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Background/Aims: Non-toxic fomitopsis is has been traditionally used in folk medicine in many countries for its anti-inflammatory and anti-vascular disease activities. The present study investigates the antitumor effect of Fomitopsis pinicola (Sw. Ex Fr.) Karst chloroform extract (FPKc) on S180 tumor cells in vitro and in vivo and we determined the underlying mechanisms. Methods: HPLC was employed to analyze the constituents of FPKc. In-vitro 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was performed to quantify the growth inhibition of FPKc; Propidium iodide (PI) exclusion assay and scanning electron microscopy (SEM) were used to observe the damage on the cell membrane and the changes of the cell morphology; Staining with Hoechst 33342/propidium iodide (HO/PI) and the application of the Annexin V-FITC/PI analysis permitted to observe the cell death triggered by FPKc; DNA damage and cell cycle arrest were detected by flow cytometry; Rhodamine 123 (RH123) and Cytochrome C were used as dyes to investigate the alterations of the mitochondria. In-vivo tumor inhibition and mice survival time were determined. Results: The results of the HPLC assay indicated that FPKc might contain DA (dehydroeburiconic acid), PA (pachymic acid), and ES (ergosterol), at percentages of 0.25%, 17.8%, and 10.5%, respectively. Concerning the study of the biological function, the results showed that FPKc exhibited preferential and significant suppression of proliferation on specific cell lines including S180, HL-60, U937, K562, SMMC-7721, and Eca-109 cells, which induced plasma membrane and cell morphology damages, triggering S180 tumor-cells late apoptosis and leading to DNA damage and S phase arrest. Mitochondria were suspected to play a vital role in these changes. In vivo data indicated that FPKc inhibited the solid tumor growth and prolonged the survival time of tumor-bearing mice. Moreover, FPKc provoked only little damage on normal cells in vitro and also on normal tissues in vivo. Conclusion: FPKc inhibited S180 tumor cells growth and prolonged the lifespan of mice. In vitro, we found that FPKc induced S180 tumor cells apoptosis and cell cycle arrest, possibly via the mitochondrial pathway.

Background/Aims: To investigate the associations between the rs1250569 (zinc finger MIZ-type containing 1, ZMIZ1), rs1042522 (tumour protein p53, TP53), and rs10114470 (tumour necrosis factor-like cytokine 1A, TL1A) polymorphisms and the development of inflammatory bowel disease (IBD) in a Chinese (Han) population. We analysed the expression of genes that predispose patients to Crohn’s disease (CD) and ulcerative colitis (UC). Methods: A total of 381 IBD patients and 517 healthy controls were recruited into our study. Polymorphisms at the three loci were genotyped using polymerase chain reaction-ligation detection reactions (PCR-LDR). Genotype-phenotype correlations were analysed. Blood and gut samples were obtained and analysed using quantitative real-time PCR (qRT-PCR), western blot analysis, and immunohistochemistry to investigate the mRNA and protein levels and in situ expression of genes found to predispose patients to IBD. Furthermore, the expression of susceptible genes was further verified using a mouse dextran sulphate sodium (DSS)-induced acute colitis model. Results: No significant association was detected between rs1250569 and rs1042522 genotypes and CD or UC susceptibility. However, the frequency of allele A of rs1250569 was much higher in CD patients than that in healthy controls (55.03% vs. 48.48%, respectively; p = 0.044). The mutation rates at rs10114470 were dramatically lower at both the genotype and allele level in patients than those in healthy controls (p = 0.002 at both the genotype and allele level). Additionally, increased ZMIZ1 and TL1A levels were detected in intestinal samples obtained from both IBD patients and DSS-treated mice. Conclusion: rs1250569 (ZMIZ1) and rs10114470 (TL1A) are two novel loci that indicate susceptibility to IBD in Han-Chinese patients. Consistent with previous studies, TL1A expression levels were higher in Chinese Han IBD patients and DSS-treated mice. Most importantly, we found that ZMIZ1 expression was markedly higher in both IBD patients and mice with experimentally induced colitis, suggesting that ZMIZ1 plays important roles in the pathogenesis of IBD.

Background/Aims: The role of the β3-adrenergic receptor (β3-AR) agonist BRL37344 in atrial fibrillation (AF) structural remodeling and the underlying mechanisms as a therapeutic target were investigated. Methods: Four groups of dogs were evaluated: sham, pacing, β3-AR agonist BRL37344 (β3-AGO), and β3-AR antagonist L748337 (β3-ANT) groups. Dogs in the pacing, β3-AGO and β3-ANT groups were subjected to rapid atrial pacing for four weeks. Atrial structure and function, AF inducibility and duration, atrial myocyte apoptosis and interstitial fibrosis were assessed. Atrial superoxide anions were evaluated by fluorescence microscopy and colorimetric assays. Cardiac nitrate+nitrite levels were used to assess nitric oxide (NO) production. Protein and mRNA expression of β3-AR, neuronal NO synthase (nNOS), inducible NO synthase (iNOS), endothelial NO synthase (eNOS) and guanosine triphosphate cyclohydrolase-1 (GCH-1) as well as tetrahydrobiopterin (BH4) levels were measured. Results: β3-AR was up-regulated in AF. Stimulation of β3-AR significantly increased atrial myocyte apoptosis, fibrosis and atrial dilatation, resulting in increased AF induction and prolonged duration. These effects were attenuated by β3-ANT. Moreover, β3-AGO reduced BH4 and NO production and increased superoxide production, which was inhibited by the specific iNOS inhibitor, 1400w β3-AGO also increased iNOS but decreased eNOS and had no effect on nNOS expression in AF. Conclusions: β3-AR stimulation resulted in atrial structural remodeling by increasing iNOS uncoupling and related oxidative stress. β3-AR up-regulation and iNOS uncoupling might be underlying AF therapeutic targets.

