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Sample records for affects aromatase inhibitor

  1. Update on Aromatase Inhibitors

    Directory of Open Access Journals (Sweden)

    Seifert-Klauss V

    2015-01-01

    Full Text Available Aromatase inhibitors (AI block the last phase of estrogen production in many types of tissues which express the enzym aromatase, among them muscle, liver, adrenal, brain and fat. The enzyme catalyzes the last step of the biosynthesis of the estrogens, i. e. the aromatisation of testosterone to estradiol and of androstendion to estrone. Aromatase is localized in the membrane of the endoplasmatic reticulum and is also produced in the placenta and the gonads. Mutations in the gene CYP19A1, which codes for aromatase, can lead either to lack or excess of aromatase. Gene polymorphisms also influence the amount of bioavailable estrogen and bone density.br Indications: AI are approved for the treatment of postmenopausal women with hormone receptor positive breast cancer, both in the adjuvant setting as well as after recurrence and in progressive disease. In premenopausal and in perimenopausal women AI cause an increased sensitivity of the ovaries to follicle stimulating hormone (FSH and can thereby lead to a boosted estrogen answer – this effect is particularly pronounced in early perimenopausal women – so that these situations demand a combination with GnRH-analogue if AI treatment is to be initiated. Alternatively, tamoxifene may be used in premenopausal patients, with or without GnRH analogues. Treatment of premenopausal patients with hormone receptor positive breast cancer with aromatase inhibiting therapy alone constitutes an absolute contraindication. Aromatase inhibitors do not lead to estrogen receptor downregulation or block the receptor such as tamoxifene. An exceptional application is the application in reproductive medicine in women who do not have hormone receptor positive breast cancer: because of the higher sensitivity induced by AI-co-therapy, FSH-doses and -costs for assisted reproduction are reduced, and ovarian hyperstimulation syndrome (OHSS may be avoided. For premenopausal diseases which are said to be positively affected by

  2. Aromatase inhibitors in the treatment of endometriosis.

    Science.gov (United States)

    Słopień, Radosław; Męczekalski, Błażej

    2016-03-01

    Endometriosis is a chronic inflammatory condition in which foci of endometrial tissue grow outside of the uterine cavity. Endometriosis was estimated to affect 176 million women of childbearing potential all over the world in 2010. The presence of extrauterine endometrial tissue is associated with pain and infertility. Typical symptoms of endometriosis include dysmenorrhoea, dyspareunia, heavy menstrual periods (menorrhagia), pelvic pain that is not related to menstrual cycles, dysuria, and chronic fatigue. Medical treatments for endometriosis include combined oral contraceptive pills, danazol, gestrinone, medroxyprogesterone acetate, and gonadotropin-releasing hormone agonists (aGnRHs). A new class of medications called aromatase inhibitors has been identified in recent years as potential therapeutic agents for endometriosis. This article provides general information about aromatase inhibitors, their use in gynaecology, and their adverse effects. In particular, the paper discusses the use of aromatase inhibitors in the treatment of endometriosis in postmenopausal women. Unlike oral contraceptives, gestagens, aGnRHs, and danazol, which suppress ovarian oestrogen synthesis, aromatase inhibitors inhibit mainly extra-ovarian synthesis of oestrogens. Therefore, the use of aromatase inhibitors seems to be particularly relevant in older patients, as most of the body's oestrogen is produced outside the ovaries after menopause. The paper discusses also the use of aromatase inhibitors in the treatment of pain associated with endometriosis and infertility caused by endometriosis. PMID:27095958

  3. Aromatase inhibitors in the treatment of endometriosis

    Science.gov (United States)

    Męczekalski, Błażej

    2016-01-01

    Endometriosis is a chronic inflammatory condition in which foci of endometrial tissue grow outside of the uterine cavity. Endometriosis was estimated to affect 176 million women of childbearing potential all over the world in 2010. The presence of extrauterine endometrial tissue is associated with pain and infertility. Typical symptoms of endometriosis include dysmenorrhoea, dyspareunia, heavy menstrual periods (menorrhagia), pelvic pain that is not related to menstrual cycles, dysuria, and chronic fatigue. Medical treatments for endometriosis include combined oral contraceptive pills, danazol, gestrinone, medroxyprogesterone acetate, and gonadotropin-releasing hormone agonists (aGnRHs). A new class of medications called aromatase inhibitors has been identified in recent years as potential therapeutic agents for endometriosis. This article provides general information about aromatase inhibitors, their use in gynaecology, and their adverse effects. In particular, the paper discusses the use of aromatase inhibitors in the treatment of endometriosis in postmenopausal women. Unlike oral contraceptives, gestagens, aGnRHs, and danazol, which suppress ovarian oestrogen synthesis, aromatase inhibitors inhibit mainly extra-ovarian synthesis of oestrogens. Therefore, the use of aromatase inhibitors seems to be particularly relevant in older patients, as most of the body's oestrogen is produced outside the ovaries after menopause. The paper discusses also the use of aromatase inhibitors in the treatment of pain associated with endometriosis and infertility caused by endometriosis. PMID:27095958

  4. Molecular Docking of Aromatase Inhibitors

    Directory of Open Access Journals (Sweden)

    Virapong Prachayasittikul

    2011-04-01

    Full Text Available Aromatase is an enzyme that plays a critical role in the development of estrogen receptor positive breast cancer. As aromatase catalyzes the aromatization of androstenedione to estrone, a naturally occurring estrogen, it is a promising drug target for therapeutic management. The undesirable effects found in aromatase inhibitors (AIs that are in clinical use necessitate the discovery of novel AIs with higher selectivity, less toxicity and improving potency. In this study, we elucidate the binding mode of all three generations of AI drugs to the crystal structure of aromatase by means of molecular docking. It was demonstrated that the docking protocol could reliably reproduce the interaction of aromatase with its substrate with an RMSD of 1.350 Å. The docking study revealed that polar (D309, T310, S478 and M374, aromatic (F134, F221 and W224 and non-polar (A306, A307, V370, L372 and L477 residues were important for interacting with the AIs. The insights gained from the study herein have great potential for the design of novel AIs.

  5. Natural Products as Aromatase Inhibitors

    OpenAIRE

    Balunas, Marcy J.; Su, Bin; Brueggemeier, Robert W.; Kinghorn, A. Douglas

    2008-01-01

    With the clinical success of several synthetic aromatase inhibitors (AIs) in the treatment of postmenopausal estrogen receptor-positive breast cancer, researchers have also been investigating also the potential of natural products as AIs. Natural products from terrestrial and marine organisms provide a chemically diverse array of compounds not always available through current synthetic chemistry techniques. Natural products that have been used traditionally for nutritional or medicinal purpos...

  6. Aromatase inhibitors for subfertile women with polycystic ovary syndrome (Review)

    NARCIS (Netherlands)

    Franik, S.; Kremer, J.A.M.; Nelen, W.L.D.M.; Farquhar, C.

    2014-01-01

    BACKGROUND: Polycystic ovary syndrome (PCOS) is the most common cause of infrequent periods (oligomenorrhoea) and absence of periods (amenorrhoea). It affects about 4% to 8% of women worldwide and often leads to anovulatory subfertility. Aromatase inhibitors (AIs) are a novel class of drugs that wer

  7. Pharmacogenomics of tamoxifen and aromatase inhibitors.

    Science.gov (United States)

    Ingle, James N

    2008-02-01

    In selection of therapy for women with breast cancer, the focus has been almost exclusively on the characteristics of the tumor, eg, estrogen receptor (ER) and HER-2. Until recently, essentially no attention has been paid to the host and her genetic makeup as it relates to the metabolism of different drugs. The first real clinical application of pharmacogenetics in breast cancer management relates to tamoxifen's biotransformation to active anticancer metabolites. New information has arisen on the metabolism of tamoxifen to the active metabolite, 4 hydroxy-N-desmethyl-tamoxifen (endoxifen). Endoxifen is a metabolite with antitumor activity and affinity for the ER that is similar to 4-hydroxy-tamoxifen, but 1 that is normally present in substantially higher concentrations. CYP2D6 plays a central role in the metabolism to endoxifen and 1 published study shows that genotypic differences in CYP2D6 and use of CYP2D6 inhibitors has an impact on outcomes of women treated with tamoxifen. The aromatase inhibitors represent a major class of drugs in the armamentarium against breast cancer. The aromatase gene has been resequenced and functional genomics have been performed on the identified nonsynonymous coding single nucleotide polymorphisms showing significant decreases in levels of activity. These findings are consistent with a hypothesis that genetic variation in the CYP19 gene might be important in the activity of aromatase inhibitors. Currently, the emphasis is on examining multiple genes (thus pharmacogenomics) in pharmacodynamic and pharmacokinetic pathways in women receiving aromatase inhibitors for breast cancer. PMID:18072234

  8. Aromatase inhibitors and anti-synthetase syndrome.

    Science.gov (United States)

    Mascella, Fabio; Gianni, Lorenzo; Affatato, Alessandra; Fantini, Manuela

    2016-09-01

    Adjuvant therapy in postmenopausal women with endocrine-responsive breast cancer (BC) is actually centered on the use of anti-aromatase inhibitors (AI). Several reports, however, are emerging in literature associating the use of this drugs to rheumatic disorders. This case report describes the first case of anti-synthetase syndrome diagnosis after treatment with anti-estrogen agents in a patient with pre-existing rheumatoid arthritis. PMID:27225465

  9. Aromatase inhibitors for subfertile women with polycystic ovary syndrome (Review)

    OpenAIRE

    Franik, S.; Kremer, J.A.M.; Nelen, W.L.D.M.; Farquhar, C

    2014-01-01

    BACKGROUND: Polycystic ovary syndrome (PCOS) is the most common cause of infrequent periods (oligomenorrhoea) and absence of periods (amenorrhoea). It affects about 4% to 8% of women worldwide and often leads to anovulatory subfertility. Aromatase inhibitors (AIs) are a novel class of drugs that were introduced for ovulation induction in 2001. Over the last ten years clinical trials have reached differing conclusions as to whether the AI letrozole is at least as effective as the first-line tr...

  10. Aromatase inhibitor strategies in metastatic breast cancer

    Directory of Open Access Journals (Sweden)

    Heather L McArthur

    2009-07-01

    Full Text Available Heather L McArthur, Patrick G MorrisBreast Cancer Medicine Service, Department of Medicine, Memorial Sloan-Kettering Cancer Center, New York, NY, USAAbstract: Despite ongoing therapeutic innovations, metastatic breast cancer (MBC remains a treatable but incurable disease. In the developed world, a diagnosis of MBC without a preceding diagnosis of early stage disease is a rare event. However, approximately one-third of women with early stage breast cancer ultimately experience a distant recurrence. Because the majority of breast cancers express estrogen and/or progesterone receptors and are accordingly considered hormone-sensitive, therapeutic strategies that interfere with hormone-mediated tumorigenesis have been a cornerstone of the breast cancer management paradigm for decades. Historically, the selective estrogen receptor modulator tamoxifen has been the most extensively studied and widely used hormone maneuver in breast cancer. However, a recent therapeutic innovation, namely the successful development of third-generation aromatase inhibitors (AIs, has had a dramatic impact on the treatment paradigm for women with hormone-sensitive MBC. Because of the demonstrated efficacy in postmenopausal breast cancer patients, the generally favorable side-effect profile, and the convenience of oral administration, AIs are now in widespread clinical use. Currently, there are three clinically available third-generation AIs: two reversible, nonsteroidal AIs, letrozole and anastrozole; and one irreversible, steroidal AI, exemestane. All three agents are at least as efficacious as tamoxifen as monotherapy for postmenopausal women with hormone-sensitive MBC. Current clinical research aims to improve upon existing strategies by evaluating AIs in combination with systemic chemotherapy regimens and/or novel targeted agents. It is hoped that these therapeutic innovations will lead to ongoing improvements in quality of life parameters and ideally survival for women

  11. Committee Opinion No. 663: Aromatase Inhibitors in Gynecologic Practice.

    Science.gov (United States)

    2016-06-01

    Aromatase inhibitors have been used for the treatment of breast cancer, ovulation induction, endometriosis, and other estrogen-modulated conditions. For women with breast cancer, bone mineral density screening is recommended with long-term aromatase inhibitor use because of risk of osteoporosis due to estrogen deficiency. Based on long-term adverse effects and complication safety data, when compared with tamoxifen, aromatase inhibitors are associated with a reduced incidence of thrombosis, endometrial cancer, and vaginal bleeding. For women with polycystic ovary syndrome and a body mass index greater than 30, letrozole should be considered as first-line therapy for ovulation induction because of the increased live birth rate compared with clomiphene citrate. Lifestyle changes that result in weight loss should be strongly encouraged. Aromatase inhibitors are a promising therapeutic option that may be helpful for the management of endometriosis-associated pain in combination therapy with progestins. PMID:27214191

  12. Committee Opinion No. 663 Summary: Aromatase Inhibitors in Gynecologic Practice.

    Science.gov (United States)

    2016-06-01

    Aromatase inhibitors have been used for the treatment of breast cancer, ovulation induction, endometriosis, and other estrogen-modulated conditions. For women with breast cancer, bone mineral density screening is recommended with long-term aromatase inhibitor use because of risk of osteoporosis due to estrogen deficiency. Based on long-term adverse effects and complication safety data, when compared with tamoxifen, aromatase inhibitors are associated with a reduced incidence of thrombosis, endometrial cancer, and vaginal bleeding. For women with polycystic ovary syndrome and a body mass index greater than 30, letrozole should be considered as first-line therapy for ovulation induction because of the increased live birth rate compared with clomiphene citrate. Lifestyle changes that result in weight loss should be strongly encouraged. Aromatase inhibitors are a promising therapeutic option that may be helpful for the management of endometriosis-associated pain in combination therapy with progestins. PMID:27214185

  13. Aromatase inhibitors and antiepileptic drugs: a computational systems biology analysis

    Directory of Open Access Journals (Sweden)

    Mustata Gabriela

    2011-06-01

    Full Text Available Abstract Background The present study compares antiepileptic drugs and aromatase (CYP19 inhibitors for chemical and structural similarity. Human aromatase is well known as an important pharmacological target in anti-breast cancer therapy, but recent research demonstrates its role in epileptic seizures, as well. The current antiepileptic treatment methods cause severe side effects that endanger patient health and often preclude continued use. As a result, less toxic and more tolerable antiepileptic drugs (AEDs are needed, especially since every individual responds differently to given treatment options. Methods Through a pharmacophore search, this study shows that a model previously designed to search for new classes of aromatase inhibitors is able to identify antiepileptic drugs from the set of drugs approved by the Food and Drug Administration. Chemical and structural similarity analyses were performed using five potent AIs, and these studies returned a set of AEDs that the model identifies as hits. Results The pharmacophore model returned 73% (19 out of 26 of the drugs used specifically to treat epilepsy and approximately 82% (51 out of 62 of the compounds with anticonvulsant properties. Therefore, this study supports the possibility of identifying AEDs with a pharmacophore model that had originally been designed to identify new classes of aromatase inhibitors. Potential candidates for anticonvulsant therapy identified in this manner are also reported. Additionally, the chemical and structural similarity between antiepileptic compounds and aromatase inhibitors is proved using similarity analyses. Conclusions This study demonstrates that a pharmacophore search using a model based on aromatase inhibition and the enzyme's structural features can be used to screen for new candidates for antiepileptic therapy. In fact, potent aromatase inhibitors and current antiepileptic compounds display significant - over 70% - chemical and structural similarity

  14. Aromatase inhibitors in stimulated IVF cycles

    Directory of Open Access Journals (Sweden)

    Tournaye Herman

    2011-06-01

    Full Text Available Abstract Aromatase inhibitors have been introduced as a new treatment modality that could challenge clomiphene citrate as an ovulation induction regiment in patients with PCOS. Although several randomized trials have been conducted regarding their use as ovulation induction agents, only few trials are available regarding their efficacy in IVF stimulated cycles. Current available evidence support that letrozole may have a promising role in stimulated IVF cycles, either when administered during the follicular phase for ovarian stimulation. Especially for women with poor ovarian response, letrozole appears to have the potential to increase clinical pregnancy rates when combined with gonadotropins, whereas at the same time reduces the total gonadotropin dose required for ovarian stimulation. However, given that in all of the trials letrozole has been administered in GnRH antagonist cycles, it is intriguing to test in the future how it may perform when used in GnRH agonist cycles. Finally administration of letrozole during luteal phase in IVF cycles offers another treatment modality for patients at high risk for OHSS taking into account that it drastically reduces estradiol levels

  15. Two aromatase inhibitors inhibit the ability of a third to promote mating in male rats.

    Science.gov (United States)

    Yahr, Pauline

    2015-09-01

    Aromatase, the enzyme that aromatizes androstenedione (A) to estrone and testosterone (T) to estradiol (E), affects androgen control of male sex behavior in many vertebrates. In male monkeys, rats and quail, E mimics the ability of T to promote mating, and aromatase inhibitors block mating induced by T but not E. Aromatase inhibitors include androgens with different A-rings than T and A, e.g., 1,4,6-androstatriene-3,17-dione (ATD), azoles, e.g., fadrozole, and androgens α-halogenated at carbon 6, e.g., 6α-bromoA, 6α-fluoroA and 6α-fluoroT. 6α-FluoroT is the only 6α-halogenated androgen studied in regard to mating. It promotes mating in male rats and quail and was studied, before it was known to inhibit aromatase, because it cannot be aromatized yet has the same A-ring as T. 6α-FluoroT might promote mating by binding estrogen receptors (ER) directly, i.e., unassisted, or by metabolism to an androgen that binds ER. Since neither process would require aromatase, this study tested both hypotheses by determining how mating induced in castrated male rats by 6α-fluoroT is affected by ATD and fadrozole. Both aromatase inhibitors inhibited the effects of 6α-fluoroT on mating. Thus, 6α-fluoroT does not promote mating by direct ER binding or metabolism to another androgen. Since aromatase underlies a process in which 6α-fluoroT, unlike most nonaromatizable androgens, mimics T effects on male sex behavior, the process must involve a feature that 6α-fluoroT shares with T but not other nonaromatizable androgens. A-ring structure is a candidate. A hypothesis is also offered for how aromatase may participate without aromatizing the androgen. PMID:26232614

  16. Potential role of aromatase inhibitors in the treatment of endometriosis

    Directory of Open Access Journals (Sweden)

    Abu Hashim H

    2014-07-01

    Full Text Available Hatem Abu HashimDepartment of Obstetrics and Gynecology, Faculty of Medicine, Mansoura University, Mansoura, EgyptAbstract: Endometriosis is an estrogen-dependent chronic inflammatory disease affecting 5%–10% of reproductive-age women, with a prevalence of 5%–50% in infertile women and >33% of women with chronic pelvic pain. Third-generation aromatase inhibitors (AIs are approved adjuvants for the treatment of estrogen receptor-positive breast cancer. Molecular studies have revealed the presence of aromatase P450, the key enzyme in the biosynthesis of ovarian estradiol, inside the endometriotic tissue, indicating local synthesis of estradiol. Thereby, AIs represent an appealing medical option for the management of different aspects of this enigmatic disease, especially pelvic pain and infertility. Accordingly, this review aims to evaluate the potential role of AIs in the treatment of endometriosis-associated symptoms, mainly pain and infertility. Notably, several studies have demonstrated that the combination of AIs with conventional therapy as oral contraceptive pills, progestins, or gonadotropin-releasing hormone analogs can be used to control endometriosis-associated pain and pain recurrence in premenopausal women, particularly those with pain due to rectovaginal endometriosis refractory to other medical or surgical treatment. Some case reports have shown promising results in the treatment of postmenopausal endometriosis as first-line treatment, when surgery is contraindicated, or as second-line treatment in the case of postoperative recurrence. Third-generation AIs, especially letrozole, have challenged clomiphene citrate as an ovulation-induction agent in patients with polycystic ovary syndrome and in cases of unexplained infertility. However, few studies are available regarding the use of AIs to treat endometriosis-associated infertility. Therefore, larger multicenter randomized trials using AIs for the treatment of endometriosis

  17. Which patients benefit most from adjuvant aromatase inhibitors?

    DEFF Research Database (Denmark)

    Viale, G; Regan, M M; Dell'Orto, P;

    2011-01-01

    On average, aromatase inhibitors are better than tamoxifen when used as initial or sequential therapy for postmenopausal women with endocrine-responsive early breast cancer. Because there may be contraindications to their use based on side-effects or cost, we investigated subgroups in which...

  18. Novel inhibitor discovery against aromatase through virtual screening and molecular dynamic simulation

    OpenAIRE

    Asadabadi, Ebrahim Barzegari; Chupani, Latifeh; Jamalan, Mostafa; Mirzaie, Sako; Shahverdi, Ahmad Reza

    2013-01-01

    Inhibition of aromatase (CYTP450) as a key enzyme in the estrogen biosynthesis could result in regression of estrogen-dependent tumors and even preventing the promotion of breast cancer. Although today potent steroid and non-steroid inhibitors of aromatase are available, isoflavanone derivatives as natural compounds with least side effects have been described as the candidate for a new generation of aromatase inhibitors. 2a as an isoflavanone derivative is the most potent inhibitor of arom...

  19. Aromatase inhibitors in the treatment of endometriosis

    OpenAIRE

    Słopień, Radosław; Męczekalski, Błażej

    2016-01-01

    Endometriosis is a chronic inflammatory condition in which foci of endometrial tissue grow outside of the uterine cavity. Endometriosis was estimated to affect 176 million women of childbearing potential all over the world in 2010. The presence of extrauterine endometrial tissue is associated with pain and infertility. Typical symptoms of endometriosis include dysmenorrhoea, dyspareunia, heavy menstrual periods (menorrhagia), pelvic pain that is not related to menstrual cycles, dysuria, and c...

  20. Aromatase inhibitors in the treatment of deep endometriosis

    Directory of Open Access Journals (Sweden)

    Simone Ferrero

    2009-09-01

    Full Text Available Recent case reports and pilot studies suggested that aromatase inhibitors might be effective in treating pain symptoms related to the presence of endometriosis. We present the case of a 32-year-old woman who suffered dysmenorrhea, dyspareunia, chronic pelvic pain, and dyschezia caused by rectovaginal endometriosis. Pain symptoms recurred after treatment with the oral contraceptive pill; the patient refused surgery. Therefore a double-drug regimen including letrozole (2.5 mg/day and norethisterone acetate (2.5 mg/day was offered to the patient. The scheduled length of treatment was six months. This double-drug regimen determined a quick and significant improvement in all pain symptoms. During treatment, the patient complained mild arthralgia. After the interruption of treatment, pain symptoms quickly recurred and at 6-month follow-up their intensity was similar to baseline values. Operative laparoscopy was performed, the presence of rectovaginal endometriosis was confirmed and all visible endometriotic lesions were excised. Aromatase inhibitors might be offered when pain symptoms caused by endometriosis persist during the administration of other hormonal therapies and the patient refuses surgery. However, women must be informed that these drugs determine only a temporary relief of pain symptoms and might cause adverse effects (such as arthralgia.

  1. A feasibility study of a Nordic walking intervention for women experiencing aromatase inhibitor associated arthralgia

    OpenAIRE

    Fields, Jo

    2015-01-01

    Background: Women taking AIs (Aromatase Inhibitors) as treatment for breast cancer commonly experience joint pain and stiffness (aromatase inhibitor associated arthralgia; AIAA) which can lead to early discontinuation of treatment. Exercise is often recommended and there is preliminary evidence it might prove helpful. Nordic Walking is a popular form of exercise in women with breast cancer, and based on a biopsychosocial model, could provide additional benefits over normal walking alone. Ther...

  2. Bilateral de quervain syndrome after aromatase inhibitor administration: a case report and review of the literature.

    Science.gov (United States)

    Papadimitriou, Konstantinos; Kountourakis, Panteleimon; Morakis, Emmanouil; Vassiliou, Vassilios; Barbounis, Vasileios; Ardavanis, Alexandros

    2012-01-01

    Aromatase inhibitors are widely used as one of the main treatment options of both early and advanced hormone receptor-positive breast cancer in postmenopausal women. Unfortunately, musculoskeletal symptoms are often presented in patients treated with aromatase inhibitors (AIs), and, although the pathogenesis is unknown, postulated mechanisms have been described. Herein, to our knowledge, we present the first report of bilateral De Quervain syndrome related with AIs therapy with a review of the relevant literature. PMID:22567020

  3. Bilateral De Quervain Syndrome after Aromatase Inhibitor Administration: A Case Report and Review of the Literature

    OpenAIRE

    Vasileios Barbounis; Vassilios Vassiliou; Emmanouil Morakis; Panteleimon Kountourakis; Konstantinos Papadimitriou; Alexandros Ardavanis

    2012-01-01

    Aromatase inhibitors are widely used as one of the main treatment options of both early and advanced hormone receptor-positive breast cancer in postmenopausal women. Unfortunately, musculoskeletal symptoms are often presented in patients treated with aromatase inhibitors (AIs), and, although the pathogenesis is unknown, postulated mechanisms have been described. Herein, to our knowledge, we present the first report of bilateral De Quervain syndrome related with AIs therapy with a review of th...

  4. Novel inhibitor discovery against aromatase through virtual screening and molecular dynamic simulation: a computational approach in drug design

    OpenAIRE

    Mirzaie, Sako; Chupani, Latifeh; Asadabadi, Ebrahim Barzegari; Shahverdi, Ahmad Reza; Jamalan, Mostafa

    2013-01-01

    Inhibition of aromatase (CYTP450) as a key enzyme in the estrogen biosynthesis could result in regression of estrogen-dependent tumors and even preventing the promotion of breast cancer. Although today potent steroid and non-steroid inhibitors of aromatase are available, isoflavanone derivatives as natural compounds with least side effects have been described as the candidate for a new generation of aromatase inhibitors. 2a as an isoflavanone derivative is the most potent inhibitor of aromata...

  5. Steroidal pyrazolines evaluated as aromatase and quinone reductase-2 inhibitors for chemoprevention of cancer.

    Science.gov (United States)

    Abdalla, Mohamed M; Al-Omar, Mohamed A; Bhat, Mashooq A; Amr, Abdel-Galil E; Al-Mohizea, Abdullah M

    2012-05-01

    The aromatase and quinone reductase-2 inhibition of synthesized heterocyclic pyrazole derivatives fused with steroidal structure for chemoprevention of cancer is reported herein. All compounds were interestingly less toxic than the reference drug (Cyproterone(®)). The aromatase inhibitory activities of these compounds were much more potent than the lead compound resveratrol, which has an IC(50) of 80 μM. In addition, all the compounds displayed potent quinone reductase-2 inhibition. Initially the acute toxicity of the compounds was assayed via the determination of their LD(50). The aromatase and quinone reductase-2 inhibitors resulting from this study have potential value in the treatment and prevention of cancer. PMID:22361454

  6. Synthesis and PET studies of [11C-cyano]letrozole (Femara), an aromatase inhibitor drug

    International Nuclear Information System (INIS)

    Introduction: Aromatase, a member of the cytochrome P450 family, converts androgens such as androstenedione and testosterone into estrone and estradiol, respectively. Letrozole (1-[bis-(4-cyanophenyl)methyl]-1H-1,2,4-triazole; Femara) is a high-affinity aromatase inhibitor (Ki=11.5 nM) that has Food and Drug Administration approval for breast cancer treatment. Here we report the synthesis of carbon-11-labeled letrozole and its assessment as a radiotracer for brain aromatase in the baboon. Methods: Letrozole and its precursor (4-[(4-bromophenyl)-1H-1,2,4-triazol-1-ylmethyl]benzonitrile) were prepared in a two-step synthesis from 4-cyanobenzyl bromide and 4-bromobenzyl bromide, respectively. The [11C]cyano group was introduced via tetrakis(triphenylphosphine)palladium(0)-catalyzed coupling of [11C]cyanide with the bromo precursor. Positron emission tomography (PET) studies in the baboon brain were carried out to assess regional distribution and kinetics, reproducibility of repeated measures and saturability. Log D, the free fraction of letrozole in plasma and the [11C-cyano]letrozole fraction in arterial plasma were also measured. Results: [11C-cyano]Letrozole was synthesized in 60 min with a radiochemical yield of 79-80%, with a radiochemical purity greater than 98% and a specific activity of 4.16±2.21 Ci/μmol at the end of bombardment (n=4). PET studies in the baboon revealed initial rapid and high uptake and initial rapid clearance, followed by slow clearance of carbon-11 from the brain, with no difference between brain regions. Brain kinetics was not affected by coinjection of unlabeled letrozole (0.1 mg/kg). The free fraction of letrozole in plasma was 48.9%, and log D was 1.84. Conclusion: [11C-cyano]Letrozole is readily synthesized via a palladium-catalyzed coupling reaction with [11C]cyanide. Although it is unsuitable as a PET radiotracer for brain aromatase, as revealed by the absence of regional specificity and saturability in brain regions such as

  7. Aromatase inhibitors - a viable option for recurrent granulosa cell tumour of ovary: overview and case report

    International Nuclear Information System (INIS)

    Granulosa cell tumour of the ovary in adults is a rare tumour of low malignant potential affecting middle aged peri or post menopausal patients. These tumours are often diagnosed at an early stage, due to their hormonally active nature. They, however, have unique distinguishing histologic features and behaviour of frequent and late local or systemic relapses. The diagnosis can be challenging with unusual presentations. There is high association of endometrial carcinoma. Surgery is the mainstay of management in early low risk disease, while radiotherapy and systemic platinum based chemotherapy are employed in higher stage with poor prognostic indices. Survival is good in early stage disease. Recurrent, progressive, and treatment refractory disease is not infrequent and poses management challenge. Endocrine manipulation and hormone treatment are employed in few cases with equivocal results, as reported in literature. We present a case of recurrent and treatment refractory GCT in a postmenopausal patient, managed by aromatase inhibitor Anastrozole with reasonable efficacy. (author)

  8. A Study to Evaluate Genetic Predictors of Aromatase Inhibitor Musculoskeletal Symptoms (AIMSS) | Division of Cancer Prevention

    Science.gov (United States)

    E1Z11 is a study to determine whether certain genetic information can predict which breast cancer patients will discontinue treatment with AIs due to the development of musculoskeletal symptoms (MSS). Women with stage 1-111 breast cancer who are prescribed the aromatase inhibitor anastrozole as treatment may join. |

  9. 3H- and 14C-labelling of the aromatase inhibitor ZK 138723

    International Nuclear Information System (INIS)

    It has been known for several years that the growth of certain neoplastic disorders - especially breast cancer in women -depends on the serum level of estrogen. One strategy of lowering the estrogen formation is to inhibit the action of the enzyme aromatase, which catalyzes the final step in estrogen biosynthesis in humans. For this purpose nonsteroidal compounds seem to offer advantages as compared to the classical steroid derivatives regarding intensity and duration of effect as well as selectivity to other cytochrome P450 enzymes. The competitive aromatase inhibitor ZK138723 is such a nonsteroidal compound. It was labelled with 3H and 14C to be used for further pharmacological investigations. (author)

  10. Adjuvant endocrine therapy for postmenopausal breast cancer in the era of aromatase inhibitors: an update

    OpenAIRE

    Mokbel, Ramia; Karat, Isabella; Mokbel, Kefah

    2006-01-01

    There is overwhelming evidence that optimal adjuvant endocrine therapy for hormone sensitive breast cancer in postmenopausal women should include a third generation aromatase inhibitor (AI). On current evidence, adjuvant anstrozole or letrozole should be used upfront in such patients especially in those with high risk disease (node positive and/or tumours > 2 cm). The sequential approach of tamoxifen for 2–3 years followed by exemestane or anastrozole for 2–3 years is a reasonable alternative...

  11. Design, synthesis, and biological evaluation of resveratrol analogues as aromatase and quinone reductase 2 inhibitors for chemoprevention of cancer

    International Nuclear Information System (INIS)

    A series of new resveratrol analogues were designed and synthesized and their inhibitory activities against aromatase were evaluated. The crystal structure of human aromatase (PDB 3eqm) was used to rationalize the mechanism of action of the aromatase inhibitor 32 (IC50 0.59 μM) through docking, molecular mechanics energy minimization, and computer graphics molecular modeling, and the information was utilized to design several very potent inhibitors, including compounds 82 (IC50 70 nM) and 84 (IC50 36 nM). The aromatase inhibitory activities of these compounds are much more potent than that for the lead compound resveratrol, which has an IC50 of 80 μM. In addition to aromatase inhibitory activity, compounds 32 and 44 also displayed potent QR2 inhibitory activity (IC50 1.7 μM and 0.27 μM, respectively) and the high-resolution X-ray structures of QR2 in complex with these two compounds provide insight into their mechanism of QR2 inhibition. The aromatase and quinone reductase inhibitors resulting from these studies have potential value in the treatment and prevention of cancer.

  12. Managing arthralgia in a postmenopausal woman taking an aromatase inhibitor for hormonesensitive early breast cancer: a case study

    International Nuclear Information System (INIS)

    In order to reduce the risk of recurrence, adjuvant treatment with an aromatase inhibitor (AI) is recommended for postmenopausal women following surgery for hormone receptor-positive breast cancer. AIs are associated with improved disease-free survival compared with tamoxifen. The adverse events associated with AIs resemble those of menopause, such as bone density loss and musculoskeletal symptoms. We examine the case of a postmenopausal woman who was prescribed anastrozole, a nonsteroidal AI, as adjuvant therapy following surgery for estrogen and progesterone receptor-positive (ER and PgR+) breast cancer. A 58-year-old postmenopausal woman diagnosed with ER and PgR+ breast cancer was prescribed anastrozole as adjuvant therapy following a right-inferior quadrantectomy. After experiencing joint pain and stiffness, she was prescribed paracetamol and a topical nonsteroidal anti-inflammatory drug. She was also counseled on nonpharmacological interventions. However, she continued to experience symptoms, and reported that she was not taking anastrozole regularly. The case study patient ultimately found relief by switching to letrozole, another aromatase inhibitor. This approach is supported by recent studies examining the benefits of switching strategies between aromatase inhibitors in order to relieve symptoms of arthralgia/myalgia. Both adherence and strategies for managing aromatase inhibitor-associated arthralgia are key to deriving maximal clinical benefit from AI therapy. Switching from one aromatase inhibitor to another may provide a viable option in managing adverse events and enhancing adherence to medication

  13. Synthesis of Triphenylethylene Bisphenols as Aromatase Inhibitors That Also Modulate Estrogen Receptors.

    Science.gov (United States)

    Lv, Wei; Liu, Jinzhong; Skaar, Todd C; O'Neill, Elizaveta; Yu, Ge; Flockhart, David A; Cushman, Mark

    2016-01-14

    A series of triphenylethylene bisphenol analogues of the selective estrogen receptor modulator (SERM) tamoxifen were synthesized and evaluated for their abilities to inhibit aromatase, bind to estrogen receptor α (ER-α) and estrogen receptor β (ER-β), and antagonize the activity of β-estradiol in MCF-7 human breast cancer cells. The long-range goal has been to create dual aromatase inhibitor (AI)/selective estrogen receptor modulators (SERMs). The hypothesis is that in normal tissue the estrogenic SERM activity of a dual AI/SERM could attenuate the undesired effects stemming from global estrogen depletion caused by the AI activity of a dual AI/SERM, while in breast cancer tissue the antiestrogenic SERM activity of a dual AI/SERM could act synergistically with AI activity to enhance the antiproliferative effect. The potent aromatase inhibitory activities and high ER-α and ER-β binding affinities of several of the resulting analogues, together with the facts that they antagonize β-estradiol in a functional assay in MCF-7 human breast cancer cells and they have no E/Z isomers, support their further development in order to obtain dual AI/SERM agents for breast cancer treatment. PMID:26704594

  14. Everolimus downregulates estrogen receptor and induces autophagy in aromatase inhibitor-resistant breast cancer cells

    OpenAIRE

    Lui, Asona; New, Jacob; Ogony, Joshua; Thomas, Sufi; Lewis-Wambi, Joan

    2016-01-01

    Background mTOR inhibition of aromatase inhibitor (AI)-resistant breast cancer is currently under evaluation in the clinic. Everolimus/RAD001 (Afinitor®) has had limited efficacy as a solo agent but is projected to become part of combination therapy for AI-resistant breast cancer. This study was conducted to investigate the anti-proliferative and resistance mechanisms of everolimus in AI-resistant breast cancer cells. Methods In this study we utilized two AI-resistant breast cancer cell lines...

  15. Managing arthralgia in a postmenopausal woman taking an aromatase inhibitor for hormone-sensitive early breast cancer: a case study

    Directory of Open Access Journals (Sweden)

    Bryce J

    2012-03-01

    Full Text Available Jane Bryce1, Martina Bauer2, Peyman Hadji21National Cancer Institute, Naples, Italy; 2Philipps University of Marburg, Marburg, GermanyBackground: In order to reduce the risk of recurrence, adjuvant treatment with an aromatase inhibitor (AI is recommended for postmenopausal women following surgery for hormone receptor-positive breast cancer. AIs are associated with improved disease-free survival compared with tamoxifen. The adverse events associated with AIs resemble those of menopause, such as bone density loss and musculoskeletal symptoms.Purpose: We examine the case of a postmenopausal woman who was prescribed anastrozole, a nonsteroidal AI, as adjuvant therapy following surgery for estrogen and progesterone receptor-positive (ER and PgR+ breast cancer.Methods and sample: A 58-year-old postmenopausal woman diagnosed with ER and PgR+ breast cancer was prescribed anastrozole as adjuvant therapy following a right-inferior quadrantectomy. After experiencing joint pain and stiffness, she was prescribed paracetamol and a topical nonsteroidal anti-inflammatory drug. She was also counseled on nonpharmacological interventions. However, she continued to experience symptoms, and reported that she was not taking anastrozole regularly.Results: The case study patient ultimately found relief by switching to letrozole, another aromatase inhibitor. This approach is supported by recent studies examining the benefits of switching strategies between aromatase inhibitors in order to relieve symptoms of arthralgia/myalgia.Conclusions: Both adherence and strategies for managing aromatase inhibitor-associated arthralgia are key to deriving maximal clinical benefit from AI therapy. Switching from one aromatase inhibitor to another may provide a viable option in managing adverse events and enhancing adherence to medication.Keywords: adherence, anastrozole, aromatase inhibitor, arthralgia, breast cancer, letrozole

  16. Patient adherence to aromatase inhibitor treatment in the adjuvant setting

    OpenAIRE

    Verma, S.; Madarnas, Y.; Sehdev, S.; Martin, G; Bajcar, J.

    2011-01-01

    Improvements in adjuvant systemic therapy and detection of early disease have resulted in a decline of breast cancer death rates across all patient age groups in Canada. Non-adherence to adjuvant hormonal therapy in the setting of early breast cancer may significantly affect patient outcome. Factors associated with medication adherence are complex and may be patient-related, therapy-related, and health care provider–related. To date, there is a gap in the literature concerning a comprehensive...

  17. Long-term safety of aromatase inhibitors in the treatment of breast cancer

    Directory of Open Access Journals (Sweden)

    Jean-Marc A Nabholtz

    2008-03-01

    Full Text Available Jean-Marc A NabholtzBreast Cancer Research Institute La Prandie, Valojoulx, FranceAbstract: Following promising data for metastatic breast cancer in terms of efficacy and safety profile, third-generation aromatase inhibitors (AI, anastrozole, letrozole, and exemestane, underwent a full development in early setting. If recent results consistently show the superiority of these agents over tamoxifen, the therapeutic strategies of AIs in adjuvant setting are still debated. Beyond the choice of clinical strategy, the long duration of exposure to AI in adjuvant setting required a full determination of the long-term toxicity profile of these agents. While all three AIs have either favorable (decreased incidence of hot flashes, gynecologic and thromboembolic side-effects or unfavorable (skeletal complications, arthralgia, musculoskeletal pain, sexual dysfunction class adverse events, some variability between AIs has been reported in side-effects as well as gastrointestinal, urogenital, neurologic, and visual disturbances, confirming the lack of interchangeability between the three AIs. The overall therapeutic index of AIs appears today superior to that of tamoxifen with proven improved efficacy and better toxicity profile. This review will explore the results from the available adjuvant AIs trials with a particular emphasis on safety profiles, quality of life, and therapeutic index, helping to define the present role of AIs in the adjuvant management of postmenopausal patients with breast cancer.Keywords: breast cancer, aromatase inhibitors, adjuvant, safety profile

  18. Management of adenomyosis in infertile women: comparison between laparotomic resection and administration of aromatase inhibitor (Experience in 55 cases

    Directory of Open Access Journals (Sweden)

    Rajuddin Rajuddin

    2006-03-01

    Full Text Available The objective of this study was to observe the results of adenomyosis mangement with resection and administration of aromatase inhibitor. Cases of ademyosis in infertile women were collected for three years (January 1999 to December 2001 and the diagnoses were confirmed using transvaginal USG. Cases were grouped into two groups, i.e. group 1 (undergoing laparotomic resection and group 2 (receiving treatment with aromatase inhibitor of anastrozole. Both groups were evaluated for changes in clinical symptoms, rate of successful pregnancy, and postoperative recurrency rate. During three years as many as 1619 infertility cases were managed, and among which 66 (4.07% cases of adenomyosis were diagnosed with transvaginal USG. As many as 55 cases were analyzed, i.e., 32 cases underwent resection and 23 cases received aromatase inhibitor. Of 32 cases of surgical resection, the histopathological results showed 30 (93.75% cases of adenomyosis and 2 (6.25% cases of uterus myoma. In the group undergoing resection three cases (9.4% were successfully pregnant, i.e., two cases had live birth, one case ended up with 6-week abortion. Moreover, 25 (78.1% cases were not pregnant and 4 (12.5% cases had recurrency, while 24 (75.35% cases experienced disappearance of symptoms yet not pregnant. On the other hand, of 23 cases in the group receiving aromatase inhibitor 2 (8.6% cases were able to be pregnant, one case had live birth and another case ended up with abortion, while 14 (59.1% cases had disappearance of symptoms yet not pregnant. During three months of treatment with aromatase inhibitor, a reduction in the lesion size between 7.31 mm3 and 25.90 mm3 were observed with CI 95% (p < 0.001. In conclusion, treatment with aromatase inihibitor did not heal lesions, but only reduced the size of adenomyosis lesions. On the other hand, resection could heal lesions, yet recurrency of disease may occur (12.5% after one postoperative year. (Med J Indones 2006; 15

  19. Induction of Female-to-Male Sex Change in Adult Zebrafish by Aromatase Inhibitor Treatment

    Science.gov (United States)

    Takatsu, Kanae; Miyaoku, Kaori; Roy, Shimi Rani; Murono, Yuki; Sago, Tomohiro; Itagaki, Hideyuki; Nakamura, Masaru; Tokumoto, Toshinobu

    2013-12-01

    This study investigated whether undifferentiated germ and/or somatic stem cells remain in the differentiated ovary of a species that does not undergo sex changes under natural conditions and retain their sexual plasticity. The effect of aromatase inhibitor (AI)-treatment on sexually mature female zebrafish was examined. A 5-month AI treatment caused retraction of the ovaries after which testes-like organs appeared, and cyst structures filled with spermatozoa-like cells were observed in sections of these tissues. Electron microscopic observations revealed that these cells appeared as large sperm heads without tails. Sperm formation was re-examined after changing the diet to an AI-free food. A large number of normal sperm were obtained after eight weeks, and no formation of ovarian tissue was observed. Artificial fertilization using sperm from the sex-changed females was successful. These results demonstrated that sex plasticity remains in the mature ovaries of this species.

  20. Aromatase inhibitors, efficacy and metabolic risk in the treatment of postmenopausal women with early breast cancer

    Directory of Open Access Journals (Sweden)

    Stefano Gonnelli

    2008-11-01

    Full Text Available Stefano Gonnelli1, Roberto Petrioli21Department of Internal Medicine, Endocrine-Metabolic Science and Biochemistry, University of Siena, Italy (Dir. R. Nuti.; 2Department of Human Pathology and Oncology, Medical Oncology Section, University of Siena, Italy (Dir. G. FranciniAbstract: The third-generation aromatase inhibitors (AIs, letrozole, anastrozole and exemestane, are becoming the first choice endocrine drugs for post-menopausal women with breast cancer, since they present greater efficacy when compared with tamoxifen in both adjuvant and metastatic setting. In particular, several large and well designed trials have suggested an important role for AIs in the adjuvant treatment of postmenopausal women with estrogen-receptor positive breast cancer either in the upfront, sequential or extended adjuvant mode. Overall, AIs are associated with a small but significant improvement in disease free survival. The expanding use of AIs in the treatment of early breast cancer means that individual patients will be exposed to the agents for longer durations, making it increasingly important to establish their long-term safety. This review focused on the effects of AIs on bone metabolism, serum lipids and cardiovascular risk. AIs have adverse effects on bone turnover with a reduction of bone mineral density and an increase in the rate of fragility fractures. With respect to tamoxifen AIs present lower thrombotic risk and a less favorable impact on lipid profile, whereas the true effects on cardiovascular risk still remain to be clarified. An adequate monitoring of bone mineral density (BMD and lipid profile could be recommended for post-menopausal women candidate to AIs.Keywords: breast cancer, aromatase inhibitors, bone loss, lipids, cardiovascular risk

  1. Recent Progress in the Discovery of Next Generation Inhibitors of Aromatase from the Structure-Function Perspective.

    Science.gov (United States)

    Ghosh, Debashis; Lo, Jessica; Egbuta, Chinaza

    2016-06-01

    Human aromatase catalyzes the synthesis of estrogen from androgen with high substrate specificity. For the past 40 years, aromatase has been a target of intense inhibitor discovery research for the prevention and treatment of estrogen-dependent breast cancer. The so-called third generation aromatase inhibitors (AIs) letrozole, anastrozole, and the steroidal exemestane were approved in the U.S. in the late 1990s for estrogen-dependent postmenopausal breast cancer. Efforts to develop better AIs with higher selectivity and lower side effects were handicapped by the lack of an experimental structure of this unique P450. The year 2009 marked the publication of the crystal structure of aromatase purified from human placenta, revealing an androgen-specific active site. The structure has reinvigorated research activities on this fascinating enzyme and served as the catalyst for next generation AI discovery research. Here, we present an account of recent developments in the AI field from the perspective of the enzyme's structure-function relationships. PMID:26689671

  2. Molecular characterization of aromatase

    OpenAIRE

    Hong, Yanyan; Li, Hongzhi; Yuan, Yate-Ching; Chen, Shiuan

    2009-01-01

    Aromatase is an estrogen synthetase. Estrogens are female sex hormones involved in the development and growth of breast tumors. It has been of significant interest to elucidate the structure-function relationship of aromatase since its inhibitors have shown great promise in fighting breast cancer. Aromatase belongs to the cytochrome P450 family, and forms an electron-transfer complex with its partner, NADPH-cytochrome P450 reductase. Because of the membrane-bound character and heme-binding in...

  3. New steroidal aromatase inhibitors: Suppression of estrogen-dependent breast cancer cell proliferation and induction of cell death

    Directory of Open Access Journals (Sweden)

    Roleira Fernanda MF

    2008-07-01

    Full Text Available Abstract Background Aromatase, the cytochrome P-450 enzyme (CYP19 responsible for estrogen biosynthesis, is an important target for the treatment of estrogen-dependent breast cancer. In fact, the use of synthetic aromatase inhibitors (AI, which induce suppression of estrogen synthesis, has shown to be an effective alternative to the classical tamoxifen for the treatment of postmenopausal patients with ER-positive breast cancer. New AIs obtained, in our laboratory, by modification of the A and D-rings of the natural substrate of aromatase, compounds 3a and 4a, showed previously to efficiently suppress aromatase activity in placental microsomes. In the present study we have investigated the effects of these compounds on cell proliferation, cell cycle progression and induction of cell death using the estrogen-dependent human breast cancer cell line stably transfected with the aromatase gene, MCF-7 aro cells. Results The new steroids inhibit hormone-dependent proliferation of MCF-7aro cells in a time and dose-dependent manner, causing cell cycle arrest in G0/G1 phase and inducing cell death with features of apoptosis and autophagic cell death. Conclusion Our in vitro studies showed that the two steroidal AIs, 3a and 4a, are potent inhibitors of breast cancer cell proliferation. Moreover, it was also shown that the antiproliferative effects of these two steroids on MCF-7aro cells are mediated by disrupting cell cycle progression, through cell cycle arrest in G0/G1 phase and induction of cell death, being the dominant mechanism autophagic cell death. Our results are important for the elucidation of the cellular effects of steroidal AIs on breast cancer.

  4. Advances in breast cancer treatment and prevention: preclinical studies on aromatase inhibitors and new selective estrogen receptor modulators (SERMs)

    OpenAIRE

    Schiff, Rachel; Chamness, Gary C.; Brown, Powel H.

    2003-01-01

    Intensive basic and clinical research over the past 20 years has yielded crucial molecular understanding into how estrogen and the estrogen receptor act to regulate breast cancer and has led to the development of more effective, less toxic, and safer hormonal therapy agents for breast cancer management and prevention. Selective potent aromatase inhibitors are now challenging the hitherto gold standard of hormonal therapy, the selective estrogen-receptor modulator tamoxifen. Furthermore, new s...

  5. Intratumoral concentration of estrogens and clinicopathological changes in ductal carcinoma in situ following aromatase inhibitor letrozole treatment

    OpenAIRE

    Takagi, K.; Ishida, T; Miki, Y; Hirakawa, H; Kakugawa, Y; Amano, G.; Ebata, A.; Mori, N; Nakamura, Y.; Watanabe, M.; Amari, M; Ohuchi, N.; Sasano, H; Suzuki, T

    2013-01-01

    Background: Estrogens have important roles in ductal carcinoma in situ (DCIS) of the breast. However, the significance of presurgical aromatase inhibitor treatment remains unclear. Therefore, we examined intratumoral concentration of estrogens and changes of clinicopathological factors in DCIS after letrozole treatment. Methods: Ten cases of postmenopausal oestrogen receptor (ER)-positive DCIS were examined. They received oral letrozole before the surgery, and the tumour size was evaluated by...

  6. Use of aromatase inhibitors to treat endometriosis-related pain symptoms: a systematic review

    Directory of Open Access Journals (Sweden)

    Venturini Pier L

    2011-06-01

    Full Text Available Abstract This systematic review aims to assess the efficacy of aromatase inhibitors (AIs in treating pain symptoms caused by endometriosis. A comprehensive literature search was conducted to identify all the published studies evaluating the efficacy of type II nonsteroidal aromatase inhibitors (anastrozole and letrozole in treating endometriosis-related pain symptoms. The MEDLINE, EMBASE, PubMed, and SCOPUS databases and the Cochrane System Reviews were searched up to October 2010. This review comprises of the results of 10 publications fitting the inclusion criteria; these studies included a total of 251 women. Five studies were prospective non-comparative, four were randomized controlled trials (RCTs and one was a prospective patient preference trial. Seven studies examined the efficacy of AIs in improving endometriosis-related pain symptoms, whilst three RCTs investigated the use of AIs as post-operative therapy in preventing the recurrence of pain symptoms after surgery for endometriosis. All the observational studies demonstrated that AIs combined with either progestogens or oral contraceptive pill reduce the severity of pain symptoms and improve quality of life. One patient preference study demonstrated that letrozole combined with norethisterone acetate is more effective in reducing pain and deep dyspareunia than norethisterone acetate alone. However, letrozole causes a higher incidence of adverse effects and does not improve patients' satisfaction or influence recurrence of symptoms after discontinuation of treatment. A RCT showed that combining letrozole with norethisterone acetate causes a lower incidence of adverse effects and lower discontinuation rate than combining letrozole with triptorelin. Two RCTs demonstrated that, after surgical treatment of endometriosis, the administration of AIs combined with gonadotropin releasing hormone analogue for 6 months reduces the risk of endometriosis recurrence when compared with gonadotropin

  7. Postmenopausal Breast Cancer, Aromatase Inhibitors, and Bone Health: What the Surgeon Should Know.

    Science.gov (United States)

    Baatjes, K J; Apffelstaedt, J P; Kotze, M J; Conradie, M

    2016-09-01

    Breast cancer, as the most common malignancy in women, remains a major public health issue despite countless advances across decades. Endocrine therapy is the cornerstone of treatment of the hormone-sensitive subtype of breast cancer. The use of aromatase inhibitors (AIs) in the postmenopausal women has extended the survival beyond that of Tamoxifen, but harbors a subset of side effects, most notably accelerated bone loss. This, however, does not occur in all women undergoing treatment. It is vital to identify susceptible patients early, to limit such events, employ early treatment thereof, or alter drug therapy. International trials on AIs, predominantly performed in North American and European females, provide little information on what to expect in women in developing countries. Here, surgeons often prescribe and manage endocrine therapy. The prescribing surgeon should be aware of the adverse effect of the endocrine therapy and be able to attend to side effects. This review highlights clinical and biochemical factors associated with decrease in bone mineral density in an, as yet, unidentified subgroup of postmenopausal women. In the era of personalized medical care, appropriate management of bone health by surgeons based on these factors becomes increasingly important. PMID:27189076

  8. A Case of Erythrocytosis in a Patient Treated with an Aromatase Inhibitor for Breast Cancer

    Directory of Open Access Journals (Sweden)

    Abhinav Iyengar

    2013-01-01

    Full Text Available A previously healthy 79-year-old female was referred to hematology for further evaluation of erythrocytosis. Two years earlier she had been diagnosed with ER/PR-positive ductal carcinoma of the breast and was receiving hormonal therapy with exemestane. No secondary cause of erythrocytosis was identified. Serum erythropoietin (EPO level was normal, and molecular testing for the JAK2 V617F and exon 12 mutations was negative. A bone marrow biopsy showed a mild increase in erythropoiesis, and no spontaneous erythroid colonies were demonstrated. Erythrocytosis is common reason for referral to a hematologist. The myeloproliferative disorder, polycythemia vera, and the rare congenital polycythemias represent primary erythrocytosis. Common secondary causes include smoking, obstructive sleep apnea, and other pulmonary diseases. Erythrocytosis is well described with certain classes of drugs, including androgens. We hypothesize that exemestane contributed to the development of erythrocytosis in our patient. To our knowledge, erythrocytosis has not been previously described in association with aromatase inhibitors. These drugs prevent the conversion of androstenedione and testosterone to estrogen; thus the physiologic mechanisms may be similar to those responsible for erythrocytosis seen with exogenous androgens. These mechanisms are not well understood, but may include altered iron metabolism by a reduction in hepcidin levels.

  9. Adjuvant endocrine therapy for postmenopausal breast cancer in the era of aromatase inhibitors: an update.

    Science.gov (United States)

    Mokbel, Ramia; Karat, Isabella; Mokbel, Kefah

    2006-01-01

    There is overwhelming evidence that optimal adjuvant endocrine therapy for hormone sensitive breast cancer in postmenopausal women should include a third generation aromatase inhibitor (AI). On current evidence, adjuvant anstrozole or letrozole should be used upfront in such patients especially in those with high risk disease (node positive and/or tumours > 2 cm). The sequential approach of tamoxifen for 2-3 years followed by exemestane or anastrozole for 2-3 years is a reasonable alternative to 5 years of AI monotherapy in patients with low risk disease (node negative and tumour smaller than 2 cm) especially if the tumour is positive for estrogen and progesterone receptors.Node-positive patients completing 5 years of adjuvant tamoxifen should be offered letrozole for up 48 months. Further research is required to establish the long-term cardiovascular safety of AIs especially that of letrozole and exmestane, the optimal AI to use, duration of AI therapy and whether monotherapy with an AI for 5 years is superior to sequencing an AI after 2-3 years of tamoxifen. The bone mineral density (BMD) should be measured at baseline and monitored during therapy in women being treated with AIs. Anti-osteoporosis agents should such as bisphosphonates should be considered in patients at high risk of bone fractures. PMID:16981992

  10. Metastatic progression with resistance to aromatase inhibitors is driven by the steroid receptor coactivator SRC-1.

    Science.gov (United States)

    McBryan, Jean; Theissen, Sarah M; Byrne, Christopher; Hughes, Eamon; Cocchiglia, Sinead; Sande, Stephen; O'Hara, Jane; Tibbitts, Paul; Hill, Arnold D K; Young, Leonie S

    2012-01-15

    Aromatase inhibitors (AI) are a standard-of-care treatment for postmenopausal, estrogen receptor-positive breast cancers. Although tumor recurrence on AI therapy occurs, the mechanisms underlying acquired resistance to AIs remain unknown. In this study, we examined a cohort of endocrine-treated breast cancer patients and used a cell line model of resistance to the AI letrozole. In patients treated with a first-line AI, hormone receptor switching between primary and resistant tumors was a common feature of disease recurrence. Resistant cells exhibited a switch from steroid-responsive growth to growth factor-responsive and endocrine-independent growth, which was accompanied by the development of a more migratory and disorganized phenotype. Both the resistant cells and tumors from AI-resistant patients showed high expression of the steroid receptor coactivator SRC-1. Direct interactions between SRC-1 and the transcription factor Ets2 regulated Myc and MMP9. SRC-1 was required for the aggressive and motile phenotype of AI-resistant cells. Interestingly, SRC-1 expression in primary and/or recurrent tumors was associated with a reduction in disease-free survival in treated patients. Moreover, there was a significant association between SRC-1 and Ets2 in the recurrent tissue compared with the matched primary tumor. Together, our findings elucidate a mechanism of AI-specific metastatic progression in which interactions between SRC-1 and Ets2 promote dedifferentiation and migration in hormone-dependent breast cancer. PMID:22108824

  11. Vaginal estrogen products in hormone receptor-positive breast cancer patients on aromatase inhibitor therapy.

    Science.gov (United States)

    Sulaica, Elisabeth; Han, Tiffany; Wang, Weiqun; Bhat, Raksha; Trivedi, Meghana V; Niravath, Polly

    2016-06-01

    Atrophic vaginitis represents a major barrier to compliance with aromatase inhibitor (AI) therapy in breast cancer (BC) survivors. While local estrogen therapy is effective for postmenopausal vaginal dryness, the efficacy of such therapies has not been evaluated systematically in hormone receptor-positive (HR+) BC patients on AI therapy. Furthermore, the potential risk of breast cancer recurrence with vaginal estrogen therapy represents a long-term safety concern for the patients with HR + BC. Unfortunately, there is no standardized assay to measure very low concentrations of estradiol (E2) in these women being treated with AI therapy. This makes it difficult to evaluate even indirectly the potential risk of BC recurrence with vaginal estrogen therapy in HR + BC patients on AI therapy. In this review, we describe available assays to measure very low concentrations of E2, discuss the Food and Drug Administration-approved vaginal estrogen products on the market, and summarize published and ongoing clinical trials evaluating the safety and efficacy of vaginal estrogen in HR + BC patients on AI therapy. In the absence of any randomized controlled clinical trials, this review serves as a summary of available clinical data and ongoing studies to aid clinicians in selecting the best available option for their patients. PMID:27178335

  12. Aromatase inhibitors in breast cancer: the discovery of new computational design and biochemical evaluation

    OpenAIRE

    Neves, Marco André Coelho das

    2009-01-01

    Continuous exposure to high levels of endogenous estrogens is associated with increased risks of developing breast cancer. In this sense, aromatase, the cytochrome P450 enzyme involved in the conversion of androgens, testosterone and androstenedione, into estrogens, estradiol and estrone, is an important target for the endocrine treatment of breast cancer in postmenopausal women. Aromatase inhibition is achieved either with compounds structurally related to the androstenedio...

  13. Evaluation of the quality and accuracy of information regarding aromatase inhibitors available on the internet.

    Science.gov (United States)

    Beaton, Ceri; Codd, Rhodri J; Holland, Phillip A; Gateley, Christopher A

    2008-01-01

    The internet is commonly used by patients to access medical information, particularly where new treatments become available and are highlighted in the press. There is however, no regulation of the quality or accuracy of the information presented on web sites. The aim of this study was to evaluate the quality and accuracy of the information concerning the aromatase inhibitors (AIs). The three most popular search engines: Google, Yahoo, and MSN were utilized. The top ten "hits" for the generic and proprietary names of each AIs: anastrozole (Arimidex), exemestane (Aromasin), and letrozole (Femara) were evaluated using a 12-point score by a single assessor. The accuracy of the information provided was compared with the National Institute for Health and Clinical Excellence guidelines. The mean score for the 180 web sites was only 6.13 out of 12 (0-11). If we consider a score of 9 or more out of 12 (> or =75%) for a web site to represent good quality information, then 51 (28%) of pages scored well. Google was slightly better than Yahoo and MSN; with the highest percentage of web sites scoring well. In evaluating hits according to type of web sites, 50 (28%) were charity web sites and 30 (17%) were drug company web sites and both groups scored significantly higher than the overall mean (charity p = 0.014, drug company p = 0.001). Only 2 of 180 hits gave accurate statistical evidence regarding the benefits of AIs over tamoxifen. We have found that the quality and accuracy of information concerning AIs provided on the Internet is poor and patients using it are unlikely to find accurate information. It is therefore our duty as healthcare providers to guide patients, so as to avoid them from being overwhelmed by irrelevant and conflicting information. PMID:18537915

  14. Aromatase inhibitors augment nociceptive behaviors in rats and enhance the excitability of sensory neurons.

    Science.gov (United States)

    Robarge, Jason D; Duarte, Djane B; Shariati, Behzad; Wang, Ruizhong; Flockhart, David A; Vasko, Michael R

    2016-07-01

    Although aromatase inhibitors (AIs) are commonly used therapies for breast cancer, their use is limited because they produce arthralgia in a large number of patients. To determine whether AIs produce hypersensitivity in animal models of pain, we examined the effects of the AI, letrozole, on mechanical, thermal, and chemical sensitivity in rats. In ovariectomized (OVX) rats, administering a single dose of 1 or 5mg/kg letrozole significantly reduced mechanical paw withdrawal thresholds, without altering thermal sensitivity. Repeated injection of 5mg/kg letrozole in male rats produced mechanical, but not thermal, hypersensitivity that extinguished when drug dosing was stopped. A single dose of 5mg/kg letrozole or daily dosing of letrozole or exemestane in male rats also augmented flinching behavior induced by intraplantar injection of 1000nmol of adenosine 5'-triphosphate (ATP). To determine whether sensitization of sensory neurons contributed to AI-induced hypersensitivity, we evaluated the excitability of neurons isolated from dorsal root ganglia of male rats chronically treated with letrozole. Both small and medium-diameter sensory neurons isolated from letrozole-treated rats were more excitable, as reflected by increased action potential firing in response to a ramp of depolarizing current, a lower resting membrane potential, and a lower rheobase. However, systemic letrozole treatment did not augment the stimulus-evoked release of the neuropeptide calcitonin gene-related peptide (CGRP) from spinal cord slices, suggesting that the enhanced nociceptive responses were not secondary to an increase in peptide release from sensory endings in the spinal cord. These results provide the first evidence that AIs modulate the excitability of sensory neurons, which may be a primary mechanism for the effect of these drugs to augment pain behaviors in rats. PMID:27072527

  15. Uso de inibidores da aromatase no tratamento do câncer de mama e osteoporose = The use of aromatase inhibitors for breast cancer treatment and osteoporosis

    Directory of Open Access Journals (Sweden)

    Cassol, Lina Barbosa

    2005-01-01

    Conclusão: Estratégias diagnósticas, preventivas e, eventualmente, terapêuticas de osteoporose devem ser empregadas precocemente em pacientes com câncer de mama tratadas com inibidores da aromatase

  16. Effects of the aromatase inhibitor Letrozole on serum immunoglobulin and lysozyme levels in immunized rainbow trout (Oncorhynchus mykiss Walbaum females

    Directory of Open Access Journals (Sweden)

    Paria Akbary

    2013-12-01

    Full Text Available Letrozole is a synthetic aromatase inhibitor and interfere in the committed step in the synthesis of endogenous estrogens from androgens. Also estrogens regulate the immune system in teleost. Changes of 17- β- esrtradiol (E2, serum immunoglobulin and lysozyme levels were measured using a method based on the ability of lysozyme to lyse the bacterium Micrococcus lysodeikticus, enzyme-linked immunosorbent assay (ELISA and ELISA respectively. Twelve broodstocks were injected weekly with 2.5 mg kg-1 letrozole (an endocrine disrupter component two months before spawning season and vaccinated intraperitoneally (i.p with a bacterin (inactivated L. garviae one month before spawning. Twelve broodstocks for vaccination and twelve female rainbow trout as control group were also immiunised (i.p with the bacterin and injected (i.p with PBS, respectively. In the group received 2.5 mg AI kg-1 per week, serum E2 levels were significantly lower than that of other groups. Total immunoglobulin level and lysozyme activity were significantly higher in the parents received 2.5 mg kg-1 per week and were immunized with 10-9 cells ml-1 Lactococcus garvieae  compared to the group which immunized with L. garvieae and the control (non- immunized. The present study, suggests that aromatase inhibitors such as letrozole may be a potential tool to regulate the synthesis of E2, is involved in the hormone- immune system interaction in rainbow trout.

  17. Acute Stress Differentially Affects Aromatase Activity in Specific Brain Nuclei of Adult Male and Female Quail

    OpenAIRE

    Dickens, Molly J; Cornil, Charlotte; Balthazart, Jacques

    2011-01-01

    The rapid and temporary suppression of reproductive behavior is often assumed to be an important feature of the adaptive acute stress response. However, how this suppression operates at the mechanistic level is poorly understood. The enzyme aromatase converts testosterone to estradiol in the brain to activate reproductive behavior in male Japanese quail (Coturnix japonica). The discovery of rapid and reversible modification of aromatase activity (AA) provides a potential mechanism for fast, s...

  18. Androgen priming using aromatase inhibitor and hCG during early-follicular-phase GnRH antagonist down-regulation in modified antagonist protocols

    DEFF Research Database (Denmark)

    Løssl, Kristine; Andersen, A N; Loft, A; Freiesleben, N L C; Bangsbøll, S; Andersen, C Yding

    2006-01-01

    Temporary exposure of follicles to increased levels of androgens may enhance their sensitivity to FSH. The aim of this study was to increase the intraovarian androgen level using aromatase inhibitors and hCG before controlled ovarian stimulation (COH) and to test this concept clinically....

  19. Short-term androgen priming by use of aromatase inhibitor and hCG before controlled ovarian stimulation for IVF. A randomized controlled trial

    DEFF Research Database (Denmark)

    Lossl, K; Andersen, C Yding; Loft, A; Freiesleben, N L C; Bangsbøll, S; Andersen, A Nyboe; Løssl, Kristine

    2008-01-01

    Temporary exposure of follicles to increased levels of androgens may augment follicular responsiveness. The present study tested whether short-term androgen priming by aromatase inhibitor and human chorionic gonadotrophin (hCG) before controlled ovarian stimulation (COS) increases the number of top...

  20. Advances in breast cancer treatment and prevention: preclinical studies on aromatase inhibitors and new selective estrogen receptor modulators (SERMs)

    International Nuclear Information System (INIS)

    Intensive basic and clinical research over the past 20 years has yielded crucial molecular understanding into how estrogen and the estrogen receptor act to regulate breast cancer and has led to the development of more effective, less toxic, and safer hormonal therapy agents for breast cancer management and prevention. Selective potent aromatase inhibitors are now challenging the hitherto gold standard of hormonal therapy, the selective estrogen-receptor modulator tamoxifen. Furthermore, new selective estrogen-receptor modulators such as arzoxifene, currently under clinical development, offer the possibility of selecting one with a more ideal pharmacological profile for treatment and prevention of breast cancer. Two recent studies in preclinical model systems that evaluate mechanisms of action of these new drugs and suggestions about their optimal clinical use are discussed

  1. [Indoleamine 2,3-Dioxygenase Activity during Fulvestrant Therapy for Aromatase Inhibitor-Resistant Metastatic Breast Cancer].

    Science.gov (United States)

    Sakurai, Kenichi; Fujisaki, Shigeru; Suzuki, Shuhei; Adachi, Keita; Nagashima, Saki; Masuo, Yuki; Tomita, Ryouichi; Gonda, Kenji; Enomoto, Katsuhisa; Amano, Sadao; Matsuo, Sadanori; Umeda, Nao

    2015-10-01

    We evaluated the clinical significance of indoleamine 2,3-dioxygenase (IDO) during fulvestrant therapy for aromatase inhibitor (AI)-resistant metastatic breast cancer. IDO activity can be measured by the tryptophan (Trp)/kynurenine (Kyn) ratio. Trp and Kyn were measured with high performance liquid chromatography (HPLC). Patients with AI resistant metastatic breast cancer had a 28.6% response rate to fulvestrant therapy, and the clinical benefit rate was 76.2%. AI-resistant metastatic breast cancer patients with distant metastases had a lower serum Trp/Kyn level than patients who had local recurrences. During fulvestrant therapy, IDO activity significantly decreased in the fulvestrant responder group compared to that in the fulvestrant non-responder group. During fulvestrant therapy, the IDO activity correlated with the number of metastatic lesions. These results suggest that measuring the Trp/Kyn ratio is useful for evaluating immunological metastatic status during endocrine therapy. PMID:26489554

  2. Relationship Between Breast Density and Selective Estrogen-Receptor Modulators, Aromatase Inhibitors, Physical Activity, and Diet: A Systematic Review.

    Science.gov (United States)

    Ekpo, Ernest U; Brennan, Patrick C; Mello-Thoms, Claudia; McEntee, Mark F

    2016-06-01

    Background Lower breast density (BD) is associated with lower risk of breast cancer and may serve as a biomarker for the efficacy of chemopreventive strategies. This review explores parameters that are thought to be associated with lower BD. We conducted a systematic review of articles published to date using the PRISMA strategy. Articles that assessed change in BD with estrogen-receptor modulators (tamoxifene [TAM], raloxifene [RLX], and tibolone) and aromatase inhibitors (AIs), as well as cross-sectional and longitudinal studies (LSs) that assessed association between BD and physical activity (PA) or diet were reviewed. Results Ten studies assessed change in BD with TAM; all reported TAM-mediated BD decreases. Change in BD with RLX was assessed by 11 studies; 3 reported a reduction in BD. Effect of tibolone was assessed by 5 RCTs; only 1 reported change in BD. AI-mediated BD reduction was reported by 3 out of 10 studies. The association between PA and BD was assessed by 21 studies; 4 reported an inverse association. The relationship between diet and BD was assessed in 34 studies. All studies on calcium and vitamin D as well as vegetable intake reported an inverse association with BD in premenopausal women. Two RCTs demonstrated BD reduction with a low-fat, high-carbohydrate intervention. Conclusion TAM induces BD reduction; however, the effect of RLX, tibolone, and AIs on BD is unclear. Although data on association between diet and BD in adulthood are contradictory, intake of vegetables, vitamin D, and calcium appear to be associated with lower BD in premenopausal women. PMID:27130722

  3. Comparative study on individual aromatase inhibitors on cardiovascular safety profile: a network meta-analysis

    Directory of Open Access Journals (Sweden)

    Zhao XH

    2015-09-01

    Full Text Available Xihe Zhao,1 Lei Liu,2 Kai Li,1 Wusheng Li,1 Li Zhao,1 Huawei Zou1 1Department of Oncology, 2Department of General Surgery, Shengjing Hospital of China Medical University, Shenyang, People’s Republic of China Abstract: The third-generation aromatase inhibitors (AIs: anastrozole, letrozole, and exemestane have now become standard adjuvant endocrine treatment for postmenopausal estrogen receptor-positive breast cancer complementing chemotherapy and surgery. Because of the absence of direct head-to-head comparisons of these AIs, an indirect comparison is needed for individual treatment choice. In this network systemic assessment, the cardiovascular (CV side effects in using anastrozole, letrozole, and exemestane based on original studies on AIs vs placebo or tamoxifen were compared. We integrated all available direct and indirect evidences. The odds ratio (OR of severe CV events for indirect comparisons between exemestane and anastrozole was 1.41 (95% confidence interval [CI] =0.49–2.78, letrozole and anastrozole was 1.80 (95% CI =0.40–3.92, and letrozole and exemestane was 1.46 (95% CI =0.34–3.4. OR of subgroup risk for AIs and tamoxifen were all >1 except for thrombolism risk subgroup. The results showed that the total and severe CV risk ranking is letrozole, exemestane, and anastrozole in descending order. None of the AIs showed advantages in CV events than tamoxifen except for thromboembolism event incidence. Keywords: CV risk, breast cancer, AI, network meta-analysis

  4. Time course of arthralgia among women initiating aromatase inhibitor therapy and a postmenopausal comparison group in a prospective cohort

    Science.gov (United States)

    Castel, Liana D.; Hartmann, Katherine E.; Mayer, Ingrid A.; Saville, Benjamin R.; Alvarez, JoAnn; Boomershine, Chad S.; Abramson, Vandana G.; Chakravarthy, A. Bapsi; Friedman, Debra L.; Cella, David F.

    2013-01-01

    BACKGROUND More than 80,000 postmenopausal breast cancer patients in the US each year are estimated to begin a five-year course of aromatase inhibitors (AIs) to prevent recurrence. AI-related arthralgia (joint pain and/or stiffness) may contribute to nonadherence, but longitudinal data are needed on arthralgia risk factors, trajectories, and background in postmenopause. OBJECTIVES To describe one-year arthralgia trajectories and baseline covariates among AI patients and a postmenopausal comparison group. METHODS Patients initiating AIs (n=91) were surveyed at the time of AI initiation and at six repeated assessments over one year. A comparison group of postmenopausal women without breast cancer (n=177) completed concomitantly-timed surveys. Numeric rating scales (0–10) were used to measure pain in eight joint pair groups (bilateral fingers, wrists, elbows, shoulders, hips, knees, ankles, and toes). Poisson regression models were used to analyze arthralgia trajectories and risk factors. RESULTS By week six, the AI-initiating group had more severe arthralgia than did the comparison group (ratio of means=1.8, (95% CI 1.2–2.7, p=0.002), adjusting for baseline characteristics. Arthralgia then worsened further over a year in the AI group. Menopausal symptom severity and existing joint-related comorbidity at baseline among women initiating AI were associated with more severe longitudinal arthralgia. CONCLUSIONS Patients initiating AI should be told about the timing of arthralgia over the first year of therapy, and advised that it does not appear to resolve over the course of a year. Menopausal symptoms and joint-related comorbidity at AI initiation can help identify patients at risk for developing AI-related arthralgia. PMID:23575918

  5. QUALITY OF LIFE OF WOMEN RECIEVING ADJUVANT HORMONAL TREATMENT FOR BREAST CANCER – A RANDOMIZED TRIAL COMPARING TAMOXIFEN WITH AROMATASE INHIBITORS

    Directory of Open Access Journals (Sweden)

    C. Volovat

    2011-05-01

    Full Text Available Purpose: The assessment and comparison of the quality of life in women with early stages breast cancer receiving Tamoxifen versus aromatase inhibitors (AINs. Methods: There were selected 223 patients treated at Center of Medical Oncology Iasi, with early stages breast cancer. The patients were divided in two groups: 115 patients receiving Tamoxifen and 107 patients receiving aromatase inhibitors. From the patients receiving AINs, 33 of patients have received Exemestane, 60 patients Letrozole and 14 patients Anastrazole. The patients have completed an EORTC C30 and EORTC BR23 questionnaire at the beginning of the treatment (after one month and after 2 years of treatment. There was calculated the difference related with global status, functional scales, emotional scales, cognitive scales and symptom scales. Results: Statistic results show a better quality of life for Anastrazole vs. Letrozole and for AINs vs. Tamoxifen group, mainly on physical scales both after 2 months and after 2 years of treatment. In the same time, the physical scales were with better results after 1 month of treatment vs. 2 years of treatment. Conclusions: Following the hormonal treatment period, there is a mild worsening of quality of life for Tamoxifen and AINs too. In the same time, the quality of life is better in the group with AINs treatment comparative with the Tamoxifen treatment.

