81. Emodin Inhibits the Epithelial to Mesenchymal Transition of Epithelial Ovarian Cancer Cells via ILK/GSK-3β/Slug Signaling Pathway.
作者: Jingjing Lu.;Ying Xu.;Xuan Wei.;Zhe Zhao.;Jing Xue.;Peishu Liu.
来源: Biomed Res Int. 2016年2016卷6253280页
Epithelial ovarian cancer (EOC) is the most lethal gynecologic malignancy. Despite the anticancer capabilities of emodin observed in many cancers, including EOC, the underlying molecular mechanism remains to be elucidated. A crucial link has been discovered between the acquisition of metastatic traits and the epithelial-mesenchymal transition (EMT). The present study aimed to determine whether emodin could inhibit the EMT of EOC cells and explore the underlying mechanism. The CCK-8 assay and transwell assay showed that emodin effectively repressed the abilities of proliferation, invasion, and migration in A2780 and SK-OV-3 cells. The Western blot showed that emodin upregulated epithelial markers (E-cadherin and Claudin) while it downregulated mesenchymal markers (N-cadherin and Vimentin) and transcription factor (Slug) in a dose-dependent fashion. After transfection of siRNA-Slug, both Slug and N-cadherin were downregulated in EOC cells while E-cadherin was upregulated, which was intensified by emodin. Besides, emodin decreased the expression of ILK, p-GSK-3β, β-catenin, and Slug. Transfection of siRNA-ILK also achieved the same effects, which was further strengthened by following emodin treatment. Nevertheless, SB216763, an inhibitor of GSK-3β, could reverse the effects of emodin except for ILK expression. These findings suggest that emodin inhibited the EMT of EOC cells via ILK/GSK-3β/Slug signaling pathway.
82. Inhibitor of Nicotinamide Phosphoribosyltransferase Sensitizes Glioblastoma Cells to Temozolomide via Activating ROS/JNK Signaling Pathway.
作者: Jun Feng.;Peng-Fei Yan.;Hong-Yang Zhao.;Fang-Cheng Zhang.;Wo-Hua Zhao.;Min Feng.
来源: Biomed Res Int. 2016年2016卷1450843页
Overcoming temozolomide (TMZ) resistance is a great challenge in glioblastoma (GBM) treatment. Nicotinamide phosphoribosyltransferase (NAMPT) is a rate-limiting enzyme in the biosynthesis of nicotinamide adenine dinucleotide and has a crucial role in cancer cell metabolism. In this study, we investigated whether FK866 and CHS828, two specific NAMPT inhibitors, could sensitize GBM cells to TMZ. Low doses of FK866 and CHS828 (5 nM and 10 nM, resp.) alone did not significantly decrease cell viability in U251-MG and T98 GBM cells. However, they significantly increased the antitumor action of TMZ in these cells. In U251-MG cells, administration of NAMPT inhibitors increased the TMZ (100 μM)-induced apoptosis and LDH release from GBM cells. NAMPT inhibitors remarkably enhanced the activities of caspase-1, caspase-3, and caspase-9. Moreover, NAMPT inhibitors increased reactive oxygen species (ROS) production and superoxide anion level but reduced the SOD activity and total antioxidative capacity in GBM cells. Treatment of NAMPT inhibitors increased phosphorylation of c-Jun and JNK. Administration of JNK inhibitor SP600125 or ROS scavenger tocopherol with TMZ and NAMPT inhibitors substantially attenuated the sensitization of NAMPT inhibitor on TMZ antitumor action. Our data indicate a potential value of NAMPT inhibitors in combined use with TMZ for GBM treatment.
83. Hydrogen Sulfide Promotes Learning and Memory and Suppresses Proinflammatory Cytokines in Repetitive Febrile Seizures.
作者: Fei Zhuang.;Xuhong Zhou.;Hong Li.;Xiaochun Yang.;Zewu Dong.;Wendi Zhou.;Jian Chen.
来源: Neuroimmunomodulation. 2016年23卷5-6期271-277页
Hydrogen sulfide (H2S), as a novel gasotransmitter, plays important roles in a number of physiological and pathological processes. Its effectiveness has been demonstrated in different types of brain disorders but not in repetitive febrile seizure (febrile status epilepticus; FSE) models. This study aims to test whether a donor of H2S sodium sulfhydrate (NaHS) is also effective for FSE in rats.
