Gemcitabine sensitizes lung cancer cells to Fas/FasL system-mediated killing

PubMed Central

Siena, Liboria; Pace, Elisabetta; Ferraro, Maria; Di Sano, Caterina; Melis, Mario; Profita, Mirella; Spatafora, Mario; Gjomarkaj, Mark

2014-01-01

Gemcitabine is a chemotherapy agent commonly used in the treatment of non-small cell lung cancer (NSCLC) that has been demonstrated to induce apoptosis in NSCLC cells by increasing functionally active Fas expression. The aim of this study was to evaluate the Fas/Fas ligand (FasL) system involvement in gemcitabine-induced lung cancer cell killing. NSCLC H292 cells were cultured in the presence or absence of gemcitabine. FasL mRNA and protein were evaluated by real-time PCR, and by Western blot and flow cytometry, respectively. Apoptosis of FasL-expressing cells was evaluated by flow cytometry, and caspase-8 and caspase-3 activation by Western blot and a colorimetric assay. Cytotoxicity of lymphokine-activated killer (LAK) cells and malignant pleural fluid lymphocytes against H292 cells was analysed in the presence or absence of the neutralizing anti-Fas ZB4 antibody, by flow cytometry. Gemcitabine increased FasL mRNA and total protein expression, the percentage of H292 cells bearing membrane-bound FasL (mFasL) and of mFasL-positive apoptotic H292 cells, as well as caspase-8 and caspase-3 cleavage. Moreover, gemcitabine increased CH11-induced caspase-8 and caspase-3 cleavage and proteolytic activity. Cytotoxicity of LAK cells and pleural fluid lymphocytes was increased against gemcitabine-treated H292 cells and was partially inhibited by ZB4 antibody. These results demonstrate that gemcitabine: (i) induces up-regulation of FasL in lung cancer cells triggering cell apoptosis via an autocrine/paracrine loop; (ii) induces a Fas-dependent apoptosis mediated by caspase-8 and caspase-3 activation; (iii) enhances the sensitivity of lung cancer cells to cytotoxic activity of LAK cells and malignant pleural fluid lymphocytes, partially via Fas/FasL pathway. Our data strongly suggest an active involvement of the Fas/FasL system in gemcitabine-induced lung cancer cell killing. PMID:24128051

Fas/Fas Ligand pathways gene polymorphisms in pediatric renal allograft rejection.

PubMed

Fadel, Fatina I; Elshamaa, Manal F; Salah, Ahmed; Nabhan, Marwa; Rasheed, Maha; Kamel, Solaf; Kandil, Dina; Thabet, Eman H

2016-07-01

An essential milestone in pediatric transplantation is to find noninvasive biomarkers to monitor acute rejection (AR). In this retrospective (Case-control) study, we examined the role of Fas -670A/G and Fas Ligand (FasL) -843C/T gene polymorphisms in allograft nephropathy in pediatric renal transplant recipients. In 47 pediatric kidney transplant recipients and 20 healthy controls, Fas -670A/G and FasL -843C/T gene polymorphisms as well as serum soluble Fas Ligand level (sFasL) were measured. Serum sFasL levels were significantly higher in transplant recipients children than that in controls (548.25±298.64pg/ml vs 143.17±44.55pg/ml, p=0.0001). There was no significant difference between patients with AR and those without AR in regards to serum sFasL levels (567.70±279.87pg/ml vs 507.85±342.80pg/ml, p=0.56). Fas -670A/G genotypes or alleles were not significantly different between controls and transplant recipients and among transplant recipients with and without AR. (P>0.05 for all). FasL -843C/T genotypes were not different between transplant recipients and controls and among transplant recipients with and without AR (P>0.05 for all). However, Frequency of C allele in transplant patients was significantly higher than that in the control group (44.68% vs 25%, P=0.03). FasL -843C/T alleles were significantly different between patients with and without AR (P=0.03). The percentages of C allele were higher in children with AR (58.82% vs 36.67%). We found that serum FasL and serum creatinine were variables that were independently associated with AR. This study suggests that FasL gene polymorphisms in peripheral blood might be accurate in detecting cellular AR. Copyright © 2016 Elsevier B.V. All rights reserved.

Anti-Fas Antibody Conjugated Nanoparticles Enhancing the Antitumor Effect of Camptothecin by Activating the Fas-FasL Apoptotic Pathway.

PubMed

Yu, Hongliang; He, Jian; Lu, Qian; Huo, Da; Yuan, Shanmei; Zhou, Zhengyang; Xu, Peipei; Hu, Yong

2016-11-09

Emerging evidence suggest that the introduction of Fas ligand (FasL) can enhance the Fas-dependent apoptosis and induce durable immune responses against tumor. However, selective triggering of apoptosis in tumor cells while sparing normal cells remains a great challenge for the application of FasL-based therapeutic strategies. Herein, smart nanoparticles (NPs) with a sandwich structure were fabricated. These NPs consist of a matrix metalloproteinase (MMP) cleavable PEG outer layer, an anti-Fas antibody middle layer, and a camptothecin (CPT)-loaded inner core. They could accumulate at a tumor site by the enhanced permeability and retention (EPR) effect. The removable PEG layer protects the cytotoxic anti-Fas antibody from premature contact with normal tissues, thus avoiding the unexpected lethal side effect before they reach the tumor site. Due to the high level of MMP expressed by tumor cells inside the tumor tissue, these NPs would shed their PEG layers, resulting in the exposure of anti-Fas antibody to bind the Fas receptor and triggering the apoptosis of tumor cells. Results of Western blot confirmed that these NPs could mimic the function of activated cytotoxic lymphocyte (CTL) to activate the Fas-FasL apoptosis pathway of tumor cells. With the aid of CPT payload, these anti-Fas antibody conjugated NPs achieved a high tumor inhibition in the B16 allograft tumor animal model. The design of these NPs provides a method for delivering cytotoxic ligand to targeting tissue, which may be valuable in cancer therapy.

Involvement of Fas/FasL pathway in the murine model of atopic dermatitis.

PubMed

Bień, Karolina; Żmigrodzka, Magdalena; Orłowski, Piotr; Fruba, Aleksandra; Szymański, Łukasz; Stankiewicz, Wanda; Nowak, Zuzanna; Malewski, Tadeusz; Krzyżowska, Małgorzata

2017-08-01

The aim of this study was to elucidate the role of apoptosis mediated through Fas/FasL pathway using the mouse model of atopic dermatitis (AD). AD was induced by epicutaneous application of ovalbumin (OVA) in wild-type C57BL/6, B6. MRL-Faslpr/J (Fas-) and B6Smn.C3-Faslgld/J (FasL-) mouse strains. Skin samples were subjected to staining for Fas/FasL expression, M30 epitope and assessment of inflammatory response via immunohistochemical staining. Cytokine and chemokine production was assessed by real-time PCR. In comparison to wild-type mice, OVA sensitization of Fas- and FasL-deficient mice led to increased epidermal and dermal thickness, collagen deposition and local inflammation consisting of macrophages, neutrophils and CD4+ T cells. Fas- and FasL-deficient mice showed increased total counts of regulatory T cells (Tregs) and IgE levels in blood as well as increased expression of IL-1β, IL-4, IL-5, IL-13 and TGF-1β mRNA in comparison to wild-type mice. On the other hand, expression of CXCL9 and CXCL10, IL-17 mRNAs in the skin samples in Fas- and FasL-deficient mice was decreased. Our results show that lack of the Fas-induced apoptosis leads to exacerbation of AD characteristics such as Th2 inflammation and dermal thickening. Therefore, Fas receptor can play an important role in AD pathogenesis by controlling development of the local inflammation.

Relationship between Fas and Fas Ligand gene polymorphisms and pre-eclampsia.

PubMed

Masoumi, Elham; Tavakkol-Afshari, Jalil; Nikpoor, Amin Reza; Ghaffari-Nazari, Haniyeh; Tahaghoghi-Hajghorbani, Sahar; Jalali, Seyed Amir

2016-10-01

In normal pregnancy, the Th1 subtype, responsible for the production of inflammatory cytokines, is reduced, and the Th2 subtype is increased to prohibit inflammation. In pre-eclampsia, the Th1 cell population is increased; thus, subsequent inflammation and trophoblast destruction occur. Polymorphisms in the Fas and Fas Ligand (FasL) promoter regions can influence Fas and FasL expression and accused to increase of Th1 subtype. DNA samples from 153 pregnant women with pre-eclampsia and 140 controls were genotyped through polymerase chain reaction-restriction fragment length polymorphism. A Fisher's exact test was used to compare the distribution of individual polymorphisms. Fas-1377 AA, AG and GG genotypes were observed in 2.61%, 18.30% and 79.08% in the pre-eclampsia group opposed to 0%, 27.14% and 72.85% in the control group (P = 0.037), respectively. Fas-670 AA, AG and GG genotypes were observed in 37.9%, 41.8% and 20.3% of pre-eclampsia patients compared with 33.6%, 50.7% and 15.7% in healthy pregnant women (P = 0.291), respectively. No statically significant differences in the FasL-844 genotype were observed between the groups (P = 0.69). The Fas-1377G > A polymorphism is associated with a higher risk of pre-eclampsia. © 2016 Japan Society of Obstetrics and Gynecology.

Prognostic significance of Fas and Fas ligand system-associated apoptosis in gastric cancer.

PubMed

Ohno, S; Tachibana, M; Shibakita, M; Dhar, D K; Yoshimura, H; Kinugasa, S; Kubota, H; Masunaga, R; Nagasue, N

2000-12-01

Previous studies indicate that gastric carcinomas express Fas ligand and down-regulate Fas to escape from the host immune attack; however, the prognostic importance of Fas/FasL expression in this tumor is yet to be evaluated. Specimens from 87 gastric carcinoma patients of different stages treated in a defined period with curative intent were evaluated for apoptosis, Fas, FasL, and CD8 expression using an immunohistochemical method. The percentage of terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL)-positive apoptotic cells expressed as apoptotic index (AI) was higher in 43 patients when the cut-off value was set at the median value. There were no significant correlations between AI and clinicopathologic parameters. Thirty-nine patients showed a high number of CD8+ cells within cancer nests. Positive FasL and Fas expression was seen in 53 and 72 patients, respectively. CD8 and FasL expressions were related only to patients' age. Fas expression had significant correlations with tumor invasion and Lauren classification. There were significant direct correlations between AI and number of nest CD8+ cells and between AI and grade of Fas expression. Apoptotic index, pT stage, CD8 expression, and Fas expression were identified as independent prognostic factors. Spontaneous apoptosis in gastric carcinoma may be an independent prognosticator for survival and is significantly influenced by tumor Fas expression and number of nest CD8 + cells.

Inhibition of Fas (CD95) expression and Fas-mediated apoptosis by oncogenic Ras.

PubMed

Fenton, R G; Hixon, J A; Wright, P W; Brooks, A D; Sayers, T J

1998-08-01

The ras oncogene plays an important role in the multistep progression to cancer by activation of signal transduction pathways that contribute to aberrant growth regulation. Although many of these effects are cell autonomous, the ras oncogene also regulates the expression of genes that alter host/tumor interactions. We now extend the mechanisms through which ras promotes tumor survival by demonstrating that oncogenic Ras inhibits expression of the fas gene and renders Ras-transformed cells resistant to Fas-induced apoptosis. A panel of Ras-transformed clones exhibited a marked inhibition in fas mRNA and Fas cell surface expression as compared with untransformed parental cell lines. Fas expression was induced by culture in the presence of IFN-gamma + tumor necrosis factor alpha; however, the maximal level attained in Ras transformants was approximately 10-fold below the level of untransformed cells. Whereas untransformed cells were sensitive to apoptotic death induced by cross-linking surface Fas (especially after cytokine treatment), Ras-transformed cells were very resistant to Fas-induced death even under the most stringent assay conditions. To demonstrate that this resistance was mediated by oncogenic Ras and not secondary genetic events, pools of Ras-transformed cells were generated using a highly efficient retroviral transduction technique. Transformed pools were assayed 6 days after infection and demonstrated a marked decrease in fas gene expression and Fas-mediated apoptosis. Oncogenic Ras did not promote general resistance to apoptosis, because ectopic expression of a fas cDNA in Ras-transformed cells restored sensitivity to Fas-induced apoptosis. These data indicate that oncogenic Ras inhibits basal levels of expression of the fas gene, and although cytokine signal transduction pathways are functional in these cells, the level of surface Fas expression remains below the threshold required for induction of apoptosis. These data identify a mechanism by which

Radiation and stress-induced apoptosis: A role for Fas/Fas ligand interactions

PubMed Central

Reap, Elizabeth A.; Roof, Kevin; Maynor, Kenrick; Borrero, Michelle; Booker, Jessica; Cohen, Philip L.

1997-01-01

The lpr gene encodes a defective form of Fas, a cell surface protein that mediates apoptosis. This defect blocks apoptotic deletion of autoreactive T and B cells, leading to lymphoproliferation and lupus-like autoantibody production. The effects of the lpr Fas mutation on other kinds of physiologically relevant apoptosis are largely undocumented. To assess whether some of the apoptosis known to occur after ionizing radiation might be mediated by Fas/Fas ligand (FasL) interactions, we quantitated in vitro apoptosis by flow cytometry measurement of DNA content in splenic T and B cells from irradiated 5- to 8-month-old B6/lpr mice. Total apoptosis of both lpr and control cells was substantial after treatment; however there was a significant difference between B6 (73%) and lpr (25%) lymphocyte apoptosis. Thy1, CD4, CD8, and IgM cells from lpr showed much lower levels of apoptosis than control cells after irradiation. Apoptosis induced by heat shock was also impaired in lpr. The finding that γ-irradiation increased Fas expression on B6 cells and that irradiation-induced apoptosis could be blocked with a Fas–Fc fusion protein further supported the possible involvement of Fas in this form of apoptosis. Fas/FasL interactions may thus play an important role in identifying and eliminating damaged cells after γ-irradiation and other forms of injury. PMID:9159145

FAS and FAS-L Genotype and Expression in Patients With Recurrent Pregnancy Loss

PubMed Central

Banzato, Priscilla Chamelete Andrade; Daher, Silvia; Traina, Évelyn; Torloni, Maria Regina; Gueuvoghlanian-Silva, Bárbara Yasmin; Puccini, Renata Fiorini; Pendeloski, Karen Priscilla Tezotto

2013-01-01

We assessed FAS and FAS-L gene polymorphisms and messenger RNA (mRNA) levels in patients with recurrent pregnancy loss (RPL). This case–control study compared 129 women with RPL with 235 healthy multiparous women (control group). Genomic DNA and total mRNA were extracted from whole blood, and polymorphisms genotyping was performed by polymerase chain reaction (PCR). Messenger RNA expression levels were analyzed by real-time PCR. Data were analyzed by chi-square and Fisher exact tests; P < .05 was considered significant. There were no significant differences in the FAS (670 A/G) genotype or allelic frequencies between the RPL and control groups. We found significant differences in the FAS-L (844 C/T) genotype and allelic frequencies between women with RPL and controls. Patients with RPL had significantly higher FAS-L expression. Our data suggest that FAS-L gene polymorphism is associated with increased susceptibility to RPL. Moreover, women with RPL seem to abnormally express FAS-FAS-L molecules. PMID:23420824

NF-κB Directly Regulates Fas Transcription to Modulate Fas-mediated Apoptosis and Tumor Suppression*

PubMed Central

Liu, Feiyan; Bardhan, Kankana; Yang, Dafeng; Thangaraju, Muthusamy; Ganapathy, Vadivel; Waller, Jennifer L.; Liles, Georgia B.; Lee, Jeffrey R.; Liu, Kebin

2012-01-01

Fas is a member of the death receptor family. Stimulation of Fas leads to induction of apoptotic signals, such as caspase 8 activation, as well as “non-apoptotic” cellular responses, notably NF-κB activation. Convincing experimental data have identified NF-κB as a critical promoter of cancer development, creating a solid rationale for the development of antitumor therapy that suppresses NF-κB activity. On the other hand, compelling data have also shown that NF-κB activity enhances tumor cell sensitivity to apoptosis and senescence. Furthermore, although stimulation of Fas activates NF-κB, the function of NF-κB in the Fas-mediated apoptosis pathway remains largely undefined. In this study, we observed that deficiency of either Fas or FasL resulted in significantly increased incidence of 3-methylcholanthrene-induced spontaneous sarcoma development in mice. Furthermore, Fas-deficient mice also exhibited significantly greater incidence of azoxymethane and dextran sodium sulfate-induced colon carcinoma. In addition, human colorectal cancer patients with high Fas protein in their tumor cells had a longer time before recurrence occurred. Engagement of Fas with FasL triggered NF-κB activation. Interestingly, canonical NF-κB was found to directly bind to the FAS promoter. Blocking canonical NF-κB activation diminished Fas expression, whereas blocking alternate NF-κB increased Fas expression in human carcinoma cells. Moreover, although canonical NF-κB protected mouse embryo fibroblast (MEF) cells from TNFα-induced apoptosis, knocking out p65 diminished Fas expression in MEF cells, resulting in inhibition of FasL-induced caspase 8 activation and apoptosis. In contrast, knocking out p52 increased Fas expression in MEF cells. Our observations suggest that canonical NF-κB is a Fas transcription activator and alternate NF-κB is a Fas transcription repressor, and Fas functions as a suppressor of spontaneous sarcoma and colon carcinoma. PMID:22669972

Dysregulation of the Fas/FasL system in an experimental animal model of HELLP syndrome.

PubMed

Gibbens, Jacob; Morris, Rachael; Bowles, Teylor; Spencer, Shauna-Kay; Wallace, Kedra

2017-04-01

Placental FasL is up-regulated in women with HELLP (hemolysis elevated liver enzyme and low platelet) syndrome and has been proposed to contribute to the liver damage seen in these patients. This study aimed to determine if an experimental rodent model of HELLP also had dysregulation of Fas/FasL compared to normal pregnant (NP) rats. We also set out to determine if blockade of the endothelin system regulated Fas/FasL expression in HELLP rats. On gestational day (GD) 12, sEng (7ug/kg) and sFlt-1 (4.7ug/kg) infusion began via mini-osmotic pump into NP rats. On GD19 plasma and tissue were collected and FasL and Fas were measured via enzyme linked immunosorbent assay and gene expression via real-time PCR. HELLP rats had significantly more circulating and placental FasL compared to NP rats, whereas hepatic FasL was decreased and placental Fas was increased compared to NP rats. Administration of an endothelin A receptor antagonist (ET A ) beginning on GD12 significantly decreased placental expression of Fas in HELLP rats. Liver mRNA transcript of Fas was significantly increased in HELLP rats compared to NP rats. These data suggest that rats in this experimental model of HELLP syndrome have abnormal expression of the Fas/FasL system. Future studies will examine the sources of Fas/FasL dysregulation in this model and if blockade could reduce some of the inflammation and hypertension associated with HELLP syndrome. Copyright © 2017 International Society for the Study of Hypertension in Pregnancy. Published by Elsevier B.V. All rights reserved.

Expression of ADAM10, Fas, FasL and Soluble FasL in Patients with Oral Squamous Cell Carcinoma (OSCC) and their Association with Clinical-Pathological Parameters.

PubMed

Zepeda-Nuño, José Sergio; Guerrero-Velázquez, Celia; Del Toro-Arreola, Susana; Vega-Magaña, Natali; Ángeles-Sánchez, Julián; Haramati, Jesse; Pereira-Suárez, Ana L; Bueno-Topete, Miriam R

2017-04-01

ADAM10 has been implicated in the progression of various solid tumors. ADAM10 regulates the cleavage of the FasL ectodomain from the plasma membrane of different cell types, generating the soluble FasL fragment (sFasL). Currently, there are few studies in oral squamous cell carcinoma (OSCC) that correlate levels of ADAM10 and FasL in the tumor microenvironment with clinical parameters of the disease. To determine the expression of ADAM10, Fas, FasL and sFasL in patients with OSCC and its association with TNM stage. Twenty-five patients with OSCC and 25 healthy controls were included. Biopsies of tumor tissue from patients with OSCC and buccal mucosa in controls were obtained. ADAM10, Fas, and FasL were analyzed by Western blotting. sFasL was quantified by ELISA. ADAM10 and Fas decreased significantly in OSCC compared with controls. Relatedly, within the OSCC group, Fas and ADAM10 decreased in accordance with tumor disease stage; in stages I/II, as well as in tumors of smaller diameter (T1-T2), ADAM10 showed higher levels when compared to patients with T3-T4 tumors and in stage III-IV. FasL in the tumor microenvironment and serum FasL showed no significant differences between both groups. Levels of complete FasL and cleaved FasL were positively correlated in controls; this correlation is preserved in patients with tumors in early stages (I-II), but is lost in later stage (III-IV). The dysregulation of ADAM10, Fas and FasL could be useful indicators of the progression and severity of OSCC.

[Gene expression of H-FABP and FAS and its clinicopathological significance in breast infiltrating ductal carcinoma].

PubMed

Li, Hua; Lü, Qing; Xue, Hui; Dong, Li-hua; Yang, Hui-jun

2008-07-01

To detect the expression of Heart or Muscle Fatty acid binding protein (H-FABP) and fatty acid synthase (FAS) in human breast cancer cells. The expression levels of FAS and H-FABP in 81 ductal infiltrating carcinoma (DIC) were detected by RT-PCR, immunohistochemistry and Western blot analysis. The possible associations of the expression of the two proteins with major clinicopathological factors were analyzed. The expression of both H-FABP and FAS increased in DIC cells than in adjacent normal cells. But less H-FABP and FAS were found in grade III DIC than in grade I and grade II DIC (P < 0.05). There was a positive correlation between the expression of H-FABP and FAS. No correlations between the expressions of two genes with other clinicopathological factors were found. The higher expression of H-FABP in grade I and II DIC suggests an early increased response to the over-expression of FAS. The parallel increase of H-FABP and FAS expressions marks increased breast cancer risk.

Association between Fas/FasL gene polymorphism and musculoskeletal degenerative diseases: a meta-analysis.

PubMed

Huang, Donghua; Xiao, Jinrong; Deng, Xiangyu; Ma, Kaige; Liang, Hang; Shi, Deyao; Wu, Fashuai; Shao, Zengwu

2018-05-07

It was reported that Fas (rs1800682, rs2234767) and FasL (rs5030772, rs763110) gene polymorphism might be related to the risk of musculoskeletal degenerative diseases (MSDD), such as osteoarthritis (OA), intervertebral disc degeneration (IVDD) and rheumatoid arthritis (RA). However, data from different studies was inconsistent. Here we aim to elaborately summarize and explore the association between the Fas (rs1800682, rs2234767) and FasL (rs5030772, rs763110) and MSDD. Literatures were selected from PubMed, Web of Science, Embase, Scopus and Medline in English and VIP, SinoMed, Wanfang and the China National Knowledge Infrastructure (CNKI) in Chinese up to August 21, 2017. All the researches included are case-control studies about human. We calculated the pooled odds ratios (ORs) with 95% confidence intervals (95% CI) to evaluate the strengths of the associations of Fas (rs1800682, rs2234767) and FasL (rs5030772, rs763110) polymorphisms with MSDD risk. Eleven eligible studies for rs1800682 with 1930 cases and 1720 controls, 6 eligible studies for rs2234767 with 1794 cases and 1909 controls, 3 eligible studies for rs5030772 with 367 cases and 313 controls and 8 eligible studies for rs763110 with 2010 cases and 2105 controls were included in this analysis. The results showed that the G allele of Fas (rs1800682) is associated with an increased risk of IVDD in homozygote and recessive models. The G allele of Fas (rs2234767) is linked to a decreased risk of RA but an enhanced risk of OA in allele and recessive models. In addition, the T allele of FasL (rs763110) is correlated with a reduced risk of IVDD in all of models. However, no relationship was found between FasL (rs5030772) and these three types of MSDD in any models. Fas (rs1800682) and FasL (rs763110) polymorphism were associated with the risk of IVDD and Fas (rs2234767) was correlated to the susceptibility of OA and RA. Fas (rs1800682) and Fas (rs2234767) are more likely to be associated with MSDD for Chinese

Inorganic arsenic exposure increased expression of Fas and Bax gene in vivo and vitro.

PubMed

He, Yuefeng; Zhang, Ruobing; Xiaoxiao, Song; Li, Shang; Xinan, Wu; Huang, Dahai

2018-06-01

Accumulating evidences have shown that apoptosis plays an important role in mediating the therapeutic effects and toxicity of arsenic. Fas and Bax genes are critical regulatory genes for apoptosis. In this study, we investigated the association between levels of Fas and Bax expression and the three arsenic species (inorganic arsenic (iAs), monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA)) in vivo and vitro. Three arsenic species in urine were measured and levels of Fas and Bax expression were examined by the quantitative real-time PCR (qPCR) for all subjects. We found that Fas and Bax mRNA expression in the exposed group were significantly higher than that in the control group. The levels of gene expression were positively correlated with the concentrations of urinary iAs, MMA and DMA in all subjects. Sodium arsenite induced Fas and Bax mRNA expression, then MMA and DMA did not induce mRNA expression in MDA-MB-231 and XWLC-05 cells. The findings of the present study indicated that iAs, MMA, and DMA had different effects on expression of Bax and Fas gene. Copyright © 2017. Published by Elsevier B.V.

Fas and FasL genetic polymorphisms in women with recurrent pregnancy loss: a case-control study.

PubMed

Han, Ae Ra; Choi, Young Min; Hong, Min A; Kim, Jin Ju; Lee, Sung Ki; Yang, Kwang Moon; Paik, Eun Chan; Jeong, Hyeon Jeong; Jun, Jong Kwan

2018-05-20

Aberrant apoptosis at the trophoblast-maternal interface and abnormal expression of Fas and Fas ligand (FasL) have been reported in complicated pregnancies with recurrent pregnancy losses (RPL) and preeclampsia. We assessed the prevalence of Fas and FasL genetic polymorphisms in Korean women with RPL and in fertile controls. In total, 306 women with RPL and 298 fertile controls were enrolled. Genotype distributions of Fas and FasL in RPL patients versus fertile controls were examined under the Hardy-Weinberg equilibrium. Fas -670 A/G genotype (AA versus AG versus GG, p = 0.340) and allele frequencies (A versus G, p = 0.412) were not different between the RPL and control groups. There was no difference in each Fas -1377 G/A and FasL -844 C/T genotype, and their allele frequencies. In addition, the unions of two zygosities of each genotype and their combined genotypes did not differ between two groups. No difference in the prevalence of Fas and FasL single-nucleotide polymorphisms (SNPs) was observed between women with RPL and fertile controls among Korean women. To determine the possibility of genetic polymorphisms in Fas and its ligand as risk factors for RPL, further studies in various races and a large study population are needed.

Fas/FasL gene polymorphism in patients with Hashimoto's thyroiditis in Turkish population.

PubMed

Erdogan, M; Kulaksizoglu, M; Ganidagli, S; Berdeli, A

2017-01-01

Hashimoto's disease is a polygenic disorder with complex etiopathogenesis. Apoptosis is proposed as one of its mechanisms. The Fas/Fas ligand cascade represents a major pathway initiating apoptosis. This study aims to evaluate the influence of Fas and FasL gene polymorphism in Hashimoto's thyroiditis in Turkish population. A total of 112 patients with Hashimoto's thyroiditis and 112 cases of healthy control people were included in this study. The evaluation of genotype for Fas -670 A/G and FasL 843 C/T gene polymorphism was performed by using PCR-RFLP method. The FAS genotype and gene allele frequency distribution did differ between the control group (AA 36.6 %, AG 50.0 %, GG 13.4 %, A 61.6 %, G 38.4 %) and the Hashimoto's thyroiditis patients (AA 21.4 %, AG 50.9 %, GG 27.7 %, A 46.9 %, G 53.1 %) (p < 0.01). The evaluation of FasL genotype and gene allele frequency did not show statistically significant difference between the patient group (CC 27.7 %, CT 45.5 %, TT 26.8 %, C 50.4 %, T 49.6 %) and control group (CC 33.9 %, CT 44.6 %, TT 21,4 %, C 56.3 %, T 43.8 %) (p > 0.05). Gene polymorphism of Fas and G allele frequency may play a role in the regulation of apoptosis in thyroid autoimmune disorders. There is a need for further studies to clarify the genetic role of apoptosis in HT.

Impaired Fas-Fas Ligand Interactions Result in Greater Recurrent Herpetic Stromal Keratitis in Mice

PubMed Central

Yin, Xiao-Tang; Keadle, Tammie L.; Hard, Jessicah; Herndon, John; Potter, Chloe A.; Del Rosso, Chelsea R.; Ferguson, Thomas A.; Stuart, Patrick M.

2015-01-01

Herpes simplex virus-1 (HSV-1) infection of the cornea leads to a potentially blinding condition termed herpetic stromal keratitis (HSK). Clinical studies have indicated that disease is primarily associated with recurrent HSK following reactivation of a latent viral infection of the trigeminal ganglia. One of the key factors that limit inflammation of the cornea is the expression of Fas ligand (FasL). We demonstrate that infection of the cornea with HSV-1 results in increased functional expression of FasL and that mice expressing mutations in Fas (lpr) and FasL (gld) display increased recurrent HSK following reactivation compared to wild-type mice. Furthermore, both gld and lpr mice took longer to clear their corneas of infectious virus and the reactivation rate for these strains was significantly greater than that seen with wild-type mice. Collectively, these findings indicate that the interaction of Fas with FasL in the cornea restricts the development of recurrent HSK. PMID:26504854

Impaired Fas-Fas Ligand Interactions Result in Greater Recurrent Herpetic Stromal Keratitis in Mice.

PubMed

Yin, Xiao-Tang; Keadle, Tammie L; Hard, Jessicah; Herndon, John; Potter, Chloe A; Del Rosso, Chelsea R; Ferguson, Thomas A; Stuart, Patrick M

2015-01-01

Herpes simplex virus-1 (HSV-1) infection of the cornea leads to a potentially blinding condition termed herpetic stromal keratitis (HSK). Clinical studies have indicated that disease is primarily associated with recurrent HSK following reactivation of a latent viral infection of the trigeminal ganglia. One of the key factors that limit inflammation of the cornea is the expression of Fas ligand (FasL). We demonstrate that infection of the cornea with HSV-1 results in increased functional expression of FasL and that mice expressing mutations in Fas (lpr) and FasL (gld) display increased recurrent HSK following reactivation compared to wild-type mice. Furthermore, both gld and lpr mice took longer to clear their corneas of infectious virus and the reactivation rate for these strains was significantly greater than that seen with wild-type mice. Collectively, these findings indicate that the interaction of Fas with FasL in the cornea restricts the development of recurrent HSK.

A lack of Fas/FasL signalling leads to disturbances in the antiviral response during ectromelia virus infection.

PubMed

Bień, K; Sobańska, Z; Sokołowska, J; Bąska, P; Nowak, Z; Winnicka, A; Krzyzowska, M

2016-04-01

Ectromelia virus (ECTV) is an orthopoxvirus (OPV) that causes mousepox, the murine equivalent of human smallpox. Fas receptor-Fas ligand (FasL) signaling is involved in apoptosis of immune cells and virus-specific cytotoxicity. The Fas/FasL pathway also plays an important role in controlling the local inflammatory response during ECTV infection. Here, the immune response to the ECTV Moscow strain was examined in Fas (-) (lpr), FasL (-) (gld) and C57BL6 wild-type mice. During ECTV-MOS infection, Fas- and FasL mice showed increased viral titers, decreased total numbers of NK cells, CD4(+) and CD8(+) T cells followed by decreased percentages of IFN-γ expressing NK cells, CD4(+) and CD8(+) T cells in spleens and lymph nodes. At day 7 of ECTV-MOS infection, Fas- and FasL-deficient mice had the highest regulatory T cell (Treg) counts in spleen and lymph nodes in contrast to wild-type mice. Furthermore, at days 7 and 10 of the infection, we observed significantly higher numbers of PD-L1-expressing dendritic cells in Fas (-) and FasL (-) mice in comparison to wild-type mice. Experiments in co-cultures of CD4(+) T cells and bone-marrow-derived dendritic cells showed that the lack of bilateral Fas-FasL signalling led to expansion of Tregs. In conclusion, our results demonstrate that during ECTV infection, Fas/FasL can regulate development of tolerogenic DCs and Tregs, leading to an ineffective immune response.

Fas and Fas ligand gene polymorphisms in Turkish patients with Familial Mediterranean Fever.

PubMed

Ozel, Emine Gulce; Duran, Gulay Gulbol; Celik, Muhammet Murat; Duran, Nizami; Gunesacar, Ramazan

2017-08-05

Familial Mediterranean Fever (FMF) is an autosomal recessive autoinflammatory disorder characterized by recurrent fever, serositis, abdominal pain, arthritis, arthralgia and erysipelas like erythema. Fas and Fas ligand molecules play a central role in the apoptosis signaling of various cell types including neutrophils. Neutrophils are the major cell population involved in acute inflammation in patients with FMF and the role of Fas and Fas ligand molecules in this cells of FMF patients may be crucial. Therefore, in the present study, we aimed to investigate whether the Fas cell surface receptor gene (FAS); NM_000043.5: c.-671A>G (rs1800682, MvaI) and Fas ligand gene (FASLG), NM_000639.2: c.-844C>T (rs763110, BsrD1) functional polymorphisms in patients with FMF and their relation to the main clinical features of the disease. The polymorphisms in the promoter regions of FAS c.-671A>G and FASLG c.-844C>T were investigated in 97 non-related FMF patients and 70 non-related healthy controls by using PCR-RFLP technique. The frequencies of FAS c-671AG genotype and G allele were not significantly different between FMF patients and healthy subjects. The frequency of FASLG -844TC genotype was found significantly different between the patients with FMF and healthy controls whereas T or C allele frequency was not significantly different between the groups. Haplotype frequencies of the studied polymorphisms were also not significantly different between FMF patients and controls. There were no correlations between the studied FAS c.-671A>G and FASLG c.-844C>T polymorphisms and the main clinical features of FMF such as fever, arthritis, abdominal and chest pain, arthralgia and erysipelas-like erythema. Our findings suggest that FAS c.-671AG genotype or G allele and FASLG c.-844 allele are not to be a risk factor, whereas FASLG c.-844TC genotype may be protective in the studied Turkish population. According to our results we may suggest that although not statistically significant

Quality evaluation of extemporaneous delayed-release liquid formulations of lansoprazole.

PubMed

Melkoumov, Alexandre; Soukrati, Amina; Elkin, Igor; Forest, Jean-Marc; Hildgen, Patrice; Leclair, Grégoire

2011-11-01

The quality attributes of extemporaneous delayed-release liquid formulations of lansoprazole for oral administration were evaluated. A novel liquid formulation (3 mg/mL) of Prevacid FasTab in an Ora-Blend vehicle was prepared and compared with the Prevacid FasTab 30 mg and Prevacid-sodium bicarbonate 1 M formulation (3 mg/mL). The latter formulation was combined with hydrochloric acid 0.1 N, and the remaining lansoprazole content was assayed by high-performance liquid chromatography (HPLC). A batch of delayed-release liquid formulation was prepared to evaluate content uniformity. For content assay, three samples were prepared for each evaluated condition and each sample was analyzed in triplicate by HPLC. The lansoprazole in the sodium bicarbonate formulation was extensively degraded by quantities of hydrochloric acid 0.1 N in excess of 100 mL. Storage time and temperature had a significant effect on lansoprazole stability in the Ora-Blend formulation. The drug remained stable for seven days when the formulation was stored at 4.5-5.5 °C, but storage at 21-22 °C or the reduction of pH with citric acid accelerated lansoprazole degradation. The amount of lansoprazole released from the Ora-Blend formulation during the buffer stage of the dissolution test decreased with increases in formulation storage time, in formulation storage temperature, and in the amount of lansoprazole released and degraded during the acid stage of the test. An extemporaneous formulation consisting of lansoprazole microgranules in Ora-Blend maintained acceptable quality attributes when stored for three days at 4.5-5.5 °C.

Mesangial cell Fas ligand: upregulation in human lupus nephritis and NF-kappaB-mediated expression in cultured human mesangial cells.

PubMed

Tsukinoki, Tomoko; Sugiyama, Hitoshi; Sunami, Reiko; Kobayashi, Mizuho; Onoda, Tetsuya; Maeshima, Yohei; Yamasaki, Yasushi; Makino, Hirofumi

2004-09-01

Fas ligand (FasL) is a well-known death factor; however, the role of FasL in the regulation of human glomerulonephritis remains unclear. We investigated the renal expression and localization of FasL in various forms of human glomerulonephritis by immunohistochemistry, utilizing confocal laser scanning microscopy. We further evaluated cytokine-induced FasL expression via nuclear factor (NF)kappaB in cultured human mesangial cells (HMC). The level of soluble FasL was measured by a specific enzyme-linked immunosorbent assay (ELISA). The frequency of glomerular FasL-positive cases was higher in lupus nephritis (37.9%) as compared with other forms of glomerulonephritis (8.7%). The glomerular FasL score in proliferative lupus nephritis was significantly higher than that in nonproliferative forms. Patients with a high apoptosis score, severe microhematuria, proteinuria, or decreased renal function had a high FasL score. Double immunolabelling demonstrated that the most prevalent phenotypes of FasL-positive cells were mesangial cells. In cultured HMC, interleukin (IL)1beta, lipopolysaccharide (LPS), or gamma interferon (IFN) upregulated membrane-bound FasL. IL1beta significantly, and LPS or gammaIFN weakly activated NFkappaB, but none of these agents activated NFkappaB/Rel-related nuclear factor of activated T cells (NFATc) or IFN regulatory factor-1. IL1beta-mediated NFkappaB was completely inhibited in the presence of lactacystin, a potent inhibitor of NFkappaB. Lactacystin-mediated inhibition of NFkappaB reduced FasL protein levels. Matrix metalloproteinase (MMP)-7, but not other MMPs (1, 2, 3, 8, or 9), significantly sensitized HMC to release soluble FasL after IL1beta stimulation. The results suggest that: (1) upregulation of mesangial FasL may contribute to the glomerular inflammation in proliferative lupus nephritis in vivo; (2) proinflammatory cytokines, in particular IL1beta, produced in nephritis can upregulate FasL via the transcription factor NFkappaB in HMC

Pigment Epithelial-derived Factor (PEDF)-triggered Lung Cancer Cell Apoptosis Relies on p53 Protein-driven Fas Ligand (Fas-L) Up-regulation and Fas Protein Cell Surface Translocation*

PubMed Central

Li, Lei; Yao, Ya-Chao; Fang, Shu-Huan; Ma, Cai-Qi; Cen, Yi; Xu, Zu-Min; Dai, Zhi-Yu; Li, Cen; Li, Shuai; Zhang, Ting; Hong, Hong-Hai; Qi, Wei-Wei; Zhou, Ti; Li, Chao-Yang; Yang, Xia; Gao, Guo-Quan

2014-01-01

Pigment epithelium-derived factor (PEDF), a potent antiangiogenesis agent, has recently attracted attention for targeting tumor cells in several types of tumors. However, less is known about the apoptosis-inducing effect of PEDF on human lung cancer cells and the underlying molecular events. Here we report that PEDF has a growth-suppressive and proapoptotic effect on lung cancer xenografts. Accordingly, in vitro, PEDF apparently induced apoptosis in A549 and Calu-3 cells, predominantly via the Fas-L/Fas death signaling pathway. Interestingly, A549 and Calu-3 cells are insensitive to the Fas-L/Fas apoptosis pathway because of the low level of cell surface Fas. Our results revealed that, in addition to the enhancement of Fas-L expression, PEDF increased the sensitivity of A549 and Calu-3 cells to Fas-L-mediated apoptosis by triggering the translocation of Fas protein to the plasma membrane in a p53- and FAP-1-dependent manner. Similarly, the up-regulation of Fas-L by PEDF was also mediated by p53. Furthermore, peroxisome proliferator-activated receptor γ was determined to be the upstream regulator of p53. Together, these findings uncover a novel mechanism of tumor cell apoptosis induced by PEDF and provide a potential therapeutic strategy for tumors that are insensitive to Fas-L/Fas-dependent apoptosis because of a low level of cell surface Fas. PMID:25225287

CRHR2/Ucn2 signaling is a novel regulator of miR-7/YY1/Fas circuitry contributing to reversal of colorectal cancer cell resistance to Fas-mediated apoptosis.

PubMed

Pothoulakis, Charalabos; Torre-Rojas, Monica; Duran-Padilla, Marco A; Gevorkian, Jonathan; Zoras, Odysseas; Chrysos, Emmanuel; Chalkiadakis, George; Baritaki, Stavroula

2018-01-15

Colorectal cancer (CRC) responds poorly to immuno-mediated cytotoxicity. Underexpression of corticotropin-releasing-hormone-receptor-2 (CRHR2) in CRC, promotes tumor survival, growth and Epithelial to Mesenchymal Transition (EMT), in vitro and in vivo. We explored the role of CRHR2 downregulation in CRC cell resistance to Fas/FasL-mediated apoptosis and the underlying molecular mechanism. CRC cell sensitivity to CH11-induced apoptosis was compared between Urocortin-2 (Ucn2)-stimulated parental and CRHR2-overexpressing CRC cell lines and targets of CRHR2/Ucn2 signaling were identified through in vitro and ex vivo analyses. Induced CRHR2/Ucn2 signaling in SW620 and DLD1 cells increased specifically their sensitivity to CH11-mediated apoptosis, via Fas mRNA and protein upregulation. CRC compared to control tissues had reduced Fas expression that was associated with lost CRHR2 mRNA, poor tumor differentiation and high risk for distant metastasis. YY1 silencing increased Fas promoter activity in SW620 and re-sensitized them to CH11-apoptosis, thus suggesting YY1 as a putative transcriptional repressor of Fas in CRC. An inverse correlation between Fas and YY1 expression was confirmed in CRC tissue arrays, while elevated YY1 mRNA was clinically relevant with advanced CRC grade and higher risk for distant metastasis. CRHR2/Ucn2 signaling downregulated specifically YY1 expression through miR-7 elevation, while miR-7 modulation in miR-7 high SW620-CRHR2+ and miR-7 low HCT116 cells, had opposite effects on YY1 and Fas expressions and cell sensitivity to CH11-killing. CRHR2/Ucn2 signaling is a negative regulator of CRC cell resistance to Fas/FasL-apoptosis via targeting the miR-7/YY1/Fas circuitry. CRHR2 restoration might prove effective in managing CRC response to immune-mediated apoptotic stimuli. © 2017 UICC.

Anti-Fas antibody-induced apoptosis and its signal transduction in human gastric carcinoma cell lines.

PubMed

Adachi, Keiko; Osaki, Mitsuhiko; Kase, Satoru; Takeda, Ami; Ito, Hisao

2003-09-01

The Fas-Fas ligand system is one of the factors involved in cell death signaling. Aberrations in the signaling pathways leading to Fas-mediated apoptosis in tumor cells have been reported in a variety of human malignant tumors. However, the Fas-mediated apoptotic pathway has not been sufficiently elucidated in human gastric carcinomas. We examined the apoptotic pathway induced by anti-Fas antibody using seven human gastric carcinoma cell lines. Apoptosis was induced in a delayed fashion and the apoptotic indices (AI) after 48 h were approximately 30-40% in MKN-45 and KATO-III cells, which both showed cleavage of the Bid protein and release of Cytochrome c from the mitochondria. Our data also demonstrated no significant relationship between the expressions of various apoptosis-related proteins and the sensitivity or resistance to anti-Fas antibody-induced apoptosis, as far as we examined. Furthermore, the apoptosis signal was inhibited by treatment with Caspase-9 and -3 inhibitors in MKN-45 and KATO-III. These findings suggest that anti-Fas antibody induced apoptosis through the type II signaling pathway in the human gastric carcinoma cell lines, MKN-45 and KATO-III.

Circulating levels of FAS/APO-1 in patients with the systemic inflammatory response syndrome.

PubMed

Torre, Donato; Tambini, Roberto; Manfredi, Mariangela; Mangani, Valerio; Livi, Paola; Maldifassi, Viviana; Campi, Paolo; Speranza, Filippo

2003-04-01

Resolution of inflammation/infection involves removal of neutrophils and other inflammatory cells by the induction of apoptosis. Fas/Apo-1 is a widely occurring apoptotic signal receptor molecule expressed by almost any type of cell, which is also released in a soluble circulating form. In this study we investigated the role of circulating Fas/Apo-1 in patients with systemic inflammatory response syndrome (SIRS). We evaluated 57 critically ill patients, 34 with infectious SIRS (sepsis and septic shock), and 23 patients with noninfectious SIRS. Circulating Fas/Apo-1 was determined by a commercially available immunoassay. Our results clearly show that levels of Fas/Apo-1 were significantly elevated in patients with infectious and noninfectious SIRS (10.4 +/- 8.1 pg/mL, controls: 5.0 +/- 0.7 pg/mL; p < 0.0001). In addition, Fas/Apo-1 levels were not able in predicting in predicting poor outcome of patients with SIRS. In conclusion, these results show that increased levels of Fas/Apo-1 from patients with SIRS is a mechanism which contribute to inflammatory response through accumulation of neutrophils at sites of inflammation/infection.

D4F alleviates macrophage-derived foam cell apoptosis by inhibiting the NF-κB-dependent Fas/FasL pathway.

PubMed

Tian, Hua; Yao, Shu-Tong; Yang, Na-Na; Ren, Jie; Jiao, Peng; Zhang, Xiangjian; Li, Dong-Xuan; Zhang, Gong-An; Xia, Zhen-Fang; Qin, Shu-Cun

2017-08-04

This study was designed to explore the protective effect of D4F, an apolipoprotein A-I mimetic peptide, on nuclear factor-κB (NF-κB)-dependent Fas/Fas ligand (FasL) pathway-mediated apoptosis in macrophages induced by oxidized low-density lipoprotein (ox-LDL). Our results showed that ox-LDL induced apoptosis, NF-κB P65 nuclear translocation and the upregulation of Fas/FasL pathway-related proteins, including Fas, FasL, Fas-associated death domain proteins (FADD), caspase-8 and caspase-3 in RAW264.7 macrophages, whereas silencing of Fas blocked ox-LDL-induced macrophage apoptosis. Furthermore, silencing of P65 attenuated macrophage apoptosis and the upregulation of Fas caused by ox-LDL, whereas P65 expression was not significantly affected by treatment with Fas siRNA. D4F attenuated the reduction of cell viability and the increase in lactate dehydrogenase leakage and apoptosis. Additionally, D4F inhibited ox-LDL-induced P65 nuclear translocation and upregulation of Fas/FasL pathway-related proteins in RAW264.7 cells and in atherosclerotic lesions of apoE -/- mice. However, Jo2, a Fas-activating monoclonal antibody, reversed the inhibitory effect of D4F on ox-LDL-induced cell apoptosis and upregulation of Fas, FasL and FADD. These data indicate that NF-κB mediates Fas/FasL pathway activation and apoptosis in macrophages induced by ox-LDL and that D4F protects macrophages from ox-LDL-induced apoptosis by suppressing the activation of NF-κB and the Fas/FasL pathway.

Fas/FasL interaction mediates imbalanced cytokine/cytotoxicity responses of iNKT cells against Jurkat cells.

PubMed

Dou, Rui; Hong, Zhenya; Tan, Xiaosheng; Hu, Fenfen; Ding, Yajie; Wang, Wei; Liang, Zhihui; Zhong, Rongrong; Wu, Xiongwen; Weng, Xiufang

2018-07-01

The rapid antitumor cytokine production and direct cytotoxicity confer invariant NKT (iNKT) cells ideal candidates for cancer therapy. However, the therapeutic potential of iNKT cells in T-cell malignant diseases remains elusive, as antigen presentation by T cells (T-T presentation) has been suggested to induce hyporesponsiveness of iNKT cells. In this study, we found discrepancies in iNKT cell responses against two T cell-origin cell lines (Jurkat and Molt-4). Human iNKT cells exhibited more intensive cytotoxicity and less efficient cytokine production in response to Fas-bearing Jurkat cells than those to the Fas-negative tumor cells (Molt-4 and myeloid-derived K562). The imbalanced cytokine/cytotoxicity responses of iNKT cells against Jurkat cells were CD1d-dependent and relied mostly on Fas/FasL interaction. The impairment in cytokine production could be overcome by Fas/FasL blocking antibodies and exogenous IL-2. Elevated CD1d levels as well as CD1d and Fas co-localization were found in T-cell lymphomas. However, defects in frequency and function of circulating iNKT cells were observed in the patients, which could be partly rescued by exogenous IL-2. Collectively, the Fas/FasL-dependent aberrant iNKT cell responses and the reversibility of the defects suggest the distinct iNKT cell manipulation in CD1d- and Fas-bearing T cell malignancies. Copyright © 2018. Published by Elsevier Ltd.

In Vivo Roles of Fatty Acid Biosynthesis Enzymes in Biosynthesis of Biotin and α-Lipoic Acid in Corynebacterium glutamicum

PubMed Central

Nagashima, Takashi; Nakamura, Eri; Kato, Ryosuke; Ohshita, Masakazu; Hayashi, Mikiro; Takeno, Seiki

2017-01-01

ABSTRACT For fatty acid biosynthesis, Corynebacterium glutamicum uses two type I fatty acid synthases (FAS-I), FasA and FasB, in addition to acetyl-coenzyme A (CoA) carboxylase (ACC) consisting of AccBC, AccD1, and AccE. The in vivo roles of the enzymes in supplying precursors for biotin and α-lipoic acid remain unclear. Here, we report genetic evidence demonstrating that the biosynthesis of these cofactors is linked to fatty acid biosynthesis through the FAS-I pathway. For this study, we used wild-type C. glutamicum and its derived biotin vitamer producer BFI-5, which was engineered to express Escherichia coli bioBF and Bacillus subtilis bioI. Disruption of either fasA or fasB in strain BFI-5 led to decreased production of biotin vitamers, whereas its amplification contributed to increased production, with a larger impact of fasA in both cases. Double disruptions of fasA and fasB resulted in no biotin vitamer production. The acc genes showed a positive effect on production when amplified simultaneously. Augmented fatty acid biosynthesis was also reflected in pimelic acid production when carbon flow was blocked at the BioF reaction. These results indicate that carbon flow down the FAS-I pathway is destined for channeling into the biotin biosynthesis pathway, and that FasA in particular has a significant impact on precursor supply. In contrast, fasB disruption resulted in auxotrophy for lipoic acid or its precursor octanoic acid in both wild-type and BFI-5 strains. The phenotypes were fully complemented by plasmid-mediated expression of fasB but not fasA. These results reveal that FasB plays a specific physiological role in lipoic acid biosynthesis in C. glutamicum. IMPORTANCE For the de novo biosynthesis of fatty acids, C. glutamicum exceptionally uses a eukaryotic multifunctional type I fatty acid synthase (FAS-I) system comprising FasA and FasB, in contrast to most bacteria, such as E. coli and B. subtilis, which use an individual nonaggregating type II fatty

Quantitative assessment of the relationship between Fas/FasL genes polymorphisms and head and neck cancer risk.

PubMed

Zhang, Dan-Feng; Jiang, Guang-Bin; Qin, Chuan-Qi; Liu, De-Xi; Hu, Ya-Jun; Zhou, Juan; Niu, Yu-Ming

2018-02-01

Molecular epidemiological studies have demonstrated a closer association between Fas/FasL polymorphisms and head and neck cancer (HNC) risk, and the results of these published studies were inconsistent. We therefore performed this meta-analysis to explore the associations between Fas/FasL polymorphisms and HNC risk. Four online databases (PubMed, Embase, CNKI, and Wanfang) were searched. Odds ratios (ORs) with 95% confidence interval (95% CIs) were calculated to assess the association between Fas -670A>G, Fas -1377G>A, and FasL -844C>T polymorphisms and HNC risk. In addition, heterogeneity, accumulative/sensitivity analysis, and publication bias were conducted to check the statistical power. Overall, 9 related publications (20 independent case-control studies) involving 3179 patients and 4217 controls were identified. Significant association of protective effects was observed between FasL -844C>T polymorphism and HNC risk in codominant and dominant model models (CT vs CC: OR = 0.89, 95% CI = 0.79-1.00, P = .05, I = 38.3%, CT+TT vs CC: OR = 0.88, 95% CI = 0.79-0.98, P = .02, I = 35.8%). Furthermore, the similar protective effects were observed the subgroup analysis of in Asian population and population-based controls group. Our meta-analysis indicated that FasL -844C>T polymorphism plays a protective role against HNC development, but the Fas -670A>G and Fas -1377G>A polymorphisms maybe not associated with HNC risk.

Quantitative assessment of the relationship between Fas/FasL genes polymorphisms and head and neck cancer risk

PubMed Central

Zhang, Dan-Feng; Jiang, Guang-Bin; Qin, Chuan-Qi; Liu, De-Xi; Hu, Ya-Jun; Zhou, Juan; Niu, Yu-Ming

2018-01-01

Abstract Background: Molecular epidemiological studies have demonstrated a closer association between Fas/FasL polymorphisms and head and neck cancer (HNC) risk, and the results of these published studies were inconsistent. We therefore performed this meta-analysis to explore the associations between Fas/FasL polymorphisms and HNC risk. Methods: Four online databases (PubMed, Embase, CNKI, and Wanfang) were searched. Odds ratios (ORs) with 95% confidence interval (95% CIs) were calculated to assess the association between Fas -670A>G, Fas -1377G>A, and FasL -844C>T polymorphisms and HNC risk. In addition, heterogeneity, accumulative/sensitivity analysis, and publication bias were conducted to check the statistical power. Results: Overall, 9 related publications (20 independent case–control studies) involving 3179 patients and 4217 controls were identified. Significant association of protective effects was observed between FasL -844C>T polymorphism and HNC risk in codominant and dominant model models (CT vs CC: OR = 0.89, 95% CI = 0.79–1.00, P = .05, I2 = 38.3%, CT+TT vs CC: OR = 0.88, 95% CI = 0.79–0.98, P = .02, I2 = 35.8%). Furthermore, the similar protective effects were observed the subgroup analysis of in Asian population and population-based controls group. Conclusion: Our meta-analysis indicated that FasL -844C>T polymorphism plays a protective role against HNC development, but the Fas -670A>G and Fas -1377G>A polymorphisms maybe not associated with HNC risk. PMID:29419701

In Vivo Roles of Fatty Acid Biosynthesis Enzymes in Biosynthesis of Biotin and α-Lipoic Acid in Corynebacterium glutamicum.

PubMed

Ikeda, Masato; Nagashima, Takashi; Nakamura, Eri; Kato, Ryosuke; Ohshita, Masakazu; Hayashi, Mikiro; Takeno, Seiki

2017-10-01

For fatty acid biosynthesis, Corynebacterium glutamicum uses two type I fatty acid synthases (FAS-I), FasA and FasB, in addition to acetyl-coenzyme A (CoA) carboxylase (ACC) consisting of AccBC, AccD1, and AccE. The in vivo roles of the enzymes in supplying precursors for biotin and α-lipoic acid remain unclear. Here, we report genetic evidence demonstrating that the biosynthesis of these cofactors is linked to fatty acid biosynthesis through the FAS-I pathway. For this study, we used wild-type C. glutamicum and its derived biotin vitamer producer BFI-5, which was engineered to express Escherichia coli bioBF and Bacillus subtilis bioI Disruption of either fasA or fasB in strain BFI-5 led to decreased production of biotin vitamers, whereas its amplification contributed to increased production, with a larger impact of fasA in both cases. Double disruptions of fasA and fasB resulted in no biotin vitamer production. The acc genes showed a positive effect on production when amplified simultaneously. Augmented fatty acid biosynthesis was also reflected in pimelic acid production when carbon flow was blocked at the BioF reaction. These results indicate that carbon flow down the FAS-I pathway is destined for channeling into the biotin biosynthesis pathway, and that FasA in particular has a significant impact on precursor supply. In contrast, fasB disruption resulted in auxotrophy for lipoic acid or its precursor octanoic acid in both wild-type and BFI-5 strains. The phenotypes were fully complemented by plasmid-mediated expression of fasB but not fasA These results reveal that FasB plays a specific physiological role in lipoic acid biosynthesis in C. glutamicum IMPORTANCE For the de novo biosynthesis of fatty acids, C. glutamicum exceptionally uses a eukaryotic multifunctional type I fatty acid synthase (FAS-I) system comprising FasA and FasB, in contrast to most bacteria, such as E. coli and B. subtilis , which use an individual nonaggregating type II fatty acid synthase

Sunlight triggers cutaneous lupus through a CSF-1-dependent mechanism in MRL-Fas(lpr) mice.

PubMed

Menke, Julia; Hsu, Mei-Yu; Byrne, Katelyn T; Lucas, Julie A; Rabacal, Whitney A; Croker, Byron P; Zong, Xiao-Hua; Stanley, E Richard; Kelley, Vicki R

2008-11-15

Sunlight (UVB) triggers cutaneous lupus erythematosus (CLE) and systemic lupus through an unknown mechanism. We tested the hypothesis that UVB triggers CLE through a CSF-1-dependent, macrophage (Mø)-mediated mechanism in MRL-Fas(lpr) mice. By constructing mutant MRL-Fas(lpr) strains expressing varying levels of CSF-1 (high, intermediate, none), and use of an ex vivo gene transfer to deliver CSF-1 intradermally, we determined that CSF-1 induces CLE in lupus-susceptible MRL-Fas(lpr) mice, but not in lupus-resistant BALB/c mice. UVB incites an increase in Møs, apoptosis in the skin, and CLE in MRL-Fas(lpr), but not in CSF-1-deficient MRL-Fas(lpr) mice. Furthermore, UVB did not induce CLE in BALB/c mice. Probing further, UVB stimulates CSF-1 expression by keratinocytes leading to recruitment and activation of Møs that, in turn, release mediators, which induce apoptosis in keratinocytes. Thus, sunlight triggers a CSF-1-dependent, Mø-mediated destructive inflammation in the skin leading to CLE in lupus-susceptible MRL-Fas(lpr) but not lupus-resistant BALB/c mice. Taken together, CSF-1 is envisioned as the match and lupus susceptibility as the tinder leading to CLE.

Matrix metalloproteinases and soluble Fas/FasL system as novel regulators of apoptosis in children and young adults on chronic dialysis.

PubMed

Musiał, Kinga; Zwolińska, Danuta

2011-07-01

The system of membrane receptor Fas and its ligand FasL compose one of the main pathways triggering apoptosis. However, the role of their soluble forms has not been clarified yet. Although sFasL can be converted from the membrane-bound form by matrix metalloproteinases (MMPs), there are no data on relations between sFas/sFasL, MMPs and their tissue inhibitors (TIMPs) in patients on chronic dialysis--neither children nor adults. The aim of our study was to evaluate serum concentrations of sFas, sFasL, and their potential regulators (MMP-2, MMP-7, MMP-9, TIMP-1, TIMP-2), in children and young adults chronically dialyzed. Twenty-two children on automated peritoneal dialysis (APD), 19 patients on hemodialysis (HD) and 30 controls were examined. Serum concentrations of sFas, sFasL, MMPs and TIMPs were assessed by ELISA. Median values of sFas, sFasL, sFas/sFasL ratio, MMP-2, MMP-7, MMP-9, TIMP-1 and TIMP-2 were significantly elevated in all dialyzed patients vs. controls, the highest values being observed in subjects on HD. A single HD session caused the decrease in values of all parameters to the levels below those seen in children on APD. Regression analysis revealed that MMP-7 and TIMP-1 were the best predictors of sFas and sFasL concentrations. Children and young adults on chronic dialysis are prone to sFas/sFasL system dysfunction, more pronounced in patients on hemodialysis. The correlations between sFas/sFasL and examined enzymes suggest that MMPs and TIMPs take part in the regulation of cell death in the pediatric population on chronic dialysis, triggering both anti- (sFas) and pro-apoptotic (sFasL) mechanisms.

Intratracheal Administration of Small Interfering RNA Targeting Fas Reduces Lung Ischemia-Reperfusion Injury.

PubMed

Del Sorbo, Lorenzo; Costamagna, Andrea; Muraca, Giuseppe; Rotondo, Giuseppe; Civiletti, Federica; Vizio, Barbara; Bosco, Ornella; Martin Conte, Erica L; Frati, Giacomo; Delsedime, Luisa; Lupia, Enrico; Fanelli, Vito; Ranieri, V Marco

2016-08-01

Lung ischemia-reperfusion injury is the main cause of primary graft dysfunction after lung transplantation and results in increased morbidity and mortality. Fas-mediated apoptosis is one of the pathologic mechanisms involved in the development of ischemia-reperfusion injury. We hypothesized that the inhibition of Fas gene expression in lungs by intratracheal administration of small interfering RNA could reduce lung ischemia-reperfusion injury in an ex vivo model reproducing the procedural sequence of lung transplantation. Prospective, randomized, controlled experimental study. University research laboratory. C57/BL6 mice weighing 28-30 g. Ischemia-reperfusion injury was induced in lungs isolated from mice, 48 hours after treatment with intratracheal small interfering RNA targeting Fas, control small interfering RNA, or vehicle. Isolated lungs were exposed to 6 hours of cold ischemia (4°C), followed by 2 hours of warm (37°C) reperfusion with a solution containing 10% of fresh whole blood and mechanical ventilation with constant low driving pressure. Fas gene expression was significantly silenced at the level of messenger RNA and protein after ischemia-reperfusion in lungs treated with small interfering RNA targeting Fas compared with lungs treated with control small interfering RNA or vehicle. Silencing of Fas gene expression resulted in reduced edema formation (bronchoalveolar lavage protein concentration and lung histology) and improvement in lung compliance. These effects were associated with a significant reduction of pulmonary cell apoptosis of lungs treated with small interfering RNA targeting Fas, which did not affect cytokine release and neutrophil infiltration. Fas expression silencing in the lung by small interfering RNA is effective against ischemia-reperfusion injury. This approach represents a potential innovative strategy of organ preservation before lung transplantation.

Interferon-gamma induces apoptosis and augments the expression of Fas and Fas ligand by microglia in vitro.

PubMed

Badie, B; Schartner, J; Vorpahl, J; Preston, K

2000-04-01

Activation of microglia by interferon-gamma (IFN-gamma) has been implicated in a number of central nervous system (CNS) inflammatory disease processes. Because IFN-gamma has also been shown to play a role in programmed cell death, we investigated its cytotoxicity and its effect on the Fas apoptotic pathway in microglia. Flow cytometry was used to quantify the IFN-gamma-mediated apoptotic response and Fas and Fas ligand (FasL) expression in two well-characterized murine microglia cell lines (BV-2 and N9). Nuclear fragmentation, suggestive of apoptosis, was noted within 24 h of incubation of microglia with IFN-gamma (10 U/ml). After a 72-h incubation, almost every BV-2 and N9 microglia, but not GL261 glioma cells, underwent cell death and detached from the culture plates. This cytotoxicity occurred even at low IFN-gamma concentrations (1 U/ml) and was inhibited by BAF, a pan-caspase inhibitor. Incubation of BV-2 and N9 microglia, but not GL261 glioma cells, with IFN-gamma also potentiated the expression of Fas and FasL in a similar dose-response and time-course manner, as seen for the apoptotic response. Whereas Fas expression increased by 100% in both microglia cells, FasL upregulation was more pronounced and increased by as much as 200% in the N9 cells. These findings suggest that in addition to its role as a microglia activator, IFN-gamma may also induce apoptosis of microglia, possibly through simultaneous upregulation of Fas and FasL. Interferon-gamma modulation of the Fas pathway and apoptosis in microglia may be important in the pathogenesis of inflammatory CNS disease processes. Copyright 2000 Academic Press.

Expression of Fas and Fas-ligand in donor hematopoietic stem and progenitor cells is dissociated from the sensitivity to apoptosis.

PubMed

Pearl-Yafe, Michal; Yolcu, Esma S; Stein, Jerry; Kaplan, Ofer; Shirwan, Haval; Yaniv, Isaac; Askenasy, Nadir

2007-10-01

The interaction between the Fas receptor and its cognate ligand (FasL) has been implicated in the mutual suppression of donor and host hematopoietic cells after transplantation. Following the observation of deficient early engraftment of Fas and FasL-defective donor cells and recipients, we determined the role of the Fas-FasL interaction. Donor cells were recovered after syngeneic (CD45.1-->CD45.2) transplants from various organs and assessed for expression of Fas/FasL in reference to lineage markers, carboxyfluorescein succinimidyl ester dilution, Sca-1 and c-kit expression. Naïve and bone marrow-homed cells were challenged for apoptosis ex vivo. The Fas receptor and ligand were markedly upregulated to 40% to 60% (p < 0.001 vs 5-10% in naïve cells) within 2 days after syngeneic transplantation, while residual host cells displayed modest and delayed upregulation of these molecules ( approximately 10%). All lin(-)Sca(+)c-kit(+) cells were Fas(+)FasL(+), including 95% of Sca-1(+) and 30% of c-kit(+) cells. Fas and FasL expression varied in donor cells that homed to bone marrow, spleen, liver and lung, and was induced by interaction with the stroma, irradiation, cell cycling, and differentiation. Bone marrow-homed donor cells challenged with supralethal doses of FasL were insensitive to apoptosis (3.2% +/- 1% vs 38% +/- 5% in naïve bone marrow cells), and engraftment was not affected by pretransplantation exposure of donor cells to an apoptotic challenge with FasL. There was no evidence of Fas-mediated suppression of donor and host cell activity after transplantation. Resistance to Fas-mediated apoptosis evolves as a functional characteristic of hematopoietic reconstituting stem and progenitor cells, providing them competitive engraftment advantage over committed progenitors.

Induction of Fas receptor and Fas ligand by nodularin is mediated by NF-{kappa}B in HepG2 cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Feng Gong, E-mail: gong-feng@northwestern.edu; Anong Biotech Institute, Tianjin; Li Ying

Nodularin is a natural toxin with multiple features, including inhibitor of protein phosphatases 1 and 2A as well as tumor initiator and promoter. One unique feature of nodularin is that this chemical is a hepatotoxin. It can accumulate into the liver after contact and lead to severe damage to hepatocyte, such as apoptosis. Fas receptor (Fas) and Fas ligand (FasL) system is a critical signaling network triggering apoptosis. In current study, we investigated whether nodularin can induce Fas and FasL expression in HepG2 cell, a well used in vitro model for the study of human hepatocytes. Our data showed nodularinmore » induced Fas and FasL expression, at both mRNA and protein level, in a time- and dose-dependent manner. We also found nodularin induced apoptosis at the concentration and incubation time that Fas and FasL were significantly induced. Neutralizing antibody to FasL reduced nodularin-induced apoptosis. Further studies demonstrated that nodularin promoted nuclear translocation and activation of p65 subunit of NF-{kappa}B. By applying siRNA targeting p65, which knocked down p65 in HepG2 cells, we successfully impaired the activation of NF-{kappa}B by nodularin. In these p65 knockdown cells, we observed that Fas and FasL expression and apoptosis induced by nodularin were significantly reduced. These findings suggest the induction of Fas and FasL expression and thus cell apoptosis in HepG2 cells by nodularin is mediated through NF-{kappa}B pathway.« less

The Btk-dependent PIP5K1γ lipid kinase activation by Fas counteracts FasL-induced cell death.

