261. Induction of G2/M phase arrest and apoptosis by a new tetrahydroingenol diterpenoid from Euphorbia erythradenia Bioss. in melanoma cancer cells.
作者: Faranak Fallahian.;Mustafa Ghanadian.;Mahmoud Aghaei.;Seyed Mohammad Zarei.
来源: Biomed Pharmacother. 2017年86卷334-342页
In the current study, a new tetrahydroingenol diterpene isolated from Euphorbia erythradenia, 7,13-diacetyl-5-angeloyl-20-nicotinyl-3-propionyl-1,2,6,7-tetrahydroingenol (DANPT), were tested for the molecular mechanism of its anti-cancer activity in two human melanoma cancer cell lines, A375 and HMCB. DANPT was found cytotoxic against A375 and HMCB cells with IC50 value of 15.37±2.6μM and 15.62±1.89μM, respectively. Flow cytometric analysis showed that DANPT halted the A375 and HMCB cells in G2/M phase and induced apoptosis in a dose-dependent manner. Cell cycle arrest was associated with down-regulation of cyclin B and Cdk-1 and subsequent up-regulation of p53 and p21. Moreover, DANPT induced Bax and inhibited Bcl-2 expression, which results in increasing Bax/Bcl-2 ratio and activation of caspase-3. Furthermore, the apoptotic effect of DANPT was also related to ROS production and loss of mitochondrial membrane potential (ΔYm). Overall, our results suggest that DANPT can inhibit proliferation of human melanoma cancer cells by promoting apoptosis and inducing cell cycle arrest and therefore, it can be a promising natural agent for the treatment of melanoma cancer.
262. Possible involvement of Nrf2 and PPARγ up-regulation in the protective effect of umbelliferone against cyclophosphamide-induced hepatotoxicity.
作者: Ayman M Mahmoud.;Mousa O Germoush.;Mohammed F Alotaibi.;Omnia E Hussein.
来源: Biomed Pharmacother. 2017年86卷297-306页
Umbelliferone (UMB) is a coumarin derivative with promising hepatoprotective effects. In this study, we examined the possible protective effects of UMB against cyclophosphamide (CP)-induced hepatotoxicity, addressing the question of the possible role of nuclear factor erythroid 2-related factor 2 (Nrf2) and peroxisome proliferator activated receptor gamma (PPARγ). Wistar rats were orally administered UMB at doses 50 and 100mg/kg two weeks prior to CP injection. Five days after CP administration, the rats were sacrificed and samples were collected for analyses. CP induced a significant increase in circulating liver marker enzymes and pro-inflammatory cytokines. Hepatic lipid peroxidation and nitric oxide levels, and nuclear factor-kappaB (NF-κB) and inducible nitric oxide synthase (iNOS) expression were significantly increased following CP administration. UMB supplementation attenuated CP-induced inflammation and oxidative stress as assessed by restoration of the activity and expression of the antioxidant defenses, and suppression of pro-inflammatory cytokines. Histological examination also showed that UMB could significantly reduce CP-induced alterations. CP-induced rats showed significant down-regulation of Nrf2, HO-1 and PPARγ, an effect that was markedly reversed by UMB. In conclusion, the hepatoprotective effects of UMB appear to depend on co-activation of PPARγ and Nrf2, and subsequent suppression of oxidative stress and inflammation.
263. Effects of peppermint tea consumption on the activities of CYP1A2, CYP2A6, Xanthine Oxidase, N-acetyltranferase-2 and UDP-glucuronosyltransferases-1A1/1A6 in healthy volunteers.
作者: Elias Begas.;Athanasia Tsioutsiouliti.;Evangelos Kouvaras.;Serkos A Haroutounian.;Konstantinos M Kasiotis.;Dimitrios Kouretas.;Eftihia Asprodini.
