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Although various advancements in radical surgery and neoadjuvant chemotherapy have been developed in treating osteosarcoma (OS), their clinical prognosis remains poor. A synthetic chemical compound, 3-hydroxylflavone, that is reported to regulate ROS production is known to inhibit human bone osteosarcoma cells. However, its role and mechanism in human OS cells remains unclear. In this study, we have determined the potential of 3-Hydroxy-2-phenylchromone (3-HF) against OS using human osteosarcoma (HOS) cells. Our previous studies showed that Zipper sterile-alpha-motif kinase (ZAK), a kinase member of the MAP3K family, was involved in various cellular events such as cell proliferation and cell apoptosis, and encoded two transcriptional variants, ZAK&alpha, and &beta, In this study, we show that 3-HF induces the expression of ZAK and thereby enhances cellular apoptosis. Using gain of function and loss of function studies, we have demonstrated that ZAK activation by 3-HF in OS cells is confined to a ZAK&beta, form that presumably plays a leading role in triggering ZAK&alpha, expression, resulting in an aggravated cancer apoptosis. Our results also validate ZAK&beta, as the predominant form of ZAK to drive the anticancer mechanism in HOS cells.

Curcumin, a popular yellow pigment of the dietary spice turmeric, has been reported to inhibit cell growth and to induce apoptosis in a wide variety of cancer cells. Although numerous studies have investigated anticancer effects of curcumin, the precise molecular mechanism of action remains unidentified. Whereas curcumin mediates cell survival and apoptosis through mitogen-activated protein kinase (MAPK) and nuclear factor-kappa B (NF-κB) signaling cascades, its impact on the upstream regulation of MAPK is unclear. The leucine-zipper and sterile-α motif kinase alpha (ZAKα), a mitogen-activated protein kinase kinase kinase (MAP3K), activates the c-Jun N-terminal kinase (JNK) and NF-κB pathway. This paper investigated the prospective involvement of ZAKα in curcumin-induced effects on cancer cells. Our results suggest that the antitumor activity of curcumin is mediated via a mechanism involving inhibition of ZAKα activity.

Cardiomyopathy involves changes in the myocardial ultra-structure, hypertrophy, apoptosis, fibrosis and inflammation. Angiotensin II (AngII) stimulates the expression of insulin like-growth factors (IGF-2) and IGF-2 receptor (IGF-2R) in H9c2 cardiomyoblasts and subsequently leads to apoptosis. Estrogen receptors protect cardiomyocytes from apoptosis and fibrosis. Tanshinone IIA (TSN), a main active ingredient from Danshen, has been shown to protect cardiomyocytes from death caused by different stress signals. Estrogen receptor α (ER) is required for the rapid activation of the IGF-1R signaling cascade. This study aimed to investigate whether TSN protected H9c2 cardiomyocytes from AngII-induced activation of IGF-2R pathway and hypertrophy via ERs. We found that AngII caused the reduction in IGF-1R phosphorylation and the elevation of β-catenin and IGF-2R levels. This was reversed by increasing doses of TSN and of caspase-3 and ERK1/2 phosphorylation mediated by ERs. The phytoestrogen significantly attenuated AngII-induced apoptosis and suppressed the subsequent cardiac remodeling effect. Therefore, TSN reduced the AngII-induced activation of β-catenin and IGF-2R pathways, apoptosis and cardiac remodeling via ERs in H9c2 cardiomyoblasts.

