WorldWideScience

Sample records for all-trans retinoic acid-induced

  1. All-trans-retinoic acid-induced pseudotumor cerebri in acute promyelocytic leukemia

    Directory of Open Access Journals (Sweden)

    T. M. Anoop

    2014-01-01

    Full Text Available All-trans-retinoic acid is an integral part in the treatment strategy of acute promyelocytic leukemia (APL. Here we describe a case of pseudotumor cerebri associated with all-trans-retinoic acid (ATRA during the induction therapy in an adult with acute promyelocytic leukemia (APL.

  2. Correlation of HSP110 expression with all-trans retinoic acid-induced apoptosis.

    Science.gov (United States)

    Evrard, L; Vanmuylder, N; Dourov, N; Hermans, C; Biermans, J; Werry-Huet, A; Rooze, M; Louryan, S

    2000-01-01

    In a previous study, we observed the strong expression of a stress protein of the HSP100/Clp family (HSP110) in apoptotic mesectodermal cells during early mouse facial development. In the present study, we describe the strong expression of the same HSP110 in mesectodermal cells undergoing apoptosis after all-trans retinoic acid (RA) administration. We used a teratological model known to increase cell deaths mainly in the first and second branchial arches during mammalian cephalogenesis: the treatment of E9 mouse embryos with all-trans RA, which results in craniofacial malformations comparable to those that characterize mandibulofacial dysostosis in man. Pregnant NMRI mice were treated with 60 mg/kg body weight of all-trans RA, given orally on day 9 of gestation; embryos were taken 4, 12 or 24 hr after RA administration. The apoptotic pattern of RA-induced cell deaths was confirmed using the dUTP biotin nick-end labeling (TUNEL) method and transmission electron microscopy (TEM). HSP110 expression was detected using an immunohistochemical approach. The increase in the number of TUNEL-positive cells and HSP110-positive cells after all-trans RA administration was quantified in the first branchial arch using a computerized method. Twelve hours after RA administration, the increase in the number of HSP110-positive cells is greater than the increase in the number of TUNEL-positive cells. Twenty-four hours after RA administration, only TUNEL-positive cells remain strong in number. We suggest that HSP110 expression could represent a biochemical event of apoptotic cell death induced by RA, associated with early stages of the apoptotic process. In order to find out if HSP110 expression resulted from neosynthesis, we performed in situ hybridization, which demonstrated that the expression of HSP110 occurred at the level of mRNA.

  3. Mechanisms of all-trans retinoic acid-induced differentiation of acute promyelocytic leukemia cells

    Indian Academy of Sciences (India)

    Ji-Wang Zhang; Jian Gu; Zhen-Yi Wang; Sai-Juan Chen; Zhu Chen

    2000-09-01

    Retinoic acids (RA) play a key role in myeloid differentiation through their agonistic nuclear receptors (RAR/RXR) to modulate the expression of target genes. In acute promyelocytic leukemia (APL) cells with rearrangement of retinoic acid receptor (RAR) (including: PML-RAR, PLZF-RAR, NPM-RAR, NuMA-RAR or STAT5b-RAR) as a result of chromosomal translocations, the RA signal pathway is disrupted and myeloid differentiation is arrested at the promyelocytic stage. Pharmacologic dosage of all-trans retinoic acid (ATRA) directly modulates PML-RAR and its interaction with the nuclear receptor co-repressor complex, which restores the wild-type RAR/RXR regulatory pathway and induces the transcriptional expression of downstream genes. Analysing gene expression profiles in APL cells before and after ATRA treatment represents a useful approach to identify genes whose functions are involved in this new cancer treatment. A chronologically well coordinated modulation of ATRA-regulated genes has thus been revealed which seems to constitute a balanced functional network underlying decreased cellular proliferation, initiation and progression of maturation, and maintenance of cell survival before terminal differentiation.

  4. All-trans-retinoic acid induces integrin-independent B-cell adhesion to ADAM disintegrin domains.

    Science.gov (United States)

    Bridges, Lance C; Lingo, Joshuah D; Grandon, Rachel A; Kelley, Melissa D

    2008-04-15

    Cell adhesion is an integral aspect of immunity facilitating extravasation of immune cells during homing and activation. All -trans-Retinoic acid ( t-RA) regulates leukocyte differentiation, proliferation, and transmigration. However, the role of t-RA in immune cell adhesion is poorly defined. In this study, we evaluated the impact of t-RA and its metabolism on B and T cell adhesion. Specifically, we address the impact of t-RA on the adhesive properties of the human mature B and T cell lines RPMI 8866, Daudi and Jurkats. The effect of t-RA exposure on cell adhesion to vascular cell adhesion molecule-1 (VCAM-1), a well-established integrin counter receptor involved in immunity, and to nonconventional ADAM integrin ligands was assessed. We show for the first time that t-RA potently induces B cell adhesion in an integrin-independent manner to both VCAM-1 and select ADAM disintegrin domains. Using retinoid extraction and reverse-phase HPLC analysis, we identify the retinoid that is functionally responsible for this augmented adhesion. We also provide evidence that this novel t-RA adhesive response is not prototypical of lymphocytes since both Daudi and Jurkats do not alter their adhesive properties upon t-RA treatment. Further, the t-RA metabolic profiles between these lineages is distinct with 9- cis-retinoic acid being exclusively detected in Jurkat media. This study is the first to demonstrate that t-RA directly induces B cell adhesion in an integrin-independent manner and is not contingent upon t-RA metabolism.

  5. Elevated TrkA receptor expression is associated with all-trans retinoic acid-induced neuroblastoma differentiation.

    Science.gov (United States)

    Gao, Q; Chen, C F; Dong, Q; Hou, L; Chen, X; Zhi, Y L; Li, X; Lu, H T; Zhang, H Y

    2015-10-27

    Neuroblastoma is the most common and one of the deadliest among pediatric tumors; however, a subset of infants with neuroblastoma display spontaneous regression. The mechanism of spontaneous regression remains to be elucidated. TrkA plays an essential role in the differentiation and functionality of neurons; abundant TrkA expression is associated with favorable prognosis of neuroblastoma. All-trans retinoic acid (ATRA), a first-line drug for acute promyelocytic leukemia (APL) treatment, has been shown to induce differentiation and inhibit cell growth. Neuroblastoma tissues in our hospital inpatient were collected, primary cell culture was performed, and the cells were separated and purified to be cell line. Trypan blue exclusion was used to count the numbers of cells alive, morphological changes were observed under the phase-contrast microscope. RT-PCR was used to determine the expression level of TrkA. In this study, a human neuroblastoma cell line was successfully established; in addition, we demonstrated that ATRA induces growth arrest and promotes the differentiation of neuroblastoma cells. In addition, ATRA was shown to significantly increase the levels of TrkA mRNA expression. Therefore, we concluded that the elevated expression of the TrkA receptor is associated with ATRA-induced growth arrest and differentiation o neuroblastoma cells. The results of this study provide a theoretical basis for the clinical application of differentiation-inducing ATRA for neuroblastoma therapy.

  6. Genome-wide distribution of histone H3 acetylation in all-trans retinoic acid induced neuronal differentiation of SH-SY5Y cells

    Institute of Scientific and Technical Information of China (English)

    FANG HongBo; MI Yang; WU NingHua; ZHANG Ye; SHEN YuFei

    2009-01-01

    With chromatin immunoprecipitation (CHIP) and promoter DNA microarray analyses (ChiP-on-chip), we analyzed the variations of acetylation on histone H3 in all-trans retinoic acid (RA) induced neuronal cell differentiation. Neuroblastoma SH-SY5Y cells were treated with RA for 24 h and the acetylation on histone H3 in the promoter region of the genes was detected. Results showed that, after treatment, the level of acetylation on histone H3 elevated in 597 genes in the genome, and reduced in the other 647 genes compared with those of the control. In summary, we have successfully adopted a high throughput technique to detect and analyze variations of acetylation of histone H3 in human genome at the early phage of RA induced neuronal differentiation of the SH-SY5Y cells.

  7. Epigenetic priming of AML blasts for all-trans retinoic acid-induced differentiation by the HDAC class-I selective inhibitor entinostat.

    Directory of Open Access Journals (Sweden)

    Nadja Blagitko-Dorfs

    Full Text Available All-trans retinoic acid (ATRA has only limited single agent activity in AML without the PML-RARα fusion (non-M3 AML. In search of a sensitizing strategy to overcome this relative ATRA resistance, we investigated the potency of the HDAC class-I selective inhibitor entinostat in AML cell lines Kasumi-1 and HL-60 and primary AML blasts. Entinostat alone induced robust differentiation of both cell lines, which was enhanced by the combination with ATRA. This "priming" effect on ATRA-induced differentiation was at least equivalent to that achieved with the DNA hypomethylating agent decitabine, and could overall be recapitulated in primary AML blasts treated ex vivo. Moreover, entinostat treatment established the activating chromatin marks acH3, acH3K9, acH4 and H3K4me3 at the promoter of the RARβ2 gene, an essential mediator of retinoic acid (RA signaling in different solid tumor models. Similarly, RARβ2 promoter hypermethylation (which in primary blasts from 90 AML/MDS patients was surprisingly infrequent could be partially reversed by decitabine in the two cell lines. Re-induction of the epigenetically silenced RARβ2 gene was achieved only when entinostat or decitabine were given prior to ATRA treatment. Thus in this model, reactivation of RARβ2 was not necessarily required for the differentiation effect, and pharmacological RARβ2 promoter demethylation may be a bystander phenomenon rather than an essential prerequisite for the cellular effects of decitabine when combined with ATRA. In conclusion, as a "priming" agent for non-M3 AML blasts to the differentiation-inducing effects of ATRA, entinostat is at least as active as decitabine, and both act in part independently from RARβ2. Further investigation of this treatment combination in non-M3 AML patients is therefore warranted, independently of RARβ2 gene silencing by DNA methylation.

  8. All-trans retinoic acid in acute promyelocytic leukemia in late pregnancy.

    Science.gov (United States)

    Stentoft, J; Nielsen, J L; Hvidman, L E

    1994-09-01

    All-trans retinoic acid (ATRA) was used in a case of acute promyelocytic leukemia (APL) in late pregnancy. A very prompt maternal risk reduction was achieved with subsequent complete remission and spontaneous delivery of two live children in whom no fetal damage seems to have occurred.

  9. All-trans retinoic acid and rapamycin normalize Hutchinson Gilford progeria fibroblast phenotype.

    Science.gov (United States)

    Pellegrini, Camilla; Columbaro, Marta; Capanni, Cristina; D'Apice, Maria Rosaria; Cavallo, Carola; Murdocca, Michela; Lattanzi, Giovanna; Squarzoni, Stefano

    2015-10-06

    Hutchinson Gilford progeria syndrome is a fatal disorder characterized by accelerated aging, bone resorption and atherosclerosis, caused by a LMNA mutation which produces progerin, a mutant lamin A precursor. Progeria cells display progerin and prelamin A nuclear accumulation, altered histone methylation pattern, heterochromatin loss, increased DNA damage and cell cycle alterations. Since the LMNA promoter contains a retinoic acid responsive element, we investigated if all-trans retinoic acid administration could lower progerin levels in cultured fibroblasts. We also evaluated the effect of associating rapamycin, which induces autophagic degradation of progerin and prelamin A. We demonstrate that all-trans retinoic acid acts synergistically with low-dosage rapamycin reducing progerin and prelamin A, via transcriptional downregulation associated with protein degradation, and increasing the lamin A to progerin ratio. These effects rescue cell dynamics and cellular proliferation through recovery of DNA damage response factor PARP1 and chromatin-associated nuclear envelope proteins LAP2α and BAF. The combined all-trans retinoic acid-rapamycin treatment is dramatically efficient, highly reproducible, represents a promising new approach in Hutchinson-Gilford Progeria therapy and deserves investigation in ageing-associated disorders.

  10. ATRA (all-trans-retinoic acid) syndrome in acute promyelocytic leukemia: clinical and radiologic findings

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Keon Ha; Goo, Jin Mo; Im, Jung Gi; Chung, Myung Jin; Do, Kyung Hyun; Park, Seon Yang [Seoul National Univ. College of Medicine, Seoul (Korea, Republic of); Seo, Joon Beom [Gachon Univ. Medical School, Gil Medical Center, Seoul (Korea, Republic of)

    2001-03-01

    To describe the clinical and radiologic findings of all-trans-retinoic acid (ATRA) syndrome in acute promyelocytic leukemia. Among 21 patients with acute promyelocytic leukemia who were treated with all-trans-retinoic acid between 1995 and 1998, we retrospectively evaluated the cases of four with ATRA syndrome. Two were male and two were female, and their mean age was 58 years. The clinical and radiologic findings of chest radiography (n=4) and HRCT (n=1) were analyzed. Between seven and 13 days after ATRA treatment, dry cough, dyspnea and high fever developed in all patients. The WBC count in peripheral blood was significantly higher [2.9-25.3(mean, 10.8)-fold] than before ATRA treatment, and in all patients, chest radiography revealed ill-defined consolidation and pleural effusion. Kerley's B line (n=3) and hilar enlargement (n=3) were also seen, and in one patient, HRCT demonstrated septal line thickening. Among four patients treated with prednisolone and Ara-C, three recovered and one died. In acute promyelocytic patients treated with all-trans-retinoic acid, radiologic findings of ill-de-fined consolidation, pleural effusion, hilar prominence and Kerley's B line may suggest ATRA syndrome. The early diagnosis of this will improve the patients' prognosis.

  11. Reversible effect of all-trans-retinoic acid on AML12 hepatocyte proliferation and cell cycle progression

    Science.gov (United States)

    The role of all-trans-retinoic acid (atRA) in the regulation of cellular proliferation and differentiation is well documented. Numerous studies have established the cancer preventive propertiesofatRAwhichfunctionstoregulate levels ofcellcycleproteinsessentialfortheGliS transition...

  12. Scrotal ulceration following all-trans retinoic acid therapy for acute promyelocytic leukemia

    Directory of Open Access Journals (Sweden)

    Illias Tazi

    2011-01-01

    Full Text Available All-trans retinoic acid (ATRA induces complete remission in most cases of acute promyelocytic leukemia. Toxicity of ATRA has been shown to be mild, consisting of headache, dry skin, dermatitis, and gastrointestinal disorders. We describe a case of scrotal ulceration with ATRA use in a Moroccan patient, an occurrence that has been rarely reported in the medical literature. The pathogenesis of scrotal ulceration remains unknown. Our experience indicates the importance of recognizing genital ulcers associated with ATRA in order that appropriate countermeasures can be taken.

  13. All-Trans Retinoic Acid plus Arsenic Trioxide versus All-Trans Retinoic Acid plus Chemotherapy for Newly Diagnosed Acute Promyelocytic Leukemia: A Meta-Analysis.

    Directory of Open Access Journals (Sweden)

    Yafang Ma

    Full Text Available Recently, the all-trans retinoic acid (ATRA plus arsenic trioxide (ATO protocol has become a promising first-line therapeutic approach in patients with newly diagnosed acute promyelocytic leukemia (APL, but its benefits compared with standard ATRA plus chemotherapy regimen needs to be proven. Herein, we conducted a meta-analysis comparing the efficacy of ATRA plus ATO with ATRA plus chemotherapy for adult patients with newly diagnosed APL.We systematically searched biomedical electronic databases and conference proceedings through February 2016. Two reviewers independently assessed all studies for relevance and validity.Overall, three studies were eligible for inclusion in this meta-analysis, which included a total of 585 patients, with 317 in ATRA plus ATO group and 268 in ATRA plus chemotherapy group. Compared with patients who received ATRA and chemotherapy, patients who received ATRA plus ATO had a significantly better event-free survival (hazard ratio [HR] = 0.38, 95% confidence interval [CI]: 0.22-0.67, p = 0.009, overall survival (HR = 0.44, 95% CI: 0.24-0.82, p = 0.009, complete remission rate (relative risk [RR] = 1.05; 95% CI: 1.01-1.10; p = 0.03. There were no significant differences in early mortality (RR = 0.48; 95% CI: 0.22-1.05; p = 0.07.Thus, this analysis indicated that ATRA plus ATO protocol may be preferred to standard ATRA plus chemotherapy protocol, particularly in low-to-intermediate risk APL patients. Further larger trials were needed to provide more evidence in high-risk APL patients.

  14. Fungistatic activity of all-trans retinoic acid against Aspergillus fumigatus and Candida albicans

    Directory of Open Access Journals (Sweden)

    Campione E

    2016-04-01

    Full Text Available Elena Campione,1 Roberta Gaziano,2 Daniele Marino,2 Augusto Orlandi3 1Department of Dermatology, 2Department of Microbiology, 3Department of Anatomic Pathology, University of Rome Tor Vergata, Rome, Italy Purpose: Fungal infections are a major complication in hematologic and neoplastic patients causing severe morbidity and mortality. Aspergillus fumigatus and Candida albicans are among the most invasive opportunistic pathogens in immunocompromised patients, and classic antifungal drugs are frequently unsuccessful in these patients. Recent reports hypothesize that the antifungal efficacy of all-trans retinoic acid (ATRA is mainly related to its strong capacity to stimulate monocyte-mediated immunity, but no consideration was given to its potential direct fungistatic activity. Moreover, ATRA offers the opportunity for systemic therapy. Methods and results: We investigated the efficacy of ATRA at different concentrations for its antifungal activity against opportunistic A. fumigatus and C. albicans obtained from clinical samples according to standard protocols. A fungistatic activity of ATRA on A. fumigatus and C. albicans at 0.5–1 mM concentration was documented up to 7 days. Conclusion: This is the first evidence of a direct and strong fungistatic activity of ATRA against A. fumigatus and C. albicans. The potential adjuvant therapeutic application of ATRA might be useful in the treatment and/or prevention of systemic mycoses in immunocompromised patients. The discovery of a direct fungistatic activity, in association with its reported immunomodulatory properties, makes ATRA an excellent candidate for new combined antifungal strategies for systemic mycoses in immunocompromised and cancer patients. Keywords: all-trans retinoic acid, fungistatic activity, fungal infections

  15. All-trans retinoic acid stealth liposomes prevent the relapse of breast cancer arising from the cancer stem cells.

    Science.gov (United States)

    Li, Ruo-Jing; Ying, Xue; Zhang, Yan; Ju, Rui-Jun; Wang, Xiao-Xing; Yao, Hong-Juan; Men, Ying; Tian, Wei; Yu, Yang; Zhang, Liang; Huang, Ren-Jie; Lu, Wan-Liang

    2011-02-10

    The relapse of cancer is mostly due to the proliferation of cancer stem cells which could not be eliminated by a standard chemotherapy. A new kind of all-trans retinoic acid stealth liposomes was developed for preventing the relapse of breast cancer and for treating the cancer in combination with a cytotoxic agent, vinorelbine stealth liposomes. In vitro studies were performed on the human breast cancer MCF-7 and MDA-MB-231 cells. In vivo evaluations were performed on the newly established relapse model with breast cancer stem cells. Results showed that the particle size of all-trans retinoic acid stealth liposomes was approximately 80nm, and the encapsulation efficiency was >90%. Breast cancer stem cells were identified with the CD44(+)/CD24(-) phenotype and characterized with properties: resistant to cytotoxic agent, stronger capability of proliferation, and stronger capability of differentiation. Inhibitory effect of all-trans retinoic acid stealth liposomes was more potent in cancer stem cells than in cancer cells. The mechanisms were defined to be two aspects: arresting breast cancer stem cells at the G(0)/G(1) phase in mitosis, and inducing the differentiation of breast cancer stem cells. The cancer relapse model was successfully established by xenografting breast cancer stem cells into NOD/SCID mice, and the formation and growth of the xenografted tumors were significantly inhibited by all-trans retinoic acid stealth liposomes. The combination therapy of all-trans retinoic acid stealth liposomes with vinorelbine stealth liposomes produced the strongest inhibitory effect to the relapse tumor model. It could be concluded that all-trans retinoic acid stealth liposomes could be used for preventing the relapse of breast cancer by differentiating cancer stem cells and arresting the cell-cycle, and for treating breast cancer as a co-therapy, thus providing a novel strategy for treating breast cancer and preventing relapse derived from breast cancer stem cells.

  16. Heterodimeric BMP-2/7 antagonizes the inhibition of all-trans retinoic acid and promotes the osteoblastogenesis

    NARCIS (Netherlands)

    Bi, W.; Gu, Z.; Zheng, Y.; Zhang, X.; Guo, J.; Wu, G.

    2013-01-01

    Objectives Hypervitaminosis A and alcoholism can result in a low mineral density and compromised regenerative capacity of bone, thus delaying implant osteointegration. The inhibitory effect of all-trans retinoic acid on osteoblastogenesis is considered to be one of the mechanisms. We hypothesized th

  17. All-trans-retinoic acid inhibits tumour growth of malignant pleural mesothelioma in mice.

    Science.gov (United States)

    Tabata, C; Tabata, R; Hirayama, N; Yasumitsu, A; Yamada, S; Murakami, A; Iida, S; Tamura, K; Terada, T; Kuribayashi, K; Fukuoka, K; Nakano, T

    2009-11-01

    Malignant pleural mesothelioma (MPM) is an aggressive malignant tumour of mesothelial origin associated with asbestos exposure. Because MPM has limited response to conventional chemotherapy and radiotherapy, the prognosis is very poor. Several researchers have reported that cytokines such as interleukin (IL)-6 play an important role in the growth of MPM. Previously, it was reported that all-trans-retinoic acid (ATRA) inhibited the production and function of IL-6 and transforming growth factor (TGF)-beta1 in experiments using lung fibroblasts. We investigated whether ATRA had an inhibitory effect on the cell growth of MPM, the origin of which was mesenchymal cells similar to lung fibroblasts, using a subcutaneous xenograft mouse model. We estimated the tumour growth and performed quantitative measurements of IL-6, TGF-beta1 and platelet-derived growth factor (PDGF) receptor (PDGFR)-beta mRNA levels both of cultured MPM cells and cells grown in mice with or without the administration of ATRA. ATRA significantly inhibited MPM tumour growth. In vitro studies disclosed that the administration of ATRA reduced 1) mRNA levels of TGF-beta1, TGF-beta1 receptors and PDGFR-beta, and 2) TGF-beta1-dependent proliferation and PDGF-BB-dependent migration of MPM cells. These data may provide a rationale to explore the clinical use of ATRA for the treatment of MPM.

  18. Genital ulcers during treatment with ALL-trans retinoic acid for acute promyelocytic leukemia.

    Science.gov (United States)

    Fukuno, Kenji; Tsurumi, Hisashi; Goto, Hideko; Oyama, Masami; Tanabashi, Shinobu; Moriwaki, Hisataka

    2003-11-01

    Scrotal ulcer is a unique adverse effect of all-trans retinoic acid (ATRA) in patients with acute promyelocytic leukemia (APL). The pathogenesis of scrotal ulceration remains unknown. We describe genital ulcers that developed in four patients with APL who were undergoing ATRA therapy (45 mg/m2 per day p.o.). Two of the patients were female, in whom this condition is quite rare. Genital ulcers with concomitant fever appeared between 17 and 32 days of therapy in all four patients. Genital ulcers healed in three of the patients while another patient developed Fournier's gangrene and underwent left testectomy. Ulcer healing was brought by either local or intravenous corticosteroids. Intravenous dexamethasone actually enabled continued ATRA administration in one patient, while ATRA was discontinued in other two patients. If corticosteroids cannot control progression of genital ulcers nor concomitant fever, ATRA administration should be discontinued so as not to induce Fournier's gangrene nor retionic acid syndrome. Our experience indicates the importance of recognizing genital ulcers associated with ATRA in order that appropriate countermeasures can be taken.

  19. Inhibition of matrix metalloproteinases expression in human dental pulp cells by all-trans retinoic acid

    Institute of Scientific and Technical Information of China (English)

    Jin Man Kim; Sang Wook Kang; Su-Mi Shin; Duck Su Kim; Kyong-Kyu Choi; Eun-Cheol Kim; Sun-Young Kim

    2014-01-01

    All-trans retinoic acid (ATRA) inhibits matrix metalloproteinase (MMP)-2 and MMP-9 in synovial fibroblasts, skin fibroblasts, bronchoalveolar lavage cells and cancer cells, but activates MMP-9 in neuroblast and leukemia cells. Very little is known regarding whether ATRA can activate or inhibit MMPs in human dental pulp cells (HDPCs). The purpose of this study was to determine the effects of ATRA on the production and secretion of MMP-2 and-9 in HDPCs. The productions and messenger RNA (mRNA) expressions of MMP-2 and-9 were accessed by gelatin zymography and real-time polymerase chain reaction (PCR), respectively. ATRA was found to decrease MMP-2 level in a dose-dependent manner. Significant reduction in MMP-2 mRNA expression was also observed in HDPCs treated with 25 mmol?L21 ATRA. However, HDPCs treated with ATRA had no effect on the pattern of MMP-9 produced or secreted in either cell extracts or conditioned medium fractions. Taken together, ATRA had an inhibitory effect on MMP-2 expression in HDPCs, which suggests that ATRA could be a candidate as a medicament which could control the inflammation of pulp tissue in vital pulp therapy and regenerative endodontics.

  20. Pathophysiology, clinical features and radiological findings of differentiation syndrome/all-trans-retinoic acid syndrome

    Institute of Scientific and Technical Information of China (English)

    Luciano; Cardinale; Francesco; Asteggiano; Federica; Moretti; Federico; Torre; Stefano; Ulisciani; Carmen; Fava; Giovanna; Rege-Cambrin

    2014-01-01

    In acute promyelocytic leukemia, differentiation thera-py based on all-trans-retinoic acid can be complicated by the development of a differentiation syndrome(DS). DS is a life-threatening complication, characterized by respiratory distress, unexplained fever, weight gain, interstitial lung infiltrates, pleural or pericardial effusions, hypotension and acute renal failure. The diagnosis of DS is made on clinical grounds and has proven to be difficult, because none of the symptoms is pathognomonic for the syndrome without any definitive diagnostic criteria. As DS can have subtle signs and symptoms at presentation but progress rapidly, end-stage DS clinical picture resembles the acute respiratory distress syndrome with extremely poor prognosis; so it is of absolute importance to be conscious of these complications and initiate therapy as soon as it was suspected. The radiologic appearance resembles the typical features of cardiogenic pulmonary edema. Diagnosis of DS remains a great skill for radiologists and haematologist but it is of an utmost importance the cooperation in suspect DS, detect the early signs of DS, examine the patients’ behaviour and rapidly detect the complications.

  1. Gangrenous cheilitis associated with all-trans retinoic acid therapy for acute promyelocytic leukemia.

    Science.gov (United States)

    Tanaka, Mariko; Fukushima, Noriyasu; Itamura, Hidekazu; Urata, Chisako; Yokoo, Masako; Ide, Masaru; Hisatomi, Takashi; Tomimasu, Rika; Sueoka, Eisaburo; Kimura, Shinya

    2010-01-01

    A 67-year-old Japanese woman who presented with erythema on the abdomen and pancytopenia was found to have acute promyelocytic leukemia (APL). A skin biopsy revealed invasion of APL cells. She was started on induction treatment with all-trans retinoic acid (ATRA) at 45 mg/m(2). On day 4, the leukemic cell number had increased to over 1.0 x 10(9)/L. Consequently, chemotherapy with idarubicin and cytarabine was initiated. On day 10, dryness of the lips appeared. The lower lip swelled and developed painful black eschars. A high fever was also present. Despite discontinuing ATRA on day 20 and administering antibiotics, an anti-fungal agent and valaciclovir, these signs did not improve. Histopathologically, the biopsied lip revealed infiltration of neutrophils and vasculitis. The patient was given ATRA on days 29 and 30 due to an increase in APL cell numbers, after which the gangrenous cheilitis extended over the whole lip. On day 49, the patient was started on re-induction treatment with arsenic trioxide. She achieved complete remission and the gangrenous cheilitis slowly healed over the following 8 weeks. Since the clinical features of the gangrenous cheilitis in this case were similar to those of ATRA-associated scrotal ulcers, it appears that activated neutrophils derived from differentiated APL cells may have caused the gangrenous cheilitis. Physicians should be alert to the development of gangrenous cheilitis during treatment with ATRA.

  2. Modulation of human stratum corneum properties by salicylic acid and all-trans-retinoic acid.

    Science.gov (United States)

    Piérard-Franchimont, C; Goffin, V; Piérard, G E

    1998-01-01

    Topical all-trans-retinoic acid (RA) has been reported to decrease the in vivo skin response to sodium lauryl sulfate (SLS). The converse was also shown with a synergistic effect of RA following prior applications of SLS. The reason for such effects is not clear. We employed measures of transepidermal water loss (TEWL), squamometry and sequential corneosurfametry to explore the protective activity of a 0.05% RA cream at the level of the stratum corneum. Nonionic oil-in-water emulsions with or without 5% salicylic acid (SA) served as test product references. Data indicated that the RA formulation was responsible for a stochastic impairment in the TEWL and for an increased intercorneocyte cohesion. SA and the unmedicated emulsion did not lead to similar TEWL changes. The squamometry test proved to be very sensitive to disclose the effects of SA and RA without, however, allowing to distinguish the difference in the physiological processes involved. The corneosurfametry bioassay did not show any protection or synergistic effect between RA or SA and SLS challenge on the stratum corneum. This is in contrast to a previous work showing a positive protective effect afforded by retinol against SLS. The combined effects of irritant compounds affecting the stratum corneum are complex. The precise reason for some of their biological consequences remains a conundrum. On balance, products such as SA and RA do not appear to afford protection or impairment to a surfactant challenge at the level of the stratum corneum.

  3. Heterodimeric BMP-2/7 antagonizes the inhibition of all-trans retinoic acid and promotes the osteoblastogenesis.

    Directory of Open Access Journals (Sweden)

    Wenjuan Bi

    Full Text Available OBJECTIVES: Hypervitaminosis A and alcoholism can result in a low mineral density and compromised regenerative capacity of bone, thus delaying implant osteointegration. The inhibitory effect of all-trans retinoic acid on osteoblastogenesis is considered to be one of the mechanisms. We hypothesized that heterodimeric bone morphogenetic protein-2/7 could antagonize all-trans retinoic acid and enhance osteoblastogenesis, with an aim to accelerate and enhance bone regeneration and implant osteointegration. MATERIALS AND METHODS: We applied 5 ng/ml or 50 ng/ml bone morphogenetic protein-2/7 to restore the osteoblastogenesis of pre-osteoblasts (MC3T3-E1 cell line that was inhibited by 1 µM all-trans retinoic acid. We evaluated the efficacy by assessing cell numbers (proliferation, alkaline phosphatase activity (a marker for early differentiation, osteocalcin (a marker for late differentiation, calcium deposition (a marker for final mineralization and the expression of osteoblastogenic genes (such as Runx2, Collagen Ia, alkaline phosphatase and osteocalcin at different time points. RESULTS: All-trans retinoic acid significantly inhibited the expression of all the tested osteoblastogenic genes and proteins except alkaline phosphatase activity. In the presence of ATRA, 50 ng/ml bone morphogenetic protein-2/7 not only completely restored but also significantly enhanced all the osteoblastogenic genes and proteins. On the 28(th day, mineralization was completely inhibited by all-trans retinoic acid. In contrast, 50 ng/ml BMP-2/7 could antagonize ATRA and significantly enhance the mineralization about 2.5 folds in comparison with the control treatment (no ATRA, no BMP2/7. CONCLUSIONS: Heterodimeric bone morphogenetic protein-2/7 bears a promising application potential to significantly promote bone regeneration and implant osteointegration for the patients with hypervitaminosis A and alcoholism.

  4. All-trans retinoic acid potentiates cisplatin-induced kidney injury in rats: impact of retinoic acid signaling pathway.

    Science.gov (United States)

    Elsayed, Abdelrahman M; Abdelghany, Tamer M; Akool, El-Sayed; Abdel-Aziz, Abdel-Aziz H; Abdel-Bakky, Mohamed S

    2016-03-01

    Cisplatin (cis-diammine dichloroplatinum (II), CDDP) is a widely used drug for treatment of various types of cancers. However, CDDP-induced nephrotoxicity remains the main dose-limiting side effect. Retinoids are a group of vitamin A-related compounds that exert their effects through retinoid receptors activation. In this study, we investigated the effect of CDDP treatment on retinoic acid receptor-α (RAR-α) and retinoid X receptor-α (RXR-α) expression. In addition, we investigated the possible modulatory effects of RAR agonist, all-trans retinoic acid (ATRA), on CDDP-induced nephrotoxicity. Rats were treated with saline, DMSO, CDDP, ATRA, or CDDP/ATRA. Twenty-four hours after the last ATRA injection, rats were killed; blood samples were collected; kidneys were dissected; and biochemical, immunohistochemical, and histological examinations were performed. Our results revealed that CDDP treatment significantly increased serum levels of creatinine and urea, with concomitant decrease in serum albumin. Moreover, reduced glutathione (GSH) content as well as superoxide dismutase (SOD) and catalase (CAT) activities were significantly reduced with concurrent increase in kidney malondialdehyde (MDA) content following CDDP treatment. Furthermore, CDDP markedly upregulated tubular RAR-α, RXR-α, fibrin, and inducible nitric oxide synthase (iNOS) protein expression. Although administration of ATRA to control rats did not produce marked alterations in kidney function parameters, administration of ATRA to CDDP-treated rats significantly exacerbated CDDP-induced nephrotoxicity. In addition, CDDP/ATRA co-treatment significantly increased RAR-α, RXR-α, fibrin, and iNOS protein expression compared to CDDP alone. In conclusion, we report, for the first time, the crucial role of retinoid receptors in CDDP-induced nephrotoxicity. Moreover, our findings indicate that co-administration of ATRA with CDDP, although beneficial on the therapeutic effects, their deleterious effects on

  5. Effect of All-trans Retinoic Acid on Airway Inflammation in Asthmatic Rats and Its Mechanism

    Institute of Scientific and Technical Information of China (English)

    方红; 金红芳; 王宏伟

    2004-01-01

    Summary: The inhibitive effects of all-trans retinoic acid (ARTA) on airway inflammation in asthmatic rats and its mechanism on the basis of the regulation of nuclear factor kappaB (NF-κB) were explored. Thirty-two SD rats were randomly divided into 4 groups: control group, asthma group,dexamethasone treatment group and retinotic acid treatment group. The total and differential cell counts in the collected bronchoalveolar lavage fluid (BALF) were measured. The pathological changes in lung tissues were estimated by scoring. The expression of NF-κB inhibitor (IκBa), NF-κB,intercellular adhering molecule-1 (ICAM-1) in lung tissue was detected by immunohistochemical method. The results showed that in the two treatment groups, the total cell counts and proportion of inflammatory cells in BALF were significantly reduced, but there was no significant difference in differential cell counts in BALF between, them. The pathological changes in lung tissues in the treatment groups were significantly attenuated as compared with asthma group. Except the epithelial injury in retinotic acid treatment group was milder than in dexamethasone treatment group, the remaining lesions showed no significant difference between them. In the two treatment groups, the expression of IκBa was increased, while the expression of NF-κB and ICAM-1 decreased with the difference between the two groups being not significant. It was concluded that the similar anti-inflammatory effects and mechanism of ATRA on airway in asthmatic rats to those of dexamethasone were contributed to the increase of cytoplasmic IκBa content and suppression of NF-cB activation and expression.

  6. Effect of All-Trans Retinoic Acid on the Pancreas of Streptozotocin-Induced Diabetic Rat.

    Science.gov (United States)

    Eltony, Sohair A; Elmottaleb, Nashwa A; Gomaa, Asmaa M; Anwar, Mamdouh M; El-Metwally, Tarek H

    2016-03-01

    All-trans Retinoic acid (atRA) is instructive for the development of endocrine pancreas and is an integral component of β-cell induction protocols. We showed that atRA induces glucose-responsive endocrine transdifferentiation of pleomorphic pancreatic ductal adenocarcinoma cells in vitro. This study aimed to detect the role of atRA in improving the histological changes of the pancreas in diabetic rats. Forty young male Wistar rats were used and divided into three groups. Group I: normal vehicle control (N = 5). Group II: streptozotocin-induced diabetic rats (N = 20) were followed up at 0.0, 1, 2, and 4 weeks. Group III: streptozotocin-induced diabetic rats (N = 15) treated with atRA (2.5 mg/kg/day), were followed up at 1, 2, and 4 weeks. Specimens from the pancreas were processed for light, electron microscopy and pancreatic insulin mRNA expression. Blood samples were assayed for the levels of glucose, insulin, and total peroxides. In the atRA-treated group, the number of the islets and the islet area significantly increased. Strong insulin-immunoreactive endocrine-like cells were observed nearby the pancreatic acini and the interlobular ducts. Interestingly, insulin-positive cells seemed to arise from pancreatic acinar and ductal epithelium. Ultrastructurally, ß-cells, acinar, and ductal cells restored their normal appearance. Pancreatic insulin mRNA and blood indices were almost normalized. AtRA improved the histological changes of the pancreas and the blood indices in diabetic rats.

  7. All-TRANS RETINOIC ACID INTERFERES DEVELOPMENT OF PULMONARY HYPERTENSION INDUCED BY MONOCROTALINE IN RATS

    Institute of Scientific and Technical Information of China (English)

    秦玉明; 周爱卿; 贲晓明; 沈捷; 梁瑛; 李奋

    2001-01-01

    Objective To determine whether all-trans retinoic acid (atRA) affects the metabolism of collagen in main pulmonary artery and exerts an inhibitory effect in rats with pulmonary hypertension induced by monocrotaline . Methods All rats (n=72) were divided into 3 groups as control, model, and atRA . In model and atRA groups, rats (n=48) were assigned at random to be given a single subcutaneous injection of monocrotaline (60mgg/kg) and administrated with either atRA (30rng·kg-1·d-1) for atRA group or saline through oral-gastro intubation for model group. In control group, rats (n=24) received a single subcutaneous injection of an equal volume of 0. 9% saline. On day 7, 14,21 and 28 after monocrotaline or saline injection, cardiovascular catheters were inserted into the pulmonary artery of rats in each group to examine their mean pulmonary artery pressure, in addition with their hydroxyproline content determined by chromometry. Results In comparison with the control rats, the mean pulmonary artery pressure of rats in model group increased significantly on day 21 and up to the peak on day 28 (P<0.01), while their hydroxyproline contents decreased significantly on day 14 ( P < 0.05) and increased significantly on day 21 and 28. The atRA group when compared with the model group show reduction in the content of hydroxyproline and the mean pulmonary artery pressure ( P < 0.01 ). Conclusion The atRA inhibits the accumulation of collagen in main pulmonary artery and interferes the development of pulmonary hypertension which might elicit favorable geometric remodeling of rat pulmonary hypertension induced by monocrotaline.

  8. Redox balance influences differentiation status of neuroblastoma in the presence of all-trans retinoic acid.

    Science.gov (United States)

    Silvis, Anne M; McCormick, Michael L; Spitz, Douglas R; Kiningham, Kinsley K

    2016-04-01

    Neuroblastoma is the most common extra-cranial solid tumor in childhood; and patients in stage IV of the disease have a high propensity for tumor recurrence. Retinoid therapy has been utilized as a means to induce differentiation of tumor cells and to inhibit relapse. In this study, the expression of a common neuronal differentiation marker [neurofilament M (NF-M)] in human SK-N-SH neuroblastoma cells treated with 10μM all-trans retinoic acid (ATRA) showed significantly increased expression in accordance with reduced cell number. This was accompanied by an increase in MitoSOX and DCFH2 oxidation that could be indicative of increased steady-state levels of reactive oxygen species (ROS) such as O2(•-) and H2O2, which correlated with increased levels of MnSOD activity and immuno-reactive protein. Furthermore PEG-catalase inhibited the DCFH2 oxidation signal to a greater extent in the ATRA-treated cells (relative to controls) at 96h indicating that as the cells became more differentiated, steady-state levels of H2O2 increased in the absence of increases in peroxide-scavenging antioxidants (i.e., glutathione, glutathione peroxidase, and catalase). In addition, ATRA-induced stimulation of NF-M at 48 and 72h was enhanced by decreasing SOD activity using siRNA directed at MnSOD. Finally, treatment with ATRA for 96h in the presence of MnSOD siRNA or PEG-catalase inhibited ATRA induced increases in NF-M expression. These results provide strong support for the hypothesis that changes in steady-state levels of O2(•-) and H2O2 significantly contribute to the process of ATRA-induced differentiation in neuroblastoma, and suggest that retinoid therapy for neuroblastoma could potentially be enhanced by redox-based manipulations of superoxide metabolism to improve patient outcome.

  9. Genital Ulcer Development in Patients with Acute Promyelocytic Leukaemia Treated with All-Trans Retinoic Acid: A Case Series

    Directory of Open Access Journals (Sweden)

    Mohammed Al Huneini

    2013-05-01

    Full Text Available We report here four cases of genital ulcers that developed after the administration of all-trans retinoic acid (ATRA for the treatment of acute promyelocytic leukemia (APL. Between October 2007 and March 2010, three males and one female (age range 19-35 years were identified to have genital ulcers after being prescribed all-trans retinoic acid (ATRA as a part of chemotherapy for APL. This is the first series of cases describing genital ulcers, as a unique and rare complication of ATRA used for treatment of APL in these patients, with no other cause identified. Following temporary cessation of ATRA for a few days in these three cases, improvement of the ulcers was noted.

  10. Identification of target genes of transcription factor CEBPB in acute promyelocytic leukemia cells induced by all-trans retinoic acid

    Institute of Scientific and Technical Information of China (English)

    Lei Yu; Yang-De Zhang; Jun Zhou; De-Ming Yao; Xiang Li

    2013-01-01

    Objective: To indentify target genes of transcription factor CCAAT enhancer-binding proteinβ (CEBPB) in acute promyelocytic leukemia cells induced by all-trans retinoic acid. Methods:A new strategy for high-throughput identification of direct target genes was established by combining chromatin immunoprecipitation (ChIP) with in vitro selection. Then, 106 potential CEBPB binding fragments from the genome of the all-trans retinoic acid (ATRA)-treated NB4 cells were identified. Results: Of them, 82 were mapped in proximity to known or previously predicted genes; 7 were randomly picked up for further confirmation by ChIP-PCR and 3 genes (GALM, ITPR2 and ORM2) were found to be specifically up-regulated in the ATRA-treated NB4 cells, indicating that they might be the down-stream target genes of ATRA. Conclusions: Our results provided new insight into the mechanisms of ATRA-induced granulocytic differentiation.

  11. Potential role of nuclear receptor ligand all-trans retinoic acids in the treatment of fungal keratitis

    Institute of Scientific and Technical Information of China (English)

    Hong-Yan; Zhou; Wei; Zhong; Hong; Zhang; Miao-Miao; Bi; Shuang; Wang; Wen-Song; Zhang

    2015-01-01

    ·Fungal keratitis(FK) is a worldwide visual impairment disease. This infectious fungus initiates the primary innate immune response and, later the adaptive immune response. The inflammatory process is related to a variety of immune cells, including macrophages, helper T cells, neutrophils, dendritic cells, and Treg cells, and is associated with proinflammatory, chemotactic and regulatory cytokines. All-trans retinoic acids(ATRA)have diverse immunomodulatory actions in a number of inflammatory and autoimmune conditions. These retinoids regulate the transcriptional levels of target genes through the activation of nuclear receptors.Retinoic acid receptor α(RAR α), retinoic acid receptor γ(RAR γ), and retinoid X receptor α(RXR α) are expressed in the cornea and immune cells. This paper summarizes new findings regarding ATRA in immune and inflammatory diseases and analyzes the perspective application of ATRA in FK.

  12. Outcome of pregnancy in women treated with all-trans retinoic acid; a case report and review of literature.

    Science.gov (United States)

    Valappil, Saudabi; Kurkar, Micheal; Howell, Rosemary

    2007-10-01

    All-trans-retinoic acid (ATRA) has been proved to be an effective treatment for acute promyelocytic leukemia (APL), inducing remission in more than 90% of cases. Treatment of APL in pregnancy is controversial as the use of ATRA has been questioned due to the teratogenic effect of retinoids. We report a case of pregnancy in a woman exposed to ATRA during the first trimester. The baby was born healthy, without any anomalies. Review of all reported cases of the use of ATRA in pregnancy revealed no serious adverse outcomes or congenital anomalies although only very few cases had exposure in the first trimester.

  13. Incidence of secondary neoplasms in patients with acute promyelocytic leukemia treated with all-trans retinoic acid plus chemotherapy or with all-trans retinoic acid plus arsenic trioxide.

    Science.gov (United States)

    Eghtedar, Alireza; Rodriguez, Ildefonso; Kantarjian, Hagop; O'Brien, Susan; Daver, Naval; Garcia-Manero, Guillermo; Ferrajoli, Alessandra; Kadia, Tapan; Pierce, Sherry; Cortes, Jorge; Ravandi, Farhad

    2015-05-01

    The incidence and pattern of secondary neoplasms in patients with acute promyelocytic leukemia (APL) treated with all-trans retinoic acid (ATRA)-containing regimens is not well described. We compared 160 patients with APL treated with ATRA plus idarubicin (n = 54) or ATRA plus arsenic trioxide (ATO) (n = 106) for the incidence of secondary cancers per unit time of follow-up. Median follow-up times for the two cohorts were 136 and 29 months, respectively. Nine patients developed secondary cancers in the chemotherapy group. These included two breast cancers, three myelodysplastic syndromes/acute myeloid leukemia, one vulvar cancer, one prostate cancer, one colon cancer and one soft tissue sarcoma. A melanoma and one pancreatic cancer developed in the ATO group. We conclude that treatment of patients with APL using the non-chemotherapy regimen of ATRA plus ATO is not associated with a higher incidence of secondary cancers (p = 0.29) adjusted for unit time of exposure.

  14. Chronic oral treatment with 13-cis-retinoic acid (isotretinoin) or all-trans-retinoic acid does not alter depression-like behaviors in rats.

    Science.gov (United States)

    Ferguson, Sherry A; Cisneros, F Javier; Gough, B; Hanig, Joseph P; Berry, Kimberly J

    2005-10-01

    Oral treatment with the anti-acne drug Accutane (isotretinoin, 13-cis-retinoic acid) has been associated with suicide ideation and depression. Here, depression-like behaviors (i.e., behavioral despair and anhedonia) were quantified in adult Sprague-Dawley rats gavaged daily beginning at postnatal day (PND) 82 with 13-cis-RA (7.5 or 22.5 mg/kg) or all-trans-retinoic acid (10 or 15 mg/kg ). Tested at PND 130-131 in the Forced Swim Test, 7.5 mg/kg 13-cis-RA marginally decreased immobility and slightly increased climb/struggle durations whereas neither all-trans-retinoic acid group differed from controls. Voluntary saccharin solution (0.03%) intake at PND 102-104 and PND 151-153 was not different from controls in any treated group, although all RA-treated groups had lower intakes. Swim speed in a water maze at PND 180 was similar across groups, indicating no RA-induced differences in physical ability. Open field activity was mildly decreased at PND 91 in 7.5 mg/kg-treated males only, but it was within the control range at PND 119, 147, and 175. Thus, at serum levels similar to those in humans receiving the drug, chronic 13-cis-RA treatment did not severely affect depression-like behaviors in rats. These data do not substantiate the hypothesis of 13-cis-RA-induced depression.

  15. All-trans retinoic acid increases oxidative metabolism in mature adipocytes

    DEFF Research Database (Denmark)

    Mercader, Josep; Madsen, Lise; Felipe, Francisco;

    2007-01-01

    BACKGROUND/AIMS: In rodents, retinoic acid (RA) treatment favors loss of body fat mass and the acquisition of brown fat features in white fat depots. In this work, we sought to examine to what extent these RA effects are cell autonomous or dependent on systemic factors. METHODS: Parameters of lipid...... preceded by an early RA-induced phosphorylation of p38 mitogen-activated protein kinase. UCP1 expression was not induced. CONCLUSION: The results indicate that RA directly favors remodeling of mature 3T3-L1 adipocytes in culture toward increased oxidative metabolism....

  16. Phytanic acid and docosahexaenoic acid increase the metabolism of all-trans-retinoic acid and CYP26 gene expression in intestinal cells.

    Science.gov (United States)

    Lampen, A; Meyer, S; Nau, H

    2001-10-31

    Retinoids are essential for growth and cell differentiation of epithelial tissues. The effects of the food compounds phytol, the phytol metabolite phytanic acid, and the fatty acid docosahexaenoic acid (DHA) on the retinoid signaling pathway in intestinal cells were studied. Phytol inhibited the formation of all-trans-retinoic acid (RA) from dietary retinol in intestinal cells. Phytanic acid, a known retinoic X receptor (RXRalpha) and peroxisome proliferator activating receptor (PPARalpha) activator, also activated PPARdelta, and to a lesser degree PPARgamma, in a transactivation assay. Phytanic acid had no effect on intestinal RA hydroxylase CYP26 (also named P450RAI) gene expression and metabolism of all-trans-RA in intestinal Caco-2 cells. However, in combination with retinoic acid receptor (RAR)-ligands (all-trans-RA or synthetic Am580) phytanic acid enhanced the induction of CYP26 and RA-metabolism in comparison to treatments with all-trans-RA or Am580 alone. Also treatment with DHA did not affect CYP26 gene expression and RA-metabolism but cotreatment of the cells with DHA and all-trans-RA or Am580 enhanced the induction of CYP26, in comparison to the induction caused by all-trans-RA or Am580 alone. This study indicates that food compounds such as phytanic acid and DHA that are RXR-agonists and have an impact on intestinal CYP26 gene expression and metabolism of all-trans-RA in intestinal cells.

  17. Genital ulcers after treatment with all-trans-retinoic acid in a child with acute promyelocytic leukemia.

    Science.gov (United States)

    Unal, Selma; Gümrük, Fatma; Cetin, Mualla; Hiçsönmez, Gönül

    2005-01-01

    All-trans-retinoic acid (ATRA) has been shown to improve the outcome of patients with acute promyelocytic leukemia (APL). However, various adverse effects of ATRA treatment have been noted, such as scrotal and genital ulcers in adult patients. The authors report genital ulcers that developed in a child with APL after ATRA treatment. An 8-year-old girl with APL was treated with ATRA for 21 days and after discontinuation of ATRA treatment she developed genital ulcers. Systemic and local antibiotic pomades were applied and the lesions improved within 15 days. In conclusion, genital ulcers may develop in children with APL as a complication of ATRA treatment and physicians should be alert to this possibility.

  18. [Successful treatment of acute promyelocytic leukemia in a pregnant woman by using all-trans retinoic acid].

    Science.gov (United States)

    Tsuda, H; Doi, H; Inada, T; Shirono, K

    1994-07-01

    A 34-year-old woman was admitted because of pancytopenia with DIC in the 28th week of pregnancy. Bone marrow aspirate demonstrated 81.2% abnormal cells which showed Auer bodies and faggot formation. Chromosomal analysis demonstrated an abnormality, t (15; 17). The patient was diagnosed as having acute promyelocytic leukemia (APL) and started to receive treatment with all-trans retinoic acid (ATRA) 70 mg/body/day per os. She had a cesarean section and gave birth to a female infant in the 29th week of pregnancy. An increase of WBC counts was observed on the 9th hospital day, then chemotherapy with anti-cancer agents was performed additionally. Complete remission was achieved on the 27th hospital day. Management of pregnant patients with APL could be improved by using ATRA instead of conventional combinations of cytotoxic agents.

  19. [A neonate born to a mother with acute promyelocytic leukemia treated by all-trans retinoic acid].

    Science.gov (United States)

    Maeda, M; Tyugu, H; Okubo, T; Yamamoto, M; Nakamura, K; Dan, K

    1997-09-01

    We report a female neonate delivered in week 32 of gestation by a mother who had acute promyelocytic leukemia (APL) treated by all-trans retinoic acid (ATRA). APL was diagnosed in week 29 of gestation and was treated with ATRA from week 30. Physical examination and laboratory tests showed no abnormalities at birth. The girl has since shown normal development, with no peripheral blood abnormalities at 2 years old. Hypersegmented neutrophils, which often appear during ATRA treatment, were seen in the peripheral blood of the mother and cord blood but not peripheral blood of the neonate on the day of birth. ATRA is known to cross the placenta, and has been revealed to be teratogenic in animal studies. There have been eight neonates born to the mothers with APL who were treated with ATRA during pregnancy. All infants, including this one, have shown normal growth without any complications.

  20. All-trans retinoic acid enhances bystander effect of suicide gene therapy in the treatment of breast cancer.

    Science.gov (United States)

    Kong, Heng; Liu, Xia; Yang, Liucheng; Qi, Ke; Zhang, Haoyun; Zhang, Jingwen; Huang, Zonghai; Wang, Hongxian

    2016-03-01

    All-trans retinoic acid (ATRA) has been shown to enhance the expression of connexin 43 (Cx43) and the bystander effect (BSE) in suicide gene therapy. These in turn improve effects of suicide gene therapies for several tumor types. However, whether ATRA can improve BSE remains unclear in suicide gene therapy for breast cancer. In the present study, MCF-7, human breast cancer cells were treated with ATRA in combination with a VEGFP-TK/CD gene suicide system developed by our group. We found that this combination enhances the efficiency of cell killing and apoptosis of breast cancer by strengthening the BSE in vitro. ATRA also promotes gap junction intercellular communication (GJIC) in MCF-7 cells by upregulation of the connexin 43 mRNA and protein in MCF-7 cells. These results indicate that enhancement of GJIC by ATRA in suicide gene system might serve as an attractive and cost-effective strategy of therapy for breast cancer cells.

  1. All-trans retinoic acid increases oxidative metabolism in mature adipocytes

    DEFF Research Database (Denmark)

    Mercader, Josep; Madsen, Lise; Felipe, Francisco;

    2007-01-01

    BACKGROUND/AIMS: In rodents, retinoic acid (RA) treatment favors loss of body fat mass and the acquisition of brown fat features in white fat depots. In this work, we sought to examine to what extent these RA effects are cell autonomous or dependent on systemic factors. METHODS: Parameters of lipid...... metabolism and related gene expression were analyzed in differentiated 3T3-L1 adipocytes after exposure to RA or vehicle. RESULTS: Treatment with RA resulted in decreased cellular triacylglycerol content and increased basal lipolysis and fatty acid oxidation rate. At the mRNA level, RA treatment led......), and to an increased expression of proteins favoring fat oxidation (peroxisome proliferator-activated receptor gamma coactivator-1alpha, uncoupling protein 2, fasting-induced adipose factor, enzymes of mitochondrial fatty acid oxidation). These changes paralleled inactivation of the retinoblastoma protein and were...

  2. Knockdown of lecithin retinol acyltransferase increases all-trans retinoic acid levels and restores retinoid sensitivity in malignant melanoma cells.

    Science.gov (United States)

    Amann, Philipp M; Czaja, Katharina; Bazhin, Alexandr V; Rühl, Ralph; Skazik, Claudia; Heise, Ruth; Marquardt, Yvonne; Eichmüller, Stefan B; Merk, Hans F; Baron, Jens M

    2014-11-01

    Retinoids such as all-trans retinoic acid (ATRA) influence cell growth, differentiation and apoptosis and may play decisive roles in tumor development and progression. An essential retinoid-metabolizing enzyme known as lecithin retinol acyltransferase (LRAT) is expressed in melanoma cells but not in melanocytes catalysing the esterification of all-trans retinol (ATRol). In this study, we show that a stable LRAT knockdown (KD) in the human melanoma cell line SkMel23 leads to significantly increased levels of the substrate ATRol and biologically active ATRA. LRAT KD restored cellular sensitivity to retinoids analysed in cell culture assays and melanoma 3D skin models. Furthermore, ATRA-induced gene regulatory mechanisms drive depletion of added ATRol in LRAT KD cells. PCR analysis revealed a significant upregulation of retinoid-regulated genes such as CYP26A1 and STRA6 in LRAT KD cells, suggesting their possible involvement in mediating retinoid resistance in melanoma cells. In conclusion, LRAT seems to be important for melanoma progression. We propose that reduction in ATRol levels in melanoma cells by LRAT leads to a disturbance in cellular retinoid level. Balanced LRAT expression and activity may provide protection against melanoma development and progression. Pharmacological inhibition of LRAT activity could be a promising strategy for overcoming retinoid insensitivity in human melanoma cells.

  3. High albumin levels restrict the kinetics of 13-cis retinoic acid uptake and intracellular isomerization to all-trans retinoic acid and inhibit its anti-proliferative effect on SZ95 sebocytes.

    Science.gov (United States)

    Tsukada, Miki; Schröder, Mandy; Seltmann, Holger; Orfanos, Constantin E; Zouboulis, Christos C

    2002-07-01

    13-cis Retinoic acid is rapidly absorbed into cells and exerts its anti-proliferative effect on human sebocytes by specific isomerization to high levels of all-trans retinoic acid and binding the retinoic acid receptors. In this study, we have shown that bovine serum albumin, an extracellular binding protein for 13-cis retinoic acid, plays an important part in the uptake of 13-cis retinoic acid in human sebocytes, its intracellular isomerization to all-trans retinoic acid, and the induction of its anti-proliferative effect. The addition of highly concentrated bovine serum albumin (20 mg per ml) to the serum-free maintenance medium resulted in a rather controlled uptake of constant levels of 13-cis and all-trans retinoic acid into the cells over the 72 h of treatment. As a consequence, significantly reduced and delayed isomerization of 13-cis retinoic acid to all-trans retinoic acid was detected. In parallel experiments, the anti-proliferative activity of 13-cis retinoic acid on SZ95 sebocytes was abrogated by adding 20 mg bovine serum albumin per ml into the serum-free medium. These results indicate a critical function of serum albumin as retinoid-binding protein in reducing the concentration of active retinoids and restricting their biologic effects on human sebocytes.

  4. Retinoid X Receptor Agonists Upregulate Genes Responsible for the Biosynthesis of All-Trans-Retinoic Acid in Human Epidermis.

    Directory of Open Access Journals (Sweden)

    Lizhi Wu

    Full Text Available UAB30 is an RXR selective agonist that has been shown to have potential cancer chemopreventive properties. Due to high efficacy and low toxicity, it is currently being evaluated in human Phase I clinical trials by the National Cancer Institute. While UAB30 shows promise as a low toxicity chemopreventive drug, the mechanism of its action is not well understood. In this study, we investigated the effects of UAB30 on gene expression in human organotypic skin raft cultures and mouse epidermis. The results of this study indicate that treatment with UAB30 results in upregulation of genes responsible for the uptake and metabolism of all-trans-retinol to all-trans-retinoic acid (ATRA, the natural agonist of RAR nuclear receptors. Consistent with the increased expression of these genes, the steady-state levels of ATRA are elevated in human skin rafts. In ultraviolet B (UVB irradiated mouse skin, the expression of ATRA target genes is found to be reduced. A reduced expression of ATRA sensitive genes is also observed in epidermis of mouse models of UVB-induced squamous cell carcinoma and basal cell carcinomas. However, treatment of mouse skin with UAB30 prior to UVB irradiation prevents the UVB-induced decrease in expression of some of the ATRA-responsive genes. Considering its positive effects on ATRA signaling in the epidermis and its low toxicity, UAB30 could be used as a chemoprophylactic agent in the treatment of non-melanoma skin cancer, particularly in organ transplant recipients and other high risk populations.

  5. Retinoid X Receptor Agonists Upregulate Genes Responsible for the Biosynthesis of All-Trans-Retinoic Acid in Human Epidermis.

    Science.gov (United States)

    Wu, Lizhi; Chaudhary, Sandeep C; Atigadda, Venkatram R; Belyaeva, Olga V; Harville, Steven R; Elmets, Craig A; Muccio, Donald D; Athar, Mohammad; Kedishvili, Natalia Y

    2016-01-01

    UAB30 is an RXR selective agonist that has been shown to have potential cancer chemopreventive properties. Due to high efficacy and low toxicity, it is currently being evaluated in human Phase I clinical trials by the National Cancer Institute. While UAB30 shows promise as a low toxicity chemopreventive drug, the mechanism of its action is not well understood. In this study, we investigated the effects of UAB30 on gene expression in human organotypic skin raft cultures and mouse epidermis. The results of this study indicate that treatment with UAB30 results in upregulation of genes responsible for the uptake and metabolism of all-trans-retinol to all-trans-retinoic acid (ATRA), the natural agonist of RAR nuclear receptors. Consistent with the increased expression of these genes, the steady-state levels of ATRA are elevated in human skin rafts. In ultraviolet B (UVB) irradiated mouse skin, the expression of ATRA target genes is found to be reduced. A reduced expression of ATRA sensitive genes is also observed in epidermis of mouse models of UVB-induced squamous cell carcinoma and basal cell carcinomas. However, treatment of mouse skin with UAB30 prior to UVB irradiation prevents the UVB-induced decrease in expression of some of the ATRA-responsive genes. Considering its positive effects on ATRA signaling in the epidermis and its low toxicity, UAB30 could be used as a chemoprophylactic agent in the treatment of non-melanoma skin cancer, particularly in organ transplant recipients and other high risk populations.

  6. Clinical significance of CD56 expression in patients with acute promyelocytic leukemia treated with all-trans retinoic acid and anthracycline-based regimens

    NARCIS (Netherlands)

    Montesinos, Pau; Rayon, Chelo; Vellenga, Edo; Brunet, Salut; Gonzalez, Jose; Gonzalez, Marcos; Holowiecka, Aleksandra; Esteve, Jordi; Bergua, Juan; Gonzalez, Jose D.; Rivas, Concha; Tormo, Mar; Rubio, Vicente; Bueno, Javier; Manso, Felix; Milone, Gustavo; de la Serna, Javier; Perez, Inmaculada; Perez-Encinas, Manuel; Krsnik, Isabel; Ribera, Josep M.; Escoda, Lourdes; Lowenberg, Bob; Sanz, Miguel A.

    2011-01-01

    The expression of CD56 antigen in acute promyelocytic leukemia (APL) blasts has been associated with short remission duration and extramedullary relapse. We investigated the clinical significance of CD56 expression in a large series of patients with APL treated with all-trans retinoic acid and anthr

  7. Prognostic value of FLT3 mutations in patients with acute promyelocytic leukemia treated with all-trans retinoic acid and anthracycline monochemotherapy

    NARCIS (Netherlands)

    Barragan, Eva; Montesinos, Pau; Camos, Mireia; Gonzalez, Marcos; Calasanz, Maria J.; Roman-Gomez, Jose; Gomez-Casares, Maria T.; Ayala, Rosa; Lopez, Javier; Fuster, Oscar; Colomer, Dolors; Chillon, Carmen; Larrayoz, Maria J.; Sanchez-Godoy, Pedro; Gonzalez-Campos, Jose; Manso, Felix; Amador, Maria L.; Vellenga, Edo; Lowenberg, Bob; Sanz, Miguel A.

    2011-01-01

    Background Fms-like tyrosine kinase-3 (FLT3) gene mutations are frequent in acute promyelocytic leukemia but their prognostic value is not well established. Design and Methods We evaluated FLT3-internal tandem duplication and FLT3-D835 mutations in patients treated with all-trans retinoic acid and a

  8. Contrasting Roles For All-Trans Retinoic Acid in TGF-ß-mediated Induction of Foxp3 and Il10 Genes in Developing Regulatory T Cells

    Science.gov (United States)

    Extrathymic induction of regulatory T cells (Treg) is essential to the regulation of effector T cell responses in the periphery. TGF-ß has been shown to induce Foxp3-expressing Tregs both in vitro and in vivo. More recently, the vitamin A metabolite, all-trans retinoic acid (at-RA), has been found t...

  9. Differentiation syndrome in patients with acute promyelocytic leukemia treated with all- trans retinoic acid and anthracycline chemotherapy: Characteristics, outcome, and prognostic factors

    NARCIS (Netherlands)

    P. Montesinos (Pau); J.M. Bergua (Juan Miguel); E. Vellenga (Edo); C. Rayón (Chelo); R. Parody (Ricardo); J. de Serna (Javier); A. León (Angel); J. Esteve (Jordi); G. Milone (Gustavo); G. Debén (Guillermo); C. Rivas (Concha); M. González (Marcos); M. Tormo (Mar); D.M. Joaquín; J.D. González (José David); S. Negri (Silvia); E. Amutio (Elena); S. Brunet (Salut); B. Löwenberg (Bob); M.A. Sanz (Miguel Angel)

    2009-01-01

    textabstractDifferentiation syndrome (DS) can be a life-threatening complication in patients with acute promyelocytic leukemia (APL) undergoing induction therapy with all- trans retinoic acid (ATRA). Detailed knowl- edge about DS has remained limited. We present an analysis of the incidence, char- a

  10. Treatment of newly diagnosed and relapsed acute promyelocytic leukemia with intravenous liposomal all-trans retinoic acid.

    Science.gov (United States)

    Douer, D; Estey, E; Santillana, S; Bennett, J M; Lopez-Bernstein, G; Boehm, K; Williams, T

    2001-01-01

    A novel intravenous liposomal formulation of all-trans retinoic acid (ATRA) was evaluated in 69 patients with acute promyelocytic leukemia (APL): 32 new diagnoses, 35 relapses, and 2 oral ATRA failures. Liposomal ATRA (90 mg/m(2)) was administered every other day until complete remission (CR) or a maximum of 56 days. Treatment following CR was liposomal ATRA with or without chemotherapy. In an intent-to-treat (ITT) analysis of all patients, CR rates were 62%, 70%, and 20% in newly diagnosed, group 1 first relapses (ATRA naive or off oral ATRA more than or equal to 1 year), or group 2 relapses (second or subsequent relapse or first relapses off oral ATRA less than 1 year), respectively. In 56 evaluable patients (receiving 4 or more doses), CR rates for the same groups were 87% (20 of 23), 78% (14 of 18), and 23% (3 of 13). Remission failure in newly diagnosed patients was not from resistant disease. Several patients in CR became polymerase chain reaction (PCR) negative for promyelocytic leukemia/retinoic acid receptor-alpha (PML/RARalpha) after liposomal ATRA alone. Toxicity was generally mild, most commonly headaches (67. 5%). Eighteen patients (26%) had ATRA syndrome develop during induction. One-year survival of ITT patients was 62%, 56%, and 20% for newly diagnosed, group 1, and group 2, respectively. The medium duration of CR has not yet been reached and was 18 and 5.5 months in the same groups. These results demonstrate that liposomal ATRA is effective in inducing CR in newly diagnosed or group 1 APL patients. It provides a reliable dosage of ATRA for patients with APL unable to swallow or absorb medications and can induce molecular remissions without chemotherapy.

  11. Effect of all-trans retinoic acid 0n drug sensitivity and expression of survivin in LoVo cells

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Background All-trans retinoic acid(ATRA)can influence the tumor cell proliferation cycle,and some chemotherapeutic drugs are cycle specific.In this study,we hypothesize that ATRA can enhance chemotherapeutic drug sensitivity by affecting the cell cycle of tumor cells.Methods The cell cycle of LoVo cells was evaluated using flow cytometry(FCM).Cell viability was analyzed using the MTT assay.The morphologic changes in the treated LoVo cells were measured with acridine orange (AO)/ethidium bromide(EB)staining.Expression of survivin in LoVo cells was analyzed by immunofluorescence assay.Results After LoVo cells were treated with ATRA,the G0/G1 ratio of the tumor cells increased and the cell ratio of Sand G2/M-phase decreased.Viability of the cells decreased significantly after combined treatment with ATRA and 5-fluorouracil(5-FU)or mitomycin c(MMC) and was evaluated by fluorescence microscopy.Expression level of survivin in the tumor cells decreased after ATRA combination treatment.Conclusions ATRA enhances drug sensitivity of the LoVo cell line to cell cycle-specific agents and inhibits the expression of survivin in LoVo cells.The combination of ATRA and 5-FU or MMC promoted cell apoptosis,and the mechanism involved in apoptosis may be related to inhibition of survivin gene expression.

  12. [Acute promyelocytic leukemia (APL) resulting in broad cerebral infarction during all-trans retinoic acid (ATRA) treatment].

    Science.gov (United States)

    Ikeda, Y; Yoshinaga, K; Iki, S; Ohbayashi, Y; Urabe, A

    1994-02-01

    A 27-year-old woman visited Kanto Teishin Hospital complaining of fever and petechiae in September, 1992. Her fetus had suddenly died in the uterus two weeks before (in the sixth month of pregnancy). Total white blood cell (WBC) count was 3.2 x 10(3)/microliters with 80% promyelocytes. Bone marrow was hypercellular with 90% promyelocytes. Disseminated intravascular coagulation (DIC) was recognized. She was diagnosed as having acute promyelocytic leukemia (APL), and treatment with daily oral administration of all-trans retinoic acid (ATRA) (70 mg/body/day) was begun. On day 4, hemiplegia and aphasia appeared. Broad cerebral infarction was suspected from computed tomography. On day 9, the WBC count increased rapidly, standard chemotherapy was added and she achieved complete remission. ATRA is known to have stimulatory effects on the differentiation of APL cells, but some reports have described thromboembolic events during the administration of ATRA. In this case, ATRA might have affected coagulability resulting in cerebral infarction.

  13. Isocitrate dehydrogenase 1 mutations prime the all-trans retinoic acid myeloid differentiation pathway in acute myeloid leukemia.

    Science.gov (United States)

    Boutzen, Héléna; Saland, Estelle; Larrue, Clément; de Toni, Fabienne; Gales, Lara; Castelli, Florence A; Cathebas, Mathilde; Zaghdoudi, Sonia; Stuani, Lucille; Kaoma, Tony; Riscal, Romain; Yang, Guangli; Hirsch, Pierre; David, Marion; De Mas-Mansat, Véronique; Delabesse, Eric; Vallar, Laurent; Delhommeau, François; Jouanin, Isabelle; Ouerfelli, Ouathek; Le Cam, Laurent; Linares, Laetitia K; Junot, Christophe; Portais, Jean-Charles; Vergez, François; Récher, Christian; Sarry, Jean-Emmanuel

    2016-04-04

    Acute myeloid leukemia (AML) is characterized by the accumulation of malignant blasts with impaired differentiation programs caused by recurrent mutations, such as the isocitrate dehydrogenase (IDH) mutations found in 15% of AML patients. These mutations result in the production of the oncometabolite (R)-2-hydroxyglutarate (2-HG), leading to a hypermethylation phenotype that dysregulates hematopoietic differentiation. In this study, we identified mutant R132H IDH1-specific gene signatures regulated by key transcription factors, particularly CEBPα, involved in myeloid differentiation and retinoid responsiveness. We show that treatment with all-trans retinoic acid (ATRA) at clinically achievable doses markedly enhanced terminal granulocytic differentiation in AML cell lines, primary patient samples, and a xenograft mouse model carrying mutant IDH1. Moreover, treatment with a cell-permeable form of 2-HG sensitized wild-type IDH1 AML cells to ATRA-induced myeloid differentiation, whereas inhibition of 2-HG production significantly reduced ATRA effects in mutant IDH1 cells. ATRA treatment specifically decreased cell viability and induced apoptosis of mutant IDH1 blasts in vitro. ATRA also reduced tumor burden of mutant IDH1 AML cells xenografted in NOD-Scid-IL2rγ(null)mice and markedly increased overall survival, revealing a potent antileukemic effect of ATRA in the presence of IDH1 mutation. This therapeutic strategy holds promise for this AML patient subgroup in future clinical studies.

  14. All-trans-Retinoic Acid Ameliorated High Fat Diet-Induced Atherosclerosis in Rabbits by Inhibiting Platelet Activation and Inflammation

    Directory of Open Access Journals (Sweden)

    Birong Zhou

    2012-01-01

    Full Text Available Background. All-trans-retinoic acid (atRA is effective for many proliferative diseases. We investigated the protective effects of atRA against atherosclerosis. Methods. Rabbits were randomly allocated to receive basal diet or an HFD for 4 weeks. HFD group then received rosuvastatin (3 mg/day, atRA (5 mg/kg/day, or the same volume of vehicle, respectively, for next 8 weeks. Results. HFD group showed increases in plasma lipids and aortic plaque formation. P-selectin expression and fibrinogen binding on platelets or deposition on the intima of the aorta also increased significantly as did the levels of TNF-α, IL-6, and fibrinogen in plasma. After 8 weeks of treatment with atRA, there was a significant decrease in plasma lipids and improvement in aortic lesions. AtRA also inhibited the expression of P-selectin and fibrinogen binding on platelets and deposition on the intima of the aorta. Conclusion. AtRA can ameliorate HFD-induced AS in rabbits by inhibiting platelet activation and inflammation.

  15. Improved Homology Model of the Human all-trans Retinoic Acid Metabolizing Enzyme CYP26A1

    Directory of Open Access Journals (Sweden)

    Mohamed K. A. Awadalla

    2016-03-01

    Full Text Available A new CYP26A1 homology model was built based on the crystal structure of cyanobacterial CYP120A1. The model quality was examined for stereochemical accuracy, folding reliability, and absolute quality using a variety of different bioinformatics tools. Furthermore, the docking capabilities of the model were assessed by docking of the natural substrate all-trans-retinoic acid (atRA, and a group of known azole- and tetralone-based CYP26A1 inhibitors. The preferred binding pose of atRA suggests the (4S-OH-atRA metabolite production, in agreement with recently available experimental data. The distances between the ligands and the heme group iron of the enzyme are in agreement with corresponding distances obtained for substrates and azole inhibitors for other cytochrome systems. The calculated theoretical binding energies agree with recently reported experimental data and show that the model is capable of discriminating between natural substrate, strong inhibitors (R116010 and R115866, and weak inhibitors (liarozole, fluconazole, tetralone derivatives.

  16. All-trans retinoic acid promotes neural lineage entry by pluripotent embryonic stem cells via multiple pathways

    Directory of Open Access Journals (Sweden)

    Fang Bo

    2009-07-01

    Full Text Available Abstract Background All-trans retinoic acid (RA is one of the most important morphogens with pleiotropic actions. Its embryonic distribution correlates with neural differentiation in the developing central nervous system. To explore the precise effects of RA on neural differentiation of mouse embryonic stem cells (ESCs, we detected expression of RA nuclear receptors and RA-metabolizing enzymes in mouse ESCs and investigated the roles of RA in adherent monolayer culture. Results Upon addition of RA, cell differentiation was directed rapidly and exclusively into the neural lineage. Conversely, pharmacological interference with RA signaling suppressed this neural differentiation. Inhibition of fibroblast growth factor (FGF signaling did not suppress significantly neural differentiation in RA-treated cultures. Pharmacological interference with extracellular signal-regulated kinase (ERK pathway or activation of Wnt pathway effectively blocked the RA-promoted neural specification. ERK phosphorylation was enhanced in RA-treated cultures at the early stage of differentiation. Conclusion RA can promote neural lineage entry by ESCs in adherent monolayer culture systems. This effect depends on RA signaling and its crosstalk with the ERK and Wnt pathways.

  17. Polymeric nanoparticles based on chitooligosaccharide as drug carriers for co-delivery of all-trans-retinoic acid and paclitaxel.

    Science.gov (United States)

    Zhang, Jing; Han, Jian; Zhang, Xiuli; Jiang, Jing; Xu, Maolei; Zhang, Daolai; Han, Jingtian

    2015-09-20

    An amphiphilic all-trans-retinoic acid (ATRA)-chitooligosaccharide (RCOS) conjugate was synthesized to form self-assembled polymeric nanoparticles to facilitate the co-delivery of ATRA and paclitaxel (PTX). The blank RCOS nanoparticles possessed low hemolytic activity and cytotoxicity, and could efficiently load PTX with a drug loading of 22.2% and a high encapsulation efficiency of 71.3%. PTX-loaded RCOS nanoparticles displayed a higher cytotoxicity to HepG2 cells compared to PTX plus ATRA solution when corrected by the accumulated drug release. Cellular uptake profiles of RCOS nanoparticles were evaluated via confocal laser scanning microscope and flow cytometry with FITC as a fluorescent mark. The RCOS nanoparticles could be rapidly and continuously taken up by HepG2 cells via endocytosis and transported into the nucleus, and the uptake rates increased with particle concentration. These results revealed the promising potential of RCOS nanoparticles as drug carriers for co-delivery of ATRA and PTX or other hydrophobic therapeutic agents.

  18. The Expression of Bone Morphogenetic Protein 2 and Matrix Metalloproteinase 2 through Retinoic Acid Receptor Beta Induced by All-Trans Retinoic Acid in Cultured ARPE-19 Cells.

    Directory of Open Access Journals (Sweden)

    Zhenya Gao

    Full Text Available All-trans retinoic acid (ATRA plays an important role in ocular development. Previous studies found that retinoic acid could influence the metabolism of scleral remodeling by promoting retinal pigment epithelium (RPE cells to secrete secondary signaling factors. The purpose of this study was to investigate whether retinoic acid affected secretion of bone morphogenetic protein 2 (BMP-2 and matrix metalloproteinase 2 (MMP-2 and to explore the signaling pathway of retinoic acid in cultured acute retinal pigment epithelial 19 (ARPE-19 cells.The effects of ATRA (concentrations from 10-9 to 10-5 mol/l on the expression of retinoic acid receptors (RARs in ARPE-19 cells were examined at the mRNA and protein levels using reverse transcription-polymerase chain reaction (RT-PCR and western blot assay, respectively. The effects of treating ARPE-19 cells with ATRA concentrations ranging from 10-9 to 10-5 mol/l for 24 h and 48 h or with 10-6mol/l ATRA at different times ranging from 6h to 72h were assessed using real-time quantitative PCR (qPCR and enzyme-linked immunosorbent assay (ELISA. The contribution of RARβ-induced activation of ARPE-19 cells was confirmed using LE135, an antagonist of RARβ.RARβ mRNA levels significantly increased in the ARPE-19 cells treated with ATRA for 24h and 48h. These increases in RARβ mRNA levels were dose dependent (at concentrations of 10-9 to 10-5 mol/l with a maximum effect observed at 10-6 mol/l. There were no significant changes in the mRNA levels of RARα and RARγ. Western blot assay revealed that RARβ protein levels were increased significantly in a time-dependent manner in ARPE-19 cells treated with 10-6 mol/l ATRA from 12 h to 72 h, with a marked increase observed at 24 h and 48 h. The upregulation of RARβ and the ATRA-induced secretion in ARPE-19 cells could be inhibited by the RARβ antagonist LE135.ATRA induced upregulation of RARβ in ARPE-19 cells and stimulated these cells to secrete BMP-2 and MMP-2.

  19. Effects of receptor-selective retinoids on CYP26 gene expression and metabolism of all-trans-retinoic acid in intestinal cells.

    Science.gov (United States)

    Lampen, A; Meyer, S; Nau, H

    2001-05-01

    Retinoids mediate most of their function via interaction with retinoid receptors [retinoic acid receptors (RARs) and retinoid X receptors (RXRs)], which act as ligand-activated transcription factors controlling the expression of a number of target genes. The complex mechanistic pattern of retinoid-induced effects on gene expression of CYP26 and intestinal metabolism of all-trans-retinoic acid (RA) was investigated here by studying the effects of retinoid ligands with relative selectivity for binding and transactivation of the retinoid acid receptors, RARs and RXRs, in human intestinal Caco-2 cells. We show here that CYP26 is expressed in human duodenum and colon. In Caco-2 cells not only all-trans-RA but also synthetic agonists of the RAR induced intestinal CYP26 gene expression and all-trans-RA metabolism as well. The RARalpha ligand Am580 induced the CYP26 gene expression more than the RARbeta ligand CD2019 or the RARgamma ligand CD437 suggesting the highest specificity for RARalpha on intestinal CYP26 gene regulation. RXR ligands alone did not induce CYP26 gene expression or RA metabolism in Caco-2 cells at all. But together with the RARalpha ligand, Am580, there were enhanced effects on the induction of CYP26 gene expression and on the induction of the metabolism of all-trans-RA. We conclude that gene regulation of CYP26 and the metabolism of all-trans-RA in intestinal cells is regulated through RXR and RAR heterodimerization. When coadministered, RAR agonists showed the highest potency for CYP26 gene regulation. Receptor-selective retinoids showed enhanced effects on induction of CYP26 gene expression and all-trans-retinoic acid metabolism.

  20. Cancer procoagulant and tissue factor are differently modulated by all-trans-retinoic acid in acute promyelocytic leukemia cells.

    Science.gov (United States)

    Falanga, A; Consonni, R; Marchetti, M; Locatelli, G; Garattini, E; Passerini, C G; Gordon, S G; Barbui, T

    1998-07-01

    All-trans-retinoic acid (ATRA) downregulates the expression of two cellular procoagulants, tissue factor (TF) and cancer procoagulant (CP), in human promyelocytic leukemia cells. To evaluate whether or not changes of the procoagulant activities (PCAs) may share mechanisms with the ATRA-induced cyto-differentiation process, we have characterized the effect of ATRA on the TF and CP expression by NB4 cells, an ATRA maturation-inducible cell line, and two NB4-derived cell lines resistant to ATRA-induced maturation, the NB4. 306 and NB4.007/6 cells. Next, we evaluated the effect on the PCAs of the NB4 parental cells of three synthetic retinoid analogues, ie: AM580 (selective for the retinoic acid receptor [RAR] alpha), capable to induce the granulocytic differentiation of NB4 cells; and CD2019 (selective for RARbeta) and CD437 (selective for RARgamma), both lacking this capability. Cells were treated with either ATRA or the analogues (10(-6) to 10(-8) mol/L) for 96 hours. The effect on cell differentiation was evaluated by morphologic changes, cell proliferation, nitro blue tetrazolium reduction assay, and flow cytometry analysis of the CD33 and CD11b surface-antigen expression. PCA was first measured in 20 mmol/L Veronal Buffer cell extracts by the one-stage clotting assay of normal and FVII-deficient plasmas. Further TF and CP have been characterized and quantified in cell-sample preparations by chromogenic and immunological assays. In the first series of experiments, ATRA downregulates both TF and CP in NB4 parental cells, as expected. However, in the differentiation-resistant cell lines, it induced a significant loss of TF but had little or no effect on CP. In a second series of experiments, in the NB4 parental cells, the RARalpha agonist (AM580) induced cell maturation and reduced 91% CP expression, whereas CD437 and CD2019 had no cyto-differentiating effects and did not affect CP levels. On the other hand, in the same cells the TF expression was reduced by ATRA

  1. Long-term outcome of acute promyelocytic leukemia treated with all-trans-retinoic acid, arsenic trioxide, and gemtuzumab.

    Science.gov (United States)

    Abaza, Yasmin; Kantarjian, Hagop; Garcia-Manero, Guillermo; Estey, Elihu; Borthakur, Gautam; Jabbour, Elias; Faderl, Stefan; O'Brien, Susan; Wierda, William; Pierce, Sherry; Brandt, Mark; McCue, Deborah; Luthra, Rajyalakshmi; Patel, Keyur; Kornblau, Steven; Kadia, Tapan; Daver, Naval; DiNardo, Courtney; Jain, Nitin; Verstovsek, Srdan; Ferrajoli, Alessandra; Andreeff, Michael; Konopleva, Marina; Estrov, Zeev; Foudray, Maria; McCue, David; Cortes, Jorge; Ravandi, Farhad

    2017-03-09

    The combination of all-trans-retinoic acid (ATRA) plus arsenic trioxide (ATO) has been shown to be superior to ATRA plus chemotherapy in the treatment of standard-risk patients with newly diagnosed acute promyelocytic leukemia (APL). A recent study demonstrated the efficacy of this regimen with added gemtuzumab ozogamicin (GO) in high-risk patients. We examined the long-term outcome of patients with newly diagnosed APL treated at our institution on 3 consecutive prospective clinical trials, using the combination of ATRA and ATO, with or without GO. For induction, all patients received ATRA (45 mg/m(2) daily) and ATO (0.15 mg/kg daily) with a dose of GO (9 mg/m(2) on day 1) added to high-risk patients (white blood cell count, >10 × 10(9)/L), as well as low-risk patients who experienced leukocytosis during induction. Once in complete remission, patients received 4 cycles of ATRA plus ATO consolidation. One hundred eighty-seven patients, including 54 with high-risk and 133 with low-risk disease, have been treated. The complete remission rate was 96% (52 of 54 in high-risk and 127 of 133 in low-risk patients). Induction mortality was 4%, with only 7 relapses. Among low-risk patients, 60 patients (45%) required either GO or idarubicin for leukocytosis. Median duration of follow-up was 47.6 months. The 5-year event-free, disease-free, and overall survival rates are 85%, 96%, and 88%, respectively. Late hematological relapses beyond 1 year occurred in 3 patients. Fourteen deaths occurred beyond 1 year; 12 were related to other causes. This study confirms the durability of responses with this regimen.

  2. Aerosol probes of emphysema progression in dogs treated with all trans retinoic acid--an exploratory study.

    Science.gov (United States)

    Rosenthal, Frank S

    2007-01-01

    This study used aerosol probes and lung function tests to investigate whether all trans retinoic acid (RA) can reverse experimental emphysema in dogs. Three dogs were evaluated with lung mechanics tests, including inspiratory capacity (IC), total lung capacity (TLC), and the ratio of forced expired volume in 0.5 sec to forced vital capacity (FEV0.5/FVC), an aerosol-derived measure of pulmonary airspace size (effective airspace diameter, EAD), and an aerosol-derived measure of nonuniform ventilation (aerosol dispersion, AD). Emphysema was induced by exposure to aerosolized papain. At 11 or 12 weeks post-papain exposure, dogs received oral RA (2 mg/kg/day) for 8 weeks, and were followed for an additional 4 weeks after stopping RA treatment. In all dogs, lung injury increased in the first 11-12 weeks following papain exposure, as evidenced by increasing trends of inspiratory capacity IC, TLC, EAD, and AD, and a decreasing trend of FEV0.5/FVC. These parameters of lung injury partially and transiently reversed their trends between 2 and 6 weeks following the initiation of RA treatment. A sham RA-treated group was not studied. However, similar reversals of lung injury were not seen in a previous study of dogs treated with papain but not RA, suggesting that RA altered emphysema progression in the current study. The limited reversal of lung injury in this study contrasts with more pronounced treatment effects seen in previous studies with rats. This paper discusses possible reasons for differences in these studies, as well as suggestions for improved experimental investigations of emphysema therapies.

  3. All-trans retinoic acid-triggered antimicrobial activity against Mycobacterium tuberculosis is dependent on NPC2.

    Science.gov (United States)

    Wheelwright, Matthew; Kim, Elliot W; Inkeles, Megan S; De Leon, Avelino; Pellegrini, Matteo; Krutzik, Stephan R; Liu, Philip T

    2014-03-01

    A role for vitamin A in host defense against Mycobacterium tuberculosis has been suggested through epidemiological and in vitro studies; however, the mechanism is unclear. In this study, we demonstrate that vitamin A-triggered antimicrobial activity against M. tuberculosis requires expression of NPC2. Comparison of monocytes stimulated with all-trans retinoic acid (ATRA) or 1,25-dihydroxyvitamin D3 (1,25D3), the biologically active forms of vitamin A and vitamin D, respectively, indicates that ATRA and 1,25D3 induce mechanistically distinct antimicrobial activities. Stimulation of primary human monocytes with ATRA did not result in expression of the antimicrobial peptide cathelicidin, which is required for 1,25D3 antimicrobial activity. In contrast, ATRA triggered a reduction in the total cellular cholesterol concentration, whereas 1,25D3 did not. Blocking ATRA-induced cellular cholesterol reduction inhibits antimicrobial activity as well. Bioinformatic analysis of ATRA- and 1,25D3-induced gene profiles suggests that NPC2 is a key gene in ATRA-induced cholesterol regulation. Knockdown experiments demonstrate that ATRA-mediated decrease in total cellular cholesterol content and increase in lysosomal acidification are both dependent upon expression of NPC2. Expression of NPC2 was lower in caseous tuberculosis granulomas and M. tuberculosis-infected monocytes compared with normal lung and uninfected cells, respectively. Loss of NPC2 expression ablated ATRA-induced antimicrobial activity. Taken together, these results suggest that the vitamin A-mediated antimicrobial mechanism against M. tuberculosis requires NPC2-dependent expression and function, indicating a key role for cellular cholesterol regulation in the innate immune response.