来源: Food Chem Toxicol. 2017年100卷80-89页
Peppermint leaves are widely used for the symptomatic treatment of digestive disorders. Previous studies have shown significant effects of its natural products on human enzyme activity; however, there is no study available concerning the effects of peppermint tea on metabolizing enzymes in humans. Aim of the present study was to investigate the effect of peppermint tea on CYP1A2, CYP2A6, Xanthine Oxidase (XO), N-acetyltranferase-2 (NAT2) and UDP-glucuronosyltransferases-1A1/1A6 (UGT1A1/1A6) activities in healthy subjects. Four males and five females consumed peppermint tea (2 g of dry leaves/200 mL water, twice daily) for six days. CYP1A2, CYP2A6, XO, NAT2 and UGT1A1/1A6 activities were determined before and at the end of the study period, using the following caffeine and paracetamol metabolic ratios: CYP1A2: 17MX/137MX (saliva) and (AFMU+1MU+1MX)/17MU (urine); CYP2A6: 17MU/(17MU + 17MX), XO: 1MU/(1MU+1MX), NAT2, AFMU/(AFMU+1MU+1MX) and UGT1A1/1A6 glucuronidated/total paracetamol, all determined in urine. NAT2 metabolic ratio was significantly reduced following peppermint consumption (0.15 ± 0.13 vs 0.14 ± 0.13; p < 0.05). CYP1A2 urine and saliva indices were reduced, yet not significantly, following peppermint consumption (urine: 3.17 ± 1.08 vs 2.91 ± 0.76, saliva: 0.56 ± 0.12 vs 0.50 ± 0.12; p > 0.05). Peppermint had no influence on CYP2A6, XO and UGT1A1/1A6 indices. Daily ingestion of peppermint tea may alter pharmacokinetics of clinically administered drugs and promote cancer chemoprevention through NAT2 inhibition.
264. Outside in: The matrix as a modifier of muscular dystrophy.
作者: Mattia Quattrocelli.;Melissa J Spencer.;Elizabeth M McNally.
来源: Biochim Biophys Acta Mol Cell Res. 2017年1864卷3期572-579页
Muscular dystrophies are genetic conditions leading to muscle degeneration and often, impaired regeneration. Duchenne Muscular Dystrophy is a prototypical form of muscular dystrophy, and like other forms of genetically inherited muscle diseases, pathological progression is variable. Variability in muscular dystrophy can arise from differences in the manner in which the primary mutation impacts the affected protein's function; however, clinical heterogeneity also derives from secondary mutations in other genes that can enhance or reduce pathogenic features of disease. These genes, called genetic modifiers, regulate the pathophysiological context of dystrophic degeneration and regeneration. Understanding the mechanistic links between genetic modifiers and dystrophic progression sheds light on pathologic remodeling, and provides novel avenues to therapeutically intervene to reduce muscle degeneration. Based on targeted genetic approaches and unbiased genomewide screens, several modifiers have been identified for muscular dystrophy, including extracellular agonists of signaling cascades. This review will focus on identification and possible mechanisms of recently identified modifiers for muscular dystrophy, including osteopontin, latent TGFβ binding protein 4 (LTBP4) and Jagged1. Moreover, we will review the investigational approaches that aim to target modifier pathways and thereby counteract dystrophic muscle wasting.
265. Estradiol regulates expression of miRNAs associated with myogenesis in rainbow trout.
作者: Prasanthi P Koganti.;Jian Wang.;Beth Cleveland.;Hao Ma.;Gregory M Weber.;Jianbo Yao.
来源: Mol Cell Endocrinol. 2017年443卷1-14页
17β-Estradiol (E2) is a steroid hormone that negatively affects muscle growth in rainbow trout, but the mechanism associated with this response is not fully understood. To better characterize the effects of E2 on muscle, we identified differentially regulated microRNAs (miRNAs) and muscle atrophy-related transcripts in juvenile rainbow trout exposed to E2. Small RNA-Seq analysis of E2-treated vs. control muscle identified 36 differentially expressed miRNAs including those known to be involved in myogenesis, cell cycle, apoptosis, and cell death. Some important myogenic miRNAs, such as miR-133 and miR-206, are upregulated while others like miR-145 and miR-499, are downregulated. Gene Ontology analysis of the target genes regulated by the miRNAs involved in atrophy and cell cycle indicates that E2 influence leads to expansion of quiescent myogenic precursor cell population to address atrophying mature muscle in rainbow trout during sexual development.