PubMed

Rossin, Aurélie; Lounnas, Nadia; Durivault, Jérôme; Miloro, Giorgia; Gagnoux-Palacios, Laurent; Hueber, Anne-Odile

2017-11-01

The Fas/FasL system plays a critical role in death by apoptosis and immune escape of cancer cells. The Fas receptor being ubiquitously expressed in tissues, its apoptotic-inducing function, initiated upon FasL binding, is tightly regulated by several negative regulatory mechanisms to prevent inappropriate cell death. One of them, involving the non-receptor tyrosine kinase Btk, was reported mainly in B cells and only poorly described. We report here that Btk negatively regulates, through its tyrosine kinase activity, the FasL-mediated cell death in epithelial cell lines from colon cancer origin. More importantly, we show that Btk interacts not only with Fas but also with the phosphatidylinositol-4-phosphate 5-kinase, PIP5K1γ, which, upon stimulation by Fas ligand, is responsible of a rapid and transient synthesis of phosphatidylinositol-4,5-bisphosphate (PI(4,5)P 2 ). This production requires both the presence and the tyrosine kinase activity of Btk, and participates in the negative regulation of FasL-mediated cell death since knocking down PIP5K1γ expression significantly strengthens the apoptotic signal upon FasL engagement. Altogether, our data demonstrate the cooperative role of Btk and PIP5K1γ in a FasL-induced PI(4,5)P 2 production, both proteins participating to the threshold setting of FasL-induced apoptotic commitment in colorectal cell lines.

The role of the Fas/FasL signaling pathway in environmental toxicant-induced testicular cell apoptosis: An update.

PubMed

Wang, Mei; Su, Ping

2018-04-01

The Fas/FasL signaling pathway is one of the major pathways that regulate apoptosis. Increasing studies have shown that the activation of the Fas/FasL signaling pathway is closely associated with testicular cell apoptosis. However, the mechanism involved is still unclear. We discuss recent findings regarding the molecular mechanisms by which environmental toxicants induce testicular pathology via Fas/FasL signaling. These findings suggest that Fas/FasL signaling is employed to impact the sensitivity (a response to external factors) of germ cells, disrupt steroidogenic hormone and cytokine metabolism mediated by Sertoli cells, and elicit the activation of NFAT (nuclear factor of activated T-cells) in Leydig cell apoptosis. Consequently, degeneration of testicular somatic (Sertoli and Leydig) and spermatogenic cells, leads to decreased numbers of mature sperm and subsequently translates into infertility issues. Collectively, these findings illustrate that it is beneficial to develop potential targets for a new generation of new pharmaceutical therapies that would alleviate testicular dysfunctions. BTB: blood-testis barrier; DD: death domains; DR3: death receptor 3; DR4: death receptor 4; DR5: death receptor 5; DED: death effector domain; DISC: death-inducing signaling complex; ERα: estrogen receptor alpha; FADD: Fas-associated death domain; FSH: follicle- stimulating hormone; IL-1β: interleukin 1 beta; LH: luteinizing hormone; LPS: lipopolysaccharide; mFas: membrane Fas; MMP2: matrix metalloproteinase-2; MTA1: metastasis-associated protein 1; NAC: N-acetylcysteine; NCCD: the Nomenclature Committee on Cell Death; NFAT: nuclear factor of activated T-cells; NF-kB: nuclear transcription factor-kappaB; NO: nitric oxide; NP: 4-nonylphenol; PCD: programmed cell death; PP1/PP2A: protein phosphatase 1 and 2A; ROS: reactive oxygen species; sFas: soluble Fas; T: testosterone; TGF-β: transforming growth factor-beta; THD: TNF homology domain; TIMP-2: tissue inhibitor of

A role for the Fas/FasL system in modulating genetic susceptibility to T-cell lymphoblastic lymphomas.

PubMed

Villa-Morales, María; Santos, Javier; Pérez-Gómez, Eduardo; Quintanilla, Miguel; Fernández-Piqueras, José

2007-06-01

The Fas/FasL system mediates induced apoptosis of immature thymocytes and peripheral T lymphocytes, but little is known about its implication in genetic susceptibility to T-cell malignancies. In this article, we report that the expression of FasL increases early in all mice after gamma-radiation treatments, maintaining such high levels for a long time in mice that resisted tumor induction. However, its expression is practically absent in T-cell lymphoblastic lymphomas. Interestingly, there exist significant differences in the level of expression between two mice strains exhibiting extremely distinct susceptibilities that can be attributed to promoter functional polymorphisms. In addition, several functional nucleotide changes in the coding sequences of both Fas and FasL genes significantly affect their biological activity. These results lead us to propose that germ-line functional polymorphisms affecting either the levels of expression or the biological activity of both Fas and FasL genes could be contributing to the genetic risk to develop T-cell lymphoblastic lymphomas and support the use of radiotherapy as an adequate procedure to choose in the treatment of T-cell malignancies.

FAS system deregulation in T-cell lymphoblastic lymphoma

PubMed Central

Villa-Morales, M; Cobos, M A; González-Gugel, E; Álvarez-Iglesias, V; Martínez, B; Piris, M A; Carracedo, A; Benítez, J; Fernández-Piqueras, J

2014-01-01

The acquisition of resistance towards FAS-mediated apoptosis may be required for tumor formation. Tumors from various histological origins exhibit FAS mutations, the most frequent being hematological malignancies. However, data regarding FAS mutations or FAS signaling alterations are still lacking in precursor T-cell lymphoblastic lymphomas (T-LBLs). The available data on acute lymphoblastic leukemia, of precursor origin as well, indicate a low frequency of FAS mutations but often report a serious reduction in FAS-mediated apoptosis as well as chemoresistance, thus suggesting the occurrence of mechanisms able to deregulate the FAS signaling pathway, different from FAS mutation. Our aim at this study was to determine whether FAS-mediated apoptotic signaling is compromised in human T-LBL samples and the mechanisms involved. This study on 26 T-LBL samples confirms that the FAS system is impaired to a wide extent in these tumors, with 57.7% of the cases presenting any alteration of the pathway. A variety of mechanisms seems to be involved in such alteration, in order of frequency the downregulation of FAS, the deregulation of other members of the pathway and the occurrence of mutations at FAS. Considering these results together, it seems plausible to think of a cumulative effect of several alterations in each T-LBL, which in turn may result in FAS/FASLG system deregulation. Since defective FAS signaling may render the T-LBL tumor cells resistant to apoptotic cell death, the correct prognosis, diagnosis and thus the success of anticancer therapy may require such an in-depth knowledge of the complete scenario of FAS-signaling alterations. PMID:24603338

Corticotrophin-releasing hormone and corticosterone impair development of preimplantation embryos by inducing oviductal cell apoptosis via activating the Fas system: an in vitro study.

PubMed

Tan, Xiu-Wen; Ji, Chang-Li; Zheng, Liang-Liang; Zhang, Jie; Yuan, Hong-Jie; Gong, Shuai; Zhu, Jiang; Tan, Jing-He

2017-08-01

What are the mechanisms by which corticotrophin-releasing hormone (CRH) and corticosterone impair the development of preimplantation embryos in the oviduct. CRH and corticosterone do not affect preimplantation embryos directly, but impair their development indirectly by triggering apoptosis of oviductal epithelial cells (OECs) through activation of the Fas system. Studies report that stress impairs embryo development with facilitated secretion of CRH and glucocorticoids. Although an in vivo study demonstrated that preimplantation stress impaired embryo development in conjunction with oviductal apoptosis and activation of the Fas system, whether CRH or glucocorticoids damage embryos directly or indirectly by way of oviductal cells remains to be clarified. Mice of Kunming strain, the generalized lymphoproliferative disorder (gld) mice with a germline mutation F273L in Fas ligand in a C57BL/6J genomic background and the wild-type C57BL/6J mice were used. Female mice were used 8-10 weeks after birth. While some female mice were killed 48 h after being injected with equine CG to collect oviducts and prepare OECs, others were killed to recover zygotes after mating with males following superovulation with eCG and hCG. The zygotes obtained were cultured with or without CRH or corticosterone (CRH/Cort) either in Chatot-Ziomek-Bavister (CZB) medium with or without OECs or in conditioned medium (CM) conditioned with OECs pretreated or not with CRH/Cort. Preimplantation development, levels of redox potential and apoptosis, and expression of CRH receptor 1 (CRHR1), glucocorticoid receptor (GR), Fas and 11β-hydroxysteroid dehydrogenase (HSD) were observed in embryos recovered at different times of in vitro culture. After culture of OECs with or without CRH/Cort, levels of redox potential and apoptosis, mRNA and protein expression of growth factors, and protein expression of CRHR1, GR and Fas were examined in OECs and the level of FasL was measured in CM. The gld mice were used

Overexpression of soluble Fas ligand following AAV gene therapy prevents retinal ganglion cell death in chronic and acute murine models of glaucoma

PubMed Central

Krishnan, Anitha; Fei, Fei; Jones, Alexander; Busto, Patricia; Marshak-Rothstein, Ann; Ksander, Bruce R.; Gregory-Ksander, Meredith

2016-01-01

Glaucoma is a multifactorial disease resulting in the death of retinal ganglion cells (RGCs) and irreversible blindness. Glaucoma-associated RGC cell death depends on the pro-apoptotic and proinflammatory activity of membrane-bound FasL (mFasL). In contrast to mFasL, the natural soluble FasL cleavage product (sFasL) inhibits mFasL-mediated apoptosis and inflammation and is therefore a mFasL antagonist. DBA/2J (D2) mice spontaneously develop glaucoma and predictably RGC destruction is exacerbated by expression of a mutated membrane-only FasL (mFasL) gene that lacks the extracellular cleavage site. Remarkably, one time intraocular adeno-associated virus-mediated gene delivery of sFasL (AAV2.sFasL) provides complete and sustained neuroprotection in both the chronic D2 and acute microbead-induced models of glaucoma, even in the presence of elevated intraocular pressure (IOP). This protection correlated with inhibition of glial activation, reduced production of TNFα, and decreased apoptosis of RGCs and loss of axons. These data indicate that cleavage of FasL under homeostatic conditions, and the ensuing release of sFasL, normally limits the neurodestructive activity of FasL. The data further support the notion that sFasL, and not mFasL, contributes to the immune privileged status of the eye. PMID:27849168

Increased FasL expression correlates with apoptotic changes in granulocytes cultured with oxidized clozapine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Husain, Zaheed; Department of Pathology, Harvard Medical School, Boston, MA; Almeciga, Ingrid

Clozapine has been associated with a 1% incidence of agranulocytosis. The formation of an oxidized intermediate clozapine metabolite has been implicated in direct polymorphonuclear (PMN) toxicity. We utilized two separate systems to analyze the role of oxidized clozapine in inducing apoptosis in treated cells. Human PMN cells incubated with clozapine (0-10 {mu}M) in the presence of 0.1 mM H{sub 2}O{sub 2} demonstrated a progressive decrease of surface CD16 expression along with increased apoptosis. RT-PCR analysis showed decreased CD16 but increased FasL gene expression in clozapine-treated PMN cells. No change in constitutive Fas expression was observed in treated cells. In HL-60more » cells induced to differentiate with retinoic acid (RA), a similar increase in FasL expression, but no associated changes in CD16 gene expression, was observed following clozapine treatments. Our results demonstrate increased FasL gene expression in oxidized clozapine-induced apoptotic neutrophils suggesting that apoptosis in granulocytes treated with clozapine involves Fas/FasL interaction that initiates a cascade of events leading to clozapine-induced agranulocytosis.« less

Switch from type II to I Fas/CD95 death signaling on in vitro culturing of primary hepatocytes.

PubMed

Walter, Dorothée; Schmich, Kathrin; Vogel, Sandra; Pick, Robert; Kaufmann, Thomas; Hochmuth, Florian Christoph; Haber, Angelika; Neubert, Karin; McNelly, Sabine; von Weizsäcker, Fritz; Merfort, Irmgard; Maurer, Ulrich; Strasser, Andreas; Borner, Christoph

2008-12-01

Fas/CD95-induced apoptosis of hepatocytes in vivo proceeds through the so-called type II pathway, requiring the proapoptotic BH3-only Bcl-2 family member Bid for mitochondrial death signaling. Consequently, Bid-deficient mice are protected from anti-Fas antibody injection induced fatal hepatitis. We report the unexpected finding that freshly isolated mouse hepatocytes, cultured on collagen or Matrigel, become independent of Bid for Fas-induced apoptosis, thereby switching death signaling from type II to type I. In such in vitro cultures, Fas ligand (FasL) activates caspase-3 without Bid cleavage, Bax/Bak activation or cytochrome c release, and neither Bid ablation nor Bcl-2 overexpression is protective. The type II to type I switch depends on extracellular matrix adhesion, as primary hepatocytes in suspension die in a Bid-dependent manner. Moreover, the switch is specific for FasL-induced apoptosis as collagen-plated Bid-deficient hepatocytes are protected from tumor necrosis factor alpha/actinomycin D (TNFalpha/ActD)-induced apoptosis. Our data suggest a selective crosstalk between extracellular matrix and Fas-mediated signaling that favors mitochondria-independent type I apoptosis induction.

Targeted metabolomics analysis reveals the association between maternal folic acid supplementation and fatty acids and amino acids profiles in rat pups.

PubMed

Liu, Zhipeng; Liu, Rui; Chou, Jing; Yu, Jiaying; Liu, Xiaowei; Sun, Changhao; Li, Ying; Liu, Liyan

2018-07-15

Maternal diet during pregnancy can influence offspring's health by affecting development and metabolism. This study aimed to analyze the influence of maternal folic acid (FA) supplementation on the metabolism of rat pups using targeted metabolomics. Twenty female rats were randomly assigned to a FA supplementation (FAS group, n = 10) or control group (n = 10), which were fed AIN93G diet with 2 or 10 mg/kg FA, respectively. We then measured amino acids and their derivatives, biogenic amines, and fatty acids in the female rats and their pups by ultra-high performance liquid chromatography-triple quadrupole mass spectrometry (UHPLC/MS-MS) and gas chromatography-mass spectrometry (GC/MS-MS). In maternal rats, the significant changes of three metabolites (proline, γ-aminobutyric acid and esterified octadecatetraenoic acid, P < 0.05) were observed in FAS group. For the rat pups, FAS pups had significantly lower homocysteine and higher FA levels than control pups. The lower levels of amino acids (leucine, isoleucine, serine, proline) were obtained in FAS pups. Furthermore, there were the decreased esterified fatty acids (arachidonic acid, eicosapentaenoic acid, and docosatetraenoic acid) and free fatty acids (oleic acid, linoleic acid, γ-linolenic acid, octadecatetraenoic acid, arachidonic acid, eicosapentaenoic acid and selacholeic acid) in FAS pups. Metabolic changes in the FAS pups were characterized by changes in fatty acids and amino acids. These results suggested that FA supplementation during pregnancy influenced amino acids and fatty acids metabolism in rat pups. This study provides new insights into the regulation of amino acids and fatty acids metabolism during early life. Copyright © 2018 Elsevier B.V. All rights reserved.

Switch from type II to I Fas/CD95 death signaling upon in vitro culturing of primary hepatocytes

PubMed Central

Walter, Dorothée; Schmich, Kathrin; Vogel, Sandra; Pick, Robert; Kaufmann, Thomas; Hochmuth, Florian Christoph; Haber, Angelika; Neubert, Karin; McNelly, Sabine; von Weizsäcker, Fritz; Merfort, Irmgard; Maurer, Ulrich; Strasser, Andreas; Borner, Christoph

2010-01-01

Fas/CD95-induced apoptosis of hepatocytes in vivo proceeds through the so-called type II pathway, requiring the pro-apoptotic BH3-only Bcl-2 family member Bid for mitochondrial death signaling. Consequently, Bid-deficient mice are protected from anti-Fas antibody injection induced fatal hepatitis. Here we report the unexpected finding that freshly isolated mouse hepatocytes, cultured on collagen or Matrigel™, become independent of Bid for Fas-induced apoptosis, thereby switching death signaling from type II to type I. In such in vitro cultures, FasL activates caspase-3 without Bid cleavage, Bax/Bak activation or cytochrome c release, and neither Bid ablation nor Bcl-2 overexpression is protective. The type II to type I switch depends on extracellular matrix adhesion, as primary hepatocytes in suspension die in a Bid-dependent manner. Moreover, the switch is specific for FasL-induced apoptosis as collagen-plated Bid-deficient hepatocytes are protected from TNFα/ActD-induced apoptosis. Conclusion Our data suggest a selective crosstalk between extracellular matrix and Fas-mediated signaling which favours mitochondria-independent type I apoptosis induction. PMID:19003879

The Fas/Fap-1/Cav-1 complex regulates IL-1RA secretion in mesenchymal stem cells to accelerate wound healing.

PubMed

Kou, Xiaoxing; Xu, Xingtian; Chen, Chider; Sanmillan, Maria Laura; Cai, Tao; Zhou, Yanheng; Giraudo, Claudio; Le, Anh; Shi, Songtao

2018-03-14

Mesenchymal stem cells (MSCs) are capable of secreting exosomes, extracellular vesicles, and cytokines to regulate cell and tissue homeostasis. However, it is unknown whether MSCs use a specific exocytotic fusion mechanism to secrete exosomes and cytokines. We show that Fas binds with Fas-associated phosphatase-1 (Fap-1) and caveolin-1 (Cav-1) to activate a common soluble N -ethylmaleimide-sensitive factor (NSF) attachment protein receptor (SNARE)-mediated membrane fusion mechanism to release small extracellular vesicles (sEVs) in MSCs. Moreover, we reveal that MSCs produce and secrete interleukin-1 receptor antagonist (IL-1RA) associated with sEVs to maintain rapid wound healing in the gingiva via the Fas/Fap-1/Cav-1 cascade. Tumor necrosis factor-α (TNF-α) serves as an activator to up-regulate Fas and Fap-1 expression via the nuclear factor κB pathway to promote IL-1RA release. This study identifies a previously unknown Fas/Fap-1/Cav-1 axis that regulates SNARE-mediated sEV and IL-1RA secretion in stem cells, which contributes to accelerated wound healing. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

A new version of the HBSC Family Affluence Scale - FAS III: Scottish Qualitative Findings from the International FAS Development Study.

PubMed

Hartley, Jane E K; Levin, Kate; Currie, Candace

A critical review of the Family Affluence Scale (FAS) concluded that FAS II was no longer discriminatory within very rich or very poor countries, where a very high or a very low proportion of children were categorised as high FAS or low FAS respectively (Currie et al. 2008). The review concluded that a new version of FAS - FAS III - should be developed to take into account current trends in family consumption patterns across the European region, the US and Canada. In 2012, the FAS Development and Validation Study was conducted in eight countries - Denmark, Greenland, Italy, Norway, Poland, Romania, Slovakia and Scotland. This paper describes the Scottish qualitative findings from this study. The Scottish qualitative fieldwork comprising cognitive interviews and focus groups sampled from 11, 13 and 15 year-old participants from 18 of the most- and least- economically deprived schools. These qualitative results were used to inform the final FAS III recommendations.

Fatty acid synthase as a tumor marker: its extracellular expression in human breast cancer.

PubMed

Wang, Young Y; Kuhajda, Francis P; Li, Jinong; Finch, Teia T; Cheng, Paul; Koh, Clare; Li, Tianwei; Sokoll, Lori J; Chan, Daniel W

2004-07-01

Overexpression of fatty acid synthase (FAS EC 2.3.1.85) is associated with certain cancers and therefore is a putative tumor marker. The presence of FAS in patients with breast, prostate, colon, ovarian, and other cancers has been reported. The mechanism of FAS overexpression in malignancies remains unknown. Here, we show that FAS is released into the extracellular space in cancer cells. The extracellular FAS are present in various immunoreactive forms, and show different expression patterns in various cancer cells. In serum of breast cancer patients, the FAS is a small molecule similar to the form in breast cancer cell lysate but not conditioned medium of cultured cells. The extracellular expression of FAS in breast cancer cells is time dependent and may be hormone independent. These results indicate that the FAS are an ordered cellular response of a living cell and actively exclude excess intracellular FAS molecules from the cell. This phenomenon is up-regulated in breast and may be in other cancer cells as well. Significant elevation of FAS was detected in serum of breast cancer patients compared to healthy subjects. In comparison with CA27.29, no correlation between these two tumor markers was found. Thus, the extracellular FAS may serve as a potential diagnostic and prognostic marker.

Fas/Fas ligand regulation mediates cell death in human Ewing's sarcoma cells treated with melatonin

PubMed Central

García-Santos, G; Martin, V; Rodríguez-Blanco, J; Herrera, F; Casado-Zapico, S; Sánchez-Sánchez, A M; Antolín, I; Rodríguez, C

2012-01-01

Background: Despite recent advances in cancer therapy, the 5-year survival rate for Ewing's sarcoma is still very low, and new therapeutic approaches are necessary. It was found previously that melatonin induces cell death in the Ewing's sarcoma cell line, SK-N-MC, by activating the extrinsic apoptotic pathway. Methods: Melatonin actions were analysed by metabolic viability/survival cell assays, flow cytometry, quantitative PCR for mRNA expression, western blot for protein activation/expression and electrophoretic mobility shift assay for transcription factor activation. Results: Melatonin increases the expression of Fas and its ligand Fas L, this increase being responsible for cell death induced by the indolamine. Melatonin also produces a transient increase in intracellular oxidants and activation of the redox-regulated transcription factor Nuclear factor-kappaB. Inhibition of such activation prevents cell death and Fas/Fas L upregulation. Cytotoxic effect and Fas/Fas L regulation occur in all Ewing's cell lines studied, and do not occur in the other tumour cell lines studied where melatonin does not induce cell death. Conclusion: Our data offers new insights in the study of alternative therapeutic strategies in the treatment of Ewing's sarcoma. Further attention deserves to be given to the differences in the cellular biology of sensitive tumours that could explain the cytotoxic effect of melatonin and the increase in the level of free radicals caused by this molecule, in particular cancer types. PMID:22382690

Mitochondrial free cholesterol loading sensitizes to TNF- and Fas-mediated steatohepatitis.

PubMed

Marí, Montserrat; Caballero, Francisco; Colell, Anna; Morales, Albert; Caballeria, Juan; Fernandez, Anna; Enrich, Carlos; Fernandez-Checa, José C; García-Ruiz, Carmen

2006-09-01

The etiology of progression from steatosis to steatohepatitis (SH) remains unknown. Using nutritional and genetic models of hepatic steatosis, we show that free cholesterol (FC) loading, but not free fatty acids or triglycerides, sensitizes to TNF- and Fas-induced SH. FC distribution in endoplasmic reticulum (ER) and plasma membrane did not cause ER stress or alter TNF signaling. Rather, mitochondrial FC loading accounted for the hepatocellular sensitivity to TNF due to mitochondrial glutathione (mGSH) depletion. Selective mGSH depletion in primary hepatocytes recapitulated the susceptibility to TNF and Fas seen in FC-loaded hepatocytes; its repletion rescued FC-loaded livers from TNF-mediated SH. Moreover, hepatocytes from mice lacking NPC1, a late endosomal cholesterol trafficking protein, or from obese ob/ob mice, exhibited mitochondrial FC accumulation, mGSH depletion, and susceptibility to TNF. Thus, we propose a critical role for mitochondrial FC loading in precipitating SH, by sensitizing hepatocytes to TNF and Fas through mGSH depletion.

Fas- and Mitochondria-Mediated Signaling Pathway Involved in Osteoblast Apoptosis Induced by AlCl3.

PubMed

Xu, Feibo; Ren, Limin; Song, Miao; Shao, Bing; Han, Yanfei; Cao, Zheng; Li, Yanfei

2018-07-01

Aluminum (Al) is known to induce apoptosis of osteoblasts (OBs). However, the mechanism is not yet established. To investigate the apoptotic mechanism of OBs induced by aluminum trichloride (AlCl 3 ), the primary OBs from the craniums of fetal Wistar rats were exposed to 0 mg/mL (control group, CG), 0.06 mg/mL (low-dose group, LG), 0.12 mg/mL (mid-dose group, MG), and 0.24 mg/mL (high-dose group, HG) AlCl 3 for 24 h, respectively. We observed that AlCl 3 induced OB apoptosis with the appearance of apoptotic morphology and increase of apoptosis rate. Additionally, AlCl 3 treatment activated mitochondrial-mediated signaling pathway, accompanied by mitochondrial membrane potential (ΔΨm) depolarization, release of cytochrome c from the mitochondria to the cytoplasm, as well as survival signal-related factor caspase-9 and caspase-3 activation. AlCl 3 exposure also activated Fas/Fas ligand signaling pathway, presented as Fas, Fas ligand, and Fas-associated death domain expression enhancement and caspase-8 activation, as well as the hydrolysis of Bid to truncated Bid, suggesting that the Fas-mediated signaling pathway might aggravate mitochondria-mediated OB apoptosis through hydrolyzing Bid. Furthermore, AlCl 3 exposure inhibited Bcl-2 protein expression and increased the expressions of Bax, Bak, and Bim in varying degrees. These results indicated that AlCl 3 exposure induced OB apoptosis through activating Fas- and mitochondria-mediated signaling pathway and disrupted B-cell lymphoma-2 family proteins.

Lead induces apoptosis in mouse TM3 Leydig cells through the Fas/FasL death receptor pathway.

PubMed

He, Xiuyuan; Wu, Jing; Yuan, Liyun; Lin, Feng; Yi, Jine; Li, Jing; Yuan, Hui; Shi, Jinling; Yuan, Tingting; Zhang, Shufang; Fan, Yongheng; Zhao, Zhihang

2017-12-01

The study was aimed to investigate the effect of Pb toxicity on mouse Leydig cells and its molecular mechanism. The TM3 cells were cultured in vitro and exposed to Pb at different concentrations for 24h. The effects of Pb on cell proliferation and apoptosis were analyzed with MTT and Annexin V-FITC/PI via flow cytometry, respectively. Expression levels of Fas, Fas-L and caspase-8 in TM3 cells were determined by western blot. As well as the inhibitory effect of the caspase-8 inhibitor Z-IETD-FMK on cell apoptosis. We found that Pb treatment significantly decreased the cellar viability (P<0.05), increased the apoptosis (P<0.01) and the Fas, FasL, and caspase-8 expression levels in Pb-treated cells as compared to the control cells (P<0.05 or P<0.01). Furthermore, the caspase-8 inhibitor effectively block the Pb-induced cell apoptosis. Taken together, our data suggest that Pb-induced TM3 cell toxic effect may involve in the Fas/FasL death receptor signaling pathway. Copyright © 2017. Published by Elsevier B.V.

Involvement of the Fas and Fas ligand in testicular germ cell apoptosis by zearalenone in rat

PubMed Central

Jee, Youngheun; Noh, Eun-Mi; Cho, Eun-Sang

2010-01-01

Zearalenone (ZEA), a nonsteroidal estrogenic mycotoxin, is known to cause testicular toxicity in animals. In the present study, the effects of ZEA on spermatogenesis and possible mechanisms involved in germ cell injury were examined in rats. Ten-week-old Sprague-Dawley rats were treated with 5 mg/kg i.p. of ZEA and euthanized 3, 6, 12, 24 or 48 h after treatment. Histopathologically, spermatogonia and spermatocytes were found to be affected selectively. They were TUNEL-positive and found to be primarily in spermatogenic stages I-VI tubules from 6 h after dosing, increasing gradually until 12 h and then gradually decreasing. Western blot analysis revealed an increase in Fas and Fas ligand (Fas-L) protein levels in the ZEA-treated rats. However, the estrogen receptor (ER)α expression was not changed during the study. Collectively, our data suggest that acute exposure of ZEA induces apoptosis in germ cells of male rats and that this toxicity of ZEA is partially mediated through modulation of Fas and Fas-L systems, though ERα may not play a significant role. PMID:20458151

Ursodeoxycholyl Lysophosphatidylethanolamide Protects Against CD95/FAS-Induced Fulminant Hepatitis.

PubMed

Utaipan, Tanyarath; Otto, Ann-Christin; Gan-Schreier, Hongying; Chunglok, Warangkana; Pathil, Anita; Stremmel, Wolfgang; Chamulitrat, Walee

2017-08-01

Increased activation of CD95/Fas by Fas ligand in viral hepatitis and autoimmunity is involved in pathogenesis of fulminant hepatitis and liver failure. We designed a bile-acid phospholipid conjugate ursodeoxycholyl lysophosphatidylethanolamide (UDCA-LPE with LPE containing oleate at the sn-1) as a hepatoprotectant that was shown to protect against fulminant hepatitis induced by endotoxin. We herein further assessed the ability of UDCA-LPE to prevent death receptor CD95/Fas-induced fulminant hepatitis. C57BL/6 mice were intravenously administered with CD95/Fas agonistic monoclonal antibody (Jo-2) with or without 1 h pretreatment with 50 mg/kg UDCA-LPE. Jo-2 administration caused massive hepatocyte damage as seen by histology, and this was associated with a significant decrease in hepatic phosphatidylcholine (PC), lysoPC, and lysophosphatidylethanolamine levels. By histology, UDCA-LPE pretreatment improved hepatocyte damage and restored the loss of these phospholipids in part by a mechanism involving an inhibition of cytosolic phospholipaseA2 expression. Accordingly, Jo-2 treatment increased hepatic expression of cleaved caspase 8, caspase 3, and poly (ADP-Ribose) polymerase-1, and on the other hand decreased that of anti-apoptotic cellular FLICE-inhibitory protein. UDCA-LPE pretreatment was able to reverse all these changes. Moreover, UDCA-LPE attenuated inflammatory response by lowering the levels of Jo-2-induced proinflammatory cytokines TNF-α, IL-6, and IL-1β in liver and serum. UDCA-LPE was also able to decrease the levels of stimulated Th1/Th17 cytokines in Jo-2-primed isolated splenocytes. Taken together, UDCA-LPE exhibited potent anti-inflammatory effects against CD95/Fas-induced fulminant hepatitis.

Akt-mediated anti-apoptotic effects of substance P in Anti-Fas-induced apoptosis of human tenocytes

PubMed Central

Backman, Ludvig J; Danielson, Patrik

2013-01-01

Substance P (SP) and its receptor, the neurokinin-1 receptor (NK-1 R), are expressed by human tenocytes, and they are both up-regulated in cases of tendinosis, a condition associated with excessive apoptosis. It is known that SP can phosphorylate/activate the protein kinase Akt, which has anti-apoptotic effects. This mechanism has not been studied for tenocytes. The aims of this study were to investigate if Anti-Fas treatment is a good apoptosis model for human tenocytes in vitro, if SP protects from Anti-Fas-induced apoptosis, and by which mechanisms SP mediates an anti-apoptotic response. Anti-Fas treatment resulted in a time- and dose-dependent release of lactate dehydrogenase (LDH), i.e. induction of cell death, and SP dose-dependently reduced the Anti-Fas-induced cell death through a NK-1 R specific pathway. The same trend was seen for the TUNEL assay, i.e. SP reduced Anti-Fas-induced apoptosis via NK-1 R. In addition, it was shown that SP reduces Anti-Fas-induced decrease in cell viability as shown with crystal violet assay. Protein analysis using Western blot confirmed that Anti-Fas induces cleavage/activation of caspase-3 and cleavage of PARP; both of which were inhibited by SP via NK-1 R. Finally, SP treatment resulted in phosphorylation/activation of Akt as shown with Western blot, and it was confirmed that the anti-apoptotic effect of SP was, at least partly, induced through the Akt-dependent pathway. In conclusion, we show that SP reduces Anti-Fas-induced apoptosis in human tenocytes and that this anti-apoptotic effect of SP is mediated through NK-1 R and Akt-specific pathways. PMID:23577779

Relationship between expression of gastrin, somatostatin, Fas/FasL and caspases in large intestinal carcinoma.

PubMed

Mao, Jia-Ding; Wu, Pei; Yang, Ying-Lin; Wu, Jian; Huang, He

2008-05-14

To explore the correlation between the mRNAs and protein expression of gastrin (GAS), somatostatin (SS) and apoptosis index (AI), apoptosis regulation gene Fas/FasL and caspases in large intestinal carcinoma (LIC). Expression of GAS and SS mRNAs were detected by nested RT-PCR in 79 cases of LIC. Cell apoptosis was detected by molecular biology in situ apoptosis detecting methods (TUNEL). Immunohistochemical staining for GAS, SS, Fas/FasL, caspase-3 and caspase-8 was performed according to the standard streptavidin-biotin-peroxidase (S-P) method. There was a significant positive correlation between mRNA and protein expression of GAS and SS (GASrs = 0.99, P < 0.01; SSrs = 0.98, P < 0.01). There was significant difference in positive expression rates of GAS, SS mRNAs and protein among different histological differentiation, histological types and Dukes' stage of LIC. The AI in GAS high and moderate expression groups was significantly lower than that in low expression groups (3.75 +/- 2.38 vs 7.82 +/- 2.38, P < 0.01; 5.51 +/- 2.66 vs 7.82 +/- 2.38, P < 0.01), and the AI in SS high and moderate expression groups was significantly higher than that in low expression groups (9.03 +/- 1.76 vs 5.35 +/- 3.00, P < 0.01; 7.44 +/- 2.67 vs 5.35 +/- 3.00, P < 0.01). There was a significant negative correlation between the integral ratio of GAS to SS and the AI (r(s) = -0.41, P < 0.01). The positive expression rate of FasL in GAS high and moderate expression groups was higher than that in low expression group (90.9% and 81.0% vs 53.2%, P < 0.05). The positive expression rates of Fas, caspase-8 and caspase-3 in SS high (90.0%, 90.0% and 100%) and moderate (80.0%, 70.0%, 75.0%) expression groups were higher than that in low expression group (53.1%, 42.9%, 49.0%) (90.0% and 80.0% vs 53.1%, P < 0.05; 90.0% and 70.0% vs 42.9%, P < 0.05; 100.0% and 75.0% vs 49.0%, P < 0.05). There was a significant positive correlation between the integral ratio of GAS to SS and the semiquantitative

Mitochondrial fatty acid synthesis, fatty acids and mitochondrial physiology.

PubMed

Kastaniotis, Alexander J; Autio, Kaija J; Kerätär, Juha M; Monteuuis, Geoffray; Mäkelä, Anne M; Nair, Remya R; Pietikäinen, Laura P; Shvetsova, Antonina; Chen, Zhijun; Hiltunen, J Kalervo

2017-01-01

Mitochondria and fatty acids are tightly connected to a multiplicity of cellular processes that go far beyond mitochondrial fatty acid metabolism. In line with this view, there is hardly any common metabolic disorder that is not associated with disturbed mitochondrial lipid handling. Among other aspects of mitochondrial lipid metabolism, apparently all eukaryotes are capable of carrying out de novo fatty acid synthesis (FAS) in this cellular compartment in an acyl carrier protein (ACP)-dependent manner. The dual localization of FAS in eukaryotic cells raises the questions why eukaryotes have maintained the FAS in mitochondria in addition to the "classic" cytoplasmic FAS and what the products are that cannot be substituted by delivery of fatty acids of extramitochondrial origin. The current evidence indicates that mitochondrial FAS is essential for cellular respiration and mitochondrial biogenesis. Although both β-oxidation and FAS utilize thioester chemistry, CoA acts as acyl-group carrier in the breakdown pathway whereas ACP assumes this role in the synthetic direction. This arrangement metabolically separates these two pathways running towards opposite directions and prevents futile cycling. A role of this pathway in mitochondrial metabolic sensing has recently been proposed. This article is part of a Special Issue entitled: Lipids of Mitochondria edited by Guenther Daum. Copyright © 2016 Elsevier B.V. All rights reserved.

miR-20a Regulates FAS Expression in Osteosarcoma Cells by Modulating FAS Promoter Activity and Can be Therapeutically Targeted to Inhibit Lung Metastases.

PubMed

Yang, Yuanzheng; Huang, Gangxiong; Zhou, Zhichao; Fewell, Jason G; Kleinerman, Eugenie S

2018-01-01

The metastatic potential of osteosarcoma cells is inversely correlated to cell surface FAS expression. Downregulation of FAS allows osteosarcoma cells to escape FAS ligand-mediated apoptosis when they enter a FAS ligand-positive microenvironment such as the lung. We have previously demonstrated that miR-20a, encoded by the miR-17-92 cluster, downregulates FAS expression in osteosarcoma. We further demonstrated an inverse correlation between FAS expression and miR-20a expression. However, the mechanism of FAS regulation by miR-20a was still unclear. The purpose of the current study was to evaluate the mechanism of FAS regulation by miR-20a in vitro and test the effect of targeting miR-20a in vivo We investigated whether miR-20a's downregulation of FAS was mediated by binding to the 3'-untranslated region (3'-UTR) of FAS mRNA with the consequent induction of mRNA degradation or translational suppression. We identified and mutated two miR-20a binding sites on the FAS mRNA 3'-UTR. Using luciferase reporter assays, we demonstrated that miR-20a did not bind to either the wild-type or mutated FAS 3'-UTR. In contrast, overexpression of miR-20a resulted in downregulation of FAS promoter activity. Similarly, the inhibition of miR-20a increased FAS promoter activity. The critical region identified on the FAS promoter was between -240 bp and -150 bp. Delivery of anti-miR-20a in vivo using nanoparticles in mice with established osteosarcoma lung metastases resulted in upregulation of FAS and tumor growth inhibition. Taken together, our data suggest that miR-20a regulates FAS expression through the modulation of the FAS promoter and that targeting miR-20a using anti-miR-20a has therapeutic potential. Mol Cancer Ther; 17(1); 130-9. ©2017 AACR . ©2017 American Association for Cancer Research.

Association of the Polymorphisms in the Fas/FasL Promoter Regions with Cancer Susceptibility: A Systematic Review and Meta-Analysis of 52 Studies

PubMed Central

Pan, Yuqin; Gao, Tianyi; Deng, Qiwen; Sun, Huiling; Song, Guoqi; Wang, Shukui

2014-01-01

Fas and its ligand (FasL) play an important role in apoptosis and carcinogenesis. Therefore, the potential association of polymorphisms in the Fas (-670A>G, rs1800682; -1377G>A, rs2234767) and FasL (-844C>T, rs763110) with cancer risk has been widely investigated. However, all the currently available results are not always consistent. In this work, we performed a meta-analysis to further determine whether carriers of the polymorphisms in Fas and FasL of interest could confer an altered susceptibility to cancer. All relevant data were retrieved by PubMed and Web of Science, and 52 eligible studies were chosen for this meta-analysis. There was no association of the Fas -670A>G polymorphism with cancer risk in the pooled data. For the Fas -1377G>A and FasL -844C>T polymorphisms, results revealed that the homozygotes of -1377A and -844C were associated with elevated risk of cancer as a whole. Further stratified analysis indicated markedly increased risk for developing breast cancer, gastric cancer, and esophageal cancer, in particular in Asian population. We conclude that carriers of the Fas-1377A and the FasL -844C are more susceptible to the majority of cancers than non-carriers. PMID:24598538

A novel missense substitution (Val1483Ile) in the fatty acid synthase gene (FAS) is associated with percentage of body fat and substrate oxidation rates in nondiabetic Pima Indians.

PubMed

Kovacs, Peter; Harper, Inge; Hanson, Robert L; Infante, Aniello M; Bogardus, Clifton; Tataranni, P Antonio; Baier, Leslie J

2004-07-01

Inhibition of fatty acid synthase (FAS) induces a rapid decline in fat stores in mice, suggesting a role for this enzyme in energy homeostasis. The human FAS gene (FAS) maps to chromosome 17q25, a region previously shown to have suggestive linkage to adiposity in a genome-wide linkage scan for genetic determinants of obesity in Pima Indians. To investigate the potential role of FAS in the pathophysiology of human obesity, the FAS gene was sequenced and 13 single nucleotide polymorphisms (SNPs) were identified. Five representative SNPs were genotyped in 216 full-blooded, nondiabetic Pima Indians for association analyses. A Val1483Ile polymorphism (GTC to ATC; allele frequency of A = 0.10) was associated with percentage of body fat and 24-h substrate oxidation rates measured in a respiratory chamber. Compared with homozygotes for the Val variant, subjects with Ile/x had a lower mean percentage of body fat (30 +/- 1 vs. 33 +/- 1%, P = 0.002; adjusted for age, sex, and family membership) and a lower mean carbohydrate oxidation rate (983 +/- 41 vs. 1,094 +/- 19 kcal/day, P = 0.03), which resulted in a lower mean 24-h respiratory quotient (0.845 +/- 0.01 vs. 0.850 +/- 0.01 kcal/day, P = 0.04; both adjusted for age, sex, family membership, percentage of body fat, and energy balance). Our findings indicate that the Val1483Ile substitution in FAS is protective against obesity in Pima Indians, an effect possibly explained by the role of this gene in the regulation of substrate oxidation.

Blockade of Fas Signaling in Breast Cancer Cells Suppresses Tumor Growth and Metastasis via Disruption of Fas Signaling-initiated Cancer-related Inflammation*

PubMed Central

Liu, Qiuyan; Tan, Qinchun; Zheng, Yuanyuan; Chen, Kun; Qian, Cheng; Li, Nan; Wang, Qingqing; Cao, Xuetao

2014-01-01

Mechanisms for cancer-related inflammation remain to be fully elucidated. Non-apoptotic functions of Fas signaling have been proposed to play an important role in promoting tumor progression. It has yet to be determined if targeting Fas signaling can control tumor progression through suppression of cancer-related inflammation. In the current study we found that breast cancer cells with constitutive Fas expression were resistant to apoptosis induction by agonistic anti-Fas antibody (Jo2) ligation or Fas ligand cross-linking. Higher expression of Fas in human breast cancer tissue has been significantly correlated with poorer prognosis in breast cancer patients. To determine whether blockade of Fas signaling in breast cancer could suppress tumor progression, we prepared an orthotopic xenograft mouse model with mammary cancer cells 4T1 and found that blockade of Fas signaling in 4T1 cancer cells markedly reduced tumor growth, inhibited tumor metastasis in vivo, and prolonged survival of tumor-bearing mice. Mechanistically, blockade of Fas signaling in cancer cells significantly decreased systemic or local recruitment of myeloid derived suppressor cells (MDSCs) in vivo. Furthermore, blockade of Fas signaling markedly reduced IL-6, prostaglandin E2 production from breast cancer cells by impairing p-p38, and activity of the NFκB pathway. In addition, administration of a COX-2 inhibitor and anti-IL-6 antibody significantly reduced MDSC accumulation in vivo. Therefore, blockade of Fas signaling can suppress breast cancer progression by inhibiting proinflammatory cytokine production and MDSC accumulation, indicating that Fas signaling-initiated cancer-related inflammation in breast cancer cells may be a potential target for treatment of breast cancer. PMID:24627480

Fetal alcohol syndrome (FAS) primary prevention through fas diagnosis: II. A comprehensive profile of 80 birth mothers of children with FAS.

PubMed

Astley, S J; Bailey, D; Talbot, C; Clarren, S K

2000-01-01

A 5-year, fetal alcohol syndrome (FAS) primary prevention study was conducted in Washington State to: (1) assess the feasibility of using a FAS diagnostic and prevention clinic as a centre for identifying and targeting primary prevention intervention to high-risk women; (2) generate a comprehensive, lifetime profile of these women; (3) identify factors that have enhanced and/or hindered their ability to achieve abstinence. The results of this study are presented in two parts. Objective 1 is summarized in the preceding paper and objectives 2 and 3 are summarized here. Comprehensive interviews were conducted with 80 women, who had given birth to a child diagnosed with FAS, to document their sociodemographics, reproductive and family planning history, social and healthcare utilization patterns, adverse social experiences, social support network, alcohol use and treatment history, mental health, and intelligence quotient (IQ). These high-risk women were diverse in racial, educational and economic backgrounds, were often victims of abuse, and challenged by mental health issues. Despite their rather harsh psychosocial profile, many demonstrated the ability to overcome their alcohol dependence over time. Relative to the women who had not achieved abstinence, the women who had achieved abstinence had significantly higher IQs, higher household incomes, larger more satisfactory social support networks, were more likely to report a religious affiliation, and were more likely to be receiving mental health treatment for their mental health disorders. The rate of unintended pregnancies and alcohol-exposed pregnancies was substantial. Key barriers to achieving effective family planning were maternal alcohol and drug use, lack of access to birth control and lack of support by their partner to use birth control. A FAS diagnostic and prevention clinic can be used to identify women at high risk for producing children damaged by prenatal alcohol exposure. Primary prevention programmes

Fluoride release from fluoride varnishes under acidic conditions.

PubMed

Lippert, F

2014-01-01

The aim was to investigate the in vitro fluoride release from fluoride varnishes under acidic conditions. Poly(methyl methacrylate) blocks (Perspex, n=3 per group) were painted with 80 ± 5 mg fluoride varnish (n=10) and placed into artificial saliva for 30 min. Then, blocks were placed into either 1% citric acid (pH 2.27) or 0.3% citric acid (pH 3.75) solutions (n=3 per solution and varnish) for 30 min with the solutions being replaced every 5 min. Saliva and acid solutions were analyzed for fluoride content. Data were analyzed using three-way ANOVA (varnish, solution, time). The three-way interaction was significant (p>0.0001). Fluoride release and release patterns varied considerably between varnishes. Fluoride release in saliva varied by a factor of more than 10 between varnishes. Some varnishes (CavityShield, Nupro, ProFluorid, Vanish) showed higher fluoride release in saliva than during the first 5 min of acid exposure, whereas other varnishes (Acclean, Enamel-Pro, MI Varnish, Vella) showed the opposite behavior. There was little difference between acidic solutions. Fluoride release from fluoride varnishes varies considerably and also depends on the dissolution medium. Bearing in mind the limitations of laboratory research, the consumption of acidic drinks after fluoride varnish application should be avoided to optimize the benefit/risk ratio.

Melatonin partially protects 661W cells from H2O2-induced death by inhibiting Fas/FasL-caspase-3.

PubMed

Sánchez-Bretaño, Aída; Baba, Kenkichi; Janjua, Uzair; Piano, Ilaria; Gargini, Claudia; Tosini, Gianluca

2017-01-01

Previous studies have shown that melatonin (MEL) signaling is involved in the modulation of photoreceptor viability during aging. Recent work by our laboratory suggested that MEL may protect cones by modulating the Fas/FasL-caspase-3 pathway. In this study, we first investigated the presence of MEL receptors (MT 1 and MT 2 ) in 661W cells, then whether MEL can prevent H 2 O 2 -induced cell death, and last, through which pathway MEL confers protection. The mRNA and proteins of the MEL receptors were detected with quantitative PCR (q-PCR) and immunocytochemistry, respectively. To test the protective effect of MEL, 661W cells were treated with H 2 O 2 for 2 h in the presence or absence of MEL, a MEL agonist, and an antagonist. To study the pathways involved in H 2 O 2 -mediated cell death, a Fas/FasL antagonist was used before the exposure to H 2 O 2 . Finally, Fas/FasL and caspase-3 mRNA was analyzed with q-PCR and immunocytochemistry in cells treated with H 2 O 2 and/or MEL. Cell viability was analyzed by using Trypan Blue. Both MEL receptors (MT 1 and MT 2 ) were detected at the mRNA and protein levels in 661W cells. MEL partially prevented H 2 O 2 -mediated cell death (20-25%). This effect was replicated with IIK7 (a melatonin receptor agonist) when used at a concentration of 1 µM. Preincubation with luzindole (a melatonin receptor antagonist) blocked MEL protection. Kp7-6, an antagonist of Fas/FasL, blocked cell death caused by H 2 O 2 similarly to what was observed for MEL. Fas, FasL, and caspase-3 expression was increased in cells treated with H 2 O 2 , and this effect was prevented by MEL. Finally, MEL treatment partially prevented the activation of caspase-3 caused by H 2 O 2 . The results demonstrate that MEL receptors are present and functional in 661W cells. MEL can prevent photoreceptor cell death induced by H 2 O 2 via the inhibition of the proapoptotic pathway Fas/FasL-caspase-3.

The Cytocidal Activity of OK‐432‐activated Mononuclear Cells against Human Glioma Cells is Partly Mediated through the Fas Ligand/Fas System

PubMed Central

Toda, Keisuke; Shiraishi, Tetsuya; Hirotsu, Tatsumi; Fukuyama, Kouzou; Mineta, Toshihiro; Kawaguchi, Shojiro; Tabuchi, Kazuo

1996-01-01

We have been applying an adoptive immunotherapy protocol to patients with malignant brain tumors using OK‐432‐activated peripheral blood mononuclear cells (OK‐MCs). In order to elucidate the mechanism of OK‐MCs' cytotoxicity, we examined the expression of Fas ligand mRNA in OK‐MCs and the cytocidal activity of these cells against a human glioma cell line, T98G which expresses a high level of Fas. The expression of Fas ligand mRNA was low in non‐treated peripheral blood mononuclear cells and was elevated by treatment with OK‐432, irrespective of the dose employed. Apoptosis of T98G cells induced by OK‐MCs was unequivocally inhibited by the pretreatment of T98G cells with ZB4 monoclonal antibody, which binds to Fas and blocks the binding of Fas ligand to Fas. These data indicate that the cytotoxic activity of OK‐MCs via apoptosis seems to be at least partly mediated by the Fas ligand/Fas system. Adoptive immunotherapy using the Fas ligand/Fas system could be a new treatment modality for human malignant brain tumors. PMID:8878461

Gonadal steroids modulate Fas-induced apoptosis of lactotropes and somatotropes.

PubMed

Jaita, Gabriela; Zárate, Sandra; Ferrari, Luciana; Radl, Daniela; Ferraris, Jimena; Eijo, Guadalupe; Zaldivar, Verónica; Pisera, Daniel; Seilicovich, Adriana

2011-02-01

We have previously reported that Fas activation induces apoptosis of anterior pituitary cells from rats at proestrus but not at diestrus and in an estrogen-dependent manner. In this study, we evaluated the effect of Fas activation on apoptosis of lactotropes and somatotropes during the estrous cycle and explored the action of gonadal steroids on Fas-induced apoptosis. Also, we studied whether changes in Fas expression are involved in the apoptotic response of anterior pituitary cells. Fas activation increased the percentage of TUNEL-positive lactotropes and somatotropes at proestrus but not at diestrus. FasL triggered apoptosis of somatotropes only when cells from ovariectomized rats were cultured in the presence of 17 β-estradiol (E2). Progesterone (P4) blocked the apoptotic action of the Fas/FasL system in lactotropes and somatotropes incubated with E2. Both E2 and P4 increased the percentage of cells expressing Fas at the cell membrane. Our results show that Fas activation induces apoptosis of lactotropes and somatotropes at proestrus but not at diestrus. Gonadal steroids may be involved in the apoptotic response of lactotropes and somatotropes, suggesting that Fas activation is implicated in the renewal of these pituitary subpopulations during the estrous cycle. The effect of gonadal steroids on Fas expression may be only partially involved in regulation of the Fas/FasL apoptotic pathway in the anterior pituitary gland.

TNFα sensitizes neuroblastoma cells to FasL-, cisplatin- and etoposide-induced cell death by NF-κB-mediated expression of Fas.

PubMed

Galenkamp, Koen Mo; Carriba, Paulina; Urresti, Jorge; Planells-Ferrer, Laura; Coccia, Elena; Lopez-Soriano, Joaquín; Barneda-Zahonero, Bruna; Moubarak, Rana S; Segura, Miguel F; Comella, Joan X

2015-03-19

Patients with high-risk neuroblastoma (NBL) tumors have a high mortality rate. Consequently, there is an urgent need for the development of new treatments for this condition. Targeting death receptor signaling has been proposed as an alternative to standard chemo- and radio-therapies in various tumors. In NBL, this therapeutic strategy has been largely disregarded, possibly because ~50-70% of all human NBLs are characterized by caspase-8 silencing. However, the expression of caspase-8 is detected in a significant group of NBL patients, and they could therefore benefit from treatments that induce cell death through death receptor activation. Given that cytokines, such as TNFα, are able to upregulate Fas expression, we sought to address the therapeutic relevance of co-treatment with TNFα and FasL in NBL. For the purpose of the study we used a set of eight NBL cell lines. Here we explore the cell death induced by TNFα, FasL, cisplatin, and etoposide, or a combination thereof by Hoechst staining and calcein viability assay. Further assessment of the signaling pathways involved was performed by caspase activity assays and Western blot experiments. Characterization of Fas expression levels was achieved by qRT-PCR, cell surface biotinylation assays, and cytometry. We have found that TNFα is able to increase FasL-induced cell death by a mechanism that involves the NF-κB-mediated induction of the Fas receptor. Moreover, TNFα sensitized NBL cells to DNA-damaging agents (i.e. cisplatin and etoposide) that induce the expression of FasL. Priming to FasL-, cisplatin-, and etoposide-induced cell death could only be achieved in NBLs that display TNFα-induced upregulation of Fas. Further analysis denotes that the high degree of heterogeneity between NBLs is also manifested in Fas expression and modulation thereof by TNFα. In summary, our findings reveal that TNFα sensitizes NBL cells to FasL-induced cell death by NF-κB-mediated upregulation of Fas and unveil a new

Transfer of Fas (CD95) protein from the cell surface to the surface of polystyrene beads coated with anti-Fas antibody clone CH-11

PubMed Central

Sawai, H.; Domae, N.

2010-01-01

Mouse monoclonal anti-Fas (CD95) antibody clone CH-11 has been widely used in research on apoptosis. CH-11 has the ability to bind to Fas protein on cell surface and induce apoptosis. Here, we used polystyrene beads coated with CH-11 to investigate the role of lipid rafts in Fas-mediated apoptosis in SKW6.4 cells. Unexpectedly, by treatment of the cells with CH-11-coated beads Fas protein was detached from cell surface and transferred to the surface of CH-11-coated beads. Western blot analysis showed that Fas protein containing both extracellular and intracellular domains was attached to the beads. Fas protein was not transferred from the cells to the surface of the beads coated with other anti-Fas antibodies or Fas ligand. Similar phenomenon was observed in Jurkat T cells. Furthermore, CH-11-induced apoptosis was suppressed by pretreatment with CH-11-coated beads in Jurkat cells. These results suggest that CH-11 might possess distinct properties on Fas protein compared with other anti-Fas antibodies or Fas ligand, and also suggest that caution should be needed to use polystyrene beads coated with antibodies such as CH-11. PMID:20353915

Identification of the Calmodulin-Binding Domains of Fas Death Receptor

PubMed Central

Chang, Bliss J.; Samal, Alexandra B.; Vlach, Jiri; Fernandez, Timothy F.; Brooke, Dewey; Prevelige, Peter E.; Saad, Jamil S.

2016-01-01

The extrinsic apoptotic pathway is initiated by binding of a Fas ligand to the ectodomain of the surface death receptor Fas protein. Subsequently, the intracellular death domain of Fas (FasDD) and that of the Fas-associated protein (FADD) interact to form the core of the death-inducing signaling complex (DISC), a crucial step for activation of caspases that induce cell death. Previous studies have shown that calmodulin (CaM) is recruited into the DISC in cholangiocarcinoma cells and specifically interacts with FasDD to regulate the apoptotic/survival signaling pathway. Inhibition of CaM activity in DISC stimulates apoptosis significantly. We have recently shown that CaM forms a ternary complex with FasDD (2:1 CaM:FasDD). However, the molecular mechanism by which CaM binds to two distinct FasDD motifs is not fully understood. Here, we employed mass spectrometry, nuclear magnetic resonance (NMR), biophysical, and biochemical methods to identify the binding regions of FasDD and provide a molecular basis for the role of CaM in Fas–mediated apoptosis. Proteolytic digestion and mass spectrometry data revealed that peptides spanning residues 209–239 (Fas-Pep1) and 251–288 (Fas-Pep2) constitute the two CaM-binding regions of FasDD. To determine the molecular mechanism of interaction, we have characterized the binding of recombinant/synthetic Fas-Pep1 and Fas-Pep2 peptides with CaM. Our data show that both peptides engage the N- and C-terminal lobes of CaM simultaneously. Binding of Fas-Pep1 to CaM is entropically driven while that of Fas-Pep2 to CaM is enthalpically driven, indicating that a combination of electrostatic and hydrophobic forces contribute to the stabilization of the FasDD–CaM complex. Our data suggest that because Fas-Pep1 and Fas-Pep2 are involved in extensive intermolecular contacts with the death domain of FADD, binding of CaM to these regions may hinder its ability to bind to FADD, thus greatly inhibiting the initiation of apoptotic signaling

Fas-Fas ligand interactions are essential for the binding to and killing of activated macrophages by gamma delta T cells.

PubMed

Dalton, Jane E; Howell, Gareth; Pearson, Jayne; Scott, Phillip; Carding, Simon R

2004-09-15

Gammadelta T cells have a direct role in resolving the host immune response to infection by eliminating populations of activated macrophages. Macrophage reactivity resides within the Vgamma1/Vdelta6.3 subset of gammadelta T cells, which have the ability to kill activated macrophages following infection with Listeria monocytogenes (Lm). However, it is not known how gammadelta T cell macrophage cytocidal activity is regulated, or what effector mechanisms gammadelta T cells use to kill activated macrophages. Using a macrophage-T cell coculture system in which peritoneal macrophages from naive or Lm-infected TCRdelta-/- mice were incubated with splenocytes from wild-type and Fas ligand (FasL)-deficient mice (gld), the ability of Vgamma1 T cells to bind macrophages was shown to be dependent upon Fas-FasL interactions. Combinations of anti-TCR and FasL Abs completely abolished binding to and killing of activated macrophages by Vgamma1 T cells. In addition, confocal microscopy showed that Fas and the TCR colocalized on Vgamma1 T cells at points of contact with macrophages. Collectively, these studies identify an accessory or coreceptor-like function for Fas-FasL that is essential for the interaction of Vgamma1 T cells with activated macrophages and their elimination during the resolution stage of pathogen-induced immune responses. Copyright 2004 The American Association of Immunologists, Inc.

Fas/APO-1 (CD95) expression in myelodysplastic syndromes.

PubMed

Lepelley, P; Grardel, N; Erny, O; Iaru, T; Obein, V; Cosson, A; Fenaux, P

1998-07-01

Increased apoptosis of myeloid precursors appears to contribute to the pathophysiology of cytopenias in myelodysplastic syndromes (MDS). Fas /APO-1(CD95) is a cell surface protein inducing an apoptotic signal after its binding to Fas ligand or to a functional anti-Fas antibody. Here we studied Fas expression by immunocytochemistry on marrow slides from 30 cases of MDS. Increased Fas expression in erythroblasts and/or immature granulocytes, compared to controls, was seen in 12 (40%) of the cases. In addition, in 16 of the 18 cases with > or = 5% marrow blasts, a variable proportion of blasts expressed Fas. Increased apoptosis was found by morphological analysis and/or TUNEL technique in marrow cells from 8 of the 26 cases analyzed (31%) The ability of Fas antigen to trigger apoptosis was studied after addition of a functional anti Fas antibody in 5 of the patients with Fas overexpression. Addition of this antibody, however, only lead to mild increase of apoptosis in immature granulocytes (but not other myeloid cells) in 2 of the 5 cases. Thus, increased Fas expression is seen in myeloid and/or blast cells in the majority of MDS cases. However, the relationship between this finding and increased apoptosis in MDS still remains to be established.

Relationship between expression of gastrin, somatostatin, Fas/FasL and caspases in large intestinal carcinoma

PubMed Central

Mao, Jia-Ding; Wu, Pei; Yang, Ying-Lin; Wu, Jian; Huang, He

2008-01-01

AIM: To explore the correlation between the mRNAs and protein expression of gastrin (GAS), somatostatin (SS) and apoptosis index (AI), apoptosis regulation gene Fas/FasL and caspases in large intestinal carcinoma (LIC). METHODS: Expression of GAS and SS mRNAs were detected by nested RT-PCR in 79 cases of LIC. Cell apoptosis was detected by molecular biology in situ apoptosis detecting methods (TUNEL). Immunohistochemical staining for GAS, SS, Fas/FasL, caspase-3 and caspase-8 was performed according to the standard streptavidin-biotin-peroxidase (S-P) method. RESULTS: There was a significant positive correlation between mRNA and protein expression of GAS and SS (GASrs=0.99, P < 0.01; SSrs = 0.98, P < 0.01). There was significant difference in positive expression rates of GAS, SS mRNAs and protein among different histological differentiation, histological types and Dukes’ stage of LIC. The AI in GAS high and moderate expression groups was significantly lower than that in low expression groups (3.75 ± 2.38 vs 7.82 ± 2.38, P < 0.01; 5.51 ± 2.66 vs 7.82 ± 2.38, P < 0.01), and the AI in SS high and moderate expression groups was significantly higher than that in low expression groups (9.03 ± 1.76 vs 5.35 ± 3.00, P < 0.01; 7.44 ± 2.67 vs 5.35 ± 3.00, P < 0.01). There was a significant negative correlation between the integral ratio of GAS to SS and the AI (rs = -0.41, P < 0.01). The positive expression rate of FasL in GAS high and moderate expression groups was higher than that in low expression group (90.9% and 81.0% vs 53.2%, P < 0.05). The positive expression rates of Fas, caspase-8 and caspase-3 in SS high (90.0%, 90.0% and 100%) and moderate (80.0%, 70.0%, 75.0%) expression groups were higher than that in low expression group (53.1%, 42.9%, 49.0%) (90.0% and 80.0% vs 53.1%, P < 0.05; 90.0% and 70.0% vs 42.9%, P < 0.05; 100.0% and 75.0% vs 49.0%, P < 0.05). There was a significant positive correlation between the integral ratio of GAS to SS and the

Akt-mediated anti-apoptotic effects of substance P in Anti-Fas-induced apoptosis of human tenocytes.

PubMed

Backman, Ludvig J; Danielson, Patrik

2013-06-01

Substance P (SP) and its receptor, the neurokinin-1 receptor (NK-1 R), are expressed by human tenocytes, and they are both up-regulated in cases of tendinosis, a condition associated with excessive apoptosis. It is known that SP can phosphorylate/activate the protein kinase Akt, which has anti-apoptotic effects. This mechanism has not been studied for tenocytes. The aims of this study were to investigate if Anti-Fas treatment is a good apoptosis model for human tenocytes in vitro, if SP protects from Anti-Fas-induced apoptosis, and by which mechanisms SP mediates an anti-apoptotic response. Anti-Fas treatment resulted in a time- and dose-dependent release of lactate dehydrogenase (LDH), i.e. induction of cell death, and SP dose-dependently reduced the Anti-Fas-induced cell death through a NK-1 R specific pathway. The same trend was seen for the TUNEL assay, i.e. SP reduced Anti-Fas-induced apoptosis via NK-1 R. In addition, it was shown that SP reduces Anti-Fas-induced decrease in cell viability as shown with crystal violet assay. Protein analysis using Western blot confirmed that Anti-Fas induces cleavage/activation of caspase-3 and cleavage of PARP; both of which were inhibited by SP via NK-1 R. Finally, SP treatment resulted in phosphorylation/activation of Akt as shown with Western blot, and it was confirmed that the anti-apoptotic effect of SP was, at least partly, induced through the Akt-dependent pathway. In conclusion, we show that SP reduces Anti-Fas-induced apoptosis in human tenocytes and that this anti-apoptotic effect of SP is mediated through NK-1 R and Akt-specific pathways. © 2013 The Authors Journal of Cellular and Molecular Medicine Published by Foundation for Cellular and Molecular Medicine/Blackwell Publishing Ltd.

Use of Lentiviral Particles As a Cell Membrane-Based mFasL Delivery System for In Vivo Treatment of Inflammatory Arthritis.

PubMed

Rodríguez-Frade, José M; Guedán, Anabel; Lucas, Pilar; Martínez-Muñoz, Laura; Villares, Ricardo; Criado, Gabriel; Balomenos, Dimitri; Reyburn, Hugh T; Mellado, Mario

2017-01-01

During budding, lentiviral particles (LVP) incorporate cell membrane proteins in the viral envelope. We explored the possibility of harnessing this process to generate LVP-expressing membrane proteins of therapeutic interest and studied the potential of these tools to treat different pathologies. Fas-mediated apoptosis is central to the maintenance of T cell homeostasis and prevention of autoimmune processes. We prepared LVP that express murine FasL on their surface. Our data indicate that mFasL-bearing LVP induce caspase 3 and 9 processing, cytochrome C release, and significantly more cell death than control LVP in vitro . This cytotoxicity is blocked by the caspase inhibitor Z-VAD. Analysis of the application of these reagents for the treatment of inflammatory arthritis in vivo suggests that FasL-expressing LVP could be useful for therapy in autoimmune diseases such as rheumatoid arthritis, where there is an excess of Fas-expressing activated T cells in the joint. LVP could be a vehicle not only for mFasL but also for other membrane-bound proteins that maintain their native conformation and might mediate biological activities.

Effects of celecoxib on cell apoptosis and Fas, FasL and Bcl-2 expression in a BGC-823 human gastric cancer cell line.

PubMed

Li, Qian; Peng, Jie; Liu, Ting; Zhang, Guiying

2017-09-01

Fas, which is an apoptotic-related protein, has an important role in cell apoptosis. Fas ligand (FasL) binds to Fas and activates apoptosis signal transduction. We previously demonstrated that the efficiency of celecoxib inhibited the proliferation and apoptosis of HT-29 colon cancer cell line. The BGC823 cell line was used as an experimental model to evaluate the potential role of celecoxib on gastric cancer cell apoptosis. Inhibitory effects of celecoxib on cell viability were determined by MTT assay. Cell apoptosis was evaluated by flow cytometric analysis and laser confocal microscopy. The results of the present study demonstrated that celecoxib inhibited the viability of BGC823 cells in a concentration- and time-dependent manner. Furthermore, the effect of BGC823 cells apoptosis was increased in a concentration-dependent manner. Western blotting was used to determine the protein expression levels of Fas, FasL, and B-cell lymphoma-2 (Bcl-2). During the celecoxib-induced apoptosis of BGC823 cells, celecoxib upregulated Fas expression and downregulated FasL and Bcl-2 expression in a concentration-dependent manner. These results suggest that celecoxib inhibited the growth and induced apoptosis of BGC823 gastric cancer cells by regulating the protein expression of Fas, FasL and Bcl-2.

Transcriptional regulation of fatty acid biosynthesis in mycobacteria

PubMed Central

Mondino, S.; Gago, G.; Gramajo, H.

2013-01-01

SUMMARY The main purpose of our study is to understand how mycobacteria exert control over the biosynthesis of their membrane lipids and find out the key components of the regulatory network that control fatty acid biosynthesis at the transcriptional level. In this paper we describe the identification and purification of FasR, a transcriptional regulator from Mycobacterium sp. that controls the expression of the fatty acid synthase (fas) and the 4-phosphopantetheinyl transferase (acpS) encoding genes, whose products are involved in the fatty acid and mycolic acid biosynthesis pathways. In vitro studies demonstrated that fas and acpS genes are part of the same transcriptional unit and that FasR specifically binds to three conserved operator sequences present in the fas-acpS promoter region (Pfas). The construction and further characterization of a fasR conditional mutant confirmed that FasR is a transcriptional activator of the fas-acpS operon and that this protein is essential for mycobacteria viability. Furthermore, the combined used of Pfas-lacZ fusions in different fasR backgrounds and electrophoretic mobility shift assays experiments, strongly suggested that long-chain acyl-CoAs are the effector molecules that modulate the affinity of FasR for its DNA binding sequences and therefore the expression of the essential fas-acpS operon. PMID:23721164

7 CFR 1484.70 - Must Cooperators report to FAS?

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 10 2010-01-01 2010-01-01 false Must Cooperators report to FAS? 1484.70 Section 1484... AGRICULTURAL COMMODITIES Reporting, Evaluation, and Compliance § 1484.70 Must Cooperators report to FAS? (a... contribution report is available on the FAS home page (http://www.fas.usda.gov/mos/programs/fnotice.html) on...