84. Upregulation of CCL3/MIP-1alpha regulated by MAPKs and NF-kappaB mediates microglial inflammatory response in LPS-induced brain injury.
作者: Xiaobo Zhu.;Dee Wei.;Ou Chen.;Zhaohua Zhang.;Jiang Xue.;Shanying Huang.;Weiwei Zhu.;Yibiao Wang.
来源: Acta Neurobiol Exp (Wars). 2016年76卷4期304-317页
Growing evidence suggests that macrophage inflammatory protein (MIP)-1alpha (synonym CCL3) is upregulated in the neuroinflammatory processes initiated by some brain disorders, but its precise role and regulatory mechanism remain unclear. The present work aims to evaluate the role of CCL3/MIP-1alpha in lipopolysaccharide (LPS)-induced brain injury, and investigate whether the MAPKs and NF-kappaB regulate CCL3/MIP-1alpha expression. We firstly examined the patterns of CCL3/MIP-1alpha expression and phosphorylation of MAPKs in the brains of rats 6, 24, and 72 h after LPS administration. Additionally, LPS-treated rats were administered an anti-MIP-1alpha neutralizing antibody, and the microglial reaction and the expression of both cyclooxygenase-2 and inducible nitric oxide synthase (iNOS) were analyzed. We finally evaluated the effect of an inhibitor of P38 MAPK, an inhibitor of ERK1/2, or an inhibitor of NF-kappaB, on the levels of CCL3/MIP-1alpha protein and numbers of microglia in the brain. In the observation period, LPS induced CCL3/MIP-1alpha expression, which localized to OX-42-labeled microglia, leading to time-dependent increases in the phosphorylation of P38 MAPK and ERK1/2. The expression pattern of induced CCL3/MIP-1alpha was partly consistent with the phosphorylation of MAPKs (P38 MAPK, ERK1/2). Anti-MIP-1alpha attenuated microglial accumulation and the upregulation of cyclooxygenase-2 and iNOS. The inhibition of P38 MAPK, ERK1/2, or NF-kappaB signaling reduced the induced upregulation of CCL3/MIP-1alpha and the microglial accumulation. Our data suggest that upregulated CCL3/MIP-1alpha mediates the accumulation of microglia and the neuroinflammatory reaction, and its expression may be regulated by MAPKs and NF-kappaB in LPS-induced brain injury.
85. Neurosteroids Involvement in the Epigenetic Control of Memory Formation and Storage.
Memory is our ability to store and remember past experiences; it is the result of changes in neuronal circuits of specific brain areas as the hippocampus. During memory formation, neurons integrate their functions and increase the strength of their connections, so that synaptic plasticity is improved and consolidated. All these processes recruit several proteins at the synapses, whose expression is highly regulated by DNA methylation and histone tails posttranslational modifications. Steroids are known to influence memory process, and, among them, neurosteroids are implicated in neurodegenerative disease related to memory loss and cognitive impairment. The epigenetic control of neurosteroids involvement in memory formation and maintenance could represent the basis for neuroregenerative therapies.
86. Neurodegeneration and Glial Response after Acute Striatal Stroke: Histological Basis for Neuroprotective Studies.
作者: Rafael R Lima.;Luana N S Santana.;Rafael M Fernandes.;Elder M Nascimento.;Ana Carolina A Oliveira.;Luanna M P Fernandes.;Enio Mauricio N Dos Santos.;Patrycy Assis N Tavares.;Ijair Rogério Dos Santos.;Adriano Gimarães-Santos.;Walace Gomes-Leal.