// Wei-Jen Ting 1,2 , Jaw-Ji Yang 3 , Chia-Hua Kuo 4 , Zi-Jun Xiao 5 , Xin-Ze Lu 5 , Yu-Lan Yeh 6,7 , Cecilia-Hsuan Day 8 , Su-Ying Wen 9,10 , Vijaya PadmaViswanadha 11 , Chong-He Jiang 1 , Wei-Wen Kuo 12,* and Chih-Yang Huang 2,13,14,* 1 The Sixth Affiliated Hospital of Guangzhou Medical University, Guangdong, China 2 Graduate Institute of Basic Medical Science, China Medical University, Taichung, Taiwan 3 Institute of Medicine, School of Dentistry, Chung-Shan Medical University, Taichung, Taiwan 4 Department of Sports Sciences, University of Taipei, Taipei, Taiwan 5 National Taichung First Senior High School, Taichung, Taiwan 6 Department of Pathology, Changhua Christian Hospital, Changhua, Taiwan 7 Jen-Teh Junior College of Medicine, Nursing and Management, Miaoli, Taiwan 8 Department of Nursing, Mei Ho University, Pingtung, Taiwan 9 Graduate Institute of Clinical Medical Science, China Medical University, Taichung, Taiwan 10 Department of Dermatology, Taipei City Hospital, Renai Branch, Taipei, Taiwan 11 Department of Biotechnology, Bharathiar University, Coimbatore, India 12 Department of Biological Science and Technology, China Medical University, Taichung, Taiwan 13 Graduate Institute of Chinese Medical Science, China Medical University, Taichung, Taiwan 14 Department of Health and Nutrition Biotechnology, Asia University, Taichung, Taiwan * These authors have contributed equally to this paper Correspondence to: Chih-Yang Huang, email: // Keywords : environmental tobacco smoke (ETS); Sirt-1; autophagy; Gerotarget Received : November 02, 2015 Accepted : April 16, 2016 Published : May 04, 2016 Abstract Recently, a survey by the Centers for Disease Control and Prevention (CDC) reported that nearly 90% of U.S. adult smokers began smoking at the age of 18. This demonstrates that the exposure to environmental tobacco smoke (ETS) of youngsters today is changing from passive smoking to active smoking (direct inhalation of tobacco). In the current study, an investigation of ETS exposure in young C57BL mice was conducted. After 6 weeks of ETS exposure, the Sirt-1 protein level was decreased and cardiac autophagy was increased in C57BL mice. Furthermore, the IGF2R cardiac hypertrophy signaling pathway was also triggered, although cardiac apoptosis and hypertrophy were not induced. Youngsters’ desire to look more mature is one of the psychological factors that impacts smoking amongst young people. Our results suggest that though ETS exposure might cause cardiac autophagy amongst youngsters, the loss of the longevity Sirt-1 protein and the increase in IGF2R cardiac hypertrophy signaling could still promote heart diseases that are age-specific.

Sterile alpha motif (SAM)- and leucine-zipper-containing kinase (ZAK) plays a role in the regulation of cell cycle progression and oncogenic transformation. The ZAK gene generates two transcript variants, ZAKα and ZAKβ, through alternative splicing. In this study, we identified that ZAKα proteins were upregulated in tumor tissues, whereas ZAKβ proteins were mostly expressed in corresponding normal tissues. The ectopically expressed ZAKβ proteins in cancer cells inhibited cancer cell proliferation as well as anchorage-independent growth. The ZAKβ:ZAKα protein ratio played a role in the regulation of the cyclic adenosine monophosphate (cAMP) signaling pathway, whereas high ZAKβ protein levels led to the activation of cAMP response element binding protein 1 (CREB1) and exerted antitumor properties. Overexpression of ZAKβ or CREB1 cDNAs in cancer cells inhibited anchorage-independent growth and also reduced the levels of cyclooxygenase 2 (Cox2) and β-catenin proteins. Cancer cells treated with doxorubicin (Doxo) resulted in the switching from the expression of ZAKα to ZAKβ and also inhibited cancer cell growth in soft agar, demonstrating that pharmacological drugs could be used to manipulate endogenous reprogramming splicing events and resulting in the activation of endogenous antitumorigenic properties. We showed that the two ZAK transcript variants, ZAKα and ZAKβ, had opposite biological functions in the regulation of tumor cell proliferation in that ZAKβ had powerful antitumor properties and that ZAKα could promote tumor growth.