  4. Paradoxical effects of all-trans-retinoic acid on lupus-like disease in the MRL/lpr mouse model.

    Directory of Open Access Journals (Sweden)

    Xiaofeng Liao

    Full Text Available Roles of all-trans-retinoic acid (tRA, a metabolite of vitamin A (VA, in both tolerogenic and immunogenic responses are documented. However, how tRA affects the development of systemic autoimmunity is poorly understood. Here we demonstrate that tRA have paradoxical effects on the development of autoimmune lupus in the MRL/lpr mouse model. We administered, orally, tRA or VA mixed with 10% of tRA (referred to as VARA to female mice starting from 6 weeks of age. At this age, the mice do not exhibit overt clinical signs of lupus. However, the immunogenic environment preceding disease onset has been established as evidenced by an increase of total IgM/IgG in the plasma and expansion of lymphocytes and dendritic cells in secondary lymphoid organs. After 8 weeks of tRA, but not VARA treatment, significantly higher pathological scores in the skin, brain and lung were observed. These were accompanied by a marked increase in B-cell responses that included autoantibody production and enhanced expression of plasma cell-promoting cytokines. Paradoxically, the number of lymphocytes in the mesenteric lymph node decreased with tRA that led to significantly reduced lymphadenopathy. In addition, tRA differentially affected renal pathology, increasing leukocyte infiltration of renal tubulointerstitium while restoring the size of glomeruli in the kidney cortex. In contrast, minimal induction of inflammation with tRA in the absence of an immunogenic environment in the control mice was observed. Altogether, our results suggest that under a predisposed immunogenic environment in autoimmune lupus, tRA may decrease inflammation in some organs while generating more severe disease in others.

  5. Effect of all-trans retinoic acid on newly diagnosed acute promyelocytic leukemia patients: results of a Brazilian center

    Directory of Open Access Journals (Sweden)

    B.C. de-Medeiros

    1998-12-01

    Full Text Available Thirty-seven patients with acute promyelocytic leukemia (APL were treated with all-trans retinoic acid (ATRA. Patients received 45 mg m-2 day-1 po of ATRA until complete remission (CR was achieved, defined as: a presence of less than 5% blasts in the bone marrow, with b white blood cells >103/mm3, c platelets >105/mm3 and d hemoglobin concentration >8 g/dl, with no blood or platelet transfusions. Thirty-one (83.7% patients achieved CR by day 50, and 75% of these before day 30. Correction of the coagulopathy, achieved between days 2 and 10 (mean, 3 days, was the first evidence of response to treatment. Only one patient had been previously treated with chemotherapy and three had the microgranular variant M3 form. Dryness of skin and mucosae was the most common side effect observed in 82% of the patients. Thrombosis, hepatotoxicity and retinoid acid syndrome (RAS were observed in 7 (19%, 6 (16% and 4 (11% patients, respectively. Thirteen (35% patients had to be submitted to chemotherapy due to hyperleukocytosis (above 40 x 103/mm3 and six of these presented with new signs of coagulopathy after chemotherapy. Four (11% patients died secondarily to intracerebral hemorrhage (IH and two (5.4% dropped out of the protocol due to severe ATRA side effects (one RAS and one hepatotoxicity. RAS and IH were related strictly to hyperleukocytosis. The reduced use of platelets and fresh frozen plasma probably lowered the total cost of treatment. We conclude that ATRA is an effective agent for inducing complete remission in APL patients.

  6. All-trans retinoic acid prevents epidural fibrosis through NF-κB signaling pathway in post-laminectomy rats.

    Science.gov (United States)

    Zhang, Chao; Kong, Xiaohong; Ning, Guangzhi; Liang, Zhipin; Qu, Tongjun; Chen, Feiran; Cao, Daigui; Wang, Tianyi; Sharma, Hari S; Feng, Shiqing

    2014-04-01

    Laminectomy is a widely accepted treatment for lumbar disorders, and epidural fibrosis (EF) is a common complication. EF is thought to cause post-operative pain recurrence after laminectomy or discectomy. All-trans retinoic acid (ATRA) has shown anti-fibrotic, anti-inflammatory, and anti-proliferative functions. The object of this study was to investigate the effects of ATRA on the prevention of EF in post-laminectomy rats. In vitro, the anti-fibrotic effect of ATRA was demonstrated with cultured fibroblasts count, which comprised of those that were cultured with/without ATRA. In vivo, rats underwent laminectomy at the L1-L2 levels. We first demonstrated the beneficial effects using 0.05% ATRA compared to vehicle (control group). We found that a higher concentration of ATRA (0.1%) achieved dose-dependent results. Hydroxyproline content, Rydell score, vimentin-positive cell density, fibroblast density, inflammatory cell density and inflammatory factor expression levels all suggested better outcomes in the 0.1% ATRA rats compared to the other three groups. Presumably, these effects involved ATRA's ability to suppress transforming growth factor (TGF-β1) and interleukin (IL)-6 which was confirmed with reverse-transcriptase polymerase chain reaction (RT-PCR). Finally we demonstrated that ATRA down-regulated nuclear factor (NF)-κB by immunohistochemistry and western blotting for p65 and inhibition of κB (IκBα), respectively. Our findings indicate that topical application of ATRA can inhibit fibroblast proliferation, decrease TGF-β1 and IL-6 expression level, and prevent epidural scar adhesion in rats. The highest concentration employed in this study (0.1%) was the most effective. ATRA suppressed EF through down-regulating NF-κB signaling, whose specific mechanism is suppression of IκB phosphorylation and proteolytic degradation.

  7. Combination of arsenicum trioxide and all trans retinoic acid in the treatment of relapsed acute promyelocytic leukemia

    Directory of Open Access Journals (Sweden)

    A. N. Sokolov

    2015-01-01

    Full Text Available From 2001 to 2013 eleven patients with relapsed acute promyelocytic leukemia (APL (median age – 30 years received arsenicum trioxide (ATO. ATO was administered as a 2nd line relapse therapy in 9 patients, as 1st line relapse therapy in 2 patients. ATO was administered in a dose of 0.1 mg/kg in 7 patients, 0.15 mg/kg – in 4 patients. The induction duration was 14 days in 3 patients, 24–35 days in 2 patients, 60 days in 6 patients. From the 1st day of ATO patients received 45 mg/m2 all trans retinoic acid (ATRA (1 patient – from day 29 of ATO therapy. Maintenance therapy ATO + ATRA (10–14 days courses, every four weeks patients were receiving during 10–15 months. 2 from 3 patients with molecular relapses achieved remission lasting 57 and 89 months after the 14-day ATO courses. 1 from 2 patients with bone marrow relapse achieved remission lasting 27 months after the 24–35-day ATO courses. 60-day courses were effective in 5 of 6 patients: in 4 of which remission are retained during 16, 19, 27, 57 months; 1 patient was relapsed after 12 months; 1 patient did not achieve molecular remission. 3 patients received allogeneic hematopoietic stem cell transplantation (alloHSCT, 2 of which alive in remission. 1 patient received autologous hematopoietic stem cell transplantation in the 2nd molecular remission (alive in remission. 4 patients died: 1 – in the 3rd relapse (duration of 2nd remission – 9 months, 1 – in remission from complications after alloHSCT, 1 – from APL progression, 1 – sudden death in 2nd remission lasting 72 months. ATO + ATRA for 60 days with supportive therapy are more effective than chemotherapy in the treatment of APL relapse. Interferon α + ATRA are inappropriate treatment of APL molecular and cytogenetic relapse. Using autologous HSCT in 2nd molecular remission will improve the results of APL relapse treatment.

  8. Inhalation administration of all-trans-retinoic acid for treatment of elastase-induced pulmonary emphysema in Fischer 344 rats.

    Science.gov (United States)

    March, Thomas H; Cossey, Patricia Y; Esparza, Dolores C; Dix, Kelly J; McDonald, Jacob D; Bowen, Larry E

    2004-01-01

    A past study demonstrated that all-trans-retinoic acid (ATRA) treatment by intraperitoneal injection in a rat model of elastase-induced emphysema caused tissue regeneration as evidenced by a decrease in alveolar size and lung volume and an increase in alveolar number. We postulated that treatment with this retinoid by nose-only inhalation exposure would be a more efficient means of targeting damaged lung tissue. Emphysema was induced in male Fischer 344 rats by intratracheal instillation of pancreatic elastase (0.5 IU/g body weight). Four weeks after elastase instillation, animals were treated once daily, 4 days/week, for 3 weeks by exposing them nose-only to aerosolized ATRA (target concentration-time of 3000 or 15,000 mg-min/m3) or by injecting them intraperitoneally with ATRA in cottonseed oil (0.5 or 2.5 mg/kg). Based on estimates of particle deposition in the respiratory tract, inhalation doses were chosen to be consistent with injected doses. Lungs were fixed by inflation with formalin (constant pressure for 6 hours followed by >48 hours of immersion) and were embedded in paraffin. Sections were evaluated by histopathology and stereology. Inhalation exposure to ATRA at both aerosol concentrations caused significant elevations of ATRA in the lung, whereas only the high-dose injection treatment was associated with an elevation of lung ATRA. The mean ATRA concentration from lungs of rats in the high-dose inhalation exposure groups as measured by liquid chromatography--mass spectrometry was approximately 12-fold greater than that of high-dose injection-treated rats. Elastase instillation caused increased lung volumes, irregular alveolar air space enlargement, and fragmentation and attenuation of alveolar septa. Neither inhaled nor injected ATRA reduced the enlarged lung volumes associated with this emphysema model. Stereology demonstrated that alveolar air space enlargement in ATRA-treated rats was similar to that in sham-treated emphysematous animals. Thus

  9. All-trans retinoic acid protects against arsenic-induced uterine toxicity in female Sprague-Dawley rats

    Energy Technology Data Exchange (ETDEWEB)

    Chatterjee, A.; Chatterji, U., E-mail: urmichatterji@gmail.com

    2011-12-15

    Background and purpose: Arsenic exposure frequently leads to reproductive failures by disrupting the rat uterine histology, hormonal integrity and estrogen signaling components of the rat uterus, possibly by generating reactive oxygen species. All-trans retinoic acid (ATRA) was assessed as a prospective therapeutic agent for reversing reproductive disorders. Experimental approach: Rats exposed to arsenic for 28 days were allowed to either recover naturally or were treated simultaneously with ATRA for 28 days or treatment continued up to 56 days. Hematoxylin-eosin double staining was used to evaluate changes in the uterine histology. Serum gonadotropins and estradiol were assayed by ELISA. Expression of the estrogen receptor (ER{alpha}), an estrogen responsive gene vascular endothelial growth factor (VEGF), and cell cycle regulatory proteins, cyclin D1 and CDK4, was assessed by RT-PCR, immunohistochemistry and western blot analysis. Key results: ATRA ameliorated sodium arsenite-induced decrease in circulating estradiol and gonadotropin levels in a dose- and time-dependent manner, along with recovery of luminal epithelial cells and endometrial glands. Concomitant up regulation of ER{alpha}, VEGF, cyclin D1, CDK4 and Ki-67 was also observed to be more prominent for ATRA-treated rats as compared to the rats that were allowed to recover naturally for 56 days. Conclusions and implications: Collectively, the results reveal that ATRA reverses arsenic-induced disruption of the circulating levels of gonadotropins and estradiol, and degeneration of luminal epithelial cells and endometrial glands of the rat uterus, indicating resumption of their functional status. Since structural and functional maintenance of the pubertal uterus is under the influence of estradiol, ATRA consequently up regulated the estrogen receptor and resumed cellular proliferation, possibly by an antioxidant therapeutic approach against arsenic toxicity. Highlights: Black-Right-Pointing-Pointer Arsenic

  10. Low-dose decitabine plus all-trans retinoic acid in patients with myeloid neoplasms ineligible for intensive chemotherapy.

    Science.gov (United States)

    Wu, Wei; Lin, Yan; Xiang, Lili; Dong, Weimin; Hua, Xiaoying; Ling, Yun; Li, Haiqian; Yan, Feng; Xie, Xiaobao; Gu, Weiying

    2016-06-01

    In our previous in vitro trials, decitabine and all-trans retinoic acid (ATRA) demonstrated synergistic effects on growth inhibition, differentiation, and apoptosis in SHI-1 cells; in K562 cells, ATRA enhanced the effect of decitabine on p16 demethylation, and the combination of the two drugs was found to activate RAR-β expression (p16 and RAR-β are two tumor suppressor genes). On the rationale of our in vitro trials, we used low-dose decitabine and ATRA to treat 31 myeloid neoplasms deemed ineligible for intensive chemotherapy. The regimen consisted of decitabine at the dose of 15 mg/m(2) intravenously over 1 h daily for consecutive 5 days and ATRA at the dose of 20 mg/m(2) orally from day 1 to 28 except day 4 to 28 in the first cycle, and the regimen was repeated every 28 days. After 6 cycles, decitabine treatment was stopped, and ATRA treatment was continued for maintenance treatment. Treated with a median of 2 cycles (range 1-6), 7 patients (22.6 %) achieved complete remission (CR), 7 (22.6 %) marrow CR (mCR), and 4 (12.9 %) partial remission (PR). The overall remission (CR, mCR, and PR) rate was 58.1 %, and the best response (CR and mCR) rate was 45.2 %. The median overall survival (OS) was 11.0 months, the 1-year OS rate was 41.9 %, and the 2-year OS rate was 26.6 %. In univariate analyses, age, performance status, comorbidities, white blood cell counts and platelets at diagnosis, percentage of bone marrow blasts, karyotype, and treatment efficacy demonstrated no impacts on OS (P > 0.05, each). Main side effects were tolerable hematologic toxicities. In conclusion, low-dose decitabine plus ATRA is a promising treatment for patients with myeloid neoplasms judged ineligible for intensive chemotherapy.

  11. Retinoic Acid-Induced Epidermal Transdifferentiation in Skin

    Directory of Open Access Journals (Sweden)

    Yoshihiro Akimoto

    2014-06-01

    Full Text Available Retinoids function as important regulatory signaling molecules during development, acting in cellular growth and differentiation both during embryogenesis and in the adult animal. In 1953, Fell and Mellanby first found that excess vitamin A can induce transdifferentiation of chick embryonic epidermis to a mucous epithelium (Fell, H.B.; Mellanby, E. Metaplasia produced in cultures of chick ectoderm by high vitamin A. J. Physiol. 1953, 119, 470–488. However, the molecular mechanism of this transdifferentiation process was unknown for a long time. Recent studies demonstrated that Gbx1, a divergent homeobox gene, is one of the target genes of all-trans retinoic acid (ATRA for this transdifferentiation. Furthermore, it was found that ATRA can induce the epidermal transdifferentiation into a mucosal epithelium in mammalian embryonic skin, as well as in chick embryonic skin. In the mammalian embryonic skin, the co-expression of Tgm2 and Gbx1 in the epidermis and an increase in TGF-β2 expression elicited by ATRA in the dermis are required for the mucosal transdifferentiation, which occurs through epithelial-mesenchymal interaction. Not only does retinoic acid (RA play an important role in mucosal transdifferentiation, periderm desquamation, and barrier formation in the developing mammalian skin, but it is also involved in hair follicle downgrowth and bending by its effect on the Wnt/β-catenin pathway and on members of the Runx, Fox, and Sox transcription factor families.

  12. CHARACTERIZATION OF CYPS IN THE METABOLISM OF ALL TRANS RETINOIC ACID BY LIVER MICROSOMES FROM MICE TREATED WITH CONAZOLES

    Science.gov (United States)

    Conazoles are fungicides used in crop protection and as pharmaceuticals. Triadimefon and propiconazole are hepatotumorigenic in mice, while myclobutanil is not. Previous toxicogenomic studies suggest that alteration of the retinoic acid metabolism pathway may involve in conazole-...

  13. A Complicated Case of Acute Promyelocytic Leukemia in the Second Trimester of Pregnancy Successfully Treated with All-trans-Retinoic Acid.

    Science.gov (United States)

    Agarwal, Kanika; Patel, Megha; Agarwal, Vandana

    2015-01-01

    A 40-year-old female at 26-week gestation was diagnosed with acute promyelocytic leukemia (APL) after an abnormal prenatal lab workup showed pancytopenia. She was treated with all-trans-retinoic acid (ATRA), idarubicin, and dexamethasone. After day one of treatment, she developed differentiation syndrome, which was treated with dexamethasone. At 30-week gestation, she had preterm premature rupture of membranes and delivered by cesarean section because of the fetus' breech presentation. Despite ATRA's potential for teratogenicity, a viable infant was born without apparent anomalies. Postpartum, she underwent consolidation treatment with ATRA and arsenic trioxide (ATO). The patient continued ATRA therapy after delivery and is currently in remission.

  14. [Successful treatment of acute promyelocytic leukemia in a pregnant patient with all-trans retinoic acid and chemotherapy resulting in a safe delivery].

    Science.gov (United States)

    Itoh, Mitsuru; Takao, Sumiko; Yago, Kazuhiro; Shimada, Hideto

    2003-06-01

    A 32-year-old woman at 21 gestational weeks was admitted because of leukocytosis with DIC. She was diagnosed as having acute promyelocytic leukemia and treated with all-trans retinoic acid (70 mg/body) in combination with daunorubicin and cytosine arabinoside. She achieved complete remission, and continuously received a second treatment with daunorubicin and cytosine arabinoside. Cesarean section was performed, and a live male infant was born in the 30th week of pregnancy. The mother and baby have progressed excellently to date. In a such case, the choice of treatment and time of birth should be considered depending on the individual situation.

  15. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) alters the endogenous metabolism of all-trans-retinoic acid in the rat

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Carsten K.; Nau, Heinz [Department of Food Toxicology, School of Veterinary Medicine Hannover, Bischofsholer Damm 15, 30173, Hannover (Germany); Hoegberg, Pi; Fletcher, Nicholas; Nilsson, Charlotte B.; Trossvik, Christina; Haakansson, Helen [Institute of Environmental Medicine, Karolinska Institutet, 17177, Stockholm (Sweden)

    2003-07-01

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is known to influence vitamin A homeostasis. In order to investigate the mechanism behind this retinoid disruption, male Sprague-Dawley rats were exposed to TCDD at doses ranging from 0.1 to 100 {mu}g/kg body weight, and were killed 3 days after exposure. Additional groups of rats were killed 1 and 28 days after a single oral dose of 10 {mu}g TCDD/kg body weight. Serum, kidney, and liver were investigated for retinoid levels, as well as gene expression and enzyme activities relevant for retinoid metabolism. Besides the well known effects of TCDD on apolar retinoids, i.e. decreased hepatic and increased renal retinyl ester (RE) levels, we have found dose-dependent elevation of all-trans-retinoic acid (all-trans-RA) levels in all investigated tissues. In the liver, 9-cis-4-oxo-13,14-dihydro-RA was drastically decreased by TCDD in a dose-dependent manner. In serum, cis-isomers of all-trans-RA, including 9,13-di-cis-RA, were significantly reduced already at the lowest dose level. Protein and mRNA levels of cellular retinol binding protein I (CRBP-I) in liver or kidneys were not significantly altered by TCDD exposure at doses at which retinoid levels were affected, making CRBP-I an unlikely candidate to account for the alterations in retinoid metabolism caused by TCDD. The expression and activities of relevant cytochrome P450 (CYP) enzymes with potential roles in all-trans-RA synthesis and/or degradation (CYP1A1, 1A2, and 2B1/2) were also monitored. A possible role of CYP1A1 in TCDD-induced all-trans-RA synthesis is suggested from the time-course relationship between CYP1A1 activity and all-trans-RA levels in liver and kidney. The significant alteration of the all-trans-RA metabolism has the potential to contribute significantly to the toxicity of TCDD. (orig.)

  16. Simple in vitro migration assay for neural crest cells and the opposite effects of all-trans-retinoic acid on cephalic- and trunk-derived cells.

    Science.gov (United States)

    Usami, Makoto; Mitsunaga, Katsuyoshi; Irie, Tomohiko; Miyajima, Atsuko; Doi, Osamu

    2014-08-01

    Here, we describe a simple in vitro neural crest cell (NCC) migration assay and the effects of all-trans-retinoic acid (RA) on NCCs. Neural tubes excised from the rhombencephalic or trunk region of day 10.5 rat embryos were cultured for 48 h to allow emigration and migration of NCCs. Migration of NCCs was measured as the change in the radius (radius ratio) calculated from the circular spread of NCCs between 24 and 48 h of culture. RA was added to the culture medium after 24 h at embryotoxic concentrations determined by rat whole embryo culture. RA (10 μM) reduced the migration of cephalic NCCs, whereas it enhanced the migration of trunk NCCs, indicating that RA has opposite effects on these two types of NCCs.

  17. A Complicated Case of Acute Promyelocytic Leukemia in the Second Trimester of Pregnancy Successfully Treated with All-trans-Retinoic Acid

    Directory of Open Access Journals (Sweden)

    Kanika Agarwal

    2015-01-01

    Full Text Available A 40-year-old female at 26-week gestation was diagnosed with acute promyelocytic leukemia (APL after an abnormal prenatal lab workup showed pancytopenia. She was treated with all-trans-retinoic acid (ATRA, idarubicin, and dexamethasone. After day one of treatment, she developed differentiation syndrome, which was treated with dexamethasone. At 30-week gestation, she had preterm premature rupture of membranes and delivered by cesarean section because of the fetus’ breech presentation. Despite ATRA’s potential for teratogenicity, a viable infant was born without apparent anomalies. Postpartum, she underwent consolidation treatment with ATRA and arsenic trioxide (ATO. The patient continued ATRA therapy after delivery and is currently in remission.

  18. COMPARISON OF CLINICAL OBSERVATIONS BETWEEN PATIENTS WITH ACUTE PROMYELOCYTIC LEUKEMIA TREATED WITH ALL-TRANS RETINOIC ACID AND CHEMOTHERAPY

    Institute of Scientific and Technical Information of China (English)

    张芬琴; 吴立德; 李秀松; 孙关林; 蔡敬仁; 王振义

    1992-01-01

    Clinical observations were retrospectively compared between 2 matched groups of patients with acute promyelocytic leukemia (APL) each 20. The first group were treated with chemotherapy, the other with all-tram retinoic acid (ATRA) alone at a dose of 45-60mg/M~2/d. The complete remission (CR) rate of ATRA group was significantly higher than that of chemotherapy (90% vs 55%). The time for obtaining CR as well as the duration of fever and hospitalization were shorter and the amount of blood transfused was less in the former than in the latter group. Seven cases were complicated by DIC and 4 died in the group of chemotherapy, while no case was by of DIC or death in the ATRA group. The mechanism was discussed. ATRA is an alternative effective drug for remission induction therapy in APL with high rate of CR.

  19. All-trans retinoic acid as a single agent induces complete remission in a patient with acute leukemia of M2a subtype

    Institute of Scientific and Technical Information of China (English)

    陈子兴; 王阳; 王玮; 贡静霞; 薛永权

    2002-01-01

    Objective To present a special case with the karyotype and molecular marker of acute myeloid leukemia (AML)-M2 who was induced to complete remission by all-trans retinoic acid (ATRA) alone.Methods A recently hospitalized young female patient with acute leukemia was initially diagnosed as M3 subtype based on morphological French-American-British (FAB) classification. Karyotype analysis using standard G and R banding techniques and RT-PCR were applied to further define the diagnosis. After primarily cultured bone marrow cells from the iliac aspiration were tested for in vitro induced differentiation, the patient was treated with oral all-trans retinoic acid alone, 60?mg per day until complete remission was achieved. Peripheral blood and bone marrow changes were monitored over the whole treatment course.Results The characteristic chromosomal aberration for M3, the t(15;17) reciprocal translocation, was not found while a t(8;21) translocation was verified. Furthermore, an amplified product of the AML-1/ETO fusion gene instead of the PML/RARα fusion gene was detected by RT-PCR and the diagnosis was corrected from M3 to M2. Primary cultured bone marrow cells can be fully induced to terminal differentiation after 4 days exposure to ATRA. A hematological complete remission was achieved after 40 days treatment with ATRA as a single therapeutic agent, suggesting an alternative pathway mediating ATRA-induced myeloid differentiation. Conclusion A leukemia patient with a subtype other than M3, such as M2 in this case, may also be induced to complete remission by the mechanism of ATRA-induced terminal differentiation. This implies that there may be a pathway other than PML/RARα fusion gene product which mediates ATRA-induced myeloid maturation in leukemia cells.

  20. Ethanol elevates physiological all-trans-retinoic acid levels in select loci through altering retinoid metabolism in multiple loci: a potential mechanism of ethanol toxicity

    Science.gov (United States)

    Kane, Maureen A.; Folias, Alexandra E.; Wang, Chao; Napoli, Joseph L.

    2010-01-01

    All-trans-retinoic acid (atRA) supports embryonic development, central nervous system function, and the immune response. atRA initiates neurogenesis and dendritic growth in the hippocampus and is required for spatial memory; superphysiological atRA inhibits neurogenesis, causes teratology and/or embryo toxicity, and alters cognitive function and behavior. Because abnormal atRA shares pathological conditions with alcoholism, inhibition of retinol (vitamin A) activation into atRA has been credited widely as a mechanism of ethanol toxicity. Here, we analyze the effects of ethanol on retinoid concentrations in vivo during normal vitamin A nutriture, using sensitive and analytically robust assays. Ethanol either increased or had no effect on atRA, regardless of changes in retinol and retinyl esters. Acute ethanol (3.5 g/kg) increased atRA in adult hippocampus (1.6-fold), liver (2.4-fold), and testis (1.5-fold). Feeding dams a liquid diet with 6.5% ethanol from embryonic day 13 (e13) to e19 increased atRA in fetal hippocampus (up to 20-fold) and cortex (up to 50-fold), depending on blood alcohol content. One-month feeding of the 6.5% ethanol diet increased atRA in adult hippocampus (20-fold), cortex (2-fold), testis (2-fold), and serum (10-fold). Tissue-specific increases in retinoid dehydrogenase mRNAs and activities, extrahepatic retinol concentrations, and atRA catabolism combined to produce site-specific effects. Because a sustained increase in atRA has deleterious effects on the central nervous system and embryo development, these data suggest that superphysiological atRA contributes to ethanol pathological conditions, including cognitive dysfunction and fetal alcohol syndrome.—Kane, M. A., Folias, A. E., Wang, C., Napoli, J. L. Ethanol elevates physiological all-trans-retinoic acid levels in select loci through altering retinoid metabolism in multiple loci: a potential mechanism of ethanol toxicity. PMID:19890016

  1. Combination of nanoparticle-delivered siRNA for Astrocyte elevated gene-1 (AEG-1) and all-trans retinoic acid (ATRA): an effective therapeutic strategy for hepatocellular carcinoma (HCC)

    Science.gov (United States)

    Rajasekaran, Devaraja; Srivastava, Jyoti; Ebeid, Kareem; Gredler, Rachel; Akiel, Maaged; Jariwala, Nidhi; Robertson, Chadia L.; Shen, Xue-Ning; Siddiq, Ayesha; Fisher, Paul B.; Salem, Aliasger K.; Sarkar, Devanand

    2016-01-01

    Hepatocellular carcinoma (HCC) is a fatal cancer with no effective therapy. Astrocyte elevated gene-1 (AEG-1) plays a pivotal role in hepatocarcinogenesis and inhibits retinoic acid-induced gene expression and cell death. Combination of a lentivirus expressing AEG-1 shRNA and all-trans retinoic acid (ATRA) profoundly and synergistically inhibited subcutaneous human HCC xenografts in nude mice. We now have developed liver-targeted nanoplexes by conjugating poly(amidoamine) (PAMAM) dendrimers with polyethylene glycol (PEG) and lactobionic acid (Gal) (PAMAM-PEG-Gal) which were complexed with AEG-1 siRNA (PAMAM-AEG-1si). The polymer conjugate was characterized by 1H-NMR, MALDI and mass spectrometry, and optimal nanoplex formulations were characterized for surface charge, size and morphology. Orthotopic xenografts of human HCC cell QGY-7703 expressing luciferase (QGY-luc) were established in the livers of athymic nude mice and tumor development was monitored by bioluminescence imaging (BLI). Tumor-bearing mice were treated with PAMAM-siCon, PAMAM-siCon+ATRA, PAMAM-AEG-1si and PAMAM-AEG-1si+ATRA. In the control group the tumor developed aggressively. ATRA showed little effect due to high AEG-1 levels in QGY-luc cells. PAMAM-AEG-1si showed significant reduction in tumor growth and the combination of PAMAM-AEG-1si+ATRA showed profound and synergistic inhibition so that the tumors were almost undetectable by BLI. A marked decrease in AEG-1 level was observed in tumor samples treated with PAMAM-AEG-1si. The group treated with PAMAM-AEG-1si+ATRA nanoplexes showed increased necrosis, inhibition of proliferation and increased apoptosis when compared to other groups. Liver is an ideal organ for RNAi therapy and ATRA is an approved anti-cancer agent. Our exciting observations suggest that the combinatorial approach might be an effective way to combat HCC. PMID:26079152

  2. Risk-adapted treatment of acute promyelocytic leukemia based on all-trans retinoic acid and anthracycline with addition of cytarabine in consolidation therapy for high-risk patients: Further improvements in treatment outcome

    NARCIS (Netherlands)

    M.A. Sanz (Miguel Angel); P. Montesinos (Pau); C. Rayón (Chelo); A. Holowiecka (Aleksandra); J. De La Serna (Javier); G. Milone (Gustavo); E. de Lisa (Elena); S. Brunet (Salut); V. Rybio (Vicente); J.M. Ribera (Josep Maria); C. Rivas (Concha); I. Krsnik (Isabel); J.M. Bergua (Juan Miguel); J.D. González (José David); J. Díaz-Mediavilla (Joaquín); R. Rojas (Rafael); F. Manso (Félix); G.J. Ossenkoppele (Gert); B. Löwenberg (Bob)

    2010-01-01

    textabstractA risk-adapted strategy based on all-trans retinoic acid (ATRA) and anthracycline monochemotherapy (PETHEMALPA99 trial) has demonstrated a high antileukemic efficacy in acute promyelocytic leukemia. We designed a new trial (LPA2005) with the objective of achieving stepwise improvements i

  3. Risk-adapted treatment of acute promyelocytic leukemia with all-trans retinoic acid and anthracycline monochemotherapy: Long-term outcome of the LPA 99 multicenter study by the PETHEMA Group

    NARCIS (Netherlands)

    M.A. Sanz (Miguel Angel); P. Montesinos (Pau); E. Vellenga (Edo); C. Rayón (Consuelo); J. de Serna (Javier); R. Parody (Ricardo); J.M. Bergua (Juan Miguel); A. León (Angel); S. Negri (Silvia); M. González (Marcos); C. Rivas (Concha); J. Esteve (Jordi); G. Milone (Gustavo); E. Amutio (Elena); S. Brunet (Salut); J. García-Laraña; D. Colomer (Dolors); M.J. Calasanz (Maria); C. Chillón (Carmen); E. Barragán (Eva); P. Bolufer (Pascual); B. Löwenberg (Bob)

    2008-01-01

    textabstractA previous report of the Programa de Estudio y Tratamiento de las Hemopatfas Malignas (PETHEMA) Group showed that a risk-adapted strategy combining all-trans retinoic acid (ATRA) and anthracycline monochemotherapy for induction and consolidation in newly diagnosed acute promyelocytic leu

  4. All-trans retinoic acid with daunorubicin or idarubicin for risk-adapted treatment of acute promyelocytic leukaemia : a matched-pair analysis of the PETHEMA LPA-2005 and IC-APL studies

    NARCIS (Netherlands)

    Sanz, Miguel A.; Montesinos, Pau; Kim, Haesook T.; Ruiz-Argueelles, Guillermo J.; Undurraga, Maria S.; Uriarte, Maria R.; Martinez, Lem; Jacomo, Rafael H.; Gutierrez-Aguirre, Homero; Melo, Raul A. M.; Bittencourt, Rosane; Pasquini, Ricardo; Pagnano, Katia; Fagundes, Evandro M.; Vellenga, Edo; Holowiecka, Alexandra; Gonzalez-Huerta, Ana J.; Fernandez, Pascual; De la Serna, Javier; Brunet, Salut; De Lisa, Elena; Gonzalez-Campos, Jose; Ribera, Jose M.; Krsnik, Isabel; Ganser, Arnold; Berliner, Nancy; Ribeiro, Raul C.; Lo-Coco, Francesco; Lowenberg, Bob; Rego, Eduardo M.

    2015-01-01

    Front-line treatment of acute promyelocytic leukaemia (APL) consists of all-trans retinoic acid (ATRA) and anthracycline-based chemotherapy. In this setting, a comparison of idarubicin and daunorubicin has never been carried out. Two similar clinical trials using ATRA and chemotherapy for newly diag

  5. Risk-adapted treatment of acute promyelocytic leukemia with all-trans retinoic acid and anthracycline monochemotherapy : long-term outcome of the LPA 99 multicenter study by the PETHEMA Group

    NARCIS (Netherlands)

    Sanz, Miguel A.; Montesinos, Pau; Vellenga, Edo; Rayon, Consuelo; de la Serna, Javier; Parody, Ricardo; Bergua, Juan M.; Leon, Angel; Negri, Silvia; Gonzalez, Marcos; Rivas, Concha; Esteve, Jordi; Milone, Gustavo; Gonzalez, Jose D.; Amutio, Elena; Brunet, Salut; Garcia-Larana, J.; Colomer, Dolors; Calasanz, Maria J.; Chillon, Carmen; Barragan, Eva; Bolufer, Pascual; Lowenberg, Bob

    2008-01-01

    A previous report of the Programa de Estudio y Tratamiento de las Hemopatias Malignas (PETHEMA) Group showed that a risk-adapted strategy combining all-trans retinoic acid (ATRA) and anthracycline monochemotherapy for induction and consolidation in newly diagnosed acute promyelocytic leukemia result

  6. The all-trans retinoic acid (atRA)-regulated gene Calmin (Clmn) regulates cell cycle exit and neurite outgrowth in murine neuroblastoma (Neuro2a) cells

    Energy Technology Data Exchange (ETDEWEB)

    Marzinke, Mark A. [Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706-1544 (United States); Clagett-Dame, Margaret, E-mail: dame@biochem.wisc.edu [Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706-1544 (United States); Pharmaceutical Science Division, University of Wisconsin-Madison, Madison, WI 53705-2222 (United States)

    2012-01-01

    The vitamin A metabolite all-trans retinoic acid (atRA) functions in nervous system development and regulates cell proliferation and differentiation. Neuroblastoma cells (SH-SY5Y and Neuro2a or N2A) exposed to atRA undergo growth inhibition and neuronal differentiation, both of which are preceded by an increase in Clmn mRNA. Treatment of N2A cells with atRA produces a reduction in phosphohistone 3 immunostaining and BrdU incorporation, both indicators of a reduction in cell proliferation. These effects are nearly eliminated in atRA-treated shClmn knockdown cells. Loss of Clmn in the mouse N2A cell line also results in a significant reduction of atRA-mediated neurite outgrowth, a response that can be rescued by reintroduction of the Clmn sequence. In contrast, ectopic overexpression of Clmn produces an increase in the cyclin dependent kinase inhibitor, p21{sup Cip1}, a decrease in cyclin D1 protein and an increase in hypophosphorylated Rb, showing that Clmn participates in G{sub 1}/S arrest. Clmn overexpression alone is sufficient to inhibit N2A cell proliferation, whereas both Clmn and atRA must be present to induce neurite outgrowth. This study shows that the atRA-responsive gene Clmn promotes exit from the cell cycle, a requisite event for neuronal differentiation. -- Highlights: Black-Right-Pointing-Pointer Calmin is a retinoic acid-responsive gene. Black-Right-Pointing-Pointer Calmin promotes cell cycle exit in N2A cells. Black-Right-Pointing-Pointer Calmin overexpression increases p21Cip1 and decreases cyclin D1. Black-Right-Pointing-Pointer Calmin is required for RA-induced growth inhibition and neurite outgrowth.

  7. Inhibition effects of all trans-retinoic acid on the growth and angiogenesis of esophageal squamous cell carcinoma in nude mice

    Institute of Scientific and Technical Information of China (English)

    LU Tai-ying; LI Wen-cai; CHEN Ren-yin; FAN Qing-xia; WANG Liu-xing; WANG Rui-lin; LU Shi-xin; MENG Hui

    2011-01-01

    Background The potential application of retinoic acid receptor activators,such as all trans-retinoic acid (ATRA),for treating various cancers have been studied both pre-clinically and clinically.Whether ATRA has an anticancer effect on human esophageal squamous cancer cell (ESCC) is still unknown.We have explored the anticancer effect of ATRA in ESCC,and in this study,the effects of ATRA on levels and patterns of expression of the vascular endothelial growth factor (VEGF) signal transduction pathway in transplantable tumor growth of the human ESCC cell line,EC9706,in nude mice.Methods The animal model of the ESCC xenograft was made by subcutaneous implantation of tumor cells into nude mice.Reverse transcription-polymerase chain reaction (RT-PCR),Western blotting and immunohistochemical assays were used to detect the expression of the VEGF signal transduction pathway in ESCC xenograft tissues.Results Compared to the control group,the tumor inhibition rates in the low dose ATRA,high dose ATRA,and 5-FU groups were 83.21%,88.32%,91.02%,respectively.The protein and mRNA levels of VEGF were down-regulated after being treated with ATRA and 5-FU compared to the control group (P <0.05).The study also revealed that ATRA specifically down-regulated VEGF and the component of the VEGF signal transduction pathway of CD31,CD34,and CD105 (component of the TGF-β receptor) in ESCC xenograft tissues (P <0.05).Conclusions ATRA can significantly inhibit tumor growth and has anticancer effects on transplantable tumor growth of human ESCC cell line EC9706 in nude mice.These findings indicate that ATRA specifically down regulated VEGF and the components of VEGF signal transduction,which may be an important mechanism responsible for the neoangiogenesis inhibition of ESCC cells.

  8. All-trans-retinoic acid reduces BACE1 expression under inflammatory conditions via modulation of nuclear factor κB (NFκB) signaling.

    Science.gov (United States)

    Wang, Ruishan; Chen, Shaoya; Liu, Yingchun; Diao, Shiyong; Xue, Yueqiang; You, Xiaoqing; Park, Edwards A; Liao, Francesca-Fang

    2015-09-11

    Insulin resistance and neuroinflammation have emerged as two likely key contributors in the pathogenesis of Alzheimer disease (AD), especially in those sporadic AD cases compromised by diabetes or cardiovascular disease. Amyloid-β (Aβ) deposition and its associated inflammatory response are hallmarks in sporadic AD brains. Elevated expression and activity of β-secretase 1 (BACE1), the rate-limiting enzyme responsible for the β-cleavage of amyloid precursor proteins to Aβ peptides, are also observed in sporadic AD brains. Previous studies have suggested that there is therapeutic potential for retinoic acid in treating neurodegeneration based on decreased Aβ. Here we discovered that BACE1 expression is elevated in the brains of both Tg2576 transgenic mice and mice on high fat diets. These conditions are associated with a neuroinflammatory response. We found that administration of all-trans-retinoic acid (atRA) down-regulated the expression of BACE1 in the brains of Tg2576 mice and in mice fed a high fat diet. Moreover, in LPS-treated mice and cultured neurons, BACE1 expression was repressed by the addition of atRA, correlating with the anti-inflammatory efficacy of atRA. Mutations of the NFκB binding site in BACE1 promoter abolished the suppressive effect of atRA. Furthermore, atRA disrupted LPS-induced nuclear translocation of NFκB and its binding to BACE1 promoter as well as promoting the recruitment of the corepressor NCoR. Our findings indicate that atRA represses BACE1 gene expression under inflammatory conditions via the modulation of NFκB signaling.

  9. All-trans retinoic acid (ATRA)-induced apoptosis is preceded by G1 arrest in human MCF-7 breast cancer cells.

    Science.gov (United States)

    Mangiarotti, R; Danova, M; Alberici, R; Pellicciari, C

    1998-01-01

    In this study the effects of all-trans retinoic acid (ATRA) on cell cycle and apoptosis of MCF-7 human breast cancer cells were investigated to elucidate the mechanisms underlying the antineoplastic potential of this retinoid in breast cancer. The antiproliferative effect of ATRA was evaluated by DNA content measurements and dual-parameter flow cytometry of bromodeoxyuridine (BrdU) incorporation and of the expression of cell cycle-related proteins (Ki-67 as proliferation marker and statin as quiescence marker) vs DNA content. Apoptosis was also studied by flow cytometry of either DNA content or Annexin V labelling. After 10(-6) M ATRA treatment, the fraction of S-phase cells decreased significantly, and cells accumulated in the G0/G1 range of DNA contents. Dual-parameter flow cytograms showed a decrease in the percentage of Ki-67-labelled cells (after 10 days, only 20% of the cells were still positive for Ki-67 compared with 95% in controls), while the fraction of statin-positive cells increased slightly. From 3 days of treatment onwards, apoptosis was found to occur. These results show that ATRA-induced inhibition of MCF-7 cell growth is related to two mechanisms, i.e. the block of cell proliferation, mostly in a pre-S phase, and the induction of apoptosis. These results should be taken into account when attempting to design treatment programmes that associate ATRA with antineoplastic compounds of different cell cycle specificity.

  10. Amelioration of glomerulosclerosis with all-trans retinoic acid is linked to decreased plasminogen activator inhibitor-1 and α-smooth muscle actin

    Institute of Scientific and Technical Information of China (English)

    Xia LIU; Lei L(U); Bei-bei TAO; Ai-ling ZHOU; Yi-chun ZHU

    2011-01-01

    Aim:To examine the effects of all-trans retinoic acid (atRA) on renal morphology and function as well as on renal plasminogen activator inhibitor-1 (PAI-1) expression and plasmin activity in rats with 5/6 nephrectomy.Methods:Adult male Sprague Dawley rats were given 5/6 nephrectomy or sham operation. Renal function was measured 2 weeks later. The nephrectomized rats were assigned to groups matched for proteinuria and treated with vehicle or atRA (5 or 10 mg/kg by gastric gavage once daily) for the next 12 weeks. Rats with sham operation were treated with vehicle. At the end of the treatments,kidneys were collected for histological examination, Western blot analysis, and enzymatic activity measurements.Results:The 5/6 nephrectomy promoted hypertension, renal dysfunction, and glomerulosclerosis. These changes were significantly reduced in the atRA-treated group. The expressions of PAI-1 and α-smooth muscle actin (α-SMA) were significantly increased in the vehicle-treated nephrectomized rats. Treatment with atRA significantly reduced the expressions of PAI-1 and α-SMA. However, piasmin activity remained unchanged following atRA treatment.Conclusion:Treatment with atRA ameliorates glomerulosclerosis and improves renal function in rats with 5/6 nephrectomy. This is associated with a decrease in PAI-1 and α-SMA, but not with a change in plasmin activity.

  11. Effects of all-trans-retinoic acid on the expression and tyrosine phosphorylation of gap junction connexin 43 in HeLa cell line and its significance

    Institute of Scientific and Technical Information of China (English)

    CHEN Bi-liang; MA Xiang-dong; XIN Xiao-yan; WANG De-tang; WANG Chun-mei

    2001-01-01

    Objective: To investigate the signal transduction mechanism of gap junctional genes connexin43 in human cervical carcinogenesis. Methods: Human cervical carcinoma cell line HeLa was cultured and treated by all-trans-retinoic acid (ATRA). Flow cytometer (FCM) was employed to detect expression of Cx43 protein in HeLa cells. Fluo-3 AM loading and laser scanning confocal microscope (LSCM) were used to measure the concentrations of intracellular calcium ([Ca2+]i) in HeLa cells. Phosphorylation on tyrosine of connexin43 protein was examined by immunoblot. Results: The positive rate of Cx43 protein increased from 1.9% in untreated HeLa cells to 26.3% in RA-treated HeLa cells as shown by FCM. [Ca2+]i was 35.73 nmol/L in untreated HeLa cells which was increased to 58.16 nmol/L in ATRA-treated cells.Immunoblot showed that ATRA-treated HeLa cells had phosphorylation on tyrosine in Cx43 protein whereas untreated cells had not. Conclusions: Carcinogenesis of human cervical carcinoma is related with the abnormal expression of cx43gene and disorder of signal transduction manifested as the decrease of [Ca2+]i and post-translation phosphorylation on tyrosine of Cx43 protein. The anti-tumor effect of ATRA in HeLa cells might be due to the up-regulation of cx43 gene and its signal transduction pathway.

  12. Co-delivery of all-trans-retinoic acid and doxorubicin for cancer therapy with synergistic inhibition of cancer stem cells.

    Science.gov (United States)

    Sun, Rong; Liu, Yang; Li, Shi-Yong; Shen, Song; Du, Xiao-Jiao; Xu, Cong-Fei; Cao, Zhi-Ting; Bao, Yan; Zhu, Yan-Hua; Li, Ya-Ping; Yang, Xian-Zhu; Wang, Jun

    2015-01-01

    Combination treatment through simultaneous delivery of two or more drugs with nanoparticles has been demonstrated to be an elegant and efficient approach for cancer therapy. Herein, we employ a combination therapy for eliminating both the bulk tumor cells and the rare cancer stem cells (CSCs) that have a high self-renewal capacity and play a critical role in cancer treatment failure. All-trans-retinoic acid (ATRA), a powerful differentiation agent of cancer stem cells and the clinically widely used chemotherapy agent doxorubicin (DOX) are simultaneously encapsulated in the same nanoparticle by a single emulsion method. It is demonstrated that ATRA and DOX simultaneous delivery-based therapy can efficiently deliver the drugs to both non-CSCs and CSCs to differentiate and kill the cancer cells. Differentiation of CSCs into non-CSCs can reduce their self-renewal capacity and increase their sensitivity to chemotherapy; with the combined therapy, a significantly improved anti-cancer effect is demonstrated. Administration of this combinational drug delivery system can markedly augment the enrichment of drugs both in tumor tissues and cancer stem cells, prodigiously enhancing the suppression of tumor growth while reduce the incidence of CSC in a synergistic manner.

  13. Tracing anti-cancer and cancer-promoting actions of all-trans retinoic acid in breast cancer to a RARα epigenetic mechanism of mammary epithelial cell fate.

    Science.gov (United States)

    Rossetti, Stefano; Ren, MingQiang; Visconti, Nicolo; Corlazzoli, Francesca; Gagliostro, Vincenzo; Somenzi, Giulia; Yao, Jin; Sun, Yijun; Sacchi, Nicoletta

    2016-12-27

    A hallmark of cancer cells is the ability to evade the growth inhibitory/pro-apoptotic action of physiological all-trans retinoic acid (RA) signal, the bioactive derivative of Vitamin A. However, as we and others reported, RA can also promote cancer cell growth and invasion. Here we show that anticancer and cancer-promoting RA actions in breast cancer have roots in a mechanism of mammary epithelial cell morphogenesis that involves both transcriptional (epigenetic) and non-transcriptional RARα (RARA) functions. We found that the mammary epithelial cell-context specific degree of functionality of the RARA transcriptional (epigenetic) component of this mechanism, by tuning the effects of the non-transcriptional RARA component, determines different cell fate decisions during mammary morphogenesis. Indeed, factors that hamper the RARA epigenetic function make physiological RA drive aberrant morphogenesis via non-transcriptional RARA, thus leading to cell transformation. Remarkably, also the cell context-specific degree of functionality of the RARA epigenetic component retained by breast cancer cells is critical to determine cell fate decisions in response to physiological as well as supraphysiological RA variation. Overall this study supports the proof of principle that the epigenetic functional plasticity of the mammary epithelial cell RARA mechanism, which is essential for normal morphogenetic processes, is necessary to deter breast cancer onset/progression consequent to the insidious action of physiological RA.

  14. Interon-gamma Enhances the Antitumor Effect of All-trans Retinoic Acid on Hepatocellular Carcinoma Cells by Inhibiting the Expression of Nuclear Factor-kappaB

    Institute of Scientific and Technical Information of China (English)

    YIN Yuan-qin; WANG Xiao-hua; MA Ping; FU Liye; HANG Tao; WANG Yang

    2008-01-01

    Objective:To explore the combination effects of all-trans retinoic acid(ATRA)with interferon-gamma(IFN-γ)on human hepatocarcinoma cell line SMMC-7721 and the mechanism of action.Methods:SMMC-7721 cells were divided into treated group and control group.The cells were treated with ATRA or ATRA+IFN-γ in the former and added with PBS in the latter.The inhibition rate of SMMC-7721 cell proliferation was detected by MTT,the cell change in morphology was observed by electron microscope.The apoptosis was detected by flow cytometry and the expression changes of nuclear factor-kappaB(NF-κB)was analyzed by Western blotting when the SMMC-7721 cells were treated with ATRA and IFN-γ.Results:The SMMC-7721 cell proliferation was suppressed and apoptosis was induced after the cells were treated with ATRA treatment,and these effects were enhanced when ATRA was combined with IFN-γ.The expression of NF-κB was reduced after SMMC-7721 cell was treated with ATRA,and reduced significantly when the cells were treated with the combination of ATRA and IFN-γ.Conclusion:IFN-γ can enhance the inhibiting effects of ATRA on cell proliferation and inducing apoptosis on SMMC-7721 cell and these effects might be mediated by inhibiting the expression of NF-κB.

  15. Mature adipocyte-derived dedifferentiated fat cells can trans-differentiate into osteoblasts in vitro and in vivo only by all-trans retinoic acid.

    Science.gov (United States)

    Oki, Yoshinao; Watanabe, Saiko; Endo, Tuyoshi; Kano, Koichiro

    2008-01-01

    We investigated whether de-differentiated fat (DFAT) cells, a mature adipocyte-derived preadipocyte cell line, can be induced to trans-differentiate into osteoblasts in vitro and in vivo. All-trans retinoic acid (RA) induced expression of osteoblast-specific mRNAs encoding Cbfa1/Runx2, osterix, alkaline phosphatase, osteopontin, parathyroid hormone receptor, and osteocalcin in the DFAT cells, but did not induce the expression of adipocyte-specific mRNAs encoding PPARgamma2, C/EBPalpha, and GLUT4. Moreover, alkaline phosphatase activity was expressed in DFAT cells and the cells underwent mineralization of the bone matrix in vitro. Furthermore, when DFAT cells were transplanted subcutaneously into C57BL/6N mice in diffusion chambers, these cells formed ectopic osteoid tissue without any host cell-invasion of the chambers. These results indicate that DFAT cells derived from mature adipocytes can be converted into fully differentiated osteoblasts in vitro and in vivo using RA. DFAT cells provide a unique model for studying the lineage commitment of the adipocytes and osteoblasts derived from mesenchymal stem cells. Identification of the pathways that regulate these processes could lead to the development of new therapeutic strategies for control of unwarranted growth of bone and adipose tissue.

  16. Transient dilated cardiomyopathy in a newborn exposed to idarubicin and all-trans-retinoic acid (ATRA) early in the second trimester of pregnancy.

    Science.gov (United States)

    Siu, B L; Alonzo, M R; Vargo, T A; Fenrich, A L

    2002-01-01

    Acute promyelocytic leukemia was diagnosed in a 28-year-old pregnant woman at 13 gestational weeks. She was immediately started on idarubicin and all-trans-retinoic acid (ATRA) and achieved remission after her fourth cycle of treatment. Serial fetal ultrasonograms throughout pregnancy did not reveal any intrauterine growth retardation or other obvious malformations. The mother delivered a term (36.7 gestational weeks), 2720-gram female neonate. The infant was admitted to the intermediate care nursery for observation due to transient mild respiratory distress during the peripartum period. Because of right ventricular hypertrophy on an electrocardiogram, an echocardiogram was performed on the first day of life which showed moderate dilation of the right atrium and right ventricle with mildly depressed function, two small secundum atrial septal defects, and a small patent ductus arteriosus. The neonate remained hemodynamically stable and no arrhythmias were detected. The remainder of the hospital course was uneventful. When reassessed 1-1/2 months later, she was doing well and did not show any signs of congestive heart failure. A repeat echocardiogram at that time demonstrated complete resolution of the right heart enlargement and closure of the ductus arteriosus with persistence of the small and hemodynamically insignificant secundum atrial septal defects.

  17. All- Trans-Retinoic Acid Augments the Histopathological Outcome of Neuroinflammation and Neurodegeneration in Lupus-Prone MRL/lpr Mice.

    Science.gov (United States)

    Theus, Michelle H; Sparks, Joshua B; Liao, Xiaofeng; Ren, Jingjing; Luo, Xin M

    2017-02-01

    Recently, we demonstrated that treatment with all- trans-retinoic acid (tRA) induced a paradoxical effect on immune activation during the development of autoimmune lupus. Here, we further describe its negative effects on mediating neuroinflammation and neurodegeneration. Female MRL/lpr mice were orally administered tRA or VARA (retinol mixed with 10% tRA) from 6 to 14 weeks of age. Both treatments had a significant effect on brain weight, which correlated with histopathological evidence of focal astrogliosis, meningitis, and ventriculitis. Infiltration of CD138- and Iba1-positve immune cells was observed in the third ventricle and meninges of treated mice that co-labeled with ICAM-1, indicating their inflammatory nature. Increased numbers of circulating plasma cells, autoantibodies, and total IgG were also apparent. IgG and C3 complement deposition in these brain regions were also prominent as was focal astrogliosis surrounding the ventricular lining and meninges. Using Fluoro-Jade staining, we further demonstrate that neuroinflammation was accompanied by neurodegeneration in the cortex of treated mice compared with vehicle controls. These findings indicate that vitamin A exposure exacerbates the immunogenic environment of the brain during the onset of systemic autoimmune disease. Vitamin A may therefore compromise the immuno-privileged nature of the central nervous system under a predisposed immunogenic environment.

  18. Severe stomatitis and ileocecal perforation developed after all-trans retinoic acid monotherapy in an HLA-B51-positive patient with acute promyelocytic leukemia.

    Science.gov (United States)

    Kimura, Kenji; Takeuchi, Masahiro; Hasegawa, Nagisa; Togasaki, Emi; Shimizu, Ryoh; Kawajiri, Chika; Muto, Tomoya; Tsukamoto, Shokichi; Takeda, Yusuke; Ohwada, Chikako; Sakaida, Emiko; Sakai, Shio; Mimura, Naoya; Ota, Satoshi; Iseki, Tohru; Nakaseko, Chiaki

    2016-06-01

    A 34-year-old man who had been referred to our hospital was diagnosed with acute promyelocytic leukemia (APL). All-trans retinoic acid (ATRA), oral administration, was initiated. On day 25, he developed fever and respiratory distress with bilateral pulmonary infiltrates, suggesting differentiation syndrome (DS) caused by ATRA. These symptoms showed amelioration after discontinuing ATRA and initiating methylprednisolone. ATRA was re-started on day 29 at half the original dose because of residual APL blasts. The patient subsequently developed fever, severe stomatitis, and oropharyngeal ulcers, which persisted even after discontinuing ATRA. On day 48, he suddenly developed severe abdominal pain with free air, observable on an abdominal X-ray, and underwent emergency ileocecal resection. Pathological examination of the resected ileocecal intestines revealed multiple ulcers and perforations. No leukemic cell infiltration was observed. In this case, only ATRA was administered for APL treatment. These findings suggest that ileocecal ulcerations and perforations, as well as oropharyngeal ulcers, might have been caused by DS or ATRA. Furthermore, DNA typing of the HLA-B locus revealed that the patient had HLA-B51 associated with Behçet's disease. Therefore, hypercytokinemia with DS might have induced Behçet's disease-like symptoms, including stomatitis and ileocecal perforation, complications that are particularly observed in patients with HLA-B51.

  19. The Vitamin A Derivative All-Trans Retinoic Acid Repairs Amyloid-β-Induced Double-Strand Breaks in Neural Cells and in the Murine Neocortex.

    Science.gov (United States)

    Gruz-Gibelli, Emmanuelle; Chessel, Natacha; Allioux, Clélia; Marin, Pascale; Piotton, Françoise; Leuba, Geneviève; Herrmann, François R; Savioz, Armand

    2016-01-01

    The amyloid-β peptide or Aβ is the key player in the amyloid-cascade hypothesis of Alzheimer's disease. Aβ appears to trigger cell death but also production of double-strand breaks (DSBs) in aging and Alzheimer's disease. All-trans retinoic acid (RA), a derivative of vitamin A, was already known for its neuroprotective effects against the amyloid cascade. It diminishes, for instance, the production of Aβ peptides and their oligomerisation. In the present work we investigated the possible implication of RA receptor (RAR) in repair of Aβ-induced DSBs. We demonstrated that RA, as well as RAR agonist Am80, but not AGN 193109 antagonist, repair Aβ-induced DSBs in SH-SY5Y cells and an astrocytic cell line as well as in the murine cortical tissue of young and aged mice. The nonhomologous end joining pathway and the Ataxia Telangiectasia Mutated kinase were shown to be involved in RA-mediated DSBs repair in the SH-SY5Y cells. Our data suggest that RA, besides increasing cell viability in the cortex of young and even of aged mice, might also result in targeted DNA repair of genes important for cell or synaptic maintenance. This phenomenon would remain functional up to a point when Aβ increase and RA decrease probably lead to a pathological state.

  20. Chromosomal localization of a novel retinoic acid induced gene RA28 and the protein distribution of its encoded protein

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Gene RA28 is a retinoic acid induced novel gene isolated in our laboratory previously. All-trans retinoic acid (ATRA) was used to induce lung adenocarcinoma cell line GLC-82, and RA28 was obtained by subtractive hybridization. Green fluorescent protein (GFP) has emerged as a unique tool for examining introcellular phenomena in living cells. GFP possesses an intrinsic fluorescence at 488 nm that does not require other co-factors. In this report, an eukaryotic expression plasmid pEGFP-C1-RA28 was constructed and transfected with parental cell line GLC-82 to analyze protein expression and its distribution in living cells. Moreover, radiation hybrid (RH) technique was used to localize RA28 to the chromosome. The results show that gene RA28 is mapped to the chromosome 19q13.1 region, its encoded protein is distributed on cell membrane. All the results further demonstrate that GFP and RH techniques are accurate, fast, repetitive, and will be powerful methods for investigating the gene and protein localization.

  1. Formation of ion pairing as an alternative to improve encapsulation and anticancer activity of all-trans retinoic acid loaded in solid lipid nanoparticles

    Directory of Open Access Journals (Sweden)

    Carneiro G

    2012-12-01

    findings are in agreement with the data obtained in the evaluation of subdiploid DNA content and cell-cycle analysis, which showed better anticancer activity for BA-RA-loaded SLNs than TA-RA-loaded SLNs and free RA. Taken together, these findings suggest that the BA-RA-loaded SLN formulation is a promising alternative for the intravenous administration of RA in the treatment of cancer.Keywords: solid lipid nanoparticles, all-trans retinoic acid, cancer, treatment, antitumor activity, ion pairing

  2. In vivo pharmacokinetics, biodistribution and antitumor effect of amphiphilic poly(L-amino acids) micelles loaded with a novel all-trans retinoic acid derivative.

    Science.gov (United States)

    Tang, Jihui; Wang, Xinqun; Wang, Ting; Chen, Feihu; Zhou, Jianping

    2014-01-23

    Poly(amino acid)s are well-known as biodegradable and environmentally acceptable materials. In this study, a series of poly(L-aspartic acid)-b-poly(L-phenylalanine) (PAA-PPA) compounds with different degrees of polymerization were used to prepare copolymer micelles for a poorly water-soluble drug 4-amino-2-trifluoromethyl-phenyl retinate (ATPR, a novel all-trans retinoic acid derivative) and in vivo pharmacokinetics, biodistribution and antitumor efficacy of ATPR delivered by PAA-PPA micelles were evaluated. The area under the plasma concentration time curve AUC0→∞ of ATPR-loaded PAA20PPA20 micelles was 2.23 and 1.97 times higher than that of ATPR solution and ATPR CrmEL solution, respectively; In addition, the mean residence time (MRT) was increased 1.67 and 1.97-fold, respectively and the total body clearance (CL) was reduced 2.25 and 1.98-fold, respectively. The biodistribution study indicated that most of the ATPR in the ATPR-M group was distributed in the liver and there was delayed liver aggregation compared with the ATPR solution and ATPR CrmEL solution groups. Furthermore, the antitumor efficacy of ATPR-loaded PAA20PPA20 micelles was demonstrated in in vivo antitumor models involving mice inoculated with the human gastric cancer cell line SGC-7901. At the same dose of 7mg/kg, the ATPR-loaded micelles group demonstrated a better tumor growth inhibition and induced differentiation than the groups given ATPR solution and ATPR CrmEL solution. Therefore, the ATPR-loaded PAA-PPA micelles appear to be a potentially useful drug delivery system for ATPR and suitable for the chemotherapy of gastric cancer.

  3. All-trans-retinoic Acid Modulates the Plasticity and Inhibits the Motility of Breast Cancer Cells: ROLE OF NOTCH1 AND TRANSFORMING GROWTH FACTOR (TGFβ).

    Science.gov (United States)

    Zanetti, Adriana; Affatato, Roberta; Centritto, Floriana; Fratelli, Maddalena; Kurosaki, Mami; Barzago, Maria Monica; Bolis, Marco; Terao, Mineko; Garattini, Enrico; Paroni, Gabriela

    2015-07-17

    All-trans-retinoic acid (ATRA) is a natural compound proposed for the treatment/chemoprevention of breast cancer. Increasing evidence indicates that aberrant regulation of epithelial-to-mesenchymal transition (EMT) is a determinant of the cancer cell invasive and metastatic behavior. The effects of ATRA on EMT are largely unknown. In HER2-positive SKBR3 and UACC812 cells, showing co-amplification of the ERBB2 and RARA genes, ATRA activates a RARα-dependent epithelial differentiation program. In SKBR3 cells, this causes the formation/reorganization of adherens and tight junctions. Epithelial differentiation and augmented cell-cell contacts underlie the anti-migratory action exerted by the retinoid in cells exposed to the EMT-inducing factors EGF and heregulin-β1. Down-regulation of NOTCH1, an emerging EMT modulator, is involved in the inhibition of motility by ATRA. Indeed, the retinoid blocks NOTCH1 up-regulation by EGF and/or heregulin-β1. Pharmacological inhibition of γ-secretase and NOTCH1 processing also abrogates SKBR3 cell migration. Stimulation of TGFβ contributes to the anti-migratory effect of ATRA. The retinoid switches TGFβ from an EMT-inducing and pro-migratory determinant to an anti-migratory mediator. Inhibition of the NOTCH1 pathway not only plays a role in the anti-migratory action of ATRA; it is relevant also for the anti-proliferative activity of the retinoid in HCC1599 breast cancer cells, which are addicted to NOTCH1 for growth/viability. This effect is enhanced by the combination of ATRA and the γ-secretase inhibitor N-(N-(3,5-difluorophenacetyl)-l-alanyl)-S-phenylglycine t-butyl ester, supporting the concept that the two compounds act at the transcriptional and post-translational levels along the NOTCH1 pathway.

  4. PEG-PLA diblock copolymer micelle-like nanoparticles as all-trans-retinoic acid carrier: in vitro and in vivo characterizations

    Science.gov (United States)

    Li, Yuan; Qi, Xian Rong; Maitani, Yoshie; Nagai, Tsuneji

    2009-02-01

    The purpose of this study was to characterize the properties in vitro, i.e. release, degradation, hemolytic potential and anticancer activity, and in vivo disposition of all-trans-retinoic acid (ATRA) in rats after administration of ATRA-loaded micelle-like nanoparticles. The amphiphilic block copolymers consisted of a micellar shell-forming mPEG block and a core-forming PLA block. The mPEG-PLA nanoparticles prepared by an acetone volatilization dialysis procedure were identified as having core-shell structure by 1H NMR spectroscopy. Critical association concentration, drug contents, loading efficiency, particle size and ξ potential were evaluated. The release of ATRA from the nanoparticles and the degradation of PLA were found to be mostly associated with the compositions of the nanoparticles. ATRA release was faster at smaller molecular weight of copolymer and lower drug contents. In vitro, the incorporation of ATRA in mPEG-PLA nanoparticles reduced the hemolytic potential of ATRA. Furthermore, anticancer activity of ATRA against HepG2 cell was increased by encapsulation, which showed an enhancement of tumor treatment of ATRA. In vivo, after intravenous injection to rats, the levels of ATRA in the blood stream and the bioavailability were higher for ATRA-loaded mPEG-PLA nanoparticles than those for ATRA solution. In conclusion, the structure of the mPEG-PLA diblock copolymer could be modulated to fit the demand of in vitro and in vivo characterizations of nanoparticles. The mPEG-PLA nanoparticles' loading ATRA have a promising future for injection administration.

  5. Apoptosis of Glioblastoma U251 Cells Induced by Carmustine Combined All-trans Retinoic Acid via Regulating Cyclin E and p27kip 1

    Institute of Scientific and Technical Information of China (English)

    QI Bin; WEIJun; HU Guo-zhang; YANG Hong-fa; BI Chun-hua; SUN Zhi-gang; TIAN Yu

    2011-01-01

    The effect and mechanism of carmustine(BCNU) combined with all-trans retinoic acid(ATRA) on the apoptosis of human glioblastoma U251 cells were investigated by means of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay,flow cytometry,reverse transcription-polymerase chain reaction(RT-PCR) and Western blot analysis.The results show that BCNU or ATRA shows time- and dose-dependent inhibition effects on human glioblastoma U251 cells and the combination of BCNU with ATRA shows an synergistic inhibition effect on human glioblastoma U251 cells,and the combined BCNU and ATRA can significantly inhibit the proliferation of human glioblastoma U251 cells,and induce the apoptosis of them,making the cells arrest in the stage of G1 phase,the stage of S and G2 phases decline,the rate of the apoptosis of human glioblastoma U251 cells increase,the corresponding mRNA expression of cyclin E and cyclin-dependent kinase 2(CDK2) downregulated and the corresponding mRNA expression of p27kip 1 unregulated.In addition,the combined BCNU and ATRA reduced the protein expression of nuclear factor kappa B(NF-kB).Taken together,these results suggest that the treatment of human glioblastoma U251 cells with a combination application of ATRA and BCNU can exert synergistic effect,the course of this kind of combination chemotherapy may likely be associated with multiple molecular mechanisms for apoptosis,furthermore,the cyclin E and p27kip 1 should be considered as novel targets for controlling the growth of glioblastoma cells.

  6. Regulatory CD8{sup +} T cells induced by exposure to all-trans retinoic acid and TGF-{beta} suppress autoimmune diabetes

    Energy Technology Data Exchange (ETDEWEB)

    Kishi, Minoru [Department of Internal and Geriatric Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017 (Japan); Yasuda, Hisafumi, E-mail: yasuda@med.kobe-u.ac.jp [Department of Internal and Geriatric Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017 (Japan); Abe, Yasuhisa; Sasaki, Hirotomo; Shimizu, Mami; Arai, Takashi; Okumachi, Yasuyo; Moriyama, Hiroaki; Hara, Kenta; Yokono, Koichi; Nagata, Masao [Department of Internal and Geriatric Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017 (Japan)

    2010-03-26

    Antigen-specific regulatory CD4{sup +} T cells have been described but there are few reports on regulatory CD8{sup +} T cells. We generated islet-specific glucose-6-phosphatase catalytic subunit-related protein (IGRP)-specific regulatory CD8{sup +} T cells from 8.3-NOD transgenic mice. CD8{sup +} T cells from 8.3-NOD splenocytes were cultured with IGRP, splenic dendritic cells (SpDCs), TGF-{beta}, and all-trans retinoic acid (ATRA) for 5 days. CD8{sup +} T cells cultured with either IGRP alone or IGRP and SpDCs in the absence of TGF-{beta} and ATRA had low Foxp3{sup +} expression (1.7 {+-} 0.9% and 3.2 {+-} 4.5%, respectively). In contrast, CD8{sup +} T cells induced by exposure to IGRP, SpDCs, TGF-{beta}, and ATRA showed the highest expression of Foxp3{sup +} in IGRP-reactive CD8{sup +} T cells (36.1 {+-} 10.6%), which was approximately 40-fold increase compared with that before induction culture. CD25 expression on CD8{sup +} T cells cultured with IGRP, SpDCs, TGF-{beta}, and ATRA was only 7.42%, whereas CD103 expression was greater than 90%. These CD8{sup +} T cells suppressed the proliferation of diabetogenic CD8{sup +} T cells from 8.3-NOD splenocytes in vitro and completely prevented diabetes onset in NOD-scid mice in cotransfer experiments with diabetogenic splenocytes from NOD mice in vivo. Here we show that exposure to ATRA and TGF-{beta} induces CD8{sup +}Foxp3{sup +} T cells ex vivo, which suppress diabetogenic T cells in vitro and in vivo.

  7. Combination chemotherapy of doxorubicin, all-trans retinoic acid and low molecular weight heparin based on self-assembled multi-functional polymeric nanoparticles

    Science.gov (United States)

    Zhang, Ting; Xiong, Hui; Zohra Dahmani, Fatima; Sun, Li; Li, Yuanke; Yao, Li; Zhou, Jianping; Yao, Jing

    2015-04-01

    Based on the complementary effects of doxorubicin (DOX), all-trans retinoic acid (ATRA) and low molecular weight heparin (LMWH), the combination therapy of DOX, ATRA and LMWH was expected to exert the enhanced anti-tumor effects and reduce the side effects. In this study, amphiphilic LMWH-ATRA conjugate was synthesized for encapsulating the DOX. In this way, DOX, ATRA and LMWH were assembled into a single nano-system by both chemical and physical modes to obtain a novel anti-tumor targeting drug delivery system that can realize the simultaneous delivery of multiple drugs with different properties to the tumor. LMWH-ATRA nanoparticles exhibited good loading capacities for DOX with excellent physico-chemical properties, good biocompatibility, and good differentiation-inducing activity and antiangiogenic activity. The drug-loading capacity was up to 18.7% with an entrapment efficiency of 78.8%. It was also found that DOX-loaded LMWH-ATRA nanoparticles (DHR nanoparticles) could be efficiently taken up by tumor cells via endocytic pathway, and mainly distributed in cytoplasm at first, then transferred into cell nucleus. Cell viability assays suggested that DHR nanoparticles maintained the cytotoxicity effect of DOX on MCF-7 cells. Moreover, the in vivo imaging analysis indicated that DiR-loaded LMWH-ATRA nanoparticles could target the tumor more effectively as compared to free DiR. Furthermore, DHR nanoparticles possessed much higher anticancer activity and reduced side effects compared to free drugs solution. These results suggested that DHR nanoparticles could be considered as a promising targeted delivery system for combination cancer chemotherapy with lower adverse effects.

  8. Nucleoside transporter expression and activity is regulated during granulocytic differentiation of NB4 cells in response to all-trans-retinoic acid.

    Science.gov (United States)

    Flanagan, Sheryl A; Meckling, Kelly A

    2007-07-01

    NB4 cells express multiple nucleoside transporters (NTs), including: hENT1 (es), and hENT2 (ei), and the CNT subtype referred to as, csg; a concentrative sensitive guanosine specific transporter. csg activity is a distinguishing feature of the NB4 cell line and its presence suggests a particular requirement of these cells for guanosine salvage. Proliferation and differentiation pathways determine, in part, the number of NTs in cells and tissues. In this study, all-trans-retinoic acid (ATRA)-induced granulocytic differentiation of NB4 cells resulted in biphasic changes in guanosine transport. Transient increases in csg and es activity, the result of an increase in V(max) (pmol/muls) of both transporter systems, served as early markers of differentiation while expression of a fully differentiated phenotype was accompanied by a selective loss of csg activity and the return of es activity to that of proliferating cells. Intracellular incorporation of [(3)H]-guanosine decreased as cells matured despite increased transport rates and suggested a reduced intracellular requirement of NB4-granulocytes compared to their proliferating counterparts. Whether a loss of csg activity could serve to assess clinical response to differentiation therapies is not known. Nitrobenzylthioinosine (NBMPR) binding sites within nuclear membrane (NM) preparations, suggested the presence of functional intracellular NTs. An increase in plasma membrane (PM) associated transporters coincided with the early increase in guanosine transport and a decrease in NBMPR binding to NM fractions and suggests that intracellular NTs may serve as a reserve pool for translocation to the (PM) when additional transport capacity is required. The modulation of transporters during differentiation could potentially regulate drug bioavailability and cytotoxicity and should be evaluated prior to combining differentiating agents with traditional nucleoside analogs in the treatment of APL.

  9. Optimization and evalution of all-trans retinoic acid ethosomes%全反式维A酸醇质体的处方优化及评价

    Institute of Scientific and Technical Information of China (English)

    李志; 胡玉容; 郭新红

    2010-01-01

    目的:制备全反式维A酸(all-trans retinoic acid,ATRA)醇质体并对其稳定性及体外经皮渗透等进行考察.方法:采用注入法制备ATRA醇质体,通过正交设计优化制备工艺;同时测定其Zeta电位及粒径;以改进的Franz扩散池法,进行体外小鼠经皮渗透实验,测定药物累积渗透量及透皮速率.结果:优选处方组成为20%乙醇(w/w),4%磷脂(w/w),磷脂:胆固醇(w/w)2:1,磷脂:维A酸(w/w)10:1,检测平均粒径为237.3 nm,Zeta电位为-36.31 mV;ATRA醇质体放置1,10,20 d后,7 h累积透皮量分别为(210.6±1.7),(196.2±3.8)和(181.1±4.2)μg·cm-2,而水醇混合物累积透皮量仅为(120.4±5.4)μg·cm-2.结论:ATRA醇质体制备工艺简单可行,所得传递体粒径较小且均匀,室温放置较稳定,透皮效果较好并可以促进维A酸经皮转运.

  10. Molecular mechanism of inhibitory effects of C-phycocyanin combined with all-trans-retinoic acid on the growth of HeLa cells in vitro.

    Science.gov (United States)

    Yang, Fan; Li, Bing; Chu, Xian-Ming; Lv, Cong-Yi; Xu, Ying-Jie; Yang, Peng

    2014-06-01

    We studied the effects of all-trans-retinoic acid (ATRA), C-phycocyanin (C-PC), or ATRA+C-PC on the growth of cervical cells (HeLa cells), cell cycle distribution, and apoptosis. The anticancer mechanism of the drug combination was revealed. MTT assay was adopted to determine the effects of C-PC and ATRA on the growth of HeLa cells. The expression quantities of cyclin-dependent kinase (CDK) 4, cyclin D1, Bcl-2, caspase-3, and CD59 were determined by in situ hybridization, immunofluorescence, immunohistochemistry staining, Western blot, and RT-PCR. TUNEL assay was adopted to determine the cellular apoptosis levels. Both C-PC and ATRA could inhibit the growth of HeLa cells, and the combination of ATRA+C-PC functioned cooperatively to induce apoptosis in HeLa cells. The dosage of ATRA was reduced when it cooperated with C-PC to reduce the toxicity. ATRA treated with C-PC could induce more cell cycle arrests than the single drug used by decrease in cyclin D1 and CDK4 expression. The combination of the two drugs could upregulate caspase-3 and downregulate the Bcl-2 gene and induce cell apoptosis. Moreover, the combination therapy has an important immunological significance in decreased expression of the CD59 protein. Singly, C-PC or ATRA could inhibit the growth of HeLa cells, and the effects of treatment were further enhanced in the combination group. In combination with C-PC, the dosage of ATRA was effectively reduced. The C-PC + ATRA combination might take effect by inhibiting the progress of the cell cycle, inducing cell apoptosis and promoting complement-mediated cytolysis.

  11. Prediction of in vivo developmental toxicity of all-trans-retinoic acid based on in vitro toxicity data and in silico physiologically based kinetic modeling.

    Science.gov (United States)

    Louisse, Jochem; Bosgra, Sieto; Blaauboer, Bas J; Rietjens, Ivonne M C M; Verwei, Miriam

    2015-07-01

    The use of laboratory animals for toxicity testing in chemical safety assessment meets increasing ethical, economic and legislative constraints. The development, validation and application of reliable alternatives for in vivo toxicity testing are therefore urgently needed. In order to use toxicity data obtained from in vitro assays for risk assessment, in vitro concentration-response data need to be translated into in vivo dose-response data that are needed to obtain points of departure for risk assessment, like a benchmark dose (BMD). In the present study, we translated in vitro concentration-response data of the retinoid all-trans-retinoic acid (ATRA), obtained in the differentiation assay of the embryonic stem cell test, into in vivo dose-response data using a physiologically based kinetic model for rat and human that is mainly based on kinetic model parameter values derived using in vitro techniques. The predicted in vivo dose-response data were used for BMD modeling, and the obtained BMDL10 values [lower limit of the 95 % confidence interval on the BMD at which a benchmark response equivalent to a 10 % effect size (BMR10) is reached (BMD10)] for rat were compared with BMDL10 values derived from in vivo developmental toxicity data in rats reported in the literature. The results show that the BMDL10 values from predicted dose-response data differ about sixfold from the BMDL10 values obtained from in vivo data, pointing at the feasibility of using a combined in vitro-in silico approach for defining a point of departure for toxicological risk assessment.

  12. Modulation of Dishevelled and Vangl2 by All-trans-retinoic Acid in the Developing Mouse Central Nervous System and its Relationship to Teratogenesis

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The response to exposure to all-trans-retinoic acid (RA) during embryogenesis varies from physiologic to severe teratogenic effects and is dependent upon the dose and the stage of development in all species. Vangl2 and Dishevelled genes play key roles in establishing planar cell polarity and regulating convergent extension movements during the neurula period. The effects of RA-mediated teratogenesis might be due to its misregulation of Vangl2 and Dishevelled genes. The aim of this study is to monitor the modulation of Vangl2 and Dishevelled in Kunming mouse embryos following maternal treatment with a single oral dose of 30 mg/(kg body weight) of RA during the neurula period. Exposure of 7.75 d embryos to RA induced characteristic morphological changes. The most obvious external effect was the failure of neural tube closure in the midbrain and forebrain regions in 10 d embryos, resulting in exencephaly in later embryos. RA treatment also led to a pronounced decrease of Vangl2 mRNA at 4 and 18 h and a pronounced increase at 66 h after maternal treatment, as detected by reverse transcription-polymerase chain reaction. Western blot analysis showed a marked decrease of Vangl2 protein at 18 and 42 h and a marked increase at 66 and 90 h after maternal treatment. Dishevelledl/2/3 mRNA was significantly down-regulated at 4 and 18 h and upregulated at 42 h in the fetus after RA treatment, except for an up-regulation of Dishevelled3 at 66 h. The Dishevelled2 mRNA and its protein matched each other. These results hinted that Vangl2 and Dishevelled genes might take part in RA teratogenesis of mouse embryos.

  13. Modulation of Dishevelled and Vangl2 by all-trans-retinoic acid in the developing mouse central nervous system and its relationship to teratogenesis.

    Science.gov (United States)

    Zhang, Yanping; Liu, Kai; Gao, Yingmao; Li, Shaoling

    2007-09-01

    The response to exposure to all-trans-retinoic acid (RA) during embryogenesis varies from physiologic to severe teratogenic effects and is dependent upon the dose and the stage of development in all species. Vangl2 and Dishevelled genes play key roles in establishing planar cell polarity and regulating convergent extension movements during the neurula period. The effects of RA-mediated teratogenesis might be due to its misregulation of Vangl2 and Dishevelled genes. The aim of this study is to monitor the modulation of Vangl2 and Dishevelled in Kunming mouse embryos following maternal treatment with a single oral dose of 30 mg/(kg body weight) of RA during the neurula period. Exposure of 7.75 d embryos to RA induced characteristic morphological changes. The most obvious external effect was the failure of neural tube closure in the midbrain and forebrain regions in 10 d embryos, resulting in exencephaly in later embryos. RA treatment also led to a pronounced decrease of Vangl2 mRNA at 4 and 18 h and a pronounced increase at 66 h after maternal treatment, as detected by reverse transcription-polymerase chain reaction. Western blot analysis showed a marked decrease of Vangl2 protein at 18 and 42 h and a marked increase at 66 and 90 h after maternal treatment. Dishevelled1/2/3 mRNA was significantly down-regulated at 4 and 18 h and up-regulated at 42 h in the fetus after RA treatment, except for an up-regulation of Dishevelled3 at 66 h. The Dishevelled2 mRNA and its protein matched each other. These results hinted that Vangl2 and Dishevelled genes might take part in RA teratogenesis of mouse embryos.

  14. All-trans retinoic acid as adjunct to intensive treatment in younger adult patients with acute myeloid leukemia: results of the randomized AMLSG 07-04 study.

    Science.gov (United States)

    Schlenk, Richard F; Lübbert, Michael; Benner, Axel; Lamparter, Alexander; Krauter, Jürgen; Herr, Wolfgang; Martin, Hans; Salih, Helmut R; Kündgen, Andrea; Horst, Heinz-A; Brossart, Peter; Götze, Katharina; Nachbaur, David; Wattad, Mohammed; Köhne, Claus-Henning; Fiedler, Walter; Bentz, Martin; Wulf, Gerald; Held, Gerhard; Hertenstein, Bernd; Salwender, Hans; Gaidzik, Verena I; Schlegelberger, Brigitte; Weber, Daniela; Döhner, Konstanze; Ganser, Arnold; Döhner, Hartmut

    2016-12-01

    The aim of this clinical trial was to evaluate the impact of all-trans retinoic acid (ATRA) in combination with chemotherapy and to assess the NPM1 status as biomarker for ATRA therapy in younger adult patients (18-60 years) with acute myeloid leukemia (AML). Patients were randomized for intensive chemotherapy with or without open-label ATRA (45 mg/m(2), days 6-8; 15 mg/m(2), days 9-21). Two cycles of induction therapy were followed by risk-adapted consolidation with high-dose cytarabine or allogeneic hematopoietic cell transplantation. Due to the open label character of the study, analysis was performed on an intention-to-treat (ITT) and a per-protocol (PP) basis. One thousand one hundred patients were randomized (556, STANDARD; 544, ATRA) with 38 patients treated vice versa. Median follow-up for survival was 5.2 years. ITT analyses revealed no difference between ATRA and STANDARD for the total cohort and for the subset of NPM1-mutated AML with respect to event-free (EFS; p = 0.93, p = 0.17) and overall survival (OS; p = 0.24 and p = 0.32, respectively). Pre-specified PP analyses revealed better EFS in NPM1-mutated AML (p = 0.05) and better OS in the total cohort (p = 0.03). Explorative subgroup analyses on an ITT basis revealed better OS (p = 0.05) in ATRA for genetic low-risk patients according to ELN recommendations. The clinical trial is registered at clinicaltrialsregister.eu (EudraCT Number: 2004-004321-95).

  15. Complete remission of t(11;17) positive acute promyelocytic leukemia induced by all-trans retinoic acid and granulocyte colony-stimulating factor

    NARCIS (Netherlands)

    J.H. Jansen (Joop); M.C. de Breems-de Ridder (Marleen); W.M. Geertsma; C.A.J. Erpelinck (Claudia); K. van Lom (Kirsten); R. Slater (Rosalyn); B.A. van der Reijden (Bert); G.E. de Greef (Georgine); P. Sonneveld (Pieter); B. Löwenberg (Bob); E.M.E. Smit (Elisabeth)

    1999-01-01

    textabstractThe combined use of retinoic acid and chemotherapy has led to an important improvement of cure rates in acute promyelocytic leukemia. Retinoic acid forces terminal maturation of the malignant cells and this application represents the first generally accepted

  16. Chmp 1A is a mediator of the anti-proliferative effects of All-trans Retinoic Acid in human pancreatic cancer cells

    Directory of Open Access Journals (Sweden)

    Nguyen Hanh

    2009-02-01

    Full Text Available Abstract Background We recently have shown that Charged multivesicular protein/Chromatin modifying protein1A (Chmp1A functions as a tumor suppressor in human pancreatic tumor cells. Pancreatic cancer has the worst prognosis of all cancers with a dismal 5-year survival rate. Preclinical studies using ATRA for treating human pancreatic cancer suggest this compound might be useful for treatment of pancreatic cancer patients. However, the molecular mechanism by which ATRA inhibits growth of pancreatic cancer cells is not clear. The objective of our study was to investigate whether Chmp1A is involved in ATRA-mediated growth inhibition of human pancreatic tumor cells. Results We performed microarray studies using HEK 293T cells and discovered that Chmp1A positively regulated Cellular retinol-binding protein 1 (CRBP-1. CRBP-1 is a key regulator of All-trans retinoic acid (ATRA through ATRA metabolism and nuclear localization. Since our microarray data indicates a potential involvement of Chmp1A in ATRA signaling, we tested this hypothesis by treating pancreatic tumor cells with ATRA in vitro. In the ATRA-responsive cell lines, ATRA significantly increased the protein expression of Chmp1A, CRBP-1, P53 and phospho-P53 at serine 15 and 37 position. We found that knockdown of Chmp1A via shRNA abolished the ATRA-mediated growth inhibition of PanC-1 cells. Also, Chmp1A silencing diminished the increase of Chmp1A, P53 and phospho-P53 protein expression induced by ATRA. In the ATRA non-responsive cells, ATRA did not have any effect on the protein level of Chmp1A and P53. Chmp1A over-expression, however, induced growth inhibition of ATRA non-responsive cells, which was accompanied by an increase of Chmp1A, P53 and phospho-P53. Interestingly, in ATRA responsive cells Chmp1A is localized to the nucleus, which became robust upon ATRA treatment. In the ATRA-non-responsive cells, Chmp1A was mainly translocated to the plasma membrane upon ATRA treatment. Conclusion

  17. Inhibition of fat cell differentiation in 3T3-L1 pre-adipocytes by all-trans retinoic acid: Integrative analysis of transcriptomic and phenotypic data

    Directory of Open Access Journals (Sweden)

    Katharina Stoecker

    2017-03-01

    Full Text Available The process of adipogenesis is controlled in a highly orchestrated manner, including transcriptional and post-transcriptional events. In developing 3T3-L1 pre-adipocytes, this program can be interrupted by all-trans retinoic acid (ATRA. To examine this inhibiting impact by ATRA, we generated large-scale transcriptomic data on the microRNA and mRNA level. Non-coding RNAs such as microRNAs represent a field in RNA turnover, which is very important for understanding the regulation of mRNA gene expression. High throughput mRNA and microRNA expression profiling was performed using mRNA hybridisation microarray technology and multiplexed expression assay for microRNA quantification. After quantitative measurements we merged expression data sets, integrated the results and analysed the molecular regulation of in vitro adipogenesis. For this purpose, we applied local enrichment analysis on the integrative microRNA-mRNA network determined by a linear regression approach. This approach includes the target predictions of TargetScan Mouse 5.2 and 23 pre-selected, significantly regulated microRNAs as well as Affymetrix microarray mRNA data. We found that the cellular lipid metabolism is negatively affected by ATRA. Furthermore, we were able to show that microRNA 27a and/or microRNA 96 are important regulators of gap junction signalling, the rearrangement of the actin cytoskeleton as well as the citric acid cycle, which represent the most affected pathways with regard to inhibitory effects of ATRA in 3T3-L1 preadipocytes. In conclusion, the experimental workflow and the integrative microRNA–mRNA data analysis shown in this study represent a possibility for illustrating interactions in highly orchestrated biological processes. Further the applied global microRNA–mRNA interaction network may also be used for the pre-selection of potential new biomarkers with regard to obesity or for the identification of new pharmaceutical targets.