7 CFR 1484.70 - Must Cooperators report to FAS?

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 10 2011-01-01 2011-01-01 false Must Cooperators report to FAS? 1484.70 Section 1484... AGRICULTURAL COMMODITIES Reporting, Evaluation, and Compliance § 1484.70 Must Cooperators report to FAS? (a... contribution report is available on the FAS home page (http://www.fas.usda.gov/mos/programs/fnotice.html) on...

7 CFR 1484.70 - Must Cooperators report to FAS?

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 10 2013-01-01 2013-01-01 false Must Cooperators report to FAS? 1484.70 Section 1484... COMMODITIES Reporting, Evaluation, and Compliance § 1484.70 Must Cooperators report to FAS? (a) End-of-year... is available on the FAS home page (http://www.fas.usda.gov/mos/programs/fnotice.html) on the Internet...

7 CFR 1484.70 - Must Cooperators report to FAS?

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 10 2014-01-01 2014-01-01 false Must Cooperators report to FAS? 1484.70 Section 1484... COMMODITIES Reporting, Evaluation, and Compliance § 1484.70 Must Cooperators report to FAS? (a) End-of-year... is available on the FAS home page (http://www.fas.usda.gov/mos/programs/fnotice.html) on the Internet...

7 CFR 1484.70 - Must Cooperators report to FAS?

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 10 2012-01-01 2012-01-01 false Must Cooperators report to FAS? 1484.70 Section 1484... COMMODITIES Reporting, Evaluation, and Compliance § 1484.70 Must Cooperators report to FAS? (a) End-of-year... is available on the FAS home page (http://www.fas.usda.gov/mos/programs/fnotice.html) on the Internet...

Prenatal Exposure of Mice to Diethylstilbestrol Disrupts T-Cell Differentiation by Regulating Fas/Fas Ligand Expression through Estrogen Receptor Element and Nuclear Factor-κB Motifs

PubMed Central

Singh, Narendra P.; Singh, Udai P.; Nagarkatti, Prakash S.

2012-01-01

Prenatal exposure to diethylstilbestrol (DES) is known to cause altered immune functions and increased susceptibility to autoimmune disease in humans. In the current study, we investigated the effect of prenatal exposure to DES on thymocyte differentiation involving apoptotic pathways. Prenatal DES exposure caused thymic atrophy, apoptosis, and up-regulation of Fas and Fas ligand (FasL) expression in thymocytes. To examine the mechanism underlying DES-mediated regulation of Fas and FasL, we performed luciferase assays using T cells transfected with luciferase reporter constructs containing full-length Fas or FasL promoters. There was significant luciferase induction in the presence of Fas or FasL promoters after DES exposure. Further analysis demonstrated the presence of several cis-regulatory motifs on both Fas and FasL promoters. When DES-induced transcription factors were analyzed, estrogen receptor element (ERE), nuclear factor κB (NF-κB), nuclear factor of activated T cells (NF-AT), and activator protein-1 motifs on the Fas promoter, as well as ERE, NF-κB, and NF-AT motifs on the FasL promoter, showed binding affinity with the transcription factors. Electrophoretic mobility-shift assays were performed to verify the binding affinity of cis-regulatory motifs of Fas or FasL promoters with transcription factors. There was shift in mobility of probes (ERE or NF-κB2) of both Fas and FasL in the presence of nuclear proteins from DES-treated cells, and the shift was specific to DES because these probes failed to shift their mobility in the presence of nuclear proteins from vehicle-treated cells. Together, the current study demonstrates that prenatal exposure to DES triggers significant alterations in apoptotic molecules expressed on thymocytes, which may affect T-cell differentiation and cause long-term effects on the immune functions. PMID:22888145

Prenatal exposure of mice to diethylstilbestrol disrupts T-cell differentiation by regulating Fas/Fas ligand expression through estrogen receptor element and nuclear factor-κB motifs.

PubMed

Singh, Narendra P; Singh, Udai P; Nagarkatti, Prakash S; Nagarkatti, Mitzi

2012-11-01

Prenatal exposure to diethylstilbestrol (DES) is known to cause altered immune functions and increased susceptibility to autoimmune disease in humans. In the current study, we investigated the effect of prenatal exposure to DES on thymocyte differentiation involving apoptotic pathways. Prenatal DES exposure caused thymic atrophy, apoptosis, and up-regulation of Fas and Fas ligand (FasL) expression in thymocytes. To examine the mechanism underlying DES-mediated regulation of Fas and FasL, we performed luciferase assays using T cells transfected with luciferase reporter constructs containing full-length Fas or FasL promoters. There was significant luciferase induction in the presence of Fas or FasL promoters after DES exposure. Further analysis demonstrated the presence of several cis-regulatory motifs on both Fas and FasL promoters. When DES-induced transcription factors were analyzed, estrogen receptor element (ERE), nuclear factor κB (NF-κB), nuclear factor of activated T cells (NF-AT), and activator protein-1 motifs on the Fas promoter, as well as ERE, NF-κB, and NF-AT motifs on the FasL promoter, showed binding affinity with the transcription factors. Electrophoretic mobility-shift assays were performed to verify the binding affinity of cis-regulatory motifs of Fas or FasL promoters with transcription factors. There was shift in mobility of probes (ERE or NF-κB2) of both Fas and FasL in the presence of nuclear proteins from DES-treated cells, and the shift was specific to DES because these probes failed to shift their mobility in the presence of nuclear proteins from vehicle-treated cells. Together, the current study demonstrates that prenatal exposure to DES triggers significant alterations in apoptotic molecules expressed on thymocytes, which may affect T-cell differentiation and cause long-term effects on the immune functions.

Gallic Acid Induces Apoptosis in Human Gastric Adenocarcinoma Cells.

PubMed

Tsai, Chung-Lin; Chiu, Ying-Ming; Ho, Tin-Yun; Hsieh, Chin-Tung; Shieh, Dong-Chen; Lee, Yi-Ju; Tsay, Gregory J; Wu, Yi-Ying

2018-04-01

Gastric cancer is one of the most common malignant cancers with a poor prognosis and high mortality rate worldwide. Current treatment of gastric cancer includes surgery and chemotherapy as the main modalities, but the potentially severe side-effects of chemotherapy present a considerable challenge. Gallic acid is a trihydroxybenzoic acid found to exert an anticancer effect against a variety of cancer cells. The purpose of this study was to determine the anti-cancer activity of Galla chinensis and its main component gallic acid on human gastric adenocarcinoma cells. MTT assay and cell death ELISA were used to determine the apoptotic effect of Gallic Chinensis and gallic acid on human gastric adenocarcinoma cells. To determine the pathway and relevant components by which gallic acid-induced apoptosis is mediated through, cells were transfected with siRNA (Fas, FasL, DR5, p53) using Lipofectamine 2000. Reults: Gallic Chinensis and gallic acid induced apoptosis of human gastric adenocarcinoma cells. Gallic acid induced up-regulation of Fas, FasL, and DR5 expression in AGS cells. Transfection of cells with Fas, FasL, or DR5 siRNA reduced gallic acid-induced cell death. In addition, p53 was shown to be involved in gallic acid-mediated Fas, FasL, and DR5 expression as well as cell apoptosis in AGS cells. These results suggest that gallic acid has a potential role in the treatment of gastric cancer. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Trifluoperazine Regulation of Calmodulin Binding to Fas: A Computational Study

PubMed Central

Pan, Di; Yan, Qi; Chen, Yabing; McDonald, Jay M; Song, Yuhua

2011-01-01

Death-inducing signaling complex (DISC) formation is a critical step in Fas-mediated signaling for apoptosis. Previous experiments have demonstrated that the calmodulin (CaM) antagonist, trifluoperazine (TFP) regulates CaM-Fas binding and affects Fas-mediated DISC formation. In this study, we investigated the anti-cooperative characteristics of TFP binding to CaM and the effect of TFP on the CaM-Fas interaction from both structural and thermodynamic perspectives using combined molecular dynamics simulations and binding free energy analyses. We studied the interactions of different numbers of TFP molecules with CaM and explored the effects of the resulting conformational changes in CaM on CaM-Fas binding. Results from these analyses showed that the number of TFP molecules bound to CaM directly influenced α-helix formation and hydrogen bond occupancy within the α-helices of CaM, contributing to the conformational and motion changes in CaM. These changes affected CaM binding to Fas, resulting in secondary structural changes in Fas and conformational and motion changes of Fas in CaM-Fas complexes, potentially perturbing the recruitment of Fas-associated death domain (FADD) for DISC formation. The computational results from this study reveal the structural and molecular mechanisms that underlie the role of the CaM antagonist, TFP, in regulation of CaM-Fas binding and Fas-mediated DISC formation in a concentration-dependent manner. PMID:21656570

Divergent Effects of Neutrophils on Fas-Induced Pulmonary Inflammation, Apoptosis, and Lung Damage.

PubMed

Bruns, Bastian; Hönle, Theresia; Kellermann, Philipp; Ayala, Alfred; Perl, Mario

2017-02-01

Pulmonary Fas activation is essential in the pathogenesis of the acute respiratory distress syndrome. It remains unclear whether Fas-induced lung injury is dependent on neutrophils or mainly triggered by epithelial cell apoptosis. The contribution of lung epithelial cells (LEC) and alveolar macrophages (AM) remains elusive.Mice were neutrophil reduced prior to intratracheal instillation of Fas-activating (Jo2) or isotype antibody for 6 or 18 h. LEC and AM were incubated with Jo2 and in the presence of nuclear factor kappa B, p-38 mitogen activated protein kinase (p38MAPK), or extracellular signal regulating kinase 1/2 (ERK1/2) inhibitors. Cytokines were assessed by cytometric bead array or ELISA. Apoptosis was quantified via active caspase-3 Western blotting and Terminal Deoxynucleotide Transferase dUTP Nick End Labeling (TUNEL). Lung injury was assessed by bronchoalveolar lavage fluid (BALF) protein concentration and lung histology.KC, IL-6, and MCP-1 were markedly increased in lung, plasma, and BALF 18 h after Jo2 in the presence of neutrophils; in neutrophil-reduced mice lungs, MCP-1, but not KC or IL-6, was even further enhanced. Six hours after Jo2, BALF protein was markedly increased only in the presence of neutrophils. Apoptosis remained unaffected by neutrophil reduction. AM released MCP-1 and underwent apoptosis at lower concentrations of Jo2 than LEC. Inhibition of p38MAPK significantly increased, while inhibition of ERK1/2 reduced AM and LEC apoptosis.In conclusion, neutrophils are a necessary component of Fas-induced lung damage, while not affecting lung apoptosis directly per se. LEC display higher resistance to Fas-triggered inflammation and apoptosis than AM.

Fas Binding to Calmodulin Regulates Apoptosis in Osteoclasts*

PubMed Central

Wu, Xiaojun; Ahn, Eun-Young; McKenna, Margaret A.; Yeo, Hyeonju; McDonald, Jay M.

2005-01-01

Promotion of osteoclast apoptosis is one therapeutic approach to osteoporosis. Calmodulin, the major intracellular Ca2+ receptor, modulates both osteoclastogenesis and bone resorption. The calmodulin antagonist, trifluoperazine, rescues bone loss in ovariectomized mice (Zhang, L., Feng, X., and McDonald, J. M. (2003) Endocrinology 144, 4536–4543). We show here that a 3-h treatment of mouse osteoclasts with either of the calmodulin antagonists, tamoxifen or trifluoperazine, induces osteoclast apoptosis dose-dependently. Tamoxifen, 10 μm, and trifluoperazine, 10 μm, induce 7.3 ± 1.8-fold and 5.3 ± 0.9-fold increases in osteoclast apoptosis, respectively. In Jurkat cells, calmodulin binds to Fas, the death receptor, and this binding is regulated during Fas-mediated apoptosis (Ahn, E. Y., Lim, S. T., Cook, W. J., and McDonald, J. M. (2004) J. Biol. Chem. 279, 5661–5666). In osteoclasts, calmodulin also binds Fas. When osteoclasts are treated with 10 μm trifluoperazine, the binding between Fas and calmodulin is dramatically decreased at 15 min and gradually recovers by 60 min. A point mutation of the Fas death domain in the Lpr−cg mouse renders Fas inactive. Using glutathione S-transferase fusion proteins, the human Fas cytoplasmic domain is shown to bind calmodulin, whereas a point mutation (V254N) comparable with the Lpr−cg mutation in mice has markedly reduced calmodulin binding. Osteoclasts derived from Lpr−cg mice have diminished calmodulin/Fas binding and are more sensitive to calmodulin antagonist-induced apoptosis than those from wild-type mice. Both tamoxifen- and trifluoperazine-induced apoptosis are increased 1.6 ± 0.2-fold in Lpr−cg-derived osteoclasts compared with osteoclasts derived from wild-type mice. In summary, calmodulin antagonists induce apoptosis in osteoclasts by a mechanism involving interference with calmodulin binding to Fas. The effects of calmodulin/Fas binding on calmodulin antagonist-induced apoptosis may open a new

CD40 activation induces apoptosis in cultured human hepatocytes via induction of cell surface fas ligand expression and amplifies fas-mediated hepatocyte death during allograft rejection.

PubMed

Afford, S C; Randhawa, S; Eliopoulos, A G; Hubscher, S G; Young, L S; Adams, D H

1999-01-18

We propose that a novel mechanism of hepatocyte apoptosis, involving a cooperative interaction between CD40 and Fas, is involved in the hepatocyte loss of chronic liver allograft rejection. We detected increased hepatocyte expression of Fas, Fas ligand (FasL), and CD40 associated with dropout of centrilobular (acinar zone 3) hepatocytes in chronic allograft rejection. Expression of CD40 ligand (CD40L) was also increased but was largely restricted to CD68(+) macrophages. A functional role for CD40 and Fas in hepatocyte apoptosis was demonstrated in vitro using primary human hepatocytes and the HepG2 cell line in both of which apoptosis was induced, not only by cross-linking Fas directly but also via CD40 activation. Our data suggest that CD40 activation induces apoptosis via Fas because (a) ligation of CD40 upregulated hepatocyte FasL expression, and (b) apoptosis induced via activation of CD40 was prevented by a neutralizing monoclonal antibody to FasL. Thus, CD40 engagement triggers apoptosis of human hepatocytes and might amplify Fas-dependent hepatocyte apoptosis in chronic rejection and other inflammatory liver diseases in which Fas-mediated apoptosis is involved.

Relationship between plasma levels of cardiac natriuretic peptides and soluble Fas: plasma soluble Fas as a prognostic predictor in patients with congestive heart failure.

PubMed

Tsutamoto, T; Wada, A; Maeda, K; Mabuchi, N; Hayashi, M; Tsutsui, T; Ohnishi, M; Fujii, M; Matsumoto, T; Yamamoto, T; Takayama, T; Kinoshita, M

2001-12-01

Cardiac natriuretic peptides may induce apoptosis in myocytes; however, the relationship between plasma levels of cardiac natriuretic peptides and those of soluble Fas (sFas) and tumor necrosis factor (TNF)-alpha remains unknown in patients with congestive heart failure (CHF). We measured plasma levels of sFas and TNF-alpha and those of atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), norepinephrine, and endothelin 1 in 96 patients with CHF (ejection fraction < 45%). The patients were monitored for 3 years. Plasma levels of sFas and TNF-alpha increased with the severity of CHF. There was no significant correlation between sFas plasma levels and those of ANP and BNP. Cox proportional hazard analysis showed that high levels of sFas (P = .009) and BNP (P < .0001) and a low ejection fraction (P = .019) were independent significant prognostic predictors. There is no significant correlation between cardiac natriuretic peptide and sFas levels in plasma. Plasma sFas is a useful prognostic marker independent of neurohumoral factors, suggesting that immune activation and/or apoptosis play a significant role in the pathogenesis of CHF.

A novel unsaturated fatty acid hydratase toward C16 to C22 fatty acids from Lactobacillus acidophilus

PubMed Central

Hirata, Akiko; Kishino, Shigenobu; Park, Si-Bum; Takeuchi, Michiki; Kitamura, Nahoko; Ogawa, Jun

2015-01-01

Hydroxy FAs, one of the gut microbial metabolites of PUFAs, have attracted much attention because of their various bioactivities. The purpose of this study was to identify lactic acid bacteria with the ability to convert linoleic acid (LA) to hydroxy FAs. A screening process revealed that a gut bacterium, Lactobacillus acidophilus NTV001, converts LA mainly into 13-hydroxy-cis-9-octadecenoic acid and resulted in the identification of the hydratase responsible, fatty acid hydratase 1 (FA-HY1). Recombinant FA-HY1 was purified, and its enzymatic characteristics were investigated. FA-HY1 could convert not only C18 PUFAs but also C20 and C22 PUFAs. C18 PUFAs with a cis carbon-carbon double bond at the Δ12 position were converted into the corresponding 13-hydroxy FAs. Arachidonic acid and DHA were converted into the corresponding 15-hydroxy FA and 14-hydroxy FA, respectively. To the best of our knowledge, this is the first report of a bacterial FA hydratase that can convert C20 and C22 PUFAs into the corresponding hydroxy FAs. These novel hydroxy FAs produced by using FA-HY1 should contribute to elucidating the bioactivities of hydroxy FAs. PMID:25966711

Pentoxifylline attenuates cytokine stress and Fas system in syngeneic liver proteins induced experimental autoimmune hepatitis.

PubMed

Hendawy, Nevien

2017-08-01

Apoptosis is a hallmark in the pathogenesis of autoimmune hepatitis (AIH). Cytokine stresses and extrinsic apoptotic pathway have been implicated in this type of hepatic injury. Pentoxifylline plays an important role in controlling inflammation and apoptosis in different autoimmune diseases. To assess the protective effect of pentoxifylline for 30days against pro-inflammatory cytokines as tumor necrosis factor-alpha (TNF-α), interferon-gamma (INF-γ) and mediators of extrinsic apoptotic pathway involving TNF receptor 1 (TNFR1) and its ligand TNF-α and Fas receptor and its ligand (FasL) in experimental autoimmune hepatitis (EAH) model. EAH was induced by intraperitoneal injection of syngeneic liver antigen emulsified in complete Freund's adjuvant (CFA) in male C57BL/6 mice. Five groups of mice were used: two control groups; Control PBS group and Control CFA group, EAH group and two EAH+pentoxifylline treated groups in doses (100 or 200mg/kg/d, given by oral gavage). Serum transaminase, pro-inflammatory cytokines (TNF-α and interferon-γ) and hepatic caspase-8 and 3 activities were evaluated. Signs of autoimmune hepatitis were confirmed by liver histology. In addition, hepatic TNFR1, Fas and FasL mRNA expression were assayed. Serum transaminase levels and signs of AIH observed in EAH mice were significantly reduced by pentoxifylline. Upregulated serum TNF-α, IFN-γ, hepatic caspase-8 and 3 activities and TNFR1, Fas and FasL mRNA expression in liver tissues in EAH group were significantly downregulated by pentoxifylline. Pentoxifylline protects against syngeneic liver antigen induced hepatitis and associating apoptosis through attenuating the exaggerated cytokine release and extrinsic apoptotic pathway. Thus, this may represent a new therapeutic strategy for hepatitis. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Characterization of Calmodulin–Fas Death Domain Interaction: An Integrated Experimental and Computational Study

PubMed Central

2015-01-01

The Fas death receptor-activated death-inducing signaling complex (DISC) regulates apoptosis in many normal and cancer cells. Qualitative biochemical experiments demonstrate that calmodulin (CaM) binds to the death domain of Fas. The interaction between CaM and Fas regulates Fas-mediated DISC formation. A quantitative understanding of the interaction between CaM and Fas is important for the optimal design of antagonists for CaM or Fas to regulate the CaM–Fas interaction, thus modulating Fas-mediated DISC formation and apoptosis. The V254N mutation of the Fas death domain (Fas DD) is analogous to an identified mutant allele of Fas in lpr-cg mice that have a deficiency in Fas-mediated apoptosis. In this study, the interactions of CaM with the Fas DD wild type (Fas DD WT) and with the Fas DD V254N mutant were characterized using isothermal titration calorimetry (ITC), circular dichroism spectroscopy (CD), and molecular dynamics (MD) simulations. ITC results reveal an endothermic binding characteristic and an entropy-driven interaction of CaM with Fas DD WT or with Fas DD V254N. The Fas DD V254N mutation decreased the association constant (Ka) for CaM–Fas DD binding from (1.79 ± 0.20) × 106 to (0.88 ± 0.14) × 106 M–1 and slightly increased a standard state Gibbs free energy (ΔG°) for CaM–Fas DD binding from −8.87 ± 0.07 to −8.43 ± 0.10 kcal/mol. CD secondary structure analysis and MD simulation results did not show significant secondary structural changes of the Fas DD caused by the V254N mutation. The conformational and dynamical motion analyses, the analyses of hydrogen bond formation within the CaM binding region, the contact numbers of each residue, and the electrostatic potential for the CaM binding region based on MD simulations demonstrated changes caused by the Fas DD V254N mutation. These changes caused by the Fas DD V254N mutation could affect the van der Waals interactions and electrostatic interactions between CaM and Fas DD, thereby

FasL Mediates T-Cell Eradication of Tumor Cells Presenting Low Levels of Antigens | Center for Cancer Research

Cancer.gov

One approach to cancer immunotherapy, as opposed to therapeutic vaccination, is the transfusion of large numbers of tumor-specific killer T cells (cytotoxic T cells or CTLs) into patients. The body’s own defense killer T cells are a subgroup of T lymphocytes (a type of white blood cells) that are capable of inducing death in tumor cells. CTLs can cause the death of target cells either by releasing granules containing toxic molecules including perforin, or by producing a membrane protein called Fas ligand (FasL) which on interaction with the tumor cell results in cell death.

Low Doses of Exogenous Interferon-γ Attenuated Airway Inflammation Through Enhancing Fas/FasL-Induced CD4+ T Cell Apoptosis in a Mouse Asthma Model

PubMed Central

Yao, Yinan; Lu, Shan; Lu, Guohua

2012-01-01

To investigate whether low doses of exogenous interferon (IFN)-γ attenuate airway inflammation, and the underlying mechanisms, in asthma. C57BL/6 mice (n=42), after intraperitoneal ovalbumin (OVA) sensitization on day 0 and day 12, were challenged with OVA aerosol for 6 consecutive days. Different doses of IFN-γ were then administered intraperitoneally 5 min before each inhalation during OVA challenge. Airway hyperresponsiveness, airway inflammatory cells, cytokine profiles, and Fas/FasL expression on CD4+ T cells were evaluated in an asthma model. The effect of various IFN-γ doses on Fas/FasL expression and CD4+ T cell apoptosis were assessed in vitro. We demonstrated that low doses of IFN-γ reduced pulmonary infiltration of inflammatory cells, Th2 cytokine production, and goblet cells hyperplasia (P<0.05), while high doses of endogenous IFN-γ had almost no effect. We also found that low doses of IFN-γ relocated Fas/FasL to the CD4+ T cell surface in the asthma model (P<0.05) and increased FasL-induced apoptosis in vitro (P<0.05). Furthermore, treatment with MFL-3, an anti-FasL antibody, partially abolished the anti- inflammatory properties of IFN-γ in the airway rather than affecting the Th1/Th2 balance. This research has revealed an alternative mechanism in asthma that involves low doses of IFN-γ, which attenuate airway inflammation through enhancing Fas/FasL-induced CD4+ T cell apoptosis. PMID:22994871

FAS grafted superhydrophobic ceramic membrane

NASA Astrophysics Data System (ADS)

Lu, Jun; Yu, Yun; Zhou, Jianer; Song, Lixin; Hu, Xingfang; Larbot, Andre

2009-08-01

The hydrophobic properties of γ-Al 2O 3 membrane have been obtained by grafting fluoroalkylsilane (FAS) on the surface of the membrane. The following grafting parameters were studied: the eroding time of the original membrane, the grafting time, the concentration of FAS solution and the multiplicity of grafting. Hydrophobicity of the membranes was characterized by contact angle (CA) measurement. The thermogravimetric analysis (TGA) was used to investigate the weight loss process (25-800 °C) of the fluoroalkylsilane grafted on Al 2O 3 powders under different grafting conditions. The morphologies of the membranes modified under different parameters were examined by field emission scanning electron microscopy (FE-SEM) and the surface roughness (Ra) was measured using white light interferometers. A needle-like structure was observed on the membrane surface after modification, which causes the change of Ra. On the results above, we speculated a model to describe the reaction between FAS and γ-Al 2O 3 membrane surface as well as the formed surface morphology.

Increased expression of Fas receptor and Fas ligand in the culture of the peripheral blood mononuclear cells stimulated with Borrelia burgdorferi sensu lato.

PubMed

Grygorczuk, Sambor; Osada, Joanna; Moniuszko, Anna; Świerzbińska, Renata; Kondrusik, Maciej; Zajkowska, Joanna; Dunaj, Justyna; Dąbrowska, Milena; Pancewicz, Sławomir

2015-03-01

Apoptosis of the lymphocytes plays an essential role in the regulation of inflammatory/immune responses and its abnormalities may contribute to a chronic infection, persistent inflammation and autoimmunity. Its role in the pathogenesis of the late Lyme borreliosis manifestations has not been studied so far. We have measured Th lymphocyte apoptosis rate, membrane expression of pro-apoptotic Fas receptor, and supernatant concentrations of selected soluble pro- and anti-apoptotic mediators in cultures of peripheral blood mononuclear cells from 16 patients with disseminated Lyme borreliosis (6 with osteoarticular symptoms, 7 with neuroborreliosis and 3 with acrodermatitis chronica atrophicans) and 8 healthy controls. The cultures stimulated for 48h with live Borrelia burgdorferi sensu stricto, B. garinii or B. afzelii spirochetes. Fraction of the apoptotic Th (CD3+CD4+) lymphocytes and expression of Fas in this cell population was measured cytometrically and concentrations of soluble Fas, soluble Fas ligand, IL-10, IL-12 and TGF-β in culture supernatant with ELISA assays. The expression of IL-10, soluble and membrane Fas and soluble Fas ligand was increased under stimulation and higher in the presence of B. burgdorferi sensu stricto than the other species. Apoptosis rate was not affected. There was no difference between Lyme borreliosis patients and controls. IL-10 concentration correlated negatively with the membrane Fas expression and apoptosis under stimulation with B. afzelii and B. garinii. Expression of Fas/FasL system is up-regulated under stimulation with B. burgdorferi, but without corresponding increase in lymphocyte apoptosis. Variable responses observed with different B. burgdorferi species may reflect differences in the pathogenesis of the infection in vivo. Copyright © 2014 Elsevier GmbH. All rights reserved.

Significant role of Fas ligand-binding but defective Fas receptor (CD95) in lymph node hyperplasia composed of abnormal double-negative T cells

PubMed Central

Matsuzawa, Akio; Shimizu, Motomu; Takeda, Yasutaka; Nagase, Hisashi; Sayama, Kazutoshi; Kimura, Mikio

2002-01-01

The functional differences between two mutations of the Fas (CD95) locus, Faslpr (lpr) and Faslprcg (lprcg), were investigated using bone marrow (BM) transplantation on the C3H mouse background. Both lpr/lpr and lprcg/lprcg BM transferred caused lymph node (LN) hyperplasia in lpr/+ and lprcg/+ recipients, although it was clearly smaller than that in lpr/lpr and lprcg/lprcg recipients of lpr/lpr and lprcg/lprcg BM. In addition, both BM induced significantly larger LN hyperplasia in lprcg/+ than lpr/+ recipients. Appearance of CD4− CD8−[double negative (DN)] T cells in the periphery is the most consistent phenotype of Fas mutations. Importantly, the proportion of DN T cells was higher in larger LN hyperplasia in the order of lpr/+, lprcg/+ and lpr/lpr or lprcg/lprcg recipients. On the other hand, both lpr/lpr and lprcg/lprcg BM transferred into wild-type (+/+) mice caused marked LN atrophy. The former, but not the latter, induced wasting syndrome. Faslg1d (gld)-homozygous lpr/lpr BM transferred into +/+ mice elicited LN hyperplasia of the same extent as that in lpr/lpr mice transferred with lpr/lpr BM, but not wasting syndrome. Taken together with the fact that DN T cells massively express Fas ligand (FasL), this study implied that FasL overexpressed on DN cells may be involved in the accumulation of DN T cells in LN, LN atrophy and wasting syndrome, and that lprcg Fas, which can bind to Fas ligand but not transduce apoptosis signal into cells, may modulate these pathological conditions by interfering with the binding of FasL to Fas. PMID:12153509

Reproductive corticotropin releasing hormone, implantation, and fetal immunotolerance.

PubMed

Kalantaridou, Sophia N; Zoumakis, Emmanouil; Weil, Stacie; Lavasidis, Lazaros G; Chrousos, George P; Makrigiannakis, Antonis

2007-01-01

The fundamental process of implantation involves a series of steps leading to effective cross-talk between invasive trophoblast cells and the maternal endometrium. The molecular interactions at the embryo-maternal interface during the time of blastocyst adhesion and subsequent invasion are not fully understood. Embryonic trophoblast and maternal decidual cells produce corticotropin-releasing hormone (CRH) and express Fas ligand (FasL), a proapoptotic cytokine. Fas and its ligand are pivotal in the regulation of immune tolerance. Trophoblast and decidual CRH play crucial roles in implantation, as well as in the anti-rejection process that protects the fetus from the maternal immune system, primarily by killing activated T cells through Fas-FasL interaction. The potential use of CRH antagonists is presently under intense investigation. CRH antagonists have been used experimentally to elucidate the role of CRH in blastocyst implantation and invasion, early fetal immunotolerance, and premature labor.

Abnormal structural luteolysis in ovaries of the senescence accelerated mouse (SAM): expression of Fas ligand/Fas-mediated apoptosis signaling molecules in luteal cells.

PubMed

Kiso, Minako; Manabe, Noboru; Komatsu, Kohji; Shimabe, Munetake; Miyamoto, Hajime

2003-12-01

Senescence accelerated mouse-prone (SAMP) mice with a shortened life span show accelerated changes in many of the signs of aging and a shorter reproductive life span than SAM-resistant (SAMR) controls. We previously showed that functional regression (progesterone dissimilation) occurs in abnormally accumulated luteal bodies (aaLBs) of SAMP mice, but structural regression of luteal cells in aaLB is inhibited. A deficiency of luteal cell apoptosis causes the abnormal accumulation of LBs in SAMP ovaries. In the present study, to show the abnormality of Fas ligand (FasL)/Fas-mediated apoptosis signal transducing factors in the aaLBs of the SAMP ovaries, we assessed the changes in the expression of FasL, Fas, caspase-8 and caspase-3 mRNAs by reverse transcription-polymerase chain reaction, and in the expression and localization of FasL, Fas and activated caspase-3 proteins by Western blotting and immunohistochemistry, respectively, during the estrus cycle/luteolysis. These mRNAs and proteins were expressed in normal LBs of both SAMP and SAMR ovaries, but not at all or only in trace amounts in aaLBs of SAMP, indicating that structural regression is inhibited by blockage of the expression of these transducing factors in luteal cells of aaLBs in SAMP mice.

Effects of apigenin on the expression levels of B-cell lymphoma-2, Fas and Fas ligand in renal ischemia-reperfusion injury in rats.

PubMed

Liu, Yang; Liu, Xiuheng; Wang, Lei; Du, Yang; Chen, Zhiyuan; Chen, Hui; Guo, Jia; Weng, Xiaodong; Wang, Xiao; Wang, Ming; Wang, Zhishun

2017-12-01

The aim of the present study was to investigate the effect and possible mechanism of apigenin on renal ischemia-reperfusion (I/R) injury in rats, as well as in in vitro experiments. In total, 36 rats were subjected to 45 min of renal ischemia, with or without treatment prior to ischemia with different concentrations of apigenin (2, 10 and 50 mg/kg) administered intravenously. All rats were sacrificed at 24 h after I/R injury. The serum creatinine (Cr) and blood urea nitrogen (BUN) levels were analyzed, and histological examination was conducted. In addition, the expression levels of B-cell lymphoma 2 (Bcl-2) and Fas/Fas ligand (FasL) were detected by immunohistochemistry, reverse transcription-quantitative polymerase chain reaction and western blot analysis. For in vitro experiments, the NRK-52E cell line was employed. The viability, apoptosis and expression levels of Fas, FasL and Bcl-2 were examined in the culture of NRK-52E cells following the I/R. The results indicated that apigenin significantly decreased the levels of serum Cr and BUN induced by renal I/R, demonstrating an improvement in renal function. The histological evidence of renal damage associated with I/R was also mitigated by apigenin in vivo . Furthermore, apigenin increased the cell viability and decreased cell apoptosis in the culture of NRK52E after I/R in vitro . Compared with the I/R group, the expression of Bcl-2 was upregulated and the expression levels of Fas and FasL were downregulated by apigenin at the mRNA and protein levels in vivo and in vitro . In conclusion, apigenin appeared to increase the expression of Bcl-2 and reduce Fas/FasL expression in renal I/R injury, providing evident protection against renal I/R injury in rats.

Effects of apigenin on the expression levels of B-cell lymphoma-2, Fas and Fas ligand in renal ischemia-reperfusion injury in rats

PubMed Central

Liu, Yang; Liu, Xiuheng; Wang, Lei; Du, Yang; Chen, Zhiyuan; Chen, Hui; Guo, Jia; Weng, Xiaodong; Wang, Xiao; Wang, Ming; Wang, Zhishun

2017-01-01

The aim of the present study was to investigate the effect and possible mechanism of apigenin on renal ischemia-reperfusion (I/R) injury in rats, as well as in in vitro experiments. In total, 36 rats were subjected to 45 min of renal ischemia, with or without treatment prior to ischemia with different concentrations of apigenin (2, 10 and 50 mg/kg) administered intravenously. All rats were sacrificed at 24 h after I/R injury. The serum creatinine (Cr) and blood urea nitrogen (BUN) levels were analyzed, and histological examination was conducted. In addition, the expression levels of B-cell lymphoma 2 (Bcl-2) and Fas/Fas ligand (FasL) were detected by immunohistochemistry, reverse transcription-quantitative polymerase chain reaction and western blot analysis. For in vitro experiments, the NRK-52E cell line was employed. The viability, apoptosis and expression levels of Fas, FasL and Bcl-2 were examined in the culture of NRK-52E cells following the I/R. The results indicated that apigenin significantly decreased the levels of serum Cr and BUN induced by renal I/R, demonstrating an improvement in renal function. The histological evidence of renal damage associated with I/R was also mitigated by apigenin in vivo. Furthermore, apigenin increased the cell viability and decreased cell apoptosis in the culture of NRK52E after I/R in vitro. Compared with the I/R group, the expression of Bcl-2 was upregulated and the expression levels of Fas and FasL were downregulated by apigenin at the mRNA and protein levels in vivo and in vitro. In conclusion, apigenin appeared to increase the expression of Bcl-2 and reduce Fas/FasL expression in renal I/R injury, providing evident protection against renal I/R injury in rats. PMID:29285062

Iron Release from Soybean Seed Ferritin Induced by Cinnamic Acid Derivatives.

PubMed

Sha, Xuejiao; Chen, Hai; Zhang, Jingsheng; Zhao, Guanghua

2018-05-04

Plant ferritin represents a novel class of iron supplement, which widely co-exists with phenolic acids in a plant diet. However, there are few reports on the effect of these phenolic acids on function of ferritin. In this study, we demonstrated that cinnamic acid derivatives, as widely occurring phenolic acids, can induce iron release from holo soybean seed ferritin (SSF) in a structure-dependent manner. The ability of the iron release from SSF by five cinnamic acids follows the sequence of Cinnamic acid > Chlorogenic acid > Ferulic acid > p -Coumaric acid > Trans -Cinnamic acid. Fluorescence titration in conjunction with dialysis results showed that all of these five compounds have a similar, weak ability to bind with protein, suggesting that their protein-binding ability is not related to their iron release activity. In contrast, both Fe 2+ -chelating activity and reducibility of these cinnamic acid derivatives are in good agreement with their ability to induce iron release from ferritin. These studies indicate that cinnamic acid and its derivatives could have a negative effect on iron stability of holo soybean seed ferritin in diet, and the Fe 2+ -chelating activity and reducibility of cinnamic acid and its derivatives have strong relations to the iron release of soybean seed ferritin.

Stimulation of Fas/FasL-mediated apoptosis by luteolin through enhancement of histone H3 acetylation and c-Jun activation in HL-60 leukemia cells.

PubMed

Wang, Shih-Wei; Chen, Yun-Ru; Chow, Jyh-Ming; Chien, Ming-Hsien; Yang, Shun-Fa; Wen, Yu-Ching; Lee, Wei-Jiunn; Tseng, Tsui-Hwa

2018-07-01

Luteolin (3',4',5,7-tetrahydroxyflavone), which exists in fruits, vegetables, and medicinal herbs, is used in Chinese traditional medicine for treating various diseases, such as hypertension, inflammatory disorders, and cancer. However, the gene-regulatory role of luteolin in cancer prevention and therapy has not been clarified. Herein, we demonstrated that treatment with luteolin resulted in a significant decrease in the viability of human leukemia cells. In the present study, by evaluating fragmentation of DNA and poly (ADP-ribose) polymerase (PARP), we found that luteolin was able to induce PARP cleavage and nuclear fragmentation as well as an increase in the sub-G 0 /G 1 fraction. In addition, luteolin also induced Fas and Fas ligand (FasL) expressions and subsequent activation of caspases-8 and -3, which can trigger the extrinsic apoptosis pathway, while knocking down Fas-associated protein with death domain (FADD) prevented luteolin-induced PARP cleavage. Immunoblot and chromatin immunoprecipitation (ChIP) analyses revealed that luteolin increased acetylation of histone H3, which is involved in the upregulation of Fas and FasL. Moreover, both the extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK) pathways are involved in luteolin-induced histone H3 acetylation. Finally, luteolin also activated the c-Jun signaling pathway, which contributes to FasL, but not Fas, gene expression and downregulation of c-Jun expression by small interfering RNA transfection which resulted in a significant decrease in luteolin-induced PARP cleavage. Thus, our results demonstrate that luteolin induced apoptosis of HL-60 cells, and this was associated with c-Jun activation and histone H3 acetylation-mediated Fas/FasL expressions. © 2018 Wiley Periodicals, Inc.

Mutation in the Fas Pathway Impairs CD8+ T Cell Memory1

PubMed Central

Dudani, Renu; Russell, Marsha; van Faassen, Henk; Krishnan, Lakshmi; Sad, Subash

2014-01-01

Fas death pathway is important for lymphocyte homeostasis, but the role of Fas pathway in T cell memory development is not clear. We show that whereas the expansion and contraction of CD8+ T cell response against Listeria monocytogenes were similar for wild-type (WT) and Fas ligand (FasL) mutant mice, the majority of memory CD8+ T cells in FasL mutant mice displayed an effector memory phenotype in the long-term in comparison with the mainly central memory phenotype displayed by memory CD8+ T cells in WT mice. Memory CD8+ T cells in FasL mutant mice expressed reduced levels of IFN-γ and displayed poor homeostatic and Ag-induced proliferation. Impairment in CD8+ T cell memory in FasL mutant hosts was not due to defective programming or the expression of mutant FasL on CD8+ T cells, but was caused by perturbed cytokine environment in FasL mutant mice. Although adoptively transferred WT memory CD8+ T cells mediated protection against L. monocytogenes in either the WT or FasL mutant hosts, FasL mutant memory CD8+ T cells failed to mediate protection even in WT hosts. Thus, in individuals with mutation in Fas pathway, impairment in the function of the memory CD8+ T cells may increase their susceptibility to recurrent/latent infections. PMID:18292515

Acid-base properties of humic and fulvic acids formed during composting.

PubMed

Plaza, César; Senesi, Nicola; Polo, Alfredo; Brunetti, Gennaro

2005-09-15

The soil acid-base buffering capacity and the biological availability, mobilization, and transport of macro- and micronutrients, toxic metal ions, and xenobiotic organic cations in soil are strongly influenced by the acid-base properties of humic substances, of which humic and fulvic acids are the major fractions. For these reasons, the proton binding behavior of the humic acid-like (HA) and fulvic acid-like (FA) fractions contained in a compost are believed to be instrumental in its successful performance in soil. In this work, the acid-base properties of the HAs and FAs isolated from a mixture of the sludge residue obtained from olive oil mill wastewater (OMW) evaporated in an open-air pond and tree cuttings (TC) at different stages of composting were investigated by a current potentiometric titration method and the nonideal competitive adsorption (NICA)-Donnan model. The NICA-Donnan model provided an excellent description of the acid-base titration data, and pointed out substantial differences in site density and proton-binding affinity between the HAs and FAs examined. With respect to FAs, HAs were characterized by a smaller content of carboxylic- and phenolic-type groups and their larger affinities for proton binding. Further, HAs featured a greater heterogeneity in carboxylic-type groups than FAs. The composting process increased the content and decreased the proton affinity of carboxylic- and phenolic-type groups of HAs and FAs, and increased the heterogeneity of phenolic-type groups of HAs. As a whole, these effects indicated that the composting process could produce HA and FA fractions with greater cation binding capacities. These results suggest that composting of organic materials improves their agronomic and environmental value by increasing their potential to retain and exchange macro- and micronutrients, and to reduce the bioavailability of organic and inorganic pollutants.

The role of Fas ligand and transforming growth factor beta in tumor progression: molecular mechanisms of immune privilege via Fas-mediated apoptosis and potential targets for cancer therapy.

PubMed

Kim, Ryungsa; Emi, Manabu; Tanabe, Kazuaki; Uchida, Yoko; Toge, Tetsuya

2004-06-01

Despite the fact that expression of Fas ligand (FasL) in cytotoxic T lymphocytes (CTLs) and in natural killer (NK) cells plays an important role in Fas-mediated tumor killing, During tumor progression FasL-expressing tumor cells are involved in counterattacking to kill tumor-infiltrating lymphocytes (TILs). Soluble FasL levels also increase with tumor progression in solid tumors, and this increase inhibits Fas-mediated tumor killing by CTLs and NK cells. The increased expression of FasL in tumor cells is associated with decreased expression of Fas; and the promoter region of the FASL gene is regulated by transcription factors, such as neuronal factor kappaB (NF-kappaB) and AP-1, in the tumor microenvironment. Although the ratio of FasL expression to Fas expression in tumor cells is not strongly related to the induction of apoptosis in TILs, increased expression of FasL is associated with decreased Fas levels in tumor cells that can escape immune surveillance and facilitate tumor progression and metastasis. Transforming growth factor beta (TGF-beta) is a potent growth inhibitor and has tumor-suppressing activity in the early phases of carcinogenesis. During subsequent tumor progression, the increased secretion of TGF-beta by both tumor cells and, in a paracrine fashion, stromal cells, is involved in the enhancement of tumor invasion and metastasis accompanied by immunosuppression. Herein, the authors review the clinical significance of FasL and TGF-beta expression patterns as features of immune privilege accompanying tumor progression in the tumor microenvironment. Potential strategies for identifying which molecules can serve as targets for effective antitumor therapy also are discussed. Copyright 2004 American Cancer Society.

Fluoride reduced the immune privileged function of mouse Sertoli cells via the regulation of Fas/FasL system.

PubMed

Sun, Zilong; Nie, Qingli; Zhang, Lianjie; Niu, Ruiyan; Wang, Jundong; Wang, Shaolin

2017-02-01

Previous investigations have demonstrated the adverse impacts of fluoride on Sertoli cells (SCs), such as oxidative stress and apoptosis. SCs are the crucial cellular components that can create the immune privileged environment in testis. However, the effect of fluoride on SCs immune privilege is unknown. In this study, mouse SCs were exposed to sodium fluoride with varying concentrations of 10 -5 , 10 -4 , and 10 -3  mol/L to establish the model of fluoride-treated SCs (F-SCs) in vitro. After 48 h of incubation, F-SCs were transplanted underneath the kidney capsule of mice for 21 days, or cocultured with spleen lymphocytes for another 48 h. Immunohistochemical analysis of GATA4 in SCs grafts underneath kidney capsule presented less SCs distribution and obvious immune cell infiltration in F-SCs groups. In addition, the levels of FasL protein and mRNA in non-cocultured F-SCs decreased with the increase of fluoride concentration. When cocultured with F-SCs, lymphocytes presented significantly high cell viability and low apoptosis in F-SCs groups. Protein and mRNA expressions of FasL in cocultured F-SCs and Fas in lymphocytes were reduced, and the caspase 8 and caspase 3 mRNA levels were also decreased in fluoride groups in a dose-dependent manner. These findings indicated that fluoride influenced the testicular immune privilege through disturbing the Fas/FasL system. Copyright © 2016 Elsevier Ltd. All rights reserved.

Canine bombesin-like gastrin releasing peptides stimulate gastrin release and acid secretion in the dog.

PubMed Central

Bunnett, N W; Clark, B; Debas, H T; Del Milton, R C; Kovacs, T O; Orloff, M S; Pappas, T N; Reeve, J R; Rivier, J E; Walsh, J H

1985-01-01

The synthetic mammalian bombesin-like peptides, canine gastrin releasing peptide 27, 23 and 10, and porcine gastrin releasing peptide 27 were compared with amphibian bombesin 14 and 10 during intravenous infusions into six conscious dogs with chronic gastric cannulae. Gastrin and gastrin releasing peptide were measured in peripherally sampled venous blood by radioimmunoassay and gastric acid secretions were collected. All forms of gastrin releasing peptide stimulated gastrin release and gastric acid secretion in a dose-dependent manner. The larger canine and porcine peptides were more potent than the decapeptide. Bombesin 14 was more potent than bombesin 10. A rise in the venous concentration of immunoreactive gastrin releasing peptide of only 20 fmol ml-1 stimulated gastrin release to about 50% of maximal. Gastrin releasing peptide 10 was cleared from the circulation three times faster than the larger forms and this may account for the apparent differences in potency. PMID:3839849

Crosstalk between Fas and JNK determines lymphocyte apoptosis after ionizing radiation.

PubMed

Praveen, Koganti; Saxena, Nandita

2013-06-01

Radiation simultaneously activate Fas and JNK pathway in lymphocytes but their precise interaction is not clearly understood. Activation of Fas pathway is required for radiation induced apoptosis, however induction of JNK pathway may or may not contribute in apoptosis. Here we report that Fas, Fas associated death domain and total JNK are activated in a dose- and time-dependent radiation exposure. A biphasic pattern of phospho-JNK was found at lower doses (1 and 2 Gy), however at higher doses of radiation phospho-JNK was continuously activated. Interestingly, Fas ligand expression remained biphasic at all the doses of radiation. Our results suggest that the Fas pathway is the major player in radiation-induced apoptosis, with JNK playing a contributory role. We also observed that Fas ligand expression by radiation is dependent on JNK activation. We also propose that radiation activates JNK pathway, but sustained activation is required for maximal induction of apoptosis at later times. Our findings define a mechanism for crosstalk between JNK and Fas pathway in radiation-induced apoptosis, which may lead to the development of new therapeutic strategies.

An engineered fatty acid synthase combined with a carboxylic acid reductase enables de novo production of 1-octanol in Saccharomyces cerevisiae.

PubMed

Henritzi, Sandra; Fischer, Manuel; Grininger, Martin; Oreb, Mislav; Boles, Eckhard

2018-01-01

The ideal biofuel should not only be a regenerative fuel from renewable feedstocks, but should also be compatible with the existing fuel distribution infrastructure and with normal car engines. As the so-called drop-in biofuel, the fatty alcohol 1-octanol has been described as a valuable substitute for diesel and jet fuels and has already been produced fermentatively from sugars in small amounts with engineered bacteria via reduction of thioesterase-mediated premature release of octanoic acid from fatty acid synthase or via a reversal of the β-oxidation pathway. The previously engineered short-chain acyl-CoA producing yeast Fas1 R1834K /Fas2 fatty acid synthase variant was expressed together with carboxylic acid reductase from Mycobacterium marinum and phosphopantetheinyl transferase Sfp from Bacillus subtilis in a Saccharomyces cerevisiae Δfas1 Δfas2 Δfaa2 mutant strain. With the involvement of endogenous thioesterases, alcohol dehydrogenases, and aldehyde reductases, the synthesized octanoyl-CoA was converted to 1-octanol up to a titer of 26.0 mg L -1 in a 72-h fermentation. The additional accumulation of 90 mg L -1 octanoic acid in the medium indicated a bottleneck in 1-octanol production. When octanoic acid was supplied externally to the yeast cells, it could be efficiently converted to 1-octanol indicating that re-uptake of octanoic acid across the plasma membrane is not limiting. Additional overexpression of aldehyde reductase Ahr from Escherichia coli nearly completely prevented accumulation of octanoic acid and increased 1-octanol titers up to 49.5 mg L -1 . However, in growth tests concentrations even lower than 50.0 mg L -1 turned out to be inhibitory to yeast growth. In situ extraction in a two-phase fermentation with dodecane as second phase did not improve growth, indicating that 1-octanol acts inhibitive before secretion. Furthermore, 1-octanol production was even reduced, which results from extraction of the intermediate octanoic acid to

FAS promoter polymorphisms and serum sFas level are associated with increased risk of nerve damage in Bangladeshi patients with Guillain-Barré syndrome.

PubMed

Islam, Zhahirul; Jahan, Israt; Ahammad, Rijwan U; Shahnaij, Mohammad; Nahar, Shamsun; Mohammad, Quazi D

2018-01-01

Guillain-Barré syndrome (GBS) is an autoimmune disorder of the peripheral nervous system triggered by molecular mimicry between pathogen lipopolysaccharides and host nerve gangliosides. Polymorphisms in the Fas receptor (FAS) and Fas ligand (FASL) genes may potentially alter the elimination of autoreactive immune cells and affect disease susceptibility or disease severity in GBS. We detected single nucleotide polymorphisms (SNPs) in FAS (-1377G/A and -670A/G) and FASL (-843C/T) in a prospective cohort of 300 patients with GBS and 300 healthy controls from the Bangladeshi population. Genotype distributions were not significantly different between patients with GBS and healthy controls. The FAS -670 AG heterozygous (P = 0.0005, OR = 2.5, 95% CI = 1.5-4.2) and GG homozygous (P = 0.0048, OR = 2.6, 95% CI = 1.3-5.0) genotypes were more common in patients with anti-GM1 antibodies than patients without anti-GM1 antibodies. The FAS -670 G allele was more prevalent in anti-GM1 antibody-positive than -negative patients (P = 0.0002, OR = 1.9, 95% CI = 1.4-2.7) and also in patients with the axonal subtype than demyelinating subtype (P < 0.0001, OR = 4.8, 95% CI = 2.3-10.1). The 1377G/-670G GG haplotype was significantly associated with the axonal subtype (P < 0.0001) and anti-ganglioside antibody-positivity (P = 0.0008) in GBS. Serum sFas (237.5 pg/mL vs. 159.5 pg/mL; P < 0.0001) and sFasL (225.1 pg/mL vs. 183.4 pg/mL; P = 0.0069) were elevated in patients with GBS compared to healthy controls, and among patients with high serum sFas was associated with severe GBS (P = 0.0406). In conclusion, this study indicates FAS-FASL promoter SNPs may promote the production of cross-reactive anti-ganglioside antibodies in GBS.

Osthole induces human nasopharyngeal cancer cells apoptosis through Fas-Fas ligand and mitochondrial pathway.

PubMed

Liu, Pei-Ying; Chang, Dun-Cheng; Lo, Yu-Sheng; Hsi, Yi-Ting; Lin, Chia-Chieh; Chuang, Yi-Ching; Lin, Shu-Hui; Hsieh, Ming-Ju; Chen, Mu-Kuan

2018-04-01

Nasopharyngeal carcinoma (NPC) is endemic in Southern China and Southeast Asia. The present study investigated the activity of osthole in suppressing NPC along with the underlying mechanism. Cell growth inhibition was measured using the MTT assay. Apoptosis was detected through 4',6-diamidino-2-phenylindole staining and flow cytometry. Western blotting was used to identify the signaling pathway. Osthole markedly inhibited cell proliferation and induced apoptosis in the NPC cell line. Western blotting results revealed the increased activation of caspases 3, 8, and 9 and poly (ADP-ribose) polymerase. Osthole treatment significantly reduced the expression of the antiapoptotic protein Bcl-2 and increased the expression of the proapoptotic proteins Bax, Bak, BimL, BimS, and t-Bid. Osthole treatment also increased the expression of Fas, FADD, TNF-R1, TNF-R2, DcR2, RIP, and DR5. In addition, osthole treatment significantly increased the expression levels of phosphorylated ERK1/2 and JNK1/2. These results suggested that osthole exerts cytotoxic effects on NPC cell lines mainly through apoptosis mediated by the Fas-Fas ligand and mitochondrial pathway. Osthole could be a potential anticancer agent for NPC. © 2018 Wiley Periodicals, Inc.

Fatty acids linked to cardiovascular mortality are associated with risk factors

PubMed Central

Ebbesson, Sven O. E.; Voruganti, Venkata S.; Higgins, Paul B.; Fabsitz, Richard R.; Ebbesson, Lars O.; Laston, Sandra; Harris, William S.; Kennish, John; Umans, Benjamin D.; Wang, Hong; Devereux, Richard B.; Okin, Peter M.; Weissman, Neil J.; MacCluer, Jean W.; Umans, Jason G.; Howard, Barbara V.

2015-01-01

Background Although saturated fatty acids (FAs) have been linked to cardiovascular mortality, it is not clear whether this outcome is attributable solely to their effects on low-density lipoprotein cholesterol (LDL-C) or whether other risk factors are also associated with FAs. The Western Alaskan Native population, with its rapidly changing lifestyles, shift in diet from unsaturated to saturated fatty acids and dramatic increase in cardiovascular disease (CVD), presents an opportunity to elucidate any associations between specific FAs and known CVD risk factors. Objective We tested the hypothesis that the specific FAs previously identified as related to CVD mortality are also associated with individual CVD risk factors. Methods In this community-based, cross-sectional study, relative proportions of FAs in plasma and red blood cell membranes were compared with CVD risk factors in a sample of 758 men and women aged ≥35 years. Linear regression analyses were used to analyze relations between specific FAs and CVD risk factors (LDL-C, high-density lipoprotein cholesterol, triglycerides, C-reactive protein, systolic blood pressure, diastolic blood pressure, heart rate, body mass index, fasting glucose and fasting insulin, 2-hour glucose and 2-hour insulin). Results The specific saturated FAs previously identified as related to CVD mortality, the palmitic and myristic acids, were adversely associated with most CVD risk factors, whereas unsaturated linoleic acid (18:2n-6) and the marine n-3 FAs were not associated or were beneficially associated with CVD risk factors. Conclusions The results suggest that CVD risk factors are more extensively affected by individual FAs than hitherto recognized, and that risk for CVD, MI and stroke can be reduced by reducing the intake of palmitate, myristic acid and simple carbohydrates and improved by greater intake of linoleic acid and marine n-3 FAs. PMID:26274054

Temporal dynamics of amino and fatty acid composition in the razor clam Ensis siliqua (Mollusca: Bivalvia)

NASA Astrophysics Data System (ADS)

Baptista, Miguel; Repolho, Tiago; Maulvault, Ana Luísa; Lopes, Vanessa M.; Narciso, Luis; Marques, António; Bandarra, Narcisa; Rosa, Rui

2014-12-01

Few studies have been conducted on the temporal dynamics of both amino acid (AA) and fatty acid (FA) profiles in marine bivalves. We investigated the seasonal variation of these compounds in the pod razor clam Ensis siliqua in relation to food availability, salinity, water temperature and reproductive cycle. AA content varied between 46.94 and 54.67 % dry weight (DW), and the AAs found in greater quantity were glutamic acid, glycine and aspartic acid. FA content varied between 34.02 and 87.94 mg g-1 DW and the FAs found in greater quantity were 16:0 and 22:6 n-3. Seasonal trends were observed for AAs and FAs. FAs increased with gametogenesis and decreased with spawning while AA content increased throughout spawning. The effect of increasing temperature and high food availability during the spawning season masked the loss of AAs resulting from gamete release. Still, a comparatively greater increase in the contents of glutamic acid and leucine with spawning indicate their possible involvement in a post-spawning gonad recovery mechanism. A post-spawning decrease in 14:0, 16:0, 16:1 n-7, 18:1 n-7 and 18:1 n-9 is indicative of the importance of these FAs in bivalve eggs. An increase in 18:3 n-3, 18:4 n-3, 20:1 n-9 and 20:2 n-6 during gametogenesis suggests their involvement in oocyte maturation. The FA 22:4 n-6, while increasing with spawning, appears to play a role in post-spawning gonad recovery. Salinity did not have an effect on the AA composition. None of the environmental parameters measured had an effect on FA composition.

Regulation of fibroblast Fas expression by soluble and mechanical pro-fibrotic stimuli.

PubMed

Dodi, Amos E; Ajayi, Iyabode O; Chang, Christine; Beard, Meghan; Ashley, Shanna L; Huang, Steven K; Thannickal, Victor J; Tschumperlin, Daniel J; Sisson, Thomas H; Horowitz, Jeffrey C

2018-05-10

Fibroblast apoptosis is a critical component of normal repair and the acquisition of an apoptosis-resistant phenotype contributes to the pathogenesis of fibrotic repair. Fibroblasts from fibrotic lungs of humans and mice demonstrate resistance to apoptosis induced by Fas-ligand and prior studies have shown that susceptibility to apoptosis is enhanced when Fas (CD95) expression is increased in these cells. Moreover, prior work shows that Fas expression in fibrotic lung fibroblasts is reduced by epigenetic silencing of the Fas promoter. However, the mechanisms by which microenvironmental stimuli such as TGF-β1 and substrate stiffness affect fibroblast Fas expression are not well understood. Primary normal human lung fibroblasts (IMR-90) were cultured on tissue culture plastic or on polyacrylamide hydrogels with Young's moduli to recapitulate the compliance of normal (400 Pa) or fibrotic (6400 Pa) lung tissue and treated with or without TGF-β1 (10 ng/mL) in the presence or absence of protein kinase inhibitors and/or inflammatory cytokines. Expression of Fas was assessed by quantitative real time RT-PCR, ELISA and Western blotting. Soluble Fas (sFas) was measured in conditioned media by ELISA. Apoptosis was assessed using the Cell Death Detection Kit and by Western blotting for cleaved PARP. Fas expression and susceptibility to apoptosis was diminished in fibroblasts cultured on 6400 Pa substrates compared to 400 Pa substrates. TGF-β1 reduced Fas mRNA and protein in a time- and dose-dependent manner dependent on focal adhesion kinase (FAK). Surprisingly, TGF-β1 did not significantly alter cell-surface Fas expression, but did stimulate secretion of sFas. Finally, enhanced Fas expression and increased susceptibility to apoptosis was induced by combined treatment with TNF-α/IFN-γ and was not inhibited by TGF-β1. Soluble and matrix-mediated pro-fibrotic stimuli promote fibroblast resistance to apoptosis by decreasing Fas transcription while stimulating soluble

S-allyl cysteine in combination with clotrimazole downregulates Fas induced apoptotic events in erythrocytes of mice exposed to lead.

PubMed

Mandal, Samir; Mukherjee, Sudip; Chowdhury, Kaustav Dutta; Sarkar, Avik; Basu, Kankana; Paul, Soumosish; Karmakar, Debasish; Chatterjee, Mahasweta; Biswas, Tuli; Sadhukhan, Gobinda Chandra; Sen, Gargi

2012-01-01

Chronic lead (Pb(2+)) exposure leads to the reduced lifespan of erythrocytes. Oxidative stress and K(+) loss accelerate Fas translocation into lipid raft microdomains inducing Fas mediated death signaling in these erythrocytes. Pathophysiological-based therapeutic strategies to combat against erythrocyte death were evaluated using garlic-derived organosulfur compounds like diallyl disulfide (DADS), S allyl cysteine (SAC) and imidazole based Gardos channel inhibitor clotrimazole (CLT). Morphological alterations in erythrocytes were evaluated using scanning electron microscopy. Events associated with erythrocyte death were evaluated using radio labeled probes, flow cytometry and activity gel assay. Mass spectrometry was used for detection of GSH-4-hydroxy-trans-2-nonenal (HNE) adducts. Fas redistribution into the lipid rafts was studied using immunoblotting technique and confocal microscopy. Combination of SAC and CLT was better than DADS and CLT combination and monotherapy with these agents in prolonging the survival of erythrocytes during chronic Pb(2+) exposure. Combination therapy with SAC and CLT prevented redistribution of Fas into the lipid rafts of the plasma membrane and downregulated Fas-dependent death events in erythrocytes of mice exposed to Pb(2+). Ceramide generation was a critical component of Fas receptor-induced apoptosis, since inhibition of acid sphingomyelinase (aSMase) interfered with Fas-induced apoptosis during Pb(2+) exposure. Combination therapy with SAC and CLT downregulated apoptotic events in erythrocytes by antagonizing oxidative stress and Gardos channel that led to suppression of ceramide-initiated Fas aggregation in lipid rafts. Hence, combination therapy with SAC and CLT may be a potential therapeutic option for enhancing the lifespan of erythrocytes during Pb(2+) toxicity. Copyright © 2011 Elsevier B.V. All rights reserved.

Severe necroinflammatory reaction caused by natural killer cell-mediated Fas/Fas ligand interaction and dendritic cells in human hepatocyte chimeric mouse.

PubMed

Okazaki, Akihito; Hiraga, Nobuhiko; Imamura, Michio; Hayes, C Nelson; Tsuge, Masataka; Takahashi, Shoichi; Aikata, Hiroshi; Abe, Hiromi; Miki, Daiki; Ochi, Hidenori; Tateno, Chise; Yoshizato, Katsutoshi; Ohdan, Hideki; Chayama, Kazuaki

2012-08-01

The necroinflammatory reaction plays a central role in hepatitis B virus (HBV) elimination. Cluster of differentiation (CD)8-positive cytotoxic T lymphocytes (CTLs) are thought to be a main player in the elimination of infected cells, and a recent report suggests that natural killer (NK) cells also play an important role. Here, we demonstrate the elimination of HBV-infected hepatocytes by NK cells and dendritic cells (DCs) using urokinase-type plasminogen activator/severe combined immunodeficiency mice, in which the livers were highly repopulated with human hepatocytes. After establishing HBV infection, we injected human peripheral blood mononuclear cells (PBMCs) into the mice and analyzed liver pathology and infiltrating human immune cells with flow cytometry. Severe hepatocyte degeneration was observed only in HBV-infected mice transplanted with human PBMCs. We provide the first direct evidence that massive liver cell death can be caused by Fas/Fas ligand (FasL) interaction provided by NK cells activated by DCs. Treatment of mice with anti-Fas antibody completely prevented severe hepatocyte degeneration. Furthermore, severe hepatocyte death can be prevented by depletion of DCs, whereas depletion of CD8-positive CTLs did not disturb the development of massive liver cell apoptosis. Our findings provide the first direct evidence that DC-activated NK cells induce massive HBV-infected hepatocyte degeneration through the Fas/FasL system and may indicate new therapeutic implications for acute severe/fulminant hepatitis B. Copyright © 2012 American Association for the Study of Liver Diseases.

Methotrexate Induces Apoptosis in Organ-Cultured Nasal Polyps Via the Fas Pathway.

PubMed

Heo, Kyung Wook; Park, Seong Kook; Lee, Yeo Myeong; Choe, Si Hong; Gu, Pyung Mo; Hong, Tae Ui; Hur, Dae Young

2017-05-01

Methotrexate (MTX) is very effective when used to treat chronic inflammatory diseases, and also induces apoptosis in nasal polyps (NPs). Increasing evidence suggests that Fas-Fas ligand (FasL) interactions activate multiple pathways involved in the regulation of immune and inflammatory cell functions. The aim of the present study was to identify pathways activated by Fas signaling when NPs were treated with MTX. Nasal polyps tissues were cultured using an air-liquid interface organ culture method. Cultures were maintained in the absence or presence of MTX (10 or 100 μM) for 24 hours. The authors used the reverse transcription-polymerase chain reaction method and Western blotting to identify pathways activated by Fas when NPs were treated with MTX. The Fas mRNA expression ratio was unchanged upon MTX treatment, but the FasL mRNA expression ratio was significantly higher in MTX-treated than nontreated polyps. In addition, the expression levels of the Fas and FasL proteins were significantly higher in polyps treated with both 10 and 100 μM MTX compared with nontreated polyps. Methotrexate induces apoptosis in NPs via the Fas pathway. Future studies should explore the topical use of MTX for NP control. Methotrexate may be a useful alternative steroid-sparing agent for the treatment of NPs.

Influence of fenofibrate treatment on triacylglycerides, diacylglycerides and fatty acids in fructose fed rats.

PubMed

Kopf, Thomas; Schaefer, Hans-Ludwig; Troetzmueller, Martin; Koefeler, Harald; Broenstrup, Mark; Konovalova, Tatiana; Schmitz, Gerd

2014-01-01

Fenofibrate (FF) lowers plasma triglycerides via PPARα activation. Here, we analyzed lipidomic changes upon FF treatment of fructose fed rats. Three groups with 6 animals each were defined as control, fructose-fed and fructose-fed/FF treated. Male Wistar Unilever Rats were subjected to 10% fructose-feeding for 20 days. On day 14, fenofibrate treatment (100 mg/kg p.o.) was initiated and maintained for 7 days. Lipid species in serum were analyzed using mass spectrometry (ESI-MS/MS; LC-FT-MS, GC-MS) on days 0, 14 and 20 in all three groups. In addition, lipid levels in liver and intestine were determined. Short-chain TAGs increased in serum and liver upon fructose-feeding, while almost all TAG-species decreased under FF treatment. Long-chain unsaturated DAG-levels (36:1, 36:2, 36:4, 38:3, 38:4, 38:5) increased upon FF treatment in rat liver and decreased in rat serum. FAs, especially short-chain FAs (12:0, 14:0, 16:0) increased during fructose-challenge. VLDL secretion increased upon fructose-feeding and together with FA-levels decreased to control levels during FF treatment. Fructose challenge of de novo fatty acid synthesis through fatty acid synthase (FAS) may enhance the release of FAs ≤ 16:0 chain length, a process reversed by FF-mediated PPARα-activation.

Methotrexate inhibits the viability of human melanoma cell lines and enhances Fas/Fas-ligand expression, apoptosis and response to interferon-alpha: Rationale for its use in combination therapy

PubMed Central

Nihal, Minakshi; Wu, Jianqiang; Wood, Gary S.