266. Lithium increases hippocampal SNARE protein abundance after traumatic brain injury.
Rodent models of traumatic brain injury (TBI) reproduce secondary injury sequela and cognitive impairments observed in patients afflicted by a TBI. Impaired neurotransmission has been reported in the weeks following experimental TBI, and may be a contributor to behavioral dysfunction. The soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) complex, the machinery facilitating vesicular docking and fusion, is a highly-conserved mechanism important for neurotransmission. Following TBI, there is a reduction in both the formation of the SNARE complex and the abundance of multiple SNARE proteins, including the chaperone protein cysteine string protein α (CSPα). Treatment with lithium in naïve rats reportedly increases the expression of CSPα. In the context of TBI, brain-injured rats treated with lithium exhibit improved outcome in published reports, but the mechanisms underlying the improvement are poorly understood. The current study evaluated the effect of lithium administration on the abundance of SNARE proteins and SNARE complex formation, hemispheric tissue loss, and neurobehavioral performance following controlled cortical impact (CCI). Sprague Dawley rats were subjected to CCI or sham injury, and treated daily with lithium chloride or vehicle for up to 14days. Administration of lithium after TBI modestly improved spatial memory at 14days post-injury. Semi-quantitative immunoblot analysis of hippocampal lysates revealed that treatment with lithium attenuated reductions in key SNARE proteins and SNARE complex formation at multiple time points post-injury. These findings highlight that treatment with lithium increased the abundance of synaptic proteins that facilitate neurotransmission and may contribute to improved cognitive function after TBI.
267. Pellino-1 promotes lung carcinogenesis via the stabilization of Slug and Snail through K63-mediated polyubiquitination.
作者: Yoon Kyung Jeon.;Chung Kwon Kim.;Kyung Rim Hwang.;Hye-Young Park.;Jaemoon Koh.;Doo Hyun Chung.;Chang-Woo Lee.;Geun-Hyoung Ha.
来源: Cell Death Differ. 2017年24卷3期469-480页
Pellino-1 is an E3 ubiquitin ligase acting as a critical mediator for a variety of immune receptor signaling pathways, including Toll-like receptors, interleukin-1 receptor and T-cell receptors. We recently showed that the Pellino-1-transgenic (Tg) mice developed multiple tumors with different subtypes in hematolymphoid and solid organs. However, the molecular mechanism underlying the oncogenic role of Pellino-1 in solid tumors remains unknown. Pellino-1-Tg mice developed adenocarcinoma in the lungs, and Pellino-1 expression was higher in human lung adenocarcinoma cell lines compared with non-neoplastic bronchial epithelial cell lines. Pellino-1 overexpression increased the cell proliferation, survival, colony formation, invasion and migration of lung adenocarcinoma cells, whereas Pellino-1 knock-down showed the opposite effect. Pellino-1 overexpression activated PI3K/Akt and ERK signaling pathways and elicited an epithelial-mesenchymal transition (EMT) phenotype of lung adenocarcinoma cells. Pellino-1-mediated EMT was demonstrated through morphology, the upregulation of Vimentin, Slug and Snail expression and the downregulation of E-cadherin and β-catenin expression. Notably, Pellino-1 had a direct effect on the overexpression of Snail and Slug through Lys63-mediated polyubiquitination and the subsequent stabilization of these proteins. Pellino-1 expression level was significantly correlated with Snail and Slug expression in human lung adenocarcinoma tissues, and lung tumors from Pellino-1-Tg mice showed Snail and Slug overexpression. The Pellino-1-mediated increase in the migration of lung adenocarcinoma cells was mediated by Snail and Slug expression. Taken together, these results show that Pellino-1 contributes to lung tumorigenesis by inducing overexpression of Snail and Slug and promoting EMT. Pellino-1 might be a potential therapeutic target for lung cancer.