  6. Targeted Metabolomics Approach To Detect the Misuse of Steroidal Aromatase Inhibitors in Equine Sports by Biomarker Profiling.

    Science.gov (United States)

    Chan, George Ho Man; Ho, Emmie Ngai Man; Leung, David Kwan Kon; Wong, Kin Sing; Wan, Terence See Ming

    2016-01-01

    The use of anabolic androgenic steroids (AAS) is prohibited in both human and equine sports. The conventional approach in doping control testing for AAS (as well as other prohibited substances) is accomplished by the direct detection of target AAS or their characteristic metabolites in biological samples using hyphenated techniques such as gas chromatography or liquid chromatography coupled with mass spectrometry. Such an approach, however, falls short when dealing with unknown designer steroids where reference materials and their pharmacokinetics are not available. In addition, AASs with fast elimination times render the direct detection approach ineffective as the detection window is short. A targeted metabolomics approach is a plausible alternative to the conventional direct detection approach for controlling the misuse of AAS in sports. Because the administration of AAS of the same class may trigger similar physiological responses or effects in the body, it may be possible to detect such administrations by monitoring changes in the endogenous steroidal expression profile. This study attempts to evaluate the viability of using the targeted metabolomics approach to detect the administration of steroidal aromatase inhibitors, namely androst-4-ene-3,6,17-trione (6-OXO) and androsta-1,4,6-triene-3,17-dione (ATD), in horses. Total (free and conjugated) urinary concentrations of 31 endogenous steroids were determined by gas chromatography-tandem mass spectrometry for a group of 2 resting and 2 in-training thoroughbred geldings treated with either 6-OXO or ATD. Similar data were also obtained from a control (untreated) group of in-training thoroughbred geldings (n = 28). Statistical processing and chemometric procedures using principle component analysis and orthogonal projection to latent structures-discriminant analysis (OPLS-DA) have highlighted 7 potential biomarkers that could be used to differentiate urine samples obtained from the control and the treated groups

  7. Screening of selected pesticides for inhibition of CYP19 aromatase activity in vitro

    DEFF Research Database (Denmark)

    Vinggaard, A.M.; Hnida, C.; Breinholt, V.;

    2000-01-01

    Many pesticides are able to block or activate the steroid hormone receptors and/or to affect the levels of sex hormones, thereby potentially affecting the development or expression of the male and female reproductive system or both. This emphasizes the relevance of screening pesticides for a wide...... range of hormone-mimicking effects. Twenty-two pesticides were tested for their ability to affect CYP19 aromatase activity in human placental microsomes using the classical [H-3](2)O method. Prochloraz, imazalil, propioconazole, fenarimol, triadimenol, triadimefon tall fungicides), and dicofol tan...... triadimenol were identified as weak aromatase inhibitors. In conclusion, seven out of 22 tested pesticides turned out to be weak to moderate aromatase inhibitors in vitro, indicating the relevance of elucidating the endocrine effects in vivo of these compounds....

  8. Currently used pesticides and their mixtures affect the function of sex hormone receptors and aromatase enzyme activity

    Energy Technology Data Exchange (ETDEWEB)

    Kjeldsen, Lisbeth Stigaard; Ghisari, Mandana; Bonefeld-Jørgensen, Eva Cecilie, E-mail: ebj@mil.au.dk

    2013-10-15

    The endocrine-disrupting potential of pesticides is of health concern, since they are found ubiquitously in the environment and in food items. We investigated in vitro effects on estrogen receptor (ER) and androgen receptor (AR) transactivity, and aromatase enzyme activity, of the following pesticides: 2-methyl-4-chlorophenoxyacetic acid (MCPA), terbuthylazine, iodosulfuron-methyl-sodium, mesosulfuron-methyl, metsulfuron-methyl, chlormequat chloride, bitertanol, propiconazole, prothioconazole, mancozeb, cypermethrin, tau fluvalinate, malathion and the metabolite ethylene thiourea (ETU). The pesticides were analyzed alone and in selected mixtures. Effects of the pesticides on ER and AR function were assessed in human breast carcinoma MVLN cells and hamster ovary CHO-K1 cells, respectively, using luciferase reporter gene assays. Effects on aromatase enzyme activity were analyzed in human choriocarcinoma JEG-3 cells, employing the classical [{sup 3}H]{sub 2}O method. Five pesticides (terbuthylazine, propiconazole, prothioconazole, cypermethrin and malathion) weakly induced the ER transactivity, and three pesticides (bitertanol, propiconazole and mancozeb) antagonized the AR activity in a concentration-dependent manner. Three pesticides (terbuthylazine, propiconazole and prothioconazole) weakly induced the aromatase activity. In addition, two mixtures, consisting of three pesticides (bitertanol, propiconazole, cypermethrin) and five pesticides (terbuthylazine, bitertanol, propiconazole, cypermethrin, malathion), respectively, induced the ER transactivity and aromatase activity, and additively antagonized the AR transactivity. In conclusion, our data suggest that currently used pesticides possess endocrine-disrupting potential in vitro which can be mediated via ER, AR and aromatase activities. The observed mixture effects emphasize the importance of considering the combined action of pesticides in order to assure proper estimations of related health effect risks

  9. Currently used pesticides and their mixtures affect the function of sex hormone receptors and aromatase enzyme activity

    International Nuclear Information System (INIS)

    The endocrine-disrupting potential of pesticides is of health concern, since they are found ubiquitously in the environment and in food items. We investigated in vitro effects on estrogen receptor (ER) and androgen receptor (AR) transactivity, and aromatase enzyme activity, of the following pesticides: 2-methyl-4-chlorophenoxyacetic acid (MCPA), terbuthylazine, iodosulfuron-methyl-sodium, mesosulfuron-methyl, metsulfuron-methyl, chlormequat chloride, bitertanol, propiconazole, prothioconazole, mancozeb, cypermethrin, tau fluvalinate, malathion and the metabolite ethylene thiourea (ETU). The pesticides were analyzed alone and in selected mixtures. Effects of the pesticides on ER and AR function were assessed in human breast carcinoma MVLN cells and hamster ovary CHO-K1 cells, respectively, using luciferase reporter gene assays. Effects on aromatase enzyme activity were analyzed in human choriocarcinoma JEG-3 cells, employing the classical [3H]2O method. Five pesticides (terbuthylazine, propiconazole, prothioconazole, cypermethrin and malathion) weakly induced the ER transactivity, and three pesticides (bitertanol, propiconazole and mancozeb) antagonized the AR activity in a concentration-dependent manner. Three pesticides (terbuthylazine, propiconazole and prothioconazole) weakly induced the aromatase activity. In addition, two mixtures, consisting of three pesticides (bitertanol, propiconazole, cypermethrin) and five pesticides (terbuthylazine, bitertanol, propiconazole, cypermethrin, malathion), respectively, induced the ER transactivity and aromatase activity, and additively antagonized the AR transactivity. In conclusion, our data suggest that currently used pesticides possess endocrine-disrupting potential in vitro which can be mediated via ER, AR and aromatase activities. The observed mixture effects emphasize the importance of considering the combined action of pesticides in order to assure proper estimations of related health effect risks. - Highlights:

  10. Paradoxal metabolic flare detected by 18F-fluorodeoxyglucose positron emission tomography in a patient with metastatic breast cancer treated with aromatase inhibitor and biphosphonate

    International Nuclear Information System (INIS)

    Patients with estrogen-receptor-positive advanced breast cancer are treated with endocrine therapy. The majority of breast cancer localizations show 18F-fluorodeoxyglucose (FDG) uptake at positron emission tomography (PET) examination. In these patients, the metabolic flare after therapy is common and was proposed as an index of therapy efficacy. Nevertheless, prolonged persistence of flare can lead to misinterpretation. We describe a case of a patient with invasive ductal breast cancer with bone metastases at bone scintigraphy and FDG PET scan and with expression of estrogen receptors. Initially, the patient underwent endocrine therapy in addition to a biphosfonate. Owing to progression observed in a bone scan, Tamoxifen was substituted with aromatase inhibitors. Successive bone scan examinations showed stabilization with a marked clinical improvement. A second FDG PET was performed 28 months after the first examination and showed a metabolic flare phenomenon with concomitant partial calcification of osteolitic lesions. This is an unusual case of prolonged metabolic flare

  11. The time since last menstrual period is important as a clinical predictor for non-steroidal aromatase inhibitor-related arthralgia

    International Nuclear Information System (INIS)

    The clinical predictors of aromatase inhibitor-related arthralgia (AIA), a drug-related adverse reaction of aromatase inhibitors (AIs), remain unclear. AIA was prospectively surveyed every 4 months in 328 postmenopausal breast cancer patients administered a non-steroidal AI (anastrozole). Various clinicopathological parameters were recorded and analyzed (chi-square test, Fisher's exact test and logistic regression analysis). The mean observation period was 39.9 months. AIA manifested in 114 patients (34.8%), with peaks of onset at 4 (33.7%) and 8 months (11.4%) after starting AI administration. Some cases manifested even after 13 months. AIA tended to occur in younger patients (incidences of 46.3%, 37.4% and 28.0% for ages of < 55, 55-65 and > 65 years, respectively (p = 0.063)) and decreased significantly with the age at menarche (53.3%, 35.3% and 15.4% for < 12, 12-15 and > 15 years, respectively (p = 0.036)). The incidences were 45.1%, 46.3 and 25.1% for the time since the last menstrual period (LMP) < 5 years, 5-10 years and > 10 years, being significantly lower at > 10 years (p < 0.001). In logistic regression analysis, the AIA incidence was significantly lower in the time since LMP > 10-year group versus the < 5-year group (odds ratio 0.44, p = 0.002), but the age at menarche showed no association. AIA manifested significantly earlier (≤ 6 months) as the time since LMP became shorter (< 5 years). AIA tends to manifest early after starting AI, but some cases show delayed onset. The incidence was significantly lower in patients with a duration of > 10 years since LMP. When the time since LMP was short, the onset of AIA was significantly earlier after starting AI administration

  12. A systematic review and methodological evaluation of published cost-effectiveness analyses of aromatase inhibitors versus tamoxifen in early stage breast cancer.

    Directory of Open Access Journals (Sweden)

    Ava A John-Baptiste

    Full Text Available BACKGROUND: A key priority in developing policies for providing affordable cancer care is measuring the value for money of new therapies using cost-effectiveness analyses (CEAs. For CEA to be useful it should focus on relevant outcomes and include thorough investigation of uncertainty. Randomized controlled trials (RCTs of five years of aromatase inhibitors (AI versus five years of tamoxifen in the treatment of post-menopausal women with early stage breast cancer, show benefit of AI in terms of disease free survival (DFS but not overall survival (OS and indicate higher risk of fracture with AI. Policy-relevant CEA of AI versus tamoxifen should focus on OS and include analysis of uncertainty over key assumptions. METHODS: We conducted a systematic review of published CEAs comparing an AI to tamoxifen. We searched Ovid MEDLINE, EMBASE, PsychINFO, and the Cochrane Database of Systematic Reviews without language restrictions. We selected CEAs with outcomes expressed as cost per life year or cost per quality adjusted life year (QALY. We assessed quality using the Neumann checklist. Using structured forms two abstractors collected descriptive information, sources of data, baseline assumptions on effectiveness and adverse events, and recorded approaches to assessing parameter uncertainty, methodological uncertainty, and structural uncertainty. RESULTS: We identified 1,622 citations and 18 studies met inclusion criteria. All CE estimates assumed a survival benefit for aromatase inhibitors. Twelve studies performed sensitivity analysis on the risk of adverse events and 7 assumed no additional mortality risk with any adverse event. Sub-group analysis was limited; 6 studies examined older women, 2 examined women with low recurrence risk, and 1 examined women with multiple comorbidities. CONCLUSION: Published CEAs comparing AIs to tamoxifen assumed an OS benefit though none has been shown in RCTs, leading to an overestimate of the cost-effectiveness of AIs

  13. Complementary or alternative medicine as possible determinant of decreased persistence to aromatase inhibitor therapy among older women with non-metastatic breast cancer.

    Directory of Open Access Journals (Sweden)

    Laetitia Huiart

    Full Text Available PURPOSE: Aromatase inhibitor therapy (AI significantly improves survival in breast cancer patients. Little is known about adherence and persistence to aromatase inhibitors and about the causes of treatment discontinuation among older women. METHODS: We constituted a cohort of women over 65 receiving a first AI therapy for breast cancer between 2006 and 2008, and followed them until June 2011. Women were selected in the population-based French National Health Insurance databases, and data was collected on the basis of pharmacy refills, medical records and face-to-face interviews. Non-persistence to treatment was defined as the first treatment discontinuation lasting more than 3 consecutive months. Time to treatment discontinuation was studied using survival analysis techniques. RESULTS: Overall among the 382 selected women, non-persistence to treatment went from 8.7% (95%CI: 6.2-12.1 at 1 year, to 15.6% (95%CI: 12.2-19.8 at 2 years, 20.8% (95%CI: 16.7-25.6 at 3 years, and 24.7% (95%CI: 19.5-31.0 at 4 years. In the multivariate analysis on a sub-sample of 233 women with available data, women using complementary or alternative medicine (CAM (HR = 3.2; 95%CI: 1.5-6.9 or suffering from comorbidities (HR = 2.2; 95%CI: 1.0-4.8 were more likely to discontinue their treatment, whereas women with polypharmacy (HR = 0.4; 95%CI: 0.2-0.91 were less likely to discontinue. In addition, 13% of the women with positive hormonal receptor status did not fill any prescription for anti-hormonal therapy. CONCLUSION: AI therapy is discontinued prematurely in a substantial portion of older patients. Some patients may use CAM not as a complementary treatment, but as an alternative to conventional medicine. Improving patient-physician communication on the use of CAM may improve hormonal therapy adherence.

  14. Effects of selective serotonin reuptake inhibitors on three sex steroids in two versions of the aromatase enzyme inhibition assay and in the H295R cell assay

    DEFF Research Database (Denmark)

    Jacobsen, Naja Wessel; Hansen, Cecilie Hurup; Nellemann, Christine;

    2015-01-01

    shown to inhibit the aromatase enzyme in both types of aromatase assays. The IC50 values ranged from 3 to 600μM. All five SSRIs, were further investigated in the H295R cell line. All compounds altered the steroid secretion from the cells, the lowest observed effect levels were 0.9μM and 3.1μ...

  15. 芳香化酶抑制剂致骨质疏松研究进展%Research of aromatase inhibitor induced osteoporosis

    Institute of Scientific and Technical Information of China (English)

    马翠翠

    2008-01-01

    Breast cancer patients treated by aromatase inhibitor(AI) may cause ovarian failure, resulting in decreased hormone levels. Then bone loss increases, which may result in thinning bone and osteoporosis. In clinic, attention should be given and appropriate means must be chosen to prevent and treat this disease. Calcium + vitamin D, diphosphonate, selective estrogen receptor modulator, Chinese medicine are recommen-ded to reduce the incidence of esteoporosis.%乳腺癌患者服用芳香化酶抑制剂(AI)使得卵巢功能缺失导致体内雌激素水平下降,从而加速骨代谢发生骨质疏松.在临床中应给予重视并根据具体情况选择适当防治手段.推荐使用钙剂+维生素D、双膦酸盐、选择性雌激素受体调节剂、中药等药物治疗,减少骨质疏松的发病率.

  16. Inhibition of human CYP19 by azoles used as antifungal agents and aromatase inhibitors, using a new LC-MS/MS method for the analysis of estradiol product formation

    International Nuclear Information System (INIS)

    Azoles are used as fungicides in agriculture or antifungal drugs in medicine. Their therapeutic activity is based on the inhibition of fungal lanosterol-14α-demethylase (CYP51). Azoles are also used for the treatment of estrogen-dependent diseases, e.g. in breast cancer therapy. Inhibition of CYP19 (aromatase) is the working principle for tumor therapy, but is an unwanted side effect of azoles used as fungicides or antifungal drugs. The inhibition of recombinant human CYP19 by 21 azoles in use for the three different purposes was investigated using the natural substrate testosterone. Estradiol product formation was measured by a newly developed and fully validated analytical method based on liquid chromatography-tandem mass spectrometry utilizing photospray ionization (APPI). Potency of enzyme inhibition was expressed in terms of IC5 concentrations. The two cytostatic drugs fadrozole and letrozole were the most potent inhibitors. However, azoles used as fungicides, e.g. prochloraz, or as antifungal drugs, e.g. bifonazole, were almost as potent inhibitors of aromatase as the drugs used in tumor therapy. Comparison of plasma concentrations that may be reached in antifungal therapy do not allow for large safety factors for bifonazole and miconazole. The IC5 values were compared to data obtained with other substrates, such as the pseudo-substrate dibenzylfluorescein (DBF). A high correlation was found, indicating that the fluorescence assay with DBF can well be used for potency ranking and screening of chemicals for aromatase inhibition. The data for antifungal drugs show that side effects on steroid hormone synthesis in humans due to inhibition of aromatase should be considered

  17. Unique Distribution of Aromatase in the Human Brain: In Vivo Studies With PET and [N-Methyl-11C]Vorozole

    Energy Technology Data Exchange (ETDEWEB)

    Biegon, A.; Biegon, A.; Kim, S.W.; Alexoff, D.; Millard, J.; Carter, P.; Hubbard, B.; King, P.; Logan, J.; Muench, L.; Pareto, D.; Schlyer, D.; Shea, C.; Telang, F.; Wang, G.-J.; Xu, Y.; Fowler, J.

    2010-10-01

    Aromatase catalyzes the last step in estrogen biosynthesis. Brain aromatase is involved in diverse neurophysiological and behavioral functions including sexual behavior, aggression, cognition, and neuroprotection. Using positron emission tomography (PET) with the radiolabeled aromatase inhibitor [N-methyl-{sup 11}C]vorozole, we characterized the tracer distribution and kinetics in the living human brain. Six young, healthy subjects, three men and three women, were administered the radiotracer alone on two separate occasions. Women were scanned in distinct phases of the menstrual cycle. Specificity was confirmed by pretreatment with a pharmacological (2.5 mg) dose of the aromatase inhibitor letrozole. PET data were acquired over a 90-min period and regions of interest placed over selected brain regions. Brain and plasma time activity curves, corrected for metabolites, were used to derive kinetic parameters. Distribution volume (V{sub T}) values in both men and women followed the following rank order: thalamus > amygdala = preoptic area > medulla (inferior olive) > accumbens, pons, occipital and temporal cortex, putamen, cerebellum, and white matter. Pretreatment with letrozole reduced VT in all regions, though the size of the reduction was region-dependent, ranging from {approx}70% blocking in thalamus andpreoptic area to {approx}10% in cerebellum. The high levels of aromatase in thalamus and medulla (inferior olive) appear to be unique to humans. These studies set the stage for the noninvasive assessment of aromatase involvement in various physiological and pathological processes affecting the human brain.

  18. Effects of 17α-Methyltestosterone and Aromatase Inhibitor Letrozole on Sex Reversal, Gonadal Structure, and Growth in Yellow Catfish Pelteobagrus fulvidraco.

    Science.gov (United States)

    Shen, Zhi-Gang; Fan, Qi-Xue; Yang, Wei; Zhang, Yun-Long; Wang, Han-Ping

    2015-04-01

    Monosex populations are in demand in many fish species with sexual dimorphism, e.g., better growth performance, higher gonad value, superior ornamental value. From the point of view of research, a monosex population is one of the best materials for investigating sex-determining mechanisms, sex differentiation, and sex-linked markers. Sex reversal of females (phenotypic reversal from XX female to XX male) is the first step in all-female production in species with an XX/XY system for sex determination. In the present study, masculinization of yellow catfish, a species with XX/XY sex determination, was investigated by oral administration of various doses of 17α-methyltestosterone (MT) or an aromatase inhibitor (AI) letrozole (LZ); effects on survival, growth performance, sex ratio, and changes in gonadal structure were evaluated. Three doses (20, 50, and 100 mg kg(-1) diet) of oral MT or LZ were administered to fry from 10 days post-hatching (DPH) to 59 DPH. Oral administration of MT at all doses did not significantly change the ratio of males (45.8%, 33.3%, and 50.0% respectively) compared to the control group (37.5%), while yielding intersex fish at all doses (4.2% to 8.3%). Oral administration of LZ produced a significantly higher proportion of males in all doses (75.5%, 83.3%, and 75.0%, respectively). Additionally, the lowest dose of LZ improved the growth of treated fish compared to the control, and all doses of LZ enhanced spermatogenesis in treated males. PMID:25920714

  19. miR-155 Drives Metabolic Reprogramming of ER+ Breast Cancer Cells Following Long-Term Estrogen Deprivation and Predicts Clinical Response to Aromatase Inhibitors.

    Science.gov (United States)

    Bacci, Marina; Giannoni, Elisa; Fearns, Antony; Ribas, Ricardo; Gao, Qiong; Taddei, Maria Letizia; Pintus, Gianfranco; Dowsett, Mitch; Isacke, Clare M; Martin, Lesley-Ann; Chiarugi, Paola; Morandi, Andrea

    2016-03-15

    Aromatase inhibitors (AI) have become the first-line endocrine treatment of choice for postmenopausal estrogen receptor-positive (ER(+)) breast cancer patients, but resistance remains a major challenge. Metabolic reprogramming is a hallmark of cancer and may contribute to drug resistance. Here, we investigated the link between altered breast cancer metabolism and AI resistance using AI-resistant and sensitive breast cancer cells, patient tumor samples, and AI-sensitive human xenografts. We found that long-term estrogen deprivation (LTED), a model of AI resistance, was associated with increased glycolysis dependency. Targeting the glycolysis-priming enzyme hexokinase-2 (HK2) in combination with the AI, letrozole, synergistically reduced cell viability in AI-sensitive models. Conversely, MCF7-LTED cells, which displayed a high degree of metabolic plasticity, switched to oxidative phosphorylation when glycolysis was impaired. This effect was ER dependent as breast cancer cells with undetectable levels of ER failed to exhibit metabolic plasticity. MCF7-LTED cells were also more motile than their parental counterparts and assumed amoeboid-like invasive abilities upon glycolysis inhibition with 2-deoxyglucose (2-DG). Mechanistic investigations further revealed an important role for miR-155 in metabolic reprogramming. Suppression of miR-155 resulted in sensitization of MCF7-LTED cells to metformin treatment and impairment of 2-DG-induced motility. Notably, high baseline miR-155 expression correlated with poor response to AI therapy in a cohort of ER(+) breast cancers treated with neoadjuvant anastrozole. These findings suggest that miR-155 represents a biomarker potentially capable of identifying the subset of breast cancers most likely to adapt to and relapse on AI therapy. PMID:26795347

  20. Two natural products, trans-phytol and (22E)-ergosta-6,9,22-triene-3β,5α,8α-triol, inhibit the biosynthesis of estrogen in human ovarian granulosa cells by aromatase (CYP19)

    International Nuclear Information System (INIS)

    Aromatase is the only enzyme in vertebrates to catalyze the biosynthesis of estrogens. Although inhibitors of aromatase have been developed for the treatment of estrogen-dependent breast cancer, the whole-body inhibition of aromatase causes severe adverse effects. Thus, tissue-selective aromatase inhibitors are important for the treatment of estrogen-dependent cancers. In this study, 63 natural products with diverse structures were examined for their effects on estrogen biosynthesis in human ovarian granulosa-like KGN cells. Two compounds—trans-phytol (SA-20) and (22E)-ergosta-6,9,22-triene-3β,5α,8α-triol (SA-48)—were found to potently inhibit estrogen biosynthesis (IC50: 1 μM and 0.5 μM, respectively). Both compounds decreased aromatase mRNA and protein expression levels in KGN cells, but had no effect on the aromatase catalytic activity in aromatase-overexpressing HEK293A cells and recombinant expressed aromatase. The two compounds decreased the expression of aromatase promoter I.3/II. Neither compound affected intracellular cyclic AMP (cAMP) levels, but they inhibited the phosphorylation or protein expression of cAMP response element-binding protein (CREB). The effects of these two compounds on extracellular regulated kinase (ERK), c-Jun N-terminal kinase (JNK), p38 mitogen-activated protein kinases (MAPKs), and AKT/phosphoinositide 3-kinase (PI3K) pathway were examined. Inhibition of p38 MAPK could be the mechanism underpinning the actions of these compounds. Our results suggests that natural products structurally similar to SA-20 and SA-48 may be a new source of tissue-selective aromatase modulators, and that p38 MAPK is important in the basal control of aromatase in ovarian granulosa cells. SA-20 and SA-48 warrant further investigation as new pharmaceutical tools for the prevention and treatment of estrogen-dependent cancers. - Highlights: • Two natural products inhibited estrogen biosynthesis in human ovarian granulosa cells. • They inhibited

  1. Two natural products, trans-phytol and (22E)-ergosta-6,9,22-triene-3β,5α,8α-triol, inhibit the biosynthesis of estrogen in human ovarian granulosa cells by aromatase (CYP19)

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Jiajia [Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu (China); Yuan, Yun [Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu (China); School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang (China); Lu, Danfeng; Du, Baowen [Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu (China); Xiong, Liang; Shi, Jiangong [State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Yang, Lijuan [Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu (China); Liu, Wanli [MOE Key Laboratory of Protein Science, School of Life Sciences, Tsinghua University, Beijing 100084 (China); Yuan, Xiaohong [School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang (China); Zhang, Guolin, E-mail: zhanggl@cib.ac.cn [Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu (China); Chinese Academy of Sciences Sichuan Translational Medicine Research Hospital, Chengdu (China); Wang, Fei, E-mail: wangfei@cib.ac.cn [Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu (China); Chinese Academy of Sciences Sichuan Translational Medicine Research Hospital, Chengdu (China)

    2014-08-15

    Aromatase is the only enzyme in vertebrates to catalyze the biosynthesis of estrogens. Although inhibitors of aromatase have been developed for the treatment of estrogen-dependent breast cancer, the whole-body inhibition of aromatase causes severe adverse effects. Thus, tissue-selective aromatase inhibitors are important for the treatment of estrogen-dependent cancers. In this study, 63 natural products with diverse structures were examined for their effects on estrogen biosynthesis in human ovarian granulosa-like KGN cells. Two compounds—trans-phytol (SA-20) and (22E)-ergosta-6,9,22-triene-3β,5α,8α-triol (SA-48)—were found to potently inhibit estrogen biosynthesis (IC{sub 50}: 1 μM and 0.5 μM, respectively). Both compounds decreased aromatase mRNA and protein expression levels in KGN cells, but had no effect on the aromatase catalytic activity in aromatase-overexpressing HEK293A cells and recombinant expressed aromatase. The two compounds decreased the expression of aromatase promoter I.3/II. Neither compound affected intracellular cyclic AMP (cAMP) levels, but they inhibited the phosphorylation or protein expression of cAMP response element-binding protein (CREB). The effects of these two compounds on extracellular regulated kinase (ERK), c-Jun N-terminal kinase (JNK), p38 mitogen-activated protein kinases (MAPKs), and AKT/phosphoinositide 3-kinase (PI3K) pathway were examined. Inhibition of p38 MAPK could be the mechanism underpinning the actions of these compounds. Our results suggests that natural products structurally similar to SA-20 and SA-48 may be a new source of tissue-selective aromatase modulators, and that p38 MAPK is important in the basal control of aromatase in ovarian granulosa cells. SA-20 and SA-48 warrant further investigation as new pharmaceutical tools for the prevention and treatment of estrogen-dependent cancers. - Highlights: • Two natural products inhibited estrogen biosynthesis in human ovarian granulosa cells. • They

  2. Vitamin D and aromatase inhibitor-induced musculoskeletal symptoms (AIMSS): a phase II, double-blind, placebo-controlled, randomized trial.

    Science.gov (United States)

    Rastelli, Antonella L; Taylor, Marie E; Gao, Feng; Armamento-Villareal, Reina; Jamalabadi-Majidi, Shohreh; Napoli, Nicola; Ellis, Matthew J

    2011-08-01

    A double-blind placebo-controlled randomized phase II trial was performed to determine whether High Dose Vitamin D2 supplementation (HDD) in women receiving adjuvant anastrozole improves aromatase inhibitor-induced musculoskeletal symptoms (AIMSS) and bone loss. Patients with early breast cancer and AIMSS were stratified according to their baseline 25-hydroxy vitamin D (25OHD) level. Stratum A (20-29 ng/ml) received either HDD 50,000 IU capsules weekly for 8 weeks then monthly for 4 months or placebo. Stratum B (10-19 ng/ml) received either HDD for 16 weeks and then monthly for 2 months, or placebo. AIMSS was assessed by the Brief Pain Inventory-Short Form (BPI-SF), the Fibromyalgia Impact Questionnaire (FIQ), and the Health Assessment Questionnaire-Disability Index (HAQ-DI) at baseline, 2, 4, and 6 months. Bone Mineral Density (BMD) was measured at baseline and at 6 months. The primary endpoint of the study was the change-from-baseline musculoskeletal pain. The secondary endpoint was the percent change in BMD at 6 months. Sixty women were enrolled. Baseline characteristics were comparable between the groups. At 2 months, FIQ pain (P = 0.0045), BPI worst-pain (P = 0.04), BPI average-pain (P = 0.0067), BPI pain-severity (P = 0.04), and BPI interference (P = 0.034) scores were better in the HDD than placebo group. The positive effect of HDD on AIMSS was stronger across all time points in Stratum B than Stratum A (FIQ pain, P = 0.04; BPI average, P = 0.03; BPI severity, P = 0.03; BPI interference, P = 0.04). BMD at the femoral neck decreased in the placebo and did not change in the HDD group (P = 0.06). Weekly HDD improves AIMSS and may have a positive effect on bone health. Vitamin D supplementation strategies for breast cancer patients on AI should be further investigated. PMID:21691817

  3. Combining Computational and Biochemical Studies for a Rationale on the Anti-Aromatase Activity of Natural Polyphenols

    OpenAIRE

    Neves, Marco A. C.; Dinis, Teresa C. P.; Colombo, Giorgio; Melo, M. Luísa Sá e

    2007-01-01

    Aromatase, an enzyme of the cytochrome P450 family, is a very important pharmacological target, particularly for the treatment of breast cancer. The anti-aromatase activity of a set of natural polyphenolic compounds was evaluated in vitro. Strong aromatase inhibitors including flavones, flavanones, resveratrol, and oleuropein, with activities comparable to that of the reference anti-aromatase drug aminoglutethimide, were identified. Through the application of molecular modeling techniques bas...

  4. Origin of aromatase inhibitory activity via proteochemometric modeling.

    Science.gov (United States)

    Simeon, Saw; Spjuth, Ola; Lapins, Maris; Nabu, Sunanta; Anuwongcharoen, Nuttapat; Prachayasittikul, Virapong; Wikberg, Jarl E S; Nantasenamat, Chanin

    2016-01-01

    Aromatase, the rate-limiting enzyme that catalyzes the conversion of androgen to estrogen, plays an essential role in the development of estrogen-dependent breast cancer. Side effects due to aromatase inhibitors (AIs) necessitate the pursuit of novel inhibitor candidates with high selectivity, lower toxicity and increased potency. Designing a novel therapeutic agent against aromatase could be achieved computationally by means of ligand-based and structure-based methods. For over a decade, we have utilized both approaches to design potential AIs for which quantitative structure-activity relationships and molecular docking were used to explore inhibitory mechanisms of AIs towards aromatase. However, such approaches do not consider the effects that aromatase variants have on different AIs. In this study, proteochemometrics modeling was applied to analyze the interaction space between AIs and aromatase variants as a function of their substructural and amino acid features. Good predictive performance was achieved, as rigorously verified by 10-fold cross-validation, external validation, leave-one-compound-out cross-validation, leave-one-protein-out cross-validation and Y-scrambling tests. The investigations presented herein provide important insights into the mechanisms of aromatase inhibitory activity that could aid in the design of novel potent AIs as breast cancer therapeutic agents. PMID:27190705

  5. Proton pump inhibitors affect the gut microbiome

    NARCIS (Netherlands)

    Imhann, Floris; Bonder, Marc Jan; Vich Vila, Arnau; Fu, Jingyuan; Mujagic, Zlatan; Vork, Lisa; Tigchelaar, Ettje F; Jankipersadsing, Soesma A; Cenit, Maria Carmen; Harmsen, Hermie J M; Dijkstra, Gerard; Franke, Lude; Xavier, Ramnik J; Jonkers, Daisy; Wijmenga, Cisca; Weersma, Rinse K; Zhernakova, Alexandra

    2015-01-01

    BACKGROUND AND AIMS: Proton pump inhibitors (PPIs) are among the top 10 most widely used drugs in the world. PPI use has been associated with an increased risk of enteric infections, most notably Clostridium difficile. The gut microbiome plays an important role in enteric infections, by resisting or

  6. Potential utility of natural products as regulators of breast cancer-associated aromatase promoters

    Directory of Open Access Journals (Sweden)

    Walker Larry A

    2011-06-01

    Full Text Available Abstract Aromatase, the key enzyme in estrogen biosynthesis, converts androstenedione to estrone and testosterone to estradiol. The enzyme is expressed in various tissues such as ovary, placenta, bone, brain, skin, and adipose tissue. Aromatase enzyme is encoded by a single gene CYP 19A1 and its expression is controlled by tissue-specific promoters. Aromatase mRNA is primarily transcribed from promoter I.4 in normal breast tissue and physiological levels of aromatase are found in breast adipose stromal fibroblasts. Under the conditions of breast cancer, as a result of the activation of a distinct set of aromatase promoters (I.3, II, and I.7 aromatase expression is enhanced leading to local overproduction of estrogen that promotes breast cancer. Aromatase is considered as a potential target for endocrine treatment of breast cancer but due to nonspecific reduction of aromatase activity in other tissues, aromatase inhibitors (AIs are associated with undesirable side effects such as bone loss, and abnormal lipid metabolism. Inhibition of aromatase expression by inactivating breast tumor-specific aromatase promoters can selectively block estrogen production at the tumor site. Although several synthetic chemical compounds and nuclear receptor ligands are known to inhibit the activity of the tumor-specific aromatase promoters, further development of more specific and efficacious drugs without adverse effects is still warranted. Plants are rich in chemopreventive agents that have a great potential to be used in chemotherapy for hormone dependent breast cancer which could serve as a source for natural AIs. In this brief review, we summarize the studies on phytochemicals such as biochanin A, genistein, quercetin, isoliquiritigenin, resveratrol, and grape seed extracts related to their effect on the activation of breast cancer-associated aromatase promoters and discuss their aromatase inhibitory potential to be used as safer chemotherapeutic agents for

  7. Aromatase: Contributions to Physiology and Disease in Women and Men.

    Science.gov (United States)

    Blakemore, Jennifer; Naftolin, Fredrick

    2016-07-01

    Aromatase (estrogen synthetase; EC 1.14.14.1) catalyzes the demethylation of androgens' carbon 19, producing phenolic 18-carbon estrogens. Aromatase is most widely known for its roles in reproduction and reproductive system diseases, and as a target for inhibitor therapy in estrogen-sensitive diseases including cancer, endometriosis, and leiomyoma (141, 143). However, all tissues contain estrogen receptor-expressing cells, the majority of genes have a complete or partial estrogen response element that regulates their expression (61), and there are plentiful nonreceptor effects of estrogens (79); therefore, the effect of aromatase through the provision of estrogen is almost universal in terms of health and disease. This review will provide a brief but comprehensive overview of the enzyme, its role in steroidogenesis, the problems that arise with its functional mutations and mishaps, the roles in human physiology of aromatase and its product estrogens, its current clinical roles, and the effects of aromatase inhibitors. While much of the story is that of the consequences of the formation of its product estrogens, we also will address alternative enzymatic roles of aromatase as a demethylase or nonenzymatic actions of this versatile molecule. Although this short review is meant to be thorough, it is by no means exhaustive; rather, it is meant to reflect the cutting-edge, exciting properties and possibilities of this ancient enzyme and its products. PMID:27252161

  8. Modulation of Δ9-tetrahydrocannabinol-induced MCF-7 breast cancer cell growth by cyclooxygenase and aromatase

    International Nuclear Information System (INIS)

    Δ9-Tetrahydrocannabinol (Δ9-THC), a major constituent of marijuana, has been shown to stimulate the growth of MCF-7 breast cancer cells through cannabinoid receptor-independent signaling [Takeda, S., Yamaori, S., Motoya, E., Matsunaga, T., Kimura, T., Yamamoto, I., Watanabe, K., 2008. Δ9-Tetrahydrocannabinol enhances MCF-7 cell proliferation via cannabinoid receptor-independent signaling. Toxicology 245, 141-146]. Although the growth of MCF-7 cells is known to be stimulated by 17β-estradiol (E2), the interaction of Δ9-THC and E2 in MCF-7 cell growth is not fully clarified so far. In the present study, by using E2-sensitive MCF-7 cells that have expressed cyclooxygenase-2 (COX-2) and cytochrome P450 19 (aromatase), we studied whether or not COX-2 and aromatase are involved in Δ9-THC-mediated MCF-7 cell proliferation. It was shown that Δ9-THC-induced MCF-7 cell growth was inhibited by COX-2 inhibitors and was stimulated by arachidonic acid (a COX substrate). However, the growth of MCF-7 cells induced by Δ9-THC was not stimulated by PGE2, and the expression of aromatase was not affected by COX-2 inhibitors, arachidonic acid, and PGE2, suggesting that there is a disconnection between COX-2 (PGE2) and aromatase in Δ9-THC-mediated MCF-7 cell proliferation. On the other hand, Δ9-THC-induced MCF-7 cell growth was elevated by two kinds of aromatase inhibitors. Taken together with the evidence that Δ9-THC-induced MCF-7 cell proliferation was interfered with testosterone (an aromatase substrate) and exogenously provided E2, it is suggested that (1) the growth stimulatory effects of Δ9-THC are mediated by the product(s) of COX-2 except for PGE2, (2) the action of Δ9-THC is modulated by E2, and (3) COX-2 and aromatase are individually engaged in the proliferation of MCF-7 cells induced by Δ9-THC.

  9. Randomized controlled trial of toremifene 120 mg compared with exemestane 25 mg after prior treatment with a non-steroidal aromatase inhibitor in postmenopausal women with hormone receptor-positive metastatic breast cancer

    International Nuclear Information System (INIS)

    After the failure of a non-steroidal aromatase inhibitor (nsAI) for postmenopausal patients with metastatic breast cancer (mBC), it is unclear which of various kinds of endocrine therapy is the most appropriate. A randomized controlled trial was performed to compare the efficacy and safety of daily toremifene 120 mg (TOR120), a selective estrogen receptor modulator, and exemestane 25 mg (EXE), a steroidal aromatase inhibitor. The primary end point was the clinical benefit rate (CBR). The secondary end points were objective response rate (ORR), progression-free survival (PFS), overall survival (OS) and toxicity. Initially, a total of 91 women was registered in the study and randomly assigned to either TOR120 (n = 46) or EXE (n = 45) from October 2008 to November 2011. Three of the 46 patients in the TOR120 arm were not received treatment, 2 patients having withdrawn from the trial by their preference and one having been dropped due to administration of another SERM. When analyzed after a median observation period of 16.9 months, the intention-to-treat analysis showed that there were no statistical difference between TOR120 (N = 46) and EXE (n = 45) in terms of CBR (41.3% vs. 26.7%; P = 0.14), ORR (10.8% vs. 2.2%; P = 0.083), and OS (Hazard ratio, 0.60; P = 0.22). The PFS of TOR120 was longer than that of EXE, the difference being statistically significant (Hazard ratio, 0.61, P = 0.045). The results in treatment-received cohort (N = 88) were similar to those in ITT cohort. Both treatments were well-tolerated with no severe adverse events, although the treatment of 3 of 43 women administered TOR120 was stopped after a few days because of nausea, general fatigue, hot flush and night sweating. TOR120, as a subsequent endocrine therapy for mBC patients who failed non-steroidal AI treatment, could potentially be more beneficial than EXE. https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr.cgi?function

  10. Inhibition of rainbow trout (Oncorhynchus mykiss) P450 aromatase activities in brain and ovarian microsomes by various environmental substances.

    Science.gov (United States)

    Hinfray, Nathalie; Porcher, Jean-Marc; Brion, François

    2006-11-01

    Aromatase, a key steroidogenic enzyme that catalyses the conversion of androgens to estrogens, represent a target for endocrine disrupting chemicals. However, little is known about the effect of pollutants on aromatase enzymes in fish. In this study, we first optimized a rainbow trout (Oncorhynchus mykiss) microsomal aromatase assay to measure the effects of 43 substances belonging to diverse chemical classes (steroidal and non steroidal aromatase inhibitors, pesticides, heavy metals, organotin compounds, dioxins, polycyclic aromatic hydrocarbons) on brain and ovarian aromatase activities in vitro. Our results showed that 12 compounds were able to inhibit brain and ovarian aromatase activities in a dose-dependent manner with IC50 values ranging from the low nM to the high microM range depending on the substance: steroidal and non steroidal inhibitors of aromatase (4-hydroxyandrostenedione, androstatrienedione, aminogluthethimide), imidazole fungicides (clotrimazole, imazalil, prochloraz), triazole fungicides (difenoconazole, fenbuconazole, propiconazole, triadimenol), the pyrimidine fungicide fenarimol and methylmercury. Overall, this study demonstrates that rainbow trout brain and ovarian microsomal aromatase assay is suitable for evaluating potential aromatase inhibitors in vitro notably with respect to environmental screening. The results highlight that methylmercury and some pesticides that are currently used throughout the world, have the potential to interfere with the biosynthesis of endogenous estrogens in fish. PMID:17081805

  11. Metformin Reverses Development of Pulmonary Hypertension via Aromatase Inhibition.

    Science.gov (United States)

    Dean, Afshan; Nilsen, Margaret; Loughlin, Lynn; Salt, Ian P; MacLean, Margaret R

    2016-08-01

    Females are more susceptible to pulmonary arterial hypertension than males, although the reasons remain unclear. The hypoglycemic drug, metformin, is reported to have multiple actions, including the inhibition of aromatase and stimulation of AMP-activated protein kinase. Inhibition of aromatase using anastrazole is protective in experimental pulmonary hypertension but whether metformin attenuates pulmonary hypertension through this mechanism remains unknown. We investigated whether metformin affected aromatase activity and if it could reduce the development of pulmonary hypertension in the sugen 5416/hypoxic rat model. We also investigated its influence on proliferation in human pulmonary arterial smooth muscle cells. Metformin reversed right ventricular systolic pressure, right ventricular hypertrophy, and decreased pulmonary vascular remodeling in the rat. Furthermore, metformin increased rat lung AMP-activated protein kinase signaling, decreased lung and circulating estrogen levels, levels of aromatase, the estrogen metabolizing enzyme; cytochrome P450 1B1 and its transcription factor; the aryl hydrocarbon receptor. In human pulmonary arterial smooth muscle cells, metformin decreased proliferation and decreased estrogen synthesis by decreasing aromatase activity through the PII promoter site of Cyp19a1 Thus, we report for the first time that metformin can reverse pulmonary hypertension through inhibition of aromatase and estrogen synthesis in a manner likely to be mediated by AMP-activated protein kinase. PMID:27296990

  12. Nicotine Blocks Brain Estrogen Synthase (Aromatase): In Vivo Positron Emission Tomography Studies in Female Baboons

    International Nuclear Information System (INIS)

    Cigarette smoking and nicotine have complex effects on human physiology and behavior, including some effects similar to those elicited by inhibition of aromatase, the last enzyme in estrogen biosynthesis. We report the first in vivo primate study to determine whether there is a direct effect of nicotine administration on brain aromatase. Brain aromatase availability was examined with positron emission tomography and the selective aromatase inhibitor (11C)vorozole in six baboons before and after exposure to IV nicotine at .015 and .03 mg/kg. Nicotine administration produced significant, dose-dependent reductions in (11C)vorozole binding. The amygdala and preoptic area showed the largest reductions. Plasma levels of nicotine and its major metabolite cotinine were similar to those found in cigarette smokers. Nicotine interacts in vivo with primate brain aromatase in regions involved in mood, aggression, and sexual behavior.

  13. Nicotine Blocks Brain Estrogen Synthase (Aromatase): In Vivo Positron Emission Tomography Studies in Female Baboons

    Energy Technology Data Exchange (ETDEWEB)

    Biegon, A.; Biegon, A.; Kim, S.-W.; Logan, J.; Hooker, J.M.; Muench, L.; Fowler, J.S.

    2010-01-12

    Cigarette smoking and nicotine have complex effects on human physiology and behavior, including some effects similar to those elicited by inhibition of aromatase, the last enzyme in estrogen biosynthesis. We report the first in vivo primate study to determine whether there is a direct effect of nicotine administration on brain aromatase. Brain aromatase availability was examined with positron emission tomography and the selective aromatase inhibitor [{sup 11}C]vorozole in six baboons before and after exposure to IV nicotine at .015 and .03 mg/kg. Nicotine administration produced significant, dose-dependent reductions in [{sup 11}C]vorozole binding. The amygdala and preoptic area showed the largest reductions. Plasma levels of nicotine and its major metabolite cotinine were similar to those found in cigarette smokers. Nicotine interacts in vivo with primate brain aromatase in regions involved in mood, aggression, and sexual behavior.

  14. Imaging of aromatase distribution in rat and rhesus monkey brains with [{sup 11}C]vorozole

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Kayo [Division of Pharmacology, Department of Neuroscience, Uppsala University, Uppsala SE-75124 (Sweden); Uppsala Imanet, Uppsala SE-75109 (Sweden)]. E-mail: kayo.takahashi@uppsala.imanet.se; Bergstroem, Mats [Uppsala Imanet, Uppsala SE-75109 (Sweden); Department of Pharmaceutical Biosciences, Uppsala University, Uppsala SE-75124 (Sweden); Fraendberg, Pernilla [Uppsala Imanet, Uppsala SE-75109 (Sweden); Vesstroem, Eva-Lotta [Uppsala Imanet, Uppsala SE-75109 (Sweden); Watanabe, Yasuyoshi [Department of Physiology, Osaka City University Graduate School of Medicine, Osaka 545-8585 (Japan); Langstroem, Bengt [Uppsala Imanet, Uppsala SE-75109 (Sweden)

    2006-07-15

    Aromatase is an enzyme that converts androgens to estrogens and may play a role in mood and mental status. The aim of this study was to demonstrate that brain aromatase distribution could be evaluated with a novel positron emission tomography (PET) tracer [{sup 11}C]vorozole. Vorozole is a nonsteroidal aromatase inhibitor that reversibly binds to the heme domain of aromatase. In vitro experiments in rat brain, using frozen section autoradiography, illustrated specific binding in the medial amygdala (MA), the bed nucleus of stria terminalis (BST) and the preoptic area (POA) of male rat brain. Specific binding in female rat brain was found in the MA and the BST; however, the signals were lower than those of males. The K {sub d} of [{sup 11}C]vorozole binding to aromatase in MA was determined to be 0.60{+-}0.06 nM by Scatchard plot analysis using homogenates. An in vivo PET study in female rhesus monkey brain demonstrated the uptake of [{sup 11}C]vorozole in the amygdala, where the uptake was blocked by the presence of excess amounts of unlabeled vorozole. Thus, this tracer has a high affinity for brain aromatase and could have a potential for in vivo aromatase imaging. This technique might enable the investigation of human brain aromatase in healthy and diseased persons.

  15. Imaging of aromatase distribution in rat and rhesus monkey brains with [11C]vorozole

    International Nuclear Information System (INIS)

    Aromatase is an enzyme that converts androgens to estrogens and may play a role in mood and mental status. The aim of this study was to demonstrate that brain aromatase distribution could be evaluated with a novel positron emission tomography (PET) tracer [11C]vorozole. Vorozole is a nonsteroidal aromatase inhibitor that reversibly binds to the heme domain of aromatase. In vitro experiments in rat brain, using frozen section autoradiography, illustrated specific binding in the medial amygdala (MA), the bed nucleus of stria terminalis (BST) and the preoptic area (POA) of male rat brain. Specific binding in female rat brain was found in the MA and the BST; however, the signals were lower than those of males. The K d of [11C]vorozole binding to aromatase in MA was determined to be 0.60±0.06 nM by Scatchard plot analysis using homogenates. An in vivo PET study in female rhesus monkey brain demonstrated the uptake of [11C]vorozole in the amygdala, where the uptake was blocked by the presence of excess amounts of unlabeled vorozole. Thus, this tracer has a high affinity for brain aromatase and could have a potential for in vivo aromatase imaging. This technique might enable the investigation of human brain aromatase in healthy and diseased persons

  16. Genetics Home Reference: aromatase excess syndrome

    Science.gov (United States)

    ... males, the increased aromatase and subsequent conversion of androgens to estrogen are responsible for the gynecomastia and limited bone growth characteristic of aromatase excess syndrome . Increased estrogen in females can cause symptoms ...

  17. Aromatase Expression in the Hippocampus of AD Patients and 5xFAD Mice

    Science.gov (United States)

    Prange-Kiel, Janine; Dudzinski, Danuta A.; Pröls, Felicitas; Glatzel, Markus; Matschke, Jakob; Rune, Gabriele M.

    2016-01-01

    Numerous studies show that 17β-estradiol (E2) protects against Alzheimer's disease (AD) induced neurodegeneration. The E2-synthesizing enzyme aromatase is expressed in healthy hippocampi, but although the hippocampus is severely affected in AD, little is known about the expression of hippocampal aromatase in AD. To better understand the role of hippocampal aromatase in AD, we studied its expression in postmortem material from patients with AD and in a mouse model for AD (5xFAD mice). In human hippocampi, aromatase-immunoreactivity was observed in the vast majority of principal neurons and signal quantification revealed higher expression of aromatase protein in AD patients compared to age- and sex-matched controls. The tissue-specific first exons of aromatase I.f, PII, I.3, and I.6 were detected in hippocampi of controls and AD patients by RT-PCR. In contrast, 3-month-old, female 5xFAD mice showed lower expression of aromatase mRNA and protein (measured by qRT-PCR and semiquantitative immunohistochemistry) than WT controls; no such differences were observed in male mice. Our findings stress the importance of hippocampal aromatase expression in neurodegenerative diseases. PMID:27298742

  18. The effects of diabetes on placental aromatase activity.

    Science.gov (United States)

    McRobie, D J; Korzekwa, K R; Glover, D D; Tracy, T S

    1997-01-01

    Diabetes complicates 2-3% of all pregnancies and is associated with an increase in both perinatal morbidity and mortality, though reasons for these adverse outcomes are unknown. Estrogen biosynthesis is a critical factor during pregnancy and is carried out in the placenta via aromatase (cytochrome P450 19A1), which catalyzes the conversion of C-19 androgens to C-18 estrogens. Previous studies have shown that hormones such as insulin-like growth factors and insulin regulate aromatase activity when studied in vitro. Interestingly, levels of these hormones are altered in patients with diabetes. Thus, we hypothesized that the presence of maternal diabetes may alter placental aromatase activity and thus estrogen biosynthesis, possibly serving as one factor in the adverse outcomes of babies born to mothers with diabetes. To this end, we measured the production of 19-hydroxyandrostenedione, 19-oxoadrostenedione and estrone in 30 placental tissues from diabetic patients, using [7-3H]androst-4-ene-3,17-dione as a model substrate for aromatase (P450 19A1). A statistical difference was detected in the percentage of 19-oxoandrostenedione formed between the overt and control groups (P < 0.05). Additionally, NADPH P450-reductase levels were measured in these same tissues to determine whether alterations in this enzyme necessary for aromatase activity could be affected by diabetes. No differences in reductase levels were detected among the patient groups. However, a statistical correlation was found between NADPH P450-reductase activity and the formation velocities of all three estrogen products (P < 0.05). Thus, it appears that the presence of diabetes does not affect placental aromatase activity. PMID:9449216

  19. Dual protonophore-chitinase inhibitors dramatically affect O. volvulus molting.

    Science.gov (United States)

    Gooyit, Major; Tricoche, Nancy; Lustigman, Sara; Janda, Kim D

    2014-07-10

    The L3-stage-specific chitinase OvCHT1 has been implicated in the development of Onchocerca volvulus, the causative agent of onchocerciasis. Closantel, a known anthelmintic drug, was previously discovered as a potent and specific OvCHT1 inhibitor. As closantel is also a known protonophore, we performed a simple scaffold modulation to map out the structural features that are relevant for its individual or dual biochemical roles. Furthermore, we present that either OvCHT1 inhibition or protonophoric activity was capable of affecting O. volvulus L3 molting and that the presence of both activities in a single molecule yielded more potent inhibition of the nematode's developmental process. PMID:24918716

  20. JAK2 inhibitors do not affect stem cells present in the spleens of patients with myelofibrosis

    OpenAIRE

    Wang, Xiaoli; Ye, Fei; Tripodi, Joseph; Hu, Cing Siang; Qiu, Jiajing; Najfeld, Vesna; Novak, Jesse; Li, Yan; Rampal, Raajit; Hoffman, Ronald

    2014-01-01

    JAK2 inhibitors affect more mature MF progenitors, but spare disease-initiating stem cells.Reduction in spleen size achieved with JAK2 inhibitor therapy in MF can be attributed to depletion of a subpopulation of MF progenitors.

  1. Organizing effects of sex steroids on brain aromatase activity in quail.

    Directory of Open Access Journals (Sweden)

    Charlotte A Cornil

    Full Text Available Preoptic/hypothalamic aromatase activity (AA is sexually differentiated in birds and mammals but the mechanisms controlling this sex difference remain unclear. We determined here (1 brain sites where AA is sexually differentiated and (2 whether this sex difference results from organizing effects of estrogens during ontogeny or activating effects of testosterone in adulthood. In the first experiment we measured AA in brain regions micropunched in adult male and female Japanese quail utilizing the novel strategy of basing the microdissections on the distribution of aromatase-immunoreactive cells. The largest sex difference was found in the medial bed nucleus of the stria terminalis (mBST followed by the medial preoptic nucleus (POM and the tuberal hypothalamic region. A second experiment tested the effect of embryonic treatments known to sex-reverse male copulatory behavior (i.e., estradiol benzoate [EB] or the aromatase inhibitor, Vorozole on brain AA in gonadectomized adult males and females chronically treated as adults with testosterone. Embryonic EB demasculinized male copulatory behavior, while vorozole blocked demasculinization of behavior in females as previously demonstrated in birds. Interestingly, these treatments did not affect a measure of appetitive sexual behavior. In parallel, embryonic vorozole increased, while EB decreased AA in pooled POM and mBST, but the same effect was observed in both sexes. Together, these data indicate that the early action of estrogens demasculinizes AA. However, this organizational action of estrogens on AA does not explain the behavioral sex difference in copulatory behavior since AA is similar in testosterone-treated males and females that were or were not exposed to embryonic treatments with estrogens.

  2. Effect of ultra-low-dose estriol and lactobacilli vaginal tablets (Gynoflor®) on inflammatory and infectious markers of the vaginal ecosystem in postmenopausal women with breast cancer on aromatase inhibitors.

    Science.gov (United States)

    Donders, G; Bellen, G; Neven, P; Grob, P; Prasauskas, V; Buchholz, S; Ortmann, O

    2015-10-01

    This study was a detailed microscopic analysis of the changes of vaginal microflora characteristics after application of 0.03 mg estriol-lactobacilli combination on the vaginal ecosystem in postmenopausal breast cancer (BC) survivors on aromatase inhibitors (AI) with severe atrophic vaginitis. A total of 16 BC women on AI applied daily one vaginal tablet of Gynoflor® for 28 days followed by a maintenance therapy of three tablets weekly for 8 weeks. During four follow up visits a smear from the upper lateral vaginal wall was analysed by phase contrast microscopy at 400 times magnification in order to classify the lactobacillary grades(LBG), bacterial vaginosis (BV), aerobic vaginitis (AV), vulvovaginal candidosis (VVC), proportional number of leukocytes and evidence of parabasal cells and epitheliolysis. LBG improved from 81% LBG-III at entry to 88% LBG-I&IIa after 2 weeks of initial therapy, which further improved upon follow up (p treatment (p < 0.01). While at entry most patients had moderate or severe AV, after maintenance therapy no patient except one had AV. The number of leukocytes dropped dramatically from a score of 1.78 ± 0.70 to 1.06 ± 0.25 which was consistent till the end of the study (p < 0.01). Parabasal cells dropped from a score of 3.4 ± 0.64 at entry to 1.3 ± 0.60 at the final visit (p trend < 0.01). Starting from a low rate of Candida colonisation of 2/14 (14%), a sudden rise to 7/16 (44%) occurred after 2 weeks, to return back to base levels at subsequent visits. The vaginal use of ultra-low dose estriol and lactobacilli results in rapid and enduring improvement of all markers of the vaginal microflora and epithelial vaginal cell quality in women with breast cancer on AI with dyspareunia. Candida may develop soon after its use, but rapidly disappears again upon their prolonged use. Due to its excellent safety profiles and clinical efficacy we recommend this product as first choice in women on AI with severe dyspareunia. PMID:26223323

  3. Genetics Home Reference: aromatase deficiency

    Science.gov (United States)

    ... regulating bone growth and blood sugar levels. During fetal development, aromatase converts androgens to estrogens in the placenta, ... link between the mother's blood supply and the fetus. This conversion in the ... sexual development in female fetuses. After birth, the conversion of ...

  4. Aromatase inhibitors in stimulated IVF cycles

    DEFF Research Database (Denmark)

    Papanikolaou, Evangelos G; Polyzos, Nikolaos P; Al Humaidan, Peter Samir Heskjær;

    2011-01-01

    intriguing to test in the future how it may perform when used in GnRH agonist cycles. Finally administration of letrozole during luteal phase in IVF cycles offers another treatment modality for patients at high risk for OHSS taking into account that it drastically reduces estradiol levels....... available regarding their efficacy in IVF stimulated cycles. Current available evidence support that letrozole may have a promising role in stimulated IVF cycles, either when administered during the follicular phase for ovarian stimulation. Especially for women with poor ovarian response, letrozole appears...... to have the potential to increase clinical pregnancy rates when combined with gonadotropins, whereas at the same time reduces the total gonadotropin dose required for ovarian stimulation. However, given that in all of the trials letrozole has been administered in GnRH antagonist cycles, it is...

  5. Aromatase in human liver and its diseases

    International Nuclear Information System (INIS)

    Estrogens play important roles in the cell proliferation and invasion of estrogen-dependent human neoplasms. Aromatase overexpression has been also reported in hepatitis and hepatocellular carcinoma (HCC) compared with normal liver but its details in these hepatic disorders have remained unclear. Therefore, in this study, we first immunolocalized aromatase using immunohistochemistry in patients with liver cirrhosis, steatosis, hepatitis, HCC, and metastasis liver carcinoma (MLC) in order to study the detailed status of intrahepatic aromatase. Aromatase immunoreactivity was predominantly detected in nonneoplastic hepatocytes around tumor cells. We then evaluated the effects of an interaction between hepatocytes and carcinoma cells upon aromatase mRNA expression, using HepG2 as a substitute model of hepatocytes by coculture systems. Aromatase mRNA levels in HepG2 were significantly increased by coculture with all carcinoma cell lines examined. We also evaluated alternative splicing of aromatase exon 1 but the same splicing variant was used in HepG2 cells regardless of carcinoma cell lines employed in the coculture system. These findings obtained in HepG2 indicated that carcinoma cells, whether metastatic or primary, induced aromatase expression in adjacent normal hepatocytes possibly through the soluble aromatase inducible factors in human hepatic microenvironments

  6. Peripubertal aromatase inhibition in male rats has adverse long-term effects on bone strength and growth and induces prostatic hyperplasia.

    Science.gov (United States)

    Bajpai, Anurag; Simm, Peter J; McPherson, Stephen J; Russo, Vincenzo C; Azar, Walid J; Wark, John D; Risbridger, Gail P; Werther, George A

    2010-10-01

    Aromatase inhibitors have been increasingly used in boys with growth retardation to prolong the duration of growth and increase final height. Multiple important roles of oestrogen in males point to potential adverse effects of this strategy. Although the deleterious effects of aromatase deficiency in early childhood and adulthood are well documented, there is limited information about the potential long-term adverse effects of peripubertal aromatase inhibition. To address this issue, we evaluated short-term and long-term effects of peripubertal aromatase inhibition in an animal model. Peripubertal male Wistar rats were treated with aromatase inhibitor letrozole or placebo and followed until adulthood. Letrozole treatment caused sustained reduction in bone strength and alteration in skeletal geometry, lowering of IGF1 levels, inhibition of growth resulting in significantly lower weight and length of treated animals and development of focal prostatic hyperplasia. Our observation of adverse long-term effects after peripubertal male rats were exposed to aromatase inhibitors highlights the need for further characterisation of long-term adverse effects of aromatase inhibitors in peripubertal boys before further widespread use is accepted. Furthermore, this suggests the need to develop more selective oestrogen inhibition strategies in order to inhibit oestrogen action on the growth plate, while beneficial effects in other tissues are preserved. PMID:20675302

  7. Celecoxib increases miR-222 while deterring aromatase-expressing breast tumor growth in mice

    International Nuclear Information System (INIS)

    Breast cancer is one of the most deadly diseases in women. Inhibiting the synthesis of estrogen is effective in treating patients with estrogen-responsive breast cancer. Previous studies have demonstrated that use of cyclooxygenase (COX) inhibitors is associated with reduced breast cancer risk. In the present study, we employed an established mouse model for postmenopausal breast cancer to evaluate the potential mechanisms of the COX-2 inhibitor celecoxib. Aromatase-expressing MCF-7 cells were transplanted into ovariectomized athymic mice. The animals were given celecoxib at 1500 ppm or aspirin at 200 ppm by oral administration with androstenedione injection. Our results showed that both COX inhibitors could suppress the cancer xenograft growth without changing the plasma estrogen level. Protein expression of ERα, COX-2, Cyclin A, and Bcl-xL were reduced in celecoxib-treated tumor samples, whereas only Bcl-xL expression was suppressed in those treated with aspirin. Among the breast cancer-related miRNAs, miR-222 expression was elevated in samples treated with celecoxib. Further studies in culture cells verified that the increase in miR-222 expression might contribute to ERα downregulation but not the growth deterrence of cells. Overall, this study suggested that both celecoxib and aspirin could prevent breast cancer growth by regulating proteins in the cell cycle and apoptosis without blocking estrogen synthesis. Besides, celecoxib might affect miR expression in an undesirable fashion

  8. Celecoxib increases miR-222 while deterring aromatase-expressing breast tumor growth in mice

    OpenAIRE

    Wong, Tsz Yan; Li, Fengjuan; Lin, Shu-mei; Franky L Chan; Chen, Shiuan; Leung, Lai K.

    2014-01-01

    Background Breast cancer is one of the most deadly diseases in women. Inhibiting the synthesis of estrogen is effective in treating patients with estrogen-responsive breast cancer. Previous studies have demonstrated that use of cyclooxygenase (COX) inhibitors is associated with reduced breast cancer risk. Methods In the present study, we employed an established mouse model for postmenopausal breast cancer to evaluate the potential mechanisms of the COX-2 inhibitor celecoxib. Aromatase-express...

  9. Ginkgo biloba extract EGb 761-mediated inhibition of aromatase for the treatment of hormone-dependent breast cancer.

    Science.gov (United States)

    Park, Yong Joo; Ahn, Hui Yeon; Kim, Ha Ryong; Chung, Kyu Hyuck; Oh, Seung Min

    2016-01-01

    Ginkgo biloba has been used in herbal medicines for thousands of years. Although a standard G. biloba extract, EGb 761 has been used to improve cognition in breast cancer patients, its effects on breast cancer are unknown. Therefore, we investigated the antitumorigenic effects of EGb 761 using an in vitro cell model and an in vivo xenograft model. EGb 761 significantly inhibited aromatase activity in aromatase over-expressing MCF-7 cells (MCF-7 AROM). In addition, EGb 761 exposure reduced cytochrome p450 aromatase (CYP19) mRNA and protein expression; CYP19 promoter I.3 and PII expression particularly decreased. These inhibitory effects on aromatase were accompanied by reduced 17β-estradiol levels in MCF-7 AROM cells. For elucidating antitumorigenic effects, MCF-7 AROM cells were implanted in BALB/c nude mice prior to oral EGb 761 treatment for 3 weeks. EGb 761 reduced the tumor size and significantly reduced tumor CYP19 mRNA expression. Taken together, our results indicated that EGb 761 inhibited aromatase and exerted antitumor effects on breast cancer cells both in vitro and in vivo. These findings suggest that EGb761 may be a useful aromatase inhibitor for the treatment for estrogen-sensitive breast cancer. PMID:26706698

  10. Effects of transferrin on aromatase activity in porcine granulosa cells in vitro.

    Directory of Open Access Journals (Sweden)

    Małgorzata Duda

    2009-01-01

    Full Text Available Proliferating cells have an absolute requirement for iron, which is delivered by transferrin with subsequent intracellular transport via the transferrin receptor. Recent studies have reported that transferrin plays a crucial role in the local regulation of ovarian function, apart from its iron-binding characteristic. Therefore, the present study was undertaken to explore the possible role of transferrin in porcine granulosa cells function by examining its influence on aromatase activity, the most important indicator of follicular cell differentiation. In the first series of studies, pig granulosa cells isolated from small, immature follicles were cultured in the presence of transferrin alone (10 microg/ml or 100 microg/ml or with the addition of FSH (100ng/ml. The second series of studies was undertaken to determine transferrin-stimulated granulosa cells ability to aromatize exogenous testosterone (1x10(-7M. One hour after the establishment of cultures an aromatase inhibitor CGS16949A was added to test its influence on estradiol production. After 48 hours, cultures were terminated and cells were processed for immunocytochemical staining of aromatase. Media were frozen for further estradiol level analysis. Positive immunostaining for aromatase was found in all granulosa cell cultures. The intensity of immunostaining was always stronger in cultures supplemented with FSH whereas the addition of transferrin had no effect. Granulosa cells in vitro synthesized the highest amount of estradiol after the addition of FSH and exogenous testosterone as measured radioimmunologically. Concomitant treatment with FSH and transferrin caused an inhibition of FSH-stimulated aromatase activity. The production of estradiol also declined in the presence of FSH, testosterone and transferrin. This study demonstrates that transferrin had a dose-dependent inhibitory effect on FSH-stimulated aromatase activity, which was confirmed by radioimmunoassay. Our results indicate

  11. Molecular simulations of aromatase reveal new insights into the mechanism of ligand binding.

    Science.gov (United States)

    Park, Jiho; Czapla, Luke; Amaro, Rommie E

    2013-08-26

    CYP19A1, also known as aromatase or estrogen synthetase, is the rate-limiting enzyme in the biosynthesis of estrogens from their corresponding androgens. Several clinically used breast cancer therapies target aromatase. In this work, explicitly solvated all-atom molecular dynamics simulations of aromatase with a model of the lipid bilayer and the transmembrane helix are performed. The dynamics of aromatase and the role of titration of an important amino acid residue involved in aromatization of androgens are investigated via two 250-ns long simulations. One simulation treats the protonated form of the catalytic aspartate 309, which appears more consistent with crystallographic data for the active site, while the simulation of the deprotonated form shows some notable conformational shifts. Ensemble-based computational solvent mapping experiments indicate possible novel druggable binding sites that could be utilized by next-generation inhibitors. In addition, the effects of protonation on the ligand positioning and channel dynamics are investigated using geometrical models that estimate the opening width of critical channels. Significant differences in channel dynamics between the protonated and deprotonated trajectories are exhibited, suggesting that the mechanism for substrate and product entry and the aromatization process may be coupled to a "locking" mechanism and channel opening. Our results may be particularly relevant in the design of novel drugs, which may be useful therapeutic treatments of cancers such as those of the breast and prostate. PMID:23927370

  12. Sex differences in brain aromatase activity: genomic and non-genomic controls

    Directory of Open Access Journals (Sweden)

    Jacques eBalthazart

    2011-09-01

    Full Text Available Aromatization of testosterone into estradiol in the preoptic area plays a critical role in the activation of male copulation in quail and in many other vertebrate species. Aromatase expression in quail and in other birds is higher than in rodents and other mammals, which has facilitated the study of the controls and functions of this enzyme. Over relatively long time periods (days to months, brain aromatase activity and transcription are markedly (4-6 fold increased by genomic actions of sex steroids. Initial work indicated that the preoptic aromatase activity is higher in males than in females and it was hypothesized that this differential production of estrogen could be a critical factor responsible for the lack of behavioral activation in females. Subsequent studies revealed, however, that this enzymatic sex difference might contribute but is not sufficient to explain the sex difference in behavior. Studies of aromatase activity, immunoreactivity and mRNA concentrations revealed that sex differences observed when measuring enzymatic activity are not necessarily observed when one measures mRNA concentrations. Discrepancies potentially reflect post-translational controls of the enzymatic activity. Aromatase activity in quail brain homogenates is rapidly inhibited by phosphorylation processes. Similar rapid inhibitions occur in hypothalamic explants maintained in vitro and exposed to agents affecting intracellular calcium concentrations or to glutamate agonists. Rapid changes in aromatase activity have also been observed in vivo following sexual interactions or exposure to short-term restraint stress and these rapid changes in estrogen production modulate expression of male sexual behaviors. These data suggest that brain estrogens display most if not all characteristics of neuromodulators if not neurotransmitters. Many questions remain however concerning the mechanisms controlling these rapid changes in estrogen production and their behavioral

  13. Aromatase imaging with [N-methyl-C-11]vorozole PET in healthy men and women

    International Nuclear Information System (INIS)

    Aromatase, the last and obligatory enzyme catalyzing estrogen biosynthesis from androgenic precursors, can be labeled in vivo with (11)C-vorozole. Aromatase inhibitors are widely used in breast cancer and other endocrine conditions. The present study aims to provide baseline information defining aromatase distribution in healthy men and women, against which its perturbation in pathological situations can be studied. Methods: (11)C-vorozole (111-296 MBq/subject) was injected I.V in 13 men and 20 women (age range 23 to 67). PET data were acquired over a 90 minute period. Each subject had 4 scans, 2/day separated by 2-6 weeks, including brain and torso or pelvis scans. Young women were scanned at 2 discrete phases of the menstrual cycle (midcycle and late luteal). Men and postmenopausal women were also scanned following pretreatment with a clinical dose of the aromatase inhibitor letrozole.Time activity curves were obtained and standard uptake values (SUV) calculated for major organs including brain, heart, lungs, liver, kidneys, spleen, muscle, bone and male and female reproductive organs (penis, testes, uterus, ovaries). Organ and whole body radiation exposures were calculated using Olinda software. Results: Liver uptake was higher than all other organs, but was not blocked by pretreatment with letrozole. Mean SUVs in men were higher than in women, and brain uptake was blocked by letrozole. Male brain SUVs were also higher than all other organs (ranging from 0.48±0.05 in lungs to 1.5±0.13 in kidneys). Mean ovarian SUVs (3.08±0.7) were comparable to brain levels and higher than all other organs. Furthermore, ovarian SUVs In young women around the time of ovulation (midcycle) were significantly higher than those measured in the late luteal phase, while aging and cigarette smoking reduced (11)C-vorozole uptake. Conclusions: PET with (11)C-vorozole is useful for assessing physiological changes in estrogen synthesis capacity in the human body. Baseline levels in

  14. Investigation of aromatase inhibitory activity of metal complexes of 8-hydroxyquinoline and uracil derivatives

    Directory of Open Access Journals (Sweden)

    Prachayasittikul V

    2014-08-01

    Full Text Available Veda Prachayasittikul,1 Ratchanok Pingaew,2 Chanin Nantasenamat,3 Supaluk Prachayasittikul,3 Somsak Ruchirawat,4,5 Virapong Prachayasittikul1 1Department of Clinical Microbiology and Applied Technology, Faculty of Medical Technology, Mahidol University, Bangkok, Thailand; 2Department of Chemistry, Faculty of Science, Srinakharinwirot University, Bangkok, Thailand; 3Center of Data Mining and Biomedical Informatics, Faculty of Medical Technology, Mahidol University, Bangkok, Thailand; 4Laboratory of Medicinal Chemistry, Chulabhorn Research Institute, 5Chulabhorn Graduate Institute, Bangkok, Thailand Purpose: Estrogens play important roles in the pathogenesis and progression of breast cancer as well as estrogen-related diseases. Aromatase is a key enzyme in the rate-limiting step of estrogen production, in which its inhibition is one strategy for controlling estrogen levels to improve prognosis of estrogen-related cancers and diseases. Herein, a series of metal (Mn, Cu, and Ni complexes of 8-hydroxyquinoline (8HQ and uracil derivatives (4–9 were investigated for their aromatase inhibitory and cytotoxic activities. Methods: The aromatase inhibition assay was performed according to a Gentest™ kit using CYP19 enzyme, wherein ketoconazole and letrozole were used as reference drugs. The cytotoxicity was tested on normal embryonic lung cells (MRC-5 using 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT assay. Results: Only Cu complexes (6 and 9 exhibited aromatase inhibitory effect with IC50 0.30 and 1.7 µM, respectively. Cytotoxicity test against MRC-5 cells showed that Mn and Cu complexes (5 and 6, as well as free ligand 8HQ, exhibited activity with IC50 range 0.74–6.27 µM. Conclusion: Cu complexes (6 and 9 were found to act as a novel class of aromatase inhibitor. Our findings suggest that these 8HQ–Cu–uracil complexes are promising agents that could be potentially developed as a selective anticancer agent for breast cancer

  15. Cytotoxic effects and aromatase inhibition by xenobiotic endocrine disrupters alone and in combination

    International Nuclear Information System (INIS)

    Xenobiotics may cause long-term adverse effects in humans, especially at the embryonic level, raising questions about their levels of exposure, combined effects, and crucial endpoints. We are interested in the possible interactions between xenobiotic endocrine disrupters, cellular viability and androgen metabolism. Accordingly, we tested aroclor 1254 (A1254), atrazine (AZ), o,p'-DDT, vinclozolin (VZ), p,p'-DDE, bisphenol A (BPA), chlordecone (CD), nonylphenol (NP), tributylin oxide (TBTO), and diethylstilbestrol (DES) for cellular toxicity against human embryonic 293 cells, and activity against cellular aromatase, but also on placental microsomes and on the purified equine enzyme. Cellular viability was affected in 24 h by all the xenobiotics with a threshold at 50 μM (except for TBTO and DES, 10 μM threshold), and aromatase was inhibited at non-toxic doses. In combination synergism was observed reducing the threshold values of toxicity to 4-10 μM, and aromatase activity by 50% in some cases. In placental microsomes the most active xenobiotics rapidly inhibited microsomal aromatase in a manner independent of NADPH metabolism. Prolonged exposures to low doses in cells generally amplified by 50 times aromatase inhibition. These xenobiotics may act by inhibition of the active site or by allosteric effects on the enzyme. Bioaccumulation is a feature of some xenobiotics, especially chlordecone, DDT and DDE, and low level chronic exposures can also affect cell signaling mechanisms. This new information about the mechanism of action of these xenobiotics will assist in improved molecular design with a view to providing safer compounds for use in the (human) environment

  16. Developmental regulation of aromatase activity in the rat hypothalamus

    International Nuclear Information System (INIS)

    The brain of all mammalian species studied thus far contain an enzymatic activity (aromatase) that catalyzes the conversion of androgens to estrogens. The activity is highest during prenatal development and contributes to the establishment of sex differences which determine adult gonadotropin secretion patterns and reproductive behavior. The studies presented in this dissertation represent a systematic effort to elucidate the mechanism(s) that control the initiation of and contribute to maintaining rat hypothalamic aromatase activity during pre- and postnatal development. Aromatase enzyme activity was measured by the 3H2O release assay or by traditional estrogen product isolation. Brain aromatase mRNA was detected by hybridization to a cDNA encoding rat aromatase cytochrome P-450. In both males and females the time of puberty was associated with a decline in hypothalamic aromatase activity. This decline may represent a factor underlying the peri-pubertal decrease in the sensitivity to gonadal steroid feedback that accompanies completion of puberty. The results also indicate that androgens regulate brain aromatase levels during both the prepubertal and peri-pubertal stages of sexual development and that this regulation is transiently lost in young adults. Utilizing a hypothalamic organotypic culture system, aromatase activity in vitro was maintained for as long as two days. The results of studies of a variety of hormonal and metabolic regulators suggest that prenatal aromatase activity is regulated by factor(s) that function independently from the classical cyclic AMP and protein kinase C trans-membrane signaling pathways

  17. Mini Screening of Kinase Inhibitors Affecting Period-length of Mammalian Cellular Circadian Clock

    International Nuclear Information System (INIS)

    In mammalian circadian rhythms, the transcriptional-translational feedback loop (TTFL) consisting of a set of clock genes is believed to elicit the circadian clock oscillation. The TTFL model explains that the accumulation and degradation of mPER and mCRY proteins control the period-length (tau) of the circadian clock. Although recent studies revealed that the Casein Kinase Iεδ (CKIεδ) regurates the phosphorylation of mPER proteins and the circadian period-length, other kinases are also likely to contribute the phosphorylation of mPER. Here, we performed small scale screening using 84 chemical compounds known as kinase inhibitors to identify candidates possibly affecting the circadian period-length in mammalian cells. Screening by this high-throughput real-time bioluminescence monitoring system revealed that the several chemical compounds apparently lengthened the cellular circadian clock oscillation. These compounds are known as inhibitors against kinases such as Casein Kinase II (CKII), PI3-kinase (PI3K) and c-Jun N-terminal Kinase (JNK) in addition to CKIεδ. Although these kinase inhibitors may have some non-specific effects on other factors, our mini screening identified new candidates contributing to period-length control in mammalian cells

  18. Inhibitors

    Science.gov (United States)

    ... wrong place in the body. Immune Tolerance Induction (ITI) Therapy: The goal of ITI therapy is to stop the inhibitor reaction from ... body to accept clotting factor concentrate treatments. With ITI therapy, people receive large amounts of clotting factor ...

