Sample records for active metabolite oseltamivir

  1. Population pharmacokinetics of oseltamivir and oseltamivir carboxylate in obese and non‐obese volunteers

    PubMed Central

    Chairat, Kalayanee; Jittamala, Podjanee; Hanpithakpong, Warunee; Day, Nicholas P. J.; White, Nicholas J.; Pukrittayakamee, Sasithon

    2016-01-01

    Aims The aims of the present study were to compare the pharmacokinetics of oseltamivir and its active antiviral metabolite oseltamivir carboxylate in obese and non‐obese individuals and to determine the effect of obesity on the pharmacokinetic properties of oseltamivir and oseltamivir carboxylate. Methods The population pharmacokinetic properties of oseltamivir and oseltamivir carboxylate were evaluated in 12 obese [body mass index (BMI) ≥30 kg m−2) and 12 non‐obese (BMI <30 kg m−2) Thai adult volunteers receiving a standard dose of 75 mg and a double dose of 150 mg in a randomized sequence. Concentration–time data were collected and analysed using nonlinear mixed‐effects modelling. Results The pharmacokinetics of oseltamivir and oseltamivir carboxylate were described simultaneously by first‐order absorption, with a one‐compartment disposition model for oseltamivir, followed by a metabolism compartment and a one‐compartment disposition model for oseltamivir carboxylate. Creatinine clearance was a significant predictor of oseltamivir carboxylate clearance {3.84% increase for each 10 ml min−1 increase in creatinine clearance [95% confidence interval (CI) 0.178%, 8.02%]}. Obese individuals had an approximately 25% (95% CI 24%, 28%) higher oseltamivir clearance, 20% higher oseltamivir volume of distribution (95% CI 19%, 23%) and 10% higher oseltamivir carboxylate clearance (95% CI 9%, 11%) compared with non‐obese individuals. However, these altered pharmacokinetic properties were small and did not change the overall exposure to oseltamivir carboxylate. Conclusions The results confirmed that a dose adjustment for oseltamivir in obese individuals is not necessary on the basis of its pharmacokinetics. PMID:26810861

  2. The anti-influenza drug oseltamivir evokes hypothermia in mice through dopamine D2 receptor activation via central actions.

    PubMed

    Fukushima, Akihiro; Fukui, Arisa; Takemura, Yuki; Maeda, Yasuhiro; Ono, Hideki

    2018-01-01

    Oseltamivir has a hypothermic effect in mice when injected intraperitoneally (i.p.) and intracerebroventricularly (i.c.v.). Here we show that the hypothermia evoked by i.c.v.-oseltamivir is inhibited by non-selective dopamine receptor antagonists (sulpiride and haloperidol) and the D 2 -selective antagonist L-741,626, but not by D 1 /D 5 -selective and D 3 -selective antagonists (SCH-23390 and SB-277011-A, respectively). The hypothermic effect of i.p.-administered oseltamivir was not inhibited by sulpiride, haloperidol, L-741,626 and SCH-23390. In addition, neither sulpiride, haloperidol nor SCH-23390 blocked hypothermia evoked by i.c.v.-administered oseltamivir carboxylate (a hydrolyzed metabolite of oseltamivir). These results suggest that oseltamivir in the brain induces hypothermia through activation of dopamine D 2 receptors. Copyright © 2018 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

  3. Reduction in sympathetic nerve activity as a possible mechanism for the hypothermic effect of oseltamivir, an anti-influenza virus drug, in normal mice.

    PubMed

    Ono, Hideki; Iwajima, Yui; Nagano, Yuko; Chazono, Kaori; Maeda, Yasuhiro; Ohsawa, Masahiro; Yamamoto, Shohei

    2013-07-01

    Oseltamivir, an anti-influenza virus drug, has strong antipyretic effects in mice (Biological and Pharmaceutical Bulletin, 31, 2008, 638) and patients with influenza. In addition, hypothermia has been reported as an adverse event. The prodrug oseltamivir is converted to oseltamivir carboxylate (OC), an active metabolite of influenza virus neuraminidase. In this study, core body temperature was measured in mice, and oseltamivir and OC were administered intracerebroventricularly (i.c.v.) or intraperitoneally (i.p). Low i.c.v. doses of oseltamivir and OC dose-dependently produced hypothermia. Zanamivir (i.c.v.), another neuraminidase inhibitor, did not produce hypothermia. These results suggested that the hypothermic effects of oseltamivir (i.p. and i.c.v.) and OC (i.c.v.) are not due to neuraminidase inhibition. OC (i.p.) did not lower body temperature. Although mecamylamine (i.c.v.) blocked the hypothermic effect of nicotine-administered i.c.v., the hypothermic effects of oseltamivir and OC (i.c.v.) were not blocked by mecamylamine (i.c.v.). The effect of oseltamivir (i.p.) was markedly increased by s.c.-pre-administered mecamylamine and also hexamethonium, a peripherally acting ganglionic blocker, suggesting their potentiating interaction at peripheral sites. The hypothermic effect of nicotine (i.c.v.) was decreased by lower doses of oseltamivir (i.c.v.), suggesting the anti-nicotinic action of oseltamivir. These results suggest that oseltamivir (i.p.) causes hypothermia through depression of sympathetic temperature regulatory mechanisms via inhibition of nicotinic receptor function and through unknown central mechanisms. © 2013 Nordic Pharmacological Society. Published by John Wiley & Sons Ltd.

  4. Comparison of Oseltamivir and Oseltamivir Carboxylate Concentrations in Venous Plasma, Venous Blood, and Capillary Blood in Healthy Volunteers

    PubMed Central

    Instiaty, Insti; Lindegardh, Niklas; Jittmala, Podjanee; Hanpithakpong, Warunee; Blessborn, Daniel; Pukrittayakamee, Sasithon; White, Nicholas J.

    2013-01-01

    Oseltamivir and oseltamivir carboxylate concentrations were measured in venous plasma, venous blood, and capillary blood taken simultaneously from 24 healthy volunteers. Median (range) venous-blood-to-plasma ratios were 1.42 (0.920 to 1.97) for oseltamivir and 0.673 (0.564 to 0.814) for oseltamivir carboxylate. Capillary blood/venous plasma ratios were 1.32 (0.737 to 3.16) for oseltamivir and 0.685 (0.502 to 1.34) for oseltamivir carboxylate. Oseltamivir concentrations in venous and capillary blood were similar. Oseltamivir carboxylate showed a time-dependent distribution between venous and capillary blood. PMID:23507284

  5. Potential adverse effects of oseltamivir in rats: males are more vulnerable than females.

    PubMed

    El-Sayed, Wael M; Al-Kahtani, Mohamed Ali

    2011-09-01

    Oseltamivir is the most widely used antiviral drug for the treatment and prophylaxis of influenza. However, not much is known about its adverse effects. The potential side effects were investigated in male and female rats (140-170 g). Oseltamivir was administered at 2.2 mg·kg(-1)·day(-1) for 5 days. For both genders, treatment with oseltamivir resulted in significant reductions in the hepatic activities of glutathione reductase, glutathione peroxidase, and glutathione S-transferase. Also for both genders, oseltamivir produced modest reductions in the hepatic activities of UDP-glucuronosyltransferase, quinone oxidoreductase, thioredoxin reductase, CYP1A1/2, and CYP3A, as well as hepatic glutathione content. For both genders, neither the kidney functions nor protein profile was affected by oseltamivir. Oseltamivir also caused significant elevation in serum levels of both triacylglycerols and LDL-cholesterol and in the activity of γ-glutamyl transpeptidase, in both genders. For male animals only, oseltamivir treatment elevated the serum level of total cholesterol as well as the activity of serum alanine aminotransferase, and reduced the hepatic activities of superoxide dismutase and catalase. Oseltamivir caused oxidative stress and acute toxicity in the liver, and disrupted the cholesterol and lipid metabolism but was less likely to cause serious drug interactions. There was a sexual differentiation in these adverse effects, with adverse effects being more evident in male rats.

  6. Inhibition of MAO-A and stimulation of behavioural activities in mice by the inactive prodrug form of the anti-influenza agent oseltamivir.

    PubMed

    Hiasa, Miki; Isoda, Yumiko; Kishimoto, Yasushi; Saitoh, Kenta; Kimura, Yasuaki; Kanai, Motomu; Shibasaki, Masakatsu; Hatakeyama, Dai; Kirino, Yutaka; Kuzuhara, Takashi

    2013-05-01

    Oseltamivir is the most widely prescribed anti-influenza medication. However, in rare instances, it has been reported to stimulate behavioural activities in adolescents. The goal of this study was to determine the molecular mechanism responsible for these behavioural activities. We performed an in vitro assay of MAO-A, the enzyme responsible for neurotransmitter degradation, using either the active form - oseltamivir carboxylate (OC) or the inactive prodrug - oseltamivir ethyl ester (OEE). We also analysed the docking of MAO-A with OEE or OC in silico. Mouse behaviours after OEE or OC administration were monitored using automated video and computer analysis. OEE, but not OC, competitively and selectively inhibited human MAO-A. The estimated Ki value was comparable with the Km values of native substrates of MAO-A. Docking simulations in silico based on the tertiary structure of MAO-A suggested that OEE could fit into the inner pocket of the enzyme. Behavioural monitoring using automated video analysis further revealed that OEE, not OC, significantly enhanced spontaneous behavioural activities in mice, such as jumping, rearing, sniffing, turning and walking. Our multilevel analyses suggested OEE to be the cause of the side effects associated with oseltamivir and revealed the molecular mechanism underlying the stimulated behaviours induced by oseltamivir in some circumstances. © 2013 The Authors. British Journal of Pharmacology © 2013 The British Pharmacological Society.

  7. Inhibition of MAO-A and stimulation of behavioural activities in mice by the inactive prodrug form of the anti-influenza agent oseltamivir

    PubMed Central

    Hiasa, Miki; Isoda, Yumiko; Kishimoto, Yasushi; Saitoh, Kenta; Kimura, Yasuaki; Kanai, Motomu; Shibasaki, Masakatsu; Hatakeyama, Dai; Kirino, Yutaka; Kuzuhara, Takashi

    2013-01-01

    Background and Purpose Oseltamivir is the most widely prescribed anti-influenza medication. However, in rare instances, it has been reported to stimulate behavioural activities in adolescents. The goal of this study was to determine the molecular mechanism responsible for these behavioural activities. Experimental Approach We performed an in vitro assay of MAO-A, the enzyme responsible for neurotransmitter degradation, using either the active form – oseltamivir carboxylate (OC) or the inactive prodrug – oseltamivir ethyl ester (OEE). We also analysed the docking of MAO-A with OEE or OC in silico. Mouse behaviours after OEE or OC administration were monitored using automated video and computer analysis. Key Results OEE, but not OC, competitively and selectively inhibited human MAO-A. The estimated Ki value was comparable with the Km values of native substrates of MAO-A. Docking simulations in silico based on the tertiary structure of MAO-A suggested that OEE could fit into the inner pocket of the enzyme. Behavioural monitoring using automated video analysis further revealed that OEE, not OC, significantly enhanced spontaneous behavioural activities in mice, such as jumping, rearing, sniffing, turning and walking. Conclusions and Implications Our multilevel analyses suggested OEE to be the cause of the side effects associated with oseltamivir and revealed the molecular mechanism underlying the stimulated behaviours induced by oseltamivir in some circumstances. PMID:23320399

  8. Compliance to Oseltamivir among Two Populations in Oxfordshire, United Kingdom Affected by Influenza A(H1N1)pdm09, November 2009 – A Waste Water Epidemiology Study

    PubMed Central

    Singer, Andrew C.; Järhult, Josef D.; Grabic, Roman; Khan, Ghazanfar A.; Fedorova, Ganna; Fick, Jerker; Lindberg, Richard H.; Bowes, Michael J.; Olsen, Björn; Söderström, Hanna

    2013-01-01

    Antiviral provision remains the focus of many pandemic preparedness plans, however, there is considerable uncertainty regarding antiviral compliance rates. Here we employ a waste water epidemiology approach to estimate oseltamivir (Tamiflu®) compliance. Oseltamivir carboxylate (oseltamivir's active metabolite) was recovered from two waste water treatment plant (WWTP) catchments within the United Kingdom at the peak of the autumnal wave of the 2009 Influenza A (H1N1)pdm09 pandemic. Predictions of oseltamivir consumption from detected levels were compared with two sources of national government statistics to derive compliance rates. Scenario and sensitivity analysis indicated between 3–4 and 120–154 people were using oseltamivir during the study period in the two WWTP catchments and a compliance rate between 45–60%. With approximately half the collected antivirals going unused, there is a clear need to alter public health messages to improve compliance. We argue that a near real-time understanding of drug compliance at the scale of the waste water treatment plant (hundreds to millions of people) can potentially help public health messages become more timely, targeted, and demographically sensitive, while potentially leading to less mis- and un-used antiviral, less wastage and ultimately a more robust and efficacious pandemic preparedness plan. PMID:23613721

  9. Pacific region influenza surveillance for oseltamivir resistance.

    PubMed

    Miller, Heather B; Gose, Remedios B; Nagata, Mark T; Sciulli, Rebecca H; Whelen, A Christian

    2012-05-01

    Hawaii and the United States-affiliated Pacific islands (USAPI) host over 8 million travelers annually, most of whom originate in Asia, Australia, and the Americas where prevalence of oseltamivir resistance in 2009 pandemic influenza A (H1N1) has been reported to be 2.5-3.5%. To survey a collection of samples from Hawaii and the USAPI that had tested positive for the 2009 pandemic influenza A (H1N1) virus by RTI-PCR to assess whether antiviral resistance emerged in these island communities during the 2009 H1N1 pandemic. We examined RNA extracted from Hawaiian and USAPI cases for the neuraminidase H275Y mutation associated with oseltamivir resistance by pyrosequencing. Two hundred and sixty-three (263) 2009 pandemic influenza A (H1N1) positive specimens were tested and 263/263 (100%) were shown to lack the mutation most commonly associated with oseltamivir resistance. There was no evidence of oseltamivir resistant A(H1N1)pdm09 virus during the 2009 pandemic in the Pacific islands despite considerable travel exposure. Geographic isolation, the lack of a "second wave" of pandemic influenza, judicious antiviral use, aggressive vaccination, and below average tourism due to the global economic crisis may have been contributing factors. Continued surveillance and vigilance is necessary to monitor unpredictable influenza activity. Copyright © 2012 Elsevier B.V. All rights reserved.

  10. Oseltamivir- related psychiatric manifestations.

    PubMed

    Guisado-Macías, Juan A; Rodríguez, Francisco F; Méndez-Sánchez, Fabiola; Bolívar-Perálvarez, Moisés

    2012-01-01

    The importance effect on the population of the new virus Influenza A/H1N1 and the potential therapeutic with Oseltamivir. Clinical case. Patient of 62 years old, without history of interest, contracted Influeza A, that she undergoes a confusional syndrome responding to antipsychotics and with complete recovery after the episode. Conclusions. Establish the possible relationship between the various factors are influencing the onset confusional syndrome in a patient infected with Inluenza A treated with Oseltamivir.

  11. Published sequences do not support transfer of oseltamivir resistance mutations from avian to human influenza A virus strains.

    PubMed

    Norberg, Peter; Lindh, Magnus; Olofsson, Sigvard

    2015-03-28

    Tamiflu (oseltamivir phosphate ester, OE) is a widely used antiviral active against influenza A virus. Its active metabolite, oseltamivir carboxylate (OC), is chemically stable and secreted into wastewater treatment plants. OC contamination of natural habitats of waterfowl might induce OC resistance in influenza viruses persistently infecting waterfowl, and lead to transfer of OC-resistance from avian to human influenza. The aim of this study was to evaluate whether such has occurred. A genomics approach including phylogenetic analysis and probability calculations for homologous recombination was applied on altogether 19,755 neuraminidase (N1 and N2) genes from virus sampled in humans and birds, with and without resistance mutations. No evidence for transfer of OE resistance mutations from avian to human N genes was obtained, and events suggesting recombination between human and avian influenza virus variants could not be traced in the sequence material studied. The results indicate that resistance in influenza viruses infecting humans is due to the selection pressure posed by the global OE administration in humans rather than transfer from avian influenza A virus strains carrying mutations induced by environmental exposure to OC.

  12. Oseltamivir and indomethacin reduce the oxidative stress in brain and stomach of infected rats.

    PubMed

    Guzmán, David Calderón; Herrera, Maribel Ortiz; Brizuela, Norma Osnaya; Mejía, Gerardo Barragán; García, Ernestina Hernández; Olguín, Hugo Juárez; Ruíz, Norma Labra; Peraza, Armando Valenzuela

    2018-02-01

    The aim of this study was to determine the effect of oseltamivir and indomethacin on lipid peroxidation (LP), GABA levels, and ATPase activity in brain and stomach of normal and infected rats (IR), as novel inflammation model. Female Sprague Dawley rats grouped five each, either in the absence or presence of a live culture of Salmonella typhimurium (S. typh), were treated as follows: group 1 (control), PBS buffer; group 2, oseltamivir (100 mg/kg); group 3, indomethacin (67 μg/rat); group 4, oseltamivir (100 mg/kg) + indomethacin (67 μg/rat). All drugs were given intraperitoneally for 5 days. IR received the same treatments and the brain and stomach of the rats were removed in order to measure levels of GABA, LP, and total ATPase, using validated methods. Levels of GABA increased in stomach and cortex of IR with oseltamivir, but decreased in striatum and cerebellum/medulla oblongata of IR with indomethacin. LP decreased in the three brain regions of IR with oseltamivir. ATPase increased in stomach of IR and non-IR with oseltamivir and in striatum and cerebellum/medulla oblongata of IR with indomethacin. Results suggest that the effect of free radicals produced in an infection and inflammatory condition caused by S. typh could be less toxic by a combination of oseltamivir and indomethacin. © 2017 APMIS. Published by John Wiley & Sons Ltd.

  13. Debate Regarding Oseltamivir Use for Seasonal and Pandemic Influenza

    PubMed Central

    Kelly, Heath

    2016-01-01

    A debate about the market-leading influenza antiviral medication, oseltamivir, which initially focused on treatment for generally mild illness, has been expanded to question the wisdom of stockpiling for use in future influenza pandemics. Although randomized controlled trial evidence confirms that oseltamivir will reduce symptom duration by 17–25 hours among otherwise healthy adolescents and adults with community-managed disease, no randomized controlled trials have examined the effectiveness of oseltamivir against more serious outcomes. Observational studies, although criticized on methodologic grounds, suggest that oseltamivir given early can reduce the risk for death by half among persons hospitalized with confirmed infection caused by influenza A(H1N1)pdm09 and influenza A(H5N1) viruses. However, available randomized controlled trial data may not be able to capture the effect of oseltamivir use among hospitalized patients with severe disease. We assert that data on outpatients with relatively mild disease should not form the basis for policies on the management of more severe disease. PMID:27191818

  14. Oseltamivir use and outcomes during the 2009 influenza A H1N1 pandemic in Taiwan

    PubMed Central

    2013-01-01

    Background The Taiwan CDC provided free oseltamivir to all patients with influenza infections confirmed by rapid testing or who had clinical warning symptoms during the 2009 H1N1 influenza pandemic in Taiwan. However, oseltamivir utilization patterns, cost, and outcomes among oseltamivir-treated patients remained unclear. Method A population-level, observational cohort study was conducted using the Taiwan National Health Insurance Database from January to December 2009 to describe the use of oseltamivir. Result Prescription trend over weeks increased after a change in government policy and responded to the influenza virus activity. The overall prescription rate was 22.33 per 1000 persons, with the highest prescription rate of 116.5 for those aged 7–12 years, followed by 69.0 for those aged 13–18 years, while the lowest rate was 1.7 for those aged ≥ 65 years. As influenza virus activity increased, the number of prescriptions for those aged ≤18 years rose significantly, whereas no substantial change was observed for those aged ≥65 years. There were also regional variations in terms of oseltamivir utilization and influenza complication rates. Conclusions Oseltamivir was widely used in the 2009 H1N1 influenza pandemic in Taiwan, particularly in those aged 7–18 years. The number of prescriptions for oseltamivir increased with a change in government policy and with increasing cases of pandemic influenza. Further study is needed to examine whether there is an over- or under-use of anti-influenza drugs in different age groups or regions and to examine the current policy of public use of anti-influenza drugs to reduce influenza-associated morbidity and mortality. PMID:23849163

  15. Chemical stability of oseltamivir in oral solutions.

    PubMed

    Albert, K; Bockshorn, J

    2007-09-01

    The stability of oseltamivir in oral aqueous solutions containing the preservative sodium benzoate was studied by a stability indicating HPLC-method. The separation was achieved on a RP-18 ec column using a gradient of mobile phase A (aqueous solution of 50 mM ammonium acetate) and mobile phase B (60% (v/v) acetonitrile/40% (v/v) mobile phase A). The assay was subsequently validated according to the ICH guideline Q2(R1). The extemporaneously prepared "Oseltamivir Oral Solution 15 mg/ml for Adults or for Children" (NRF 31.2.) according to the German National Formulary ("Neues Rezeptur-Formularium") was stable for 84 days if stored under refrigeration. After storage at 25 degrees C the content of oseltamivir decreased to 98.4%. Considering the toxicological limit of 0.5% of the 5-acetylamino derivative (the so-called isomer I) the solution is stable for 46 days. Oseltamivir was less stable in a solution prepared with potable water instead of purified water. Due to an increasing pH the stability of this solution decreased to 14 days. Furthermore a white precipitate of mainly calcium phosphate was observed. The addition of 0.1% anhydrous citric acid avoided these problems and improved the stability of the solution prepared with potable water to 63 days. Sodium benzoate was stable in all oral solutions tested.

  16. Environmental Levels of the Antiviral Oseltamivir Induce Development of Resistance Mutation H274Y in Influenza A/H1N1 Virus in Mallards

    PubMed Central

    Järhult, Josef D.; Söderström, Hanna; Orozovic, Goran; Gunnarsson, Gunnar; Bröjer, Caroline; Latorre-Margalef, Neus; Fick, Jerker; Grabic, Roman; Lennerstrand, Johan; Waldenström, Jonas; Lundkvist, Åke; Olsen, Björn

    2011-01-01

    Oseltamivir (Tamiflu®) is the most widely used drug against influenza infections and is extensively stockpiled worldwide as part of pandemic preparedness plans. However, resistance is a growing problem and in 2008–2009, seasonal human influenza A/H1N1 virus strains in most parts of the world carried the mutation H274Y in the neuraminidase gene which causes resistance to the drug. The active metabolite of oseltamivir, oseltamivir carboxylate (OC), is poorly degraded in sewage treatment plants and surface water and has been detected in aquatic environments where the natural influenza reservoir, dabbling ducks, can be exposed to the substance. To assess if resistance can develop under these circumstances, we infected mallards with influenza A/H1N1 virus and exposed the birds to 80 ng/L, 1 µg/L and 80 µg/L of OC through their sole water source. By sequencing the neuraminidase gene from fecal samples, we found that H274Y occurred at 1 µg/L of OC and rapidly dominated the viral population at 80 µg/L. IC50 for OC was increased from 2–4 nM in wild-type viruses to 400–700 nM in H274Y mutants as measured by a neuraminidase inhibition assay. This is consistent with the decrease in sensitivity to OC that has been noted among human clinical isolates carrying H274Y. Environmental OC levels have been measured to 58–293 ng/L during seasonal outbreaks and are expected to reach µg/L-levels during pandemics. Thus, resistance could be induced in influenza viruses circulating among wild ducks. As influenza viruses can cross species barriers, oseltamivir resistance could spread to human-adapted strains with pandemic potential disabling oseltamivir, a cornerstone in pandemic preparedness planning. We propose surveillance in wild birds as a measure to understand the resistance situation in nature and to monitor it over time. Strategies to lower environmental levels of OC include improved sewage treatment and, more importantly, a prudent use of antivirals. PMID:21931841

  17. Oseltamivir Treatment for Children with Influenza-Like Illness in China: A Cost-Effectiveness Analysis.

    PubMed

    Shen, Kunling; Xiong, Tengbin; Tan, Seng Chuen; Wu, Jiuhong

    2016-01-01

    Influenza is a common viral respiratory infection that causes epidemics and pandemics in the human population. Oseltamivir is a neuraminidase inhibitor-a new class of antiviral therapy for influenza. Although its efficacy and safety have been established, there is uncertainty regarding whether influenza-like illness (ILI) in children is best managed by oseltamivir at the onset of illness, and its cost-effectiveness in children has not been studied in China. To evaluate the cost-effectiveness of post rapid influenza diagnostic test (RIDT) treatment with oseltamivir and empiric treatment with oseltamivir comparing with no antiviral therapy against influenza for children with ILI. We developed a decision-analytic model based on previously published evidence to simulate and evaluate 1-year potential clinical and economic outcomes associated with three managing strategies for children presenting with symptoms of influenza. Model inputs were derived from literature and expert opinion of clinical practice and research in China. Outcome measures included costs and quality-adjusted life year (QALY). All the interventions were compared with incremental cost-effectiveness ratios (ICER). In base case analysis, empiric treatment with oseltamivir consistently produced the greatest gains in QALY. When compared with no antiviral therapy, the empiric treatment with oseltamivir strategy is very cost effective with an ICER of RMB 4,438. When compared with the post RIDT treatment with oseltamivir, the empiric treatment with oseltamivir strategy is dominant. Probabilistic sensitivity analysis projected that there is a 100% probability that empiric oseltamivir treatment would be considered as a very cost-effective strategy compared to the no antiviral therapy, according to the WHO recommendations for cost-effectiveness thresholds. The same was concluded with 99% probability for empiric oseltamivir treatment being a very cost-effective strategy compared to the post RIDT treatment with

  18. Coadministration of Hedera helix L. Extract Enabled Mice to Overcome Insufficient Protection against Influenza A/PR/8 Virus Infection under Suboptimal Treatment with Oseltamivir

    PubMed Central

    Shim, Aeri; Lee, Bo-Ra; Kwon, Bo-Eun; Song, Hyuk-Hwan; Kim, Yeon-Jeong; Chang, Sun-Young; Jeong, Hyeon Gun; Kim, Jong Geal; Seo, Sang-Uk; Kim, HyunPyo; Kwon, YongSoo; Ko, Hyun-Jeong

    2015-01-01

    Several anti-influenza drugs that reduce disease manifestation exist, and although these drugs provide clinical benefits in infected patients, their efficacy is limited by the emergence of drug-resistant influenza viruses. In the current study, we assessed the therapeutic strategy of enhancing the antiviral efficacy of an existing neuraminidase inhibitor, oseltamivir, by coadministering with the leaf extract from Hedera helix L, commonly known as ivy. Ivy extract has anti-inflammatory, antibacterial, antifungal, and antihelminthic properties. In the present study, we investigated its potential antiviral properties against influenza A/PR/8 (PR8) virus in a mouse model with suboptimal oseltamivir that mimics a poor clinical response to antiviral drug treatment. Suboptimal oseltamivir resulted in insufficient protection against PR8 infection. Oral administration of ivy extract with suboptimal oseltamivir increased the antiviral activity of oseltamivir. Ivy extract and its compounds, particularly hedrasaponin F, significantly reduced the cytopathic effect in PR8-infected A549 cells in the presence of oseltamivir. Compared with oseltamivir treatment alone, coadministration of the fraction of ivy extract that contained the highest proportion of hedrasaponin F with oseltamivir decreased pulmonary inflammation in PR8-infected mice. Inflammatory cytokines and chemokines, including tumor necrosis factor-alpha and chemokine (C-C motif) ligand 2, were reduced by treatment with oseltamivir and the fraction of ivy extract. Analysis of inflammatory cell infiltration in the bronchial alveolar of PR8-infected mice revealed that CD11b+Ly6G+ and CD11b+Ly6Cint cells were recruited after virus infection; coadministration of the ivy extract fraction with oseltamivir reduced infiltration of these inflammatory cells. In a model of suboptimal oseltamivir treatment, coadministration of ivy extract fraction that includes hedrasaponin F increased protection against PR8 infection that could be

  19. Coadministration of Hedera helix L. Extract Enabled Mice to Overcome Insufficient Protection against Influenza A/PR/8 Virus Infection under Suboptimal Treatment with Oseltamivir.

    PubMed

    Hong, Eun-Hye; Song, Jae-Hyoung; Shim, Aeri; Lee, Bo-Ra; Kwon, Bo-Eun; Song, Hyuk-Hwan; Kim, Yeon-Jeong; Chang, Sun-Young; Jeong, Hyeon Gun; Kim, Jong Geal; Seo, Sang-Uk; Kim, HyunPyo; Kwon, YongSoo; Ko, Hyun-Jeong

    2015-01-01

    Several anti-influenza drugs that reduce disease manifestation exist, and although these drugs provide clinical benefits in infected patients, their efficacy is limited by the emergence of drug-resistant influenza viruses. In the current study, we assessed the therapeutic strategy of enhancing the antiviral efficacy of an existing neuraminidase inhibitor, oseltamivir, by coadministering with the leaf extract from Hedera helix L, commonly known as ivy. Ivy extract has anti-inflammatory, antibacterial, antifungal, and antihelminthic properties. In the present study, we investigated its potential antiviral properties against influenza A/PR/8 (PR8) virus in a mouse model with suboptimal oseltamivir that mimics a poor clinical response to antiviral drug treatment. Suboptimal oseltamivir resulted in insufficient protection against PR8 infection. Oral administration of ivy extract with suboptimal oseltamivir increased the antiviral activity of oseltamivir. Ivy extract and its compounds, particularly hedrasaponin F, significantly reduced the cytopathic effect in PR8-infected A549 cells in the presence of oseltamivir. Compared with oseltamivir treatment alone, coadministration of the fraction of ivy extract that contained the highest proportion of hedrasaponin F with oseltamivir decreased pulmonary inflammation in PR8-infected mice. Inflammatory cytokines and chemokines, including tumor necrosis factor-alpha and chemokine (C-C motif) ligand 2, were reduced by treatment with oseltamivir and the fraction of ivy extract. Analysis of inflammatory cell infiltration in the bronchial alveolar of PR8-infected mice revealed that CD11b+Ly6G+ and CD11b+Ly6Cint cells were recruited after virus infection; coadministration of the ivy extract fraction with oseltamivir reduced infiltration of these inflammatory cells. In a model of suboptimal oseltamivir treatment, coadministration of ivy extract fraction that includes hedrasaponin F increased protection against PR8 infection that could be

  20. The mechanisms of sudden-onset type adverse reactions to oseltamivir.

    PubMed

    Hama, R; Bennett, C L

    2017-02-01

    Oseltamivir is contraindicated for people aged 10-19 in principle in Japan, due to concern about abnormal behaviours. Sudden death is another concern. This review examines growing evidence of their association and discusses underlying mechanisms of these sudden-onset type reactions to oseltamivir. First, the importance of animal models and the concept of human equivalent dose (HED) is summarized. Second, the specific condition for oseltamivir use, influenza infection, is reviewed. Third, findings from toxicity studies conducted prior to and after the marketing of oseltamivir are reported on to provide context on the observation of a possible causal association. Fourth, similarity and consistency of toxicity in humans with that in other animals is described. Finally, coherence of toxicokinetic and molecular level of evidence (channels, receptors and enzymes), including differences from the toxicity of other neuraminidase inhibitors, is reviewed. It is concluded that unchanged oseltamivir has various effects on the central nervous system (CNS) that may be related to clinical findings including hypothermia, abnormal behaviours including with fatal outcome, and sudden death. Among receptors and enzymes related to CNS action, it is known that oseltamivir inhibits nicotinic acetylcholine receptors, which are closely related to hypothermia, as well as human monoamine oxidase-A (MAO-A), which is closely related to abnormal or excitatory behaviours. Receptors such as GABA A , GABA B and NMDA and their related receptors/channels including Na + and Ca 2+ channels are thought to be other candidates for investigation related to respiratory suppression followed by sudden death and psychotic reactions (both acute and chronic), respectively. © 2016 The Authors. Acta Neurologica Scandinavica Published by John Wiley & Sons Ltd.

  1. Oseltamivir-resistant pandemic influenza a (H1N1) 2009 viruses in Spain.

    PubMed

    Ledesma, Juan; Vicente, Diego; Pozo, Francisco; Cilla, Gustavo; Castro, Sonia Pérez; Fernández, Jonathan Suárez; Ruiz, Mercedes Pérez; Navarro, José María; Galán, Juan Carlos; Fernández, Mirian; Reina, Jordi; Larrauri, Amparo; Cuevas, María Teresa; Casas, Inmaculada; Breña, Pilar Pérez

    2011-07-01

    Pandemic influenza A (H1N1) 2009 virus appeared in Spain on April 25, 2009 for the first time. This new virus was adamantane-resistant but it was sensitive to neuraminidase (NA) inhibitors oseltamivir and zanamivir. To detect oseltamivir-resistant pandemic influenza A (H1N1) 2009 viruses by the Spanish Influenza Surveillance System (SISS) and a possible spread of oseltamivir-resistant viruses in Spain since starting of the pandemic situation. A total of 1229 respiratory samples taken from 413 severe and 766 non-severe patients with confirmed viral detection of pandemic influenza A (H1N1) 2009 viruses from different Spanish regions were analyzed for the specific detection of the H275Y mutation in NA between April 2009 and May 2010. H275Y NA substitution was found in 8 patients infected with pandemic influenza A (H1N1) 2009 viruses collected in November and December 2009 and in January 2010. All oseltamivir-resistant viruses were detected in severe patients (8/413, 1.93%) who previously received treatment with oseltamivir. Six of these patients were immunocompromised. In Spain, the number of oseltamivir-resistant pandemic influenza A (H1N1) 2009 viruses is until now very low. No evidence for any spread of oseltamivir-resistant H1N1 viruses is achieved in our Country. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. Oseltamivir Pharmacokinetics, Dosing, and Resistance Among Children Aged <2 Years With Influenza

    PubMed Central

    Kimberlin, David W.; Acosta, Edward P.; Prichard, Mark N.; Sánchez, Pablo J.; Ampofo, Krow; Lang, David; Ashouri, Negar; Vanchiere, John A.; Abzug, Mark J.; Abughali, Nazha; Caserta, Mary T.; Englund, Janet A.; Sood, Sunil K.; Spigarelli, Michael G.; Bradley, John S.; Lew, Judy; Michaels, Marian G.; Wan, Wen; Cloud, Gretchen; Jester, Penelope; Lakeman, Fred D.; Whitley, Richard J.; Giles, Dusty; Cotton, Bari; Judy, Sharon; Cowie, Margaret; Francis, Jeanne; Evans, Candice; O'Donnell, Nan; Shiraishi, Ofelia Vargas; Latiolais, Lisa; Aymami, Valeri; Dole, Ken; Gaultier, Julie; Lofthus, Gerry; Kinnunen, Diane; Lacombe, Kirsten; Stellato, Nancy; Denlinger, Julie; Hingtgen, Sara; Mason, Christina; Jeffrey, Noreen

    2013-01-01

    Background. Children <2 years of age are at high risk of influenza-related mortality and morbidity. However, the appropriate dose of oseltamivir for children <2 years of age is unknown. Methods. The National Institute of Allergy and Infectious Diseases Collaborative Antiviral Study Group evaluated oseltamivir in infants aged <2 years in an age–de-escalation, adaptive design with a targeted systemic exposure. Results. From 2006 to 2010, 87 subjects enrolled. An oseltamivir dose of 3.0 mg/kg produced drug exposures within the target range in subjects 0–8 months of age, although there was a greater degree of variability in infants <3 months of age. In subjects 9–11 months of age, a dose of 3.5 mg/kg produced drug exposures within the target range. Six of 10 subjects aged 12–23 months receiving the Food and Drug Administration–approved unit dose for this age group (ie, 30 mg) had oseltamivir carboxylate exposures below the target range. Virus from 3 subjects developed oseltamivir resistance during antiviral treatment. Conclusions. The appropriate twice-daily oral oseltamivir dose for infants ≤8 months of age is 3.0 mg/kg, while the dose for infants 9–11 months old is 3.5 mg/kg. Clinical Trials Registration. NCT00391768. PMID:23230059

  3. Immunological effects of the orally administered neuraminidase inhibitor oseltamivir in influenza virus-infected and uninfected mice.

    PubMed

    Burger, R A; Billingsley, J L; Huffman, J H; Bailey, K W; Kim, C U; Sidwell, R W

    2000-04-01

    Oseltamivir (GS4104), the ethyl ester prodrug of the carbocyclic transition state sialic acid analog GS4071, has been reported to be a striking inhibitor of influenza A and B virus infections in mice and ferrets. Multiple studies indicate this material to also be active against the disease in humans, and it has recently been approved for human use. The effect of oral gavage (p.o.) therapy of oseltamivir on various immune factors considered to be of importance in primary influenza virus infection was studied in mice. Both uninfected animals and those infected with influenza A/NWS/33 (H1N1) virus were used. Doses of 100 mg kg(-1) day(-1) were administered twice daily for 5 days beginning 16 h pre-virus exposure. Two hours after end of treatment, the mice were killed and their spleens assayed for cytotoxic T lymphocyte (CTL) and natural killer (NK) cell activity. Subpopulations of splenic T, T-helper, T-cytotoxic and B lymphocytes as well as macrophages were determined using flow cytometry. Similar significant (P<0.01) increases in CTL activity were seen at effector:target cell ratios of 60:1 and 30:1 in the infected mice treated with oseltamivir or with placebo. NK cell activity was greater in the infected mice than in uninfected mice; the levels in all animals were not significantly affected by treatment with oseltamivir. Macrophage, T, T-helper, T-cytotoxic and B lymphocyte populations were similar in both treated and untreated animals. These data indicate treatment with oseltamivir does not adversely affect the primary in vivo cellular immune responses to influenza virus infection assayed in this study. The experiment was repeated to show that treatment with this compound significantly prevented the development of the infection and inhibited virus titers in the lung. Surviving treated mice on day 21 had mean neutralizing antibody titers of 1:208, and withstood rechallenge with the virus at this time, indicating the initial virus-inhibitory effect also did not

  4. Effect of oseltamivir, zanamivir or oseltamivir-zanamivir combination treatments on transmission of influenza in households.

    PubMed

    Carrat, Fabrice; Duval, Xavier; Tubach, Florence; Mosnier, Anne; Van der Werf, Sylvie; Tibi, Annick; Blanchon, Thierry; Leport, Catherine; Flahault, Antoine; Mentré, France

    2012-01-01

    The effectiveness of neuraminidase inhibitors to reduce transmission when used as treatment in influenza-infected patients remains debated. In a prespecified analysis of a blinded randomized controlled trial on the efficacy of oseltamivir-zanamivir combination therapy versus oseltamivir and zanamivir monotherapy conducted during the 2008-2009 seasonal influenza epidemic, we compared the rate of secondary illness in household contacts of influenza-positive index patients between arms. Secondary illness was defined as occurrence in contacts of fever plus cough within 7 days from randomization of index patients. Analyses were conducted according to the delay between patients' onset of symptoms and intervention. A total of 543 household contacts of 267 index patients were included, of which 466 had follow-up assessment. A secondary illness was reported in 58 (12.5%) contacts with no significant difference between arms overall (P=0.07). When the analysis was limited to the 232 contacts of 136 index patients with first treatment intake within 24 h of onset of symptoms, a lower rate of secondary illness was reported in the combination therapy arm (2 of 56 [4%]) than in the oseltamivir arm (14 of 81 [17%]; P=0.014) and the zanamivir arm (14 of 95 [15%]; P=0.031). Multivariate analysis accounting for intra-household correlation confirmed these findings. Our analysis suggests a greater effectiveness of the combination therapy to reduce transmissibility when given to the index patient within 24 h of onset of symptoms. As the finding was obtained from a subgroup analysis, it should be interpreted with caution.

  5. The environmental fate of the antiviral drug oseltamivir carboxylate in different waters.

    PubMed

    Bartels, Peter; von Tümpling, Wolf

    2008-11-01

    Since the efficacy of oseltamivir carboxylate (OC) as the active metabolite of Tamiflu has been demonstrated against influenza viruses and even against the avian influenza virus (H5N1), millions of Tamiflu treatment courses are stockpiled worldwide. This was done not at least to follow the recommendations of the World Health Organization (WHO) to cope with a viral influenza pandemic. Concentrations up to 26-32 microg l(-1) OC in river catchment areas in the United States and in the United Kingdom had been predicted recently for a pandemic case, assuming an apparent persistence of the Tamiflu metabolite. Such concentrations may involve the risk of generation of antiviral resistance. But there is still a lack of data concerning the stability of OC in a surface water environment. Under this aspect these predictions have to be validated with concrete facts about the environmental fate of OC. In this article we summarized the results of three different daylight exposure experiments with OC in different waters under sterile and non-sterile conditions simulating shallow water processes at the latitude of approximately 52 degrees N. Using a river water solution containing 50 microg l(-1) OC under non-sterile conditions a half-life time of 17.8 days was observed. Direct photolysis plays no or only a negligible role for the decomposition of OC. Degradation of OC seems to occur as a combination of microbial metabolism and indirect photolysis.

  6. Effects of oseltamivir on influenza-related complications in children with chronic medical conditions.

    PubMed

    Piedra, Pedro A; Schulman, Kathy L; Blumentals, William A

    2009-07-01

    This study investigated the influence of oseltamivir on influenza-related complications and hospitalizations for children and adolescents, 1 to 17 years of age, with chronic medical conditions or neurologic or neuromuscular disease. In a retrospective study, outcomes for patients who were given oseltamivir within 1 day after influenza diagnosis were compared with those for patients who received no antiviral therapy. Anonymous data from MarketScan databases (Thomson Reuters, Cambridge, MA) were used to identify patients from 6 influenza seasons between 2000 and 2006. The study outcomes were frequencies of pneumonia, respiratory illnesses other than pneumonia, otitis media, and hospitalization. Oseltamivir was prescribed for 1634 patients according to the study criteria, and 3721 patients received no antiviral therapy for their influenza. After adjustment for demographic and medical history variables, oseltamivir was associated with significant reductions in the risks of respiratory illnesses other than pneumonia, otitis media and its complications, and all-cause hospitalization in the 14 days after influenza diagnosis. Analyses for 30 days after influenza diagnosis also showed significant risk reductions for respiratory illnesses other than pneumonia, otitis media and its complications, and all-cause hospitalization with oseltamivir. When it was prescribed at influenza diagnosis, oseltamivir was associated with reduced risks of influenza-related complications and hospitalizations for children and adolescents at high risk of influenza complications.

  7. The mechanisms of delayed onset type adverse reactions to oseltamivir

    PubMed Central

    Hama, Rokuro

    2016-01-01

    Abstract Oseltamivir is recommended for the treatment and prophylaxis of influenza in persons at higher risk for influenza complications such as individuals with diabetes, neuropsychiatric illnesses, and respiratory, cardiac, renal, hepatic or haematological diseases. However, a recent Cochrane review reported that reduction of antibody production, renal disorders, hyperglycaemia, psychiatric disorders, and QT prolongation may be related to oseltamivir use. The underlying mechanisms are reviewed. There is decisive evidence that administration of a clinically compatible dose of oseltamivir in mice challenged by a respiratory syncytial virus (RSV) that lacks a neuraminidase gene showed symptom-relieving effects and inhibition of viral clearance. These effects were accompanied by decreased level of T cell surface sialoglycosphingolipid (ganglioside) GM1 that is regulated by the endogenous neuraminidase in response to viral challenge. Clinical and non-clinical evidence supports the view that the usual dose of oseltamivir suppresses pro-inflammatory cytokines such as interferon-gamma, interleukin-6, and tumour necrosis factor-alpha almost completely with partial suppression of viral shedding in human influenza virus infection experiment. Animal toxicity tests support the clinical evidence with regard to renal and cardiac disorders (bradycardia and QT prolongation) and do not disprove the metabolic effect. Reduction of antibody production and cytokine induction and renal, metabolic, cardiac, and prolonged psychiatric disorders after oseltamivir use may be related to inhibition of the host’s endogenous neuraminidase. While the usual clinical dose of zanamivir may not have this effect, a higher dose or prolonged administration of zanamivir and other neuraminidase inhibitors may induce similar delayed reactions, including reduction of the antibody and/or cytokine production. PMID:27251370

  8. Prevalence of Influenza A(H1N1)pdm09 Virus Resistant to Oseltamivir in Shiraz, Iran, During 2012 - 2013.

    PubMed

    Khodadad, Nastaran; Moattari, Afagh; Shamsi Shahr Abadi, Mahmoud; Kadivar, Mohammad Rahim; Sarvari, Jamal; Tavakoli, Forough; Pirbonyeh, Neda; Emami, Amir

    2015-08-01

    Oseltamivir has been used as a drug of choice for the prophylaxis and treatment of human influenza A(H1N1)pdm09 infection across the world. However, the most frequently identified oseltamivir resistant virus, influenza A(H1N1)pdm09, exhibit the H275Y substitution in NA gene. This study aimed to determine the prevalence and phylogenetic relationships of oseltamivir resistance in influenza A(H1N1)pdm09 viruses isolated in Shiraz, Iran. Throat swab samples were collected from 200 patients with influenza-like disease from December 2012 until February 2013. A total of 77 influenza A(H1N1)pdm09 positive strains were identified by real-time polymerase chain reaction (PCR). Oseltamivir resistance was detected using quantal assay and nested-PCR method. The NA gene sequencing was conducted to detect oseltamivir-resistant mutants and establish the phylogeny of the prevalent influenza variants. Our results revealed that A(H1N1)pdm09 viruses present in these samples were susceptible to oseltamivir, and contained 5 site specific mutations (V13G, V106I, V241I, N248D, and N369K) in NA gene. These mutations correlated with increasing expression and enzymatic activity of NA protein in the influenza A(H1N1)pdm09 viruses, which were closely related to a main influenza A(H1N1)pdm09 cluster isolated around the world. A(H1N1)pdm09 viruses, identified in this study in Shiraz, Iran, contained 5 site specific mutations and were susceptible to oseltamivir.

  9. Peramivir is as effective as oral oseltamivir in the treatment of severe seasonal influenza.

    PubMed

    Yoo, Jung-Wan; Choi, Sang-Ho; Huh, Jin Won; Lim, Chae-Man; Koh, Younsuck; Hong, Sang-Bum

    2015-10-01

    The clinical efficacy of peramivir in the treatment of severe seasonal influenza in critically ill patients admitted to an intensive care unit (ICU) is not well established. The aim of this study was to compare the clinical efficacy of peramivir with that of oseltamivir in such critically ill patients. From September 2010 through March 2014, sixty patients with influenza confirmed by RT-PCR and hospitalized in our ICU were enrolled and reviewed retrospectively. Thirty-four and twenty-six patients received initial peramivir and oseltamivir, respectively. The median sequential organ failure assessment score was higher in the patients treated with peramivir (11 vs. 8.5, P= 0.029). There was no significant difference between the two groups in the median duration of use of antiviral agents. There were also no significant differences between the groups in 14-day (17.6% in peramivir vs. 7.7% in oseltamivir, P = 0.446), or 28-day mortality (35.3% in peramivir vs. 34.6% in oseltamivir, P = 0.813) or in the median length of ICU stay (11 days in peramivir vs. 12 days in oseltamivir, P=0.852). Peramivir has the similar clinical efficacy to oseltamivir in the treatment of severe seasonal influenza in the critically ill patients admitted to ICU. © 2015 Wiley Periodicals, Inc.

  10. Oseltamivir-Resistant Pandemic (H1N1) 2009 Virus Infections, United States, 2010–11

    PubMed Central

    Storms, Aaron D.; Gubareva, Larisa V.; Su, Su; Wheeling, John T.; Okomo-Adhiambo, Margaret; Pan, Chao-Yang; Reisdorf, Erik; St. George, Kirsten; Myers, Robert; Wotton, Jason T.; Robinson, Sara; Leader, Brandon; Thompson, Martha; Shannon, Marjorie; Klimov, Alexander

    2012-01-01

    During October 2010–July 2011, 1.0% of pandemic (H1N1) 2009 viruses in the United States were oseltamivir resistant, compared with 0.5% during the 2009–10 influenza season. Of resistant viruses from 2010–11 and 2009–10, 26% and 89%, respectively, were from persons exposed to oseltamivir before specimen collection. Findings suggest limited community transmission of oseltamivir-resistant virus. PMID:22305467

  11. The stimulatory effects of caffeine with oseltamivir (Tamiflu) on light-dark behavior and open-field behavior in mice.

    PubMed

    Uchiyama, Hidemori; Toda, Akihisa; Imoto, Masumi; Nishimura, Satoko; Kuroki, Hiroaki; Soeda, Shinji; Shimeno, Hiroshi; Watanabe, Shigenori; Eyanagi, Reiko

    2010-01-22

    Abnormal behaviors and death associated with the use of oseltamivir (Tamiflu) have emerged as a major issue in influenza patients taking the drug. Here, we investigated the mechanisms underlying the effects of oseltamivir on the behavior of mice using light-dark and open-field preference tests. Oseltamivir (75 and 150 mg/kg, intraperitoneally (i.p.)) alone affected neither time spent in the open area in the light-dark preference test nor ambulation in the open-field test at 2h post-injection. However, a non-selective adenosine A(1)/A(2) receptor antagonist, caffeine (10mg/kg, i.p.) in combination with oseltamivir (150 mg/kg, i.p.) increased time spent in the open area in the light-dark preference test. This enhancement was not inhibited by a benzodiazepine receptor antagonist, flumazenil (10-20mg/kg, subcutaneously (s.c.)). Enhancement of ambulation in the open-field test was also observed when caffeine (10mg/kg, i.p.) was combined with oseltamivir (150 mg/kg, i.p.). This enhancement was inhibited by a dopamine D(2) receptor antagonist, haloperidol (0.1mg/kg, s.c.). Furthermore, an adenosine A(2) receptor antagonist, SCH58261 (3mg/kg, i.p.) in combination with oseltamivir (150 mg/kg, i.p.) increased ambulation in the open-field test, while an adenosine A(1) receptor antagonist, DPCPX (1-3mg/kg, i.p.) did not. These findings suggest that the actions of oseltamivir may involve the dopamine and adenosine systems. Our findings suggest that due to the interaction between central blockade of adenosine A(2) receptors by caffeine, and oseltamivir-induced behavioral changes, patients being treated with oseltamivir should be closely monitored. (c) 2009 Elsevier Ireland Ltd. All rights reserved.

  12. Outcome of influenza infection managed with oseltamivir in lung transplant recipients.

    PubMed

    Ison, Michael G; Sharma, Amita; Shepard, Jo-Anne O; Wain, John C; Ginns, Leo C

    2008-03-01

    Influenza causes significant morbidity and mortality in lung transplant recipients and likely predisposes to obliterative bronchiolitis. Neuraminidase inhibitors shorten the duration of symptoms and virus shedding and the number of antibiotic-requiring complications in ambulatory immunocompetent patients, although the efficacy of these agents in lung transplant recipients has not been assessed previously. In this study, 9 lung transplant patients who were treated with oseltamivir for influenza infections were identified and analyzed retrospectively. Oseltamivir was well tolerated. Infection resolved in all patients and there were no deaths. Two patients developed pneumonia shortly after their influenza infection and both responded to antibiotic therapy. None of the patients had persistent abnormalities noted on chest imaging and most did not show significant changes on pulmonary function testing. Two patients with the lowest pulmonary function test (PFT) values pre-infection had persistent defects after infection. Oseltamivir is well tolerated in lung transplant recipients and may reduce the risk of complications, although further studies are warranted.

  13. Targeted antiviral prophylaxis with oseltamivir in a summer camp setting.

    PubMed

    Kimberlin, David W; Escude, Janell; Gantner, Janel; Ott, Jeanne; Dronet, Melissa; Stewart, Timothy A; Jester, Penelope; Redden, David T; Chapman, Whitney; Hammond, Rob

    2010-04-01

    To describe the effectiveness of containment of novel influenza A(H1N1) infection at a summer camp. Targeted use of oseltamivir phosphate by individuals in close contact with influenza-confirmed cases. Boys' camp in Alabama in July 2009. A total of 171 campers, 48 camp counselors, and 27 camp staff. Campers with confirmed influenza received oseltamivir and were immediately isolated and sent home. All boys and counselors in the infected child's adjoining cabins received prophylactic oseltamivir for 10 days, including 8 campers at higher risk for influenza infection (eg, those with asthma, seizure disorder, or diabetes). Alcohol-based hand sanitizer was provided at each of the daily activities, in the boys' cabins, and in the dining hall, and counselors were educated by the medical staff on the spread of influenza and its prevention through good hand hygiene. All cabins, bathrooms, and community sports equipment were sprayed or wiped down with disinfectant each day. Main Outcome Measure Virologic confirmation of influenza. Three of the 171 campers tested positive for influenza A during the course of the 2-week fourth session, for an attack rate of 1.8%. The probability of observing 3 or fewer infected campers if the attack rate was 12% is less than 1 in 10,000,000 (P < .0000001). An exact 95% confidence interval based on 3 events among 171 individuals estimates the attack rate to be between 0.3% and 5.0%. While 31% to 57% of campers, counselors, or staff experienced nausea with the treatment, this did not result in discontinuation of therapy. No campers tested positive for influenza A after returning home at the end of the camp session. In conjunction with comprehensive hand sanitization and surface decontamination, a targeted approach to antiviral prophylaxis contained the spread of influenza in a summer camp setting.

  14. Emergence of Oseltamivir-Resistant Pandemic (H1N1) 2009 Virus within 48 Hours

    PubMed Central

    Inoue, Masafumi; Leo, Yee-Sin; Chan, Kwai-Peng; Chow, Angela; Wong, Christopher W.; Lee, Raphael Tze-Chuen; Maurer-Stroh, Sebastian; Lin, Raymond; Lin, Cui

    2010-01-01

    An oseltamivir-resistant influenza A pandemic (H1N1) 2009 virus evolved and emerged from zero to 52% of detectable virus within 48 hours of a patient’s exposure to oseltamivir. Phylogenetic analysis and data gathered by pyrosequencing and cloning directly on clinical samples suggest that the mutant emerged de novo. PMID:20875299

  15. Stability of oseltamivir in various extemporaneous liquid preparations.

    PubMed

    Ford, Stephen M; Kloesel, Lawson G; Grabenstein, John D

    2007-01-01

    The purpose of this study was to determine the stability of oseltamivir, the active ingredient in Tamiflu, in contemporaneously compounded suspensions for a period of not less than 90 days. The suspension vehicles provided for the study were chosen because of ease of preparation, commercial availability, and palatability. Stability of the active ingredient was demonstrated for suspensions prepared in PCCA-Plus, PCCA Acacia, and 1% methylcellulose and was independent of storage temperature (tested temperatures were 2 deg C to 8 deg C and 25 deg C). A control sample of the commercial liquid form of Tamiflu was prepared, stored and analyzed along with the samples prepared from the contents of capsules. There was no difference in the apparent stability of the two forms of the drug preparation.

  16. Genetic makeup of amantadine-resistant and oseltamivir-resistant human influenza A/H1N1 viruses.

    PubMed

    Zaraket, Hassan; Saito, Reiko; Suzuki, Yasushi; Baranovich, Tatiana; Dapat, Clyde; Caperig-Dapat, Isolde; Suzuki, Hiroshi

    2010-04-01

    The emergence and widespread occurrence of antiviral drug-resistant seasonal human influenza A viruses, especially oseltamivir-resistant A/H1N1 virus, are major concerns. To understand the genetic background of antiviral drug-resistant A/H1N1 viruses, we performed full genome sequencing of prepandemic A/H1N1 strains. Seasonal influenza A/H1N1 viruses, including antiviral-susceptible viruses, amantadine-resistant viruses, and oseltamivir-resistant viruses, obtained from several areas in Japan during the 2007-2008 and 2008-2009 influenza seasons were analyzed. Sequencing of the full genomes of these viruses was performed, and the phylogenetic relationships among the sequences of each individual genome segment were inferred. Reference genome sequences from the Influenza Virus Resource database were included to determine the closest ancestor for each segment. Phylogenetic analysis revealed that the oseltamivir-resistant strain evolved from a reassortant oseltamivir-susceptible strain (clade 2B) which circulated in the 2007-2008 season by acquiring the H275Y resistance-conferring mutation in the NA gene. The oseltamivir-resistant lineage (corresponding to the Northern European resistant lineage) represented 100% of the H1N1 isolates from the 2008-2009 season and further acquired at least one mutation in each of the polymerase basic protein 2 (PB2), polymerase basic protein 1 (PB1), hemagglutinin (HA), and neuraminidase (NA) genes. Therefore, a reassortment event involving two distinct oseltamivir-susceptible lineages, followed by the H275Y substitution in the NA gene and other mutations elsewhere in the genome, contributed to the emergence of the oseltamivir-resistant lineage. In contrast, amantadine-resistant viruses from the 2007-2008 season distinctly clustered in clade 2C and were characterized by extensive amino acid substitutions across their genomes, suggesting that a fitness gap among its genetic components might have driven these mutations to maintain it in the

  17. Oseltamivir resistance among influenza viruses: surveillance in northern Viet Nam, 2009-2012.

    PubMed

    Hoang Vu, Mai-Phuong; Nguyen, Co Thach; Nguyen, Le Khanh Hang; Nguyen, Thi Kim Phuong; Le, Quynh Mai

    2013-01-01

    Antiviral resistance has been reported in seasonal influenza A viruses and avian influenza A(H5N1) viruses in Viet Nam, raising concerns about the efficacy of treatment. We analysed specimens from two sources during the period 2009-2012: influenza-positive samples from influenza-like illness patients at sentinel clinics in northern Viet Nam and isolates from patients with confirmed A(H5N1) infections. Pyrosequencing was used to detect mutations: H275Y [for A(H1N1) and A(H5N1)], E119V [for A(H3N2)] and I117V [for A(H5N1)]. A neuraminidase inhibition assay was used to determine the Inhibitory Concentration 50 (IC₅₀) values for all influenza A and B isolates. There were 341 influenza A positive samples identified; influenza A(H1N1)pdm09 was identified most frequently (n = 215). In 2009, oseltamivir resistance was observed in 100% (19 of 19) of seasonal A(H1N1) isolates and 1.4% (3/215) of A(H1N1)pdm09 isolates. This H275Y mutation was not found in influenza subtypes A(H5N1) or A(H3N2) isolates. In Viet Nam, seasonal and A(H5N1) influenza vaccines are not currently available; thus, effective treatment is required. The presence of oseltamivir-resistant viruses is therefore a concern. Active surveillance for oseltamivir resistance among influenza viruses circulating in Viet Nam should be continued.

  18. Review of potential drug interaction between Oseltamivir and Warfarin and why it is important for emergency medicine physicians.

    PubMed

    Shah, Siddharth P; Patel, Kinner M; Subedi, Rogin; Gambhir, Harvir Singh

    2017-08-01

    Oseltamivir is a very commonly prescribed anti-viral medication by the Emergency Medicine (EM) physicians for the prophylactic and therapeutic treatment of Influenza infection. While the drug interaction of Warfarin with various antibiotics is known, the drug interaction between Oseltamivir and Warfarin is not common. We present a case where an 83-year female patient, on Warfarin for Pulmonary Embolism, had worsening of coagulopathy after she was started on Oseltamivir. The INR was monitored daily in our patient and Warfarin was stopped when the INR became supra-therapeutic. Our patient did not have any minor or major bleeding complication. This is the first reported case of Oseltamivir related worsening coagulopathy in patient on Warfarin to the best of our knowledge. Keeping in mind the possible interaction between the two as it was evident in our case and few other published reports, we recommend monitoring the INR closely in patients using Warfarin after they are started on Oseltamivir therapy. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Oseltamivir Prophylaxis Reduces Inflammation and Facilitates Establishment of Cross-Strain Protective T Cell Memory to Influenza Viruses

    PubMed Central

    Hurt, Aeron C.; Oshansky, Christine M.; Oh, Ding Yuan; Reading, Patrick C.; Chua, Brendon Y.; Sun, Yilun; Tang, Li; Handel, Andreas; Jackson, David C.; Turner, Stephen J.; Thomas, Paul G.; Kedzierska, Katherine

    2015-01-01

    CD8+ T cells directed against conserved viral regions elicit broad immunity against distinct influenza viruses, promote rapid virus elimination and enhanced host recovery. The influenza neuraminidase inhibitor, oseltamivir, is prescribed for therapy and prophylaxis, although it remains unclear how the drug impacts disease severity and establishment of effector and memory CD8+ T cell immunity. We dissected the effects of oseltamivir on viral replication, inflammation, acute CD8+ T cell responses and the establishment of immunological CD8+ T cell memory. In mice, ferrets and humans, the effect of osteltamivir on viral titre was relatively modest. However, prophylactic oseltamivir treatment in mice markedly reduced morbidity, innate responses, inflammation and, ultimately, the magnitude of effector CD8+ T cell responses. Importantly, functional memory CD8+ T cells established during the drug-reduced effector phase were capable of mounting robust recall responses. Moreover, influenza-specific memory CD4+ T cells could be also recalled after the secondary challenge, while the antibody levels were unaffected. This provides evidence that long-term memory T cells can be generated during an oseltamivir-interrupted infection. The anti-inflammatory effect of oseltamivir was verified in H1N1-infected patients. Thus, in the case of an unpredicted influenza pandemic, while prophylactic oseltamivir treatment can reduce disease severity, the capacity to generate memory CD8+ T cells specific for the newly emerged virus is uncompromised. This could prove especially important for any new influenza pandemic which often occurs in separate waves. PMID:26086392

  20. Persistent oseltamivir-resistant pandemic influenza A/H1N1 infection in an adult with cystic fibrosis

    PubMed Central

    Flight, William George; Bright-Thomas, Rowland; Mutton, Kenneth; Webb, Kevin; Jones, Andrew

    2011-01-01

    The authors report the case of a 25-year-old patient with cystic fibrosis (CF) who developed pandemic influenza A/H1N1 during a visit to the USA in August 2010. The patient has severe CF lung disease and takes maintenance oral corticosteroids. The influenza virus was positive for the H275Y oseltamivir-resistance mutation despite the patient never having received oseltamivir. The patient has remained sputum-positive for over 4 months despite inhaled zanamivir therapy. This is the first reported case of transmission of oseltamivir-resistant H1N1 influenza to a patient with CF. The frequency of prolonged sputum carriage of pandemic influenza and transmission of oseltamivir-resistant strains are unknown on a population level. However, if our observations are replicated in other CF patients, they are potentially of considerable importance to clinical and infection-control practices in this patient group. PMID:22696672

  1. Oseltamivir-Resistant Influenza Virus A (H1N1), Europe, 2007–08 Season

    PubMed Central

    Lackenby, Angie; Hungnes, Olav; Lina, Bruno; van der Werf, Sylvie; Schweiger, Brunhilde; Opp, Matthias; Paget, John; van de Kassteele, Jan; Hay, Alan; Zambon, Maria

    2009-01-01

    In Europe, the 2007–08 winter season was dominated by influenza virus A (H1N1) circulation through week 7, followed by influenza B virus from week 8 onward. Oseltamivir-resistant influenza viruses A (H1N1) (ORVs) with H275Y mutation in the neuraminidase emerged independently of drug use. By country, the proportion of ORVs ranged from 0% to 68%, with the highest proportion in Norway. The average weighted prevalence of ORVs across Europe increased gradually over time, from near 0 in week 40 of 2007 to 56% in week 19 of 2008 (mean 20%). Neuraminidase genes of ORVs possessing the H275Y substitution formed a homogeneous subgroup closely related to, but distinguishable from, those of oseltamivir-sensitive influenza viruses A (H1N1). Minor variants of ORVs emerged independently, indicating multiclonal ORVs. Overall, the clinical effect of ORVs in Europe, measured by influenza-like illness or acute respiratory infection, was unremarkable and consistent with normal seasonal activity. PMID:19331731

  2. [Similarity of Clinically Significant Neuropsychiatric Adverse Reactions Listed in Package Inserts between the Anti-influenza Drugs Oseltamivir and Amantadine (Possibility Attributable to Common Pharmacological Effects)].

    PubMed

    Ono, Hideki; Okamura, Maya; Fukushima, Akihiro

    2018-06-20

      The anti-influenza virus drug oseltamivir has been reported to have several pharmacological actions including blocking of nicotinic acetylcholine receptor channels and activation of the dopaminergic system. These pharmacological actions highly overlap those of amantadine, another anti-influenza virus drug authorized in Japan, and ester-type local anesthetics. Moreover, oseltamivir and amantadine can clinically induce similar adverse neuropsychiatric reactions. In the present study, from the database of the Pharmaceuticals and Medical Devices Agency (PMDA), we surveyed 2,576 drugs for which neuropsychiatric side effects similar to those of oseltamivir, amantadine and local anesthetics (abnormal behavior, confusion, consciousness disturbance, convulsion, delirium, delusion, hallucination, myoclonus, tremor) are listed as "clinically significant adverse reactions", and found 327 that had at least one of these adverse reactions. Other neuraminidase inhibitors (laninamivir, peramivir and zanamivir) did not elicit such adverse reactions. By discussing the pharmacological effects of drugs that elicit these adverse reactions, we propose that the similarity of adverse neuropsychiatric reactions between oseltamivir and amantadine is possibly attributable to their common pharmacological effects.

  3. Electrophysiological effects of an anti-influenza drug oseltamivir on the guinea-pig atrium: comparison with those of pilsicainide.

    PubMed

    Takahara, Akira; Suzuki, Sanae; Hagiwara, Mihoko; Nozaki, Shuhei; Sugiyama, Atsushi

    2013-01-01

    We assessed the effects of oseltamivir on the conduction velocity and effective refractory period in the guinea-pig atrium in comparison with those of a class Ic antiarrhythmic drug pilsicainide. The recording and stimulating electrodes were attached on the epicardium close to the sinus nodal region and on the left atrial appendage. Oseltamivir (10-100 µM) as well as pilsicainide (1-10 µM) decreased the atrial conduction velocity in a frequency-dependent manner. Both drugs also increased the effective refractory period in both atria; but the frequency-dependent property of oseltamivir was lacking in the left atrium, and it was less obvious in the right atrium compared with that of pilsicainide. These results suggest that oseltamivir can directly modify the electrophysiological functions in the guinea-pig atrium possibly via combination of Na(+) and K(+) channel-blocking actions.

  4. A multi-spectroscopic and molecular docking approach to investigate the interaction of antiviral drug oseltamivir with ct-DNA.

    PubMed

    Moghadam, Neda Hosseinpour; Salehzadeh, Sadegh; Shahabadi, Nahid; Golbedaghi, Reza

    2017-07-03

    The possible interaction between the antiviral drug oseltamivir and calf thymus DNA at physiological pH was studied by spectrophotometry, competitive spectrofluorimetry, differential pulse voltammogram (DPV), circular dichroism spectroscopy (CD), viscosity measurements, salt effect, and computational studies. Intercalation of oseltamivir between the base pairs of DNA was shown by a sharp increase in specific viscosity of DNA and a decrease of the peak current and a positive shift in differential pulse voltammogram. Competitive fluorescence experiments were performed using neutral red (NR) as a probe for the intercalation binding mode. The studies showed that oseltamivir is able to release the NR.

  5. Development of Oseltamivir Phosphonate Congeners as Anti-Influenza Agents

    PubMed Central

    Cheng, Ting-Jen R.; Weinheimer, Steven; Tarbet, E. Bart; Jan, Jia-Tsrong; Cheng, Yih-Shyun E.; Shie, Jiun-Jie; Chen, Chun-Lin; Chen, Chih-An; Hsieh, Wei-Che; Huang, Pei-Wei; Lin, Wen-Hao; Wang, Shi-Yun; Fang, Jim-Min; Hu, Oliver Yoa-Pu; Wong, Chi-Huey

    2012-01-01

    Oseltamivir phosphonic acid (tamiphosphor, 3a), its monoethyl ester (3c), guanidino-tamiphosphor (4a) and its monoethyl ester (4c) are potent inhibitors of influenza neuraminidases. They inhibit the replication of influenza viruses, including the oseltamivir-resistant H275Y strain, at low nM to pM levels, and significantly protect mice from infection with lethal doses of influenza viruses when orally administered with 1 mg/kg or higher doses. These compounds are stable in simulated gastric fluid, liver microsomes and human blood, and are largely free from binding to plasma proteins. Pharmacokinetic properties of these inhibitors are thoroughly studied in dogs, rats and mice. The absolute oral bioavailability of these compounds was lower than 12%. No conversion of monoester 4c to phosphonic acid 4a was observed in rats after intravenous administration, but partial conversion of 4c was observed with oral administration. Advanced formulation may be investigated to develop these new anti-influenza agents for better therapeutic use. PMID:23009169

  6. Oseltamivir Population Pharmacokinetics in the Ferret: Model Application for Pharmacokinetic/Pharmacodynamic Study Design

    PubMed Central

    Reddy, Micaela B.; Yang, Kuo-Hsiung; Rao, Gauri; Rayner, Craig R.; Nie, Jing; Pamulapati, Chandrasena; Marathe, Bindumadhav M.; Forrest, Alan; Govorkova, Elena A.

    2015-01-01

    The ferret is a suitable small animal model for preclinical evaluation of efficacy of antiviral drugs against various influenza strains, including highly pathogenic H5N1 viruses. Rigorous pharmacokinetics/pharmacodynamics (PK/PD) assessment of ferret data has not been conducted, perhaps due to insufficient information on oseltamivir PK. Here, based on PK data from several studies on both uninfected and influenza-infected groups (i.e., with influenza A viruses of H5N1 and H3N2 subtypes and an influenza B virus) and several types of anesthesia we developed a population PK model for the active compound oseltamivir carboxylate (OC) in the ferret. The ferret OC population PK model incorporated delayed first-order input, two-compartment distribution, and first-order elimination to successfully describe OC PK. Influenza infection did not affect model parameters, but anesthesia did. The conclusion that OC PK was not influenced by influenza infection must be viewed with caution because the influenza infections in the studies included here resulted in mild clinical symptoms in terms of temperature, body weight, and activity scores. Monte Carlo simulations were used to determine that administration of a 5.08 mg/kg dose of oseltamivir phosphate to ferret every 12 h for 5 days results in the same median OC area under the plasma concentration-time curve 0–12 h (i.e., 3220 mg h/mL) as that observed in humans during steady state at the approved dose of 75 mg twice daily for 5 days. Modeling indicated that PK variability for OC in the ferret model is high, and can be affected by anesthesia. Therefore, for proper interpretation of PK/PD data, sparse PK sampling to allow the OC PK determination in individual animals is important. Another consideration in appropriate design of PK/PD studies is achieving an influenza infection with pronounced clinical symptoms and efficient virus replication, which will allow adequate evaluation of drug effects. PMID:26460484

  7. Design, in silico studies, synthesis and in vitro evaluation of oseltamivir derivatives as inhibitors of neuraminidase from influenza A virus H1N1.

    PubMed

    Neri-Bazán, Rocío M; García-Machorro, Jazmín; Méndez-Luna, David; Tolentino-López, Luis E; Martínez-Ramos, Federico; Padilla-Martínez, Itzia I; Aguilar-Faisal, Leopoldo; Soriano-Ursúa, Marvin A; Trujillo-Ferrara, José G; Fragoso-Vázquez, M Jonathan; Barrón, Blanca L; Correa-Basurto, José

    2017-03-10

    Since the neuraminidase (NA) enzyme of the influenza A virus plays a key role in the process of release of new viral particles from a host cell, it is often a target for new drug design. The emergence of NA mutations, such as H275Y, has led to great resistance against neuraminidase inhibitors, including oseltamivir and zanamivir. Hence, we herein designed a set of derivatives by modifying the amine and/or carboxylic groups of oseltamivir. After being screened for their physicochemical (Lipinski's rule) and toxicological properties, the remaining compounds were submitted to molecular and theoretical studies. The docking simulations provided insights into NA recognition patterns, demonstrating that oseltamivir modified at the carboxylic moiety and coupled with anilines had higher affinity and a better binding pose for NA than the derivatives modified at the amine group. Based on these theoretical studies, the new oseltamivir derivatives may have higher affinity to mutant variants and possibly to other viral subtypes. Accordingly, two compounds were selected for synthesis, which together with their respective intermediates were evaluated for their cytotoxicity and antiviral activities. Their biological activity was then tested in cells infected with the A/Puerto Rico/916/34 (H1N1) influenza virus, and virus yield reduction assays were performed. Additionally, by measuring neuraminidase activity with the neuraminidase assay kit it was found that the compounds produced inhibitory activity on this enzyme. Finally, the infected cells were analysed with atomic force microscopy (AFM), observing morphological changes strongly suggesting that these compounds interfered with cellular release of viral particles. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  8. Characteristics of a Widespread Community Cluster of H275Y Oseltamivir-Resistant A(H1N1)pdm09 Influenza in Australia

    PubMed Central

    Hurt, A. C.; Hardie, K.; Wilson, N. J.; Deng, Y. M.; Osbourn, M.; Leang, S. K.; Lee, R. T. C.; Iannello, P.; Gehrig, N.; Shaw, R.; Wark, P.; Caldwell, N.; Givney, R. C.; Xue, L.; Maurer-Stroh, S.; Dwyer, D. E.; Wang, B.; Smith, D. W.; Levy, A.; Booy, R.; Dixit, R.; Merritt, T.; Kelso, A.; Dalton, C.; Durrheim, D.; Barr, I. G.

    2012-01-01

    Background. Oseltamivir resistance in A(H1N1)pdm09 influenza is rare, particularly in untreated community cases. Sustained community transmission has not previously been reported. Methods. Influenza specimens from the Asia–Pacific region were collected through sentinel surveillance, hospital, and general practitioner networks. Clinical and epidemiological information was collected on patients infected with oseltamivir-resistant viruses. Results. Twenty-nine (15%) of 191 A(H1N1)pdm09 viruses collected between May and September 2011 from Hunter New England (HNE), Australia, contained the H275Y neuraminidase substitution responsible for oseltamivir resistance. Only 1 patient had received oseltamivir before specimen collection. The resistant strains were genetically very closely related, suggesting the spread of a single variant. Ninety percent of cases lived within 50 kilometers. Three genetically similar oseltamivir-resistant variants were detected outside of HNE, including 1 strain from Perth, approximately 4000 kilometers away. Computational analysis predicted that neuraminidase substitutions V241I, N369K, and N386S in these viruses may offset the destabilizing effect of the H275Y substitution. Conclusions This cluster represents the first widespread community transmission of H275Y oseltamivir-resistant A(H1N1)pdm09 influenza. These cases and data on potential permissive mutations suggest that currently circulating A(H1N1)pdm09 viruses retain viral fitness in the presence of the H275Y mutation and that widespread emergence of oseltamivir-resistant strains may now be more likely. PMID:22561367

  9. Evaluation of oseltamivir prophylaxis regimens for reducing influenza virus infection, transmission and disease severity in a ferret model of household contact

    PubMed Central

    Oh, Ding Yuan; Lowther, Sue; McCaw, James M.; Sullivan, Sheena G.; Leang, Sook-Kwan; Haining, Jessica; Arkinstall, Rachel; Kelso, Anne; Mcvernon, Jodie; Barr, Ian G.; Middleton, Deborah; Hurt, Aeron C.

    2014-01-01

    Objectives The emergence of the pandemic influenza A(H1N1)pdm09 virus in 2009 saw a significant increase in the therapeutic and prophylactic use of neuraminidase inhibitors (NAIs) to mitigate the impact of this highly transmissible virus. Prior to the pandemic, many countries stockpiled NAIs and developed pandemic plans for the use of antiviral drugs, based on either treatment of high-risk individuals and/or prophylaxis of contacts. However, to date there has been a lack of in vivo models to test the efficacy of treatment or prophylaxis with NAIs, for influenza-infected individuals or exposed contacts, in a household setting. Methods A ferret model of household contact was developed to study the efficacy of different prophylaxis regimens in preventing infection in contact ferrets exposed to influenza A(H1N1)pdm09-infected index ferrets. Results Among the different prophylactic regimens, contact ferrets receiving oseltamivir prophylaxis twice daily showed better outcomes than those receiving oseltamivir once daily. Benefits included a significant delay in the time to secondary infection, lower weight loss and higher activity levels. The treatment of index ferrets at 36 h post-infection did not influence either secondary infection rates or clinical symptoms in exposed contact ferrets. Neither prophylaxis nor treatment prevented infection or reduced the duration of viral shedding, although clinical symptoms did improve in infected animals receiving prophylaxis. Conclusions Different oseltamivir prophylaxis regimens did not prevent infections, but consistently resulted in a reduction in symptoms in infected ferrets. However, oseltamivir prophylaxis failed to reduce viral titres, which warrants further investigation in humans. PMID:24840623

  10. Evaluation of oseltamivir prophylaxis regimens for reducing influenza virus infection, transmission and disease severity in a ferret model of household contact.

    PubMed

    Oh, Ding Yuan; Lowther, Sue; McCaw, James M; Sullivan, Sheena G; Leang, Sook-Kwan; Haining, Jessica; Arkinstall, Rachel; Kelso, Anne; Mcvernon, Jodie; Barr, Ian G; Middleton, Deborah; Hurt, Aeron C

    2014-09-01

    The emergence of the pandemic influenza A(H1N1)pdm09 virus in 2009 saw a significant increase in the therapeutic and prophylactic use of neuraminidase inhibitors (NAIs) to mitigate the impact of this highly transmissible virus. Prior to the pandemic, many countries stockpiled NAIs and developed pandemic plans for the use of antiviral drugs, based on either treatment of high-risk individuals and/or prophylaxis of contacts. However, to date there has been a lack of in vivo models to test the efficacy of treatment or prophylaxis with NAIs, for influenza-infected individuals or exposed contacts, in a household setting. A ferret model of household contact was developed to study the efficacy of different prophylaxis regimens in preventing infection in contact ferrets exposed to influenza A(H1N1)pdm09-infected index ferrets. Among the different prophylactic regimens, contact ferrets receiving oseltamivir prophylaxis twice daily showed better outcomes than those receiving oseltamivir once daily. Benefits included a significant delay in the time to secondary infection, lower weight loss and higher activity levels. The treatment of index ferrets at 36 h post-infection did not influence either secondary infection rates or clinical symptoms in exposed contact ferrets. Neither prophylaxis nor treatment prevented infection or reduced the duration of viral shedding, although clinical symptoms did improve in infected animals receiving prophylaxis. Different oseltamivir prophylaxis regimens did not prevent infections, but consistently resulted in a reduction in symptoms in infected ferrets. However, oseltamivir prophylaxis failed to reduce viral titres, which warrants further investigation in humans. © The Author 2014. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy.

  11. Efficacy and Safety of Oseltamivir in Children: Systematic Review and Individual Patient Data Meta-analysis of Randomized Controlled Trials.

    PubMed

    Malosh, Ryan E; Martin, Emily T; Heikkinen, Terho; Brooks, W Abdullah; Whitley, Richard J; Monto, Arnold S

    2018-05-02

    Oseltamivir has been used to treat children with influenza for nearly 2 decades, with treatment currently approved for infants aged ≥2 weeks. However, efficacy and safety remain controversial. Newer randomized, placebo-controlled trials (RCTs), not included in previous meta-analyses, can add to the evidence base. We conducted a systematic review to identify RCTs of oseltamivir therapy in children. We obtained individual patient data and examined protocol-defined outcomes. We then conducted a 2-stage, random-effects meta-analysis to determine the efficacy of treatment in reducing the duration of illness, estimated using differences in restricted mean survival time (RMST) by treatment group. We also examined complications and safety. We identified 5 trials that included 2561 patients in the intention-to-treat (ITT) and 1598 in the intention-to-treat infected (ITTI) populations. Overall, oseltamivir treatment significantly reduced the duration of illness in the ITTI population (RMST difference, -17.6 hours; 95% confidence interval [CI], -34.7 to -0.62 hours). In trials that enrolled patients without asthma, the difference was larger (-29.9 hours; 95% CI, -53.9 to -5.8 hours). Risk of otitis media was 34% lower in the ITTI population. Vomiting was the only adverse event with a significantly higher risk in the treatment group. Despite substantial heterogeneity in pediatric trials, we found that treatment with oseltamivir significantly reduced the duration of illness in those with influenza and lowered the risk of developing otitis media. Alternative endpoints may be required to evaluate the efficacy of oseltamivir in pediatric patients with asthma.

  12. Oseltamivir prophylaxis in controlling influenza outbreak in nursing homes: a comparison between three different approaches.

    PubMed

    Gorišek Miksić, N; Uršič, T; Simonović, Z; Lusa, L; Lobnik Rojko, P; Petrovec, M; Strle, F

    2015-02-01

    To assess influenza outbreaks in nursing homes (NHs) using different pharmacological preventive measures. We compared characteristics of influenza A outbreaks that occurred during 2011/2012 influenza season in three NHs of similar size (208, 167, and 164 residents in NH1, NH2, and NH3, respectively) implementing comparable treatment approaches and non-pharmacological outbreak control measures but different prophylactic pharmacological interventions including oseltamivir 75 mg o.d. for 10 days for all residents (NH1), for directly exposed residents (NH2), and no prophylaxis (NH3). The proportions of residents who developed acute respiratory infection (ARI) in the course of influenza outbreak were 55/208 (26.4 %) in NH1, 64/167 (38.3 %) in NH2, and 31/164 (18.9 %) in NH3; hospital admission was required in 2/55 (3.6 %), 5/64 (7.8 %), and 5/31 (16.1 %) residents of NH1, NH2, and NH3, respectively, while 1/55 (1.8 %), 1/64 (1.6 %), and 3/31 (9.7 %) residents of the corresponding NHs died during influenza outbreak. The duration of the outbreak was shorter in the NH1 where oseltamivir prophylaxis was instituted for all residents (8 days), than in NHs where selective prophylaxis with oseltamivir and no prophylaxis were used (14 and 12 days, respectively). The calculated vaccine effectiveness in residents was 48, 71, and 44 % in NH1, NH2, and NH3, respectively. Staff members had similar ARI attack rate but in comparison to residents were less often vaccinated against influenza and demonstrated higher influenza vaccine effectiveness. Comparison of influenza outbreaks in three NHs revealed that the duration of the outbreak was the shortest in the NH where prophylaxis with oseltamivir was given to all residents.

  13. Development of A Concise Synthesis of (−)-Oseltamivir (Tamiflu®)

    PubMed Central

    Trost, Barry M.; Zhang, Ting

    2011-01-01

    We report a full account of our work towards the development of an eight-step synthesis of anti-influenza drug (−)-oseltamivir (Tamiflu®) from commercially available starting material. The final synthetic route proceeds with an overall yield of 30 %. Key transformations include a novel palladium-catalyzed asymmetric allylic alkylation reaction (Pd-AAA) as well as a rhodium-catalyzed chemo-, regio-, and stereoselective aziridination reaction. PMID:21365707

  14. Reducing Occurrence and Severity of Pneumonia Due to Pandemic H1N1 2009 by Early Oseltamivir Administration: A Retrospective Study in Mexico

    PubMed Central

    Higuera Iglesias, Anjarath Lorena; Kudo, Koichiro; Manabe, Toshie; Corcho Berdugo, Alexander Enrique; Baeza, Ariel Corrales; Ramos, Leticia Alfaro; Gutiérrez, René Guevara; Manjarrez Zavala, María Eugenia; Takasaki, Jin; Izumi, Shinyu; Bautista, Edgar; Perez Padilla, José Rogelio

    2011-01-01

    Background Anti-viral treatment has been used to treat severe or progressive illness due to pandemic H1N1 2009. A main cause of severe illness in pandemic H1N1 2009 is viral pneumonia; however, it is unclear how effective antiviral treatment is against pneumonia when administered >48 hours after symptom onset. Therefore, we aimed to determine how time from symptom onset to antiviral administration affected the effectiveness of antiviral treatment against pneumonia due to pandemic (H1N1) 2009. Methods/Principal Findings A retrospective medical chart review of 442 patients was conducted in a hospital in Mexico. Subjects had tested positive for pandemic H1N1 2009 virus by real-time reverse-transcriptase-polymerase-chain-reaction and were administered oseltamivir. Median time from symptom onset to oseltamivir administration was 5.0 days (range, 0–43). 442 subjects, 71 (16.1%) had severe pneumonia which required mechanical ventilation, 191 (43.2%) had mild to moderate pneumonia, and 180 (40%) did not have pneumonia. Subjects were divided into four groups based on time to oseltamivir administration: ≤2, 3–7, 8–14, and >14 days. Severity of respiratory features was associated with time to treatment, and multivariate analysis indicated that time to oseltamivir administration was associated with severity of respiratory features. A proportional odds model indicated that 50% probability for occurrence of pneumonia of any severity and that of severe pneumonia in patients who would develop pneumonia reached at approximately 3.4 and 21 days, respectively, after symptom onset. Patients with a shorter time to oseltamivir administration were discharged earlier from the hospital. Conclusions Earlier initiation of oseltamivir administration after symptom onset significantly reduced occurrence and severity of pneumonia and shortened hospitalization due to pandemic H1N1 2009. Even when administered >48 hours after symptom onset, oseltamivir showed considerable potential for

  15. Impact of early oseltamivir treatment on outcome in critically ill patients with 2009 pandemic influenza A.

    PubMed

    Rodríguez, Alejandro; Díaz, Emili; Martín-Loeches, Ignacio; Sandiumenge, Alberto; Canadell, Laura; Díaz, Juan J; Figueira, Juan C; Marques, Asunción; Alvarez-Lerma, Francisco; Vallés, Jordi; Baladín, Bárbara; García-López, Fernando; Suberviola, Borja; Zaragoza, Rafael; Trefler, Sandra; Bonastre, Juan; Blanquer, José; Rello, Jordi

    2011-05-01

    The impact of oseltamivir on mortality in critically ill patients with 2009 pandemic influenza A (2009 H1N1) is not clear. The main objective of this study was to investigate the relationship between the timing of antiviral administration and intensive care unit (ICU) outcomes. Prospective, observational study of a cohort of ICU patients with confirmed 2009 H1N1 infection. Clinical data, treatment and outcome were compared between patients receiving early treatment (ET) with oseltamivir, initiated within 2 days, and patients administered late treatment (LT), initiated after this timepoint. Multivariate analysis and propensity score were used to determine the effect of oseltamivir on ICU mortality. Six hundred and fifty-seven patients were enrolled. Four hundred and four (61.5%) patients required mechanical ventilation (MV; mortality 32.6%). Among them, 385 received effective antiviral therapy and were included in the study group. All patients received oseltamivir for a median duration of 10 days (interquartile range 8-14 days). Seventy-nine (20.5%) ET patients were compared with 306 LT patients. The two groups were comparable in terms of main clinical variables. ICU length of stay (22.7 ± 16.7 versus 18.4 ± 14.2 days; P = 0.03), hospital length of stay (34.0 ± 20.3 versus 27.2 ± 18.2 days; P = 0.001) and MV days (17.4 ± 15.2 versus 14.0 ± 12.4; P = 0.04) were higher in the LT group. ICU mortality was also higher in LT (34.3%) than in ET (21.5%; OR = 1.9; 95% CI 1.06-3.41). A multivariate model identified ET (OR = 0.44; 95% CI 0.21-0.87) as an independent variable associated with reduced ICU mortality. These results were confirmed by propensity score analysis (OR = 0.44; 95% CI 0.22-0.90; P < 0.001). Our findings suggest that early oseltamivir administration was associated with favourable outcomes among critically ill ventilated patients with 2009 H1N1 virus infection.

  16. Pharmaceutically active secondary metabolites of marine actinobacteria.

    PubMed

    Manivasagan, Panchanathan; Venkatesan, Jayachandran; Sivakumar, Kannan; Kim, Se-Kwon

    2014-04-01

    Marine actinobacteria are one of the most efficient groups of secondary metabolite producers and are very important from an industrial point of view. Many representatives of the order Actinomycetales are prolific producers of thousands of biologically active secondary metabolites. Actinobacteria from terrestrial sources have been studied and screened since the 1950s, for many important antibiotics, anticancer, antitumor and immunosuppressive agents. However, frequent rediscovery of the same compounds from the terrestrial actinobacteria has made them less attractive for screening programs in the recent years. At the same time, actinobacteria isolated from the marine environment have currently received considerable attention due to the structural diversity and unique biological activities of their secondary metabolites. They are efficient producers of new secondary metabolites that show a range of biological activities including antibacterial, antifungal, anticancer, antitumor, cytotoxic, cytostatic, anti-inflammatory, anti-parasitic, anti-malaria, antiviral, antioxidant, anti-angiogenesis, etc. In this review, an evaluation is made on the current status of research on marine actinobacteria yielding pharmaceutically active secondary metabolites. Bioactive compounds from marine actinobacteria possess distinct chemical structures that may form the basis for synthesis of new drugs that could be used to combat resistant pathogens. With the increasing advancement in science and technology, there would be a greater demand for new bioactive compounds synthesized by actinobacteria from various marine sources in future. Copyright © 2013 Elsevier GmbH. All rights reserved.

  17. Evaluation of the use of oseltamivir prophylaxis in the control of influenza outbreaks in long-term care facilities in Alberta, Canada: a retrospective provincial database analysis

    PubMed Central

    Ye, Ming; Jacobs, Angela; Khan, Muhammad Naeem; Jaipaul, Joy; Oda, Joanna; Johnson, Marcia; Doroshenko, Alexander

    2016-01-01

    Objectives To evaluate the impact of oseltamivir prophylaxis in the management and control of influenza outbreaks in long-term care facilities in Alberta, Canada. Setting and participants Long-term care facilities where 127 influenza outbreaks were reported to public health authorities in Alberta, Canada, during two influenza seasons from 2013 to 2015. Design and outcome measures Using routinely collected surveillance and administrative data, we examined the association between decision-making time for oseltamivir recommendation as prophylaxis strategy for influenza outbreaks in long-term care facilities (explanatory variable) and the duration of an influenza outbreak, the postprophylaxis risk of influenza-like illness and hospitalisation among residents of long-term care facilities in Alberta (outcome variables) using multivariable linear and Poisson regression models. Results Oseltamivir prophylaxis decision-making time was positively associated with the postintervention duration of an outbreak, with a 1-day delay in making decision on oseltamivir prophylaxis associated with 2.22 (95% CI 1.37 to 3.06) more days of the duration of an outbreak after controlling for potential confounding effect of the number of residents at risk at intervention, outbreak progression time, prevalence of influenza-like illness during outbreak progression, facility location, presence of mixed strain and based on optimal timing of oseltamivir prophylaxis. Although not statistically significant, a 1-day delay in making decision on oseltamivir prophylaxis was associated with a 5% (95% CI −1% to 11%) increase in the postintervention risk of influenza-like illness, and a 6% (95% CI −8% to 22%) increase in the postintervention risk of hospitalisation after controlling for the same potential confounders. Conclusions Our study demonstrated benefits of using oseltamivir prophylaxis to shorten the duration of influenza outbreaks; however, there were no significant differences in the

  18. Evaluation of the use of oseltamivir prophylaxis in the control of influenza outbreaks in long-term care facilities in Alberta, Canada: a retrospective provincial database analysis.

    PubMed

    Ye, Ming; Jacobs, Angela; Khan, Muhammad Naeem; Jaipaul, Joy; Oda, Joanna; Johnson, Marcia; Doroshenko, Alexander

    2016-07-05

    To evaluate the impact of oseltamivir prophylaxis in the management and control of influenza outbreaks in long-term care facilities in Alberta, Canada. Long-term care facilities where 127 influenza outbreaks were reported to public health authorities in Alberta, Canada, during two influenza seasons from 2013 to 2015. Using routinely collected surveillance and administrative data, we examined the association between decision-making time for oseltamivir recommendation as prophylaxis strategy for influenza outbreaks in long-term care facilities (explanatory variable) and the duration of an influenza outbreak, the postprophylaxis risk of influenza-like illness and hospitalisation among residents of long-term care facilities in Alberta (outcome variables) using multivariable linear and Poisson regression models. Oseltamivir prophylaxis decision-making time was positively associated with the postintervention duration of an outbreak, with a 1-day delay in making decision on oseltamivir prophylaxis associated with 2.22 (95% CI 1.37 to 3.06) more days of the duration of an outbreak after controlling for potential confounding effect of the number of residents at risk at intervention, outbreak progression time, prevalence of influenza-like illness during outbreak progression, facility location, presence of mixed strain and based on optimal timing of oseltamivir prophylaxis. Although not statistically significant, a 1-day delay in making decision on oseltamivir prophylaxis was associated with a 5% (95% CI -1% to 11%) increase in the postintervention risk of influenza-like illness, and a 6% (95% CI -8% to 22%) increase in the postintervention risk of hospitalisation after controlling for the same potential confounders. Our study demonstrated benefits of using oseltamivir prophylaxis to shorten the duration of influenza outbreaks; however, there were no significant differences in the influenza-like illness and hospitalisation risk occurring after the intervention. Surveillance

  19. Oseltamivir use and severe abnormal behavior in Japanese children and adolescents with influenza: Is a self-controlled case series study applicable?

    PubMed

    Fukushima, Wakaba; Ozasa, Kotaro; Okumura, Akihisa; Mori, Masaaki; Hosoya, Mitsuaki; Nakano, Takashi; Tanabe, Takuya; Yamaguchi, Naoto; Suzuki, Hiroshi; Mori, Mitsuru; Hatayama, Hideaki; Ochiai, Hirotaka; Kondo, Kyoko; Ito, Kazuya; Ohfuji, Satoko; Nakamura, Yosikazu; Hirota, Yoshio

    2017-08-24

    Since the 1990s, self-controlled designs including self-controlled case series (SCCS) studies have been occasionally used in post-marketing evaluation of drug or vaccine safety. An SCCS study was tentatively applied to evaluate the relationship between oseltamivir use and abnormal behavior Type A (serious abnormal behavior potentially leading to an accident or harm to another person) in influenza patients. From the original prospective cohort study with approximately 10,000 Japanese children and adolescents with influenza (aged <18years), 28 subjects (mean age: 7.3years) who developed abnormal behavior Type A after the first visit to the collaborating hospitals/clinics were analyzed. We hypothesized four combination patterns of the effect period (i.e., the period that effect of oseltamivir on occurrence of abnormal behavior Type A is likely) and the control period. Mantel-Haenszel rate ratio (M-H RR) and its 95% confidence interval (CI) were calculated as the relative risk estimate. Among 28 subjects in the SCCS study, 24 subjects (86%) were administered oseltamivir and 4 subjects (14%) were not. Abnormal behavior Type A was more likely to occur in the effect period than the control period in every pattern (M-H RR: 1.90-29.1). We observed the highest estimate when the effect period was set between the initial intake of oseltamivir and T max (M-H RR: 29.1, 95% CI: 4.21-201). Abnormal behavior Type A was more likely to develop up to approximately 30 times during the period between the initial intake of oseltamivir and T max . However, this period overlapped with the early period of influenza where high fever was observed. Since useful approaches to control the influence of the natural disease course of influenza were not available in this study, we could not deny the possibility that abnormal behavior was induced by influenza itself. The SCCS study was not an optimal method to evaluate the relationship between oseltamivir use and abnormal behavior. Copyright © 2017

  20. Interdisciplinary pharmacometrics linking oseltamivir pharmacology, influenza epidemiology and health economics to inform antiviral use in pandemics.