来源: Oxid Med Cell Longev. 2016年2016卷3173564页
Stroke is a leading cause of death and neurological disability worldwide and striatal ischemic stroke is frequent in humans due to obstruction of middle cerebral artery. Several pathological events underlie damage progression and a comprehensive description of the pathological features following experimental stroke in both acute and chronic survival times is a necessary step for further functional studies. Here, we explored the patterns of microglial activation, astrocytosis, oligodendrocyte damage, myelin impairment, and Nogo-A immunoreactivity between 3 and 30 postlesion days (PLDs) after experimental striatal stroke in adult rats induced by microinjections of endothelin-1 (ET-1). The focal ischemia induced tissue loss concomitant with intense microglia activation between 3 and 14 PLDs (maximum at 7 PLDs), decreasing afterward. Astrocytosis was maximum around 7 PLDs. Oligodendrocyte damage and Nogo-A upregulation were higher at 3 PLDs. Myelin impairment was maximum between 7 and 14 PLDs. Nogo-A expression was higher in the first week in comparison to control. The results add important histopathological features of ET-1 induced stroke in subacute and chronic survival times. In addition, the establishment of the temporal evolution of these neuropathological events is an important step for future studies seeking suitable neuroprotective drugs targeting neuroinflammation and white matter damage.
87. Cisplatin Induces Apoptosis Through the Endoplasmic Reticulum-mediated, Calpain 1 Pathway in Triple-negative Breast Cancer Cells.
作者: Shadia M Al-Bahlani.;Khadija H Al-Bulushi.;Zaina M Al-Alawi.;Nadia Y Al-Abri.;Zuweina R Al-Hadidi.;Shaikha S Al-Rawahi.
来源: Clin Breast Cancer. 2017年17卷3期e103-e112页
Breast cancer is the most common cancer in women worldwide. Triple-negative breast cancer (TNBC) is an aggressive type that can be treated using platinum-based chemotherapy such as cisplatin (cis-diamminedichloroplatinum II). Although the calpain protein is essential in many cellular processes, including apoptosis, cell signaling, and proliferation, its role in cisplatin-induced apoptosis in TNBC cells is not fully understood. The present study assessed calpain 1-dependent, cisplatin-induced apoptosis in TNBC cells.
88. Protective effect of sugar cane extract against dextran sulfate sodium-induced colonic inflammation in mice.
Sugar cane extract (SCE) exhibits various biological effects and has been reported to enhance animal growth performance. However, the effect of SCE on inflammation in animals is still obscure. To study the effects and underlying mechanism of SCE on dextran sulfate sodium (DSS)-induced colonic inflammation, forty female ICR mice (26.63±0.19g, 6-week-old) were assigned into four groups: a control group (Cont), a DSS-challenged group (DSS), a SCE-supplemented group (SCE), and a DSS+SCE group (DSS+SCE). Mice in Cont group and DSS group were fed basic diet and other mice received 1% SCE supplemented in basic diet from 6-week to 8-week-old. Mice in DSS and DSS+SCE groups were also given a 4% DSS solution from 7-week to 8-week-old via drinking water to induce colonic inflammation. After 2 weeks, mice were sacrificed and samples were collected. The results showed that dietary SCE alleviated DSS induced growth suppression, splenic damage, colonic histological changes, colonic inflammation, oxidative stress, and colonic dysfunction of tight junctions. Meanwhile, the DSS exposure activated nuclear transcription factor kappa B p65 and inhibited nuclear factor E2-related factor 2 (Nrf2), while SCE markedly attenuated the DSS-promoted effect on the p65 nuclear accumulation and the DSS-inhibited effect on the Nrf2 nuclear accumulation. In conclusion, SCE conferred a protective role in the DSS-induced inflammation and the mechanism might be associated with the activated signals of the nuclear factor kappa B p65 and Nrf2.
89. BCFA suppresses LPS induced IL-8 mRNA expression in human intestinal epithelial cells.
作者: Y Yan.;Z Wang.;J Greenwald.;K S D Kothapalli.;H G Park.;R Liu.;E Mendralla.;P Lawrence.;X Wang.;J T Brenna.
来源: Prostaglandins Leukot Essent Fatty Acids. 2017年116卷27-31页
Branched chain fatty acids (BCFA) are components of common food fats and are major constituents of the normal term human newborn GI tract. Polyunsaturated fatty acids (PUFA) have been suggested to reduce the risk and development of inflammatory bowel diseases (IBD); however, little is known about the influence of BCFA on inflammation. We investigated the effect of BCFA on interleukin (IL)-8 and NF-κB production in a human intestinal epithelial cell line (Caco-2). Cells were pre-treated with specific BCFA, or DHA, or EPA, and then activated with lipopolysaccharide (LPS). Both anteiso- and iso- BCFA reduce IL-8. Anteiso-BCFA more effectively suppressed IL-8 than iso-BCFA in LPS stimulated Caco-2 cells. However BCFA in general were less effective than DHA or EPA. Activated BCFA-treated cells expressed less of the cell surface Toll-like receptor 4 (TLR-4) compared to controls. These are the first data to show the reduction of pro-inflammatory markers in human cells mediated by BCFA.