  19. Neuroinflammation induces glial aromatase expression in the uninjured songbird brain

    Directory of Open Access Journals (Sweden)

    Saldanha Colin J

    2011-07-01

    Full Text Available Abstract Background Estrogens from peripheral sources as well as central aromatization are neuroprotective in the vertebrate brain. Under normal conditions, aromatase is only expressed in neurons, however following anoxic/ischemic or mechanical brain injury; aromatase is also found in astroglia. This increased glial aromatization and the consequent estrogen synthesis is neuroprotective and may promote neuronal survival and repair. While the effects of estradiol on neuroprotection are well studied, what induces glial aromatase expression remains unknown. Methods Adult male zebra finches (Taeniopygia guttata were given a penetrating injury to the entopallium. At several timepoints later, expression of aromatase, IL-1β-like, and IL-6-like were examined using immunohisotchemistry. A second set of zebra birds were exposed to phytohemagglutinin (PHA, an inflammatory agent, directly on the dorsal surface of the telencephalon without creating a penetrating injury. Expression of aromatase, IL-1β-like, and IL-6-like were examined using both quantitative real-time polymerase chain reaction to examine mRNA expression and immunohistochemistry to determine cellular expression. Statistical significance was determined using t-test or one-way analysis of variance followed by the Tukey Kramers post hoc test. Results Following injury in the zebra finch brain, cytokine expression occurs prior to aromatase expression. This temporal pattern suggests that cytokines may induce aromatase expression in the damaged zebra finch brain. Furthermore, evoking a neuroinflammatory response characterized by an increase in cytokine expression in the uninjured brain is sufficient to induce glial aromatase expression. Conclusions These studies are among the first to examine a neuroinflammatory response in the songbird brain following mechanical brain injury and to describe a novel neuroimmune signal to initiate aromatase expression in glia.

  20. CES1 genetic variation affects the activation of angiotensin-converting enzyme inhibitors.

    Science.gov (United States)

    Wang, X; Wang, G; Shi, J; Aa, J; Comas, R; Liang, Y; Zhu, H-J

    2016-06-01

    The aim of the study was to determine the effect of carboxylesterase 1 (CES1) genetic variation on the activation of angiotensin-converting enzyme inhibitor (ACEI) prodrugs. In vitro incubation study of human liver, intestine and kidney s9 fractions demonstrated that the ACEI prodrugs enalapril, ramipril, perindopril, moexipril and fosinopril are selectively activated by CES1 in the liver. The impact of CES1/CES1VAR and CES1P1/CES1P1VAR genotypes and diplotypes on CES1 expression and activity on enalapril activation was investigated in 102 normal human liver samples. Neither the genotypes nor the diplotypes affected hepatic CES1 expression and activity. Moreover, among several CES1 nonsynonymous variants studied in transfected cell lines, the G143E (rs71647871) was a loss-of-function variant for the activation of all ACEIs tested. The CES1 activity on enalapril activation in human livers with the 143G/E genotype was approximately one-third of that carrying the 143G/G. Thus, some functional CES1 genetic variants (for example, G143E) may impair ACEI activation, and consequently affect therapeutic outcomes of ACEI prodrugs. PMID:26076923

  1. Paternal Retrieval Behavior Regulated by Brain Estrogen Synthetase (Aromatase) in Mouse Sires that Engage in Communicative Interactions with Pairmates

    Science.gov (United States)

    Akther, Shirin; Huang, Zhiqi; Liang, Mingkun; Zhong, Jing; Fakhrul, Azam A. K. M.; Yuhi, Teruko; Lopatina, Olga; Salmina, Alla B.; Yokoyama, Shigeru; Higashida, Chiharu; Tsuji, Takahiro; Matsuo, Mie; Higashida, Haruhiro

    2015-01-01

    Parental behaviors involve complex social recognition and memory processes and interactive behavior with children that can greatly facilitate healthy human family life. Fathers play a substantial role in child care in a small but significant number of mammals, including humans. However, the brain mechanism that controls male parental behavior is much less understood than that controlling female parental behavior. Fathers of non-monogamous laboratory ICR mice are an interesting model for examining the factors that influence paternal responsiveness because sires can exhibit maternal-like parental care (retrieval of pups) when separated from their pups along with their pairmates because of olfactory and auditory signals from the dams. Here we tested whether paternal behavior is related to femininity by the aromatization of testosterone. For this purpose, we measured the immunoreactivity of aromatase [cytochrome P450 family 19 (CYP19)], which synthesizes estrogen from androgen, in nine brain regions of the sire. We observed higher levels of aromatase expression in these areas of the sire brain when they engaged in communicative interactions with dams in separate cages. Interestingly, the number of nuclei with aromatase immunoreactivity in sires left together with maternal mates in the home cage after pup-removing was significantly larger than that in sires housed with a whole family. The capacity of sires to retrieve pups was increased following a period of 5 days spent with the pups as a whole family after parturition, whereas the acquisition of this ability was suppressed in sires treated daily with an aromatase inhibitor. The results demonstrate that the dam significantly stimulates aromatase in the male brain and that the presence of the pups has an inhibitory effect on this increase. These results also suggest that brain aromatization regulates the initiation, development, and maintenance of paternal behavior in the ICR male mice. PMID:26696812

  2. Aromatase Inhibitors and Other Compounds for Lowering Breast Cancer Risk

    Science.gov (United States)

    ... Cancer? Breast Cancer Colon/Rectum Cancer Lung Cancer Prostate Cancer Skin Cancer Show All Cancer Types News and Features Cancer Glossary ACS Bookstore Cancer Information Cancer Basics Cancer Prevention & Detection Signs & Symptoms of Cancer Treatments & Side Effects ...

  3. Neural stem cell sex dimorphism in aromatase (CYP19 expression: a basis for differential neural fate

    Directory of Open Access Journals (Sweden)

    Jay Waldron

    2010-11-01

    Full Text Available Jay Waldron1, Althea McCourty1, Laurent Lecanu1,21The Research Institute of the McGill University Health Centre, Montreal, Canada; 2Department of Medicine, McGill University, Quebec, CanadaPurpose: Neural stem cell (NSC transplantation and pharmacologic activation of endogenous neurogenesis are two approaches that trigger a great deal of interest as brain repair strategies. However, the success rate of clinical attempts using stem cells to restore neurologic functions altered either after traumatic brain injury or as a consequence of neurodegenerative disease remains rather disappointing. This suggests that factors affecting the fate of grafted NSCs are largely understudied and remain to be characterized. We recently reported that aging differentially affects the neurogenic properties of male and female NSCs. Although the sex steroids androgens and estrogens participate in the regulation of neurogenesis, to our knowledge, research on how gender-based differences affect the capacity of NSCs to differentiate and condition their neural fate is lacking. In the present study, we explored further the role of cell sex as a determining factor of the neural fate followed by differentiating NSCs and its relationship with a potential differential expression of aromatase (CYP19, the testosterone-metabolizing enzyme.Results: Using NSCs isolated from the subventricular zone of three-month-old male and female Long-Evans rats and maintained as neurospheres, we showed that differentiation triggered by retinoic acid resulted in a neural phenotype that depends on cell sex. Differentiated male NSCs mainly expressed markers of neuronal fate, including ßIII-tubulin, microtubule associated protein 2, growth-associated protein 43, and doublecortin. In contrast, female NSCs essentially expressed the astrocyte marker glial fibrillary acidic protein. Quantification of the expression of aromatase showed a very low level of expression in undifferentiated female NSCs

  4. Does selective serotonin reuptake inhibitor (SSRI) fluoxetine affects mussel Mytilus galloprovincialis?

    International Nuclear Information System (INIS)

    Fluoxetine (FLX) the active pharmaceutical ingredient (API) in Prozac® is a widely prescribed psychoactive drug which ubiquitous occurrence in the aquatic environment is associated to a poor removal rate in waste-water treatment plant (WWTP) systems. This API acts as a selective serotonin reuptake inhibitor (SSRI) frequently reported to cause disrupting effects in non-target species. The objective of this study includes a multibiomarker response evaluation on mussel Mytilus galloprovincialis during two weeks exposure to 75 ng L−1 FLX assessing antioxidant enzymes activities – superoxide dismutase (SOD), catalase (CAT) and glutathione-S-transferase (GST); lipid peroxidation (LPO), acetylcholinesterase (AChE) neurotoxic response and endocrine disruption through alkali-labile phosphates (ALP) indirect measurement of vitellogenin-like proteins. Results show transient tissue-specific enzymatic responses and damage affecting mostly mussel gills. However, the clear ALP levels inhibition throughout time in both sex-differentiated gonads gives evidence to FLX reinforced action as an endocrine disruptor rather than an oxidative or neurotoxic inducer. - Highlights: ► Short-time exposure of Mytilus galloprovincialis to antidepressant fluoxetine. ► Tissue-specific transient antioxidant enzymes activities alteration. ► Lipid peroxidation (LPO) induction in exposed-tissues. ► Acetylcholinesterase (AChE) activity upregulation in exposed gills. ► ALP levels downregulation in exposed sex-differentiated mussels. - Exposure to 75 ng L−1 antidepressant fluoxetine (FLX) induces tissue-specific multibiomarker responses alteration in mussel Mytilus galloprovincialis.

  5. Does selective serotonin reuptake inhibitor (SSRI) fluoxetine affects mussel Mytilus galloprovincialis?

    Science.gov (United States)

    Gonzalez-Rey, Maria; Bebianno, Maria João

    2013-02-01

    Fluoxetine (FLX) the active pharmaceutical ingredient (API) in Prozac(®) is a widely prescribed psychoactive drug which ubiquitous occurrence in the aquatic environment is associated to a poor removal rate in waste-water treatment plant (WWTP) systems. This API acts as a selective serotonin reuptake inhibitor (SSRI) frequently reported to cause disrupting effects in non-target species. The objective of this study includes a multibiomarker response evaluation on mussel Mytilus galloprovincialis during two weeks exposure to 75 ng L(-1) FLX assessing antioxidant enzymes activities--superoxide dismutase (SOD), catalase (CAT) and glutathione-S-transferase (GST); lipid peroxidation (LPO), acetylcholinesterase (AChE) neurotoxic response and endocrine disruption through alkali-labile phosphates (ALP) indirect measurement of vitellogenin-like proteins. Results show transient tissue-specific enzymatic responses and damage affecting mostly mussel gills. However, the clear ALP levels inhibition throughout time in both sex-differentiated gonads gives evidence to FLX reinforced action as an endocrine disruptor rather than an oxidative or neurotoxic inducer. PMID:23202651

  6. Cytochrome P450 aromatase expression in human seminoma

    OpenAIRE

    Montanaro Daniela; Aquila Saveria; Romeo Francesco; Rago Vittoria; Andò Sebastiano; Carpino Amalia

    2005-01-01

    Abstract Background The enzyme cytochrome P450 aromatase, catalysing the conversion of androgens into estrogens, has been detected in normal human testicular cells suggesting a physiological role of local estrogen biosynthesis on spermatogenesis control. Estrogens, regulating cell growth and apoptosis, can also be involved in tumorigenesis process, but the possible link between estrogens and testicular neoplastic process is, up to now, scarcely known. This study examined aromatase expression ...

  7. Aromatase expression is increased in BRCA1 mutation carriers

    International Nuclear Information System (INIS)

    Until recently, the molecular mechanisms explaining increased incidence of ovarian and breast cancers in carriers of BRCA1 gene mutations had not been clearly understood. Of significance is the finding that BRCA1 negatively regulates aromatase expression in vitro. Our objective was to characterise aromatase gene (CYP19A1) and its promoter expression in breast adipose and ovarian tissue in BRCA1 mutation carriers and unaffected controls. We measured aromatase transcripts, total and promoter-specific (PII, PI.3, PI.4) in prophylactic oophorectomy or mastectomy, therapeutic mastectomy, ovarian and breast tissue from unaffected women. We demonstrate that the lack of functional BRCA1 protein correlates to higher aromatase levels in 85% of BRCA1 mutation carriers. This increase is mediated by aberrant transcriptional regulation of aromatase; in breast adipose by increases in promoter II/I.3 and I.4-specific transcripts; and in the ovary with elevation in promoter I.3 and II-specific transcripts. Understanding the link between BRCA1 and aromatase is significant in terms of understanding why carcinogenesis is restricted to estrogen-producing tissues in BRCA1 mutation carriers

  8. The relationship of bone-tumor-induced spinal cord astrocyte activation and aromatase expression to mechanical hyperalgesia and cold hypersensitivity in intact female and ovariectomized mice.

    Science.gov (United States)

    Smeester, B A; O'Brien, E E; Michlitsch, K S; Lee, J-H; Beitz, A J

    2016-06-01

    Recently, our group established a relationship between tumor-induced spinal cord astrocyte activation and aromatase expression and the development of bone tumor nociception in male mice. As an extension of this work, we now report on the association of tumor-induced mechanical hyperalgesia and cold hypersensitivity to changes in spinal cord dorsal horn GFAP and aromatase expression in intact (INT) female mice and the effect of ovariectomy on these parameters. Implantation of fibrosarcoma cells produced robust mechanical hyperalgesia in INT animals, while ovariectomized (OVX) females had significantly less mechanical hyperalgesia. Cold hypersensitivity was apparent by post-implantation day 7 in INT and OVX females compared to their saline-injected controls and increased throughout the experiment. The decrease in mechanical hyperalgesia in OVX females was mirrored by significant decreases in spinal astrocyte activity in laminae I-II, III-IV, V-VI and X and aromatase expression in laminae V-VI and X in the dorsal horn of tumor-bearing animals. Administration of the aromatase inhibitor letrozole reduced tumor-induced hyperalgesia in INT females only suggesting that the tumor-induced increase in aromatase expression and its associated increase in spinal estrogen play a role in the development of bone tumor-induced hyperalgesia. Finally, intrathecal (i.t.) administration of 17β-estradiol caused a significant increase in tumor-induced hyperalgesia in INT tumor-bearing females. Since i.t. 17β-estradiol increases tumor pain and ovariectomy significantly decreases tumor pain, as well as spinal aromatase, estrogen may play a critical role in the spinal cord response to the changing tumor environment and the development of tumor-induced nociception. PMID:26995084

  9. The bone resorption inhibitors odanacatib and alendronate affect post-osteoclastic events differently in ovariectomized rabbits.

    Science.gov (United States)

    Jensen, Pia Rosgaard; Andersen, Thomas Levin; Pennypacker, Brenda L; Duong, Le T; Delaissé, Jean-Marie

    2014-02-01

    Odanacatib (ODN) is a bone resorption inhibitor which differs from standard antiresorptives by its ability to reduce bone resorption without decreasing bone formation. What is the reason for this difference? In contrast with other antiresorptives, such as alendronate (ALN), ODN targets only the very last step of the resorption process. We hypothesize that ODN may therefore modify the remodeling events immediately following osteoclastic resorption. These events belong to the reversal phase and include recruitment of osteoblasts, which is critical for connecting bone resorption to formation. We performed a histomorphometric study of trabecular remodeling in vertebrae of estrogen-deficient rabbits treated or not with ODN or ALN, a model where ODN, but not ALN, was previously shown to preserve bone formation. In line with our hypothesis, we found that ODN treatment compared to ALN results in a shorter reversal phase, faster initiation of osteoid deposition on the eroded surfaces, and higher osteoblast recruitment. The latter is reflected by higher densities of mature bone forming osteoblasts and an increased subpopulation of cuboidal osteoblasts. Furthermore, we found an increase in the interface between osteoclasts and surrounding osteoblast-lineage cells. This increase is expected to favor the osteoclast-osteoblast interactions required for bone formation. Regarding bone resorption itself, we show that ODN, but not ALN, treatment results in shallower resorption lacunae, a geometry favoring bone stiffness. We conclude that, compared to standard antiresorptives, ODN shows distinctive effects on resorption geometry and on reversal phase activities which positively affect osteoblast recruitment and may therefore favor bone formation. PMID:24085265

  10. Detergents profoundly affect inhibitor potencies against both cyclo-oxygenase isoforms.

    Science.gov (United States)

    Ouellet, Marc; Falgueyret, Jean-Pierre; Percival, M David

    2004-02-01

    The sensitivity of Coxs (cyclo-oxygenases) to inhibition is known to be highly dependent on assay conditions. In the present study, the inhibitor sensitivities of purified Cox-1 and -2 were determined in a colorimetric assay using the reducing agent N, N, N ', N '-tetramethyl- p -phenylenediamine. With the detergent genapol X-100 (2 mM) present, the potencies of nimesulide, ibuprofen, flufenamic acid, niflumic acid and naproxen were increased over 100-fold against Cox-2 and titration curve shapes changed, so that maximal inhibition now approached 100%. Indomethacin, diclofenac and flosulide were not changed in potency. Similar effects of genapol were observed with inhibitors of Cox-1. DuP-697 and two analogues became more than 10-fold less potent against Cox-2 with genapol present. Tween-20, Triton X-100 and phosphatidylcholine, but not octylglucoside, gave qualitatively similar effects as genapol. Similar detergent-dependent changes in inhibitor potency were also observed using a [(14)C]arachidonic acid HPLC assay. The increases in potency of ibuprofen, flufenamic acid, isoxicam and niflumic acid towards Cox-2 and ibuprofen towards Cox-1 were accompanied by a change from time-independent to time-dependent inhibition. The interactions of Cox inhibitors has been described in terms of multiple binding step mechanisms. The genapol-dependent increase in inhibitor potency for ketoprofen was associated with an increase in the rate constant for the conversion of the initial enzyme-inhibitor complex to a second, more tightly bound form. The loss of potency for some inhibitors is probably due to inhibitor partitioning into detergent micelles. The present study identifies detergents as another factor that must be considered when determining inhibitor potencies against both Cox isoforms. PMID:14510637

  11. Selective Serotonin Reuptake Inhibitors Affect Neurobehavioral Development in the Human Fetus

    NARCIS (Netherlands)

    Mulder, Eduard J. H.; Ververs, Frederique F. T.; de Heus, Roel; Visser, Gerard H. A.

    2011-01-01

    The aim of this prospective study was to investigate whether selective serotonin reuptake inhibitors (SSRIs) utilized by pregnant women influence fetal neurobehavioral development. In this observational study we investigated developmental milestones of fetal behavior during the pregnancy of women wi

  12. The CYP2C8 inhibitor gemfibrozil does not affect the pharmacokinetics of zafirlukast

    OpenAIRE

    Karonen, Tiina; Neuvonen, Pertti J; Backman, Janne T.

    2010-01-01

    Abstract Purpose Gemfibrozil, a strong inhibitor of cytochrome P450 (CYP) 2C8 in vivo, was recently found to markedly increase the plasma concentrations of montelukast in humans. Like montelukast, zafirlukast is a substrate of CYP2C9 and CYP3A4 and a potent inhibitor of CYP2C8 in vitro. To investigate the contribution of CYP2C8 to the metabolism of zafirlukast in vivo, we studied the effect of gemfibrozil on the pharmacokinetics of zafirlukast. ...

  13. Regulatory proteins (inhibitors or activators) affect estimates of Msub(r) of enzymes and receptors by radiation inactivation

    International Nuclear Information System (INIS)

    The radiation-inactivation method allows the determination of the Msub(r) of enzymes and receptors by monitoring the decay of biological activity as a function of absorbed dose. The presence of regulatory or effector proteins (inhibitors or activators) associated with an enzyme or receptor, or released in the preparation after tissue homogenization, may affect the decay of biological activity. How the activity is affected, however, will depend on the type of inhibition (competitive or non-competitive), the inhibitor or activator concentration, the dissociation constant of the enzyme-effector system, and the effector Msub(r) relative to that of the enzyme. Since little is known on how effector proteins influence radiation inactivation of enzymes and receptors, we have considered a theoretical model in an effort to provide a framework for the interpretation of experimentally obtained data. Our model predicts that competitive and non-competitive inhibitors of enzymes could be distinguished by analysing irradiated samples with various substrate concentrations. Inhibitors will decrease whereas activators will increase the apparent target size of enzymes or receptors. (author)

  14. Performance of water-based foams affected by chemical inhibitors to retard spontaneous combustion of coal

    Institute of Scientific and Technical Information of China (English)

    Chen Peng; Huang Fujun; Fu Yue

    2016-01-01

    The micelle generating process of the sodium dodecyl sulfate (SDS) solution with the addition of chemical inhibitors was elucidated using phase separation model, and the descending order of the capacity for the selected chemical inhibitors to reduce the critical micelle concentrations of the solution are MgCl2, CaCl2, NH4HCO3 and NH4Cl. The data to quantitatively describe the foam decay process, including foaming ratio, foam life and decay behaviors, was obtained by pressure measuring system. The results indicate that chemical inhibitors can improve the solution foamability. The capacity of the inhibitors to enhance the solution foamability is sorted as NH4Cl, NH4HCO3, MgCl2 and CaCl2 which can distinctly improve the foam stability as well. The capacity of the inhibitors to enhance the SDS foam stability can be arranged as MgCl2, NH4Cl, NH4HCO3 and CaCl2. It is observed that the gravity drainage plays a leading role in the increase of proportion of diffusion drainage. The oxidation dynamic parameters of the coal samples trea-ted by inhibition foams were investigated using thermal analysis technique, and their synergistic effects on inhibiting coal oxidation were explored.

  15. Expression of aromatase and estrogen receptor alpha in chondrosarcoma, but no beneficial effect of inhibiting estrogen signaling both in vitro and in vivo

    Directory of Open Access Journals (Sweden)

    Meijer Danielle

    2011-07-01

    Full Text Available Abstract Background Chondrosarcomas are malignant cartilage-forming tumors which are highly resistant to conventional chemotherapy and radiotherapy. Estrogen signaling is known to play an important role in proliferation and differentiation of chondrocytes and in growth plate regulation at puberty. Our experiments focus on unraveling the role of estrogen signaling in the regulation of neoplastic cartilage growth and on interference with estrogen signaling in chondrosarcomas in vitro and in vivo. Methods We investigated the protein expression of estrogen receptor alpha (ESR1, androgen receptor (AR, and aromatase in tumor specimens of various chondrosarcoma subtypes, and (primary chondrosarcoma cultures. Dose-response curves were generated of conventional central chondrosarcoma cell lines cultured in the presence of 17β-estradiol, dihydrotestosterone, 4-androstene-3,17 dione, 4-hydroxytamoxifen, fulvestrant and aromatase inhibitors. In a pilot series, the effect of anastrozole (n = 4 or exemestane (n = 2 treatment in 6 chondrosarcoma patients with progressive disease was explored. Results We showed protein expression of ESR1 and aromatase in a large majority of all subtypes. Only a minority of the tumors showed few AR positive cells. The dose-response assays showed no effect of any of the compounds on proliferation of conventional chondrosarcoma in vitro. The median progression-free survival of the patients treated with aromatase inhibitors did not significantly deviate from untreated patients. Conclusions The presence of ESR1 and aromatase in chondrosarcoma tumors and primary cultures supports a possible role of estrogen signaling in chondrosarcoma proliferation. However, our in vitro and pilot in vivo studies have shown no effect of estrogen-signaling inhibition on tumor growth.

  16. Aromatase immunolocalization in human ductuli efferentes and proximal ductus epididymis.

    Science.gov (United States)

    Carpino, A; Romeo, F; Rago, V

    2004-03-01

    Abstract Cytochrome P450 aromatase is a terminal enzyme that catalyses the conversion of androgens into oestrogens. This study investigated the immunohistochemical localization of aromatase in human efferent ductules and proximal ductus epididymis using a mouse anti-human monoclonal P450arom IgG as primary antibody and a goat anti-mouse biotinylated IgG as secondary antibody. A strong immunoreaction was observed in the epithelial cell cytoplasm of both ductuli efferentes and proximal ductus epididymis, whereas the smooth muscle cells were immunonegative in the two regions. The results show, for the first time in humans, that epithelial cells of ductuli efferentes and proximal caput epididymis express aromatase, suggesting that locally produced oestrogens may have a role in epididymal function. PMID:15032911

  17. Aminocarnitine and acylaminocarnitines: Carnitine acyltransferase inhibitors affecting long-chain fatty acid and glucose metabolism

    Energy Technology Data Exchange (ETDEWEB)

    Clark, D.J.

    1989-01-01

    DL-Aminocarnitine (DL-3-amino-4-trimethylaminobutyrate) and the acylaminocarnitines acetyl-, decanoyl- and palmitoyl-DL-aminocarnitine have been synthesized and tested as inhibitors of carnitine palmitoyl-transferase and carnitine acetyltransferase in vitro and in vivo. Acetyl-DL-aaminocarnitine is the most potent reversible inhibitor of carnitine acetyltransferase reported to date, and is competitive with respect to acetyl-L-carnitine. Mice given acetyl-DL-aminocarnitine metabolize (U-{sup 14}C)acetyl-L-carnitine at about 60% of the rate of control mice. Palmitoyl-DL-aminocarnitine is the most potent reversible inhibitor of carnitine palmitoyltransferase reported to date. Decanoyl-DL-aminocarnitine and DL-aminocarnitine are also very potent inhibitors; all compounds inhibit the catabolism of ({sup 14}C)palmitate to {sup 14}CO{sub 2} in intact mice by at least 50%. Carnitine palmitoyltransferase controls the entry of long-chain fatty acids into the mitochondrial matrix for {beta}-oxidation. The inhibition of carnitine palmitoyltransferase by aminocarnitine or acylaminocarnitines in vivo prevents or reverses ketogenesis in fasted mice, and causes the reversible accumulation of triglycerides in liver, kidney and plasma. Administration of DL-aminocarnitine to streptozotocindiabetic mice lowers plasma glucose levels and improves the glucose tolerance test.

  18. Aminocarnitine and acylaminocarnitines: Carnitine acyltransferase inhibitors affecting long-chain fatty acid and glucose metabolism

    International Nuclear Information System (INIS)

    DL-Aminocarnitine (DL-3-amino-4-trimethylaminobutyrate) and the acylaminocarnitines acetyl-, decanoyl- and palmitoyl-DL-aminocarnitine have been synthesized and tested as inhibitors of carnitine palmitoyl-transferase and carnitine acetyltransferase in vitro and in vivo. Acetyl-DL-aaminocarnitine is the most potent reversible inhibitor of carnitine acetyltransferase reported to date, and is competitive with respect to acetyl-L-carnitine. Mice given acetyl-DL-aminocarnitine metabolize [U-14C]acetyl-L-carnitine at about 60% of the rate of control mice. Palmitoyl-DL-aminocarnitine is the most potent reversible inhibitor of carnitine palmitoyltransferase reported to date. Decanoyl-DL-aminocarnitine and DL-aminocarnitine are also very potent inhibitors; all compounds inhibit the catabolism of [14C]palmitate to 14CO2 in intact mice by at least 50%. Carnitine palmitoyltransferase controls the entry of long-chain fatty acids into the mitochondrial matrix for β-oxidation. The inhibition of carnitine palmitoyltransferase by aminocarnitine or acylaminocarnitines in vivo prevents or reverses ketogenesis in fasted mice, and causes the reversible accumulation of triglycerides in liver, kidney and plasma. Administration of DL-aminocarnitine to streptozotocindiabetic mice lowers plasma glucose levels and improves the glucose tolerance test

  19. Bowman-Birk inhibitor affects pathways associated with energy metabolism in Drosophila melanogaster

    Science.gov (United States)

    Bowman-Birk inhibitor (BBI) is toxic when fed to certain insects, including the fruit fly, Drosophila melanogaster. Dietary BBI has been demonstrated to slow growth and increase insect mortality by inhibiting the digestive enzymes trypsin and chymotrypsin, resulting in a reduced supply of amino acid...

  20. The Bone Resorption Inhibitors Odanacatib and Alendronate Affect Post-Osteoclastic Events Differently in Ovariectomized Rabbits

    DEFF Research Database (Denmark)

    Jensen, Pia Rosgaard; Andersen, Thomas Levin; Pennypacker, Brenda L;

    2014-01-01

    Odanacatib (ODN) is a bone resorption inhibitor which differs from standard antiresorptives by its ability to reduce bone resorption without decreasing bone formation. What is the reason for this difference? In contrast with other antiresorptives, such as alendronate (ALN), ODN targets only the...

  1. The tyrosine kinase inhibitor sunitinib affects ovulation but not ovarian reserve in mouse: A preclinical study

    NARCIS (Netherlands)

    V. Bernard (Valérie); J. Bouilly (Justine); P. Kramer (Piet); N. Carré (Nadège); M. Schlumberger (Martin); J.A. Visser (Jenny A.); J. Young (Jacques); N.B. Binart (Nadine Binart)

    2016-01-01

    textabstractThe aim of the study was to evaluate ovarian toxicity of tyrosine kinase inhibitor (TKI) sunitinib, since only scarce data are available on gonadal function after this treatment. Six-weekold female mice received orally, once daily, vehicle or sunitinib (50 mg/kg/d) during 5 weeks. Fertil

  2. Dabigatran and rivaroxaban do not affect AA- and ADP-induced platelet aggregation in patients receiving concomitant platelet inhibitors.

    Science.gov (United States)

    Olivier, Christoph B; Weik, Patrick; Meyer, Melanie; Weber, Susanne; Diehl, Philipp; Bode, Christoph; Moser, Martin; Zhou, Qian

    2016-08-01

    Dabigatran and rivaroxaban are novel, vitamin K-independent oral anticoagulants (NOACs) and act via antagonism of the coagulation factor (F) IIa (dabigatran) or FXa (rivaroxaban), respectively. Compared to vitamin-K-antagonists, NOACs have shown non-inferiority of risk and benefit in patients with non valvular atrial fibrillation (AF). In clinical practice there is increasing use of NOACs combined with platelet inhibitors in patients with AF and coronary artery disease. However, whether NOACs affect the function of platelet inhibitors remains incompletely known. This observational study aimed to assess the platelet function in patients receiving dabigatran or rivaroxaban and concomitant platelet inhibitors. A single centre observational study was performed analysing the platelet aggregation of patients treated with dabigatran or rivaroxaban with or without concomitant platelet inhibitors. Measurements before the initiation of NOAC therapy served as the respective control group. Platelet aggregation was measured by multiple electrode aggregometry and was induced with adenosine diphosphate (ADP, 6.5 µM) and arachidonic acid (AA, 0.5 mM), respectively. In order to evaluate whether NOACs interact with platelet inhibition by ASA or the P2Y12-antagonist clopidogrel, 87 patients were grouped according to their concomitant antiplatelet medication. Comparing the ADP- and AA-induced platelet aggregation in patients without concomitant platelet inhibitors (n = 45) no significant differences under therapy with dabigatran (d) or rivaroxaban (r) compared to the control group (c) were observed. In patients taking clopidogrel as a concomitant platelet inhibitor (n = 21), neither dabigatran nor rivaroxaban affected the ADP-induced platelet aggregation (c 20 ± 11, d 21 ± 14, r 18 ± 8 AU*min, p = 0.200). Patients receiving dabigatran or rivaroxaban in combination with ASA (n = 42; 21 ASA only, 21 ASA + clopidogrel) showed no significant differences of the AA

  3. Design, validation and efficacy of bisubstrate inhibitors specifically affecting ecto-CK2 kinase activity.

    Science.gov (United States)

    Cozza, Giorgio; Zanin, Sofia; Sarno, Stefania; Costa, Elena; Girardi, Cristina; Ribaudo, Giovanni; Salvi, Mauro; Zagotto, Giuseppe; Ruzzene, Maria; Pinna, Lorenzo A

    2015-11-01

    By derivatizing the purely competitive CK2 inhibitor N1-(4,5,6,7-tetrabromo-1H-benzimidazol-2-yl)-propane-1,3-diamine (K137) at its 3-amino position with a peptidic fragment composed of three or four glutamic or aspartic acid residues, a new family of bisubstrate inhibitors has been generated whose ability to simultaneously interact with both the ATP and the phosphoacceptor substrate-binding sites has been probed by running mixed competition kinetics and by mutational mapping of the kinase residues implicated in substrate recognition. The most effective bisubstrate inhibitor, K137-E4, interacts with three functional regions of the kinase: the hydrophobic pocket close to the ATP-binding site, the basic residues of the p+1 loop that recognizes the acidic determinant at position n+1 and the basic residues of α-helixC that recognize the acidic determinant at position n+3. Compared with the parent inhibitor (K137), K137-E4 is severalfold more potent (IC50 25 compared with 130 nM) and more selective, failing to inhibit any other kinase as drastically as CK2 out of 140 enzymes, whereas 35 kinases are inhibited more potently than CK2 by K137. K137-E4 is unable to penetrate the cell and to inhibit endogenous CK2, its pro-apoptotic efficacy being negligible compared with cell-permeant inhibitors; however, it readily inhibits ecto-CK2 on the outer cell surface, reducing the phosphorylation of several external phosphoproteins. Inhibition of ecto-CK2 by K137-E4 is accompanied by a slower migration of cancer cells as judged by wound healing assays. On the basis of the cellular responses to K137-E4, we conclude that ecto-CK2 is implicated in cell motility, whereas its contribution to the pro-survival role of CK2 is negligible. PMID:26349539

  4. The pharmacokinetics of darexaban (YM150), an oral direct factor Xa inhibitor, are not affected by ketoconazole, a strong inhibitor of CYP3A and P-glycoprotein.

    Science.gov (United States)

    Groenendaal, Dorien; Strabach, Gregory; Garcia-Hernandez, Alberto; Kadokura, Takeshi; Heeringa, Marten; Mol, Roelof; Eltink, Charlotte; Onkels, Hartmut

    2014-05-01

    We investigated the effects of ketoconazole on the pharmacokinetics (PK) of the direct clotting factor Xa inhibitor darexaban (YM150) and its main active metabolite darexaban glucuronide (YM-222714) which almost entirely determines the antithrombotic effect. In this open-label, randomized, two-period crossover study, 26 healthy male volunteers received in one treatment period a single dose of darexaban 60 mg, and in the other treatment period, ketoconazole 400 mg once daily on Days 1-9 with a single dose of darexaban 60 mg on Day 4. Washout between periods was at least 1 week. The geometric mean ratio (90% confidence interval) of darexaban glucuronide (darexaban plus ketoconazole versus darexaban) for AUCinf was 1.11 (1.00, 1.23), and for Cmax 1.18 (1.03, 1.35). Darexaban concentrations remained very low (AUClast ∼196-fold lower) in relation to darexaban glucuronide concentrations. In conclusion, the PK of darexaban glucuronide was not affected to a clinically relevant degree by co-administration of the strong CYP3A/P-glycoprotein inhibitor, ketoconazole. The PK of the parent compound darexaban were changed, however, concentrations remained quantitatively insignificant in relation to the main active moiety, darexaban glucuronide. PMID:27128609

  5. The Bone Resorption Inhibitors Odanacatib and Alendronate Affect Post-Osteoclastic Events Differently in Ovariectomized Rabbits

    OpenAIRE

    Jensen, Pia Rosgaard; Andersen, Thomas Levin; Pennypacker, Brenda L; Duong, Le T.; Delaissé, Jean-Marie

    2013-01-01

    Odanacatib (ODN) is a bone resorption inhibitor which differs from standard antiresorptives by its ability to reduce bone resorption without decreasing bone formation. What is the reason for this difference? In contrast with other antiresorptives, such as alendronate (ALN), ODN targets only the very last step of the resorption process. We hypothesize that ODN may therefore modify the remodeling events immediately following osteoclastic resorption. These events belong to the reversal phase and...

  6. Glycosaminoglycans affect the interaction of human plasma kallikrein with plasminogen, factor XII and inhibitors

    Directory of Open Access Journals (Sweden)

    Gozzo A.J.

    2003-01-01

    Full Text Available Human plasma kallikrein, a serine proteinase, plays a key role in intrinsic blood clotting, in the kallikrein-kinin system, and in fibrinolysis. The proteolytic enzymes involved in these processes are usually controlled by specific inhibitors and may be influenced by several factors including glycosaminoglycans, as recently demonstrated by our group. The aim of the present study was to investigate the effect of glycosaminoglycans (30 to 250 µg/ml on kallikrein activity on plasminogen and factor XII and on the inhibition of kallikrein by the plasma proteins C1-inhibitor and antithrombin. Almost all available glycosaminoglycans (heparin, heparan sulfate, bovine and tuna dermatan sulfate, chondroitin 4- and 6-sulfates reduced (1.2 to 3.0 times the catalytic efficiency of kallikrein (in a nanomolar range on the hydrolysis of plasminogen (0.3 to 1.8 µM and increased (1.9 to 7.7 times the enzyme efficiency in factor XII (0.1 to 10 µM activation. On the other hand, heparin, heparan sulfate, and bovine and tuna dermatan sulfate improved (1.2 to 3.4 times kallikrein inhibition by antithrombin (1.4 µM, while chondroitin 4- and 6-sulfates reduced it (1.3 times. Heparin and heparan sulfate increased (1.4 times the enzyme inhibition by the C1-inhibitor (150 nM.

  7. Inhibition of human aromatase complex (CYP19) by antiepileptic drugs

    DEFF Research Database (Denmark)

    Jacobsen, Naja Wessel; Halling-Sørensen, Bent; Birkved, Franziska Maria A Kramer

    2008-01-01

    Antiepileptic drugs and epilepsy are often associated with sexual disorder in women such as hyperandrogenism, menstrual disorders and ovarian cysts. In children, until puberty, a hormone imbalance may influence many aspects of development, e.g. growth and sexual maturation. The aromatase complex is...

  8. The effects of COX-Inhibitors (Diclofenac and Ibuprofen on growth rate, mortality and sex reversal in Nile Tilapia (Oreochromis niloticus

    Directory of Open Access Journals (Sweden)

    Mutaz A. Al-Qutob

    2009-10-01

    similar to those of control. Postulated mechanisms of action of the supplemented COX-inhibitors are discussed. Based on the above it can be concluded that the use of COX-Inhibitors during the crucial period could modulate aromatase activity and affect reproduction in Nile tilapia.

  9. Age-related decrease in aromatase and estrogen receptor(ERαand ERβ) expression in rat testes: protective effect of low caloric diets

    Institute of Scientific and Technical Information of China (English)

    Khaled Hamden; Dorothee Silandre; Christelle Delalande; Abdefattah El Feki; Serge Carreau

    2008-01-01

    Aim: To examine the effects on rat aging of caloric restriction (CR1) and undernutrition (CR2) on the body and on testicular weights, on two enzymatic antioxidants (superoxide dismutase and catalase), on lipid peroxidation and on the expression of testicular aromatase and estrogen receptors (ER). Methods: CR was initiated in 1-month-old rats and carried on until the age of 18 months. Results: In control and CR2 rats an age-related decrease of the aromatase and of ER (α and β) gene expression was observed; in parallel a diminution of testicular weights, and of the total number and motility of epididymal spermatozo was recorded. In addition, aging in control and CR2 rats was accom-panied by a significant decrease in testicular superoxide dismutase, catalase activities, and an increase in lipid peroxidation level (thiobarbituric acid reactive substance), associated with alterations of spermatogenesis. Conversely, caloric restriction-treatment exerted a protective effect and all the parameters were less affected by aging. Conclusion:These results indicate that during aging, a low caloric diet (not undernutrition) is beneficial for spermatogenesis and likely improves the protection of the cells via an increase of the cellular antioxidant defense system in which aromatase/ER could play a role.

  10. The Tyrosine Kinase Inhibitor Sunitinib Affects Ovulation but Not Ovarian Reserve in Mouse: A Preclinical Study

    Science.gov (United States)

    Bernard, Valérie; Bouilly, Justine; Kramer, Piet; Carré, Nadège; Schlumberger, Martin; Visser, Jenny A.; Young, Jacques; Binart, Nadine

    2016-01-01

    The aim of the study was to evaluate ovarian toxicity of tyrosine kinase inhibitor (TKI) sunitinib, since only scarce data are available on gonadal function after this treatment. Six-week-old female mice received orally, once daily, vehicle or sunitinib (50 mg/kg/d) during 5 weeks. Fertility parameters were analyzed from ovulation to litter assessment. Sunitinib exposure significantly reduced (i) corpora lutea number per ovary (1.1 ± 0.38 in sunitinib group versus 4 ± 0.79 in control group, p<0.01) and (ii) serum Anti Müllerian hormone (AMH) levels in sunitinib treated mice (12.01 ± 1.16) compared to control mice (14.33 ± 0.87 ng/ml, p< 0.05). However, primordial and growing follicles numbers per ovary were not different in both groups. After treatment withdrawal, female mice in both groups were able to obtain litters. These data could be helpful to counsel clinicians and patients, when fertility preservation methods are discussed, before TKI treatment in girls and young women. PMID:27035144

  11. The Tyrosine Kinase Inhibitor Sunitinib Affects Ovulation but Not Ovarian Reserve in Mouse: A Preclinical Study.

    Directory of Open Access Journals (Sweden)

    Valérie Bernard

    Full Text Available The aim of the study was to evaluate ovarian toxicity of tyrosine kinase inhibitor (TKI sunitinib, since only scarce data are available on gonadal function after this treatment. Six-week-old female mice received orally, once daily, vehicle or sunitinib (50 mg/kg/d during 5 weeks. Fertility parameters were analyzed from ovulation to litter assessment. Sunitinib exposure significantly reduced (i corpora lutea number per ovary (1.1 ± 0.38 in sunitinib group versus 4 ± 0.79 in control group, p<0.01 and (ii serum Anti Müllerian hormone (AMH levels in sunitinib treated mice (12.01 ± 1.16 compared to control mice (14.33 ± 0.87 ng/ml, p< 0.05. However, primordial and growing follicles numbers per ovary were not different in both groups. After treatment withdrawal, female mice in both groups were able to obtain litters. These data could be helpful to counsel clinicians and patients, when fertility preservation methods are discussed, before TKI treatment in girls and young women.

  12. The Tyrosine Kinase Inhibitor Sunitinib Affects Ovulation but Not Ovarian Reserve in Mouse: A Preclinical Study.

    Science.gov (United States)

    Bernard, Valérie; Bouilly, Justine; Kramer, Piet; Carré, Nadège; Schlumberger, Martin; Visser, Jenny A; Young, Jacques; Binart, Nadine

    2016-01-01

    The aim of the study was to evaluate ovarian toxicity of tyrosine kinase inhibitor (TKI) sunitinib, since only scarce data are available on gonadal function after this treatment. Six-week-old female mice received orally, once daily, vehicle or sunitinib (50 mg/kg/d) during 5 weeks. Fertility parameters were analyzed from ovulation to litter assessment. Sunitinib exposure significantly reduced (i) corpora lutea number per ovary (1.1 ± 0.38 in sunitinib group versus 4 ± 0.79 in control group, p<0.01) and (ii) serum Anti Müllerian hormone (AMH) levels in sunitinib treated mice (12.01 ± 1.16) compared to control mice (14.33 ± 0.87 ng/ml, p< 0.05). However, primordial and growing follicles numbers per ovary were not different in both groups. After treatment withdrawal, female mice in both groups were able to obtain litters. These data could be helpful to counsel clinicians and patients, when fertility preservation methods are discussed, before TKI treatment in girls and young women. PMID:27035144

  13. Differential expression of genes for aromatase and estrogen receptor during the gonadal development in chicken embryos.

    Science.gov (United States)

    Nakabayashi, O; Kikuchi, H; Kikuchi, T; Mizuno, S

    1998-04-01

    In birds, differentiation of embryonic gonads is not as strictly determined by the genetic sex as it is in mammals, and can be influenced by early manipulation with a sex steroid hormone. Thus administration of an aromatase inhibitor induces testis development in the genetic female, and administration of estrogen induces a left ovotestis in the genetic male embryo. Another feature of avian gonadogenesis is that only the left ovary develops in most species. Molecular mechanisms underlying these features at the level of gene expression have not been elucidated. In this paper, we present evidence that a gene for aromatase cytochrome P-450, an enzyme required for the last step in the synthesis of estradiol-17beta, is expressed in medullae of the left and right gonads of a female chicken embryo, but not in those of a male chicken embryo, and that an estrogen receptor gene is expressed only in epithelium (and cortex later, in the female) of the left, not the right, gonad of both sexes, but the expression in the male left gonad is temporary and restricted to an early stage of development. Differential expression of these two genes serves well to explain the above features of gonadal development in birds. Furthermore, in ovo administration of estradiol-17beta from the 5th to the 14th day of incubation does not cause expression of the estrogen receptor gene in the right gonad of chicken embryos of either sex, suggesting that the absence of expression of the estrogen receptor gene in the right gonad is not the result of down-regulation, but may be regarded as an important cause of the unilateral ovarian development. PMID:9584834

  14. The ferrous-oxy complex of human aromatase

    International Nuclear Information System (INIS)

    In this communication, we document the self-assembly of heterologously expressed truncated human aromatase (CYP19) into nanometer scale phospholipids bilayers (Nanodiscs). The resulting P450 CYP19 preparation is stable and can tightly associate with the substrate androstenedione to form a nearly complete high-spin ferric protein. Ferrous CYP19 in Nanodiscs was mixed anaerobically in a rapid-scan stopped-flow with atmospheric dioxygen and the formation of the ferrous-oxy complex observed. First order decay of the oxy-complex to release superoxide and regenerate the ferric enzyme was monitored kinetically. Surprisingly, the ferrous-oxy complex of aromatase is more stable than that of hepatic CYP3A4, opening the path to precisely determine the biochemical and biophysical properties of the reaction cycle intermediates in this important human drug target

  15. Perfluorinated chemicals: Differential toxicity, inhibition of aromatase activity and alteration of cellular lipids in human placental cells

    Energy Technology Data Exchange (ETDEWEB)

    Gorrochategui, Eva; Pérez-Albaladejo, Elisabet [Department of Environmental Chemistry, IDAEA–CSIC, 08034 Barcelona, Catalonia (Spain); Casas, Josefina [Department of Biomedicinal Chemistry, IQAC–CSIC, 08034 Barcelona, Catalonia (Spain); Lacorte, Sílvia, E-mail: slbqam@cid.csic.es [Department of Environmental Chemistry, IDAEA–CSIC, 08034 Barcelona, Catalonia (Spain); Porte, Cinta, E-mail: cinta.porte@cid.csic.es [Department of Environmental Chemistry, IDAEA–CSIC, 08034 Barcelona, Catalonia (Spain)

    2014-06-01

    The cytotoxicity of eight perfluorinated chemicals (PFCs), namely, perfluorobutanoic acid (PFBA), perfluorohexanoic acid (PFHxA), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorododecanoic acid (PFDoA), perfluorobutanesulfonate (PFBS), perfluorohexanesulfonate (PFHxS) and perfluorooctanesulfonate (PFOS) was assessed in the human placental choriocarcinoma cell line JEG-3. Only the long chain PFCs – PFOS, PFDoA, PFNA, PFOA – showed significant cytotoxicity in JEG-3 cells with EC50 values in the range of 107 to 647 μM. The observed cytotoxicity was to some extent related to a higher uptake of the longer chain PFCs by cells (PFDoA > PFOS ≫ PFNA > PFOA > PFHxA). Moreover, this work evidences a high potential of PFOS, PFOA and PFBS to act as aromatase inhibitors in placental cells with IC50s in the range of 57–80 μM, the inhibitory effect of PFBS being particularly important despite the rather low uptake of the compound by cells. Finally, exposure of JEG-3 cells to a mixture of the eight PFCs (0.6 μM each) led to a relative increase (up to 3.4-fold) of several lipid classes, including phosphatidylcholines (PCs), plasmalogen PC and lyso plasmalogen PC, which suggests an interference of PFCs with membrane lipids. Overall, this work highlights the ability of the PFC mixture to alter cellular lipid pattern at concentrations well below those that generate toxicity, and the potential of the short chain PFBS, often considered a safe substitute of PFOS, to significantly inhibit aromatase activity in placental cells. - Highlights: • Eight perfluorinated chemicals of different chain lengths have been selected. • Long chain ones – PFOS, PFDoA, PFNA, PFOA – were cytotoxic in placenta cells. • The uptake of long chain perfluorinated chemicals by cells was comparatively higher. • PFOS, PFOA and the short chain PFBS significantly inhibited aromatase activity. • A mixture of perfluorinated chemicals significantly altered placenta cell

  16. Perfluorinated chemicals: Differential toxicity, inhibition of aromatase activity and alteration of cellular lipids in human placental cells

    International Nuclear Information System (INIS)

    The cytotoxicity of eight perfluorinated chemicals (PFCs), namely, perfluorobutanoic acid (PFBA), perfluorohexanoic acid (PFHxA), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorododecanoic acid (PFDoA), perfluorobutanesulfonate (PFBS), perfluorohexanesulfonate (PFHxS) and perfluorooctanesulfonate (PFOS) was assessed in the human placental choriocarcinoma cell line JEG-3. Only the long chain PFCs – PFOS, PFDoA, PFNA, PFOA – showed significant cytotoxicity in JEG-3 cells with EC50 values in the range of 107 to 647 μM. The observed cytotoxicity was to some extent related to a higher uptake of the longer chain PFCs by cells (PFDoA > PFOS ≫ PFNA > PFOA > PFHxA). Moreover, this work evidences a high potential of PFOS, PFOA and PFBS to act as aromatase inhibitors in placental cells with IC50s in the range of 57–80 μM, the inhibitory effect of PFBS being particularly important despite the rather low uptake of the compound by cells. Finally, exposure of JEG-3 cells to a mixture of the eight PFCs (0.6 μM each) led to a relative increase (up to 3.4-fold) of several lipid classes, including phosphatidylcholines (PCs), plasmalogen PC and lyso plasmalogen PC, which suggests an interference of PFCs with membrane lipids. Overall, this work highlights the ability of the PFC mixture to alter cellular lipid pattern at concentrations well below those that generate toxicity, and the potential of the short chain PFBS, often considered a safe substitute of PFOS, to significantly inhibit aromatase activity in placental cells. - Highlights: • Eight perfluorinated chemicals of different chain lengths have been selected. • Long chain ones – PFOS, PFDoA, PFNA, PFOA – were cytotoxic in placenta cells. • The uptake of long chain perfluorinated chemicals by cells was comparatively higher. • PFOS, PFOA and the short chain PFBS significantly inhibited aromatase activity. • A mixture of perfluorinated chemicals significantly altered placenta cell

  17. Cytochrome P450 aromatase expression in human seminoma

    Directory of Open Access Journals (Sweden)

    Montanaro Daniela

    2005-12-01

    Full Text Available Abstract Background The enzyme cytochrome P450 aromatase, catalysing the conversion of androgens into estrogens, has been detected in normal human testicular cells suggesting a physiological role of local estrogen biosynthesis on spermatogenesis control. Estrogens, regulating cell growth and apoptosis, can also be involved in tumorigenesis process, but the possible link between estrogens and testicular neoplastic process is, up to now, scarcely known. This study examined aromatase expression in human seminoma, which is the most common germ cell tumour of the testis. Methods The tumour-bearing testes were obtained from 20 patients with classic seminoma undergoing to therapeutic orchidectomy. Paraffin embedded tissues were processed for immunohistochemistry using a mouse monoclonal antibody generated against human placental cytochrome P450 arom, as primary antibody, and a biotinylated goat-anti-mouse IgG, as secondary antibody. Furthermore, Western blot analysis of seminoma extracts was carried out. Results Intense P450 arom immunoreactivity was observed in the seminoma cells and Western blot analysis confirmed the immunodetection. A strong immunostaining was also detected in cells of intratubular germ cell neoplasia (IGCN, adjacent to seminoma. Conclusion The present study demonstrated, for the first time in human, aromatase expression in neoplastic cells of seminoma suggesting a relation between local estrogen biosynthesis and germ cell tumorigenesis. The P450 arom immunolocalization in the cells of IGCN, representing the common precursor of most germ cell tumors, seems to support these findings.

  18. Bisphenol A affects early bovine embryo development and metabolism that is negated by an oestrogen receptor inhibitor

    Science.gov (United States)

    Choi, Bom-Ie; Harvey, Alexandra J.; Green, Mark P.

    2016-01-01

    Increasing evidence supports an association between exposure to endocrine disruptors, such as the xenoestrogen bisphenol A (BPA), a commonly used plasticiser, and the developmental programming of offspring health. To date however animal studies to investigate a direct causal have mainly focussed on supra-environmental BPA concentrations, without investigating the effect on the early embryo. In this study we investigated the effect of acute BPA exposure (days 3.5 to 7.5 post-fertilisation) at environmentally relevant concentrations (1 and 10 ng/mL) on in vitro bovine embryo development, quality and metabolism. We then examined whether culturing embryos in the presence of the oestrogen receptor inhibitor fulvestrant could negate effects of BPA and 17β-oestradiol (E2). Exposure to BPA or E2 (10 ng/mL) decreased blastocyst rate and the percentage of transferrable quality embryos, without affecting cell number, lineage allocation or metabolic gene expression compared to untreated embryos. Notably, blastocysts exposed to BPA and E2 (10 ng/mL) displayed an increase in glucose consumption. The presence of fulvestrant however negated the adverse developmental and metabolic effects, suggesting BPA elicits its effects via oestrogen-mediated pathways. This study demonstrates that even acute exposure to an environmentally relevant BPA concentration can affect early embryo development and metabolism. These may have long-term health consequences on an individual. PMID:27384909

  19. Synthesis of highly-labeled with tritium steroid hormones and their use for estimation of aromatase activity

    International Nuclear Information System (INIS)

    Highly-labeled steroids - progesterone, estradiol, and androsterone are synthesized. They are used for determination of aromatase activity in different pathologies. It is shown that high activity of aromatase in endometrium in patients with endometrium neoplasms without myome deteriorates disease prognosis. At the same time high aromatase activity in endometrium in patients with endometrium neoplasms with myome has frequently opportune result

  20. Evaluation of a bioluminescent mouse model expressing aromatase PII-promoter-controlled luciferase as a tool for the study of endocrine disrupting chemicals

    International Nuclear Information System (INIS)

    Dysfunction of the enzyme aromatase (CYP19) is associated with endocrine pathologies such as osteoporosis, impaired fertility and development of hormone-dependent cancers. Certain endocrine disrupting chemicals affect aromatase expression and activity in vitro, but little is known about their ability to do so in vivo. We evaluated a bioluminescent mouse model (LPTA (registered) )CD-1-Tg(Cyp19-luc)-Xen) expressing luciferase under control of the gonadal aromatase pII promoter as an in vivo screening tool for chemicals that may affect aromatase expression. We studied the effects of forskolin, pregnant mare serum gonadotropin and atrazine in this model (atrazine was previously shown to induced pII-promoter-driven aromatase expression in H295R human adrenocortical carcinoma cells). About 2-4 out of every group of 10 male or female Cyp19-luc mice injected i.p. with 10 mg/kg forskolin had increased gonadal bioluminescence after 3-5 days compared to controls; the others appeared non-responsive. Similarly, about 4 per group of 9 individual females injected with pregnant mare serum gonadotropin had increased ovarian bioluminescence after 24 h. There was a statistically significant correlation between ovarian bioluminescence and plasma estradiol concentrations (n = 14; p = 0.022). Males exposed to a single dose of 100 mg/kg or males and females exposed to 5 daily injections of 30 mg/kg atrazine showed no change in gonadal bioluminescence over a 7 day period, but a significant interaction was found between atrazine (100 mg/kg) and time in female mice (p < 0.05; two-way ANOVA). Ex vivo luciferase activity in dissected organs was increased by forskolin in testis, epididymis and ovaries. Atrazine (30 mg/kg/day) increased (30%) luciferase activity significantly in epididymis only. In conclusion, certain individual Cyp19-luc mice are highly responsive to aromatase inducers, suggesting this model, with further optimization, may have potential as an in vivo screening tool for

  1. Sex Differences in Brain Aromatase Activity: Genomic and Non-Genomic Controls

    Science.gov (United States)

    Balthazart, Jacques; Charlier, Thierry D.; Cornil, Charlotte A.; Dickens, Molly J.; Harada, Nobuhiro; Konkle, Anne T. M.; Voigt, Cornelia; Ball, Gregory F.

    2011-01-01

    Aromatization of testosterone into estradiol in the preoptic area plays a critical role in the activation of male copulation in quail and in many other vertebrate species. Aromatase expression in quail and in other birds is higher than in rodents and other mammals, which has facilitated the study of the controls and functions of this enzyme. Over relatively long time periods (days to months), brain aromatase activity (AA), and transcription are markedly (four- to sixfold) increased by genomic actions of sex steroids. Initial work indicated that the preoptic AA is higher in males than in females and it was hypothesized that this differential production of estrogen could be a critical factor responsible for the lack of behavioral activation in females. Subsequent studies revealed, however, that this enzymatic sex difference might contribute but is not sufficient to explain the sex difference in behavior. Studies of AA, immunoreactivity, and mRNA concentrations revealed that sex differences observed when measuring enzymatic activity are not necessarily observed when one measures mRNA concentrations. Discrepancies potentially reflect post-translational controls of the enzymatic activity. AA in quail brain homogenates is rapidly inhibited by phosphorylation processes. Similar rapid inhibitions occur in hypothalamic explants maintained in vitro and exposed to agents affecting intracellular calcium concentrations or to glutamate agonists. Rapid changes in AA have also been observed in vivo following sexual interactions or exposure to short-term restraint stress and these rapid changes in estrogen production modulate expression of male sexual behaviors. These data suggest that brain estrogens display most if not all characteristics of neuromodulators if not neurotransmitters. Many questions remain however concerning the mechanisms controlling these rapid changes in estrogen production and their behavioral significance. PMID:22645508

  2. Linking the response of endocrine regulated genes to adverse effects on sex differentiation improves comprehension of aromatase inhibition in a Fish Sexual Development Test.

    Science.gov (United States)

    Muth-Köhne, Elke; Westphal-Settele, Kathi; Brückner, Jasmin; Konradi, Sabine; Schiller, Viktoria; Schäfers, Christoph; Teigeler, Matthias; Fenske, Martina

    2016-07-01

    The Fish Sexual Development Test (FSDT) is a non-reproductive test to assess adverse effects of endocrine disrupting chemicals. With the present study it was intended to evaluate whether gene expression endpoints would serve as predictive markers of endocrine disruption in a FSDT. For proof-of-concept, a FSDT according to the OECD TG 234 was conducted with the non-steroidal aromatase inhibitor fadrozole (test concentrations: 10μg/L, 32μg/L, 100μg/L) using zebrafish (Danio rerio). Gene expression analyses using quantitative RT-PCR were included at 48h, 96h, 28days and 63days post fertilization (hpf, dpf). The selection of genes aimed at finding molecular endpoints which could be directly linked to the adverse apical effects of aromatase inhibition. The most prominent effects of fadrozole exposure on the sexual development of zebrafish were a complete sex ratio shift towards males and an acceleration of gonad maturation already at low fadrozole concentrations (10μg/L). Due to the specific inhibition of the aromatase enzyme (Cyp19) by fadrozole and thus, the conversion of C19-androgens to C18-estrogens, the steroid hormone balance controlling the sex ratio of zebrafish was altered. The resulting key event is the regulation of directly estrogen-responsive genes. Subsequently, gene expression of vitellogenin 1 (vtg1) and of the aromatase cyp19a1b isoform (cyp19a1b), were down-regulated upon fadrozole treatment compared to controls. For example, mRNA levels of vtg1 were down-regulated compared to the controls as early as 48 hpf and 96 hpf. Further regulated genes cumulated in pathways suggested to be controlled by endocrine mechanisms, like the steroid and terpenoid synthesis pathway (e.g. mevalonate (diphospho) decarboxylase (mvd), lanosterol synthase (2,3-oxidosqualene-lanosterol cyclase; lss), methylsterol monooxygenase 1 (sc4mol)) and in lipid transport/metabolic processes (steroidogenic acute regulatory protein (star), apolipoprotein Eb (apoEb)). Taken together

  3. Cognitive and affective changes in mild to moderate Alzheimer's disease patients undergoing switch of cholinesterase inhibitors: a 6-month observational study.

    Directory of Open Access Journals (Sweden)

    Gianfranco Spalletta

    Full Text Available Patients with Alzheimer's disease after an initial response to cholinesterase inhibitors may complain a later lack of efficacy. This, in association with incident neuropsychiatric symptoms, may worsen patient quality of life. Thus, the switch to another cholinesterase inhibitor could represent a valid therapeutic strategy. The aim of this study was to investigate the effectiveness of the switch from one to another cholinesterase inhibitor on cognitive and affective symptoms in mild to moderate Alzheimer disease patients. Four hundred twenty-three subjects were included from the EVOLUTION study, an observational, longitudinal, multicentre study conducted on Alzheimer disease patients who switched to different cholinesterase inhibitor due either to lack/loss of efficacy or response, reduced tolerability or poor compliance. All patients underwent cognitive and neuropsychiatric assessments, carried out before the switch (baseline, and at 3 and 6-month follow-up. A significant effect of the different switch types was found on Mini-Mental State Examination score during time, with best effectiveness on mild Alzheimer's disease patients switching from oral cholinesterase inhibitors to rivastigmine patch. Depressive symptoms, when measured using continuous Neuropsychiatric Inventory values, decreased significantly, while apathy symptoms remained stable over the 6 months after the switch. However, frequency of both depression and apathy, when measured categorically using Neuropsychiatric Inventory cut-off scores, did not change significantly during time. In mild to moderate Alzheimer disease patients with loss of efficacy and tolerability during cholinesterase inhibitor treatment, the switch to another cholinesterase inhibitor may represent an important option for slowing cognitive deterioration. The evidence of apathy stabilization and the positive tendency of depressive symptom improvement should definitively be confirmed in double-blind controlled

  4. Sex Differences in Brain Aromatase Activity: Genomic and Non-Genomic Controls

    OpenAIRE

    JacquesBalthazart; NobuhiroHarada; AnneT.M.Konkle; CornelliaVoigt; GregoryFBall

    2011-01-01

    Aromatization of testosterone into estradiol in the preoptic area plays a critical role in the activation of male copulation in quail and in many other vertebrate species. Aromatase expression in quail and in other birds is higher than in rodents and other mammals, which has facilitated the study of the controls and functions of this enzyme. Over relatively long time periods (days to months), brain aromatase activity and transcription are markedly (4-6 fold) increased by genomic actions of se...

  5. Correlation between aromatase expression in the eutopic endometrium of symptomatic patients and the presence of endometriosis

    Directory of Open Access Journals (Sweden)

    Maia Jr H

    2012-02-01

    Full Text Available Hugo Maia Jr1,2, Clarice Haddad1,2, Julio Casoy11CEPARH, 2Itaigara Memorial Day Hospital, Salvador, Bahia, BrazilObjective: To investigate whether aromatase expression in the eutopic endometrium correlates with the presence and severity of endometriosis in patients with infertility and/or dysmenorrhea undergoing laparoscopy and hysteroscopy.Patients: The study involved 106 patients of reproductive age with symptoms of dysmenorrhea and infertility. Sixteen endometriosis-free asymptomatic patients were used as a control group.Methods: Concomitant laparoscopy and hysteroscopy was carried out in all cases. An endometrial biopsy was taken to determine aromatase p450 expression by immunohistochemistry. Endometriosis was staged according to the American Society of Reproductive Medicine classification.Results: Endometriosis was diagnosed by laparoscopy in 92/106 symptomatic patients. In this group, aromatase expression was detected in the eutopic endometrium of 66/92 patients with endometriosis (72% and in 13/14 (95% patients in the symptomatic, endometriosis-free group (P = 0.09. Aromatase expression was not detected in any patients from the control group. In the endometriosis group, aromatase expression was detected in the eutopic endometrium of 28/45 patients (62% with American Society of Reproductive Medicine classification stage 1 of the disease, in 11/14 patients (78% with stage II, 14/20 patients (70% with stage III, and in 12/13 patients (92% with stage IV; however, the difference was only statistically significant between stages I and IV (P = 0.04.Conclusion: Aromatase expression in the endometrium was associated with the presence of dysmenorrhea and infertility irrespective of the presence of endometriosis. When endometriosis was present, however, there was a tendency for aromatase expression to be positively correlated with dysmenorrhea severity.Keywords: aromatase, endometrium, endometriosis, Cox-2, dysmenorrhea

  6. Constitutional genetic variation at the human aromatase gene (Cyp19) and breast cancer risk

    OpenAIRE

    Siegelmann-Danieli, N; Buetow, K H

    1999-01-01

    The activity of the aromatase enzyme, which converts androgens into oestrogens and has a major role in regulating oestrogen levels in the breast, is thought to be a contributing factor in the development of breast cancer. We undertook this study to assess the role of constitutional genetic variation in the human aromatase gene (Cyp19) in the development of this disease. Our genotyping of 348 cases with breast cancer and 145 controls (all Caucasian women) for a published tetranucleotide repeat...

  7. Effects of aromatase inhibition on spatial working memory and hippocampal astrocyte numbers

    OpenAIRE

    José I. Arias; Héctor González-Pardo; Nélida M. Conejo; Jorge L. Arias

    2012-01-01

    Sex hormones are known to induce the sexual differentiation of the brain during early development in mammals. Testosterone secreted by males already during gestation is classically believed to contribute to brain and behavioural sexual differentiation thanks to its conversion to estradiol by the enzyme aromatase. However, there is evidence suggesting that aromatase inhibition may also impair cognitive functions in women receiving hormonal treatment for breast cancer. In order to evaluate the ...

  8. Overexpression of aromatase alone is sufficient for ovarian development in genetically male chicken embryos.

    Directory of Open Access Journals (Sweden)

    Luke S Lambeth

    Full Text Available Estrogens play a key role in sexual differentiation of both the gonads and external traits in birds. The production of estrogen occurs via a well-characterised steroidogenic pathway, which is a multi-step process involving several enzymes, including cytochrome P450 aromatase. In chicken embryos, the aromatase gene (CYP19A1 is expressed female-specifically from the time of gonadal sex differentiation. To further explore the role of aromatase in sex determination, we ectopically delivered this enzyme using the retroviral vector RCASBP in ovo. Aromatase overexpression in male chicken embryos induced gonadal sex-reversal characterised by an enlargement of the left gonad and development of ovarian structures such as a thickened outer cortex and medulla with lacunae. In addition, the expression of key male gonad developmental genes (DMRT1, SOX9 and Anti-Müllerian hormone (AMH was suppressed, and the distribution of germ cells in sex-reversed males followed the female pattern. The detection of SCP3 protein in late stage sex-reversed male embryonic gonads indicated that these genetically male germ cells had entered meiosis, a process that normally only occurs in female embryonic germ cells. This work shows for the first time that the addition of aromatase into a developing male embryo is sufficient to direct ovarian development, suggesting that male gonads have the complete capacity to develop as ovaries if provided with aromatase.

  9. Post-translational regulation of acid invertase activity by vacuolar invertase inhibitor affects resistance to cold-induced sweetening of potato tubers.

    Science.gov (United States)

    McKenzie, Marian J; Chen, Ronan K Y; Harris, John C; Ashworth, Matthew J; Brummell, David A

    2013-01-01

    Cold-induced sweetening (CIS) is a serious post-harvest problem for potato tubers, which need to be stored cold to prevent sprouting and pathogenesis in order to maintain supply throughout the year. During storage at cold temperatures (below 10 °C), many cultivars accumulate free reducing sugars derived from a breakdown of starch to sucrose that is ultimately cleaved by acid invertase to produce glucose and fructose. When affected tubers are processed by frying or roasting, these reducing sugars react with free asparagine by the Maillard reaction, resulting in unacceptably dark-coloured and bitter-tasting product and generating the probable carcinogen acrylamide as a by-product. We have previously identified a vacuolar invertase inhibitor (INH2) whose expression correlates both with low acid invertase activity and with resistance to CIS. Here we show that, during cold storage, overexpression of the INH2 vacuolar invertase inhibitor gene in CIS-susceptible potato tubers reduced acid invertase activity, the accumulation of reducing sugars and the generation of acrylamide in subsequent fry tests. Conversely, suppression of vacuolar invertase inhibitor expression in a CIS-resistant line increased susceptibility to CIS. The results show that post-translational regulation of acid invertase by the vacuolar invertase inhibitor is an important component of resistance to CIS. PMID:22734927

  10. TISSUE INHIBITOR OF METALLOPROTEINASE 1, MATRIX METALLOPROTEINASE 9, ALPHA-1 ANTITRYPSIN, METALLOTHIONEIN AND UROKINASE TYPE PLASMINOGEN ACTIVATOR RECEPTOR IN SKIN BIOPSIES FROM PATIENTS AFFECTED BY AUTOIMMUNE BLISTERING DISEASES

    Directory of Open Access Journals (Sweden)

    Ana Maria Abreu Velez

    2013-07-01

    Full Text Available Introduction: Proteinases and proteinase inhibitors have been described to play a role in autoimmune skin blistering diseases. We studied skin lesional biopsies from patients affected by several autoimmune skin blistering diseases for proteinases and proteinase inhibitors. Methods: We utilized immunohistochemistry to evaluate biopsies for alpha-1-antitrypsin, human matrix metalloproteinase 9 (MMP9, human tissue inhibitor of metalloproteinases 1 (TIMP-1, metallothionein and urokinase type plasminogen activator receptor (uPAR. We tested 30 patients affected by endemic pemphigus, 30 controls from the endemic area, and 15 normal controls. We also tested 30 biopsies from patients with bullous pemphigoid (BP, 20 with pemphigus vulgaris (PV, 8 with pemphigus foliaceus, and 14 with dermatitis herpetiformis (DH. Results: Contrary to findings in the current literature, most autoimmune skin blistering disease biopsies were negative for uPAR and MMP9. Only some chronic patients with El Bagre-EPF were positive to MMP9 in the dermis, in proximity to telocytes. TIMP-1 and metallothionein were positive in half of the biopsies from BP patients at the basement membrane of the skin, within several skin appendices, in areas of dermal blood vessel inflammation and within dermal mesenchymal-epithelial cell junctions.

  11. The Urease Inhibitor NBPT Negatively Affects DUR3-mediated Uptake and Assimilation of Urea in Maize Roots

    OpenAIRE

    Zanin, Laura; Tomasi, Nicola; Zamboni, Anita; Varanini, Zeno; Pinton, Roberto

    2015-01-01

    Despite the widespread use of urease inhibitors in agriculture, little information is available on their effect on nitrogen (N) uptake and assimilation. Aim of this work was to study, at physiological and transcriptional level, the effects of N-(n-butyl) thiophosphoric triamide (NBPT) on urea nutrition in hydroponically grown maize plants. Presence of NBPT in the nutrient solution limited the capacity of plants to utilize urea as a N-source; this was shown by a decrease in urea uptake rate an...