    PubMed

    Kamal, Mohamed A; Smith, Patrick F; Chaiyakunapruk, Nathorn; Wu, David B C; Pratoomsoot, Chayanin; Lee, Kenneth K C; Chong, Huey Yi; Nelson, Richard E; Nieforth, Keith; Dall, Georgina; Toovey, Stephen; Kong, David C M; Kamauu, Aaron; Kirkpatrick, Carl M; Rayner, Craig R

    2017-07-01

    A modular interdisciplinary platform was developed to investigate the economic impact of oseltamivir treatment by dosage regimen under simulated influenza pandemic scenarios. The pharmacology module consisted of a pharmacokinetic distribution of oseltamivir carboxylate daily area under the concentration-time curve at steady state (simulated for 75 mg and 150 mg twice daily regimens for 5 days) and a pharmacodynamic distribution of viral shedding duration obtained from phase II influenza inoculation data. The epidemiological module comprised a susceptible, exposed, infected, recovered (SEIR) model to which drug effect on the basic reproductive number (R 0 ), a measure of transmissibility, was linked by reduction of viral shedding duration. The number of infected patients per population of 100 000 susceptible individuals was simulated for a series of pandemic scenarios, varying oseltamivir dose, R 0 (1.9 vs. 2.7), and drug uptake (25%, 50%, and 80%). The number of infected patients for each scenario was entered into the health economics module, a decision analytic model populated with branch probabilities, disease utility, costs of hospitalized patients developing complications, and case-fatality rates. Change in quality-adjusted life years was determined relative to base case. Oseltamivir 75 mg relative to no treatment reduced the median number of infected patients, increased change in quality-adjusted life years by deaths averted, and was cost-saving under all scenarios; 150 mg relative to 75 mg was not cost effective in low transmissibility scenarios but was cost saving in high transmissibility scenarios. This methodological study demonstrates proof of concept that the disciplines of pharmacology, disease epidemiology and health economics can be linked in a single quantitative framework. © 2017 The British Pharmacological Society.

  1. Monitoring and Characterization of Oseltamivir-Resistant Pandemic (H1N1) 2009 Virus, Japan, 2009–2010

    PubMed Central

    Ujike, Makoto; Ejima, Miho; Anraku, Akane; Shimabukuro, Kozue; Obuchi, Masatsugu; Kishida, Noriko; Hong, Xu; Takashita, Emi; Fujisaki, Seiichiro; Yamashita, Kazuyo; Horikawa, Hiroshi; Kato, Yumiko; Oguchi, Akio; Fujita, Nobuyuki; Tashiro, Masato

    2011-01-01

    To monitor and characterize oseltamivir-resistant (OR) pandemic (H1N1) 2009 virus with the H275Y mutation, we analyzed 4,307 clinical specimens from Japan by neuraminidase (NA) sequencing or inhibition assay; 61 OR pandemic (H1N1) 2009 viruses were detected. NA inhibition assay and M2 sequencing indicated that OR pandemic (H1N1) 2009 virus was resistant to M2 inhibitors, but sensitive to zanamivir. Full-genome sequencing showed OR and oseltamivir-sensitive (OS) viruses had high sequence similarity, indicating that domestic OR virus was derived from OS pandemic (H1N1) 2009 virus. Hemagglutination inhibition test demonstrated that OR and OS pandemic (H1N1) 2009 viruses were antigenically similar to the A/California/7/2009 vaccine strain. Of 61 case-patients with OR viruses, 45 received oseltamivir as treatment, and 10 received it as prophylaxis, which suggests that most cases emerged sporadically from OS pandemic (H1N1) 2009, due to selective pressure. No evidence of sustained spread of OR pandemic (H1N1) 2009 was found in Japan; however, 2 suspected incidents of human-to-human transmission were reported. PMID:21392439

  2. Use of embryonated chicken egg as a model to study the susceptibility of avian influenza H9N2 viruses to oseltamivir carboxylate.

    PubMed

    Tare, Deeksha S; Pawar, Shailesh D

    2015-11-01

    Avian influenza (AI) H9N2 viruses are endemic in many bird species, and human infections of H9N2 viruses have been reported. Oseltamivir phosphate (Tamiflu(®)) is the available antiviral drug for the treatment and prophylaxis of influenza. There are no reports of use of embryonated chicken egg as a model to study susceptibility of AI viruses to oseltamivir carboxylate (OC), the active metabolite. The present study was undertaken to explore the use of embryonated chicken eggs as a model for testing OC against the AI H9N2 viruses. A total of three AI H9N2 viruses, isolated in poultry in India, were used. Various virus dilutions were tested against 14μg/ml of OC. Three methods, namely (1) the in vitro virus-drug treatment, (2) drug delivery and virus challenge by allantoic route, and (3) drug delivery by albumen route and virus challenge by allantoic route were explored. The viruses were also tested using the fluorescence-based neuraminidase inhibitor (NAI) assay. There was significant inhibition (p<0.05) of the H9N2 viruses in presence of OC. The infectious virus titers as well as hemagglutination titers were significantly lower in presence of OC as compared to controls. The in vitro treatment of virus and drug; and drug and virus delivery at the same time by allantoic route showed significantly higher inhibition (p<0.05) of virus growth than that by the albumen route. In the NAI assay, the half maximal inhibitory concentration (IC50) values of the H9N2 viruses were within the standard range for known susceptible reference virus. In conclusion, the H9N2 viruses used in the study were susceptible to OC. Embryonated chicken egg could be used as a model to study susceptibility of AI viruses to antiviral drugs. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Implementation of a rapid influenza A/B and RSV direct molecular assay improves emergency department oseltamivir use in paediatric patients.

    PubMed

    Mitchell, Stephanie L; Chang, Yeh-Chung; Feemster, Kristen; Cárdenas, Ana María

    2018-03-01

    Influenza A virus (FluA), influenza B virus (FluB) and respiratory syncytial virus (RSV) illnesses increase hospitalizations during seasonal epidemics. To determine the utility of the Simplexa FluA/B & RSV Direct Assay (Direct Flu/RSV) and its impact on oseltamivir use, we offered this assay to emergency department (ED) patients with influenza-like illness. Utilization of the Direct Flu/RSV provided a turnaround time (TAT) of 2 hours. Compared to the flu season prior to implementation of the Direct Flu/RSV, clinicians were more likely to prescribe 5 days of oseltamivir therapy for Direct Flu/RSV-positive patients in comparison to those with a negative test. Use of Direct Flu/RSV provides results rapidly, which leads to more appropriate use of oseltamivir. The ease of use of this assay and quick TAT allows for prompt decision-making, which is essential for patient care and effective disease control during the influenza season.

  4. Biologically Active Secondary Metabolites from the Fungi.

    PubMed

    Bills, Gerald F; Gloer, James B

    2016-11-01

    Many Fungi have a well-developed secondary metabolism. The diversity of fungal species and the diversification of biosynthetic gene clusters underscores a nearly limitless potential for metabolic variation and an untapped resource for drug discovery and synthetic biology. Much of the ecological success of the filamentous fungi in colonizing the planet is owed to their ability to deploy their secondary metabolites in concert with their penetrative and absorptive mode of life. Fungal secondary metabolites exhibit biological activities that have been developed into life-saving medicines and agrochemicals. Toxic metabolites, known as mycotoxins, contaminate human and livestock food and indoor environments. Secondary metabolites are determinants of fungal diseases of humans, animals, and plants. Secondary metabolites exhibit a staggering variation in chemical structures and biological activities, yet their biosynthetic pathways share a number of key characteristics. The genes encoding cooperative steps of a biosynthetic pathway tend to be located contiguously on the chromosome in coregulated gene clusters. Advances in genome sequencing, computational tools, and analytical chemistry are enabling the rapid connection of gene clusters with their metabolic products. At least three fungal drug precursors, penicillin K and V, mycophenolic acid, and pleuromutilin, have been produced by synthetic reconstruction and expression of respective gene clusters in heterologous hosts. This review summarizes general aspects of fungal secondary metabolism and recent developments in our understanding of how and why fungi make secondary metabolites, how these molecules are produced, and how their biosynthetic genes are distributed across the Fungi. The breadth of fungal secondary metabolite diversity is highlighted by recent information on the biosynthesis of important fungus-derived metabolites that have contributed to human health and agriculture and that have negatively impacted crops

  5. Preparation and stability of extemporaneous oral liquid formulations of oseltamivir using commercially available capsules.

    PubMed

    Winiarski, Aleksander P; Infeld, Martin H; Tscherne, Ronald; Bachynsky, Maria; Rucki, Richard; Nagano-Mate, Kathy

    2007-01-01

    To develop a simple, standardized method for the extemporaneous compounding of an oral liquid form of oseltamivir from commercially available Tamiflu 75 mg capsules (Roche Pharmaceuticals) and to determine the stability of oseltamivir in this preparation. Chemical and microbial stability study. Laboratory. None. Extemporaneous oral liquid formulations of oseltamivir (15 mg/mL) were prepared in Cherry Syrup (Humco) and Ora-Sweet SF (Paddock Laboratories) using methods consistent with current compounding practice in a pharmacy setting. Preparations were stored in amber glass and amber polyethyleneterephthalate bottles at 5 degrees C +/- 2 degrees C (41 degrees F +/- 4 degrees F) and 25 degrees C +/- 2 degrees C (77 degrees F +/- 4 degrees F) at 60% +/- 5% relative humidity (RH) for 35 days and 30 degrees C +/- 2 degrees C (86 degrees F +/- 4 degrees F) at 65% +/- 5% RH for 13 days. Samples were monitored for appearance, pH, assay, degradation products, and microbiologic stability. The Cherry Syrup preparation, in either bottle type, was stable for up to 35 days under refrigeration (5 degrees C) and up to 5 days at room temperature (25 degrees C). It was not stable when stored at 30 degrees C for 5 days. The Ora-Sweet SF preparation was stable for up to 35 days at 5 degrees C or 25 degrees C and for up to 13 days at 30 degrees C in either bottle type. Both preparations maintained microbiologic stability for 35 days. Both preparations are stable under the described conditions and may provide an option in situations where the marketed suspension is unavailable.

  6. Successful use of oseltamivir prophylaxis in managing a nosocomial outbreak of influenza A in a hematology and allogeneic stem cell transplant unit.

    PubMed

    Yue, Mimi C; Collins, Joel T; Subramoniapillai, Elango; Kennedy, Glen A

    2017-02-01

    To describe a nosocomial outbreak of H1N1 influenza A in an inpatient hematology and allogeneic stem cell transplant unit and outcomes of universal oseltamivir prophylaxis. Medical records of all patients admitted to the unit were reviewed to define the nosocomial outbreak, commencing 1 week prior to the index case until 4 weeks following institution of oseltamivir prophylaxis. Timelines for clinical symptoms, viral spread, management, patient outcomes and follow up testing were constructed. All cases of influenza were confirmed on nasopharyngeal swabs and/or bronchoalveolar lavages collected for polymerase chain reaction testing. In addition to the index case, further 11 patients were diagnosed with influenza A during the outbreak. Six patients (50%) had influenza-like-illness, five (42%) had respiratory symptoms only and one (8%) was asymptomatic. In total, five patients died, including four (33%) patients who were admitted to intensive care. A clustering of seven cases led to recognition of the outbreak and subsequent commencement of universal prophylaxis with oseltamivir 75 mg/day in all inpatients within the unit. Strict infection control processes were reinforced concurrently. There were no further cases of influenza A linked to the outbreak after the implementation of universal oseltamivir prophylaxis. Three later cases were linked to H1N1 exposure during the original outbreak. H1N1 influenza infection is associated with significant mortality in hematology patients. Universal prophylaxis with oseltamivir during a nosocomial outbreak appeared to be effective in controlling spread of the virus. We recommend early institution of infection control and universal prophylaxis in any nosocomial outbreak of influenza. © 2016 John Wiley & Sons Australia, Ltd.

  7. Secondary metabolites and insecticidal activity of Anemone pavonina.

    PubMed

    Varitimidis, Christos; Petrakis, Panos V; Vagias, Constantinos; Roussis, Vassilios

    2006-01-01

    The insecticidal properties of the crude extracts of the leaves and flowers of Anemone pavonina were evaluated on Pheidole pallidula ants and showed significant levels of activity. Bioassay-guided fractionations led to the isolation of the butenolide ranunculin (1) as the active principle. Chemical investigations of the extracts showed them to contain as major components the sitosterol glycopyranoside lipids 2-5 and the glycerides 6-8. The structures of the metabolites were elucidated, following acetylation and hydrolysis of the natural products, by interpretation of their NMR and mass spectral data. The uncommon lipid metabolites 2-8 were isolated for the first time from the genus Anemone and this is the first report of insecticidal activity of the Anemone metabolite ranunculin against ants.

  8. Factors associated with clinical and virological response in patients treated with oseltamivir or zanamivir for influenza A during the 2008-2009 winter.

    PubMed

    Blanchon, T; Mentré, F; Charlois-Ou, C; Dornic, Q; Mosnier, A; Bouscambert, M; Carrat, F; Duval, X; Enouf, V; Leport, C

    2013-02-01

    Oseltamivir or zanamivir are effective in outpatients with seasonal influenza; however, factors associated with response have been incompletely described. During the 2008/2009 epidemic, in a randomized trial for influenza A-infected outpatients, clinical (time to alleviation of flu-related symptoms) and virological (rate of patients with day 2 nasal viral load <200 cgeq/μL) responses to oseltamivir or zanamivir were assessed and associated factors were determined using multivariate analysis. For oseltamivir (141 patients) and zanamivir (149 patients) median times to alleviation of symptoms were 3 and 4 days, respectively; 59% and 34% had virological response. For oseltamivir, a lower clinical response was associated with female gender (HR, 0.53; 95% CI, 0.36-0.79), baseline symptoms score >14 (HR, 0.47; 0.32-0.70), viral load ≥5 log cgeq/μL (HR, 0.63; 0.43-0.93), and initiation of antibiotics (HR, 0.30; 0.12-0.76); a lower virological response was associated with female gender (OR, 0.45; 0.21-0.96), baseline viral load ≥5 log cgeq/μL (OR, 0.40; 0.20-0.84) and days 0-2 incomplete compliance (OR, 0.31; 0.10-0.98). For zanamivir, virological response was associated with age ≥50 years (OR, 0.29; 0.10-0.85) and initiation of antibiotics at baseline (OR, 4.24; 1.07-17.50). Factors associated with lower response to neuraminidase inhibitors in outpatients appeared to be easily identifiable during routine clinical examination and, when appropriate, by nasal sampling at baseline. The unknown association between gender and response to oseltamivir was not explained by compliance. © 2011 The Authors. Clinical Microbiology and Infection © 2011 European Society of Clinical Microbiology and Infectious Diseases.

  9. Role of R292K mutation in influenza H7N9 neuraminidase toward oseltamivir susceptibility: MD and MM/PB(GB)SA study

    NASA Astrophysics Data System (ADS)

    Phanich, Jiraphorn; Rungrotmongkol, Thanyada; Kungwan, Nawee; Hannongbua, Supot

    2016-10-01

    The H7N9 avian influenza virus is a novel re-assortment from at least four different strains of virus. Neuraminidase, which is a glycoprotein on the surface membrane, has been the target for drug treatment. However, some H7N9 strains that have been isolated from patient after drug treatment have a R292K mutation in neuraminidase. This substitution was found to facilitate drug resistance using protein- and virus- assays, in particular it gave a high resistance to the most commonly used drug, oseltamivir. The aim of this research is to understand the source of oseltamivir resistance using MD simulations and the MM/PB(GB)SA binding free energy approaches. Both methods can predict the reduced susceptibility of oseltamivir in good agreement to the IC 50 binding energy, although MM/GBSA underestimates this prediction compared to the MM/PBSA calculation. Electrostatic interaction is the main contribution for oseltamivir binding in terms of both interaction and solvation. We found that the source of the drug resistance is a decrease in the binding interaction combined with the reduction of the dehydration penalty. The smaller K292 mutated residue has a larger binding pocket cavity compared to the wild-type resulting in the loss of drug carboxylate-K292 hydrogen bonding and an increased accessibility for water molecules around the K292 mutated residue. In addition, oseltamivir does not bind well to the R292K mutant complex as shown by the high degree of fluctuation in ligand RMSD during the simulation and the change in angular distribution of bulky side chain groups.

  10. Oseltamivir-resistant influenza A(H1N1)pdm09 virus associated with high case fatality, India 2015.

    PubMed

    Tandel, Kundan; Sharma, Shashi; Dash, Paban Kumar; Parida, ManMohan

    2018-05-01

    Influenza A viruses has been associated with severe global pandemics of high morbidity and mortality with devastating impact on human health and global economy. India witnessed a major outbreak of influenza A(H1N1)pdm09 in 2015. This study comprises detailed investigation of cases died of influenza A(H1N1)pdm09 virus infection during explosive outbreak of 2015, in central part of India. To find out presence of drug resistant virus among patients who died of influenza A(H1N1)pdm09 virus infection and to find out presence of other mutations contributing to the morbidity and mortality. Twenty-two patients having confirmed influenza A(H1N1)pdm09 infection and subsequently died of this infection along with 20 non fatal cases with influenza A(H1N1)pdm09 infection were included in the study. Samples were investigated through RT-PCR/RFLP analysis, followed by nucleotide cycle sequencing of whole NA gene for detection of H275Y amino acid substitution in NA gene responsible for oseltamivir drug resistance. Out of 22 fatal cases, 6 (27.27%) were found to harbor oseltamivir resistant virus strains, whereas the H275Y mutation was not observed among the 20 non fatal cases. Amino acid substitution analysis of complete NA gene revealed V241I, N369K, N386K substitution in all strains playing synergistic role in oseltamivir drug resistance. High morbidity and mortality associated with influenza A(H1N1)pdm09 viruses can be explained by presence of drug resistant strains circulating in this outbreak. Presence of Oseltamivir resistant influenza A(H1N1)pdm09 viruses is a cause of great concern and warrants continuous screening for the circulation of drug resistant strains. © 2017 Wiley Periodicals, Inc.

  11. Physical activity, sedentary behavior, and vitamin D metabolites.

    PubMed

    Hibler, Elizabeth A; Sardo Molmenti, Christine L; Dai, Qi; Kohler, Lindsay N; Warren Anderson, Shaneda; Jurutka, Peter W; Jacobs, Elizabeth T

    2016-02-01

    Physical activity is associated with circulating 25-hydroxyvitamin D (25(OH)D). However, the influence of activity and/or sedentary behavior on the biologically active, seco-steroid hormone 1α,25-dihydroxyvitamin D (1,25(OH)2D) is unknown. We conducted a cross-sectional analysis among ursodeoxycholic acid (UDCA) randomized trial participants (n=876) to evaluate associations between physical activity, sedentary behavior, and circulating vitamin D metabolite concentrations. Continuous vitamin D metabolite measurements and clinical thresholds were evaluated using multiple linear and logistic regression models, mutually adjusted for either 1,25(OH)2D or 25(OH)D and additional confounding factors. A statistically significant linear association between 1,25(OH)2D and moderate-vigorous physical activity per week was strongest among women (β (95% CI): 3.10 (1.51-6.35)) versus men (β (95% CI): 1.35 (0.79-2.29)) in the highest tertile of activity compared to the lowest (p-interaction=0.003). Furthermore, 25(OH)D was 1.54ng/ml (95% CI 1.09-1.98) higher per hour increase in moderate-vigorous activity (p=0.001) and odds of sufficient 25(OH)D status was higher among physically active participants (p=0.001). Sedentary behavior was not significantly associated with either metabolite in linear regression models, nor was a statistically significant interaction by sex identified. The current study identified novel associations between physical activity and serum 1,25(OH)2D levels, adjusted for 25(OH)D concentrations. These results identify the biologically active form of vitamin D as a potential physiologic mechanism related to observed population-level associations between moderate-vigorous physical activity with bone health and chronic disease risk. However, future longitudinal studies are needed to further evaluate the role of physical activity and vitamin D metabolites in chronic disease prevention. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Efficacy of oseltamivir-zanamivir combination compared to each monotherapy for seasonal influenza: a randomized placebo-controlled trial.

    PubMed

    Duval, Xavier; van der Werf, Sylvie; Blanchon, Thierry; Mosnier, Anne; Bouscambert-Duchamp, Maude; Tibi, Annick; Enouf, Vincent; Charlois-Ou, Cécile; Vincent, Corine; Andreoletti, Laurent; Tubach, Florence; Lina, Bruno; Mentré, France; Leport, Catherine

    2010-11-02

    Neuraminidase inhibitors are thought to be efficacious in reducing the time to alleviation of symptoms in outpatients with seasonal influenza. The objective of this study was to compare the short-term virological efficacy of oseltamivir-zanamivir combination versus each monotherapy plus placebo. We conducted a randomized placebo-controlled trial with 145 general practitioners throughout France during the 2008-2009 seasonal influenza epidemic. Patients, general practitioners, and outcome assessors were all blinded to treatment assignment. Adult outpatients presenting influenza-like illness for less than 36 hours and a positive influenza A rapid test diagnosis were randomized to oseltamivir 75 mg orally twice daily plus zanamivir 10 mg by inhalation twice daily (OZ), oseltamivir plus inhaled placebo (O), or zanamivir plus oral placebo (Z). Treatment efficacy was assessed virologically according to the proportion of patients with nasal influenza reverse transcription (RT)-PCR below 200 copies genome equivalent (cgeq)/µl at day 2 (primary outcome), and clinically to the time to alleviation of symptoms until day 14. Overall 541 patients (of the 900 planned) were included (OZ,  =192; O, n=176; Z, n=173), 49% male, mean age 39 years. In the intention-to-treat analysis conducted in the 447 patients with RT-PCR-confirmed influenza A, 46%, 59%, and 34% in OZ (n=157), O (n=141), and Z (n=149) arms had RT-PCR<200 cgeq/µl (-13.0%, 95% confidence interval [CI] -23.1 to -2.9, p=0.025; +12.3%, 95% CI 2.39-22.2, p=0.028 for OZ/O and OZ/Z comparisons). Mean day 0 to day 2 viral load decrease was 2.14, 2.49, and 1.68 log(10) cgeq/µl (p=0.060, p=0.016 for OZ/O and OZ/Z). Median time to alleviation of symptoms was 4.0, 3.0, and 4.0 days (+1.0, 95% CI 0.0-4.0, p=0.018; +0.0, 95% CI -3.0 to 3.0, p=0.960 for OZ/O and OZ/Z). Four severe adverse events were observed. Nausea and/or vomiting tended to be more frequent in the combination arm (OZ, n=13; O, n=4; and Z, n=5 patients

  13. Clinical course of asthma patients with H1N1 influenza infection and oseltamivir.

    PubMed

    Kim, Min-Hye; Song, Woo-Jung; Yang, Min-Suk; Lee, So-Hee; Kwon, Jae-Woo; Kim, Sae-Hoon; Kang, Hye-Ryun; Park, Heung-Woo; Cho, Young-Joo; Cho, Sang-Heon; Min, Kyung-Up; Kim, You-Young; Chang, Yoon-Seok

    2018-02-01

    H1N1 influenza virus prevailed throughout the world in 2009. However, there are few reports on the clinical features of H1N1 influenza infection in adult asthma patients. We evaluated the clinical features in asthma patients with H1N1 influenza infection who took oseltamivir and compared them to those with other upper respiratory infections. We reviewed asthma patients over 15 years of age who had visited Seoul National University Hospital and Seoul National University Bundang Hospital for suspected H1N1 influenza infection from August 2009 to March 2010. Various clinical features such as hospital admission days, respiratory symptoms, basal lung function, and past history was compared between H1N1 influenza PCR positive and negative groups. A total of 111 asthmatics were enrolled. All patients took oseltamivir. H1N1 RT-PCR was positive in 62 patients (55.9%), negative in 49 patients (44.1%). Wheezing developed more frequently in the H1N1 positive group. (43.5 vs. 16.7%, P=0.044). The rate of acute asthma exacerbations and pneumonia development were higher in the H1N1 positive group (59.7 vs. 51%, P=0.015, 25.0% vs. 0%, P<0.001). The rates for emergency room visit, hospital admissions, intensive care unit admissions, hospital days were not different between the groups. Underlying medical conditions were accompanied more frequently in the H1N1 negative patients (21.6% vs. 30.6%, P=0.002), especially cardiac disease (7.2% vs. 15.3%, P=0.011). H1N1 influenza infection may affect the clinical course of asthma combined with more severe manifestations; however, Oseltamivir could have affected the clinical course of H1N1 infected patients and made it milder than expected.

  14. Biologically Active Metabolites Synthesized by Microalgae

    PubMed Central

    Costa, Jorge Alberto Vieira

    2015-01-01

    Microalgae are microorganisms that have different morphological, physiological, and genetic traits that confer the ability to produce different biologically active metabolites. Microalgal biotechnology has become a subject of study for various fields, due to the varied bioproducts that can be obtained from these microorganisms. When microalgal cultivation processes are better understood, microalgae can become an environmentally friendly and economically viable source of compounds of interest, because production can be optimized in a controlled culture. The bioactive compounds derived from microalgae have anti-inflammatory, antimicrobial, and antioxidant activities, among others. Furthermore, these microorganisms have the ability to promote health and reduce the risk of the development of degenerative diseases. In this context, the aim of this review is to discuss bioactive metabolites produced by microalgae for possible applications in the life sciences. PMID:26339647

  15. Effect of Oseltamivir Carboxylate Consumption on Emergence of Drug-Resistant H5N2 Avian Influenza Virus in Mallard Ducks

    PubMed Central

    Achenbach, Jenna E.

    2013-01-01

    Oseltamivir carboxylate (OC) has been detected in environmental waters at various levels during recent influenza seasons in humans, reflecting levels of usage and stability of this drug. In consideration of the role of waterfowl as hosts for influenza viruses that may contribute to human infections, we evaluated the effect of consumption of low doses of OC on development of oseltamivir-resistant influenza virus mutants in mallard ducks (Anas platyrhynchos) infected with two different low-pathogenic (LP) H5N2 avian influenza viruses (AIV). We detected development of virus variants carrying a known molecular marker of oseltamivir resistance (neuraminidase E119V) in 4 out of 6 mallards infected with A/Mallard/Minnesota/182742/1998 (H5N2) and exposed to 1,000 ng/liter OC. The mutation first appeared as a minor population on days 5 to 6 and was the dominant genotype on days 6 to 8. Oseltamivir-resistant mutations were not detected in virus from ducks not exposed to the drug or in ducks infected with a second strain of virus and similarly exposed to OC. Virus isolates carrying the E119V mutation displayed in vitro replication kinetics similar to those of the wild-type virus, but in vivo, the E119V virus rapidly reverted back to wild type in the absence of OC, and only the wild-type parental strain was transmitted to contact ducks. These results indicate that consumption by wild waterfowl of OC in drinking water may promote selection of the E119V resistance mutation in some strains of H5N2 AIV that could contribute to viruses infecting human populations. PMID:23459475

  16. Oseltamivir in influenza outbreaks in care homes: challenges and benefits of use in the real world.

    PubMed

    Millership, S; Cummins, A

    2015-08-01

    Respiratory virus infections, including influenza, are an important cause of potentially avoidable hospital admissions in the elderly. Although recent reviews have questioned the efficacy of oseltamivir in the prevention of transmission, it has been a central part of the authors' strategy to manage outbreaks in residential homes. To evaluate the management of respiratory virus infection outbreaks in residential homes, with particular emphasis on the logistics and effectiveness of antiviral prophylaxis with oseltamivir. A descriptive analysis was undertaken from a retrospective survey of records held on a local database for three northern hemisphere influenza seasons from 2010 to 2013. In total, 75 respiratory outbreaks were reported from 590 care homes during the study period; of these, the aetiological agent was confirmed as influenza in 35 outbreaks. Overall attack, hospital admission and death rates for influenza were 29.7%, 5.3% and 3.3%, respectively. A further 10 outbreaks were caused by parainfluenza, human metapneumovirus or respiratory syncytial virus in combination with each other or rhinovirus, and six outbreaks were caused by rhinovirus alone. No agent was identified for the remaining 24 outbreaks. Early public health involvement can lead to rapid termination of outbreaks of respiratory virus infections in residential homes. Although the use of oseltamivir is expensive, the data suggest that it does have some benefits as prophylaxis in this setting. Trials are needed to determine the most clinically and cost-effective interventions to control outbreaks in residential homes and avoid hospital admissions. Copyright © 2015 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  17. Secondary Metabolites from Three Florida Sponges with Antidepressant Activity

    PubMed Central

    Kochanowska, Anna J.; Rao, Karumanchi V.; Childress, Suzanne; El-Alfy, Abir; Matsumoto, Rae R.; Kelly, Michelle; Stewart, Gina S.; Sufka, Kenneth J.; Hamann, Mark T.

    2016-01-01

    Brominated indole alkaloids are a common class of metabolites reported from sponges of the order Verongida. Herein we report the isolation, structure determination, and activity of metabolites from three Florida sponges, namely, Verongula rigida (order Verongida, family Aplysinidae), Smenospongia aurea, and S. cerebriformis (order Dictyoceratida, family Thorectidae). All three species were investigated chemically, revealing similarities in secondary metabolites. Brominated compounds, as well as sesquiterpene quinones and hydroquinones, were identified from both V. rigida and S. aurea despite their apparent taxonomic differences at the ordinal level. Similar metabolites found in these distinct sponge species of two different genera provide evidence for a microbial origin of the metabolites. Isolated compounds were evaluated in the Porsolt forced swim test (FST) and the chick anxiety–depression continuum model. Among the isolated compounds, 5,6-dibromo-N,N-dimethyltryptamine (1) exhibited significant antidepressant-like action in the rodent FST model, while 5-bromo-N,N-dimethyltryptamine (2) caused significant reduction of locomotor activity indicative of a potential sedative action. The current study provides ample evidence that marine natural products with the diversity of brominated marine alkaloids will provide potential leads for antidepressant and anxiolytic drugs. PMID:18217716

  18. Secondary metabolites from three Florida sponges with antidepressant activity.

    PubMed

    Kochanowska, Anna J; Rao, Karumanchi V; Childress, Suzanne; El-Alfy, Abir; Matsumoto, Rae R; Kelly, Michelle; Stewart, Gina S; Sufka, Kenneth J; Hamann, Mark T

    2008-02-01

    Brominated indole alkaloids are a common class of metabolites reported from sponges of the order Verongida. Herein we report the isolation, structure determination, and activity of metabolites from three Florida sponges, namely, Verongula rigida (order Verongida, family Aplysinidae), Smenospongia aurea, and S. cerebriformis (order Dictyoceratida, family Thorectidae). All three species were investigated chemically, revealing similarities in secondary metabolites. Brominated compounds, as well as sesquiterpene quinones and hydroquinones, were identified from both V. rigida and S. aurea despite their apparent taxonomic differences at the ordinal level. Similar metabolites found in these distinct sponge species of two different genera provide evidence for a microbial origin of the metabolites. Isolated compounds were evaluated in the Porsolt forced swim test (FST) and the chick anxiety-depression continuum model. Among the isolated compounds, 5,6-dibromo- N,N-dimethyltryptamine ( 1) exhibited significant antidepressant-like action in the rodent FST model, while 5-bromo- N,N-dimethyltryptamine ( 2) caused significant reduction of locomotor activity indicative of a potential sedative action. The current study provides ample evidence that marine natural products with the diversity of brominated marine alkaloids will provide potential leads for antidepressant and anxiolytic drugs.

  19. Pathway Activity Profiling (PAPi): from the metabolite profile to the metabolic pathway activity.

    PubMed

    Aggio, Raphael B M; Ruggiero, Katya; Villas-Bôas, Silas Granato

    2010-12-01

    Metabolomics is one of the most recent omics-technologies and uses robust analytical techniques to screen low molecular mass metabolites in biological samples. It has evolved very quickly during the last decade. However, metabolomics datasets are considered highly complex when used to relate metabolite levels to metabolic pathway activity. Despite recent developments in bioinformatics, which have improved the quality of metabolomics data, there is still no straightforward method capable of correlating metabolite level to the activity of different metabolic pathways operating within the cells. Thus, this kind of analysis still depends on extremely laborious and time-consuming processes. Here, we present a new algorithm Pathway Activity Profiling (PAPi) with which we are able to compare metabolic pathway activities from metabolite profiles. The applicability and potential of PAPi was demonstrated using a previously published data from the yeast Saccharomyces cerevisiae. PAPi was able to support the biological interpretations of the previously published observations and, in addition, generated new hypotheses in a straightforward manner. However, PAPi is time consuming to perform manually. Thus, we also present here a new R-software package (PAPi) which implements the PAPi algorithm and facilitates its usage to quickly compare metabolic pathways activities between different experimental conditions. Using the identified metabolites and their respective abundances as input, the PAPi package calculates pathways' Activity Scores, which represents the potential metabolic pathways activities and allows their comparison between conditions. PAPi also performs principal components analysis and analysis of variance or t-test to investigate differences in activity level between experimental conditions. In addition, PAPi generates comparative graphs highlighting up- and down-regulated pathway activity. These datasets are available in http://www.4shared

  20. A cluster of patients infected with I221V influenza b virus variants with reduced oseltamivir susceptibility--North Carolina and South Carolina, 2010-2011.

    PubMed

    Garg, Shikha; Moore, Zack; Lee, Nicole; McKenna, John; Bishop, Amber; Fleischauer, Aaron; Springs, Chasisity B; Nguyen, Ha T; Sheu, Tiffany G; Sleeman, Katrina; Finelli, Lyn; Gubareva, Larisa; Fry, Alicia M

    2013-03-15

    During 2010-2011, influenza B viruses with a novel neuraminidase substitution, denoted I221V (B/I221V), associated with reduced in vitro oseltamivir susceptibility were detected in North Carolina. We determined the prevalence of I221V among B viruses submitted to the Centers for Disease Control and Prevention for antiviral resistance surveillance, including all B viruses submitted to North Carolina and South Carolina state laboratories, during October 2010-September 2011.We conducted chart reviews and telephone interviews to characterize North Carolina and South Carolina patients with B/I221V vs wild-type B virus infection (B/WT). We detected I221V in 45 (22%) of 209 B viruses from North Carolina and 8 (10%) of 82 B viruses from South Carolina. We detected I221V in 3 (0.3%) of 881 B viruses tested from 45 other states. B/I221V infection was not associated with differences in underlying conditions or illness severity, compared with B/WT infection. No patients with B/I221V infection received oseltamivir prior to specimen collection. Among patients who completed oseltamivir, those with B/I221V infection reported a longer duration until illness resolution (5 vs 3 days; P = .02). B/I221V cocirculated with B/WT in North Carolina and South Carolina during 2010-2011. I221V did not alter illness severity but may have reduced oseltamivir effectiveness. Thus, global surveillance for I221V is important.

  1. Intravenous zanamivir or oral oseltamivir for hospitalised patients with influenza: an international, randomised, double-blind, double-dummy, phase 3 trial.

    PubMed

    Marty, Francisco M; Vidal-Puigserver, Joan; Clark, Carol; Gupta, Sandeep K; Merino, Esperanza; Garot, Denis; Chapman, Marianne J; Jacobs, Frédérique; Rodriguez-Noriega, Eduardo; Husa, Petr; Shortino, Denise; Watson, Helen A; Yates, Phillip J; Peppercorn, Amanda F

    2017-02-01

    Neuraminidase inhibitors are effective for the treatment of acute uncomplicated influenza. However, there is an unmet need for intravenous treatment for patients admitted to hospital with severe influenza. We studied whether intravenous zanamivir was a suitable treatment in this setting. In this international, randomised, double-blind, double-dummy, phase 3 trial, we recruited patients aged 16 years or older with severe influenza admitted to 97 hospitals from 26 countries. We randomly assigned patients (1:1:1 stratified by symptom onset ≤4 days or 5-6 days) to receive 300 mg or 600 mg intravenous zanamivir, or standard-of-care (75 mg oral oseltamivir) twice a day for 5-10 days; patients were followed up for 28 days. The randomisation schedule, including stratification, was generated using GlaxoSmithKline's RandAll software. Patients, site study staff, and sponsor were masked to study treatment. The primary endpoint was time to clinical response-a composite of vital sign stabilisation and hospital discharge-in the influenza-positive population. The trial was powered to show an improvement of 1·5 days or greater with 600 mg intravenous zanamivir. Pharmacokinetic, safety, and virology endpoints were also assessed. This trial is registered with ClinicalTrials.gov, number NCT01231620. Between Jan 15, 2011, and Feb 12, 2015, 626 patients were randomly assigned to receive 300 mg intravenous zanamivir (n=201), 600 mg intravenous zanamivir (n=209), or 75 mg oral oseltamivir (n=205) twice a day; 11 patients discontinued the study before receiving any study treatment. 488 (78%) of 626 patients had laboratory-confirmed influenza. Compared with a median time to clinical response of 5·14 days in the 600 mg intravenous zanamivir group, the median time to clinical response was 5·87 days (difference of -0·73 days, 95% CI -1·79 to 0·75; p=0·25) in the 300 mg intravenous zanamivir group and 5·63 days (difference of -0·48 days, 95% CI -2·11 to 0·97; p=0·39) in the

  2. Use of oseltamivir after influenza infection is associated with reduced incidence of recurrent adverse cardiovascular outcomes among military health system beneficiaries with prior cardiovascular diseases.

    PubMed

    Casscells, S Ward; Granger, Elder; Kress, Amii M; Linton, Andrea; Madjid, Mohammad; Cottrell, Linda

    2009-03-01

    Influenza infection has been associated with increased risk of adverse cardiac and cerebral vascular outcomes. Oseltamivir, a treatment for influenza, has been shown to decrease the severity of an influenza episode, but few data exist regarding its potentially protective effect against recurrent vascular outcomes among influenza patients with a history of vascular disease. Electronic healthcare service and pharmacy records for 37,482 TRICARE beneficiaries, aged 18 and older, with a coded history of cardiovascular (CV) disease and a subsequent diagnosis of influenza from October 1, 2003, through September 30, 2007, were examined. Subjects were grouped according to whether they had filled a prescription for oseltamivir within 2 days of their influenza diagnosis. The incidence of recurrent CV events within 30 days after the influenza diagnosis among oseltavmivir-treated and untreated subjects was 8.5% and 21.2%, respectively (P<0.005). Subject age was a persistent and significant contributor to the likelihood of recurrent CV outcomes. After controlling for the differences in demographics among treated and untreated cohorts using a propensity-scored logistic regression model, a statistically significant protective effect was associated with oseltamivir treatment (odds ratio, 0.417; 95% CI, 0.349 to 0.498). Our findings suggests that oseltamivir treatment for influenza is associated with significant decrease in the risk of recurrent CV events in subjects with a history of CV disease. These findings merit confirmation in further prospective and controlled studies. Meanwhile, in patients with CV disease, strict adherence with current practice guidelines for prevention and treatment of influenza is recommended.

  3. Polymyxin-B-immobilized-fiber column hemoperfusion with oseltamivir treatment for ARDS due to influenza H1N1/09.

    PubMed

    Binh, Nguyen Gia; Manabe, Toshie; Co, Dao Xuan; Tuan, Nguyen Dang; Thach, Pham The; Kudo, Koichiro

    2015-06-01

    Acute respiratory distress syndrome (ARDS) is one of the severe complications of influenza H1N1/09 infection, resulting in high mortality. Effective treatment strategies for ARDS are needed. This report presents two cases of ARDS due to influenza in Vietnam. Both cases were similar in terms of starting symptoms, the rapid progression to ARDS, and the treatment strategy, direct hemoperfusion with a polymyxin-B-immobilized fiber column (PMX-DHP) and oseltamivir. However, the clinical course of disease and the outcomes were different. For case 1, treatment was initiated on day 4 following the onset of hypoxemia due to ARDS. Symptoms improved rapidly after treatment and the patient was discharged on day 12. For case 2, treatment was initiated on day 9 after the onset of symptoms. Despite intensive therapy, the patient died on day 18. In conclusion, treatment with PMX-DHP and oseltamivir is effective on ARDS due to influenza but only if initiated early.

  4. Estrogenic activities of diuron metabolites in female Nile tilapia (Oreochromis niloticus).

    PubMed

    Pereira, Thiago Scremin Boscolo; Boscolo, Camila Nomura Pereira; Felício, Andreia Arantes; Batlouni, Sergio Ricardo; Schlenk, Daniel; de Almeida, Eduardo Alves

    2016-03-01

    Some endocrine disrupting chemicals (EDCs) can alter the estrogenic activities of the organism by directly interacting with estrogen receptors (ER) or indirectly through the hypothalamus-pituitary-gonadal axis. Recent studies in male Nile tilapia (Oreochromis niloticus) indicated that diuron may have anti-androgenic activity augmented by biotransformation. In this study, the effects of diuron and three of its metabolites were evaluated in female tilapia. Sexually mature female fish were exposed for 25 days to diuron, as well as to its metabolites 3,4-dichloroaniline (DCA), 3,4-dichlorophenylurea (DCPU) and 3,4-dichlorophenyl-N-methylurea (DCPMU), at concentrations of 100 ng/L. Diuron metabolites caused increases in E2 plasma levels, gonadosomatic indices and in the percentage of final vitellogenic oocytes. Moreover, diuron and its metabolites caused a decrease in germinative cells. Significant differences in plasma concentrations of the estrogen precursor and gonadal regulator17α-hydroxyprogesterone (17α-OHP) were not observed. These results show that diuron metabolites had estrogenic effects potentially mediated through enhanced estradiol biosynthesis and accelerated the ovarian development of O. niloticus females. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Phytol metabolites are circulating dietary factors that activate the nuclear receptor RXR.

    PubMed Central

    Kitareewan, S; Burka, L T; Tomer, K B; Parker, C E; Deterding, L J; Stevens, R D; Forman, B M; Mais, D E; Heyman, R A; McMorris, T; Weinberger, C

    1996-01-01

    RXR is a nuclear receptor that plays a central role in cell signaling by pairing with a host of other receptors. Previously, 9-cis-retinoic acid (9cRA) was defined as a potent RXR activator. Here we describe a unique RXR effector identified from organic extracts of bovine serum by following RXR-dependent transcriptional activity. Structural analyses of material in active fractions pointed to the saturated diterpenoid phytanic acid, which induced RXR-dependent transcription at concentrations between 4 and 64 microM. Although 200 times more potent than phytanic acid, 9cRA was undetectable in equivalent amounts of extract and cannot be present at a concentration that could account for the activity. Phytanic acid, another phytol metabolite, was synthesized and stimulated RXR with a potency and efficacy similar to phytanic acid. These metabolites specifically displaced [3H]-9cRA from RXR with Ki values of 4 microM, indicating that their transcriptional effects are mediated by direct receptor interactions. Phytol metabolites are compelling candidates for physiological effectors, because their RXR binding affinities and activation potencies match their micromolar circulating concentrations. Given their exclusive dietary origin, these chlorophyll metabolites may represent essential nutrients that coordinate cellular metabolism through RXR-dependent signaling pathways. PMID:8856661

  6. Widespread occurrence of neuro-active pharmaceuticals and metabolites in 24 Minnesota rivers and wastewaters

    USGS Publications Warehouse

    Writer, Jeffrey; Ferrer, Imma; Barber, Larry B.; Thurman, E. Michael

    2013-01-01

    Concentrations of 17 neuro-active pharmaceuticals and their major metabolites (bupropion, hydroxy-bupropion, erythro-hydrobupropion, threo-hydrobupropion, carbamazepine, 10,11,-dihydro-10,11,-dihydroxycarbamazepine, 10-hydroxy-carbamazepine, citalopram, N-desmethyl-citalopram, fluoxetine, norfluoxetine, gabapentin, lamotrigine, 2-N-glucuronide-lamotrigine, oxcarbazepine, venlafaxine and O-desmethyl-venlafaxine), were measured in treated wastewater and receiving surface waters from 24 locations across Minnesota, USA. The analysis of upstream and downstream sampling sites indicated that the wastewater treatment plants were the major source of the neuro-active pharmaceuticals and associated metabolites in surface waters of Minnesota. Concentrations of parent compound and the associated metabolite varied substantially between treatment plants (concentrations ± standard deviation of the parent compound relative to its major metabolite) as illustrated by the following examples; bupropion and hydrobupropion 700 ± 1000 ng L−1, 2100 ± 1700 ng L−1, carbamazepine and 10-hydroxy-carbamazepine 480 ± 380 ng L−1, 360 ± 400 ng L−1, venlafaxine and O-desmethyl-venlafaxine 1400 ± 1300 ng L−1, 1800 ± 2300 ng L−1. Metabolites of the neuro-active compounds were commonly found at higher or comparable concentrations to the parent compounds in wastewater effluent and the receiving surface water. Neuro-active pharmaceuticals and associated metabolites were detected only sporadically in samples upstream from the effluent outfall. Metabolite to parent ratios were used to evaluate transformation, and we determined that ratios in wastewater were much lower than those reported in urine, indicating that the metabolites are relatively more labile than the parent compounds in the treatment plants and in receiving waters. The widespread occurrence of neuro-active pharmaceuticals and metabolites in Minnesota effluents and surface waters indicate that

  7. Resveratrol glucuronides as the metabolites of resveratrol in humans: characterization, synthesis, and anti-HIV activity.

    PubMed

    Wang, Lai-Xi; Heredia, Alonso; Song, Haijing; Zhang, Zhaojun; Yu, Biao; Davis, Charles; Redfield, Robert

    2004-10-01

    Resveratrol is a natural product with diverse biological activities. We have previously reported that resveratrol possesses potent synergistic inhibitory activity against human immunodeficiency virus (HIV)-1 infection in combination with nucleoside analogs (Heredia et al. 2000. J Acquir Immune Defic Syndr 25:246-255). As a part of our program in developing resveratrol as a component for anti-HIV chemotherapy, we describe in this article the characterization, chemical synthesis, and biological effects of the human metabolites of resveratrol. We found that resveratrol was metabolized in humans into two metabolites, which were characterized as resveratrol-3-O- and 4'-O-glucuronides. For further biological studies, we reported two simple, alternative methods for the synthesis of the metabolites. The cytotoxic and antiviral activities of resveratrol and its metabolites were compared in cell culture experiments using human peripheral blood mononuclear cells. Whereas resveratrol was cytotoxic at > or =30 microM, no cytotoxicity was observed for the metabolites at concentrations as high as 300 microM. However, resveratrol showed strong synergistic anti-HIV activity with didanosine at 10 microM, but no synergistic effects were observed for either of the metabolites at up to 300 microM. Nevertheless, the in vitro activity of the metabolites (resveratrol glucuronides) may not necessarily reflect their in vivo function, given the fact that the ubiquitously existing human beta-glucuronidase could convert the metabolites back to resveratrol locally or systematically in vivo. The present studies have implications for future development of resveratrol and/or its derivatives as a chemotherapeutic agent. Copyright 2004 Wiley-Liss, Inc. and the American Pharmacists Association

  8. [Influence of corynebacteria metabolites on antagonistic activity of H2O2 producing lactobacilli].

    PubMed

    Bukharin, O V; Sgibnev, A V

    2012-01-01

    Study combined influence of Corynebacterium genus bacteria metabolites and H2O2 producing lactobacilli on survival rate of Staphylococcus aureus, Escherichia coli and Lactobacillus acidophilus. The ability to inhibit catalase of the test strains used and to reduce bactericidal effect of hydroxyl radical were determined in corynebacteria. H2O2 containing metabolites were obtained by cultivating lactobacilli in mineral medium, the amount of H2O2 was determined by oxidation of TMB by peroxidase. Bactericidal effect of lactobacilli metabolites for test strains treated by corynebacteria metabolites was evaluated by seeding results. Results. Inhibitio by corynebacteria metabolites of S. aureus catalase activity by 30-40% and E. coli catalase activ ity by 40-70% was shown. A reduction of bactericidal effect of hydroxyl radicals by corynebacteria metabolites by 30-35% for S. aureus, 38-42% for E. coli and 70-73% for L. acidophilus was noted. The enchantment of bactericidal effect of lactobacilli after treatment of the test strain by corynebacteria metabolites against S. aureus and E. coli manifested by reduction of the numbe of viable cells by 2-3 lg CFU. For L. acidophilus the bactericidal effect oflactobacilli metabolite in the same conditions reduced, and that led to the increase ofviability by 2-4 lg PFU. A conclusion on the possibility of regulation by associative bacteria the manifestations of antagonistic activity of H2O2 producing dominant microorganisms is made based on the data obtained.

  9. Secondary metabolites profiles and antioxidant activities of germinated brown and red rice

    NASA Astrophysics Data System (ADS)

    Nurnaistia, Y.; Aisyah, S.; Munawaroh, H. S. H.; Zackiyah

    2018-05-01

    The research aims to investigate the effect of germination on the secondary metabolite profiles and antioxidant activity of brown and red rice. The germination was performed by using a simple laboratory-scale machine that was designed and optimized to provide conditions that support the germination process. The germination was carried out for 2 days in dark conditions at 26°C and 99% humidity. Analysis of the secondary metabolite profile of ungerminated and germinated rice was performed using LC-MS. The antioxidant activities of ungerminated and germinated rice were done by using DPPH method. The results showed that the profiles of secondary metabolites of brown and red rice changed after germination. Some peaks were found to be induced in the germinated rice. However, some peaks were also loss during germination. The antioxidant activity of brown rice was slightly increased due to the germination, from 11.2% to 22.5%. Meanwhile the antioxidant activity of red rice was decreased after germination, from 73.8% to 60.0%.

  10. Influenza B viruses with mutation in the neuraminidase active site, North Carolina, USA, 2010-11.

    PubMed

    Sleeman, Katrina; Sheu, Tiffany G; Moore, Zack; Kilpatrick, Susan; Garg, Shikha; Fry, Alicia M; Gubareva, Larisa V

    2011-11-01

    Oseltamivir is 1 of 2 antiviral medications available for the treatment of influenza B virus infections. We describe and characterize a cluster of influenza B viruses circulating in North Carolina with a mutation in the neuraminidase active site that may reduce susceptibility to oseltamivir and the investigational drug peramivir but not to zanamivir.

  11. Antifungal activity of microbial secondary metabolites.

    PubMed

    Coleman, Jeffrey J; Ghosh, Suman; Okoli, Ikechukwu; Mylonakis, Eleftherios

    2011-01-01

    Secondary metabolites are well known for their ability to impede other microorganisms. Reanalysis of a screen of natural products using the Caenorhabditis elegans-Candida albicans infection model identified twelve microbial secondary metabolites capable of conferring an increase in survival to infected nematodes. In this screen, the two compound treatments conferring the highest survival rates were members of the epipolythiodioxopiperazine (ETP) family of fungal secondary metabolites, acetylgliotoxin and a derivative of hyalodendrin. The abundance of fungal secondary metabolites indentified in this screen prompted further studies investigating the interaction between opportunistic pathogenic fungi and Aspergillus fumigatus, because of the ability of the fungus to produce a plethora of secondary metabolites, including the well studied ETP gliotoxin. We found that cell-free supernatant of A. fumigatus was able to inhibit the growth of Candida albicans through the production of a secreted product. Comparative studies between a wild-type and an A. fumigatus ΔgliP strain unable to synthesize gliotoxin demonstrate that this secondary metabolite is the major factor responsible for the inhibition. Although toxic to organisms, gliotoxin conferred an increase in survival to C. albicans-infected C. elegans in a dose dependent manner. As A. fumigatus produces gliotoxin in vivo, we propose that in addition to being a virulence factor, gliotoxin may also provide an advantage to A. fumigatus when infecting a host that harbors other opportunistic fungi.

  12. Antifungal Activity of Microbial Secondary Metabolites

    PubMed Central

    Okoli, Ikechukwu; Mylonakis, Eleftherios

    2011-01-01

    Secondary metabolites are well known for their ability to impede other microorganisms. Reanalysis of a screen of natural products using the Caenorhabditis elegans-Candida albicans infection model identified twelve microbial secondary metabolites capable of conferring an increase in survival to infected nematodes. In this screen, the two compound treatments conferring the highest survival rates were members of the epipolythiodioxopiperazine (ETP) family of fungal secondary metabolites, acetylgliotoxin and a derivative of hyalodendrin. The abundance of fungal secondary metabolites indentified in this screen prompted further studies investigating the interaction between opportunistic pathogenic fungi and Aspergillus fumigatus, because of the ability of the fungus to produce a plethora of secondary metabolites, including the well studied ETP gliotoxin. We found that cell-free supernatant of A. fumigatus was able to inhibit the growth of Candida albicans through the production of a secreted product. Comparative studies between a wild-type and an A. fumigatus ΔgliP strain unable to synthesize gliotoxin demonstrate that this secondary metabolite is the major factor responsible for the inhibition. Although toxic to organisms, gliotoxin conferred an increase in survival to C. albicans-infected C. elegans in a dose dependent manner. As A. fumigatus produces gliotoxin in vivo, we propose that in addition to being a virulence factor, gliotoxin may also provide an advantage to A. fumigatus when infecting a host that harbors other opportunistic fungi. PMID:21966496

  13. The effects of plant nutritional strategy on soil microbial denitrification activity through rhizosphere primary metabolites.

    PubMed

    Guyonnet, Julien P; Vautrin, Florian; Meiffren, Guillaume; Labois, Clément; Cantarel, Amélie A M; Michalet, Serge; Comte, Gilles; Haichar, Feth El Zahar

    2017-04-01

    The aim of this study was to determine (i) whether plant nutritional strategy affects the composition of primary metabolites exuded into the rhizosphere and (ii) the impact of exuded metabolites on denitrification activity in soil. We answered this question by analysing primary metabolite content extracted from the root-adhering soil (RAS) and the roots of three grasses representing different nutrient management strategies: conservative (Festuca paniculata), intermediate (Bromus erectus) and exploitative (Dactylis glomerata). We also investigated the impact of primary metabolites on soil microbial denitrification enzyme activity without carbon addition, comparing for each plant RAS and bulk soils. Our data show that plant nutritional strategy impacts on primary metabolite composition of root extracts or RAS. Further we show, for the first time, that RAS-extracted primary metabolites are probably better indicators to explain plant nutrient strategy than root-extracted ones. In addition, our results show that some primary metabolites present in the RAS were well correlated with soil microbial denitrification activity with positive relationships found between denitrification and the presence of some organic acids and negative ones with the presence of xylose. We demonstrated that the analysis of primary metabolites extracted from the RAS is probably more pertinent to evaluate the impact of plant on soil microbial community functioning. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  14. A Non-Biological Method for Screening Active Components against Influenza Virus from Traditional Chinese Medicine by Coupling a LC Column with Oseltamivir Molecularly Imprinted Polymers

    PubMed Central

    Yang, Ya-Jun; Li, Jian-Yong; Liu, Xi-Wang; Zhang, Ji-Yu; Liu, Yu-Rong; Li, Bing

    2013-01-01

    To develop a non-biological method for screening active components against influenza virus from traditional Chinese medicine (TCM) extraction, a liquid chromatography (LC) column prepared with oseltamivir molecularly imprinted polymer (OSMIP) was employed with LC-mass spectrometry (LC-MS). From chloroform extracts of compound TCM liquid preparation, we observed an affinitive component m/z 249, which was identified to be matrine following analysis of phytochemical literatures, OSMIP-LC column on-line of control compounds and MS/MS off-line. The results showed that matrine had similar bioactivities with OS against avian influenza virus H9N2 in vitro for both alleviating cytopathic effect and hemagglutination inhibition and that the stereostructures of these two compounds are similar while their two-dimensional structures were different. In addition, our results suggested that the bioactivities of those affinitive compounds were correlated with their chromatographic behaviors, in which less difference of the chromatographic behaviors might have more similar bioactivities. This indicates that matrine is a potential candidate drug to prevent or cure influenza for human or animal. In conclusion, the present study showed that molecularly imprinted polymers can be used as a non-biological method for screening active components against influenza virus from TCM. PMID:24386385

  15. Sulindac metabolites inhibit epidermal growth factor receptor activation and expression.

    PubMed

    Pangburn, Heather A; Kraus, Hanna; Ahnen, Dennis J; Rice, Pamela L

    2005-09-02

    Regular use of nonsteroidal anti-inflammatory drugs (NSAIDs) is associated with a decreased mortality from colorectal cancer (CRC). NSAIDs induce apoptotic cell death in colon cancer cells in vitro and inhibit growth of neoplastic colonic mucosa in vivo however, the biochemical mechanisms required for these growth inhibitory effects are not well defined. We previously reported that metabolites of the NSAID sulindac downregulate extracellular-signal regulated kinase 1/2 (ERK1/2) signaling and that this effect is both necessary and sufficient for the apoptotic effects of these drugs. The goal of this project was to specifically test the hypothesis that sulindac metabolites block activation and/or expression of the epidermal growth factor (EGF) receptor (EGFR). HT29 human colon cancer cells were treated with EGF, alone, or in the presence of sulindac sulfide or sulindac sulfone. Cells lysates were assayed by immunoblotting for phosphorylated EGFR (pEGFR, pY1068), total EGFR, phosphorylated ERK1/2 (pERK1/2), total ERK1/2, activated caspase-3, and alpha-tubulin. EGF treatment rapidly induced phosphorylation of both EGFR and ERK1/2 in HT29 colon cancer cells. Pretreatment with sulindac metabolites for 24 h blocked EGF-induced phosphorylation of both EGFR and ERK1/2 and decreased total EGFR protein expression. Under basal conditions, downregulation of pEGFR and total EGFR was detected as early as 12 h following sulindac sulfide treatment and persisted through at least 48 h. Sulindac sulfone induced downregulation of pEGFR and total EGFR was detected as early as 1 h and 24 h, respectively, following drug treatment, and persisted through at least 72 h. EGFR downregulation by sulindac metabolites was observed in three different CRC cell lines, occurred prior to the observed downregulation of pERK1/2 and induction of apoptosis by these drugs, and was not dependent of caspase activation. These results suggest that downregulation of EGFR signaling by sulindac metabolites may

  16. Clustering of 3D-Structure Similarity Based Network of Secondary Metabolites Reveals Their Relationships with Biological Activities.

    PubMed

    Ohtana, Yuki; Abdullah, Azian Azamimi; Altaf-Ul-Amin, Md; Huang, Ming; Ono, Naoaki; Sato, Tetsuo; Sugiura, Tadao; Horai, Hisayuki; Nakamura, Yukiko; Morita Hirai, Aki; Lange, Klaus W; Kibinge, Nelson K; Katsuragi, Tetsuo; Shirai, Tsuyoshi; Kanaya, Shigehiko

    2014-12-01

    Developing database systems connecting diverse species based on omics is the most important theme in big data biology. To attain this purpose, we have developed KNApSAcK Family Databases, which are utilized in a number of researches in metabolomics. In the present study, we have developed a network-based approach to analyze relationships between 3D structure and biological activity of metabolites consisting of four steps as follows: construction of a network of metabolites based on structural similarity (Step 1), classification of metabolites into structure groups (Step 2), assessment of statistically significant relations between structure groups and biological activities (Step 3), and 2-dimensional clustering of the constructed data matrix based on statistically significant relations between structure groups and biological activities (Step 4). Applying this method to a data set consisting of 2072 secondary metabolites and 140 biological activities reported in KNApSAcK Metabolite Activity DB, we obtained 983 statistically significant structure group-biological activity pairs. As a whole, we systematically analyzed the relationship between 3D-chemical structures of metabolites and biological activities. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Diversity of Secondary Metabolites from Marine Bacillus Species: Chemistry and Biological Activity

    PubMed Central

    Mondol, Muhammad Abdul Mojid; Shin, Hee Jae; Islam, Mohammad Tofazzal

    2013-01-01

    Marine Bacillus species produce versatile secondary metabolites including lipopeptides, polypeptides, macrolactones, fatty acids, polyketides, and isocoumarins. These structurally diverse compounds exhibit a wide range of biological activities, such as antimicrobial, anticancer, and antialgal activities. Some marine Bacillus strains can detoxify heavy metals through reduction processes and have the ability to produce carotenoids. The present article reviews the chemistry and biological activities of secondary metabolites from marine isolates. Side by side, the potential for application of these novel natural products from marine Bacillus strains as drugs, pesticides, carotenoids, and tools for the bioremediation of heavy metal toxicity are also discussed. PMID:23941823

  18. Strategies to enhance biologically active-secondary metabolites in cell cultures of Artemisia - current trends.

    PubMed

    Ali, Mohammad; Abbasi, Bilal Haider; Ahmad, Nisar; Khan, Haji; Ali, Gul Shad

    2017-11-01

    The genus Artemisia has been utilized worldwide due to its immense potential for protection against various diseases, especially malaria. Artemisia absinthium, previously renowned for its utilization in the popular beverage absinthe, is gaining resurgence due to its extensive pharmacological activities. Like A. annua, this species exhibits strong biological activities like antimalarial, anticancer and antioxidant. Although artemisinin was found to be the major metabolite for its antimalarial effects, several flavonoids and terpenoids are considered to possess biological activities when used alone and also to synergistically boost the bioavailability of artemisinin. However, due to the limited quantities of these metabolites in wild plants, in vitro cultures were established and strategies have been adopted to enhance medicinally important secondary metabolites in these cultures. This review elaborates on the traditional medicinal uses of Artemisia species and explains current trends to establish cell cultures of A. annua and A. absinthium for enhanced production of medicinally important secondary metabolites.

  19. Long-Chain Metabolites of Vitamin E: Metabolic Activation as a General Concept for Lipid-Soluble Vitamins?

    PubMed

    Schubert, Martin; Kluge, Stefan; Schmölz, Lisa; Wallert, Maria; Galli, Francesco; Birringer, Marc; Lorkowski, Stefan

    2018-01-12

    Vitamins E, A, D and K comprise the class of lipid-soluble vitamins. For vitamins A and D, a metabolic conversion of precursors to active metabolites has already been described. During the metabolism of vitamin E, the long-chain metabolites (LCMs) 13'-hydroxychromanol (13'-OH) and 13'-carboxychromanol (13'-COOH) are formed by oxidative modification of the side-chain. The occurrence of these metabolites in human serum indicates a physiological relevance. Indeed, effects of the LCMs on lipid metabolism, apoptosis, proliferation and inflammatory actions as well as tocopherol and xenobiotic metabolism have been shown. Interestingly, there are several parallels between the actions of the LCMs of vitamin E and the active metabolites of vitamin A and D. The recent findings that the LCMs exert effects different from that of their precursors support their putative role as regulatory metabolites. Hence, it could be proposed that the mode of action of the LCMs might be mediated by a mechanism similar to vitamin A and D metabolites. If the physiological relevance and this concept of action of the LCMs can be confirmed, a general concept of activation of lipid-soluble vitamins via their metabolites might be deduced.

  20. Antifeedant Activity of Ginkgo biloba Secondary Metabolites against Hyphantria cunea Larvae: Mechanisms and Applications

    PubMed Central

    Ren, Lili; Chen, Fang; Feng, Yuqian

    2016-01-01

    Ginkgo biloba is a typical relic plant that rarely suffers from pest hazards. This study analyzed the pattern of G. biloba pest hazards in Beijing; tested the antifeedant activity of G. biloba extracts, including ginkgo flavonoids, ginkgolide, and bilobalide, against Hyphantria cunea larvae; determined the activities of glutathione transferase (GSTs), acetylcholinesterase (AChE), carboxylesterase (CarE) and mixed-functional oxidase (MFO), in larvae after feeding on these G. biloba secondary metabolites; and screened for effective botanical antifeedants in the field. In this study, no indicators of insect infestation were found for any of the examined leaves of G. biloba; all tested secondary metabolites showed significant antifeedant activity and affected the activity of the four larval detoxifying enzymes. Ginkgolide had the highest antifeedant activity and the most significant effect on the detoxifying enzymes (P<0.05). Spraying leaves with G. biloba extracts or ginkgolide both significantly repelled H. cunea larvae in the field (P<0.05), although the former is more economical and practical. This study investigated the antifeedant activity of G. biloba secondary metabolites against H. cunea larvae, and the results provide new insights into the mechanism of G. biloba pest resistance. This study also developed new applications of G. biloba secondary metabolites for effective pest control. PMID:27214257

  1. Antifeedant Activity of Ginkgo biloba Secondary Metabolites against Hyphantria cunea Larvae: Mechanisms and Applications.

    PubMed

    Pan, Long; Ren, Lili; Chen, Fang; Feng, Yuqian; Luo, Youqing

    2016-01-01

    Ginkgo biloba is a typical relic plant that rarely suffers from pest hazards. This study analyzed the pattern of G. biloba pest hazards in Beijing; tested the antifeedant activity of G. biloba extracts, including ginkgo flavonoids, ginkgolide, and bilobalide, against Hyphantria cunea larvae; determined the activities of glutathione transferase (GSTs), acetylcholinesterase (AChE), carboxylesterase (CarE) and mixed-functional oxidase (MFO), in larvae after feeding on these G. biloba secondary metabolites; and screened for effective botanical antifeedants in the field. In this study, no indicators of insect infestation were found for any of the examined leaves of G. biloba; all tested secondary metabolites showed significant antifeedant activity and affected the activity of the four larval detoxifying enzymes. Ginkgolide had the highest antifeedant activity and the most significant effect on the detoxifying enzymes (P<0.05). Spraying leaves with G. biloba extracts or ginkgolide both significantly repelled H. cunea larvae in the field (P<0.05), although the former is more economical and practical. This study investigated the antifeedant activity of G. biloba secondary metabolites against H. cunea larvae, and the results provide new insights into the mechanism of G. biloba pest resistance. This study also developed new applications of G. biloba secondary metabolites for effective pest control.

  2. New brominated flame retardants and their metabolites as activators of the pregnane X receptor.

    PubMed

    Gramec Skledar, Darja; Tomašič, Tihomir; Carino, Adriana; Distrutti, Eleonora; Fiorucci, Stefano; Peterlin Mašič, Lucija

    2016-09-30

    The present study investigated the activities on different nuclear receptors of the new brominated flame retardants 2-ethylhexyl 2,3,4,5-tetrabromobenzoate (TBB) and bis(2-ethylhexyl) 2,3,4,5-tetrabromophthalate (TBPH), and their main carboxylic acid metabolites 2,3,4,5-tetrabromobenzoic acid (TBBA) and mono(2-ethylhexyl) tetrabromophthalate (TBMEPH). None of selected chemicals exhibited marked activity towards PPARα and PPARγ by the use of transactivation assays in HepG2 cells transfected with peroxisome proliferator-activated receptors. In contrast, selected flame retardants all exhibited potent agonist activity on pregnane X receptor (PXR), with EC50 values of 5.5μM for TBPH and 2.0μM for its metabolite TBMEPH. Molecular docking of TBPH and TBMEPH to the PXR ligand binding site revealed similar interactions, with differences only for conformation and orientation of the alkyl chains. Additionally, TBPH showed antagonist activity on PXR (IC50, 13.9μM). Moreover, there was significant up-regulation of CYP3A4 expression via PXR activation for TBB and TBPH and their metabolites. Induction of CYP3A4 might cause undesired drug-drug interactions, lower bioavailability of pharmaceutical drugs, higher formation of reactive toxic metabolites, or enhanced elimination of endogenous hormones, such as T3/T4, to lead to endocrine disruption. These data provide new and important insights into the toxicity of these new polybrominated flame retardants, TBB and TBPH, and their metabolites. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  3. [Secondary Metabolites from Marine Microorganisms. I. Secondary Metabolites from Marine Actinomycetes].

    PubMed

    Orlova, T I; Bulgakova, V G; Polin, A N

    2015-01-01

    Review represents data on new active metabolites isolated from marine actinomycetes published in 2007 to 2014. Marine actinomycetes are an unlimited source of novel secondary metabolites with various biological activities. Among them there are antibiotics, anticancer compounds, inhibitors of biochemical processes.

  4. Long-Chain Metabolites of Vitamin E: Metabolic Activation as a General Concept for Lipid-Soluble Vitamins?

    PubMed Central

    Schubert, Martin; Kluge, Stefan; Schmölz, Lisa; Wallert, Maria

    2018-01-01

    Vitamins E, A, D and K comprise the class of lipid-soluble vitamins. For vitamins A and D, a metabolic conversion of precursors to active metabolites has already been described. During the metabolism of vitamin E, the long-chain metabolites (LCMs) 13′-hydroxychromanol (13′-OH) and 13′-carboxychromanol (13′-COOH) are formed by oxidative modification of the side-chain. The occurrence of these metabolites in human serum indicates a physiological relevance. Indeed, effects of the LCMs on lipid metabolism, apoptosis, proliferation and inflammatory actions as well as tocopherol and xenobiotic metabolism have been shown. Interestingly, there are several parallels between the actions of the LCMs of vitamin E and the active metabolites of vitamin A and D. The recent findings that the LCMs exert effects different from that of their precursors support their putative role as regulatory metabolites. Hence, it could be proposed that the mode of action of the LCMs might be mediated by a mechanism similar to vitamin A and D metabolites. If the physiological relevance and this concept of action of the LCMs can be confirmed, a general concept of activation of lipid-soluble vitamins via their metabolites might be deduced. PMID:29329238

  5. Buprenorphine metabolites, buprenorphine-3-glucuronide and norbuprenorphine-3-glucuronide, are biologically active

    PubMed Central

    Brown, Sarah M.; Holtzman, Michael; Kim, Thomas; Kharasch, Evan D.

    2012-01-01

    Background The long-lasting high affinity opioid buprenorphine has complex pharmacology including ceiling effects with respect to analgesia and respiratory depression. Plasma concentrations of the major buprenorphine metabolites norbuprenorphine, buprenorphine-3-glucuronide, and norbuprenorphine-3-glucuronide approximate or exceed those of the parent drug. Buprenorphine glucuronide metabolites pharmacology is undefined. This investigation determined binding and pharmacological activity of the two glucuronide metabolites, and in comparison with buprenorphine and norbuprenorphine. Methods Competitive inhibition of radioligand binding to human mu, kappa, delta opioid and nociceptin receptors was used to determine glucuronide binding affinities for these receptors. Common opiate effects were assessed in vivo in Swiss Webster mice. Antinociception was assessed using a tail-flick assay, respiratory effects were measured using unrestrained whole-body plethysmography, and sedation was assessed by inhibition of locomotion measured by open-field testing. Results Buprenorphine-3-glucuronide had high affinity for human mu (Ki = 4.9±2.7 pM), delta (Ki = 270±0.4 nM), and nociceptin (Ki = 36±0.3 μM) but not kappa receptors. Norbuprenorphine-3-glucuronide had affinity for human kappa (Ki = 300±0.5 nM) and nociceptin (Ki= 18±0.2 μM) but not mu or delta receptors. At the dose tested, buprenorphine-3-glucuronide had a small antinociceptive effect. Neither glucuronide had significant effects on respiratory rate, but norbuprenorphine-3-glucuronide decreased tidal volume. Norbuprenorphine-3-glucuronide also caused sedation. Conclusions Both glucuronide metabolites of buprenorphine are biologically active at doses relevant to metabolite exposures which occur after buprenorphine. Activity of the glucuronides may contribute to the overall pharmacology of buprenorphine. PMID:22037640

  6. Bisphenol A and its analogs: Do their metabolites have endocrine activity?

    PubMed

    Gramec Skledar, Darja; Peterlin Mašič, Lucija

    2016-10-01

    Structural analogs of bisphenol A are commonly used as its alternatives in industrial and commercial applications. Nevertheless, the question arises whether the use of other bisphenols is justified as replacements for bisphenol A in mass production of plastic materials. To evaluate the influence of metabolic reactions on endocrine activities of bisphenols, we conducted a systematic review of the literature. Knowledge about the metabolic pathways and enzymes involved in metabolic biotransformations is essential for understanding and predicting mechanisms of toxicity. Bisphenols are metabolized predominantly by the glucuronidation reaction, which is considered their most important detoxification pathway, as based on current knowledge, glucuronides do not have activity on endocrine receptors. In contrast, several oxidative metabolites of bisphenols with enhanced endocrine activities are presented, and these findings indicate that oxidative metabolites of bisphenols can still have endocrine activities in humans. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Pandemic pharmaceutical dosing effects on wastewater treatment: no adaptation of activated sludge bacteria to degrade the antiviral drug oseltamivir (Tamiflu®) and loss of nutrient removal performance.

    PubMed

    Slater, Frances R; Singer, Andrew C; Turner, Susan; Barr, Jeremy J; Bond, Philip L

    2011-02-01

    The 2009-2010 influenza pandemic saw many people treated with antivirals and antibiotics. High proportions of both classes of drugs are excreted and enter wastewater treatment plants (WWTPs) in biologically active forms. To date, there has been no study into the potential for influenza pandemic-scale pharmaceutical use to disrupt WWTP function. Furthermore, there is currently little indication as to whether WWTP microbial consortia can degrade antiviral neuraminidase inhibitors when exposed to pandemic-scale doses. In this study, we exposed an aerobic granular sludge sequencing batch reactor, operated for enhanced biological phosphorus removal (EBPR), to a simulated influenza-pandemic dosing of antibiotics and antivirals for 8 weeks. We monitored the removal of the active form of Tamiflu(®), oseltamivir carboxylate (OC), bacterial community structure, granule structure and changes in EBPR and nitrification performance. There was little removal of OC by sludge and no evidence that the activated sludge community adapted to degrade OC. There was evidence of changes to the bacterial community structure and disruption to EBPR and nitrification during and after high-OC dosing. This work highlights the potential for the antiviral contamination of receiving waters and indicates the risk of destabilizing WWTP microbial consortia as a result of high concentrations of bioactive pharmaceuticals during an influenza pandemic. © 2010 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  8. Antimalarial Activity of Plant Metabolites.

    PubMed

    Pan, Wen-Hui; Xu, Xin-Ya; Shi, Ni; Tsang, Siu Wai; Zhang, Hong-Jie

    2018-05-06

    Malaria, as a major global health problem, continues to affect a large number of people each year, especially those in developing countries. Effective drug discovery is still one of the main efforts to control malaria. As natural products are still considered as a key source for discovery and development of therapeutic agents, we have evaluated more than 2000 plant extracts against Plasmodium falciparum . As a result, we discovered dozens of plant leads that displayed antimalarial activity. Our phytochemical study of some of these plant extracts led to the identification of several potent antimalarial compounds. The prior comprehensive review article entitled “Antimalarial activity of plant metabolites” by Schwikkard and Van Heerden (2002) reported structures of plant-derived compounds with antiplasmodial activity and covered literature up to the year 2000. As a continuation of this effort, the present review covers the antimalarial compounds isolated from plants, including marine plants, reported in the literature from 2001 to the end of 2017. During the span of the last 17 years, 175 antiplasmodial compounds were discovered from plants. These active compounds are organized in our review article according to their plant families. In addition, we also include ethnobotanical information of the antimalarial plants discussed.

  9. Understanding the cross-resistance of oseltamivir to H1N1 and H5N1 influenza A neuraminidase mutations using multidimensional computational analyses

    PubMed Central

    Singh, Ashona; Soliman, Mahmoud E

    2015-01-01

    This study embarks on a comprehensive description of the conformational contributions to resistance of neuraminidase (N1) in H1N1 and H5N1 to oseltamivir, using comparative multiple molecular dynamic simulations. The available data with regard to elucidation of the mechanism of resistance as a result of mutations in H1N1 and H5N1 neuraminidases is not well established. Enhanced post-dynamic analysis, such as principal component analysis, solvent accessible surface area, free binding energy calculations, and radius of gyration were performed to gain a precise insight into the binding mode and origin of resistance of oseltamivir in H1N1 and H5N1 mutants. Three significant features reflecting resistance in the presence of mutations H274Y and I222K, of the protein complexed with the inhibitor are: reduced flexibility of the α-carbon backbone; an improved ΔEele of ~15 (kcal/mol) for H1N1 coupled with an increase in ΔGsol (~13 kcal/mol) from wild-type to mutation; a low binding affinity in comparison with the wild-type of ~2 (kcal/mol) and ~7 (kcal/mol) with respect to each mutation for the H5N1 systems; and reduced hydrophobicity of the overall surface structure due to an impaired hydrogen bonding network. We believe the results of this study will ultimately provide a useful insight into the structural landscape of neuraminidase-associated binding of oseltamivir. Furthermore, the results can be used in the design and development of potent inhibitors of neuraminidases. PMID:26257512

  10. Understanding the cross-resistance of oseltamivir to H1N1 and H5N1 influenza A neuraminidase mutations using multidimensional computational analyses.

    PubMed

    Singh, Ashona; Soliman, Mahmoud E

    2015-01-01

    This study embarks on a comprehensive description of the conformational contributions to resistance of neuraminidase (N1) in H1N1 and H5N1 to oseltamivir, using comparative multiple molecular dynamic simulations. The available data with regard to elucidation of the mechanism of resistance as a result of mutations in H1N1 and H5N1 neuraminidases is not well established. Enhanced post-dynamic analysis, such as principal component analysis, solvent accessible surface area, free binding energy calculations, and radius of gyration were performed to gain a precise insight into the binding mode and origin of resistance of oseltamivir in H1N1 and H5N1 mutants. Three significant features reflecting resistance in the presence of mutations H274Y and I222K, of the protein complexed with the inhibitor are: reduced flexibility of the α-carbon backbone; an improved ΔEele of ~15 (kcal/mol) for H1N1 coupled with an increase in ΔGsol (~13 kcal/mol) from wild-type to mutation; a low binding affinity in comparison with the wild-type of ~2 (kcal/mol) and ~7 (kcal/mol) with respect to each mutation for the H5N1 systems; and reduced hydrophobicity of the overall surface structure due to an impaired hydrogen bonding network. We believe the results of this study will ultimately provide a useful insight into the structural landscape of neuraminidase-associated binding of oseltamivir. Furthermore, the results can be used in the design and development of potent inhibitors of neuraminidases.

  11. A Potential Biofilm Metabolite Signature for Caries Activity - A Pilot Clinical Study

    PubMed Central

    Zandona, F; Soini, HA; Novotny, MV; Santiago, E; Eckert, GJ; Preisser, JS; Benecha, HK; Arthur, RA; Zero, DT

    2016-01-01

    Background This study's aim was to compare the dental biofilm metabolite-profile of caries-active (N=11) or caries-free (N=4) children by gas chromatography-mass spectrometry (GC/MS) analyses. Methods Samples collected after overnight fasting, with or without a previous glucose rinse, were combined for each child based on the caries status of the site, re-suspended in ethanol and analyzed by GC/MS. Results Biofilm from caries-active sites exhibited a different chromatographic profile compared to caries-free sites. Qualitative and quantitative analysis suggested a special cluster of branched alcohols and esters present at substantially higher intensity in biofilms of caries-active sites. Conclusions This pilot study indicates that there are metabolites present in the biofilm which have the potential to provide a characteristic metabolomics signature for caries activity. PMID:27885354

  12. Intracellular studies of the nucleoside reverse transcriptase inhibitor active metabolites: a review.

    PubMed

    Rodriguez Orengo, J F; Santana, J; Febo, I; Diaz, C; Rodriguez, J L; Garcia, R; Font, E; Rosario, O

    2000-03-01

    Nucleoside reverse transcriptase inhibitors (NRTIs) plasma concentrations do not correlate with clinical efficacy or toxicity. These agents need to be phosphorylated to become active against HIV-infection. Thus, the characterization of the NRTIs intracellular metabolite pharmacological parameters will provide a better understanding that could lead to the development of more rational dose regimens in the HIV-infected population. Furthermore, intracellular measurements of NRTIs may provide a better marker with respect to clinical efficacy and toxicity than plasma concentrations. Thus, in this article we review the latest information regarding the intracellular pharmacological parameters of zidovudine (ZDV) and lamivudine (3TC) active metabolites in HIV-infected patients including the results from our recent clinical studies. We will start the discussion with ZDV and 3TC clinical efficacy, followed by systemic pharmacokinetics studies. We will then discuss the in vitro and in vivo intracellular studies with particular emphasis in the method development to measure these metabolites and we will conclude with the most current data from our clinical trials.

  13. Marine Invertebrate Metabolites with Anticancer Activities: Solutions to the “Supply Problem”

    PubMed Central

    Gomes, Nelson G. M.; Dasari, Ramesh; Chandra, Sunena; Kiss, Robert; Kornienko, Alexander

    2016-01-01

    Marine invertebrates provide a rich source of metabolites with anticancer activities and several marine-derived agents have been approved for the treatment of cancer. However, the limited supply of promising anticancer metabolites from their natural sources is a major hurdle to their preclinical and clinical development. Thus, the lack of a sustainable large-scale supply has been an important challenge facing chemists and biologists involved in marine-based drug discovery. In the current review we describe the main strategies aimed to overcome the supply problem. These include: marine invertebrate aquaculture, invertebrate and symbiont cell culture, culture-independent strategies, total chemical synthesis, semi-synthesis, and a number of hybrid strategies. We provide examples illustrating the application of these strategies for the supply of marine invertebrate-derived anticancer agents. Finally, we encourage the scientific community to develop scalable methods to obtain selected metabolites, which in the authors’ opinion should be pursued due to their most promising anticancer activities. PMID:27213412

  14. The formation of estrogen-like tamoxifen metabolites and their influence on enzyme activity and gene expression of ADME genes.

    PubMed

    Johänning, Janina; Kröner, Patrick; Thomas, Maria; Zanger, Ulrich M; Nörenberg, Astrid; Eichelbaum, Michel; Schwab, Matthias; Brauch, Hiltrud; Schroth, Werner; Mürdter, Thomas E

    2018-03-01

    Tamoxifen, a standard therapy for breast cancer, is metabolized to compounds with anti-estrogenic as well as estrogen-like action at the estrogen receptor. Little is known about the formation of estrogen-like metabolites and their biological impact. Thus, we characterized the estrogen-like metabolites tamoxifen bisphenol and metabolite E for their metabolic pathway and their influence on cytochrome P450 activity and ADME gene expression. The formation of tamoxifen bisphenol and metabolite E was studied in human liver microsomes and Supersomes™. Cellular metabolism and impact on CYP enzymes was analyzed in upcyte® hepatocytes. The influence of 5 µM of tamoxifen, anti-estrogenic and estrogen-like metabolites on CYP activity was measured by HPLC MS/MS and on ADME gene expression using RT-PCR analyses. Metabolite E was formed from tamoxifen by CYP2C19, 3A and 1A2 and from desmethyltamoxifen by CYP2D6, 1A2 and 3A. Tamoxifen bisphenol was mainly formed from (E)- and (Z)-metabolite E by CYP2B6 and CYP2C19, respectively. Regarding phase II metabolism, UGT2B7, 1A8 and 1A3 showed highest activity in glucuronidation of tamoxifen bisphenol and metabolite E. Anti-estrogenic metabolites (Z)-4-hydroxytamoxifen, (Z)-endoxifen and (Z)-norendoxifen inhibited the activity of CYP2C enzymes while tamoxifen bisphenol consistently induced CYPs similar to rifampicin and phenobarbital. On the transcript level, highest induction up to 5.6-fold was observed for CYP3A4 by tamoxifen, (Z)-4-hydroxytamoxifen, tamoxifen bisphenol and (E)-metabolite E. Estrogen-like tamoxifen metabolites are formed in CYP-dependent reactions and are further metabolized by glucuronidation. The induction of CYP activity by tamoxifen bisphenol and the inhibition of CYP2C enzymes by anti-estrogenic metabolites may lead to drug-drug-interactions.

  15. The antibacterial activity of syringopicroside, its metabolites and natural analogues from Syringae Folium.

    PubMed

    Zhou, Zhengyuan; Han, Na; Liu, Zhihui; Song, Zehai; Wu, Peng; Shao, Jingxuan; Zhang, Jia Ming; Yin, Jun

    2016-04-01

    In the present study, the in vitro antibacterial activity of an effective fraction (ESF) from Syringae Folium (SF) on Methicillin-resistant Staphylococcus aureus (MRSA) was evaluated and then its in vivo activity was evaluated by using the MRSA-infected mouse peritonitis model. The ESF showed a significant in vitro and in vivo activity on decreasing the Minimum Inhibitory Concentrations (MICs) and increasing the survival rate of mouse from 42.8% to 100%. Six iridoid glucosides (IGs) of ESF were characterized by UPLC-TOF-MS method and also isolated by column chromatography. Most of them showed in vitro anti MRSA activity. Syringopicroside (Sy), the major compound of IGs, was found to increase the survival rate from 42.8% to 92.8% of the MRSA-infected mouse, which revealed Sy is also the main active components of ESF. In order to know why the effect of oral administration of SF is better than its injections in clinic and the metabolites of Sy, seven metabolites of Sy were isolated from rat urine and identified on the basis of NMR and MS spectra. Most of metabolites possessed stronger in vitro anti-MRSA activity than that of Sy, which furtherly proved the clinical result. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Pharmacologically active plant metabolites as survival strategy products.

    PubMed

    Attardo, C; Sartori, F

    2003-01-01

    The fact that plant organisms produce chemical substances that are able to positively or negatively interfere with the processes which regulate human life has been common knowledge since ancient times. One of the numerous possible examples in the infusion of Conium maculatum, better known as Hemlock, a plant belonging to the family umbelliferae, used by the ancient Egyptians to cure skin diseases. The current official pharmacopoeia includes various chemical substances produced by secondary plant metabolisms. For example, the immunosuppressive drugs used to prevent organ transplant rejection and the majority of antibiotics are metabolites produced by fungal organisms, pilocarpin, digitalis, strophantus, salicylic acid and curare are examples of plant organism metabolites. For this reason, there has been an increase in research into plants, based on information on their medicinal use in the areas where they grow. The study of plants in relation to local culture and traditions is known as "ethnobotany". Careful study of the behaviour of sick animals has also led to the discovery of medicinal plants. The study of this subject is known as "zoopharmacognosy". The aim of this article is to discuss the fact that "ad hoc" production of such chemical substances, defined as "secondary metabolites", is one of the modes in which plant organisms respond to unfavourable environmental stimuli, such as an attack by predatory phytophagous animals or an excessive number of plant individuals, even of the same species, in a terrain. In the latter case, the plant organisms produce toxic substances, called "allelopathic" which limit the growth of other individuals. "Secondary metabolites" are produced by metabolic systems that are shunts of the primary systems which, when required, may be activated from the beginning, or increased to the detriment of others. The study of the manner in which such substances are produced is the subject of a new branch of learning called "ecological

  17. Urinary Estrogen Metabolites, Active and Sedentary Behaviors, and Breast Cancer Risk

    Cancer.gov

    A cross-sectional study of approximately 600 postmenopausal controls in the Breast Cancer Case-Control Study in Poland to assess urinary estrogen metabolites in relation to accelerometer-based measures of active and sedentary behaviors

  18. Green Tea Catechin Metabolites Exert Immunoregulatory Effects on CD4(+) T Cell and Natural Killer Cell Activities.

    PubMed

    Kim, Yoon Hee; Won, Yeong-Seon; Yang, Xue; Kumazoe, Motofumi; Yamashita, Shuya; Hara, Aya; Takagaki, Akiko; Goto, Keiichi; Nanjo, Fumio; Tachibana, Hirofumi

    2016-05-11

    Tea catechins, such as (-)-epigallocatechin-3-O-gallate (EGCG), have been shown to effectively enhance immune activity and prevent cancer, although the underlying mechanism is unclear. Green tea catechins are instead converted to catechin metabolites in the intestine. Here, we show that these green tea catechin metabolites enhance CD4(+) T cell activity as well as natural killer (NK) cell activity. Our data suggest that the absence of a 4'-hydroxyl on this phenyl group (B ring) is important for the effect on immune activity. In particular, 5-(3',5'-dihydroxyphenyl)-γ-valerolactone (EGC-M5), a major metabolite of EGCG, not only increased the activity of CD4(+) T cells but also enhanced the cytotoxic activity of NK cells in vivo. These data suggest that EGC-M5 might show immunostimulatory activity.

  19. Chemopreventive Activities of Sulforaphane and Its Metabolites in Human Hepatoma HepG2 Cells.

    PubMed

    Liu, Peng; Wang, Wei; Zhou, Zhigang; Smith, Andrew J O; Bowater, Richard P; Wormstone, Ian Michael; Chen, Yuqiong; Bao, Yongping

    2018-05-09

    Sulforaphane (SFN) exhibits chemopreventive effects through various mechanisms. However, few studies have focused on the bioactivities of its metabolites. Here, three metabolites derived from SFN were studied, known as sulforaphane glutathione, sulforaphane cysteine and sulforaphane- N -acetylcysteine. Their effects on cell viability, DNA damage, tumorigenicity, cell migration and adhesion were measured in human hepatoma HepG2 cells, and their anti-angiogenetic effects were determined in a 3D co-culture model of human umbilical vein endothelial cells (HUVECs) and pericytes. Results indicated that these metabolites at high doses decreased cancer cell viability, induced DNA damage and inhibited motility, and impaired endothelial cell migration and tube formation. Additionally, pre-treatment with low doses of SFN metabolites protected against H₂O₂ challenge. The activation of the nuclear factor E2-related factor 2 (Nrf2)-antioxidant response element (ARE) pathway and the induction of intracellular glutathione (GSH) played an important role in the cytoprotective effects of SFN metabolites. In conclusion, SFN metabolites exhibited similar cytotoxic and cytoprotective effects to SFN, which proves the necessity to study the mechanisms of action of not only SFN but also of its metabolites. Based on the different tissue distribution profiles of these metabolites, the most relevant chemical forms can be selected for targeted chemoprevention.

  20. Baicalin, a metabolite of baicalein with antiviral activity against dengue virus

    PubMed Central

    Moghaddam, Ehsan; Teoh, Boon-Teong; Sam, Sing-Sin; Lani, Rafidah; Hassandarvish, Pouya; Chik, Zamri; Yueh, Andrew; Abubakar, Sazaly; Zandi, Keivan

    2014-01-01

    Baicalin, a flavonoid derived from Scutellaria baicalensis, is the main metabolite of baicalein released following administration in different animal models and human. We previously reported the antiviral activity of baicalein against dengue virus (DENV). Here, we examined the anti-DENV properties of baicalin in vitro, and described the inhibitory potentials of baicalin at different steps of DENV-2 (NGC strain) replication. Our in vitro antiviral experiments showed that baicalin inhibited virus replication at IC50 = 13.5 ± 0.08 μg/ml with SI = 21.5 following virus internalization by Vero cells. Baicalin exhibited virucidal activity against DENV-2 extracellular particles at IC50 = 8.74 ± 0.08 μg/ml and showed anti-adsorption effect with IC50 = 18.07 ± 0.2 μg/ml. Our findings showed that baicalin as the main metabolite of baicalein exerting in vitro anti-DENV activity. Further investigations on baicalein and baicalin to deduce its antiviral therapeutic effects are warranted. PMID:24965553

  1. Microbiome-Derived Tryptophan Metabolites and Their Aryl Hydrocarbon Receptor-Dependent Agonist and Antagonist Activities

    PubMed Central

    Jin, Un-Ho; Lee, Syng-Ook; Sridharan, Gautham; Lee, Kyongbum; Davidson, Laurie A.; Jayaraman, Arul; Chapkin, Robert S.; Alaniz, Robert

    2014-01-01

    The tryptophan metabolites indole, indole-3-acetate, and tryptamine were identified in mouse cecal extracts and fecal pellets by mass spectrometry. The aryl hydrocarbon receptor (AHR) agonist and antagonist activities of these microbiota-derived compounds were investigated in CaCo-2 intestinal cells as a model for understanding their interactions with colonic tissue, which is highly aryl hydrocarbon (Ah)–responsive. Activation of Ah-responsive genes demonstrated that tryptamine and indole 3-acetate were AHR agonists, whereas indole was an AHR antagonist that inhibited TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin)–induced CYP1A1 expression. In contrast, the tryptophan metabolites exhibited minimal anti-inflammatory activities, whereas TCDD decreased phorbol ester-induced CXCR4 [chemokine (C-X-C motif) receptor 4] gene expression, and this response was AHR dependent. These results demonstrate that the tryptophan metabolites indole, tryptamine, and indole-3-acetate modulate AHR-mediated responses in CaCo-2 cells, and concentrations of indole that exhibit AHR antagonist activity (100–250 μM) are detected in the intestinal microbiome. PMID:24563545

  2. [Optimising azathioprine treatment: determination of thiopurine methyltransferase activity and thiopurine metabolites].

    PubMed

    Alvarez Beltran, M; Infante Pina, D; Tormo Carnicé, R; Segarra Cantón, O; Redecillas Ferreiro, S

    2009-02-01

    Individualised doses of azathioprine (AZA) may be prescribed by monitoring the levels of the enzyme thiopurine methyltransferase (TPMT). The measurements of thiopurine metabolites of AZA, 6-thioguanine (6-TGN) and 6-methylmercaptopurine (6-MMP), have also been reported as new markers of AZA activity. To describe TPMT phenotype in our population and to establish a relationship between thiopurine metabolites,and therapeutic activity and adverse effects. Data on TPMT were retrospectively collected from 107 patients, and 6-TGN and 6-MMP levels in 18 patients currently on treatment with AZA (Crohn's disease 5, ulcerative colitis 5, autoimmune hepatitis 5). Mean value of TPMT was 20.19U/ml. None of the patients had a TPMT activity<5U/ml. Of the 18 patients on treatment, 13 showed sub-therapeutic levels of 6-TGN (<235pmol/8x10(8) red blood cells). Clinical remission was maintained in 45% of patients. Mean levels of 6-TGN in patients with clinical remission were 259pmol/8x10(8) red blood cells versus 209pmol/8x10(8) red blood cells in non-responders (p=0.37). There was an inverse relationship (r=-0.28) between TPMT and 6-TGN levels. Toxic effects occurred in 6 of 18 patients, with leukopenia in 5 and hyperamylasemia in 1. Determination of TPMT and monitoring of thiopurine metabolites allows AZA treatment to be optimised, although further studies are necessary to establish therapeutic effectiveness and toxicity ranges.

  3. Efficacy of Clarithromycin-Naproxen-Oseltamivir Combination in the Treatment of Patients Hospitalized for Influenza A(H3N2) Infection: An Open-label Randomized, Controlled, Phase IIb/III Trial.