Background: Coffee is a major dietary source of polyphenols. Previous research found that coffee had a protective effect on periodontal disease. In this study, we aimed to investigate whether coffee extract and its primary phenolic acid, chlorogenic acid, affect the growth and protease activity of a periodontopathogen Porphyromonas gingivalis (P. gingivalis). Methods: Coffee extract and chlorogenic acid were prepared by a two-fold serial dilution. The turbid metric test and plate count method were used to examine the inhibitory effects of chlorogenic acid on P. gingivalis. The time-kill assay was used to measure changes in the viability of P. gingivalis after exposure to chlorogenic acid for 0&ndash, 24 h. The protease activity of P. gingivalis was analyzed using the optical density of a chromogenic substrate. Results: As a result, the minimum inhibitory concentration (MIC) of chlorogenic acid was 4 mg/mL, and the minimum bactericidal concentration was 16 mg/mL. Chlorogenic acid at concentrations above MIC resulted in a longer-lasting inhibitory effect on P. gingivalis viability and significantly reduced associated protease activity. The coffee extract showed antibacterial activity as observed by the disk diffusion test, whereas these inhibitory effects were not affected by different roast degrees of coffee. Conclusions: Collectively, our novel findings indicate that chlorogenic acid not only has antimicrobial activity but also reduced the protease activity of P. gingivalis. In addition, coffee extract inhibits the proliferation of P. gingivalis, which may partly be attributed to the effect of chlorogenic acid.

It is unclear whether cardiac hypertrophy and hypertrophy-related pathways will be induced by long-term intermittent hypoxia. Thirty-six Sprague–Dawley rats were randomly assigned into three groups: normoxia, and long-term intermittent hypoxia (12% O2, 8 h per day) for 4 weeks (4WLTIH) or for 8 weeks (8WLTIH). Myocardial morphology, trophic factors and signalling pathways in the three groups were determined by heart weight index, histological analysis, Western blotting and reverse transcriptase-polymerase chain reaction from the excised left ventricle. The ratio of whole heart weight to body weight, the ratio of left ventricular weight to body weight, the gross vertical cross-section of the heart and myocardial morphological changes were increased in the 4WLTIH group and were further augmented in the 8WLTIH group. In the 4WLTIH group, tumour necrosis factor-α(TNFα), insulin-like growth factor (IGF)-II, phosphorylated p38 mitogen-activated protein kinase (P38), signal transducers and activators of transcription (STAT)-1 and STAT-3 were significantly increased in the cardiac tissues. However, in the 8WLTIH group, in addition to the above factors, interleukin-6, mitogen-activated protein kinase (MEK)5 and extracellular signal-regulated kinase (ERK)5 were significantly increased compared with the normoxia group. We conclude that cardiac hypertrophy associated with TNFα and IGF-II was induced by intermittent hypoxia. The longer duration of intermittent hypoxia further activated the eccentric hypertrophy-related pathway, as well as the interleukin 6-related MEK5–ERK5 and STAT-3 pathways, which could result in the development of cardiac dilatation and pathology.

The chemopreventive property of garlic is related in part to its induction of phase II detoxification enzymes. In the present study, we investigated the modulatory effect of 3 garlic organosulfur compounds, i.e., diallyl sulfide (DAS), diallyl disulfide (DADS), and diallyl trisulfide (DATS), which differ in their number of sulfur atoms, on the gene expression of the class of glutathione S-transferase (GSTP). Hepatocytes isolated from male Sprague-Dawley rats were cultured with 50 -200 mol/L of DAS, DADS, or DATS for 24 h. DADS and DATS increased GST activity toward ethacrynic acid by 40 and 66%, respectively (P 0.05). Moreover, both garlic allyl sulfides dose dependently induced GSTP mRNA and protein expression. DATS increased the protein level more than DADS (P 0.05). In contrast, DAS did not affect the activity or the protein or mRNA levels of this phase II drug-metabolizing enzyme. In Clone 9 liver cells, the pTA-luciferase reporter assay showed that luciferase activity in DADS- and DATS-treated cells was 2.8- and 3.9-fold higher than that in control cells, respectively (P 0.05). Again, luciferase activity was not affected by treatment with DAS. Deletion of 2.7 to 2.6 kb in the GSTP promoter region, which contains the GSTP enhancer (GPE) I element, abolished the upregulation of GSTP transcription by DADS and DATS. Deletion of GPE II, however, did not affect the induction of reporter activity. In conclusion, the effectiveness of 3 garlic allyl sulfides on GSTP expression was related to the number of sulfur atoms in the molecules, and GPE I was responsible for this upregulation. J. Nutr. 135: 2560 -2565, 2005.