  12. PARP inhibitor ABT-888 affects response of MDA-MB-231 cells to doxorubicin treatment, targeting Snail expression.

    Science.gov (United States)

    Mariano, Germano; Ricciardi, Maria Rosaria; Trisciuoglio, Daniela; Zampieri, Michele; Ciccarone, Fabio; Guastafierro, Tiziana; Calabrese, Roberta; Valentini, Elisabetta; Tafuri, Agostino; Del Bufalo, Donatella; Caiafa, Paola; Reale, Anna

    2015-06-20

    To overcome cancer cells resistance to pharmacological therapy, the development of new therapeutic approaches becomes urgent. For this purpose, the use of poly(ADP-ribose) polymerase (PARP) inhibitors in combination with other cytotoxic agents could represent an efficacious strategy. Poly(ADP-ribosyl)ation (PARylation) is a post-translational modification that plays a well characterized role in the cellular decisions of life and death. Recent findings indicate that PARP-1 may control the expression of Snail, the master gene of epithelial-mesenchymal transition (EMT). Snail is highly represented in different resistant tumors, functioning as a factor regulating anti-apoptotic programmes. MDA-MB-231 is a Snail-expressing metastatic breast cancer cell line, which exhibits chemoresistance properties when treated with damaging agents. In this study, we show that the PARP inhibitor ABT-888 was capable to modulate the MDA-MB-231 cell response to doxorubicin, leading to an increase in the rate of apoptosis. Our further results indicate that PARP-1 controlled Snail expression at transcriptional level in cells exposed to doxorubicin. Given the increasing interest in the employment of PARP inhibitors as chemotherapeutic adjuvants, our in vitro results suggest that one of the mechanisms through which PARP inhibition can chemosensitize cancer cells in vivo, is targeting Snail expression thus promoting apoptosis. PMID:25938539

  13. Histone Deacetylase Inhibitors Increase p27Kip1 by Affecting Its Ubiquitin-Dependent Degradation through Skp2 Downregulation

    Directory of Open Access Journals (Sweden)

    Adriana Borriello

    2016-01-01

    Full Text Available Histone deacetylase inhibitors (HDACIs represent an intriguing class of pharmacologically active compounds. Currently, some HDACIs are FDA approved for cancer therapy and many others are in clinical trials, showing important clinical activities at well tolerated doses. HDACIs also interfere with the aging process and are involved in the control of inflammation and oxidative stress. In vitro, HDACIs induce different cellular responses including growth arrest, differentiation, and apoptosis. Here, we evaluated the effects of HDACIs on p27Kip1, a key cyclin-dependent kinase inhibitor (CKI. We observed that HDACI-dependent antiproliferative activity is associated with p27Kip1 accumulation due to a reduced protein degradation. p27Kip1 removal requires a preliminary ubiquitination step due to the Skp2-SCF E3 ligase complex. We demonstrated that HDACIs increase p27Kip1 stability through downregulation of Skp2 protein levels. Skp2 decline is only partially due to a reduced Skp2 gene expression. Conversely, the protein decrease is more profound and enduring compared to the changes of Skp2 transcript. This argues for HDACIs effects on Skp2 protein posttranslational modifications and/or on its removal. In summary, we demonstrate that HDACIs increase p27Kip1 by hampering its nuclear ubiquitination/degradation. The findings might be of relevance in the phenotypic effects of these compounds, including their anticancer and aging-modulating activities.

  14. Purification of human placental aromatase cytochrome P-450 with monoclonal antibody and its characterization

    International Nuclear Information System (INIS)

    A simple and efficient method is described for the purification of microsomal aromatase cytochrome P-450 from human placenta. The enzyme was solubilized with Emulgen 913 and sodium cholate and subjected to chromatography on a column of Sepharose 4B couples with a specific monoclonal antibody, followed by hydroxyapatite column chromatography. The specific cytochrome P-450 content of purified aromatase was 13.1 (12-14.8) nmol/mg of protein. Aromatase assays were carried out with reconstituted systems of bovine liver P-450 reductase and dilauroyl-L-α-phosphatidylcholine with [1β-3H,4-14C]androstenedione as substrate. The total recovery of purified aromatase activity was 32.2%, and P-450 recovery was 17.6%. The very high Km value for 16α-hydroxytestosterone aromatization gives a reasonable indication that estriol is not the directly aromatized product in the fetoplacental unit of human pregnancy. The aromatase P-450 was subjected to SDS-polyacrylamide gel electrophoresis in increasing quantities. Silver stain detection techniques indicated a single band having a molecular mass of 55 kDa with greater than 97% purity. The stability analysis showed a half-life of over 4 years on storage at -80C

  15. The tankyrase-specific inhibitor JW74 affects cell cycle progression and induces apoptosis and differentiation in osteosarcoma cell lines

    International Nuclear Information System (INIS)

    Wnt/β-catenin is a major regulator of stem cell self-renewal and differentiation and this signaling pathway is aberrantly activated in a several cancers, including osteosarcoma (OS). Attenuation of Wnt/β-catenin activity by tankyrase inhibitors is an appealing strategy in treatment of OS. The efficacy of the tankyrase inhibitor JW74 was evaluated in three OS cell lines (KPD, U2OS, and SaOS-2) both at the molecular and functional level. At the molecular level, JW74 induces stabilization of AXIN2, a key component of the β-catenin destruction complex, resulting in reduced levels of nuclear β-catenin. At the functional level, JW74 induces reduced cell growth in all three tested cell lines, in part due to a delay in cell cycle progression and in part due to an induction of caspase-3-mediated apoptosis. Furthermore, JW74 induces differentiation in U2OS cells, which under standard conditions are resistant to osteogenic differentiation. JW74 also enhances differentiation of OS cell lines, which do not harbor a differentiation block. Interestingly, microRNAs (miRNAs) of the let-7 family, which are known tumor suppressors and inducers of differentiation, are significantly upregulated following treatment with JW74. We demonstrate for the first time that tankyrase inhibition triggers reduced cell growth and differentiation of OS cells. This may in part be due to an induction of let-7 miRNA. The presented data open for novel therapeutic strategies in the treatment of malignant OS

  16. Are separable aromatase systems involved in hormonal regulation of the male brain

    International Nuclear Information System (INIS)

    In vitro study of testosterone (T) metabolism shows that formation of estradiol-17 beta (E2) is regionally specific within the preoptic area (POA) of the male ring dove. The POA is known to be involved in the formation of E2 required for specific components of male sexual behavior. Two sub-areas of high aromatase activity, anterior (aPOA) and posterior preoptic (pPOA) areas, have been identified. Aromatase activity is higher in aPOA than in pPOA. The aromatase activity within the aPOA is also more sensitive to the inductive effects of low circulating T, derived from subcutaneous silastic implants, than the enzyme activity in pPOA. Kinetic analysis of preoptic fractions indicates that a similar high-affinity enzyme occurs in both areas (apparent Km less than 14 nM), but the Vmax of aPOA enzyme activity is higher than pPOA. Cells containing estrogen receptors (ER) are localized in areas of high aromatase activity. There is overlap between immunostained cells in the aPOA and in samples containing inducible aromatase activity measured in vitro. Within the aPOA there is a higher density of ER cells in the nucleus preopticus medialis. The pPOA area also contains ER, notably in the nucleus interstitialis, but at a lower density. We conclude that the hormonal regulation of the male preoptic-anterior hypothalamic region, which is a target for the behavioral action of T, involves at least two inducible aromatase systems with associated estrogen receptor cells

  17. Are separable aromatase systems involved in hormonal regulation of the male brain

    Energy Technology Data Exchange (ETDEWEB)

    Hutchison, J.B.; Schumacher, M.; Steimer, T.; Gahr, M. (Institute of Animal Physiology, Babraham, Cambridge (England))

    1990-07-01

    In vitro study of testosterone (T) metabolism shows that formation of estradiol-17 beta (E2) is regionally specific within the preoptic area (POA) of the male ring dove. The POA is known to be involved in the formation of E2 required for specific components of male sexual behavior. Two sub-areas of high aromatase activity, anterior (aPOA) and posterior preoptic (pPOA) areas, have been identified. Aromatase activity is higher in aPOA than in pPOA. The aromatase activity within the aPOA is also more sensitive to the inductive effects of low circulating T, derived from subcutaneous silastic implants, than the enzyme activity in pPOA. Kinetic analysis of preoptic fractions indicates that a similar high-affinity enzyme occurs in both areas (apparent Km less than 14 nM), but the Vmax of aPOA enzyme activity is higher than pPOA. Cells containing estrogen receptors (ER) are localized in areas of high aromatase activity. There is overlap between immunostained cells in the aPOA and in samples containing inducible aromatase activity measured in vitro. Within the aPOA there is a higher density of ER cells in the nucleus preopticus medialis. The pPOA area also contains ER, notably in the nucleus interstitialis, but at a lower density. We conclude that the hormonal regulation of the male preoptic-anterior hypothalamic region, which is a target for the behavioral action of T, involves at least two inducible aromatase systems with associated estrogen receptor cells.

  18. Xanthones from the Botanical Dietary Supplement Mangosteen (Garcinia mangostana) with Aromatase Inhibitory Activity

    OpenAIRE

    Balunas, Marcy J.; Su, Bin; Brueggemeier, Robert W.; Kinghorn, A. Douglas

    2008-01-01

    Twelve xanthone constituents of the botanical dietary supplement, mangosteen (the pericarp of Garcinia mangostina) were screened using a non-cellular, enzyme-based microsomal aromatase inhibition assay. Of these compounds, garcinone D (3), garcinone E (5)α-mangostin (8), and γ-mangostin (9) exhibited dose-dependent inhibitory activity. In a follow-up cell-based assay using SK-BR-3 breast cancer cells that express high levels of aromatase, the most potent of these four xanthones was γ-mangosti...

  19. Environmental factors affecting the corrosion behaviour of reinforcing steel. VI. Benzotriazole and its derivatives as corrosion inhibitors of steel

    International Nuclear Information System (INIS)

    Highlights: • The rate of oxide film repair follows a direct logarithmic law. • The inhibition efficiency depend on Cl− and the organic additives concentrations. • Benzotriazoles inhibit pitting corrosion by way of adsorption. • ΔG°ads values for organic additives reveal a chemisorption mechanism. - Abstract: Benzotriazole and some of its derivatives cause inhibition of corrosion of reinforcing steel in saturated naturally aerated Ca(OH)2 solutions contaminated by Cl−. The inhibition efficiency of these compounds depends on both the inhibitor type and concentration, as well as, on the chloride ions content. Inhibition by these compounds is assumed to take place through the formation of iron-chloro-benzotriazoles complexes and/or the adsorption of the deprotonated species on the steel surface according to Langmuir’s isotherm. The thermodynamic parameters Kads and ΔG°ads for the adsorption process are calculated and discussed. Benzotriazoles shift the pitting corrosion potential into the noble direction accounting for increased resistance to pitting

  20. The juxtamembrane sequence of the Hepatitis C virus polymerase can affect RNA synthesis and inhibition by allosteric polymerase inhibitors.

    Science.gov (United States)

    Wen, Y; Lin, X; Fan, B; Ranjith-Kumar, C T; Kao, C C

    2015-08-01

    The Hepatitis C virus (HCV) RNA-dependent RNA polymerase (RdRp), nonstructural protein 5B (NS5B), is anchored in the membrane through a C-terminal helix. A sequence of ca. 12 residues that connects the catalytically competent portion of the RdRp and the C-terminal helix, the juxtamembrane sequence (JMS), has a poorly defined role in RdRp function in a large part since it is translated from a cis-acting RNA element (CRE) that is essential for HCV replication. Using a HCV replicon that transposed a second copy of CRE to the 3' UTR of the HCV replicon, we demonstrate that amino acid substitutions in the JMS were detrimental for HCV replicon replication. Substitutions in the JMS also resulted in a defect in de novo-initiated RNAs synthesis in vitro and in a cell-based reporter assay. A nonnucleoside inhibitor of the NS5B that binds to the catalytic pocket was less potent in inhibiting NS5B in the presence of JMS mutations. The JMS mutants exhibit reduced stability in thermodenaturation assays, suggesting that the JMS helps confer a more stable conformation to NS5B that could impact RNA synthesis. PMID:25895103

  1. A Case of Erythrocytosis in a Patient Treated with an Aromatase Inhibitor for Breast Cancer

    OpenAIRE

    Abhinav Iyengar; Dawn Sheppard

    2013-01-01

    A previously healthy 79-year-old female was referred to hematology for further evaluation of erythrocytosis. Two years earlier she had been diagnosed with ER/PR-positive ductal carcinoma of the breast and was receiving hormonal therapy with exemestane. No secondary cause of erythrocytosis was identified. Serum erythropoietin (EPO) level was normal, and molecular testing for the JAK2 V617F and exon 12 mutations was negative. A bone marrow biopsy showed a mild increase in erythropoiesis, and no...

  2. Sensitivity of New Zealand mudsnail Potamopyrgus antipodarum (Gray) to a specific aromatase inhibitor

    OpenAIRE

    M. Gust; Garric, J.; Giamberini, L.; Mons, R.; Abbaci, K.; Garnier, F; Buronfosse, T.

    2010-01-01

    The freshwater prosobranch Potamopyrgus antipodarum (Molluska, Hydrobiidea, Smith 1889) has been proposed as a suitable species to assess the impact of endocrine disrupting compounds (EDC) in aquatic ecosystems. Steroid hormone biosynthesis pathway is potentially an important target for EDC, and vertebrate-like sex steroids seem to play a functional role in the control of mollusk reproduction. To assess the response and the sensitivity of P. antipodarum to disrupters of the steroid hormone bi...

  3. Aromatase inhibitor-associated bone loss and its management with bisphosphonates in patients with breast cancer

    OpenAIRE

    Bauer M; Bryce J; Hadji P

    2012-01-01

    M Bauer,1 J Bryce,2 P Hadji11University of Marburg, Marburg, Germany; 2National Cancer Institute, Naples, ItalyAbstract: Postmenopausal women have an increased risk of osteopenia and osteoporosis due to loss of the bone-protective effects of estrogen. Disease-related processes may also contribute to the risk of bone loss in postmenopausal women with breast cancer. One of the most common and severe safety issues associated with cancer therapy for patients with breast cancer is bone loss and th...

  4. Postulated vasoactive neuropeptide immunopathology affecting the blood–brain/blood–spinal barrier in certain neuropsychiatric fatigue-related conditions: A role for phosphodiesterase inhibitors in treatment?

    Directory of Open Access Journals (Sweden)

    Sonya Marshall-Gradisnik

    2008-10-01

    contribute to the BBB and BSB integrity and contain PACAP and VIP receptors. Autoimmunity of these receptors would likely affect BBB and VRS function and therefore may contribute to the etiology of these conditions by affecting CNS and immunological homeostasis, including promoting neuropsychological symptomatology. PACAP and VIP, as potent activators of adenylate cyclase (AC, have a key role in cyclic adenosine monophosphate (cAMP production affecting regulatory T cell (Treg and other immune functions. Phosphodiesterase enzymes (PDEs catalyze cAMP and PDE inhibitors (PDEIs maintain cAMP levels and have proven and well known therapeutic benefit in animal models such as experimental allergic encephalomyelitis (EAE. Therefore PDEIs may have a role in therapy for certain neuropsychiatric fatigue-related conditions.Keywords: vasoactive neuropeptides, multiple sclerosis, Parkinson’s disease, chronic fatigue syndrome, phosphodiesterase inhibitors, cyclic AMP, adenylate cyclase, Virchow–Robin spaces

  5. Vascular endothelial growth inhibitor affects the invasion, apoptosis and vascularisation in breast cancer cell line MDA-MB-231

    Institute of Scientific and Technical Information of China (English)

    Gao Yinguang; Ge Zhicheng; Zhang Zhongtao; Bai Zhigang; Ma Xuemei; Wang Yu

    2014-01-01

    Background Breast cancer is one of the most common malignant female diseases worldwide.It is a significant threat to every woman's health.Vascular endothelial growth inhibitor (VEGI) is known to be abundant in endothelial cells.According to previous literature,overexpression of VEGI has been shown to inhibit tumor neovascularisation and progression in cellular and animal models,but there has been limited research on the significance of VEGI in the breast cancer.Methods In our study,cell lines MDA-MB-231 were first constructed in which VEGI mediated by lentivirus over-expressed.The effects of VEGI over-expression on MDA-MB-231 cells were investigated both in vitro and in vivo.The expression of VEGI in the MDA-MB-231 cells after infection of lentivirus was analyzed using real-time PCR and Western blotting.The effect of the biological characteristics of MDA-MB-231 cells was assessed by growth,invasion,adhesion,and migration assay with subcutaneous tumor-bearing nude mice models.Then the growth curves of the subcutaneous tumors were studied.Expressions of VEGI,CD31 and CD34 in the tumors were analyzed by immunohistochemistry and apoptosis was detected by flow cytometry and immunohistochemistry.Results Infection of MDA-MB-231 cells within the lentivirus resulted in approximately a 1 000-fold increase in the expression of VEGI.As can be seen in the invasion,adhesion and migration assay,the over-expression of VEGI can inhibit the ability of MDA-MB-231 cells during migration,adhesion and invasion.The volume of the subcutaneous tumor in the over-expression group was distinctly and significantly less than that of the control groups.Immunohistochemistry analysis of the tumor biopsies cleady showed the expression of VEGI in the over-expression group increased while CD31 and CD34 decreased significantly.In vitro and in vivo,the early apoptosis rate and the apoptosis index were increased within the VEGI over-expression group as compared with the control group.Conclusions Taken

  6. Profile of Steroid Receptors and Increased Aromatase Immunoexpression in Canine Inflammatory Mammary Cancer as a Potential Therapeutic Target.

    Science.gov (United States)

    De Andrés, P J; Cáceres, S; Clemente, M; Pérez-Alenza, M D; Illera, J C; Peña, L

    2016-04-01

    Canine inflammatory mammary cancer (IMC) has been proposed as a model for the study of human inflammatory breast cancer (IBC). The aims of this study were to compare the immunohistochemical expression of aromatase (Arom) and several hormone receptors [estrogen receptor α (ERα), estrogen receptor β (ERβ), progesterone receptor (PR) and androgen receptor (AR)], in 21 IMC cases vs 19 non-IMC; and to study the possible effect of letrozole on canine IMC and human inflammatory breast cancer (IBC) in vitro using IPC-366 and SUM-149 cell lines. Significant elevations of the means of Arom Total Score (TS), ERβ TS and PR TS were found in the IMC group (p = 0.025, p = 0.038 and p = 0.037, respectively). Secondary IMC tumours expressed higher levels of Arom than primary IMC (p = 0.029). Non-IMC PR- tumours contained higher levels of Arom than non-IMC PR+ tumours (p = 0.007). After the addition of letrozole, the number of IMC and IBC cells dropped drastically. The overexpression of Arom found and the results obtained in vitro further support canine IMC as a model for the study of IBC and future approaches to the treatment of dogs with mammary cancer, and especially IMC, using Arom inhibitors. PMID:26899138

  7. Potential contribution of aromatase inhibition to the effects of nicotine and related compounds on the brain

    Directory of Open Access Journals (Sweden)

    Anat Biegon

    2012-11-01

    Full Text Available Cigarette smoking continues to be a major public health problem, and while smoking rates in men have shown some decrease over the last few decades, smoking rates among girls and young women are increasing. Practically all of the important aspects of cigarette smoking are sexually dimorphic. Women become addicted more easily than men, while finding it harder to quit. Nicotine replacement appears to be less effective in women. This may be linked to the observation that women are more sensitive than men to non-nicotine cues or ingredients in cigarettes. The reasons for these sex differences are mostly unknown. Several lines of evidence suggest that many of the reported sex differences related to cigarette smoking may stem from the inhibitory effects of nicotine and other tobacco alkaloids on estrogen synthesis via the enzyme aromatase (cyp19a gene product. Aromatase is the last enzyme in estrogen biosynthesis, catalyzing the conversion of androgens to estrogens. This review provides a summary of experimental evidence supporting brain aromatase as a potential mediator and/or modulator of nicotine actions in the brain, contributing to sex differences in smoking behavior. Additional research on the interaction between tobacco smoke, nicotine and aromatase may help devise new, sex specific methods for prevention and treatment of smoking addiction.

  8. Expression Patterns of Cytochrome P450 Aromatase Genes During Ovary Development and Their Responses to Temperature Stress in Female Yellow Catfish (Pelteobagrus fulvidraco)

    Institute of Scientific and Technical Information of China (English)

    LIU Miao; QI Baoxia; WEN Haishen; HE Feng; LI Jifang; SHI Dan; HU Jian; ZHANG Yuanqing; MA Ruiqin; MU Weijie

    2011-01-01

    Cytochrome P450 aromatase (P450arom) plays a pivotal role in ovary development.In this study,we used semi-quantitative reverse transcription PCR (RT-PCR) to analyze spatiotemporal expressions of two P450arom genes (CYP1gA and CYP19B)and their responses to temperature stress in female yellow catfish (Pelteobagrusfulvidraco).Tissue distribution pattern of CYP19showed that CYP19B was abundantly expressed in fish brain and ovary (brain>ovary),but weakly in intestines,whereas CYP19Awas exclusively expressed in ovary.Semi-quantitative RT-PCR analyses showed high transcript abundance of both CYP19A and CYP19B in the ovarian reproductive cycle,corresponding with serum estradiol-17β (E2) levels.Increases in aromatases,serum E2 and testosterone (T) levels in fish exposed to higher temperature indicated stimulation of ovarian maturation and recrudescence by heat stress in stages Ⅱ and V during the ovarian cycle,whereas associated decreases in stage III suggested vitellogenesis inhibition by heat stress.Gene expression of CYP19 was closely related to levels of serum E2.Results demonstrated CYP19 played a crucial role in the reproductive cycle of female yellow catfish.Different temperature stress affected CYP19 gene expression in the fish ovarian reproductive cycle.Associated P450arom genes could be useful for studying physiological aspects of yellow catfish.

  9. EFFECTS OF INCUBATION TEMPERATURE AND ESTROGEN EXPOSURE ON AROMATASE ACTIVITY IN THE BRAIN AND GONADS OF EMBRYONIC ALLIGATORS

    Science.gov (United States)

    During embryogenesis, incubation temperature and the hormonal environment influence gonadal differentiation of some reptiles, including all crocodilians. Current evidence suggests that aromatase, the enzyme that converts androgens to estrogens, has a role in sexual differentiatio...

  10. Effects of Pharmaceuticals Used for Breast Cancer Treatment on Reproduction and Aromatase Activity in a Marine Fish

    Science.gov (United States)

    Laboratory experiments were conducted with the marine fish cunner (Tautogolabrus adspersus) to evaluate whether four pharmaceuticals used in breast cancer treatment have an impact on reproduction or aromatase activity. Tamoxifen binds to estrogen receptors, while anastrozole, let...

  11. Post-proliferative immature radial glial cells female-specifically express aromatase in the medaka optic tectum.

    Directory of Open Access Journals (Sweden)

    Akio Takeuchi

    Full Text Available Aromatase, the key enzyme responsible for estrogen biosynthesis, is present in the brain of all vertebrates. Much evidence has accumulated that aromatase is highly and exclusively expressed in proliferating mature radial glial cells in the brain of teleost fish even in adulthood, unlike in other vertebrates. However, the physiological significance of this expression remains unknown. We recently found that aromatase is female-specifically expressed in the optic tectum of adult medaka fish. In the present study, we demonstrated that, contrary to the accepted view of the teleost brain, female-specific aromatase-expressing cells in the medaka optic tectum represent a transient subset of post-proliferative immature radial glial cells in the neural stem cell lineage. This finding led us to hypothesize that female-specific aromatase expression and consequent estrogen production causes some sex difference in the life cycle of tectal cells. As expected, the female tectum exhibited higher expression of genes indicative of cell proliferation and radial glial maturation and lower expression of an anti-apoptotic gene than did the male tectum, suggesting a female-biased acceleration of the cell life cycle. Complicating the interpretation of this result, however, is the additional observation that estrogen administration masculinized the expression of these genes in the optic tectum, while simultaneously stimulating aromatase expression. Taken together, these results provide evidence that a unique subpopulation of neural stem cells female-specifically express aromatase in the optic tectum and suggest that this aromatase expression and resultant estrogen synthesis have an impact on the life cycle of tectal cells, whether stimulatory or inhibitory.

  12. Immunocytochemical and biochemical evidence for aromatase in neurons of the retina, optic tectum and retinotectal pathways in goldfish.

    Science.gov (United States)

    Gelinas, D; Callard, G V

    1993-12-01

    Using an animal model in which neural aromatase is apparently overexpressed (the goldfish, Carassius auratus) and an anti-human placental antibody which specifically crossreacts with goldfish brain aromatase, aromatase-immunoreactive neuronal cell bodies and fibers have been localized within the retina. These include a subset of horizontal cells, bipolar cells, and amacrine cells of the inner nuclear layer, some fibers of the outer and inner synaptic layers and certain cells of the ganglion cell layer; photoreceptors were never labeled. Some ganglion cell projections to the brain via the optic nerve and optic tract were aromatase-positive, as were small neurons of the stratum periventriculare (SPV) and fibers of two other strata of the optic tectum. Aromatase activity, as measured by [3H]androgen by tissue homogenates and cell cultures, confirmed the presence of aromatase in retina and in brain regions containing the optic tectum. This localization of the rate-limiting enzyme in estrogen biosynthesis suggests that neuroestrogen derived from circulating androgen m ay modulate transmission and integration of visual information important for reproduction in this species. PMID:8680435

  13. In situ aromatase expression in primary tumor is associated with estrogen receptor expression but is not predictive of response to endocrine therapy in advanced breast cancer

    DEFF Research Database (Denmark)

    Lykkesfeldt, Anne E; Henriksen, Katrine L; Rasmussen, Birgitte B;

    2009-01-01

    Wilcoxon analysis and the Cox-analysis were performed to evaluate time to progression (TTP) in relation to marker expression. RESULTS: Aromatase expression was associated with ER, but not with PR or COX-2 expression in carcinoma cells. Measurements of aromatase in WS were not comparable to results from...... TMAs. Expression of COX-2 and aromatase did not predict response to endocrine therapy. Aromatase in combination with high PR expression may select letrozole treated patients with a longer TTP. CONCLUSION: TMAs are not suitable for IHC analysis of in situ aromatase expression and we did not find COX-2...... estrogen synthesis may not be the major source of intratumoral estrogen. However, aromatase expression in combination with high PR expression may select letrozole treated patients with longer TTP. TRIAL REGISTRATION: Sub-study of trial P025 for advanced breast cancer....

  14. TRIM5α and TRIMCyp form apparent hexamers and their multimeric state is not affected by exposure to restriction-sensitive viruses or by treatment with pharmacological inhibitors

    Directory of Open Access Journals (Sweden)

    Berthoux Lionel

    2009-11-01

    Full Text Available Abstract Proteins of the TRIM5 family, such as TRIM5α and the related TRIMCyp, are cytoplasmic factors that can inhibit incoming retroviruses. This type of restriction requires a direct interaction between TRIM5 proteins and capsid proteins that are part of mature, intact retroviral cores. In such cores, capsids are arranged as hexameric units. Multiple lines of evidence imply that TRIM5 proteins themselves interact with retroviral cores as multimers. Accordingly, stabilization by crosslinking agents has revealed that TRIM5α and TRIMCyp are present as trimers in mammalian cells. We report here that TRIM5 proteins seem to form dimers, trimers, hexamers and multimers of higher complexity in mammalian cells. The hexameric form in particular seems to be the most abundant multimer. Multimerization did not involve disulfide bridges and was not affected by infection with restriction-sensitive viruses or by treatment with the known TRIM5 inhibitors arsenic trioxide, MG132 and cyclosporine A. We conclude that TRIM5 multimerization results from more than one protein-protein interface and that it is seemingly not triggered by contact with retroviral cores.

  15. Effects of currently used pesticides in assays for estrogenicity, androgenicity, and aromatase activity in vitro

    DEFF Research Database (Denmark)

    Andersen, Helle Raun; Vinggaard, Anne; Rasmussen, Thomas Høj;

    2002-01-01

    Twenty-four pesticides were tested for interactions with the estrogen receptor (ER) and the androgen receptor (AR) in transactivation assays. Estrogen-like effects on MCF-7 cell proliferation and effects on CYP19 aromatase activity in human placental microsomes were also investigated. Pesticides ...... to the natural ligands, the integrated response in the organism might be amplified by the ability of the pesticides to act via several mechanism and the frequent simultaneous exposure to several pesticides.......Twenty-four pesticides were tested for interactions with the estrogen receptor (ER) and the androgen receptor (AR) in transactivation assays. Estrogen-like effects on MCF-7 cell proliferation and effects on CYP19 aromatase activity in human placental microsomes were also investigated. Pesticides...... to their frequent use in Danish greenhouses. In addition, the metabolite mercaptodimethur sulfoxide, the herbicide tribenuron-methyl, and the organochlorine dieldrin, were included. Several of the pesticides, dieldrin, endosulfan, methiocarb, and fenarimol, acted both as estrogen agonists and...

  16. Ligula intestinalis infection is associated with alterations of both brain and gonad aromatase expression in roach (Rutilus rutilus).

    Science.gov (United States)

    Boulange-Lecomte, C; Geraudie, P; Forget-Leray, J; Gerbron, M; Minier, C

    2011-09-01

    The tapeworm Ligula intestinalis commonly infests roach (Rutilus rutilus) and is responsible for the inhibition of gonad development. In order to better understand the effect of the plerocercoid on fish physiology, and to discriminate parasitization effects from those of endocrine-disrupting compounds (EDC), Cyp19b and Cyp19a aromatase expression was investigated by real-time quantitative polymerase chain reaction (PCR) in brain and gonads of ligulosed roach, caught from a reference site. Data were compared to reproductive and endocrine endpoints previously reported in a larger cohort study (including the sampled population of the present one), such as gonadosomatic index, Fulton index, gonadal histology, plasma sex steroid levels and brain aromatase activity. A decrease in Cyp19b expression in the brain of infected fish was demonstrated, in agreement with the reduction of aromatase activity previously described. In contrast, Cyp19a expression in the gonads appeared to be enhanced in ligulosed fish, in accordance with the presence of immature but differentiated sexual tissues. Together these results show that: (1) L. intestinalis infestation results in an alteration of aromatase expression which, in particular, may have profound effects on the fish brain; and (2) L. intestinalis infection must be considered as a major confounding factor in ecotoxicological studies using aromatase expression as an EDC biomarker. Moreover, the concordance between activity and expression--investigated for the first time in the same population--gives a functional relevance to the transcript aromatase dosage in the brain. Finally, quantitative PCR was confirmed as a sensitive approach, enabling aromatase status to be defined in the poorly developed gonads of ligulosed individuals. PMID:21062527

  17. Inhibition of human placental aromatase activity by hydroxylated polybrominated diphenyl ethers (OH-PBDEs)

    International Nuclear Information System (INIS)

    Polybrominated diphenyl ethers (PBDEs) are widely used as flame retardants in many different polymers, resins and substrates. Due to their widespread production and use, their high binding affinity to particles, and their lipophilic properties, several PBDE congeners can bioaccumulate in the environment. As a result, PBDEs and their hydroxylated metabolites (OH-PBDEs) have been detected in humans and various wildlife samples, such as birds, seals, and whales. Furthermore, certain OH-PBDEs and their methoxylated derivatives (MeO-PBDEs) are natural products in the marine environment. Recently, our laboratory focused on the possible effects on steroidogenesis of PBDEs and OH-PBDEs, e.g. in the human adrenocortical carcinoma (H295R) cell line indicating that some OH-PBDEs can significantly influence steroidogenic enzymes like CYP19 (aromatase) and CYP17. In the present study, human placental microsomes have been used to study the possible interaction of twenty two OH-PBDEs and MeO-PBDEs with aromatase, the enzyme that mediates the conversion of androgens into estrogens. All OH-PBDE derivates showed significant inhibition of placental aromatase activity with IC50 values in the low micromolar range, while the MeO-PBDEs did not have any effect on this enzyme activity. Enzyme kinetics studies indicated that two OH-PBDEs, 5-hydroxy-2,2',4,4'-tetrabromodiphenyl ether (5-OH-BDE47) and 6-hydroxy-2,2',4,4'-tetrabromodiphenyl ether (6-OH-BDE47), had a mixed-type inhibition of aromatase activity with apparent Ki/Ki' of 7.68/0,02 μM and 5.01/0.04 μM respectively. For comparison, some structurally related compounds, a dihydroxylated polybrominated biphenyl, which is a natural product (2,2'-dihyroxy-3,3',5,5'-tetrabromobiphenyl (2,2'-diOH-BB80)) and its non-bromo derivative were also included in the study. Again inhibition of aromatase activity could be measured, but their potency was significantly less than those observed for the OH-PBDEs. These results show that a wide range of

  18. Factors affecting the corrosion behaviour of aluminium in acid solutions. I. Nitrogen and/or sulphur-containing organic compounds as corrosion inhibitors for Al in HCl solutions

    International Nuclear Information System (INIS)

    Highlights: ► Phenylhydrazine, urea, thiourea, N-allylthiourea, and thiosemicarbazide are good inhibitors for corrosion Al in HCl. ► The additives decrease the rate of corrosion by the adsorption process. ► ΔGads of all used inhibitors reveal strong physisorption process. - Abstract: The corrosion behaviour of Al in 2 M HCl solution in the absence and presence of phenylhydrazine, urea, thiourea, N-allylthiourea, and thiosemicarbazide is investigated using different chemical and electrochemical techniques. The inhibition efficiencies of these compounds increase with increasing their concentration and molecular weights. The inhibitive action of these compounds is discussed in terms of blocking the electrode surface by adsorption of the inhibitor molecules according to Langmuir isotherm. The thermodynamic parameters Kads and ΔGads° are calculated and discussed. The values of ΔGads° reveal strong physisorption of the inhibitors on the metal surface.

  19. Brain aromatase (Cyp19A2) and estrogen receptors, in larvae and adult pejerrey fish Odontesthes bonariensis: Neuroanatomical and functional relations

    Science.gov (United States)

    Strobl-Mazzulla, P. H.; Lethimonier, C.; Gueguen, M.M.; Karube, M.; Fernandino, J.I.; Yoshizaki, G.; Patino, R.; Strussmann, C.A.; Kah, O.; Somoza, G.M.

    2008-01-01

    Although estrogens exert many functions on vertebrate brains, there is little information on the relationship between brain aromatase and estrogen receptors. Here, we report the cloning and characterization of two estrogen receptors, ?? and ??, in pejerrey. Both receptors' mRNAs largely overlap and were predominantly expressed in the brain, pituitary, liver, and gonads. Also brain aromatase and estrogen receptors were up-regulated in the brain of estradiol-treated males. In situ hybridization was performed to study in more detail, the distribution of the two receptors in comparison with brain aromatase mRNA in the brain of adult pejerrey. The estrogen receptors' mRNAs exhibited distinct but partially overlapping patterns of expression in the preoptic area and the mediobasal hypothalamus, as well as in the pituitary gland. Moreover, the estrogen receptor ??, but not ??, were found to be expressed in cells lining the preoptic recess, similarly as observed for brain aromatase. Finally, it was shown that the onset expression of brain aromatase and both estrogen receptors in the head of larvae preceded the morphological differentiation of the gonads. Because pejerrey sex differentiation is strongly influenced by temperature, brain aromatase expression was measured during the temperature-sensitive window and was found to be significantly higher at male-promoting temperature. Taken together these results suggest close neuroanatomical and functional relationships between brain aromatase and estrogen receptors, probably involved in the sexual differentiation of the brain and raising interesting questions on the origin (central or peripheral) of the brain aromatase substrate. ?? 2008 Elsevier Inc.

  20. Sex chromosome complement determines sex differences in aromatase expression and regulation in the stria terminalis and anterior amygdala of the developing mouse brain.

    Science.gov (United States)

    Cisternas, Carla D; Tome, Karina; Caeiro, Ximena E; Dadam, Florencia M; Garcia-Segura, Luis M; Cambiasso, María J

    2015-10-15

    Aromatase, which converts testosterone in estradiol, is involved in the generation of brain sex dimorphisms. Here we used the "four core genotypes" mouse model, in which the effect of gonadal sex and sex chromosome complement is dissociated, to determine if sex chromosomes influence the expression of brain aromatase. The brain of 16 days old XY mouse embryos showed higher aromatase expression in the stria terminalis and the anterior amygdaloid area than the brain of XX embryos, independent of gonadal sex. Furthermore, estradiol or dihydrotestosterone increased aromatase expression in cultures of anterior amygdala neurons derived from XX embryos, but not in those derived from XY embryos. This effect was also independent of gonadal sex. The expression of other steroidogenic molecules, estrogen receptor-α and androgen receptor was not influenced by sex chromosomes. In conclusion, sex chromosomes determine sex dimorphisms in aromatase expression and regulation in the developing mouse brain. PMID:26231585

  1. Quantitative determination, by real-time reverse transcription polymerase chain reaction, of aromatase mRNA in invasive ductal carcinoma of the breast

    International Nuclear Information System (INIS)

    Estrogen is a mitogenic factor that is implicated in the genesis and progression of breast cancer via its binding to estrogen receptor (ER)-α. Synthesis of estrogen in situ is believed to be catalyzed mainly by aromatase. Previous studies comparing the relative contributions from tumor cells and stromal cells to local estrogen synthesis, as assessed by immunohistochemical analysis, were quite controversial and no consistent relationship was found between the presence of aromatase and any clinicopathologic factor. In addition, previous studies into aromatase gene expression and clinicopathologic factors are limited. We assessed the level of expression of aromatase mRNA, using quantitative real-time RT-PCR, in 162 cases of invasive ductal carcinoma of the breast. Associations between aromatase expression and different clinicopathologic factors were sought. It was found that aromatase mRNA was expressed at significantly higher levels in patients older than 50 years, in those without axillary lymph node involvement, in those with tumor size less than 2 cm, and in ER-α positive tumors. However, no relationship was found between aromatase mRNA expression and any other clinicopathologic factor, including histologic grade and progesterone receptor status. Patients with high levels of expression of aromatase mRNA tended to have a better prognosis than did those patients with low expression. These findings imply that ER-α and aromatase may be coexpressed in endocrine responsive patients. They may also indicate that aromatase expression could be a marker of endocrine responsiveness, and it may have prognostic implications for breast cancer progression

  2. Plasma concentrations of estradiol and testosterone, gonadal aromatase activity and ultrastructure of the testis in Xenopus laevis exposed to estradiol or atrazine

    International Nuclear Information System (INIS)

    The ultrastructure of testicular cells of adult male African clawed frogs (Xenopus laevis) exposed to either estradiol (0.1 μg/L) or 2-chloro-4-ethylamino-6-isopropyl-amino-s-triazine (atrazine; 10 or 100 μg/L) was examined by electron microscopy and compared to plasma concentrations of the steroid hormones, testosterone (T) and estradiol (E2), testicular aromatase activity and gonad growth expressed as the gonado-somatic index (GSI). Exposure to E2 caused significant changes both at the sub-cellular and biochemical levels. Exposure to E2 resulted in significantly fewer sperm cells, inhibition of meiotic division of germ cells, more lipid droplets that are storage compartments for the sex steroid hormone precursor cholesterol, and lesser plasma T concentrations. Although not statistically significant, frogs exposed to E2 had slightly smaller GSI values. These results may be indicative of an inhibition of gonad growth and disrupted germ cell development by E2. Concentrations of E2 in plasma were greater in frogs exposed to E2 in water. Exposure to neither concentration of atrazine caused effects on germ cell development, testicular aromatase activity or plasma hormone concentrations. These results suggest that atrazine does not affect testicular function. In contrast, exposure of male X. laevis to E2 led to sub-cellular events that are indicative of disruption of testicular development, and demasculinization processes (decrease of androgen hormone titers). These results indicate that atrazine does not cause responses that are similar to those caused by exposure to E2

  3. Effects of Nutrition Relevant Mixtures of Phytoestrogens on Steroidogenesis, Aromatase, Estrogen, and Androgen Activity

    DEFF Research Database (Denmark)

    Taxvig, Camilla; Engell-Kofoed, Anders Elleby; Sonne-Hansen, Katrine;

    2010-01-01

    Phytoestrogens (PEs) are naturally occurring plant components produced in a large range of plants. They can induce biologic responses in vertebrates by mimicking or modulating the action or production of endogenous hormones. This study examined mixtures of 12 food relevant PEs for effects on...... steroid hormone production, aromatase activity, estrogenic activity, and for interaction with the androgen receptor. The results show that a mixture of all tested PEs increased estradiol production and decreased testosterone production in H295R human adrenal corticocarcinoma cells, indicating an induced...

  4. Aromatase inhibiting and combined estrogenic effects of parabens and estrogenic effects of other additives in cosmetics

    International Nuclear Information System (INIS)

    There is concern widely on the increase in human exposure to exogenous (anti)estrogenic compounds. Typical are certain ingredients in cosmetic consumer products such as musks, phthalates and parabens. Monitoring a variety of human samples revealed that these ingredients, including the ones that generally are considered to undergo rapid metabolism, are present at low levels. In this in vitro research individual compounds and combinations of parabens and endogenous estradiol (E2) were investigated in the MCF-7 cell proliferation assay. The experimental design applied a concentration addition model (CA). Data were analyzed with the estrogen equivalency (EEQ) and method of isoboles approach. In addition, the catalytic inhibitory properties of parabens on an enzyme involved in a rate limiting step in steroid genesis (aromatase) were studied in human placental microsomes. Our results point to an additive estrogenic effect in a CA model for parabens. In addition, it was found that parabens inhibit aromatase. Noticeably, the effective levels in both our in vitro systems were far higher than the levels detected in human samples. However, estrogenic compounds may contribute in a cumulative way to the circulating estrogen burden. Our calculation for the extra estrogen burden due to exposure to parabens, phthalates and polycyclic musks indicates an insignificant estrogenic load relative to the endogenous or therapeutic estrogen burden

  5. Aromatase, adiposity, aging and disease. The hypogonadal-metabolic-atherogenic-disease and aging connection.

    Science.gov (United States)

    Cohen, P G

    2001-06-01

    In males, aging, health and disease are processes that occur over physiologic time and involve a cascade of hormonal, biochemical and physiological changes that accompany the down-regulation of the hypothalamic-anterior pituitary-testicular axis. As aging progresses there are relative increases of body fat and decreases in muscle mass. The increased adipose tissue mass is associated with the production of a number of newly generated factors. These include aromatase, leptin, PAI-1, insulin resistance, and the dyslipidemias, all of which can lead to tissue damage. Fatty tissue becomes the focal point for study as it represents the intersection between energy storage and mobilization. The increase in adipose tissue is associated with an increase in the enzyme aromatase that converts testosterone to estradiol and leads to diminished testosterone levels that favor the preferential deposition of visceral fat. As the total body fat mass increases, hormone resistance develops for leptin and insulin. Increasing leptin fails to prevent weight gain and the hypogonadal-obesity cycle ensues causing further visceral obesity and insulin resistance. The progressive insulin resistance leads to a high triglyceride-low HDL pattern of dyslipidemia and increased cardiovascular risk. All of these factors eventually contribute to the CHAOS Complex: coronary disease, hypertension, adult-onset diabetes mellitus, obesity and/or stroke as permanent changes unfold. Other consequences of the chronic hypogonadal state include osteopenia, extreme fatigue, depression, insomnia, loss of aggressiveness and erectile dysfunction all of which develop over variable periods of time. PMID:11399122

  6. The caspase-3 inhibitor (peptide Z-DEVD-FMK) affects the survival and function of platelets in platelet concentrate during storage

    OpenAIRE

    Shiri, Reza; Yari, Fatemeh; Ahmadinejad, Minoo; Vaeli, Shahram; Tabatabaei, Mohammad Reza

    2014-01-01

    Background Although apoptosis occurs in nucleated cells, studies show that this event also occurs in some anucleated cells such as platelets. During storage of platelets, the viability of platelets decreased, storage lesions were observed, and cells underwent apoptosis. We investigated the effects of caspase-3 inhibitor on the survival and function of platelets after different periods of storage. Methods Platelet concentrates were obtained from the Iranian Blood Transfusion Organization in pl...

  7. OMEGA-3 fatty acids contribute to plaque stability differentially affecting the release of matrix metalloproteinases and tissue inhibitors of metalloproteinases by human monocytes/macrophages in culture

    OpenAIRE

    Massaro, Marika; Scoditti, Egeria; Carluccio, Maria Annunziata; Storelli, Carlo; Distante, Alessandro; Martines, Giuseppe

    2008-01-01

    Objectives. High intakes of omega-3 fatty acids has been associated with protection from plaque rupture. The secretion of metalloproteinases (MMPs) by macrophages is believed to play a key role in matrix degradation underlying plaque instability. Conversely, tissue inhibitors of metalloproteinases (TIMPs) would contribute to plaque stability. We therefore studied the effects of omega-3 fatty acids on the release and activity of MMPs and TIMPs in cultured human monocytoid cells. Methods. Human...

  8. The VMAT-2 inhibitor tetrabenazine affects effort-related decision making in a progressive ratio/chow feeding choice task: reversal with antidepressant drugs.

    Directory of Open Access Journals (Sweden)

    Patrick A Randall

    Full Text Available Behavioral activation is a fundamental feature of motivation, and organisms frequently make effort-related decisions based upon evaluations of reinforcement value and response costs. Furthermore, people with major depression and other disorders often show anergia, psychomotor retardation, fatigue, and alterations in effort-related decision making. Tasks measuring effort-based decision making can be used as animal models of the motivational symptoms of depression, and the present studies characterized the effort-related effects of the vesicular monoamine transport (VMAT-2 inhibitor tetrabenazine. Tetrabenazine induces depressive symptoms in humans, and also preferentially depletes dopamine (DA. Rats were assessed using a concurrent progressive ratio (PROG/chow feeding task, in which they can either lever press on a PROG schedule for preferred high-carbohydrate food, or approach and consume a less-preferred lab chow that is freely available in the chamber. Previous work has shown that the DA antagonist haloperidol reduced PROG work output on this task, but did not reduce chow intake, effects that differed substantially from those of reinforcer devaluation or appetite suppressant drugs. The present work demonstrated that tetrabenazine produced an effort-related shift in responding on the PROG/chow procedure, reducing lever presses, highest ratio achieved and time spent responding, but not reducing chow intake. Similar effects were produced by administration of the subtype selective DA antagonists ecopipam (D1 and eticlopride (D2, but not by the cannabinoid CB1 receptor neutral antagonist and putative appetite suppressant AM 4413, which suppressed both lever pressing and chow intake. The adenosine A2A antagonist MSX-3, the antidepressant and catecholamine uptake inhibitor bupropion, and the MAO-B inhibitor deprenyl, all reversed the impairments induced by tetrabenazine. This work demonstrates the potential utility of the PROG/chow procedure as a

  9. A supra-cellular model for coupling of bone resorption to formation during remodeling: lessons from two bone resorption inhibitors affecting bone formation differently.

    Science.gov (United States)

    Jensen, Pia Rosgaard; Andersen, Thomas Levin; Pennypacker, Brenda L; Duong, Le T; Engelholm, Lars H; Delaissé, Jean-Marie

    2014-01-10

    The bone matrix is maintained functional through the combined action of bone resorbing osteoclasts and bone forming osteoblasts, in so-called bone remodeling units. The coupling of these two activities is critical for securing bone replenishment and involves osteogenic factors released by the osteoclasts. However, the osteoclasts are separated from the mature bone forming osteoblasts in time and space. Therefore the target cell of these osteoclastic factors has remained unknown. Recent explorations of the physical microenvironment of osteoclasts revealed a cell layer lining the bone marrow and forming a canopy over the whole remodeling surface, spanning from the osteoclasts to the bone forming osteoblasts. Several observations show that these canopy cells are a source of osteoblast progenitors, and we hypothesized therefore that they are the likely cells targeted by the osteogenic factors of the osteoclasts. Here we provide evidence supporting this hypothesis, by comparing the osteoclast-canopy interface in response to two types of bone resorption inhibitors in rabbit lumbar vertebrae. The bisphosphonate alendronate, an inhibitor leading to low bone formation levels, reduces the extent of canopy coverage above osteoclasts. This effect is in accordance with its toxic action on periosteoclastic cells. In contrast, odanacatib, an inhibitor preserving bone formation, increases the extent of the osteoclast-canopy interface. Interestingly, these distinct effects correlate with how fast bone formation follows resorption during these respective treatments. Furthermore, canopy cells exhibit uPARAP/Endo180, a receptor able to bind the collagen made available by osteoclasts, and reported to mediate osteoblast recruitment. Overall these observations support a mechanism where the recruitment of bone forming osteoblasts from the canopy is induced by osteoclastic factors, thereby favoring initiation of bone formation. They lead to a model where the osteoclast-canopy interface is

  10. Sodium-Glucose Cotransporter 2 Inhibitor and a Low Carbohydrate Diet Affect Gluconeogenesis and Glycogen Content Differently in the Kidney and the Liver of Non-Diabetic Mice

    OpenAIRE

    Atageldiyeva, Kuralay; Fujita, Yukihiro; Yanagimachi, Tsuyoshi; Mizumoto, Katsutoshi; Takeda, Yasutaka; Honjo, Jun; Takiyama, Yumi; Abiko, Atsuko; Makino, Yuichi; Haneda, Masakazu

    2016-01-01

    A low carbohydrate diet (LCHD) as well as sodium glucose cotransporter 2 inhibitors (SGLT2i) may reduce glucose utilization and improve metabolic disorders. However, it is not clear how different or similar the effects of LCHD and SGLT2i are on metabolic parameters such as insulin sensitivity, fat accumulation, and especially gluconeogenesis in the kidney and the liver. We conducted an 8-week study using non-diabetic mice, which were fed ad-libitum with LCHD or a normal carbohydrate diet (NCH...

  11. The interaction between aromatase, metalloproteinase 2,9 and cd44 in breast cancer A interação entre aromatase, metalloproteinase 2, 9 e cd44 no câncer de mama

    Directory of Open Access Journals (Sweden)

    Fábio Bagnoli

    2010-01-01

    Full Text Available OBJECTIVE: This study intends to verify the expression levels and correlation of aromatase, matrix metalloproteinase 2 (MMP-2, matrix metalloproteinase 9 (MMP-9 and CD44 in ductal carcinoma in situ (DCIS and infiltrating ductal carcinoma (IDC when both are found in the same breast. METHODS: One hundred and ten cases were evaluated by tissue microarray (TMA and immunohistochemically screened with anti-aromatase polyclonal antibodies, anti-MMP-2 monoclonal antibodies, anti-MMP-9 policlonal antibodies and anti-CD44 monoclonal antibodies. RESULTS: Aromatase was expressed in IDC and DCIS in 63 (57.3% and 60 (67% of the cases respectively; MMP-2 was similarly expressed in IDC and DCIS in 15 (13.60% cases; MMP-9 was positively expressed in IDC and DCIS in 83 (75.50% and 82 (74.50% cases, respectively; CD44 was positively expressed in IDC and DCIS in 49 (44.50% and 48 (42.60% of the cases, respectively; all of them were highly correlated (pOBJETIVO: O objetivo desse estudo é verificar as expressões e correlações da aromatase, metalloproteinase 2 da matriz (MMP2, metalloproteinase 9 da matriz (MMP-9 e CD44 no carcinoma ductal in situ (CDIS e carcinoma ductal infiltrativo (CDI quando ambos estão presentes simultaneamente na mesma mama. MÉTODOS: Foram avaliados 110 casos pelo método de tissue microarray (TMA e através da utilização de anticorpos policlonais antiaromatase, anticorpos monoclonais anti-MMP-2, anticorpos policlonais anti-MMP-9 e anticorpos monoclonais anti-CD44. RESULTADOS: A aromatase estava expressa de forma positiva no CDI e CDIS em 63 (57,3% e 60 (67% casos, respectivamente. A expressão de MMP-2 estava expressa de forma positiva em 15 (13,6% casos tanto no CDI, quanto no CDIS. A expressão da MMP-9 estava expressa de forma positiva em 83 (75,5% e 82 (74,5% casos de CDI e CDIS, respectivamente. A expressão de CD44 estava expressa de forma positiva em 49 (44,5% e 48 (42,6% casos de CDI e CDIS, respectivamente. Todos eles

  12. New insights about the evaluation of human sperm quality: the aromatase example.

    Directory of Open Access Journals (Sweden)

    A Saad

    2010-01-01

    Full Text Available Male contribution to the couple's infertility is at first evaluated by the routine examination of semen parameters upon optical microscopy providing valuable information for a rational initial diagnosis and for a clinical management of infertility. But the different forms of infertility defined according to the WHO criteria especially teratozoospermia are not always related to the chromatin structure or to the fertilization capacity. New investigations at the molecular level (transcript and protein could be developed in order to understand the nature of sperm malformation responsible of human infertility and thus to evaluate the sperm quality. The profile analysis of spermatozoal transcripts could be considered as a fingerprint of the past spermatogenic events. The selection of representative transcripts of normal spermatozoa remains complex because a differential expression (increased, decreased or not modified levels of specific transcripts has been revealed between immotile and motile sperm fractions issued from normozoospermic donors. Microarrays tests or real-time quantitative PCR could be helpful for the identification of factors involved in the male infertility. Differences in the expression of specific transcripts have been reported between normal and abnormal semen samples. With the aromatase example, we have noted a negative strong correlation between the amount of transcript and the percentage of abnormal forms especially in presence of head defects. Immunocytochemical procedures using fluorescent probes associated with either confocal microscopy or flow cytometry can be also helpful to proceed with further investigations about the localization of proteins in the compartmentalized spermatozoa or the acrosome reaction. The dual location of aromatase both in the equatorial segment, the mid-piece and the tail could explain the double role of this enzyme in acrosome reaction and motility.

  13. Frequency of Polymorphism in Aromatase Enzyme Coding Gene with Prostate Cancer Risk in North Indian Population

    Directory of Open Access Journals (Sweden)

    KH Onsory

    2015-10-01

    Full Text Available Background: A series of biochemical reactions are involved in the endogenous production of estrogens. Their final and rate-limiting step is catalyzed by aromatase belonging to the class XIX of cytochrome P450. CYP19 is a key enzyme for estrogen synthesis in males. It catalyzes the irreversible conversion of androstenedione and testosterone to estrone and estradiol-17β, respectively. Aromatase P450 is present in the endoplasmic reticulum of estrogen-reproducing cells in which it is expressed. The effects of the resulting estrogens are mediated through the estrogen receptor. One of the most important polymorphism, is a C to T variation in exon 7 resulting in an Arg264Cys amino acid exchange, has been shown to be very common in Asia. The purpose of this study was to determine the association of CYP19 gene polymorphism with the prostate cancer risk among the studied population. Methods: PCR-RFLP analysis of CYP19 gene was on 100 prostate cancer patients and an equal number of matching controls. The data was analyzed using the computer software SPSS for windows (version 19. Results: The frequency of CT genotype was higher in patients (37% as compared to controls (21.2% and this incidence was statistically significant (OR, 2.10; 95 % CI, 1.02-4.34; P=0.044. Stratification of patients according to the risk factors, resulted in a slightly improved OR in individuals carrying CT compared to CC genotype (OR, 2.35 95% CI, 1.11-4.96; P=0.024. The TT genotype was not significantly associated with prostate cancer risk (OR, 0.63; 95% CI, 0.16-2.50; P=0.519. Conclusion: It seems that CT genotype is more associated with cancer prostate compare with other genotypes. It appears to be an increased risk of prostate cancer associated with the Arg264Cys substitution in the CYP19 gene.

  14. Characterization of Aromatase Expression in the Adult Male and Female Mouse Brain. I. Coexistence with Oestrogen Receptors α and β, and Androgen Receptors

    OpenAIRE

    Davor Stanić; Sydney Dubois; Hui Kheng Chua; Bruce Tonge; Nicole Rinehart; Malcolm K Horne; Wah Chin Boon

    2014-01-01

    Aromatase catalyses the last step of oestrogen synthesis. There is growing evidence that local oestrogens influence many brain regions to modulate brain development and behaviour. We examined, by immunohistochemistry, the expression of aromatase in the adult male and female mouse brain, using mice in which enhanced green fluorescent protein (EGFP) is transcribed following the physiological activation of the Cyp19A1 gene. EGFP-immunoreactive processes were distributed in many brain regions, in...

  15. Nuclear localization of CPI-17, a protein phosphatase-1 inhibitor protein, affects histone H3 phosphorylation and corresponds to proliferation of cancer and smooth muscle cells

    International Nuclear Information System (INIS)

    Highlights: •Non-canonical roles of the myosin phosphatase inhibitor (CPI-17) were studied. •CPI-17 is localized in the nucleus of hyperplastic cancer and smooth muscle cells. •CPI-17 Ser12 phosphorylation may regulate the nuclear import. •CPI-17 regulates histone H3 phosphorylation and cell proliferation. •The nuclear CPI-17-PP1 axis plays a proliferative role in cells. -- Abstract: CPI-17 (C-kinase-activated protein phosphatase-1 (PP1) inhibitor, 17 kDa) is a cytoplasmic protein predominantly expressed in mature smooth muscle (SM) that regulates the myosin-associated PP1 holoenzyme (MLCP). Here, we show CPI-17 expression in proliferating cells, such as pancreatic cancer and hyperplastic SM cells. Immunofluorescence showed that CPI-17 was concentrated in nuclei of human pancreatic cancer (Panc1) cells. Nuclear accumulation of CPI-17 was also detected in the proliferating vascular SM cell culture and cells at neointima of rat vascular injury model. The N-terminal 21-residue tail domain of CPI-17 was necessary for the nuclear localization. Phospho-mimetic Asp-substitution of CPI-17 at Ser12 attenuated the nuclear import. CPI-17 phosphorylated at Ser12 was not localized at nuclei, suggesting a suppressive role of Ser12 phosphorylation in the nuclear import. Activated CPI-17 bound to all three isoforms of PP1 catalytic subunit in Panc1 nuclear extracts. CPI-17 knockdown in Panc1 resulted in dephosphorylation of histone H3 at Thr3, Ser10 and Thr11, whereas it had no effects on the phosphorylation of myosin light chain and merlin, the known targets of MLCP. In parallel, CPI-17 knockdown suppressed Panc1 proliferation. We propose that CPI-17 accumulated in the nucleus through the N-terminal tail targets multiple PP1 signaling pathways regulating cell proliferation

  16. Nuclear localization of CPI-17, a protein phosphatase-1 inhibitor protein, affects histone H3 phosphorylation and corresponds to proliferation of cancer and smooth muscle cells

    Energy Technology Data Exchange (ETDEWEB)

    Eto, Masumi, E-mail: masumi.eto@jefferson.edu [Department of Molecular Physiology and Biophysics, and Kimmel Cancer Center, Thomas Jefferson University, 1020 Locust Street, PA 19107 (United States); Kirkbride, Jason A.; Chugh, Rishika; Karikari, Nana Kofi [Department of Molecular Physiology and Biophysics, and Kimmel Cancer Center, Thomas Jefferson University, 1020 Locust Street, PA 19107 (United States); Kim, Jee In [Department of Molecular Physiology and Biophysics, and Kimmel Cancer Center, Thomas Jefferson University, 1020 Locust Street, PA 19107 (United States); Cardiovascular Research Institute, Kyungpook National University School of Medicine, Daegu 700-422 (Korea, Republic of)

    2013-04-26

    Highlights: •Non-canonical roles of the myosin phosphatase inhibitor (CPI-17) were studied. •CPI-17 is localized in the nucleus of hyperplastic cancer and smooth muscle cells. •CPI-17 Ser12 phosphorylation may regulate the nuclear import. •CPI-17 regulates histone H3 phosphorylation and cell proliferation. •The nuclear CPI-17-PP1 axis plays a proliferative role in cells. -- Abstract: CPI-17 (C-kinase-activated protein phosphatase-1 (PP1) inhibitor, 17 kDa) is a cytoplasmic protein predominantly expressed in mature smooth muscle (SM) that regulates the myosin-associated PP1 holoenzyme (MLCP). Here, we show CPI-17 expression in proliferating cells, such as pancreatic cancer and hyperplastic SM cells. Immunofluorescence showed that CPI-17 was concentrated in nuclei of human pancreatic cancer (Panc1) cells. Nuclear accumulation of CPI-17 was also detected in the proliferating vascular SM cell culture and cells at neointima of rat vascular injury model. The N-terminal 21-residue tail domain of CPI-17 was necessary for the nuclear localization. Phospho-mimetic Asp-substitution of CPI-17 at Ser12 attenuated the nuclear import. CPI-17 phosphorylated at Ser12 was not localized at nuclei, suggesting a suppressive role of Ser12 phosphorylation in the nuclear import. Activated CPI-17 bound to all three isoforms of PP1 catalytic subunit in Panc1 nuclear extracts. CPI-17 knockdown in Panc1 resulted in dephosphorylation of histone H3 at Thr3, Ser10 and Thr11, whereas it had no effects on the phosphorylation of myosin light chain and merlin, the known targets of MLCP. In parallel, CPI-17 knockdown suppressed Panc1 proliferation. We propose that CPI-17 accumulated in the nucleus through the N-terminal tail targets multiple PP1 signaling pathways regulating cell proliferation.

  17. Protein kinase C delta (PKCδ affects proliferation of insulin-secreting cells by promoting nuclear extrusion of the cell cycle inhibitor p21Cip1/WAF1.

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    Felicia Ranta

    Full Text Available BACKGROUND: High fat diet-induced hyperglycemia and palmitate-stimulated apoptosis was prevented by specific inhibition of protein kinase C delta (PKCδ in β-cells. To understand the role of PKCδ in more detail the impact of changes in PKCδ activity on proliferation and survival of insulin-secreting cells was analyzed under stress-free conditions. METHODOLOGY AND PRINCIPAL FINDINGS: Using genetic and pharmacological approaches, the effect of reduced and increased PKCδ activity on proliferation, apoptosis and cell cycle regulation of insulin secreting cells was examined. Proteins were analyzed by Western blotting and by confocal laser scanning microscopy. Increased expression of wild type PKCδ (PKCδWT significantly stimulated proliferation of INS-1E cells with concomitant reduced expression and cytosolic retraction of the cell cycle inhibitor p21(Cip1/WAF1. This nuclear extrusion was mediated by PKCδ-dependent phosphorylation of p21(Cip1/WAF1 at Ser146. In kinase dead PKCδ (PKCδKN overexpressing cells and after inhibition of endogenous PKCδ activity by rottlerin or RNA interference phosphorylation of p21(Cip1/WAF1 was reduced, which favored its nuclear accumulation and apoptotic cell death of INS-1E cells. Human and mouse islet cells express p21(Cip1/WAF1 with strong nuclear accumulation, while in islet cells of PKCδWT transgenic mice the inhibitor resides cytosolic. CONCLUSIONS AND SIGNIFICANCE: These observations disclose PKCδ as negative regulator of p21(Cip1/WAF1, which facilitates proliferation of insulin secreting cells under stress-free conditions and suggest that additional stress-induced changes push PKCδ into its known pro-apoptotic role.

  18. Sodium-Glucose Cotransporter 2 Inhibitor and a Low Carbohydrate Diet Affect Gluconeogenesis and Glycogen Content Differently in the Kidney and the Liver of Non-Diabetic Mice.

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    Kuralay Atageldiyeva

    Full Text Available A low carbohydrate diet (LCHD as well as sodium glucose cotransporter 2 inhibitors (SGLT2i may reduce glucose utilization and improve metabolic disorders. However, it is not clear how different or similar the effects of LCHD and SGLT2i are on metabolic parameters such as insulin sensitivity, fat accumulation, and especially gluconeogenesis in the kidney and the liver. We conducted an 8-week study using non-diabetic mice, which were fed ad-libitum with LCHD or a normal carbohydrate diet (NCHD and treated with/without the SGLT-2 inhibitor, ipragliflozin. We compared metabolic parameters, gene expression for transcripts related to glucose and fat metabolism, and glycogen content in the kidney and the liver among the groups. SGLT2i but not LCHD improved glucose excursion after an oral glucose load compared to NCHD, although all groups presented comparable non-fasted glycemia. Both the LCHD and SGLT2i treatments increased calorie-intake, whereas only the LCHD increased body weight compared to the NCHD, epididimal fat mass and developed insulin resistance. Gene expression of certain gluconeogenic enzymes was simultaneously upregulated in the kidney of SGLT2i treated group, as well as in the liver of the LCHD treated group. The SGLT2i treated groups showed markedly lower glycogen content in the liver, but induced glycogen accumulation in the kidney. We conclude that LCHD induces deleterious metabolic changes in the non-diabetic mice. Our results suggest that SGLT2i induced gluconeogenesis mainly in the kidney, whereas for LCHD it was predominantly in the liver.

  19. Sodium-Glucose Cotransporter 2 Inhibitor and a Low Carbohydrate Diet Affect Gluconeogenesis and Glycogen Content Differently in the Kidney and the Liver of Non-Diabetic Mice.

    Science.gov (United States)

    Atageldiyeva, Kuralay; Fujita, Yukihiro; Yanagimachi, Tsuyoshi; Mizumoto, Katsutoshi; Takeda, Yasutaka; Honjo, Jun; Takiyama, Yumi; Abiko, Atsuko; Makino, Yuichi; Haneda, Masakazu

    2016-01-01

    A low carbohydrate diet (LCHD) as well as sodium glucose cotransporter 2 inhibitors (SGLT2i) may reduce glucose utilization and improve metabolic disorders. However, it is not clear how different or similar the effects of LCHD and SGLT2i are on metabolic parameters such as insulin sensitivity, fat accumulation, and especially gluconeogenesis in the kidney and the liver. We conducted an 8-week study using non-diabetic mice, which were fed ad-libitum with LCHD or a normal carbohydrate diet (NCHD) and treated with/without the SGLT-2 inhibitor, ipragliflozin. We compared metabolic parameters, gene expression for transcripts related to glucose and fat metabolism, and glycogen content in the kidney and the liver among the groups. SGLT2i but not LCHD improved glucose excursion after an oral glucose load compared to NCHD, although all groups presented comparable non-fasted glycemia. Both the LCHD and SGLT2i treatments increased calorie-intake, whereas only the LCHD increased body weight compared to the NCHD, epididimal fat mass and developed insulin resistance. Gene expression of certain gluconeogenic enzymes was simultaneously upregulated in the kidney of SGLT2i treated group, as well as in the liver of the LCHD treated group. The SGLT2i treated groups showed markedly lower glycogen content in the liver, but induced glycogen accumulation in the kidney. We conclude that LCHD induces deleterious metabolic changes in the non-diabetic mice. Our results suggest that SGLT2i induced gluconeogenesis mainly in the kidney, whereas for LCHD it was predominantly in the liver. PMID:27327650

  20. The role of aromatase inhibitors in ameliorating deleterious effects of ovarian stimulation on outcome of infertility treatment

    OpenAIRE

    Diamond Michael P; Casper Robert F; Mitwally Mohamed FM

    2005-01-01

    Abstract Clinical utilization of ovulation stimulation to facilitate the ability of a couple to conceive has not only provided a valuable therapeutic approach, but has also yielded extensive information on the physiology of ovarian follicular recruitment, endometrial receptivity and early embryo competency. One of the consequences of the use of fertility enhancing agents for ovarian stimulation has been the creation of a hyperestrogenic state, which may influence each of these parameters. Use...

  1. Perspectives of digestive pest control with proteinase inhibitors that mainly affect the trypsin-like activity of Anticarsia gemmatalis Hübner (Lepidoptera: Noctuidae

    Directory of Open Access Journals (Sweden)

    M.E. Pereira

    2005-11-01

    Full Text Available The present study describes the main characteristics of the proteolytic activities of the velvetbean caterpillar, Anticarsia gemmatalis Hübner, and their sensitivity to proteinase inhibitors and activators. Midguts of last instar larvae reared on an artificial diet were homogenized in 0.15 M NaCl and centrifuged at 14,000 g for 10 min at 4ºC and the supernatants were used in enzymatic assays at 30ºC, pH 10.0. Basal total proteolytic activity (azocasein hydrolysis was 1.14 ± 0.15 absorbance variation min-1 mg protein-1, at 420 nm; basal trypsin-like activity (N-benzoyl-L-arginine-p-nitroanilide, BApNA, hydrolysis was 0.217 ± 0.02 mmol p-nitroaniline min-1 mg protein-1. The maximum proteolytic activities were observed at pH 10.5 using azocasein and at pH 10.0 using BApNA, this pH being identical to the midgut pH of 10.0. The maximum trypsin-like activity occurred at 50ºC, a temperature that reduces enzyme stability to 80 and 60% of the original, when pre-incubated for 5 and 30 min, respectively. Phenylmethylsulfonyl fluoride inhibited the proteolytic activities with an IC50 of 0.39 mM for azocasein hydrolysis and of 1.35 mM for BApNA hydrolysis. Benzamidine inhibited the hydrolysis with an IC50 of 0.69 and 0.076 mM for azocasein and BApNA, respectively. The absence of cysteine-proteinases is indicated by the fact that 2-mercaptoethanol and L-cysteine did not increase the rate of azocasein hydrolysis. These results demonstrate the presence of serine-proteinases and the predominance of trypsin-like activity in the midgut of Lepidoptera insects, now also detected in A. gemmatalis, and suggest this enzyme as a major target for pest control based on disruption of protein metabolism using proteinase inhibitors.

  2. Farnesoid X Receptor, through the Binding with Steroidogenic Factor 1-responsive Element, Inhibits Aromatase Expression in Tumor Leydig Cells*

    OpenAIRE

    Catalano, Stefania; Malivindi, Rocco; Giordano, Cinzia; Gu, Guowei; Panza, Salvatore; Bonofiglio, Daniela; Lanzino, Marilena; Sisci, Diego; Panno, Maria Luisa; Andò, Sebastiano

    2009-01-01

    The farnesoid X receptor (FXR) is a member of the nuclear receptor superfamily that regulates bile acid homeostasis. It is expressed in the liver and the gastrointestinal tract, but also in several non-enterohepatic tissues including testis. Recently, FXR was identified as a negative modulator of the androgen-estrogen-converting aromatase enzyme in human breast cancer cells. In the present study we detected the expression of FXR in Leydig normal and tumor cell lines and in rat testes tissue. ...

  3. Dietary Polyphenols Suppress Elevated Levels of Proinflammatory Mediators and Aromatase in the Mammary Gland of Obese Mice

    OpenAIRE

    Subbaramaiah, Kotha; Sue, Erika; Bhardwaj, Priya; Du, Baoheng; Hudis, Clifford A.; Giri, Dilip; Kopelovich, Levy; Zhou, Xi Kathy; Dannenberg, Andrew J.

    2013-01-01

    In postmenopausal women, obesity is a risk factor for the development of hormone receptor-positive breast cancer driven by estrogen. After menopause, aromatization of androgen precursors in adipose tissue is a major synthetic source of estrogen. Recently, in mouse models and women, we identified an obesity-inflammation-aromatase axis. This obesity induced inflammation is characterized by crown-like structures (CLS) consisting of dead adipocytes encircled by macrophages in breast white adipose...

  4. Brain aromatase and circulating corticosterone are rapidly regulated by combined acute stress and sexual interaction in a sex specific manner

    OpenAIRE

    Dickens, M.J.; Balthazart, J.; Cornil, C. A.

    2012-01-01

    Neural production of 17β-oestradiol via aromatisation of testosterone may play a critical role in rapid, non-genomic regulation of physiological and behavioural processes. In brain nuclei implicated in the control of sexual behaviour, sexual or stressfull stimuli induce respectively a rapid inhibition or increase in preoptic aromatase activity (AA). Here, we tested quail that were either non-stressed or acutely stressed (15 min restraint) immediately prior to sexual interaction (5 min) with s...

  5. The effect of oral contraceptives on aromatase and Cox-2 expression in the endometrium of patients with idiopathic menorrhagia or adenomyosis

    Directory of Open Access Journals (Sweden)

    Maia H Jr

    2013-06-01

    Full Text Available Hugo Maia Jr,1–3 Clarice Haddad,3 Nathaniel Pinheiro,4 Julio Casoy31School of Medicine, Federal University of Bahia, Salvador, Bahia, Brazil; 2Itaigara Memorial Day Hospital, Salvador, Bahia, Brazil; 3CEPARH (Centro de Pesquisas e Assistência em Reprodução Humana, Salvador, Bahia, Brazil; 4Imagepat Pathology Laboratory, Federal University of Bahia, Salvador, Bahia, BrazilBackground: The presence of aromatase and cyclooxygenase-2 (Cox-2 expression was investigated in the endometrium of patients with idiopathic menorrhagia or adenomyosis. The effect of oral contraceptives administered in extended regimens on the endometrial expression of these enzymes was also investigated.Methods and results: Aromatase expression was detected by immunohistochemistry in the endometrial glands and stroma of patients with idiopathic menorrhagia or adenomyosis. There was no difference in the percentage of aromatase expression in the endometria between the two groups. The mean intensity of Cox-2 expression in the glandular epithelium also did not differ significantly between the groups. Among the patients using oral contraceptives in extended regimens, the relative decrease in both aromatase and Cox-2 expression was significantly greater in amenorrheic patients compared with those who were experiencing breakthrough bleeding.Conclusion: The presence of aromatase expression in the endometrium is associated with the occurrence of menorrhagia, irrespective of the presence of adenomyosis. Continuous expression of these enzymes in the endometrium of users of oral contraceptives in extended regimens is positively associated with the presence of breakthrough bleeding. This suggests a role for both aromatase and Cox-2 in the etiology of abnormal uterine bleeding.Keywords: menorrhagia, aromatase, endometrium, Cox-2, adenomyosis

  6. Diverse inhibitor chemotypes targeting Trypanosoma cruzi CYP51.

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    Shamila S Gunatilleke

    Full Text Available BACKGROUND: Chagas Disease, a WHO- and NIH-designated neglected tropical disease, is endemic in Latin America and an emerging infection in North America and Europe as a result of population moves. Although a major cause of morbidity and mortality due to heart failure, as well as inflicting a heavy economic burden in affected regions, Chagas Disease elicits scant notice from the pharmaceutical industry because of adverse economic incentives. The discovery and development of new routes to chemotherapy for Chagas Disease is a clear priority. METHODOLOGY/PRINCIPAL FINDINGS: The similarity between the membrane sterol requirements of pathogenic fungi and those of the parasitic protozoon Trypanosoma cruzi, the causative agent of Chagas human cardiopathy, has led to repurposing anti-fungal azole inhibitors of sterol 14α-demethylase (CYP51 for the treatment of Chagas Disease. To diversify the therapeutic pipeline of anti-Chagasic drug candidates we exploited an approach that included directly probing the T. cruzi CYP51 active site with a library of synthetic small molecules. Target-based high-throughput screening reduced the library of ∼104,000 small molecules to 185 hits with estimated nanomolar K(D values, while cross-validation against T. cruzi-infected skeletal myoblast cells yielded 57 active hits with EC(50 <10 µM. Two pools of hits partially overlapped. The top hit inhibited T. cruzi with EC(50 of 17 nM and was trypanocidal at 40 nM. CONCLUSIONS/SIGNIFICANCE: The hits are structurally diverse, demonstrating that CYP51 is a rather permissive enzyme target for small molecules. Cheminformatic analysis of the hits suggests that CYP51 pharmacology is similar to that of other cytochromes P450 therapeutic targets, including thromboxane synthase (CYP5, fatty acid ω-hydroxylases (CYP4, 17α-hydroxylase/17,20-lyase (CYP17 and aromatase (CYP19. Surprisingly, strong similarity is suggested to glutaminyl-peptide cyclotransferase, which is unrelated to CYP

  7. The 37/67kDa laminin receptor (LR) inhibitor, NSC47924, affects 37/67kDa LR cell surface localization and interaction with the cellular prion protein

    Science.gov (United States)

    Sarnataro, Daniela; Pepe, Anna; Altamura, Gennaro; De Simone, Imma; Pesapane, Ada; Nitsch, Lucio; Montuori, Nunzia; Lavecchia, Antonio; Zurzolo, Chiara

    2016-01-01

    The 37/67 kDa laminin receptor (LR) is a non-integrin protein, which binds both laminin-1 of the extracellular matrix and prion proteins, that hold a central role in prion diseases. The 37/67 kDa LR has been identified as interactor for the prion protein (PrPC) and to be required for pathological PrP (PrPSc) propagation in scrapie-infected neuronal cells, leading to the possibility that 37/67 kDa LR-PrPC interaction is related to the pathogenesis of prion diseases. A relationship between 37/67 kDa LR and PrPC in the presence of specific LR inhibitor compounds has not been investigated yet. We have characterized the trafficking of 37/67 kDa LR in both neuronal and non-neuronal cells, finding the receptor on the cell surface and nuclei, and identified the 67 kDa LR as the almost exclusive isoform interacting with PrPC. Here, we show that the treatment with the 37/67 kDa LR inhibitor, NSC47924, affects both the direct 37/67 kDa LR-PrPC interaction in vitro and the formation of the immunocomplex in live cells, inducing a progressive internalization of 37/67 kDa LR and stabilization of PrPC on the cell surface. These data reveal NSC47924 as a useful tool to regulate PrPC and 37/67 kDa LR trafficking and degradation, representing a novel small molecule to be tested against prion diseases. PMID:27071549

  8. Rapid increase in aggressive behavior precedes the decrease in brain aromatase activity during socially mediated sex change in Lythrypnus dalli

    OpenAIRE

    Black, Michael P; Balthazart, Jacques; Baillien, Michelle; Grober, Matthew S.