  18. All-trans retinoic acid promotes TGF-β-induced Tregs via histone modification but not DNA demethylation on Foxp3 gene locus.

    Directory of Open Access Journals (Sweden)

    Ling Lu

    Full Text Available BACKGROUND: It has been documented all-trans retinoic acid (atRA promotes the development of TGF-β-induced CD4(+Foxp3(+ regulatory T cells (iTreg that play a vital role in the prevention of autoimmune responses, however, molecular mechanisms involved remain elusive. Our objective, therefore, was to determine how atRA promotes the differentiation of iTregs. METHODOLOGY/PRINCIPAL FINDINGS: Addition of atRA to naïve CD4(+CD25(- cells stimulated with anti-CD3/CD28 antibodies in the presence of TGF-β not only increased Foxp3(+ iTreg differentiation, but maintained Foxp3 expression through apoptosis inhibition. atRA/TGF-β-treated CD4(+ cells developed complete anergy and displayed increased suppressive activity. Infusion of atRA/TGF-β-treated CD4(+ cells resulted in the greater effects on suppressing symptoms and protecting the survival of chronic GVHD mice with typical lupus-like syndromes than did CD4(+ cells treated with TGF-β alone. atRA did not significantly affect the phosphorylation levels of Smad2/3 and still promoted iTreg differentiation in CD4(+ cells isolated from Smad3 KO and Smad2 conditional KO mice. Conversely, atRA markedly increased ERK1/2 activation, and blockade of ERK1/2 signaling completely abolished the enhanced effects of atRA on Foxp3 expression. Moreover, atRA significantly increased histone methylation and acetylation within the promoter and conserved non-coding DNA sequence (CNS elements at the Foxp3 gene locus and the recruitment of phosphor-RNA polymerase II, while DNA methylation in the CNS3 was not significantly altered. CONCLUSIONS/SIGNIFICANCE: We have identified the cellular and molecular mechanism(s by which atRA promotes the development and maintenance of iTregs. These results will help to enhance the quantity and quality of development of iTregs and may provide novel insights into clinical cell therapy for patients with autoimmune diseases and those needing organ transplantation.

  19. Synergistic effect of all-trans-retinoic acid and arsenic trioxide on growth inhibition and apoptosis in human hepatoma, breast cancer, and lung cancer cells in vitro

    Institute of Scientific and Technical Information of China (English)

    Le-Min Lin; Bao-Xin Li; Jian-Bing Xiao; Dan-Hua Lin; Bao-Feng Yang

    2005-01-01

    AIM: To investigate the effect of all-trans-retinoic acid (ATRA) on arsenic trioxide (As2O3)-induced apoptosis of human hepatoma, breast cancer, and lung cancer cells in an attempt to find a better combination therapy for solid tumors.METHODS: Human hepatoma cell lines HepG2, Hep3B,human breast cancer cell line MCF-7, and human lung adenocarcinoma cell line AGZY-83-a were treated with As2O3 together with ATRA. Cell survival fraction was determined by MTT assay, cell viability and apoptosis were measured by annexin V-fluorescein isothiocyanate (FITC) and PI staining, and intracellular glutathione (GSH)and glutathione-S-transferase (GST) activities were determined using commercial kits.RESULTS: Cytotoxicity of ATRA was low. ATRA (0.1, 1,and 10 μmol/L) could synergistically potentiate As2O3 to exert a dose-dependent inhibition of growth and to induce apoptosis in each of the cell lines. HepG2 and Hep3B with low intracellular GSH or GST activities were remarkably sensitive to As2O3 or As2O3+ATRA, while AGZY-83-a with higher GSH or GST activities was less sensitive to As2O3or As2O3+ATRA. Treatment with 2 μmol/L As2O3 for 72 h significantly decreased intracellular GSH and GST levels in each of the cell lines, and 1 μmol/L ATRA alone reduced minimal intracellular GSH and GST levels. ATRA potentiated the effect of As2O3 on intracellular GSH levels, but intracellular GST levels were not significantly affected by the combination of As2O3 and ATRA for 72 h as compared to As2O3 alone.CONCLUSION: ATRA can strongly potentiate As2O3-induced growth-inhibition and apoptosis in each of the cell lines, and two drugs can produce a significant synergic effect. The sensitivity to As2O3 or As2O3+ATRA is inversely proportional to intracellular GSH or GST levels in each of the cell lines. The GSH redox system may be the possible mechanism by which ATRA synergistically potentiates As2O3 to exert a dose-dependent inhibition of growth and to induce apoptosis.

  20. Therapeutic effect of all-trans-retinoic acid (at-RA on an autoimmune nephritis experimental model: role of the VLA-4 integrin

    Directory of Open Access Journals (Sweden)

    Lucio-Cazaña Javier

    2007-01-01

    Full Text Available Abstract Background Mercuric chloride (HgCl2 induces an autoimmune nephritis in the Brown Norway (BN rats characterized by anti-glomerular basement membrane antibodies (anti-GBM Ab deposition, proteinuria and a severe interstitial nephritis, all evident at day 13 of the disease. We assessed the effects of all-trans retinoic acid (at-RA in this experimental model. At-RA is a vitamin A metabolite which has shown beneficial effects on several nephropathies, even though no clear targets for at-RA were provided. Methods We separated animals in four different experimental groups (HgCl2, HgCl2+at-RA, at-RA and vehicle. From each animal we collected, at days 0 and 13, numerous biological samples: urine, to measure proteinuria by colorimetry; blood to determine VLA-4 expression by flow citometry; renal tissue to study the expression of VCAM-1 by Western blot, the presence of cellular infiltrates by immunohistochemistry, the IgG deposition by immunofluorescence, and the cytokines expression by RT-PCR. Additionally, adhesion assays to VCAM-1 were performed using K562 α4 transfectant cells. ANOVA tests were used for statistical significance estimation. Results We found that at-RA significantly decreased the serum levels of anti-GBM and consequently its deposition along the glomerular membrane. At-RA markedly reduced proteinuria as well as the number of cellular infiltrates in the renal interstitium, the levels of TNF-α and IL-1β cytokines and VCAM-1 expression in renal tissue. Moreover, we reported here for the first time in an in vivo model that at-RA reduced, to basal levels, the expression of VLA-4 (α4β1 integrin induced by mercury on peripheral blood leukocytes (PBLs. In addition, using K562 α4 stable transfectant cells, we found that at-RA inhibited VLA-4 dependent cell adhesion to VCAM-1. Conclusion Here we demonstrate a therapeutic effect of at-RA on an autoimmune experimental nephritis model in rats. We report a significant reduction of the

  1. AIDA (all-trans retinoic acid + idarubicin) in newly diagnosed acute promyelocytic leukemia: a Gruppo Italiano Malattie Ematologiche Maligne dell'Adulto (GIMEMA) pilot study.

    Science.gov (United States)

    Avvisati, G; Lo Coco, F; Diverio, D; Falda, M; Ferrara, F; Lazzarino, M; Russo, D; Petti, M C; Mandelli, F

    1996-08-15

    From March 1993 to October 1993, 20 consecutive, newly diagnosed acute promyelocytic leukemia (APL) patients from 13 Italian institutions entered in a pilot study named AIDA, combining all-trans retinoic acid (ATRA) with idarubicin (IDA). ATRA was administered orally beginning on the first day of induction at the dosage of 45 mg/m2/d until complete remission (CR), whereas IDA was administered intravenously at the dosage of 12 mg/m2/d on days 2, 4, 6, and 8 of the induction. Patients who achieved CR were consolidated with 3 courses of chemotherapy without ATRA; thereafter, they were followed up for molecular and hematologic CR. The median age was 35.3 years (range, 6.5 to 67.6 years); 8 patients were males and 12 females; 4 had the hypogranular variant of APL (M3v), and 4 (2 with M3v) presented with leukocyte counts > or = 10,000/microL. Molecular analysis for the promyelocytic leukemia-retinoic acid receptor alpha (PML-RAR alpha) hybrid gene at diagnosis was performed in 16 patients by means of reverse transcription-polymerase chain reaction (RT-PCR) analysis, and all were RT-PCR+ for the hybrid gene. In the remaining 4 patients, the cytogenetic study showed the presence of the t(15;17). After a median time of 36 days (range, 28 to 52 days) 18 (90%) patients achieved CR; the remaining 2 patients died 12 and 34 days after diagnosis from myocardial infarction caused by fungal myocarditis and from massive hemoptysis, respectively. ATRA syndrome was observed in only 2 patients, and, after the prompt discontinuation of ATRA and initiation of dexamethasone, both recovered from the syndrome. However, after recovering, 1 patient achieved CR, whereas the other died at day 34 because of massive hemoptysis; other side effects were very limited. At recovery from the third consolidation course, only 3 of 14 (21.4%) tested patients were RT-PCR+ for the PML-RAR alpha hybrid gene. Of these, 2 relapsed shortly afterwards; however, in the last patient, the PML-RAR alpha disappeared

  2. Prognostic value of FLT3 mutations in patients with acute promyelocytic leukemia treated with all-trans retinoic acid and anthracycline monochemotherapy

    NARCIS (Netherlands)

    P. Montesinos (Pau); M. González (Marcos); F. Manso (Félix); E. Vellenga (Edo); B. Löwenberg (Bob); M.A. Sanz (Miguel Angel)

    2011-01-01

    textabstractBackground Fms-like tyrosine kinase-3 (FLT3) gene mutations are frequent in acute promyelocytic leukemia but their prognostic value is not well established. Design and Methods We evaluated FLT3-internal tandem duplication and FLT3-D835 mutations in patients treated with all-trans retinoi

  3. Altered expression of retinoic acid (RA) receptor mRNAs in the fetal mouse secondary palate by all-trans and 13-cis RAs: implications for RA-induced teratogenesis.

    Science.gov (United States)

    Naitoh, H; Mori, C; Nishimura, Y; Shiota, K

    1998-01-01

    Retinoic acid (RA) is mandatory for various biological processes and normal embryonic development but is teratogenic at high concentrations. In rodents, one of the major malformations induced by RA is cleft palate (CP). RA mediates its effects by RA receptors (RARs), but the expression patterns of RARs in the developing palate are still unclear. We investigated the normal expression of RAR alpha, beta, and gamma messenger RNAs (mRNAs) in the fetal mouse secondary palate and the effects of all-trans and 13-cis RAs on the expression of RAR mRNAs by Northern blot analysis. RAR alpha (2.8, 3.8 kb), RAR beta (3.3 kb), and RAR gamma (3.7 kb) mRNAs were detected in the fetal palate on gestational days (GD) 12.5-14.5. The expression of RAR alpha and gamma mRNAs did not show apparent sequential changes, but that of RAR beta mRNA increased at GD 13.5. Treatment of pregnant mice with 100 mg/kg all-trans RA induced CP in 94% of the fetuses and elevated the levels of RAR beta and gamma mRNAs in the fetal palate. The up-regulation of RAR beta mRNA by all-trans RA was more marked than that of RAR gamma mRNA. Treatment with 100 mg/kg 13-cis RA induced CP in only 19% of the fetuses. Although 13-cis RA elevated the RAR beta and gamma mRNA levels in fetal palates, its up-regulation was slower and less marked than that induced by all-trans RA. These findings indicate that the induction of RAR beta mRNA in the fetal palate correlates well with the tissue concentration of all-trans RA after RA treatment, and RAR beta may be one of the most influential candidate molecules for RA-induced teratogenesis.

  4. Effect of Tanshitone on prevention and treatment of retinoic acid-induced osteoporosis in mice

    Institute of Scientific and Technical Information of China (English)

    ZHOU Yan-meng; LIU Yu-bo; GAO Yun-sheng

    2008-01-01

    Objective To observe the prevention and therapeutic effects of tanshitone (TAN) on retinoic acid induced osteoporosis in mice. Methods The mice osteoporosis was induced by given retinoic acid intragasttrically for two weeks. The histomorphological features of bone were observed and biochemical indexes in serum (Ca, P, ALP, TRAP, E2, BGP) were determined after mice were given TAN at the dose of 40, 80, 160 mg·kg-1 respectively. Results Tanshitone can induce high conversion of osteoporosis. The levels of P, ALP, TRAP and BGP in the TAN groups were lower than the model group, while the E2 level was higher than the model group. Conclusions Tanshitone can prevent the loss bone in the experimental mice. The mechanism may be that it improves the level of estrogenic hormone and inhibits the high bone turnover.

  5. Influence of suppressor gene p16 on retinoic acid inducing cancer cell A549 differentiation

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective To investigate the role of suppressor gene p16 in the process of differential regulation of retinoic acid (RA) on the A549 lung cancer cells.Methods Tumor suppressor gene p16 was transferred into A549 cells and the cells were treated with all-trans retinoic acid (ATR) at the dosage of 5×10-6 mol/L for 4 d. After that, the proliferation and differentiation of A549 cells were examined by growth curve and cytometry analysis, the change of lung lineage-specific marker MUC1 was tested by immunohistochemical staining. Meanwhile, Western blot was used to observe the change of p16 protein expression in A549 cells treated with ATRA.Results ATRA could obviously inhibit the growth and induce the differentiation of A549 Cells that were transferred with p16 gene. There were more cells arrested in G1/G0 phase and the expression of MUG1 was markedly down-regulated than in control cells. The expression of p16 protein was up-regulated in A549 cells treated with ATRA.Conclusion Suppressor gene p16 could enhance the effects of RA and proliferated suppression and differential induction of A549 cells.

  6. Acute Coronary Syndrome Manifesting as an Adverse Effect of All-trans-Retinoic Acid in Acute Promyelocytic Leukemia: A Case Report with Review of the Literature and a Spotlight on Management

    Directory of Open Access Journals (Sweden)

    K. Govind Babu

    2016-01-01

    Full Text Available Background. Acute promyelocytic leukemia is characterized by t(15;17. This leads to the formation of PML/RARα which blocks the differentiation of blasts at the stage of promyelocytes. This is reversed by all-trans-retinoic acid (ATRA, a vitamin A derivative. Acute myocardial ischemia is a rare side effect of ATRA. Case Report. We report a case of acute coronary syndrome manifesting as an adverse effect of ATRA in a lady with APL who had no other risk factors for cardiovascular disease. Conclusions. We emphasize the need for high index of suspicion for the diagnosis of this entity. In the light of this case, the rare instances of ATRA associated acute myocardial ischemia recorded in the literature and the options available for treatment of acute promyelocytic leukemia sans ATRA have been reviewed.

  7. Morphogenetic and neuronal characterization of human neuroblastoma multicellular spheroids cultured under undifferentiated and all-trans-retinoic acid-differentiated conditions

    Directory of Open Access Journals (Sweden)

    Gwon-Soo Jung

    2013-05-01

    Full Text Available In this study, we aimed to compare the morphogenetic andneuronal characteristics between monolayer cells andspheroids. For this purpose, we established spheroid formationby growing SH-SY5Y cells on the hydrophobic surfaces ofthermally-collapsed elastin-like polypeptide. After 4 days ofculture, the relative proliferation of the cells within spheroidswas approximately 92% of the values for monolayer cultures.As measured by quantitative assays for mRNA and proteinexpressions, the production of synaptophysin and neuronspecificenolase (NSE as well as the contents of cell adhesionmolecules (CAMs and extracellular matrix (ECM proteins aremuch higher in spheroids than in monolayer cells. Under theall-trans-retinoic acid (RA-induced differentiation condition,spheroids extended neurites and further up-regulated theexpression of synaptophysin, NSE, CAMs, and ECM proteins.Our data indicate that RA-differentiated SH-SY5Y neurospheroidsare functionally matured neuronal architectures. [BMBReports 2013; 46(5: 276-281

  8. ISOLATION AND IDENTIFICATION OF cDNA FRAGMENTS AND FULL-LENGTH cDNA DIFFERENTIALLY EXPRESSED IN HUMAN GLIOBLASTOMA CELL LINE BT-325 VERSUS ALL-TRANS RETINOIC ACID INDUCTION

    Institute of Scientific and Technical Information of China (English)

    金虎林; 胡松年; 李光涛; 涂纯; 袁建刚; 强伯勤

    2000-01-01

    Objective. To investigate the differentiation process of the human glioblastoma cells. Methods. Differential display reverse transcribed-PCR(DDRT-PCR) was used to isolate the genes differentially expressed in control and all-trans retinoic acid treated human glioblastoma cell line BT-325. Routine method of cDNA library screening was performed to clone full-length cDNA. Results. Thirty-six RT-PCR reactions were performed and 64 differentially expressed fragments were recovered, amplified and cloned. Of them,46 ESTs were sequenced and delivered into the GenBank. The homology comparison us ing BLAST algorithm revealed that 22ESTs are highly homologous with the known genes and many of them play impor tant roles in the cell differentiation progress. A dot-blot hybridization was conducted to certify the differentiation expres sion. The result showed that 27 EST clones are expressed at different level in control and all-trans retinoi c acid treated BT-325 cells. A full-length cDNA was cloned using the ES T-HGBB098. Conclusion. DDRT-PCR was a simple and effective method to serially analyze the differentially expressed genes.

  9. ISOLATION AND IDENTIFICATION OF cDNA FRAGMENTS AND FULL-LENGTH cDNA DIFFERENTIALLY EXPRESSEDIN HUMAN GLIOBLASTOMA CELL LINE BT-325 VERSUS ALL-TRANS RETINOIC ACID INDUCTION

    Institute of Scientific and Technical Information of China (English)

    金虎林; 胡松年; 李光涛; 涂纯; 袁建刚; 强伯勤

    2000-01-01

    Objective. To investigate the differentiation process of the human glioblastoma cells. Methods. Differential display reverse transcribed-PCR(DDRT-PCR) was used to isolate the genes differentially expressed in control and all-trans retinoic acid treated human glioblastoma cell line BT-325. Routine method of cDNA library screening was performed to clone full-length cDNA. Results. Thirty-six RT-PCR reactions were performed and 64 differentially expressed fragments were recovered, amplified and cloned. Of them,46 ESTs were sequenced and delivered into the GenBank. The homology comparison us-ing BLAST algorithm revealed that 22ESFs are highly homologous with the known genes and many of them play impor-tant roles in the cell differentiation progress. A dot-blot hybridization was conducted to certify the differemiation expres-sion. The result showed that 27 EST clones are expressed at different level in control and all-traus retinoic acid treated BT-325 cells. A full-length cDNA was cloned using the EST-HGBB098.Conclusion. DDRT-PCR was a simple and effective method to segally analyze the differentially expressed genes.

  10. Gene expression in retinoic acid-induced neural tube defects A cDNA mieroarray analysis

    Institute of Scientific and Technical Information of China (English)

    Xiaodong Long; Zhong Yang; Yi Zeng; Hongli Li; Yangyun Han; Chao You

    2009-01-01

    the cranium and abnormal changes of the metencephalon and face.cDNA microarray analysis suggested that the changes in expression of seven different genes were similar on both days E10.5 and E11.5. These were downregulation of NekT, Igfbp5, Zw10,Csf3r, Psmc6 and Rbl, and upregulation of Apoa-4. This study also indicated that Cdk5 expression was downregulated in the retinoic acid group on day E11.5. The results of the cDNA microarray analysis were partly confirmed by Northern blotting.CONCLUSION: Cdk5, NekT, Igfbp5, ZwlO, Csf3r, Psmc6, Rb 1 and Apoa-4 may be key factors in retinoic acid-induced neural tube defects.

  11. Effects of varied interferons in combination with all-trans retinoic acid (ATRA) on proliferation and differentiation of ATRA-resistent APL cell

    Institute of Scientific and Technical Information of China (English)

    HE Peng-cheng; ZHANG Mei; LI Jing; CAI Rui-bo; LIU Ya-lin; CAO Yun-xin

    2006-01-01

    Objective:To investigate the effects and mechanisms of interferon in combination with alltrans retinoic acid (ATRA) on proliferation and differentiation of ATRA-resistent APL cell. Methods :After MR2 cells (ATRA-resistance cell line) were treated with IFN-α, IFN-γ and ATRA alone or IFN-α and IFN-γ in combination with ATRA respectively. The cell roliferation was tested by MTT test and the cell differentiation was tested through light microscope by NBT test and flow cytometry (FCM). The expression of promyelocytic leukemia (PML) protein was observed by indirect immune fluorescent method. Results: Both IFN-α and IFN-γ could inhibit the proliferation and induce the differentiation of MR2 cells to some extent. The effects were more obvious after both interferons in combination with ATRA respectively (P<0. 05). Moreover, the maturation of MR2 cells induced by IFN-γ+ATRA group was more higher than that by IFN-α+ATRA group (P<0.05). Both interferons could induce the expressions of PML protein. Conclusion :Both interferons can inhibit MR2 cells proliferation, which may be related to the expression of PML protein induced by both interferons. The inducing differentiation effects of IFN-γ+ATRA group on MR2 cells are more powerful than those of IFN-α+ATRA group, which may be related to the different signal transduction pathway of both interferons.

  12. Retinoic acid induces nuclear accumulation of Raf1 during differentiation of HL-60 cells.

    Science.gov (United States)

    Smith, James; Bunaciu, Rodica P; Reiterer, Gudrun; Coder, David; George, Thaddeus; Asaly, Michael; Yen, Andrew

    2009-08-01

    All trans-retinoic acid (RA) is a standard therapeutic agent used in differentiation induction therapy treatment of acute promyelocytic leukemia (APL). RA and its metabolites use a diverse set of signal transduction pathways during the differentiation program. In addition to the direct transcriptional targets of the nuclear RAR and RXR receptors, signals derived from membrane receptors and the Raf-MEK-ERK pathway are required. Raf1 phosphorylation and the prolonged activation of Raf1 persisting during the entire differentiation process are required for RA-dependent differentiation of HL-60 cells. Here we identify a nuclear redistribution of Raf1 during the RA-induced differentiation of HL-60 cells. In addition, the nuclear accumulation of Raf1 correlates with an increase in Raf1 phosphorylated at serine 621. The serine 621 phosphorylated Raf1 is predominantly localized in the nucleus. The RA-dependent nuclear accumulation of Raf1 suggests a novel nuclear role for Raf1 during the differentiation process.

  13. Retinoic acid induces nuclear accumulation of Raf1 during differentiation of HL-60 cells

    Energy Technology Data Exchange (ETDEWEB)

    Smith, James; Bunaciu, Rodica P.; Reiterer, Gudrun [Department of Biomedical Sciences, T4-008 VRT, Cornell University, Ithaca, NY 14853 (United States); Coder, David; George, Thaddeus [Amnis Corporation, Seattle, Washington (United States); Asaly, Michael [Department of Biomedical Sciences, T4-008 VRT, Cornell University, Ithaca, NY 14853 (United States); Yen, Andrew, E-mail: ay13@cornell.edu [Department of Biomedical Sciences, T4-008 VRT, Cornell University, Ithaca, NY 14853 (United States)

    2009-08-01

    All trans-retinoic acid (RA) is a standard therapeutic agent used in differentiation induction therapy treatment of acute promyelocytic leukemia (APL). RA and its metabolites use a diverse set of signal transduction pathways during the differentiation program. In addition to the direct transcriptional targets of the nuclear RAR and RXR receptors, signals derived from membrane receptors and the Raf-MEK-ERK pathway are required. Raf1 phosphorylation and the prolonged activation of Raf1 persisting during the entire differentiation process are required for RA-dependent differentiation of HL-60 cells. Here we identify a nuclear redistribution of Raf1 during the RA-induced differentiation of HL-60 cells. In addition, the nuclear accumulation of Raf1 correlates with an increase in Raf1 phosphorylated at serine 621. The serine 621 phosphorylated Raf1 is predominantly localized in the nucleus. The RA-dependent nuclear accumulation of Raf1 suggests a novel nuclear role for Raf1 during the differentiation process.

  14. Molecular cloning and characterization of two novel retinoic acid-inducible orphan G-protein-coupled receptors (GPRC5B and GPRC5C).

    Science.gov (United States)

    Robbins, M J; Michalovich, D; Hill, J; Calver, A R; Medhurst, A D; Gloger, I; Sims, M; Middlemiss, D N; Pangalos, M N

    2000-07-01

    Using homology searching of public databases with a metabotropic glutamate receptor sequence from Caenorhabditis elegans, two novel protein sequences (named RAIG-2 (HGMW-approved symbol GPRC5B) and RAIG-3 (HGMW-approved symbol GPRC5C) were identified containing seven putative transmembrane domains characteristic of G-protein-coupled receptors (GPCRs). RAIG-2 and RAIG-3 encode open reading frames of 403 and 442 amino acid polypeptides, respectively, and show 58% similarity to the recently identified retinoic acid-inducible gene-1 (RAIG-1, HGMW-approved symbol RAI3). Analysis of the three protein sequences places them within the type 3 GPCR family, which includes metabotropic glutamate receptors, GABA(B) receptors, calcium-sensing receptors, and pheromone receptors. However, in contrast to other type 3 GPCRs, RAIG-1, RAIG-2, and RAIG-3 have only short N-terminal domains. RAIG-2 and RAIG-3 cDNA sequences were cloned into the mammalian expression vector pcDNA3 with c-myc or HA epitope tags inserted at their N-termini, respectively. Transient transfection experiments in HEK239T cells using these constructs demonstrated RAIG-2 and RAIG-3 expression at the cell surface. Distribution profiles of mRNA expression obtained by semiquantitative Taq-Man PCR analysis showed RAIG-2 to be predominantly expressed in human brain areas and RAIG-3 to be predominantly expressed in peripheral tissues. In addition, expression of RAIG-2 and RAIG-3 mRNA was increased following treatment with all-trans-retinoic acid in a manner similar to that previously described for RAIG-1. Finally, RAIG-2 was mapped to chromosome 16p12 (D16S405-D16S3045) and RAIG-3 to chromosome 17q25 (D17S1352-D17S785). These results suggest that RAIG-1, RAIG-2, and RAIG-3 represent a novel family of retinoic acid-inducible receptors, most closely related to the type 3 GPCR subfamily, and provide further evidence for a linkage between retinoic acid and G-protein-coupled receptor signal transduction pathways.

  15. Rotavirus nonstructural protein 1 antagonizes innate immune response by interacting with retinoic acid inducible gene I

    Directory of Open Access Journals (Sweden)

    Qin Lan

    2011-12-01

    Full Text Available Abstract Background The nonstructural protein 1 (NSP1 of rotavirus has been reported to block interferon (IFN signaling by mediating proteasome-dependent degradation of IFN-regulatory factors (IRFs and (or the β-transducin repeat containing protein (β-TrCP. However, in addition to these targets, NSP1 may subvert innate immune responses via other mechanisms. Results The NSP1 of rotavirus OSU strain as well as the IRF3 binding domain truncated NSP1 of rotavirus SA11 strain are unable to degrade IRFs, but can still inhibit host IFN response, indicating that NSP1 may target alternative host factor(s other than IRFs. Overexpression of NSP1 can block IFN-β promoter activation induced by the retinoic acid inducible gene I (RIG-I, but does not inhibit IFN-β activation induced by the mitochondrial antiviral-signaling protein (MAVS, indicating that NSP1 may target RIG-I. Immunoprecipitation experiments show that NSP1 interacts with RIG-I independent of IRF3 binding domain. In addition, NSP1 induces down-regulation of RIG-I in a proteasome-independent way. Conclusions Our findings demonstrate that inhibition of RIG-I mediated type I IFN responses by NSP1 may contribute to the immune evasion of rotavirus.

  16. Effects of all-trans retinoic acid on tumor recurrence and metastasis Efecto del ácido trans-retinoico sobre la recidiva tumoral y el desarrollo metastásico

    Directory of Open Access Journals (Sweden)

    I. García-Alonso

    2005-04-01

    Full Text Available Objective: all-trans-retinoic acid (ATRA promotes cell differentiation. We have studied its effect on the local recurrence and metastatic spreading of an experimental rhabdomyosarcoma in rats. Design: syngenic rhabdomyosarcoma cells (S4MH were inoculated s.c. in male WAG/RijCrl rats. After 25 days tumors were excised and a 40% hepatectomy was performed for all animals. Ten days later the rats were sacrificed and a thorough necropsy was performed. The animals were randomly allocated to receive daily doses of ATRA (5 mg/kg, i.p. or its solvent (Clinoleic®/ethanol 90/10, starting three days before surgery until the end of the experiment. Results: ATRA reduced the incidence of local recurrence from 70 to 33% (p Objetivo: el ácido trans-retinoico (ATRA, "all-trans retinoic acid" es un agente inductor de la diferenciación celular. Se estudia su efecto sobre la recidiva local y la diseminación metastásica de los tumores sólidos. Diseño experimental: mediante inoculación subcutánea de células de rabdomiosarcoma (S4MH se ha inducido un tumor en ratas WAG/RijCrl. Tras 25 días, se practicó una tumorectomía y simultáneamente hepatectomía del 40%. Los animales se sacrificaron el día 35, y fueron sometidos a estudio necrópsico. La mitad de los animales fueron tratados con ATRA (5 mg/kg, i.p. desde el día 22 al 35, mientras que los controles recibieron el excipiente (Clinoleico®/etanol 90/10. Resultados: el tratamiento redujo la tasa de recidiva local del 70 al 33% (p < 0,05, aunque no afectó a su tamaño (1,8 vs. 2,0 cc. El volumen medio de las metástasis inguinales se redujo a la sexta parte (0,2 vs. 1,2 cc; p < 0,05, si bien su frecuencia aumentó con el ATRA (86 vs. 29%; p < 0,05. La extensión retroperitoneal del rabdomisoarcoma también se redujo (0,7 vs. 5,1 cc; p < 0,05, aunque no hubo variación en la incidencia (71 vs. 67%. La incidencia de afectación pulmonar (100% en controles se redujo hasta el 33% (p < 0,05, a la vez que el

  17. Differentiation-inducing and anti-proliferative activities of isoliquiritigenin and all-trans-retinoic acid on B16F0 melanoma cells: Mechanisms profiling by RNA-seq.

    Science.gov (United States)

    Chen, Xiaoyu; Yang, Ming; Hao, Wenjin; Han, Jichun; Ma, Jun; Wang, Caixia; Sun, Shiguo; Zheng, Qiusheng

    2016-10-30

    Melanoma is a cancer that arises from melanocytes, specialized pigmented cells that are found predominantly in the skin. The incidence of malignant melanoma has significantly increased over the last decade. With the development of therapy, the survival rate of some kind of cancer has been improved greatly. But the treatment of melanoma remains unsatisfactory. Much of melanoma's resistance to traditional chemotherapy is believed to arise intrinsically, by virtue of potent growth and cell survival-promoting genetic alteration. Therefore, significant attention has recently been focused on differentiation therapy, as well as differentiation inducer compounds. In previous study, we found isoliquiritigenin (ISL), a natural product extracted from licorice, could induce B16F0 melanoma cell differentiation. Here we investigated the transcriptional response of melanoma differentiation process induced by ISL and all-trans-retinoic acid (RA). Results showed that 390 genes involves in 201 biochemical pathways were differentially expressed in ISL treatment and 304 genes in 193 pathways in RA treatment. Differential expressed genes (DGEs, fold-change (FC)≥10) with the function of anti-proliferative and differentiation inducing indicated a loss of grade malignancy characteristic. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis indicated glutathione metabolism, glycolysis/gluconeogenesis and pentose phosphate pathway were the top three relative pathway perturbed by ISL, and mitogen-activated protein kinase (MAPK) signaling pathway was the most important pathway in RA treatment. In the analysis of hierarchical clustering of DEGs, we discovered 72 DEGs involved in the process of drug action. We thought Cited1, Tgm2, Xaf1, Cd59a, Fbxo2, Adh7 may have critical role in the differentiation of melanoma. The evidence displayed herein confirms the critical role of reactive oxygen species (ROS) in melanoma pathobiology and provides evidence for future targets in the

  18. All-trans retinoic acid inhibits KIT activity and induces apoptosis in gastrointestinal stromal tumor GIST-T1 cell line by affecting on the expression of survivin and Bax protein

    Directory of Open Access Journals (Sweden)

    Taguchi Takahiro

    2010-12-01

    Full Text Available Abstract Background Imatinib, a selective tyrosine kinase inhibitor, has been used as a standard first-line therapy for irresectable and metastasized gastrointestinal stromal tumor (GIST patients. Unfortunately, most patients responding to imatinib will eventually exhibit imatinib-resistance, the cause of which is not fully understood. The serious clinical problem of imatinib-resistance demands alternative therapeutic strategy. This study was conducted to investigate the effect of all-trans retinoic acid (ATRA on GIST cell lines. Methods Cell proliferation was determined by trypan blue dye exclusion test. Western blot analysis was performed to test the expression of activated KIT, its downstream proteins, and apoptosis associated proteins. The cytotoxic interactions of imatinib with ATRA were evaluated using the isobologram of Steel and Peckham. Results and conclusion In this work, for the first time we have demonstrated that ATRA affected on cell proliferation of GIST-T1 and GIST-882 cell line through inhibition of cell growth in a dose dependent manner and induced apoptosis. High dose of ATRA induced morphologic change in GIST-T1 cells, rounded-up cells, and activated the caspase-3 protein. In further examination, we found that the ATRA-induced apoptosis in GIST-T1 cells was accompanied by the down-regulated expression of survivin and up-regulated expression of Bax protein. Moreover, ATRA suppressed the activity of KIT protein in GIST-T1 cells and its downstream signal, AKT activity, but not MAPK activity. We also have demonstrated that combination of ATRA with imatinib showed additive effect by isobologram, suggesting that the combination of ATRA and imatinib may be a novel potential therapeutic option for GIST treatment. Furthermore, the scracht assay result suggested that ATRA was a potential reagent to prevent the invasion or metastasis of GIST cells.

  19. Development of a validated UPLC method for simultaneous estimation of both free and entrapped (in solid lipid nanoparticles) all-trans retinoic acid and cholecalciferol (vitamin D3) and its pharmacokinetic applicability in rats.

    Science.gov (United States)

    Kumar, Manoj; Sharma, Gaurav; Singla, Dinesh; Singh, Sukhjeet; Sahwney, Sudhir; Chauhan, Anurag S; Singh, Gagandeep; Kaur, Indu Pal

    2014-03-01

    A sensitive ultra-performance liquid chromatography (UPLC) method was developed for simultaneous estimation of all-trans retinoic acid (ATRA) and cholecalciferol (vitamin D3) in rat plasma. The method was validated over the linear range of 1.0-5000ng/ml (r(2)=0.999) for both vitamins with a limit of detection of 0.5ng/ml. Chromatographic separation was achieved using liquid-liquid extraction (LLE) on an Acquity BEH RP 18 column (2.1mm×50mm, I.D. 1.7μm), with mobile phase comprising of acetonitrile:methanol:water (90:8:2, v/v/v), at a flow rate of 0.20ml/min and a total run time of 5min. Intra and inter-day variability (RSD) was ≤3.1%, and the accuracy varied between 95.4-99.9% and 95.3-101.1% respectively, for ATRA and 98.5-100.8% and 99.3-101.7%, respectively for vitamin D3. High recovery of ≥96.0% for ATRA and ≥87.80% for vitamin D3 was achieved. ATRA and vitamin D3 were stable in plasma under different storage and processing conditions. The method was applied to estimate the total drug content and entrapment efficiency of ATRA and vitamin D3 loaded solid lipid nanoparticles (SLNs). Concentration of these two agents was determined in rat plasma after simultaneous subcutaneous administration in free form or when loaded into SLNs thus establishing pharmacokinetic application of the developed procedure. Results indicated an improvement in AUC0-∞ by 5.4 times and 29.4 times for ATRA and vitamin D3, respectively, upon their incorporation into SLNs. Simultaneous administration of these two vitamins and their improved and prolonged bioavailability has scope for their use in treatment and control of tuberculosis.

  20. Validation of a liquid chromatography-electrospray ionization-tandem mass spectrometry method for determination of all-trans retinoic acid in human plasma and its application to a bioequivalence study.

    Science.gov (United States)

    Peng, Jing-Bo; Luo, Chen-Hui; Wang, Yi-Cheng; Huang, Wei-Hua; Chen, Yao; Zhou, Hong-Hao; Tan, Zhi-Rong

    2014-01-17

    A sensitive, reliable and specific LC-MS-MS method was developed and validated for the identification and quantitation of all-trans retinoic acid (ATRA) in human plasma. Acitretin was used as the internal standard (IS). After liquid-liquid extraction of 500 μL plasma with methyl tert-butyl ether (MTBE), ATRA and the IS were chromatographed on a HyPURITY C18 column (150 mm×2.1 mm, 5 μm) with the column temperature set at 40 °C. The mobile phase was consisted of 40% phase A (MTBE-methanol-acetic acid, 50:50:0.5, v/v) and 60% phase B (water-methanol-acetic acid, 50:50:0.5, v/v) with a flow rate of 0.3 mL/min. The API 4000 triple quadrupole mass spectrometer was operated in multiple reaction monitoring (MRM) mode via the positive electrospray ionization interface using the transition m/z 301.4→123.1 for ATRA and m/z 326.9→177.1 for IS, respectively. The calibration curve was linear over the range of 0.45-217.00 ng/mL (r≥0.999) with a lower limit of quantitation (LLOQ) of 0.45 ng/mL. The intra- and inter-day precisions values were below 8% relative standard deviation and the accuracy was from 98.98% to 106.19% in terms of relative error. The validated method was successfully applied in a bioequivalence study of ATRA in Chinese healthy volunteers.

  1. Validation of a Liquid Chromatography-Electrospray Ionization-Tandem Mass Spectrometry Method for Determination of All-Trans Retinoic Acid in Human Plasma and Its Application to a Bioequivalence Study

    Directory of Open Access Journals (Sweden)

    Jing-Bo Peng

    2014-01-01

    Full Text Available A sensitive, reliable and specific LC-MS-MS method was developed and validated for the identification and quantitation of all-trans retinoic acid (ATRA in human plasma. Acitretin was used as the internal standard (IS. After liquid-liquid extraction of 500 μL plasma with methyl tert-butyl ether (MTBE, ATRA and the IS were chromatographed on a HyPURITY C18 column (150 mm × 2.1 mm, 5 μm with the column temperature set at 40 °C. The mobile phase was consisted of 40% phase A (MTBE–methanol–acetic acid, 50:50:0.5, v/v and 60% phase B (water–methanol–acetic acid, 50:50:0.5, v/v with a flow rate of 0.3 mL/min. The API 4000 triple quadrupole mass spectrometer was operated in multiple reaction monitoring (MRM mode via the positive electrospray ionization interface using the transition m/z 301.4 → 123.1 for ATRA and m/z 326.9 → 177.1 for IS, respectively. The calibration curve was linear over the range of 0.45–217.00 ng/mL (r ≥ 0.999 with a lower limit of quantitation (LLOQ of 0.45 ng/mL. The intra- and inter-day precisions values were below 8% relative standard deviation and the accuracy was from 98.98% to 106.19% in terms of relative error. The validated method was successfully applied in a bioequivalence study of ATRA in Chinese healthy volunteers.

  2. Receptor-mediated delivery of all-trans-retinoic acid (ATRA) to hepatocytes from ATRA-loaded poly(N-p-vinylbenzyl-4-o-{beta}-D-galactopyranosyl-D-gluconamide) nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Seog-Jin [School of Agricultural Biotechnology, Seoul National University, Seoul 151-742 (Korea, Republic of) ; Moon, Hyun-Seuk [School of Agricultural Biotechnology, Seoul National University, Seoul 151-742 (Korea, Republic of) ; Guo, Ding-Ding [School of Agricultural Biotechnology, Seoul National University, Seoul 151-742 (Korea, Republic of) ; Kim, Sang-Heon [Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of) ; Akaike, Toshihiro [Department of Biomolecular Engineering, Tokyo Institute of Technology, Yokohama 226-8501 (Japan); Cho, Chong-Su [School of Agricultural Biotechnology, Seoul National University, Seoul 151-742 (Korea, Republic of) ]. E-mail: chocs@plaza.snu.ac.kr

    2006-01-15

    All-trans-retinoic acid (ATRA) plays a role in regulating CYP26 gene expression in hepatocytes. Poly(N-p-vinylbenzyl-4-o-{beta}-D-galactopyranosyl-D-gluconamide) (PVLA) nanoparticles have been used as hepatocyte-specific targeting candidates. The objective of this study was to investigate receptor-mediated delivery of ATRA using PVLA nanoparticles. ATRA-loaded PVLA nanoparticles were confirmed by {sup 1}H-nuclear magnetic resonance ({sup 1}H-NMR) and powder X-ray diffraction (XRD). In the {sup 1}H-NMR study, the proton signals of ATRA disappeared in the spectrum of ATRA-loaded PVLA nanoparticles in D{sub 2}O, whereas in dimethylsulfoxide-d{sub 6}, the spectrum seemed like an addition of the respective spectrum of each of the pure components. The crystalline peaks of ATRA disappeared in the XRD pattern of ATRA-loaded PVLA nanoparticles after ATRA was loaded into PVLA nanoparticles. In the measurement of size distribution, diameter of PVLA and ATRA-loaded PVLA nanoparticles in aqueous solution was 6.9 and 61.2 nm in number average, respectively. Flow cytometric analysis showed that the internalization of FITC-PVLA nanoparticles by hepatocytes in the absence of a competitive inhibitor was larger than preincubated with galactose. In reverse transcription-polymerase chain reaction (RT-PCR) analysis, ATRA-loaded PVLA nanoparticles induced CYP26A1 gene in hepatocytes in the absence of a competitive inhibitor but not preincubated with galactose. The results indicate that the ATRA-loaded PVLA nanoparticle can induce CYP26A1 gene in aqueous phase by an asialoglycoprotein receptor (ASGPR)-mediated delivery system.

  3. Granulocyte colony-stimulating factor potentiates differentiation induction by all-trans retinoic acid and arsenic trioxide and enhances arsenic uptake in the acute promyelocytic leukemia cell line HT93A.

    Science.gov (United States)

    Iriyama, Noriyoshi; Yuan, Bo; Hatta, Yoshihiro; Horikoshi, Akira; Yoshino, Yuta; Toyoda, Hiroo; Aizawa, Shin; Takeuchi, Jin

    2012-11-01

    The effects of arsenic trioxide (ATO), all-trans retinoic acid (ATRA) and granulocyte colony-stimulating factor (G-CSF), alone or in combination, were investigated by focusing on differentiation, growth inhibition and arsenic uptake in the acute promyelocytic leukemia (APL) cell line HT93A. ATO induced differentiation at low concentrations (0.125 µM) and apoptosis at high concentrations (1-2 µM). Furthermore, ATRA induced greater differentiation than ATO. No synergistic effect of ATRA and ATO was found on differentiation. G-CSF promoted differentiation-inducing activities of both ATO and ATRA. The combination of ATRA and G-CSF showed maximum differentiation and ATO addition was not beneficial. Addition of 1 µM ATRA and/or 50 ng/ml G-CSF to ATO did not affect apoptosis compared to ATO treatment alone. ATRA induced expression of aquaporin-9 (AQP9), a transmembrane transporter recognized as a major pathway of arsenic uptake, in a time- and dose-dependent manner. However, treatment with 1 µM ATRA decreased arsenic uptake by 43.7% compared to control subject. Although G-CSF addition did not enhance AQP9 expression in the cells, the reduced arsenic uptake was recovered to the same level as that in controls. ATRA decreased cell viability and addition of 50 ng/ml G-CSF to ATRA significantly increased the number of viable cells compared with that in ATRA alone treated cells. G-CSF not only promotes differentiation-inducing activities of both ATRA and ATO, but also makes APL cells vulnerable to increased arsenic uptake. These observations provide new insights into combination therapy using these three agents for the treatment of APL.

  4. All-Trans Retinoic Acid Modulates TLR4/NF-κB Signaling Pathway Targeting TNF-α and Nitric Oxide Synthase 2 Expression in Colonic Mucosa during Ulcerative Colitis and Colitis Associated Cancer

    Science.gov (United States)

    Rafa, Hayet; Benkhelifa, Sarra; AitYounes, Sonia; Saoula, Houria; Belhadef, Said; Belkhelfa, Mourad; Boukercha, Aziza; Toumi, Ryma; Soufli, Imene; de Launoit, Yvan; Mahfouf, Hassen; Nakmouche, M'hamed

    2017-01-01

    Colitis associated cancer (CAC) is the colorectal cancer (CRC) subtype that is associated with bowel disease such as ulcerative colitis (UC). The data on role of NF-κB signaling in development and progression of CAC were derived from preclinical studies, whereas data from human are rare. The aim of this work was to study the contribution of NF-κB pathway during UC and CAC, as well as the immunomodulatory effect of all-trans retinoic acid (AtRA). We analyzed the expression of NOS2, TNF-α, TLR4, and NF-κB, in colonic mucosa. We also studied NO/TNF-α modulation by LPS in colonic mucosa pretreated with AtRA. A marked increase in TLR4, NF-κB, TNF-α, and NOS2 expression was reported in colonic mucosa. The relationship between LPS/TLR4 and TNF-α/NO production, as well as the role of NF-κB signaling, was confirmed by ex vivo experiments and the role of LPS/TLR4 in NOS2/TNF-α induction through NF-κB pathway was suggested. AtRA downregulates NOS2 and TNF-α expression. Collectively, our study indicates that AtRA modulates in situ LPS/TLR4/NF-κB signaling pathway targeting NOS2 and TNF-α expression. Therefore, we suggest that AtRA has a potential value in new strategies to improve the current therapy, as well as in the clinical prevention of CAC development and progression.

  5. Internal tandem duplication of the FLT3 gene confers poor overall survival in patients with acute promyelocytic leukemia treated with all-trans retinoic acid and anthracycline-based chemotherapy: an International Consortium on Acute Promyelocytic Leukemia study.

    Science.gov (United States)

    Lucena-Araujo, Antonio R; Kim, Haesook T; Jacomo, Rafael H; Melo, Raul A; Bittencourt, Rosane; Pasquini, Ricardo; Pagnano, Katia; Fagundes, Evandro M; Chauffaille, Maria de Lourdes; Chiattone, Carlos S; Lima, Ana Silvia; Ruiz-Argüelles, Guillermo; Undurraga, Maria Soledad; Martinez, Lem; Kwaan, Hau C; Gallagher, Robert; Niemeyer, Charlotte M; Schrier, Stanley L; Tallman, Martin S; Grimwade, David; Ganser, Arnold; Berliner, Nancy; Ribeiro, Raul C; Lo-Coco, Francesco; Löwenberg, Bob; Sanz, Miguel A; Rego, Eduardo M

    2014-12-01

    Activating internal tandem duplication (ITD) mutations in the fms-like tyrosine kinase 3 (FLT3) gene (FLT3-ITD) are associated with poor outcome in acute myeloid leukemia, but their prognostic impact in acute promyelocytic leukemia (APL) remains controversial. Here, we screened for FLT3-ITD mutations in 171 APL patients, treated with all-trans retinoic acid (ATRA) and anthracycline-based chemotherapy. We identified FLT3-ITD mutations in 35 patients (20 %). FLT3-ITD mutations were associated with higher white blood cell counts (P < 0.0001), relapse-risk score (P = 0.0007), higher hemoglobin levels (P = 0.0004), higher frequency of the microgranular morphology (M3v) subtype (P = 0.03), and the short PML/RARA (BCR3) isoform (P < 0.0001). After a median follow-up of 38 months, FLT3-ITD(positive) patients had a lower 3-year overall survival rate (62 %) compared with FLT3-ITD(negative) patients (82 %) (P = 0.006). The prognostic impact of FLT3-ITD on survival was retained in multivariable analysis (hazard ratio: 2.39, 95 % confidence interval [CI] 1.17-4.89; P = 0.017). Nevertheless, complete remission (P = 0.07), disease-free survival (P = 0.24), and the cumulative incidence of relapse (P = 0.94) rates were not significantly different between groups. We can conclude that FLT3-ITD mutations are associated with several hematologic features in APL, in particular with high white blood cell counts. In addition, FLT3-ITD may independently predict a shorter survival in patients with APL treated with ATRA and anthracycline-based chemotherapy.

  6. All-Trans Retinoic Acid Modulates DNA Damage Response and the Expression of the VEGF-A and MKI67 Genes in ARPE-19 Cells Subjected to Oxidative Stress.

    Science.gov (United States)

    Tokarz, Paulina; Piastowska-Ciesielska, Agnieszka Wanda; Kaarniranta, Kai; Blasiak, Janusz

    2016-06-14

    Age-related macular degeneration (AMD) is characterized by the progressive degradation of photoreceptors and retinal pigment epithelium (RPE) cells. ARPE-19 is an RPE cell line established as an in vitro model for the study of AMD pathogenesis. Oxidative stress is an AMD pathogenesis factor that induces DNA damage. Thus, the oxidative stress-mediated DNA damage response (DDR) of ARPE-19 cells can be important in AMD pathogenesis. The metabolism of retinoids-which regulates cell proliferation, differentiation, and the visual cycle in the retina-was reported to be disturbed in AMD patients. In the present work, we studied the effect of all-trans retinoic acid (ATRA, a retinoid) on DDR in ARPE-19 cells subjected to oxidative stress. We observed that ATRA increased the level of reactive oxygen species (ROS), alkali-labile sites in DNA, DNA single-strand breaks, and cell death evoked by oxidative stress. ATRA did not modulate DNA repair or the distribution of cells in cell cycle in the response of ARPE-19 cells to oxidative stress. ATRA induced autophagy in the absence of oxidative stress, but had no effect on this process in the stress. ATRA induced over-expression of proliferation marker MKI67 and neovascularization marker VEGF-A. In conclusion, ATRA increased oxidative stress in ARPE-19 cells, resulting in more lesions to their DNA and cell death. Moreover, ATRA can modulate some properties of these cells, including neovascularization, which is associated with the exudative form of AMD. Therefore, ATRA can be important in the prevention, diagnosis, and therapy of AMD.

  7. Importance of interferon inducible trans-membrane proteins and retinoic acid inducible gene I for influenza virus replication: A review.

    Science.gov (United States)

    Suo, Siqingaowa; Ren, Xiaofeng

    2016-01-01

    Understanding the interplay between Influenza viruses and host cells is key to elucidating the pathogenesis of these viruses. Several host factors have been identified that exert antiviral functions; however, influenza viruses continue to replicate utilizing host cell machinery. Herein, we review the mechanisms of action of two host-derived proteins on conferring cellular resistance to the influenza virus; (1) the interferon inducible trans-membrane proteins, 1, 2 and 3, a recently identified family of early restriction factors; and (2) retinoic acid inducible gene I, a key mediator of antiviral immunity. These data may contribute to the design of novel and efficient anti-influenza treatments.

  8. Regulation of Retinoic Acid Inducible Gene-I (RIG-I Activation by the Histone Deacetylase 6

    Directory of Open Access Journals (Sweden)

    Helene Minyi Liu

    2016-07-01

    Full Text Available Retinoic acid inducible gene-I (RIG-I is a cytosolic pathogen recognition receptor that initiates the immune response against many RNA viruses. Upon RNA ligand binding, RIG-I undergoes a conformational change facilitating its homo-oligomerization and activation that results in its translocation from the cytosol to intracellular membranes to bind its signaling adaptor protein, mitochondrial antiviral-signaling protein (MAVS. Here we show that RIG-I activation is regulated by reversible acetylation. Acetyl-mimetic mutants of RIG-I do not form virus-induced homo-oligomers, revealing that acetyl-lysine residues of the RIG-I repressor domain prevent assembly to active homo-oligomers. During acute infection, deacetylation of RIG-I promotes its oligomerization upon ligand binding. We identify histone deacetylase 6 (HDAC6 as the deacetylase that promotes RIG-I activation and innate antiviral immunity to recognize and restrict RNA virus infection.

  9. All-trans retinoic acid effectively inhibits breast cancer stem cells growth in vitro%全反式维甲酸对乳腺癌干细胞的抑制作用

    Institute of Scientific and Technical Information of China (English)

    曾维根; 胡攀; 王佳妮; 刘仁斌

    2013-01-01

    目的 研究全反式维甲酸(ATRA)对乳腺癌干细胞的抑制作用.方法 采用CCK-8法检测ATRA对MCF-7和SK-BR-3细胞及其干细胞的抑制作用,并检测ATRA处理前后干细胞表型CD44+ CD24-的比例变化.利用球囊形成实验,研究ATRA对乳腺癌干细胞的自我更新能力的影响;将球囊贴壁培养,观察ATRA对干细胞分化的影响.结果 ATRA能够有效的抑制MCF-7和SK-BR-3细胞及其干细胞,但干细胞对ATRA更加敏感.10-6 mol/L ATRA对MCF-7细胞和干细胞的抑制率分别为(8.66±1.06)%和(21.09±3.25)% (P =0.004),对SK-BR-3细胞和干细胞的抑制率分别为(39.19 ±1.47)%和(51.22±2.80)% (P =0.005).ATRA能有效地抑制干细胞的成球能力,破坏其自我更新能力.10-6 mol/L ATRA处理后,MCF-7和SK-BR-3干细胞成球率分别为5.2% (5/96)和13.5% (13/96),而对照组分别为86.5%(83/96)和93.8%(90/96,均P<0.001).ATRA能促进CD44+ CD24-表型分化.10-6mol/L ATRA处理SK-BR-3干细胞后,CD44+ CD24-比例下降为(48.10±2.50)%,而对照组为(86.60±2.50)% (P <0.001).结论 ATRA能有效地抑制乳腺癌细胞和干细胞,但是对干细胞更敏感;ATRA能破坏乳腺癌干细胞的自我更新能力,并促进其分化.%Objective To detect the inhibitory effect of all-trans retinoic acid (ATRA) on breast cancer stem cells (CSCs).Methods The inhibitory effect of ATRA on MCF-7 and SK-BR-3 cell lines was analyzed using a Cell Counting Kit-8 (CCK-8).The proportion of CD44 + CD24-tumor cells of the two cell lines were measured before and after the ATRA treatment,and the role of ATRA in the regulation of CSC self-renewing ability was evaluated with a tumor sphere assay.The tumor spheres were grown in an adherent culture to evaluate the ATRA-induced differentiation of breast cancer stem cells.Results ATRA effectively inhibited the unsorted cells and stem cells,but the CSCs were more sensitive to ATRA.At a concentration of 10-6 mol/L,the inhibitory rate of MCF-7

  10. 全反式维甲酸治疗葡聚糖硫酸钠诱导的小鼠结肠炎%All-trans retinoic acid protects against dextran sulfate sodium-induced colitis in mice

    Institute of Scientific and Technical Information of China (English)

    洪凯; 张翼; 郭媛; 白爱平

    2013-01-01

    目的:探讨全反式维甲酸(all-trans retinoic acid,ATRA)对葡聚糖硫酸钠(dextran sulfate sodium,DSS)结肠炎治疗作用的机制.方法:将小鼠随机分成4组:正常对照组、DSS组、DS S+AT RA组和DSS+LE135组.建立小鼠DSS结肠炎的急性模型,从小鼠饮用DSS第3天开始,DSS+ATRA组、DSS+LE135组分别给予ATRA 0.5 mg/d、LE135 0.1 mg/d腹腔注射至实验结束.每天观察各组小鼠疾病活动指数(disease activity index,DAI),第8天颈椎脱臼处死小鼠取肠组织匀浆检测各组小鼠炎症肠段中髓过氧化物酶(myeloperoxidase,MPO)的含量,ELISA检测肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)的含量,免疫组织化学测定小鼠结肠CD68和核因子κB(nuclear factor κB,NF-κB) P65的表达,结果:(1)DAI评分:DSS+ATRA组小鼠的DAI评分为4.63±2.20,与DSS组、DSS+LE135组相比评分明显较低(P<0.05);对照组小鼠的DAI评分均为0;(2)组织学评分:DSS+ATRA组小鼠的组织学评分为7.63±1.19,与DSS组(10.13±1.36)、DSS+LE135组(10.38± 1.30)相比得分明显降低(P<0.05),但明显高于正常对照组(0.25±0.463);(3)MPO活性:DS S+ATRA组小鼠的MPO活性为7.88± 0.68,与空白对照(3.52±0.58)、DSS组(11.36 ±0.96)、DSS+LE135组(12.65±0.77)相比均有明显差异(P<0.05);(4)组织匀浆TNF含量:DSS+ATRA组(178.63±39.37),明显低于DSS组(316.67±43.68)、DSS+LE135组(362.45±62.75)这2组;(5)结肠组织CD68的表达:DSS+ATRA组肠黏膜固有层CD68阳性细胞数明显低于DSS组、DSS+LE135组(P<0.05),与对照组小鼠的CD68表达量相比明显增高(P<0.05);(6)结肠组织NF-κB的表达:DS S+ATRA组肠黏膜固有层NF-κB阳性细胞数明显低于DSS组、DSS+LE135组(P<0.05),与对照组NF-κB的表达量相比增高(P<0.05).结论:ATRA对DSS诱导的小鼠结肠炎具有治疗作用,机制为抑制结肠炎作用肠道免疫反应,及外周巨噬细胞向肠黏膜浸润.

  11. The influence of all-trans retinoic acid on the craniomaxillofacial development of mice%全反式维甲酸对小鼠颅颌面部发育影响的研究

    Institute of Scientific and Technical Information of China (English)

    陈沐; 杨旭; 刘学; 王伟财; 黄洪章

    2015-01-01

    目的:探讨妊娠期全反式维甲酸(atRA)摄入对胎鼠颅颌面部发育的影响。方法:C57BL 孕鼠随机分成4组(n =5),妊娠第10天,实验组分别给予60、80、100 mg/kg atRA)灌胃1次,对照组给予相同剂量的玉米油灌胃。第19天取胚胎,记录基本情况,取胎鼠头作头颅软组织侧貌分析,拍摄 X 线片作颅颌面部骨骼测量。结果:RA≥80 mg/kg 的2个实验组胎鼠体重减轻、体长缩短,出现明显颅颌面部畸形,畸胎率随 RA 剂量增高而升高。100 mg/kg 组胎鼠下颌体(BD)缩短,上颌骨(∠NAK)、下颌骨(∠NBD)后缩(P <0.01);∠SNG 则大于对照组(P <0.01)。X 线头影测量发现:维甲酸各剂量组胎鼠颅颌面部矢状向缩短(Op-Rh)(P <0.01);维甲酸≥80 mg/kg 的2个实验组胎鼠的颅穹窿长度(Pa-Na)和高度(Fp-Os)均小于对照组(P <0.05,P <0.01)。结论:维甲酸剂量依赖性抑制颅颌面部骨骼发育。%Objective:To study the influence of all-trans retinoic acid (atRA)on craniomaxillofacial development of C57 mice. Methods:Pregnant C57BL mice were divided into 4 groups(n =5)at gestation day (GD)1 0.Mice in three atRA-induction groups were given atRA of 60,80 and 1 00 mg/kg,respectively.The mice in control group were given the equivalent volume of corn oil.All pregnant mice were sacrificed at GD1 9 and the embryos were collected.Stereo microscope was used to observe the craniomaxillofacial morphology.Standardized radiographs were taken and cephalometric analysis was performed.Results:The embryonic body length and body mass of control group surpassed those of 80 and 1 00 mg/kg atRA groups(P <0.05,P <0.01 ).atRA induced craniomaxillofacial malformations and maldevelopment.The mice induced by atRA exhibited a shorter mandibular body and more retrusive position of max-illary and mandibular(∠NAK and ∠NBD)when compared with their norm(P <0

  12. EFFECTS OF ALL-TRANS RETINOIC ACID ON BLOOD COAGULATION AND FIBRINOLYSIS IN PATIENTS WITH ACUTE PROMYELOCYTIC LEUKEMIA%全反式维甲酸对APL病人凝血和纤溶指标影响

    Institute of Scientific and Technical Information of China (English)

    刘静; 汪洪毅

    2011-01-01

    Objective To observe changes of blood coagulation and fibrinolysis in patients with acute promyelocytic leukemia (APL) during remission following treatment by all-trans retinoic acid (ATRA) and investigate the relation of white blood cell (WBC) count in peripheral blood with ATRCA therapy for APL.Methods Initial therapy was offered to 45 APL patients, of whom, 21 with peripheral WBC count of ≥ 10 × 109/L (high-WBC group); 22 with WBC< 10 × 109/L (low-WBC group) 22 cases).Oral ATRA 60 mg/d.was given.To those with WBC>4.0 × 109/L, low-dose chemotherapy-daonomycin 20 mg/d for 3 days plus cytarabine 100 mg/day, for 7 days-was offered; to those with platelet of <20 × 109/L accompanied by hemorrhagic tendency, platelet suspension was transfused; to those infected, antibiotics were given.WBC, fibrinogen (FIB), prothrombin time (PT), activated partial thromboplastin time (APTT), and changes in bone marrow cells were monitored before treatment and one,two, and four weeks after ATRA therapy.Results Before ATRA therapy, FIB in high-WBC group was lower than that in lowWBC group (t= -3.082, P<0.05), while PT was higher than that in low-WBC group (t=3.720,P<0.05).There was no significant difference between the two groups in terms of APTT (t=- 1.157, P>0.05).Complete remission was achieved in 36 patients, partial remission in three, and non-remission in one.Three died of brain hemorrhage.After the first week of therapy, WBC count elevated, and gradually returned to normal until the fourth week (F=9.041 ,q=2.825-6.786,P<0.05).With the application of ATRA, plasma FIB and PT recovered by degrees, and reached to normal levels as complete remission achieved (F= 1 5.346,37.147;q=4.012- 13.673;P<0.05).Symptoms of bleeding were improved quickly.Conclusion The number of peripheral leukocytes in APL patients is an important risk factor of whether there is disseminated intravascular coagulation or not.After ATRA therapy, the early mortality due to bleeding declines

  13. Experimental study of the enhancement effect of aminopeptidase N inhibitor ubenimex on the differentiation induction activity of all-trans-retinoic acid in acute promyeiocytic leukemia cells and its mechanism

    Institute of Scientific and Technical Information of China (English)

    钱习军

    2006-01-01

    Objective To investigate the effect of aminopeptidase N inhibitor ubenimex on differentiation induction of alltrans -retinoic acid (ATRA) in acute promyelocytic leukemia (APL) cells and its mechanism. Methods The expression of CD11b was analyzed by flow cytometry and nitroblue-tetrazolium (NBT) reduction assay was per-

  14. MicroRNA and DNA methylation alterations mediating retinoic acid induced neuroblastoma cell differentiation.

    Science.gov (United States)

    Stallings, Raymond L; Foley, Niamh H; Bray, Isabella M; Das, Sudipto; Buckley, Patrick G

    2011-10-01

    Many neuroblastoma cell lines can be induced to differentiate into a mature neuronal cell type with retinoic acid and other compounds, providing an important model system for elucidating signalling pathways involved in this highly complex process. Recently, it has become apparent that miRNAs, which act as regulators of gene expression at a post-transcriptional level, are differentially expressed in differentiating cells and play important roles governing many aspects of this process. This includes the down-regulation of DNA methyltransferases that cause the de-methylation and transcriptional activation of numerous protein coding gene sequences. The purpose of this article is to review involvement of miRNAs and DNA methylation alterations in the process of neuroblastoma cell differentiation. A thorough understanding of miRNA and genetic pathways regulating neuroblastoma cell differentiation potentially could lead to targeted therapies for this disease.

  15. PI3K/AKT and ERK regulate retinoic acid-induced neuroblastoma cellular differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Qiao, Jingbo [Department of Pediatric Surgery, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); Paul, Pritha; Lee, Sora [Department of Pediatric Surgery, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); Department of Cancer Biology, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); Qiao, Lan; Josifi, Erlena; Tiao, Joshua R. [Department of Pediatric Surgery, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); Chung, Dai H., E-mail: dai.chung@vanderbilt.edu [Department of Pediatric Surgery, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); Department of Cancer Biology, Vanderbilt University Medical Center, Nashville, TN 37232 (United States)

    2012-08-03

    Highlights: Black-Right-Pointing-Pointer Retinoic acid (RA) induces neuroblastoma cells differentiation, which is accompanied by G0/G1 cell cycle arrest. Black-Right-Pointing-Pointer RA resulted in neuroblastoma cell survival and inhibition of DNA fragmentation; this is regulated by PI3K pathway. Black-Right-Pointing-Pointer RA activates PI3K and ERK1/2 pathway; PI3K pathway mediates RA-induced neuroblastoma cell differentiation. Black-Right-Pointing-Pointer Upregulation of p21 is necessary for RA-induced neuroblastoma cell differentiation. -- Abstract: Neuroblastoma, the most common extra-cranial solid tumor in infants and children, is characterized by a high rate of spontaneous remissions in infancy. Retinoic acid (RA) has been known to induce neuroblastoma differentiation; however, the molecular mechanisms and signaling pathways that are responsible for RA-mediated neuroblastoma cell differentiation remain unclear. Here, we sought to determine the cell signaling processes involved in RA-induced cellular differentiation. Upon RA administration, human neuroblastoma cell lines, SK-N-SH and BE(2)-C, demonstrated neurite extensions, which is an indicator of neuronal cell differentiation. Moreover, cell cycle arrest occurred in G1/G0 phase. The protein levels of cyclin-dependent kinase inhibitors, p21 and p27{sup Kip}, which inhibit cell proliferation by blocking cell cycle progression at G1/S phase, increased after RA treatment. Interestingly, RA promoted cell survival during the differentiation process, hence suggesting a potential mechanism for neuroblastoma resistance to RA therapy. Importantly, we found that the PI3K/AKT pathway is required for RA-induced neuroblastoma cell differentiation. Our results elucidated the molecular mechanism of RA-induced neuroblastoma cellular differentiation, which may be important for developing novel therapeutic strategy against poorly differentiated neuroblastoma.

  16. Regional differentiation of retinoic acid-induced human pluripotent embryonic carcinoma stem cell neurons.

    Directory of Open Access Journals (Sweden)

    Dennis E Coyle

    Full Text Available The NTERA2 cl D1 (NT2 cell line, derived from human teratocarcinoma, exhibits similar properties as embryonic stem (ES cells or very early neuroepithelial progenitors. NT2 cells can be induced to become postmitotic central nervous system neurons (NT2N with retinoic acid. Although neurons derived from pluripotent cells, such as NT2N, have been characterized for their neurotransmitter phenotypes, their potential suitability as a donor source for neural transplantation also depends on their ability to respond to localized environmental cues from a specific region of the CNS. Therefore, our study aimed to characterize the regional transcription factors that define the rostocaudal and dorsoventral identity of NT2N derived from a monolayer differentiation paradigm using quantitative PCR (qPCR. Purified NT2N mainly expressed both GABAergic and glutamatergic phenotypes and were electrically active but did not form functional synapses. The presence of immature astrocytes and possible radial glial cells was noted. The NT2N expressed a regional transcription factor code consistent with forebrain, hindbrain and spinal cord neural progenitors but showed minimal expression of midbrain phenotypes. In the dorsoventral plane NT2N expressed both dorsal and ventral neural progenitors. Of major interest was that even under the influence of retinoic acid, a known caudalization factor, the NT2N population maintained a rostral phenotype subpopulation which expressed cortical regional transcription factors. It is proposed that understanding the regional differentiation bias of neurons derived from pluripotent stem cells will facilitate their successful integration into existing neuronal networks within the CNS.

  17. A PU.1 suppressive target gene, metallothionein 1G, inhibits retinoic acid-induced NB4 cell differentiation.

    Directory of Open Access Journals (Sweden)

    Naomi Hirako

    Full Text Available We recently revealed that myeloid master regulator SPI1/PU.1 directly represses metallothionein (MT 1G through its epigenetic activity of PU.1, but the functions of MT1G in myeloid differentiation remain unknown. To clarify this, we established MT1G-overexpressing acute promyelocytic leukemia NB4 (NB4MTOE cells, and investigated whether MT1G functionally contributes to all-trans retinoic acid (ATRA-induced NB4 cell differentiation. Real-time PCR analyses demonstrated that the inductions of CD11b and CD11c and reductions in myeloperoxidase and c-myc by ATRA were significantly attenuated in NB4MTOE cells. Morphological examination revealed that the percentages of differentiated cells induced by ATRA were reduced in NB4MTOE cells. Since G1 arrest is a hallmark of ATRA-induced NB4 cell differentiation, we observed a decrease in G1 accumulation, as well as decreases in p21WAF1/CIP1 and cyclin D1 inductions, by ATRA in NB4MTOE cells. Nitroblue tetrazolium (NBT reduction assays revealed that the proportions of NBT-positive cells were decreased in NB4MTOE cells in the presence of ATRA. Microarray analyses showed that the changes in expression of several myeloid differentiation-related genes (GATA2, azurocidin 1, pyrroline-5-carboxylate reductase 1, matrix metallopeptidase -8, S100 calcium-binding protein A12, neutrophil cytosolic factor 2 and oncostatin M induced by ATRA were disturbed in NB4MTOE cells. Collectively, overexpression of MT1G inhibits the proper differentiation of myeloid cells.

  18. Control of antiviral defenses through hepatitis C virus disruption of retinoic acid-inducible gene-I signaling

    Science.gov (United States)

    Foy, Eileen; Li, Kui; Sumpter, Rhea; Loo, Yueh-Ming; Johnson, Cynthia L.; Wang, Chunfu; Fish, Penny Mar; Yoneyama, Mitsutoshi; Fujita, Takashi; Lemon, Stanley M.; Gale, Michael

    2005-01-01

    Hepatitis C virus (HCV) is a major human pathogen that infects 170 million people. A hallmark of HCV is its ability to establish persistent infections reflecting the evasion of host immunity and interference with α/β-IFN innate immune defenses. We demonstrate that disruption of retinoic acid-inducible gene I (RIG-I) signaling by the viral NS3/4A protease contributes to the ability of HCV to control innate antiviral defenses. RIG-I was essential for virus or HCV RNA-induced signaling to the IFN-β promoter in human hepatoma cells. This signaling was disrupted by the protease activity of NS3/4A, which ablates RIG-I signaling of downstream IFN regulatory factor 3 and NF-κB activation, attenuating expression of host antiviral defense genes and interrupting an IFN amplification loop that otherwise suppresses HCV replication. Treatment of cells with an active site inhibitor of the NS3/4A protease relieved this suppression and restored intracellular antiviral defenses. Thus, NS3/4A control of RIG-I supports HCV persistence by preventing IFN regulatory factor 3 and NF-κB activation. Our results demonstrate that these processes are amenable to restoration through pharmacologic inhibition of viral protease function. PMID:15710892

  19. Modeling and analysis of retinoic acid induced differentiation of uncommitted precursor cells.

    Science.gov (United States)

    Tasseff, Ryan; Nayak, Satyaprakash; Song, Sang Ok; Yen, Andrew; Varner, Jeffrey D

    2011-05-01

    Manipulation of differentiation programs has therapeutic potential in a spectrum of human cancers and neurodegenerative disorders. In this study, we integrated computational and experimental methods to unravel the response of a lineage uncommitted precursor cell-line, HL-60, to Retinoic Acid (RA). HL-60 is a human myeloblastic leukemia cell-line used extensively to study human differentiation programs. Initially, we focused on the role of the BLR1 receptor in RA-induced differentiation and G1/0-arrest in HL-60. BLR1, a putative G protein-coupled receptor expressed following RA exposure, is required for RA-induced cell-cycle arrest and differentiation and causes persistent MAPK signaling. A mathematical model of RA-induced cell-cycle arrest and differentiation was formulated and tested against BLR1 wild-type (wt) knock-out and knock-in HL-60 cell-lines with and without RA. The current model described the dynamics of 729 proteins and protein complexes interconnected by 1356 interactions. An ensemble strategy was used to compensate for uncertain model parameters. The ensemble of HL-60 models recapitulated the positive feedback between BLR1 and MAPK signaling. The ensemble of models also correctly predicted Rb and p47phox regulation and the correlation between p21-CDK4-cyclin D formation and G1/0-arrest following exposure to RA. Finally, we investigated the robustness of the HL-60 network architecture to structural perturbations and generated experimentally testable hypotheses for future study. Taken together, the model presented here was a first step toward a systematic framework for analysis of programmed differentiation. These studies also demonstrated that mechanistic network modeling can help prioritize experimental directions by generating falsifiable hypotheses despite uncertainty.

  20. Critical role of the H6-H7 loop in the conformational adaptation of all-trans retinoic acid and synthetic retinoids within the ligand-binding site of RARalpha.

    Science.gov (United States)

    Mailfait, S; Thoreau, E; Belaiche, D; Formstecher And B Sablonniè, P

    2000-06-01

    The pleiotropic effects of the natural and synthetic retinoids are mediated by the activation of the two subfamilies of nuclear receptors, the retinoic acid receptors (RARs) and the retinoic X receptors (RXRs). At the molecular level, these events begin with the specific ligand recognition by a nuclear receptor subtype. The adaptation of ligands to the receptor binding site leads to an optimal number of interactions for binding and selectivity which justifies elucidation of the structural requirements of the ligand binding pocket. To explore the contribution of H6-H7 loop folding in the ligand-induced conformational changes explained by the mouse-trap model, four RARalpha mutants were constructed. Ligand binding and transactivation studies revealed that three residues from the H6-H7 loop (Gly(301), Phe(302) and Gly(303)) are critical for the conformational adaptation of both synthetic agonists and antagonists. Model building and analysis of both RARalpha-ATRA and RARalpha-CD367 complexes demonstrate that accommodation of CD367 results in a less tight contact of the saturated ring of this ligand with the amino acid side chains of the receptor ligand-binding pocket compared with that of ATRA. According to the flexibility of the agonists tested (ATRA>TTNPB=Am580> CD367), we observed a decrease in binding that was dependent on ligand structure rigidity. In contrast, the binding and transactivating activities of the L266A mutant confirmed the structural constraints imposed by synthetic ligands on binding affinity for the receptor and revealed that subtle local rearrangements induced by specific conformational adaptation changes result in different binding affinities. Our results illustrate the dynamic nature of the interaction between RARalpha and its ligands and demonstrate the critical role of the H6-H7 loop in the binding of both synthetic retinoid agonists and antagonists.

  1. Functional and cellular characterization of human Retinoic Acid Induced 1 (RAI1 mutations associated with Smith-Magenis Syndrome

    Directory of Open Access Journals (Sweden)

    Carmona-Mora Paulina

    2010-08-01

    Full Text Available Abstract Background Smith-Magenis Syndrome is a contiguous gene syndrome in which the dosage sensitive gene has been identified: the Retinoic Acid Induced 1 (RAI1. Little is known about the function of human RAI1. Results We generated the full-length cDNA of the wild type protein and five mutated forms: RAI1-HA 2687delC, RAI1-HA 3103delC, RAI1 R960X, RAI1-HA Q1562R, and RAI1-HA S1808N. Four of them have been previously associated with SMS clinical phenotype. Molecular weight, subcellular localization and transcription factor activity of the wild type and mutant forms were studied by western blot, immunofluorescence and luciferase assays respectively. The wild type protein and the two missense mutations presented a higher molecular weight than expected, localized to the nucleus and activated transcription of a reporter gene. The frameshift mutations generated a truncated polypeptide with transcription factor activity but abnormal subcellular localization, and the same was true for the 1-960aa N-terminal half of RAI1. Two different C-terminal halves of the RAI1 protein (1038aa-end and 1229aa-end were able to localize into the nucleus but had no transactivation activity. Conclusion Our results indicate that transcription factor activity and subcellular localization signals reside in two separate domains of the protein and both are essential for the correct functionality of RAI1. The pathogenic outcome of some of the mutated forms can be explained by the dissociation of these two domains.

  2. Receptor for advanced glycation end products plays a more important role in cellular survival than in neurite outgrowth during retinoic acid-induced differentiation of neuroblastoma cells.

    Science.gov (United States)

    Sajithlal, Gangadharan; Huttunen, Henri; Rauvala, Heikki; Munch, Gerald

    2002-03-01

    The receptor for advanced glycation end products (RAGE), a member of the immunoglobulin superfamily, is known to interact with amphoterin. This interaction has been proposed to play a role in neurite outgrowth and process elongation during neurodifferentiation. However, there is as yet no direct evidence of the relevance of this pathway to neurodifferentiation under physiological conditions. In this study we have investigated a possible role of RAGE and amphoterin in the retinoic acid-induced differentiation of neuroblastoma cells. The functional inactivation of RAGE by dominant negative and antisense strategies showed that RAGE is not required for process outgrowth or differentiation, although overexpression of RAGE accelerates the elongation of neuritic processes. Using the antisense strategy, amphoterin was shown to be essential for process outgrowth and differentiation, suggesting that amphoterin may interact with other molecules to exert its effect in this context. Interestingly, the survival of the neuroblastoma cells treated with retinoic acid was partly dependent on the expression of RAGE, and inhibition of RAGE function partially blocked the increase in anti-apoptotic protein Bcl-2 following retinoic acid treatment. Based on these results we propose that a combination therapy using RAGE blockers and retinoic acid may prove as a useful approach for chemotherapy for the treatment of neuroblastoma.

  3. Protein phosphatase 2A associates with Rb2/p130 and mediates retinoic acid-induced growth suppression of ovarian carcinoma cells

    DEFF Research Database (Denmark)

    Vuocolo, Scott; Purev, Enkhtsetseg; Zhang, Dongmei

    2003-01-01

    Levels of Rb2/p130 protein are increased 5-10-fold following all-trans-retinoic acid (ATRA) treatment of the retinoid-sensitive ovarian adenocarcinoma cell line CAOV3, but not the retinoid-resistant adenocarcinoma cell line SKOV3. We found that this increase in Rb2/p130 protein levels in ATRA......-treated CAOV3 cells was the result of an increased protein stability. Moreover, Rb2/p130 exhibited a decreased ubiquitination following ATRA treatment. Because phosphorylation frequently mediates ubiquitination of proteins, we examined the serine/threonine phosphatase activity in our CAOV3 cells following ATRA...... treatment. A significant increase in Ser/Thr phosphatase activity was found, which correlated with a rise in the level of protein phosphatase 2A (PP2A) catalytic subunit-alpha. In addition, co-immunoprecipitation and glutathione S-transferase pull-down studies demonstrated that PP2A and Rb2/p130 associate...

  4. Effects of all-trans-retinoic acid and resveratrol on the gene expression of lysine-specific histone demethylase 1 in human melanoma cells A375%白藜芦醇和全反式维A酸对人黑素瘤细胞株A375 LSD-1表达的影响

    Institute of Scientific and Technical Information of China (English)

    徐观辉; 李建军; 张建青; 彭友华; 郑锦芬

    2011-01-01

    Objective: To investigate the effects of all-trans- retinoic acid (ATRA) and resveratrol (Res) on the expression of lysine- specific histone demethylase 1 (LSD- 1 ) in human melanoma cells A375. Methods: The inhibitive effects of ATRA and RES on human melanoma cells A375 were measured using MTT colorimetric assay. The morphology of A375 cells was observed by inverted microscope. The expression of LSD- 1 mRNA was detected by RT - PCR. Results: Both ATRA and Res inhibited proliferation of A375 cells. The mRNA of LSD - 1 was significantly decreased in A375 cells treated with 100 μmol/L Res and 25.0 μmol/L ATRA when compared to the control cells (P<0.05). However, there was no significant difference in down-regulation of LSD- 1 between 100 μmol/L Res and 25.0μmol/L ATRA ( P > 0.05). Conclusion: ATRA and Res can inhibit the expression of LSD1, which may play a role against tumors.%目的: 确定白藜芦醇(resveratrol,Res)和全反式维A酸(all-trans-retinoic acid,ATRA)对人黑素瘤细胞株A375赖氨酸特异性组蛋白去甲基化酶 1(LSD-1)基因表达的影响.方法: MTT比色法检测Res和ATRA对A375细胞增殖的抑制;倒置显微镜观察A375细胞形态的变化;RT-PCR方法检测LSD-1的mRNA的表达.结果: Res和ATRA均能抑制A375细胞的增殖.100 μmol/L Res及25.0 μmol/L ATRA均能显著减少人恶性黑素瘤细胞株A375中LSD-1的mRNA的表达, 与对照组比较差异均有统计学意义(P<0.05),但对LSD-1的下调作用无显著差异(P>0.05).结论: 抑制黑色素瘤细胞LSD-1的表达,可能是Res和ATRA抗肿瘤的途径之一.

  5. Evidence for genetic regulation of mRNA expression of the dosage-sensitive gene retinoic acid induced-1 (RAI1) in human brain

    Science.gov (United States)

    Chen, Li; Tao, Yu; Song, Fan; Yuan, Xi; Wang, Jian; Saffen, David

    2016-01-01

    RAI1 (retinoic acid induced-1) is a dosage-sensitive gene that causes Smith-Magenis syndrome (SMS) when mutated or deleted and Potocki-Lupski Syndrome (PTLS) when duplicated, with psychiatric features commonly observed in both syndromes. How common genetic variants regulate this gene, however, is unknown. In this study, we found that RAI1 mRNA expression in Chinese prefrontal and temporal cortex correlate with genotypes of common single nucleotide polymorphisms (SNPs) located in the RAI1 5′-upstream region. Using genotype imputation, “R2-Δ2” analysis, and data from the RegulomeDB database, we identified SNPs rs4925102 and rs9907986 as possible regulatory variants, accounting for approximately 30–40% of the variance in RAI1 mRNA expression in both brain regions. Specifically, rs4925102 and rs9907986 are predicted to disrupt the binding of retinoic acid RXR-RAR receptors and the transcription factor DEAF1 (Deformed epidermal autoregulatory factor-1), respectively. Consistent with these predictions, we observed binding of RXRα and RARα to the predicted RAI1 target in chromatin immunoprecipitation assays. Retinoic acid is crucial for early development of the central neural system, and DEAF1 is associated with intellectual disability. The observation that a significant portion of RAI1 mRNA expression is genetically controlled raises the possibility that common RAI1 5′-region regulatory variants contribute more generally to psychiatric disorders. PMID:26743651

  6. Clinical effect of compound qingdai tablets,all-trans retinoic acid and chemotherapy for treatment of acute promyelocytic leukemia of complete remission%复方青黛、ATRA与化疗交替治疗缓解后急性早幼粒细胞白血病

    Institute of Scientific and Technical Information of China (English)

    时新颖; 潘登; 郑顶运; 黄明

    2005-01-01

    目的:观察复方青黛片、全反式维A酸(all-trans retinoic acid,ATRA)与化疗交替治疗缓解后急性早幼粒细胞白血病(acute promyelocytic leukemia,APL)临床疗效.方法:对初诊24例APL 患者,先用复方青黛片或ATRA治疗达完全缓解,再用化疗与ATRA、复方青黛片序贯交替治疗,持续缓解3年以上者监测PML/RARα基因,再决定是否停药或继续治疗.结果:24例全部存活,复发率8.3%,未发现严重副作用.结论:复方青黛片、ATRA与化疗交替治疗APL疗效满意,副作用少.

  7. PROGRESS OF ALL-TRANS RETINOIC ACID PLUS ARSENIC TRIOXIDE IN TREATING ACTIVE PROMYELOCYTIC LEUKEMIA%全反式维甲酸和三氧化二砷治疗急性早幼粒细胞白血病APL的进展

    Institute of Scientific and Technical Information of China (English)

    陈赛娟; 赵萌; 陈竺

    2001-01-01

    @@ 一、引言急性早幼粒细胞白血病(Acute Promyelocytic Leukemia,APL)是FAB分型中急性非淋巴细胞白血病(Acute nonlymphocytic Leukemia ,ANLL)的M3亚型,占所有ANLL的10%~15%,具有独特的临床表现,细胞形态学,细胞遗传学和分子生物学特征.近十年的研究表明APL是第一个联合应用全反式维甲酸(all-trans retinoic acid,ATRA),三氧化二砷(Aa2O3)和化疗取得成功的人类恶性肿瘤,开创了诱导分化治疗的新篇章[1-3].本文总结了近年对APL分子发病机理,ARA和A2O3诱导分化/凋亡以及联合化疗的临床应用及其作用机制的研究概况.

  8. The cell cycle, cell death, and cell morphology during retinoic acid-induced differentiation of embryonal carcinoma cells

    NARCIS (Netherlands)

    Mummery, C.L.; Brink, C.E. van den; Saag, P.T. van der; Laat, S.W. de

    1984-01-01

    Abstract Time-lapse films were made of PC13 embryonal carcinoma cells, synchronized by mitotic shake off, in the absence and presence of retinoic acid. Using a method based on the transition probability model, cell cycle parameters were determined during the first five generations following synchron

  9. Genetic variation in toll-like receptors and retinoic acid-inducible gene I and outcome of hepatitis C virus infection: a candidate gene association study

    DEFF Research Database (Denmark)

    Clausen Nygaard, Louise; Ladelund, S; Weis, N;

    2014-01-01

    with resolution in the discovery cohort were genotyped in a validation cohort. Multivariate logistic regression adjusted for sex, hepatitis B surface antigen, HIV infection and the interleukin-28B rs12979860 SNP was performed in the combined cohort. Haplotype reconstruction and linkage disequilibrium analysis......We evaluated the effects of genetic variation in toll-like receptors (TLR), retinoic acid-inducible gene I (RIG-I) and their signalling pathways on spontaneous hepatitis C virus (HCV) resolution. We screened 95 single-nucleotide polymorphisms (SNPs) in 22 genes. SNPs significantly associated...... were performed. srs2233437, rs730775 and rs28362857 in Inhibitor of NF-kB ε (IkBε) and rs352140 in TLR9 were associated with spontaneous HCV resolution (P ≤ 0.05) in the discovery cohort (n = 308). In the validation cohort (n = 216), we replicated a significant association with HCV resolution for two...

  10. 全反式维甲酸在帕金森病大鼠模型中脑神经干细胞移植治疗中的作用%Transplantation of all-trans retinoic acid-treated midbrain-derived neural stem cell for Parkinson's disease in rats

    Institute of Scientific and Technical Information of China (English)

    盛汉松; 周辉; 许尚虞; 林坚; 尹波; 张弩

    2012-01-01

    目的 观察全反式维甲酸(atRA)处理的大鼠中脑神经干细胞(NSCs)移植对帕金森病(PD)模型大鼠的治疗作用.方法 制备PD大鼠模型并将成功模型分为对照组、常规培养中脑NSCs组和atRA处理中脑NSCs组(atRA+NSCs组).动态观察模型大鼠NSCs移植前后的行为学变化,定量分析纹状体多巴胺能神经元表达的变化.结果 atRA+NSCs组与对照组、NSCs组比较,实验动物的行为功能指标均得到有效改善(P<0.05或0.01).atRA+NSCs组与NSCs组大鼠纹状体移植区BrdU标记的酪氨酸羟化酶染色阳性细胞(TH+细胞)分别为(261.2±31.7)、(204.3±25.1)个,差异有统计学意义(P<0.05),而对照组纹状体区没有BrdU标记TH+细胞.结论 atRA在PD大鼠模型中脑NSCs移植治疗中有明显的促进作用,具有潜在的临床应用价值.%To evaluate the transplantation of all-trans retinoic acid (atRA)- treated midbrain-derived neuralstem cell (NSC) for Parkinson's disease (PD) in rats.MethodsThe PD model was induced by injection of 6-hydroxydopamine(6-OHDA) in right striatum in rats. The PD rats were divided into 3 groups: control group, NSC group (transplantation of midbrain-derived NSCs) and atRA+NSCs group (transplantation of atRA- treated NSCs). The rotation scores were assessed before and 1, 4, 8, 12 weeks after transplantation. The dopaminergic neurons in striatum were analyzed quantitatively using immunohis-tochemistry for tyrosine hydroxylaset TH).The apomorphine-induced rotation in atRA+NSCs group was decreased sig-nificantly compared with that of NSCs group (P<0.05) and control group (P<0.01). TH-positive neurons emerged in the striatum of atRA+NSCs and NSCs group was 261.2 ± 31.7 and 204.3 ±25.1 (P<0.05) after transplantation, but no TH-positive neurons were found in the control group.ConclusionAll-trans retinoic acid can enhance the efficacy of NSC transplantation for treatment of PD in rats.