2015-01-01

Melanoma, a highly aggressive form of cancer, is notoriously resistant to available therapies. Methotrexate (MTX), an antifolate, competitively inhibits DNA synthesis and is effective for several types of cancer. In cutaneous T-cell lymphoma (CTCL), MTX increases Fas death receptor by decreasing Fas promoter methylation by blocking the synthesis of SAM, the principal methyl donor for DNMTs, resulting in enhanced Fas-mediated apoptosis. The objective of this study was to explore the effects of MTX in human melanoma. MTX variably inhibited the survival of melanoma cells and induced apoptosis as evident by annexin V positivity and senescence associated β-galactosidase activity induction. Furthermore, MTX caused increased transcript and protein levels of extrinsic apoptotic pathway factors Fas and Fas-ligand, albeit at different levels in different cell lines. Our pyrosequencing studies showed that this increased expression of Fas was associated with Fas promoter demethylation. Overall, the ability of MTX to up-regulate Fas/FasL and enhance melanoma apoptosis through extrinsic as well as intrinsic pathways might make it a useful component of novel combination therapies designed to affect multiple melanoma targets simultaneously. In support of this concept, combination therapy with MTX and interferon-alpha (IFNα) induced significantly greater apoptosis in the aggressive A375 cell line than either agent alone. PMID:24862567

Long noncoding RNA Saf and splicing factor 45 increase soluble Fas and resistance to apoptosis

PubMed Central

Riberdy, Janice M.; Persons, Derek A.; Wilber, Andrew

2016-01-01

In multicellular organisms, cell growth and differentiation is controlled in part by programmed cell death or apoptosis. One major apoptotic pathway is triggered by Fas receptor (Fas)-Fas ligand (FasL) interaction. Neoplastic cells are frequently resistant to Fas-mediated apoptosis, evade Fas signals through down regulation of Fas and produce soluble Fas proteins that bind FasL thereby blocking apoptosis. Soluble Fas (sFas) is an alternative splice product of Fas pre-mRNA, commonly created by exclusion of transmembrane spanning sequences encoded within exon 6 (FasΔEx6). Long non-coding RNAs (lncRNAs) interact with other RNAs, DNA, and proteins to regulate gene expression. One lncRNA, Fas-antisense or Saf, was shown to participate in alternative splicing of Fas pre-mRNA through unknown mechanisms. We show that Saf is localized in the nucleus where it interacts with Fas receptor pre-mRNA and human splicing factor 45 (SPF45) to facilitate alternative splicing and exclusion of exon 6. The product is a soluble Fas protein that protects cells against FasL-induced apoptosis. Collectively, these studies reveal a novel mechanism to modulate this critical cell death program by an lncRNA and its protein partner. PMID:26885613

Distinct role of the Fas rs1800682 and FasL rs763110 polymorphisms in determining the risk of breast cancer among Han Chinese females.

PubMed

Wang, Meng; Wang, Zheng; Wang, Xi-Jing; Jin, Tian-Bo; Dai, Zhi-Ming; Kang, Hua-Feng; Guan, Hai-Tao; Ma, Xiao-Bin; Liu, Xing-Han; Dai, Zhi-Jun

2016-01-01

In recent years, studies have demonstrated that polymorphisms in the promoters of Fas and FasL are significantly associated with breast cancer risk. However, the results of these studies were inconsistent. This case-control study was performed to explore the associations between Fas rs1800682 and FasL rs763110 polymorphisms and breast cancer. A hospital-based case-control study of 560 Han Chinese females with breast cancer (583 controls) was conducted. The MassARRAY system was used to search for a possible association between the disease risk and the two single nucleotide polymorphisms, Fas rs1800682 and FasL rs763110. Statistical analyses were performed using SNPStats software to conduct Pearson's chi-square tests in five different genetic models. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated after adjustment to age and body mass index. PHASE v2.1 software was used to reconstruct all common haplotypes. A statistically significant association was found between Fas rs1800682 and increased breast cancer risk (AG vs AA: OR =1.37, 95% CI =1.06-1.78; AA+AG vs GG: OR =1.32, 95% CI =1.04-1.66), and also it was found that the FasL rs763110 polymorphism may decrease the risk. Stratified analyses demonstrated that the rs763110 polymorphism was associated with lower breast cancer risk among postmenopausal females (heterozygote model: OR =0.69, 95% CI =0.49-0.97; dominant model: OR =0.70, 95% CI =0.51-0.96). The T allele of rs763110 was also associated with a decreased risk of lymph node metastasis (allele model: OR =0.75, 95% CI =0.57-0.97) and an increased risk of the breast cancer being human epidermal growth factor receptor 2 positive (allele model: OR =1.37, 95% CI =1.03-1.18). Moreover, haplotype analysis showed that Ars1800682Trs763110 was associated to a statistically significant degree with lower risk of breast cancer (OR =0.70, 95% CI =0.53-0.91). These data suggest that the presence of Fas rs1800683 is an important risk factor for breast

Magnetic resonance imaging (MRI) findings among children with fetal alcohol syndrome (FAS), partial fetal alcohol syndrome (pFAS) and alcohol related neurodevelopmental disorders (ARND).

PubMed

Anna Dyląg, Katarzyna; Sikora-Sporek, Aleksanda; Bańdo, Bożena; Boroń-Zyss, Joanna; Drożdż, Dorota; Dumnicka, Paulina; Przybyszewska, Katarzyna; Sporek, Mateusz; Walocha, Jerzy W; Wojciechowski, Wadim; Urbanik, Andrzej

The aim of the study was to analyze the findings in MRI (magnetic resonance imaging) of the brain amongst children diagnosed with fetal alcohol syndrome (FAS), partial fetal alcohol syndrome (pFAS) or alcohol related neurodevelopmental disorders (ARND). The issue has been studied in several researches previously but the experts agree that there is still few data on the MRI results in the group of younger children. MRI results of 121 patients with either FAS or pFAS or ARND diagnosed with Canadian criteria were analyzed regarding the presence of abnormalities. The group consisted of 71 patients diagnosed with FAS, 33 diagnosed with pFAS and 17 diagnosed with ARND. The mean age of the patients was 8.03 years (standard deviation 4.07). In the total group of FASD patients 61.98% of the patients’ MRI results were abnormal. The most common abnormality in MRI of the patients were demyelination plaques (incidence 23.1%) and corpus callosum narrowing (20.7%) as well as ventricular asymmetry (18.8%).The demyelination plaques and corpus callosum narrowing were more frequent among children ≤4 years old (41.7% vs 18.6%; p=0.016 and 50.0% vs.13.4%; p<0.001, respectively). Age ≤4 years predicted the presence of demyelination plaques and corpus callosum narrowing independently of FAS diagnosis. Among younger children, multiple central nervous system abnormalities were observed more often than in the older age group (54.2% vs. 14.4%; p<0.001). Odds ratio for multiple changes was 0.84 per one-year increase in age (95% CI 0.73-0.97), p=0.016. Furthermore, in the analysis according to the specific diagnosis, among the patients diagnosed with FAS, multiple anomalies were more common than in pFAS and ARND. Both age ≤4 years and FAS diagnosis were independent predictors for multiple anomalies in multiple logistic regression. In structural brain MRI of younger children, multiple anomalies were found more frequently than among older children. Demyelination plaques and corpus

Clinical utility of urinary soluble Fas in screening for bladder cancer.

PubMed

Srivastava, Anupam Kumar; Singh, Pankaj Kumar; Singh, Dhramveer; Dalela, Divakar; Rath, Srikanta Kumar; Bhatt, Madan Lal Brahma

2016-06-01

Early diagnosis of carcinoma of urinary bladder remains a challenge. Urine cytology, as an adjunct to cystoscopy, is less sensitive for low-grade tumors. Soluble Fas (sFas), a cell-surface receptor and member of the tumor necrosis factor superfamily, is frequently expressed in urinary bladder carcinoma. The objective of this study was to investigate the urinary sFas for diagnosis of transitional cell carcinoma (TCC) of urinary bladder. We examined urinary sFas concentration in 74 controls and 117 cases of TCC, both primary and recurrent disease, by using enzyme-linked immunosorbent assay and compared it with urinary cytology. Urinary sFas concentration was found to be significantly higher in the patient as compared to control group (P < 0.05). An optimal cutoff value of 174.0 pg/mL was proposed. The urinary sFas level was found to have an approximate sensitivity and specificity of 88.03% and 89.19% (P < 0.001), whereas urine cytology had sensitivity of 66.67% and specificity of 95.95%. sFas had better sensitivity in higher grade and both primary and recurrent cases of urinary bladder cancer in comparison with cytology. Out of 15 node positive bladder cancer cases, 13 had high urinary sFas levels, whereas 12 were urinary cytology positive for malignancy. Urinary sFas can be used as a non-invasive diagnostic biomarker for TCC of urinary bladder, both for primary and recurrent disease. © 2014 Wiley Publishing Asia Pty Ltd.

Fas–Fas Ligand: Checkpoint of T Cell Functions in Multiple Sclerosis

PubMed Central

Volpe, Elisabetta; Sambucci, Manolo; Battistini, Luca; Borsellino, Giovanna

2016-01-01

Fas and Fas Ligand (FasL) are two molecules involved in the regulation of cell death. Their interaction leads to apoptosis of thymocytes that fail to rearrange correctly their T cell receptor (TCR) genes and of those that recognize self-antigens, a process called negative selection; moreover, Fas–FasL interaction leads to activation-induced cell death, a form of apoptosis induced by repeated TCR stimulation, responsible for the peripheral deletion of activated T cells. Both control mechanisms are particularly relevant in the context of autoimmune diseases, such as multiple sclerosis (MS), where T cells exert an immune response against self-antigens. This concept is well demonstrated by the development of autoimmune diseases in mice and humans with defects in Fas or FasL. In recent years, several new aspects of T cell functions in MS have been elucidated, such as the pathogenic role of T helper (Th) 17 cells and the protective role of T regulatory (Treg) cells. Thus, in this review, we summarize the role of the Fas–FasL pathway, with particular focus on its involvement in MS. We then discuss recent advances concerning the role of Fas–FasL in regulating Th17 and Treg cells’ functions, in the context of MS. PMID:27729910

Oxidative Processing of Latent Fas in the Endoplasmic Reticulum Controls the Strength of Apoptosis

PubMed Central

Anathy, Vikas; Roberson, Elle; Cunniff, Brian; Nolin, James D.; Hoffman, Sidra; Spiess, Page; Guala, Amy S.; Lahue, Karolyn G.; Goldman, Dylan; Flemer, Stevenson; van der Vliet, Albert; Heintz, Nicholas H.; Budd, Ralph C.; Tew, Kenneth D.

2012-01-01

We recently demonstrated that S-glutathionylation of the death receptor Fas (Fas-SSG) amplifies apoptosis (V. Anathy et al., J. Cell Biol. 184:241–252, 2009). In the present study, we demonstrate that distinct pools of Fas exist in cells. Upon ligation of surface Fas, a separate pool of latent Fas in the endoplasmic reticulum (ER) underwent rapid oxidative processing characterized by the loss of free sulfhydryl content (Fas-SH) and resultant increases in S-glutathionylation of Cys294, leading to increases of surface Fas. Stimulation with FasL rapidly induced associations of Fas with ERp57 and glutathione S-transferase π (GSTP), a protein disulfide isomerase and catalyst of S-glutathionylation, respectively, in the ER. Knockdown or inhibition of ERp57 and GSTP1 substantially decreased FasL-induced oxidative processing and S-glutathionylation of Fas, resulting in decreased death-inducing signaling complex formation and caspase activity and enhanced survival. Bleomycin-induced pulmonary fibrosis was accompanied by increased interactions between Fas-ERp57-GSTP1 and S-glutathionylation of Fas. Importantly, fibrosis was largely prevented following short interfering RNA-mediated ablation of ERp57 and GSTP. Collectively, these findings illuminate a regulatory switch, a ligand-initiated oxidative processing of latent Fas, that controls the strength of apoptosis. PMID:22751926

Fatty acids in breast milk associated with asthma-like symptoms and atopy in infancy: a longitudinal study.

PubMed

Soto-Ramírez, Nelís; Karmaus, Wilfried; Zhang, Hongmei; Liu, Jihong; Billings, Deborah; Gangur, Venugopal; Amrol, David; da Costa, Kerry-Ann; Davis, Susan; Goetzl, Laura

2012-11-01

The relationship between fatty acids (FAs) in breast milk and the risk of childhood allergies is controversial. We prospectively investigated the relationship between FAs in colostrum and breast milk and asthma-like symptoms (AS) and atopy in infancy. Pregnant women were recruited in Columbia and Charleston, South Carolina. Colostrum and mature milk samples were collected. The concentrations of n-3 FAs (eicosapentaenoic acid, α-linolenic acid, docosapentaenoic acid, and docosahexaenoic acid) and n-6 FAs (linoleic acid, arachidonic acid, and eicosadienoic acid) were determined by gas chromatography. AS were ascertained at 6 and 12 months of age and atopy (skin prick test) at 12 months. FAs were dichotomized (high vs. median and low). Generalized estimating equations were used to determine the effect of FAs on repeated AS, compensating for intra-individual correlations and adjusting for confounders. Log-linear regression was used to analyze atopy. FAs were analyzed in 24 colostrum and 78 breast milk samples. High levels of total n-6 (lipid based) FAs in breast milk were associated with an increased risk of AS in infants (risk ratio (RR) = 2.91; 95% confidence interval (CI): 1.37, 6.18), even after controlling for total n-3 FAs (RR = 2.07, 95% CI: 1.12, 3.85). High levels of total n-3 FAs controlling for n-6 FAs decreased the risk of atopy at the age of 12 months. High levels of total n-6 polyunsaturated fatty acids (PUFAs) in breast milk are associated with an increased risk for AS, whereas high levels of total n-3 PUFAs decreased the risk of atopy. These data suggest that the effects of n-3 and n-6 PUFAs on allergic disorders should be further explored.

Epstein-Barr Virus Latent Membrane Protein 2A (LMP2A)-Mediated changes in Fas Expression and Fas-Dependent Apoptosis: Role of Lyn/Syk activation

PubMed Central

Incrocci, Ryan; Hussain, Samira; Stone, Amanda; Bieging, Kathryn; Alt, Lauren A.C.; Fay, Michael J.; Swanson-Mungerson, Michelle

2015-01-01

Epstein-Barr virus Latent Membrane Protein 2A (LMP2A) is expressed in EBV-infected B cells in the germinal center, a site of significant apoptosis induced by engagement of Fas on activated B cells. Signals from the B cell receptor (BCR) protect germinal center B cells from Fas-mediated apoptosis, and since LMP2A is a BCR mimic, we hypothesized that LMP2A would also protect B cells from Fas-mediated apoptosis. Surprisingly, latently-infected human and murine B cell lines expressing LMP2A were more sensitive to Fas-mediated apoptosis, as determined by increases in Annexin-V staining, and cleavage of caspase-8, −3 and PARP. Additional studies show that LMP2A-expressing B cell lines demonstrate a Lyn- and Syk-dependent increase in sensitivity to Fas-mediated apoptosis, due to an LMP2A-dependent enhancement in Fas expression. These findings demonstrate the ability for LMP2A to directly increase a pro-apoptotic molecule and have implications for EBV latency as well as the treatment of EBV-associated malignancies. PMID:26255694

Expression of miR-625 and Fas in cervical vertebral cartilage endplate.

PubMed

Zhan, Beilei; Zhan, Yan; Wang, Wei; Zhan, Yunzhong; Liu, Bingsheng

2018-01-01

The aim of the present study was to assess miR-625 and Fas expression in normal and degenerative cervical cartilage endplate (CEP) tissues. Following biof-informatics analysis, the Fas gene was predicted to be one of the targets of miR-625. Quantitative PCR (qPCR) and western blotting were used to detect miR-625 and Fas expression in normal and degenerative CEP. A luciferase reporter assay was used to identify whether miR-625 could directly target the 3' untranslated region (3'-UTR) of Fas. Lentiviral overexpression and/or inhibition vectors of miR-625 (pre-miR-625)/antigomiR-625 were constructed to determine whether overexpression or inhibition of miR-625 could affect Fas and B-cell lymphoma 2 (Bcl-2) expression in cartilaginous endplate cells (CECs) and tissues. qPCR analysis demonstrated that miR-625 expression in degenerative CEP was significantly lower than in normal CEP tissue, while the production of Fas in degenerated CEP was significantly higher. Results from western blotting also showed a significant increase in Fas expression in degenerative CEP. miR-625 can bind directly to the 3'-UTR of the Fas gene. However, this inhibition was attenuated by a target mutation in the miR-625-binding site of the 3'-UTR of Fas mRNA. In addition, following transfection of CECs with pre-miR-625 and antigomiR-625, expression of Fas significantly decreased and increased, respectively, and Bcl-2 expression was upregulated and downregulated, respectively. Upregulation of miR-625 can inhibit Fas expression and further affect Bcl-2 expression in CEP degeneration, suggesting that miR-625-mediated inhibition of the Fas gene is important in cervical degeneration.

CD3+ CD8+ NKG2D+ T Lymphocytes Induce Apoptosis and Necroptosis in HLA-Negative Cells via FasL-Fas Interaction.

PubMed

Ivanova, Olga K; Sharapova, Tatiana N; Romanova, Elena A; Soshnikova, Natalia V; Sashchenko, Lidia P; Yashin, Denis V

2017-10-01

An important problem in cellular immunology is to identify new populations of cytotoxic lymphocytes capable of killing tumor cells that have lost classical components of MHC-machinery and to understand mechanisms of the death of these cells. We have previously found that CD4 + CD25 + lymphocytes appear in the lymphokine-activated killer (LAK) cell culture, which carry Tag7 (PGRP-S) and FasL proteins on their surface and can kill Hsp70- and Fas-expressing HLA-negative cells. In this work, we have continued to study the mechanisms of killing of the HLA-negative tumor cells, focusing this time on the CD8 + lymphocytes. We show that after a tumor antigen contact the IL-2 activated CD8 + lymphocytes acquire ability to lyse tumor cells bearing this antigen. However, activation of the CD8 + lymphocytes in the absence of antigen causes appearance of a cytotoxic population of CD8 + NKG2D + lymphocytes, which are able to lyse HLA-negative cancer cells that have lost the classic mechanism of antigen presentation. These cells recognize the noncanonical MicA antigen on the surface of HLA-negative K562 cells but kill them via the FasL-Fas interaction, as do cytotoxic T lymphocytes. FasL presented on the lymphocyte surface can trigger both apoptosis and necroptosis. Unlike in the case of TNFR1, another cell death receptor, no switching to alternative processes has been observed upon induction of Fas-dependent cell death. It may well be that the apoptotic and necroptotic signals are transduced separately in the latter case, with the ability of FasL + lymphocytes to induce necroptosis allowing them to kill tumor cells that escape apoptosis. J. Cell. Biochem. 118: 3359-3366, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Fas activity mediates airway inflammation during mouse adenovirus type 1 respiratory infection.

PubMed

Adkins, Laura J; Molloy, Caitlyn T; Weinberg, Jason B

2018-06-13

CD8 T cells play a key role in clearance of mouse adenovirus type 1 (MAV-1) from the lung and contribute to virus-induced airway inflammation. We tested the hypothesis that interactions between Fas ligand (FasL) and Fas mediate the antiviral and proinflammatory effects of CD8 T cells. FasL and Fas expression were increased in the lungs of C57BL/6 (B6) mice during MAV-1 respiratory infection. Viral replication and weight loss were similar in B6 and Fas-deficient (lpr) mice. Histological evidence of pulmonary inflammation was similar in B6 and lpr mice, but lung mRNA levels and airway proinflammatory cytokine concentrations were lower in MAV-1-infected lpr mice compared to infected B6 mice. Virus-induced apoptosis in lungs was not affected by Fas deficiency. Our results suggest that the proinflammatory effects of CD8 T cells during MAV-1 infection are mediated in part by Fas activation and are distinct from CD8 T cell antiviral functions. Copyright © 2018 Elsevier Inc. All rights reserved.

Fas-L promotes the stem cell potency of adipose-derived mesenchymal cells.

PubMed

Solodeev, Inna; Meilik, Benjamin; Volovitz, Ilan; Sela, Meirav; Manheim, Sharon; Yarkoni, Shai; Zipori, Dov; Gur, Eyal; Shani, Nir

2018-06-11

Fas-L is a TNF family member known to trigger cell death. It has recently become evident that Fas-L can transduce also non-apoptotic signals. Mesenchymal stem cells (MSCs) are multipotent cells that are derived from various adult tissues. Although MSCs from different tissues display common properties they also display tissue-specific characteristics. Previous works have demonstrated massive apoptosis following Fas-L treatment of bone marrow-derived MSCs both in vitro and following their administration in vivo. We therefore set to examine Fas-L-induced responses in adipose-derived stem cells (ASCs). Human ASCs were isolated from lipoaspirates and their reactivity to Fas-L treatment was examined. ASCs responded to Fas-L by simultaneous apoptosis and proliferation, which yielded a net doubling of cell quantities and a phenotypic shift, including reduced expression of CD105 and increased expression of CD73, in association with increased bone differentiation potential. Treatment of freshly isolated ASCs led to an increase in large colony forming unit fibroblasts, likely produced by early stem cell progenitor cells. Fas-L-induced apoptosis and proliferation signaling were found to be independent as caspase inhibition attenuated Fas-L-induced apoptosis without impacting proliferation, whereas inhibition of PI3K and MEK, but not of JNK, attenuated Fas-L-dependent proliferation, but not apoptosis. Thus, Fas-L signaling in ASCs leads to their expansion and phenotypic shift toward a more potent stem cell state. We speculate that these reactions ensure the survival of ASC progenitor cells encountering Fas-L-enriched environments during tissue damage and inflammation and may also enhance ASC survival following their administration in vivo.

Role of Fas and Treg Cells in Fracture Healing as Characterized in the Fas-Deficient (lpr) Mouse Model of Lupus†

PubMed Central

Al-Sebaei, Maisa O; Daukss, Dana M; Belkina, Anna C; Kakar, Sanjeev; Wigner, Nathan A; Cusher, Daniel; Graves, Dana; Einhorn, Thomas; Morgan, Elise; Gerstenfeld, Louis C

2014-01-01

Previous studies showed that loss of tumor necrosis factor α (TNFα) signaling delayed fracture healing by delaying chondrocyte apoptosis and cartilage resorption. Mechanistic studies showed that TNFα induced Fas expression within chondrocytes; however, the degree to which chondrocyte apoptosis is mediated by TNFα alone or dependent on the induction of Fas is unclear. This question was addressed by assessing fracture healing in Fas-deficient B6.MRL/Faslpr/J mice. Loss of Fas delayed cartilage resorption but also lowered bone fraction in the calluses. The reduced bone fraction was related to elevated rates of coupled bone turnover in the B6.MRL/Faslpr/J calluses, as evidenced by higher osteoclast numbers and increased osteogenesis. Analysis of the apoptotic marker caspase 3 showed fewer positive chondrocytes and osteoclasts in calluses of B6.MRL/Faslpr/J mice. To determine if an active autoimmune state contributed to increased bone turnover, the levels of activated T cells and Treg cells were assessed. B6.MRL/Faslpr/J mice had elevated Treg cells in both spleens and bones of B6.MRL/Faslpr/J but decreased percentage of activated T cells in bone tissues. Fracture led to ∼30% to 60% systemic increase in Treg cells in both wild-type and B6.MRL/Faslpr/J bone tissues during the period of cartilage formation and resorption but either decreased (wild type) or left unchanged (B6.MRL/Faslpr/J) the numbers of activated T cells in bone. These results show that an active autoimmune state is inhibited during the period of cartilage resorption and suggest that iTreg cells play a functional role in this process. These data show that loss of Fas activity specifically in chondrocytes prolonged the life span of chondrocytes and that Fas synergized with TNFα signaling to mediate chondrocyte apoptosis. Conversely, loss of Fas systemically led to increased osteoclast numbers during later periods of fracture healing and increased osteogenesis. These findings suggest that retention

Manipulating the Ordered Nanostructure of Self-Assembled Monoolein and Phytantriol Nanoparticles with Unsaturated Fatty Acids.

PubMed

Tran, Nhiem; Mulet, Xavier; Hawley, Adrian M; Fong, Celesta; Zhai, Jiali; Le, Tu C; Ratcliffe, Julian; Drummond, Calum J

2018-02-27

Mesophase structures of self-assembled lyotropic liquid crystalline nanoparticles are important factors that directly influence their ability to encapsulate and release drugs and their biological activities. However, it is difficult to predict and precisely control the mesophase behavior of these materials, especially in complex systems with several components. In this study, we report the controlled manipulation of mesophase structures of monoolein (MO) and phytantriol (PHYT) nanoparticles by adding unsaturated fatty acids (FAs). By using high throughput formulation and small-angle X-ray scattering characterization methods, the effects of FAs chain length, cis-trans isomerism, double bond location, and level of chain unsaturation on self-assembled systems are determined. Additionally, the influence of temperature on the phase behavior of these nanoparticles is analyzed. We found that in general, the addition of unsaturated FAs to MO and PHYT induces the formation of mesophases with higher Gaussian surface curvatures. As a result, a rich variety of lipid polymorphs are found to correspond with the increasing amounts of FAs. These phases include inverse bicontinuous cubic, inverse hexagonal, and discrete micellar cubic phases and microemulsion. However, there are substantial differences between the phase behavior of nanoparticles with trans FA, cis FAs with one double bond, and cis FAs with multiple double bonds. Therefore, the material library produced in this study will assist the selection and development of nanoparticle-based drug delivery systems with desired mesophase.

miR-212-5p suppresses lipid accumulation by targeting FAS and SCD1.

PubMed

Guo, Yajie; Yu, Junjie; Wang, Chunxia; Li, Kai; Liu, Bin; Du, Ying; Xiao, Fei; Chen, Shanghai; Guo, Feifan

2017-10-01

MicroRNAs, a class of small noncoding RNAs, are implicated in controlling a variety of biological processes. We have shown that leucine deprivation suppresses lipogenesis by inhibiting fatty acid synthase (FAS) expression in the liver previously; the aim of our current study is to investigate which kind of microRNA is involved in the regulation of FAS expression in response to leucine deprivation. Here, we indicated that microRNA-212-5p specifically binds to mouse FAS 3'UTR and inhibits its activity. Leucine deficiency significantly increased the mRNA levels of miR-212-5p in the livers of mice. Further studies proved that miR-212-5p also directly binds to the 3'UTR of stearoyl-CoA desaturase-1 (SCD1) to inhibit its activity. Overexpression of miR-212-5p decreases the protein levels of FAS and SCD1 in vitro and in vivo , and silencing of miR-212-5p has the opposite effects in mouse primary hepatocytes. Moreover, overexpression of miR-212-5p significantly decreases triglyceride (TG) accumulation in primary hepatocytes and in the livers of mice injected with adenovirus-mediated overexpressing of miR-212-5p (Ad-miR-212). Interestingly, inhibition of miR-212-5p reverses the suppressive effects of leucine deficiency on FAS and SCD1 expression, as well as TG accumulation in mouse primary hepatocytes. Finally, we demonstrate that leucine deficiency induces the expression of miR-212-5p in a GCN2/ATF4-dependent manner. Taken together, our results demonstrate a novel function of hepatic miR-212-5p in the regulation of lipid metabolism which represents a potential therapeutic target for the treatment of non-alcohol fatty liver diseases (NAFLD). © 2017 Society for Endocrinology.

Absolute versus relative measures of plasma fatty acids and health outcomes: example of phospholipid omega-3 and omega-6 fatty acids and all-cause mortality in women.

PubMed

Miura, Kyoko; Hughes, Maria Celia B; Ungerer, Jacobus P J; Smith, David D; Green, Adèle C

2018-03-01

In a well-characterised community-based prospective study, we aimed to systematically assess the differences in associations of plasma omega-3 and omega-6 fatty acid (FA) status with all-cause mortality when plasma FA status is expressed in absolute concentrations versus relative levels. In a community sample of 564 women aged 25-75 years in Queensland, Australia, baseline plasma phospholipid FA levels were measured using gas chromatography. Specific FAs analysed were eicosapentaenoic acid, docosapentaenoic acid, docosahexaenoic acid, total long-chain omega-3 FAs, linoleic acid, arachidonic acid, and total omega-6 FAs. Levels of each FA were expressed in absolute amounts (µg/mL) and relative levels (% of total FAs) and divided into thirds. Deaths were monitored for 17 years and hazard ratios and 95% confidence intervals calculated to assess risk of death according to absolute versus relative plasma FA levels. In total 81 (14%) women died during follow-up. Agreement between absolute and relative measures of plasma FAs was higher in omega-3 than omega-6 FAs. The results of multivariate analyses for risk of all-cause mortality were generally similar with risk tending to inverse associations with plasma phospholipid omega-3 FAs and no association with omega-6 FAs. Sensitivity analyses examining effects of age and presence of serious medical conditions on risk of mortality did not alter findings. The directions and magnitude of associations with mortality of absolute versus relative FA levels were comparable. However, plasma FA expressed as absolute concentrations may be preferred for ease of comparison and since relative units can be deduced from absolute units.

Fas-Antisense Long Noncoding RNA and Acute Myeloid Leukemia: Is There any Relation?

PubMed

Sayad, Arezou; Hajifathali, Abbas; Hamidieh, Amir Ali; Esfandi, Farbod; Taheri, Mohammad

2018-01-27

In recent years, lncRNAs have been considered as potential predictive biomarkers for prognosis of different human cancers. One example is the FAS antisense RNA 1 (FAS-AS1) located in the 10q23.31 region which is transcribed from the opposite strand of the FAS gene. FAS has an important role in regulation of apoptotic pathways and there is an inverse correlation between FAS-AS1 expression level and production of the soluble form of Fas, so that it might have potential as a therapeutic target to improve chemotherapy effectiveness. In the present study we therefore evaluated FAS-AS1 expression in blood samples of de novo AML patients and healthy controls using real-time quantitative reverse transcription-PCR (qRT-PCR). Our results indicated that the expression level of FAS-AS1 lncRNA demonstrated no significant difference between AML patients and healthy individuals. We conclude from the obtained data that FAS-AS1 is not an informative and reliable biomarker for AML diagnosis, although our results need to be confirmed in further studies. Creative Commons Attribution License

Engineering of Saccharomyces cerevisiae for the synthesis of short chain fatty acids.

PubMed

Leber, Christopher; Da Silva, Nancy A

2014-02-01

Carbon feedstocks from fossilized sources are being rapidly depleted due to rising demand for industrial and commercial applications. Many petroleum-derived chemicals can be directly or functionally substituted with chemicals derived from renewable feedstocks. Several short chain organic acids may fulfill this role using their functional groups as a target for chemical catalysis. Saccharomyces cerevisiae was engineered to produce short chain carboxylic acids (C6 to C10 ) from glucose using the heterologous Homo sapiens type I fatty acid synthase (hFAS). This synthase was activated by phosphopantetheine transfereases AcpS and Sfp from Escherichia coli and Bacillus subtilis, respectively, both in vitro and in vivo. hFAS was produced in the holo-form and produced carboxylic acids in vitro, confirmed by NADPH and ADIFAB assays. Overexpression of hFAS in a yeast FAS2 knockout strain, deficient in de novo fatty acid synthesis, demonstrated the full functional replacement of the native fungal FAS by hFAS. Two active heterologous short chain thioesterases (TEs) from Cuphea palustris (CpFatB1) and Rattus norvegicus (TEII) were evaluated for short chain fatty acid (SCFA) synthesis in vitro and in vivo. Three hFAS mutants were constructed: a mutant deficient in the native TE domain, a mutant with a linked CpFatB1 TE and a mutant with a linked TEII TE. Using the native yeast fatty acid synthase for growth, the overexpression of the hFAS mutants and the short-chain TEs (linked or plasmid-based) increased in vivo caprylic acid and total SCFA production up to 64-fold (63 mg/L) and 52-fold (68 mg/L), respectively, over the native yeast levels. Combined over-expression of the phosphopantetheine transferase with the hFAS mutant resulted in C8 titers of up to 82 mg/L and total SCFA titers of up to 111 mg/L. © 2013 Wiley Periodicals, Inc.

Expression of Fas ligand by microglia: possible role in glioma immune evasion.

PubMed

Badie, B; Schartner, J; Prabakaran, S; Paul, J; Vorpahl, J

2001-11-01

The immune-privileged status of the central nervous system is thought to limit the application of immunotherapy for treatment of malignant brain tumors. Because the Fas pathway has been proposed to play a role in immune evasion, we examined the effect of tumor environment on the expression of Fas ligand (FasL) in a mouse glioma model. Immunoblotting revealed the expression of membrane-bound FasL to nearly double when murine G26 gliomas were propagated intracranially (IC) as compared to subcutaneously (SC). Further analysis by flow cytometry revealed microglia, which were absent in the SC tumors, to account for half of the FasL expression in the IC tumors. Interestingly, when FasL activity was inhibited in IC tumors, the proportion of tumor-infiltrating leukocytes increased three-fold, reaching the same frequency as the SC tumors. These observations suggest that microglia are a major source of FasL expression in brain tumors and possibly contribute to the local immunosuppressive milieu of malignant gliomas.

Surfactant protein D delays Fas- and TRAIL-mediated extrinsic pathway of apoptosis in T cells.

PubMed

Djiadeu, Pascal; Kotra, Lakshmi P; Sweezey, Neil; Palaniyar, Nades

2017-05-01

Only a few extracellular soluble proteins are known to modulate apoptosis. We considered that surfactant-associated protein D (SP-D), an innate immune collectin present on many mucosal surfaces, could regulate apoptosis. Although SP-D is known to be important for immune cell homeostasis, whether SP-D affects apoptosis is unknown. In this study we aimed to determine the effects of SP-D on Jurkat T cells and human T cells dying by apoptosis. Here we show that SP-D binds to Jurkat T cells and delays the progression of Fas (CD95)-Fas ligand and TRAIL-TRAIL receptor induced, but not TNF-TNF receptor-mediated apoptosis. SP-D exerts its effects by reducing the activation of initiator caspase-8 and executioner caspase-3. SP-D also delays the surface exposure of phosphatidylserine. The effect of SP-D was ablated by the presence of caspase-8 inhibitor, but not by intrinsic pathway inhibitors. The binding ability of SP-D to dying cells decreases during the early stages of apoptosis, suggesting the release of apoptotic cell surface targets during apoptosis. SP-D also delays FasL-induced death of primary human T cells. SP-D delaying the progression of the extrinsic pathway of apoptosis could have important implications in regulating immune cell homeostasis at mucosal surfaces.

A Fashi Lymphoproliferative Phenotype Reveals Non-Apoptotic Fas Signaling in HTLV-1-Associated Neuroinflammation.

PubMed

Menezes, Soraya Maria; Leal, Fabio E; Dierckx, Tim; Khouri, Ricardo; Decanine, Daniele; Silva-Santos, Gilvaneia; Schnitman, Saul V; Kruschewsky, Ramon; López, Giovanni; Alvarez, Carolina; Talledo, Michael; Gotuzzo, Eduardo; Nixon, Douglas F; Vercauteren, Jurgen; Brassat, David; Liblau, Roland; Vandamme, Anne Mieke; Galvão-Castro, Bernardo; Van Weyenbergh, Johan

2017-01-01

Human T-cell lymphotropic virus (HTLV)-1 was the first human retrovirus to be associated to cancer, namely adult T-cell leukemia (ATL), but its pathogenesis remains enigmatic, since only a minority of infected individuals develops either ATL or the neuroinflammatory disorder HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). A functional FAS -670 polymorphism in an interferon (IFN)-regulated STAT1-binding site has been associated to both ATL and HAM/TSP susceptibility. Fas hi T stem cell memory (Tscm) cells have been identified as the hierarchical apex of ATL, but have not been investigated in HAM/TSP. In addition, both FAS and STAT1 have been identified in an IFN-inducible HAM/TSP gene signature, but its pathobiological significance remains unclear. We comprehensively explored Fas expression (protein/mRNA) and function in lymphocyte activation, apoptosis, proliferation, and transcriptome, in PBMC from a total of 47 HAM/TSP patients, 40 asymptomatic HTLV-1-infected individuals (AC), and 58 HTLV-1 -uninfected healthy controls. Fas surface expression followed a two-step increase from HC to AC and from AC to HAM/TSP. In HAM/TSP, Fas levels correlated positively to lymphocyte activation markers, but negatively to age of onset, linking Fas hi cells to earlier, more aggressive disease. Surprisingly, increased lymphocyte Fas expression in HAM/TSP was linked to decreased apoptosis and increased lymphoproliferation upon in vitro culture, but not to proviral load. This Fas hi phenotype is HAM/TSP-specific, since both ex vivo and in vitro Fas expression was increased as compared to multiple sclerosis (MS), another neuroinflammatory disorder. To elucidate the molecular mechanism underlying non-apoptotic Fas signaling in HAM/TSP, we combined transcriptome analysis with functional assays, i.e., blocking vs. triggering Fas receptor in vitro with antagonist and agonist-, anti-Fas mAb, respectively. Treatment with agonist anti-Fas mAb restored apoptosis

Synthesis and release of fatty acids by human trophoblast cells in culture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Coleman, R.A.; Haynes, E.B.

1987-11-01

In order to determine whether placental cells can synthesize and release fatty acids, trophoblast cells from term human placentas were established in monolayer culture. The cells continued to secrete placental lactogen and progesterone and maintained specific activities of critical enzymes of triacylglycerol and phosphatidylcholine biosynthesis for 24 to 72 hr in culture. Fatty acid was rapidly synthesized from (/sup 14/C)acetate and released by the cells. Palmitoleic, palmitic, and oleic acids were the major fatty acids synthesized from (/sup 14/C)acetate and released. Small amounts of lauric, myristic, and stearic acids were also identified. (/sup 14/C)acetate was also incorporated into cellular triacylglycerol,more » phospholipid, and cholesterol, but radiolabeled free fatty acid did not accumulate intracellularly. In a pulse-chase experiment, cellular glycerolipids were labeled with (1-/sup 14/C)oleate; trophoblast cells then released /sup 14/C-labeled fatty acid into the media as the cellular content of labeled phospholipid and triacylglycerol decreased without intracellular accumulation of free fatty acid. Twenty percent of the /sup 14/C-label lost from cellular glycerolipid could not be recovered as a chloroform-extractable product, suggesting that some of the hydrolyzed fatty acid had been oxidized. These data indicate that cultured placenta trophoblast cells can release fatty acids that have either been synthesized de novo or that have been hydrolyzed from cellular glycerolipids. Trophoblast cells in monolayer culture should provide an excellent model for molecular studies of placental fatty acid metabolism and release.« less

Fas signaling induces stemness properties in colorectal cancer by regulation of Bmi1.

PubMed

Chen, Jiaxuan; Wang, Yadong; Zhuo, Linghao; Liu, Zhizhong; Liu, Tao; Li, Wenjing; Cai, Yidong; Zheng, Haoxuan

2017-10-01

Fas signaling promotes colorectal cancer (CRC) metastasis by inducing epithelial-mesenchymal transition (EMT). The acquisition of EMT properties in turn induces stemness but the mechanism by which Fas signaling contributes to it still remains unclear. Hence, the aim of this study was to investigate how Fas signaling regulates CRC stemness. For this purpose, soft agar assay, sphere formation assay, cell survival analysis, immunoblot, qRT-PCR, chromatin immunoprecipitation, and luciferase reporter assay were performed. Expression of FasL, Bmi1, and the miR-200c in CRC specimens was examined through immunohistochemistry, qRT-PCR, and immunoblot. In our study, Fas signaling induced stem cell properties in CRC specimens, relying on ERK1/2 MAPK pathway, with Bmi1 being mainly responsible for FasL-induced stemness. FasL treatment promoted Bmi1 expression by inhibiting miR-200c, which targets Bmi1 3'UTR region. Furthermore, FasL-induced Zeb1 binded with miR-200c promoter and inhibited its expression. Moreover, FasL-induced β-catenin nuclear expression promoted Zeb1 expression by binding with Zeb1 promoter. GSK-3β, which regulates β-catenin, was inhibited by FasL-induced ERK1/2 MAPK signaling. Finally, FasL and Bmi1 expression in clinical samples increased during CRC progression, and a positive correlation between them was observed. Patients with high FasL and Bmi1 expression had a worse prognosis than patients with low expression. In conclusion, our results showed that Fas signaling can promote stemness in CRC through the modulation of Bmi1 expression via the ERK1/2 MAPK/GSK-3β/β-catenin/Zeb1/miR-200c axis, suggesting that Fas signaling-based cancer therapies should be administered cautiously, as the activation of this pathway not only leads to apoptosis but also induces stemness in CRC. © 2017 Wiley Periodicals, Inc.

Chemical evolution. XXI - The amino acids released on hydrolysis of HCN oligomers

NASA Technical Reports Server (NTRS)

Ferris, J. P.; Wos, J. D.; Nooner, D. W.; Oro, J.

1974-01-01

Major amino acids released by hydrolysis of acidic and basic HCN oligomers are identified by chromatography as Gly, Asp, and diaminosuccinic acid. Smaller amounts of Ala, Ile and alpha-aminoisobutyric acid are also detected. The amino acids released did not change appreciably when the hydrolysis medium was changed from neutral to acidic or basic. The presence of both meso and d, l-diaminosuccinic acids was established by paper chromatography and on an amino acid analyzer.

HAT1 induces lung cancer cell apoptosis via up regulating Fas.

PubMed

Han, Na; Shi, Lei; Guo, Qiuyun; Sun, Wei; Yu, Yang; Yang, Li; Zhang, Xiaoxi; Zhang, Mengxian

2017-10-27

The dysfunction of apoptosis is one of the factors contributing to lung cancer (LC) growth. Histone acetyltransferase HAT1 can up regulate cell apoptosis. This study aims to investigate the mechanism by which HAT1 induces LC cell (LCC) apoptosis via up regulating the expression of Fas. In this study, the surgically removed human LC tissues were collected. LCCs were isolated from the LC tissues and analyzed for the expression of HAT1 and Fas by RT-qPCR and Western blotting. We observed that the expression of Fas was negatively correlated with PAR2 in LCCs. Activation of PAR2 suppressed the expression of Fas in normal lung epithelial cells. The expression of HAT1 was lower and positively correlated with Fas expression and negatively correlated with PAR2 expression in LCCs. Activation of PAR2 suppressed Fas expression in lung epithelial cells via inhibiting HAT1. Restoration of HAT1 expression restored Fas expression in LCCs and induced LCC apoptosis. In conclusion, less expression of HAT1 in LCCs was associated with the pathogenesis of LC. Up regulation of HAT1 expression in LCCs can induce LCCs apoptosis, which may be a potential novel therapy for the treatment of LC.

Lipid droplets induced by secreted phospholipase A2 and unsaturated fatty acids protect breast cancer cells from nutrient and lipotoxic stress.

PubMed

Jarc, Eva; Kump, Ana; Malavašič, Petra; Eichmann, Thomas O; Zimmermann, Robert; Petan, Toni

2018-03-01

Cancer cells driven by the Ras oncogene scavenge unsaturated fatty acids (FAs) from their environment to counter nutrient stress. The human group X secreted phospholipase A 2 (hGX sPLA 2 ) releases FAs from membrane phospholipids, stimulates lipid droplet (LD) biogenesis in Ras-driven triple-negative breast cancer (TNBC) cells and enables their survival during starvation. Here we examined the role of LDs, induced by hGX sPLA 2 and unsaturated FAs, in protection of TNBC cells against nutrient stress. We found that hGX sPLA 2 releases a mixture of unsaturated FAs, including ω-3 and ω-6 polyunsaturated FAs (PUFAs), from TNBC cells. Starvation-induced breakdown of LDs induced by low micromolar concentrations of unsaturated FAs, including PUFAs, was associated with protection from cell death. Interestingly, adipose triglyceride lipase (ATGL) contributed to LD breakdown during starvation, but it was not required for the pro-survival effects of hGX sPLA 2 and unsaturated FAs. High micromolar concentrations of PUFAs, but not OA, induced oxidative stress-dependent cell death in TNBC cells. Inhibition of triacylglycerol (TAG) synthesis suppressed LD biogenesis and potentiated PUFA-induced cell damage. On the contrary, stimulation of LD biogenesis by hGX sPLA 2 and suppression of LD breakdown by ATGL depletion reduced PUFA-induced oxidative stress and cell death. Finally, lipidomic analyses revealed that sequestration of PUFAs in LDs by sPLA 2 -induced TAG remodelling and retention of PUFAs in LDs by inhibition of ATGL-mediated TAG lipolysis protect from PUFA lipotoxicity. LDs are thus antioxidant and pro-survival organelles that guard TNBC cells against nutrient and lipotoxic stress and emerge as attractive targets for novel therapeutic interventions. Copyright © 2017 Elsevier B.V. All rights reserved.

Adipose Fatty Acid Binding Protein Promotes Saturated Fatty Acid-induced Macrophage Cell Death through Enhancing Ceramide Production

PubMed Central

Zhang, Yuwen; Rao, Enyu; Zeng, Jun; Hao, Jiaqing; Sun, Yanwen; Liu, Shujun; Sauter, Edward R.; Bernlohr, David A.; Cleary, Margot P.; Suttles, Jill; Li, Bing

2016-01-01

Macrophages play a critical role in obesity-associated chronic inflammation and disorders. However, the molecular mechanisms underlying the response of macrophages to elevated fatty acids (FAs) and their contribution to metabolic inflammation in obesity remain to be fully elucidated. Here, we report a new mechanism by which dietary FAs, in particular saturated FAs, are able to directly trigger macrophage cell death. We demonstrated that excess saturated FAs, but not unsaturated FAs, induced the production of cytotoxic ceramides in macrophage cell lines. Most importantly, expression of adipose fatty acid binding protein (A-FABP) in macrophages facilitated metabolism of excess saturated FAs for ceramide synthesis. Inhibition or deficiency of A-FABP in macrophage cell lines decreased saturated FA-induced ceramide production, thereby resulting in reduced cell death. Furthermore, we validated the role of A-FABP in promoting saturated FA-induced macrophage cell death with primary bone-marrow derived macrophages and high-fat diet-induced obese mice. Altogether, our data reveal that excess dietary saturated FAs may serve as direct triggers in induction of ceramide production and macrophage cell death through elevated expression of A-FABP, thus establishing A-FABP as a new molecular sensor in triggering macrophage-associated sterile inflammation in obesity. PMID:27920274

Fas expression in renal cell carcinoma accurately predicts patient survival after radical nephrectomy.

PubMed

Sejima, Takehiro; Morizane, Shuichi; Hinata, Nobuyuki; Yao, Akihisa; Isoyama, Tadahiro; Saito, Motoaki; Takenaka, Atsushi

2012-01-01

To investigate Fas, Fas ligand (FasL) and Bcl-2 expression, which are considered to be important apoptotic regulatory factors in renal cell carcinomas (RCCs). mRNA quantification and immunohistochemistry allowed for the determination of the expression of these three factors in surgically resected tumors from 82 patients with RCC. The correlation of protein and gene expression with more than 10 years of survival data following nephrectomy (along with clinical and pathologic parameters) was analyzed using uni- and multivariate statistical models. A significantly poorer outcome was observed in patients with tumors expressing high levels of Fas mRNA in the multivariate analysis (p = 0.0002). In addition, patient survival was significantly worse in FasL mRNA-positive tumor cases when compared with FasL mRNA-negative cases (p = 0.0345). Ten cases relapsed more than 5 years after nephrectomy. Among them, the tumors of 8 cases (80%) did not express FasL mRNA. Analysis of Bcl-2 did not show statistical significance of Bcl-2 expression as a prognostic indicator. The data suggest that pronounced Fas expression is a surrogate biomarker of active cancer cell proliferation. Given the FasL tumor counterattack theory, FasL overexpression in RCC may be one of the host immune deficiencies, consequently leading to poor prognosis. Copyright © 2012 S. Karger AG, Basel.

Exosomes secreted by human placenta carry functional Fas ligand and TRAIL molecules and convey apoptosis in activated immune cells, suggesting exosome-mediated immune privilege of the fetus.

PubMed

Stenqvist, Ann-Christin; Nagaeva, Olga; Baranov, Vladimir; Mincheva-Nilsson, Lucia

2013-12-01

Apoptosis is crucially important in mediating immune privilege of the fetus during pregnancy. We investigated the expression and in vitro apoptotic activity of two physiologically relevant death messengers, the TNF family members Fas ligand (FasL) and TRAIL in human early and term placentas. Both molecules were intracellularly expressed, confined to the late endosomal compartment of the syncytiotrophoblast, and tightly associated to the generation and secretion of placental exosomes. Using immunoelectron microscopy, we show that FasL and TRAIL are expressed on the limiting membrane of multivesicular bodies where, by membrane invagination, intraluminal microvesicles carrying membranal bioactive FasL and TRAIL are formed and released in the extracellular space as exosomes. Analyzing exosomes secreted from placental explant cultures, to our knowledge, we demonstrate for the first time that FasL and TRAIL are clustered on the exosomal membrane as oligomerized aggregates ready to form death-inducing signaling complex. Consistently, placental FasL- and TRAIL-carrying exosomes triggered apoptosis in Jurkat T cells and activated PBMC in a dose-dependent manner. Limiting the expression of functional FasL and TRAIL to exosomes comprise a dual benefit: 1) storage of exosomal FasL and TRAIL in multivesicular bodies is protected from proteolytic cleavage and 2) upon secretion, delivery of preformed membranal death molecules by exosomes rapidly triggers apoptosis. Our results suggest that bioactive FasL- and TRAIL-carrying exosomes, able to convey apoptosis, are secreted by the placenta and tie up the immunomodulatory and protective role of human placenta to its exosome-secreting ability.

[Effects of Naomaitong combined with mobilization of bone marrow mesenchymal stem cells on neuron apoptosis and expressions of Fas, FasL and caspase-3 proteins in rats with cerebral ischemia].

PubMed

Li, Jian-sheng; Liu, Jing-xia; Tian, Yu-shou; Ren, Wei-hong; Zhang, Xin-feng; Wang, Ding-chao

2009-09-01

To observe the effects of Naomaitong, a compound traditional Chinese herbal medicine, combined with mobilization of bone marrow mesenchymal stem cells (BMSCs) on neuron apoptosis in rats with cerebral ischemia, and to explore the possible mechanism by detecting the expressions of Fas, FasL and caspase-3 proteins. Two hundred and two SD rats were divided into sham-operated group, untreated group, recombinant granulocyte colony-stimulating factor (rG-CSF) group, Naomaitong group and Naomaitong plus rG-CSF group (combination group). Focal cerebral ischemia was induced by intraluminal middle cerebral artery occlusion using a nylon thread with some modification. Rats in the rG-CSF group and the untreated group were administered with rG-CSF 10 microg/(kg x d) by subcutaneous injection 3 d before and 2 d after the operation respectively, once a day, and rats in the Naomaitong group and the combination group were intragastrically administered Naomaitong before and after the operation until sacrificed. Two, three, seven and fourteen days after operation, count of CD34-positive cells in peripheral blood and CD34 expression in brain tissue were determined. General neural function score (GNFS) was evaluated. Neuron apoptosis, expressions of Fas, FasL and caspase-3 in rat's brain were all measured. Count of CD34-positive cells in peripheral blood and CD34 expression in brain tissue were high in the untreated group, and reached the peak at 3 d and 7 d respectively. CD34 expression in brain tissue was increased in each treated group, especially in the combination group. GNFS was increased at 3 d and 7 d in the untreated group, 7 d and 14 d in the rG-CSF group and the combination group. Expressions of Fas, FasL and caspase-3 were increased 2, 3 and 7 d after operation, while expression of FasL at 2 d in the rG-CSF group, expressions of Fas, FasL and caspase-3 in the combination group were decreased. Expressions of Fas, FasL and caspase-3 at 7 d and 14 d in the combination group

MMP-7, sFas and FasL serum levels for predicting docetaxel resistance and survival in castration-resistant prostate cancer.

PubMed

Szarvas, Tibor; Sevcenco, Sabina; Módos, Orsolya; Keresztes, Dávid; Nyirády, Péter; Csizmarik, Anita; Ristl, Robin; Puhr, Martin; Hoffmann, Michèle J; Niedworok, Christian; Hadaschik, Boris; Maj-Hes, Agnieszka; Shariat, Shahrokh F; Kramer, Gero

2018-05-26

To assess the predictive value of pre-chemotherapy MMP-7, sFas, FasL serum levels as well as their changes during therapy. Serum levels of MMP-7, Fas and FasL were determined by ELISA in 96 CRPC patients; 21 docetaxel-resistant who received one single series and 75 docetaxel-sensitive who received repeated series of docetaxel. In addition to the 96 pretreatment serum samples, 987 sera collected during chemotherapy were also analysed. Higher pretreatment serum MMP-7, sFas and PSA levels were significantly associated with both docetaxel-resistance (p=0.007, p=0.001, p<0.001, respectively) and shorter cancer-specific survival (p<0.001, p=0.041, p<0.001, respectively). High MMP-7 remained an independent predictor of both docetaxel resistance (HR: 2.298, 95% CI: 1.354-3.899, p=0.002) and poor cancer-specific survival (HR=2.11, 95%Cl 1.36-3.30, p=0.001) in multivariable analyses. Higher increase of MMP-7 levels in the 2 nd treatment holiday and higher increase of PSA levels in the 1 st and 2 nd holidays were predictive of survival. Pretreatment serum MMP-7 levels may help to select CRPC patients who are likely to benefit from docetaxel chemotherapy. Furthermore, MMP-7 alone or in combination with PSA could be used for therapy monitoring. Correlative studies embedded in clinical trials are necessary to validate these biomarkers for clinical decision-making. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Lack of FasL-mediated killing leads to in vivo tumor promotion in mouse Lewis lung cancer.

PubMed

Lee, J-K; Sayers, T J; Back, T C; Wigginton, J M; Wiltrout, R H

2003-03-01

Lewis lung carcinoma (3LL) cells were constitutively resistant to Fas-mediated apoptosis, but overexpression of Fas on 3LL cells allowed Fas-mediated apoptosis after crosslinking with agonist anti-Fas antibody (Jo2) in vitro. Surprisingly, Fas-overexpressing 3LL cells showed enhanced in vivo tumor progression, whereas no promotion of in vivo tumor growth was observed for dominant negative (DN) Fas-overexpressing 3LL transfectants in which the cytoplasmic death domain was deleted. In addition, the promotion of in vivo tumor growth by Fas-overexpression was reduced in gld (FasL-mutation) mice compared to normal mice. These data indicate that intact Fas/FasL cell signaling is required for the promotion of in vivo tumor growth by Fas overexpression in 3LL cells. In contrast to the efficient Fas-mediated killing induced in vitro by crosslinking with anti-Fas antibody, Fas-overexpressing 3LL cells were resistant in vitro to Fas-mediated apoptosis by activated T cells or transient FasL transfection. These data suggest that agonist anti-Fas antibody and natural FasL can transmit qualitatively different signals, and crosslinking of Fas with natural FasL on 3LL cells does not deliver the expected death signal. Thus, our results demonstrate that in some cases overexpression of Fas can result in a survival advantage for tumor cells in vivo.

Molecular cloning, functional identification and expressional analyses of FasL in Tilapia, Oreochromis niloticus.

PubMed

Ma, Tai-yang; Wu, Jin-ying; Gao, Xiao-ke; Wang, Jing-yuan; Zhan, Xu-liang; Li, Wen-sheng

2014-10-01

FasL is the most extensively studied apoptosis ligand. In 2000, tilapia FasL was identified using anti-human FasL monoclonal antibody by Evans's research group. Recently, a tilapia FasL-like protein of smaller molecule weight was predicted in Genbank (XM_003445156.2). Based on several clues drawn from previous studies, we cast doubt on the authenticity of the formerly identified tilapia FasL. Conversely, using reverse transcription polymerase chain reaction (RT-PCR), the existence of the predicted FasL-like was verified at the mRNA level (The Genbank accession number of the FasL mRNA sequence we cloned is KM008610). Through multiple alignments, this FasL-like protein was found to be highly similar to the FasL of the Japanese flounder. Moreover, we artificially expressed the functional region of the predicted protein and later confirmed its apoptosis-inducing activity using a methyl thiazolyl tetrazolium (MTT) assay, Annexin-V/Propidium iodide (PI) double staining, and DNA fragment detection. Supported by these evidences, we suggest that the predicted protein is the authentic tilapia FasL. To advance this research further, tilapia FasL mRNA and its protein across different tissues were quantified. High expression levels were identified in the tilapia immune system and sites where active cell turnover conservatively occurs. In this regard, FasL may assume an active role in the immune system and cell homeostasis maintenance in tilapia, similar to that shown in other species. In addition, because the distribution pattern of FasL mRNA did not synchronize with that of the protein, post-transcriptional expression regulation is suggested. Such regulation may be dominated by potential adenylate- and uridylate-rich elements (AREs) featuring AUUUA repeats found in the 3' untranslated region (UTR) of tilapia FasL mRNA. Copyright © 2014 Elsevier Ltd. All rights reserved.

Western and Chinese antirheumatic drug-induced T cell apoptotic DNA damage uses different caspase cascades and is independent of Fas/Fas ligand interaction.

PubMed

Lai, J H; Ho, L J; Lu, K C; Chang, D M; Shaio, M F; Han, S H

2001-06-01

Spontaneous or therapeutic induction of T cell apoptosis plays a critical role in establishing transplantation tolerance and maintaining remission of autoimmune diseases. We investigated the mechanisms of apoptosis induced by Chinese and Western antirheumatic drugs (ARDs) in human T cells. We found that hydroxychloroquine, Tripterygium wilfordii hook F, and tetrandrine (Tet), but not methotrexate, at therapeutic concentrations can cause T cell death. In addition, Tet selectively killed T cells, especially activated T cells. Although ARD-induced cytotoxicity was mediated through apoptotic mechanisms, Fas/Fas ligand interaction was not required. We further demonstrated that the processes of phosphatidylserine externalization and DNA damage along the ARD-induced T cell apoptotic pathway could operate independently, and that selective inhibition of DNA damage by caspase inhibitors did not prevent T cells from undergoing cell death. Moreover, we found that Tet- and Tripterygium wilfordii hook F-induced T cell DNA damage required caspase-3 activity, and hydroxychloroquine-induced T cell DNA damage was mediated through a caspase-3- and caspase-8-independent, but Z-Asp-Glu-Val-Asp-fluomethyl ketone-sensitive, signaling pathway. Finally, the observation that ARD-induced activation of caspase-3 in both Fas-sensitive and Fas-resistant Jurkat T cells indicates that Fas/Fas ligand interaction plays no role in ARD-induced T cell apoptosis. Our observations provide new information about the complex apoptotic mechanisms of ARDs, and have implications for combining Western and Chinese ARDs that have different immunomodulatory mechanisms in the therapy of autoimmune diseases and transplantation rejection.

Fatty acid synthase inhibition in human breast cancer cells leads to malonyl-CoA-induced inhibition of fatty acid oxidation and cytotoxicity.

PubMed

Thupari, J N; Pinn, M L; Kuhajda, F P

2001-07-13

Inhibition of fatty acid synthase (FAS) induces apoptosis in human breast cancer cells in vitro and in vivo without toxicity to proliferating normal cells. We have previously shown that FAS inhibition causes a rapid increase in malonyl-CoA levels identifying malonyl-CoA as a potential trigger of apoptosis. In this study we further investigated the role of malonyl-CoA during FAS inhibition. We have found that: [i] inhibition of FAS with cerulenin causes carnitine palmitoyltransferase-1 (CPT-1) inhibition and fatty acid oxidation inhibition in MCF-7 human breast cancer cells likely mediated by elevation of malonyl-CoA; [ii] cerulenin cytotoxicity is due to the nonphysiological state of increased malonyl-CoA, decreased fatty acid oxidation, and decreased fatty acid synthesis; and [iii] the cytotoxic effect of cerulenin can be mimicked by simultaneous inhibition of CPT-1, with etomoxir, and fatty acid synthesis with TOFA, an acetyl-CoA carboxylase (ACC) inhibitor. This study identifies CPT-1 and ACC as two new potential targets for cancer chemotherapy. Copyright 2001 Academic Press.

Cytokine-mediated FOXO3a phosphorylation suppresses FasL expression in hemopoietic cell lines: investigations of the role of Fas in apoptosis due to cytokine starvation.

PubMed

Behzad, Hayedeh; Jamil, Sarwat; Denny, Trisha A; Duronio, Vincent

2007-05-01

We have investigated phosphatidylinositol 3-kinase (PI3K)-dependent survival signalling pathways using several cytokines in three different hemopoietic cell lines, MC/9, FDC-P1, and TF-1. Cytokines caused PI3K- and PKB-dependent phosphorylation of FOXO3a (previously known as FKHRL1) at three distinct sites. Following cytokine withdrawal or PI3K inhibition, both of which are known to lead to apoptosis, there was a loss of FOXO3a phosphorylation, and a resulting increase in forkhead transcriptional activity, along with increased expression of Fas Ligand (FasL), which could be detected at the cell surface. Concurrently, an increase in cell surface expression of Fas was also detected. Despite the presence of both FasL and Fas, there was no detectable evidence that activation of Fas-mediated apoptotic events was contributing to apoptosis resulting from cytokine starvation or inhibition of PI3K activity. Thus, inhibition of FOXO3a activity is mediated by the PI3K-PKB pathway, but regulation of FasL is not the primary means by which cell survival is regulated in cytokine-dependent hemopoietic cells. We were also able to confirm increased expression of known FOXO3a targets, Bim and p27kip1. Together, these results support the conclusion that mitochondrial-mediated signals play the major role in apoptosis of hemopoietic cells due to loss of cytokine signalling.

Fas/CD95 prevents autoimmunity independently of lipid raft localization and efficient apoptosis induction

PubMed Central

Cruz, Anthony C.; Ramaswamy, Madhu; Ouyang, Claudia; Klebanoff, Christopher A.; Sengupta, Prabuddha; Yamamoto, Tori N.; Meylan, Françoise; Thomas, Stacy K.; Richoz, Nathan; Eil, Robert; Price, Susan; Casellas, Rafael; Rao, V. Koneti; Lippincott-Schwartz, Jennifer; Restifo, Nicholas P.; Siegel, Richard M.

2016-01-01

Mutations affecting the apoptosis-inducing function of the Fas/CD95 TNF-family receptor result in autoimmune and lymphoproliferative disease. However, Fas can also costimulate T-cell activation and promote tumour cell growth and metastasis. Palmitoylation at a membrane proximal cysteine residue enables Fas to localize to lipid raft microdomains and induce apoptosis in cell lines. Here, we show that a palmitoylation-defective Fas C194V mutant is defective in inducing apoptosis in primary mouse T cells, B cells and dendritic cells, while retaining the ability to enhance naive T-cell differentiation. Despite inability to efficiently induce cell death, the Fas C194V receptor prevents the lymphoaccumulation and autoimmunity that develops in Fas-deficient mice. These findings indicate that induction of apoptosis through Fas is dependent on receptor palmitoylation in primary immune cells, and Fas may prevent autoimmunity by mechanisms other than inducing apoptosis. PMID:28008916

Expression of TRAIL and Fas in Primary Hyperparathyroidism.

PubMed

Segiet, Oliwia Anna; Deska, Mariusz; Mielańczyk, Łukasz; Brzozowa-Zasada, Marlena; Buła, Grzegorz; Gawrychowski, Jacek; Wojnicz, Romuald

2017-08-01

Differentiating between parathyroid lesions is still difficult and ambiguous. In cases of primary hyperparathyroidism, appropriate and prompt diagnosis is of great importance for effective treatment and follow-up. A great amount of mechanisms contribute to the pathogenesis of primary hyperparathyroidism, such as disturbance in balance between pro- and anti-apoptotic factors. Therefore, we examined whether immunohistochemical expression of apoptotic factors, TNF-related apoptosis-inducing ligand (TRAIL) and Fas, could have clinical utility as a marker of proliferative lesions of parathyroid gland. Parathyroid specimens of 58 consecutive patients who had undertaken surgery due to primary hyperparathyroidism were incubated with purified mouse monoclonal antihuman antibodies: anti-TRAIL and anti-Fas. Staining was considered positive when at least 5% of the cells showed immunoreactivity. The percentage of cells which were positively stained for TRAIL in parathyroid hyperplasia was 9.65%, in parathyroid adenoma 8.31%, and in normal controls 2.24%. Immunoreactivity for TRAIL was detected in 91.89% of parathyroid hyperplasias, 85.71% of parathyroid adenomas, and none in healthy glands. The percentage of cells with a positive reaction to Fas in parathyroid hyperplasia was 8.92%, in parathyroid adenoma 8.09%, and in normal tissue 1.9%. The expression of Fas was found in 94.59% of parathyroid hyperplasias, 90.48% of parathyroid adenomas, and none in healthy glands. In our study, hyperplasias demonstrated the highest expression of TRAIL and Fas, whereas in adenomas it was increased compared to normal tissue, but lower than in hyperplasias. These factors could be an additive tool in the differential diagnosis of parathyroid lesions.

The expression of Fas Ligand by macrophages and its upregulation by human immunodeficiency virus infection.

PubMed Central

Dockrell, D H; Badley, A D; Villacian, J S; Heppelmann, C J; Algeciras, A; Ziesmer, S; Yagita, H; Lynch, D H; Roche, P C; Leibson, P J; Paya, C V

1998-01-01

Fas/Fas Ligand (FasL) interactions play a significant role in peripheral T lymphocyte homeostasis and in certain pathological states characterized by T cell depletion. In this study, we demonstrate that antigen-presenting cells such as monocyte-derived human macrophages (MDM) but not monocyte-derived dendritic cells express basal levels of FasL. HIV infection of MDM increases FasL protein expression independent of posttranslational mechanisms, thus highlighting the virus-induced transcriptional upregulation of FasL. The in vitro relevance of these observations is confirmed in human lymphoid tissue. FasL protein expression is constitutive and restricted to tissue macrophages and not dendritic cells. Moreover, a significant increase in macrophage-associated FasL is observed in lymphoid tissue from HIV (+) individuals (P < 0.001), which is further supported by increased levels of FasL mRNA using in situ hybridization. The degree of FasL protein expression in vivo correlates with the degree of tissue apoptosis (r = 0.761, P < 0. 001), which is significantly increased in tissue from HIV-infected patients (P < 0.001). These results identify human tissue macrophages as a relevant source for FasL expression in vitro and in vivo and highlight the potential role of FasL expression in the immunopathogenesis of HIV infection. PMID:9616211

Altered erythrocyte membrane fatty acid profile in typical Rett syndrome: effects of omega-3 polyunsaturated fatty acid supplementation.

PubMed

Signorini, Cinzia; De Felice, Claudio; Leoncini, Silvia; Durand, Thierry; Galano, Jean-Marie; Cortelazzo, Alessio; Zollo, Gloria; Guerranti, Roberto; Gonnelli, Stefano; Caffarelli, Carla; Rossi, Marcello; Pecorelli, Alessandra; Valacchi, Giuseppe; Ciccoli, Lucia; Hayek, Joussef

2014-11-01

This study mainly aims at examining the erythrocyte membrane fatty acid (FAs) profile in Rett syndrome (RTT), a genetically determined neurodevelopmental disease. Early reports suggest a beneficial effects of omega-3 polyunsaturated fatty acids (ω-3 PUFAs) on disease severity in RTT. A total of 24 RTT patients were assigned to ω-3 PUFAs-containing fish oil for 12 months in a randomized controlled study (average DHA and EPA doses of 72.9, and 117.1mg/kgb.w./day, respectively). A distinctly altered FAs profile was detectable in RTT, with deficient ω-6 PUFAs, increased saturated FAs and reduced trans 20:4 FAs. FAs changes were found to be related to redox imbalance, subclinical inflammation, and decreased bone density. Supplementation with ω-3 PUFAs led to improved ω-6/ω-3 ratio and serum plasma lipid profile, decreased PUFAs peroxidation end-products, normalization of biochemical markers of inflammation, and reduction of bone hypodensity as compared to the untreated RTT group. Our data indicate that a significant FAs abnormality is detectable in the RTT erythrocyte membranes and is partially rescued by ω-3 PUFAs. Copyright © 2014 Elsevier Ltd. All rights reserved.