Background: Meconopsis horridula Hook (M. horridula) has been used as a traditional Tibetan medicine to relieve heat and pain as well as mobilize static blood, and it is recognized as a good treatment for bruises. This study is the first trial to evaluate the tumor inhibitory activity of M. horridula extract and its underlying mechanism in the hope of providing evidence to support the anticancer function of M. horridula. Methods and Results: M. horridula extract was cytotoxic to L1210 cells in a dose- and time-dependent manner. SEM (scanning electron microscope) observation revealed obvious morphological changes in L1210 cells after M. horridula treatment. Flow cytometry analysis demonstrated that the extract dose-dependently induced early apoptosis. Additional apoptosis parameters, such as alterations in nuclear morphology and DNA damage, were also observed. Furthermore, M. horridula treatment induced G2/M arrest. M. horridula treatment significantly increased reactive oxygen species (ROS) production, suggesting that ROS are a key factor in M. horridula-induced apoptosis. Volatile constituent detection found 15 abundant chemicals in M. horridula, which may contribute to its anticancer effect. Conclusion: In conclusion, M. horridula extract induced L1210 cell apoptosis and inhibited proliferation through G2/M phase arrest, and ROS were involved in the process.

Background: Sonodynamic therapy (SDT) is an alternative strategy that manages malignancies via the generation of cytotoxic factors during ultrasound-activated sono-sensitive agents. However, the detailed mechanisms are not clear. This study was to identify the cytotoxic effects of ultrasound-activated protoporphyrin IX (PpIX) on U937 cells. Methods: Flow cytometry was performed to detect the time course for PpIX uptake in U937 cells. Sub-cellular localization of PpIX in U937 cells was visualized by inverted confocal laser scanning microscope. Following PpIX-mediated SDT treatment, cell viability was evaluated by the 3-(4, 5- dimethylthiazol-2-yl)-2, 5-diphenyltetrazoliumbromide (MTT) assay; nuclear damage was observed under fluorescent microscope; DNA fragmentation and mitochondrial membrane potential disruption were measured by flow cytometry. The role of reactive oxygen species (ROS) in SDT-induced cell death was also evaluated. Results: We observed that PpIX is mainly localized in the mitochondria, with a maximal uptake within 2 h. Compared with PpIX or ultrasound alone, PpIX plus ultrasound treatment significantly declined cell viability, caused more serious damage of cell morphology, DNA and mitochondria. In the combined treatment group, the intracellular ROS was greatly higher than in other groups; ROS scavenger N-acetylcysteine could effectively rescue the loss of mitochondria membrane potential and cell viability induced by SDT. Conclusion: Taken together, these findings primarily indicated that fatal damage could be induced by PpIX-mediated SDT in U937 cells, and the intracellular ROS was involved during this process.

Background: Porphyrin derivatives have been widely used in photodynamic therapy as effective sensitizers. Protoporphyrin IX (PpIX), a well-known hematoporphyrin derivative component, shows great potential to enhance light induced tumor cell damage. However, PpIX alone could also exert anti-tumor effects. The mechanisms underlying those direct effects are incompletely understood. This study thus investigated the putative mechanisms underlying the anti-tumor effects of PpIX on sarcoma 180 (S180) cells. Methods: S180 cells were treated with different concentrations of PpIX. Following the treatment, cell viability was evaluated by the 3-(4, 5- dimethylthiazol-2-yl)-2, 5-diphenyltetrazoliumbromide (MTT) assay; Disruption of mitochondrial membrane potential was measured by flow cytometry; The trans-location of apoptosis inducer factor (AIF) from mitochondria to nucleus was visualized by confocal laser scanning microscopy; DNA damage was detected by single cell gel electrophoresis; Cell cycle distribution was analyzed by DNA content with flow cytometry; Cell cycle associated proteins were detected by western blotting. Results: PpIX (≥ 1 µg/ml) significantly inhibited proliferation and reduced viability of S180 cells in a dose-dependent manner. PpIX rapidly and significantly triggered mitochondrial membrane depolarization, AIF (apoptosis inducer factor) translocation from mitochondria to nucleus and DNA damage, effects partially relieved by the specific inhibitor of MPTP (mitochondrial permeability transition pore). Furthermore, S phase arrest and upregulation of the related proteins of P53 and P21 were observed following 12 and 24 h PpIX exposure. Conclusion: PpIX could inhibit tumor cell proliferation by induction of DNA damage and cell cycle arrest in the S phase.