90. Effects of treatment with sucrose in drinking water on liver histology, lipogenesis and lipogenic gene expression in rats fed high-fiber diet.
作者: Tomislav Mašek.;Natalija Filipović.;Ana Vuica.;Kristina Starčević.
来源: Prostaglandins Leukot Essent Fatty Acids. 2017年116卷1-8页
We studied the influence of sucrose in drinking water on liver histology, fatty acid profile and lipogenic genes expression in rats maintained on high-fiber. The experimental groups were: control group (water) and sucrose group (sucrose solution in drinking water, 30% w/v). Liver histology of sucrose treated rats revealed steatosis and increased number of αSMA immunoreactive cells without the signs of fibrosis. Sucrose treatment increased de novo lipogenesis, lipid peroxidation and MUFA content and decreased PUFA content, C18:2n6 and C20:4n6 content in total phospholipids and phosphatidylethanolamine and C18:2n6 content in cardiolipin. RT-qPCR revealed increase in Δ-9-desaturase and SREBP1c gene expression and decrease in the Δ-5-desaturase and elongase 5 expression. Treatment with sucrose extensively changes fatty acid composition of hepatic lipid and phospholipid classes including cardiolipin, increases oxidative stress and causes pathological changes in liver in rats maintained on high-fiber diet.
91. [Tripotolide ameliorates inflammation and apoptosis induced by focal cerebral ischemia/reperfusion in rats].
作者: Shi Bai.;Yayi Sun.;Lijuan Wu.;Zhongmin Wu.;Marong Fang.
来源: Zhejiang Da Xue Xue Bao Yi Xue Ban. 2016年45卷5期493-500页
Objective: To investigate the effects of triptolide on inflammation and apoptosis induced by focal cerebral ischemia/reperfusion in rats. Methods: The rat model of focal cerebral ischemia/reperfusion injury was established according to Longa's method. A total of 80 SD rats were randomly divided into 5 groups:normal control, sham group, DMSO group, middle cerebral artery occlusion (MCAO) group, and MCAO with tripolide treatment group. TTC staining was used to examine the site and volume of cerebral infarction, and Longa score was employed for neurological disorders measurement. Number of astrocytes was measured by fluorescence staining, and neuronal apoptosis was determined by TUNEL staining. The expressions of inducible nitric oxide synthase(iNOS), cyclooxygenase 2(COX-2) and NF-κB proteins were detected by immunohistochemistry, and the expression of iNOS, COX-2 mRNA was detected by real-time PCR. Results: Compared with DMSO group and MCAO group, brain edema was improved (80.03±0.46)% (P<0.05), infarct volume was reduced (8.3±1.4)% (P<0.01), Longa score was decreased (1.38±0.20, P<0.05) in triptolide treatment group. Meanwhile triptolide also dramatically reduced the number of GFAP-positive astrocytes (P<0.05), alleviated protein expression of COX-2 (91.67±1.31), iNOS (95.24±5.07) and NF-κB (75.03±2.06) triggered by MCAO (all P<0.05), and induced a down-regulation of cell apoptosis as showed by TUNEL assay (64.15±3.52, P<0.05). Conclusion: Triptolide can reduce the cerebral infarction volume, attenuate brain edema and ameliorate the neurological deficits induced by cerebral ischemia-reperfusion injury rats, indicating that it might be used as a potential anti-inflammatory agent.
92. [Effect of methyleugenol on expression of MUC5AC in nasal mucosa of rats with allergic rhinitis].
作者: Nannan Meng.;Yun Hou.;Yan Gui.;Kehu Xi.;Youhu Wang.;Jing Yang.;Hong Chen.;Xiaobing Zhang.