    2010-01-01

    In the bluebanded goby, Lythrypnus dalli, removal of the male from a social group results in a rapid behavioral response where one female becomes dominant and changes sex to male. In a previous study, within hours of male removal, aromatase activity in the brain (bAA) of dominant females was almost 50% lower than that of control females from a group in which the male had not been removed. For those females that displayed increased aggressive behavior after the male was removed, the larger the...

  9. Effects of Estrogens on Adipokines and Glucose Homeostasis in Female Aromatase Knockout Mice.

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    Michelle L Van Sinderen

    Full Text Available The maintenance of glucose homeostasis within the body is crucial for constant and precise performance of energy balance and is sustained by a number of peripheral organs. Estrogens are known to play a role in the maintenance of glucose homeostasis. Aromatase knockout (ArKO mice are estrogen-deficient and display symptoms of dysregulated glucose metabolism. We aim to investigate the effects of estrogen ablation and exogenous estrogen administration on glucose homeostasis regulation. Six month-old female wildtype, ArKO, and 17β-estradiol (E2 treated ArKO mice were subjected to whole body tolerance tests, serum examination of estrogen, glucose and insulin, ex-vivo muscle glucose uptake, and insulin signaling pathway analyses. Female ArKO mice display increased body weight, gonadal (omental adiposity, hyperinsulinemia, and liver triglycerides, which were ameliorated upon estrogen treatment. Tolerance tests revealed that estrogen-deficient ArKO mice were pyruvate intolerant hence reflecting dysregulated hepatic gluconeogenesis. Analyses of skeletal muscle, liver, and adipose tissues supported a hepatic-based glucose dysregulation, with a down-regulation of Akt phosphorylation (a key insulin signaling pathway molecule in the ArKO liver, which was improved with E2 treatment. Concurrently, estrogen treatment lowered ArKO serum leptin and adiponectin levels and increased inflammatory adipokines such as tumour necrosis factor alpha (TNFα and interleukin 6 (IL6. Furthermore, estrogen deficiency resulted in the infiltration of CD45 macrophages into gonadal adipose tissues, which cannot be reversed by E2 treatment. This study describes the effects of estrogens on glucose homeostasis in female ArKO mice and highlights a primary phenotype of hepatic glucose dysregulation and a parallel estrogen modified adipokine profile.

  10. Corrosion inhibitors

    International Nuclear Information System (INIS)

    In this paper, we briefly describe the characteristics, cost and electrochemical nature of the corrosion phenomena as well as some of the technologies that are currently employed to minimize its effect. The main subject of the paper however, deals with the description, classification and mechanism of protection of the so-called corrosion inhibitors. Examples of the use of these substances in different aggressive environments are also presented as means to show that these compounds, or their combination, can in fact be used as excellent and relatively cheap technologies to control the corrosion of some metals. In the last part of the paper, the most commonly used techniques to evaluate the efficiency and performance of corrosion inhibitors are presented as well as some criteria to make a careful and proper selection of a corrosion inhibitor technology in a given situation. (Author) 151 refs

  11. Estradiol differentially affects auditory recognition and learning according to photoperiodic state in the adult male songbird, European starling (Sturnus vulgaris

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    Rebecca M. Calisi

    2013-09-01

    Full Text Available Changes in hormones can affect many types of learning in vertebrates. Adults experience fluctuations in a multitude of hormones over a temporal scale, from local, rapid action to more long-term, seasonal changes. Endocrine changes during development can affect behavioral outcomes in adulthood, but how learning is affected in adults by hormone fluctuations experienced during adulthood is less understood. Previous reports have implicated the sex steroid hormone estradiol (E2 in both male and female vertebrate cognitive functioning. Here, we examined the effects of E2 on auditory recognition and learning in male European starlings (Sturnus vulgaris. European starlings are photoperiodic, seasonally breeding songbirds that undergo different periods of reproductive activity according to annual changes in day length. We simulated these reproductive periods, specifically 1. photosensitivity, 2. photostimulation, and 3. photorefractoriness in captive birds by altering day length. During each period, we manipulated circulating E2 and examined multiple measures of learning. To manipulate circulating E2, we used subcutaneous implants containing either 17-β E2 and/or fadrozole (FAD, a highly specific aromatase inhibitor that suppresses E2 production in the body and the brain, and measured the latency for birds to learn and respond to short, male conspecific song segments (motifs. We report that photostimulated birds given E2 had higher response rates and responded with better accuracy than those given saline controls or FAD. Conversely, photosensitive, animals treated with E2 responded with less accuracy than those given FAD. These results demonstrate how circulating E2 and photoperiod can interact to shape auditory recognition and learning in adults, driving it in opposite directions in different states.

  12. Co-Formulants in Glyphosate-Based Herbicides Disrupt Aromatase Activity in Human Cells below Toxic Levels

    Directory of Open Access Journals (Sweden)

    Nicolas Defarge

    2016-02-01

    Full Text Available Pesticide formulations contain declared active ingredients and co-formulants presented as inert and confidential compounds. We tested the endocrine disruption of co-formulants in six glyphosate-based herbicides (GBH, the most used pesticides worldwide. All co-formulants and formulations were comparably cytotoxic well below the agricultural dilution of 1% (18–2000 times for co-formulants, 8–141 times for formulations, and not the declared active ingredient glyphosate (G alone. The endocrine-disrupting effects of all these compounds were measured on aromatase activity, a key enzyme in the balance of sex hormones, below the toxicity threshold. Aromatase activity was decreased both by the co-formulants alone (polyethoxylated tallow amine—POEA and alkyl polyglucoside—APG and by the formulations, from concentrations 800 times lower than the agricultural dilutions; while G exerted an effect only at 1/3 of the agricultural dilution. It was demonstrated for the first time that endocrine disruption by GBH could not only be due to the declared active ingredient but also to co-formulants. These results could explain numerous in vivo results with GBHs not seen with G alone; moreover, they challenge the relevance of the acceptable daily intake (ADI value for GBHs exposures, currently calculated from toxicity tests of the declared active ingredient alone.

  13. Co-Formulants in Glyphosate-Based Herbicides Disrupt Aromatase Activity in Human Cells below Toxic Levels

    Science.gov (United States)

    Defarge, Nicolas; Takács, Eszter; Lozano, Verónica Laura; Mesnage, Robin; Spiroux de Vendômois, Joël; Séralini, Gilles-Eric; Székács, András

    2016-01-01

    Pesticide formulations contain declared active ingredients and co-formulants presented as inert and confidential compounds. We tested the endocrine disruption of co-formulants in six glyphosate-based herbicides (GBH), the most used pesticides worldwide. All co-formulants and formulations were comparably cytotoxic well below the agricultural dilution of 1% (18–2000 times for co-formulants, 8–141 times for formulations), and not the declared active ingredient glyphosate (G) alone. The endocrine-disrupting effects of all these compounds were measured on aromatase activity, a key enzyme in the balance of sex hormones, below the toxicity threshold. Aromatase activity was decreased both by the co-formulants alone (polyethoxylated tallow amine—POEA and alkyl polyglucoside—APG) and by the formulations, from concentrations 800 times lower than the agricultural dilutions; while G exerted an effect only at 1/3 of the agricultural dilution. It was demonstrated for the first time that endocrine disruption by GBH could not only be due to the declared active ingredient but also to co-formulants. These results could explain numerous in vivo results with GBHs not seen with G alone; moreover, they challenge the relevance of the acceptable daily intake (ADI) value for GBHs exposures, currently calculated from toxicity tests of the declared active ingredient alone. PMID:26927151

  14. Co-Formulants in Glyphosate-Based Herbicides Disrupt Aromatase Activity in Human Cells below Toxic Levels.

    Science.gov (United States)

    Defarge, Nicolas; Takács, Eszter; Lozano, Verónica Laura; Mesnage, Robin; Spiroux de Vendômois, Joël; Séralini, Gilles-Eric; Székács, András

    2016-01-01

    Pesticide formulations contain declared active ingredients and co-formulants presented as inert and confidential compounds. We tested the endocrine disruption of co-formulants in six glyphosate-based herbicides (GBH), the most used pesticides worldwide. All co-formulants and formulations were comparably cytotoxic well below the agricultural dilution of 1% (18-2000 times for co-formulants, 8-141 times for formulations), and not the declared active ingredient glyphosate (G) alone. The endocrine-disrupting effects of all these compounds were measured on aromatase activity, a key enzyme in the balance of sex hormones, below the toxicity threshold. Aromatase activity was decreased both by the co-formulants alone (polyethoxylated tallow amine-POEA and alkyl polyglucoside-APG) and by the formulations, from concentrations 800 times lower than the agricultural dilutions; while G exerted an effect only at 1/3 of the agricultural dilution. It was demonstrated for the first time that endocrine disruption by GBH could not only be due to the declared active ingredient but also to co-formulants. These results could explain numerous in vivo results with GBHs not seen with G alone; moreover, they challenge the relevance of the acceptable daily intake (ADI) value for GBHs exposures, currently calculated from toxicity tests of the declared active ingredient alone. PMID:26927151

  15. Weight gain and inflammation regulate aromatase expression in male adipose tissue, as evidenced by reporter gene activity.

    Science.gov (United States)

    Polari, L; Yatkin, E; Martínez Chacón, M G; Ahotupa, M; Smeds, A; Strauss, L; Zhang, F; Poutanen, M; Saarinen, N; Mäkelä, S I

    2015-09-01

    Obesity and white adipose tissue (WAT) inflammation are associated with enhanced aromatization in women, but little is known about the regulation of aromatase (CYP19A1) gene expression in male WAT. We investigated the impact of weight gain and WAT inflammation on the regulation of CYP19A1 in males, by utilizing the hARO-Luc aromatase reporter mouse model containing a >100-kb 5'-region of the human CYP19A1 gene. We show that hARO-Luc reporter activity is enhanced in WAT of mice with increased adiposity and inflammation. Dexamethasone and TNFα, as well as forskolin and phorbol 12-myristate 13-acetate, upregulate hARO-Luc activity, suggesting the involvement of promoters I.4 and I.3/II. Furthermore, we show that diet enriched with antioxidative plant polyphenols attenuates WAT inflammation and hARO-Luc activity in obese males. In conclusion, our data suggest that obesity-associated WAT inflammation leads to increased peripheral CYP19A1 expression in males, and that polyphenol-enriched diet may have the potential to attenuate excessive aromatization in WAT of obese men. PMID:26054748

  16. Brain cytochrome P450 aromatase activity in roach (Rutilus rutilus): seasonal variations and impact of environmental contaminants.

    Science.gov (United States)

    Geraudie, Perrine; Hinfray, Nathalie; Gerbron, Marie; Porcher, Jean-Marc; Brion, François; Minier, Christophe

    2011-10-01

    P450 aromatase catalyses the conversion of C19 androgens to C18 estrogens which is thought to be essential for the regulation of the reproductive function. In this study, brain aromatase activity (AA) was measured monthly over a reproductive cycle in wild roach (Rutilus rutilus) sampled in a reference site in Normandy. AA peaked during the breeding season, reaching 35 fmol mg(-1)min(-1) in both male and female fish, and was low during the rest of the year except for a significant rise in October. AA was correlated with ovary maturation (measured either as gonado-somatic index or by histological analysis of the gonads) and plasma sex-steroid levels (11-ketotestosterone in males and 17-β-estradiol in females). Measurements of AA in polluted sites showed that activity was significantly upregulated in sites with fish showing high levels of plasma vitellogenin and large proportion of intersexuality (20-50%) thus suggesting the occurrence of estrogenic compounds and their involvement in AA modulation. PMID:21820384

  17. Differential responsiveness of luteinized human granulosa cells to gonadotropins and insulin-like growth factor I for induction of aromatase activity

    International Nuclear Information System (INIS)

    The objective of this study was to examine the in vitro responsiveness of cultured luteinized human granulosa cells over time to insulin-like growth factor 1 (IGF-1), human follicle-stimulating hormone (FSH), and human chorionic gonadotropin (hCG) for the induction of aromatase activity. Granulosa cells were retrieved from preovulatory follicles in patients undergoing in vitro fertilization. Cells were cultured for a period of 72 hours or 10 days. The ability of hCG, human FSH, and/or IGF-I to induce aromatase activity was assayed by the stereospecific release of tritium from [1B-3H]androstenedione. Short-term cultures (72 hours) demonstrated a marked rise in aromatase activity in response to human FSH and IGF-I, whereas a smaller response to hCG was observed. In contrast, 10-day cultures demonstrated responsiveness predominantly to hCG rather than human FSH for the induction of aromatase activity with no remarkable effect of IGF-I. Luteinized human granulosa cells undergo a transformation from an initial human FSH and IGF-I responsive state to an hCG responsive state in long-term cultures

  18. Effect of a hormone-releasing intrauterine system (Mirena® on aromatase and Cox-2 expression in patients with adenomyosis submitted or not, to endometrial resection

    Directory of Open Access Journals (Sweden)

    Maia R

    2012-04-01

    Full Text Available Hugo Maia Jr1,2, Clarice Haddad1, Julio Casoy1, Rebeca Maia1, Nathanael Pinheiro3, Elsimar M Coutinho11Centro de Pesquisa e Assistência em Reprodução Humana (CEPARH, 2Itaigara Memorial Day Hospital, 3IMAGEPAT, Salvador, Bahia, BrazilObjective: To investigate the effect of a levonorgestrel-releasing intrauterine system (Mirena® on aromatase and cyclooxygenase-2 (Cox-2 expression in the endometrium of patients with adenomyosis who were submitted to endometrial resection at the time of insertion, compared to a group not submitted to endometrial resection and a group of controls with adenomyosis not submitted to any previous hormonal treatment.Patients and methods: Patients with adenomyosis (n = 89 were included in this study. Twenty-two patients had been using Mirena® for 5 years but had not been submitted to endometrial resection prior to insertion of the device. Twenty-four patients were submitted to endometrial resection at the time of Mirena® insertion. The remaining 43 patients with adenomyosis had undergone no previous hormonal treatment and served as a control group. Cox-2 and aromatase expression were determined in the endometrium by immunohistochemistry.Results: Use of Mirena® for 5 years reduced aromatase expression in the endometrium; however, this reduction was significantly greater in the uteri previously submitted to endometrial resection. The reduction in Cox-2 expression was significant only in the uteri submitted to endometrial resection followed by the insertion of Mirena®.Conclusion: Endometrial resection followed by the insertion of Mirena® was associated with greater rates of amenorrhea in patients with adenomyosis, which in turn were associated with a more effective inhibition of aromatase and Cox-2 expression in the endometrium.Keywords: aromatase, Mirena®, adenomyosis, Cox-2, endometrium, levonorgestrel

  19. Reinvestigation of the synthesis and evaluation of [N-methyl-{sup 11}C]vorozole, a radiotracer targeting cytochrome P450 aromatase

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sung Won [Medical Department, Brookhaven National Laboratory, Upton, NY 11973 (United States)], E-mail: swkim@bnl.gov; Biegon, Anat; Katsamanis, Zachary E. [Medical Department, Brookhaven National Laboratory, Upton, NY 11973 (United States); Ehrlich, Carolin W. [Johannes-Gutenberg Universitaet Mainz, Institut fuer Organische Chemie, Duesbergweg 10-14, Mainz (Germany); Hooker, Jacob M.; Shea, Colleen [Medical Department, Brookhaven National Laboratory, Upton, NY 11973 (United States); Muench, Lisa [National Institute on Alcoholism and Alcohol Abuse, Bethesda, MD (United States); Xu Youwen; King, Payton; Carter, Pauline; Alexoff, David L. [Medical Department, Brookhaven National Laboratory, Upton, NY 11973 (United States); Fowler, Joanna S. [Medical Department, Brookhaven National Laboratory, Upton, NY 11973 (United States); Department of Psychiatry, Mount Sinai School of Medicine, New York, NY (United States); Department of Chemistry, State University of New York at Stony Brook, Stony Brook, NY (United States)

    2009-04-15

    Introduction: We reinvestigated the synthesis of [N-methyl-{sup 11}C]vorozole, a radiotracer for aromatase, and discovered the presence of an N-methyl isomer which was not removed in the original purification method. Herein we report the preparation and positron emission tomography (PET) studies of pure [N-methyl-{sup 11}C]vorozole. Methods: Norvorozole was alkylated with [{sup 11}C]methyl iodide as previously described and also with unlabeled methyl iodide. A high-performance liquid chromatography (HPLC) method was developed to separate the regioisomers. Nuclear magnetic resonance (NMR) spectroscopy ({sup 13}C and 2D-nuclear Overhauser effect spectroscopy NMR) was used to identify and assign structures to the N-methylated products. Pure [N-methyl-{sup 11}C]vorozole and the contaminating isomer were compared by PET imaging in the baboon. Results: Methylation of norvorozole resulted in a mixture of isomers (1:1:1 ratio) based on new HPLC analysis using a pentafluorophenylpropyl bonded silica column, in which vorozole coeluted one of its isomers under the original HPLC conditions. Baseline separation of the three labeled isomers was achieved. The N-3 isomer was the contaminant of vorozole, thus correcting the original assignment of isomers. PET studies of pure [N-methyl-{sup 11}C]vorozole with and without the contaminating N-3 isomer revealed that only [N-methyl-{sup 11}C]vorozole binds to aromatase. [N-methyl-{sup 11}C]Vorozole accumulated in all brain regions with highest accumulation in the aromatase-rich amygdala and preoptic area. Accumulation was blocked with vorozole and letrozole consistent with reports of some level of aromatase in many brain regions. Conclusions: The discovery of a contaminating labeled isomer and the development of a method for isolating pure [N-methyl-{sup 11}C]vorozole combine to provide a new scientific tool for PET studies of the biology of aromatase and for drug research and development.

  20. Reinvestigation of the synthesis and evaluation of [N-methyl-11C]vorozole, a radiotracer targeting cytochrome P450 aromatase

    International Nuclear Information System (INIS)

    Introduction: We reinvestigated the synthesis of [N-methyl-11C]vorozole, a radiotracer for aromatase, and discovered the presence of an N-methyl isomer which was not removed in the original purification method. Herein we report the preparation and positron emission tomography (PET) studies of pure [N-methyl-11C]vorozole. Methods: Norvorozole was alkylated with [11C]methyl iodide as previously described and also with unlabeled methyl iodide. A high-performance liquid chromatography (HPLC) method was developed to separate the regioisomers. Nuclear magnetic resonance (NMR) spectroscopy (13C and 2D-nuclear Overhauser effect spectroscopy NMR) was used to identify and assign structures to the N-methylated products. Pure [N-methyl-11C]vorozole and the contaminating isomer were compared by PET imaging in the baboon. Results: Methylation of norvorozole resulted in a mixture of isomers (1:1:1 ratio) based on new HPLC analysis using a pentafluorophenylpropyl bonded silica column, in which vorozole coeluted one of its isomers under the original HPLC conditions. Baseline separation of the three labeled isomers was achieved. The N-3 isomer was the contaminant of vorozole, thus correcting the original assignment of isomers. PET studies of pure [N-methyl-11C]vorozole with and without the contaminating N-3 isomer revealed that only [N-methyl-11C]vorozole binds to aromatase. [N-methyl-11C]Vorozole accumulated in all brain regions with highest accumulation in the aromatase-rich amygdala and preoptic area. Accumulation was blocked with vorozole and letrozole consistent with reports of some level of aromatase in many brain regions. Conclusions: The discovery of a contaminating labeled isomer and the development of a method for isolating pure [N-methyl-11C]vorozole combine to provide a new scientific tool for PET studies of the biology of aromatase and for drug research and development.

  1. Dissociable effects of acetylcholinesterase inhibitors and phosphodiesterase type 5 inhibitors on object recognition memory: acquisition versus consolidation

    OpenAIRE

    Prickaerts, L.; SIK, A.; Staay, van der, F.J.; Vente, de, W.; Blokland, A.

    2005-01-01

    Rationale Phosphodiesterase enzyme type 5 (PDE5) inhibitors and acetylcholinesterase (AChE) inhibitors have cognition-enhancing properties. However, it is not known whether these drug classes affect the same memory processes. Objective We investigated the memory-enhancing effects of the PDE5 inhibitor sildenafil and AChE inhibitors metrifonate and donepezil in the object recognition task to find out whether acquisition or consolidation processes were affected by these drugs. Methods The objec...

  2. Regulation effects on soil urease kinetics as affected by urease inhibitor hydroquinone%脲酶抑制剂氢醌对土壤脲酶动力学行为的调控效应

    Institute of Scientific and Technical Information of China (English)

    隽英华; 陈振华; 张玉兰; 张丽莉; 陈利军

    2015-01-01

    研究了不同温度条件下脲酶抑制剂氢醌( HQ)对东北3种典型土壤(白浆土、棕壤、褐土)脲酶动力学参数的影响。结果表明,土壤类型、培养时间、培养温度及其相互作用均显著影响土壤脲酶动力学参数。与对照相比,加入HQ使土壤脲酶米氏常数(Km)增加,最大反应速率(Vmax)降低,表明HQ对土壤脲酶的作用机理属于混合型抑制。与白浆土相比,棕壤和褐土脲酶动力学参数受HQ的影响程度较大,表明高肥力土壤生物学活性较稳定。随着培养时间延长,土壤脲酶Km降低, Vmax和Vmax/Km增加。随着温度升高,土壤脲酶Km和Vmax增加, Vamx/Km无规律性变化。相关性分析表明,土壤脲酶动力学参数Km、 Vmax和Vmax/Km与pH值、有机质、全氮、碱解氮和质地组成之间存在显著相关关系。%The effect of urease inhibitor quinhydrone ( HQ) on kinetic parameters of urease in three typical soils ( i. e. albic soil, brown soil, cinnamon soil) in Northeast China under different temperature conditions. The results showed that, soil type, incubation time, incubation temperature and their interactions significantly influenced soil urease kinetics. Compared with control, Km increase and Vmax decrease in the soils with HQ and it showed HQ was mixed inhibition to soil urease. Compared with albic soil, in brown soil and cinnamon soil the influence on kinetic parameters of soil urease as affected by HQ was greater, which indicated that high fertility soils could have stable biological characteristics. With incubation time increasing, Km decreased, but Vmax and Vmax/Km increased. With incubation temperature increasing, Km and Vmax in-creased, Vmax/Km changed irregularly. Statistical analysis indicated that, Km, Vmax and Vmax/Km of soil urease had significantly correlations with pH, organic matter, total nitrogen, alkali-hydrolyzed nitrogen and texture structure.

  3. Immunolocalization of aromatase, estrogen and estrogen receptor α and β in the epithelium of digestive tract and enteric neurons of amphioxus (Branchiostoma belcheri )

    Institute of Scientific and Technical Information of China (English)

    FANG Yongqiang; WENG Youzhu; YE Rongzhong; LIU Lili

    2005-01-01

    Immunohistochemical localization of aromatase, estrogen and estrogen receptor in the digestive tract and enteric neurons of amphioxus is investigated. It was found that immunoreactive proteins of aromatase, estrogen and ER-α and β are expressed in hepatic diverticulum, epithelial cells of anterior and posterior region of midgut, as well as in enteric neurons, while hindgut showed immunonegative. The results suggest that digestive tract of amphioxus may be able to synthesize estrogen and possess endocrine function, like rat gastric epithelium and enteric neurons in mammals. The present study provides authentic morphological evidence for explaining the action mechanism of estrogen in regulating the digestive function of gut and the functional evolution of estrogen, which has important theoretical significance in amphioxus.

  4. Aromatase enzyme (P450arom mRNA expression in mouse gonads and the effect of intra-peritoneal amino acid injection

    Directory of Open Access Journals (Sweden)

    Hüseyin Baki Çiftci

    2011-07-01

    Full Text Available The aim of this study was show the presence of (P450arom mRNA expressions in mouse gonads and to measure the effect of intra-peritoneal serine/threonine or glycine injections on the expression of aromatase enzyme P450arommRNA. Three different (1.4, 2.4 and 4.4kb P450arom mRNA species were indentified in mouse testis and the ovary. Relative to saline injected group (S, all the species of P450arom enzyme mRNA decreased in serine/threonine (A or glycine (G injected female mice, while all of them were increased in male. Aromatase enzyme mRNA expression is differently regulated in male and female mice.

  5. Effect of a hormone-releasing intrauterine system (Mirena®) on aromatase and Cox-2 expression in patients with adenomyosis submitted or not, to endometrial resection

    OpenAIRE

    Maia, Hugo; Haddad, Clarice; Casoy, Julio; Maia, Rebeca; Pinheiro, Nathanael; Coutinho, Elsimar M.

    2012-01-01

    Objective To investigate the effect of a levonorgestrel-releasing intrauterine system (Mirena®) on aromatase and cyclooxygenase-2 (Cox-2) expression in the endometrium of patients with adenomyosis who were submitted to endometrial resection at the time of insertion, compared to a group not submitted to endometrial resection and a group of controls with adenomyosis not submitted to any previous hormonal treatment. Patients and methods Patients with adenomyosis (n = 89) were included in this st...

  6. The putative P-gp inhibitor telmisartan does not affect the transcellular permeability and cellular uptake of the calcium channel antagonist verapamil in the P-glycoprotein expressing cell line MDCK II MDR1

    DEFF Research Database (Denmark)

    Saaby, Lasse; Tfelt-Hansen, Peer; Brodin, Birger

    2015-01-01

    Verapamil is used in high doses for the treatment of cluster headache. Verapamil has been described as a P-glycoprotein (P-gp, ABCB1) substrate. We wished to evaluate in vitro whether co administration of a P-gp inhibitor with verapamil could be a feasible strategy for increasing CNS uptake of...

  7. Use of mTOR inhibitors in the treatment of breast cancer: an evaluation of factors that influence patient outcomes

    Directory of Open Access Journals (Sweden)

    Jerusalem G

    2014-04-01

    Full Text Available Guy Jerusalem, Andree Rorive, Joelle Collignon Medical Oncology, CHU Sart Tilman Liege, Domaine Universitaire du Sart Tilman, Liege, Belgium Abstract: Many systemic treatment options are available for advanced breast cancer, including endocrine therapy, chemotherapy, anti-human epidermal growth factor receptor 2 (HER2 therapy, and other targeted agents. Recently, everolimus, a mammalian target of rapamycin (mTOR inhibitor, combined with exemestane, an aromatase inhibitor, has been approved in Europe and the USA for patients suffering from estrogen receptor-positive, HER2-negative advanced breast cancer previously treated by a nonsteroidal aromatase inhibitor, based on the results of BOLERO-2 (Breast cancer trials of OraL EveROlimus. This study showed a statistically significant and clinically meaningful improvement in median progression-free survival. Results concerning the impact on overall survival are expected in the near future. This clinically oriented review focuses on the use of mTOR inhibitors in breast cancer. Results reported with first-generation mTOR inhibitors (ridaforolimus, temsirolimus, everolimus are discussed. The current and potential role of mTOR inhibitors is reported according to breast cancer subtype (estrogen receptor-positive HER2-negative, triple-negative, and HER2-positive ER-positive/negative disease. Everolimus is currently being evaluated in the adjuvant setting in high-risk estrogen receptor-positive, HER2-negative early breast cancer. Continuing mTOR inhibition or alternatively administering other drugs targeting the phosphatidylinositol-3-kinase/protein kinase B-mTOR pathway after progression on treatments including an mTOR inhibitor is under evaluation. Potential biomarkers to select patients showing a more pronounced benefit are reviewed, but we are not currently using these biomarkers in routine practice. Subgroup analysis of BOLERO 2 has shown that the benefit is consistent in all subgroups and that it is

  8. The effect of chemical anti-inhibitors on fibrinolytic enzymes and inhibitors

    DEFF Research Database (Denmark)

    Sidelmann, Johannes Jakobsen; Jespersen, J; Kluft, C;

    1997-01-01

    proteases. We studied the influence of chemical anti-inhibitors (chloramine T, flufenamate, sodium lauryl sulfate, and methylamine) on fibrinolytic serine proteases and fibrinolytic enzyme inhibitors using the physiological substrate fibrin as plasmin substrate. Low concentrations of chloramine T (0.01 mmol...... plasminogen activators (apparent recovery > 200%). Sodium lauryl sulfate eliminates the major fibrinolytic enzyme inhibitors, but increases the activity of plasmin (apparent recovery > 200%) and plasminogen activator, urokinase type (apparent recovery 130%). Methylamine affects only plasmin inhibition. We...

  9. Molecular changes of acetylcholinesterase and butyrylcholinesterase in Alzheimer patients during the natural couse of the disease and treatment with cholinesterase inhibitors : Insight into neurochemical mechanisms affecting the progression of the disease

    OpenAIRE

    Darreh-Shori, Taher

    2006-01-01

    Deficits in central cholinergic neurotransmission in the brain correlate with cognitive impairment in Alzheimer disease (AD) patients. This fact has resulted in the introduction of cholinesterase inhibitors (ChEls) e.g. tacrine, donepezil, rivastigmine and galantamine, which are so far the most successful therapeutic agents for symptomatic treatment of AD patients. The ChEls principally act by inhibiting acetylcholinesterase (AChE), which is primarily associated with cells i...

  10. The putative P-gp inhibitor telmisartan does not affect the transcellular permeability and cellular uptake of the calcium channel antagonist verapamil in the P-glycoprotein expressing cell line MDCK II MDR1

    DEFF Research Database (Denmark)

    Saaby, Lasse; Tfelt-Hansen, Peer; Brodin, Birger

    2015-01-01

    Verapamil is used in high doses for the treatment of cluster headache. Verapamil has been described as a P-glycoprotein (P-gp, ABCB1) substrate. We wished to evaluate in vitro whether co administration of a P-gp inhibitor with verapamil could be a feasible strategy for increasing CNS uptake of...... verapamil. Fluxes of radiolabelled verapamil across MDCK II MDR1 monolayers were measured in the absence and presence of the putative P-gp inhibitor telmisartan (a clinically approved drug compound). Verapamil displayed a vectorial basolateral-toapical transepithelial efflux across the MDCK II MDR1...... monolayers with a permeability of 5.7 9 105 cm sec1 compared to an apical to basolateral permeability of 1.3 9 105 cm sec-1. The efflux could be inhibited with the P-gp inhibitor zosuquidar. Zosuquidar (0.4 lmol/L) reduced the efflux ratio (PB-A/PA-B) for verapamil 4.6–1.6. The presence of telmisartan...

  11. Kinetic analysis of the three-step steroid aromatase reaction of human cytochrome P450 19A1.

    Science.gov (United States)

    Sohl, Christal D; Guengerich, F Peter

    2010-06-01

    Cytochrome P450 19A1 (P450 19A1), the aromatase, catalyzes the conversion of androgens to estrogens through a sequential three-step reaction, generating 19-hydroxy and 19-aldehyde intermediates en route to the product estrogen. A procedure for the heterologous expression and purification of P450 19A1 in Escherichia coli was developed (k(cat) of 0.06 s(-1) for the conversion of androstenedione to estrone). Binding of the substrate and intermediates show low micromolar dissociation constants and are at least two-step processes. Rates of reduction of the iron were fast in the presence of substrate, either intermediate, or product. P450 19A1 is a distributive rather than a processive enzyme, with the sequential reaction allowing free dissociation of the intermediates as revealed by pulse-chase experiments. Conversion of androstenedione to estrone (under single turnover conditions) generated a progress curve showing changes in the concentrations of the substrate, intermediates, and product. A minimal kinetic model containing the individual rate constants for the steps in P450 19A1 catalysis was developed to globally fit the time course of the overall reaction, the dissociation constants, the two-step ligand binding, the distributive character, the iron-reduction rates, and the steady-state conversion of the 19-hydroxy androstenedione and 19-aldehyde androstenedione intermediates to estrone. PMID:20385561

  12. Synergistic activity of letrozole and sorafenib on breast cancer cells

    OpenAIRE

    Bonelli, Mara A.; Fumarola, Claudia; Alfieri, Roberta R.; Monica, Silvia; Cavazzoni, Andrea; Galetti, Maricla; Gatti, Rita; Belletti, Silvana; Harris, Adrian L.; Fox, Stephen B.; Evans, Dean B.; Dowsett, Mitch; Martin, Lesley-Ann; Bottini, Alberto; Generali, Daniele

    2010-01-01

    Abstract Estrogens induce breast tumor cell proliferation by directly regulating gene expression via the estrogen receptor (ER) transcriptional activity and by affecting growth factor signaling pathways such as mitogen-activated protein kinase (MAPK) and AKT/mammalian target of rapamycin Complex1 (mTORC1) cascades. In this study we demonstrated the preclinical therapeutic efficacy of combining the aromatase inhibitor letrozole with the multi-kinase inhibitor sorafenib in aromatase-...

  13. Combined down-regulation by aromatase inhibitor and GnRH-agonist in IVF patients with endometriomas-A pilot study

    DEFF Research Database (Denmark)

    Lossl, Kristine; Løssl, Kristine; Loft, Anne; Freiesleben, Nina L C; Bangsbøll, Susanne; Andersen, Claus Yding; Pedersen, Anette T; Hartwell, Dorthe; Andersen, Anders Nyboe

    2009-01-01

    . The aim of this study was to test the concept of combined down-regulation prior to IVF in patients with endometriomas. STUDY DESIGN: Prospective pilot study in a university-based tertiary fertility clinic including 20 infertile patients with endometriomas undergoing IVF/ICSI. The patients received...... goserelin 3.6mg sc on treatment Days 1, 28 and 56, and one daily tablet of anastrozole 1mg from Day 1 to Day 69. Controlled ovarian stimulation was initiated from Day 70. Outcome measures were change in endometriomal volume and serum CA125 during down-regulation, standard IVF parameters including pregnancy......), P=0.007 and P=0.001). In the IVF/ICSI cycle, the number of oocytes retrieved was 7.5 (6.0-10.0) and the fertilization rate was 0.78 (0.38-1.0). Nine patients (45%) conceived, five (25%) had a clinical pregnancy, and three (15%) delivered healthy children (two singletons and one twin). CONCLUSIONS...

  14. Effect of prenatal androgen receptor antagonist or aromatase inhibitor on the differentiation of neuronal Fos responses to estrous female pheromones in the rat accessory olfactory system

    OpenAIRE

    Dominguez, Emilio; Portillo, Wendy; Baum, Michael J.; Bakker, Julie; Paredes, Raul

    2002-01-01

    Many socially relevant odors are detected in rodent species by the vomeronasal organ and subsequently processed by the accessory olfactory system (AOS). We previously found that gonadectomized male and female rats treated in adulthood with testosterone propionate (TP) showed equivalent Fos responses in the AOS to odors derived from estrous females. Likewise, in contrast with numerous other mammalian species, gonadectomized female rats show surprisingly high levels of male-typical mounting beh...

  15. Proton pump inhibitors

    Science.gov (United States)

    Proton pump inhibitors (PPIs) are medicines that work by reducing the amount of stomach acid made by glands in ... Proton pump inhibitors are used to: Relieve symptoms of acid reflux, or gastroesophageal reflux disease (GERD). This is a ...

  16. Proton pump inhibitors

    Science.gov (United States)

    Proton pump inhibitors (PPIs) are medicines that work by reducing the amount of stomach acid made by ... Proton pump inhibitors are used to: Relieve symptoms of acid reflux, or gastroesophageal reflux disease (GERD). This ...

  17. Cyclin A1 and P450 Aromatase Promote Metastatic Homing and Growth of Stem-like Prostate Cancer Cells in the Bone Marrow.

    Science.gov (United States)

    Miftakhova, Regina; Hedblom, Andreas; Semenas, Julius; Robinson, Brian; Simoulis, Athanasios; Malm, Johan; Rizvanov, Albert; Heery, David M; Mongan, Nigel P; Maitland, Norman J; Allegrucci, Cinzia; Persson, Jenny L

    2016-04-15

    Bone metastasis is a leading cause of morbidity and mortality in prostate cancer. While cancer stem-like cells have been implicated as a cell of origin for prostate cancer metastasis, the pathways that enable metastatic development at distal sites remain largely unknown. In this study, we illuminate pathways relevant to bone metastasis in this disease. We observed that cyclin A1 (CCNA1) protein expression was relatively higher in prostate cancer metastatic lesions in lymph node, lung, and bone/bone marrow. In both primary and metastatic tissues, cyclin A1 expression was also correlated with aromatase (CYP19A1), a key enzyme that directly regulates the local balance of androgens to estrogens. Cyclin A1 overexpression in the stem-like ALDH(high) subpopulation of PC3M cells, one model of prostate cancer, enabled bone marrow integration and metastatic growth. Further, cells obtained from bone marrow metastatic lesions displayed self-renewal capability in colony-forming assays. In the bone marrow, cyclin A1 and aromatase enhanced local bone marrow-releasing factors, including androgen receptor, estrogen and matrix metalloproteinase MMP9 and promoted the metastatic growth of prostate cancer cells. Moreover, ALDH(high) tumor cells expressing elevated levels of aromatase stimulated tumor/host estrogen production and acquired a growth advantage in the presence of host bone marrow cells. Overall, these findings suggest that local production of steroids and MMPs in the bone marrow may provide a suitable microenvironment for ALDH(high) prostate cancer cells to establish metastatic growths, offering new approaches to therapeutically target bone metastases. Cancer Res; 76(8); 2453-64. ©2016 AACR. PMID:26921336

  18. Aromatase enzyme (P450arom) mRNA expression in mouse gonads and the effect of intra-peritoneal amino acid injection

    OpenAIRE

    Hüseyin Baki Çiftci

    2011-01-01

    The aim of this study was show the presence of (P450arom) mRNA expressions in mouse gonads and to measure the effect of intra-peritoneal serine/threonine or glycine injections on the expression of aromatase enzyme P450arommRNA. Three different (1.4, 2.4 and 4.4kb) P450arom mRNA species were indentified in mouse testis and the ovary. Relative to saline injected group (S), all the species of P450arom enzyme mRNA decreased in serine/threonine (A) or glycine (G) injected female mice, while all o...

  19. Comparison of the effect of cortisol on aromatase activity and androgen metabolism in two human fibroblast cell lines derived from the same individual

    DEFF Research Database (Denmark)

    Svenstrup, B; Brünner, N; Dombernowsky, P;

    1990-01-01

    The effect of preincubation with cortisol on estrogen and androgen metabolism was investigated in human fibroblast monolayers grown from biopsies of genital and non-genital skin of the same person. The activity in the cells of aromatase, 5 alpha-reductase, 17 beta-hydroxysteroid oxidoreductase and...... 3 alpha-hydroxysteroid oxidoreductase was investigated by isolating estrone, estradiol, estriol, dihydrotestosterone, androstanedione, androsterone, 3 alpha-androstanediol, testosterone and androstenedione after incubation of the cells with [14C]testosterone or [14C]androstenedione. For experiments...

  20. Characterization and expression profile of the ovarian cytochrome P-450 aromatase (cyp19A1) gene during thermolabile sex determination in Pejerrey, Odontesthes bonariensis

    Science.gov (United States)

    Karube, M.; Fernandino, J.I.; Strobl-Mazzulla, P.; Strussmann, C.A.; Yoshizaki, G.; Somoza, G.M.; Patino, R.

    2007-01-01

    Cytochrome P450 aromatase (cyp19) is an enzyme that catalyzes the conversion of androgens to estrogens and may play a role in temperature- dependent sex determination (TSD) of reptiles, amphibians, and fishes. In this study, the ovarian P450 aromatase form (cyp19A1) of pejerrey Odontesthes bonariensis, a teleost with marked TSD, was cloned and its expression profile evaluated during gonadal differentiation at feminizing (17??C, 100% females), mixed-sex producing (24 and 25??C, 73.3 and 26.7% females, respectively), and masculinizing (29??C, 0% females) temperatures. The deduced cyp19A1 amino acid sequence shared high identity (>77.8%) with that from other teleosts but had low identity (sex producing temperatures were bimodal rather than intermediate, showing low and high modal values similar to those at the feminizing and masculinizing temperatures, respectively. The population percentages of high and low expression levels at intermediate temperatures were proportional to the percentage of females and males, respectively, and high levels were first observed at about the time of sex differentiation of females. These results suggest that cyp19A1 is involved in the process of ovarian formation and possibly also in the TSD of pejerrey. ?? 2007 Wiley-Liss, Inc.

  1. Effect of Yikun Neiyi Wan on the Expression of Aromatase P450,COX-2, and ER Related Receptor in Endometrial Cells in Vitro from Patients with Endometriosis

    Institute of Scientific and Technical Information of China (English)

    WANG Qing; ZHAO Hong; XIANG Qing; JU Hai; HAN Shu-min; WANG Ling-yan; XU Bo

    2009-01-01

    Objective: To investigate the effect of Yikun Neiyi Wan (益坤内异丸 YKNYW) and gestrinone on the expression of aromatase P450 (P450arom), cyclo-oxygenase-2 (COX-2) and estrogen receptor (ER) in isolated ectopic and normal endometrial stroma cells in vitro. Methods: Digestion and serial filtration were used to isolate and culture the ectopic and eutopic endometrial cells from patients with chocolate cyst in virto. Transformation of the cell morphology was observed in a inverted microscope. The effect of YKNYW on the expression of aromatase P450, cyclo-oxygenase-2, estrogen receptor in cultured endometriosis cells were detected by immunohistochemical method. Results: The expression levels of P450arom, COX-2 in glandular epithelium cells in vitro were decreased significantly by YKNYW compared with gestrinone (P<0.05). ER expression in mesenchymal cells of endometriosis was increased by YKNYW in the large and medium dosage groups compared with gestrinone. Conclusion: The mechanism by which YKNYW alleviates endometriosis pain is possibly related to the decrease in ectopic endometrial P450 arom and COX-2 expression in glandular epithelium, contrary to gestrinone, and the increase in ER expression in mesenchymalis, consistent with gestrione in patients with endometriosis.

  2. Factors Affecting MoO4(2-) Inhibitor Release from Zn2Al Based Layered Double Hydroxide and Their Implication in Protecting Hot Dip Galvanized Steel by Means of Organic Coatings.

    Science.gov (United States)

    Shkirskiy, V; Keil, P; Hintze-Bruening, H; Leroux, F; Vialat, P; Lefèvre, G; Ogle, K; Volovitch, P

    2015-11-18

    Zn2Al/-layered double hydroxide (LDH) with intercalated MoO4(2-) was investigated as a potential source of soluble molybdate inhibitor in anticorrosion coatings for hot dip galvanized steel (HDG). The effect of solution pH, soluble chlorides, and carbonates on the release kinetics of the interleaved MoO4(2-) ions from the LDH powder immersed in solutions containing different anions was studied by X-ray diffraction, in situ attenuated total reflectance infrared (ATR-IR) spectroscopy, and inductively coupled plasma atomic emission spectroscopy (ICP-AES). The effect of the solution composition on the total release and the release kinetics was demonstrated. Less than 30% of the total amount of the intercalated MoO4(2-) was released after 24 h of the immersion in neutral 0.005-0.5 M NaCl and 0.1 M NaNO3 solutions whereas the complete release of MoO4(2-) was observed after 1 h in 0.1 M NaHCO3 or Na2SO4 and in alkaline solutions. The in situ ATR-IR experiments and quantification of the released soluble species by ICP-AES demonstrated the release by an anion exchange in neutral solutions and by the dissolution of Zn2Al/-LDH in alkaline solutions. The anion exchange kinetics with monovalent anions was described by the reaction order n = 0.35 ± 0.05 suggesting the diffusion control; for divalent anions, n = 0.70 ± 0.06 suggested the control by a surface reaction. Dissolution of Zn from coated HDG with and without Zn2Al/-MoO4(2-) fillers, leaching of MoO4(2-) from the coating, and the electrochemical impedance spectroscopy response of the coated systems were measured during the immersion in 0.5 M NaCl solutions with and without 0.1 M NaHCO3. Without carbonates, the release of soluble MoO4(2-) was delayed for 24 h with no inhibiting effect whereas with 0.1 M NaHCO3 the immediate release was accompanied by the immediate and strong inhibiting effect on Zn dissolution. The concept of controlling the inhibition performance of LDH hybrid coatings by means of the environment

  3. The preferential nNOS inhibitor 7-nitroindazole and the non-selective one N(G)-nitro-L-arginine methyl ester administered alone or jointly with L-DOPA differentially affect motor behavior and monoamine metabolism in sham-operated and 6-OHDA-lesioned rats.

    Science.gov (United States)

    Czarnecka, Anna; Konieczny, Jolanta; Lenda, Tomasz; Lorenc-Koci, Elżbieta

    2015-11-01

    Reciprocal interactions between nitrergic and dopaminergic systems play a key role in the control of motor behavior. In the present study, we performed a comparative analysis of motor behavior (locomotor activity, catalepsy, rotational behavior) and monoamine metabolism in the striatum and substantia nigra of unilaterally sham-operated and 6-OHDA-lesioned rats treated with the preferential neuronal nitric oxide synthase (nNOS) inhibitor 7-nitroindazole (7-NI) or the non-selective one N(G)-nitro-L-arginine methyl ester (L-NAME), alone or in combination with L-DOPA. Each NOS inhibitor given alone (50mg/kg) induced a distinct catalepsy 30 min after injection but only 7-NI impaired spontaneous locomotion after 10 min. In 6-OHDA-lesioned rats, chronic L-DOPA (25mg/kg) induced 2.5-h long contralateral rotations. 7-NI (30 and 50mg/kg) markedly reduced the intensity of L-DOPA-induced contralateral rotations while extending their duration until 4.5h whereas L-NAME (50 and 100mg/kg) only tended to attenuate their intensity without affecting the duration. 7-NI but not L-NAME significantly increased endogenous tissue DA levels in the nigrostriatal system of both sham-operated and 6-OHDA-lesioned rats. In L-DOPA-treated group, 7-NI significantly enhanced the L-DOPA-derived tissue DA content in this system and decreased the level of the intracellular DA metabolite DOPAC produced by monoamine oxidase (MAO). In contrast to 7-NI, L-NAME decreased markedly DA content and did not affect DOPAC level in the ipsilateral striatum. It means that the differences in 7-NI and L-NAME-mediated modulation of L-DOPA-induced behavioral and biochemical effects resulted not only from the inhibition of NOS activity but also from differences in their ability to inhibit MAO. PMID:26319690

  4. Low toxicity corrosion inhibitors

    International Nuclear Information System (INIS)

    This paper discusses the design and testing of low toxicity corrosion inhibitors. New chemistries have been investigated with respect to corrosion protection and impact on the marine environment. The resulting chemicals, while they are effective corrosion inhibitors, present significant improvements in terms of environmental properties over current products. The discussion includes results of the corrosion inhibition, toxicity, biodegradability and partitioning studies

  5. Dissociable effects of acetylcholinesterase inhibitors and phosphodiesterase type 5 inhibitors on object recognition memory: acquisition versus consolidation

    NARCIS (Netherlands)

    Prickaerts, L.; Sik, A.; Staay, van der F.J.; Vente, de J.; Blokland, A.

    2005-01-01

    Rationale Phosphodiesterase enzyme type 5 (PDE5) inhibitors and acetylcholinesterase (AChE) inhibitors have cognition-enhancing properties. However, it is not known whether these drug classes affect the same memory processes. Objective We investigated the memory-enhancing effects of the PDE5 inhibit

  6. Estrogen biosynthesis: Metabolism of [16, 16, 19-2H3] [19-3H]19-Oxoandrost-4-ene-3, 17-Dione (1) by placental microsomal aromatase

    International Nuclear Information System (INIS)

    Publication of our results showing that 2β-hydroxy-19-oxoandrost-4-ene-3, 17-dione is not an obligatory estrogen precursor, rekindled interest in the late stages of estrogen biosynthesis from (1) and particularly in the utilization of the required third mole of oxygen and of NADPH. To understand the scope of transformations of the 19-oxo (1), and eventually isolate and identify the [oxygenated-(1)] estrogen precursor, we investigated the metabolism of (1) by placental microsomal aromatase. The following new types of metabolites of (1) were discovered: a: [(1)+0]; b: 4,6-dien-3-one analogs of (1) and of 19-norandrogens; c: 19-norandrogens and d: [(19-norandrost-4-ene-3, 17-dione)+0]. Biosynthesis of estrogens will be discussed in the context of the new results

  7. A polymorphism at the 3'-UTR region of the aromatase gene defines a subgroup of postmenopausal breast cancer patients with poor response to neoadjuvant letrozole

    Directory of Open Access Journals (Sweden)

    Albaladejo Carlos

    2010-02-01

    Full Text Available Abstract Background Aromatase (CYP19A1 regulates estrogen biosynthesis. Polymorphisms in CYP19A1 have been related to the pathogenesis of breast cancer (BC. Inhibition of aromatase with letrozole constitutes the best option for treating estrogen-dependent BC in postmenopausal women. We evaluate a series of polymorphisms of CYP19A1 and their effect on response to neoadjuvant letrozole in early BC. Methods We analyzed 95 consecutive postmenopausal women with stage II-III ER/PgR [+] BC treated with neoadjuvant letrozole. Response to treatment was measured by radiology at 4th month by World Health Organization (WHO criteria. Three polymorphisms of CYP19A1, one in exon 7 (rs700519 and two in the 3'-UTR region (rs10046 and rs4646 were evaluated on DNA obtained from peripheral blood. Results Thirty-five women (36.8% achieved a radiological response to letrozole. The histopathological and immunohistochemical parameters, including hormonal receptor status, were not associated with the response to letrozole. Only the genetic variants (AC/AA of the rs4646 polymorphism were associated with poor response to letrozole (p = 0.03. Eighteen patients (18.9% reported a progression of the disease. Those patients carrying the genetic variants (AC/AA of rs4646 presented a lower progression-free survival than the patients homozygous for the reference variant (p = 0.0686. This effect was especially significant in the group of elderly patients not operated after letrozole induction (p = 0.009. Conclusions Our study reveals that the rs4646 polymorphism identifies a subgroup of stage II-III ER/PgR [+] BC patients with poor response to neoadjuvant letrozole and poor prognosis. Testing for the rs4646 polymorphism could be a useful tool in order to orientate the treatment in elderly BC patients.

  8. Cricothyroidotomy in a angiotensin-converting enzyme (ACE Inhibitor tongue´s angioedema.

    Directory of Open Access Journals (Sweden)

    Acle-Cervera L, Morales-Angulo C, García-Zornoza R, Rubio Suárez A

    2013-01-01

    Full Text Available Hereditary angioedema by inhibitors of Angiotensin Converting Enzyme(ACE is a very rare disorder. It usually affects the upper airway mucosa andproduce rapidly evolving acute exacerbations requiring urgent treatment.We repost the case of a patient being treated with ACE inhibitors and anreview of prevalence, pathophysiology and management of angioedemawith ACE inhibitors for treatment and the latest treatments.

  9. Proteasome inhibitor treatment in alcoholic liver disease

    Institute of Scientific and Technical Information of China (English)

    Fawzia Bardag-Gorce

    2011-01-01

    Oxidative stress, generated by chronic ethanol consumption, is a major cause of hepatotoxicity and liver injury. Increased production of oxygen-derived free radicals due to ethanol metabolism by CYP2E1 is principally located in the cytoplasm and in the mitochondria, which does not only injure liver cells, but also other vital organs, such as the heart and the brain. Therefore, there is a need for better treatment to enhance the antioxidant response elements. To date, there is no established treatment to attenuate high levels of oxidative stress in the liver of alcoholic patients. To block this oxidative stress, proteasome inhibitor treatment has been found to significantly enhance the antioxidant response elements of hepatocytes exposed to ethanol. Recent studies have shown in an experimental model of alcoholic liver disease that proteasome inhibitor treatment at low dose has cytoprotective effects against ethanol-induced oxidative stress and liver steatosis. The beneficial effects of proteasome inhibitor treatment against oxidative stress occurred because antioxidant response elements (glutathione peroxidase 2, superoxide dismutase 2, glutathione synthetase, glutathione reductase, and GCLC) were upregulated when rats fed alcohol were treated with a low dose of PS-341 (Bortezomib, Velcade(r)). This is an important finding because proteasome inhibitor treatment up-regulated reactive oxygen species removal and glutathione recycling enzymes, while ethanol feeding alone down-regulated these antioxidant elements. For the first time, it was shown that proteasome inhibition by a highly specific and reversible inhibitor is different from the chronic ethanol feeding-induced proteasome inhibition. As previously shown by our group, chronic ethanol feeding causes a complex dysfunction in the ubiquitin proteasome pathway, which affects the proteasome system, as well as the ubiquitination system. The beneficial effects of proteasome inhibitor treatment in alcoholic liver disease

  10. Small-molecule caspase inhibitors

    International Nuclear Information System (INIS)

    The review considers low-molecular weight inhibitors of caspases, cysteine proteases being key contributors to apoptosis (programmed cell death). The inhibitors with aspartic acid residues or various heterocyclic systems (both synthetic and natural) are covered. Their possible mechanisms of action are discussed. Data on inhibitor structure-activity relationship studies are systematically surveyed. The interactions of the non-peptide fragments of an inhibitor with the enzymes are examined. Examples of the use of some inhibitors for apoptosis suppression are provided.

  11. Small-molecule caspase inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Zhenodarova, S M [Institute for Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino, Moscow region (Russian Federation)

    2010-02-28

    The review considers low-molecular weight inhibitors of caspases, cysteine proteases being key contributors to apoptosis (programmed cell death). The inhibitors with aspartic acid residues or various heterocyclic systems (both synthetic and natural) are covered. Their possible mechanisms of action are discussed. Data on inhibitor structure-activity relationship studies are systematically surveyed. The interactions of the non-peptide fragments of an inhibitor with the enzymes are examined. Examples of the use of some inhibitors for apoptosis suppression are provided.

  12. Small-molecule caspase inhibitors

    Science.gov (United States)

    Zhenodarova, S. M.

    2010-02-01

    The review considers low-molecular weight inhibitors of caspases, cysteine proteases being key contributors to apoptosis (programmed cell death). The inhibitors with aspartic acid residues or various heterocyclic systems (both synthetic and natural) are covered. Their possible mechanisms of action are discussed. Data on inhibitor structure-activity relationship studies are systematically surveyed. The interactions of the non-peptide fragments of an inhibitor with the enzymes are examined. Examples of the use of some inhibitors for apoptosis suppression are provided.

  13. Affect Regulation

    DEFF Research Database (Denmark)

    Pedersen, Signe Holm; Poulsen, Stig Bernt; Lunn, Susanne

    2014-01-01

    Gergely and colleagues’ state that their Social Biofeedback Theory of Parental Affect Mirroring” can be seen as a kind of operationalization of the classical psychoanalytic concepts of holding, containing and mirroring. This article examines to what extent the social biofeedback theory of parenta...

  14. Synergistic apoptosis induction in leukemic cells by the phosphatase inhibitor salubrinal and proteasome inhibitors.

    Directory of Open Access Journals (Sweden)

    Hannes C A Drexler

    Full Text Available BACKGROUND: Cells adapt to endoplasmic reticulum (ER-stress by arresting global protein synthesis while simultaneously activating specific transcription factors and their downstream targets. These processes are mediated in part by the phosphorylation-dependent inactivation of the translation initiation factor eIF2alpha. Following restoration of homeostasis protein synthesis is resumed when the serine/threonine-protein phosphatase PP1 dephosphorylates and reactivates eIF2alpha. Proteasome inhibitors, used to treat multiple myeloma patients evoke ER-stress and apoptosis by blocking the ER-associated degradation of misfolded proteins (ERAD, however, the role of eIF2alpha phosphorylation in leukemic cells under conditions of proteasome inhibitor-mediated ER stress is currently unclear. METHODOLOGY AND PRINCIPAL FINDINGS: Bcr-Abl-positive and negative leukemic cell lines were used to investigate the functional implications of PP1-related phosphatase activities on eIF2alpha phosphorylation in proteasome inhibitor-mediated ER stress and apoptosis. Rather unexpectedly, salubrinal, a recently identified PP1 inhibitor capable to protect against ER stress in various model systems, strongly synergized with proteasome inhibitors to augment apoptotic death of different leukemic cell lines. Salubrinal treatment did not affect the phosphorlyation status of eIF2alpha. Furthermore, the proapoptotic effect of salubrinal occurred independently from the chemical nature of the proteasome inhibitor, was recapitulated by a second unrelated phosphatase inhibitor and was unaffected by overexpression of a dominant negative eIF2alpha S51A variant that can not be phosphorylated. Salubrinal further aggravated ER-stress and proteotoxicity inflicted by the proteasome inhibitors on the leukemic cells since characteristic ER stress responses, such as ATF4 and CHOP synthesis, XBP1 splicing, activation of MAP kinases and eventually apoptosis were efficiently abrogated by the

  15. Cholinesterase inhibitors from botanicals

    Directory of Open Access Journals (Sweden)

    Faiyaz Ahmed

    2013-01-01

    Full Text Available Alzheimer′s disease (AD is a progressive neurodegenerative disease, wherein a progressive loss of cholinergic synapses occurs in hippocampus and neocortex. Decreased concentration of the neurotransmitter, acetylcholine (ACh, appears to be critical element in the development of dementia, and the most appropriate therapeutic approach to treat AD and other form of dementia is to restore acetylcholine levels by inhibiting both major form of cholinesterase: Acetylcholinesterase (AChE and butyrylcholinesterase (BChE. Consequently, researches have focused their attention towards finding cholinesterase inhibitors from natural products. A large number of such inhibitors have been isolated from medicinal plants. This review presents a comprehensive account of the advances in field of cholinesterase inhibitor phytoconstituents. The structures of some important phytoconstituents (collected through www.Chemspider.com are also presented and the scope for future research is discussed.

  16. Phosphodiesterase-5 inhibitors.

    Science.gov (United States)

    Cockrill, Barbara A; Waxman, Aaron B

    2013-01-01

    Nitric oxide (NO) signaling plays a key role in modulating vascular tone and remodeling in the pulmonary circulation. The guanylate cyclase/cyclic guanylate monophosphate-signaling pathway primarily mediates nitric oxide signaling. This pathway is critical in normal regulation of the pulmonary vasculature, and is an important target for therapy in patients with pulmonary hypertension. In the pulmonary vasculature, degradation of cGMP is primarily regulated by PDE-5, and inhibition of this enzyme has important effects on pulmonary vasculature smooth muscle tone. Large randomized placebo-controlled trials of PDE-5 inhibitors demonstrated improved exercise capacity, hemodynamics and quality of life in adult patients with PAH. This chapter will discuss the mechanisms of NO signaling in the vasculature, characteristics of the PDE5-inhibitors approved for treatment of PH, and review available data on the use of phosphodiesterase inhibitors in PH. PMID:24092343

  17. Cytochrome p450 inhibitory properties of common efflux transporter inhibitors.

    Science.gov (United States)

    Englund, Gunilla; Lundquist, Patrik; Skogastierna, Cristine; Johansson, Jenny; Hoogstraate, Janet; Afzelius, Lovisa; Andersson, Tommy B; Projean, Denis

    2014-03-01

    Drug transporter inhibitors are important tools to elucidate the contribution of transporters to drug disposition both in vitro and in vivo. These inhibitors are often unselective and affect several transporters as well as drug metabolizing enzymes, which can make experimental results difficult to interpret with confidence. We therefore tested 14 commonly used P-glycoprotein (P-gp), breast cancer resistance protein (BCRP), and multidrug-resistance associated protein (MRP) inhibitors as inhibitors of cytochrome P450 (P450) enzyme activities using recombinant enzymes. A subset of P-gp and/or CYP3A inhibitors were selected (cyclosporin A, elacridar, ketoconazole, quinidine, reserpine, and tacrolimus) for a comparison of P450 inhibition in human microsomes and hepatocytes. Most P-gp inhibitors showed CYP3A4 inhibition, with potencies often in a similar range as their P-gp inhibition, as well as less potent CYP2C19 inhibition. Other P450 enzymes were not strongly inhibited except a few cases of CYP2D6 inhibition. MRP and BCRP inhibitors showed limited P450 inhibition. Some inhibitors showed less P450 inhibition in human hepatocytes than human liver microsomes, for example, elacridar, probably due to differences in binding, permeability limitations, or active, P-gp mediated efflux of the inhibitor from the hepatocytes. Quinidine was a potent P450 inhibitor in hepatocytes but only showed weak inhibition in microsomes. Quinidine shows an extensive cellular uptake, which may potentiate intracellular P450 inhibition. Elacridar, described as a potent and selective P-gp inhibitor, displayed modest P450 inhibition in this study and is thus a useful model inhibitor to define the role of P-gp in drug disposition without interference with other processes. PMID:24396142

  18. Affective Urbanism

    DEFF Research Database (Denmark)

    Samson, Kristine

    , experience and consumption are all strategic design tools applied by planners and architects. Whereas urban design in former modernist planning served merely functional or political means, urban design has increasingly become an aesthetical mediator of ideologies embedded in the urban field of life forces...... capitalism not only changes urban life and its means of production, it specifically influences the way the city is designed and how it unfolds as events (Anderson & Harrison 2010) and affective, emotional production (Pile 2009). Through examples of urban design and events in the Carlsberg City in Copenhagen...... and The High Line in Chelsea, New York, the paper sets out to define and question these affective modes of production. Whether these productions are socio-material practices consisting of ludic designs (Stevens 2007), temporary architecture or art installations or evental practices consisting of...

  19. Estrogen receptor and aromatase expression in gingival carcinoma tissue%雌激素受体及芳香化酶在牙龈癌组织中的表达和意义

    Institute of Scientific and Technical Information of China (English)

    王秋锐; 杨健; 赵华平; 张英怀

    2015-01-01

    AIM:To investigate the expression of estrogen receptor (ER)and aromatase in gingival carcino-ma.METHODS:ER and aromatase were detected by immunohistochemical staining SP method in gingival carcinoma (n=28)and normal gingival tissues(n=15).RESULTS:Positive expression rates of ER and aromatase expression in gingival carcinoma were 50.00% and 42.86% ,in normal gingival tissues were 13.33% and 6.67%,respectively (P<0.05).No significant correlation was found between ER and aromatase in gingival carcinoma.CONCLUSION:Estrogen metablism might be related to gingival carcinoma.Aromatase is not the exclusive reason of the high positive rate of ER.%目的:观察牙龈癌中雌激素受体(ER)与芳香化酶的表达情况,探讨局部雌激素及芳香化酶在牙龈癌中的作用与关系。方法:免疫组化过氧化物酶标记的链酶卵白素法测定雌激素受体及芳香化酶在牙龈癌中的表达。结果:牙龈癌组雌激素受体及芳香化酶的表达阳性率分别为50%和42.86%,正常对照组分别为13.33%和6.67%(P<0.05);牙龈癌中雌激素受体与芳香化酶之间未见明显相关性。结论:牙龈癌有一定的雌激素依赖性;芳香化酶在牙龈癌组织中表达升高,但芳香化酶并不是影响局部雌激素受体升高的唯一因素。

  20. Prostaglandin Inhibitors: Rational Therapy for Dysmenorrhea

    OpenAIRE

    Sorbie, Janet

    1982-01-01

    Dysmenorrhea affects at least 50% of women at some time in their lives. Painful contractions of the uterine muscle (similar to labor pains) are triggered by increased endometrial synthesis of prostaglandins, which appear in elevated amounts in the plasma and menstrual fluid of women with dysmenorrhea. Non-steroidal anti-inflammatory drugs, which have been used for years in arthritis, are effective prostaglandin inhibitors. Taken by mouth at the onset of menstruation, they can relieve dysmenor...

  1. Protein protease inhibitors in insects and comparison with mammalian inhibitors.

    Science.gov (United States)

    Eguchi, M

    1993-01-01

    1. Studies on insect protein protease inhibitors are summarized. Biochemical, genetic and physiological investigations of the silkworm are performed. 2. In addition, the properties and characteristics of fungal protease inhibitors from the silkworm (Bombyx mori) are described and their importance as defensive functions is emphasized. 3. This review also concerns comparative and evolutionary studies of protease inhibitors from various sources. 4. The biological significance of inhibitors is discussed in view of the extensive experimental results. PMID:8365101

  2. Corrosion inhibitor compositions

    International Nuclear Information System (INIS)

    A corrosion inhibitor compositon for hydrocarbon fuels consisting essentially of, by weight, (A) about 75% to 95% of at least one polymerized unsaturated aliphatic monocarboxylic acid, said unsaturated acid having 16 to 18 carbons per molecule, and (B) about 5% to 25% of at least one monoalkenylsuccinic acid in which the alkenyl group as 8 to 18 carbons

  3. Thymidine Phosphorylase Inhibitors

    Czech Academy of Sciences Publication Activity Database

    Nencka, Radim

    Karachi : Bentham Science Publishers, 2011 - (Atta-ur-Rahman, F.; Choudhary, M.), s. 116-147 ISBN 978-1-60805-162-5 R&D Projects: GA MŠk 1M0508; GA AV ČR 1QS400550501 Institutional research plan: CEZ:AV0Z40550506 Keywords : thymidine phosphorylase inhibitors * angiogenesis * cancer chemotherapy Subject RIV: CC - Organic Chemistry

  4. Sunflower trypsin inhibitor-1.

    Science.gov (United States)

    Korsinczky, Michael L J; Schirra, Horst Joachim; Craik, David J

    2004-10-01

    SFTI-1 is a bicyclic 14 amino acid peptide that was originally isolated from the seeds of the sunflower Helianthus annuus. It is a potent inhibitor of trypsin, with a sub-nanomolar K(i) value and is homologous to the active site region of the well-known family of serine protease inhibitors known as the Bowman-Birk trypsin inhibitors. It has a cyclic backbone that is cross-braced by a single disulfide bridge and a network of hydrogen bonds that result in a well-defined structure. SFTI-1 is amenable to chemical synthesis, allowing for the creation of synthetic variants. Alterations to the structure such as linearising the backbone or removing the disulfide bridge do not reduce the potency of SFTI-1 significantly, and minimising the peptide to as few as nine residues results in only a small decrease in reactivity. The creation of linear variants of SFTI-1 also provides a tool for investigating putative linear precursor peptides. The mechanism of biosynthesis of SFTI-1 is not yet known but it seems likely that it is a gene-coded product that has arisen from a precursor protein that may be evolutionarily related to classic Bowman-Birk inhibitors. PMID:15544530

  5. Inhibitors of histone demethylases

    DEFF Research Database (Denmark)

    Lohse, Brian; Kristensen, Jesper L; Kristensen, Line H; Agger, Karl; Helin, Kristian; Gajhede, Michael; Clausen, Rasmus P

    2011-01-01

    Methylated lysines are important epigenetic marks. The enzymes involved in demethylation have recently been discovered and found to be involved in cancer development and progression. Despite the relative recent discovery of these enzymes a number of inhibitors have already appeared. Most of the...

  6. Affective Maps

    DEFF Research Database (Denmark)

    Salovaara-Moring, Inka

    Recently, in human geography there has been a considerable attention paid to retheorising maps; less as a product and more as practice. This refers to the notion that rather than reading maps as fixed representations, digital mapping is by nature a dynamic, performative, and participatory practice....... In particular, mapping environmental damage, endangered species, and human made disasters has become one of the focal point of affective knowledge production. These ‘more-than-humangeographies’ practices include notions of species, space and territory, and movement towards a new political ecology...

  7. Inhibition of matrix metalloproteinase-2 by PARP inhibitors

    OpenAIRE

    Nicolescu, Adrian C.; Holt, Andrew; Kandasamy, Arulmozhi D.; Pacher, Pal; Schulz, Richard

    2009-01-01

    Matrix metalloproteinase-2 (MMP-2), a ubiquitously expressed zinc-dependent endopeptidase, and poly(ADP-ribosyl) polymerase (PARP), a nuclear enzyme regulating DNA repair, are activated by nitroxidative stress associated with various pathologies. As MMP-2 plays a detrimental role in heart injuries resulting from enhanced nitroxidative stress, where PARP and MMP inhibitors are beneficial, we hypothesized that PARP inhibitors may affect MMP-2 activity. Using substrate degradation assays to dete...

  8. Procedure to Determine Enzyme Inhibitors Activity in Cereal Seeds

    OpenAIRE

    Fernanda Arnhold Pagnussatt; Silvia Letícia Rivero Meza; Jaqueline Garda-Buffon; Eliana Badiale-Furlong

    2012-01-01

    This work established a procedure for commercial fungal amylase usage as indicator of enzyme inhibitors presence in cereals, intending to screening antifungal resistance properties in cereals. Firstly, the inhibitive effects of oat, wheat and rice protein extracts were assessed against different amylase sources. It was found that the fungal amylase (Fungamyl®) was the most affected by the inhibition property of the extracts. The best conditions for inhibitor-extract-enzyme interaction were es...

  9. Chronic green tea consumption decreases body mass, induces aromatase expression, and changes proliferation and apoptosis in adult male rat adipose tissue.

    Science.gov (United States)

    Monteiro, Rosário; Assunção, Marco; Andrade, José P; Neves, Delminda; Calhau, Conceição; Azevedo, Isabel

    2008-11-01

    Green tea (GT) and its components have been shown to possess antiobesity properties and the corresponding mechanisms of action are being investigated, given the epidemic proportions of obesity incidence. In the current work, we used 12-mo-old male Wistar rats to test the effect of 6 mo of treatment with GT as the sole drinking beverage (52.8 +/- 6.4 mL/d) on adipose tissue (AT). AT aromatase expression was determined by Western blotting, plasma concentrations of 17beta-estradiol and testosterone were determined by RIA, and adipocyte size determined by measuring diameter in tissue sections. Proliferation and apoptosis were also assessed by Ki67 immunostaining and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labeling, respectively. Evaluations were made in subcutaneous (sc) AT and visceral (v) AT. Body weight increased over time in both groups (P rats had a higher percentage of proliferating cells (204.1 +/- 19.5% of control in scAT, P adipocytes (78.3 +/- 1.7% of control in scAT, P < 0.001, and 87.9 +/- 3.2% of control in vAT, P < 0.05). GT also increased the number of apoptotic cells in vAT (320.4 +/- 21.9% of control; P < 0.001). These results suggest new mechanisms for GT on body weight and highlight its potential benefit to prevent or treat obesity and the metabolic syndrome. PMID:18936213

  10. [Affective dependency].

    Science.gov (United States)

    Scantamburlo, G; Pitchot, W; Ansseau, M

    2013-01-01

    Affective dependency is characterized by emotional distress (insecure attachment) and dependency to another person with a low self-esteem and reassurance need. The paper proposes a reflection on the definition of emotional dependency and the confusion caused by various denominations. Overprotective and authoritarian parenting, cultural and socio-environmental factors may contribute to the development of dependent personality. Psychological epigenetic factors, such as early socio-emotional trauma could on neuronal circuits in prefronto-limbic regions that are essential for emotional behaviour.We also focus on the interrelations between dependent personality, domestic violence and addictions. The objective for the clinician is to propose a restoration of self-esteem and therapeutic strategies focused on autonomy. PMID:23888587

  11. Bu-Shen-Ning-Xin Decoction ameliorated the osteoporotic phenotype of ovariectomized mice without affecting the serum estrogen concentration or uterus

    Directory of Open Access Journals (Sweden)

    Wang L

    2015-08-01

    Full Text Available Ling Wang,1,2,* Xue-Min Qiu,1,2,* Yu-Yan Gui,1,2 Ying-Ping Xu,1,2 Hans-Jürgen Gober,3 Da-Jin Li1 1Laboratory for Reproductive Immunology, Hospital and Institute of Obstetrics and Gynecology, IBS, Fudan University Shanghai Medical College, 2Shanghai Key Laboratory of Female Reproductive Endocrine Related Diseases, Shanghai, People’s Republic of China; 3Department of Pharmacy, Wagner Jauregg Hospital and Children’s Hospital, Linz, Austria *These authors contributed equally to this work Introduction: Bu-Shen-Ning-Xin Decoction (BSNXD, a traditional Chinese medicinal composition, has been used as a remedy for postmenopausal osteoporosis, but its effects on bone metabolism and the uterus have not been reported.Purpose: We aimed to determine the respective effects of BSNXD on the bones and the uterus of ovariectomized (OVX mice to evaluate the efficacy and safety of this herbal formula.Materials and methods: Postmenopausal osteoporosis animal models that were generated by ovariectomy were treated with BSNXD. Dual-energy X-ray absorptiometry was performed to analyze the bone mineral density, and histomorphometric analysis was performed to measure the parameters related to bone metabolism. Calcein labeling was performed to detect bone formation. The uteruses from the mice were weighed, and the histomorphometry was analyzed. Drug-derived serum was prepared to assess the 17-β-estradiol concentration via enzyme immunoassay.Results: BSNXD administration ameliorated the osteoporotic phenotype of OVX mice, as evidenced by an increase in the bone mineral density and bone volume; these effects could not be abolished by the administration of the aromatase inhibitor letrozole. Moreover, BSNXD had no effect on the serum estrogen concentration or uterus.Conclusion: These results suggest that BSNXD has ameliorating effects on bone loss due to estrogen deprivation without affecting the peripheral blood estrogen concentration or the uterus in OVX mice. Keywords

  12. A chemotactic inhibitor in synovial fluid.

    Science.gov (United States)

    Matzner, Y; Partridge, R E; Babior, B M

    1983-01-01

    Synovial fluid was found to contain an inhibitor of neutrophil chemotaxis. The activity of this inhibitor was masked in native synovial fluid, but could be detected in fluid in which complement had been deactivated by mild heating. The inhibitor was most effective against the chemotactic activity of zymosan-activated serum (C5ades arg). It had little effect when N-formyl-methionyl-leucyl-phenylalanine served as chemoattractant. Inhibition was not the result of a direct effect on the neutrophils, since incubation of cells with synovial fluid did not alter their chemotactic response. The inhibitory activity was destroyed by boiling the synovial fluid or treating it with trypsin, suggesting that it is a protein (or proteins); it was not affected by hyaluronidase treatment. Gel filtration revealed that the inhibitor was present in native as well as decomplemented synovial fluid, and that its molecular weight was in the vicinity of 25,000. It is proposed that this inhibitory activity plays a role in the regulation of the inflammatory response in joints. PMID:6840801

  13. Cellular growth kinetics distinguish a cyclophilin inhibitor from an HSP90 inhibitor as a selective inhibitor of hepatitis C virus.