  11. Disturbed apoptosis and cell proliferation in developing neuroepithelium of lumbo-sacral neural tubes in retinoic acid-induced spina bifida aperta in rat.

    Science.gov (United States)

    Wei, Xiaowei; Li, Hui; Miao, Jianing; Zhou, Fenghua; Liu, Bo; Wu, Di; Li, Shujing; Wang, Lili; Fan, Yang; Wang, Weilin; Yuan, Zhengwei

    2012-08-01

    Spina bifida is a complex congenital malformation resulting from failure of fusion in the spinal neural tube during embryogenesis. However, the cellular mechanism underlying spina bifida is not fully understood. Here, we investigated cell apoptosis in whole embryos and proliferation of neural progenitor cells in the spinal neural tube during neurulation in all-trans retinoic acid (atRA)-induced spina bifida in fetal rats. Cell apoptosis was assessed by TUNEL assay on whole-mount and serially sectioned samples of rat embryos with spina bifida. Cell proliferation of lumbo-sacral neural progenitor cells was assessed by staining for the mitotic marker Ki67 and pH3. We found an excess of apoptosis in the neuroepithelium of embryos with spina bifida, which became more marked as embryos progress from E11 to E13. Conversely, there was a reduction in cell proliferation in spina bifida embryos, with a progressively greater difference from controls with stage from E11 to 13. Thus, atRA-induced spina bifida in rat shows perturbed apoptosis and proliferation of neural progenitors in the lumbo-sacral spinal cord during embryonic development, which might contribute to the pathogenesis of spina bifida.

  12. Molecular remission in PML/RAR alpha-positive acute promyelocytic leukemia by combined all-trans retinoic acid and idarubicin (AIDA) therapy. Gruppo Italiano-Malattie Ematologiche Maligne dell'Adulto and Associazione Italiana di Ematologia ed Oncologia Pediatrica Cooperative Groups.

    Science.gov (United States)

    Mandelli, F; Diverio, D; Avvisati, G; Luciano, A; Barbui, T; Bernasconi, C; Broccia, G; Cerri, R; Falda, M; Fioritoni, G; Leoni, F; Liso, V; Petti, M C; Rodeghiero, F; Saglio, G; Vegna, M L; Visani, G; Jehn, U; Willemze, R; Muus, P; Pelicci, P G; Biondi, A; Lo Coco, F

    1997-08-01

    Two hundred fifty-three patients with newly diagnosed acute promyelocytic leukemia (APL) were eligible to enter the multicentric GIMEMA-AIEOP "AIDA" trial during the period July 1993 to February 1996. As a mandatory prerequisite for eligibility, all patients had genetic evidence of the specific t(15;17) lesion in their leukemic cells confirmed by karyotyping or by reverse transcription-polymerase chain reaction (RT-PCR) of the PML/RAR alpha fusion gene (the latter available in 247 cases). Median age was 37.8 years (range, 2.2 to 73.9). Induction treatment consisted of oral all-trans retinoic acid (ATRA), 45 mg/m2/d until complete remission (CR), given with intravenous Idarubicin, 12 mg/m2/d on days 2, 4, 6, and 8. Three polychemotherapy cycles were given as consolidation. Hematologic and molecular response by RT-PCR was assessed after induction and after consolidation. At the time of analysis, 240 of the 253 eligible patients were evaluable for induction. Of these, 11 (5%) died of early complications and 229 (95%) achieved hematologic remission. No cases of resistant leukemia were observed. Of 139 cases studied by RT-PCR after induction, 84 (60.5%) were PCR-negative and 55 (39.5%) PCR-positive. One hundred sixty-two patients were evaluable by RT-PCR at the end of consolidation. Of these, 159 (98%) tested PCR-negative and 3 (2%), PCR-positive. After a median follow up of 12 months (range, 0 to 33), the estimated actuarial event-free survival for the whole series of 253 eligible patients was 83% +/- 2.6% and 79% +/- 3.2% at 1 and 2 years, respectively. This study indicates that the AIDA protocol is a well-tolerated regimen that induces molecular remission in almost all patients with PML/RAR alpha-positive APL. Preliminary survival data suggest that a remarkable cure rate can be obtained with this treatment.

  13. Effects of melatonin and all-trans retinoic acids on the differentiation of spinal neural stem cells of embryo rat in vitro%褪黑素与全反式维甲酸共同作用对大鼠脊髓神经干细胞分化的影响

    Institute of Scientific and Technical Information of China (English)

    龚凯; 罗卓荆; 禹晓东; 褚尤标

    2006-01-01

    [目的]研究全反式维甲酸(all-trans retinoic acid,ATRA)与不同浓度的褪黑素(melatonin,MT)共同作用对体外培养的胚胎大鼠脊髓神经干细胞(neural stem cells,NSCs)向神经元方向分化的影响.[方法]取孕14 d的胚胎大鼠脊髓,原代培养出脊髓NSCs,传4代后分别加入ATRA与不同浓度的MT组合.采用细胞计数结合免疫荧光检测法,观察NSCs细胞的生长增殖及分化状况,并作统计学分析.[结果]与对照组[(8.8±1)%]相比,单纯ATRA作用组神经元分化比率[(10.6±2%]无明显差异;单纯MT作用组100 mol/L[(24.8±2)%]与10 nmol/LMT[23.4±1%)]2组都能明显促进脊髓NSCs向神经元分化,2组间比较无明显差异;ATPA与100 μmol/LMT共同作用组[(53.9±2)%],进一步提高了脊髓NSCs向神经元分化的比率;ATRA与10 nmol/LMT共同作用组[(26.7±2)%]也能促进脊髓NSCs向神经元方向分化(与对照组相比较),但其分化率与单一使用MT的2组比较无明显差异.[结论]单纯应用不同浓度的MT都促进脊髓源性的NSCs向神经元分化,但ATRA与不同浓度的MT联用对神经元分化率有着不同影响.

  14. A novel all-trans retinoic acid derivative 4-amino‑2‑trifluoromethyl-phenyl retinate inhibits the proliferation of human hepatocellular carcinoma HepG2 cells by inducing G0/G1 cell cycle arrest and apoptosis via upregulation of p53 and ASPP1 and downregulation of iASPP.

    Science.gov (United States)

    Liu, Hui; Chen, Feihu; Zhang, Ling; Zhou, Qing; Gui, Shuyu; Wang, Yuan

    2016-07-01

    4-Amino-2-trifluoromethyl-phenyl retinate (ATPR), a novel all-trans retinoic acid (ATRA) derivative, was reported to function as a tumor inhibitor in various types of cancer cells in vitro. However, little is known concerning its antitumor effect on human hepatocellular carcinoma (HCC) HepG2 cells. The aims of the present study were to investigate the effects of ATPR on the proliferation of HepG2 cells and to explore the probable mechanisms. A series of experiments were performed following the treatment of HepG2 cells with ATRA and ATPR. MTT and plate colony formation assays were used to measure the cell viability. To confirm the influence on proliferation, flow cytometry was used to detect the distribution of the cell cycle. Apoptosis was observed by Hoechst staining and flow cytometry. In addition, to characterize the underlying molecular mechanisms, immunofluorescence was applied to observe the distribution of p53. The transcription and translation levels of p53 were analyzed by real-time quantitative RT-PCR (qRT-PCR) and western blotting. The expression levels of murine double minute 2 (MDM2), apoptosis stimulating proteins of p53 (ASPP), cell cycle- and apoptosis-associated proteins were detected by western blotting. After HepG2 cells were incubated with ATRA and ATPR, the viability of the HepG2 cells was inhibited in a dose- and time-dependent manner. As well, ATPR significantly suppressed HepG2 cell colony formation and arrested cells at the G0/G1 phase, while ATRA had no obvious effects. Both Hoechst staining and flow cytometry unveiled the apoptosis of HepG2 cells. Moreover, the fluorescent density of p53 was higher in the nuclei after exposure to ATPR than that in the ATRA group. HepG2 cells treated with ATPR showed elevated mRNA and protein levels of p53 when compared with these levels in the ATRA-treated cells. Western blotting showed that ATPR increased ASPP1, p21 and Bax expression and decreased MDM2, iASPP, cyclin D and E, cyclin

  15. Modulation of fibroblast growth factor receptor expression and signalling during retinoic acid-induced differentiation of Tera-2 teratocarcinoma cells.

    Science.gov (United States)

    Pertovaara, L; Tienari, J; Vainikka, S; Partanen, J; Saksela, O; Lehtonen, E; Alitalo, K

    1993-02-26

    We have analyzed the regulation of fibroblast growth factor receptors (FGFRs) during retinoic acid (RA) induced differentiation of Tera-2 human embryonal carcinoma cells. Undifferentiated Tera-2 cells expressed mRNAs for all four known FGFRs. Their differentiation led to loss of FGFR-4 mRNA expression and mRNA levels for FGFR-2 and FGFR-3 were considerably downregulated, whereas the mRNA levels for FGFR-1 remained unaltered. A substantial decrease in binding of K-FGF was found to occur upon RA-induced differentiation of the cells. In undifferentiated Tera-2 cells FGF stimulation caused an increase of c-fos mRNA, and c-jun mRNAs, but no increase of junB mRNA, whereas in the differentiated cells, FGFs strongly stimulated the expression of all three genes. Thus differentiation of the Tera-2 cells leads to marked changes in FGFR gene expression as well as to complex alterations in their responses to exogenous FGFs.

  16. Role of Toll-like receptors and retinoic acid inducible gene I in endogenous production of type I interferon in dermatomyositis.

    Science.gov (United States)

    Li, Ling; Dai, Tingjun; Lv, Jingwei; Ji, Kunqian; Liu, Junling; Zhang, Bin; Yan, Chuanzhu

    2015-08-15

    To explore the possible mechanisms implicated in the endogenous production of type I interferons within the muscle tissue of dermatomyositis (DM) patients. We detected the co-localization of plasmacytoid dendritic cells (pDCs) with Toll-like receptors (TLRs) and retinoic acid inducible gene (RIG)-I by immunohistochemistry and immunofluorescence. Western blotting confirmed the expression of TLRs and RIG-I. TLR-3 and RIG-I was preferentially expressed in the perifascicular atrophy fibers of DM. TLR-7 was only in inflammatory infiltrates of a few DM patients. TLR-4 and TLR-9 was expressed mainly in inflammatory infiltrates. Immunofluorescence showed extensive co-localization of BDCA-2 with TLR-9 and little co-localization with TLR-7. Western blotting showed upregulation of expression of TLRs and RIG-I in DM compared with the controls. Our findings indicate that endogenous production of type I IFN in DM is generated by pDCs, mainly through the TLR-9 pathway and in part by TLR-7. TLR-3 and RIG-I are implicated in the formation of perifascicular atrophy in DM.

  17. Retinoic Acid Induces Embryonic Stem Cell Differentiation by Altering Both Encoding RNA and microRNA Expression.

    Directory of Open Access Journals (Sweden)

    Jingcheng Zhang

    Full Text Available Retinoic acid (RA is a vitamin A metabolite that is essential for early embryonic development and promotes stem cell neural lineage specification; however, little is known regarding the impact of RA on mRNA transcription and microRNA levels on embryonic stem cell differentiation. Here, we present mRNA microarray and microRNA high-output sequencing to clarify how RA regulates gene expression. Using mRNA microarray analysis, we showed that RA repressed pluripotency-associated genes while activating ectoderm markers in mouse embryonic stem cells (mESCs. Moreover, RA modulated the DNA methylation of mESCs by altering the expression of epigenetic-associated genes such as Dnmt3b and Dnmt3l. Furthermore, H3K4me2, a pluripotent histone modification, was repressed by RA stimulation. From microRNA sequence data, we identified two downregulated microRNAs, namely, miR-200b and miR-200c, which regulated the pluripotency of stem cells. We found that miR-200b or miR-200c deficiency suppressed the expression of pluripotent genes, including Oct4 and Nanog, and activated the expression of the ectodermal marker gene Nestin. These results demonstrate that retinoid induces mESCs to differentiate by regulating miR-200b/200c. Our findings provide the landscapes of mRNA and microRNA gene networks and indicate the crucial role of miR-200b/200c in the RA-induced differentiation of mESCs.

  18. Sonic hedgehog and retinoic Acid induce bone marrow-derived stem cells to differentiate into glutamatergic neural cells.

    Science.gov (United States)

    Yu, Zhenhai; Wu, Shixing; Liu, Zhen; Lin, Haiyan; Chen, Lei; Yuan, Xinli; Zhang, Zhiying; Liu, Fang; Zhang, Chuansen

    2015-01-01

    Studies have showed that transplanted stem cells in the inner ear won't regenerate to replace the damaged sensory hair cells. They can spontaneously differentiate into mesenchymal cells and fibrocytes in the damaged inner ear. Only mature sensory cells of MSCs-derived possess the great potency for cell transplantation in the treatment of sensorineural hearing loss. So, we try to establish an efficient generation of the glutamatergic sensory neural phenotype for the cell transplantation of the hearing loss. We isolated MSCs from femoral and tibial bones according to their adherence to culture dishes. After purification, proliferation, and passaged, cells became homogeneous in appearance, showing more uniformity and grew in a monolayer with a typical spindle-shape morphology. The cell surface markers were assessed using FACS to characterize the isolated cells. For neural induction to harvest the glutamatergic sensory neurons, passage 3 MSCs were incubated with preinduced medium for 24 hr, and neural-induced medium for an additional 14 days. The cells exhibit a typical neural shape. RT-PCR analysis indicated that the mRNA levels of the neural cell marker nestin, Tau, MAP-2, β-tubulin III, GluR-3, and GluR-4 were higher compared with primary MSCs. Immunohistochemistry and western-blotting proofed that nestin, MAP-2, β-tubulin III, and GluR-4 proteins indeed exhibit their expression difference in the induced cells compared to the MSCs. We show an efficient protocol by the combined applications of Sonic Hedgehog (Shh) and Retinoic Acid (RA) to induce MSCs to differentiate into the glutamatergic sensory neuron which were identified from the morphological, biochemical, and molecular characteristics.

  19. The Effects of All-Trans Retinoic Acid (ATRA) on the Expression of Ski in Cultured Rat Mesangial Cells Treated by TGF-β1%Ski在全反式维甲酸抑制TGF-β1诱导的系膜细胞增殖中的作用

    Institute of Scientific and Technical Information of China (English)

    苏宝凤; 王晓花; 张莉; 于莹; 陈晓岚

    2013-01-01

    目的 探讨全反式维甲酸(ATRA)对转化生长因子(TGF)-β1诱导的大鼠系膜细胞增殖及Ski表达的影响.方法 不同浓度ATRA预处理大鼠HBZY-I系膜细胞(为各剂量ATRA组)24 h后再加TGF-β1(10 μg/L)培养24 h.CCK-8法检测细胞增殖情况;Real-time PCR法检测Ski mRNA的表达;Western blot检测Ski蛋白的表达;激光共聚焦荧光显微镜检测Ski蛋白的亚细胞定位.并与正常对照组及TGF-β1组比较.结果 与正常对照组相比,TGF-β1组系膜细胞增殖明显,且Ski mRNA及蛋白表达升高(P<0.05);与TGF-β1组相比,ATRA能够呈剂量依赖性地抑制TGF-β1的促增殖作用,ATRA 10 μmol/L组Ski mRNA及蛋白表达量明显增高.ATRA组Ski蛋白主要定位于大鼠系膜细胞核,其细胞核荧光信号强度较TGF-β1组明显增强,细胞浆中荧光信号强度较TGF-β1组减弱.结论 ATRA可通过上调大鼠系膜细胞Ski表达,抑制其向核外转位,从而抑制TGF-β1诱导的系膜细胞增殖.%Objective To investigate the effects of all-trans retinoic acid (ATRA) on the expression of Ski in cultured rat mesangial cells treated by transforming growth factor (TGF-β1).Methods The mesangial cells were pre-treated with different concentrations of ATRA for 24 h, and then stimulated with TGF-β1 (10 μg/L) for 24 h.The cell proliferation was detected by CCK-8 method.The Ski mRNA expression was determined by real time-PCR.The protein expression of Ski was determined by Western blot analyses.The localization of Ski was observed by confocal fluorescence microscopy.Results Compared with the control group, TGF-β1 significantly enhanced the proliferation and the expression of Ski mRNA and protein in rat mesangial cells (P < 0.05).ATRA significantly inhibited mesangial cell proliferation induced by TGF-β1 in a dose-dependent manner.In ATRA groups, Ski mRNA and protein were increased significantly.Additionally, Ski protein was mainly localized in nucleus, and fluorescence intensity was

  20. Hepatitis C Virus Frameshift/Alternate Reading Frame Protein Suppresses Interferon Responses Mediated by Pattern Recognition Receptor Retinoic-Acid-Inducible Gene-I.

    Directory of Open Access Journals (Sweden)

    Seung Bum Park

    Full Text Available Hepatitis C virus (HCV actively evades host interferon (IFN responses but the mechanisms of how it does so are not completely understood. In this study, we present evidence for an HCV factor that contributes to the suppression of retinoic-acid-inducible gene-I (RIG-I-mediated IFN induction. Expression of frameshift/alternate reading frame protein (F/ARFP from HCV -2/+1 frame in Huh7 hepatoma cells suppressed type I IFN responses stimulated by HCV RNA pathogen-associated molecular pattern (PAMP and poly(IC. The suppression occurred independently of other HCV factors; and activation of interferon stimulated genes, TNFα, IFN-λ1, and IFN-λ2/3 was likewise suppressed by HCV F/ARFP. Point mutations in the full-length HCV sequence (JFH1 genotype 2a strain were made to introduce premature termination codons in the -2/+1 reading frame coding for F/ARFP while preserving the original reading frame, which enhanced IFNα and IFNβ induction by HCV. The potentiation of IFN response by the F/ARFP mutations was diminished in Huh7.5 cells, which already have a defective RIG-I, and by decreasing RIG-I expression in Huh7 cells. Furthermore, adding F/ARFP back via trans-complementation suppressed IFN induction in the F/ARFP mutant. The F/ARFP mutants, on the other hand, were not resistant to exogenous IFNα. Finally, HCV-infected human liver samples showed significant F/ARFP antibody reactivity, compared to HCV-uninfected control livers. Therefore, HCV F/ARFP likely cooperates with other viral factors to suppress type I and III IFN induction occurring through the RIG-I signaling pathway. This study identifies a novel mechanism of pattern recognition receptor modulation by HCV and suggests a biological function of the HCV alternate reading frame in the modulation of host innate immunity.

  1. Dose dependent activation of retinoic acid-inducible gene-I promotes both proliferation and apoptosis signals in human head and neck squamous cell carcinoma.

    Directory of Open Access Journals (Sweden)

    Jingzhou Hu

    Full Text Available The retinoic-acid-inducible gene (RIG-like receptor (RLR family proteins are major pathogen reorganization receptors (PRR responsible for detection of viral RNA, which initiates antiviral response. Here, we evaluated the functional role of one RLR family member, RIG-I, in human head and neck squamous cell carcinoma (HNSCC. RIG-I is abundantly expressed both in poorly-differentiated primary cancer and lymph node metastasis, but not in normal adjacent tissues. Activation of RIG-I by transfection with low dose of 5'-triphosphate RNA (3p-RNA induces low levels of interferon and proinflammatory cytokines and promotes NF-κB- and Akt-dependent cell proliferation, migration and invasion. In contrast, activation of RIG-I by a high dose of 3p-RNA induces robust mitochondria-derived apoptosis accompanied by decreased activation of Akt, which is independent of the interferon and TNFα receptor, but can be rescued by over-expression of constitutively active Akt. Furthermore, co-immunoprecipitation experiments indicate that the CARD domain of RIG-I is essential for inducing apoptosis by interacting with caspase-9. Together, our results reveal a dual role of RIG-I in HNSCC through regulating activation of Akt, in which RIG-I activation by low-dose viral dsRNA increases host cell survival, whereas higher level of RIG-I activation leads to apoptosis. These findings highlight the therapeutic potential of dsRNA mediated RIG-I activation in the treatment of HNSCC.

  2. Retinoic acid-induced gene-I (RIG-I) associates with nucleotide-binding oligomerization domain-2 (NOD2) to negatively regulate inflammatory signaling.

    Science.gov (United States)

    Morosky, Stefanie A; Zhu, Jianzhong; Mukherjee, Amitava; Sarkar, Saumendra N; Coyne, Carolyn B

    2011-08-12

    Cytoplasmic caspase recruiting domain (CARD)-containing molecules often function in the induction of potent antimicrobial responses in order to protect mammalian cells from invading pathogens. Retinoic acid-induced gene-I (RIG-I) and nucleotide binding oligomerization domain 2 (NOD2) serve as key factors in the detection of viral and bacterial pathogens, and in the subsequent initiation of innate immune signals to combat infection. RIG-I and NOD2 share striking similarities in their cellular localization, both localize to membrane ruffles in non-polarized epithelial cells and both exhibit a close association with the junctional complex of polarized epithelia. Here we show that RIG-I and NOD2 not only colocalize to cellular ruffles and cell-cell junctions, but that they also form a direct interaction that is mediated by the CARDs of RIG-I and multiple regions of NOD2. Moreover, we show that RIG-I negatively regulates ligand-induced nuclear factor-κB (NF-κB) signaling mediated by NOD2, and that NOD2 negatively regulates type I interferon induction by RIG-I. We also show that the three main Crohn disease-associated mutants of NOD2 (1007fs, R702W, G908R) form an interaction with RIG-I and negatively regulate its signaling to a greater extent than wild-type NOD2. Our results show that in addition to their role in innate immune recognition, RIG-I and NOD2 form a direct interaction at actin-enriched sites within cells and suggest that this interaction may impact RIG-I- and NOD2-dependent innate immune signaling.

  3. Molecular analysis of the Retinoic Acid Induced 1 gene (RAI1) in patients with suspected Smith-Magenis syndrome without the 17p11.2 deletion.

    Science.gov (United States)

    Vilboux, Thierry; Ciccone, Carla; Blancato, Jan K; Cox, Gerald F; Deshpande, Charu; Introne, Wendy J; Gahl, William A; Smith, Ann C M; Huizing, Marjan

    2011-01-01

    Smith-Magenis syndrome (SMS) is a complex neurobehavioral disorder characterized by multiple congenital anomalies. The syndrome is primarily ascribed to a ∼3.7 Mb de novo deletion on chromosome 17p11.2. Haploinsufficiency of multiple genes likely underlies the complex clinical phenotype. RAI1 (Retinoic Acid Induced 1) is recognized as a major gene involved in the SMS phenotype. Extensive genetic and clinical analyses of 36 patients with SMS-like features, but without the 17p11.2 microdeletion, yielded 10 patients with RAI1 variants, including 4 with de novo deleterious mutations, and 6 with novel missense variants, 5 of which were familial. Haplotype analysis showed two major RAI1 haplotypes in our primarily Caucasian cohort; the novel RAI1 variants did not occur in a preferred haplotype. RNA analysis revealed that RAI1 mRNA expression was significantly decreased in cells of patients with the common 17p11.2 deletion, as well as in those with de novo RAI1 variants. Expression levels varied in patients with familial RAI1 variants and in non-17p11.2 deleted patients without identified RAI1 defects. No correlation between SNP haplotype and RAI1 expression was found. Two clinical features, ocular abnormalities and polyembolokoilomania (object insertion), were significantly correlated with decreased RAI1 expression. While not significantly correlated, the presence of hearing loss, seizures, hoarse voice, childhood onset of obesity and specific behavioral aspects and the absence of immunologic abnormalities and cardiovascular or renal structural anomalies, appeared to be specific for the de novo RAI1 subgroup. Recognition of the combination of these features will assist in referral for RAI1 analysis of patients with SMS-like features without detectable microdeletion of 17p11.2. Moreover, RAI1 expression emerged as a genetic target for development of therapeutic interventions for SMS.

  4. Molecular analysis of the Retinoic Acid Induced 1 gene (RAI1 in patients with suspected Smith-Magenis syndrome without the 17p11.2 deletion.

    Directory of Open Access Journals (Sweden)

    Thierry Vilboux

    Full Text Available Smith-Magenis syndrome (SMS is a complex neurobehavioral disorder characterized by multiple congenital anomalies. The syndrome is primarily ascribed to a ∼3.7 Mb de novo deletion on chromosome 17p11.2. Haploinsufficiency of multiple genes likely underlies the complex clinical phenotype. RAI1 (Retinoic Acid Induced 1 is recognized as a major gene involved in the SMS phenotype. Extensive genetic and clinical analyses of 36 patients with SMS-like features, but without the 17p11.2 microdeletion, yielded 10 patients with RAI1 variants, including 4 with de novo deleterious mutations, and 6 with novel missense variants, 5 of which were familial. Haplotype analysis showed two major RAI1 haplotypes in our primarily Caucasian cohort; the novel RAI1 variants did not occur in a preferred haplotype. RNA analysis revealed that RAI1 mRNA expression was significantly decreased in cells of patients with the common 17p11.2 deletion, as well as in those with de novo RAI1 variants. Expression levels varied in patients with familial RAI1 variants and in non-17p11.2 deleted patients without identified RAI1 defects. No correlation between SNP haplotype and RAI1 expression was found. Two clinical features, ocular abnormalities and polyembolokoilomania (object insertion, were significantly correlated with decreased RAI1 expression. While not significantly correlated, the presence of hearing loss, seizures, hoarse voice, childhood onset of obesity and specific behavioral aspects and the absence of immunologic abnormalities and cardiovascular or renal structural anomalies, appeared to be specific for the de novo RAI1 subgroup. Recognition of the combination of these features will assist in referral for RAI1 analysis of patients with SMS-like features without detectable microdeletion of 17p11.2. Moreover, RAI1 expression emerged as a genetic target for development of therapeutic interventions for SMS.

  5. Effect of all trans-retinoic acid combined with suberoylanilide hydroxamic acid on breast cancer cells MCF-7%全反式维A酸联合辛二酰苯胺异羟肟酸对乳腺癌MCF-7细胞的作用

    Institute of Scientific and Technical Information of China (English)

    薛文潮; 李光; 张妮娜; 何涛

    2016-01-01

    Objective Induction and differentiation of tumor cells is a new therapy of cancer. Nowadays, differentiation inducing agents were widely used in treatment of acute lymphoblastic leukemia, therefore it is imperative to develop the investigation in vitro of solid tumors. This study was to combine all trans-retinoic acid (ATRA) and suberoylanilide hydroxamic acid (SAHA) on the proliferation of MCF-7 to investigate whether the combination of the two drugs have synergistic effect.Methods Human breast cancer cell line MCF-7 was culturedin vitro. When the cells entered the logarithmic growth phase, a certain concentration of ATRA (or) SAHA were added into the petri dishes. Morphological changes of cells were observed under inverted microscope, the anti-proliferative effect was measured by MTT assay. Absorbance value and inhibition rate were compared by repeated measurement data, using LSD for multiple comparison.Results Inverted microscope observation showed that, morphological changes of cells in ATRA combined with SAHA group was obvious than ATRA or SAHA group, and with the extension of time the effect was more remarkable. The absorbance value of A1 and B1 group was not statistically significant compared with the control group at 24 h (P=0.092). Compared with the control group, the B1 group had no statistical significance at 48 h (P=1.243). The average absorbance of each experimental group was less than that of the control group at 72 h, 96 h, 120 h (groups:F=320.648, P=0.000; different time-point:F=219.245,P=0.000; interaction:F=117.962,P=0.000). The proliferation inhibition rate of single drug group was higher than that of the control group, and the ATRA combined with SAHA group was significantly higher than that in the single drug group (groups:F=462.792, P=0.000; different time-point:F=315.024,P=0.000; interaction:F=179.682,P=0.000); q values in A1+B1 group and A2+B1 group of combined effects of two drugs at 24 h and 48 h were greater than 1.15, performed as

  6. Study on the inhibitory effects and related toxicity of all-trans-retinoic acid combined with arsenic trioxide on transplanted tumor of human bladder neoplasms in nude mice%全反式维甲酸联合三氧化二砷抗膀胱癌作用及其毒副作用的实验研究

    Institute of Scientific and Technical Information of China (English)

    周振玉; 张永; 陈家存

    2011-01-01

    目的 观察全反式维甲酸(ATRA)联合三氧化二砷(As2 O3)对膀胱癌细胞株BIU-87裸鼠移植瘤生长的抑制作用,及其毒副作用。方法建立人膀胱癌裸鼠皮下移植瘤模型40只,随机等分为4组:对照组,ATRA组,As2 O3组,ATRA和As2O3联合用药组;裸鼠瘤体内连续注射用药14d。停药后48 h检测血常规和肝、肾功能;处死裸鼠,测量移植瘤体积、重量,计算抑瘤率;移植瘤及心、肝、肾等组织HE染色,观察其病理变化;瘤组织免疫组化S-P法检测血管内皮生长因子(VEGF)表达、CD43标记的微血管密度MVD的表达。结果与对照组比较,As2 O3组及ATRA组移植瘤生长明显受到抑制(质量抑瘤率分别为43.77%,41.82%),两者联合用药后,抑制作用显著增强(质量抑瘤率为68.55%),抑瘤率差异具有统计学意义(x2 =26.81,P<0.01);As2O3组、ATRA组、联合用药组均不同程度下调VEGF表达(OD值分别为27.33±2.17,20.72±2.01,19.23±2.32,17.16±1.59)及MVD的表达(OD值分别为141.12±8.38,43.39±7.41,44.77±8.25,30.56±7.71),联合用药组下调最显著;各用药组均出现轻度白细胞抑制(t =3.16,3.08,3.37,P<0.01),联合用药组抑制程度与单一用药组比较差异无统计学意义(P>0.05),肝、肾功能各指标比较差异均无统计学 意义(P>0.05)。结论ATRA联合As2 O3在体内能够协同抑制膀胱癌BIU-87细胞移植瘤的生长和血管生成,仅有白细胞轻度抑制,对肝肾功能无毒副作用。%Objective To investigate the inhibitory effects and related toxicity of all-trans-retinoic acid(ATRA) combined with arsenic trioxide(As2O3) on transplanted human bladder neoplasms in nude mice.Methods The subcutaneously transplanted tumor models of human bladder neoplasms in nude mice were established and then it was randomly divided into four teams: Saline group, ATRA group, As2 O3 group and the combination of ATRA and As2 O3 group.Each group

  7. Differentiating effect of PPARγ ligand rosiglitazone and all trans-retinoic acid on myeloma cells and its possible mechanism%罗格列酮与全反式维甲酸对骨髓瘤细胞分化的影响及其可能机制

    Institute of Scientific and Technical Information of China (English)

    黄海雯; 陈广华; 常惠荣; Howard C.H.Chow; Anska Y.H.Leung; Raymond Liang; 吴德沛

    2009-01-01

    Objective To investigate the effects of PPARγ ligand(rosiglitazone,RGZ)as well as combined with all trans-retinoic acid(ATRA)on human myeloma cells and try to explore the possible mechanism.Methods Human myeloma cell lines U266 and RPMl.8226 cells were treated with RGZ in the presence or absence of ATRA.Cell proliferation was evaluated by [~3H] thymidine incorporation,cell cycle distribution and CD49e expression were analyzed by flow cytometry,morphology changes were evaluated by Wright-Giemsa staining.and p27~(Klpl)and p21~(Wafl)expression was detected by Western blotting.Results The exposure to RGZ induced proliferation inhibifion in both cell Iines in a dose-dependent manner.After cultured with 5 μmol/L RGZ,the proportion of U266 and RPMl-8226 cells in phase G_0/G_1 was(45.2±6.7)%and(40.3±7.3)%,respectively(P<0.05).The proportion of the cells in phase G_2/M and Swag(52.2±7.4)%and(57.4±9.5)%,respectively(P<0.05).These changes were more evident when the RGZ concentration was increased to 10 μmol/L.A combination of RGZ with ATRA enhanced the growth inhibition and eell cycle arrest effects of RGZ.The RGZ-treated myeloma cells displayed morphological characteristics of cell difierentiation.and more evident signs of differentiation were observed when RGZ wag combined with ATRA.These changes were confirmed by the detection of CD49e expression.The expression of p27~(Klpl)and p21~(Wafl)in myeloma cells was up-regulated by RGZ and this change Was more apparent when RGZ was used in combination with ATRA.Conclusion RGZ Can induce cell cycle arrest and cell differentiation in myeloma cells which maybe caused by up-regulation of p27~(Klpl)and p21~(Wafl)expression.ATRA can enhance these effects of RGZ on multiple myeloma cells and combined nile of thesetwo drugs may show a synergistic effect on myeloma cells.%目的 探讨过氧化物酶体增殖物活化受体γ(PPARγ)的配体罗格列酮(RGZ)与全反式维甲酸(ATRA)对骨髓瘤细胞分化的

  8. microRNAs expression profile in acute promyelocytic leukemia cell differentiation induced by all-trans retinoic acid and arsenic trioxide%全反式维甲酸和三氧化二砷诱导急性早幼粒细胞白血病细胞分化前后微小RNA表达变化

    Institute of Scientific and Technical Information of China (English)

    吴勇; 李先芳; 杨景辉; 廖晓莹; 陈元仲

    2012-01-01

    目的 研究急性早幼粒细胞白血病(APL)细胞分化前后微小RNA(miRNA,miR)表达变化.方法 采用全反式维甲酸(ATRA)和三氧化二砷(As2O3)诱导APL细胞系NB4 细胞分化,瑞氏-姬姆萨染色观察细胞形态,流式细胞术检测细胞表面标志CD11b的表达,用实时定量RT-PCR检测miRNA表达谱miR-15b、miR-16、miR-34a、miR-107、miR-124a、miR-146、miR-155、miR-181a、miR-223、miR-342、let7c等miRNA的表达水平,用2-△△Ct法计算miRNA相对表达水平.收集15例APL初诊和15例APL缓解期患者骨髓单个核细胞(MNC),用RT-PCR检测MNC miRNA 的表达水平,用2-△Ct法计算miRNA表达水平.结果 ATRA作用NB4细胞96 h,miR-15b、miR-16、miR-107、miR-223、miR-342表达水平均显著上调,分别为对照组的3.40、4.22、5.41、20.03和5.29倍,As2O3作用NB4细胞96 h,miR-15b、miR-16、miR-107、miR-223、miR-342表达水平也显著上调,分别为对照组的3.62、2.49、2.58、4.27和1.94倍,除miR-15b外,ATRA处理组miR-16、miR-107、miR-223和miR-342表达水平上调程度均高于As2O3处理组,其中尤以miR-223为甚.ATRA和As2O3治疗后缓解期APL患者miR-15b、miR-16、miR-107、miR-181a、miR-223和miR-342表达水平(2-△Ct值)分别为0.4137、0.6367、0.1260、0.0522、0.6611和0.0280,而APL初诊患者miR-15b、miR-16、miR-107、miR-181a、miR-223、miR-342表达水平分别为0.0751、0.2022、0.0425、0.3064、0.1733和0.0090,APL缓解期miR-15b、miR-16、miR-107、miR-223和miR-342表达水平高于APL初诊者(P值均<0.05),而APL缓解期miR-181a表达水平低于APL初诊者(P<0.05).结论 特定miRNA参与APL细胞分化过程.%Objective To study the expression profile of microRNAs in acute promyelocytic leukemia (APL) cells during differentiation. Methods Differentiation of APL cell line NB4 cells was induced by all-trans retinoic acid (ATRA) and arsenic trioxide (As2O3). Morphological and immunological assay was performed by Wright-Giemsa staining and flow

  9. 活化素A和视黄酸诱导骨髓间充质干细胞体外分化为胰岛素分泌细胞%In vitro differentiation of bone marrow mesenchymal stem cells induced by activin A and all-trans retinoic acid into insulin-producing cells

    Institute of Scientific and Technical Information of China (English)

    王启伟; 于瑾; 刘兴茂; 李世崇; 叶玲玲; 刘红; 吴本传; 陈昭烈

    2006-01-01

    human being in the 21st century. Islet transplantation is considered to be the most effective approach to cure type Ⅰ diabetes mellitus. However, lack of donor tissue limits the application of this therapy. However, recent progress of stem cell research shows that stem cell therapy may be a potential means to solve this problem.OBJECTIVE: To take activin A and all-trans retinoic acid (AR) in inducing the differentiation of bone marrow mesenchymal stem cells (MSCs) and explore its possibility DESIGN: A randomized controlled experiment.SETTING: Institute of Biotechnology, Academy of Military Medical SciencesMATERIALS: This experiment was conducted at the Institute of Biotechnology, Academy of Military Medical Sciences from November 2004to June 2005. Six male Sprague-Dawley rats, with body mass of 150-160g, were provided by the Experimental Animal Center of Academy of Military Medical Sciences.METHODS: Femoral bone marrow of the rats was extracted under aseptic condition. Bone marrow mesenchymal stem cells (MSCs) were isolated with density gradient centrifugation. Passaged MSCs were randomly divided into 4 groups: high concentration of glucose (HG), AR, beta-mercaptoethanol (ME) and negative control groups. MSCs were induced to differentiate into IPCs with conditional medium containing high concentration glucose, activin A, RA and ME etc. After induction, phenotypes of differentiated cells were examined by immunocytochemistry and reverse transcription-polymerase chain reaction (RT-PCR).MAIN OUTCOME MEASURES: Expression of insulin and glucagon of differentiated cells were examined by immunocytochemistry. Insulin-1 mR-NA expression of differentiated cells was detected by RT-PCR.RESULTS: After bone marrow mesenchymal stem cells were induced,there were scattered insulin-and glucagon-positive cells in the HG group,many insulin-and glucagon-positive cells in the AR and ME groups, and these cells formed insulin-like structure. The expression of insulin-1mRNA could be observed

  10. Supercritical fluid extraction of all-trans-lycopene from tomato.

    Science.gov (United States)

    Gómez-Prieto, M Salud; Caja, M Mar; Herraiz, Marta; Santa-María, Guillermo

    2003-01-01

    A procedure is proposed for the supercritical fluid extraction of all-trans-lycopene from tomato using carbon dioxide at 40 degrees C without modifier. The present method minimizes the risk of degradation via isomerization and oxidation of health-promoting ingredients, such as lycopene. The effect of different experimental variables on the solvating power of the supercritical fluid was evaluated in terms of both the selectivity achievable in the process and the yield of the extraction of all-trans-lycopene. Satisfactory separations of the all-trans-lycopene isomers from the cis counterparts were achieved using a C(30) column. The obtained extract contained 88% all-trans-lycopene and 12% cis-lycopene.

  11. Retinoic acid-induced IgG production in TLR-activated human primary B cells involves ULK1-mediated autophagy.

    Science.gov (United States)

    Eriksen, Agnete Bratsberg; Torgersen, Maria Lyngaas; Holm, Kristine Lillebø; Abrahamsen, Greger; Spurkland, Anne; Moskaug, Jan Øivind; Simonsen, Anne; Blomhoff, Heidi Kiil

    2015-01-01

    In the present study we have established a vital role of autophagy in retinoic acid (RA)-induced differentiation of toll-like receptor (TLR)-stimulated human B cells into Ig-secreting cells. Thus, RA enhanced autophagy in TLR9- and CD180-stimulated peripheral blood B cells, as revealed by increased levels of the autophagosomal marker LC3B-II, enhanced colocalization between LC3B and the lysosomal marker Lyso-ID, by a larger percentage of cells with more than 5 characteristic LC3B puncta, and by the concomitant reduction in the level of SQSTM1/p62. Furthermore, RA induced expression of the autophagy-inducing protein ULK1 at the transcriptional level, in a process that required the retinoic acid receptor RAR. By inhibiting autophagy with specific inhibitors or by knocking down ULK1 by siRNA, the RA-stimulated IgG production in TLR9- and CD180-mediated cells was markedly reduced. We propose that the identified prominent role of autophagy in RA-mediated IgG-production in normal human B cells provides a novel mechanism whereby vitamin A exerts its important functions in the immune system.

  12. Glycolipid core structure switching from globo- to lacto- and ganglio-series during retinoic acid-induced differentiation of TERA-2-derived human embryonal carcinoma cells.

    Science.gov (United States)

    Fenderson, B A; Andrews, P W; Nudelman, E; Clausen, H; Hakomori, S

    1987-07-01

    We have analyzed the glycolipid markers of a recently cloned human embryonal carcinoma (EC) cell line, NTERA-2, which differentiates extensively into a variety of somatic cell types when exposed to retinoic acid. These tumor cells provide a model system that can be used to study the ontogeny of glycolipid diversity during human embryonic development. Glycolipid antigens were identified by cell surface immunofluorescence and thin-layer chromatography immunostaining using a comprehensive set of anticarbohydrate monoclonal antibodies. Undifferentiated NTERA-2 cells were found to express predominantly globo-series glycolipids, including Gb3, Gb5 (IV3GalGb4), globo-ganglioside (IV3NeuAc alpha 2----3GalGb4), globo-H (IV3Fuc alpha 1----2GalGb4), and globo-A (IV3GalNAc alpha 1----3[Fuc alpha 1----2]GalGb4). When NTERA-2 cells were induced to differentiate by culturing in the presence of 10(-5) M retinoic acid, a remarkable shift of cellular glycolipids from globo-series to lacto- and ganglio-series was observed: Globo-series structures declined, particularly during the period 7-20 days after first exposure to retinoic acid, while lacto-series structures, including fucosyl alpha 1----3 type 2 chain (Lex) and sialosyl type 2 chain, and ganglio-series structures, including GM3, GD3, 9-O-acetyl-GD3, GM2, GD2, and GT3, increased. The presence of globo-A and globo-H as the major ABH blood group antigens in undifferentiated NTERA-2 cells suggests that globo-series blood group antigens are embryonic antigens, synthesis of which switches to lacto-series during human development. Two-color immunofluorescence analysis indicated preferential expression of several ganglio- and lacto-series antigens on different subsets of differentiated cells and permitted the relationship of these subsets to the development of neurons in NTERA-2 cultures to be determined. The results suggest that glycosyltransferase, particularly those involved in controlling glycoconjugate core structure assembly

  13. Effects of all-trans retinoic acid combined with gamma radiation on proliferation and apoptosis of esophageal carcinoma TE13 cells%全反式维甲酸联合射线对食管癌细胞TE13增殖及凋亡的影响

    Institute of Scientific and Technical Information of China (English)

    邓秋媛; 董稚明

    2012-01-01

    Objective: To investigate the effects of ATRA (all-trans-retinoicacid) combined with gamma radiation on proliferation and apoptosis of human esophageal carcinoma TE1 3 cells, and to explore the possible mechanism. Methods: The effect of ATRA on the proliferation of TE13 cells was detected by MTT method. When the cell growth Rl (inhibitory rate) reached levels of 25%, 50% and 75%, the TE13 cells were treated with the corresponding inhibitory doses of ATRA combined with 4 Gy gamma radiation. The effects of this combination intervention on cell cycle distribution and apoptosis of TE13 cells were detected by FCM (flow cytometry). The colony-formation ability and cell viability were detected using colony-formation experiment. The expression of cyclinDl protein was detected by FCM. Results: The inhibitory effect of ATRA on the proliferation of TE1 3 cells was significant in a dose- and time-dependent manner. The cell growth Irs reached 22.0%, 55.1% and 71.1% at ATRA concentrations of 0.78, 6.25 and 12.5 μmol/L, respectively. The cell viability and colony-formation efficiency were significantly decreased in TE13 cells treated with ATRA in combination with 4 Gy gamma radiation, as compared with TE13 cells receiving administration of ATRA alone. The proliferative ability of TE1 3 cells was significantly reduced after ATRA treatment in combination with 4 Gy gamma radiation for 24 and 48 h; furthermore, the percentage of the cells arrested at phase Go/G, was increased accompanying with a significantly elevated apoptotic rate. Although the combination treatment (0.78 (imol/L ATRA and gamma radiation) had a weak influence on the expression of cyclinDl protein, which was significantly decreased in other groups (6.25 and 12.5 μmol/L ATRA). Conclusion: ATRA exerts an inhibitory influence on the proliferation of TE1 3 cells through down-regulating cyclinDl expression, arresting the cells at phase G0/G1 and inducing apoptosis. A higher-concentration of ATRA combined with gamma

  14. EFFECT OF 1,25-(OH)2D3 COMBINED WITH ALL-TRANS RETINOIC ACID ON FOXP3 EXPRESSION IN TREG CELLS IN MICE WITH ULCERATIVE COLITIS%1,25-(OH)2D3和全反式视黄酸联合应用对溃疡性结肠炎小鼠TREG细胞Foxp3表达的影响

    Institute of Scientific and Technical Information of China (English)

    张小艳; 杨雯; 张英; 李秀花; 邱服斌

    2016-01-01

    目的 探讨1,25-(OH)2D3和全反式视黄酸(all-trans retinoic acid,ATRA)联合应用对溃疡性结肠炎小鼠Treg细胞Foxp3蛋白及其相关细胞因子的表达和血钙、肌酐水平的影响.方法 6w龄雌性C57BL/6小鼠50只,随机分为正常对照组(CN),溃疡性结肠炎模型组(model,M),1,25-(OH)2D3干预,全反式视黄酸(ATRA)干预,1,25-(OH) 2D3+ATRA联合干预共5组,除CN组外,其余4组随意饮3%糖酐酯(DSS)溶液建立溃疡性结肠炎模型,从造模D3开始干预,干预剂1,25-(OH)2D3和ATRA分别用花生油溶解(后者需在暗光下进行),干预剂量1,25-(OH)2D3100ng(d/capita),ATRA 0.2 mg(d/capita),1,25-(OH) 2D3+ATRA(100ng/d+0.2mg/d)每天对应灌胃干预,9d后处死小鼠,取血清和结肠组织.按小鼠一般情况进行疾病活动指数(disease activity index,DAI)评分;测量结肠长度;观察结肠大体形态和病理学损伤情况,并对其进行组织病理学评分;生物化学方法检测小鼠结肠髓过氧化物酶(myeloperoxidase,MPO)活性和血清钙、肌酐水平;免疫组化法测结肠组织Foxp3、TGF-β、IL-10蛋白表达情况.结果 与M组比较,三个干预组小鼠溃疡性结肠炎大体形态改善,组织学损伤较轻,结肠长度缩短有所缓解,结肠组织MPO活性下降,Foxp3蛋白及其相关细胞因子TGF-β、IL-10表达水平上升,血钙和肌酐水平下降.且联合干预组相比单独干预组效果更明显,差异具有统计学意义(除血钙).结论 1,25-(OH)2D3和全反式视黄酸(ATRA)联合应用能够增强Treg细胞Foxp3的表达,使Treg细胞更好地发挥抑制免疫应答的作用,并可能缓解1,25-(OH)2D3引起的血钙升高,改善肾功能.

  15. Caspase-3 expression in spinal tissue of retinoic acid induce spiua bifida fetal rat%维甲酸诱导脊柱裂胎鼠脊髓组织中Caspase-3表达情况

    Institute of Scientific and Technical Information of China (English)

    马英桓; 袁正伟

    2012-01-01

    Objective To explore caspase-3 expression in spinal tissue of retinoic acid induced spina bifida fetal rat. Methods Pregnant Wister rats with 10 days were used. Retinoic acid dissolved in olive oil (40mg /ml) were stomach fed for preparing the rat model of spina bifida malformations 135mg / kg). Control group only received olive oil. The animals were divided into 4 groups: pregnancy of 12 days, 15 days, 17 days and 20 days. Immunohistochemical method was used to detect and compare caspase-3 expression in different groups. Results The expression of caspase-3 increased at the day 15 after pregnancy, and maintained until day 20 in the spinal tissue of modeled fetal rat, which presented significant difference compared to that of control groups at the same pregnant time. At day 15, day 17 and day 20 of pregnancy, the number of caspase-3 positive cells was more in model animals than the control. Conclusions Retinoic acid induced spina bifida fetal rat demonstrates the increased caspase-3 expression in spinal tissue of fetal rats.%目的 本文旨在探讨维甲酸诱导脊柱裂胎鼠脊髓组织Caspase-3表达情况.方法 选取孕10d Wistar大鼠,实验组用溶有维甲酸(40mg/ml)的橄榄油,以135mg/kg经胃管注入给药制作脊柱裂畸形大鼠模型;对照组选取孕10 d Wistar大鼠给等量橄榄油.将实验组及对照组按照孕12、15、17和20 d分为4组.应用免疫组织化学方法比较分析Caspase-3在对照组、畸形组胎鼠脊髓组织细胞中的分布和表达情况.结果 脊柱裂大鼠脊髓神经组织中Caspase-3在15d开始增多,一直持续到20 d胚胎大鼠.其增高情况明显高于同一时间点对照组大鼠.胚胎15、17和20 d显性脊柱裂畸形鼠脊髓组织Caspase-3阳性细胞数多于对照组,荧光强度高于对照组.结论 维甲酸诱导的脊柱裂胎鼠Caspase-3表达明显高于正常发育胎鼠.

  16. Triplet State Resonance Raman Spectrum of all-trans-diphenylbutadiene

    DEFF Research Database (Denmark)

    Wilbrandt, Robert Walter; Grossman, W.E.L.; Killough, P.M;

    1984-01-01

    The resonance Raman spectrum of all-trans-diphenylbutadiene (DPB) in its ground state and the resonance Raman spectrum (RRS) of DPB in its short-lived electronically excited triplet state are reported. Transient spectra were obtained by a pump-probe technique using two pulsed lasers. The prereson...

  17. Tgm2/Gh, Gbx1 and TGF-beta are involved in retinoic acid-induced transdifferentiation from epidermis to mucosal epithelium.

    Science.gov (United States)

    Obinata, Akiko; Osakabe, Keitarou; Yamaguchi, Mari; Morimoto, Riyo; Akimoto, Yoshihiro

    2011-01-01

    We previously demonstrated that retinoic acid (RA) induces epidermis to transdifferentiate to mucosal epithelium with goblet cells in chick embryonic cultured skin. To characterize the molecular mechanism of this transdifferentiation process, we used rat embryonic cultured skin and immunohistochemistry to confirm that RA-induced epidermal transdifferentiation accompanies the expression of markers of esophagus epithelium. Because Gbx1, TG2/Gh (transglutaminase2) and TGF-beta2 are reported individually to be induced by RA in cultures of chick embryonic skin, mouse epidermal cells and human hair follicles respectively, here, we investigated whether cooperative interplay of Gbx1, TG2/Gh and TGF-beta2 is required for the transdifferentiation of epidermal cells to mucosal cells. We have shown that expression of Gbx1, TG2/Gh and TGF-beta proteins were all upregulated in RA-induced transdifferentiated skin and that the former two were expressed in the epidermis, while TGF-beta was expressed in the dermis. Inhibitors of the TGF-beta signal pathway partially inhibited transdifferentiation. Overexpression of both hTG2/Gh and mGbx1 together in the epidermis by electroporation resulted in cuboidal cells in the upper cell layers of the epidermis without keratinized layers, although epidermal keratinization was observed in skin by overexpression of either of them. Labeling DNA with BrdU indicated that RA directly transdifferentiated transient amplifying epidermal cells, not stem cells, to mucosal cells. This study showed that coexpression of TG/2 and Gbx1 in the epidermis was required for esophagus-like mucosal transdifferentiation, and that increase in TGF-beta2 expression by RA in the dermis was essential to induce transdifferentiation through epithelial-mesenchymal interaction.

  18. Functional decreases in P2X7 receptors are associated with retinoic acid-induced neuronal differentiation of Neuro-2a neuroblastoma cells.

    Science.gov (United States)

    Wu, Pei-Yu; Lin, Yu-Chia; Chang, Chia-Ling; Lu, Hsing-Tsen; Chin, Chia-Hsuan; Hsu, Tsan-Ting; Chu, Dachen; Sun, Synthia H

    2009-06-01

    Neuro-2a (N2a) cells are derived from spontaneous neuroblastoma of mouse and capable to differentiate into neuronal-like cells. Recently, P2X7 receptor has been shown to sustain growth of human neuroblastoma cells but its role during neuronal differentiation remains unexamined.We characterized the role of P2X7 receptors in the retinoic acid (RA)-differentiated N2a cells. RA induced N2a cells differentiation into neurite bearing and neuronal specific proteins, microtubule-associated protein 2 (MAP2) and neuronal specific nuclear protein (NeuN), expressing neuronal-like cells. Interestingly, the RA-induced neuronal differentiation was associated with decreases in the expression and function of P2X7 receptors. Functional inhibition of P2X7 receptors by P2X7 receptor selective antagonists, 5'-triphosphate, periodate-oxidized 2',3'-dialdehyde ATP (oATP), brilliant blue G (BBG) or A438079 induced neurite outgrowth. In addition, RA and oATP treatment stimulated the expression of neuron-specific class III beta-tubulin (TuJ1), and knockdown of P2X7 receptor expression by siRNA induced neurite outgrowth. To elucidate the possible mechanism, we found the levels of basal intracellular Ca2+ concentrations ([Ca2+]i) were decreased in either RA- or oATP-differentiated or P2X7receptor knockdown N2a cells. Simply cultured N2a cells in low Ca2+ medium induced a 2-fold increase in neurite length. Treatment of N2a cells with ATP hydrolase apyrase and the P2X7 receptors selective antagonist oATP or BBG decreased cell viability and cell number. Nevertheless, oATP but not BBG decreased cell proliferation and cell cycle progression. These results suggest for the first time that decreases in expression/function of P2X7 receptors are involved in neuronal differentiation.We provide additional evidence shown that the ATP release-activated P2X7 receptor is important in maintaining cell survival of N2a neuroblastoma cells.

  19. Cardiac Optogenetics: Enhancement by All-trans-Retinal.

    Science.gov (United States)

    Yu, Jinzhu; Chen, Kay; Lucero, Rachel V; Ambrosi, Christina M; Entcheva, Emilia

    2015-11-16

    All-trans-Retinal (ATR) is a photosensitizer, serving as the chromophore for depolarizing and hyperpolarizing light-sensitive ion channels and pumps (opsins), recently employed as fast optical actuators. In mammalian optogenetic applications (in brain and heart), endogenous ATR availability is not considered a limiting factor, yet it is unclear how ATR modulation may affect the response to optical stimulation. We hypothesized that exogenous ATR may improve light responsiveness of cardiac cells modified by Channelrhodopsin2 (ChR2), hence lowering the optical pacing energy. In virally-transduced (Ad-ChR2(H134R)-eYFP) light-sensitive cardiac syncytium in vitro, ATR supplements ≤2 μM improved cardiomyocyte viability and augmented ChR2 membrane expression several-fold, while >4 μM was toxic. Employing integrated optical actuation (470 nm) and optical mapping, we found that 1-2 μM ATR dramatically reduced optical pacing energy (over 30 times) to several μW/mm(2), lowest values reported to date, but also caused action potential prolongation, minor changes in calcium transients and no change in conduction. Theoretical analysis helped explain ATR-caused reduction of optical excitation threshold in cardiomyocytes. We conclude that cardiomyocytes operate at non-saturating retinal levels, and carefully-dosed exogenous ATR can enhance the performance of ChR2 in cardiac cells and yield energy benefits over orders of magnitude for optogenetic stimulation.

  20. Difference in effect of temperature on absorption and Raman spectra between all-trans-β-carotene and all-trans-retinol

    Institute of Scientific and Technical Information of China (English)

    Qu Guan-Nan; Li Zuo-Wei; Gao Shu-Qin; Li Shuo; Sun Cheng-Lin; Liu Tian-Yuan; Wu Yong-Ling; Sun Shang; Shan Xiao-Ning; Men Zhi-Wei; Chen Wei

    2012-01-01

    Temperature dependencies (81 ℃-18 ℃) of visible absorption and Raman spectra of all-trans-β-carotene and all-trans-retinol extremely diluted in dimethyl sulfoxide are investigated in order to clarify temperature effects on different polyenes.Their absorption spectra are identified to be redshifted with temperature decreasing.Moreover,all-trans-β-carotene is more sensitive to temperature due to the presence of a longer length of conjugated system.The characteristic energy responsible for the conformational changes in all-trans-β-carotene is smaller than that in all-trans-retinol.Both of the Raman scattering cross sections increase with temperature decreasing.The results are explained with electron-phonon coupling theory and coherent weakly damped electron-lattice vibrations model.

  1. Difference in effect of temperature on absorption and Raman spectra between all-trans-β-carotene and all-trans-retinol

    Science.gov (United States)

    Qu, Guan-Nan; Li, Shuo; Sun, Cheng-Lin; Liu, Tian-Yuan; Wu, Yong-Ling; Sun, Shang; Shan, Xiao-Ning; Men, Zhi-Wei; Chen, Wei; Li, Zuo-Wei; Gao, Shu-Qin

    2012-12-01

    Temperature dependencies (81 °C-18 °C) ofvisible absorption and Raman spectra of all-trans-β-carotene and all-trans-retinol extremely diluted in dimethyl sulfoxide are investigated in order to clarify temperature effects on different polyenes. Their absorption spectra are identified to be redshifted with temperature decreasing. Moreover, all-trans-β-carotene is more sensitive to temperature due to the presence of a longer length of conjugated system. The characteristic energy responsible for the conformational changes in all-trans-β-carotene is smaller than that in all-trans-retinol. Both of the Raman scattering cross sections increase with temperature decreasing. The results are explained with electron—phonon coupling theory and coherent weakly damped electron—lattice vibrations model.

  2. Molecular Cloning and Preliminary Functional Analysis of Domains of Duck Retinoic Acid Inducible Gene Ⅰ%鸭维甲酸诱导基因Ⅰ克隆及其结构域功能分析

    Institute of Scientific and Technical Information of China (English)

    陈阳; 黄正洋; 张扬; 李欣钰; 甄霆; 吴宁昭; 徐琪; 陈国宏

    2013-01-01

    [目的]克隆鸭维甲酸诱导基因Ⅰ (retinoic acid inducible gene Ⅰ,RIG-Ⅰ),分析其不同结构域的功能.[方法]根据GenBank上公布的鸭RIG-Ⅰ序列设计引物,利用RT-PCR克隆鸭RIG-Ⅰ基因CDS (coding sequence)区,根据保守结构域预测结果,构建携带6*his组氨酸标签的不同结构域缺失突变体的真核表载体(RIG-Ⅰ-Full、RIG-Ⅰ-N和RIG-Ⅰ-C),转染鸡胚成纤维细胞DF1,经RT-PCR、间接免疫荧光方法鉴定重组质粒在细胞中转录与表达;同时,利用RT-qPCR检测RLR抗病毒信号通路中的IFN-β、Mx1和PKR等下游基因的表达变化.[结果]鸭RIG-Ⅰ基因CDS区全长2802 bp,共编码933个氨基酸;不同结构域缺失突变体的真核表载体转染DF1细胞后,重组蛋白均在DF1细胞中表达;RT-qPCR结果显示,N端能显著激活RLR通路上IFN-β、Mx1及PKR基因的表达上调.[结论]duRIG-Ⅰ及不同区段均能在DF1细胞中表达,其中N端在调节RLR抗病毒信号通路下游基因的表达过程中发挥了重要作用.%[Objective] Duck RIG-Ⅰ (duRIG-Ⅰ) gene was cloned and the functions of its different domains were analyzed preliminarily.[Method] The CDS of duRIG-Ⅰ gene was cloned on the basis of the sequence submitted to GenBank with RT-PCR and was analyzed by bioinformatics.The eukaryotic expression vectors of N-terminal,C-terminal and whole-length of duRIG-Ⅰ gene with 6*his tags were constructed to transfect DF1,and then the transcription and expression of the three recombinant plasmids in cells were detected via RT-PCR and indirect immunofluorescent assay,respectively.Meanwhile,the expressions of chicken IFN-β,Mxl and PKR mRNA were detected by real-time PCR.[Result] The whole-length of duRIG-Ⅰ CDS was 2802 bp encoding 933 amino acids.All the recombinant protein of duRIG-Ⅰ could express normally in DF1.The results of RT-qPCR indicated that CARDs significantly up-regulated the mRNA level of IFN-β,Mx1 and PKR genes.[Conclusion] The various domain

  3. Three Conazoles Increase Hepatic Microsomal Retinoic Acid Metabolism and Decrease Mouse Hepatic Retinoic Acid Levels In Vivo

    Science.gov (United States)

    Conazoles are fungicides used in agriculture and as pharmaceuticals. In a previous toxicogenomic study of triazole-containing conazoles we found gene expression changes consistent with the alteration of the metabolism of all trans-retinoic acid (atRA), a vitamin A metabolite with...

  4. Retinoic acid induces osteogenic differentiation of periodontal ligament stem cells from miniature swine in vitro%维甲酸诱导小型猪牙周膜干细胞的体外成骨

    Institute of Scientific and Technical Information of China (English)

    张鹏涛; 钟良军; 张远; 张源明; 徐艳

    2011-01-01

    BACKGROUND: Recent studies have found that retinoic acid can induce the osteogenic differentiation of embryonic stem cellsand multiple adult stem cells.OBJECTIVE: To observe the effect of retinoic acid on osteogenic differentiation of porcine periodontal ligament stem cellsCPDLSCs).METHOOS: Porcine PDLCs were harvested by using outgrowth method: PDLSCs were isolated by limited dilution of culture cellsfor single cell clone. Immunofluores cence was used to detect the expression of STRO-1 andimmunocytochemistry to detect theexpression of vimentin and pan-Cytokeratin(PCK) of porcine PDLSCs. Cell counting hits (CCIKB)was applied to evaluated Cellproliferation of PDLSCs. The colony formation of porcine PDLSCs ratio was assayed. Third passage PDLSCs were inducedwithmineralized conditional medium containing retinoic acid, ascorbic acid and β-glycerophBphate.Mineralzednodules werestudiedby Alizarin red S staining. Osteopontin. Osteocalcin. Collagen type I and collagen type III were detected byimmunocytochemistry.RESULTS AND CONCLUSION: Porcine PDLSCs expressed STRO-1 and vimentin. And the result of pan-Cytokeratin wasnegative. Porcine PDLSCs colony formation ratio was 2.8%. PDLSCs induced by retinoic acid showed positive expression ofak aline phosphatase at 14 days and positive expression of Alizarin red S at 21 days. Osteopontin. Osteocalon.colagent)pe Iwere positive but collagen type III was negative at21 days. These finding! Indicate that retinoic acid can be an effective inducerof osteogenic differentiation of porcine PDLSCs.%背景:近期研究发现维甲酸对胚胎干细胞及多种成体干细胞具有成骨方向诱导的作用.目的:观察维甲酸对小型猪牙周膜干细胞体外成骨作用的影响.方法:采用组织块法获得小型猪牙周膜细胞,有限稀释法纯化小型猪牙周膜干细胞,免疫荧光法检测STRO-1、免疫细胞化学法检测波形蛋白、角蛋白鉴定小型猪牙周膜干细胞.CCK8法测定小型猪牙周膜干细

  5. Additional chromosome abnormalities in patients with acute promyelocytic leukemia treated with all-trans retinoic acid and chemotherapy

    NARCIS (Netherlands)

    Cervera, Jose; Montesinos, Pau; Hernandez-Rivas, Jesus M.; Calasanz, Maria J.; Aventin, Anna; Ferro, Maria T.; Luno, Elisa; Sanchez, Javier; Vellenga, Edo; Rayon, Chelo; Milone, Gustavo; de la Serna, Javier; Rivas, Concha; Gonzalez, Jose D.; Tormo, Mar; Amutio, Elena; Gonzalez, Marcos; Brunet, Salut; Lowenberg, Bob; Sanz, Miguel A.

    2010-01-01

    Background Acute promyelocytic leukemia is a subtype of acute myeloid leukemia characterized by the t(15;17). The incidence and prognostic significance of additional chromosomal abnormalities in acute promyelocytic leukemia is still a controversial matter. Design and Methods Based on cytogenetic dat

  6. Additional chromosome abnormalities in patients with acute promyelocytic leukemia treated with all-trans retinoic acid and chemotherapy

    NARCIS (Netherlands)

    J. Cervera (José); P. Montesinos (Pau); J.M. Hernandez-Rivas (J. M.); M.J. Calasanz (Maria); A. Aventín (Anna); M.T. Ferro (María); E. Luño (Elisa); J. Sánchez (Javier); E. Vellenga (Edo); C. Rayón (Chelo); G. Milone (Gustavo); J. de Serna (Javier); C. Rivas (Concha); J.D. González (José David); M. Tormo (Mar); E. Amutio (Elena); S. Brunet (Salut); B. Löwenberg (Bob); M.A. Sanz (Miguel Angel)

    2010-01-01

    textabstractBackground: Acute promyelocytic leukemia is a subtype of acute myeloid leukemia characterized by the t(15;17). The incidence and prognostic significance of additional chromosomal abnormalities in acute promyelocytic leukemia is still a controversial matter. Design and Methods: Based on c

  7. Malignancy: Case Report: Acute Promyelocytic Leukemia in Late Pregnancy. Successful Treatment with All-Trans-Retinoic Acid (ATRA) and Chemotherapy.

    Science.gov (United States)

    Delgado-Lamas, JOSÉ LUIS; Garcés-Ruiz, OSCAR MIGUEL

    2000-01-01

    The use of all-transretinoic acid (ATRA) in APL is a great advance in the treatment of acute leukemia, driving the maturation steps until adult form. The effect of this medication in pregnant women with APL is being a safe and effective treatment only after the first trimester of pregnancy. If used in the first three months, it can cause fetus malformations due to its potent teratogenicity. The two patients we reported here, gave birth to normal children, yet they received ATRA. After a week with ATRA treatment, fibrinogen level improved and "D" dimers decreased, so as observed slowly maturation of leukemic leucocytes. ATRA used at the same time with chemotherapy; such as Cytarabine and Idarrubicine seems highly useful for induction and long term control of disease. One short discussion about the findings and compare with those found in the literature are presented.

  8. Acute Promyelocytic Leukemia in Late Pregnancy. Successful Treatment with All-Trans-Retinoic Acid (ATRA) and Chemotherapy.

    Science.gov (United States)

    Delgado-Lamas, J L; GarcéS-Ruiz, O M

    1999-01-01

    The use of all-transretinoic acid (ATRA) in APL is a great advance in the treatment of acute leukemia, driving the maturation steps until adult form. The effect of this medication in pregnant women with APL is being a safe and effective treatment only after the first trimester of pregnancy. If used in the first three months, it can cause fetus malformations due to its potent teratogenicity. The two patients we reported here, gave birth to normal children, yet they received ATRA. After a week with ATRA treatment, fibrinogen level improved and "D" dimers decreased, so as observed slowly maturation of leukemic leucocytes. ATRA used at the same time with chemotherapy; such as Cytarabine and Idarrubicine seems highly useful for induction and long term control of disease. One short discussion about the findings and compare with those found in the literature are presented.

  9. Immunomodulatory effects of testosterone evaluated in all-trans retinoic acid differentiated HL-60 cells, granulocytes, and monocytes

    DEFF Research Database (Denmark)

    Boje, Alex; Moesby, Lise; Timm, Michael;

    2012-01-01

    that testosterone at pharmacological doses reduced the production of interleukin-8 and reactive oxygen species from differentiated HL-60 cells in a concentration dependent manner without affecting phagocytosis. The cells were stimulated with zymosan, lipopolysaccharide, or Bacillus subtilis. At the highest...... concentration of testosterone (120 µM), interleukin-8 secretion was reduced 42-80%, and production of reactive oxygen species was reduced 32-46%. Flutamide, an antagonist of the classical intracellular androgen receptor, was unable to antagonize the immunosuppressive effect of testosterone. We further...

  10. Regulation of neurogenesis and gliogenesis of retinoic acid-induced P19 embryonal carcinoma cells by P2X2 and P2X7 receptors studied by RNA interference.

    Science.gov (United States)

    Yuahasi, Katia K; Demasi, Marcos A; Tamajusuku, Alessandra S K; Lenz, Guido; Sogayar, Mari C; Fornazari, Maynara; Lameu, Claudiana; Nascimento, Isis C; Glaser, Talita; Schwindt, Telma T; Negraes, Priscilla D; Ulrich, Henning

    2012-04-01

    Embryonic carcinoma cells are widely used models for studying the mechanisms of proliferation and differentiation occurring during early embryogenesis. We have now investigated how down-regulation of P2X2 and P2X7 receptor expression by RNA interference (RNAi) affects neural differentiation and phenotype specification of P19 embryonal carcinoma cells. Wild-type P19 embryonal carcinoma cells or cells stably expressing shRNAs targeting P2X2 or P2X7 receptor expression were induced to differentiate into neurons and glial cells in the presence of retinoic acid. Silencing of P2X2 receptor expression along differentiation promoted cell proliferation and an increase in the percentage of cells expressing glial-specific GFAP, while the presence of beta-3 tubulin-positive cells diminished at the same time. Proliferation induction in the presence of stable anti-P2X2 receptor RNAi points at a mechanism where glial proliferation is favored over growth arrest of progenitor cells which would allow neuronal maturation. Differently from the P2X2 receptor, inhibition of P2X7 receptor expression during neural differentiation of P19 cells resulted in a decrease in cell proliferation and GFAP expression, suggesting the need of functional P2X7 receptors for the progress of gliogenesis. The results obtained in this study indicate the importance of purinergic signaling for cell fate determination during neural differentiation, with P2X2 and P2X7 receptors promoting neurogenesis and gliogenesis, respectively. The shRNAs down-regulating P2X2 or P2X7 receptor gene expression, developed during this work, present useful tools for studying mechanisms of neural differentiation in other stem cell models.

  11. 干扰素刺激反应元件Ⅰ/Ⅱ在维甲酸诱导基因G表达调控中的作用%Role of the interferon-stimulated response elements Ⅰ/Ⅱ in expression regulation of the retinoic acid induced gene G

    Institute of Scientific and Technical Information of China (English)

    楼叶江; 潘晓蓉; 贾培敏; 张长林; 许桂平; 李冬; 童建华

    2010-01-01

    Objective To study the regulatory role of interferon-stimulated response elements (ISREs) located on the retinoic acid-induced gene G (RIG-G) promoter in RIG-G expression. Methods By using point mutation technique, the authors constructed the wide type and site-mutant reporter gene plasmids according to the ISRE sequence on RIG-G promoter, and detected the functional activities by luciferase reporter assay. Results Mutation in ISRE Ⅱ alone had no obvious effect on the expression of the reporter gene, whereas mutation in ISRE Ⅰ dramatically inhibited the transactivity of RIG-G promoter. Mutation in both ISRE Ⅰ and ISRE Ⅱ resulted in complete loss of its response to the transcription factors for the reporter gene. Conclusion Both ISRE Ⅰ and ISRE Ⅱ on the RIG-G promoter are the binding sites for the complex of transcription factors. They are required for RIG-G expression, and ISRE Ⅰ has a preferential role over ISRE Ⅱ .%目的 深入研究维甲酸诱导基因G(retinoic acid-induced gene G,RIG-G)启动子上所含的干扰素刺激反应元件(interferon-stimulated response elements,ISRE)对RIG-G基因表达的调控作用.方法 根据RIG-G基因启动子所包含的ISRE序列,利用定点突变技术分别构建野生型和位点突变型的报告基因质粒,然后采用报告基因转染实验检测RIG-G基因启动子中ISRE序列的功能活性.结果 研究发现单独突变RIG-G基因启动子上的ISRE Ⅱ元件不影响报告基因的表达,而单独突变ISRE Ⅰ则会对报告基因的表达产生明显的抑制作用;同时突变ISRE Ⅰ和ISRE Ⅱ元件则会使报告基因完全失去对转录因子的反应性.结论 RIG-G基因启动子所包含的ISRE Ⅰ和ISRE Ⅱ元件是诱导该基因表达的转录因子复合物的作用位点,是该基因表达的分子基础,且ISRE Ⅰ元件的作用要优先于ISRE Ⅱ.

  12. Tuning the Electronic Absorption of Protein-Embedded All-trans-Retinal

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Wenjing [Michigan State Univ., East Lansing, MI (United States); Nossoni, Zahra [Michigan State Univ., East Lansing, MI (United States); Berbasova, Tetyana [Michigan State Univ., East Lansing, MI (United States); Watson, Camille T. [Michigan State Univ., East Lansing, MI (United States); Yapici, Ipek [Michigan State Univ., East Lansing, MI (United States); Lee, Kin Sing Stephen [Michigan State Univ., East Lansing, MI (United States); Vasileiou, Chrysoula [Michigan State Univ., East Lansing, MI (United States); Geiger, James H. [Michigan State Univ., East Lansing, MI (United States); Borhan, Babak [Michigan State Univ., East Lansing, MI (United States)

    2014-10-02

    Protein-chromophore interactions are a central component of a wide variety of critical biological processes such as color vision and photosynthesis. To understand the fundamental elements that contribute to spectral tuning of a chromophore inside the protein cavity, we redesigned human cellular retinol binding protein II (hCRBPII) to fully encapsulate all-trans-retinal and form a covalent bond as a protonated Schiff base. The system, using rational mutagenesis designed to alter the electrostatic environment within the binding pocket of the host protein, enabled regulation of the absorption maximum of the pigment in the range of 425 to 644 nanometers. Moreover, with only nine point mutations, the hCRBPII mutants induced a systematic shift in the absorption profile of all-trans-retinal of more than 200 nanometers across the visible spectrum.

  13. Chronic retinoic acid treatment suppresses adult hippocampal neurogenesis, in close correlation with depressive-like behavior

    NARCIS (Netherlands)

    Hu, Pu; Wang, Yu; Liu, Ji; Meng, Fan-Tao; Qi, Xin-Rui; Chen, Lin; van Dam, Anne-Marie; Joëls, Marian; Lucassen, Paul J; Zhou, Jiang-Ning

    2016-01-01

    Clinical studies have highlighted an association between retinoid treatment and depressive symptoms. As we had shown before that chronic application of all-trans retinoic acid (RA) potently activated the hypothalamus-pituitary-adrenal (HPA) stress axis, we here questioned whether RA also induced cha

  14. The histone demethylase PHF8 governs retinoic acid response in acute promyelocytic leukemia

    DEFF Research Database (Denmark)

    Arteaga, Maria Francisca; Mikesch, Jan-Henrik; Qiu, Jihui

    2013-01-01

    While all-trans retinoic acid (ATRA) treatment in acute promyelocytic leukemia (APL) has been the paradigm of targeted therapy for oncogenic transcription factors, the underlying mechanisms remain largely unknown, and a significant number of patients still relapse and become ATRA resistant. We id...

  15. Role of the retinoic acid receptor-α in HIV-associated nephropathy.

    Science.gov (United States)

    Ratnam, Krishna K; Feng, Xiaobei; Chuang, Peter Y; Verma, Vikram; Lu, Ting-Chi; Wang, Jinshan; Jin, Yuanmeng; Farias, Eduardo F; Napoli, Joseph L; Chen, Nan; Kaufman, Lewis; Takano, Tomoko; D'Agati, Vivette D; Klotman, Paul E; He, John C

    2011-03-01

    All-trans retinoic acid protects against the development of HIV-associated nephropathy (HIVAN) in HIV-1 transgenic mice (Tg26). In vitro, all-trans retinoic acid inhibits HIV-induced podocyte proliferation and restores podocyte differentiation markers by activating its receptor-α (RARα). Here, we report that Am580, a water-soluble RARα-specific agonist, attenuated proteinuria, glomerosclerosis, and podocyte proliferation, and restored podocyte differentiation markers in kidneys of Tg26 mice. Furthermore, RARα-/- Tg26 mice developed more severe kidney and podocyte injury than did RARα+/- Tg26 mice. Am580 failed to ameliorate kidney injury in RARα-/- Tg26 mice, confirming our hypothesis that Am580 acts through RARα. Although the expression of RARα-target genes was suppressed in the kidneys of Tg26 mice and of patients with HIVAN, the expression of RARα in the kidney was not different between patients with HIVAN and minimal change disease. However, the tissue levels of retinoic acid were reduced in the kidney cortex and isolated glomeruli of Tg26 mice. Consistent with this, the expression of two key enzymes in the retinoic acid synthetic pathway, retinol dehydrogenase type 1 and 9, and the overall enzymatic activity for retinoic acid synthesis were significantly reduced in the glomeruli of Tg26 mice. Thus, a defect in the endogenous synthesis of retinoic acid contributes to loss of the protection by retinoic acid in HIVAN. Hence, RARα agonists may be potential agents for the treatment of HIVAN.

  16. Stabilization of all-trans-lycopene from tomato by encapsulation using cyclodextrins

    OpenAIRE

    Blanch, Gracia Patricia; Ruiz del Castillo, Maria Luisa; Caja, Maria del Mar; Pérez-Méndez, Mercedes; Sánchez-Cortés, Santiago

    2007-01-01

    The stabilization of all-trans-lycopene from tomato by encapsulation using a-, b- and c-cyclodextrins (CDs) was evaluated. To that end, two different encapsulation methods were comparatively studied: a conventional method and a supercritical fluid extraction (SFE) process. An optimization procedure considering distinct molar ratios of CD/lycopene (1/0.0026, 1/0.005 and 1/0.05) as well as the type of cyclodextrin to be used was accomplished. The encapsulation was determined by using micro-Rama...

  17. Natural lycopene from Blakeslea trispora: all-trans lycopene thermochemical and structural properties

    Energy Technology Data Exchange (ETDEWEB)

    Estrella, A.; Lopez-Ortiz, J.F.; Cabri, W.; Rodriguez-Otero, C.; Fraile, N.; Erbez, A.J.; Espartero, J.L.; Carmona-Cuenca, I.; Chaves, E.; Munoz-Ruiz, A

    2004-07-09

    Structural and thermal properties of all-trans lycopene are described in the present paper. Different crystalline lycopene samples obtained from fermentation process and recrystallized lycopene were analyzed. Structural properties (NMR, mass spectrometry and powder X-ray diffraction) of lycopene were clarified with recent techniques. High purity sample analysis by differential scanning calorimetry was used to study thermal behavior of pure lycopene and with traces of isomers. But also this was correlated with HPLC method for determine lycopene purity and isomers in low proportion.

  18. Optimization of extraction of high purity all-trans-lycopene from tomato pulp waste.

    Science.gov (United States)

    Poojary, Mahesha M; Passamonti, Paolo

    2015-12-01

    The aim of this work was to optimize the extraction of pure all-trans-lycopene from the pulp fractions of tomato processing waste. A full factorial design (FFD) consisting of four independent variables including extraction temperature (30-50 °C), time (1-60 min), percentage of acetone in n-hexane (25-75%, v/v) and solvent volume (10-30 ml) was used to investigate the effects of process variables on the extraction. The absolute amount of lycopene present in the pulp waste was found to be 0.038 mg/g. The optimal conditions for extraction were as follows: extraction temperature 20 °C, time 40 min, a solvent composition of 25% acetone in n-hexane (v/v) and solvent volume 40 ml. Under these conditions, the maximal recovery of lycopene was 94.7%. The HPLC-DAD analysis demonstrated that, lycopene was obtained in the all-trans-configuration at a very high purity grade of 98.3% while the amount of cis-isomers and other carotenoids were limited.

  19. DMRG-CASPT2 study of the longitudinal static second hyperpolarizability of all-trans polyenes

    CERN Document Server

    Wouters, Sebastian; Van Neck, Dimitri

    2016-01-01

    We have implemented internally contracted complete active space second order perturbation theory (CASPT2) with the density matrix renormalization group (DMRG) as active space solver [Y. Kurashige and T. Yanai, J. Chem. Phys. 135, 094104 (2011)]. Internally contracted CASPT2 requires to contract the generalized Fock matrix with the 4-particle reduced density matrix (4-RDM) of the reference wavefunction. The required 4-RDM elements can be obtained from 3-particle reduced density matrices (3-RDM) of different wavefunctions, formed by symmetry-conserving single-particle excitations op top of the reference wavefunction. In our spin-adapted DMRG code chemps2 [https://github.com/sebwouters/chemps2], we decompose these excited wavefunctions as spin-adapted matrix product states, and calculate their 3-RDM in order to obtain the required contraction of the generalized Fock matrix with the 4-RDM of the reference wavefunction. In this work, we study the longitudinal static second hyperpolarizability of all-trans polyenes...

  20. Retinoic acid primes human dendritic cells to induce gut-homing, IL-10-producing regulatory T cells

    NARCIS (Netherlands)

    Bakdash, G.; Vogelpoel, L.T.; Capel, T.M. van; Kapsenberg, M.L.; Jong, E.C. de

    2015-01-01

    The vitamin A metabolite all-trans retinoic acid (RA) is an important determinant of intestinal immunity. RA primes dendritic cells (DCs) to express CD103 and produce RA themselves, which induces the gut-homing receptors alpha4beta7 and CCR9 on T cells and amplifies transforming growth factor (TGF)-

  1. 反式维甲酸诱导显性脊柱裂胎鼠骶尾部神经前体细胞凋亡和增殖的变化规律研究%Disturbed apoptosis and cell proliferation in developing neuroepithelium of lumbo-sacral neural tubes in retinoic acid-induced spina biifda aperta in rat

    Institute of Scientific and Technical Information of China (English)

    魏晓伟; 袁正伟

    2015-01-01

    目的观察大鼠胚胎脊柱裂发生早期,细胞凋亡与细胞增殖的变化规律。方法孕鼠随机分为对照组和实验组。胚胎10天时,实验组1次性经胃管注入致畸量反式维甲酸诱导产生脊柱裂动物模型,对照组胃饲等量溶剂,分别在妊娠11、12、13天(E11, E12, E13)时剖宫取胚胎,一部分胚胎固定后进行全胚胎TUNEL染色观察其整体凋亡情况;另一部分胚胎常规制作石蜡切片,采用TUNEL切片染色和免疫荧光染色技术,检测胚胎脊部神经管组织中细胞凋亡和细胞增殖的变化。结果与对照组相比,细胞凋亡于多个发育部位明显增多,集中表现在颅面原基、颅部神经管的背外侧、骶尾部神经管的背部中线。免疫荧光染色显示,与对照组相比,脊柱裂组胚胎畸形发生部位的神经前体细胞的凋亡率升高[E11(2.02±0.52)%与(0.57±0.23)%, E12(3.56±0.33)%与(0.93±0.14)%,E13(3.76±0.37)%与(1.24±0.21)%,P<0.001]。而细胞增殖降低[E11(65.17±2.30)%与(81.76±2.17)%, E12(63.97±3.03)%与(76.98±5.14)%,E13(56.86±2.80)%与(73.43±1.99)%,P <0.001]。结论反式维甲酸诱导的大鼠脊柱裂胚胎骶尾部神经管中神经前体细胞凋亡增多,而细胞增殖减少,这可能是脊柱裂胚胎神经元发育异常的主要原因之一。%Objective To investigate the cell apoptosis in the whole embryosand proliferation of neural progenitor cells in the spinal neural tube during neurulation in all-trans retinoic acid (atRA)-induced spina biifda in fetal rats.MethodSpina biifda was induced by atRA in fetal rats. Cell apoptosis and cell proliferation were assessed using TUNEL labeling technique on both whole-mount and serially sectioned embryos and mitotic markers (Ki67) assay, respectively.ResultsAn excess of apoptosis in the neuroepithelium of embryos with spina bifida was found, which became more marked as embryos

  2. Unbinding of Retinoic Acid from its Receptor Studied by Steered Molecular Dynamics

    CERN Document Server

    Kosztin, D; Schulten, K; Kosztin, Dorina; Izrailev, Sergei; Schulten, Klaus

    1999-01-01

    Retinoic acid receptor (RAR) is a ligand-dependent transcription factor that regulates the expression of genes involved in cell growth, differentiation, and development. Binding of the retinoic acid hormone to RAR is accompanied by conformational changes in the protein which induce transactivation or transrepression of the target genes. In this paper we present a study of the hormone binding/unbinding process in order to clarify the role of some of the amino acid contacts and identify possible pathways of the all-trans retinoic acid binding/unbinding to/from human retinoic acid receptor (hRAR)-g. Three possible pathways were explored using steered molecular dynamics simulations. Unbinding was induced on a time scale of 1 ns by applying external forces to the hormone. The simulations suggest that the hormone may employ one pathway for binding and an alternative "back door" pathway for unbinding.

  3. DMRG-CASPT2 study of the longitudinal static second hyperpolarizability of all-trans polyenes

    Science.gov (United States)

    Wouters, Sebastian; Van Speybroeck, Veronique; Van Neck, Dimitri

    2016-08-01

    We have implemented internally contracted complete active space second order perturbation theory (CASPT2) with the density matrix renormalization group (DMRG) as active space solver [Y. Kurashige and T. Yanai, J. Chem. Phys. 135, 094104 (2011)]. Internally contracted CASPT2 requires to contract the generalized Fock matrix with the 4-particle reduced density matrix (4-RDM) of the reference wavefunction. The required 4-RDM elements can be obtained from 3-particle reduced density matrices (3-RDM) of different wavefunctions, formed by symmetry-conserving single-particle excitations op top of the reference wavefunction. In our spin-adapted DMRG code chemps2 https://github.com/sebwouters/chemps2, we decompose these excited wavefunctions as spin-adapted matrix product states and calculate their 3-RDM in order to obtain the required contraction of the generalized Fock matrix with the 4-RDM of the reference wavefunction. In this work, we study the longitudinal static second hyperpolarizability of all-trans polyenes C2nH2n+2 [n = 4-12] in the cc-pVDZ basis set. DMRG-SCF and DMRG-CASPT2 yield substantially lower values and scaling with system size compared to RHF and MP2, respectively.

  4. The photophysics of all-trans polyenes from ttbP5, a nonphotolabile pentaene

    Science.gov (United States)

    Catalán, Javier; Pérez, Pilar; Hopf, Henning; Klein, Dagmar

    2008-07-01

    The all-trans pentaene, 3,12-di(tert-butyl)-2,2,13,13-tetramethyl-3,5,7,9,11-tetradecapentaene (ttbP5) fluoresces in two different regions of the visible spectrum. It produces an extremely weak emission in the gas phase that can also be detected in the condensed phase; such an emission exhibits a negligible Stokes shift with respect to the 1Ag→1Bu absorption transition and can in principle be assigned to the 1Bu→1Ag emission of the compound. ttbP5 also exhibits a second fluorescence emission at approximately 520nm in both the gas phase and the condensed phase. The emission in the condensed phase increases in strength and structure, with no change in spectral position, as the solvent viscosity increases by effect of the solution temperature being lowered. The spectral behavior of this pentaene (ttbP5) is different enough from that reported [J. Catalán et al., J. Chem. Phys. 128, 104504 (2008)] for its tetraene counterpart (ttbP4) to warrant a separate analysis in order to facilitate a better understanding of the way the photophysics of these polyenes changes as their chain is lengthened.

  5. Targeting excited states in all-trans polyenes with electron-pair states

    Science.gov (United States)

    Boguslawski, Katharina

    2016-12-01

    Wavefunctions restricted to electron pair states are promising models for strongly correlated systems. Specifically, the pair Coupled Cluster Doubles (pCCD) ansatz allows us to accurately describe bond dissociation processes and heavy-element containing compounds with multiple quasi-degenerate single-particle states. Here, we extend the pCCD method to model excited states using the equation of motion (EOM) formalism. As the cluster operator of pCCD is restricted to electron-pair excitations, EOM-pCCD allows us to target excited electron-pair states only. To model singly excited states within EOM-pCCD, we modify the configuration interaction ansatz of EOM-pCCD to contain also single excitations. Our proposed model represents a simple and cost-effective alternative to conventional EOM-CC methods to study singly excited electronic states. The performance of the excited state models is assessed against the lowest-lying excited states of the uranyl cation and the two lowest-lying excited states of all-trans polyenes. Our numerical results suggest that EOM-pCCD including single excitations is a good starting point to target singly excited states.