    PubMed

    Hung, Ivan F N; To, Kelvin K W; Chan, Jasper F W; Cheng, Vincent C C; Liu, Kevin S H; Tam, Anthony; Chan, Tuen-Ching; Zhang, Anna Jinxia; Li, Patrick; Wong, Tin-Lun; Zhang, Ricky; Cheung, Michael K S; Leung, William; Lau, Johnson Y N; Fok, Manson; Chen, Honglin; Chan, Kwok-Hung; Yuen, Kwok-Yung

    2017-05-01

    Influenza causes excessive hospitalizations and deaths. The study assessed the efficacy and safety of a clarithromycin-naproxen-oseltamivir combination for treatment of serious influenza. From February to April 2015, we conducted a prospective open-label, randomized, controlled trial. Adult patients hospitalized for A(H3N2) influenza were randomly assigned to a 2-day combination of clarithromycin 500 mg, naproxen 200 mg, and oseltamivir 75 mg twice daily, followed by 3 days of oseltamivir or to oseltamivir 75 mg twice daily without placebo for 5 days as a control method (1:1). The primary end point was 30-day mortality. The secondary end points were 90-day mortality, serial nasopharyngeal aspirate (NPA) virus titer, percentage of neuraminidase-inhibitor-resistant A(H3N2) virus (NIRV) quasispecies, pneumonia severity index (PSI), and duration of hospital stay. Among the 217 patients with influenza A(H3N2) enrolled, 107 were randomly assigned to the combination treatment. The median age was 80 years, and 53.5% were men. Adverse events were uncommon. Ten patients died during the 30-day follow-up. The combination treatment was associated with lower 30-day mortality (P = .01), less frequent high dependency unit admission (P = .009), and shorter hospital stay (P < .0001). The virus titer and PSI (days 1-3; P < .01) and the NPA specimens with NIRV quasispecies ≥ 5% (days 1-2; P < .01) were significantly lower in the combination treatment group. Multivariate analysis showed that combination treatment was the only independent factor associated with lower 30-day mortality (OR, 0.06; 95% CI, 0.004-0.94; P = .04). Combination treatment reduced both 30- and 90-day mortality and length of hospital stay. Further study of the antiviral and immunomodulatory effects of this combination treatment of severe influenza is warranted. BioMed Central; No.: ISRCTN11273879 DOI 10.1186/ISRCTN11273879; URL: www.isrctn.com/ISRCTN11273879. Copyright © 2016 American College

  4. Identification and Characterization of CINPA1 Metabolites Facilitates Structure-Activity Studies of the Constitutive Androstane Receptor

    PubMed Central

    Cherian, Milu T.; Yang, Lei; Chai, Sergio C.; Lin, Wenwei

    2016-01-01

    The constitutive androstane receptor (CAR) regulates the expression of genes involved in drug metabolism and other processes. A specific inhibitor of CAR is critical for modulating constitutive CAR activity. We recently described a specific small-molecule inhibitor of CAR, CINPA1 (ethyl (5-(diethylglycyl)-10,11-dihydro-5H-dibenzo[b,f]azepin-3-yl)carbamate), which is capable of reducing CAR-mediated transcription by changing the coregulator recruitment pattern and reducing CAR occupancy at the promoter regions of its target genes. In this study, we showed that CINPA1 is converted to two main metabolites in human liver microsomes. By using cell-based reporter gene and biochemical coregulator recruitment assays, we showed that although metabolite 1 was very weak in inhibiting CAR function and disrupting CAR-coactivator interaction, metabolite 2 was inactive in this regard. Docking studies using the CAR ligand-binding domain structure showed that although CINPA1 and metabolite 1 can bind in the CAR ligand-binding pocket, metabolite 2 may be incapable of the molecular interactions required for binding. These results indicate that the metabolites of CINPA1 may not interfere with the action of CINPA1. We also used in vitro enzyme assays to identify the cytochrome P450 enzymes responsible for metabolizing CINPA1 in human liver microsomes and showed that CINPA1 was first converted to metabolite 1 by CYP3A4 and then further metabolized by CYP2D6 to metabolite 2. Identification and characterization of the metabolites of CINPA1 enabled structure-activity relationship studies of this family of small molecules and provided information to guide in vivo pharmacological studies. PMID:27519550

  5. Effect of double dose oseltamivir on clinical and virological outcomes in children and adults admitted to hospital with severe influenza: double blind randomised controlled trial

    PubMed Central

    2013-01-01

    Objective To investigate the validity of recommendations in treatment guidelines to use higher than approved doses of oseltamivir in patients with severe influenza. Design Double blind randomised trial. Setting Thirteen hospitals in Indonesia, Singapore, Thailand, and Vietnam. Participants Patients aged ≥1 year admitted to hospital with confirmed severe influenza. Interventions Oral oseltamivir at double dose (150 mg twice a day/paediatric equivalent) versus standard dose (75 mg twice a day/paediatric equivalent). Main outcome measure Viral status according to reverse transcriptase polymerase chain reaction (RT-PCR) for influenza RNA in nasal and throat swabs on day five. Results Of 326 patients (including 246 (75.5%) children aged <15), 165 and 161 were randomised to double or standard dose oseltamivir, respectively. Of these, 260 (79.8%) were infected with influenza virus A (133 (40.8%) with A/H3N2, 72 (22.1%) with A/H1N1-pdm09, 38 (11.7%) with seasonal A/H1N1, 17 (5.2%) with A/H5N1) and 53 (16.2%) with influenza virus B. A further 3.9% (13) were false positive by rapid antigen test (negative by RT-PCR and no rise in convalescent haemagglutination inhibition titers). Similar proportions of patients were negative for RT-PCR on day five of treatment: 115/159 (72.3%, 95% confidence interval 64.9% to 78.7%) double dose recipients versus 105/154 (68.2%, 60.5% to 75.0%) standard dose recipients; difference 4.2% (−5.9 to 14.2); P=0.42. No differences were found in clearance of virus in subgroup analyses by virus type/subtype, age, and duration of illness before randomisation. Mortality was similar: 12/165 (7.3%, 4.2% to 12.3%) in double dose recipients versus 9/161 (5.6%, 3.0% to 10.3%) in standard dose recipients. No differences were found between double and standard dose arms in median days on supplemental oxygen (3 (interquartile range 2-5) v 3.5 (2-7)), in intensive care (4.5 (3-6) v 5 (2-11), and on mechanical ventilation (2.5 (1-16) v 8 (1-16)), respectively

  6. Activation of the reticulothalamic cholinergic pathway by the major metabolites of aniracetam.

    PubMed

    Nakamura, K; Shirane, M

    1999-09-10

    The aim of the study was to further investigate the effects of aniracetam, a cognition enhancer, and its metabolites on the brain cholinergic system. We measured choline acetyltransferase activity and acetylcholine release using in vivo brain microdialysis in stroke-prone spontaneously hypertensive rats (SHRSP). The enzyme activity in the pons-midbrain and hippocampus, and basal acetylcholine release in the nucleus reticularis thalami were lower in SHRSP than in age-matched Wistar Kyoto rats, indicating central cholinergic deficits in SHRSP. Repeated treatment of aniracetam (50 mg/kg p.o. x 11 for 6 days) preferentially increased the enzyme activity in the thalamus, whereas decreased it in the striatum. Among the metabolites of aniracetam, local perfusion of N-anisoyl-gamma-aminobutyric acid (GABA, 0.1 and/or 1 microM) and p-anisic acid (1 microM) into the nucleus reticularis thalami, dorsal hippocampus and prefrontal cortex of SHRSP produced a significant but delayed increase of acetylcholine release. We failed, however, to find any effect of aniracetam itself. A direct injection of N-anisoyl-GABA (1 nmol) into the pedunculopontine tegmental nucleus of SHRSP enhanced the release in the nucleus reticularis thalami. Thus, these data prove that aniracetam can facilitate central cholinergic neurotransmission via both metabolites. Based on its pharmacokinetic profile, N-anisoyl-GABA may contribute to the clinical effects of aniracetam, mainly by acting on the reticulothalamic cholinergic pathway.

  7. Amplified and in situ detection of redox-active metabolite using a biobased redox capacitor.

    PubMed

    Kim, Eunkyoung; Gordonov, Tanya; Bentley, William E; Payne, Gregory F

    2013-02-19

    Redox cycling provides a mechanism to amplify electrochemical signals for analyte detection. Previous studies have shown that diverse mediators/shuttles can engage in redox-cycling reactions with a biobased redox capacitor that is fabricated by grafting redox-active catechols onto a chitosan film. Here, we report that redox cycling with this catechol-chitosan redox capacitor can amplify electrochemical signals for detecting a redox-active bacterial metabolite. Specifically, we studied the redox-active bacterial metabolite pyocyanin that is reported to be a virulence factor and signaling molecule for the opportunistic pathogen P. aeruginosa. We demonstrate that redox cycling can amplify outputs from various electrochemical methods (cyclic voltammetry, chronocoulometry, and differential pulse voltammetry) and can lower the detection limit of pyocyanin to 50 nM. Further, the compatibility of this biobased redox capacitor allows the in situ monitoring of the production of redox-active metabolites (e.g., pyocyanin) during the course of P. aeruginosa cultivation. We anticipate that the amplified output of redox-active virulence factors should permit an earlier detection of life-threatening infections by the opportunistic pathogen P. aeruginosa while the "bio-compatibility" of this measurement approach should facilitate in situ study of the spatiotemporal dynamics of bacterial redox signaling.

  8. Transporter-Mediated Disposition, Clinical Pharmacokinetics and Cholestatic Potential of Glyburide and Its Primary Active Metabolites.

    PubMed

    Li, Rui; Bi, Yi-An; Vildhede, Anna; Scialis, Renato J; Mathialagan, Sumathy; Yang, Xin; Marroquin, Lisa D; Lin, Jian; Varma, Manthena V S

    2017-07-01

    Glyburide is widely used for the treatment of type 2 diabetes. We studied the mechanisms involved in the disposition of glyburide and its pharmacologically active hydroxy metabolites M1 and M2b and evaluated their clinical pharmacokinetics and the potential role in glyburide-induced cholestasis employing physiologically based pharmacokinetic (PBPK) modeling. Transport studies of parent and metabolites in human hepatocytes and transfected cell systems imply hepatic uptake mediated by organic anion-transporting polypeptides. Metabolites are also subjected to basolateral and biliary efflux by P-glycoprotein, breast cancer resistance protein, and multidrug resistance-associated proteins, and are substrates to renal organic anion transporter 3. A PBPK model in combination with a Bayesian approach was developed considering the identified disposition mechanisms. The model reasonably described plasma concentration time profiles and urinary recoveries of glyburide and the metabolites, implying the role of multiple transport processes in their pharmacokinetics. Predicted free liver concentrations of the parent (∼30-fold) and metabolites (∼4-fold) were higher than their free plasma concentrations. Finally, all three compounds showed bile salt export pump inhibition in vitro; however, significant in vivo inhibition was not apparent for any compound on the basis of a predicted unbound liver exposure-response effect model using measured in vitro IC 50 values. In conclusion, this study demonstrates the important role of multiple drug transporters in the disposition of glyburide and its active metabolites, suggesting that variability in the function of these processes may lead to pharmacokinetic variability in the parent and the metabolites, potentially translating to pharmacodynamic variability. Copyright © 2017 by The American Society for Pharmacology and Experimental Therapeutics.

  9. Human Metabolites of Cannabidiol: A Review on Their Formation, Biological Activity, and Relevance in Therapy

    PubMed Central

    Ujváry, István; Hanuš, Lumír

    2016-01-01

    Abstract Cannabidiol (CBD), the main nonpsychoactive constituent of Cannabis sativa, has shown a wide range of therapeutically promising pharmacological effects either as a sole drug or in combination with other drugs in adjunctive therapy. However, the targets involved in the therapeutic effects of CBD appear to be elusive. Furthermore, scarce information is available on the biological activity of its human metabolites which, when formed in pharmacologically relevant concentration, might contribute to or even account for the observed therapeutic effects. The present overview summarizes our current knowledge on the pharmacokinetics and metabolic fate of CBD in humans, reviews studies on the biological activity of CBD metabolites either in vitro or in vivo, and discusses relevant drug–drug interactions. To facilitate further research in the area, the reported syntheses of CBD metabolites are also catalogued. PMID:28861484

  10. Human Metabolites of Cannabidiol: A Review on Their Formation, Biological Activity, and Relevance in Therapy.

    PubMed

    Ujváry, István; Hanuš, Lumír

    2016-01-01

    Cannabidiol (CBD), the main nonpsychoactive constituent of Cannabis sativa , has shown a wide range of therapeutically promising pharmacological effects either as a sole drug or in combination with other drugs in adjunctive therapy. However, the targets involved in the therapeutic effects of CBD appear to be elusive. Furthermore, scarce information is available on the biological activity of its human metabolites which, when formed in pharmacologically relevant concentration, might contribute to or even account for the observed therapeutic effects. The present overview summarizes our current knowledge on the pharmacokinetics and metabolic fate of CBD in humans, reviews studies on the biological activity of CBD metabolites either in vitro or in vivo , and discusses relevant drug-drug interactions. To facilitate further research in the area, the reported syntheses of CBD metabolites are also catalogued.

  11. An Antiestrogenic Activity Score for tamoxifen and its metabolites is associated with breast cancer outcome

    PubMed Central

    Alexi, X.; van Werkhoven, E.; Madlensky, L.; Natarajan, L.; Flatt, S. W.; Zwart, W.; Linn, S. C.; Parker, B. A.; Wu, A. H. B.; Pierce, J. P.; Huitema, A. D. R.; Beijnen, J. H.

    2018-01-01

    Purpose Endoxifen concentrations have been associated with breast cancer recurrence in tamoxifen-treated patients. However, tamoxifen itself and other metabolites also show antiestrogenic anti-tumor activity. Therefore, the aim of this study was to develop a comprehensive Antiestrogenic Activity Score (AAS), which accounts for concentration and antiestrogenic activity of tamoxifen and three metabolites. An association between the AAS and recurrence-free survival was investigated and compared to a previously published threshold for endoxifen concentrations of 5.97 ng/mL. Patients and methods The antiestrogenic activities of tamoxifen, (Z)-endoxifen, (Z)-4-hydroxytamoxifen, and N-desmethyltamoxifen were determined in a cell proliferation assay. The AAS was determined by calculating the sum of each metabolite concentration multiplied by an IC50 ratio, relative to tamoxifen. The AAS was calculated for 1370 patients with estrogen receptor alpha (ERα)-positive breast cancer. An association between AAS and recurrence was investigated using Cox regression and compared with the 5.97 ng/mL endoxifen threshold using concordance indices. Results An AAS threshold of 1798 was associated with recurrence-free survival, hazard ratio (HR) 0.67 (95% confidence interval (CI) 0.47–0.96), bias corrected after bootstrap HR 0.69 (95% CI 0.48–0.99). The concordance indices for AAS and endoxifen did not significantly differ; however, using the AAS threshold instead of endoxifen led to different dose recommendations for 5.2% of the patients. Conclusions Endoxifen concentrations can serve as a proxy for the antiestrogenic effect of tamoxifen and metabolites. However, for the aggregate effect of tamoxifen and three metabolites, defined by an integrative algorithm, a trend towards improving treatment is seen and moreover, is significantly associated with breast cancer recurrence. PMID:28005246

  12. Development and application of an in-cell cleanup pressurized liquid extraction with ultra-high-performance liquid chromatography-tandem mass spectrometry to detect prohibited antiviral agents sensitively in livestock and poultry feces.

    PubMed

    Wu, Huizhen; Wang, Jianmei; Yang, Hua; Li, Guoqin; Zeng, Yinhuan; Xia, Wei; Li, Zuguang; Qian, Mingrong

    2017-03-10

    An in-cell cleanup pressurized liquid extraction was developed to analyze prohibited antiviral agents in livestock and poultry feces. Extraction and cleanup were integrated into one step. The extraction was performed using methanol-acetonitrile (1:1, v/v) with 0.5% glacial acetic acid at 90°C, and 0.75g of PSA was used as the adsorbent during the extraction procedure. Under optimal conditions, the average recoveries for 11 antiviral drugs were 71.5-112.5% at three spiked levels (20, 40, and 100μgkg -1 ). The detection limits and detection quantitations of the analysis method for the eleven antiviral drugs were 0.6-1.4 and 1.4-4.7μgkg -1 , respectively. Finally, the method was applied to analyze amantadine, oseltamivir and its metabolites oseltamivir acid in duck feces based on an experiment of an oral dose of two antiviral drugs in duck. The amantadine, oseltamivir and oseltamivir acid can be detected in feces within approximately four weeks after amantadine and oseltamivir were orally administered. The results indicate that the residue analysis in feces is a noninvasive method to monitor inhibited antiviral agents efficiently in livestock and poultry breeding. Copyright © 2017. Published by Elsevier B.V.

  13. Linking diet, physical activity, cardiorespiratory fitness and obesity to serum metabolite networks: findings from a population-based study

    PubMed Central

    Floegel, A; Wientzek, A; Bachlechner, U; Jacobs, S; Drogan, D; Prehn, C; Adamski, J; Krumsiek, J; Schulze, M B; Pischon, T; Boeing, H

    2014-01-01

    Objective: It is not yet resolved how lifestyle factors and intermediate phenotypes interrelate with metabolic pathways. We aimed to investigate the associations between diet, physical activity, cardiorespiratory fitness and obesity with serum metabolite networks in a population-based study. Methods: The present study included 2380 participants of a randomly drawn subcohort of the European Prospective Investigation into Cancer and Nutrition-Potsdam. Targeted metabolomics was used to measure 127 serum metabolites. Additional data were available including anthropometric measurements, dietary assessment including intake of whole-grain bread, coffee and cake and cookies by food frequency questionnaire, and objectively measured physical activity energy expenditure and cardiorespiratory fitness in a subsample of 100 participants. In a data-driven approach, Gaussian graphical modeling was used to draw metabolite networks and depict relevant associations between exposures and serum metabolites. In addition, the relationship of different exposure metabolite networks was estimated. Results: In the serum metabolite network, the different metabolite classes could be separated. There was a big group of phospholipids and acylcarnitines, a group of amino acids and C6-sugar. Amino acids were particularly positively associated with cardiorespiratory fitness and physical activity. C6-sugar and acylcarnitines were positively associated with obesity and inversely with intake of whole-grain bread. Phospholipids showed opposite associations with obesity and coffee intake. Metabolite networks of coffee intake and obesity were strongly inversely correlated (body mass index (BMI): r=−0.57 and waist circumference: r=−0.59). A strong positive correlation was observed between metabolite networks of BMI and waist circumference (r=0.99), as well as the metabolite networks of cake and cookie intake with cardiorespiratory fitness and intake of whole-grain bread (r=0.52 and r=0

  14. Linking diet, physical activity, cardiorespiratory fitness and obesity to serum metabolite networks: findings from a population-based study.

    PubMed

    Floegel, A; Wientzek, A; Bachlechner, U; Jacobs, S; Drogan, D; Prehn, C; Adamski, J; Krumsiek, J; Schulze, M B; Pischon, T; Boeing, H

    2014-11-01

    It is not yet resolved how lifestyle factors and intermediate phenotypes interrelate with metabolic pathways. We aimed to investigate the associations between diet, physical activity, cardiorespiratory fitness and obesity with serum metabolite networks in a population-based study. The present study included 2380 participants of a randomly drawn subcohort of the European Prospective Investigation into Cancer and Nutrition-Potsdam. Targeted metabolomics was used to measure 127 serum metabolites. Additional data were available including anthropometric measurements, dietary assessment including intake of whole-grain bread, coffee and cake and cookies by food frequency questionnaire, and objectively measured physical activity energy expenditure and cardiorespiratory fitness in a subsample of 100 participants. In a data-driven approach, Gaussian graphical modeling was used to draw metabolite networks and depict relevant associations between exposures and serum metabolites. In addition, the relationship of different exposure metabolite networks was estimated. In the serum metabolite network, the different metabolite classes could be separated. There was a big group of phospholipids and acylcarnitines, a group of amino acids and C6-sugar. Amino acids were particularly positively associated with cardiorespiratory fitness and physical activity. C6-sugar and acylcarnitines were positively associated with obesity and inversely with intake of whole-grain bread. Phospholipids showed opposite associations with obesity and coffee intake. Metabolite networks of coffee intake and obesity were strongly inversely correlated (body mass index (BMI): r = -0.57 and waist circumference: r = -0.59). A strong positive correlation was observed between metabolite networks of BMI and waist circumference (r = 0.99), as well as the metabolite networks of cake and cookie intake with cardiorespiratory fitness and intake of whole-grain bread (r = 0.52 and r = 0.50; respectively). Lifestyle factors

  15. In-stream attenuation of neuro-active pharmaceuticals and their metabolites

    USGS Publications Warehouse

    Writer, Jeffrey; Antweiler, Ronald C.; Ferrar, Imma; Ryan, Joseph N.; Thurman, Michael

    2013-01-01

    In-stream attenuation was determined for 14 neuro-active pharmaceuticals and associated metabolites. Lagrangian sampling, which follows a parcel of water as it moves downstream, was used to link hydrological and chemical transformation processes. Wastewater loading of neuro-active compounds varied considerably over a span of several hours, and thus a sampling regime was used to verify that the Lagrangian parcel was being sampled and a mechanism was developed to correct measured concentrations if it was not. In-stream attenuation over the 5.4-km evaluated reach could be modeled as pseudo-first-order decay for 11 of the 14 evaluated neuro-active pharmaceutical compounds, illustrating the capacity of streams to reduce conveyance of neuro-active compounds downstream. Fluoxetine and N-desmethyl citalopram were the most rapidly attenuated compounds (t1/2 = 3.6 ± 0.3 h, 4.0 ± 0.2 h, respectively). Lamotrigine, 10,11,-dihydro-10,11,-dihydroxy-carbamazepine, and carbamazepine were the most persistent (t1/2 = 12 ± 2.0 h, 12 ± 2.6 h, 21 ± 4.5 h, respectively). Parent compounds (e.g., buproprion, carbamazepine, lamotrigine) generally were more persistent relative to their metabolites. Several compounds (citalopram, venlafaxine, O-desmethyl-venlafaxine) were not attenuated. It was postulated that the primary mechanism of removal for these compounds was interaction with bed sediments and stream biofilms, based on measured concentrations in stream biofilms and a column experiment using stream sediments.

  16. The metabolism of primaquine to its active metabolite is dependent on CYP 2D6.

    PubMed

    Pybus, Brandon S; Marcsisin, Sean R; Jin, Xiannu; Deye, Gregory; Sousa, Jason C; Li, Qigui; Caridha, Diana; Zeng, Qiang; Reichard, Gregory A; Ockenhouse, Christian; Bennett, Jason; Walker, Larry A; Ohrt, Colin; Melendez, Victor

    2013-06-20

    The efficacy of the 8-aminoquinoline (8AQ) drug primaquine (PQ) has been historically linked to CYP-mediated metabolism. Although to date no clear evidence exists in the literature that unambiguously assigns the metabolic pathway or specific metabolites necessary for activity, recent literature suggests a role for CYP 2D6 in the generation of redox active metabolites. In the present study, the specific CYP 2D6 inhibitor paroxetine was used to assess its effects on the production of specific phenolic metabolites thought to be involved in PQ efficacy. Further, PQ causal prophylactic (developing liver stage) efficacy against Plasmodium berghei in CYP 2D knockout mice was assessed in comparison with a normal C57 background and with humanized CYP 2D6 mice to determine the direct effects of CYP 2D6 metabolism on PQ activity. PQ exhibited no activity at 20 or 40 mg/kg in CYP 2D knockout mice, compared to 5/5 cures in normal mice at 20 mg/kg. The activity against developing liver stages was partially restored in humanized CYP 2D6 mice. These results unambiguously demonstrate that metabolism of PQ by CYP 2D6 is essential for anti-malarial causal prophylaxis efficacy.

  17. Activation and products of the cryptic secondary metabolite biosynthetic gene clusters by rifampin resistance (rpoB) mutations in actinomycetes.

    PubMed

    Tanaka, Yukinori; Kasahara, Ken; Hirose, Yutaka; Murakami, Kiriko; Kugimiya, Rie; Ochi, Kozo

    2013-07-01

    A subset of rifampin resistance (rpoB) mutations result in the overproduction of antibiotics in various actinomycetes, including Streptomyces, Saccharopolyspora, and Amycolatopsis, with H437Y and H437R rpoB mutations effective most frequently. Moreover, the rpoB mutations markedly activate (up to 70-fold at the transcriptional level) the cryptic/silent secondary metabolite biosynthetic gene clusters of these actinomycetes, which are not activated under general stressful conditions, with the exception of treatment with rare earth elements. Analysis of the metabolite profile demonstrated that the rpoB mutants produced many metabolites, which were not detected in the wild-type strains. This approach utilizing rifampin resistance mutations is characterized by its feasibility and potential scalability to high-throughput studies and would be useful to activate and to enhance the yields of metabolites for discovery and biochemical characterization.

  18. The oxygen-centered radicals scavenging activity of sulfasalazine and its metabolites. A direct protection of the bowel.

    PubMed

    Prónai, L; Yukinobu, I; Láng, I; Fehér, J

    1992-01-01

    Oxygen-centered radicals, such as superoxide (O2-) and hydroxyl radicals (.OH) generated by phagocytes have been suggested to be involved in the pathogenesis of chronic inflammations of the bowel, such as Crohn's disease and colitis ulcerosa. Recently, sulfasalazine (SASP) and its metabolites have been reported to exert their effects as a direct scavenger of oxygen-centered radicals in the bowel. To scavenge oxygen-centered radicals in vivo, however, SASP and its metabolites have to react with O2- and/or .OH in vitro very rapidly, furthermore they have to reach an appropriate (possible millimolar) concentration range at the site of inflammation. To test this possibility, we investigated the direct O2- and .OH scavenging activity of SASP and its metabolites using the specific electron paramagnetic resonance/spin trapping method, and we compared the 50% inhibition rates of SASP and its metabolites with their known concentrations in the bowel and in the human plasma. It was found that SASP and its metabolites, such as 5-amino-salicylic acid (5-ASA), and acetyl-5-amino-salicylic acid (AC-5-ASA), but not sulfapyridine (SP) and acetyl-sulfapyridine (Ac-SP) have a direct O2- and .OH scavenging activity in vitro systems. Among the compounds, SASP and 5-ASA can reach a concentration which is appropriate to scavenge oxygen-centered radicals in the bowel but not in the human plasma. It was concluded that the in vivo antiinflammatory effects of SASP and its metabolites are, at least partly, due to the direct oxygen-centered scavenging activity of these drugs.

  19. Integrated circuit-based electrochemical sensor for spatially resolved detection of redox-active metabolites in biofilms.

    PubMed

    Bellin, Daniel L; Sakhtah, Hassan; Rosenstein, Jacob K; Levine, Peter M; Thimot, Jordan; Emmett, Kevin; Dietrich, Lars E P; Shepard, Kenneth L

    2014-01-01

    Despite advances in monitoring spatiotemporal expression patterns of genes and proteins with fluorescent probes, direct detection of metabolites and small molecules remains challenging. A technique for spatially resolved detection of small molecules would benefit the study of redox-active metabolites that are produced by microbial biofilms and can affect their development. Here we present an integrated circuit-based electrochemical sensing platform featuring an array of working electrodes and parallel potentiostat channels. 'Images' over a 3.25 × 0.9 mm(2) area can be captured with a diffusion-limited spatial resolution of 750 μm. We demonstrate that square wave voltammetry can be used to detect, identify and quantify (for concentrations as low as 2.6 μM) four distinct redox-active metabolites called phenazines. We characterize phenazine production in both wild-type and mutant Pseudomonas aeruginosa PA14 colony biofilms, and find correlations with fluorescent reporter imaging of phenazine biosynthetic gene expression.

  20. Integrated circuit-based electrochemical sensor for spatially resolved detection of redox-active metabolites in biofilms

    PubMed Central

    Bellin, Daniel L.; Sakhtah, Hassan; Rosenstein, Jacob K.; Levine, Peter M.; Thimot, Jordan; Emmett, Kevin; Dietrich, Lars E. P.; Shepard, Kenneth L.

    2014-01-01

    Despite advances in monitoring spatiotemporal expression patterns of genes and proteins with fluorescent probes, direct detection of metabolites and small molecules remains challenging. A technique for spatially resolved detection of small molecules would benefit the study of redox-active metabolites produced by microbial biofilms, which can drastically affect colony development. Here we present an integrated circuit-based electrochemical sensing platform featuring an array of working electrodes and parallel potentiostat channels. “Images” over a 3.25 × 0.9 mm area can be captured with a diffusion-limited spatial resolution of 750 μm. We demonstrate that square wave voltammetry can be used to detect, identify, and quantify (for concentrations as low as 2.6 μM) four distinct redox-active metabolites called phenazines. We characterize phenazine production in both wild-type and mutant Pseudomonas aeruginosa PA14 colony biofilms, and find correlations with fluorescent reporter imaging of phenazine biosynthetic gene expression. PMID:24510163

  1. Evaluation of the in vitro activity of levornidazole, its metabolites and comparators against clinical anaerobic bacteria.

    PubMed

    Hu, Jiali; Zhang, Jing; Wu, Shi; Zhu, Demei; Huang, Haihui; Chen, Yuancheng; Yang, Yang; Zhang, Yingyuan

    2014-12-01

    This study evaluated the in vitro anti-anaerobic activity and spectrum of levornidazole, its metabolites and comparators against 375 clinical isolates of anaerobic bacteria, including Gram-negative bacilli (181 strains), Gram-negative cocci (11 strains), Gram-positive bacilli (139 strains) and Gram-positive cocci (44 strains), covering 34 species. Minimum inhibitory concentrations (MICs) of levornidazole, its five metabolites and three comparators against these anaerobic isolates were determined by the agar dilution method. Minimum bactericidal concentrations (MBCs) of levornidazole and metronidazole were measured against 22 strains of Bacteroides fragilis. Levornidazole showed good activity against B. fragilis, other Bacteroides spp., Clostridium difficile, Clostridium perfringens and Peptostreptococcus magnus, evidenced by MIC90 values of 0.5, 1, 0.25, 2 and 1mg/L, respectively. The activity of levornidazole and the comparators was poor for Veillonella spp. Generally, levornidazole displayed activity similar to or slightly higher than that of metronidazole, ornidazole and dextrornidazole against anaerobic Gram-negative bacilli, Gram-positive bacilli and Gram-positive cocci, especially B. fragilis. Favourable anti-anaerobic activity was also seen with levornidazole metabolites M1 and M4 but not M2, M3 or M5. For the 22 clinical B. fragilis strains, MBC50 and MBC90 values of levornidazole were 2mg/L and 4mg/L, respectively. Both MBC50/MIC50 and MBC90/MIC90 ratios of levornidazole were 4, similar to those of metronidazole. Levornidazole is an important anti-anaerobic option in clinical settings in terms of its potent and broad-spectrum in vitro activity, bactericidal property, and the anti-anaerobic activity of its metabolites M1 and M4. Copyright © 2014 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

  2. In Vitro Antibacterial Activities of AF 3013, the Active Metabolite of Prulifloxacin, against Nosocomial and Community Italian Isolates

    PubMed Central

    Montanari, Maria Pia; Mingoia, Marina; Varaldo, Pietro Emanuele

    2001-01-01

    AF 3013, the active metabolite of prulifloxacin, was tested to determine its inhibitory and bactericidal activities against 396 nosocomial and 258 community Italian isolates. Compared with that of ciprofloxacin, its activity (assessed in MIC and minimal bactericidal concentration tests) was generally similar or greater against gram-positive bacteria and greater against gram-negative bacteria. In time-kill assays using selected isolates, its bactericidal activity was comparable to that of ciprofloxacin. PMID:11709353

  3. Effects of clopidogrel on the pharmacokinetics of sibutramine and its active metabolites.

    PubMed

    Bae, Jung-Woo; Jang, Choon-Gon; Lee, Seok-Young

    2011-12-01

    Sibutramine is metabolized by the enzymes CYP2B6 and CYP2C19 into 2 active metabolites, M1 (mono-desmethyl sibutramine) and M2 (di-desmethyl sibutramine). Clopidogrel is a mechanism-based inhibitor of CYP2B6 and CYP2C19. In this study, 13 extensive metabolizers of CYP2B6 and CYP2C19 were evaluated to clarify whether clopidogrel inhibits the formation of the active metabolites of sibutramine. In the control phase, each subject received a 15-mg oral dose of sibutramine. After a washout period of 2 weeks, in the clopidogrel phase, the subjects received 300 mg of clopidogrel on the first day and then 75-mg once daily for 6 days. One hour after the last dosing of clopidogrel, all subjects received 15-mg of sibutramine. Compared with the control phase, the mean sibutramine and M1 plasma concentrations were higher after clopidogrel treatment. Clopidogrel significantly increased the half-life (242% of control phase) and area under the plasma concentration-time curve from 0 to infinity (AUC(inf)) (227% of control phase) of sibutramine and decreased the apparent oral clearance (31% of control phase) of sibutramine. Pharmacokinetic analysis showed significant increases in the AUC(inf) (162% of control phase) of M1. The CYP2B6 and CYP2C19 inhibitor clopidogrel significantly inhibited the formations of M1 from sibutramine and M2 from sibutramine by 37% and 64%, respectively. Therefore, CYP2B6 and CYP2C19 are in vivo catalysts for the formation of the 2 active metabolites of sibutramine.

  4. Bisphenol-A alters microbiota metabolites derived from aromatic amino acids and worsens disease activity during colitis.

    PubMed

    DeLuca, Jennifer Aa; Allred, Kimberly F; Menon, Rani; Riordan, Rebekah; Weeks, Brad R; Jayaraman, Arul; Allred, Clinton D

    2018-06-01

    Inflammatory bowel disease is a complex collection of disorders. Microbial dysbiosis as well as exposure to toxins including xenoestrogens are thought to be risk factors for inflammatory bowel disease development and relapse. Bisphenol-A has been shown to exert estrogenic activity in the colon and alter intestinal function, but the role that xenoestrogens, such as bisphenol-A , play in colonic inflammation has been previously described but with conflicting results. We investigated the ability of bisphenol-A to exacerbate colonic inflammation and alter microbiota metabolites derived from aromatic amino acids in an acute dextran sulfate sodium-induced colitis model. Female C57BL/6 mice were ovariectomized and exposed to bisphenol-A daily for 15 days. Disease activity measures include body weight, fecal consistency, and rectal bleeding. Colons were scored for inflammation, injury, and nodularity. Alterations in the levels of microbiota metabolites derived from aromatic amino acids known to reflect phenotypic changes in the gut microbiome were analyzed. Bisphenol-A exposure increased mortality and worsened disease activity as well as inflammation and nodularity scores in the middle colon region following dextran sulfate sodium exposure. Unique patterns of metabolites were associated with bisphenol-A consumption. Regardless of dextran sulfate sodium treatment, bisphenol-A reduced levels of tryptophan and several metabolites associated with decreased inflammation in the colon. This is the first study to show that bisphenol-A treatment alone can reduce microbiota metabolites derived from aromatic amino acids in the colon which may be associated with increased colonic inflammation and inflammatory bowel disease. Impact statement As rates of inflammatory bowel disease rise, discovery of the mechanisms related to the development of these conditions is important. Environmental exposure is hypothesized to play a role in etiology of the disease, as are alterations in the gut

  5. Metabolites related to renal function, immune activation, and carbamylation are associated with muscle composition in older adults.

    PubMed

    Lustgarten, Michael S; Fielding, Roger A

    2017-12-15

    Reduced skeletal muscle density in older adults is associated with insulin resistance, decreased physical function, and an increased all-cause mortality risk. To elucidate mechanisms that may underlie the maintenance of skeletal muscle density, we conducted a secondary analysis of previously published muscle composition and serum metabolomic data in 73 older adults (average age, 78y). Multivariable-adjusted linear regression was used to examine associations between 321 metabolites with muscle composition, defined as the ratio between normal density (NDM) with low density (LDM) thigh muscle cross sectional area (NDM/LDM). Sixty metabolites were significantly (p≤0.05 and q<0.30) associated with NDM/LDM. Decreased renal function and the immune response have been previously linked with reduced muscle density, but the mechanisms underlying these connections are less clear. Metabolites that were significantly associated with muscle composition were then tested for their association with circulating markers of renal function (blood urea nitrogen, creatinine, uric acid), and with the immune response (neutrophils/lymphocytes) and activation (kynurenine/tryptophan). 43 significant NDM/LDM metabolites (including urea) were co-associated with at least 1 marker of renal function; 23 of these metabolites have been previously identified as uremic solutes. The neutrophil/lymphocyte ratio was significantly associated with NDM/LDM (β±SE: -0.3±0.1, p=0.01, q=0.04). 35 significant NDM/LDM metabolites were co-associated with immune activation. Carbamylation (defined as homocitrulline/lysine) was identified as a pathway that may link renal function and immune activation with muscle composition, as 29 significant NDM/LDM metabolites were co-associated with homocitrulline/lysine, with at least 2 markers of renal function, and with kynurenine/tryptophan. When considering that elevated urea and uremic metabolites have been linked with an increased systemic microbial burden, that

  6. Secondary Metabolites Produced by an Endophytic Fungus Pestalotiopsis sydowiana and Their 20S Proteasome Inhibitory Activities.

    PubMed

    Xia, Xuekui; Kim, Soonok; Liu, Changheng; Shim, Sang Hee

    2016-07-20

    Fungal endophytes have attracted attention due to their functional diversity. Secondary metabolites produced by Pestalotiopsis sydowiana from a halophyte, Phragmites communis Trinus, were investigated. Eleven compounds, including four penicillide derivatives (1-4) and seven α-pyrone analogues (5-10) were isolated from cultures of P. sydowiana. The compounds were identified based on spectroscopic data. The inhibitory activities against the 20S proteasome were evaluated. Compounds 1-3, 5, and 9-10 showed modest proteasome inhibition activities, while compound 8 showed strong activity with an IC50 of 1.2 ± 0.3 μM. This is the first study on the secondary metabolites produced by P. sydowiana and their proteasome inhibitory activities. The endophytic fungus P. sydowiana might be a good resource for proteasome inhibitors.

  7. Activation of the Silent Secondary Metabolite Production by Introducing Neomycin-Resistance in a Marine-Derived Penicillium purpurogenum G59

    PubMed Central

    Wu, Chang-Jing; Yi, Le; Cui, Cheng-Bin; Li, Chang-Wei; Wang, Nan; Han, Xiao

    2015-01-01

    Introduction of neomycin-resistance into a marine-derived, wild-type Penicillium purpurogenum G59 resulted in activation of silent biosynthetic pathways for the secondary metabolite production. Upon treatment of G59 spores with neomycin and dimethyl sulfoxide (DMSO), a total of 56 mutants were obtained by single colony isolation. The acquired resistance of mutants to neomycin was testified by the resistance test. In contrast to the G59 strain, the EtOAc extracts of 28 mutants inhibited the human cancer K562 cells, indicating that the 28 mutants have acquired the capability to produce bioactive metabolites. HPLC-photodiode array detector (PDAD)-UV and HPLC-electron spray ionization (ESI)-MS analyses further indicated that diverse secondary metabolites have been newly produced in the bioactive mutant extracts. Followed isolation and characterization demonstrated that five bioactive secondary metabolites, curvularin (1), citrinin (2), penicitrinone A (3), erythro-23-O-methylneocyclocitrinol (4) and 22E-7α-methoxy-5α,6α-epoxyergosta-8(14),22-dien-3β-ol (5), were newly produced by a mutant, 4-30, compared to the G59 strain. All 1–5 were also not yet found in the secondary metabolites of other wild type P. purpurogenum strains. Compounds 1–5 inhibited human cancer K562, HL-60, HeLa and BGC-823 cells to varying extents. Both present bioassays and chemical investigations demonstrated that the introduction of neomycin-resistance into the marine-derived fungal G59 strain could activate silent secondary metabolite production. The present work not only extended the previous DMSO-mediated method for introducing drug-resistance in fungi both in DMSO concentrations and antibiotics, but also additionally exemplified effectiveness of this method for activating silent fungal secondary metabolites. This method could be applied to other fungal isolates to elicit their metabolic potentials to investigate secondary metabolites from silent biosynthetic pathways. PMID:25913704

  8. Activation of the silent secondary metabolite production by introducing neomycin-resistance in a marine-derived Penicillium purpurogenum G59.

    PubMed

    Wu, Chang-Jing; Yi, Le; Cui, Cheng-Bin; Li, Chang-Wei; Wang, Nan; Han, Xiao

    2015-04-22

    Introduction of neomycin-resistance into a marine-derived, wild-type Penicillium purpurogenum G59 resulted in activation of silent biosynthetic pathways for the secondary metabolite production. Upon treatment of G59 spores with neomycin and dimethyl sulfoxide (DMSO), a total of 56 mutants were obtained by single colony isolation. The acquired resistance of mutants to neomycin was testified by the resistance test. In contrast to the G59 strain, the EtOAc extracts of 28 mutants inhibited the human cancer K562 cells, indicating that the 28 mutants have acquired the capability to produce bioactive metabolites. HPLC-photodiode array detector (PDAD)-UV and HPLC-electron spray ionization (ESI)-MS analyses further indicated that diverse secondary metabolites have been newly produced in the bioactive mutant extracts. Followed isolation and characterization demonstrated that five bioactive secondary metabolites, curvularin (1), citrinin (2), penicitrinone A (3), erythro-23-O-methylneocyclocitrinol (4) and 22E-7α-methoxy-5α, 6α-epoxyergosta-8(14),22-dien-3β-ol (5), were newly produced by a mutant, 4-30, compared to the G59 strain. All 1-5 were also not yet found in the secondary metabolites of other wild type P. purpurogenum strains. Compounds 1-5 inhibited human cancer K562, HL-60, HeLa and BGC-823 cells to varying extents. Both present bioassays and chemical investigations demonstrated that the introduction of neomycin-resistance into the marine-derived fungal G59 strain could activate silent secondary metabolite production. The present work not only extended the previous DMSO-mediated method for introducing drug-resistance in fungi both in DMSO concentrations and antibiotics, but also additionally exemplified effectiveness of this method for activating silent fungal secondary metabolites. This method could be applied to other fungal isolates to elicit their metabolic potentials to investigate secondary metabolites from silent biosynthetic pathways.

  9. Impact of limited solvent capacity on metabolic rate, enzyme activities, and metabolite concentrations of S. cerevisiae glycolysis.

    PubMed

    Vazquez, Alexei; de Menezes, Marcio A; Barabási, Albert-László; Oltvai, Zoltan N

    2008-10-01

    The cell's cytoplasm is crowded by its various molecular components, resulting in a limited solvent capacity for the allocation of new proteins, thus constraining various cellular processes such as metabolism. Here we study the impact of the limited solvent capacity constraint on the metabolic rate, enzyme activities, and metabolite concentrations using a computational model of Saccharomyces cerevisiae glycolysis as a case study. We show that given the limited solvent capacity constraint, the optimal enzyme activities and the metabolite concentrations necessary to achieve a maximum rate of glycolysis are in agreement with their experimentally measured values. Furthermore, the predicted maximum glycolytic rate determined by the solvent capacity constraint is close to that measured in vivo. These results indicate that the limited solvent capacity is a relevant constraint acting on S. cerevisiae at physiological growth conditions, and that a full kinetic model together with the limited solvent capacity constraint can be used to predict both metabolite concentrations and enzyme activities in vivo.

  10. Impact of Limited Solvent Capacity on Metabolic Rate, Enzyme Activities, and Metabolite Concentrations of S. cerevisiae Glycolysis

    PubMed Central

    Vazquez, Alexei; de Menezes, Marcio A.; Barabási, Albert-László; Oltvai, Zoltan N.

    2008-01-01

    The cell's cytoplasm is crowded by its various molecular components, resulting in a limited solvent capacity for the allocation of new proteins, thus constraining various cellular processes such as metabolism. Here we study the impact of the limited solvent capacity constraint on the metabolic rate, enzyme activities, and metabolite concentrations using a computational model of Saccharomyces cerevisiae glycolysis as a case study. We show that given the limited solvent capacity constraint, the optimal enzyme activities and the metabolite concentrations necessary to achieve a maximum rate of glycolysis are in agreement with their experimentally measured values. Furthermore, the predicted maximum glycolytic rate determined by the solvent capacity constraint is close to that measured in vivo. These results indicate that the limited solvent capacity is a relevant constraint acting on S. cerevisiae at physiological growth conditions, and that a full kinetic model together with the limited solvent capacity constraint can be used to predict both metabolite concentrations and enzyme activities in vivo. PMID:18846199

  11. Major secondary metabolites produced by two commercial Trichoderma strains active against different phytopathogens.

    PubMed

    Vinale, F; Marra, R; Scala, F; Ghisalberti, E L; Lorito, M; Sivasithamparam, K

    2006-08-01

    Trichoderma harzianum strains T22 and T39 are two micro-organisms used as active agents in a variety of commercial biopesticides and biofertilizers and widely applied amongst field and greenhouse crops. The production, isolation, biological and chemical characterization of the main secondary metabolites produced by these strains are investigated. Of the three major compounds produced by strain T22, one is a new azaphilone that shows marked in vitro inhibition of Rhizoctonia solani, Pythium ultimum and Gaeumannomyces graminis var. tritici. In turn, filtrates from strain T39 were demonstrated to contain two compounds previously isolated from other T. harzianum strains and a new butenolide. The production of the isolated metabolites was also monitored by liquid chromatography/mass spectrometry during in vitro interaction with R. solani. This paper reports the isolation and characterization of the main secondary metabolites obtained from culture filtrates of two T. harzianum strains and their production during antagonistic interaction with the pathogen R. solani. This is the first work on secondary metabolites produced by the commercially applied strains T22 and T39. Our results provide a better understanding of the metabolism of these fungi, which are both widely used as biopesticides and/or biofertilizers in biocontrol.

  12. The urinary metabolites of DINCH® have an impact on the activities of the human nuclear receptors ERα, ERβ, AR, PPARα and PPARγ.

    PubMed

    Engel, Anika; Buhrke, Thorsten; Kasper, Stefanie; Behr, Anne-Cathrin; Braeuning, Albert; Jessel, Sönke; Seidel, Albrecht; Völkel, Wolfgang; Lampen, Alfonso

    2018-05-01

    DINCH ® (di-isononyl cyclohexane-1,2-dicarboxylate) is a non-phthalate plasticizer that has been developed to replace phthalate plasticizers such as DEHP (di-2-ethylhexyl phthalate) or DINP (di-isononyl phthalate). DINCH ® is metabolized to its corresponding monoester and subsequently to oxidized monoester derivatives. These are conjugated to glucuronic acid and subject to urinary excretion. In contrast to DINCH ® , there are almost no toxicological data available regarding its primary and secondary metabolites. The present study aimed at the characterization of potential endocrine properties of DINCH ® and five DINCH ® metabolites by using reporter gene assays to monitor the activity of the human nuclear receptors ERα, ERβ, AR, PPARα and PPARγ in vitro. DINCH ® itself did not have any effect on the activity of these receptors whereas DINCH ® metabolites were shown to activate all these receptors. In the case of AR, DINCH ® metabolites predominantly enhanced dihydrotestosterone-stimulated AR activity. In the H295R steroidogenesis assay, neither DINCH ® nor any of its metabolites affected estradiol or testosterone synthesis. In conclusion, primary and secondary DINCH ® metabolites exert different effects at the molecular level compared to DINCH ® itself. All these in vitro effects of DINCH ® metabolites, however, were only observed at high concentrations such as 10 μM or above which is about three orders of magnitude above reported DINCH ® metabolite concentrations in human urine. Thus, the in vitro data do not support the notion that DINCH ® or any of the investigated metabolites may exert considerable endocrine effects in vivo at relevant human exposure levels. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. Mutagenic activity of austocystins - secondary metabolites of Aspergillus ustus

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

    Kfir, R.; Johannsen, E.; Vleggaar, R.

    1986-11-01

    Mycotoxins constitute a group of toxic secondary fungal metabolites. Fungi that produce these toxins frequently contaminate food and feed, creating a potential threat to human and animal health. Biological activities of mycotoxins include, amongst others: toxicity, mutagenicity and carcinogenicity, which can be expressed with or without metabolic activation. Austocystins are similar in structure to aflatoxin B/sup 1/ and are probably synthesized in a similar manner. The Ames Salmonella test, a widely accepted method employed for the detection of mutagenic activity of various chemical compounds was used for testing the mutagenic activity of different mycotoxins. As aflatoxin B/sup 1/ was foundmore » by the Ames test to be highly mutagenic, the same test was applied for the study of possible mutagenicity of the austocystins. The mutagenic activity of these compounds was studied with and without metabolic activation using two tester strains of S. typhimurium, one capable of detecting frame shift mutation (strain TA98) and the other capable of detecting base pair substitution (strain TA100).« less

  14. [The pharmacokinetics of the dipeptide analog of piracetam with nootropic activity GVS-111 and of its basic metabolites].

    PubMed

    Boĭko, S S; Zherdev, V P; Dvorianinov, A A; Gudasheva, T A; Ostrovskaia, R U; Voronina, T A; Rozantsev, G G; Seredenin, S B

    1997-01-01

    The pharmacokinetics of a new nootropic dipeptide analog of piracetam-N-phenylacetyl-L-prolylglycine (GWS-111) and its main metabolites were studied in rats by means of high performance liquid chromatography and gas-liquid chromatography. The compound under study showed a greater resistance to an enzymatic effect than natural neuropeptides. In addition to an unchanged compound three of its metabolites were found in the blood plasma of the rats. One of them, cyclo-Pro-Gly was an active metabolite of GWS-111.

  15. Porritoxins, metabolites of Alternaria porri, as anti-tumor-promoting active compounds.

    PubMed

    Horiuchi, Masayuki; Tokuda, Harukuni; Ohnishi, Keiichiro; Yamashita, Masakazu; Nishino, Hoyoku; Maoka, Takashi

    2006-02-01

    To search for possible cancer chemopreventive agents from natural sources, we performed primary screening of metabolites of Alternaria porri by examining their possible inhibitory effects on Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells. The ethyl acetate extract of A. porri showed the inhibitory effect on EBV-EA activation. Three porritoxins (1-3) were obtained as inhibitory active compounds for EBV-EA from ethyl acetate extract. 6-(3',3'-Dimethylallyloxy)-4-methoxy-5-methylphthalide (2) showed the strongest activity among them. Inhibitory effect of porritoxin (1) and (2) was superior to that of beta-carotene, a well-known anti-tumor promoter. Furthermore, the structure-activity correlation of porritoxins and their related compounds were discussed.

  16. Microbial transformation of (+)-nootkatone and the antiproliferative activity of its metabolites.

    PubMed

    Gliszczyńska, Anna; Łysek, Agnieszka; Janeczko, Tomasz; Świtalska, Marta; Wietrzyk, Joanna; Wawrzeńczyk, Czesław

    2011-04-01

    Six metabolites were obtained as a result of microbial transformation of (+)-nootkatone (1) by the fungal strains: Botrytis, Didymosphaeria, Aspergillus, Chaetomium and Fusarium. Their structure were established as (+)-(4R,5S,7R,9R)-9α-hydroxynootkatone (2), (+)-(4R,5S,7R)-13-hydroxynootkatone (3) and (+)-(4R,5S,7R,9R,11S)-11,12-epoxy-9α-hydroxynootkatone (4), (+)-(4R,5S,7R,11S)-11,12-epoksynootkatone (5), (+)-(4R,5S,7R)-11,12-dihydroxynootkatone (6) and (+)-(4R,5S,7R)-7,11,12-trihydroxynootkatone (7) on the basis of their spectral data. Two products: (4) and (7) were not previously reported in the literature. The antiproliferative activity of (+)-nootkatone (1) and isolated metabolites (2-7) of its biotransformation has been evaluated. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Passage of irinotecan and its active metabolite, SN-38, into human milk.

    PubMed

    Nakagawa, J; Terui, K; Hosoi, K; Ueno, K; Yokoyama, Y; Hayakari, M

    2016-10-01

    We measured the levels of irinotecan and its active metabolite, SN-38, in human milk after the administration of irinotecan to assess the potential risks when women treated with irinotecan nurse their infants. Human milk was collected for 6 days starting on the day after irinotecan was administered. The levels of irinotecan and SN-38 in human milk were measured using liquid chromatography-mass spectrometry. Irinotecan was detected on Days 2 and 3 but not after Day 4. A strong signal indicating the presence of SN-38 was detected on Day 2 and the signal was readily detected until Day 7, indicating that SN-38 remained in human milk. Intravenously administered CPT-11 continues to pass into human milk over a prolonged period in the form of its active metabolite, SN-38. The relationship between administration of CPT-11 and SN-38 exposure and toxicity is still not well defined, so patients should avoid nursing their infants while they are being treated with CPT-11. © 2016 John Wiley & Sons Ltd.

  18. Regulatory requirements for genotoxicity assessment of plant protection product active ingredients, impurities, and metabolites.

    PubMed

    Booth, Ewan D; Rawlinson, Paul J; Maria Fagundes, Priscila; Leiner, Kevin A

    2017-06-01

    Active ingredients in plant protection products are subject to rigorous safety assessment during their development, including assessment of genotoxicity. Plant protection products are used for agriculture in multiple regions and for the registration of active ingredients it is necessary to satisfy the data requirements of these different regions. There are no overarching global agreements on which genotoxicity studies need to be conducted to satisfy the majority of regulatory authorities. The implementation of new OECD guidelines for the in vitro micronucleus, transgenic rodent somatic and germ cell gene mutation and in vivo comet assays, as well as the revision of a number of other OECD test guidelines has resulted in some changes to data requirements. This review describes the genotoxicity data requirements for chemical active ingredients as well as biologicals, microbials, ground water metabolites, metabolites, and impurities in a number of regions. Similarities and differences are highlighted. Environ. Mol. Mutagen. 58:325-344, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  19. Application of electrolysis for inactivation of an antiviral drug that is one of possible selection pressure to drug-resistant influenza viruses.

    PubMed

    Kobayashi, Toyohide; Hirose, Jun; Wu, Hong; Sano, Kouichi; Katsumata, Takahiro; Tsujibo, Hiroshi; Nakano, Takashi

    2013-12-01

    The recent development of antiviral drugs has led to concern that the release of the chemicals in surface water due to expanded medical use could induce drug-resistant mutant viruses in zoonosis. Many researchers have noted that the appearance of an oseltamivir (Tamiflu(®))-resistant avian influenza mutant virus, which may spread to humans, could be induced by oseltamivir contamination of surface water. Although past studies have reported electrolysis as a possible method for degradation of antineoplastics and antibacterials in water, the validity of the method for treatment of antiviral drugs is unknown. In this study, electrolysis was used to degrade an antiviral prodrug, oseltamivir, and a stable active form, oseltamivir carboxylate, and the degradation process was monitored with HPLC-UV and the neuraminidase inhibitory assay. HPLC-UV-detectable oseltamivir and oseltamivir carboxylate were decomposed by electrolysis within 60 min, and inhibitory activity of neuraminidase decreased below the detection limit of the assay used. Cytotoxic and genotoxic activity were not detected in electrolyzed fluid. These results indicate that electrolysis is a possible treatment for inactivation of the antiviral drug oseltamivir. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. Differential effects of clinically used derivatives and metabolites of artemisinin in the activation of constitutive androstane receptor isoforms

    PubMed Central

    Burk, O; Piedade, R; Ghebreghiorghis, L; Fait, JT; Nussler, AK; Gil, JP; Windshügel, B; Schwab, M

    2012-01-01

    BACKGROUND AND PURPOSE Widespread resistance to antimalarial drugs requires combination therapies with increasing risk of pharmacokinetic drug–drug interactions. Here, we explore the capacity of antimalarial drugs to induce drug metabolism via activation of constitutive androstane receptors (CAR) by ligand binding. EXPERIMENTAL APPROACH A total of 21 selected antimalarials and 11 major metabolites were screened for binding to CAR isoforms using cellular and in vitro CAR-coactivator interaction assays, combined with in silico molecular docking. Identified ligands were further characterized by cell-based assays and primary human hepatocytes were used to elucidate induction of gene expression. KEY RESULTS Only two artemisinin derivatives arteether and artemether, the metabolite deoxyartemisinin and artemisinin itself demonstrated agonist binding to the major isoforms CAR1 and CAR3, while arteether and artemether were also inverse agonists of CAR2. Dihydroartemisinin and artesunate acted as weak inverse agonists of CAR1. While arteether showed the highest activities in vitro, it was less active than artemisinin in inducing hepatic CYP3A4 gene expression in hepatocytes. CONCLUSIONS AND IMPLICATIONS Artemisinin derivatives and metabolites differentially affect the activities of CAR isoforms and of the pregnane X receptor (PXR). This negates a common effect of these drugs on CAR/PXR-dependent induction of drug metabolism and further provides an explanation for artemisinin consistently inducing cytochrome P450 genes in vivo, whereas arteether and artemether do not. All these drugs are metabolized very rapidly, but only artemisinin is converted to an enzyme-inducing metabolite. For better understanding of pharmacokinetic drug–drug interaction possibilities, the inducing properties of artemisinin metabolites should be considered. PMID:22577882

  1. Comparison of pharmacokinetics of loxoprofen and its active metabolites after an intravenous, intramuscular, and oral administration of loxoprofen in rats: evidence for extrahepatic metabolism.

    PubMed

    Koo, Tae-Sung; Kim, Dae-Hyun; Ahn, Sung-Hoon; Kim, Kang-Pil; Kim, In-Wha; Seo, Seung-Yong; Suh, Young-Ger; Kim, Dae-Duk; Shim, Chang-Koo; Chung, Suk-Jae

    2005-10-01

    The objective of this study was to characterize the extent of the formation of the active (trans-alcohol form) and inactive (cis-alcohol) metabolites of loxoprofen and to compare the kinetics after its intragastric, intravenous, and intramuscular administrations in rats. After intravenous administration of the drug at doses of 5-20 mg/kg, the clearance and the volume of distribution for loxoprofen, and the ratios of the AUC for the metabolites to the parent drug were not statistically different with the dosage; the formation clearances were 1.08 and 0.87 mL/min/kg for the active and its isomeric metabolite, respectively. After the intragastric, intravenous, or intramuscular administration, AUC for loxoprofen and the metabolites at a dose of 10 mg/kg were not statistically different for the different routes of administration. The formation of the metabolites with the concomitant loss of loxoprofen was found in incubations with liver homogenates and blood but not with a muscle homogenate or plasma, indicating that the conversion of loxoprofen to the metabolites may occur both in the liver and extraheptic tissue(s). Thus, approximately 22% of the loxoprofen may have been converted to the active metabolite in the liver and the extraheptic tissue(s) and the pharmacokinetics of the active metabolite was independent of the route of administration. Copyright (c) 2005 Wiley-Liss, Inc. and the American Pharmacists Association

  2. In vitro antimycoplasmal activities of rufloxacin and its metabolite MF 922.

    PubMed Central

    Furneri, P M; Bisignano, G; Cerniglia, G; Nicoletti, G; Cesana, M; Tempera, G

    1994-01-01

    The in vitro activities of rufloxacin and its metabolite, MF 922, were compared with those of ofloxacin, ciprofloxacin, erythromycin, and minocycline against Mycoplasma pneumoniae, Mycoplasma hominis, Mycoplasma fermentans, and Ureaplasma urealyticum. Rufloxacin, MF 922, and ciprofloxacin shared similar activities against all mycoplasmas tested. (MICs for 90% of isolates tested [MIC90s], 0.5 to 4 micrograms/ml. Ofloxacin had the lowest MIC90s for U. urealyticum, M. fermentans, and M. hominis (MIC90s, 0.25 to 1 micrograms/ml) and erythromycin had the lowest MIC90 for M. pneumoniae (MIC90, 0.004 micrograms/ml). PMID:7872762

  3. Stereoselective synthesis of an active metabolite of the potent PI3 kinase inhibitor PKI-179.

    PubMed

    Chen, Zecheng; Venkatesan, Aranapakam M; Dos Santos, Osvaldo; Delos Santos, Efren; Dehnhardt, Christoph M; Ayral-Kaloustian, Semiramis; Ashcroft, Joseph; McDonald, Leonard A; Mansour, Tarek S

    2010-03-05

    The synthesis and stereochemical determination of 1-(4-(4-((1R,5R,6R)-6-hydroxy-3-oxa-8-azabicyclo[3.2.1]octan-8-yl)-6-morpholino-1,3,5-triazin-2-yl)phenyl)-3-(pyridin-4-yl)urea (2), an active metabolite of the potent PI3 kinase inhibitor PKI-179 (1), is described. Stereospecific hydroboration of the double bond of 2,5-dihydro-1H-pyrrole 8 gave the 2,3-trans alcohol 9 exclusively. The configuration of the 3-hydroxyl group in 9 was inverted by an oxidation and stereoselective reduction sequence to give the corresponding 2,3-cis isomer 23. Both exo (21) and endo (27) isomers of the metabolite 2 were prepared via a practical synthetic route from 9 and 23, respectively, and the stereochemistry of 2 was determined to be endo. The endo isomer (27) was separated into two enantiomers 28 and 29 by chiral HPLC. Compound 2 was found to be enantiomerically pure and identical to the enantiomer 28. The absolute stereochemistry of the enantiomer 28 was determined by Mosher's method, thus establishing the stereochemistry of the active metabolite 2.

  4. The Effect of Oseltamivir on the Disease Progression of Lethal Influenza A Virus Infection: Plasma Cytokine and miRNA Responses in a Mouse Model

    PubMed Central

    Chockalingam, Ashok K.; Hamed, Salaheldin; Goodwin, David G.; Rosenzweig, Barry A.; Pang, Eric; Boyne II, Michael T.

    2016-01-01

    Lethal influenza A virus infection leads to acute lung injury and possibly lethal complications. There has been a continuous effort to identify the possible predictors of disease severity. Unlike earlier studies, where biomarkers were analyzed on certain time points or days after infection, in this study biomarkers were evaluated over the entire course of infection. Circulating proinflammatory cytokines and/or miRNAs that track with the onset and progression of lethal A/Puerto Rico/8/34 (PR8) influenza A virus infection and their response to oseltamivir treatment were investigated up to 10 days after infection. Changes in plasma cytokines (IL-1β, IL-10, IL-12p70, IL-6, KC, TNF-α, and IFN-γ) and several candidate miRNAs were profiled. Among the cytokines analyzed, IL-6 and KC/GRO cytokines appeared to correlate with peak viral titer. Over the selected 48 miRNAs profiled, certain miRNAs were up- or downregulated in a manner that was dependent on the oseltamivir treatment and disease severity. Our findings suggest that IL-6 and KC/GRO cytokines can be a potential disease severity biomarker and/or marker for the progression/remission of infection. Further studies to explore other cytokines, miRNAs, and lung injury proteins in serum with different subtypes of influenza A viruses with varying disease severity may provide new insight into other unique biomarkers. PMID:27110056

  5. Fungal secondary metabolites - strategies to activate silent gene clusters.

    PubMed

    Brakhage, Axel A; Schroeckh, Volker

    2011-01-01

    Filamentous fungi produce a multitude of low molecular weight bioactive compounds. The increasing number of fungal genome sequences impressively demonstrated that their biosynthetic potential is far from being exploited. In fungi, the genes required for the biosynthesis of a secondary metabolite are clustered. Many of these bioinformatically newly discovered secondary metabolism gene clusters are silent under standard laboratory conditions. Consequently, no product can be found. This review summarizes the current strategies that have been successfully applied during the last years to activate these silent gene clusters in filamentous fungi, especially in the genus Aspergillus. The techniques take advantage of genome mining, vary from the simple search for compounds with bioinformatically predicted physicochemical properties up to methods that exploit a probable interaction of microorganisms. Until now, the majority of successful approaches have been based on molecular biology like the generation of gene "knock outs", promoter exchange, overexpression of transcription factors or other pleiotropic regulators. Moreover, strategies based on epigenetics opened a new avenue for the elucidation of the regulation of secondary metabolite formation and will certainly continue to play a significant role for the elucidation of cryptic natural products. The conditions under which a given gene cluster is naturally expressed are largely unknown. One technique is to attempt to simulate the natural habitat by co-cultivation of microorganisms from the same ecosystem. This has already led to the activation of silent gene clusters and the identification of novel compounds in Aspergillus nidulans. These simulation strategies will help discover new natural products in the future, and may also provide fundamental new insights into microbial communication. Copyright © 2010 Elsevier Inc. All rights reserved.

  6. Salicylic acid metabolites and derivatives inhibit CDK activity: Novel insights into aspirin's chemopreventive effects against colorectal cancer

    PubMed Central

    Dachineni, Rakesh; Kumar, D. Ramesh; Callegari, Eduardo; Kesharwani, Siddharth S.; Sankaranarayanan, Ranjini; Seefeldt, Teresa; Tummala, Hemachand; Bhat, G. Jayarama

    2017-01-01

    Aspirin's potential as a drug continues to be evaluated for the prevention of colorectal cancer (CRC). Although multiple targets for aspirin and its metabolite, salicylic acid, have been identified, no unifying mechanism has been proposed to clearly explain its chemopreventive effects. Our goal here was to investigate the ability of salicylic acid metabolites, known to be generated through cytochrome P450 (CYP450) enzymes, and its derivatives as cyclin dependent kinase (CDK) inhibitors to gain new insights into aspirin's chemopreventive actions. Using in vitro kinase assays, for the first time, we demonstrate that salicylic acid metabolites, 2,3-dihydroxy-benzoic acid (2,3-DHBA) and 2,5-dihydroxybenzoic acid (2,5-DHBA), as well as derivatives 2,4-dihydroxybenzoic acid (2,4-DHBA), 2,6-dihydroxybenzoic acid (2,6-DHBA), inhibited CDK1 enzyme activity. 2,3-DHBA and 2,6-DHBA did not inhibit CDK2 and 4; however, both inhibited CDK-6 activity. Interestingly, another derivative, 2,4,6-trihydroxybenzoic acid (2,4,6-THBA) was highly effective in inhibiting CDK1, 2, 4 and 6 activity. Molecular docking studies showed that these compounds potentially interact with CDK1. Immunoblotting experiments showed that aspirin acetylated CDK1, and pre-incubation with salicylic acid and its derivatives prevented aspirin-mediated CDK1 acetylation, which supported the data obtained from molecular docking studies. We suggest that intracellularly generated salicylic acid metabolites through CYP450 enzymes within the colonic epithelial cells, or the salicylic acid metabolites generated by gut microflora may significantly contribute to the preferential chemopreventive effect of aspirin against CRC through inhibition of CDKs. This novel hypothesis and mechanism of action in aspirin's chemopreventive effects opens a new area for future research. In addition, structural modification to salicylic acid derivatives may prove useful in the development of novel CDK inhibitors in cancer prevention and

  7. Solid-Phase Extraction of Sulfur Mustard Metabolites Using an Activated Carbon Fiber Sorbent.

    PubMed

    Lee, Jin Young; Lee, Yong Han

    2016-01-01

    A novel solid-phase extraction method using activated carbon fiber (ACF) was developed and validated. ACF has a vast network of pores of varying sizes and microporous structures that result in rapid adsorption and selective extraction of sulfur mustard metabolites according to the pH of eluting solvents. ACF could not only selectively extract thiodiglycol and 1-methylsulfinyl-2-[2-(methylthio)-ethylsulfonyl]ethane eluting a 9:1 ratio of dichloromethane to acetone, and 1,1'-sulfonylbis[2-(methylsulfinyl)ethane] and 1,1'-sulfonylbis- [2-S-(N-acetylcysteinyl)ethane] eluting 3% hydrogen chloride in methanol, but could also eliminate most interference without loss of analytes during the loading and washing steps. A sample preparation method has been optimized for the extraction of sulfur mustard metabolites from human urine using an ACF sorbent. The newly developed extraction method was applied to the trace analysis of metabolites of sulfur mustard in human urine matrices in a confidence-building exercise for the analysis of biomedical samples provided by the Organisation for the Prohibition of Chemical Weapons. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  8. Activation of the dormant secondary metabolite production by introducing gentamicin-resistance in a marine-derived Penicillium purpurogenum G59.

    PubMed

    Chai, Yun-Jing; Cui, Cheng-Bin; Li, Chang-Wei; Wu, Chang-Jing; Tian, Cong-Kui; Hua, Wei

    2012-03-01

    A new approach to activate silent gene clusters for dormant secondary metabolite production has been developed by introducing gentamicin-resistance to an originally inactive, marine-derived fungal strain Penicillium purpurogenum G59. Upon treatment of the G59 spores with a high concentration of gentamicin in aqueous DMSO, a total of 181 mutants were obtained by single colony isolation. In contrast to the strain G59, the EtOAc extracts of nine mutant cultures showed inhibitory effects on K562 cells, indicating that the nine mutants had acquired capability to produce antitumor metabolites. This was evidenced by TLC and HPLC analysis of EtOAc extracts of G59 and the nine mutants. Further isolation and characterization demonstrated that four antitumor secondary metabolites, janthinone (1), fructigenine A (2), aspterric acid methyl ester (3) and citrinin (4), were newly produced by mutant 5-1-4 compared to the parent strain G59, and which were also not found in the secondary metabolites of other Penicillium purpurogenum strains. However, Compounds 1-4 inhibited the proliferation of K562 cells with inhibition rates of 34.6% (1), 60.8% (2), 31.7% (3) and 67.1% (4) at 100 μg/mL, respectively. The present study demonstrated the effectiveness of a simple, yet practical approach to activate the production of dormant fungal secondary metabolites by introducing acquired resistance to aminoglycoside antibiotics, which could be applied to the studies for eliciting dormant metabolic potential of fungi to obtain cryptic secondary metabolites.

  9. Secondary metabolites from Ganoderma.

    PubMed

    Baby, Sabulal; Johnson, Anil John; Govindan, Balaji

    2015-06-01

    Ganoderma is a genus of medicinal mushrooms. This review deals with secondary metabolites isolated from Ganoderma and their biological significance. Phytochemical studies over the last 40years led to the isolation of 431 secondary metabolites from various Ganoderma species. The major secondary compounds isolated are (a) C30 lanostanes (ganoderic acids), (b) C30 lanostanes (aldehydes, alcohols, esters, glycosides, lactones, ketones), (c) C27 lanostanes (lucidenic acids), (d) C27 lanostanes (alcohols, lactones, esters), (e) C24, C25 lanostanes (f) C30 pentacyclic triterpenes, (g) meroterpenoids, (h) farnesyl hydroquinones (meroterpenoids), (i) C15 sesquiterpenoids, (j) steroids, (k) alkaloids, (l) prenyl hydroquinone (m) benzofurans, (n) benzopyran-4-one derivatives and (o) benzenoid derivatives. Ganoderma lucidum is the species extensively studied for its secondary metabolites and biological activities. Ganoderma applanatum, Ganoderma colossum, Ganoderma sinense, Ganoderma cochlear, Ganoderma tsugae, Ganoderma amboinense, Ganoderma orbiforme, Ganoderma resinaceum, Ganoderma hainanense, Ganoderma concinna, Ganoderma pfeifferi, Ganoderma neo-japonicum, Ganoderma tropicum, Ganoderma australe, Ganoderma carnosum, Ganoderma fornicatum, Ganoderma lipsiense (synonym G. applanatum), Ganoderma mastoporum, Ganoderma theaecolum, Ganoderma boninense, Ganoderma capense and Ganoderma annulare are the other Ganoderma species subjected to phytochemical studies. Further phytochemical studies on Ganoderma could lead to the discovery of hitherto unknown biologically active secondary metabolites. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. 3D-QSAR Studies on a Series of Dihydroorotate Dehydrogenase Inhibitors: Analogues of the Active Metabolite of Leflunomide

    PubMed Central

    Li, Shun-Lai; He, Mao-Yu; Du, Hong-Guang

    2011-01-01

    The active metabolite of the novel immunosuppressive agent leflunomide has been shown to inhibit the enzyme dihydroorotate dehydrogenase (DHODH). This enzyme catalyzes the fourth step in de novo pyrimidine biosynthesis. Self-organizing molecular field analysis (SOMFA), a simple three-dimensional quantitative structure-activity relationship (3D-QSAR) method is used to study the correlation between the molecular properties and the biological activities of a series of analogues of the active metabolite. The statistical results, cross-validated rCV2 (0.664) and non cross-validated r2 (0.687), show a good predictive ability. The final SOMFA model provides a better understanding of DHODH inhibitor-enzyme interactions, and may be useful for further modification and improvement of inhibitors of this important enzyme. PMID:21686163

  11. Oseltamivir phosphate released from injectable Pickering emulsions over an extended term disables human pancreatic cancer cell survival

    PubMed Central

    Wood, Kurt; Szewczuk, Myron R.; Rousseau, Dérick; Neufeld, Ronald J.

    2018-01-01

    Pickering emulsions are colloidal dispersions stabilized by particles that either migrate to, or are formed at, the oil-water interface during emulsification. Here, we fabricated and characterized Pickering water-in-oil emulsions where molten glycerol monostearate crystallized at the surface of micron-sized water droplets and formed protective solid shells. We tested this emulsion as a reservoir delivery platform for the sustained release of low molecular weight hydrophilic molecules including sodium chloride (NaCl) and sodium citrate as model compounds, and the therapeutic oseltamivir phosphate (OP), the delivery of which was the ultimate goal of this research. The objective was to achieve long-term (30-day) release of challenging to encapsulate actives and ultimately demonstrate the sustained release of OP for 20–30 days from an injectable formulation. OP was used because of its anticancer properties targeting mammalian neuraminidase 1 (Neu1) involved in multistage tumorigenesis. All actives including OP encapsulated in Pickering emulsions displayed a near linear release profile over 30 days. It was demonstrated that the release could be modulated by the addition of a second, competing surfactant sorbitan monooleate, Span 80, to the emulsion at levels above its critical micelle concentration. OP released from the emulsions significantly reduced cell viability in the human PANC-1 pancreatic cancer cell line for up to 30 days. The findings from this study indicate a simple, potentially injectable formulation and method that is easily upscaled resulting in a stable product with the potential to fully retain small hydrophilic molecules/drugs for sustained, near linear release over days, weeks, and potentially months. PMID:29560107

  12. Linear glandular trichomes of Helianthus (Asteraceae): morphology, localization, metabolite activity and occurrence

    PubMed Central

    Aschenbrenner, Anna-Katharina; Horakh, Silke; Spring, Otmar

    2013-01-01

    Capitate glandular trichomes of sunflower are well investigated, but detailed studies are lacking for the linear glandular trichomes (LGT), a second type of physiologically active plant hair present on the surface of sunflowers. Light, fluorescence and scanning electron microscopy as well as histochemical staining were used to investigate the structure and metabolite deposition of LGT. Consisting of 6–11 linearly arranged cells, LGT were found on the surface of most plant organs of Helianthus annuus. They were associated with the leaf vascular system, and also occurred along petioles, stems and the abaxial surface of chaffy bracts, ray and disc florets. The highest density was found on the abaxial surface of phyllaries. Phenotypically similar LGT were common in all species of the genus, but also occurred in most other genera of the Helianthinae so far screened. Brownish and fluorescent metabolites of an as yet unknown chemical structure, together with terpenoids, were produced and stored in apical cells of LGT. The deposition of compounds gradually progressed from the tip cell to the basal cells of older trichomes. This process was accompanied by nucleus degradation in metabolite-accumulating cells. The localization of these trichomes on prominent plant parts of the apical bud and the capitulum combined with the accumulation of terpenoids and other as yet unknown compounds suggests a chemo-ecological function of the LGT in plant–insect or plant–herbivore interaction.

  13. Effect of storage time on metabolite profile and alpha-glucosidase inhibitory activity of Cosmos caudatus leaves - GCMS based metabolomics approach.

    PubMed

    Javadi, Neda; Abas, Faridah; Mediani, Ahmed; Abd Hamid, Azizah; Khatib, Alfi; Simoh, Sanimah; Shaari, Khozirah

    2015-09-01

    Cosmos caudatus, which is a commonly consumed vegetable in Malaysia, is locally known as "Ulam Raja". It is a local Malaysian herb traditionally used as a food and medicinal herb to treat several maladies. Its bioactive or nutritional constituents consist of a wide range of metabolites, including glucosinolates, phenolics, amino acids, organic acids, and sugars. However, many of these metabolites are not stable and easily degraded or modified during storage. In order to investigate the metabolomics changes occurring during post-harvest storage, C. caudatus samples were subjected to seven different storage times (0 hours, 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, and 12 hours) at room temperature. As the model experiment, the metabolites identified by gas chromatography-mass spectrometry (GC-MS) were correlated with α-glucosidase inhibitory activity analyzed with multivariate data analysis (MVDA) to find out the variation among samples and metabolites contributing to the activity. Orthogonal partial least squares (OPLS) analysis was applied to investigate the metabolomics changes. A profound chemical alteration, both in primary and secondary metabolites, was observed. The α-tocopherol, catechin, cyclohexen-1-carboxylic acid, benzoic acid, myo-inositol, stigmasterol, and lycopene compounds were found to be the discriminating metabolites at early storage; however, sugars such as sucrose, α-d-galactopyranose, and turanose were detected, which was attributed to the discriminating metabolites for late storage. The result shows that the MVDA method is a promising technique to identify biomarker compounds relative to storage at different times. Copyright © 2015. Published by Elsevier B.V.

  14. Activation of the Dormant Secondary Metabolite Production by Introducing Gentamicin-Resistance in a Marine-Derived Penicillium purpurogenum G59

    PubMed Central

    Chai, Yun-Jing; Cui, Cheng-Bin; Li, Chang-Wei; Wu, Chang-Jing; Tian, Cong-Kui; Hua, Wei

    2012-01-01

    A new approach to activate silent gene clusters for dormant secondary metabolite production has been developed by introducing gentamicin-resistance to an originally inactive, marine-derived fungal strain Penicillium purpurogenum G59. Upon treatment of the G59 spores with a high concentration of gentamicin in aqueous DMSO, a total of 181 mutants were obtained by single colony isolation. In contrast to the strain G59, the EtOAc extracts of nine mutant cultures showed inhibitory effects on K562 cells, indicating that the nine mutants had acquired capability to produce antitumor metabolites. This was evidenced by TLC and HPLC analysis of EtOAc extracts of G59 and the nine mutants. Further isolation and characterization demonstrated that four antitumor secondary metabolites, janthinone (1), fructigenine A (2), aspterric acid methyl ester (3) and citrinin (4), were newly produced by mutant 5-1-4 compared to the parent strain G59, and which were also not found in the secondary metabolites of other Penicillium purpurogenum strains. However, Compounds 1–4 inhibited the proliferation of K562 cells with inhibition rates of 34.6% (1), 60.8% (2), 31.7% (3) and 67.1% (4) at 100 μg/mL, respectively. The present study demonstrated the effectiveness of a simple, yet practical approach to activate the production of dormant fungal secondary metabolites by introducing acquired resistance to aminoglycoside antibiotics, which could be applied to the studies for eliciting dormant metabolic potential of fungi to obtain cryptic secondary metabolites. PMID:22611354

  15. Actions of incretin metabolites on locomotor activity, cognitive function and in vivo hippocampal synaptic plasticity in high fat fed mice.

    PubMed

    Porter, David; Faivre, Emilie; Flatt, Peter R; Hölscher, Christian; Gault, Victor A

    2012-05-01

    The incretin hormones glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) improve markers of cognitive function in obesity-diabetes, however, both are rapidly degraded to their major metabolites, GLP-1(9-36)amide and GIP(3-42), respectively. Therefore, the present study investigated effects of GLP-1(9-36)amide and GIP(3-42) on locomotor activity, cognitive function and hippocampal synaptic plasticity in mice with diet-induced obesity and insulin resistance. High-fat fed Swiss TO mice treated with GLP-1(9-36)amide, GIP(3-42) or exendin(9-39)amide (twice-daily for 60 days) did not exhibit any changes in bodyweight, non-fasting plasma glucose and plasma insulin concentrations or glucose tolerance compared with high-fat saline controls. Similarly, locomotor and feeding activity, O(2) consumption, CO(2) production, respiratory exchange ratio and energy expenditure were not altered by chronic treatment with incretin metabolites. Administration of the truncated metabolites did not alter general behavior in an open field test or learning and memory ability as recorded during an object recognition test. High-fat mice exhibited a significant impairment in hippocampal long-term potentiation (LTP) which was not affected by treatment with incretin metabolites. These data indicate that incretin metabolites do not influence locomotor activity, cognitive function and hippocampal synaptic plasticity when administered at pharmacological doses to mice fed a high-fat diet. Copyright © 2012 Elsevier Inc. All rights reserved.

  16. Screening of marine fungus from Nanji Island and activity of their metabolites against pathogenic Vibrio from Pseudosciaena crocea

    NASA Astrophysics Data System (ADS)

    Zhao, Shujiang; Li, Shuping; Liu, Huihui; Zhao, Qian; Wang, Jieyou; Yan, Maocang

    2012-09-01

    Seventy-eight marine fungal strains were isolated from sediment samples collected off the coast of Nanji Island, Wenzhou, Zhejiang Province, China. Antibacterial screening using the agar disc method showed that 19 of the isolated strains could inhibit at least one pathogenic V ibrio from P seudosciaena crocea. Subsequent screening confirmed that nine strains produced antibacterial metabolites that had activity against one or several types of pathogenic V ibrio. Strain NJ0104 had the widest antimicrobial spectrum and strong activity, particularly against Vibrio parahaemolyticus-MM0810072. A preliminary study of NJ0104 antibacterial metabolites demonstrated that they had thermal stability up to 80°C, ultraviolet stability up to 40 min and pH stability between 4.0-7.0. In addition, the antibacterial metabolites were readily soluble in butanol. To identify the specific strain, the ITS-5.8S rDNA regions of NJ0104 were PCR amplified and sequenced. Based on the combination of phenotypic and genotypic data, the strain was identified as Arthrinium sp.

  17. In vitro antiprogestational/antiglucocorticoid activity and progestin and glucocorticoid receptor binding of the putative metabolites and synthetic derivatives of CDB-2914, CDB-4124, and mifepristone.

    PubMed

    Attardi, Barbara J; Burgenson, Janet; Hild, Sheri A; Reel, Jerry R

    2004-03-01

    In determining the biological profiles of various antiprogestins, it is important to assess the hormonal and antihormonal activity, selectivity, and potency of their proximal metabolites. The early metabolism of mifepristone is characterized by rapid demethylation and hydroxylation. Similar initial metabolic pathways have been proposed for CDB-2914 (CDB: Contraceptive Development Branch of NICHD) and CDB-4124, and their putative metabolites have been synthesized. We have examined the functional activities and potencies, in various cell-based assays, and relative binding affinities (RBAs) for progesterone receptors (PR) and glucocorticoid receptors (GR) of the putative mono- and didemethylated metabolites of CDB-2914, CDB-4124, and mifepristone and of the 17alpha-hydroxy and aromatic A-ring derivatives of CDB-2914 and CDB-4124. The binding affinities of the monodemethylated metabolites for rabbit uterine PR and human PR-A and PR-B were similar to those of the parent compounds. Monodemethylated mifepristone bound to rabbit thymic GR with higher affinity than monodemethylated CDB-2914 or CDB-4124. T47D-CO cells were used to assess inhibition of R5020-stimulated endogenous alkaline phosphatase activity and transactivation of the PRE(2)-thymidine kinase (tk)-luciferase (LUC) reporter plasmid in transient transfections. The antiprogestational potency was as follows: mifepristone/CDB-2914/CDB-4124/monodemethylated metabolites (IC(50)'s approximately 10(-9)M) > aromatic A-ring derivatives (IC(50)'s approximately 10(-8)M) > didemethylated/17alpha-hydroxy derivatives (IC(50)'s approximately 10(-7)M). Antiglucocorticoid activity was determined by inhibition of dexamethasone-stimulated transcriptional activity in HepG2 cells. The mono- and didemethylated metabolites of CDB-2914 and CDB-4124 had less antiglucocorticoid activity (IC(50)'s approximately 10(-6)M) than monodemethylated mifepristone (IC(50) approximately 10(-8)M) or the other test compounds. At 10(-6)M in

  18. Allocation of secondary metabolites, photosynthetic capacity, and antioxidant activity of Kacip Fatimah (Labisia pumila Benth) in response to CO2 and light intensity.

    PubMed

    Ibrahim, Mohd Hafiz; Jaafar, Hawa Z E; Karimi, Ehsan; Ghasemzadeh, Ali

    2014-01-01

    A split plot 3 by 4 experiment was designed to investigate and distinguish the relationships among production of secondary metabolites, soluble sugar, phenylalanine ammonia lyase (PAL; EC 4.3.1.5) activity, leaf gas exchange, chlorophyll content, antioxidant activity (DPPH), and lipid peroxidation under three levels of CO2 (400, 800, and 1200 μ mol/mol) and four levels of light intensity (225, 500, 625, and 900 μ mol/m(2)/s) over 15 weeks in Labisia pumila. The production of plant secondary metabolites, sugar, chlorophyll content, antioxidant activity, and malondialdehyde content was influenced by the interactions between CO2 and irradiance. The highest accumulation of secondary metabolites, sugar, maliondialdehyde, and DPPH activity was observed under CO2 at 1200 μ mol/mol + light intensity at 225 μ mol/m(2)/s. Meanwhile, at 400 μ mol/mol CO2 + 900 μ mol/m(2)/s light intensity the production of chlorophyll and maliondialdehyde content was the highest. As CO2 levels increased from 400 to 1200 μ mol/mol the photosynthesis, stomatal conductance, f v /f m (maximum efficiency of photosystem II), and PAL activity were enhanced. The production of secondary metabolites displayed a significant negative relationship with maliondialdehyde indicating lowered oxidative stress under high CO2 and low irradiance improved the production of plant secondary metabolites that simultaneously enhanced the antioxidant activity (DPPH), thus improving the medicinal value of Labisia pumila under this condition.

  19. Trichloroethylene and Its Oxidative Metabolites Enhance the Activated State and Th1 Cytokine Gene Expression in Jurkat Cells.

    PubMed

    Pan, Yao; Wei, Xuetao; Hao, Weidong

    2015-08-28

    Trichloroethylene (TCE) is an occupational and ubiquitous environmental contaminant, and TCE exposure will increase the risk of autoimmune diseases and allergic diseases. T cells play an important role in the pathogenesis of TCE-related immune disorders, but the effect of TCE and its oxidative metabolites, trichloroacetic acid (TCA) and dichloroacetic acid (DCA), on the activation of human T cells is still unknown. In this study, Jurkat cells were pre-treated with TCE, TCA and DCA overnight and then stimulated with phorbol 12-myristate 13-acetate and ionomycin for another 4, 8 and 24 hours. IL-2 secretion was detected by ELISA; the expressions of CD25 and CD69 were tested by flow cytometry; and IFN-γ and IL-2 mRNA expression levels were investigated by real-time PCR. The results showed that TCE and its oxidative metabolites, TCA and DCA, significantly enhanced IL-2 releasing and the expression of T cell activation markers, CD25 and CD69. Consistent with this result, these compounds markedly up-regulated the expression levels of IFN-γ and IL-2 mRNA. Collectively, these findings suggest that TCE and its metabolites, TCA and DCA, might enhance the activation of T cells and disrupt various activities of peripheral T cells.

  20. Trichloroethylene and Its Oxidative Metabolites Enhance the Activated State and Th1 Cytokine Gene Expression inJurkat Cells

    PubMed Central

    Pan, Yao; Wei, Xuetao; Hao, Weidong

    2015-01-01

    Trichloroethylene (TCE) is an occupational and ubiquitous environmental contaminant, and TCE exposure will increase the risk of autoimmune diseases and allergic diseases. T cells play an important role in the pathogenesis of TCE-related immune disorders, but the effect of TCE and its oxidative metabolites, trichloroacetic acid (TCA) and dichloroacetic acid (DCA), on the activation of human T cells is still unknown. In this study, Jurkat cells were pre-treated with TCE, TCA and DCA overnight and then stimulated with phorbol 12-myristate 13-acetate and ionomycin for another 4, 8 and 24 hours. IL-2 secretion was detected by ELISA; the expressions of CD25 and CD69 were tested by flow cytometry; and IFN-γ and IL-2 mRNA expression levels were investigated by real-time PCR. The results showed that TCE and its oxidative metabolites, TCA and DCA, significantly enhanced IL-2 releasing and the expression of T cell activation markers, CD25 and CD69. Consistent with this result, these compounds markedly up-regulated the expression levels of IFN-γ and IL-2 mRNA. Collectively, these findings suggest that TCE and its metabolites, TCA and DCA, might enhance the activation of T cells and disrupt various activities of peripheral T cells. PMID:26343699

  1. [Secondary metabolites, lethality and antimicrobial activity of extracts from three corals and three marine mollusks from Sucre, Venezuela].

    PubMed

    Ordaz, Gabriel; D'Armas, Haydelba; Yáñez, Dayanis; Hernández, Juan; Camacho, Angel

    2010-06-01

    The study of biochemical activity of extracts obtained from marine organisms is gaining interest as some have proved to have efficient health or industrial applications. To evaluate lethality and antimicrobial activities, some chemical tests were performed on crude extracts of the octocorals Eunicea sp., Muricea sp. and Pseudopterogorgia acerosa and the mollusks Pteria colymbus, Phyllonotus pomum and Chicoreus brevifrons, collected in Venezuelan waters. The presence of secondary metabolites like alkaloids, unsaturated sterols and pentacyclic triterpenes in all invertebrates, was evidenced. Additionally, sesquiterpenlactones, saponins, tannins, cyanogenic and cardiotonic glycosides were also detected in some octocoral extracts, suggesting that biosynthesis of these metabolites is typical in this group. From the lethality bioassays, all extracts resulted lethal to Artemia salina (LC50<1000 microg/ml) with an increased of lethal activity with exposition time. P. pomum extract showed the highest lethality rate (LC50=46.8 microg/ml). Compared to the octocorals, mollusks extracts displayed more activity and a greater action spectrum against different bacterial strains, whereas octocorals also inhibited some fungi strains growth. Staphylococcus aureus was the most susceptible to the antimicrobial power of the extracts (66.7%), whereas Pseudomonas aeruginosa, Candida albicans and Aspergillus niger were not affected. The antibiosis shown by marine organisms extracts indicates that some of their biosynthesized metabolites are physiologically active, and may have possible cytotoxic potential or as a source of antibiotic components.

  2. Discover binding pathways using the sliding binding-box docking approach: application to binding pathways of oseltamivir to avian influenza H5N1 neuraminidase

    NASA Astrophysics Data System (ADS)

    Tran, Diem-Trang T.; Le, Ly T.; Truong, Thanh N.

    2013-08-01

    Drug binding and unbinding are transient processes which are hardly observed by experiment and difficult to analyze by computational techniques. In this paper, we employed a cost-effective method called "pathway docking" in which molecular docking was used to screen ligand-receptor binding free energy surface to reveal possible paths of ligand approaching protein binding pocket. A case study was applied on oseltamivir, the key drug against influenza a virus. The equilibrium pathways identified by this method are found to be similar to those identified in prior studies using highly expensive computational approaches.

  3. Comparative evaluation of two Trichoderma harzianum strains for major secondary metabolite production and antifungal activity.

    PubMed

    Ahluwalia, Vivek; Kumar, Jitendra; Rana, Virendra S; Sati, Om P; Walia, S

    2015-01-01

    This investigation was undertaken to identify the major secondary metabolite, produced by two Trichoderma harzianum strains (T-4 and T-5) with their antifungal activity against phytopathogenic fungi using poison food technique. The ethyl acetate extract was subjected to column chromatography using n-hexane, ethyl acetate and methanol gradually. Chromatographic separation of ethyl acetate extract of T. harzianum (T-4) resulted in the isolation and identification of palmitic acid (1), 1,8-dihydroxy-3-methylanthraquinone (2), 6-pentyl-2H-pyran-2-one (3), 2(5H)-furanone (4), stigmasterol (5) and β-sitosterol (6), while T. harzianum (T-5) gave palmitic acid (1), 1-hydroxy-3-methylanthraquinone (7), δ-decanolactone (8), 6-pentyl-2H-pyran-2-one (3), ergosterol (9), harzianopyridone (10) and 6-methyl-1,3,8-trihydroxyanthraquinone (11) as major metabolites. Among compounds screened for antifungal activity, compound 10 was found to be most active (EC50 35.9-50.2 μg mL(-1)). In conclusion, the present investigation provided significant information about antifungal activity and compounds isolated from two different strains of T. harzianum obtained from two different Himalayan locations.

  4. Biosynthesis of human diazepam and clonazepam metabolites.

    PubMed

    de Paula, Núbia C; Araujo Cordeiro, Kelly C F; de Melo Souza, Paula L; Nogueira, Diogo F; da Silva e Sousa, Diego B; Costa, Maísa B; Noël, François; de Oliveira, Valéria

    2015-03-01

    A screening of fungal and microbial strains allowed to select the best microorganisms to produce in high yields some of the human metabolites of two benzodiazepine drugs, diazepam and clonazepam, in order to study new pharmacological activities and for chemical standard proposes. Among the microorganisms tested, Cunninghamella echinulata ATCC 9244 and Rhizopus arrhizus ATCC 11145 strains, were the most active producers of the mains metabolites of diazepam which included demethylated, hydroxylated derivatives. Beauveria bassiana ATCC 7159 and Chaetomium indicum LCP 984200 produced the 7 amino-clonazepam metabolite and a product of acid hydrolysis of this benzodiazepine. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Antitrypanosomal Activity of Fexinidazole Metabolites, Potential New Drug Candidates for Chagas Disease

    PubMed Central

    Nascimento, Alvaro F. S.; Mazzeti, Ana Lia; Marques, Luiz F.; Gonçalves, Karolina R.; Mota, Ludmilla W. R.; Diniz, Lívia de F.; Caldas, Ivo S.; Talvani, André; Shackleford, David M.; Koltun, Maria; Saunders, Jessica; White, Karen L.; Scandale, Ivan; Charman, Susan A.; Chatelain, Eric

    2014-01-01

    This study was designed to verify the in vivo efficacy of sulfoxide and sulfone fexinidazole metabolites following oral administration in a murine model of Chagas disease. Female Swiss mice infected with the Y strain of Trypanosoma cruzi were treated orally once per day with each metabolite at doses of 10 to 100 mg/kg of body weight for a period of 20 days. Parasitemia was monitored throughout, and cures were detected by parasitological and PCR assays. The results were compared with those achieved with benznidazole treatment at the same doses. Fexinidazole metabolites were effective in reducing the numbers of circulating parasites and protecting mice against death, compared with untreated mice, but without providing cures at daily doses of 10 and 25 mg/kg. Both metabolites were effective in curing mice at 50 mg/kg/day (30% to 40%) and 100 mg/kg/day (100%). In the benznidazole-treated group, parasitological cure was detected only in animals treated with the higher dose of 100 mg/kg/day (80%). Single-dose pharmacokinetic parameters for each metabolite were obtained from a parallel group of uninfected mice and were used to estimate the profiles following repeated doses. Pharmacokinetic data suggested that biological efficacy most likely resides with the sulfone metabolite (or subsequent reactive metabolites formed following reduction of the nitro group) following administration of either the sulfoxide or the sulfone and that prolonged plasma exposure over the 24-h dosing window is required to achieve high cure rates. Fexinidazole metabolites were effective in treating T. cruzi in a mouse model of acute infection, with cure rates superior to those achieved with either fexinidazole itself or benznidazole. PMID:24841257

  6. Microsomal metabolism of trenbolone acetate metabolites ...

    EPA Pesticide Factsheets

    Trenbolone acetate (TBA) is a synthetic growth promoter widely used in animal agriculture, and its metabolites are suspected endocrine disrupting compounds in agriculturally impacted receiving waters. However, beyond the three widely recognized TBA metabolites (17-trenbolone, 17-trenbolone and trendione), little is known about other metabolites formed in vivo and subsequently discharged into the environment, with some evidence suggesting these unknown metabolites comprise a majority of the TBA mass dosed to the animal. Here, we explored the metabolism of the three known TBA metabolites using rat liver microsome studies. All TBA metabolites are transformed into a complex mixture of monohydroxylated products. Based on product characterization, the majority are more polar than the parent metabolites but maintain their characteristic trienone backbone. A minor degree of interconversion between known metabolites was also observed, as were higher order hydroxylated products with a greater extent of reaction. Notably, the distribution and yield of products were generally comparable across a series of variably induced rat liver microsomes, as well as during additional studies with human and bovine liver microsomes. Bioassays conducted with mixtures of these transformation products suggest that androgen receptor (AR) binding activity is diminished as a result of the microsomal treatment, suggesting that the transformation products are generally less potent than

  7. Activation of cryptic metabolite production through gene disruption: Dimethyl furan-2,4-dicarboxylate produced by Streptomyces sahachiroi.