    Directory of Open Access Journals (Sweden)

    Rudolf K F Beran

    Full Text Available During antiviral drug discovery, it is critical to distinguish molecules that selectively interrupt viral replication from those that reduce virus replication by adversely affecting host cell viability. In this report we investigate the selectivity of inhibitors of the host chaperone proteins cyclophilin A (CypA and heat-shock protein 90 (HSP90 which have each been reported to inhibit replication of hepatitis C virus (HCV. By comparing the toxicity of the HSP90 inhibitor, 17-(Allylamino-17-demethoxygeldanamycin (17-AAG to two known cytostatic compounds, colchicine and gemcitabine, we provide evidence that 17-AAG exerts its antiviral effects indirectly through slowing cell growth. In contrast, a cyclophilin inhibitor, cyclosporin A (CsA, exhibited selective antiviral activity without slowing cell proliferation. Furthermore, we observed that 17-AAG had little antiviral effect in a non-dividing cell-culture model of HCV replication, while CsA reduced HCV titer by more than two orders of magnitude in the same model. The assays we describe here are useful for discriminating selective antivirals from compounds that indirectly affect virus replication by reducing host cell viability or slowing cell growth.

  14. [JAK2 inhibitors].

    Science.gov (United States)

    Hernández Boluda, Juan Carlos; Gómez, Montse; Pérez, Ariadna

    2016-07-15

    Pharmacological inhibition of the kinase activity of JAK proteins can interfere with the signaling of immunomodulatory cytokines and block the constitutive activation of the JAK-STAT pathway that characterizes certain malignancies, including chronic myeloproliferative neoplasms. JAK inhibitors may, therefore, be useful to treat malignancies as well as inflammatory or immune disorders. Currently, the most significant advances have been made in the treatment of myelofibrosis, where these drugs may lead to a remarkable improvement in the control of hyperproliferative manifestations. However, available data suggest that this treatment is not curative of myelofibrosis. In general, JAK2 inhibition induces cytopaenias, with this being considered a class side-effect. By contrast, the extrahaematologic toxicity profile varies significantly among the different JAK inhibitors. At present, there are several clinical trials evaluating the combination of ruxolitinib with other drugs, in order to improve its therapeutic activity as well as reducing haematologic toxicity. PMID:27033437

  15. Benzoylurea Chitin Synthesis Inhibitors.

    Science.gov (United States)

    Sun, Ranfeng; Liu, Chunjuan; Zhang, Hao; Wang, Qingmin

    2015-08-12

    Benzoylurea chitin synthesis inhibitors are widely used in integrated pest management (IPM) and insecticide resistance management (IRM) programs due to their low toxicity to mammals and predatory insects. In the past decades, a large number of benzoylurea derivatives have been synthesized, and 15 benzoylurea chitin synthesis inhibitors have been commercialized. This review focuses on the history of commercial benzolyphenylureas (BPUs), synthetic methods, structure-activity relationships (SAR), action mechanism research, environmental behaviors, and ecotoxicology. Furthermore, their disadvantages of high risk to aquatic invertebrates and crustaceans are pointed out. Finally, we propose that the para-substituents at anilide of benzoylphenylureas should be the functional groups, and bipartite model BPU analogues are discussed in an attempt to provide new insight for future development of BPUs. PMID:26168369

  16. Alpha glucosidase inhibitors.

    Science.gov (United States)

    Kalra, Sanjay

    2014-04-01

    Alpha glucosidase inhibitors (AGIs) are a unique class of anti-diabetic drugs. Derived from bacteria, these oral drugs are enzyme inhibitors which do not have a pancreato -centred mechanism of action. Working to delay carbohydrate absorption in the gastrointestinal tract, they control postprandial hyperglycaemia and provide unquestioned cardiovascular benefit. Specially suited for a traditional Pakistani carbohydrate-rich diet, AGIs have been termed the 'untapped diamonds' of diabetology. The use of these oral antidiabetic drugs (OADs) that target pathophysiology in the early stages of type 2 diabetes, notably to reduce postprandial hyperglycaemia and hyperinsulinaemia will inevitably increase with time. This review describes the history of their development, mechanism of action, basic and clinical pharmacology, and suggests practical, evidence-based guidance for their optimal use. PMID:24864650

  17. Dual effects of phytoestrogens result in u-shaped dose-response curves

    DEFF Research Database (Denmark)

    Almstrup, Kristian; Fernández, Mariana F; Petersen, Jørgen H;

    2002-01-01

    Endocrine disruptors can affect the endocrine system without directly interacting with receptors, for example, by interfering with the synthesis or metabolism of steroid hormones. The aromatase that converts testosterone to 17beta-estradiol is a possible target. In this paper we describe an assay...... that simultaneously detects aromatase inhibition and estrogenicity. The principle is similar to that of other MCF-7 estrogenicity assays, but with a fixed amount of testosterone added. The endogenous aromatase activity in MCF-7 cells converts some of the testosterone to 17beta-estradiol, which is assayed...... by quantifying differences in the expression level of the estrogen-induced pS2 mRNA. Potential aromatase inhibitors can be identified by a dose-dependent reduction in the pS2 mRNA expression level after exposure to testosterone and the test compound. Using this assay, we have investigated several compounds...

  18. How does real affect affect affect recognition in speech?

    NARCIS (Netherlands)

    Truong, Khiet Phuong

    2009-01-01

    The aim of the research described in this thesis was to develop speech-based affect recognition systems that can deal with spontaneous (‘real’) affect instead of acted affect. Several affect recognition experiments with spontaneous affective speech data were carried out to investigate what combinati

  19. Secreted and transmembrane wnt inhibitors and activators.

    Science.gov (United States)

    Cruciat, Cristina-Maria; Niehrs, Christof

    2013-03-01

    Signaling by the Wnt family of secreted glycoproteins plays important roles in embryonic development and adult homeostasis. Wnt signaling is modulated by a number of evolutionarily conserved inhibitors and activators. Wnt inhibitors belong to small protein families, including sFRP, Dkk, WIF, Wise/SOST, Cerberus, IGFBP, Shisa, Waif1, APCDD1, and Tiki1. Their common feature is to antagonize Wnt signaling by preventing ligand-receptor interactions or Wnt receptor maturation. Conversely, the Wnt activators, R-spondin and Norrin, promote Wnt signaling by binding to Wnt receptors or releasing a Wnt-inhibitory step. With few exceptions, these antagonists and agonists are not pure Wnt modulators, but also affect additional signaling pathways, such as TGF-β and FGF signaling. Here we discuss their interactions with Wnt ligands and Wnt receptors, their role in developmental processes, as well as their implication in disease. PMID:23085770

  20. Naphthyridines as novel BET family bromodomain inhibitors.

    Science.gov (United States)

    Mirguet, Olivier; Lamotte, Yann; Chung, Chun-Wa; Bamborough, Paul; Delannée, Delphine; Bouillot, Anne; Gellibert, Françoise; Krysa, Gael; Lewis, Antonia; Witherington, Jason; Huet, Pascal; Dudit, Yann; Trottet, Lionel; Nicodeme, Edwige

    2014-03-01

    Bromodomains (BRDs) are small protein domains found in a variety of proteins that recognize and bind to acetylated histone tails. This binding affects chromatin structure and facilitates the localisation of transcriptional complexes to specific genes, thereby regulating epigenetically controlled processes including gene transcription and mRNA elongation. Inhibitors of the bromodomain and extra-terminal (BET) proteins BRD2-4 and T, which prevent bromodomain binding to acetyl-modified histone tails, have shown therapeutic promise in several diseases. We report here the discovery of 1,5-naphthyridine derivatives as potent inhibitors of the BET bromodomain family with good cell activity and oral pharmacokinetic parameters. X-ray crystal structures of naphthyridine isomers have been solved and quantum mechanical calculations have been used to explain the higher affinity of the 1,5-isomer over the others. The best compounds were progressed in a mouse model of inflammation and exhibited dose-dependent anti-inflammatory pharmacology. PMID:24000170

  1. PENGHAMBAT α AMILASE: JENIS, SUMBER, DAN POTENSI PEMANFAATANNYA DALAM KESEHATAN [α Amylase Inhibitors: Types, Sources, and Their Potential Utilization for Health Purposes

    OpenAIRE

    Budiasih Wahyuntari

    2011-01-01

    SUMMARYAlpha amylase inhibitors affect carbohydrate metabolism in digestive system. The inhibitors induce carbohydrate tolerance, fullness and prolonging gastric emptying that might be used to aid in diabetic and obesity treatment. There are two types of α- amylase inhibitors, proteinaceous and non-proteinaceous ones. Proteinaceous inhibitor is classified into seven classes including legumes, lectin, knottin, cereal, Kunitz, -thionin and thaumatin types. Plant proteinaceous inhibitors are pr...

  2. A syndrome of female pseudohermaphrodism, hypergonadotropic hypogonadism, and multicystic ovaries associated with missense mutations in the gene encoding aromatase (P450arom)

    Energy Technology Data Exchange (ETDEWEB)

    Conte, F.A.; Grumbach, M.M. [Univ. of California, San Francisco, CA (United States); Ito, Y.; Fisher, C.R.; Simpson, E.R. [Univ. of Texas Southwestern Medical Center, Dallas, TX (United States)

    1994-06-01

    The authors report the features of a new syndrome of aromatase deficiency due to molecular defects in the CYP19 (P450arom) gene in a 46,XX female. At birth, the patient presented with a nonadrenal form of female pseudohermaphrodism. At 17 months of age, laparotomy revealed normal female internal genital structures; the histological appearance of the ovaries was normal. FSH concentrations were markedly elevated at 9.4 ng/mL LER 869, and estrone and estradiol levels were undetectable (<37 pmol/L). By 14 yr of age, she had failed to exhibit breast development. The clitoris has enlarged to 4 x 2 cm, and pubic hair was Tanner stage IV. The plasma concentration of testosterone was elevated at 3294 pmol/L, as was androstenedione at 9951 pmol/L. Plasma estradiol levels were below 37 pmol/L. ACTH and dexamethasone tests indicated a nonadrenal source of testosterone and androstenedione. Plasma gonadotropin levels were in the castrate range. Pelvic sonography and magnetic resonance imaging showed multiple 4- to 6-cm ovarian cysts bilaterally. Despite increased circulating androgens and clitoral growth, the bone age was 10 yr at chronologic age 14 2/12 yr. Estrogen replacement therapy resulted in a growth spurt, breast development, menarche, suppression of gonadotropin levels, and resolution of the cysts. The clinical findings suggested the diagnosis of P450arom deficiency. Analyses of genomic DNA from ovarian fibroblasts demonstrated two single base changes in the coding region of the P450arom gene, one at 1303 basepairs (C-T), R435C, and the other at 1310 basepairs (G-A), C437Y, in exon 10. The molecular genetic studies indicate that the patient is a compound heterozygote for these mutations. Expression of these mutations showed that the R435C mutation had 1.1% the activity of the wild-type P450arom enzyme, whereas the C437Y mutation demonstrated no activity. 32 refs., 6 figs., 2 tabs.

  3. Between-female variation in house sparrow yolk testosterone concentration is negatively associated with CYP19A1 (aromatase) mRNA expression in ovarian follicles.

    Science.gov (United States)

    Egbert, Jeremy R; Jackson, Melissa F; Rodgers, Buel D; Schwabl, Hubert

    2013-03-01

    Maternally-derived yolk androgens influence the development and long-term phenotype of offspring in oviparous species. Between-female variation in the amounts of these yolk androgens has been associated with a number of social and environmental factors, suggesting that the variation is adaptive, but the mechanisms behind it are unknown. Using two different approaches, we tested the hypothesis that variation in yolk androgen levels across individuals is associated with variation in their capacity to synthesize androgens. First, we injected female house sparrows with exogenous gonadotropin-releasing hormone (GnRH) to maximally stimulate ovarian steroidogenesis. Second, we collected pre-ovulatory follicle tissue and quantified the mRNA expression of four key enzymes of the steroid synthesis pathway: steroidogenic acute regulatory protein (StAR), cytochrome P450-side chain cleavage enzyme (CYP11A1), 17β-hydroxysteroid dehydrogenase (HSD17B1), and aromatase (CYP19A1). Thirty minutes after GnRH injection, androgen concentrations in both the plasma and in the yolks of pre-ovulatory follicles were significantly elevated compared to controls. However, this measure of steroidogenic capacity did not explain variation in yolk testosterone levels, although physiological differences between house sparrows and more widely studied poultry models were revealed by this approach. Steroidogenic enzyme mRNA levels were detectable in all samples and were significantly lower in the most mature pre-ovulatory follicles. Of the four measured genes, CYP19A1 expression exhibited a significant negative relationship with yolk testosterone concentrations in laid eggs, revealing a key mechanism for between-female variation in yolk testosterone. Furthermore, this suggests that any factors which alter the expression of CYP19A1 within an individual female could have dramatic effects on offspring phenotype. PMID:23247271

  4. Corrosion Inhibition of a Green Scale Inhibitor Polyepoxysuccinic Acid

    Institute of Scientific and Technical Information of China (English)

    Rong Chun XIONG; Qing ZHOU; Gang WEI

    2003-01-01

    The corrosion inhibition of a green scale inhibitor, polyepoxysuccinic acid (PESA) wasstudied based on dynamic tests. It is found that when PESA is used alone, it had good corrosioninhibition. So, PESA should be included in the category of corrosion inhibitors. It is not only akind of green scale inhibitor, but also a green corrosion inhibitor. The synergistic effect betweenPESA and Zn2+ or sodium gluconate is poor. However, the synergistic effect among PESA, Zn2+and sodium gluconate is excellent, and the corrosion inhibition efficiency for carbon steel is higherthan 99%. Further study of corrosion inhibition mechanism reveals that corrosion inhibition ofPESA is not affected by carboxyl group, but by the oxygen atom inserted The existence ofoxygen atom in PESA molecular structure makes it easy to form stable chelate with pentacyclicstructure.

  5. The Aurora kinase inhibitors in cancer research and therapy.

    Science.gov (United States)

    Cicenas, Jonas

    2016-09-01

    Compounds that affect enzymatic function of kinases are valuable for the understanding of the complex biochemical processes in cells. Aurora kinases (AURKs) play a key role in the control of the mitosis. These kinases are frequently deregulated in different human cancers: overexpression, amplifications, translocations and deletions were reported in many cancer cell lines as well as patient tissues. These findings steered a rigorous hunt for small-molecule AURK inhibitors not only for research purposes as well as for therapeutic uses. In this review, we describe a number of AURK inhibitors and their use in cancer research and/or therapy. We hope to assist researchers and clinicians in deciding which inhibitor is most appropriate for their specific purpose. The review will also provide a broad overview of the clinical studies performed with some of these inhibitors (if such studies have been performed). PMID:26932147

  6. Inhibitors of lysosomal cysteine proteases

    OpenAIRE

    Lyanna O. L.; Chorna V. I.

    2011-01-01

    The review is devoted to the inhibitors of cysteine proteinases which are believed to be very important in many biochemical processes of living organisms. They participate in the development and progression of numerous diseases that involve abnormal protein turnover. One of the main regulators of these proteinases is their specific inhibitors: cystatins. The aim of this review was to present current knowledge about endogenous inhibitors of lysosomal cysteine proteases and their synthetic anal...

  7. Inhibitors of lysosomal cysteine proteases

    Directory of Open Access Journals (Sweden)

    Lyanna O. L.

    2011-04-01

    Full Text Available The review is devoted to the inhibitors of cysteine proteinases which are believed to be very important in many biochemical processes of living organisms. They participate in the development and progression of numerous diseases that involve abnormal protein turnover. One of the main regulators of these proteinases is their specific inhibitors: cystatins. The aim of this review was to present current knowledge about endogenous inhibitors of lysosomal cysteine proteases and their synthetic analogs.

  8. Molecular similarity of MDR inhibitors

    OpenAIRE

    Simon Gibbons; Mire Zloh

    2004-01-01

    Abstract: The molecular similarity of multidrug resistance (MDR) inhibitors was evaluated using the point centred atom charge approach in an attempt to find some common features of structurally unrelated inhibitors. A series of inhibitors of bacterial MDR were studied and there is a high similarity between these in terms of their shape, presence and orientation of aromatic ring moieties. A comparison of the lipophilic properties of these molecules has also been conducted suggesting that this ...

  9. ACE INHIBITORS: A COMPREHENSIVE REVIEW

    Directory of Open Access Journals (Sweden)

    Pradeep Kumar Arora* and Ashish Chauhan

    2013-02-01

    Full Text Available Hypertension is a chronic increase in blood pressure, characterized as primary and secondary hypertension. The disorder is associated with various risk factors like obesity, diabetes, age, lack of exercise etc. Hypertension is being treated since ancient times by Ayurvedic, Chinese and Unani medicine. Now various allopathic drugs are available which include diuretics, calcium channel blockers, α-blockers, β-blockers, vasodilators, central sympatholytics and ACE-inhibitors. Non-pharmacological treatments include weight reduction, dietary sodium reduction, increased potassium intake and reduction in alcohol consumption. ACE-inhibitors are widely used in the treatment of hypertension by inhibiting the angiotensin converting enzyme responsible for the conversion of angiotensin I to angiotensin II (responsible for vasoconstriction. Various structure activity relationship studies led to the synthesis of ACE-inhibitors, some are under clinical development. This comprehensive review gives various guidelines on classification of hypertension, hypertension therapy including ancient, pharmacological, non-pharmacological therapies, pharmacoeconomics, historical perspectives of ACE, renin, renin angiotensin system (circulating vs local RAS, mechanism of ACE inhibitors, and development of ACE inhibitors. Review also emphasizes on the recent advancements on ACE inhibitors including drugs in clinical trials, computational studies on ACE-inhibitors, peptidomimetics, dual, natural, multi-functional ACE inhibitors, and conformational requirements for ACE-inhibitors.

  10. Synthesis of Lysine Methyltransferase Inhibitors

    Science.gov (United States)

    Ye, Tao; Hui, Chunngai

    2015-07-01

    Lysine methyltransferase which catalyze methylation of histone and nonhistone proteins, play a crucial role in diverse biological processes and has emerged as a promising target for the development of various human diseases, including cancer, inflammation, and psychiatric disorders. However, inhibiting Lysine methyltransferases selectively has presented many challenges to medicinal chemists. During the past decade, lysine methyltransferase inhibitors covering many different structural classes have been designed and developed. In this review, we describe the development of selective, small-molecule inhibitors of lysine methyltransferases with an emphasis on their discovery and chemical synthesis. We highlight the current state of lysine methyltransferase inhibitors and discuss future directions and opportunities for lysine methyltransferase inhibitor discovery.

  11. CYP17 inhibitors for prostate cancer therapy.

    Science.gov (United States)

    Vasaitis, Tadas S; Bruno, Robert D; Njar, Vincent C O

    2011-05-01

    Prostate cancer (PC) is now the second most prevalent cause of death in men in the USA and Europe. At present, the major treatment options include surgical or medical castration. These strategies cause ablation of the production of testosterone (T), dihydrotestosterone (DHT) and related androgens by the testes. However, because these procedures do not affect adrenal, prostate and other tissues' androgen production, they are often combined with androgen receptor antagonists to block their action. Indeed, recent studies have unequivocally established that in castration-resistant prostate cancer (CRPC) many androgen-regulated genes become re-expressed and tissue androgen levels increase despite low serum levels. Clearly, inhibition of the key enzyme which catalyzes the biosynthesis of androgens from pregnane precursors, 17α-hydroxy/17,20-lyase (hereafter referred to as CYP17) could prevent androgen production from all sources. Thus, total ablation of androgen production by potent CYP17 inhibitors may provide effective treatment of prostate cancer patients. This review highlights the role of androgen biosynthesis in the progression of prostate cancer and the impact of CYP17 inhibitors, such as ketoconazole, abiraterone acetate, VN/124-1 (TOK-001) and TAK-700 in the clinic and in clinical development. Article from the special issue on Targeted Inhibitors. PMID:21092758

  12. Acetylcholinesterase Inhibitors: Pharmacology and Toxicology

    OpenAIRE

    Čolović, Mirjana B; Krstić, Danijela Z; Lazarević-Pašti, Tamara D; Bondžić, Aleksandra M; Vasić, Vesna M

    2013-01-01

    Acetylcholinesterase is involved in the termination of impulse transmission by rapid hydrolysis of the neurotransmitter acetylcholine in numerous cholinergic pathways in the central and peripheral nervous systems. The enzyme inactivation, induced by various inhibitors, leads to acetylcholine accumulation, hyperstimulation of nicotinic and muscarinic receptors, and disrupted neurotransmission. Hence, acetylcholinesterase inhibitors, interacting with the enzyme as their primary target, are appl...

  13. A NOVEL APPROACH TO REGULATE NITROGEN MINERALIZATION USING PROTEASE INHIBITORS

    Science.gov (United States)

    Mineralization of organic N sources by extracellular proteases affects both the availability of inorganic N to plants and losses of N to the environment. We hypothesized that (i) application of purified protease inhibitors would slow down soil N mineralization, and (ii) elevated concentrations of pr...

  14. Effects of the EGFR Inhibitor Erlotinib on Magnesium Handling

    DEFF Research Database (Denmark)

    Dimke, Henrik Anthony; van der Wijst, Jenny; Alexander, Todd R;

    2010-01-01

    A mutation in pro-EGF causes isolated hypomagnesemia, and monoclonal antibodies targeting the extracellular domain of the EGF receptor (EGFR) affect epithelial Mg(2+) transport. The effect of the EGFR tyrosine kinase inhibitor erlotinib on Mg(2+) homeostasis, however, remains unknown. Here, we in...

  15. Inhibition of matrix metalloproteinase-2 by PARP inhibitors

    International Nuclear Information System (INIS)

    Matrix metalloproteinase-2 (MMP-2), a ubiquitously expressed zinc-dependent endopeptidase, and poly(ADP-ribosyl) polymerase (PARP), a nuclear enzyme regulating DNA repair, are activated by nitroxidative stress associated with various pathologies. As MMP-2 plays a detrimental role in heart injuries resulting from enhanced nitroxidative stress, where PARP and MMP inhibitors are beneficial, we hypothesized that PARP inhibitors may affect MMP-2 activity. Using substrate degradation assays to determine MMP-2 activity we found that four PARP inhibitors (3-AB, PJ-34, 5-AIQ, and EB-47) inhibited 64 kDa MMP-2 in a concentration-dependent manner. The IC50 values of PJ-34 and 5-AIQ were in the high micromolar range and comparable to those of known MMP-2 inhibitors doxycycline, minocycline or o-phenanthroline, whereas those for 3-AB and EB-47 were in the millimolar range. Co-incubation of PARP inhibitors with doxycycline showed an additive inhibition of MMP-2 that was significant for 3-AB alone. These data demonstrate that the protective effects of some PARP inhibitors may include inhibition of MMP-2 activity.

  16. Inhibition of matrix metalloproteinase-2 by PARP inhibitors

    Science.gov (United States)

    Nicolescu, Adrian C.; Holt, Andrew; Kandasamy, Arulmozhi D.; Pacher, Pal; Schulz, Richard

    2009-01-01

    Matrix metalloproteinase-2 (MMP-2), a ubiquitously expressed zinc-dependent endopeptidase, and poly(ADP-ribosyl) polymerase (PARP), a nuclear enzyme regulating DNA repair, are activated by nitroxidative stress associated with various pathologies. As MMP-2 plays a detrimental role in heart injuries resulting from enhanced nitroxidative stress, where PARP and MMP inhibitors are beneficial, we hypothesized that PARP inhibitors may affect MMP-2 activity. Using substrate degradation assays to determine MMP-2 activity we found that four PARP inhibitors (3-AB, PJ-34, 5-AIQ, and EB-47) inhibited 64 kDa MMP-2 in a concentration-dependent manner. The IC50 values of PJ-34 and 5-AIQ were in the high micromolar range and comparable to those of known MMP-2 inhibitors doxycycline, minocycline or o-phenanthroline, whereas those for 3-AB and EB-47 were in the millimolar range. Co-incubation of PARP inhibitors with doxycycline showed an additive inhibition of MMP-2 that was significant for 3-AB alone. These data demonstrate that the protective effects of some PARP inhibitors may include inhibition of MMP-2 activity. PMID:19619515

  17. Inhibition of matrix metalloproteinase-2 by PARP inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Nicolescu, Adrian C.; Holt, Andrew; Kandasamy, Arulmozhi D. [Departments of Pharmacology and Pediatrics, Cardiovascular Research Centre, University of Alberta, Edmonton, Alta., Canada T6G 2S2 (Canada); Pacher, Pal [National Institutes of Health, NIAAA, Laboratory of Physiologic Studies, Bethesda, MD (United States); Schulz, Richard, E-mail: richard.schulz@ualberta.ca [Departments of Pharmacology and Pediatrics, Cardiovascular Research Centre, University of Alberta, Edmonton, Alta., Canada T6G 2S2 (Canada)

    2009-10-02

    Matrix metalloproteinase-2 (MMP-2), a ubiquitously expressed zinc-dependent endopeptidase, and poly(ADP-ribosyl) polymerase (PARP), a nuclear enzyme regulating DNA repair, are activated by nitroxidative stress associated with various pathologies. As MMP-2 plays a detrimental role in heart injuries resulting from enhanced nitroxidative stress, where PARP and MMP inhibitors are beneficial, we hypothesized that PARP inhibitors may affect MMP-2 activity. Using substrate degradation assays to determine MMP-2 activity we found that four PARP inhibitors (3-AB, PJ-34, 5-AIQ, and EB-47) inhibited 64 kDa MMP-2 in a concentration-dependent manner. The IC{sub 50} values of PJ-34 and 5-AIQ were in the high micromolar range and comparable to those of known MMP-2 inhibitors doxycycline, minocycline or o-phenanthroline, whereas those for 3-AB and EB-47 were in the millimolar range. Co-incubation of PARP inhibitors with doxycycline showed an additive inhibition of MMP-2 that was significant for 3-AB alone. These data demonstrate that the protective effects of some PARP inhibitors may include inhibition of MMP-2 activity.

  18. Optic nerve oxygen tension in pigs and the effect of carbonic anhydrase inhibitors

    DEFF Research Database (Denmark)

    Stefánsson, E; Jensen, P K; Eysteinsson, T;

    1999-01-01

    To evaluate how the oxygen tension of the optic nerve (ONP(O)2) is affected by the administration of the carbonic anhydrase inhibitors dorzolamide and acetazolamide and by alterations in oxygen and carbon dioxide in the breathing mixture.......To evaluate how the oxygen tension of the optic nerve (ONP(O)2) is affected by the administration of the carbonic anhydrase inhibitors dorzolamide and acetazolamide and by alterations in oxygen and carbon dioxide in the breathing mixture....

  19. Evaluation and Structural Basis for the Inhibition of Tankyrases by PARP Inhibitors.

    Science.gov (United States)

    Haikarainen, Teemu; Narwal, Mohit; Joensuu, Päivi; Lehtiö, Lari

    2014-01-01

    Tankyrases, an enzyme subfamily of human poly(ADP-ribosyl)polymerases, are potential drug targets especially against cancer. We have evaluated inhibition of tankyrases by known PARP inhibitors and report five cocrystal structures of the most potent compounds in complex with human tankyrase 2. The inhibitors include the small general PARP inhibitors Phenanthridinone, PJ-34, and TIQ-A as well as the more advanced inhibitors EB-47 and rucaparib. The compounds anchor to the nicotinamide subsite of tankyrase 2. Crystal structures reveal flexibility of the ligand binding site with implications for drug development against tankyrases and other ADP-ribosyltransferases. EB-47 mimics the substrate NAD(+) and extends from the nicotinamide to the adenosine subsite. The clinical ARTD1 inhibitor candidate rucaparib was the most potent tankyrase inhibitor identified (24 and 14 nM for tankyrases), which indicates that inhibition of tankyrases would affect the cellular responses of this compound. PMID:24900770

  20. Transcriptional Profiling of a Selective CREB Binding Protein Bromodomain Inhibitor Highlights Therapeutic Opportunities.

    Science.gov (United States)

    Chekler, Eugene L Piatnitski; Pellegrino, Jessica A; Lanz, Thomas A; Denny, R Aldrin; Flick, Andrew C; Coe, Jotham; Langille, Jonathan; Basak, Arindrajit; Liu, Shenping; Stock, Ingrid A; Sahasrabudhe, Parag; Bonin, Paul D; Lee, Kevin; Pletcher, Mathew T; Jones, Lyn H

    2015-12-17

    Bromodomains are involved in transcriptional regulation through the recognition of acetyl lysine modifications on diverse proteins. Selective pharmacological modulators of bromodomains are lacking, although the largely hydrophobic nature of the pocket makes these modules attractive targets for small-molecule inhibitors. This work describes the structure-based design of a highly selective inhibitor of the CREB binding protein (CBP) bromodomain and its use in cell-based transcriptional profiling experiments. The inhibitor downregulated a number of inflammatory genes in macrophages that were not affected by a selective BET bromodomain inhibitor. In addition, the CBP bromodomain inhibitor modulated the mRNA level of the regulator of G-protein signaling 4 (RGS4) gene in neurons, suggesting a potential therapeutic opportunity for CBP inhibitors in the treatment of neurological disorders. PMID:26670081

  1. [Pharmacology of bone resorption inhibitor].

    Science.gov (United States)

    Menuki, Kunitaka; Sakai, Akinori

    2015-10-01

    Currently, bone resorption inhibitor is mainly used for osteoporosis. A number of these agents have been developed. These pharmacological action are various. Bisphosphonate inhibit functions of the osteoclasts by inducing apoptosis. On the one hand, RANK-ligand inhibitor and selective estrogen receptor modulator inhibit formation of osteoclasts. It is important to understand these pharmacological action for the selection of the appropriate medicine. PMID:26529923

  2. Nutritional significance of lectins and enzyme inhibitors from legumes.

    Science.gov (United States)

    Lajolo, Franco M; Genovese, Maria Inés

    2002-10-23

    Legumes have natural components, such as lectins, amylase, and trypsin inhibitors, that may adversely affect their nutritional properties. Much information has already been obtained on their antinutritional significance and how to inactivate them by proper processing. Chronic ingestion of residual levels is unlikely to pose risks to human health. On the other hand, the ability of these molecules to inhibit some enzymes such as trypsin, chymotrypsin, disaccharidases, and alpha-amylases, to selectively bind to glycoconjugates, and to enter the circulatory system may be a useful tool in nutrition and pharmacology. Trypsin inhibitors have also been studied as cancer risk reducing factors. These components seem to act as plant defense substances. However, increased contents may represent an impairment of the nutritional quality of legumes because these glycoproteins and the sulfur-rich protease inhibitors have been shown to be poorly digested and to participate in chemical reactions during processing reducing protein digestibility, a still unsolved question. PMID:12381157

  3. BRD4 Inhibitor Inhibits Colorectal Cancer Growth and Metastasis

    Directory of Open Access Journals (Sweden)

    Yuan Hu

    2015-01-01

    Full Text Available Post-translational modifications have been identified to be of great importance in cancers and lysine acetylation, which can attract the multifunctional transcription factor BRD4, has been identified as a potential therapeutic target. In this paper, we identify that BRD4 has an important role in colorectal cancer; and that its inhibition substantially wipes out tumor cells. Treatment with inhibitor MS417 potently affects cancer cells, although such effects were not always outright necrosis or apoptosis. We report that BRD4 inhibition also limits distal metastasis by regulating several key proteins in the progression of epithelial-to-mesenchymal transition (EMT. This effect of BRD4 inhibitor is demonstrated via liver metastasis in animal model as well as migration and invasion experiments in vitro. Together, our results demonstrate a new application of BRD4 inhibitor that may be of clinical use by virtue of its ability to limit metastasis while also being tumorcidal.

  4. Experiencing affective interactive art

    NARCIS (Netherlands)

    Bialoskorski, Leticia S.S.; Westerink, Joyce H.D.M.; Broek, van den Egon L.

    2010-01-01

    The progress in the field of affective computing enables the realization of affective art. This paper describes the affective interactive art system Mood Swings, which interprets and visualizes affect expressed by a person. Mood Swings is founded on the integration of a framework for affective move

  5. An overview on 5alpha-reductase inhibitors.

    Science.gov (United States)

    Aggarwal, Saurabh; Thareja, Suresh; Verma, Abhilasha; Bhardwaj, Tilak Raj; Kumar, Manoj

    2010-02-01

    Benign prostatic hyperplasia (BPH) is the noncancerous proliferation of the prostate gland associated with benign prostatic obstruction and lower urinary tract symptoms (LUTS) such as frequency, hesitancy, urgency, etc. Its prevalence increases with age affecting around 70% by the age of 70 years. High activity of 5alpha-reductase enzyme in humans results in excessive dihydrotestosterone levels in peripheral tissues and hence suppression of androgen action by 5alpha-reductase inhibitors is a logical treatment for BPH as they inhibit the conversion of testosterone to dihydrotestosterone. Finasteride (13) was the first steroidal 5alpha-reductase inhibitor approved by U.S. Food and Drug Administration (USFDA). In human it decreases the prostatic DHT level by 70-90% and reduces the prostatic size. Dutasteride (27) another related analogue has been approved in 2002. Unlike Finasteride, Dutasteride is a competitive inhibitor of both 5alpha-reductase type I and type II isozymes, reduced DHT levels >90% following 1 year of oral administration. A number of classes of non-steroidal inhibitors of 5alpha-reductase have also been synthesized generally by removing one or more rings from the azasteroidal structure or by an early non-steroidal lead (ONO-3805) (261). In this review all categories of inhibitors of 5alpha-reductase have been covered. PMID:19879888

  6. Microbial inhibitors of cysteine proteases.

    Science.gov (United States)

    Kędzior, Mateusz; Seredyński, Rafał; Gutowicz, Jan

    2016-08-01

    Cysteine proteases are one of the major classes of proteolytic enzymes involved in a number of physiological and pathological processes in plants, animals and microorganisms. When their synthesis, activity and localization in mammalian cells are altered, they may contribute to the development of many diseases, including rheumatoid arthritis, osteoporosis and cancer. Therefore, cysteine proteases have become promising drug targets for the medical treatment of these disorders. Inhibitors of cysteine proteases are also produced by almost every group of living organisms, being responsible for the control of intracellular proteolytic activity. Microorganisms synthesize cysteine protease inhibitors not only to regulate the activity of endogenous, often virulent enzymes, but also to hinder the host's proteolytic defense system and evade its immune responses against infections. Present work describes known to date microbial inhibitors of cysteine proteases in terms of their structure, enzyme binding mechanism, specificity and pathophysiological roles. The overview of both proteinaceous and small-molecule inhibitors produced by all groups of microorganisms (bacteria, archaea, fungi, protists) and viruses is provided. Subsequently, possible applications of microbial inhibitors in science, medicine and biotechnology are also highlighted. PMID:27048482

  7. Effects of auxin transport inhibitors on gibberellins in pea

    International Nuclear Information System (INIS)

    The effects of the auxin transport inhibitors 2,3,5-triiodobenzoic acid (TIBA), 9-hydroxyfluorene-9-carboxylic acid (HFCA), and 1-N-naphthylphthalamic acid (NPA) on gibberellins (GAs) in the garden pea (Pisum sativum L.) were studied. Application of these compounds to elongating internodes of intact wild type plants reduced markedly the endogenous level of the bioactive gibberellin A1. (GA1) below the application site. Indole-3-acetic acid (IAA) levels were also reduced, as was internode elongation. The auxin transport inhibitors did not affect the level of endogenous GA1 above the application site markedly, nor that of GA1 precursors above or below it. When plants were treated with [13C,3H]GA20, TIBA reduced dramatically the level of [13C,3H]GA1 recovered below the TIBA application site. The internodes treated with auxin transport inhibitors appeared to be still in the phase where endogenous GA1 affects elongation, as indicated by the strong response to applied GA1 by internodes of a GA1-deficient line at the same stage of expansion. On the basis of the present results it is suggested that caution be exercised when attributing the developmental effects of auxin transport inhibitors to changes in IAA level alone

  8. Identification of pyrazolopyridazinones as PDEδ inhibitors.

    Science.gov (United States)

    Papke, Björn; Murarka, Sandip; Vogel, Holger A; Martín-Gago, Pablo; Kovacevic, Marija; Truxius, Dina C; Fansa, Eyad K; Ismail, Shehab; Zimmermann, Gunther; Heinelt, Kaatje; Schultz-Fademrecht, Carsten; Al Saabi, Alaa; Baumann, Matthias; Nussbaumer, Peter; Wittinghofer, Alfred; Waldmann, Herbert; Bastiaens, Philippe I H

    2016-01-01

    The prenyl-binding protein PDEδ is crucial for the plasma membrane localization of prenylated Ras. Recently, we have reported that the small-molecule Deltarasin binds to the prenyl-binding pocket of PDEδ, and impairs Ras enrichment at the plasma membrane, thereby affecting the proliferation of KRas-dependent human pancreatic ductal adenocarcinoma cell lines. Here, using structure-based compound design, we have now identified pyrazolopyridazinones as a novel, unrelated chemotype that binds to the prenyl-binding pocket of PDEδ with high affinity, thereby displacing prenylated Ras proteins in cells. Our results show that the new PDEδ inhibitor, named Deltazinone 1, is highly selective, exhibits less unspecific cytotoxicity than the previously reported Deltarasin and demonstrates a high correlation with the phenotypic effect of PDEδ knockdown in a set of human pancreatic cancer cell lines. PMID:27094677

  9. Electrochemical studies of corrosion inhibitors

    Science.gov (United States)

    Danford, M. D.

    1990-01-01

    The effect of single salts, as well as multicomponent mixtures, on corrosion inhibition was studied for type 1010 steel; for 5052, 1100, and 2219-T87 aluminum alloys; and for copper. Molybdate-containing inhibitors exhibit an immediate, positive effect for steel corrosion, but an incubation period may be required for aluminum before the effect of a given inhibitor can be determined. The absence of oxygen was found to provide a positive effect (smaller corrosion rate) for steel and copper, but a negative effect for aluminum. This is attributed to the two possible mechanisms by which aluminum can oxidize. Corrosion inhibition is generally similar for oxygen-rich and oxygen-free environments. The results show that the electrochemical method is an effective means of screening inhibitors for the corrosion of single metals, with caution to be exercised in the case of aluminum.

  10. Corrosion inhibitors from expired drugs.

    Science.gov (United States)

    Vaszilcsin, Nicolae; Ordodi, Valentin; Borza, Alexandra

    2012-07-15

    This paper presents a method of expired or unused drugs valorization as corrosion inhibitors for metals in various media. Cyclic voltammograms were drawn on platinum in order to assess the stability of pharmaceutically active substances from drugs at the metal-corrosive environment interface. Tafel slope method was used to determine corrosion rates of steel in the absence and presence of inhibitors. Expired Carbamazepine and Paracetamol tablets were used to obtain corrosion inhibitors. For the former, the corrosion inhibition of carbon steel in 0.1 mol L(-1) sulfuric acid solution was about 90%, whereas for the latter, the corrosion inhibition efficiency of the same material in the 0.25 mol L(-1) acetic acid-0.25 mol L(-1) sodium acetate buffer solution was about 85%. PMID:22561212

  11. Positron emitter labeled enzyme inhibitors

    International Nuclear Information System (INIS)

    This invention involves a new strategy for imagining and mapping enzyme activity in the living human and animal body using positron emitter-labeled suicide enzyme inactivators or inhibitors which become covalently bound to the enzyme as a result of enzymatic catalysis. Two such suicide inactivators for monoamine oxidase have been labeled with carbon-11 and used to map the enzyme subtypes in the living human and animal body using PET. By using positron emission tomography to image the distribution of radioactivity produced by the body penetrating radiation emitted by carbon-11, a map of functionally active monoamine oxidase activity is obtained. Clorgyline and L-deprenyl are suicide enzyme inhibitors and irreversibly inhibit monoamine oxidase. When these inhibitors are labeled with carbon-11 they provide selective probes for monoamine oxidase localization and reactivity in vivo using positron emission tomography

  12. Modulation of human basophil histamine release by protein kinase C inhibitors differs with secretagogue and with inhibitor.

    Science.gov (United States)

    Bergstrand, H; Lundquist, B; Karabelas, K; Michelsen, P

    1992-03-01

    To assess possible involvement of protein kinase C (PKC) in human basophil degranulation, the present work compared effects of various purported PKC inhibitors on leukocyte histamine release triggered by different stimuli. The effects recorded varied with the inhibitor and the secretagogue used; moreover, with a given secretagogue, different inhibitors often displayed different activities. Thus, histamine release triggered by the PKC activator 4 beta-phorbol 12-myristate 13-acetate was blocked by K252a, staurosporine and the purported specific PKC inhibitor Ro 31-7549, and reduced by calphostin C, H-7, TMB-8 and W-7 but not affected by polymyxin B; it was augmented by 2.1 microM palmitoyl carnitine. The leukocyte response induced by another putative activator of PKC, 1,2-isopropylidene-3-decanoyl-sn-glycerol, was also enhanced by 2.1 microM palmitoyl carnitine, slightly increased by staurosporine, TMB-8 and W-7 but not affected by calphostin C, H-7, K252a or Ro 31-7549, whereas the hyperosmolar mannitol-induced response was reduced by H-7, calphostin C, TMB-8 and W-7 and slightly augmented by staurosporine. Anti-IgE-induced histamine release was blocked by staurosporine and K252a and reduced by calphostin C, sphingosine, TMB-8 and W-7 but not affected by H-7, polymyxin B or retinal. It was enhanced by Ro 31-7549. In contrast, leukocyte histamine release induced by calcium ionophore A23187 or by ionomycin was blocked by retinal, TMB-8 and W-7 and reduced by calphostin C and palmitoyl carnitine but enhanced by H-7, staurosporine and polymyxin B; K252a and Ro 31-7549 did not affect such responses. Formyl-methionyl-leucyl-phenylalanine-triggered histamine release was barely affected by any agent used. Thus, the specific PKC inhibitor Ro 31-7549 selectively blocked 4 beta-phorbol 12-myristate 13-acetate-triggered leukocyte histamine release. These results imply that examined secretagogues trigger human leukocyte histamine release through partly separate pathways

  13. Effect of inhibitors of prostaglandin synthesis on hepatic drug clearance.

    OpenAIRE

    Feely, J; Wood, A. J.

    1983-01-01

    The effect of inhibition of prostaglandin synthesis on the systemic clearance of indocyanine green and antipyrine was studied in seven subjects. Antipyrine clearance was not altered by indomethacin suggesting that oxidative metabolism was not affected. Both aspirin and indomethacin decreased the clearance of indocyanine green presumably by reducing liver blood flow. These results suggest that an effect of inhibitors of prostaglandin synthesis on hepatic drug clearance is likely to be confined...

  14. Topical Calcineurin Inhibitors for Atopic Dermatitis: Review and Treatment Recommendations

    OpenAIRE

    Carr, Warner W

    2013-01-01

    Atopic dermatitis (AD) is an inflammatory skin disease commonly affecting children and managed by pediatricians, primary care physicians, allergists, and dermatologists alike. For many years, the only available topical pharmacological treatment was topical corticosteroids. This changed in 2000–2001, when topical formulations of two calcineurin inhibitors (tacrolimus and pimecrolimus) were approved for short-term or chronic intermittent treatment of AD in patients ≥2 years of age, in whom othe...

  15. Pseudobulbar affect: prevalence and management

    Directory of Open Access Journals (Sweden)

    Ahmed A

    2013-11-01

    Full Text Available Aiesha Ahmed, Zachary SimmonsDepartment of Neurology, Penn State Hershey Medical Center, Hershey, PA, USAAbstract: Pseudobulbar affect (PBA may occur in association with a variety of neurological diseases, and so may be encountered in the setting of amyotrophic lateral sclerosis, extrapyramidal and cerebellar disorders, multiple sclerosis, traumatic brain injury, Alzheimer's disease, stroke, and brain tumors. The psychological consequences and the impact on social interactions may be substantial. Although it is most commonly misidentified as a mood disorder, particularly depression or a bipolar disorder, there are characteristic features that can be recognized clinically or assessed by validated scales, resulting in accurate identification of PBA, and thus permitting proper management and treatment. Mechanistically, PBA is a disinhibition syndrome in which pathways involving serotonin and glutamate are disrupted. This knowledge has permitted effective treatment for many years with antidepressants, particularly tricyclic antidepressants and selective serotonin reuptake inhibitors. A recent therapeutic breakthrough occurred with the approval by the Food and Drug Administration of a dextromethorphan/quinidine combination as being safe and effective for treatment of PBA. Side effect profiles and contraindications differ for the various treatment options, and the clinician must be familiar with these when choosing the best therapy for an individual, particularly elderly patients and those with multiple comorbidities and concomitant medications.Keywords: pseudobulbar affect, emotional lability, depression, amyotrophic lateral sclerosis, multiple sclerosis

  16. An electrochemical and microstructural characterization of steel-mortar admixed with corrosion inhibitors

    Institute of Scientific and Technical Information of China (English)

    Tuan; Anh; Nguyen; Recep; AVCI

    2009-01-01

    The present research brings new insights on the role of admixed corrosion inhibitors in the processes of cement hydration and rebar corrosion. The admixing of NaCl and the corrosion inhibitors in fresh mortar was found to alter the morphology and microstructure of the hardened mortar at the steel-mortar interfacial region. The admixing of the inhibitors increased the risk of carbonation of cement hydrates at the steel-mortar interfacial region, but partially displaced chloride ions. Chloride and the admixed inhibitors facilitated the formation of different cement hydrates and affected chloride binding at the steel-mortar interfacial region. The admixing of all three inhibitors was found to increase the polarization resistance of steel, indicating reduced corrosion rate of the steel over 48-day exposures to salt ponding.

  17. Incorporating vapor corrosion inhibitors (VCIs) in oil and gas pipeline additive formulations

    Energy Technology Data Exchange (ETDEWEB)

    Kharshan, M.; Furman, A. [Cortec Corp., St. Paul, MN (United States)

    1998-12-31

    Two new oil and gas pipeline additives were formulated utilizing volatile corrosion inhibitors (VCIS). These products provide a very high level of protection for steel subjected to different types of corrosive petrochemicals due to surface adsorption and vapor phase action environments. The formulation work was based on fatty acid imidazoline chemistry combined with different organic acids. Different surfactants were used to provide maximum wetting properties to the inhibitor and faster transport of inhibitor from the oil or gas phase to the water. Vapor corrosion inhibitors were introduced in the formulation. A Windows-compatible software was used to identify the vital factors that affect the quality of the product. The protective properties of newly developed inhibitors were evaluated in various types of corrosive mediums.

  18. Less-toxic corrosion inhibitors

    Science.gov (United States)

    Humphries, T. S.

    1981-01-01

    Combinations of borates, nitrates, phosphates, silicates, and sodium MBT protect aluminum from corrosion in fresh water. Most effective combinations contained sodium phosphate and were alkaline. These inhibitors replace toxic chromates which are subject to governmental restrictions, but must be used in larger quantities. Experimental exposure times varied from 1 to 14 months depending upon nature of submersion solution.

  19. Proton pump inhibitors and osteoporosis

    DEFF Research Database (Denmark)

    Andersen, Bjarne Nesgaard; Johansen, Per Birger; Abrahamsen, Bo

    2016-01-01

    PURPOSE OF REVIEW: The purpose of the review is to provide an update on recent advances in the evidence based on proton pump inhibitors (PPI) as a possible cause of osteoporosis and osteoporotic fractures. This review focuses, in particular, on new studies published in the last 18 months and a...

  20. PDE-5 inhibitors: clinical points.

    Science.gov (United States)

    Doumas, Michael; Lazaridis, Antonios; Katsiki, Niki; Athyros, Vasilios

    2015-01-01

    Erectile dysfunction is usually of vascular origin and is frequently encountered in men with cardiovascular disease. The introduction of phosphodiesterase-5 inhibitors has revolutionized the management of patients with erectile dysfunction. Currently available phosphodiesterase-5 inhibitors have distinct pharmacokinetic and pharmacodynamic properties, thus permitting for tailoring sexual therapy according to patient characteristics and needs. Phosphodiesterase-5 inhibitors possess vasorelaxing properties and exert systemic hemodynamic effects, which need to be taken into account when other cardiovascular drugs are co-administered. Special caution is needed with alpha-blockers, while the co-administration with nitrates is contra-indicated due to the risk of life-threatening hypotension. This review presents the advent of sexual therapy, describes the mechanism of action and the specific characteristics of commercially available phosphodiesterase-5 inhibitors, summarizes the efficacy and safety of these drugs with special emphasis on the cardiovascular system, and discusses the clinical criteria used for the selection of each drug for the individual patient. PMID:25392015

  1. Retroviral proteinases and their inhibitors

    Czech Academy of Sciences Publication Activity Database

    Sedláček, Juraj

    2000-01-01

    Roč. 3, 3,4 (2000), s. 23-24. [Proteolytic enzymes and their inhibitors in physiology and pathogenesis.. 14.09.2000, Plzen] Institutional research plan: CEZ:AV0Z5052915 Subject RIV: EB - Genetics ; Molecular Biology

  2. Corrosion Inhibitors for Reinforced Concrete

    OpenAIRE

    ECT Team, Purdue

    2007-01-01

    Steel corrosion in reinforced concrete structures has been a major problem across the U.S. Steel-reinforced concrete structures are continually subject to attack by corrosion brought on by naturally occurring environmental conditions. FerroGard, a corrosion inhibitor, developed by Sika Corporation, penetrates hardened concrete to dramatically reduce corrosion by 65% and extend the structure's service life.

  3. Biocatalysts with enhanced inhibitor tolerance

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Shihui; Linger, Jeffrey; Franden, Mary Ann; Pienkos, Philip T.; Zhang, Min

    2015-12-08

    Disclosed herein are biocatalysts for the production of biofuels, including microorganisms that contain genetic modifications conferring tolerance to growth and fermentation inhibitors found in many cellulosic feedstocks. Methods of converting cellulose-containing materials to fuels and chemicals, as well as methods of fermenting sugars to fuels and chemicals, using these biocatalysts are also disclosed.

  4. Proton pump inhibitors and gastroenteritis

    NARCIS (Netherlands)

    R.J. Hassing (Robert); A. Verbon (Annelies); H. de Visser (Herman); A. Hofman (Albert); B.H.Ch. Stricker (Bruno)

    2016-01-01

    textabstractAn association between proton pump inhibitor (PPI) therapy and bacterial gastroenteritis has been suggested as well as contradicted. The aim of this study was to examine the association between the use of PPIs and occurrence of bacterial gastroenteritis in the prospective Rotterdam Study

  5. Radiosensitizing Effect of TRPV1 Channel Inhibitors in Cancer Cells.

    Science.gov (United States)

    Nishino, Keisuke; Tanamachi, Keisuke; Nakanishi, Yuto; Ide, Shunta; Kojima, Shuji; Tanuma, Sei-Ichi; Tsukimoto, Mitsutoshi

    2016-07-01

    Radiosensitizers are used in cancer therapy to increase the γ-irradiation susceptibility of cancer cells, including radioresistant hypoxic cancer cells within solid tumors, so that radiotherapy can be applied at doses sufficiently low to minimize damage to adjacent normal tissues. Radiation-induced DNA damage is repaired by multiple repair systems, and therefore these systems are potential targets for radiosensitizers. We recently reported that the transient receptor potential vanilloid type 1 (TRPV1) channel is involved in early responses to DNA damage after γ-irradiation of human lung adenocarcinoma A549 cells. Therefore, we hypothesized that TRPV1 channel inhibitors would have a radiosensitizing effect by blocking repair of radiation-induced cell damage. Here, we show that pretreatment of A549 cells with the TRPV1 channel inhibitors capsazepine, AMG9810, SB366791 and BCTC suppressed the γ-ray-induced activation of early DNA damage responses, i.e., activation of the protein kinase ataxia-telangiectasia mutated (ATM) and accumulation of p53-binding protein 1 (53BP1). Further, the decrease of survival fraction at one week after γ-irradiation (2.0 Gy) was enhanced by pretreatment of cells with these inhibitors. On the other hand, inhibitor pretreatment did not affect cell viability, the number of apoptotic or necrotic cells, or DNA synthesis at 24 h after irradiation. These results suggest that inhibition of DNA repair by TRPV1 channel inhibitors in irradiated A549 cells caused gradual loss of proliferative ability, rather than acute facilitation of apoptosis or necrosis. TRPV1 channel inhibitors could be novel candidates for radiosensitizers to improve the efficacy of radiation therapy, either alone or in combination with other types of radiosensitizers. PMID:27150432

  6. Comparison of the effects of the PI3K/mTOR inhibitors NVP-BEZ235 and GSK2126458 on tamoxifen-resistant breast cancer cells

    Science.gov (United States)

    Kim, Ji Eun; Rewcastle, Gordon W; Finlay, Graeme J; Baguley, Bruce C

    2011-01-01

    Background Treatment with anti-estrogens or aromatase inhibitors is commonly used for patients with estrogen receptor-positive (ER+) breast cancers; however resistant disease develops almost inevitably, requiring a choice of secondary therapy. One possibility is to use inhibitors of the PI3K/mTOR pathway and several candidate drugs are in development. We examined the in vitro effects of two inhibitors of the PI3K/mTOR pathway on resistant MCF-7 cells. Results The derived sub-lines showed increased resistance to tamoxifen but none exhibited concomitantly increased sensitivity to the PI3K inhibitors. NVP-BEZ235 and GSK2126458 acted mainly by induction of cell cycle arrest, particularly in G1-phase, rather than by induction of apoptosis. The lines varied considerably in their utilization of the AKT, p70S6K and ERK pathways. NVP-BEZ235 and GSK2126458 inhibited AKT signaling but NVP-BEZ235 showed greater effects than GSK2126458 on p70S6K and rpS6 signaling with effects resembling those of rapamycin. Methods We cultured MCF-7 cells for prolonged periods either in the presence of the anti-estrogen tamoxifen (three sub-lines) or in estrogen free medium (two sub-lines) to mimic the effects of clinical treatment. We then analyzed the effects of two dual PI3K/mTOR phosphoinositide-3-kinase inhibitors, NVP-BEZ235 and GSK2126458, on the growth and signaling pathways of these MCF-7 sub-lines. The functional status of the PI3K, mTOR and ERK pathways was analyzed by measuring phosphorylation of AKT, p70S6K, rpS6 and ERK. Conclusion Increased resistance to tamoxifen in these MCF-7 sub-lines is not associated with hypersensitivity to PI3K inhibitors. While both drugs inhibited AKT signaling, NVP-BEZ235 resembled rapamycin in inhibiting the mTOR pathway. PMID:21464613

  7. Lipoxygenase inhibitor peptides and their use

    OpenAIRE

    Schurink, M.; Boeriu, C.G.; Berkel, van, A.M.; Wichers, H.J.

    2006-01-01

    The present invention is in the field of enzyme inhibition. In particular it relates to peptide inhibitors for lipoxygenases. The lipoxygenase peptide inhibitors of have the potential to be used as therapeutic drugs as well as food preservatives.

  8. How inhibiting nitrification affects nitrogen cycle and reduces environmental impacts of anthropogenic nitrogen input

    Science.gov (United States)

    We conducted a meta-analysis of 103 nitrification inhibitor (NI) studies, and evaluated how NI application affects crop productivity and other ecosystem services in agricultural systems. Our results showed that, compared to conventional fertilizer practice, applications of NI alo...

  9. The chloride channel inhibitor NS3736 [corrected] prevents bone resorption in ovariectomized rats without changing bone formation

    DEFF Research Database (Denmark)

    Schaller, Sophie; Henriksen, Kim; Sveigaard, Christina;

    2004-01-01

    Chloride channel activity is essential for osteoclast function. Consequently, inhibition of the osteoclastic chloride channel should prevent bone resorption. Accordingly, we tested a chloride channel inhibitor on bone turnover and found that it inhibits bone resorption without affecting bone form...

  10. Inhibitors of glycoprotein processing alter T-cell proliferative responses to antigen and to interleukin 2.

    OpenAIRE

    Wall, K A; Pierce, J D; Elbein, A D

    1988-01-01

    Most of the cell-surface molecules involved in T-cell immune responses are N-linked glycoproteins. We have investigated the effects of inhibitors of glycoprotein processing on specific T-cell functions, with the dual aims of examining the functional role of carbohydrate and of testing the usefulness of such compounds as immunomodulators. Treatment of a cloned murine helper T-cell line with these inhibitors differentially affects the proliferative response of the cell, depending upon the natur...

  11. Facilitators and inhibitors of health-promoting behaviors: The experience of Iranian women of reproductive age

    Directory of Open Access Journals (Sweden)

    Azam Baheiraei

    2013-01-01

    Conclusions: In these women′s experience, factors influencing health-promoting behaviors were either facilitators or inhibitors; most were inhibitors. The findings of this study show that, in addition to personal factors, the pursuit of health-promoting behaviors is affected by socio-environmental factors. These results will be useful in designing interventions and plans for women′s health promotion that focus on the improvement of their environment and the modification of social factors.

  12. The fatty acid synthase inhibitor triclosan: repurposing an anti-microbial agent for targeting prostate cancer

    OpenAIRE

    Sadowski, Martin C.; Pouwer, Rebecca H.; Jennifer H. Gunter; Lubik, Amy A.; Quinn, Ronald J.; Nelson, Colleen C.

    2014-01-01

    Inhibition of FASN has emerged as a promising therapeutic target in cancer, and numerous inhibitors have been investigated. However, severe pharmacological limitations have challenged their clinical testing. The synthetic FASN inhibitor triclosan, which was initially developed as a topical antibacterial agent, is merely affected by these pharmacological limitations. Yet, little is known about its mechanism in inhibiting the growth of cancer cells. Here we compared the cellular and molecular e...

  13. Modulation of C1-Inhibitor and Plasma Kallikrein Activities by Type IV Collagen

    OpenAIRE

    Sriram Ravindran; Marc Schapira; Patston, Philip A.

    2012-01-01

    The contact system of coagulation can be activated when in contact with biomaterials. As collagen is being tested in novel biomaterials in this study, we have investigated how type IV collagen affects plasma kallikrein and C1-inhibitor. Firstly, we showed C1-inhibitor binds to type IV collagen with a Kd of 0.86 μM. The effects of type IV collagen on plasma kallikrein, factor XIIa, and β-factor XIIa activity and on C1-inhibitor function were determined. Factor XIIa rapidly lost activity in the...

  14. Isolation and characterization of a novel endogenous inhibitor of the proteasome

    Energy Technology Data Exchange (ETDEWEB)

    Xiaochong Li (New York Medical Coll., Valhalla (United States) State Univ. of New York, Brooklyn (United States)); Gu, M.; Etlinger, J.D. (New York Medical Coll., Valhalla (United States))

    1991-10-08

    A novel endogenous inhibitor of the proteasome (high molecular weight multicatalytic protease) has been isolated and characterized from human erythrocytes. After purification by ion-exchange and sizing chromatography, the inhibitor displayed a native molecular mass of approximately 200 kDa and contained a single subunit of 50 kDa with an isoelectric point of 6.9. Although the inhibitor noncompetitively blocks proteolysis of (methyl-{sup 14}C)-{alpha}-casein and inhibits hydrolysis of Suc-Leu-Leu-Val-Tyr-AMC, it did not affect hydrolysis of other peptide substrates, such as MeOSuc-Phe-Leu-Phe-MNA and Z-Ala-Arg-Arg-MNA. To further characterize the 50-kDa inhibitor, a monoclonal antibody (MI-8) was generated that showed specific binding upon Western blot analysis of both native PAGE and SDS-PAGE. Immunoprecipitation with MI-8 specifically removed inhibitor activity against the proteasome. The 50-kDa inhibitor is distinct from a previously described 40-kDa inhibitor of the proteasome on the basis of lack of cross-reactivity with MI-8 and dissimilar peptide digest patterns. It is suggested that these endogenous inhibitors may have a role in ATP/ubiquitin-dependent proteolysis and/or other cellular functions involving this protease.

  15. Mechanisms Regulating Resistance to Inhibitors of Topoisomerase II

    Directory of Open Access Journals (Sweden)

    Ram eGanapathi

    2013-08-01

    Full Text Available Inhibitors of topoisomerase II are clinically effective in the management of hematological malignancies and solid tumors. The efficacy of anti-tumor drugs targeting topoisomerase II is often limited by resistance and studies with in vitro cell culture models have provided several insights on potential mechanisms. Multidrug-transporters that are involved in the efflux and consequently reduced cytotoxicity of diverse anti-tumor agents suggest that they play an important role in resistance to clinically active drugs. However in clinical trials, modulating the multidrug resistant phenotype with agents that inhibit the efflux pump has not had an impact. Since reduced drug accumulation per se is insufficient to explain tumor cell resistance to topoisomerase II inhibitors several studies have focused on characterizing mechanisms that impact on DNA damage mediated by drugs that target the enzyme. Mammalian topoisomerase IIα and topoisomerase IIβ isozymes exhibit similar catalytic, but different biologic, activities. Whereas topoisomerase IIα is associated with cell division, topoisomerase IIβ is involved in differentiation. In addition to site specific mutations that can affect drug induced topoisomerase II-mediated DNA damage, post-translation modification of topoisomerase II primarily by phosphorylation can potentially affect enzyme-mediated DNA damage and the downstream cytotoxic response of drugs targeting topoisomerase II. Signaling pathways that can affect phosphorylation and changes in intracellular calcium levels/calcium dependent signaling that can regulate site-specific phosphorylation of topoisomerase have an impact on downstream cytotoxic effects of topoisomerase II inhibitors. Overall, tumor cell resistance to inhibitors of topoisomerase II is a complex process that is orchestrated not only by cellular pharmacokinetics but more importantly by enzymatic alterations that govern the intrinsic drug sensitivity.

  16. New horizons for cholesterol ester transfer protein inhibitors.

    Science.gov (United States)

    Schwartz, Gregory G

    2012-02-01

    High-density lipoprotein (HDL) cholesterol levels bear an inverse relationship to cardiovascular risk. To date, however, no intervention specifically targeting HDL has been demonstrated to reduce cardiovascular risk. Cholesterol ester transfer protein (CETP) mediates transfer of cholesterol ester from HDL to apolipoprotein B-containing particles. Most, but not all observational cohort studies indicate that genetic polymorphisms of CETP associated with reduced activity and higher HDL cholesterol levels are also associated with reduced cardiovascular risk. Some, but not all studies indicate that CETP inhibition in rabbits retards atherosclerosis, whereas transgenic CETP expression in mice promotes atherosclerosis. Torcetrapib, the first CETP inhibitor to reach phase III clinical development, was abandoned due to excess mortality associated with increases in aldosterone and blood pressure. Two other CETP inhibitors have entered phase III clinical development. Anacetrapib is a potent inhibitor of CETP that produces very large increases in HDL cholesterol and large reductions in low-density lipoprotein (LDL) cholesterol, beyond those achieved with statins. Dalcetrapib is a less potent CETP inhibitor that produces smaller increases in HDL cholesterol with minimal effect on LDL cholesterol. Both agents appear to allow efflux of cholesterol from macrophages to HDL in vitro, and neither agent affects blood pressure or aldosterone in vivo. Two large cardiovascular outcomes trials, one with anacetrapib and one with dalcetrapib, should provide a conclusive test of the hypothesis that inhibition of CETP decreases cardiovascular risk. PMID:22083134

  17. Glaucoma and the applications of carbonic anhydrase inhibitors.

    Science.gov (United States)

    Scozzafava, Andrea; Supuran, Claudiu T

    2014-01-01

    Inhibition of carbonic anhydrase (CA, EC 4.2.1.1) has pharmacologic applications in the treatment of glaucoma, a disease affecting a large number of people and characterized by an elevated intraocular pressure (IOP). At least three isoforms, CA II, IV and XII are targeted by the sulfonamide inhibitors, some of which are clinically used drugs. Acetazolamide, methazolamide and dichlorophenamide are first generation CA inhibitors (CAIs) still used as systemic drugs for the management of this disease. Dorzolamide and brinzolamide represent the second generation inhibitors, being used topically, as eye drops, with less side effects compared to the first generation drugs. Third generation inhibitors have been developed by using the tail approach, but they did not reach the clinics yet. The most promising such derivatives are the sulfonamides incorporating either tails with nitric oxide releasing moieties or hybrid drugs possessing prostaglandin (PG) F agonist moieties in their molecules. Recently, the dithiocarbamates have also been described as CAIs possessing IOP lowering effects in animal models of glaucoma. CAIs are used alone or in combination with other drugs such as adrenergic agonist/antagonists, or PG analogs, being an important component of the antiglaucoma drugs armamentarium. PMID:24146387

  18. Diazepam binding inhibitor and the endocrine pancreas.

    Science.gov (United States)

    Ostenson, C G; Ahrén, B; Johansson, O; Karlsson, S; Hilliges, M; Efendic, S

    1991-12-01

    Regulation of blood glucose homeostasis is complex. Its major hormonal regulators include insulin, glucagon and somatostatin from the endocrine pancreas. Secretion of these hormones is controlled predominantly by the supply of nutrients in the circulation but also by nerve signals and other peptides. Thus, it is likely that peptides, released from cells of the gut or endocrine pancreas or from peptidergic nerves, affect glucose homeostasis by modulating the secretion of insulin, glucagon and somatostatin. When searching for novel gut peptides with such effects, diazepam binding inhibitor (DBI) was isolated from the porcine small intestine. By immunocytochemistry, DBI has been demonstrated to occur not only in the gut but also in endocrine cells of the pancreatic islets, namely in the somatostatin-producing D-cells in pig and man, and in the glucagon-producing A-cells in rat. Porcine DBI (pDBI; 10(-8)-10(-7) M) has been shown to suppress glucose-stimulated release of insulin from both isolated islets and perfused pancreas of the rat. Furthermore, secretion of insulin stimulated by either the sulfonylurea glibenclamide or the phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (IBMX), was inhibited by the peptide. In contrast, arginine-induced release of insulin was unaffected by pDBI. Moreover, pDBI decreased arginine-induced release of glucagon from the perfused rat pancreas, whereas release of somatostatin was unchanged. Notably, rat DBI, structurally identical with rat acyl-CoA-binding protein, has also been demonstrated to inhibit glucose-stimulated release of insulin in the rat, both in vivo and in vitro. Long-term exposure of cultured fetal rat islets to pDBI (10(-8) M) significantly decreased the synthesis of DNA in islet cells.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1780037

  19. Effects of bisphenol A-related diphenylalkanes on vitellogenin production in male carp (Cyprinus carpio) hepatocytes and aromatase (CYP19) activity in human H295r adrenocortical carcinoma cells

    International Nuclear Information System (INIS)

    The present study investigated the effects of the known xenoestrogen bisphenol A (BPA) relative to eight BPA-related diphenylalkanes on estrogen receptor (ER)-mediated vitellogenin (vtg) production in hepatocytes from male carp (Cyprinus carpio), and on aromatase (CYP19) activity in the human adrenocortical H295R carcinoma cell line. Of the eight diphenylalkanes, only 4,4'-(hexafluoropropylidene)diphenol (BHF) and 2,2'-bis(4-hydroxy-3-methylphenyl)propane (BPRO) induced vtg, i.e., to a maximum of 3% to 4% (at 100 μM) compared with 8% for BPA relative to the maximum induction by 17β-estradiol (E2, 1 μM). Bisphenol A diglycidyl ether (BADGE) was a potent antagonist of vtg production with an IC50 of 5.5 μM, virtually 100% inhibition of vtg at 20 μM, and an inhibitive (IC50) potency about one-tenth that of the known ER antagonist tamoxifen (IC50, 0.6 μM). 2,2'-Diallyl bisphenol A, 4,4'-(1,4-phenylene-diisopropylidene)bisphenol, BPRO, and BHF were much less inhibitory with IC50 concentrations of 20-70 μM, and relative potencies of 0.03 and 0.009 with tamoxifen. Bisphenol ethoxylate showed no anti-estrogenicity (up to 100 μM), and 4,4'-isopropylidene-diphenol diacetate was only antagonistic at 100 μM. When comparing the (anti)estrogenic potencies of these bisphenol A analogues/diphenylalkanes, anti-estrogenicity occurred at lower concentrations than estrogenicity. 4,4'-Isopropylidenebis(2,6-dimethylphenol) (IC50, 2.0 μM) reduced E2-induced (EC50, 100 nM) vtg production due to concentration-dependent cytotoxicity as indicated by a parallel decrease in MTT activity and vtg, whereas the remaining diphenylalkanes did not cause any cytotoxicity relative to controls. None of the diphenylalkanes (up to 100 μM) induced EROD activity indicating that concentration-dependent, CYP1A enzyme-mediated metabolism of E2, or any Ah-receptor-mediated interaction with the ER, was not a likely explanation for the observed anti-estrogenic effects. At concentrations as great as 100

  20. Estudio de análogos de la sulfonanilida que actúan como supresores de la expresión de la aromatasa Study of sulfonanilide analogues acting as suppressants of the aromatase expression

    Directory of Open Access Journals (Sweden)

    Ricardo Vivas-Reyes

    2009-12-01

    Full Text Available Se realizó un estudio tridimensional cuantitativo de relación-estructura con nuevos análogos de la sulfonanilida que actúan como supresores de la expresión y actividad de la aromatasa en células de cáncer de mama, independientemente de la inhibición de la ciclooxigenasa-2 (COX-2. La superposición molecular de los ligandos en la plantilla fue llevada a cabo por el método Database Alignment. El mejor modelo estuvo constituido por la combinación de los campos estérico e hidrofóbico, los cuales arrojaron los siguientes parámetros: q² = 0,613 con siete componentes, R² no validado igual a 0,976, valor de F igual a 81,695; 0,347 y 0,047 para los errores estándar de predicción y estimación, respectivamente. Las contribuciones estérica e hidrofóbica fueron de 50,5 y 49,5% respectivamente. Los datos generados por el presente estudio podrían impulsar el diseño de nuevos y más potentes reguladores selectivos de la expresión de la aromatasa.A three-dimensional quantitative structure-activity relationship study was performed with new Sulfonanilide analogue molecules acting as aromatase expression and activity suppressors in breast cancer cells independent of COX-2 inhibition. The molecular supression of the ligands in the grid was carried out by the DATA-BASE ALIGNMENT method. The best model formed by combining the esteric fields and hydrophobic fields yielded the following parameters: q² = 0.613 with seven components, not validated R² equal to 0.976, with an F value of 81.695, 0.347 and 0.047 for the standard errors of prediction and estimate, respectively. The contribution of esteric and hydrophobic fields was 50.5 and 49.5% respectively. data generated from this study may be used to design new and more potent selective aromatase expression regulators.

  1. Kinase Inhibitors from Marine Sponges

    Directory of Open Access Journals (Sweden)

    Ana Zivanovic

    2011-10-01

    Full Text Available Protein kinases play a critical role in cell regulation and their deregulation is a contributing factor in an increasing list of diseases including cancer. Marine sponges have yielded over 70 novel compounds to date that exhibit significant inhibitory activity towards a range of protein kinases. These compounds, which belong to diverse structural classes, are reviewed herein, and ordered based upon the kinase that they inhibit. Relevant synthetic studies on the marine natural product kinase inhibitors have also been included.

  2. Thrombin Inhibitors from Different Animals

    OpenAIRE

    Tanaka-Azevedo, A. M.; Morais-Zani, K.; Torquato, R. J. S.; A. S. Tanaka

    2010-01-01

    Venous and arterial thromboembolic diseases are still the most frequent causes of death and disability in high-income countries. Clinical anticoagulants are inhibitors of enzymes involved in the coagulation pathway, such as thrombin and factor Xa. Thrombin is a key enzyme of blood coagulation system, activating the platelets, converting the fibrinogen to the fibrin net, and amplifying its self-generation by the activation of factors V, VIII, and XI. Thrombin has long been a target for the dev...

  3. ACE INHIBITORS: A COMPREHENSIVE REVIEW

    OpenAIRE

    Pradeep Kumar Arora* and Ashish Chauhan

    2013-01-01

    Hypertension is a chronic increase in blood pressure, characterized as primary and secondary hypertension. The disorder is associated with various risk factors like obesity, diabetes, age, lack of exercise etc. Hypertension is being treated since ancient times by Ayurvedic, Chinese and Unani medicine. Now various allopathic drugs are available which include diuretics, calcium channel blockers, α-blockers, β-blockers, vasodilators, central sympatholytics and ACE-inhibitors. Non-pharmacological...