268. Down-regulation of common NFκB-iNOS pathway by chronic Thalidomide treatment improves Hepatopulmonary Syndrome and Muscle Wasting in rats with Biliary Cirrhosis.
作者: Tzu-Hao Li.;Pei-Chang Lee.;Kuei-Chuan Lee.;Yun-Cheng Hsieh.;Chang-Youh Tsai.;Ying-Ying Yang.;Shiang-Fen Huang.;Tung-Hu Tsai.;Shie-Liang Hsieh.;Ming-Chih Hou.;Han-Chieh Lin.;Shou-Dong Lee.
来源: Sci Rep. 2016年6卷39405页
Thalidomide can modulate the TNFα-NFκB and iNOS pathway, which involve in the pathogenesis of hepatopulmonary syndrome (HPS) and muscle wasting in cirrhosis. In bile duct ligated-cirrhotic rats, the increased circulating CD16+ (inflammatory) monocytes and its intracellular TNFα, NFκB, monocyte chemotactic protein (MCP-1) and iNOS levels were associated with increased circulating MCP-1/soluable intercellular cell adehesion molecule-1 (sICAM-1), pulmonary TNFα/NOx, up-regulated M1 polarization, exacerbated angiogenesis and hypoxemia (increased AaPO2) in bronchoalveolar lavage (BAL) fluid and pulmonary homogenates. Meanwhile, a significant correlation was noted between circulating CD16+ monocyte/M1 (%) macrophages in BAL; M1 (%) macrophages in BAL/pulmonary iNOS mRNA expression; pulmonary iNOS mRNA expression/relative pulmonary MVD; pulmonary NOx level/AaPO2; circulating CD16+ monocyte/M1 (%) macrophages in muscle homogenates; 3-nitrotyrosine (representative of peroxynitrite) concentration/M1 (%) macrophages in muscle homogenates. The in vitro data demonstrated an iNOS-dependent inhibition of thalidomide on the TNFα-stimulated angiogenesis and myogenesis in human pulmonary artery endothelial cells (HPAECs) and C2C12 myoblasts. Significantly, the co-culture of CD16+ monocyte from different rats with HPAECs, or co-culture of supernatant of above mixed cultures with HPAECs or C2C12 myoblasts stimulated angiogenesis, migration and myogenesis. Our findings demonstrate that TNFα inhibitor thalidomide markedly diminishes the severity of experimental HPS and muscle wasting by down-regulation of common peripheral and local NFκB-iNOS pathway.
269. Acetyl-11-Keto-β-Boswellic Acid Attenuates Prooxidant and Profibrotic Mechanisms Involving Transforming Growth Factor-β1, and Improves Vascular Remodeling in Spontaneously Hypertensive Rats.
作者: Peijin Shang.;Wenxing Liu.;Tianlong Liu.;Yikai Zhang.;Fei Mu.;Zhihui Zhu.;Lingfei Liang.;Xiaohu Zhai.;Yi Ding.;Yuwen Li.;Aidong Wen.