7 CFR 1484.57 - Will FAS make advance payments to a Cooperator?

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 10 2014-01-01 2014-01-01 false Will FAS make advance payments to a Cooperator? 1484... FOR AGRICULTURAL COMMODITIES Contributions and Reimbursements § 1484.57 Will FAS make advance payments to a Cooperator? (a) Policy. In general, FAS operates the Cooperator program on a reimbursable basis...

7 CFR 1484.57 - Will FAS make advance payments to a Cooperator?

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 10 2013-01-01 2013-01-01 false Will FAS make advance payments to a Cooperator? 1484... FOR AGRICULTURAL COMMODITIES Contributions and Reimbursements § 1484.57 Will FAS make advance payments to a Cooperator? (a) Policy. In general, FAS operates the Cooperator program on a reimbursable basis...

7 CFR 1484.57 - Will FAS make advance payments to a Cooperator?

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 10 2012-01-01 2012-01-01 false Will FAS make advance payments to a Cooperator? 1484... FOR AGRICULTURAL COMMODITIES Contributions and Reimbursements § 1484.57 Will FAS make advance payments to a Cooperator? (a) Policy. In general, FAS operates the Cooperator program on a reimbursable basis...

7 CFR 1484.30 - How does FAS formalize its working relationship with approved Cooperators?

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 10 2011-01-01 2011-01-01 false How does FAS formalize its working relationship with... FAS formalize its working relationship with approved Cooperators? FAS will notify each applicant in writing of the final disposition of its application. FAS will send a program agreement, allocation...

Uterine Spiral Artery Remodeling Involves Endothelial Apoptosis Induced by Extravillous Trophoblasts Through Fas/FasL Interactions

PubMed Central

Ashton, Sandra V.; Whitley, Guy St. J.; Dash, Philip R.; Wareing, Mark; Crocker, Ian P.; Baker, Philip N.; Cartwright, Judith E.

2014-01-01

Objective Invasion of uterine spiral arteries by extravillous trophoblasts in the first trimester of pregnancy results in loss of endothelial and musculoelastic layers. This remodeling is crucial for an adequate blood supply to the fetus with a failure to remodel implicated in the etiology of the hypertensive disorder preeclampsia. The mechanism by which trophoblasts induce this key process is unknown. This study gives the first insights into the potential mechanisms involved. Methods and Results Spiral arteries were dissected from nonplacental bed biopsies obtained at Caesarean section, and a novel model was used to mimic in vivo events. Arteries were cultured with trophoblasts in the lumen, and apoptotic changes in the endothelial layer were detected after 20 hours, leading to loss of endothelium by 96 hours. In vitro, coculture experiments showed that trophoblasts stimulated apoptosis of primary decidual endothelial cells and an endothelial cell line. This was blocked by caspase inhibition and NOK2, a FasL blocking antibody. NOK2 also abrogated trophoblast-induced endothelial apoptosis in the vessel model. Conclusions Extravillous trophoblast induction of endothelial apoptosis is a possible mechanism by which the endothelium is removed, and vascular remodeling may occur in uterine spiral arteries. Fas/FasL interactions have an important role in trophoblast-induced endothelial apoptosis. PMID:15499040

Inhibition of Prolyl Hydroxylase Attenuates Fas Ligand-Induced Apoptosis and Lung Injury in Mice.

PubMed

Nagamine, Yusuke; Tojo, Kentaro; Yazawa, Takuya; Takaki, Shunsuke; Baba, Yasuko; Goto, Takahisa; Kurahashi, Kiyoyasu

2016-12-01

Alveolar epithelial injury and increased alveolar permeability are hallmarks of acute respiratory distress syndrome. Apoptosis of lung epithelial cells via the Fas/Fas ligand (FasL) pathway plays a critical role in alveolar epithelial injury. Activation of hypoxia-inducible factor (HIF)-1 by inhibition of prolyl hydroxylase domain proteins (PHDs) is a possible therapeutic approach to attenuate apoptosis and organ injury. Here, we investigated whether treatment with dimethyloxalylglycine (DMOG), an inhibitor of PHDs, could attenuate Fas/FasL-dependent apoptosis in lung epithelial cells and lung injury. DMOG increased HIF-1α protein expression in vitro in MLE-12 cells, a murine alveolar epithelial cell line. Treatment of MLE-12 cells with DMOG significantly suppressed cell surface expression of Fas and attenuated FasL-induced caspase-3 activation and apoptotic cell death. Inhibition of the HIF-1 pathway by echinomycin or small interfering RNA transfection abolished these antiapoptotic effects of DMOG. Moreover, intraperitoneal injection of DMOG in mice increased HIF-1α expression and decreased Fas expression in lung tissues. DMOG treatment significantly attenuated caspase-3 activation, apoptotic cell death in lung tissue, and the increase in alveolar permeability in mice instilled intratracheally with FasL. In addition, inflammatory responses and histopathological changes were also significantly attenuated by DMOG treatment. In conclusion, inhibition of PHDs protects lung epithelial cells from Fas/FasL-dependent apoptosis through HIF-1 activation and attenuates lung injury in mice.

Analysis of fatty acid composition of sea cucumber Apostichopus japonicus using multivariate statistics

NASA Astrophysics Data System (ADS)

Xu, Qinzeng; Gao, Fei; Xu, Qiang; Yang, Hongsheng

2014-11-01

Fatty acids (FAs) provide energy and also can be used to trace trophic relationships among organisms. Sea cucumber Apostichopus japonicus goes into a state of aestivation during warm summer months. We examined fatty acid profiles in aestivated and non-aestivated A. japonicus using multivariate analyses (PERMANOVA, MDS, ANOSIM, and SIMPER). The results indicate that the fatty acid profiles of aestivated and non-aestivated sea cucumbers differed significantly. The FAs that were produced by bacteria and brown kelp contributed the most to the differences in the fatty acid composition of aestivated and nonaestivated sea cucumbers. Aestivated sea cucumbers may synthesize FAs from heterotrophic bacteria during early aestivation, and long chain FAs such as eicosapentaenoic (EPA) and docosahexaenoic acid (DHA) that produced from intestinal degradation, are digested during deep aestivation. Specific changes in the fatty acid composition of A. japonicus during aestivation needs more detailed study in the future.

7 CFR 1484.57 - Will FAS make advance payments to a Cooperator?

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 10 2010-01-01 2010-01-01 false Will FAS make advance payments to a Cooperator? 1484... DEVELOP FOREIGN MARKETS FOR AGRICULTURAL COMMODITIES Contributions and Reimbursements § 1484.57 Will FAS make advance payments to a Cooperator? (a) Policy. In general, FAS operates the Cooperator program on a...

7 CFR 1484.57 - Will FAS make advance payments to a Cooperator?

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 10 2011-01-01 2011-01-01 false Will FAS make advance payments to a Cooperator? 1484... DEVELOP FOREIGN MARKETS FOR AGRICULTURAL COMMODITIES Contributions and Reimbursements § 1484.57 Will FAS make advance payments to a Cooperator? (a) Policy. In general, FAS operates the Cooperator program on a...

Activation of the Rb/E2F1 pathway by the nonproliferative p38 MAPK during Fas (APO1/CD95)-mediated neuronal apoptosis.

PubMed

Hou, Sheng T; Xie, Xiaoqi; Baggley, Anne; Park, David S; Chen, Gao; Walker, Teena

2002-12-13

Aberrant activation of the Rb/E2F1 pathway in cycling cells, in response to mitogenic or nonmitogenic stress signals, leads to apoptosis through hyperphosphorylation of Rb. To test whether in postmitotic neurons the Rb/E2F1 pathway can be activated by the nonmitogenic stress signaling, we examined the role of the p38 stress-activated protein kinase (SAPK) in regulating Rb phosphorylation in response to Fas (CD95/APO1)-mediated apoptosis of cultured cerebellar granule neurons (CGNs). Anti-Fas antibody induced a dramatic and early activation of p38. Activated p38 was correlated with the induction of hyperphosphorylation of both endogenous and exogenous Rb. The p38-selective inhibitor, SB203580, attenuated such an increase in pRb phosphorylation and significantly protected CGNs from Fas-induced apoptosis. The cyclin-dependent kinase-mediated Rb phosphorylation played a lesser role in this neuronal death paradigm, since cyclin-dependent kinase inhibitors, such as olomoucine, roscovitine, and flavopiridol, did not significantly prevent anti-Fas antibody-evoked neuronal apoptosis. Hyperphosphorylation of Rb by p38 SAPK resulted in the release of Rb-bound E2F1. Increased E2F1 modulated neuronal apoptosis, since E2F1-/- CGNs were significantly less susceptible to Fas-mediated apoptosis in comparison with the wild-type CGNs. Taken together, these studies demonstrate that neuronal Rb/E2F1 is modulated by the nonproliferative p38 SAPK in Fas-mediated neuronal apoptosis.

Reducing isozyme competition increases target fatty acid accumulation in seed triacylglycerols of transgenic Arabidopsis

USDA-ARS?s Scientific Manuscript database

One goal of green chemistry is the production of industrially useful fatty acids (FAs) in crop plants. We focus on the engineering of industrial FAs, specifically hydroxy fatty acids (HFA) and conjugated polyenoic fatty acids (a-eleostearic acid, ESA), using Arabidopsis (Arabidopsis thaliana) as a m...

Development of a Controlled Release of Salicylic Acid Loaded Stearic Acid-Oleic Acid Nanoparticles in Cream for Topical Delivery

PubMed Central

Woo, J. O.; Misran, M.; Lee, P. F.; Tan, L. P.

2014-01-01

Lipid nanoparticles are colloidal carrier systems that have extensively been investigated for controlled drug delivery, cosmetic and pharmaceutical applications. In this work, a cost effective stearic acid-oleic acid nanoparticles (SONs) with high loading of salicylic acid, was prepared by melt emulsification method combined with ultrasonication technique. The physicochemical properties, thermal analysis and encapsulation efficiency of SONs were studied. TEM micrographs revealed that incorporation of oleic acid induces the formation of elongated spherical particles. This observation is in agreement with particle size analysis which also showed that the mean particle size of SONs varied with the amount of OA in the mixture but with no effect on their zeta potential values. Differential scanning calorimetry analysis showed that the SONs prepared in this method have lower crystallinity as compared to pure stearic acid. Different amount of oleic acid incorporated gave different degree of perturbation to the crystalline matrix of SONs and hence resulted in lower degrees of crystallinity, thereby improving their encapsulation efficiencies. The optimized SON was further incorporated in cream and its in vitro release study showed a gradual release for 24 hours, denoting the incorporation of salicylic acid in solid matrix of SON and prolonging the in vitro release. PMID:24578624

Rare splicing defects of FAS underly severe recessive autoimmune lymphoproliferative syndrome.

PubMed

Agrebi, N; Ben-Mustapha, I; Matoussi, N; Dhouib, N; Ben-Ali, M; Mekki, N; Ben-Ahmed, M; Larguèche, B; Ben Becher, S; Béjaoui, M; Barbouche, M R

2017-10-01

Autoimmune lymphoproliferative syndrome (ALPS) is a prototypic disorder of impaired apoptosis characterized by autoimmune features and lymphoproliferation. Heterozygous germline or somatic FAS mutations associated with preserved protein expression have been described. Very rare cases of homozygous germline FAS mutations causing severe autosomal recessive form of ALPS with a complete defect of Fas expression have been reported. We report two unrelated patients from highly inbred North African population showing a severe ALPS phenotype and an undetectable Fas surface expression. Two novel homozygous mutations have been identified underlying rare splicing defects mechanisms. The first mutation breaks a branch point sequence and the second alters a regulatory exonic splicing site. These splicing defects induce the skipping of exon 6 encoding the transmembrane domain of CD95. Our findings highlight the requirement of tight regulation of FAS exon 6 splicing for balanced alternative splicing and illustrate the importance of such studies in highly consanguineous populations. Copyright © 2017 Elsevier Inc. All rights reserved.

Crystallization and X-ray diffraction studies of a complete bacterial fatty-acid synthase type I

DOE Office of Scientific and Technical Information (OSTI.GOV)

Enderle, Mathias; Max-Planck-Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried; McCarthy, Andrew

Bacterial and fungal type I fatty-acid synthases (FAS I) are evolutionarily connected, as bacterial FAS I is considered to be the ancestor of fungal FAS I. In this work, the production, crystallization and X-ray diffraction data analysis of a bacterial FAS I are reported. While a deep understanding of the fungal and mammalian multi-enzyme type I fatty-acid synthases (FAS I) has been achieved in recent years, the bacterial FAS I family, which is narrowly distributed within the Actinomycetales genera Mycobacterium, Corynebacterium and Nocardia, is still poorly understood. This is of particular relevance for two reasons: (i) although homologous to fungalmore » FAS I, cryo-electron microscopic studies have shown that bacterial FAS I has unique structural and functional properties, and (ii) M. tuberculosis FAS I is a drug target for the therapeutic treatment of tuberculosis (TB) and therefore is of extraordinary importance as a drug target. Crystals of FAS I from C. efficiens, a homologue of M. tuberculosis FAS I, were produced and diffracted X-rays to about 4.5 Å resolution.« less

A Fashi Lymphoproliferative Phenotype Reveals Non-Apoptotic Fas Signaling in HTLV-1-Associated Neuroinflammation

PubMed Central

Menezes, Soraya Maria; Leal, Fabio E.; Dierckx, Tim; Khouri, Ricardo; Decanine, Daniele; Silva-Santos, Gilvaneia; Schnitman, Saul V.; Kruschewsky, Ramon; López, Giovanni; Alvarez, Carolina; Talledo, Michael; Gotuzzo, Eduardo; Nixon, Douglas F.; Vercauteren, Jurgen; Brassat, David; Liblau, Roland; Vandamme, Anne Mieke; Galvão-Castro, Bernardo; Van Weyenbergh, Johan

2017-01-01

Human T-cell lymphotropic virus (HTLV)-1 was the first human retrovirus to be associated to cancer, namely adult T-cell leukemia (ATL), but its pathogenesis remains enigmatic, since only a minority of infected individuals develops either ATL or the neuroinflammatory disorder HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). A functional FAS -670 polymorphism in an interferon (IFN)-regulated STAT1-binding site has been associated to both ATL and HAM/TSP susceptibility. Fashi T stem cell memory (Tscm) cells have been identified as the hierarchical apex of ATL, but have not been investigated in HAM/TSP. In addition, both FAS and STAT1 have been identified in an IFN-inducible HAM/TSP gene signature, but its pathobiological significance remains unclear. We comprehensively explored Fas expression (protein/mRNA) and function in lymphocyte activation, apoptosis, proliferation, and transcriptome, in PBMC from a total of 47 HAM/TSP patients, 40 asymptomatic HTLV-1-infected individuals (AC), and 58 HTLV-1 -uninfected healthy controls. Fas surface expression followed a two-step increase from HC to AC and from AC to HAM/TSP. In HAM/TSP, Fas levels correlated positively to lymphocyte activation markers, but negatively to age of onset, linking Fashi cells to earlier, more aggressive disease. Surprisingly, increased lymphocyte Fas expression in HAM/TSP was linked to decreased apoptosis and increased lymphoproliferation upon in vitro culture, but not to proviral load. This Fashi phenotype is HAM/TSP-specific, since both ex vivo and in vitro Fas expression was increased as compared to multiple sclerosis (MS), another neuroinflammatory disorder. To elucidate the molecular mechanism underlying non-apoptotic Fas signaling in HAM/TSP, we combined transcriptome analysis with functional assays, i.e., blocking vs. triggering Fas receptor in vitro with antagonist and agonist-, anti-Fas mAb, respectively. Treatment with agonist anti-Fas mAb restored apoptosis, indicating

Fas ligand expression by astrocytoma in vivo: maintaining immune privilege in the brain?

PubMed Central

Saas, P; Walker, P R; Hahne, M; Quiquerez, A L; Schnuriger, V; Perrin, G; French, L; Van Meir, E G; de Tribolet, N; Tschopp, J; Dietrich, P Y

1997-01-01

Astrocytomas are among the most common brain tumors that are usually fatal in their malignant form. They appear to progress without significant impedance from the immune system, despite the presence of intratumoral T cell infiltration. To date, this has been thought to be the result of T cell immunosuppression induced by astrocytoma-derived cytokines. Here, we propose that cell contact-mediated events also play a role, since we demonstrate the in vivo expression of Fas ligand (FasL/CD95L) by human astrocytoma and the efficient killing of Fas-bearing cells by astrocytoma lines in vitro and by tumor cells ex vivo. Functional FasL is expressed by human, mouse, and rat astrocytoma and hence may be a general feature of this nonlymphoid tumor. In the brain, astrocytoma cells can potentially deliver a death signal to Fas+ cells which include infiltrating leukocytes and, paradoxically, astrocytoma cells themselves. The expression of FasL by astrocytoma cells may extend the processes that are postulated to occur in normal brain to maintain immune privilege, since we also show FasL expression by neurons. Overall, our findings suggest that FasL-induced apoptosis by astrocytoma cells may play a significant role in both immunosuppression and the regulation of tumor growth within the central nervous system. PMID:9077524

Structural and Biophysical Characterization of the Interactions between the Death Domain of Fas Receptor and Calmodulin*

PubMed Central

Fernandez, Timothy F.; Samal, Alexandra B.; Bedwell, Gregory J.; Chen, Yabing; Saad, Jamil S.

2013-01-01

The extrinsic apoptotic pathway is initiated by cell surface death receptors such as Fas. Engagement of Fas by Fas ligand triggers a conformational change that allows Fas to interact with adaptor protein Fas-associated death domain (FADD) via the death domain, which recruits downstream signaling proteins to form the death-inducing signaling complex (DISC). Previous studies have shown that calmodulin (CaM) is recruited into the DISC in cholangiocarcinoma cells, suggesting a novel role of CaM in Fas-mediated signaling. CaM antagonists induce apoptosis through a Fas-related mechanism in cholangiocarcinoma and other cancer cell lines possibly by inhibiting Fas-CaM interactions. The structural determinants of Fas-CaM interaction and the underlying molecular mechanisms of inhibition, however, are unknown. Here we employed NMR and biophysical techniques to elucidate these mechanisms. Our data show that CaM binds to the death domain of Fas (FasDD) with an apparent dissociation constant (Kd) of ∼2 μm and 2:1 CaM:FasDD stoichiometry. The interactions between FasDD and CaM are endothermic and entropically driven, suggesting that hydrophobic contacts are critical for binding. We also show that both the N- and C-terminal lobes of CaM are important for binding. NMR and surface plasmon resonance data show that three CaM antagonists (N-(6-aminohexyl)-5-chloro-1-naphthalene sulfonamide, tamoxifen, and trifluoperazine) greatly inhibit Fas-CaM interactions by blocking the Fas-binding site on CaM. Our findings provide the first structural evidence for Fas-CaM interactions and mechanism of inhibition and provide new insight into the molecular basis for a novel role of CaM in regulating Fas-mediated apoptosis. PMID:23760276

Natural history of autoimmune lymphoproliferative syndrome associated with FAS gene mutations

PubMed Central

Price, Susan; Shaw, Pamela A.; Seitz, Amy; Joshi, Gyan; Davis, Joie; Niemela, Julie E.; Perkins, Katie; Hornung, Ronald L.; Folio, Les; Rosenberg, Philip S.; Puck, Jennifer M.; Hsu, Amy P.; Lo, Bernice; Pittaluga, Stefania; Jaffe, Elaine S.; Fleisher, Thomas A.; Lenardo, Michael J.

2014-01-01

Autoimmune lymphoproliferative syndrome (ALPS) presents in childhood with nonmalignant lymphadenopathy and splenomegaly associated with a characteristic expansion of mature CD4 and CD8 negative or double negative T-cell receptor αβ+ T lymphocytes. Patients often present with chronic multilineage cytopenias due to autoimmune peripheral destruction and/or splenic sequestration of blood cells and have an increased risk of B-cell lymphoma. Deleterious heterozygous mutations in the FAS gene are the most common cause of this condition, which is termed ALPS-FAS. We report the natural history and pathophysiology of 150 ALPS-FAS patients and 63 healthy mutation-positive relatives evaluated in our institution over the last 2 decades. Our principal findings are that FAS mutations have a clinical penetrance of <60%, elevated serum vitamin B12 is a reliable and accurate biomarker of ALPS-FAS, and the major causes of morbidity and mortality in these patients are the overwhelming postsplenectomy sepsis and development of lymphoma. With longer follow-up, we observed a significantly greater relative risk of lymphoma than previously reported. Avoiding splenectomy while controlling hypersplenism by using corticosteroid-sparing treatments improves the outcome in ALPS-FAS patients. This trial was registered at www.clinicaltrials.gov as #NCT00001350. PMID:24398331

Induction of apoptosis in breast cancer cells in vitro by Fas ligand reverse signaling.

PubMed

Kolben, Thomas; Jeschke, Udo; Reimer, Toralf; Karsten, Nora; Schmoeckel, Elisa; Semmlinger, Anna; Mahner, Sven; Harbeck, Nadia; Kolben, Theresa M

2018-02-01

The Fas-antigen is a cell surface receptor that transduces apoptotic signals into cells. The purpose of this study was to evaluate FasL expression in breast cancer and to elucidate the role of its signaling in different breast cancer cell lines. T47D and MCF7 cells were used and cultured in Dulbecco's modified Eagle's medium. FasL translocation to the membrane was achieved by culturing the cells in the presence of human interferon-γ (IFNγ). Translocation was detected by immunofluorescence. The ability of a Fas:Fc fusion protein to trigger apoptosis in these cells was investigated by cell death detection ELISA. After incubation with IFNγ for 4 h and 18 h, apoptosis was assessed in response to treatment with Fas:Fc. Immunofluorescence revealed that the used cell lines were positive for FasL which was increased and changed to more membrane-bound FasL expression after IFNγ stimulation. After stimulation with 50 IU/ml IFNγ, Fas:Fc significantly increased MCF7 apoptosis (1.39 ± 0.06-fold, p = 0.0004) after 18 h. After stimulation with 100 IU/ml, Fas:Fc significantly increased apoptosis both after 4 h (1.49 ± 0.15-fold, p = 0.018) and 18 h (1.30 ± 0.06-fold, p = 0.013). In T47D cells this effect was seen after 4 h of stimulation with 50 IU/ml and addition of Fas:Fc (1.6 ± 0.08-fold, p = 0.03). Membrane-bound FasL expression could be induced by IFNγ in a breast cancer cell model. More importantly, in the presence of IFNγ the Fas:Fc fusion protein was able to transmit pro-apoptotic signals to T47D and MCF7 cells, significantly inducing apoptosis. The current findings support further in vivo studies regarding FasL activation as a potential target for therapeutic intervention in breast cancer.

Optimization of odd chain fatty acid production by Yarrowia lipolytica.

PubMed

Park, Young-Kyoung; Dulermo, Thierry; Ledesma-Amaro, Rodrigo; Nicaud, Jean-Marc

2018-01-01

Odd chain fatty acids (odd FAs) have a wide range of applications in therapeutic and nutritional industries, as well as in chemical industries including biofuel. Yarrowia lipolytica is an oleaginous yeast considered a preferred microorganism for the production of lipid-derived biofuels and chemicals. However, it naturally produces negligible amounts of odd chain fatty acids. The possibility of producing odd FAs using Y. lipolytica was investigated. Y. lipolytica wild-type strain was shown able to grow on weak acids; acetate, lactate, and propionate. Maximal growth rate on propionate reached 0.24 ± 0.01 h -1 at 2 g/L, and growth inhibition occurred at concentration above 10 g/L. Wild-type strain accumulated lipids ranging from 7.39 to 8.14% (w/w DCW) depending on the carbon source composition, and odd FAs represented only 0.01-0.12 g/L. We here proved that the deletion of the PHD1 gene improved odd FAs production, which reached a ratio of 46.82% to total lipids. When this modification was transferred to an obese strain, engineered for improving lipid accumulation, further increase odd FAs production reaching a total of 0.57 g/L was shown. Finally, a fed-batch co-feeding strategy was optimized for further increase odd FAs production, which generated 0.75 g/L, the best production described so far in Y. lipolytica . A Y. lipolytica strain able to accumulate high level of odd chain fatty acids, mainly heptadecenoic acid, has been successfully developed. In addition, a fed-batch co-feeding strategy was optimized to further improve lipid accumulation and odd chain fatty acid content. These lipids enriched in odd chain fatty acid can (1) improve the properties of the biodiesel generated from Y. lipolytica lipids and (2) be used as renewable source of odd chain fatty acid for industrial applications. This work paves the way for further improvements in odd chain fatty acids and fatty acid-derived compound production.

Lack of correlation between serum soluble Fas/APO-1 levels and autoimmune disease.

PubMed

Goel, N; Ulrich, D T; St Clair, E W; Fleming, J A; Lynch, D H; Seldin, M F

1995-12-01

To determine whether elevated soluble Fas/APO-1 (sFas/APO-1) levels are associated with either autoimmune disease or evidence of flares in autoimmune disease. Thirty-seven serum samples were retrospectively obtained from normal controls and patients with laboratory evidence of autoimmune disease activity. These samples were assayed for sFas/APO-1 levels by an enzyme-linked immunosorbent assay, and hospital medical records were retrospectively reviewed for clinical and laboratory characteristics of the patients. Soluble Fas/APO-1 levels did not correlate with clinical diagnoses or laboratory abnormalities. The mean and range of sFas/APO-1 levels were similar in systemic lupus erythematosus patients (including those with active disease), patients with other autoimmune diseases, and normal controls. These data strongly suggest that measurement of sFas/APO-1 levels is unlikely to hold clinical value or play a role in the pathogenesis of autoimmune disease.

Low concentrations of doxycycline attenuates FasL-induced apoptosis in HeLa cells.

PubMed

Yoon, Jung Mi; Koppula, Sushruta; Huh, Se Jong; Hur, Sun Jin; Kim, Chan Gil

2015-07-24

Doxycycline (DC) has been shown to possess non-antibiotic properties including Fas/Fas Ligand (FasL)-mediated apoptosis against several tumor types in the concentration range of 10-40 µg/mL. However, the effect of DC in apoptotic signaling at much low concentrations was not studied. The present study investigated the attenuation effect of low dose of DC on FasL-induced apoptosis in HeLa cell by the methods of MTT assay, fluorescence microscopy, DNA fragmentation, flow cytometry analysis, and western blotting. In the present findings we showed that low concentration of DC (<2.0 µg/mL) exhibited protective effects against FasL-induced apoptosis in HeLa cells. FasL treatment to HeLa cells resulted in a concentration-dependent induction of cell death, and treatment with low concentrations of DC (0.1-2 µg/mL) significantly (p < 0.001) attenuated the FasL-induced cell death as measured by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Further, the FasL-induced apoptotic features in HeLa cells, such as morphological changes, DNA fragmentation and cell cycle arrest was also inhibited by DC (0.5 µg/mL). Tetracycline and minocycline also showed similar anti-apoptotic effects but were not significant when compared to DC, tested at same concentrations. Further, DC (0.01-16 µg/mL) did not influence the hydrogen peroxide- or cisplatin-induced intrinsic apoptotic pathway in HeLa cells. Protein analysis using Western blotting confirmed that FasL-induced cleavage/activation of caspase-8 and caspase-3, were inhibited by DC treatment at low concentration (0.5 µg/mL). Considering the overall data, we report for the first time that DC exhibited anti-apoptotic effects at low concentrations in HeLa cells by inhibition of caspase activation via FasL-induced extrinsic pathway.

Humic acids enhance the microbially mediated release of sedimentary ferrous iron.

PubMed

Chang, Chun-Han; Wei, Chia-Cheng; Lin, Li-Hung; Tu, Tzu-Hsuan; Liao, Vivian Hsiu-Chuan

2016-03-01

Iron (Fe) is an essential element for many organisms, but high concentrations of iron can be toxic. The complex relation between iron, arsenic (As), bacteria, and organic matter in sediments and groundwater is still an issue of environmental concern. The present study addresses the effects of humic acids and microorganisms on the mobilization of iron in sediments from an arsenic-affected area, and the microbial diversity was analyzed. The results showed that the addition of 50, 100, and 500 mg/L humic acids enhanced ferrous iron (Fe(II)) release in a time-dependent and dose-dependent fashion under anaerobic conditions. A significant increase in the soluble Fe(II) concentrations occurred in the aqueous phases of the samples during the first 2 weeks, and aqueous Fe(II) reached its maximum concentrations after 8 weeks at the following Fe(II) concentrations: 28.95 ± 1.16 mg/L (original non-sterilized sediments), 32.50 ± 0.71 mg/L (50 mg/L humic acid-amended, non-sterilized sediments), 37.50 ± 1.85 mg/L (100 mg/L humic acid-amended, non-sterilized sediments), and 39.00 ± 0.43 mg/L (500 mg/L humic acid-amended, non-sterilized sediments). These results suggest that humic acids can further enhance the microbially mediated release of sedimentary iron under anaerobic conditions. By contrast, very insignificant amounts of iron release were observed from sterilized sediments (the abiotic controls), even with the supplementation of humic acids under anaerobic incubation. In addition, the As(III) release was increased from 50 ± 10 μg/L (original non-sterilized sediments) to 110 ± 45 μg/L (100 mg/L humic acid-amended, non-sterilized sediments) after 8 weeks of anaerobic incubation. Furthermore, a microbial community analysis indicated that the predominant class was changed from Alphaproteobacteria to Deltaproteobacteria, and clearly increased populations of Geobacter sp., Paludibacter sp., and Methylophaga sp. were found after adding humic acids

Effect of palmitic acid on the characteristics and release profiles of rotigotine-loaded microspheres.

PubMed

Wang, Aiping; Liang, Rongcai; Liu, Wanhui; Sha, Chunjie; Li, Youxin; Sun, Kaoxiang

2016-01-01

The initial burst release is a major obstacle to the development of microsphere-formulated drug products. To investigate the influence of palmitic acid on the characteristics and release profiles of rotigotine-loaded poly(d,l-lactide-co-glycolide) microspheres. Rotigotine-loaded microspheres (RMS) were prepared using the oil-in-water emulsion solvent evaporation technique. The in vitro characteristics of the RMS were evaluated with scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and a particle size analyzer. The in vitro drug release and in vivo pharmacokinetics of the RMS were investigated. The SEM results showed that the addition of palmitic acid changed the surface morphology of the microspheres from smooth to dimpled and then to non-smooth as the palmitic acid content increased. DSC revealed the existence of molecularly dispersed forms of palmitic acid in the microspheres. The in vitro and in vivo release profiles indicated that the addition of 5% and 8% palmitic acid significantly decreased the burst release of rotigotine from the microspheres, and the late-stage release was delayed as the palmitic acid content increased across the investigated range (5-15%). The addition of palmitic acid to the microspheres significantly affects the release profile of rotigotine from RMS.

MCT1 promotes the cisplatin-resistance by antagonizing Fas in epithelial ovarian cancer.

PubMed

Yan, Chunxiao; Yang, Fan; Zhou, Chunxia; Chen, Xuejun; Han, Xuechuan; Liu, Xueqin; Ma, Hongyun; Zheng, Wei

2015-01-01

This study was designed to investigate the role of MCT1 in the development of cisplatin-resistant ovarian cancer and its possible relationship with Fas. We found the expression of MCT1 was obviously increased both in cisplatin-resistant ovarian cancer tissue and A2780/CP cells compared with sensitive ovarian cancer tissue and cell lines A2780. And in A2780 cells treated with Cisplatin, the expression of MCT1 increased in a concentration-dependent manner, MCT1 knockdown attenuates cisplatin-induced cell viability. In A2780 and A2780/CP cells transfected with MCT1 siRNA, the activation of several downstream targets of Fas, including FasL and FAP-1 were largely prevented, whereas the expression of Caspase-3 was increased, accompanying with increased abundance of Fas. Coimmunoprecipitation and immunofluorescence showed that there is interaction between endogenous MCT1 with Fas in vivo and in vitro. In vivo, depletion of MCT1 by shRNA reverses cisplatin-resistance and the expression of Fas. This study showed that down regulation of MCT1 promote the sensibility to Cisplatin in ovarian cancer cell line. And this effect appeared to be mediated via antagonizing the effect of Fas.

An update on potato crisps contents of moisture, fat, salt and fatty acids (including trans-fatty acids) with special emphasis on new oils/fats used for frying.

PubMed

Gonçalves Albuquerque, Tânia; Sanches-Silva, Ana; Santos, Lèlita; Costa, Helena S

2012-09-01

Eighteen brands of potato crisps, frequently consumed, were analyzed to establish their nutritional value in relation to salt, fat and fatty acid (FA) composition. The purpose of the present study was to determine moisture, total fat, salt contents and FA profiles (including trans-FAs), and to identify the oil/fat used for frying of the 18 brands of potato crisps. Our results show that salt content ranged from 0.127 to 2.77 g/100 g and total fat content of potato crisps varied between 20.0 and 42.8 g/100 g. With respect to FAs analysis, palmitic acid (C16:0), oleic acid (C18:1) and linoleic acid (C18:2) were the major FAs found in the analyzed potato crisps. It is clear from our work that nowadays most potato crisps are currently produced using oils with high contents in unsaturated FAs, which can be considered as healthier from a nutritional point of view. Nevertheless, some brands of potato crisps still use palm oil or a blend of palm oil and other fats/oils, which are very rich in saturated FAs.

Chronic methamphetamine exposure induces cardiac fas-dependent and mitochondria-dependent apoptosis.

PubMed

Liou, Cher-Ming; Tsai, Shiow-Chwen; Kuo, Chia-Hua; Williams, Timothy; Ting, Hua; Lee, Shin-Da

2014-06-01

Very limited information regarding the influence of chronic methamphetamine exposure on cardiac apoptosis is available. In this study, we evaluate whether chronic methamphetamine exposure will increase cardiac Fas-dependent (type I) and mitochondria-dependent (type II) apoptotic pathways. Thirty-two male Wistar rats at 3-4 months of age were randomly divided into a vehicle-treated group [phosphate-buffered saline (PBS) 0.5 ml SQ per day] and a methamphetamine-treated group (MA 10 mg/kg SQ per day) for 3 months. We report that after 3 months of exposure, abnormal myocardial architecture, more minor cardiac fibrosis and cardiac TUNEL-positive apoptotic cells were observed at greater frequency in the MA group than in the PBS group. Protein levels of TNF-α, Fas ligand, Fas receptor, Fas-associated death domain, activated caspase-8, and activated caspase-3 (Fas-dependent apoptosis) extracted from excised hearts were significantly increased in the MA group, compared to the PBS group. Protein levels of cardiac Bak, t-Bid, Bak to Bcl-xL ratio, activated caspase-9, and activated caspase-3 (mitochondria-dependent apoptosis) were significantly increased in the MA group, compared with the PBS group. The results from this study reveal that chronic methamphetamine exposure will activate cardiac Fas-dependent and mitochondria-dependent apoptotic pathways, which may indicate a possible mechanism for developing cardiac abnormalities in humans with chronic methamphetamine abuse.

7 CFR 1580.203 - Determination of eligibility and certification by the Administrator (FAS).

Code of Federal Regulations, 2012 CFR

2012-01-01

... Administrator (FAS). 1580.203 Section 1580.203 Agriculture Regulations of the Department of Agriculture... § 1580.203 Determination of eligibility and certification by the Administrator (FAS). (a) As soon as... Administrator (FAS) shall certify a group of producers as eligible to apply for adjustment assistance under this...

7 CFR 1580.203 - Determination of eligibility and certification by the Administrator (FAS).

Code of Federal Regulations, 2014 CFR

2014-01-01

... Administrator (FAS). 1580.203 Section 1580.203 Agriculture Regulations of the Department of Agriculture... § 1580.203 Determination of eligibility and certification by the Administrator (FAS). (a) As soon as... Administrator (FAS) shall certify a group of producers as eligible to apply for adjustment assistance under this...

7 CFR 1580.203 - Determination of eligibility and certification by the Administrator (FAS).

Code of Federal Regulations, 2013 CFR

2013-01-01

... Administrator (FAS). 1580.203 Section 1580.203 Agriculture Regulations of the Department of Agriculture... § 1580.203 Determination of eligibility and certification by the Administrator (FAS). (a) As soon as... Administrator (FAS) shall certify a group of producers as eligible to apply for adjustment assistance under this...

Inhibition of noradrenaline release by lysergic acid diethylamide

PubMed Central

Hughes, J.

1973-01-01

Lysergic acid diethylamide (LSD) inhibits the release of labelled noradrenaline from the guinea-pig vas deferens during intramural nerve stimulation and causes a corresponding reduction in the contractions of the smooth muscle. These effects of LSD are most prominent at low stimulus frequencies and they are prevented by treatment with phentolamine. It is concluded that LSD inhibits noradrenaline release by interacting with presynaptic α-adrenoceptors. PMID:4788042

Expression of FAS-L Differs from Primary to Relapsed Low-grade Gliomas and Predicts Progression-free Survival.

PubMed

Werner, Jan-Michael; Kuhl, Saskia; Stavrinou, Pantelis; Röhn, Gabriele; Krischek, Boris; Blau, Tobias; Goldbrunner, Roland; Timmer, Marco

2017-12-01

The tumor necrosis factor FAS is overexpressed in high-grade gliomas (HGG). Only little is known about FAS or FAS ligand (FAS-L) in low-grade gliomas (LGG). We explored FAS/FAS-L expression in LGG, focusing on differences in primary and relapsed LGG and on its prognostic value. A total of 133 glioma samples (73 LGG, 60 HGG) were collected. The LGG samples included 15 matched pairs of primary and relapsed tumors. RT-PCR was performed to measure FAS/FAS-L expression, using subunit A, flavoprotein variant (SDHA) as housekeeper. Clinical data included progression free- (PFS) and overall survival (OS). LGG showed significantly lower FAS but higher FAS-L expression than HGG. The FAS-L expression was higher in primary compared to relapsed LGG and had a positive prognostic value concerning PFS (median 45.20 vs. 31.37 months). FAS-L could act as a prognostic marker and potential target in primary LGG. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

FAS/FASL gene polymorphisms in Turkish patients with chronic myeloproliferative disorders.

PubMed

Ozdemirkiran, Fusun Gediz; Nalbantoglu, Sinem; Gokgoz, Zafer; Payzin, Bahriye Kadriye; Vural, Filiz; Cagirgan, Seckin; Berdeli, Afig

2017-03-01

Chronic myeloproliferative disorders (CMPD) are chronic myeloid hematological disorders, characterized by increased myeloid cell proliferation and fibrosis. Impaired apoptotic mechanisms, increased cell proliferation, uncontrolled hematopoietic cell proliferation and myeloaccumulation may contribute to the pathogenesis of CMPD. The aim of our study was to show the possible role of FAS/FASL gene polymorphisms in CMPD pathogenesis and investigate the association with clinical parameters and susceptibility to disease. We included 101 (34 polycythemia vera (PV), 23 primary myelofibrosis (PMF), 44 essential thrombocythemia (ET)) CMPD patients diagnosed according to the WHO classification criteria and 95 healthy controls in this study. All the patients and the controls were investigated for FAS/FASL gene expression, allele frequencies and phenotype features, and also FAS mRNA levels were analyzed. Chronic myeloproliferative disorders patients showed increased FAS-670AG + GG genotype distribution compared with the control group ( p < 0.05). While the A allele was more frequent in both groups, AG genotype was more frequent in CMPD patients. There was no association between FAS-670A>G gene polymorphism and some clinical parameters such as splenomegaly and thrombosis ( p > 0.05). No statistically significant difference in FASL+843C>T genotype or allele frequency was found between groups ( p > 0.05). Moreover, no statistically significant difference was detected in FASL and JAK2V617F mutations ( p > 0.05). FAS mRNA expression was 1.5-fold reduced in patients compared to healthy subjects. According to our findings, FAS/FASL gene expression may contribute to the molecular and immunological pathogenesis of CMPD. More investigations are needed to support these data.

Maternal folic acid supplementation to dams on marginal protein level alters brain fatty acid levels of their adult offspring.

PubMed

Rao, Shobha; Joshi, Sadhana; Kale, Anvita; Hegde, Mahabaleshwar; Mahadik, Sahebarao

2006-05-01

Studies on fetal programming of adult diseases have highlighted the importance of maternal nutrition during pregnancy. Folic acid and long-chain essential polyunsaturated fatty acids (LC-PUFAs) have independent effects on fetal growth. However, folic acid effects may also involve alteration of LC-PUFA metabolism. Because marginal deficiency of LC-PUFAs during critical periods of brain growth and development is associated with risks for adult diseases, it is highly relevant to investigate how maternal supplementation of such nutrients can alter brain fatty acid levels. We examined the impact of folic acid supplementation, conventionally used in maternal intervention, on brain essential fatty acid levels and plasma corticosterone concentrations in adult offspring at 11 months of age. Pregnant female rats from 4 groups (6 in each) were fed with casein diets either with 18 g protein/100 g diet (control diet) or treatment diets that were marginal in protein (MP), such as 12 g protein/100 g diet supplemented with 8 mg folic acid (FAS/MP), 12 g protein/100 g diet without folic acid (FAD/MP), or 12 g protein/100 g diet (MP) with 2 mg folic acid. Pups were weaned to a standard laboratory diet with 18 g protein/100 g diet. All male adult offspring in the FAS/MP group showed lower docosahexaenoic acid (P<.05) as compared with control adult offspring (6.04+/-2.28 vs 10.33+/-0.86 g/100 g fatty acids) and higher n-6/n-3 ratio (P<.05). Docosahexaenoic acid levels in FAS/MP adult offspring were also lower (P<.05) when compared with the MP group. Plasma corticosterone concentrations were higher (P<.05) in male adult offspring from the FAS/MP group compared with control as well as the MP adult offspring. Results suggest that maternal folic acid supplementation at MP intake decreased brain docosahexaenoic acid levels probably involving corticosterone increase.

Different Fatty Acids Compete with Arachidonic Acid for Binding to the Allosteric or Catalytic Subunits of Cyclooxygenases to Regulate Prostanoid Synthesis*

PubMed Central

Dong, Liang; Zou, Hechang; Yuan, Chong; Hong, Yu H.; Kuklev, Dmitry V.; Smith, William L.

2016-01-01

Prostaglandin endoperoxide H synthases (PGHSs), also called cyclooxygenases (COXs), convert arachidonic acid (AA) to PGH2. PGHS-1 and PGHS-2 are conformational heterodimers, each composed of an (Eallo) and a catalytic (Ecat) monomer. Previous studies suggested that the binding to Eallo of saturated or monounsaturated fatty acids (FAs) that are not COX substrates differentially regulate PGHS-1 versus PGHS-2. Here, we substantiate and expand this concept to include polyunsaturated FAs known to modulate COX activities. Non-substrate FAs like palmitic acid bind Eallo of PGHSs stimulating human (hu) PGHS-2 but inhibiting huPGHS-1. We find the maximal effects of non-substrate FAs on both huPGHSs occurring at the same physiologically relevant FA/AA ratio of ∼20. This inverse allosteric regulation likely underlies the ability of PGHS-2 to operate at low AA concentrations, when PGHS-1 is effectively latent. Unlike FAs tested previously, we observe that C-22 FAs, including ω-3 fish oil FAs, have higher affinities for Ecat than Eallo subunits of PGHSs. Curiously, C-20 ω-3 eicosapentaenoate preferentially binds Ecat of huPGHS-1 but Eallo of huPGHS-2. PGE2 production decreases 50% when fish oil consumption produces tissue EPA/AA ratios of ≥0.2. However, 50% inhibition of huPGHS-1 itself is only seen with ω-3 FA/AA ratios of ≥5.0. This suggests that fish oil-enriched diets disfavor AA oxygenation by altering the composition of the FA pool in which PGHS-1 functions. The distinctive binding specificities of PGHS subunits permit different combinations of non-esterified FAs, which can be manipulated dietarily, to regulate AA binding to Eallo and/or Ecat thereby controlling COX activities. PMID:26703471

Mutation in Fas Ligand Impairs Maturation of Thymocytes Bearing Moderate Affinity T Cell Receptors

PubMed Central

Boursalian, Tamar E.; Fink, Pamela J.

2003-01-01

Fas ligand, best known as a death-inducer, is also a costimulatory molecule required for maximal proliferation of mature antigen-specific CD4+ and CD8+ T cells. We now extend the role of Fas ligand by showing that it can also influence thymocyte development. T cell maturation in some, but not all, strains of TCR transgenic mice is severely impaired in thymocytes expressing mutant Fas ligand incapable of interacting with Fas. Mutant Fas ligand inhibits neither negative selection nor death by neglect. Instead, it appears to modulate positive selection of thymocytes expressing both class I– and class II–restricted T cell receptors of moderate affinity for their positively selecting ligands. Fas ligand is therefore an inducer of death, a costimulator of peripheral T cell activation, and an accessory molecule in positive selection. PMID:12860933

Adsorption and release of ofloxacin from acid- and heat-treated halloysite.

PubMed

Wang, Qin; Zhang, Junping; Zheng, Yue; Wang, Aiqin

2014-01-01

Halloysite nanotube is an ideal vehicle of the controlled release of drugs. In this study, we systematically investigated the effects of acid- and heat-treatments on the physicochemical properties, structure and morphology of halloysite by XRD, FTIR, SEM and TEM. Afterwards, the adsorption and in vitro release properties of halloysite for cationic ofloxacin (OFL) were evaluated. The results indicate that HCl treatment has no influence on the crystal structure of halloysite, whereas it becomes amorphous after calcined at temperature higher than 500 °C. Both acid- and heat-treatments have no evident influence on the tubular structure of halloysite. OFL was adsorbed onto halloysite via electrostatic interaction between protonated OFL and negative halloysite surface, cation exchange as well as electrostatic interaction between the OFL-Al(3+) complexes and the negative halloysite surface. Acid-treatment facilitates the release of the adsorbed OFL compared with the natural halloysite in spite of a slight decrease of adsorption capacity. However, heat-treatment results in a sharp decrease of adsorption capacity for OFL owning to the OFL-promoted dissolution of aluminum and the disappearance of the porous structure. Although heat-treatment also facilitates release of the adsorbed OFL, the amount of OFL released is in fact less than the natural halloysite owing to the very low adsorption capacity. Thus, acid-activation is an effective protocol to improve the adsorption and release of halloysite for cationic drug molecules. Copyright © 2013 Elsevier B.V. All rights reserved.

7 CFR 1484.54 - What expenditures may FAS reimburse under the Cooperator program?

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 10 2014-01-01 2014-01-01 false What expenditures may FAS reimburse under the... may FAS reimburse under the Cooperator program? (a) A Cooperator may seek reimbursement for an... source. (b) Subject to paragraph (a) of this section, FAS will reimburse, in whole or in part, the cost...

7 CFR 1484.54 - What expenditures may FAS reimburse under the Cooperator program?

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 10 2012-01-01 2012-01-01 false What expenditures may FAS reimburse under the... may FAS reimburse under the Cooperator program? (a) A Cooperator may seek reimbursement for an... source. (b) Subject to paragraph (a) of this section, FAS will reimburse, in whole or in part, the cost...

7 CFR 1484.54 - What expenditures may FAS reimburse under the Cooperator program?

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 10 2013-01-01 2013-01-01 false What expenditures may FAS reimburse under the... may FAS reimburse under the Cooperator program? (a) A Cooperator may seek reimbursement for an... source. (b) Subject to paragraph (a) of this section, FAS will reimburse, in whole or in part, the cost...

Expression of Fas ligand by human gastric adenocarcinomas: a potential mechanism of immune escape in stomach cancer.

PubMed

Bennett, M W; O'connell, J; O'sullivan, G C; Roche, D; Brady, C; Kelly, J; Collins, J K; Shanahan, F

1999-02-01

Despite being immunogenic, gastric cancers overcome antitumour immune responses by mechanisms that have yet to be fully elucidated. Fas ligand (FasL) is a molecule that induces Fas receptor mediated apoptosis of activated immunocytes, thereby mediating normal immune downregulatory roles including immune response termination, tolerance acquisition, and immune privilege. Colon cancer cell lines have previously been shown to express FasL and kill lymphoid cells by Fas mediated apoptosis in vitro. Many diverse tumours have since been found to express FasL suggesting that a "Fas counterattack" against antitumour immune effector cells may contribute to tumour immune escape. To ascertain if human gastric tumours express FasL in vivo, as a potential mediator of immune escape in stomach cancer. Thirty paraffin wax embedded human gastric adenocarcinomas. FasL protein was detected in gastric tumours using immunohistochemistry; FasL mRNA was detected in the tumours using in situ hybridisation. Cell death was detected in situ in tumour infiltrating lymphocytes using terminal deoxynucleotidyl transferase mediated dUTP nick end labelling (TUNEL). Prevalent expression of FasL was detected in all 30 resected gastric adenocarcinomas examined. In the tumours, FasL protein and mRNA were co-localised to neoplastic gastric epithelial cells, confirming expression by the tumour cells. FasL expression was independent of tumour stage, suggesting that it may be expressed throughout gastric cancer progression. TUNEL staining disclosed a high level of cell death among lymphocytes infiltrating FasL positive areas of tumour. Human gastric adenocarcinomas express the immune downregulatory molecule, FasL. The results suggest that FasL is a prevalent mediator of immune privilege in stomach cancer.

Amino acid neurotransmitter release and learning: a study of visual imprinting.

PubMed

Meredith, R M; McCabe, B J; Kendrick, K M; Horn, G

2004-01-01

The intermediate and medial part of the hyperstriatum ventrale (IMHV) is an area of the domestic chick forebrain that stores information acquired through the learning process of imprinting. The effects of visual imprinting on the release of the amino acids aspartate, arginine, citrulline, gamma-aminobutyric acid (GABA), glutamate, glycine and taurine from the left and right IMHVs in vitro were measured at 3.5, 10 and 24 h after training. Chicks were exposed to an imprinting stimulus for 1 h, their preferences measured 10 min afterward and a preference score calculated as a measure of the strength of learning. Potassium stimulation was used to evoke amino acid release from the IMHVs of trained and untrained chicks in the presence and absence of extracellular Ca2+. Ca2+-dependent, K+-evoked release of glutamate was significantly (34.4%) higher in trained than in untrained chicks. This effect was not influenced by time after training or by side (left or right IMHV). Training influenced the evoked release of GABA and taurine from the left IMHV at both 3.5 and 10 h. The training effects at the two times were statistically homogeneous so data (< or = 10 h group) were combined for each amino acid respectively. For this < or = 10 h group, evoked release increased significantly with preference score. In contrast, for the 24 h group, evoked release of GABA and taurine was not significantly correlated with preference score. There were no significant correlations between preference score and GABA or taurine release in the right IMHV at any time, nor in the absence of extracellular calcium. No significant effects of training condition, time or side were observed for any other amino acid in the study. The present findings suggest that soon after chicks have been exposed to an imprinting stimulus glutamatergic excitatory transmission in IMHV is enhanced, and remains enhanced for at least 24 h. In contrast, the learning-related elevations in taurine and GABA release are not

MCT1 promotes the cisplatin-resistance by antagonizing Fas in epithelial ovarian cancer

PubMed Central

Yan, Chunxiao; Yang, Fan; Zhou, Chunxia; Chen, Xuejun; Han, Xuechuan; Liu, Xueqin; Ma, Hongyun; Zheng, Wei

2015-01-01

This study was designed to investigate the role of MCT1 in the development of cisplatin-resistant ovarian cancer and its possible relationship with Fas. We found the expression of MCT1 was obviously increased both in cisplatin-resistant ovarian cancer tissue and A2780/CP cells compared with sensitive ovarian cancer tissue and cell lines A2780. And in A2780 cells treated with Cisplatin, the expression of MCT1 increased in a concentration-dependent manner, MCT1 knockdown attenuates cisplatin-induced cell viability. In A2780 and A2780/CP cells transfected with MCT1 siRNA, the activation of several downstream targets of Fas, including FasL and FAP-1 were largely prevented, whereas the expression of Caspase-3 was increased, accompanying with increased abundance of Fas. Coimmunoprecipitation and immunofluorescence showed that there is interaction between endogenous MCT1 with Fas in vivo and in vitro. In vivo, depletion of MCT1 by shRNA reverses cisplatin-resistance and the expression of Fas. This study showed that down regulation of MCT1 promote the sensibility to Cisplatin in ovarian cancer cell line. And this effect appeared to be mediated via antagonizing the effect of Fas. PMID:26045776

Promoter hypermethylation and downregulation of the FAS gene may be involved in colorectal carcinogenesis.

PubMed

Manoochehri, Mehdi; Borhani, Nasim; Karbasi, Ashraf; Koochaki, Ameneh; Kazemi, Bahram

2016-07-01

Aberrant DNA methylation has been investigated in carcinogenesis and as biomarker for the early detection of colorectal cancer (CRC). The present study aimed to define the methylation status in the regulatory elements of two proapoptotic genes, Fas cell surface death receptor (FAS) and BCL2-associated X protein (BAX). DNA methylation analysis was performed in tumor and adjacent normal tissue using Hpa II/ Msp I restriction digestion and methylation-specific polymerase chain reaction (PCR). The results observed downregulation of the FAS and BAX genes in the CRC tissues compared with the adjacent normal samples. Furthermore, demethylation using 5-aza-2'-deoxycytidine treatment followed by reverse-transcription quantitative PCR were performed on the HT-29 cell line to measure BAX and FAS mRNA expression following demethylation. The 5-aza-2'-deoxycytidine treatment resulted in significant FAS gene upregulation in the HT-29 cell line, but no significant difference in BAX expression. Furthermore, analysis of CpG islands in the FAS gene promoter revealed that the FAS promoter was significantly hypermethylated in 53.3% of tumor tissues compared with adjacent normal samples. Taken together, the results indicate that decreased expression of the FAS gene due to hypermethylation of its promoter may lead to apoptotic resistance, and acts as an important step during colorectal carcinogenesis.

Novel insights into FAS defects underlying autoimmune lymphoproliferative syndrome revealed by studies in consanguineous patients.

PubMed

Ben-Mustapha, Imen; Agrebi, Nourhen; Barbouche, Mohamed-Ridha

2018-03-01

Autoimmune lymphoproliferative syndrome (ALPS) is a primary immunodeficiency disease due to impaired Fas-Fas ligand apoptotic pathway. It is characterized by chronic nonmalignant, noninfectious lymphadenopathy and/or splenomegaly associated with autoimmune manifestations primarily directed against blood cells. Herein, we review the heterogeneous ALPS molecular bases and discuss recent findings revealed by the study of consanguineous patients. Indeed, this peculiar genetic background favored the identification of a novel form of AR ALPS-FAS associated with normal or residual protein expression, expanding the spectrum of ALPS types. In addition, rare mutational mechanisms underlying the splicing defects of FAS exon 6 have been identified in AR ALPS-FAS with lack of protein expression. These findings will help decipher critical regions required for the tight regulation of FAS exon 6 splicing. We also discuss the genotype-phenotype correlation and disease severity in AR ALPS-FAS. Altogether, the study of ALPS molecular bases in endogamous populations helps to better classify the disease subgroups and to unravel the Fas pathway functioning. ©2017 Society for Leukocyte Biology.

Capture and release of mixed acid gasses with binding organic liquids

DOEpatents

Heldebrant, David J.; Yonker, Clement R.

2010-09-21

Reversible acid-gas binding organic liquid systems that permit separation and capture of one or more of several acid gases from a mixed gas stream, transport of the liquid, release of the acid gases from the ionic liquid and reuse of the liquid to bind more acid gas with significant energy savings compared to current aqueous systems. These systems utilize acid gas capture compounds made up of strong bases and weak acids that form salts when reacted with a selected acid gas, and which release these gases when a preselected triggering event occurs. The various new materials that make up this system can also be included in various other applications such as chemical sensors, chemical reactants, scrubbers, and separators that allow for the specific and separate removal of desired materials from a gas stream such as flue gas.

Partial tolerance of subcutaneously transplanted xenogeneic tumour cell graft by Fas-mediated immunosuppression

PubMed Central

SAWADA, TAKAHIRO; KOJI, TAKEHIKO; HISHIKAWA, YOSHITAKA; KISHIMOTO, KOJI; NAGAYASU, TAKESHI; TAKAHASHI, TAKAO; OKA, TADAYUKI; AYABE, HIROYOSHI

2001-01-01

Certain anti-Fas antibodies, such as RMF2, induce apoptosis of Fas-expressing cells. We applied the Fas/anti-Fas system to induce killing of Fas-expressing immunocytes with resultant immunosuppression. W7TM-1 tumour cells, a rat T-cell line, were inoculated subcutaneously in BALB/c mice and tumour growth was monitored in untreated mice and in mice treated with RMF2. Prior to treatment with RMF2, we examined the expression of Fas in isolated splenocytes and in tumour-infiltrating lymphocytes by flow cytometry and immunohistochemistry, respectively. There was a remarkable increase in Fas-positive lymphocytes, including natural killer (NK) cells, among splenocytes at day 5 after tumour cell inoculation. The number of Fas-positive infiltrating lymphocytes also increased markedly, from day 5 to day 10. We then examined whether RMF2 could induce apoptosis of Fas-positive activated lymphocytes isolated from the spleen at day 5 in vitro. Terminal deoxy (d) -UTP nick end labelling (TUNEL) and Annexin V staining methods showed apoptosis of isolated cells when incubated with RMF2, and typical apoptotic features were confirmed by 4′,6-diamidino-2-phenylindole dihydrochloride (DAPI) staining. Furthermore, suppression of cellular and humoral immunity was noted in RMF2-treated mice by mixed lymphocyte reaction and assay of serum levels of immunoglobulin G, respectively. Finally, treatment of animals with RMF2 daily from day 5 to day 9 could maintain the tumour size, while the tumour mass began to diminish in untreated mice immediately after reaching a maximum size. We confirmed the enhancing effects of long-term treatment with RMF2, through the induction of immunosuppression, on the growth of unvascularized xenogeneic tumour cell grafts. PMID:11380695

Small Interfering RNA-Mediated Suppression of Fas Modulate Apoptosis and Proliferation in Rat Intervertebral Disc Cells.

PubMed

Park, Jong-Beom; Park, Chanjoo

2017-10-01

In vitro cell culture model. To investigate the effect of small interfering RNA (siRNA) on Fas expression, apoptosis, and proliferation in serum-deprived rat disc cells. Synthetic siRNA can trigger an RNA interference (RNAi) response in mammalian cells and precipitate the inhibition of specific gene expression. However, the potential utility of siRNA technology in downregulation of specific genes associated with disc cell apoptosis remains unclear. Rat disc cells were isolated and cultured in the presence of either 10% fetal bovine serum (FBS) (normal control) or 0% FBS (serum deprivation to induce apoptosis) for 48 hours. Fas expression, apoptosis, and proliferation were determined. Additionally, siRNA oligonucleotides against Fas (Fas siRNA) were transfected into rat disc cells to suppress Fas expression. Changes in Fas expression were assessed by reverse transcription-polymerase chain reaction and semiquantitatively analyzed using densitometry. The effect of Fas siRNA on apoptosis and proliferation of rat disc cells were also determined. Negative siRNA and transfection agent alone (Mock) were used as controls. Serum deprivation increased apoptosis by 40.3% ( p <0.001), decreased proliferation by 45.3% ( p <0.001), and upregulated Fas expression. Additionally, Fas siRNA suppressed Fas expression in serum-deprived cultures, with 68.5% reduction at the mRNA level compared to the control cultures ( p <0.001). Finally, Fas siRNA-mediated suppression of Fas expression significantly inhibited apoptosis by 9.3% and increased proliferation by 21% in serum-deprived cultures ( p <0.05 for both). The observed dual positive effect of Fas siRNA might be a powerful therapeutic approach for disc degeneration by suppression of harmful gene expression.

Biological and therapeutic effects of ortho-silicic acid and some ortho-silicic acid-releasing compounds: New perspectives for therapy.

PubMed

Jurkić, Lela Munjas; Cepanec, Ivica; Pavelić, Sandra Kraljević; Pavelić, Krešimir

2013-01-08

Silicon (Si) is the most abundant element present in the Earth's crust besides oxygen. However, the exact biological roles of silicon remain unknown. Moreover, the ortho-silicic acid (H4SiO4), as a major form of bioavailable silicon for both humans and animals, has not been given adequate attention so far. Silicon has already been associated with bone mineralization, collagen synthesis, skin, hair and nails health atherosclerosis, Alzheimer disease, immune system enhancement, and with some other disorders or pharmacological effects. Beside the ortho-silicic acid and its stabilized formulations such as choline chloride-stabilized ortho-silicic acid and sodium or potassium silicates (e.g. M2SiO3; M= Na,K), the most important sources that release ortho-silicic acid as a bioavailable form of silicon are: colloidal silicic acid (hydrated silica gel), silica gel (amorphous silicon dioxide), and zeolites. Although all these compounds are characterized by substantial water insolubility, they release small, but significant, equilibrium concentration of ortho-silicic acid (H4SiO4) in contact with water and physiological fluids. Even though certain pharmacological effects of these compounds might be attributed to specific structural characteristics that result in profound adsorption and absorption properties, they all exhibit similar pharmacological profiles readily comparable to ortho-silicic acid effects. The most unusual ortho-silicic acid-releasing agents are certain types of zeolites, a class of aluminosilicates with well described ion(cation)-exchange properties. Numerous biological activities of some types of zeolites documented so far might probably be attributable to the ortho-silicic acid-releasing property. In this review, we therefore discuss biological and potential therapeutic effects of ortho-silicic acid and ortho-silicic acid -releasing silicon compounds as its major natural sources.

On How Fas Apoptosis-Independent Pathways Drive T Cell Hyperproliferation and Lymphadenopathy in lpr Mice.

PubMed

Balomenos, Dimitrios; Shokri, Rahman; Daszkiewicz, Lidia; Vázquez-Mateo, Cristina; Martínez-A, Carlos

2017-01-01

Fas induces massive apoptosis in T cells after repeated in vitro T cell receptor (TCR) stimulation and is critical for lymphocyte homeostasis in Fas-deficient ( lpr ) mice. Although the in vitro Fas apoptotic mechanism has been defined, there is a large conceptual gap between this in vitro phenomenon and the pathway that leads to in vivo development of lymphadenopathy and autoimmunity. A striking abnormality in lpr mice is the excessive proliferation of CD4 + and CD8 + T cells, and more so of the double-negative TCR + CD4 - CD8 - B220 + T cells. The basis of lpr T cell hyperproliferation remains elusive, as it cannot be explained by Fas-deficient apoptosis. T cell-directed p21 overexpression reduces hyperactivation/hyperproliferation of all lpr T cell subtypes and lymphadenopathy in lpr mice. p21 controls expansion of repeatedly stimulated T cells without affecting apoptosis. These results confirm a direct link between hyperactivation/hyperproliferation, autoreactivity, and lymphadenopathy in lpr mice and, with earlier studies, suggest that Fas apoptosis-independent pathways control lpr T cell hyperproliferation. lpr T cell hyperproliferation could be an indirect result of the defective apoptosis of repeatedly stimulated lpr T cells. Nonetheless, in this perspective, we argue for an alternative setting, in which lack of Fas would directly cause lpr T cell hyperactivation/hyperproliferation in vivo . We propose that Fas/Fas ligand (FasL) acts as an activation inhibitor of recurrently stimulated T cells, and that its disruption causes overexpansion of T cells in lpr mice. Research to define the underlying mechanism of this Fas/FasL effect could resolve the phenotype of lpr mice and lead to therapeutics for related human syndromes.

The Fas Ligand/Fas Death Receptor Pathways Contribute to Propofol-Induced Apoptosis and Neuroinflammation in the Brain of Neonatal Rats.

PubMed

Milanovic, Desanka; Pesic, Vesna; Loncarevic-Vasiljkovic, Natasa; Pavkovic, Zeljko; Popic, Jelena; Kanazir, Selma; Jevtovic-Todorovic, Vesna; Ruzdijic, Sabera

2016-10-01

A number of experimental studies have reported that exposure to common, clinically used anesthetics induce extensive neuroapoptosis and cognitive impairment when applied to young rodents, up to 2 weeks old, in phase of rapid synaptogenesis. Propofol is the most used general anesthetic in clinical practice whose mechanisms of neurotoxicity on the developing brain remains to be examined in depth. This study investigated effects of different exposures to propofol anesthesia on Fas receptor and Fas ligand expressions, which mediate proapoptotic and proinflammation signaling in the brain. Propofol (20 mg/kg) was administered to 7-day-old rats in multiple doses sufficient to maintain 2-, 4- and 6-h duration of anesthesia. Animals were sacrificed at 0, 4, 16 and 24 h after termination of anesthesia. It was found that propofol anesthesia induced Fas/FasL and downstream caspase-8 expression more prominently in the thalamus than in the cortex. Opposite, Bcl-2 and caspase-9, markers of intrinsic pathway activation, were shown to be more influenced by propofol treatment in the cortex. Further, we have established upregulation of caspase-1 and IL-1β cytokine transcription as well as subsequent activation of microglia that is potentially associated with brain inflammation. Behavioral analyses revealed that P35 and P60 animals, neonatally exposed to propofol, had significantly higher motor activity during three consecutive days of testing in the open field, though formation of the intersession habituation was not prevented. This data, together with our previous results, contributes to elucidation of complex mechanisms of propofol toxicity in developing brain.

Promoter hypermethylation and downregulation of the FAS gene may be involved in colorectal carcinogenesis

PubMed Central

MANOOCHEHRI, MEHDI; BORHANI, NASIM; KARBASI, ASHRAF; KOOCHAKI, AMENEH; KAZEMI, BAHRAM

2016-01-01

Aberrant DNA methylation has been investigated in carcinogenesis and as biomarker for the early detection of colorectal cancer (CRC). The present study aimed to define the methylation status in the regulatory elements of two proapoptotic genes, Fas cell surface death receptor (FAS) and BCL2-associated X protein (BAX). DNA methylation analysis was performed in tumor and adjacent normal tissue using HpaII/MspI restriction digestion and methylation-specific polymerase chain reaction (PCR). The results observed downregulation of the FAS and BAX genes in the CRC tissues compared with the adjacent normal samples. Furthermore, demethylation using 5-aza-2′-deoxycytidine treatment followed by reverse-transcription quantitative PCR were performed on the HT-29 cell line to measure BAX and FAS mRNA expression following demethylation. The 5-aza-2′-deoxycytidine treatment resulted in significant FAS gene upregulation in the HT-29 cell line, but no significant difference in BAX expression. Furthermore, analysis of CpG islands in the FAS gene promoter revealed that the FAS promoter was significantly hypermethylated in 53.3% of tumor tissues compared with adjacent normal samples. Taken together, the results indicate that decreased expression of the FAS gene due to hypermethylation of its promoter may lead to apoptotic resistance, and acts as an important step during colorectal carcinogenesis. PMID:27347139

Sterol regulatory element-binding protein-1 participates in the regulation of fatty acid synthase expression in colorectal neoplasia.