  4. Carbonic anhydrase inhibitors drug design.

    Science.gov (United States)

    McKenna, Robert; Supuran, Claudiu T

    2014-01-01

    Inhibition of the metalloenzyme carbonic anhydrase (CA, EC 4.2.1.1) has pharmacologic applications in the field of antiglaucoma, anticonvulsant, antiobesity, and anticancer agents but is also emerging for designing anti-infectives (antifungal and antibacterial agents) with a novel mechanism of action. As a consequence, the drug design of CA inhibitors (CAIs) is a very dynamic field. Sulfonamides and their isosteres (sulfamates/sulfamides) constitute the main class of CAIs which bind to the metal ion in the enzyme active site. Recently the dithiocarbamates, possessing a similar mechanism of action, were reported as a new class of inhibitors. Other families of CAIs possess a distinct mechanism of action: phenols, polyamines, some carboxylates, and sulfocoumarins anchor to the zinc-coordinated water molecule. Coumarins and five/six-membered lactones are prodrug inhibitors, binding in hydrolyzed form at the entrance of the active site cavity. Novel drug design strategies have been reported principally based on the tail approach for obtaining all these types of CAIs, which exploit more external binding regions within the enzyme active site (in addition to coordination to the metal ion), leading thus to isoform-selective compounds. Sugar-based tails as well as click chemistry were the most fruitful developments of the tail approach. Promising compounds that inhibit CAs from bacterial and fungal pathogens, of the dithiocarbamate, phenol and carboxylate types have also been reported. PMID:24146385

  5. Bromodomains and their pharmacological inhibitors.

    Science.gov (United States)

    Gallenkamp, Daniel; Gelato, Kathy A; Haendler, Bernard; Weinmann, Hilmar

    2014-03-01

    Over 60 bromodomains belonging to proteins with very different functions have been identified in humans. Several of them interact with acetylated lysine residues, leading to the recruitment and stabilization of protein complexes. The bromodomain and extra-terminal domain (BET) proteins contain tandem bromodomains which bind to acetylated histones and are thereby implicated in a number of DNA-centered processes, including the regulation of gene expression. The recent identification of inhibitors of BET and non-BET bromodomains is one of the few examples in which effective blockade of a protein-protein interaction can be achieved with a small molecule. This has led to major strides in the understanding of the function of bromodomain-containing proteins and their involvement in diseases such as cancer and inflammation. Indeed, BET bromodomain inhibitors are now being clinically evaluated for the treatment of hematological tumors and have also been tested in clinical trials for the relatively rare BRD-NUT midline carcinoma. This review gives an overview of the newest developments in the field, with a focus on the biology of selected bromodomain proteins on the one hand, and on reported pharmacological inhibitors on the other, including recent examples from the patent literature. PMID:24497428

  6. The burden of inhibitors in haemophilia patients.

    Science.gov (United States)

    Walsh, Christopher E; Jiménez-Yuste, Víctor; Auerswald, Guenter; Grancha, Salvador

    2016-08-31

    The burden of disease in haemophilia patients has wide ranging implications for the family and to society. There is evidence that having a current inhibitor increases the risk of morbidity and mortality. Morbidity is increased by the inability to treat adequately and its consequent disabilities, which then equates to a poor quality of life compared with non-inhibitor patients. The societal cost of care, or `burden of inhibitors', increases with the ongoing presence of an inhibitor. Therefore, it is clear that successful eradication of inhibitors by immune tolerance induction (ITI) is the single most important milestone one can achieve in an inhibitor patient. The type of factor VIII (FVIII) product used in ITI regimens varies worldwide. Despite ongoing debate, there is in vitro and retrospective clinical evidence to support the use of plasma-derived VWF-containing FVIII concentrates in ITI regimens in order to achieve early and high inhibitor eradication success rates. PMID:27528280

  7. HIV-1 protease inhibitor mutations affect the development of HIV-1 resistance to the maturation inhibitor bevirimat

    Czech Academy of Sciences Publication Activity Database

    Fun, A.; Maarseveen van, N. M.; Pokorná, Jana; Maas, R. E.; Schipper, P. J.; Konvalinka, Jan; Nijhuis, M.

    2011-01-01

    Roč. 8, č. 70 (2011), s. 1-12. ISSN 1742-4690 Grant ostatní: European Union(XE) LWSHP-CT-2007-037693 Institutional research plan: CEZ:AV0Z40550506 Keywords : immunodeficiency-virus type-1 * gag spacer peptide-1 * replication capacity * compensatory mutations * cleavage sites Subject RIV: CE - Biochemistry Impact factor: 6.470, year: 2011

  8. Combining oral contraceptives with a natural nuclear factor-kappa B inhibitor for the treatment of endometriosis-related pain

    Directory of Open Access Journals (Sweden)

    Maia H Jr

    2013-12-01

    Full Text Available Hugo Maia Jr,1–3 Clarice Haddad,3 Julio Casoy3 1Department of Gynecology and Obstetrics, School of Medicine, Federal University of Bahia, 2Itaigara Memorial Day Hospital, 3Centro de Pesquisas e Assistência em Reprodução Humana (CEPARH, Salvador, Bahia, Brazil Abstract: Endometriosis is a chronic disease in which a persistent state of heightened inflammation is maintained by nuclear factor-kappa B (NF-κB activation. The progestins present in oral contraceptives are potent inhibitors of NF-κB translocation to cell nuclei, while Pycnogenol® (Pinus pinaster acts by blocking post-translational events. In this study, the effects of Pycnogenol on pain scores were investigated in patients with endometriosis using oral contraceptives containing either gestodene or drospirenone in extended regimens. Pain scores were determined using a visual analog scale before and after 3 months of treatment. Oral contraceptives, used alone (groups 1 and 3 or in association with Pycnogenol (groups 2 and 4, resulted in significant decreases in pain scores after 3 months of treatment; however, this reduction was significantly greater in the groups using oral contraceptives + Pycnogenol (groups 2 and 4 compared with those using oral contraceptives alone (groups 1 and 3. In the groups using oral contraceptives alone, 50% of patients became pain-free by the end of the third month of treatment. These results suggest that Pycnogenol increases the efficacy of oral contraceptives for the treatment of endometriosis-related pain. Keywords: Pycnogenol®, aromatase, endometriosis, nuclear factor-kappa B

  9. Protein synthesis and auxin-induced growth: inhibitor studies

    Energy Technology Data Exchange (ETDEWEB)

    Bates, G.T.; Cleland, R.E.

    1979-01-01

    We have compared the effects of cycloheximide (CHI) and two other rapid and effective inhibitors of protein synthesis, pactamycin and 2-(4-methyl-2,6-dinitroanilino)-N-methyl proprionamide (MDMP), on protein synthesis, respiration, auxin-induced growth and H/sup +/-excretion of Avena sativa L. coleoptiles. All three compounds inhibit protein synthesis without affecting respiration. The effectiveness of the inhibitors against H/sup +/-excretion and growth correlates with their ability to inhibit protein synthesis. Both CHI and MDMP inhibit auxin-induced H/sup +/-excretion after a latent period of 5 to 8 min, and inhibit growth after a 8 to 10 min lag. These results support the idea that continued protein synthesis is required in the initial stages of the growth-promoting action of auxin.

  10. Inhibitors of 17beta-hydroxysteroid dehydrogenase type 1.

    Science.gov (United States)

    Brozic, P; Lanisnik Risner, T; Gobec, S

    2008-01-01

    Carcinogenesis of hormone-related cancers involves hormone-stimulated cell proliferation, which increases the number of cell divisions and the opportunity for random genetic errors. In target tissues, steroid hormones are interconverted between their potent, high affinity forms for their respective receptors and their inactive, low affinity forms. One group of enzymes responsible for these interconversions are the hydroxysteroid dehydrogenases, which regulate ligand access to steroid receptors and thus act at a pre-receptor level. As part of this group, the 17beta-hydroxysteroid dehydrogenases catalyze either oxidation of hydroxyl groups or reduction of keto groups at steroid position C17. The thoroughly characterized 17beta-hydroxysteroid dehydrogenase type 1 activates the less active estrone to estradiol, a potent ligand for estrogen receptors. This isoform is expressed in gonads, where it affects circulating levels of estradiol, and in peripheral tissue, where it regulates ligand occupancy of estrogen receptors. Inhibitors of 17beta-hydroxysteroid dehydrogenase type 1 are thus highly interesting potential therapeutic agents for the control of estrogen-dependent diseases such as endometriosis, as well as breast and ovarian cancers. Here, we present the review on the recent development of inhibitors of 17beta-hydroxysteroid dehydrogenase type 1 published and patented since the previous review of 17beta-hydroxysteroid dehydrogenase inhibitors of Poirier (Curr. Med. Chem., 2003, 10, 453). These inhibitors are divided into two separate groups according to their chemical structures: steroidal and non-steroidal 17beta-hydroxysteroid dehydrogenase type 1 inhibitors. Their estrogenic/ proliferative activities and selectivities over other 17beta-hydroxysteroid dehydrogenases that are involved in local regulation of estrogen action (types 2, 7 and 12) are also presented. PMID:18220769

  11. Diagnosis and treatment of hereditary angioedema with normal C1 inhibitor

    Directory of Open Access Journals (Sweden)

    Bork Konrad

    2010-07-01

    Full Text Available Abstract Until recently it was assumed that hereditary angioedema is a disease that results exclusively from a genetic deficiency of the C1 inhibitor. In 2000, families with hereditary angioedema, normal C1 inhibitor activity and protein in plasma were described. Since then numerous patients and families with that condition have been reported. Most of the patients by far were women. In many of the affected women, oral contraceptives, hormone replacement therapy containing estrogens, and pregnancies triggered the clinical symptoms. Recently, in some families mutations in the coagulation factor XII (Hageman factor gene were detected in the affected persons.

  12. Pain, Affect, and Attachment

    OpenAIRE

    Carl Eduard Scheidt; Elisabeth Waller

    2015-01-01

    Various psychodynamic processes may underlie the development of psychogenic pain disorder such as conversion, the displacement of affect, or narcissistic defenses. However, many of the processes suggested are related to a disorder of affect regulation. The term affect regulation in psychoanalytic literature refers to phenomena which are often described by the concept of alexithymia. Empirical observations suggest that alexithymia is correlated to insecure attachment, especially an insecure di...

  13. The affect structure revisited

    OpenAIRE

    Elefant-Yanni, Véronique Rica; Victoria-Feser, Maria-Pia

    2005-01-01

    In affective psychology, there is a persistent controversy about the number, the nature and the definition of the affect structure dimensions. Responding to the methodological criticisms addressed to the preceding studies, we conciliated the principal theories regarding the affect structure with the same experimental setting. In particular, using the semantic items all around the circumplex we found three bipolar independent dimensions and using only the PANAS semantic items, we found two uni...

  14. Xylanase inhibitors bind to nonstarch polysaccharides.

    Science.gov (United States)

    Fierens, Ellen; Gebruers, Kurt; Courtin, Christophe M; Delcour, Jan A

    2008-01-23

    This study is an in-depth investigation of the interaction between polysaccharides and the proteinaceous xylanase inhibitors, Triticum aestivum xylanase inhibitor (TAXI), xylanase inhibitor protein (XIP), and thaumatin-like xylanase inhibitor (TLXI). The binding affinities of all three known types of xylanase inhibitors from wheat are studied by measuring the residual xylanase inhibition activity after incubation of the inhibitors in the presence of different polysaccharides, such as beta-glucans and (arabino)xylans. The binding affinities of all three xylanase inhibitors for (arabino)xylans increased with a decreasing arabinose/xylose ratio (A/X ratio). This phenomenon was observed both with water-extractable and water-unextractable (arabino)xylans. The inhibitors also interacted with different soluble and insoluble beta-glucans. None of the inhibitors tested had the ability to hydrolyze the polysaccharides investigated. The present findings contribute to the unraveling of the function of xylanase inhibitors in nature and to the prediction of the effect of added xylanases in cereal-based biotechnological processes, such as bread making and gluten-starch separation. PMID:18092758

  15. An alpha-glucosidase inhibitor from an endophytic Cladosporium sp. with potential as a biocontrol agent.

    Science.gov (United States)

    Singh, Bahaderjeet; Kaur, Tamanreet; Kaur, Sanehdeep; Manhas, Rajesh K; Kaur, Amarjeet

    2015-02-01

    This study highlights the importance of alpha-glucosidase inhibitors as mechanisms for endophyte-mediated resistance to insect pests. One of the major benefits which endophytes confer on plants is providing resistance against insect pests. This built-in defense mechanism of the plant can be used for exploring ecofriendly strategies for pest control. In the present study, 34 endophytic fungi were isolated from Tinospora cordifolia and screened for their ability to produce alpha-glucosidase inhibitors. Maximum inhibitory activity was observed in an isolate from T. cordifolia (TN-9S), identified to be Cladosporium sp. The inhibitor was purified using chromatographic techniques. The insecticidal activity of the purified inhibitor was evaluated against Spodoptera litura. The inhibitor induced a significant mortality in the larvae of S. litura and adversely affected its survival and development. It also inhibited the activity of α-glycosidases in vivo in the gut of the larvae. The purified inhibitor was determined to be a phenolic compound with amine groups, demonstrating a noncompetitive type of inhibition in vitro. The production of the inhibitor was optimized. Response surface methodology (RSM) analysis revealed a significant interaction between dextrose and malt extract, with first-order effect of pH. PMID:25432333

  16. Localization of aromatase in the nervous system, Hatschek's pit and gonad of amphioxus by in situ hybridization and immunocytochemistry%芳香化酶在文昌鱼神经系统、哈氏窝和性腺特异性定位:原位杂交和免疫细胞化学研究

    Institute of Scientific and Technical Information of China (English)

    方永强; 翁幼竹; 黄威权; 孙岚

    2003-01-01

    芳香化酶活性发现在脊椎动物脑、脑垂体和性腺中,但在文昌鱼脑和哈氏窝的组织特异性定位尚无可利用资料.本文用免疫细胞化学和原位杂交技术,首次发现芳香化酶活性组织特异性定位在幼年和性腺发育不同时期雌、雄文昌鱼神经系统(脑和脊髓)、轮器、哈氏窝和性腺中.芳香化酶蛋白和转录物在前脑、中脑、脊髓、轮器和哈氏窝十分丰富,而后脑、早期卵巢和精巢不够丰富;没有芳香化酶表达的部位是哈氏窝另两种细胞(不规则形细胞和带纤毛粘液细胞)以及成熟卵巢和精巢;芳香化酶免疫活性物质分布在胞质,核为阴性.芳香化酶在文昌鱼神经系统、哈氏窝和性腺的分布模式与低等脊椎动物中的分布模式极为类似,尤其是芳香化酶在脑内调节哈氏窝分泌活动的神经内分泌中枢表达,并形成类似脊椎动物的文昌鱼原始的脑-芳香化酶调节系统.这些结果有力地证明,文昌鱼脑和哈氏窝高水平的芳香化酶活性像在其它脊椎动物中一样,对局部介导睾酮芳香化起着关键作用,同时还可能影响脑-芳香化酶系统参与调节哈氏窝的分泌活动[动物学报49(6):800~806,2003].%Aromatase activity has been found in the brain and pituitary as well as gonads of vertebrates, but no information is available on the specific localization in the brain and Hatschek's pit (primitive pituitary) of amphioxus (Branchios-toma belcheri). Using immunocytochemistry and in situ hybridization, we studied definitive tissue specific localization of aromatase in the nervous system (brain and spinal cord), wheel organ, Hatschek's pit and gonads at young and adult female and male amphioxus at different stages of gonadal development. Aromatase protein and its mRNA were abundant in the forebrain, midbrain, spinal cord, wheel organ and Hatschek's pit, but not abundant in the hindbrain or early ovary and testis. No aromatase expression

  17. Modulation of C1-Inhibitor and Plasma Kallikrein Activities by Type IV Collagen

    Directory of Open Access Journals (Sweden)

    Sriram Ravindran

    2012-01-01

    Full Text Available The contact system of coagulation can be activated when in contact with biomaterials. As collagen is being tested in novel biomaterials in this study, we have investigated how type IV collagen affects plasma kallikrein and C1-inhibitor. Firstly, we showed C1-inhibitor binds to type IV collagen with a Kd of 0.86 μM. The effects of type IV collagen on plasma kallikrein, factor XIIa, and β-factor XIIa activity and on C1-inhibitor function were determined. Factor XIIa rapidly lost activity in the presence of type IV collagen, whereas plasma kallikrein and β-factor XIIa were more stable. The rate of inhibition of plasma kallikrein by C1-inhibitor was decreased by type IV collagen in a dose-dependent manner. These studies could be relevant to the properties of biomaterials, which contain collagen, and should be considered in the testing for biocompatibility.

  18. Management of side effects of mTOR inhibitors in tuberous sclerosis patients.

    Science.gov (United States)

    Sadowski, Krzysztof; Kotulska, Katarzyna; Jóźwiak, Sergiusz

    2016-06-01

    mTOR inhibitors represent a relatively new therapeutic option in the management of patients affected by tuberous sclerosis complex (TSC). Randomized clinical trials support the use of everolimus in the treatment of subependymal giant cell astrocytomas (SEGA) and renal angiomyolipomas (AML) related to TSC. Accumulating data suggest also systemic disease-modifying potential of mTOR inhibitors. Given that increasing number of patients with TSC receive mTOR inhibitors, the issue of adverse events associated with this therapy becomes practically important. In the present study we provide the overview of clinical manifestations and therapeutic options for the most common adverse events related to mTOR inhibitors in TSC patients. PMID:26891243

  19. Affectivity and race

    DEFF Research Database (Denmark)

    This book presents new empirical studies of social difference in the Nordic welfare states, in order to advance novel theoretical perspectives on the everyday practices and macro-politics of race and gender in multi-ethnic societies. With attention to the specific political and cultural landscapes...... of the Nordic countries, Affectivity and Race draws on a variety of sources, including television programmes, news media, fictional literature, interviews, ethnographic observations, teaching curricula and policy documents, to explore the ways in which ideas about affectivity and emotion afford new...... insights into the experience of racial difference and the unfolding of political discourses on race in various social spheres. Organised around the themes of the politicisation of race through affect, the way that race produces affect and the affective experience of race, this interdisciplinary collection...

  20. Affectivity in the Liminal

    DEFF Research Database (Denmark)

    Thomassen, Bjørn

    alternative interpretations of what liminality is, or could be, taking it to territories distant from its place of origin, quite the contrary: we are moving the concept back to its rightful place in intellectual history and back to the core of its significance, back to the centre of human emotions trembling......In this paper I propose a return to the work of Arnold van Gennep, in order to briefly discuss how the terms of liminality and affectivity were always already connected. By linking the concept of liminality that van Gennep made famous to affectivity, we are actually not proposing new and...... at the threshold. The paper contains three sections: a) liminality and affectivity in van Gennep’s life; b) liminality and affectivity as a theme in his work; c) liminality and affectivity as developed in the early reception of his work....

  1. Inhibitors of Acetylcholinesterase and Butyrylcholinesterase Meet Immunity

    OpenAIRE

    Miroslav Pohanka

    2014-01-01

    Acetylcholinesterase (AChE) inhibitors are widely used for the symptomatic treatment of Alzheimer’s disease and other dementias. More recent use is for myasthenia gravis. Many of these inhibitors interact with the second known cholinesterase, butyrylcholinesterase (BChE). Further, evidence shows that acetylcholine plays a role in suppression of cytokine release through a “cholinergic anti-inflammatory pathway” which raises questions about the role of these inhibitors in the immune system. Thi...

  2. Small molecule phagocytosis inhibitors for immune cytopenias.

    Science.gov (United States)

    Neschadim, Anton; Kotra, Lakshmi P; Branch, Donald R

    2016-08-01

    Immune cytopenias are conditions characterized by low blood cell counts, such as platelets in immune thrombocytopenia (ITP) and red blood cells in autoimmune hemolytic anemia (AIHA). Chronic ITP affects approximately 4 in 100,000 adults annually while AIHA is much less common. Extravascular phagocytosis and massive destruction of autoantibody-opsonized blood cells by macrophages in the spleen and liver are the hallmark of these conditions. Current treatment modalities for ITP and AIHA include the first-line use of corticosteroids; whereas, IVIg shows efficacy in ITP but not AIHA. One main mechanism of action by which IVIg treatment leads to the reduction in platelet destruction rates in ITP is thought to involve Fcγ receptor (FcγR) blockade, ultimately leading to the inhibition of extravascular platelet phagocytosis. IVIg, which is manufactured from the human plasma of thousands of donors, is a limited resource, and alternative treatments, particularly those based on bioavailable small molecules, are needed. In this review, we overview the pathophysiology of ITP, the role of Fcγ receptors, and the mechanisms of action of IVIg in treating ITP, and outline the efforts and progress towards developing novel, first-in-class inhibitors of phagocytosis as synthetic, small molecule substitutes for IVIg in ITP and other conditions where the pathobiology of the disease involves phagocytosis. PMID:27296447

  3. Cyclooxygenase-2 inhibition reduces stress-induced affective pathology

    Science.gov (United States)

    Gamble-George, Joyonna Carrie; Baldi, Rita; Halladay, Lindsay; Kocharian, Adrina; Hartley, Nolan; Silva, Carolyn Grace; Roberts, Holly; Haymer, Andre; Marnett, Lawrence J; Holmes, Andrew; Patel, Sachin

    2016-01-01

    Mood and anxiety disorders are the most prevalent psychiatric conditions and are exacerbated by stress. Recent studies have suggested cyclooxygenase-2 (COX-2) inhibition could represent a novel treatment approach or augmentation strategy for affective disorders including anxiety disorders and major depression. We show that traditional COX-2 inhibitors and a newly developed substrate-selective COX-2 inhibitor (SSCI) reduce a variety of stress-induced behavioral pathologies in mice. We found that these behavioral effects were associated with a dampening of neuronal excitability in the basolateral amygdala (BLA) ex vivo and in vivo, and were mediated by small-conductance calcium-activated potassium (SK) channel and CB1 cannabinoid receptor activation. Taken together, these data provide further support for the potential utility of SSCIs, as well as traditional COX-2 inhibitors, as novel treatment approaches for stress-related psychiatric disorders. DOI: http://dx.doi.org/10.7554/eLife.14137.001 PMID:27162170

  4. Calcineurin inhibitor minimisation versus continuation of calcineurin inhibitor treatment for liver transplant recipients

    DEFF Research Database (Denmark)

    Penninga, Luit; Wettergren, Andre; Chan, An-Wen;

    2012-01-01

    The therapeutic success of liver transplantation has been largely attributable to the development of effective immunosuppressive treatment regimens. In particular, calcineurin inhibitors were essential in reducing acute rejection and improving early survival. Currently, more than 90% of all liver...... transplant recipients are treated with the calcineurin inhibitor cyclosporine or tacrolimus. Unfortunately, calcineurin inhibitors cause adverse events, such as nephrotoxicity, and because of this, minimisation (reduction and withdrawal) regimens of calcineurin inhibitor have been developed and studied...

  5. Development of covalent inhibitors that can overcome resistance to first-generation FGFR kinase inhibitors

    OpenAIRE

    Tan, Li; Wang, Jun; Tanizaki, Junko; Huang, Zhifeng; Aref, Amir R.; Rusan, Maria; Zhu, Su-Jie; Zhang, Yiyun; Ercan, Dalia; Liao, Rachel G.; Capelletti, Marzia; Zhou, Wenjun; Hur, Wooyoung; Kim, NamDoo; Sim, Taebo

    2014-01-01

    Inhibitors of the FGF receptors (FGFRs) are currently under clinical investigation for the treatment of various cancers. All currently approved kinase inhibitors eventually are rendered useless by the emergence of drug-resistant tumors. We used structure-based drug design to develop the first, to our knowledge, selective, next-generation covalent FGFR inhibitors that can overcome the most common form of kinase inhibitor resistance, the mutation of the so-called “gatekeeper” residue located in...

  6. Normal human neutrophils are a source of a specific interleukin 1 inhibitor

    International Nuclear Information System (INIS)

    In the course of the study on neutrophil production of an interleukin 1 (IL 1)-like factor, it was found that the addition of polymorphonuclear neutrophils (PMN) to monocytes cultured in the presence of zymosan resulted in decreased IL 1 activity of the resultant supernatant, suggesting that PMN may contain an inhibitor of IL 1. The objective of this investigation was to study this IL 1 inhibitor which normal human PMN contain. The inhibitor is constitutively present in the PMN because 0 hr PMN lysates and unstimulated PMN supernatants also show inhibitory activity. The PMN inhibitor inhibits IL 1 (crude and partially purified) in a dose-response manner and does not affect basal [3H]thymidine incorporation in the presence or absence of PHA-P. The PMN inhibitor does not have any effect on interleukin 2 (IL 2)-induced proliferation of the IL 2-dependent CTLL cells. The inhibitor can be generated in the absence of serum and is not produced as a result of proteolytic activity from PMN enzymes. The inhibitor is heat-labile and is most stable at neutral pH. Gel filtration studies on Sephadex G-200 indicate that the inhibitor is heterogeneous in size. Two inhibitory peaks, at 45,000 to 70,000 m.w. and at greater than 160,000 m.w., were observed. When zymosan-stimulated PMN supernatant was chromatographed, there was separation of inhibitory factor from a 17,000 m.w. proliferating factor. Presence of this PMN inhibitor may be important in negative regulation of IL 1

  7. Mechanistic studies of the corrosion inhibitor oleic imidazoline

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, A.; Osborne, C.; Webster, S.; Klenerman, D.; Joseph, M.; Ostovar, P.; Doyle, M. (British Petroleum Co. Ltd., Sunbury-on-Thames (United Kingdom). BP Research Centre)

    1994-02-01

    An investigation of the mode of action of the corrosion inhibitor oleic imidazoline has been carried out using corrosion testing, second harmonic generation at surfaces and molecular modelling techniques. Selected variations to the molecular structure have been made to elucidate the relevant roles of the constituent parts of the molecule. Results show that the molecule is primarily bonding through the five-membered nitrogen ring which is lying planar to the metal surface, that the long hydrocarbon chain is playing an important role in the mechanism of inhibition, and that varying the chemistry of the pendant side chain does not affect the performance of the molecule to a major extent. (Author)

  8. Discovery of indole inhibitors of chemokine receptor 9 (CCR9).

    Science.gov (United States)

    Pandya, Bhaumik A; Baber, Christian; Chan, Audrey; Chamberlain, Brian; Chandonnet, Haoqun; Goss, Jennifer; Hopper, Timothy; Lippa, Blaise; Poutsiaka, Katherine; Romero, Jan; Stucka, Sabrina; Varoglu, Mustafa; Zhang, Jing; Zhang, Xin

    2016-07-15

    Irritable bowel diseases (IBD) such as Crohn's disease (CD) and ulcerative colitis (UC) are serious chronic diseases affecting millions of patients worldwide. Studies of human chemokine biology has suggested C-C chemokine receptor 9 (CCR9) may be a key mediator of pro-inflammatory signaling. Discovery of agents that inhibit CCR9 may lead to new therapies for CD and UC patients. Herein we describe the evolution of a high content screening hit (1) into potent inhibitors of CCR9, such as azaindole 12. PMID:27256913

  9. Dynamics of CYP51: implications for function and inhibitor design

    OpenAIRE

    Yu, Xiaofeng; Cojocaru, Vlad; Mustafa, Ghulam; Salo-Ahen, Outi M. H.; Lepesheva, Galina I.; Wade, Rebecca C.

    2015-01-01

    Sterol 14α-demethylase (cytochrome P450 family 51 (CYP51)) is an essential enzyme occurring in all biological kingdoms. In eukaryotes, it is located in the membrane of the endoplasmic reticulum. Selective inhibitors of trypanosomal CYP51s that do not affect the human CYP51 have been discovered in vitro and found to cure acute and chronic mouse Chagas disease without severe side effects in vivo. Crystal structures indicate that CYP51 may be more rigid than most CYPs, and it has been proposed t...

  10. Pain, Affect, and Attachment

    Directory of Open Access Journals (Sweden)

    Carl Eduard Scheidt

    2015-03-01

    Full Text Available Various psychodynamic processes may underlie the development of psychogenic pain disorder such as conversion, the displacement of affect, or narcissistic defenses. However, many of the processes suggested are related to a disorder of affect regulation. The term affect regulation in psychoanalytic literature refers to phenomena which are often described by the concept of alexithymia. Empirical observations suggest that alexithymia is correlated to insecure attachment, especially an insecure dismissing representation of attachment. Psychodynamic psychotherapy in psychogenic pain disorder should focus on the reintegration of split-off affects which may provoke intensive counter-transference and which in order to be used therapeutically must be linked to attachment experiences within and outside of the therapeutic relationship.

  11. Colors Can Affect Us!

    Institute of Scientific and Technical Information of China (English)

    张俊斌

    2006-01-01

    Different colors affect us differently.The following will show us how they work. Experiment proves that math problems worked on yellow paper have fewer mistakes than problems written on other colors of paper.

  12. Cysteine Protease Inhibitors as Chemotherapy: Lessons from a Parasite Target

    Science.gov (United States)

    Selzer, Paul M.; Pingel, Sabine; Hsieh, Ivy; Ugele, Bernhard; Chan, Victor J.; Engel, Juan C.; Bogyo, Matthew; Russell, David G.; Sakanari, Judy A.; McKerrow, James H.

    1999-09-01

    Papain family cysteine proteases are key factors in the pathogenesis of cancer invasion, arthritis, osteoporosis, and microbial infections. Targeting this enzyme family is therefore one strategy in the development of new chemotherapy for a number of diseases. Little is known, however, about the efficacy, selectivity, and safety of cysteine protease inhibitors in cell culture or in vivo. We now report that specific cysteine protease inhibitors kill Leishmania parasites in vitro, at concentrations that do not overtly affect mammalian host cells. Inhibition of Leishmania cysteine protease activity was accompanied by defects in the parasite's lysosome/endosome compartment resembling those seen in lysosomal storage diseases. Colocalization of anti-protease antibodies with biotinylated surface proteins and accumulation of undigested debris and protease in the flagellar pocket of treated parasites were consistent with a pathway of protease trafficking from flagellar pocket to the lysosome/endosome compartment. The inhibitors were sufficiently absorbed and stable in vivo to ameliorate the pathology associated with a mouse model of Leishmania infection.

  13. COX-2 inhibitors are contraindicated for treatment of combined injury.

    Science.gov (United States)

    Jiao, W; Kiang, J G; Cary, L; Elliott, T B; Pellmar, T C; Ledney, G D

    2009-12-01

    Casualties of radiation dispersal devices, nuclear detonation or major ionizing radiation accidents, in addition to radiation exposure, may sustain physical and/or thermal trauma. Radiation exposure plus additional tissue trauma is known as combined injury. There are no definitive therapeutic agents. Cyclooxygenase-2 (COX-2), an inducible enzyme expressed in pathological disorders and radiation injury, plays an important role in inflammation and the production of cytokines and prostaglandin E(2) (PGE(2)) and could therefore affect the outcome for victims of combined injury. The COX-2 inhibitors celecoxib and meloxicam were evaluated for their therapeutic value against combined injury in mice. In survival studies, the COX-2 inhibitors had no beneficial effect on 30-day survival, wound healing or body weight gain after radiation injury alone or after combined injury. Meloxicam accelerated death in both wounded and combined injury mice. These drugs also induced severe hepatic toxicity, exaggerated inflammatory processes, and did not enhance hematopoietic cell regeneration. This study points to potential contraindications for use of COX-2 inhibitors in patients undergoing therapy for radiation injury and combined injury. PMID:19929415

  14. Phosphatidylinositol 3-kinase inhibitors block differentiation of skeletal muscle cells.

    Science.gov (United States)

    Kaliman, P; Viñals, F; Testar, X; Palacín, M; Zorzano, A

    1996-08-01

    Skeletal muscle differentiation involves myoblast alignment, elongation, and fusion into multinucleate myotubes, together with the induction of regulatory and structural muscle-specific genes. Here we show that two phosphatidylinositol 3-kinase inhibitors, LY294002 and wortmannin, blocked an essential step in the differentiation of two skeletal muscle cell models. Both inhibitors abolished the capacity of L6E9 myoblasts to form myotubes, without affecting myoblast proliferation, elongation, or alignment. Myogenic events like the induction of myogenin and of glucose carrier GLUT4 were also blocked and myoblasts could not exit the cell cycle, as measured by the lack of mRNA induction of p21 cyclin-dependent kinase inhibitor. Overexpresssion of MyoD in 10T1/2 cells was not sufficient to bypass the myogenic differentiation blockade by LY294002. Upon serum withdrawal, 10T1/2-MyoD cells formed myotubes and showed increased levels of myogenin and p21. In contrast, LY294002-treated cells exhibited none of these myogenic characteristics and maintained high levels of Id, a negative regulator of myogenesis. These data indicate that whereas phosphatidylinositol 3-kinase is not indispensable for cell proliferation or in the initial events of myoblast differentiation, i.e. elongation and alignment, it appears to be essential for terminal differentiation of muscle cells. PMID:8702591

  15. PLK-1 Targeted Inhibitors and Their Potential against Tumorigenesis

    Directory of Open Access Journals (Sweden)

    Shiv Kumar

    2015-01-01

    Full Text Available Mitotic kinases are the key components of the cell cycle machinery and play vital roles in cell cycle progression. PLK-1 (Polo-like kinase-1 is a crucial mitotic protein kinase that plays an essential role in both the onset of G2/M transition and cytokinesis. The overexpression of PLK-1 is strongly correlated with a wide spectrum of human cancers and poor prognosis. The (siRNA-mediated depletion of PLK-1 arrests tumor growth and triggers apoptosis in cancer cells without affecting normal cells. Therefore, PLK-1 has been selected as an attractive anticancer therapeutic drug target. Some small molecules have been discovered to target the catalytic and noncatalytic domains of PLK-1. These domains regulate the catalytic activation and subcellular localization of PLK-1. However, while PLK-1 inhibitors block tumor growth, they have been shown to cause severe adverse complications, such as toxicity, neutropenia, and bone marrow suppression during clinical trials, due to a lack of selectivity and specificity within the human kinome. To minimize these toxicities, inhibitors should be tested against all protein kinases in vivo and in vitro to enhance selectivity and specificity against targets. Here, we discuss the potency and selectivity of PLK-1-targeted inhibitors and their molecular interactions with PLK-1 domains.

  16. The direct thrombin inhibitor hirudin.

    Science.gov (United States)

    Greinacher, Andreas; Warkentin, Theodore E

    2008-05-01

    This review discusses the pharmacology and clinical applications of hirudin, a bivalent direct thrombin inhibitor (DTI). Besides the current major indication for hirudin--anticoagulation of patients with heparin-induced thrombocytopenia (HIT)--the experience with hirudin in other indications, especially acute coronary syndromes, are briefly presented. Hirudins have been formally studied prior to their regulatory approval; however, important information on their side effects and relevant preventative measures only became available later. Therefore, current recommendations and dosing schedules for hirudin differ considerably from the information given in the package inserts. Drawbacks of hirudin and important precautions for avoiding potential adverse effects are discussed in detail in the third part of this review. PMID:18449411

  17. Angiotensin converting enzyme inhibitor induced hyperkalaemic paralysis

    OpenAIRE

    Dutta., D; Fischler, M; McClung, A

    2001-01-01

    Secondary hyperkalaemic paralysis is a rare condition often mimicking the Guillain-Barré syndrome. There have been a few case reports of hyperkalaemia caused by renal failure, trauma, and drugs where the presentation has been with muscle weakness. A case of hyperkalaemic paralysis caused by an angiotensin converting enzyme inhibitor is reported.


Keywords: hyperkalaemia; paralysis; ACE inhibitors

  18. Screening for potential inhibitors of influenza neuraminidase

    Institute of Scientific and Technical Information of China (English)

    Ai-linLIU; Guan-huaDU

    2004-01-01

    AIM: Applying the assay method of neuraminidase(NA) activity established for high throughput screening to find novel inhibitors of influenza virus NA. METHODS: Firstly, a virtual screening strategy was applied to our compound database to select drug-like compounds, and then a high throughput screening model of NA inhibitor was applied to test these compounds. RESULTS:

  19. Clinical utility of the oral JAK inhibitor tofacitinib in the treatment of rheumatoid arthritis

    OpenAIRE

    Cutolo M; Meroni M

    2013-01-01

    Maurizio Cutolo, Marianna Meroni Research Laboratories and Academic Division of Clinical Rheumatology, Department of Internal Medicine, University of Genova, Genova, Italy Abstract: Immune/inflammatory cells act in rheumatoid arthritis (RA)-affected patients by synthesizing several inflammatory mediators, including cytokines that initiate intracellular signaling. Recently, small molecule inhibitors of transduction and transcription signals that influence the intracellular pathways (such as t...

  20. Histone deacetylase inhibitors (HDACIs: multitargeted anticancer agents

    Directory of Open Access Journals (Sweden)

    Ververis K

    2013-02-01

    Full Text Available Katherine Ververis,1 Alison Hiong,1 Tom C Karagiannis,1,* Paul V Licciardi2,*1Epigenomic Medicine, Alfred Medical Research and Education Precinct, 2Allergy and Immune Disorders, Murdoch Childrens Research Institute, Melbourne, VIC, Australia*These authors contributed equally to this workAbstract: Histone deacetylase (HDAC inhibitors are an emerging class of therapeutics with potential as anticancer drugs. The rationale for developing HDAC inhibitors (and other chromatin-modifying agents as anticancer therapies arose from the understanding that in addition to genetic mutations, epigenetic changes such as dysregulation of HDAC enzymes can alter phenotype and gene expression, disturb homeostasis, and contribute to neoplastic growth. The family of HDAC inhibitors is large and diverse. It includes a range of naturally occurring and synthetic compounds that differ in terms of structure, function, and specificity. HDAC inhibitors have multiple cell type-specific effects in vitro and in vivo, such as growth arrest, cell differentiation, and apoptosis in malignant cells. HDAC inhibitors have the potential to be used as monotherapies or in combination with other anticancer therapies. Currently, there are two HDAC inhibitors that have received approval from the US FDA for the treatment of cutaneous T-cell lymphoma: vorinostat (suberoylanilide hydroxamic acid, Zolinza and depsipeptide (romidepsin, Istodax. More recently, depsipeptide has also gained FDA approval for the treatment of peripheral T-cell lymphoma. Many more clinical trials assessing the effects of various HDAC inhibitors on hematological and solid malignancies are currently being conducted. Despite the proven anticancer effects of particular HDAC inhibitors against certain cancers, many aspects of HDAC enzymes and HDAC inhibitors are still not fully understood. Increasing our understanding of the effects of HDAC inhibitors, their targets and mechanisms of action will be critical for the

  1. Affective responses to dance.

    Science.gov (United States)

    Christensen, Julia F; Pollick, Frank E; Lambrechts, Anna; Gomila, Antoni

    2016-07-01

    The objective of the present work was the characterization of mechanisms by which affective experiences are elicited in observers when watching dance movements. A total of 203 dance stimuli from a normed stimuli library were used in a series of independent experiments. The following measures were obtained: (i) subjective measures of 97 dance-naïve participants' affective responses (Likert scale ratings, interviews); and (ii) objective measures of the physical parameters of the stimuli (motion energy, luminance), and of the movements represented in the stimuli (roundedness, impressiveness). Results showed that (i) participants' ratings of felt and perceived affect differed, (ii) felt and perceived valence but not arousal ratings correlated with physical parameters of the stimuli (motion energy and luminance), (iii) roundedness in posture shape was related to the experience of more positive emotion than edgy shapes (1 of 3 assessed rounded shapes showed a clear effect on positiveness ratings while a second reached trend level significance), (iv) more impressive movements resulted in more positive affective responses, (v) dance triggered affective experiences through the imagery and autobiographical memories it elicited in some people, and (vi) the physical parameters of the video stimuli correlated only weakly and negatively with the aesthetics ratings of beauty, liking and interest. The novelty of the present approach was twofold; (i) the assessment of multiple affect-inducing mechanisms, and (ii) the use of one single normed stimulus set. The results from this approach lend support to both previous and present findings. Results are discussed with regards to current literature in the field of empirical aesthetics and affective neuroscience. PMID:27235953

  2. Potential physiological role of plant glycosidase inhibitors

    DEFF Research Database (Denmark)

    Bellincampi, D.; Carmadella, L.; Delcour, J.A.;

    2004-01-01

    Carbohydrate-active enzymes including glycosidases, transglycosidases, glycosyltransferases, polysaccharide lyases and carbohydrate esterases are responsible for the enzymatic processing of carbohydrates in plants. A number of carbohydrate-active enzymes are produced by microbial pathogens and...... insects responsible of severe crop losses. Plants have evolved proteinaceous inhibitors to modulate the activity of several of these enzymes. The continuing discovery of new inhibitors indicates that this research area is still unexplored and may lead to new exciting developments. To date, the role of the...... inhibitors is not completely understood. Here we review recent results obtained on the best characterised inhibitors, pointing to their possible biological role in vivo. Results recently obtained with plant transformation technology indicate that this class of inhibitors has potential biotechnological...

  3. [Recent development of selective cyclooxygenase-2 inhibitors].

    Science.gov (United States)

    Kawai, Shinichi

    2002-12-01

    Nonsteroidal anti-inflammatory drugs(NSAIDs) are clinically effective against the inflammatory symptoms of rheumatoid arthritis. Recent attention has been focused on selective cyclooxygenase(COX)-2 inhibitors, a type of NSAID that inhibits a subtype of COX. Because of the different actions of COX-1 and COX-2, selective COX-2 inhibitors were expected to reduce adverse reactions such as gastrointestinal disorders. Various clinical studies have confirmed that the efficacy of COX-2 inhibitors for RA is similar to that of conventional NSAIDs, but they cause fewer severe gastrointestinal disorders. The incidence of complications related to renal dysfunction, such as edema and hypertension, is not different. Patients using selective COX-2 inhibitors have recently been reported to show an increase in thrombotic complications such as myocardial infarction. Therefore, more data on adverse events should be collected in the future from large-scale clinical studies to further clarify the actual value of selective COX-2 inhibitors. PMID:12510364

  4. Novel peptide-based protease inhibitors

    DEFF Research Database (Denmark)

    Roodbeen, Renée

    This thesis describes the design and synthesis of peptide-based serine protease inhibitors. The targeted protease, urokinase-type plasminogen activator (uPA) activates plasminogen, which plays a major role in cancer metastasis. The peptide upain-2 (S 1 ,S 12-cyclo-AcCSWRGLENHAAC-NH2) is a highly...... specific inhibitor of uPA. With the aim of creating better inhibitors based on the upain-2 scaffold, the following three strategies were explored: First, it was attempted to predefine the structure of upain-2 in solution by incorporating turn-inducing sequences and peptidomimetics. Additionally...... bond across the ring. The second bridge was made by a disulfide bridge, amide bond formation or via ring-closing metathesis. A, with upain-2 equipotent, bicyclic inhibitor was obtained and its binding to uPA was studied by ITC, NMR and X-ray. The knowledge of how selective inhibitors bind uPA has been...

  5. Combination with γ-secretase inhibitor prolongs treatment efficacy of BRAF inhibitor in BRAF-mutated melanoma cells.

    Science.gov (United States)

    Zhu, Guannan; Yi, Xiuli; Haferkamp, Sebastian; Hesbacher, Sonja; Li, Chunying; Goebeler, Matthias; Gao, Tianwen; Houben, Roland; Schrama, David

    2016-06-28

    Oncogenic triggering of the MAPK pathway in melanocytes results in senescence, and senescence escape is considered as one critical step for melanocytic transformation. In melanoma, induction of a senescent-like state by BRAF-inhibitors (BRAFi) in a fraction of treated cells - instead of killing - contributes to the repression of tumor growth, but may also provide a source for relapse. Here, we demonstrate that NOTCH activation in melanocytes is not only growth-promoting but it also protects these cells against oncogene-induced senescence. In turn, treatment of melanoma cells with an inhibitor of the NOTCH-activating enzyme γ-secretase led to induction of a senescent-like status in a fraction of the cells but overall achieved only a moderate inhibition of melanoma cell growth. However, combination of γ-secretase inhibitor (GSI) with BRAFi markedly increased the treatment efficacy particularly in long-term culture. Moreover, even melanoma cells starting to regrow after continuous BRAFi treatment - the major problem of BRAFi therapy in patients - can still be affected by the combination treatment. Thus, combining GSI with BRAFi increases the therapeutic efficacy by, at least partially, prolonging the senescent-like state of treated cells. PMID:27000992

  6. The Affective Turn

    Directory of Open Access Journals (Sweden)

    Alí Lara

    2013-11-01

    Full Text Available In the last decade studies on affect and emotions have become relevant in the social sciences. This is not just a fad guideline, but instead a simultaneous reader of public life changes and subjective experience, from which it is also being transformed the knowledge production. Such a trend has been known as ‘The Affective Turn’ within the Anglophone Academy. Here we will translate it as ‘El Giro Afectivo’. This turn, so far, has not dabbled in the social science literature that is written in Spanish. This paper draws on a singular panorama of discussions about contemporary social studies of affect and emotion, and it’s vertebrate by some of its expressions in the contemporary academy.

  7. The Affective Turn

    DEFF Research Database (Denmark)

    Carnera, Alexander

    2012-01-01

    This paper confronts biopolitics with modern labour addressing questions of ‘governmentality’, ‘self-management’ and ‘social innovation’. It argues that the new modes of production within immaterial labour involve a new complex relation between on the one hand the ‘Art of Governance......-management that human individuation ties together modes of productions with affects and emotions. Introducing Spinoza's concept of ‘affect’, and Gilles Deleuze's reading of Spinoza's ethics focusing on the ‘affective turn’ in relation to the new economy and society, the paper argues for a more positive notion of...... biopolitics that surpasses that of governmentality. The affective self-relation is used as a research tool to analyse the creation of social and economic values in our new modes of productions, for instance, within free labour of the cultural industry. The movie The Five Obstructions is used to show how...

  8. Mechanisms underlying the growth inhibitory effects of the cyclo-oxygenase-2 inhibitor celecoxib in human breast cancer cells

    OpenAIRE

    Basu, Gargi D; Pathangey, Latha B; Tinder, Teresa L; Gendler, Sandra J.; Mukherjee, Pinku

    2005-01-01

    Introduction Inhibitors of cyclo-oxygenase (COX)-2 are being extensively studied as anticancer agents. In the present study we evaluated the mechanisms by which a highly selective COX-2 inhibitor, celecoxib, affects tumor growth of two differentially invasive human breast cancer cell lines. Methods MDA-MB-231 (highly invasive) and MDA-MB-468 (moderately invasive) cell lines were treated with varying concentrations of celecoxib in vitro, and the effects of this agent on cell growth and angioge...

  9. A Revisit to the Corrosion Inhibition of Aluminum in Aqueous Alkaline Solutions by Water-Soluble Alginates and Pectates as Anionic Polyelectrolyte Inhibitors

    Directory of Open Access Journals (Sweden)

    Refat Hassan

    2013-01-01

    Full Text Available The corrosion behavior of aluminum (Al in alkaline media in presence of some natural polymer inhibitors has been reinvestigated. The inhibition action of the tested inhibitors was found to obey both Langmuir and Freundlich isotherms models. The inhibition efficiency was found to increase with increasing the inhibitors concentration and decrease with increasing the temperature, suggesting physical adsorption mechanism. Factors such as the concentration and geometrical structure of the inhibitor, concentration of the corrosive medium, and temperature affecting the corrosion rates were examined. The kinetic parameters were evaluated, and a suitable corrosion mechanism consistent with the kinetic results obtained is suggested and discussed.

  10. Use of selective serotonin reuptake inhibitors reduces fertility in men.

    Science.gov (United States)

    Nørr, L; Bennedsen, B; Fedder, J; Larsen, E R

    2016-05-01

    Clinical review of the present data on the effects of selective serotonin reuptake inhibitors (SSRIs) on male fertility was the objective of the study. PubMed and Scopus were searched for publications in English or Danish and reviewed. Human trials, animal studies and in vitro studies were included. Use of SSRIs negatively affects semen parameters in most studies. In some studies, SSRIs are also shown to reduce DNA integrity. SSRIs can also delay ejaculation. Depression and anxiety can cause reduced libido, erectile dysfunction and delayed ejaculation as well. The use of SSRIs seems to reduce male fertility by affecting semen parameters, although most studies have a degree of confounding by indication caused by the underlying depression. PMID:27019308

  11. Proton Pump Inhibitor Use and the Antifracture Efficacy of Alendronate

    DEFF Research Database (Denmark)

    Abrahamsen, Bo; Eiken, Pia Agnete; Eastell, Richard

    2011-01-01

    Background: Proton pump inhibitors (PPIs) are widely used in elderly patients and are frequently coadministered in users of oral bisphosphonates. Biologically, PPIs could affect the absorption of calcium, vitamin B12, and bisphosphonates and could affect the osteoclast proton pump, thus interacting...... no significant impact of concurrent use of histamine H2 receptor blockers. Conclusions: Concurrent PPI use was associated with a dose-dependent loss of protection against hip fracture with alendronate in elderly patients. This is an observational study, so a formal proof of causality cannot be made...... with bisphosphonate antifracture efficacy. Moreover, PPIs themselves have been linked to osteoporotic fractures. Methods: Population-based, national register–based, open cohort study of 38 088 new alendronate sodium users with a mean duration of follow-up of 3.5 years. We related risk of hip fracture...

  12. Toxicity inhibitors protect lipid membranes from disruption by Aβ42.

    Science.gov (United States)

    Malishev, Ravit; Nandi, Sukhendu; Kolusheva, Sofiya; Levi-Kalisman, Yael; Klärner, Frank-Gerrit; Schrader, Thomas; Bitan, Gal; Jelinek, Raz

    2015-11-18

    Although the precise molecular factors linking amyloid β-protein (Aβ) to Alzheimer's disease (AD) have not been deciphered, interaction of Aβ with cellular membranes has an important role in the disease. However, most therapeutic strategies targeting Aβ have focused on interfering with Aβ self-assembly rather than with its membrane interactions. Here, we studied the impact of three toxicity inhibitors on membrane interactions of Aβ42, the longer form of Aβ, which is associated most strongly with AD. The inhibitors included the four-residue C-terminal fragment Aβ(39-42), the polyphenol (-)-epigallocatechin-3-gallate (EGCG), and the lysine-specific molecular tweezer, CLR01, all of which previously were shown to disrupt different steps in Aβ42 self-assembly. Biophysical experiments revealed that incubation of Aβ42 with each of the three modulators affected membrane interactions in a distinct manner. Interestingly, EGCG and CLR01 were found to have significant interaction with membranes themselves. However, membrane bilayer disruption was reduced when the compounds were preincubated with Aβ42, suggesting that binding of the assembly modulators to the peptide attenuated their membrane interactions. Importantly, our study reveals that even though the three tested compounds affect Aβ42 assembly differently, membrane interactions were significantly inhibited upon incubation of each compound with Aβ42, suggesting that preventing the interaction of Aβ42 with the membrane contributes substantially to inhibition of its toxicity by each compound. The data suggest that interference with membrane interactions is an important factor for Aβ42 toxicity inhibitors and should be taken into account in potential therapeutic strategies, in addition to disruption or remodeling of amyloid assembly. PMID:26317327

  13. Inhibiting properties and adsorption of an amine based fatty acid corrosion inhibitor on carbon steel in aqueous carbon dioxide solutions

    Energy Technology Data Exchange (ETDEWEB)

    Buchweishaija, Joseph

    1997-12-31

    Carbon dioxide corrosion is a major corrosion problem in oil and gas production systems and many organic inhibitors have been tested and used to protect the substrate from corrosion. This thesis studies the mechanism of interaction of the inhibitor molecule with the metallic substrate and how this affects the dissolution rate of the metal. The performance of a commercial amine based fatty acid corrosion inhibitor has been investigated using rotating cylinder electrodes and carbon steel electrodes in CO{sub 2} saturated formation water in the temperature range between 35 to 80{sup o}C. The corrosion process was monitored by electrochemical impedance measurements, and at the end of each experiment full polarization curves were recorded. When the inhibitor was applied on noncorroded electrodes, high inhibitor performance, over 99.7%, was observed independent of temperature. On precorroded electrodes inhibitor performance was found to depend on temperature and time of precorrosion. Above 60{sup o}C, the inhibitor performance decreased with increasing time of precorrosion, presumably because of the formation of a corrosion film of either iron carbonate or a combination of iron carbonate and iron carbide which prevent the inhibitor from reaching the surface. The inhibitor protection efficiency was assumed to be associated with the degree of inhibitor coverage at the material surface, and adsorption isotherms have been calculated in the concentration range between 0.1 ppm and 100 ppm. A Langmuir isotherm was found to give the best fit. The inhibitor performance on a 2 days precorroded rotating electrode was investigated at different solution pH ranging between 4.5 and 6.5 at 35{sup o}C. 130 refs., 80 figs., 22 tabs.

  14. XIMELAGATRAN: A NEW DIRECT THROMBIN INHIBITOR

    Directory of Open Access Journals (Sweden)

    Mehta Hiren R

    2011-04-01

    Full Text Available Venous thromboembolism is a serious illness that affects patient morbidity and mortality and presents a significant management challenge to healthcare providers world-wide. Despite major achievements in the significant reduction of thromboembolic complications, the most common therapies currently used for prevention and treatment of venous thromboembolism – heparins and vitamin K antagonists such as warfarin – have several limitations. Warfarin sodium is an effective oral anticoagulant drug. However, warfarin has a narrow therapeutic window with significant risks of hemorrhage at therapeutic concentrations. Dosing is difficult and requires frequent monitoring. New oral anticoagulant agents are required to improve current anticoagulant therapy. Furthermore, while warfarin is effective in venous disease, it does not provide more than 60% risk reduction compared with placebo in venous thrombosis prophylaxis and considerably lower risk reduction in terms of arterial thrombosis. Unlike warfarin and heparin, these direct thrombin inhibitors are able to inhibit fibrin-bound thrombin and so produce more effective inhibition of coagulation. Importantly, some members of this class of drugs have been developed for oral administration. Ximelagatran is an oral pro-drug of melagatran, a synthetic small peptidomimetic with direct thrombin inhibitory actions and anticoagulant activity. As an oral agent, ximelagatran has a number of desirable properties including a rapid onset of action, fixed dosing, stable absorption, apparent low potential for medication interactions, and no requirement for monitoring of drug levels or dose adjustment. It has a short plasma elimination half-life of about 4 hours in cases of unexpected hemorrhage or need for reversal.

  15. Affected in the nightclub

    DEFF Research Database (Denmark)

    Demant, Jakob Johan

    2013-01-01

    experiences within a club as a way of understanding the complexities of pleasure. The study does so by addressing experiences through the concept of affects, which is situated within a framework of a non-representational theory of space. Anxiety, pride, anger, shame and embarrassment are embodied...

  16. Nitrification Inhibitors: A Perspective Tool to Mitigate Greenhouse Gas Emissions from Rice Soils

    Directory of Open Access Journals (Sweden)

    Sandeep K. Malyan

    2016-08-01

    Full Text Available Rice fields are significant contributors of greenhouse gases mainly methane and nitrous oxide to the atmosphere. Increasing concentrations of these greenhouse gases play significant role in changing atmospheric chemistry such as mean air temperature, rainfall pattern, drought, and flood frequency. Mitigation of greenhouse gases for achieving sustainable agriculture without affecting economical production is one the biggest challenge of twenty first century at national and global scale. On the basis of published scientific studies, we hereby assess the use of nitrification inhibitors for greenhouse gas mitigation from rice soil. Biologically oxidation of ammonium to nitrate is termed as nitrification and materials which suppress this process are known as nitrification inhibitors. Soil amendment by addition of certain nitrification inhibitors such as neem oil coated urea, nimin-coated urea; dicyandiamide, encapsulated calcium carbide, and hydroquinone reduce cumulative methane and nitrous oxide emission from rice. Firstly, these inhibitors reduce nitrous oxide emissions both directly by nitrification (by reducing NH4+ to NO3- as well as indirectly by de-nitrification (by reducing NO3- availability in soil. Secondly, methane emission from rice soil can be reduced by enhancing methane oxidation and suppressing methane production and further by reducing the aerenchymal transportation through rice plant. Application of some of the nitrification inhibitors such as calcium carbide and encapsulated calcium carbide reduce methane production by releasing acetylene gas which helps in reducing the population of methanogenic microbes in the soil. Application of nitrification inhibitors also helps to maintain soil redox potential at higher level subsequently reducing cumulative methane emission from soil. Plant derived organic nitrification inhibitors (neem oil, neem cake, karanja seed extract are eco-friendly and possess substantial greenhouse gas mitigation

  17. A novel strategy for the treatment of diabetes mellitus - sodium glucose co-transport inhibitors

    Directory of Open Access Journals (Sweden)

    Asfandyar Khan Niazi

    2010-12-01

    Full Text Available Background: Diabetes is one of the most common chronic diseases, affecting almost 3 million in Canada alone and is characterized by increased blood glucose levels. Treatment varies from lifestyle changes to oral anti-diabetics and/or insulin. Sodium glucose co-transport inhibitors may offer promising treatment for patients suffering from diabetes. The inhibitors act by increasing the loss of glucose in urine by decreasing the reabsorption of glucose from the proximal tubules of nephrons. Aims: The aim of this review was to assess the efficacy of sodium glucose co-transport inhibitors in the treatment of diabetes as well as any adverse effects. Materials and Methods: Databases such as MEDLINE, COCHRANE and EMBASE were systematically searched for literature on the efficacy of sodium glucose co-transport inhibitors in improving the glycemic control of patients with diabetes. Results: Research showed that sodium glucose co-transport inhibitors significantly decreased blood glucose levels by increasing glucosuria. Due to the diuretic effects of these inhibitors, diabetic patients who were suffering from hypertension showed a decrease in blood pressure. The caloric loss associated with these inhibitors resulted in weight loss as well. The most common adverse effect seen in patients on these medications was mycotic infection of the urinary or genital tract. Conclusion: Sodium glucose co-transport inhibitors may be an effective line of treatment for diabetes. Although short-term research has shown these drugs to be safe and well-tolerated, studies should be conducted to assess the long-term effects of these drugs.

  18. A novel strategy for the treatment of diabetes mellitus - sodium glucose co-transport inhibitors

    Directory of Open Access Journals (Sweden)

    Asfandyar Khan Niazi

    2010-01-01

    Full Text Available Background: Diabetes is one of the most common chronic diseases, affecting almost 3 million in Canada alone and is characterized by increased blood glucose levels. Treatment varies from lifestyle changes to oral anti-diabetics and/or insulin. Sodium glucose co-transport inhibitors may offer promising treatment for patients suffering from diabetes. The inhibitors act by increasing the loss of glucose in urine by decreasing the reabsorption of glucose from the proximal tubules of nephrons. Aims: The aim of this review was to assess the efficacy of sodium glucose co-transport inhibitors in the treatment of diabetes as well as any adverse effects. Materials and Methods : Databases such as MEDLINE, COCHRANE and EMBASE were systematically searched for literature on the efficacy of sodium glucose co-transport inhibitors in improving the glycemic control of patients with diabetes. Results: Research showed that sodium glucose co-transport inhibitors significantly decreased blood glucose levels by increasing glucosuria. Due to the diuretic effects of these inhibitors, diabetic patients who were suffering from hypertension showed a decrease in blood pressure. The caloric loss associated with these inhibitors resulted in weight loss as well. The most common adverse effect seen in patients on these medications was mycotic infection of the urinary or genital tract. Conclusion: Sodium glucose co-transport inhibitors may be an effective line of treatment for diabetes. Although short-term research has shown these drugs to be safe and well-tolerated, studies should be conducted to assess the long-term effects of these drugs.

  19. VEGF Inhibitors for Cancer Therapy

    Directory of Open Access Journals (Sweden)

    Prakash S. Sukhramani

    2010-01-01

    Full Text Available Despite significant advances in systemic therapies, radiation oncology, and surgical techniques, many patients with cancer are still incurable. A novel therapeutic approach has been to target the vascular endothelial growth factors (VEGFs which are often mutated and/or over-expressed in many tumors. The ligands and receptors of VEGF family are well established as key regulators of angiogenesis and vasculogenesis processes. VEGF is a homodimeric, basic, 45 kDa glycoprotein specific for vascular endothelial cells. Specifically, VEGF participates in regulation of the female reproductive cycle, wound healing, inflammation, vascular permeability, vascular tone, hematopoiesis and also contributes to pathological angiogenesis disorders such as cancer, rheumatoid arthritis, diabetic retinopathy and the neovascular form of macular degeneration. Thus, the role of VEGF has been extensively studied in the pathogenesis and angiogenesis of human cancers. Clinical trials have anti-VEGF therapies are effective in reducing tumor size, metastasis and blood vessel formation. Clinically, this may result in increased progression free survival, overall patient survival rate and will expand the potential for combinatorial therapies. The aim of present review is on the cellular responses of VEGF inhibitors and their implications for cancer therapy.

  20. ALK inhibitors, a pharmaceutical perspective

    Directory of Open Access Journals (Sweden)

    Arturo eGalvani

    2012-02-01

    Full Text Available In 2007, the ALK tyrosine kinase, already known to be translocated and activated in Anaplastic Large Cell Lymphoma, and a few other rare cancers, was described as a potential therapeutic target for a subset of non small-cell lung cancer (NSCLC patients. Clinical proof of concept, culminating in the recent approval by the FDA of the Pfizer drug Xalkori (crizotinib, formerly known as PF-02341066 followed in record time. The drug was approved together with a companion diagnostic, the Vysis ALK Break Apart FISH Probe Kit (Abbott Molecular, Inc. for detection of eligible patients. This remarkable example of the coming of age of personalized medicine in cancer therapy is hopefully only an auspice of things to come in this rapidly developing field. Perhaps unsurprisingly, however, the appearance of clinical acquired resistance to crizotinib has already been observed early on in clinical testing, with the identification of several ALK secondary point mutations which diminish drug efficacy, and which open the way for development of second-generation inhibitors. It is also emerging that acquired resistance to crizotinib may also occur through ALK-independent mechanisms, which still need to be elucidated in detail.

  1. Vascular calcification: Inducers and inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Donghyun, E-mail: dhlee@cau.ac.kr [Department of Biomedical Engineering, Division of Integrative Engineering, Chung-Ang University, 221 Heukseok-Dong, Dongjak-Gu, Seoul 156-756 (Korea, Republic of)

    2011-09-15

    Highlights: {center_dot} Types of vascular calcification processes. {center_dot} Inducers of vascular calcification. {center_dot} Inhibitors of vascular calcifications. {center_dot} Clinical utility for vascular calcification therapy. {center_dot} Implications for the development of new tissue engineering strategies. - Abstract: Unlike the traditional beliefs, there are mounting evidences suggesting that ectopic mineral depositions, including vascular calcification are mostly active processes, many times resembling that of the bone mineralization. Numbers of agents are involved in the differentiation of certain subpopulation of smooth muscle cells (SMCs) into the osteoblast-like entity, and the activation and initiation of extracellular matrix ossification process. On the other hand, there are factors as well, that prevent such differentiation and ectopic calcium phosphate formation. In normal physiological environments, activities of such procalcific and anticalcific regulatory factors are in harmony, prohibiting abnormal calcification from occurring. However, in certain pathophysiological conditions, such as atherosclerosis, chronic kidney disease (CKD), and diabetes, such balances are altered, resulting in abnormal ectopic mineral deposition. Understanding the factors that regulate the formation and inhibition of ectopic mineral formation would be beneficial in the development of tissue engineering strategies for prevention and/or treatment of such soft-tissue calcification. Current review focuses on the factors that seem to be clinically relevant and/or could be useful in developing future tissue regeneration strategies. Clinical utilities and implications of such factors are also discussed.

  2. Allosteric small-molecule kinase inhibitors

    DEFF Research Database (Denmark)

    Wu, Peng; Clausen, Mads Hartvig; Nielsen, Thomas E.

    2015-01-01

    Small-molecule kinase inhibitors are invaluable targeted therapeutics for the treatment of various human diseases, especially cancers. While the majority of approved and developed preclinical small-molecule inhibitors are characterized as type I or type II inhibitors that target the ATP......-binding pocket of kinases, the remarkable sequential and structural similarity among ATP pockets renders the selective inhibition of kinases a daunting challenge. Therefore, targeting allosteric pockets of kinases outside the highly conversed ATP pocket has been proposed as a promising alternative to overcome...

  3. An Updated Review of Tyrosinase Inhibitors

    Directory of Open Access Journals (Sweden)

    Te-Sheng Chang

    2009-05-01

    Full Text Available Tyrosinase is a multifunctional, glycosylated, and copper-containing oxidase, which catalyzes the first two steps in mammalian melanogenesis and is responsible for enzymatic browning reactions in damaged fruits during post-harvest handling and processing. Neither hyperpigmentation in human skin nor enzymatic browning in fruits are desirable. These phenomena have encouraged researchers to seek new potent tyrosinase inhibitors for use in foods and cosmetics. This article surveys tyrosinase inhibitors newly discovered from natural and synthetic sources. The inhibitory strength is compared with that of a standard inhibitor, kojic acid, and their inhibitory mechanisms are discussed.

  4. PENGHAMBAT α AMILASE: JENIS, SUMBER, DAN POTENSI PEMANFAATANNYA DALAM KESEHATAN [α Amylase Inhibitors: Types, Sources, and Their Potential Utilization for Health Purposes

    Directory of Open Access Journals (Sweden)

    Budiasih Wahyuntari

    2011-12-01

    Full Text Available SUMMARYAlpha amylase inhibitors affect carbohydrate metabolism in digestive system. The inhibitors induce carbohydrate tolerance, fullness and prolonging gastric emptying that might be used to aid in diabetic and obesity treatment. There are two types of α- amylase inhibitors, proteinaceous and non-proteinaceous ones. Proteinaceous inhibitor is classified into seven classes including legumes, lectin, knottin, cereal, Kunitz, -thionin and thaumatin types. Plant proteinaceous inhibitors are present in cereals and legumes. Some non-proteinaceous inhibitors include flavonid, polyphenols, organic acid that might be produced by microbes or extracted from plants such as acarbose, saponin dan cardiac glycoside, gallic acid, proto-catechuic acid, caffeic acid, ellagic acid, ferulic acid, quercetin hibiscus acid and α-, β- and γ-cyclodextrin.

  5. Neurotransmitters affecting time perception

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    BACKGROUND:It has been demonstrated that dopamine and acetylcholine are the main neurotransmitters that affect time perception,which is also affected by other neurotransmitters.OBJECTIVE:To summarize how the neurotransmitter affect the time perception,and put forward the perspectives for further study on time perception.RETRIEVE STRATEGY:An online search for related literatures published in English was conducted in Elsevier SDOL(ScienceDirect Online)database from May 1990 to March 2007 using key words of "timing neurotransmitter".Totally 69 literatures were collected,and they were primarily checked.Inclusive criteria:Reviews and experimental studies;correlative studies of timing neurotransmitter.Exclusive criteria:Repeated studies.LITERATURE EVALUATION:The literatures were mainly sourced from Cognitive Brain Research and Neuroscience,and they were analyzed according to the inclusive criteria.Nineteen of them were involved,and all were experimental studies and reviews.DATA SYNTHESIS:The studies on time perception are developed mainly concentrating on dopamine and acetylcholine.Dopamine D2 receptors mainly affect the speed of internal clock.Dopamine receptors play an important role in both timing excitation and inhibition,which suggests the bi-directional regulation of dopamine.Injection of dopamine agonist can affect the attention to timing information.Injection of BW813U(antagonist of acetylcholine) can induce memory disorder,which indicates the effect of acetylcholine on timing memory,and further study shows that it is the effect of acetylcholine in precentral medial area.In a word,the study on the neurotransmitters affecting time perception is still at the primary stage.CONCLUSION:Dopamine and acetylcholine are the neurotransmitters known to be related to time perception.Dopamine in the basal ganglia is related to internal-clock in the range of seconds and minutes;Acetylcholine in prefrontal cortex is related to the mechanisms of temporal memory and attention

  6. Thioester derivatives of the natural product psammaplin A as potent histone deacetylase inhibitors

    Directory of Open Access Journals (Sweden)

    Matthias G. J. Baud

    2013-01-01

    Full Text Available There has been significant interest in the bioactivity of the natural product psammaplin A, most recently as a potent and isoform selective HDAC inhibitor. Here we report our preliminary studies on thioester HDAC inhibitors derived from the active monomeric (thiol form of psammaplin A, as a means to improve compound delivery into cells. We have discovered that such compounds exhibit both potent cytotoxicity and enzymatic inhibitory activity against recombinant HDAC1. The latter effect is surprising since previous SAR suggested that modification of the thiol functionality should detrimentally affect HDAC potency. We therefore also report our preliminary studies on the mechanism of action of this observed effect.

  7. Affects and assemblages

    DEFF Research Database (Denmark)

    Samson, Kristine

    happens to aesthetics and how does it change the existing social and geographical understanding of urban space? The paper sets out to reintroduce aesthetical aspects of affects and assemblages in relation to urban space and urban planning. It presupposes urban space as a continuous state of becoming where...... ‘throwntogetherness’ (Massey 2005) or assemblage (Farias & Bender 2010) of perspectives bridging for instance the social and cultural experienced space investigated by the geographer and urban sociologist with the material and formal aesthetics of the architect and urban planner....... cultural geopgraphy. On this backdrop the paper states that affects and assemblages could serve as key notions for the reassembling the aesthetics of urban space. Thus, the paper suggest a less formal understanding of urban space and aesthetics, proposing an understanding of aesthetics as a...

  8. Comfortable bodies: sedentary affects

    OpenAIRE

    David Bissell

    2008-01-01

    Whilst to be comfortable is often equated with conservatism and complacency, this paper considers the various and often complex configurations of comfort as a desirable corporeal sensibility. Subsequently, this paper considers what corporeal comfort as an affective sensibility is and can do to theorisations of the sedentary body. The sensibility of corporeal comfort induced through the relationality between bodies and proximate objects is explored to trace through some of the affectual circul...

  9. Cytoplasm Affects Embryonic Development

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    @@ Recent studies by CAS researchers furnish strong evidence that a fertilized egg's nucleus isn't the sole site of control for an embryo's development. A research team headed by Prof. Zhu Zuoyan from the CAS Institute of Hydrobiology in Wuhan discovered that cytoplasm affects the number of vertebrae in cloned offspring created when nuclei from one fish genus were transplanted to enucleated eggs of another.

  10. Factors Affecting Wound Healing

    OpenAIRE

    Guo, S; DiPietro, L. A.

    2010-01-01

    Wound healing, as a normal biological process in the human body, is achieved through four precisely and highly programmed phases: hemostasis, inflammation, proliferation, and remodeling. For a wound to heal successfully, all four phases must occur in the proper sequence and time frame. Many factors can interfere with one or more phases of this process, thus causing improper or impaired wound healing. This article reviews the recent literature on the most significant factors that affect cutane...

  11. Influenza neuraminidase inhibitors: antiviral action and mechanisms of resistance

    Science.gov (United States)

    McKimm‐Breschkin, Jennifer L.

    2012-01-01

    Please cite this paper as: McKimm‐Breschkin (2012) Influenza neuraminidase inhibitors: Antiviral action and mechanisms of resistance. Influenza and Other Respiratory Viruses 7(Suppl. 1), 25–36. There are two major classes of antivirals available for the treatment and prevention of influenza, the M2 inhibitors and the neuraminidase inhibitors (NAIs). The M2 inhibitors are cheap, but they are only effective against influenza A viruses, and resistance arises rapidly. The current influenza A H3N2 and pandemic A(H1N1)pdm09 viruses are already resistant to the M2 inhibitors as are many H5N1 viruses. There are four NAIs licensed in some parts of the world, zanamivir, oseltamivir, peramivir, and a long‐acting NAI, laninamivir. This review focuses on resistance to the NAIs. Because of differences in their chemistry and subtle differences in NA structures, resistance can be both NAI‐ and subtype specific. This results in different drug resistance profiles, for example, the H274Y mutation confers resistance to oseltamivir and peramivir, but not to zanamivir, and only in N1 NAs. Mutations at E119, D198, I222, R292, and N294 can also reduce NAI sensitivity. In the winter of 2007–2008, an oseltamivir‐resistant seasonal influenza A(H1N1) strain with an H274Y mutation emerged in the northern hemisphere and spread rapidly around the world. In contrast to earlier evidence of such resistant viruses being unfit, this mutant virus remained fully transmissible and pathogenic and became the major seasonal A(H1N1) virus globally within a year. This resistant A(H1N1) virus was displaced by the sensitive A(H1N1)pdm09 virus. Approximately 0·5–1·0% of community A(H1N1)pdm09 isolates are currently resistant to oseltamivir. It is now apparent that variation in non‐active site amino acids can affect the fitness of the enzyme and compensate for mutations that confer high‐level oseltamivir resistance resulting in minimal impact on enzyme function. PMID:23279894

  12. Affective Image Colorization

    Institute of Scientific and Technical Information of China (English)

    Xiao-Hui Wang; Jia Jia; Han-Yu Liao; Lian-Hong Cai

    2012-01-01

    Colorization of gray-scale images has attracted many attentions for a long time.An important role of image color is the conveyer of emotions (through color themes).The colorization with an undesired color theme is less useful,even it is semantically correct.However this has been rarely considered.Automatic colorization respecting both the semantics and the emotions is undoubtedly a challenge.In this paper,we propose a complete system for affective image colorization.We only need the user to assist object segmentation along with text labels and an affective word.First,the text labels along with other object characters are jointly used to filter the internet images to give each object a set of semantically correct reference images.Second,we select a set of color themes according to the affective word based on art theories.With these themes,a generic algorithm is used to select the best reference for each object,balancing various requirements.Finally,we propose a hybrid texture synthesis approach for colorization.To the best of our knowledge,it is the first system which is able to efficiently colorize a gray-scale image semantically by an emotionally controllable fashion.Our experiments show the effectiveness of our system,especially the benefit compared with the previous Markov random field (MRF) based method.

  13. Inhibitors of alanine racemase enzyme: a review.

    Science.gov (United States)

    Azam, Mohammed Afzal; Jayaram, Unni

    2016-08-01

    Alanine racemase is a fold type III PLP-dependent amino acid racemase enzyme catalysing the conversion of l-alanine to d-alanine utilised by bacterial cell wall for peptidoglycan synthesis. As there are no known homologs in humans, it is considered as an excellent antibacterial drug target. The standard inhibitors of this enzyme include O-carbamyl-d-serine, d-cycloserine, chlorovinyl glycine, alaphosphin, etc. d-Cycloserine is indicated for pulmonary and extra pulmonary tuberculosis but therapeutic use of drug is limited due to its severe toxic effects. Toxic effects due to off-target affinities of cycloserine and other substrate analogs have prompted new research efforts to identify alanine racemase inhibitors that are not substrate analogs. In this review, an updated status of known inhibitors of alanine racemase enzyme has been provided which will serve as a rich source of structural information and will be helpful in generating selective and potent inhibitor of alanine racemase. PMID:26024289

  14. Strategies for discontinuation of proton pump inhibitors

    DEFF Research Database (Denmark)

    Haastrup, Peter; Paulsen, Maja S; Begtrup, Luise M;

    2014-01-01

    PURPOSE: Proton pump inhibitors (PPIs) are considered to be overprescribed. Consensus on how to attempt discontinuation is, however, lacking. We therefore conducted a systematic review of clinical studies on discontinuation of PPIs. METHODS: Systematic review based on clinical studies investigating...