来源: Zhejiang Da Xue Xue Bao Yi Xue Ban. 2016年45卷5期477-485页
Objective: To investigate the effect of methyleugenol on expression of MUC5AC in nasal mucosa of rats with allergic rhinitis (AR). Methods: Seventy-two Wistar rats were randomly divided into 6 groups:normal control group, AR group, loratadine group, low-dose methyleugenol group, middle-dose methyleugenol group and high-dose methyleugenol group with 12 rats in each group. AR was induced by intraperitoneal injection of ovalbumin in latter 5 groups. 10 mg loratadine q.d was given to rats in loratadine group by gavage; and 10 mg/kg, 20 mg/kg and 40 mg/kg methyleugenol were given by gavege q.d to rats in low-, middle-and high-dose methyleugenol groups, respectively. Nasal mucosa samples were obtained from rats at 1, 2, 4 and 6 weeks after drug intervention. The expression of MUC5AC protein and mRNA in nasal mucosa was detected by immunohistochemistry and real-time fluorescence quota PCR (RT-PCR), respectively. Results: Compared with AR, the percentage of cells staining positively for MUC5AC protein and the relative quantity of MUC5AC mRNA in middle-and high-dose methyleugenol groups were significantly decreased after 2 and 4 weeks of drug intervention (P<0.05), but no such decrease was observed in low-dose methyleugenol group at all time points (P>0.05). The percentage of cells with positive expression of MUC5AC protein and mRNA in loratadine group were significantly decreased after 1 week of administration (P<0.05). The percentage of cells with positive MUC5AC protein in middle-dose methyleugenol group was higher than that in loratadine group (P<0.05) after 6 week of drug intervention, but the difference was not seen in high-dose group (P>0.05). There was no significant difference in relative quantities of MUC5AC mRNA after 4 weeks of administration between high-and middle-dose methyeugenol groups and loratadine group (P>0.05). Conclusion: Methyleugenol can attenuate AR through inhibiting the expression of MUC5AC mRNA and protein in nasal mucosa of AR rats.
93. Parkin deficiency exacerbate ethanol-induced dopaminergic neurodegeneration by P38 pathway dependent inhibition of autophagy and mitochondrial function.
作者: Chul Ju Hwang.;Young Eun Kim.;Dong Ju Son.;Mi Hee Park.;Dong-Young Choi.;Pil-Hoon Park.;Mats Hellström.;Sang-Bae Han.;Ki-Wan Oh.;Eun Kyung Park.;Jin Tae Hong.
来源: Redox Biol. 2017年11卷456-468页
Parkinson's disease (PD) is a neurodegenerative disease characterized by selective degeneration of dopaminergic neurons in the substantia nigra. Parkin (which encoded by Park2), an E3 ubiquitin ligase, is the most frequently mutated gene that has casually been linked to autosomal recessive early onset familial PD. We tested the effect of Park2 on ethanol-induced dopaminergic neurodegeneration in Park2 knockout (KO) transgenic mice after chronic ethanol feeding. Male Park2 wild type (WT) and KO mice (8 weeks old) were fed on a Lieber-DeCarli diet containing 6.6% ethanol for 2 weeks, and compared their responses. We found that knockout of Park2 exacerbates ethanol-induced behavioral impairment as well as dopamine depletion. In the mechanism study, we found that knockout of Park2 increased reactive oxygen species (ROS) production, mitophagy formation, mitochondrial dysfunction, and expression of pro-apoptotic proteins, but decreased expression of pro-autophagic proteins. Knockout of Park2 also increased ethanol-induced activation of p38 mitogen-activated protein kinase. In addition, ROS production, mitophagy formation, mitochondrial dysfunction, and expression of pro-apoptotic proteins were increased, but expression of pro-autophagic proteins were decreased by a treatment of ethanol (100μM) in Park2 siRNA-transfacted PC12 cells (5μM). Moreover, the exacerbating effects of Park2 deletion on ethanol-induced ROS generation, mitophagy, mitochondrial dysfunction as well as cell death were reduced by p38 specific inhibitor (SB203580) in in vitro (10μM) and in vivo 10mg/kg). Park2 deficiency exacerbates ethanol-induced dopaminergic neuron damage through p38 kinase dependent inhibition of autophagy and mitochondrial function.