PubMed

Li, J N; Mahmoud, M A; Han, W F; Ripple, M; Pizer, E S

2000-11-25

Endogenous fatty acid synthesis has been observed in certain rapidly proliferating normal and neoplastic tissues. Sterol regulatory element-binding proteins (SREBPs) are transcription factors that regulate the expression of lipogenic genes including fatty acid synthase (FAS), the major biosynthetic enzyme for fatty acid synthesis. We have previously shown that SREBP-1, FAS, and Ki-67, a proliferation marker, colocalized in the crypts of the fetal gastrointestinal tract epithelium. This study sought to determine whether SREBP-1 participates in the regulation of proliferation-associated fatty acid synthesis in colorectal neoplasia. An immunohistochemical analysis of SREBP-1, FAS, and Ki-67 expression in 25 primary human colorectal carcinoma specimens showed colocalization in 22 of these. To elucidate a functional linkage between SREBP-1 activation and proliferation-associated FA synthesis, SREBP-1 and FAS content were assayed during the adaptive response of cultured HCT116 colon carcinoma cells to pharmacological inhibition of FA synthesis. Cerulenin and TOFA each inhibited the endogenous synthesis of fatty acids in a dose-dependent manner and each induced increases in both precursor and mature forms of SREBP-1. Subsequently, both the transcriptional activity of the FAS promoter in a luciferase reporter gene construct and the FAS expression increased. These results demonstrate that tumor cells recognize and respond to a deficiency in endogenous fatty acid synthesis by upregulating both SREBP-1 and FAS expression and support the model that SREBP-1 participates in the transcriptional regulation of lipogenic genes in colorectal neoplasia. Copyright 2000 Academic Press.

FAS 33: accurately recording effects of changing prices.

PubMed

Sage, L G

1987-02-01

FAS 33 addresses the problem of distortion in conventional historical cost financial statements because of changing prices. It requires 1300 business enterprises to report selected changing price data on a supplementary basis. It has been demonstrated that it is also feasible and beneficial for hospitals to present price disclosures as supplementary information to their financial statements. The possible application of FAS 33 is supported on the basis that the accounting and reporting methods of healthcare institutions are similar to the accounting and reporting practices of profit-seeking entities.

Possible association of FAS and FASLG polymorphisms with the risk of idiopathic azoospermia in southeast Turkey.

PubMed

Balkan, Mahmut; Atar, Murat; Erdal, Mehmet Emin; Rustemoğlu, Aydin; Yildiz, Ismail; Gunesacar, Ramazan; Hatipoğlu, Namık Kemal; Bodakçi, Mehmet Nuri; Ay, Ozlem Izci; Çevik, Kenan

2014-06-01

To investigate the association of the genetic variants of FAS/FASLG cell death pathway genes in male infertility, we genotyped the FAS -670A/G, -1377G/A, and FASLG -124A/G single-nucleotide polymorphisms (SNPs) by real-time polymerase chain reaction in 108 infertile men with idiopathic azoospermia and in 125 proven fertile controls. The distribution of genotypes and alleles for SNPs at FAS -1377G/A and FASLG -124A/G loci were determined not to be statistically different between the case and control groups. However, the genotype frequencies of SNPs, FAS -670AA and FAS -670AG, were found to be significantly different between the case and control groups. Whereas the FAS -670AA genotype might be regarded as a higher predisposition for idiopathic azoospermia, FAS -670AG could be interpreted to mean that this genotype provides protection against idiopathic azoospermia. The study of combined genotype and haplotype frequencies has found statistically significant differences between case and control subjects for some combinations. The AA-GG binary genotype for the FAS670 and FAS1377 loci couple, in particular, may have a high degree of predisposition to idiopathic azoospermia. Our results suggest that FAS -670A/G SNP may be a genetic predisposing factor of idiopathic azoospermia among southeastern Anatolian men. Larger studies are needed to verify these findings. Furthermore, our data indicated a possible linkage between the FAS and FASLG genes and idiopathic azoospermia.

7 CFR 1484.30 - How does FAS formalize its working relationship with approved Cooperators?

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 10 2010-01-01 2010-01-01 false How does FAS formalize its working relationship with... FAS formalize its working relationship with approved Cooperators? FAS will notify each applicant in... sign the program agreement and submit the signed agreement to the Director, Marketing Operations Staff...

Fas Versatile Signaling and Beyond: Pivotal Role of Tyrosine Phosphorylation in Context-Dependent Signaling and Diseases

PubMed Central

Chakrabandhu, Krittalak; Hueber, Anne-Odile

2016-01-01

The Fas/FasL system is known, first and foremost, as a potent apoptosis activator. While its proapoptotic features have been studied extensively, evidence that the Fas/FasL system can elicit non-death signals has also accumulated. These non-death signals can promote survival, proliferation, migration, and invasion of cells. The key molecular mechanism that determines the shift from cell death to non-death signals had remained unclear until the recent identification of the tyrosine phosphorylation in the death domain of Fas as the reversible signaling switch. In this review, we present the connection between the recent findings regarding the control of Fas multi-signals and the context-dependent signaling choices. This information can help explain variable roles of Fas signaling pathway in different pathologies. PMID:27799932

Local immunomodulation with Fas ligand-engineered biomaterials achieves allogeneic islet graft acceptance.

PubMed

Headen, Devon M; Woodward, Kyle B; Coronel, María M; Shrestha, Pradeep; Weaver, Jessica D; Zhao, Hong; Tan, Min; Hunckler, Michael D; Bowen, William S; Johnson, Christopher T; Shea, Lonnie; Yolcu, Esma S; García, Andrés J; Shirwan, Haval

2018-06-04

Islet transplantation is a promising therapy for type 1 diabetes. However, chronic immunosuppression to control rejection of allogeneic islets induces morbidities and impairs islet function. T effector cells are responsible for islet allograft rejection and express Fas death receptors following activation, becoming sensitive to Fas-mediated apoptosis. Here, we report that localized immunomodulation using microgels presenting an apoptotic form of the Fas ligand with streptavidin (SA-FasL) results in prolonged survival of allogeneic islet grafts in diabetic mice. A short course of rapamycin treatment boosted the immunomodulatory efficacy of SA-FasL microgels, resulting in acceptance and function of allografts over 200 days. Survivors generated normal systemic responses to donor antigens, implying immune privilege of the graft, and had increased CD4 + CD25 + FoxP3 + T regulatory cells in the graft and draining lymph nodes. Deletion of T regulatory cells resulted in acute rejection of established islet allografts. This localized immunomodulatory biomaterial-enabled approach may provide an alternative to chronic immunosuppression for clinical islet transplantation.

STARD13 promotes hepatocellular carcinoma apoptosis by acting as a ceRNA for Fas.

PubMed

Zhang, Hai; Wang, Fang; Hu, Yahua

2017-02-01

To study the roles of STARD13 in cellular apoptosis of hepatocellular carcinoma (HCC). Quantitative real-time PCR and immunohistochemistry analyses showed that the expression levels of STARD13 and Fas were lower in clinical HCC tissues than in normal tissues and were positively correlated, which is consistent with the results analyzed by The Cancer Genome Atlas (TCGA) data. Patients with higher STARD13 or Fas expression levels had longer overall survival. Additionally, STARD13 3'-UTR enhanced cellular apoptosis and the 3'-UTRs of STARD13 and Fas were predicted to harbor nine similar miRNA binding sites. And STARD13 3'-UTR promoted Fas expression in a 3'-UTR- and miRNA-dependent way and increased the sensitivity of HCC cells to chemotherapy. Importantly, the coding sequence of STARD13 did not increase Fas expression. STARD13 3'-UTR promotes HCC apoptosis through acting as a ceRNA for Fas.

Polymethylene-interrupted fatty acids: Biomarkers for native and exotic mussels in the Laurentian Great Lakes

USGS Publications Warehouse

Mezek, Tadej; Sverko, Ed; Ruddy, Martina D.; Zaruk, Donna; Capretta, Alfredo; Hebert, Craig E.; Fisk, Aaron T.; McGoldrick, Daryl J.; Newton, Teresa J.; Sutton, Trent M.; Koops, Marten A.; Muir, Andrew M.; Johnson, Timothy B.; Ebener, Mark P.; Arts, Michael T.

2011-01-01

Freshwater organisms synthesize a wide variety of fatty acids (FAs); however, the ability to synthesize and/or subsequently modify a particular FA is not universal, making it possible to use certain FAs as biomarkers. Herein we document the occurrence of unusual FAs (polymethylene-interrupted fatty acids; PMI-FAs) in select freshwater organisms in the Laurentian Great Lakes. We did not detect PMI-FAs in: (a) natural seston from Lake Erie and Hamilton Harbor (Lake Ontario), (b) various species of laboratory-cultured algae including a green alga (Scenedesmus obliquus), two cyanobacteria (Aphanizomenon flos-aquae and Synechococystis sp.), two diatoms (Asterionella formosa, Diatoma elongatum) and a chrysophyte (Dinobryon cylindricum) or, (c) zooplankton (Daphnia spp., calanoid or cyclopoid copepods) from Lake Ontario, suggesting that PMI-FAs are not substantively incorporated into consumers at the phytoplankton–zooplankton interface. However, these unusual FAs comprised 4-6% of total fatty acids (on a dry tissue weight basis) of native fat mucket (Lampsilis siliquoidea) and plain pocketbook (L. cardium) mussels and in invasive zebra (Dreissena polymorpha) and quagga (D. bugensis) mussels. We were able to clearly partition Great Lakes' mussels into three separate groups (zebra, quagga, and native mussels) based solely on their PMI-FA profiles. We also provide evidence for the trophic transfer of PMI-FAs from mussels to various fishes in Lakes Ontario and Michigan, further underlining the potential usefulness of PMI-FAs for tracking the dietary contribution of mollusks in food web and contaminant-fate studies.

Myeloperoxidase-derived 2-chlorofatty acids contribute to human sepsis mortality via acute respiratory distress syndrome.

PubMed

Meyer, Nuala J; Reilly, John P; Feng, Rui; Christie, Jason D; Hazen, Stanley L; Albert, Carolyn J; Franke, Jacob D; Hartman, Celine L; McHowat, Jane; Ford, David A

2017-12-07

Sepsis-associated acute respiratory distress syndrome (ARDS) is characterized by neutrophilic inflammation and poor survival. Since neutrophil myeloperoxidase (MPO) activity leads to increased plasma 2-chlorofatty acid (2-ClFA) levels, we hypothesized that plasma concentrations of 2-ClFAs would associate with ARDS and mortality in subjects with sepsis. In sequential consenting patients with sepsis, free 2-ClFA levels were significantly associated with ARDS, and with 30-day mortality, for each log increase in free 2-chlorostearic acid. Plasma MPO was not associated with either ARDS or 30-day mortality but was correlated with 2-ClFA levels. Addition of plasma 2-ClFA levels to the APACHE III score improved prediction for ARDS. Plasma 2-ClFA levels correlated with plasma levels of angiopoietin-2, E selectin, and soluble thrombomodulin. Endothelial cells treated with 2-ClFA responded with increased adhesion molecule surface expression, increased angiopoietin-2 release, and dose-dependent endothelial permeability. Our results suggest that 2-ClFAs derived from neutrophil MPO-catalyzed oxidation contribute to pulmonary endothelial injury and have prognostic utility in sepsis-associated ARDS.

7 CFR 1484.30 - How does FAS formalize its working relationship with approved Cooperators?

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 10 2012-01-01 2012-01-01 false How does FAS formalize its working relationship with... FOREIGN MARKETS FOR AGRICULTURAL COMMODITIES Program Operations § 1484.30 How does FAS formalize its working relationship with approved Cooperators? FAS will notify each applicant in writing of the final...

7 CFR 1484.30 - How does FAS formalize its working relationship with approved Cooperators?

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 10 2014-01-01 2014-01-01 false How does FAS formalize its working relationship with... FOREIGN MARKETS FOR AGRICULTURAL COMMODITIES Program Operations § 1484.30 How does FAS formalize its working relationship with approved Cooperators? FAS will notify each applicant in writing of the final...

7 CFR 1484.30 - How does FAS formalize its working relationship with approved Cooperators?

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 10 2013-01-01 2013-01-01 false How does FAS formalize its working relationship with... FOREIGN MARKETS FOR AGRICULTURAL COMMODITIES Program Operations § 1484.30 How does FAS formalize its working relationship with approved Cooperators? FAS will notify each applicant in writing of the final...

Apoptosis in acute shigellosis is associated with increased production of Fas/Fas ligand, perforin, caspase-1, and caspase-3 but reduced production of Bcl-2 and interleukin-2.

PubMed

Raqib, Rubhana; Ekberg, Caroline; Sharkar, Protim; Bardhan, Pradip K; Zychlinsky, Arturo; Sansonetti, Philippe J; Andersson, Jan

2002-06-01

Shigella dysenteriae type 1-induced apoptotic cell death in rectal tissues from patients infected with Shigella dysenteriae type 1 was studied by the terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling (TUNEL) technique and annexin V staining. Expression of proteins and cytokines participating in the apoptotic process (caspase-1, caspase-3, Fas [CD95], Fas ligand [Fas-L], perforin, granzyme A, Bax, WAF-1, Bcl-2, interleukin-2 [IL-2], IL-18, and granulocyte-macrophage colony-stimulating factor) in tissue in the acute and convalescent stages of dysentery was quantified at the single-cell level by in situ immunostaining. Apoptotic cell death in the lamina propria was markedly up-regulated at the acute stage (P < 0.05), where an increased number of necrotic cells were also seen. Phenotypic analysis of apoptotic cells revealed that 43% of T cells (CD3), 10% of granulocytes (CD15), and 5% of macrophages (CD56) underwent apoptosis. Increased activity of caspase-1 persisted in the rectum up to 1 month after onset. More-extensive expression of Fas, Fas-L, perforin, caspase-3, and IL-18, but not IL-2, at the acute stage than at the convalescent stage was observed. Increased expression of caspase-3 and IL-18 in tissues with severe inflammation compared to expression in those with mild inflammation was evident, implying a possible role in the perpetuation of inflammation. Significantly reduced cell death during convalescence was associated with a significant up-regulation of Bcl-2, Bax, and WAF-1 expression in the rectum compared to that in the acute phase of infection. Thus, induction of apoptosis at the local site in the early phase of S. dysenteriae type 1 infection was associated with a significant up-regulation of Fas/Fas-L and perforin and granzyme A expression and a down-regulation of Bcl-2 and IL-2, which promote cell survival.

Improved isolation and purification of functional human Fas receptor extracellular domain using baculovirus-silkworm expression system.

PubMed

Muraki, Michiro; Honda, Shinya

2011-11-01

To achieve an efficient isolation of human Fas receptor extracellular domain (hFasRECD), a fusion protein of hFasRECD with human IgG1 heavy chain Fc domain containing thrombin cleavage sequence at the junction site was overexpressed using baculovirus-silkworm larvae expression system. The hFasRECD part was separated from the fusion protein by the effective cleavage of the recognition site with bovine thrombin. Protein G column treatment of the reaction mixture and the subsequent cation-exchange chromatography provided purified hFasRECD with a final yield of 13.5mg from 25.0 ml silkworm hemolymph. The functional activity of the product was examined by size-exclusion chromatography analysis. The isolated hFasRECD less strongly interacted with human Fas ligand extracellular domain (hFasLECD) than the Fc domain-bridged counterpart, showing the contribution of antibody-like avidity in the latter case. The purified glycosylated hFasRECD presented several discrete bands in the disulphide-bridge non-reducing SDS-PAGE analysis, and virtually all of the components were considered to participate in the binding to hFasLECD. The attached glycans were susceptible to PNGase F digestion, but mostly resistant to Endo Hf digestion under denaturing conditions. One of the components exhibited a higher susceptibility to PNGase F digestion under non-denaturing conditions. Copyright © 2011 Elsevier Inc. All rights reserved.

Examining the psychometric properties of the Hindi version of Family Accommodation Scale-Self-Report (FAS-SR).

PubMed

Mahapatra, Ananya; Gupta, Rishi; Patnaik, Kuppili Pooja; Pattanaik, Raman Deep; Khandelwal, Sudhir Kumar

2017-10-01

Family accommodation (FA) is the phenomenon whereby caregivers assist or facilitate rituals or behaviours related to obsessive compulsive disorder (OCD). There is a need for a self-rated instrument to assess this construct in resource-strained clinical settings of India. To explore the factor structure of Hindi version of Family Accommodation Scale-Self Rated version (FAS-SR) and compare its validity with the gold standard Family Accommodation Scale-Interviewer Rated (FAS-IR) scale. The Hindi version of FAS-SR scale and FAS-IR scale was applied on 105 caregivers of patients with OCD. The initial factor analysis yielded three-factor models with an eigenvalue of >1 and the total variance explained by these factors was 72.017%. The internal consistency of the 19-item scale was 0.93 indicating good inter-item correlation. There was a significant positive correlation between FAS-IR scale total score and all the factors of the FAS-SR Scale. The average measure ICC was 0.889 with a 95% confidence interval from 0.783 to 0.981 (F (62,84)=37.547, p<001) indicating high degree of reliability between the Hindi version of FAS-SR and the FAS-IR scale. FAS-SR is a practical alternative to FAS-IR and has the potential to be used widely in an Indian setting. Copyright © 2017 Elsevier B.V. All rights reserved.

Release of salicylic acid, diclofenac acid and diclofenac acid salts from isotropic and anisotropic nonionic surfactant systems across rat skin.

PubMed

Gabboun, N H; Najib, N M; Ibrahim, H G; Assaf, S

2001-01-05

Release of salicylic acid, diclofenac acid, diclofenac diethylamine and diclofenac sodium, from lyotropic structured systems, namely; neat and middle liquid crystalline phases, across mid-dorsal hairless rat skin into aqueous buffer were studied. Release results were compared with those from the isotropic systems. The donor systems composed of the surfactant polyoxyethylene (20) isohexadecyl ether, HCl buffer of pH 1 or distilled water and the specific drug. High performance liquid chromatography (HPLC) methods were used to monitor the transfer of the drugs across the skin barrier. Results indicated that the rate-determining step in the transport process was the release of the drug from the specified donor system. Further, apparent zero order release was demonstrated with all systems. Except for diclofenac sodium, drug fluxes decreased as the donor medium changed from isotropic to anisotropic. The decrease in fluxes was probably due to the added constrains on the movement of drug molecules. By changing the anisotropic donor medium from neat to middle phase, drug flux decreased in case of salicylic acid and diclofenac sodium. In the mean time, flux increased in case of the diethylamine salt and appeared nearly similar in case of diclofenac acid. Rates of drug transfer across the skin from the anisotropic donors seemed to be largely controlled by the entropy contribution to the transport process. The type and extent of drug-liquid crystal interactions probably influenced the latter.

Release kinetics of esterified p-coumaric acid and ferulic acid from rice straw in mild alkaline solution.

PubMed

Linh, Tran Ngoc; Fujita, Hirokata; Sakoda, Akiyoshi

2017-05-01

The release kinetics of esterified p-coumaric acid (PCA) and ferulic acid (FA) from rice straw under a mild alkaline condition were investigated to collect fundamental data for the design of a recovery process. The results showed that the straw size, NaOH concentration, and temperature were the key parameters governing release kinetics. The analysis demonstrated that FA is released considerably faster than PCA. The close relationship between lignin and the PCA dissolution indicates a reciprocal and/or simultaneous release. Moreover, PCA is broadly distributed in the lignin network but tends to be located more densely in the lignin fraction which is not easily solubilized by alkaline treatment. In contrast, the release of FA is strongly affected by removal of lignin fraction which is easily solubilized. These results suggest that the release kinetics are controlled by the accessibility of NaOH to their ester sites in the lignin/hemicellulose network, and by their localization. Copyright © 2017 Elsevier Ltd. All rights reserved.

Control of arachidonic acid release in chick muscle cultures

NASA Technical Reports Server (NTRS)

Templeton, G. H.; Padalino, M.; Wright, W.

1985-01-01

Cultures from thigh muscles of 12 day old embryonic chicks are utilized to examine arachidonic release, prostaglandin (PG) biosynthesis, and protein synthesis. The preparation of the cultures is described. It is observed that exogenous arachidonic acid is formed into photsphatidylethanolamine and phosphatidylcholine, is released by a calcium ionosphere or phospholiphase simulator, and is the substrate for the biosynthesis of PG; the epidermal growth factor and PGF do not stimulate protein synthesis over the basal levels. The relationship between arachidonate release and melittin is studied. The data reveal that a change in intracellular calcium stimulates phospholiphase activity, arachidonate release, and PG synthesis in chick muscle culture.

Omega-3 fatty acids prevent inflammation and metabolic disorder through inhibition of NLRP3 inflammasome activation.

PubMed

Yan, Yiqing; Jiang, Wei; Spinetti, Thibaud; Tardivel, Aubry; Castillo, Rosa; Bourquin, Carole; Guarda, Greta; Tian, Zhigang; Tschopp, Jurg; Zhou, Rongbin

2013-06-27

Omega-3 fatty acids (ω-3 FAs) have potential anti-inflammatory activity in a variety of inflammatory human diseases, but the mechanisms remain poorly understood. Here we show that stimulation of macrophages with ω-3 FAs, including eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and other family members, abolished NLRP3 inflammasome activation and inhibited subsequent caspase-1 activation and IL-1β secretion. In addition, G protein-coupled receptor 120 (GPR120) and GPR40 and their downstream scaffold protein β-arrestin-2 were shown to be involved in inflammasome inhibition induced by ω-3 FAs. Importantly, ω-3 FAs also prevented NLRP3 inflammasome-dependent inflammation and metabolic disorder in a high-fat-diet-induced type 2 diabetes model. Our results reveal a mechanism through which ω-3 FAs repress inflammation and prevent inflammation-driven diseases and suggest the potential clinical use of ω-3 FAs in gout, autoinflammatory syndromes, or other NLRP3 inflammasome-driven inflammatory diseases. Copyright © 2013 Elsevier Inc. All rights reserved.

The effect of a low essential fatty acid diet on hibernation in marmots.

PubMed

Florant, G L; Hester, L; Ameenuddin, S; Rintoul, D A

1993-04-01

We investigated the effect of an essential fatty acid (EFA)-deficient diet on hibernation patterns in yellow-bellied marmots (Marmota flaviventris). Fatty acid (FA) analysis of white adipose tissue (WAT) from animals maintained for 2 mo on the EFA-deficient diet suggested that little or no EFAs were present in the gonadal or omental fat depots. Hibernation about lengths of the EFA-deficient animals were significantly shorter (P < 0.01) than control animals. Stated another way, these animals aroused twice as frequently compared with control animals and used more energy to survive winter. Analysis of WAT composition and blood samples revealed that animals were highly lipolytic during winter. Furthermore, the release of FAs was not random: linoleate (cis-9,cis-12-octadecadienoic acid; 18:2, a diene EFA) was significantly (P < 0.05) under-represented in venous outflow from the gonadal WAT pad based on the percentage of this species in WAT. The concentration of saturated FAs was higher than that predicted from the WAT-FA composition. We conclude that linoleate is preferentially retained within WAT and that concentrations of this EFA may influence hibernation behavior. Thus EFAs may have a thermoregulatory role in hibernation in addition to their role as essential precursors for physiologically important lipids after hibernation is over.

Increased hepatocyte fas expression and apoptosis in HIV and hepatitis C virus coinfection.

PubMed

Macias, Juan; Japón, Miguel A; Sáez, Carmen; Palacios, Rosa B; Mira, José A; García-García, José A; Merchante, Nicolás; Vergara, Salvador; Lozano, Fernando; Gómez-Mateos, Jesús; Pineda, Juan A

2005-11-01

Chronic hepatitis C disease (CHC) follows an accelerated course in human immunodeficiency virus (HIV) coinfection. The reasons for this are unclear. Fas-mediated hepatocyte apoptosis is involved in the pathogenesis of hepatitis C virus (HCV) infection. We sought to compare the expression of Fas on hepatocytes and irreversible apoptosis of hepatocytes among patients with CHC with and without HCV/HIV coinfection. Fas-immunostained hepatocytes were semiquantified, and apoptotic hepatocytes were detected by staining caspase-cleaved cytokeratin 18 filaments and counted across the entire section of liver-biopsy specimens from HCV-infected patients with and without HCV/HIV coinfection. One hundred thirty-four HCV/HIV-coinfected and 100 HCV-infected patients were included. HCV/HIV coinfection was associated with both diffuse distribution of Fas-stained hepatocytes (adjusted odds ratio [AOR], 7.4 [95% confidence interval {CI}, 3.8-14.4]) and with apoptotic hepatocyte counts greater than the median (AOR, 2.5 [95% CI, 1.5-4.5]). In HCV/HIV-coinfected patients, CD4+ cell nadir<200 cells/mL was associated with both Fas expression (AOR, 2.9 [95% CI, 1.3-6.8]) and hepatocyte apoptosis (AOR, 2.3 [95% CI, 1.1-4.9]). HCV/HIV-coinfected patients show higher levels of hepatocytes expressing Fas and undergoing irreversible apoptosis than do HCV-infected patients. However, low CD4+ cell nadirs in coinfected patients are associated with hepatocyte Fas expression and apoptosis.

FAS apoptotic inhibitory molecule 2 is a stress-induced intrinsic neuroprotective factor in the retina.

PubMed

Pawar, Mercy; Busov, Boris; Chandrasekhar, Aaruran; Yao, Jingyu; Zacks, David N; Besirli, Cagri G

2017-10-01

We report the neuroprotective role of FAS apoptotic inhibitory molecule 2 (FAIM2), an inhibitor of the FAS signaling pathway, during stress-induced photoreceptor apoptosis. Retinal detachment resulted in increased FAIM2 levels in photoreceptors with higher amounts detected at the tips of outer segments. Activation of FAS death receptor via FAS-ligand led to JNK-mediated FAIM2 phosphorylation, decreased proteasome-mediated degradation and increased association with the FAS receptor. Photoreceptor apoptosis was accelerated in Faim2 knockout mice following experimental retinal detachment. We show that FAIM2 is primarily involved in reducing stress-induced photoreceptor cell death but this effect was transient. FAIM2 was found to interact with both p53 and HSP90 following the activation of the FAS death pathway and FAIM2/HSP90 interaction was dependent on the phosphorylation of FAIM2. Lack of FAIM2 led to increased expression of proadeath genes Fas and Ripk1 in the retina under physiologic conditions. These results demonstrate that FAIM2 is an intrinsic neuroprotective factor activated by stress in photoreceptors and delays FAS-mediated photoreceptor apoptosis. Modulation of this pathway to increase FAIM2 expression may be a potential therapeutic option to prevent photoreceptor death.

H3K9 Trimethylation Silences Fas Expression to Confer Colon Carcinoma Immune Escape and 5-Fluorouracil Chemoresistance

PubMed Central

Paschall, Amy V.; Yang, Dafeng; Lu, Chunwan; Choi, Jeong-Hyeon; Li, Xia; Liu, Feiyan; Figueroa, Mario; Oberlies, Nicholas H.; Pearce, Cedric; Bollag, Wendy B.; Nayak-Kapoor, Asha; Liu, Kebin

2015-01-01

The Fas-FasL effector mechanism plays a key role in cancer immune surveillance by host T cells, but metastatic human colon carcinoma often uses silencing Fas expression as a mechanism of immune evasion. The molecular mechanism under FAS transcriptional silencing in human colon carcinoma is unknown. We performed genome-wide ChIP-Sequencing analysis and identified that the FAS promoter is enriched with H3K9me3 in metastatic human colon carcinoma cells. H3K9me3 level in the FAS promoter region is significantly higher in metastatic than in primary cancer cells, and is inversely correlated with Fas expression level. We discovered that verticillin A is a selective inhibitor of histone methyltransferases SUV39H1, SUV39H2 and G9a/GLP that exhibit redundant functions in H3K9 trimethylation and FAS transcriptional silencing. Genome-wide gene expression analysis identified FAS as one of the verticillin A target genes. Verticillin A treatment decreased H3K9me3 level in the FAS promoter and restored Fas expression. Furthermore, verticillin A exhibited greater efficacy than Decitabine and Vorinostat in overcoming colon carcinoma resistance to FasL-induced apoptosis. Verticillin A also increased DR5 expression and overcame colon carcinoma resistance to DR5 agonist drozitumab-induced apoptosis. Interestingly, verticillin A overcame metastatic colon carcinoma resistance to 5-Fluouracil in vitro and in vivo. Using an orthotopic colon cancer mouse model, we demonstrated that tumor-infiltrating cytotoxic T lymphocytes are FasL+ and FasL-mediated cancer immune surveillance is essential for colon carcinoma growth control in vivo. Our findings determine that H3K9me3 of the FAS promoter is a dominant mechanism underlying FAS silencing and resultant colon carcinoma immune evasion and progression. PMID:26136424

Poly (lactic-co-glycolic acid) controlled release systems: experimental and modeling insights

PubMed Central

Hines, Daniel J.; Kaplan, David L.

2013-01-01

Poly-lactic-co-glycolic acid (PLGA) has been the most successful polymeric biomaterial for use in controlled drug delivery systems. There are several different chemical and physical properties of PLGA that impact the release behavior of drugs from PLGA delivery devices. These properties must be considered and optimized in drug release device formulation. Mathematical modeling is a useful tool for identifying, characterizing, and predicting the mechanisms of controlled release. The advantages and limitations of poly (lactic-co-glycolic acid) for controlled release are reviewed, followed by a review of current approaches in controlled release technology that utilize PLGA. Mathematical modeling applied towards controlled release rates from PLGA-based devices will also be discussed to provide a complete picture of state of the art understanding of the control achievable with this polymeric system, as well as the limitations. PMID:23614648

Drosophila fatty acid taste signals through the PLC pathway in sugar-sensing neurons.

PubMed

Masek, Pavel; Keene, Alex C

2013-01-01

Taste is the primary sensory system for detecting food quality and palatability. Drosophila detects five distinct taste modalities that include sweet, bitter, salt, water, and the taste of carbonation. Of these, sweet-sensing neurons appear to have utility for the detection of nutritionally rich food while bitter-sensing neurons signal toxicity and confer repulsion. Growing evidence in mammals suggests that taste for fatty acids (FAs) signals the presence of dietary lipids and promotes feeding. While flies appear to be attracted to fatty acids, the neural basis for fatty acid detection and attraction are unclear. Here, we demonstrate that a range of FAs are detected by the fly gustatory system and elicit a robust feeding response. Flies lacking olfactory organs respond robustly to FAs, confirming that FA attraction is mediated through the gustatory system. Furthermore, flies detect FAs independent of pH, suggesting the molecular basis for FA taste is not due to acidity. We show that low and medium concentrations of FAs serve as an appetitive signal and they are detected exclusively through the same subset of neurons that sense appetitive sweet substances, including most sugars. In mammals, taste perception of sweet and bitter substances is dependent on phospholipase C (PLC) signaling in specialized taste buds. We find that flies mutant for norpA, a Drosophila ortholog of PLC, fail to respond to FAs. Intriguingly, norpA mutants respond normally to other tastants, including sucrose and yeast. The defect of norpA mutants can be rescued by selectively restoring norpA expression in sweet-sensing neurons, corroborating that FAs signal through sweet-sensing neurons, and suggesting PLC signaling in the gustatory system is specifically involved in FA taste. Taken together, these findings reveal that PLC function in Drosophila sweet-sensing neurons is a conserved molecular signaling pathway that confers attraction to fatty acids.

Chloral Hydrate Treatment Induced Apoptosis of Macrophages via Fas Signaling Pathway.

PubMed

Cai, Jun; Peng, Yanxia; Chen, Ting; Liao, Huanjin; Zhang, Lifang; Chen, Qiuhua; He, Yiming; Wu, Ping; Xie, Tong; Pan, Qingjun

2016-12-10

BACKGROUND There are recent reports on several anesthetics that have anti-inflammatory and anti-infective effects apart from their uses for pain relief and muscle relaxation. Chloral hydrate is a clinical anesthetic drug and sedative that has also been reported to attenuate inflammatory response, but the mechanisms are not clearly understood. MATERIAL AND METHODS This study investigated the effect of chloral hydrate treatment on the apoptosis of macrophages and explored the underlying mechanisms. RAW264.7 macrophages were treated with various concentrations of chloral hydrate for various lengths of time. Morphological changes were observed under a light microscope and apoptosis was detected with annexin-V-FITC/PI double-staining assay, Hochest 33258 and DNA ladder assay, the expression of Fas/FasL was detected with a flow cytometer, and the Fas signaling pathway was assessed by Western blotting. RESULTS The results showed that chloral hydrate treatment induced the morphology of RAW264.7 macrophages to change shape from typical fusiform to round in a concentration- and time-dependent manner, and was finally suspended in the supernatant. For the induction of apoptosis, chloral hydrate treatment induced the apoptosis of RAW264.7 macrophages from early-to-late stage apoptosis in a concentration- and time-dependent manner. For the mechanism, chloral hydrate treatment induced higher expression of Fas on RAW264.7 macrophages, and was also associated with changes in the expression of proteins involved in Fas signaling pathways. CONCLUSIONS Chloral hydrate treatment can induce the apoptosis of RAW264.7 macrophages through the Fas signaling pathway, which may provide new options for adjunctive treatment of acute inflammation.

Chloral Hydrate Treatment Induced Apoptosis of Macrophages via Fas Signaling Pathway

PubMed Central

Cai, Jun; Peng, Yanxia; Chen, Ting; Liao, Huanjin; Zhang, Lifang; Chen, Qiuhua; He, Yiming; Wu, Ping; Xie, Tong; Pan, Qingjun

2016-01-01

Background There are recent reports on several anesthetics that have anti-inflammatory and anti-infective effects apart from their uses for pain relief and muscle relaxation. Chloral hydrate is a clinical anesthetic drug and sedative that has also been reported to attenuate inflammatory response, but the mechanisms are not clearly understood. Material/Methods This study investigated the effect of chloral hydrate treatment on the apoptosis of macrophages and explored the underlying mechanisms. RAW264.7 macrophages were treated with various concentrations of chloral hydrate for various lengths of time. Morphological changes were observed under a light microscope and apoptosis was detected with annexin-V-FITC/PI double-staining assay, Hochest 33258 and DNA ladder assay, the expression of Fas/FasL was detected with a flow cytometer, and the Fas signaling pathway was assessed by Western blotting. Results The results showed that chloral hydrate treatment induced the morphology of RAW264.7 macrophages to change shape from typical fusiform to round in a concentration- and time-dependent manner, and was finally suspended in the supernatant. For the induction of apoptosis, chloral hydrate treatment induced the apoptosis of RAW264.7 macrophages from early-to-late stage apoptosis in a concentration- and time-dependent manner. For the mechanism, chloral hydrate treatment induced higher expression of Fas on RAW264.7 macrophages, and was also associated with changes in the expression of proteins involved in Fas signaling pathways. Conclusions Chloral hydrate treatment can induce the apoptosis of RAW264.7 macrophages through the Fas signaling pathway, which may provide new options for adjunctive treatment of acute inflammation. PMID:27941708

Changes in membrane lipids drive increased endocytosis following Fas ligation.

PubMed

Degli Esposti, Mauro; Matarrese, Paola; Tinari, Antonella; Longo, Agostina; Recalchi, Serena; Khosravi-Far, Roya; Malorni, Walter; Misasi, Roberta; Garofalo, Tina; Sorice, Maurizio

2017-05-01

Once activated, some surface receptors promote membrane movements that open new portals of endocytosis, in part to facilitate the internalization of their activated complexes. The prototypic death receptor Fas (CD95/Apo1) promotes a wave of enhanced endocytosis that induces a transient intermixing of endosomes with mitochondria in cells that require mitochondria to amplify death signaling. This initiates a global alteration in membrane traffic that originates from changes in key membrane lipids occurring in the endoplasmic reticulum (ER). We have focused the current study on specific lipid changes occurring early after Fas ligation. We analyzed the interaction between endosomes and mitochondria in Jurkat T cells by nanospray-Time-of-flight (ToF) Mass Spectrometry. Immediately after Fas ligation, we found a transient wave of lipid changes that drives a subpopulation of early endosomes to merge with mitochondria. The earliest event appears to be a decrease of phosphatidylcholine (PC), linked to a metabolic switch enhancing phosphatidylinositol (PI) and phosphoinositides, which are crucial for the formation of vacuolar membranes and endocytosis. Lipid changes occur independently of caspase activation and appear to be exacerbated by caspase inhibition. Conversely, inhibition or compensation of PC deficiency attenuates endocytosis, endosome-mitochondria mixing and the induction of cell death. Deficiency of receptor interacting protein, RIP, also limits the specific changes in membrane lipids that are induced by Fas activation, with parallel reduction of endocytosis. Thus, Fas activation rapidly changes the interconversion of PC and PI, which then drives enhanced endocytosis, thus likely propagating death signaling from the cell surface to mitochondria and other organelles.

Amino Acid Transporters and Release of Hydrophobic Amino Acids in the Heterocyst-Forming Cyanobacterium Anabaena sp. Strain PCC 7120.

PubMed

Pernil, Rafael; Picossi, Silvia; Herrero, Antonia; Flores, Enrique; Mariscal, Vicente

2015-04-23

Anabaena sp. strain PCC 7120 is a filamentous cyanobacterium that can use inorganic compounds such as nitrate or ammonium as nitrogen sources. In the absence of combined nitrogen, it can fix N2 in differentiated cells called heterocysts. Anabaena also shows substantial activities of amino acid uptake, and three ABC-type transporters for amino acids have been previously characterized. Seven new loci encoding predicted amino acid transporters were identified in the Anabaena genomic sequence and inactivated. Two of them were involved in amino acid uptake. Locus alr2535-alr2541 encodes the elements of a hydrophobic amino acid ABC-type transporter that is mainly involved in the uptake of glycine. ORF all0342 encodes a putative transporter from the dicarboxylate/amino acid:cation symporter (DAACS) family whose inactivation resulted in an increased uptake of a broad range of amino acids. An assay to study amino acid release from Anabaena filaments to the external medium was set up. Net release of the alanine analogue α-aminoisobutyric acid (AIB) was observed when transport system N-I (a hydrophobic amino acid ABC-type transporter) was engaged in the uptake of a specific substrate. The rate of AIB release was directly proportional to the intracellular AIB concentration, suggesting leakage from the cells by diffusion.

[Plasma fatty acids profile and lipids in Tunisian male elite athletes].

PubMed

Omar, Souheil; Sethom, Mohamed M; Feki-Mhiri, Sondes; Hadj-Taeib, Sameh; Ben Ayed, Ikram; Feki, Moncef; Kaabachi, Naziha

2010-05-01

Growing interest is accorded to polyunsaturated fatty acids (PUFAs) omega3, which are considered beneficial for health. to investigate the effect of sports on plasma lipids and fatty acids (FAs), especially omega6 and omega3 PUFAs and the omega6/omega3 ratio. The study included 75 Tunisian male elite athletes, practicing team sport and 70 sedentary healthy men as controls. Plasma FAs profile was analyzed by gas chromatography. Comparison between groups was performed using a univariate GLM analysis, with adjustment on age, body mass and energy intake. Athletes showed lower triglycerides and saturated FAs (27.64% +/- 2.17% vs. 30.41% +/- 4.35%) and increased HDL cholesterol and monounsaturated FAs (21.19% +/- 2 44% vs. 19.12% +/- 3.03%). However, there was no significant difference in total PUFAs, omega6 and omega3 families and omega6/omega3 ratio (10.15% +/- 3.24% vs. 10.20% +/- 3.37%) between athletes and sedentary. Sport favorably modifies the profile of plasma FAs by increasing monounsaturated FAs at the expense of saturated FAs, but has no effect on total PUFAs, and omega6 and omega3 families. A diet rich in omega3 PUFAs would lower the omega6/omega3 ratio, in order to improve the health and probably the performance of athletes.

Proteases in Fas-mediated apoptosis.

PubMed

Zhivotovsky, B; Burgess, D H; Schlegel, J; Pörn, M I; Vanags, D; Orrenius, S

1997-01-01

Involvement of a unique family of cysteine proteases in the multistep apoptotic process has been documented. Cloning of several mammalian genes identifies some components of this cellular response. However, it is currently unclear which protease plays a role as a signal and/or effector of apoptosis. We summarize contributions to the data concerning proteases in Fas-mediated apoptosis.

Acid-Labile Acyclic Cucurbit[n]uril Molecular Containers for Controlled Release.

PubMed

Mao, Dake; Liang, Yajun; Liu, Yamin; Zhou, Xianhao; Ma, Jiaqi; Jiang, Biao; Liu, Jia; Ma, Da

2017-10-02

Stimuli-responsive molecular containers are of great importance for controlled drug delivery and other biomedical applications. A new type of acid labile acyclic cucurbit[n]uril (CB[n]) molecular containers is presented that can degrade and release the encapsulated cargo at accelerated rates under mildly acidic conditions (pH 5.5-6.5). These containers retain the excellent recognition properties of CB[n]-type hosts. A cell culture study demonstrated that the cellular uptake of cargos could be fine-tuned by complexation with different containers. The release and cell uptake of cargo dye was promoted by acidic pH. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

LncRNA FAS-AS1 promotes the degradation of extracellular matrix of cartilage in osteoarthritis.

PubMed

Zhu, J-K; He, T-D; Wei, Z-X; Wang, Y-M

2018-05-01

To investigate the expression of long non-coding RNA (lncRNA) FAS-AS1 in osteoarthritis cartilage and to explore its effect on articular cartilage cells. A total of 20 tissue samples of primary knee joint osteoarthritis and 20 tissue samples of knee joint cartilage after traumatic amputation were collected. Fluorescence quantitative polymerase chain reaction (PCR) was performed to detect the expression of FAS-AS1, MMP1, MMP13, and COL2A1 in cartilage. FAS-AS1 small interfering RNA (siRNA) was transfected to chondrocytes transiently to observe its effects on proliferation, apoptosis of chondrocytes, and the expressions of MMP1, MMP13, and COL2A1. The expressions of FAS-AS1, MMP1, and MMP13 in osteoarthritis tissues increased significantly, while COL2A1 presented a low expression. Reducing the expression of FAS-AS1 inhibited cell apoptosis and promote cell proliferation. Additionally, in vitro experiments showed that low expression of FAS-AS1 decreased the expressions of MMP1 and MMP13, but increased the expression of COL2A1. The expression of FAS-AS1 was increased in osteoarthritis, and FAS-AS1 could be involved in the development of the disease by regulating the proliferation, apoptosis of chondrocytes and promoting the degradation of extracellular matrix.

Transfection of apoptosis related gene Fas ligand in human hepatocellular carcinoma cells and its significance in apoptosis

PubMed Central

Chen, Jun; Su, Xian-Shi; Jiang, Yong-Fang; Gong, Guo-Zhong; Zheng, Yu-Huang; Li, Gui-Yuan

2005-01-01

AIM: To evaluate the expression of apoptosis related gene Fas ligand (FasL) in human hepatocellular carcinoma (HCC) cells HepG2 and its significance in apoptosis. METHODS: Levels of soluble Fas ligand (sFasL) in a group of patients with hepatitis B virus (HBV)-induced chronic hepatitis, HBV-positive liver cirrhosis and HCC were evaluated. In a further study, the recombinant eukaryotic expression plasmid pcDNA3.1hisB-FasL was transfected into HCC cells HepG2 by lipofection, and then soluble FasL was examined in the supernatant of culture cells by EIA, FasL expression in HepG2 cells was detected by immuohistochemistry. After being stained by annexin V and propidium iodine, cells were passed through a flow cytometer and examined by a fluorescence microscope and a laser scanning microscope. RESULTS: The sFasL levels were significantly lower in patients with HCC when compared to the patients with hepatitis or liver cirrhosis. In comparison with untransfected cells, the soluble FasL could be detected in the supernatant of transfected cells. FasL was expressed on the membranes and cytoplasm of transfected cells. The apoptotic cell rate was 36.30% in transfected cells, and was 11.53% in untransfected cells. Moreover, the different stage of apoptotic cells could be distinguished by annexin V and propidium iodine staining. CONCLUSION: Fas ligand is an apoptotic pathway of HCC cells. PMID:15849828

Crystal Structure of the Complex of Human FasL and Its Decoy Receptor DcR3.

PubMed

Liu, Weifeng; Ramagopal, Udupi; Cheng, Huiyong; Bonanno, Jeffrey B; Toro, Rafael; Bhosle, Rahul; Zhan, Chenyang; Almo, Steven C

2016-11-01

The apoptotic effect of FasL:Fas signaling is disrupted by DcR3, a unique secreted member of the tumor necrosis factor receptor superfamily, which also binds and neutralizes TL1A and LIGHT. DcR3 is highly elevated in patients with various tumors and contributes to mechanisms by which tumor cells to evade host immune surveillance. Here we report the crystal structure of FasL in complex with DcR3. Comparison of FasL:DcR3 structure with our earlier TL1A:DcR3 and LIGHT:DcR3 structures supports a paradigm involving the recognition of invariant main-chain and conserved side-chain functionalities, which is responsible for the recognition of multiple TNF ligands exhibited by DcR3. The FasL:DcR3 structure also provides insight into the FasL:Fas recognition surface. We demonstrate that the ability of recombinant FasL to induce Jurkat cell apoptosis is significantly enhanced by native glycosylation or by structure-inspired mutations, both of which result in reduced tendency to aggregate. All of these activities are efficiently inhibited by recombinant DcR3. Copyright © 2016 Elsevier Ltd. All rights reserved.

Association of cytosolic sialidase Neu2 with plasma membrane enhances Fas-mediated apoptosis by impairing PI3K-Akt/mTOR-mediated pathway in pancreatic cancer cells.

PubMed

Nath, Shalini; Mandal, Chhabinath; Chatterjee, Uttara; Mandal, Chitra

2018-02-12

Modulation of sialylation by sialyltransferases and sialidases plays essential role in carcinogenesis. There are few reports on sialyltransferase, however, the contribution of cytosolic sialidase (Neu2) remains unexplored in pancreatic ductal adenocarcinoma (PDAC). We observed lower expression of Neu2 in different PDAC cells, patient tissues, and a significant strong association with clinicopathological characteristics. Neu2 overexpression guided drug-resistant MIAPaCa2 and AsPC1 cells toward apoptosis as evidenced by decreased Bcl2/Bax ratio, activation of caspase-3/caspase-6/caspase-8, PARP reduction, reduced CDK2/CDK4/CDK6, and cyclin-B1/cyclin-E with unaffected caspase-9. Neu2-overexpressed cells exhibited higher expression of Fas/CD95-death receptor, FasL, FADD, and Bid cleavage confirming extrinsic pathway-mediated apoptosis. α2,6-linked sialylation of Fas helps cancer cells to survive, which is a substrate for Neu2. Therefore, their removal should enhance Fas-mediated apoptosis. Neu2-overexpressed cells indeed showed increased enzyme activity even on membrane. Interestingly, this membrane-bound Neu2 exhibited enhanced association with Fas causing its desialylation and activation as corroborated by decreased association of Fas with α2,6-sialic acid-binding lectin. Additionally, enhanced cytosolic Neu2 inhibited the expression of several growth factor-mediated signaling molecules involved in PI3K/Akt-mTOR pathway probably through desialylation which in turn also causes Fas activation. Furthermore, Neu2-overexpressed cells exhibited reduced cell migration, invasion with decreased VEGF, VEGFR, and MMP9 levels. To the best of our knowledge, this is the first report of cytosolic Neu2 on membrane, its association with Fas, enhanced desialylation, activation, and Fas-mediated apoptosis. Taken together, our study ascertains a novel concept by which the function of Fas/CD95 could be modulated indicating a critical role of upstream Neu2 as a promising target for

Defects in Mitochondrial Fatty Acid Synthesis Result in Failure of Multiple Aspects of Mitochondrial Biogenesis in Saccharomyces cerevisiae

PubMed Central

Kursu, V. A. Samuli; Pietikäinen, Laura P.; Fontanesi, Flavia; Aaltonen, Mari J.; Suomi, Fumi; Nair, Remya Raghavan; Schonauer, Melissa S.; Dieckmann, Carol L.; Barrientos, Antoni; Hiltunen, J. Kalervo; Kastaniotis, Alexander J.

2014-01-01

Summary Mitochondrial fatty acid synthesis (mtFAS) shares acetyl-CoA with the Krebs cycle as a common substrate and is required for the production of octanoic acid (C8) precursors of lipoic acid (LA) in mitochondria. MtFAS is a conserved pathway essential for respiration. In a genetic screen in Saccharomyces cerevisiae designed to further elucidate the physiological role of mtFAS, we isolated mutants with defects in mitochondrial post-translational gene expression processes, indicating a novel link to mitochondrial gene expression and respiratory chain biogenesis. In our ensuing analysis, we show that mtFAS, but not lipoylation per se, is required for respiratory competence. We demonstrate that mtFAS is required for mRNA splicing, mitochondrial translation and respiratory complex assembly, and provide evidence that not LA per se, but fatty acids longer than C8 play a role in these processes. We also show that mtFAS- and LA-deficient strains suffer from a mild heme deficiency that may contribute to the respiratory complex assembly defect. Based on our data and previously published information, we propose a model implicating mtFAS as a sensor for mitochondrial acetyl-CoA availability and a coordinator of nuclear and mitochondrial gene expression by adapting the mitochondrial compartment to changes in the metabolic status of the cell. PMID:24102902

Defects in mitochondrial fatty acid synthesis result in failure of multiple aspects of mitochondrial biogenesis in Saccharomyces cerevisiae.

PubMed

Kursu, V A Samuli; Pietikäinen, Laura P; Fontanesi, Flavia; Aaltonen, Mari J; Suomi, Fumi; Raghavan Nair, Remya; Schonauer, Melissa S; Dieckmann, Carol L; Barrientos, Antoni; Hiltunen, J Kalervo; Kastaniotis, Alexander J

2013-11-01

Mitochondrial fatty acid synthesis (mtFAS) shares acetyl-CoA with the Krebs cycle as a common substrate and is required for the production of octanoic acid (C8) precursors of lipoic acid (LA) in mitochondria. MtFAS is a conserved pathway essential for respiration. In a genetic screen in Saccharomyces cerevisiae designed to further elucidate the physiological role of mtFAS, we isolated mutants with defects in mitochondrial post-translational gene expression processes, indicating a novel link to mitochondrial gene expression and respiratory chain biogenesis. In our ensuing analysis, we show that mtFAS, but not lipoylation per se, is required for respiratory competence. We demonstrate that mtFAS is required for mRNA splicing, mitochondrial translation and respiratory complex assembly, and provide evidence that not LA per se, but fatty acids longer than C8 play a role in these processes. We also show that mtFAS- and LA-deficient strains suffer from a mild haem deficiency that may contribute to the respiratory complex assembly defect. Based on our data and previously published information, we propose a model implicating mtFAS as a sensor for mitochondrial acetyl-CoA availability and a co-ordinator of nuclear and mitochondrial gene expression by adapting the mitochondrial compartment to changes in the metabolic status of the cell. © 2013 John Wiley & Sons Ltd.

The preparation and the sustained release of titanium dioxide hollow particles encapsulating L-ascorbic acid

NASA Astrophysics Data System (ADS)

Tominaga, Yoko; Kadota, Kazunori; Shimosaka, Atsuko; Yoshida, Mikio; Oshima, Kotaro; Shirakawa, Yoshiyuki

2018-05-01

The preparation of the titanium dioxide hollow particles encapsulating L-ascorbic acid via sol-gel process using inkjet nozzle has been performed, and the sustained release and the effect protecting against degradation of L-ascorbic acid in the particles were investigated. The morphology of titanium dioxide particles was evaluated by scanning electron microscopy (SEM) and energy dispersive X-ray spectrometry (EDS). The sustained release and the effect protecting against degradation of L-ascorbic acid were estimated by dialysis bag method in phosphate buffer saline (PBS) (pH = 7.4) as release media. The prepared titanium dioxide particles exhibited spherical porous structures. The particle size distribution of the titanium dioxide particles was uniform. The hollow titanium dioxide particles encapsulating L-ascorbic acid showed the sustained release. It was also found that the degradation of L-ascorbic acid could be inhibited by encapsulating L-ascorbic acid in the titanium dioxide hollow particles.

Apoptosis in Acute Shigellosis Is Associated with Increased Production of Fas/Fas Ligand, Perforin, Caspase-1, and Caspase-3 but Reduced Production of Bcl-2 and Interleukin-2

PubMed Central

Raqib, Rubhana; Ekberg, Caroline; Sharkar, Protim; Bardhan, Pradip K.; Zychlinsky, Arturo; Sansonetti, Philippe J.; Andersson, Jan

2002-01-01

Shigella dysenteriae type 1-induced apoptotic cell death in rectal tissues from patients infected with Shigella dysenteriae type 1 was studied by the terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling (TUNEL) technique and annexin V staining. Expression of proteins and cytokines participating in the apoptotic process (caspase-1, caspase-3, Fas [CD95], Fas ligand [Fas-L], perforin, granzyme A, Bax, WAF-1, Bcl-2, interleukin-2 [IL-2], IL-18, and granulocyte-macrophage colony-stimulating factor) in tissue in the acute and convalescent stages of dysentery was quantified at the single-cell level by in situ immunostaining. Apoptotic cell death in the lamina propria was markedly up-regulated at the acute stage (P < 0.05), where an increased number of necrotic cells were also seen. Phenotypic analysis of apoptotic cells revealed that 43% of T cells (CD3), 10% of granulocytes (CD15), and 5% of macrophages (CD56) underwent apoptosis. Increased activity of caspase-1 persisted in the rectum up to 1 month after onset. More-extensive expression of Fas, Fas-L, perforin, caspase-3, and IL-18, but not IL-2, at the acute stage than at the convalescent stage was observed. Increased expression of caspase-3 and IL-18 in tissues with severe inflammation compared to expression in those with mild inflammation was evident, implying a possible role in the perpetuation of inflammation. Significantly reduced cell death during convalescence was associated with a significant up-regulation of Bcl-2, Bax, and WAF-1 expression in the rectum compared to that in the acute phase of infection. Thus, induction of apoptosis at the local site in the early phase of S. dysenteriae type 1 infection was associated with a significant up-regulation of Fas/Fas-L and perforin and granzyme A expression and a down-regulation of Bcl-2 and IL-2, which promote cell survival. PMID:12011015

Association of total marine fatty acids, eicosapentaenoic and docosahexaenoic acids, with aortic stiffness in Koreans, whites, and Japanese Americans.

PubMed

Sekikawa, Akira; Shin, Chol; Masaki, Kamal H; Barinas-Mitchell, Emma J M; Hirooka, Nobutaka; Willcox, Bradley J; Choo, Jina; White, Jessica; Evans, Rhobert W; Fujiyoshi, Akira; Okamura, Tomonori; Miura, Katsuyuki; Muldoon, Matthew F; Ueshima, Hirotsugu; Kuller, Lewis H; Sutton-Tyrrell, Kim

2013-11-01

Few previous studies have reported the association of aortic stiffness with marine n-3 fatty acids (Fas) in the general population. The aim of this study was to determine the combined and independent associations of 2 major marine n-3 FAs, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), with aortic stiffness evaluated using carotid-femoral pulse wave velocity (cfPWV) in Korean, white, and Japanese American men. A population-based sample of 851 middle-aged men (299 Koreans, 266 whites, and 286 Japanese Americans) was examined for cfPWV during 2002-2006. Serum FAs, including EPA and DHA, were measured as a percentage of total FAs using gas chromatography. Multiple regression analysis was used to examine the association of EPA and DHA with cfPWV after adjusting for blood pressure and other confounders. Mean EPA and DHA levels were 1.9 (SD = 1.0) and 4.8 (SD = 1.4) for Koreans, 0.8 (SD = 0.6) and 2.4 (SD = 1.2) for whites, and 1.0 (SD = 1.0) and 3.2 (SD = 1.4) for Japanese Americans. Both EPA and DHA were significantly higher in Koreans than in the other 2 groups (P < 0.01). Multiple regression analyses in Koreans showed that cfPWV had a significant inverse association with total marine n-3 FAs and with EPA alone after adjusting for blood pressure and other potential confounders. In contrast, there was no significant association of cfPWV with DHA. Whites and Japanese Americans did not show any significant associations of cfPWV with total marine n-3 FAs, EPA, or DHA. High levels of EPA observed in Koreans have an inverse association with aortic stiffness. © American Journal of Hypertension, Ltd 2013. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Association of Total Marine Fatty Acids, Eicosapentaenoic and Docosahexaenoic Acids, With Aortic Stiffness in Koreans, Whites, and Japanese Americans

PubMed Central

2013-01-01

BACKGROUND Few previous studies have reported the association of aortic stiffness with marine n-3 fatty acids (Fas) in the general population. The aim of this study was to determine the combined and independent associations of 2 major marine n-3 FAs, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), with aortic stiffness evaluated using carotid–femoral pulse wave velocity (cfPWV) in Korean, white, and Japanese American men. METHODS A population-based sample of 851 middle-aged men (299 Koreans, 266 whites, and 286 Japanese Americans) was examined for cfPWV during 2002–2006. Serum FAs, including EPA and DHA, were measured as a percentage of total FAs using gas chromatography. Multiple regression analysis was used to examine the association of EPA and DHA with cfPWV after adjusting for blood pressure and other confounders. RESULTS Mean EPA and DHA levels were 1.9 (SD = 1.0) and 4.8 (SD = 1.4) for Koreans, 0.8 (SD = 0.6) and 2.4 (SD = 1.2) for whites, and 1.0 (SD = 1.0) and 3.2 (SD = 1.4) for Japanese Americans. Both EPA and DHA were significantly higher in Koreans than in the other 2 groups (P < 0.01). Multiple regression analyses in Koreans showed that cfPWV had a significant inverse association with total marine n-3 FAs and with EPA alone after adjusting for blood pressure and other potential confounders. In contrast, there was no significant association of cfPWV with DHA. Whites and Japanese Americans did not show any significant associations of cfPWV with total marine n-3 FAs, EPA, or DHA. CONCLUSIONS High levels of EPA observed in Koreans have an inverse association with aortic stiffness. PMID:23820020

A human fatty acid synthase inhibitor binds β-ketoacyl reductase in the keto-substrate site.

PubMed

Hardwicke, Mary Ann; Rendina, Alan R; Williams, Shawn P; Moore, Michael L; Wang, Liping; Krueger, Julie A; Plant, Ramona N; Totoritis, Rachel D; Zhang, Guofeng; Briand, Jacques; Burkhart, William A; Brown, Kristin K; Parrish, Cynthia A

2014-09-01

Human fatty acid synthase (hFAS) is a complex, multifunctional enzyme that is solely responsible for the de novo synthesis of long chain fatty acids. hFAS is highly expressed in a number of cancers, with low expression observed in most normal tissues. Although normal tissues tend to obtain fatty acids from the diet, tumor tissues rely on de novo fatty acid synthesis, making hFAS an attractive metabolic target for the treatment of cancer. We describe here the identification of GSK2194069, a potent and specific inhibitor of the β-ketoacyl reductase (KR) activity of hFAS; the characterization of its enzymatic and cellular mechanism of action; and its inhibition of human tumor cell growth. We also present the design of a new protein construct suitable for crystallography, which resulted in what is to our knowledge the first co-crystal structure of the human KR domain and includes a bound inhibitor.

Single-Nucleotide Polymorphisms of FAS and FASL Genes and Risk of Idiopathic Aplastic Anemia.

PubMed

Rehman, Sadia; Saba, Nusrat; Naz, Madiha; Ahmed, Parvez; Munir, Saeeda; Sajjad, Sumaira; Tabassum, Sobia; Naseem, Lubna

2018-04-03

FAS/FASL signaling system plays a vital role in the regulation of apoptosis, envisaged as a death process required for immune surveillance to prevent autoimmunity and tumorigenesis along with several other biological activities. Several single-nucleotide polymorphisms (SNPs) of FAS/FASL system can result in aberrant apoptosis, which can cause different cancers and autoimmune diseases. Aplastic anemia (AA) is an autoimmune dysfunction characterized by peripheral blood pancytopenia associated with hypoplasia of bone marrow. The aim of this study was to screen Pakistani AA patients and controls for two Fas SNPs rs2234767 and rs1800682 and two FASLG SNPs rs763110 and rs5030772. Genotyping of 392 DNA samples was done by Tetra-ARMS polymerase chain reaction. Genotypic frequencies of Fas rs1800682 and FASLG rs5030772 showed significance difference in their distribution in both controls and patients, while Fas rs2234767 and FASLG rs763110 SNPs had no such difference. Carriers of rs1800682 AG+GG had a very odd ratio of 4.63, with 95% confidence interval (CI) of 3.01-7.11, while individuals with FASLG rs5030772 AG+GG were more common in controls than patients with OR 0.53 and 95% CI of 0.34-0.83. Cumulative effects of these SNPs were analyzed, and they showed almost similar trends; however, Fas rs2234767 and FASLG rs763110 genotypes in combination with Fas rs1800682 and FASLG rs5030772 demonstrated significant association. This study provided information that endorsed the involvement of FAS/FASL system SNPs in the pathogenesis of AA; further studies should be designed to understand the exact role of SNPs that can help in early diagnosis and treatment.

Effect of different polyphenol sources on the efficiency of ellagic acid release by Aspergillus niger.

PubMed

Sepúlveda, Leonardo; de la Cruz, Reynaldo; Buenrostro, José Juan; Ascacio-Valdés, Juan Alberto; Aguilera-Carbó, Antonio Francisco; Prado, Arely; Rodríguez-Herrera, Raúl; Aguilar, Cristóbal Noé

2016-01-01

Fungal hydrolysis of ellagitannins produces hexahydroxydiphenic acid, which is considered an intermediate molecule in ellagic acid release. Ellagic acid has important and desirable beneficial health properties. The aim of this work was to identify the effect of different sources of ellagitannins on the efficiency of ellagic acid release by Aspergillus niger. Three strains of A. niger (GH1, PSH and HT4) were assessed for ellagic acid release from different polyphenol sources: cranberry, creosote bush, and pomegranate used as substrate. Polyurethane foam was used as support for solid-state culture in column reactors. Ellagitannase activity was measured for each of the treatments. Ellagic acid was quantified by high performance liquid chromatography. When pomegranate polyphenols were used, a maximum value of ellagic acid (350.21 mg/g) was reached with A. niger HT4 in solid-state culture. The highest amount of ellagitannase (5176.81 U/l) was obtained at 8h of culture when cranberry polyphenols and strain A. niger PSH were used. Results demonstrated the effect of different polyphenol sources and A. niger strains on ellagic acid release. It was observed that the best source for releasing ellagic acid was pomegranate polyphenols and A. niger HT4 strain, which has the ability to degrade these compounds for obtaining a potent bioactive molecule such as ellagic acid. Copyright © 2015 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

Presence of gonadotropin-releasing hormone and its messenger ribonucleic acid in human ovarian epithelial carcinoma.

PubMed

Ohno, T; Imai, A; Furui, T; Takahashi, K; Tamaya, T

1993-09-01

The purpose of this study was to investigate the expression of gonadotropin-releasing hormone messenger ribonucleic acid and the presence of gonadotropin-releasing hormone in human ovarian carcinoma known to have gonadotropin-releasing hormone binding sites and to be affected by gonadotropin-releasing hormone analog. Human ovarian carcinomas surgically removed and human ovarian carcinoma cell lines were examined. Gonadotropin-releasing hormone was determined by a radioimmunoassay and a bioassay. Gonadotropin-releasing hormone messenger ribonucleic acid was determined by reverse transcription polymerase chain reaction using oligonucleotide primers synthesized according to the published human gonadotropin-releasing hormone sequence. Gonadotropin-releasing hormone was shown to be present in extracts of ovarian mucinous cystadenocarcinoma sample (0.8 +/- 0.12 pg/mg of protein) and ovarian adenocarcinoma cell line SK-OV3 (0.92 +/- 0.17 pg/mg of protein) but not in the normal ovary and placenta. Two of two extract samples from individual cases evoked dose-dependent phosphoinositide breakdown in rat granulosa cells similar to that caused by authentic gonadotropin-releasing hormone. Gonadotropin-releasing hormone messenger ribonucleic acid was detected in two of two mucinous cystadenocarcinoma specimens, one of one serous cystadenocarcinoma, and SK-OV3 cells but not in the dysgerminoma, mucinous cystadenoma, and normal ovary and placenta. The demonstration of gonadotropin-releasing hormone and its messenger ribonucleic acid raises the possibility that gonadotropin-releasing hormone may play an autocrine regulatory role in the growth of ovarian carcinoma.

Hydroxy fatty acids in remote marine aerosols as microbial tracers: Long term study on β-hydroxy fatty acids from the remote marine Island, Chichi-Jima

NASA Astrophysics Data System (ADS)

Tyagi, P.

2014-12-01

To better understand the long-range atmospheric transport of microbial aerosols from Southeast Asia to the western North Pacific, marine aerosols were collected at a remote Island, Chichi-Jima on a biweekly basis during 1990-1993. These samples were investigated for the atmospheric abundances of hydroxy fatty acids (OH FAs). β-OH FAs are the major structural components of endotoxins in the outer membrane of Gram-negative bacteria (GNB) whereas w-OH FAs are present in cell walls of higher plants. Thus, we tested the applicability of the β-OH FAs (C10-C18) and ω-OH FAs (C16-C26) to assess the Gram-negative bacteria (GNB) and contribution of terrestrial higher plants, respectively. The average concentrations of β- and ω-OH FAs show pronounced seasonal variability with spring maximum (~301 ng/m-3 and ~ 272 ng/m-3, respectively). The concentrations of total OH FAs increased in winter/spring and decreased in summer/autumn, except for 1992-93. This seasonal trend can be interpreted by the atmospheric transport of microbial soil dust and higher plant metabolites from the Asian continent during winter/spring, when westerly winds dominate over the western North Pacific. The even carbon predominance of β- and ω-OH FAs (80 and 74 % of total) in marine aerosols could be explained by their significant contribution from GNB and terrestrial higher plants. These results have implications towards assessing the bacterial transport in the continental outflows. This study also confirms that β-OH FAs can be used as bacterial tracers in ambient aerosol samples.Keywords: β- and ω-hydroxy fatty acids, terrestrial biomarkers, marine aerosols, GC-MS

The Pla Protease of Yersinia pestis Degrades Fas Ligand to Manipulate Host Cell Death and Inflammation

PubMed Central

Caulfield, Adam J.; Walker, Margaret E.; Gielda, Lindsay M.; Lathem, Wyndham W.