  15. Cyanobacterial secondary metabolites as acetylcholinesterase inhibitors

    Czech Academy of Sciences Publication Activity Database

    Zelík, Petr; Masojídek, Jiří; Štys, Dalibor; Kopecký, Jiří

    Kunming : Verlag, 2006, s. 52-53. [International Conference on Applied Phycology /10./. Kunming (CN), 24.07.2005-28.07.2005] Institutional research plan: CEZ:AV0Z50200510 Keywords : cyanobacteria * acetylcholinesterase inhibitors Subject RIV: EE - Microbiology, Virology

  16. Progress and prospects on DENV protease inhibitors.

    Science.gov (United States)

    Timiri, Ajay Kumar; Sinha, Barij Nayan; Jayaprakash, Venkatesan

    2016-07-19

    New treatments are desperately required to combat increasing rate of dengue fever cases reported in tropical and sub-tropical parts of the world. Among the ten proteins (structural and non-structural) encoded by dengue viral genome, NS2B-NS3 protease is an ideal target for drug discovery. It is responsible for the processing of poly protein that is required for genome replication of the virus. Moreover, inhibitors designed against proteases were found successful in Human Immuno-deficiency Virus (HIV) and Hepatitis C Virus (HCV). Complete molecular mechanism and a survey of inhibitors reported against dengue protease will be helpful in designing effective and potent inhibitors. This review provides an insight on molecular mechanism of dengue virus protease and covers up-to-date information on different inhibitors reported against dengue proteases with medicinal chemistry perspective. PMID:27092412

  17. Effects of multiphase flow on corrosion inhibitor

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Y.; Jepson, W.P. [Ohio Univ., Athens, OH (United States); Chen, H.J. [Chevron Petroleum Technology Co., La Habra, CA (United States)

    1999-11-01

    This paper investigates the inhibition performance of a typical imidazoline based inhibitor under multiphase flow. Electrochemical impedance spectroscopy (EIS) measurements were carried out in a 101.6 mm I.D., 15 m long acrylic flow loop using ASTM substitute saltwater and carbon dioxide gas. This flow loop system can generate slug flow, fill pipe flow and other multiphase flow patterns. Effects of different flow conditions on inhibition performance of this typical inhibitor were examined. The system was maintained at a pressure of 0.136 MPa and a temperature of 40 C. EIS measurements for this inhibitor in a Rotating Cylinder Electrode (RCE) system were also conducted. Different equivalent circuit models were used to fit the experiment data for both the RCE and flow loop systems. The high shear stress and turbulence due to the mixing vortex and the bubble impact in multiphase flow can enhance the corrosion or reduce the inhibition performance of inhibitors.

  18. Inhibitors of Acetylcholinesterase and Butyrylcholinesterase Meet Immunity

    Directory of Open Access Journals (Sweden)

    Miroslav Pohanka

    2014-06-01

    Full Text Available Acetylcholinesterase (AChE inhibitors are widely used for the symptomatic treatment of Alzheimer’s disease and other dementias. More recent use is for myasthenia gravis. Many of these inhibitors interact with the second known cholinesterase, butyrylcholinesterase (BChE. Further, evidence shows that acetylcholine plays a role in suppression of cytokine release through a “cholinergic anti-inflammatory pathway” which raises questions about the role of these inhibitors in the immune system. This review covers research and discussion of the role of the inhibitors in modulating the immune response using as examples the commonly available drugs, donepezil, galantamine, huperzine, neostigmine and pyridostigmine. Major attention is given to the cholinergic anti-inflammatory pathway, a well-described link between the central nervous system and terminal effector cells in the immune system.

  19. Inhibitors of acetylcholinesterase and butyrylcholinesterase meet immunity.

    Science.gov (United States)

    Pohanka, Miroslav

    2014-01-01

    Acetylcholinesterase (AChE) inhibitors are widely used for the symptomatic treatment of Alzheimer's disease and other dementias. More recent use is for myasthenia gravis. Many of these inhibitors interact with the second known cholinesterase, butyrylcholinesterase (BChE). Further, evidence shows that acetylcholine plays a role in suppression of cytokine release through a "cholinergic anti-inflammatory pathway" which raises questions about the role of these inhibitors in the immune system. This review covers research and discussion of the role of the inhibitors in modulating the immune response using as examples the commonly available drugs, donepezil, galantamine, huperzine, neostigmine and pyridostigmine. Major attention is given to the cholinergic anti-inflammatory pathway, a well-described link between the central nervous system and terminal effector cells in the immune system. PMID:24893223

  20. Pharmacophore Identification of Hydroxamate HDAC 1 Inhibitors

    Institute of Scientific and Technical Information of China (English)

    YU,Liqin; LIU,Fei; CHEN,Yadong; YOU,Qidong

    2009-01-01

    A three-dimensional pharmacophore model was established based on 24 hydroxamate histone deacetylase(HDAC)inhibitors by HypoGen algorithm embedded in Catalyst software.The best pharmacophore hypothesis(Hypol),consisting of four chemical features(one hydrogen-bond acceptor,one aromatic ring and two hydrophobicgroups).has a correlation coefficient of 0.946.The Hypol Was also validated by a test set consisting of 20 othercompounds.Compared with the prior studies towards HDAC inhibitors the detailed chemical features of the"CAP"region in the reported HDAC inhibitors were for the first time depicted,which would be helpful in the further de-signing of novel HDAC inhibitors.

  1. Kinase inhibitors for advanced medullary thyroid carcinoma

    Directory of Open Access Journals (Sweden)

    Martin Schlumberger

    2012-01-01

    Full Text Available The recent availability of molecular targeted therapies leads to a reconsideration of the treatment strategy for patients with distant metastases from medullary thyroid carcinoma. In patients with progressive disease, treatment with kinase inhibitors should be offered.

  2. Lipoxygenase inhibitors derived from marine macroalgae.

    Science.gov (United States)

    Kurihara, Hideyuki; Kagawa, Yoshio; Konno, Remi; Kim, Sang Moo; Takahashi, Koretaro

    2014-03-01

    The solvent extracts from the algae Sargassum thunbergii (Sargassaceae) and Odonthalia corymbifera (Rhodomelaceae) were subjected to soybean lipoxygenase inhibitory screening. Two hydrophobic inhibitors were obtained from the extracts of S. thunbergii through inhibitory assay-guided fractionation. The inhibitors were identified as known exo-methylenic alkapolyenes (6Z,9Z,12Z,15Z)-1,6,9,12,15-henicosapentaene (1) and (6Z,9Z,12Z,15Z,18Z)-1,6,9,12,15,18-henicosahexaene (2). The alkapolyenes 1 and 2 showed higher inhibitory activity than the known inhibitor nordihydroguaiaretic acid (NDGA). Pheophytin a (3) was obtained from the extract of O. corymbifera. The inhibitor 3 also showed higher inhibitory activity than NDGA. This is the first report on lipoxygenase inhibition of exo-methylenic alkapolyenes and a chlorophyll a-related substance. PMID:24495846

  3. Whole-exome sequencing to identify genetic risk variants underlying inhibitor development in severe hemophilia A patients.

    Science.gov (United States)

    Gorski, Marcin M; Blighe, Kevin; Lotta, Luca A; Pappalardo, Emanuela; Garagiola, Isabella; Mancini, Ilaria; Mancuso, Maria Elisa; Fasulo, Maria Rosaria; Santagostino, Elena; Peyvandi, Flora

    2016-06-01

    The development of neutralizing antibodies (inhibitors) against coagulation factor VIII (FVIII) is the most problematic and costly complication of FVIII replacement therapy that affects up to 30% of previously untreated patients with severe hemophilia A. The development of inhibitors is a multifactorial complication involving environmental and genetic factors. Among the latter, F8 gene mutations, ethnicity, family history of inhibitors, and polymorphisms affecting genes involved in the immune response have been previously investigated. To identify novel genetic elements underling the risk of inhibitor development in patients with severe hemophilia A, we applied whole-exome sequencing (WES) and data analysis in a selected group of 26 Italian patients with (n = 17) and without (n = 9) inhibitors. WES revealed several rare, damaging variants in immunoregulatory genes as novel candidate mutations. A case-control association analysis using Cochran-Armitage and Fisher's exact statistical tests identified 1364 statistically significant variants. Hierarchical clustering of these genetic variants showed 2 distinct patterns of homozygous variants with a protective or harmful role in inhibitor development. When looking solely at coding variants, a total of 28 nonsynonymous variants were identified and replicated in 53 inhibitor-positive and 174 inhibitor-negative Italian severe hemophilia A patients using a TaqMan genotyping assay. The genotyping results revealed 10 variants showing estimated odds ratios in the same direction as in the discovery phase and confirmed the association of the rs3754689 missense variant (OR 0.58; 95% CI 0.36-0.94; P = .028) in a highly conserved haplotype region surrounding the LCT locus on chromosome 2q21 with inhibitor development. PMID:27060170

  4. The Broad Stroke of Hsp90 Inhibitors: Painting over the RAF Inhibitor Paradox.

    Science.gov (United States)

    Vido, Michael J; Aplin, Andrew E

    2015-10-01

    The novel Hsp90 inhibitor XL888 is undergoing clinical investigation for use in conjunction with the rapidly accelerated fibrosarcoma (RAF) kinase inhibitor vemurafenib to treat unresectable melanoma. The addition of XL888 to current regimens may serve an additional purpose by blocking the RAF inhibitor paradox. Such activity could reduce adverse events in patients and provide a biomarker for the successful inhibition of Hsp90 target proteins. PMID:26358385

  5. JAK2 inhibitors: are they the solution?

    OpenAIRE

    Santos, Fabio P S; Verstovsek, Srdan

    2011-01-01

    The discovery of the JAK2V617F mutation in patients with Philadelphia-negative myeloproliferative neoplasms (Ph-negative MPNs) started the era of targeted therapy for these diseases. Until now, patients had few treatment options available, usually restricted to hydroxyurea, interferon preparations, and chemotherapy in more aggressive cases. JAK2 inhibitors have been developed over the past 5 years, and the results of the first clinical trials with JAK2 inhibitors for patients with myelofibros...

  6. Current use of phosphodiesterase inhibitors in urology

    OpenAIRE

    Hakky, Tariq Said; Jain, Lakshay

    2015-01-01

    The causes of male erectile dysfunction (ED) are quite variable and are now commonly divided into etiologies such as ischemia, smooth muscle damage, or altered blood flow. Although varying rates of ED have been reported in literature, the number of men with ED is projected to increase worldwide by 2025 to approximately 322 million. Since the introduction of phosphodiesterase 5 (PDE5) inhibitors, there has been a paradigm shift in the treatment of ED because PDE5 inhibitors address a broad spe...

  7. Update on TNF Inhibitors in Dermatology.

    Science.gov (United States)

    Sobell, Jeffrey M

    2016-06-01

    Emerging data describe new potential indications for tumor necrosis factor (TNF) inhibitors in dermatology, including pediatric psoriasis and hidradenitis suppurativa. New biosimilar TNF agents are in late stages of development and may be available in the United States in the near future. Biosimilar agents are similar but not identical to available TNF inhibitors, and approval requires extensive analytic, toxicity, pharmacokinetic, pharmacodynamic, and clinical testing. Semin Cutan Med Surg 35(supp6):S104-S106. PMID:27537073

  8. Acquired Factor V Inhibitor: A Case Report

    OpenAIRE

    Gaćina, Petar; Kušec, Rajko; Čaržavec, Dubravka; Raić, Biserka; Stančić, Vladimir

    2006-01-01

    A 19-year-old asymptomatic man who was admitted to our hospital for investigation of prolonged screening coagulation assays, prothrombin time and activated partial thromboplastin time is presented. Further evaluation revealed factor V deficiency and the presence of specific factor V inhibitors. The appearance of these inhibitors may be associated with administration of some antibiotics, topical bovine thrombin preparations containing bovine factor V during surgical or dental procedures, after...

  9. Novel hemagglutinin-based influenza virus inhibitors

    OpenAIRE

    Shen, Xintian; Zhang, Xuanxuan; Liu, Shuwen

    2013-01-01

    Influenza virus has caused seasonal epidemics and worldwide pandemics, which caused tremendous loss of human lives and socioeconomics. Nowadays, only two classes of anti-influenza drugs, M2 ion channel inhibitors and neuraminidase inhibitors respectively, are used for prophylaxis and treatment of influenza virus infection. Unfortunately, influenza virus strains resistant to one or all of those drugs emerge frequently. Hemagglutinin (HA), the glycoprotein in influenza virus envelope, plays a c...

  10. Proton pump inhibitors decrease melanogenesis in melanocytes

    OpenAIRE

    Baek, Seung-Hwa; Lee, Sang-Han

    2015-01-01

    Proton pump inhibitors (PPIs) are widely used as inhibitors of gastric juice secretion for treatment of gastroesophageal reflux disease. However, there are no previous studies of the effects on melanogenesis resulting from PPI treatments. Therefore, the aim of the present study was to investigate the effects of PPIs on melanogenesis in melan-a cells derived from immortalized mouse melanocytes. Tyrosinase activity and copper-chelating activity were measured spectrophotometrically. In addition,...

  11. Endogenous angiogenesis inhibitors and their therapeutic implications.

    Science.gov (United States)

    Cao, Y

    2001-04-01

    A number of endogenous inhibitors targeting the tumor vasculature have recently been identified using in vitro and in vivo antiangiogenesis models. While many of these angiogenesis inhibitors display a broad spectrum of biological actions on several systems in the body, several inhibitors including angiostatin, endostatin, and serpin antithrombin seem to act specifically on the proliferating endothelial cell compartment of the newly formed blood vessels. The discovery of these specific endothelial inhibitors not only increases our understanding of the functions of these molecules in the regulation of physiological and pathological angiogenesis, but may also provide an important therapeutic strategy for the treatment of cancer and other angiogenesis dependent diseases, including diabetic retinopathy and chronic inflammations. Systemic administration of these angiogenesis inhibitors in animals significantly suppresses the growth of a variety of tumors and their metastases. However, their production as functional recombinant proteins has been proven to be difficult. In addition, high dosages of these inhibitors are required to suppress tumor growth in animal studies. Other disadvantages of the antiangiogenic protein therapy include repeated injections, prolonged treatment, transmission of toxins and infectious particles, and high cost for manufacturing large amounts of protein molecules. Thus, alternative strategies need to be developed in order to improve the clinical settings of antiangiogenic therapy. Developments of these strategies are ongoing and they include identification of more potent inhibitors, antiangiogenic gene therapy, improvement of protein/compound half-lives in the circulation, increase of their concentrations at the disease location, and combinatorial therapies with approaches including chemotherapy, radiotherapy, and immunotherapy. Despite the above-mentioned disadvantages, a few inhibitors have entered into the early stages of clinical trials and

  12. Therapeutic Potential of Monoacylglycerol Lipase Inhibitors

    OpenAIRE

    Mulvihill, Melinda M.; Nomura, Daniel K.

    2012-01-01

    Marijuana and aspirin have been used for millennia to treat a wide range of maladies including pain and inflammation. Both cannabinoids, like marijuana, that exert anti-inflammatory action through stimulating cannabinoid receptors, and cyclooxygenase (COX) inhibitors, like aspirin, that suppress pro-inflammatory eicosanoid production have shown benefitial outcomes in mouse models of neurodegenerative diseases and cancer. Both cannabinoids and COX inhibitors, however, have untoward effects tha...

  13. Natural inhibitors of tumor-associated proteases

    International Nuclear Information System (INIS)

    The turnover and remodelling of extracellular matrix (ECM) is an essential part of many normal biological processes including development, morphogenesis, and wound healing. ECM turnover also occurs in severe pathological situations like artherosclerosis, fibrosis, tumor invasion and metastasis. The major proteases involved in this turnover are serine proteases (especially the urokinase-type plasminogen activator/plasmin system), matrix metalloproteases (a family of about 20 zinc-dependent endopeptidases including collagenases, gelatinases, stromelysins, and membrane-type metalloproteases), and cysteine proteases. In vivo, the activity of these proteases is tightly regulated in the extracellular space by zymogen activation and/or controlled inhibition. In the present review, we give an overview on the structure and biochemical properties of important tumor-associated protease inhibitors such as plasminogen activator inhibitor type 1 and type 2 (PAI-1, PAI-2), tissue inhibitors of metalloproteinases (TIMP-1, -2, -3, and -4), and the cysteine protease inhibitor cystatin C. Interestingly, some of these inhibitors of tumor-associated proteases display multiple functions which rather promote than inhibit tumor progression, when the presence of inhibitors in the tumor tissue is not balanced. (author)

  14. Development of Radiosensitizer using farnesyltransferase inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Jong Seok; Choe, Yong Kyung; Han, Mi Young; Kim, Kwang Dong [Korea Research Institute of Bioscience and Biotechnology, Taejon (Korea)

    1999-03-01

    We selected some compounds that were reported to have an activity of farneyltransferase inhibitor and tested the hypothesis that they might be used to radiosensitize cells transformed by ras oncogenes. The inhibition of ras processing using some, but not all, inhibitors resulted in higher levels of cell death after {gamma}-irradiation and increased radiosensitivity in H-ras-transformed NIH3T3 cells and MCF-10A human tumor cells. They did not induce additional cell death in control cells that doe not have ras mutation. Furthermore, the treatment of inhibitors alone induced a weak G0/G1 block, whereas inhibitors in combination with {gamma}-irradiation induced an additional enrichment in the G2/M phase of the cell cycle that typically represents irradiation-induced growth arrest. At present, the underling mechanism by which the farnesylltransferase inhibitors exert radiosensitizing effect is not known. In summary, our results suggest and lead to the possibility that some of farnesylation inhibitors may prove clinically useful not only as antitumor agents, but also radiosensitizers of tumors whose growth is dependent on ras function. (author). 15 refs., 10 figs., 4 tabs.

  15. Calcineurin inhibitors acutely improve insulin sensitivity without affecting insulin secretion in healthy human volunteers

    DEFF Research Database (Denmark)

    Øzbay, Aygen; Møller, Niels; Juhl, Claus;

    2012-01-01

    tacrolimus has been attributed to both beta cell dysfunction and impaired insulin sensitivity. WHAT THIS STUDY ADDS: This is the first trial to investigate beta cell function and insulin sensitivity using gold standard methodology in healthy human volunteers treated with clinically relevant doses of...... ciclosporin and tacrolimus. We document that both drugs acutely increase insulin sensitivity, while first phase and pulsatile insulin secretion remain unaffected. This study demonstrates that ciclosporin and tacrolimus have similar acute effects on glucose metabolism in healthy humans. AIM The introduction of...... of NODAT remains unclear. We sought to compare the impact of CsA and Tac on glucose metabolism in human subjects. METHODS: Ten healthy men underwent 5 h infusions of CsA, Tac and saline in a randomized, double-blind, crossover study. During infusion glucose metabolism was investigated using following...

  16. Basic nuclear processes affected by histone acetyltransferases and histone deacetylase inhibitors

    Czech Academy of Sciences Publication Activity Database

    Legartová, Soňa; Stixová, Lenka; Strnad, Hynek; Kozubek, Stanislav; Martinet, N.; Dekker, F.J.; Franěk, Michal; Bártová, Eva

    2013-01-01

    Roč. 5, č. 4 (2013), s. 379-396. ISSN 1750-1911 R&D Projects: GA MŠk(CZ) LD11020; GA ČR(CZ) GAP302/10/1022; GA ČR(CZ) GBP302/12/G157; GA ČR(CZ) GA13-07822S; GA ČR(CZ) EE2.3.30.0030 Institutional support: RVO:68081707 ; RVO:68378050 Keywords : cDNA microarray * DNA repair * epi-drug Subject RIV: BO - Biophysics; EB - Genetics ; Molecular Biology (UMG-J) Impact factor: 5.215, year: 2013

  17. CD38 expression and complement inhibitors affect response and resistance to daratumumab therapy in myeloma.

    Science.gov (United States)

    Nijhof, Inger S; Casneuf, Tineke; van Velzen, Jeroen; van Kessel, Berris; Axel, Amy E; Syed, Khaja; Groen, Richard W J; van Duin, Mark; Sonneveld, Pieter; Minnema, Monique C; Zweegman, Sonja; Chiu, Christopher; Bloem, Andries C; Mutis, Tuna; Lokhorst, Henk M; Sasser, A Kate; van de Donk, Niels W C J

    2016-08-18

    The anti-CD38 monoclonal antibody daratumumab is well tolerated and has high single agent activity in heavily pretreated relapsed and refractory multiple myeloma (MM). However, not all patients respond, and many patients eventually develop progressive disease to daratumumab monotherapy. We therefore examined whether pretreatment expression levels of CD38 and complement-inhibitory proteins (CIPs) are associated with response and whether changes in expression of these proteins contribute to development of resistance. In a cohort of 102 patients treated with daratumumab monotherapy (16 mg/kg), we found that pretreatment levels of CD38 expression on MM cells were significantly higher in patients who achieved at least partial response (PR) compared with patients who achieved less than PR. However, cell surface expression of the CIPs, CD46, CD55, and CD59, was not associated with clinical response. In addition, CD38 expression was reduced in both bone marrow-localized and circulating MM cells, following the first daratumumab infusion. CD38 expression levels on MM cells increased again following daratumumab discontinuation. In contrast, CD55 and CD59 levels were significantly increased on MM cells only at the time of progression. All-trans retinoic acid increased CD38 levels and decreased CD55 and CD59 expression on MM cells from patients who developed daratumumab resistance, to approximately pretreatment values. This resulted in significant enhancement of daratumumab-mediated complement-dependent cytotoxicity. Together, these data demonstrate an important role for CD38 and CIP expression levels in daratumumab sensitivity and suggest that therapeutic combinations that alter CD38 and CIP expression levels should be investigated in the treatment of MM. These trials were registered at www.clinicaltrials.gov as #NCT00574288 (GEN501) and #NCT01985126 (SIRIUS). PMID:27307294

  18. Systemic effects of treatment with mTOR inhibitors in tuberous sclerosis complex: a comprehensive review.

    Science.gov (United States)

    Sadowski, K; Kotulska, K; Schwartz, R A; Jóźwiak, S

    2016-04-01

    Tuberous sclerosis complex (TSC) is a genetic multisystem disorder associated with constitutive overactivation of the mammalian target of rapamycin (mTOR) pathway and characterized by development of benign tumours in various organs. mTOR inhibitors have proven to be effective in the targeted therapy of certain TSC-associated pathologies such as subependymal giant cell astrocytomas (SEGAs) and renal angiomyolipomas (AMLs). Accumulating experimental and clinical data suggest that mTOR inhibitors might have a systemic, disease-modifying influence on affected individuals. This systematic review provides an analysis of available clinical data concerning systemic effect of mTOR inhibitors and the influence of mTOR inhibition on different manifestations of TSC in individual patients. PMID:26403211

  19. The Affective Turn

    OpenAIRE

    Alí Lara; Giazú Enciso

    2013-01-01

    En la última década los estudios del afecto y las emociones han cobrado relevancia en las ciencias sociales. Esto no es simplemente una directriz de moda, es un indicador simultáneo de las modificaciones en la vida pública y de la experiencia subjetiva; a partir del cual se está transformando la producción de conocimiento. Tal tendencia ha sido conocida en la academia sajona como The Affective Turn, aquí traducido como “El giro afectivo” y que hasta el momento no ha incursionado como tal en l...

  20. Visual affect recognition

    CERN Document Server

    Stathopoulou, I-O

    2010-01-01

    It is generally known that human faces, as well as body motions and gestures, provide a wealth of information about a person, such as age, race, sex and emotional state. This monograph primarily studies the perception of facial expression of emotion, and secondarily of motion and gestures, with the purpose of developing a fully automated visual affect recognition system for use in modes of human/computer interaction. The book begins with a survey of the literature on emotion perception, followed by a description of empirical studies conducted with human participants and the construction of a '

  1. Combined effects of EGFR tyrosine kinase inhibitors and vATPase inhibitors in NSCLC cells

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Hyeon-Ok [KIRAMS Radiation Biobank, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of); Hong, Sung-Eun [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of); Kim, Chang Soon [Department of Microbiological Engineering, Kon-Kuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul, 143–701 (Korea, Republic of); Park, Jin-Ah; Kim, Jin-Hee; Kim, Ji-Young; Kim, Bora [KIRAMS Radiation Biobank, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of); Chang, Yoon Hwan; Hong, Seok-Il; Hong, Young Jun [Department of Laboratory Medicine, Korea Cancer Center Hospital, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of); Park, In-Chul, E-mail: parkic@kirams.re.kr [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of); Lee, Jin Kyung, E-mail: jklee@kirams.re.kr [KIRAMS Radiation Biobank, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of); Department of Laboratory Medicine, Korea Cancer Center Hospital, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of)

    2015-08-15

    Despite excellent initial clinical responses of non-small cell lung cancer (NSCLC) patients to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs), many patients eventually develop resistance. According to a recent report, vacuolar H + ATPase (vATPase) is overexpressed and is associated with chemotherapy drug resistance in NSCLC. We investigated the combined effects of EGFR TKIs and vATPase inhibitors and their underlying mechanisms in the regulation of NSCLC cell death. We found that combined treatment with EGFR TKIs (erlotinib, gefitinib, or lapatinib) and vATPase inhibitors (bafilomycin A1 or concanamycin A) enhanced synergistic cell death compared to treatments with each drug alone. Treatment with bafilomycin A1 or concanamycin A led to the induction of Bnip3 expression in an Hif-1α dependent manner. Knock-down of Hif-1α or Bnip3 by siRNA further enhanced cell death induced by bafilomycin A1, suggesting that Hif-1α/Bnip3 induction promoted resistance to cell death induced by the vATPase inhibitors. EGFR TKIs suppressed Hif-1α and Bnip3 expression induced by the vATPase inhibitors, suggesting that they enhanced the sensitivity of the cells to these inhibitors by decreasing Hif-1α/Bnip3 expression. Taken together, we conclude that EGFR TKIs enhance the sensitivity of NSCLC cells to vATPase inhibitors by decreasing Hif-1α/Bnip3 expression. We suggest that combined treatment with EGFR TKIs and vATPase inhibitors is potentially effective for the treatment of NSCLC. - Highlights: • Co-treatment with EGFR TKIs and vATPase inhibitors induces synergistic cell death • EGFR TKIs enhance cell sensitivity to vATPase inhibitors via Hif-1α downregulation • Co-treatment of these inhibitors is potentially effective for the treatment of NSCLC.

  2. SGLT2 Inhibitors and the Diabetic Kidney.

    Science.gov (United States)

    Fioretto, Paola; Zambon, Alberto; Rossato, Marco; Busetto, Luca; Vettor, Roberto

    2016-08-01

    Diabetic nephropathy (DN) is the most common cause of end-stage renal disease worldwide. Blood glucose and blood pressure control reduce the risk of developing this complication; however, once DN is established, it is only possible to slow progression. Sodium-glucose cotransporter 2 (SGLT2) inhibitors, the most recent glucose-lowering oral agents, may have the potential to exert nephroprotection not only through improving glycemic control but also through glucose-independent effects, such as blood pressure-lowering and direct renal effects. It is important to consider, however, that in patients with impaired renal function, given their mode of action, SGLT2 inhibitors are less effective in lowering blood glucose. In patients with high cardiovascular risk, the SGLT2 inhibitor empagliflozin lowered the rate of cardiovascular events, especially cardiovascular death, and substantially reduced important renal outcomes. Such benefits on DN could derive from effects beyond glycemia. Glomerular hyperfiltration is a potential risk factor for DN. In addition to the activation of the renin-angiotensin-aldosterone system, renal tubular factors, including SGLT2, contribute to glomerular hyperfiltration in diabetes. SGLT2 inhibitors reduce sodium reabsorption in the proximal tubule, causing, through tubuloglomerular feedback, afferent arteriole vasoconstriction and reduction in hyperfiltration. Experimental studies showed that SGLT2 inhibitors reduced hyperfiltration and decreased inflammatory and fibrotic responses of proximal tubular cells. SGLT2 inhibitors reduced glomerular hyperfiltration in patients with type 1 diabetes, and in patients with type 2 diabetes, they caused transient acute reductions in glomerular filtration rate, followed by a progressive recovery and stabilization of renal function. Interestingly, recent studies consistently demonstrated a reduction in albuminuria. Although these data are promising, only dedicated renal outcome trials will clarify whether

  3. Inhibitors of histone deacetylases enhance neurotoxicity of DNA damage.

    Science.gov (United States)

    Vashishta, A; Hetman, M

    2014-12-01

    The nonselective inhibitors of class I/II histone deacetylases (HDACs) including trichostatin A and the clinically used suberoylanilide hydroxamic acid (SAHA, vorinostat) are neuroprotective in several models of neuronal injury. Here, we report that in cultured cortical neurons from newborn rats and in the cerebral cortex of whole neonate rats, these HDAC inhibitors exacerbated cytotoxicity of the DNA double-strand break (DSB)-inducing anticancer drug etoposide by enhancing apoptosis. Similar neurotoxic interactions were also observed in neurons that were treated with other DNA damaging drugs including cisplatin and camptothecin. In addition, in rat neonates, SAHA increased cortical neuron apoptosis that was induced by a single injection of the NMDA receptor antagonist dizocilpine (MK801). In etoposide-treated neurons, the nonselective HDAC inhibition resulted in more DSBs. It also potentiated etoposide-induced accumulation and phosphorylation of the pro-apoptotic transcription factor p53. Moreover, nonselective HDAC inhibition exacerbated neuronal apoptosis that was induced by the overexpressed p53. Importantly, such effects cannot be fully explained by inhibition of HDAC1, which is known to play a role in DSB repair and regulation of p53. The specific HDAC1 inhibitor MS275 only moderately enhanced etoposide-induced neuronal death. Although in etoposide-treated neurons MS275 increased DSBs, it did not affect activation of p53. Our findings suggest that besides HDAC1, there are other class I/II HDACs that participate in neuronal DNA damage response attenuating neurotoxic consequences of genotoxic insults to the developing brain. PMID:25063076

  4. Cloning and Characterization of Two Potent Kunitz Type Protease Inhibitors from Echinococcus granulosus.

    Directory of Open Access Journals (Sweden)

    Shiwanthi L Ranasinghe

    2015-12-01

    Full Text Available The tapeworm Echinococcus granulosus is responsible for cystic echinococcosis (CE, a cosmopolitan disease which imposes a significant burden on the health and economy of affected communities. Little is known about the molecular mechanisms whereby E. granulosus is able to survive in the hostile mammalian host environment, avoiding attack by host enzymes and evading immune responses, but protease inhibitors released by the parasite are likely implicated. We identified two nucleotide sequences corresponding to secreted single domain Kunitz type protease inhibitors (EgKIs in the E. granulosus genome, and their cDNAs were cloned, bacterially expressed and purified. EgKI-1 is highly expressed in the oncosphere (egg stage and is a potent chymotrypsin and neutrophil elastase inhibitor that binds calcium and reduced neutrophil infiltration in a local inflammation model. EgKI-2 is highly expressed in adult worms and is a potent inhibitor of trypsin. As powerful inhibitors of mammalian intestinal proteases, the EgKIs may play a pivotal protective role in preventing proteolytic enzyme attack thereby ensuring survival of E. granulosus within its mammalian hosts. EgKI-1 may also be involved in the oncosphere in host immune evasion by inhibiting neutrophil elastase and cathepsin G once this stage is exposed to the mammalian blood system. In light of their key roles in protecting E. granulosus from host enzymatic attack, the EgKI proteins represent potential intervention targets to control CE. This is important as new public health measures against CE are required, given the inefficiencies of available drugs and the current difficulties in its treatment and control. In addition, being a small sized highly potent serine protease inhibitor, and an inhibitor of neutrophil chemotaxis, EgKI-1 may have clinical potential as a novel anti-inflammatory therapeutic.

  5. Cloning and Characterization of Two Potent Kunitz Type Protease Inhibitors from Echinococcus granulosus.

    Science.gov (United States)

    Ranasinghe, Shiwanthi L; Fischer, Katja; Zhang, Wenbao; Gobert, Geoffrey N; McManus, Donald P

    2015-12-01

    The tapeworm Echinococcus granulosus is responsible for cystic echinococcosis (CE), a cosmopolitan disease which imposes a significant burden on the health and economy of affected communities. Little is known about the molecular mechanisms whereby E. granulosus is able to survive in the hostile mammalian host environment, avoiding attack by host enzymes and evading immune responses, but protease inhibitors released by the parasite are likely implicated. We identified two nucleotide sequences corresponding to secreted single domain Kunitz type protease inhibitors (EgKIs) in the E. granulosus genome, and their cDNAs were cloned, bacterially expressed and purified. EgKI-1 is highly expressed in the oncosphere (egg) stage and is a potent chymotrypsin and neutrophil elastase inhibitor that binds calcium and reduced neutrophil infiltration in a local inflammation model. EgKI-2 is highly expressed in adult worms and is a potent inhibitor of trypsin. As powerful inhibitors of mammalian intestinal proteases, the EgKIs may play a pivotal protective role in preventing proteolytic enzyme attack thereby ensuring survival of E. granulosus within its mammalian hosts. EgKI-1 may also be involved in the oncosphere in host immune evasion by inhibiting neutrophil elastase and cathepsin G once this stage is exposed to the mammalian blood system. In light of their key roles in protecting E. granulosus from host enzymatic attack, the EgKI proteins represent potential intervention targets to control CE. This is important as new public health measures against CE are required, given the inefficiencies of available drugs and the current difficulties in its treatment and control. In addition, being a small sized highly potent serine protease inhibitor, and an inhibitor of neutrophil chemotaxis, EgKI-1 may have clinical potential as a novel anti-inflammatory therapeutic. PMID:26645974

  6. [Hematopoietic prostaglandin D synthase inhibitors for the treatment of duchenne muscular dystrophy].

    Science.gov (United States)

    Kamauchi, Shinya; Urade, Yoshihiro

    2011-11-01

    Duchenne muscular dystrophy (DMD) is a severe X-linked muscle disease, characterized by progressive skeletal muscle atrophy and weakness. DMD is caused by mutations in the dystrophin gene, which encodes for the cytoskeletal protein dystrophin. DMD is one of the most common types of muscular dystrophies, affecting approximately 1 in 3,500 boys. There is no complete cure for this disease. Clinical trials for gene transfer therapy as a treatment for DMD have been performed but mainly in animal models. Hematopoietic prostaglandin (PG) D synthase (H-PGDS) was found to be induced in grouped necrotic muscle fibers of DMD patients and animal models, mdx mice, and DMD dogs. We found an orally active H-PGDS inhibitor (HQL-79) and determined the 3D structure of the inhibitor-human H-PGDS complex by X-ray crystallography. Oral administration of HQL-79 markedly suppressed prostaglandin D2 (PGD2) production, reduced necrotic muscle volume, and improved muscle strength in mdx dystrophic mice. Based on the high-resolution 3D structures of the inhibitor-H-PGDS complex, we designed alternative H-PGDS inhibitors, which were 100- to 3000-times more potent than HQL-79, as assessed by in vitro and in vivo analyses. We used these novel inhibitors for the treatment of DMD dogs and confirmed that oral administration of these inhibitors prevented skeletal muscle atrophy and weakness by decreasing PGD2 production. These results indicate that PGD2, synthesized by H-PGDS, is involved in the expansion of muscle necrosis in DMD. Thus, inhibition of H-PGDS by using inhibitors is a novel therapy for DMD. PMID:22068479

  7. Versatile templates for the development of novel kinase inhibitors: Discovery of novel CDK inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Dwyer, Michael P.; Paruch, Kamil; Alvarez, Carmen; Doll, Ronald J.; Keertikar, Kerry; Duca, Jose; Fischmann, Thierry O.; Hruza, Alan; Madison, Vincent; Lees, Emma; Parry, David; Seghezzi, Wolfgang; Sgambellone, Nicole; Shanahan, Frances; Wiswell, Derek; Guzi, Timothy J. (SPRI)

    2008-06-30

    A series of four bicyclic cores were prepared and evaluated as cyclin-dependent kinase-2 (CDK2) inhibitors. From the in-vitro and cell-based analysis, the pyrazolo[1,5-a]pyrimidine core (represented by 9) emerged as the superior core for further elaboration in the identification of novel CDK2 inhibitors.

  8. Selective cell adhesion inhibitors: Barbituric acid based alpha4beta7--MAdCAM inhibitors.

    Science.gov (United States)

    Harriman, Geraldine C; Brewer, Matthias; Bennett, Robert; Kuhn, Cyrille; Bazin, Marc; Larosa, Greg; Skerker, Paul; Cochran, Nancy; Gallant, Debra; Baxter, Deborah; Picarella, Dominic; Jaffee, Bruce; Luly, Jay R; Briskin, Michael J

    2008-04-01

    A novel series of barbituric acid derivatives were identified as selective inhibitors of alpha4beta7 MAdCAM (mucosal addressin cell adhesion molecule-1) interactions via a high throughput screening exercise. These inhibitors were optimized to submicromolar potencies in whole cell adhesion assays, retaining their selectivity over alpha4beta1 VCAM. PMID:18331794

  9. Polyphenol oxidase inhibitor(s) from German cockroach (Blattella germanica) extract

    Science.gov (United States)

    An extract from German cockroach appears effective in inhibiting browning on apples and potatoes. Successful identification of inhibitor(s) of PPO from German cockroach would be useful to the fruit and vegetable segments of the food industry, due to the losses they incur from enzymatic browning. Ide...

  10. Effect of selective phosphodiesterase inhibitors on the rat eosinophil chemotactic response in vitro

    Directory of Open Access Journals (Sweden)

    Alves Alessandra C

    1997-01-01

    Full Text Available In the present study, we have performed a comparative analysis of the effect of selective inhibitors of phosphodiesterase (PDE type III, IV and V on eosinophil chemotaxis triggered by platelet activating factor (PAF and leukotriene B4 (LTB4 in vitro. The effect of the analogues N6-2'-O-dibutyryladenosine 3':5' cyclic monophosphate (Bt2 cyclic AMP and N2-2'-O- dibutyrylguanosine 3':5' cyclic monophosphate (Bt2 cyclic GMP has also been determined. The eosinophils were obtained from the peritoneal cavity of naive Wistar rats and purified in discontinuous Percoll gradients to 85-95% purity. We observed that pre-incubation of eosinophils with the PDE type IV inhibitor rolipram suppressed the chemotactic response triggered by PAF and LTB4, in association with an increase in the intracellular levels of cyclic AMP. In contrast, neither zaprinast (type V inhibitor nor type III inhibitors milrinone and SK&F 94836 affected the eosinophil migration. Only at the highest concentration tested did the analogue Bt2 cyclic AMP suppress the eosinophil chemotaxis, under conditions where Bt2 cyclic GMP was ineffective. We have concluded that inhibition of PDE IV, but not PDE III or V, was able to block the eosinophil chemotaxis in vitro, suggesting that the suppressive activity of selective PDE IV inhibitors on tissue eosinophil accumulation may, at least, be partially dependent on their ability to directly inhibit the eosinophil migration.

  11. Virtual Screening of Acetylcholinesterase Inhibitors Using the Lipinski’s Rule of Five and ZINC Databank

    Directory of Open Access Journals (Sweden)

    Pablo Andrei Nogara

    2015-01-01

    Full Text Available Alzheimer’s disease (AD is a progressive and neurodegenerative pathology that can affect people over 65 years of age. It causes several complications, such as behavioral changes, language deficits, depression, and memory impairments. One of the methods used to treat AD is the increase of acetylcholine (ACh in the brain by using acetylcholinesterase inhibitors (AChEIs. In this study, we used the ZINC databank and the Lipinski’s rule of five to perform a virtual screening and a molecular docking (using Auto Dock Vina 1.1.1 aiming to select possible compounds that have quaternary ammonium atom able to inhibit acetylcholinesterase (AChE activity. The molecules were obtained by screening and further in vitro assays were performed to analyze the most potent inhibitors through the IC50 value and also to describe the interaction models between inhibitors and enzyme by molecular docking. The results showed that compound D inhibited AChE activity from different vertebrate sources and butyrylcholinesterase (BChE from Equus ferus (EfBChE, with IC50 ranging from 1.69 ± 0.46 to 5.64 ± 2.47 µM. Compound D interacted with the peripheral anionic subsite in both enzymes, blocking substrate entrance to the active site. In contrast, compound C had higher specificity as inhibitor of EfBChE. In conclusion, the screening was effective in finding inhibitors of AChE and BuChE from different organisms.

  12. Clinical utility of the oral JAK inhibitor tofacitinib in the treatment of rheumatoid arthritis

    Directory of Open Access Journals (Sweden)

    Cutolo M

    2013-11-01

    Full Text Available Maurizio Cutolo, Marianna Meroni Research Laboratories and Academic Division of Clinical Rheumatology, Department of Internal Medicine, University of Genova, Genova, Italy Abstract: Immune/inflammatory cells act in rheumatoid arthritis (RA-affected patients by synthesizing several inflammatory mediators, including cytokines that initiate intracellular signaling. Recently, small molecule inhibitors of transduction and transcription signals that influence the intracellular pathways (such as the Janus kinase [JAK] family of tyrosine kinases have been tested for RA treatment. Four members of the JAK family are known: JAK1, JAK2, JAK3, and TyK2. JAK1/JAK3 constitutively binds to the cytoplasmic portion of the cytokine receptor – the common gamma chain – that represents a common subunit of several cytokines involved in T-cell and natural killer cell development, as well as in B-cell activation. Tofacitinib is an oral JAK inhibitor that is now available and effective in RA treatment, as shown in multiple Phase II and Phase III clinical trials. However, long-term safety data and comparisons with other disease-modifying antirheumatic drugs and small molecule inhibitors are necessary to better determine the role of tofacitinib in RA. Keywords: Janus kinase inhibitors, tofacitinib, rheumatoid arthritis, kinases, small molecules inhibitors, intracellular signaling

  13. PEGylated DX-1000: Pharmacokinetics and Antineoplastic Activity of a Specific Plasmin Inhibitor

    Directory of Open Access Journals (Sweden)

    Laetitia Devy

    2007-11-01

    Full Text Available Novel inhibitors of the urokinase-mediated plasminogen (plg activation system are potentially of great clinical benefit as anticancer treatments. Using phage display, we identified DX-1000 a tissue factor pathway inhibitor-derived Kunitz domain protein which is a specific high-affinity inhibitor of plasmin (pin (Ki = 99 pM. When tested in vitro, DX-1000 blocks plasminmediated pro-matrix metal loproteinase-9 (proMMP-9 activation on cells and dose-dependently inhibits tube formation, while not significantly affecting hemostasis and coagulation. However, this low-molecular weight protein inhibitor (~ 7 kDa exhibits rapid plasma clearance in mice and rabbits, limiting its potential clinical use in chronic diseases. After site-specific PEGylation, DX-1000 retains its activity and exhibits a decreased plasma clearance. This PEGylated derivative is effective in vitro, as well as potent in inhibiting tumor growth of green fluorescent protein (GFP-labeled MDA-MB-231 cells. 4PEG-DX-1000 treatment causes a significant reduction of urokinase-type plasminogen activator (uPA and plasminogen expressions, a reduction of tumor proliferation, and vascularization. 4PEG-DX-1000 treatment significantly decreases the level of active mitogenactivated protein kinase (MAPK in the primary tumors and reduces metastasis incidence. Together, our results demonstrate the potential value of plasmin inhibitors as therapeutic agents for blocking breast cancer growth and metastasis.

  14. A Trypsin Inhibitor from Clitoria fairchildiana Cotyledons is Active Against Digestive Enzymes of Aedes aegypti Larvae.

    Science.gov (United States)

    de Oliveira, Lucilene O; Fernandes, Kátia V S; Pádua, Dayanni de Souza; Carvalho, André de O; Lemos, Francisco J A; Gomes, Valdirene M; Oliveira, Antônia E A; Ferreira, André T da Silva; Perales, Jonas

    2015-01-01

    Aedes aegypti, the principal mosquito vector of yellow fever, dengue fever and chikungunya fever virus-transmitted diseases, is an insect closely associated with humans and their housing habitats. As there is no commercially available vaccine, prevention is the most suggested form of avoiding disease spreading and a number of studies are being developed in order to give support to vector control operations. The present study reports on the identification of a trypsin inhibitor isolated from cotyledons of the Clitoria fairchildiana amazonic tree seeds, which was able to reduce by 87.93 % the activity of digestive enzymes of fourth instar A. aegypti larva. A partial amino acid sequence showed strong similarity with sequences from several trypsin inhibitors already reported in the literature. The 13,000 Da isolated inhibitor was seen to be active solely against trypsin-like enzymes, neither acting on papain, α-amylase nor on other serine proteases, such as elastase, chymotrypsin or subtilisin. At least six from seven active digestive proteases from A. aegypti larvae, visualized by zymography, were severely affected soon after exposed to the inhibitor. The strong and specific action of the isolated inhibitor against trypsin digestive enzymes of this insect vector led us to believe that this protein may be a good candidate for a prospective alternative biocontrol method. PMID:26156641

  15. [Physiological functions of endoplasmic and sarcoplasmic reticulum Ca pump and pharmacology of inhibitors of the pump].

    Science.gov (United States)

    Watanabe, M; Shigekawa, M

    1993-09-01

    This review is derived from the symposium held at the 66th Annual Meeting of the Japanese Pharmacological Society (March, 1993). The symposium consisted of six invited papers whose general theme was the application of recently found ATPase inhibitors selective to SR- and ER-Ca(2+)-ATPase to the analyses of the physiological and pharmacological roles of endoplasmic and sarcoplasmic reticulum Ca stores. Inhibitors used were: thapsigargin, cyclopiazonic acid, 2,5-di-(t-butyl)-1,4-benzohydroquinone and 3',3",5',5"-tetraiodosulfophthalein. Gingerol was found to facilitate the action of the ATPase. In either smooth, cardiac or skeletal muscle, sympathetic neurons or several cell lines these inhibitors affected a variety of cell functions and conditions such as contraction, ionic conductance and excitability of the plasma membrane, regulation of intracellular free Ca2+ concentration, transport of viral glycoprotein to the cell surface. Many of these studies utilized either single or cultured cell preparations or skinned muscle. These inhibitors were shown to be useful tools for investigating the SR and ER functioning as Ca sources or Ca sequestrating pumps, and further for estimating the contribution of ER or SR to regulating the flux of Ca2+ and other ions through the plasma membrane. Results of analyses using these inhibitors are discussed. PMID:8406230

  16. Basis Tetrapeptides as Potent Intracellular Inhibitors of type A Botulinum Neurotoxin Protease Activity

    Energy Technology Data Exchange (ETDEWEB)

    Hale, M.; Swaminathan, S.; Oyler, G.; Ahmed, S. A.

    2011-01-21

    Botulinum neurotoxins (BoNT) are the most potent of all toxins that cause flaccid muscle paralysis leading to death. They are also potential biothreat agents. A systematic investigation of various short peptide inhibitors of the BoNT protease domain with a 17-residue peptide substrate led to arginine-arginine-glycine-cysteine having a basic tetrapeptide structure as the most potent inhibitor. When assayed in the presence of dithiothreitol (DTT), the inhibitory effect was drastically reduced. Replacing the terminal cysteine with one hydrophobic residue eliminated the DTT effect but with two hydrophobic residues made the pentapeptide a poor inhibitor. Replacing the first arginine with cysteine or adding an additional cysteine at the N terminus did not improve inhibition. When assessed using mouse brain lysates, the tetrapeptides also inhibited BoNT/A cleavage of the endogenous SNAP-25. The peptides penetrated the neuronal cell lines, N2A and BE(2)-M17, without adversely affecting metabolic functions as measured by ATP production and P-38 phosphorylation. Biological activity of the peptides persisted within cultured chick motor neurons and rat and mouse cerebellar neurons for more than 40 h and inhibited BoNT/A protease action inside the neurons in a dose- and time-dependent fashion. Our results define a tetrapeptide as the smallest peptide inhibitor in the backdrop of a large substrate protein of 200+ amino acids having multiple interaction regions with its cognate enzyme. The inhibitors should also be valuable candidates for drug development.

  17. Material and Affective Movements

    DEFF Research Database (Denmark)

    Rasmussen, Lisa Rosén

    2014-01-01

    This chapter offers a study of life at school as remembered by groups of people who finished secondary school in the 1950s, 1970s and 1990s. The article draws up three generational portraits based on in-depth interviews that demonstrate how school life is remembered in complex and textural ways....... The chapter traces the former pupil’s memories of physical and affective movements within the larger context of school and discovers surprisingly diverse modes of knowing, relating, and attending to things, teachers and classmates among and between the three generations. It thus taps into the rich...... demonstrates how the use of spoken memories is a rewarding source for the writing about school from the pupils’ perspective....

  18. Affective World Literature

    DEFF Research Database (Denmark)

    Vilslev, Annette Thorsen

    The PhD dissertation compares the literary theory and novels of modern Japanese writer Natsume Sōseki. It reads Sōseki’s Theory of Literature (2009, Bungakuron, 1907) as an inherently comparative and interdisciplinary approach to theorizing feelings in world literature. More broadly, the...... dissertation investigates the critical negotiation of the novel as a travelling genre in Japan in the beginning of the 20th century, and, more specifically, Sōseki’s work in relation to world literature and affect theory. Sōseki’s work is highly influential in Japan and East Asia, and his novels widely...... circulated beyond Japan. Using Sōseki’s theory as an example, and by comparing it to other theories, the dissertation argues that comparative literature needs to include not only more non-Western literature but also more non-Western literary theories in the ongoing debate of world literature. Close...

  19. Enhanced effects by 4-phenylbutyrate in combination with RTK inhibitors on proliferation in brain tumor cell models

    International Nuclear Information System (INIS)

    Highlights: → The histone deacetylase inhibitor 4-phenylbutyrate substantially enhance efficacy of the receptor tyrosine kinase inhibitors gefitinib or vandetanib in glioma and medulloblastoma cell lines. → Cell death increases and clonogenic survival is reduced in the combination treatments, over mono-therapy. → Combination treatments with these drugs may improve clinical outcome for cancer therapy. -- Abstract: We have investigated in vitro effects of anticancer therapy with the histone deacetylase inhibitor (HDACi) 4-phenylbutyrate (4-PB) combined with receptor tyrosine kinase inhibitors (RTKi) gefitinib or vandetanib on the survival of glioblastoma (U343MGa) and medulloblastoma (D324Med) cells. In comparison with individual effects of these drugs, combined treatment with gefitinib/4-PB or vandetanib/4-PB resulted in enhanced cell killing and reduced clonogenic survival in both cell lines. Our results suggest that combined treatment using HDACi and RTKi may beneficially affect the outcome of cancer therapy.

  20. Identification of cytochrome P450 2D6 and 2C9 substrates and inhibitors by QSAR analysis

    DEFF Research Database (Denmark)

    Jónsdóttir, Svava Ósk; Ringsted, Tine; Nikolov, Nikolai G.;

    2012-01-01

    This paper presents four new QSAR models for CYP2C9 and CYP2D6 substrate recognition and inhibitor identification based on human clinical data. The models were used to screen a large data set of environmental chemicals for CYP activity, and to analyze the frequency of CYP activity among these...... compounds. A large fraction of these chemicals were found to be CYP active, and thus potentially capable of affecting human physiology. 20% of the compounds within applicability domain of the models were predicted to be CYP2C9 substrates, and 17% to be inhibitors. The corresponding numbers for CYP2D6 were 9......% and 21%. Where the majority of CYP2C9 active compounds were predicted to be both a substrate and an inhibitor at the same time, the CYP2D6 active compounds were primarily predicted to be only inhibitors. It was demonstrated that the models could identify compound classes with a high occurrence of...

  1. Enhanced effects by 4-phenylbutyrate in combination with RTK inhibitors on proliferation in brain tumor cell models

    Energy Technology Data Exchange (ETDEWEB)

    Marino, Ana-Maria [Department of Clinical Neuroscience, Karolinska Institutet, Stockholm (Sweden); Center for Molecular Medicine CMM, Karolinska University Hospital, Stockholm (Sweden); Sofiadis, Anastasios [Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm (Sweden); Department of Oncology-Pathology, Karolinska Institutet, Stockholm (Sweden); Center for Molecular Medicine CMM, Karolinska University Hospital, Stockholm (Sweden); Baryawno, Ninib; Johnsen, John Inge [Department of Women' s and Children' s Health, Karolinska Institutet, Stockholm (Sweden); Larsson, Catharina [Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm (Sweden); Center for Molecular Medicine CMM, Karolinska University Hospital, Stockholm (Sweden); Vukojevic, Vladana [Department of Clinical Neuroscience, Karolinska Institutet, Stockholm (Sweden); Center for Molecular Medicine CMM, Karolinska University Hospital, Stockholm (Sweden); Ekstroem, Tomas J., E-mail: tomas.ekstrom@ki.se [Department of Clinical Neuroscience, Karolinska Institutet, Stockholm (Sweden); Center for Molecular Medicine CMM, Karolinska University Hospital, Stockholm (Sweden)

    2011-07-22

    Highlights: {yields} The histone deacetylase inhibitor 4-phenylbutyrate substantially enhance efficacy of the receptor tyrosine kinase inhibitors gefitinib or vandetanib in glioma and medulloblastoma cell lines. {yields} Cell death increases and clonogenic survival is reduced in the combination treatments, over mono-therapy. {yields} Combination treatments with these drugs may improve clinical outcome for cancer therapy. -- Abstract: We have investigated in vitro effects of anticancer therapy with the histone deacetylase inhibitor (HDACi) 4-phenylbutyrate (4-PB) combined with receptor tyrosine kinase inhibitors (RTKi) gefitinib or vandetanib on the survival of glioblastoma (U343MGa) and medulloblastoma (D324Med) cells. In comparison with individual effects of these drugs, combined treatment with gefitinib/4-PB or vandetanib/4-PB resulted in enhanced cell killing and reduced clonogenic survival in both cell lines. Our results suggest that combined treatment using HDACi and RTKi may beneficially affect the outcome of cancer therapy.

  2. Anticipated affect and behavioral choice.

    NARCIS (Netherlands)

    R. Richard; J. van der Pligt; N.K. de Vries

    1996-01-01

    Most research on the impact of affect on attitudes and behavior emphasizes the effect of past and present affective reactions. In this article we focus on anticipated, postbehavioral, affective reactions. The influence of anticipated affective reactions on a number of behaviors was investigated in t

  3. Recent advances in the field of tubulin polymerization inhibitors.

    Science.gov (United States)

    Prinz, Helge

    2002-12-01

    In recent years, enormous progress has been made in the field of tubulin targeting agents. Several companies and academic laboratories have entered this field and competition has become very strong. Nevertheless, clinically promising compounds often face substantial limitations, such as high systemic toxicity, poor water solubility and bioavailability, as well as complex synthesis and isolation procedures. As a drawback of established drugs, like paclitaxel or the vinca alkaloids, the outcome of cancer chemotherapy is often affected by the emergence of the multidrug resistance phenotype. Among the recently disclosed tubulin polymerization inhibitors, there are several interesting low molecular weight compounds with improved oral bioavailability and demonstrated activity against multi-drug resistance positive phenotypes. As documented by the imidazole-based combretastatin analogs, to name just one example, chemical optimization of a lead structure resulted in compounds with potent in vitro and in vivo activity along with appropriate pharmacodynamic and pharmacokinetic requirements for a potential therapeutic candidate. Currently, several compounds are undergoing Phase I or Phase II clinical trials, among them orally bioavailable sulfonamides or dolastatin 10. Several other compounds are close to entering Phase I trials. The purpose of this review is to focus on the most recent advances in tubulin polymerization inhibitors from a survey of the published patent literature and related publications between late 1999 and April 2002. However, biological data, especially for the inhibition of tubulin polymerization, obtained from different laboratories cannot easily be compared. PMID:12503216

  4. KRI-1314: an orally effective inhibitor of human renin.

    Science.gov (United States)

    Etoh, Y; Miyazaki, M; Saitoh, H; Toda, N

    1993-09-01

    Biochemical and pharmacological properties of KRI-1314, a newly synthesized, low molecular weight (M.W.: 690) renin inhibitor, were investigated in vitro and in vivo. The novel amino acid norstatine, which is shorter in chain length than the well-known statine, was incorporated into KRI-1314 as a tetrahedral transition-state analogue for the Leu10-Val11 scissile peptide in the renin substrate. KRI-1314 more strongly inhibited plasma renins from primates than those from dogs, rabbits, guinea pigs and rats. KRI-1314 competitively inhibited highly-purified human renin with a Ki value of 9.9 x 10(-10) M. KRI-1314 strongly inhibited the tissue renin-like activities of various organs from Japanese monkeys, with IC50 values on the order of 10(-8) M. KRI-1314 was also very stable in various tissue homogenates from Japanese monkeys. Both intravenous (from 0.25 to 3 mg/kg) and oral (10 and 30 mg/kg) administration of KRI-1314 to anesthetized and conscious sodium-depleted Japanese monkeys, respectively, significantly lowered the blood pressure and plasma renin activity without affecting the heart rate. In Japanese monkeys, KRI-1314 was continuously detected in the plasma up to at least 7 hr after oral administration of 10 and 30 mg/kg. These results demonstrate that KRI-1314 is a highly potent, primate-selective and long-lasting oral renin inhibitor with a blood pressure lowering effect. PMID:8271523

  5. Janus kinase inhibitors: jackpot or potluck?

    Directory of Open Access Journals (Sweden)

    Pavithran Keechilat

    2012-06-01

    Full Text Available The reports of a unique mutation in the Janus kinase-2 gene (JAK2 in polycythemia vera by several independent groups in 2005 quickly spurred the development of the Janus kinase inhibitors. In one of the great victories of translational research in recent times, the first smallmolecule Janus kinase inhibitor ruxolitinib entered a phase I trial in 2007. With the approval of ruxolitinib by the US Federal Drug Administration in November 2011 for high-risk and intermediate-2 risk myelofibrosis, a change in paradigm has occurred in the management of a subset of myeloproliferative neoplasms (MPN: primary myelofibrosis, post-polycythemia vera myelofibrosis, and post-essential thrombocythemia myelofibrosis. Whereas the current evidence for ruxolitinib only covers high-risk and intermediate-2 risk myelofibrosis, inhibitors with greater potency are likely to offer better disease control and survival advantage in patients belonging to these categories, and possibly to the low-risk and intermediate-1 risk categories of MPN as well. But use of the Janus kinase inhibitors also probably has certain disadvantages, such as toxicity, resistance, withdrawal phenomenon, non-reversal of histology, and an implausible goal of disease clone eradication, some of which could offset the gains. In spite of this, Janus kinase inhibitors are here to stay, and for use in more than just myeloproliferative neoplasms.

  6. The norepinephrine reuptake inhibitor reboxetine is more potent in treating murine narcoleptic episodes than the serotonin reuptake inhibitor escitalopram.

    Science.gov (United States)

    Schmidt, Christian; Leibiger, Judith; Fendt, Markus

    2016-07-15

    One of the major symptoms of narcolepsy is cataplexy, a sudden loss of muscle tone. Despite the advances in understanding the neuropathology of narcolepsy, cataplexy is still treated symptomatically with antidepressants. Here, we investigate in a murine narcolepsy model the hypothesis that the antidepressants specifically blocking norepinephrine reuptake are more potent in treating narcoleptic episodes than the antidepressants blocking of serotonin reuptake. Furthermore, we tested the effects of α1 receptor stimulation and blockade, respectively, on narcoleptic episodes. Orexin-deficient mice were treated with different doses of the norepinephrine reuptake inhibitor reboxetine, the serotonin reuptake inhibitor escitalopram, the α1 receptor agonist cirazoline or the α1 receptor antagonist prazosin. The effect of these treatments on narcoleptic episodes was tested. Additionally, potential treatment effects on locomotor activity in an open-field were tested. Reboxetine (doses ≥0.55mg/kg) as well as escitalopram (doses ≥3.0mg/kg) dose-dependently reduced the number of narcoleptic episodes in orexin-deficient mice. The ED50 for reboxetine (0.012mg/kg) was significantly lower than for escitalopram (0.44mg/kg). Cirazoline and prazosin did not affect narcoleptic episodes. Furthermore, cirazoline but not the other compounds reduced locomotor activity of the mice. The present study strongly supports the hypothesis that a specific blockade of norepinephrine reuptake is more potent in treating cataplexy than a specific blockade of serotonin reuptake. This argues for the development of more specific norepinephrine reuptake inhibitors for the treatment of narcolepsy. PMID:27118715

  7. Chalcone-based Selective Inhibitors of a C4 Plant Key Enzyme as Novel Potential Herbicides

    Science.gov (United States)

    Nguyen, G. T. T.; Erlenkamp, G.; Jäck, O.; Küberl, A.; Bott, M.; Fiorani, F.; Gohlke, H.; Groth, G.

    2016-06-01

    Weeds are a challenge for global food production due to their rapidly evolving resistance against herbicides. We have identified chalcones as selective inhibitors of phosphoenolpyruvate carboxylase (PEPC), a key enzyme for carbon fixation and biomass increase in the C4 photosynthetic pathway of many of the world’s most damaging weeds. In contrast, many of the most important crop plants use C3 photosynthesis. Here, we show that 2‧,3‧,4‧,3,4-Pentahydroxychalcone (IC50 = 600 nM) and 2‧,3‧,4‧-Trihydroxychalcone (IC50 = 4.2 μM) are potent inhibitors of C4 PEPC but do not affect C3 PEPC at a same concentration range (selectivity factor: 15–45). Binding and modeling studies indicate that the active compounds bind at the same site as malate/aspartate, the natural feedback inhibitors of the C4 pathway. At the whole plant level, both substances showed pronounced growth-inhibitory effects on the C4 weed Amaranthus retroflexus, while there were no measurable effects on oilseed rape, a C3 plant. Growth of selected soil bacteria was not affected by these substances. Our chalcone compounds are the most potent and selective C4 PEPC inhibitors known to date. They offer a novel approach to combat C4 weeds based on a hitherto unexplored mode of allosteric inhibition of a C4 plant key enzyme.

  8. The affective life of semiotics

    OpenAIRE

    J. S. Hutta

    2015-01-01

    The paper challenges writings on affect that locate affective dynamism in autonomic bodily responses while positing discourse and language as "capturing" affect. To move beyond such "verticalism", the paper seeks to further an understanding of language, and semiotics more broadly, as itself affective. Drawing on participatory research conducted in Rio de Janeiro, it uses poetic expression as a paradigmatic case of the affective life of semiotics. Conceptually, it builds on Guat...

  9. The use of selective serotonin reuptake inhibitors in eating disorders.

    Science.gov (United States)

    Mayer, L E; Walsh, B T

    1998-01-01

    The introduction of selective serotonin reuptake inhibitors (SSRIs), which are, in general, safer and more easily tolerated than conventional antidepressants, has had a profound effect on the treatment of affective illnesses and obsessive-compulsive disorder (OCD). A number of symptoms associated with eating disorders overlap those of depression and OCD, suggesting a theoretical and practical case for evaluating the SSRIs in the treatment of anorexia nervosa, bulimia nervosa, binge-eating disorder, and obesity. Despite the expectations for SSRIs in the treatment of eating disorders, clinical investigations have yielded mixed results. In this paper, results from clinical studies of SSRIs (with and without concomitant psychotherapy) in the treatment of anorexia and bulimia nervosa, binge eating disorder, and obesity are reviewed, directions for future research are suggested, and practical recommendations for the clinician are provided. PMID:9786308

  10. Paraffin wax deposits and chemical inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Mendell, J.L.

    1970-01-01

    Solutions to this problem becomes necessary with the advent of extremely deep production, offshore production, and the probability of ocean-floor completions. The reasons for paraffin-wax accumulations are many and difficult to pinpoint. Inhibition of these paraffin deposits appears to be the best solution. Paraffin solvents and inhibitors are as follows: solvents, wetting agents, dispersants, and crystal modifiers. Solvents are effective, but can harm a refinery catalyst and create health hazards. Wetting agents and dispersants comprise the majority of chemicals used as paraffin wax inhibitors. Crystal modifiers are relatively new and may provide the most efficient means of reducing deposition. Evaluations of chemical paraffin inhibitors are outlined. Field test results which consider the various chemicals tested may give satisfactory results in determining which particular chemical can solve the problem of the particular situation. (38 refs.)

  11. Cough Syncope due to ACE Inhibitor

    Directory of Open Access Journals (Sweden)

    Filiz Koc

    2015-09-01

    Full Text Available Syncope is defined as a transient loss of consciousness due to sudden temporary decline in cerebral perfusion. Cough syncope is classically seen in middle aged obese men with obstructive pulmonary disease. In patients that use Angiotensin converting enzyme (ACE inhibitors, a dry persistent cough can emerge due to the side effects of this medication. Seventy years old male patient that use ACE inhibitor for hypertension accepted to the clinic with the complaint of syncope. A bout of coughing has developed during electroencephalography recording and 10 seconds in duration of subcortical like epileptiform discharges were viewed. The ACE inhibitor the patient was receiving was replaced with calcium channel blocker and no complaint was observed during the follow up period. [Cukurova Med J 2015; 40(3.000: 619-622

  12. Topoisomerase I inhibitors: camptothecins and beyond.

    Science.gov (United States)

    Pommier, Yves

    2006-10-01

    Nuclear DNA topoisomerase I (TOP1) is an essential human enzyme. It is the only known target of the alkaloid camptothecin, from which the potent anticancer agents irinotecan and topotecan are derived. As camptothecins bind at the interface of the TOP1-DNA complex, they represent a paradigm for interfacial inhibitors that reversibly trap macromolecular complexes. Several camptothecin and non-camptothecin derivatives are being developed to further increase anti-tumour activity and reduce side effects. The mechanisms and molecular determinants of tumour response to TOP1 inhibitors are reviewed, and rational combinations of TOP1 inhibitors with other drugs are considered based on current knowledge of repair and checkpoint pathways that are associated with TOP1-mediated DNA damage. PMID:16990856

  13. Synthesis of amino heterocycle aspartyl protease inhibitors.

    Science.gov (United States)

    Chambers, Rachel K; Khan, Tanweer A; Olsen, David B; Sleebs, Brad E

    2016-06-14

    Aspartyl proteases are important pharmacological targets. Historically aspartyl proteases have been commonly targeted with transition state derived peptidomimetics. The strategy to develop aspartyl protease inhibitors has undertaken a dramatic paradigm shift in the last 10 years. The pharmaceutical industry in 2005 disclosed several scaffolds or "head groups" that prompted the field to move beyond peptidomimetic derived inhibitors. Since the discovery of the first amino heterocycle aspartyl protease inhibitor, the amino hydantoin, industry and academia have positioned themselves for a foothold on the new molecular space, designing a variety of related "head groups". Both the design and synthetic efforts involved in constructing these scaffolds are varied and complex. Here we highlight the synthetic strategies used to access these amino heterocycle scaffolds. PMID:27143279

  14. Functional non-nucleoside adenylyl cyclase inhibitors.

    Science.gov (United States)

    Lelle, Marco; Hameed, Abdul; Ackermann, Lisa-Maria; Kaloyanova, Stefka; Wagner, Manfred; Berisha, Filip; Nikolaev, Viacheslav O; Peneva, Kalina

    2015-05-01

    In this study, we describe the synthesis of novel functional non-nucleoside adenylyl cyclase inhibitors, which can be easily modified with thiol containing biomolecules such as tumour targeting structures. The linkage between inhibitor and biomolecule contains cleavable bonds to enable efficient intracellular delivery in the reductive milieu of the cytosol as well as in the acidic environment within endosomes and lysosomes. The suitability of this synthetic approach was shown by the successful bioconjugation of a poor cell-permeable inhibitor with a cell-penetrating peptide. Additionally, we have demonstrated the excellent inhibitory effect of the compounds presented here in a live-cell Förster resonance energy transfer-based assay in human embryonic kidney cells. PMID:25319071

  15. Drug screening for influenza neuraminidase inhibitors

    Institute of Scientific and Technical Information of China (English)

    LIU; Ailin; CAO; Hongpeng; DU; Guanhua

    2005-01-01

    Neuraminidase (NA) is one of the most important targets to screen the drugs of anti-influenza virus A and B. After virtual screening approaches were applied to a compound database which possesses more than 10000 compound structures, 160 compounds were selected for bioactivity assay, then a High Throughput Screening (HTS) model established for influenza virus NA inhibitors was applied to detect these compounds. Finally, three compounds among them displayed higher inhibitory activities, the range of their IC50 was from 0.1 μmol/L to 3μmol/L. Their structural scaffolds are novel and different from those of NA inhibitors approved for influenza treatment, and will be useful for the design and research of new NA inhibitors. The resuit indicated that the combination of virtual screening with HTS was very significant to drug screening and drug discovery.

  16. Preliminary studies on vigna unguiculata trypsin inhibitor

    International Nuclear Information System (INIS)

    Investigation on the presence of trypsin inhibitor in vigna unguiculata at three stages of ripeness, i.e. as young beans obtained from first harvest usually consumed as vegetable, seed from beans picked two weeks after the first harvest and seed from beans picked four weeks after the first harvest, has been carried out. The conclusion drawn from this experiment showed the existence of trypsin inhibitor at those stages of ripeness. It is found that the older the stage of ripeness the greater the specific activity of trypsin inhibitor. Evidently the heated extract loss its antitryptic activity progressively with increasing heatings periods. Extract heated on a water bath at a constant temperature of 78 deg C during 20, 40 and 60 minutes, loss its antitryptic activity of about 53, 78 and 96% respectively. (author)

  17. Use of acetylcholinesterase inhibitors in Alzheimer's disease.

    Science.gov (United States)

    Moghul, S; Wilkinson, D

    2001-09-01

    Alzheimer's disease is a growing problem in an aging Western world, estimated to have cost the US economy USD 1.75 trillion. Until recently, the management of Alzheimer's disease largely comprised support for the family, nursing care and the use of unlicensed medication to control behavioral disturbances. The three new acetylcholinesterase inhibitors licensed to treat Alzheimer's disease (donepezil, rivastigmine and galantamine) have provided clinicians with a major impetus to their desire to diagnose and treat this lethal disease. Their effects on cognition are proven. More recent work on the effects of acetylcholinesterase inhibitors on behavioral symptoms, activities of daily living and caregiver burden have also been encouraging. Emerging work indicates their likely efficacy in other dementias (e.g., vascular dementia, dementia with Lewy bodies). This review summarizes the evidence concerning the impact of acetylcholinesterase inhibitors in dementia both currently and over the next 5 years. PMID:19811047

  18. Endogenous Matrix-Derived Inhibitors of Angiogenesis

    Directory of Open Access Journals (Sweden)

    Hans Petter Eikesdal

    2010-09-01

    Full Text Available Endogenous inhibitors of angiogenesis are proteins or fragments of proteins that are formed in the body, which can inhibit the angiogenic process. These molecules can be found both in the circulation and sequestered in the extracellular matrix (ECM surrounding cells. Many matrix-derived inhibitors of angiogenesis, such as endostatin, tumstatin, canstatin and arresten, are bioactive fragments of larger ECM molecules. These substances become released upon proteolysis of the ECM and the vascular basement membrane (VBM by enzymes of the tumor microenvironment. Although the role of matrix-derived angiogenesis inhibitors is well studied in animal models of cancer, their role in human cancers is less established. In this review we discuss the current knowledge about these molecules and their potential use as cancer therapeutics and biomarkers.

  19. Enzyme inhibitor studies reveal complex control of methyl-D-erythritol 4-phosphate (MEP pathway enzyme expression in Catharanthus roseus.

    Directory of Open Access Journals (Sweden)

    Mei Han

    Full Text Available In Catharanthus roseus, the monoterpene moiety exerts a strong flux control for monoterpene indole alkaloid (MIA formation. Monoterpene synthesis depends on the methyl-D-erythritol 4-phosphate (MEP pathway. Here, we have explored the regulation of this pathway in response to developmental and environmental cues and in response to specific enzyme inhibitors. For the MEP pathway entry enzyme 1-deoxy-D-xylulose 5-phosphate synthase (DXS, a new (type I DXS isoform, CrDXS1, has been cloned, which, in contrast to previous reports on type II CrDXS, was not transcriptionally activated by the transcription factor ORCA3. Regulation of the MEP pathway in response to metabolic perturbations has been explored using the enzyme inhibitors clomazone (precursor of 5-ketochlomazone, inhibitor of DXS and fosmidomycin (inhibitor of deoxyxylulose 5-phosphate reductoisomerase (DXR, respectively. Young leaves of non-flowering plants were exposed to both inhibitors, adopting a non-invasive in vivo technique. Transcripts and proteins of DXS (3 isoforms, DXR, and hydroxymethylbutenyl diphosphate synthase (HDS were monitored, and protein stability was followed in isolated chloroplasts. Transcripts for DXS1 were repressed by both inhibitors, whereas transcripts for DXS2A&B, DXR and HDS increased after clomazone treatment but were barely affected by fosmidomycin treatment. DXS protein accumulated in response to both inhibitors, whereas DXR and HDS proteins were less affected. Fosmidomycin-induced accumulation of DXS protein indicated substantial posttranscriptional regulation. Furthermore, fosmidomycin effectively protected DXR against degradation in planta and in isolated chloroplasts. Thus our results suggest that DXR protein stability may be affected by substrate binding. In summary, the present results provide novel insight into the regulation of DXS expression in C. roseus in response to MEP-pathway perturbation.

  20. Enzyme Inhibitor Studies Reveal Complex Control of Methyl-D-Erythritol 4-Phosphate (MEP) Pathway Enzyme Expression in Catharanthus roseus

    Science.gov (United States)

    Han, Mei; Heppel, Simon C.; Su, Tao; Bogs, Jochen; Zu, Yuangang; An, Zhigang; Rausch, Thomas

    2013-01-01

    In Catharanthus roseus, the monoterpene moiety exerts a strong flux control for monoterpene indole alkaloid (MIA) formation. Monoterpene synthesis depends on the methyl-D-erythritol 4-phosphate (MEP) pathway. Here, we have explored the regulation of this pathway in response to developmental and environmental cues and in response to specific enzyme inhibitors. For the MEP pathway entry enzyme 1-deoxy-D-xylulose 5-phosphate synthase (DXS), a new (type I) DXS isoform, CrDXS1, has been cloned, which, in contrast to previous reports on type II CrDXS, was not transcriptionally activated by the transcription factor ORCA3. Regulation of the MEP pathway in response to metabolic perturbations has been explored using the enzyme inhibitors clomazone (precursor of 5-ketochlomazone, inhibitor of DXS) and fosmidomycin (inhibitor of deoxyxylulose 5-phosphate reductoisomerase (DXR)), respectively. Young leaves of non-flowering plants were exposed to both inhibitors, adopting a non-invasive in vivo technique. Transcripts and proteins of DXS (3 isoforms), DXR, and hydroxymethylbutenyl diphosphate synthase (HDS) were monitored, and protein stability was followed in isolated chloroplasts. Transcripts for DXS1 were repressed by both inhibitors, whereas transcripts for DXS2A&B, DXR and HDS increased after clomazone treatment but were barely affected by fosmidomycin treatment. DXS protein accumulated in response to both inhibitors, whereas DXR and HDS proteins were less affected. Fosmidomycin-induced accumulation of DXS protein indicated substantial posttranscriptional regulation. Furthermore, fosmidomycin effectively protected DXR against degradation in planta and in isolated chloroplasts. Thus our results suggest that DXR protein stability may be affected by substrate binding. In summary, the present results provide novel insight into the regulation of DXS expression in C. roseus in response to MEP-pathway perturbation. PMID:23650515