    PubMed

    Simkhada, Dinesh; Zhang, Huitu; Mori, Shogo; Williams, Howard; Watanabe, Coran M H

    2013-01-01

    At least 65% of all small molecule drugs on the market today are natural products, however, re-isolation of previously identified and characterized compounds has become a serious impediment to the discovery of new bioactive natural products. Here, genetic knockout of an unusual non-ribosomal peptide synthetase (NRPS) C-PCP-C module, aziA2, is performed resulting in the accumulation of the secondary metabolite, dimethyl furan-2,4-dicarboxylate. The cryptic metabolite represents the first non-azinomycin related compound to be isolated and characterized from the soil bacterium, S. sahachiroi. The results from this study suggest that abolishing production of otherwise predominant natural products through genetic knockout may constitute a means to "activate" the production of novel secondary metabolites that would otherwise lay dormant within microbial genome sequences.

  8. Biotransformation of Bisphenol AF to Its Major Glucuronide Metabolite Reduces Estrogenic Activity

    PubMed Central

    Yin, Jie; Zhang, Jing; Feng, Yixing; Shao, Bing

    2013-01-01

    Bisphenol AF (BPAF), an endocrine disrupting chemical, can induce estrogenic activity through binding to estrogen receptor (ER). However, the metabolism of BPAF in vivo and the estrogenic activity of its metabolites remain unknown. In the present study, we identified four metabolites including BPAF diglucuronide, BPAF glucuronide (BPAF-G), BPAF glucuronide dehydrated and BPAF sulfate in the urine of Sprague-Dawley (SD) rats. BPAF-G was further characterized by nuclear magnetic resonance (NMR). After treatment with a single dose of BPAF, BPAF was metabolized rapidly to BPAF-G, as detected in the plasma of SD rats. Biotransformation of BPAF to BPAF-G was confirmed with human liver microsomes (HLM), and Vmax of glucuronidation for HLM was 11.6 nmol/min/mg. We also found that BPAF glucuronidation could be mediated through several human recombinant UDP-glucuronosyltransferases (UGTs) including UGT1A1, UGT1A3, UGT1A8, UGT1A9, UGT2B4, UGT2B7, UGT2B15 and UGT2B17, among which UGT2B7 showed the highest efficiency of glucuronidation. To explain the biological function of BPAF biotransformation, the estrogenic activities of BPAF and BPAF-G were evaluated in ER-positive breast cancer T47D and MCF7 cells. BPAF significantly stimulates ER-regulated gene expression and cell proliferation at the dose of 100 nM and 1 μM in breast cancer cells. However, BPAF-G did not show any induction of estrogenic activity at the same dosages, implying that formation of BPAF-G is a potential host defense mechanism against BPAF. Based on our study, biotransformation of BPAF to BPAF-G can eliminate BPAF-induced estrogenic activity, which is therefore considered as reducing the potential threat to human beings. PMID:24349450

  9. Discovery of berberine based derivatives as anti-influenza agent through blocking of neuraminidase.

    PubMed

    Enkhtaivan, Gansukh; Muthuraman, Pandurangan; Kim, Doo Hwan; Mistry, Bhupendra

    2017-10-15

    In this study, we investigated the antiviral activity of newly synthesized berberine derivatives (BD) against influenza virus infection using several strains in in vitro and in silico. The CPE reduction, pre-incubation, NA activity inhibition and molecular docking assays were used for antiviral evaluation. The anti-influenza activities of BDs were stronger than plant-derived pure commercial berberine, and some of the BDs were more potent than control drug Oseltamivir. The cytotoxicity level was observed in the range 63.16-1639μg/mL for synthesized BDs. Additionally, BDs were detected as able to block influenza viral particles. We targeted neuraminidase one of the influenza surface protein for further probing. Moreover, BDs registered competitive NA inhibition activity comparing with Oseltamivir. The active site of viral NA subunit was fully blocked by BD as the same location as Oseltamivir. The binding energies between influenza NA subunit and BD-5 were higher than Oseltamivir. More H-bonds and NA residues were occupied by BD for stronger binding ability than Oseltamivir. These results indicated that BD inhibits various strains of influenza virus by blocking of viral NA subunit. Copyright © 2017. Published by Elsevier Ltd.

  10. Limited brain distribution of [3R,4R,5S]-4-acetamido-5-amino-3-(1-ethylpropoxy)-1-cyclohexene-1-carboxylate phosphate (Ro 64-0802), a pharmacologically active form of oseltamivir, by active efflux across the blood-brain barrier mediated by organic anion transporter 3 (Oat3/Slc22a8) and multidrug resistance-associated protein 4 (Mrp4/Abcc4).

    PubMed

    Ose, Atsushi; Ito, Mototsugu; Kusuhara, Hiroyuki; Yamatsugu, Kenzo; Kanai, Motomu; Shibasaki, Masakatsu; Hosokawa, Masakiyo; Schuetz, John D; Sugiyama, Yuichi

    2009-02-01

    [3R,4R,5S]-4-Acetamido-5-amino-3-(1-ethylpropoxy)-1-cyclohexene-1-carboxylate phosphate (Ro 64-0802) is a pharmacologically active form of the anti-influenza virus drug oseltamivir. Abnormal behavior is a suspected adverse effect of oseltamivir on the central nervous system. This study focused on the transport mechanisms of Ro 64-0802 across the blood-brain barrier (BBB). Ro 64-0802 was found to be a substrate of organic anion transporter 3 (OAT3/SLC22A8) and multidrug resistance-associated protein 4 (MRP4/ABCC4). Human embryonic kidney 293 cells expressing OAT3 exhibited a greater intracellular accumulation of Ro 64-0802 than mock-transfected cells (15 versus 1.2 microl/mg protein/10 min, respectively). The efflux of Ro 64-0802 was 3-fold greater when MRP4 was expressed in MDCKII cells and was significantly inhibited by indomethacin. After its microinjection into the cerebrum, the amount of Ro 64-0802 in brain was significantly greater in both Oat3(-/-) mice and Mrp4(-/-) mice compared with the corresponding wild-type mice (0.36 versus 0.080 and 0.32 versus 0.060 nmol at 120 min after injection, respectively). The brain/plasma concentration ratio (K(p,) (brain)) of Ro 64-0802, determined in wild-type mice after subcutaneous continuous infusion for 24 h, was close to the capillary volume (approximately 10 microl/g brain). Although the K(p,) (brain) of Ro 64-0802 was unchanged in Oat3(-/-) mice, it was significantly greater in Mrp4(-/-) mice (41 microl/g of brain). These results suggest that Ro 64-0802 can cross the BBB from the blood, but its brain distribution is limited by its active efflux by Mrp4 and Oat3 across the BBB. The transporter responsible for the brain uptake of Ro 64-0802 remains unknown, but Oat3 is a candidate transporter.

  11. Allocation of Secondary Metabolites, Photosynthetic Capacity, and Antioxidant Activity of Kacip Fatimah (Labisia pumila Benth) in Response to CO2 and Light Intensity

    PubMed Central

    Jaafar, Hawa Z. E.; Karimi, Ehsan; Ghasemzadeh, Ali

    2014-01-01

    A split plot 3 by 4 experiment was designed to investigate and distinguish the relationships among production of secondary metabolites, soluble sugar, phenylalanine ammonia lyase (PAL; EC 4.3.1.5) activity, leaf gas exchange, chlorophyll content, antioxidant activity (DPPH), and lipid peroxidation under three levels of CO2 (400, 800, and 1200 μmol/mol) and four levels of light intensity (225, 500, 625, and 900 μmol/m2/s) over 15 weeks in Labisia pumila. The production of plant secondary metabolites, sugar, chlorophyll content, antioxidant activity, and malondialdehyde content was influenced by the interactions between CO2 and irradiance. The highest accumulation of secondary metabolites, sugar, maliondialdehyde, and DPPH activity was observed under CO2 at 1200 μmol/mol + light intensity at 225 μmol/m2/s. Meanwhile, at 400 μmol/mol CO2 + 900 μmol/m2/s light intensity the production of chlorophyll and maliondialdehyde content was the highest. As CO2 levels increased from 400 to 1200 μmol/mol the photosynthesis, stomatal conductance, f v/f m (maximum efficiency of photosystem II), and PAL activity were enhanced. The production of secondary metabolites displayed a significant negative relationship with maliondialdehyde indicating lowered oxidative stress under high CO2 and low irradiance improved the production of plant secondary metabolites that simultaneously enhanced the antioxidant activity (DPPH), thus improving the medicinal value of Labisia pumila under this condition. PMID:24683336

  12. GC-MS-based metabolite profiling of Cosmos caudatus leaves possessing alpha-glucosidase inhibitory activity.

    PubMed

    Javadi, Neda; Abas, Faridah; Abd Hamid, Azizah; Simoh, Sanimah; Shaari, Khozirah; Ismail, Intan Safinar; Mediani, Ahmed; Khatib, Alfi

    2014-06-01

    Cosmos caudatus, which is known as "Ulam Raja," is an herbal plant used in Malaysia to enhance vitality. This study focused on the evaluation of the α-glucosidase inhibitory activity of different ethanolic extracts of C. caudatus. Six series of samples extracted with water, 20%, 40%, 60%, 80%, and 100% ethanol (EtOH) were employed. Gas chromatography-mass spectrometry (GC-MS) and orthogonal partial least-squares (OPLS) analysis was used to correlate bioactivity of different extracts to different metabolite profiles of C. caudatus. The obtained OPLS scores indicated a distinct and remarkable separation into 6 clusters, which were indicative of the 6 different ethanol concentrations. GC-MS can be integrated with multivariate data analysis to identify compounds that inhibit α-glucosidase activity. In addition, catechin, α-linolenic acid, α-D-glucopyranoside, and vitamin E compounds were identified and indicate the potential α-glucosidase inhibitory activity of this herb. GC-MS and multivariate data analysis was applied to discriminate Cosmos caudatus samples extracted with water and different ratio of ethanol. Orthogonal partial least-squares (OPLS) model developed was used to determine the major metabolites contributed to α-glucosidase inhibitory activity. This approach also has the ability to predict the bioactivity of a new set of extracts based on a developed validated regression model that is important for quality control of the herb preparation. © 2014 Institute of Food Technologists®

  13. Production of Secondary Metabolites in Extreme Environments: Food- and Airborne Wallemia spp. Produce Toxic Metabolites at Hypersaline Conditions

    PubMed Central

    Frisvad, Jens C.; Kocev, Dragi; Džeroski, Sašo; Gunde-Cimerman, Nina

    2016-01-01

    The food- and airborne fungal genus Wallemia comprises seven xerophilic and halophilic species: W. sebi, W. mellicola, W. canadensis, W. tropicalis, W. muriae, W. hederae and W. ichthyophaga. All listed species are adapted to low water activity and can contaminate food preserved with high amounts of salt or sugar. In relation to food safety, the effect of high salt and sugar concentrations on the production of secondary metabolites by this toxigenic fungus was investigated. The secondary metabolite profiles of 30 strains of the listed species were examined using general growth media, known to support the production of secondary metabolites, supplemented with different concentrations of NaCl, glucose and MgCl2. In more than two hundred extracts approximately one hundred different compounds were detected using high-performance liquid chromatography-diode array detection (HPLC-DAD). Although the genome data analysis of W. mellicola (previously W. sebi sensu lato) and W. ichthyophaga revealed a low number of secondary metabolites clusters, a substantial number of secondary metabolites were detected at different conditions. Machine learning analysis of the obtained dataset showed that NaCl has higher influence on the production of secondary metabolites than other tested solutes. Mass spectrometric analysis of selected extracts revealed that NaCl in the medium affects the production of some compounds with substantial biological activities (wallimidione, walleminol, walleminone, UCA 1064-A and UCA 1064-B). In particular an increase in NaCl concentration from 5% to 15% in the growth media increased the production of the toxic metabolites wallimidione, walleminol and walleminone. PMID:28036382

  14. Trichoderma secondary metabolites that affect plant metabolism.

    PubMed

    Vinale, Francesco; Sivasithamparam, Krishnapillai; Ghisalberti, Emilio L; Ruocco, Michelina; Wood, Sheridan; Lorito, Matteo

    2012-11-01

    Recently, there have been many exciting new developments relating to the use of Trichoderma spp. as agents for biocontrol of pathogens and as plant growth promoters. Several mechanisms have been proposed to explain the positive effects of these microorganisms on the plant host. One factor that contributes to their beneficial biological activities is related to the wide variety of metabolites that they produce. These metabolites have been found not only to directly inhibit the growth and pathogenic activities of the parasites, but also to increase disease resistance by triggering the system of defence in the plant host. In addition, these metabolites are also capable of enhancing plant growth, which enables the plant to counteract the disease with compensatory vegetative growth by the augmented production of root and shoot systems. This review takes into account the Trichoderma secondary metabolites that affect plant metabolism and that may play an important role in the complex interactions of this biocontrol agent with the plant and pathogens.

  15. Flavone Biotransformation by Aspergillus niger and the Characterization of Two Newly Formed Metabolites

    PubMed Central

    Assawah, Suzan W.; El-Sharkawy, Saleh H.; Abdel-Salam, Amal

    2008-01-01

    Aspergillus niger isolated from Allium sativum was used at large scale fermentation (150 mg flavone/200 ml medium) to obtain suitable amounts of the products, efficient for identification. Then spectral analysis (UV, IR, 1H-NMR, 13C-NMR) and mass spectrometry were performed for the two products, which contributed to the identification process. The metabolite (1) was identified as 2'-hydroxydihydrochalcone, and the metabolite (2) was identified as 2'-hydroxyphenylmethylketone, which were more active than flavone itself. Antioxidant activities of the two isolated metabolites were tested compared with ascorbic acid. Antioxidant activity of metabolite (1) was recorded 64.58% which represented 79% of the antioxidant activity of ascorbic acid, and metabolite (2) was recorded 54.16% (67% of ascorbic acid activity). However, the antioxidant activity of flavone was recorded 37.50% which represented 46% of ascorbic acid activity. The transformed products of flavone have antimicrobial activity against Pseudomonas aeruginosa, Aspergillus flavus and Candida albicans, with MIC was recorded 250 µg/ml for metabolite (2) against all three organism and 500, 300, and 300 µg/ml for metabolite (1) against tested microorganisms (P. aeruginosa, Escherichia coli, Bacillus subtilis, and Klebsiella pneumonia, Fusarium moniliforme, A. flavus, Saccharomyces cerviceae, Kluveromyces lactis and C. albicans) at this order. PMID:23990746

  16. Mutagenic activity and metabolites in the urine of workers exposed to trinitrotoluene (TNT).

    PubMed Central

    Ahlborg, G; Einistö, P; Sorsa, M

    1988-01-01

    Urine samples taken after work and after a free weekend from 50 workers employed in various activities in a chemical plant manufacturing explosives were analysed. On the basis of hygienic surveys, the subjects were divided into three categories of exposure to trinitrotoluene (TNT). The urine analyses consisted of gas chromatographic identification of TNT and its two metabolites, 4-ADNT and 2-ADNT, and a determination of the mutagenic activity. Two frame shift detector strains of Salmonella typhimurium were used, TA 98 and TA 98 NR, the latter being deficient in endogenous nitroreductase activity. On the basis of previous results on TNT mutagenicity, no exogeneous metabolic system was used to test the urine concentrates. Both tester strains showed that the mean urinary mutagenic activity was higher in the after work samples than in post weekend samples from the same subjects, showing that bacterial nitroreductase activity was not significantly responsible for the mutagenicity, although the response was higher with strain TA 98 than with TA 98 NR. The interindividual variation in urine mutagenicity was high, however, and the difference between the two sampling times was statistically significant (p less than 0.05) only for the high exposed group (workers in trotyl foundry and sieve house). Correlation between urinary mutagenicity and concentration of TNT in urine was poor; correlation was significant only with the urinary concentration of 4-ADNT. The correlation between urinary TNT and both metabolites was good (p less than 0.001). These results suggest that analysis of 4-ADNT in urine would be a sufficient biological measure for controlling exposure to TNT. PMID:3378017

  17. Kynurenine pathway metabolites are associated with hippocampal activity during autobiographical memory recall in patients with depression.

    PubMed

    Young, Kymberly D; Drevets, Wayne C; Dantzer, Robert; Teague, T Kent; Bodurka, Jerzy; Savitz, Jonathan

    2016-08-01

    Inflammation-related changes in the concentrations of inflammatory mediators such as c-reactive protein (CRP), interleukin 1β (IL-1), and IL-6 as well as kynurenine metabolites are associated with major depressive disorder (MDD) and affect depressive behavior, cognition, and hippocampal plasticity in animal models. We previously reported that the ratios of kynurenic acid (KynA) to the neurotoxic metabolites, 3-hydroxykynurenine (3HK) and quinolinic acid (QA), were positively correlated with hippocampal volume in depression. The hippocampus is critical for autobiographical memory (AM) recall which is impaired in MDD. Here we tested whether the ratios, KynA/3HK and KynA/QA were associated with AM recall performance as well as hippocampal activity during AM recall. Thirty-five unmedicated depressed participants and 25 healthy controls (HCs) underwent fMRI scanning while recalling emotionally-valenced AMs and provided serum samples for the quantification of kynurenine metabolites, CRP, and cytokines (IL-1 receptor antagonist - IL-1RA; IL-6, tumor necrosis factor alpha - TNF, interferon gamma -IFN-γ, IL-10). KynA/3HK and KynA/QA were lower in the MDD group relative to the HCs. The concentrations of the CRP and the cytokines did not differ significantly between the HCs and the MDD group. Depressed individuals recalled fewer specific AMs and displayed increased left hippocampal activity during the recall of positive and negative memories. KynA/3HK was inversely associated with left hippocampal activity during specific AM recall in the MDD group. Further, KynA/QA was positively correlated with percent negative specific memories recalled in the MDD group and showed a non-significant trend toward a positive correlation with percent positive specific memories recalled in HCs. In contrast, neither CRP nor the cytokines were significantly associated with AM recall or activity of the hippocampus during AM recall. Conceivably, an imbalance in levels of KynA versus QA

  18. Baicalin and its metabolites suppresses gluconeogenesis through activation of AMPK or AKT in insulin resistant HepG-2 cells.

    PubMed

    Wang, Tao; Jiang, Hongmei; Cao, Shijie; Chen, Qian; Cui, Mingyuan; Wang, Zhijie; Li, Dandan; Zhou, Jing; Wang, Tao; Qiu, Feng; Kang, Ning

    2017-12-01

    Scutellaria baicalensis Georgi (S. baicalensis), as a traditional Chinese herbal medicine, is an important component of several famous Chinese medicinal formulas for treating patients with diabetes mellitus. Baicalin (BG), a main bioactive component of S. baicalensis, has been reported to have antidiabetic effects. However, pharmacokinetic studies have indicated that BG has poor oral bioavailability. Therefore, it is hard to explain the pharmacological effects of BG in vivo. Interestingly, several reports show that BG is extensively metabolized in rats and humans. Therefore, we speculate that the BG metabolites might be responsible for the pharmacological effects. In this study, BG and its three metabolites (M1-M3) were examined their effects on glucose consumption in insulin resistant HepG-2 cells with a commercial glucose assay kit. Real-time PCR and western blot assay were used to confirm genes and proteins of interest, respectively. The results demonstrate that BG and its metabolites (except for M3) enhanced the glucose consumption which might be associated with inhibiting the expression of the key gluconeogenic genes, including glucose-6-phosphatase (G6Pase), phosphoenolypyruvate carboxykinase (PEPCK) and glucose transporter 2 (GLUT2). Further study found that BG and M1 could suppress hepatic gluconeogenesis via activation of the AMPK pathway, while M2 could suppress hepatic gluconeogenesis via activation of the PI3K/AKT signaling pathway. Taken together, our findings suggest that both BG and its metabolites have antihyperglycemic activities, and might be the active forms of oral doses of BG in vivo. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  19. EFFECTS OF METHOPRENE, ITS METABOLITES, AND BREAKDOWN PRODUCTS ON RETINOID-ACTIVATED PATHWAYS IN TRANSFECTED CELL LINES

    EPA Science Inventory

    Methoprene is a terpene-based insecticide designed to act as an agonist of insect juvenile hormone, which is essential for the transition from larval to adult forms in some metamorphic insects. Recent evidence suggests that a methoprene metabolite, methoprene acid, activates a ve...

  20. Depsides: Lichen Metabolites Active against Hepatitis C Virus

    PubMed Central

    Vu, Thi Huyen; Le Lamer, Anne-Cécile; Lalli, Claudia; Boustie, Joël; Samson, Michel

    2015-01-01

    A thorough phytochemical study of Stereocaulon evolutum was conducted, for the isolation of structurally related atranorin derivatives. Indeed, pilot experiments suggested that atranorin (1), the main metabolite of this lichen, would interfere with the lifecycle of hepatitis C virus (HCV). Eight compounds, including one reported for the first time (2), were isolated and characterized. Two analogs (5, 6) were also synthesized, to enlarge the panel of atranorin-related structures. Most of these compounds were active against HCV, with a half-maximal inhibitory concentration of about 10 to 70 µM, with depsides more potent than monoaromatic phenols. The most effective inhibitors (1, 5 and 6) were then added at different steps of the HCV lifecycle. Interestingly, atranorin (1), bearing an aldehyde function at C-3, inhibited only viral entry, whereas the synthetic compounds 5 and 6, bearing a hydroxymethyl and a methyl function, respectively, at C-3 interfered with viral replication. PMID:25793970

  1. The Significance of Lichens and Their Metabolites

    NASA Astrophysics Data System (ADS)

    Huneck, S.

    Lichens, symbiontic organisms of fungi and algae, synthesize numerous metabolites, the "lichen substances," which comprise aliphatic, cycloaliphatic, aromatic, and terpenic compounds. Lichens and their metabolites have a manifold biological activity: antiviral, antibiotic, antitumor, allergenic, plant growth inhibitory, antiherbivore, and enzyme inhibitory. Usnic acid, a very active lichen substance is used in pharmaceutical preparations. Large amounts of Pseudevernia furfuracea and Evernia prunastri are processed in the perfume industry, and some lichens are sensitive reagents for the evaluation of air pollution.

  2. Insights into the mechanisms of Promysalin, a secondary metabolite with genus-specific antibacterial activity against Pseudomonas

    USDA-ARS?s Scientific Manuscript database

    Promysalin, a secondary metabolite produced by Pseudomonas putida RW10S1, has antibacterial activity against a wide variety of Pseudomonas sp., including both human and plant pathogens. Promysalin induces swarming and biofilm formation in the producing species, and inhibits growth of susceptible sp...

  3. New Pioglitazone Metabolites and Absence of Opened-Ring Metabolites in New N-Substituted Thiazolidinedione.

    PubMed

    Campos, Michel Leandro; Cerqueira, Letícia Bonancio; Silva, Bruna Cristina Ulian; Franchin, Taísa Busaranho; Galdino-Pitta, Marina Rocha; Pitta, Ivan Rocha; Peccinini, Rosângela Gonçalves; Pontarolo, Roberto

    2018-06-01

    Thiazolidinediones (TZDs) are drugs used to treat type 2 diabetes mellitus; however, several safety concerns remain regarding the available drugs in this class. Therefore, the search for new TZD candidates is ongoing; metabolism studies play a crucial step in the development of new candidates. Pioglitazone, one of the most commonly used TZDs, and GQ-11, a new N -substituted TZD, were investigated in terms of their metabolic activity in rat and human liver microsomes to assess their metabolic stability and investigate their metabolites. Methods for preparation of samples were based on liquid-liquid extraction and protein precipitation. Quantitation was performed using liquid chromatography (LC)-tandem mass spectrometry, and the metabolite investigation was performed using ultraperformance LC coupled to a hybrid quadrupole-time of flight mass spectrometer. The predicted intrinsic clearance of GQ-11 was 70.3 and 46.1 ml/kg per minute for rats and humans, respectively. The predicted intrinsic clearance of pioglitazone was 24.1 and 15.9 ml/kg per minute for rats and humans, respectively. The pioglitazone metabolite investigation revealed two unpublished metabolites (M-D and M-A). M-A is a hydration product and may be related to the mechanism of ring opening and the toxicity of pioglitazone. The metabolites of GQ-11 are products of oxidation; no ring-opening metabolite was observed for GQ-11. In conclusion, under the same experimental conditions, a ring-opening metabolite was observed only for pioglitazone. The resistance of GQ-11 to the ring opening is probably related to N -substitution in the TZD ring. Copyright © 2018 by The American Society for Pharmacology and Experimental Therapeutics.

  4. Antiviral Activity of Peanut (Arachis hypogaea L.) Skin Extract Against Human Influenza Viruses.

    PubMed

    Makau, Juliann Nzembi; Watanabe, Ken; Mohammed, Magdy M D; Nishida, Noriyuki

    2018-05-30

    The high propensity of influenza viruses to develop resistance to antiviral drugs necessitates the continuing search for new therapeutics. Peanut skins, which are low-value byproducts of the peanut industry, are known to contain high levels of polyphenols. In this study, we investigated the antiviral activity of ethanol extracts of peanut skins against various influenza viruses using cell-based assays. Extracts with a higher polyphenol content exhibited higher antiviral activities, suggesting that the active components are the polyphenols. An extract prepared from roasted peanut skins effectively inhibited the replication of influenza virus A/WSN/33 with a half maximal inhibitory concentration of 1.3 μg/mL. Plaque assay results suggested that the extract inhibits the early replication stages of the influenza virus. It demonstrated activity against both influenza type A and type B viruses. Notably, the extract exhibited a potent activity against a clinical isolate of the 2009 H1N1 pandemic, which had reduced sensitivity to oseltamivir. Moreover, a combination of peanut skin extract with the anti-influenza drugs, oseltamivir and amantadine, synergistically increased their antiviral activity. These data demonstrate the potential application of peanut skin extract in the development of new therapeutic options for influenza management.

  5. Prediction of Losartan-Active Carboxylic Acid Metabolite Exposure Following Losartan Administration Using Static and Physiologically Based Pharmacokinetic Models.

    PubMed

    Nguyen, Hoa Q; Lin, Jian; Kimoto, Emi; Callegari, Ernesto; Tse, Susanna; Obach, R Scott

    2017-09-01

    The aim of this study was to evaluate a strategy based on static and dynamic physiologically based pharmacokinetic (PBPK) modeling for the prediction of metabolite and parent drug area under the time-concentration curve ratio (AUC m /AUC p ) and their PK profiles in humans using in vitro data when active transport processes are involved in disposition. The strategy was applied to losartan and its pharmacologically active metabolite carboxylosartan as test compounds. Hepatobiliary transport including transport-mediated uptake, canilicular and basolateral efflux, and metabolic clearance estimates were obtained from in vitro studies using human liver microsomes and sandwich-cultured hepatocytes. Human renal clearance of carboxylosartan was estimated from dog renal clearance using allometric scaling approach. All clearance mechanisms were mechanistically incorporated in a static model to predict the relative exposure of carboxylosartan versus losartan (AUC m /AUC p ). The predicted AUC m /AUC p were consistent with the observed data following intravenous and oral administration of losartan. Moreover, the in vitro parameters were used as initial parameters in PBPK permeability-limited disposition models to predict the concentration-time profiles for both parent and its active metabolite after oral administration of losartan. The PBPK model was able to recover the plasma profiles of both losartan and carboxylosartan, further substantiating the validity of this approach. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  6. Influence of Different Drying Treatments and Extraction Solvents on the Metabolite Profile and Nitric Oxide Inhibitory Activity of Ajwa Dates.

    PubMed

    Abdul-Hamid, Nur Ashikin; Abas, Faridah; Ismail, Intan Safinar; Shaari, Khozirah; Lajis, Nordin H

    2015-11-01

    This study aimed to examine the variation in the metabolite profiles and nitric oxide (NO) inhibitory activity of Ajwa dates that were subjected to 2 drying treatments and different extraction solvents. (1)H NMR coupled with multivariate data analysis was employed. A Griess assay was used to determine the inhibition of the production of NO in RAW 264.7 cells treated with LPS and interferon-γ. The oven dried (OD) samples demonstrated the absence of asparagine and ascorbic acid as compared to the freeze dried (FD) dates. The principal component analysis showed distinct clusters between the OD and FD dates by the second principal component. In respect of extraction solvents, chloroform extracts can be distinguished by the absence of arginine, glycine and asparagine compared to the methanol and 50% methanol extracts. The chloroform extracts can be clearly distinguished from the methanol and 50% methanol extracts by first principal component. Meanwhile, the loading score plot of partial least squares analysis suggested that beta glucose, alpha glucose, choline, ascorbic acid and glycine were among the metabolites that were contributing to higher biological activity displayed by FD and methanol extracts of Ajwa. The results highlight an alternative method of metabolomics approach for determination of the metabolites that contribute to NO inhibitory activity. The association between metabolite profiles and nitric oxide (NO) inhibitory activity of the various extracts of Ajwa dates was evaluated by utilizing partial least squares (PLS) model. The validated PLS model can be employed to predict the NO inhibitory activity of new samples of date fruits based on their NMR spectra which was important for assessing fruit quality. The information gained might be used as guidance for quality control, nutritional values and as a basis for the preparation of any food supplements for human health that employs date palm fruit as the raw material. © 2015 Institute of Food

  7. Endophytic Streptomyces in the traditional medicinal plant Arnica montana L.: secondary metabolites and biological activity.

    PubMed

    Wardecki, Tina; Brötz, Elke; De Ford, Christian; von Loewenich, Friederike D; Rebets, Yuriy; Tokovenko, Bogdan; Luzhetskyy, Andriy; Merfort, Irmgard

    2015-08-01

    Arnica montana L. is a medical plant of the Asteraceae family and grows preferably on nutrient poor soils in mountainous environments. Such surroundings are known to make plants dependent on symbiosis with other organisms. Up to now only arbuscular mycorrhizal fungi were found to act as endophytic symbiosis partners for A. montana. Here we identified five Streptomyces strains, microorganisms also known to occur as endophytes in plants and to produce a huge variety of active secondary metabolites, as inhabitants of A. montana. The secondary metabolite spectrum of these strains does not contain sesquiterpene lactones, but consists of the glutarimide antibiotics cycloheximide and actiphenol as well as the diketopiperazines cyclo-prolyl-valyl, cyclo-prolyl-isoleucyl, cyclo-prolyl-leucyl and cyclo-prolyl-phenylalanyl. Notably, genome analysis of one strain was performed and indicated a huge genome size with a high number of natural products gene clusters among which genes for cycloheximide production were detected. Only weak activity against the Gram-positive bacterium Staphylococcus aureus was revealed, but the extracts showed a marked cytotoxic activity as well as an antifungal activity against Candida parapsilosis and Fusarium verticillioides. Altogether, our results provide evidence that A. montana and its endophytic Streptomyces benefit from each other by completing their protection against competitors and pathogens and by exchanging plant growth promoting signals with nutrients.

  8. Solving the Jigsaw Puzzle of Wound-Healing Potato Cultivars: Metabolite Profiling and Antioxidant Activity of Polar Extracts

    PubMed Central

    2015-01-01

    Potato (Solanum tuberosum L.) is a worldwide food staple, but substantial waste accompanies the cultivation of this crop due to wounding of the outer skin and subsequent unfavorable healing conditions. Motivated by both economic and nutritional considerations, this metabolite profiling study aims to improve understanding of closing layer and wound periderm formation and guide the development of new methods to ensure faster and more complete healing after skin breakage. The polar metabolites of wound-healing tissues from four potato cultivars with differing patterns of tuber skin russeting (Norkotah Russet, Atlantic, Chipeta, and Yukon Gold) were analyzed at three and seven days after wounding, during suberized closing layer formation and nascent wound periderm development, respectively. The polar extracts were assessed using LC-MS and NMR spectroscopic methods, including multivariate analysis and tentative identification of 22 of the 24 biomarkers that discriminate among the cultivars at a given wound-healing time point or between developmental stages. Differences among the metabolites that could be identified from NMR- and MS-derived biomarkers highlight the strengths and limitations of each method, also demonstrating the complementarity of these approaches in terms of assembling a complete molecular picture of the tissue extracts. Both methods revealed that differences among the cultivar metabolite profiles diminish as healing proceeds during the period following wounding. The biomarkers included polyphenolic amines, flavonoid glycosides, phenolic acids and glycoalkaloids. Because wound healing is associated with oxidative stress, the free radical scavenging activities of the extracts from different cultivars were measured at each wounding time point, revealing significantly higher scavenging activity of the Yukon Gold periderm especially after 7 days of wounding. PMID:24998264

  9. Synthesis and Evaluation of Vitamin D Receptor-Mediated Activities of Cholesterol and Vitamin D Metabolites

    PubMed Central

    Teske, Kelly A.; Bogart, Jonathan W.; Sanchez, Luis M.; Yu, Olivia B.; Preston, Joshua V.; Cook, James M.; Silvaggi, Nicholas R.; Bikle, Daniel D.; Arnold, Leggy A.

    2016-01-01

    A systematic study with phase 1 and phase 2 metabolites of cholesterol and vitamin D was conducted to determine whether their biological activity is mediated by the vitamin D receptor (VDR). The investigation necessitated the development of novel synthetic routes for lithocholic acid (LCA) glucuronides (Gluc). Biochemical and cell-based assays were used to demonstrate that hydroxylated LCA analogs were not able to bind VDR. This excludes VDR from mediating their biological and pharmacological activities. Among the synthesized LCA conjugates a novel VDR agonist was identified. LCA Gluc II increased the expression of CYP24A1 in DU145 cancer cells especially in the presence of the endogenous VDR ligand 1,25(OH)2D3. Furthermore, the methyl ester of LCA was identified as novel VDR antagonist. For the first time, we showed that calcitroic acid, the assumed inactive final metabolite of vitamin D, was able to activate VDR-mediated transcription to a higher magnitude than bile acid LCA. Due to a higher metabolic stability in comparison to vitamin D, a very low toxicity, and high concentration in bile and intestine, calcitroic acid is likely to be an important mediator of the protective vitamin D properties against colon cancer. PMID:26774929

  10. The glycolytic metabolite methylglyoxal activates Pap1 and Sty1 stress responses in Schizosaccharomyces pombe.

    PubMed

    Zuin, Alice; Vivancos, Ana P; Sansó, Miriam; Takatsume, Yoshifumi; Ayté, José; Inoue, Yoshiharu; Hidalgo, Elena

    2005-11-04

    Methylglyoxal, a toxic metabolite synthesized in vivo during glycolysis, inhibits cell growth. One of the mechanisms protecting eukaryotic cells against its toxicity is the glyoxalase system, composed of glyoxalase I and II (glo1 and glo2), which converts methylglyoxal into d-lactic acid in the presence of glutathione. Here we have shown that the two principal oxidative stress response pathways of Schizosaccharomyces pombe, Sty1 and Pap1, are involved in the response to methylglyoxal toxicity. The mitogen-activated protein kinase Sty1 is phosphorylated and accumulates in the nucleus following methylglyoxal treatment. Moreover, glo2 expression is induced by methylglyoxal and environmental stresses in a Sty1-dependent manner. The transcription factor Pap1 also accumulates in the nucleus, activating the expression of its target genes following methylglyoxal treatment. Our studies showed that the C-terminal cysteine-rich domain of Pap1 is sufficient for methylglyoxal sensing. Furthermore, the redox status of Pap1 is not changed by methylglyoxal. We propose that methylglyoxal treatment triggers Pap1 and Sty1 nuclear accumulation, and we describe the molecular basis of such activation mechanisms. In addition, we discuss the potential physiological significance of these responses to a natural toxic metabolite.

  11. Carrier-Mediated Prodrug Uptake to Improve the Oral Bioavailability of Polar Drugs: An Application to an Oseltamivir Analogue

    PubMed Central

    Incecayir, Tuba; Sun, Jing; Tsume, Yasuhiro; Xu, Hao; Gose, Tomoka; Nakanishi, Takeo; Tamai, Ikumi; Hilfinger, John; Lipka, Elke; Amidon, Gordon L.

    2016-01-01

    The goal of this study was to improve the intestinal mucosal cell membrane permeability of the poorly absorbed guanidino analogue of a neuraminidase inhibitor, oseltamivir carboxylate (GOC) using a carrier mediated strategy. Valyl amino acid prodrug of GOC with isopropyl-methylenedioxy linker (GOC-ISP-Val) was evaluated as the potential substrate for intestinal oligopeptide transporter, hPEPT1 in Xenopus laevis oocytes heterologously expressing hPEPT1 and an intestinal mouse perfusion system. The diastereomers of GOC-ISP-Val were assessed for chemical and metabolic stability. Permeability of GOC-ISP-Val was determined in Caco-2 cells and mice. Diastereomer 2 was about two times more stable than diastereomer 1 in simulated intestinal fluid and rapidly hydrolyzed to the parent drug in cell homogenates. The prodrug had a nine times enhanced apparent permeability (Papp) in Caco-2 cells compared to the parent drug. Both diastereomer exhibited high effective permeability (Peff ) in mice, 6.32±3.12 and 5.20±2.81 x10−5 cm/s for diastereomer 1 and 2, respectively. GOC-ISP-Val was found to be a substrate of hPEPT1. Overall, this study indicates that the prodrug, GOC-ISP-Val seems to be a promising oral anti-influenza agent that has sufficient stability at physiologically relevant pHs prior to absorption, significantly improved permeability via hPEPT1 and potentially rapid activation in the intestinal cells. PMID:26869437

  12. Biosynthesis of the active compounds of Isatis indigotica based on transcriptome sequencing and metabolites profiling

    PubMed Central

    2013-01-01

    Backgroud Isatis indigotica is a widely used herb for the clinical treatment of colds, fever, and influenza in Traditional Chinese Medicine (TCM). Various structural classes of compounds have been identified as effective ingredients. However, little is known at genetics level about these active metabolites. In the present study, we performed de novo transcriptome sequencing for the first time to produce a comprehensive dataset of I. indigotica. Results A database of 36,367 unigenes (average length = 1,115.67 bases) was generated by performing transcriptome sequencing. Based on the gene annotation of the transcriptome, 104 unigenes were identified covering most of the catalytic steps in the general biosynthetic pathways of indole, terpenoid, and phenylpropanoid. Subsequently, the organ-specific expression patterns of the genes involved in these pathways, and their responses to methyl jasmonate (MeJA) induction, were investigated. Metabolites profile of effective phenylpropanoid showed accumulation pattern of secondary metabolites were mostly correlated with the transcription of their biosynthetic genes. According to the analysis of UDP-dependent glycosyltransferases (UGT) family, several flavonoids were indicated to exist in I. indigotica and further identified by metabolic profile using UPLC/Q-TOF. Moreover, applying transcriptome co-expression analysis, nine new, putative UGTs were suggested as flavonol glycosyltransferases and lignan glycosyltransferases. Conclusions This database provides a pool of candidate genes involved in biosynthesis of effective metabolites in I. indigotica. Furthermore, the comprehensive analysis and characterization of the significant pathways are expected to give a better insight regarding the diversity of chemical composition, synthetic characteristics, and the regulatory mechanism which operate in this medical herb. PMID:24308360

  13. Chemical and bioactive diversities of the genus Chaetomium secondary metabolites.

    PubMed

    Zhang, Q; Li, H-Q; Zong, S-C; Gao, J-M; Zhang, A-L

    2012-02-01

    The genus Chaetomium fungi are considered to be a rich source of novel and bioactive secondary metabolites of great importance. Up till now, a variety of more than 200 secondary metabolites belonging to diverse structural types of chaetoglobosins, epipolythiodioxopiperazines, azaphilones, xanthones, anthraquinones, chromones, depsidones, terpenoids, and steroids have been discovered. Most of these fungal metabolites exhibited antitumor, cytotoxic, antimalarial, enzyme inhibitory, antibiotic, and other activities. This review covers the extraction, structure elucidation, structural diversity, and biological activities of natural products isolated from about 30 fungi associated with marine- and terrestrial- origins, and highlights some bioactive compounds as well as their mechanisms of action and structure-activity relationships.

  14. Anthocyanins and their gut metabolites reduce the adhesion of monocyte to TNFα-activated endothelial cells at physiologically relevant concentrations.

    PubMed

    Krga, Irena; Monfoulet, Laurent-Emmanuel; Konic-Ristic, Aleksandra; Mercier, Sylvie; Glibetic, Maria; Morand, Christine; Milenkovic, Dragan

    2016-06-01

    An increasing number of evidence suggests a protective role of dietary anthocyanins against cardiovascular diseases. Anthocyanins' extensive metabolism indicates that their metabolites could be responsible for the protective effects associated with consumption of anthocyanin-rich foods. The aim of this work was to investigate the effect of plasma anthocyanins and their metabolites on the adhesion of monocytes to TNFα-activated endothelial cells and on the expression of genes encoding cell adhesion molecules. Human umbilical vein endothelial cells (HUVECs) were exposed to circulating anthocyanins: cyanidin-3-arabinoside, cyanidin-3-galactoside, cyanidin-3-glucoside, delphinidin-3-glucoside, peonidin-3-glucoside, anthocyanin degradation product: 4-hydroxybenzaldehyde, or to their gut metabolites: protocatechuic, vanillic, ferulic and hippuric acid, at physiologically-relevant concentrations (0.1-2 μM) and time of exposure. Both anthocyanins and gut metabolites decreased the adhesion of monocytes to HUVECs, with a magnitude ranging from 18.1% to 47%. The mixture of anthocyanins and that of gut metabolites also reduced monocyte adhesion. However, no significant effect on the expression of genes encoding E-selectin, ICAM1 and VCAM1 was observed, suggesting that other molecular targets are involved in the observed effect. In conclusion, this study showed the potency of anthocyanins and their gut metabolites to modulate the adhesion of monocytes to endothelial cells, the initial step in atherosclerosis development, under physiologically-relevant conditions. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Combined mass spectrometry-based metabolite profiling of different pigmented rice (Oryza sativa L.) seeds and correlation with antioxidant activities.

    PubMed

    Kim, Ga Ryun; Jung, Eun Sung; Lee, Sarah; Lim, Sun-Hyung; Ha, Sun-Hwa; Lee, Choong Hwan

    2014-09-29

    Nine varieties of pigmented rice (Oryza sativa L.) seeds that were black, red, or white were used to perform metabolite profiling by using ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF-MS) and gas chromatography (GC) TOF-MS, to measure antioxidant activities. Clear grouping patterns determined by the color of the rice seeds were identified in principle component analysis (PCA) derived from UPLC-Q-TOF-MS. Cyanidin-3-glucoside, peonidin-3-glucoside, proanthocyanidin dimer, proanthocyanidin trimer, apigenin-6-C-glugosyl-8-C-arabiboside, tricin-O-rhamnoside-O-hexoside, and lipids were identified as significantly different secondary metabolites. In PCA score plots derived from GC-TOF-MS, Jakwangdo (JKD) and Ilpoom (IP) species were discriminated from the other rice seeds by PC1 and PC2. Valine, phenylalanine, adenosine, pyruvate, nicotinic acid, succinic acid, maleic acid, malonic acid, gluconic acid, xylose, fructose, glucose, maltose, and myo-inositol were significantly different primary metabolites in JKD species, while GABA, asparagine, xylitol, and sucrose were significantly distributed in IP species. Analysis of antioxidant activities revealed that black and red rice seeds had higher activity than white rice seeds. Cyanidin-3-glucoside, peonidin-3-glucoside, proanthocyanidin dimers, proanthocyanidin trimers, and catechin were highly correlated with antioxidant activities, and were more plentiful in black and red rice seeds. These results are expected to provide valuable information that could help improve and develop rice-breeding techniques.

  16. Hypouricaemic action of mangiferin results from metabolite norathyriol via inhibiting xanthine oxidase activity.

    PubMed

    Niu, Yanfen; Liu, Jia; Liu, Hai-Yang; Gao, Li-Hui; Feng, Guo-Hua; Liu, Xu; Li, Ling

    2016-09-01

    Context Mangiferin has been reported to possess a potential hypouricaemic effect. However, the pharmacokinetic studies in rats showed that its oral bioavailability was only 1.2%, suggesting that mangiferin metabolites might exert the action. Objective The hypouricaemic effect and the xanthine oxidase inhibition of mangiferin and norathyriol, a mangiferin metabolite, were investigated. Inhibition of norathyriol analogues (compounds 3-9) toward xanthine oxidase was also evaluated. Materials and methods For a dose-dependent study, mangiferin (1.5-6.0 mg/kg) and norathyriol (0.92-3.7 mg/kg) were administered intragastrically to mice twice daily for five times. For a time-course study, mice received mangiferin and norathyriol both at a single dose of 7.1 μmol/kg. In vitro, inhibition of test compounds (2.4-2.4 mM) against xanthine oxidase activity was evaluated by the spectrophotometrical method. The inhibition type was identified from Lineweaver-Burk plots. Results Norathyriol (0.92, 1.85 and 3.7 mg/kg) dose dependently decreased the serum urate levels by 27.0, 33.6 and 37.4%, respectively. The action was more potent than that of mangiferin at the low dose, but was equivalent at the higher doses. Additionally, the hypouricaemic action of them exhibited a time dependence. In vitro, norathyriol markedly inhibited the xanthine oxidase activities, with the IC50 value of 44.6 μM, but mangiferin did not. The kinetic studies showed that norathyriol was an uncompetitive inhibitor by Lineweaver-Burk plots. The structure-activity relationships exhibited that three hydroxyl groups in norathyriol at the C-1, C-3 and C-6 positions were essential for maintaining xanthine oxidase inhibition. Discussion and conclusion Norathyriol was responsible for the hypouricaemic effect of mangiferin via inhibiting xanthine oxidase activity.

  17. Secondary metabolites of cyanobacteria Nostoc sp.

    NASA Astrophysics Data System (ADS)

    Kobayashi, Akio; Kajiyama, Shin-Ichiro

    1998-03-01

    Cyanobacteria attracted much attention recently because of their secondary metabolites with potent biological activities and unusual structures. This paper reviews some recent studies on the isolation, structural, elucidation and biological activities of the bioactive compounds from cyanobacteria Nostoc species.

  18. Antifungal activity of secondary plant metabolites from potatoes (Solanum tuberosum L.): Glycoalkaloids and phenolic acids show synergistic effects.

    PubMed

    Sánchez-Maldonado, A F; Schieber, A; Gänzle, M G

    2016-04-01

    To study the antifungal effects of the potato secondary metabolites α-solanine, α-chaconine, solanidine and caffeic acid, alone or combined. Resistance to glycoalkaloids varied among the fungal species tested, as derived from minimum inhibitory concentrations assays. Synergistic antifungal activity between glycoalkaloids and phenolic compounds was found. Changes in the fluidity of fungal membranes caused by potato secondary plant metabolites were determined by calculation of the generalized polarization values. The results partially explained the synergistic effect between caffeic acid and α-chaconine and supported findings on membrane disruption mechanisms from previous studies on artificial membranes. LC/MS analysis was used to determine variability and relative amounts of sterols in the different fungal species. Results suggested that the sterol pattern of fungi is related to their resistance to potato glycoalkaloids and to their taxonomy. Fungal resistance to α-chaconine and possibly other glycoalkaloids is species dependent. α-Chaconine and caffeic acid show synergistic antifungal activity. The taxonomic classification and the sterol pattern play a role in fungal resistance to glycoalkaloids. Results improve the understanding of the antifungal mode of action of potato secondary metabolites, which is essential for their potential utilization as antifungal agents in nonfood systems. © 2016 The Society for Applied Microbiology.

  19. [Synthetic biology toward microbial secondary metabolites and pharmaceuticals].

    PubMed

    Wu, Lin-Zhuan; Hong, Bin

    2013-02-01

    Microbial secondary metabolites are one of the major sources of anti-bacterial, anti-fungal, antitumor, anti-virus and immunosuppressive agents for clinical use. Present challenges in microbial pharmaceutical development are the discovery of novel secondary metabolites with significant biological activities, improving the fermentation titers of industrial microbial strains, and production of natural product drugs by re-establishing their biosynthetic pathways in suitable microbial hosts. Synthetic biology, which is developed from systematic biology and metabolic engineering, provides a significant driving force for microbial pharmaceutical development. The review describes the major applications of synthetic biology in novel microbial secondary metabolite discovery, improved production of known secondary metabolites and the production of some natural drugs in genetically modified or reconstructed model microorganisms.

  20. Ruta graveolens Extracts and Metabolites against Spodoptera frugiperda.

    PubMed

    Ayil-Gutiérrez, Benjamin A; Villegas-Mendoza, Jesús M; Santes-Hernndez, Zuridai; Paz-González, Alma D; Mireles-Martínez, Maribel; Rosas-García, Ninfa M; Rivera, Gildardo

    2015-11-01

    The biological activity of Ruta graveolens leaf tissue extracts obtained with different solvents (ethyl acetate, ethanol, and water) and metabolites (psoralen, 2- undecanone and rutin) against Spodoptera frugiperda was evaluated. Metabolites levels in extracts were quantified by HPLC and GC. Ethyl acetate and ethanol extracts showed 94% and 78% mortality, respectively. Additionally, psoralen metabolite showed a high mortality as cypermethrin. Metabolite quantification in extracts shows the presence of 2-undecanone (87.9 µmoles mg(-1) DW), psoralen (3.6 µmoles mg(-1) DW) and rutin (0.001 pmoles mg(-1) DW). We suggest that these concentrations of 2-undecanone and psoralen in R. graveolens leaf tissue extracts could be responsible for S. frugiperda mortality.

  1. Network Analysis of Enzyme Activities and Metabolite Levels and Their Relationship to Biomass in a Large Panel of Arabidopsis Accessions[C][W][OA

    PubMed Central

    Sulpice, Ronan; Trenkamp, Sandra; Steinfath, Matthias; Usadel, Bjorn; Gibon, Yves; Witucka-Wall, Hanna; Pyl, Eva-Theresa; Tschoep, Hendrik; Steinhauser, Marie Caroline; Guenther, Manuela; Hoehne, Melanie; Rohwer, Johann M.; Altmann, Thomas; Fernie, Alisdair R.; Stitt, Mark

    2010-01-01

    Natural genetic diversity provides a powerful resource to investigate how networks respond to multiple simultaneous changes. In this work, we profile maximum catalytic activities of 37 enzymes from central metabolism and generate a matrix to investigate species-wide connectivity between metabolites, enzymes, and biomass. Most enzyme activities change in a highly coordinated manner, especially those in the Calvin-Benson cycle. Metabolites show coordinated changes in defined sectors of metabolism. Little connectivity was observed between maximum enzyme activities and metabolites, even after applying multivariate analysis methods. Measurements of posttranscriptional regulation will be required to relate these two functional levels. Individual enzyme activities correlate only weakly with biomass. However, when they are used to estimate protein abundances, and the latter are summed and expressed as a fraction of total protein, a significant positive correlation to biomass is observed. The correlation is additive to that obtained between starch and biomass. Thus, biomass is predicted by two independent integrative metabolic biomarkers: preferential investment in photosynthetic machinery and optimization of carbon use. PMID:20699391

  2. Metabolomics and Cheminformatics Analysis of Antifungal Function of Plant Metabolites

    PubMed Central

    Cuperlovic-Culf, Miroslava; Rajagopalan, NandhaKishore; Tulpan, Dan; Loewen, Michele C.

    2016-01-01

    Fusarium head blight (FHB), primarily caused by Fusarium graminearum, is a devastating disease of wheat. Partial resistance to FHB of several wheat cultivars includes specific metabolic responses to inoculation. Previously published studies have determined major metabolic changes induced by pathogens in resistant and susceptible plants. Functionality of the majority of these metabolites in resistance remains unknown. In this work we have made a compilation of all metabolites determined as selectively accumulated following FHB inoculation in resistant plants. Characteristics, as well as possible functions and targets of these metabolites, are investigated using cheminformatics approaches with focus on the likelihood of these metabolites acting as drug-like molecules against fungal pathogens. Results of computational analyses of binding properties of several representative metabolites to homology models of fungal proteins are presented. Theoretical analysis highlights the possibility for strong inhibitory activity of several metabolites against some major proteins in Fusarium graminearum, such as carbonic anhydrases and cytochrome P450s. Activity of several of these compounds has been experimentally confirmed in fungal growth inhibition assays. Analysis of anti-fungal properties of plant metabolites can lead to the development of more resistant wheat varieties while showing novel application of cheminformatics approaches in the analysis of plant/pathogen interactions. PMID:27706030

  3. Influence of Sulforaphane Metabolites on Activities of Human Drug-Metabolizing Cytochrome P450 and Determination of Sulforaphane in Human Liver Cells.

    PubMed

    Vanduchova, Alena; Tomankova, Veronika; Anzenbacher, Pavel; Anzenbacherova, Eva

    2016-12-01

    The influence of metabolites of sulforaphane, natural compounds present in broccoli (Brassica oleracea var. botrytis italica) and in other cruciferous vegetables, on drug-metabolizing cytochrome P450 (CYP) enzymes in human liver microsomes and possible entry of sulforaphane into human hepatic cells were investigated. Metabolites studied are compounds derived from sulforaphane by the mercapturic acid pathway (conjugation with glutathione and by following reactions), namely sulforaphane glutathione and sulforaphane cysteine conjugates and sulforaphane-N-acetylcysteine. Their possible effect on four drug-metabolizing CYP enzymes, CYP3A4 (midazolam 1'-hydroxylation), CYP2D6 (bufuralol 1'-hydroxylation), CYP1A2 (7-ethoxyresorufin O-deethylation), and CYP2B6 (7-ethoxy-4-(trifluoromethyl)coumarin O-deethylation), was tested. Inhibition of four prototypical CYP activities by sulforaphane metabolites was studied in pooled human liver microsomes. Sulforaphane metabolites did not considerably affect biological function of drug-metabolizing CYPs in human liver microsomes except for CYP2D6, which was found to be inhibited down to 73-78% of the original activity. Analysis of the entry of sulforaphane into human hepatocytes was done by cell disruption by sonication, methylene chloride extraction, and modified high-performance liquid chromatography method. The results have shown penetration of sulforaphane into the human hepatic cells.

  4. Biotransformation of dianabol with the filamentous fungi and β-glucuronidase inhibitory activity of resulting metabolites.

    PubMed

    Khan, Naik T; Zafar, Salman; Noreen, Shagufta; Al Majid, Abdullah M; Al Othman, Zeid A; Al-Resayes, Saud Ibrahim; Atta-ur-Rahman; Choudhary, M Iqbal

    2014-07-01

    Biotransformation of the anabolic steroid dianabol (1) by suspended-cell cultures of the filamentous fungi Cunninghamella elegans and Macrophomina phaseolina was studied. Incubation of 1 with C. elegans yielded five hydroxylated metabolites 2-6, while M. phaseolina transformed compound 1 into polar metabolites 7-11. These metabolites were identified as 6β,17β-dihydroxy-17α-methylandrost-1,4-dien-3-one (2), 15α,17β-dihydroxy-17α-methylandrost-1,4-dien-3-one (3), 11α,17β-dihydroxy-17α-methylandrost-1,4-dien-3-one (4), 6β,12β,17β-trihydroxy-17α-methylandrost-1,4-dien-3-one (5), 6β,15α,17β-trihydroxy-17α-methylandrost-1,4-dien-3-one (6), 17β-hydroxy-17α-methylandrost-1,4-dien-3,6-dione (7), 7β,17β,-dihydroxy-17α-methylandrost-1,4-dien-3-one (8), 15β,17β-dihydroxy-17α-methylandrost-1,4-dien-3-one (9), 17β-hydroxy-17α-methylandrost-1,4-dien-3,11-dione (10), and 11β,17β-dihydroxy-17α-methylandrost-1,4-dien-3-one (11). Metabolite 3 was also transformed chemically into diketone 12 and oximes 13, and 14. Compounds 6 and 12-14 were identified as new derivatives of dianabol (1). The structures of all transformed products were deduced on the basis of spectral analyses. Compounds 1-14 were evaluated for β-glucuronidase enzyme inhibitory activity. Compounds 7, 13, and 14 showed a strong inhibition of β-glucuronidase enzyme, with IC50 values between 49.0 and 84.9 μM. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Urinary metabolites of isorhynchophylline in rats and their neuroprotective activities in the HT22 cell assay

    PubMed Central

    Chen, Fangfang; Qi, Wen; Sun, Jiahong; Simpkins, James W.; Yuan, Dan

    2015-01-01

    Isorhynchophylline is one of the major alkaloids from the Uncaria hook possessing the effects of lowered blood pressure, vasodilatation and protection against ischemia-induced neuronal damage. However, the metabolic pathway of isorhynchophylline has not been fully reported yet. In this paper, the metabolism of isorhynchophylline was investigated in rats. Five metabolites were isolated by using solvent extraction and repeated chromatographic methods, and identified by spectroscopic methods including UV, MS, NMR and CD experiments. Three new compounds were identified as 5-oxoisorhynchophyllic acid-22-O-β-D-glucuronide (M1), 17-O-demethyl-16,17-dihydro isorhynchophylline (M2) and 5-oxoisorhynchophyllic acid (M4) together with two known compounds isorhynchophylline (M0) and rhynchophylline (M3). Possible metabolic pathways of isorhynchophylline are proposed. Furthermore, the activity assay for all the metabolites showed that isorhynchophylline (M0) exhibited potent neuroprotective effects against glutamate-induced HT22 cell death. However, little or weak neuroprotective activities were observed for M1–M4. Our present study is important to further understand its metabolic fate and disposition in humans. PMID:24910000

  6. An invasive plant promotes its arbuscular mycorrhizal symbioses and competitiveness through its secondary metabolites: indirect evidence from activated carbon.

    PubMed

    Yuan, Yongge; Tang, Jianjun; Leng, Dong; Hu, Shuijin; Yong, Jean W H; Chen, Xin

    2014-01-01

    Secondary metabolites released by invasive plants can increase their competitive ability by affecting native plants, herbivores, and pathogens at the invaded land. Whether these secondary metabolites affect the invasive plant itself, directly or indirectly through microorganisms, however, has not been well documented. Here we tested whether activated carbon (AC), a well-known absorbent for secondary metabolites, affect arbuscular mycorrhizal (AM) symbioses and competitive ability in an invasive plant. We conducted three experiments (experiments 1-3) with the invasive forb Solidago canadensis and the native Kummerowia striata. Experiment 1 determined whether AC altered soil properties, levels of the main secondary metabolites in the soil, plant growth, and AMF communities associated with S. canadensis and K. striata. Experiment 2 determined whether AC affected colonization of S. canadensis by five AMF, which were added to sterilized soil. Experiment 3 determined the competitive ability of S. canadensis in the presence and absence of AMF and AC. In experiment 1, AC greatly decreased the concentrations of the main secondary metabolites in soil, and the changes in concentrations were closely related with the changes of AMF in S. canadensis roots. In experiment 2, AC inhibited the AMF Glomus versiforme and G. geosporum but promoted G. mosseae and G. diaphanum in the soil and also in S. canadensis roots. In experiment 3, AC reduced S. canadensis competitive ability in the presence but not in the absence of AMF. Our results provided indirect evidence that the secondary metabolites (which can be absorbed by AC) of the invasive plant S. canadensis may promote S. canadensis competitiveness by enhancing its own AMF symbionts.

  7. Modulation of antimicrobial metabolites production by the fungus Aspergillus parasiticus

    PubMed Central

    Bracarense, Adriana A.P.; Takahashi, Jacqueline A.

    2014-01-01

    Biosynthesis of active secondary metabolites by fungi occurs as a specific response to the different growing environments. Changes in this environment alter the chemical and biological profiles leading to metabolites diversification and consequently to novel pharmacological applications. In this work, it was studied the influence of three parameters (fermentation length, medium composition and aeration) in the biosyntheses of antimicrobial metabolites by the fungus Aspergillus parasiticus in 10 distinct fermentation periods. Metabolism modulation in two culturing media, CYA and YES was evaluated by a 22 full factorial planning (ANOVA) and on a 23 factorial planning, role of aeration, medium composition and carbohydrate concentration were also evaluated. In overall, 120 different extracts were prepared, their HPLC profiles were obtained and the antimicrobial activity against A. flavus, C. albicans, E. coli and S. aureus of all extracts was evaluated by microdilution bioassay. Yield of kojic acid, a fine chemical produced by the fungus A. parasiticus was determined in all extracts. Statistical analyses pointed thirteen conditions able to modulate the production of bioactive metabolites by A. parasiticus. Effect of carbon source in metabolites diversification was significant as shown by the changes in the HPLC profiles of the extracts. Most of the extracts presented inhibition rates higher than that of kojic acid as for the extract obtained after 6 days of fermentation in YES medium under stirring. Kojic acid was not the only metabolite responsible for the activity since some highly active extracts showed to possess low amounts of this compound, as determined by HPLC. PMID:24948950

  8. Activation of dormant secondary metabolite production by introducing neomycin resistance into the deep-sea fungus, Aspergillus versicolor ZBY-3.

    PubMed

    Dong, Yuan; Cui, Cheng-Bin; Li, Chang-Wei; Hua, Wei; Wu, Chang-Jing; Zhu, Tian-Jiao; Gu, Qian-Qun

    2014-07-29

    A new ultrasound-mediated approach has been developed to introduce neomycin-resistance to activate silent pathways for secondary metabolite production in a bio-inactive, deep-sea fungus, Aspergillus versicolor ZBY-3. Upon treatment of the ZBY-3 spores with a high concentration of neomycin by proper ultrasound irradiation, a total of 30 mutants were obtained by single colony isolation. The acquired resistance of the mutants to neomycin was confirmed by a resistance test. In contrast to the ZBY-3 strain, the EtOAc extracts of 22 of the 30 mutants inhibited the human cancer K562 cells, indicating that these mutants acquired a capability to produce antitumor metabolites. HPLC-photodiode array detector (PDAD)-UV and HPLC-electron spray ionization (ESI)-MS analyses of the EtOAc extracts of seven bioactive mutants and the ZBY-3 strain indicated that diverse secondary metabolites have been newly produced in the mutant extracts in contrast to the ZBY-3 extract. The followed isolation and characterization demonstrated that six metabolites, cyclo(D-Pro-D-Phe) (1), cyclo(D-Tyr-D-Pro) (2), phenethyl 5-oxo-L-prolinate (3), cyclo(L-Ile-L-Pro) (4), cyclo(L-Leu-L-Pro) (5) and 3β,5α,9α-trihydroxy-(22E,24R)-ergosta-7,22-dien-6-one (6), were newly produced by the mutant u2n2h3-3 compared to the parent ZBY-3 strain. Compound 3 was a new compound; 2 was isolated from a natural source for the first time, and all of these compounds were also not yet found in the metabolites of other A. versicolor strains. Compounds 1-6 inhibited the K562 cells, with inhibition rates of 54.6% (1), 72.9% (2), 23.5% (3), 29.6% (4), 30.9% (5) and 51.1% (6) at 100 μg/mL, and inhibited also other human cancer HL-60, BGC-823 and HeLa cells, to some extent. The present study demonstrated the effectiveness of the ultrasound-mediated approach to activate silent metabolite production in fungi by introducing acquired resistance to aminoglycosides and its potential for discovering new compounds from silent fungal

  9. Barks Essential Oil, Secondary Metabolites and Biological Activities of Four Organs of Tunisian Calligonum azel Maire.

    PubMed

    Bannour, Marwa; Aouadhi, Chedia; Khalfaoui, Houssem; Aschi-Smiti, Samira; Khadhri, Ayda

    2016-11-01

    This study is the first to investigate the chemical composition of barks essential oil (EO), secondary metabolites and biological activities of the MeOH and infusions extracts of seeds, leaves, barks and roots of Calligonum azel Maire (Polygonaceae) harvested from Tunisian desert. The gas chromatography/mass spectrometry (GC/MS) results showed the presence of fifty-four compounds in barks EO. The major components were: viridiflorol (14.6%), α-eudesmol (8.65%), trans-caryophyllene (6.72%), elemol (6.63%), β-eudesmol (6.21%). The obtained results showed that C. azel is a very rich plant in secondary metabolites. High contents in polyphenols, flavonoids and tannins were observed in both extracts of all studied organs. Significant differences were found between both extracts of the four organs. Thus, polyphenols and tannins were more abundant in leaves infusion extract, while, flavonoids showed a high level in barks extract. The antioxidant activity data demonstrated that all extracts showed strong antioxidant and radical scavenging activities. The MeOH extracts presented potential for antibacterial and antifungal activities against all tested microorganisms. The inhibition zones diameters and minimal inhibitrice concentration values were in the range of 9 - 15 mm and 2.5 - 20 μg/ml, respectively. This study demonstrated that C. azel can be regarded as an excellent plant source for natural antimicrobial agents. © 2016 Wiley-VHCA AG, Zurich, Switzerland.

  10. Antioxidative properties of functional polyphenols and their metabolites assessed by an ORAC assay.

    PubMed

    Ishimoto, Hidekazu; Tai, Akihiro; Yoshimura, Morio; Amakura, Yoshiaki; Yoshida, Takashi; Hatano, Tsutomu; Ito, Hideyuki

    2012-01-01

    We compared the antioxidative activities of polyphenol metabolites with those of intact functional polyphenols by an assay of the oxygen radical absorbance capacity (ORAC). The metabolites of ellagitannin geraniin, chlorogenic acid, and (-)-epigallocatechin gallate displayed more potent antioxidative activity than their respective original compounds. Our findings suggest that these metabolites may play important roles as biological antioxidants after their consumption.

  11. Anticancer Activities of Protopanaxadiol- and Protopanaxatriol-Type Ginsenosides and Their Metabolites

    PubMed Central

    Chen, Xiao-Jia; Zhang, Xiao-Jing; Shui, Yan-Mei; Wan, Jian-Bo

    2016-01-01

    Recently, most anticancer drugs are derived from natural resources such as marine, microbial, and botanical sources, but the low success rates of chemotherapies and the development of multidrug resistance emphasize the importance of discovering new compounds that are both safe and effective against cancer. Ginseng types, including Asian ginseng, American ginseng, and notoginseng, have been used traditionally to treat various diseases, due to their immunomodulatory, neuroprotective, antioxidative, and antitumor activities. Accumulating reports have shown that ginsenosides, the major active component of ginseng, were helpful for tumor treatment. 20(S)-Protopanaxadiol (PDS) and 20(S)-protopanaxatriol saponins (PTS) are two characteristic types of triterpenoid saponins in ginsenosides. PTS holds capacity to interfere with crucial metabolism, while PDS could affect cell cycle distribution and prodeath signaling. This review aims at providing an overview of PTS and PDS, as well as their metabolites, regarding their different anticancer effects with the proposal that these compounds might be potent additions to the current chemotherapeutic strategy against cancer. PMID:27446225

  12. Thiopurine methyltransferase genotype–phenotype discordance and thiopurine active metabolite formation in childhood acute lymphoblastic leukaemia

    PubMed Central

    Lennard, Lynne; Cartwright, Cher Suzanne; Wade, Rachel; Richards, Susan M; Vora, Ajay

    2013-01-01

    Aims In children with acute lymphoblastic leukaemia (ALL) bone marrow activity can influence red blood cell (RBC) kinetics, the surrogate tissue for thiopurine methyltransferase (TPMT) measurements. The aim of this study was to investigate TPMT phenotype–genotype concordance in ALL, and the influence of TPMT on thiopurine metabolite formation. Methods We measured TPMT (activity, as units ml−1 packed RBCs and genotype) at diagnosis (n = 1150) and TPMT and thioguanine nucleotide (TGN) and methylmercaptopurine nucleotide (MeMPN) metabolites (pmol/8 × 108 RBCs) during chemotherapy (n = 1131) in children randomized to thioguanine or mercaptopurine on the United Kingdom trial ALL97. Results Median TPMT activity at diagnosis (8.5 units) was significantly lower than during chemotherapy (13.8 units, median difference 5.1 units, 95% confidence interval (CI) 4.8, 5.4, P < 0.0001). At diagnosis genotype–phenotype was discordant. During chemotherapy the overall concordance was 92%, but this fell to 55% in the intermediate activity cohort (45% had wild-type genotypes). For both thiopurines TGN concentrations differed by TPMT status. For mercaptopurine, median TGNs were higher in TPMT heterozygous genotype (754 pmol) than wild-type (360 pmol) patients (median difference 406 pmol, 95% CI 332, 478, P < 0.0001), whilst median MeMPNs, products of the TPMT reaction, were higher in wild-type (10 650 pmol) than heterozygous patients (3868 pmol) (P < 0.0001). In TPMT intermediate activity patients with a wild-type genotype, TGN (median 366 pmol) and MeMPN (median 8590 pmol) concentrations were similar to those in wild-type, high activity patients. Conclusions In childhood ALL, TPMT activity should not be used to predict heterozygosity particularly in blood samples obtained at disease diagnosis. Genotype is a better predictor of TGN accumulation during chemotherapy. PMID:23252716

  13. Thiopurine methyltransferase genotype-phenotype discordance and thiopurine active metabolite formation in childhood acute lymphoblastic leukaemia.

    PubMed

    Lennard, Lynne; Cartwright, Cher Suzanne; Wade, Rachel; Richards, Susan M; Vora, Ajay

    2013-07-01

    In children with acute lymphoblastic leukaemia (ALL) bone marrow activity can influence red blood cell (RBC) kinetics, the surrogate tissue for thiopurine methyltransferase (TPMT) measurements. The aim of this study was to investigate TPMT phenotype-genotype concordance in ALL, and the influence of TPMT on thiopurine metabolite formation. We measured TPMT (activity, as units ml(-1) packed RBCs and genotype) at diagnosis (n = 1150) and TPMT and thioguanine nucleotide (TGN) and methylmercaptopurine nucleotide (MeMPN) metabolites (pmol/8 × 10(8) RBCs) during chemotherapy (n = 1131) in children randomized to thioguanine or mercaptopurine on the United Kingdom trial ALL97. Median TPMT activity at diagnosis (8.5 units) was significantly lower than during chemotherapy (13.8 units, median difference 5.1 units, 95% confidence interval (CI) 4.8, 5.4, P < 0.0001). At diagnosis genotype-phenotype was discordant. During chemotherapy the overall concordance was 92%, but this fell to 55% in the intermediate activity cohort (45% had wild-type genotypes). For both thiopurines TGN concentrations differed by TPMT status. For mercaptopurine, median TGNs were higher in TPMT heterozygous genotype (754 pmol) than wild-type (360 pmol) patients (median difference 406 pmol, 95% CI 332, 478, P < 0.0001), whilst median MeMPNs, products of the TPMT reaction, were higher in wild-type (10 650 pmol) than heterozygous patients (3868 pmol) (P < 0.0001). In TPMT intermediate activity patients with a wild-type genotype, TGN (median 366 pmol) and MeMPN (median 8590 pmol) concentrations were similar to those in wild-type, high activity patients. In childhood ALL, TPMT activity should not be used to predict heterozygosity particularly in blood samples obtained at disease diagnosis. Genotype is a better predictor of TGN accumulation during chemotherapy. © 2012 The Authors. British Journal of Clinical Pharmacology © 2012 The British Pharmacological Society.

  14. Antimicrobial activity of secondary metabolites from Streptomyces sp. K15, an endophyte in Houttuynia cordata Thunb.

    PubMed

    Chen, Huabao; Yang, Chunping; Ke, Tao; Zhou, Miaomiao; Li, Zhaojun; Zhang, Min; Gong, Guoshu; Hou, Taiping

    2015-01-01

    We isolated Streptomyces sp. K15 from the root tissue of Houttuynia cordata Thunb and found that some of its secondary metabolites exhibited significant antimicrobial activity against Botrytis cinerea. Moreover, we separated, purified and identified the major active ingredient to be 2-pyrrol formic acid by using silica gel column chromatography, high-performance liquid chromatography and NMR analysis of the spectral data. 2-Pyrrol formic acid critically inhibited the growth of some phytopathogenic bacteria. Therefore, it has potential value in agricultural applications.

  15. Effects of selexipag and its active metabolite in contrasting the profibrotic myofibroblast activity in cultured scleroderma skin fibroblasts.

    PubMed

    Cutolo, Maurizio; Ruaro, Barbara; Montagna, Paola; Brizzolara, Renata; Stratta, Emanuela; Trombetta, Amelia Chiara; Scabini, Stefano; Tavilla, Pier Paolo; Parodi, Aurora; Corallo, Claudio; Giordano, Nicola; Paolino, Sabrina; Pizzorni, Carmen; Sulli, Alberto; Smith, Vanessa; Soldano, Stefano

    2018-05-02

    Myofibroblasts contribute to fibrosis through the overproduction of extracellular matrix (ECM) proteins, primarily type I collagen (COL-1) and fibronectin (FN), a process which is mediated in systemic sclerosis (SSc) by the activation of fibrogenic intracellular signaling transduction molecules, including extracellular signal-regulated kinases 1 and 2 (Erk1/2) and protein kinase B (Akt). Selexipag is a prostacyclin receptor agonist synthesized for the treatment of pulmonary arterial hypertension. The study investigated the possibility for selexipag and its active metabolite (ACT-333679) to downregulate the profibrotic activity in primary cultures of SSc fibroblasts/myofibroblasts and the fibrogenic signaling molecules involved. Fibroblasts from skin biopsies obtained with Ethics Committee (EC) approval from patients with SSc, after giving signed informed consent, were cultured until the 3 rd culture passage and then either maintained in normal growth medium (untreated cells) or independently treated with different concentrations of selexipag (from 30 μM to 0.3 μM) or ACT-333679 (from 10 μM to 0.1 μM) for 48 h. Protein and gene expressions of α-smooth muscle actin (α-SMA), fibroblast specific protein-1 (S100A4), COL-1, and FN were investigated by western blotting and quantitative real-time PCR. Erk1/2 and Akt phosphorylation was investigated in untreated and ACT-333679-treated cells by western botting. Selexipag and ACT-333679 significantly reduced protein synthesis and gene expression of α-SMA, S100A4, and COL-1 in cultured SSc fibroblasts/myofibroblasts compared to untreated cells, whereas FN was significantly downregulated at the protein level. Interestingly, ACT-333679 significantly reduced the phosphorylation of Erk1/2 and Akt in cultured SSc fibroblasts/myofibroblasts. Selexipag and mainly its active metabolite ACT-333679 were found for the first time to potentially interfere with the profibrotic activity of cultured SSc fibroblasts

  16. The nuclear receptor PPARγ individually responds to serotonin- and fatty acid-metabolites

    PubMed Central

    Waku, Tsuyoshi; Shiraki, Takuma; Oyama, Takuji; Maebara, Kanako; Nakamori, Rinna; Morikawa, Kosuke

    2010-01-01

    The nuclear receptor, peroxisome proliferator-activated receptor γ (PPARγ), recognizes various synthetic and endogenous ligands by the ligand-binding domain. Fatty-acid metabolites reportedly activate PPARγ through conformational changes of the Ω loop. Here, we report that serotonin metabolites act as endogenous agonists for PPARγ to regulate macrophage function and adipogenesis by directly binding to helix H12. A cyclooxygenase inhibitor, indomethacin, is a mimetic agonist of these metabolites. Crystallographic analyses revealed that an indole acetate functions as a common moiety for the recognition by the sub-pocket near helix H12. Intriguingly, a serotonin metabolite and a fatty-acid metabolite each bind to distinct sub-pockets, and the PPARγ antagonist, T0070907, blocked the fatty-acid agonism, but not that of the serotonin metabolites. Mutational analyses on receptor-mediated transcription and coactivator binding revealed that each metabolite individually uses coregulator and/or heterodimer interfaces in a ligand-type-specific manner. Furthermore, the inhibition of the serotonin metabolism reduced the expression of the endogenous PPARγ-target gene. Collectively, these results suggest a novel agonism, in which PPARγ functions as a multiple sensor in response to distinct metabolites. PMID:20717101

  17. Antioxidant Enzyme Activities and Secondary Metabolite Profiling of Oil Palm Seedlings Treated with Combination of NPK Fertilizers Infected with Ganoderma boninense.

    PubMed

    Sahebi, Mahbod; Hanafi, Mohamed M; Mohidin, Hasmah; Rafii, M Y; Azizi, Parisa; Idris, Abu Seman; Fariz, A; Abiri, Rambod; Taheri, Sima; Moradpoor, Mehdi

    2018-01-01

    Oil palm ( Elaeis guineensis Jacq) is one of the major sources of edible oil. Reducing the effect of Ganoderma, main cause of basal stem rot (BSR) on oil palm, is the main propose of this study. Understanding the oil palm defense mechanism against Ganoderma infection through monitoring changes in the secondary metabolite compounds levels before/after infection by Ganoderma under different fertilizing treatment is required. Oil palm requires macro- and microelements for growth and yield. Manipulating the nutrient for oil palm is a method to control the disease. The 3-4-month-old oil palm seedlings were given different macronutrient treatments to evaluate induction of defense related enzymes and production of secondary metabolite compounds in response to G. boninense inoculation. The observed trend of changes in the infected and uninfected seedlings was a slightly higher activity for β -1,3-glucanases, chitinase, peroxidase, and phenylalanine ammonia-lyase during the process of pathogenesis. It was found that PR proteins gave positive response to the interaction between oil palm seedlings and Ganoderma infection. Although the responses were activated systematically, they were short-lasting as the changes in enzymes activities appeared before the occurrence of visible symptoms. Effect of different nutrients doses was obviously observed among the results of the secondary metabolite compounds. Many identified/unidentified metabolite compounds were presented, of which some were involved in plant cell defense mechanism against pathogens, mostly belonging to alkaloids with bitter-tasting nitrogenous-compounds, and some had the potential to be used as new markers to detect basal stem rot at the initial step of disease.

  18. Antioxidant Enzyme Activities and Secondary Metabolite Profiling of Oil Palm Seedlings Treated with Combination of NPK Fertilizers Infected with Ganoderma boninense

    PubMed Central

    Mohidin, Hasmah; Idris, Abu Seman; Fariz, A.; Abiri, Rambod; Taheri, Sima; Moradpoor, Mehdi

    2018-01-01

    Oil palm (Elaeis guineensis Jacq) is one of the major sources of edible oil. Reducing the effect of Ganoderma, main cause of basal stem rot (BSR) on oil palm, is the main propose of this study. Understanding the oil palm defense mechanism against Ganoderma infection through monitoring changes in the secondary metabolite compounds levels before/after infection by Ganoderma under different fertilizing treatment is required. Oil palm requires macro- and microelements for growth and yield. Manipulating the nutrient for oil palm is a method to control the disease. The 3-4-month-old oil palm seedlings were given different macronutrient treatments to evaluate induction of defense related enzymes and production of secondary metabolite compounds in response to G. boninense inoculation. The observed trend of changes in the infected and uninfected seedlings was a slightly higher activity for β-1,3-glucanases, chitinase, peroxidase, and phenylalanine ammonia-lyase during the process of pathogenesis. It was found that PR proteins gave positive response to the interaction between oil palm seedlings and Ganoderma infection. Although the responses were activated systematically, they were short-lasting as the changes in enzymes activities appeared before the occurrence of visible symptoms. Effect of different nutrients doses was obviously observed among the results of the secondary metabolite compounds. Many identified/unidentified metabolite compounds were presented, of which some were involved in plant cell defense mechanism against pathogens, mostly belonging to alkaloids with bitter-tasting nitrogenous-compounds, and some had the potential to be used as new markers to detect basal stem rot at the initial step of disease. PMID:29721500

  19. Mutagenicity of 1-nitropyrene metabolites from lung S9.

    PubMed

    King, L C; Kohan, M J; Ball, L M; Lewtas, J

    1984-04-01

    The mutagenicity of 1-nitropyrene metabolites from rabbit lung S9 incubates was evaluated using the Salmonella typhimurium plate incorporation assay with strain TA98, with and without Aroclor-induced rat liver S9. The following metabolites were isolated, identified and quantitated by HPLC: 1-nitropyrene -4,5- or -9,10-dihydrodiol (K-DHD), N-acetyl-1-aminopyrene ( NAAP ), 1-aminopyrene (1-AMP), 10-hydroxy-1-nitropyrene, 4-, 5-, 6-, 8- or 9-monohydroxy-1-nitropyrene (phenols) and 3-hydroxy-1-nitropyrene. The predominant metabolites formed by lung S9 incubates were K-DHD, 3-OH-1-nitropyrene and phenols. All of the metabolites were mutagenic in the absence of the exogenous rat liver S9 metabolic activation system, and several, including two unidentified metabolites were more potent than the parent 1-nitropyrene. The mutagenicity of 3 of the metabolites ( NAAP , 10-OH-1-nitropyrene and phenols) were enhanced by S9 while most of the other metabolites were less mutagenic in the presence of S9. These results indicate that lung tissue is capable of both oxidative and reductive metabolism which produced mutagenic metabolites, several of which were more potent than the parent compound, 1-NP.

  20. Carrier-Mediated Prodrug Uptake to Improve the Oral Bioavailability of Polar Drugs: An Application to an Oseltamivir Analogue.

    PubMed

    Incecayir, Tuba; Sun, Jing; Tsume, Yasuhiro; Xu, Hao; Gose, Tomoka; Nakanishi, Takeo; Tamai, Ikumi; Hilfinger, John; Lipka, Elke; Amidon, Gordon L

    2016-02-01

    The goal of this study was to improve the intestinal mucosal cell membrane permeability of the poorly absorbed guanidino analogue of a neuraminidase inhibitor, oseltamivir carboxylate (GOC) using a carrier-mediated strategy. Valyl amino acid prodrug of GOC with isopropyl-methylene-dioxy linker (GOC-ISP-Val) was evaluated as the potential substrate for intestinal oligopeptide transporter, hPEPT1 in Xenopus laevis oocytes heterologously expressing hPEPT1, and an intestinal mouse perfusion system. The diastereomers of GOC-ISP-Val were assessed for chemical and metabolic stability. Permeability of GOC-ISP-Val was determined in Caco-2 cells and mice. Diastereomer 2 was about 2 times more stable than diastereomer 1 in simulated intestinal fluid and rapidly hydrolyzed to the parent drug in cell homogenates. The prodrug had a 9 times-enhanced apparent permeability (P(app)) in Caco-2 cells compared with the parent drug. Both diastereomer exhibited high effective permeability (P(eff)) in mice, 6.32 ± 3.12 and 5.20 ± 2.81 × 10(-5) cm/s for diastereomer 1 and 2, respectively. GOC-ISP-Val was found to be a substrate of hPEPT1. Overall, this study indicates that the prodrug, GOC-ISP-Val, seems to be a promising oral anti-influenza agent that has sufficient stability at physiologically relevant pHs before absorption, significantly improved permeability via hPEPT1 and potentially rapid activation in the intestinal cells. Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  1. Uncovering production of specialized metabolites by Streptomyces argillaceus: Activation of cryptic biosynthesis gene clusters using nutritional and genetic approaches.

    PubMed

    Becerril, Adriana; Álvarez, Susana; Braña, Alfredo F; Rico, Sergio; Díaz, Margarita; Santamaría, Ramón I; Salas, José A; Méndez, Carmen

    2018-01-01

    Sequencing of Streptomyces genomes has revealed they harbor a high number of biosynthesis gene cluster (BGC), which uncovered their enormous potentiality to encode specialized metabolites. However, these metabolites are not usually produced under standard laboratory conditions. In this manuscript we report the activation of BGCs for antimycins, carotenoids, germicidins and desferrioxamine compounds in Streptomyces argillaceus, and the identification of the encoded compounds. This was achieved by following different strategies, including changing the growth conditions, heterologous expression of the cluster and inactivating the adpAa or overexpressing the abrC3 global regulatory genes. In addition, three new carotenoid compounds have been identified.

  2. Benzene's metabolites alter c-MYB activity via reactive oxygen species in HD3 cells.

    PubMed

    Wan, Joanne; Winn, Louise M

    2007-07-15

    Benzene is a known leukemogen that is metabolized to form reactive intermediates and reactive oxygen species (ROS). The c-Myb oncoprotein is a transcription factor that has a critical role in hematopoiesis. c-Myb transcript and protein have been overexpressed in a number of leukemias and cancers. Given c-Myb's role in hematopoiesis and leukemias, it is hypothesized that benzene interferes with the c-Myb signaling pathway and that this involves ROS. To investigate our hypothesis, we evaluated whether benzene, 1,4-benzoquinone, hydroquinone, phenol, and catechol generated ROS in chicken erythroblast HD3 cells, as measured by 5-(and-6)-chloromethyl-2',7'-dichlorodihydrofluorescein diacetate (DCFDA) and dihydrorhodamine-123 (DHR-123), and whether the addition of 100 U/ml of the antioxidating enzyme superoxide dismutase (SOD) could prevent ROS generation. Reduced to oxidized glutathione ratios (GSH:GSSG) were also assessed as well as hydroquinone and benzoquinone's effects on c-Myb protein levels and activation of a transiently transfected reporter construct. Finally we attempted to abrogate benzene metabolite mediated increases in c-Myb activity with the use of SOD. We found that benzoquinone, hydroquinone, and catechol increased DCFDA fluorescence, increased DHR-123 fluorescence, decreased GSH:GSSG ratios, and increased reporter construct expression after 24 h of exposure. SOD was able to prevent DCFDA fluorescence and c-Myb activity caused by benzoquinone and hydroquinone only. These results are consistent with other studies, which suggest metabolite differences in benzene-mediated toxicity. More importantly, this study supports the hypothesis that benzene may mediate its toxicity through ROS-mediated alterations in the c-Myb signaling pathway.

  3. Can Some Marine-Derived Fungal Metabolites Become Actual Anticancer Agents?

    PubMed Central

    Gomes, Nelson G. M.; Lefranc, Florence; Kijjoa, Anake; Kiss, Robert

    2015-01-01

    Marine fungi are known to produce structurally unique secondary metabolites, and more than 1000 marine fungal-derived metabolites have already been reported. Despite the absence of marine fungal-derived metabolites in the current clinical pipeline, dozens of them have been classified as potential chemotherapy candidates because of their anticancer activity. Over the last decade, several comprehensive reviews have covered the potential anticancer activity of marine fungal-derived metabolites. However, these reviews consider the term “cytotoxicity” to be synonymous with “anticancer agent”, which is not actually true. Indeed, a cytotoxic compound is by definition a poisonous compound. To become a potential anticancer agent, a cytotoxic compound must at least display (i) selectivity between normal and cancer cells (ii) activity against multidrug-resistant (MDR) cancer cells; and (iii) a preferentially non-apoptotic cell death mechanism, as it is now well known that a high proportion of cancer cells that resist chemotherapy are in fact apoptosis-resistant cancer cells against which pro-apoptotic drugs have more than limited efficacy. The present review thus focuses on the cytotoxic marine fungal-derived metabolites whose ability to kill cancer cells has been reported in the literature. Particular attention is paid to the compounds that kill cancer cells through non-apoptotic cell death mechanisms. PMID:26090846

  4. Can Some Marine-Derived Fungal Metabolites Become Actual Anticancer Agents?

    PubMed

    Gomes, Nelson G M; Lefranc, Florence; Kijjoa, Anake; Kiss, Robert

    2015-06-19

    Marine fungi are known to produce structurally unique secondary metabolites, and more than 1000 marine fungal-derived metabolites have already been reported. Despite the absence of marine fungal-derived metabolites in the current clinical pipeline, dozens of them have been classified as potential chemotherapy candidates because of their anticancer activity. Over the last decade, several comprehensive reviews have covered the potential anticancer activity of marine fungal-derived metabolites. However, these reviews consider the term "cytotoxicity" to be synonymous with "anticancer agent", which is not actually true. Indeed, a cytotoxic compound is by definition a poisonous compound. To become a potential anticancer agent, a cytotoxic compound must at least display (i) selectivity between normal and cancer cells (ii) activity against multidrug-resistant (MDR) cancer cells; and (iii) a preferentially non-apoptotic cell death mechanism, as it is now well known that a high proportion of cancer cells that resist chemotherapy are in fact apoptosis-resistant cancer cells against which pro-apoptotic drugs have more than limited efficacy. The present review thus focuses on the cytotoxic marine fungal-derived metabolites whose ability to kill cancer cells has been reported in the literature. Particular attention is paid to the compounds that kill cancer cells through non-apoptotic cell death mechanisms.

  5. Niacin and its metabolites as master regulators of macrophage activation.

    PubMed

    Montserrat-de la Paz, Sergio; Naranjo, M Carmen; Lopez, Sergio; Abia, Rocio; Muriana, Francisco J Garcia; Bermudez, Beatriz

    2017-01-01

    Niacin is a broad-spectrum lipid-regulating drug used for clinical therapy of chronic high-grade inflammatory diseases. However, the mechanisms by which either niacin or the byproducts of its catabolism ameliorate these inflammatory diseases are not clear yet. Human circulating monocytes and mature macrophages were used to analyze the effects of niacin and its metabolites (NAM, NUA and 2-Pyr) on oxidative stress, plasticity and inflammatory response by using biochemical, flow cytometry, quantitative real-time PCR and Western blot technologies. Niacin, NAM and 2-Pyr significantly decreased ROS, NO and NOS2 expression in LPS-treated human mature macrophages. Niacin and NAM skewed macrophage polarization toward antiinflammatory M2 macrophage whereas a trend toward proinflammatory M1 macrophage was noted following treatment with NUA. Niacin and NAM also reduced the inflammatory competence of LPS-treated human mature macrophages and promoted bias toward antiinflammatory CD14 + CD16 ++ nonclassical human primary monocytes. This study reveals for the first time that niacin and its metabolites possess antioxidant, reprogramming and antiinflammatory properties on human primary monocytes and monocyte-derived macrophages. Our findings imply a new understanding of the mechanisms by which niacin and its metabolites favor a continuous and gradual plasticity process in the human monocyte/macrophage system. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Cellular stress created by intermediary metabolite imbalances.

    PubMed

    Lee, Sang Jun; Trostel, Andrei; Le, Phuoc; Harinarayanan, Rajendran; Fitzgerald, Peter C; Adhya, Sankar

    2009-11-17

    Small molecules generally activate or inhibit gene transcription as externally added substrates or as internally accumulated end-products, respectively. Rarely has a connection been made that links an intracellular intermediary metabolite as a signal of gene expression. We report that a perturbation in the critical step of a metabolic pathway--the D-galactose amphibolic pathway--changes the dynamics of the pathways leading to accumulation of the intermediary metabolite UDP-galactose. This accumulation causes cell stress and transduces signals that alter gene expression so as to cope with the stress by restoring balance in the metabolite pool. This underscores the importance of studying the global effects of alterations in the level of intermediary metabolites in causing stress and coping with it by transducing signals to genes to reach a stable state of equilibrium (homeostasis). Such studies are an essential component in the integration of metabolomics, proteomics, and transcriptomics.

  7. An Invasive Plant Promotes Its Arbuscular Mycorrhizal Symbioses and Competitiveness through Its Secondary Metabolites: Indirect Evidence from Activated Carbon

    PubMed Central

    Yuan, Yongge; Tang, Jianjun; Leng, Dong; Hu, Shuijin; Yong, Jean W. H.; Chen, Xin

    2014-01-01

    Secondary metabolites released by invasive plants can increase their competitive ability by affecting native plants, herbivores, and pathogens at the invaded land. Whether these secondary metabolites affect the invasive plant itself, directly or indirectly through microorganisms, however, has not been well documented. Here we tested whether activated carbon (AC), a well-known absorbent for secondary metabolites, affect arbuscular mycorrhizal (AM) symbioses and competitive ability in an invasive plant. We conducted three experiments (experiments 1–3) with the invasive forb Solidago canadensis and the native Kummerowia striata. Experiment 1 determined whether AC altered soil properties, levels of the main secondary metabolites in the soil, plant growth, and AMF communities associated with S. canadensis and K. striata. Experiment 2 determined whether AC affected colonization of S. canadensis by five AMF, which were added to sterilized soil. Experiment 3 determined the competitive ability of S. canadensis in the presence and absence of AMF and AC. In experiment 1, AC greatly decreased the concentrations of the main secondary metabolites in soil, and the changes in concentrations were closely related with the changes of AMF in S. canadensis roots. In experiment 2, AC inhibited the AMF Glomus versiforme and G. geosporum but promoted G. mosseae and G. diaphanum in the soil and also in S. canadensis roots. In experiment 3, AC reduced S. canadensis competitive ability in the presence but not in the absence of AMF. Our results provided indirect evidence that the secondary metabolites (which can be absorbed by AC) of the invasive plant S. canadensis may promote S. canadensis competitiveness by enhancing its own AMF symbionts. PMID:24817325

  8. Estrogenic and androgenic activities of TBBA and TBMEPH, metabolites of novel brominated flame retardants, and selected bisphenols, using the XenoScreen XL YES/YAS assay.

    PubMed

    Fic, Anja; Žegura, Bojana; Gramec, Darja; Mašič, Lucija Peterlin

    2014-10-01

    The present study investigated and compared the estrogenic and androgenic activities of the three different classes of environmental pollutants and their metabolites using the XenoScreen XL YES/YAS assay, which has advantages compared with the original YES/YAS protocol. Contrary to the parent brominated flame retardants TBB and TBPH, which demonstrated no or very weak (anti)estrogenic or (anti)androgenic activities, their metabolites, TBBA and TBMEPH, exhibited anti-estrogenic (IC50 for TBBA=31.75 μM and IC50 for TBMEPH=0.265 μM) and anti-androgenic (IC50 for TBBA=73.95 μM and IC50 for TBMEPH=2.92 μM) activities. These results reveal that metabolism can enhance the anti-estrogenic and anti-androgenic effects of these two novel brominated flame retardants. Based on the activities of BPAF, BPF, BPA and MBP, we can conclude that the XenoScreen XL YES/YAS assay gives comparable results to the (anti)estrogenic or (anti)androgenic assays that are reported in the literature. For BPA, it was confirmed previously that the metabolite formed after an ipso-reaction (hydroxycumyl alcohol) exhibited higher estrogenic activity compared with the parent BPA, but this was not confirmed for BPAF and BPF ipso-metabolites, which were not active in the XenoScreen YES/YAS assay. Among the substituted BPA analogues, bis-GMA exhibited weak anti-estrogenic activity, BADGE demonstrated weak anti-estrogenic and anti-androgenic activities (IC50=13.73 μM), and the hydrolysed product BADGE·2H2O demonstrated no (anti)estrogenic or (anti)androgenic activities. Copyright © 2014. Published by Elsevier Ltd.