94. Hepatic transcriptional responses to copper in the three-spined stickleback are affected by their pollution exposure history.
作者: Tamsyn M Uren Webster.;Tim D Williams.;Ioanna Katsiadaki.;Anke Lange.;Ceri Lewis.;Janice A Shears.;Charles R Tyler.;Eduarda M Santos.
来源: Aquat Toxicol. 2017年184卷26-36页
Some fish populations inhabiting contaminated environments show evidence of increased chemical tolerance, however the mechanisms contributing to this tolerance, and whether this is heritable, are poorly understood. We investigated the responses of two populations of wild three-spined stickleback (Gasterosteus aculeatus) with different histories of contaminant exposure to an oestrogen and copper, two widespread aquatic pollutants. Male stickleback originating from two sites, the River Aire, with a history of complex pollution discharges, and Siblyback Lake, with a history of metal contamination, were depurated and then exposed to copper (46μg/L) and the synthetic oestrogen ethinyloestradiol (22ng/L). The hepatic transcriptomic response was compared between the two populations and to a reference population with no known history of exposure (Houghton Springs, Dorset). Gene responses included those typical for both copper and oestrogen, with no discernable difference in response to oestrogen between populations. There was, however, some difference in the magnitude of response to copper between populations. Siblyback fish showed an elevated baseline transcription of genes encoding metallothioneins and a lower level of metallothionein induction following copper exposure, compared to those from the River Aire. Similarly, a further experiment with an F1 generation of Siblyback fish bred in the laboratory found evidence for elevated transcription of genes encoding metallothioneins in unexposed fish, together with an altered transcriptional response to 125μg/L copper, compared with F1 fish originating from the clean reference population exposed to the same copper concentration. These data suggest that the stickleback from Siblyback Lake have a differential response to copper, which is inherited by the F1 generation in laboratory conditions, and for which the underlying mechanism may include an elevation of baseline transcription of genes encoding metallothioneins. The genetic and/or epigenetic mechanisms contributing to this inherited alteration of metallothionein transcription have yet to be established.
95. Protective Effects of Emodin-Induced Neutrophil Apoptosis via the Ca2+-Caspase 12 Pathway against SIRS in Rats with Severe Acute Pancreatitis.
作者: Gui-Jun Wang.;Yue Wang.;Yong-Sheng Teng.;Fa-Lv Sun.;Hong Xiang.;Jian-Jun Liu.;Shi-Lin Xia.;Gui-Xin Zhang.;Hai-Long Chen.;Dong Shang.
来源: Biomed Res Int. 2016年2016卷1736024页
Severe acute pancreatitis (SAP) results in high mortality. This is partly because of early multiple organ dysfunction syndromes that are usually caused by systemic inflammatory response syndrome (SIRS). Many studies have reported the beneficial effects of emodin against SAP with SIRS. However, the exact mechanism underlying the effect of emodin remains unclear. This study was designed to explore the protective effects and underlying mechanisms of emodin against SIRS in rats with SAP. In the present study, cytosolic Ca2+ levels, calpain 1 activity, and the expression levels of the active fragments of caspases 12 and 3 decreased in neutrophils from rats with SAP and increased after treatment with emodin. Delayed neutrophil apoptosis occurred in rats with SAP and emodin was able to reverse this delayed apoptosis and inhibit SIRS. The effect of emodin on calpain 1 activity, the expression levels of the active fragments of caspases 12 and 3, neutrophil apoptosis, and SIRS scores were attenuated by PD150606 (an inhibitor of calpain). These results suggest that emodin inhibits SIRS in rats with SAP by inducing circulating neutrophil apoptosis via the Ca2+-calpain 1-caspase 12-caspase 3 signaling pathway.