2014-01-01

SUMMARY Pneumonic plague is a deadly respiratory disease caused by Yersinia pestis. The bacterial protease Pla contributes to disease progression and manipulation of host immunity, but the mechanisms by which this occurs are largely unknown. Here we show that Pla degrades the apoptotic signaling molecule Fas ligand (FasL) to prevent host cell apoptosis and inflammation. Wild-type Y. pestis, but not a Pla mutant (Δpla), degrades FasL, which results in decreased downstream caspase-3/7 activation and reduced apoptosis. Similarly, lungs of mice challenged with wild-type Y. pestis show reduced levels of FasL and activated caspase-3/7 compared to Δpla infection. Consistent with a role for FasL in regulating immune responses, Δpla infection results in aberrant pro-inflammatory cytokine levels. The loss of FasL or inhibition of caspase activity alters host inflammatory responses and enables enhanced Y. pestis outgrowth in the lungs. Thus, by degrading FasL, Y. pestis manipulates host cell death pathways to facilitate infection. PMID:24721571

The Potentials of Fas Receptors and Ligands in Monitoring HIV-1 Disease in Children in Yaoundé, Cameroon.

PubMed

Ikomey, G; Assoumou, M-C Okomo; Atashili, J; Mesembe, M; Mukwele, B; Lyonga, E; Eyoh, A; Kafando, A; Ndumbe, P M

2016-09-01

Difficulties in systematically monitoring HIV viral load in resource-limited settings prompt the search for alternate approaches. The authors aimed at assessing the correlation between the plasma levels of soluble forms of Fas receptors (Fas) and Fas ligands (FasL) with standard indicators of HIV disease progression in children. Twenty-two HIV-1-positive children were enrolled in Yaounde. CD4 counts, CD4% counts, plasma levels of Fas, FasL, and HIV-1 RNA levels were assayed. The correlation coefficients (P values) between FasL levels and each of HIV-1 viral load, CD4 counts, and CD4% were, respectively, .56 (.01), -.29 (.18), and .30 (.18). On the other hand, the respective correlation coefficients (P values) with Fas levels were .12 (.60), -.30 (.18), and -.29 (.19). The significant correlation between levels of HIV-1 viral load and FasL suggests that the latter needs to be further studied as a potential biomarker to monitor HIV-1 disease progression in children in resource-limited setting. © The Author(s) 2013.

Prominent dominant negative effect of a mutant Fas molecule lacking death domain on cell-mediated induction of apoptosis.

PubMed

Yokota, Aya; Takeuchi, Emiko; Iizuka, Misao; Ikegami, Yuko; Takayama, Hajime; Shinohara, Nobukata

2005-01-01

Using a panel of transfectant B lymphoma cells expressing varying amounts of the mutant Fas together with the endogenous wild type Fas, semi-quantitative studies on the dominant negative effect of a murine mutant Fas molecule lacking death domain were carried out. In anti-Fas antibody-mediated induction of apoptosis, the mutant molecules exerted significant dominant-negative effect only when their expression level was comparable to or higher than that of wild type molecules, or when exposed to low amounts of the antibody. The inhibitory effect was accompanied by the failure in DISC formation in spite of Fas aggregation. When they were subjected to T cell-mediated Fas-based induction of apoptosis, however, the dominant negative effect was prominent such that the expression of even a small amount of the mutant molecules resulted in significant inhibition. Such a strong inhibitory effect explains the dominant phenotype of this type of mutant Fas molecules in ALPS heterozygous patients and also implies that the physiological effectors for Fas in vivo are cells, i.e., FasL-expressing activated T cells.

Micromotors Spontaneously Neutralize Gastric Acid for pH-Responsive Payload Release.

PubMed

Li, Jinxing; Angsantikul, Pavimol; Liu, Wenjuan; Esteban-Fernández de Ávila, Berta; Thamphiwatana, Soracha; Xu, Mingli; Sandraz, Elodie; Wang, Xiaolei; Delezuk, Jorge; Gao, Weiwei; Zhang, Liangfang; Wang, Joseph

2017-02-13

The highly acidic gastric environment creates a physiological barrier for using therapeutic drugs in the stomach. While proton pump inhibitors have been widely used for blocking acid-producing enzymes, this approach can cause various adverse effects. Reported herein is a new microdevice, consisting of magnesium-based micromotors which can autonomously and temporally neutralize gastric acid through efficient chemical propulsion in the gastric fluid by rapidly depleting the localized protons. Coating these micromotors with a cargo-containing pH-responsive polymer layer leads to autonomous release of the encapsulated payload upon gastric-acid neutralization by the motors. Testing in a mouse model demonstrate that these motors can safely and rapidly neutralize gastric acid and simultaneously release payload without causing noticeable acute toxicity or affecting the stomach function, and the normal stomach pH is restored within 24 h post motor administration. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Production of Medium Chain Fatty Acids by Yarrowia lipolytica: Combining Molecular Design and TALEN to Engineer the Fatty Acid Synthase.

PubMed

Rigouin, Coraline; Gueroult, Marc; Croux, Christian; Dubois, Gwendoline; Borsenberger, Vinciane; Barbe, Sophie; Marty, Alain; Daboussi, Fayza; André, Isabelle; Bordes, Florence

2017-10-20

Yarrowia lipolytica is a promising organism for the production of lipids of biotechnological interest and particularly for biofuel. In this study, we engineered the key enzyme involved in lipid biosynthesis, the giant multifunctional fatty acid synthase (FAS), to shorten chain length of the synthesized fatty acids. Taking as starting point that the ketoacyl synthase (KS) domain of Yarrowia lipolytica FAS is directly involved in chain length specificity, we used molecular modeling to investigate molecular recognition of palmitic acid (C16 fatty acid) by the KS. This enabled to point out the key role of an isoleucine residue, I1220, from the fatty acid binding site, which could be targeted by mutagenesis. To address this challenge, TALEN (transcription activator-like effector nucleases)-based genome editing technology was applied for the first time to Yarrowia lipolytica and proved to be very efficient for inducing targeted genome modifications. Among the generated FAS mutants, those having a bulky aromatic amino acid residue in place of the native isoleucine at position 1220 led to a significant increase of myristic acid (C14) production compared to parental wild-type KS. Particularly, the best performing mutant, I1220W, accumulates C14 at a level of 11.6% total fatty acids. Overall, this work illustrates how a combination of molecular modeling and genome-editing technology can offer novel opportunities to rationally engineer complex systems for synthetic biology.

Controlled release properties of zein-fatty acid blend films for multiple bioactive compounds.

PubMed

Arcan, Iskender; Yemenicioğlu, Ahmet

2014-08-13

To develop edible films having controlled release properties for multiple bioactive compounds, hydrophobicity and morphology of zein films were modified by blending zein with oleic (C18:1)Δ⁹, linoleic (C18:2)Δ(9,12), or lauric (C₁₂) acids in the presence of lecithin. The blend zein films showed 2-8.5- and 1.6-2.9-fold lower initial release rates for the model active compounds, lysozyme (LYS) and (+)-catechin (CAT), than the zein control films, respectively. The change of fatty acid chain length affected both CAT and LYS release rates while the change of fatty acid double bond number affected only the CAT release rate. The film morphologies suggested that the blend films owe their controlled release properties mainly to the microspheres formed within their matrix and encapsulation of active compounds. The blend films showed antilisterial activity and antioxidant activity up to 81 μmol Trolox/cm². The controlled release of multiple bioactive compounds from a single film showed the possibility of combining application of active and bioactive packaging technologies and improving not only safety and quality but also health benefits of packed food.

Enantioselectivity of anteiso-fatty acids in hitherto uninspected sample matrices.

PubMed

Eibler, Dorothee; Seyfried, Carolin; Vetter, Walter

2017-09-01

Anteiso-fatty acids (aFAs) are chiral molecules due to a methyl substituent on the antepenultimate carbon of the otherwise straight acyl chain. 12-Methyltetradecanoic acid (a15:0) and 14-methylhexadecanoic acid (a17:0) are the predominant aFAs in nature but their individual contributions e.g. to food lipids are usually low. Enantioselective data has been collected in fish, bovine milk/cheese, and Brussels sprouts. In this study, we determined the enantioselectivity of a15:0 and a17:0 in shea butter, moose and camel milk, two soil samples and mold (collected from contaminated cheese). For this purpose, sample lipids were extracted and containing fatty acids were converted into methyl esters. Methyl esters of aFAs were selectively enriched by hydrogenation, urea complexation and/or RP-HPLC-fractionation. Enantioselective gas chromatography with mass spectrometry operated in the selected ion monitoring mode using a chiral stationary phase consisting of 66% tert.-butyldimethylsilylated β-cyclodextrin in OV-1701. While a15:0 and a17:0 in moose milk were (S)-enantiopure, all other determined samples contained up to 10% (R)-aFAs. The highest proportions of (R)-enantiomers were detected in the soil samples (ee=80%). Copyright © 2017 Elsevier B.V. All rights reserved.

Effective Teaching for FAS & FAE Children.

ERIC Educational Resources Information Center

Root, Pam

This paper discusses the importance of teaching social skills to children with Fetal Alcohol Syndrome (FAS) or Fetal Alcohol Effect (FAE) and the interrelationship between social skills and academic improvement. Goals and techniques for teaching social skills are identified, including: (1) improving the skill of compliance by setting reasonable…

Gene therapy for human ovarian cancer cells using efficient expression of Fas gene combined with γδT cells.

PubMed

Lin, Jiajing; Zeng, Dingyuan; He, Hongying; Tan, Guangping; Lan, Ying; Jiang, Fuyan; Sheng, Shuting

2017-10-01

Low tissue specificity and efficiency of exogenous gene expression are the two major obstacles in tumor‑targeted gene therapy. The Fas cell surface death receptor (Fas)/Fas ligand pathway is one of the primary pathways responsible for the regulation of cell apoptosis. The aim of the present study was to explore whether the regulation of tumor specific promoters and a two‑step transcriptional amplification system (TSTA) assured efficient, targeted expression of their downstream Fas gene in human ovarian cancer cells, and to assess the killing effect of γδT cells on these cells with high Fas expression. Three shuttle plasmids containing different control elements of the human telomerase reverse transcriptase (hTERT) promoter and/or TSTA were constructed and packaged into adenovirus 5 (Ad5) vectors for the expression of exogenous Fas gene. The human ovarian cancer cell line SKOV3 and a control human embryonic lung fibroblast cell line were transfected with Ad5‑hTERT‑Fas or Ad5‑hTERT‑TSTA‑Fas. Fas mRNA and protein expression were examined by reverse transcription‑quantitative polymerase chain reaction and western blot analysis. γδT lymphocytes were isolated, cultured and mixed at different ratios with SKOV3 cells with Fas expression in order to assess the killing effect of γδT cells. hTERT promoter induced the specific expression of FAS gene in SKOV3 cells, and the TSTA strategy increased FAS expression by 14.2‑fold. The killing effect of γδT cells increased with the expression level of Fas and the effector‑target cell ratio. The killing rate for SKOV3 cells with high FAS expression was 72.5% at an effector‑target cell ratio of 40:1. The regulators of hTERT promoter and TSTA assure the efficient and targeted expression of their downstream Fas gene in SKOV3 cells. The killing effect of γδT cells for ovarian cancer cells with relatively high Fas expression was improved.

Keratin impact on PKCδ- and ASMase-mediated regulation of hepatocyte lipid raft size – implication for FasR-associated apoptosis

PubMed Central

Gilbert, Stéphane; Loranger, Anne; Omary, M. Bishr

2016-01-01

ABSTRACT Keratins are epithelial cell intermediate filament (IF) proteins that are expressed as pairs in a cell-differentiation-regulated manner. Hepatocytes express the keratin 8 and 18 pair (denoted K8/K18) of IFs, and a loss of K8 or K18, as in K8-null mice, leads to degradation of the keratin partner. We have previously reported that a K8/K18 loss in hepatocytes leads to altered cell surface lipid raft distribution and more efficient Fas receptor (FasR, also known as TNFRSF6)-mediated apoptosis. We demonstrate here that the absence of K8 or transgenic expression of the K8 G62C mutant in mouse hepatocytes reduces lipid raft size. Mechanistically, we find that the lipid raft size is dependent on acid sphingomyelinase (ASMase, also known as SMPD1) enzyme activity, which is reduced in absence of K8/K18. Notably, the reduction of ASMase activity appears to be caused by a less efficient redistribution of surface membrane PKCδ toward lysosomes. Moreover, we delineate the lipid raft volume range that is required for an optimal FasR-mediated apoptosis. Hence, K8/K18-dependent PKCδ- and ASMase-mediated modulation of lipid raft size can explain the more prominent FasR-mediated signaling resulting from K8/K18 loss. The fine-tuning of ASMase-mediated regulation of lipid rafts might provide a therapeutic target for death-receptor-related liver diseases. PMID:27422101

Fas Ligand-Mediated Lysis of Self Bystander Targets by Human Papillomavirus-Specific CD8+ Cytotoxic T Lymphocytes

PubMed Central

Smyth, Mark J.; Krasovskis, Erika; Johnstone, Ricky W.

1998-01-01

Mouse cytotoxic T lymphocytes (CTL) reactive with a H-2Db-presented 9-mer peptide of the human papillomavirus type 16 protein E749-57 (RAHYNIVTF) were generated from the spleen cells of wild-type C57BL/6 (B6) or B6 perforin-deficient (B6.P0) mice. CD8+ B6 CTL displayed peptide-specific perforin- and Fas-mediated lysis of E7-transfected mouse RMA lymphoma cells (RMA-E7), while CD8+ CTL from B6.P0 mice lysed RMA-E7 cells via Fas ligand (FasL) exclusively. Rapid and efficient lysis of syngeneic bystander B6 blasts or RMA cells by either B6 or B6.P0 Ag-activated CTL was mediated by a FasL-Fas mechanism. Fas-resistant bystanders were not lysed, nor were allogeneic Fas-sensitive C3H/HeJ (H-2k) or BALB/c (H-2d) bystander blasts. Interestingly, however, phorbol myristate acetate-ionomycin preactivation of B6.P0 effectors enabled lysis of allogeneic H-2k and H-2d bystanders even in the absence of antigenic stimulation. Lysis of syngeneic bystander cells was always FasL-Fas dependent and required effector-bystander contact and, in particular, an interaction between CTL LFA-1 and bystander ICAM-1. Thus, in the context of major histocompatibility complex class I molecule-peptide ligation of the T-cell receptors of CD8+ CTL, neighboring bystander cells that are syngeneic and Fas sensitive and express the adhesion molecule ICAM-1 are potential targets of CTL attack. PMID:9621057

Serum concentrations of fatty acids and colorectal adenoma risk: a case-control study in Japan.

PubMed

Ghadimi, Reza; Kuriki, Kiyonori; Tsuge, Shinji; Takeda, Emiru; Imaeda, Nahomi; Suzuki, Sadao; Sawai, Asuka; Takekuma, Kiyoshi; Hosono, Akihiro; Tokudome, Yuko; Goto, Chiho; Esfandiary, Imaneh; Nomura, Hisashi; Tokudome, Shinkan

2008-01-01

Epidemiologic studies of n-3 fatty acids (FAs) and risk of colorectal cancer have generated inconsistent results, and relations with precursor colorectal adenomas (CRA) have not been evaluated in detail. We here focused on possible associations of serum FAs with CRA in the Japanese population. We conducted a case-control study of 203 asymptomatic CRA cases (148 men, 55 women) and 179 healthy controls (67 men, 112 women) during 1997-2003 in Nagoya, Japan. Baseline information was obtained using a lifestyle questionnaire and serum FA levels were measured by gas chromatography. A non-significant inverse association with CRA was observed for eicosapentaenoic acid (EPA) among women. Moreover, the concentrations of docosahexaenoeic acid (DHA), a major component of n-3 highly-unsaturated FAs (HUFAs), were significantly lower in cases in both sexes. In addition, serum concentrations of total FAs, saturated FAs (SFAs) and mono-unsaturated FAs (MUFAs) had strong positive links with CRA risk. In contrast, arachidonic acid (AA) and DHA were inversely related, with 66% and 59% risk reduction, respectively. Ratios of SFAs/n-3 PUFAs and SFAs/n-3 HUFAs exhibited significant positive relations with CRA risk but there was no clear link with n-6 PUFAs/n-3 PUFAs. Our findings suggest a promoting influence of SFAs and MUFAs along with a protective effect of DHA on CRA risk. However, further research is needed to investigate the observed discrepancy with the generally accepted roles of the AA cascade in carcinogenesis.

Preimplantation maternal stress impairs embryo development by inducing oviductal apoptosis with activation of the Fas system.

PubMed

Zheng, Liang-Liang; Tan, Xiu-Wen; Cui, Xiang-Zhong; Yuan, Hong-Jie; Li, Hong; Jiao, Guang-Zhong; Ji, Chang-Li; Tan, Jing-He

2016-11-01

What are the mechanisms by which the preimplantation restraint stress (PIRS) impairs embryo development and pregnancy outcome? PIRS impairs embryo development by triggering apoptosis in mouse oviducts and embryos,and this involves activation of the Fas system. Although it is known that the early stages of pregnancy are more vulnerable than later stages to prenatalstress, studies on the effect of preimplantation stress on embryo developmentare limited. Furthermore, the mechanisms by which psychological stress impairs embryo development are largely unknown. These issues are worth exploring using the mouse PIRS models because restraint of mice is an efficient experimental procedure developed for studies of psychogenic stress. Mice of Kunming strain, the generalized lymphoproliferative disorder (gld) mice with a germline mutation F273L in FasL in a C57BL/6J genomic background and the wild-type C57BL/6J mice were used. Female and male mice were used 8-10 weeks and 10-12 weeks after birth, respectively. Female mice showing vaginal plugs were paired by weight and randomly assigned to restraint treatments or as controls. For restraint treatment, an individual mouse was put in a micro-cage with food and water available. Control mice remained in their cages with food and water during the time treated females were stressed. Female mice were exposed to PIRS for 48 h starting from 16:00 on the day of vaginal plug detection. At the end of PIRS, levels of glucorticoids (GC), corticotropin-releasing hormone (CRH)and redox potential were measured in serum, while levels of GC, GC receptor (GR), CRH, CRH receptor (CRHR), Fas and Fas ligand (FasL) protein, mRNAs for brain derived neurotrophic factor (BDNF) and insulin-like growth factor-1 (IGF-1), oxidative stress (OS) and apoptosis were examined in oviducts. Preimplantation development and levels of GR, Fas, redox potential and apoptosis were observed in embryos recovered at different times after the initiation of PIRS. The gld mice

Simulating the Fate and Transport of an Acid Mine Drainage Release

EPA Science Inventory

On August 5, 2015, approximately 3 million gallons of acid mine drainage were released from the Gold King Mine into Cement Creek in the San Juan River watershed (CO, NM, UT). The release further mobilized additional metals, which resulted in a large mass of solids and dissolved m...

Fatty acid synthase inhibition activates AMP-activated protein kinase in SKOV3 human ovarian cancer cells.

PubMed

Zhou, Weibo; Han, Wan Fang; Landree, Leslie E; Thupari, Jagan N; Pinn, Michael L; Bililign, Tsion; Kim, Eun Kyoung; Vadlamudi, Aravinda; Medghalchi, Susan M; El Meskini, Rajaa; Ronnett, Gabriele V; Townsend, Craig A; Kuhajda, Francis P

2007-04-01

Fatty acid synthase (FAS), the enzyme responsible for the de novo synthesis of fatty acids, is highly expressed in ovarian cancers and most common human carcinomas. Inhibition of FAS and activation of AMP-activated protein kinase (AMPK) have been shown to be cytotoxic to human cancer cells in vitro and in vivo. In this report, we explore the cytotoxic mechanism of action of FAS inhibition and show that C93, a synthetic FAS inhibitor, increases the AMP/ATP ratio, activating AMPK in SKOV3 human ovarian cancer cells, which leads to cytotoxicity. As a physiologic consequence of AMPK activation, acetyl-CoA carboxylase (ACC), the rate-limiting enzyme of fatty acid synthesis, was phosphorylated and inhibited whereas glucose oxidation was increased. Despite these attempts to conserve energy, the AMP/ATP ratio increased with worsening cellular redox status. Pretreatment of SKOV3 cells with compound C, an AMPK inhibitor, substantially rescued the cells from C93 cytotoxicity, indicating its dependence on AMPK activation. 5-(Tetradecyloxy)-2-furoic acid, an ACC inhibitor, did not activate AMPK despite inhibiting fatty acid synthesis pathway activity and was not significantly cytotoxic to SKOV3 cells. This indicates that substrate accumulation from FAS inhibition triggering AMPK activation, not end-product depletion of fatty acids, is likely responsible for AMPK activation. C93 also exhibited significant antitumor activity and apoptosis against SKOV3 xenografts in athymic mice without significant weight loss or cytotoxicity to proliferating cellular compartments such as bone marrow, gastrointestinal tract, or skin. Thus, pharmacologic FAS inhibition selectively activates AMPK in ovarian cancer cells, inducing cytotoxicity while sparing most normal human tissues from the pleiotropic effects of AMPK activation.

Tissue Inhibitor of Metalloproteinase-3 (TIMP-3) induces FAS dependent apoptosis in human vascular smooth muscle cells.

PubMed

English, William R; Ireland-Zecchini, Heather; Baker, Andrew H; Littlewood, Trevor D; Bennett, Martin R; Murphy, Gillian

2018-01-01

Over expression of Tissue Inhibitor of Metalloproteinases-3 (TIMP-3) in vascular smooth muscle cells (VSMCs) induces apoptosis and reduces neointima formation occurring after saphenous vein interposition grafting or coronary stenting. In studies to address the mechanism of TIMP-3-driven apoptosis in human VSMCs we find that TIMP-3 increased activation of caspase-8 and apoptosis was inhibited by expression of Cytokine response modifier A (CrmA) and dominant negative FAS-Associated protein with Death Domain (FADD). TIMP-3 induced apoptosis did not cause mitochondrial depolarisation, increase activation of caspase-9 and was not inhibited by over-expression of B-cell Lymphoma 2 (Bcl2), indicating a mitochondrial independent/type-I death receptor pathway. TIMP-3 increased levels of the First Apoptosis Signal receptor (FAS) and depletion of FAS with shRNA showed TIMP-3-induced apoptosis was FAS dependent. TIMP-3 induced formation of the Death-Inducing Signalling Complex (DISC), as detected by immunoprecipitation and by immunofluorescence. Cellular-FADD-like IL-1 converting enzyme-Like Inhibitory Protein (c-FLIP) localised with FAS at the cell periphery in the absence of TIMP-3 and this localisation was lost on TIMP-3 expression with c-FLIP adopting a perinuclear localisation. Although TIMP-3 inhibited FAS shedding, this did not increase total surface levels of FAS but instead increased FAS levels within localised regions at the cell surface. A Disintegrin And Metalloproteinase 17 (ADAM17) is inhibited by TIMP-3 and depletion of ADAM17 with shRNA significantly decreased FAS shedding. However ADAM17 depletion did not induce apoptosis or replicate the effects of TIMP-3 by increasing localised clustering of cell surface FAS. ADAM17-depleted cells could activate caspase-3 when expressing levels of TIMP-3 that were otherwise sub-apoptotic, suggesting a partial role for ADAM17 mediated ectodomain shedding in TIMP-3 mediated apoptosis. We conclude that TIMP-3 induced apoptosis

Tissue Inhibitor of Metalloproteinase–3 (TIMP-3) induces FAS dependent apoptosis in human vascular smooth muscle cells

PubMed Central

Ireland-Zecchini, Heather; Baker, Andrew H.; Littlewood, Trevor D.; Bennett, Martin R.; Murphy, Gillian

2018-01-01

Over expression of Tissue Inhibitor of Metalloproteinases-3 (TIMP-3) in vascular smooth muscle cells (VSMCs) induces apoptosis and reduces neointima formation occurring after saphenous vein interposition grafting or coronary stenting. In studies to address the mechanism of TIMP-3-driven apoptosis in human VSMCs we find that TIMP-3 increased activation of caspase-8 and apoptosis was inhibited by expression of Cytokine response modifier A (CrmA) and dominant negative FAS-Associated protein with Death Domain (FADD). TIMP-3 induced apoptosis did not cause mitochondrial depolarisation, increase activation of caspase-9 and was not inhibited by over-expression of B-cell Lymphoma 2 (Bcl2), indicating a mitochondrial independent/type-I death receptor pathway. TIMP-3 increased levels of the First Apoptosis Signal receptor (FAS) and depletion of FAS with shRNA showed TIMP-3-induced apoptosis was FAS dependent. TIMP-3 induced formation of the Death-Inducing Signalling Complex (DISC), as detected by immunoprecipitation and by immunofluorescence. Cellular-FADD-like IL-1 converting enzyme-Like Inhibitory Protein (c-FLIP) localised with FAS at the cell periphery in the absence of TIMP-3 and this localisation was lost on TIMP-3 expression with c-FLIP adopting a perinuclear localisation. Although TIMP-3 inhibited FAS shedding, this did not increase total surface levels of FAS but instead increased FAS levels within localised regions at the cell surface. A Disintegrin And Metalloproteinase 17 (ADAM17) is inhibited by TIMP-3 and depletion of ADAM17 with shRNA significantly decreased FAS shedding. However ADAM17 depletion did not induce apoptosis or replicate the effects of TIMP-3 by increasing localised clustering of cell surface FAS. ADAM17-depleted cells could activate caspase-3 when expressing levels of TIMP-3 that were otherwise sub-apoptotic, suggesting a partial role for ADAM17 mediated ectodomain shedding in TIMP-3 mediated apoptosis. We conclude that TIMP-3 induced apoptosis

FAS/FASL are dysregulated in chordoma and their loss-of-function impairs zebrafish notochord formation

PubMed Central

Libera, Laura; Boari, Nicola; Mortini, Pietro; Bellipanni, Gianfranco; Giordano, Antonio; Cotelli, Franco; Riva, Paola

2014-01-01

Chordoma is a rare malignant tumor that recapitulates the notochord phenotype and is thought to derive from notochord remnants not correctly regressed during development. Apoptosis is necessary for the proper notochord development in vertebrates, and the apoptotic pathway mediated by Fas and Fasl has been demonstrated to be involved in notochord cells regression. This study was conducted to investigate the expression of FAS/FASL pathway in a cohort of skull base chordomas and to analyze the role of fas/fasl homologs in zebrafish notochord formation. FAS/FASL expression was found to be dysregulated in chordoma leading to inactivation of the downstream Caspases in the samples analyzed. Both fas and fasl were specifically expressed in zebrafish notochord sorted cells. fas and fasl loss-of-function mainly resulted in larvae with notochord multi-cell-layer jumps organization, larger vacuolated notochord cells, defects in the peri-notochordal sheath structure and in vertebral mineralization. Interestingly, we observed the persistent expression of ntla and col2a1a, the zebrafish homologs of the human T gene and COL2A1 respectively, which are specifically up-regulated in chordoma. These results demonstrate for the first time the dysregulation of FAS/FASL in chordoma and their role in notochord formation in the zebrafish model, suggesting their possible implication in chordoma onset. PMID:25071022

FAS/FASL are dysregulated in chordoma and their loss-of-function impairs zebrafish notochord formation.

PubMed

Ferrari, Luca; Pistocchi, Anna; Libera, Laura; Boari, Nicola; Mortini, Pietro; Bellipanni, Gianfranco; Giordano, Antonio; Cotelli, Franco; Riva, Paola

2014-07-30

Chordoma is a rare malignant tumor that recapitulates the notochord phenotype and is thought to derive from notochord remnants not correctly regressed during development. Apoptosis is necessary for the proper notochord development in vertebrates, and the apoptotic pathway mediated by Fas and Fasl has been demonstrated to be involved in notochord cells regression. This study was conducted to investigate the expression of FAS/FASL pathway in a cohort of skull base chordomas and to analyze the role of fas/fasl homologs in zebrafish notochord formation. FAS/FASL expression was found to be dysregulated in chordoma leading to inactivation of the downstream Caspases in the samples analyzed. Both fas and fasl were specifically expressed in zebrafish notochord sorted cells. fas and fasl loss-of-function mainly resulted in larvae with notochord multi-cell-layer jumps organization, larger vacuolated notochord cells, defects in the peri-notochordal sheath structure and in vertebral mineralization. Interestingly, we observed the persistent expression of ntla and col2a1a, the zebrafish homologs of the human T gene and COL2A1 respectively, which are specifically up-regulated in chordoma. These results demonstrate for the first time the dysregulation of FAS/FASL in chordoma and their role in notochord formation in the zebrafish model, suggesting their possible implication in chordoma onset.

Keratin impact on PKCδ- and ASMase-mediated regulation of hepatocyte lipid raft size - implication for FasR-associated apoptosis.

PubMed

Gilbert, Stéphane; Loranger, Anne; Omary, M Bishr; Marceau, Normand

2016-09-01

Keratins are epithelial cell intermediate filament (IF) proteins that are expressed as pairs in a cell-differentiation-regulated manner. Hepatocytes express the keratin 8 and 18 pair (denoted K8/K18) of IFs, and a loss of K8 or K18, as in K8-null mice, leads to degradation of the keratin partner. We have previously reported that a K8/K18 loss in hepatocytes leads to altered cell surface lipid raft distribution and more efficient Fas receptor (FasR, also known as TNFRSF6)-mediated apoptosis. We demonstrate here that the absence of K8 or transgenic expression of the K8 G62C mutant in mouse hepatocytes reduces lipid raft size. Mechanistically, we find that the lipid raft size is dependent on acid sphingomyelinase (ASMase, also known as SMPD1) enzyme activity, which is reduced in absence of K8/K18. Notably, the reduction of ASMase activity appears to be caused by a less efficient redistribution of surface membrane PKCδ toward lysosomes. Moreover, we delineate the lipid raft volume range that is required for an optimal FasR-mediated apoptosis. Hence, K8/K18-dependent PKCδ- and ASMase-mediated modulation of lipid raft size can explain the more prominent FasR-mediated signaling resulting from K8/K18 loss. The fine-tuning of ASMase-mediated regulation of lipid rafts might provide a therapeutic target for death-receptor-related liver diseases. © 2016. Published by The Company of Biologists Ltd.

TRIGLYCERIDES, ATHEROSCLEROSIS, AND CARDIOVASCULAR OUTCOME STUDIES: FOCUS ON OMEGA-3 FATTY ACIDS.

PubMed

Handelsman, Yehuda; Shapiro, Michael D

2017-01-01

To provide an overview of the roles of triglycerides and triglyceride-lowering agents in atherosclerosis in the context of cardiovascular outcomes studies. We reviewed the published literature as well as ClinicalTrials.gov entries for ongoing studies. Despite improved atherosclerotic cardiovascular disease (ASCVD) outcomes with statin therapy, residual risk remains. Epidemiologic data and recent genetic insights provide compelling evidence that triglycerides are in the causal pathway for the development of atherosclerosis, thereby renewing interest in targeting triglycerides to improve ASCVD outcomes. Fibrates, niacin, and omega-3 fatty acids (OM3FAs) are three classes of triglyceride-lowering drugs. Outcome studies with triglyceride-lowering agents have been inconsistent. With regard to OM3FAs, the JELIS study showed that eicosapentaenoic acid (EPA) significantly reduced major coronary events in statin-treated hypercholesterolemic patients. Regarding other agents, extended-release niacin and fenofibrate are no longer recommended as statin add-on therapy (by some guidelines, though not all) because of the lack of convincing evidence from outcome studies. Notably, subgroup analyses from the outcome studies have generated the hypothesis that triglyceride lowering may provide benefit in statin-treated patients with persistent hypertriglyceridemia. Two ongoing OM3FA outcome studies (REDUCE-IT and STRENGTH) are testing this hypothesis in high-risk, statin-treated patients with triglyceride levels of 200 to 500 mg/dL. There is consistent evidence that triglycerides are in the causal pathway of atherosclerosis but inconsistent evidence from cardiovascular outcomes studies as to whether triglyceride-lowering agents reduce cardiovascular risk. Ongoing outcomes studies will determine the role of triglyceride lowering in statin-treated patients with high-dose prescription OM3FAs in terms of improved ASCVD outcomes. AACE = American Association of Clinical Endocrinologists

An Evolution-Guided Analysis Reveals a Multi-Signaling Regulation of Fas by Tyrosine Phosphorylation and its Implication in Human Cancers

PubMed Central

Chakrabandhu, Krittalak; Huault, Sébastien; Durivault, Jérôme; Lang, Kévin; Ta Ngoc, Ly; Bole, Angelique; Doma, Eszter; Dérijard, Benoit; Gérard, Jean-Pierre; Pierres, Michel; Hueber, Anne-Odile

2016-01-01

Demonstrations of both pro-apoptotic and pro-survival abilities of Fas (TNFRSF6/CD95/APO-1) have led to a shift from the exclusive “Fas apoptosis” to “Fas multisignals” paradigm and the acceptance that Fas-related therapies face a major challenge, as it remains unclear what determines the mode of Fas signaling. Through protein evolution analysis, which reveals unconventional substitutions of Fas tyrosine during divergent evolution, evolution-guided tyrosine-phosphorylated Fas proxy, and site-specific phosphorylation detection, we show that the Fas signaling outcome is determined by the tyrosine phosphorylation status of its death domain. The phosphorylation dominantly turns off the Fas-mediated apoptotic signal, while turning on the pro-survival signal. We show that while phosphorylations at Y232 and Y291 share some common functions, their contributions to Fas signaling differ at several levels. The findings that Fas tyrosine phosphorylation is regulated by Src family kinases (SFKs) and the phosphatase SHP-1 and that Y291 phosphorylation primes clathrin-dependent Fas endocytosis, which contributes to Fas pro-survival signaling, reveals for the first time the mechanistic link between SFK/SHP-1-dependent Fas tyrosine phosphorylation, internalization route, and signaling choice. We also demonstrate that levels of phosphorylated Y232 and Y291 differ among human cancer types and differentially respond to anticancer therapy, suggesting context-dependent involvement of Fas phosphorylation in cancer. This report provides a new insight into the control of TNF receptor multisignaling by receptor phosphorylation and its implication in cancer biology, which brings us a step closer to overcoming the challenge in handling Fas signaling in treatments of cancer as well as other pathologies such as autoimmune and degenerative diseases. PMID:26942442

Active food packaging based on molecularly imprinted polymers: study of the release kinetics of ferulic acid.

PubMed

Otero-Pazos, Pablo; Rodríguez-Bernaldo de Quirós, Ana; Sendón, Raquel; Benito-Peña, Elena; González-Vallejo, Victoria; Moreno-Bondi, M Cruz; Angulo, Immaculada; Paseiro-Losada, Perfecto

2014-11-19

A novel active packaging based on molecularly imprinted polymer (MIP) was developed for the controlled release of ferulic acid. The release kinetics of ferulic acid from the active system to food simulants (10, 20, and 50% ethanol (v/v), 3% acetic acid (w/v), and vegetable oil), substitutes (95% ethanol (v/v) and isooctane), and real food samples at different temperatures were studied. The key parameters of the diffusion process were calculated by using a mathematical modeling based on Fick's second law. The ferulic acid release was affected by the temperature as well as the percentage of ethanol of the simulant. The fastest release occurred in 95% ethanol (v/v) at 20 °C. The diffusion coefficients (D) obtained ranged between 1.8 × 10(-11) and 4.2 × 10(-9) cm(2)/s. A very good correlation between experimental and estimated data was obtained, and consequently the model could be used to predict the release of ferulic acid into food simulants and real food samples.

Controlled release of tyrosol and ferulic acid encapsulated in chitosan-gelatin films after electron beam irradiation

NASA Astrophysics Data System (ADS)

Benbettaïeb, Nasreddine; Assifaoui, Ali; Karbowiak, Thomas; Debeaufort, Frédéric; Chambin, Odile

2016-01-01

This work deals with the study of the release kinetics of antioxidants (ferulic acid and tyrosol) incorporated into chitosan-gelatin edible films after irradiation processes. The aim was to determine the influence of electron beam irradiation (at 60 kGy) on the retention of antioxidants in the film, their release in water (pH=7) at 25 °C, in relation with the barrier and mechanical properties of biopolymer films. The film preparation process coupled to the irradiation induced a loss of about 20% of tyrosol but did not affect the ferulic acid content. However, 27% of the ferulic acid remained entrapped in the biopolymer network during the release experiments whereas all tyrosol was released. Irradiation induced a reduction of the release rate for both compounds, revealing that cross-linking occurred during irradiation. This was confirmed by the mechanical properties enhancement which tensile strength value significantly increased and by the reduction of permeabilities. Although molecular weights, molar volume and molecular radius of the two compounds are very similar, the effective diffusivity of tyrosol was 40 times greater than that of ferulic acid. The much lower effective diffusion coefficient of ferulic acid as determined from the release kinetics was explained by the interactions settled between ferulic acid molecules and the gelatin-chitosan matrix. As expected, the electron beam irradiation allowed modulating the retention and then the release of antioxidants encapsulated.

Complete loss of Fas ligand gene causes massive lymphoproliferation and early death, indicating a residual activity of gld allele.

PubMed

Karray, Saoussen; Kress, Chantal; Cuvellier, Sylvain; Hue-Beauvais, Catherine; Damotte, Diane; Babinet, Charles; Lévi-Strauss, Matthieu

2004-02-15

To investigate the in vivo function of Fas ligand (FasL), we produced a mouse strain with a FasL gene flanked by loxP sequences. Mice with homozygous floxed FasL gene showed no obvious abnormalities. However, germline deletion of the FasL gene, obtained after mating with mice expressing ubiquitous Cre recombinase, resulted in an unexpectedly severe phenotype. FasL(-/-) mice exhibited an extreme splenomegaly and lymphadenopathy associated with lymphocytic infiltration into multiple organs and autoimmune disease. This severe phenotype led to the premature death at 4 mo of age of >50% of the homozygous mice. It stands in sharp contrast with the milder disease observed in gld (generalized lymphoproliferative disease) mice, indicating that the FasL allele of these mice encodes a protein still able to bind, albeit at a very low level, the Fas receptor.

Expression of Fas, FasL, caspase-8 and other factors of the extrinsic apoptotic pathway during the onset of interdigital tissue elimination.

PubMed

Svandova, E Budisova; Vesela, B; Lesot, H; Poliard, A; Matalova, E

2017-04-01

Elimination of the interdigital web is considered to be the classical model for assessing apoptosis. So far, most of the molecules described in the process have been connected to the intrinsic (mitochondrial) pathway. The extrinsic (receptor mediated) apoptotic pathway has been rather neglected, although it is important in development, immunomodulation and cancer therapy. This work aimed to investigate factors of the extrinsic apoptotic machinery during interdigital regression with a focus on three crucial initiators: Fas, Fas ligand and caspase-8. Immunofluorescent analysis of mouse forelimb histological sections revealed abundant expression of these molecules prior to digit separation. Subsequent PCR Array analyses indicated the expression of several markers engaged in the extrinsic pathway. Between embryonic days 11 and 13, statistically significant increases in the expression of Fas and caspase-8 were observed, along with other molecules involved in the extrinsic apoptotic pathway such as Dapk1, Traf3, Tnsf12, Tnfrsf1A and Ripk1. These results demonstrate for the first time the presence of extrinsic apoptotic components in mouse limb development and indicate novel candidates in the molecular network accompanying the regression of interdigital tissue during digitalisation.

Saturated fatty acid determination method using paired ion electrospray ionization mass spectrometry coupled with capillary electrophoresis.

PubMed

Lee, Ji-Hyun; Kim, Su-Jin; Lee, Sul; Rhee, Jin-Kyu; Lee, Soo Young; Na, Yun-Cheol

2017-09-01

A sensitive and selective capillary electrophoresis-mass spectrometry (CE-MS) method for determination of saturated fatty acids (FAs) was developed by using dicationic ion-pairing reagents forming singly charged complexes with anionic FAs. For negative ESI detection, 21 anionic FAs at pH 10 were separated using ammonium formate buffer containing 40% acetonitrile modifier in normal polarity mode in CE by optimizing various parameters. This method showed good separation efficiency, but the sensitivity of the method to short-chain fatty acids was quite low, causing acetic and propionic acids to be undetectable even at 100 mgL -1 in negative ESI-MS detection. Out of the four dicationic ion-pairing reagents tested, N,N'-dibutyl 1,1'-pentylenedipyrrolidium infused through a sheath-liquid ion source during CE separation was the best reagent regarding improved sensitivity and favorably complexed with anionic FAs for detection in positive ion ESI-MS. The monovalent complex showed improved ionization efficiency, providing the limits of detection (LODs) for 15 FAs ranging from 0.13 to 2.88 μg/mL and good linearity (R 2  > 0.99) up to 150 μg/mL. Compared to the negative detection results, the effect was remarkable for the detection of short- and medium-chain fatty acids. The optimized CE-paired ion electrospray (PIESI)-MS method was utilized for the determination of FAs in cheese and coffee with simple pretreatment. This method may be extended for sensitive analysis of unsaturated fatty acids. Copyright © 2017 Elsevier B.V. All rights reserved.

Ocean acidification increases fatty acids levels of larval fish.

PubMed

Díaz-Gil, Carlos; Catalán, Ignacio A; Palmer, Miquel; Faulk, Cynthia K; Fuiman, Lee A

2015-07-01

Rising levels of anthropogenic carbon dioxide in the atmosphere are acidifying the oceans and producing diverse and important effects on marine ecosystems, including the production of fatty acids (FAs) by primary producers and their transfer through food webs. FAs, particularly essential FAs, are necessary for normal structure and function in animals and influence composition and trophic structure of marine food webs. To test the effect of ocean acidification (OA) on the FA composition of fish, we conducted a replicated experiment in which larvae of the marine fish red drum (Sciaenops ocellatus) were reared under a climate change scenario of elevated CO2 levels (2100 µatm) and under current control levels (400 µatm). We found significantly higher whole-body levels of FAs, including nine of the 11 essential FAs, and altered relative proportions of FAs in the larvae reared under higher levels of CO2. Consequences of this effect of OA could include alterations in performance and survival of fish larvae and transfer of FAs through food webs. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Enhancement of nitric oxide release and hemocompatibility by surface chirality of D-tartaric acid grafting

NASA Astrophysics Data System (ADS)

Han, Honghong; Wang, Ke; Fan, Yonghong; Pan, Xiaxin; Huang, Nan; Weng, Yajun

2017-12-01

Nitric Oxide (NO) generation from endogenous NO-donors catalyzed by diselenide modified biomaterials has been reported. Here we reported surface chirality by L-tartaric acid and D-tartaric acid grafting on the outermost showed a significant impact on diselenide modified biomaterials, which modulated protein adsorption, NO release and anti-platelet adhesion properties. D-tartaric acid grafted surface showed more blood protein adsorption than that of L-surfaces by QCM analysis, however, ELISA analysis disclosed less fibrinogen denatured on the D surfaces. Due to the surface ratio of selenium decreasing, NO release catalyzed by L-tartaric acid grafting on the outermost significantly decreased in comparison to that of only selenocystamine immobilized surfaces. While NO release catalyzed by D-tartaric acid grafting on the outermost didn't decrease and was similar with that of selenocystamine immobilized surfaces. Surface chirality combined with NO release had synergetic effects on platelet adhesion, and it showed the lowest number of platelets adhered on the D-tartaric acid grafted surfaces. Thus surface chirality from D-tartaric acid grafting enhanced hemocompatibility of the surface in this study. Our work provides new insights into engineering novel blood contacting biomaterials by taking into account surface chirality.

Fatty acids, mercury, and methylmercury bioaccessibility in salmon (Salmo salar) using an in vitro model: Effect of culinary treatment.

PubMed

Costa, Sara; Afonso, Cláudia; Cardoso, Carlos; Batista, Irineu; Chaveiro, Nádia; Nunes, Maria Leonor; Bandarra, Narcisa Maria

2015-10-15

The effect of culinary treatments on the fatty acid profile, mercury (Hg), and methylmercury (MeHg) levels of salmon was studied. The bioaccessibility of fatty acids, Hg, and MeHg in raw and grilled salmon was determined. The most intense thermal treatment (grilling) did not alter the relative fatty acid (FA) profile. There were bioaccessibility differences between FAs. To the authors' knowledge, for the first time, higher bioaccessibility of the long-chain FAs than the short- and medium-chain FAs was measured. Chemical interaction phenomena seemed to play a role. On the other hand, higher levels of unsaturation decreased bioaccessibility. Two main alternative hypotheses were put forward, either lower polarity led to higher incorporation of FAs with longer hydrophobic aliphatic chain and lower number of double bonds in the emulsion present in the bioaccessible fraction or enzymatic selectivity preferentially hydrolyzed some FAs on the basis of their structure or position in the triacylglycerol molecule. Copyright © 2015 Elsevier Ltd. All rights reserved.

Serological levels of apoptotic bodies, sFAS and TNF in lupus erythematosus.

PubMed

Alecu, M; Coman, G; Alecu, S

In our study we have investigated the presence of apoptotic bodies, soluble FAS receptor and TNF (tumor necrosis factor) in three clinical forms of lupus erythematosus. Determinations were performed in attack period of: systemic lupus erythematosus (SLE) for 20 patients, 20 patients with subacute cutaneous lupus erythematosus (SCLE), 20 patients with chronic discoid lupus erythematosus (DLE). Determinations were performed by ELISA (for apoptotic bodies, kit Boehringer, normal values 400-800 mU), (for sFAS, kit R&D Systems, normal values 4500-17000 pg/ml) (for TNF, ELISA kit R&D Systems, normal values 0.4-3.6 pg/ml). Results in SLE: apoptotic bodies were increased in 16 cases (980-1030); sFAS in 18 cases (17000-24000 pg/ml) TNF was increased in all 20 cases (40-140 pg/ml). In SCLE with multiple cutaneous lesions and without internal organs disturbance the apoptotic bodies were increased in 10 cases (960-1030 pg/ml), sFAS in 9 cases (17000-22000 pg/ml), and TNF alpha in 9 cases. In DLE, apoptotic bodies were increased in 2 patients (980-1010 pg/ml), sFAS in 3 patients (17000-20000 pg/ml) and TNF in 2 patients (20-40 pg/mil). Investigated values were slightly correlated with immune parameters (anti dsDNA antibodies), but they were correlated with the presence of renal disturbances or extension of cutaneous lesions. We consider that the presence of increased apoptotic bodies as a result of peripheral mononuclear cells apoptosis appear as a nauto-limiting mechanism in a pathological immune response. The increase of sFAS in lupus patients serum might be interpreted as an alteration of apoptosis respectively a deficit in apoptosis which has as a first consequence the persistence of B and T lymphocytes, activated, in the pathogen immune response.

Fatty acid synthase inhibitors from plants: isolation, structure elucidation, and SAR studies.

PubMed

Li, Xing-Cong; Joshi, Alpana S; ElSohly, Hala N; Khan, Shabana I; Jacob, Melissa R; Zhang, Zhizheng; Khan, Ikhlas A; Ferreira, Daneel; Walker, Larry A; Broedel, Sheldon E; Raulli, Robert E; Cihlar, Ronald L

2002-12-01

Fatty acid synthase (FAS) has been identified as a potential antifungal target. FAS prepared from Saccharomyces cerevisiae was employed for bioactivity-guided fractionation of Chlorophora tinctoria,Paspalum conjugatum, Symphonia globulifera, Buchenavia parviflora, and Miconia pilgeriana. Thirteen compounds (1-13), including three new natural products (1, 4, 12), were isolated and their structures identified by spectroscopic interpretation. They represented five chemotypes, namely, isoflavones, flavones, biflavonoids, hydrolyzable tannin-related derivatives, and triterpenoids. 3'-Formylgenistein (1) and ellagic acid 4-O-alpha-l-rhamnopyranoside (9) were the most potent compounds against FAS, with IC(50) values of 2.3 and 7.5 microg/mL, respectively. Furthermore, 43 (14-56) analogues of the five chemotypes from our natural product repository and commercial sources were tested for their FAS inhibitory activity. Structure-activity relationships for some chemotypes were investigated. All these compounds were further evaluated for antifungal activity against Candida albicans and Cryptococcus neoformans. Although there were several antifungal compounds in the set, correlation between the FAS inhibitory activity and antifungal activity could not be defined.

A novel splice variant of the Fas gene in patients with cutaneous T-cell lymphoma.

PubMed

van Doorn, Remco; Dijkman, Remco; Vermeer, Maarten H; Starink, Theo M; Willemze, Rein; Tensen, Cornelis P

2002-10-01

Defective apoptosis signaling has been implicated in the pathogenesis of primary cutaneous T-cell lymphomas (CTCLs), a group of malignancies derived from skin-homing T cells. An important mediator of apoptosis in T cells is the Fas receptor. We identified a novel splice variant of the Fas gene that displays retention of intron 5 and encodes a dysfunctional Fas protein in 13 of 22 patients (59%) in both early and advanced CTCL. Impairment of Fas-induced apoptosis resulting from aberrant splicing potentially contributes to the development and progression of CTCL by allowing continued clonal expansion of activated T cells and by reducing susceptibility to antitumor immune responses.

Crystal structure of FabZ-ACP complex reveals a dynamic seesaw-like catalytic mechanism of dehydratase in fatty acid biosynthesis.

PubMed

Zhang, Lin; Xiao, Jianfeng; Xu, Jianrong; Fu, Tianran; Cao, Zhiwei; Zhu, Liang; Chen, Hong-Zhuan; Shen, Xu; Jiang, Hualiang; Zhang, Liang

2016-12-01

Fatty acid biosynthesis (FAS) is a vital process in cells. Fatty acids are essential for cell assembly and cellular metabolism. Abnormal FAS directly correlates with cell growth delay and human diseases, such as metabolic syndromes and various cancers. The FAS system utilizes an acyl carrier protein (ACP) as a transporter to stabilize and shuttle the growing fatty acid chain throughout enzymatic modules for stepwise catalysis. Studying the interactions between enzymatic modules and ACP is, therefore, critical for understanding the biological function of the FAS system. However, the information remains unclear due to the high flexibility of ACP and its weak interaction with enzymatic modules. We present here a 2.55 Å crystal structure of type II FAS dehydratase FabZ in complex with holo-ACP, which exhibits a highly symmetrical FabZ hexamer-ACP 3 stoichiometry with each ACP binding to a FabZ dimer subunit. Further structural analysis, together with biophysical and computational results, reveals a novel dynamic seesaw-like ACP binding and catalysis mechanism for the dehydratase module in the FAS system, which is regulated by a critical gatekeeper residue (Tyr100 in FabZ) that manipulates the movements of the β-sheet layer. These findings improve the general understanding of the dehydration process in the FAS system and will potentially facilitate drug and therapeutic design for diseases associated with abnormalities in FAS.

Genetic disruption of oncogenic Kras sensitizes lung cancer cells to Fas receptor-mediated apoptosis.

PubMed

Mou, Haiwei; Moore, Jill; Malonia, Sunil K; Li, Yingxiang; Ozata, Deniz M; Hough, Soren; Song, Chun-Qing; Smith, Jordan L; Fischer, Andrew; Weng, Zhiping; Green, Michael R; Xue, Wen

2017-04-04

Genetic lesions that activate KRAS account for ∼30% of the 1.6 million annual cases of lung cancer. Despite clinical need, KRAS is still undruggable using traditional small-molecule drugs/inhibitors. When oncogenic Kras is suppressed by RNA interference, tumors initially regress but eventually recur and proliferate despite suppression of Kras Here, we show that tumor cells can survive knockout of oncogenic Kras , indicating the existence of Kras -independent survival pathways. Thus, even if clinical KRAS inhibitors were available, resistance would remain an obstacle to treatment. Kras -independent cancer cells exhibit decreased colony formation in vitro but retain the ability to form tumors in mice. Comparing the transcriptomes of oncogenic Kras cells and Kras knockout cells, we identified 603 genes that were specifically up-regulated in Kras knockout cells, including the Fas gene, which encodes a cell surface death receptor involved in physiological regulation of apoptosis. Antibodies recognizing Fas receptor efficiently induced apoptosis of Kras knockout cells but not oncogenic Kras -expressing cells. Increased Fas expression in Kras knockout cells was attributed to decreased association of repressive epigenetic marks at the Fas promoter. Concordant with this observation, treating oncogenic Kras cells with histone deacetylase inhibitor and Fas-activating antibody efficiently induced apoptosis, thus bypassing the need to inhibit Kras. Our results suggest that activation of Fas could be exploited as an Achilles' heel in tumors initiated by oncogenic Kras.

Differential Cationization of Fatty Acids with Monovalent Cations Studied by ESI-MS/MS and Computational Approach.

PubMed

Sudarshana Reddy, B; Pavankumar, P; Sridhar, L; Saha, Soumen; Narahari Sastry, G; Prabhakar, S

2018-04-24

The intercellular and intracellular transport of charged species (Na + /K + ) entail interaction of the ions with neutral organic molecules and formation of adduct ions. The rate of transport of the ions across the cell membrane(s) may depend on the stability of the adduct ions, which in turn rely on structural aspects of the organic molecules that interact with the ions. Positive ion ESI mass spectra were recorded for the solutions containing fatty acids (FAs) and monovalent cations (X=Li + , Na + , K + , Rb + and Cs + ). Product ion spectra of the [FA+X] + ions were recorded at different collision energies. Theoretical studies were exploited under both gas phase and solvent phase to investigate the structural effects of the fatty acids during cationization. Stability of [FA+X] + adduct ions were further estimated by means of AIM topological analyses and interaction energy (IE) values. Positive ion ESI-MS analyses of the solution of FAs and X + ions showed preferential binding of the K + ions to FAs. The K + ion binding increased with the increase in number of double bonds of FAs, while decreased with increase in the number of carbons of FAs. Dissociation curves of [FA+X] + ions indicated the relative stability order of the [FA+X] + ions and it was in line with the observed trends in ESI-MS. The solvent phase computational studies divulged the mode of binding and the binding efficiencies of different FAs with monovalent cations. Among the studied monovalent cations, the cationization of FAs follow the order K + >Na + >Li + >Rb + >Cs + . The docosahexaenoic acid showed high efficiency in binding with K + ion. The K + ion binding efficiency of FAs depends on the number of double bonds in unsaturated FAs and the carbon chain length in saturated FAs. The cationization trends of FAs obtained from the ESI-MS, ESI-MS/MS analyses were in good agreement with solvent phase computational studies. This article is protected by copyright. All rights reserved.

Comparison of lipases for in vitro models of gastric digestion: lipolysis using two infant formulas as model substrates.

PubMed

Sassene, P J; Fanø, M; Mu, H; Rades, T; Aquistapace, S; Schmitt, B; Cruz-Hernandez, C; Wooster, T J; Müllertz, A

2016-09-14

The aim of this study was to find a lipase suitable as a surrogate for Human Gastric Lipase (HGL), since the development of predictive gastrointestinal lipolysis models are hampered by the lack of a lipase with similar digestive properties as HGL. Three potential surrogates for HGL; Rhizopus Oryzae Lipase (ROL), Rabbit Gastric Lipase (RGL) and recombinant HGL (rHGL), were used to catalyze the in vitro digestion of two infant formulas (a medium-chain triacylglyceride enriched formula (MC-IF) and a predominantly long-chain triacylglyceride formula (LC-IF)). Digesta were withdrawn after 0, 5, 15, 30, 60 min of gastric digestion and after 90 or 180 min of intestinal digestion with or without the presence of pancreatic enzymes, respectively. The digesta were analyzed by scanning electron microscopy and gas chromatography to quantify the release of fatty acids (FAs). Digestions of both formulas, catalyzed by ROL, showed that the extent of gastric digestion was higher than expected from previously published in vivo data. ROL was furthermore insensitive to FA chain length and all FAs were released at the same pace. RGL and rHGL favoured the release of MC-FAs in both formulas, but rHGL did also release some LC-FAs during digestion of MC-IF, whereas RGL only released MC-FAs. Digestion of a MC-IF by HGL in vivo showed that MC-FAs are preferentially released, but some LC-FAs are also released. Thus of the tested lipase rHGL replicated the digestive properties of HGL the best and is a suitable surrogate for HGL for use in in vitro gastrointestinal lipolysis models.

NF-κB Regulates Caspase-4 Expression and Sensitizes Neuroblastoma Cells to Fas-Induced Apoptosis

PubMed Central

Yang, Hai-Jie; Wang, Mian; Wang, Lei; Cheng, Bin-Feng; Lin, Xiao-Yu; Feng, Zhi-Wei

2015-01-01

Found in neurons and neuroblastoma cells, Fas-induced apoptosis and accompanied activation of NF-κB signaling were thought to be associated with neurodegenerative diseases. However, the detailed functions of NF-κB activation in Fas killing and the effect of NF-κB activation on its downstream events remain unclear. Here, we demonstrated that agonistic Fas antibody induces cell death in a dose-dependent way and NF-κB signaling is activated as well, in neuroblastoma cells SH-EP1. Unexpectedly, NF-κB activation was shown to be pro-apoptotic, as suggested by the reduction of Fas-induced cell death with either a dominant negative form of IκBα (DN-IκBα) or an IκB kinase-specific inhibitor. To our interest, when analyzing downstream events of NF-κB signaling, we found that DN-IκBα only suppressed the expression of caspase-4, but not other caspases. Vice versa, enhancement of NF-κB activity by p65 (RelA) overexpression increased the expression of caspase-4 at both mRNA and protein levels. More directly, results from dual luciferase reporter assay demonstrated the regulation of caspase-4 promoter activity by NF-κB. When caspase-4 activity was blocked by its dominant negative (DN) form, Fas-induced cell death was substantially reduced. Consistently, the cleavage of PARP and caspase-3 induced by Fas was also reduced. In contrast, the cleavage of caspase-8 remained unaffected in caspase-4 DN cells, although caspase-8 inhibitor could rescue Fas-induced cell death. Collectively, these data suggest that caspase-4 activity is required for Fas-induced cell apoptosis and caspase-4 may act upstream of PARP and caspase-3 and downstream of caspase-8. Overall, we demonstrate that NF-κB can mediate Fas-induced apoptosis through caspase-4 protease, indicating that caspase-4 is a new mediator of NF-κB pro-apoptotic pathway in neuroblastoma cells. PMID:25695505

[Effect of total flavones from Cuscuta chinensis on expression of Fas/FasL, PCNA and HB-EGF in SD rats model with bromocriptine-induced abortion].

PubMed

Ma, Hong-Xia; You, Zhao-Ling; Wang, Xiao-Yun

2008-11-01

To explore the effect of total flavones from cuscuta chinensis (TFCC) on expression of Fas, PCNA and HB-EGF in SD rats model with bromocriptine-induced abortion. The model rats of bromocriptine during 6-8 d of pregnancy induced early abortion was established, adopting respectively herbs in high and low dosage and progesterone affect model rat and after 12 d, Immunohistochemical was applied to determine Fas, HB-EGF and PCNA in deciduas and placenta. Expression of PCNA on trophoblast and deciduas, HB-EGF on trophoblast, PR on deciduas in the model used Semen cuscutae flavonoid, proesterone and normal pregnacy, were significantlly higher than those of the pure model. Expression of Fas on trophoblast and deciduas in above four groups, were significantlly lower than those of the pure model. There were no expression of HB-EGF on deciduas. TFCC regulates the proliferation and apoptosis of the deciduas and cytotrophoblasts and prevents spontaneous abortions.

Antimycobacterial action of thiolactomycin: an inhibitor of fatty acid and mycolic acid synthesis.

PubMed Central

Slayden, R A; Lee, R E; Armour, J W; Cooper, A M; Orme, I M; Brennan, P J; Besra, G S

1996-01-01

Thiolactomycin (TLM) possesses in vivo antimycobacterial activity against the saprophytic strain Mycobacterium smegmatis mc2155 and the virulent strain M. tuberculosis Erdman, resulting in complete inhibition of growth on solid media at 75 and 25 micrograms/ml, respectively. Use of an in vitro murine macrophage model also demonstrated the killing of viable intracellular M. tuberculosis in a dose-dependent manner. Through the use of in vivo [1,2-14C]acetate labeling of M. smegmatis, TLM was shown to inhibit the synthesis of both fatty acids and mycolic acids. However, synthesis of the shorter-chain alpha'-mycolates of M. smegmatis was not inhibited by TLM, whereas synthesis of the characteristic longer-chain alpha-mycolates and epoxymycolates was almost completely inhibited at 75 micrograms/ml. The use of M. smegmatis cell extracts demonstrated that TLM specifically inhibited the mycobacterial acyl carrier protein-dependent type II fatty acid synthase (FAS-II) but not the multifunctional type I fatty acid synthase (FAS-I). In addition, selective inhibition of long-chain mycolate synthesis by TLM was demonstrated in a dose-response manner in purified, cell wall-containing extracts of M. smegmatis cells. The in vivo and in vitro data and knowledge of the mechanism of TLM resistance in Escherichia coli suggest that two distinct TLM targets exist in mycobacteria, the beta-ketoacyl-acyl carrier protein synthases involved in FAS-II and the elongation steps leading to the synthesis of the alpha-mycolates and oxygenated mycolates. The efficacy of TLM against M. smegmatis and M. tuberculosis provides the prospects of identifying fatty acid and mycolic acid biosynthetic genes and revealing a novel range of chemotherapeutic agents directed against M. tuberculosis. PMID:9124847

Pin1-FADD interactions regulate Fas-mediated apoptosis in activated eosinophils#

PubMed Central

Oh, Jiyoung; Malter, James S.

2013-01-01

Abnormally long-lived eosinophils (Eos) are the major inflammatory component of allergic responses in the lungs of active asthmatics. Eos recruited to the airways after allergen exposure produce and respond to IL-5 and GM-CSF, enhancing their survival. Pro-survival signaling activates Pin1, a cis-trans peptidyl isomerase (PPIase) that binds to Bax and prevents it activation. How long-lived Eos, despite the continued presence of GM-CSF or IL-5, eventually undergo apoptosis to end allergic inflammation remains unclear. Here we show that Pin1 location, activity and protein interactions are jointly influenced by Fas and pro-survival cytokine IL-5. Fas signaling strongly induced the phosphorylation of FADD at Ser194 and Pin1 at Ser16 as well as their nuclear accumulation. Phospho-mimic Ser194Glu FADD mutants accelerated Eos apoptosis compared to WT or Ser194Ala mutants. Downstream of FADD phosphorylation, Caspase 8, 9 and 3 cleavage as well as Eos apoptosis induced by Fas were reduced by constitutively active Pin1 and enhanced by Pin1 inhibition. Pin1 was activated by IL-5 while simultaneous IL-5 and anti-Fas treatment modestly reduced PPIase activity but induced Pin1 to associate with FADD after its phosphorylation at Ser194. Mechanistically, Pin1 mediated isomerization facilitated the subsequent dephosphorylation of Ser194 FADD and maintenance of cytoplasmic location. In vivo activated bronchoalvelolar (BAL) Eos obtained after allergen challenge showed elevated survival and Pin1 activity that could be reversed by anti-Fas. Therefore, our data suggest that Pin1 is a critical link between FADD mediated cell death and IL-5 mediated pro-survival signaling. PMID:23606538

Interferon-alpha and interferon-gamma modulate Fas-mediated apoptosis in mitomycin-C-resistant human Tenon's fibroblasts.

PubMed

Wang, Xiao Yang; Crowston, Jonathan G; White, Andrew J R; Zoellner, Hans; Healey, Paul R

2014-08-01

The aim of the study was to investigate, using a native mitomycin-C-resistant human Tenon's fibroblast cell line, the possibility that interferon-alpha and gamma could be used with Fas agonists as an alternative anti-fibrotic strategy to mitomycin-C in trabeculectomy. A clinically resistant and in vitro verified mitomycin-C-resistant human Tenon's fibroblast cell line was pretreated with interferon-alpha and interferon-gamma for 48 h before stimulation with an agonistic Fas antibody (CH11) for 2 days to induce cell death. Cell death assays were undertaken. Changes in apoptosis-related proteins were determined by flow cytometry and Western blot. Pretreatment with interferon-alpha or interferon-gamma for 48 h increased Fas, Fas-associated protein with death domain and caspase-8 expression. Protein expression was further increased by combined exposure to interferon-alpha and gamma. Pretreatment with cytokines had no effect on Fas-L and Bcl-2. Interferon-alpha alone did not change the rate of induced cell death. A combination of interferon-alpha and gamma synergistically increased the sensitivity of mitomycin-C-resistant human Tenon's fibroblast cell line to induced cell death. An antagonistic anti-Fas antibody (ZB4) completely blocked induced cell death. Broad caspase inhibitors specific for caspases-8 and -3 reduced induced deaths in interferon pretreated mitomycin-C-resistant human Tenon's fibroblast cell line in a dose-dependent manner. Interferon-alpha and interferon-gamma render mitomycin-C-resistant human Tenon's fibroblast cell line sensitive to Fas-mediated apoptosis. The mechanism involves increased death-inducing signalling complex formation by upregulation of Fas, Fas-associated protein with death domain and caspase-8 expression. © 2013 Royal Australian and New Zealand College of Ophthalmologists.

Development of the SoFAS (solid fats and added sugars) concept: the 2010 Dietary Guidelines for Americans.

PubMed

Nicklas, Theresa A; O'Neil, Carol E

2015-05-01

The diets of most US children and adults are poor, as reflected by low diet quality scores, when compared with the recommendations of the Dietary Guidelines for Americans (DGAs). Contributing to these low scores is that most Americans overconsume solid fats, which may contain saturated fatty acids and added sugars; although alcohol consumption was generally modest, it provided few nutrients. Thus, the 2005 DGAs generated a new recommendation: to reduce intakes of solid fats, alcohol, and added sugars (SoFAAS). What precipitated the emergence of the new SoFAAS terminology was the concept of discretionary calories (a "calorie" is defined as the amount of energy needed to increase the temperature of 1 kg of water by 1°C), which were defined as calories consumed after an individual had met his or her recommended nutrient intakes while consuming fewer calories than the daily recommendation. A limitation with this concept was that additional amounts of nutrient-dense foods consumed beyond the recommended amount were also considered discretionary calories. The rationale for this was that if nutrient-dense foods were consumed beyond recommended amounts, after total energy intake was met then this constituted excess energy intake. In the 2010 DGAs, the terminology was changed to solid fats and added sugars (SoFAS); thus, alcohol was excluded because it made a minor contribution to overall intake and did not apply to children. The SoFAS terminology also negated nutrient-dense foods that were consumed in amounts above the recommendations for the specific food groups in the food patterns. The ambiguous SoFAS terminology was later changed to "empty calories" to reflect only those calories from solid fats and added sugars (and alcohol if consumed beyond moderate amounts). The purpose of this review is to provide an historical perspective on how the dietary recommendations went from SoFAAS to SoFAS and how discretionary calories went to empty calories between the 2005 and 2010

FAP-1-mediated activation of NF-kappaB induces resistance of head and neck cancer to Fas-induced apoptosis.