  6. The large 1 1Ag - 2 1Ag C=C stretching vibronic interaction in all-trans polyenes

    NARCIS (Netherlands)

    Buma, W.J.; Zerbetto, F.

    1998-01-01

    An ab initio theoretical approach at several levels of theory is employed to calculate the 11Ag--21Ag- (non)adiabatic vibronic couplings induced by the completely in-phase C=C and C-C bond stretching vibrations of five all-trans polyenes (from butadiene to dodecahexaene). The nonadiabatic couplings

  7. Causes and prognostic factors of remission induction failure in patients with acute promyelocytic leukemia treated with all-trans retinoic acid and idarubicin

    NARCIS (Netherlands)

    J. de Serna (Javier); P. Montesinos (Pau); E. Vellenga (Edo); C. Rayón (Chelo); R. Parody (Ricardo); A. León (Angel); J. Esteve (Jordi); J.M. Bergua (Juan Miguel); G. Milone (Gustavo); G. Debén (Guillermo); C. Rivas (Concha); M. González (Marcos); M. Tormo (Mar); J. Díaz-Mediavilla (Joaquín); J.D. González (Jose); S. Negri (Silvia); E. Amutio (Elena); S. Brunet (Salut); B. Löwenberg (Bob); M.A. Sanz (Miguel Angel)

    2008-01-01

    textabstractAn understanding of the prognostic factors associated with the various forms of induction mortality in patients with acute promyelocytic leukemia (APL) has remained remarkably limited. This study reports the incidence, time of occurrence, and prognostic factors of the major categories of

  8. Causes and prognostic factors of remission induction failure in patients with acute promyelocytic leukemia treated with all-trans retinoic acid and idarubicin

    NARCIS (Netherlands)

    de la Serna, Javier; Montesinos, Pau; Vellenga, Edo; Rayon, Chelo; Parody, Ricardo; Leon, Angel; Esteve, Jordi; Bergua, Juan M.; Milone, Gustavo; Deben, Guillermo; Rivas, Concha; Gonzalez, Marcos; Tormo, Mar; Diaz-Mediavilla, Joaquin; Gonzalez, Jose D.; Negri, Silvia; Amutio, Elena; Brunet, Salut; Lowenberg, Bob; Sanz, Miguel A.

    2008-01-01

    An understanding of the prognostic factors associated with the various forms of induction mortality in patients with acute promyelocytic leukemia (APL) has remained remarkably limited. This study reports the incidence, time of occurrence, and prognostic factors of the major categories of induction f

  9. Fucoidan enhances the therapeutic potential of arsenic trioxide and all-trans retinoic acid in acute promyelocytic leukemia, in vitro and in vivo

    Science.gov (United States)

    Atashrazm, Farzaneh; Lowenthal, Ray M.; Dickinson, Joanne L.; Holloway, Adele F.; Woods, Gregory M.

    2016-01-01

    The morbidity and mortality associated with current therapies for acute promyelocytic leukemia (APL) remain a significant clinical concern, despite improvements in patient survival. Consequently, the development of adjuvant therapies that increase efficacy while reducing morbidities is important. Reducing the concentration of the toxic drugs in adjuvant therapy has the potential to reduce unwanted side effects. Therefore, this study aimed to determine the synergistic effects of fucoidan, an anti-tumor agent, with current APL therapies. When the human APL cell line, NB4, was treated in vitro with fucoidan plus ATO and ATRA at therapeutic and sub-therapeutic doses, there was an increase in sub-G0/G1 cells, annexin V/PI-positive-apoptotic cells and DNA fragmentation. This reduction in proliferation and increase in apoptosis was accompanied by enhanced myeloid differentiation as indicated by an increased expression of CD11b. This was not observed with the AML cell line Kasumi-1, suggesting specificity for APL. In vivo treatment of APL-bearing mice with fucoidan+ATRA or fucoidan+ATO delayed tumor growth, induced differentiation and increased tumor volume doubling time. The differentiated APL cells derived from the excised tumor mass exhibited decreased CD44 expression in fucoidan+ATRA treated mice. This could translate to decreased cell migration in APL patients. Our findings provide evidence supporting the use of fucoidan as an adjuvant therapeutic agent in the treatment of APL. PMID:27329592

  10. Prediction of in vivo developmental toxicity of all-trans-retinoic acid based on in vitro toxicity data and in silico physiologycally based kinetic modeling

    NARCIS (Netherlands)

    Louisse, J.; Bosgra, S.; Blaauboer, B.J.; Rietjens, I.; Verwei, M.

    2015-01-01

    The use of laboratory animals for toxicity testing in chemical safety assessment meets increasing ethical, economic and legislative constraints. The development, validation and application of reliable alternatives for in vivo toxicity testing are therefore urgently needed. In order to use toxicity d

  11. Prediction of in vivo developmental toxicity of all-trans-retinoic acid based on in vitro toxicity data and in silico physiologically based kinetic modeling

    NARCIS (Netherlands)

    Louisse, Jochem; Bosgra, Sieto; Blaauboer, Bas J.; Rietjens, Ivonne M. C. M.; Verwei, Miriam

    2015-01-01

    The use of laboratory animals for toxicity testing in chemical safety assessment meets increasing ethical, economic and legislative constraints. The development, validation and application of reliable alternatives for in vivo toxicity testing are therefore urgently needed. In order to use toxicity d

  12. Fucoidan enhances the therapeutic potential of arsenic trioxide and all-trans retinoic acid in acute promyelocytic leukemia, in vitro and in vivo.

    Science.gov (United States)

    Atashrazm, Farzaneh; Lowenthal, Ray M; Dickinson, Joanne L; Holloway, Adele F; Woods, Gregory M

    2016-07-19

    The morbidity and mortality associated with current therapies for acute promyelocytic leukemia (APL) remain a significant clinical concern, despite improvements in patient survival. Consequently, the development of adjuvant therapies that increase efficacy while reducing morbidities is important. Reducing the concentration of the toxic drugs in adjuvant therapy has the potential to reduce unwanted side effects. Therefore, this study aimed to determine the synergistic effects of fucoidan, an anti-tumor agent, with current APL therapies.When the human APL cell line, NB4, was treated in vitro with fucoidan plus ATO and ATRA at therapeutic and sub-therapeutic doses, there was an increase in sub-G0/G1 cells, annexin V/PI-positive-apoptotic cells and DNA fragmentation. This reduction in proliferation and increase in apoptosis was accompanied by enhanced myeloid differentiation as indicated by an increased expression of CD11b. This was not observed with the AML cell line Kasumi-1, suggesting specificity for APL.In vivo treatment of APL-bearing mice with fucoidan+ATRA or fucoidan+ATO delayed tumor growth, induced differentiation and increased tumor volume doubling time. The differentiated APL cells derived from the excised tumor mass exhibited decreased CD44 expression in fucoidan+ATRA treated mice. This could translate to decreased cell migration in APL patients.Our findings provide evidence supporting the use of fucoidan as an adjuvant therapeutic agent in the treatment of APL.

  13. New contributions to the photophysical model for all-trans-polyenes from ttbP4, a nonphotolabile octatetraene

    Science.gov (United States)

    Catalán, Javier; Hopf, Henning; Martus, Mainrad

    2008-03-01

    All-trans-octatetraene 3,10-di(tert-butyl)-2,2,11,11-tetramethyl-3,5,7,9-dodecatetraene emits fluorescence in three different regions of the visible spectrum. Thus, it produces an extremely weak emission in the gas phase that can hardly be detected in the condensed phase; such an emission exhibits a negligible Stokes shift with respect to the 1Ag→1Bu absorption transition and can, in principle, be assigned to the 1Bu→1Ag emission for the compound. A second, structureless fluorescence emission, centered in the region of 525nm, is observed in the gas phase and at somewhat higher wavelengths in the condensed phase [viz., 570nm in 2-methylbutane (2MB) and 550nm in squalane (SQ)]. While detectable, this emission increases significantly, with no change in spectral position, as the solution temperature is lowered; also, it is abruptly replaced by a new, strongly blueshifted emission at ˜490nm in 2MB and 455mm in SQ when the viscosity of the medium exceeds a given level. The fact that the two fluorescence emissions considerably depart from the expected behavior for a 1Bu→1Ag emission in an all-trans-polyene, and that one disappears while the other simultaneously appears as the medium becomes more rigid, suggests that the two emissions are produced by two different molecular structures and that the rigidity of the medium switches their production from the originally excited all-trans 1Bu form. The observed spectral behavior is consistent with a recently proposed model [J. Catalan, Chem. Phys. 335, 69 (2007)] in which the 1Bu excited state of octatetraene can give two distinct molecular conformers as a result of twisting about different C-C single bonds.

  14. Solid Lipid Nanoparticles Loaded with Retinoic Acid and Lauric Acid as an Alternative for Topical Treatment of Acne Vulgaris.

    Science.gov (United States)

    Silva, Elton Luiz; Carneiro, Guilherme; De Araújo, Lidiane Advíncula; Trindade, Mariana de Jesus Vaz; Yoshida, Maria Irene; Oréfice, Rodrigo Lambert; Farias, Luis de Macêdo; De Carvalho, Maria Auxiliadora Roque; Dos Santos, Simone Gonçalves; Goulart, Gisele Assis Castro; Alves, Ricardo José; Ferreira, Lucas Antônio Miranda

    2015-01-01

    Topical therapy is the first choice for the treatment of mild to moderate acne and all-trans retinoic acid is one of the most used drugs. The combination of retinoids and antimicrobials is an innovative approach for acne therapy. Recently, lauric acid, a saturated fatty acid, has shown strong antimicrobial activity against Propionibacterium acnes. However, topical application of retinoic acid is followed by high incidence of side-effects, including erythema and irritation. Solid lipid nanoparticles represent an alternative to overcome these side-effects. This work aims to develop solid lipid nanoparticles loaded with retinoic acid and lauric acid and evaluate their antibacterial activity. The influence of lipophilic stearylamine on the characteristics of solid lipid nanoparticles was investigated. Solid lipid nanoparticles were characterized for size, zeta potential, encapsulation efficiency, differential scanning calorimetry and X-ray diffraction. The in vitro inhibitory activity of retinoic acid-lauric acid-loaded solid lipid nanoparticles was evaluated against Propionibacterium acnes, Staphylococcus aureus and Staphylococcus epidermidis. High encapsulation efficiency was obtained at initial time (94 ± 7% and 100 ± 4% for retinoic acid and lauric acid, respectively) and it was demonstrated that lauric acid-loaded-solid lipid nanoparticles provided the incorporation of retinoic acid. However, the presence of stearylamine is necessary to ensure stability of encapsulation. Moreover, retinoic acid-lauric acid-loaded solid lipid nanoparticles showed growth inhibitory activity against Staphylococcus epidermidis, Propionibacterium acnes and Staphylococcus aureus, representing an interesting alternative for the topical therapy of acne vulgaris.

  15. Femtosecond time-resolved difference absorption spectroscopy of all-trans-β-Apo-8′-carotenal

    Institute of Scientific and Technical Information of China (English)

    ZHANG Lei; QUAN Donghui; WANG Li; YANG Guozhen; WENG Yuxiang

    2004-01-01

    The femtosecond time-resolved difference absorption spectra of all-trans-βApo-8′-carotenal have been recorded and analyzed by the singular-value decomposition (SVD) method followed by global fitting using a sequential model for the excited-state energy relaxation. With this model, we have obtained the excited-state absorption spectra and the lifetimes of the corresponding excited states both in nonpolar solvent n-hexane and polar solvent methanol. Three excited states, namely S3(170fs), S2(2.32ps) and S1(26ps) in n-hexane, and two excited states S2 (190fs) and S1(9.4ps) in methanol have been observed. The excited-state absorption spectra of all-trans-β-Apo-8′-carotenal in methanol display a red shift and broadeness, while the lifetime of S1 state becomes shorter. It is proposed that these effects are related to the presence of a carbonyl functional group that leads to the solvent effect on the excited-state energy level. At the same time, it is shown that the SVD method is a useful tool in resolving the time-resolved absorption spectra.

  16. Solid-state nanoparticle coated emulsions for encapsulation and improving the chemical stability of all-trans-retinol.

    Science.gov (United States)

    Ghouchi-Eskandar, Nasrin; Simovic, Spomenka; Prestidge, Clive A

    2012-02-28

    Submicron oil-in-water (o/w) emulsions stabilised with conventional surfactants and silica nanoparticles were prepared and freeze-dried to obtain free-flowing powders with good redispersibility and a three-dimensional porous matrix structure. Solid-state emulsions were characterised for visual appearance, particle size distribution, zeta potential and reconstitution properties after freeze-drying with various sugars and at a range of sugar to oil ratios. Comparative degradation kinetics of all-trans-retinol from freeze-dried and liquid emulsions was investigated as a function of storage temperatures. Optimum stability was observed for silica-coated oleylamine emulsions at 4 °C in their wet state. The half-life of all-trans-retinol was 25.66 and 22.08 weeks for silica incorporation from the oil and water phases respectively. This was ∼4 times higher compared to the equivalent solid-state emulsions with drug half-life of 6.18 and 6.06 weeks at 4 °C. Exceptionally, at a storage temperature of 40 °C, the chemical stability of the drug was 3 times higher in the solid-state compared to the wet emulsions which confirmed that freeze-drying is a promising approach to improve the chemical stability of water-labile compounds provided that the storage conditions are optimised.

  17. Influence of the ordered structure of short-chain polymer molecule all-trans-β-carotene on Raman scattering cross section in liquid

    Institute of Scientific and Technical Information of China (English)

    Qu Guan-Nan; OuYang Shun-Li; Wang Wei-Wei; Li Zuo-Wei; Sun Cheng-Lin; Men Zhi-Wei

    2011-01-01

    We measured the resonant Raman spectra of all-trans-β-carotene in solvents with different densities and concentrations at different temperatures. The results demonstrated that the Raman scattering cross section (RSCS) of short-chain polymer all-trans-β-carotene is extremely high in liquid. Resonance and strong coherent weakly damped CC bond vibrating properties play important roles under these conditions. Coherent weakly damped CC bond vibration strength is associated with molecular ordered structure. All-trans-β-carotene has highly ordered structure and strong coherent weakly damped CC bond vibrating properties, which lead to large RSCS in the solvent with large density and low concentration at low temperature.

  18. Fatty acids attached to all-trans-astaxanthin alter its cis-trans equilibrium, and consequently its stability, upon light-accelerated autoxidation

    NARCIS (Netherlands)

    Bruijn, De Wouter J.C.; Weesepoel, Y.; Vincken, J.P.; Gruppen, H.

    2016-01-01

    Fatty acid esterification, common in naturally occurring astaxanthin, has been suggested to influence both colour stability and degradation of all-trans-astaxanthin. Therefore, astaxanthin stability was studied as influenced by monoesterification and diesterification with palmitate. Increased est

  19. Neutrophils are immune cells preferentially targeted by retinoic acid in elderly subjects

    Directory of Open Access Journals (Sweden)

    Minet-Quinard Régine

    2010-08-01

    Full Text Available Abstract Background The immune system gradually deteriorates with age and nutritional status is a major factor in immunosenescence. Of the many nutritional factors implicated in age-related immune dysfunction, vitamin A may be a good candidate, since vitamin A concentrations classically decrease during aging whereas it may possess important immunomodulatory properties via its active metabolites, the retinoic acids. This prompted us to investigate the immune response induced by retinoids in adults and elderly healthy subjects. Before and after oral supplementation with 13cis retinoic acid (0.5 mg/kg/day during 28 days, whole blood cells were phenotyped, and functions of peripheral blood mononuclear cells (PBMC and polymorphonuclear cells (PMN were investigated by flow cytometry and ELISA tests. Results In both young adults (n = 20, 25 ± 4 years and older subjects (n = 20, 65 ± 4 years, retinoic acid supplementation had no effect on the distribution of leukocyte subpopulations or on the functions of PBMC (Il-2 and sIl-2R production, membrane expression of CD25. Concerning PMN, retinoic acid induced an increase in both spontaneous migration and cell surface expression of CD11b in the two different age populations, whereas bactericidal activity and phagocytosis remained unchanged. Conclusions We demonstrated that retinoic acid induces the same intensity of immune response between adult and older subjects, and more specifically affects PMN functions, i.e. adhesion and migration, than PBMC functions.

  20. 9-顺-维A酸诱导肺鳞、腺癌细胞株凋亡与CyclinD1和Rb基因表达的关系%Relationship between Cyclin D1,Rb gene expression and 9-cis-retinoic acid-induced apoptosis in human lung carcinoma cell lines

    Institute of Scientific and Technical Information of China (English)

    游庆军; 沈振亚; 金小寅; 蒋锡初; 于雪艳; 胡国强

    2003-01-01

    目的探讨9-顺-维A酸(9-cis-retinoic acid 9-cis RA)诱导肺癌细胞株凋亡作用及其与Cyclin D1、Rb基因表达的关系.方法体外培养肺鳞癌细胞株L78、肺腺癌细胞株PG,随机分为两组,实验组加9-cis RA使其终浓度为5?μmol/L,对照组加入二甲亚砜使其终浓度为0.1%,培养48?h后用流式细胞仪技术分别检测Cyclin D1、Rb基因表达率,同时用DNA凋亡分析法检测肿瘤细胞凋亡发生率,研究三者之间的相关关系.结果 L78、PG细胞实验组中细胞凋亡发生率显著增高,两株细胞中凋亡发生率与Cyclin D1基因表达率之间负相关(L78:r=-0.707,P<0.05;PG:r=-0.785,P<0.01),与Rb基因表达率之间明显正相关(L78:r=0.743,P<0.01;PG:r=0.755,P<0.01).结论 9-cis RA可能通过Rb基因表达增加和Cyclin D1基因表达减少途径使L78、PG细胞明显阻滞在G0/G1期,并诱导肺癌细胞凋亡.

  1. Development of novel silicon-containing inverse agonists of retinoic acid receptor-related orphan receptors.

    Science.gov (United States)

    Toyama, Hirozumi; Nakamura, Masaharu; Nakamura, Masahiko; Matsumoto, Yotaro; Nakagomi, Madoka; Hashimoto, Yuichi

    2014-03-15

    Retinoic acid receptor (RAR)-related orphan receptors (RORs) regulate a variety of physiological processes, including hepatic gluconeogenesis, lipid metabolism, circadian rhythm and immune function. The RAR agonist: all-trans retinoic acid was reported to be an RORβ inverse agonist, but no information is available regarding ROR activity of its synthetic analogue Am580. Therefore, we screened Am580 and some related tetramethyltetrahydronaphthalene derivatives and carried out structural development studies, including substitution of carbon atoms with silicon, with the aim of creating a potent ROR transcriptional inhibitor. The phenyl amide disila compound 22 showed the most potent ROR-inhibitory activity among the compounds examined. Its activity towards RORα, RORβ and RORγ was increased compared to that of Am580. The IC₅₀ values for RORα, RORβ and RORγ are 1.3, >10 and 4.5 μM, respectively.

  2. Prevention and Reversal of Diabetes by All-Trans Retinoid Acid and Exendin-4 in NOD Mice

    Directory of Open Access Journals (Sweden)

    Jyuhn-Huarng Juang

    2014-01-01

    Full Text Available It has been shown that all-trans retinoid acid (ATRA hinders the development of autoimmune diabetes by inducing immune tolerance status. Meanwhile, exendin-4 increases beta-cell function and mass. Thus, we hypothesized that ATRA and exendin-4 combination therapy would prevent and reverse autoimmune diabetes. NOD/scid mice were intravenously transferred with splenocytes isolated from 12-week-old female NOD mice. After adoptive transfer, mice were treated with vehicle, ATRA (0.5 mg/mouse intraperitoneally every other day, exendin-4 (3 μg/kg subcutaneously twice daily, or combination for 6 weeks. Compared with vehicle, ATRA (P=0.022 and ATRA plus exendin-4 (P=0.013 treatment delayed the onset of diabetes. The pancreatic insulin content in mice treated with ATRA (P=0.013 and exendin-4 (P<0.02 was significantly higher than that of control mice. All but one spontaneous diabetic NOD mouse treated with ATRA and/or exendin-4 remained persistent hyperglycemic. ATRA and/or exendin-4 treatment did not alter their blood glucose levels and survival. Our results indicate that, before the onset of autoimmune diabetes, ATRA and exendin-4 treatment alone preserves pancreatic beta cells; ATRA and ATRA plus exendin-4 treatment delays the onset of autoimmune diabetes. However, after the onset of autoimmune diabetes, ATRA and/or exendin-4 treatment is unable to reverse hyperglycemia or improve survival.

  3. Phloroglucinol protects retinal pigment epithelium and photoreceptor against all-trans-retinal-induced toxicity and inhibits A2E formation.

    Science.gov (United States)

    Cia, David; Cubizolle, Aurélie; Crauste, Céline; Jacquemot, Nathalie; Guillou, Laurent; Vigor, Claire; Angebault, Claire; Hamel, Christian P; Vercauteren, Joseph; Brabet, Philippe

    2016-09-01

    Among retinal macular diseases, the juvenile recessive Stargardt disease and the age-related degenerative disease arise from carbonyl and oxidative stresses (COS). Both stresses originate from an accumulation of all-trans-retinal (atRAL) and are involved in bisretinoid formation by condensation of atRAL with phosphatidylethanolamine (carbonyl stress) in the photoreceptor and its transformation into lipofuscin bisretinoids (oxidative stress) in the retinal pigment epithelium (RPE). As atRAL and bisretinoid accumulation contribute to RPE and photoreceptor cell death, our goal is to select powerful chemical inhibitors of COS. Here, we describe that phloroglucinol, a natural phenolic compound having anti-COS properties, protects both rat RPE and mouse photoreceptor primary cultures from atRAL-induced cell death and reduces hydrogen peroxide (H2 O2 )-induced damage in RPE in a dose-dependent manner. Mechanistic analyses demonstrate that the protective effect encompasses decrease in atRAL-induced intracellular reactive oxygen species and free atRAL levels. Moreover, we show that phloroglucinol reacts with atRAL to form a chromene adduct which prevents bisretinoid A2E synthesis in vitro. Taken together, these data show that the protective effect of phloroglucinol correlates with its ability to trap atRAL and to prevent its further transformation into deleterious bisretinoids. Phloroglucinol might be a good basis to develop efficient therapeutic derivatives in the treatment of retinal macular diseases.

  4. Novel retinoic acid receptor alpha agonists for treatment of kidney disease.

    Directory of Open Access Journals (Sweden)

    Yifei Zhong

    Full Text Available Development of pharmacologic agents that protect podocytes from injury is a critical strategy for the treatment of kidney glomerular diseases. Retinoic acid reduces proteinuria and glomerulosclerosis in multiple animal models of kidney diseases. However, clinical studies are limited because of significant side effects of retinoic acid. Animal studies suggest that all trans retinoic acid (ATRA attenuates proteinuria by protecting podocytes from injury. The physiological actions of ATRA are mediated by binding to all three isoforms of the nuclear retinoic acid receptors (RARs: RARα, RARβ, and RARγ. We have previously shown that ATRA exerts its renal protective effects mainly through the agonism of RARα. Here, we designed and synthesized a novel boron-containing derivative of the RARα-specific agonist Am580. This new derivative, BD4, binds to RARα receptor specifically and is predicted to have less toxicity based on its structure. We confirmed experimentally that BD4 binds to RARα with a higher affinity and exhibits less cellular toxicity than Am580 and ATRA. BD4 induces the expression of podocyte differentiation markers (synaptopodin, nephrin, and WT-1 in cultured podocytes. Finally, we confirmed that BD4 reduces proteinuria and improves kidney injury in HIV-1 transgenic mice, a model for HIV-associated nephropathy (HIVAN. Mice treated with BD4 did not develop any obvious toxicity or side effect. Our data suggest that BD4 is a novel RARα agonist, which could be used as a potential therapy for patients with kidney disease such as HIVAN.

  5. Novel retinoic acid receptor alpha agonists for treatment of kidney disease.

    Science.gov (United States)

    Zhong, Yifei; Wu, Yingwei; Liu, Ruijie; Li, Zhengzhe; Chen, Yibang; Evans, Todd; Chuang, Peter; Das, Bhaskar; He, John Cijiang

    2011-01-01

    Development of pharmacologic agents that protect podocytes from injury is a critical strategy for the treatment of kidney glomerular diseases. Retinoic acid reduces proteinuria and glomerulosclerosis in multiple animal models of kidney diseases. However, clinical studies are limited because of significant side effects of retinoic acid. Animal studies suggest that all trans retinoic acid (ATRA) attenuates proteinuria by protecting podocytes from injury. The physiological actions of ATRA are mediated by binding to all three isoforms of the nuclear retinoic acid receptors (RARs): RARα, RARβ, and RARγ. We have previously shown that ATRA exerts its renal protective effects mainly through the agonism of RARα. Here, we designed and synthesized a novel boron-containing derivative of the RARα-specific agonist Am580. This new derivative, BD4, binds to RARα receptor specifically and is predicted to have less toxicity based on its structure. We confirmed experimentally that BD4 binds to RARα with a higher affinity and exhibits less cellular toxicity than Am580 and ATRA. BD4 induces the expression of podocyte differentiation markers (synaptopodin, nephrin, and WT-1) in cultured podocytes. Finally, we confirmed that BD4 reduces proteinuria and improves kidney injury in HIV-1 transgenic mice, a model for HIV-associated nephropathy (HIVAN). Mice treated with BD4 did not develop any obvious toxicity or side effect. Our data suggest that BD4 is a novel RARα agonist, which could be used as a potential therapy for patients with kidney disease such as HIVAN.

  6. Fatty acids attached to all-trans-astaxanthin alter its cis-trans equilibrium, and consequently its stability, upon light-accelerated autoxidation.

    Science.gov (United States)

    de Bruijn, Wouter J C; Weesepoel, Yannick; Vincken, Jean-Paul; Gruppen, Harry

    2016-03-01

    Fatty acid esterification, common in naturally occurring astaxanthin, has been suggested to influence both colour stability and degradation of all-trans-astaxanthin. Therefore, astaxanthin stability was studied as influenced by monoesterification and diesterification with palmitate. Increased esterification decelerated degradation of all-trans-astaxanthin (RP-UHPLC-PDA), whereas, it had no influence on colour loss over time (spectrophotometry). This difference might be explained by the observation that palmitate esterification influenced the cis-trans equilibrium. Free astaxanthin produced larger amounts of 9-cis isomer whereas monopalmitate esterification resulted in increased 13-cis isomerization. The molar ratios of 9-cis:13-cis after 60min were 1:1.7 (free), 1:4.8 (monopalmitate) and 1:2.6 (dipalmitate). The formation of 9-cis astaxanthin, with its higher molar extinction coefficient than that of all-trans-astaxanthin, might compensate for colour loss induced by conjugated double bond cleavage. As such, it was concluded that spectrophotometry is not an accurate measure of the degradation of the all-trans-astaxanthin molecule.

  7. Transcriptome profiling and genome-wide DNA binding define the differential role of fenretinide and all-trans RA in regulating the death and survival of human hepatocellular carcinoma Huh7 cells.

    Science.gov (United States)

    Hu, Ying; Liu, Hui-Xin; He, Yuqi; Fang, Yaping; Fang, Jianwen; Wan, Yu-Jui Yvonne

    2013-04-01

    Fenretinide is significantly more effective in inducing apoptosis in cancer cells than all-trans retinoic acid (ATRA). The current study uses a genome-wide approach to understand the differential role fenretinide and ATRA have in inducing apoptosis in Huh7 cells. Fenretinide and ATRA-induced gene expressions and DNA bindings were profiled using microarray and chromatin immunoprecipitation with anti-RXRα antibody. The data showed that fenretinide was not a strong transcription regulator. Fenretinide only changed the expressions of 1 093 genes, approximately three times less than the number of genes regulated by ATRA (2 811). Biological function annotation demonstrated that both fenretinide and ATRA participated in pathways that determine cell fate and metabolic processes. However, fenretinide specifically induced Fas/TNFα-mediated apoptosis by increasing the expression of pro-apoptotic genes i.e., DEDD2, CASP8, CASP4, and HSPA1A/B; whereas, ATRA induced the expression of BIRC3 and TNFAIP3, which inhibit apoptosis by interacting with TRAF2. In addition, fenretinide inhibited the expression of the genes involved in RAS/RAF/ERK-mediated survival pathway. In contrast, ATRA increased the expression of SOSC2, BRAF, MEK, and ERK genes. Most genes regulated by fenretinide and ATRA were bound by RXRα, suggesting a direct effect. This study revealed that by regulating fewer genes, the effects of fenretinide become more specific and thus has fewer side effects than ATRA. The data also suggested that fenretinide induces apoptosis via death receptor effector and by inhibiting the RAS/RAF/ERK pathway. It provides insight on how retinoid efficacy can be improved and how side effects in cancer therapy can be reduced.

  8. HEMOPOIETIC SYSTEM

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    2006261 Enhancement of all - trans retinoic acid -induced differentiation by bufalin in primary culture of acute promyelocytic leukmia cells. ZHOU Zhitu (周志图),et al. Dept Med Oncol, 1st Affili Hosp, China Med Univ, Shenyang 110001. Chin J Intern Med 2006; 45(4):314-317. Objective:To investigate the effect of bufalin combined with all -trans retinoic acid induced (ATRA) differentiation of acute promyelocytic leukemia ( API) cells

  9. Promise of Retinoic Acid-Triazolyl Derivatives in Promoting Differentiation of Neuroblastoma Cells.

    Science.gov (United States)

    Lone, Ali Mohd; Dar, Nawab John; Hamid, Abid; Shah, Wajaht Amin; Ahmad, Muzamil; Bhat, Bilal A

    2016-01-20

    Retinoic acid induces differentiation in various types of cells including skeletal myoblasts and neuroblasts and maintains differentiation of epithelial cells. The present study demonstrates synthesis and screening of a library of retinoic acid-triazolyl derivatives for their differentiation potential on neuroblastoma cells. Click chemistry approach using copper(I)-catalyzed azide-alkyne cycloaddition was adopted for the preparation of these derivatives. The neurite outgrowth promoting potential of retinoic acid-triazolyl derivatives was studied on neuroblastoma cells. Morphological examination revealed that compounds 8a, 8e, 8f, and 8k, among the various derivatives screened, exhibited promising neurite-outgrowth inducing activity at a concentration of 10 μM compared to undifferentiated and retinoic acid treated cells. Further on, to confirm this differentiation potential of these compounds, neuroblastoma cells were probed for expression of neuronal markers such as NF-H and NeuN. The results revealed a marked increase in the NF-H and NeuN protein expression when treated with 8a, 8e, 8f, and 8k compared to undifferentiated and retinoic acid treated cells. Thus, these compounds could act as potential leads in inducing neuronal differentiation for future studies.

  10. Excited State s-cis Rotamers Produced by Extreme Red Edge Excitation of all-trans-1,4-Diphenyl-1,3-butadiene

    DEFF Research Database (Denmark)

    Wallace-Williams, Stacie E.; Møller, Søren; Goldbeck, Robert A.;

    1993-01-01

    The shapes of the fluorescence emission and lowest excited singlet-state absorption spectra of all-trans-1,4- diphenylbutadiene (DPB) in hydrocarbon solvents vary with excitation wavelength when exciting on the extreme red edge of the ground-state absorption spectrum. This contrasts with the wave......The shapes of the fluorescence emission and lowest excited singlet-state absorption spectra of all-trans-1,4- diphenylbutadiene (DPB) in hydrocarbon solvents vary with excitation wavelength when exciting on the extreme red edge of the ground-state absorption spectrum. This contrasts...... changes in DPB can be explained in terms of an excitation wavelength-dependent production of s-cis and s-trans rotamer populations in the excited state. The DPB fluorescence emission spectrum was resolved into s-cis and s-trans components. The vibronic structure of the s-cis fluorescence spectrum...

  11. Direct protein-protein interactions and substrate channeling between cellular retinoic acid binding proteins and CYP26B1.

    Science.gov (United States)

    Nelson, Cara H; Peng, Chi-Chi; Lutz, Justin D; Yeung, Catherine K; Zelter, Alex; Isoherranen, Nina

    2016-08-01

    Cellular retinoic acid binding proteins (CRABPs) bind all-trans-retinoic acid (atRA) tightly. This study aimed to determine whether atRA is channeled directly to cytochrome P450 (CYP) CYP26B1 by CRABPs, and whether CRABPs interact directly with CYP26B1. atRA bound to CRABPs (holo-CRABP) was efficiently metabolized by CYP26B1. Isotope dilution experiments showed that delivery of atRA to CYP26B1 in solution was similar with or without CRABP. Holo-CRABPs had higher affinity for CYP26B1 than free atRA, but both apo-CRABPs inhibited the formation of 4-OH-RA by CYP26B1. Similar protein-protein interactions between soluble binding proteins and CYPs may be important for other lipophilic CYP substrates.

  12. The Retinoic Acid Receptor-α mediates human T-cell activation and Th2 cytokine and chemokine production

    Directory of Open Access Journals (Sweden)

    Key Michael

    2008-04-01

    Full Text Available Abstract Background We have recently demonstrated that all-trans-retinoic acid (ATRA and 9-cis-retinoic acid (9-cis RA promote IL-4, IL-5 and IL-13 synthesis, while decreasing IFN-γ and TNF-α expression by activated human T cells and reduces the synthesis of IL-12p70 from accessory cells. Here, we have demonstrated that the observed effects using ATRA and 9-cis RA are shared with the clinically useful RAR ligand, 13-cis retinoic acid (13-cis RA, and the retinoic acid receptor-α (RAR-α-selective agonist, AM580 but not with the RAR-β/γ ligand, 4-hydroxyphenylretinamide (4-HPR. Results The increase in type 2 cytokine production by these retinoids correlated with the expression of the T cell activation markers, CD69 and CD38. The RAR-α-selective agonist, AM580 recapitulated all of the T cell activation and type 2 cytokine-inducing effects of ATRA and 9-cis-RA, while the RAR-α-selective antagonist, RO 41–5253, inhibited these effects. Conclusion These results strongly support a role for RAR-α engagement in the regulation of genes and proteins involved with human T cell activation and type 2 cytokine production.

  13. Effects of synthetic retinoids and retinoic acid isomers on the expression of alkaline phosphatase in F9 teratocarcinoma cells.

    Science.gov (United States)

    Gianni, M; Zanotta, S; Terao, M; Garattini, S; Garattini, E

    1993-10-15

    Expression of ALP in F9 teratocarcinoma cells is induced by all-trans retinoic acid (ATRA) (Gianni' et al., Biochem. J. 274: 673-678, 1991). The specific ligand for retinoic acid related receptors (RXRs), 9-cis retinoic acid (9-cis RA), and three synthetic analogs binding to the alpha, beta and gamma forms of the retinoic acid receptors (RARs), AM580, CD2019, and CD437, were used to study their effects on alkaline phosphatase (ALP) enzymatic activity and mRNA levels. At concentrations close to the Kd for their respective receptors, 9-cis RA, AM580 (the RAR alpha agonist) and CD437 (the RAR gamma agonist) clearly upregulate the expression of the ALP gene, whereas the effect of CD2019 (the RAR beta agonist) is very modest. A specific inhibitor of the RAR alpha, Ro 41-5253, completely blocks the induction of ALP triggered by AM580, while it has minor effects on the upregulation caused by ATRA, 9-cis RA, CD437 and CD2019. The induction of ALP observed with the various retinoids is inhibited by the contemporaneous treatment with dibutyryl cAMP. The levels of the RAR alpha and gamma transcripts are unaltered, while RAR beta mRNAs are induced by ATRA, AM580, CD437 and to a lower extent by 9-cis RA and CD2019.

  14. Altered retinoic acid metabolism in diabetic mouse kidney identified by O isotopic labeling and 2D mass spectrometry.

    Directory of Open Access Journals (Sweden)

    Jonathan M Starkey

    Full Text Available Numerous metabolic pathways have been implicated in diabetes-induced renal injury, yet few studies have utilized unbiased systems biology approaches for mapping the interconnectivity of diabetes-dysregulated proteins that are involved. We utilized a global, quantitative, differential proteomic approach to identify a novel retinoic acid hub in renal cortical protein networks dysregulated by type 2 diabetes.Total proteins were extracted from renal cortex of control and db/db mice at 20 weeks of age (after 12 weeks of hyperglycemia in the diabetic mice. Following trypsinization, (18O- and (16O-labeled control and diabetic peptides, respectively, were pooled and separated by two dimensional liquid chromatography (strong cation exchange creating 60 fractions further separated by nano-HPLC, followed by peptide identification and quantification using mass spectrometry. Proteomic analysis identified 53 proteins with fold change >or=1.5 and pretinoic acid as a key signaling hub that was altered in the diabetic renal cortical proteome. Western blotting and real-time PCR confirmed diabetes-induced upregulation of RALDH1, which was localized by immunofluorescence predominantly to the proximal tubule in the diabetic renal cortex, while PCR confirmed the downregulation of ADH identified with mass spectrometry. Despite increased renal cortical tissue levels of retinol and RALDH1 in db/db versus control mice, all-trans-retinoic acid was significantly decreased in association with a significant decrease in PPARbeta/delta mRNA.Our results indicate that retinoic acid metabolism is significantly dysregulated in diabetic kidneys, and suggest that a shift in all-trans-retinoic acid metabolism is a novel feature in type 2 diabetic renal disease. Our

  15. Within brown-fat cells, UCP1-mediated fatty acid-induced uncoupling is independent of fatty acid metabolism.

    Science.gov (United States)

    Shabalina, Irina G; Backlund, Emma C; Bar-Tana, Jacob; Cannon, Barbara; Nedergaard, Jan

    2008-01-01

    In the present investigation, we have utilized the availability of UCP1(-/-) mice to examine a wide range of previously proposed lipid activators of Uncoupling Protein 1 (UCP1) in its native environment, i.e. in the brown-fat cells. A non-metabolizable fatty acid analogue, beta,beta cent-methyl-substituted hexadecane alpha,omega-dicarboxylic acid (Medica-16) is a potent UCP1 (re)activator in brown-fat cells, despite its bipolar structure. All-trans-retinoic acid activates UCP1 within cells, whereas beta-carotene only does so after metabolism. The UCP1-dependent effects of fatty acids are positively correlated with their chain length. Medium-chain fatty acids are potent UCP1 activators in cells, despite their lack of protonophoric properties in mitochondrial membranes. Thus, neither the ability to be metabolized nor an innate uncoupling/protonophoric ability is a necessary property of UCP1 activators within brown-fat cells.

  16. Effects of various factors of ultrasonic treatment on the extraction yield of all-trans-lycopene from red grapefruit (Citrus paradise Macf.).

    Science.gov (United States)

    Xu, Yuan; Pan, Siyi

    2013-07-01

    The effects of various factors, including the extraction time, temperature, solvent/material ratio, the ultrasonic intensity and duty cycle of ultrasonic irradiation on the extraction yield of all-trans-lycopene from red grapefruit by ultrasound-assisted extraction (UAE) were investigated. In comparison with conventional solvent extraction (CSE), UAE showed a pronounced greater extraction yield and reduced extraction time effectively with a peak value at 30 min. The extraction yield was significantly influenced by temperature and the optimum condition was 30 °C. The extraction yield increased with increasing of solvent/material ratio until equilibrium was arrived at the optimal ratio of 3:1 (mL/g). The extraction yield increased first and then decreased with an increase in ultrasonic intensity. The extraction yield of UAE increased with the increase of duty cycle, whereas pulsed ultrasound with proper intervals was more efficient than continuous ultrasonication. The degradation via isomerisation of all-trans-lycopene under ultrasonic treatment was also observed with the formation of 9,13'-di-cis-, 9,13-di-cis-, 15-cis-, 13-cis- and 9-cis-lycopene isomers which were tentatively identified by HPLC-PAD.

  17. Myeloid differentiation and retinoblastoma phosphorylation changes in HL-60 cells induced by retinoic acid receptor- and retinoid X receptor-selective retinoic acid analogs.

    Science.gov (United States)

    Brooks, S C; Kazmer, S; Levin, A A; Yen, A

    1996-01-01

    The ability of subtypes of retinoic acid receptors (RARs) and retinoid X receptors (RXRs) singly and in combination to elicit myeloid differentiation, G1/0-specific growth arrest, and retinoblastoma (RB) tumor suppressor protein dephosphorylation was determined in the human myeloblastic leukemia cell line HL-60 using subtype-selective retinoic acid (RA) analogs. RA analogs that selectively bind only to RARs (Am580 and/or TTNPB) or to RXRs (Ro 25-6603, SR11237, and/or SR11234) did not elicit the above-mentioned three cellular responses. In contrast, simultaneous treatment with both an RAR-selective ligand (Am580 or TTNPB) and an RXR-selective ligand (Ro 25-6603, SR11237, or SR11234) induced all three cellular processes. An RAR alpha-selective ligand used with an RXR-selective ligand generated the same responses as did all-trans RA or 9-cis RA, which affect both families of receptors, suggesting an important role for RAR alpha among RAR subtypes in eliciting cellular response. Consistent with this finding, the RAR alpha antagonist, Ro 41-5253, reduced the level of the cellular responses elicited by treatment with an RAR alpha-selective ligand plus RXR-selective ligand. The coupling of the shift of RB to its hypophosphorylated form with G1/0 arrest and differentiation in response to ligands is consistent with a possible role of RB as a downstream target or effector of RAR alpha and RXR in combination.

  18. Induction of cranial and posterior trunk neural crest by exogenous retinoic acid in zebrafish

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Retinoic acid (RA) plays an important role in development of vertebrate embryos. We demonstrate impacts of exogenous RA on the formation of neural crest cells in zebrafish using specific neural crest markers sox9b and crestin. Treatment with all-trans RA at 10?7 mmol/L at 50% epiboly induces sox9b expression in the forebrain and crestin expression in the forebrain and midbrain, resulting in significant increase of pigment cells in the head derived from the cranial neural crest. In addition, RA treatment induces expression of sox9b and crestin in the caudal marginal cells of the neuroectoderm during early segmentation. Earlier commitment of these cells to the neural crest fate in the posterior margins leads to abnormal development of the posterior body, probably by preventing mingling of ventral derived and dorsal-derived cells during the formation of the tailbud.

  19. The histone demethylase PHF8 governs retinoic acid response in acute promyelocytic leukemia.

    Science.gov (United States)

    Arteaga, Maria Francisca; Mikesch, Jan-Henrik; Qiu, Jihui; Christensen, Jesper; Helin, Kristian; Kogan, Scott C; Dong, Shuo; So, Chi Wai Eric

    2013-03-18

    While all-trans retinoic acid (ATRA) treatment in acute promyelocytic leukemia (APL) has been the paradigm of targeted therapy for oncogenic transcription factors, the underlying mechanisms remain largely unknown, and a significant number of patients still relapse and become ATRA resistant. We identified the histone demethylase PHF8 as a coactivator that is specifically recruited by RARα fusions to activate expression of their downstream targets upon ATRA treatment. Forced expression of PHF8 resensitizes ATRA-resistant APL cells, whereas its downregulation confers resistance. ATRA sensitivity depends on the enzymatic activity and phosphorylation status of PHF8, which can be pharmacologically manipulated to resurrect ATRA sensitivity to resistant cells. These findings provide important molecular insights into ATRA response and a promising avenue for overcoming ATRA resistance.

  20. Topical retinoic acid changes the epidermal cell surface glycosylation pattern towards that of a mucosal epithelium

    DEFF Research Database (Denmark)

    Griffiths, C E; Dabelsteen, Erik; Voorhees, J J

    1996-01-01

    for carbohydrate synthesis, are influenced by retinoids. Thus, we investigated whether epidermal cell surface glycosylation is altered in skin treated with topical RA, and contrasted it with changes induced by topical SLS. Skin biopsies were obtained from seven normal volunteers who had been treated, on three......-treated epidermis was not significantly different from that observed after vehicle treatment. Thus, RA treatment converts normal stratified epithelium towards the phenotype of mucosal epithelium with a decrease in T antigen and a concomitant increase in Ley. These changes are not observed following treatment......Topical all-trans retinoic acid (RA) produces a number of epidermal changes which are indistinguishable from those observed following treatment with a local irritant, namely sodium lauryl sulphate (SLS). This observation has led to criticism that the efficacy of RA in disorders such as photoageing...

  1. Anti-inflammatory and anti-hyperalgesic effect of all-trans retinoic acid in carrageenan-induced paw edema in Wistar rats: Involvement of peroxisome proliferator-activated receptor-β/δ receptors

    Directory of Open Access Journals (Sweden)

    Navneet Gill

    2013-01-01

    Conclusion: From above findings, it can be concluded that ATRA exerts anti-inflammatory and anti-hyperalgesic effect, possibly through activation of PPAR-β/δ and subsequent reduction of oxido-nitrosative stress.

  2. Vitamin A increases nerve growth factor and retinoic acid receptor beta and improves diabetic neuropathy in rats.

    Science.gov (United States)

    Hernández-Pedro, Norma; Granados-Soto, Vinicio; Ordoñez, Graciela; Pineda, Benjamin; Rangel-López, Edgar; Salazar-Ramiro, Aleli; Arrieta, Oscar; Sotelo, Julio

    2014-09-01

    All-trans retinoic acid (ATRA) promotes the endogenous expression of both nerve growth factor (NGF) and retinoic acid receptor beta (RAR-β). We have previously shown that the administration of ATRA partly reverts the damage induced by diabetic neuropathy (DN). In this investigation, we evaluated the effects of vitamin A, a commercial, inexpensive compound of retinoic acid, on the therapy of DN. A total of 70 rats were randomized into 4 groups. Group A was the control, and groups B, C, and D received a total dose of 60 mg/kg streptozotocin intraperitoneally. When signs of DN developed, groups C and D were treated either with vitamin A (20,000 IU) or with ATRA 25 mg/kg for 60 days. Plasma glucose, contents of NGF, thermal and nociceptive tests, and RAR-β expression were evaluated. All diabetic rats developed neuropathy. The treatment with vitamin A and ATRA reverted similarly the sensorial disturbances, which was associated with increased contents of NGF and RAR-β expression. Our results indicate that the administration of vitamin A has the same therapeutic effect as ATRA on peripheral neuropathy and suggest its potential therapeutic use in patients with diabetes.

  3. Effect of Retinoic acid on Platelet-derived Growth Factor and Lung Development in Newborn Rats

    Institute of Scientific and Technical Information of China (English)

    陈红兵; 常立文; 刘汉楚; 容志惠; 祝华平; 张谦慎; 李文斌

    2004-01-01

    Summary: The influence of platelet-derived growth factor (PDGF) on lung development in newborn rats and the effect of retinoic acid (RA) on PDGF in lung development were investigated. Newborn Sprague-Dawley (SD) rats were randomly assigned to two groups: control group and RA group.The rats in RA group was intraperitoneally injected with all trans-retinoic acid (500 μg/kg every day) for consecutive 3 days after birth, while those in the control group were not subjected to intervention, Immunohistochemical assay was performed to locate the expression of PDGF. mRNA levels of PDGF were measured by reverse transcription polymerase chain reaction (RT-PCR) at age of 1, 3, 5, 7, 10, 14, 21 days. The method of radial alveolar counts (RAC) was used to measure the amount of the alveoli of the lungs. It was found that with increasing days, levels of PDGF-A and PDGF-B changed to verying degrees. RA could elevate significantly the expression levels of PDGF A mRNA and protein (P<0.01), but not affect the expression levels of PDGF-B mRNA and pro tein markedly (P>0.05). It is suggested that PDGF might play an important role in lung development. RA can stimulate lung development through increasing the expression levels of PDGF-A mRNA and protein.

  4. Experimental effect of retinoic acids on apoptosis during the development of diabetic retinopathy

    Directory of Open Access Journals (Sweden)

    Nami Nishikiori

    2008-03-01

    Full Text Available Nami Nishikiori1,2, Makoto Osanai2, Hideki Chiba2, Takashi Kojima2, Shuichiro Inatomi1,2, Hiroshi Ohguro1, Norimasa Sawada2Departments of 1Ophthalmology and 2Pathology, Sapporo Medical University School of MedicinePurpose: This study was conducted to investigate whether retinoic acids (RAs had any effect on apoptosis during the development of diabetic retinopathy.Methods: To investigate whether RAs had any effect on apoptosis during the development of diabetic retinopathy, we housed 32 C57BL/6 male mice and induced diabetes in 24 by intra peritoneal injections of streptozotocin (STZ; Sigma, St Louis, MO and treated 16 of the diabetic mice with the RAs, all-trans-retinoic acid (ATRA (seven mice and 4-[(5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-naphthalenylcarboxamido] benzoic acid (Am580 (nine mice. The other eight mice were used as diabetic controls. We then measured apoptosis in the retina by TdT-dUTP terminal nick-end labeling assay.Results: RAs inhibited the apoptosis of retinal cells in diabetic retinopathy. Many apoptotic cells were observed in retinas of the eight diabetic control mice (mean value and SD: 37.8 ± 6.9, whereas when diabetic mice were treated with RAs, the number of apoptotic cells significantly decreased (mean value and SD: 9.9 ± 6.4 for the seven ATRA-treated diabetic mice and 9.8 ± 5.9 for the nine Am580-treated diabetic mice (p < 0.05.Conclusion: Treatment with RAs decreases apoptosis during the development of diabetic retinopathy.Keywords: retinoic acids, apoptosis, diabetic retinopathy, glial cell line-derived neurotrophic factor

  5. Evidence of increased reactive species formation by retinol, but not retinoic acid, in PC12 cells.

    Science.gov (United States)

    Gelain, Daniel Pens; Moreira, José Claudio Fonseca

    2008-04-01

    The biological effects of vitamin A (retinol) are generally ascribed to the activation of nuclear retinoid receptors by retinoic acid (RA), considered the most biologically active retinoid. However, it is not established whether the cytotoxic effects of vitamin A are due to retinoid receptors activation by RA. Vitamin A-related toxicity is associated with cellular redox modifications, often leading to severe oxidative damage, but the role of RA in this effect is also uncertain. We therefore studied the formation of intracellular reactive species induced by retinol and retinoic acid in PC12 cells, using an in vitro dichlorofluorescein (DCFH) fluorescence real-time assay. We observed that retinol, but not retinoic acid, induced a steady increase in DCF-based fluorescence over 60 min of incubation, and this increase was reversed by antioxidant (N-acetyl-cysteine and alpha-tocopherol) pre-treatment. This effect was also inhibited by the iron chelator 1,10-phenantroline and the impermeable calcium chelator EGTA. These results suggest that vitamin A-associated cytotoxicity is probably related to an oxidant mechanism dependent on iron and calcium, and the formation of intracellular reactive species is related to retinol, but not to RA.

  6. A femtosecond transient absorption spectroscopic study on a carbonyl-containing carotenoid analogue, 2-(all-trans-retinylidene)-indan-1,3-dione

    Science.gov (United States)

    Kusumoto, Toshiyuki; Kosumi, Daisuke; Uragami, Chiasa; Frank, Harry A.; Birge, Robert R.; Cogdell, Richard J.; Hashimoto, Hideki

    2011-01-01

    The photophysical properties of a carbonyl-containing carotenoid analogue in an s-cis configuration, relative to the conjugated π system, 2-(all-trans-retinylidene)-indan-1,3-dione (C20Ind), were investigated by femtosecond time-resolved spectroscopy in various solvents. The lifetime of the optically forbidden S1 state of C20Ind becomes long as solvent polarity increases. This trend is completely opposite to the situation of S1-ICT dynamics of carbonyl-containing carotenoids, such as peridinin and fucoxanthin. Excitation energy dependence of the transient absorption measurements shows that the transient absorption spectra in non-polar solvents were originated from two distinct transient species, while those in polar and protic solvents are due to a single transient species. By referring to the results of MNDO-PSDCI (modified neglect of differential overlap with partial single- and double-configuration interaction) calculations, we conclude: (1) In polar and protic solvents, the S1 state is generated following excitation up to the S2 state; (2) In non-polar solvents, however, both the S1 and 1nπ* states are generated; and (3) C20Ind does not generate the S1-ICT state, despite the fact that it has two conjugated carbonyl groups. PMID:21361262

  7. Inhibition of mitotic kinase Aurora suppresses Akt-1 activation and induces apoptotic cell death in all-trans retinoid acid-resistant acute promyelocytic leukemia cells

    Directory of Open Access Journals (Sweden)

    Long Zi-Jie

    2011-05-01

    Full Text Available Abstract Background Aurora kinase ensures accurate chromosome segregation during cell cycle, maintaining genetic integrity in cell division. VX-680, a small-molecule Aurora kinase inhibitor, interferes with mitotic entry and formation of bipolar spindles. Here, we evaluated VX-680 as a potential agent for treatment of all-trans retinoid acid (ATRA-resistant acute promyelocytic leukemia (APL in vitro. Methods CD11b expression was utilized to assess cell differentiation by flow cytometry. Immunofluorescence staining was conducted to analyze formation of cell monopolar spindle. Cell proliferation was evaluated by MTT assay. Sub-G1 population and Annexin V/PI staining were used to measure cell apoptosis. Hoechst 33342 staining was applied for identifying morphological changes in nucleus of apoptotic cell. Aurora-A (Aur-A activation and the signaling pathways involved in apoptosis were detected by Western blot. JC-1 probe was employed to measure mitochondrial depolarization. Results VX-680 inhibited Aur-A by reducing autophosphorylation at the activation site, Thr288, accompanied by producing monopolar mitotic spindles in APL cell line NB4-R2 that was resistant to ATRA. In addition, we found that VX-680 inhibited cell proliferation as assessed by MTT assay. Flow cytometry showed that VX-680 led to apoptotic cell death in both dose- and time-dependent manners by either Sub-G1 or Annexin V/PI analysis. Hoechst 33342 staining represented typical apoptotic cells with nuclear fragmentation in VX-680 treated cells. Importantly, VX-680 inhibition of Aurora kinase suppressed Akt-1 activation and induced mitochondrial depolarization, which eventually resulted in apoptosis by activation of caspase pathway, as indicated by increasing proteolytic cleavage of procaspase-3 and poly ADP ribose polymerase (PARP in NB4-R2 cells. Conclusions Our study suggested potential clinical use of mitotic Aurora kinase inhibitor in targeting ATRA-resistant leukemic cells.

  8. Triphenyl phosphate-induced developmental toxicity in zebrafish: Potential role of the retinoic acid receptor

    Energy Technology Data Exchange (ETDEWEB)

    Isales, Gregory M.; Hipszer, Rachel A.; Raftery, Tara D. [Department of Environmental Health Sciences, Arnold School of Public Health, University of South Carolina, Columbia, SC (United States); Chen, Albert; Stapleton, Heather M. [Division of Environmental Sciences and Policy, Nicholas School of the Environment, Duke University, Durham, NC (United States); Volz, David C., E-mail: volz@mailbox.sc.edu [Department of Environmental Health Sciences, Arnold School of Public Health, University of South Carolina, Columbia, SC (United States)

    2015-04-15

    Highlights: • Triphenyl phosphate-induced toxicity in zebrafish embryos is enhanced in the presence of a retinoic acid receptor antagonist. • Triphenyl phosphate uptake or metabolism within zebrafish embryos is not altered in the presence of a retinoic acid receptor antagonist. • Triphenyl phosphate decreases expression of cytochrome P450 26a1 in zebrafish embryos. • Triphenyl phosphate inhibits retinoic acid-induced activation of human retinoic acid receptors. - Abstract: Using zebrafish as a model, we previously reported that developmental exposure to triphenyl phosphate (TPP) – a high-production volume organophosphate-based flame retardant – results in dioxin-like cardiac looping impairments that are independent of the aryl hydrocarbon receptor. Using a pharmacologic approach, the objective of this study was to investigate the potential role of retinoic acid receptor (RAR) – a nuclear receptor that regulates vertebrate heart morphogenesis – in mediating TPP-induced developmental toxicity in zebrafish. We first revealed that static exposure of zebrafish from 5–72 h post-fertilization (hpf) to TPP in the presence of non-toxic concentrations of an RAR antagonist (BMS493) significantly enhanced TPP-induced toxicity (relative to TPP alone), even though identical non-toxic BMS493 concentrations mitigated retinoic acid (RA)-induced toxicity. BMS493-mediated enhancement of TPP toxicity was not a result of differential TPP uptake or metabolism, as internal embryonic doses of TPP and diphenyl phosphate (DPP) – a primary TPP metabolite – were not different in the presence or absence of BMS493. Using real-time PCR, we then quantified the relative change in expression of cytochrome P450 26a1 (cyp26a1) – a major target gene for RA-induced RAR activation in zebrafish – and found that RA and TPP exposure resulted in a ∼5-fold increase and decrease in cyp26a1 expression, respectively, relative to vehicle-exposed embryos. To address whether TPP may

  9. Mefenamic Acid Induced Nephrotoxicity: An Animal Model

    Directory of Open Access Journals (Sweden)

    Muhammad Nazrul Somchit

    2014-12-01

    Full Text Available Purpose: Nonsteroidal anti-inflammatory drugs (NSAIDs are used for the treatment of many joint disorders, inflammation and to control pain. Numerous reports have indicated that NSAIDs are capable of producing nephrotoxicity in human. Therefore, the objective of this study was to evaluate mefenamic acid, a NSAID nephrotoxicity in an animal model. Methods: Mice were dosed intraperitoneally with mefenamic acid either as a single dose (100 or 200 mg/kg in 10% Dimethyl sulfoxide/Palm oil or as single daily doses for 14 days (50 or 100 mg/kg in 10% Dimethyl sulfoxide/Palm oil per day. Venous blood samples from mice during the dosing period were taken prior to and 14 days post-dosing from cardiac puncture into heparinized vials. Plasma blood urea nitrogen (BUN and creatinine activities were measured. Results: Single dose of mefenamic acid induced mild alteration of kidney histology mainly mild glomerular necrosis and tubular atrophy. Interestingly, chronic doses induced a dose dependent glomerular necrosis, massive degeneration, inflammation and tubular atrophy. Plasma blood urea nitrogen was statistically elevated in mice treated with mefenamic acid for 14 days similar to plasma creatinine. Conclusion: Results from this study suggest that mefenamic acid as with other NSAIDs capable of producing nephrotoxicity. Therefore, the study of the exact mechanism of mefenamic acid induced severe nephrotoxicity can be done in this animal model.

  10. Clinical Study on Prospective Efficacy of All-Trans Acid, Realgar-Indigo Naturalis Formula Combined with Chemotherapy as Maintenance Treatment of Acute Promyelocytic Leukemia

    Directory of Open Access Journals (Sweden)

    Li Xiang-Xin

    2014-01-01

    Full Text Available Objectives. To test the efficiency and safety of sequential application of retinoic acid (ATRA, Realgar-Indigo naturalis formula (RIF and chemotherapy (CT were used as the maintenance treatment in patients with acute promyelocytic leukemia (APL. Methods. This was a retrospective study of 98 patients with newly diagnosed APL who accepted two different maintenance treatments. After remission induction and consolidation chemotherapy according to their Sanz scores, patients received two different kinds of maintenance scheme. The first regimen was using ATRA, RIF, and standard dose of CT sequentially (ATRA/RIF/CT regimen, while the second one was using ATRA and low dose of chemotherapy with methotrexate (MTX plus 6-mercaptopurine (6-MP alternately (ATRA/CTlow regimen. The OS, DFS, relapse rate, minimal residual disease, and adverse reactions in two groups were monitored and evaluated. Results. ATRA/RIF/CT regimen could effectively reduce the chance of relapse in different risk stratification of patients, but there was no significant difference in 5-year DFS rate and OS rate between the two groups. Besides, the patients in the experimental group suffered less severe adverse reactions than those in the control group. Conclusions. The repeated sequential therapeutic regimen to APL with ATRA, RIF, and chemotherapy is worth popularizing for its high effectiveness and low toxicity.

  11. Retinoic acid signalling is activated in the postischemic heart and may influence remodelling.

    Directory of Open Access Journals (Sweden)

    Dusan Bilbija

    Full Text Available BACKGROUND: All-trans retinoic acid (atRA, an active derivative of vitamin A, regulates cell differentiation, proliferation and cardiac morphogenesis via transcriptional activation of retinoic acid receptors (RARs acting on retinoic acid response elements (RARE. We hypothesized that the retinoic acid (RA signalling pathway is activated in myocardial ischemia and postischemic remodelling. METHODS AND FINDINGS: Myocardial infarction was induced through ligating the left coronary artery in mice. In vivo cardiac activation of the RARs was measured by imaging RARE-luciferase reporter mice, and analysing expression of RAR target genes and proteins by real time RT-PCR and western blot. Endogenous retinoids in postinfarcted hearts were analysed by triple-stage liquid chromatography/tandem mass spectrometry. Cardiomyocytes (CM and cardiofibroblasts (CF were isolated from infarcted and sham operated RARE luciferase reporter hearts and monitored for RAR activity and expression of target genes. The effect of atRA on CF proliferation was evaluated by EdU incorporation. Myocardial infarction increased thoracic RAR activity in vivo (p<0.001, which was ascribed to the heart through ex vivo imaging (p = 0.002 with the largest signal 1 week postinfarct. This was accompanied by increased cardiac gene and protein expression of the RAR target genes retinol binding protein 1 (p = 0.01 for RNA, p = 0,006 for protein and aldehyde dehydrogenase 1A2 (p = 0.04 for RNA, p = 0,014 for protein, while gene expression of cytochrome P450 26B1 was downregulated (p = 0.007. Concomitantly, retinol accumulated in the infarcted zone (p = 0.02. CM and CF isolated from infarcted hearts had higher luminescence than those from sham operated hearts (p = 0.02 and p = 0.008. AtRA inhibited CF proliferation in vitro (p = 0.02. CONCLUSION: The RA signalling pathway is activated in postischemic hearts and may play a role in regulation of damage and

  12. In vitro study on arsenic sulfide (realgar)-induced apoptosis of retinoic acid susceptible or resistant acute promyelocytic leukemia cell lines

    Institute of Scientific and Technical Information of China (English)

    CHEN Si-yu; LIU Shan-xi; LI Xin-min

    2002-01-01

    Objective: To further understand the possible mechanisms of arsenic sulfide (realgar) in the treatment of acute promyelocytic leukemia (APL). Methods: All-trans retinoic acid (ATRA)-susceptible APL cell line (NB4 cells) and ATRA-resistant APL cell line (MR2 subclone) were used as models in vitro. At various times after incubated with various concentrations of realgar, NB4 and MR2 cells were observed by cell viability, cell proliferation and cell morphology; cell cycle and the expression of Annexin V were assayed by flow cytometry. Results: Cell viability and proliferation of NB4 and MR2 cells were inhibited after the treatment,to some extent, in a dose and time dependent manner. 177-711 μg/L of realgar treated NB4 and MR2 cell presented morphologically some features of apoptotic cells such as intact cell membrane, chromatin condensation and nuclear fragmentation, apoptosis body could be found by electron microscopy as well. Sub-G1 ceils andcell cycle arrest were observed by flow cytometry. The proportion of Annexin V -FITC+/PI cells, which represent apoptotic cells, was up-regulated. Conclusion: Realgar could induce apoptosis of acute promyelocytic leukemia cell despite its susceptibility to retinoic acid in the way that may be different from retinoic acid.

  13. Sequential Analysis for Comparing the Effect of Keyin Decoction(克银方) with Retinoic Acid in Treating Psoriasis

    Institute of Scientific and Technical Information of China (English)

    WANG Yan-ning(王砚宁); GU Jun(顾军)

    2003-01-01

    Objective: To compare the effect of Keyin Decoction(克银方)with retinoic acid in treatingpsoriasis. Methods: One hundred and six patients were randomly divided by paired grouping into the KYD group and the all-trans retinoic acid (RA) group, 53 in each group with 19 cases belonging to Wind-Heat Syndrome type and 34 to Wind-Dryness type. The Wind-Heat Syndrome type in the KYD group was trea- ted with KYD Ⅰ (with the action of rearing Heat, removing Dampness, cooling blood and dispelling Wind), and the Wind-Dryness type with KYD Ⅱ (with the action of nourishing blood, moistening skin and dredging Qi-blood circulation, ). The RA group was treated with RA. Sequential analysis was adopted to observe the effect. At the same time, the adverse reaction was observed. Results: When the test got to the 44th pair of patients, the scription of result reached the UA line of sequential chart, suggesting that the efficacy of KYD was superior to that of RA. Skin lesion subsidence rate in the KYD group and the RA group was 39.6% and 20.8% respectively with significant difference (P<0.05). And for the patients of progressive phase in the two groups, skin lesion subsidence rate was 57.8% and 21.1% respectively (P<0.05). No obvious adverse reaction was found in the KYD group. Conclusion: Keyin Decoction had goodeffect in treating psoriasis.

  14. Growth Inhibition and Apoptosis Induced by Retinoic Acid Combined with Interferon Alpha-2a on Transitional Cell Carcinoma of Bladder

    Institute of Scientific and Technical Information of China (English)

    QIANLi-xin; LIUXun-liang; ZHOUJian-wei; MonicaLiebert; ZOUChang-chun; ZOUChang-ping

    2004-01-01

    To identify new favorable agents and develop novel approaches for the chemoprevention and treatment of superficial bladder cancer and invesligate the effects of combination of relinoids and interferon α-2a on growth inhibition and apoptosis induction in bladder cancer cell lines. Methods: Four bladder cancer cell lines, grade 1 to 3,and two retinoids, all-trans-retinoic acid(ATRA) ,9.cis retinoic acid(9cRA) ,combined with inteferon α-2a(INF),were used in the study.We compared the competence of these agents to inhibit growth, induce apoptosis, affect the exptession of nuclear retinoid receptors, and modulate STAT1 protein. Resu/ts: Most of the bladder cancer cell lines were resistant to the effect of ATRA and 9cRA on growth inhibition and apoptosis induction, even at higher concentration (10-5M).The effects of ATRA and 9c RA on cell growth and apoptosis were enhanced by INF α-2a.Combination of ATRA and IFNa-2a induced ~ and Slat 1 expression in three bladder cancer cell lines, ~: The results demonstrated that INFw2a synergize with the inhibitory effect of ATRA and 9c RA on the growth intn'bition and apoptosis of bladder cancer cells in vitro, which suggested that it has a potenlJal intexest for the trealment of transitimml cell carcinmna of bladder.

  15. Transcriptional regulation of genes involved in retinoic acid metabolism in Senegalese sole larvae.

    Science.gov (United States)

    Boglino, Anaïs; Ponce, Marian; Cousin, Xavier; Gisbert, Enric; Manchado, Manuel

    2017-01-01

    The aim of this study was the characterization of transcriptional regulatory pathways mediated by retinoic acid (RA) in Senegalese sole larvae. For this purpose, pre-metamorphic larvae were treated with a low concentration of DEAB, an inhibitor of RALDH enzyme, until the end of metamorphosis. No differences in growth, eye migration or survival were observed. Nevertheless, gene expression analysis revealed a total of 20 transcripts differentially expressed during larval development and only six related with DEAB treatments directly involved in RA metabolism and actions (rdh10a, aldh1a2, crbp1, igf2r, rarg and cyp26a1) to adapt to a low-RA environment. In a second experiment, post-metamorphic larvae were exposed to the all-trans RA (atRA) observing an opposite regulation for those genes involved in RA synthesis and degradation (rdh10a, aldh1a2, crbp1 and cyp26a1) as well as other related with thyroid- (dio2) and IGF-axes (igfbp1, igf2r and igfbp5) to balance RA levels. In a third experiment, DEAB-pretreated post-metamorphic larvae were exposed to atRA and TTNPB (a specific RAR agonist). Both drugs down-regulated rdh10a and aldh1a2 and up-regulated cyp26a1 expression demonstrating their important role in RA homeostasis. Moreover, five retinoic receptors that mediate RA actions, the thyroid receptor thrb, and five IGF binding proteins changed differentially their expression. Overall, this study demonstrates that exogenous RA modulates the expression of some genes involved in the RA synthesis, degradation and cellular transport through RAR-mediated regulatory pathways establishing a negative feedback regulatory mechanism necessary to balance endogenous RA levels and gradients.

  16. Retinoic acid receptor agonists regulate expression of ATP-binding cassette transporter G1 in macrophages.

    Science.gov (United States)

    Ayaori, Makoto; Yakushiji, Emi; Ogura, Masatsune; Nakaya, Kazuhiro; Hisada, Tetsuya; Uto-Kondo, Harumi; Takiguchi, Shunichi; Terao, Yoshio; Sasaki, Makoto; Komatsu, Tomohiro; Iizuka, Maki; Yogo, Makiko; Uehara, Yoshinari; Kagechika, Hiroyuki; Nakanishi, Tsuyoshi; Ikewaki, Katsunori

    2012-04-01

    ABC transporter G1 (ABCG1) plays a pivotal role in HDL-mediated cholesterol efflux and atherogenesis. We investigated whether, and how, retinoic acid receptors (RARs) regulate ABCG1 expression in macrophages. All-trans retinoic acid (ATRA), an RAR ligand, increased ABCG1 protein levels and apoA-I/HDL-mediated cholesterol efflux from the macrophages. Both ATRA and other RAR agonists, TTNPB and Am580, increased major transcripts driven by promoter B upstream of exon 5, though minor transcripts driven by promoter A upstream of exon 1 were only increased by ATRA. The stimulatory effects of ATRA on ABCG1 expression were completely abolished in the presence of RAR/RXR antagonists but were only partially canceled in the presence of an LXR antagonist. Adenovirus with overexpressed oxysterol sulfotransferase abolished the LXR pathway, as previously reported, and ATRA-responsiveness in ABCA1/ABCG1 expressions were respectively attenuated by 38 and 22% compared to the control virus. Promoter assays revealed that ABCG1 levels were regulated more by promoter B than promoter A, and ATRA activated promoter B in a liver X receptor-responsive element (LXRE)-dependent manner. Further, LXRE-B in intron 7, but not LXRE-A in intron 5, enhanced ATRA responsiveness under overexpression of all RAR isoforms-RARα/β/γ. In contrast, the activation of promoter B by TTNPB depended on LXRE-B and RARα, but not on RARβ/γ. Finally, chromatin immunoprecipitation and gel-shift assays revealed a specific and direct repeat 4-dependent binding of RARα to LXRE-B. In conclusion, RAR ligands increase ABCA1/G1 expression and apoA-I/HDL-mediated cholesterol efflux from macrophages, and modulate ABCG1 promoter activity via LXRE-dependent mechanisms.

  17. Bile Acid-Induced Suicidal Erythrocyte Death

    Directory of Open Access Journals (Sweden)

    Elisabeth Lang

    2016-04-01

    Full Text Available Background/Aims: In nucleated cells, bile acids may activate cation channels subsequently leading to entry of Ca2+. In erythrocytes, increase of cytosolic Ca2+ activity triggers eryptosis, the suicidal death of erythrocytes characterized by phosphatidylserine exposure at the cell surface and cell shrinkage. Eryptosis is triggered by bile duct ligation, an effect partially attributed to conjugated bilirubin. The present study explored, whether bile acids may stimulate eryptosis. Methods: Phosphatidylserine exposing erythrocytes have been identified utilizing annexin V binding, cell volume estimated from forward scatter, cytosolic Ca2+ activity determined using Fluo-3 fluorescence, and ceramide abundance at the erythrocyte surface utilizing specific antibodies. Results: The exposure of human erythrocytes to glycochenodesoxycholic (GCDC and taurochenodesoxycholic (TCDC acid was followed by a significant decrease of forward scatter and significant increase of Fluo-3 fluorescence, ceramide abundance as well as annexin V binding. The effect on annexin V binding was significantly blunted, but not abolished by removal of extracellular Ca2+. Conclusion: Bile acids stimulate suicidal cell death, an effect paralleled by and in part due to Ca2+ entry and ceramide. The bile acid induced eryptosis may in turn lead to accelerated clearance of circulating erythrocytes and, thus, may contribute to anemia in cholestatic patients.

  18. Retinoic acids acting through retinoid receptors protect hippocampal neurons from oxygen-glucose deprivation-mediated cell death by inhibition of c-jun-N-terminal kinase and p38 mitogen-activated protein kinase.

    Science.gov (United States)

    Shinozaki, Y; Sato, Y; Koizumi, S; Ohno, Y; Nagao, T; Inoue, K

    2007-06-15

    Retinoic acids (RAs), including all-trans retinoic acid (ATRA) and 9-cis retinoic acid (9-cis RA), play fundamental roles in a variety of physiological events in vertebrates, through their specific nuclear receptors: retinoic acid receptor (RAR) and retinoid X receptor (RXR). Despite the physiological importance of RA, their functional significance under pathological conditions is not well understood. We examined the effect of ATRA on oxygen/glucose-deprivation/reperfusion (OGD/Rep)-induced neuronal damage in cultured rat hippocampal slices, and found that ATRA significantly reduced neuronal death. The cytoprotective effect of ATRA was observed not only in cornu ammonis (CA) 1 but also in CA2 and dentate gyrus (DG), and was attenuated by selective antagonists for RAR or RXR. By contrast, in the CA3 region, no protective effects of ATRA were observed. The OGD/Rep also increased phosphorylated forms of c-jun-N-terminal kinase (P-JNK) and p38 (P-p38) in hippocampus, and specific inhibitors for these kinases protected neurons. ATRA prevented the increases in P-JNK and P-p38 after OGD/Rep, as well as the decrease in NeuN and its shrinkage, all of which were inhibited by antagonists for RAR or RXR. These findings suggest that the ATRA signaling via retinoid receptors results in the inhibition of JNK and p38 activation, leading to the protection of neurons against OGD/Rep-induced damage in the rat hippocampus.

  19. Ubiquitin/proteasome pathway regulates levels of retinoic acid receptor gamma and retinoid X receptor alpha in human keratinocytes.

    Science.gov (United States)

    Boudjelal, M; Wang, Z; Voorhees, J J; Fisher, G J

    2000-04-15

    Repeated exposure of human skin to solar UV radiation leads to premature aging (photoaging) and skin cancer. UV-induced skin damage can be ameliorated by all-trans retinoic acid treatment. The actions of retinoic acid in skin keratinocytes are mediated primarily by nuclear retinoic acid receptor gamma (RARgamma) and retinoid X receptor alpha (RXRalpha). We found that exposure of cultured primary human keratinocytes to UV irradiation (30 mJ/cm2) substantially reduced (50-90%) RARgamma and RXRalpha mRNA and protein within 8 h. The rates of disappearance of RARgamma and RXRalpha proteins after UV exposure or treatment with the protein synthesis inhibitor cycloheximide were similar. UV irradiation did not increase the rate of breakdown of RARgamma or RXRalpha but rather reduced their rate of synthesis. The addition of proteasome inhibitors MG132 and LLvL, but not the lysosomal inhibitor E64, prevented loss of RARgamma and RXRalpha proteins after exposure of keratinocytes to either UV radiation or cycloheximide. Soluble extracts from nonirradiated or UV-irradiated keratinocytes possessed similar levels of proteasome activity that degraded RARgamma and RXRalpha proteins in vitro. Furthermore, RARgamma and RXRalpha were polyubiquitinated in intact cells. RXRalpha was found to contain two proline, glutamate/aspartate, serine, and threonine (PEST) motifs, which confer rapid turnover of many short-lived regulatory proteins that are degraded by the ubiquitin/proteasome pathway. However, the PEST motifs in RXRalpha did not function to regulate its stability, because deletion of the PEST motifs individually or together did not alter ubiquitination or proteasome-mediated degradation of RXRalpha. These results demonstrate that loss of RARgamma and RXRalpha proteins after UV irradiation results from degradation via the ubiquitin/proteasome pathway. Taken together, the data here indicate that ubiquitin/proteasome-mediated breakdown is an important mechanism regulating the levels of

  20. Differential expression of ETS family transcription factors in NCCIT human embryonic carcinoma cells upon retinoic acid-induced differentiation.

    Science.gov (United States)

    Park, Sung-Won; Do, Hyun-Jin; Ha, Woo Tae; Han, Mi-Hee; Song, Hyuk; Uhm, Sang-Jun; Chung, Hak-Jae; Kim, Jae-Hwan

    2014-01-01

    E26 transformation-specific (ETS) transcription factors play important roles in normal and tumorigenic processes during development, differentiation, homeostasis, proliferation, and apoptosis. To identify critical ETS factor(s) in germ cell-derived cancer cells, we examined the expression patterns of the 27 ETS transcription factors in naive and differentiated NCCIT human embryonic carcinoma cells, which exhibit both pluripotent and tumorigenic characteristics. Overall, expression of ETS factors was relatively low in NCCIT cells. Among the 27 ETS factors, polyomavirus enhancer activator 3 (PEA3) and epithelium-specific ETS transcription factor-1 (ESE-1) exhibited the most significant changes in their expression levels. Western blot analysis confirmed these patterns, revealing reduced levels of PEA3 protein and elevated levels of ESE-1 protein in differentiated cells. PEA3 increased the proportion of cells in S-phase and promoted cell growth, whereas ESE-1 reduced proliferation potential. These data suggest that PEA3 and ESE-1 may play important roles in pluripotent and tumorigenic embryonic carcinoma cells. These findings contribute to our understanding of the functions of oncogenic ETS factors in germ cell-derived stem cells during processes related to tumorigenesis and pluripotency.

  1. Retinoic acid-induced pancreatic stellate cell quiescence reduces paracrine Wnt-beta-catenin signaling to slow tumor progression

    NARCIS (Netherlands)

    Froeling, F.E.; Feig, C.; Chelala, C.; Dobson, R.; Mein, C.E.; Tuveson, D.A.; Clevers, H.; Hart, I.R.; Kocher, H.M.

    2011-01-01

    BACKGROUND & AIMS: Patients with pancreatic ductal adenocarcinoma are deficient in vitamin A, resulting in activation of pancreatic stellate cells (PSCs). We investigated whether restoration of retinol to PSCs restores their quiescence and affects adjacent cancer cells. METHODS: PSCs and cancer cell

  2. Differentiation of TERA-2 human embryonal carcinoma cells into neurons and HCMV permissive cells. Induction by agents other than retinoic acid.

    Science.gov (United States)

    Andrews, P W; Gönczöl, E; Plotkin, S A; Dignazio, M; Oosterhuis, J W

    1986-01-01

    Retinoic acid induces the differentiation of NTERA-2 cl. D1 human embryonal carcinoma (EC) cells into neurons, cells permissive for the replication of human cytomegalovirus (HCMV), and other cell types that cannot as yet be classified but are distinguishable from the stem cells. We tested several additional agents for their ability to induce the differentiation of these EC cells. No differentiation was induced by butyrate, cyclic AMP, cytosine arabinoside, the tumor promoter 12-0-tetradecanoylphorbol 13-acetate (TPA), or the chemotherapeutic agent cis-diaminedichloroplatinum, although morphological changes were detected at the highest concentrations of these agents that permitted cell survival. However, retinal, retinol, 5-bromouracil 2'deoxyribose (BUdR), 5-iodouracil 2'deoxyribose (IUdR), hexamethylene bisacetamide (HMBA), dimethylacetamide (DMA), and dimethylsulfoxide (DMSO) all induced some neuronal differentiation, but to a lesser extent than retinoic acid. Also, BUdR, IUdR, HMBA, and DMA induced the appearance of many cells permissive for the replication of HCMV. Differentiation was, in all cases, accompanied by the loss of SSEA-3, a globoseries glycolipid antigen characteristically expressed by human EC cells. However, another glycolipid antigen, A2B5, which appears in 60%-80% of differentiated cells 7 days following retinoic acid induction, was detected in less than 20% of the cells induced by the other agents studied. This implies that the HCMV-permissive cells induced by retinoic acid are not identical to those induced by BUdR, IUdR, and DMA.

  3. Retinoic Acid Signaling during Early Spinal Cord Development

    Directory of Open Access Journals (Sweden)

    Ruth Diez del Corral

    2014-06-01

    Full Text Available Retinoic acid signaling is required at several steps during the development of the spinal cord, from the specification of generic properties to the final acquisition of neuronal subtype identities, including its role in trunk neural crest development. These functions are associated with the production of retinoic acid in specific tissues and are highly dependent on context. Here, we review the defects associated with retinoic acid signaling manipulations, mostly in chick and mouse models, trying to separate the different processes where retinoic acid signaling is involved and to highlight common features, such as its ability to promote transitions along the neuronal differentiation cascade.

  4. Eosinophils from Murine Lamina Propria Induce Differentiation of Naive T Cells into Regulatory T Cells via TGF-β1 and Retinoic Acid.

    Directory of Open Access Journals (Sweden)

    Hong-Hu Chen

    Full Text Available Treg cells play a crucial role in immune tolerance, but mechanisms that induce Treg cells are poorly understood. We here have described eosinophils in lamina propria (LP that displayed high aldehyde dehydrogenase (ALDH activity, a rate-limiting step during all-trans retinoic acid (ATRA synthesis, and expressed TGF-β1 mRNA and high levels of ATRA. Co-incubation assay confirmed that LP eosinophils induced the differentiation of naïve T cells into Treg cells. Differentiation promoted by LP eosinophils were inhibited by blocked either TGF-β1 or ATRA. Peripheral blood (PB eosinophils did not produce ATRA and could not induce Treg differentiation. These data identifies LP eosinophils as effective inducers of Treg cell differentiation through a mechanism dependent on TGF-β1 and ATRA.

  5. 超临界CO_2密度对全反式番茄红素吸光系数的影响%Effect of Supercritical Carbon Dioxide Density on Absorption Coefficient of All-trans Lycopene

    Institute of Scientific and Technical Information of China (English)

    何强强; 惠伯棣; 宫平

    2012-01-01

    Objective: To assess the effect of varying carbon dioxide density on absorption coefficient(A1cm) of all-trans lycopene through exploring the correlation between carbon dioxide density in supercritical fluid chromatography(SFC) and peak areas of all-trans lycopene fractions.Methods: Supercritical CO2fluid chromatography was carried out on a Diamonsil C8(250mm × 4.6 mm,5 μm,) at a pressure ranging from 11.5 to 17.5 MPa,and a temperature ranging from 35—55 ℃.The detection wavelength was 453 nm,and 20 μL sample was injected for SFC chromatography.Results: Peak area of all-trans lycopene at the maximum absorption wavelength in supercritical carbon dioxide fluid chromatography revealed a variation and was linearly positive correlated with the density of carbon dioxide.Conclusion: Absorption coefficient of all-trans lycopene is positively correlated with the density of supercritical carbon dioxide.%目的:通过在超临界CO2色谱上测定CO2流动相密度与全反式番茄红素组分峰面积的相关性,推算二氧化碳密度变化对全反式番茄红素的吸光系数(A1cm)的影响。方法:超临界色谱条件:色谱柱:Diamonsil C8(250mm×4.6m m,5μm);检测波长:4 5 3 n m;压力变化范围:1 1.5~1 7.5 M P a;温度变化范围:3 5~5 5℃;流速:2mL/min;进样量:20μL。结果:全反式番茄红素组分在超临界CO2中最大吸收波长处的峰面积是可变的,与CO2密度呈线性正相关。结论:可推断全反式番茄红素吸光系数与超临界CO2流体密度变化呈正相关。

  6. Liver-specific cytochrome P450 CYP2C22 is a direct target of retinoic acid and a retinoic acid-metabolizing enzyme in rat liver.

    Science.gov (United States)

    Qian, Linxi; Zolfaghari, Reza; Ross, A Catharine

    2010-07-01

    Several cytochrome P450 (CYP) enzymes catalyze the C4-hydroxylation of retinoic acid (RA), a potent inducer of cell differentiation and an agent in the treatment of several diseases. Here, we have characterized CYP2C22, a member of the rat CYP2C family with homology to human CYP2C8 and CYP2C9. CYP2C22 was expressed nearly exclusively in hepatocytes, where it was one of the more abundant mRNAs transcripts. In H-4-II-E rat hepatoma cells, CYP2C22 mRNA was upregulated by all-trans (at)-RA, and Am580, a nonmetabolizable analog of at-RA. In comparison, in primary human hepatocytes, at-RA increased CYP2C9 but not CYP2C8 mRNA. Analysis of the CYP2C22 promoter region revealed a RA response element (5'-GGTTCA-(n)5-AGGTCA-3') in the distal flanking region, which bound the nuclear hormone receptors RAR and RXR and which was required for transcriptional activation response of this promoter to RA in CYP2C22-luciferase-transfected RA-treated HepG2 cells. The cDNA-expressed CYP2C22 protein metabolized [3H]at-RA to more polar metabolites. While long-chain polyunsaturated fatty acids competed, 9-cis-RA was a stronger competitor. Our studies demonstrate that CYP2C22 is a high-abundance, retinoid-inducible, hepatic P450 with the potential to metabolize at-RA, providing additional insight into the role of the CYP2C gene family in retinoid homeostasis.

  7. Establishment of a GM-CSF-dependent megakaryoblastic cell line with the potential to differentiate into an eosinophilic lineage in response to retinoic acids.

    Science.gov (United States)

    Ma, F; Koike, K; Higuchi, T; Kinoshita, T; Takeuchi, K; Mwamtemi, H H; Sawai, N; Kamijo, T; Shiohara, M; Horie, S; Kawa, S; Sasaki, Y; Hidaka, E; Yamagami, O; Yamashita, T; Koike, T; Ishii, E; Komiyama, A

    1998-02-01

    We recently established a human granulocyte-macrophage colony-stimulating factor (GM-CSF)-dependent cell line (HML) from colony-constituent cells grown by peripheral blood cells of a patient with acute megakaryoblastic leukaemia. The HML cells possessed megakaryocytic features, as determined by cytochemical, electron microscopic and flow cytometric analysis. In the present study we examined the effects of retinoic acid (RA) on the development of HML cells. All-trans-RA, 13-cis-RA and 9-cis-RA at 10(-8) mol/l to 10(-5) mol/l inhibited the GM-CSF-dependent cell growth. Some of the RA-treated cells contained prominent azurophilic granules and were positive for peroxidase. They also reacted with Biebrich scarlet, Luxol fast blue and a monoclonal antibody against eosinophil peroxidase. In addition, exposure to RA increased the frequency and the intensity of major basic protein-positive cells. However, eosinophil-derived neurotoxin and eosinophil cationic protein were not detected or were only detected at a low level in the lysates of the HML cells treated with RA. Although IL-5 alone could not stimulate cell growth, the addition of IL-5 to the cultures containing stem cell factor + all-trans-RA was required for the expression of the eosinophilic phenotype. These results suggest that the HML cell line is a megakaryoblastic cell line with the potential to differentiate into the eosinophilic lineage. HML cells may be a useful model for elucidating the eosinophilic differentiation programme.

  8. Galactomutarotase and other galactose-related genes are rapidly induced by retinoic acid in human myeloid cells.

    Science.gov (United States)

    Pai, Tongkun; Chen, Qiuyan; Zhang, Yao; Zolfaghari, Reza; Ross, A Catharine

    2007-12-25

    Aldose-1-epimerase (mutarotase) catalyzes the interconversion of alpha and beta hexoses, which is essential for normal carbohydrate metabolism and the production of complex oligosaccharides. Galactose mutarotase (GALM) has been well characterized at the protein level, but information is lacking on the regulation of GALM gene expression. We report herein that all-trans-retinoic acid (RA), an active metabolite of vitamin A that is known to induce myeloid lineage cell differentiation into macrophage-like cells, induces a rapid and robust regulation of GALM mRNA expression in human myeloid cells. all-trans-RA at a physiological concentration (20 nM), or Am580, a ligand selective for the nuclear retinoid receptor RARalpha, increased GALM mRNA in THP-1 cells, with significantly increased expression in 2 h, increasing further to an approximately 8-fold elevation after 6-40 h (P < 0.005). In contrast, tumor necrosis factor-alpha did not increase GALM mRNA expression, although it is capable of inducing cell differentiation. RA also increased GALM mRNA in U937 and HL-60 cells. The increase in GALM mRNA by RA was blocked by pretreating THP-1 cells with actinomycin D but not by cycloheximide. GALM protein and mutarotase activity were also increased time dependently in RA-treated THP-1 cells. In addition to GALM, several other genes in the biosynthetic pathway of galactosyl-containing complex oligosaccharides were more highly expressed in RA-treated THP-1 cells, including B4GALT5, ST3GAL3, ST6GALNAC5, and GALNAC4S-6ST. Thus, the results of this study identify RA as a significant regulator of GALM and other galactose-related genes in myeloid-monocytic cells, which could affect energy utilization and synthesis of cell-surface glycoproteins or glycolipids involved in cell motility, adhesion, and/or functional properties.