The regulation of genes by amino acids is attracting increasing attention. In the present study, we investigated the restriction of expression of the pi class of glutathione S-transferase (GST Yp) by sulfur amino acids. Hepatocytes isolated from male Sprague-Dawley rats were cultured with L-15-based medium containing low (LSAA; 0.1 mmol/L L-methionine and 0.1 mmol/L L-cysteine) or high (HSAA; 0.5 mmol/L L-methionine and 0.2 mmol/L L-cysteine) amounts of sulfur amino acids for up to 6 d. Cellular protein contents did not differ between LSAA- and HSAA-treated cells over the entire period. In contrast, glutathione concentrations were suppressed by the LSAA medium and on d 6 were only 20% of those of HSAA-treated cells (P < 0.05). As shown by immunoblot analysis, GST Yp protein levels were greater in LSAA-treated cells than in HSAA-treated cells (P < 0.05). The induction of GST Yp by L-methionine and L-cysteine restriction was not affected by insulin and dexamethasone, but the latter suppressed GST Yp expression (P < 0.05). LSAA increased GST Yp mRNA levels and GST activity toward ethacrynic acid (P < 0.05). GST Yp induction occurred only in cells with a limited supply of L-methionine; restriction of L-isoleucine, L-leucine, L-lysine, and L-phenylalanine had no significant effect. In contrast with the induction of GST Yp, the expression of the GST isoforms Ya and Yb was not changed by amino acid restriction. In conclusion, hepatic GST Yp gene expression is upregulated by a limited availability of sulfur amino acids.

Background The DEP domain is a globular domain containing approximately 90 amino acids, which was first discovered in 3 proteins: Drosophila disheveled, Caenorhabditis elegans EGL-10, and mammalian Pleckstrin; hence the term, DEP. DEPDC1B is categorized as a potential Rho GTPase-activating protein. The function of the DEP domain in signal transduction pathways is not fully understood. The DEPDC1B protein exhibits the characteristic features of a signaling protein, and contains 2 conserved domains (DEP and RhoGAP) that are involved in Rho GTPase signaling. Small GTPases, such as Rac, CDC42, and Rho, regulate a multitude of cell events, including cell motility, growth, differentiation, cytoskeletal reorganization and cell cycle progression. Results In this study, we found that it was a guanine nucleotide exchange factor and induced both cell migration in a cultured embryonic fibroblast cell line and cell invasion in cancer cell lines; moreover, it was observed to promote anchorage-independent growth in oral cancer cells. We also demonstrated that DEPDC1B plays a role in regulating Rac1 translocated onto cell membranes, suggesting that DEPDC1B exerts a biological function by regulating Rac1. We examined oral cancer tissue; 6 out of 7 oral cancer tissue test samples overexpressed DEPDC1B proteins, compared with normal adjacent tissue. Conclusions DEPDC1B was a guanine nucleotide exchange factor and induced both cell migration in a cultured embryonic fibroblast cell line and cell invasion in cancer cell lines; moreover, it was observed to promote anchorage-independent growth in oral cancer cells. We also demonstrated that DEPDC1B exerts a biological function by regulating Rac1. We found that oral cancer samples overexpressed DEPDC1B proteins, compared with normal adjacent tissue. Suggest that DEPDC1B plays a role in the development of oral cancer. We revealed that proliferation was linked to a novel DEPDC1B-Rac1-ERK1/2 signaling axis in oral cancer cell lines.

