ABSTRACT
Objective: To investigate whether ethanol extracts of Hizikia fusiforme could induce apoptosis in human prostate cancer PC3 cells.Methods: Cell viability was evaluated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide. Apoptosis and mitochondrial membrane potential (MMP) were measured using flow cytometry in PC3 cells. DNA damage was assessed by nuclear staining and DNA fragmentation assay. Expressions of apoptosis-associated proteins were determined by Western blotting assays. Activities of caspase-3, -8, and -9 were determined by colorimetric assay. Moreover, intracellular reactive oxygen species (ROS) generation was detected using a flow cytometer and fluorescence microscope. Results: Treatment of PC3 cells with ethanol extracts of Hizikia fusiforme inhibited proliferation, which was associated with induction of apoptosis, and accompanied by increased expression of Fas, Fas-ligand (FasL), Bax and tBid, and decreased expression of Bcl-2. In addition, ethanol extracts of Hizikia fusiforme reduced c-Flip expression and activated caspase-8, -9 and -3, resulting in an increase in poly (ADP-ribose) polymerase (PARP)cleavage. However, in the presence of a pan-caspase inhibitor, ethanol extracts of Hizikia fusiforme-mediated growth inhibition and apoptosis were significantly attenuated. Ethanol extracts of Hizikia fusiforme also destroyed the integrity of mitochondria due to the loss of MMP, leading to cytosolic release of cytochrome c. Moreover, the levels of ROS were markedly increased by treatment with ethanol extracts of Hizikia fusiforme, which was significantly suppressed by the ROS scavenger N-acetyl-L-cysteine. Further investigation of whether ethanol extracts of Hizikia fusiforme-induced apoptosis was related to the generation of ROS was conducted and the results showed that N-acetyl-L-cysteine fully blocked ethanol extracts of Hizikia fusiforme-induced apoptotic events including loss of MMP, activation of caspase-3, the cytosolic release of cytochrome c and cytotoxicity.Conclusions: Ethanol extracts of Hizikia fusiforme have chemopreventive potential via induction of ROS-dependent apoptosis. Therefore, ethanol extracts of Hizikia fusiforme may be useful for developing effective and selective natural sources to inhibit cancer cell proliferation.
ABSTRACT
Objective: To investigate whether ethanol extracts of Hizikia fusiforme could induce apoptosis in human prostate cancer PC3 cells. Methods: Cell viability was evaluated using 3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide. Apoptosis and mitochondrial membrane potential (MMP) were measured using flow cytometry in PC3 cells. DNA damage was assessed by nuclear staining and DNA fragmentation assay. Expressions of apoptosis-associated proteins were determined by Western blotting assays. Activities of caspase-3, -8, and -9 were determined by colorimetric assay. Moreover, intracellular reactive oxygen species (ROS) generation was detected using a flow cytometer and fluorescence microscope. Results: Treatment of PC3 cells with ethanol extracts of Hizikia fusiforme inhibited proliferation, which was associated with induction of apoptosis, and accompanied by increased expression of Fas, Fas-ligand (FasL), Bax and tBid, and decreased expression of Bcl-2. In addition, ethanol extracts of Hizikia fusiforme reduced c-Flip expression and activated caspase-8, -9 and -3, resulting in an increase in poly (ADP-ribose) polymerase (PARP)cleavage. However, in the presence of a pan-caspase inhibitor, ethanol extracts of Hizikia fusiforme-mediated growth inhibition and apoptosis were significantly attenuated. Ethanol extracts of Hizikia fusiforme also destroyed the integrity of mitochondria due to the loss of MMP, leading to cytosolic release of cytochrome c. Moreover, the levels of ROS were markedly increased by treatment with ethanol extracts of Hizikia fusiforme, which was significantly suppressed by the ROS scavenger N-acetyl-L-cysteine. Further investigation of whether ethanol extracts of Hizikia fusiforme-induced apoptosis was related to the generation of ROS was conducted and the results showed that N-acetyl-L-cysteine fully blocked ethanol extracts of Hizikia fusiforme-induced apoptotic events including loss of MMP, activation of caspase-3, the cytosolic release of cytochrome c and cytotoxicity. Conclusions: Ethanol extracts of Hizikia fusiforme have chemopreventive potential via induction of ROS-dependent apoptosis. Therefore, ethanol extracts of Hizikia fusiforme may be useful for developing effective and selective natural sources to inhibit cancer cell proliferation.
ABSTRACT
The immune system is specifically sensitive to oxidative stress induced by ionizing radiation because of its rapid proliferative activity. For this reason, an instructive immune system is one of the best ways to minimize side effects, such immunodeficiency, of gamma radiation. Over the past few decades, several natural plants with antioxidant and immunomodulatory properties have been identified as adjuncts for nontoxic and successful radiotherapy. Hizikia fusiforme extract (HFE) containing plentiful dietary fiber and fucoidan is known for its instructive antioxidant capacity, immunomodulation abilities, and immune activation. In this study, we determined whether HFE protects radiosensitive immune cells from gamma radiation-induced damage. C57BL/6 mice were irradiated with gamma-ray. The effect of HFE on the ionizing radiation damage of immune cells was then evaluated with an MTT assay, 3H-thymidine incorporation assay, and PI staining. We found that HFE stimulated the proliferation of gamma-ray irradiated immune cells without cytotoxic effects. We also observed that HFE not only decreased DNA damage but also reduced gamma radiation-induced apoptosis of the immune cells. Our results suggest that HFE can protect immune cells from gamma-ray damage and may serve as an effective, non-toxic radioprotective agent.
Subject(s)
Animals , Mice , Apoptosis , Dietary Fiber , DNA Damage , Gamma Rays , Immune System , Immunomodulation , Oxidative Stress , Radiation, Ionizing , RadiotherapyABSTRACT
Hizikia fusiforme (sea weed fusiforme) has long been used for food source in this country. This study was performed to evalute the immunomodulative effects of Hizikia fusiforme (sea weed fusiforme) in mouse, using in vivo experiments. In vivo experiment, different concentration (0, 50, 500 mg/kg B.W.) of Hizikia fusiforme water extracts were orally administrated into mouse every other day for two weeks. The proliferation of mouse splenocytes, the production of three cytokines (IL-1beta, IL-6, TNF-alpha) secreted by activated macrophage. Splenocyte proliferation was enhanced in mouse orally administrated with 50 mg/kg B.W. and 500 mg/kg B.W. concentration compared to that of control group. Especially, the highest proliferation of spleoncyte was seen from the mouse orally administrated at the concentration of 50 mg/kg B.W. Also, the mouse of Hizikia fusiforme water extracts supplementation group in the both concentrations showed enhanced levels of cytokine production by activated peritoneal macrophages compared to those in control group. The highest level of cytokine (IL-1beta, IL-6, TNF-alpha) production was observed at 50 mg/kg B.W. supplementation group with LPS stimulation in all cases.