PubMed

Wieckowski, Eva; Atarashi, Yoshinari; Stanson, Joanna; Sato, Taka-Aki; Whiteside, Theresa L

2007-01-01

Molecular mechanisms responsible for tumor resistance to apoptosis often involve the Fas/FasL pathway. While squamous cell carcinomas of the head and neck (SCCHN) express both Fas and FasL, their resistance to self-induced apoptosis or apoptosis mediated by Fas agonistic antibody (CH-11Ab) was independent of the level of Fas surface expression or the presence of soluble Fas in supernatants of primary or metastatic SCCHN cell lines. By in vitro immunoselection, using PCI-15A cell line treated with successive cycles of CH-11 Ab, Fas-resistant sublines with the parental genotype were selected. Such sublines failed to cleave caspase-8 upon Fas engagement and were resistant to CH-11 Ab, although they remained sensitive to VP-16 or staurosporin. In the presence of cycloheximide, the selected SCCHN sublines become susceptible to CH-11 Ab, and showed cleavage of caspase-8, suggesting that apoptosis resistance was mediated by an inhibitory protein(s) acting upstream of caspase-8. Overexpression of Fas-associated phosphatase 1 (FAP-1), but not cellular FLICE-inhibitory protein (cFLIP) in SCCHN sublines was documented by Western blots and RT-PCR analyses. The FAP-1+ selected sublines also downregulated cell surface Fas. A high phosphorylation level of IkappaB kappa, NFkappaB activation and upregulation of Bcl-2 expression were observed in the FAP-1+ sublines. Treatment with the phosphatase inhibitor, orthovanadate, or silencing of FAP-1 with siRNA abolished their resistance to apoptosis, suggesting that FAP-1 phosphatase activity could be responsible for NF-kappaB activation and resistance of SCCHN cells to Fas-mediated apoptosis. 2006 Wiley-Liss, Inc.

Survival Improvement in Human Retinal Pigment Epithelial Cells via Fas Receptor Targeting by miR-374a.

PubMed

Tasharrofi, Nooshin; Kouhkan, Fatemeh; Soleimani, Masoud; Soheili, Zahra-Sheila; Kabiri, Mahboubeh; Mahmoudi Saber, Mohaddeseh; Dorkoosh, Farid Abedin

2017-12-01

Oxidative conditions of the eye could contribute to retinal cells loss through activating the Fas-L/Fas pathway. This phenomenon is one of the leading causes of some ocular diseases like age-related macular degeneration (AMD). By targeting proteins at their mRNA level, microRNAs (miRNAs) can regulate gene expression and cell function. The aim of the present study is to investigate Fas targeting by miR-374a and find whether it can inhibit Fas-mediated apoptosis in primary human retinal pigment epithelial (RPE) cells under oxidative stress. So, the primary human RPE cells were transfected with pre-miR-374a pLEX construct using polymeric carrier and were exposed to H 2 O 2 (200 μM) as an oxidant agent for induction of Fas expression. Fas expression at mRNA and protein level was evaluated by quantitative real-time PCR and Western blot analysis, respectively. These results revealed that miR-374a could prevent Fas upregulation under oxidative conditions. Moreover, Luciferase activity assay confirmed that Fas could be a direct target of miR-374a. The cell viability studies demonstrated that caspase-3 activity was negligible in miR-374a treated cells compared to the controls. Our data suggest miR-374a is a negative regulator of Fas death receptor which is able to enhance the cell survival and protect RPE cells against oxidative conditions. J. Cell. Biochem. 118: 4854-4861, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

A feedback regulatory loop between G3P and lipid transfer proteins DIR1 and AZI1 mediates azelaic-acid-induced systemic immunity.

PubMed

Yu, Keshun; Soares, Juliana Moreira; Mandal, Mihir Kumar; Wang, Caixia; Chanda, Bidisha; Gifford, Andrew N; Fowler, Joanna S; Navarre, Duroy; Kachroo, Aardra; Kachroo, Pradeep

2013-04-25

Systemic acquired resistance (SAR), a highly desirable form of plant defense, provides broad-spectrum immunity against diverse pathogens. The recent identification of seemingly unrelated chemical inducers of SAR warrants an investigation of their mutual interrelationships. We show that SAR induced by the dicarboxylic acid azelaic acid (AA) requires the phosphorylated sugar derivative glycerol-3-phosphate (G3P). Pathogen inoculation induced the release of free unsaturated fatty acids (FAs) and thereby triggered AA accumulation, because these FAs serve as precursors for AA. AA accumulation in turn increased the levels of G3P, which is required for AA-conferred SAR. The lipid transfer proteins DIR1 and AZI1, both of which are required for G3P- and AA-induced SAR, were essential for G3P accumulation. Conversely, reduced G3P resulted in decreased AZI1 and DIR1 transcription. Our results demonstrate that an intricate feedback regulatory loop among G3P, DIR1, and AZI1 regulates SAR and that AA functions upstream of G3P in this pathway. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

Novel sustained-release dosage forms of proteins using polyglycerol esters of fatty acids.

PubMed

Yamagata, Y; Iga, K; Ogawa, Y

2000-02-03

In order to develop a novel delivery system for proteins based on polyglycerol esters of fatty acids (PGEFs), we studied a model system using interferon-alpha (IFN-alpha) as the test protein. A cylindrical matrix was prepared by a heat extrusion technique using a lyophilized powder of the protein and 11 different types of synthetic PGEFs, which varied in degree of glycerol polymerization (di- and tetra-), chain length of fatty acids (myristate, palmitate and stearate) and degree of fatty acid esterification (mono-, di- and tri-). In an in-vitro release study using an enzyme-linked immunosorbent assay (ELISA) as a detection method, the matrices prepared from a monoglyceride (used for comparison) and from diglycerol esters exhibited a biphasic release pattern with a large initial burst followed by slow release. In contrast, the matrices prepared from tetraglycerol esters showed a steady rate of release without a large initial burst. In an in vivo release study, initial bursts of IFN-alpha release were, also, dramatically reduced when the matrices were prepared from the tetraglycerol esters of palmitate and stearate, and the mean residence time (MRT) of IFN-alpha was prolonged, whereas the matrices prepared from monoglyceride and from diglycerol esters showed large initial bursts of IFN-alpha release. Since the release rates from the matrices prepared from the tetraglycerol esters of palmitate and stearate were governed by Jander's equation modified for a cylindrical matrix, the release from those matrices was concluded to be a diffusion-controlled process. The bioavailability of IFN-alpha after implantation of the matrix formulation prepared using all types of PGEFs, except for tetraglycerol triesters, was almost equivalent to that after injection of IFN-alpha solution; consequently, IFN-alpha in these matrices appears to remain stable during the release period.

[Shikimic acid inhibits the degranulation and histamine release in RBL-2H3 cells].

PubMed

Chen, Xianyong; Zheng, Qianqian; Liu, Wei; Yu, Lingling; Wang, Jinling; Li, Shigang

2017-05-01

Objective To study the effects of shikimic acid on the proliferation of rat RBL-2H3 cells and the degranulation of the cells induced by C48/80 and its mechanism. Methods MTT assay was performed to measure the proliferation of RBL-2H3 cells treated with 3, 10, 30 μg/mL shikimic acid. Toluidine blue staining was used to observe the degranulation of RBL-2H3 cells. The release of β-hexosaminidase from RBL-2H3 cells treated with 0, 12.5, 25, 50, 80, 100 μg/mL C48/80 was determined by substrate assay. ELISA was used to detect the histamine content in the supernatant of each treated group. Results Shikimic acid at 3, 10, 300 μg/mL had no obvious inhibitory effect on the proliferation of RBL-2H3 cells. There was a dose-effect relationship between the degranulation of RBL-2H3 cells and C48/80 concentration. Shikimic acid inhibited the degranulation of RBL-2H3 cells compared with the positive control group, the β-hexosaminidase release rate and histamine release were significantly reduced in RBL-2H3 cells treated with shikimic acid and C48/80. Conclusion Shikimic acid can inhibit the degranulation of RBL-2H3 cells and reduce histamine release.

Fatty acids of erythrocyte membrane in acute pancreatitis patients.

PubMed

Kuliaviene, Irma; Gulbinas, Antanas; Cremers, Johannes; Pundzius, Juozas; Kupcinskas, Limas; Dambrauskas, Zilvinas; Jansen, Eugene

2013-09-14

To evaluate changes in the fatty acid composition of erythrocyte membrane phospholipids during severe and mild acute pancreatitis (AP) of alcoholic and nonalcoholic etiology. All consecutive patients with a diagnosis of AP and onset of the disease within the last 72 h admitted to the Hospital of Lithuanian University of Health Sciences between June and December 2007 were included. According to the Acute Physiology and Chronic Health Evaluation (APACHE II) scale, the patients were subdivided into the mild (APACHE II score < 7, n = 22) and severe (APACHE II score ≥ 7, n = 17) AP groups. Healthy individuals (n = 26) were enrolled as controls. Blood samples were collected from patients on admission to the hospital. Fatty acids (FAs) were extracted from erythrocyte phospholipids and expressed as percentages of the total FAs present in the chromatogram. The concentrations of superoxide dismutase and glutathione peroxidase were measured in erythrocytes. We found an increase in the percentages of saturated and monounsaturated FAs, a decrease in the percentages of total polyunsaturated FAs (PUFAs) and n-3 PUFAs in erythrocyte membrane phospholipids of AP patients compared with healthy controls. Palmitic (C16:0), palmitoleic (C16:1n7cis), arachidonic (C20:4n6), docosahexaenoic (DHA, C22:6n3), and docosapentaenoic (DPA, C22:5n3) acids were the major contributing factors. A decrease in the peroxidation and unsaturation indexes in AP patients as well as the severe and mild AP groups as compared with controls was observed. The concentrations of antioxidant enzymes in the mild AP group were lower than in the control group. In severe AP of nonalcoholic etiology, the percentages of arachidic (C20:0) and arachidonic (C20:4n6) acids were decreased as compared with the control group. The patients with mild AP of nonalcoholic etiology had the increased percentages of total saturated FAs and gama linoleic acid (C18:3n6) and the decreased percentages of elaidic (C18:1n9t

Fatty acids of erythrocyte membrane in acute pancreatitis patients

PubMed Central

Kuliaviene, Irma; Gulbinas, Antanas; Cremers, Johannes; Pundzius, Juozas; Kupcinskas, Limas; Dambrauskas, Zilvinas; Jansen, Eugene

2013-01-01

AIM: To evaluate changes in the fatty acid composition of erythrocyte membrane phospholipids during severe and mild acute pancreatitis (AP) of alcoholic and nonalcoholic etiology. METHODS: All consecutive patients with a diagnosis of AP and onset of the disease within the last 72 h admitted to the Hospital of Lithuanian University of Health Sciences between June and December 2007 were included. According to the Acute Physiology and Chronic Health Evaluation (APACHE II) scale, the patients were subdivided into the mild (APACHE II score < 7, n = 22) and severe (APACHE II score ≥ 7, n = 17) AP groups. Healthy individuals (n = 26) were enrolled as controls. Blood samples were collected from patients on admission to the hospital. Fatty acids (FAs) were extracted from erythrocyte phospholipids and expressed as percentages of the total FAs present in the chromatogram. The concentrations of superoxide dismutase and glutathione peroxidase were measured in erythrocytes. RESULTS: We found an increase in the percentages of saturated and monounsaturated FAs, a decrease in the percentages of total polyunsaturated FAs (PUFAs) and n-3 PUFAs in erythrocyte membrane phospholipids of AP patients compared with healthy controls. Palmitic (C16:0), palmitoleic (C16:1n7cis), arachidonic (C20:4n6), docosahexaenoic (DHA, C22:6n3), and docosapentaenoic (DPA, C22:5n3) acids were the major contributing factors. A decrease in the peroxidation and unsaturation indexes in AP patients as well as the severe and mild AP groups as compared with controls was observed. The concentrations of antioxidant enzymes in the mild AP group were lower than in the control group. In severe AP of nonalcoholic etiology, the percentages of arachidic (C20:0) and arachidonic (C20:4n6) acids were decreased as compared with the control group. The patients with mild AP of nonalcoholic etiology had the increased percentages of total saturated FAs and gama linoleic acid (C18:3n6) and the decreased percentages of elaidic

Expression of fas protein on CD4+T cells irradiated by low level He-Ne

NASA Astrophysics Data System (ADS)

Nie, Fan; Zhu, Jing; Zhang, Hui-Guo

2005-07-01

Objective: To investigate the influence on the Expression of Fas protein on CD4+ T cells irradiated by low level He-Ne laser in the cases of psoriasis. Methods:the expression of CD4+ T Fas protein was determined in the casee of psoriasis(n=5) pre and post-low level laser irradiation(30 min、60min and 120min)by flow cytometry as compared withthe control(n=5). Results:In the cases of psoriasis,the expression of CD4+T FAS protein 21.4+/-3.1% was increased significantly than that of control group 16.8+/-2.1% pre-irradiation, p<0.05in the control,there is no difference between pre and post- irradiation,p>0.05in the cases , the expression of CD4+T Fas protein wae positively corelated to the irradiation times, when the energy density arrived to 22.92J/cm2（60 minutes）and 45.84J/cm2（120minutes）, the expression of CD4+ T Fas protein was increased significantly as compared with pre-irradiation,p<0.05.Conclusion: The expression of CD4+T Fas protein may be increased by low level He-Ne laser irradiation ,the uncontrolled status of apoptosis could be corrected.

Comparison of Two Derivatization Methods for the Analysis of Fatty Acids and Trans Fatty Acids in Bakery Products Using Gas Chromatography

PubMed Central

Salimon, Jumat; Omar, Talal A.; Salih, Nadia

2014-01-01

Two different procedures for the methylation of fatty acids (FAs) and trans fatty acids (TFAs) in food fats were compared using gas chromatography (GC-FID). The base-catalyzed followed by an acid-catalyzed method (KOCH3/HCl) and the base-catalyzed followed by (trimethylsilyl)diazomethane (TMS–DM) method were used to prepare FA methyl esters (FAMEs) from lipids extracted from food products. In general, both methods were suitable for the determination of cis/trans FAs. The correlation coefficients (r) between the methods were relatively small (ranging from 0.86 to 0.99) and had a high level of agreement for the most abundant FAs. The significant differences (P = 0.05) can be observed for unsaturated FAs (UFAs), specifically for TFAs. The results from the KOCH3/HCl method showed the lowest recovery values (%R) and higher variation (from 84% to 112%), especially for UFAs. The TMS-DM method had higher R values, less variation (from 90% to 106%), and more balance between variation and %RSD values in intraday and interday measurements (less than 4% and 6%, resp.) than the KOCH3/HCl method, except for C12:0, C14:0, and C18:0. Nevertheless, the KOCH3/HCl method required shorter time and was less expensive than the TMS-DM method which is more convenient for an accurate and thorough analysis of rich cis/trans UFA samples. PMID:24719581

Comparison of two derivatization methods for the analysis of fatty acids and trans fatty acids in bakery products using gas chromatography.

PubMed

Salimon, Jumat; Omar, Talal A; Salih, Nadia

2014-01-01

Two different procedures for the methylation of fatty acids (FAs) and trans fatty acids (TFAs) in food fats were compared using gas chromatography (GC-FID). The base-catalyzed followed by an acid-catalyzed method (KOCH3/HCl) and the base-catalyzed followed by (trimethylsilyl)diazomethane (TMS-DM) method were used to prepare FA methyl esters (FAMEs) from lipids extracted from food products. In general, both methods were suitable for the determination of cis/trans FAs. The correlation coefficients (r) between the methods were relatively small (ranging from 0.86 to 0.99) and had a high level of agreement for the most abundant FAs. The significant differences (P = 0.05) can be observed for unsaturated FAs (UFAs), specifically for TFAs. The results from the KOCH3/HCl method showed the lowest recovery values (%R) and higher variation (from 84% to 112%), especially for UFAs. The TMS-DM method had higher R values, less variation (from 90% to 106%), and more balance between variation and %RSD values in intraday and interday measurements (less than 4% and 6%, resp.) than the KOCH3/HCl method, except for C12:0, C14:0, and C18:0. Nevertheless, the KOCH3/HCl method required shorter time and was less expensive than the TMS-DM method which is more convenient for an accurate and thorough analysis of rich cis/trans UFA samples.

Diazeniumdiolate-doped poly(lactic-co-glycolic acid)-based nitric oxide releasing films as antibiofilm coatings.

PubMed

Cai, Wenyi; Wu, Jianfeng; Xi, Chuanwu; Meyerhoff, Mark E

2012-11-01

Nitric oxide (NO) releasing films with a bilayer configuration are fabricated by doping dibutyhexyldiamine diazeniumdiolate (DBHD/N2O2) in a poly(lactic-co-glycolic acid) (PLGA) layer and further encapsulating this base layer with a silicone rubber top coating. By incorporating pH sensitive dyes within the films, pH changes in the PLGA layer are visualized and correlated with the NO release profiles (flux vs. time). It is demonstrated that PLGA acts as both a promoter and controller of NO release from the coating by providing protons through its intrinsic acid residues (both end groups and monomeric acid impurities) and hydrolysis products (lactic acid and glycolic acid). Control of the pH changes within the PLGA layer can be achieved by adjusting the ratio of DBHD/N2O2 and utilizing PLGAs with different hydrolysis rates. Coatings with a variety of NO release profiles are prepared with lifetimes of up to 15 d at room temperature (23 °C) and 10 d at 37 °C. When incubated in a CDC flow bioreactor for a one week period at RT or 37 °C, all the NO releasing films exhibit considerable antibiofilm properties against gram-positive Staphylococcus aureus and gram-negative Escherichia coli. In particular, compared to the silicone rubber surface alone, an NO releasing film with a base layer of 30 wt% DBHD/N2O2 mixed with poly(lactic acid) exhibits an ∼98.4% reduction in biofilm biomass of S. aureus and ∼99.9% reduction for E. coli at 37 °C. The new diazeniumdiolate-doped PLGA-based NO releasing coatings are expected to be useful antibiofilm coatings for a variety of indwelling biomedical devices (e.g., catheters). Copyright © 2012 Elsevier Ltd. All rights reserved.

Genetic disruption of oncogenic Kras sensitizes lung cancer cells to Fas receptor-mediated apoptosis

PubMed Central

Mou, Haiwei; Moore, Jill; Malonia, Sunil K.; Li, Yingxiang; Ozata, Deniz M.; Hough, Soren; Song, Chun-Qing; Smith, Jordan L.; Fischer, Andrew; Weng, Zhiping; Xue, Wen

2017-01-01

Genetic lesions that activate KRAS account for ∼30% of the 1.6 million annual cases of lung cancer. Despite clinical need, KRAS is still undruggable using traditional small-molecule drugs/inhibitors. When oncogenic Kras is suppressed by RNA interference, tumors initially regress but eventually recur and proliferate despite suppression of Kras. Here, we show that tumor cells can survive knockout of oncogenic Kras, indicating the existence of Kras-independent survival pathways. Thus, even if clinical KRAS inhibitors were available, resistance would remain an obstacle to treatment. Kras-independent cancer cells exhibit decreased colony formation in vitro but retain the ability to form tumors in mice. Comparing the transcriptomes of oncogenic Kras cells and Kras knockout cells, we identified 603 genes that were specifically up-regulated in Kras knockout cells, including the Fas gene, which encodes a cell surface death receptor involved in physiological regulation of apoptosis. Antibodies recognizing Fas receptor efficiently induced apoptosis of Kras knockout cells but not oncogenic Kras-expressing cells. Increased Fas expression in Kras knockout cells was attributed to decreased association of repressive epigenetic marks at the Fas promoter. Concordant with this observation, treating oncogenic Kras cells with histone deacetylase inhibitor and Fas-activating antibody efficiently induced apoptosis, thus bypassing the need to inhibit Kras. Our results suggest that activation of Fas could be exploited as an Achilles’ heel in tumors initiated by oncogenic Kras. PMID:28320962

Induction of Fas-Mediated Apoptosis by Interferon-γ is Dependent on Granulosa Cell Differentiation and Follicular Maturation in the Rat Ovary.

PubMed

Lee, Hye-Jeong; Kim, Ji Young; Park, Ji Eun; Yoon, Yong-Dal; Tsang, Benjamin K; Kim, Jong-Min

2016-12-01

Fas ligand (FasL) and its receptor Fas have been implicated in granulosa cell apoptosis during follicular atresia. Although interferon-gamma (IFN-γ) is believed to be involved in the regulation Fas expression in differentiated granulosa or granulosa-luteal cells, the expression of this cytokine and its role in the regulation of the granulosa cell Fas/FasL system and apoptosis during follicular maturation have not been thoroughly investigated. In the present study, we have examined the presence of IFN-γ in ovarian follicles at different stage of development by immunohistochemistry and related their relative intensities with follicular expression of Fas and FasL, and with differences in granulosa cell sensitivity to Fas activation by exogenous agonistic Anti-Fas monoclonal antibody (Fas mAb). Although IFN-γ immunostaining was detectable in oocyte and granulosa cells in antral follicles, most intense immunoreactivity for the cytokine was observed in these cells of preantral follicles. Intense immunoreactivity for IFN-γ was most evident in granulosa cells of atretic early antral follicles where increased Fas and FasL expression and apoptosis were also observed. Whereas low concentrations of IFN-γ (10-100 U/mL) significantly increased Fas expression in undifferentiated granulosa cells (from preantral or very early antral follicles) in vitro , very higher concentrations (≥ 1,000 U/mL) were required to up-regulate of Fas in differentiated cells isolated from eCG-primed (antral) follicles. Addition of agonistic Fas mAb to cultures of granulosa cells at the two stages of differentiation and pretreated with IFN-γ (100 U/mL) elicited morphological and biochemical apoptotic features which were more prominent in cells not previously exposed to the gonadotropin in vivo . These findings suggested that IFN-γ is an important physiologic intra-ovarian regulator of follicular atresia and plays a pivotal role in regulation of expression of Fas receptor and subsequent

Induction of Fas-Mediated Apoptosis by Interferon-γ is Dependent on Granulosa Cell Differentiation and Follicular Maturation in the Rat Ovary

PubMed Central

Lee, Hye-Jeong; Kim, Ji Young; Park, Ji Eun; Yoon, Yong-Dal; Tsang, Benjamin K.; Kim, Jong-Min

2016-01-01

ABSTRACT Fas ligand (FasL) and its receptor Fas have been implicated in granulosa cell apoptosis during follicular atresia. Although interferon-gamma (IFN-γ) is believed to be involved in the regulation Fas expression in differentiated granulosa or granulosa-luteal cells, the expression of this cytokine and its role in the regulation of the granulosa cell Fas/FasL system and apoptosis during follicular maturation have not been thoroughly investigated. In the present study, we have examined the presence of IFN-γ in ovarian follicles at different stage of development by immunohistochemistry and related their relative intensities with follicular expression of Fas and FasL, and with differences in granulosa cell sensitivity to Fas activation by exogenous agonistic Anti-Fas monoclonal antibody (Fas mAb). Although IFN-γ immunostaining was detectable in oocyte and granulosa cells in antral follicles, most intense immunoreactivity for the cytokine was observed in these cells of preantral follicles. Intense immunoreactivity for IFN-γ was most evident in granulosa cells of atretic early antral follicles where increased Fas and FasL expression and apoptosis were also observed. Whereas low concentrations of IFN-γ (10-100 U/mL) significantly increased Fas expression in undifferentiated granulosa cells (from preantral or very early antral follicles) in vitro, very higher concentrations (≥ 1,000 U/mL) were required to up-regulate of Fas in differentiated cells isolated from eCG-primed (antral) follicles. Addition of agonistic Fas mAb to cultures of granulosa cells at the two stages of differentiation and pretreated with IFN-γ (100 U/mL) elicited morphological and biochemical apoptotic features which were more prominent in cells not previously exposed to the gonadotropin in vivo. These findings suggested that IFN-γ is an important physiologic intra-ovarian regulator of follicular atresia and plays a pivotal role in regulation of expression of Fas receptor and subsequent

Site-specific chemical conjugation of human Fas ligand extracellular domain using trans-cyclooctene - methyltetrazine reactions.

PubMed

Muraki, Michiro; Hirota, Kiyonori

2017-07-03

Fas ligand plays a key role in the human immune system as a major cell death inducing protein. The extracellular domain of human Fas ligand (hFasLECD) triggers apoptosis of malignant cells, and therefore is expected to have substantial potentials in medical biotechnology. However, the current application of this protein to clinical medicine is hampered by a shortage of the benefits relative to the drawbacks including the side-effects in systemic administration. Effective procedures for the engineering of the protein by attaching useful additional functions are required to overcome the problem. A procedure for the site-specific chemical conjugation of hFasLECD with a fluorochrome and functional proteins was devised using an inverse-electron-demand Diels-Alder reaction between trans-cyclooctene group and methyltetrazine group. The conjugations in the present study were attained by using much less molar excess amounts of the compounds to be attached as compared with the conventional chemical modification reactions using maleimide derivatives in the previous study. The isolated conjugates of hFasLECD with sulfo-Cy3, avidin and rabbit IgG Fab' domain presented the functional and the structural integrities of the attached molecules without impairing the specific binding activity toward human Fas receptor extracellular domain. The present study provided a new fundamental strategy for the production of the engineered hFasLECDs with additional beneficial functions, which will lead to the developments of the improved diagnostic systems and the effective treatment methods of serious diseases by using this protein as a component of novel molecular tools.

Ferulic Acid Suppresses Glutamate Release Through Inhibition of Voltage-Dependent Calcium Entry in Rat Cerebrocortical Nerve Terminals

PubMed Central

Lin, Tzu Yu; Lu, Cheng Wei; Huang, Shu-Kuei

2013-01-01

Abstract This study investigated the effects and possible mechanism of ferulic acid, a naturally occurring phenolic compound, on endogenous glutamate release in the nerve terminals of the cerebral cortex in rats. Results show that ferulic acid inhibited the release of glutamate evoked by the K+ channel blocker 4-aminopyridine (4-AP). The effect of ferulic acid on the evoked glutamate release was prevented by chelating the extracellular Ca2+ ions, but was insensitive to the glutamate transporter inhibitor DL-threo-beta-benzyl-oxyaspartate. Ferulic acid suppressed the depolarization-induced increase in a cytosolic-free Ca2+ concentration, but did not alter 4-AP–mediated depolarization. Furthermore, the effect of ferulic acid on evoked glutamate release was abolished by blocking the Cav2.2 (N-type) and Cav2.1 (P/Q-type) channels, but not by blocking ryanodine receptors or mitochondrial Na+/Ca2+ exchange. These results show that ferulic acid inhibits glutamate release from cortical synaptosomes in rats through the suppression of presynaptic voltage-dependent Ca2+ entry. PMID:23342970

Leukocyte function-associated antigen-1-dependent lysis of Fas+ (CD95+/Apo-1+) innocent bystanders by antigen-specific CD8+ CTL.

PubMed

Kojima, H; Eshima, K; Takayama, H; Sitkovsky, M V

1997-09-15

Exquisite specificity toward Ag-bearing cells (cognate targets) is one of the most important properties of CD8+ CTL-mediated cytotoxicity. Using highly Ag-specific CD8+ CTL lines and clones, which spare noncognate, Ag-free targets, we found that in the presence of Ag-bearing targets the CTL acquire the ability to lyse noncognate target cells (bystanders). It is shown that the unexpectedly rapid and efficient lysis of bystanders by Ag-activated CTL is mediated by a Fas ligand (FasL)/Fas-based mechanism and does not depend on perforin. The CTL lysed Fas-expressing bystanders, but spared the Fas-negative or anti-Fas mAb-resistant bystander cells. Accordingly, the FasL-deficient gld/gld CTL did not kill bystanders, while perforin-deficient CTL did. Unlike anti-Fas mAb-induced cell death, the lysis of bystanders was not only FasL/Fas dependent but also required adhesion molecule LFA-1 on the surface of the activated CTL. Lysis of bystanders is viewed as acceptable "collateral" damage, but the persistent presence of activated CTL could result in immunopathologies involving functional Fas-expressing tissues.

Compositional similarities of non-solvent extractable fatty acids from recent marine sediments deposited in differing environments

NASA Astrophysics Data System (ADS)

Nishimura, Mitsugu; Baker, Earl W.

1987-06-01

Five recent sediment samples from a variety of North American continental shelves were analyzed for fatty acids (FAs) in the solvent-extractable (SOLEX) lipids as well as four types of non-solvent extractable (NONEX) lipids. The NONEX lipids were operationally defined by the succession of extraction procedure required to recover them. The complete procedure included (i) very mild acid treatment, (ii) HF digestion and (iii) saponification of the sediment residue following exhaustive solvent extraction. The distribution pattern and various compositional parameters of SOLEX FAs in the five sediments were divided into three different groups, indicating the difference of biological sources and also diagenetic factors and processes among the three groups of samples. Nevertheless, the compositions of the corresponding NONEX FAs after acid treatment were surprisingly very similar. This was also true for the remaining NONEX FA groups in the five sediment samples. The findings implied that most of the NONEX FAs reported here are derived directly from living organisms. It is also concluded that a large part of NONEX FAs are much more resistant to biodegradation than we have thought, so that they can form the large percentage of total lipids with increasing depth of water and sediments.

Genetic variability of milk fatty acids.

PubMed

Arnould, V M-R; Soyeurt, H

2009-01-01

The milk fatty acid (FA) profile is far from the optimal fat composition in regards to human health. The natural sources of variation, such as feeding or genetics, could be used to increase the concentrations of unsaturated fatty acids. The impact of feeding is well described. However, genetic effects on the milk FA composition begin to be extensively studied. This paper summarizes the available information about the genetic variability of FAs. The greatest breed differences in FA composition are observed between Holstein and Jersey milk. Milk fat of the latter breed contains higher concentrations of saturated FAs, especially short-chain FAs. The variation of the delta-9 desaturase activity estimated from specific FA ratios could explain partly these breed differences. The choice of a specific breed seems to be a possibility to improve the nutritional quality of milk fat. Generally, the proportions of FAs in milk are more heritable than the proportions of these same FAs in fat. Heritability estimates range from 0.00 to 0.54. The presence of some single nucleotide polymorphisms could explain partly the observed individual genetic variability. The polymorphisms detected on SCD1 and DGAT1 genes influence the milk FA composition. The SCD1 V allele increases the unsaturation of C16 and C18. The DGAT1 A allele is related to the unsaturation of C18. So, a combination of the molecular and quantitative approaches should be used to develop tools helping farmers in the selection of their animals to improve the nutritional quality of the produced milk fat.

Theoretical Analysis of Fas Ligand-Induced Apoptosis with an Ordinary Differential Equation Model.

PubMed

Shi, Zhimin; Li, Yan; Liu, Zhihai; Mi, Jun; Wang, Renxiao

2012-12-01

Upon the treatment of Fas ligand, different types of cells exhibit different apoptotic mechanisms, which are determined by a complex network of biological pathways. In order to derive a quantitative interpretation of the cell sensitivity and apoptosis pathways, we have developed an ordinary differential equation model. Our model is intended to include all of the known major components in apoptosis pathways mediated by Fas receptor. It is composed of 29 equations using a total of 49 rate constants and 13 protein concentrations. All parameters used in our model were derived through nonlinear fitting to experimentally measured concentrations of four selected proteins in Jurkat T-cells, including caspase-3, caspase-8, caspase-9, and Bid. Our model is able to correctly interpret the role of kinetic parameters and protein concentrations in cell sensitivity to FasL. It reveals the possible reasons for the transition between type-I and type-II pathways and also provides some interesting predictions, such as the more decisive role of Fas over Bax in apoptosis pathway and a possible feedback mechanism between type-I and type-II pathways. But our model failed in predicting FasL-induced apoptotic mechanism of NCI-60 cells from their gene-expression levels. Limitations in our model are also discussed. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Inflammation, Apoptosis, and Necrosis Induced by Neoadjuvant Fas Ligand Gene Therapy Improves Survival of Dogs With Spontaneous Bone Cancer

PubMed Central

Modiano, Jaime F; Bellgrau, Donald; Cutter, Gary R; Lana, Susan E; Ehrhart, Nicole P; Ehrhart, EJ; Wilke, Vicki L; Charles, J Brad; Munson, Sibyl; Scott, Milcah C; Pozniak, John; Carlson, Cathy S; Schaack, Jerome; Duke, Richard C

2012-01-01

Fas ligand (FasL) gene therapy for cancer has shown promise in rodents; however, its efficacy in higher mammals remains unknown. Here, we used intratumoral FasL gene therapy delivered in an adenovirus vector (Ad-FasL) as neoadjuvant to standard of care in 56 dogs with osteosarcoma. Tumors from treated dogs had greater inflammation, necrosis, apoptosis, and fibrosis at day 10 (amputation) compared to pretreatment biopsies or to tumors from dogs that did not receive Ad-FasL. Survival improvement was apparent in dogs with inflammation or lymphocyte-infiltration scores >1 (in a 3-point scale), as well as in dogs that had apoptosis scores in the top 50th percentile (determined by cleaved caspase-3). Survival was no different than that expected from standard of care alone in dogs with inflammation scores ≤1 or apoptosis scores in the bottom 50th percentile. Reduced Fas expression by tumor cells was associated with prognostically advantageous inflammation, and this was seen only in dogs that received Ad-FasL. Together, the data suggest that Ad-FasL gene therapy improves survival in a subset of large animals with naturally occurring tumors, and that at least in some tumor types like osteosarcoma, it is most effective when tumor cells fail to express Fas. PMID:22850679

Biowaiver Monographs for Immediate-Release Solid Oral Dosage Forms: Folic Acid.

PubMed

Hofsäss, Martin A; Souza, Jacqueline de; Silva-Barcellos, Neila M; Bellavinha, Karime R; Abrahamsson, Bertil; Cristofoletti, Rodrigo; Groot, D W; Parr, Alan; Langguth, Peter; Polli, James E; Shah, Vinod P; Tajiri, Tomokazu; Mehta, Mehul U; Dressman, Jennifer B

2017-12-01

This work presents a review of literature and experimental data relevant to the possibility of waiving pharmacokinetic bioequivalence studies in human volunteers for approval of immediate-release solid oral pharmaceutical forms containing folic acid as the single active pharmaceutical ingredient. For dosage forms containing 5 mg folic acid, the highest dose strength on the World Health Organization Essential Medicines List, the dose/solubility ratio calculated from solubility studies was higher than 250 mL, corresponding to a classification as "not highly soluble." Small, physiological doses of folic acid (≤320 μg) seem to be absorbed completely via active transport, but permeability data for higher doses of 1-5 mg are inconclusive. Following a conservative approach, folic acid is classified as a Biopharmaceutics Classification System class IV compound until more reliable data become available. Commensurate with its solubility characteristics, the results of dissolution studies indicated that none of the folic acid products evaluated showed rapid dissolution in media at pH 1.2 or 4.5. Therefore, according to the current criteria of the Biopharmaceutics Classification System, the biowaiver approval procedure cannot be recommended for immediate-release solid oral dosage forms containing folic acid. Copyright © 2017 American Pharmacists Association®. All rights reserved.

Functional Polymorphisms of FAS and FASL Gene and Risk of Breast Cancer – Pilot Study of 134 Cases

PubMed Central

Fazaeli, Aliakbar; Eskandari-Nasab, Ebrahim; Arbabi, Farshid; Mashhadi, Mohammad Ali; Taheri, Mohsen; Chaabane, Wiem; Jain, Mayur V.; Łos, Marek J.

2013-01-01

Fas/Fas ligand (FasL) system is one of the key apoptotic signaling entities in the extrinsic apoptotic pathway. De-regulation of this pathway, i.e. by mutations may prevent the immune system from the removal of newly-formed tumor cells, and thus lead to tumor formation. The present study investigated the association between −1377 G/A (rs2234767) and −670 A/G (rs1800682) polymorphisms in Fas as well as single nucleotide polymorphisms INV2nt −124 A/G (rs5030772) and −844 C/T (rs763110) in FasL in a sample of Iranian patients with breast cancer. This case-control study was done on 134 breast cancer patients and 152 normal women. Genomic DNA was extracted from whole blood samples. The polymorphisms were determined by using tetra-ARMS-PCR method. There was no significant difference in the genotype distribution of FAS rs2234767 polymorphism between cases and controls. FAS rs1800682, FASL rs5030772, and FASL rs763110 genotypes showed significant associations with an increasing risk of breast cancer (odds ratio OR = 3.18, P = 0.019; OR = 5.08, P = 0.012; OR = 2.40, P = 0.024, respectively). In conclusion, FAS rs2234767 was not associated with breast cancer risk. Though, FAS rs1800682, FASL rs5030772, and FASL rs763110 polymorphisms were associated with the risk of breast cancer in the examined population. PMID:23326385

Functional polymorphisms in cell death pathway genes FAS and FASL contribute to risk of lung cancer.

PubMed

Zhang, X; Miao, X; Sun, T; Tan, W; Qu, S; Xiong, P; Zhou, Y; Lin, D

2005-06-01

The FAS and FASL system plays a key role in regulating apoptotic cell death and corruption of this signalling pathway has been shown to participate in immune escape and tumorigenesis. There is reduced expression of FAS but elevated expression of FASL in many types of human cancers including lung cancer. We recently reported an association between functional polymorphisms in FAS (-1377G-->A) and FASL (-844T-->C) and risk of oesophageal cancer. To examine the contribution of these polymorphisms to risk of developing lung cancer. Genotypes of 1000 lung cancer patients and 1270 controls were analysed by PCR based restriction fragment length polymorphism. Associations with risk of lung cancer were estimated by logistic regression. Compared with non-carriers, there was a 1.6 fold excess risk of developing lung cancer for carriers of the FAS -1377AA genotype (odds ratio (OR) 1.59, 95% confidence interval (CI) 1.21 to 2.10; p = 0.001), and 1.8 fold excess risk (OR 1.79, 95% CI 1.26 to 2.52; p = 0.001) for carriers of FASL -844CC. Gene-gene interaction of FAS and FASL polymorphisms increased risk of lung cancer in a multiplicative manner (OR for the carriers of both FAS -1377AA and FASL -844CC genotypes 4.18, 95% CI 2.83 to 6.18). Gene-environment interaction of FAS or FASL polymorphism and smoking associated with increased risk of lung cancer was also found. These results are consistent with our initial findings in oesophageal cancer and further support the hypothesis that the FAS and FASL triggered apoptosis pathway plays an important role in human carcinogenesis.

Ursodeoxycholic acid inhibits TNFα-induced IL-8 release from monocytes.

PubMed

O'Dwyer, Aoife M; Lajczak, Natalia K; Keyes, Jennifer A; Ward, Joseph B; Greene, Catherine M; Keely, Stephen J

2016-08-01

Monocytes are critical to the pathogenesis of inflammatory bowel disease (IBD) as they infiltrate the mucosa and release cytokines that drive the inflammatory response. Ursodeoxycholic acid (UDCA), a naturally occurring bile acid with anti-inflammatory actions, has been proposed as a potential new therapy for IBD. However, its effects on monocyte function are not yet known. Primary monocytes from healthy volunteers or cultured U937 monocytes were treated with either the proinflammatory cytokine, TNFα (5 ng/ml) or the bacterial endotoxin, lipopolysaccharide (LPS; 1 μg/ml) for 24 h, in the absence or presence of UDCA (25-100 μM). IL-8 release into the supernatant was measured by ELISA. mRNA levels were quantified by qPCR and changes in cell signaling proteins were determined by Western blotting. Toxicity was assessed by measuring lactate dehydrogenase (LDH) release. UDCA treatment significantly attenuated TNFα-, but not LPS-driven, release of IL-8 from both primary and cultured monocytes. UDCA inhibition of TNFα-driven responses was associated with reduced IL-8 mRNA expression. Both TNFα and LPS stimulated NFκB activation in monocytes, while IL-8 release in response to both cytokines was attenuated by an NFκB inhibitor, BMS-345541. Interestingly, UDCA inhibited TNFα-, but not LPS-stimulated, NFκB activation. Finally, TNFα, but not LPS, induced phosphorylation of TNF receptor associated factor (TRAF2), while UDCA cotreatment attenuated this response. We conclude that UDCA specifically inhibits TNFα-induced IL-8 release from monocytes by inhibiting TRAF2 activation. Since such actions would serve to dampen mucosal immune responses in vivo, our data support the therapeutic potential of UDCA for IBD. Copyright © 2016 the American Physiological Society.

Cystic fibrosis epithelial cells are primed for apoptosis as a result of increased Fas (CD95).

PubMed

Chen, Qiwei; Pandi, Sudha Priya Soundara; Kerrigan, Lauren; McElvaney, Noel G; Greene, Catherine M; Elborn, J Stuart; Taggart, Clifford C; Weldon, Sinéad

2018-02-24

Previous work suggests that apoptosis is dysfunctional in cystic fibrosis (CF) airways with conflicting results. We evaluated the relationship between dysfunctional cystic fibrosis transmembrane conductance regulator (CFTR) and apoptosis in CF airway epithelial cells. Apoptosis and associated caspase activity were analysed in non-CF and CF tracheal and bronchial epithelial cell lines. Basal levels of apoptosis and activity of caspase-3 and caspase-8 were significantly increased in CF epithelial cells compared to controls, suggesting involvement of extrinsic apoptosis signalling, which is mediated by the activation of death receptors, such as Fas (CD95). Increased levels of Fas were observed in CF epithelial cells and bronchial brushings from CF patients compared to non-CF controls. Neutralisation of Fas significantly inhibited caspase-3 activity in CF epithelial cells compared to untreated cells. In addition, activation of Fas significantly increased caspase-3 activity and apoptosis in CF epithelial cells compared to control cells. Overall, these results suggest that CF airway epithelial cells are more sensitive to apoptosis via increased levels of Fas and subsequent activation of the Fas death receptor pathway, which may be associated with dysfunctional CFTR. Copyright © 2018 European Cystic Fibrosis Society. All rights reserved.

A Novel AKT Activator, SC79, Prevents Acute Hepatic Failure Induced by Fas-Mediated Apoptosis of Hepatocytes.

PubMed

Liu, Wei; Jing, Zhen-Tang; Wu, Shu-Xiang; He, Yun; Lin, Yan-Ting; Chen, Wan-Nan; Lin, Xin-Jian; Lin, Xu

2018-05-01

Acute liver failure is a serious clinical problem of which the underlying pathogenesis remains unclear and for which effective therapies are lacking. The Fas receptor/ligand system, which is negatively regulated by AKT, is known to play a prominent role in hepatocytic cell death. We hypothesized that AKT activation may represent a strategy to alleviate Fas-induced fulminant liver failure. We report here that a novel AKT activator, SC79, protects hepatocytes from apoptosis induced by agonistic anti-Fas antibody CH11 (for humans) or Jo2 (for mice) and significantly prolongs the survival of mice given a lethal dose of Jo2. Under Fas-signaling stimulation, SC79 inhibited Fas aggregation, prevented the recruitment of the adaptor molecule Fas-associated death domain (FADD) and procaspase-8 [or FADD-like IL-1β-converting enzyme (FLICE)] into the death-inducing signaling complex (DISC), but SC79 enhanced the recruitment of the long and short isoforms of cellular FLICE-inhibitory protein at the DISC. All of the SC79-induced hepatoprotective and DISC-interruptive effects were confirmed to have been reversed by the Akt inhibitor LY294002. These results strongly indicate that SC79 protects hepatocytes from Fas-induced fatal hepatic apoptosis. The potent alleviation of Fas-mediated hepatotoxicity by the relatively safe drug SC79 highlights the potential of our findings for immediate hepatoprotective translation. Copyright © 2018 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

Exploitable Lipids and Fatty Acids in the Invasive Oyster Crassostrea gigas on the French Atlantic Coast

PubMed Central

Dagorn, Flore; Couzinet-Mossion, Aurélie; Kendel, Melha; Beninger, Peter G.; Rabesaotra, Vony; Barnathan, Gilles; Wielgosz-Collin, Gaëtane

2016-01-01

Economic exploitation is one means to offset the cost of controlling invasive species, such as the introduced Pacific oyster (Crassostrea gigas Thunberg) on the French Atlantic coast. Total lipid and phospholipid (PL) fatty acids (FAs) and sterols were examined in an invasive population of C. gigas in Bourgneuf Bay, France, over four successive seasons, with a view to identify possible sources of exploitable substances. The total lipid level (% dry weight) varied from 7.1% (winter) to 8.6% (spring). Of this, PLs accounted for 28.1% (spring) to 50.4% (winter). Phosphatidylcholine was the dominant PL throughout the year (up to 74% of total PLs in winter). Plasmalogens were identified throughout the year as a series of eleven dimethylacetals (DMAs) with chain lengths between C16 and C20 (up to 14.5% of PL FAs + DMAs in winter). Thirty-seven FAs were identified in the PL FAs. Eicosapentaenoic acid (20:5n-3 EPA/7.53% to 14.5%) and docosahexaenoic acid (22:6n-3 DHA/5.51% to 9.5%) were the dominant polyunsaturated FAs in all seasons. Two non-methylene-interrupted dienoic (NMID) FAs were identified in all seasons: 7,13-docosadienoic and 7,15-docosadienoic acids, the latter being present at relatively high levels (up to 9.6% in winter). Twenty free sterols were identified, including cholesterol at 29.9% of the sterol mixture and about 33% of phytosterols. C. gigas tissues thus contained exploitable lipids for health benefits or as a potential source of high-quality commercial lecithin. PMID:27231919

The Synthetic Triterpenoid CDDO-Im Inhibits Fatty Acid Synthase Expression and Has Antiproliferative and Proapoptotic Effects in Human Liposarcoma Cells

PubMed Central

Hughes, David T.; Martel, Peter M.; Kinlaw, William B.; Eisenberg, Burton L.

2013-01-01

Liposarcomas constitute a rare group of tumors of mesenchymal origin that are often poorly responsive to therapy. This study characterizes a novel human liposarcoma cell line (LiSa-2) and defines the mechanism of its response to a synthetic triterpenoid. Fatty acid synthase (FAS) is a key enzyme of de-novo fatty acid synthesis and is highly expressed in both human liposarcoma tissue specimens and LiSa-2 cells. Treatment of the LiSa-2 cell line with the synthetic triterpenoid 2-cyano-3,12-dioxooleana-1,9-dien-28-oic imidazolide (CDDO-Im) markedly inhibited FAS mRNA expression, FAS protein production and FAS gene promoter activity. As expected, fatty acid synthesis was down regulated, but there was no effect on cellular fatty acid uptake or glycerol-3-phosphate synthesis suggesting a selective inhibition of endogenous fatty acid synthesis. Importantly, CDDO-Im produced a dose-dependent apoptotic effect in the LiSa-2 cell line, and simultaneous treatment with CDDO-Im and the fatty acid synthase inhibitor Cerulenin produced a synergistic cytotoxic effect. Thus, CDDO-Im and Cerulenin act at different loci to inhibit long chain fatty acid synthesis in liposarcoma cells. This study’s demonstration of CDDO-Im inhibition of FAS and Spot 14 (S14) expression is the first report of triterpenoid compounds affecting the fatty acid synthesis pathway. The observed dependence of liposarcomas on lipogenesis to support their growth and survival provides a novel approach to the treatment of liposarcomas with agents that target fatty acid production. PMID:18259941

Lansoprazole protects and heals gastric mucosa from non-steroidal anti-inflammatory drug (NSAID)-induced gastropathy by inhibiting mitochondrial as well as Fas-mediated death pathways with concurrent induction of mucosal cell renewal.

PubMed

Maity, Pallab; Bindu, Samik; Choubey, Vinay; Alam, Athar; Mitra, Kalyan; Goyal, Manish; Dey, Sumanta; Guha, Mithu; Pal, Chinmay; Bandyopadhyay, Uday

2008-05-23

We have investigated the mechanism of antiapoptotic and cell renewal effects of lansoprazole, a proton pump inhibitor, to protect and heal gastric mucosal injury in vivo induced by indomethacin, a non-steroidal anti-inflammatory drug (NSAID). Lansoprazole prevents indomethacin-induced gastric damage by blocking activation of mitochondrial and Fas pathways of apoptosis. Lansoprazole prevents indomethacin-induced up-regulation of proapoptotic Bax and Bak and down-regulation of antiapoptotic Bcl-2 and Bcl(xL) to maintain the normal proapoptotic/antiapoptotic ratio and thereby arrests indomethacin-induced mitochondrial translocation of Bax and collapse of mitochondrial membrane potential followed by cytochrome c release and caspase-9 activation. Lansoprazole also inhibits indomethacin-induced Fas-mediated mucosal cell death by down-regulating Fas or FasL expression and inhibiting caspase-8 activation. Lansoprazole favors mucosal cell renewal simultaneously by stimulating gene expression of prosurvival proliferating cell nuclear antigen, survivin, epidermal growth factor, and basic fibroblast growth factor. The up-regulation of Flt-1 further indicates that lansoprazole activates vascular epidermal growth factor-mediated controlled angiogenesis to repair gastric mucosa. Lansoprazole also stimulates the healing of already formed ulcers induced by indomethacin. Time course study of healing indicates that it switches off the mitochondrial death pathway completely but not the Fas pathway. However, lansoprazole heals mucosal lesions almost completely after overcoming the persisting Fas pathway, probably by favoring the prosurvival genes expression. This study thus provides the detailed mechanism of antiapoptotic and prosurvival effects of lansoprazole for offering gastroprotection against indomethacin-induced gastropathy.

7 CFR 1484.21 - How does FAS determine which Cooperator program applications are approved?

Code of Federal Regulations, 2013 CFR

2013-01-01

... FOREIGN MARKETS FOR AGRICULTURAL COMMODITIES Application and Fund Allocation § 1484.21 How does FAS... that effectively supports the strategic decision-making initiatives of the Government Performance and... creation, expansion, or maintenance of foreign markets, FAS seeks to identify those projects that would...

7 CFR 1484.21 - How does FAS determine which Cooperator program applications are approved?

Code of Federal Regulations, 2012 CFR

2012-01-01

... FOREIGN MARKETS FOR AGRICULTURAL COMMODITIES Application and Fund Allocation § 1484.21 How does FAS... that effectively supports the strategic decision-making initiatives of the Government Performance and... creation, expansion, or maintenance of foreign markets, FAS seeks to identify those projects that would...

7 CFR 1484.21 - How does FAS determine which Cooperator program applications are approved?

Code of Federal Regulations, 2014 CFR

2014-01-01

... FOREIGN MARKETS FOR AGRICULTURAL COMMODITIES Application and Fund Allocation § 1484.21 How does FAS... that effectively supports the strategic decision-making initiatives of the Government Performance and... creation, expansion, or maintenance of foreign markets, FAS seeks to identify those projects that would...

The role of acyl carrier protein isoforms from Cuphea lanceolata seeds in the de-novo biosynthesis of medium-chain fatty acids.

PubMed

Schütt, B S; Brummel, M; Schuch, R; Spener, F

1998-06-01

To investigate the role of acyl carrier protein (ACP) in determining the fate of the acyl moieties linked to it in the course of de-novo fatty acid biosynthesis in higher plants, we carried out in vitro experiments to reconstitute the fatty acid synthase (FAS) reaction in extracts of spinach (Spinacia oleracea L.) leaves, rape (Brassica napus L.) seeds and Cuphea lanceolata Ait. seeds. The action of two major C. lanceolata ACP isoforms (ACP 1 and ACP 2) compared to ACP from Escherichia coli was monitored by saponification of the corresponding FAS products with subsequent analysis of the liberated fatty acids by high-performance liquid chromatography. In a second approach the preference of the medium-chain acyl-ACP-specific thioesterase (EC 3.1.2.14) of C. lanceolata seeds for the hydrolysis of acyl-ACPs prepared from the three ACP types was investigated. Both ACP isoforms from C. lanceolata seeds supported the synthesis of medium-chain fatty acids in a reconstituted FAS reaction of spinach leaf extracts. Compared to the isoform ACP 1, ACP 2 was more effective in supporting the synthesis of such fatty acids in the FAS reaction of rape seed extracts and caused a higher accumulation of FAS products in all experiments. No preference of the medium-chain thioesterase for one specific ACP isoform was observed. The results indicate that the presence of ACP 2 is essential for the synthesis of decanoic acid in C. lanceolata seeds, and its expression in the phase of accumulation of high levels of this fatty acid provides an additional and highly efficient cofactor for stimulating the FAS reaction.

41 CFR 102-38.360 - What must an executive agency do to implement the eFAS program?

Code of Federal Regulations, 2011 CFR

2011-01-01

... agency do to implement the eFAS program? 102-38.360 Section 102-38.360 Public Contracts and Property... must an executive agency do to implement the eFAS program? (a) An executive agency must review the... value added services) of the eFAS SCs. Agencies should give full consideration to sales solutions...

41 CFR 102-38.360 - What must an executive agency do to implement the eFAS program?

Code of Federal Regulations, 2010 CFR

2010-07-01

... agency do to implement the eFAS program? 102-38.360 Section 102-38.360 Public Contracts and Property... must an executive agency do to implement the eFAS program? (a) An executive agency must review the... value added services) of the eFAS SCs. Agencies should give full consideration to sales solutions...

41 CFR 102-38.360 - What must an executive agency do to implement the eFAS program?

Code of Federal Regulations, 2014 CFR

2014-01-01

... agency do to implement the eFAS program? 102-38.360 Section 102-38.360 Public Contracts and Property... must an executive agency do to implement the eFAS program? (a) An executive agency must review the... value added services) of the eFAS SCs. Agencies should give full consideration to sales solutions...

41 CFR 102-38.360 - What must an executive agency do to implement the eFAS program?

Code of Federal Regulations, 2013 CFR

2013-07-01

... agency do to implement the eFAS program? 102-38.360 Section 102-38.360 Public Contracts and Property... must an executive agency do to implement the eFAS program? (a) An executive agency must review the... value added services) of the eFAS SCs. Agencies should give full consideration to sales solutions...

41 CFR 102-38.360 - What must an executive agency do to implement the eFAS program?

Code of Federal Regulations, 2012 CFR

2012-01-01

... agency do to implement the eFAS program? 102-38.360 Section 102-38.360 Public Contracts and Property... must an executive agency do to implement the eFAS program? (a) An executive agency must review the... value added services) of the eFAS SCs. Agencies should give full consideration to sales solutions...

THE EPIDEMIOLOGY OF FETAL ALCOHOL SYNDROME AND PARTIAL FAS IN A SOUTH AFRICAN COMMUNITY

PubMed Central

May, Philip A.; Gossage, J. Phillip; Marais, Anna-Susan; Adnams, Colleen M.; Hoyme, H. Eugene; Jones, Kenneth L.; Robinson, Luther K.; Khaole, Nathaniel C.O.; Snell, Cudore; Kalberg, Wendy O.; Hendricks, Loretta; Brooke, Lesley; Stellavato, Chandra; Viljoen, Denis L.

2007-01-01

OBJECTIVES The prevalence and characteristics of fetal alcohol syndrome (FAS) and partial fetal alcohol syndrome (PFAS) were determined in a third primary school cohort in a community in South Africa (S.A.). METHODS An active case ascertainment, two-tier screening methodology, and the revised Institute of Medicine diagnostic criteria were employed among 818 first grade pupils. Characteristics of children with FAS and PFAS are contrasted with a randomly-selected control group. Data were collected and analyzed for children in the study regarding: 1.) physical growth and development, including dysmorphology, 2.) intelligence and behavioral characteristics, and 3.) their mother’s social, behavioral, and physical characteristics. RESULTS The rate of FAS and PFAS in this area continues as the highest reported in any overall community and is much higher than rates elsewhere. In this cohort it is 68.0 to 89.2 per 1,000. Severe episodic drinking on weekends among mothers of children with FAS and PFAS accounts for 96% of all alcohol consumed. Various measures of maternal drinking are significantly correlated with negative outcomes of children in the areas of non-verbal intelligence (-0.26), verbal intelligence (-0.28), problem behavior (0.31), and overall dysmorphology score (0.59). Significantly more FAS and PFAS exists among children of rural residents (OR = 3.79). CONCLUSIONS A high rate of FAS and PFAS was again documented in this community, and it has increased. Given population similarities, we suspect that other communities in the Western Cape Province of South Africa also have high rates. Programs for prevention are needed. PMID:17127017

Development of the SoFAS (Solid Fats and Added Sugars) Concept: The 2010 Dietary Guidelines for Americans123

PubMed Central

Nicklas, Theresa A; O’Neil, Carol E

2015-01-01

The diets of most US children and adults are poor, as reflected by low diet quality scores, when compared with the recommendations of the Dietary Guidelines for Americans (DGAs). Contributing to these low scores is that most Americans overconsume solid fats, which may contain saturated fatty acids and added sugars; although alcohol consumption was generally modest, it provided few nutrients. Thus, the 2005 DGAs generated a new recommendation: to reduce intakes of solid fats, alcohol, and added sugars (SoFAAS). What precipitated the emergence of the new SoFAAS terminology was the concept of discretionary calories (a “calorie” is defined as the amount of energy needed to increase the temperature of 1 kg of water by 1°C), which were defined as calories consumed after an individual had met his or her recommended nutrient intakes while consuming fewer calories than the daily recommendation. A limitation with this concept was that additional amounts of nutrient-dense foods consumed beyond the recommended amount were also considered discretionary calories. The rationale for this was that if nutrient-dense foods were consumed beyond recommended amounts, after total energy intake was met then this constituted excess energy intake. In the 2010 DGAs, the terminology was changed to solid fats and added sugars (SoFAS); thus, alcohol was excluded because it made a minor contribution to overall intake and did not apply to children. The SoFAS terminology also negated nutrient-dense foods that were consumed in amounts above the recommendations for the specific food groups in the food patterns. The ambiguous SoFAS terminology was later changed to “empty calories” to reflect only those calories from solid fats and added sugars (and alcohol if consumed beyond moderate amounts). The purpose of this review is to provide an historical perspective on how the dietary recommendations went from SoFAAS to SoFAS and how discretionary calories went to empty calories between the 2005

Short-chain fatty acid sensing in rat duodenum

PubMed Central

Akiba, Yasutada; Inoue, Takuya; Kaji, Izumi; Higashiyama, Masaaki; Narimatsu, Kazuyuki; Iwamoto, Ken-ichi; Watanabe, Masahiko; Guth, Paul H; Engel, Eli; Kuwahara, Atsukazu; Kaunitz, Jonathan D

2015-01-01

Intraduodenal fatty acids (FA) and bacterial overgrowth, which generate short-chain FAs (SCFAs), have been implicated in the generation of functional dyspepsia symptoms. We studied the mechanisms by which luminal SCFA perfusion affects duodenal HCO3− secretion (DBS), a measure of mucosal neurohumoral activation. Free fatty acid receptor (FFAR) 1 (FFA1), which binds long-chain FA (LCFA), and SCFA receptors FFA2 and FFA3 were immunolocalised to duodenal enteroendocrine cells. FFA3 colocalised with glucagon-like peptide (GLP)-1, whereas FFA2 colocalised with 5-HT. Luminal perfusion of the SCFA acetate or propionate increased DBS, enhanced by dipeptidyl peptidase-IV (DPPIV) inhibition, at the same time as increasing GLP-2 portal blood concentrations. Acetate-induced DBS was partially inhibited by monocarboxylate/HCO3− exchanger inhibition without affecting GLP-2 release, implicating acetate absorption in the partial mediation of DBS. A selective FFA2 agonist dose-dependently increased DBS, unaffected by DPPIV inhibition or by cholecystokinin or 5-HT3 receptor antagonists, but was inhibited by atropine and a 5-HT4 antagonist. By contrast, a selective FFA1 agonist increased DBS accompanied by GLP-2 release, enhanced by DPPIV inhibition and inhibited by a GLP-2 receptor antagonist. Activation of FFA1 by LCFA and presumably FFA3 by SCFA increased DBS via GLP-2 release, whereas FFA2 activation stimulated DBS via muscarinic and 5-HT4 receptor activation. SCFA/HCO3− exchange also appears to be present in the duodenum. The presence of duodenal fatty acid sensing receptors that signal hormone release and possibly signal neural activation may be implicated in the pathogenesis of functional dyspepsia. PMID:25433076

Association of FAS A-670G Polymorphism and Risk of Uterine Leiomyoma in a Southeast Iranian Population

PubMed Central

Mohammadpour-Gharehbagh, Abbas; Salimi, Saeedeh; Keshavarzi, Farshid; Zakerian, Sepideh; Sajadian, Mojtaba; Mokhtari, Mojgan

2016-01-01

Background: Uterine leiomyoma (UL) is a benign tumor of uterine smooth muscle that affects women in reproductive ages. FAS has an important role in initial stages of apoptosis. Previous studies have shown an association between the FAS gene and tumorigenesis. In the present study, we evaluated the relationship between FAS A-670G (rs 1800682) and UL risk Methods: The FAS gene polymorphism of 155 women with UL and 157 healthy controls was analyzed by the polymerase chain reaction restriction fragment length polymorphism method Results: The AA, AG, and GG genotype frequencies of the FAS A-670G polymorphism were respectively 37.4, 42.6, and 20% in women with UL, and 46, 42.6, and 11.5% in healthy controls. The risk of UL in women was 1.5-fold greater in GG-genotype women than in AA-genotype women. The G allele frequencies were 41% in women with UL and 33% in healthy controls and statistically different (P = 0.03) Conclusion: The FAS polymorphism was associated with the risk of UL in a sample of Iranian women. PMID:28070535

[Experimental study on fas expression of spermatogenic cell in male rats induced by fluorine].

PubMed

Xu, Rui; Shang, Weichao; Liu, Jianmin; Cheng, Xuemin; Ba, Yue; Huang, Hui; Cui, Liuxin

2010-05-01

To research the effect of fluorine on the expression of Fas protein, then study the mechanism of male reproductive toxicity induced by fluoride on molecular level. Thirty Wistar male rats were divided into control group, low-dose group and high-dose group. The NaF dosage for every group were 0,2 and 4g/L. The content of NaF in testis was measured by using fluorine selective electrode. Changes of testosterone and Fas protein were observed using the methods of radioimmunoassay, in situ hybridization. In addition, we observed the quality of spermatozoa. The testis fluoride content of two fluorine treatment groups were higher than that of control group (P < 0.05), and had a dose-dependent effect. The level of testosterone, the number and the livability of the spermatozoon in fluorotic groups were lower than those of control rats (P < 0.05), and the above indexes decreased with the incrase of dosage. The expression of Fas in spermatogenic cells and the sperm aberration of each fluorotic group were higher than control group (P < 0.05), both of them increased with the increase of dosage. Fluorin could reduce the level of serum testosterone, then activated the Fas/FasL system, which caused damage to the reprodutive system.

Effects of soil type and organic fertilizers on fatty acids and vitamin E in Korean ginseng (Panax ginseng Meyer).

PubMed

Chung, Ill-Min; Kim, Jae-Kwang; Yang, Jin-Hee; Lee, Ji-Hee; Park, Sung-Kyu; Son, Na-Young; Kim, Seung-Hyun

2017-12-01

This study examined the effects of soil type and fertilizer regimes on variations in fatty acids (FAs) and vitamin E (Vit-E) in 6-year-old ginseng roots. We observed significant variation in both FA and Vit-E contents owing to the type and quantity of organic fertilizer used in each soil type during cultivation. Unsaturated FAs were approximately 2.7-fold higher in ginseng than in saturated FAs. Linoleic, palmitic, and oleic acids were the most abundant FAs detected in ginseng roots. Additionally, α-tocopherol was the major Vit-E detected. In particular, the increased application of rice straw compost or food waste fertilizer elevated the quantity of nutritionally desirable FAs and bioactive Vit-E in ginseng root. Partial least square-discriminant analysis (PLS-DA) score plots showed that soil type might be the main cause of differences in FA and Vit-E levels in ginseng. Specifically, the PLS-DA model indicated that palmitic acid is a suitable FA marker in determining whether ginseng plants were grown in a paddy-converted field or an upland field. Moreover, linoleic acid levels were highly correlated with α-linolenic acid (r=0.8374; p<0.0001) according to Pearson's correlations and hierarchical clustering analysis. Hence, these preliminary results should prove useful for the reliable production of ginseng containing high phytonutrient quantities according to cultivation conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

Subtype-Specific Radiation Response and Therapeutic Effect of FAS Death Receptor Modulation in Human Breast Cancer.

PubMed

Lee, Chen-Ting; Zhou, Yingchun; Roy-Choudhury, Kingshuk; Siamakpour-Reihani, Sharareh; Young, Kenneth; Hoang, Peter; Kirkpatrick, John P; Chi, Jen-Tsan A; Dewhirst, Mark W; Horton, Janet K

2017-08-01

Breast cancer is the most common malignancy diagnosed among women and represents a heterogeneous group of subtypes. Radiation therapy is a critical component of treatment for breast cancer patients. However, little is known about radiation response among these intrinsic subtypes. In previous studies, we identified a significant induction of FAS after irradiation in biologically favorable breast cancer patients and breast cancer cell lines. Here, we expanded our study and investigated radiation response in a mouse model of breast cancer. MCF7 (luminal), HCC1954 (HER2 + ) or SUM159 (basal) cells were implanted orthotopically into the dorsal mammary fat pad of nude mice. These mice were then treated with different doses of radiation to assess tumor growth control. We further investigated the therapeutic effect of FAS modulation by silencing FAS in radiation-responsive tumors and injecting FAS agonist antibody into radiation-resistant tumors. Exposure to radiation inhibited MCF7, and to a lesser extent HCC1954 tumor growth in a dose-dependent manner. In contrast, SUM159 tumors were resistant to radiation. The estimated TCD 50 values were 19.3 Gy for MCF7 and 44.9 Gy for SUM159. Radiation induced FAS expression in MCF7 tumors, but not SUM159 tumors. We found that silencing of FAS did not negatively impact radiation response in MCF7 tumors, possibly due to compensation by other apoptotic pathways. On the other hand, FAS activating antibody in combination with radiation treatment delayed SUM159 and HCC1954 tumor growth. However, it did not reach statistical significance compared to radiation treatment alone. Our results suggest that there is intrinsic variation in radiation response among breast cancer subtypes. FAS activation concurrent with radiation slows tumor growth in the radiation-resistant subtypes, but the effect was not significant. Alternative subtype-specific modulators of radiation response are under investigation.

Dipicolinic Acid Release by Germinating Clostridium difficile Spores Occurs through a Mechanosensing Mechanism.

PubMed

Francis, Michael B; Sorg, Joseph A

2016-01-01

Classically, dormant endospores are defined by their resistance properties, particularly their resistance to heat. Much of the heat resistance is due to the large amount of dipicolinic acid (DPA) stored within the spore core. During spore germination, DPA is released and allows for rehydration of the otherwise-dehydrated core. In Bacillus subtilis , 7 proteins are encoded by the spoVA operon and are important for DPA release. These proteins receive a signal from the activated germinant receptor and release DPA. This DPA activates the cortex lytic enzyme CwlJ, and cortex degradation begins. In Clostridium difficile , spore germination is initiated in response to certain bile acids and amino acids. These bile acids interact with the CspC germinant receptor, which then transfers the signal to the CspB protease. Activated CspB cleaves the cortex lytic enzyme, pro-SleC, to its active form. Subsequently, DPA is released from the core. C. difficile encodes orthologues of spoVAC , spoVAD , and spoVAE . Of these, the B. subtilis SpoVAC protein was shown to be capable of mechanosensing. Because cortex degradation precedes DPA release during C. difficile spore germination (opposite of what occurs in B. subtilis ), we hypothesized that cortex degradation would relieve the osmotic constraints placed on the inner spore membrane and permit DPA release. Here, we assayed germination in the presence of osmolytes, and we found that they can delay DPA release from germinating C. difficile spores while still permitting cortex degradation. Together, our results suggest that DPA release during C. difficile spore germination occurs though a mechanosensing mechanism. IMPORTANCE Clostridium difficile is transmitted between hosts in the form of a dormant spore, and germination by C. difficile spores is required to initiate infection, because the toxins that are necessary for disease are not deposited on the spore form. Importantly, the C. difficile spore germination pathway