The individual and combined effects of dietary fat and garlic oil on two drug-metabolizing enzymes, cytochrome P 450 2B1 and the placental form of glutathione (GSH) S-transferase (PGST), in rat liver were examined in this study. Rats were fed a low corn oil, high corn oil or high fish oil diet and received various amount of garlic oil (0, 30, 80, 200 mg/kg body) orally three times per week for 6 wk. The fat energy in the low and high fat diets accounted for 11.6 and 45.7% of total energy, respectively. Final body weights did not differ among the three dietary fat groups and were not affected by garlic oil treatment. The fatty acid profile in hepatic phospholipids revealed higher eicosapentaenoic acid [20:5(n-3)] and docosahexaenoic acid [22:6(n-3)] levels in the fish oil-fed group than in the low and high corn oil-fed groups (P < 0.05). In contrast, the corn oil-fed groups had greater hepatic phospholipid arachidonic acid [20:4(n-6)] levels (P < 0.05). Both dietary fat and garlic oil significantly affected hepatic cytochrome 7-pentoxyresorufin O-dealkylase (PROD) activity and GST activity toward ethacrynic acid. Rats fed the high fish oil diet had 85 and 51 % higher PROD activity compared with those fed the low or the high corn oil diet, respectively (P < 0.05). The GST activity in the high fish oil and the high corn oil groups was 33 and 18% higher than that in the low corn oil group (P < 0.05), respectively, and the GST activity in rats fed the high fish oil diet was higher than in those fed the high corn oil diet (P < 0.05). Garlic oil dose-dependently increased GST activity. No interaction between dietary fat and garlic oil on PROD or GST activity was noted. Northern and Western blot analysis revealed that dietary fish oil increased both cytochrome P 450 2B1 and PGST mRNA and protein levels. Cytochrome P 450 2B1 and PGST mRNA and protein levels were also dose-dependently increased by garlic oil treatment. The effects of garlic oil and dietary fat on P 450 2B1 and PGST mRNA and protein expression were independent. These results indicate that dietary fat and garlic oil independently modulate P 450 2B1 and PGST expression at transcriptional and/or post-transcriptional stages.

Several specific cell cycle activities are dependent on cell-substratum adhesion in nontransformed cells, and the ability of the Ras oncoprotein to induce anchorage-independent growth is linked to its ability to abrogate this adhesion requirement. Ras signals via multiple downstream effector proteins, a synergistic combination of which may be required for the highly altered phenotype of fully transformed cells. We describe here studies on cell cycle regulation of anchorage-independent growth that utilize Ras effector loop mutants in NIH 3T3 and Rat 6 cells. Stable expression of activated H-Ras (12V) induced soft agar colony formation by both cell types, but each of three effector loop mutants (12V,35S, 12V,37G, and 12V,40C) was defective in producing this response. Expression of all three possible pairwise combinations of these mutants synergized to induce anchorage-independent growth of NIH 3T3 cells, but only the 12V,35S-12V,37G and 12V,37G-12V,40C combinations were complementary in Rat 6 cells. Each individual effector loop mutant partially relieved adhesion dependence of pRB phosphorylation, cyclin E-dependent kinase activity, and expression of cyclin A in NIH 3T3, but not Rat 6, cells. The pairwise combinations of effector loop mutants that were synergistic in producing anchorage-independent growth in Rat 6 cells also led to synergistic abrogation of the adhesion requirement for these cell cycle activities. The relationship between complementation in producing anchorage-independent growth and enhancement of cell cycle activities was not as clear in NIH 3T3 cells that expressed pairs of mutants, implying the existence of either thresholds for these activities or additional requirements in the induction of anchorage-independent growth. Ectopic expression of cyclin D1, E, or A synergized with individual effector loop mutants to induce soft agar colony formation in NIH 3T3 cells, cyclin A being particularly effective. Taken together, these data indicate that Ras utilizes multiple pathways to signal to the cell cycle machinery and that these pathways synergize to supplant the adhesion requirements of specific cell cycle events, leading to anchorage-independent growth.