  9. Sec61alpha synthesis is enhanced during translocation of nascent chains of collagen type IV in F9 teratocarcinoma cells after retinoic acid treatment

    Directory of Open Access Journals (Sweden)

    L.R. Ferreira

    2003-01-01

    Full Text Available Nascent procollagen peptides and other secretory proteins are transported across the endoplasmic reticulum (ER membrane through a protein-conducting channel called translocon. Sec61alpha, a multispanning membrane translocon protein, has been implicated as being essential for translocation of polypeptide chains into the cisterns of the ER. Sec61alpha forms a protein complex with collagen and Hsp47, an ER-resident heat shock protein that binds specifically to collagen. However, it is not known whether Sec61alpha is ubiquitously produced in collagen-producing F9 teratocarcinoma cells or under heat shock treatment. Furthermore, the production and utilization of Sec61alpha may depend on the stage of cell differentiation. Cultured F9 teratocarcinoma cells are capable of differentiation in response to low concentrations of retinoic acid. This differentiation results in loss of tumorigenicity. Mouse F9 cells were grown in culture medium at 37ºC and 43ºC (heat shock treatment treated or not with retinoic acid, and labeled in certain instances with 35S-methionine. Membrane-bound polysomes of procollagen IV were then isolated. Immunoprecipitation and Western blot analysis were performed using polyclonal antibodies against collagen IV, Hsp47 and Sec61alpha. Under retinoic acid-untreated conditions, F9 cells produced undetectable amounts of Sec61alpha. Sec61alpha, Hsp47 and type IV collagen levels were increased after retinoic acid treatment. Heat shock treatment did not alter Sec61alpha levels, suggesting that Sec61alpha production is probably not affected by heat shock. These data indicate that the enhanced production of Sec61alpha in retinoic acid-induced F9 teratocarcinoma cells parallels the increased synthesis of Hsp47 and collagen type IV.

  10. Expression and Subcellular Localization of Retinoic Acid Receptor-α (RARα) in Healthy and Varicocele Human Spermatozoa: Its Possible Regulatory Role in Capacitation and Survival.

    Science.gov (United States)

    Perrotta, Ida; Perri, Mariarita; Santoro, Marta; Panza, Salvatore; Caroleo, Maria C; Guido, Carmela; Mete, Annamaria; Cione, Erika; Aquila, Saveria

    2015-01-01

    Varicocele, an abnormal tortuosity and dilation of veins of the pampiniform plexus, is the most common identifiable and correctable cause of male infertility. It is now becoming apparent that signaling through vitamin A metabolites, such as all-trans retinoic acid (ATRA), is indispensable for spermatogenesis and disruption of retinoic acid receptor-α (RARα) function may result in male sterility and aberrant spermatogenesis. Herein, we investigated by Western blot and immunogold electron microscopy the expression profiles and subcellular localization of RARα in healthy and varicocele human sperm; in addition, we analyzed the effects of ATRA on cholesterol efflux and sperm survival utilizing enzymatic colorimetric CHOD-PAP method and Eosin Y technique, respectively. In varicocele samples, a strong reduction of RARα expression was observed. Immunogold labeling evidenced cellular location of RARα also confirming its reduced expression in "varicocele" samples. Sperm responsiveness to ATRA treatment was reduced in varicocele sperm. Our study showed that RARα is expressed in human sperm probably with a dual role in promoting both cholesterol efflux and survival. RARα might be involved in the pathogenesis of varicocele as its expression is reduced in pathologic samples. Thus, ATRA administration in procedures for artificial insemination or dietary vitamin A supplementation might represent a promising therapeutic approach for the management of male infertility.

  11. Nanosecond pulsed electric field suppresses development of eyes and germ cells through blocking synthesis of retinoic acid in Medaka (Oryzias latipes.

    Directory of Open Access Journals (Sweden)

    Eri Shiraishi

    Full Text Available Application of nanosecond pulsed electric fields (nsPEFs has attracted rising attention in various scientific fields including medical, pharmacological, and biological sciences, although its effects and molecular mechanisms leading to the effects remain poorly understood. Here, we show that a single, high-intensity (10-30 kV/cm, 60-ns PEF exposure affects gene expression and impairs development of eyes and germ cells in medaka (Oryzias latipes. Exposure of early blastula stage embryos to nsPEF down-regulated the expression of several transcription factors which are essential for eye development, causing abnormal eye formation. Moreover, the majority of the exposed genetic female embryos showed a fewer number of germ cells similar to that of the control (unexposed genetic male at 9 days post-fertilization (dpf. However, all-trans retinoic acid (atRA treatment following the exposure rescued proliferation of germ cells and resumption of normal eye development, suggesting that the phenotypes induced by nsPEF are caused by a decrease of retinoic acid levels. These results confirm that nsPEFs induce novel effects during embryogenesis in medaka.

  12. Nicotinamide attenuates aquaporin 3 overexpression induced by retinoic acid through inhibition of EGFR/ERK in cultured human skin keratinocytes.

    Science.gov (United States)

    Song, Xiuzu; Xu, Aie; Pan, Wei; Wallin, Brittany; Kivlin, Rebecca; Lu, Shan; Cao, Cong; Bi, Zhigang; Wan, Yinsheng

    2008-08-01

    The most common adverse effects that are related to all-trans retinoic acid (atRA) treatment are irritation and dryness of the skin. atRA therapy is reported to impair barrier function as achieved by trans-epidermal water loss (TEWL). Treatment with nicotinamide prior to initiation of atRA therapy provides additional barrier protection and thus reduces susceptibility of retinoic acid. Our previous studies showed that atRA upregulates aquaporin 3 (AQP3) in cultured human skin keratinocytes and fibroblasts. Others have demonstrated that in atopic dermatitis, overexpression of AQP3 is linked to elevated TEWL and that nicotinamide treatment reduces skin TEWL. In this study, we observed that while atRA upregulates AQP3 expression in cultured human skin keratinocytes (HaCaT cells), nicotinamide attenuates the effect of atRA in a concentration-dependent manner. atRA treatment induces EGFR and ERK activation. PD153035, an EGFR inhibitor, and U0126, an ERK inhibitor, inhibit atRA-induced upregulation of AQP3. Nicotinamide also inhibits atRA-induced activation of EGFR/ERK signal transduction and decreases water permeability by downregulating AQP3 expression. Collectively, our results indicate that the effect of atRA on AQP3 expression is at least partly mediated by EGFR/ERK signaling in cultured human skin keratinocytes. Nicotinamide attenuates atRA-induced AQP3 expression through inhibition of EGFR/ERK signal transduction and eventually decreases water permeability and water loss. Our study provides insights into the molecular mechanism through which nicotinamide reverses the side effects of dryness in human skin after treatment with atRA.

  13. Retinoic acid therapy resistance progresses from unilineage to bilineage in HL-60 leukemic blasts.

    Directory of Open Access Journals (Sweden)

    Holly A Jensen

    Full Text Available Emergent resistance can be progressive and driven by global signaling aberrations. All-trans retinoic acid (RA is the standard therapeutic agent for acute promyelocytic leukemia, but 10-20% of patients are not responsive, and initially responsive patients relapse and develop retinoic acid resistance. The patient-derived, lineage-bipotent acute myeloblastic leukemia (FAB M2 HL-60 cell line is a potent tool for characterizing differentiation-induction therapy responsiveness and resistance in t(15;17-negative cells. Wild-type (WT HL-60 cells undergo RA-induced granulocytic differentiation, or monocytic differentiation in response to 1,25-dihydroxyvitamin D3 (D3. Two sequentially emergent RA-resistant HL-60 cell lines, R38+ and R38-, distinguishable by RA-inducible CD38 expression, do not arrest in G1/G0 and fail to upregulate CD11b and the myeloid-associated signaling factors Vav1, c-Cbl, Lyn, Fgr, and c-Raf after RA treatment. Here, we show that the R38+ and R38- HL-60 cell lines display a progressive reduced response to D3-induced differentiation therapy. Exploiting the biphasic dynamic of induced HL-60 differentiation, we examined if resistance-related defects occurred during the first 24 h (the early or "precommitment" phase or subsequently (the late or "lineage-commitment" phase. HL-60 were treated with RA or D3 for 24 h, washed and retreated with either the same, different, or no differentiation agent. Using flow cytometry, D3 was able to induce CD38, CD11b and CD14 expression, and G1/G0 arrest when present during the lineage-commitment stage in R38+ cells, and to a lesser degree in R38- cells. Clustering analysis of cytometry and quantified Western blot data indicated that WT, R38+ and R38- HL-60 cells exhibited decreasing correlation between phenotypic markers and signaling factor expression. Thus differentiation induction therapy resistance can develop in stages, with initial partial RA resistance and moderate vitamin D3 responsiveness

  14. Retinoic acid therapy resistance progresses from unilineage to bilineage in HL-60 leukemic blasts.

    Science.gov (United States)

    Jensen, Holly A; Bunaciu, Rodica P; Ibabao, Christopher N; Myers, Rebecca; Varner, Jeffrey D; Yen, Andrew

    2014-01-01

    Emergent resistance can be progressive and driven by global signaling aberrations. All-trans retinoic acid (RA) is the standard therapeutic agent for acute promyelocytic leukemia, but 10-20% of patients are not responsive, and initially responsive patients relapse and develop retinoic acid resistance. The patient-derived, lineage-bipotent acute myeloblastic leukemia (FAB M2) HL-60 cell line is a potent tool for characterizing differentiation-induction therapy responsiveness and resistance in t(15;17)-negative cells. Wild-type (WT) HL-60 cells undergo RA-induced granulocytic differentiation, or monocytic differentiation in response to 1,25-dihydroxyvitamin D3 (D3). Two sequentially emergent RA-resistant HL-60 cell lines, R38+ and R38-, distinguishable by RA-inducible CD38 expression, do not arrest in G1/G0 and fail to upregulate CD11b and the myeloid-associated signaling factors Vav1, c-Cbl, Lyn, Fgr, and c-Raf after RA treatment. Here, we show that the R38+ and R38- HL-60 cell lines display a progressive reduced response to D3-induced differentiation therapy. Exploiting the biphasic dynamic of induced HL-60 differentiation, we examined if resistance-related defects occurred during the first 24 h (the early or "precommitment" phase) or subsequently (the late or "lineage-commitment" phase). HL-60 were treated with RA or D3 for 24 h, washed and retreated with either the same, different, or no differentiation agent. Using flow cytometry, D3 was able to induce CD38, CD11b and CD14 expression, and G1/G0 arrest when present during the lineage-commitment stage in R38+ cells, and to a lesser degree in R38- cells. Clustering analysis of cytometry and quantified Western blot data indicated that WT, R38+ and R38- HL-60 cells exhibited decreasing correlation between phenotypic markers and signaling factor expression. Thus differentiation induction therapy resistance can develop in stages, with initial partial RA resistance and moderate vitamin D3 responsiveness (unilineage

  15. Retinoic acid-mediated gene expression in transgenic reporter zebrafish.

    Science.gov (United States)

    Perz-Edwards, A; Hardison, N L; Linney, E

    2001-01-01

    Retinoic acid-mediated gene activation is important for normal vertebrate development. The size and nature of retinoic acid make it difficult to identify the precise cellular location of this signaling molecule throughout an embryo. Additionally, retinoic acid (RA) signaling is regulated by a complex combination of receptors, coactivators, and antagonizing proteins. Thus, in order to integrate these signals and identify regions within a whole developing embryo where cells can respond transcriptionally to retinoic acid, we have used a reporter transgenic approach. We have generated several stable lines of transgenic zebrafish which use retinoic acid response elements to drive fluorescent protein expression. In these zebrafish lines, transgene expression is localized to regions of the neural tube, retina, notochord, somites, heart, pronephric ducts, branchial arches, and jaw muscles in embryos and larvae. Transgene expression can be induced in additional regions of the neural tube and retina as well as the immature notochord, hatching gland, enveloping cell layer, and fin by exposing embryos to retinoic acid. Treatment with retinoic acid synthase inhibitors, citral and diethylaminobenzaldehyde (DEAB), during neurulation, greatly reduces transgene expression. DEAB treatment of embryos at gastrulation phenocopies the embryonic effects of vitamin A deprivation or targeted disruption of the RA synthase retinaldehyde dehydrogenase-2 in other vertebrates. Together these data suggest that the reporter expression we see in zebrafish is dependent upon conserved vertebrate pathways of RA synthesis.

  16. Molecular recognition of CYP26A1 binding pockets and structure-activity relationship studies for design of potent and selective retinoic acid metabolism blocking agents.

    Science.gov (United States)

    Sun, Bin; Song, Shuai; Hao, Chen-Zhou; Huang, Wan-Xu; Liu, Chun-Chi; Xie, Hong-Lei; Lin, Bin; Cheng, Mao-Sheng; Zhao, Dong-Mei

    2015-03-01

    All-trans-retinoic acid (ATRA), the biologically most active metabolite of vitamin A, plays a major role in the regulation of cellular differentiation and proliferation, and it is also an important pharmacological agent particularly used in the treatment of cancer, skin, neurodegenerative and autoimmune diseases. However, ATRA is very easy to be metabolized into 4-hydroxyl-RA in vivo by CYP26A1, an inducible cytochrome P450 enzyme, eventually into more polar metabolites. Therefore, it is vital to develop specific retinoic acid metabolism blocking agents (RAMBAs) to inhibit the metabolic enzyme CYP26A1 in the treatment of relevant diseases aforementioned. In this study, CYP26A1 and its interactions with retinoic acid-competitive metabolism blocking agents were investigated by a combined ligand- and structure-based approach. First, since the crystal structure of CYP26A1 protein has not been determined, we constructed the 3D structure of CYP26A1 using homology modeling. In order to achieve a deeper insight into the mode of action of RAMBAs in the active site, the molecular superimposition model and the common feature pharmacophore model were constructed, and molecular docking was performed. The molecular superimposition model is composed of three features: the main chain groups, side chain groups, and azole groups. The common feature pharmacophore model consists of five chemical features: four hydrophobic groups and one hydrogen acceptor (HHHHA). The results of molecular docking show that the characteristic groups of RAMBAs were mapped into three different active pockets, respectively. A structure-activity relationship (SAR) was obtained by a combination of the molecular superimposition and docking results with the pharmacophore model. This study gives more insight into the interaction model inside the CYP26A1 active site and provides guidance for the design of more potent and possibly more selective RAMBAs.

  17. Effects of retinoic acid on growth hormone-releasing hormone receptor, growth hormone secretagogue receptor gene expression and growth hormone secretion in rat anterior pituitary cells.

    Science.gov (United States)

    Maliza, Rita; Fujiwara, Ken; Tsukada, Takehiro; Azuma, Morio; Kikuchi, Motoshi; Yashiro, Takashi

    2016-06-30

    Retinoic acid (RA) is an important signaling molecule in embryonic development and adult tissue. The actions of RA are mediated by the nuclear receptors retinoic acid receptor (RAR) and retinoid X receptor (RXR), which regulate gene expression. RAR and RXR are widely expressed in the anterior pituitary gland. RA was reported to stimulate growth hormone (GH) gene expression in the anterior pituitary cells. However, current evidence is unclear on the role of RA in gene expression of growth hormone-releasing hormone receptor (Ghrh-r), growth hormone secretagogue receptor (Ghs-r) and somatostatin receptors (Sst-rs). Using isolated anterior pituitary cells of rats, we examined the effects of RA on gene expression of these receptors and GH release. Quantitative real-time PCR revealed that treatment with all-trans retinoic acid (ATRA; 10(-6) M) for 24 h increased gene expression levels of Ghrh-r and Ghs-r; however, expressions of Sst-r2 and Sst-r5 were unchanged. Combination treatment with the RAR-agonist Am80 and RXR-agonist PA024 mimicked the effects of ATRA on Ghrh-r and Ghs-r gene expressions. Exposure of isolated pituitary cells to ATRA had no effect on basal GH release. In contrast, ATRA increased growth hormone-releasing hormone (GHRH)- and ghrelin-stimulated GH release from cultured anterior pituitary cells. Our results suggest that expressions of Ghrh-r and Ghs-r are regulated by RA through the RAR-RXR receptor complex and that RA enhances the effects of GHRH and ghrelin on GH release from the anterior pituitary gland.

  18. Induced differentiation of human myeloid leukemia cells into M2 macrophages by combined treatment with retinoic acid and 1α,25-dihydroxyvitamin D3.

    Directory of Open Access Journals (Sweden)

    Hiromichi Takahashi

    Full Text Available Retinoids and 1α,25-dihydroxyvitamin D3 (1,25(OH2D3 induce differentiation of myeloid leukemia cells into granulocyte and macrophage lineages, respectively. All-trans retinoic acid (ATRA, which is effective in the treatment of acute promyelocytic leukemia, can induce differentiation of other types of myeloid leukemia cells, and combined treatment with retinoid and 1,25(OH2D3 effectively enhances the differentiation of leukemia cells into macrophage-like cells. Recent work has classified macrophages into M1 and M2 types. In this study, we investigated the effect of combined treatment with retinoid and 1,25(OH2D3 on differentiation of myeloid leukemia THP-1 and HL60 cells. 9-cis Retinoic acid (9cRA plus 1,25(OH2D3 inhibited proliferation of THP-1 and HL60 cells and increased myeloid differentiation markers including nitroblue tetrazolium reducing activity and expression of CD14 and CD11b. ATRA and the synthetic retinoic acid receptor agonist Am80 exhibited similar effects in combination with 1,25(OH2D3 but less effectively than 9cRA, while the retinoid X receptor agonist HX630 was not effective. 9cRA plus 1,25(OH2D3 effectively increased expression of M2 macrophage marker genes, such as CD163, ARG1 and IL10, increased surface CD163 expression, and induced interleukin-10 secretion in myeloid leukemia cells, while 9cRA alone had weaker effects on these phenotypes and 1,25(OH2D3 was not effective. Taken together, our results demonstrate selective induction of M2 macrophage markers in human myeloid leukemia cells by combined treatment with 9cRA and 1,25(OH2D3.

  19. Retinoic acid-treated pluripotent stem cells undergoing neurogenesis present increased aneuploidy and micronuclei formation.

    Directory of Open Access Journals (Sweden)

    Rafaela C Sartore

    Full Text Available The existence of loss and gain of chromosomes, known as aneuploidy, has been previously described within the central nervous system. During development, at least one-third of neural progenitor cells (NPCs are aneuploid. Notably, aneuploid NPCs may survive and functionally integrate into the mature neural circuitry. Given the unanswered significance of this phenomenon, we tested the hypothesis that neural differentiation induced by all-trans retinoic acid (RA in pluripotent stem cells is accompanied by increased levels of aneuploidy, as previously described for cortical NPCs in vivo. In this work we used embryonal carcinoma (EC cells, embryonic stem (ES cells and induced pluripotent stem (iPS cells undergoing differentiation into NPCs. Ploidy analysis revealed a 2-fold increase in the rate of aneuploidy, with the prevalence of chromosome loss in RA primed stem cells when compared to naïve cells. In an attempt to understand the basis of neurogenic aneuploidy, micronuclei formation and survivin expression was assessed in pluripotent stem cells exposed to RA. RA increased micronuclei occurrence by almost 2-fold while decreased survivin expression by 50%, indicating possible mechanisms by which stem cells lose their chromosomes during neural differentiation. DNA fragmentation analysis demonstrated no increase in apoptosis on embryoid bodies treated with RA, indicating that cell death is not the mandatory fate of aneuploid NPCs derived from pluripotent cells. In order to exclude that the increase in aneuploidy was a spurious consequence of RA treatment, not related to neurogenesis, mouse embryonic fibroblasts were treated with RA under the same conditions and no alterations in chromosome gain or loss were observed. These findings indicate a correlation amongst neural differentiation, aneuploidy, micronuclei formation and survivin downregulation in pluripotent stem cells exposed to RA, providing evidence that somatically generated chromosomal

  20. RETINOIC ACID DOWN-REGULATES BONE MORPHOGENETIC PROTEIN 7 EXPRESSION IN RAT WITH CLEFT PALATE

    Institute of Scientific and Technical Information of China (English)

    Lei Guo; Yu-yan Zhao; Shi-liang Zhang; Kui Liu; Xiao-yu Gao

    2008-01-01

    Objective To evaluate the effects of retinoic acid (RA) on expression of bone morphogenetic protein 7 (BMP-7)in rat fetus with cleft palate, and the effects of RA on proliferation and apoptosis of osteoblasts. Methods All-trans RA (ATRA) was used to induce congenital cleft palate in Wistar rat. BMP-7 mRNA expres-sion in maxillary bone tissue of fetal rats was measured by Northern blotting analysis. Flow cytometry and MTT assay were used to measure the apoptosis and proliferation of ATRA-treated MC-3T3-E1 cells. BMP-7 mRNA and protein ex-pressions in ATRA-treated MC-3T3-E1 cells were detected by RT-PCR and Western blotting analysis.Results ATRA could induce cleft palate of rat fetus. The incidence rate of cleft palate induced by 100 mg/kg AT-RA (45.5%) was significantly higher than 50 mg/kg ATRA (12.5%, P<0.05). BMP-7 mRNA expression de-creased in maxillary bone tissue of rat fetus with cleft palate. MC-3T3-E1 cells proliferation treated with 1 × 10-6 mol/L ATRA decreased by 60%, the cell apoptosis increased by 2 times. BMP-7 mR.NA and protein levels in MC-3T3-E1cells treated with 1 × 10-6 mol/L ATRA decreased by 60% and 80%, respectively, compared with ATRA-untreated ceils (P<0.05).Conclusions BMP-7 may play an important role in embryonic palate development RA may possess the ability to down-regulate cell proliferation through regulation of BMP-7 gene expression.

  1. An alternative retinoic acid-responsive Stra6 promoter regulated in response to retinol deficiency.

    Science.gov (United States)

    Laursen, Kristian B; Kashyap, Vasundhra; Scandura, Joseph; Gudas, Lorraine J

    2015-02-13

    Cellular uptake of vitamin A (retinol) is essential for many biological functions. The Stra6 protein binds the serum retinol-binding protein, RBP4, and acts in conjunction with the enzyme lecithin:retinol acyltransferase to facilitate retinol uptake in some cell types. We show that in embryonic stem (ES) cells and in some tissues, the Stra6 gene encodes two distinct mRNAs transcribed from two different promoters. Whereas both are all-trans-retinoic acid (RA)-responsive in ES cells, the downstream promoter contains a half-site RA response element (RARE) and drives an ∼ 13-fold, RA-associated increase in luciferase reporter activity. We employed CRISPR-Cas9 genome editing to show that the endogenous RARE is required for RA-induced transcription of both Stra6 isoforms. We further demonstrate that in ES cells, 1) both RARγ and RXRα are present at the Stra6 RARE; 2) RA increases co-activator p300 (KAT3B) binding and histone H3 Lys-27 acetylation at both promoters; 3) RA decreases Suz12 levels and histone H3 Lys-27 trimethylation epigenetic marks at both promoters; and 4) these epigenetic changes are diminished in the absence of RARγ. In the brains of WT mice, both the longer and the shorter Stra6 transcript (Stra6L and Stra6S, respectively) are highly expressed, whereas these transcripts are found only at low levels in RARγ(-/-) mice. In the brains of vitamin A-deficient mice, both Stra6L and Stra6S levels are decreased. In contrast, in the vitamin A-deficient kidneys, the Stra6L levels are greatly increased, whereas Stra6S levels are decreased. Our data show that kidneys respond to retinol deficiency by differential Stra6 promoter usage, which may play a role in the retention of retinol when vitamin A is low.

  2. Efficient differentiation of embryonic stem cells into mesodermal precursors by BMP, retinoic acid and Notch signalling.

    Directory of Open Access Journals (Sweden)

    Josema Torres

    Full Text Available The ability to direct differentiation of mouse embryonic stem (ES cells into specific lineages not only provides new insights into the pathways that regulate lineage selection but also has translational applications, for example in drug discovery. We set out to develop a method of differentiating ES cells into mesodermal cells at high efficiency without first having to induce embryoid body formation. ES cells were plated on a feeder layer of PA6 cells, which have membrane-associated stromal-derived inducing activity (SDIA, the molecular basis of which is currently unknown. Stimulation of ES/PA6 co-cultures with Bone Morphogenetic Protein 4 (BMP4 both favoured self-renewal of ES cells and induced differentiation into a Desmin and Nestin double positive cell population. Combined stimulation with BMP4 and all-trans Retinoic Acid (RA inhibited self-renewal and resulted in 90% of cells expressing Desmin and Nestin. Quantitative reverse transcription-polymerase chain reaction (qPCR analysis confirmed that the cells were of mesodermal origin and expressed markers of mesenchymal and smooth muscle cells. BMP4 activation of a MAD-homolog (Smad-dependent reporter in undifferentiated ES cells was attenuated by co-stimulation with RA and co-culture with PA6 cells. The Notch ligand Jag1 was expressed in PA6 cells and inhibition of Notch signalling blocked the differentiation inducing activity of PA6 cells. Our data suggest that mesodermal differentiation is regulated by the level of Smad activity as a result of inputs from BMP4, RA and the Notch pathway.

  3. Retinoic acid treatment enhances lipid oxidation and inhibits lipid biosynthesis capacities in the liver of mice.

    Science.gov (United States)

    Amengual, Jaume; Ribot, Joan; Bonet, M Luisa; Palou, Andreu

    2010-01-01

    Vitamin A, mainly as retinoic acid (RA), is known to affect the development and function of adipose tissues. Treatment with RA reduces body weight and adiposity independent of changes in food intake in mice. Lipid metabolism in liver can have a major impact on whole body adiposity. The aim of this work was to investigate the effects of an in vivo treatment with RA on hepatic lipid metabolism in mice. Adult, standard diet-fed mice were treated with different doses of all-trans RA or vehicle (subcutaneous injection) for 4 days before sacrifice. Food intake and body weight changes during treatment were determined, as well as adiposity, liver composition, levels of circulating metabolites and lipoproteins and expression levels of key mRNA species in liver following sacrifice. RA treatment resulted in reduced body weight and adiposity, as expected. In the liver, RA treatment triggered an increase in the mRNA expression levels of peroxisome proliferator-activated receptor alpha, retinoid X receptor alpha, uncoupling protein 2, liver-type carnitine palmitoyltransferase 1, and carnitine/acylcarnitine carrier, and a reduction in the mRNA expression levels of sterol regulatory element binding protein 1c and fatty acid synthase. Consistent with the changes in gene expression, hepatic triacylglycerol content and circulating VLDL fraction were reduced and levels of circulating ketone bodies increased after RA treatment. These results point to a capacity of active vitamin A forms to shift liver lipid metabolism in vivo towards increased catabolism and reduced lipogenesis. These effects might contribute to the reduction of adiposity brought about by RA treatment.

  4. Polydimethylsiloxane (PDMS) modulates CD38 expression, absorbs retinoic acid and may perturb retinoid signalling.

    Science.gov (United States)

    Futrega, Kathryn; Yu, Jianshi; Jones, Jace W; Kane, Maureen A; Lott, William B; Atkinson, Kerry; Doran, Michael R

    2016-04-21

    Polydimethylsiloxane (PDMS) is the most commonly used material in the manufacture of customized cell culture devices. While there is concern that uncured PDMS oligomers may leach into culture medium and/or hydrophobic molecules may be absorbed into PDMS structures, there is no consensus on how or if PDMS influences cell behaviour. We observed that human umbilical cord blood (CB)-derived CD34(+) cells expanded in standard culture medium on PDMS exhibit reduced CD38 surface expression, relative to cells cultured on tissue culture polystyrene (TCP). All-trans retinoic acid (ATRA) induces CD38 expression, and we reasoned that this hydrophobic molecule might be absorbed by PDMS. Through a series of experiments we demonstrated that ATRA-mediated CD38 expression was attenuated when cultures were maintained on PDMS. Medium pre-incubated on PDMS for extended durations resulted in a time-dependant reduction of ATRA in the medium and increasingly attenuated CD38 expression. This indicated a time-dependent absorption of ATRA into the PDMS. To better understand how PDMS might generally influence cell behaviour, Ingenuity Pathway Analysis (IPA) was used to identify potential upstream regulators. This analysis was performed for differentially expressed genes in primary cells including CD34(+) haematopoietic progenitor cells, mesenchymal stromal cells (MSC), and keratinocytes, and cell lines including prostate cancer epithelial cells (LNCaP), breast cancer epithelial cells (MCF-7), and myeloid leukaemia cells (KG1a). IPA predicted that the most likely common upstream regulator of perturbed pathways was ATRA. We demonstrate here that ATRA is absorbed by PDMS in a time-dependent manner and results in the concomitant reduced expression of CD38 on the cell surface of CB-derived CD34(+) cells.

  5. Retinoic acid synthesis and functions in early embryonic development

    Directory of Open Access Journals (Sweden)

    Kam Richard Kin Ting

    2012-03-01

    Full Text Available Abstract Retinoic acid (RA is a morphogen derived from retinol (vitamin A that plays important roles in cell growth, differentiation, and organogenesis. The production of RA from retinol requires two consecutive enzymatic reactions catalyzed by different sets of dehydrogenases. The retinol is first oxidized into retinal, which is then oxidized into RA. The RA interacts with retinoic acid receptor (RAR and retinoic acid X receptor (RXR which then regulate the target gene expression. In this review, we have discussed the metabolism of RA and the important components of RA signaling pathway, and highlighted current understanding of the functions of RA during early embryonic development.

  6. Phenothiourea sensitizes zebrafish cranial neural crest and extraocular muscle development to changes in retinoic acid and IGF signaling.

    Directory of Open Access Journals (Sweden)

    Brenda L Bohnsack

    Full Text Available 1-Phenyl 2-thiourea (PTU is a tyrosinase inhibitor commonly used to block pigmentation and aid visualization of zebrafish development. At the standard concentration of 0.003% (200 µM, PTU inhibits melanogenesis and reportedly has minimal other effects on zebrafish embryogenesis. We found that 0.003% PTU altered retinoic acid and insulin-like growth factor (IGF regulation of neural crest and mesodermal components of craniofacial development. Reduction of retinoic acid synthesis by the pan-aldehyde dehydrogenase inhibitor diethylbenzaldehyde, only when combined with 0.003% PTU, resulted in extraocular muscle disorganization. PTU also decreased retinoic acid-induced teratogenic effects on pharyngeal arch and jaw cartilage despite morphologically normal appearing PTU-treated controls. Furthermore, 0.003% PTU in combination with inhibition of IGF signaling through either morpholino knockdown or pharmacologic inhibition of tyrosine kinase receptor phosphorylation, disrupted jaw development and extraocular muscle organization. PTU in and of itself inhibited neural crest development at higher concentrations (0.03% and had the greatest inhibitory effect when added prior to 22 hours post fertilization (hpf. Addition of 0.003% PTU between 4 and 20 hpf decreased thyroxine (T4 in thyroid follicles in the nasopharynx of 96 hpf embryos. Treatment with exogenous triiodothyronine (T3 and T4 improved, but did not completely rescue, PTU-induced neural crest defects. Thus, PTU should be used with caution when studying zebrafish embryogenesis as it alters the threshold of different signaling pathways important during craniofacial development. The effects of PTU on neural crest development are partially caused by thyroid hormone signaling.

  7. Phenothiourea sensitizes zebrafish cranial neural crest and extraocular muscle development to changes in retinoic acid and IGF signaling.

    Science.gov (United States)

    Bohnsack, Brenda L; Gallina, Donika; Kahana, Alon

    2011-01-01

    1-Phenyl 2-thiourea (PTU) is a tyrosinase inhibitor commonly used to block pigmentation and aid visualization of zebrafish development. At the standard concentration of 0.003% (200 µM), PTU inhibits melanogenesis and reportedly has minimal other effects on zebrafish embryogenesis. We found that 0.003% PTU altered retinoic acid and insulin-like growth factor (IGF) regulation of neural crest and mesodermal components of craniofacial development. Reduction of retinoic acid synthesis by the pan-aldehyde dehydrogenase inhibitor diethylbenzaldehyde, only when combined with 0.003% PTU, resulted in extraocular muscle disorganization. PTU also decreased retinoic acid-induced teratogenic effects on pharyngeal arch and jaw cartilage despite morphologically normal appearing PTU-treated controls. Furthermore, 0.003% PTU in combination with inhibition of IGF signaling through either morpholino knockdown or pharmacologic inhibition of tyrosine kinase receptor phosphorylation, disrupted jaw development and extraocular muscle organization. PTU in and of itself inhibited neural crest development at higher concentrations (0.03%) and had the greatest inhibitory effect when added prior to 22 hours post fertilization (hpf). Addition of 0.003% PTU between 4 and 20 hpf decreased thyroxine (T4) in thyroid follicles in the nasopharynx of 96 hpf embryos. Treatment with exogenous triiodothyronine (T3) and T4 improved, but did not completely rescue, PTU-induced neural crest defects. Thus, PTU should be used with caution when studying zebrafish embryogenesis as it alters the threshold of different signaling pathways important during craniofacial development. The effects of PTU on neural crest development are partially caused by thyroid hormone signaling.

  8. Retinoic acid regulates CD1d gene expression at the transcriptional level in human and rodent monocytic cells.

    Science.gov (United States)

    Chen, Qiuyan; Ross, A Catharine

    2007-04-01

    CD1d belongs to a group of nonclassical antigen-presenting molecules that present glycolipid antigens and thereby activate natural killer T (NKT) cells, a subset of bifunctional T cells. Little is known so far regarding the expression and physiologic regulation of CD1d. Here we show that all-trans-retinoic acid (RA), the active metabolite of vitamin A, rapidly (1 hr after treatment) increases CD1d mRNA in human and rodent monocytic cells at a physiologic dose (10 nM). The induction is RA specific and RA receptor (RAR) dependent-RA and an RARalpha agonist, Am580, both had a pronounced positive effect, whereas the addition of RARalpha antagonist partially blocked the increase in CD1d mRNA induced by RA and Am580. The induction was also completely blocked by the presence of actinomycin D. A putative RA-response element was identified in the distal 5' flanking region of the CD1d gene, which binds nuclear retinoid receptors and was responsive to RA in both gel mobility shift assay and transient transfection assay in THP-1 cells. These results further confirmed the transcriptional regulation of RA in CD1d gene expression. Moreover, RA significantly increased alpha-galactosylceramide-induced spleen cell proliferation. These studies together provide evidence for a previously unknown mechanism of CD1d gene expression regulation by RA and suggest that RA is a significant modulator of NKT cell activation.

  9. In vitro induction and differentiation of umbilical cord mesenchymal stem cells into neuron-like cells by alltrans retinoic acid

    Institute of Scientific and Technical Information of China (English)

    Wei; Jin; Yao-Peng; Xu; An-Huai; Yang; Yi-Qiao; Xing

    2015-01-01

    AIM: To determine the optimal concentration for inducing the differentiation of human umbilical cord-derived mesenchymal stem cells(h UC-MSCs) into neuron-like cells, although it is understood that all-trans retinoic acid(ATRA) regulates cell proliferation in the nervous system by modulating the balance between mitosis and apoptosis.METHODS: The abilities of ATRA to promote apoptosis as well as neural differentiation were assessed in cultured h UC-MSCs by morphological observation, MTT assay, annexin V-FITC/PI flow cytometry and immunocytochemistry.RESULTS: The data showed that low concentrations of ATRA(0.5 μmol, 0.25 μmol) had no effect on the number of cells. However, treatment with 1.0 μmol or 2.0 μmol ATRA induced a 24.16% and 52.67% reduction in cell number, respectively, compared with vehicle-treated cultures. Further, 4.0 μmol ATRA had a potent effect on cell number, with almost no adherent cells recovered after 24 h. We further showed that 0.5 μmol ATRA caused these cells to express characteristic markers of neuronal progenitor cells.CONCLUSION: Taken together, we conclude that ATRA has a dose-dependent influence on the neural differentiation and apoptosis of h UC-MSCs. These findings have implications on the use of ATRA-differentiated h UC-MSCs for the study of neural degeneration diseases.

  10. THE EFFECTS OF RETINOIC ACID ON EXPRESSION OF C-MYC, C-FOS IN LEUKEMIC PROMYELOCYTES

    Institute of Scientific and Technical Information of China (English)

    邵国英; 徐荣婷; 孙关林; 欧阳仁荣; 应大明

    1992-01-01

    The expression of c-myc, c-fos of leukemic promyelocytes (HL-60 and acute promyelocytic leukemia cells) from 18 acute promyelocytic leukemia (APL) patients treated with all-trans retinoic acid (RA) in vitro was studied. There was no expression of c-fos in HL-60 cells and APL cells from 17 patients. But in one case, a slight expression of c-fos in leukemic cells was observed, and the alteration of expression level was found during the treatment of the cells with RA in vitro. The expression of c-myc in HL-60 cells induced by RA was altered, decrease in the early, increase in the middle, and decline in the later stage were found. The c-myc expression in leukemic cells of eighteen APL patients was variable. There was c-myc expression in eleven APL cells, but no expression in the others. The APL cells with c-myc expression were treated with RA in vitro to observe the kinetic changes of c-myc RNA level. The results showed that the expression of c-myc was gradually decreased except in few cases. Using in situ hybridization technique for detecting the alteration of c-myc expression in leukemic cells of two APL patients. the high level of c-myc before RA treatment and low level of c-myc expression after obtaining complete remission induced by RA were found. The possibility of different proto-oncogenes implicated differentiation was discussed.

  11. Retinoic Acid Receptors Control Spermatogonia Cell-Fate and Induce Expression of the SALL4A Transcription Factor.

    Directory of Open Access Journals (Sweden)

    Aurore Gely-Pernot

    2015-10-01

    Full Text Available All-trans retinoic acid (ATRA is instrumental to male germ cell differentiation, but its mechanism of action remains elusive. To address this question, we have analyzed the phenotypes of mice lacking, in spermatogonia, all rexinoid receptors (RXRA, RXRB and RXRG or all ATRA receptors (RARA, RARB and RARG. We demonstrate that the combined ablation of RXRA and RXRB in spermatogonia recapitulates the set of defects observed both upon ablation of RAR in spermatogonia. We also show that ATRA activates RAR and RXR bound to a conserved regulatory region to increase expression of the SALL4A transcription factor in spermatogonia. Our results reveal that this major pluripotency gene is a target of ATRA signaling and that RAR/RXR heterodimers are the functional units driving its expression in spermatogonia. They add to the mechanisms through which ATRA promote expression of the KIT tyrosine kinase receptor to trigger a critical step in spermatogonia differentiation. Importantly, they indicate also that meiosis eventually occurs in the absence of a RAR/RXR pathway within germ cells and suggest that instructing this process is either ATRA-independent or requires an ATRA signal originating from Sertoli cells.

  12. Initiating meiosis: the case for retinoic acid.

    Science.gov (United States)

    Griswold, Michael D; Hogarth, Cathryn A; Bowles, Josephine; Koopman, Peter

    2012-02-01

    The requirement for vitamin A in reproduction and development was first determined from studies of nutritional deficiencies. Subsequent research has shown that embryonic development and both male and female reproduction are modulated by retinoic acid (RA), the active form of vitamin A. Because RA is active in multiple developmental systems, its synthesis, transport, and degradation are tightly regulated in different tissues. A growing body of evidence implicates RA as a requirement for the initiation of meiosis in both male and female mammals, resulting in a mechanistic model involving the interplay of RA, RA synthesis enzymes, RA receptors, and degradative cytochrome P450 enzymes in this system. Recently, that model has been challenged, prompting a review of the established paradigm. While it remains possible that additional molecules may be involved in regulating entry into meiosis, the weight of evidence supporting a key role for RA is incontrovertible.

  13. Role of retinoic receptors in lung carcinogenesis

    Directory of Open Access Journals (Sweden)

    Renyi-Vamos Ferenc

    2008-07-01

    Full Text Available Abstract Several in vitro and in vivo studies have examined the positive and negative effects of retinoids (vitamin A analogs in premalignant and malignant lesions. Retinoids have been used as chemopreventive and anticancer agents because of their pleiotropic regulator function in cell differentiation, growth, proliferation and apoptosis through interaction with two types of nuclear receptors: retinoic acid receptors and retinoid X receptors. Recent investigations have gradually elucidated the function of retinoids and their signaling pathways and may explain the failure of earlier chemopreventive studies. In this review we have compiled basic and recent knowledge regarding the role of retinoid receptors in lung carcinogenesis. Sensitive and appropriate biological tools are necessary for screening the risk population and monitoring the efficacy of chemoprevention. Investigation of retinoid receptors is important and may contribute to the establishment of new strategies in chemoprevention for high-risk patients and in the treatment of lung cancer.

  14. Hypochlorous and peracetic acid induced oxidation of dairy proteins.

    Science.gov (United States)

    Kerkaert, Barbara; Mestdagh, Frédéric; Cucu, Tatiana; Aedo, Philip Roger; Ling, Shen Yan; De Meulenaer, Bruno

    2011-02-09

    Hypochlorous and peracetic acids, both known disinfectants in the food industry, were compared for their oxidative capacity toward dairy proteins. Whey proteins and caseins were oxidized under well controlled conditions at pH 8 as a function of the sanitizing concentration. Different markers for protein oxidation were monitored. The results established that the protein carbonyl content was a rather unspecific marker for protein oxidation, which did not allow one to differentiate the oxidant used especially at the lower concentrations. Cysteine, tryptophan, and methionine were proven to be the most vulnerable amino acids for degradation upon hypochlorous and peracetic acid treatment, while tyrosine was only prone to degradation in the presence of hypochlorous acid. Hypochlorous acid induced oxidation gave rise to protein aggregation, while during peracetic acid induced oxidation, no high molecular weight aggregates were observed. Protein aggregation upon hypochlorous acid oxidation could primarily be linked to tryptophan and tyrosine degradation.

  15. An optimized and validated RP-HPLC/UV detection method for simultaneous determination of all-trans-retinol (vitamin A) and alpha-tocopherol (vitamin E) in human serum: comparison of different particulate reversed-phase HPLC columns.

    Science.gov (United States)

    Khan, Abad; Khan, Muhammad I; Iqbal, Zafar; Shah, Yasar; Ahmad, Lateef; Watson, David G

    2010-09-01

    A novel, simple and fast reversed-phase HPLC/UV method was developed, optimized for various chromatographic conditions, and validated according to international guidelines for simultaneous determination of all-trans-retinol and alpha-tocopherol in human serum using retinyl acetate as internal standard in the concentration of 0.5 microg/ml. A liquid-phase extraction was applied to the 250 microl of serum with n-hexane-dichloromethane mixture (70:30, v/v), in two steps, using ethanol-methanol mixture (95:5, v/v) for protein precipitation and BHT (butylated hydroxy toluene) as stabilizer for sample preparation. Both analytes were analyzed on Kromasil 100 C(18) column (150 mm x 4.6 mm, 5 microm), Brownlee analytical (Perkin Elmer) C(18) column (150 mm x 4.6 mm, 5 microm), and Supelco (Supelcosil) LC-18 column (150 mm x 3 mm, 3 microm), protected by a Perkin Elmer C(18) (30 mm x 4.6 mm, 10 microm; Norwalk, USA) pre-column guard cartridge, at 292 nm wavelength, using methanol-water (99:1, v/v), in isocratic mode as mobile phase applied at flow rate of 1.5 ml/min and 1 ml/min for both 5 microm and 3 microm columns, respectively. Complete separation of all the analytes was achieved in 3 and 6 min on 3 microm and 5 microm columns, respectively by injecting 20 microl of sample into the HPLC system by autosampler, keeping column oven temperature at 25 degrees C. Different particulate reversed-phase chromatographic columns were evaluated in order to select the best column in terms of sensitivity, selectivity, resolution and short run time of both the analytes and it was concluded that 3 microm columns are better to be used in clinical set up as well as in laboratories for the separation of these analytes in a shorter time as compared with 5 microm columns. The method was validated and applied for the analysis of all-trans-retinol and alpha-tocopherol in the serum of human volunteers.

  16. The effect pathway of retinoic acid through regulation of retinoic acid receptor in gastric cancer cells

    Institute of Scientific and Technical Information of China (English)

    Su Liu; Qiao Wu; Zheng-Ming Chen; Wen-Jin Su

    2001-01-01

    AIM To evaluate the role of RARa gene in mediating the growth inhibitory effect of ail-trans retinoic acid (ATRA)on gastric cancer cells.``METHODS The expression levels of retinoic acid receptors (RARs) in gastric cancer cells were detected by Northern blot. Transient transfection and chlorophenicol acetyl transferase (CAT) assay were used to show the transcriptional activity of β retinoic acid response element (βRARE) and AP-l activity. Cell growth inhibition was determined by MTT assay and anchorage-independent growth assay, respectively. Stable transfection was performed by the method of Lipofectamine, and the cells were screened by G418.``RESULTS ATRA could induce expression level of RARα in MGC80-3, BGCC8823 and SGC-7901 cells obviously,resulting in growth inhibition of these cell lines. After sense RARa gene was transfected into MKN-45 cells that expressed rather Iow level of RARα and could not be induced by ATRA, the cell growth was inhibited by ATRA markedly. In contrast, when antisense RARα gene was transfected into BGC-825 cells, a little inhibitory effect by ATRA was seen, compared with the parallel BGC-823cells. In transient transfection assay, ATRA effectively induced transcriptional activity of βRARE in MGC80-3,BGC.823, SGC-7902 and MKN/RARa cell lines, but not in MKN-45 and BGC/aRARa cell lines. Similar results were observed in measuring anti-AP-l activity by ATRA in these cancer cell lines.``CONCLUSION ATRA inhibits the growth of gastric cancer cells by up-regulating the level of RARa; RARa is the major mediator of ATRA action in gastric cancer cells; and adequate level of RAPa is required for ATRA effect on gastric cancer cells.``

  17. Pseudotumor cerebri presenting with visual failure in promyelocytic leukemia: a case report

    Directory of Open Access Journals (Sweden)

    Rasul Fahid T

    2012-11-01

    Full Text Available Abstract Introduction Pseudotumor cerebri secondary to all-trans retinoic acid in acute promyelocytic leukemia is a reported but rare complication of the therapy. Most cases improve following the discontinuation of all-trans retinoic acid. There is no published literature on how to manage such patients if severe symptoms of increased intracranial pressure continue after discontinuation of the drug. Case presentation We report the case of a 16-year-old Afro-Caribbean woman with aggressive secondary pseudotumor cerebri who presented to our facility with visual failure that persisted despite discontinuation of all-trans retinoic acid. A lumbar drain was inserted for 11 days resulting in symptomatic relief of headaches and objective improvement of visual failure. Pressure settings were titrated regularly to ensure optimal symptomatic relief. Conclusions The use of a lumbar drain for continuous drainage of cerebrospinal fluid in patients with all-trans retinoic acid-induced pseudotumor cerebri resistant to all-trans retinoic acid discontinuation is a feasible management option. This method can be used when other less invasive measures have failed to improve signs and symptoms. Permanent drainage of cerebrospinal fluid with a shunt may also provide a long-term viable management strategy but the use of a lumbar drain may be preferable if the cause of pseudotumor cerebri is known to be self-limiting.

  18. Transvitreal retino-choroidal biopsy of suspected malignant lesions of the choroid

    DEFF Research Database (Denmark)

    Jensen, O.A.; Prause, J.U.; Scherfig, E.

    1997-01-01

    ophthalmology, intraocular biopsy, transvitreal retino-choroidal biopsy, malignant melanoma of choroid, histopathology, brachytherapy......ophthalmology, intraocular biopsy, transvitreal retino-choroidal biopsy, malignant melanoma of choroid, histopathology, brachytherapy...

  19. Retinoic acid signaling in axonal regeneration

    Directory of Open Access Journals (Sweden)

    Radhika ePuttagunta

    2012-01-01

    Full Text Available Following an acute central nervous system injury, axonal regeneration and functional recovery are extremely limited. This is due to an extrinsic inhibitory growth environment and the lack of intrinsic growth competence. Retinoic acid (RA signaling, essential in developmental dorsoventral patterning and specification of spinal motor neurons, has been shown through its receptor, the transcription factor RA receptor β2 (RARß2, to induce axonal regeneration following spinal cord injury (SCI. Recently, it has been shown that in dorsal root ganglia neurons, cAMP levels were greatly increased by lentiviral RARβ2 expression and contributed to neurite outgrowth. Moreover, RARβ agonists, in cerebellar granule neurons and in the brain in vivo, induced phosphoinositide 3-kinase dependent phosphorylation of AKT that was involved in RARβ-dependent neurite outgrowth. More recently, RA-RARß pathways were shown to directly transcriptionally repress a member of the inhibitory Nogo receptor complex, Lingo-1, under an axonal growth inhibitory environment in vitro as well as following spinal injury in vivo. This perspective focuses on these newly discovered molecular mechanisms and future directions in the field.

  20. Canonical Coordinates for Retino-Cortical Magnification

    Directory of Open Access Journals (Sweden)

    Luc Florack

    2014-02-01

    Full Text Available A geometric model for a biologically-inspired visual front-end is proposed, based on an isotropic, scale-invariant two-form field. The model incorporates a foveal property typical of biological visual systems, with an approximately linear decrease of resolution as a function of eccentricity, and by a physical size constant that measures the radius of the geometric foveola, the central region characterized by maximal resolving power. It admits a description in singularity-free canonical coordinates generalizing the familiar log-polar coordinates and reducing to these in the asymptotic case of negligibly-sized geometric foveola or, equivalently, at peripheral locations in the visual field. It has predictive power to the extent that quantitative geometric relationships pertaining to retino-cortical magnification along the primary visual pathway, such as receptive field size distribution and spatial arrangement in retina and striate cortex, can be deduced in a principled manner. The biological plausibility of the model is demonstrated by comparison with known facts of human vision.

  1. New discovery of cryptorchidism: Decreased retinoic acid in testicle.

    Science.gov (United States)

    Peng, Jinpu; Shen, Lianju; Chen, Jinjun; Cao, Xining; Zhou, Yue; Weng, Huali; Long, Chunlan; Zhang, Deying; Tu, Shengfen; Zhang, Yan; He, Dawei; Lin, Tao; Wei, Guanghui

    2016-05-01

    This study focuses on investigation of cryptorchidism induced by flutamide (Flu) and its histopathological damage, and detects retinoic acid concentration in testicle tissue, in order to find a new method for clinical treatment to infertility caused by cryptorchidism. Twenty SD (Sprague Dawley) pregnant rats were randomly divided into Flu cryptorchidism group (n = 10) and normal control group (n = 10). HE stained for observing morphological difference. Transmission electron microscope (TEM) was used for observing the tight junction structure between Sertoli cells. Epididymal caudal sperms were counted and observed in morphology. The expression of stimulated by retinoic acid gene 8 (Stra8) was detected using immunohistochemistry, western blot, and Q-PCR. High performance liquid chromatography (HPLC) analysis was made on retinoic acid content. Sperm count and morphology observation confirmed cryptorchidism group was lower than normal group in sperm quantity and quality. The observation by TEM showed a loose structure of tight junctions between Sertoli cells. Immunohistochemistry, western blot, and Q-PCR showed that cryptorchidism group was significantly lower than normal group in the expression of Stra8. HPLC showed that retinoic acid content was significantly lower in cryptorchid testis than in normal testis. In the cryptorchidism model, retinoic acid content in testicular tissue has a significant reduction; testicles have significant pathological changes; damage exists in the structure of tight junctions between Sertoli cells; Stra8 expression has a significant reduction, perhaps mainly contributing to spermatogenesis disorder.

  2. New discovery of cryptorchidism: Decreased retinoic acid in testicle

    Directory of Open Access Journals (Sweden)

    Jinpu Peng

    2016-05-01

    Full Text Available This study focuses on investigation of cryptorchidism induced by flutamide (Flu and its histopathological damage, and detects retinoic acid concentration in testicle tissue, in order to find a new method for clinical treatment to infertility caused by cryptorchidism. Twenty SD (Sprague Dawley pregnant rats were randomly divided into Flu cryptorchidism group (n = 10 and normal control group (n = 10. HE stained for observing morphological difference. Transmission electron microscope (TEM was used for observing the tight junction structure between Sertoli cells. Epididymal caudal sperms were counted and observed in morphology. The expression of stimulated by retinoic acid gene 8 (Stra8 was detected using immunohistochemistry, western blot, and Q-PCR. High performance liquid chromatography (HPLC analysis was made on retinoic acid content. Sperm count and morphology observation confirmed cryptorchidism group was lower than normal group in sperm quantity and quality. The observation by TEM showed a loose structure of tight junctions between Sertoli cells. Immunohistochemistry, western blot, and Q-PCR showed that cryptorchidism group was significantly lower than normal group in the expression of Stra8. HPLC showed that retinoic acid content was significantly lower in cryptorchid testis than in normal testis. In the cryptorchidism model, retinoic acid content in testicular tissue has a significant reduction; testicles have significant pathological changes; damage exists in the structure of tight junctions between Sertoli cells; Stra8 expression has a significant reduction, perhaps mainly contributing to spermatogenesis disorder.

  3. Valproic acid-induced hyperammonaemic coma and unrecognised portosystemic shunt.

    Science.gov (United States)

    Nzwalo, Hipólito; Carrapatoso, Leonor; Ferreira, Fátima; Basilio, Carlos

    2013-06-01

    Hyperammonaemic encephalopathy is a rare and potentially fatal complication of valproic acid treatment. The clinical presentation of hyperammonaemic encephalopathy is wide and includes seizures and coma. We present a case of hyperammonaemic coma precipitated by sodium valproate use for symptomatic epilepsy in a patient with unrecognised portosystemic shunt, secondary to earlier alcoholism. The absence of any stigmata of chronic liver disease and laboratory markers of liver dysfunction delayed the recognition of this alcohol-related complication. The portal vein bypass led to a refractory, valproic acid-induced hyperammonaemic coma. The patient fully recovered after dialysis treatment.

  4. Amoxicillin/clavulanic acid-induced pemphigus vulgaris: case report.

    Science.gov (United States)

    Baroni, Adone; Russo, Teresa; Faccenda, Franco; Piccolo, Vincenzo

    2012-01-01

    Drug-induced pemphigus is a well-established variety of pemphigus, presenting with clinical and histopathologic features identical to idiopathic form. Medical history plays a fundamental role in the diagnosis of drug-induced pemphigus. A large variety of drugs have been implicated in its pathogenesis and they may induce acantholysis via biochemical and/or immune mechanism. We present a case of a 69-year-old woman affected by amoxicillin/clavulanic acid-induced pemphigus and discuss its pathogenetic mechanism.

  5. Protective effect of all-trans retinoic acid pretreatment against rat intestinal injury induced by hepatic inflow occlusion%全反式维甲酸预处理对肝血流阻断大鼠肠道的保护作用

    Institute of Scientific and Technical Information of China (English)

    王钟兴; 黄婵燕; 方佳峰; 陈图锋

    2013-01-01

    目的:探讨全反式维甲酸(ATRA)对肝血流阻断所致肠道损伤的影响和机制.方法:32只雄性SD大鼠,随机分为4组:假手术(sham)组、肝血流阻断(HIO)组、溶媒对照(DMSO+ HIO)组和ATRA预处理(ATRA+ HIO)组.ATRA预处理组以ATRA 15 mg·kg-1·d-1灌胃,溶媒对照组以等体积二甲基亚砜(DMSO)灌胃,共10 d.Pringl'e,s法建立肝血流阻断模型,持续30 min,解除阻断再灌注2h后,采集各组大鼠末端回肠和血清.光镜下观察回肠病理改变、行肠黏膜组织Chiu氏评分;比色法检测血清二胺氧化酶(DAO)水平、回肠组织丙二醛(MDA)含量和超氧化物歧化酶(SOD)活性;ELISA法测定血清白细胞介素(IL)-1β及肿瘤坏死因子(TNF)-α水平;Western blotting检测组织中胞浆锰超氧化物歧化酶(MnSOD)和胞核NF-κB p65蛋白的表达量.结果:相对于HIO组和DMSO+ HIO组,ATRA能缓解肝血流阻断后肠黏膜组织病理损伤,降低Chiu氏评分和血清DAO水平(P<0.05),减少回肠组织中MDA含量(P<0.05),提高SOD活性(P<0.05),增加组织MnSOD的表达(P<0.05),减少胞核NF-κB p65蛋白含量(P<0.05),降低血清IL-1β和TNF-α水平(P<0.05).结论:ATRA通过增加组织抗氧化能力,抑制NF-κB通路的激活,减少促炎因子的产生,从而减轻大鼠肝血流阻断造成的肠道损伤.

  6. The effect of all-trans retinoic acid at varying dose in the treatment of DSS-induced colitis in mice%不同剂量全反式维甲酸对DSS诱导小鼠肠炎的治疗作用

    Institute of Scientific and Technical Information of China (English)

    冯锦山; 邓颖; 杨正; 叶石才; 朱宇珍; 叶营

    2016-01-01

    目的 探讨不同剂量全反式维甲酸(AtRA)对葡聚糖硫酸钠(DSS)诱导结肠炎小鼠的治疗作用.方法 实验小鼠随机分为四组:对照组(Control组),模型组(DSS组),低剂量AtRA(DSS+AtRA-L)组,高剂量AtRA(DSS+AtRA-H)组,每组8只.除Control组外,其他组小鼠自由饮用3%DSS溶液7d诱导结肠炎.DSS+AtRA-L组和DSS+AtRA-H组分别给予AtRA 15 mg/kg和30 mg/kg腹腔注射8~14d.每天记录小鼠改良疾病活动指数(mDAI).第15天处死小鼠,测定各组小鼠结肠长度、结肠组织学评分、血清及结肠组织TNF-α水平.结果DSS+AtRA-H和DSS+AtRA-L组的mDAI和结肠组织学评分较DSS组降低,结肠长度则较DSS组增加,差异均有统计学意义(P<0.01或0.05).DSS+AtRA-H组和DSS+AtRA-L组的黏膜结构改善不明显,其结肠组织学评分高于Control组(P<0.01).DSS+AtRA-H组和DSS+AtRA-L组的TNF-α免疫组化评分比DSS组显著降低(P<0.01),DSS+AtRA-L组高于Control组(P<0.01),但DSS+AtRA-H组与Control组差异无统计学意义(P>0.05).DSS+AtRA-H组和DSS+AtRA-L组的血清TNF-α水平均比DSS组降低(P<0.01),但仍高于Control组(P<0.01).结论AtRA对DSS诱导的小鼠结肠炎有疗效,治疗作用呈剂量依赖关系,但其在肠黏膜结构和结肠缩短方面存在不同程度的局限性.

  7. Clinical observation of the combination of all-trans retinoic acid and arsenic trioxide for the treatment of acute promyelicy leukemia%全反式维甲酸联合三氧化二砷治疗急性早幼粒细胞白血病临床观察

    Institute of Scientific and Technical Information of China (English)

    晋红丽; 韩艳玲; 孙静; 王国江; 史长山

    2009-01-01

    目的 探讨全反式维甲酸(ATRA)联合三氧化二砷(As2O3)治疗初治急性早幼粒细胞自血病(APL)的疗效和不良反应.方法 初治APL14例均接受ATRA联合As2O3方案治疗,ATPA 25 mg/m2/d,分2~3次口服;As2O310 mg/m2/d加入5%葡萄糖500 ml静脉滴注持续3~4 h,1次/d,观察CR率,CR时间以及不良反应.结果 14例患者完全缓解(CR)13例,死亡1例,CR率92.9%,达CR时26~45 d,平均30.1 d.结论 ATRA联合As2O3治疗初治APL疗效好,不良反应少,能缩短达CR的时间.

  8. 维甲酸对HeLa细胞间隙连接蛋白基因cx43表达的调节作用%The regulation effect of all-trans-retinoic acid on expression of connexin gene cx43 in HeLa

    Institute of Scientific and Technical Information of China (English)

    陈必良; 马向东; 王德堂; 辛晓燕

    1999-01-01

    目的:探讨分化诱导剂维甲酸对肿瘤抑制基因--细胞间隙连接蛋白基因cx43在人子宫颈癌细胞系HeLa中表达的调节作用.方法:应用核酸原位杂交、流式细胞仪、Westen blot及Lucifer Yellow划痕标记荧光传输技术,研究维甲酸作用对HeLa细胞cx43 mRNA及其蛋白表达,以及对HeLa细胞生长和通讯功能的调节作用.结果:HeLa细胞经维甲酸处理后,原位杂交显示,HeLa细胞cx43 mRNA水平上调;流式细胞仪分析,Cx43蛋白荧光强度增强,阳性细胞计数率由1.9%上升至26.3%;Wester blot检测到分子量约43KDa的Cx43蛋白表达;HeLa细胞生长明显受抑;细胞间隙连接通讯功能有所恢复.结论:维甲酸可通过上调肿瘤抑制基因cx43及其蛋白在HeLa细胞中的表达,实现对宫颈癌细胞恶性表型的逆转作用,这可能是维甲酸肿瘤抑制作用的重要机制之一.

  9. Multiple cytochrome P-450 genes are concomitantly regulated by vitamin A under steady-state conditions and by retinoic acid during hepatic first-pass metabolism.

    Science.gov (United States)

    Ross, A Catharine; Cifelli, Christopher J; Zolfaghari, Reza; Li, Nan-Qian

    2011-01-01

    Vitamin A (retinol) is an essential precursor for the production of retinoic acid (RA), which in turn is a major regulator of gene expression, affecting cell differentiation throughout the body. Understanding how vitamin A nutritional status, as well as therapeutic retinoid treatment, regulates the expression of retinoid homeostatic genes is important for improvement of dietary recommendations and therapeutic strategies using retinoids. This study investigated genes central to processes of retinoid uptake and storage, release to plasma, and oxidation in the liver of rats under steady-state conditions after different exposures to dietary vitamin A (deficient, marginal, adequate, and supplemented) and acutely after administration of a therapeutic dose of all-trans-RA. Over a very wide range of dietary vitamin A, lecithin:retinol acyltransferase (LRAT) as well as multiple cytochrome P-450s (CYP26A1, CYP26B1, and CYP2C22) differed by diet and were highly correlated with one another and with vitamin A status assessed by liver retinol concentration (all correlations, P < 0.05). After acute treatment with RA, the same genes were rapidly and concomitantly induced, preceding retinoic acid receptor (RAR)β, a classical direct target of RA. CYP26A1 mRNA exhibited the greatest dynamic range (change of log 2(6) in 3 h). Moreover, CYP26A1 increased more rapidly in the liver of RA-primed rats than naive rats, evidenced by increased CYP26A1 gene expression and increased conversion of [(3)H]RA to polar metabolites. By in situ hybridization, CYP26A1 mRNA was strongly regulated within hepatocytes, closely resembling retinol-binding protein (RBP)4 in location. Overall, whether RA is produced endogenously from retinol or administered exogenously, changes in retinoid homeostatic gene expression simultaneously favor both retinol esterification and RA oxidation, with CYP26A1 exhibiting the greatest dynamic change.

  10. Role of JWA in acute promyelocytic leukemia cell differentiation and apoptosis triggered by retinoic acid, 12-tetradecanoylphorbol-13-acetate and arsenic trioxide

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    JWA, a cytoskeleton associated gene, was primarily found to be regulated by all trans-retinoic acid (ATRA), 13 cis-retinoic acid (13 cis-RA) and 12-tetradecano- ylphorbol-13-acetate (TPA). Our previous data showed that JWA might be involved in both cellular differentiation and apoptosis induced by several chemicals. In this study, we addressed the possible mechanism of JWA in the regulation of cell differentiation and apoptosis in NB4, a human acute promyelocytic leukemia cell line. CD11b/CD33 expression and cell cycle were analyzed for detecting of cell differentiation and apoptosis. Both reverse-transcription polymerase chain reaction (RT-PCR) and Western blot assays were used for understanding the expressions of JWA. The results showed that under the indicated concentrations ATRA (10?6 mol/L) and As2O3 (10?6 mol/L) induced cell differentiation and apoptosis separately; while both 4HPR (10?6 mol/L) and TPA (10?7 mol/L) showed dual-directional effects on NB4 cells, they not only trigger cells' differentiation but also induce cells apoptosis at the same time. All chemicals up-regulated JWA expression whatever they trigger cells either differentiation or apoptosis; however, it seems that the chemicals have no effect on PML/RAR? in the treated NB4 cells. Anti-sense JWA oligonucleotide could partially block the ability of TPA in inducing cell differentiation and apoptosis via direct signal pathway. Interestingly, a high molecular weight JWA protein (JWAF) was identified only in de novo primary APL cells and it was also responsible for ATRA treatment. It raises questions of whether the JWAF is a novel APL specific marker and, how it was involved in the known mechanism of APL.

  11. The synthetic retinoid AGN 193109 but not retinoic acid elevates CYP1A1 levels in mouse embryos and Hepa-1c1c7 cells.

    Science.gov (United States)

    Soprano, D R; Gambone, C J; Sheikh, S N; Gabriel, J L; Chandraratna, R A; Soprano, K J; Kochhar, D M

    2001-07-15

    The synthetic retinoid AGN 193109 is a potent pan retinoic acid receptor (RAR) antagonist. Treatment of pregnant mice with a single oral 1 mg/kg dose of this antagonist on day 8 postcoitum results in severe craniofacial (median cleft face or frontonasal deficiency) and eye malformations in virtually all exposed fetuses. Using differential display analysis, we have determined that CYP1A1 mRNA levels are elevated in mouse embryos 6 h following treatment with AGN 193109. Similarly, an elevation in CYP1A1 mRNA levels, protein levels, and aryl hydrocarbon hydoxylase activity occurs in Hepa-1c1c7 cells, with the maximal elevation observed when the cells were treated with 10(-5) M AGN 193109 for 4 to 8 h. Elevation in CYP1A1 mRNA levels in mouse embryos and Hepa-1c1c7 cells does not occur upon treatment with the natural retinoid, all-trans-retinoic acid. Finally, elevation in CYP1A1 mRNA levels was not observed when mutant Hepa-1c1c7 cells, which are defective in either the aryl hydrocarbon receptor (AhR) or aryl hydrocarbon receptor nuclear translocator (ARNT), were treated with AGN 193109. This suggests that the AhR/ARNT pathway and not the RAR/RXR pathway is mediating the elevation of CYP1A1 mRNA levels by AGN 193109, at least in the Hepa-1c1c7 cells. This is the first example of a retinoid that displays the abililty to regulate both the RAR/RXR and AhR/ARNT transcriptional regulatory pathways.

  12. Retinoic acid exerts dual regulatory actions on the expression and nuclear localization of interferon regulatory factor-1.

    Science.gov (United States)

    Luo, Xin M; Ross, A Catharine

    2006-05-01

    Interferon regulatory factor-1 (IRF-1), a transcription factor and tumor suppressor involved in cell growth regulation and immune responses, has been shown to be induced by all-trans retinoic acid (ATRA). However, the factors controlling the cellular location and activity of IRF-1 are not well understood. In this study, we examined the expression of IRF-1 and its nuclear localization, DNA-binding activity, and target gene expression in human mammary epithelial MCF10A cells, a model of breast epithelial cell differentiation and carcinogenesis. Following initial treatment with ATRA, IRF-1 mRNA and protein were induced within 2 hrs, reached a peak (>30-fold induction) at 8 hrs, and declined afterwards. IRF-1 protein was predominantly cytoplasmic during this treatment. Although a second dose of ATRA or Am580 (a related retinoid selective for retinoic acid receptor-alpha [RARalpha]), given 16 hrs after the first dose, restimulated IRF-1 mRNA and protein levels to a similar level to that obtained by the first dose, IRF-1 was predominantly concentrated in the nucleus after restimulation. ATRA and Am580 also increased nuclear RARalpha, whereas retinoid X receptor-alpha (RXRalpha)--a dimerization partner for RARalpha, was localized to the nucleus upon second exposure to ATRA. However, ATRA and Am580 did not regulate the expression or activation of signal transducer and activator of transcription-1 (STAT-1), a transcription factor capable of inducing the expression of IRF-1, indicating an STAT-1-independent mechanism of regulation by ATRA and Am580. The increase in nuclear IRF-1 after retinoid restimulation was accompanied by enhanced binding to an IRF-E DNA response element, and elevated expression of an IRF-1 target gene, 2',5'-oligoadenylate synthetase-2. The dual effect of retinoids in increasing IRF-1 mRNA and protein and in augmenting the nuclear localization of IRF-1 protein may be essential for maximizing the tumor suppressor activity and the immunosurveillance

  13. [Sunitinib and zoledronic acid induced osteonecrosis of the jaw].

    Science.gov (United States)

    Soós, Balázs; Vajta, László; Szalma, József

    2015-11-15

    The tendency for bisphosphonate and non-bisphosphonate (eg.: antiresorptive or anti-angiogenesis drugs) induced osteonecrosis is increasing. Treatment of these patients is a challenge both for dentists and for oral and maxillofacial surgeons. Cooperation with the drug prescribing general medicine colleagues to prevent osteonecrosis is extremely important. Furthermore, prevention should include dental focus elimination, oral hygienic instructions and education, dental follow-up and, in case of manifest necrosis, referral to maxillofacial departments. Authors outline the difficulties of conservative and surgical treatment of a patient with sunitinib and zoledronic acid induced osteonecrosis. The patient became symptomless and the operated area healed entirely six and twelve months postoperatively. A long term success further follow-up is necessary to verify long-term success.

  14. Short communication: retinoic acid plus prolactin to synergistically increase specific casein gene expression in MAC-T cells.

    Science.gov (United States)

    Lee, H Y; Heo, Y T; Lee, S E; Hwang, K C; Lee, H G; Choi, S H; Kim, N H

    2013-06-01

    Mammary alveolar (MAC-T) cells, an established bovine mammary epithelial cell line, are frequently used to investigate differentiation. A lactogenic phenotype in these cells is induced by treatment with a combination of hydrocortisone, insulin, and prolactin (PRL). The effect of the vitamin A derivative retinoic acid (RA), which induces differentiation in many cells, has not been studied in MAC-T cells. The objective of this study was to evaluate the differentiation potential of RA (1 μM) in MAC-T cells and to examine the effect of combined treatment with RA (1 μM) and PRL (5 μg/mL). Although RA treatment alone inhibited MAC-T cell proliferation, co-treatment of RA with PRL increased cell growth compared with the control group (treated with 1 μg/mL hydrocortisone and 5 μg/mL insulin). The ratio of Bcl to Bax mRNA was decreased in the RA treatment compared with RA+PRL or control. Retinoic acid-induced differentiation of MAC-T cells was associated with an increase in the mRNA expression of αS1-casein (3.9-fold), αS2-casein (4.5-fold), and β-casein (4.4-fold) compared with the control group. Expression of αS1-casein, αS2-casein, and β-casein was increased 12.9-fold, 11.9-fold, and 19.3-fold, respectively, following treatment with RA and PRL combined compared with the control group. These results demonstrate that RA induces differentiation of MAC-T cells and acts synergistically with PRL to increase specific casein gene expression.

  15. High affinity retinoic acid receptor antagonists: analogs of AGN 193109.

    Science.gov (United States)

    Johnson, A T; Wang, L; Gillett, S J; Chandraratna, R A

    1999-02-22

    A series of high affinity retinoic acid receptor (RAR) antagonists were prepared based upon the known antagonist AGN 193109 (2). Introduction of various phenyl groups revealed a preference for substitution at the para-position relative to the meta-site. Antagonists with the highest affinities for the RARs possessed hydrophobic groups, however, the presence of polar functionality was also well tolerated.

  16. Induction of apoptosis and change of bcl—2 expression in macrophage Ana—1 cells by all—trans retinoic acid

    Institute of Scientific and Technical Information of China (English)

    YINDELING; XIUHAIREN; 等

    1996-01-01

    Macrophage cells play an important role in the initiation and regulation of the immune response.All-trans retinoic acid (ATRA) and its natural and synthetic analogs (retinoids)affect a large number of biological processes.Recently,retinoids have been shown promise in the therapy and prevention of various cancers.However,many interesting questions related to the activities of retinoids remain to be answered:(I) Molecular mechanisms by which retinoids exert their effects;(Ⅱ)why the clinical uses of retinoids give undesirable side effects of varying severity with a higher frequency of blood system symptoms;(Ⅲ)little is known for its impacts on macrophage cells etc.We set up this experiment,therefore,to examine the apoptosis of ATRA on macrophage Ana-1 cell line.Apoptosis of the cells was quantitated,after staining cells with propidium iodide(PI),by both accounting nuclear condensation and flow cytometry.When the cells were treated with ATRA at or higher than 1μM for more than 24h,significant amount of the apoptotic cells was observed.Induction of apoptosis of Ana-1 cells by ATRA was in time-and dose-dependent manners,exhibiting the similar pattern as the apoptosis induced by actinomycin D (ACTD).ATRA treatment of Ana-1 cells also caused the changes of the mRNA levels of apoptosis-associated gene bcl-2,as detected by Northern blot analysis.The temporal changes of bcl-2 expression by ATRA was also parallel to that by ACTD.In conclusion,ATRA can induce apoptosis in macrophage cells,which may be helpful in understanding of immunological functions retinoids.

  17. Impact of retinoic acid exposure on midfacial shape variation and manifestation of holoprosencephaly in Twsg1 mutant mice

    Directory of Open Access Journals (Sweden)

    Charles J. Billington

    2015-02-01

    Full Text Available Holoprosencephaly (HPE is a developmental anomaly characterized by inadequate or absent midline division of the embryonic forebrain and midline facial defects. It is believed that interactions between genes and the environment play a role in the widely variable penetrance and expressivity of HPE, although direct investigation of such effects has been limited. The goal of this study was to examine whether mice carrying a mutation in a gene encoding the bone morphogenetic protein (BMP antagonist twisted gastrulation (Twsg1, which is associated with a low penetrance of HPE, are sensitized to retinoic acid (RA teratogenesis. Pregnant Twsg1+/− dams were treated by gavage with a low dose of all-trans RA (3.75 mg/kg of body weight. Embryos were analyzed between embryonic day (E9.5 and E11.5 by microscopy and geometric morphometric analysis by micro-computed tomography. P19 embryonal carcinoma cells were used to examine potential mechanisms mediating the combined effects of increased BMP and retinoid signaling. Although only 7% of wild-type embryos exposed to RA showed overt HPE or neural tube defects (NTDs, 100% of Twsg1−/− mutants exposed to RA manifested severe HPE compared to 17% without RA. Remarkably, up to 30% of Twsg1+/− mutants also showed HPE (23% or NTDs (7%. The majority of shape variation among Twsg1+/− mutants was associated with narrowing of the midface. In P19 cells, RA induced the expression of Bmp2, acted in concert with BMP2 to increase p53 expression, caspase activation and oxidative stress. This study provides direct evidence for modifying effects of the environment in a genetic mouse model carrying a predisposing mutation for HPE in the Twsg1 gene. Further study of the mechanisms underlying these gene-environment interactions in vivo will contribute to better understanding of the pathogenesis of birth defects and present an opportunity to explore potential preventive interventions.

  18. The Effect of Opsteoporotic Model Rats Induced by Retinoic Acid

    Institute of Scientific and Technical Information of China (English)

    Xu Peng; Yao Jianfeng; Jin Weizhang; Cai Qiankun; Guo Xiong

    2005-01-01

    Objective: To study the effect of retinoic acid on inducing osteoporosis in female rat. Methods: 48SD female rats were divided randomly into experiment group and control group. Retinoic acid was administered orally to experiment group with 80mg.kg-1d-1 for 15 days. Then the rats were sacrificed on the 0th, 30th, 60th days after last administration. The serum concentration of Ca, P, BGP, E2, AKP and TRAP were detected. Components of collagen and proteoglycan in the bones and BMD were also assayed .The femoral morphometric change and epiphyseal plate cartilage histological changes were observed. Results: After a 15-day period treatment with retinoic acid, charateristics of experiment group were compared with control, it is shown that the concentration of serum E2 and BGP declined, the activity of AKP and TRAP increased while BMP decreased, the bone mass of both spongy bone and cortical bone reduced, the number of spongy bone osteoclasts and their activity increased, number of epiphyseal plate chondrocyte reduced, cartilage hypertrophic zone displayed dyscalcification, and no difference of other markers was found in the two groups. On the 30th day after the last administration, the experiment group appeared a declined number of cancellous bone osteoclast and level of serum AKP yet they were still higher than control. Number of epiphyseal chondrocyte, serum BGP and tibial BMD, though higher than before, were still lower than control. Other markers were no difference. On the 60th day after treatment, although the femoral cancellous bone mass was still less and cancellous osteoblast was more than control, the cortical bone mass, cancellous osteoclast number and level of serum Ca and P were all remained no different between two groups.Conclusion: Retinoic acid possessed a better short-term effect than long-term effect. Cancellous bone loss lasted much longer than cortical bone and more obviously; the bone matrix in this osteoporosis model was able to repair itself

  19. NR4A orphan nuclear receptors influence retinoic acid and docosahexaenoic acid signaling via up-regulation of fatty acid binding protein 5

    Energy Technology Data Exchange (ETDEWEB)

    Volakakis, Nikolaos; Joodmardi, Eliza [Ludwig Institute for Cancer Research Ltd., Box 240, S-17177 Stockholm (Sweden); Perlmann, Thomas, E-mail: thomas.perlmann@licr.ki.se [Ludwig Institute for Cancer Research Ltd., Box 240, S-17177 Stockholm (Sweden); The Department of Cell and Molecular Biology, Karolinska Institute, S-17177 Stockholm (Sweden)

    2009-12-25

    The orphan nuclear receptor (NR) Nurr1 is expressed in the developing and adult nervous system and is also induced as an immediate early gene in a variety of cell types. In silico analysis of human promoters identified fatty acid binding protein 5 (FABP5), a protein shown to enhance retinoic acid-mediated PPAR{beta}/{delta} signaling, as a potential Nurr1 target gene. Nurr1 has previously been implicated in retinoid signaling via its heterodimerization partner RXR. Since NRs are commonly involved in cross-regulatory control we decided to further investigate the regulatory relationship between Nurr1 and FABP5. FABP5 expression was up-regulated by Nurr1 and other NR4A NRs in HEK293 cells, and Nurr1 was shown to activate and bind to the FABP5 promoter, supporting that FABP5 is a direct downstream target of NR4A NRs. We also show that the RXR ligand docosahexaenoic acid (DHA) can induce nuclear translocation of FABP5. Moreover, via up-regulation of FABP5 Nurr1 can enhance retinoic acid-induced signaling of PPAR{beta}/{delta} and DHA-induced activation of RXR. We also found that other members of the NR4A orphan NRs can up-regulate FABP5. Thus, our findings suggest that NR4A orphan NRs can influence signaling events of other NRs via control of FABP5 expression levels.

  20. A new module in neural differentiation control: two microRNAs upregulated by retinoic acid, miR-9 and -103, target the differentiation inhibitor ID2.

    Directory of Open Access Journals (Sweden)

    Daniela Annibali

    Full Text Available The transcription factor ID2 is an important repressor of neural differentiation strongly implicated in nervous system cancers. MicroRNAs (miRNAs are increasingly involved in differentiation control and cancer development. Here we show that two miRNAs upregulated on differentiation of neuroblastoma cells--miR-9 and miR-103--restrain ID2 expression by directly targeting the coding sequence and 3' untranslated region of the ID2 encoding messenger RNA, respectively. Notably, the two miRNAs show an inverse correlation with ID2 during neuroblastoma cell differentiation induced by retinoic acid. Overexpression of miR-9 and miR-103 in neuroblastoma cells reduces proliferation and promotes differentiation, as it was shown to occur upon ID2 inhibition. Conversely, an ID2 mutant that cannot be targeted by either miRNA prevents retinoic acid-induced differentiation more efficient than wild-type ID2. These findings reveal a new regulatory module involving two microRNAs upregulated during neural differentiation that directly target expression of the key differentiation inhibitor ID2, suggesting that its alteration may be involved in neural cancer development.

  1. Retinoic acid represses CYP7A1 expression in human hepatocytes and HepG2 cells by FXR/RXR-dependent and independent mechanisms.

    Science.gov (United States)

    Cai, Shi-Ying; He, Hongwei; Nguyen, Trong; Mennone, Albert; Boyer, James L

    2010-08-01

    Cholesterol 7alpha-hydroxylase (CYP7A1) plays a key role in maintaining lipid and bile salt homeostasis as it is the rate-limiting enzyme converting cholesterol to bile acids. Deficiency of CYP7A1 leads to hyperlipidemia in man and mouse. Hyperlipidemia is often seen in patients when treated with high-dose retinoic acid (RA), but the molecular mechanisms remain elusive. Our present study revealed that CYP7A1 mRNA expression is greatly repressed by RA in both human hepatocytes and HepG2 cells where increased fibroblast growth factor 19 (FGF19) and small heterodimer partner (SHP) expressions were also observed, suggesting farnesoid X receptor (FXR) and retinoid X receptor (RXR) were activated. Promoter reporter assays demonstrate that all-trans RA (atRA) specifically activated FXR/RXR. However, detailed molecular analyses indicate that this activation is through RXR, whose ligand is 9-cis RA. Knocking down of FXR or RXRalpha by small interference RNA (siRNA) in human hepatocytes increased CYP7A1 basal expression, but the repressive effect of atRA persisted, suggesting there are also FXR/RXR-independent mechanisms mediating atRA repression of CYP7A1 expression. Chromatin immunoprecipitation (ChIP) assay and cell transfection results indicate that PGC-1alpha plays a role in the FXR/RXR-independent mechanism. Our findings may provide a potential explanation for hyperlipidemic side effects observed in some patients treated with high-dose RA.

  2. AM580, a stable benzoic derivative of retinoic acid, has powerful and selective cyto-differentiating effects on acute promyelocytic leukemia cells.

    Science.gov (United States)

    Gianní, M; Li Calzi, M; Terao, M; Guiso, G; Caccia, S; Barbui, T; Rambaldi, A; Garattini, E

    1996-02-15

    All-trans retinoic acid (ATRA) is successfully used in the cyto-differentiating treatment of acute promyelocytic leukemia (APL). Paradoxically, APL cells express PML-RAR, an aberrant form of the retinoic acid receptor type alpha (RAR alpha) derived from the leukemia-specific t(15;17) chromosomal translocation. We show here that AM580, a stable retinobenzoic derivative originally synthesized as a RAR alpha agonist, is a powerful inducer of granulocytic maturation in NB4, an APL-derived cell line, and in freshly isolated APL blasts. After treatment of APL cells with AM580 either alone or in combination with granulocyte colony-stimulating factor (G-CSF), the compound induces granulocytic maturation, as assessed by determination of the levels of leukocyte alkaline phosphatase, CD11b, CD33, and G-CSF receptor mRNA, at concentrations that are 10- to 100-fold lower than those of ATRA necessary to produce similar effects. By contrast, AM580 is not effective as ATRA in modulating the expression of these differentiation markers in the HL-60 cell line and in freshly isolated granulocytes obtained from the peripheral blood of chronic myelogenous leukemia patients during the stable phase of the disease. In NB4 cells, two other synthetic nonselective RAR ligands are capable of inducing LAP as much as AM580, whereas RAR beta- or RAR gamma-specific ligands are totally ineffective. These results show that AM580 is more powerful than ATRA in modulating the expression of differentiation antigens only in cells in which PML-RAR is present. Binding experiments, using COS-7 cells transiently transfected with PML-RAR and the normal RAR alpha, show that AM580 has a lower affinity than ATRA for both receptors. However, in the presence of PML-RAR, the synthetic retinoid is a much better transactivator of retinoic acid-responsive element-containing promoters than the natural retinoid, whereas, in the presence of RAR alpha, AM580 and ATRA have similar activity. This may explain the strong cyto

  3. 维甲酸导致胎鼠神经脊源性器官异常%Retinoic acid induce neural creast-derived malformations in rat

    Institute of Scientific and Technical Information of China (English)

    余家康; 夏慧敏; Gonzalez S; Diez Pardo JA; Tovar JA

    2003-01-01

    为证实我们的假设,即维甲酸物质不但能导致胎鼠颅面部的畸形,而且还能造成胸颈部内分泌腺(胸腺、甲状腺和甲状旁腺)的异常,这些器官的形成都是与神经脊细胞的移入有关的.于孕期第10天给母鼠125mg/kg全反型维甲酸(All-franretinoicacid),对照组给予相应量的载体溶液.分娩前24小时剖腹取出胎鼠,10%福尔马林浸泡固定10天,双管手术显微镜下解剖,检查颅、面部,心脏,大血管,胸腺,并对甲状腺,甲状旁腺进行组织学研究.对照组10只胎鼠未发现畸形,而实验组20只胎鼠中,有17只(85%)出现颅面部畸形,14只(70%)有心血管畸形,而胸腺、甲状腺、甲状旁腺和甲状腺畸形分别有14只(70%)、15只(75%)和7只(35%).结果表明,维甲酸能导致胎鼠中鳃弓衍化而成并需神经脊参与的器官组织结构异常.

  4. Retinoic acid inducing skeletal malformations in fetal rat model%维甲酸致胎鼠骨骼畸形模型的建立

    Institute of Scientific and Technical Information of China (English)

    余家康; 夏慧敏; Juan A Tovar

    2006-01-01

    目的 利用维甲酸胎鼠模型,观察其骨骼畸形出现的情况,探讨骨骼畸形的发生机制.方法 于孕期第10天经胃管给SD母鼠注入125 mg/kg体重全反式维甲酸,对照组仅予载体溶液.分娩前24 h剖腹取出胎鼠,实验组和对照组分别随机各取20只和10只胎鼠去除软组织,行骨软骨双重染色法,显微镜观察骨骼情况.结果 实验组胎鼠体重(4.294±0.670)g与对照组(4.743±0.542)g比较,差异有统计学意义(P<0.05).对照组未见骨骼畸形.维甲酸组有18只(90%)胎鼠可见明显的全身骨骼畸形,最常见的畸形分别是长骨畸形(80%)、腕掌跗跖骨缺如(80%)、胸廓外形异常(80%)、椎体畸形(75%)、骨盆畸形(70)和脊椎裂(65%).结论 维甲酸有较强的胎鼠骨骼致畸作用,这种作用是多部位的.维甲酸大鼠是研究骨骼先天性畸形的实用工具模型.

  5. Herpes simplex virus infection is sensed by both Toll-like receptors and retinoic acid-inducible gene- like receptors, which synergize to induce type I interferon production

    DEFF Research Database (Denmark)

    Rasmussen, Simon Brandtoft; Jensen, Søren B; Nielsen, C;

    2009-01-01

    interferons (IFNs) after infection with herpes simplex virus (HSV). Our work also identified RNase L as a critical component in IFN induction. Moreover, we found that TLR9 and RLRs activate distinct, as well as overlapping, intracellular signalling pathways. Thus, RLRs are important for recognition of HSV...

  6. Structure and rheological properties of acid-induced egg white protein gels

    NARCIS (Netherlands)

    Weijers, M.; Velde, van de F.; Stijnman, A.; Pijpekamp, van de A.; Visschers, R.W.

