mechanisms of the acquisition of invasiveness during tumor progression are also involved in bone marrow stem cells (MSCs). In this study, we examined whether Snail gene expression acts in the mobility, cytoskeleton and anti-apoptosis of MSCs. Cell Transmigration Assay and Western Blotting were performed to evaluate the cell migratory capability and the related Signaling pathways in MSCs transfected with the Snail expression vector of pCAGGSneo-SnailHA (MSCs-Sna), compared with MSCs(MSCs-neo) transducted with the control vector(pCAGGSneo). Actin cytoskeleton by Immunofluorescence and Sub-G1 detection by a FACScan flow cytometer were performed to analyze the cytoskeleton and antiapoptotic capability of MSCs-Sna. Compared with MSCs-neo, MSCs-Sna show significantly more migration in the transwell migration system (P < 0.05). And suppression of PI-3K activation by the specific PI-3K inhibitor, Wortmannin, brought on a reduction in Snail-mediated MSCs migration. In addition, we provide evidences that high expression of Snail inhibited the serum-deprivation triggered apoptosis and cytoskeleton changement of MSCs. These data suggest the possibility of facilitating MSCs migration to injured tissue and subsequent survival and maintenance in the local microenvironment after their transplantation, by investigating and increasing the advantage factors such as Snail high expression in MSCs.

Aim: Overexpression of midkine (MK) has been observed in many malignancies. This aim of this study is to screen for suitable antisense oligonucleotides (ASODN) targeting MK in hepatocellular carcinoma (HCC) cells and evaluate its antitumor activity., Methods: Ten ASODN targeting MK were designed and synthesized. After transfection with ASODN, cell proliferation was analyzed with MTS[3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt] assay. In addition, MK mRNA, protein levels, as well as apoptosis and caspase-3 activity were also examined in HepG2 cells. Cell proliferation was then analyzed after treatment with both ASODN and chemotherapeutic drugs., Results: In this experiment, the ASODN5 among the 10 ASODN showed higher inhibitory activity against proliferation of hepatocellular carcinoma cells in a dose-dependent manner. In HepG2 cells, ASODN5 could significantly reduce the MK mRNA level and protein content. After transfection with ASODN5 for 48 h, accompanied with a decline of survivin and Bcl-2 protein content, a remarkable increase of apoptosis and caspase-3 activity was observed in HepG2 cells. Furthermore, ASODN5 transfer can significantly increase chemosensitivity in HepG2 cells., Conclusion: Antisense oligonucleotides targeting MK shows therapeutic effects on HCC; ASODN5 has the possibility to be developed as an effective antitumor agent.

Aim: To investigate the effect of antisense compounds (AS) targeting human p53 mRNA on radiosensitivity of MCF-7 cells., Methods: Western blotting and RTPCR were used to analyze the protein content and mRNA level. Additionally, cell proliferation, cell cycle and cell apoptosis were all analyzed in irradiated or sham-irradiated cells., Results: Among the five antisense compounds (AS), AS3 was identified to efficiently inhibit p53 mRNA level and protein content. Interestingly, AS3 transfer has little effect on cell proliferation in DU-145 cells (mutant p53) after ionizing radiation (IR). In contrast, a marked increase of cell apoptosis and growth inhibition were observed in MCF-7 cells (wild-type p53), suggesting that AS3 can increase radiosensitivity of MCF-7 cells. Additionally, it was also observed that the transfection of AS3 decreased the fraction of G1 phase cells, and increased the proportion of S phase cells compared to untreated cells 24 h after IR in MCF-7 cell lines., Conclusion: AS3 transfection increases MCF-7 cell apoptosis induced by 5 Gy-radiation, and this mechanism may be closely associated with abrogation of G1 phase arrest.