  9. Using Molecular Networking for Microbial Secondary Metabolite Bioprospecting.

    PubMed

    Purves, Kevin; Macintyre, Lynsey; Brennan, Debra; Hreggviðsson, Guðmundur Ó; Kuttner, Eva; Ásgeirsdóttir, Margrét E; Young, Louise C; Green, David H; Edrada-Ebel, Ruangelie; Duncan, Katherine R

    2016-01-08

    The oceans represent an understudied resource for the isolation of bacteria with the potential to produce novel secondary metabolites. In particular, actinomyces are well known to produce chemically diverse metabolites with a wide range of biological activities. This study characterised spore-forming bacteria from both Scottish and Antarctic sediments to assess the influence of isolation location on secondary metabolite production. Due to the selective isolation method used, all 85 isolates belonged to the phyla Firmicutes and Actinobacteria, with the majority of isolates belonging to the genera Bacillus and Streptomyces. Based on morphology, thirty-eight isolates were chosen for chemical investigation. Molecular networking based on chemical profiles (HR-MS/MS) of fermentation extracts was used to compare complex metabolite extracts. The results revealed 40% and 42% of parent ions were produced by Antarctic and Scottish isolated bacteria, respectively, and only 8% of networked metabolites were shared between these locations, implying a high degree of biogeographic influence upon secondary metabolite production. The resulting molecular network contained over 3500 parent ions with a mass range of m/z 149-2558 illustrating the wealth of metabolites produced. Furthermore, seven fermentation extracts showed bioactivity against epithelial colon adenocarcinoma cells, demonstrating the potential for the discovery of novel bioactive compounds from these understudied locations.

  10. Using Molecular Networking for Microbial Secondary Metabolite Bioprospecting

    PubMed Central

    Purves, Kevin; Macintyre, Lynsey; Brennan, Debra; Hreggviðsson, Guðmundur Ó.; Kuttner, Eva; Ásgeirsdóttir, Margrét E.; Young, Louise C.; Green, David H.; Edrada-Ebel, Ruangelie; Duncan, Katherine R.

    2016-01-01

    The oceans represent an understudied resource for the isolation of bacteria with the potential to produce novel secondary metabolites. In particular, actinomyces are well known to produce chemically diverse metabolites with a wide range of biological activities. This study characterised spore-forming bacteria from both Scottish and Antarctic sediments to assess the influence of isolation location on secondary metabolite production. Due to the selective isolation method used, all 85 isolates belonged to the phyla Firmicutes and Actinobacteria, with the majority of isolates belonging to the genera Bacillus and Streptomyces. Based on morphology, thirty-eight isolates were chosen for chemical investigation. Molecular networking based on chemical profiles (HR-MS/MS) of fermentation extracts was used to compare complex metabolite extracts. The results revealed 40% and 42% of parent ions were produced by Antarctic and Scottish isolated bacteria, respectively, and only 8% of networked metabolites were shared between these locations, implying a high degree of biogeographic influence upon secondary metabolite production. The resulting molecular network contained over 3500 parent ions with a mass range of m/z 149–2558 illustrating the wealth of metabolites produced. Furthermore, seven fermentation extracts showed bioactivity against epithelial colon adenocarcinoma cells, demonstrating the potential for the discovery of novel bioactive compounds from these understudied locations. PMID:26761036

  11. Anti-rheumatoid Activity of Secondary Metabolites Produced by Endophytic Chaetomium globosum

    PubMed Central

    Abdel-Azeem, Ahmed M.; Zaki, Sherif M.; Khalil, Waleed F.; Makhlouf, Noha A.; Farghaly, Lamiaa M.

    2016-01-01

    The aim of the present study was to investigate the anti-rheumatoid activity of secondary metabolites produced by endophytic mycobiota in Egypt. A total of 27 endophytic fungi were isolated from 10 dominant medicinal plant host species in Wadi Tala, Saint Katherine Protectorate, arid Sinai, Egypt. Of those taxa, seven isolates of Chaetomium globosum (CG1–CG7), being the most frequent taxon, were recovered from seven different host plants and screened for production of active anti-inflammatory metabolites. Isolates were cultivated on half – strength potato dextrose broth for 21 days at 28°C on a rotatory shaker at 180 rpm, and extracted in ethyl acetate and methanol, respectively. The probable inhibitory effects of both extracts against an adjuvant induced arthritis (AIA) rat model were examined and compared with the effects of methotrexate (MTX) as a standard disease-modifying anti-rheumatoid drug. Disease activity and mobility scoring of AIA, histopathology and transmission electron microscopy (TEM) were used to evaluate probable inhibitory roles. A significant reduction (P < 0.05) in the severity of arthritis was observed in both the methanolic extract of CG6 (MCG6) and MTX treatment groups 6 days after treatment commenced. The average arthritis score of the MCG6 treatment group was (10.7 ± 0.82) compared to (13.8 ± 0.98) in the positive control group. The mobility score of the MCG6 treatment group (1.50 ± 0.55) was significantly lower than that of the positive control group (3.33 ± 0.82). In contrast, the ethyl acetate extract of CG6 (EACG6) treatment group showed no improvements in arthritis and mobility scores in AIA model rats. Histopathology and TEM findings confirmed the observation. Isolate CG6 was subjected to sequencing for confirmation of phenotypic identification. The internal transcribed spacer (ITS) 1–5.8 s – ITS2 rDNA sequences obtained were compared with those deposited in the GenBank Database and registered with accession number KC

  12. Antimicrobial and Cytotoxic Activity of Extracts of Ferula heuffelii Griseb. ex Heuff. and Its Metabolites.

    PubMed

    Pavlović, Ivan; Petrović, Silvana; Milenković, Marina; Stanojković, Tatjana; Nikolić, Dejan; Krunić, Aleksej; Niketić, Marjan

    2015-10-01

    The antimicrobial and cytotoxic activities of isolates (CHCl3 and MeOH extracts and selected metabolites) obtained from the underground parts of the Balkan endemic plant Ferula heuffelii Griseb. ex Heuff. were assessed. The CHCl3 and MeOH extracts exhibited moderate antimicrobial activity, being more pronounced against Gram-positive than Gram-negative bacteria, especially against Staphylococcus aureus (MIC=12.5 μg/ml for both extracts) and Micrococcus luteus (MIC=50 and 12.5 μg/ml, resp.). Among the tested metabolites, (6E)-1-(2,4-dihydroxyphenyl)-3,7,11-trimethyl-3-vinyldodeca-6,10-dien-1-one (2) and (2S*,3R*)-2-[(3E)-4,8-dimethylnona-3,7-dien-1-yl]-2,3-dihydro-7-hydroxy-2,3-dimethylfuro[3,2-c]coumarin (4) demonstrated the best antimicrobial activity. Compounds 2 and 4 both strongly inhibited the growth of M. luteus (MIC=11.2 and 5.2 μM, resp.) and Staphylococcus epidermidis (MIC=22.5 and 10.5 μM, resp.) and compound 2 additionally also the growth of Bacillus subtilis (MIC=11.2 μM). The cytotoxic activity of the isolates was tested against three human cancer cell lines, viz., cervical adenocarcinoma (HeLa), chronic myelogenous leukemia (K562), and breast cancer (MCF-7) cells. The CHCl3 extract exhibited strong cytotoxic activity against all cell lines (IC50 <11.0 μg/ml). All compounds strongly inhibited the growth of the K562 and HeLa cell lines. Compound 4 exhibited also a strong activity against the MCF-7 cell line, comparable to that of cisplatin (IC50 =22.32±1.32 vs. 18.67±0.75μM). Copyright © 2015 Verlag Helvetica Chimica Acta AG, Zürich.

  13. Secondary Metabolites, Glandular Trichomes and Biological Activity of Sideritis montana L. subsp. montana from Central Italy.

    PubMed

    Venditti, Alessandro; Bianco, Armandodoriano; Frezza, Claudio; Serafini, Mauro; Giacomello, Ginevra; Giuliani, Claudia; Bramucci, Massimo; Quassinti, Luana; Lupidi, Giulio; Lucarini, Domenico; Papa, Fabrizio; Maggi, Filippo

    2016-10-01

    Sideritis montana subsp. montana is a small annual herb occurring in countries bordering the Mediterranean and Balkan regions. The secondary metabolism of this plant has not been fully explored so far. The aim of the present study was to understand the complex mixture of secondary metabolites and the type of secretory structures. The polar constituents were isolated by column chromatography from the ethanolic extract, and their structure was elucidated by NMR and MS. The essential oil was isolated by hydrodistillation and analysed by GC/MS. The plant indumentum was studied by light and scanning electron microscopy. To complete the work, the essential oil antioxidant activity and cytotoxicity on tumor cells were evaluated by DPPH, ABTS, FRAP, and MTT methods. Four different classes of secondary metabolites were isolated, namely flavonoids, caffeoylquinic derivatives, glycosidic hydroquinones and iridoids. The essential oil was mainly characterized by sesquiterpenene hydrocarbons. Peltate and long-capitate hairs were the main sites where terpenes and polar constituents are produced. The secondary metabolites found in S. montana subsp. montana are of chemotaxonomic interest, some of them being typical of the genus Sideritis. The trichomes types observed partially differ from those described in other members of the genus Sideritis. The essential oil showed noteworthy inhibition on tumor cells. © 2016 Wiley-VHCA AG, Zürich.

  14. The effect of the lunar cycle on fecal cortisol metabolite levels and foraging ecology of nocturnally and diurnally active spiny mice.

    PubMed

    Gutman, Roee; Dayan, Tamar; Levy, Ofir; Schubert, Iris; Kronfeld-Schor, Noga

    2011-01-01

    We studied stress hormones and foraging of nocturnal Acomys cahirinus and diurnal A. russatus in field populations as well as in two field enclosures populated by both species and two field enclosures with individuals of A. russatus alone. When alone, A. russatus individuals become also nocturnally active. We asked whether nocturnally active A. russatus will respond to moon phase and whether this response will be obtained also in diurnally active individuals. We studied giving-up densities (GUDs) in artificial foraging patches and fecal cortisol metabolite levels. Both species exhibited elevated fecal cortisol metabolite levels and foraged to higher GUDs in full moon nights; thus A. russatus retains physiological response and behavioral patterns that correlate with full moon conditions, as can be expected in nocturnal rodents, in spite of its diurnal activity. The endocrinological and behavioral response of this diurnal species to moon phase reflects its evolutionary heritage.

  15. [Effective productions of plant secondary metabolites having antitumor activity by plant cell and tissue cultures].

    PubMed

    Taniguchi, Shoko

    2005-06-01

    Methods for the effective production of plant secondary metabolites with antitumor activity using plant cell and tissue cultures were developed. The factors in tannin productivity were investigated using culture strains producing different types of hydrolyzable tannins, i.e., gallotannins (mixture of galloylglucoses), ellagi-, and dehydroellagitannins. Production of ellagi- and dehydroellagitannins was affected by the concentrations and ratio of nitrogen sources in the medium. The formation of oligomeric ellagitannins in shoots of Oenothera tetraptera was correlated with the differentiation of tissues. Cultured cells of Eriobotrya japonica producing ursane- and oleanane-type triterpenes with antitumor activities were also established.

  16. Itaconate is an anti-inflammatory metabolite that activates Nrf2 via alkylation of KEAP1.

    PubMed

    Mills, Evanna L; Ryan, Dylan G; Prag, Hiran A; Dikovskaya, Dina; Menon, Deepthi; Zaslona, Zbigniew; Jedrychowski, Mark P; Costa, Ana S H; Higgins, Maureen; Hams, Emily; Szpyt, John; Runtsch, Marah C; King, Martin S; McGouran, Joanna F; Fischer, Roman; Kessler, Benedikt M; McGettrick, Anne F; Hughes, Mark M; Carroll, Richard G; Booty, Lee M; Knatko, Elena V; Meakin, Paul J; Ashford, Michael L J; Modis, Louise K; Brunori, Gino; Sévin, Daniel C; Fallon, Padraic G; Caldwell, Stuart T; Kunji, Edmund R S; Chouchani, Edward T; Frezza, Christian; Dinkova-Kostova, Albena T; Hartley, Richard C; Murphy, Michael P; O'Neill, Luke A

    2018-04-05

    The endogenous metabolite itaconate has recently emerged as a regulator of macrophage function, but its precise mechanism of action remains poorly understood. Here we show that itaconate is required for the activation of the anti-inflammatory transcription factor Nrf2 (also known as NFE2L2) by lipopolysaccharide in mouse and human macrophages. We find that itaconate directly modifies proteins via alkylation of cysteine residues. Itaconate alkylates cysteine residues 151, 257, 288, 273 and 297 on the protein KEAP1, enabling Nrf2 to increase the expression of downstream genes with anti-oxidant and anti-inflammatory capacities. The activation of Nrf2 is required for the anti-inflammatory action of itaconate. We describe the use of a new cell-permeable itaconate derivative, 4-octyl itaconate, which is protective against lipopolysaccharide-induced lethality in vivo and decreases cytokine production. We show that type I interferons boost the expression of Irg1 (also known as Acod1) and itaconate production. Furthermore, we find that itaconate production limits the type I interferon response, indicating a negative feedback loop that involves interferons and itaconate. Our findings demonstrate that itaconate is a crucial anti-inflammatory metabolite that acts via Nrf2 to limit inflammation and modulate type I interferons.

  17. Characterization of the methemoglobin forming metabolites of benzocaine and lidocaine.

    PubMed

    Hartman, Neil; Zhou, Hongfei; Mao, Jinzhe; Mans, Daniel; Boyne, Michael; Patel, Vikram; Colatsky, Thomas

    2017-05-01

    1. Topical anesthesia with benzocaine or lidocaine occasionally causes methemoglobinemia, an uncommon but potentially fatal disorder where the blood has a reduced ability to transport oxygen. Previous in vitro studies using human whole blood have shown that benzocaine causes more methemoglobin (MetHb) formation than lidocaine, and that both compounds require metabolic transformation to form the MetHb producing species. In the current investigation, the active species of benzocaine forming the MetHb was investigated. 2. HPLC analysis of benzocaine samples incubated with human hepatic S9 showed the formation of a peak with the same UV spectrum and retention time as benzocaine hydroxylamine (BenzNOH). To confirm the activity of BenzNOH, MetHb production following exposure to the compound was determined in whole human blood using an Avoximeter 4000 CO-oximeter. 3. BenzNOH produced MetHb in a concentration dependent manner without the need for metabolic activation. Benzocaine in the presence of metabolic activation required a concentration of 500 μM to produce a similar degree of MetHb formation as 20 μM BenzNOH without activation. Previous work suggested that two metabolites of lidocaine may also form MetHb; N-hydroxyxylidine and 4-hydroxyxylidine. Of these two metabolites 4-hydroxyxylidine produced the most MetHb in whole blood in vitro in the absence of metabolic activation, however BenzNOH produced up to 14.2 times more MetHb than 4-hydroxyxylidine at a similar concentration. 4. These results suggest that the ability of benzocaine to form MetHb is likely to be mediated through its hydroxylamine metabolite and that this metabolite is inherently more active than the potentially MetHb-forming metabolites of lidocaine.

  18. Natural metabolites for parasitic weed management.

    PubMed

    Vurro, Maurizio; Boari, Angela; Evidente, Antonio; Andolfi, Anna; Zermane, Nadjia

    2009-05-01

    Compounds of natural origin, such as phytotoxins produced by fungi or natural amino acids, could be used in parasitic weed management strategies by interfering with the early growth stages of the parasites. These metabolites could inhibit seed germination or germ tube elongation, so preventing attachment to the host plant, or, conversely, stimulate seed germination in the absence of the host, contributing to a reduction in the parasite seed bank. Some of the fungal metabolites assayed were very active even at very low concentrations, such as some macrocyclic trichothecenes, which at 0.1 microM strongly suppressed the germination of Orobanche ramosa L. seeds. Interesting results were also obtained with some novel toxins, such as phyllostictine A, highly active in reducing germ tube elongation and seed germination both of O. ramosa and of Cuscuta campestris Yuncker. Among the amino acids tested, methionine and arginine were particularly interesting, as they were able to suppress seed germination at concentrations lower than 1 mM. Some of the fungal metabolites tested were also able to stimulate the germination of O. ramosa seeds. The major findings in this research field are described and discussed.

  19. Synthesis of an Albendazole Metabolite: Characterization and HPLC Determination

    ERIC Educational Resources Information Center

    Mahler, Graciela; Davyt, Danilo; Gordon, Sandra; Incerti, Marcelo; Nunez, Ivana; Pezaroglo, Horacio; Scarone, Laura; Serra, Gloria; Silvera, Mauricio; Manta, Eduardo

    2008-01-01

    In this laboratory activity, students are introduced to the synthesis of an albendazole metabolite obtained by a sulfide oxidation reaction. Albendazole as well as its metabolite, albendazole sulfoxide, are used as anthelmintic drugs. The oxidation reagent is H[subscript 2]O[subscript 2] in acetic acid. The reaction is environmental friendly,…

  20. Formononetin, a phyto-oestrogen, and its metabolites up-regulate interleukin-4 production in activated T cells via increased AP-1 DNA binding activity

    PubMed Central

    Park, Jin; Kim, Seung H; Cho, Daeho; Kim, Tae S

    2005-01-01

    Phyto-oestrogens are polyphenolic non-steroidal plant compounds with oestrogen-like biological activity. Phyto-oestrogens have many biological effects including oestrogen agonist/antagonist properties. However, the effect of phyto-oestrogens on allergic responses remains unclear. In this study we investigated whether formononetin, a phyto-oestrogen, and its metabolites, daidzein and equol, affect production of interleukin-4 (IL-4), a pro-inflammatory cytokine closely associated with allergic immune response, in primary CD4+ T cells and EL4 T lymphoma cells. Formononetin, daidzein and equol significantly enhanced IL-4 production from both CD4+ T cells and EL4 cells in a dose-dependent manner. Formononetin, daidzein and equol also enhanced IL-4 gene promoter activity in EL4 cells transiently transfected with IL-4 gene promoter constructs, but this effect was impaired in EL4 cells transfected with an IL-4 promoter construct deleted of P4 site carrying nuclear factor of activated T cells (NF-AT) and activator protein-1 (AP-1) binding sites. In addition, formononetin, daidzein and equol increased AP-1 DNA binding activities while did not affect NF-AT DNA binding activities. The enhancing effects on IL-4 production and AP-1 DNA binding activities were abrogated by specific inhibitors for phosphatidylinositol-3-kinase (PI3K), protein kinase C (PKC) and p38 mitogen-activated protein kinase (MAPK), indicating that formononetin, daidzein and equol might enhance IL-4 production by increased activation of AP-1 through the PI3-K/PKC/p38 MAPK signalling pathway. These results suggest that phyto-oestrogens and some of their metabolites may increase allergic responses via the enhancement of IL-4 production in T cells. PMID:16108819

  1. Alpha-keto acid metabolites of organoselenium compounds inhibit histone deacetylase activity in human colon cancer cells.

    PubMed

    Nian, Hui; Bisson, William H; Dashwood, Wan-Mohaiza; Pinto, John T; Dashwood, Roderick H

    2009-08-01

    Methylselenocysteine (MSC) and selenomethionine (SM) are two organoselenium compounds receiving interest for their potential anticancer properties. These compounds can be converted to beta-methylselenopyruvate (MSP) and alpha-keto-gamma-methylselenobutyrate (KMSB), alpha-keto acid metabolites that share structural features with the histone deacetylase (HDAC) inhibitor butyrate. We tested the organoselenium compounds in an in vitro assay with human HDAC1 and HDAC8; whereas SM and MSC had little or no activity up to 2 mM, MSP and KMSB caused dose-dependent inhibition of HDAC activity. Subsequent experiments identified MSP as a competitive inhibitor of HDAC8, and computational modeling supported a mechanism involving reversible interaction with the active site zinc atom. In human colon cancer cells, acetylated histone H3 levels were increased during the period 0.5-48 h after treatment with MSP and KMSB, and there was dose-dependent inhibition of HDAC activity. The proportion of cells occupying G(2)/M of the cell cycle was increased at 10-50 microM MSP and KMSB, and apoptosis was induced, as evidenced by morphological changes, Annexin V staining and increased cleaved caspase-3, -6, -7, -9 and poly(adenosine diphosphate-ribose)polymerase. P21WAF1, a well-established target gene of clinically used HDAC inhibitors, was increased in MSP- and KMSB-treated colon cancer cells at both the messenger RNA and protein level, and there was enhanced P21WAF1 promoter activity. These studies confirm that in addition to targeting redox-sensitive signaling molecules, alpha-keto acid metabolites of organoselenium compounds alter HDAC activity and histone acetylation status in colon cancer cells, as recently observed in human prostate cancer cells.

  2. CYP2C19*17 increases clopidogrel-mediated platelet inhibition but does not alter the pharmacokinetics of the active metabolite of clopidogrel.

    PubMed

    Pedersen, Rasmus Steen; Nielsen, Flemming; Stage, Tore Bjerregaard; Vinholt, Pernille Just; el Achwah, Alaa Bilal; Damkier, Per; Brosen, Kim

    2014-11-01

    The aim of the present study was to determine the impact of CYP2C19*17 on the pharmacokinetics and pharmacodynamics of the active metabolite of clopidogrel and the pharmacokinetics of proguanil. Thus, we conducted an open-label two-phase cross-over study in 31 healthy male volunteers (11 CYP2C19*1/*1, 11 CYP2C19*1/*17 and nine CYP2C19*17/*17). In Phase A, the pharmacokinetics of the derivatized active metabolite of clopidogrel (CAMD) and platelet function were determined after administration of a single oral dose of 600 mg clopidogrel (Plavix; Sanofi-Avensis, Horsholm, Denmark). In Phase B, the pharmacokinetics of proguanil and its metabolites cycloguanil and 4-chlorphenylbiguanide (4-CPB) were determined in 29 of 31 subjects after a single oral dose of 200 mg proguanil given as the combination drug Malarone (GlaxoSmithKline Pharma, Brondby, Denmark). Significant correlations were found between the area under the time-concentration curve (AUC0-∞ ) of CAMD and both the absolute ADP-induced P2Y12 receptor-activated platelet aggregation (r = -0.60, P = 0.0007) and the percentage inhibition of aggregation (r = 0.59, P = 0.0009). In addition, the CYP2C19*17/*17 and CYP2C19*1/*17 genotype groups had significantly higher percentage inhibition of platelet aggregation compared with the CYP2C19*1/*1 subjects (geometric mean percentage inhibition of 84%, 73% and 63%, respectively; P = 0.014). Neither the absolute ADP-induced P2Y12 receptor-activated platelet aggregation, exposure to CAMD nor the pharmacokinetic parameters of proguanil, cycloguanil and 4-CPB exhibited any significant differences among the genotype groups. In conclusion, carriers of CYP2C19*17 exhibit higher percentage inhibition of platelet aggregation, but do not have significantly lower absolute P2Y12 receptor-activated platelet aggregation or higher exposure to the active metabolite after a single oral administration of 600 mg clopidogrel. © 2014 Wiley Publishing Asia Pty Ltd.

  3. A New Paradigm for Known Metabolite Identification in Metabonomics/Metabolomics: Metabolite Identification Efficiency

    PubMed Central

    Everett, Jeremy R.

    2015-01-01

    A new paradigm is proposed for assessing confidence in the identification of known metabolites in metabonomics studies using NMR spectroscopy approaches. This new paradigm is based upon the analysis of the amount of metabolite identification information retrieved from NMR spectra relative to the molecular size of the metabolite. Several new indices are proposed including: metabolite identification efficiency (MIE) and metabolite identification carbon efficiency (MICE), both of which can be easily calculated. These indices, together with some guidelines, can be used to provide a better indication of known metabolite identification confidence in metabonomics studies than existing methods. Since known metabolite identification in untargeted metabonomics studies is one of the key bottlenecks facing the science currently, it is hoped that these concepts based on molecular spectroscopic informatics, will find utility in the field. PMID:25750701

  4. A new paradigm for known metabolite identification in metabonomics/metabolomics: metabolite identification efficiency.

    PubMed

    Everett, Jeremy R

    2015-01-01

    A new paradigm is proposed for assessing confidence in the identification of known metabolites in metabonomics studies using NMR spectroscopy approaches. This new paradigm is based upon the analysis of the amount of metabolite identification information retrieved from NMR spectra relative to the molecular size of the metabolite. Several new indices are proposed including: metabolite identification efficiency (MIE) and metabolite identification carbon efficiency (MICE), both of which can be easily calculated. These indices, together with some guidelines, can be used to provide a better indication of known metabolite identification confidence in metabonomics studies than existing methods. Since known metabolite identification in untargeted metabonomics studies is one of the key bottlenecks facing the science currently, it is hoped that these concepts based on molecular spectroscopic informatics, will find utility in the field.

  5. Microbial secondary metabolites in homes in association with moisture damage and asthma.

    PubMed

    Kirjavainen, P V; Täubel, M; Karvonen, A M; Sulyok, M; Tiittanen, P; Krska, R; Hyvärinen, A; Pekkanen, J

    2016-06-01

    We aimed to characterize the presence of microbial secondary metabolites in homes and their association with moisture damage, mold, and asthma development. Living room floor dust was analyzed by LC-MS/MS for 333 secondary metabolites from 93 homes of 1-year-old children. Moisture damage was present in 15 living rooms. At 6 years, 8 children had active and 15 lifetime doctor-diagnosed asthma. The median number of different metabolites per house was 17 (range 8-29) and median sum load 65 (4-865) ng/m(2) . Overall 42 different metabolites were detected. The number of metabolites present tended to be higher in homes with mold odor or moisture damage. The higher sum loads and number of metabolites with loads over 10 ng/m(2) were associated with lower prevalence of active asthma at 6 years (aOR 0.06 (95% CI <0.001-0.96) and 0.05 (<0.001-0.56), respectively). None of the individual metabolites, which presence tended (P < 0.2) to be increased by moisture damage or mold, were associated with increased risk of asthma. Microbial secondary metabolites are ubiquitously present in home floor dust. Moisture damage and mold tend to increase their numbers and amount. There was no evidence indicating that the secondary metabolites determined would explain the association between moisture damage, mold, and the development of asthma. © 2015 The Authors. Indoor Air published by John Wiley & Sons Ltd.

  6. Yellow-Cedar, Callitropsis (Chamaecyparis) nootkatensis, Secondary Metabolites, Biological Activities, and Chemical Ecology.

    PubMed

    Karchesy, Joseph J; Kelsey, Rick G; González-Hernández, M P

    2018-05-01

    Yellow-cedar, Callitropsis nootkatensis, is prevalent in coastal forests of southeast Alaska, western Canada, and inland forests along the Cascades to northern California, USA. These trees have few microbial or animal pests, attributable in part to the distinct groups of biologically active secondary metabolites their tissues store for chemical defense. Here we summarize the new yellow-cedar compounds identified and their biological activities, plus new or expanded activities for tissues, extracts, essential oils and previously known compounds since the last review more than 40 years ago. Monoterpene hydrocarbons are the most abundant compounds in foliage, while heartwood contains substantial quantities of oxygenated monoterpenes and oxygenated sesquiterpenes, with one or more tropolones. Diterpenes occur in foliage and bark, whereas condensed tannins have been isolated from inner bark. Biological activities expressed by one or more compounds in these groups include fungicide, bactericide, sporicide, acaricide, insecticide, general cytotoxicity, antioxidant and human anticancer. The diversity of organisms impacted by whole tissues, essential oils, extracts, or individual compounds now encompasses ticks, fleas, termites, ants, mosquitoes, bacteria, a water mold, fungi and browsing animals. Nootkatone, is a heartwood component with sufficient activity against arthropods to warrant research focused toward potential development as a commercial repellent and biopesticide for ticks, mosquitoes and possibly other arthropods that vector human and animal pathogens.

  7. A validated HPLC-MS/MS assay for quantifying unstable pharmacologically active metabolites of clopidogrel in human plasma: application to a clinical pharmacokinetic study.

    PubMed

    Furlong, Michael T; Savant, Ishani; Yuan, Moucun; Scott, Laura; Mylott, William; Mariannino, Thomas; Kadiyala, Pathanjali; Roongta, Vikram; Arnold, Mark E

    2013-05-01

    Clopidogrel is prescribed for the treatment of Acute Coronary Syndrome and recent myocardial infarction, recent stroke, or established peripheral arterial disease. A sensitive and reliable high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) assay was developed and validated to enable reliable quantification of four diastereomeric and chemically reactive thiol metabolites, two of which are pharmacologically active, in human plasma. The metabolites were stabilized by alkylation of their reactive thiol moieties with 2-bromo-3'-methoxyacetophenone (MPB). Following organic solvent mediated-protein precipitation in a 96-well plate format, chromatographic separation was achieved by gradient elution on an Ascentis Express RP-amide column. Chromatographic conditions were optimized to ensure separation of the four derivatized active metabolites. Derivatized metabolites and stable isotope-labeled internal standards were detected by positive ion electrospray tandem mass spectrometry. The HPLC-MS/MS assay was validated over concentration ranges of 0.125-125 ng/mL for metabolites H1-H3 and 0.101-101 ng/mL for H4. Intra- and inter-assay precision values for replicate quality control samples were within 14.3% for all analytes during the assay validation. Mean quality control accuracy values were within ±6.3% of nominal values for all analytes. Assay recoveries were high (>79%). The four derivatized analytes were stable in human blood for at least 2 h at room temperature and on ice. The analytes were also stable in human plasma for at least 25 h at room temperature, 372 days at -20 °C and -70 °C, and following at least five freeze-thaw cycles. The validated assay was successfully applied to the quantification of all four thiol metabolites in human plasma in support of a human pharmacokinetic study. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Antimicrobial activities of secondary metabolites and phylogenetic study of sponge endosymbiotic bacteria, Bacillus sp. at Agatti Island, Lakshadweep Archipelago.

    PubMed

    Mohan, Gopi; Thipparamalai Thangappanpillai, Ajith Kumar; Ramasamy, Balagurunathan

    2016-09-01

    Twenty-one species of sponges were recorded under the class of Demospongiae and Calcareous sponges of which 19 species were new to Agatti reef. A total of 113 Sponge endosymbiotic bacterial strains were isolated from twenty-one species of sponges and screened for antimicrobial activity. Five bacterial strains of sponge endosymbiotic bacteria (SEB) namely SEB32, SEB33, SEB36, SEB43 and SEB51 showed antimicrobial activity against virulent marine fish pathogens such as Vibrio alginolyticus , Vibrio vulnificus , Vibrio parahaemolyticus , Aeromonas salmonicida , Flavobacterium sp., Edwardsiella sp., Proteus mirabilis and Citrobacter brackii . The secondary metabolites produced by SEB32 from sponge Dysidea fragilis (Montagu, 1818) [48] was selected with broad range of antibacterial activity and subjected for production, characterization by series of chromatography techniques and spectroscopic methods. Based on the results of FT-IR and mass spectrometry, the active molecule was tentatively predicted as "Pyrrol" and the structure is Pyrrolo[1,2 -a ]pyrazine-1,4-dione, hexahydro- with molecular formula of C7H10N2O2. The LC 50 of active molecule was 31 μg/ml and molecular weight of the metabolites was 154. The potential strain SEB32 was identified by gene sequence (GenBank Accession number JX985748) and identified as Bacillus sp. from GenBank database.

  9. Antimicrobial and antiprotozoal activities of secondary metabolites from the fungus Eurotium repens

    PubMed Central

    Gao, Jiangtao; Radwan, Mohamed M.; León, Francisco; Wang, Xiaoning; Jacob, Melissa R.; Tekwani, Babu L.; Khan, Shabana I.; Lupien, Shari; Hill, Robert A.; Dugan, Frank M.; Cutler, Horace G.

    2011-01-01

    In this study, we examined in vitro antibacterial, antifungal, antimalarial, and antileishmanial activities of secondary metabolites (1–8) isolated from the fungus Eurotium repens. All compounds showed mild to moderate antibacterial or antifungal or both activities except 7. The activity of compound 6 was the best of the group tested. The in vitro antimalarial evaluation of these compounds revealed that compounds 1–3, 5, and 6 showed antimalarial activities against both chloroquine-sensitive and chloroquine-resistant strains of Plasmodium falciparum with IC50 values in the range of 1.1–3.0 μg/ml without showing any cytotoxicity to the mammalian cells. Compound 5 displayed the highest antimalarial activity. Antileishmanial activity against Leishmania donovani promastigotes was observed for compounds 1–6 with IC50 values ranging from 6.2 to 23 μg/ml. Antileishmanial activity of compounds 5 and 6 (IC50 values of 7.5 and 6.2 μg/ml, respectively) was more potent than 1–4 (IC50 values ranging from 19–23 μg/ml). Compounds 7 and 8 did not show any antiprotozoal effect. Preliminary structure and activity relationship studies indicated that antibacterial, antifungal, antimalarial, and antileishmanial activities associated with phenol derivates (1–6) seem to be dependent on the number of double bonds in the side chain, which would be important for lead optimization in the future. PMID:23024574

  10. Streptomyces metabolites in divergent microbial interactions.

    PubMed

    Takano, Hideaki; Nishiyama, Tatsuya; Amano, Sho-ichi; Beppu, Teruhiko; Kobayashi, Michihiko; Ueda, Kenji

    2016-03-01

    Streptomyces and related bacteria produce a wide variety of secondary metabolites. Of these, many compounds have industrial applications, but the question of why this group of microorganism produces such various kinds of biologically active substances has not yet been clearly answered. Here, we overview the results from our studies on the novel function and role of Streptomyces metabolites. The diverged action of negative and positive influences onto the physiology of various microorganisms infers the occurrence of complex microbial interactions due to the effect of small molecules produced by Streptomyces. The interactions may serve as a basis for the constitution of biological community.

  11. Potential of small-molecule fungal metabolites in antiviral chemotherapy

    PubMed Central

    Roy, Biswajit G

    2017-01-01

    Various viral diseases, such as acquired immunodeficiency syndrome, influenza, and hepatitis, have emerged as leading causes of human death worldwide. Scientific endeavor since invention of DNA-dependent RNA polymerase of pox virus in 1967 resulted in better understanding of virus replication and development of various novel therapeutic strategies. Despite considerable advancement in every facet of drug discovery process, development of commercially viable, safe, and effective drugs for these viruses still remains a big challenge. Decades of intense research yielded a handful of natural and synthetic therapeutic options. But emergence of new viruses and drug-resistant viral strains had made new drug development process a never-ending battle. Small-molecule fungal metabolites due to their vast diversity, stereochemical complexity, and preapproved biocompatibility always remain an attractive source for new drug discovery. Though, exploration of therapeutic importance of fungal metabolites has started early with discovery of penicillin, recent prediction asserted that only a small percentage (5–10%) of fungal species have been identified and much less have been scientifically investigated. Therefore, exploration of new fungal metabolites, their bioassay, and subsequent mechanistic study bears huge importance in new drug discovery endeavors. Though no fungal metabolites so far approved for antiviral treatment, many of these exhibited high potential against various viral diseases. This review comprehensively discussed about antiviral activities of fungal metabolites of diverse origin against some important viral diseases. This also highlighted the mechanistic details of inhibition of viral replication along with structure–activity relationship of some common and important classes of fungal metabolites. PMID:28737040

  12. Plant-Derived Polyphenols in Human Health: Biological Activity, Metabolites and Putative Molecular Targets.

    PubMed

    Olivares-Vicente, Marilo; Barrajon-Catalan, Enrique; Herranz-Lopez, Maria; Segura-Carretero, Antonio; Joven, Jorge; Encinar, Jose Antonio; Micol, Vicente

    2018-01-01

    Hibiscus sabdariffa, Lippia citriodora, Rosmarinus officinalis and Olea europaea, are rich in bioactive compounds that represent most of the phenolic compounds' families and have exhibited potential benefits in human health. These plants have been used in folk medicine for their potential therapeutic properties in human chronic diseases. Recent evidence leads to postulate that polyphenols may account for such effects. Nevertheless, the compounds or metabolites that are responsible for reaching the molecular targets are unknown. data based on studies directly using complex extracts on cellular models, without considering metabolic aspects, have limited applicability. In contrast, studies exploring the absorption process, metabolites in the blood circulation and tissues have become essential to identify the intracellular final effectors that are responsible for extracts bioactivity. Once the cellular metabolites are identified using high-resolution mass spectrometry, docking techniques suppose a unique tool for virtually screening a large number of compounds on selected targets in order to elucidate their potential mechanisms. we provide an updated overview of the in vitro and in vivo studies on the toxicity, absorption, permeability, pharmacokinetics and cellular metabolism of bioactive compounds derived from the abovementioned plants to identify the potential compounds that are responsible for the observed health effects. we propose the use of targeted metabolomics followed by in silico studies to virtually screen identified metabolites on selected protein targets, in combination with the use of the candidate metabolites in cellular models, as the methods of choice for elucidating the molecular mechanisms of these compounds. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  13. Fungal Anticancer Metabolites: Synthesis Towards Drug Discovery.

    PubMed

    Barbero, Margherita; Artuso, Emma; Prandi, Cristina

    2018-01-01

    Fungi are a well-known and valuable source of compounds of therapeutic relevance, in particular of novel anticancer compounds. Although seldom obtainable through isolation from the natural source, the total organic synthesis still remains one of the most efficient alternatives to resupply them. Furthermore, natural product total synthesis is a valuable tool not only for discovery of new complex biologically active compounds but also for the development of innovative methodologies in enantioselective organic synthesis. We undertook an in-depth literature searching by using chemical bibliographic databases (SciFinder, Reaxys) in order to have a comprehensive insight into the wide research field. The literature has been then screened, refining the obtained results by subject terms focused on both biological activity and innovative synthetic procedures. The literature on fungal metabolites has been recently reviewed and these publications have been used as a base from which we consider the synthetic feasibility of the most promising compounds, in terms of anticancer properties and drug development. In this paper, compounds are classified according to their chemical structure. This review summarizes the anticancer potential of fungal metabolites, highlighting the role of total synthesis outlining the feasibility of innovative synthetic procedures that facilitate the development of fungal metabolites into drugs that may become a real future perspective. To our knowledge, this review is the first effort to deal with the total synthesis of these active fungi metabolites and demonstrates that total chemical synthesis is a fruitful means of yielding fungal derivatives as aided by recent technological and innovative advancements. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  14. Metabolic profiling of murine plasma reveals eicosapentaenoic acid metabolites protecting against endothelial activation and atherosclerosis.

    PubMed

    Liu, Yajin; Fang, Xuan; Zhang, Xu; Huang, Jing; He, Jinlong; Peng, Liyuan; Ye, Chenji; Wang, Yingmei; Xue, Fengxia; Ai, Ding; Li, Dan; Zhu, Yi

    2018-04-01

    Atherosclerosis results from a maladaptive inflammatory response initiated by the intramural retention of LDL in susceptible areas of the arterial vasculature. The ω-3 polyunsaturated fatty acids (ω-3) have protective effects in atherosclerosis; however, their molecular mechanism is still largely unknown. The present study used a metabolomic approach to reveal the atheroprotective metabolites of ω-3 and investigate the underlying mechanisms. We evaluated the development of atherosclerosis in LDL receptor-deficient mice (LDLR -/- ) fed a Western-type diet (WTD) plus ω-3 and also LDLR -/- and fat-1 transgenic (LDLR -/- -fat-1 tg ) mice fed a WTD. The profiles of ω-3 in the plasma were screened by LC-MS/MS using unbiased systematic metabolomics analysis. We also studied the effect of metabolites of eicosapentaenoic acid (EPA) on endothelial activation in vitro. The ω-3 diet and fat-1 transgene decreased monocyte infiltration, inhibited the expression of pro-inflammatory genes and significantly attenuated atherosclerotic plaque formation and enhanced plaque stability in LDLR -/- mice. The content of 18-hydroxy-eicosapentaenoic acid (18-HEPE) and 17,18-epoxy-eicosatetraenoic acid (17,18-EEQ), from the cytochrome P450 pathway of EPA, was significantly higher in plasma from both ω-3-treated LDLR -/- and LDLR -/- -fat-1 tg mice as compared with WTD-fed LDLR -/- mice. In vitro in endothelial cells, 18-HEPE or 17,18-EEQ decreased inflammatory gene expression induced by TNFα via NF-κB signalling and thereby inhibited monocyte adhesion to endothelial cells. EPA protected against the development of atherosclerosis in atheroprone mice via the metabolites 18-HEPE and/or 17,18-EEQ, which reduced endothelial activation. These compounds may have therapeutic implications in atherosclerosis. This article is part of a themed section on Spotlight on Small Molecules in Cardiovascular Diseases. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10

  15. Biotransformation of plant secondary metabolite decursin by Mycobacterium sp. PYR1001.

    PubMed

    Kim, Ki-Yeon; Lee, Sanghyun; Cha, Chang-Jun

    2010-03-10

    Decursin and its structural isomer decursinol angelate are major secondary metabolites in the root of Angelica gigas Nakai which possess several chemotherapeutic properties. We isolated bacteria capable of transforming decursin and determined metabolites and biotransformation kinetics. Decursinol angelate was not metabolized to any significant extent. Resting cells of Mycobacterium sp. PYR1001 were able to transform decursin. After 24 h incubation, 5 mM of decursin was completely transformed to a metabolite, the structure of which was determined by NMR and mass spectral analyses to be decursinol. This conversion was shown to be catalyzed by an esterase activity, and the activity was found to be specific for decursin. These results suggest that strain PYR1001 can be successfully used to transform decursin for the production of decursinol, a compound known to have cancer chemopreventive activity.

  16. Major bioactive metabolites from marine fungi: A Review.

    PubMed

    Hasan, Saba; Ansari, Mohammad Israil; Ahmad, Anis; Mishra, Maitreyi

    2015-01-01

    Biologists and chemists of the world have been attracted towards marine natural products for the last five decades. Approximately 16,000 marine natural products have been isolated from marine organisms which have been reported in approximately 6,800 publications, proving marine microorganisms to be a invaluable source for the production of novel antibiotic, anti tumor, and anti inflammatory agents. The marine fungi particularly those associated with marine alga, sponge, invertebrates, and sediments appear to be a rich source for secondary metabolites, possessing Antibiotic, antiviral, antifungal and antiyeast activities. Besides, a few growth stimulant properties which may be useful in studies on wound healing, carcinogenic properties, and in the study of cancers are reported. Recent investigations on marine filamentous fungi looking for biologically active secondary metabolites indicate the tremendous potential of them as a source of new medicines. The present study reviews about some important bioactive metabolites reported from marine fungal strains which are anti bacterial, anti tumour and anti inflammatory in action. It highlights the chemistry and biological activity of the major bioactive alkaloids, polyketides, terpenoids, isoprenoid and non-isoprenoid compounds, quinones, isolated from marine fungi.

  17. Urinary pesticide metabolites in school students from northern Thailand.

    PubMed

    Panuwet, Parinya; Prapamontol, Tippawan; Chantara, Somporn; Barr, Dana B

    2009-05-01

    We evaluated exposure to pesticides among secondary school students aged 12-13 years old in Chiang Mai Province, Thailand. Pesticide-specific urinary metabolites were used as biomarkers of exposure for a variety of pesticides, including organophosphorus insecticides, synthetic pyrethroid insecticides and selected herbicides. We employed a simple solid-phase extraction with analysis using isotope dilution high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS). A total of 207 urine samples from Thai students were analyzed for 18 specific pesticide metabolites. We found 14 metabolites in the urine samples tested; seven of them were detected with a frequency > or=17%. The most frequently detected metabolites were 2-[(dimethoxyphosphorothioyl) sulfanyl] succinic acid (malathion dicarboxylic acid), para-nitrophenol (PNP), 3,5,6-trichloro-2-pyridinol (TPCY; metabolite of chlorpyrifos), 2,4-dichlorophenoxyacetic acid (2,4-D), cis- and trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane-1-carboxylic acids (c-DCCA and t-DCCA; metabolite of permethrin) and 3-phenoxybenzoic acid (3-PBA; metabolite of pyrethroids). The students were classified into 4 groups according to their parental occupations: farmers (N=60), merchants and traders (N=39), government and company employees (N=52), and laborers (N=56). Children of farmers had significantly higher urinary concentrations of pyrethroid insecticide metabolites than did other children (p<0.05). Similarly, children of agricultural families had significantly higher pyrethroid metabolite concentrations. Males had significantly higher values of PNP (Mann-Whitney test, p=0.009); however, no other sex-related differences were observed. Because parental occupation and agricultural activities seemed to have little influence on pesticide levels, dietary sources were the likely contributors to the metabolite levels observed.

  18. A modular modulation method for achieving increases in metabolite production.

    PubMed

    Acerenza, Luis; Monzon, Pablo; Ortega, Fernando

    2015-01-01

    Increasing the production of overproducing strains represents a great challenge. Here, we develop a modular modulation method to determine the key steps for genetic manipulation to increase metabolite production. The method consists of three steps: (i) modularization of the metabolic network into two modules connected by linking metabolites, (ii) change in the activity of the modules using auxiliary rates producing or consuming the linking metabolites in appropriate proportions and (iii) determination of the key modules and steps to increase production. The mathematical formulation of the method in matrix form shows that it may be applied to metabolic networks of any structure and size, with reactions showing any kind of rate laws. The results are valid for any type of conservation relationships in the metabolite concentrations or interactions between modules. The activity of the module may, in principle, be changed by any large factor. The method may be applied recursively or combined with other methods devised to perform fine searches in smaller regions. In practice, it is implemented by integrating to the producer strain heterologous reactions or synthetic pathways producing or consuming the linking metabolites. The new procedure may contribute to develop metabolic engineering into a more systematic practice. © 2015 American Institute of Chemical Engineers.

  19. In vitro activity of solithromycin and its metabolites, CEM-214 and N-acetyl-CEM-101, against 100 clinical Ureaplasma spp. isolates compared with azithromycin.

    PubMed

    Furfaro, Lucy L; Spiller, O Brad; Keelan, Jeffrey A; Payne, Matthew S

    2015-09-01

    There is a strong association between vaginal and/or amniotic fluid Ureaplasma spp. colonisation and risk of preterm birth. The novel fluoroketolide antibiotic solithromycin (CEM-101) is active against Ureaplasma spp. in vitro. Evidence from ex vivo and in vivo models suggests that, unlike most macrolide antibiotics, solithromycin readily crosses the placenta. Solithromycin metabolism varies according to species; in pregnant sheep, the bioactive metabolites CEM-214 and N-acetyl-CEM-101 (NAc-CEM-101) have been shown to accumulate in the amniotic cavity following maternal solithromycin administration, potentially contributing to its antimicrobial effects. To determine the antimicrobial activity of these metabolites against Ureaplasma spp., the effects of solithromycin, CEM-214, NAc-CEM-101 and the comparator azithromycin were tested on a collection of 100 clinical Ureaplasma spp. isolates from the UK and Australia using a modified 96-well broth microdilution method. MIC90 values observed for the combined cohort were: solithromycin, 0.125 mg/L; CEM-214, 0.5mg/L; NAc-CEM-101, 0.5mg/L; and azithromycin, 2mg/L. Solithromycin showed 34-fold greater activity against Ureaplasma spp. isolates than azithromycin, whilst CEM-214 and NAc-CEM-101 possessed ca. 22% and 17% of the activity of solithromycin, respectively, significantly greater than that of azithromycin. One bacterial isolate showed resistance to azithromycin (MIC=16 mg/L) but had a much lower MIC for solithromycin (MIC=0.25mg/L). In conclusion, the metabolites of solithromycin had reduced, but still potent, activity against 100 clinical Ureaplasma spp. isolates in vitro. This may be important in some instances such as pregnancy, however studies to determine levels of the metabolites in these settings are required. Copyright © 2015 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

  20. In vitro anti-influenza viral activities of constituents from Caesalpinia sappan.

    PubMed

    Liu, Ai-Lin; Shu, Shi-Hui; Qin, Hai-Lin; Lee, Simon Ming Yuen; Wang, Yi-Tao; Du, Guan-Hua

    2009-03-01

    Six constituents with neuraminidase (NA) inhibitory activity, namely brazilein, brazilin, protosappanin A, 3-deoxysappanchalcone, sappanchalcone and rhamnetin, were isolated from the hearthwood of Caesalpinia sappan (Leguminosae). Their in vitro anti-influenza virus activities were evaluated with the cytopathic effect (CPE) reduction method. The results showed that 3-deoxysappanchalcone and sappanchalcone exhibited the highest activity against influenza virus (H3N2) with IC50 values of 1.06 and 2.06 microg/mL, respectively, in comparison to the positive control oseltamivir acid and ribavirin with IC50 values of 0.065 and 9.17 microg/mL, respectively.

  1. Construction of a metagenomic DNA library of sponge symbionts and screening of antibacterial metabolites

    NASA Astrophysics Data System (ADS)

    Chen, Juan; Zhu, Tianjiao; Li, Dehai; Cui, Chengbin; Fang, Yuchun; Liu, Hongbing; Liu, Peipei; Gu, Qianqun; Zhu, Weiming

    2006-04-01

    To study the bioactive metabolites produced by sponge-derived uncultured symbionts, a metagenomic DNA library of the symbionts of sponge Gelliodes gracilis was constructed. The average size of DNA inserts in the library was 20 kb. This library was screened for antibiotic activity using paper dise assaying. Two clones displayed the antibacterial activity against Micrococcus tetragenus. The metabolites of these two clones were analyzed through HPLC. The result showed that their metabolites were quite different from those of the host E. coli DH5α and the host containing vector pHZ132. This study may present a new approach to exploring bioactive metabolites of sponge symbionts.

  2. Identification of human cell responses to benzene and benzene metabolites.

    PubMed

    Gillis, Bruce; Gavin, Igor M; Arbieva, Zarema; King, Stephen T; Jayaraman, Sundararajan; Prabhakar, Bellur S

    2007-09-01

    Benzene is a common air pollutant and confirmed carcinogen, especially in reference to the hematopoietic system. In the present study we analyzed cytokine/chemokine production by, and gene expression induction in, human peripheral blood mononuclear cells upon their exposure to the benzene metabolites catechol, hydroquinone, 1,2,4-benzenetriol, and p-benzoquinone. Protein profiling showed that benzene metabolites can stimulate the production of chemokines, the proinflammatory cytokines TNF-alpha and IL-6, and the Th2 cytokines IL-4 and IL-5. Activated cells showed concurrent suppression of anti-inflammatory cytokine IL-10 expression. We also identified changes in global gene expression patterns in response to benzene metabolite challenges by using high-density oligonucleotide microarrays. Treatment with 1,2,4-benzenetriol resulted in the suppression of genes related to the regulation of protein expression and a concomitant activation of genes that encode heat shock proteins and cytochrome P450 family members. Protein and gene expression profiling identified unique human cellular responses upon exposure to benzene and benzene metabolites.

  3. Raman spectroscopy applied to identify metabolites in urine of physically active subjects.

    PubMed

    Moreira, Letícia Parada; Silveira, Landulfo; da Silva, Alexandre Galvão; Fernandes, Adriana Barrinha; Pacheco, Marcos Tadeu Tavares; Rocco, Débora Dias Ferraretto Moura

    2017-11-01

    Raman spectroscopy is a rapid and non-destructive technique suitable for biological fluids analysis. In this work, dispersive Raman spectroscopy has been employed as a rapid and nondestructive technique to detect the metabolites in urine of physically active subjects before and after vigorous 30min pedaling or running compared to sedentary subjects. For so, urine samples from 9 subjects were obtained before and immediately after physical activities and submitted to Raman spectroscopy (830nm excitation, 250mW laser power, 20s integration time) and compared to urine from 5 sedentary subjects. The Raman spectra of urine from sedentary showed peaks related to urea, creatinine, ketone bodies, phosphate and other nitrogenous compounds. These metabolic biomarkers presented peaks with different intensities in the urine of physically active individuals after exercises compared to before, measured by the intensity of selected peaks the Raman spectra, which means different concentrations after training. These peaks presented different intensity values for each subject before physical activity, also behaving differently compared to the post-training: some subjects presented increase while others decrease the intensity. Raman spectroscopy may allow the development of a rapid and non-destructive test for metabolic evaluation of the physical training in active and trained subjects using urine samples, allowing nutrition adjustment with the sport's performance. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Tamoxifen metabolite isomer separation and quantification by liquid chromatography-tandem mass spectrometry.

    PubMed

    Jaremko, Malgorzata; Kasai, Yumi; Barginear, Myra F; Raptis, George; Desnick, Robert J; Yu, Chunli

    2010-12-15

    Tamoxifen (Tam), the antiestrogen used to treat estrogen receptor-positive breast cancer is a pro-drug that is converted to its major active metabolites, endoxifen and 4-hydroxy-tamoxifen (4-OH-Tam) by various biotransformation enzymes of which cytochrome P450-2D6 (CYP2D6) is key. The usual Tam dose is 20 mg daily; however, the plasma active metabolite concentrations vary due to common genetic variants encoding the biotransformation enzymes and environmental factors (e.g., concomitant drugs) that inhibit these enzymes. Effective treatment depends on adequate Tam conversion to its active isomers. To monitor metabolite plasma levels, a novel liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed to separate and quantitate Tam, N-desmethyl-tamoxifen (ND-Tam), and tamoxifen-N-oxide (Tam-N-oxide), and the E, Z, and Z' isomers of endoxifen and 4-OH-Tam. Known standards were used to identify each metabolite/isomer. Quantitation of these metabolites in plasma was linear from 0.6 to 2000 nM. Intra- and inter-assay reproducibilities were 0.2-8.4% and 0.6-6.3%, respectively. Accuracy determined by spike experiments with known standards was 86-103%. Endoxifen, 4-OH-Tam, and their isomers were stable in fresh frozen plasma for ≥6 months. This method provides the first sensitive, specific, accurate, and reproducible quantitation of Tam and its metabolite isomers for monitoring Tam-treated breast cancer patients.

  5. Antibacterial metabolites synthesized by psychrotrophic bacteria isolated from cold-freshwater environments.

    PubMed

    Barros, Javier; Becerra, José; González, Carlos; Martínez, Miguel

    2013-03-01

    The ability of three psychrotrophic Gram-negative bacilli isolated from Chilean Patagonian cold freshwater rivers to produce bioactive metabolites was evaluated. The strains were isolated from cold waters rivers and identified by their biochemical properties and 16S rRNA gene analysis. The metabolites fractions showing antibacterial activity were obtained by solvent extraction and partially characterized by gas-mass chromatography (GC-MS). Antibacterial activity of the fractions was evaluated by an agar-well diffusion test upon 14 bacterial strains, both Gram positive and Gram negative. Thermal and proteolytic resistances of the antibacterial metabolites fractions were also evaluated. Molecular analysis allows the identification of the three Patagonian strains as Pseudomonas sp. RG-6 (Pseudomonas brenneri 99.6 % identity), Pseudomonas sp. RG-8 (Pseudomonas trivialis 99.6 % identity) and Yersinia sp. RP-3 (Yersinia aldovae 99.5 % identity). These extracts were able to inhibit both Gram-positive and Gram-negative bacteria but not Listeria monocytogenes. The antibacterial activity of the filtrated supernatants was lost at temperatures ≥60 °C, and was not affected by proteinase K treatment. The chemical structure of the active molecule remains to be elucidated, although the GC-MS analysis of the filtrates suggests that compounds like sesquiterpenes derivatives from β-maaliene or δ-selinene could be responsible of this antibacterial activity. Pristine cold freshwater streams showed to be interesting sources of metabolites-producing microorganisms with antibacterial activity.

  6. In vitro fermentation of prebiotics by Lactobacillus plantarum CFR 2194: selectivity, viability and effect of metabolites on β-glucuronidase activity.

    PubMed

    Arenahalli Ningegowda, Madhu; Siddalingaiya Gurudutt, Prapulla

    2012-03-01

    Prebiotic Fructooligosaccharides (FOS) escape metabolism in upper GI tract undergo microbial metabolism in colon and thereby influence the nature, type and number of intestinal microbiota to improve host's health. The present study focuses on the ability of Lactobacillus plantarum CFR 2194 to utilize FOS as a selective carbon and energy source. The effect of fermentative metabolites of L. plantarum on the β-glucuronidase was also investigated. A total of 16 strains of lactobacilli were assessed for their ability to ferment oligosaccharides. L. plantarum CFR 2194, an isolate from kanjika was found to utilize FOS effectively. Lactic acid was the main metabolic end product, followed by acetic acid, butyric acid, formic acid and ethanol. The inhibitory effects of these metabolites have been confirmed through the reduction of β-glucuronidase activity. L. plantarum when co-cultured with β-glucuronidase producing E. coli, in a basal media containing FOS as an energy source, could inhibit the growth of the pathogen during the course of fermentation. The results showed that L. plantarum CFR 2194 has the ability to utilize the prebiotic FOS as a selective carbon and energy source. The organism could inhibit the growth of the pathogen which produces β-glucuronidase and lowered its activity by the metabolites of FOS which indicates the probable use of L. plantarum through dietary intervention in combating colon carcinogenesis.

  7. Secondary metabolites of Centaurea calolepis and evaluation of cnicin for anti-inflammatory, antioxidant, and cytotoxic activities.

    PubMed

    Erel, Sura Baykan; Karaalp, Canan; Bedir, Erdal; Kaehlig, Hanspeter; Glasl, Sabine; Khan, Shabana; Krenn, Liselotte

    2011-08-01

    Centaurea L. (Astreaceae) species are used as herbal remedies in Turkey. Centaurea calolepis Boiss. is an endemic species of Anatolia that has not been subjected to phytochemical studies except essential oil analysis. Secondary metabolite determination, isolation and structure elucidation of pure compounds were performed on C. calolepis. Cnicin, which is the main component of several Centaurea species, was tested for its in vitro anti-inflammatory, antioxidant and cytotoxic activities. Chloroform and methanol extracts of the aerial parts of C. calolepis were subjected to isolation process using column chromatography. The structures of the compounds were characterized by 1D- and 2D-NMR experiments. Thin-layer chromatography and high performance liquid chromatography were used in determination of phenolics. Cnicin was subjected to a panel of cellular assays to test for inhibition of nuclear factor κB (NF-κB), inducible nitric oxide synthase (iNOS), reactive oxygen species and cytotoxicity. Cnicin, lucenin-2, schaftoside and 3-O-feruloylquinic acid were isolated from C. calolepis extracts. Vicenin-2, vitexin, isovitexin, homoorientin, rutin, orientin, luteolin-7-O-glycoside and chlorogenic acid were determined in fractions. Cnicin showed inhibition of NF-κB and inhibition of iNOS activity with IC₅₀ Values of 1.8 and 6.5 µM, respectively. Cytotoxic activity of cnicin was observed toward pig kidney epithelial (LLC-PK₁₁), human malignant melanoma (SK-MEL) and human ductal carcinoma (BT-549) cells with IC₅₀ values of 23.3, 14.0 and 18.3 µM, respectively. This is the first detailed report of secondary metabolites of C. calolepis. Evaluation of biological activity of cnicin establishes the potential of this compound as an anti-inflammatory and cytotoxic agent.

  8. Pleiotropic mechanisms facilitated by resveratrol and its metabolites

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

    Calamini, Barbara; Ratia, Kiira; Malkowski, Michael G.

    2010-07-01

    Resveratrol has demonstrated cancer chemopreventive activity in animal models and some clinical trials are underway. In addition, resveratrol was shown to promote cell survival, increase lifespan and mimic caloric restriction, thereby improving health and survival of mice on high-calorie diet. All of these effects are potentially mediated by the pleiotropic interactions of resveratrol with different enzyme targets including COX-1 (cyclo-oxygenase-1) and COX-2, NAD{sup +}-dependent histone deacetylase SIRT1 (sirtuin 1) and QR2 (quinone reductase 2). Nonetheless, the health benefits elicited by resveratrol as a direct result of these interactions with molecular targets have been questioned, since it is rapidly and extensivelymore » metabolized to sulfate and glucuronide conjugates, resulting in low plasma concentrations. To help resolve these issues, we tested the ability of resveratrol and its metabolites to modulate the function of some known targets in vitro. In the present study, we have shown that COX-1, COX-2 and QR2 are potently inhibited by resveratrol, and that COX-1 and COX-2 are also inhibited by the resveratrol 4{prime}-O-sulfate metabolite. We determined the X-ray structure of resveratrol bound to COX-1 and demonstrate that it occupies the COX active site similar to other NSAIDs (non-steroidal anti-inflammatory drugs). Finally, we have observed that resveratrol 3- and 4?-O-sulfate metabolites activate SIRT1 equipotently to resveratrol, but that activation is probably a substrate-dependent phenomenon with little in vivo relevance. Overall, the results of this study suggest that in vivo an interplay between resveratrol and its metabolites with different molecular targets may be responsible for the overall beneficial health effects previously attributed only to resveratrol itself.« less

  9. Secondary Metabolites from Marine Microorganisms. II. Marine Fungi and Their Habitats.

    PubMed

    Orlova, T I; Bulgakova, V G; Polin, A N

    Marine-derived fungi are of great interest as a new promising source of biologically active products such as anticancer compounds, antibiotics, inhibitors of biochemical processes. Since marine organisms inhabit biologically competitive environment with unique conditions, the chemical diversity of the secondary metabolites from marine fungi is considerably high. Recent genomic studies demonstrated that fungi can carry gene clasters encoding production of previously unknown secondary metabolites. Activation of the attenuated or silent genes would be useful either for improving activities of the known compounds or for discovery of new products.

  10. Lymphoid organs of neonatal and adult mice preferentially produce active glucocorticoids from metabolites, not precursors.

    PubMed

    Taves, Matthew D; Plumb, Adam W; Korol, Anastasia M; Van Der Gugten, Jessica Grace; Holmes, Daniel T; Abraham, Ninan; Soma, Kiran K

    2016-10-01

    Glucocorticoids (GCs) are circulating adrenal steroid hormones that coordinate physiology, especially the counter-regulatory response to stressors. While systemic GCs are often considered immunosuppressive, GCs in the thymus play a critical role in antigen-specific immunity by ensuring the selection of competent T cells. Elevated thymus-specific GC levels are thought to occur by local synthesis, but the mechanism of such tissue-specific GC production remains unknown. Here, we found metyrapone-blockable GC production in neonatal and adult bone marrow, spleen, and thymus of C57BL/6 mice. This production was primarily via regeneration of adrenal metabolites, rather than de novo synthesis from cholesterol, as we found high levels of gene expression and activity of the GC-regenerating enzyme 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1), but not the GC-synthetic enzyme CYP11B1. Furthermore, incubation with physiological concentrations of GC metabolites (11-dehydrocorticosterone, prednisone) induced 11β-HSD1- and GC receptor-dependent apoptosis (caspase activation) in both T and B cells, showing the functional relevance of local GC regeneration in lymphocyte GC signaling. Local GC production in bone marrow and spleen raises the possibility that GCs play a key role in B cell selection similar to their role in T cell selection. Our results also indicate that local GC production may amplify changes in adrenal GC signaling, rather than buffering against such changes, in the immune system. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Biotechnological and industrial significance of cyanobacterial secondary metabolites.

    PubMed

    Rastogi, Rajesh P; Sinha, Rajeshwar P

    2009-01-01

    Cyanobacteria are considered to be a rich source of novel metabolites of a great importance from a biotechnological and industrial point of view. Some cyanobacterial secondary metabolites (CSMs), exhibit toxic effects on living organisms. A diverse range of these cyanotoxins may have ecological roles as allelochemicals, and could be employed for the commercial development of compounds with applications such as algaecides, herbicides and insecticides. Recently, cyanobacteria have become an attractive source of innovative classes of pharmacologically active compounds showing interesting and exciting biological activities ranging from antibiotics, immunosuppressant, and anticancer, antiviral, antiinflammatory to proteinase-inhibiting agents. A different but not less interesting property of these microorganisms is their capacity of overcoming the toxicity of ultraviolet radiation (UVR) by means of UV-absorbing/screening compounds, such as mycosporine-like amino acids (MAAs) and scytonemin. These last two compounds are true 'multipurpose' secondary metabolites and considered to be natural photoprotectants. In this sense, they may be biotechnologically exploited by the cosmetic industry. Overall CSMs are striking targets in biotechnology and biomedical research, because of their potential applications in agriculture, industry, and especially in pharmaceuticals.

  12. [Antioxidative activities of two metabolites of cultured marine fungus, Halorosellinia oceanicum 323 in vitro].

    PubMed

    Luo, Jinghui; Yang, Yingbao; Lin, Yongcheng; Chen, Zhiliang; Jiang, Guangce

    2004-03-01

    To investigate the antioxidative effects of 323-A and 323-B, two isomers extracted from the metabolites of cultured marine fungus, Halorosellinia oceanicum 323 in vitro. NADH-PMS-NBT system was used to produce superoxide free radical (O2*-), EDTANa2-Fe(II)-H2O2 system to generate hydroxyl free radical (*OH), H2O2 to stimulate oxidative hemolysis of erythrocytes of rats, Cys-Fe2+ to induce malondialdehyde (MDA) production in homogenates, and ferrous-ascorbic acid system to increase the turbidity of mitochondria suspension in the liver of rats. And the antioxidative activities of 323-A and 323-B were studied. 323-A and 323-B not only scavenge O2*- and *OH produced by the experimental systems directly, but also inhibit H2O2 stimulated oxidative hemolysis of erythrocytes of rats, depress MDA production in homogenates induced by Cys-Fe2+ system, and reduce the turbidity of mitochondria suspension in the liver of rats increased by ferrous-ascorbic acid system in vitro. 323-A and 323-B showed comprehensive cleaning actions on free radicals and protective effects on the functions of tissues and cells against oxidative lesion. The results suggested that the marine microorganic metabolites might be a novel and profound source of antioxidative reagents.

  13. Different profiles of quercetin metabolites in rat plasma: comparison of two administration methods.

    PubMed

    Kawai, Yoshichika; Saito, Satomi; Nishikawa, Tomomi; Ishisaka, Akari; Murota, Kaeko; Terao, Junji

    2009-03-23

    The bioavailability of polyphenols in human and rodents has been discussed regarding their biological activity. We found different metabolite profiles of quercetin in rat plasma between two administration procedures. A single intragastric administration (50 mg/kg) resulted in the appearance of a variety of metabolites in the plasma, whereas only a major fraction was detected by free access (1% quercetin). The methylated/non-methylated metabolites ratio was much higher in the free access group. Mass spectrometric analyses showed that the fraction from free access contained highly conjugated quercetin metabolites such as sulfo-glucuronides of quercetin and methylquercetin. The metabolite profile of human plasma after an intake of onion was similar to that with intragastric administration in rats. In vitro oxidation of human low-density lipoprotein showed that methylation of the catechol moiety of quercetin significantly attenuated the antioxidative activity. These results might provide information about the bioavailability of quercetin when conducting animal experiments.

  14. Secondary metabolites from Sida rhombifolia L. (Malvaceae) and the vasorelaxant activity of cryptolepinone.

    PubMed

    Chaves, Otemberg Souza; Gomes, Roosevelt Albuquerque; Tomaz, Anna Cláudia de Andrade; Fernandes, Marianne Guedes; das Graças Mendes, Leônidas; de Fátima Agra, Maria; Braga, Valdir Andrade; de Fátima Vanderlei de Souza, Maria

    2013-03-01

    The phytochemical study of Sida rhombifolia L. (Malvaceae) led to the isolation through chromatographic techniques of eleven secondary metabolites: sitosterol (1a) and stigmasterol (1b), sitosterol-3-O-b-D-glucopyranoside (2a) and stigmasterol-3-O-b-D-glucopyranoside (2b), phaeophytin A (3), 17³-ethoxypheophorbide A (4), 13²-hydroxy phaeophytin B (5), 17³-ethoxypheophorbide B (6), 5,7-dihydroxy-4'-methoxyflavone (7), cryptolepinone (8) and a salt of cryptolepine (9). Their structures were identified by ¹H- and ¹³C-NMR using one- and two-dimensional techniques. In addition, the vasorelaxant activity of cryptolepinone in rat mesenteric artery rings is reported herein for the first time.

  15. Secondary metabolites from marine-derived microorganisms.

    PubMed

    Chen, Gang; Wang, Hai-Feng; Pei, Yue-Hu

    2014-01-01

    In the search for novel and bioactive molecules for drug discovery, marine-derived natural resources, especially marine microorganisms are becoming an important and interesting research area. This study covers the literature published after 2008 on secondary metabolites of marine-derived microorganisms. The emphasis was on new compounds with the relevant biological activities, strain information, and country of origin. New compounds without biological activity were not included.

  16. Effects of atorvastatin metabolites on induction of drug-metabolizing enzymes and membrane transporters through human pregnane X receptor

    PubMed Central

    Hoffart, E; Ghebreghiorghis, L; Nussler, AK; Thasler, WE; Weiss, TS; Schwab, M; Burk, O

    2012-01-01

    BACKGROUND AND PURPOSE Atorvastatin metabolites differ in their potential for drug interaction because of differential inhibition of drug-metabolizing enzymes and transporters. We here investigate whether they exert differential effects on the induction of these genes via activation of pregnane X receptor (PXR) and constitutive androstane receptor (CAR). EXPERIMENTAL APPROACH Ligand binding to PXR or CAR was analysed by mammalian two-hybrid assembly and promoter/reporter gene assays. Additionally, surface plasmon resonance was used to analyse ligand binding to CAR. Primary human hepatocytes were treated with atorvastatin metabolites, and mRNA and protein expression of PXR-regulated genes was measured. Two-hybrid co-activator interaction and co-repressor release assays were utilized to elucidate the molecular mechanism of PXR activation. KEY RESULTS All atorvastatin metabolites induced the assembly of PXR and activated CYP3A4 promoter activity. Ligand binding to CAR could not be proven. In primary human hepatocytes, the para-hydroxy metabolite markedly reduced or abolished induction of cytochrome P450 and transporter genes. While significant differences in co-activator recruitment were not observed, para-hydroxy atorvastatin demonstrated only 50% release of co-repressors. CONCLUSIONS AND IMPLICATIONS Atorvastatin metabolites are ligands of PXR but not of CAR. Atorvastatin metabolites demonstrate differential induction of PXR target genes, which results from impaired release of co-repressors. Consequently, the properties of drug metabolites have to be taken into account when analysing PXR-dependent induction of drug metabolism and transport. The drug interaction potential of the active metabolite, para-hydroxy atorvastatin, might be lower than that of the parent compound. PMID:21913896

  17. Oseltamivir phosphate monotherapy ablates tumor neovascularization, growth, and metastasis in mouse model of human triple-negative breast adenocarcinoma

    PubMed Central

    Haxho, Fiona; Allison, Stephanie; Alghamdi, Farah; Brodhagen, Lacey; Kuta, Victoria EL; Abdulkhalek, Samar; Neufeld, Ronald J; Szewczuk, Myron R

    2014-01-01

    Background Triple-negative breast cancers (TNBCs) lack the estrogen, progesterone, and epidermal growth factor (EGF) receptor-2 (HER2/neu) receptors. Patients with TNBC have typical high grading, more frequent relapses, and exhibit poorer outcomes or prognosis compared with the other subtypes of breast cancers. Currently, there are no targeted therapies that are effective for TNBC. Preclinical antitumor activity of oseltamivir phosphate (OP) therapy was investigated to identify its role in tumor neovascularization, growth, invasiveness, and long-term survival in a mouse model of human TNBC. Methods Live cell sialidase, water soluble tetrazolium, WST-1 cell viability, and immunohistochemistry assays were used to evaluate sialidase activity, cell survival, and the expression levels of tumor E-cadherin, N-cadherin, and host endothelial CD31+/PECAM-1 cells in archived paraffin-embedded TNBC MDA-MB-231 tumors grown in RAGxCγ double mutant mice. Results OP, anti-Neu1 antibodies, and matrix metalloproteinase-9-specific inhibitor blocked Neu1 activity associated with EGF-stimulated TNBC MDA-MB-231 cells. OP treatment of MDA-MB-231 and MCF-7 cells and their long-term tamoxifen-resistant clones reproducibly and dose-dependently reduced the sialidase activity associated with EGF-stimulated live cells and the cell viability after 72 hours of incubation. Combination of 1 μM cisplatin, 5-FU, paclitaxel, gemcitabine, or tamoxifen with OP dosages ≥300 μg/mL significantly reduced cell viability at 24, 48, and 72 hours when compared to the chemodrug alone. Heterotopic xenografts of MDA-MB-231 tumors developed robust and bloody tumor vascularization in RAG2xCγ double mutant mice. OP treatment at 30 mg/kg daily intraperitoneally reduced tumor vascularization and growth rate as well as significantly reduced tumor weight and spread to the lungs compared with the untreated cohorts. OP treatment at 50 mg/kg completely ablated tumor vascularization, tumor growth and spread to the

  18. Spectrofluorimetric determination of 3-methylflavone-8-carboxylic acid, the main active metabolite of flavoxate hydrochloride in human urine.

    PubMed

    Zaazaa, Hala E; Mohamed, Afaf O; Hawwam, Maha A; Abdelkawy, Mohamed

    2015-01-05

    A simple, sensitive and selective spectrofluorimetric method has been developed for the determination of 3-methylflavone-8-carboxylic acid as the main active metabolite of flavoxate hydrochloride in human urine. The proposed method was based on the measurement of the native fluorescence of the metabolite in methanol at an emission wavelength 390 nm, upon excitation at 338 nm. Moreover, the urinary excretion pattern has been calculated using the proposed method. Taking the advantage that 3-methylflavone-8-carboxylic acid is also the alkaline degradate, the proposed method was applied to in vitro determination of flavoxate hydrochloride in tablets dosage form via the measurement of its corresponding degradate. The method was validated in accordance with the ICH requirements and statistically compared to the official method with no significant difference in performance. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Activation of the Sigma-1 receptor by haloperidol metabolites facilitates brain-derived neurotrophic factor secretion from human astroglia

    PubMed Central

    Dalwadi, Dhwanil A.; Kim, Seongcheol; Schetz, John A.

    2017-01-01

    Glial cells play a critical role in neuronal support which includes the production and release of the neurotrophin brain-derived neurotrophic factor (BDNF). Activation of the sigma-1 receptor (S1R) has been shown to attenuate inflammatory stress-mediated brain injuries, and there is emerging evidence that this may involve a BDNF-dependent mechanism. In this report we studied S1R-mediated BDNF release from human astrocytic glial cells. Astrocytes express the S1R, which mediates BDNF release when stimulated with the prototypical S1R agonists 4-PPBP and (+)-SKF10047. This effect could be antagonized by a selective concentration of the S1R antagonist BD1063. Haloperidol is known to have high affinity interactions with the S1R, yet it was unable to facilitate BDNF release. Remarkably, however, two metabolites of haloperidol, haloperidol I and haloperidol II (reduced haloperidol), were discovered to facilitate BDNF secretion and this effect was antagonized by BD1063. Neither 4-PPBP, nor either of the haloperidol metabolites affected the level of BDNF mRNA as assessed by qPCR. These results demonstrate for the first time that haloperidol metabolites I and II facilitate the secretion of BDNF from astrocytes by acting as functionally selective S1R agonists. PMID:28188803

  20. In vitro antimicrobial activities of metabolites from vaginal Lactobacillus strains against Clostridium perfringens isolated from a woman's vagina.

    PubMed

    Amin, Mansour; Moradi Choghakabodi, Parastoo; Alhassan Hamidi, Mohammad; Najafian, Mahin; Farajzadeh Sheikh, Ahmad

    2017-01-01

    More than 50 different species of bacteria may live in a woman's vagina, with lactobacilli being the predominant microorganism found in healthy adult females. Lactobacilli are relevant as a barrier to infection and are important in the impairment of colonization by pathogens, owing to competitive adherence to adhesion sites in the vaginal epithelium and their capacity to produce antimicrobial compounds. The aim of the present study was to demonstrate the inhibitory capability of Lactobacillus metabolites against Clostridium perfringens, an anaerobic Gram-positive bacterium. These bacteria were isolated from vaginal swabs by using culture-dependent approaches, and the bacteriostatic effect of Lactobacillus metabolites, extracted from different isolates, was assessed using a modified E test. Among the 100 vaginal swabs, 59 (59%) samples showed the presence of Lactobacillus strains and only one sample contained C. perfringens. Lactobacillus metabolites demonstrated the significant potency of in vitro activity against C. perfringens, with minimal inhibitory concentration values ranging from 15.6 μg/mL to 31.2 μg/mL. This study suggests that women without vaginal Lactobacillus strains may be susceptible to nonindigenous and potentially harmful microorganisms. Copyright © 2016. Published by Elsevier Taiwan LLC.

  1. Determination of antifungal activities in serum samples from mice treated with different antifungal drugs allows detection of an active metabolite of itraconazole.

    PubMed

    Maki, Katsuyuki; Watabe, Etsuko; Iguchi, Yumi; Nakamura, Hideko; Tomishima, Masaki; Ohki, Hidenori; Yamada, Akira; Matsumoto, Satoru; Ikeda, Fumiaki; Tawara, Shuichi; Mutoh, Seitaro

    2006-01-01

    To establish an in vitro method of predicting in vivo efficacy of antifungal drugs against Candida albicans and Aspergillus fumigatus, the antifungal activities of fluconazole, itraconazole, and amphotericin B were determined in mouse serum. The minimum inhibitory concentration (MIC) of each drug was measured using mouse serum as a diluent. For C. albicans, the assay endpoint of azoles was defined as inhibition of mycelial extension (mMIC) and for A. fumigatus, as no growth (MIC). The MICs of amphotericin B for both pathogens were defined as the MIC at which no mycelial growth occurred. Serum MIC or mMIC determinations were then used to estimate the concentration of the drugs in serum of mice treated with antifungal drugs by multiplying the antifungal titer of the serum samples by the serum (m)MIC. The serum drug concentrations were also determined by HPLC. The serum concentrations estimated microbiologically showed good agreement with those determined by HPLC, except for itraconazole. Analysis of the serum samples from itraconazole-treated mice by a sensitive bioautography revealed the presence of additional spots, not seen in control samples of itraconazole. The bioautography assay demonstrated that the additional material detected in serum from mice treated with itraconazole was an active metabolite of itraconazole. The data showed that the apparent reduction in the itraconazole serum concentration as determined by HPLC was the result of the formation of an active metabolite, and that the use of a microbiological method to measure serum concentrations of drugs can provide a method for prediction of in vivo efficacy of antifungal drugs.

  2. Identification of metabolites from an active fraction of Cajanus cajan seeds by high resolution mass spectrometry.

    PubMed

    Tekale, Satishkumar S; Jaiwal, Bhimrao V; Padul, Manohar V

    2016-11-15

    Antioxidants are important food additives which prolong food storage due to their protective effects against oxidative degradation of foods by free radicals. However, the synthetic antioxidants show toxic properties. Alternative economical and eco-friendly approach is screening of plant extract for natural antioxidants. Plant phenolics are potent antioxidants. Hence, in present study Cajanus cajan seeds were analyzed for antioxidant activity, Iron chelating activity and total phenolic content. The antioxidant activity using DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging assay showed 71.3% inhibition and 65.8% Iron chelating activity. Total 37 compounds including some short peptides and five major abundant compounds were identified in active fraction of C. cajan seeds. This study concludes that C. cajan seeds are good source of antioxidants and Iron chelating activity. Metabolites found in C. cajan seeds which remove reactive oxygen species (ROS), may help to alleviate oxidative stress associated dreaded health problem like cancer and cardiovascular diseases. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Effects of 3,4-methylenedioxymethamphetamine (MDMA) and its main metabolites on cardiovascular function in conscious rats.

    PubMed

    Schindler, Charles W; Thorndike, Eric B; Blough, Bruce E; Tella, Srihari R; Goldberg, Steven R; Baumann, Michael H

    2014-01-01

    The cardiovascular effects produced by 3,4-methylenedioxymethamphetamine (MDMA; 'Ecstasy') contribute to its acute toxicity, but the potential role of its metabolites in these cardiovascular effects is not known. Here we examined the effects of MDMA metabolites on cardiovascular function in rats. Radiotelemetry was employed to evaluate the effects of s.c. administration of racemic MDMA and its phase I metabolites on BP, heart rate (HR) and locomotor activity in conscious male rats. MDMA (1-20 mg·kg(-1)) produced dose-related increases in BP, HR and activity. The peak effects on HR occurred at a lower dose than peak effects on BP or activity. The N-demethylated metabolite, 3,4-methylenedioxyamphetamine (MDA), produced effects that mimicked those of MDMA. The metabolite 3,4-dihydroxymethamphetamine (HHMA; 1-10 mg·kg(-1)) increased HR more potently and to a greater extent than MDMA, whereas 3,4-dihydroxyamphetamine (HHA) increased HR, but to a lesser extent than HHMA. Neither dihydroxy metabolite altered motor activity. The metabolites 4-hydroxy-3-methoxymethamphetamine (HMMA) and 4-hydroxy-3-methoxyamphetamine (HMA) did not affect any of the parameters measured. The tachycardia produced by MDMA and HHMA was blocked by the β-adrenoceptor antagonist propranolol. Our results demonstrate that HHMA may contribute significantly to the cardiovascular effects of MDMA in vivo. As such, determining the molecular mechanism of action of HHMA and the other hydroxyl metabolites of MDMA warrants further study. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

  4. Effects of 3,4-methylenedioxymethamphetamine (MDMA) and its main metabolites on cardiovascular function in conscious rats

    PubMed Central

    Schindler, Charles W; Thorndike, Eric B; Blough, Bruce E; Tella, Srihari R; Goldberg, Steven R; Baumann, Michael H

    2014-01-01

    BACKGROUND AND PURPOSE The cardiovascular effects produced by 3,4-methylenedioxymethamphetamine (MDMA; ‘Ecstasy’) contribute to its acute toxicity, but the potential role of its metabolites in these cardiovascular effects is not known. Here we examined the effects of MDMA metabolites on cardiovascular function in rats. EXPERIMENTAL APPROACH Radiotelemetry was employed to evaluate the effects of s.c. administration of racemic MDMA and its phase I metabolites on BP, heart rate (HR) and locomotor activity in conscious male rats. KEY RESULTS MDMA (1–20 mg·kg−1) produced dose-related increases in BP, HR and activity. The peak effects on HR occurred at a lower dose than peak effects on BP or activity. The N-demethylated metabolite, 3,4-methylenedioxyamphetamine (MDA), produced effects that mimicked those of MDMA. The metabolite 3,4-dihydroxymethamphetamine (HHMA; 1–10 mg·kg−1) increased HR more potently and to a greater extent than MDMA, whereas 3,4-dihydroxyamphetamine (HHA) increased HR, but to a lesser extent than HHMA. Neither dihydroxy metabolite altered motor activity. The metabolites 4-hydroxy-3-methoxymethamphetamine (HMMA) and 4-hydroxy-3-methoxyamphetamine (HMA) did not affect any of the parameters measured. The tachycardia produced by MDMA and HHMA was blocked by the β-adrenoceptor antagonist propranolol. CONCLUSIONS AND IMPLICATIONS Our results demonstrate that HHMA may contribute significantly to the cardiovascular effects of MDMA in vivo. As such, determining the molecular mechanism of action of HHMA and the other hydroxyl metabolites of MDMA warrants further study. PMID:24328722

  5. Benzene: a case study in parent chemical and metabolite interactions.

    PubMed

    Medinsky, M A; Kenyon, E M; Schlosser, P M

    1995-12-28

    Benzene, an important industrial solvent, is also present in unleaded gasoline and cigarette smoke. The hematotoxic effects of benzene in humans are well documented and include aplastic anemia and pancytopenia, and acute myelogenous leukemia. A combination of metabolites (hydroquinone and phenol for example) is apparently necessary to duplicate the hematotoxic effect of benzene, perhaps due in part to the synergistic effect of phenol on myeloperoxidase-mediated oxidation of hydroquinone to the reactive metabolite benzoquinone. Since benzene and its hydroxylated metabolites (phenol, hydroquinone and catechol) are substrates for the same cytochrome P450 enzymes, competitive interactions among the metabolites are possible. In vivo data on metabolite formation by mice exposed to various benzene concentrations are consistent with competitive inhibition of phenol oxidation by benzene. In vitro studies of the metabolic oxidation of benzene, phenol and hydroquinone are consistent with the mechanism of competitive interaction among the metabolites. The dosimetry of benzene and its metabolites in the target tissue, bone marrow, depends on the balance of activation processes such as enzymatic oxidation and deactivation processes such as conjugation and excretion. Phenol, the primary benzene metabolite, can undergo both oxidation and conjugation. Thus, the potential exists for competition among various enzymes for phenol. However, zonal localization of Phase I and Phase II enzymes in various regions of the liver acinus regulates this competition. Biologically-based dosimetry models that incorporate the important determinants of benzene flux, including interactions with other chemicals, will enable prediction of target tissue doses of benzene and metabolites at low exposure concentrations relevant for humans.

  6. Pharmacokinetic study of tianeptine and its active metabolite MC5 in rats following different routes of administration using a novel liquid chromatography tandem mass spectrometry analytical method.

    PubMed

    Szafarz, Małgorzata; Wencel, Agnieszka; Pociecha, Krzysztof; Fedak, Filip A; Wlaź, Piotr; Wyska, Elżbieta

    2018-02-01

    Tianeptine is an atypical antidepressant with a unique mechanism of action and recently it has been also reported that its major metabolite, compound MC5, possesses pharmacological activity similar to that of the parent drug. The current study aims to investigate the pharmacokinetics (PK) of both tianeptine and MC5 after intravenous or intraperitoneal administration of the parent drug as well as the metabolic ratio of MC5 in rats. To achieve these goals an LC-MS/MS method using the small sample volume for the quantitation of tianeptine and its active metabolite MC5 in rat plasma and liver perfusate has been developed and validated. Following an intravenous administration of tianeptine pharmacokinetic parameters were calculated by non-compartmental analysis. The average tianeptine volume of distribution at steady state was 2.03 L/kg and the systemic clearance equaled 1.84 L/h/kg. The mean elimination half-lives of tianeptine and MC5 metabolite were 1.16 and 7.53 h, respectively. The hepatic clearance of tianeptine determined in the isolated rat liver perfusion studies was similar to the perfusate flow rate despite the low metabolic ratio of MC5. Mass spectrometric analysis of rat bile indicated that tianeptine and MC5 metabolite are eliminated with bile as glucuronide and glutamine conjugates. Bioavailability of tianeptine after its intraperitoneal administration was 69%. The PK model with a metabolite compartment developed in this study for both tianeptine and MC5 metabolite after two routes of administration may facilitate tianeptine dosage selection for the prospective pharmacological experiments.

  7. Analysis of Particulate and Dissolved Metabolite Pools at Station ALOHA

    NASA Astrophysics Data System (ADS)

    Boysen, A.; Carlson, L.; Hmelo, L.; Ingalls, A. E.

    2016-02-01

    Metabolomic studies focus on identifying and quantifying the small organic molecules that are the currency by which an organism lives and dies. Metabolite profiles of microorganisms have the potential to elucidate mechanisms of chemically mediated interactions that influence the success of microbial groups living in a complex environment. However, the chemical diversity of metabolites makes resolving a wide range of compounds analytically challenging. As such, metabolomics has lagged behind other genomic analyses. Here we conduct targeted analysis of over 200 primary and secondary metabolites present in the intracellular and extracellular metabolite pools at Station ALOHA using both reverse phase and hydrophilic interaction liquid chromatography coupled with tandem mass spectrometry. We selected the metabolites in our method due to their known importance in primary metabolism, secondary metabolism, and interactions between marine microorganisms such as nutrient exchange, growth promotion, and cell signaling. Through these analyses we obtain a snapshot of microbial community status that, blended with other forms of genomic data, can further our understanding of microbial dynamics. We hypothesize that monitoring a large suite of important metabolites across environmental gradients and diurnal cycles can elucidate factors controlling the distribution and activity of important microbial groups.

  8. Screening of the in vitro antileishmanial activities of compounds and secondary metabolites isolated from Maytenus guianensis Klotzsch ex Reissek (Celastraceae) chichuá Amazon.

    PubMed

    Meneguetti, Dionatas Ulises de Oliveira; Lima, Renato Abreu; Hurtado, Fernanda Bay; Passarini, Guilherme Matos; Macedo, Sharon Rose Aragão; Barros, Neuza Biguinati de; Oliveira, Flávio Augusto de Souza; Medeiros, Patrícia Soares de Maria de; Militão, Júlio Sancho Linhares Teixeira; Nicolete, Roberto; Facundo, Valdir Alves

    2016-01-01

    Maytenus guianensis is a member of the Celastraceae family that is used in traditional medicine, particularly for its anti-parasitic and anti-cancer effects. To explore the ethnopharmacological potential of this plant, the present study was designed to screen the in vitro antileishmanial activities of extracts and compounds isolated from M. guianensis. Maytenus guianensis stems and leaves were extracted in acetone, followed by the preparation of eluates and isolation of secondary metabolites using chromatography on a glass column with silica gel as the fixed phase. The chemical components were identified using spectroscopic methods, including one- and two-dimensional nuclear magnetic resonance of hydrogen-1 and carbon-13, mass spectroscopy, and infrared spectroscopy. The anti-Leishmania amazonensis activities of these eluates and compounds were evaluated by direct promastigote counting and viability assays. It was found that the hexane bark eluate produced the strongest anti-L. amazonensis effect, with 90-100% inhibition of the promastigote form. The isolated metabolite that produced the best result was tingenone B, followed by a compound formed by the union of tingenone and tingenone B (80-90% inhibition). Maytenus guianensis shows anti-parasite activity that warrants further investigation to determine the mechanisms underlying this antileishmanial effect and to evaluate the pharmacological potential of these eluates and isolated secondary metabolites, while minimizing any adverse effects.

  9. New Methodology for Known Metabolite Identification in Metabonomics/Metabolomics: Topological Metabolite Identification Carbon Efficiency (tMICE).

    PubMed

    Sanchon-Lopez, Beatriz; Everett, Jeremy R

    2016-09-02

    A new, simple-to-implement and quantitative approach to assessing the confidence in NMR-based identification of known metabolites is introduced. The approach is based on a topological analysis of metabolite identification information available from NMR spectroscopy studies and is a development of the metabolite identification carbon efficiency (MICE) method. New topological metabolite identification indices are introduced, analyzed, and proposed for general use, including topological metabolite identification carbon efficiency (tMICE). Because known metabolite identification is one of the key bottlenecks in either NMR-spectroscopy- or mass spectrometry-based metabonomics/metabolomics studies, and given the fact that there is no current consensus on how to assess metabolite identification confidence, it is hoped that these new approaches and the topological indices will find utility.

  10. Metabolite fingerprinting of pennycress (Thlaspi arvense L.) embryos to assess active pathways during oil synthesis

    PubMed Central

    Tsogtbaatar, Enkhtuul; Cocuron, Jean-Christophe; Sonera, Marcos Corchado; Alonso, Ana Paula

    2015-01-01

    Pennycress (Thlaspi arvense L.), a plant naturalized to North America, accumulates high levels of erucic acid in its seeds, which makes it a promising biodiesel and industrial crop. The main carbon sinks in pennycress embryos were found to be proteins, fatty acids, and cell wall, which respectively represented 38.5, 33.2, and 27.0% of the biomass at 21 days after pollination. Erucic acid reached a maximum of 36% of the total fatty acids. Together these results indicate that total oil and erucic acid contents could be increased to boost the economic competitiveness of this crop. Understanding the biochemical basis of oil synthesis in pennycress embryos is therefore timely and relevant to guide future breeding and/or metabolic engineering efforts. For this purpose, a combination of metabolomics approaches was conducted to assess the active biochemical pathways during oil synthesis. First, gas chromatography–mass spectrometry (GC-MS) profiling of intracellular metabolites highlighted three main families of compounds: organic acids, amino acids, and sugars/sugar alcohols. Secondly, these intermediates were quantified in developing pennycress embryos by liquid chromatography–tandem mass spectrometry (LC-MS/MS) in multiple reaction monitoring mode. Finally, partitional clustering analysis grouped the intracellular metabolites that shared a similar pattern of accumulation over time into eight clusters. This study underlined that: (i) sucrose might be stored rather than cleaved into hexoses; (ii) glucose and glutamine would be the main sources of carbon and nitrogen, respectively; and (iii) glycolysis, the oxidative pentose phosphate pathway, the tricarboxylic acid cycle, and the Calvin cycle were active in developing pennycress embryos. PMID:25711705

  11. Novel Sulfur Metabolites of Garlic Attenuate Cardiac Hypertrophy and Remodeling through Induction of Na+/K+-ATPase Expression

    PubMed Central

    Khatua, Tarak N.; Borkar, Roshan M.; Mohammed, Soheb A.; Dinda, Amit K.; Srinivas, R.; Banerjee, Sanjay K.

    2017-01-01

    Epidemiologic studies show an inverse correlation between garlic consumption and progression of cardiovascular disease. However, the molecular basis for the beneficial effect of garlic on the heart is not known. Therefore, the objective of the present study was to (1) investigate the effect of raw garlic on isoproterenol (Iso) induced cardiac hypertrophy (2) find the active metabolites of garlic responsible for the beneficial effect. Cardiac hypertrophy was induced in rats by subcutaneous single injection of Iso 5 mg kg-1 day-1 for 15 days and the effect of garlic (250 mg/kg/day orally) was evaluated. Garlic metabolites in in vivo were identified by LC/MS study. The effect of garlic and its metabolites were evaluated against hypertrophy in H9C2 cells. Garlic normalized cardiac oxidative stress after Iso administration. Cardiac pathology and mitochondrial enzyme activities were improved in hypertrophy heart after garlic administration. Decreased Na+/K+-ATPase protein level that observed in hypertrophy heart was increased after garlic administration. We identified three garlic metabolites in rat serum. To confirm the role of garlic metabolites on cardiac hypertrophy, Na+/K+-ATPase expression and intracellular calcium levels were measured after treating H9C2 cells with raw garlic and two of its active metabolites, allyl methyl sulfide and allyl methyl sulfoxide. Raw garlic and both metabolites increased Na+/K+-ATPase protein level and decreased intracellular calcium levels and cell size in Iso treated H9C2 cells. This antihypertrophic effect of garlic and its sulfur metabolites were lost in H9C2 cells in presence of Na+/K+-ATPase inhibitor. In conclusion, garlic and its active metabolites increased Na+/K+-ATPase in rat heart, and attenuated cardiac hypertrophy and associated remodeling. Our data suggest that identified new garlic metabolites may be useful for therapeutic intervention against cardiac hypertrophy. PMID:28194108

  12. Activity levels of tamoxifen metabolites at the estrogen receptor and the impact of genetic polymorphisms of phase I and II enzymes on their concentration levels in plasma.