96. Gerosuppression by pan-mTOR inhibitors.
Rapamycin slows organismal aging and delays age-related diseases, extending lifespan in numerous species. In cells, rapamycin and other rapalogs such as everolimus suppress geroconversion from quiescence to senescence. Rapamycin inhibits some, but not all, activities of mTOR. Recently we and others demonstrated that pan-mTOR inhibitors, known also as dual mTORC1/C2 inhibitors, suppress senescent phenotype. As a continuation of these studies, here we investigated in detail a panel of pan-mTOR inhibitors, to determine their optimal gerosuppressive concentrations. During geroconversion, cells become hypertrophic and flat, accumulate lysosomes (SA-beta-Gal staining) and lipids (Oil Red staining) and lose their re-proliferative potential (RPP). We determined optimal gerosuppressive concentrations: Torin1 (30 nM), Torin 2 (30 nM), AZD8055 (100 nM), PP242 (300 nM), both KU-006379 and GSK1059615 (1000 nM). These agents decreased senescence-associated hypertrophy with IC50s: 20, 18, 15, 200 and 400 nM, respectively. Preservation of RPP by pan-mTOR inhibitors was associated with inhibition of the pS6K/pS6 axis. Inhibition of rapamycin-insensitive functions of mTOR further contributed to anti-hypertrophic and cytostatic effects. Torin 1 and PP242 were more "rapamycin-like" than Torin 2 and AZD8055. Pan-mTOR inhibitors were superior to rapamycin in suppressing hypertrophy, senescent morphology, Oil Red O staining and in increasing so-called "chronological life span (CLS)". We suggest that, at doses lower than anti-cancer concentrations, pan-mTOR inhibitors can be developed as anti-aging drugs.
97. From the Cover: Embryonic Exposure to TCDD Impacts Osteogenesis of the Axial Skeleton in Japanese medaka, Oryzias latipes.
作者: AtLee T D Watson.;Antonio Planchart.;Carolyn J Mattingly.;Christoph Winkler.;David M Reif.;Seth W Kullman.
来源: Toxicol Sci. 2017年155卷2期485-496页
Recent studies from mammalian, fish, and in vitro models have identified bone and cartilage development as sensitive targets for dioxins and other aryl hydrocarbon receptor ligands. In this study, we assess how embryonic 2,3,7,8-tetrachlorochlorodibenzo-p-dioxin (TCDD) exposure impacts axial osteogenesis in Japanese medaka (Oryzias latipes), a vertebrate model of human bone development. Embryos from inbred wild-type Orange-red Hd-dR and 3 transgenic medaka lines (twist:EGFP, osx/sp7:mCherry, col10a1:nlGFP) were exposed to 0.15 nM and 0.3 nM TCDD and reared until 20 dpf. Individuals were stained for mineralized bone and imaged using confocal microscopy to assess skeletal alterations in medial vertebrae in combination with a qualitative spatial analysis of osteoblast and osteoblast progenitor cell populations. Exposure to TCDD resulted in an overall attenuation of vertebral ossification characterized by truncated centra, and reduced neural and hemal arch lengths. Effects on mineralization were consistent with modifications in cell number and cell localization of transgene-labeled osteoblast and osteoblast progenitor cells. Endogenous expression of osteogenic regulators runt-related transcription factor 2 (runx2) and osterix (osx/sp7), and extracellular matrix genes osteopontin (spp1), collagen type I alpha I (col1), collagen type X alpha I (col10a1), and osteocalcin (bglap/osc) was significantly diminished at 20 dpf following TCDD exposure as compared with controls. Through global transcriptomic analysis more than 590 differentially expressed genes were identified and mapped to select pathological states including inflammatory disease, connective tissue disorders, and skeletal and muscular disorders. Taken together, results from this study suggest that TCDD exposure inhibits axial bone formation through dysregulation of osteoblast differentiation. This approach highlights the advantages and sensitivity of using small fish models to investigate how xenobiotic exposure may impact skeletal development.
98. Redeploying β-Lactam Antibiotics as a Novel Antivirulence Strategy for the Treatment of Methicillin-Resistant Staphylococcus aureus Infections.
作者: Elaine M Waters.;Justine K Rudkin.;Simone Coughlan.;Geremy C Clair.;Joshua N Adkins.;Suzanna Gore.;Guoqing Xia.;Nikki S Black.;Tim Downing.;Eoghan O'Neill.;Aras Kadioglu.;James P O'Gara.