来源: Sci Rep. 2016年6卷39809页
Vascular remodeling is an important complication of hypertension with oxidative stress-related profibrotic pathways involved. The transforming growth factor β1 (TGF-β1) has been shown to be a potential target of vasoprotection, and has multiple roles in vascular remodeling. Acetyl-11-Keto-β-Boswellic Acid (AKBA) is one of the active principles of Boswellic acids, and shows antioxidant activity in many diseases. The study is to determine effects of AKBA on systemic oxidative stress of hypertension and vascular remodeling. In the experiments, spontaneously hypertensive rats (SHR) were used. And in vitro, fibroblast was pretreated with AKBA before Ang II stimuli. In the results, treatment of AKBA markedly reduced oxidative stress, and decreased vascular remodeling by restoring vascular wall parameters and improving vascular reactivity. AKBA dramatically reduced TGF-β1 and Smad3 expression, as shown in immunofluorescence and immunohistochemistry. In cultured fibroblast, AKBA decreased intracellular ROS levels. Cell viability and proliferation, as well as migration were inhibited by AKBA. Additionally, treatment of AKBA significantly decreased TGF-β1 secretion in culture supernatant. Expression of TGF-β1, Smad3, P-Smad3 and Smad7 were also decreased by AKBA in fibroblast. In conclusion, AKBA is able to attenuate oxidative stress and profibrotic mechanisms, and improve vascular remodeling in hypertension through TGF-β1/Smad3 pathway.
270. Melatonin implantation improved the egg-laying rate and quality in hens past their peak egg-laying age.
作者: Yaxiong Jia.;Minghui Yang.;Kuanfeng Zhu.;Liang Wang.;Yukun Song.;Jing Wang.;Wenxiang Qin.;Zhiyuan Xu.;Yu Chen.;Guoshi Liu.
来源: Sci Rep. 2016年6卷39799页
The egg-laying rates of hens approximately 470 days of age exhibited a positive correlation to blood melatonin levels. The hens with an egg-laying rate <30%, 30~90% and ≥90% had blood melatonin levels of 5.8 ± 2.6, 74.0 ± 32.9 and 445.9 ± 115.3 ng/ml, respectively. When 10 mg of melatonin was implanted into the hens at 300, 360, 470 and 550 days of age, the egg-laying rates increased 4.63 ± 0.46%, 8.38 ± 1.45%, 4.93 ± 0.85% and 7.93 ± 0.91%, respectively, compared to that of the controls. Melatonin implantation in hens at 300-470 days of age was observed to enhance egg production and reduce the rate of appearance of sharpei eggs. Melatonin (10 mg) implanted in hens 360 days of age did not influence the blood levels of progesterone (P4) or the gene expression levels of ovarian follicle stimulating hormone receptor (FSHR), luteinizing hormone receptor (LHR), oestradiol receptor alpha (ERα), superoxide dismutase 2 (SOD2) or melatonin receptor 1 (MT1). In contrast, melatonin significantly elevated the serum oestradiol-17β (E2) content, down-regulated the gene expression of gonadotropin-inhibitory hormone receptor (GnIHR), and enhanced the expression of melatonin receptor 2 (MT2). This result indicates that the improved egg-laying rate by melatonin was the result of increased serum oestradiol and decreased ovarian GnIHR. These alterations may be mediated by MT2 activation.
271. The overexpressed functional transient receptor potential channel TRPM2 in oral squamous cell carcinoma.
作者: Ling-Yan Zhao.;Wan-Lin Xu.;Zeng-Qi Xu.;Cui Qi.;Yang Li.;Jie Cheng.;Lai-Kui Liu.;Yu-Nong Wu.;Jun Gao.;Jin-Hai Ye.
来源: Sci Rep. 2016年6卷38471页
TRPM2, one member of the transient receptor potential (TRP) protein super-family, is a Ca2+-permeable channel that is activated by oxidative stress and confers susceptibility to cell death. In the human tongue specimens of carcinoma and the tongue carcinoma SCC cell lines, we observed the enhanced expression of TRPM2. By means of the whole-cell electrophysiological recording, the ADPR-induced currents mediated by TRPM2 were recorded in cultured SCC9 cells. Moreover, after H2O2 treatment for 24 hours, the apoptotic number of SCC9 cells was significantly increased. However, the selectively knocked-down TRPM2 with the small interfering RNA technique inhibited the survival and migration of the SCC9 cancer cells, which was independent of the p53-p21 pathway, since the expression of p21 was enhanced after TRPM2 knockdown. Furthermore, the sub-cellular localization of TRPM2 was remarkably different between cancerous and non-cancerous cells. A significant amount of the TRPM2 proteins were located in the nuclei in cancer cells. All these data suggest that TRPM2 is essential for the survival and migration of SCC cancer cells and may be a potential target for the selective treatment of tongue cancer.