Anchorage-independent growth is characteristic of neoplastic cells, but the signal transduction pathways that mediate this phenotype are poorly understood. Several important cell cycle events are dependent on cell-substratum adhesion in non-transformed cells, including activation of G1 cyclin-dependent kinases and expression of cyclin A; the adhesion requirement of these events is abrogated in Ras-transformed cells. The ER-1-2 mutant rat fibroblast cell line is: 1) resistant to Ras-mediated, anchorage-independent growth; 2) defective in Ras-mediated, adhesion-independent expression of cyclin A, but not adhesion-independent activation of cyclin-dependent kinases; and 3) rescued for Ras-induced, anchorage-independent growth by ectopic expression of cyclin A. We report here that extracellular ATP induces adhesion-independent expression of cyclin A and rescues growth in soft agar by ER-1-2 cells that express Ras. ADP, AMP and the non-hydrolyzable analog adenosine 5'-(beta, gamma-iminodiphosphate) are also effective, but adenosine is not. Adenine nucleotide-induced growth in soft agar is inhibited by reactive blue 2, an antagonist of some P2 purinoceptors. ATP does not induce adhesion-independent expression of cyclin A in ER-1-2 or control rat fibroblasts that do not express Ras, indicating a requirement for additional Ras-regulated signals for expression of this gene; one such signal may lead to phosphorylation of the retinoblastoma protein, pRB, and related proteins. These results suggest that extracellular ATP could play a role in the multistage carcinogenic process in vivo.

Novel mixed-lineage kinase protein zipper sterile-alpha-motif kinase (ZAK) was first cloned by our laboratory. Lung cancer is the leading cause of cancer-related death in the world, including in Taiwan. Here, we wanted to investigate whether ZAK plays a potential role in lung cancer development. First, Western blot analysis results demonstrated that four cell lines expressed high levels of ZAK from among a panel of 10 lung cancer cell lines, and two of three normal lung cells expressed ZAK. ZAK gene expressions were down-regulated in lung cancers by real-time PCR analysis. Overexpression of ZAK suppressed cell proliferation in parallel with increased phosphorylated levels of extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK). In contrast, ZAK silencing cells inhibited the expressions of phosphorylated ERK and JNK without affecting the expression of phosphorylated p38. The effect of the decreased cell growth rate was significantly but incompletely reversed when ZAK-overexpressing cells were treated with a specific ERK or JNK inhibitor. Moreover, c-Fos and c-Jun, the major downstream components of MAPKs, were up-regulated by ERK and JNK, respectively. When ZAK-overexpressing cells introduced with c-Jun RNA interference (RNAi), the activator protein-1 (AP-1) transcription activity detected by a secreted alkaline phosphatase (SEAP) assay was suppressed and the decreased cell number was reversed compared with the control RNAi-treated group. More importantly, ZAK significantly depressed tumor growth in in vivo study. Taken together, results from both in vitro and in vivo studies indicated that the decrease of lung cancer cell proliferation by ZAK may involve the ERK and JNK pathways via an AP-1 transcription factor.

We found that overexpression of RhoGDIβ, a Rho GDP dissociation inhibitor, induced hypertrophic growth and suppressed cell cycle progression in a cultured cardiomyoblast cell line. Knockdown of RhoGDIβ expression by RNA interference blocked hypertrophic growth. We further demonstrated that RhoGDIβ physically interacts with ZAK and is phosphorylated by ZAK in vitro, and this phosphorylation negatively regulates RhoGDIβ functions. Moreover, the ZAK-RhoGDIβ interaction may maintain ZAK in an inactive hypophosphorylated form. These two proteins could negatively regulate one another such that ZAK suppresses RhoGDIβ functions through phosphorylation and RhoGDIβ counteracts the effects of ZAK by physical interaction. Knockdown of ZAK expression in ZAK- and RhoGDIβ-expressing cells by ZAK-specific RNA interference restored the full functions of RhoGDIβ.