    PubMed

    Mürdter, T E; Schroth, W; Bacchus-Gerybadze, L; Winter, S; Heinkele, G; Simon, W; Fasching, P A; Fehm, T; Eichelbaum, M; Schwab, M; Brauch, H

    2011-05-01

    The therapeutic effect of tamoxifen depends on active metabolites, e.g., cytochrome P450 2D6 (CYP2D6) mediated formation of endoxifen. To test for additional relationships, 236 breast cancer patients were genotyped for CYP2D6, CYP2C9, CYP2B6, CYP2C19, CYP3A5, UGT1A4, UGT2B7, and UGT2B15; also, plasma concentrations of tamoxifen and 22 of its metabolites, including the (E)-, (Z)-, 3-, and 4'-hydroxymetabolites as well as their glucuronides, were quantified using liquid chromatography-tandem mass spectrometry (MS). The activity levels of the metabolites were measured using an estrogen response element reporter assay; the strongest estrogen receptor inhibition was found for (Z)-endoxifen and (Z)-4-hydroxytamoxifen (inhibitory concentration 50 (IC50) 3 and 7 nmol/l, respectively). CYP2D6 genotypes explained 39 and 9% of the variability of steady-state concentrations of (Z)-endoxifen and (Z)-4-hydroxytamoxifen, respectively. Among the poor metabolizers, 93% had (Z)-endoxifen levels below IC90 values, underscoring the role of CYP2D6 deficiency in compromised tamoxifen bioactivation. For other enzymes tested, carriers of reduced-function CYP2C9 (*2, *3) alleles had lower plasma concentrations of active metabolites (P < 0.004), pointing to the role of additional pathways.

  13. Influence of light quality on growth, secondary metabolites production and antioxidant activity in callus culture of Rhodiola imbricata Edgew.

    PubMed

    Kapoor, Sahil; Raghuvanshi, Rinky; Bhardwaj, Pushpender; Sood, Hemant; Saxena, Shweta; Chaurasia, Om Prakash

    2018-06-01

    Rhodiola imbricata is a rare medicinal herb well-known for its adaptogenic and antioxidant properties due to the presence of a diverse array of secondary metabolites, including phenylethanoids and phenylpropanoids. These secondary metabolites are generating considerable interest due to their potential applications in pharmaceutical and nutraceutical industries. The present study investigated the influence of light quality on growth, production of industrially important secondary metabolites and antioxidant activity in callus cultures of Rhodiola imbricata. Callus cultures of Rhodiola imbricata were established under different light conditions: 100% red, 100% blue, 100% green, RGB (40% red: 40% green: 20% blue) and 100% white (control). The results showed that the callus cultures grown under red light accumulated maximum amount of biomass (7.43 g/l) on day 21 of culture, as compared to other light conditions. Maximum specific growth rate (0.126 days -1 ) and doubling time (132.66 h) was observed in callus cultures grown under red light. Reverse phase-high performance liquid chromatographic (RP-HPLC) analysis revealed that the callus cultures exposed to blue light accumulated maximum amount of Salidroside (3.12 mg/g DW) on day 21 of culture, as compared to other light conditions. UV-Vis spectrophotometric analysis showed that the callus cultures exposed to blue light accumulated maximum amount of total phenolics (11.84 mg CHA/g DW) and total flavonoids (5.53 mg RE/g DW), as compared to other light conditions. Additionally, callus cultures grown under blue light displayed enhanced DPPH free radical scavenging activity (53.50%). Callus cultures grown under different light conditions showed no significant difference in ascorbic acid content (11.05-13.90 mg/g DW) and total antioxidant capacity (27.37-30.17 mg QE/g DW). The correlation analysis showed a positive correlation between total phenolic content and DPPH free radical scavenging activity in callus

  14. Production of cyathane type secondary metabolites by submerged cultures of Hericium erinaceus and evaluation of their antibacterial activity by direct bioautography.

    PubMed

    Shen, T; Morlock, G; Zorn, H

    2015-01-01

    Fungi of the phylum Basidiomycota are well-known to form a broad spectrum of biologically active secondary metabolites, especially low molecular weight compounds such as terpenoids. Hericium erinaceus produces various cyathane type diterpenoids including erinacines. However, no quantitative data and production kinetics have been reported on the biosynthesis of the erinacines C and P in submerged cultures. In the present study, the production of erinacine C was optimized, and the product formation kinetics as well as the antimicrobial activity were studied by high-performance liquid chromatography (HPLC), high-performance thin-layer chromatography (HPTLC) and direct bioautography. Oatmeal and Edamin ® K were identified to be crucial media components for an efficient production of erinacine C. The highest concentrations of erinacine C were obtained in the optimized culture medium on the 9 th culture day (approximately 260 mg L -1 ). The production of erinacine P was strongly time dependent. The maximum concentration of erinacine P of 184 mg L -1 was observed on the third culture day. Afterwards, the concentrations of erinacine P decreased while the concentrations of erinacine C steadily increased. Comparable results were obtained by HPTLC with UV detection and HPLC with diode-array detection (DAD) analyses. Direct bioautography allowed for an additional analysis of the antimicrobial activity of the secondary metabolites. The C and N sources oatmeal and Edamin ® K induced the formation of erinacine C. Detailed product formation kinetics of the erinacines C and P have been reported for the first time. HPTLC combined with the Aliivibrio fischeri bioassay allowed for an instant detection of cyathane diterpenoids in crude extracts and for an evaluation of the antimicrobial activity of the secondary metabolites directly on the plate.

  15. Bioactive Metabolites from Pathogenic and Endophytic Fungi of Forest Trees.

    PubMed

    Masi, Marco; Maddau, Lucia; Linaldeddu, Benedetto Teodoro; Scanu, Bruno; Evidente, Antonio; Cimmino, Alessio

    2018-01-01

    Fungi play an important role in terrestrial ecosystems interacting positively or negatively with plants. These interactions are complex and the outcomes are different depending on the fungal lifestyles, saprotrophic, mutualistic or pathogenic. Furthermore, fungi are well known for producing secondary metabolites, originating from different biosynthetic pathways, which possess biological properties of considerable biotechnological interest. Among the terrestrial ecosystems, temperate forests represent an enormous reservoir of fungal diversity. This review will highlight the goldmine of secondary metabolites produced by pathogenic and endophytic fungi of forest trees with focus on their biological activities. A structured search of bibliographic databases for peer-reviewed research literature was undertaken using a research discovery application providing access to a large and authoritative source of references. The papers selected were examined and the main results were reported and discussed. Two hundred forthy-one papers were included in the review, outlined a large number of secondary metabolites produced by pathogenic and endophiltic fungi and their biological activities, including phytotoxic, antifungal, antioomycetes, antibacterial, brine shrimp lethality, mosquito biting deterrence and larvicidal, cytotoxic, antiproliferative and many other bioactivities. The findings of this review confirm the importance of secondary metabolites produced by pathogenic and endophytic fungi from forest plants growing in temperate regions as an excellent prospects to discover compounds with new bioactivities and mode of actions. In addition, the potential of some metabolites as a source of new drugs and biopesticides is underlined. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  16. Using High-Throughput Sequencing to Leverage Surveillance of Genetic Diversity and Oseltamivir Resistance: A Pilot Study during the 2009 Influenza A(H1N1) Pandemic

    PubMed Central

    Téllez-Sosa, Juan; Rodríguez, Mario Henry; Gómez-Barreto, Rosa E.; Valdovinos-Torres, Humberto; Hidalgo, Ana Cecilia; Cruz-Hervert, Pablo; Luna, René Santos; Carrillo-Valenzo, Erik; Ramos, Celso; García-García, Lourdes; Martínez-Barnetche, Jesús

    2013-01-01

    Background Influenza viruses display a high mutation rate and complex evolutionary patterns. Next-generation sequencing (NGS) has been widely used for qualitative and semi-quantitative assessment of genetic diversity in complex biological samples. The “deep sequencing” approach, enabled by the enormous throughput of current NGS platforms, allows the identification of rare genetic viral variants in targeted genetic regions, but is usually limited to a small number of samples. Methodology and Principal Findings We designed a proof-of-principle study to test whether redistributing sequencing throughput from a high depth-small sample number towards a low depth-large sample number approach is feasible and contributes to influenza epidemiological surveillance. Using 454-Roche sequencing, we sequenced at a rather low depth, a 307 bp amplicon of the neuraminidase gene of the Influenza A(H1N1) pandemic (A(H1N1)pdm) virus from cDNA amplicons pooled in 48 barcoded libraries obtained from nasal swab samples of infected patients (n  =  299) taken from May to November, 2009 pandemic period in Mexico. This approach revealed that during the transition from the first (May-July) to second wave (September-November) of the pandemic, the initial genetic variants were replaced by the N248D mutation in the NA gene, and enabled the establishment of temporal and geographic associations with genetic diversity and the identification of mutations associated with oseltamivir resistance. Conclusions NGS sequencing of a short amplicon from the NA gene at low sequencing depth allowed genetic screening of a large number of samples, providing insights to viral genetic diversity dynamics and the identification of genetic variants associated with oseltamivir resistance. Further research is needed to explain the observed replacement of the genetic variants seen during the second wave. As sequencing throughput rises and library multiplexing and automation improves, we foresee that the approach

  17. Regulatory cross talk and microbial induction of fungal secondary metabolite gene clusters.

    PubMed

    Nützmann, Hans-Wilhelm; Schroeckh, Volker; Brakhage, Axel A

    2012-01-01

    Filamentous fungi are well-known producers of a wealth of secondary metabolites with various biological activities. Many of these compounds such as penicillin, cyclosporine, or lovastatin are of great importance for human health. Genome sequences of filamentous fungi revealed that the encoded potential to produce secondary metabolites is much higher than the actual number of compounds produced during cultivation in the laboratory. This finding encouraged research groups to develop new methods to exploit the silent reservoir of secondary metabolites. In this chapter, we present three successful strategies to induce the expression of secondary metabolite gene clusters. They are based on the manipulation of the molecular processes controlling the biosynthesis of secondary metabolites and the simulation of stimulating environmental conditions leading to altered metabolic profiles. The presented methods were successfully applied to identify novel metabolites. They can be also used to significantly increase product yields. Copyright © 2012 Elsevier Inc. All rights reserved.

  18. Engineering Microbial Metabolite Dynamics and Heterogeneity.

    PubMed

    Schmitz, Alexander C; Hartline, Christopher J; Zhang, Fuzhong

    2017-10-01

    As yields for biological chemical production in microorganisms approach their theoretical maximum, metabolic engineering requires new tools, and approaches for improvements beyond what traditional strategies can achieve. Engineering metabolite dynamics and metabolite heterogeneity is necessary to achieve further improvements in product titers, productivities, and yields. Metabolite dynamics, the ensemble change in metabolite concentration over time, arise from the need for microbes to adapt their metabolism in response to the extracellular environment and are important for controlling growth and productivity in industrial fermentations. Metabolite heterogeneity, the cell-to-cell variation in a metabolite concentration in an isoclonal population, has a significant impact on ensemble productivity. Recent advances in single cell analysis enable a more complete understanding of the processes driving metabolite heterogeneity and reveal metabolic engineering targets. The authors present an overview of the mechanistic origins of metabolite dynamics and heterogeneity, why they are important, their potential effects in chemical production processes, and tools and strategies for engineering metabolite dynamics and heterogeneity. The authors emphasize that the ability to control metabolite dynamics and heterogeneity will bring new avenues of engineering to increase productivity of microbial strains. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Activation of the sigma-1 receptor by haloperidol metabolites facilitates brain-derived neurotrophic factor secretion from human astroglia.

    PubMed

    Dalwadi, Dhwanil A; Kim, Seongcheol; Schetz, John A

    2017-05-01

    Glial cells play a critical role in neuronal support which includes the production and release of the neurotrophin brain-derived neurotrophic factor (BDNF). Activation of the sigma-1 receptor (S1R) has been shown to attenuate inflammatory stress-mediated brain injuries, and there is emerging evidence that this may involve a BDNF-dependent mechanism. In this report we studied S1R-mediated BDNF release from human astrocytic glial cells. Astrocytes express the S1R, which mediates BDNF release when stimulated with the prototypical S1R agonists 4-PPBP and (+)-SKF10047. This effect could be antagonized by a selective concentration of the S1R antagonist BD1063. Haloperidol is known to have high affinity interactions with the S1R, yet it was unable to facilitate BDNF release. Remarkably, however, two metabolites of haloperidol, haloperidol I and haloperidol II (reduced haloperidol), were discovered to facilitate BDNF secretion and this effect was antagonized by BD1063. Neither 4-PPBP, nor either of the haloperidol metabolites affected the level of BDNF mRNA as assessed by qPCR. These results demonstrate for the first time that haloperidol metabolites I and II facilitate the secretion of BDNF from astrocytes by acting as functionally selective S1R agonists. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Cytotoxicity of lapachol metabolites produced by probiotics.

    PubMed

    Oliveira Silva, E; Cruz de Carvalho, T; Parshikov, I A; Alves dos Santos, R; Silva Emery, F; Jacometti Cardoso Furtado, N A

    2014-07-01

    Probiotics are currently added to a variety of functional foods to provide health benefits to the host and are commonly used by patients with gastrointestinal complaints or diseases. The therapeutic effects of lapachol continue to inspire studies to obtain derivatives with improved bioactivity and lower unwanted effects. Therefore, the general goal of this study was to show that probiotics are able to convert lapachol and are important to assess the effects of bacterial metabolism on drug performance and toxicity. The microbial transformations of lapachol were carried out by Bifidobacterium sp. and Lactobacillus acidophilus and different metabolites were produced in mixed and isolated cultures. The cytotoxic activities against breast cancer and normal fibroblast cell lines of the isolated metabolites (4α-hydroxy-2,2-dimethyl-5-oxo-2,3,4,4α,5,9β-hexahydroindeno[1,2-β]pyran-9β-carboxilic acid, a new metabolite produced by mixed culture and dehydro-α-lapachone produced by isolated cultures) were assessed and compared with those of lapachol. The new metabolite displayed a lower activity against a breast cancer cell line (IC50 = 532.7 μmol l(-1) ) than lapachol (IC50 = 72.3 μmol l(-1) ), while dehydro-α-lapachone (IC50 = 10.4 μmol l(-1) ) displayed a higher activity than lapachol. The present study is the first to demonstrate that probiotics are capable of converting lapachol into the most effective cytotoxic compound against a breast cancer cell line. Probiotics have been used in dairy products to promote human health and have the ability to metabolize drugs and other xenobiotics. Naphthoquinones, such as lapachol, are considered privileged scaffolds due to their high propensity to interact with biological targets. The present study is the first to demonstrate that probiotics are capable of converting lapachol into the most effective cytotoxic compound against a breast cancer cell line. The developed approach highlights the importance of probiotics to assess

  1. Anti-Adhesive Activity of Cranberry Phenolic Compounds and Their Microbial-Derived Metabolites against Uropathogenic Escherichia coli in Bladder Epithelial Cell Cultures.

    PubMed

    de Llano, Dolores González; Esteban-Fernández, Adelaida; Sánchez-Patán, Fernando; Martínlvarez, Pedro J; Moreno-Arribas, Maria Victoria; Bartolomé, Begoña

    2015-05-27

    Cranberry consumption has shown prophylactic effects against urinary tract infections (UTI), although the mechanisms involved are not completely understood. In this paper, cranberry phenolic compounds and their potential microbial-derived metabolites (such as simple phenols and benzoic, phenylacetic and phenylpropionic acids) were tested for their capacity to inhibit the adherence of uropathogenic Escherichia coli (UPEC) ATCC®53503™ to T24 epithelial bladder cells. Catechol, benzoic acid, vanillic acid, phenylacetic acid and 3,4-dihydroxyphenylacetic acid showed anti-adhesive activity against UPEC in a concentration-dependent manner from 100-500 µM, whereas procyanidin A2, widely reported as an inhibitor of UPEC adherence on uroepithelium, was only statistically significant (p < 0.05) at 500 µM (51.3% inhibition). The results proved for the first time the anti-adhesive activity of some cranberry-derived phenolic metabolites against UPEC in vitro, suggesting that their presence in the urine could reduce bacterial colonization and progression of UTI.

  2. Annual ovarian activity monitored by the noninvasive measurement of fecal concentrations of progesterone and 17β-estradiol metabolites in rusa deer (Rusa timorensis)

    PubMed Central

    SUDSUKH, Apichaya; TAYA, Kazuyoshi; WATANABE, Gen; WAJJWALKU, Worawidh; THONGPHAKDEE, Ampika; THONGTIP, Nikorn

    2016-01-01

    To clarify the reproductive cycle of female Rusa deer (Rusa timorensis), the fecal concentrations of progesterone and 17β-estradiol metabolites were measured. Fecal samples were collected on a weekly basis for one year (between October, 2012 and September, 2013) from five healthy adult hinds in Thailand. At the beginning of the study, three hinds were pregnant. Two hinds delivered one healthy offspring, and one hind delivered a stillborn calf. The mating period of Rusa hinds in Thailand is from November to April. In pregnant hinds, fecal progesterone metabolite concentration was high in late pregnancy and abruptly declined to the baseline around parturition, suggesting that the placenta secretes a large amount of progesterone. Fecal 17β-estradiol metabolite concentration remained elevated around the day of parturition. Both concentrations of fecal progesterone and 17β-estradiol metabolites in non-lactating hinds were significantly higher than those in lactating hinds, indicating that ovarian activity of lactating hinds is suppressed by the suckling stimulus of fawn during lactation. The present study demonstrated that monitoring of fecal steroid hormones is useful method for assessing ovarian function in this species. PMID:27570098

  3. Design of new inhibitors for H5N1 avian influenza using a molecular dynamics simulation

    NASA Astrophysics Data System (ADS)

    Park, Jin Woo; Jo, Won Ho

    2008-03-01

    Recently, there has been a growing interest in the treatment of H5N1 avian influenza. One of the most widely used antiviral agents is oseltamivir. However, it has been reported that oseltamivir is not as effective against the neuraminidase subtype N1 as it is against subtypes N2 and N9. In our research we addressed this problem by designing new inhibitors and these altered inhibitor's binding affinities were calculated. In this study, we introduced chemical groups to the existing oseltamivir, so to fit into the newly discovered cavity in the subtype N1. When the binding strengths of the oseltamivir and the newly designed inhibitors for N1 were calculated to examine the drug efficiency through a molecular dynamics simulation, then compared with each other, it was found that one of the designed molecules exhibited a strong binding affinity, with more than twice the binding strength than that of oseltamivir. Since the aforementioned designed inhibitor appears to have the possibility for oral activity according to the criteria of human oral bioavailability, we propose that the inhibitor is a promising antiviral drug for H5N1 avian influenza.

  4. Effects of chloro-s-triazine herbicides and metabolites on aromatase activity in various human cell lines and on vitellogenin production in male carp hepatocytes.

    PubMed Central

    Sanderson, J T; Letcher, R J; Heneweer, M; Giesy, J P; van den Berg, M

    2001-01-01

    We investigated a potential mechanism for the estrogenic properties of three chloro-s-triazine herbicides and six metabolites in vitro in several cell systems. We determined effects on human aromatase (CYP19), the enzyme that converts androgens to estrogens, in H295R (adrenocortical carcinoma), JEG-3 (placental choriocarcinoma), and MCF-7 (breast cancer) cells; we determined effects on estrogen receptor-mediated induction of vitellogenin in primary hepatocyte cultures of adult male carp (Cyprinus carpio). In addition to atrazine, simazine, and propazine, two metabolites--atrazine-desethyl and atrazine-desisopropyl--induced aromatase activity in H295R cells concentration-dependently (0.3-30 microM) and with potencies similar to those of the parent triazines. After a 24-hr exposure to 30 microM of the triazines, an apparent maximum induction of about 2- to 2.5-fold was achieved. The induction responses were confirmed by similar increases in CYP19 mRNA levels, determined by reverse-transcriptase polymerase chain reaction. In JEG-3 cells, where basal aromatase expression is about 15-fold greater than in H295R cells, the induction responses were similar but less pronounced; aromatase expression in MCF-7 cells was neither detectable nor inducible under our culture conditions. The fully dealkylated metabolite atrazine-desethyl-desisopropyl and the three hydroxylated metabolites (2-OH-atrazine-desethyl, -desisopropyl, and -desethyl-desisopropyl) did not induce aromatase activity. None of the triazine herbicides nor their metabolites induced vitellogenin production in male carp hepatocytes; nor did they antagonize the induction of vitellogenin by 100 nM (EC(50) 17beta-estradiol. These findings together with other reports indicate that the estrogenic effects associated with the triazine herbicides in vivo are not estrogen receptor-mediated, but may be explained partly by their ability to induce aromatase in vitro. PMID:11675267

  5. Online effects of transcranial direct current stimulation on prefrontal metabolites in gambling disorder.

    PubMed

    Dickler, Maya; Lenglos, Christophe; Renauld, Emmanuelle; Ferland, Francine; Edden, Richard A; Leblond, Jean; Fecteau, Shirley

    2018-03-15

    Gambling disorder is characterized by persistent maladaptive gambling behaviors and is now considered among substance-related and addictive disorders. There is still unmet therapeutic need for these clinical populations, however recent advances indicate that interventions targeting the Glutamatergic/GABAergic system hold promise in reducing symptoms in substance-related and addictive disorders, including gambling disorder. There is some data indicating that transcranial direct current stimulation may hold clinical benefits in substance use disorders and modulate levels of brain metabolites including glutamate and GABA. The goal of the present work was to test whether this non-invasive neurostimulation method modulates key metabolites in gambling disorder. We conducted a sham-controlled, crossover, randomized study, blinded at two levels in order to characterize the effects of transcranial direct current stimulation over the dorsolateral prefrontal cortex on neural metabolites levels in sixteen patients with gambling disorder. Metabolite levels were measured with magnetic resonance spectroscopy from the right dorsolateral prefrontal cortex and the right striatum during active and sham stimulation. Active as compared to sham stimulation elevated prefrontal GABA levels. There were no significant changes between stimulation conditions in prefrontal glutamate + glutamine and N-acetyl Aspartate, or in striatal metabolite levels. Results also indicated positive correlations between metabolite levels during active, but not sham, stimulation and levels of risk taking, impulsivity and craving. Our findings suggest that transcranial direct current stimulation can modulate GABA levels in patients with gambling disorder which may represent an interesting future therapeutic avenue. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. GC-MS based metabolite profiling of rice Koji fermentation by various fungi.

    PubMed

    Kim, Ah Jin; Choi, Jung Nam; Kim, Jiyoung; Park, Sait Byul; Yeo, Soo Hwan; Choi, Ji Ho; Lee, Choong Hwan

    2010-01-01

    In this study, Aspergillus kawachii, Aspergillus oryzae, and Rhizopus sp., were utilized for rice Koji fermentation, and the metabolites were analyzed in a time-dependent manner by gas chromatography-mass spectrometry. On Principal Component Analysis, the metabolite patterns were clearly distinguished based on the fungi species. This approach revealed that the quantities of glucose, galactose, and glycerol gradually increased as a function of fermentation time in all trials rice Koji fermentation. The time-dependent changes of these metabolites showed significant increases in glucose in the A. oryzae-treated rice, and in glycerol and galactose in the A. kawachii-treated rice. In addition, glycolysis-related enzyme activities were correlated with the changes in these metabolites. The results indicate that time-dependent metabolite production has the potential to be a valuable tool in selecting inoculant fungi and the optimal fermentation time for rice koji.

  7. Different effects of clopidogrel and clarithromycin on the enantioselective pharmacokinetics of sibutramine and its active metabolites in healthy subjects.

    PubMed

    Shinde, Dhananjay D; Kim, Ho-Sook; Choi, Jae-Seok; Pan, Wei; Bae, Soo Kyung; Yeo, Chang-Woo; Shon, Ji-Hong; Kim, Dong-Hyun; Shin, Jae Gook

    2013-05-01

    In this study, we assessed the effects of clopidogrel and clarithromycin, known CYP2B6 and CYP3A inhibitors, respectively, on the enantioselective disposition of racemic sibutramine in conjunction with CYP2B6 polymorphisms in humans. Sibutramine showed enantioselective plasma profiles with consistently higher concentrations of R-enantiomers. Clopidogrel and clarithromycin significantly increased the sibutramine plasma concentration, but their effects differed between enantiomers; a 2.2-fold versus 4.1-fold increase in the AUC in S-enantiomer and 1.8-fold versus 2.0-fold for the R-enantiomer, respectively. The AUCs of S- and R-desmethyl metabolites changed significantly during the clopidogrel phase (P < .001 and P < .001, respectively) but not during the clarithromycin phase (P = .099 and P = .090, respectively). Exposure to sibutramine was higher in subjects with the CYP2B6*6/*6 genotype, but no statistical difference was observed among the CYP2B6 genotypes. These results suggest that the enantioselective disposition of sibutramine and its active metabolites are influenced by the altered genetic and environmental factors of CYP2B6 and CYP3A activity in vivo. © The Author(s) 2013.

  8. Reduced Photoinhibition under Low Irradiance Enhanced Kacip Fatimah (Labisia pumila Benth) Secondary Metabolites, Phenyl Alanine Lyase and Antioxidant Activity

    PubMed Central

    Ibrahim, Mohd Hafiz; Jaafar, Hawa Z.E.

    2012-01-01

    A randomized complete block design experiment was designed to characterize the relationship between production of total flavonoids and phenolics, anthocyanin, photosynthesis, maximum efficiency of photosystem II (Fv/Fm), electron transfer rate (Fm/Fo), phenyl alanine lyase activity (PAL) and antioxidant (DPPH) in Labisia pumila var. alata, under four levels of irradiance (225, 500, 625 and 900 μmol/m2/s) for 16 weeks. As irradiance levels increased from 225 to 900 μmol/m2/s, the production of plant secondary metabolites (total flavonoids, phenolics and antocyanin) was found to decrease steadily. Production of total flavonoids and phenolics reached their peaks under 225 followed by 500, 625 and 900 μmol/m2/s irradiances. Significant positive correlation of production of total phenolics, flavonoids and antocyanin content with Fv/Fm, Fm/Fo and photosynthesis indicated up-regulation of carbon-based secondary metabolites (CBSM) under reduced photoinhibition on the under low light levels condition. At the lowest irradiance levels, Labisia pumila extracts also exhibited a significantly higher antioxidant activity (DPPH) than under high irradiance. The improved antioxidative activity under low light levels might be due to high availability of total flavonoids, phenolics and anthocyanin content in the plant extract. It was also found that an increase in the production of CBSM was due to high PAL activity under low light, probably signifying more availability of phenylalanine (Phe) under this condition. PMID:22754297

  9. The role of 17β-estradiol metabolites in chromium-induced oxidative stress.

    PubMed

    Sawicka, Ewa; Długosz, Anna

    2017-01-01

    The increasing incidence of estrogen-dependent breast cancer and the presence in the environment of a large number of factors that interact with estrogen receptors have sparked interest in chemical influences on estrogen-dependent processes. In a previous work, the authors examined the interaction of estradiol with chromium. In the present article the importance of estradiol biotransformation in these interactions is investigated. There is no information in the available literature about the role of metabolites in exposure to chromium. It seems important because estradiol metabolites have various carcinogenic abilities and their formation during biotransformation could be increased or decreased by environmental enzyme inducers or inhibitors. The metabolites could play a detoxifying role or create a toxic synergism in free radical processes induced by chromium VI (CrVI). The aim of this study was to evaluate the influence of 2 17β-estradiol metabolites - 4-hydroxyestradiol (4-OHE2) and 16α-hydroxyestrone (16α-OHE1) - in conditions of oxidative stress caused by CrVI. Human blood, erythrocytes or mitochondria isolated from human placentas after natural deliveries were used in the experiments. The influence of CrVI, 4-OHE2 and 16-OHE1 on thiobarbituric acid reactive substances (TBARS), the hydroxyl radical (•OH), superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione-S-transferase (GST), and the interactions of the metabolites exposed to chromium expressed by these factors were examined. 4-OHE2 reduced the level of TBARS induced by CrVI in mitochondria (p < 0.05) and in erythrocytes (p < 0.05), and increased SOD activity (p < 0.05). 16α-OHE1 increased the activity of GST in erythrocytes exposed to CrVI (p < 0.05). The metabolites do not have toxic interactions with CrVI. On the contrary, they exhibited a protective effect. The mechanism of protection varied: 4-OHE2 decreased TBARS and increased SOD activity, while 16α-OHE1 increased GST

  10. Secondary metabolites in plant innate immunity: conserved function of divergent chemicals.

    PubMed

    Piasecka, Anna; Jedrzejczak-Rey, Nicolas; Bednarek, Paweł

    2015-05-01

    Plant secondary metabolites carry out numerous functions in interactions between plants and a broad range of other organisms. Experimental evidence strongly supports the indispensable contribution of many constitutive and pathogen-inducible phytochemicals to plant innate immunity. Extensive studies on model plant species, particularly Arabidopsis thaliana, have brought significant advances in our understanding of the molecular mechanisms underpinning pathogen-triggered biosynthesis and activation of defensive secondary metabolites. However, despite the proven significance of secondary metabolites in plant response to pathogenic microorganisms, little is known about the precise mechanisms underlying their contribution to plant immunity. This insufficiency concerns information on the dynamics of cellular and subcellular localization of defensive phytochemicals during the encounters with microbial pathogens and precise knowledge on their mode of action. As many secondary metabolites are characterized by their in vitro antimicrobial activity, these compounds were commonly considered to function in plant defense as in planta antibiotics. Strikingly, recent experimental evidence suggests that at least some of these compounds alternatively may be involved in controlling several immune responses that are evolutionarily conserved in the plant kingdom, including callose deposition and programmed cell death. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  11. A Novel Video Tracking Method to Evaluate the Effect of Influenza Infection and Antiviral Treatment on Ferret Activity

    PubMed Central

    Oh, Ding Yuan; Barr, Ian G.; Hurt, Aeron C.

    2015-01-01

    Ferrets are the preferred animal model to assess influenza virus infection, virulence and transmission as they display similar clinical symptoms and pathogenesis to those of humans. Measures of disease severity in the ferret include weight loss, temperature rise, sneezing, viral shedding and reduced activity. To date, the only available method for activity measurement has been the assignment of an arbitrary score by a ‘blind’ observer based on pre-defined responsiveness scale. This manual scoring method is subjective and can be prone to bias. In this study, we described a novel video-tracking methodology for determining activity changes in a ferret model of influenza infection. This method eliminates the various limitations of manual scoring, which include the need for a sole ‘blind’ observer and the requirement to recognise the ‘normal’ activity of ferrets in order to assign relative activity scores. In ferrets infected with an A(H1N1)pdm09 virus, video-tracking was more sensitive than manual scoring in detecting ferret activity changes. Using this video-tracking method, oseltamivir treatment was found to ameliorate the effect of influenza infection on activity in ferret. Oseltamivir treatment of animals was associated with an improvement in clinical symptoms, including reduced inflammatory responses in the upper respiratory tract, lower body weight loss and a smaller rise in body temperature, despite there being no significant reduction in viral shedding. In summary, this novel video-tracking is an easy-to-use, objective and sensitive methodology for measuring ferret activity. PMID:25738900

  12. Bariatric surgery modulates circulating and cardiac metabolites.

    PubMed

    Ashrafian, Hutan; Li, Jia V; Spagou, Konstantina; Harling, Leanne; Masson, Perrine; Darzi, Ara; Nicholson, Jeremy K; Holmes, Elaine; Athanasiou, Thanos

    2014-02-07

    Bariatric procedures such as the Roux-en-Y gastric bypass (RYGB) operation offer profound metabolic enhancement in addition to their well-recognized weight loss effects. They are associated with significant reduction in cardiovascular disease risk and mortality, which suggests a surgical modification on cardiac metabolism. Metabolic phenotyping of the cardiac tissue and plasma postsurgery may give insight into cardioprotective mechanisms. The aim of the study was to compare the metabolic profiles of plasma and heart tissue extracts from RYGB- and sham-operated Wistar rats to identify the systemic and cardiac signature of metabolic surgery. A total of 27 male Wistar rats were housed individually for a week and subsequently underwent RYGB (n = 13) or sham (n = 14) operation. At week 8 postoperation, a total of 27 plasma samples and 16 heart tissue samples (8 RYGB; 8 Sham) were collected from animals and analyzed using (1)H nuclear magnetic resonance (NMR) spectroscopy and ultra performance liquid chromatography (UPLC-MS) to characterize the global metabolite perturbation induced by RYGB operation. Plasma bile acids, phosphocholines, amino acids, energy-related metabolites, nucleosides and amine metabolites, and cardiac glycogen and amino acids were found to be altered in the RYGB operated group. Correlation networks were used to identify metabolite association. The metabolic phenotype of this bariatric surgical model inferred systematic change in both myocardial and systemic activity post surgery. The altered metabolic profile following bariatric surgery reflects an enhancement of cardiac energy metabolism through TCA cycle intermediates, cardiorenal protective activity, and biochemical caloric restriction. These surgically induced metabolic shifts identify some of the potential mechanisms that contribute toward bariatric cardioprotection through gut microbiota ecological fluxes and an enterocardiac axis to shield against metabolic syndrome of cardiac dysfunction.

  13. The pH-dependent local anesthetic activity of diethylaminoethanol, a procaine metabolite.

    PubMed

    Butterworth, J F; Lief, P A; Strichartz, G R

    1988-04-01

    To test whether the products of procaine hydrolysis have local anesthetic actions resembling those of procaine, the authors compared the ability of procaine and its metabolites diethylaminoethanol (DEAE) and para-aminobenzoic acid (PABA) to block compound action potentials in excised, desheathed frog and rat sciatic nerves. Studies were performed in solutions of impermeant buffers at pH 7.4 (corresponding to mammalian physiologic pH) and at pH 9.2 (close to the pKa of procaine and DEAE) to test for extracellular pH-dependent increases in drug permeation and potency. Both procaine and DEAE inhibited compound action potentials at pH 7.4 and 9.2 in a reversible and dose-dependent manner, and both were approximately ten-fold more potent at pH 9.2 than at pH 7.4, procaine inhibiting the action potential height by 50% at 0.15 mM (pH 9.2) and 1.1 mM (pH 7.4), DEAE at 4 mM (pH 9.2) and 70 mM (pH 7.4). In contrast, PABA at concentrations up to 25 mM and at either pH failed to inhibit compound action potentials, and did not modify the effects of DEAE when both drugs were given together. Procaine produced greater use-dependent block at the higher pH and at higher stimulation rates (100 Hz vs. 40 Hz); DEAE produced almost no use-dependent block. These observations suggest: 1) that DEAE might account for some of the neuropharmacologic activity of procaine in techniques that favor the accumulation of metabolites (such as those requiring large doses or prolonged infusions); and 2) that alkalinization of procaine and DEAE solutions appears to increase their potency for both resting and use-dependent block of action potentials.

  14. Metabolite fingerprinting of pennycress ( Thlaspi arvense L.) embryos to assess active pathways during oil synthesis

    DOE PAGES

    Tsogtbaatar, Enkhtuul; Cocuron, Jean -Christophe; Sonera, Marcos Corchado; ...

    2015-02-22

    Pennycress ( Thlaspi arvense L.), a plant naturalized to North America, accumulates high levels of erucic acid in its seeds, which makes it a promising biodiesel and industrial crop. The main carbon sinks in pennycress embryos were found to be proteins, fatty acids, and cell wall, which respectively represented 38.5, 33.2, and 27.0% of the biomass at 21 days after pollination. Erucic acid reached a maximum of 36% of the total fatty acids. Together these results indicate that total oil and erucic acid contents could be increased to boost the economic competitiveness of this crop. Understanding the biochemical basis ofmore » oil synthesis in pennycress embryos is therefore timely and relevant to guide future breeding and/or metabolic engineering efforts. For this purpose, a combination of metabolomics approaches was conducted to assess the active biochemical pathways during oil synthesis. First, gas chromatography-mass spectrometry (GC-MS) profiling of intracellular metabolites highlighted three main families of compounds: organic acids, amino acids, and sugars/sugar alcohols. Secondly, these intermediates were quantified in developing pennycress embryos by liquid chromatography-tandem mass spectrometry (LC-MS/MS) in multiple reaction monitoring mode. Finally, partitional clustering analysis grouped the intracellular metabolites that shared a similar pattern of accumulation over time into eight clusters. In conclusion, this study underlined that: (i) sucrose might be stored rather than cleaved into hexoses; (ii) glucose and glutamine would be the main sources of carbon and nitrogen, respectively; and (iii) glycolysis, the oxidative pentose phosphate pathway, the tricarboxylic acid cycle, and the Calvin cycle were active in developing pennycress embryos.« less

  15. Thermogenic effects of sibutramine and its metabolites

    PubMed Central

    Connoley, Ian P; Liu, Yong-Ling; Frost, Ian; Reckless, Ian P; Heal, David J; Stock, Michael J

    1999-01-01

    The thermogenic activity of the serotonin and noradrenaline reuptake inhibitor sibutramine (BTS 54524; Reductil) was investigated by measuring oxygen consumption (VO2) in rats treated with sibutramine or its two pharmacologically-active metabolites. Sibutramine caused a dose-dependent rise in VO2, with a dose of 10 mg kg−1 of sibutramine or its metabolites producing increases of up to 30% that were sustained for at least 6 h, and accompanied by significant increases (0.5–1.0°C) in body temperature. Based on the accumulation in vivo of radiolabelled 2-deoxy-[3H]-glucose, sibutramine had little or no effect on glucose utilization in most tissues, but caused an 18 fold increase in brown adipose tissue (BAT). Combined high, non-selective doses (20 mg kg−1) of the β-adrenoceptor antagonists, atenolol and ICI 118551, inhibited completely the VO2 response to sibutramine, but the response was unaffected by low, β1-adrenoceptor-selective (atenolol) or β2-adrenoceptor-selective (ICI 118551) doses (1 mg kg−1). The ganglionic blocking agent, chlorisondamine (15 mg kg−1), inhibited completely the VO2 response to the metabolites of sibutramine, but had no effect on the thermogenic response to the β3-adrenoceptor-selective agonist BRL 35135. Similar thermogenic responses were produced by simultaneous injection of nisoxetine and fluoxetine at doses (30 mg kg−1) that had no effect on VO2 when injected individually. It is concluded that stimulation of thermogenesis by sibutramine requires central reuptake inhibition of both serotonin and noradrenaline, resulting in increased efferent sympathetic activation of BAT thermogenesis via β3-adrenoceptor, and that this contributes to the compound's activity as an anti-obesity agent. PMID:10217544

  16. Selective Synthesis and Biological Evaluation of Sulfate-Conjugated Resveratrol Metabolites

    PubMed Central

    Hoshino, Juma; Park, Eun-Jung; Kondratyuk, Tamara P.; Marler, Laura; Pezzuto, John M.; van Breemen, Richard B.; Mo, Shunyan; Li, Yongchao; Cushman, Mark

    2010-01-01

    Five resveratrol sulfate metabolites were synthesized and assessed for activities known to be mediated by resveratrol: inhibition of tumor necrosis factor (TNF)-α-induced NFκB activity, cylcooxygenases (COX-1 and COX-2), aromatase, nitric oxide production in endotoxin-stimulated macrophages, and proliferation of KB or MCF7 cells, induction of quinone reductase 1 (QR1), accumulation in the sub-G1 phase of the cell cycle, and quenching of 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical. Two metabolites showed activity in these assays; the 3-sulfate exhibited QR1 induction, DPPH free radical scavenging, and COX-1 and COX-2 inhibitory activities, and the 4′-sulfate inhibited NFκB induction, as well as COX-1 and COX-2 activities. Resveratrol, as well as its 3′-sulfate and 4-sulfate, inhibit NO production by NO scavenging and down-regulation of iNOS expression in RAW 264.7 cells. Resveratrol sulfates displayed low antiproliferative activity and negligible uptake in MCF7 cells. PMID:20527891

  17. Identification of Sildenafil (Viagra) and Its Metabolite (UK 103,320) in Six Aviation Fatalities

    DTIC Science & Technology

    2006-02-01

    Identification of Sildenafil ( Viagra ®) and Its Metabolite (UK-103,320) in Six Aviation Fatalities Robert D. Johnson Russell J. Lewis Civil...DOT/FAA/AM-06/3 4. Title and Subtitle 5. Report Date February 2006 Identification of Sildenafil ( Viagra ®) and Its Metabolite (UK-103,320...report presents a rapid and reliable method for the identification and quantitation of sildenafil ( Viagra ®) and its active metabolite, UK-103,320. This

  18. A cellular system for quantitation of vitamin K cycle activity: structure-activity effects on vitamin K antagonism by warfarin metabolites

    PubMed Central

    Haque, Jamil A.; McDonald, Matthew G.; Kulman, John D.

    2014-01-01

    Warfarin and other 4-hydroxycoumarins inhibit vitamin K epoxide reductase (VKOR) by depleting reduced vitamin K that is required for posttranslational modification of vitamin K–dependent clotting factors. In vitro prediction of the in vivo potency of vitamin K antagonists is complicated by the complex multicomponent nature of the vitamin K cycle. Here we describe a sensitive assay that enables quantitative analysis of γ-glutamyl carboxylation and its antagonism in live cells. We engineered a human embryonic kidney (HEK) 293–derived cell line (HEK 293-C3) to express a chimeric protein (F9CH) comprising the Gla domain of factor IX fused to the transmembrane and cytoplasmic regions of proline-rich Gla protein 2. Maximal γ-glutamyl carboxylation of F9CH required vitamin K supplementation, and was dose-dependently inhibited by racemic warfarin at a physiologically relevant concentration. Cellular γ-glutamyl carboxylation also exhibited differential VKOR inhibition by warfarin enantiomers (S > R) consistent with their in vivo potencies. We further analyzed the structure-activity relationship for inhibition of γ-glutamyl carboxylation by warfarin metabolites, observing tolerance to phenolic substitution at the C-5 and especially C-6, but not C-7 or C-8, positions on the 4-hydroxycoumarin nucleus. After correction for in vivo concentration and protein binding, 10-hydroxywarfarin and warfarin alcohols were predicted to be the most potent inhibitory metabolites in vivo. PMID:24297869

  19. Deep Sea Actinomycetes and Their Secondary Metabolites

    PubMed Central

    Kamjam, Manita; Sivalingam, Periyasamy; Deng, Zinxin; Hong, Kui

    2017-01-01

    Deep sea is a unique and extreme environment. It is a hot spot for hunting marine actinomycetes resources and secondary metabolites. The novel deep sea actinomycete species reported from 2006 to 2016 including 21 species under 13 genera with the maximum number from Microbacterium, followed by Dermacoccus, Streptomyces and Verrucosispora, and one novel species for the other 9 genera. Eight genera of actinomycetes were reported to produce secondary metabolites, among which Streptomyces is the richest producer. Most of the compounds produced by the deep sea actinomycetes presented antimicrobial and anti-cancer cell activities. Gene clusters related to biosynthesis of desotamide, heronamide, and lobophorin have been identified from the deep sea derived Streptomyces. PMID:28507537

  20. Early phenylpropanoid biosynthetic steps in Cannabis sativa: link between genes and metabolites.

    PubMed

    Docimo, Teresa; Consonni, Roberto; Coraggio, Immacolata; Mattana, Monica

    2013-06-28

    Phenylalanine ammonia-lyase (PAL), Cinnamic acid 4-hydroxylase (C4H) and 4-Coumarate: CoA ligase (4CL) catalyze the first three steps of the general phenylpropanoid pathway whereas chalcone synthase (CHS) catalyzes the first specific step towards flavonoids production. This class of specialized metabolites has a wide range of biological functions in plant development and defence and a broad spectrum of therapeutic activities for human health. In this study, we report the isolation of hemp PAL and 4CL cDNA and genomic clones. Through in silico analysis of their deduced amino acid sequences, more than an 80% identity with homologues genes of other plants was shown and phylogenetic relationships were highlighted. Quantitative expression analysis of the four above mentioned genes, PAL and 4CL enzymatic activities, lignin content and NMR metabolite fingerprinting in different Cannabis sativa tissues were evaluated. Furthermore, the use of different substrates to assay PAL and 4CL enzymatic activities indicated that different isoforms were active in different tissues. The diversity in secondary metabolites content observed in leaves (mainly flavonoids) and roots (mainly lignin) was discussed in relation to gene expression and enzymatic activities data.

  1. Early Phenylpropanoid Biosynthetic Steps in Cannabis sativa: Link between Genes and Metabolites

    PubMed Central

    Docimo, Teresa; Consonni, Roberto; Coraggio, Immacolata; Mattana, Monica

    2013-01-01

    Phenylalanine ammonia-lyase (PAL), Cinnamic acid 4-hydroxylase (C4H) and 4-Coumarate: CoA ligase (4CL) catalyze the first three steps of the general phenylpropanoid pathway whereas chalcone synthase (CHS) catalyzes the first specific step towards flavonoids production. This class of specialized metabolites has a wide range of biological functions in plant development and defence and a broad spectrum of therapeutic activities for human health. In this study, we report the isolation of hemp PAL and 4CL cDNA and genomic clones. Through in silico analysis of their deduced amino acid sequences, more than an 80% identity with homologues genes of other plants was shown and phylogenetic relationships were highlighted. Quantitative expression analysis of the four above mentioned genes, PAL and 4CL enzymatic activities, lignin content and NMR metabolite fingerprinting in different Cannabis sativa tissues were evaluated. Furthermore, the use of different substrates to assay PAL and 4CL enzymatic activities indicated that different isoforms were active in different tissues. The diversity in secondary metabolites content observed in leaves (mainly flavonoids) and roots (mainly lignin) was discussed in relation to gene expression and enzymatic activities data. PMID:23812081

  2. Metabolomics for secondary metabolite research.

    PubMed

    Breitling, Rainer; Ceniceros, Ana; Jankevics, Andris; Takano, Eriko

    2013-11-11

    Metabolomics, the global characterization of metabolite profiles, is becoming an increasingly powerful tool for research on secondary metabolite discovery and production. In this review we discuss examples of recent technological advances and biological applications of metabolomics in the search for chemical novelty and the engineered production of bioactive secondary metabolites.

  3. Comparing metabolite profiles of habitual diet in serum and urine123

    PubMed Central

    Playdon, Mary C; Sampson, Joshua N; Cross, Amanda J; Sinha, Rashmi; Guertin, Kristin A; Moy, Kristin A; Rothman, Nathaniel; Irwin, Melinda L; Mayne, Susan T; Stolzenberg-Solomon, Rachael; Moore, Steven C

    2016-01-01

    Background: Diet plays an important role in chronic disease etiology, but some diet-disease associations remain inconclusive because of methodologic limitations in dietary assessment. Metabolomics is a novel method for identifying objective dietary biomarkers, although it is unclear what dietary information is captured from metabolites found in serum compared with urine. Objective: We compared metabolite profiles of habitual diet measured from serum with those measured from urine. Design: We first estimated correlations between consumption of 56 foods, beverages, and supplements assessed by a food-frequency questionnaire, with 676 serum and 848 urine metabolites identified by untargeted liquid chromatography mass spectrometry, ultra-high performance liquid chromatography tandem mass spectrometry, and gas chromatography mass spectrometry in a colon adenoma case–control study (n = 125 cases and 128 controls) while adjusting for age, sex, smoking, fasting, case-control status, body mass index, physical activity, education, and caloric intake. We controlled for multiple comparisons with the use of a false discovery rate of <0.1. Next, we created serum and urine multiple-metabolite models to predict food intake with the use of 10-fold crossvalidation least absolute shrinkage and selection operator regression for 80% of the data; predicted values were created in the remaining 20%. Finally, we compared predicted values with estimates obtained from self-reported intake for metabolites measured in serum and urine. Results: We identified metabolites associated with 46 of 56 dietary items; 417 urine and 105 serum metabolites were correlated with ≥1 food, beverage, or supplement. More metabolites in urine (n = 154) than in serum (n = 39) were associated uniquely with one food. We found previously unreported metabolite associations with leafy green vegetables, sugar-sweetened beverages, citrus, added sugar, red meat, shellfish, desserts, and wine. Prediction of dietary

  4. Tryptophan Metabolism in Rat Liver After Administration of Tryptophan, Kynurenine Metabolites, and Kynureninase Inhibitors.

    PubMed

    Badawy, Abdulla A-B; Bano, Samina

    2016-01-01

    Rat liver tryptophan (Trp), kynurenine pathway metabolites, and enzymes deduced from product/substrate ratios were assessed following acute and/or chronic administration of kynurenic acid (KA), 3-hydroxykynurenine (3-HK), 3-hydroxyanthranilic acid (3-HAA), Trp, and the kynureni-nase inhibitors benserazide (BSZ) and carbidopa (CBD). KA activated Trp 2,3-dioxygenase (TDO), possibly by increasing liver 3-HAA, but inhibited kynurenine aminotransferase (KAT) and kynureninase activities with 3-HK as substrate. 3-HK inhibited kynureninase activity from 3-HK. 3-HAA stimulated TDO, but inhibited kynureninase activity from K and 3-HK. Trp (50 mg/kg) increased kynurenine metabolite concentrations and KAT from K, and exerted a temporary stimulation of TDO. The kynureninase inhibitors BSZ and CBD also inhibited KAT, but stimulated TDO. BSZ abolished or strongly inhibited the Trp-induced increases in liver Trp and kynurenine metabolites. The potential effects of these changes in conditions of immune activation, schizophrenia, and other disease states are discussed.

  5. Detection of antibacterial-like activity on a silica surface: fluoroquinolones and their environmental metabolites.

    PubMed

    Lewis, Gareth; Juhasz, Albert; Smith, Euan

    2011-08-01

    BACKGROUND, SCOPE, AND AIMS: Antibacterial fluoroquinolones (FQs) are third-generation antibiotics that are commonly used as therapeutic treatments of respiratory and urinary tract infections. They are used far less in intensively farmed animal production systems, though their use may be permitted in the veterinary treatments of flocks or in medicated feeds. When used, only a fraction of ingested parent FQ actually reaches the in vivo target site of infection, while the remainder is excreted as the parent FQ and its metabolized products. In many species' metabolism, enrofloxacin (EF) is converted into ciprofloxacin (CF) while both FQs are classified as parent FQs in human treatments. It is therefore likely that both FQs and their metabolic products will contribute to a common pool of metabolites in biological wastes. Wastes from intensive farming practices are either directly applied to agricultural land without treatment or may be temporarily stored prior to disposal. However, human waste is treated in sewage treatment plants (STPs) where it is converted into biosolids. In the storage or treatment process of STPs, FQs and their in vivo metabolites are further converted into other environmental metabolites (FQEMs) by ex vivo physicochemical processes that act and interact to produce complex mixtures of FQEMs, some of which have antibacterial-like activities. Biosolids are then often applied to agricultural land as a fertilizer amendment where FQs and FQEMs can be further converted into additional FQEMs by soil processes. It is therefore likely that FQ-contaminated biowaste-treated soils will contain complex mixtures of FQEMs, some of which may have antibacterial-like activities that may be expressed on bacteria endemic to the receiving agricultural soil environment. Concern has arisen in the scientific and in the general community that repeated use of FQ-contaminated biowaste as fertilizer amendments of nutrient-impoverished agricultural land may create a selective

  6. Three New and Eleven Known Unusual C25 Steroids: Activated Production of Silent Metabolites in a Marine-Derived Fungus by Chemical Mutagenesis Strategy using Diethyl Sulphate

    PubMed Central

    Xia, Ming-Wen; Cui, Cheng-Bin; Li, Chang-Wei; Wu, Chang-Jing

    2014-01-01

    Three new (1–3) and 11 known (4–14) C25 steroids with an unusual bicyclo[4.4.1]A/B ring system were isolated by tracing newly produced metabolites in the EtOAc extract of an antitumor mutant AD-1-2 obtained by the diethyl sulphate (DES) mutagenesis of a marine-derived Penicillium purpurogenum G59. HPLC-PDAD-UV and HPLC-ESI-MS analyses indicated that the G59 strain did not produce these metabolites and the production of 1–14 in the mutant AD-1-2 extract was caused by the activation of silent metabolites in the original G59 strain by DES mutagenesis. The structures of the new compounds, named antineocyclocitrinols A (1) and B (2) and 23-O-methylantineocyclocitrinol (3), including their absolute configurations were determined by various spectroscopic methods, especially the NMR and Mo2-induced CD analyses. Compounds 1–3 provide the first examples of the C25 bicyclo[4.4.1]A/B ring steroids with the Z-configuration of 20,22-double bond. All of 1–14 weakly inhibited several human cancer cell lines to varying extents. These results provided additional examples for the successful application of the chemical mutagenesis strategy using DES to discover new compounds by activating silent metabolites in fungal isolates and supported also the effectiveness and usefulness of this new strategy. PMID:24633254

  7. Lichen secondary metabolites affect growth of Physcomitrella patens by allelopathy.

    PubMed

    Goga, Michal; Antreich, Sebastian J; Bačkor, Martin; Weckwerth, Wolfram; Lang, Ingeborg

    2017-05-01

    Lichen secondary metabolites can function as allelochemicals and affect the development and growth of neighboring bryophytes, fungi, vascular plants, microorganisms, and even other lichens. Lichen overgrowth on bryophytes is frequently observed in nature even though mosses grow faster than lichens, but there is still little information on the interactions between lichens and bryophytes.In the present study, we used extracts from six lichen thalli containing secondary metabolites like usnic acid, protocetraric acid, atranorin, lecanoric acid, nortistic acid, and thamnolic acid. To observe the influence of these metabolites on bryophytes, the moss Physcomitrella patens was cultivated for 5 weeks under laboratory conditions and treated with lichen extracts. Toxicity of natural mixtures of secondary metabolites was tested at three selected doses (0.001, 0.01, and 0.1 %). When the mixture contained substantial amounts of usnic acid, we observed growth inhibition of protonemata and reduced development of gametophores. Significant differences in cell lengths and widths were also noticed. Furthermore, usnic acid had a strong effect on cell division in protonemata suggesting a strong impact on the early stages of bryophyte development by allelochemicals contained in the lichen secondary metabolites.Biological activities of lichen secondary metabolites were confirmed in several studies such as antiviral, antibacterial, antitumor, antiherbivore, antioxidant, antipyretic, and analgetic action or photoprotection. This work aimed to expand the knowledge on allelopathic effects on bryophyte growth.

  8. Secondary metabolites from marine microorganisms.

    PubMed

    Kelecom, Alphonse

    2002-03-01

    After 40 years of intensive research, chemistry of marine natural products has become a mature field. Since 1995, there are signals of decreased interest in the search of new metabolites from traditional sources such as macroalgae and octocorals, and the number of annual reports on marine sponges stabilized. On the contrary, metabolites from microorganisms is a rapidly growing field, due, at least in part, to the suspicion that a number of metabolites obtained from algae and invertebrates may be produced by associated microorganisms. Studies are concerned with bacteria and fungi, isolated from seawater, sediments, algae, fish and mainly from marine invertebrates such as sponges, mollusks, tunicates, coelenterates and crustaceans. Although it is still to early to define tendencies, it may be stated that the metabolites from microorganisms are in most cases quite different from those produced by the invertebrate hosts. Nitrogenated metabolites predominate over acetate derivatives, and terpenes are uncommon. Among the latter, sesquiterpenes, diterpenes and carotenes have been isolated; among nitrogenated metabolites, amides, cyclic peptides and indole alkaloids predominate.

  9. Phytochemical characterization and biological activity of secondary metabolites from three Limonium species

    USDA-ARS?s Scientific Manuscript database

    Plant tissues typically contain a diverse complement of secondary metabolites that provide protection against various biotic and abiotic hazards. Chemical similarities are commonly used to interpret phylogenetic relationships among plant taxa. The comparative phytochemical constituents of three Limo...

  10. Identification of drug metabolites in human plasma or serum integrating metabolite prediction, LC-HRMS and untargeted data processing.

    PubMed

    Jacobs, Peter L; Ridder, Lars; Ruijken, Marco; Rosing, Hilde; Jager, Nynke Gl; Beijnen, Jos H; Bas, Richard R; van Dongen, William D

    2013-09-01

    Comprehensive identification of human drug metabolites in first-in-man studies is crucial to avoid delays in later stages of drug development. We developed an efficient workflow for systematic identification of human metabolites in plasma or serum that combines metabolite prediction, high-resolution accurate mass LC-MS and MS vendor independent data processing. Retrospective evaluation of predictions for 14 (14)C-ADME studies published in the period 2007-January 2012 indicates that on average 90% of the major metabolites in human plasma can be identified by searching for accurate masses of predicted metabolites. Furthermore, the workflow can identify unexpected metabolites in the same processing run, by differential analysis of samples of drug-dosed subjects and (placebo-dosed, pre-dose or otherwise blank) control samples. To demonstrate the utility of the workflow we applied it to identify tamoxifen metabolites in serum of a breast cancer patient treated with tamoxifen. Previously published metabolites were confirmed in this study and additional metabolites were identified, two of which are discussed to illustrate the advantages of the workflow.

  11. Response of Cultured Maize Cells to (+)-Abscisic Acid, (-)-Abscisic Acid, and Their Metabolites.

    PubMed Central

    Balsevich, J. J.; Cutler, A. J.; Lamb, N.; Friesen, L. J.; Kurz, E. U.; Perras, M. R.; Abrams, S. R.

    1994-01-01

    The metabolism and effects of (+)-S- and (-)-R-abscisic acid (ABA) and some metabolites were studied in maize (Zea mays L. cv Black Mexican Sweet) suspension-cultured cells. Time-course studies of metabolite formation were performed in both cells and medium via analytical high-performance liquid chromatography. Metabolites were isolated and identified using physical and chemical methods. At 10 [mu]M concentration and 28[deg] C, (+)-ABA was metabolized within 24 h, yielding natural (-)-phaseic acid [(-)-PA] as the major product. The unnatural enantiomer (-)-ABA was less than 50% metabolized within 24 h and gave primarily (-)-7[prime]-hydroxyABA [(-)-7[prime]-HOABA], together with (+)-PA and ABA glucose ester. The distribution of metabolites in cells and medium was different, reflecting different sites of metabolism and membrane permeabilities of conjugated and nonconjugated metabolites. The results imply that (+)-ABA was oxidized to (-)-PA inside the cell, whereas (-)-ABA was converted to (-)-7[prime]-HOABA at the cell surface. Growth of maize cells was inhibited by both (+)- and (-)-ABA, with only weak contributions from their metabolites. The concentration of (+)-ABA that caused a 50% inhibition of growth of maize cells was approximately 1 [mu]M, whereas that for its metabolite (-)-PA was approximately 50 [mu]M. (-)-ABA was less active than (+)-ABA, with 50% growth inhibition observed at about 10 [mu]M. (-)-7[prime]-HOABA was only weakly active, with 50% inhibition caused by approximately 500 [mu]M. Time-course studies of medium pH indicated that (+)-ABA caused a transient pH increase (+0.3 units) at 6 h after addition that was not observed in controls or in samples treated with (-)-PA. The effect of (-)-ABA on medium Ph was marginal. No racemization at C-1[prime] of (+)-ABA, (-)-ABA, or metabolites was observed during the studies. PMID:12232311

  12. Enhanced photo(geno)toxicity of demethylated chlorpromazine metabolites

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

    Palumbo, Fabrizio

    Chlorpromazine (CPZ) is an anti-psychotic drug widely used to treat disorders such as schizophrenia or manic-depression. Unfortunately, CPZ exhibits undesirable side effects such as phototoxic and photoallergic reactions in humans. In general, the influence of drug metabolism on this type of reactions has not been previously considered in photosafety testing. Thus, the present work aims to investigate the possible photo(geno)toxic potential of drug metabolites, using CPZ as an established reference compound. In this case, the metabolites selected for the study are demethylchlorpromazine (DMCPZ), didemethylchlorpromazine (DDMCPZ) and chlorpromazine sulfoxide (CPZSO). The demethylated CPZ metabolites DMCPZ and DDMCPZ maintain identical chromophore tomore » the parent drug. In this work, it has been found that the nature of the aminoalkyl side chain modulates the hydrophobicity and the photochemical properties (for instance, the excited state lifetimes), but it does not change the photoreactivity pattern, which is characterized by reductive photodehalogenation, triggered by homolytic carbon-chlorine bond cleavage with formation of highly reactive aryl radical intermediates. Accordingly, these metabolites are phototoxic to cells, as revealed by the 3T3 NRU assay; their photo-irritation factors are even higher than that of CPZ. The same trend is observed in photogenotoxicity studies, both with isolated and with cellular DNA, where DMCPZ and DDMCPZ are more active than CPZ itself. In summary, side-chain demethylation of CPZ, as a consequence of Phase I biotransformation, does not result a photodetoxification. Instead, it leads to metabolites that exhibit in an even enhanced photo(geno)toxicity. - Highlights: • Demethylated CPZ metabolites are phototoxic to cells, as revealed by the NRU assay. • Single cell electrophoresis (Comet Assay) confirms the photodamage to cellular DNA. • DNA single strand breaks formation is observed on agarose gel electrophoresis.

  13. Absorption rates and free radical scavenging values of vitamin C-lipid metabolites in human lymphoblastic cells.

    PubMed

    Weeks, Benjamin S; Perez, Pedro P

    2007-10-01

    In this study we investigated the cellular absorption rates, antioxidant and free radical scavenging activity of vitamin C-lipid metabolites. The absorption was measured in a human lymphoblastic cell line using a spectrophotometric technique. Cellular vitamin C levels in the human lymphoblastic H9 cell line were measured using the 2,4-dinitrophenylhydrazine spectrophotometric technique. Free radical scavenging activity of vitamin C-lipid metabolites was measured by the reduction of 1,1-diphenyl-2-picryl hydrazyl (DPPH) to 1,1-diphenyl-2-picryl hydrazine. Vitamin C-lipid metabolite scavenging of peroxyl radical oxygen reactive species (ORAC) was determined by fluorescence spectrophotometry. Compared to ascorbic acid (AA), calcium ascorbate (CaA), and calcium ascorbate-calcium threonate-dehydroascorbate (Ester-C), vitamin C-lipid metabolites (PureWay-C) were more rapidly absorbed by the H9 human T-lymphocytes. The vitamin C-lipid metabolites (PureWay-C) also reduced pesticide-induced T-lymphocyte aggregation by 84%, while calcium ascorbate-calcium threonate-dehydroascorbate (Ester-C) reduced aggregation by only 34%. The vitamin C-lipid metabolites (PureWay-C) demonstrated free radical scavenging activity of nearly 100% reduction of DPPH at 20 microg/ml and oxygen radical scavenging of over 1200 micro Trolox equivalents per gram. These data demonstrate that the vitamin C-lipid metabolites (PureWay-C) are more rapidly taken-up and absorbed by cells than other forms of vitamin C, including Ester-C. This increased rate of absorption correlates with an increased protection of the T-lymphocytes from pesticide toxicities. Further, vitamin C-lipid metabolites (PureWay-C) are a potent antioxidant and have significant free radical scavenging capabilities.

  14. Antiviral activity of A771726, the active metabolite of leflunomide, against Junín virus.

    PubMed

    Sepúlveda, Claudia S; García, Cybele C; Damonte, Elsa B

    2018-05-01

    The aim of this study was to investigate the effect of A771726, the active metabolite of leflunomide, (CONICET-UBA), Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad against the infection with Junín virus (JUNV), agent of Argentine hemorrhagic fever (AHF). The treatment with non-cytotoxic concentrations of A771726 of Vero and A549 cells infected with JUNV inhibited virus replication in a dose-dependent manner, as determined by virus yield reduction assay. The antiviral effectiveness of A771726 was not importantly affected by the multiplicity of infection and the virus strain. Moreover, the combination of A771726 and ribavirin had a significantly more potent antiviral activity than each single drug treatment. Mechanistic studies showed that the main action of A771726 is exerted before 6 h of JUNV infection. Accordingly, inhibition of viral RNA synthesis was detected in treated infected cells by real time RT-PCR. The exogenous addition of uridine or orotic acid produced a partial reversal of the inhibitory effect of A771726 on infective virus production whereas a total reversion was detected on JUNV RNA synthesis, probably by restoration of the enzymatic activity of dihydroorotate dehydrogenase (DHODH) and the intracellular pyrimidine pools. In conclusion, these results suggest that the antiviral target would be viral RNA synthesis through pyrimidine depletion, but any other effect of the compound on JUNV infection cannot be excluded. This study opens the possibility of the therapeutic application of a wide spectrum host-targeted compound alone or in combination with ribavirin to combat AHF as well as other human pathogenic arenaviruses. © 2018 Wiley Periodicals, Inc.

  15. Development of novel metabolite-responsive transcription factors via transposon-mediated protein fusion.

    PubMed

    Younger, Andrew K D; Su, Peter Y; Shepard, Andrea J; Udani, Shreya V; Cybulski, Thaddeus R; Tyo, Keith E J; Leonard, Joshua N

    2018-02-01

    Naturally evolved metabolite-responsive biosensors enable applications in metabolic engineering, ranging from screening large genetic libraries to dynamically regulating biosynthetic pathways. However, there are many metabolites for which a natural biosensor does not exist. To address this need, we developed a general method for converting metabolite-binding proteins into metabolite-responsive transcription factors-Biosensor Engineering by Random Domain Insertion (BERDI). This approach takes advantage of an in vitro transposon insertion reaction to generate all possible insertions of a DNA-binding domain into a metabolite-binding protein, followed by fluorescence activated cell sorting to isolate functional biosensors. To develop and evaluate the BERDI method, we generated a library of candidate biosensors in which a zinc finger DNA-binding domain was inserted into maltose binding protein, which served as a model well-studied metabolite-binding protein. Library diversity was characterized by several methods, a selection scheme was deployed, and ultimately several distinct and functional maltose-responsive transcriptional biosensors were identified. We hypothesize that the BERDI method comprises a generalizable strategy that may ultimately be applied to convert a wide range of metabolite-binding proteins into novel biosensors for applications in metabolic engineering and synthetic biology. © The Author(s) 2018. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  16. Kinetic, thermodynamic and structural analysis of tamiphosphor binding to neuraminidase of H1N1 (2009) pandemic influenza.

    PubMed

    Albiñana, Carlos Berenguer; Machara, Aleš; Řezáčová, Pavlína; Pachl, Petr; Konvalinka, Jan; Kožíšek, Milan

    2016-10-04

    Influenza virus causes severe respiratory infections that are responsible for up to half a million deaths worldwide each year. Two inhibitors targeting viral neuraminidase have been approved to date (oseltamivir, zanamivir). However, the rapid development of antiviral drug resistance and the efficient transmission of resistant viruses among humans represent serious threats to public health. The approved influenza neuraminidase inhibitors have (oxa)cyclohexene scaffolds designed to mimic the oxonium transition state during enzymatic cleavage of sialic acid. Their active forms contain a carboxylate that interacts with three arginine residues in the enzyme active site. Recently, the phosphonate group was successfully used as an isostere of the carboxylate in oseltamivir, and the resulting compound, tamiphosphor, was identified as a highly active neuraminidase inhibitor. However, the structure of the complex of this promising inhibitor with neuraminidase has not yet been reported. Here, we analyzed the interaction of a set of oseltamivir and tamiphosphor derivatives with neuraminidase from the A/California/07/2009 (H1N1) influenza virus. We thermodynamically characterized the binding of oseltamivir carboxylate or tamiphosphor to the neuraminidase catalytic domain by protein microcalorimetry, and we determined crystal structure of the catalytic domain in complex with tamiphosphor at 1.8 Å resolution. This structural information should aid rational design of the next generation of neuraminidase inhibitors. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  17. Detection and characterization of a new metabolite of 17alpha-methyltestosterone.

    PubMed

    Pozo, Oscar J; Van Eenoo, Peter; Deventer, Koen; Lootens, Leen; Van Thuyne, Wim; Parr, Maria K; Schänzer, Wilhelm; Sancho, Juan V; Hernández, Felix; Meuleman, Philip; Leroux-Roels, Geert; Delbeke, Frans T

    2009-11-01

    The misuse of the anabolic steroid methyltestosterone is currently routinely monitored in doping control laboratories by gas chromatography-mass spectrometry (GC-MS) of two of its metabolites: 17alpha-methyl-5beta-androstane-3alpha,17beta-diol and 17alpha-methyl-5alpha-androstane-3alpha,17beta-diol. Because of the absence of any easy ionizable moiety, these metabolites are poorly detectable using liquid chromatography-tandem mass spectrometry (LC-MS/MS) with electrospray ionization (ESI). In this study, the metabolism of methyltestosterone has been reinvestigated by the use of a precursor ion scan method in LC-ESI-MS/MS. Two metabolites have been detected using this method. Both compounds have been confirmed in postadministration urine samples of an urokinase plasminogen activator-severe combined immunodeficiency (uPA-SCID) mouse with humanized liver and were characterized by LC-MS/MS and GC-MS using both quadrupole and time of flight analyzers. From the detailed study of the fragmentation, these metabolites were proposed to be epimethyltestosterone and a dehydrogenated compound. Epimethyltestosterone has previously been described as a minor metabolite, whereas the occurrence of the oxidized metabolite has not been reported. Comparison with the synthesized reference revealed that the structure of the dehydrogenated metabolite is 6-ene-epimethyltestosterone. A selected reaction monitoring method including three transitions for each metabolite has been developed and applied to samples from an excretion study and to samples declared positive after GC-MS analysis. 6-Ene-epimethyltestosterone was found in all samples, showing its applicability in the detection of methyltestosterone misuse.

  18. Isolation and identification of metabolites of osthole in rats.

    PubMed

    Lv, X; Wang, C-Y; Hou, J; Zhang, B-J; Deng, S; Tian, Y; Huang, S-S; Zhang, H-L; Shu, X-H; Zhen, Y-H; Liu, K-X; Yao, J-H; Ma, X-C

    2012-11-01

    Osthole (Ost), one of the major components of Cnidium monnieri (L.) Cusson, is had the structure of an isopentenoxy-coumarin with a range of pharmacological activities. In the present study, the metabolism of Ost in male Sprague-Dawley rats was investigated by identifying Ost metabolites excreted in rat urine. Following an oral dose of 40 mg/kg Ost, 10 phase I and 3 phase II metabolites were isolated from the urine of rats, and their structures identified on the basis of a range of spectroscopic data, including 2D-NMR techniques. These metabolites were fully characterized as 5'-hydroxyl-osthole (M-1), osthenol (M-2), 4'-hydroxyl-osthole (M-3), 3, 5'-dihydroxyl-osthole (M-4), 5'-hydroxyl-osthenol (M-5), 4'-hydroxyl-2', 3'-dihydro-osthenol (M-6), 4'-hydroxyl-osthenol (M-7), 3, 4'-dihydroxyl-osthole (M-8), 2', 3'-dihydroxyl-osthole (M-9), 5'-hydroxyl-2', 3'-dihydroosthole (M-10), osthenol-7-O-β-D-glucuronide (M-11), osthole-4'-O-β-D-glucuronide (M-12) and osthole-5'-O-β-D-glycuronate (M-13). This is the first identification of M-1, M-3 to M-13 in vivo. On the basis of the metabolites profile, a possible metabolic pathway for Ost metabolism in rats has been proposed. This is the first systematic study on the phases I and II metabolites of 8-isopentenoxy-coumarin derivative.

  19. Bioactive Secondary Metabolites from a Thai Collection of Soil and Marine-Derived Fungi of the Genera Neosartorya and Aspergillus.

    PubMed

    Zin, War War May; Prompanya, Chadaporn; Buttachon, Suradet; Kijjoa, Anake

    2016-01-01

    Fungi are microorganisms which can produce interesting secondary metabolites with structural diversity. Although terrestrial fungi have been extensively investigated for their bioactive secondary metabolites such as antibiotics, marine-derived fungi have only recently attracted attention of Natural Products chemists. Our group has been working on the secondary metabolites produced by the cultures of the fungi of the genera Neosartorya and Aspergillus, collected from soil and marine environments from the tropical region for the purpose of finding new leads for anticancer and antibacterial drugs. This review covers only the secondary metabolites of four soil and six marine-derived species of Neosarorya as well as a new species of marine-derived Aspergillus, investigated by our group. In total, we have isolated fifty three secondary metabolites which can be categorized as polyketides (two), isocoumarins (six), terpenoids (two), meroterpenes (fourteen), alkaloids (twenty eight) and cyclic peptide (one). The anticancer and antibacterial activities of these fungal metabolites are also discussed. Among fifty three secondary metabolites isolated, only the alkaloid eurochevalierine and the cadinene sesquiterpene, isolated from the soil fungus N. pseudofisheri, showed relevant in vitro cytostatic activity against glioblastoma (U373) and non-small cell lung cancer (A549) cell lines while the meroditerpene aszonapyrone A exhibited strong antibacterial activity against multidrug-resistant Gram-positive bacteria and also strong antibiofilm activity in these isolates.

  20. Biological responses of progestogen metabolites in normal and cancerous human breast.

    PubMed

    Pasqualini, Jorge R; Chetrite, Gérard S

    2010-12-01

    At present, more than 200 progestogen molecules are available, but their biological response is a function of various factors: affinity to progesterone or other receptors, their structure, the target tissues considered, biological response, experimental conditions, dose, method of administration and metabolic transformations. Metabolic transformation is of huge importance because in various biological processes the metabolic product(s) not only control the activity of the maternal hormone but also have an important activity of its own. In this regard, it was observed that the 20-dihydro derivative of the progestogen dydrogesterone (Duphaston®) is significantly more active than the parent compound in inhibiting sulfatase and 17β-hydroxysteroid dehydrogenase in human breast cancer cells. Estrone sulfatase activity is also inhibited by norelgestromin, a norgestimate metabolite. Interesting information was obtained with a similar progestogen, tibolone, which is rapidly metabolized into the active 3α/3β-hydroxy and 4-ene metabolites. All these metabolites can inhibit sulfatase and 17β-hydroxysteroid dehydrogenase and stimulate sulfotransferase in human breast cancer cells. Another attractive aspect is the metabolic transformation of progesterone itself in human breast tissues. In the normal breast progesterone is mainly converted to 4-ene derivatives, whereas in the tumor tissue it is converted mostly to 5α-pregnane derivatives. 20α-Dihydroprogesterone is found mainly in normal breast tissue and possesses antiproliferative properties as well as the ability to act as an anti-aromatase agent. Consequently, this progesterone metabolite could be involved in the control of estradiol production in the normal breast and therefore implicated in one of the multifactorial mechanisms of the breast carcinogenesis process. In conclusion, a better understanding of both natural and synthetic hormone metabolic transformations and their control could potentially provide

  1. MSD-MAP: A Network-Based Systems Biology Platform for Predicting Disease-Metabolite Links.

    PubMed

    Wathieu, Henri; Issa, Naiem T; Mohandoss, Manisha; Byers, Stephen W; Dakshanamurthy, Sivanesan

    2017-01-01

    Cancer-associated metabolites result from cell-wide mechanisms of dysregulation. The field of metabolomics has sought to identify these aberrant metabolites as disease biomarkers, clues to understanding disease mechanisms, or even as therapeutic agents. This study was undertaken to reliably predict metabolites associated with colorectal, esophageal, and prostate cancers. Metabolite and disease biological action networks were compared in a computational platform called MSD-MAP (Multi Scale Disease-Metabolite Association Platform). Using differential gene expression analysis with patient-based RNAseq data from The Cancer Genome Atlas, genes up- or down-regulated in cancer compared to normal tissue were identified. Relational databases were used to map biological entities including pathways, functions, and interacting proteins, to those differential disease genes. Similar relational maps were built for metabolites, stemming from known and in silico predicted metabolite-protein associations. The hypergeometric test was used to find statistically significant relationships between disease and metabolite biological signatures at each tier, and metabolites were assessed for multi-scale association with each cancer. Metabolite networks were also directly associated with various other diseases using a disease functional perturbation database. Our platform recapitulated metabolite-disease links that have been empirically verified in the scientific literature, with network-based mapping of jointly-associated biological activity also matching known disease mechanisms. This was true for colorectal, esophageal, and prostate cancers, using metabolite action networks stemming from both predicted and known functional protein associations. By employing systems biology concepts, MSD-MAP reliably predicted known cancermetabolite links, and may serve as a predictive tool to streamline conventional metabolomic profiling methodologies. Copyright© Bentham Science Publishers; For any

  2. Effects of nelfinavir and its M8 metabolite on lymphocyte P-glycoprotein activity during antiretroviral therapy.

    PubMed

    Donahue, John P; Dowdy, David; Ratnam, Krishna K; Hulgan, Todd; Price, James; Unutmaz, Derya; Nicotera, Janet; Raffanti, Steven; Becker, Mark; Haas, David W

    2003-01-01

    The efflux pump P-glycoprotein decreases drug penetration into cells and tissues. To determine whether nelfinavir or its metabolites inhibit P-glycoprotein in lymphocytes from a healthy volunteer, whole blood cells from human immunodeficiency virus-negative donors were incubated either in human plasma to which nelfinavir or its M8 metabolite were added ex vivo or in plasma from human immunodeficiency virus-positive patients receiving nelfinavir. The 50% P-glycoprotein inhibitory concentrations of purified nelfinavir and M8 were 10.9 micromol/L and 29.5 micromol/L, respectively, for CD4(+) T cells and 19.3 micromol/L and >48 micromol/L, respectively, for CD8(+) T cells. Significant inhibitory activity was present in plasma from 27 of 46 patients (59%) receiving nelfinavir. Plasma nelfinavir concentrations correlated with percent inhibition on CD4(+) (rho = 0.85, P <.0001) and CD8(+) (rho = 0.83, P <.0001) T cells. The M8 concentrations correlated weakly with both inhibition and nelfinavir concentrations. On the basis of our findings in lymphocytes from a healthy volunteer exposed to plasma from human immunodeficiency virus-positive patients, we believe it is likely that CD4(+) and CD8(+) lymphocytes in patients receiving nelfinavir as therapy for human immunodeficiency virus may have P-glycoprotein inhibited by plasma concentrations of nelfinavir.

  3. Metabolism and excretion kinetics of {sup 14}C-labeled and non-labeled difloxacin in pigs after oral administration, and antimicrobial activity of manure containing difloxacin and its metabolites

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

    Sukul, Premasis; Lamshoeft, Marc; Kusari, Souvik

    2009-04-15

    Fluoroquinolones are amongst the most important antibiotics used in veterinary medicine. On this account the behavior of difloxacin (DIF) and its metabolites was investigated by administering the {sup 14}C-labeled and non-labeled veterinary drug to fattening pigs. The excretion kinetics were determined after daily collection of manure. Sarafloxacin (SAR) was found to be the major metabolite, three further trace metabolites were also recovered, applying high-resolution (HR) mass spectrometric technique. The identification of DIF and SAR was confirmed by comparison with the spectroscopic and chromatographic data of the authentic references. The identification of the three trace metabolites was performed by HR-MS/MS. Onlymore » 8.1% of the administered radioactivity remained in the pig after 10 days and DIF accounted for 95.9% of the radioactivity excreted. More than 99% of the labeled compounds were detected and identified in the manure. The mean recoveries for all single electrolytes were {>=}94%. Linearity was established over concentration range 10-10,000 {mu}g/kg manure with a correlation coefficient {>=}0.99. By using in vitro antimicrobial activity tests against a group of standard pathogenic control strains, the results showed that the residual antibiotic concentrations in the manure of pigs are high enough to exhibit antibacterial activity.« less

  4. Effects of Secondary Plant Metabolites on Microbial Populations: Changes in Community Structure and Metabolic Activity in Contaminated Environments.

    PubMed

    Musilova, Lucie; Ridl, Jakub; Polivkova, Marketa; Macek, Tomas; Uhlik, Ondrej

    2016-07-29

    Secondary plant metabolites (SPMEs) play an important role in plant survival in the environment and serve to establish ecological relationships between plants and other organisms. Communication between plants and microorganisms via SPMEs contained in root exudates or derived from litter decomposition is an example of this phenomenon. In this review, the general aspects of rhizodeposition together with the significance of terpenes and phenolic compounds are discussed in detail. We focus specifically on the effect of SPMEs on microbial community structure and metabolic activity in environments contaminated by polychlorinated biphenyls (PCBs) and polyaromatic hydrocarbons (PAHs). Furthermore, a section is devoted to a complex effect of plants and/or their metabolites contained in litter on bioremediation of contaminated sites. New insights are introduced from a study evaluating the effects of SPMEs derived during decomposition of grapefruit peel, lemon peel, and pears on bacterial communities and their ability to degrade PCBs in a long-term contaminated soil. The presented review supports the "secondary compound hypothesis" and demonstrates the potential of SPMEs for increasing the effectiveness of bioremediation processes.

  5. Effects of Secondary Plant Metabolites on Microbial Populations: Changes in Community Structure and Metabolic Activity in Contaminated Environments

    PubMed Central

    Musilova, Lucie; Ridl, Jakub; Polivkova, Marketa; Macek, Tomas; Uhlik, Ondrej

    2016-01-01

    Secondary plant metabolites (SPMEs) play an important role in plant survival in the environment and serve to establish ecological relationships between plants and other organisms. Communication between plants and microorganisms via SPMEs contained in root exudates or derived from litter decomposition is an example of this phenomenon. In this review, the general aspects of rhizodeposition together with the significance of terpenes and phenolic compounds are discussed in detail. We focus specifically on the effect of SPMEs on microbial community structure and metabolic activity in environments contaminated by polychlorinated biphenyls (PCBs) and polyaromatic hydrocarbons (PAHs). Furthermore, a section is devoted to a complex effect of plants and/or their metabolites contained in litter on bioremediation of contaminated sites. New insights are introduced from a study evaluating the effects of SPMEs derived during decomposition of grapefruit peel, lemon peel, and pears on bacterial communities and their ability to degrade PCBs in a long-term contaminated soil. The presented review supports the “secondary compound hypothesis” and demonstrates the potential of SPMEs for increasing the effectiveness of bioremediation processes. PMID:27483244

  6. The circadian oscillator in Synechococcus elongatus controls metabolite partitioning during diurnal growth.

    PubMed

    Diamond, Spencer; Jun, Darae; Rubin, Benjamin E; Golden, Susan S

    2015-04-14

    Synechococcus elongatus PCC 7942 is a genetically tractable model cyanobacterium that has been engineered to produce industrially relevant biomolecules and is the best-studied model for a prokaryotic circadian clock. However, the organism is commonly grown in continuous light in the laboratory, and data on metabolic processes under diurnal conditions are lacking. Moreover, the influence of the circadian clock on diurnal metabolism has been investigated only briefly. Here, we demonstrate that the circadian oscillator influences rhythms of metabolism during diurnal growth, even though light-dark cycles can drive metabolic rhythms independently. Moreover, the phenotype associated with loss of the core oscillator protein, KaiC, is distinct from that caused by absence of the circadian output transcriptional regulator, RpaA (regulator of phycobilisome-associated A). Although RpaA activity is important for carbon degradation at night, KaiC is dispensable for those processes. Untargeted metabolomics analysis and glycogen kinetics suggest that functional KaiC is important for metabolite partitioning in the morning. Additionally, output from the oscillator functions to inhibit RpaA activity in the morning, and kaiC-null strains expressing a mutant KaiC phosphomimetic, KaiC-pST, in which the oscillator is locked in the most active output state, phenocopies a ΔrpaA strain. Inhibition of RpaA by the oscillator in the morning suppresses metabolic processes that normally are active at night, and kaiC-null strains show indications of oxidative pentose phosphate pathway activation as well as increased abundance of primary metabolites. Inhibitory clock output may serve to allow secondary metabolite biosynthesis in the morning, and some metabolites resulting from these processes may feed back to reinforce clock timing.

  7. Microbial communication leading to the activation of silent fungal secondary metabolite gene clusters

    PubMed Central

    Netzker, Tina; Fischer, Juliane; Weber, Jakob; Mattern, Derek J.; König, Claudia C.; Valiante, Vito; Schroeckh, Volker; Brakhage, Axel A.

    2015-01-01

    Microorganisms form diverse multispecies communities in various ecosystems. The high abundance of fungal and bacterial species in these consortia results in specific communication between the microorganisms. A key role in this communication is played by secondary metabolites (SMs), which are also called natural products. Recently, it was shown that interspecies “talk” between microorganisms represents a physiological trigger to activate silent gene clusters leading to the formation of novel SMs by the involved species. This review focuses on mixed microbial cultivation, mainly between bacteria and fungi, with a special emphasis on the induced formation of fungal SMs in co-cultures. In addition, the role of chromatin remodeling in the induction is examined, and methodical perspectives for the analysis of natural products are presented. As an example for an intermicrobial interaction elucidated at the molecular level, we discuss the specific interaction between the filamentous fungi Aspergillus nidulans and Aspergillus fumigatus with the soil bacterium Streptomyces rapamycinicus, which provides an excellent model system to enlighten molecular concepts behind regulatory mechanisms and will pave the way to a novel avenue of drug discovery through targeted activation of silent SM gene clusters through co-cultivations of microorganisms. PMID:25941517

  8. Microbial communication leading to the activation of silent fungal secondary metabolite gene clusters.

    PubMed

    Netzker, Tina; Fischer, Juliane; Weber, Jakob; Mattern, Derek J; König, Claudia C; Valiante, Vito; Schroeckh, Volker; Brakhage, Axel A

    2015-01-01

    Microorganisms form diverse multispecies communities in various ecosystems. The high abundance of fungal and bacterial species in these consortia results in specific communication between the microorganisms. A key role in this communication is played by secondary metabolites (SMs), which are also called natural products. Recently, it was shown that interspecies "talk" between microorganisms represents a physiological trigger to activate silent gene clusters leading to the formation of novel SMs by the involved species. This review focuses on mixed microbial cultivation, mainly between bacteria and fungi, with a special emphasis on the induced formation of fungal SMs in co-cultures. In addition, the role of chromatin remodeling in the induction is examined, and methodical perspectives for the analysis of natural products are presented. As an example for an intermicrobial interaction elucidated at the molecular level, we discuss the specific interaction between the filamentous fungi Aspergillus nidulans and Aspergillus fumigatus with the soil bacterium Streptomyces rapamycinicus, which provides an excellent model system to enlighten molecular concepts behind regulatory mechanisms and will pave the way to a novel avenue of drug discovery through targeted activation of silent SM gene clusters through co-cultivations of microorganisms.

  9. Oxidative metabolites of lycopene and their biological functions

    USDA-ARS?s Scientific Manuscript database

    To gain a better understanding of the beneficial biological activities of lycopene on cancer prevention, a greater knowledge of the metabolism of lycopene is needed. In particular, the identification of lycopene metabolites and oxidation products in vivo; the importance of tissue specific lycopene c...

  10. Biochemical Characterization of the Active Anti-Hepatitis C Virus Metabolites of 2,6-Diaminopurine Ribonucleoside Prodrug Compared to Sofosbuvir and BMS-986094

    PubMed Central

    Ehteshami, Maryam; Tao, Sijia; Ozturk, Tugba; Zhou, Longhu; Cho, Jong Hyun; Zhang, Hongwang; Amiralaei, Sheida; Shelton, Jadd R.; Lu, Xiao; Khalil, Ahmed; Domaoal, Robert A.; Stanton, Richard A.; Suesserman, Justin E.; Lin, Biing; Lee, Sam S.; Amblard, Franck; Whitaker, Tony; Coats, Steven J.

    2016-01-01

    Ribonucleoside analog inhibitors (rNAI) target the hepatitis C virus (HCV) RNA-dependent RNA polymerase nonstructural protein 5B (NS5B) and cause RNA chain termination. Here, we expand our studies on β-d-2′-C-methyl-2,6-diaminopurine-ribonucleotide (DAPN) phosphoramidate prodrug 1 (PD1) as a novel investigational inhibitor of HCV. DAPN-PD1 is metabolized intracellularly into two distinct bioactive nucleoside triphosphate (TP) analogs. The first metabolite, 2′-C-methyl-GTP, is a well-characterized inhibitor of NS5B polymerase, whereas the second metabolite, 2′-C-methyl-DAPN-TP, behaves as an adenosine base analog. In vitro assays suggest that both metabolites are inhibitors of NS5B-mediated RNA polymerization. Additional factors, such as rNAI-TP incorporation efficiencies, intracellular rNAI-TP levels, and competition with natural ribonucleotides, were examined in order to further characterize the potential role of each nucleotide metabolite in vivo. Finally, we found that although both 2′-C-methyl-GTP and 2′-C-methyl-DAPN-TP were weak substrates for human mitochondrial RNA (mtRNA) polymerase (POLRMT) in vitro, DAPN-PD1 did not cause off-target inhibition of mtRNA transcription in Huh-7 cells. In contrast, administration of BMS-986094, which also generates 2′-C-methyl-GTP and previously has been associated with toxicity in humans, caused detectable inhibition of mtRNA transcription. Metabolism of BMS-986094 in Huh-7 cells leads to 87-fold higher levels of intracellular 2′-C-methyl-GTP than DAPN-PD1. Collectively, our data characterize DAPN-PD1 as a novel and potent antiviral agent that combines the delivery of two active metabolites. PMID:27216050

  11. Isolation of bacterial metabolites as natural inducers for larval settlement in the marine polychaete Hydroides elegans (Haswell).

    PubMed

    Harder, Tilmann; Lau, Stanley Chun Kwan; Dahms, Hans-Uwe; Qian, Pei-Yuan

    2002-10-01

    The bacterial component of marine biofilms plays an important role in the induction of larval settlement in the polychaete Hydroides elegans. In this study, we provide experimental evidence that bacterial metabolites comprise the chemical signal for larval settlement. Bacteria were isolated from biofilms, purified and cultured according to standard procedures. Bacterial metabolites were isolated from spent culture broth by chloroform extraction as well as by closed-loop stripping and adsorption of volatile components on surface-modified silica gel. A pronounced biological activity was exclusively observed when concentrated metabolites were adsorbed on activated charcoal. Larvae did not respond to waterbome metabolites when prevented from contacting the bacterial film surface. These results indicate that an association of the chemical signal with a sorbent-like substratum may be an essential cofactor for the expression of biological activity. The functional role of bacterial exopolymers as an adsorptive matrix for larval settlement signals is discussed.

  12. Physicochemical characteristics of structurally determined metabolite-protein and drug-protein binding events with respect to binding specificity

    PubMed Central

    Korkuć, Paula; Walther, Dirk

    2015-01-01

    To better understand and ultimately predict both the metabolic activities as well as the signaling functions of metabolites, a detailed understanding of the physical interactions of metabolites with proteins is highly desirable. Focusing in particular on protein binding specificity vs. promiscuity, we performed a comprehensive analysis of the physicochemical properties of compound-protein binding events as reported in the Protein Data Bank (PDB). We compared the molecular and structural characteristics obtained for metabolites to those of the well-studied interactions of drug compounds with proteins. Promiscuously binding metabolites and drugs are characterized by low molecular weight and high structural flexibility. Unlike reported for drug compounds, low rather than high hydrophobicity appears associated, albeit weakly, with promiscuous binding for the metabolite set investigated in this study. Across several physicochemical properties, drug compounds exhibit characteristic binding propensities that are distinguishable from those associated with metabolites. Prediction of target diversity and compound promiscuity using physicochemical properties was possible at modest accuracy levels only, but was consistently better for drugs than for metabolites. Compound properties capturing structural flexibility and hydrogen-bond formation descriptors proved most informative in PLS-based prediction models. With regard to diversity of enzymatic activities of the respective metabolite target enzymes, the metabolites benzylsuccinate, hypoxanthine, trimethylamine N-oxide, oleoylglycerol, and resorcinol showed very narrow process involvement, while glycine, imidazole, tryptophan, succinate, and glutathione were identified to possess broad enzymatic reaction scopes. Promiscuous metabolites were found to mainly serve as general energy currency compounds, but were identified to also be involved in signaling processes and to appear in diverse organismal systems (digestive and nervous

  13. Physicochemical characteristics of structurally determined metabolite-protein and drug-protein binding events with respect to binding specificity.

    PubMed

    Korkuć, Paula; Walther, Dirk

    2015-01-01

    To better understand and ultimately predict both the metabolic activities as well as the signaling functions of metabolites, a detailed understanding of the physical interactions of metabolites with proteins is highly desirable. Focusing in particular on protein binding specificity vs. promiscuity, we performed a comprehensive analysis of the physicochemical properties of compound-protein binding events as reported in the Protein Data Bank (PDB). We compared the molecular and structural characteristics obtained for metabolites to those of the well-studied interactions of drug compounds with proteins. Promiscuously binding metabolites and drugs are characterized by low molecular weight and high structural flexibility. Unlike reported for drug compounds, low rather than high hydrophobicity appears associated, albeit weakly, with promiscuous binding for the metabolite set investigated in this study. Across several physicochemical properties, drug compounds exhibit characteristic binding propensities that are distinguishable from those associated with metabolites. Prediction of target diversity and compound promiscuity using physicochemical properties was possible at modest accuracy levels only, but was consistently better for drugs than for metabolites. Compound properties capturing structural flexibility and hydrogen-bond formation descriptors proved most informative in PLS-based prediction models. With regard to diversity of enzymatic activities of the respective metabolite target enzymes, the metabolites benzylsuccinate, hypoxanthine, trimethylamine N-oxide, oleoylglycerol, and resorcinol showed very narrow process involvement, while glycine, imidazole, tryptophan, succinate, and glutathione were identified to possess broad enzymatic reaction scopes. Promiscuous metabolites were found to mainly serve as general energy currency compounds, but were identified to also be involved in signaling processes and to appear in diverse organismal systems (digestive and nervous

  14. Transfer of metabolites across the peroxisomal membrane.

    PubMed

    Antonenkov, Vasily D; Hiltunen, J Kalervo

    2012-09-01

    Peroxisomes perform a large variety of metabolic functions that require a constant flow of metabolites across the membranes of these organelles. Over the last few years it has become clear that the transport machinery of the peroxisomal membrane is a unique biological entity since it includes nonselective channels conducting small solutes side by side with transporters for 'bulky' solutes such as ATP. Electrophysiological experiments revealed several channel-forming activities in preparations of plant, mammalian, and yeast peroxisomes and in glycosomes of Trypanosoma brucei. The properties of the first discovered peroxisomal membrane channel - mammalian Pxmp2 protein - have also been characterized. The channels are apparently involved in the formation of peroxisomal shuttle systems and in the transmembrane transfer of various water-soluble metabolites including products of peroxisomal β-oxidation. These products are processed by a large set of peroxisomal enzymes including carnitine acyltransferases, enzymes involved in the synthesis of ketone bodies, thioesterases, and others. This review discusses recent data pertaining to solute permeability and metabolite transport systems in peroxisomal membranes and also addresses mechanisms responsible for the transfer of ATP and cofactors such as an ATP transporter and nudix hydrolases. Copyright © 2012 Elsevier B.V. All rights reserved.