272. Biallelic JAK1 mutations in immunodeficient patient with mycobacterial infection.
作者: Davide Eletto.;Siobhan O Burns.;Ivan Angulo.;Vincent Plagnol.;Kimberly C Gilmour.;Frances Henriquez.;James Curtis.;Miguel Gaspar.;Karolin Nowak.;Vanessa Daza-Cajigal.;Dinakantha Kumararatne.;Rainer Doffinger.;Adrian J Thrasher.;Sergey Nejentsev.
来源: Nat Commun. 2016年7卷13992页
Mutations in genes encoding components of the immune system cause primary immunodeficiencies. Here, we study a patient with recurrent atypical mycobacterial infection and early-onset metastatic bladder carcinoma. Exome sequencing identified two homozygous missense germline mutations, P733L and P832S, in the JAK1 protein that mediates signalling from multiple cytokine receptors. Cells from this patient exhibit reduced JAK1 and STAT phosphorylation following cytokine stimulations, reduced induction of expression of interferon-regulated genes and dysregulated cytokine production; which are indicative of signalling defects in multiple immune response pathways including Interferon-γ production. Reconstitution experiments in the JAK1-deficient cells demonstrate that the impaired JAK1 function is mainly attributable to the effect of the P733L mutation. Further analyses of the mutant protein reveal a phosphorylation-independent role of JAK1 in signal transduction. These findings clarify JAK1 signalling mechanisms and demonstrate a critical function of JAK1 in protection against mycobacterial infection and possibly the immunological surveillance of cancer.
273. Pleckstrin homology domain-containing protein PHLDB3 supports cancer growth via a negative feedback loop involving p53.
作者: Tengfei Chao.;Xiang Zhou.;Bo Cao.;Peng Liao.;Hongbing Liu.;Yun Chen.;Hee-Won Park.;Shelya X Zeng.;Hua Lu.
来源: Nat Commun. 2016年7卷13755页
The tumour suppressor p53 transactivates the expression of its target genes to exert its functions. Here, we identify a pleckstrin homology domain-containing protein (PHLDB3)-encoding gene as a p53 target. PHLDB3 overexpression increases proliferation and restrains apoptosis of wild-type p53-harboring cancer cells by reducing p53 protein levels. PHLDB3 binds to MDM2 (mouse double minute 2 homolog) and facilitates MDM2-mediated ubiquitination and degradation of p53. Knockdown of PHLDB3 more efficiently inhibits the growth of mouse xenograft tumours derived from human colon cancer HCT116 cells that contain wild type p53 compared with p53-deficient HCT116 cells, and also sensitizes tumour cells to doxorubicin and 5-Fluorouracil. Analysis of cancer genomic databases reveals that PHLDB3 is amplified and/or highly expressed in numerous human cancers. Altogether, these results demonstrate that PHLDB3 promotes tumour growth by inactivating p53 in a negative feedback fashion and suggest PHLDB3 as a potential therapeutic target in various human cancers.
275. Losartan Improves Palmitate-Induced Insulin Resistance in 3T3-L1 Adipocytes Through Upregulation of Src Phosphorylation.
Angiotensin II type 1 receptor blocker losartan has shown strongly anti-insulin resistance properties in vivo and in vitro; however, the underlying mechanisms are poorly understood. In this study, we demonstrate that losartan administration increased phosphorylation of Akt and its downstream Akt substrate of 160 kDa (AS160), enhanced plasma membrane translocation of glucose transporter type 4 (GLUT4), and increased glucose uptake, along with increased Src phosphorylation as well as reduced expression of docking protein 1(DOK1) in palmitate-treated 3T3-L1 adipocytes. The beneficial impacts of losartan on insulin signaling were diminished in Src-deficient 3T3-L1 adipocytes. In addition, suppressed expression of DOK1 by losartan was abolished by Src knockdown. Our results suggest that anti-insulin resistance ability of losartan is mediated by Src/DOK1/Akt pathway.