来源: J Infect Dis. 2017年215卷1期80-87页
Innovative approaches to the use of existing antibiotics is an important strategy in efforts to address the escalating antimicrobial resistance crisis. We report a new approach to the treatment of methicillin-resistant Staphylococcus aureus (MRSA) infections by demonstrating that oxacillin can be used to significantly attenuate the virulence of MRSA despite the pathogen being resistant to this drug. Using mechanistic in vitro assays and in vivo models of invasive pneumonia and sepsis, we show that oxacillin-treated MRSA strains are significantly attenuated in virulence. This effect is based primarily on the oxacillin-dependent repression of the accessory gene regulator quorum-sensing system and altered cell wall architecture, which in turn lead to increased susceptibility to host killing of MRSA. Our data indicate that β-lactam antibiotics should be included in the treatment regimen as an adjunct antivirulence therapy for patients with MRSA infections. This would represent an important change to current clinical practice for treatment of MRSA infection, with the potential to significantly improve patient outcomes in a safe, cost-effective manner.
99. Gamma-Glutamylcysteine Ethyl Ester Protects against Cyclophosphamide-Induced Liver Injury and Hematologic Alterations via Upregulation of PPARγ and Attenuation of Oxidative Stress, Inflammation, and Apoptosis.
Gamma-glutamylcysteine ethyl ester (GCEE) is a precursor of glutathione (GSH) with promising hepatoprotective effects. This investigation aimed to evaluate the hepatoprotective effects of GCEE against cyclophosphamide- (CP-) induced toxicity, pointing to the possible role of peroxisome proliferator activated receptor gamma (PPARγ). Wistar rats were given GCEE two weeks prior to CP. Five days after CP administration, animals were sacrificed and samples were collected. Pretreatment with GCEE significantly alleviated CP-induced liver injury by reducing serum aminotransferases, increasing albumin, and preventing histopathological and hematological alterations. GCEE suppressed lipid peroxidation and nitric oxide production and restored GSH and enzymatic antioxidants in the liver, which were associated with downregulation of COX-2, iNOS, and NF-κB. In addition, CP administration significantly increased serum proinflammatory cytokines and the expression of liver caspase-3 and BAX, an effect that was reversed by GCEE. CP-induced rats showed significant downregulation of PPARγ which was markedly upregulated by GCEE treatment. These data demonstrated that pretreatment with GCEE protected against CP-induced hepatotoxicity, possibly by activating PPARγ, preventing GSH depletion, and attenuating oxidative stress, inflammation, and apoptosis. Our findings point to the role of PPARγ and suggest that GCEE might be a promising agent for the prevention of CP-induced liver injury.
100. New oxylipins produced at the end of a diatom bloom and their effects on copepod reproductive success and gene expression levels.
作者: Chiara Lauritano.;Giovanna Romano.;Vittoria Roncalli.;Angela Amoresano.;Carolina Fontanarosa.;Mauro Bastianini.;Federica Braga.;Ylenia Carotenuto.;Adrianna Ianora.
来源: Harmful Algae. 2016年55卷221-229页
Diatoms are dominant photosynthetic organisms in the world's oceans and are considered essential in the transfer of energy to higher trophic levels. However, these unicellular organisms produce secondary metabolites deriving from the oxidation of fatty acids, collectively termed oxylipins, with negative effects on predators, such as copepods, that feed on them (e.g. reduction in survival, egg production and hatching success) and, indirectly, on higher trophic levels. Here, a multidisciplinary study (oxylipin measurements, copepod fitness, gene expression analyses, chlorophyll distribution, phytoplankton composition, physico-chemical characteristics) was carried out at the end of the spring diatom bloom in April 2011 in the Northern Adriatic Sea (Mediterranean Sea) in order to deeply investigate copepod-diatom interactions, chemical communication and response pathways. The results show that the transect with the lowest phytoplankton abundance had the lowest copepod egg production and hatching success, but the highest oxylipin concentrations. In addition, copepods in both the analyzed transects showed increased expression levels of key stress-related genes (e.g. heat-shock proteins, catalase, glutathione S-transferase, aldehyde dehydrogenase) compared to control laboratory conditions where copepods were fed with the dinoflagellate Prorocentrum minimum which does not produce any oxylipins. New oxylipins that have never been reported before for microalgae are described for the first time, giving new insights into the complex nature of plant-animal signaling and communication pathways at sea. This is also the first study providing insights on the copepod response during a diatom bloom at the molecular level.
|