  15. Environmentally relevant mixing ratios in cumulative assessments: a study of the kinetics of pyrethroids and their ester cleavage metabolites in blood and brain; and the effect of a pyrethroid mixture on the motor activity of rats.

    PubMed

    Starr, James M; Graham, Stephen E; Ross, David G; Tornero-Velez, Rogelio; Scollon, Edward J; Devito, Michael J; Crofton, Kevin M; Wolansky, Marcelo J; Hughes, Michael F

    2014-06-05

    National surveys of United States households and child care centers have demonstrated that pyrethroids are widely distributed in indoor habited dwellings and this suggests that co-exposure to multiple pyrethroids occurs in nonoccupational settings. The purpose of this research was to use an environmentally relevant mixture of pyrethroids to assess their cumulative effect on motor activity and develop kinetic profiles for these pyrethroids and their hydrolytic metabolites in brain and blood of rats. Rats were dosed orally at one of two levels (1.5× or 5.0× the calculated dose that decreases rat motor activity by 30%) with a mixture of cypermethrin, deltamethrin, esfenvalerate, cis-/trans-permethrin, and β-cyfluthrin in corn oil. At 1, 2, 4, 8, or 24h after dosing, the motor activity of each animal was assessed and the animals sacrificed. Concentrations of pyrethroids in brain and blood, and the following metabolites: cis-/trans-dichlorovinyl-dimethylcyclopropane-carboxylic acid, 3-phenoxybenzoic acid, 3-phenoxybenzyl alcohol, 4-fluoro-3-phenoxybenzoic acid, and cis-dibromovinyl-dimethylcyclopropane-carboxylic acid were determined using liquid chromatography tandem mass spectrometry (LC-MS/MS). Using this pyrethroid mixture in rats, the results suggest there is greater metabolism of trans-permethrin prior to entering the systemic circulatory system. All pyrethroids had tissue half-lives (t1/2) of less than 5h, excepting esfenvalerate in brain. At early time points, relative pyrethroid brain concentrations approximated their dose mixture proportions and a sigmoidal Emax model described the relationship between motor activity decrease and total pyrethroid brain concentration. In blood, the t1/2's of the cyclopropane metabolites were longer than the phenoxybenzoic metabolites. However, relative to their respective precursors, concentrations of the phenoxybenzoic acids were much higher than concentrations of the cyclopropane metabolites. Brain concentrations of all

  16. LC-MS/MS-based approach for obtaining exposure estimates of metabolites in early clinical trials using radioactive metabolites as reference standards.

    PubMed

    Zhang, Donglu; Raghavan, Nirmala; Chando, Theodore; Gambardella, Janice; Fu, Yunlin; Zhang, Duxi; Unger, Steve E; Humphreys, W Griffith

    2007-12-01

    An LC-MS/MS-based approach that employs authentic radioactive metabolites as reference standards was developed to estimate metabolite exposures in early drug development studies. This method is useful to estimate metabolite levels in studies done with non-radiolabeled compounds where metabolite standards are not available to allow standard LC-MS/MS assay development. A metabolite mixture obtained from an in vivo source treated with a radiolabeled compound was partially purified, quantified, and spiked into human plasma to provide metabolite standard curves. Metabolites were analyzed by LC-MS/MS using the specific mass transitions and an internal standard. The metabolite concentrations determined by this approach were found to be comparable to those determined by valid LC-MS/MS assays. This approach does not requires synthesis of authentic metabolites or the knowledge of exact structures of metabolites, and therefore should provide a useful method to obtain early estimates of circulating metabolites in early clinical or toxicological studies.

  17. The structures of three metabolites of the algal hepatotoxin okadaic acid produced by oxidation with human cytochrome P450

    PubMed Central

    Liu, Li; Guoa, Fujiang; Crain, Sheila; Quilliam, Michael A.; Wang, Xiaotang; Rein, Kathleen S.

    2012-01-01

    Four metabolites of okadaic acid were generated by incubation with human recombinant cytochrome P450 3A4. The structures of two of the four metabolites have been determined by MS/MS experiments and 1D and 2D NMR methods using 94 and 133 μg of each metabolite. The structure of a third metabolite was determined by oxidation to a metabolite of known structure. Like okadaic acid, the metabolites are inhibitors of protein phosphatase PP2A. Although one of the metabolites does have an α,β unsaturated carbonyl with the potential to form adducts with an active site cysteine, all of the metabolites are reversible inhibitors of PP2A. PMID:22608922

  18. Enzymatic sulfation of tocopherols and tocopherol metabolites by human cytosolic sulfotransferases.

    PubMed

    Hashiguchi, Takuyu; Kurogi, Katsuhisa; Sakakibara, Yoichi; Yamasaki, Masao; Nishiyama, Kazuo; Yasuda, Shin; Liu, Ming-Cheh; Suiko, Masahito

    2011-01-01

    Tocopherols are essential micronutrients for mammals widely known as potent lipid-soluble antioxidants that are present in cell membranes. Recent studies have demonstrated that most of the carboxychromanol (CEHC), a tocopherol metabolite, in the plasma exists primarily in sulfate- and glucuronide-conjugated forms. To gain insight into the enzymatic sulfation of tocopherols and their metabolites, a systematic investigation was performed using all 14 known human cytosolic sulfotransferases (SULTs). The results showed that the members of the SULT1 family displayed stronger sulfating activities toward tocopherols and their metabolites. These enzymes showed a substrate preference for γ-tocopherol over α-tocopherol and for γ-CEHC over other CEHCs. Using A549 human lung epithelial cells in a metabolic labeling study, a similar trend in the sulfation of tocopherols and CEHCs was observed. Collectively, the results obtained indicate that SULT-mediated enzymatic sulfation of tocopherols and their metabolites is a significant pathway for regulation of the homeostasis and physiological functions of these important compounds.

  19. Cyanidin-3-glucoside and its phenolic acid metabolites attenuate visible light-induced retinal degeneration in vivo via activation of Nrf2/HO-1 pathway and NF-κB suppression.

    PubMed

    Wang, Yong; Huo, Yazhen; Zhao, Liang; Lu, Feng; Wang, Ou; Yang, Xue; Ji, Baoping; Zhou, Feng

    2016-07-01

    Cyanidin-3-glucoside (C3G) is a major anthocyanin in berries and a potential nutritional supplement for preventing retinal degeneration. However, the protective mechanism of C3G and its metabolites, protocatechuic acid (PCA) and ferulic acid (FA), remain unclear. The molecular mechanisms of C3G and its metabolites against retinal photooxidative damage in vivo are investigated. Pigmented rabbits were orally administered C3G, PCA, and FA (0.11 mmol/kg/day) for 3 weeks. Electroretinography, histological analysis, and TUNEL assay showed that C3G and its metabolites attenuated retinal cell apoptosis. The expression of oxidative stress markers were upregulated after light exposure but attenuated by C3G and FA, which may be attributed to the elevated secretion and expression of heme oxygenase (HO-1) and nuclear factor erythroid-2 related factor 2 (Nrf2). C3G, PCA, and FA attenuated the secretion or expression of inflammation-related genes; FA suppressed nuclear factor kappa B (NF-κB) activation. The treatments attenuated the light-induced changes on certain apoptotic proteins and angiogenesis-related cytokines. C3G and FA reduced light-induced retinal oxidative stress by activating the Nrf2/HO-1 antioxidant pathway. FA attenuated the light-induced retinal inflammation by suppressing NF-κB activation. C3G and its metabolites attenuated the photooxidation-induced apoptosis and angiogenesis in the retina. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Flow rate of transport network controls uniform metabolite supply to tissue

    PubMed Central

    Meigel, Felix J.

    2018-01-01

    Life and functioning of higher organisms depends on the continuous supply of metabolites to tissues and organs. What are the requirements on the transport network pervading a tissue to provide a uniform supply of nutrients, minerals or hormones? To theoretically answer this question, we present an analytical scaling argument and numerical simulations on how flow dynamics and network architecture control active spread and uniform supply of metabolites by studying the example of xylem vessels in plants. We identify the fluid inflow rate as the key factor for uniform supply. While at low inflow rates metabolites are already exhausted close to flow inlets, too high inflow flushes metabolites through the network and deprives tissue close to inlets of supply. In between these two regimes, there exists an optimal inflow rate that yields a uniform supply of metabolites. We determine this optimal inflow analytically in quantitative agreement with numerical results. Optimizing network architecture by reducing the supply variance over all network tubes, we identify patterns of tube dilation or contraction that compensate sub-optimal supply for the case of too low or too high inflow rate. PMID:29720455

  1. Influence of the urine flow rate on some caffeine metabolite ratios used to assess CYP1A2 activity.

    PubMed

    Sinués, Blanca; Fanlo, Ana; Bernal, María Luisa; Mayayo, Esteban; Soriano, María Antonia; Martínez-Ballarin, Enrique

    2002-12-01

    Five established metabolite ratios (MRs) to measure P450 CYP1A2 activity--MR1 (17X + 17U)/137X, MR2 (AFMU + 1X + 1U)/17U, MR3 (17X/137X), MR4 (AFMU + 1X + 1U + 17X + 17U)/137X, and MR5 (AFMU + 1X + 1U)/17X--were calculated in urine 4-5 hours after caffeine intake. First, to assess the potential of omeprazole to induce CYP1A2 activity, a caffeine test was performed in 27 subjects on two occasions: before and after 14 days on omeprazole (20 mg/day). Samples of urine were analyzed by high-performance liquid chromatography (HPLC) to quantify caffeine and metabolites used to calculate the different caffeine MRs. MR1, MR3, and MR4 were enhanced after treatment; the percentage of change was inversely associated with that of the urine flow, with r values of -0.48, -0.49, and -0.47, respectively. However, MR2 or MR5 were not modified. To determine the reason for these contradictory results, the authors analyzed data of metabolites, ratios, and their components (numerators and denominators) from 152 subjects (who underwent one caffeine test) and their relationship with the urinary flow. Caffeine concentration in urine was the only compound nondependent on the urine flow. Consistently, ratios containing caffeine (MR1, MR3, and MR4) were highly influenced by the rate of urine excretion, since the flow dependence of their numerators is not canceled out by that of caffeine in their denominators. The dependency of the caffeine excretion on renal factors may explain the opposite results found with the different ratios in the aforementioned prospective study of drug interaction, the absence of closer correlations of the five MRs to each other, the discrepancies about the type of frequency distribution of the different MRs (either normal or multimodal), and the higher sensitivity of MR2 to detect gender differences in CYP1A2 activity found in this study. In summary, the data clearly emphasize the need for a strict control of the liquid intake to avoid high urine flows when MRs

  2. Environmental monitoring and assessment of antibacterial metabolite producing actinobacteria screened from marine sediments in south coastal regions of Karnataka, India.

    PubMed

    Skariyachan, Sinosh; Garka, Shruthi; Puttaswamy, Sushmitha; Shanbhogue, Shobitha; Devaraju, Raksha; Narayanappa, Rajeswari

    2017-06-01

    Assessment of the therapeutic potential of secondary metabolite producing microorganisms from the marine coastal areas imparts scope and application in the field of environmental monitoring. The present study aims to screen metabolites with antibacterial potential from actionbacteria associated with marine sediments collected from south coastal regions of Karnataka, India. The actinobacteria were isolated and characterized from marine sediments by standard protocol. The metabolites were extracted, and antibacterial potential was analyzed against eight hospital associated bacteria. The selected metabolites were partially characterized by proximate analysis, SDS-PAGE, and FTIR-spectroscopy. The antibiogram of the test clinical isolates revealed that they were emerged as multidrug-resistant strains (P ≤ 0.05). Among six actinobacteria (IS1-1S6) screened, 100 μl -1 metabolite from IS1 showed significant antibacterial activities against all the clinical isolates except Pseudomonas aeruginosa. IS2 demonstrated antimicrobial potential towards Proteus mirabilis, Streptococcus pyogenes, and Escherichia coli. The metabolite from IS3 showed activity against Strep. pyogenes and E. coli. The metabolites from IS4, IS5, and IS6 exhibited antimicrobial activities against Ps. aeruginosa (P ≤ 0.05). The two metabolites that depicted highest antibacterial activities against the test strains were suggested to be antimicrobial peptides with low molecular weight. These isolates were characterized and designated as Streptomyces sp. strain mangaluru01 and Streptomyces sp. mangaloreK01 by 16S ribosomal DNA (rDNA) sequencing. This study suggests that south coastal regions of Karnataka, India, are one of the richest sources of antibacterial metabolites producing actinobacteria and monitoring of these regions for therapeutic intervention plays profound role in healthcare management.

  3. Effects of Secondary Metabolites of Permafrost Bacillus sp. on Cytokine Synthesis by Human Peripheral Blood Mononuclear Cells.

    PubMed

    Kalenova, L F; Kolyvanova, S S; Bazhin, A S; Besedin, I M; Mel'nikov, V P

    2017-06-01

    We studied the effects of secondary metabolites of Bacillus sp. isolated from late Neogene permafrost on secretion of proinflammatory (TNF-α, IL-1β, IL-8, IL-2, and IFNγ) and antiinflammatory (IL-4 and IL-10) cytokines by human peripheral blood mononuclear cells. It was found that metabolites of Bacillus sp. produced more potent effect on cytokine secretion than mitogen phytohemagglutinin and metabolites of Bacillus cereus, medicinal strain IP5832. Activity of metabolites depended on the temperature of bacteria incubation. "Cold" metabolites of Bacillus sp. (isolated at -5°C) primarily induced Th1-mediated secretion of IFNγ, while "warm" metabolites (obtained at 37°C) induced Th2-mediated secretion of IL-4. The results suggest that Bacillus sp. metabolites are promising material for the development of immunomodulating drugs.

  4. Genetic diversity among pandemic 2009 influenza viruses isolated from a transmission chain

    PubMed Central

    2013-01-01

    Background Influenza viruses such as swine-origin influenza A(H1N1) virus (A(H1N1)pdm09) generate genetic diversity due to the high error rate of their RNA polymerase, often resulting in mixed genotype populations (intra-host variants) within a single infection. This variation helps influenza to rapidly respond to selection pressures, such as those imposed by the immunological host response and antiviral therapy. We have applied deep sequencing to characterize influenza intra-host variation in a transmission chain consisting of three cases due to oseltamivir-sensitive viruses, and one derived oseltamivir-resistant case. Methods Following detection of the A(H1N1)pdm09 infections, we deep-sequenced the complete NA gene from two of the oseltamivir-sensitive virus-infected cases, and all eight gene segments of the viruses causing the remaining two cases. Results No evidence for the resistance-causing mutation (resulting in NA H275Y substitution) was observed in the oseltamivir-sensitive cases. Furthermore, deep sequencing revealed a subpopulation of oseltamivir-sensitive viruses in the case carrying resistant viruses. We detected higher levels of intra-host variation in the case carrying oseltamivir-resistant viruses than in those infected with oseltamivir-sensitive viruses. Conclusions Oseltamivir-resistance was only detected after prophylaxis with oseltamivir, suggesting that the mutation was selected for as a result of antiviral intervention. The persisting oseltamivir-sensitive virus population in the case carrying resistant viruses suggests either that a small proportion survive the treatment, or that the oseltamivir-sensitive virus rapidly re-establishes itself in the virus population after the bottleneck. Moreover, the increased intra-host variation in the oseltamivir-resistant case is consistent with the hypothesis that the population diversity of a RNA virus can increase rapidly following a population bottleneck. PMID:23587185

  5. Fungal cell-wall lytic enzymes, antifungal metabolite(s) production, and characterization from Streptomyces exfoliatus MT9 for controlling fruit-rotting fungi.

    PubMed

    Choudhary, Bharti; Nagpure, Anand; Gupta, Rajinder K

    2014-12-01

    An antifungal actinomycete strain MT9 was isolated from Loktak Lake, Manipur, India and its cultural characteristics, fatty acid methyl ester, 16S rRNA gene analysis suggests that strain MT9 is identical to Streptomyces exfoliatus. Strain MT9 displayed strong and broad-spectrum antagonism towards several fruit-rotting fungi by mycelial growth suppression. Crude fungal cell-wall lytic enzymes, i.e., chitinase, β-1,3-glucanase, and protease produced by S. exfoliatus MT9 were optimally active at pH 8.0 and 50 °C, pH 5.0 and 60 °C, pH 9.0 and 70 °C, respectively. All three mycolytic enzymes had good stability over a wide pH range of 5.0-10.0, with protease being more thermostable than both chitinase and β-1,3-glucanase. Interestingly zymogram analysis revealed that S. exfoliatus MT9 secretes six distinct chitinase isoenzymes with approximate molecular weights of 9.42, 13.93, 27.87, 36.43, 54.95, 103.27 kDa, six active protease isoenzymes with apparent molecular weights of 12.45, 30.20, 37.45, 46.32, 52.46, 131.46 kDa, and an active band of 119.39 kDa as β-1,3-glucanase enzyme. Extracellular fluid and its organic solvent extracts also exhibited inhibitory activity to various fruit-rotting fungi. The MIC value of n-butanol extract was 2-25 µg/ml against tested fruit-rotting fungi. Antifungal secondary metabolite(s) was found to be polyene in nature. To the best of our knowledge, this is the first report on extracellular production of fungal cell-wall lytic enzymes and antifungal metabolites by bioactive S. exfoliatus MT9 under submerged fermentation. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Experiment requirements: Vitamin D metabolites and bone demineralization, Spacelab 2, experiment no. 1

    NASA Technical Reports Server (NTRS)

    Schnoes, H. K.; Holton, E. M.; Thirolf, R. G.

    1978-01-01

    As a contribution toward an understanding of the molecular basis of bone loss, mineral imbalance, and increasing fecal calcium under conditions of prolonged space flight, the blood levels of biologically active vitamin D metabolites of flight crew members will be quantitatively measured. Prior to the mission, the refinement of existing and the development of new techniques for the assay of all vitamin D metabolites will provide an arsenal of methods suitable for a wide range of metabolite levels. In terms of practical application, the analysis of human and animal plasma samples, Spacelab crew plasma samples, and flight hardware are envisioned.

  7. Enzyme inhibitory metabolites from endophytic Penicillium citrinum isolated from Boswellia sacra.

    PubMed

    Ali, Sajid; Khan, Abdul Latif; Ali, Liaqat; Rizvi, Tania Shamim; Khan, Sumera Afzal; Hussain, Javid; Hamayun, Muhammad; Al-Harrasi, Ahmed

    2017-07-01

    Fungal endophytes establish an important niche within the host plant through the secretion of chemical constituents. Isolation of bioactive metabolites could be a vital source for inhibiting the function of enzymes such as α-glucosidase and urease. The present study aimed to elucidate the potential of endophytes associated with Boswellia sacra through bioassay-guided isolation and identification of secondary metabolites with enzyme inhibitory ability. Endophytic fungal strains viz. Penicillium citrinum, P. spinulosum, Fusarium oxysporum, Alternaria alternata and Aspergillus caespitosus were identified through genomic DNA extraction, PCR amplification, sequencing and phylogenetic analysis. The enzymes inhibition analysis of the ethyl acetate extract from pure cultures suggested that P. citrinum possess significantly higher enzyme inhibitory activities compared to other strains. The active strain was subjected to chromatographic isolation and nuclear magnetic resonance methods to identify bioactive compounds. The bioactive extracts resulted in the isolation of 11-oxoursonic acid benzyl ester (1), n-nonane (2), 3-decene-1-ol (3), 2-Hydroxyphenyl acetic acid (4), and Glochidacuminosides A (5). Among pure compound, 11-oxoursonic acid benzyl ester (1) showed significantly higher enzyme inhibition activity compared to other metabolites. Our results suggest that the endophytic microorganism associated with the arid-land tree can offer a rich source of biologically active chemical constituents that could help discover lead drugs for enzyme inhibition.

  8. Correlation between species-specific metabolite profiles and bioactivities of blueberries (Vaccinium spp.).

    PubMed

    Lee, Sarah; Jung, Eun Sung; Do, Seon-Gil; Jung, Ga-Young; Song, Gwanpil; Song, Jung-Min; Lee, Choong Hwan

    2014-03-05

    Metabolite profiling of three blueberry species (Vaccinium bracteatum Thunb., V. oldhamii Miquel., and V. corymbosum L.) was performed using gas chromatography-time-of-flight-mass spectrometry (GC-TOF-MS) and ultraperformance liquid chromatography-quadrupole-time-of-flight-mass spectrometry (UPLC-Q-TOF-MS) combined multivariate analysis. Partial least-squares discriminant analysis clearly showed metabolic differences among species. GC-TOF-MS analysis revealed significant differences in amino acids, organic acids, fatty acids, sugars, and phenolic acids among the three blueberry species. UPLC-Q-TOF-MS analysis indicated that anthocyanins were the major metabolites distinguishing V. bracteatum from V. oldhamii. The contents of anthocyanins such as glycosides of cyanidin were high in V. bracteatum, while glycosides of delphinidin, petunidin, and malvidin were high in V. oldhamii. Antioxidant activities assessed using ABTS and DPPH assays showed the greatest activity in V. oldhamii and revealed the highest correlation with total phenolic, total flavonoid, and total anthocyanin contents and their metabolites.

  9. A review of the volatile metabolites of fungi found on wood substrates.

    PubMed

    McAfee, B J; Taylor, A

    1999-01-01

    The holdings of eight collections of fungi have been examined for organisms isolated from wood and/or trees. Further selection of these fungi has been made according to their reported ability to produce volatile, biologically active metabolites. It is emphasized that the isolates in the collections do not necessarily produce such metabolites. The list of fungi fulfilling these conditions is slightly augmented by reports we have found in the literature, where the fungi concerned have not yet been deposited. The biochemistry of these compounds is considered with particular emphasis on their biosynthesis including that by Homo sapiens. The physiological and toxicological activity of these metabolites is reviewed especially with reference to their potential role in the complex symbioses existent in, for example, a tree. The review concludes with a discussion of areas of botany deserving increased attention in the hope that this will stimulate further work. The statements in the review are based on 173 references.

  10. Secondary Metabolites from Polar Organisms

    PubMed Central

    Tian, Yuan; Li, Yan-Ling; Zhao, Feng-Chun

    2017-01-01

    Polar organisms have been found to develop unique defences against the extreme environment environment, leading to the biosynthesis of novel molecules with diverse bioactivities. This review covers the 219 novel natural products described since 2001, from the Arctic and the Antarctic microoganisms, lichen, moss and marine faunas. The structures of the new compounds and details of the source organism, along with any relevant biological activities are presented. Where reported, synthetic and biosynthetic studies on the polar metabolites have also been included. PMID:28241505

  11. Aquatic toxicity of the macrolide antibiotic clarithromycin and its metabolites.

    PubMed

    Baumann, Michaela; Weiss, Klaus; Maletzki, Dirk; Schüssler, Walter; Schudoma, Dieter; Kopf, Willi; Kühnen, Ute

    2015-02-01

    The human macrolide antibiotic clarithromycin is widespread in surface waters. Our study shows that its major metabolite 14-hydroxy(R)-clarithromycin is found in surface waters in comparable amounts. This metabolite is known to be pharmacologically active. Additionally, clarithromycin is partly metabolised to N-desmethyl-clarithromycin, which has no antimicrobial activity. For clarithromycin, some ecotoxicological studies on aquatic organisms have been published. However, many of them are not conform with the scientific principles as given in the "Technical guidance for deriving environmental quality standards" (TGD-EQS), because numerous studies were poorly documented and the methods did not contain analytical measurements confirming that the exposure concentrations were in the range of ± 20% of the nominal concentrations. Ecotoxicological effects of clarithromycin and its two metabolites on the zebrafish Danio rerio (embryo test), the microcrustacean Daphnia magna, the aquatic monocotyledonous macrophyte Lemna minor, the freshwater green alga Desmodesmus subspicatus (Chlorophyta) and the cyanobacterium Anabaena flosaquae were investigated in compliance with the TGD-EQS. Environmental risk assessment was performed using ErC10 values of Anabaena, the species most sensitive to clarithromycin and 14-hydroxy(R)-clarithromycin in our testing. Based oncomparable toxicity and similar concentrations of clarithromycin and its active metabolite 14-hydroxy(R)-clarithromycin in surface waters, an additional multiplication factor of 2 to the assessment factor of 10 on the ErC10 of clarithromycin should be used. Consequently, a freshwater quality standard of 0.130 μg L(-1) is proposed for clarithromycin as the "lead substance". Taking this additional multiplication factor of 2 into account, single monitoring of clarithromycin may be sufficient, in order to reduce the number of substances listed for routine monitoring programs. Copyright © 2014 Elsevier Ltd. All rights

  12. The metabolite profiling of coastal coccolithophorid species Pleurochrysis carterae (Haptophyta)

    NASA Astrophysics Data System (ADS)

    Zhou, Chengxu; Luo, Jie; Ye, Yangfang; Yan, Xiaojun; Liu, Baoning; Wen, Xin

    2016-07-01

    Pleurochrysis carterae is a calcified coccolithophorid species that usually blooms in the coastal area and causes aquaculture losses. The cellular calcification, blooming and many other critical species specific eco-physiological processes are closely related to various metabolic pathways. The purpose of this study is to apply the unbiased and non-destructive method of nuclear magnetic resonance (NMR) to detect the unknown holistic metabolite of P. carterae. The results show that NMR spectroscopic method is practical in the analysis of metabolites of phytoplankton. The metabolome of P. carterae was dominated by 26 metabolites involved in a number of different primary and secondary metabolic pathways. Organic acids and their derivatives, amino acids, sugars, nucleic aides were mainly detected. The abundant metabolites are that closely related to the process of cellular osmotic adjustment, which possibly reflect the active ability of P. carterae to adapt to the versatile coastal niche. DMSP (dimethylsulphoniopropionate) was the most dominant metabolite in P. carterae, up to 2.065±0.278 mg/g lyophilized cells, followed by glutamate and lactose, the contents were 0.349±0.035 and 0.301±0.073 mg/g lyophilized cells respectively. Other metabolites that had the content ranged between 0.1-0.2 mg/g lyophilized cells were alanine, isethionate and arabinose. Amino acid (valine, phenylalanine, isoleucine, tyrosine), organic acid salts (lactate, succinate), scyllitol and uracil had content ranged from 0.01 to below 0.1 mg/g lyophilized cells. Trigonelline, fumarate and formate were detected in very low content (only thousandths of 1 mg per gram of lyophilized cells or below). Our results of the holistic metabolites of P. carterae are the basic references for the further studies when multiple problems will be addressed to this notorious blooming calcifying species.

  13. Biotransformation of a potent anabolic steroid, mibolerone, with Cunninghamella blakesleeana, C. echinulata, and Macrophomina phaseolina, and biological activity evaluation of its metabolites.

    PubMed

    Siddiqui, Mahwish; Ahmad, Malik Shoaib; Wahab, Atia-Tul-; Yousuf, Sammer; Fatima, Narjis; Naveed Shaikh, Nimra; Rahman, Atta-Ur-; Choudhary, M Iqbal

    2017-01-01

    Seven metabolites were obtained from the microbial transformation of anabolic-androgenic steroid mibolerone (1) with Cunninghamella blakesleeana, C. echinulata, and Macrophomina phaseolina. Their structures were determined as 10β,17β-dihydroxy-7α,17α-dimethylestr-4-en-3-one (2), 6β,17β-dihydroxy-7α,17α-dimethylestr-4-en-3-one (3), 6β,10β,17β-trihydroxy-7α,17α-dimethylestr-4-en-3-one (4), 11β,17β-dihydroxy-(20-hydroxymethyl)-7α,17α-dimethylestr-4-en-3-one (5), 1α,17β-dihydroxy-7α,17α-dimethylestr-4-en-3-one (6), 1α,11β,17β-trihydroxy-7α,17α-dimethylestr-4-en-3-one (7), and 11β,17β-dihydroxy-7α,17α-dimethylestr-4-en-3-one (8), on the basis of spectroscopic studies. All metabolites, except 8, were identified as new compounds. This study indicates that C. blakesleeana, and C. echinulata are able to catalyze hydroxylation at allylic positions, while M. phaseolina can catalyze hydroxylation of CH2 and CH3 groups of substrate 1. Mibolerone (1) was found to be a moderate inhibitor of β-glucuronidase enzyme (IC50 = 42.98 ± 1.24 μM) during random biological screening, while its metabolites 2-4, and 8 were found to be inactive. Mibolerone (1) was also found to be significantly active against Leishmania major promastigotes (IC50 = 29.64 ± 0.88 μM). Its transformed products 3 (IC50 = 79.09 ± 0.06 μM), and 8 (IC50 = 70.09 ± 0.05 μM) showed a weak leishmanicidal activity, while 2 and 4 were found to be inactive. In addition, substrate 1 (IC50 = 35.7 ± 4.46 μM), and its metabolite 8 (IC50 = 34.16 ± 5.3 μM) exhibited potent cytotoxicity against HeLa cancer cell line (human cervical carcinoma). Metabolite 2 (IC50 = 46.5 ± 5.4 μM) also showed a significant cytotoxicity, while 3 (IC50 = 107.8 ± 4.0 μM) and 4 (IC50 = 152.5 ± 2.15 μM) showed weak cytotoxicity against HeLa cancer cell line. Compound 1 (IC50 = 46.3 ± 11.7 μM), and its transformed products 2 (IC50 = 43.3 ± 7.7 μM), 3 (IC50 = 65.6 ± 2.5 μM), and 4 (IC50 = 89.4 ± 2.7

  14. Isolation and Identification of Twelve Metabolites of Isocorynoxeine in Rat Urine and their Neuroprotective Activities in HT22 Cell Assay

    PubMed Central

    Qi, Wen; Chen, Fangfang; Sun, Jiahong; Simpkins, James W.; Yuan, Dan

    2015-01-01

    Isocorynoxeine, one of the major alkaloids from Uncaria Hook, shows the effects of lowering blood pressure, vasodilatation, and protection against ischemia-induced neuronal damage. In this paper, the metabolism of isocorynoxeine was investigated in rats. Twelve metabolites and the parent drug were isolated by using solvent extraction and repeated chromatographic methods, and determined by spectroscopic methods including UV, MS, NMR, and CD experiments. Seven new compounds were identified as 11-hydroxyisocorynoxeine, 5-oxoisocorynoxeinic acid-22-O-β-D-glucuronide, 10-hydroxyisocorynoxeine, 17-O-demethyl-16,17-dihydro-5-oxoisocorynoxeine, 5-oxoisocorynoxeinic acid, 21-hydroxy-5-oxoisocorynoxeine, and oxireno[18,19]-5-oxoisocorynoxeine, together with six known compounds identified as isocorynoxeine, 18,19-dehydrocorynoxinic acid, 18,19-dehydrocorynoxinic acid B, corynoxeine, isocorynoxeine-N-oxide, and corynoxeine-N-oxide. Possible metabolic pathways of isocorynoxeine are proposed. Furthermore, the activity assay for the parent drug and some of its metabolites showed that isocorynoxeine exhibited a significant neuroprotective effect against glutamate-induced HT22 cell death at the maximum concentration. However, little or weak neuroprotective activities were observed for M-3, M-6, M-7, and M-10. Our present study is important to further understand their metabolic fate and disposition in humans. PMID:25519834

  15. Accuracy investigation of phthalate metabolite standards.

    PubMed

    Langlois, Éric; Leblanc, Alain; Simard, Yves; Thellen, Claude

    2012-05-01

    Phthalates are ubiquitous compounds whose metabolites are usually determined in urine for biomonitoring studies. Following suspect and unexplained results from our laboratory in an external quality-assessment scheme, we investigated the accuracy of all phthalate metabolite standards in our possession by comparing them with those of several suppliers. Our findings suggest that commercial phthalate metabolite certified solutions are not always accurate and that lot-to-lot discrepancies significantly affect the accuracy of the results obtained with several of these standards. These observations indicate that the reliability of the results obtained from different lots of standards is not equal, which reduces the possibility of intra-laboratory and inter-laboratory comparisons of results. However, agreements of accuracy have been observed for a majority of neat standards obtained from different suppliers, which indicates that a solution to this issue is available. Data accuracy of phthalate metabolites should be of concern for laboratories performing phthalate metabolite analysis because of the standards used. The results of our investigation are presented from the perspective that laboratories performing phthalate metabolite analysis can obtain accurate and comparable results in the future. Our findings will contribute to improving the quality of future phthalate metabolite analyses and will affect the interpretation of past results.

  16. A general method to correct PET data for tissue metabolites using a dual-scan approach.

    PubMed

    Gunn, R N; Yap, J T; Wells, P; Osman, S; Price, P; Jones, T; Cunningham, V J

    2000-04-01

    This article presents and analyses a general method of correcting for the presence of radiolabeled metabolites from a parent radiotracer in tissue during PET scanning. The method is based on a dual-scan approach, i.e., parent scan together with an independent supplementary scan in which the radiolabeled metabolite of interest itself is administered. The method corrects for the presence of systemically derived radiolabeled metabolite delivered to the tissues of interest through the blood. Data from the supplementary scan are analyzed to obtain the tissue impulse response function for the metabolite. The time course of the radiolabeled metabolite in plasma in the parent scan is convolved with its tissue impulse response function to derive a correction term. This is not a simple subtraction technique but 1 that takes account of the different time-activity curves of the radiolabeled metabolite in the 2 scans. The method, its implications, and its limitations are discussed with respect to [11C]thymidine and its principal metabolite 11CO2. The general method, based on a dual-scan approach, can be used to correct for radiolabeled metabolites in tissues of interest during PET scanning. The correction accounts for radiolabeled metabolites that are derived systemically and delivered to the tissues of interest through the blood.

  17. Bioavailability of Bergamot (Citrus bergamia) Flavanones and Biological Activity of Their Circulating Metabolites in Human Pro-Angiogenic Cells

    PubMed Central

    Spigoni, Valentina; Fantuzzi, Federica; Tassotti, Michele; Brighenti, Furio; Bonadonna, Riccardo C.; Dei Cas, Alessandra

    2017-01-01

    Myeloid angiogenic cells (MACs) play a key role in endothelial repairing processes and functionality but their activity may be impaired by the lipotoxic effects of some molecules like stearic acid (SA). Among the dietary components potentially able to modulate endothelial function in vivo, (poly)phenolic compounds represent serious candidates. Here, we apply a comprehensive multidisciplinary approach to shed light on the prospects of Bergamot (Citrus bergamia), a citrus fruit rich in flavanones and other phenolic compounds, in the framework of lipotoxicity-induced MACs impairment. The flavanone profile of bergamot juice was characterized and 16 compounds were identified, with a new 3-hydroxy-3-methylglutaryl (HMG) flavanone, isosakuranetin-7-O-neohesperidoside-6″-O-HMG, described for the first time. Then, a pilot bioavailability study was conducted in healthy volunteers to assess the circulating flavanone metabolites in plasma and urine after consumption of bergamot juice. Up to 12 flavanone phase II conjugates (sulfates and glucuronides of hesperetin, naringenin and eriodyctiol) were detected and quantified. Finally, the effect of some of the metabolites identified in vivo, namely hesperetin-7-O-glucuronide, hesperetin-3′-O-glucuronide, naringenin-7-O-glucuronide and naringenin-4′-O-glucuronide, was tested, at physiological concentrations, on gene expression of inflammatory markers and apoptosis in MACs exposed to SA. Under these conditions, naringenin-4′-O-glucuronide and hesperetin-7-O-glucuronide were able to modulate inflammation, while no flavanone glucuronide was effective in curbing stearate-induced lipoapoptosis. These results demonstrate that some flavanone metabolites, derived from the in vivo transformation of bergamot juice phenolics in humans, may mitigate stearate-induced inflammation in MACs. PMID:29211032

  18. Bioavailability of Bergamot (Citrus bergamia) Flavanones and Biological Activity of Their Circulating Metabolites in Human Pro-Angiogenic Cells.

    PubMed

    Spigoni, Valentina; Mena, Pedro; Fantuzzi, Federica; Tassotti, Michele; Brighenti, Furio; Bonadonna, Riccardo C; Del Rio, Daniele; Dei Cas, Alessandra

    2017-12-06

    Myeloid angiogenic cells (MACs) play a key role in endothelial repairing processes and functionality but their activity may be impaired by the lipotoxic effects of some molecules like stearic acid (SA). Among the dietary components potentially able to modulate endothelial function in vivo, (poly)phenolic compounds represent serious candidates. Here, we apply a comprehensive multidisciplinary approach to shed light on the prospects of Bergamot ( Citrus bergamia ), a citrus fruit rich in flavanones and other phenolic compounds, in the framework of lipotoxicity-induced MACs impairment. The flavanone profile of bergamot juice was characterized and 16 compounds were identified, with a new 3-hydroxy-3-methylglutaryl (HMG) flavanone, isosakuranetin-7- O -neohesperidoside-6″- O -HMG, described for the first time. Then, a pilot bioavailability study was conducted in healthy volunteers to assess the circulating flavanone metabolites in plasma and urine after consumption of bergamot juice. Up to 12 flavanone phase II conjugates (sulfates and glucuronides of hesperetin, naringenin and eriodyctiol) were detected and quantified. Finally, the effect of some of the metabolites identified in vivo, namely hesperetin-7- O -glucuronide, hesperetin-3'- O -glucuronide, naringenin-7- O -glucuronide and naringenin-4'- O -glucuronide, was tested, at physiological concentrations, on gene expression of inflammatory markers and apoptosis in MACs exposed to SA. Under these conditions, naringenin-4'- O -glucuronide and hesperetin-7- O -glucuronide were able to modulate inflammation, while no flavanone glucuronide was effective in curbing stearate-induced lipoapoptosis. These results demonstrate that some flavanone metabolites, derived from the in vivo transformation of bergamot juice phenolics in humans, may mitigate stearate-induced inflammation in MACs.

  19. Antiproliferative, Antibacterial and Antifungal Activity of the Lichen Xanthoria parietina and Its Secondary Metabolite Parietin

    PubMed Central

    Basile, Adriana; Rigano, Daniela; Loppi, Stefano; Di Santi, Annalisa; Nebbioso, Angela; Sorbo, Sergio; Conte, Barbara; Paoli, Luca; De Ruberto, Francesca; Molinari, Anna Maria; Altucci, Lucia; Bontempo, Paola

    2015-01-01

    Lichens are valuable natural resources used for centuries throughout the world as medicine, food, fodder, perfume, spices and dyes, as well as for other miscellaneous purposes. This study investigates the antiproliferative, antibacterial and antifungal activity of the acetone extract of the lichen Xanthoria parietina (Linnaeus) Theodor Fries and its major secondary metabolite, parietin. The extract and parietin were tested for antimicrobial activity against nine American Type Culture Collection standard and clinically isolated bacterial strains, and three fungal strains. Both showed strong antibacterial activity against all bacterial strains and matched clinical isolates, particularly against Staphylococcus aureus from standard and clinical sources. Among the fungi tested, Rhizoctonia solani was the most sensitive. The antiproliferative effects of the extract and parietin were also investigated in human breast cancer cells. The extract inhibited proliferation and induced apoptosis, both effects being accompanied by modulation of expression of cell cycle regulating genes such as p16, p27, cyclin D1 and cyclin A. It also mediated apoptosis by activating extrinsic and intrinsic cell death pathways, modulating Tumor Necrosis Factor-related apoptosis-inducing ligand (TRAIL) and B-cell lymphoma 2 (Bcl-2), and inducing Bcl-2-associated agonist of cell death (BAD) phosphorylation. Our results indicate that Xanthoria parietina is a major potential source of antimicrobial and anticancer substances. PMID:25860944

  20. Enhanced metabolite generation

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

    Chidambaram, Devicharan

    The present invention relates to the enhanced production of metabolites by a process whereby a carbon source is oxidized with a fermentative microbe in a compartment having a portal. An electron acceptor is added to the compartment to assist the microbe in the removal of excess electrons. The electron acceptor accepts electrons from the microbe after oxidation of the carbon source. Other transfers of electrons can take place to enhance the production of the metabolite, such as acids, biofuels or brewed beverages.

  1. Colon cancer chemopreventive effects of baicalein, an active enteric microbiome metabolite from baicalin

    PubMed Central

    WANG, CHONG-ZHI; ZHANG, CHUN-FENG; CHEN, LINA; ANDERSON, SAMANTHA; LU, FANG; YUAN, CHUN-SU

    2015-01-01

    Baicalin is a major constituent of Scutellaria baicalensis, which is a commonly used herbal medicine in many Asian countries. After oral ingestion, intestinal micro-biota metabolism may change parent compound's structure and its biological activities. However, whether baicalin can be metabolized by enteric microbiota and the related anti-cancer activity is not clear. In this study, using human enteric microbiome incubation and HPLC analysis, we observed that baicalin can be quickly converted to baicalein. We compared the antiproliferative effects of baicalin and baicalein using a panel of human cancer cell lines, including three human colorectal cancer (CRC) cell lines. In vitro antiproliferative effects on CRC cells were verified using an in vivo xenograft nude mouse model. Baicalin showed limited antiproliferative effects on some of these cancer cell lines. Baicalein, however, showed significant antiproliferative effects in all the tested cancer cell lines, especially on HCT-116 human colorectal cancer cells. In vivo antitumor results supported our in vitro data. We demonstrated that baicalein exerts potent S phase cell cycle arrest and pro-apoptotic effects in HCT-116 cells. Baicalein induced the activation of caspase 3 and 9. The in silico modeling suggested that baicalein forms hydrogen bonds with residues Ser251 and Asp253 at the active site of caspase 3, while interactions with residues Leu227 and Asp228 in caspase 9 through its hydroxyl groups. Data from this study suggested that baicalein is a potent anticancer metabolite derived from S. baicalensis. Enteric microbiota play a key role in the colon cancer chemoprevention of S. baicalensis. PMID:26398706

  2. Behavioral characterization of 2-O-desmethyl and 5-O-desmethyl metabolites of the phenylethylamine hallucinogen DOM.

    PubMed

    Eckler, J R; Chang-Fong, J; Rabin, R A; Smith, C; Teitler, M; Glennon, R A; Winter, J C

    2003-07-01

    The present investigation was undertaken to test the hypothesis that known metabolites of the phenylethylamine hallucinogen 1-(2,5-dimethoxy-4-methylphenyl)-2-aminopropane (DOM) are pharmacologically active. This hypothesis was tested by evaluating the ability of racemic DOM metabolites 2-O-desmethyl DOM (2-DM-DOM) and 5-O-desmethyl DOM (5-DM-DOM) to substitute for the stimulus properties of (+)lysergic acid diethylamide (LSD). The data indicate that both metabolites are active in LSD-trained subjects and are significantly inhibited by the selective 5-HT(2A) receptor antagonist M100907. Full generalization of LSD to both 2-DM-DOM and 5-DM-DOM occurred, and 5-DM-DOM was slightly more potent than 2-DM-DOM. Similarly, 5-DM-DOM had a slightly higher affinity than 2-DM-DOM for both 5-HT(2A) and 5-HT(2C) receptors. Additionally, it was of interest to determine if the formation of active metabolite(s) resulted in a temporal delay associated with maximal stimulus effects of DOM. We postulated that if metabolite formation resulted in the aforementioned delay, direct administration of the metabolites might result in maximally stable stimulus effects at an earlier pretreatment time. This hypothesis was tested by evaluating (1) the time point at which DOM produces the greatest degree of LSD-appropriate responding, (2) the involvement of 5-HT(2A) receptor in the stimulus effects of DOM at various pretreatment times by administration of M100907 and (3) the ability of 2-DM-DOM and 5-DM-DOM to substitute for the stimulus properties of LSD using either 15- or 75-min pretreatment time. The data indicate that (a) the DOM stimulus produces the greatest degree of LSD-appropriate responding at the 75-min time point in comparison with earlier pretreatment times and (b) the stimulus effects of DOM are differentially antagonized by M100907 and this effect is a function of DOM pretreatment time prior to testing. Both 2-DM-DOM and 5-DM-DOM were found to be most active, at all doses tested

  3. Cytotoxic Cytochalasins and Other Metabolites from Xylariaceae sp. FL0390, a Fungal Endophyte of Spanish Moss.

    PubMed

    Xu, Ya-Ming; Bashyal, Bharat P; Liu, Mangping X; Espinosa-Artiles, Patricia; U'Ren, Jana M; Arnold, A Elizabeth; Gunatilaka, A A Leslie

    2015-10-01

    Two new metabolites, 6-oxo-12-norcytochalasin D (1) and 4,5-di-isobutyl-2(1H)-pyrimidinone (2), together with seven known metabolites, cytochalasins D (3), Q (4), and N (5), 12-hydroxyzygosporin G (6), heptelidic acid chlorohydrin (7), (+)-heptelidic acid (8), and trichoderonic acid A (9), were isolated from Xylariaceae sp. FL0390, a fungal endophyte inhabiting Spanish moss, Tillandsia usneoides. Metabolite 1 is the first example of a 12-norcytochalasin. All metabolites, except 2 and 9, showed cytotoxic activity in a panel of five human tumor cell lines with IC50S of 0.2-5.0 μM.

  4. Characterization of proflavine metabolites in rainbow trout.

    PubMed

    Yu, Z; Hayton, W L; Chan, K K

    1997-04-01

    Proflavine (3,6-diaminoacridine) has potential for use as an antiinfective in fish, and its metabolism by rainbow trout was therefore studied. Fourteen hours after intraarterial bolus administration of 10 mg/kg of proflavine, three metabolites were found in liver and bile, and one metabolite was found in plasma using reversed-phase HPLC with UV detection at 262 nm. Treatment with hydrochloric acid converted the three metabolites to proflavine, which suggested that the metabolites were proflavine conjugates. Treatment with beta-glucuronidase and saccharic acid 1,4-lactone, a specific beta-glucuronidase inhibitor, revealed that two metabolites were proflavine glucuronides. For determination of UV-VIS absorption and mass spectra, HPLC-purified metabolites were isolated from liver. Data from these experiments suggested that the proflavine metabolites were 3-N-glucuronosyl proflavine (PG), 3-N-glucuronosyl,6-N-acetyl proflavine (APG), and 3-N-acetylproflavine (AP). The identities of the metabolites were verified by chemical synthesis. When synthetic PG and AP were compared with the two metabolites isolated from trout, they had the same molecular weight as determined by matrix-assisted, laser desorption ionization, time-of-flight MS. In addition, they coeluted on HPLC under different mobile phase conditions. Finally, the in vitro incubation with liver subcellular preparations confirmed this characterization and provided the evidence that APG can be formed by glucuronidation of AP or acetylation of PG.

  5. Central activation, metabolites, and calcium handling during fatigue with repeated maximal isometric contractions in human muscle.

    PubMed

    Cairns, Simeon P; Inman, Luke A G; MacManus, Caroline P; van de Port, Ingrid G L; Ruell, Patricia A; Thom, Jeanette M; Thompson, Martin W

    2017-08-01

    To determine the roles of calcium (Ca 2+ ) handling by sarcoplasmic reticulum (SR) and central activation impairment (i.e., central fatigue) during fatigue with repeated maximal voluntary isometric contractions (MVC) in human muscles. Contractile performance was assessed during 3 min of repeated MVCs (7-s contraction, 3-s rest, n = 17). In ten participants, in vitro SR Ca 2+ -handling, metabolites, and fibre-type composition were quantified in biopsy samples from quadriceps muscle, along with plasma venous [K + ]. In 11 participants, central fatigue was compared using tetanic stimulation superimposed on MVC in quadriceps and adductor pollicis muscles. The decline of peak MVC force with fatigue was similar for both muscles. Fatigue resistance correlated directly with % type I fibre area in quadriceps (r = 0.77, P = 0.009). The maximal rate of ryanodine-induced Ca 2+ -release and Ca 2+ -uptake fell by 31 ± 26 and 28 ± 13%, respectively. The tetanic force depression was correlated with the combined reduction of ATP and PCr, and increase of lactate (r = 0.77, P = 0.009). Plasma venous [K + ] increased from 4.0 ± 0.3 to 5.4 ± 0.8 mM over 1-3-min exercise. Central fatigue occurred during the early contractions in the quadriceps in 7 out of 17 participants (central activation ratio fell from 0.98 ± 0.05 to 0.86 ± 0.11 at 1 min), but dwindled at exercise cessation. Central fatigue was seldom apparent in adductor pollicis. Fatigue with repeated MVC in human limb muscles mainly involves peripheral aspects which include impaired SR Ca 2+ -handling and we speculate that anaerobic metabolite changes are involved. A faster early force loss in quadriceps muscle with some participants is attributed to central fatigue.

  6. Chemosensation of Bacterial Secondary Metabolites Modulates Neuroendocrine Signaling and Behavior of C. elegans

    PubMed Central

    Meisel, Joshua D.; Panda, Oishika; Mahanti, Parag; Schroeder, Frank C.; Kim, Dennis H.

    2014-01-01

    Summary Discrimination among pathogenic and beneficial microbes is essential for host organism immunity and homeostasis. Here, we show that chemosensory detection of two secondary metabolites produced by Pseudomonas aeruginosa modulates a neuroendocrine signaling pathway that promotes avoidance behavior in the simple animal host Caenorhabditis elegans. Secondary metabolites phenazine-1-carboxamide and pyochelin activate a G protein-signaling pathway in the ASJ chemosensory neuron pair that induces expression of the neuromodulator DAF-7/TGF-β. DAF-7, in turn, activates a canonical TGF-β signaling pathway in adjacent interneurons to modulate aerotaxis behavior and promote avoidance of pathogenic P. aeruginosa. Our data provide a chemical, genetic, and neuronal basis for how the behavior and physiology of a simple animal host can be modified by the microbial environment, and suggest that secondary metabolites produced by microbes may provide environmental cues that contribute to pathogen recognition and host survival. PMID:25303524

  7. Secondary metabolites from Tetracera potatoria stem bark with anti-mycobacterial activity.

    PubMed

    Fomogne-Fodjo, M C Y; Ndinteh, D T; Olivier, D K; Kempgens, P; van Vuuren, S; Krause, R W M

    2017-01-04

    Tetracera potatoria Afzel. Exg. Don (Dilleniaceae) is a medicinal plant used traditionally in Africa for the treatment of tuberculosis related ailments and respiratory infections. The antibacterial activity of the medium polar extracts of T. potatoria leaves and stem bark was recently reported against Mycobacterium smegmatis (MIC 25µg/mL) and M. aurum (65µg/mL), two fast-growing Mycobacterium strains used as model micro-organisms for the more pathogenic strain Mycobacterium tuberculosis (Fomogne-Fodjo et al., 2014). The aim of this study was consequently to isolate the compounds possibly contributing to this activity, and which may therefore be promising precursors to be used for the development of novel anti-TB drugs. T. potatoria medium polar extract [MeOH/DCM (1:1, v/v)] was fractionated sequentially with petroleum ether to which EtOAC and MeOH were gradually added to increase the polarity. The examination of T. potatoria extract and its fractions was guided by bioassays for anti-mycobacterial activity against M. smegmatis (ATCC 23246) and M. aurum (NCTC 10437) using the minimum inhibitory concentration (MIC) method. All the isolated compounds were structurally elucidated using spectroscopic techniques and evaluated for their anti-mycobacterial activity. Two novel secondary metabolites (1, 2) named tetraceranoate and N-hydroxy imidate-tetracerane, together with five known compounds [β-stigmasterol (3), stigmast-5-en-3β-yl acetate (4), betulinic acid (5), betulin (6) and lupeol (7)] were isolated and identified. Tetraceranoate exhibited the best activity against M. smegmatis with a minimum inhibitory concentration (MIC) of 7.8µg/mL, while β-stigmasterol, betulinic acid and betulin showed appreciable anti-mycobacterial activity against both strains (MIC 15µg/mL). Seven compounds were isolated from the medium polar extract [MeOH/DCM (1:1, v/v)] of T. potatoria stem bark. Only tetraceranoate one of the isolated compounds showed antibacterial activity against

  8. A novel fungal metabolite with beneficial properties for agricultural applications.

    PubMed

    Vinale, Francesco; Manganiello, Gelsomina; Nigro, Marco; Mazzei, Pierluigi; Piccolo, Alessandro; Pascale, Alberto; Ruocco, Michelina; Marra, Roberta; Lombardi, Nadia; Lanzuise, Stefania; Varlese, Rosaria; Cavallo, Pierpaolo; Lorito, Matteo; Woo, Sheridan L

    2014-07-08

    Trichoderma are ubiquitous soil fungi that include species widely used as biocontrol agents in agriculture. Many isolates are known to secrete several secondary metabolites with different biological activities towards plants and other microbes. Harzianic acid (HA) is a T. harzianum metabolite able to promote plant growth and strongly bind iron. In this work, we isolated from the culture filtrate of a T. harzianum strain a new metabolite, named isoharzianic acid (iso-HA), a stereoisomer of HA. The structure and absolute configuration of this compound has been determined by spectroscopic methods, including UV-Vis, MS, 1D and 2D NMR analyses. In vitro applications of iso-HA inhibited the mycelium radial growth of Sclerotinia sclerotiorum and Rhizoctonia solani. Moreover, iso HA improved the germination of tomato seeds and induced disease resistance. HPLC-DAD experiments showed that the production of HA and iso HA was affected by the presence of plant tissue in the liquid medium. In particular, tomato tissue elicited the production of HA but negatively modulated the biosynthesis of its analogue iso-HA, suggesting that different forms of the same Trichoderma secondary metabolite have specific roles in the molecular mechanism regulating the Trichoderma plant interaction.

  9. Effect of tibolone and its principal metabolites (3α- and 3β-hydroxy, 3α-sulfate, and 4-ene derivatives) on estrone sulfatase activity in normal and cancerous human breast tissue.

    PubMed

    Chetrite, Gérard S; Cortes-Prieto, Joaquin; Pasqualini, Jorge R

    2011-12-01

    Tibolone (Org-OD14) is the active substance of Livial®, a synthetic steroid with the structure 7α,17α-17-hydroxy-7-methyl-19-norpregn-5(10)-en-20-yn-3-one, possessing weak tissue-specific estrogenic, progestogenic, and androgenic properties, used to treat menopausal complaints. After oral administration, tibolone is extensively metabolized into the 3α-(Org-4904) and 3β-(Org-30126) hydroxy derivatives with estrogenic properties, its 4-ene (Org-OM38) isomer with progestogenic/androgenic activities, and the 3α-sulfate (Org-34322) derivative, a major biologically inactive circulating form. We compared the dose response of tibolone and its metabolites on estrone sulfatase activity [conversion of estrone sulfate (E1S) to estrone (E1)] in normal and cancerous human breast tissues. Tissue minces were incubated with physiological concentrations of [3H]-E1S (5×10-9M) alone or in the presence of tibolone and its metabolites (concentration range: 5×10-7to 5×10-5M) for 4 h. Tritiated E1, estradiol (E2), and E1S were separated and evaluated quantitatively by thin-layer chromatography. The sulfatase activity was significantly higher in cancerous breast but strongly inhibited by tibolone and the different metabolites, whereas 3α- and 3β-hydroxy derivatives were the most potent inhibitors. This very significant inhibitory effect of tibolone and its principal metabolites on the enzyme involved in E2biosynthesis in the human breast provides interesting perspectives to study the biological responses of these compounds in trials with breast cancer patients.

  10. Anticancer effect and structure-activity analysis of marine products isolated from metabolites of mangrove fungi in the South China Sea.

    PubMed

    Tao, Li-yang; Zhang, Jian-ye; Liang, Yong-ju; Chen, Li-ming; Zhen, Li-sheng; Wang, Fang; Mi, Yan-jun; She, Zhi-gang; To, Kenneth Kin Wah; Lin, Yong-cheng; Fu, Li-wu

    2010-04-01

    Marine-derived fungi provide plenty of structurally unique and biologically active secondary metabolites. We screened 87 marine products from mangrove fungi in the South China Sea for anticancer activity by MTT assay. 14% of the compounds (11/86) exhibited a potent activity against cancer in vitro. Importantly, some compounds such as compounds 78 and 81 appeared to be promising for treating cancer patients with multidrug resistance, which should encourage more efforts to isolate promising candidates for further development as clinically useful chemotherapeutic drugs. Furthermore, DNA intercalation was not involved in their anticancer activities, as determined by DNA binding assay. On the other hand, the structure-activity analysis indicated that the hydroxyl group was important for their cytotoxic activity and that bulky functional groups such as phenyl rings could result in a loss of biological activity, which will direct the further development of marine product-based derivatives.

  11. High-Fat Diet and Voluntary Chronic Aerobic Exercise Recover Altered Levels of Aging-Related Tryptophan Metabolites along the Kynurenine Pathway

    PubMed Central

    Lee, Keon-Joo; Cho, Joo-Youn; Lee, Soon-Tae; Kim, Hwa Suk; Shim, Jun Hwa; Lee, Sang Kun; Kim, Manho

    2017-01-01

    Tryptophan metabolites regulate a variety of physiological processes, and their downstream metabolites enter the kynurenine pathway. Age-related changes of metabolites and activities of associated enzymes in this pathway are suggestable and would be potential intervention targets. Blood levels of serum tryptophan metabolites in C57BL/6 mice of different ages, ranging from 6 weeks to 10 months, were assessed using high-performance liquid chromatography, and the enzyme activities for each metabolic step were estimated using the ratio of appropriate metabolite levels. Mice were subjected to voluntary chronic aerobic exercise or high-fat diet to assess their ability to rescue age-related alterations in the kynurenine pathway. The ratio of serum kynurenic acid (KYNA) to 3-hydroxylkynurenine (3-HK) decreased with advancing age. Voluntary chronic aerobic exercise and high-fat diet rescued the decreased KYNA/3-HK ratio in the 6-month-old and 8-month-old mice groups. Tryptophan metabolites and their associated enzyme activities were significantly altered during aging, and the KYNA/3-HK ratio was a meaningful indicator of aging. Exercise and high-fat diet could potentially recover the reduction of the KYNA/3-HK ratio in the elderly. PMID:28680298

  12. Functional metabolite assemblies—a review

    NASA Astrophysics Data System (ADS)

    Aizen, Ruth; Tao, Kai; Rencus-Lazar, Sigal; Gazit, Ehud

    2018-05-01

    Metabolites are essential for the normal operation of cells and fulfill various physiological functions. It was recently found that in several metabolic disorders, the associated metabolites could self-assemble to generate amyloid-like structures, similar to canonical protein amyloids that have a role in neurodegenerative disorders. Yet, assemblies with typical amyloid characteristics are also known to have physiological function. In addition, many non-natural proteins and peptides presenting amyloidal properties have been used for the fabrication of functional nanomaterials. Similarly, functional metabolite assemblies are also found in nature, demonstrating various physiological roles. A notable example is the structural color formed by guanine crystals or fluorescent crystals in feline eyes responsible for enhanced night vision. Moreover, some metabolites have been used for the in vitro fabrication of functional materials, such as glycine crystals presenting remarkable piezoelectric properties or indigo films used to assemble organic semi-conductive electronic devices. Therefore, we believe that the study of metabolite assemblies is not only important in order to understand their role in normal physiology and in pathology, but also paves a new route in exploring the fabrication of organic, bio-compatible materials.

  13. Secondary metabolites from the unique bamboo, Melocanna baccifera.

    PubMed

    Govindan, Balaji; Johnson, Anil John; Viswanathan, Gayathri; Ramaswamy, Venkataraman; Koshy, Konnath Chacko; Baby, Sabulal

    2018-02-15

    Phytochemistry of fruits and leaves of the unique bamboo Melocanna baccifera resulted in the isolation of 27 secondary metabolites, including 4-Oxabicyclo[3.2.2]nona-1(7),5,8-triene and Verbacine. Biological activity studies of Verbacine revealed it as an inhibitor of acetylcholinesterase and as cytotoxic against C6 cancer cells.

  14. [Microbial secondary metabolites as potential reserve of pharmaceuticals].

    PubMed

    Orlova, T I; Bulgakova, V G; Polin, A N

    2014-01-01

    The major characteristics of new bioactive microbial secondary metabolites are summarized in the review. A wide range of new molecular targets are implicated in discovery of new nonantibiotic compounds with some other pharmacological activities (noninfectious diseases). Microorganisms represent fascinating resources due to their production of novel products with broad spectra of bioactivities.

  15. Pharmacokinetics, Tissue Distribution, and Anti-Lipogenic/Adipogenic Effects of Allyl-Isothiocyanate Metabolites

    PubMed Central

    Ahn, Jiyun; Chung, Woo-Jae; Jang, Young Jin; Seong, Ki-Seung; Moon, Jae-Hak; Ha, Tae Youl; Jung, Chang Hwa

    2015-01-01

    Allyl-isothiocyanate (AITC) is an organosulfur phytochemical found in abundance in common cruciferous vegetables such as mustard, wasabi, and cabbage. Although AITC is metabolized primarily through the mercapturic acid pathway, its exact pharmacokinetics remains undefined and the biological function of AITC metabolites is still largely unknown. In this study, we evaluated the inhibitory effects of AITC metabolites on lipid accumulation in vitro and elucidated the pharmacokinetics and tissue distribution of AITC metabolites in rats. We found that AITC metabolites generally conjugate with glutathione (GSH) or N-acetylcysteine (NAC) and are distributed in most organs and tissues. Pharmacokinetic analysis showed a rapid uptake and complete metabolism of AITC following oral administration to rats. Although AITC has been reported to exhibit anti-tumor activity in bladder cancer, the potential bioactivity of its metabolites has not been explored. We found that GSH-AITC and NAC-AITC effectively inhibit adipogenic differentiation of 3T3-L1 preadipocytes and suppress expression of PPAR-γ, C/EBPα, and FAS, which are up-regulated during adipogenesis. GSH-AITC and NAC-AITC also suppressed oleic acid-induced lipid accumulation and lipogenesis in hepatocytes. Our findings suggest that AITC is almost completely metabolized in the liver and rapidly excreted in urine through the mercapturic acid pathway following administration in rats. AITC metabolites may exert anti-obesity effects through suppression of adipogenesis or lipogenesis. PMID:26317351

  16. Pharmacokinetics, Tissue Distribution, and Anti-Lipogenic/Adipogenic Effects of Allyl-Isothiocyanate Metabolites.

    PubMed

    Kim, Yang-Ji; Lee, Da-Hye; Ahn, Jiyun; Chung, Woo-Jae; Jang, Young Jin; Seong, Ki-Seung; Moon, Jae-Hak; Ha, Tae Youl; Jung, Chang Hwa

    2015-01-01

    Allyl-isothiocyanate (AITC) is an organosulfur phytochemical found in abundance in common cruciferous vegetables such as mustard, wasabi, and cabbage. Although AITC is metabolized primarily through the mercapturic acid pathway, its exact pharmacokinetics remains undefined and the biological function of AITC metabolites is still largely unknown. In this study, we evaluated the inhibitory effects of AITC metabolites on lipid accumulation in vitro and elucidated the pharmacokinetics and tissue distribution of AITC metabolites in rats. We found that AITC metabolites generally conjugate with glutathione (GSH) or N-acetylcysteine (NAC) and are distributed in most organs and tissues. Pharmacokinetic analysis showed a rapid uptake and complete metabolism of AITC following oral administration to rats. Although AITC has been reported to exhibit anti-tumor activity in bladder cancer, the potential bioactivity of its metabolites has not been explored. We found that GSH-AITC and NAC-AITC effectively inhibit adipogenic differentiation of 3T3-L1 preadipocytes and suppress expression of PPAR-γ, C/EBPα, and FAS, which are up-regulated during adipogenesis. GSH-AITC and NAC-AITC also suppressed oleic acid-induced lipid accumulation and lipogenesis in hepatocytes. Our findings suggest that AITC is almost completely metabolized in the liver and rapidly excreted in urine through the mercapturic acid pathway following administration in rats. AITC metabolites may exert anti-obesity effects through suppression of adipogenesis or lipogenesis.

  17. Isolated and mixed effects of diuron and its metabolites on biotransformation enzymes and oxidative stress response of Nile tilapia (Oreochromis niloticus).

    PubMed

    Felício, Andréia Arantes; Freitas, Juliane Silberschmidt; Scarin, Jéssica Bolpeti; de Souza Ondei, Luciana; Teresa, Fabrício Barreto; Schlenk, Daniel; de Almeida, Eduardo Alves

    2018-03-01

    Diuron is one of the most used herbicide in the world, and its field application has been particularly increased in Brazil due to the expansion of sugarcane crops. Diuron has often been detected in freshwater ecosystems and it can be biodegraded into three main metabolites in the environment, the 3,4-dichloroaniline (DCA), 3,4-dichlorophenylurea (DCPU) and 3,4-dichlorophenyl-N-methylurea (DCPMU). Negative effects under aquatic biota are still not well established for diuron, especially when considering its presence in mixture with its different metabolites. In this study, we evaluated the effects of diuron alone or in combination with its metabolites, DCPMU, DCPU and 3,4-DCA on biochemical stress responses and biotransformation activity of the fish Oreochromis niloticus. Results showed that diuron and its metabolites caused significant but dispersed alterations in oxidative stress markers and biotransformation enzymes, except for ethoxyresorufin-O-deethylase (EROD) activity, that presented a dose-dependent increase after exposure to either diuron or its metabolites. Glutathione S-transferase (GST) activity was significant lower in gills after exposure to diuron metabolites, but not diuron. Diuron, DCPMU and DCA also decreased the multixenobiotic resistance (MXR) activity. Lipid peroxidation levels were increased in gill after exposure to all compounds, indicating that the original compound and diuron metabolites can induce oxidative stress in fish. The integration of all biochemical responses by the Integrated Biomarker Response (IBR) model indicated that all compounds caused significant alterations in O. niloticus, but DCPMU caused the higher alterations in both liver and gill. Our findings imply that diuron and its metabolites may impair the physiological response related to biotransformation and antioxidant activity in fish at field concentrations. Such alterations could interfere with the ability of aquatic animals to adapt to environments contaminated by

  18. Two new metabolites from a soil fungus Curvularia affinis strain HS-FG-196.

    PubMed

    Zhang, Hui; Mao, Liang-Liang; Qian, Ping-Ting; Shan, Wei-Guang; Wang, Ji-Dong; Bai, Hua

    2012-01-01

    Two new metabolites, pyrenocine J (1) and pyrenochaetic acid D (2), together with two known metabolites, pyrenocine A (3) and pyrenochaetic acid A (4), were isolated from a soil fungus, Curvularia affinis strain HS-FG-196. Their structures were established by extensive spectroscopic analysis. Compound 1 showed cytotoxic activity against the human hepatic cancer cell line HepG2 with an IC(50) value of 28.5 μg/ml.

  19. [Inhibition of the lymphocyte response by metabolites released by the lipoxygenase of mouse macrophages].

    PubMed

    Gualde, N; Rigaud, M; Rabinovitch, H; Durand, J; Beneytout, J L; Breton, J C

    1981-10-26

    Arachidonic acid can be transformed into a series of metabolites by the lipoxygenase enzyme activity of Mouse peritoneal macrophages. The resulting metabolites inhibit tritiated thymidine uptake by Mouse splenocytes stimulated by ConA or PHA. They suppress the development of killer cells. When mice are injected with 15-hydroperoxide, their splenocytes show a decreased H3-thymidine uptake after lectin stimulation.

  20. Ecological Roles and Biological Activities of Specialized Metabolites from the Genus Nicotiana.

    PubMed

    Jassbi, Amir Reza; Zare, Somayeh; Asadollahi, Mojtaba; Schuman, Meredith C

    2017-10-11

    Species of Nicotiana grow naturally in different parts of the world and have long been used both medicinally and recreationally by human societies. More recently in our history, Nicotiana tabacum has attracted interest as one of the most economically important industrial crops. Nicotiana species are frequently investigated for their bioactive natural products, and the ecological role of their specialized metabolites in responses to abiotic stress or biotic stress factors like pathogens and herbivores. The interest of tobacco companies in genetic information as well as the success of a few wild tobacco species as experimental model organisms have resulted in growing knowledge about the molecular biology and ecology of these plants and functional studies of the plant's natural products. Although a large number of reviews and books on biologically active natural products already exists, mostly from N. tabacum, we focus our attention on the ecological roles and biological activity of natural products, versus products from cured and processed material, in this Review. The studied compounds include alkaloids, aromatic compounds, flavonoids, volatiles, sesquiterpenoids, diterpenes alcohols, and sugar esters from trichomes of the plants, and recently characterized acyclic hydroxygeranyllinalool diterpene glycosides (HGL-DTGs). In this Review (1800s-2017), we describe the above-mentioned classes of natural products, emphasizing their biological activities and functions as they have been determined either in bioassay-guided purification approaches or in bioassays with plants in which the expression of specific biosynthetic genes has been genetically manipulated. Additionally, a review on the history, taxonomy, ecology, and medicinal application of different Nicotiana species growing around the globe presented in this Review may be of interest for pharmacognosists, natural products, and ecological chemists.

  1. A simulation study on the constancy of cardiac energy metabolites during workload transition.

    PubMed

    Saito, Ryuta; Takeuchi, Ayako; Himeno, Yukiko; Inagaki, Nobuya; Matsuoka, Satoshi

    2016-12-01

    The cardiac energy metabolites such as ATP, phosphocreatine, ADP and NADH are kept relatively constant during physiological cardiac workload transition. How this is accomplished is not yet clarified, though Ca 2+ has been suggested to be one of the possible mechanisms. We constructed a detailed mathematical model of cardiac mitochondria based on experimental data and studied whether known Ca 2+ -dependent regulation mechanisms play roles in the metabolite constancy. Model simulations revealed that the Ca 2+ -dependent regulation mechanisms have important roles under the in vitro condition of isolated mitochondria where malate and glutamate were mitochondrial substrates, while they have only a minor role and the composition of substrates has marked influence on the metabolite constancy during workload transition under the simulated in vivo condition where many substrates exist. These results help us understand the regulation mechanisms of cardiac energy metabolism during physiological cardiac workload transition. The cardiac energy metabolites such as ATP, phosphocreatine, ADP and NADH are kept relatively constant over a wide range of cardiac workload, though the mechanisms are not yet clarified. One possible regulator of mitochondrial metabolism is Ca 2+ , because it activates several mitochondrial enzymes and transporters. Here we constructed a mathematical model of cardiac mitochondria, including oxidative phosphorylation, substrate metabolism and ion/substrate transporters, based on experimental data, and studied whether the Ca 2+ -dependent activation mechanisms play roles in metabolite constancy. Under the in vitro condition of isolated mitochondria, where malate and glutamate were used as mitochondrial substrates, the model well reproduced the Ca 2+ and inorganic phosphate (P i ) dependences of oxygen consumption, NADH level and mitochondrial membrane potential. The Ca 2+ -dependent activations of the aspartate/glutamate carrier and the F 1 F o -ATPase, and

  2. [Influence of diethyl sulfate (DES) mutagenesis on growth properties and pigment secondary metabolites of Phellinus igniarius].

    PubMed

    Wang, Jing; Wu, Xin-yuan; Ma, Wei; Chen, Jing; Liu, Cheng; Wu, Xiu-li

    2015-06-01

    The diethyl sulfate (DES) mutagenesis was chosen for the mutagenic treatment to Phellinus igniarius, and the relationship of mutagenesis time and death rate was investigated with 0.5% DES. The differences of mycelial growth speed, liquid fermentation mycelia biomass, morphology and pigment classes of secondary metabolites production speed and antioxidant activities of metabolite products were discussed. The study displayed that DES mutagenesis could change mycelial morphology without obvious effect on mycelium growth, and the DES mutagenesis improved antioxidant activities of the active ingredients of P. igniarius and had more antioxidant activity of hypoxia/sugar PC12 nerve cells than that of P. igniarius.

  3. Visualizing fungal metabolites during mycoparasitic interaction by MALDI mass spectrometry imaging

    PubMed Central

    Holzlechner, Matthias; Reitschmidt, Sonja; Gruber, Sabine; Zeilinger, Susanne

    2016-01-01

    Studying microbial interactions by MALDI mass spectrometry imaging (MSI) directly from growing media is a difficult task if high sensitivity is demanded. We present a quick and robust sample preparation strategy for growing fungi (Trichoderma atroviride, Rhizoctonia solani) on glass slides to establish a miniaturized confrontation assay. By this we were able to visualize metabolite distributions by MALDI MSI after matrix deposition with a home‐built sublimation device and thorough recrystallization. We present for the first time MALDI MSI data for secondary metabolite release during active mycoparasitism. PMID:26959280

  4. Irreversible Inhibition of EGFR: Modeling the Combined Pharmacokinetic-Pharmacodynamic Relationship of Osimertinib and Its Active Metabolite AZ5104.

    PubMed

    Yates, James W T; Ashton, Susan; Cross, Darren; Mellor, Martine J; Powell, Steve J; Ballard, Peter

    2016-10-01

    Osimertinib (AZD9291) is a potent, selective, irreversible inhibitor of EGFR-sensitizing (exon 19 and L858R) and T790M-resistant mutation. In vivo, in the mouse, it is metabolized to an active des-methyl metabolite, AZ5104. To understand the therapeutic potential in patients, this study aimed to assess the relationship between osimertinib pharmacokinetics, the pharmacokinetics of the active metabolite, the pharmacodynamics of phosphorylated EGFR reduction, and efficacy in mouse xenograft models of EGFR-driven cancers, including two NSCLC lines. Osimertinib was dosed in xenografted models of EGFR-driven cancers. In one set of experiments, changes in phosphorylated EGFR were measured to confirm target engagement. In a second set of efficacy studies, the resulting changes in tumor volume over time after repeat dosing of osimertinib were observed. To account for the contributions of both molecules, a mathematical modeling approach was taken to integrate the resulting datasets. The model was able to describe the pharmacokinetics, pharmacodynamics, and efficacy in A431, PC9, and NCI-H1975 xenografts, with the differences in sensitivity described by the varying potency against wild-type, sensitizing, and T790M-mutant EGFR and the phosphorylated EGFR reduction required to reduce tumor volume. It was inferred that recovery of pEGFR is slower after chronic dosing due to reduced resynthesis. It was predicted and further demonstrated that although inhibition is irreversible, the resynthesis of EGFR is such that infrequent intermittent dosing is not as efficacious as once daily dosing. Mol Cancer Ther; 15(10); 2378-87. ©2016 AACR. ©2016 American Association for Cancer Research.

  5. Evaluation of the pharmacokinetics of oral amitriptyline and its active metabolite nortriptyline in fed and fasted Greyhound dogs.

    PubMed

    Norkus, C; Rankin, D; KuKanich, B

    2015-12-01

    This study reports the pharmacokinetics of oral amitriptyline and its active metabolite nortriptyline in Greyhound dogs. Five healthy Greyhound dogs were enrolled in a randomized crossover design. A single oral dose of amitriptyline hydrochloride (actual mean dose 8.1 per kg) was administered to fasted or fed dogs. Blood samples were collected at predetermined times from 0 to 24 h after administration, and plasma drug concentrations were measured by liquid chromatography with mass spectrometry. Noncompartmental pharmacokinetic analyses were performed. Two dogs in the fasted group vomited following amitriptyline administration and were excluded from analysis. The range of amitriptyline CMAX for the remaining fasted dogs (n = 3) was 22.8-64.5 ng/mL compared to 30.6-127 ng/mL for the fed dogs (n = 5). The range of the amitriptyline AUCINF for the three fasted dogs was 167-720 h·ng/mL compared to 287-1146 h·ng/mL for fed dogs. The relative bioavailability of amitriptyline in fasted dogs compared to fed dogs was 69-91% (n = 3). The exposure of the active metabolite nortriptyline was correlated to amitriptyline exposure (R(2)  = 0.84). Due to pharmacokinetic variability and the small number of dogs completing this study, further studies are needed assessing the impact of feeding on oral amitriptyline pharmacokinetics. Amitriptyline may be more likely to cause vomiting in fasted dogs. © 2015 John Wiley & Sons Ltd.

  6. Seasonal behavior of Thalassia testudinum (Hydrocharitaceae) metabolites.

    PubMed

    Hernández, Yasnay; González, Kethia; Valdés-Iglesias, Olga; Zarabozo, Akaena; Portal, Yéssica; Laguna, Abilio; Martínez-Daranas, Beatriz; Rodríguez, Maria; Gutiérrez, Richard

    2016-12-01

    The marine angiosperm Thalassia testudinum, commonly known as turtle grass, is a dominant seagrass that grows in the Caribbean Sea shelf associated to Syringodium filiforme. The hydroalcoholic extract of T. testudinum is rich in polyphenols; the most abundant metabolite in this extract is thalassiolin B, a glycosilated flavonoid with skin damage repairing properties, and antioxidant capacity among others. The present study aimed at generating information about the seasonal behavior of secondary metabolites, as well as to study the antioxidant capacity of the T. testudinum leaves extract, collected monthly during 2012 from the Northeast coastline of Havana, Cuba. For this study, spectrophotometric methods were used to determine the concentrations of polyphenols, flavonoids, anthocyanins, soluble carbohydrates and proteins, chlorophylls a and b, and antioxidant activity of the extracts. In general, results demonstrated seasonal variations of the analyzed parameters. Extracts prepared from the vegetal material collected in October and November showed the highest values of polyphenols (58.81 ± 1.53 and 52.39 ± 0.63 mg/g bs, respectivally) and flavonoids (44.12 ± 1.30 and 51.30 ± 0.67 mg/gdw, respectively). On the contrary, the lowest values of polyphenols were found in extracts of leaves collected in July and August (15.51 ± 0.84 and 13.86 ± 0.48 mg/g,respectively). In accordance with these results, the lower value of Inhibitory Concentration (IC50) was obtained to get a 50 % of maximal effect on free radical scavenging activity with the extracts prepared from leaves collected in October and November, and less significant IC50 was obtained from the extract prepared from leaves collected in August (5.63 mg/mL). A negative correlation (r= -0.694) was observed in this study between the content of polyphenols and the IC50 necessary to get the half of its antioxidant maximal effect. The high correspondence between the maximum values of polyphenols, flavonoids

  7. Insular Cortex Metabolite Changes in Obstructive Sleep Apnea

    PubMed Central

    Yadav, Santosh K.; Kumar, Rajesh; Macey, Paul M.; Woo, Mary A.; Yan-Go, Frisca L.; Harper, Ronald M.

    2014-01-01

    Study Objective: Adults with obstructive sleep apnea (OSA) show significant autonomic and neuropsychologic deficits, which may derive from damage to insular regions that serve those functions. The aim was to assess glial and neuronal status from anterior insular metabolites in OSA versus controls, using proton magnetic resonance spectroscopy (PMRS), and thus to provide insights for neuroprotection against tissue changes, and to reduce injury consequences. Design: Cross-sectional study. Setting: University-based medical center. Participants: Thirty-six patients with OSA, 53 controls. Interventions: None. Measurements and Results: We performed PMRS in bilateral anterior insulae using a 3.0-Tesla magnetic resonance imaging scanner, calculated N-acetylaspartate/creatine (NAA/Cr), choline/creatine (Cho/Cr), myo-inositol/creatine (MI/Cr), and MI/NAA metabolite ratios, and examined daytime sleepiness (Epworth Sleepiness Scale, ESS), sleep quality (Pittsburgh Sleep Quality Index, PSQI), and neuropsychologic status (Beck Depression Inventory II [BDI-II] and Beck Anxiety Inventory [BAI]). Body mass index, BAI, BDI-II, PSQI, and ESS significantly differed between groups. NAA/ Cr ratios were significantly reduced bilaterally, and left-sided MI/Cr and MI/NAA ratios were increased in OSA over controls. Significant positive correlations emerged between left insular MI/Cr ratios and apnea-hypopnea index values, right insular Cho/Cr ratios and BDI-II and BAI scores, and negative correlations appeared between left insular NAA/Cr ratios and PSQI scores and between right-side MI/Cr ratios and baseline and nadir change in O2 saturation. Conclusions: Adults with obstructive sleep apnea showed bilaterally reduced N-acetylaspartate and left-side increased myo-inositol anterior insular metabolites, indicating neuronal damage and increased glial activation, respectively, which may contribute to abnormal autonomic and neuropsychologic functions in the condition. The activated glial status

  8. Use of High-Pressure Liquid Chromatography to Determine Plasma Levels of Metronidazole and Metabolites After Intravenous Administration

    PubMed Central

    Wheeler, L. A.; De Meo, M.; Halula, M.; George, L.; Heseltine, P.

    1978-01-01

    A rapid and sensitive high-pressure liquid chromatography assay for metronidazole and its two principle metabolites, 1-(2-hydroxyethyl-2-hydroxymethyl)-5-nitro-imidazole [hydroxy metabolite] and 1-acetic acid-2-methyl-5-metronidazole [acid metabolite], was developed. The retention times observed were 5.7, 3.3, and 4.5 min, respectively. A reverse-phase μC18 Bondapak column using a solvent system of methanol, acetonitrile, and 0.005 M pH 4 potassium dihydrogen phosphate (4:3:93, vol/vol) was used to achieve separation of the three compounds. Patients receiving metronidazole therapy were given a loading dose of 13.6 mg of drug per kg intravenously over 1 h, followed by a maintenance dose of 1.43 mg/kg per h. The range of metronidazole concentrations observed was 6.8 to 47.5 μg/ml. These levels are well above the minimal inhibitory concentrations of most clinically significant anaerobic bacteria including Bacteroides fragilis. Little of the acid metabolite was observed in the plasma. The concentration of hydroxy metabolite ranged from 1.6 to 16 μg/ml. The latter may represent an additional source of antimicrobial activity since the hydroxy metabolite has approximately 30% the biological activity of metronidazole. PMID:646342

  9. Secondary metabolites in fungus-plant interactions

    PubMed Central

    Pusztahelyi, Tünde; Holb, Imre J.; Pócsi, István

    2015-01-01

    Fungi and plants are rich sources of thousands of secondary metabolites. The genetically coded possibilities for secondary metabolite production, the stimuli of the production, and the special phytotoxins basically determine the microscopic fungi-host plant interactions and the pathogenic lifestyle of fungi. The review introduces plant secondary metabolites usually with antifungal effect as well as the importance of signaling molecules in induced systemic resistance and systemic acquired resistance processes. The review also concerns the mimicking of plant effector molecules like auxins, gibberellins and abscisic acid by fungal secondary metabolites that modulate plant growth or even can subvert the plant defense responses such as programmed cell death to gain nutrients for fungal growth and colonization. It also looks through the special secondary metabolite production and host selective toxins of some significant fungal pathogens and the plant response in form of phytoalexin production. New results coming from genome and transcriptional analyses in context of selected fungal pathogens and their hosts are also discussed. PMID:26300892

  10. Secondary Metabolites Produced during the Germination of Streptomyces coelicolor.

    PubMed

    Čihák, Matouš; Kameník, Zdeněk; Šmídová, Klára; Bergman, Natalie; Benada, Oldřich; Kofroňová, Olga; Petříčková, Kateřina; Bobek, Jan

    2017-01-01

    Spore awakening is a series of actions that starts with purely physical processes and continues via the launching of gene expression and metabolic activities, eventually achieving a vegetative phase of growth. In spore-forming microorganisms, the germination process is controlled by intra- and inter-species communication. However, in the Streptomyces clade, which is capable of developing a plethora of valuable compounds, the chemical signals produced during germination have not been systematically studied before. Our previously published data revealed that several secondary metabolite biosynthetic genes are expressed during germination. Therefore, we focus here on the secondary metabolite production during this developmental stage. Using high-performance liquid chromatography-mass spectrometry, we found that the sesquiterpenoid antibiotic albaflavenone, the polyketide germicidin A, and chalcone are produced during germination of the model streptomycete, S. coelicolor . Interestingly, the last two compounds revealed an inhibitory effect on the germination process. The secondary metabolites originating from the early stage of microbial growth may coordinate the development of the producer ( quorum sensing ) and/or play a role in competitive microflora repression ( quorum quenching ) in their nature environments.

  11. Secondary Metabolites Produced during the Germination of Streptomyces coelicolor

    PubMed Central

    Čihák, Matouš; Kameník, Zdeněk; Šmídová, Klára; Bergman, Natalie; Benada, Oldřich; Kofroňová, Olga; Petříčková, Kateřina; Bobek, Jan

    2017-01-01

    Spore awakening is a series of actions that starts with purely physical processes and continues via the launching of gene expression and metabolic activities, eventually achieving a vegetative phase of growth. In spore-forming microorganisms, the germination process is controlled by intra- and inter-species communication. However, in the Streptomyces clade, which is capable of developing a plethora of valuable compounds, the chemical signals produced during germination have not been systematically studied before. Our previously published data revealed that several secondary metabolite biosynthetic genes are expressed during germination. Therefore, we focus here on the secondary metabolite production during this developmental stage. Using high-performance liquid chromatography-mass spectrometry, we found that the sesquiterpenoid antibiotic albaflavenone, the polyketide germicidin A, and chalcone are produced during germination of the model streptomycete, S. coelicolor. Interestingly, the last two compounds revealed an inhibitory effect on the germination process. The secondary metabolites originating from the early stage of microbial growth may coordinate the development of the producer (quorum sensing) and/or play a role in competitive microflora repression (quorum quenching) in their nature environments. PMID:29326665

  12. Biodegradation of clofibric acid and identification of its metabolites.

    PubMed

    Salgado, R; Oehmen, A; Carvalho, G; Noronha, J P; Reis, M A M

    2012-11-30

    Clofibric acid (CLF) is the pharmaceutically active metabolite of lipid regulators clofibrate, etofibrate and etofyllinclofibrate, and it is considered both environmentally persistent and refractory. This work studied the biotransformation of CLF in aerobic sequencing batch reactors (SBRs) with mixed microbial cultures, monitoring the efficiency of biotransformation of CLF and the production of metabolites. The maximum removal achieved was 51% biodegradation (initial CLF concentration=2 mg L(-1)), where adsorption and abiotic removal mechanisms were shown to be negligible, showing that CLF is indeed biodegradable. Tests showed that the observed CLF biodegradation was mainly carried out by heterotrophic bacteria. Three main metabolites were identified, including α-hydroxyisobutyric acid, lactic acid and 4-chlorophenol. The latter is known to exhibit higher toxicity than the parent compound, but it did not accumulate in the SBRs. α-Hydroxyisobutyric acid and lactic acid accumulated for a period, where nitrite accumulation may have been responsible for inhibiting their degradation. A metabolic pathway for the biodegradation of CLF is proposed in this study. Copyright © 2012 Elsevier B.V. All rights reserved.

  13. Metabolite damage and repair in metabolic engineering design.

    PubMed

    Sun, Jiayi; Jeffryes, James G; Henry, Christopher S; Bruner, Steven D; Hanson, Andrew D

    2017-11-01

    The necessarily sharp focus of metabolic engineering and metabolic synthetic biology on pathways and their fluxes has tended to divert attention from the damaging enzymatic and chemical side-reactions that pathway metabolites can undergo. Although historically overlooked and underappreciated, such metabolite damage reactions are now known to occur throughout metabolism and to generate (formerly enigmatic) peaks detected in metabolomics datasets. It is also now known that metabolite damage is often countered by dedicated repair enzymes that undo or prevent it. Metabolite damage and repair are highly relevant to engineered pathway design: metabolite damage reactions can reduce flux rates and product yields, and repair enzymes can provide robust, host-independent solutions. Herein, after introducing the core principles of metabolite damage and repair, we use case histories to document how damage and repair processes affect efficient operation of engineered pathways - particularly those that are heterologous, non-natural, or cell-free. We then review how metabolite damage reactions can be predicted, how repair reactions can be prospected, and how metabolite damage and repair can be built into genome-scale metabolic models. Lastly, we propose a versatile 'plug and play' set of well-characterized metabolite repair enzymes to solve metabolite damage problems known or likely to occur in metabolic engineering and synthetic biology projects. Copyright © 2017 International Metabolic Engineering Society. All rights reserved.

  14. Metabolite damage and repair in metabolic engineering design

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

    Sun, Jiayi; Jeffryes, James G.; Henry, Christopher S.

    The necessarily sharp focus of metabolic engineering and metabolic synthetic biology on pathways and their fluxes has tended to divert attention from the damaging enzymatic and chemical side-reactions that pathway metabolites can undergo. Although historically overlooked and underappreciated, such metabolite damage reactions are now known to occur throughout metabolism and to generate (formerly enigmatic) peaks detected in metabolomics datasets. It is also now known that metabolite damage is often countered by dedicated repair enzymes that undo or prevent it. Metabolite damage and repair are highly relevant to engineered pathway design: metabolite damage reactions can reduce flux rates and product yields,more » and repair enzymes can provide robust, host-independent solutions. Herein, after introducing the core principles of metabolite damage and repair, we use case histories to document how damage and repair processes affect efficient operation of engineered pathways - particularly those that are heterologous, non-natural, or cell-free. We then review how metabolite damage reactions can be predicted, how repair reactions can be prospected, and how metabolite damage and repair can be built into genome-scale metabolic models. Lastly, we propose a versatile 'plug and play' set of well-characterized metabolite repair enzymes to solve metabolite damage problems known or likely to occur in metabolic engineering and synthetic biology projects.« less

  15. Effects of clopidogrel and clarithromycin on the disposition of sibutramine and its active metabolites M1 and M2 in relation to CYP2B6*6 polymorphism.

    PubMed

    Pan, Wei; Bae, Soo-Kyung; Shim, Eon-Jeong; Park, Sung-Eun; Lee, Sang-Seop; Park, Soo-Jin; Yeo, Chang-Woo; Zhou, Hong-Hao; Shon, Ji-Hong; Shin, Jae-Gook

    2013-02-01

    Plasma concentrations of sibutramine and its two active metabolites after single oral dose of sibutramine were determined in Korean healthy male subjects with different CYP2B6 genotypes (CYP2B6*1/*1, *1/*6 and *6/*6), either alone or after four-day pretreatment with clopidogrel or clarithromycin. The pretreatment with clopidogrel and clarithromycin raised the mean area under the concentration-time curve (AUC) of sibutramine by 163% and 255%, respectively. Co-administration of clarithromycin, combined with CYP2B6*6/*6 genotype, led to highest concentration of sibutramine. The molar sum AUC (M1 + M2) was raised by 35% in the clopidogrel phase but not significantly affected by clarithromycin or CYP2B6 genotype. The CYP2B6*6/*6 subjects in the clopidogrel phase showed the highest molar AUC (M1 + M2) among three genotype groups throughout the three phases. The exposure of sibutramine and its metabolites seemed to be associated with the CYP2B6 genotype. The treatment of clopidogrel significantly altered the disposition of active metabolites as well as sibutramine, but clarithromycin only affects the disposition of sibutramine. These results suggest that the perturbation of CYP2B6 activity may contribute to the inter-individual variation of sibutramine drug responses although the clinical relevance is remained to be established.

  16. Tandem mass spectrometric analysis of cyclophosphamide, ifosfamide and their metabolites.

    PubMed

    Liu, Zhongfa; Chan, Kenneth K; Wang, Jeffrey J

    2005-01-01

    A detailed multi-stage (MSn) fragmentation study of cyclophosphamide (CP), ifosfamide (IF) and their major metabolites, using an ion-trap mass spectrometer and a Q-TOF mass spectrometer, was performed with the aid of specifically deuterium-labeled analogs. The analytes showed good responses in positive-ion electrospray mass spectrometry as [MH]+ ions. Tandem mass spectra revealed a wealth of structurally specific ions, allowing characterization of the fragmentation pathways of these analytes. The major fragmentation pathways of the protonated CP and IF are elimination of ethylene from C5 and C6 of 1,3,2-oxazaphosphorine-2-oxide via a McLafferty rearrangement, and cleavage of the P-N bond. However, their activated 4-OOH and 4-OH metabolites primarily underwent hydrogen peroxide elimination and dehydration, respectively, followed by fragmentation pathways similar to those of CP and IF. These results should prove useful in structural elucidation of future analogs of CP and IF, and/or of their metabolites. Copyright (c) 2005 John Wiley & Sons, Ltd.

  17. Role of growth media and chemical enhancers in secondary metabolites production from Aspergillus carbonarius (NRL-369) and their pharmaceutical potentials.

    PubMed

    Khan, Abid Ali; Bacha, Nafess; Ahmad, Bashir; Cox, R J; Bakht, Jehan

    2016-07-01

    The present study investigates the effect of different growth media and chemical enhancer on silent genes in Aspergillus carbonarius (NRL-369) for secondary metabolites production and its in vitro biological activities. Results revealed that Aspergillus carbonarius (NRL-369) grown in Czapeak yeast extract broth medium produced more metabolites compared with other media. Chemical epigenetic modifiers (suberoyl-anilide hydroxamic acid (SAHA) and 5-azacytidine (5-AZA) at concentration of 15mM were effective for the expression of silent genes resulting in increased secondary metabolites production. Secondary metabolites extracted in ethyl acetate and fractionized in n-Hexane showed variable degree of growth inhibitions of the tested microorganisms. Similarly, these samples were also active against brine shrimps and Lemna.

  18. Potential of rare actinomycetes in the production of metabolites against multiple oxidant agents.

    PubMed

    Mohammadipanah, Fatemeh; Momenilandi, Mana

    2018-12-01

    Actinobacteria are a precious source of novel bioactive metabolites with potential pharmaceutical applications. Representatives of 11 genera of rare Actinobacteria were selected for the evaluation of antioxidant activity. Fermentation broths of the Actinobacteria were extracted and dosage of 10 to 2000 µg/mL were applied for in vitro antioxidant-related bioassays. Cytotoxicity was assessed at the concentration of 2.5-20 µg/mL. In the DPPH scavenging activity, 15 out of 52 extracts showed 17.0-26.8% activity in quantitative evaluation. Metabolites of five prominent antioxidant producing strains protected the DNA (pUC19) against UV-induced photolyzed H 2 O 2 -oxidative degradation. The potent antioxidant extracts inhibited two oxidative enzymes of xanthine oxidase in the range of 17.5-45.2% (three extracts had IC 50 less than allopurinol) and lipoxygenase in the range of 36-55% (all five extracts had IC 50 values less than daidzein). All these extracts could also protect eythrocytes from iron-induced hemolysis with ED 50 values in a range of 0.014-1.25 mg/mL. Growth restoration of the yeast cells lacking the sod1 gene was observed by the antioxidant metabolite of Saccharothrix ecbatanensis UTMC 537 at the concentration of 1 mg/mL. The presence of nonidentical metabolites might be responsible for antioxidant and enzyme inhibitory activities of S. ecbatanensis, newly described actinobacterium in family Pseudonocardiaceae. The scavenging of the free electrons, protection of DNA and model yeast cells against oxidative stress, in addition to the inhibition of the oxidating enzymes are the main mechanisms of the antioxidant effect of the introduced resource in this study.

  19. Glucuronic acid and the ethanol metabolite ethyl-glucuronide cause Toll-like receptor 4 activation and enhanced pain

    PubMed Central

    Lewis, Susannah S.; Hutchinson, Mark R.; Zhang, Yingning; Hund, Dana K.; Maier, Steven F.; Rice, Kenner C.; Watkins, Linda R.