276. Effect of Fu-Zheng-Xiao-Liu Granules on Expression of Human Epidermal Growth Factor Receptor 2 (HER-2) and Proliferation and Apoptosis of Breast Cancer Cell Line SKBR-3.
作者: Ting Mo.;Shuangbing Yue.;Huan Tian.;Hong Lin.;Guanglu Zhang.;Zili Zhang.
来源: Med Sci Monit. 2016年22卷5068-5073页
BACKGROUND Previous research showed that granulized Fu-Zheng-Xiao-Liu has a significant effect on breast cancer. However, it remains unclear whether HER-2 plays a role in this anti-cancer effect. MATERIAL AND METHODS Serum of male SD rats administered Fu-Zheng-Xiao-Liu granules (SF) was prepared and used to treat HER-2 positive breast cancer cell line SKBR-3. PBS and herceptin were used as negative and positive controls, respectively. MTT was used to detect the proliferation of SKBR-3 cells. Flow cytometry was used to measure the apoptosis of SKBR-3 cells. Western blot and immunofluorescence were used to measure the expression change of HER-2. RESULTS Serum of male SD rats administered Fu-Zheng-Xiao-Liu granules had significantly reduced HER-2 expression at both mRNA level and protein level, significantly inhibited proliferation of SKBR-3 cells, and significantly increased apoptosis of SKBR-3 cells, compared to that of the blank control group or serum control group. CONCLUSIONS Fu-Zheng-Xiao-Liu granules affect proliferation and apoptosis through inhibition of HER-2 transcription and translation, providing an experimental basis for further study of the mechanism by which Fu-Zheng-Xiao-Liu granules affect breast cancer.
277. Baicalein Inhibits Epithelial to Mesenchymal Transition via Downregulation of Cyr61 and LOXL-2 in MDA-MB231 Breast Cancer Cells.
Epithelial-mesenchymal transition (EMT) is a critical step in the acquisition of the migratory and invasive capabilities associated with metastatic competence. Cysteine-rich protein 61 (CCN1/Cyr61) has been implicated as an important mediator in the proliferation and metastasis of breast cancer. Hence, Cyr61 and associated pathways are attractive targets for therapeutic interventions directed against the EMT. In the present study, we report that baicalein significantly inhibits the expression of Cyr61 and migration and invasion of MDA-MB231 human breast cancer cells. Exposure to baicalein led to increased E-cadherin expression, possibly due to the ubiquitination of Snail and Slug, which was mediated by the Cyr61/Akt/glycogen synthase kinase 3β (GSK3β) pathway. Further analysis revealed that baicalein inhibited the expression of lysyl oxidase like-2 (LOXL-2), which is a functional collaborator of Snail and Slug, and subsequently attenuated the direct interaction between LOXL-2 and Snail or Slug, thereby enhancing GSK3β-dependent Snail and Slug degradation. Our findings provide new insights into the antimetastatic mechanism of baicalein and may contribute to its beneficial use in breast cancer therapies.
278. Dual effects of fructose on ChREBP and FoxO1/3α are responsible for AldoB up-regulation and vascular remodelling.
作者: Wei Cao.;Tuanjie Chang.;Xiao-Qiang Li.;Rui Wang.;Lingyun Wu.