    2006-01-01

    This study compares the rheological properties of acid-induced gels prepared of industrial spray-dried egg white proteins (EWP) with the acid-induced gels prepared of ovalbumin (OA) and whey protein isolate (WPI). Also we aimed to form transparent gels of EWP by means of the cold-gelation process. W

  7. Sphingoid bases inhibit acid-induced demineralization of hydroxyapatite.

    Science.gov (United States)

    Valentijn-Benz, Marianne; van 't Hof, Wim; Bikker, Floris J; Nazmi, Kamran; Brand, Henk S; Sotres, Javier; Lindh, Liselott; Arnebrant, Thomas; Veerman, Enno C I

    2015-01-01

    Calcium hydroxyapatite (HAp), the main constituent of dental enamel, is inherently susceptible to the etching and dissolving action of acids, resulting in tooth decay such as dental caries and dental erosion. Since the prevalence of erosive wear is gradually increasing, there is urgent need for agents that protect the enamel against erosive attacks. In the present study we studied in vitro the anti-erosive effects of a number of sphingolipids and sphingoid bases, which form the backbone of sphingolipids. Pretreatment of HAp discs with sphingosine, phytosphingosine (PHS), PHS phosphate and sphinganine significantly protected these against acid-induced demineralization by 80 ± 17%, 78 ± 17%, 78 ± 7% and 81 ± 8%, respectively (p measurement revealed that HAp discs treated with PHS were almost completely and homogeneously covered by patches of PHS. This suggests that PHS and other sphingoid bases form layers on the surface of HAp, which act as diffusion barriers against H(+) ions. In principle, these anti-erosive properties make PHS and related sphingosines promising and attractive candidates as ingredients in oral care products.

  8. Metformin protects rat hepatocytes against bile acid-induced apoptosis.

    Directory of Open Access Journals (Sweden)

    Titia E Woudenberg-Vrenken

    Full Text Available BACKGROUND: Metformin is used in the treatment of Diabetes Mellitus type II and improves liver function in patients with non-alcoholic fatty liver disease (NAFLD. Metformin activates AMP-activated protein kinase (AMPK, the cellular energy sensor that is sensitive to changes in the AMP/ATP-ratio. AMPK is an inhibitor of mammalian target of rapamycin (mTOR. Both AMPK and mTOR are able to modulate cell death. AIM: To evaluate the effects of metformin on hepatocyte cell death. METHODS: Apoptotic cell death was induced in primary rat hepatocytes using either the bile acid glycochenodeoxycholic acid (GCDCA or TNFα in combination with actinomycin D (actD. AMPK, mTOR and phosphoinositide-3 kinase (PI3K/Akt were inhibited using pharmacological inhibitors. Apoptosis and necrosis were quantified by caspase activation, acridine orange staining and Sytox green staining respectively. RESULTS: Metformin dose-dependently reduces GCDCA-induced apoptosis, even when added 2 hours after GCDCA, without increasing necrotic cell death. Metformin does not protect against TNFα/ActD-induced apoptosis. The protective effect of metformin is dependent on an intact PI3-kinase/Akt pathway, but does not require AMPK/mTOR-signaling. Metformin does not inhibit NF-κB activation. CONCLUSION: Metformin protects against bile acid-induced apoptosis and could be considered in the treatment of chronic liver diseases accompanied by inflammation.

  9. Retinoic acid signalling in thymocytes regulates T cell development

    DEFF Research Database (Denmark)

    Wendland, Kerstin; Sitnik, Katarzyna Maria; Kotarsky, Knut

    The Vitamin A derivative retinoic acid (RA) has emerged as an important regulator of peripheral T cell responses. However, whether there is endogenous retinoic acid receptor (RAR) signaling in developing thymocytes and the potential impact of such signals in thymocyte development remains unclear...... further enhanced in recently generated CD69+ CD4+ SP cells. To address the potential biological significance of RA signaling in developing thymocytes, we evaluated T cell development in CD4Cre-dnRAR mice, where RA signaling is blocked in thymocytes from the CD4+CD8+ double positive (DP) stage onwards due...... of this cell subset. Collectively, our data suggest a direct role for RA signaling in regulating thymocyte homeostasis and T cell development....

  10. Oral Administration of a Retinoic Acid Receptor Antagonist Reversibly Inhibits Spermatogenesis in Mice

    OpenAIRE

    Chung, Sanny S. W.; Wang, Xiangyuan; Roberts, Shelby S.; Stephen M Griffey; Reczek, Peter R.; Wolgemuth, Debra J.

    2011-01-01

    Meeting men's contraceptive needs, orally administered retinoic acid receptor antagonists represent new lead molecules in developing non-hormonal, reversible male contraceptives without adverse side effects.

  11. Investigation of the Role of All-Trans Retinoid Acid in Inducing Differentiation of Retinoblastoma in Vivo%维甲酸诱导分化视网膜母细胞瘤的机理研究

    Institute of Scientific and Technical Information of China (English)

    王艳; 高解春; 董岿然; 陈莲; 王舒宜

    2011-01-01

    Objective To investigate the role and possible mechanism of all-trans retinoid acid in inducing differentiation of retinoblastoma in nude mice. Methods SO-RB50 suspense cell mixture was injected into bilateral armpits of male nude mice, and model of retinoblastoma nude mice was established. The size and weight of tumors were observed twice every week ,tumors' structure were recorded under microscope and electro-microscope, tumors' DNA index was calculated, relative quantities of gene CyclinDl ,CDK4 and ICAM-1 were measured by trans-transcription polymerase chain reaction and fluorescent quantity. Results At the end of the experiment, average tumor weight of ATRA group( 2. 750± 0. 302 ) g was lower than that of control group ( 7.150 ±1. 228 ) g( P = 0.008 ), and average tumor weight of Vitamin A deficient group( 11. 483 ± 2. 271 ) g( P = 0. 003 ). Under microscope, necrosis without inflammation was found in retinoblastoma cells in ATRA group, cells in control group appeared the same as those in original xenograft, retinoblastom cells in Vitamin A deficient group had a higher nuclear-plasma ratio than that of control group. Under electro-microscope, retinoblastoma cells in ATRA group contained swelled and bubble-like mitochondrion and much less ribosomes than those in control group. Cells in Vitamin A deficient group contained more free ribosomes and less lysosomes in the plasma than those in control group. Trans-transcription PCR and fluorescent quantity showed the relative quantity of CyclinD1 was the lowest in ATRA group( P =0.012) and highest in Vitamin A deficient group( P =0.017 ) ;the relative quantity of CDK4 was lowest in ATRA group(P =0.010) and highest in Vitamin A deficient group( P =0. 029). There was no statistical significance in ICAM-1 between ATRA group and control group(P =0.071 ) or between Vitamin A deficient group and control group ( P= 0.083 ). Conclusion The growth of retinoblastoma xenograft in ATRA group was restrained by ATRA, and Vitamin

  12. High dose of ascorbic acid induces cell death in mesothelioma cells.

    Science.gov (United States)

    Takemura, Yukitoshi; Satoh, Motohiko; Satoh, Kiyotoshi; Hamada, Hironobu; Sekido, Yoshitaka; Kubota, Shunichiro

    2010-04-02

    Malignant mesothelioma is an asbestos-related fatal disease with no effective cure. Recently, high dose of ascorbate in cancer treatment has been reexamined. We studied whether high dose of ascorbic acid induced cell death of four human mesothelioma cell lines. High dose of ascorbic acid induced cell death of all mesothelioma cell lines in a dose-dependent manner. We further clarified the cell killing mechanism that ascorbic acid induced reactive oxygen species and impaired mitochondrial membrane potential. In vivo experiment, intravenous administration of ascorbic acid significantly decreased the growth rate of mesothelioma tumor inoculated in mice. These data suggest that ascorbic acid may have benefits for patients with mesothelioma.

  13. Retinoic acid is a potential dorsalising signal in the late embryonic chick hindbrain

    Directory of Open Access Journals (Sweden)

    Maden Malcolm

    2007-12-01

    Full Text Available Abstract Background Human retinoic acid teratogenesis results in malformations of dorsally derived hindbrain structures such as the cerebellum, noradrenergic hindbrain neurons and the precerebellar system. These structures originate from the rhombic lip and adjacent dorsal precursor pools that border the fourth ventricle roofplate. While retinoic acid synthesis is known to occur in the meninges that blanket the hindbrain, the particular sensitivity of only dorsal structures to disruptions in retinoid signalling is puzzling. We therefore looked for evidence within the neural tube for more spatiotemporally specific signalling pathways using an in situ hybridisation screen of known retinoic acid pathway transcripts. Results We find that there are highly restricted domains of retinoic acid synthesis and breakdown within specific hindbrain nuclei as well as the ventricular layer and roofplate. Intriguingly, transcripts of cellular retinoic acid binding protein 1 are always found at the interface between dividing and post-mitotic cells. By contrast to earlier stages of development, domains of synthesis and breakdown in post-mitotic neurons are co-localised. At the rhombic lip, expression of the mRNA for retinoic acid synthesising and catabolising enzymes is spatially highly organised with respect to the Cath1-positive precursors of migratory precerebellar neurons. Conclusion The late developing hindbrain shows patterns of retinoic acid synthesis and use that are distinct from the well characterised phase of rostrocaudal patterning. Selected post-mitotic populations, such as the locus coeruleus, appear to both make and break down retinoic acid suggesting that a requirement for an autocrine, or at least a highly localised paracrine signalling network, might explain its acute sensitivity to retinoic acid disruption. At the rhombic lip, retinoic acid is likely to act as a dorsalising factor in parallel with other roofplate signalling pathways. While its

  14. Extracellular and intracellular arachidonic acid-induced contractions in rat aorta

    NARCIS (Netherlands)

    Filipeanu, CM; Brailoiu, E; Petrescu, G; Nelemans, SA

    1998-01-01

    Arachidonic acid induced contractions of de-endothelized rat aortic rings. A more potent effect was obtained after intracellular administration of arachidonic acid using liposomes. Contractions induced by extracellular arachidonic acid were inhibited similarly to phenylephrine-induced contractions b

  15. PHARMACOKINETICS OF PARENTERAL 13-CIS-RETINOIC ACID FORMULATIONS IN RATS

    NARCIS (Netherlands)

    GUCHELAAR, HJ; BEUKEVELD, GJJ; MULDER, NH; OOSTERHUIS, JW; Wouda, S.

    1992-01-01

    The pharmacokinetics of three 13-cis-retinoic acid formulations were studied after intraperitoneal (ip) administration to rats. Rats were given ip injections of 2.5 mg of 13-cis-retinoic acid per 360 g of body weight; the drug was administered as an alkaline solution, suspended in corn oil, or as a

  16. Dysregulated microRNA clusters in response to retinoic acid and CYP26B1 inhibitor induced testicular function in dogs.

    Directory of Open Access Journals (Sweden)

    Vanmathy R Kasimanickam

    Full Text Available Spermatogenesis is a multistep synchronized process. Diploid spermatogonia differentiate into haploid spermatozoa following mitosis, meiosis and spermiogenesis. Division and differentiation of male germ cells is achieved through the sequential expression of several genes. Numerous mRNAs in the differentiating germ cells undergo post-transcriptional and translational regulation. MiRNAs are powerful negative regulators of mRNA transcription, stability, and translation and recognize their mRNA targets through base-pairing. Retinoic acid (RA signaling is essential for spermatogenesis and testicular function. Testicular RA level is critical for RA signal transduction. This study investigated the miRNAs modulation in an RA- induced testicular environment following the administration of all-trans RA (2 µM and CYP26B1- inhibitor (1 µM compared to control. Eighty four canine mature miRNAs were analyzed and their expression signatures were distinguished using real-time PCR based array technology. Of the miRNAs analyzed, miRNA families such as miR-200 (cfa-miR-200a, cfa-miR-200b and cfa-miR-200c, Mirlet-7 (cfa-let-7a, cfa-let-7b, cfa-let-7c, cfa-let-7g and cfa-let-7f, miR-125 (cfa-miR-125a and cfa-miR-125b, miR-146 (cfa-miR-146a and cfa-miR-146b, miR-34 (cfa-miR-34a, cfa-miR-34b and cfa-miR-34c, miR-23 (cfa-miR-23a and cfa-miR-23b, cfa-miR-184, cfa-miR-214 and cfa-miR-141 were significantly up-regulated with testicular RA intervention via administration of CYP26B1 inhibitor and all-trans-RA and species of miRNA such as cfa-miR-19a, cfa-miR-29b, cfa-miR-29c, cfa-miR-101 and cfa-miR-137 were significantly down-regulated. This study explored information regarding chromosome distribution, human orthologous sequences and the interaction of target genes of miRNA families significantly distinguished in this study using prediction algorithms. This study importantly identified dysregulated miRNA species resulting from RA-induced spermatogenesis. The present

  17. Direct visualization of retinoic acid in the rat hypothalamus: an immunohistochemical study.

    Science.gov (United States)

    Mangas, A; Bodet, D; Duleu, S; Yajeya, J; Geffard, M; Coveñas, R

    2012-02-10

    In order to increase our knowledge about the distribution of vitamins in the mammalian brain, we have developed a highly specific antiserum directed against retinoic acid with good affinity (10(-8) M), as evaluated by ELISA tests. In the rat brain, no immunoreactive fibers containing retinoic acid were detected. Cell bodies containing retinoic acid were only found in the hypothalamus. This work reports the first visualization and the morphological characteristics of cell bodies containing retinoic acid in the mammalian paraventricular hypothalamic nucleus and in the dorsal perifornical region, using an indirect immunoperoxidase technique. The restricted distribution of retinoic acid in the rat brain suggests that this vitamin could be involved in very specific physiological mechanisms.

  18. Retinoic acid, meiosis and germ cell fate in mammals.

    Science.gov (United States)

    Bowles, Josephine; Koopman, Peter

    2007-10-01

    Although mammalian sex is determined genetically, the sex-specific development of germ cells as sperm or oocytes is initiated by cues provided by the gonadal environment. During embryogenesis, germ cells in an ovary enter meiosis, thereby committing to oogenesis. By contrast, germ cells in a testicular environment do not enter meiosis until puberty. Recent findings indicate that the key to this sex-specific timing of meiosis entry is the presence or absence of the signaling molecule retinoic acid. Although this knowledge clarifies a long-standing mystery in reproductive biology, it also poses many new questions, which we discuss in this review.

  19. Improved Outcomes With Retinoic Acid and Arsenic Trioxide Compared With Retinoic Acid and Chemotherapy in Non-High-Risk Acute Promyelocytic Leukemia: Final Results of the Randomized Italian-German APL0406 Trial.

    Science.gov (United States)

    Platzbecker, Uwe; Avvisati, Giuseppe; Cicconi, Laura; Thiede, Christian; Paoloni, Francesca; Vignetti, Marco; Ferrara, Felicetto; Divona, Mariadomenica; Albano, Francesco; Efficace, Fabio; Fazi, Paola; Sborgia, Marco; Di Bona, Eros; Breccia, Massimo; Borlenghi, Erika; Cairoli, Roberto; Rambaldi, Alessandro; Melillo, Lorella; La Nasa, Giorgio; Fiedler, Walter; Brossart, Peter; Hertenstein, Bernd; Salih, Helmut R; Wattad, Mohammed; Lübbert, Michael; Brandts, Christian H; Hänel, Mathias; Röllig, Christoph; Schmitz, Norbert; Link, Hartmut; Frairia, Chiara; Pogliani, Enrico Maria; Fozza, Claudio; D'Arco, Alfonso Maria; Di Renzo, Nicola; Cortelezzi, Agostino; Fabbiano, Francesco; Döhner, Konstanze; Ganser, Arnold; Döhner, Hartmut; Amadori, Sergio; Mandelli, Franco; Ehninger, Gerhard; Schlenk, Richard F; Lo-Coco, Francesco

    2017-02-20

    Purpose The initial results of the APL0406 trial showed that the combination of all- trans-retinoic acid (ATRA) and arsenic trioxide (ATO) is at least not inferior to standard ATRA and chemotherapy (CHT) in first-line therapy of low- or intermediate-risk acute promyelocytic leukemia (APL). We herein report the final analysis on the complete series of patients enrolled onto this trial. Patients and Methods The APL0406 study was a prospective, randomized, multicenter, open-label, phase III noninferiority trial. Eligible patients were adults between 18 and 71 years of age with newly diagnosed, low- or intermediate-risk APL (WBC at diagnosis ≤ 10 × 10(9)/L). Overall, 276 patients were randomly assigned to receive ATRA-ATO or ATRA-CHT between October 2007 and January 2013. Results Of 263 patients evaluable for response to induction, 127 (100%) of 127 patients and 132 (97%) of 136 patients achieved complete remission (CR) in the ATRA-ATO and ATRA-CHT arms, respectively ( P = .12). After a median follow-up of 40.6 months, the event-free survival, cumulative incidence of relapse, and overall survival at 50 months for patients in the ATRA-ATO versus ATRA-CHT arms were 97.3% v 80%, 1.9% v 13.9%, and 99.2% v 92.6%, respectively ( P < .001, P = .0013, and P = .0073, respectively). Postinduction events included two relapses and one death in CR in the ATRA-ATO arm and two instances of molecular resistance after third consolidation, 15 relapses, and five deaths in CR in the ATRA-CHT arm. Two patients in the ATRA-CHT arm developed a therapy-related myeloid neoplasm. Conclusion These results show that the advantages of ATRA-ATO over ATRA-CHT increase over time and that there is significantly greater and more sustained antileukemic efficacy of ATO-ATRA compared with ATRA-CHT in low- and intermediate-risk APL.

  20. Retinoic acid binding protein in normal and neopolastic rat prostate.

    Science.gov (United States)

    Gesell, M S; Brandes, M J; Arnold, E A; Isaacs, J T; Ueda, H; Millan, J C; Brandes, D

    1982-01-01

    Sucrose density gradient analysis of cytosol from normal and neoplastic rat prostatic tissues exhibited a peak of (3H) retinoic acid binding in the 2S region, corresponding to the cytoplasmic retinoic acid binding protein (cRABP). In the Fisher-Copenhagen F1 rat, cRABP was present in the lateral lobe, but could not be detected in the ventral nor in the dorsal prostatic lobes. Four sublines of the R-3327 rat prostatic tumor contained similar levels of this binding protein. The absence of cRABP in the normal tissue of origin of the R-3327 tumor, the rat dorsal prostate, and reappearance in the neoplastic tissues follows a pattern described in other human and animal tumors. The occurrence of cRABP in the well-differentiated as well as in the anaplastic R-3327 tumors in which markers which reflect a state of differentiation and hormonal regulation, such as androgen receptor, 5 alpha reductase, and secretory acid phosphatase are either markedly reduced or absent, points to cRABP as a marker of malignant transformation.

  1. Roflumilast enhances the renal protective effects of retinoids in an HIV-1 transgenic mouse model of rapidly progressive renal failure.

    Science.gov (United States)

    Zhong, Yifei; Wu, Yingwei; Liu, Ruijie; Deng, Yueyi; Mallipattu, Sandeep K; Klotman, Paul E; Chuang, Peter Y; He, John C

    2012-05-01

    Retinoic acid decreases proteinuria and glomerulosclerosis in several animal models of kidney disease by protecting podocytes from injury. Our recent in vitro studies suggest that all-trans retinoic acid induces podocyte differentiation by activating the retinoic acid receptor-α (RARα)/cAMP/PKA/CREB pathway. When used in combination with all-trans retinoic acid, an inhibitor of phosphodiesterase 4 further enhanced podocyte differentiation by increasing intracellular cAMP. Additionally, we found that Am580, a specific RARα agonist, has similar renal protective effects as all-trans retinoic acid in a rederived colony of HIV-1 transgenic mice with rapidly progressive renal failure (HIV-Tg) that mimics human HIV-associated nephropathy. Treatment with either the inhibitor of phosphodiesterase 4, roflumilast, or Am580 significantly reduced proteinuria, attenuated kidney injury, and improved podocyte differentiation in these HIV-Tg mice. Additional renal protective effects were found when roflumilast was combined with Am580. Consistent with the in vitro data, glomeruli from HIV-Tg mice treated with both Am580 and roflumilast had more active phosphorylated CREB than with either agent alone. Thus, phosphodiesterase 4 inhibitors could be used in combination with RARα agonists to provide additional renal protection.

  2. Identification and characterization of nucleolin as a COUP-TFII coactivator of retinoic acid receptor β transcription in breast cancer cells.

    Directory of Open Access Journals (Sweden)

    Lacey M Litchfield

    Full Text Available INTRODUCTION: The orphan nuclear receptor COUP-TFII plays an undefined role in breast cancer. Previously we reported lower COUP-TFII expression in tamoxifen/endocrine-resistant versus sensitive breast cancer cell lines. The identification of COUP-TFII-interacting proteins will help to elucidate its mechanism of action as a transcriptional regulator in breast cancer. RESULTS: FLAG-affinity purification and multidimensional protein identification technology (MudPIT identified nucleolin among the proteins interacting with COUP-TFII in MCF-7 tamoxifen-sensitive breast cancer cells. Interaction of COUP-TFII and nucleolin was confirmed by coimmunoprecipitation of endogenous proteins in MCF-7 and T47D breast cancer cells. In vitro studies revealed that COUP-TFII interacts with the C-terminal arginine-glycine repeat (RGG domain of nucleolin. Functional interaction between COUP-TFII and nucleolin was indicated by studies showing that siRNA knockdown of nucleolin and an oligonucleotide aptamer that targets nucleolin, AS1411, inhibited endogenous COUP-TFII-stimulated RARB2 expression in MCF-7 and T47D cells. Chromatin immunoprecipitation revealed COUP-TFII occupancy of the RARB2 promoter was increased by all-trans retinoic acid (atRA. RARβ2 regulated gene RRIG1 was increased by atRA and COUP-TFII transfection and inhibited by siCOUP-TFII. Immunohistochemical staining of breast tumor microarrays showed nuclear COUP-TFII and nucleolin staining was correlated in invasive ductal carcinomas. COUP-TFII staining correlated with ERα, SRC-1, AIB1, Pea3, MMP2, and phospho-Src and was reduced with increased tumor grade. CONCLUSIONS: Our data indicate that nucleolin plays a coregulatory role in transcriptional regulation of the tumor suppressor RARB2 by COUP-TFII.

  3. DHRS3, a retinal reductase, is differentially regulated by retinoic acid and lipopolysaccharide-induced inflammation in THP-1 cells and rat liver.

    Science.gov (United States)

    Zolfaghari, Reza; Chen, Qiuyan; Ross, A Catharine

    2012-09-01

    Both retinoid status and inflammation have been shown to control the level of expression of retinoid homeostatic genes. In the present study, DHRS3, previously shown to possess retinal reductase activity, was identified by microarray analysis of THP-1 monocytes as a possible gene target of all-trans-retinoic acid (RA). In these cells, DHRS3 mRNA increased 30- to 40-fold after treatment with ≤20 nM RA for 24 h, while DHRS3 protein also increased. Of several synthetic retinoids tested, only Am580, a RA receptor-α-selective retinoid, increased DHRS3 mRNA expression. The full-length DHRS3 cDNA was cloned from rat liver and subjected to in vitro transcription-translation. Two major ∼30- and 35-kDa proteins were detected. In adult rat tissues, DHRS3 mRNA was most abundant in the adrenal gland, liver, and ovary. In the liver, DHRS3 is expressed in hepatocytes and possibly in all liver cells. To evaluate whether DHRS3 is regulated in the liver by RA and/or inflammatory stimuli, we treated rats for 6 h with RA or LPS or both. DHRS3 mRNA was doubled by RA but reduced by >90% after treatment with LPS in the absence and presence of RA. On the basis of our results, DHRS3 mRNA expression is regulated by RA in a tissue- or cell-type specific manner; the RA-induced increase in DHRS3 may contribute to retinoid storage; and a reduction of DHRS3 expression in the liver during inflammation may contribute to the perturbation of whole body vitamin A metabolism that has previously been shown to occur in conditions of inflammatory stress.

  4. PKCδ Regulates Translation Initiation through PKR and eIF2α in Response to Retinoic Acid in Acute Myeloid Leukemia Cells

    Directory of Open Access Journals (Sweden)

    Bulent Ozpolat

    2012-01-01

    Full Text Available Translation initiation and activity of eukaryotic initiation factor-alpha (eIF2α, the rate-limiting step of translation initiation, is often overactivated in malignant cells. Here, we investigated the regulation and role of eIF2α in acute promyelocytic (APL and acute myeloid leukemia (AML cells in response to all-trans retinoic acid (ATRA and arsenic trioxide (ATO, the front-line therapies in APL. ATRA and ATO induce Ser-51 phosphorylation (inactivation of eIF2α, through the induction of protein kinase C delta (PKCδ and PKR, but not other eIF2α kinases, such as GCN2 and PERK in APL (NB4 and AML cells (HL60, U937, and THP-1. Inhibition of eIF2α reduced the expression of cellular proteins that are involved in apoptosis (DAP5/p97, cell cycle (p21Waf1/Cip1, differentiation (TG2 and induced those regulating proliferation (c-myc and survival (p70S6K. PI3K/Akt/mTOR pathway is involved in regulation of eIF2α through PKCδ/PKR axis. PKCδ and p-eIF2α protein expression levels revealed a significant association between the reduced levels of PKCδ (P=0.0378 and peIF2 (P=0.0041 and relapses in AML patients (n=47. In conclusion, our study provides the first evidence that PKCδ regulates/inhibits eIF2α through induction of PKR in AML cells and reveals a novel signaling mechanism regulating translation initiation.

  5. IRF4 Is a Critical Gene in Retinoic Acid-Mediated Plasma Cell Formation and Is Deregulated in Common Variable Immunodeficiency-Derived B Cells.

    Science.gov (United States)

    Indrevær, Randi L; Moskaug, Jan Ø; Paur, Ingvild; Bøhn, Siv K; Jørgensen, Silje F; Blomhoff, Rune; Aukrust, Pål; Fevang, Børre; Blomhoff, Heidi K

    2015-09-15

    In the present study, we aimed at identifying the mechanisms whereby the vitamin A metabolite all-trans retinoic acid (RA) promotes the formation of plasma cells upon stimulation of B cells via the innate immunity receptors TLR9 and RP105. Most often, differentiation of B cells involves the sequential events of class switch recombination and somatic hypermutations characteristic of germinal center reactions, followed by plasma cell formation. By studying the regulatory networks known to drive these reactions, we revealed that RA enhances the expression of the plasma cell-generating transcription factors IFN regulatory factor (IRF)4 and Blimp1, and paradoxically also activation-induced deaminase (AID) involved in somatic hypermutations/class switch recombination, in primary human B cells. IRF4 was identified as a particularly important protein involved in the RA-mediated production of IgG in TLR9/RP105-stimulated B cells. Based on kinetic studies, we present a model suggesting that the initial induction of IRF4 by RA favors AID expression. According to this model, the higher level of IRF4 that eventually arises results in sustained elevated levels of Blimp1. Regarded as a master regulator of plasma cell development, Blimp1 will in turn suppress AID expression and drive the formation of IgG-secreting plasma cells. Notably, we demonstrated IRF4 to be deregulated in B cells from common variable immunodeficiency patients, contributing to the observed aberrant expression of AID in these patients. Taken together, the present study both provides new insight into the mechanisms whereby RA induces differentiation of B cells and identifies IRF4 as a key to understand the defective functions of B cells in common variable immunodeficiency patients.

  6. Retinoic acid from the meninges regulates cortical neuron generation.

    Science.gov (United States)

    Siegenthaler, Julie A; Ashique, Amir M; Zarbalis, Konstantinos; Patterson, Katelin P; Hecht, Jonathan H; Kane, Maureen A; Folias, Alexandra E; Choe, Youngshik; May, Scott R; Kume, Tsutomu; Napoli, Joseph L; Peterson, Andrew S; Pleasure, Samuel J

    2009-10-30

    Extrinsic signals controlling generation of neocortical neurons during embryonic life have been difficult to identify. In this study we demonstrate that the dorsal forebrain meninges communicate with the adjacent radial glial endfeet and influence cortical development. We took advantage of Foxc1 mutant mice with defects in forebrain meningeal formation. Foxc1 dosage and loss of meninges correlated with a dramatic reduction in both neuron and intermediate progenitor production and elongation of the neuroepithelium. Several types of experiments demonstrate that retinoic acid (RA) is the key component of this secreted activity. In addition, Rdh10- and Raldh2-expressing cells in the dorsal meninges were either reduced or absent in the Foxc1 mutants, and Rdh10 mutants had a cortical phenotype similar to the Foxc1 null mutants. Lastly, in utero RA treatment rescued the cortical phenotype in Foxc1 mutants. These results establish RA as a potent, meningeal-derived cue required for successful corticogenesis.

  7. In silico discovery of novel Retinoic Acid Receptor agonist structures

    Directory of Open Access Journals (Sweden)

    Samuels Herbert H

    2001-06-01

    Full Text Available Abstract Background Several Retinoic Acid Receptors (RAR agonists have therapeutic activity against a variety of cancer types; however, unacceptable toxicity profiles have hindered the development of drugs. RAR agonists presenting novel structural and chemical features could therefore open new avenues for the discovery of leads against breast, lung and prostate cancer or leukemia. Results We have analysed the induced fit of the active site residues upon binding of a known ligand. The derived binding site models were used to dock over 150,000 molecules in silico (or virtually to the structure of the receptor with the Internal Coordinates Mechanics (ICM program. Thirty ligand candidates were tested in vitro. Conclusions Two novel agonists resulting from the predicted receptor model were active at 50 nM. One of them displays novel structural features which may translate into the development of new ligands for cancer therapy.

  8. Expression of retinoic acid receptors in human endometrial carcinoma.

    Science.gov (United States)

    Tanabe, Kojiro; Utsunomiya, Hiroki; Tamura, Mitsutoshi; Niikura, Hitoshi; Takano, Tadao; Yoshinaga, Kohsuke; Nagase, Satoru; Suzuki, Takashi; Ito, Kiyoshi; Matsumoto, Mitsuyo; Hayashi, Shin-ichi; Yaegashi, Nobuo

    2008-02-01

    The retinoids (vitamin A and its biologically active derivatives) are essential for the health and survival of the individual. Several studies have reported a strong rationale for the use of retinoids in cancer treatment and chemoprevention. It has been discovered that expression of retinoic acid receptor (RAR) beta is frequently silenced in epithelial carcinogenesis, which has led to the hypothesis that RAR beta could act as a tumor suppressor. However, the status of RAR beta in human endometrial carcinoma has not been examined. In the present study, we initially studied the effects of retinoic acid on cell proliferation and the expression of RAR alpha, RAR beta, and RAR gamma using AM580 (a RAR-specific agonist) in the Ishikawa endometrial cancer cell line. We also examined the expression of RAR in human eutopic endometrium (30 cases), endometrial hyperplasia (28 cases), and endometrial carcinoma (103 cases) using immunohistochemistry. Finally, we correlated these findings with the clinicopathological parameters. In vitro, cell growth was inhibited and RAR beta and RAR gamma mRNA was significantly induced by AM580, compared with vehicle controls, whereas RAR alpha mRNA was significantly attenuated by AM580, compared with vehicle. RAR beta was detected predominantly in endometrial hyperplasia, compared with endometrial carcinoma. No statistically significant correlation was obtained between the expression of any other RAR subtypes and clinicopathological parameters in human endometrial carcinoma. The results of our study demonstrate that AM580 inhibits cell growth and induces RAR beta mRNA expression in the Ishikawa cell line, and the expression level of RAR beta in endometrial carcinoma is significantly lower than that in endometrial hyperplasia. AM580 might therefore be considered as a potential treatment for endometrial carcinoma.

  9. Signaling by Retinoic Acid in Embryonic and Adult Hematopoiesis

    Directory of Open Access Journals (Sweden)

    Elena Cano

    2014-03-01

    Full Text Available Embryonic and adult hematopoiesis are both finely regulated by a number of signaling mechanisms. In the mammalian embryo, short-term and long-term hematopoietic stem cells (HSC arise from a subset of endothelial cells which constitute the hemogenic endothelium. These HSC expand and give rise to all the lineages of blood cells in the fetal liver, first, and in the bone marrow from the end of the gestation and throughout the adult life. The retinoic acid (RA signaling system, acting through the family of nuclear retinoic acid receptors (RARs and RXRs, is involved in multiple steps of the hematopoietic development, and also in the regulation of the differentiation of some myeloid lineages in adults. In humans, the importance of this RA-mediated control is dramatically illustrated by the pathogeny of acute promyelocytic leukemia, a disease produced by a chromosomal rearrangement fusing the RARa gene with other genes. The aberrant fusion protein is able to bind to RARα target gene promoters to actively suppress gene transcription. Lack of function of RARα leads to a failure in the differentiation of promyelocytic progenitors. In this review we have collected the available information about all the phases of the hematopoietic process in which RA signaling is involved, being essential for steps such as the emergence of HSC from the hemogenic endothelium, or modulating processes such as the adult granulopoiesis. A better knowledge of the RA-mediated signaling mechanisms can contribute to the knowledge of the origin of many pathologies of the hematopoietic system and can provide new clinical avenues for their treatment.

  10. Role of retinoic acid receptors in squamous-cell carcinoma in human esophagus

    DEFF Research Database (Denmark)

    Bergheim, I.; Wolfgarten, E.; Bollschweiler, E.

    2005-01-01

    BACKGROUND: Worldwide, cancer in the esophagus ranks among the 10 most common cancers. Alterations of retinoic acid receptors (e.g. RARalpha, beta, gamma, and RXRalpha, beta, gamma) expression is considered to play an important role in development of squamous-cell carcinoma (SCC), which is the most...... common esophageal cancer. Alcohol consumption and smoking, which can alter retinoic acid receptor levels, have been identified as key risk factors in the development of carcinoma in the aero-digestive tract. Therefore, the aim of the present study was to evaluate protein levels of retinoic acid receptors...... were found for RARalpha, beta, and RXRbeta protein levels between normal esophageal tissue of patients and that of controls. CONCLUSION: In conclusion, results of the present study suggest that alterations of retinoic acid receptors protein may contribute in the development of SCC in esophagus...

  11. Retinoic acid amide inhibits JAK/STAT pathway in lung cancer which leads to apoptosis.

    Science.gov (United States)

    Li, Hong-Xing; Zhao, Wei; Shi, Yan; Li, Ya-Na; Zhang, Lian-Shuang; Zhang, Hong-Qin; Wang, Dong

    2015-11-01

    Small cell lung cancer (SCLC) accounts for 12 to 16% of lung neoplasms and has a high rate of metastasis. The present study demonstrates the antiproliferative effect of retinoic acid amide in vitro and in vivo against human lung cancer cells. The results from MTT assay showed a significant growth inhibition of six tested lung cancer cell lines and inhibition of clonogenic growth at 30 μM. Retinoic acid amide also leads to G2/M-phase cell cycle arrest and apoptosis of lung cancer cells. It caused inhibition of JAK2, STAT3, and STAT5, increased the level of p21WAF1, and decreased cyclin A, cyclin B1, and Bcl-XL expression. Retinoic acid amide exhibited a synergistic effect on antiproliferative effects of methotrexate in lung cancer cells. In lung tumor xenografts, the tumor volume was decreased by 82.4% compared to controls. The retinoic acid amide-treated tumors showed inhibition of JAK2/STAT3 activation and Bcl-XL expression. There was also increase in expression of caspase-3 and caspase-9 in tumors on treatment with retinoic acid amide. Thus, retinoic acid amide exhibits promising antiproliferative effects against human lung cancer cells in vitro and in vivo and enhances the antiproliferative effect of methotrexate.

  12. The retinaldehyde reductase activity of DHRS3 is reciprocally activated by retinol dehydrogenase 10 to control retinoid homeostasis.

    Science.gov (United States)

    Adams, Mark K; Belyaeva, Olga V; Wu, Lizhi; Kedishvili, Natalia Y

    2014-05-23

    The retinoic acid-inducible dehydrogenase reductase 3 (DHRS3) is thought to function as a retinaldehyde reductase that controls the levels of all-trans-retinaldehyde, the immediate precursor for bioactive all-trans-retinoic acid. However, the weak catalytic activity of DHRS3 and the lack of changes in retinaldehyde conversion to retinol and retinoic acid in the cells overexpressing DHRS3 undermine its role as a physiologically important all-trans-retinaldehyde reductase. This study demonstrates that DHRS3 requires the presence of retinol dehydrogenase 10 (RDH10) to display its full catalytic activity. The RDH10-activated DHRS3 acts as a robust high affinity all-trans-retinaldehyde-specific reductase that effectively converts retinaldehyde back to retinol, decreasing the rate of retinoic acid biosynthesis. In turn, the retinol dehydrogenase activity of RDH10 is reciprocally activated by DHRS3. At E13.5, DHRS3-null embryos have ∼4-fold lower levels of retinol and retinyl esters, but only slightly elevated levels of retinoic acid. The membrane-associated retinaldehyde reductase and retinol dehydrogenase activities are decreased by ∼4- and ∼2-fold, respectively, in Dhrs3(-/-) embryos, and Dhrs3(-/-) mouse embryonic fibroblasts exhibit reduced metabolism of both retinaldehyde and retinol. Neither RDH10 nor DHRS3 has to be itself catalytically active to activate each other. The transcripts encoding DHRS3 and RDH10 are co-localized at least in some tissues during development. The mutually activating interaction between the two related proteins may represent a highly sensitive and conserved mechanism for precise control over the rate of retinoic acid biosynthesis.

  13. In vitro interaction study of retinoic acid isomers with telmisartan and amlodipine by equilibrium dialysis method using UV spectroscopy

    Science.gov (United States)

    Varghese, Susheel John; Johny, Sojimol K.; Paul, David; Ravi, Thengungal Kochupappy

    2011-07-01

    The in vitro protein binding of retinoic acid isomers (isotretinoin and tretinoin) and the antihypertensive drugs (amlodipine and telmisartan) was studied by equilibrium dialysis method. In this study, free fraction of drugs and the % of binding of drugs in the mixture to bovine serum albumin (BSA) were calculated. The influence of retinoic acid isomers on the % of protein binding of telmisartan and amlodipine at physiological pH (7.4) and temperature (37 ± 0.5 °C) was also evaluated. The in vitro displacement interaction study of drugs telmisartan and amlodipine on retinoic acid isomers and also interaction of retinoic acid isomers on telmisartan and amlodipine were carried out.

  14. 丙酸氯倍他索和维甲酸联合应用对小鼠淋巴细胞、人角质形成细胞增殖及其Ⅰ型转谷氨酰胺酶mRNA表达的影响%Pharmacological effects of clobetasol propionate combined with all-trans-retinoic acid on proliferations of mouse lymphocytes and human keratinocytes and on expression of type Ⅰ transglutaminase mRNA of keratinocytes in vitro

    Institute of Scientific and Technical Information of China (English)

    李新宇; 郑家润; 高纪伟; 徐兰芳

    2000-01-01

    目的:研究丙酸氯倍他索(CP)和全反式维甲酸(RA)联合应用(CP+RA)对小鼠淋巴细胞增殖及人角质形成细胞(KC)增殖和Ⅰ型转谷氨酰胺酶(TGase)mRNA表达的影响,以探讨两药合用对有关的抗银屑病药效有无相互影响.方法:体外培养条件下,3H-TdR掺入法和RT-PCR技术.结果与结论:CP+RA合用时RA不影响CP抑制小鼠淋巴细胞增殖的药效,CP也不影响RA下调人KC TGase I mRNA表达的作用,对人KC增殖抑制两药有协同作用.CP+RA合用在发挥各自不同药效的同时,可减少各自的剂量,进而能减少两药各自的副作用.

  15. Effect of all-trans-retinoic acid on α-SMA, Collagen-Ⅰ and HSP47 expressions in TGF-β1-stimulated human lung fibroblasts%全反式维甲酸对HFL-Ⅰ细胞α-平滑肌肌动蛋白、Ⅰ型胶原、热休克蛋白47表达的影响

    Institute of Scientific and Technical Information of China (English)

    刘巨源; 李佳鑫; 海广范; 陈永凤; 夏武; 贾岩龙

    2011-01-01

    目的 研究全反式维甲酸(ATRA)对转化生长因子-β1(TGF-β1)诱导的人胚肺成纤维细胞(HFL-Ⅰ)中α-平滑肌肌动蛋白(α-SMA),Ⅰ型胶原(Collagen-Ⅰ),热休克蛋白47(HSP47) mRNA和蛋白表达的影响.方法 体外培养HFL-Ⅰ细胞,MTT法检测不同浓度TGF-β1和ATRA分别作用3 d对HFL-Ⅰ细胞增殖能力的影响.随后分为6组:对照组、5 μg·L-1 TGF-β1组、10 μmol·L-1 ATRA组、5 μg·L-1 TGF-β1+0.1 μmol·L-1 ATRA组、5 μg·L-1 TGF-β1+1 μmol·L-1 ATRA组、5 μg·L-1 TGF-β1+10 μmol·L-1 ATRA组,RT-PCR和Western blot方法分别检测各实验组细胞中α-SMA,Collagen-Ⅰ,HSP47 mRNA和蛋白的表达.结果 ① MTT法检测结果显示不同浓度的TGF-β1可刺激HFL-Ⅰ细胞增殖,呈浓度依赖性(P<0.05);不同浓度的ATRA对HFL-Ⅰ细胞增殖能力均有明显抑制作用,并随药物浓度的增加而增强(P<0.05).② 5 μg·L-1 TGF-β1诱导后,HFL-Ⅰ细胞中α-SMA,Collagen-I,HSP47 mRNA和蛋白表达均明显上调(P<0.05).③ ATRA以浓度依赖性方式下调经TGF-β1诱导的HFL-Ⅰ细胞中α-SMA,Collagen-I,HSP47 mRNA和蛋白的表达(P<0.05).结论 ATRA能够抑制TGF-β1诱导的HFL-Ⅰ细胞的分化,其作用机制可能与降低Collagen-I、HSP47表达有关.%Aim To investigate the effects of all-transretinoic acid ( ATRA ) on the expression of α-smooth muscle actin( α-SMA ), Collagen-Ⅰ and heat shock protein 47 ( HSP47 ) in the TCF-β1-stimulated human lung fibroblasts ( HFL- Ⅰ ). Methods Firstly, cell proliferation of HFL- Ⅰ was detected by MTT after the cells were treated with different concentrations of TGF β1 and ATRA respectively for 3 days. HFL- Ⅰ cells in vitro were divided into six experimental groups: the control group; 5 μg · L-1 TGF-β1 group; 10 μmol · L-1 ATRA group; 5 μg · L-1 TGF-β1 +0. 1 μmol · L-1 ATRA group; 5 μg · L-1 TCF-β1 +1 μmol · L-1 ATRA group; 5 μg · L-1 TGF-β1 + lOμmol · L-1 ATRA group. Expressions of α-SMA, Collagen- Ⅰ HSP47 were determined through RT-PCR and Western blot. Results Different concentrations of TGF-β1 and ATRA could respectively promote cell proliferation of HFL- Ⅰ in a concentration-dependent manner. Furthermore. in a concentration-dependent manner. ATRA reduced the mRNA and protein expressions of α-SMA. Collagen- Ⅰ and HSP47 which obviously increased in the TGF-β1-stimulated HFL- Ⅰ cells. Conclusions ATRA can inhibit TGF-β1-stimulated differentiation and proliferation of HFL- Ⅰ cells. The mechamsm may be related to the down-regulation of the expression of Collagen- Ⅰ and HSP47.

  16. Direct inhibition of retinoic acid catabolism by fluoxetine.

    Science.gov (United States)

    Hellmann-Regen, Julian; Uhlemann, Ria; Regen, Francesca; Heuser, Isabella; Otte, Christian; Endres, Matthias; Gertz, Karen; Kronenberg, Golo

    2015-09-01

    Recent evidence from animal and human studies suggests neuroprotective effects of the SSRI fluoxetine, e.g., in the aftermath of stroke. The underlying molecular mechanisms remain to be fully defined. Because of its effects on the cytochrome P450 system (CYP450), we hypothesized that neuroprotection by fluoxetine is related to altered metabolism of retinoic acid (RA), whose CYP450-mediated degradation in brain tissue constitutes an important step in the regulation of its site-specific auto- and paracrine actions. Using traditional pharmacological in vitro assays, the effects of fluoxetine on RA degradation were probed in crude synaptosomes from rat brain and human-derived SH-SY5Y cells, and in cultures of neuron-like SH-SY5Y cells. Furthermore, retinoid-dependent effects of fluoxetine on neuronal survival following glutamate exposure were investigated in rat primary neurons cells using specific retinoid receptor antagonists. Experiments revealed dose-dependent inhibition of synaptosomal RA degradation by fluoxetine along with dose-dependent increases in RA levels in cell cultures. Furthermore, fluoxetine's neuroprotective effects against glutamate excitotoxicity in rat primary neurons were demonstrated to partially depend on RA signaling. Taken together, these findings demonstrate for the first time that the potent, pleiotropic antidepressant fluoxetine directly interacts with RA homeostasis in brain tissue, thereby exerting its neuroprotective effects.

  17. Retinoic acid activates two pathways required for meiosis in mice.

    Directory of Open Access Journals (Sweden)

    Jana Koubova

    2014-08-01

    Full Text Available In all sexually reproducing organisms, cells of the germ line must transition from mitosis to meiosis. In mice, retinoic acid (RA, the extrinsic signal for meiotic initiation, activates transcription of Stra8, which is required for meiotic DNA replication and the subsequent processes of meiotic prophase. Here we report that RA also activates transcription of Rec8, which encodes a component of the cohesin complex that accumulates during meiotic S phase, and which is essential for chromosome synapsis and segregation. This RA induction of Rec8 occurs in parallel with the induction of Stra8, and independently of Stra8 function, and it is conserved between the sexes. Further, RA induction of Rec8, like that of Stra8, requires the germ-cell-intrinsic competence factor Dazl. Our findings strengthen the importance of RA and Dazl in the meiotic transition, provide important details about the Stra8 pathway, and open avenues to investigate early meiosis through analysis of Rec8 induction and function.

  18. Retinoic acid from retinal pigment epithelium induces T regulatory cells.

    Science.gov (United States)

    Kawazoe, Yuko; Sugita, Sunao; Keino, Hiroshi; Yamada, Yukiko; Imai, Ayano; Horie, Shintaro; Mochizuki, Manabu

    2012-01-01

    Primary cultured retinal pigment epithelial (RPE) cells can convert T cells into T regulatory cells (Tregs) through inhibitory factor(s) including transforming growth factor β (TGFβ) in vitro. Retinoic acid (RA) enhances induction of CD4(+) Tregs in the presence of TGFβ. We investigated whether RA produced by RPE cells can promote generation of Tregs. We found that in vitro, RA-treated T cells expressed high levels of Foxp3 in the presence of recombinant TGFβ. In GeneChip analysis, cultured RPE cells constitutively expressed RA-associated molecules such as RA-binding proteins, enzymes, and receptors. RPE from normal mice, but not vitamin A-deficient mice, contained significant levels of TGFβ. RPE-induced Tregs from vitamin A-deficient mice failed to suppress activation of target T cells. Only a few Foxp3(+) T cells were found in intraocular cells from vitamin A-deficient experimental autoimmune uveitis (EAU) mice, whereas expression was higher in cells from normal EAU mice. RA receptor antagonist-pretreated or RA-binding protein-siRNA-transfected RPE cells failed to convert CD4(+) T cells into Tregs. Our data support the hypothesis that RPE cells produce RA, thereby enabling bystander T cells to be converted into Tregs through TGFβ promotion, which can then participate in the establishment of immune tolerance in the eye.

  19. Retinoic acid signaling and the evolution of chordates

    Directory of Open Access Journals (Sweden)

    2006-04-01

    Full Text Available In chordates, which comprise urochordates, cephalochordates and vertebrates, the vitamin A-derived morphogen retinoic acid (RA has a pivotal role during development. Altering levels of endogenous RA signaling during early embryology leads to severe malformations, mainly due to incorrect positional codes specifying the embryonic anteroposterior body axis. In this review, we present our current understanding of the RA signaling pathway and its roles during chordate development. In particular, we focus on the conserved roles of RA and its downstream mediators, the Hox genes, in conveying positional patterning information to different embryonic tissues, such as the endoderm and the central nervous system. We find that some of the control mechanisms governing RA-mediated patterning are well conserved between vertebrates and invertebrate chordates, such as the cephalochordate amphioxus. In contrast, outside the chordates, evidence for roles of RA signaling is scarce and the evolutionary origin of the RA pathway itself thus remains elusive. In sum, to fully understand the evolutionary history of the RA pathway, future research should focus on identification and study of components of the RA signaling cascade in non-chordate deuterostomes (such as hemichordates and echinoderms and other invertebrates, such as insects, mollusks and cnidarians.

  20. Early retinoic acid deprivation in developing zebrafish results in microphthalmia.

    Science.gov (United States)

    Le, Hong-Gam T; Dowling, John E; Cameron, D Joshua

    2012-09-01

    Vitamin A deficiency causes impaired vision and blindness in millions of children around the world. Previous studies in zebrafish have demonstrated that retinoic acid (RA), the acid form of vitamin A, plays a vital role in early eye development. The objective of this study was to describe the effects of early RA deficiency by treating zebrafish with diethylaminobenzaldehyde (DEAB), a potent inhibitor of the enzyme retinaldehyde dehydrogenase (RALDH) that converts retinal to RA. Zebrafish embryos were treated for 2 h beginning at 9 h postfertilization. Gross morphology and retinal development were examined at regular intervals for 5 days after treatment. The optokinetic reflex (OKR) test, visual background adaptation (VBA) test, and the electroretinogram (ERG) were performed to assess visual function and behavior. Early treatment of zebrafish embryos with 100 μM DEAB (9 h) resulted in reduced eye size, and this microphthalmia persisted through larval development. Retinal histology revealed that DEAB eyes had significant developmental abnormalities but had relatively normal retinal lamination by 5.5 days postfertilization. However, the fish showed neither an OKR nor a VBA response. Further, the retina did not respond to light as measured by the ERG. We conclude that early deficiency of RA during eye development causes microphthalmia as well as other visual defects, and that timing of the RA deficiency is critical to the developmental outcome.

  1. Protective Effect of Ocimum basilicum Essential Oil Against Acetic Acid-Induced Colitis in Rats.

    Science.gov (United States)

    Rashidian, Amir; Roohi, Parnia; Mehrzadi, Saeed; Ghannadi, Ali Reza; Minaiyan, Mohsen

    2016-10-01

    Ocimum basilicum L has been traditionally used for the treatment of inflammatory bowel disease in Iran. This study investigates the ameliorative effect of Ocimum basilicum essential oil on an acetic acid-induced colitis model in rats. Ocimum basilicum essential oil with 2 doses (200 and 400 μL/kg) significantly ameliorated wet weight/length ratio of colonic tissue compared to the control group. Higher doses of essential oil (200 and 400 μL/kg) significantly reduced ulcer severity, ulcer area, and ulcer index. On the other hand, histological examination revealed the diminution of total colitis index as a marker for inflammatory cell infiltration in the colonic segments of rats treated with Ocimum basilicum essential oil (200 and 400 μL/kg). The increased level of myeloperoxidase was significantly decreased after the treatment with the essential oil (200 and 400 μL/kg). These results suggest that Ocimum basilicum exhibits protective effect against acetic acid-induced colitis.

  2. The Ayurvedic drug, Ksheerabala, ameliorates quinolinic acid-induced oxidative stress in rat brain

    OpenAIRE

    Swathy, S. S.; Indira, M.

    2010-01-01

    One of the mechanisms of neurotoxicity is the induction of oxidative stress. There is hardly any cure for neurotoxicity in modern medicine, whereas many drugs in Ayurveda possess neuroprotective effects; however, there is no scientific validation for these drugs. Ksheerabala is an ayurvedic drug which is used to treat central nervous system disorders, arthritis, and insomnia. The aim of our study was to evaluate the effect of Ksheerabala on quinolinic acid-induced toxicity in rat brain. The o...

  3. Protective effect of hispidulin on kainic acid-induced seizures and neurotoxicity in rats.

    Science.gov (United States)

    Lin, Tzu Yu; Lu, Cheng Wei; Wang, Su Jane; Huang, Shu Kuei

    2015-05-15

    Hispidulin is a flavonoid compound which is an active ingredient in a number of traditional Chinese medicinal herbs, and it has been reported to inhibit glutamate release. The purpose of this study was to investigate whether hispidulin protects against seizures induced by kainic acid, a glutamate analog with excitotoxic properties. The results indicated that intraperitoneally administering hispidulin (10 or 50mg/kg) to rats 30 min before intraperitoneally injecting kainic acid (15 mg/kg) increased seizure latency and decreased seizure score. In addition, hispidulin substantially attenuated kainic acid-induced hippocampal neuronal cell death, and this protective effect was accompanied by the suppression of microglial activation and the production of proinflammatory cytokines such as interleukin-1β, interleukin-6, and tumor necrosis factor-α in the hippocampus. Moreover, hispidulin reduced kainic acid-induced c-Fos expression and the activation of mitogen-activated protein kinases in the hippocampus. These data suggest that hispidulin has considerable antiepileptic, neuroprotective, and antiinflammatory effects on kainic acid-induced seizures in rats.

  4. Autophagy Protects against Palmitic Acid-Induced Apoptosis in Podocytes in vitro.

    Science.gov (United States)

    Jiang, Xu-Shun; Chen, Xue-Mei; Wan, Jiang-Min; Gui, Hai-Bo; Ruan, Xiong-Zhong; Du, Xiao-Gang

    2017-02-22

    Autophagy is a highly conserved degradation process that is involved in the clearance of proteins and damaged organelles to maintain intracellular homeostasis and cell integrity. Type 2 diabetes is often accompanied by dyslipidemia with elevated levels of free fatty acids (FFAs). Podocytes, as an important component of the filtration barrier, are susceptible to lipid disorders. The loss of podocytes causes proteinuria, which is involved in the pathogenesis of diabetic nephropathy. In the present study, we demonstrated that palmitic acid (PA) promoted autophagy in podocytes. We further found that PA increased the production of reactive oxygen species (ROS) in podocytes and that NAC (N-acetyl-cysteine), a potent antioxidant, significantly eliminated the excessive ROS and suppressed autophagy, indicating that the increased generation of ROS was associated with the palmitic acid-induced autophagy in podocytes. Moreover, we also found that PA stimulation decreased the mitochondrial membrane potential in podocytes and induced podocyte apoptosis, while the inhibition of autophagy by chloroquine (CQ) enhanced palmitic acid-induced apoptosis accompanied by increased ROS generation, and the stimulation of autophagy by rapamycin (Rap) remarkably suppressed palmitic acid-induced ROS generation and apoptosis. Taken together, these in vitro findings suggest that PA-induced autophagy in podocytes is mediated by ROS production and that autophagy plays a protective role against PA-induced podocyte apoptosis.

  5. Minocycline ameliorates prenatal valproic acid induced autistic behaviour, biochemistry and blood brain barrier impairments in rats.

    Science.gov (United States)

    Kumar, Hariom; Sharma, Bhupesh

    2016-01-01

    Autism is a neurodevelopment disorder. One percent worldwide population suffers with autism and males suffer more than females. Microglia plays an important role in neurodevelopment, neuropsychiatric and neurodegenerative disorders. The present study has been designed to investigate the role of minocycline in prenatal valproic acid induced autism in rats. Animals with prenatal valproic acid have reduced social interaction (three chamber social behaviour apparatus), spontaneous alteration (Y-Maze), exploratory activity (Hole board test), intestinal motility, serotonin levels (both in prefrontal cortex and ileum) and prefrontal cortex mitochondrial complex activity (complexes I, II, IV). Furthermore, prenatal valproic acid treated animals have shown an increase in locomotion (actophotometer), anxiety (elevated plus maze), brain oxidative stress (thiobarbituric acid reactive species, glutathione, catalase), nitrosative stress (nitrite/nitrate), inflammation (both in brain and ileum myeloperoxidase activity), calcium and blood brain barrier permeability. Treatment with minocycline significantly attenuated prenatal valproic acid induced reduction in social interaction, spontaneous alteration, exploratory activity intestinal motility, serotonin levels and prefrontal cortex mitochondrial complex activity. Furthermore, minocycline has also attenuated prenatal valproic acid induced increase in locomotion, anxiety, brain oxidative and nitrosative stress, inflammation, calcium and blood brain barrier permeability. Thus, it may be concluded that prenatal valproic acid has induced autistic behaviour, biochemistry and blood brain barrier impairment in animals, which were significantly attenuated by minocycline. Minocycline should be explored further for its therapeutic benefits in autism.

  6. Autophagy Protects against Palmitic Acid-Induced Apoptosis in Podocytes in vitro

    Science.gov (United States)

    Jiang, Xu-shun; Chen, Xue-mei; Wan, Jiang-min; Gui, Hai-bo; Ruan, Xiong-zhong; Du, Xiao-gang

    2017-01-01

    Autophagy is a highly conserved degradation process that is involved in the clearance of proteins and damaged organelles to maintain intracellular homeostasis and cell integrity. Type 2 diabetes is often accompanied by dyslipidemia with elevated levels of free fatty acids (FFAs). Podocytes, as an important component of the filtration barrier, are susceptible to lipid disorders. The loss of podocytes causes proteinuria, which is involved in the pathogenesis of diabetic nephropathy. In the present study, we demonstrated that palmitic acid (PA) promoted autophagy in podocytes. We further found that PA increased the production of reactive oxygen species (ROS) in podocytes and that NAC (N-acetyl-cysteine), a potent antioxidant, significantly eliminated the excessive ROS and suppressed autophagy, indicating that the increased generation of ROS was associated with the palmitic acid-induced autophagy in podocytes. Moreover, we also found that PA stimulation decreased the mitochondrial membrane potential in podocytes and induced podocyte apoptosis, while the inhibition of autophagy by chloroquine (CQ) enhanced palmitic acid-induced apoptosis accompanied by increased ROS generation, and the stimulation of autophagy by rapamycin (Rap) remarkably suppressed palmitic acid-induced ROS generation and apoptosis. Taken together, these in vitro findings suggest that PA-induced autophagy in podocytes is mediated by ROS production and that autophagy plays a protective role against PA-induced podocyte apoptosis. PMID:28225005

  7. Depletion of retinoic acid receptors initiates a novel positive feedback mechanism that promotes teratogenic increases in retinoic acid.

    Directory of Open Access Journals (Sweden)

    Enrico D'Aniello

    Full Text Available Normal embryonic development and tissue homeostasis require precise levels of retinoic acid (RA signaling. Despite the importance of appropriate embryonic RA signaling levels, the mechanisms underlying congenital defects due to perturbations of RA signaling are not completely understood. Here, we report that zebrafish embryos deficient for RA receptor αb1 (RARαb1, a conserved RAR splice variant, have enlarged hearts with increased cardiomyocyte (CM specification, which are surprisingly the consequence of increased RA signaling. Importantly, depletion of RARαb2 or concurrent depletion of RARαb1 and RARαb2 also results in increased RA signaling, suggesting this effect is a broader consequence of RAR depletion. Concurrent depletion of RARαb1 and Cyp26a1, an enzyme that facilitates degradation of RA, and employment of a novel transgenic RA sensor line support the hypothesis that the increases in RA signaling in RAR deficient embryos are the result of increased embryonic RA coupled with compensatory RAR expression. Our results support an intriguing novel mechanism by which depletion of RARs elicits a previously unrecognized positive feedback loop that can result in developmental defects due to teratogenic increases in embryonic RA.

  8. Isomerization of all-(E)-Retinoic Acid Mediated by Carbodiimide Activation - Synthesis of ATRA Ether Lipid Conjugates

    DEFF Research Database (Denmark)

    Christensen, Mikkel Stochkendahl; Pedersen, Palle Jacob; Andresen, Thomas Lars;

    2010-01-01

    Treatment of the lysolipid 1-O-hexadecyl-sn-phosphatidylcholine with all-(E)-retinoic acid, DCC and DMAP resulted in poor acylation and caused (Z)/(E) isomerization of the alpha-beta double bond. In the presence of a proton source, the carbodiimide-activated all-(E)-retinoic acid undergoes fast i...

  9. Retinoic acid deficiency alters second heart field formation

    Science.gov (United States)

    Ryckebusch, Lucile; Wang, Zengxin; Bertrand, Nicolas; Lin, Song-Chang; Chi, Xuan; Schwartz, Robert; Zaffran, Stéphane; Niederreither, Karen

    2008-01-01

    Retinoic acid (RA), the active derivative of vitamin A, has been implicated in various steps of cardiovascular development. The retinaldehyde dehydrogenase 2 (RALDH2) enzyme catalyzes the second oxidative step in RA biosynthesis and its loss of function creates a severe embryonic RA deficiency. Raldh2−/− knockout embryos fail to undergo heart looping and have impaired atrial and sinus venosus development. To understand the mechanism(s) producing these changes, we examined the contribution of the second heart field (SHF) to pharyngeal mesoderm, atria, and outflow tract in Raldh2−/− embryos. RA deficiency alters SHF gene expression in two ways. First, Raldh2−/− embryos exhibited a posterior expansion of anterior markers of the SHF, including Tbx1, Fgf8, and the Mlc1v-nlacZ-24/Fgf10 reporter transgene as well as of Islet1. This occurred at early somite stages, when cardiac defects became irreversible in an avian vitamin A-deficiency model, indicating that endogenous RA is required to restrict the SHF posteriorly. Explant studies showed that this expanded progenitor population cannot differentiate properly. Second, RA up-regulated cardiac Bmp expression levels at the looping stage. The contribution of the SHF to both inflow and outflow poles was perturbed under RA deficiency, creating a disorganization of the heart tube. We also investigated genetic cross-talk between Nkx2.5 and RA signaling by generating double mutant mice. Strikingly, Nkx2.5 deficiency was able to rescue molecular defects in the posterior region of the Raldh2−/− mutant heart, in a gene dosage-dependent manner. PMID:18287057

  10. Retinoic Acid Excess Impairs Amelogenesis Inducing Enamel Defects

    Science.gov (United States)

    Morkmued, Supawich; Laugel-Haushalter, Virginie; Mathieu, Eric; Schuhbaur, Brigitte; Hemmerlé, Joseph; Dollé, Pascal; Bloch-Zupan, Agnès; Niederreither, Karen

    2017-01-01

    Abnormalities of enamel matrix proteins deposition, mineralization, or degradation during tooth development are responsible for a spectrum of either genetic diseases termed Amelogenesis imperfecta or acquired enamel defects. To assess if environmental/nutritional factors can exacerbate enamel defects, we investigated the role of the active form of vitamin A, retinoic acid (RA). Robust expression of RA-degrading enzymes Cyp26b1 and Cyp26c1 in developing murine teeth suggested RA excess would reduce tooth hard tissue mineralization, adversely affecting enamel. We employed a protocol where RA was supplied to pregnant mice as a food supplement, at a concentration estimated to result in moderate elevations in serum RA levels. This supplementation led to severe enamel defects in adult mice born from pregnant dams, with most severe alterations observed for treatments from embryonic day (E)12.5 to E16.5. We identified the enamel matrix proteins enamelin (Enam), ameloblastin (Ambn), and odontogenic ameloblast-associated protein (Odam) as target genes affected by excess RA, exhibiting mRNA reductions of over 20-fold in lower incisors at E16.5. RA treatments also affected bone formation, reducing mineralization. Accordingly, craniofacial ossification was drastically reduced after 2 days of treatment (E14.5). Massive RNA-sequencing (RNA-seq) was performed on E14.5 and E16.5 lower incisors. Reductions in Runx2 (a key transcriptional regulator of bone and enamel differentiation) and its targets were observed at E14.5 in RA-exposed embryos. RNA-seq analysis further indicated that bone growth factors, extracellular matrix, and calcium homeostasis were perturbed. Genes mutated in human AI (ENAM, AMBN, AMELX, AMTN, KLK4) were reduced in expression at E16.5. Our observations support a model in which elevated RA signaling at fetal stages affects dental cell lineages. Thereafter enamel protein production is impaired, leading to permanent enamel alterations. PMID:28111553

  11. Activation of retinoic acid receptor alpha is sufficient for full induction of retinoid responses in SK-BR-3 and T47D human breast cancer cells.

    Science.gov (United States)

    Schneider, S M; Offterdinger, M; Huber, H; Grunt, T W

    2000-10-01

    Retinoid signaling via retinoic acid (RA) and retinoid X receptors (RARs and RXRs) regulates mammary epithelial cell growth and differentiation. Loss of RAR-beta might represent an early event during breast carcinogenesis. Higher differentiated, estrogen-dependent, estrogen receptor (ER)-positive (ER+) mammary carcinoma cells have been found to contain relatively high levels of RAR-alpha and to be responsive to retinoids, whereas most undifferentiated, estrogen-independent, ER-negative (ER-) cells are characterized by low RAR-alpha expression and by retinoid resistance. In contrast, RAR-gamma is detectable at equal levels in both ER+ and ER- cells. In the present investigation, we directly examined the relative contribution of the distinct retinoid receptors to the retinoid response of breast cancer cells by comparing the effects of low concentrations of specific retinoids, which selectively activate individual receptor subtypes, on growth, cell cycle distribution, apoptosis, and on the autoregulation of RAR-alpha and RAR-gamma in ER- SK-BR-3 and ER+ T47D breast cancer cells. In vitro growth activity was determined by using a colorimetric cell viability assay and analysis of cell cycle distribution, and apoptosis was performed by flow cytometry of propidium iodide-stained or fluorescent Annexin V-labeled cells, respectively, whereas expression of RAR-alpha and RAR-gamma was determined by Northern blotting. Both cell lines are retinoid sensitive and express high amounts of RAR-alpha, RAR-gamma, and RXR-alpha. RAR-alpha-selective compounds (AM80 and AM580) inhibit cell growth, induce G1 arrest, stimulate apoptosis, and up-regulate RAR-alpha and RAR-gamma mRNA as efficiently as RAR/RXR-pan-reactive (9-cis RA) and RAR-pan-reactive retinoids (all-trans RA, TTNPB). Remarkably, an RAR-alpha antagonist (Ro 41-5253) not only blocks the RAR-alpha-selective agonists but also the pan-reactive compounds. In contrast, RAR-13-selective (CD417), RAR-gamma-selective (CD437/AHPN

  12. Potentiation of the teratogenic effects induced by coadministration of retinoic acid or phytanic acid/phytol with synthetic retinoid receptor ligands.

    Science.gov (United States)

    Elmazar, M M A; Nau, H

    2004-11-01

    Previous studies in our laboratory identified retinoid-induced defects that are mediated by RAR-RXR heterodimerization using interaction of synthetic ligands selective for the retinoid receptors RAR and RXR in mice (Elmazar et al. 1997, Toxicol Appl Pharmacol 146:21-28; Elmazar et al. 2001, Toxicol Appl Pharmacol 170:2-9; Nau and Elmazar 1999, Handbook of experimental pharmacology, vol 139, Retinoids, Springer-Verlag, pp 465-487). The present study was designed to investigate whether these RAR-RXR heterodimer-mediated defects can be also induced by interactions of natural and synthetic ligands for retinoid receptors. A non-teratogenic dose of the natural RXR agonist phytanic acid (100 mg/kg orally) or its precursor phytol (500 mg/kg orally) was coadministered with a synthetic RARalpha-agonist (Am580; 5 mg/kg orally) to NMRI mice on day 8.25 of gestation (GD8.25). Furthermore, a non-teratogenic dose of the synthetic RXR agonist LGD1069 (20 mg/kg orally) was also coadministered with the natural RAR agonist, all- trans-retinoic acid (atRA, 20 mg/kg orally) or its precursor retinol (ROH, 50 mg/kg orally) to NMRI mice on GD8.25. The teratogenic outcome was scored in day-18 fetuses. The incidence of Am580-induced resorptions, spina bifida aperta, micrognathia, anotia, kidney hypoplasia, dilated bladder, undescended testis, atresia ani, short and absent tail, fused ribs and fetal weight retardation were potentiated by coadministration of phytanic acid or its precursor phytol. Am580-induced exencephaly and cleft palate, which were not potentiated by coadministration with the synthetic RXR agonists, were also not potentiated by coadministration with either phytanic acid or its precursor phytol. LGD1069 potentiated atRA- and ROH-induced resorption, exencephaly, spina bifida, aperta, ear anotia and microtia, macroglossia, kidney hypoplasia, undescended testis, atresia ani, tail defects and fetal weight retardation, but not cleft palate. These results suggest that synergistic

  13. A role for sodium and chloride in kainic acid-induced beading of inhibitory interneuron dendrites.

    Science.gov (United States)

    Al-Noori, S; Swann, J W

    2000-01-01

    Excitotoxic injury of the dendrites of inhibitory interneurons could lead to decreases in their synaptic activation and explain subsequent local circuit hyperexcitability and epilepsy. A hallmark of dendrotoxicity, at least in principal neurons of the hippocampus and cortex, is focal or varicose swellings of dendritic arbors. In experiments reported here, transient (1h) exposure of hippocampal explant cultures to kainic acid produced marked focal swellings of the dendrites of parvalbumin-immunoreactive pyramidal basket cells in a highly reproducible and dose-dependent manner. At 5mM kainic acid, more than half of the immunopositive apical dendrites in area CA(1) had a beaded appearance. However, the somal volumes of these cells were unaltered by the same treatment. The presence of focal swellings was reversible with kainate washout and was not accompanied by interneuronal cell death. In contrast, exposure to much higher concentrations (300mM) of kainic acid resulted in the total loss of parvalbumin-positive interneurons from explants. Surprisingly, kainic acid-induced dendritic beading does not appear to be mediated by extracellular calcium. Beading was unaltered in the presence of N-methyl-D-aspartate receptor antagonists, the L-type calcium channel antagonist, nimodipine, cadmium, or by removing extracellular calcium. However, blockade of voltage-gated sodium channels by either tetrodotoxin or lidocaine abolished dendritic beading, while the activation of existing voltage-gated sodium channels by veratridine mimicked the kainic acid-induced dendritic beading. Finally, the removal of extracellular chloride prevented the kainic acid-induced dendritic beading.Thus, we suggest that the movement of Na(+) and Cl(-), rather than Ca(2+), into cells underlies the focal swellings of interneuron dendrites in hippocampus.

  14. Calcium Uptake via Mitochondrial Uniporter Contributes to Palmitic Acid-induced Apoptosis in Mouse Podocytes.

    Science.gov (United States)

    Yuan, Zeting; Cao, Aili; Liu, Hua; Guo, Henjiang; Zang, Yingjun; Wang, Yi; Wang, Yunman; Wang, Hao; Yin, Peihao; Peng, Wen

    2017-02-09

    Podocytes are component cells of the glomerular filtration barrier, and their loss by apoptosis is the main cause of proteinuria that leads to diabetic nephropathy (DN). Therefore, insights into podocyte apoptosis mechanism would allow a better understanding of DN pathogenesis and thus help develop adequate therapeutic strategies. Here, we investigated the molecular mechanism of palmitic acid-inhibited cell death in mouse podocytes, and found that palmitic acid increased cell death in a dose- and time-dependent manner. Palmitic acid induces apoptosis in podocytes through up-regulation of cytosolic and mitochondrial Ca(2+) , mitochondrial membrane potential (MMP), cytochrome c release and depletion of endoplasmic reticulum (ER) Ca(2+) , The intracellular calcium chelator, 1,2-bis (2-aminophenoxy) ethane-N,N,N, N'-tetraacetic acid tetrakis acetoxymethyl ester (BAPTA-AM), partially prevented this up-regulation whereas 2-aminoethoxydiphenyl borate (2-APB), an inositol 1,4,5-triphosphate receptor (IP3R) inhibitor; dantrolene, a ryanodine receptor (RyR) inhibitor; and 4,4'-diisothiocyanatostibene-2,2'-disulfonic acid (DIDS), an anion exchange inhibitor, had no effect. Interestingly, ruthenium red and Ru360, both inhibitors of the mitochondrial Ca(2+) uniporter (MCU), blocked palmitic acid-induced mitochondrial Ca(2+) elevation, cytochrome c release from mitochondria to cytosol, and apoptosis. siRNA to MCU markedly reduced curcumin-induced apoptosis. These data indicate that Ca(2+) uptake via mitochondrial uniporter contributes to palmitic acid-induced apoptosis in mouse podocytes. This article is protected by copyright. All rights reserved.

  15. Benfotiamine attenuates nicotine and uric acid-induced vascular endothelial dysfunction in the rat.

    Science.gov (United States)

    Balakumar, Pitchai; Sharma, Ramica; Singh, Manjeet

    2008-01-01

    The study has been designed to investigate the effect of benfotiamine, a thiamine derivative, in nicotine and uric acid-induced vascular endothelial dysfunction (VED) in rats. Nicotine (2 mg kg(-1)day(-1), i.p., 4 weeks) and uric acid (150 mg kg(-1)day(-1), i.p., 3 weeks) were administered to produce VED in rats. The development of VED was assessed by employing isolated aortic ring preparation and estimating serum and aortic concentration of nitrite/nitrate. Further, the integrity of vascular endothelium was assessed using the scanning electron microscopy (SEM) of thoracic aorta. Moreover, the oxidative stress was assessed by estimating serum thiobarbituric acid reactive substances (TBARS) and aortic superoxide anion generation. The administration of nicotine and uric acid produced VED by impairing the integrity of vascular endothelium and subsequently decreasing serum and aortic concentration of nitrite/nitrate and attenuating acetylcholine-induced endothelium dependent relaxation. Further, nicotine and uric acid produced oxidative stress, which was assessed in terms of increase in serum TBARS and aortic superoxide generation. However, treatment with benfotiamine (70 mg kg(-1)day(-1), p.o.) or atorvastatin (30 mg kg(-1)day(-1) p.o., a standard agent) markedly prevented nicotine and uric acid-induced VED and oxidative stress by improving the integrity of vascular endothelium, increasing the concentration of serum and aortic nitrite/nitrate, enhancing the acetylcholine-induced endothelium dependent relaxation and decreasing serum TBARS and aortic superoxide anion generation. Thus, it may be concluded that benfotiamine reduces the oxidative stress and consequently improves the integrity of vascular endothelium and enhances the generation of nitric oxide to prevent nicotine and uric acid-induced experimental VED.

  16. Clavulanic acid induces penile erection and yawning in male rats: comparison with apomorphine.

    Science.gov (United States)

    Sanna, Fabrizio; Melis, Maria Rosaria; Angioni, Laura; Argiolas, Antonio

    2013-02-01

    The beta-lactamase inhibitor clavulanic acid induced penile erection and yawning in a dose dependent manner when given intraperitoneally (IP, 0.05-5mg/kg), perorally (OS, 0.1-5mg/kg) and intracereboventricularly (ICV, 0.01-5 μg/rat) to male rats. The effect resembles that of the dopamine receptor agonist apomorphine given subcutaneously (SC) (0.02-0.25mg/kg), although the responses of the latter followed a U inverted dose-response curve, disappearing at doses higher than 0.1mg/kg. Clavulanic acid responses were reduced by about 55% by haloperidol, a dopamine D2 receptor antagonist (0.1mg/kg IP), and by d(CH(2))(5)Tyr(Me)(2)-Orn(8)-vasotocin, an oxytocin receptor antagonist (2 μg/rat ICV), both given 15 min before clavulanic acid. A higher reduction of clavulanic acid responses (more than 80%) was also found with morphine, an opioid receptor agonist (5mg/kg IP), and with mianserin, a serotonin 5HT(2c) receptor antagonist (0.2mg/kg SC). In contrast, no reduction was found with naloxone, an opioid receptor antagonist (1mg/kg IP). The ability of haloperidol, d(CH(2))(5)Tyr(Me)(2)-Orn(8)-vasotocin and morphine to reduce clavulanic acid induced penile erection and yawning suggests that clavulanic acid induces these responses, at least in part, by increasing central dopaminergic neurotransmission. Dopamine in turn activates oxytocinergic neurotransmission and centrally released oxytocin induces penile erection and yawning. However, since both penile erection and yawning episodes were reduced not only by the blockade of central dopamine and oxytocin receptors and by the stimulation of opioid receptors, which inhibits oxytocinergic neurotransmission, but also by mianserin, an increase of central serotonin neurotransmission is also likely to participate in these clavulanic acid responses.

  17. Retinoic acid and Cyp26b1 are critical regulators of osteogenesis in the axial skeleton

    NARCIS (Netherlands)

    Spoorendonk, K.M.; Peterson-Maduro, J.; Renn, J.; Trowe, T.; Kranenbarg, S.; Winkler, C.; Schulte-Merker, S.

    2008-01-01

    Retinoic acid (RA) plays important roles in diverse biological processes ranging from germ cell specification to limb patterning. RA ultimately exerts its effect in the nucleus, but how RA levels are being generated and maintained locally is less clear. Here, we have analyzed the zebrafish stockstei

  18. Retinoic acid and Cyp26b1 are critical regulators of osteogenesis in the axial skeleton.

    NARCIS (Netherlands)

    Spoorendonk, K.M.; Peterson-Maduro, J.; Renn, J.; Trowe, T.; Kranenbarg, S.; Winkler, C.; Schulte-Merker, S.

    2008-01-01

    Retinoic acid (RA) plays important roles in diverse biological processes ranging from germ cell specification to limb patterning. RA ultimately exerts its effect in the nucleus, but how RA levels are being generated and maintained locally is less clear. Here, we have analyzed the zebrafish stockstei

  19. NF1 Is a Tumor Suppressor in Neuroblastoma that Determines Retinoic Acid Response and Disease Outcome

    NARCIS (Netherlands)

    M. Hölzel; S. Huang; J. Koster; I. Ora; A. Lakeman; H. Caron; W. Nijkamp; J. Xie; T. Callens; S. Asgharzadeh; R.C. Seeger; L. Messiaen; R. Versteeg; R. Bernards

    2010-01-01

    Retinoic acid (RA) induces differentiation of neuroblastoma cells in vitro and is used with variable success to treat aggressive forms of this disease. This variability in clinical response to RA is enigmatic, as no mutations in components of the RA signaling cascade have been found. Using a large-s

  20. Study on the Structure of Supramolecular Inclusion Complex of b-Cyclodextrin with Retinoic Acid

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Inclusion compound of retinoic acid with b-cyclodextrin was prepared by coprecipitating method, the structure of resulting product was studied by elemental analysis, differential scanning caloriemetry(DSC) analysis, FT-IR spectroscopy and X-ray diffractometry, and the formed supramolecule self-assembles in aqueous solution according to molar ratio 2:1 of host-guest.

  1. Role of hepatocyte S6K1 in palmitic acid-induced endoplasmic reticulum stress, lipotoxicity, insulin resistance and in oleic acid-induced protection.

    Science.gov (United States)

    Pardo, Virginia; González-Rodríguez, Águeda; Muntané, Jordi; Kozma, Sara C; Valverde, Ángela M

    2015-06-01

    The excess of saturated free fatty acids, such as palmitic acid, that induces lipotoxicity in hepatocytes, has been implicated in the development of non-alcoholic fatty liver disease also associated with insulin resistance. By contrast, oleic acid, a monounsaturated fatty acid, attenuates the effects of palmitic acid. We evaluated whether palmitic acid is directly associated with both insulin resistance and lipoapoptosis in mouse and human hepatocytes and the impact of oleic acid in the molecular mechanisms that mediate both processes. In human and mouse hepatocytes palmitic acid at a lipotoxic concentration triggered early activation of endoplasmic reticulum (ER) stress-related kinases, induced the apoptotic transcription factor CHOP, activated caspase 3 and increased the percentage of apoptotic cells. These effects concurred with decreased IR/IRS1/Akt insulin pathway. Oleic acid suppressed the toxic effects of palmitic acid on ER stress activation, lipoapoptosis and insulin resistance. Besides, oleic acid suppressed palmitic acid-induced activation of S6K1. This protection was mimicked by pharmacological or genetic inhibition of S6K1 in hepatocytes. In conclusion, this is the first study highlighting the activation of S6K1 by palmitic acid as a common and novel mechanism by which its inhibition by oleic acid prevents ER stress, lipoapoptosis and insulin resistance in hepatocytes.

  2. Molecular cloning and analysis of functional cDNA and genomic clones encoding bovine cellular retinoic acid-binding protein.

    OpenAIRE

    Shubeita, H E; Sambrook, J F; McCormick, A M

    1987-01-01

    A recombinant cDNA clone, pCRABP-HS1, encoding cellular retinoic acid-binding protein was isolated from a bovine adrenal cDNA library. COS-7 cells transfected with pCRABP-HS1 produced a biologically active retinoic acid-binding protein molecule of the expected molecular mass (15.5 kDa). RNA blot hybridization analysis using pCRABP-HS1 as a probe revealed a single 1050-nucleotide mRNA species in bovine adrenal, uterus, and testis, tissues that contain the highest levels of retinoic acid-bindin...

  3. Predicting, Monitoring, and Managing Hypercalcemia Secondary to 13-Cis-Retinoic Acid Therapy in Children With High-risk Neuroblastoma.

    Science.gov (United States)

    Chen, Suet Ching; Murphy, Dermot; Sastry, Jairam; Shaikh, Mohamad G

    2015-08-01

    13-cis-retinoic acid is an established component of treatment for children with high-risk neuroblastoma. However, significant hypercalcemia is increasingly recognized as a potentially life-threatening dosage-related side effect. We present 2 patients with significant hypercalcemia secondary to 13-cis-retinoic acid and their management, and identified the predictive factors for susceptibility to hypercalcemia. Assessing glomerular filtration rate and concomitant medication help predict individual susceptibility to hypercalcemia. Calcium levels should be monitored at days 1, 7, and 14 of each course of retinoic acid. An algorithm for the management of hypercalcemia during the affected and subsequent cycles of retinoid therapy is proposed.

  4. Obestatin Accelerates the Healing of Acetic Acid-Induced Colitis in Rats.

    Science.gov (United States)

    Matuszyk, Aleksandra; Ceranowicz, Piotr; Warzecha, Zygmunt; Cieszkowski, Jakub; Bonior, Joanna; Jaworek, Jolanta; Kuśnierz-Cabala, Beata; Konturek, Peter; Ambroży, Tadeusz; Dembiński, Artur

    2016-01-01

    Obestatin, a 23-amino acid peptide derived from the proghrelin, has been shown to exhibit some protective and therapeutic effects in the gut. The aim of present study was to determine the effect of obestatin administration on the course of acetic acid-induced colitis in rats. Materials and Methods. Studies have been performed on male Wistar rats. Colitis was induced by a rectal enema with 3.5% acetic acid solution. Obestatin was administered intraperitoneally twice a day at a dose of 8 nmol/kg, starting 24 h after the induction of colitis. Seven or 14 days after the induction of colitis, the healing rate of the colon was evaluated. Results. Treatment with obestatin after induction of colitis accelerated the healing of colonic wall damage and this effect was associated with a decrease in the colitis-evoked increase in mucosal activity of myeloperoxidase and content of interleukin-1β. Moreover, obestatin administration significantly reversed the colitis-evoked decrease in mucosal blood flow and DNA synthesis. Conclusion. Administration of exogenous obestatin exhibits therapeutic effects in the course of acetic acid-induced colitis and this effect is related, at least in part, to the obestatin-evoked anti-inflammatory effect, an improvement of local blood flow, and an increase in cell proliferation in colonic mucosa.

  5. Exogenous Ghrelin Accelerates the Healing of Acetic Acid-Induced Colitis in Rats

    Directory of Open Access Journals (Sweden)

    Aleksandra Matuszyk

    2016-09-01

    Full Text Available Previous studies have shown that ghrelin reduces colonic inflammation induced by trinitrobenzene sulfonic acid and dextran sodium sulfate. In the present study we determined the effect of treatment with ghrelin on the course of acetic acid-induced colitis in rats. Rectal administration of 3% acetic acid solution led to induction of colitis in all animals. Damage of the colonic wall was accompanied by an increase in mucosal concentration of pro-inflammatory interleukin-1β (IL-1β and tumor necrosis factor-α (TNF-α, as well mucosal activity of myeloperoxidase. Moreover, induction of colitis led to a reduction in colonic blood flow and DNA synthesis. Administration of ghrelin after induction of colitis led to faster regeneration of the colonic wall and reduction in colonic levels of IL-1β, TNF-α, and myeloperoxidase. In addition, treatment with ghrelin improved mucosal DNA synthesis and blood flow. Our study disclosed that ghrelin exhibits a strong anti-inflammatory and healing effect in acetic acid-induced colitis. Our current observation in association with previous findings that ghrelin exhibits curative effect in trinitrobenzene sulfonic acid- and dextran sodium sulfate-induced colitis suggest that therapeutic effect of ghrelin in the colon is universal and independent of the primary cause of colitis.

  6. Comparative neuroprotective profile of statins in quinolinic acid induced neurotoxicity in rats.

    Science.gov (United States)

    Kalonia, Harikesh; Kumar, Puneet; Kumar, Anil

    2011-01-01

    A possible neuroprotective role has been recently suggested for 3H3MGCoA reductase inhibitors (statins). Here, we sought to determine neuroprotective effect of statins in quinolinic acid induced neurotoxicity in rats. Rats were surgically administered quinolinic acid and treated with Atorvastatin (10, 20 mg/kg), simvastatin (15, 30 mg/kg) and fluvastatin (5, 10 mg/kg) once daily up to 3 weeks. Atorvastatin (10, 20 mg/kg), simvastatin (30 mg/kg) and fluvastatin (10 mg/kg) treatment significantly attenuated the quinolinic acid induced behavioral (locomotor activity, rotarod performance and beam walk test), biochemical (lipid peroxidation, nitrite concentration, SOD and catalase), mitochondrial enzyme complex alterations in rats suggesting their free radical scavenging potential. Additionally, atorvastatin (10, 20 mg/kg), simvastatin (30 mg/kg) and fluvastatin (10 mg/kg) significantly decrease the TNF-α level and striatal lesion volume in quinolinic acid treated animals indicating their anti-inflammatory effects. In comparing the protective effect of different statins, atorvastatin is effective at both the doses while simvastatin and fluvastatins at respective lower doses were not able to produce the protective effect in quinolinic acid treated animals. These modulations can account, at least partly, for the beneficial effect of statins in our rodent model of striatal degeneration. Our findings show that statins could be explored as possible neuroprotective agents for neurodegenerative disorders such as HD.

  7. Curcumin-attenuated trinitrobenzene sulphonic acid induces chronic colitis by inhibiting expression of cyclooxygenase-2

    Institute of Scientific and Technical Information of China (English)

    Hua Jiang; Chang-Sheng Deng; Ming Zhang; Jian Xia

    2006-01-01

    AIM: To explore the possible mechanisms of curcumin in rat colitis induced by trinitrobenzene sulfonic (TNBS) acid. METHODS: Rats with TNBS acid-induced colitis were treated with curcumin (30 mg/kg or 60 mg/kg per day ip). Changes of body weight and histological scores as well as survival rate were evaluated. Leukocyte infiltration was detected by myeloperoxidase (MPO)activity assay. The expression of cyclooxygenase-2(COX-2) was detected by RT-PCR and Western blot.Inflammation cytokines were determined by RT-PCR.Local concentration of prostaglandin E2 (PGE2) in colon mucosa was determined by ELISA.RESULTS: Curcumin improved survival rate and histological image, decreased the macroscopic scores and MPO activity. Also curcumin reduced the expression of COX-2 and inflammation cytokines. In addition,treatment with curcumin increased the PGE2 level.CONCLUSION: Curcumin has therapeutic effects on TNBS acid-induced colitis, the mechanisms seem to be related to COX-2 inhibition and PGE2 improvement.