    2013-01-01

    We have previously observed that the non-opioid morphine metabolite, morphine-3-glucuronide, enhances pain via a toll-like receptor 4 (TLR4) dependent mechanism. The present studies were undertaken to determine whether TLR4-dependent pain enhancement generalizes to other classes of glucuronide metabolites. In silico modeling predicted that glucuronic acid alone and ethyl glucuronide, a minor but long-lasting ethanol metabolite, would dock to the same MD-2 portion of the TLR4 receptor complex previously characterized as the docking site for morphine-3-glucuronide. Glucuronic acid, ethyl glucuronide and ethanol all caused an increase in TLR4-dependent reporter protein expression in a cell line transfected with TLR4 and associated co-signaling molecules. Glucuronic acid-, ethyl glucuronide-, and ethanol-induced increases in TLR4 signaling were blocked by the TLR4 antagonists LPS-RS and (+)-naloxone. Glucuronic acid and ethyl glucuronide both caused allodynia following intrathecal injection in rats, which was blocked by intrathecal co-administration of the TLR4 antagonist LPS-RS. The finding that ethyl glucuronide can cause TLR4-dependent pain could have implications for human conditions such as hangover headache and alcohol withdrawal hyperalgesia, as well as suggesting that other classes of glucuronide metabolites could have similar effects. PMID:23348028

  20. Insecticidal Potential of Defense Metabolites from Ocimum kilimandscharicum against Helicoverpa armigera

    PubMed Central

    Thulasiram, Hirekodathakallu V.; Kulkarni, Mahesh J.; Giri, Ashok P.

    2014-01-01

    Genus Ocimum contains a reservoir of diverse secondary metabolites, which are known for their defense and medicinal value. However, the defense-related metabolites from this genus have not been studied in depth. To gain deeper insight into inducible defense metabolites, we examined the overall biochemical and metabolic changes in Ocimum kilimandscharicum that occurred in response to the feeding of Helicoverpa armigera larvae. Metabolic analysis revealed that the primary and secondary metabolism of local and systemic tissues in O. kilimandscharicum was severely affected following larval infestation. Moreover, levels of specific secondary metabolites like camphor, limonene and β-caryophyllene (known to be involved in defense) significantly increased in leaves upon insect attack. Choice assays conducted by exposing H. armigera larvae on O. kilimandscharicum and tomato leaves, demonstrated that O. kilimandscharicum significantly deters larval feeding. Further, when larvae were fed on O. kilimandscharicum leaves, average body weight decreased and mortality of the larvae increased. Larvae fed on artificial diet supplemented with O. kilimandscharicum leaf extract, camphor, limonene and β-caryophyllene showed growth retardation, increased mortality rates and pupal deformities. Digestive enzymes of H. armigera - namely, amylase, protease and lipase- showed variable patterns after feeding on O. kilimandscharicum, which implies striving of the larvae to attain required nutrition for growth, development and metamorphosis. Evidently, selected metabolites from O. kilimandscharicum possess significant insecticidal activity. PMID:25098951

  1. A new and fast DLLME-CE method for the enantioselective analysis of zopiclone and its active metabolite after fungal biotransformation.

    PubMed

    de Albuquerque, Nayara Cristina Perez; de Gaitani, Cristiane Masetto; de Oliveira, Anderson Rodrigo Moraes

    2015-05-10

    Zopiclone (ZO) is a chiral drug that undergoes extensive metabolism to N-desmethylzopiclone (N-Des-ZO) and zopiclone-N-oxide (N-Ox-ZO). Pharmacological studies have shown (S)-N-Des-ZO metabolite presents anxiolytic activity and a patent for this metabolite was requested for anxiety treatment and related disorders. In this context, biotransformation employing fungi may be a promising strategy to obtain N-Des-ZO. To perform the biotransformation study in this work, an enantioselective method based on capillary electrophoresis (CE) and dispersive liquid-liquid microextraction (DLLME) was developed. CE analyses were carried out in sodium phosphate buffer (pH 2.5; 50mmolL(-1)) containing 0.5% (w/v) carboxymethyl-β-CD, at a constant voltage of +25kV. DLLME was conducted using 2mL of liquid culture medium pH 9.5. Chloroform (100μL) and methanol (300μL) were employed as extraction and disperser solvent, respectively. After CE and DLLME optimization, the analytical method was fully validated. The method was linear over a concentration range of 90-6000ngmL(-1) for each ZO enantiomer (r>0.999) and 50-1000ngmL(-1) for each N-Des-ZO enantiomer (r>0.998). Absolute recovery of 51 and 82% was achieved for N-Des-ZO and ZO, respectively. The accuracy and precision results agreed with the EMA (European Medicines Agency) guideline, and so did the stability study. Application of the developed method in a biotransformation study was conducted in order to investigate the ability of fungi, belonging to the genus Cunninghamella, in metabolizing ZO chiral drug. Fungi Cunninghamella elegans ATCC 10028B and Cunninghamella echinulata var elegans ATCC 8688A demonstrated to be able to enantioselectively biotransform ZO to its active metabolite, N-Des-ZO. Therefore, the proposed goals of this work, i.e. a fast DLLME-CE method and an outstanding strategy to obtain N-Des-ZO, were successfully attained. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Distinct action of aranidipine and its active metabolite on renal arterioles, with special reference to renal protection.

    PubMed

    Nakamura, A; Hayashi, K; Fujiwara, K; Ozawa, Y; Honda, M; Saruta, T

    2000-06-01

    Aranidipine, a newly developed calcium antagonist, possesses unique pharmacologic characteristics in that its metabolite (M-1) still has antihypertensive action. We examined the effects of both agents on renal microcirculation using the isolated perfused hydronephrotic rat kidney. During norepinephrine-induced constriction, the addition of aranidipine dilated both afferent and efferent arterioles in a dose-dependent manner; at 10(-6) M, 83 +/- 6% and 90 +/- 6% reversal, respectively. In contrast, its active metabolite exerted dilator action predominantly on the afferent arteriole (79 +/- 4% vs. 44 +/- 17% at 10(-6) M for afferent and efferent arterioles, respectively). We further examined the long-term (8 weeks) effect of these agents on the development of renal injury in salt-loaded subtotally nephrectomized spontaneously hypertensive rats. Both aranidipine and M-1 reduced blood pressure by a similar magnitude. The decreases in proteinuria were observed in the aranidipine-treated group at weeks 6, 8, and 10, whereas in the M-1 group, significant reduction was attained only at week 6. Histopathologic examination revealed that both treatments improved glomerular and arteriolar sclerosis. Glomerular sclerosis, however, was less pronounced in the aranidipine-treated group than in the M-1 group. In conclusion, aranidipine has dilator action on both arterioles, whereas M-1 caused predominant dilation of afferent arterioles. Such metabolic changes may constitute a determinant of efferent arteriolar action of the calcium antagonist.

  3. Metabolite fingerprinting, pathway analyses, and bioactivity correlations for plant species belonging to the Cornaceae, Fabaceae, and Rosaceae families.

    PubMed

    Son, Su Young; Kim, Na Kyung; Lee, Sunmin; Singh, Digar; Kim, Ga Ryun; Lee, Jong Seok; Yang, Hee-Sun; Yeo, Joohong; Lee, Sarah; Lee, Choong Hwan

    2016-09-01

    A multi-parallel approach gauging the mass spectrometry-based metabolite fingerprinting coupled with bioactivity and pathway evaluations could serve as an efficacious tool for inferring plant taxonomic orders. Thirty-four species from three plant families, namely Cornaceae (7), Fabaceae (9), and Rosaceae (18) were subjected to metabolite profiling using gas chromatography-time-of-flight-mass spectrometry (GC-TOF-MS) and ultrahigh performance liquid chromatography-linear trap quadrupole-ion trap-mass spectrometry (UHPLC-LTQ-IT-MS/MS), followed by multivariate analyses to determine the metabolites characteristic of these families. The partial least squares discriminant analysis (PLS-DA) revealed the distinct clustering pattern of metabolites for each family. The pathway analysis further highlighted the relatively higher proportions of flavonols and ellagitannins in the Cornaceae family than in the other two families. Higher levels of phenolic acids and flavan-3-ols were observed among species from the Rosaceae family, while amino acids, flavones, and isoflavones were more abundant among the Fabaceae family members. The antioxidant activities of plant extracts were measured using ABTS, DPPH, and FRAP assays, and indicated that extracts from the Rosaceae family had the highest activity, followed by those from Cornaceae and Fabaceae. The correlation map analysis positively links the proportional concentration of metabolites with their relative antioxidant activities, particularly in Cornaceae and Rosaceae. This work highlights the pre-eminence of the multi-parallel approach involving metabolite profiling and bioactivity evaluations coupled with metabolic pathways as an efficient methodology for the evaluation of plant phylogenies.

  4. Functional nucleic acids as in vivo metabolite and ion biosensors.

    PubMed

    Alsaafin, Alaa; McKeague, Maureen

    2017-08-15

    Characterizing the role of metabolites, metals, and proteins is required to understand normal cell function, and ultimately, elucidate the mechanism of disease. Metabolite concentration and transformation results collected from cell lysates or fixed-cells conceal important dynamic information and differences between individual cells that often have profound functional consequences. Functional nucleic acid-based biosensors are emerging tools that are capable of monitoring ions and metabolites in cell populations or whole animals. Functional nucleic acids (FNAs) are a class of biomolecules that can exhibit either ligand binding or enzymatic activity. Unlike their protein analogues or the use of instrument-based analysis, FNA-based biosensors are capable of entering cells without disruption to the cellular environment and can report on the concentration, dynamics, and spatial localization of molecules in cells. Here, we review the types of FNAs that have been used as in vivo biosensors, and how FNAs can be coupled to transduction systems and delivered inside cells. We also provide examples from the literature that demonstrate their impact in practical applications. Finally, we comment on the critical limitations that need to be addressed to enable their use for single-cell dynamic tracking of metabolites and ions in vivo. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

  5. Metabolite monitoring to guide thiopurine therapy in systemic autoimmune diseases.

    PubMed

    Chapdelaine, Aurélie; Mansour, Anne-Marie; Troyanov, Yves; Williamson, David R; Doré, Maxime

    2017-06-01

    6-Thioguanine nucleotide (6-TGN) is the active metabolite of thiopurine drugs azathioprine and 6-mercaptopurine. 6-Methylmercaptopurine (6-MMP) is an inactive and potentially hepatotoxic metabolite. A subgroup of patients (shunters) preferentially produce 6-MMP instead of 6-TGN, therefore displaying thiopurine resistance and risk for hepatotoxicity. Outside inflammatory bowel disease literature, few data exist regarding individualized thiopurine therapy based on metabolite monitoring. This study sought to describe metabolite monitoring in patients receiving weight-based thiopurine for systemic autoimmune diseases. Patients were enrolled using a laboratory database, and data were retrospectively collected. The correlation between the highest thiopurine dose (mg/kg) and the 6-TGN concentration (pmol/8 × 10 8 erythrocytes) was estimated with Pearson's correlation coefficient. Seventy-one patients with various systemic autoimmune conditions were enrolled. The correlation between the thiopurine dose and the 6-TGN level was weak for the overall patient sample (r = 0.201, p = 0.092) and for the subgroup of non-shunters (r = 0.278, p = 0.053). Subjects with 6-MMP levels >5700 pmol/8 × 10 8 erythrocytes had more hepatic cytolysis compared to subjects with 6-MMP <5700, OR = 4.36 (CI 95% 1.18-16.13, p = 0.027). Twenty-two patients (31%) were identified as shunters. Six shunters developed hepatotoxicity, five of which had 6-MMP concentration >5700. Eleven non-shunters had hepatotoxicity, one of which had 6-MMP >5700. Thiopurine metabolite monitoring shows wide variability in 6-TGN levels among patients treated with weight-based thiopurine for systemic autoimmune diseases. Thirty-one percent of the patients in our series fulfilled the shunter definition. Thiopurine metabolite monitoring and dose adjustment to improve maintenance of remission and avoid hepatotoxicity should be studied prospectively.

  6. [Molecular regulation of microbial secondary metabolites--a review].

    PubMed

    Wang, Linqi; Tan, Huarong

    2009-04-01

    Microbial secondary metabolites play an important role in the field of industry, agriculture, medicine and human health. The molecular regulation of secondary metabolites is gradually becoming noticeable and intriguing. In recent years, many researches have demonstrated that secondary metabolite biosynthesis is tightly linked to the physiological and developmental status in its producer. It is suggested that the biosynthesis of secondary metabolites involves in complex process concerning multi-level regulation. Here we reviewed the recent research progress on the molecular regulation of secondary metabolites in microorganisms. In known about ten thousand kinds of natural secondary metabolites, most of them (about 60%) were produced by Streptomycete. Therefore, the regulation of secondary metabolites in Streptomyces is chosen as the mainline in this review. Additionally, several well-studied antibiotics as the representative members were targeted. Finally, some suggestions, in response to the issues at present, have been presented in this paper.

  7. Diclofenac and metabolite pharmacokinetics in children.

    PubMed

    van der Marel, Caroline D; Anderson, Brian J; Rømsing, Janne; Jacqz-Aigrain, Evelyne; Tibboel, Dick

    2004-06-01

    Data concerning metabolism of diclofenac in children are limited to intravenous and enteric coated oral formulations. There are no data examining diclofenac or its hydroxyl metabolite pharmacokinetics after rectal administration in children. Infants (n = 26) undergoing tonsillectomy were given diclofenac 2 mg.kg(-1) followed by 1 mg.kg(-1) 8 h as suppository formulation for postoperative analgesia. Serum was assayed for diclofenac, 4'-hydroxydiclofenac and 5'-hydroxydiclofenac concentrations during the procedure and 1, 2 and 4 h postoperatively. The formation clearances of diclofenac to hydroxyl metabolites were estimated using nonlinear mixed effects models. A single compartment, first order absorption and first order elimination model was used to describe diclofenac pharmacokinetics. Published data from 11 children given enteric-coated diclofenac tablets were used to assess relative bioavailability. Mean (sd) age and weight of the patients were 4.5 (1.5) years and 20.5 (4.1) kg. The formation clearance to 4'-hydroxydiclofenac (% CV) and to 5'-hydroxydiclofenac were 8.41 (8.1) and 3.41 (113) l.h(-1) respectively, standardized to a 70 kg person using allometric '1/4 power' models. Clearance by other routes contributed 33.0 (64) l.h(-1) 70 kg(-1). Elimination clearance of hydroxyl metabolites was fixed at 27.5 l.h(-1) 70 kg(-1). The volumes of distribution of parent diclofenac and its hydroxyl metabolite were 22.8 (19.0) and 45.3 (l.70) kg(-1). The suppository formulation had an absorption half-life of 0.613 (33.2) h with a lag time of 0.188 (24.9) h. Interoccasion variability of formation clearance to 4'-hydroxydiclofenac, diclofenac volume of distribution, absorption half-time and lag time for the suppository was 36%, 55%, 14% and 119%, respectively. The relative bioavailability of the suppository compared with an enteric-coated tablet was 1.26. The formation clearance of the active metabolite 4'-hydroxydiclofenac contributed 19% of total clearance (44.82 l.h(-1

  8. Bioactive Secondary Metabolites Produced by the Fungal Endophytes of Conifers.

    PubMed

    Stierle, Andrea A; Stierle, Donald B

    2015-10-01

    This is a review of bioactive secondary metabolites isolated from conifer-associated endophytic fungi from 1990-2014. This includes compounds with antimicrobial, anti-inflammatory, anti-proliferative and cytotoxic activity towards human cancer cell lines, and activity against either plant pathogens or plant insect pests. Compounds that were originally reported without associated activity were included if other studies ascribed activity to these compounds. Compounds were not included if they were exclusively phytotoxic or if they were isolated from active extracts but were not determined to be the active component of that extract.

  9. Metabolic regulation and overproduction of primary metabolites

    PubMed Central

    Sanchez, Sergio; Demain, Arnold L.

    2008-01-01

    Summary Overproduction of microbial metabolites is related to developmental phases of microorganisms. Inducers, effectors, inhibitors and various signal molecules play a role in different types of overproduction. Biosynthesis of enzymes catalysing metabolic reactions in microbial cells is controlled by well‐known positive and negative mechanisms, e.g. induction, nutritional regulation (carbon or nitrogen source regulation), feedback regulation, etc. The microbial production of primary metabolites contributes significantly to the quality of life. Fermentative production of these compounds is still an important goal of modern biotechnology. Through fermentation, microorganisms growing on inexpensive carbon and nitrogen sources produce valuable products such as amino acids, nucleotides, organic acids and vitamins which can be added to food to enhance its flavour, or increase its nutritive values. The contribution of microorganisms goes well beyond the food and health industries with the renewed interest in solvent fermentations. Microorganisms have the potential to provide many petroleum‐derived products as well as the ethanol necessary for liquid fuel. Additional applications of primary metabolites lie in their impact as precursors of many pharmaceutical compounds. The roles of primary metabolites and the microbes which produce them will certainly increase in importance as time goes on. In the early years of fermentation processes, development of producing strains initially depended on classical strain breeding involving repeated random mutations, each followed by screening or selection. More recently, methods of molecular genetics have been used for the overproduction of primary metabolic products. The development of modern tools of molecular biology enabled more rational approaches for strain improvement. Techniques of transcriptome, proteome and metabolome analysis, as well as metabolic flux analysis. have recently been introduced in order to identify new and

  10. A metabolite-centric view on flux distributions in genome-scale metabolic models

    PubMed Central

    2013-01-01

    Background Genome-scale metabolic models are important tools in systems biology. They permit the in-silico prediction of cellular phenotypes via mathematical optimisation procedures, most importantly flux balance analysis. Current studies on metabolic models mostly consider reaction fluxes in isolation. Based on a recently proposed metabolite-centric approach, we here describe a set of methods that enable the analysis and interpretation of flux distributions in an integrated metabolite-centric view. We demonstrate how this framework can be used for the refinement of genome-scale metabolic models. Results We applied the metabolite-centric view developed here to the most recent metabolic reconstruction of Escherichia coli. By compiling the balance sheets of a small number of currency metabolites, we were able to fully characterise the energy metabolism as predicted by the model and to identify a possibility for model refinement in NADPH metabolism. Selected branch points were examined in detail in order to demonstrate how a metabolite-centric view allows identifying functional roles of metabolites. Fructose 6-phosphate aldolase and the sedoheptulose bisphosphate bypass were identified as enzymatic reactions that can carry high fluxes in the model but are unlikely to exhibit significant activity in vivo. Performing a metabolite essentiality analysis, unconstrained import and export of iron ions could be identified as potentially problematic for the quality of model predictions. Conclusions The system-wide analysis of split ratios and branch points allows a much deeper insight into the metabolic network than reaction-centric analyses. Extending an earlier metabolite-centric approach, the methods introduced here establish an integrated metabolite-centric framework for the interpretation of flux distributions in genome-scale metabolic networks that can complement the classical reaction-centric framework. Analysing fluxes and their metabolic context simultaneously opens

  11. Structural characterization of a therapeutic anti-methamphetamine antibody fragment: oligomerization and binding of active metabolites.

    PubMed

    Peterson, Eric C; Celikel, Reha; Gokulan, Kuppan; Varughese, Kottayil I

    2013-01-01

    Vaccines and monoclonal antibodies (mAb) for treatment of (+)-methamphetamine (METH) abuse are in late stage preclinical and early clinical trial phases, respectively. These immunotherapies work as pharmacokinetic antagonists, sequestering METH and its metabolites away from sites of action in the brain and reduce the rewarding and toxic effects of the drug. A key aspect of these immunotherapy strategies is the understanding of the subtle molecular interactions important for generating antibodies with high affinity and specificity for METH. We previously determined crystal structures of a high affinity anti-METH therapeutic single chain antibody fragment (scFv6H4, K(D) = 10 nM) in complex with METH and the (+) stereoisomer of 3,4-methylenedioxymethamphetamine (MDMA, or "ecstasy"). Here we report the crystal structure of scFv6H4 in homo-trimeric unbound (apo) form (2.60Å), as well as monomeric forms in complex with two active metabolites; (+)-amphetamine (AMP, 2.38Å) and (+)-4-hydroxy methamphetamine (p-OH-METH, 2.33Å). The apo structure forms a trimer in the crystal lattice and it results in the formation of an intermolecular composite beta-sheet with a three-fold symmetry. We were also able to structurally characterize the coordination of the His-tags with Ni(2+). Two of the histidine residues of each C-terminal His-tag interact with Ni(2+) in an octahedral geometry. In the apo state the CDR loops of scFv6H4 form an open conformation of the binding pocket. Upon ligand binding, the CDR loops adopt a closed formation, encasing the drug almost completely. The structural information reported here elucidates key molecular interactions important in anti-methamphetamine abuse immunotherapy.

  12. Bioactivation of loxoprofen to a pharmacologically active metabolite and its disposition kinetics in human skin.

    PubMed

    Sawamura, Ryoko; Sakurai, Hidetaka; Wada, Naoya; Nishiya, Yumi; Honda, Tomoyo; Kazui, Miho; Kurihara, Atsushi; Shinagawa, Akira; Izumi, Takashi

    2015-09-01

    Loxoprofen (LX) is a prodrug-type non-steroidal anti-inflammatory drug which is used not only as an oral drug but also as a transdermal formulation. As a pharmacologically active metabolite, the trans-alcohol form of LX (trans-OH form) is generated after oral administration to humans. The objectives of this study were to evaluate the generation of the trans-OH form in human in vitro skin and to identify the predominant enzyme for its generation. In the permeation and metabolism study using human in vitro skin, both the permeation of LX and the formation of the trans-OH form increased in a time- and dose-dependent manner after the application of LX gel to the skin. In addition, the characteristics of permeation and metabolism of both LX and the trans-OH form were examined by a mathematical pharmacokinetic model. The K m value was calculated to be 10.3 mm in the human in vitro skin. The predominant enzyme which generates the trans-OH form in human whole skin was identified to be carbonyl reductase 1 (CBR1) by immunodepletion using the anti-human CBR1 antibody. The results of the enzyme kinetic study using the recombinant human CBR1 protein demonstrated that the K m and V max values were 7.30 mm and 402 nmol/min/mg protein, respectively. In addition, it was found that no unknown metabolites were generated in the human in vitro skin. This is the first report in which LX is bioactivated to the trans-OH form in human skin by CBR1. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

  13. Effect of sublethal preculturing on the survival of probiotics and metabolite formation in set-yoghurt.

    PubMed

    Settachaimongkon, Sarn; van Valenberg, Hein J F; Winata, Vera; Wang, Xiaoxi; Nout, M J Robert; van Hooijdonk, Toon C M; Zwietering, Marcel H; Smid, Eddy J

    2015-08-01

    The objective of this study was to investigate the effect of preculturing of Lactobacillus rhamnosus GG and Bifidobacterium animalis subsp. lactis BB12 under sublethal stress conditions on their survival and metabolite formation in set-yoghurt. Prior to co-cultivation with yoghurt starters in milk, the two probiotic strains were precultured under sublethal stress conditions (combinations of elevated NaCl and low pH) in a batch fermentor. The activity of sublethally precultured probiotics was evaluated during fermentation and refrigerated storage by monitoring bacterial population dynamics, milk acidification and changes in volatile and non-volatile metabolite profiles of set-yoghurt. The results demonstrated adaptive stress responses of the two probiotic strains resulting in their viability improvement without adverse influence on milk acidification. A complementary metabolomic approach using SPME-GC/MS and (1)H-NMR resulted in the identification of 35 volatiles and 43 non-volatile polar metabolites, respectively. Principal component analysis revealed substantial impact of the activity of sublethally precultured probiotics on metabolite formation demonstrated by distinctive volatile and non-volatile metabolite profiles of set-yoghurt. Changes in relative abundance of various aroma compounds suggest that incorporation of stress-adapted probiotics considerably influences the organoleptic quality of product. This study provides new information on the application of stress-adapted probiotics in an actual food-carrier environment. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Neuropharmacological and neuroprotective activities of some metabolites produced by cell suspension culture of Waltheria americana Linn.

    PubMed

    Mundo, Jorge; Villeda-Hernández, Juana; Herrera-Ruiz, Maribel; Gutiérrez, María Del Carmen; Arellano-García, Jesús; León-Rivera, Ismael; Perea-Arango, Irene

    2017-10-01

    Waltheria americana is a plant used in Mexican traditional medicine to treat some nervous system disorders. The aims of the present study were to isolate and determine the neuropharmacological and neurprotective activities of metabolites produced by a cell suspension culture of Waltheria americana. Submerged cultivation of W. americana cells provided biomass. A methanol-soluble extract (WAsc) was obtained from biomass. WAsc was fractionated yielding the chromatographic fractions 4WAsc-H 2 O and WAsc-CH 2 Cl 2 . For the determination of anticonvulsant activity in vivo, seizures were induced in mice by pentylenetetrazol (PTZ). Neuropharmacological activities (release of gamma amino butyric acid (GABA) and neuroprotection) of chromatographic fractions were determined by in vitro histological analysis of brain sections of mice post mortem. Fraction 4WAsc-H 2 O (containing saccharides) did not produce neuronal damage, neurodegeneration, interstitial tissue edema, astrocytic activation, nor cell death. Pretreatment of animals with 4WAsc-H 2 O and WAsc-CH 2 Cl 2 from W. americana cell suspensions induced an increase in: GABA release, seizure latency, survival time, neuroprotection, and a decrease in the degree of severity of tonic/tonic-clonic convulsions, preventing PTZ-induced death of up to 100% of animals of study. Bioactive compounds produced in suspension cell culture of W. americana produce neuroprotective and neuropharmacological activities associated with the GABAergic neurotransmission system. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  15. Metabolite profiling and bioactivity of rice koji fermented by Aspergillus strains.

    PubMed

    Kim, Ah-Jin; Choi, Jung-Nam; Kim, Jiyoung; Kim, Hyang Yeon; Park, Sait-Byul; Yeo, Soo-Hwan; Choi, Ji-Ho; Liu, Kwang-Hyeon; Lee, Choong Hwan

    2012-01-01

    In this study, the metabolite profiles of three Aspergillus strains during rice koji fermentation were compared. In the partial least squares discriminant analysis-based gas chromatography-mass spectrometry data sets, the metabolite patterns of A. oryzae (KCCM 60345) were clearly distinguished from A. kawachii (KCCM 60552) and only marginal differences were observed for A. oryzae (KCCM 60551) fermentation. In the 2 days fermentation samples, the overall metabolite levels of A. oryzae (KCCM 60345) were similar to the A. oryzae (KCCM 60551) levels and lower than the A. kawachii (KCCM 60552) levels. In addition, we identified discriminators that were mainly contributing tyrosinase inhibition (kojic acid) and antioxidant activities (pyranonigrin A) in A. oryzae (KCCM 60345) and A. kawachii (KCCM 60552) inoculated rice koji, respectively. In this study, we demonstrated that the optimal inoculant Aspergillus strains and fermentation time for functional rice koji could be determined through a metabolomics approach with bioactivity correlations.

  16. Potential antiproliferative activity of polyphenol metabolites against human breast cancer cells and their urine excretion pattern in healthy subjects following acute intake of a polyphenol-rich juice of grumixama (Eugenia brasiliensis Lam.).

    PubMed

    Teixeira, L L; Costa, G R; Dörr, F A; Ong, T P; Pinto, E; Lajolo, F M; Hassimotto, N M A

    2017-06-21

    The bioavailability and metabolism of anthocyanins and ellagitannins following acute intake of grumixama fruit, native Brazilian cherry, by humans, and its in vitro antiproliferative activity against breast cancer cells (MDA-MB-231) were investigated. A single dose of grumixama juice was administered to healthy women (n = 10) and polyphenol metabolites were analyzed in urine and plasma samples collected over 24 h. The majority of the metabolites circulating and excreted in urine were phenolic acids and urolithin conjugates, the gut microbiota catabolites of both classes of polyphenols, respectively. According to pharmacokinetic parameters, the subjects were divided into two distinct groups, high and low urinary metabolite excretors. The pool of polyphenol metabolites found in urine samples showed a significant inhibition of cell proliferation and G2/M cell cycle arrest in MDA-MB-231 cells. Our findings demonstrate the large interindividual variability concerning the polyphenol metabolism, which possibly could reflect in health promotion.

  17. A sensitive and rapid ultra HPLC-MS/MS method for the simultaneous detection of clopidogrel and its derivatized active thiol metabolite in human plasma.

    PubMed

    Peer, Cody J; Spencer, Shawn D; VanDenBerg, Dustin A H; Pacanowski, Michael A; Horenstein, Richard B; Figg, William D

    2012-01-01

    A sensitive, selective, and rapid ultra-high performance liquid chromatography-tandem mass spectrometry (uHPLC-MS/MS) was developed for the simultaneous quantification of clopidogrel (Plavix(®)) and its derivatized active metabolite (CAMD) in human plasma. Derivatization of the active metabolite in blood with 2-bromo-3'-methoxy acetophenone (MPB) immediately after collection ensured metabolite stability during sample handling and storage. Following addition of ticlopidine as an internal standard and simple protein precipitation, the analytes were separated on a Waters Acquity UPLC™ sub-2 μm-C(18) column via gradient elution before detection on a triple-quadrupole MS with multiple-reaction-monitoring via electrospray ionization. The method was validated across the clinically relevant concentration range of 0.01-50 ng/mL for parent clopidogrel and 0.1-150 ng/mL (r(2)=0.99) for CAMD, with a fast run time of 1.5 min to support pharmacokinetic studies using 75, 150, or 300 mg oral doses of clopidogrel. The analytical method measured concentrations of clopidogrel and CAMD with accuracy (%DEV) <±12% and precision (%CV) of <±6%. The method was successfully applied to measure the plasma concentrations of clopidogrel and CAMD in three subjects administered single oral doses of 75, 150, and 300 mg clopidogrel. It was further demonstrated that the derivatizing agent (MPB) does not affect clopidogrel levels, thus from one aliquot of blood drawn clinically, this method can simultaneously quantify both clopidogrel and CAMD with sensitivity in the picogram per mL range. Published by Elsevier B.V.

  18. A Sensitive and Rapid Ultra HPLC-MS/MS Method for the Simultaneous Detection of Clopidogrel and its Derivatized Active Thiol Metabolite in Human Plasma

    PubMed Central

    Peer, Cody J.; Spencer, Shawn D.; VanDenBerg, Dustin A. H.; Pacanowski, Michael A.; Horenstein, Richard B.; Figg, William D.

    2011-01-01

    A sensitive, selective, and rapid ultra-high performance liquid chromatography-tandem mass spectrometry (uHPLC-MS/MS) was developed for the simultaneous quantification of clopidogrel (Plavix®) and its derivatized active metabolite (CAMD) in human plasma. Derivatization of the active metabolite in blood with 2-bromo-3’-methoxy acetophenone (MPB) immediately after collection ensured metabolite stability during sample handling and storage. Following addition of ticlopidine as an internal standard and simple protein precipitation, the analytes were separated on a Waters Acquity UPLC™ sub-2µm-C18 column via gradient elution before detection on a triple-quadrupole MS with multiple-reaction-monitoring via electrospray ionization. The method was validated across the clinically-relevant concentration range of 0.01–50 ng/mL for parent clopidogrel and 0.1–150 ng/mL (r2= 0.99) for CAMD, with a fast run time of 1.5 min to support pharmacokinetic studies using 75, 150, or 300 mg oral doses of clopidogrel. The analytical method measured concentrations of clopidogrel and CAMD with accuracy (%DEV) < ±12% and precision (%CV) of < ±6%. The method was successfully applied to measure the plasma concentrations of clopidogrel and CAMD in three subjects administered single oral doses of 75, 150, and 300 mg clopidogrel. It was further demonstrated that the derivatizing agent (MPB) does not affect clopidogrel levels, thus from one aliquot of blood drawn clinically, this method can simultaneously quantify both clopidogrel and CAMD with sensitivity in the picogram per mL range. PMID:22169056

  19. Secondary metabolites from Eurotium species, Aspergillus calidoustus and A. insuetus common in Canadian homes with a review of their chemistry and biological activities.

    PubMed

    Slack, Gregory J; Puniani, Eva; Frisvad, Jens C; Samson, Robert A; Miller, J David

    2009-04-01

    As part of studies of metabolites from fungi common in the built environment in Canadian homes, we investigated metabolites from strains of three Eurotium species, namely E. herbariorum, E. amstelodami, and E. rubrum as well as a number of isolates provisionally identified as Aspergillus ustus. The latter have been recently assigned as the new species A. insuetus and A. calidoustus. E. amstelodami produced neoechinulin A and neoechinulin B, epiheveadride, flavoglaucin, auroglaucin, and isotetrahydroauroglaucin as major metabolites. Minor metabolites included echinulin, preechinulin and neoechinulin E. E. rubrum produced all of these metabolites, but epiheveadride was detected as a minor metabolite. E. herbariorum produced cladosporin as a major metabolite, in addition to those found in E. amstelodami. This species also produced questin and neoechinulin E as minor metabolites. This is the first report of epiheveadride occurring as a natural product, and the first nonadride isolated from Eurotium species. Unlike strains from mainly infection-related samples, largely from Europe, neither ophiobolins G and H nor austins were detected in the Canadian strains of A. insuetus and A. calidoustus tested, all of which had been reported from the latter species. TMC-120 A, B, C and a sesquiterpene drimane are reported with certainty for the first time from indoor isolates, as well as two novel related methyl isoquinoline alkaloids.

  20. Antibacterial, antifungal, and antiviral activities of the lipophylic extracts of Pistacia vera.

    PubMed

    Ozçelik, Berrin; Aslan, Mustafa; Orhan, Ilkay; Karaoglu, Taner

    2005-01-01

    In the present study, antibacterial, antifungal, and antiviral properties of 15 lipohylic extracts obtained from different parts (leaf, branch, stem, kernel, shell skins, seeds) of Pistacia vera were screened against both standard and the isolated strains of Escherichia coli, Pseudomonas aeruginosa, Enterococcus faecalis, Staphylococcus aureus, Candida albicans and C. parapsilosis by microdilution method. Both Herpes simplex (DNA) and Parainfluenza viruses (RNA) were used for the determination of antiviral activity of the P. vera extracts by using Vero cell line. Ampicilline, ofloxocine, ketoconazole, fluconazole, acyclovir and oseltamivir were used as the control agents. The extracts showed little antibacterial activity between the range of 128-256 microg/ml concentrations whereas they had noticeable antifungal activity at the same concentrations. Kernel and seed extracts showed significant antiviral activity compared to the rest of the extracts as well as the controls.

  1. An ultra performance liquid chromatography-tandem MS assay for tamoxifen metabolites profiling in plasma: first evidence of 4'-hydroxylated metabolites in breast cancer patients.

    PubMed

    Dahmane, E; Mercier, T; Zanolari, B; Cruchon, S; Guignard, N; Buclin, T; Leyvraz, S; Zaman, K; Csajka, C; Decosterd, L A

    2010-12-15

    There is increasing evidence that the clinical efficacy of tamoxifen, the first and most widely used targeted therapy for estrogen-sensitive breast cancer, depends on the formation of the active metabolites 4-hydroxy-tamoxifen and 4-hydroxy-N-desmethyl-tamoxifen (endoxifen). Large inter-individual variability in endoxifen plasma concentrations has been observed and related both to genetic and environmental (i.e. drug-induced) factors altering CYP450s metabolizing enzymes activity. In this context, we have developed an ultra performance liquid chromatography-tandem mass spectrometry method (UPLC-MS/MS) requiring 100 μL of plasma for the quantification of tamoxifen and three of its major metabolites in breast cancer patients. Plasma is purified by a combination of protein precipitation, evaporation at room temperature under nitrogen, and reconstitution in methanol/20 mM ammonium formate 1:1 (v/v), adjusted to pH 2.9 with formic acid. Reverse-phase chromatographic separation of tamoxifen, N-desmethyl-tamoxifen, 4-hydroxy-tamoxifen and 4-hydroxy-N-desmethyl-tamoxifen is performed within 13 min using elution with a gradient of 10 mM ammonium formate and acetonitrile, both containing 0.1% formic acid. Analytes quantification, using matrix-matched calibration samples spiked with their respective deuterated internal standards, is performed by electrospray ionization-triple quadrupole mass spectrometry using selected reaction monitoring detection in the positive mode. The method was validated according to FDA recommendations, including assessment of relative matrix effects variability, as well as tamoxifen and metabolites short-term stability in plasma and whole blood. The method is precise (inter-day CV%: 2.5-7.8%), accurate (-1.4 to +5.8%) and sensitive (lower limits of quantification comprised between 0.4 and 2.0 ng/mL). Application of this method to patients' samples has made possible the identification of two further metabolites, 4'-hydroxy-tamoxifen and 4'-hydroxy

  2. Yeast synthetic biology for high-value metabolites.

    PubMed

    Dai, Zhubo; Liu, Yi; Guo, Juan; Huang, Luqi; Zhang, Xueli

    2015-02-01

    Traditionally, high-value metabolites have been produced through direct extraction from natural biological sources which are inefficient, given the low abundance of these compounds. On the other hand, these high-value metabolites are usually difficult to be synthesized chemically, due to their complex structures. In the last few years, the discovery of genes involved in the synthetic pathways of these metabolites, combined with advances in synthetic biology tools, has allowed the construction of increasing numbers of yeast cell factories for production of these metabolites from renewable biomass. This review summarizes recent advances in synthetic biology in terms of the use of yeasts as microbial hosts for the identification of the pathways involved in the synthesis, as well as for the production of high-value metabolites. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permission@oup.com.

  3. Assessment of Mexican Arnica (Heterotheca inuloides Cass) and Rosemary (Rosmarinus officinalis) Extracts on Dopamine and Selected Biomarkers of Oxidative Stress in Stomach and Brain of Salmonella typhimurium Infected rats.

    PubMed

    Guzmàn, David Calderón; Herrera, Maribel Ortiz; Brizuela, Norma Osnaya; Mejía, Gerardo Barragàn; García, Ernestina Hernàndez; Olguín, Hugo Juàrez; Peraza, Armando Valenzuela; Ruíz, Norma Labra; Del Angel, Daniel Santamaría

    2017-01-01

    The effects of some natural products on dopamine (DA) and 5-hydroxyindole acetic acid (5-HIAA) in brain of infected models are still unclear. The purpose of this study was to measure the effect of Mexican arnica/rosemary (MAR) water extract and oseltamivir on both biogenic amines and some oxidative biomarkers in the brain and stomach of young rats under infection condition. Female Wistar rats (weight 80 g) in the presence of MAR or absence (no-MAR) were treated as follows: group 1, buffer solution (controls); oseltamivir (100 mg/kg), group 2; culture of Salmonella typhimurium ( S.Typh ) (1 × 10 6 colony-forming units/rat) group 3; oseltamivir (100 mg/kg) + S.Typh (same dose) group 4. Drug and extracts were administered intraperitoneally every 24 h for 5 days, and S.Typh was given orally on days 1 and 3. On the fifth day, blood was collected to measure glucose and hemoglobin. The brains and stomachs were obtained to measure levels of DA, 5-HIAA, glutathione (GSH), TBARS, H 2 O 2 , and total ATPase activity using validated methods. DA levels increased in MAR group treated with oseltamivir alone but decreased in no-MAR group treated with oseltamivir plus S.Typh . 5-HIAA, GSH, and H 2 O 2 decreased in this last group, and ATPase activity increased in MAR group treated with oseltamivir plus S.Typh . TBARS (lipid peroxidation) increased in MAR group that received oseltamivir alone. Most of the biomarkers were not altered significantly in the stomach. MAR extract alters DA and metabolism of 5-HIAA in the brain of young animals infected. Antioxidant capacity may be involved in these effects. The purpose of this study was to measure the effect of Mexican arnica/rosemary water extract and oseltamivir on both biogenic amines and some oxidative biomarkers in the brain and stomach of young rats under infection condition. Results: Mexican arnica and rosemary extract alter dopamine and metabolism of 5-HIAA in the brain of young animals infected. Antioxidant capacity may be

  4. Assessment of Mexican Arnica (Heterotheca inuloides Cass) and Rosemary (Rosmarinus officinalis) Extracts on Dopamine and Selected Biomarkers of Oxidative Stress in Stomach and Brain of Salmonella typhimurium Infected rats

    PubMed Central

    Guzmàn, David Calderón; Herrera, Maribel Ortiz; Brizuela, Norma Osnaya; Mejía, Gerardo Barragàn; García, Ernestina Hernàndez; Olguín, Hugo Juàrez; Peraza, Armando Valenzuela; Ruíz, Norma Labra; Del Angel, Daniel Santamaría

    2017-01-01

    Background: The effects of some natural products on dopamine (DA) and 5-hydroxyindole acetic acid (5-HIAA) in brain of infected models are still unclear. Objective: The purpose of this study was to measure the effect of Mexican arnica/rosemary (MAR) water extract and oseltamivir on both biogenic amines and some oxidative biomarkers in the brain and stomach of young rats under infection condition. Methods: Female Wistar rats (weight 80 g) in the presence of MAR or absence (no-MAR) were treated as follows: group 1, buffer solution (controls); oseltamivir (100 mg/kg), group 2; culture of Salmonella typhimurium (S.Typh) (1 × 106 colony-forming units/rat) group 3; oseltamivir (100 mg/kg) + S.Typh (same dose) group 4. Drug and extracts were administered intraperitoneally every 24 h for 5 days, and S.Typh was given orally on days 1 and 3. On the fifth day, blood was collected to measure glucose and hemoglobin. The brains and stomachs were obtained to measure levels of DA, 5-HIAA, glutathione (GSH), TBARS, H2O2, and total ATPase activity using validated methods. Results: DA levels increased in MAR group treated with oseltamivir alone but decreased in no-MAR group treated with oseltamivir plus S.Typh. 5-HIAA, GSH, and H2O2 decreased in this last group, and ATPase activity increased in MAR group treated with oseltamivir plus S.Typh. TBARS (lipid peroxidation) increased in MAR group that received oseltamivir alone. Most of the biomarkers were not altered significantly in the stomach. Conclusion: MAR extract alters DA and metabolism of 5-HIAA in the brain of young animals infected. Antioxidant capacity may be involved in these effects. SUMMARY The purpose of this study was to measure the effect of Mexican arnica/rosemary water extract and oseltamivir on both biogenic amines and some oxidative biomarkers in the brain and stomach of young rats under infection condition. Results: Mexican arnica and rosemary extract alter dopamine and metabolism of 5-HIAA in the brain of young

  5. Metabolites from invasive pests inhibit mitochondrial complex II: A potential strategy for the treatment of human ovarian carcinoma?

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

    Ferramosca, Alessandra, E-mail: alessandra.ferramosca@unisalento.it; Conte, Annalea; Guerra, Flora

    The red pigment caulerpin, a secondary metabolite from the marine invasive green algae Caulerpa cylindracea can be accumulated and transferred along the trophic chain, with detrimental consequences on biodiversity and ecosystem functioning. Despite increasing research efforts to understand how caulerpin modifies fish physiology, little is known on the effects of algal metabolites on mammalian cells. Here we report for the first time the mitochondrial targeting activity of both caulerpin, and its closely related derivative caulerpinic acid, by using as experimental model rat liver mitochondria, a system in which bioenergetics mechanisms are not altered. Mitochondrial function was tested by polarographic andmore » spectrophotometric methods. Both compounds were found to selectively inhibit respiratory complex II activity, while complexes I, III, and IV remained functional. These results led us to hypothesize that both algal metabolites could be used as antitumor agents in cell lines with defects in mitochondrial complex I. Ovarian cancer cisplatin-resistant cells are a good example of cell lines with a defective complex I function on which these molecules seem to have a toxic effect on proliferation. This provided novel insight toward the potential use of metabolites from invasive Caulerpa species for the treatment of human ovarian carcinoma cisplatin-resistant cells. -- Highlights: •Novel insight toward the potential use of the algal metabolites for the treatment of human diseases. •Caulerpin and caulerpinic acid inhibit respiratory complex II activity. •Both algal metabolites could be used as antitumor agents in ovarian cancer cisplatin-resistant cells.« less

  6. Application of antibody-mediated extraction for the stereoselective determination of the active metabolite of loxoprofen in human and rat plasma.

    PubMed

    Takasaki, W; Tanaka, Y

    1992-01-01

    Antibody-mediated extraction followed by chiral high-performance liquid chromatography (HPLC) was applied to stereoselective determination in human and rat plasma of the active metabolite [(2S,1'R,2'S)-trans-alcohol] with three chiral centers of Loxoprofen, a 2-arylpropionic acid antiinflammatory agent after oral administration. Antiserum against the (1'R,2'S)-cyclopentanol moiety was obtained from a rabbit immunized with bovine serum albumin conjugate linked to the propionic acid moiety, in which another chiral center is located. Then, the immunoglobulin G purified by a protein A column was coupled to BrCN-activated Sepharose 4B. Plasma samples were applied to the immobilized antibody column. After washing the column to remove unrequired stereoisomers, a mixture of two diastereomers whose configurations were 1'R,2'S in the cyclopentanol moiety was extracted with 95% methanol. The solvent was evaporated and the residue was derivatized with (+)-(R)-1-(1-naphthyl)ethylamine as a chiral reagent to separate the diastereomers by HPLC. This combined analytical method showed the stereoselective metabolism of Loxoprofen in human, that is, 64% of the total amount of four trans-alcohol stereoisomers was in the 2S,1'R,2'S form, which is the active metabolite. This phenomenon was also observed in rats given Loxoprofen and its (2S)- and (2R)-isomers, and is explained by stereoselective ketone reduction of Loxoprofen to the (1'R,2'S)-trans-alcohol and inversion from 2R to 2S in the propionic acid moiety. Antibody-mediated extraction should be a selective and simple clean-up method for determining haptens with complicated structures, combined with an appropriate analytical method.

  7. Differential levels of metabolites and enzymes related to aroma formation in aromatic indica rice varieties: comparison with non-aromatic varieties.

    PubMed

    Ghosh, Puja; Roychoudhury, Aryadeep

    2018-01-01

    Accounting for aroma production in different aromatic indica rice varieties based on variations in the levels of concerned metabolites and enzymes is poorly explored. The present investigation was, therefore, focused on unraveling the differential levels of metabolites and activities of enzymes related to aroma formation in eleven indigenous aromatic rice varieties, as compared with four non-aromatic varieties. The levels of metabolites such as proline (Pro) and Δ 1 -pyrroline-5-carboxylate (P5C), and the activity of related enzymes such as proline dehydrogenase (PDH), Δ 1 -pyrroline-5-carboxylate synthetase (P5CS), and ornithine aminotransferase (OAT) were comparatively higher in the aromatic varieties, with Kalonunia and Tulaipanji registering the highest Pro, Kalonunia the highest P5C content, Gobindobhog with the highest PDH activity, Gobindobhog and Tulaipanji with the highest P5CS, and Pusa Basmati-1 with the highest OAT activity. The levels of putrescine (Put) and γ-aminobutyric acid (GABA) were comparatively lower in aromatic varieties, with concomitant higher diamine oxidase (DAO) activity, especially in the varieties Gobindobhog and Tulaipanji. The betaine-aldehyde dehydrogenase 2 (BADH2) enzyme activity was remarkably lesser in aromatic varieties, especially Radhunipagal and Gobindobhog. Though the metabolites such as glycine-betaine and higher polyamines such as spermidine and spermine showed no specific trend with respect to their quantitative level in either aromatic or non-aromatic varieties, they were notably lower in the aromatic varieties such as Gobindobhog, Kalonunia, and Tulaipanji, indicating a possibility of their involvement in aroma formation. Therefore, the levels of metabolites such as Pro, P5C and methylglyoxal (MG), and the activity of enzymes such as PDH, P5CS, OAT, and DAO were comparatively higher in the aromatic rice varieties than the non-aromatic ones, whereas the levels of Put, GABA, and BADH2 were lower. Overall, the present

  8. Production of Bioactive Secondary Metabolites by Marine Vibrionaceae

    PubMed Central

    Mansson, Maria; Gram, Lone; Larsen, Thomas O.

    2011-01-01

    Bacteria belonging to the Vibrionaceae family are widespread in the marine environment. Today, 128 species of vibrios are known. Several of them are infamous for their pathogenicity or symbiotic relationships. Despite their ability to interact with eukaryotes, the vibrios are greatly underexplored for their ability to produce bioactive secondary metabolites and studies have been limited to only a few species. Most of the compounds isolated from vibrios so far are non-ribosomal peptides or hybrids thereof, with examples of N-containing compounds produced independent of nonribosomal peptide synthetases (NRPS). Though covering a limited chemical space, vibrios produce compounds with attractive biological activities, including antibacterial, anticancer, and antivirulence activities. This review highlights some of the most interesting structures from this group of bacteria. Many compounds found in vibrios have also been isolated from other distantly related bacteria. This cosmopolitan occurrence of metabolites indicates a high incidence of horizontal gene transfer, which raises interesting questions concerning the ecological function of some of these molecules. This account underlines the pending potential for exploring new bacterial sources of bioactive compounds and the challenges related to their investigation. PMID:22131950

  9. Effect of Food on the Single-dose Pharmacokinetics and Tolerability of Subutinib and its Active Metabolite in Chinese Healthy Volunteers.

    PubMed

    Ding, L-K; Jia, N; Yang, L; Li, J-K; Song, W; Wang, M-H; Wang, C; Gao, X-H; Wen, A-D

    2016-03-01

    The aim of this study is to investigate a food effect on the single-dose pharmacokinetics and tolerability of subutinib maleate capsules in healthy Chinese volunteers. The author evaluated the effect of being under a fasting or fed state at the time of drug intake on the single-dose of subutinib maleate capsules in a randomized, balanced, single-dose, 2-treatment (fasting and fed), 2-period design with a 3-week washout period. The end points were the maximum plasma drug concentration (Cmax) and areas under the plasma-concentration curve (AUC) for 336 h exposure (AUC0-336) and total exposure (AUC0-∞). All volunteers completed the whole study without side effects being observed. For subutinib, Cmax were 6.13 and 5.04 ng·mL(-1), and AUC0-336 were 278.4 and 304.5 h·ng·mL(-1) in the fasting and the fed state, respectively. For active metabolite, Cmax were 0.90 and 0.61 ng·mL(-1), and AUC0-336 were 65.5 and 56.4 h·ng·mL(-1) in the fasting and the fed state, respectively. The authors showed that food intake was associated with a slight increase in AUC values but decrease in Cmax of subutinib, and it was associated with a decrease both in AUC and Cmax of active metabolite. © Georg Thieme Verlag KG Stuttgart · New York.

  10. Hydrophobicity and Charge Shape Cellular Metabolite Concentrations

    PubMed Central

    Bar-Even, Arren; Noor, Elad; Flamholz, Avi; Buescher, Joerg M.; Milo, Ron

    2011-01-01

    What governs the concentrations of metabolites within living cells? Beyond specific metabolic and enzymatic considerations, are there global trends that affect their values? We hypothesize that the physico-chemical properties of metabolites considerably affect their in-vivo concentrations. The recently achieved experimental capability to measure the concentrations of many metabolites simultaneously has made the testing of this hypothesis possible. Here, we analyze such recently available data sets of metabolite concentrations within E. coli, S. cerevisiae, B. subtilis and human. Overall, these data sets encompass more than twenty conditions, each containing dozens (28-108) of simultaneously measured metabolites. We test for correlations with various physico-chemical properties and find that the number of charged atoms, non-polar surface area, lipophilicity and solubility consistently correlate with concentration. In most data sets, a change in one of these properties elicits a ∼100 fold increase in metabolite concentrations. We find that the non-polar surface area and number of charged atoms account for almost half of the variation in concentrations in the most reliable and comprehensive data set. Analyzing specific groups of metabolites, such as amino-acids or phosphorylated nucleotides, reveals even a higher dependence of concentration on hydrophobicity. We suggest that these findings can be explained by evolutionary constraints imposed on metabolite concentrations and discuss possible selective pressures that can account for them. These include the reduction of solute leakage through the lipid membrane, avoidance of deleterious aggregates and reduction of non-specific hydrophobic binding. By highlighting the global constraints imposed on metabolic pathways, future research could shed light onto aspects of biochemical evolution and the chemical constraints that bound metabolic engineering efforts. PMID:21998563

  11. Microbial production of isoquinoline alkaloids as plant secondary metabolites based on metabolic engineering research.

    PubMed

    Sato, Fumihiko; Kumagai, Hidehiko

    2013-01-01

    Plants produce a variety of secondary metabolites that possess strong physiological activities. Unfortunately, however, their production can suffer from a variety of serious problems, including low levels of productivity and heterogeneous quality, as well as difficulty in raw material supply. In contrast, microorganisms can be used to produce their primary and some of their secondary metabolites in a controlled environment, thus assuring high levels of efficiency and uniform quality. In an attempt to overcome the problems associated with secondary metabolite production in plants, we developed a microbial platform for the production of plant isoquinoline alkaloids involving the unification of the microbial and plant metabolic pathways into a single system. The potential applications of this system have also been discussed.

  12. Isolation and screening of proangiogenic and antiangiogenic metabolites producing rare actinobacteria from soil.

    PubMed

    Azarakhsh, Y; Mohammadipanah, F; Nassiri, S M; Siavashi, V; Hamedi, J

    2017-06-01

    Angiogenesis is a physiological process that has important impacts on the pathology and healing of various diseases, and its induction or inhibition by bioactive actinobacterial metabolites can help the treatment of some diseases. In this study, the effects of actinobacterial extract in the process of angiogenesis have been explored. In this research, proangiogenic and antiangiogenic metabolites producing actinobacteria were isolated from soil samples and their fermentation broth were extracted and after evaluation of their toxicity by MTT assay, antiangiogenic and proangiogenic activities were screened against human umbilical vein endothelial cells (HUVECs) by in vitro tube formation and migration assay. Isolated strains were identified through molecular techniques. The results showed that Nocardiopsis arvandica UTMC 103 and Nonomuraea sp. UTMC 2180 extracts had a high potential of anti-angiogenic activity on HUVECs. For the first time proangiogenic potency of a rare actinobacterium, Kribbella sp. UTMC 522, was reported, and N. arvandica UTMC 103 and Nonomuraea sp. UTMC 2180 extracts inhibits the proliferation, migration and angiogenesis activity of HUVECs with reasonable potency. Metabolites of the introduced rare actinobacteria are potent proangiogenic and angiogenic inhibitors. Identification of angiogenic-antiangiogenic mechanisms and purification of the extracts would be useful in therapeutic angiogenesis. © 2017 The Society for Applied Microbiology.

  13. Combined analytical approaches to define biodistribution and biological activity of semi-synthetic berberrubine, the active metabolite of natural berberine.

    PubMed

    Porru, Emanuele; Franco, Placido; Calabria, Donato; Spinozzi, Silvia; Roberti, Marinella; Caliceti, Cristiana; Roda, Aldo

    2018-06-01

    Berberine (BBR) is a natural alkaloid obtained from Berberis species plants, known for its protective effects against several diseases. Among the primary BBR metabolites, berberrubine (M1) showed the highest plasma concentration but few and conflicting data are available regarding its concentration in biological fluids related to its new potential activity on vascular cells. A combined analytical approach was applied to study biodistribution of M1 in comparison with BBR. The optimization of sample clean-up combined with a fully validated HPLC-ESI-MS/MS tailored for M1 allows sufficient detectability and accuracy to be reached in the different studied organs even when administered at low dose, comparable to that assumed by human. A predictive human vascular endothelial cell-based assay to measure intracellular xanthine oxidase has been developed and applied to study unexplored activities of M1 alongside other common activities. Results showed that oral M1 treatment exhibits higher plasma levels than BBR, reaching maximum concentration 400-fold higher than BBR (204 vs 0.5 ng/mL); moreover, M1 exhibits higher concentrations than BBR also in all the biological compartments analyzed. Noteworthy, the two compounds follow two different excretion routes: M1 through urine, while BBR through feces. In vitro studies demonstrated that M1 inhibited intracellular xanthine oxidase activity, one of the major sources of reactive oxygen species in vasculature, with an IC50 = 9.90 ± 0.01 μg/mL and reduced the expression of the inflammatory marker ICAM-1. These peculiar characteristics allow new perspectives to be opened up for the direct use of M1 instead of BBR in endothelial dysfunction treatment.

  14. Dietary supplemental Kluyveromyces marxianus alters the serum metabolite profile in broiler chickens.

    PubMed

    Wang, Weiwei; Li, Zhui; Gan, Liping; Fan, Hao; Guo, Yuming

    2018-06-18

    Metabolomics is used to evaluate the bioavailability of food components, as well as to validate the metabolic changes associated with food consumption. This study was conducted to investigate the effects of the dietary supplement Kluyveromyces marxianus on the serum metabolite profile in broiler chickens. A total of 240 1-d-old broilers were divided into 2 groups with 8 replicates. Birds were fed basal diets without or with K. marxianus supplementation (5 × 1010 CFU kg-1 of diet). Serum samples were collected on d 21 and were analyzed by high-performance liquid chromatography with quadrupole time-of flight/mass spectrometry. The results showed that supplemental K. marxianus altered the concentrations of a variety of metabolites in the serum. Thereinto, a total of 39 metabolites were identified at higher (P < 0.05) concentrations while 21 metabolites were identified at lower (P < 0.05) concentrations in the treatment group as compared with the control. These metabolites were primarily involved with the regulation of amino acids and carbohydrate metabolism. Further metabolic pathway analysis revealed that glutamine and glutamate metabolism was the most relevant and critical pathway identified from these two groups. The activated pathway may partially interpret the beneficial effects of K. marxianus. Overall, the present research could promote our understanding of the probiotic action of K. marxianus and provide new insight into the design and application of K. marxianus-containing functional foods.

  15. The gut microbiota metabolite indole alleviates liver inflammation in mice.

    PubMed

    Beaumont, Martin; Neyrinck, Audrey M; Olivares, Marta; Rodriguez, Julie; de Rocca Serra, Audrey; Roumain, Martin; Bindels, Laure B; Cani, Patrice D; Evenepoel, Pieter; Muccioli, Giulio G; Demoulin, Jean-Baptiste; Delzenne, Nathalie M

    2018-06-15

    The gut microbiota regulates key hepatic functions, notably through the production of bacterial metabolites that are transported via the portal circulation. We evaluated the effects of metabolites produced by the gut microbiota from aromatic amino acids (phenylacetate, benzoate, p-cresol, and indole) on liver inflammation induced by bacterial endotoxin. Precision-cut liver slices prepared from control mice, Kupffer cell (KC)-depleted mice, and obese mice ( ob/ ob) were treated with or without LPS and bacterial metabolites. We observed beneficial effects of indole that dose-dependently reduced the LPS-induced up-regulation of proinflammatory mediators at both mRNA and protein levels in precision-cut liver slices prepared from control or ob/ ob mice. KC depletion partly prevented the antiinflammatory effects of indole, notably through a reduction of nucleotide-binding domain and leucine-rich repeat containing (NLR) family pyrin domain-containing 3 (NLRP3) pathway activation. In vivo, the oral administration of indole before an LPS injection reduced the expression of key proteins of the NF-κB pathway and downstream proinflammatory gene up-regulation. Indole also prevented LPS-induced alterations of cholesterol metabolism through a transcriptional regulation associated with increased 4β-hydroxycholesterol hepatic levels. In summary, indole appears as a bacterial metabolite produced from tryptophan that is able to counteract the detrimental effects of LPS in the liver. Indole could be a new target to develop innovative strategies to decrease hepatic inflammation.-Beaumont, M., Neyrinck, A. M., Olivares, M., Rodriguez, J., de Rocca Serra, A., Roumain, M., Bindels, L. B., Cani, P. D., Evenepoel, P., Muccioli, G. G., Demoulin, J.-B., Delzenne, N. M. The gut microbiota metabolite indole alleviates liver inflammation in mice.

  16. Hot flashes are not predictive for serum concentrations of tamoxifen and its metabolites

    PubMed Central

    2013-01-01

    Background Tamoxifen has dramatically reduced the recurrence and mortality rate of estrogen receptor positive breast cancer. However, the efficacy of tamoxifen varies between individuals and 40% of patients will have a recurrence despite adjuvant tamoxifen treatment. Factors that predict tamoxifen efficacy would be helpful for optimizing treatment. Serum concentrations of the active metabolite, endoxifen, may be positively related to treatment outcome. In addition, hot flashes are suggested to be positively associated with tamoxifen treatment outcome. Methods We investigated in a series of 109 patients whether the frequency and severity of hot flashes were related to concentrations of tamoxifen and its metabolites. A serum sample of all patients was analyzed for the concentration of tamoxifen, N-desmethyltamoxifen, endoxifen and 4-hydroxytamoxifen, as well as for estradiol concentrations and several single nucleotide polymorphisms in CYP2D6. Additionally, these patients completed a questionnaire concerning biometric data and treatment side effects. Results We found no evidence supporting an association between concentrations of tamoxifen or metabolites and either the frequency or severity of hot flashes in the covariate unadjusted analyses. However, including interactions with menopausal status and pre-treatment hot flash (PTHF) history indicated that post-menopausal women with PTHF experienced an increasing frequency of hot flashes with increasing serum concentrations of tamoxifen and its metabolites. This finding was not altered when adjusting for potential confounding factors (duration of tamoxifen treatment, CYP2D6 phenotype, estradiol serum concentration, age and body mass index). In addition we observed a positive association between body mass index and both hot flash frequency (p = 0.04) and severity (p < 0.0001). We also observed that patients with lower estradiol levels reported more severe hot flashes (p = 0.02). Conclusions No univariate

  17. Occurrence of selected pharmaceuticals at drinking water purification plants in Japan and implications for human health.

    PubMed

    Simazaki, Dai; Kubota, Reiji; Suzuki, Toshinari; Akiba, Michihiro; Nishimura, Tetsuji; Kunikane, Shoichi

    2015-06-01

    The present study was performed to determine the occurrence of 64 pharmaceuticals and metabolites in source water and finished water at 6 drinking water purification plants and 2 industrial water purification plants across Japan. The analytical methods employed were sample concentration using solid-phase extraction cartridges and instrumental analysis by liquid chromatography with tandem mass spectrometry (LC-MS/MS), liquid chromatography with mass spectrometry (LC/MS), or trimethylsilyl derivatization followed by gas chromatography with mass spectrometry (GC/MS). Thirty-seven of the 64 target substances were detected in the source water samples. The maximum concentrations in the source water were mostly below 50 ng/L except for 13 substances. In particular, residual concentrations of iopamidol (contrast agent) exceeded 1000 ng/L at most facilities. Most of the residual pharmaceuticals and metabolites in the source water samples were removed in the course of conventional and/or advanced drinking water treatments, except for 7 pharmaceuticals and 1 metabolite, i.e., amantadine, carbamazepine, diclofenac, epinastine, fenofibrate, ibuprofen, iopamidol, and oseltamivir acid. The removal ratios of the advanced water treatment processes including ozonation and granular activated carbon filtration were typically much higher than those of the conventional treatment processes. The margins of exposure estimated by the ratio of daily minimum therapeutic dose to daily intake via drinking water were substantial, and therefore the pharmacological and physiological impacts of ingesting those residual substances via drinking water would be negligible. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Effect of CYP2B6 genotype on the pharmacokinetics of sibutramine and active metabolites in healthy subjects.

    PubMed

    Chung, Jae Yong; Jang, Seong Bok; Lee, Yoon Jung; Park, Min Soo; Park, Kyungsoo

    2011-01-01

    Sibutramine is a pharmacologic intervention for the treatment of obesity. The effect of CYP2B6 genotypes on the pharmacokinetics of sibutramine and its active metabolites (desmethylsibutramine [M1] and didesmethylsibutramine [M2]) was evaluated in 57 healthy subjects. Each subject received a single oral dose of 10 or 15 mg sibutramine, and blood samples were collected up to 72 hours after dosing. The relationship between the genotypes and the pharmacokinetics of sibutramine, M1, and M2 was examined. A statistically significant difference in the elimination half-life (t(1/2)) of sibutramine M1 was found among the 3 genotype groups (P = .0006), between the *1/*1 and *1/*6 groups (P = .0001), and between the *1/*4 and *1/*6 groups (P = .012). The mean value of M1 t(1/2) in *1/*6 (33.3 ± 10.5 hours) was about 58% and 61% greater than that of the *1/*1 group (21.0 ± 7.4 hours) and the *1/*4 group (20.7 ± 9.8 hours), respectively. No significant differences in area under the concentration-time curve or maximum plasma drug concentration were observed between the groups. The CYP2B6*6 allele may be associated with a lower metabolic clearance of the M1 metabolite of sibutramine in human subjects.

  19. Secondary metabolites of Eichhornia crassipes (Waterhyacinth): a review (1949 to 2011).

    PubMed

    Lalitha, Pottail; Sripathi, Shubashini K; Jayanthi, Ponnusamy

    2012-09-01

    Eichhornia crassipes (Mart.) Solms (Waterhyacinth), an aquatic perennial herb present throughout the world, has a myriad of metabolites. Phenalenone compounds and sterols have been isolated from this plant. Extracts, as well as pure compounds isolated from this plant, have been demonstrated to possess pharmacological activities. An account of the phytochemistry, pharmacological activities and several applications ofwaterhyacinth are included in this review.

  20. FECAL PROGESTERONE METABOLITES IN POSTPARTUM SIBERIAN FLYING SQUIRRELS.

    PubMed

    Shimamoto, Tatsuki; Suzuki, Kei K; Hamada, Mizuho; Furukawa, Ryuji; Matsui, Motozumi; Yanagawa, Hisashi

    2018-03-01

    The Siberian flying squirrel ( Pteromys volans) produces up to two litters a year. To deliver second litters in breeding season, P. volans may have a postpartum estrus similarly to that of a variety of small mammals. If this were the case, females would have periods of elevated progesterone levels because of the formation of corpora lutea (CL) after postpartum ovulation. To test this hypothesis, fecal progesterone metabolite dynamics was investigated during lactation in this species using an enzyme immunoassay. In five of the six lactating females, periods of high fecal progesterone metabolite concentration were observed, and, furthermore, progesterone secretion patterns were periodic. Therefore, the source of progesterone during lactation could be arising CL from postpartum ovulation, indicating that ovarian activity was reinitiated after parturition and the CL that formed began secreting progesterone. This study thus showed that P. volans likely has the physiologic potential to mate during lactation.

  1. A Unique Automation Platform for Measuring Low Level Radioactivity in Metabolite Identification Studies

    PubMed Central

    Krauser, Joel; Walles, Markus; Wolf, Thierry; Graf, Daniel; Swart, Piet

    2012-01-01

    Generation and interpretation of biotransformation data on drugs, i.e. identification of physiologically relevant metabolites, defining metabolic pathways and elucidation of metabolite structures, have become increasingly important to the drug development process. Profiling using 14C or 3H radiolabel is defined as the chromatographic separation and quantification of drug-related material in a given biological sample derived from an in vitro, preclinical in vivo or clinical study. Metabolite profiling is a very time intensive activity, particularly for preclinical in vivo or clinical studies which have defined limitations on radiation burden and exposure levels. A clear gap exists for certain studies which do not require specialized high volume automation technologies, yet these studies would still clearly benefit from automation. Use of radiolabeled compounds in preclinical and clinical ADME studies, specifically for metabolite profiling and identification are a very good example. The current lack of automation for measuring low level radioactivity in metabolite profiling requires substantial capacity, personal attention and resources from laboratory scientists. To help address these challenges and improve efficiency, we have innovated, developed and implemented a novel and flexible automation platform that integrates a robotic plate handling platform, HPLC or UPLC system, mass spectrometer and an automated fraction collector. PMID:22723932

  2. Structural Characterization of a Therapeutic Anti-Methamphetamine Antibody Fragment: Oligomerization and Binding of Active Metabolites

    PubMed Central

    Gokulan, Kuppan; Varughese, Kottayil I.

    2013-01-01

    Vaccines and monoclonal antibodies (mAb) for treatment of (+)-methamphetamine (METH) abuse are in late stage preclinical and early clinical trial phases, respectively. These immunotherapies work as pharmacokinetic antagonists, sequestering METH and its metabolites away from sites of action in the brain and reduce the rewarding and toxic effects of the drug. A key aspect of these immunotherapy strategies is the understanding of the subtle molecular interactions important for generating antibodies with high affinity and specificity for METH. We previously determined crystal structures of a high affinity anti-METH therapeutic single chain antibody fragment (scFv6H4, KD = 10 nM) in complex with METH and the (+) stereoisomer of 3,4-methylenedioxymethamphetamine (MDMA, or “ecstasy”). Here we report the crystal structure of scFv6H4 in homo-trimeric unbound (apo) form (2.60Å), as well as monomeric forms in complex with two active metabolites; (+)-amphetamine (AMP, 2.38Å) and (+)-4-hydroxy methamphetamine (p-OH-METH, 2.33Å). The apo structure forms a trimer in the crystal lattice and it results in the formation of an intermolecular composite beta-sheet with a three-fold symmetry. We were also able to structurally characterize the coordination of the His-tags with Ni2+. Two of the histidine residues of each C-terminal His-tag interact with Ni2+ in an octahedral geometry. In the apo state the CDR loops of scFv6H4 form an open conformation of the binding pocket. Upon ligand binding, the CDR loops adopt a closed formation, encasing the drug almost completely. The structural information reported here elucidates key molecular interactions important in anti-methamphetamine abuse immunotherapy. PMID:24349338

  3. Evaluation of loxoprofen and its alcohol metabolites for potency and selectivity of inhibition of cyclooxygenase-2.

    PubMed

    Riendeau, Denis; Salem, Myriam; Styhler, Angela; Ouellet, Marc; Mancini, Joseph A; Li, Chun Sing

    2004-03-08

    Loxoprofen, its trans-alcohol and cis-alcohol metabolites were evaluated for selectivity of inhibition of COX-2 over COX-1. The (2S,1'R,2'S)-trans-alcohol derivative was found to be the most active metabolite and to be a potent and nonselective inhibitor of COX-2 and COX-1 in both enzyme and human whole blood assays.

  4. Pharmacokinetics of isotretinoin and its major blood metabolite following a single oral dose to man.

    PubMed

    Colburn, W A; Vane, F M; Shorter, H J

    1983-01-01

    A pharmacokinetic profile of isotretinoin and its major dermatologically active blood metabolite, 4-oxo-isotretinoin, was developed following a single 80 mg oral suspension dose of isotretinoin to 15 normal male subjects. Blood samples were assayed for isotretinoin and 4-oxo-isotretinoin using a newly developed reverse-phase HPLC method. Following rapid absorption from the suspension formulation, isotretinoin is distributed and eliminated with harmonic mean half-lives of 1.3 and 17.4 h, respectively. Maximum concentrations of isotretinoin in blood were observed at 1 to 4 h after dosing. Maximum concentrations of the major blood metabolite of isotretinoin, 4-oxo-isotretinoin, are approximately one-half those of isotretinoin and occur at 6 to 16 h after isotretinoin dosing. The ratio of areas under the curve for metabolite and parent drug following the single dose suggests that average steady-state ratios of metabolite to parent drug during a dosing interval will be approximately 2.5. Both isotretinoin and its metabolite can be adequately described using a single linear pharmacokinetic model.

  5. Drug repositioning for enzyme modulator based on human metabolite-likeness.

    PubMed

    Lee, Yoon Hyeok; Choi, Hojae; Park, Seongyong; Lee, Boah; Yi, Gwan-Su

    2017-05-31

    Recently, the metabolite-likeness of the drug space has emerged and has opened a new possibility for exploring human metabolite-like candidates in drug discovery. However, the applicability of metabolite-likeness in drug discovery has been largely unexplored. Moreover, there are no reports on its applications for the repositioning of drugs to possible enzyme modulators, although enzyme-drug relations could be directly inferred from the similarity relationships between enzyme's metabolites and drugs. We constructed a drug-metabolite structural similarity matrix, which contains 1,861 FDA-approved drugs and 1,110 human intermediary metabolites scored with the Tanimoto similarity. To verify the metabolite-likeness measure for drug repositioning, we analyzed 17 known antimetabolite drugs that resemble the innate metabolites of their eleven target enzymes as the gold standard positives. Highly scored drugs were selected as possible modulators of enzymes for their corresponding metabolites. Then, we assessed the performance of metabolite-likeness with a receiver operating characteristic analysis and compared it with other drug-target prediction methods. We set the similarity threshold for drug repositioning candidates of new enzyme modulators based on maximization of the Youden's index. We also carried out literature surveys for supporting the drug repositioning results based on the metabolite-likeness. In this paper, we applied metabolite-likeness to repurpose FDA-approved drugs to disease-associated enzyme modulators that resemble human innate metabolites. All antimetabolite drugs were mapped with their known 11 target enzymes with statistically significant similarity values to the corresponding metabolites. The comparison with other drug-target prediction methods showed the higher performance of metabolite-likeness for predicting enzyme modulators. After that, the drugs scored higher than similarity score of 0.654 were selected as possible modulators of enzymes for

  6. Extraction and isolation of the salidroside-type metabolite from zinc (Zn) and cadmium (Cd) hyperaccumulator Sedum alfredii Hance*

    PubMed Central

    Xing, Yan; Peng, Hong-yun; Li, Xia; Zhang, Meng-xi; Gao, Ling-ling; Yang, Xiao-e

    2012-01-01

    The active metabolite in the post-harvested biomass of zinc (Zn) and cadmium (Cd) hyperaccumulator Sedum alfredii Hance from phytoextraction is of great interest in China. The current study demonstrates that a salidroside-type metabolite can be yielded from the Zn/Cd hyperaccumulator S. alfredii biomass by means of sonication/ethanol extraction and macroporous resin column (AB-8 type) isolation. The concentrations of Zn and Cd in the salidroside-type metabolite were below the limitation of the national standards. PMID:23024051

  7. Lipoxygenases and their metabolites in formation of plant stress tolerance.

    PubMed

    Babenko, L M; Shcherbatiuk, M M; Skaterna, T D; Kosakivska, I V

    2017-01-01

    The review focuses on the analysis of new information concerning molecular enzymology of lipoxygenases – proteins involved in lipid peroxidation and found in animals and plants. Modern concept of structural features, catalytic characteristics and functions of lipoxygenase family enzymes as well as products of their catalytic activity in plants have been discussed and summarized. Issues of enzyme localization in plant cells and tissues, evolution and distribution of lipoxygenases, involvement in production of signaling substances involved in formation of adaptation response to abiotic and biotic stress factors and in regulation of lipoxygenase signal system activity are highlighted. Participants of the elements signaling of LOX-pathway reception and transduction into genome are considered. Special attention is given to jasmonates, metabolites of the allene oxide synthase branch of the lipoxygenase cascade, because these metabolites have high biological activity, are ubiquitously present in all plant organisms, and are involved in regulation of vitally important processes. Data concerning lipoxygenase phylogeny, possible occurrence of a common predecessor for modern isoforms of the enzyme in pro- and eukaryote have been examined. Some results of our studies that open up possibilities of using the lipoxygenase catalytic activity characteristics as biological markers in plant stress tolerance researches are given.

  8. The WEIZMASS spectral library for high-confidence metabolite identification

    NASA Astrophysics Data System (ADS)

    Shahaf, Nir; Rogachev, Ilana; Heinig, Uwe; Meir, Sagit; Malitsky, Sergey; Battat, Maor; Wyner, Hilary; Zheng, Shuning; Wehrens, Ron; Aharoni, Asaph

    2016-08-01

    Annotation of metabolites is an essential, yet problematic, aspect of mass spectrometry (MS)-based metabolomics assays. The current repertoire of definitive annotations of metabolite spectra in public MS databases is limited and suffers from lack of chemical and taxonomic diversity. Furthermore, the heterogeneity of the data prevents the development of universally applicable metabolite annotation tools. Here we present a combined experimental and computational platform to advance this key issue in metabolomics. WEIZMASS is a unique reference metabolite spectral library developed from high-resolution MS data acquired from a structurally diverse set of 3,540 plant metabolites. We also present MatchWeiz, a multi-module strategy using a probabilistic approach to match library and experimental data. This strategy allows efficient and high-confidence identification of dozens of metabolites in model and exotic plants, including metabolites not previously reported in plants or found in few plant species to date.

  9. Testosterone metabolism revisited: discovery of new metabolites.

    PubMed

    Pozo, Oscar J; Marcos, Josep; Ventura, Rosa; Fabregat, Andreu; Segura, Jordi

    2010-10-01

    The metabolism of testosterone is revisited. Four previously unreported metabolites were detected in urine after hydrolysis with KOH using a liquid chromatography-tandem mass spectrometry method and precursor ion scan mode. The metabolites were characterized by a product ion scan obtained with accurate mass measurements. Androsta-4,6-dien-3,17-dione, androsta-1,4-dien-3,17-dione, 17-hydroxy-androsta-4,6-dien-3-one and 15-androsten-3,17-dione were proposed as feasible structures for these metabolites on the basis of the mass spectrometry data. The proposed structures were confirmed by analysis of synthetic reference compounds. Only 15-androsten-3,17-dione could not be confirmed, owing to the lack of a commercially available standard. That all four compounds are testosterone metabolites was confirmed by the qualitative analysis of several urine samples collected before and after administration of testosterone undecanoate. The metabolite androsta-1,4-dien-3,17-dione has a structure analogous to that of the exogenous anabolic steroid boldenone. Specific transitions for boldenone and its metabolite 17β-hydroxy-5β-androst-1-en-3-one were also monitored. Both compounds were also detected after KOH treatment, suggesting that this metabolic pathway is involved in the endogenous detection of boldenone previously reported by several authors.

  10. [Antagonism against Beauveria bassiana by lipopeptide metabolites produced by entophyte Bacillus amyloliquefaciens strain SWB16].

    PubMed

    Wang, Jingjie; Zhao, Dongyang; Liu, Yonggui; Ao, Xiang; Fan, Rui; Duan, Zhengqiao; Liu, Yanping; Chen, Qianqian; Jin, Zhixiong; Wan, Yongji

    2014-07-04

    We screened bacterial strains that have strong antagonism against Beauveria bassiana, an important pathogen of silkworm industry, and detected the antagonistic activity of lipopeptide metabolites. We identified bacterium SWB16 by morphological observation, physiological and biochemical experiments, 16SrRNA, and gyrA gene sequence analysis, tested antagonistic activity of strain SWB16 against Beauveria bassiana by measuring the inhibition zone diameter using filter paper diffusion method (Kirby-Bauer method), obtained lipopeptide metabolites of the strain using methanol extraction and observed the antagonism of strain SWB16 lipopeptide extracts against the conidia and hyphae of Beauveria bassiana, detected main ingredients and genes of lipopeptide metabolites by high-performance liquid chromatography-mass spectrometry and PCR amplification. SWB16 isolated from tissue of plant Dioscorea zingiberensis C. H. Wright belongs to Bacillus amyloliquefaciens and showed high antagonistic activity to Beauveria bassiana, and the lipopeptide extracts of isolate SWB16 exhibited significant inhibition to conidial germination and mycelial growth of Beauveria bassiana. The result of mass spectrometric detection indicated main component of the lipopeptide metabolites were fengcin and iturin, and genes fenB, ituA involved in the synthesis of them were amplified in the genome. Bacillus amyloliquefaciens strain SWB16 could produce lipopeptide antibiotics with strong antagonism to the entomopathogenic fungus Beauveria bassiana, and the results suggested that strain SWB16 has potential application value for controlling white muscardine of economic insects including silkworm.

  11. Identification, quantification, spatiotemporal distribution and genetic variation of major latex secondary metabolites in the common dandelion (Taraxacum officinale agg.).

    PubMed

    Huber, Meret; Triebwasser-Freese, Daniella; Reichelt, Michael; Heiling, Sven; Paetz, Christian; Chandran, Jima N; Bartram, Stefan; Schneider, Bernd; Gershenzon, Jonathan; Erb, Matthias

    2015-07-01

    The secondary metabolites in the roots, leaves and flowers of the common dandelion (Taraxacum officinale agg.) have been studied in detail. However, little is known about the specific constituents of the plant's highly specialized laticifer cells. Using a combination of liquid and gas chromatography, mass spectrometry and nuclear magnetic resonance spectrometry, we identified and quantified the major secondary metabolites in the latex of different organs across different growth stages in three genotypes, and tested the activity of the metabolites against the generalist root herbivore Diabrotica balteata. We found that common dandelion latex is dominated by three classes of secondary metabolites: phenolic inositol esters (PIEs), triterpene acetates (TritAc) and the sesquiterpene lactone taraxinic acid β-D-glucopyranosyl ester (TA-G). Purification and absolute quantification revealed concentrations in the upper mgg(-1) range for all compound classes with up to 6% PIEs, 5% TritAc and 7% TA-G per gram latex fresh weight. Contrary to typical secondary metabolite patterns, concentrations of all three classes increased with plant age. The highest concentrations were measured in the main root. PIE profiles differed both quantitatively and qualitatively between plant genotypes, whereas TritAc and TA-G differed only quantitatively. Metabolite concentrations were positively correlated within and between the different compound classes, indicating tight biosynthetic co-regulation. Latex metabolite extracts strongly repelled D. balteata larvae, suggesting that the latex constituents are biologically active. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Enzymologic and pharmacologic profile of loxoprofen sodium and its metabolites.

    PubMed

    Noguchi, Masahiro; Kimoto, Aishi; Gierse, James Kevin; Walker, Mark Crossfield; Zweifel, Ben Scott; Nozaki, Kazutoshi; Sasamata, Masao

    2005-11-01

    We investigated the mechanism of inhibition of loxoprofen sodium, a non-steroidal anti-inflammatory drug (NSAID), and its active metabolite (loxoprofen-SRS) on cyclooxygenase (COX). In in vitro assays, loxoprofen sodium appeared inactive against recombinant human COX-1 and COX-2, whereas loxoprofen-SRS inhibited both. In the investigation of kinetic behavior, loxoprofen-SRS showed time-dependent inhibition for both isozymes. Human whole blood assay also showed that loxoprofen-SRS possesses the profile of a non-selective inhibitor for COX. In a rat air pouch model, oral administration of loxoprofen sodium lowered prostaglandin (PG) E2 in both fluid exudates of the inflammatory pouch and stomach tissue with ED50 values of 2.0 and 2.1 mg/kg, respectively. Additionally, platelet thromboxane B2 production was also inhibited by loxoprofen sodium (ED50 of 0.34 mg/kg). In a rat carrageenan-induced paw edema model, loxoprofen sodium dose-dependently reduced the paw edema, accompanied by a decrease in PGE2 content in inflamed paw exudates. These findings suggest that the COX inhibitory activity of loxoprofen sodium is attributable to its active metabolite, loxoprofen-SRS, and that loxoprofen-SRS shows non-selective inhibition for COX.

  13. Comparison of volatile and non-volatile metabolites in rice wine fermented by Koji inoculated with Saccharomycopsis fibuligera and Aspergillus oryzae.

    PubMed

    Son, Eun Yeong; Lee, Sang Mi; Kim, Minjoo; Seo, Jeong-Ah; Kim, Young-Suk

    2018-07-01

    This study investigated volatile and nonvolatile metabolite profiles of makgeolli (a traditional rice wine in Korea) fermented by koji inoculated with Saccharomycopsis fibuligera and/or Aspergillus oryzae. The enzyme activities in koji were also examined to determine their effects on the formation of metabolites. The contents of all 18 amino acids detected were the highest in makgeolli fermented by S. fibuligera CN2601-09, and increased after combining with A. oryzae CN1102-08, unlike the contents of most fatty acids. On the other hand, major volatile metabolites were fusel alcohols, acetate esters, and ethyl esters. The contents of most fusel alcohols and acetate esters were the highest in makgeolli fermented by S. fibuligera CN2601-09, for which the protease activity was the highest, leading to the largest amounts of amino acods. The makgeolli samples fermented only by koji inoculated with S. fibuligera could be discriminated on PCA plots from the makgeolli samples fermented in combination with A. oryzae. In the case of nonvolatile metabolites, all amino acids and some metabolites such as xylose, 2-methylbenzoic acid, and oxalic acid contributed mainly to the characteristics of makgeolli fermented by koji inoculated with S. fibuligera and A. oryzae. These results showed that the formations of volatile and nonvolatile metabolites in makgeolli can be significantly affected by microbial strains with different enzyme activities in koji. To our knowledge, this study is the first report on the effects of S. fibuligera strains on the formation of volatile and non-volatile metabolites in rice wine, facilitating their use in brewing rice wine. Copyright © 2018. Published by Elsevier Ltd.

  14. Comprehensive analyses of genomes, transcriptomes and metabolites of neem tree

    PubMed Central

    Rangiah, Kannan; Mahesh, HB; Rajamani, Anantharamanan; Shirke, Meghana D.; Russiachand, Heikham; Loganathan, Ramya Malarini; Shankara Lingu, Chandana; Siddappa, Shilpa; Ramamurthy, Aishwarya; Sathyanarayana, BN

    2015-01-01

    Neem (Azadirachta indica A. Juss) is one of the most versatile tropical evergreen tree species known in India since the Vedic period (1500 BC–600 BC). Neem tree is a rich source of limonoids, having a wide spectrum of activity against insect pests and microbial pathogens. Complex tetranortriterpenoids such as azadirachtin, salanin and nimbin are the major active principles isolated from neem seed. Absolutely nothing is known about the biochemical pathways of these metabolites in neem tree. To identify genes and pathways in neem, we sequenced neem genomes and transcriptomes using next generation sequencing technologies. Assembly of Illumina and 454 sequencing reads resulted in 267 Mb, which accounts for 70% of estimated size of neem genome. We predicted 44,495 genes in the neem genome, of which 32,278 genes were expressed in neem tissues. Neem genome consists about 32.5% (87 Mb) of repetitive DNA elements. Neem tree is phylogenetically related to citrus, Citrus sinensis. Comparative analysis anchored 62% (161 Mb) of assembled neem genomic contigs onto citrus chromomes. Ultrahigh performance liquid chromatography-mass spectrometry-selected reaction monitoring (UHPLC-MS/SRM) method was used to quantify azadirachtin, nimbin, and salanin from neem tissues. Weighted Correlation Network Analysis (WCGNA) of expressed genes and metabolites resulted in identification of possible candidate genes involved in azadirachtin biosynthesis pathway. This study provides genomic, transcriptomic and quantity of top three neem metabolites resource, which will accelerate basic research in neem to understand biochemical pathways. PMID:26290780

  15. Non-targeted metabolite profiling of citrus juices as a tool for variety discrimination and metabolite flow analysis.

    PubMed

    Arbona, Vicent; Iglesias, Domingo J; Gómez-Cadenas, Aurelio

    2015-02-05

    Genetic diversity of citrus includes intrageneric hybrids, cultivars arising from cross-pollination and/or somatic mutations with particular biochemical compounds such as sugar, acids and secondary metabolite composition. Secondary metabolite profiles of juices from 12 commercial varieties grouped into blonde and navel types, mandarins, lemons and grapefruits were analyzed by LC/ESI-QTOF-MS. HCA on metabolite profiling data revealed the existence of natural groups demarcating fruit types and varieties associated to specific composition patterns. The unbiased classification provided by HCA was used for PLS-DA to find the potential variables (mass chromatographic features) responsible for the classification. Abscisic acid and derivatives, several flavonoids and limonoids were identified by analysis of mass spectra. To facilitate interpretation, metabolites were represented as flow charts depicting biosynthetic pathways. Mandarins 'Fortune' and 'Hernandina' along with oranges showed higher ABA contents and ABA degradation products were present as glycosylated forms in oranges and certain mandarins. All orange and grapefruit varieties showed high limonin contents and its glycosylated form, that was only absent in lemons. The rest of identified limonoids were highly abundant in oranges. Particularly, Sucrenya cultivar showed a specific accumulation of obacunone and limonoate A-ring lactone. Polymethoxylated flavanones (tangeritin and isomers) were absolutely absent from lemons and grapefruits whereas kaempferol deoxyhexose hexose isomer #2, naringin and neohesperidin were only present in these cultivars. Analysis of relative metabolite build-up in closely-related genotypes allowed the efficient demarcation of cultivars and suggested the existence of genotype-specific regulatory mechanisms underlying the differential metabolite accumulation.

  16. Secondary metabolites: applications on cultural heritage.

    PubMed

    Sasso, S; Scrano, L; Bonomo, M G; Salzano, G; Bufo, S A

    2013-01-01

    Biological sciences and related bio-technology play a very important role in research projects concerning protection and preservation of cultural heritage for future generations. In this work secondary metabolites of Burkholderia gladioli pv. agaricicola (Bga) ICMP 11096 strain and crude extract of glycoalkaloids from Solanaceae plants, were tested against a panel of microorganisms isolated from calcarenite stones of two historical bridges located in Potenza and in Campomaggiore (Southern Italy). The isolated bacteria belong to Bacillus cereus and Arthrobacter agilis species, while fungi belong to Aspergillus, Penicillium, Coprinellus, Fusarium, Rhizoctonio and Stemphylium genera. Bga broth (unfiltered) and glycoalkaloids extracts were able to inhibit the growth of all bacterial isolates. Bga culture was active against fungal colonies, while Solanaceae extract exerted bio-activity against Fusarium and Rhizoctonia genera.

  17. Effects of Olive Metabolites on DNA Cleavage Mediated by Human Type II Topoisomerases

    PubMed Central

    2016-01-01

    Several naturally occurring dietary polyphenols with chemopreventive or anticancer properties are topoisomerase II poisons. To identify additional phytochemicals that enhance topoisomerase II-mediated DNA cleavage, a library of 341 Mediterranean plant extracts was screened for activity against human topoisomerase IIα. An extract from Phillyrea latifolia L., a member of the olive tree family, displayed high activity against the human enzyme. On the basis of previous metabolomics studies, we identified several polyphenols (hydroxytyrosol, oleuropein, verbascoside, tyrosol, and caffeic acid) as potential candidates for topoisomerase II poisons. Of these, hydroxytyrosol, oleuropein, and verbascoside enhanced topoisomerase II-mediated DNA cleavage. The potency of these olive metabolites increased 10–100-fold in the presence of an oxidant. Hydroxytyrosol, oleuropein, and verbascoside displayed hallmark characteristics of covalent topoisomerase II poisons. (1) The activity of the metabolites was abrogated by a reducing agent. (2) Compounds inhibited topoisomerase II activity when they were incubated with the enzyme prior to the addition of DNA. (3) Compounds were unable to poison a topoisomerase IIα construct that lacked the N-terminal domain. Because hydroxytyrosol, oleuropein, and verbascoside are broadly distributed across the olive family, extracts from the leaves, bark, and fruit of 11 olive tree species were tested for activity against human topoisomerase IIα. Several of the extracts enhanced enzyme-mediated DNA cleavage. Finally, a commercial olive leaf supplement and extra virgin olive oils pressed from a variety of Olea europea subspecies enhanced DNA cleavage mediated by topoisomerase IIα. Thus, olive metabolites appear to act as topoisomerase II poisons in complex formulations intended for human dietary consumption. PMID:26132160

  18. Fluoxetine and its active metabolite norfluoxetine disrupt estrogen synthesis in a co-culture model of the feto-placental unit.

    PubMed

    Hudon Thibeault, Andrée-Anne; Laurent, Laetitia; Vo Duy, Sung; Sauvé, Sébastien; Caron, Patrick; Guillemette, Chantal; Sanderson, J Thomas; Vaillancourt, Cathy

    2017-02-15

    The effects of fluoxetine, one of the most prescribed selective serotonin-reuptake inhibitors (SSRIs) during pregnancy, and its active metabolite norfluoxetine were studied on placental aromatase (CYP19) and feto-placental steroidogenesis. Fluoxetine did not alter estrogen secretion in co-culture of fetal-like adrenocortical (H295R) and trophoblast-like (BeWo) cells used as a model of the feto-placental unit, although it induced CYP19 activity, apparently mediated by the serotonin (5-HT) 2A receptor/PKC signaling pathway. Norfluoxetine decreased estrogen secretion in the feto-placental co-culture and competitively inhibited catalytic CYP19 activity in BeWo cells. Decreased serotonin transporter (SERT) activity in the co-culture was comparable to 17β-estradiol treatment of BeWo cells. This work shows that the complex interaction of fluoxetine and norfluoxetine with placental estrogen production, involves 5-HT-dependent and -independent mechanisms. Considering the crucial role of estrogens during pregnancy, our results raise concern about the impact of SSRI treatment on placental function and fetal health. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  19. A search for antiplasmodial metabolites among fungal endophytes of terrestrial and marine plants of southern India.

    PubMed

    Kaushik, Naveen Kumar; Murali, Thokur Sreepathy; Sahal, Dinkar; Suryanarayanan, T S

    2014-10-01

    Eighty four different fungal endophytes isolated from sea grasses (5), marine algae (36) and leaves or barks of forest trees (43) were grown in vitro and the secondary metabolites secreted by them were harvested by immobilizing them on XAD beads. These metabolites were eluted with methanol and screened using SYBR Green I assay for their antiplasmodial activity against blood stage Plasmodium falciparum in human red blood cell culture. Our results revealed that fungal endophytes belonging to diverse genera elaborate antiplasmodial metabolites. A Fusarium sp. (580, IC50: 1.94 μg ml(-1)) endophytic in a marine alga and a Nigrospora sp. (151, IC50: 2.88 μg ml(-1)) endophytic in a tree species were subjected to antiplasmodial activity-guided reversed phase high performance liquid chromatography separation. Purification led to potentiation as reflected in IC50 values of 0.12 μg ml(-1) and 0.15 μg ml(-1) for two of the fractions obtained from 580. Our study adds further credence to the notion that fungal endophytes are a potential storehouse for a variety of novel secondary metabolites vested with different bioactivities including some that can stall the growth of the malaria parasite.

  20. Analytical characterization and structure elucidation of metabolites from Aspergillus ochraceus MP2 fungi.

    PubMed

    Meenupriya, J; Thangaraj, M

    2011-10-01

    To isolate and characterize the bioactive secondary metabolites from Aspergillus ochraceus (A. ochraceus) MP2 fungi. The anti bacterial activity of marine sponge derived fungi A. ochraceus MP2 was thoroughly investigated against antagonistic human pathogens. The optimum inhibitory concentration of the fungi in the elite solvent was also determined. The promising extracts that showed good antimicrobial activity were subjected to further analytical separation to get individual distinct metabolites and the eluants were further identified by GC MS instrumental analysis. The molecular characterization of the elite fungal strains were done by isolating their genomic DNA and amplify the internal transcribed spacer (ITS) region of 5.8s rRNA using specific ITS primer. The novelty of the strain was proved by homology search tools and elite sequences was submitted to GENBANK. Three bioactive compounds were characterized to reveal their identity, chemical formula and structure. The first elutant was identified asα- Campholene aldehyde with chemical formula C10 H16 O and molecular weight 152 Da. The second elutant was identified as Lucenin-2 and chemical formula C27 H30 O16 and molecular weight 610 Da. The third elutant was identified as 6-Ethyloct- 3-yl- 2- ethylhexyl ester with Chemical formula C26 H42 O4 with molecular weight 418 Da. The isolated compounds showed significant antimicrobial activity against potential human pathogens. Microbial secondary metabolites represent a large source of compounds endowed with ingenious structures and potent biological activities.