来源: Clin Sci (Lond). 2017年131卷4期309-325页
Increased production of methylglyoxal (MG) in vascular tissues is one of the causative factors for vascular remodelling in different subtypes of metabolic syndrome, including hypertension and insulin resistance. Fructose-induced up-regulation of aldolase B (AldoB) contributes to increased vascular MG production but the underlying mechanisms are unclear. Serum levels of MG and fructose were determined in diabetic patients with hypertension. MG level had significant positive correlations with blood pressure and fructose level respectively. C57BL/6 mice were fed with control or fructose-enriched diet for 3 months and ultrasonographic and histologic analyses were performed to evaluate arterial structural changes. Fructose-fed mice exhibited hypertension and high levels of serum MG with normal glucose level. Fructose intake increased blood vessel wall thickness and vascular smooth muscle cell (VSMC) proliferation. Western blotting and real-time PCR analysis revealed that AldoB level was significantly increased in both the aorta of fructose-fed mice and the fructose-treated VSMCs, whereas aldolase A (AldoA) expression was not changed. The knockdown of AldoB expression prevented fructose-induced MG overproduction and VSMC proliferation. Moreover, fructose significantly increased carbohydrate-responsive element-binding protein (ChREBP), phosphorylated FoxO1/3α and Akt1 levels. Fructose induced translocation of ChREBP from the cytosol to nucleus and activated AldoB gene expression, which was inhibited by the knockdown of ChREBP. Meanwhile, fructose caused FoxO1/3α shuttling from the nucleus to cytosol and inhibited its binding to AldoB promoter region. Fructose-induced AldoB up-regulation was suppressed by Akt1 inhibitor but enhanced by FoxO1/3α siRNA. Collectively, fructose activates ChREBP and inactivates FoxO1/3α pathways to up-regulate AldoB expression and MG production, leading to vascular remodelling.
279. Use of antisense oligonucleotides to correct the splicing error in ISCU myopathy patient cell lines.
作者: Gregory P Holmes-Hampton.;Daniel R Crooks.;Ronald G Haller.;Shuling Guo.;Susan M Freier.;Brett P Monia.;Tracey A Rouault.
来源: Hum Mol Genet. 2016年25卷23期5178-5187页
ISCU myopathy is an inherited disease that primarily affects individuals of northern Swedish descent who share a single point mutation in the fourth intron of the ISCU gene. The current study shows correction of specific phenotypes associated with disease following treatment with an antisense oligonucleotide (ASO) targeted to the site of the mutation. We have shown that ASO treatment diminished aberrant splicing and increased ISCU protein levels in both patient fibroblasts and patient myotubes in a concentration dependent fashion. Upon ASO treatment, levels of SDHB in patient myotubular cell lines increased to levels observed in control myotubular cell lines. Additionally, we have shown that both patient fibroblast and myotubular cell lines displayed an increase in complex II activity with a concomitant decrease in succinate levels in patient myotubular cell lines after ASO treatment. Mitochondrial and cytosolic aconitase activities increased significantly following ASO treatment in patient myotubes. The current study suggests that ASO treatment may serve as a viable approach to correcting ISCU myopathy in patients.
280. Structure-activity relationship for branched oxyquinoline HIF activators: Effect of modifications to phenylacetamide "tail".
作者: A A Poloznikov.;A A Zakhariants.;S V Nikulin.;N A Smirnova.;D M Hushpulian.;I N Gaisina.;A G Tonevitsky.;V I Tishkov.;I G Gazaryan.
来源: Biochimie. 2017年133卷74-79页
HIF prolyl hydroxylase is a major regulator of HIF stability. Branched tail oxyquinolines have been identified as specific inhibitors of HIF prolyl hydroxylase and recently demonstrated clear benefits in various scenarios of neuronal failure. The structural optimization for branched tail oxyquinolines containing an acetamide bond has been performed in the present study using HIF1 ODD-luc reporter assay. The special attention has been paid to the length of a linker between acetamide group and phenyl ring, as well as substitutions in the phenyl ring in the other branch of the tail. The optimized version of branched tail oxyquinolines is 3-fold more potent than the original one identified before and shows a submicromolar EC50 in the reporter assay. The compounds have been studied in a "liver-on-a-chip" device to question their hepatotoxicity towards differentiated human HepaRG "hepatocytes": the absence of hepatotoxicity is observed up to 200 μM concentrations for all studied derivatives of branched tail oxyquinolines.
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