  8. Salicylic acid induces mitochondrial injury by inhibiting ferrochelatase heme biosynthesis activity.

    Science.gov (United States)

    Gupta, Vipul; Liu, Shujie; Ando, Hideki; Ishii, Ryohei; Tateno, Shumpei; Kaneko, Yuki; Yugami, Masato; Sakamoto, Satoshi; Yamaguchi, Yuki; Nureki, Osamu; Handa, Hiroshi

    2013-12-01

    Salicylic acid is a classic nonsteroidal anti-inflammatory drug. Although salicylic acid also induces mitochondrial injury, the mechanism of its antimitochondrial activity is not well understood. In this study, by using a one-step affinity purification scheme with salicylic acid-immobilized beads, ferrochelatase (FECH), a homodimeric enzyme involved in heme biosynthesis in mitochondria, was identified as a new molecular target of salicylic acid. Moreover, the cocrystal structure of the FECH-salicylic acid complex was determined. Structural and biochemical studies showed that salicylic acid binds to the dimer interface of FECH in two possible orientations and inhibits its enzymatic activity. Mutational analysis confirmed that Trp301 and Leu311, hydrophobic amino acid residues located at the dimer interface, are directly involved in salicylic acid binding. On a gel filtration column, salicylic acid caused a shift in the elution profile of FECH, indicating that its conformational change is induced by salicylic acid binding. In cultured human cells, salicylic acid treatment or FECH knockdown inhibited heme synthesis, whereas salicylic acid did not exert its inhibitory effect in FECH knockdown cells. Concordantly, salicylic acid treatment or FECH knockdown inhibited heme synthesis in zebrafish embryos. Strikingly, the salicylic acid-induced effect in zebrafish was partially rescued by FECH overexpression. Taken together, these findings illustrate that FECH is responsible for salicylic acid-induced inhibition of heme synthesis, which may contribute to its antimitochondrial and anti-inflammatory function. This study establishes a novel aspect of the complex pharmacological effects of salicylic acid.

  9. AXIAL SKELETAL AND HOX EXPRESSION DOMAIN ALTERATIONS INDUCED BY RETINOIC ACID, VALPROIC ACID AND BROMOXYNIL DURING MURINE DEVELOPMENT

    Science.gov (United States)

    ABSTRACT Retinoic acid (RA) alters the developmental fate of the axial skeletal anlage. "Anteriorizations" or "posteriorizations", the assumption of characteristics of embryonic areas normally anterior or posterior to the affected tissues, are correlated with altered emb...

  10. Retinoic acid prevents virus-induced airway hyperreactivity and M2 receptor dysfunction via anti-inflammatory and antiviral effects

    OpenAIRE

    Moreno-Vinasco, Liliana; Verbout, Norah G.; Fryer, Allison D.; Jacoby, David B.

    2009-01-01

    Inhibitory M2 muscarinic receptors on airway parasympathetic nerves normally limit acetylcholine release. Viral infections decrease M2 receptor function, increasing vagally mediated bronchoconstriction. Since retinoic acid deficiency causes M2 receptor dysfunction, we tested whether retinoic acid would prevent virus-induced airway hyperreactivity and prevent M2 receptor dysfunction. Guinea pigs infected with parainfluenza virus were hyperreactive to electrical stimulation of the vagus nerves,...

  11. Valproic Acid-Induced Severe Acute Pancreatitis with Pseudocyst Formation: Report of a Case.

    Science.gov (United States)

    Ray, Sukanta; Khamrui, Sujan; Kataria, Mohnish; Biswas, Jayanta; Saha, Suman

    2015-08-01

    Valproic acid is the most widely used anti-epilep-tic drug in children, and it is probably the most frequent cause of drug-induced acute pancreatitis. Outcomes for patients with valproic acid-associated pancreatitis vary from full recovery after discontinuation of the drug to severe acute pancreatitis and death. Here, we present a case of valproic acid-induced severe acute pancreatitis with pseudocyst formation in a 10-year-old girl with cerebral palsy and generalized tonic-clonic seizure. There was no resolution of the pseudocyst after discontinuation of valproic acid. The patient became symptomatic with a progressive increase in the size of the pseudocyst. She was successfully treated with cystogastrostomy and was well at 12-month follow-up.

  12. Cell wall dynamics modulate acetic acid-induced apoptotic cell death of Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    António Rego

    2014-08-01

    Full Text Available Acetic acid triggers apoptotic cell death in Saccharomyces cerevisiae, similar to mammalian apoptosis. To uncover novel regulators of this process, we analyzed whether impairing MAPK signaling affected acetic acid-induced apoptosis and found the mating-pheromone response and, especially, the cell wall integrity pathways were the major mediators, especially the latter, which we characterized further. Screening downstream effectors of this pathway, namely targets of the transcription factor Rlm1p, highlighted decreased cell wall remodeling as particularly important for acetic acid resistance. Modulation of cell surface dynamics therefore emerges as a powerful strategy to increase acetic acid resistance, with potential application in industrial fermentations using yeast, and in biomedicine to exploit the higher sensitivity of colorectal carcinoma cells to apoptosis induced by acetate produced by intestinal propionibacteria.

  13. Heat shock protein 70-dependent protective effect of polaprezinc on acetylsalicylic acid-induced apoptosis of rat intestinal epithelial cells.

    Science.gov (United States)

    Qin, Ying; Naito, Yuji; Handa, Osamu; Hayashi, Natsuko; Kuki, Aiko; Mizushima, Katsura; Omatsu, Tatsushi; Tanimura, Yuko; Morita, Mayuko; Adachi, Satoko; Fukui, Akifumi; Hirata, Ikuhiro; Kishimoto, Etsuko; Nishikawa, Taichiro; Uchiyama, Kazuhiko; Ishikawa, Takeshi; Takagi, Tomohisa; Yagi, Nobuaki; Kokura, Satoshi; Yoshikawa, Toshikazu

    2011-11-01

    Protection of the small intestine from mucosal injury induced by nonsteroidal anti-inflammatory drugs including acetylsalicylic acid is a critical issue in the field of gastroenterology. Polaprezinc an anti-ulcer drug, consisting of zinc and L-carnosine, provides gastric mucosal protection against various irritants. In this study, we investigated the protective effect of polaprezinc on acetylsalicylic acid-induced apoptosis of the RIE1 rat intestinal epithelial cell line. Confluent rat intestinal epithelial cells were incubated with 70 µM polaprezinc for 24 h, and then stimulated with or without 15 mM acetylsalicylic acid for a further 15 h. Subsequent cellular viability was quantified by fluorometric assay based on cell lysis and staining. Acetylsalicylic acid-induced cell death was also qualified by fluorescent microscopy of Hoechst33342 and propidium iodide. Heat shock proteins 70 protein expression after adding polaprezinc or acetylsalicylic acid was assessed by western blotting. To investigate the role of Heat shock protein 70, Heat shock protein 70-specific small interfering RNA was applied. Cell viability was quantified by fluorometric assay based on cell lysis and staining and apoptosis was analyzed by fluorescence-activated cell sorting. We found that acetylsalicylic acid significantly induced apoptosis of rat intestinal epithelial cells in a dose- and time-dependent manner. Polaprezinc significantly suppressed acetylsalicylic acid-induced apoptosis of rat intestinal epithelial cells at its late phase. At the same time, polaprezinc increased Heat shock protein 70 expressions of rat intestinal epithelial cells in a time-dependent manner. However, in Heat shock protein 70-silenced rat intestinal epithelial cells, polaprezinc could not suppress acetylsalicylic acid -induced apoptosis at its late phase. We conclude that polaprezinc-increased Heat shock protein 70 expression might be an important mechanism by which polaprezinc suppresses acetylsalicylic

  14. Unsaturated fatty acids induce mesenchymal stem cells to increase secretion of angiogenic mediators.

    Science.gov (United States)

    Smith, Andria N; Muffley, Lara A; Bell, Austin N; Numhom, Surawej; Hocking, Anne M

    2012-09-01

    Mesenchymal stem cells (MSC) represent emerging cell-based therapies for diabetes and associated complications. Ongoing clinical trials are using exogenous MSC to treat type 1 and 2 diabetes, cardiovascular disease and non-healing wounds due to diabetes. The majority of these trials are aimed at exploiting the ability of these multipotent mesenchymal stromal cells to release soluble mediators that reduce inflammation and promote both angiogenesis and cell survival at sites of tissue damage. Growing evidence suggests that MSC secretion of soluble factors is dependent on tissue microenvironment. Despite the contribution of fatty acids to the metabolic environment of type 2 diabetes, almost nothing is known about their effects on MSC secretion of growth factors and cytokines. In this study, human bone marrow-derived MSC were exposed to linoleic acid, an omega-6 polyunsaturated fatty acid, or oleic acid, a monounsaturated fatty acid, for seven days in the presence of 5.38 mM glucose. Outcomes measured included MSC proliferation, gene expression, protein secretion and chemotaxis. Linoleic and oleic acids inhibited MSC proliferation and altered MSC expression and secretion of known mediators of angiogenesis. Both unsaturated fatty acids induced MSC to increase secretion of interleukin-6, VEGF and nitric oxide. In addition, linoleic acid but not oleic acid induced MSC to increase production of interleukin-8. Collectively these data suggest that exposure to fatty acids may have functional consequences for MSC therapy. Fatty acids may affect MSC engraftment to injured tissue and MSC secretion of cytokines and growth factors that regulate local cellular responses to injury.

  15. Proteomic investigation into betulinic acid-induced apoptosis of human cervical cancer HeLa cells.

    Science.gov (United States)

    Xu, Tao; Pang, Qiuying; Zhou, Dong; Zhang, Aiqin; Luo, Shaman; Wang, Yang; Yan, Xiufeng

    2014-01-01

    Betulinic acid is a pentacyclic triterpenoid that exhibits anticancer functions in human cancer cells. This study provides evidence that betulinic acid is highly effective against the human cervical cancer cell line HeLa by inducing dose- and time-dependent apoptosis. The apoptotic process was further investigated using a proteomics approach to reveal protein expression changes in HeLa cells following betulinic acid treatment. Proteomic analysis revealed that there were six up- and thirty down-regulated proteins in betulinic acid-induced HeLa cells, and these proteins were then subjected to functional pathway analysis using multiple analysis software. UDP-glucose 6-dehydrogenase, 6-phosphogluconate dehydrogenase decarboxylating, chain A Horf6-a novel human peroxidase enzyme that involved in redox process, was found to be down-regulated during the apoptosis process of the oxidative stress response pathway. Consistent with our results at the protein level, an increase in intracellular reactive oxygen species was observed in betulinic acid-treated cells. The proteins glucose-regulated protein and cargo-selection protein TIP47, which are involved in the endoplasmic reticulum pathway, were up-regulated by betulinic acid treatment. Meanwhile, 14-3-3 family proteins, including 14-3-3β and 14-3-3ε, were down-regulated in response to betulinic acid treatment, which is consistent with the decrease in expression of the target genes 14-3-3β and 14-3-3ε. Furthermore, it was found that the antiapoptotic bcl-2 gene was down-regulated while the proapoptotic bax gene was up-regulated after betulinic acid treatment in HeLa cells. These results suggest that betulinic acid induces apoptosis of HeLa cells by triggering both the endoplasmic reticulum pathway and the ROS-mediated mitochondrial pathway.

  16. The Ayurvedic drug, Ksheerabala, ameliorates quinolinic acid-induced oxidative stress in rat brain.

    Science.gov (United States)

    Swathy, S S; Indira, M

    2010-01-01

    One of the mechanisms of neurotoxicity is the induction of oxidative stress. There is hardly any cure for neurotoxicity in modern medicine, whereas many drugs in Ayurveda possess neuroprotective effects; however, there is no scientific validation for these drugs. Ksheerabala is an ayurvedic drug which is used to treat central nervous system disorders, arthritis, and insomnia. The aim of our study was to evaluate the effect of Ksheerabala on quinolinic acid-induced toxicity in rat brain. The optimal dose of Ksheerabala was found from a dose escalation study, wherein it was found that Ksheerabala showed maximum protection against quinolinic acid-induced neurotoxicity at a dose of 15 microL/100 g body weight/day, which was selected for further experiments. Four groups of female albino rats were maintained for 21 days as follows: 1. Control group, 2. Quinolinic acid (55 microg/100 g body weight), 3. Ksheerabala (15 microL/100 g body weight), 4. Ksheerabala (15 microL/100 g body weight) + Quinolinic acid (55 microg/100 g body weight). At the end of the experimental period, levels of lipid peroxidation products, protein carbonyls, and activities of scavenging enzymes were analyzed. The results revealed that quinolinic acid intake caused enhanced lipid and protein peroxidation as evidenced by increased levels of peroxidation products such as malondialdehyde, hydroperoxide, conjugated dienes, and protein carbonyls. On the other hand, the activities of scavenging enzymes such as catalase, superoxide dismutase (SOD), glutathione peroxidase, and glutathione reductase as well as the concentration of glutathione were reduced. On coadminstration of Ksheerabala along with quinolinic acid, the levels of all the biochemical parameters were restored to near-normal levels, indicating the protective effect of the drug. These results were reinforced by histopathological studies.

  17. Retinoic acid is a key regulatory switch determining the difference between lung and thyroid fates in Xenopus laevis

    Directory of Open Access Journals (Sweden)

    Wang Jean H

    2011-12-01

    Full Text Available Abstract Background The lung and thyroid are derived from the anterior endoderm. Retinoic acid and Fgf signalling are known to be essential for development of the lung in mouse but little is known on how the lung and thyroid are specified in Xenopus. Results If either retinoic acid or Fgf signalling is inhibited, there is no differentiation of the lung as assayed by expression of sftpb. There is no change in expression of thyroid gland markers when retinoic acid signalling is blocked after gastrulation and when Fgf signalling is inhibited there is a short window of time where pax2 expression is inhibited but expression of other markers is unaffected. If exogenous retinoic acid is given to the embryo between embryonic stages 20 and 26, the presumptive thyroid expresses sftpb and sftpc, specific markers of lung differentiation and expression of key thyroid transcription factors is lost. When the presumptive thyroid is transplanted into the posterior embryo, it also expresses sftpb, although pax2 expression is not blocked. Conclusions After gastrulation, retinoic acid is required for lung but not thyroid differentiation in Xenopus while Fgf signalling is needed for lung but only for early expression of pax2 in the thyroid. Exposure to retinoic acid can cause the presumptive thyroid to switch to a lung developmental program.

  18. Transcriptomic analysis of Mandarin fish brain cells infected with infectious spleen and kidney necrosis virus with an emphasis on retinoic acid-inducible gene 1-like receptors and apoptosis pathways.

    Science.gov (United States)

    Hu, Xianqin; Fu, Xiaozhe; Li, Ningqiu; Dong, Xingxing; Zhao, Lijuan; Lan, Jiangfeng; Ji, Wei; Zhou, Weidong; Ai, Taoshan; Wu, Shuqin; Lin, Li

    2015-08-01

    Infectious spleen and kidney necrosis virus (ISKNV) has caused significant economic losses in the cultured Mandarin fish (Siniperca chuatsi) industry. The molecular mechanisms that underlie the pathogenesis of the viral infection remain poorly understood. In this study, deep RNA sequencing technique was used to analyze the transcriptomic profiles of Mandarin fish brain cells (CPB) at progressive time points after ISKNV infection. A total of 96,206,040 clean data from 98,235,240 sequence reads were obtained. These raw data were assembled into 66,787 unigenes. Among these unigenes, 33,225 and 29,210 had significant hit the Nr and SwissProt databases where they matched 27,537and 19,638 unique protein accessions, respectively. In the samples harvested at 24 or 72 h post of the infection, a total of 10,834 or 7584 genes were differentially expressed in infected CPB cells compared to non-infected cells, including 5445 or 3766 up-regulated genes and 5389 or 3818 down-regulated genes, respectively. In addition, 12 differentially expressed genes (DEGs) were validated by quantitative PCR. These DEGs were involved in many pathways of viral pathogenesis. Further analysis of the major DEGs genes involved in the RLRs and apoptosis pathways revealed some interesting findings. In the RLRs pathway, ISKNV infection inhibited the activation of NF-κB via over expression of the IKKB-α and IKKB-β and lessened expression of interleukin-1 receptor-associated kinase 4 (IRAK4). In the apoptosis pathway, ISKNV infection could induce apoptosis mainly via tumor necrosis factor (TNF) mediated extrinsic pathway. The cellular apoptosis induced by ISKNV infection was confirmed using annexinV-FITC/PI and DAPI staining methods.

  19. 饮食加硼治疗维甲酸诱导骨质疏松模型大鼠的效果观察%Therapeutic effect of dietary boron supplement on retinoic acid-induced osteoporosis in rats

    Institute of Scientific and Technical Information of China (English)

    许鹏; 胡万彪; 郭雄; 张银刚; 李幼芬; 姚建锋; 蔡乾坤

    2006-01-01

    目的 观察饮食加硼治疗维甲酸诱导的骨质疏松模型大鼠的效果,为硼临床治疗骨质疏松症提供实验依据.方法 SD大鼠32只,随机分为正常组(n=8)和骨质疏松模型组(n=24).以维甲酸80mg.kg-1.d-1灌胃15 d,诱导骨质疏松模型.模型复制成功后,骨质疏松模型组又随机分为无措施对照组(n=8)、饮食加硼治疗组(n=8)和雌二醇治疗组(n=8).治疗30 d后,测定大鼠血清钙、磷、硼含量,及碱性磷酸酶(AKP)和酸性磷酸酶(TRAP)活性,测量大鼠全身、腰椎和胫骨骨密度,并观察大鼠股骨形态计量学变化.结果 四组大鼠血清Ca和P含量无显著性差异,而硼含量硼治疗组明显高于其它三组.对照组大鼠血清AKP和TRAP活性增加,股骨松质骨和皮质骨骨量减少,破骨细胞数量增加,腰椎、胫骨骨密度下降,呈现骨质疏松变化.饮食加硼和雌激素治疗组大鼠血清TRAP活性显著下降,股骨平均骨小梁数、平均骨小梁宽度、骨小梁面积百分比、皮质骨面积百分比和全身、腰椎、胫骨骨密度等显著增加,松质骨区破骨细胞数明显减少,与正常组大鼠骨质无明显差异.硼治疗组大鼠血清AKP活性及松质骨区活跃成骨细胞数显著增加.结论 饮食加硼可提高大鼠血清硼含量,增加骨形成,减少骨吸收,对骨质疏松有明显的治疗作用.

  20. Comparative evaluation of retinoic acid, benzoyl peroxide and erythromycin lotion in acne vulgarils

    Directory of Open Access Journals (Sweden)

    Dogra A

    1993-01-01

    Full Text Available Ninety three patients suffering from acne vulgaris were treated with 0.05% retinoic acid (23 patients, 10% benzyoyl peroxide (24 patients, 2% erythromycin lotin (25 patients and 50% glycerine in methylated spirit (21 patients used as a control, for a period of 6 weeks. The patients were evaluated at 2 weeks and 6 weeks by spot counting of the lesions and diagrammatic representations. Good to excellent results were obtained in 69.6% of patients of erythromycin lotion. Retinoic acid was more effective in reducing noninflammatory lesions (75.2% whereas inflammatory lesions showed better response (73.6% with erythromycin lotion and benzoyl peroxide was almost equally effective in both types of lesions.

  1. Antagonism between Retinoic Acid and Fibroblast Growth Factor Signaling during Limb Development

    OpenAIRE

    Thomas J. Cunningham; Xianling Zhao; Lisa L. Sandell; Sylvia M. Evans; Paul A. Trainor; Gregg Duester

    2013-01-01

    The vitamin A metabolite retinoic acid (RA) provides patterning information during vertebrate embryogenesis, but the mechanism through which RA influences limb development is unclear. During patterning of the limb proximodistal axis (upper limb to digits), avian studies suggest that a proximal RA signal generated in the trunk antagonizes a distal fibroblast growth factor (FGF) signal. However, mouse and zebrafish genetic studies suggest that loss of RA suppresses forelimb initiation. Here, us...

  2. ISOLATION AND CHARACTERIZATION OF AXOLOTL NPDC-1 AND ITS EFFECTS ON RETINOIC ACID RECEPTOR SIGNALING

    OpenAIRE

    Theodosiou, Maria; Monaghan, James R; Spencer, Michael L; Voss, S. Randal; Noonan, Daniel J.

    2007-01-01

    Retinoic acid, a key morphogen in early vertebrate development and tissue regeneration, mediates its effects through the binding of receptors that act as ligand-induced transcription factors. These binding events function to recruit an array of transcription co-regulatory proteins to specific gene promoters. One such co-regulatory protein, neuronal proliferation and differentiation control-1 (NPDC-1), is broadly expressed during mammalian development and functions as an in vitro repressor of ...

  3. Human Gastric Epithelial Cells Contribute to Gastric Immune Regulation by Providing Retinoic Acid to Dendritic Cells

    OpenAIRE

    Bimczok, Diane; John Y. Kao; Zhang, Min; Cochrun, Steven; Mannon, Peter; Peter, Shajan; Wilcox, Charles M.; Mönkemüller, Klaus E; Harris, Paul R.; Grams, Jayleen M.; Stahl, Richard D.; Smith, Phillip D.; Smythies, Lesley E.

    2014-01-01

    Despite the high prevalence of chronic gastritis caused by H. pylori, the gastric mucosa has received little investigative attention as a unique immune environment. Here, we analyzed whether retinoic acid (RA), an important homeostatic factor in the small intestinal mucosa, also contributes to gastric immune regulation. We report that human gastric tissue contains high levels of the RA precursor molecule, retinol, and that gastric epithelial cells express both RA biosynthesis genes and RA res...

  4. Retinoic acid is enriched in Hensen's node and is developmentally regulated in the early chicken embryo.

    OpenAIRE

    Chen, Y; Huang, L; Russo, A F; Solursh, M

    1992-01-01

    Retinoic acid (RA) has been considered as a potential morphogen in the chicken limb and has also been suggested to be involved in early embryonic development. On the basis of biological activity, previous reports suggest that Hensen's node, the anatomical equivalent in the chicken of the Spemann's organizer, may contain RA. Here, by using a molecular assay system, we demonstrate that Hensen's node contains retinoids in a concentration approximately 20 times more than that in the neighboring t...

  5. A phosphorylation defective retinoic acid receptor mutant mimics the effects of retinoic acid on EGFR mediated AP-1 expression and cancer cell proliferation

    Directory of Open Access Journals (Sweden)

    Kim Randie

    2002-10-01

    Full Text Available Abstract Background The effects of the vitamin A metabolite retinoic acid (RA are mediated at the transcriptional level by retinoic acid receptors (RAR. These proteins are part of a superfamily of transcription factors which activate target gene expression when bound to their respective ligands. In addition to ligand binding, heterodimerization with transcriptional cofactors and posttranslational modification such as phosphorylation are also critical for transactivation function. Previous studies have shown that phosphorylation of a serine residue at amino acid 77 in the RARα amino terminus was required for basal activation function of the transcription factor. Results We have determined that RA inhibits cyclin H and cdk7 expression thereby decreasing levels of phosphorylated RARα in human cancer cell lines. To determine the effects of decreased RARα phosphorylation in human cancer cells, we stably transfected a phosphorylation defective mutant RARα expression construct into SCC25 cultures. Cells expressing the mutant RARα proliferated more slowly than control clones. This decreased proliferation was associated with increased cyclin dependent kinase inhibitor expression and decreased S phase entry. In the absence of ligand, the RARα mutant inhibited AP-1 activity to an extent similar to that of RA treated control clones. Levels of some AP-1 proteins were inhibited due to decreased EGFR expression upstream in the signaling pathway. Conclusions These results indicate that hypophosphorylated RARα can mimic the anti-AP-1 effects of RA in the absence of ligand.

  6. Phenylethanoids in the herb of Plantago lanceolata and inhibitory effect on arachidonic acid-induced mouse ear edema.

    Science.gov (United States)

    Murai, M; Tamayama, Y; Nishibe, S

    1995-10-01

    The five phenylethanoids, acteoside (1), cistanoside F (2), lavandulifolioside (3), plantamajoside (4) and isoacteoside (5) were isolated from the herb of Plantago lanceolata L. (Plantaginaceae). Compounds 1, the major phenylethanoid in the herb of P. lanceolata L., and 4, the major phenylethanoid in the herb of P. asiatica L., showed inhibitory effects on arachidonic acid-induced mouse ear edema.

  7. Gallic acid induces apoptosis in EGFR-mutant non-small cell lung cancers by accelerating EGFR turnover.

    Science.gov (United States)

    Nam, Boas; Rho, Jin Kyung; Shin, Dong-Myung; Son, Jaekyoung

    2016-10-01

    Gallic acid is a common botanic phenolic compound, which is present in plants and foods worldwide. Gallic acid is implicated in various biological processes such as cell growth and apoptosis. Indeed, gallic acid has been shown to induce apoptosis in many cancer types. However, the molecular mechanisms of gallic acid-induced apoptosis in cancer, particularly lung cancer, are still unclear. Here, we report that gallic acid induces apoptosis in EGFR-mutant non-small cell lung cancer (NSCLC) cells, but not in EGFR-WT NSCLC cells. Treatment with gallic acid resulted in a significant reduction in proliferation and induction of apoptosis, only in EGFR-mutant NSCLC cells. Interestingly, treatment with gallic acid led to a robust decrease in EGFR levels, which is critical for NSCLC survival. Treatment with gallic acid had no significant effect on transcription, but induced EGFR turnover. Indeed, treatment with a proteasome inhibitor dramatically reversed gallic acid-induced EGFR downregulation. Moreover, treatment with gallic acid induced EGFR turnover leading to apoptosis in EGFR-TKI (tyrosine kinase inhibitor)-resistant cell lines, which are dependent on EGFR signaling for survival. Thus, these studies suggest that gallic acid can induce apoptosis in EGFR-dependent lung cancers that are dependent on EGFR for growth and survival via acceleration of EGFR turnover.

  8. Rho Kinase ROCK2 Mediates Acid-Induced NADPH Oxidase NOX5-S Expression in Human Esophageal Adenocarcinoma Cells.

    Directory of Open Access Journals (Sweden)

    Jie Hong

    Full Text Available Mechanisms of the progression from Barrett's esophagus (BE to esophageal adenocarcinoma (EA are not fully understood. We have shown that NOX5-S may be involved in this progression. However, how acid upregulates NOX5-S is not well known. We found that acid-induced increase in NOX5-S expression was significantly decreased by the Rho kinase (ROCK inhibitor Y27632 in BE mucosal biopsies and FLO-1 EA cells. In addition, acid treatment significantly increased the Rho kinase activity in FLO-1 cells. The acid-induced increase in NOX5-S expression and H2O2 production was significantly decreased by knockdown of Rho kinase ROCK2, but not by knockdown of ROCK1. Conversely, the overexpression of the constitutively active ROCK2, but not the constitutively active ROCK1, significantly enhanced the NOX5-S expression and H2O2 production. Moreover, the acid-induced increase in Rho kinase activity and in NOX5-S mRNA expression was blocked by the removal of calcium in both FLO-1 and OE33 cells. The calcium ionophore A23187 significantly increased the Rho kinase activity and NOX5-S mRNA expression. We conclude that acid-induced increase in NOX5-S expression and H2O2 production may depend on the activation of ROCK2, but not ROCK1, in EA cells. The acid-induced activation of Rho kinase may be mediated by the intracellular calcium increase. It is possible that persistent acid reflux present in BE patients may increase the intracellular calcium, activate ROCK2 and thereby upregulate NOX5-S. High levels of reactive oxygen species derived from NOX5-S may cause DNA damage and thereby contribute to the progression from BE to EA.

  9. Rho Kinase ROCK2 Mediates Acid-Induced NADPH Oxidase NOX5-S Expression in Human Esophageal Adenocarcinoma Cells.

    Science.gov (United States)

    Hong, Jie; Li, Dan; Cao, Weibiao

    2016-01-01

    Mechanisms of the progression from Barrett's esophagus (BE) to esophageal adenocarcinoma (EA) are not fully understood. We have shown that NOX5-S may be involved in this progression. However, how acid upregulates NOX5-S is not well known. We found that acid-induced increase in NOX5-S expression was significantly decreased by the Rho kinase (ROCK) inhibitor Y27632 in BE mucosal biopsies and FLO-1 EA cells. In addition, acid treatment significantly increased the Rho kinase activity in FLO-1 cells. The acid-induced increase in NOX5-S expression and H2O2 production was significantly decreased by knockdown of Rho kinase ROCK2, but not by knockdown of ROCK1. Conversely, the overexpression of the constitutively active ROCK2, but not the constitutively active ROCK1, significantly enhanced the NOX5-S expression and H2O2 production. Moreover, the acid-induced increase in Rho kinase activity and in NOX5-S mRNA expression was blocked by the removal of calcium in both FLO-1 and OE33 cells. The calcium ionophore A23187 significantly increased the Rho kinase activity and NOX5-S mRNA expression. We conclude that acid-induced increase in NOX5-S expression and H2O2 production may depend on the activation of ROCK2, but not ROCK1, in EA cells. The acid-induced activation of Rho kinase may be mediated by the intracellular calcium increase. It is possible that persistent acid reflux present in BE patients may increase the intracellular calcium, activate ROCK2 and thereby upregulate NOX5-S. High levels of reactive oxygen species derived from NOX5-S may cause DNA damage and thereby contribute to the progression from BE to EA.

  10. Primary and secondary genetic responses after folic acid-induced acute renal injury in the mouse.

    Science.gov (United States)

    Calvet, J P; Chadwick, L J

    1994-12-01

    Folic acid-induced acute renal injury results in dramatic changes in gene expression. Among the genes affected by folic acid treatment are the primary response genes, c-fos and c-myc, which are thought to function to initiate cell cycle events. In this report, changes in the expression of three other genes in response to folic acid injury have been investigated: ornithine decarboxylase, epidermal growth factor (EGF), and sulfated glycoprotein-2 (SGP-2). Renal injury was found to cause a rapid decrease in EGF mRNA, which remained absent for several days after the initial injury, gradually returning to normal levels over an approximately 3-wk regeneration and recovery period. Ornithine decarboxylase mRNA showed a similar decrease. In contrast, folic acid caused a rapid increase in SGP-2 mRNA, which peaked several days after treatment, decreasing to normal levels over the 3-wk period. The mRNAs for the primary response genes were superinduced in the injured kidneys in the presence of the protein synthesis inhibitor cycloheximide. In contrast, the changes in EGF and SGP-2 mRNA levels were blocked by cycloheximide, indicating that these responses required new protein synthesis during the first few hours after folic acid injury. The opposite but parallel responses in the expression of the EGF and SGP-2 genes suggest that their regulation is coupled to the initial injury-induced dedifferentiation and subsequent return to the fully differentiated state.

  11. Folic acid induces salicylic acid-dependent immunity in Arabidopsis and enhances susceptibility to Alternaria brassicicola.

    Science.gov (United States)

    Wittek, Finni; Kanawati, Basem; Wenig, Marion; Hoffmann, Thomas; Franz-Oberdorf, Katrin; Schwab, Wilfried; Schmitt-Kopplin, Philippe; Vlot, A Corina

    2015-08-01

    Folates are essential for one-carbon transfer reactions in all organisms and contribute, for example, to de novo DNA synthesis. Here, we detected the folate precursors 7,8-dihydropteroate (DHP) and 4-amino-4-deoxychorismate (ADC) in extracts from Arabidopsis thaliana plants by Fourier transform ion cyclotron resonance-mass spectrometry. The accumulation of DHP, but not ADC, was induced after infection of plants with Pseudomonas syringae delivering the effector protein AvrRpm1. Application of folic acid or the DHP precursor 7,8-dihydroneopterin (DHN) enhanced resistance in Arabidopsis to P. syringae and elevated the transcript accumulation of the salicylic acid (SA) marker gene pathogenesis-related1 in both the treated and systemic untreated leaves. DHN- and folic acid-induced systemic resistance was dependent on SA biosynthesis and signalling. Similar to SA, folic acid application locally enhanced Arabidopsis susceptibility to the necrotrophic fungus Alternaria brassicicola. Together, the data associate the folic acid pathway with innate immunity in Arabidopsis, simultaneously activating local and systemic SA-dependent resistance to P. syringae and suppressing local resistance to A. brassicicola.

  12. Acupuncture suppresses kainic acid-induced neuronal death and inflammatory events in mouse hippocampus.

    Science.gov (United States)

    Kim, Seung-Tae; Doo, Ah-Reum; Kim, Seung-Nam; Kim, Song-Yi; Kim, Yoon Young; Kim, Jang-Hyun; Lee, Hyejung; Yin, Chang Shik; Park, Hi-Joon

    2012-09-01

    The administration of kainic acid (KA) causes seizures and produces neurodegeneration in hippocampal CA3 pyramidal cells. The present study investigated a possible role of acupuncture in reducing hippocampal cell death and inflammatory events, using a mouse model of kainic acid-induced epilepsy. Male C57BL/6 mice received acupuncture treatments at acupoint HT8 or in the tail area bilaterally once a day for 2 days and again immediately after an intraperitoneal injection of KA (30 mg/kg). HT8 is located on the palmar surface of the forelimbs, between the fourth and fifth metacarpal bones. Twenty-four hours after the KA injection, neuronal cell survival, the activations of microglia and astrocytes, and mRNA expression of two proinflammatory cytokines, interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α), were measured in the hippocampus. Acupuncture stimulation at HT8, but not in the tail area, significantly reduced the KA-induced seizure, neuron death, microglial and astrocyte activations, and IL-1β mRNA expression in the hippocampus. The acupuncture stimulation also decreased the mRNA expression of TNF-α, but it was not significant. These results indicate that acupuncture at HT8 can inhibit hippocampal cell death and suppress KA-induced inflammatory events, suggesting a possible role for acupuncture in the treatment of epilepsy.

  13. Acid-induced gelation behavior of casein/whey protein solutions assessed by oscillatory rheology.

    Science.gov (United States)

    Sadeghi, Mahboubeh; Madadlou, Ashkan; Khosrowshahi, Asghar; Mohammadifar, Mohammadamin

    2014-09-01

    Gelation process of acid-induced casein gels was studied using response surface method (RSM). Ratio of casein to whey proteins, incubation and heating temperatures were independent variables. Final storage modulus (G') measured 200 min after the addition of glucono-δ-lactone and the gelation time i.e. the time at which G' of gels became greater than 1 Pa were the parameters studied. Incubation temperature strongly affected both parameters. The higher the incubation temperature, the lower was the G' and the shorter the gelation time. Increased heating temperature however, increased the G' but again shortened the gelation time. Increase in G' was attributed to the formation of disulphide cross-linkages between denatured whey proteins and casein chains; whilst the latter was legitimized by considering the higher isoelectric pH of whey proteins. Maximum response (G' = 268.93 Pa) was obtained at 2.7 % w/w, 25 °C and 90 °C for casein content, incubation and heating temperatures, respectively.

  14. Effect of partial liquid ventilation on oleic acid-induced inflammatory responses in piglets

    Institute of Scientific and Technical Information of China (English)

    ZHU Yao-bin; WANG Qiang; LIU Ying-long; LI Xiao-feng; LI Jian-an; L(U) Xiao-dong; LING Feng; LIU Ai-jun; FAN Xiang-ming

    2010-01-01

    Background Pediatric patients are susceptible to lung injury.Acute lung injury (ALI) in children often results in a high mortality.Partial liquid ventilation (PLV) has been shown to markedly improve oxygenation and reduce histologic evidence of injury in a number of lung injury models.This study aimed to examine the hypothesis that PLV would attenuate the production of local and systemic cytokines in an immature piglet model of ALI induced by oleic acid (OA).Methods Twelve Chinese immature piglets were induced to develop ALI by oleic acid.The animals were randomly assigned to two groups (n=6): (1) conventional mechanical ventilation (MV) group and (2) PLV with FC-77 (10 ml/kg) group.Results Compared with MV group, PLV group got better cardiopulmonary variables (P <0.05).These variables included heart rate, mean blood pressure, blood pH, partial pressure of arterial oxygen (PaO2), PaO2/FiO2 and partial pressure of arterial carbon dioxide (PaCO2).Partial liquid ventilation reduced IL-1β, IL-6, IL-10 and TN F-α both in plasma and tissue concentrations compared with MV group (P <0.05).Conclusions Partial liquid ventilation provides protective effects against inflammatory responses in the lungs of oleic acid-induced immature piglets.

  15. Viscoelastic properties and fractal analysis of acid-induced SPI gels at different ionic strength.

    Science.gov (United States)

    Bi, Chong-hao; Li, Dong; Wang, Li-jun; Adhikari, Benu

    2013-01-30

    The viscoelastic property and scaling behavior of acid (glucono-δ-lactone)-induced soy protein isolate (SPI) gels were investigated at various ionic strengths (0-800mM) and five protein concentrations ranging between 4% and 8% (w/w). The infinite storage modulus ( [Formula: see text] ) and the gelation start time (t(g)) which indicate the progress of gelation process exhibited strong ionic strength dependence. The storage modulus and critical strain were found to exhibit a power-law relationship with protein concentration. Rheological analysis and confocal laser scanning microscopy (CLSM) analysis were applied to estimate the fractal dimensions (D(f)) of the gels and the values were found to vary between 2.319 and 2.729. The comparison of the rheological methods and the CLSM image analysis method showed that the Shih, Shih, Kim, Liu, and Aksay (1990) model was better suited in estimating the D(f) value of acid-induced SPI gel system.

  16. PGC-1alpha inhibits oleic acid induced proliferation and migration of rat vascular smooth muscle cells.

    Directory of Open Access Journals (Sweden)

    Yan Zhang

    Full Text Available BACKGROUND: Oleic acid (OA stimulates vascular smooth muscle cell (VSMC proliferation and migration. The precise mechanism is still unclear. We sought to investigate the effects of peroxisome proliferator-activated receptor gamma (PPARgamma coactivator-1 alpha (PGC-1alpha on OA-induced VSMC proliferation and migration. PRINCIPAL FINDINGS: Oleate and palmitate, the most abundant monounsaturated fatty acid and saturated fatty acid in plasma, respectively, differently affect the mRNA and protein levels of PGC-1alpha in VSMCs. OA treatment resulted in a reduction of PGC-1alpha expression, which may be responsible for the increase in VSMC proliferation and migration caused by this fatty acid. In fact, overexpression of PGC-1alpha prevented OA-induced VSMC proliferation and migration while suppression of PGC-1alpha by siRNA enhanced the effects of OA. In contrast, palmitic acid (PA treatment led to opposite effects. This saturated fatty acid induced PGC-1alpha expression and prevented OA-induced VSMC proliferation and migration. Mechanistic study demonstrated that the effects of PGC-1alpha on VSMC proliferation and migration result from its capacity to prevent ERK phosphorylation. CONCLUSIONS: OA and PA regulate PGC-1alpha expression in VSMCs differentially. OA stimulates VSMC proliferation and migration via suppression of PGC-1alpha expression while PA reverses the effects of OA by inducing PGC-1alpha expression. Upregulation of PGC-1alpha in VSMCs provides a potential novel strategy in preventing atherosclerosis.

  17. Anacardic acid induces apoptosis-like cell death in the rice blast fungus Magnaporthe oryzae.

    Science.gov (United States)

    Muzaffar, Suhail; Bose, Chinchu; Banerji, Ashok; Nair, Bipin G; Chattoo, Bharat B

    2016-01-01

    Anacardic acid (6-pentadecylsalicylic acid), extracted from cashew nut shell liquid, is a natural phenolic lipid well known for its strong antibacterial, antioxidant, and anticancer activities. Its effect has been well studied in bacterial and mammalian systems but remains largely unexplored in fungi. The present study identifies antifungal, cytotoxic, and antioxidant activities of anacardic acid in the rice blast fungus Magnaporthe oryzae. It was found that anacardic acid causes inhibition of conidial germination and mycelial growth in this ascomycetous fungus. Phosphatidylserine externalization, chromatin condensation, DNA degradation, and loss of mitochondrial membrane potential suggest that growth inhibition of fungus is mainly caused by apoptosis-like cell death. Broad-spectrum caspase inhibitor Z-VAD-FMK treatment indicated that anacardic acid induces caspase-independent apoptosis in M. oryzae. Expression of a predicted ortholog of apoptosis-inducing factor (AIF) was upregulated during the process of apoptosis, suggesting the possibility of mitochondria dependent apoptosis via activation of apoptosis-inducing factor. Anacardic acid treatment leads to decrease in reactive oxygen species rather than increase in reactive oxygen species (ROS) accumulation normally observed during apoptosis, confirming the antioxidant properties of anacardic acid as suggested by earlier reports. Our study also shows that anacardic acid renders the fungus highly sensitive to DNA damaging agents like ethyl methanesulfonate (EMS). Treatment of rice leaves with anacardic acid prevents M. oryzae from infecting the plant without affecting the leaf, suggesting that anacardic acid can be an effective antifungal agent.

  18. Involvement of Sp1 in Butyric Acid-Induced HIV-1 Gene Expression

    Directory of Open Access Journals (Sweden)

    Kenichi Imai

    2015-09-01

    Full Text Available Background/Aims: The ability of human immunodeficiency virus-1(HIV-1 to establish latent infection and its re-activation is considered critical for progression of HIV-1 infection. We previously reported that a bacterial metabolite butyric acid, acting as a potent inhibitor of histone deacetylases (HDACs, could lead to induction of HIV-1 transcription; however, the molecular mechanism remains unclear. The aim of this study was to investigate the effect of butyric acid on HIV-1 gene expression. Methods: Butyric acid-mediated HIV-1 gene expression was determined by luciferase assay and Chromatin immunoprecipitation assay. Western blot analysis and ELISA were used for the detection of HIV-1. Results: We found that Sp1 binding sites within the HIV-1 promoter are primarily involved in butyric acid-mediated HIV-1 activation. In fact, Sp1 knockdown by small interfering RNA and the Sp1 inhibitor mithramycin A abolished the effect of butyric acid. We also observed that cAMP response element-binding-binding protein (CBP was required for butyric acid-induced HIV-1 activation. Conclusions: These results suggest that butyric acid stimulates HIV-1 promoter through inhibition of the Sp1-associated HDAC activity and recruitment of CBP to the HIV-1 LTR. Our findings suggest that Sp1 should be considered as one of therapeutic targets in anti-viral therapy against HIV-1 infection aggravated by butyric acid-producing bacteria.

  19. Neuroprotective effects of MK-801 on L-2-chloropropionic acid-induced neurotoxicity.

    Science.gov (United States)

    Williams, R E; Lock, E A; Bachelard, H S

    2001-02-01

    L-2-Chloropropionic acid is selectively toxic to the cerebellum in rats; the granule cell necrosis observed within 48 h can be prevented by prior administration of MK-801. Short-term treatment (2 h) with L-2-chloropropionic acid has also been shown to activate the mitochondrial pyruvate dehydrogenase complex in fasted adult rats. This study aimed to investigate the effect of prior exposure to MK-801 on the biochemical and neurotoxicological effects of L-2-chloropropionic acid. Extracts were prepared from the forebrain and cerebellum of animals that had been treated with L-2-chloropropionic acid, with and without prior treatment with MK-801, and were analysed using magnetic resonance spectroscopy and amino acid analysis. Glucose metabolism was studied by monitoring the metabolism of [1-(13)C]-glucose using GC/MS. L-2-Chloropropionic acid caused increased glucose metabolism in both brain regions 6 h after administration, confirming activation of the pyruvate dehydrogenase complex, which was not prevented by MK-801. After 48 h an increase in lactate and a decrease in N-acetylaspartate was observed only in the cerebellum, whereas phosphocreatine and ATP decreased in both tissues. MK-801 prevented the changes in lactate and N:-acetylaspartate, but not those on the energy state. These studies suggest that L-2-chloropropionic acid-induced neurotoxicity is only partly mediated by the NMDA subtype of glutamate receptor.

  20. Linoleic acid-induced mitochondrial Ca(2+ efflux causes peroxynitrite generation and protein nitrotyrosylation.

    Directory of Open Access Journals (Sweden)

    Hong-Mei Zhang

    Full Text Available It is well known that excessive non-esterified fatty acids in diabetes contribute to the pathogenesis of renal complications although the mechanism remains elusive. Enhanced oxidative stress has been hypothesized as a unified factor contributing to diabetic complications and increased protein nitrotyrosylation has been reported in the kidneys of diabetic patients. In the current manuscript we described that linoleic acid (LA caused mitochondrial Ca(2+ efflux and peroxynitrite production, along with increased nitrotyrosine levels of cellular proteins in primary human mesangial cells. The peroxynitrite production by LA was found to depend on mitochondrial Ca(2+ efflux. Downregulation of hsp90beta1, which has been previously shown to be essential for polyunsaturated fatty acid-induced mitochondrial Ca(2+ efflux, significantly diminished LA-responsive mitochondrial Ca(2+ efflux and the coupled peroxynitrite generation, implicating a critical role of hsp90beta1 in the LA responses. Our results further demonstrated that mitochondrial complexes I and III were directly involved in the LA-induced peroxynitrite generation. Using the well established type 2 diabetic animal model db/db mice, we observed a dramatically enhanced LA responsive mitochondrial Ca(2+ efflux and protein nitrotyrosylation in the kidney. Our study thus demonstrates a cause-effect relationship between LA and peroxynitrite or protein nitrotyrosylation and provides a novel mechanism for lipid-induced nephropathy in diabetes.

  1. Molecular cloning and analysis of functional cDNA and genomic clones encoding bovine cellular retinoic acid-binding protein.

    Science.gov (United States)

    Shubeita, H E; Sambrook, J F; McCormick, A M

    1987-08-01

    A recombinant cDNA clone, pCRABP-HS1, encoding cellular retinoic acid-binding protein was isolated from a bovine adrenal cDNA library. COS-7 cells transfected with pCRABP-HS1 produced a biologically active retinoic acid-binding protein molecule of the expected molecular mass (15.5 kDa). RNA blot hybridization analysis using pCRABP-HS1 as a probe revealed a single 1050-nucleotide mRNA species in bovine adrenal, uterus, and testis, tissues that contain the highest levels of retinoic acid-binding activity. No hybridization was detected in RNA extracted from ovary, spleen, kidney, or liver, which contain relatively low levels of cellular retinoic acid-binding protein activity. Analysis of genomic clones isolated from an EcoRI bovine genomic library demonstrated that the bovine cellular retinoic acid-binding protein gene is composed of four exons and three introns. Two putative promoter sequences were identified in the cloned 5' sequence of the gene.

  2. Caesium fluoride-promoted Stille coupling reaction: an efficient synthesis of 9Z-retinoic acid and its analogues using a practical building block.

    Science.gov (United States)

    Okitsu, Takashi; Iwatsuka, Kinya; Wada, Akimori

    2008-12-21

    A highly efficient and rapid total synthesis of 9Z-retinoic acid was accomplished by caesium fluoride-promoted Stille coupling reaction; using a common building block, 9Z-retinoic acid analogues were also prepared by the same method without isomerisation of the Z-double bond.

  3. Effect of terbutaline on alveolar liquid clearance after oleic acid-induced lung injury in rats

    Institute of Scientific and Technical Information of China (English)

    TAO Jun; YANG Tian-de; LI Hong; DU Zhi-yong

    2006-01-01

    Objective: To investigate whether terbutaline affects alveolar liquid clearance after oleic acid-induced lung injury in rats.Methods: Forty healthy Wistar rats ( weighing 250-280 g) were randomly divided into five groups ( n = 8 in each group): the normal control group ( control group),oleic acid injury group ( injury group), terbutaline-treated group (terbutaline group ), terbutaline plus amiloridetreated group (terbutaline + amiloride group ) and terbutaline plus ouabain-treated group (terbutaline + ouabain group). Acute lung injury model was induced by intravenous oleic acid (0. 25 mi/kg body weight). 24 hours later, 1.5 μCi 125I-labeled 5% albumin solution (5 ml/kg body weight) was dripped into the lungs through trachea.The alveolar liquid clearance rate, extravascular lung water content, and arterial blood gas were measured 1 hour thereafter.Results: At 24 hours after infusion of oleic acid, the rats developed pulmonary edema and severe hypoxemia,with the alveolar liquid clearance rate decreased by 49.2 % and the extravascular lung water content elevated by 47.9%. Compared with the rats in the injury group,terbutaline (10-4 mol/L ) significantly increased the alveolar liquid clearance rate, decreased the extravascular lung water content and improved hypoxemia. The effect of terbutaline was partly blocked by amiloride and ouabain,which were inhibitors of sodium transport. Terbutaline increased the alveolar liquid clearance rate by 63.7 %, and amiloride and ouabain reduced the alveolar liquid clearance rate by 54.7% and 56.8%, respectively.Conclusions: Terbutaline can accelerate alveolar liquid clearance through increasing sodium transport to attenuate pulmonary edema, thus improving gas exchange,which may have therapeutical effect on pulmonary edema after acute lung injury.

  4. Oral Grapeseed Oil and Sesame Oil in Experimental Acetic Acid-Induced Ulcerative Colitis in Rat

    Directory of Open Access Journals (Sweden)

    Hosseinzadeh

    2016-06-01

    Full Text Available Background Ulcerative colitis (UC is a multi-factorial disease with unknown etiology and has many clinical manifestations. Objectives The current study aimed to evaluate the effects of sesame oil (SO and grapeseed oil (GSO on acetic acid-induced UC in rats. Materials and Methods Eighty male rats were divided into eight groups as health control (HC1, received normal saline; HC2, received SO; HC3, received GSO; negative control (NC, UC and normal saline; positive control (PC, UC and mesalamine; SO, UC and SO; GSO, UC and GSO, and SO + GSO. The daily weight changes, serum levels of oxidative stress markers and lipid profile plus colon macroscopic and microscopic histological changes were measured at the end of the seventh day. Results Significant differences were detected between HC1 and PC on the 3rd (P = 0.002, 4th (0.013 and 6th days (0.014 and between HC1 and NC on the 4th day (0.027 in weight of rats. Use of GSO alone or in combination with SO decreased the extent of the changes both in macroscopic and microscopic indices and also at the inflammation level. The most significant decrease in the MDA level and the most obvious increase in the TAC belonged to the GSO group in comparison to the NC group. The lowest cholesterol (51.43 ± 5.62 mg/dL and HDL levels (29.29 ± 6.24 mg/dL were detected in response to SO consumption in comparison to NC group (P = 0.030 and P = 0.257, respectively. Conclusions GSO in combination with SO may be considered as the treatment of choice for UC based on antioxidant and histopathological evaluations.

  5. Bile acid-induced arrhythmia is mediated by muscarinic M2 receptors in neonatal rat cardiomyocytes.

    Directory of Open Access Journals (Sweden)

    Siti H Sheikh Abdul Kadir

    Full Text Available BACKGROUND: Intrahepatic cholestasis of pregnancy (ICP is a common disease affecting up to 5% of pregnancies and which can cause fetal arrhythmia and sudden intrauterine death. We previously demonstrated that bile acid taurocholate (TC, which is raised in the bloodstream of ICP, can acutely alter the rate and rhythm of contraction and induce abnormal calcium destabilization in cultured neonatal rat cardiomyocytes (NRCM. Apart from their hepatic functions bile acids are ubiquitous signalling molecules with diverse systemic effects mediated by either the nuclear receptor FXR or by a recently discovered G-protein coupled receptor TGR5. We aim to investigate the mechanism of bile-acid induced arrhythmogenic effects in an in-vitro model of the fetal heart. METHODS AND RESULTS: Levels of bile acid transporters and nuclear receptor FXR were studied by quantitative real time PCR, western blot and immunostaining, which showed low levels of expression. We did not observe functional involvement of the canonical receptors FXR and TGR5. Instead, we found that TC binds to the muscarinic M(2 receptor in NRCM and serves as a partial agonist of this receptor in terms of inhibitory effect on intracellular cAMP and negative chronotropic response. Pharmacological inhibition and siRNA-knockdown of the M(2 receptor completely abolished the negative effect of TC on contraction, calcium transient amplitude and synchronisation in NRCM clusters. CONCLUSION: We conclude that in NRCM the TC-induced arrhythmia is mediated by the partial agonism at the M(2 receptor. This mechanism might serve as a promising new therapeutic target for fetal arrhythmia.

  6. Mechanism of Ascorbic Acid-induced Reversion Against Malignant Phenotype in Human Gastric Cancer Cells

    Institute of Scientific and Technical Information of China (English)

    YA-XUAN SUN; QIU-SHENG ZHENG; GANG LI; DE-AN GUO; ZI-REN WANG

    2006-01-01

    Objective To find out the mechanisms of redifferentiation and reversion of malignant human gastric cancer cells induced by ascorbic acid. Methods Human gastric cancer cells grown in the laboratory were used. The Trypan blue dye exclusion method was used to determine the cell doubling time. The electrophoresis rate and colonogenic potential were the indices used to measure the rate of redifferentiation. The content of malondialdehyde (MDA) was measured using the thiobarbituric acid(TBA) method. The activities of superoxide dismutase (SOD), catalase (CAT) and the content of H2O2 were evaluated by spectrophotography. Results Six mmol/L ascorbic acid was used as a positive control. Human gastric cancer cells were treated with 75 μm hydrogen peroxide, which alleviated many of the malignant characteristics. For example, the cell surface charge obviously decreased and the electrophoresis rate dropped from 2.21 to 1.10 μm·s-1·V-1·cm-1. The colonogenic potential, a measure of cell differentiation, decreased 90.2%. After treatment with ascorbic acid, there was a concentration- and time-dependent increase in hydrogen peroxide (H2O2) and the activity of superoxide dismutase (SOD). However, the activity of catalase (CAT) resulted in a concentration- and time-dependent decrease. SOD and 3-amino-1,2,4-triazole (AT) exhibited some effects, but there were statistically significant differences between the SOD and AT group and the H2O2 group. Conclusions Ascorbic acid induces growth inhibition and redifferentiation of human gastric cancer cells through the production of hydrogen peroxide.

  7. Bile acid-induced necrosis in primary human hepatocytes and in patients with obstructive cholestasis

    Energy Technology Data Exchange (ETDEWEB)

    Woolbright, Benjamin L.; Dorko, Kenneth [Department of Pharmacology, Toxicology & Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States); Antoine, Daniel J.; Clarke, Joanna I. [MRC Centre for Drug Safety Science, Department of Molecular and Clinical Pharmacology, Institute of Translational Medicine, University of Liverpool, Liverpool (United Kingdom); Gholami, Parviz [Department of Internal Medicine, University of Kansas Medical Center, Kansas City, KS (United States); Li, Feng [Department of Pharmacology, Toxicology & Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States); Kumer, Sean C.; Schmitt, Timothy M.; Forster, Jameson [Department of Surgery, University of Kansas Medical Center, Kansas City, KS (United States); Fan, Fang [Department of Pathology, University of Kansas Medical Center, Kansas City, KS (United States); Jenkins, Rosalind E.; Park, B. Kevin [MRC Centre for Drug Safety Science, Department of Molecular and Clinical Pharmacology, Institute of Translational Medicine, University of Liverpool, Liverpool (United Kingdom); Hagenbuch, Bruno [Department of Pharmacology, Toxicology & Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States); Olyaee, Mojtaba [Department of Internal Medicine, University of Kansas Medical Center, Kansas City, KS (United States); Jaeschke, Hartmut, E-mail: hjaeschke@kumc.edu [Department of Pharmacology, Toxicology & Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States)

    2015-03-15

    Accumulation of bile acids is a major mediator of cholestatic liver injury. Recent studies indicate bile acid composition between humans and rodents is dramatically different, as humans have a higher percent of glycine conjugated bile acids and increased chenodeoxycholate content, which increases the hydrophobicity index of bile acids. This increase may lead to direct toxicity that kills hepatocytes, and promotes inflammation. To address this issue, this study assessed how pathophysiological concentrations of bile acids measured in cholestatic patients affected primary human hepatocytes. Individual bile acid levels were determined in serum and bile by UPLC/QTOFMS in patients with extrahepatic cholestasis with, or without, concurrent increases in serum transaminases. Bile acid levels increased in serum of patients with liver injury, while biliary levels decreased, implicating infarction of the biliary tracts. To assess bile acid-induced toxicity in man, primary human hepatocytes were treated with relevant concentrations, derived from patient data, of the model bile acid glycochenodeoxycholic acid (GCDC). Treatment with GCDC resulted in necrosis with no increase in apoptotic parameters. This was recapitulated by treatment with biliary bile acid concentrations, but not serum concentrations. Marked elevations in serum full-length cytokeratin-18, high mobility group box 1 protein (HMGB1), and acetylated HMGB1 confirmed inflammatory necrosis in injured patients; only modest elevations in caspase-cleaved cytokeratin-18 were observed. These data suggest human hepatocytes are more resistant to human-relevant bile acids than rodent hepatocytes, and die through necrosis when exposed to bile acids. These mechanisms of cholestasis in humans are fundamentally different to mechanisms observed in rodent models. - Highlights: • Cholestatic liver injury is due to cytoplasmic bile acid accumulation in hepatocytes. • Primary human hepatocytes are resistant to BA-induced injury

  8. Pistacia lentiscus resin regulates intestinal damage and inflammation in trinitrobenzene sulfonic acid-induced colitis.

    Science.gov (United States)

    Gioxari, Aristea; Kaliora, Andriana C; Papalois, Apostolos; Agrogiannis, George; Triantafillidis, John K; Andrikopoulos, Nikolaos K

    2011-11-01

    Mastic (Pistacia lentiscus) of the Anacardiaceae family has exhibited anti-inflammatory and antioxidant properties in patients with Crohn's disease. This study was based on the hypothesis that mastic inhibits intestinal damage in inflammatory bowel disease, regulating inflammation and oxidative stress in intestinal epithelium. Four different dosages of P. lentiscus powder in the form of powder were administered orally to trinitrobenzene sulfonic acid-induced colitic rats. Eighty-four male Wistar rats were randomly assigned to seven groups: A, control; B, colitic; C-F, colitic rats daily supplemented with P. lentiscus powder at (C) 50 mg/kg, (D) 100 mg/kg, (E) 200 mg/kg, and (F) 300 mg/kg of body weight; and G, colitic rats treated daily with cortisone (25 μg/kg of body weight). Colonic damage was assessed microscopically. The cytokines tumor necrosis factor-α, intercellular adhesion molecule-1 (ICAM-1), interleukin (IL)-6, IL-8, and IL-10 and malonaldehyde were measured in colonic specimens. Results were expressed as mean ± SE values. Histological amelioration of colitis (P≤.001) and significant differences in colonic indices occurred after 3 days of treatment. Daily administration of 100 mg of P. lentiscus powder/kg of body weight decreased all inflammatory cytokines (P≤.05), whereas 50 mg of P. lentiscus powder/kg of body weight and cortisone treatment reduced only ICAM-1 (P≤.05 and P≤.01, respectively). Malonaldehyde was significantly suppressed in all treated groups (P≤.01). IL-10 remained unchanged. Cytokines and malonaldehyde remained unaltered after 6 days of treatment. Thus P. lentiscus powder could possibly have a therapeutic role in Crohn's disease, regulating oxidant/antioxidant balance and modulating inflammation.

  9. Allosteric Regulation in the Ligand Binding Domain of Retinoic Acid Receptorγ

    Science.gov (United States)

    Amal, Ismail; Lutzing, Régis; Stote, Roland H.; Rochette-Egly, Cécile; Rochel, Natacha; Dejaegere, Annick

    2017-01-01

    Retinoic acid (RA) plays key roles in cell differentiation and growth arrest through nuclear retinoic acid receptors (RARs), which are ligand-dependent transcription factors. While the main trigger of RAR activation is the binding of RA, phosphorylation of the receptors has also emerged as an important regulatory signal. Phosphorylation of the RARγ N-terminal domain (NTD) is known to play a functional role in neuronal differentiation. In this work, we investigated the phosphorylation of RARγ ligand binding domain (LBD), and present evidence that the phosphorylation status of the LBD affects the phosphorylation of the NTD region. We solved the X-ray structure of a phospho-mimetic mutant of the LBD (RARγ S371E), which we used in molecular dynamics simulations to characterize the consequences of the S371E mutation on the RARγ structural dynamics. Combined with simulations of the wild-type LBD, we show that the conformational equilibria of LBD salt bridges (notably R387-D340) are affected by the S371E mutation, which likely affects the recruitment of the kinase complex that phosphorylates the NTD. The molecular dynamics simulations also showed that a conservative mutation in this salt bridge (R387K) affects the dynamics of the LBD without inducing large conformational changes. Finally, cellular assays showed that the phosphorylation of the NTD of RARγ is differentially regulated by retinoic acid in RARγWT and in the S371N, S371E and R387K mutants. This multidisciplinary work highlights an allosteric coupling between phosphorylations of the LBD and the NTD of RARγ and supports the importance of structural dynamics involving electrostatic interactions in the regulation of RARs activity. PMID:28125680

  10. Recessive and dominant mutations in retinoic acid receptor beta in cases with microphthalmia and diaphragmatic hernia.

    Science.gov (United States)

    Srour, Myriam; Chitayat, David; Caron, Véronique; Chassaing, Nicolas; Bitoun, Pierre; Patry, Lysanne; Cordier, Marie-Pierre; Capo-Chichi, José-Mario; Francannet, Christine; Calvas, Patrick; Ragge, Nicola; Dobrzeniecka, Sylvia; Hamdan, Fadi F; Rouleau, Guy A; Tremblay, André; Michaud, Jacques L

    2013-10-01

    Anophthalmia and/or microphthalmia, pulmonary hypoplasia, diaphragmatic hernia, and cardiac defects are the main features of PDAC syndrome. Recessive mutations in STRA6, encoding a membrane receptor for the retinol-binding protein, have been identified in some cases with PDAC syndrome, although many cases have remained unexplained. Using whole-exome sequencing, we found that two PDAC-syndrome-affected siblings, but not their unaffected sibling, were compound heterozygous for nonsense (c.355C>T [p.Arg119(∗)]) and frameshift (c.1201_1202insCT [p.Ile403Serfs(∗)15]) mutations in retinoic acid receptor beta (RARB). Transfection studies showed that p.Arg119(∗) and p.Ile403Serfs(∗)15 altered RARB had no transcriptional activity in response to ligands, confirming that the mutations induced a loss of function. We then sequenced RARB in 15 subjects with anophthalmia and/or microphthalmia and at least one other feature of PDAC syndrome. Surprisingly, three unrelated subjects with microphthalmia and diaphragmatic hernia showed de novo missense mutations affecting the same codon; two of the subjects had the c.1159C>T (Arg387Cys) mutation, whereas the other one carried the c.1159C>A (p.Arg387Ser) mutation. We found that compared to the wild-type receptor, p.Arg387Ser and p.Arg387Cys altered RARB induced a 2- to 3-fold increase in transcriptional activity in response to retinoic acid ligands, suggesting a gain-of-function mechanism. Our study thus suggests that both recessive and dominant mutations in RARB cause anophthalmia and/or microphthalmia and diaphragmatic hernia, providing further evidence of the crucial role of the retinoic acid pathway during eye development and organogenesis.

  11. Priming by Hexanoic Acid Induce Activation of Mevalonic and Linolenic Pathways and Promotes the Emission of Plant Volatiles

    OpenAIRE

    Eugenio eLlorens; Gemma eCamañes; Leonor eLapeña; Pilar eGarcía-Agustín

    2016-01-01

    Hexanoic acid is a short natural monocarboxylic acid present in some fruits and plants. Previous studies reported that soil drench application of this acid induces effective resistance in tomato plants against Botrytis cinerea and Pseudomonas syringae and in citrus against Alternaria alternata and Xanthomonas citri. In this work, we performed an in deep study of the metabolic changes produced in citrus by the application of hexanoic acid in response to the challenge pathogen Alternaria altern...

  12. The influence of pretreatment with ghrelin on the development of acetic-acid-induced colitis in rats.

    Science.gov (United States)

    Maduzia, D; Matuszyk, A; Ceranowicz, D; Warzecha, Z; Ceranowicz, P; Fyderek, K; Galazka, K; Dembinski, A

    2015-12-01

    Ghrelin has been primarily shown to exhibit protective and therapeutic effect in the gut. Pretreatment with ghrelin inhibits the development of acute pancreatitis and accelerates pancreatic recovery in the course of this disease. In the stomach, ghrelin reduces gastric mucosal damage induced by ethanol, stress or alendronate, as well as accelerates the healing of acetic acid-induced gastric and duodenal ulcer. The aim of present studies was to investigate the effect of pretreatment with ghrelin on the development of acetic acid-induced colitis. Studies have been performed on male Wistar rats. Animals were treated intraperitoneally with saline (control) or ghrelin (4, 8 or 16 nmol/kg/dose). Saline or ghrelin was given twice: 8 and 1 h before induction of colitis. Colitis was induced by a rectal enema with 1 ml of 4% solution of acetic acid and the severity of colitis was assessed 1 or 24 hours after induction of inflammation. Rectal administration of acetic acid induced colitis in all animals. Damage of colonic wall was seen at the macroscopic and microscopic level. This effect was accompanied by a reduction in colonic blood flow and mucosal DNA synthesis. Moreover, induction of colitis significantly increased mucosal concentration of pro-inflammatory interleukin-1β (IL-1β), activity of myeloperoxidase and concentration of malondialdehyde (MDA). Mucosal activity of superoxide dismutase (SOD) was reduced. Pretreatment with ghrelin reduced the area and grade of mucosal damage. This effect was accompanied by an improvement of blood flow, DNA synthesis and SOD activity in colonic mucosa. Moreover, ghrelin administration reduced mucosal concentration of IL-1β and MDA, as well as decreased mucosal activity of myeloperoxidase. Administration of ghrelin protects the large bowel against the development of the acetic acid-induced colitis and this effect seems to be related to the ghrelin-evoked anti-inflammatory and anti-oxidative effects.

  13. Ameliorative effects of polyunsaturated fatty acids against palmitic acid-induced insulin resistance in L6 skeletal muscle cells

    Directory of Open Access Journals (Sweden)

    Sawada Keisuke

    2012-03-01

    Full Text Available Abstract Background Fatty acid-induced insulin resistance and impaired glucose uptake activity in muscle cells are fundamental events in the development of type 2 diabetes and hyperglycemia. There is an increasing demand for compounds including drugs and functional foods that can prevent myocellular insulin resistance. Methods In this study, we established a high-throughput assay to screen for compounds that can improve myocellular insulin resistance, which was based on a previously reported non-radioisotope 2-deoxyglucose (2DG uptake assay. Insulin-resistant muscle cells were prepared by treating rat L6 skeletal muscle cells with 750 μM palmitic acid for 14 h. Using the established assay, the impacts of several fatty acids on myocellular insulin resistance were determined. Results In normal L6 cells, treatment with saturated palmitic or stearic acid alone decreased 2DG uptake, whereas unsaturated fatty acids did not. Moreover, co-treatment with oleic acid canceled the palmitic acid-induced decrease in 2DG uptake activity. Using the developed assay with palmitic acid-induced insulin-resistant L6 cells, we determined the effects of other unsaturated fatty acids. We found that arachidonic, eicosapentaenoic and docosahexaenoic acids improved palmitic acid-decreased 2DG uptake at lower concentrations than the other unsaturated fatty acids, including oleic acid, as 10 μM arachidonic acid showed similar effects to 750 μM oleic acid. Conclusions We have found that polyunsaturated fatty acids, in particular arachidonic and eicosapentaenoic acids prevent palmitic acid-induced myocellular insulin resistance.

  14. Identifying the receptor subtype selectivity of retinoid X and retinoic acid receptors via quantum mechanics.

    Science.gov (United States)

    Tsuji, Motonori; Shudo, Koichi; Kagechika, Hiroyuki

    2017-03-01

    Understanding and identifying the receptor subtype selectivity of a ligand is an important issue in the field of drug discovery. Using a combination of classical molecular mechanics and quantum mechanical calculations, this report assesses the receptor subtype selectivity for the human retinoid X receptor (hRXR) and retinoic acid receptor (hRAR) ligand-binding domains (LBDs) complexed with retinoid ligands. The calculated energies show good correlation with the experimentally reported binding affinities. The technique proposed here is a promising method as it reveals the origin of the receptor subtype selectivity of selective ligands.

  15. Retinol dehydrogenase-10 regulates pancreas organogenesis and endocrine cell differentiation via paracrine retinoic acid signalling

    DEFF Research Database (Denmark)

    Arregi, Igor; Climent, Maria; Iliev, Dobromir;

    2016-01-01

    Vitamin A-derived retinoic acid (RA) signals are critical for the development of several organs, including the pancreas. However, the tissue-specific control of RA synthesis in organ and cell lineage development has only poorly been addressed in vivo. Here we show that Retinol dehydrogenase-10 (Rdh...... and a hypoplastic ventral pancreas with retarded tubulogenesis and branching. Conditional disruption of Rdh10 from the endoderm caused increased mortality, reduced body weight and lowered blood glucose levels after birth. Endodermal Rdh10 deficiency led to a smaller dorsal pancreas with a reduced density of early...

  16. Are Gene Expression Microarray Analyses Reliable? A Review of Studies of Retinoic Acid Responsive Genes

    Institute of Scientific and Technical Information of China (English)

    Peter J. van der Spek; Andreas Kremer; Lynn Murry; Michael G. Walker

    2003-01-01

    Microarray analyses of gene expression are widely used, but reports of the same analyses by different groups give widely divergent results, and raise questions regarding reproducibility and reliability. We take as an example recent published reports on microarray experiments that were designed to identify retinoic acid responsive genes. These reports show substantial differences in their results. In this article, we review the methodology, results, and potential causes of differences in these applications of microarrays. Finally, we suggest practices to improve the reliability and reproducibility of microarray experiments.

  17. Are Gene Expression Microarray Analyses Reliable? A Review of Studies of Retinoic Acid Responsive Genes

    Institute of Scientific and Technical Information of China (English)

    PeterJ.vanderSpek; AndreasKremer; LynnMurry; MichaelG.Walker

    2003-01-01

    Microarray analyses of gene expression are widely used,but reports of the same analyses by different groups give widely divergent results,and raise questions regarding reproducibility and reliability.We take as an example recent published reports on microarray experiments that were designed to identify retinoic acid responsive genes.These reports show substantial differences in their results.In this article,we review the methodology,results,and potential causes of differences in these applications of microarrays.Finally,we suggest practices to improve the reliability and reproducibility of microarray experiments.

  18. Effect of CMC Molecular Weight on Acid-Induced Gelation of Heated WPI-CMC Soluble Complex.

    Science.gov (United States)

    Huan, Yan; Zhang, Sha; Vardhanabhuti, Bongkosh

    2016-02-01

    Acid-induced gelation properties of heated whey protein isolate (WPI) and carboxymethylcellulose (CMC) soluble complex were investigated as a function of CMC molecular weight (270, 680, and 750 kDa) and concentrations (0% to 0.125%). Heated WPI-CMC soluble complex with 6% protein was made by heating biopolymers together at pH 7.0 and 85 °C for 30 min and diluted to 5% protein before acid-induced gelation. Acid-induced gel formed from heated WPI-CMC complexes exhibited increased hardness and decreased water holding capacity with increasing CMC concentrations but gel strength decreased at higher CMC content. The highest gel strength was observed with CMC 750 k at 0.05%. Gels with low CMC concentration showed homogenous microstructure which was independent of CMC molecular weight, while increasing CMC concentration led to microphase separation with higher CMC molecular weight showing more extensive phase separation. When heated WPI-CMC complexes were prepared at 9% protein the acid gels showed improved gel hardness and water holding capacity, which was supported by the more interconnected protein network with less porosity when compared to complexes heated at 6% protein. It is concluded that protein concentration and biopolymer ratio during complex formation are the major factors affecting gel properties while the effect of CMC molecular weight was less significant.

  19. Arginine of retinoic acid receptor beta which coordinates with the carboxyl group of retinoic acid functions independent of the amino acid residues responsible for retinoic acid receptor subtype ligand specificity.

    Science.gov (United States)

    Zhang, Zeng Ping; Hutcheson, Juliet M; Poynton, Helen C; Gabriel, Jerome L; Soprano, Kenneth J; Soprano, Dianne Robert

    2003-01-15

    The biological actions of retinoic acid (RA) are mediated by retinoic acid receptors (RARalpha, RARbeta, and RARgamma) and retinoid X receptors (RXRalpha, RXRbeta, and RXRgamma). Consistent with the X-ray crystal structures of RARalpha and RARgamma, site-directed mutagenesis studies have demonstrated the importance of a conserved Arg residue (alphaArg(276), betaArg(269), and gammaArg(278)) for coordination with the carboxyl group of RA. However, mutation of Arg(269) to Ala in RARbeta causes only a 3- to 6-fold increase in the K(d) for RA and EC(50) in RA-dependent transcriptional transactivation assays while the homologous mutation in either RARalpha or RARgamma causes a 110-fold and a 45-fold increase in EC(50) value, respectively. To further investigate the nature of this difference, we prepared mutant RARs to determine the effect of conversion of betaR269A to a mutant which mimics either RARalpha ligand selectivity (betaA225S/R269A) or RARgamma ligand selectivity (betaI263M/R269A/V338A). Our results demonstrate that in RARbeta mutants that acquire either RARalpha or RARgamma ligand specificity the Arg(269) position responsible for coordination with the carboxyl group of retinoids continued to function like that of RARbeta. Furthermore, three mutant receptors (betaA225S/R269A, betaA225S/F279, and alphaF286A) were found to have a greater than wild-type affinity for the RARalpha-selective ligand Am580. Finally, a homology-based computer model of the ligand binding domain (LBD) of RARbeta and the X-ray crystal structures of the LBD of both RARalpha and RARgamma are used to describe potential mechanisms responsible for the increased affinity of some mutants for Am580 and for the difference in the effect of mutation of Arg(269) in RARbeta compared to its homologous Arg in RARalpha and RARgamma.

  20. Role of Vitamin A/Retinoic Acid in Regulation of Embryonic and Adult Hematopoiesis

    Directory of Open Access Journals (Sweden)

    Ana Cañete

    2017-02-01

    Full Text Available Vitamin A is an essential micronutrient throughout life. Its physiologically active metabolite retinoic acid (RA, acting through nuclear retinoic acid receptors (RARs, is a potent regulator of patterning during embryonic development, as well as being necessary for adult tissue homeostasis. Vitamin A deficiency during pregnancy increases risk of maternal night blindness and anemia and may be a cause of congenital malformations. Childhood Vitamin A deficiency can cause xerophthalmia, lower resistance to infection and increased risk of mortality. RA signaling appears to be essential for expression of genes involved in developmental hematopoiesis, regulating the endothelial/blood cells balance in the yolk sac, promoting the hemogenic program in the aorta-gonad-mesonephros area and stimulating eryrthropoiesis in fetal liver by activating the expression of erythropoietin. In adults, RA signaling regulates differentiation of granulocytes and enhances erythropoiesis. Vitamin A may facilitate iron absorption and metabolism to prevent anemia and plays a key role in mucosal immune responses, modulating the function of regulatory T cells. Furthermore, defective RA/RARα signaling is involved in the pathogenesis of acute promyelocytic leukemia due to a failure in differentiation of promyelocytes. This review focuses on the different roles played by vitamin A/RA signaling in physiological and pathological mouse hematopoiesis duddurring both, embryonic and adult life, and the consequences of vitamin A deficiency for the blood system.

  1. Tbx1 and Brn4 regulate retinoic acid metabolic genes during cochlear morphogenesis

    Directory of Open Access Journals (Sweden)

    Braunstein Evan M

    2009-05-01

    Full Text Available Abstract Background In vertebrates, the inner ear is comprised of the cochlea and vestibular system, which develop from the otic vesicle. This process is regulated via inductive interactions from surrounding tissues. Tbx1, the gene responsible for velo-cardio-facial syndrome/DiGeorge syndrome in humans, is required for ear development in mice. Tbx1 is expressed in the otic epithelium and adjacent periotic mesenchyme (POM, and both of these domains are required for inner ear formation. To study the function of Tbx1 in the POM, we have conditionally inactivated Tbx1 in the mesoderm while keeping expression in the otic vesicle intact. Results Conditional mutants (TCre-KO displayed malformed inner ears, including a hypoplastic otic vesicle and a severely shortened cochlear duct, indicating that Tbx1 expression in the POM is necessary for proper inner ear formation. Expression of the mesenchyme marker Brn4 was also lost in the TCre-KO. Brn4-;Tbx1+/-embryos displayed defects in growth of the distal cochlea. To identify a potential signal from the POM to the otic epithelium, expression of retinoic acid (RA catabolizing genes was examined in both mutants. Cyp26a1 expression was altered in the TCre-KO, while Cyp26c1 showed reduced expression in both TCre-KO and Brn4-;Tbx1+/- embryos. Conclusion These results indicate that Tbx1 expression in the POM regulates cochlear outgrowth potentially via control of local retinoic acid activity.

  2. MicroRNA 146 (Mir146) modulates spermatogonial differentiation by retinoic acid in mice.

    Science.gov (United States)

    Huszar, Jessica M; Payne, Christopher J

    2013-01-01

    Impaired biogenesis of microRNAs disrupts spermatogenesis and leads to infertility in male mice. Spermatogonial differentiation is a key step in spermatogenesis, yet the mechanisms that control this event remain poorly defined. In this study, we discovered microRNA 146 (Mir146) to be highly regulated during spermatogonial differentiation, a process dependent on retinoic acid (RA) signaling. Mir146 transcript levels were diminished nearly 180-fold in differentiating spermatogonia when compared with undifferentiated spermatogonia. Luciferase assays revealed the direct binding of Mir146 to the 3' untranslated region of the mediator complex subunit 1 (Med1), a coregulator of retinoid receptors (RARs and RXRs). Overexpression of Mir146 in cultured undifferentiated spermatogonia reduced Med1 transcript levels, as well as those of differentiation marker kit oncogene (Kit). MED1 protein was also diminished. Conversely, inhibition of Mir146 increased the levels of Kit. When undifferentiated spermatogonia were exposed to RA, Mir146 was downregulated along with a marker for undifferentiated germ cells, zinc finger and BTB domain containing 16 (Zbtb16; Plzf); Kit was upregulated. Overexpression of Mir146 in RA-treated spermatogonia inhibited the upregulation of Kit, stimulated by retinoic acid gene 8 (Stra8), and spermatogenesis- and oogenesis-specific basic helix-loop-helix 2 (Sohlh2). Inhibition of Mir146 in RA-treated spermatogonia greatly enhanced the upregulation of these genes. We conclude that Mir146 modulates the effects of RA on spermatogonial differentiation.

  3. MicroRNA 146 (Mir146) Modulates Spermatogonial Differentiation by Retinoic Acid in Mice1

    Science.gov (United States)

    Huszar, Jessica M.; Payne, Christopher J.

    2012-01-01

    ABSTRACT Impaired biogenesis of microRNAs disrupts spermatogenesis and leads to infertility in male mice. Spermatogonial differentiation is a key step in spermatogenesis, yet the mechanisms that control this event remain poorly defined. In this study, we discovered microRNA 146 (Mir146) to be highly regulated during spermatogonial differentiation, a process dependent on retinoic acid (RA) signaling. Mir146 transcript levels were diminished nearly 180-fold in differentiating spermatogonia when compared with undifferentiated spermatogonia. Luciferase assays revealed the direct binding of Mir146 to the 3′ untranslated region of the mediator complex subunit 1 (Med1), a coregulator of retinoid receptors (RARs and RXRs). Overexpression of Mir146 in cultured undifferentiated spermatogonia reduced Med1 transcript levels, as well as those of differentiation marker kit oncogene (Kit). MED1 protein was also diminished. Conversely, inhibition of Mir146 increased the levels of Kit. When undifferentiated spermatogonia were exposed to RA, Mir146 was downregulated along with a marker for undifferentiated germ cells, zinc finger and BTB domain containing 16 (Zbtb16; Plzf); Kit was upregulated. Overexpression of Mir146 in RA-treated spermatogonia inhibited the upregulation of Kit, stimulated by retinoic acid gene 8 (Stra8), and spermatogenesis- and oogenesis-specific basic helix-loop-helix 2 (Sohlh2). Inhibition of Mir146 in RA-treated spermatogonia greatly enhanced the upregulation of these genes. We conclude that Mir146 modulates the effects of RA on spermatogonial differentiation. PMID:23221399

  4. Retinoic acid receptor regulation of epimorphic and homeostatic regeneration in the axolotl.

    Science.gov (United States)

    Nguyen, Matthew; Singhal, Pankhuri; Piet, Judith W; Shefelbine, Sandra J; Maden, Malcolm; Voss, S Randal; Monaghan, James R

    2017-02-15

    Salamanders are capable of regenerating amputated limbs by generating a mass of lineage-restricted cells called a blastema. Blastemas only generate structures distal to their origin unless treated with retinoic acid (RA), which results in proximodistal (PD) limb duplications. Little is known about the transcriptional network that regulates PD duplication. In this study, we target specific retinoic acid receptors (RARs) to either PD duplicate (RA treatment or RARγ agonist) or truncate (RARβ antagonist) regenerating limbs. RARE-EGFP reporter axolotls showed divergent reporter activity in limbs undergoing PD duplication versus truncation, suggesting differences in patterning and skeletal regeneration. Transcriptomics identified expression patterns that explain PD duplication, including upregulation of proximal homeobox gene expression and silencing of distal-associated genes, whereas limb truncation was associated with disrupted skeletal differentiation. RARβ antagonism in uninjured limbs induced a loss of skeletal integrity leading to long bone regression and loss of skeletal turnover. Overall, mechanisms were identified that regulate the multifaceted roles of RARs in the salamander limb including regulation of skeletal patterning during epimorphic regeneration, skeletal tissue differentiation during regeneration, and homeostatic regeneration of intact limbs.

  5. Role of Vitamin A/Retinoic Acid in Regulation of Embryonic and Adult Hematopoiesis

    Science.gov (United States)

    Cañete, Ana; Cano, Elena; Muñoz-Chápuli, Ramón; Carmona, Rita

    2017-01-01

    Vitamin A is an essential micronutrient throughout life. Its physiologically active metabolite retinoic acid (RA), acting through nuclear retinoic acid receptors (RARs), is a potent regulator of patterning during embryonic development, as well as being necessary for adult tissue homeostasis. Vitamin A deficiency during pregnancy increases risk of maternal night blindness and anemia and may be a cause of congenital malformations. Childhood Vitamin A deficiency can cause xerophthalmia, lower resistance to infection and increased risk of mortality. RA signaling appears to be essential for expression of genes involved in developmental hematopoiesis, regulating the endothelial/blood cells balance in the yolk sac, promoting the hemogenic program in the aorta-gonad-mesonephros area and stimulating eryrthropoiesis in fetal liver by activating the expression of erythropoietin. In adults, RA signaling regulates differentiation of granulocytes and enhances erythropoiesis. Vitamin A may facilitate iron absorption and metabolism to prevent anemia and plays a key role in mucosal immune responses, modulating the function of regulatory T cells. Furthermore, defective RA/RARα signaling is involved in the pathogenesis of acute promyelocytic leukemia due to a failure in differentiation of promyelocytes. This review focuses on the different roles played by vitamin A/RA signaling in physiological and pathological mouse hematopoiesis duddurring both, embryonic and adult life, and the consequences of vitamin A deficiency for the blood system. PMID:28230720

  6. Processive pulses of retinoic acid propel asynchronous and continuous murine sperm production.

    Science.gov (United States)

    Hogarth, Cathryn A; Arnold, Samuel; Kent, Travis; Mitchell, Debra; Isoherranen, Nina; Griswold, Michael D

    2015-02-01

    The asynchronous cyclic nature of spermatogenesis is essential for continual sperm production and is one of the hallmarks of mammalian male fertility. While various mRNA and protein localization studies have indirectly implicated changing retinoid levels along testis tubules, no quantitative evidence for these changes across the cycle of the seminiferous epithelium currently exists. This study utilized a unique mouse model of induced synchronous spermatogenesis, localization of the retinoid-signaling marker STRA8, and sensitive quantification of retinoic acid concentrations to determine whether there are fluctuations in retinoid levels at each of the individual stages of germ cell differentiation and maturation to sperm. These data show that processive pulses of retinoic acid are generated during spermatogonial differentiation and are the likely trigger for cyclic spermatogenesis and allow us, for the first time, to understand how the cycle of the seminiferous epithelium is generated and maintained. In addition, this study represents the first direct quantification of a retinoid gradient controlling cellular differentiation in a postnatal tissue.

  7. Retinoic acid and glycolic acid combination in the treatment of acne scars

    Directory of Open Access Journals (Sweden)

    B S Chandrashekar

    2015-01-01

    Full Text Available Introduction: Acne is a prevalent condition in society affecting nearly 80-90% of adolescents often resulting in secondary damage in the form of scarring. Retinoic acid (RA is said to improve acne scars and reduce postinflammatory hyperpigmentation while glycolic acid (GA is known for its keratolytic properties and its ability to reduce atrophic acne scars. There are studies exploring the combined effect of retinaldehyde and GA combination with positive results while the efficacy of retinoic acid and GA (RAGA combination remains unexplored. Aim: The aim of this study remains to retrospectively assess the efficacy of RAGA combination on acne scars in patients previously treated for active acne. Materials and Methods: A retrospective assessment of 35 patients using topical RAGA combination on acne scars was done. The subjects were 17-34 years old and previously treated for active acne. Case records and photographs of each patient were assessed and the acne scars were graded as per Goodman and Baron′s global scarring grading system (GSGS, before the start and after 12 weeks of RAGA treatment. The differences in the scar grades were noted to assess the improvement. Results: At the end of 12 weeks, significant improvement in acne scars was noticed in 91.4% of the patients. Conclusion: The RAGA combination shows efficacy in treating acne scars in the majority of patients, minimizing the need of procedural treatment for acne scars.

  8. Comparative effects of retinoic acid or glycolic acid vehiculated in different topical formulations.

    Science.gov (United States)

    Maia Campos, Patrícia Maria Berardo Gonçalves; Gaspar, Lorena Rigo; Gonçalves, Gisele Mara Silva; Pereira, Lúcia Helena Terenciane Rodrigues; Semprini, Marisa; Lopes, Ruberval Armando

    2015-01-01

    Retinoids and hydroxy acids have been widely used due to their effects in the regulation of growth and in the differentiation of epithelial cells. However, besides their similar indication, they have different mechanisms of action and thus they may have different effects on the skin; in addition, since the topical formulation efficiency depends on vehicle characteristics, the ingredients of the formulation could alter their effects. Thus the objective of this study was to compare the effects of retinoic acid (RA) and glycolic acid (GA) treatment on the hairless mouse epidermis thickness and horny layer renewal when added in gel, gel cream, or cream formulations. For this, gel, gel cream, and cream formulations (with or without 6% GA or 0.05% RA) were applied in the dorsum of hairless mice, once a day for seven days. After that, the skin was analyzed by histopathologic, morphometric, and stereologic techniques. It was observed that the effects of RA occurred independently from the vehicle, while GA had better results when added in the gel cream and cream. Retinoic acid was more effective when compared to glycolic acid, mainly in the cell renewal and the exfoliation process because it decreased the horny layer thickness.

  9. Comparative Effects of Retinoic Acid or Glycolic Acid Vehiculated in Different Topical Formulations

    Directory of Open Access Journals (Sweden)

    Patrícia Maria Berardo Gonçalves Maia Campos

    2015-01-01

    Full Text Available Retinoids and hydroxy acids have been widely used due to their effects in the regulation of growth and in the differentiation of epithelial cells. However, besides their similar indication, they have different mechanisms of action and thus they may have different effects on the skin; in addition, since the topical formulation efficiency depends on vehicle characteristics, the ingredients of the formulation could alter their effects. Thus the objective of this study was to compare the effects of retinoic acid (RA and glycolic acid (GA treatment on the hairless mouse epidermis thickness and horny layer renewal when added in gel, gel cream, or cream formulations. For this, gel, gel cream, and cream formulations (with or without 6% GA or 0.05% RA were applied in the dorsum of hairl