It is unclear whether cardiac hypertrophy and hypertrophy-related pathways will be induced by long-term intermittent hypoxia. Thirty-six Sprague-Dawley rats were randomly assigned into three groups: normoxia, and long-term intermittent hypoxia (12% O(2), 8 h per day) for 4 weeks (4WLTIH) or for 8 weeks (8WLTIH). Myocardial morphology, trophic factors and signalling pathways in the three groups were determined by heart weight index, histological analysis, Western blotting and reverse transcriptase-polymerase chain reaction from the excised left ventricle. The ratio of whole heart weight to body weight, the ratio of left ventricular weight to body weight, the gross vertical cross-section of the heart and myocardial morphological changes were increased in the 4WLTIH group and were further augmented in the 8WLTIH group. In the 4WLTIH group, tumour necrosis factor-alpha(TNFalpha), insulin-like growth factor (IGF)-II, phosphorylated p38 mitogen-activated protein kinase (P38), signal transducers and activators of transcription (STAT)-1 and STAT-3 were significantly increased in the cardiac tissues. However, in the 8WLTIH group, in addition to the above factors, interleukin-6, mitogen-activated protein kinase (MEK)5 and extracellular signal-regulated kinase (ERK)5 were significantly increased compared with the normoxia group. We conclude that cardiac hypertrophy associated with TNFalpha and IGF-II was induced by intermittent hypoxia. The longer duration of intermittent hypoxia further activated the eccentric hypertrophy-related pathway, as well as the interleukin 6-related MEK5-ERK5 and STAT-3 pathways, which could result in the development of cardiac dilatation and pathology.

This present study was designed to investigate the combined modulatory effect of garlic oil (GO) and fish oil (FO) on the antioxidant and drug metabolism systems. Rats were fed either a low-maize oil (MO) diet (50 g MO/kg), high-MO diet (235 g MO/kg) or high-FO diet (205 g FO+30 g MO/kg) and received different doses of GO (0–200 mg/kg body weight) three times per week for 6 weeks. Fatty acid analysis showed that 20: 5n−3 and 22: 6n−3 were incorporated into serum lipid at the expense of 18: 2n−6 and 20: 4n−6 in rats fed the high-FO diet. GO dose-dependently increased hepatic glutathioneS-transferase (GST), glutathione reductase, superoxide dismutase (SOD) and ethoxyresorufinO-deethylase (EROD) activities, but decreased glutathione peroxidase andN-nitrosodimethylamine demethylase (NDMAD) activities (PP

The cytotoxic and mutagenic effects of epoxy resin-based root canal sealer AH26 and AH-Plus were determined in vitro. Root canal sealers were eluted for 24 h in dimethyl sulfoxide (DMSO) and diluted in culture medium. Cytotoxic effects were assessed using the MTT [tetrazolium dye, 3-(4.5-dimethylthiazol-2-yl)-2.5-diphenyltetrazolium bromide, C18H16N5SBr] assay for mitochondrial enzyme activity and also the cell viability. Genotoxicity assays were assessed using the alkaline single cell gel electrophoresis assay (comet assay) for DNA damage measurement. Result indicated that both the AH26 and AH-Plus sealers exhibited a dose-dependent increase in astrocyte toxic effects. Additionally, dose-dependent astrocyte DNA damage was also noted for both sealers. Therefore, these epoxy resin-based sealers, AH26 and AH-Plus demonstrated both cytotoxicity and genotoxicity in vitro.

RhoGDIβ, a Rho GDP dissociation inhibitor, induced hypertrophic growth and cell migration in a cultured cardiomyoblast cell line, H9c2. We demonstrated that RhoGDIβ plays a previously undefined role in regulating Rac1 expression through transcription to induce hypertrophic growth and cell migration and that these functions are blocked by the expression of a dominant-negative form of Rac1. We also demonstrated that knockdown of RhoGDIβ expression by RNA interference blocked RhoGDIβ-induced Rac1 expression and cell migration. We demonstrated that the co-expression of ZAK and RhoGDIβ in cells resulted in an inhibition in the activity of ZAK to induce ANF expression. Knockdown of ZAK expression in ZAK-RhoGDIβ-expressing cells by ZAK-specific RNA interference restored the activities of RhoGDIβ.